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Slightly gratuitous logeventf() crusade and purge of fixed-length buffers.
[u/mdw/putty] / ssh.c
CommitLineData
374330e2 1#include <stdio.h>
2#include <stdlib.h>
fb09bf1c 3#include <stdarg.h>
4#include <assert.h>
374330e2 5
6#include "putty.h"
dacbd0e8 7#include "tree234.h"
fb09bf1c 8#include "ssh.h"
374330e2 9
10#ifndef FALSE
11#define FALSE 0
12#endif
13#ifndef TRUE
14#define TRUE 1
15#endif
16
32874aea 17#define SSH1_MSG_DISCONNECT 1 /* 0x1 */
18#define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
19#define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
20#define SSH1_CMSG_USER 4 /* 0x4 */
21#define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
22#define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
23#define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
24#define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
25#define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
26#define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
27#define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
28#define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
29#define SSH1_SMSG_SUCCESS 14 /* 0xe */
30#define SSH1_SMSG_FAILURE 15 /* 0xf */
31#define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
32#define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
33#define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
34#define SSH1_CMSG_EOF 19 /* 0x13 */
35#define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
36#define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
37#define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
38#define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
39#define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
40#define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
41#define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
42#define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
43#define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
44#define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
45#define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
46#define SSH1_MSG_IGNORE 32 /* 0x20 */
47#define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
48#define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
49#define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
50#define SSH1_MSG_DEBUG 36 /* 0x24 */
51#define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
52#define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
53#define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
54#define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
55#define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
56#define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
57#define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
58
59#define SSH1_AUTH_TIS 5 /* 0x5 */
60#define SSH1_AUTH_CCARD 16 /* 0x10 */
61
62#define SSH1_PROTOFLAG_SCREEN_NUMBER 1 /* 0x1 */
b96dc54c 63/* Mask for protoflags we will echo back to server if seen */
32874aea 64#define SSH1_PROTOFLAGS_SUPPORTED 0 /* 0x1 */
65
66#define SSH2_MSG_DISCONNECT 1 /* 0x1 */
67#define SSH2_MSG_IGNORE 2 /* 0x2 */
68#define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
69#define SSH2_MSG_DEBUG 4 /* 0x4 */
70#define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
71#define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
72#define SSH2_MSG_KEXINIT 20 /* 0x14 */
73#define SSH2_MSG_NEWKEYS 21 /* 0x15 */
74#define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
75#define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
76#define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */
77#define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
78#define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
79#define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
80#define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
81#define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
82#define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
83#define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
84#define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
85#define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
761187b6 86#define SSH2_MSG_USERAUTH_INFO_REQUEST 60 /* 0x3c */
87#define SSH2_MSG_USERAUTH_INFO_RESPONSE 61 /* 0x3d */
32874aea 88#define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
89#define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
90#define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
91#define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
92#define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
93#define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
94#define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
95#define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
96#define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
97#define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
98#define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
99#define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
100#define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
101#define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
102
00db133f 103/*
104 * Packet type contexts, so that ssh2_pkt_type can correctly decode
105 * the ambiguous type numbers back into the correct type strings.
106 */
d1aaf71d 107#define SSH2_PKTCTX_DHGROUP 0x0001
00db133f 108#define SSH2_PKTCTX_DHGEX 0x0002
149d2abc 109#define SSH2_PKTCTX_KEX_MASK 0x000F
00db133f 110#define SSH2_PKTCTX_PUBLICKEY 0x0010
111#define SSH2_PKTCTX_PASSWORD 0x0020
112#define SSH2_PKTCTX_KBDINTER 0x0040
113#define SSH2_PKTCTX_AUTH_MASK 0x00F0
114
32874aea 115#define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
116#define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
117#define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
118#define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
119#define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
120#define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
121#define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
122#define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
123#define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
124#define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
125#define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
126#define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */
127#define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */
128#define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */
129#define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */
38c4a8da 130
131static const char *const ssh2_disconnect_reasons[] = {
132 NULL,
133 "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
134 "SSH_DISCONNECT_PROTOCOL_ERROR",
135 "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
136 "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
137 "SSH_DISCONNECT_MAC_ERROR",
138 "SSH_DISCONNECT_COMPRESSION_ERROR",
139 "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
140 "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
141 "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
142 "SSH_DISCONNECT_CONNECTION_LOST",
143 "SSH_DISCONNECT_BY_APPLICATION",
144 "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
145 "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
146 "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
147 "SSH_DISCONNECT_ILLEGAL_USER_NAME",
148};
9005f3ba 149
32874aea 150#define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
151#define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
152#define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
153#define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
d211621f 154
32874aea 155#define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
fb09bf1c 156
7d503c31 157/*
158 * Various remote-bug flags.
159 */
160#define BUG_CHOKES_ON_SSH1_IGNORE 1
161#define BUG_SSH2_HMAC 2
bd358db1 162#define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
0df73905 163#define BUG_CHOKES_ON_RSA 8
1dd353b5 164#define BUG_SSH2_RSA_PADDING 16
088bde77 165#define BUG_SSH2_DERIVEKEY 32
f382c87d 166#define BUG_SSH2_REKEY 64
dda87a28 167#define BUG_SSH2_PK_SESSIONID 128
bd358db1 168
00db133f 169#define translate(x) if (type == x) return #x
51470298 170#define translatec(x,ctx) if (type == x && (pkt_ctx & ctx)) return #x
ae9ae89f 171static char *ssh1_pkt_type(int type)
00db133f 172{
173 translate(SSH1_MSG_DISCONNECT);
174 translate(SSH1_SMSG_PUBLIC_KEY);
175 translate(SSH1_CMSG_SESSION_KEY);
176 translate(SSH1_CMSG_USER);
177 translate(SSH1_CMSG_AUTH_RSA);
178 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE);
179 translate(SSH1_CMSG_AUTH_RSA_RESPONSE);
180 translate(SSH1_CMSG_AUTH_PASSWORD);
181 translate(SSH1_CMSG_REQUEST_PTY);
182 translate(SSH1_CMSG_WINDOW_SIZE);
183 translate(SSH1_CMSG_EXEC_SHELL);
184 translate(SSH1_CMSG_EXEC_CMD);
185 translate(SSH1_SMSG_SUCCESS);
186 translate(SSH1_SMSG_FAILURE);
187 translate(SSH1_CMSG_STDIN_DATA);
188 translate(SSH1_SMSG_STDOUT_DATA);
189 translate(SSH1_SMSG_STDERR_DATA);
190 translate(SSH1_CMSG_EOF);
191 translate(SSH1_SMSG_EXIT_STATUS);
192 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION);
193 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE);
194 translate(SSH1_MSG_CHANNEL_DATA);
195 translate(SSH1_MSG_CHANNEL_CLOSE);
196 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION);
197 translate(SSH1_SMSG_X11_OPEN);
198 translate(SSH1_CMSG_PORT_FORWARD_REQUEST);
199 translate(SSH1_MSG_PORT_OPEN);
200 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING);
201 translate(SSH1_SMSG_AGENT_OPEN);
202 translate(SSH1_MSG_IGNORE);
203 translate(SSH1_CMSG_EXIT_CONFIRMATION);
204 translate(SSH1_CMSG_X11_REQUEST_FORWARDING);
205 translate(SSH1_CMSG_AUTH_RHOSTS_RSA);
206 translate(SSH1_MSG_DEBUG);
207 translate(SSH1_CMSG_REQUEST_COMPRESSION);
208 translate(SSH1_CMSG_AUTH_TIS);
209 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE);
210 translate(SSH1_CMSG_AUTH_TIS_RESPONSE);
211 translate(SSH1_CMSG_AUTH_CCARD);
212 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE);
213 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE);
214 return "unknown";
215}
ae9ae89f 216static char *ssh2_pkt_type(int pkt_ctx, int type)
00db133f 217{
218 translate(SSH2_MSG_DISCONNECT);
219 translate(SSH2_MSG_IGNORE);
220 translate(SSH2_MSG_UNIMPLEMENTED);
221 translate(SSH2_MSG_DEBUG);
222 translate(SSH2_MSG_SERVICE_REQUEST);
223 translate(SSH2_MSG_SERVICE_ACCEPT);
224 translate(SSH2_MSG_KEXINIT);
225 translate(SSH2_MSG_NEWKEYS);
d1aaf71d 226 translatec(SSH2_MSG_KEXDH_INIT, SSH2_PKTCTX_DHGROUP);
227 translatec(SSH2_MSG_KEXDH_REPLY, SSH2_PKTCTX_DHGROUP);
00db133f 228 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST, SSH2_PKTCTX_DHGEX);
229 translatec(SSH2_MSG_KEX_DH_GEX_GROUP, SSH2_PKTCTX_DHGEX);
230 translatec(SSH2_MSG_KEX_DH_GEX_INIT, SSH2_PKTCTX_DHGEX);
231 translatec(SSH2_MSG_KEX_DH_GEX_REPLY, SSH2_PKTCTX_DHGEX);
232 translate(SSH2_MSG_USERAUTH_REQUEST);
233 translate(SSH2_MSG_USERAUTH_FAILURE);
234 translate(SSH2_MSG_USERAUTH_SUCCESS);
235 translate(SSH2_MSG_USERAUTH_BANNER);
236 translatec(SSH2_MSG_USERAUTH_PK_OK, SSH2_PKTCTX_PUBLICKEY);
237 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, SSH2_PKTCTX_PASSWORD);
238 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST, SSH2_PKTCTX_KBDINTER);
239 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE, SSH2_PKTCTX_KBDINTER);
240 translate(SSH2_MSG_GLOBAL_REQUEST);
241 translate(SSH2_MSG_REQUEST_SUCCESS);
242 translate(SSH2_MSG_REQUEST_FAILURE);
243 translate(SSH2_MSG_CHANNEL_OPEN);
244 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
245 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE);
246 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
247 translate(SSH2_MSG_CHANNEL_DATA);
248 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA);
249 translate(SSH2_MSG_CHANNEL_EOF);
250 translate(SSH2_MSG_CHANNEL_CLOSE);
251 translate(SSH2_MSG_CHANNEL_REQUEST);
252 translate(SSH2_MSG_CHANNEL_SUCCESS);
253 translate(SSH2_MSG_CHANNEL_FAILURE);
254 return "unknown";
255}
256#undef translate
257#undef translatec
7d503c31 258
fb09bf1c 259#define GET_32BIT(cp) \
260 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
261 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
262 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
263 ((unsigned long)(unsigned char)(cp)[3]))
264
265#define PUT_32BIT(cp, value) { \
266 (cp)[0] = (unsigned char)((value) >> 24); \
267 (cp)[1] = (unsigned char)((value) >> 16); \
268 (cp)[2] = (unsigned char)((value) >> 8); \
269 (cp)[3] = (unsigned char)(value); }
270
9a10ecf4 271/* Enumeration values for fields in SSH-1 packets */
272enum {
273 PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR, PKT_BIGNUM,
274 /* These values are for communicating relevant semantics of
275 * fields to the packet logging code. */
276 PKTT_OTHER, PKTT_PASSWORD, PKTT_DATA
277};
972a41c8 278
acddebd9 279/*
280 * Coroutine mechanics for the sillier bits of the code. If these
281 * macros look impenetrable to you, you might find it helpful to
282 * read
283 *
284 * http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
285 *
286 * which explains the theory behind these macros.
b624d1e6 287 *
288 * In particular, if you are getting `case expression not constant'
289 * errors when building with MS Visual Studio, this is because MS's
290 * Edit and Continue debugging feature causes their compiler to
291 * violate ANSI C. To disable Edit and Continue debugging:
292 *
293 * - right-click ssh.c in the FileView
294 * - click Settings
295 * - select the C/C++ tab and the General category
296 * - under `Debug info:', select anything _other_ than `Program
297 * Database for Edit and Continue'.
acddebd9 298 */
51470298 299#define crBegin(v) { int *crLine = &v; switch(v) { case 0:;
300#define crState(t) \
301 struct t *s; \
3d88e64d 302 if (!ssh->t) ssh->t = snew(struct t); \
51470298 303 s = ssh->t;
304#define crFinish(z) } *crLine = 0; return (z); }
305#define crFinishV } *crLine = 0; return; }
374330e2 306#define crReturn(z) \
307 do {\
51470298 308 *crLine =__LINE__; return (z); case __LINE__:;\
374330e2 309 } while (0)
310#define crReturnV \
311 do {\
51470298 312 *crLine=__LINE__; return; case __LINE__:;\
374330e2 313 } while (0)
51470298 314#define crStop(z) do{ *crLine = 0; return (z); }while(0)
315#define crStopV do{ *crLine = 0; return; }while(0)
fb09bf1c 316#define crWaitUntil(c) do { crReturn(0); } while (!(c))
7cca0d81 317#define crWaitUntilV(c) do { crReturnV; } while (!(c))
374330e2 318
51470298 319typedef struct ssh_tag *Ssh;
ff3187f6 320struct Packet;
321
322static struct Packet *ssh2_pkt_init(int pkt_type);
323static void ssh2_pkt_addbool(struct Packet *, unsigned char value);
324static void ssh2_pkt_adduint32(struct Packet *, unsigned long value);
325static void ssh2_pkt_addstring_start(struct Packet *);
326static void ssh2_pkt_addstring_str(struct Packet *, char *data);
327static void ssh2_pkt_addstring_data(struct Packet *, char *data, int len);
328static void ssh2_pkt_addstring(struct Packet *, char *data);
d8baa528 329static unsigned char *ssh2_mpint_fmt(Bignum b, int *len);
ff3187f6 330static void ssh2_pkt_addmp(struct Packet *, Bignum b);
331static int ssh2_pkt_construct(Ssh, struct Packet *);
332static void ssh2_pkt_send(Ssh, struct Packet *);
590f6a5f 333static void ssh2_pkt_send_noqueue(Ssh, struct Packet *);
ff3187f6 334static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen,
335 struct Packet *pktin);
336static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
337 struct Packet *pktin);
3d63ca2e 338
5471d09a 339/*
340 * Buffer management constants. There are several of these for
341 * various different purposes:
342 *
343 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
344 * on a local data stream before we throttle the whole SSH
345 * connection (in SSH1 only). Throttling the whole connection is
346 * pretty drastic so we set this high in the hope it won't
347 * happen very often.
348 *
349 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
350 * on the SSH connection itself before we defensively throttle
351 * _all_ local data streams. This is pretty drastic too (though
352 * thankfully unlikely in SSH2 since the window mechanism should
353 * ensure that the server never has any need to throttle its end
354 * of the connection), so we set this high as well.
355 *
356 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
357 * channels.
358 */
359
360#define SSH1_BUFFER_LIMIT 32768
361#define SSH_MAX_BACKLOG 32768
362#define OUR_V2_WINSIZE 16384
954d5c5a 363#define OUR_V2_MAXPKT 0x4000UL
d74d141c 364
85cc02bb 365const static struct ssh_signkey *hostkey_algs[] = { &ssh_rsa, &ssh_dss };
e5574168 366
e0e1a00d 367static void *nullmac_make_context(void)
368{
369 return NULL;
370}
371static void nullmac_free_context(void *handle)
372{
373}
374static void nullmac_key(void *handle, unsigned char *key)
32874aea 375{
376}
e0e1a00d 377static void nullmac_generate(void *handle, unsigned char *blk, int len,
32874aea 378 unsigned long seq)
379{
380}
e0e1a00d 381static int nullmac_verify(void *handle, unsigned char *blk, int len,
382 unsigned long seq)
32874aea 383{
384 return 1;
385}
57476f6b 386const static struct ssh_mac ssh_mac_none = {
e0e1a00d 387 nullmac_make_context, nullmac_free_context, nullmac_key,
388 nullmac_generate, nullmac_verify, "none", 0
e5574168 389};
8b2715b2 390const static struct ssh_mac *macs[] = {
32874aea 391 &ssh_sha1, &ssh_md5, &ssh_mac_none
392};
8b2715b2 393const static struct ssh_mac *buggymacs[] = {
32874aea 394 &ssh_sha1_buggy, &ssh_md5, &ssh_mac_none
395};
e5574168 396
5366aed8 397static void *ssh_comp_none_init(void)
398{
399 return NULL;
400}
401static void ssh_comp_none_cleanup(void *handle)
32874aea 402{
403}
5366aed8 404static int ssh_comp_none_block(void *handle, unsigned char *block, int len,
32874aea 405 unsigned char **outblock, int *outlen)
406{
407 return 0;
408}
5366aed8 409static int ssh_comp_none_disable(void *handle)
32874aea 410{
4ba9b64b 411 return 0;
412}
57476f6b 413const static struct ssh_compress ssh_comp_none = {
4ba9b64b 414 "none",
5366aed8 415 ssh_comp_none_init, ssh_comp_none_cleanup, ssh_comp_none_block,
416 ssh_comp_none_init, ssh_comp_none_cleanup, ssh_comp_none_block,
417 ssh_comp_none_disable, NULL
e5574168 418};
4ba9b64b 419extern const struct ssh_compress ssh_zlib;
420const static struct ssh_compress *compressions[] = {
32874aea 421 &ssh_zlib, &ssh_comp_none
422};
374330e2 423
32874aea 424enum { /* channel types */
783415f8 425 CHAN_MAINSESSION,
426 CHAN_X11,
427 CHAN_AGENT,
bc240b21 428 CHAN_SOCKDATA,
429 CHAN_SOCKDATA_DORMANT /* one the remote hasn't confirmed */
783415f8 430};
431
dacbd0e8 432/*
433 * 2-3-4 tree storing channels.
434 */
435struct ssh_channel {
51470298 436 Ssh ssh; /* pointer back to main context */
d211621f 437 unsigned remoteid, localid;
dacbd0e8 438 int type;
64d6ff88 439 /* True if we opened this channel but server hasn't confirmed. */
440 int halfopen;
0357890f 441 /*
442 * In SSH1, this value contains four bits:
443 *
444 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
445 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
446 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
447 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
448 *
449 * A channel is completely finished with when all four bits are set.
450 */
dacbd0e8 451 int closes;
5471d09a 452 union {
453 struct ssh1_data_channel {
454 int throttling;
455 } v1;
456 struct ssh2_data_channel {
457 bufchain outbuffer;
458 unsigned remwindow, remmaxpkt;
459 unsigned locwindow;
460 } v2;
461 } v;
dacbd0e8 462 union {
32874aea 463 struct ssh_agent_channel {
464 unsigned char *message;
465 unsigned char msglen[4];
a03c9f9c 466 unsigned lensofar, totallen;
32874aea 467 } a;
468 struct ssh_x11_channel {
469 Socket s;
470 } x11;
d74d141c 471 struct ssh_pfd_channel {
472 Socket s;
473 } pfd;
dacbd0e8 474 } u;
475};
57476f6b 476
d74d141c 477/*
bc240b21 478 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
479 * 2 use this structure in different ways, reflecting SSH 2's
480 * altogether saner approach to port forwarding.
481 *
482 * In SSH 1, you arrange a remote forwarding by sending the server
483 * the remote port number, and the local destination host:port.
484 * When a connection comes in, the server sends you back that
485 * host:port pair, and you connect to it. This is a ready-made
486 * security hole if you're not on the ball: a malicious server
487 * could send you back _any_ host:port pair, so if you trustingly
488 * connect to the address it gives you then you've just opened the
489 * entire inside of your corporate network just by connecting
490 * through it to a dodgy SSH server. Hence, we must store a list of
491 * host:port pairs we _are_ trying to forward to, and reject a
492 * connection request from the server if it's not in the list.
493 *
494 * In SSH 2, each side of the connection minds its own business and
495 * doesn't send unnecessary information to the other. You arrange a
496 * remote forwarding by sending the server just the remote port
497 * number. When a connection comes in, the server tells you which
498 * of its ports was connected to; and _you_ have to remember what
499 * local host:port pair went with that port number.
500 *
06fadff5 501 * Hence, in SSH 1 this structure is indexed by destination
502 * host:port pair, whereas in SSH 2 it is indexed by source port.
d74d141c 503 */
fda2feb1 504struct ssh_portfwd; /* forward declaration */
505
d74d141c 506struct ssh_rportfwd {
bc240b21 507 unsigned sport, dport;
508 char dhost[256];
06fadff5 509 char *sportdesc;
fda2feb1 510 struct ssh_portfwd *pfrec;
d74d141c 511};
fda2feb1 512#define free_rportfwd(pf) ( \
513 ((pf) ? (sfree((pf)->sportdesc)) : (void)0 ), sfree(pf) )
514
515/*
516 * Separately to the rportfwd tree (which is for looking up port
517 * open requests from the server), a tree of _these_ structures is
518 * used to keep track of all the currently open port forwardings,
519 * so that we can reconfigure in mid-session if the user requests
520 * it.
521 */
522struct ssh_portfwd {
84328ddb 523 enum { DESTROY, KEEP, CREATE } status;
fda2feb1 524 int type;
525 unsigned sport, dport;
526 char *saddr, *daddr;
3fe92132 527 char *sserv, *dserv;
fda2feb1 528 struct ssh_rportfwd *remote;
05581745 529 int addressfamily;
fda2feb1 530 void *local;
531};
532#define free_portfwd(pf) ( \
3fe92132 533 ((pf) ? (sfree((pf)->saddr), sfree((pf)->daddr), \
534 sfree((pf)->sserv), sfree((pf)->dserv)) : (void)0 ), sfree(pf) )
d74d141c 535
57476f6b 536struct Packet {
537 long length;
95d2d262 538 long forcepad; /* Force padding to at least this length */
57476f6b 539 int type;
b09eaa88 540 unsigned long sequence;
57476f6b 541 unsigned char *data;
542 unsigned char *body;
543 long savedpos;
544 long maxlen;
9442dd57 545 long encrypted_len; /* for SSH2 total-size counting */
ff3187f6 546
547 /*
548 * State associated with packet logging
549 */
550 int logmode;
551 int nblanks;
552 struct logblank_t *blanks;
57476f6b 553};
554
1c1a7262 555static void ssh1_protocol(Ssh ssh, void *vin, int inlen,
ff3187f6 556 struct Packet *pktin);
1c1a7262 557static void ssh2_protocol(Ssh ssh, void *vin, int inlen,
ff3187f6 558 struct Packet *pktin);
b09eaa88 559static void ssh1_protocol_setup(Ssh ssh);
560static void ssh2_protocol_setup(Ssh ssh);
51470298 561static void ssh_size(void *handle, int width, int height);
562static void ssh_special(void *handle, Telnet_Special);
5471d09a 563static int ssh2_try_send(struct ssh_channel *c);
51470298 564static void ssh2_add_channel_data(struct ssh_channel *c, char *buf, int len);
565static void ssh_throttle_all(Ssh ssh, int enable, int bufsize);
5471d09a 566static void ssh2_set_window(struct ssh_channel *c, unsigned newwin);
51470298 567static int ssh_sendbuffer(void *handle);
ac934965 568static int ssh_do_close(Ssh ssh, int notify_exit);
ff3187f6 569static unsigned long ssh_pkt_getuint32(struct Packet *pkt);
570static int ssh2_pkt_getbool(struct Packet *pkt);
571static void ssh_pkt_getstring(struct Packet *pkt, char **p, int *length);
9442dd57 572static void ssh2_timer(void *ctx, long now);
1c1a7262 573static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
9442dd57 574 struct Packet *pktin);
57476f6b 575
51470298 576struct rdpkt1_state_tag {
57476f6b 577 long len, pad, biglen, to_read;
578 unsigned long realcrc, gotcrc;
579 unsigned char *p;
580 int i;
581 int chunk;
ff3187f6 582 struct Packet *pktin;
51470298 583};
57476f6b 584
51470298 585struct rdpkt2_state_tag {
960e736a 586 long len, pad, payload, packetlen, maclen;
587 int i;
588 int cipherblk;
589 unsigned long incoming_sequence;
ff3187f6 590 struct Packet *pktin;
51470298 591};
592
b09eaa88 593typedef void (*handler_fn_t)(Ssh ssh, struct Packet *pktin);
06fadff5 594typedef void (*chandler_fn_t)(Ssh ssh, struct Packet *pktin, void *ctx);
595
596struct queued_handler;
597struct queued_handler {
598 int msg1, msg2;
599 chandler_fn_t handler;
600 void *ctx;
601 struct queued_handler *next;
602};
b09eaa88 603
51470298 604struct ssh_tag {
605 const struct plug_function_table *fn;
606 /* the above field _must_ be first in the structure */
607
608 SHA_State exhash, exhashbase;
609
610 Socket s;
611
b9d7bcad 612 void *ldisc;
a8327734 613 void *logctx;
b9d7bcad 614
51470298 615 unsigned char session_key[32];
616 int v1_compressing;
617 int v1_remote_protoflags;
618 int v1_local_protoflags;
619 int agentfwd_enabled;
620 int X11_fwd_enabled;
621 int remote_bugs;
622 const struct ssh_cipher *cipher;
371e569c 623 void *v1_cipher_ctx;
0183b242 624 void *crcda_ctx;
51470298 625 const struct ssh2_cipher *cscipher, *sccipher;
371e569c 626 void *cs_cipher_ctx, *sc_cipher_ctx;
51470298 627 const struct ssh_mac *csmac, *scmac;
e0e1a00d 628 void *cs_mac_ctx, *sc_mac_ctx;
51470298 629 const struct ssh_compress *cscomp, *sccomp;
5366aed8 630 void *cs_comp_ctx, *sc_comp_ctx;
51470298 631 const struct ssh_kex *kex;
632 const struct ssh_signkey *hostkey;
633 unsigned char v2_session_id[20];
27cd7fc2 634 void *kex_ctx;
51470298 635
636 char *savedhost;
637 int savedport;
638 int send_ok;
639 int echoing, editing;
640
641 void *frontend;
642
db219738 643 int ospeed, ispeed; /* temporaries */
51470298 644 int term_width, term_height;
645
646 tree234 *channels; /* indexed by local id */
647 struct ssh_channel *mainchan; /* primary session channel */
648 int exitcode;
ac934965 649 int close_expected;
51470298 650
fda2feb1 651 tree234 *rportfwds, *portfwds;
51470298 652
653 enum {
654 SSH_STATE_PREPACKET,
655 SSH_STATE_BEFORE_SIZE,
656 SSH_STATE_INTERMED,
657 SSH_STATE_SESSION,
658 SSH_STATE_CLOSED
659 } state;
660
661 int size_needed, eof_needed;
662
590f6a5f 663 struct Packet **queue;
664 int queuelen, queuesize;
665 int queueing;
51470298 666 unsigned char *deferred_send_data;
667 int deferred_len, deferred_size;
668
669 /*
670 * Gross hack: pscp will try to start SFTP but fall back to
671 * scp1 if that fails. This variable is the means by which
672 * scp.c can reach into the SSH code and find out which one it
673 * got.
674 */
675 int fallback_cmd;
676
677 /*
678 * Used for username and password input.
679 */
680 char *userpass_input_buffer;
681 int userpass_input_buflen;
682 int userpass_input_bufpos;
683 int userpass_input_echo;
684
51470298 685 int pkt_ctx;
686
302121de 687 void *x11auth;
688
51470298 689 int version;
690 int v1_throttle_count;
691 int overall_bufsize;
692 int throttled_all;
693 int v1_stdout_throttling;
a8756193 694 unsigned long v2_outgoing_sequence;
51470298 695
696 int ssh1_rdpkt_crstate;
697 int ssh2_rdpkt_crstate;
698 int do_ssh_init_crstate;
699 int ssh_gotdata_crstate;
51470298 700 int do_ssh1_login_crstate;
b09eaa88 701 int do_ssh1_connection_crstate;
51470298 702 int do_ssh2_transport_crstate;
703 int do_ssh2_authconn_crstate;
704
705 void *do_ssh_init_state;
706 void *do_ssh1_login_state;
707 void *do_ssh2_transport_state;
708 void *do_ssh2_authconn_state;
709
710 struct rdpkt1_state_tag rdpkt1_state;
711 struct rdpkt2_state_tag rdpkt2_state;
712
b09eaa88 713 /* ssh1 and ssh2 use this for different things, but both use it */
714 int protocol_initial_phase_done;
715
1c1a7262 716 void (*protocol) (Ssh ssh, void *vin, int inlen,
ff3187f6 717 struct Packet *pkt);
718 struct Packet *(*s_rdpkt) (Ssh ssh, unsigned char **data, int *datalen);
86916870 719
720 /*
721 * We maintain a full _copy_ of a Config structure here, not
722 * merely a pointer to it. That way, when we're passed a new
723 * one for reconfiguration, we can check the differences and
724 * potentially reconfigure port forwardings etc in mid-session.
725 */
726 Config cfg;
839f10db 727
728 /*
729 * Used to transfer data back from async agent callbacks.
730 */
731 void *agent_response;
732 int agent_response_len;
b09eaa88 733
734 /*
735 * Dispatch table for packet types that we may have to deal
736 * with at any time.
737 */
738 handler_fn_t packet_dispatch[256];
39934deb 739
740 /*
06fadff5 741 * Queues of one-off handler functions for success/failure
742 * indications from a request.
743 */
744 struct queued_handler *qhead, *qtail;
745
746 /*
39934deb 747 * This module deals with sending keepalives.
748 */
749 Pinger pinger;
9442dd57 750
751 /*
752 * Track incoming and outgoing data sizes and time, for
753 * size-based rekeys.
754 */
755 unsigned long incoming_data_size, outgoing_data_size, deferred_data_size;
d57f70af 756 unsigned long max_data_size;
9442dd57 757 int kex_in_progress;
e6c1536e 758 long next_rekey, last_rekey;
e13bba36 759 char *deferred_rekey_reason; /* points to STATIC string; don't free */
51470298 760};
960e736a 761
382908ad 762#define logevent(s) logevent(ssh->frontend, s)
a8327734 763
764/* logevent, only printf-formatted. */
cbe2d68f 765static void logeventf(Ssh ssh, const char *fmt, ...)
a8327734 766{
767 va_list ap;
57356d63 768 char *buf;
a8327734 769
770 va_start(ap, fmt);
57356d63 771 buf = dupvprintf(fmt, ap);
a8327734 772 va_end(ap);
57356d63 773 logevent(buf);
57356d63 774 sfree(buf);
a8327734 775}
776
6b5cf8b4 777#define bombout(msg) \
778 do { \
779 char *text = dupprintf msg; \
ac934965 780 ssh_do_close(ssh, FALSE); \
6b5cf8b4 781 logevent(text); \
782 connection_fatal(ssh->frontend, "%s", text); \
783 sfree(text); \
784 } while (0)
a8327734 785
9a10ecf4 786/* Functions to leave bits out of the SSH packet log file. */
787
ff3187f6 788static void dont_log_password(Ssh ssh, struct Packet *pkt, int blanktype)
9a10ecf4 789{
790 if (ssh->cfg.logomitpass)
ff3187f6 791 pkt->logmode = blanktype;
9a10ecf4 792}
793
ff3187f6 794static void dont_log_data(Ssh ssh, struct Packet *pkt, int blanktype)
9a10ecf4 795{
796 if (ssh->cfg.logomitdata)
ff3187f6 797 pkt->logmode = blanktype;
9a10ecf4 798}
799
ff3187f6 800static void end_log_omission(Ssh ssh, struct Packet *pkt)
9a10ecf4 801{
ff3187f6 802 pkt->logmode = PKTLOG_EMIT;
9a10ecf4 803}
804
32874aea 805static int ssh_channelcmp(void *av, void *bv)
806{
807 struct ssh_channel *a = (struct ssh_channel *) av;
808 struct ssh_channel *b = (struct ssh_channel *) bv;
809 if (a->localid < b->localid)
810 return -1;
811 if (a->localid > b->localid)
812 return +1;
dacbd0e8 813 return 0;
814}
32874aea 815static int ssh_channelfind(void *av, void *bv)
816{
817 unsigned *a = (unsigned *) av;
818 struct ssh_channel *b = (struct ssh_channel *) bv;
819 if (*a < b->localid)
820 return -1;
821 if (*a > b->localid)
822 return +1;
dacbd0e8 823 return 0;
824}
825
bc240b21 826static int ssh_rportcmp_ssh1(void *av, void *bv)
d74d141c 827{
828 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
829 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
830 int i;
bc240b21 831 if ( (i = strcmp(a->dhost, b->dhost)) != 0)
d74d141c 832 return i < 0 ? -1 : +1;
bc240b21 833 if (a->dport > b->dport)
834 return +1;
835 if (a->dport < b->dport)
836 return -1;
837 return 0;
838}
839
840static int ssh_rportcmp_ssh2(void *av, void *bv)
841{
842 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
843 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
cdcbdf3b 844
bc240b21 845 if (a->sport > b->sport)
d74d141c 846 return +1;
bc240b21 847 if (a->sport < b->sport)
848 return -1;
d74d141c 849 return 0;
850}
851
fda2feb1 852/*
853 * Special form of strcmp which can cope with NULL inputs. NULL is
854 * defined to sort before even the empty string.
855 */
856static int nullstrcmp(const char *a, const char *b)
857{
858 if (a == NULL && b == NULL)
859 return 0;
860 if (a == NULL)
861 return -1;
862 if (b == NULL)
863 return +1;
864 return strcmp(a, b);
865}
866
867static int ssh_portcmp(void *av, void *bv)
868{
869 struct ssh_portfwd *a = (struct ssh_portfwd *) av;
870 struct ssh_portfwd *b = (struct ssh_portfwd *) bv;
871 int i;
872 if (a->type > b->type)
873 return +1;
874 if (a->type < b->type)
875 return -1;
84328ddb 876 if (a->addressfamily > b->addressfamily)
877 return +1;
878 if (a->addressfamily < b->addressfamily)
879 return -1;
fda2feb1 880 if ( (i = nullstrcmp(a->saddr, b->saddr)) != 0)
881 return i < 0 ? -1 : +1;
882 if (a->sport > b->sport)
883 return +1;
884 if (a->sport < b->sport)
885 return -1;
886 if (a->type != 'D') {
887 if ( (i = nullstrcmp(a->daddr, b->daddr)) != 0)
888 return i < 0 ? -1 : +1;
889 if (a->dport > b->dport)
890 return +1;
891 if (a->dport < b->dport)
892 return -1;
893 }
894 return 0;
895}
896
51470298 897static int alloc_channel_id(Ssh ssh)
32874aea 898{
260f3dec 899 const unsigned CHANNEL_NUMBER_OFFSET = 256;
900 unsigned low, high, mid;
d2371c81 901 int tsize;
902 struct ssh_channel *c;
903
904 /*
905 * First-fit allocation of channel numbers: always pick the
906 * lowest unused one. To do this, binary-search using the
907 * counted B-tree to find the largest channel ID which is in a
908 * contiguous sequence from the beginning. (Precisely
909 * everything in that sequence must have ID equal to its tree
910 * index plus CHANNEL_NUMBER_OFFSET.)
911 */
51470298 912 tsize = count234(ssh->channels);
d2371c81 913
32874aea 914 low = -1;
915 high = tsize;
d2371c81 916 while (high - low > 1) {
917 mid = (high + low) / 2;
51470298 918 c = index234(ssh->channels, mid);
d2371c81 919 if (c->localid == mid + CHANNEL_NUMBER_OFFSET)
920 low = mid; /* this one is fine */
921 else
922 high = mid; /* this one is past it */
923 }
924 /*
925 * Now low points to either -1, or the tree index of the
926 * largest ID in the initial sequence.
927 */
928 {
929 unsigned i = low + 1 + CHANNEL_NUMBER_OFFSET;
51470298 930 assert(NULL == find234(ssh->channels, &i, ssh_channelfind));
d2371c81 931 }
932 return low + 1 + CHANNEL_NUMBER_OFFSET;
933}
934
9fab77dc 935static void c_write(Ssh ssh, const char *buf, int len)
32874aea 936{
67779be7 937 if ((flags & FLAG_STDERR)) {
32874aea 938 int i;
939 for (i = 0; i < len; i++)
940 if (buf[i] != '\r')
941 fputc(buf[i], stderr);
fb09bf1c 942 return;
943 }
51470298 944 from_backend(ssh->frontend, 1, buf, len);
3bdaf79d 945}
946
9fab77dc 947static void c_write_untrusted(Ssh ssh, const char *buf, int len)
32874aea 948{
a209e957 949 int i;
950 for (i = 0; i < len; i++) {
32874aea 951 if (buf[i] == '\n')
51470298 952 c_write(ssh, "\r\n", 2);
32874aea 953 else if ((buf[i] & 0x60) || (buf[i] == '\r'))
51470298 954 c_write(ssh, buf + i, 1);
a209e957 955 }
956}
957
9fab77dc 958static void c_write_str(Ssh ssh, const char *buf)
32874aea 959{
51470298 960 c_write(ssh, buf, strlen(buf));
1408a877 961}
962
ff3187f6 963static void ssh_free_packet(struct Packet *pkt)
964{
965 sfree(pkt->data);
966 sfree(pkt);
967}
968static struct Packet *ssh_new_packet(void)
969{
970 struct Packet *pkt = snew(struct Packet);
971
972 pkt->data = NULL;
973 pkt->maxlen = 0;
974 pkt->logmode = PKTLOG_EMIT;
975 pkt->nblanks = 0;
976 pkt->blanks = NULL;
977
978 return pkt;
979}
980
fb09bf1c 981/*
982 * Collect incoming data in the incoming packet buffer.
e5574168 983 * Decipher and verify the packet when it is completely read.
984 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
fb09bf1c 985 * Update the *data and *datalen variables.
ff3187f6 986 * Return a Packet structure when a packet is completed.
fb09bf1c 987 */
ff3187f6 988static struct Packet *ssh1_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
fb09bf1c 989{
51470298 990 struct rdpkt1_state_tag *st = &ssh->rdpkt1_state;
374330e2 991
51470298 992 crBegin(ssh->ssh1_rdpkt_crstate);
374330e2 993
ff3187f6 994 st->pktin = ssh_new_packet();
995
996 st->pktin->type = 0;
997 st->pktin->length = 0;
374330e2 998
57476f6b 999 for (st->i = st->len = 0; st->i < 4; st->i++) {
fb09bf1c 1000 while ((*datalen) == 0)
ff3187f6 1001 crReturn(NULL);
57476f6b 1002 st->len = (st->len << 8) + **data;
fb09bf1c 1003 (*data)++, (*datalen)--;
1004 }
374330e2 1005
57476f6b 1006 st->pad = 8 - (st->len % 8);
1007 st->biglen = st->len + st->pad;
ff3187f6 1008 st->pktin->length = st->len - 5;
fb09bf1c 1009
ae0500e5 1010 if (st->biglen < 0) {
1011 bombout(("Extremely large packet length from server suggests"
1012 " data stream corruption"));
ff3187f6 1013 ssh_free_packet(st->pktin);
1014 crStop(NULL);
ae0500e5 1015 }
1016
ff3187f6 1017 st->pktin->maxlen = st->biglen;
1018 st->pktin->data = snewn(st->biglen + APIEXTRA, unsigned char);
374330e2 1019
57476f6b 1020 st->to_read = st->biglen;
ff3187f6 1021 st->p = st->pktin->data;
57476f6b 1022 while (st->to_read > 0) {
32874aea 1023 st->chunk = st->to_read;
fb09bf1c 1024 while ((*datalen) == 0)
ff3187f6 1025 crReturn(NULL);
57476f6b 1026 if (st->chunk > (*datalen))
1027 st->chunk = (*datalen);
1028 memcpy(st->p, *data, st->chunk);
1029 *data += st->chunk;
1030 *datalen -= st->chunk;
1031 st->p += st->chunk;
1032 st->to_read -= st->chunk;
fb09bf1c 1033 }
374330e2 1034
ff3187f6 1035 if (ssh->cipher && detect_attack(ssh->crcda_ctx, st->pktin->data,
0183b242 1036 st->biglen, NULL)) {
6b5cf8b4 1037 bombout(("Network attack (CRC compensation) detected!"));
ff3187f6 1038 ssh_free_packet(st->pktin);
1039 crStop(NULL);
9a3a93a5 1040 }
1041
51470298 1042 if (ssh->cipher)
ff3187f6 1043 ssh->cipher->decrypt(ssh->v1_cipher_ctx, st->pktin->data, st->biglen);
374330e2 1044
ff3187f6 1045 st->realcrc = crc32_compute(st->pktin->data, st->biglen - 4);
1046 st->gotcrc = GET_32BIT(st->pktin->data + st->biglen - 4);
57476f6b 1047 if (st->gotcrc != st->realcrc) {
6b5cf8b4 1048 bombout(("Incorrect CRC received on packet"));
ff3187f6 1049 ssh_free_packet(st->pktin);
1050 crStop(NULL);
fb09bf1c 1051 }
572f871e 1052
ff3187f6 1053 st->pktin->body = st->pktin->data + st->pad + 1;
1054 st->pktin->savedpos = 0;
4ba9b64b 1055
51470298 1056 if (ssh->v1_compressing) {
4ba9b64b 1057 unsigned char *decompblk;
1058 int decomplen;
36b8d9bb 1059 if (!zlib_decompress_block(ssh->sc_comp_ctx,
ff3187f6 1060 st->pktin->body - 1, st->pktin->length + 1,
36b8d9bb 1061 &decompblk, &decomplen)) {
1062 bombout(("Zlib decompression encountered invalid data"));
ff3187f6 1063 ssh_free_packet(st->pktin);
1064 crStop(NULL);
36b8d9bb 1065 }
4ba9b64b 1066
ff3187f6 1067 if (st->pktin->maxlen < st->pad + decomplen) {
1068 st->pktin->maxlen = st->pad + decomplen;
1069 st->pktin->data = sresize(st->pktin->data,
1070 st->pktin->maxlen + APIEXTRA,
3d88e64d 1071 unsigned char);
ff3187f6 1072 st->pktin->body = st->pktin->data + st->pad + 1;
4ba9b64b 1073 }
1074
ff3187f6 1075 memcpy(st->pktin->body - 1, decompblk, decomplen);
dcbde236 1076 sfree(decompblk);
ff3187f6 1077 st->pktin->length = decomplen - 1;
4ba9b64b 1078 }
1079
ff3187f6 1080 st->pktin->type = st->pktin->body[-1];
00db133f 1081
9a10ecf4 1082 /*
1083 * Log incoming packet, possibly omitting sensitive fields.
1084 */
1085 if (ssh->logctx) {
1086 int nblanks = 0;
1087 struct logblank_t blank;
1088 if (ssh->cfg.logomitdata) {
1089 int do_blank = FALSE, blank_prefix = 0;
1090 /* "Session data" packets - omit the data field */
ff3187f6 1091 if ((st->pktin->type == SSH1_SMSG_STDOUT_DATA) ||
1092 (st->pktin->type == SSH1_SMSG_STDERR_DATA)) {
9a10ecf4 1093 do_blank = TRUE; blank_prefix = 0;
ff3187f6 1094 } else if (st->pktin->type == SSH1_MSG_CHANNEL_DATA) {
9a10ecf4 1095 do_blank = TRUE; blank_prefix = 4;
1096 }
1097 if (do_blank) {
1098 blank.offset = blank_prefix;
ff3187f6 1099 blank.len = st->pktin->length;
9a10ecf4 1100 blank.type = PKTLOG_OMIT;
1101 nblanks = 1;
1102 }
1103 }
a8327734 1104 log_packet(ssh->logctx,
ff3187f6 1105 PKT_INCOMING, st->pktin->type,
1106 ssh1_pkt_type(st->pktin->type),
1107 st->pktin->body, st->pktin->length,
9a10ecf4 1108 nblanks, &blank);
1109 }
00db133f 1110
ff3187f6 1111 crFinish(st->pktin);
fb09bf1c 1112}
1113
ff3187f6 1114static struct Packet *ssh2_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
e5574168 1115{
51470298 1116 struct rdpkt2_state_tag *st = &ssh->rdpkt2_state;
e5574168 1117
51470298 1118 crBegin(ssh->ssh2_rdpkt_crstate);
e5574168 1119
ff3187f6 1120 st->pktin = ssh_new_packet();
1121
1122 st->pktin->type = 0;
1123 st->pktin->length = 0;
51470298 1124 if (ssh->sccipher)
1125 st->cipherblk = ssh->sccipher->blksize;
e5574168 1126 else
32874aea 1127 st->cipherblk = 8;
960e736a 1128 if (st->cipherblk < 8)
32874aea 1129 st->cipherblk = 8;
960e736a 1130
ff3187f6 1131 st->pktin->data = snewn(st->cipherblk + APIEXTRA, unsigned char);
e5574168 1132
1133 /*
1134 * Acquire and decrypt the first block of the packet. This will
1135 * contain the length and padding details.
1136 */
32874aea 1137 for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) {
e5574168 1138 while ((*datalen) == 0)
ff3187f6 1139 crReturn(NULL);
1140 st->pktin->data[st->i] = *(*data)++;
32874aea 1141 (*datalen)--;
e5574168 1142 }
4252c9cc 1143
51470298 1144 if (ssh->sccipher)
371e569c 1145 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
ff3187f6 1146 st->pktin->data, st->cipherblk);
e5574168 1147
1148 /*
1149 * Now get the length and padding figures.
1150 */
ff3187f6 1151 st->len = GET_32BIT(st->pktin->data);
1152 st->pad = st->pktin->data[4];
e5574168 1153
1154 /*
717dc483 1155 * _Completely_ silly lengths should be stomped on before they
1156 * do us any more damage.
1157 */
1158 if (st->len < 0 || st->pad < 0 || st->len + st->pad < 0) {
6b5cf8b4 1159 bombout(("Incoming packet was garbled on decryption"));
ff3187f6 1160 ssh_free_packet(st->pktin);
1161 crStop(NULL);
717dc483 1162 }
1163
1164 /*
e5574168 1165 * This enables us to deduce the payload length.
1166 */
960e736a 1167 st->payload = st->len - st->pad - 1;
e5574168 1168
ff3187f6 1169 st->pktin->length = st->payload + 5;
e5574168 1170
1171 /*
1172 * So now we can work out the total packet length.
1173 */
960e736a 1174 st->packetlen = st->len + 4;
51470298 1175 st->maclen = ssh->scmac ? ssh->scmac->len : 0;
e5574168 1176
1177 /*
ff3187f6 1178 * Allocate memory for the rest of the packet.
e5574168 1179 */
ff3187f6 1180 st->pktin->maxlen = st->packetlen + st->maclen;
1181 st->pktin->data = sresize(st->pktin->data,
1182 st->pktin->maxlen + APIEXTRA,
1183 unsigned char);
e5574168 1184
1185 /*
1186 * Read and decrypt the remainder of the packet.
1187 */
32874aea 1188 for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen;
1189 st->i++) {
e5574168 1190 while ((*datalen) == 0)
ff3187f6 1191 crReturn(NULL);
1192 st->pktin->data[st->i] = *(*data)++;
32874aea 1193 (*datalen)--;
e5574168 1194 }
1195 /* Decrypt everything _except_ the MAC. */
51470298 1196 if (ssh->sccipher)
371e569c 1197 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
ff3187f6 1198 st->pktin->data + st->cipherblk,
51470298 1199 st->packetlen - st->cipherblk);
e5574168 1200
9442dd57 1201 st->pktin->encrypted_len = st->packetlen;
1202
e5574168 1203 /*
1204 * Check the MAC.
1205 */
51470298 1206 if (ssh->scmac
ff3187f6 1207 && !ssh->scmac->verify(ssh->sc_mac_ctx, st->pktin->data, st->len + 4,
51470298 1208 st->incoming_sequence)) {
6b5cf8b4 1209 bombout(("Incorrect MAC received on packet"));
ff3187f6 1210 ssh_free_packet(st->pktin);
1211 crStop(NULL);
8d5de777 1212 }
b09eaa88 1213
1214 st->pktin->sequence = st->incoming_sequence++;
e5574168 1215
4ba9b64b 1216 /*
1217 * Decompress packet payload.
1218 */
1219 {
1220 unsigned char *newpayload;
1221 int newlen;
51470298 1222 if (ssh->sccomp &&
5366aed8 1223 ssh->sccomp->decompress(ssh->sc_comp_ctx,
ff3187f6 1224 st->pktin->data + 5, st->pktin->length - 5,
51470298 1225 &newpayload, &newlen)) {
ff3187f6 1226 if (st->pktin->maxlen < newlen + 5) {
1227 st->pktin->maxlen = newlen + 5;
1228 st->pktin->data = sresize(st->pktin->data,
1229 st->pktin->maxlen + APIEXTRA,
3d88e64d 1230 unsigned char);
4ba9b64b 1231 }
ff3187f6 1232 st->pktin->length = 5 + newlen;
1233 memcpy(st->pktin->data + 5, newpayload, newlen);
dcbde236 1234 sfree(newpayload);
4ba9b64b 1235 }
1236 }
1237
ff3187f6 1238 st->pktin->savedpos = 6;
1239 st->pktin->body = st->pktin->data;
1240 st->pktin->type = st->pktin->data[5];
e5574168 1241
9a10ecf4 1242 /*
1243 * Log incoming packet, possibly omitting sensitive fields.
1244 */
1245 if (ssh->logctx) {
1246 int nblanks = 0;
1247 struct logblank_t blank;
1248 if (ssh->cfg.logomitdata) {
1249 int do_blank = FALSE, blank_prefix = 0;
1250 /* "Session data" packets - omit the data field */
ff3187f6 1251 if (st->pktin->type == SSH2_MSG_CHANNEL_DATA) {
9a10ecf4 1252 do_blank = TRUE; blank_prefix = 4;
ff3187f6 1253 } else if (st->pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
9a10ecf4 1254 do_blank = TRUE; blank_prefix = 8;
1255 }
1256 if (do_blank) {
1257 blank.offset = blank_prefix;
ff3187f6 1258 blank.len = (st->pktin->length-6) - blank_prefix;
9a10ecf4 1259 blank.type = PKTLOG_OMIT;
1260 nblanks = 1;
1261 }
1262 }
ff3187f6 1263 log_packet(ssh->logctx, PKT_INCOMING, st->pktin->type,
1264 ssh2_pkt_type(ssh->pkt_ctx, st->pktin->type),
1265 st->pktin->data+6, st->pktin->length-6,
9a10ecf4 1266 nblanks, &blank);
1267 }
00db133f 1268
ff3187f6 1269 crFinish(st->pktin);
e5574168 1270}
1271
ff3187f6 1272static void ssh1_pktout_size(struct Packet *pkt, int len)
32874aea 1273{
374330e2 1274 int pad, biglen;
1275
1276 len += 5; /* type and CRC */
32874aea 1277 pad = 8 - (len % 8);
374330e2 1278 biglen = len + pad;
1279
ff3187f6 1280 pkt->length = len - 5;
1281 if (pkt->maxlen < biglen) {
1282 pkt->maxlen = biglen;
1283 pkt->data = sresize(pkt->data, biglen + 4 + APIEXTRA, unsigned char);
374330e2 1284 }
ff3187f6 1285 pkt->body = pkt->data + 4 + pad + 1;
4ba9b64b 1286}
374330e2 1287
ff3187f6 1288static struct Packet *s_wrpkt_start(int type, int len)
32874aea 1289{
ff3187f6 1290 struct Packet *pkt = ssh_new_packet();
1291 ssh1_pktout_size(pkt, len);
1292 pkt->type = type;
9a10ecf4 1293 /* Initialise log omission state */
ff3187f6 1294 pkt->nblanks = 0;
1295 pkt->blanks = NULL;
1296 return pkt;
374330e2 1297}
1298
ff3187f6 1299static int s_wrpkt_prepare(Ssh ssh, struct Packet *pkt)
32874aea 1300{
fd7a4aad 1301 int pad, biglen, i;
374330e2 1302 unsigned long crc;
fd7a4aad 1303#ifdef __SC__
1304 /*
1305 * XXX various versions of SC (including 8.8.4) screw up the
1306 * register allocation in this function and use the same register
1307 * (D6) for len and as a temporary, with predictable results. The
1308 * following sledgehammer prevents this.
1309 */
1310 volatile
1311#endif
1312 int len;
374330e2 1313
ff3187f6 1314 pkt->body[-1] = pkt->type;
4ba9b64b 1315
a8327734 1316 if (ssh->logctx)
ff3187f6 1317 log_packet(ssh->logctx, PKT_OUTGOING, pkt->type,
1318 ssh1_pkt_type(pkt->type),
1319 pkt->body, pkt->length,
1320 pkt->nblanks, pkt->blanks);
1321 sfree(pkt->blanks); pkt->blanks = NULL;
1322 pkt->nblanks = 0;
00db133f 1323
51470298 1324 if (ssh->v1_compressing) {
4ba9b64b 1325 unsigned char *compblk;
1326 int complen;
5366aed8 1327 zlib_compress_block(ssh->cs_comp_ctx,
ff3187f6 1328 pkt->body - 1, pkt->length + 1,
4ba9b64b 1329 &compblk, &complen);
ff3187f6 1330 ssh1_pktout_size(pkt, complen - 1);
1331 memcpy(pkt->body - 1, compblk, complen);
dcbde236 1332 sfree(compblk);
4ba9b64b 1333 }
1334
ff3187f6 1335 len = pkt->length + 5; /* type and CRC */
32874aea 1336 pad = 8 - (len % 8);
374330e2 1337 biglen = len + pad;
1338
32874aea 1339 for (i = 0; i < pad; i++)
ff3187f6 1340 pkt->data[i + 4] = random_byte();
1341 crc = crc32_compute(pkt->data + 4, biglen - 4);
1342 PUT_32BIT(pkt->data + biglen, crc);
1343 PUT_32BIT(pkt->data, len);
374330e2 1344
51470298 1345 if (ssh->cipher)
ff3187f6 1346 ssh->cipher->encrypt(ssh->v1_cipher_ctx, pkt->data + 4, biglen);
374330e2 1347
32874aea 1348 return biglen + 4;
39065bed 1349}
1350
ff3187f6 1351static void s_wrpkt(Ssh ssh, struct Packet *pkt)
32874aea 1352{
5471d09a 1353 int len, backlog;
ff3187f6 1354 len = s_wrpkt_prepare(ssh, pkt);
1355 backlog = sk_write(ssh->s, (char *)pkt->data, len);
5471d09a 1356 if (backlog > SSH_MAX_BACKLOG)
51470298 1357 ssh_throttle_all(ssh, 1, backlog);
39065bed 1358}
1359
ff3187f6 1360static void s_wrpkt_defer(Ssh ssh, struct Packet *pkt)
32874aea 1361{
39065bed 1362 int len;
ff3187f6 1363 len = s_wrpkt_prepare(ssh, pkt);
51470298 1364 if (ssh->deferred_len + len > ssh->deferred_size) {
1365 ssh->deferred_size = ssh->deferred_len + len + 128;
3d88e64d 1366 ssh->deferred_send_data = sresize(ssh->deferred_send_data,
1367 ssh->deferred_size,
1368 unsigned char);
39065bed 1369 }
ff3187f6 1370 memcpy(ssh->deferred_send_data + ssh->deferred_len, pkt->data, len);
51470298 1371 ssh->deferred_len += len;
374330e2 1372}
1373
fb09bf1c 1374/*
39065bed 1375 * Construct a packet with the specified contents.
fb09bf1c 1376 */
ff3187f6 1377static struct Packet *construct_packet(Ssh ssh, int pkttype,
1378 va_list ap1, va_list ap2)
fb09bf1c 1379{
fb09bf1c 1380 unsigned char *p, *argp, argchar;
1381 unsigned long argint;
1382 int pktlen, argtype, arglen;
7cca0d81 1383 Bignum bn;
ff3187f6 1384 struct Packet *pkt;
fb09bf1c 1385
1386 pktlen = 0;
39065bed 1387 while ((argtype = va_arg(ap1, int)) != PKT_END) {
fb09bf1c 1388 switch (argtype) {
1389 case PKT_INT:
39065bed 1390 (void) va_arg(ap1, int);
fb09bf1c 1391 pktlen += 4;
1392 break;
1393 case PKT_CHAR:
1ec39246 1394 (void) va_arg(ap1, int);
fb09bf1c 1395 pktlen++;
1396 break;
1397 case PKT_DATA:
39065bed 1398 (void) va_arg(ap1, unsigned char *);
1399 arglen = va_arg(ap1, int);
fb09bf1c 1400 pktlen += arglen;
1401 break;
1402 case PKT_STR:
39065bed 1403 argp = va_arg(ap1, unsigned char *);
d8baa528 1404 arglen = strlen((char *)argp);
fb09bf1c 1405 pktlen += 4 + arglen;
1406 break;
7cca0d81 1407 case PKT_BIGNUM:
39065bed 1408 bn = va_arg(ap1, Bignum);
32874aea 1409 pktlen += ssh1_bignum_length(bn);
7cca0d81 1410 break;
9a10ecf4 1411 case PKTT_PASSWORD:
1412 case PKTT_DATA:
1413 case PKTT_OTHER:
1414 /* ignore this pass */
1415 break;
fb09bf1c 1416 default:
1417 assert(0);
1418 }
1419 }
fb09bf1c 1420
ff3187f6 1421 pkt = s_wrpkt_start(pkttype, pktlen);
1422 p = pkt->body;
fb09bf1c 1423
39065bed 1424 while ((argtype = va_arg(ap2, int)) != PKT_END) {
ff3187f6 1425 int offset = p - pkt->body, len = 0;
fb09bf1c 1426 switch (argtype) {
9a10ecf4 1427 /* Actual fields in the packet */
fb09bf1c 1428 case PKT_INT:
39065bed 1429 argint = va_arg(ap2, int);
fb09bf1c 1430 PUT_32BIT(p, argint);
9a10ecf4 1431 len = 4;
fb09bf1c 1432 break;
1433 case PKT_CHAR:
1ec39246 1434 argchar = (unsigned char) va_arg(ap2, int);
fb09bf1c 1435 *p = argchar;
9a10ecf4 1436 len = 1;
fb09bf1c 1437 break;
1438 case PKT_DATA:
39065bed 1439 argp = va_arg(ap2, unsigned char *);
1440 arglen = va_arg(ap2, int);
fb09bf1c 1441 memcpy(p, argp, arglen);
9a10ecf4 1442 len = arglen;
fb09bf1c 1443 break;
1444 case PKT_STR:
39065bed 1445 argp = va_arg(ap2, unsigned char *);
d8baa528 1446 arglen = strlen((char *)argp);
fb09bf1c 1447 PUT_32BIT(p, arglen);
1448 memcpy(p + 4, argp, arglen);
9a10ecf4 1449 len = arglen + 4;
fb09bf1c 1450 break;
7cca0d81 1451 case PKT_BIGNUM:
39065bed 1452 bn = va_arg(ap2, Bignum);
9a10ecf4 1453 len = ssh1_write_bignum(p, bn);
1454 break;
1455 /* Tokens for modifications to packet logging */
1456 case PKTT_PASSWORD:
ff3187f6 1457 dont_log_password(ssh, pkt, PKTLOG_BLANK);
9a10ecf4 1458 break;
1459 case PKTT_DATA:
ff3187f6 1460 dont_log_data(ssh, pkt, PKTLOG_OMIT);
7cca0d81 1461 break;
9a10ecf4 1462 case PKTT_OTHER:
ff3187f6 1463 end_log_omission(ssh, pkt);
9a10ecf4 1464 break;
1465 }
1466 p += len;
1467 /* Deal with logfile omission, if required. */
ff3187f6 1468 if (len && (pkt->logmode != PKTLOG_EMIT)) {
1469 pkt->nblanks++;
1470 pkt->blanks = sresize(pkt->blanks, pkt->nblanks,
1471 struct logblank_t);
1472 pkt->blanks[pkt->nblanks-1].offset = offset;
1473 pkt->blanks[pkt->nblanks-1].len = len;
1474 pkt->blanks[pkt->nblanks-1].type = pkt->logmode;
fb09bf1c 1475 }
1476 }
ff3187f6 1477
1478 return pkt;
39065bed 1479}
fb09bf1c 1480
51470298 1481static void send_packet(Ssh ssh, int pkttype, ...)
32874aea 1482{
ff3187f6 1483 struct Packet *pkt;
39065bed 1484 va_list ap1, ap2;
1485 va_start(ap1, pkttype);
1486 va_start(ap2, pkttype);
ff3187f6 1487 pkt = construct_packet(ssh, pkttype, ap1, ap2);
1488 va_end(ap2);
1489 va_end(ap1);
1490 s_wrpkt(ssh, pkt);
1491 ssh_free_packet(pkt);
fb09bf1c 1492}
1493
51470298 1494static void defer_packet(Ssh ssh, int pkttype, ...)
32874aea 1495{
ff3187f6 1496 struct Packet *pkt;
39065bed 1497 va_list ap1, ap2;
1498 va_start(ap1, pkttype);
1499 va_start(ap2, pkttype);
ff3187f6 1500 pkt = construct_packet(ssh, pkttype, ap1, ap2);
1501 va_end(ap2);
1502 va_end(ap1);
1503 s_wrpkt_defer(ssh, pkt);
1504 ssh_free_packet(pkt);
39065bed 1505}
1506
32874aea 1507static int ssh_versioncmp(char *a, char *b)
1508{
9697bfd2 1509 char *ae, *be;
1510 unsigned long av, bv;
1511
43aa02a7 1512 av = strtoul(a, &ae, 10);
1513 bv = strtoul(b, &be, 10);
32874aea 1514 if (av != bv)
1515 return (av < bv ? -1 : +1);
1516 if (*ae == '.')
1517 ae++;
1518 if (*be == '.')
1519 be++;
43aa02a7 1520 av = strtoul(ae, &ae, 10);
1521 bv = strtoul(be, &be, 10);
32874aea 1522 if (av != bv)
1523 return (av < bv ? -1 : +1);
9697bfd2 1524 return 0;
1525}
1526
e5574168 1527/*
a92dd380 1528 * Utility routines for putting an SSH-protocol `string' and
1529 * `uint32' into a SHA state.
e5574168 1530 */
1531#include <stdio.h>
32874aea 1532static void sha_string(SHA_State * s, void *str, int len)
1533{
e5574168 1534 unsigned char lenblk[4];
e5574168 1535 PUT_32BIT(lenblk, len);
e5574168 1536 SHA_Bytes(s, lenblk, 4);
e5574168 1537 SHA_Bytes(s, str, len);
1538}
1539
32874aea 1540static void sha_uint32(SHA_State * s, unsigned i)
1541{
a92dd380 1542 unsigned char intblk[4];
1543 PUT_32BIT(intblk, i);
1544 SHA_Bytes(s, intblk, 4);
1545}
1546
7cca0d81 1547/*
1548 * SSH2 packet construction functions.
1549 */
ff3187f6 1550static void ssh2_pkt_ensure(struct Packet *pkt, int length)
32874aea 1551{
ff3187f6 1552 if (pkt->maxlen < length) {
1553 pkt->maxlen = length + 256;
1554 pkt->data = sresize(pkt->data, pkt->maxlen + APIEXTRA, unsigned char);
7cca0d81 1555 }
783415f8 1556}
ff3187f6 1557static void ssh2_pkt_adddata(struct Packet *pkt, void *data, int len)
32874aea 1558{
ff3187f6 1559 if (pkt->logmode != PKTLOG_EMIT) {
1560 pkt->nblanks++;
1561 pkt->blanks = sresize(pkt->blanks, pkt->nblanks, struct logblank_t);
1562 pkt->blanks[pkt->nblanks-1].offset = pkt->length - 6;
1563 pkt->blanks[pkt->nblanks-1].len = len;
1564 pkt->blanks[pkt->nblanks-1].type = pkt->logmode;
1565 }
1566 pkt->length += len;
1567 ssh2_pkt_ensure(pkt, pkt->length);
1568 memcpy(pkt->data + pkt->length - len, data, len);
7cca0d81 1569}
ff3187f6 1570static void ssh2_pkt_addbyte(struct Packet *pkt, unsigned char byte)
32874aea 1571{
ff3187f6 1572 ssh2_pkt_adddata(pkt, &byte, 1);
7cca0d81 1573}
ff3187f6 1574static struct Packet *ssh2_pkt_init(int pkt_type)
32874aea 1575{
ff3187f6 1576 struct Packet *pkt = ssh_new_packet();
1577 pkt->length = 5;
95d2d262 1578 pkt->forcepad = 0;
ff3187f6 1579 ssh2_pkt_addbyte(pkt, (unsigned char) pkt_type);
1580 return pkt;
7cca0d81 1581}
ff3187f6 1582static void ssh2_pkt_addbool(struct Packet *pkt, unsigned char value)
32874aea 1583{
ff3187f6 1584 ssh2_pkt_adddata(pkt, &value, 1);
7cca0d81 1585}
ff3187f6 1586static void ssh2_pkt_adduint32(struct Packet *pkt, unsigned long value)
32874aea 1587{
7cca0d81 1588 unsigned char x[4];
1589 PUT_32BIT(x, value);
ff3187f6 1590 ssh2_pkt_adddata(pkt, x, 4);
7cca0d81 1591}
ff3187f6 1592static void ssh2_pkt_addstring_start(struct Packet *pkt)
32874aea 1593{
ff3187f6 1594 ssh2_pkt_adduint32(pkt, 0);
1595 pkt->savedpos = pkt->length;
7cca0d81 1596}
ff3187f6 1597static void ssh2_pkt_addstring_str(struct Packet *pkt, char *data)
32874aea 1598{
ff3187f6 1599 ssh2_pkt_adddata(pkt, data, strlen(data));
1600 PUT_32BIT(pkt->data + pkt->savedpos - 4, pkt->length - pkt->savedpos);
7cca0d81 1601}
ff3187f6 1602static void ssh2_pkt_addstring_data(struct Packet *pkt, char *data, int len)
32874aea 1603{
ff3187f6 1604 ssh2_pkt_adddata(pkt, data, len);
1605 PUT_32BIT(pkt->data + pkt->savedpos - 4, pkt->length - pkt->savedpos);
7cca0d81 1606}
ff3187f6 1607static void ssh2_pkt_addstring(struct Packet *pkt, char *data)
32874aea 1608{
ff3187f6 1609 ssh2_pkt_addstring_start(pkt);
1610 ssh2_pkt_addstring_str(pkt, data);
7cca0d81 1611}
d8baa528 1612static unsigned char *ssh2_mpint_fmt(Bignum b, int *len)
32874aea 1613{
7cca0d81 1614 unsigned char *p;
32874aea 1615 int i, n = (bignum_bitcount(b) + 7) / 8;
3d88e64d 1616 p = snewn(n + 1, unsigned char);
7cca0d81 1617 if (!p)
32874aea 1618 fatalbox("out of memory");
7cca0d81 1619 p[0] = 0;
3709bfe9 1620 for (i = 1; i <= n; i++)
32874aea 1621 p[i] = bignum_byte(b, n - i);
7cca0d81 1622 i = 0;
32874aea 1623 while (i <= n && p[i] == 0 && (p[i + 1] & 0x80) == 0)
1624 i++;
1625 memmove(p, p + i, n + 1 - i);
1626 *len = n + 1 - i;
7cca0d81 1627 return p;
1628}
ff3187f6 1629static void ssh2_pkt_addmp(struct Packet *pkt, Bignum b)
32874aea 1630{
7cca0d81 1631 unsigned char *p;
1632 int len;
1633 p = ssh2_mpint_fmt(b, &len);
ff3187f6 1634 ssh2_pkt_addstring_start(pkt);
1635 ssh2_pkt_addstring_data(pkt, (char *)p, len);
dcbde236 1636 sfree(p);
7cca0d81 1637}
b185170a 1638
1639/*
1640 * Construct an SSH2 final-form packet: compress it, encrypt it,
1641 * put the MAC on it. Final packet, ready to be sent, is stored in
ff3187f6 1642 * pkt->data. Total length is returned.
b185170a 1643 */
ff3187f6 1644static int ssh2_pkt_construct(Ssh ssh, struct Packet *pkt)
32874aea 1645{
7cca0d81 1646 int cipherblk, maclen, padding, i;
7cca0d81 1647
a8327734 1648 if (ssh->logctx)
ff3187f6 1649 log_packet(ssh->logctx, PKT_OUTGOING, pkt->data[5],
1650 ssh2_pkt_type(ssh->pkt_ctx, pkt->data[5]),
1651 pkt->data + 6, pkt->length - 6,
1652 pkt->nblanks, pkt->blanks);
1653 sfree(pkt->blanks); pkt->blanks = NULL;
1654 pkt->nblanks = 0;
00db133f 1655
7cca0d81 1656 /*
4ba9b64b 1657 * Compress packet payload.
1658 */
4ba9b64b 1659 {
1660 unsigned char *newpayload;
1661 int newlen;
51470298 1662 if (ssh->cscomp &&
ff3187f6 1663 ssh->cscomp->compress(ssh->cs_comp_ctx, pkt->data + 5,
1664 pkt->length - 5,
51470298 1665 &newpayload, &newlen)) {
ff3187f6 1666 pkt->length = 5;
1667 ssh2_pkt_adddata(pkt, newpayload, newlen);
dcbde236 1668 sfree(newpayload);
4ba9b64b 1669 }
1670 }
1671
1672 /*
7cca0d81 1673 * Add padding. At least four bytes, and must also bring total
1674 * length (minus MAC) up to a multiple of the block size.
95d2d262 1675 * If pkt->forcepad is set, make sure the packet is at least that size
1676 * after padding.
7cca0d81 1677 */
51470298 1678 cipherblk = ssh->cscipher ? ssh->cscipher->blksize : 8; /* block size */
32874aea 1679 cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
7cca0d81 1680 padding = 4;
95d2d262 1681 if (pkt->length + padding < pkt->forcepad)
1682 padding = pkt->forcepad - pkt->length;
32874aea 1683 padding +=
ff3187f6 1684 (cipherblk - (pkt->length + padding) % cipherblk) % cipherblk;
95d2d262 1685 assert(padding <= 255);
51470298 1686 maclen = ssh->csmac ? ssh->csmac->len : 0;
ff3187f6 1687 ssh2_pkt_ensure(pkt, pkt->length + padding + maclen);
1688 pkt->data[4] = padding;
7cca0d81 1689 for (i = 0; i < padding; i++)
ff3187f6 1690 pkt->data[pkt->length + i] = random_byte();
1691 PUT_32BIT(pkt->data, pkt->length + padding - 4);
51470298 1692 if (ssh->csmac)
ff3187f6 1693 ssh->csmac->generate(ssh->cs_mac_ctx, pkt->data,
1694 pkt->length + padding,
51470298 1695 ssh->v2_outgoing_sequence);
1696 ssh->v2_outgoing_sequence++; /* whether or not we MACed */
1697
1698 if (ssh->cscipher)
371e569c 1699 ssh->cscipher->encrypt(ssh->cs_cipher_ctx,
ff3187f6 1700 pkt->data, pkt->length + padding);
51470298 1701
9442dd57 1702 pkt->encrypted_len = pkt->length + padding;
1703
ff3187f6 1704 /* Ready-to-send packet starts at pkt->data. We return length. */
1705 return pkt->length + padding + maclen;
b185170a 1706}
1707
1708/*
590f6a5f 1709 * Routines called from the main SSH code to send packets. There
1710 * are quite a few of these, because we have two separate
1711 * mechanisms for delaying the sending of packets:
1712 *
1713 * - In order to send an IGNORE message and a password message in
1714 * a single fixed-length blob, we require the ability to
1715 * concatenate the encrypted forms of those two packets _into_ a
1716 * single blob and then pass it to our <network.h> transport
1717 * layer in one go. Hence, there's a deferment mechanism which
1718 * works after packet encryption.
1719 *
1720 * - In order to avoid sending any connection-layer messages
1721 * during repeat key exchange, we have to queue up any such
1722 * outgoing messages _before_ they are encrypted (and in
1723 * particular before they're allocated sequence numbers), and
1724 * then send them once we've finished.
1725 *
1726 * I call these mechanisms `defer' and `queue' respectively, so as
1727 * to distinguish them reasonably easily.
1728 *
1729 * The functions send_noqueue() and defer_noqueue() free the packet
1730 * structure they are passed. Every outgoing packet goes through
1731 * precisely one of these functions in its life; packets passed to
1732 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1733 * these or get queued, and then when the queue is later emptied
1734 * the packets are all passed to defer_noqueue().
b185170a 1735 */
590f6a5f 1736
1737/*
1738 * Send an SSH2 packet immediately, without queuing or deferring.
1739 */
1740static void ssh2_pkt_send_noqueue(Ssh ssh, struct Packet *pkt)
32874aea 1741{
5471d09a 1742 int len;
1743 int backlog;
ff3187f6 1744 len = ssh2_pkt_construct(ssh, pkt);
1745 backlog = sk_write(ssh->s, (char *)pkt->data, len);
5471d09a 1746 if (backlog > SSH_MAX_BACKLOG)
51470298 1747 ssh_throttle_all(ssh, 1, backlog);
9442dd57 1748
1749 ssh->outgoing_data_size += pkt->encrypted_len;
1750 if (!ssh->kex_in_progress &&
d57f70af 1751 ssh->max_data_size != 0 &&
1752 ssh->outgoing_data_size > ssh->max_data_size)
f382c87d 1753 do_ssh2_transport(ssh, "too much data sent", -1, NULL);
9442dd57 1754
ff3187f6 1755 ssh_free_packet(pkt);
b185170a 1756}
1757
1758/*
590f6a5f 1759 * Defer an SSH2 packet.
b185170a 1760 */
590f6a5f 1761static void ssh2_pkt_defer_noqueue(Ssh ssh, struct Packet *pkt)
32874aea 1762{
ff3187f6 1763 int len = ssh2_pkt_construct(ssh, pkt);
51470298 1764 if (ssh->deferred_len + len > ssh->deferred_size) {
1765 ssh->deferred_size = ssh->deferred_len + len + 128;
3d88e64d 1766 ssh->deferred_send_data = sresize(ssh->deferred_send_data,
1767 ssh->deferred_size,
1768 unsigned char);
b185170a 1769 }
ff3187f6 1770 memcpy(ssh->deferred_send_data + ssh->deferred_len, pkt->data, len);
51470298 1771 ssh->deferred_len += len;
9442dd57 1772 ssh->deferred_data_size += pkt->encrypted_len;
ff3187f6 1773 ssh_free_packet(pkt);
b185170a 1774}
1775
1776/*
590f6a5f 1777 * Queue an SSH2 packet.
1778 */
1779static void ssh2_pkt_queue(Ssh ssh, struct Packet *pkt)
1780{
1781 assert(ssh->queueing);
1782
1783 if (ssh->queuelen >= ssh->queuesize) {
1784 ssh->queuesize = ssh->queuelen + 32;
1785 ssh->queue = sresize(ssh->queue, ssh->queuesize, struct Packet *);
1786 }
1787
1788 ssh->queue[ssh->queuelen++] = pkt;
1789}
1790
1791/*
1792 * Either queue or send a packet, depending on whether queueing is
1793 * set.
1794 */
1795static void ssh2_pkt_send(Ssh ssh, struct Packet *pkt)
1796{
1797 if (ssh->queueing)
1798 ssh2_pkt_queue(ssh, pkt);
1799 else
1800 ssh2_pkt_send_noqueue(ssh, pkt);
1801}
1802
95d2d262 1803#if 0 /* disused */
590f6a5f 1804/*
1805 * Either queue or defer a packet, depending on whether queueing is
1806 * set.
1807 */
1808static void ssh2_pkt_defer(Ssh ssh, struct Packet *pkt)
1809{
1810 if (ssh->queueing)
1811 ssh2_pkt_queue(ssh, pkt);
1812 else
1813 ssh2_pkt_defer_noqueue(ssh, pkt);
1814}
95d2d262 1815#endif
590f6a5f 1816
1817/*
b185170a 1818 * Send the whole deferred data block constructed by
39065bed 1819 * ssh2_pkt_defer() or SSH1's defer_packet().
590f6a5f 1820 *
1821 * The expected use of the defer mechanism is that you call
1822 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1823 * not currently queueing, this simply sets up deferred_send_data
1824 * and then sends it. If we _are_ currently queueing, the calls to
1825 * ssh2_pkt_defer() put the deferred packets on to the queue
1826 * instead, and therefore ssh_pkt_defersend() has no deferred data
1827 * to send. Hence, there's no need to make it conditional on
1828 * ssh->queueing.
b185170a 1829 */
51470298 1830static void ssh_pkt_defersend(Ssh ssh)
32874aea 1831{
5471d09a 1832 int backlog;
d8baa528 1833 backlog = sk_write(ssh->s, (char *)ssh->deferred_send_data,
1834 ssh->deferred_len);
51470298 1835 ssh->deferred_len = ssh->deferred_size = 0;
1836 sfree(ssh->deferred_send_data);
1837 ssh->deferred_send_data = NULL;
5471d09a 1838 if (backlog > SSH_MAX_BACKLOG)
51470298 1839 ssh_throttle_all(ssh, 1, backlog);
9442dd57 1840
1841 ssh->outgoing_data_size += ssh->deferred_data_size;
1842 if (!ssh->kex_in_progress &&
d57f70af 1843 ssh->max_data_size != 0 &&
1844 ssh->outgoing_data_size > ssh->max_data_size)
f382c87d 1845 do_ssh2_transport(ssh, "too much data sent", -1, NULL);
9442dd57 1846 ssh->deferred_data_size = 0;
7cca0d81 1847}
1848
590f6a5f 1849/*
1850 * Send all queued SSH2 packets. We send them by means of
1851 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1852 * packets that needed to be lumped together.
1853 */
1854static void ssh2_pkt_queuesend(Ssh ssh)
1855{
1856 int i;
1857
1858 assert(!ssh->queueing);
1859
1860 for (i = 0; i < ssh->queuelen; i++)
1861 ssh2_pkt_defer_noqueue(ssh, ssh->queue[i]);
1862 ssh->queuelen = 0;
1863
1864 ssh_pkt_defersend(ssh);
1865}
1866
7cca0d81 1867#if 0
32874aea 1868void bndebug(char *string, Bignum b)
1869{
7cca0d81 1870 unsigned char *p;
1871 int i, len;
1872 p = ssh2_mpint_fmt(b, &len);
1873 debug(("%s", string));
1874 for (i = 0; i < len; i++)
32874aea 1875 debug((" %02x", p[i]));
765c4200 1876 debug(("\n"));
dcbde236 1877 sfree(p);
7cca0d81 1878}
1879#endif
1880
32874aea 1881static void sha_mpint(SHA_State * s, Bignum b)
1882{
7cca0d81 1883 unsigned char *p;
1884 int len;
1885 p = ssh2_mpint_fmt(b, &len);
1886 sha_string(s, p, len);
dcbde236 1887 sfree(p);
7cca0d81 1888}
1889
1890/*
0016d70b 1891 * Packet decode functions for both SSH1 and SSH2.
7cca0d81 1892 */
ff3187f6 1893static unsigned long ssh_pkt_getuint32(struct Packet *pkt)
32874aea 1894{
7cca0d81 1895 unsigned long value;
ff3187f6 1896 if (pkt->length - pkt->savedpos < 4)
32874aea 1897 return 0; /* arrgh, no way to decline (FIXME?) */
ff3187f6 1898 value = GET_32BIT(pkt->body + pkt->savedpos);
1899 pkt->savedpos += 4;
7cca0d81 1900 return value;
1901}
ff3187f6 1902static int ssh2_pkt_getbool(struct Packet *pkt)
32874aea 1903{
65a22376 1904 unsigned long value;
ff3187f6 1905 if (pkt->length - pkt->savedpos < 1)
32874aea 1906 return 0; /* arrgh, no way to decline (FIXME?) */
ff3187f6 1907 value = pkt->body[pkt->savedpos] != 0;
1908 pkt->savedpos++;
65a22376 1909 return value;
1910}
ff3187f6 1911static void ssh_pkt_getstring(struct Packet *pkt, char **p, int *length)
32874aea 1912{
57356d63 1913 int len;
7cca0d81 1914 *p = NULL;
45068b27 1915 *length = 0;
ff3187f6 1916 if (pkt->length - pkt->savedpos < 4)
32874aea 1917 return;
ff3187f6 1918 len = GET_32BIT(pkt->body + pkt->savedpos);
57356d63 1919 if (len < 0)
1920 return;
1921 *length = len;
ff3187f6 1922 pkt->savedpos += 4;
1923 if (pkt->length - pkt->savedpos < *length)
32874aea 1924 return;
ff3187f6 1925 *p = (char *)(pkt->body + pkt->savedpos);
1926 pkt->savedpos += *length;
7cca0d81 1927}
ff3187f6 1928static void *ssh_pkt_getdata(struct Packet *pkt, int length)
0016d70b 1929{
ff3187f6 1930 if (pkt->length - pkt->savedpos < length)
0016d70b 1931 return NULL;
ff3187f6 1932 pkt->savedpos += length;
1933 return pkt->body + (pkt->savedpos - length);
0016d70b 1934}
ff3187f6 1935static int ssh1_pkt_getrsakey(struct Packet *pkt, struct RSAKey *key,
0016d70b 1936 unsigned char **keystr)
1937{
1938 int j;
1939
ff3187f6 1940 j = makekey(pkt->body + pkt->savedpos,
1941 pkt->length - pkt->savedpos,
0016d70b 1942 key, keystr, 0);
1943
1944 if (j < 0)
1945 return FALSE;
1946
ff3187f6 1947 pkt->savedpos += j;
1948 assert(pkt->savedpos < pkt->length);
0016d70b 1949
1950 return TRUE;
1951}
ff3187f6 1952static Bignum ssh1_pkt_getmp(struct Packet *pkt)
0016d70b 1953{
1954 int j;
1955 Bignum b;
1956
ff3187f6 1957 j = ssh1_read_bignum(pkt->body + pkt->savedpos,
1958 pkt->length - pkt->savedpos, &b);
0016d70b 1959
1960 if (j < 0)
1961 return NULL;
1962
ff3187f6 1963 pkt->savedpos += j;
0016d70b 1964 return b;
1965}
ff3187f6 1966static Bignum ssh2_pkt_getmp(struct Packet *pkt)
32874aea 1967{
7cca0d81 1968 char *p;
3709bfe9 1969 int length;
7cca0d81 1970 Bignum b;
1971
ff3187f6 1972 ssh_pkt_getstring(pkt, &p, &length);
7cca0d81 1973 if (!p)
32874aea 1974 return NULL;
ff3187f6 1975 if (p[0] & 0x80)
32874aea 1976 return NULL;
d8baa528 1977 b = bignum_from_bytes((unsigned char *)p, length);
7cca0d81 1978 return b;
1979}
1980
7d503c31 1981/*
1dd353b5 1982 * Helper function to add an SSH2 signature blob to a packet.
1983 * Expects to be shown the public key blob as well as the signature
1984 * blob. Normally works just like ssh2_pkt_addstring, but will
1985 * fiddle with the signature packet if necessary for
1986 * BUG_SSH2_RSA_PADDING.
1987 */
ff3187f6 1988static void ssh2_add_sigblob(Ssh ssh, struct Packet *pkt,
1989 void *pkblob_v, int pkblob_len,
1dd353b5 1990 void *sigblob_v, int sigblob_len)
1991{
1992 unsigned char *pkblob = (unsigned char *)pkblob_v;
1993 unsigned char *sigblob = (unsigned char *)sigblob_v;
1994
1995 /* dmemdump(pkblob, pkblob_len); */
1996 /* dmemdump(sigblob, sigblob_len); */
1997
1998 /*
1999 * See if this is in fact an ssh-rsa signature and a buggy
2000 * server; otherwise we can just do this the easy way.
2001 */
51470298 2002 if ((ssh->remote_bugs & BUG_SSH2_RSA_PADDING) &&
1dd353b5 2003 (GET_32BIT(pkblob) == 7 && !memcmp(pkblob+4, "ssh-rsa", 7))) {
2004 int pos, len, siglen;
2005
2006 /*
2007 * Find the byte length of the modulus.
2008 */
2009
2010 pos = 4+7; /* skip over "ssh-rsa" */
2011 pos += 4 + GET_32BIT(pkblob+pos); /* skip over exponent */
2012 len = GET_32BIT(pkblob+pos); /* find length of modulus */
2013 pos += 4; /* find modulus itself */
2014 while (len > 0 && pkblob[pos] == 0)
2015 len--, pos++;
2016 /* debug(("modulus length is %d\n", len)); */
2017
2018 /*
2019 * Now find the signature integer.
2020 */
2021 pos = 4+7; /* skip over "ssh-rsa" */
2022 siglen = GET_32BIT(sigblob+pos);
2023 /* debug(("signature length is %d\n", siglen)); */
2024
2025 if (len != siglen) {
2026 unsigned char newlen[4];
ff3187f6 2027 ssh2_pkt_addstring_start(pkt);
2028 ssh2_pkt_addstring_data(pkt, (char *)sigblob, pos);
1dd353b5 2029 /* dmemdump(sigblob, pos); */
2030 pos += 4; /* point to start of actual sig */
2031 PUT_32BIT(newlen, len);
ff3187f6 2032 ssh2_pkt_addstring_data(pkt, (char *)newlen, 4);
1dd353b5 2033 /* dmemdump(newlen, 4); */
2034 newlen[0] = 0;
2035 while (len-- > siglen) {
ff3187f6 2036 ssh2_pkt_addstring_data(pkt, (char *)newlen, 1);
1dd353b5 2037 /* dmemdump(newlen, 1); */
2038 }
ff3187f6 2039 ssh2_pkt_addstring_data(pkt, (char *)(sigblob+pos), siglen);
1dd353b5 2040 /* dmemdump(sigblob+pos, siglen); */
2041 return;
2042 }
2043
2044 /* Otherwise fall through and do it the easy way. */
2045 }
2046
ff3187f6 2047 ssh2_pkt_addstring_start(pkt);
2048 ssh2_pkt_addstring_data(pkt, (char *)sigblob, sigblob_len);
1dd353b5 2049}
2050
2051/*
7d503c31 2052 * Examine the remote side's version string and compare it against
2053 * a list of known buggy implementations.
2054 */
51470298 2055static void ssh_detect_bugs(Ssh ssh, char *vstring)
32874aea 2056{
2057 char *imp; /* pointer to implementation part */
7d503c31 2058 imp = vstring;
2059 imp += strcspn(imp, "-");
bd358db1 2060 if (*imp) imp++;
7d503c31 2061 imp += strcspn(imp, "-");
bd358db1 2062 if (*imp) imp++;
7d503c31 2063
51470298 2064 ssh->remote_bugs = 0;
7d503c31 2065
5ecd7ad0 2066 if (ssh->cfg.sshbug_ignore1 == FORCE_ON ||
2067 (ssh->cfg.sshbug_ignore1 == AUTO &&
2c9c6388 2068 (!strcmp(imp, "1.2.18") || !strcmp(imp, "1.2.19") ||
2069 !strcmp(imp, "1.2.20") || !strcmp(imp, "1.2.21") ||
46ac09aa 2070 !strcmp(imp, "1.2.22") || !strcmp(imp, "Cisco-1.25") ||
bd0b4caf 2071 !strcmp(imp, "OSU_1.4alpha3") || !strcmp(imp, "OSU_1.5alpha4")))) {
32874aea 2072 /*
2073 * These versions don't support SSH1_MSG_IGNORE, so we have
2074 * to use a different defence against password length
2075 * sniffing.
2076 */
51470298 2077 ssh->remote_bugs |= BUG_CHOKES_ON_SSH1_IGNORE;
32874aea 2078 logevent("We believe remote version has SSH1 ignore bug");
7d503c31 2079 }
2080
5ecd7ad0 2081 if (ssh->cfg.sshbug_plainpw1 == FORCE_ON ||
2082 (ssh->cfg.sshbug_plainpw1 == AUTO &&
46ac09aa 2083 (!strcmp(imp, "Cisco-1.25") || !strcmp(imp, "OSU_1.4alpha3")))) {
bd358db1 2084 /*
2085 * These versions need a plain password sent; they can't
2086 * handle having a null and a random length of data after
2087 * the password.
2088 */
51470298 2089 ssh->remote_bugs |= BUG_NEEDS_SSH1_PLAIN_PASSWORD;
bd358db1 2090 logevent("We believe remote version needs a plain SSH1 password");
2091 }
2092
5ecd7ad0 2093 if (ssh->cfg.sshbug_rsa1 == FORCE_ON ||
2094 (ssh->cfg.sshbug_rsa1 == AUTO &&
2c9c6388 2095 (!strcmp(imp, "Cisco-1.25")))) {
0df73905 2096 /*
2097 * These versions apparently have no clue whatever about
2098 * RSA authentication and will panic and die if they see
2099 * an AUTH_RSA message.
2100 */
51470298 2101 ssh->remote_bugs |= BUG_CHOKES_ON_RSA;
0df73905 2102 logevent("We believe remote version can't handle RSA authentication");
2103 }
2104
5ecd7ad0 2105 if (ssh->cfg.sshbug_hmac2 == FORCE_ON ||
2106 (ssh->cfg.sshbug_hmac2 == AUTO &&
b9f387af 2107 !wc_match("* VShell", imp) &&
831301f6 2108 (wc_match("2.1.0*", imp) || wc_match("2.0.*", imp) ||
2109 wc_match("2.2.0*", imp) || wc_match("2.3.0*", imp) ||
2110 wc_match("2.1 *", imp)))) {
32874aea 2111 /*
2112 * These versions have the HMAC bug.
2113 */
51470298 2114 ssh->remote_bugs |= BUG_SSH2_HMAC;
32874aea 2115 logevent("We believe remote version has SSH2 HMAC bug");
7d503c31 2116 }
1dd353b5 2117
5ecd7ad0 2118 if (ssh->cfg.sshbug_derivekey2 == FORCE_ON ||
2119 (ssh->cfg.sshbug_derivekey2 == AUTO &&
b9f387af 2120 !wc_match("* VShell", imp) &&
2856a1b9 2121 (wc_match("2.0.0*", imp) || wc_match("2.0.10*", imp) ))) {
088bde77 2122 /*
2123 * These versions have the key-derivation bug (failing to
2124 * include the literal shared secret in the hashes that
2125 * generate the keys).
2126 */
51470298 2127 ssh->remote_bugs |= BUG_SSH2_DERIVEKEY;
088bde77 2128 logevent("We believe remote version has SSH2 key-derivation bug");
2129 }
2130
5ecd7ad0 2131 if (ssh->cfg.sshbug_rsapad2 == FORCE_ON ||
2132 (ssh->cfg.sshbug_rsapad2 == AUTO &&
831301f6 2133 (wc_match("OpenSSH_2.[5-9]*", imp) ||
2134 wc_match("OpenSSH_3.[0-2]*", imp)))) {
1dd353b5 2135 /*
2136 * These versions have the SSH2 RSA padding bug.
2137 */
51470298 2138 ssh->remote_bugs |= BUG_SSH2_RSA_PADDING;
1dd353b5 2139 logevent("We believe remote version has SSH2 RSA padding bug");
2140 }
8e975795 2141
dda87a28 2142 if (ssh->cfg.sshbug_pksessid2 == FORCE_ON ||
2143 (ssh->cfg.sshbug_pksessid2 == AUTO &&
2144 wc_match("OpenSSH_2.[0-2]*", imp))) {
2145 /*
2146 * These versions have the SSH2 session-ID bug in
2147 * public-key authentication.
2148 */
2149 ssh->remote_bugs |= BUG_SSH2_PK_SESSIONID;
2150 logevent("We believe remote version has SSH2 public-key-session-ID bug");
2151 }
f382c87d 2152
2153 if (ssh->cfg.sshbug_rekey2 == FORCE_ON ||
2154 (ssh->cfg.sshbug_rekey2 == AUTO &&
e12d95a5 2155 (wc_match("OpenSSH_2.[0-4]*", imp) ||
2156 wc_match("OpenSSH_2.5.[0-3]*", imp) ||
2157 wc_match("Sun_SSH_1.0", imp) ||
7cb41bb2 2158 wc_match("Sun_SSH_1.0.1", imp)))) {
f382c87d 2159 /*
e12d95a5 2160 * These versions have the SSH2 rekey bug.
f382c87d 2161 */
2162 ssh->remote_bugs |= BUG_SSH2_REKEY;
e12d95a5 2163 logevent("We believe remote version has SSH2 rekey bug");
f382c87d 2164 }
7d503c31 2165}
2166
d38d6a1f 2167/*
2168 * The `software version' part of an SSH version string is required
2169 * to contain no spaces or minus signs.
2170 */
2171static void ssh_fix_verstring(char *str)
2172{
2173 /* Eat "SSH-<protoversion>-". */
2174 assert(*str == 'S'); str++;
2175 assert(*str == 'S'); str++;
2176 assert(*str == 'H'); str++;
2177 assert(*str == '-'); str++;
2178 while (*str && *str != '-') str++;
2179 assert(*str == '-'); str++;
2180
2181 /* Convert minus signs and spaces in the remaining string into
2182 * underscores. */
2183 while (*str) {
2184 if (*str == '-' || *str == ' ')
2185 *str = '_';
2186 str++;
2187 }
2188}
2189
51470298 2190static int do_ssh_init(Ssh ssh, unsigned char c)
32874aea 2191{
51470298 2192 struct do_ssh_init_state {
2193 int vslen;
2194 char version[10];
2195 char *vstring;
2196 int vstrsize;
2197 int i;
2198 int proto1, proto2;
2199 };
2200 crState(do_ssh_init_state);
374330e2 2201
51470298 2202 crBegin(ssh->do_ssh_init_crstate);
8df7a775 2203
2204 /* Search for the string "SSH-" in the input. */
51470298 2205 s->i = 0;
8df7a775 2206 while (1) {
2207 static const int transS[] = { 1, 2, 2, 1 };
2208 static const int transH[] = { 0, 0, 3, 0 };
2209 static const int transminus[] = { 0, 0, 0, -1 };
32874aea 2210 if (c == 'S')
51470298 2211 s->i = transS[s->i];
32874aea 2212 else if (c == 'H')
51470298 2213 s->i = transH[s->i];
32874aea 2214 else if (c == '-')
51470298 2215 s->i = transminus[s->i];
32874aea 2216 else
51470298 2217 s->i = 0;
2218 if (s->i < 0)
8df7a775 2219 break;
2220 crReturn(1); /* get another character */
374330e2 2221 }
8df7a775 2222
51470298 2223 s->vstrsize = 16;
3d88e64d 2224 s->vstring = snewn(s->vstrsize, char);
51470298 2225 strcpy(s->vstring, "SSH-");
2226 s->vslen = 4;
2227 s->i = 0;
374330e2 2228 while (1) {
8df7a775 2229 crReturn(1); /* get another char */
51470298 2230 if (s->vslen >= s->vstrsize - 1) {
2231 s->vstrsize += 16;
3d88e64d 2232 s->vstring = sresize(s->vstring, s->vstrsize, char);
32874aea 2233 }
51470298 2234 s->vstring[s->vslen++] = c;
2235 if (s->i >= 0) {
374330e2 2236 if (c == '-') {
51470298 2237 s->version[s->i] = '\0';
2238 s->i = -1;
2239 } else if (s->i < sizeof(s->version) - 1)
2240 s->version[s->i++] = c;
c4ffc4d0 2241 } else if (c == '\012')
374330e2 2242 break;
2243 }
2244
51470298 2245 ssh->agentfwd_enabled = FALSE;
2246 ssh->rdpkt2_state.incoming_sequence = 0;
960e736a 2247
51470298 2248 s->vstring[s->vslen] = 0;
a7d4653a 2249 s->vstring[strcspn(s->vstring, "\015\012")] = '\0';/* remove EOL chars */
fb983202 2250 logeventf(ssh, "Server version: %s", s->vstring);
51470298 2251 ssh_detect_bugs(ssh, s->vstring);
c5e9c988 2252
adf799dd 2253 /*
38d228a2 2254 * Decide which SSH protocol version to support.
adf799dd 2255 */
38d228a2 2256
2257 /* Anything strictly below "2.0" means protocol 1 is supported. */
51470298 2258 s->proto1 = ssh_versioncmp(s->version, "2.0") < 0;
38d228a2 2259 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
51470298 2260 s->proto2 = ssh_versioncmp(s->version, "1.99") >= 0;
38d228a2 2261
86916870 2262 if (ssh->cfg.sshprot == 0 && !s->proto1) {
6b5cf8b4 2263 bombout(("SSH protocol version 1 required by user but not provided by server"));
7ffdbc1a 2264 crStop(0);
38d228a2 2265 }
86916870 2266 if (ssh->cfg.sshprot == 3 && !s->proto2) {
6b5cf8b4 2267 bombout(("SSH protocol version 2 required by user but not provided by server"));
7ffdbc1a 2268 crStop(0);
38d228a2 2269 }
2270
d38d6a1f 2271 {
2272 char *verstring;
2273
2274 if (s->proto2 && (ssh->cfg.sshprot >= 2 || !s->proto1)) {
2275 /*
2276 * Construct a v2 version string.
2277 */
a7d4653a 2278 verstring = dupprintf("SSH-2.0-%s\015\012", sshver);
d38d6a1f 2279 ssh->version = 2;
2280 } else {
2281 /*
2282 * Construct a v1 version string.
2283 */
a7d4653a 2284 verstring = dupprintf("SSH-%s-%s\012",
d38d6a1f 2285 (ssh_versioncmp(s->version, "1.5") <= 0 ?
2286 s->version : "1.5"),
2287 sshver);
2288 ssh->version = 1;
2289 }
2290
2291 ssh_fix_verstring(verstring);
2292
2293 if (ssh->version == 2) {
2294 /*
2295 * Hash our version string and their version string.
2296 */
2297 SHA_Init(&ssh->exhashbase);
0b351b6b 2298 sha_string(&ssh->exhashbase, verstring,
a7d4653a 2299 strcspn(verstring, "\015\012"));
0b351b6b 2300 sha_string(&ssh->exhashbase, s->vstring,
a7d4653a 2301 strcspn(s->vstring, "\015\012"));
d38d6a1f 2302
2303 /*
2304 * Initialise SSHv2 protocol.
2305 */
2306 ssh->protocol = ssh2_protocol;
2307 ssh2_protocol_setup(ssh);
2308 ssh->s_rdpkt = ssh2_rdpkt;
2309 } else {
2310 /*
2311 * Initialise SSHv1 protocol.
2312 */
2313 ssh->protocol = ssh1_protocol;
2314 ssh1_protocol_setup(ssh);
2315 ssh->s_rdpkt = ssh1_rdpkt;
2316 }
2317 logeventf(ssh, "We claim version: %.*s",
a7d4653a 2318 strcspn(verstring, "\015\012"), verstring);
51470298 2319 sk_write(ssh->s, verstring, strlen(verstring));
d38d6a1f 2320 sfree(verstring);
e5574168 2321 }
d38d6a1f 2322
2323 logeventf(ssh, "Using SSH protocol version %d", ssh->version);
2324
125105d1 2325 update_specials_menu(ssh->frontend);
51470298 2326 ssh->state = SSH_STATE_BEFORE_SIZE;
39934deb 2327 ssh->pinger = pinger_new(&ssh->cfg, &ssh_backend, ssh);
8df7a775 2328
51470298 2329 sfree(s->vstring);
50526e47 2330
8df7a775 2331 crFinish(0);
2332}
2333
51470298 2334static void ssh_gotdata(Ssh ssh, unsigned char *data, int datalen)
8df7a775 2335{
51470298 2336 crBegin(ssh->ssh_gotdata_crstate);
8df7a775 2337
2338 /*
2339 * To begin with, feed the characters one by one to the
2340 * protocol initialisation / selection function do_ssh_init().
2341 * When that returns 0, we're done with the initial greeting
2342 * exchange and can move on to packet discipline.
2343 */
2344 while (1) {
51470298 2345 int ret; /* need not be kept across crReturn */
8df7a775 2346 if (datalen == 0)
2347 crReturnV; /* more data please */
51470298 2348 ret = do_ssh_init(ssh, *data);
32874aea 2349 data++;
2350 datalen--;
8df7a775 2351 if (ret == 0)
2352 break;
2353 }
2354
2355 /*
2356 * We emerge from that loop when the initial negotiation is
2357 * over and we have selected an s_rdpkt function. Now pass
2358 * everything to s_rdpkt, and then pass the resulting packets
2359 * to the proper protocol handler.
2360 */
2361 if (datalen == 0)
2362 crReturnV;
2363 while (1) {
2364 while (datalen > 0) {
ff3187f6 2365 struct Packet *pktin = ssh->s_rdpkt(ssh, &data, &datalen);
2366 if (pktin) {
2367 ssh->protocol(ssh, NULL, 0, pktin);
2368 ssh_free_packet(pktin);
8df7a775 2369 }
ff3187f6 2370 if (ssh->state == SSH_STATE_CLOSED)
2371 return;
8df7a775 2372 }
2373 crReturnV;
2374 }
2375 crFinishV;
2376}
2377
ac934965 2378static int ssh_do_close(Ssh ssh, int notify_exit)
32874aea 2379{
ac934965 2380 int i, ret = 0;
36f94d1f 2381 struct ssh_channel *c;
2382
51470298 2383 ssh->state = SSH_STATE_CLOSED;
2384 if (ssh->s) {
2385 sk_close(ssh->s);
2386 ssh->s = NULL;
ac934965 2387 if (notify_exit)
2388 notify_remote_exit(ssh->frontend);
2389 else
2390 ret = 1;
f3ab576e 2391 }
36f94d1f 2392 /*
2393 * Now we must shut down any port and X forwardings going
2394 * through this connection.
2395 */
74a98066 2396 if (ssh->channels) {
2397 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
2398 switch (c->type) {
2399 case CHAN_X11:
2400 x11_close(c->u.x11.s);
2401 break;
2402 case CHAN_SOCKDATA:
2403 pfd_close(c->u.pfd.s);
2404 break;
2405 }
2406 del234(ssh->channels, c);
2407 if (ssh->version == 2)
2408 bufchain_clear(&c->v.v2.outbuffer);
2409 sfree(c);
36f94d1f 2410 }
36f94d1f 2411 }
ac934965 2412
2413 return ret;
36f94d1f 2414}
2415
7555d6a5 2416static void ssh_log(Plug plug, int type, SockAddr addr, int port,
2417 const char *error_msg, int error_code)
2418{
2419 Ssh ssh = (Ssh) plug;
2420 char addrbuf[256], *msg;
2421
2422 sk_getaddr(addr, addrbuf, lenof(addrbuf));
2423
2424 if (type == 0)
2425 msg = dupprintf("Connecting to %s port %d", addrbuf, port);
2426 else
2427 msg = dupprintf("Failed to connect to %s: %s", addrbuf, error_msg);
2428
2429 logevent(msg);
fb983202 2430 sfree(msg);
7555d6a5 2431}
2432
cbe2d68f 2433static int ssh_closing(Plug plug, const char *error_msg, int error_code,
36f94d1f 2434 int calling_back)
2435{
2436 Ssh ssh = (Ssh) plug;
ac934965 2437 int need_notify = ssh_do_close(ssh, FALSE);
2438
2439 if (!error_msg && !ssh->close_expected) {
2440 error_msg = "Server unexpectedly closed network connection";
2441 }
2442
7e78000d 2443 if (error_msg) {
32874aea 2444 /* A socket error has occurred. */
247308b5 2445 logevent(error_msg);
971bcc0a 2446 connection_fatal(ssh->frontend, "%s", error_msg);
7e78000d 2447 } else {
ac934965 2448 logevent("Server closed network connection");
8df7a775 2449 }
ac934965 2450 if (need_notify)
2451 notify_remote_exit(ssh->frontend);
7e78000d 2452 return 0;
2453}
2454
32874aea 2455static int ssh_receive(Plug plug, int urgent, char *data, int len)
2456{
51470298 2457 Ssh ssh = (Ssh) plug;
d8baa528 2458 ssh_gotdata(ssh, (unsigned char *)data, len);
51470298 2459 if (ssh->state == SSH_STATE_CLOSED) {
ac934965 2460 ssh_do_close(ssh, TRUE);
32874aea 2461 return 0;
3257deae 2462 }
fef97f43 2463 return 1;
374330e2 2464}
2465
5471d09a 2466static void ssh_sent(Plug plug, int bufsize)
2467{
51470298 2468 Ssh ssh = (Ssh) plug;
5471d09a 2469 /*
2470 * If the send backlog on the SSH socket itself clears, we
2471 * should unthrottle the whole world if it was throttled.
2472 */
2473 if (bufsize < SSH_MAX_BACKLOG)
51470298 2474 ssh_throttle_all(ssh, 0, bufsize);
5471d09a 2475}
2476
fb09bf1c 2477/*
8df7a775 2478 * Connect to specified host and port.
2479 * Returns an error message, or NULL on success.
6e1ebb76 2480 * Also places the canonical host name into `realhost'. It must be
2481 * freed by the caller.
8df7a775 2482 */
cbe2d68f 2483static const char *connect_to_host(Ssh ssh, char *host, int port,
79bf227b 2484 char **realhost, int nodelay, int keepalive)
8df7a775 2485{
51470298 2486 static const struct plug_function_table fn_table = {
7555d6a5 2487 ssh_log,
7e78000d 2488 ssh_closing,
5471d09a 2489 ssh_receive,
2490 ssh_sent,
2491 NULL
51470298 2492 };
7e78000d 2493
8df7a775 2494 SockAddr addr;
cbe2d68f 2495 const char *err;
8df7a775 2496
3d88e64d 2497 ssh->savedhost = snewn(1 + strlen(host), char);
51470298 2498 if (!ssh->savedhost)
8df7a775 2499 fatalbox("Out of memory");
51470298 2500 strcpy(ssh->savedhost, host);
8df7a775 2501
2502 if (port < 0)
2503 port = 22; /* default ssh port */
51470298 2504 ssh->savedport = port;
8df7a775 2505
2506 /*
2507 * Try to find host.
2508 */
05581745 2509 logeventf(ssh, "Looking up host \"%s\"%s", host,
2510 (ssh->cfg.addressfamily == ADDRTYPE_IPV4 ? " (IPv4)" :
2511 (ssh->cfg.addressfamily == ADDRTYPE_IPV6 ? " (IPv6)" : "")));
2512 addr = name_lookup(host, port, realhost, &ssh->cfg,
2513 ssh->cfg.addressfamily);
170c1e6e 2514 if ((err = sk_addr_error(addr)) != NULL) {
2515 sk_addr_free(addr);
8df7a775 2516 return err;
170c1e6e 2517 }
8df7a775 2518
8df7a775 2519 /*
2520 * Open socket.
2521 */
51470298 2522 ssh->fn = &fn_table;
e8fa8f62 2523 ssh->s = new_connection(addr, *realhost, port,
79bf227b 2524 0, 1, nodelay, keepalive, (Plug) ssh, &ssh->cfg);
70e5d0fd 2525 if ((err = sk_socket_error(ssh->s)) != NULL) {
51470298 2526 ssh->s = NULL;
39934deb 2527 notify_remote_exit(ssh->frontend);
8df7a775 2528 return err;
67c4ba2e 2529 }
8df7a775 2530
8df7a775 2531 return NULL;
2532}
2533
2534/*
5471d09a 2535 * Throttle or unthrottle the SSH connection.
2536 */
51470298 2537static void ssh1_throttle(Ssh ssh, int adjust)
5471d09a 2538{
51470298 2539 int old_count = ssh->v1_throttle_count;
2540 ssh->v1_throttle_count += adjust;
2541 assert(ssh->v1_throttle_count >= 0);
2542 if (ssh->v1_throttle_count && !old_count) {
2543 sk_set_frozen(ssh->s, 1);
2544 } else if (!ssh->v1_throttle_count && old_count) {
2545 sk_set_frozen(ssh->s, 0);
5471d09a 2546 }
2547}
2548
2549/*
2550 * Throttle or unthrottle _all_ local data streams (for when sends
2551 * on the SSH connection itself back up).
2552 */
51470298 2553static void ssh_throttle_all(Ssh ssh, int enable, int bufsize)
5471d09a 2554{
2555 int i;
2556 struct ssh_channel *c;
2557
51470298 2558 if (enable == ssh->throttled_all)
5471d09a 2559 return;
51470298 2560 ssh->throttled_all = enable;
2561 ssh->overall_bufsize = bufsize;
2562 if (!ssh->channels)
5471d09a 2563 return;
51470298 2564 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
5471d09a 2565 switch (c->type) {
2566 case CHAN_MAINSESSION:
2567 /*
2568 * This is treated separately, outside the switch.
2569 */
2570 break;
2571 case CHAN_X11:
2572 x11_override_throttle(c->u.x11.s, enable);
2573 break;
2574 case CHAN_AGENT:
2575 /* Agent channels require no buffer management. */
2576 break;
2577 case CHAN_SOCKDATA:
36f94d1f 2578 pfd_override_throttle(c->u.pfd.s, enable);
5471d09a 2579 break;
2580 }
2581 }
2582}
2583
2584/*
51470298 2585 * Username and password input, abstracted off into routines
2586 * reusable in several places - even between SSH1 and SSH2.
0405e71f 2587 */
0405e71f 2588
2589/* Set up a username or password input loop on a given buffer. */
ae9ae89f 2590static void setup_userpass_input(Ssh ssh, char *buffer, int buflen, int echo)
0405e71f 2591{
51470298 2592 ssh->userpass_input_buffer = buffer;
2593 ssh->userpass_input_buflen = buflen;
2594 ssh->userpass_input_bufpos = 0;
2595 ssh->userpass_input_echo = echo;
0405e71f 2596}
2597
2598/*
2599 * Process some terminal data in the course of username/password
2600 * input. Returns >0 for success (line of input returned in
2601 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2602 * for inconclusive (keep waiting for more input please).
2603 */
ae9ae89f 2604static int process_userpass_input(Ssh ssh, unsigned char *in, int inlen)
0405e71f 2605{
2606 char c;
2607
2608 while (inlen--) {
2609 switch (c = *in++) {
2610 case 10:
2611 case 13:
51470298 2612 ssh->userpass_input_buffer[ssh->userpass_input_bufpos] = 0;
2613 ssh->userpass_input_buffer[ssh->userpass_input_buflen-1] = 0;
0405e71f 2614 return +1;
2615 break;
2616 case 8:
2617 case 127:
51470298 2618 if (ssh->userpass_input_bufpos > 0) {
2619 if (ssh->userpass_input_echo)
2620 c_write_str(ssh, "\b \b");
2621 ssh->userpass_input_bufpos--;
0405e71f 2622 }
2623 break;
2624 case 21:
2625 case 27:
51470298 2626 while (ssh->userpass_input_bufpos > 0) {
2627 if (ssh->userpass_input_echo)
2628 c_write_str(ssh, "\b \b");
2629 ssh->userpass_input_bufpos--;
0405e71f 2630 }
2631 break;
2632 case 3:
2633 case 4:
2634 return -1;
2635 break;
2636 default:
4692a14a 2637 /*
2638 * This simplistic check for printability is disabled
2639 * when we're doing password input, because some people
2640 * have control characters in their passwords.o
2641 */
2642 if ((!ssh->userpass_input_echo ||
2643 (c >= ' ' && c <= '~') ||
0405e71f 2644 ((unsigned char) c >= 160))
51470298 2645 && ssh->userpass_input_bufpos < ssh->userpass_input_buflen-1) {
2646 ssh->userpass_input_buffer[ssh->userpass_input_bufpos++] = c;
2647 if (ssh->userpass_input_echo)
2648 c_write(ssh, &c, 1);
0405e71f 2649 }
2650 break;
2651 }
2652 }
2653 return 0;
2654}
2655
f11d78f2 2656static void ssh_agent_callback(void *sshv, void *reply, int replylen)
839f10db 2657{
2658 Ssh ssh = (Ssh) sshv;
2659
2660 ssh->agent_response = reply;
2661 ssh->agent_response_len = replylen;
2662
2663 if (ssh->version == 1)
ff3187f6 2664 do_ssh1_login(ssh, NULL, -1, NULL);
839f10db 2665 else
ff3187f6 2666 do_ssh2_authconn(ssh, NULL, -1, NULL);
839f10db 2667}
2668
f11d78f2 2669static void ssh_agentf_callback(void *cv, void *reply, int replylen)
839f10db 2670{
2671 struct ssh_channel *c = (struct ssh_channel *)cv;
2672 Ssh ssh = c->ssh;
2673 void *sentreply = reply;
2674
2675 if (!sentreply) {
2676 /* Fake SSH_AGENT_FAILURE. */
2677 sentreply = "\0\0\0\1\5";
2678 replylen = 5;
2679 }
2680 if (ssh->version == 2) {
2681 ssh2_add_channel_data(c, sentreply, replylen);
2682 ssh2_try_send(c);
2683 } else {
2684 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
2685 PKT_INT, c->remoteid,
9a10ecf4 2686 PKTT_DATA,
839f10db 2687 PKT_INT, replylen,
2688 PKT_DATA, sentreply, replylen,
9a10ecf4 2689 PKTT_OTHER,
839f10db 2690 PKT_END);
2691 }
2692 if (reply)
2693 sfree(reply);
2694}
2695
0405e71f 2696/*
fb09bf1c 2697 * Handle the key exchange and user authentication phases.
2698 */
ff3187f6 2699static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen,
2700 struct Packet *pktin)
fb09bf1c 2701{
0016d70b 2702 int i, j, ret;
2703 unsigned char cookie[8], *ptr;
374330e2 2704 struct RSAKey servkey, hostkey;
2705 struct MD5Context md5c;
51470298 2706 struct do_ssh1_login_state {
2707 int len;
2708 unsigned char *rsabuf, *keystr1, *keystr2;
2709 unsigned long supported_ciphers_mask, supported_auths_mask;
2710 int tried_publickey, tried_agent;
2711 int tis_auth_refused, ccard_auth_refused;
2712 unsigned char session_id[16];
2713 int cipher_type;
2714 char username[100];
2715 void *publickey_blob;
2716 int publickey_bloblen;
2717 char password[100];
2718 char prompt[200];
2719 int pos;
2720 char c;
2721 int pwpkt_type;
2722 unsigned char request[5], *response, *p;
2723 int responselen;
2724 int keyi, nkeys;
2725 int authed;
2726 struct RSAKey key;
2727 Bignum challenge;
2728 char *commentp;
2729 int commentlen;
2730 };
2731 crState(do_ssh1_login_state);
2732
2733 crBegin(ssh->do_ssh1_login_crstate);
374330e2 2734
ff3187f6 2735 if (!pktin)
2736 crWaitUntil(pktin);
374330e2 2737
ff3187f6 2738 if (pktin->type != SSH1_SMSG_PUBLIC_KEY) {
6b5cf8b4 2739 bombout(("Public key packet not received"));
7ffdbc1a 2740 crStop(0);
8d5de777 2741 }
374330e2 2742
c5e9c988 2743 logevent("Received public keys");
374330e2 2744
ff3187f6 2745 ptr = ssh_pkt_getdata(pktin, 8);
0016d70b 2746 if (!ptr) {
2747 bombout(("SSH1 public key packet stopped before random cookie"));
2748 crStop(0);
2749 }
2750 memcpy(cookie, ptr, 8);
374330e2 2751
ff3187f6 2752 if (!ssh1_pkt_getrsakey(pktin, &servkey, &s->keystr1) ||
2753 !ssh1_pkt_getrsakey(pktin, &hostkey, &s->keystr2)) {
ae0500e5 2754 bombout(("Failed to read SSH1 public keys from public key packet"));
0016d70b 2755 crStop(0);
2756 }
374330e2 2757
c5e9c988 2758 /*
1c2a93c4 2759 * Log the host key fingerprint.
c5e9c988 2760 */
c5e9c988 2761 {
2762 char logmsg[80];
1c2a93c4 2763 logevent("Host key fingerprint is:");
c5e9c988 2764 strcpy(logmsg, " ");
32874aea 2765 hostkey.comment = NULL;
2766 rsa_fingerprint(logmsg + strlen(logmsg),
2767 sizeof(logmsg) - strlen(logmsg), &hostkey);
c5e9c988 2768 logevent(logmsg);
2769 }
2770
ff3187f6 2771 ssh->v1_remote_protoflags = ssh_pkt_getuint32(pktin);
2772 s->supported_ciphers_mask = ssh_pkt_getuint32(pktin);
2773 s->supported_auths_mask = ssh_pkt_getuint32(pktin);
bea1ef5f 2774
51470298 2775 ssh->v1_local_protoflags =
2776 ssh->v1_remote_protoflags & SSH1_PROTOFLAGS_SUPPORTED;
2777 ssh->v1_local_protoflags |= SSH1_PROTOFLAG_SCREEN_NUMBER;
b96dc54c 2778
c5e9c988 2779 MD5Init(&md5c);
51470298 2780 MD5Update(&md5c, s->keystr2, hostkey.bytes);
2781 MD5Update(&md5c, s->keystr1, servkey.bytes);
0016d70b 2782 MD5Update(&md5c, cookie, 8);
51470298 2783 MD5Final(s->session_id, &md5c);
374330e2 2784
32874aea 2785 for (i = 0; i < 32; i++)
51470298 2786 ssh->session_key[i] = random_byte();
374330e2 2787
0016d70b 2788 /*
2789 * Verify that the `bits' and `bytes' parameters match.
2790 */
2791 if (hostkey.bits > hostkey.bytes * 8 ||
2792 servkey.bits > servkey.bytes * 8) {
2793 bombout(("SSH1 public keys were badly formatted"));
2794 crStop(0);
2795 }
2796
51470298 2797 s->len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
374330e2 2798
3d88e64d 2799 s->rsabuf = snewn(s->len, unsigned char);
51470298 2800 if (!s->rsabuf)
374330e2 2801 fatalbox("Out of memory");
2802
89ee5268 2803 /*
2804 * Verify the host key.
2805 */
2806 {
32874aea 2807 /*
2808 * First format the key into a string.
2809 */
2810 int len = rsastr_len(&hostkey);
2811 char fingerprint[100];
3d88e64d 2812 char *keystr = snewn(len, char);
32874aea 2813 if (!keystr)
2814 fatalbox("Out of memory");
2815 rsastr_fmt(keystr, &hostkey);
2816 rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
a8327734 2817 verify_ssh_host_key(ssh->frontend,
2818 ssh->savedhost, ssh->savedport, "rsa", keystr,
32874aea 2819 fingerprint);
2820 sfree(keystr);
2821 }
2822
2823 for (i = 0; i < 32; i++) {
51470298 2824 s->rsabuf[i] = ssh->session_key[i];
374330e2 2825 if (i < 16)
51470298 2826 s->rsabuf[i] ^= s->session_id[i];
374330e2 2827 }
2828
2829 if (hostkey.bytes > servkey.bytes) {
0016d70b 2830 ret = rsaencrypt(s->rsabuf, 32, &servkey);
2831 if (ret)
2832 ret = rsaencrypt(s->rsabuf, servkey.bytes, &hostkey);
374330e2 2833 } else {
0016d70b 2834 ret = rsaencrypt(s->rsabuf, 32, &hostkey);
2835 if (ret)
2836 ret = rsaencrypt(s->rsabuf, hostkey.bytes, &servkey);
2837 }
2838 if (!ret) {
2839 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2840 crStop(0);
374330e2 2841 }
2842
c5e9c988 2843 logevent("Encrypted session key");
2844
ca20bfcf 2845 {
2846 int cipher_chosen = 0, warn = 0;
2847 char *cipher_string = NULL;
51470298 2848 int i;
ca20bfcf 2849 for (i = 0; !cipher_chosen && i < CIPHER_MAX; i++) {
86916870 2850 int next_cipher = ssh->cfg.ssh_cipherlist[i];
ca20bfcf 2851 if (next_cipher == CIPHER_WARN) {
2852 /* If/when we choose a cipher, warn about it */
2853 warn = 1;
2854 } else if (next_cipher == CIPHER_AES) {
2855 /* XXX Probably don't need to mention this. */
2856 logevent("AES not supported in SSH1, skipping");
2857 } else {
2858 switch (next_cipher) {
51470298 2859 case CIPHER_3DES: s->cipher_type = SSH_CIPHER_3DES;
ca20bfcf 2860 cipher_string = "3DES"; break;
51470298 2861 case CIPHER_BLOWFISH: s->cipher_type = SSH_CIPHER_BLOWFISH;
ca20bfcf 2862 cipher_string = "Blowfish"; break;
51470298 2863 case CIPHER_DES: s->cipher_type = SSH_CIPHER_DES;
ca20bfcf 2864 cipher_string = "single-DES"; break;
2865 }
51470298 2866 if (s->supported_ciphers_mask & (1 << s->cipher_type))
ca20bfcf 2867 cipher_chosen = 1;
2868 }
2869 }
2870 if (!cipher_chosen) {
51470298 2871 if ((s->supported_ciphers_mask & (1 << SSH_CIPHER_3DES)) == 0)
6b5cf8b4 2872 bombout(("Server violates SSH 1 protocol by not "
ca20bfcf 2873 "supporting 3DES encryption"));
2874 else
2875 /* shouldn't happen */
6b5cf8b4 2876 bombout(("No supported ciphers found"));
7ffdbc1a 2877 crStop(0);
a99a05c0 2878 }
ca20bfcf 2879
2880 /* Warn about chosen cipher if necessary. */
bb348ab1 2881 if (warn) {
2882 sk_set_frozen(ssh->s, 1);
83e7d008 2883 askalg(ssh->frontend, "cipher", cipher_string);
bb348ab1 2884 sk_set_frozen(ssh->s, 0);
2885 }
bea1ef5f 2886 }
ca20bfcf 2887
51470298 2888 switch (s->cipher_type) {
32874aea 2889 case SSH_CIPHER_3DES:
2890 logevent("Using 3DES encryption");
2891 break;
2892 case SSH_CIPHER_DES:
2893 logevent("Using single-DES encryption");
2894 break;
2895 case SSH_CIPHER_BLOWFISH:
2896 logevent("Using Blowfish encryption");
2897 break;
c5e9c988 2898 }
bea1ef5f 2899
51470298 2900 send_packet(ssh, SSH1_CMSG_SESSION_KEY,
2901 PKT_CHAR, s->cipher_type,
32874aea 2902 PKT_DATA, cookie, 8,
51470298 2903 PKT_CHAR, (s->len * 8) >> 8, PKT_CHAR, (s->len * 8) & 0xFF,
2904 PKT_DATA, s->rsabuf, s->len,
2905 PKT_INT, ssh->v1_local_protoflags, PKT_END);
fb09bf1c 2906
c5e9c988 2907 logevent("Trying to enable encryption...");
374330e2 2908
51470298 2909 sfree(s->rsabuf);
374330e2 2910
51470298 2911 ssh->cipher = (s->cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
2912 s->cipher_type == SSH_CIPHER_DES ? &ssh_des :
2913 &ssh_3des);
371e569c 2914 ssh->v1_cipher_ctx = ssh->cipher->make_context();
2915 ssh->cipher->sesskey(ssh->v1_cipher_ctx, ssh->session_key);
57356d63 2916 logeventf(ssh, "Initialised %s encryption", ssh->cipher->text_name);
374330e2 2917
0183b242 2918 ssh->crcda_ctx = crcda_make_context();
2919 logevent("Installing CRC compensation attack detector");
2920
679539d7 2921 if (servkey.modulus) {
2922 sfree(servkey.modulus);
2923 servkey.modulus = NULL;
2924 }
2925 if (servkey.exponent) {
2926 sfree(servkey.exponent);
2927 servkey.exponent = NULL;
2928 }
2929 if (hostkey.modulus) {
2930 sfree(hostkey.modulus);
2931 hostkey.modulus = NULL;
2932 }
2933 if (hostkey.exponent) {
2934 sfree(hostkey.exponent);
2935 hostkey.exponent = NULL;
2936 }
ff3187f6 2937 crWaitUntil(pktin);
374330e2 2938
ff3187f6 2939 if (pktin->type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 2940 bombout(("Encryption not successfully enabled"));
7ffdbc1a 2941 crStop(0);
8d5de777 2942 }
374330e2 2943
c5e9c988 2944 logevent("Successfully started encryption");
2945
374330e2 2946 fflush(stdout);
2947 {
aa09f7d0 2948 if (!*ssh->cfg.username) {
c0a81592 2949 if (ssh_get_line && !ssh_getline_pw_only) {
32874aea 2950 if (!ssh_get_line("login as: ",
51470298 2951 s->username, sizeof(s->username), FALSE)) {
32874aea 2952 /*
2953 * get_line failed to get a username.
2954 * Terminate.
2955 */
2956 logevent("No username provided. Abandoning session.");
ac934965 2957 ssh->close_expected = TRUE;
3bb2f322 2958 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 2959 crStop(1);
32874aea 2960 }
2961 } else {
51470298 2962 int ret; /* need not be kept over crReturn */
2963 c_write_str(ssh, "login as: ");
2964 ssh->send_ok = 1;
0405e71f 2965
51470298 2966 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
0405e71f 2967 do {
ff3187f6 2968 crWaitUntil(!pktin);
51470298 2969 ret = process_userpass_input(ssh, in, inlen);
0405e71f 2970 } while (ret == 0);
2971 if (ret < 0)
2972 cleanup_exit(0);
51470298 2973 c_write_str(ssh, "\r\n");
32874aea 2974 }
2975 } else {
86916870 2976 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
51470298 2977 s->username[sizeof(s->username)-1] = '\0';
374330e2 2978 }
fb09bf1c 2979
51470298 2980 send_packet(ssh, SSH1_CMSG_USER, PKT_STR, s->username, PKT_END);
c5e9c988 2981 {
51470298 2982 char userlog[22 + sizeof(s->username)];
2983 sprintf(userlog, "Sent username \"%s\"", s->username);
c5e9c988 2984 logevent(userlog);
32874aea 2985 if (flags & FLAG_INTERACTIVE &&
2986 (!((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)))) {
3c8e959b 2987 strcat(userlog, "\r\n");
51470298 2988 c_write_str(ssh, userlog);
3c8e959b 2989 }
c5e9c988 2990 }
374330e2 2991 }
2992
ff3187f6 2993 crWaitUntil(pktin);
374330e2 2994
51470298 2995 if ((ssh->remote_bugs & BUG_CHOKES_ON_RSA)) {
0df73905 2996 /* We must not attempt PK auth. Pretend we've already tried it. */
51470298 2997 s->tried_publickey = s->tried_agent = 1;
0df73905 2998 } else {
51470298 2999 s->tried_publickey = s->tried_agent = 0;
0df73905 3000 }
51470298 3001 s->tis_auth_refused = s->ccard_auth_refused = 0;
86916870 3002 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
9a30e26b 3003 if (!filename_is_null(ssh->cfg.keyfile)) {
3004 if (!rsakey_pubblob(&ssh->cfg.keyfile,
222d54dc 3005 &s->publickey_blob, &s->publickey_bloblen, NULL))
51470298 3006 s->publickey_blob = NULL;
396778f1 3007 } else
51470298 3008 s->publickey_blob = NULL;
7cca0d81 3009
ff3187f6 3010 while (pktin->type == SSH1_SMSG_FAILURE) {
51470298 3011 s->pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
614a20a0 3012
51470298 3013 if (agent_exists() && !s->tried_agent) {
32874aea 3014 /*
3015 * Attempt RSA authentication using Pageant.
3016 */
32874aea 3017 void *r;
3018
51470298 3019 s->authed = FALSE;
3020 s->tried_agent = 1;
32874aea 3021 logevent("Pageant is running. Requesting keys.");
3022
3023 /* Request the keys held by the agent. */
51470298 3024 PUT_32BIT(s->request, 1);
3025 s->request[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES;
839f10db 3026 if (!agent_query(s->request, 5, &r, &s->responselen,
3027 ssh_agent_callback, ssh)) {
3028 do {
3029 crReturn(0);
ff3187f6 3030 if (pktin) {
839f10db 3031 bombout(("Unexpected data from server while waiting"
3032 " for agent response"));
3033 crStop(0);
3034 }
ff3187f6 3035 } while (pktin || inlen > 0);
839f10db 3036 r = ssh->agent_response;
3037 s->responselen = ssh->agent_response_len;
3038 }
51470298 3039 s->response = (unsigned char *) r;
3040 if (s->response && s->responselen >= 5 &&
3041 s->response[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER) {
3042 s->p = s->response + 5;
3043 s->nkeys = GET_32BIT(s->p);
3044 s->p += 4;
fb983202 3045 logeventf(ssh, "Pageant has %d SSH1 keys", s->nkeys);
51470298 3046 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
fb983202 3047 logeventf(ssh, "Trying Pageant key #%d", s->keyi);
51470298 3048 if (s->publickey_blob &&
3049 !memcmp(s->p, s->publickey_blob,
3050 s->publickey_bloblen)) {
396778f1 3051 logevent("This key matches configured key file");
51470298 3052 s->tried_publickey = 1;
396778f1 3053 }
51470298 3054 s->p += 4;
0016d70b 3055 {
3056 int n, ok = FALSE;
3057 do { /* do while (0) to make breaking easy */
3058 n = ssh1_read_bignum
3059 (s->p, s->responselen-(s->p-s->response),
3060 &s->key.exponent);
3061 if (n < 0)
3062 break;
3063 s->p += n;
3064 n = ssh1_read_bignum
3065 (s->p, s->responselen-(s->p-s->response),
3066 &s->key.modulus);
3067 if (n < 0)
3068 break;
3069 s->p += n;
3070 if (s->responselen - (s->p-s->response) < 4)
3071 break;
3072 s->commentlen = GET_32BIT(s->p);
3073 s->p += 4;
3074 if (s->responselen - (s->p-s->response) <
3075 s->commentlen)
3076 break;
3077 s->commentp = (char *)s->p;
3078 s->p += s->commentlen;
3079 ok = TRUE;
3080 } while (0);
3081 if (!ok) {
3082 logevent("Pageant key list packet was truncated");
3083 break;
3084 }
3085 }
51470298 3086 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
3087 PKT_BIGNUM, s->key.modulus, PKT_END);
ff3187f6 3088 crWaitUntil(pktin);
3089 if (pktin->type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
32874aea 3090 logevent("Key refused");
3091 continue;
3092 }
3093 logevent("Received RSA challenge");
ff3187f6 3094 if ((s->challenge = ssh1_pkt_getmp(pktin)) == NULL) {
0016d70b 3095 bombout(("Server's RSA challenge was badly formatted"));
3096 crStop(0);
3097 }
3098
32874aea 3099 {
3100 char *agentreq, *q, *ret;
2d466ffd 3101 void *vret;
32874aea 3102 int len, retlen;
3103 len = 1 + 4; /* message type, bit count */
51470298 3104 len += ssh1_bignum_length(s->key.exponent);
3105 len += ssh1_bignum_length(s->key.modulus);
3106 len += ssh1_bignum_length(s->challenge);
32874aea 3107 len += 16; /* session id */
3108 len += 4; /* response format */
3d88e64d 3109 agentreq = snewn(4 + len, char);
32874aea 3110 PUT_32BIT(agentreq, len);
3111 q = agentreq + 4;
3112 *q++ = SSH1_AGENTC_RSA_CHALLENGE;
51470298 3113 PUT_32BIT(q, bignum_bitcount(s->key.modulus));
32874aea 3114 q += 4;
51470298 3115 q += ssh1_write_bignum(q, s->key.exponent);
3116 q += ssh1_write_bignum(q, s->key.modulus);
3117 q += ssh1_write_bignum(q, s->challenge);
3118 memcpy(q, s->session_id, 16);
32874aea 3119 q += 16;
3120 PUT_32BIT(q, 1); /* response format */
839f10db 3121 if (!agent_query(agentreq, len + 4, &vret, &retlen,
3122 ssh_agent_callback, ssh)) {
3123 sfree(agentreq);
3124 do {
3125 crReturn(0);
ff3187f6 3126 if (pktin) {
839f10db 3127 bombout(("Unexpected data from server"
3128 " while waiting for agent"
3129 " response"));
3130 crStop(0);
3131 }
ff3187f6 3132 } while (pktin || inlen > 0);
839f10db 3133 vret = ssh->agent_response;
3134 retlen = ssh->agent_response_len;
3135 } else
3136 sfree(agentreq);
2d466ffd 3137 ret = vret;
32874aea 3138 if (ret) {
3139 if (ret[4] == SSH1_AGENT_RSA_RESPONSE) {
3140 logevent("Sending Pageant's response");
51470298 3141 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
32874aea 3142 PKT_DATA, ret + 5, 16,
3143 PKT_END);
3144 sfree(ret);
ff3187f6 3145 crWaitUntil(pktin);
3146 if (pktin->type == SSH1_SMSG_SUCCESS) {
32874aea 3147 logevent
3148 ("Pageant's response accepted");
3149 if (flags & FLAG_VERBOSE) {
51470298 3150 c_write_str(ssh, "Authenticated using"
3151 " RSA key \"");
3152 c_write(ssh, s->commentp,
3153 s->commentlen);
3154 c_write_str(ssh, "\" from agent\r\n");
32874aea 3155 }
51470298 3156 s->authed = TRUE;
32874aea 3157 } else
3158 logevent
3159 ("Pageant's response not accepted");
3160 } else {
3161 logevent
3162 ("Pageant failed to answer challenge");
3163 sfree(ret);
3164 }
3165 } else {
3166 logevent("No reply received from Pageant");
3167 }
3168 }
51470298 3169 freebn(s->key.exponent);
3170 freebn(s->key.modulus);
3171 freebn(s->challenge);
3172 if (s->authed)
32874aea 3173 break;
3174 }
29b1d0b3 3175 sfree(s->response);
32874aea 3176 }
51470298 3177 if (s->authed)
32874aea 3178 break;
3179 }
9a30e26b 3180 if (!filename_is_null(ssh->cfg.keyfile) && !s->tried_publickey)
51470298 3181 s->pwpkt_type = SSH1_CMSG_AUTH_RSA;
32874aea 3182
86916870 3183 if (ssh->cfg.try_tis_auth &&
51470298 3184 (s->supported_auths_mask & (1 << SSH1_AUTH_TIS)) &&
3185 !s->tis_auth_refused) {
3186 s->pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
32874aea 3187 logevent("Requested TIS authentication");
51470298 3188 send_packet(ssh, SSH1_CMSG_AUTH_TIS, PKT_END);
ff3187f6 3189 crWaitUntil(pktin);
3190 if (pktin->type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
32874aea 3191 logevent("TIS authentication declined");
3192 if (flags & FLAG_INTERACTIVE)
51470298 3193 c_write_str(ssh, "TIS authentication refused.\r\n");
3194 s->tis_auth_refused = 1;
614a20a0 3195 continue;
32874aea 3196 } else {
0016d70b 3197 char *challenge;
3198 int challengelen;
3199
ff3187f6 3200 ssh_pkt_getstring(pktin, &challenge, &challengelen);
0016d70b 3201 if (!challenge) {
3202 bombout(("TIS challenge packet was badly formed"));
3203 crStop(0);
3204 }
32874aea 3205 logevent("Received TIS challenge");
51470298 3206 if (challengelen > sizeof(s->prompt) - 1)
3207 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
0016d70b 3208 memcpy(s->prompt, challenge, challengelen);
614a20a0 3209 /* Prompt heuristic comes from OpenSSH */
51470298 3210 strncpy(s->prompt + challengelen,
3211 memchr(s->prompt, '\n', challengelen) ?
614a20a0 3212 "": "\r\nResponse: ",
51470298 3213 (sizeof s->prompt) - challengelen);
3214 s->prompt[(sizeof s->prompt) - 1] = '\0';
32874aea 3215 }
3216 }
86916870 3217 if (ssh->cfg.try_tis_auth &&
51470298 3218 (s->supported_auths_mask & (1 << SSH1_AUTH_CCARD)) &&
3219 !s->ccard_auth_refused) {
3220 s->pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
32874aea 3221 logevent("Requested CryptoCard authentication");
51470298 3222 send_packet(ssh, SSH1_CMSG_AUTH_CCARD, PKT_END);
ff3187f6 3223 crWaitUntil(pktin);
3224 if (pktin->type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
32874aea 3225 logevent("CryptoCard authentication declined");
51470298 3226 c_write_str(ssh, "CryptoCard authentication refused.\r\n");
3227 s->ccard_auth_refused = 1;
614a20a0 3228 continue;
32874aea 3229 } else {
0016d70b 3230 char *challenge;
3231 int challengelen;
3232
ff3187f6 3233 ssh_pkt_getstring(pktin, &challenge, &challengelen);
0016d70b 3234 if (!challenge) {
3235 bombout(("CryptoCard challenge packet was badly formed"));
3236 crStop(0);
3237 }
32874aea 3238 logevent("Received CryptoCard challenge");
51470298 3239 if (challengelen > sizeof(s->prompt) - 1)
3240 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
0016d70b 3241 memcpy(s->prompt, challenge, challengelen);
51470298 3242 strncpy(s->prompt + challengelen,
3243 memchr(s->prompt, '\n', challengelen) ?
614a20a0 3244 "" : "\r\nResponse: ",
51470298 3245 sizeof(s->prompt) - challengelen);
3246 s->prompt[sizeof(s->prompt) - 1] = '\0';
32874aea 3247 }
3248 }
51470298 3249 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
3250 sprintf(s->prompt, "%.90s@%.90s's password: ",
3251 s->username, ssh->savedhost);
32874aea 3252 }
51470298 3253 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
32874aea 3254 char *comment = NULL;
231ee168 3255 int type;
32874aea 3256 if (flags & FLAG_VERBOSE)
51470298 3257 c_write_str(ssh, "Trying public key authentication.\r\n");
6c6d9ed9 3258 logeventf(ssh, "Trying public key \"%s\"",
3259 filename_to_str(&ssh->cfg.keyfile));
9a30e26b 3260 type = key_type(&ssh->cfg.keyfile);
231ee168 3261 if (type != SSH_KEYTYPE_SSH1) {
fb983202 3262 char *msg = dupprintf("Key is of wrong type (%s)",
3263 key_type_to_str(type));
3264 logevent(msg);
3265 c_write_str(ssh, msg);
51470298 3266 c_write_str(ssh, "\r\n");
fb983202 3267 sfree(msg);
51470298 3268 s->tried_publickey = 1;
231ee168 3269 continue;
3270 }
9a30e26b 3271 if (!rsakey_encrypted(&ssh->cfg.keyfile, &comment)) {
32874aea 3272 if (flags & FLAG_VERBOSE)
51470298 3273 c_write_str(ssh, "No passphrase required.\r\n");
32874aea 3274 goto tryauth;
3275 }
51470298 3276 sprintf(s->prompt, "Passphrase for key \"%.100s\": ", comment);
32874aea 3277 sfree(comment);
3278 }
a52f067e 3279
614a20a0 3280 /*
3281 * Show password prompt, having first obtained it via a TIS
3282 * or CryptoCard exchange if we're doing TIS or CryptoCard
3283 * authentication.
3284 */
fa17a66e 3285 if (ssh_get_line) {
51470298 3286 if (!ssh_get_line(s->prompt, s->password,
3287 sizeof(s->password), TRUE)) {
32874aea 3288 /*
3289 * get_line failed to get a password (for example
3290 * because one was supplied on the command line
3291 * which has already failed to work). Terminate.
3292 */
51470298 3293 send_packet(ssh, SSH1_MSG_DISCONNECT,
2bc6a386 3294 PKT_STR, "No more passwords available to try",
3295 PKT_END);
247308b5 3296 logevent("Unable to authenticate");
a8327734 3297 connection_fatal(ssh->frontend, "Unable to authenticate");
ac934965 3298 ssh->close_expected = TRUE;
3bb2f322 3299 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 3300 crStop(1);
32874aea 3301 }
fb09bf1c 3302 } else {
614a20a0 3303 /* Prompt may have come from server. We've munged it a bit, so
3304 * we know it to be zero-terminated at least once. */
51470298 3305 int ret; /* need not be saved over crReturn */
3306 c_write_untrusted(ssh, s->prompt, strlen(s->prompt));
3307 s->pos = 0;
0405e71f 3308
51470298 3309 setup_userpass_input(ssh, s->password, sizeof(s->password), 0);
0405e71f 3310 do {
ff3187f6 3311 crWaitUntil(!pktin);
51470298 3312 ret = process_userpass_input(ssh, in, inlen);
0405e71f 3313 } while (ret == 0);
3314 if (ret < 0)
3315 cleanup_exit(0);
51470298 3316 c_write_str(ssh, "\r\n");
32874aea 3317 }
3318
3319 tryauth:
51470298 3320 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
32874aea 3321 /*
3322 * Try public key authentication with the specified
3323 * key file.
3324 */
51470298 3325 s->tried_publickey = 1;
3326
3327 {
222d54dc 3328 const char *error = NULL;
3329 int ret = loadrsakey(&ssh->cfg.keyfile, &s->key, s->password,
3330 &error);
51470298 3331 if (ret == 0) {
3332 c_write_str(ssh, "Couldn't load private key from ");
9fab77dc 3333 c_write_str(ssh, filename_to_str(&ssh->cfg.keyfile));
222d54dc 3334 c_write_str(ssh, " (");
3335 c_write_str(ssh, error);
3336 c_write_str(ssh, ").\r\n");
51470298 3337 continue; /* go and try password */
3338 }
3339 if (ret == -1) {
3340 c_write_str(ssh, "Wrong passphrase.\r\n");
3341 s->tried_publickey = 0;
3342 continue; /* try again */
3343 }
32874aea 3344 }
3345
3346 /*
3347 * Send a public key attempt.
3348 */
51470298 3349 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
3350 PKT_BIGNUM, s->key.modulus, PKT_END);
32874aea 3351
ff3187f6 3352 crWaitUntil(pktin);
3353 if (pktin->type == SSH1_SMSG_FAILURE) {
51470298 3354 c_write_str(ssh, "Server refused our public key.\r\n");
32874aea 3355 continue; /* go and try password */
3356 }
ff3187f6 3357 if (pktin->type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
6b5cf8b4 3358 bombout(("Bizarre response to offer of public key"));
7ffdbc1a 3359 crStop(0);
32874aea 3360 }
32874aea 3361
51470298 3362 {
3363 int i;
3364 unsigned char buffer[32];
3365 Bignum challenge, response;
3366
ff3187f6 3367 if ((challenge = ssh1_pkt_getmp(pktin)) == NULL) {
0016d70b 3368 bombout(("Server's RSA challenge was badly formatted"));
3369 crStop(0);
3370 }
51470298 3371 response = rsadecrypt(challenge, &s->key);
3372 freebn(s->key.private_exponent);/* burn the evidence */
32874aea 3373
51470298 3374 for (i = 0; i < 32; i++) {
3375 buffer[i] = bignum_byte(response, 31 - i);
3376 }
3377
3378 MD5Init(&md5c);
3379 MD5Update(&md5c, buffer, 32);
3380 MD5Update(&md5c, s->session_id, 16);
3381 MD5Final(buffer, &md5c);
32874aea 3382
51470298 3383 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
3384 PKT_DATA, buffer, 16, PKT_END);
3385
3386 freebn(challenge);
3387 freebn(response);
3388 }
32874aea 3389
ff3187f6 3390 crWaitUntil(pktin);
3391 if (pktin->type == SSH1_SMSG_FAILURE) {
32874aea 3392 if (flags & FLAG_VERBOSE)
51470298 3393 c_write_str(ssh, "Failed to authenticate with"
3394 " our public key.\r\n");
32874aea 3395 continue; /* go and try password */
ff3187f6 3396 } else if (pktin->type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 3397 bombout(("Bizarre response to RSA authentication response"));
7ffdbc1a 3398 crStop(0);
32874aea 3399 }
3400
3401 break; /* we're through! */
3402 } else {
51470298 3403 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
32874aea 3404 /*
3405 * Defence against traffic analysis: we send a
3406 * whole bunch of packets containing strings of
3407 * different lengths. One of these strings is the
3408 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3409 * The others are all random data in
3410 * SSH1_MSG_IGNORE packets. This way a passive
3411 * listener can't tell which is the password, and
3412 * hence can't deduce the password length.
3413 *
3414 * Anybody with a password length greater than 16
3415 * bytes is going to have enough entropy in their
3416 * password that a listener won't find it _that_
3417 * much help to know how long it is. So what we'll
3418 * do is:
3419 *
3420 * - if password length < 16, we send 15 packets
3421 * containing string lengths 1 through 15
3422 *
3423 * - otherwise, we let N be the nearest multiple
3424 * of 8 below the password length, and send 8
3425 * packets containing string lengths N through
3426 * N+7. This won't obscure the order of
3427 * magnitude of the password length, but it will
3428 * introduce a bit of extra uncertainty.
3429 *
3430 * A few servers (the old 1.2.18 through 1.2.22)
3431 * can't deal with SSH1_MSG_IGNORE. For these
3432 * servers, we need an alternative defence. We make
3433 * use of the fact that the password is interpreted
3434 * as a C string: so we can append a NUL, then some
3435 * random data.
bd358db1 3436 *
3437 * One server (a Cisco one) can deal with neither
3438 * SSH1_MSG_IGNORE _nor_ a padded password string.
3439 * For this server we are left with no defences
3440 * against password length sniffing.
32874aea 3441 */
51470298 3442 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE)) {
b17c8428 3443 /*
3444 * The server can deal with SSH1_MSG_IGNORE, so
3445 * we can use the primary defence.
3446 */
32874aea 3447 int bottom, top, pwlen, i;
3448 char *randomstr;
3449
51470298 3450 pwlen = strlen(s->password);
32874aea 3451 if (pwlen < 16) {
3452 bottom = 0; /* zero length passwords are OK! :-) */
3453 top = 15;
3454 } else {
3455 bottom = pwlen & ~7;
3456 top = bottom + 7;
3457 }
3458
3459 assert(pwlen >= bottom && pwlen <= top);
3460
3d88e64d 3461 randomstr = snewn(top + 1, char);
32874aea 3462
3463 for (i = bottom; i <= top; i++) {
9a10ecf4 3464 if (i == pwlen) {
51470298 3465 defer_packet(ssh, s->pwpkt_type,
9a10ecf4 3466 PKTT_PASSWORD, PKT_STR, s->password,
3467 PKTT_OTHER, PKT_END);
3468 } else {
32874aea 3469 for (j = 0; j < i; j++) {
3470 do {
3471 randomstr[j] = random_byte();
3472 } while (randomstr[j] == '\0');
3473 }
3474 randomstr[i] = '\0';
51470298 3475 defer_packet(ssh, SSH1_MSG_IGNORE,
32874aea 3476 PKT_STR, randomstr, PKT_END);
3477 }
3478 }
bd358db1 3479 logevent("Sending password with camouflage packets");
51470298 3480 ssh_pkt_defersend(ssh);
679539d7 3481 sfree(randomstr);
bd358db1 3482 }
51470298 3483 else if (!(ssh->remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
b17c8428 3484 /*
3485 * The server can't deal with SSH1_MSG_IGNORE
3486 * but can deal with padded passwords, so we
3487 * can use the secondary defence.
3488 */
bd358db1 3489 char string[64];
51470298 3490 char *ss;
bd358db1 3491 int len;
3492
51470298 3493 len = strlen(s->password);
bd358db1 3494 if (len < sizeof(string)) {
51470298 3495 ss = string;
3496 strcpy(string, s->password);
bd358db1 3497 len++; /* cover the zero byte */
3498 while (len < sizeof(string)) {
3499 string[len++] = (char) random_byte();
3500 }
3501 } else {
51470298 3502 ss = s->password;
bd358db1 3503 }
3504 logevent("Sending length-padded password");
9a10ecf4 3505 send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
3506 PKT_INT, len, PKT_DATA, ss, len,
3507 PKTT_OTHER, PKT_END);
bd358db1 3508 } else {
3509 /*
3510 * The server has _both_
3511 * BUG_CHOKES_ON_SSH1_IGNORE and
3512 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3513 * therefore nothing we can do.
3514 */
3515 int len;
51470298 3516 len = strlen(s->password);
bd358db1 3517 logevent("Sending unpadded password");
9a10ecf4 3518 send_packet(ssh, s->pwpkt_type,
3519 PKTT_PASSWORD, PKT_INT, len,
3520 PKT_DATA, s->password, len,
3521 PKTT_OTHER, PKT_END);
32874aea 3522 }
3523 } else {
9a10ecf4 3524 send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
3525 PKT_STR, s->password, PKTT_OTHER, PKT_END);
32874aea 3526 }
3527 }
c5e9c988 3528 logevent("Sent password");
51470298 3529 memset(s->password, 0, strlen(s->password));
ff3187f6 3530 crWaitUntil(pktin);
3531 if (pktin->type == SSH1_SMSG_FAILURE) {
32874aea 3532 if (flags & FLAG_VERBOSE)
51470298 3533 c_write_str(ssh, "Access denied\r\n");
c5e9c988 3534 logevent("Authentication refused");
ff3187f6 3535 } else if (pktin->type != SSH1_SMSG_SUCCESS) {
3536 bombout(("Strange packet received, type %d", pktin->type));
7ffdbc1a 3537 crStop(0);
374330e2 3538 }
3539 }
3540
c5e9c988 3541 logevent("Authentication successful");
3542
fb09bf1c 3543 crFinish(1);
3544}
3545
32874aea 3546void sshfwd_close(struct ssh_channel *c)
3547{
51470298 3548 Ssh ssh = c->ssh;
3549
36f94d1f 3550 if (ssh->state != SSH_STATE_SESSION) {
3551 assert(ssh->state == SSH_STATE_CLOSED);
3552 return;
3553 }
3554
80e48603 3555 if (c && !c->closes) {
4ed34d25 3556 /*
64d6ff88 3557 * If halfopen is true, we have sent
4ed34d25 3558 * CHANNEL_OPEN for this channel, but it hasn't even been
3559 * acknowledged by the server. So we must set a close flag
3560 * on it now, and then when the server acks the channel
3561 * open, we can close it then.
3562 */
64d6ff88 3563 if (!c->halfopen) {
51470298 3564 if (ssh->version == 1) {
3565 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid,
4ed34d25 3566 PKT_END);
3567 } else {
ff3187f6 3568 struct Packet *pktout;
3569 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
3570 ssh2_pkt_adduint32(pktout, c->remoteid);
3571 ssh2_pkt_send(ssh, pktout);
4ed34d25 3572 }
32874aea 3573 }
0357890f 3574 c->closes = 1; /* sent MSG_CLOSE */
32874aea 3575 if (c->type == CHAN_X11) {
3576 c->u.x11.s = NULL;
d74d141c 3577 logevent("Forwarded X11 connection terminated");
4ed34d25 3578 } else if (c->type == CHAN_SOCKDATA ||
3579 c->type == CHAN_SOCKDATA_DORMANT) {
d74d141c 3580 c->u.pfd.s = NULL;
3581 logevent("Forwarded port closed");
32874aea 3582 }
3583 }
3584}
3585
5471d09a 3586int sshfwd_write(struct ssh_channel *c, char *buf, int len)
32874aea 3587{
51470298 3588 Ssh ssh = c->ssh;
3589
36f94d1f 3590 if (ssh->state != SSH_STATE_SESSION) {
3591 assert(ssh->state == SSH_STATE_CLOSED);
3592 return 0;
3593 }
3594
51470298 3595 if (ssh->version == 1) {
3596 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
32874aea 3597 PKT_INT, c->remoteid,
9a10ecf4 3598 PKTT_DATA,
3599 PKT_INT, len, PKT_DATA, buf, len,
3600 PKTT_OTHER, PKT_END);
5471d09a 3601 /*
3602 * In SSH1 we can return 0 here - implying that forwarded
3603 * connections are never individually throttled - because
3604 * the only circumstance that can cause throttling will be
3605 * the whole SSH connection backing up, in which case
3606 * _everything_ will be throttled as a whole.
3607 */
3608 return 0;
783415f8 3609 } else {
32874aea 3610 ssh2_add_channel_data(c, buf, len);
5471d09a 3611 return ssh2_try_send(c);
3612 }
3613}
3614
3615void sshfwd_unthrottle(struct ssh_channel *c, int bufsize)
3616{
51470298 3617 Ssh ssh = c->ssh;
3618
36f94d1f 3619 if (ssh->state != SSH_STATE_SESSION) {
3620 assert(ssh->state == SSH_STATE_CLOSED);
3621 return;
3622 }
3623
51470298 3624 if (ssh->version == 1) {
5471d09a 3625 if (c->v.v1.throttling && bufsize < SSH1_BUFFER_LIMIT) {
3626 c->v.v1.throttling = 0;
51470298 3627 ssh1_throttle(ssh, -1);
5471d09a 3628 }
3629 } else {
3630 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
783415f8 3631 }
9c964e85 3632}
3633
06fadff5 3634static void ssh_queueing_handler(Ssh ssh, struct Packet *pktin)
3635{
3636 struct queued_handler *qh = ssh->qhead;
3637
3638 assert(qh != NULL);
3639
3640 assert(pktin->type == qh->msg1 || pktin->type == qh->msg2);
3641
3642 if (qh->msg1 > 0) {
3643 assert(ssh->packet_dispatch[qh->msg1] == ssh_queueing_handler);
3644 ssh->packet_dispatch[qh->msg1] = NULL;
3645 }
3646 if (qh->msg2 > 0) {
3647 assert(ssh->packet_dispatch[qh->msg2] == ssh_queueing_handler);
3648 ssh->packet_dispatch[qh->msg2] = NULL;
3649 }
3650
3651 if (qh->next) {
3652 ssh->qhead = qh->next;
3653
3654 if (ssh->qhead->msg1 > 0) {
3655 assert(ssh->packet_dispatch[ssh->qhead->msg1] == NULL);
3656 ssh->packet_dispatch[ssh->qhead->msg1] = ssh_queueing_handler;
3657 }
3658 if (ssh->qhead->msg2 > 0) {
3659 assert(ssh->packet_dispatch[ssh->qhead->msg2] == NULL);
3660 ssh->packet_dispatch[ssh->qhead->msg2] = ssh_queueing_handler;
3661 }
3662 } else {
3663 ssh->qhead = ssh->qtail = NULL;
3664 ssh->packet_dispatch[pktin->type] = NULL;
3665 }
3666
3667 qh->handler(ssh, pktin, qh->ctx);
3668
3669 sfree(qh);
3670}
3671
3672static void ssh_queue_handler(Ssh ssh, int msg1, int msg2,
3673 chandler_fn_t handler, void *ctx)
3674{
3675 struct queued_handler *qh;
3676
3677 qh = snew(struct queued_handler);
3678 qh->msg1 = msg1;
3679 qh->msg2 = msg2;
3680 qh->handler = handler;
3681 qh->ctx = ctx;
3682 qh->next = NULL;
3683
3684 if (ssh->qtail == NULL) {
3685 ssh->qhead = qh;
3686
3687 if (qh->msg1 > 0) {
3688 assert(ssh->packet_dispatch[qh->msg1] == NULL);
3689 ssh->packet_dispatch[qh->msg1] = ssh_queueing_handler;
3690 }
3691 if (qh->msg2 > 0) {
3692 assert(ssh->packet_dispatch[qh->msg2] == NULL);
3693 ssh->packet_dispatch[qh->msg2] = ssh_queueing_handler;
3694 }
3695 } else {
3696 ssh->qtail->next = qh;
3697 }
3698 ssh->qtail = qh;
3699}
3700
3701static void ssh_rportfwd_succfail(Ssh ssh, struct Packet *pktin, void *ctx)
3702{
3703 struct ssh_rportfwd *rpf, *pf = (struct ssh_rportfwd *)ctx;
3704
3705 if (pktin->type == (ssh->version == 1 ? SSH1_SMSG_SUCCESS :
3706 SSH2_MSG_REQUEST_SUCCESS)) {
3707 logeventf(ssh, "Remote port forwarding from %s enabled",
3708 pf->sportdesc);
3709 } else {
3710 logeventf(ssh, "Remote port forwarding from %s refused",
3711 pf->sportdesc);
3712
3713 rpf = del234(ssh->rportfwds, pf);
3714 assert(rpf == pf);
fda2feb1 3715 free_rportfwd(pf);
06fadff5 3716 }
3717}
3718
3719static void ssh_setup_portfwd(Ssh ssh, const Config *cfg)
3720{
84328ddb 3721 const char *portfwd_strptr = cfg->portfwd;
3722 struct ssh_portfwd *epf;
3723 int i;
06fadff5 3724
fda2feb1 3725 if (!ssh->portfwds) {
3726 ssh->portfwds = newtree234(ssh_portcmp);
3727 } else {
3728 /*
3729 * Go through the existing port forwardings and tag them
84328ddb 3730 * with status==DESTROY. Any that we want to keep will be
3731 * re-enabled (status==KEEP) as we go through the
3732 * configuration and find out which bits are the same as
3733 * they were before.
fda2feb1 3734 */
3735 struct ssh_portfwd *epf;
3736 int i;
3737 for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
84328ddb 3738 epf->status = DESTROY;
fda2feb1 3739 }
3740
06fadff5 3741 while (*portfwd_strptr) {
84328ddb 3742 char address_family, type;
3743 int sport,dport,sserv,dserv;
3744 char sports[256], dports[256], saddr[256], host[256];
3745 int n;
3746
05581745 3747 address_family = 'A';
3748 type = 'L';
84328ddb 3749 if (*portfwd_strptr == 'A' ||
3750 *portfwd_strptr == '4' ||
3751 *portfwd_strptr == '6')
3752 address_family = *portfwd_strptr++;
3753 if (*portfwd_strptr == 'L' ||
3754 *portfwd_strptr == 'R' ||
3755 *portfwd_strptr == 'D')
3756 type = *portfwd_strptr++;
05581745 3757
06fadff5 3758 saddr[0] = '\0';
05581745 3759
06fadff5 3760 n = 0;
3761 while (*portfwd_strptr && *portfwd_strptr != '\t') {
3762 if (*portfwd_strptr == ':') {
3763 /*
3764 * We've seen a colon in the middle of the
3765 * source port number. This means that
3766 * everything we've seen until now is the
3767 * source _address_, so we'll move it into
3768 * saddr and start sports from the beginning
3769 * again.
3770 */
3771 portfwd_strptr++;
3772 sports[n] = '\0';
3773 if (ssh->version == 1 && type == 'R') {
3774 logeventf(ssh, "SSH1 cannot handle remote source address "
3775 "spec \"%s\"; ignoring", sports);
3776 } else
3777 strcpy(saddr, sports);
3778 n = 0;
3779 }
3780 if (n < 255) sports[n++] = *portfwd_strptr++;
3781 }
3782 sports[n] = 0;
3783 if (type != 'D') {
3784 if (*portfwd_strptr == '\t')
3785 portfwd_strptr++;
3786 n = 0;
3787 while (*portfwd_strptr && *portfwd_strptr != ':') {
3788 if (n < 255) host[n++] = *portfwd_strptr++;
3789 }
3790 host[n] = 0;
3791 if (*portfwd_strptr == ':')
3792 portfwd_strptr++;
3793 n = 0;
3794 while (*portfwd_strptr) {
3795 if (n < 255) dports[n++] = *portfwd_strptr++;
3796 }
3797 dports[n] = 0;
3798 portfwd_strptr++;
3799 dport = atoi(dports);
3800 dserv = 0;
3801 if (dport == 0) {
3802 dserv = 1;
3803 dport = net_service_lookup(dports);
3804 if (!dport) {
3805 logeventf(ssh, "Service lookup failed for destination"
3806 " port \"%s\"", dports);
3807 }
3808 }
3809 } else {
3810 while (*portfwd_strptr) portfwd_strptr++;
3811 dport = dserv = -1;
3812 portfwd_strptr++; /* eat the NUL and move to next one */
3813 }
3814 sport = atoi(sports);
3815 sserv = 0;
3816 if (sport == 0) {
3817 sserv = 1;
3818 sport = net_service_lookup(sports);
3819 if (!sport) {
3820 logeventf(ssh, "Service lookup failed for source"
3821 " port \"%s\"", sports);
3822 }
3823 }
3824 if (sport && dport) {
3825 /* Set up a description of the source port. */
fda2feb1 3826 struct ssh_portfwd *pfrec, *epfrec;
fda2feb1 3827
3828 pfrec = snew(struct ssh_portfwd);
3829 pfrec->type = type;
3830 pfrec->saddr = *saddr ? dupstr(saddr) : NULL;
3fe92132 3831 pfrec->sserv = sserv ? dupstr(sports) : NULL;
fda2feb1 3832 pfrec->sport = sport;
84328ddb 3833 pfrec->daddr = *host ? dupstr(host) : NULL;
3fe92132 3834 pfrec->dserv = dserv ? dupstr(dports) : NULL;
fda2feb1 3835 pfrec->dport = dport;
3836 pfrec->local = NULL;
3837 pfrec->remote = NULL;
05581745 3838 pfrec->addressfamily = (address_family == '4' ? ADDRTYPE_IPV4 :
3839 address_family == '6' ? ADDRTYPE_IPV6 :
3840 ADDRTYPE_UNSPEC);
fda2feb1 3841
3842 epfrec = add234(ssh->portfwds, pfrec);
3843 if (epfrec != pfrec) {
3844 /*
3845 * We already have a port forwarding with precisely
3846 * these parameters. Hence, no need to do anything;
84328ddb 3847 * simply tag the existing one as KEEP.
fda2feb1 3848 */
84328ddb 3849 epfrec->status = KEEP;
fda2feb1 3850 free_portfwd(pfrec);
84328ddb 3851 } else {
3852 pfrec->status = CREATE;
3853 }
3854 }
3855 }
3856
3857 /*
3858 * Now go through and destroy any port forwardings which were
3859 * not re-enabled.
3860 */
3861 for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
3862 if (epf->status == DESTROY) {
3863 char *message;
3864
3865 message = dupprintf("%s port forwarding from %s%s%d",
3866 epf->type == 'L' ? "local" :
3867 epf->type == 'R' ? "remote" : "dynamic",
3868 epf->saddr ? epf->saddr : "",
3869 epf->saddr ? ":" : "",
3870 epf->sport);
3871
3872 if (epf->type != 'D') {
3873 char *msg2 = dupprintf("%s to %s:%d", message,
3874 epf->daddr, epf->dport);
3875 sfree(message);
3876 message = msg2;
3877 }
3878
3879 logeventf(ssh, "Cancelling %s", message);
3880 sfree(message);
3881
3882 if (epf->remote) {
3883 struct ssh_rportfwd *rpf = epf->remote;
3884 struct Packet *pktout;
3885
3886 /*
3887 * Cancel the port forwarding at the server
3888 * end.
3889 */
3890 if (ssh->version == 1) {
3891 /*
3892 * We cannot cancel listening ports on the
3893 * server side in SSH1! There's no message
3894 * to support it. Instead, we simply remove
3895 * the rportfwd record from the local end
3896 * so that any connections the server tries
3897 * to make on it are rejected.
3898 */
3899 } else {
3900 pktout = ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST);
3901 ssh2_pkt_addstring(pktout, "cancel-tcpip-forward");
3902 ssh2_pkt_addbool(pktout, 0);/* _don't_ want reply */
3903 if (epf->saddr) {
3904 ssh2_pkt_addstring(pktout, epf->saddr);
3905 } else if (ssh->cfg.rport_acceptall) {
3906 ssh2_pkt_addstring(pktout, "0.0.0.0");
3907 } else {
3908 ssh2_pkt_addstring(pktout, "127.0.0.1");
3909 }
3910 ssh2_pkt_adduint32(pktout, epf->sport);
3911 ssh2_pkt_send(ssh, pktout);
3912 }
3913
3914 del234(ssh->rportfwds, rpf);
3915 free_rportfwd(rpf);
3916 } else if (epf->local) {
3917 pfd_terminate(epf->local);
3918 }
3919
3920 delpos234(ssh->portfwds, i);
3921 free_portfwd(epf);
3922 i--; /* so we don't skip one in the list */
3923 }
3924
3925 /*
3926 * And finally, set up any new port forwardings (status==CREATE).
3927 */
3928 for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
3929 if (epf->status == CREATE) {
3930 char *sportdesc, *dportdesc;
3fe92132 3931 sportdesc = dupprintf("%s%s%s%s%d%s",
84328ddb 3932 epf->saddr ? epf->saddr : "",
3933 epf->saddr ? ":" : "",
3fe92132 3934 epf->sserv ? epf->sserv : "",
3935 epf->sserv ? "(" : "",
3936 epf->sport,
3937 epf->sserv ? ")" : "");
84328ddb 3938 if (epf->type == 'D') {
3939 dportdesc = NULL;
3940 } else {
3fe92132 3941 dportdesc = dupprintf("%s:%s%s%d%s",
3942 epf->daddr,
3943 epf->dserv ? epf->dserv : "",
3944 epf->dserv ? "(" : "",
3945 epf->dport,
3946 epf->dserv ? ")" : "");
84328ddb 3947 }
05581745 3948
84328ddb 3949 if (epf->type == 'L') {
3950 const char *err = pfd_addforward(epf->daddr, epf->dport,
3951 epf->saddr, epf->sport,
3952 ssh, &ssh->cfg,
3953 &epf->local,
3954 epf->addressfamily);
3955
3956 logeventf(ssh, "Local %sport %s forwarding to %s%s%s",
3957 epf->addressfamily == ADDRTYPE_IPV4 ? "IPv4 " :
3958 epf->addressfamily == ADDRTYPE_IPV6 ? "IPv6 " : "",
3959 sportdesc, dportdesc,
3960 err ? " failed: " : "", err ? err : "");
3961 } else if (epf->type == 'D') {
06fadff5 3962 const char *err = pfd_addforward(NULL, -1,
84328ddb 3963 epf->saddr, epf->sport,
3964 ssh, &ssh->cfg,
3965 &epf->local,
3966 epf->addressfamily);
3967
3968 logeventf(ssh, "Local %sport %s SOCKS dynamic forwarding%s%s",
3969 epf->addressfamily == ADDRTYPE_IPV4 ? "IPv4 " :
3970 epf->addressfamily == ADDRTYPE_IPV6 ? "IPv6 " : "",
3971 sportdesc,
3972 err ? " failed: " : "", err ? err : "");
06fadff5 3973 } else {
3974 struct ssh_rportfwd *pf;
3975
3976 /*
3977 * Ensure the remote port forwardings tree exists.
3978 */
3979 if (!ssh->rportfwds) {
3980 if (ssh->version == 1)
3981 ssh->rportfwds = newtree234(ssh_rportcmp_ssh1);
3982 else
3983 ssh->rportfwds = newtree234(ssh_rportcmp_ssh2);
3984 }
3985
3986 pf = snew(struct ssh_rportfwd);
84328ddb 3987 strncpy(pf->dhost, epf->daddr, lenof(pf->dhost)-1);
3988 pf->dhost[lenof(pf->dhost)-1] = '\0';
3989 pf->dport = epf->dport;
3990 pf->sport = epf->sport;
06fadff5 3991 if (add234(ssh->rportfwds, pf) != pf) {
3992 logeventf(ssh, "Duplicate remote port forwarding to %s:%d",
84328ddb 3993 epf->daddr, epf->dport);
06fadff5 3994 sfree(pf);
3995 } else {
3996 logeventf(ssh, "Requesting remote port %s"
84328ddb 3997 " forward to %s", sportdesc, dportdesc);
06fadff5 3998
3999 pf->sportdesc = sportdesc;
4000 sportdesc = NULL;
84328ddb 4001 epf->remote = pf;
4002 pf->pfrec = epf;
06fadff5 4003
4004 if (ssh->version == 1) {
4005 send_packet(ssh, SSH1_CMSG_PORT_FORWARD_REQUEST,
84328ddb 4006 PKT_INT, epf->sport,
4007 PKT_STR, epf->daddr,
4008 PKT_INT, epf->dport,
06fadff5 4009 PKT_END);
4010 ssh_queue_handler(ssh, SSH1_SMSG_SUCCESS,
4011 SSH1_SMSG_FAILURE,
4012 ssh_rportfwd_succfail, pf);
4013 } else {
4014 struct Packet *pktout;
4015 pktout = ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST);
4016 ssh2_pkt_addstring(pktout, "tcpip-forward");
4017 ssh2_pkt_addbool(pktout, 1);/* want reply */
84328ddb 4018 if (epf->saddr) {
4019 ssh2_pkt_addstring(pktout, epf->saddr);
06fadff5 4020 } else if (ssh->cfg.rport_acceptall) {
4021 ssh2_pkt_addstring(pktout, "0.0.0.0");
4022 } else {
4023 ssh2_pkt_addstring(pktout, "127.0.0.1");
4024 }
84328ddb 4025 ssh2_pkt_adduint32(pktout, epf->sport);
06fadff5 4026 ssh2_pkt_send(ssh, pktout);
4027
4028 ssh_queue_handler(ssh, SSH2_MSG_REQUEST_SUCCESS,
4029 SSH2_MSG_REQUEST_FAILURE,
4030 ssh_rportfwd_succfail, pf);
4031 }
4032 }
4033 }
4034 sfree(sportdesc);
84328ddb 4035 sfree(dportdesc);
06fadff5 4036 }
06fadff5 4037}
4038
51df0ab5 4039static void ssh1_smsg_stdout_stderr_data(Ssh ssh, struct Packet *pktin)
4040{
4041 char *string;
4042 int stringlen, bufsize;
4043
4044 ssh_pkt_getstring(pktin, &string, &stringlen);
4045 if (string == NULL) {
4046 bombout(("Incoming terminal data packet was badly formed"));
4047 return;
4048 }
4049
4050 bufsize = from_backend(ssh->frontend, pktin->type == SSH1_SMSG_STDERR_DATA,
4051 string, stringlen);
4052 if (!ssh->v1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
4053 ssh->v1_stdout_throttling = 1;
4054 ssh1_throttle(ssh, +1);
4055 }
4056}
4057
4058static void ssh1_smsg_x11_open(Ssh ssh, struct Packet *pktin)
4059{
4060 /* Remote side is trying to open a channel to talk to our
4061 * X-Server. Give them back a local channel number. */
4062 struct ssh_channel *c;
4063 int remoteid = ssh_pkt_getuint32(pktin);
4064
4065 logevent("Received X11 connect request");
4066 /* Refuse if X11 forwarding is disabled. */
4067 if (!ssh->X11_fwd_enabled) {
4068 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4069 PKT_INT, remoteid, PKT_END);
4070 logevent("Rejected X11 connect request");
4071 } else {
4072 c = snew(struct ssh_channel);
4073 c->ssh = ssh;
4074
4075 if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
4076 ssh->x11auth, NULL, -1, &ssh->cfg) != NULL) {
4077 logevent("Opening X11 forward connection failed");
4078 sfree(c);
4079 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4080 PKT_INT, remoteid, PKT_END);
4081 } else {
4082 logevent
4083 ("Opening X11 forward connection succeeded");
4084 c->remoteid = remoteid;
64d6ff88 4085 c->halfopen = FALSE;
51df0ab5 4086 c->localid = alloc_channel_id(ssh);
4087 c->closes = 0;
4088 c->v.v1.throttling = 0;
4089 c->type = CHAN_X11; /* identify channel type */
4090 add234(ssh->channels, c);
4091 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
4092 PKT_INT, c->remoteid, PKT_INT,
4093 c->localid, PKT_END);
4094 logevent("Opened X11 forward channel");
4095 }
4096 }
4097}
4098
4099static void ssh1_smsg_agent_open(Ssh ssh, struct Packet *pktin)
4100{
4101 /* Remote side is trying to open a channel to talk to our
4102 * agent. Give them back a local channel number. */
4103 struct ssh_channel *c;
4104 int remoteid = ssh_pkt_getuint32(pktin);
4105
4106 /* Refuse if agent forwarding is disabled. */
4107 if (!ssh->agentfwd_enabled) {
4108 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4109 PKT_INT, remoteid, PKT_END);
4110 } else {
4111 c = snew(struct ssh_channel);
4112 c->ssh = ssh;
4113 c->remoteid = remoteid;
64d6ff88 4114 c->halfopen = FALSE;
51df0ab5 4115 c->localid = alloc_channel_id(ssh);
4116 c->closes = 0;
4117 c->v.v1.throttling = 0;
4118 c->type = CHAN_AGENT; /* identify channel type */
4119 c->u.a.lensofar = 0;
4120 add234(ssh->channels, c);
4121 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
4122 PKT_INT, c->remoteid, PKT_INT, c->localid,
4123 PKT_END);
4124 }
4125}
4126
4127static void ssh1_msg_port_open(Ssh ssh, struct Packet *pktin)
4128{
4129 /* Remote side is trying to open a channel to talk to a
4130 * forwarded port. Give them back a local channel number. */
4131 struct ssh_channel *c;
05581745 4132 struct ssh_rportfwd pf, *pfp;
51df0ab5 4133 int remoteid;
4134 int hostsize, port;
fb983202 4135 char *host;
51df0ab5 4136 const char *e;
4137 c = snew(struct ssh_channel);
4138 c->ssh = ssh;
4139
4140 remoteid = ssh_pkt_getuint32(pktin);
4141 ssh_pkt_getstring(pktin, &host, &hostsize);
4142 port = ssh_pkt_getuint32(pktin);
4143
4144 if (hostsize >= lenof(pf.dhost))
4145 hostsize = lenof(pf.dhost)-1;
4146 memcpy(pf.dhost, host, hostsize);
4147 pf.dhost[hostsize] = '\0';
4148 pf.dport = port;
05581745 4149 pfp = find234(ssh->rportfwds, &pf, NULL);
51df0ab5 4150
05581745 4151 if (pfp == NULL) {
fb983202 4152 logeventf(ssh, "Rejected remote port open request for %s:%d",
4153 pf.dhost, port);
51df0ab5 4154 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4155 PKT_INT, remoteid, PKT_END);
4156 } else {
fb983202 4157 logeventf(ssh, "Received remote port open request for %s:%d",
4158 pf.dhost, port);
51df0ab5 4159 e = pfd_newconnect(&c->u.pfd.s, pf.dhost, port,
05581745 4160 c, &ssh->cfg, pfp->pfrec->addressfamily);
51df0ab5 4161 if (e != NULL) {
fb983202 4162 logeventf(ssh, "Port open failed: %s", e);
51df0ab5 4163 sfree(c);
4164 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4165 PKT_INT, remoteid, PKT_END);
4166 } else {
4167 c->remoteid = remoteid;
64d6ff88 4168 c->halfopen = FALSE;
51df0ab5 4169 c->localid = alloc_channel_id(ssh);
4170 c->closes = 0;
4171 c->v.v1.throttling = 0;
4172 c->type = CHAN_SOCKDATA; /* identify channel type */
4173 add234(ssh->channels, c);
4174 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
4175 PKT_INT, c->remoteid, PKT_INT,
4176 c->localid, PKT_END);
4177 logevent("Forwarded port opened successfully");
4178 }
4179 }
4180}
4181
4182static void ssh1_msg_channel_open_confirmation(Ssh ssh, struct Packet *pktin)
4183{
4184 unsigned int remoteid = ssh_pkt_getuint32(pktin);
4185 unsigned int localid = ssh_pkt_getuint32(pktin);
4186 struct ssh_channel *c;
4187
4188 c = find234(ssh->channels, &remoteid, ssh_channelfind);
4189 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
4190 c->remoteid = localid;
64d6ff88 4191 c->halfopen = FALSE;
51df0ab5 4192 c->type = CHAN_SOCKDATA;
4193 c->v.v1.throttling = 0;
4194 pfd_confirm(c->u.pfd.s);
4195 }
4196
4197 if (c && c->closes) {
4198 /*
4199 * We have a pending close on this channel,
4200 * which we decided on before the server acked
4201 * the channel open. So now we know the
4202 * remoteid, we can close it again.
4203 */
4204 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE,
4205 PKT_INT, c->remoteid, PKT_END);
4206 }
4207}
4208
4209static void ssh1_msg_channel_open_failure(Ssh ssh, struct Packet *pktin)
4210{
4211 unsigned int remoteid = ssh_pkt_getuint32(pktin);
4212 struct ssh_channel *c;
4213
4214 c = find234(ssh->channels, &remoteid, ssh_channelfind);
4215 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
4216 logevent("Forwarded connection refused by server");
4217 pfd_close(c->u.pfd.s);
4218 del234(ssh->channels, c);
4219 sfree(c);
4220 }
4221}
4222
4223static void ssh1_msg_channel_close(Ssh ssh, struct Packet *pktin)
4224{
4225 /* Remote side closes a channel. */
4226 unsigned i = ssh_pkt_getuint32(pktin);
4227 struct ssh_channel *c;
4228 c = find234(ssh->channels, &i, ssh_channelfind);
64d6ff88 4229 if (c && !c->halfopen) {
51df0ab5 4230 int closetype;
4231 closetype =
4232 (pktin->type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
4233
4234 if ((c->closes == 0) && (c->type == CHAN_X11)) {
4235 logevent("Forwarded X11 connection terminated");
4236 assert(c->u.x11.s != NULL);
4237 x11_close(c->u.x11.s);
4238 c->u.x11.s = NULL;
4239 }
4240 if ((c->closes == 0) && (c->type == CHAN_SOCKDATA)) {
4241 logevent("Forwarded port closed");
4242 assert(c->u.pfd.s != NULL);
4243 pfd_close(c->u.pfd.s);
4244 c->u.pfd.s = NULL;
4245 }
4246
4247 c->closes |= (closetype << 2); /* seen this message */
4248 if (!(c->closes & closetype)) {
4249 send_packet(ssh, pktin->type, PKT_INT, c->remoteid,
4250 PKT_END);
4251 c->closes |= closetype; /* sent it too */
4252 }
4253
4254 if (c->closes == 15) {
4255 del234(ssh->channels, c);
4256 sfree(c);
4257 }
4258 } else {
4259 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
4260 pktin->type == SSH1_MSG_CHANNEL_CLOSE ? "" :
4261 "_CONFIRMATION", c ? "half-open" : "nonexistent",
4262 i));
4263 }
4264}
4265
4266static void ssh1_msg_channel_data(Ssh ssh, struct Packet *pktin)
4267{
4268 /* Data sent down one of our channels. */
4269 int i = ssh_pkt_getuint32(pktin);
4270 char *p;
6d44acc9 4271 int len;
51df0ab5 4272 struct ssh_channel *c;
4273
4274 ssh_pkt_getstring(pktin, &p, &len);
4275
4276 c = find234(ssh->channels, &i, ssh_channelfind);
4277 if (c) {
4278 int bufsize = 0;
4279 switch (c->type) {
4280 case CHAN_X11:
4281 bufsize = x11_send(c->u.x11.s, p, len);
4282 break;
4283 case CHAN_SOCKDATA:
4284 bufsize = pfd_send(c->u.pfd.s, p, len);
4285 break;
4286 case CHAN_AGENT:
4287 /* Data for an agent message. Buffer it. */
4288 while (len > 0) {
4289 if (c->u.a.lensofar < 4) {
aa63ab7e 4290 unsigned int l = min(4 - c->u.a.lensofar, len);
51df0ab5 4291 memcpy(c->u.a.msglen + c->u.a.lensofar, p,
4292 l);
4293 p += l;
4294 len -= l;
4295 c->u.a.lensofar += l;
4296 }
4297 if (c->u.a.lensofar == 4) {
4298 c->u.a.totallen =
4299 4 + GET_32BIT(c->u.a.msglen);
4300 c->u.a.message = snewn(c->u.a.totallen,
4301 unsigned char);
4302 memcpy(c->u.a.message, c->u.a.msglen, 4);
4303 }
4304 if (c->u.a.lensofar >= 4 && len > 0) {
aa63ab7e 4305 unsigned int l =
51df0ab5 4306 min(c->u.a.totallen - c->u.a.lensofar,
4307 len);
4308 memcpy(c->u.a.message + c->u.a.lensofar, p,
4309 l);
4310 p += l;
4311 len -= l;
4312 c->u.a.lensofar += l;
4313 }
4314 if (c->u.a.lensofar == c->u.a.totallen) {
4315 void *reply;
4316 int replylen;
4317 if (agent_query(c->u.a.message,
4318 c->u.a.totallen,
4319 &reply, &replylen,
4320 ssh_agentf_callback, c))
4321 ssh_agentf_callback(c, reply, replylen);
4322 sfree(c->u.a.message);
4323 c->u.a.lensofar = 0;
4324 }
4325 }
4326 bufsize = 0; /* agent channels never back up */
4327 break;
4328 }
4329 if (!c->v.v1.throttling && bufsize > SSH1_BUFFER_LIMIT) {
4330 c->v.v1.throttling = 1;
4331 ssh1_throttle(ssh, +1);
4332 }
4333 }
4334}
4335
4336static void ssh1_smsg_exit_status(Ssh ssh, struct Packet *pktin)
4337{
51df0ab5 4338 ssh->exitcode = ssh_pkt_getuint32(pktin);
fb983202 4339 logeventf(ssh, "Server sent command exit status %d", ssh->exitcode);
51df0ab5 4340 send_packet(ssh, SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
4341 /*
4342 * In case `helpful' firewalls or proxies tack
4343 * extra human-readable text on the end of the
4344 * session which we might mistake for another
4345 * encrypted packet, we close the session once
4346 * we've sent EXIT_CONFIRMATION.
4347 */
ac934965 4348 ssh->close_expected = TRUE;
51df0ab5 4349 ssh_closing((Plug)ssh, NULL, 0, 0);
4350}
4351
b09eaa88 4352static void do_ssh1_connection(Ssh ssh, unsigned char *in, int inlen,
4353 struct Packet *pktin)
32874aea 4354{
b09eaa88 4355 crBegin(ssh->do_ssh1_connection_crstate);
fb09bf1c 4356
51df0ab5 4357 ssh->packet_dispatch[SSH1_SMSG_STDOUT_DATA] =
4358 ssh->packet_dispatch[SSH1_SMSG_STDERR_DATA] =
4359 ssh1_smsg_stdout_stderr_data;
4360
4361 ssh->packet_dispatch[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION] =
4362 ssh1_msg_channel_open_confirmation;
4363 ssh->packet_dispatch[SSH1_MSG_CHANNEL_OPEN_FAILURE] =
4364 ssh1_msg_channel_open_failure;
4365 ssh->packet_dispatch[SSH1_MSG_CHANNEL_CLOSE] =
4366 ssh->packet_dispatch[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION] =
4367 ssh1_msg_channel_close;
4368 ssh->packet_dispatch[SSH1_MSG_CHANNEL_DATA] = ssh1_msg_channel_data;
4369 ssh->packet_dispatch[SSH1_SMSG_EXIT_STATUS] = ssh1_smsg_exit_status;
4370
86916870 4371 if (ssh->cfg.agentfwd && agent_exists()) {
32874aea 4372 logevent("Requesting agent forwarding");
51470298 4373 send_packet(ssh, SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
32874aea 4374 do {
4375 crReturnV;
ff3187f6 4376 } while (!pktin);
4377 if (pktin->type != SSH1_SMSG_SUCCESS
4378 && pktin->type != SSH1_SMSG_FAILURE) {
6b5cf8b4 4379 bombout(("Protocol confusion"));
7ffdbc1a 4380 crStopV;
ff3187f6 4381 } else if (pktin->type == SSH1_SMSG_FAILURE) {
32874aea 4382 logevent("Agent forwarding refused");
4383 } else {
4384 logevent("Agent forwarding enabled");
51470298 4385 ssh->agentfwd_enabled = TRUE;
51df0ab5 4386 ssh->packet_dispatch[SSH1_SMSG_AGENT_OPEN] = ssh1_smsg_agent_open;
db7d555c 4387 }
dacbd0e8 4388 }
4389
86916870 4390 if (ssh->cfg.x11_forward) {
32874aea 4391 char proto[20], data[64];
4392 logevent("Requesting X11 forwarding");
302121de 4393 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
86916870 4394 data, sizeof(data), ssh->cfg.x11_auth);
4395 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
51470298 4396 if (ssh->v1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) {
4397 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
32874aea 4398 PKT_STR, proto, PKT_STR, data,
86916870 4399 PKT_INT, x11_get_screen_number(ssh->cfg.x11_display),
421d6835 4400 PKT_END);
32874aea 4401 } else {
51470298 4402 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
32874aea 4403 PKT_STR, proto, PKT_STR, data, PKT_END);
4404 }
4405 do {
4406 crReturnV;
ff3187f6 4407 } while (!pktin);
4408 if (pktin->type != SSH1_SMSG_SUCCESS
4409 && pktin->type != SSH1_SMSG_FAILURE) {
6b5cf8b4 4410 bombout(("Protocol confusion"));
7ffdbc1a 4411 crStopV;
ff3187f6 4412 } else if (pktin->type == SSH1_SMSG_FAILURE) {
32874aea 4413 logevent("X11 forwarding refused");
4414 } else {
4415 logevent("X11 forwarding enabled");
51470298 4416 ssh->X11_fwd_enabled = TRUE;
51df0ab5 4417 ssh->packet_dispatch[SSH1_SMSG_X11_OPEN] = ssh1_smsg_x11_open;
9c964e85 4418 }
4419 }
4420
06fadff5 4421 ssh_setup_portfwd(ssh, &ssh->cfg);
4422 ssh->packet_dispatch[SSH1_MSG_PORT_OPEN] = ssh1_msg_port_open;
d74d141c 4423
86916870 4424 if (!ssh->cfg.nopty) {
a5dd8467 4425 /* Unpick the terminal-speed string. */
4426 /* XXX perhaps we should allow no speeds to be sent. */
db219738 4427 ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
4428 sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
a5dd8467 4429 /* Send the pty request. */
51470298 4430 send_packet(ssh, SSH1_CMSG_REQUEST_PTY,
86916870 4431 PKT_STR, ssh->cfg.termtype,
51470298 4432 PKT_INT, ssh->term_height,
4433 PKT_INT, ssh->term_width,
a5dd8467 4434 PKT_INT, 0, PKT_INT, 0, /* width,height in pixels */
db219738 4435 PKT_CHAR, 192, PKT_INT, ssh->ispeed, /* TTY_OP_ISPEED */
4436 PKT_CHAR, 193, PKT_INT, ssh->ospeed, /* TTY_OP_OSPEED */
a5dd8467 4437 PKT_CHAR, 0, PKT_END);
51470298 4438 ssh->state = SSH_STATE_INTERMED;
32874aea 4439 do {
4440 crReturnV;
ff3187f6 4441 } while (!pktin);
4442 if (pktin->type != SSH1_SMSG_SUCCESS
4443 && pktin->type != SSH1_SMSG_FAILURE) {
6b5cf8b4 4444 bombout(("Protocol confusion"));
7ffdbc1a 4445 crStopV;
ff3187f6 4446 } else if (pktin->type == SSH1_SMSG_FAILURE) {
51470298 4447 c_write_str(ssh, "Server refused to allocate pty\r\n");
4448 ssh->editing = ssh->echoing = 1;
32874aea 4449 }
a5dd8467 4450 logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
db219738 4451 ssh->ospeed, ssh->ispeed);
0965bee0 4452 } else {
51470298 4453 ssh->editing = ssh->echoing = 1;
374330e2 4454 }
4455
86916870 4456 if (ssh->cfg.compression) {
51470298 4457 send_packet(ssh, SSH1_CMSG_REQUEST_COMPRESSION, PKT_INT, 6, PKT_END);
32874aea 4458 do {
4459 crReturnV;
ff3187f6 4460 } while (!pktin);
4461 if (pktin->type != SSH1_SMSG_SUCCESS
4462 && pktin->type != SSH1_SMSG_FAILURE) {
6b5cf8b4 4463 bombout(("Protocol confusion"));
7ffdbc1a 4464 crStopV;
ff3187f6 4465 } else if (pktin->type == SSH1_SMSG_FAILURE) {
51470298 4466 c_write_str(ssh, "Server refused to compress\r\n");
32874aea 4467 }
4ba9b64b 4468 logevent("Started compression");
51470298 4469 ssh->v1_compressing = TRUE;
5366aed8 4470 ssh->cs_comp_ctx = zlib_compress_init();
4471 logevent("Initialised zlib (RFC1950) compression");
4472 ssh->sc_comp_ctx = zlib_decompress_init();
4473 logevent("Initialised zlib (RFC1950) decompression");
4ba9b64b 4474 }
4475
fd5e5847 4476 /*
4477 * Start the shell or command.
4478 *
4479 * Special case: if the first-choice command is an SSH2
4480 * subsystem (hence not usable here) and the second choice
4481 * exists, we fall straight back to that.
4482 */
4483 {
86916870 4484 char *cmd = ssh->cfg.remote_cmd_ptr;
fd5e5847 4485
86916870 4486 if (ssh->cfg.ssh_subsys && ssh->cfg.remote_cmd_ptr2) {
4487 cmd = ssh->cfg.remote_cmd_ptr2;
51470298 4488 ssh->fallback_cmd = TRUE;
fd5e5847 4489 }
4490 if (*cmd)
51470298 4491 send_packet(ssh, SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END);
fd5e5847 4492 else
51470298 4493 send_packet(ssh, SSH1_CMSG_EXEC_SHELL, PKT_END);
fd5e5847 4494 logevent("Started session");
4495 }
374330e2 4496
51470298 4497 ssh->state = SSH_STATE_SESSION;
4498 if (ssh->size_needed)
4499 ssh_size(ssh, ssh->term_width, ssh->term_height);
4500 if (ssh->eof_needed)
4501 ssh_special(ssh, TS_EOF);
374330e2 4502
b9d7bcad 4503 if (ssh->ldisc)
4504 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
51470298 4505 ssh->send_ok = 1;
4506 ssh->channels = newtree234(ssh_channelcmp);
374330e2 4507 while (1) {
d74d141c 4508
51df0ab5 4509 /*
4510 * By this point, most incoming packets are already being
4511 * handled by the dispatch table, and we need only pay
4512 * attention to the unusual ones.
4513 */
0357890f 4514
51df0ab5 4515 crReturnV;
4516 if (pktin) {
4517 if (pktin->type == SSH1_SMSG_SUCCESS) {
972a41c8 4518 /* may be from EXEC_SHELL on some servers */
ff3187f6 4519 } else if (pktin->type == SSH1_SMSG_FAILURE) {
972a41c8 4520 /* may be from EXEC_SHELL on some servers
374330e2 4521 * if no pty is available or in other odd cases. Ignore */
374330e2 4522 } else {
ff3187f6 4523 bombout(("Strange packet received: type %d", pktin->type));
7ffdbc1a 4524 crStopV;
374330e2 4525 }
4526 } else {
8df7a775 4527 while (inlen > 0) {
4528 int len = min(inlen, 512);
9a10ecf4 4529 send_packet(ssh, SSH1_CMSG_STDIN_DATA, PKTT_DATA,
4530 PKT_INT, len, PKT_DATA, in, len,
4531 PKTT_OTHER, PKT_END);
8df7a775 4532 in += len;
4533 inlen -= len;
4534 }
374330e2 4535 }
4536 }
4537
4538 crFinishV;
4539}
4540
4541/*
b09eaa88 4542 * Handle the top-level SSH2 protocol.
4543 */
4544static void ssh1_msg_debug(Ssh ssh, struct Packet *pktin)
4545{
fb983202 4546 char *msg;
b09eaa88 4547 int msglen;
4548
4549 ssh_pkt_getstring(pktin, &msg, &msglen);
fb983202 4550 logeventf(ssh, "Remote debug message: %.*s", msglen, msg);
b09eaa88 4551}
4552
4553static void ssh1_msg_disconnect(Ssh ssh, struct Packet *pktin)
4554{
4555 /* log reason code in disconnect message */
4556 char *msg;
4557 int msglen;
4558
4559 ssh_pkt_getstring(pktin, &msg, &msglen);
4560 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen, msg));
4561}
4562
409bfa77 4563static void ssh_msg_ignore(Ssh ssh, struct Packet *pktin)
b09eaa88 4564{
4565 /* Do nothing, because we're ignoring it! Duhh. */
4566}
4567
4568static void ssh1_protocol_setup(Ssh ssh)
4569{
4570 int i;
4571
4572 /*
4573 * Most messages are handled by the coroutines.
4574 */
4575 for (i = 0; i < 256; i++)
4576 ssh->packet_dispatch[i] = NULL;
4577
4578 /*
4579 * These special message types we install handlers for.
4580 */
4581 ssh->packet_dispatch[SSH1_MSG_DISCONNECT] = ssh1_msg_disconnect;
4582 ssh->packet_dispatch[SSH1_MSG_IGNORE] = ssh_msg_ignore;
4583 ssh->packet_dispatch[SSH1_MSG_DEBUG] = ssh1_msg_debug;
4584}
4585
1c1a7262 4586static void ssh1_protocol(Ssh ssh, void *vin, int inlen,
b09eaa88 4587 struct Packet *pktin)
4588{
1c1a7262 4589 unsigned char *in=(unsigned char*)vin;
b09eaa88 4590 if (ssh->state == SSH_STATE_CLOSED)
4591 return;
4592
4593 if (pktin && ssh->packet_dispatch[pktin->type]) {
4594 ssh->packet_dispatch[pktin->type](ssh, pktin);
4595 return;
4596 }
4597
4598 if (!ssh->protocol_initial_phase_done) {
4599 if (do_ssh1_login(ssh, in, inlen, pktin))
4600 ssh->protocol_initial_phase_done = TRUE;
4601 else
4602 return;
4603 }
4604
4605 do_ssh1_connection(ssh, in, inlen, pktin);
4606}
4607
4608/*
e5574168 4609 * Utility routine for decoding comma-separated strings in KEXINIT.
4610 */
32874aea 4611static int in_commasep_string(char *needle, char *haystack, int haylen)
4612{
57356d63 4613 int needlen;
4614 if (!needle || !haystack) /* protect against null pointers */
4615 return 0;
4616 needlen = strlen(needle);
e5574168 4617 while (1) {
32874aea 4618 /*
4619 * Is it at the start of the string?
4620 */
4621 if (haylen >= needlen && /* haystack is long enough */
4622 !memcmp(needle, haystack, needlen) && /* initial match */
4623 (haylen == needlen || haystack[needlen] == ',')
4624 /* either , or EOS follows */
4625 )
4626 return 1;
4627 /*
4628 * If not, search for the next comma and resume after that.
4629 * If no comma found, terminate.
4630 */
4631 while (haylen > 0 && *haystack != ',')
4632 haylen--, haystack++;
4633 if (haylen == 0)
4634 return 0;
4635 haylen--, haystack++; /* skip over comma itself */
e5574168 4636 }
4637}
4638
4639/*
b59743d5 4640 * Similar routine for checking whether we have the first string in a list.
4641 */
4642static int first_in_commasep_string(char *needle, char *haystack, int haylen)
4643{
4644 int needlen;
4645 if (!needle || !haystack) /* protect against null pointers */
4646 return 0;
4647 needlen = strlen(needle);
4648 /*
4649 * Is it at the start of the string?
4650 */
4651 if (haylen >= needlen && /* haystack is long enough */
4652 !memcmp(needle, haystack, needlen) && /* initial match */
4653 (haylen == needlen || haystack[needlen] == ',')
4654 /* either , or EOS follows */
4655 )
4656 return 1;
4657 return 0;
4658}
4659
4660
4661/*
d39f364a 4662 * SSH2 key creation method.
4663 */
d8baa528 4664static void ssh2_mkkey(Ssh ssh, Bignum K, unsigned char *H,
4665 unsigned char *sessid, char chr,
4666 unsigned char *keyspace)
32874aea 4667{
d39f364a 4668 SHA_State s;
4669 /* First 20 bytes. */
4670 SHA_Init(&s);
51470298 4671 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
088bde77 4672 sha_mpint(&s, K);
d39f364a 4673 SHA_Bytes(&s, H, 20);
4674 SHA_Bytes(&s, &chr, 1);
5e0d7cb8 4675 SHA_Bytes(&s, sessid, 20);
d39f364a 4676 SHA_Final(&s, keyspace);
4677 /* Next 20 bytes. */
4678 SHA_Init(&s);
51470298 4679 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
088bde77 4680 sha_mpint(&s, K);
d39f364a 4681 SHA_Bytes(&s, H, 20);
4682 SHA_Bytes(&s, keyspace, 20);
32874aea 4683 SHA_Final(&s, keyspace + 20);
d39f364a 4684}
4685
4686/*
7cca0d81 4687 * Handle the SSH2 transport layer.
e5574168 4688 */
1c1a7262 4689static int do_ssh2_transport(Ssh ssh, void *vin, int inlen,
ff3187f6 4690 struct Packet *pktin)
e5574168 4691{
1c1a7262 4692 unsigned char *in = (unsigned char *)vin;
51470298 4693 struct do_ssh2_transport_state {
4694 int nbits, pbits, warn;
4695 Bignum p, g, e, f, K;
4696 int kex_init_value, kex_reply_value;
4697 const struct ssh_mac **maclist;
4698 int nmacs;
4699 const struct ssh2_cipher *cscipher_tobe;
4700 const struct ssh2_cipher *sccipher_tobe;
4701 const struct ssh_mac *csmac_tobe;
4702 const struct ssh_mac *scmac_tobe;
4703 const struct ssh_compress *cscomp_tobe;
4704 const struct ssh_compress *sccomp_tobe;
4705 char *hostkeydata, *sigdata, *keystr, *fingerprint;
4706 int hostkeylen, siglen;
4707 void *hkey; /* actual host key */
4708 unsigned char exchange_hash[20];
83e7d008 4709 int n_preferred_kex;
4710 const struct ssh_kex *preferred_kex[KEX_MAX];
51470298 4711 int n_preferred_ciphers;
4712 const struct ssh2_ciphers *preferred_ciphers[CIPHER_MAX];
4713 const struct ssh_compress *preferred_comp;
e13bba36 4714 int got_session_id, activated_authconn;
ff3187f6 4715 struct Packet *pktout;
51470298 4716 };
4717 crState(do_ssh2_transport_state);
4718
4719 crBegin(ssh->do_ssh2_transport_crstate);
4720
4721 s->cscipher_tobe = s->sccipher_tobe = NULL;
4722 s->csmac_tobe = s->scmac_tobe = NULL;
4723 s->cscomp_tobe = s->sccomp_tobe = NULL;
4724
e13bba36 4725 s->got_session_id = s->activated_authconn = FALSE;
e5574168 4726
e13bba36 4727 /*
4728 * Be prepared to work around the buggy MAC problem.
4729 */
4730 if (ssh->remote_bugs & BUG_SSH2_HMAC)
4731 s->maclist = buggymacs, s->nmacs = lenof(buggymacs);
4732 else
4733 s->maclist = macs, s->nmacs = lenof(macs);
4734
4735 begin_key_exchange:
149d2abc 4736 ssh->pkt_ctx &= ~SSH2_PKTCTX_KEX_MASK;
51470298 4737 {
e13bba36 4738 int i, j, commalist_started;
4739
51470298 4740 /*
83e7d008 4741 * Set up the preferred key exchange. (NULL => warn below here)
4742 */
4743 s->n_preferred_kex = 0;
4744 for (i = 0; i < KEX_MAX; i++) {
4745 switch (ssh->cfg.ssh_kexlist[i]) {
4746 case KEX_DHGEX:
4747 s->preferred_kex[s->n_preferred_kex++] =
4748 &ssh_diffiehellman_gex;
4749 break;
4750 case KEX_DHGROUP14:
4751 s->preferred_kex[s->n_preferred_kex++] =
4752 &ssh_diffiehellman_group14;
4753 break;
4754 case KEX_DHGROUP1:
4755 s->preferred_kex[s->n_preferred_kex++] =
4756 &ssh_diffiehellman_group1;
4757 break;
4758 case CIPHER_WARN:
4759 /* Flag for later. Don't bother if it's the last in
4760 * the list. */
4761 if (i < KEX_MAX - 1) {
4762 s->preferred_kex[s->n_preferred_kex++] = NULL;
4763 }
4764 break;
4765 }
4766 }
83e7d008 4767
83e7d008 4768 /*
51470298 4769 * Set up the preferred ciphers. (NULL => warn below here)
4770 */
4771 s->n_preferred_ciphers = 0;
4772 for (i = 0; i < CIPHER_MAX; i++) {
86916870 4773 switch (ssh->cfg.ssh_cipherlist[i]) {
51470298 4774 case CIPHER_BLOWFISH:
4775 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_blowfish;
4776 break;
4777 case CIPHER_DES:
86916870 4778 if (ssh->cfg.ssh2_des_cbc) {
51470298 4779 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_des;
4780 }
4781 break;
4782 case CIPHER_3DES:
4783 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_3des;
4784 break;
4785 case CIPHER_AES:
4786 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_aes;
4787 break;
4788 case CIPHER_WARN:
4789 /* Flag for later. Don't bother if it's the last in
4790 * the list. */
4791 if (i < CIPHER_MAX - 1) {
4792 s->preferred_ciphers[s->n_preferred_ciphers++] = NULL;
4793 }
4794 break;
ca20bfcf 4795 }
ca20bfcf 4796 }
7591b9ff 4797
e13bba36 4798 /*
4799 * Set up preferred compression.
4800 */
4801 if (ssh->cfg.compression)
4802 s->preferred_comp = &ssh_zlib;
4803 else
4804 s->preferred_comp = &ssh_comp_none;
51470298 4805
4806 /*
590f6a5f 4807 * Enable queueing of outgoing auth- or connection-layer
4808 * packets while we are in the middle of a key exchange.
4809 */
4810 ssh->queueing = TRUE;
4811
4812 /*
9442dd57 4813 * Flag that KEX is in progress.
4814 */
4815 ssh->kex_in_progress = TRUE;
4816
4817 /*
51470298 4818 * Construct and send our key exchange packet.
4819 */
ff3187f6 4820 s->pktout = ssh2_pkt_init(SSH2_MSG_KEXINIT);
51470298 4821 for (i = 0; i < 16; i++)
ff3187f6 4822 ssh2_pkt_addbyte(s->pktout, (unsigned char) random_byte());
51470298 4823 /* List key exchange algorithms. */
ff3187f6 4824 ssh2_pkt_addstring_start(s->pktout);
83e7d008 4825 commalist_started = 0;
4826 for (i = 0; i < s->n_preferred_kex; i++) {
4827 const struct ssh_kex *k = s->preferred_kex[i];
4828 if (!k) continue; /* warning flag */
4829 if (commalist_started)
ff3187f6 4830 ssh2_pkt_addstring_str(s->pktout, ",");
83e7d008 4831 ssh2_pkt_addstring_str(s->pktout, s->preferred_kex[i]->name);
4832 commalist_started = 1;
32874aea 4833 }
51470298 4834 /* List server host key algorithms. */
ff3187f6 4835 ssh2_pkt_addstring_start(s->pktout);
51470298 4836 for (i = 0; i < lenof(hostkey_algs); i++) {
ff3187f6 4837 ssh2_pkt_addstring_str(s->pktout, hostkey_algs[i]->name);
51470298 4838 if (i < lenof(hostkey_algs) - 1)
ff3187f6 4839 ssh2_pkt_addstring_str(s->pktout, ",");
32874aea 4840 }
51470298 4841 /* List client->server encryption algorithms. */
ff3187f6 4842 ssh2_pkt_addstring_start(s->pktout);
83e7d008 4843 commalist_started = 0;
51470298 4844 for (i = 0; i < s->n_preferred_ciphers; i++) {
4845 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4846 if (!c) continue; /* warning flag */
4847 for (j = 0; j < c->nciphers; j++) {
83e7d008 4848 if (commalist_started)
ff3187f6 4849 ssh2_pkt_addstring_str(s->pktout, ",");
4850 ssh2_pkt_addstring_str(s->pktout, c->list[j]->name);
83e7d008 4851 commalist_started = 1;
51470298 4852 }
4853 }
4854 /* List server->client encryption algorithms. */
ff3187f6 4855 ssh2_pkt_addstring_start(s->pktout);
83e7d008 4856 commalist_started = 0;
51470298 4857 for (i = 0; i < s->n_preferred_ciphers; i++) {
4858 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4859 if (!c) continue; /* warning flag */
4860 for (j = 0; j < c->nciphers; j++) {
83e7d008 4861 if (commalist_started)
ff3187f6 4862 ssh2_pkt_addstring_str(s->pktout, ",");
4863 ssh2_pkt_addstring_str(s->pktout, c->list[j]->name);
83e7d008 4864 commalist_started = 1;
51470298 4865 }
4866 }
4867 /* List client->server MAC algorithms. */
ff3187f6 4868 ssh2_pkt_addstring_start(s->pktout);
51470298 4869 for (i = 0; i < s->nmacs; i++) {
ff3187f6 4870 ssh2_pkt_addstring_str(s->pktout, s->maclist[i]->name);
51470298 4871 if (i < s->nmacs - 1)
ff3187f6 4872 ssh2_pkt_addstring_str(s->pktout, ",");
51470298 4873 }
4874 /* List server->client MAC algorithms. */
ff3187f6 4875 ssh2_pkt_addstring_start(s->pktout);
51470298 4876 for (i = 0; i < s->nmacs; i++) {
ff3187f6 4877 ssh2_pkt_addstring_str(s->pktout, s->maclist[i]->name);
51470298 4878 if (i < s->nmacs - 1)
ff3187f6 4879 ssh2_pkt_addstring_str(s->pktout, ",");
51470298 4880 }
4881 /* List client->server compression algorithms. */
ff3187f6 4882 ssh2_pkt_addstring_start(s->pktout);
f6e0abe2 4883 assert(lenof(compressions) > 1);
ff3187f6 4884 ssh2_pkt_addstring_str(s->pktout, s->preferred_comp->name);
f6e0abe2 4885 for (i = 0; i < lenof(compressions); i++) {
4886 const struct ssh_compress *c = compressions[i];
4887 if (c != s->preferred_comp) {
ff3187f6 4888 ssh2_pkt_addstring_str(s->pktout, ",");
4889 ssh2_pkt_addstring_str(s->pktout, c->name);
f6e0abe2 4890 }
51470298 4891 }
4892 /* List server->client compression algorithms. */
ff3187f6 4893 ssh2_pkt_addstring_start(s->pktout);
f6e0abe2 4894 assert(lenof(compressions) > 1);
ff3187f6 4895 ssh2_pkt_addstring_str(s->pktout, s->preferred_comp->name);
f6e0abe2 4896 for (i = 0; i < lenof(compressions); i++) {
4897 const struct ssh_compress *c = compressions[i];
4898 if (c != s->preferred_comp) {
ff3187f6 4899 ssh2_pkt_addstring_str(s->pktout, ",");
4900 ssh2_pkt_addstring_str(s->pktout, c->name);
f6e0abe2 4901 }
51470298 4902 }
4903 /* List client->server languages. Empty list. */
ff3187f6 4904 ssh2_pkt_addstring_start(s->pktout);
51470298 4905 /* List server->client languages. Empty list. */
ff3187f6 4906 ssh2_pkt_addstring_start(s->pktout);
51470298 4907 /* First KEX packet does _not_ follow, because we're not that brave. */
ff3187f6 4908 ssh2_pkt_addbool(s->pktout, FALSE);
51470298 4909 /* Reserved. */
ff3187f6 4910 ssh2_pkt_adduint32(s->pktout, 0);
e5574168 4911 }
0db56f73 4912
51470298 4913 ssh->exhash = ssh->exhashbase;
ff3187f6 4914 sha_string(&ssh->exhash, s->pktout->data + 5, s->pktout->length - 5);
0db56f73 4915
590f6a5f 4916 ssh2_pkt_send_noqueue(ssh, s->pktout);
e5574168 4917
ff3187f6 4918 if (!pktin)
4919 crWaitUntil(pktin);
4920 if (pktin->length > 5)
4921 sha_string(&ssh->exhash, pktin->data + 5, pktin->length - 5);
e5574168 4922
4923 /*
4924 * Now examine the other side's KEXINIT to see what we're up
4925 * to.
4926 */
51470298 4927 {
4928 char *str;
b59743d5 4929 int i, j, len, guessok;
51470298 4930
ff3187f6 4931 if (pktin->type != SSH2_MSG_KEXINIT) {
6b5cf8b4 4932 bombout(("expected key exchange packet from server"));
7ffdbc1a 4933 crStop(0);
32874aea 4934 }
51470298 4935 ssh->kex = NULL;
4936 ssh->hostkey = NULL;
4937 s->cscipher_tobe = NULL;
4938 s->sccipher_tobe = NULL;
4939 s->csmac_tobe = NULL;
4940 s->scmac_tobe = NULL;
4941 s->cscomp_tobe = NULL;
4942 s->sccomp_tobe = NULL;
ff3187f6 4943 pktin->savedpos += 16; /* skip garbage cookie */
4944 ssh_pkt_getstring(pktin, &str, &len); /* key exchange algorithms */
83e7d008 4945 s->warn = 0;
4946 for (i = 0; i < s->n_preferred_kex; i++) {
4947 const struct ssh_kex *k = s->preferred_kex[i];
4948 if (!k) {
4949 s->warn = 1;
4950 } else if (in_commasep_string(k->name, str, len)) {
4951 ssh->kex = k;
4952 }
4953 if (ssh->kex) {
bb348ab1 4954 if (s->warn) {
4955 sk_set_frozen(ssh->s, 1);
83e7d008 4956 askalg(ssh->frontend, "key-exchange algorithm",
4957 ssh->kex->name);
bb348ab1 4958 sk_set_frozen(ssh->s, 0);
4959 }
51470298 4960 break;
4961 }
32874aea 4962 }
83e7d008 4963 if (!ssh->kex) {
4964 bombout(("Couldn't agree a key exchange algorithm (available: %s)",
4965 str ? str : "(null)"));
4966 crStop(0);
4967 }
b59743d5 4968 /*
4969 * Note that the server's guess is considered wrong if it doesn't match
4970 * the first algorithm in our list, even if it's still the algorithm
4971 * we end up using.
4972 */
4973 guessok =
4974 first_in_commasep_string(s->preferred_kex[0]->name, str, len);
ff3187f6 4975 ssh_pkt_getstring(pktin, &str, &len); /* host key algorithms */
51470298 4976 for (i = 0; i < lenof(hostkey_algs); i++) {
4977 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
4978 ssh->hostkey = hostkey_algs[i];
4979 break;
4980 }
4981 }
b59743d5 4982 guessok = guessok &&
4983 first_in_commasep_string(hostkey_algs[0]->name, str, len);
ff3187f6 4984 ssh_pkt_getstring(pktin, &str, &len); /* client->server cipher */
51470298 4985 s->warn = 0;
4986 for (i = 0; i < s->n_preferred_ciphers; i++) {
4987 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4988 if (!c) {
4989 s->warn = 1;
4990 } else {
4991 for (j = 0; j < c->nciphers; j++) {
4992 if (in_commasep_string(c->list[j]->name, str, len)) {
4993 s->cscipher_tobe = c->list[j];
4994 break;
4995 }
ca20bfcf 4996 }
32874aea 4997 }
51470298 4998 if (s->cscipher_tobe) {
bb348ab1 4999 if (s->warn) {
5000 sk_set_frozen(ssh->s, 1);
83e7d008 5001 askalg(ssh->frontend, "client-to-server cipher",
5002 s->cscipher_tobe->name);
bb348ab1 5003 sk_set_frozen(ssh->s, 0);
5004 }
51470298 5005 break;
5006 }
32874aea 5007 }
51470298 5008 if (!s->cscipher_tobe) {
6b5cf8b4 5009 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
57356d63 5010 str ? str : "(null)"));
7ffdbc1a 5011 crStop(0);
ca20bfcf 5012 }
0ef8f407 5013
ff3187f6 5014 ssh_pkt_getstring(pktin, &str, &len); /* server->client cipher */
51470298 5015 s->warn = 0;
5016 for (i = 0; i < s->n_preferred_ciphers; i++) {
5017 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
5018 if (!c) {
5019 s->warn = 1;
5020 } else {
5021 for (j = 0; j < c->nciphers; j++) {
5022 if (in_commasep_string(c->list[j]->name, str, len)) {
5023 s->sccipher_tobe = c->list[j];
5024 break;
5025 }
ca20bfcf 5026 }
32874aea 5027 }
51470298 5028 if (s->sccipher_tobe) {
bb348ab1 5029 if (s->warn) {
5030 sk_set_frozen(ssh->s, 1);
83e7d008 5031 askalg(ssh->frontend, "server-to-client cipher",
5032 s->sccipher_tobe->name);
bb348ab1 5033 sk_set_frozen(ssh->s, 0);
5034 }
51470298 5035 break;
5036 }
32874aea 5037 }
51470298 5038 if (!s->sccipher_tobe) {
6b5cf8b4 5039 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
57356d63 5040 str ? str : "(null)"));
7ffdbc1a 5041 crStop(0);
ca20bfcf 5042 }
0ef8f407 5043
ff3187f6 5044 ssh_pkt_getstring(pktin, &str, &len); /* client->server mac */
51470298 5045 for (i = 0; i < s->nmacs; i++) {
5046 if (in_commasep_string(s->maclist[i]->name, str, len)) {
5047 s->csmac_tobe = s->maclist[i];
5048 break;
5049 }
32874aea 5050 }
ff3187f6 5051 ssh_pkt_getstring(pktin, &str, &len); /* server->client mac */
51470298 5052 for (i = 0; i < s->nmacs; i++) {
5053 if (in_commasep_string(s->maclist[i]->name, str, len)) {
5054 s->scmac_tobe = s->maclist[i];
5055 break;
5056 }
32874aea 5057 }
ff3187f6 5058 ssh_pkt_getstring(pktin, &str, &len); /* client->server compression */
51470298 5059 for (i = 0; i < lenof(compressions) + 1; i++) {
5060 const struct ssh_compress *c =
5061 i == 0 ? s->preferred_comp : compressions[i - 1];
5062 if (in_commasep_string(c->name, str, len)) {
5063 s->cscomp_tobe = c;
5064 break;
5065 }
32874aea 5066 }
ff3187f6 5067 ssh_pkt_getstring(pktin, &str, &len); /* server->client compression */
51470298 5068 for (i = 0; i < lenof(compressions) + 1; i++) {
5069 const struct ssh_compress *c =
5070 i == 0 ? s->preferred_comp : compressions[i - 1];
5071 if (in_commasep_string(c->name, str, len)) {
5072 s->sccomp_tobe = c;
5073 break;
5074 }
32874aea 5075 }
b59743d5 5076 ssh_pkt_getstring(pktin, &str, &len); /* client->server language */
5077 ssh_pkt_getstring(pktin, &str, &len); /* server->client language */
5078 if (ssh2_pkt_getbool(pktin) && !guessok) /* first_kex_packet_follows */
5079 crWaitUntil(pktin); /* Ignore packet */
e5574168 5080 }
e5574168 5081
5082 /*
7bd5a860 5083 * Work out the number of bits of key we will need from the key
5084 * exchange. We start with the maximum key length of either
5085 * cipher...
5086 */
5087 {
32874aea 5088 int csbits, scbits;
7bd5a860 5089
51470298 5090 csbits = s->cscipher_tobe->keylen;
5091 scbits = s->sccipher_tobe->keylen;
5092 s->nbits = (csbits > scbits ? csbits : scbits);
7bd5a860 5093 }
5094 /* The keys only have 160-bit entropy, since they're based on
5095 * a SHA-1 hash. So cap the key size at 160 bits. */
51470298 5096 if (s->nbits > 160)
5097 s->nbits = 160;
7bd5a860 5098
5099 /*
a92dd380 5100 * If we're doing Diffie-Hellman group exchange, start by
5101 * requesting a group.
e5574168 5102 */
d1aaf71d 5103 if (!ssh->kex->pdata) {
32874aea 5104 logevent("Doing Diffie-Hellman group exchange");
51470298 5105 ssh->pkt_ctx |= SSH2_PKTCTX_DHGEX;
32874aea 5106 /*
5107 * Work out how big a DH group we will need to allow that
5108 * much data.
7bd5a860 5109 */
51470298 5110 s->pbits = 512 << ((s->nbits - 1) / 64);
ff3187f6 5111 s->pktout = ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST);
5112 ssh2_pkt_adduint32(s->pktout, s->pbits);
590f6a5f 5113 ssh2_pkt_send_noqueue(ssh, s->pktout);
32874aea 5114
ff3187f6 5115 crWaitUntil(pktin);
5116 if (pktin->type != SSH2_MSG_KEX_DH_GEX_GROUP) {
6b5cf8b4 5117 bombout(("expected key exchange group packet from server"));
7ffdbc1a 5118 crStop(0);
32874aea 5119 }
ff3187f6 5120 s->p = ssh2_pkt_getmp(pktin);
5121 s->g = ssh2_pkt_getmp(pktin);
5122 if (!s->p || !s->g) {
5123 bombout(("unable to read mp-ints from incoming group packet"));
5124 crStop(0);
5125 }
d1aaf71d 5126 ssh->kex_ctx = dh_setup_gex(s->p, s->g);
51470298 5127 s->kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
5128 s->kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY;
a92dd380 5129 } else {
d1aaf71d 5130 ssh->pkt_ctx |= SSH2_PKTCTX_DHGROUP;
5131 ssh->kex_ctx = dh_setup_group(ssh->kex);
51470298 5132 s->kex_init_value = SSH2_MSG_KEXDH_INIT;
5133 s->kex_reply_value = SSH2_MSG_KEXDH_REPLY;
d1aaf71d 5134 logeventf(ssh, "Using Diffie-Hellman with standard group \"%s\"",
5135 ssh->kex->groupname);
8d5de777 5136 }
e5574168 5137
a92dd380 5138 logevent("Doing Diffie-Hellman key exchange");
e5574168 5139 /*
a92dd380 5140 * Now generate and send e for Diffie-Hellman.
e5574168 5141 */
27cd7fc2 5142 s->e = dh_create_e(ssh->kex_ctx, s->nbits * 2);
ff3187f6 5143 s->pktout = ssh2_pkt_init(s->kex_init_value);
5144 ssh2_pkt_addmp(s->pktout, s->e);
590f6a5f 5145 ssh2_pkt_send_noqueue(ssh, s->pktout);
e5574168 5146
ff3187f6 5147 crWaitUntil(pktin);
5148 if (pktin->type != s->kex_reply_value) {
6b5cf8b4 5149 bombout(("expected key exchange reply packet from server"));
7ffdbc1a 5150 crStop(0);
7cca0d81 5151 }
ff3187f6 5152 ssh_pkt_getstring(pktin, &s->hostkeydata, &s->hostkeylen);
5153 s->f = ssh2_pkt_getmp(pktin);
5154 if (!s->f) {
5155 bombout(("unable to parse key exchange reply packet"));
5156 crStop(0);
5157 }
5158 ssh_pkt_getstring(pktin, &s->sigdata, &s->siglen);
e5574168 5159
27cd7fc2 5160 s->K = dh_find_K(ssh->kex_ctx, s->f);
e5574168 5161
51470298 5162 sha_string(&ssh->exhash, s->hostkeydata, s->hostkeylen);
5163 if (ssh->kex == &ssh_diffiehellman_gex) {
5164 sha_uint32(&ssh->exhash, s->pbits);
5165 sha_mpint(&ssh->exhash, s->p);
5166 sha_mpint(&ssh->exhash, s->g);
a92dd380 5167 }
51470298 5168 sha_mpint(&ssh->exhash, s->e);
5169 sha_mpint(&ssh->exhash, s->f);
5170 sha_mpint(&ssh->exhash, s->K);
5171 SHA_Final(&ssh->exhash, s->exchange_hash);
e5574168 5172
27cd7fc2 5173 dh_cleanup(ssh->kex_ctx);
fabd1805 5174 ssh->kex_ctx = NULL;
3709bfe9 5175
7cca0d81 5176#if 0
765c4200 5177 debug(("Exchange hash is:\n"));
51470298 5178 dmemdump(s->exchange_hash, 20);
7cca0d81 5179#endif
5180
51470298 5181 s->hkey = ssh->hostkey->newkey(s->hostkeydata, s->hostkeylen);
5182 if (!s->hkey ||
5183 !ssh->hostkey->verifysig(s->hkey, s->sigdata, s->siglen,
d8baa528 5184 (char *)s->exchange_hash, 20)) {
6b5cf8b4 5185 bombout(("Server's host key did not match the signature supplied"));
7ffdbc1a 5186 crStop(0);
8d5de777 5187 }
e5574168 5188
5189 /*
7cca0d81 5190 * Authenticate remote host: verify host key. (We've already
5191 * checked the signature of the exchange hash.)
e5574168 5192 */
51470298 5193 s->keystr = ssh->hostkey->fmtkey(s->hkey);
5194 s->fingerprint = ssh->hostkey->fingerprint(s->hkey);
bb348ab1 5195 sk_set_frozen(ssh->s, 1);
a8327734 5196 verify_ssh_host_key(ssh->frontend,
5197 ssh->savedhost, ssh->savedport, ssh->hostkey->keytype,
51470298 5198 s->keystr, s->fingerprint);
bb348ab1 5199 sk_set_frozen(ssh->s, 0);
e13bba36 5200 if (!s->got_session_id) { /* don't bother logging this in rekeys */
5e0d7cb8 5201 logevent("Host key fingerprint is:");
51470298 5202 logevent(s->fingerprint);
5e0d7cb8 5203 }
51470298 5204 sfree(s->fingerprint);
5205 sfree(s->keystr);
5206 ssh->hostkey->freekey(s->hkey);
d39f364a 5207
5208 /*
9442dd57 5209 * The exchange hash from the very first key exchange is also
5210 * the session id, used in session key construction and
5211 * authentication.
5212 */
e13bba36 5213 if (!s->got_session_id) {
9442dd57 5214 memcpy(ssh->v2_session_id, s->exchange_hash,
5215 sizeof(s->exchange_hash));
e13bba36 5216 s->got_session_id = TRUE;
5217 }
9442dd57 5218
5219 /*
7cca0d81 5220 * Send SSH2_MSG_NEWKEYS.
d39f364a 5221 */
ff3187f6 5222 s->pktout = ssh2_pkt_init(SSH2_MSG_NEWKEYS);
590f6a5f 5223 ssh2_pkt_send_noqueue(ssh, s->pktout);
9442dd57 5224 ssh->outgoing_data_size = 0; /* start counting from here */
5225
5226 /*
5227 * We've sent client NEWKEYS, so create and initialise
c64fe7d4 5228 * client-to-server session keys.
9442dd57 5229 */
5230 if (ssh->cs_cipher_ctx)
5231 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
5232 ssh->cscipher = s->cscipher_tobe;
5233 ssh->cs_cipher_ctx = ssh->cscipher->make_context();
5234
5235 if (ssh->cs_mac_ctx)
5236 ssh->csmac->free_context(ssh->cs_mac_ctx);
5237 ssh->csmac = s->csmac_tobe;
5238 ssh->cs_mac_ctx = ssh->csmac->make_context();
5239
5240 if (ssh->cs_comp_ctx)
5241 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
5242 ssh->cscomp = s->cscomp_tobe;
5243 ssh->cs_comp_ctx = ssh->cscomp->compress_init();
5244
5245 /*
5246 * Set IVs on client-to-server keys. Here we use the exchange
5247 * hash from the _first_ key exchange.
5248 */
5249 {
5250 unsigned char keyspace[40];
5251 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'C',keyspace);
5252 ssh->cscipher->setkey(ssh->cs_cipher_ctx, keyspace);
5253 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'A',keyspace);
5254 ssh->cscipher->setiv(ssh->cs_cipher_ctx, keyspace);
5255 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'E',keyspace);
5256 ssh->csmac->setkey(ssh->cs_mac_ctx, keyspace);
5257 }
5258
5259 logeventf(ssh, "Initialised %.200s client->server encryption",
5260 ssh->cscipher->text_name);
5261 logeventf(ssh, "Initialised %.200s client->server MAC algorithm",
5262 ssh->csmac->text_name);
5263 if (ssh->cscomp->text_name)
5264 logeventf(ssh, "Initialised %s compression",
5265 ssh->cscomp->text_name);
590f6a5f 5266
5267 /*
5268 * Now our end of the key exchange is complete, we can send all
5269 * our queued higher-layer packets.
5270 */
5271 ssh->queueing = FALSE;
5272 ssh2_pkt_queuesend(ssh);
d39f364a 5273
5274 /*
8406eaf9 5275 * Expect SSH2_MSG_NEWKEYS from server.
5276 */
ff3187f6 5277 crWaitUntil(pktin);
5278 if (pktin->type != SSH2_MSG_NEWKEYS) {
6b5cf8b4 5279 bombout(("expected new-keys packet from server"));
7ffdbc1a 5280 crStop(0);
8406eaf9 5281 }
9442dd57 5282 ssh->incoming_data_size = 0; /* start counting from here */
8406eaf9 5283
5284 /*
9442dd57 5285 * We've seen server NEWKEYS, so create and initialise
5286 * server-to-client session keys.
d39f364a 5287 */
371e569c 5288 if (ssh->sc_cipher_ctx)
5289 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
51470298 5290 ssh->sccipher = s->sccipher_tobe;
371e569c 5291 ssh->sc_cipher_ctx = ssh->sccipher->make_context();
e0e1a00d 5292
e0e1a00d 5293 if (ssh->sc_mac_ctx)
5294 ssh->scmac->free_context(ssh->sc_mac_ctx);
51470298 5295 ssh->scmac = s->scmac_tobe;
e0e1a00d 5296 ssh->sc_mac_ctx = ssh->scmac->make_context();
5297
5366aed8 5298 if (ssh->sc_comp_ctx)
5299 ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
51470298 5300 ssh->sccomp = s->sccomp_tobe;
5366aed8 5301 ssh->sc_comp_ctx = ssh->sccomp->decompress_init();
5302
d39f364a 5303 /*
9442dd57 5304 * Set IVs on server-to-client keys. Here we use the exchange
5305 * hash from the _first_ key exchange.
d39f364a 5306 */
51470298 5307 {
5308 unsigned char keyspace[40];
51470298 5309 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'D',keyspace);
371e569c 5310 ssh->sccipher->setkey(ssh->sc_cipher_ctx, keyspace);
51470298 5311 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'B',keyspace);
371e569c 5312 ssh->sccipher->setiv(ssh->sc_cipher_ctx, keyspace);
51470298 5313 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'F',keyspace);
e0e1a00d 5314 ssh->scmac->setkey(ssh->sc_mac_ctx, keyspace);
51470298 5315 }
57356d63 5316 logeventf(ssh, "Initialised %.200s server->client encryption",
5317 ssh->sccipher->text_name);
6c135243 5318 logeventf(ssh, "Initialised %.200s server->client MAC algorithm",
5319 ssh->scmac->text_name);
57356d63 5320 if (ssh->sccomp->text_name)
5321 logeventf(ssh, "Initialised %s decompression",
5322 ssh->sccomp->text_name);
9442dd57 5323
5324 /*
5325 * Free key exchange data.
5326 */
679539d7 5327 freebn(s->f);
679539d7 5328 freebn(s->K);
b3949e7e 5329 if (ssh->kex == &ssh_diffiehellman_gex) {
5330 freebn(s->g);
5331 freebn(s->p);
5332 }
d39f364a 5333
033b4cef 5334 /*
e13bba36 5335 * Key exchange is over. Loop straight back round if we have a
5336 * deferred rekey reason.
5337 */
5338 if (ssh->deferred_rekey_reason) {
5339 logevent(ssh->deferred_rekey_reason);
5340 pktin = NULL;
5341 ssh->deferred_rekey_reason = NULL;
5342 goto begin_key_exchange;
5343 }
5344
5345 /*
5346 * Otherwise, schedule a timer for our next rekey.
9442dd57 5347 */
5348 ssh->kex_in_progress = FALSE;
e6c1536e 5349 ssh->last_rekey = GETTICKCOUNT();
d57f70af 5350 if (ssh->cfg.ssh_rekey_time != 0)
5351 ssh->next_rekey = schedule_timer(ssh->cfg.ssh_rekey_time*60*TICKSPERSEC,
5352 ssh2_timer, ssh);
e13bba36 5353
9442dd57 5354 /*
0db56f73 5355 * If this is the first key exchange phase, we must pass the
5356 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
5357 * wants to see it but because it will need time to initialise
5358 * itself before it sees an actual packet. In subsequent key
5359 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
5360 * it would only confuse the layer above.
5361 */
e13bba36 5362 if (s->activated_authconn) {
b09eaa88 5363 crReturn(1);
0db56f73 5364 }
e13bba36 5365 s->activated_authconn = TRUE;
0db56f73 5366
5367 /*
7cca0d81 5368 * Now we're encrypting. Begin returning 1 to the protocol main
5369 * function so that other things can run on top of the
5370 * transport. If we ever see a KEXINIT, we must go back to the
5371 * start.
9442dd57 5372 *
5373 * We _also_ go back to the start if we see pktin==NULL and
5374 * inlen==-1, because this is a special signal meaning
5375 * `initiate client-driven rekey', and `in' contains a message
5376 * giving the reason for the rekey.
033b4cef 5377 */
9442dd57 5378 while (!((pktin && pktin->type == SSH2_MSG_KEXINIT) ||
5379 (!pktin && inlen == -1))) {
f382c87d 5380 wait_for_rekey:
32874aea 5381 crReturn(1);
e96adf72 5382 }
9442dd57 5383 if (pktin) {
5384 logevent("Server initiated key re-exchange");
5385 } else {
f382c87d 5386 /*
5387 * Special case: if the server bug is set that doesn't
5388 * allow rekeying, we give a different log message and
5389 * continue waiting. (If such a server _initiates_ a rekey,
5390 * we process it anyway!)
5391 */
5392 if ((ssh->remote_bugs & BUG_SSH2_REKEY)) {
5393 logeventf(ssh, "Server bug prevents key re-exchange (%s)",
5394 (char *)in);
5395 /* Reset the counters, so that at least this message doesn't
5396 * hit the event log _too_ often. */
5397 ssh->outgoing_data_size = 0;
5398 ssh->incoming_data_size = 0;
5399 if (ssh->cfg.ssh_rekey_time != 0) {
5400 ssh->next_rekey =
5401 schedule_timer(ssh->cfg.ssh_rekey_time*60*TICKSPERSEC,
5402 ssh2_timer, ssh);
5403 }
5404 goto wait_for_rekey; /* this is utterly horrid */
5405 } else {
5406 logeventf(ssh, "Initiating key re-exchange (%s)", (char *)in);
f382c87d 5407 }
9442dd57 5408 }
7cca0d81 5409 goto begin_key_exchange;
e5574168 5410
5411 crFinish(1);
5412}
5413
7cca0d81 5414/*
783415f8 5415 * Add data to an SSH2 channel output buffer.
5416 */
32874aea 5417static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
5418 int len)
5419{
5471d09a 5420 bufchain_add(&c->v.v2.outbuffer, buf, len);
783415f8 5421}
5422
5423/*
5424 * Attempt to send data on an SSH2 channel.
5425 */
5471d09a 5426static int ssh2_try_send(struct ssh_channel *c)
32874aea 5427{
51470298 5428 Ssh ssh = c->ssh;
ff3187f6 5429 struct Packet *pktout;
51470298 5430
5471d09a 5431 while (c->v.v2.remwindow > 0 && bufchain_size(&c->v.v2.outbuffer) > 0) {
5432 int len;
5433 void *data;
5434 bufchain_prefix(&c->v.v2.outbuffer, &data, &len);
5435 if ((unsigned)len > c->v.v2.remwindow)
5436 len = c->v.v2.remwindow;
5437 if ((unsigned)len > c->v.v2.remmaxpkt)
5438 len = c->v.v2.remmaxpkt;
ff3187f6 5439 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
5440 ssh2_pkt_adduint32(pktout, c->remoteid);
5441 dont_log_data(ssh, pktout, PKTLOG_OMIT);
5442 ssh2_pkt_addstring_start(pktout);
5443 ssh2_pkt_addstring_data(pktout, data, len);
5444 end_log_omission(ssh, pktout);
5445 ssh2_pkt_send(ssh, pktout);
5471d09a 5446 bufchain_consume(&c->v.v2.outbuffer, len);
5447 c->v.v2.remwindow -= len;
5448 }
5449
5450 /*
5451 * After having sent as much data as we can, return the amount
5452 * still buffered.
5453 */
5454 return bufchain_size(&c->v.v2.outbuffer);
5455}
5456
5457/*
5458 * Potentially enlarge the window on an SSH2 channel.
5459 */
5460static void ssh2_set_window(struct ssh_channel *c, unsigned newwin)
5461{
51470298 5462 Ssh ssh = c->ssh;
5463
6b69f42e 5464 /*
5465 * Never send WINDOW_ADJUST for a channel that the remote side
5466 * already thinks it's closed; there's no point, since it won't
5467 * be sending any more data anyway.
5468 */
5469 if (c->closes != 0)
5470 return;
5471
d252310a 5472 /*
5473 * Only send a WINDOW_ADJUST if there's significantly more window
5474 * available than the other end thinks there is. This saves us
5475 * sending a WINDOW_ADJUST for every character in a shell session.
5476 *
5477 * "Significant" is arbitrarily defined as half the window size.
5478 */
5479 if (newwin > c->v.v2.locwindow * 2) {
ff3187f6 5480 struct Packet *pktout;
5481
5482 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
5483 ssh2_pkt_adduint32(pktout, c->remoteid);
5484 ssh2_pkt_adduint32(pktout, newwin - c->v.v2.locwindow);
5485 ssh2_pkt_send(ssh, pktout);
5471d09a 5486 c->v.v2.locwindow = newwin;
783415f8 5487 }
5488}
5489
51df0ab5 5490static void ssh2_msg_channel_window_adjust(Ssh ssh, struct Packet *pktin)
b09eaa88 5491{
5492 unsigned i = ssh_pkt_getuint32(pktin);
5493 struct ssh_channel *c;
5494 c = find234(ssh->channels, &i, ssh_channelfind);
5495 if (c && !c->closes)
5496 c->v.v2.remwindow += ssh_pkt_getuint32(pktin);
5497}
5498
51df0ab5 5499static void ssh2_msg_channel_data(Ssh ssh, struct Packet *pktin)
5500{
5501 char *data;
6d44acc9 5502 int length;
51df0ab5 5503 unsigned i = ssh_pkt_getuint32(pktin);
5504 struct ssh_channel *c;
5505 c = find234(ssh->channels, &i, ssh_channelfind);
5506 if (!c)
5507 return; /* nonexistent channel */
5508 if (pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
5509 ssh_pkt_getuint32(pktin) != SSH2_EXTENDED_DATA_STDERR)
5510 return; /* extended but not stderr */
5511 ssh_pkt_getstring(pktin, &data, &length);
5512 if (data) {
5513 int bufsize = 0;
5514 c->v.v2.locwindow -= length;
5515 switch (c->type) {
5516 case CHAN_MAINSESSION:
5517 bufsize =
5518 from_backend(ssh->frontend, pktin->type ==
5519 SSH2_MSG_CHANNEL_EXTENDED_DATA,
5520 data, length);
5521 break;
5522 case CHAN_X11:
5523 bufsize = x11_send(c->u.x11.s, data, length);
5524 break;
5525 case CHAN_SOCKDATA:
5526 bufsize = pfd_send(c->u.pfd.s, data, length);
5527 break;
5528 case CHAN_AGENT:
5529 while (length > 0) {
5530 if (c->u.a.lensofar < 4) {
aa63ab7e 5531 unsigned int l = min(4 - c->u.a.lensofar, length);
51df0ab5 5532 memcpy(c->u.a.msglen + c->u.a.lensofar,
5533 data, l);
5534 data += l;
5535 length -= l;
5536 c->u.a.lensofar += l;
5537 }
5538 if (c->u.a.lensofar == 4) {
5539 c->u.a.totallen =
5540 4 + GET_32BIT(c->u.a.msglen);
5541 c->u.a.message = snewn(c->u.a.totallen,
5542 unsigned char);
5543 memcpy(c->u.a.message, c->u.a.msglen, 4);
5544 }
5545 if (c->u.a.lensofar >= 4 && length > 0) {
aa63ab7e 5546 unsigned int l =
51df0ab5 5547 min(c->u.a.totallen - c->u.a.lensofar,
5548 length);
5549 memcpy(c->u.a.message + c->u.a.lensofar,
5550 data, l);
5551 data += l;
5552 length -= l;
5553 c->u.a.lensofar += l;
5554 }
5555 if (c->u.a.lensofar == c->u.a.totallen) {
5556 void *reply;
5557 int replylen;
5558 if (agent_query(c->u.a.message,
5559 c->u.a.totallen,
5560 &reply, &replylen,
5561 ssh_agentf_callback, c))
5562 ssh_agentf_callback(c, reply, replylen);
5563 sfree(c->u.a.message);
5564 c->u.a.lensofar = 0;
5565 }
5566 }
5567 bufsize = 0;
5568 break;
5569 }
5570 /*
5571 * If we are not buffering too much data,
5572 * enlarge the window again at the remote side.
5573 */
5574 if (bufsize < OUR_V2_WINSIZE)
5575 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
5576 }
5577}
5578
5579static void ssh2_msg_channel_eof(Ssh ssh, struct Packet *pktin)
5580{
5581 unsigned i = ssh_pkt_getuint32(pktin);
5582 struct ssh_channel *c;
5583
5584 c = find234(ssh->channels, &i, ssh_channelfind);
5585 if (!c)
5586 return; /* nonexistent channel */
5587
5588 if (c->type == CHAN_X11) {
5589 /*
5590 * Remote EOF on an X11 channel means we should
5591 * wrap up and close the channel ourselves.
5592 */
5593 x11_close(c->u.x11.s);
5594 sshfwd_close(c);
5595 } else if (c->type == CHAN_AGENT) {
5596 sshfwd_close(c);
5597 } else if (c->type == CHAN_SOCKDATA) {
5598 pfd_close(c->u.pfd.s);
5599 sshfwd_close(c);
5600 }
5601}
5602
5603static void ssh2_msg_channel_close(Ssh ssh, struct Packet *pktin)
5604{
5605 unsigned i = ssh_pkt_getuint32(pktin);
5606 struct ssh_channel *c;
5607 struct Packet *pktout;
5608
5609 c = find234(ssh->channels, &i, ssh_channelfind);
64d6ff88 5610 if (!c || c->halfopen) {
51df0ab5 5611 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5612 c ? "half-open" : "nonexistent", i));
5613 return;
5614 }
5615 /* Do pre-close processing on the channel. */
5616 switch (c->type) {
5617 case CHAN_MAINSESSION:
5618 ssh->mainchan = NULL;
5619 update_specials_menu(ssh->frontend);
5620 break;
5621 case CHAN_X11:
5622 if (c->u.x11.s != NULL)
5623 x11_close(c->u.x11.s);
5624 sshfwd_close(c);
5625 break;
5626 case CHAN_AGENT:
5627 sshfwd_close(c);
5628 break;
5629 case CHAN_SOCKDATA:
5630 if (c->u.pfd.s != NULL)
5631 pfd_close(c->u.pfd.s);
5632 sshfwd_close(c);
5633 break;
5634 }
5635 if (c->closes == 0) {
5636 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
5637 ssh2_pkt_adduint32(pktout, c->remoteid);
5638 ssh2_pkt_send(ssh, pktout);
5639 }
5640 del234(ssh->channels, c);
5641 bufchain_clear(&c->v.v2.outbuffer);
5642 sfree(c);
5643
5644 /*
5645 * See if that was the last channel left open.
5646 * (This is only our termination condition if we're
5647 * not running in -N mode.)
5648 */
5649 if (!ssh->cfg.ssh_no_shell && count234(ssh->channels) == 0) {
5650 logevent("All channels closed. Disconnecting");
5651#if 0
5652 /*
5653 * We used to send SSH_MSG_DISCONNECT here,
5654 * because I'd believed that _every_ conforming
5655 * SSH2 connection had to end with a disconnect
5656 * being sent by at least one side; apparently
5657 * I was wrong and it's perfectly OK to
5658 * unceremoniously slam the connection shut
5659 * when you're done, and indeed OpenSSH feels
5660 * this is more polite than sending a
5661 * DISCONNECT. So now we don't.
5662 */
5663 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
5664 ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
5665 ssh2_pkt_addstring(s->pktout, "All open channels closed");
5666 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
5667 ssh2_pkt_send_noqueue(ssh, s->pktout);
5668#endif
ac934965 5669 ssh->close_expected = TRUE;
51df0ab5 5670 ssh_closing((Plug)ssh, NULL, 0, 0);
5671 }
5672}
5673
5674static void ssh2_msg_channel_open_confirmation(Ssh ssh, struct Packet *pktin)
5675{
5676 unsigned i = ssh_pkt_getuint32(pktin);
5677 struct ssh_channel *c;
5678 struct Packet *pktout;
5679
5680 c = find234(ssh->channels, &i, ssh_channelfind);
5681 if (!c)
5682 return; /* nonexistent channel */
5683 if (c->type != CHAN_SOCKDATA_DORMANT)
5684 return; /* dunno why they're confirming this */
5685 c->remoteid = ssh_pkt_getuint32(pktin);
64d6ff88 5686 c->halfopen = FALSE;
51df0ab5 5687 c->type = CHAN_SOCKDATA;
5688 c->v.v2.remwindow = ssh_pkt_getuint32(pktin);
5689 c->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin);
5690 if (c->u.pfd.s)
5691 pfd_confirm(c->u.pfd.s);
5692 if (c->closes) {
5693 /*
5694 * We have a pending close on this channel,
5695 * which we decided on before the server acked
5696 * the channel open. So now we know the
5697 * remoteid, we can close it again.
5698 */
5699 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
5700 ssh2_pkt_adduint32(pktout, c->remoteid);
5701 ssh2_pkt_send(ssh, pktout);
5702 }
5703}
5704
5705static void ssh2_msg_channel_open_failure(Ssh ssh, struct Packet *pktin)
5706{
5707 static const char *const reasons[] = {
5708 "<unknown reason code>",
5709 "Administratively prohibited",
5710 "Connect failed",
5711 "Unknown channel type",
5712 "Resource shortage",
5713 };
5714 unsigned i = ssh_pkt_getuint32(pktin);
5715 unsigned reason_code;
5716 char *reason_string;
5717 int reason_length;
51df0ab5 5718 struct ssh_channel *c;
5719 c = find234(ssh->channels, &i, ssh_channelfind);
5720 if (!c)
5721 return; /* nonexistent channel */
5722 if (c->type != CHAN_SOCKDATA_DORMANT)
5723 return; /* dunno why they're failing this */
5724
5725 reason_code = ssh_pkt_getuint32(pktin);
5726 if (reason_code >= lenof(reasons))
5727 reason_code = 0; /* ensure reasons[reason_code] in range */
5728 ssh_pkt_getstring(pktin, &reason_string, &reason_length);
fb983202 5729 logeventf(ssh, "Forwarded connection refused by server: %s [%.*s]",
5730 reasons[reason_code], reason_length, reason_string);
51df0ab5 5731
5732 pfd_close(c->u.pfd.s);
5733
5734 del234(ssh->channels, c);
5735 sfree(c);
5736}
5737
5738static void ssh2_msg_channel_request(Ssh ssh, struct Packet *pktin)
5739{
5740 unsigned localid;
5741 char *type;
5742 int typelen, want_reply;
5743 int reply = SSH2_MSG_CHANNEL_FAILURE; /* default */
5744 struct ssh_channel *c;
5745 struct Packet *pktout;
5746
5747 localid = ssh_pkt_getuint32(pktin);
5748 ssh_pkt_getstring(pktin, &type, &typelen);
5749 want_reply = ssh2_pkt_getbool(pktin);
5750
5751 /*
5752 * First, check that the channel exists. Otherwise,
5753 * we can instantly disconnect with a rude message.
5754 */
5755 c = find234(ssh->channels, &localid, ssh_channelfind);
5756 if (!c) {
5757 char buf[80];
5758 sprintf(buf, "Received channel request for nonexistent"
5759 " channel %d", localid);
5760 logevent(buf);
5761 pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
5762 ssh2_pkt_adduint32(pktout, SSH2_DISCONNECT_BY_APPLICATION);
5763 ssh2_pkt_addstring(pktout, buf);
5764 ssh2_pkt_addstring(pktout, "en"); /* language tag */
5765 ssh2_pkt_send_noqueue(ssh, pktout);
5766 connection_fatal(ssh->frontend, "%s", buf);
ac934965 5767 ssh->close_expected = TRUE;
51df0ab5 5768 ssh_closing((Plug)ssh, NULL, 0, 0);
5769 return;
5770 }
5771
5772 /*
5773 * Having got the channel number, we now look at
5774 * the request type string to see if it's something
5775 * we recognise.
5776 */
5777 if (c == ssh->mainchan) {
5778 /*
5779 * We recognise "exit-status" and "exit-signal" on
5780 * the primary channel.
5781 */
5782 if (typelen == 11 &&
5783 !memcmp(type, "exit-status", 11)) {
5784
5785 ssh->exitcode = ssh_pkt_getuint32(pktin);
5786 logeventf(ssh, "Server sent command exit status %d",
5787 ssh->exitcode);
5788 reply = SSH2_MSG_CHANNEL_SUCCESS;
5789
5790 } else if (typelen == 11 &&
5791 !memcmp(type, "exit-signal", 11)) {
5792
5793 int is_plausible = TRUE, is_int = FALSE;
5794 char *fmt_sig = "", *fmt_msg = "";
5795 char *msg;
5796 int msglen = 0, core = FALSE;
5797 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
5798 * provide an `int' for the signal, despite its
5799 * having been a `string' in the drafts since at
5800 * least 2001. (Fixed in session.c 1.147.) Try to
5801 * infer which we can safely parse it as. */
5802 {
5803 unsigned char *p = pktin->body +
5804 pktin->savedpos;
5805 long len = pktin->length - pktin->savedpos;
5806 unsigned long num = GET_32BIT(p); /* what is it? */
5807 /* If it's 0, it hardly matters; assume string */
5808 if (num == 0) {
5809 is_int = FALSE;
5810 } else {
5811 int maybe_int = FALSE, maybe_str = FALSE;
5812#define CHECK_HYPOTHESIS(offset, result) \
5813 do { \
5814 long q = offset; \
5815 if (q >= 0 && q+4 <= len) { \
5816 q = q + 4 + GET_32BIT(p+q); \
5817 if (q >= 0 && q+4 <= len && \
c849ff23 5818 ((q = q + 4 + GET_32BIT(p+q))!= 0) && q == len) \
51df0ab5 5819 result = TRUE; \
5820 } \
5821 } while(0)
5822 CHECK_HYPOTHESIS(4+1, maybe_int);
5823 CHECK_HYPOTHESIS(4+num+1, maybe_str);
5824#undef CHECK_HYPOTHESIS
5825 if (maybe_int && !maybe_str)
5826 is_int = TRUE;
5827 else if (!maybe_int && maybe_str)
5828 is_int = FALSE;
5829 else
5830 /* Crikey. Either or neither. Panic. */
5831 is_plausible = FALSE;
5832 }
5833 }
5834 if (is_plausible) {
5835 if (is_int) {
5836 /* Old non-standard OpenSSH. */
5837 int signum = ssh_pkt_getuint32(pktin);
5838 fmt_sig = dupprintf(" %d", signum);
5839 } else {
5840 /* As per the drafts. */
5841 char *sig;
5842 int siglen;
5843 ssh_pkt_getstring(pktin, &sig, &siglen);
5844 /* Signal name isn't supposed to be blank, but
5845 * let's cope gracefully if it is. */
5846 if (siglen) {
5847 fmt_sig = dupprintf(" \"%.*s\"",
5848 siglen, sig);
5849 }
5850 }
5851 core = ssh2_pkt_getbool(pktin);
5852 ssh_pkt_getstring(pktin, &msg, &msglen);
5853 if (msglen) {
5854 fmt_msg = dupprintf(" (\"%.*s\")", msglen, msg);
5855 }
5856 /* ignore lang tag */
5857 } /* else don't attempt to parse */
5858 logeventf(ssh, "Server exited on signal%s%s%s",
5859 fmt_sig, core ? " (core dumped)" : "",
5860 fmt_msg);
5861 if (*fmt_sig) sfree(fmt_sig);
5862 if (*fmt_msg) sfree(fmt_msg);
5863 reply = SSH2_MSG_CHANNEL_SUCCESS;
5864
5865 }
5866 } else {
5867 /*
5868 * This is a channel request we don't know
5869 * about, so we now either ignore the request
5870 * or respond with CHANNEL_FAILURE, depending
5871 * on want_reply.
5872 */
5873 reply = SSH2_MSG_CHANNEL_FAILURE;
5874 }
5875 if (want_reply) {
5876 pktout = ssh2_pkt_init(reply);
5877 ssh2_pkt_adduint32(pktout, c->remoteid);
5878 ssh2_pkt_send(ssh, pktout);
5879 }
5880}
5881
5882static void ssh2_msg_global_request(Ssh ssh, struct Packet *pktin)
5883{
5884 char *type;
5885 int typelen, want_reply;
5886 struct Packet *pktout;
5887
5888 ssh_pkt_getstring(pktin, &type, &typelen);
5889 want_reply = ssh2_pkt_getbool(pktin);
5890
5891 /*
5892 * We currently don't support any global requests
5893 * at all, so we either ignore the request or
5894 * respond with REQUEST_FAILURE, depending on
5895 * want_reply.
5896 */
5897 if (want_reply) {
5898 pktout = ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE);
5899 ssh2_pkt_send(ssh, pktout);
5900 }
5901}
5902
5903static void ssh2_msg_channel_open(Ssh ssh, struct Packet *pktin)
5904{
5905 char *type;
5906 int typelen;
5907 char *peeraddr;
5908 int peeraddrlen;
5909 int peerport;
5910 char *error = NULL;
5911 struct ssh_channel *c;
5912 unsigned remid, winsize, pktsize;
5913 struct Packet *pktout;
5914
5915 ssh_pkt_getstring(pktin, &type, &typelen);
5916 c = snew(struct ssh_channel);
5917 c->ssh = ssh;
5918
5919 remid = ssh_pkt_getuint32(pktin);
5920 winsize = ssh_pkt_getuint32(pktin);
5921 pktsize = ssh_pkt_getuint32(pktin);
5922
5923 if (typelen == 3 && !memcmp(type, "x11", 3)) {
5924 char *addrstr;
5925
5926 ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
5927 addrstr = snewn(peeraddrlen+1, char);
5928 memcpy(addrstr, peeraddr, peeraddrlen);
5929 addrstr[peeraddrlen] = '\0';
5930 peerport = ssh_pkt_getuint32(pktin);
5931
5932 logeventf(ssh, "Received X11 connect request from %s:%d",
5933 addrstr, peerport);
5934
5935 if (!ssh->X11_fwd_enabled)
5936 error = "X11 forwarding is not enabled";
5937 else if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
5938 ssh->x11auth, addrstr, peerport,
5939 &ssh->cfg) != NULL) {
5940 error = "Unable to open an X11 connection";
5941 } else {
5942 logevent("Opening X11 forward connection succeeded");
5943 c->type = CHAN_X11;
5944 }
5945
5946 sfree(addrstr);
5947 } else if (typelen == 15 &&
5948 !memcmp(type, "forwarded-tcpip", 15)) {
5949 struct ssh_rportfwd pf, *realpf;
5950 char *dummy;
5951 int dummylen;
5952 ssh_pkt_getstring(pktin, &dummy, &dummylen);/* skip address */
5953 pf.sport = ssh_pkt_getuint32(pktin);
5954 ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
5955 peerport = ssh_pkt_getuint32(pktin);
5956 realpf = find234(ssh->rportfwds, &pf, NULL);
5957 logeventf(ssh, "Received remote port %d open request "
5958 "from %s:%d", pf.sport, peeraddr, peerport);
5959 if (realpf == NULL) {
5960 error = "Remote port is not recognised";
5961 } else {
5962 const char *e = pfd_newconnect(&c->u.pfd.s,
5963 realpf->dhost,
5964 realpf->dport, c,
05581745 5965 &ssh->cfg,
5966 realpf->pfrec->addressfamily);
51df0ab5 5967 logeventf(ssh, "Attempting to forward remote port to "
5968 "%s:%d", realpf->dhost, realpf->dport);
5969 if (e != NULL) {
5970 logeventf(ssh, "Port open failed: %s", e);
5971 error = "Port open failed";
5972 } else {
5973 logevent("Forwarded port opened successfully");
5974 c->type = CHAN_SOCKDATA;
5975 }
5976 }
5977 } else if (typelen == 22 &&
5978 !memcmp(type, "auth-agent@openssh.com", 3)) {
5979 if (!ssh->agentfwd_enabled)
5980 error = "Agent forwarding is not enabled";
5981 else {
5982 c->type = CHAN_AGENT; /* identify channel type */
5983 c->u.a.lensofar = 0;
5984 }
5985 } else {
5986 error = "Unsupported channel type requested";
5987 }
5988
5989 c->remoteid = remid;
64d6ff88 5990 c->halfopen = FALSE;
51df0ab5 5991 if (error) {
5992 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE);
5993 ssh2_pkt_adduint32(pktout, c->remoteid);
5994 ssh2_pkt_adduint32(pktout, SSH2_OPEN_CONNECT_FAILED);
5995 ssh2_pkt_addstring(pktout, error);
5996 ssh2_pkt_addstring(pktout, "en"); /* language tag */
5997 ssh2_pkt_send(ssh, pktout);
5998 logeventf(ssh, "Rejected channel open: %s", error);
5999 sfree(c);
6000 } else {
6001 c->localid = alloc_channel_id(ssh);
6002 c->closes = 0;
6003 c->v.v2.locwindow = OUR_V2_WINSIZE;
6004 c->v.v2.remwindow = winsize;
6005 c->v.v2.remmaxpkt = pktsize;
6006 bufchain_init(&c->v.v2.outbuffer);
6007 add234(ssh->channels, c);
6008 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
6009 ssh2_pkt_adduint32(pktout, c->remoteid);
6010 ssh2_pkt_adduint32(pktout, c->localid);
6011 ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);
954d5c5a 6012 ssh2_pkt_adduint32(pktout, OUR_V2_MAXPKT); /* our max pkt size */
51df0ab5 6013 ssh2_pkt_send(ssh, pktout);
6014 }
6015}
6016
783415f8 6017/*
7cca0d81 6018 * Handle the SSH2 userauth and connection layers.
6019 */
ff3187f6 6020static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
6021 struct Packet *pktin)
7cca0d81 6022{
51470298 6023 struct do_ssh2_authconn_state {
6024 enum {
6025 AUTH_INVALID, AUTH_PUBLICKEY_AGENT, AUTH_PUBLICKEY_FILE,
6026 AUTH_PASSWORD,
6027 AUTH_KEYBOARD_INTERACTIVE
6028 } method;
6029 enum {
6030 AUTH_TYPE_NONE,
6031 AUTH_TYPE_PUBLICKEY,
6032 AUTH_TYPE_PUBLICKEY_OFFER_LOUD,
6033 AUTH_TYPE_PUBLICKEY_OFFER_QUIET,
6034 AUTH_TYPE_PASSWORD,
6035 AUTH_TYPE_KEYBOARD_INTERACTIVE,
6036 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
6037 } type;
6038 int gotit, need_pw, can_pubkey, can_passwd, can_keyb_inter;
6ac3a551 6039 int tried_pubkey_config, tried_agent;
6040 int kbd_inter_running, kbd_inter_refused;
51470298 6041 int we_are_in;
6042 int num_prompts, curr_prompt, echo;
6043 char username[100];
6044 int got_username;
85fdbe25 6045 char pwprompt[512];
51470298 6046 char password[100];
6047 void *publickey_blob;
6048 int publickey_bloblen;
6049 unsigned char request[5], *response, *p;
6050 int responselen;
6051 int keyi, nkeys;
6052 int authed;
6053 char *pkblob, *alg, *commentp;
6054 int pklen, alglen, commentlen;
6055 int siglen, retlen, len;
6056 char *q, *agentreq, *ret;
6057 int try_send;
73feed4f 6058 int num_env, env_left, env_ok;
ff3187f6 6059 struct Packet *pktout;
51470298 6060 };
6061 crState(do_ssh2_authconn_state);
6062
6063 crBegin(ssh->do_ssh2_authconn_crstate);
e5574168 6064
7cca0d81 6065 /*
6066 * Request userauth protocol, and await a response to it.
6067 */
ff3187f6 6068 s->pktout = ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
6069 ssh2_pkt_addstring(s->pktout, "ssh-userauth");
6070 ssh2_pkt_send(ssh, s->pktout);
6071 crWaitUntilV(pktin);
6072 if (pktin->type != SSH2_MSG_SERVICE_ACCEPT) {
6b5cf8b4 6073 bombout(("Server refused user authentication protocol"));
7ffdbc1a 6074 crStopV;
8d5de777 6075 }
7cca0d81 6076
6077 /*
1408a877 6078 * We repeat this whole loop, including the username prompt,
6079 * until we manage a successful authentication. If the user
51470298 6080 * types the wrong _password_, they can be sent back to the
6081 * beginning to try another username, if this is configured on.
6082 * (If they specify a username in the config, they are never
6083 * asked, even if they do give a wrong password.)
1408a877 6084 *
6085 * I think this best serves the needs of
6086 *
6087 * - the people who have no configuration, no keys, and just
6088 * want to try repeated (username,password) pairs until they
6089 * type both correctly
6090 *
6091 * - people who have keys and configuration but occasionally
6092 * need to fall back to passwords
6093 *
6094 * - people with a key held in Pageant, who might not have
6095 * logged in to a particular machine before; so they want to
6096 * type a username, and then _either_ their key will be
6097 * accepted, _or_ they will type a password. If they mistype
6098 * the username they will want to be able to get back and
6099 * retype it!
7cca0d81 6100 */
51470298 6101 s->username[0] = '\0';
6102 s->got_username = FALSE;
1408a877 6103 do {
1408a877 6104 /*
6105 * Get a username.
6106 */
86916870 6107 if (s->got_username && !ssh->cfg.change_username) {
5bb641e1 6108 /*
6109 * We got a username last time round this loop, and
6110 * with change_username turned off we don't try to get
6111 * it again.
6112 */
aa09f7d0 6113 } else if (!*ssh->cfg.username) {
c0a81592 6114 if (ssh_get_line && !ssh_getline_pw_only) {
32874aea 6115 if (!ssh_get_line("login as: ",
51470298 6116 s->username, sizeof(s->username), FALSE)) {
32874aea 6117 /*
6118 * get_line failed to get a username.
6119 * Terminate.
6120 */
6121 logevent("No username provided. Abandoning session.");
ac934965 6122 ssh->close_expected = TRUE;
3bb2f322 6123 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 6124 crStopV;
32874aea 6125 }
6126 } else {
51470298 6127 int ret; /* need not be saved across crReturn */
6128 c_write_str(ssh, "login as: ");
6129 ssh->send_ok = 1;
6130 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
0405e71f 6131 do {
ff3187f6 6132 crWaitUntilV(!pktin);
51470298 6133 ret = process_userpass_input(ssh, in, inlen);
0405e71f 6134 } while (ret == 0);
6135 if (ret < 0)
6136 cleanup_exit(0);
4ca0c9d1 6137 c_write_str(ssh, "\r\n");
32874aea 6138 }
51470298 6139 s->username[strcspn(s->username, "\n\r")] = '\0';
7cca0d81 6140 } else {
57356d63 6141 char *stuff;
86916870 6142 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
51470298 6143 s->username[sizeof(s->username)-1] = '\0';
65a22376 6144 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
57356d63 6145 stuff = dupprintf("Using username \"%s\".\r\n", s->username);
51470298 6146 c_write_str(ssh, stuff);
57356d63 6147 sfree(stuff);
7cca0d81 6148 }
6149 }
51470298 6150 s->got_username = TRUE;
7cca0d81 6151
65a22376 6152 /*
1408a877 6153 * Send an authentication request using method "none": (a)
6154 * just in case it succeeds, and (b) so that we know what
6155 * authentication methods we can usefully try next.
65a22376 6156 */
51470298 6157 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6158
ff3187f6 6159 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6160 ssh2_pkt_addstring(s->pktout, s->username);
6161 ssh2_pkt_addstring(s->pktout, "ssh-connection");/* service requested */
6162 ssh2_pkt_addstring(s->pktout, "none"); /* method */
6163 ssh2_pkt_send(ssh, s->pktout);
51470298 6164 s->type = AUTH_TYPE_NONE;
6165 s->gotit = FALSE;
6166 s->we_are_in = FALSE;
6167
6168 s->tried_pubkey_config = FALSE;
6169 s->tried_agent = FALSE;
51470298 6170 s->kbd_inter_running = FALSE;
6ac3a551 6171 s->kbd_inter_refused = FALSE;
86916870 6172 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
9a30e26b 6173 if (!filename_is_null(ssh->cfg.keyfile)) {
231ee168 6174 int keytype;
6c6d9ed9 6175 logeventf(ssh, "Reading private key file \"%.150s\"",
6176 filename_to_str(&ssh->cfg.keyfile));
9a30e26b 6177 keytype = key_type(&ssh->cfg.keyfile);
51470298 6178 if (keytype == SSH_KEYTYPE_SSH2) {
6179 s->publickey_blob =
9a30e26b 6180 ssh2_userkey_loadpub(&ssh->cfg.keyfile, NULL,
222d54dc 6181 &s->publickey_bloblen, NULL);
51470298 6182 } else {
57356d63 6183 char *msgbuf;
c2ad7d0d 6184 logeventf(ssh, "Unable to use this key file (%s)",
a8327734 6185 key_type_to_str(keytype));
57356d63 6186 msgbuf = dupprintf("Unable to use key file \"%.150s\""
6c6d9ed9 6187 " (%s)\r\n",
6188 filename_to_str(&ssh->cfg.keyfile),
57356d63 6189 key_type_to_str(keytype));
51470298 6190 c_write_str(ssh, msgbuf);
57356d63 6191 sfree(msgbuf);
51470298 6192 s->publickey_blob = NULL;
231ee168 6193 }
396778f1 6194 } else
51470298 6195 s->publickey_blob = NULL;
65a22376 6196
1408a877 6197 while (1) {
6198 /*
6199 * Wait for the result of the last authentication request.
6200 */
51470298 6201 if (!s->gotit)
ff3187f6 6202 crWaitUntilV(pktin);
6203 while (pktin->type == SSH2_MSG_USERAUTH_BANNER) {
32874aea 6204 char *banner;
6205 int size;
6206 /*
6207 * Don't show the banner if we're operating in
6208 * non-verbose non-interactive mode. (It's probably
6209 * a script, which means nobody will read the
6210 * banner _anyway_, and moreover the printing of
6211 * the banner will screw up processing on the
6212 * output of (say) plink.)
6213 */
6214 if (flags & (FLAG_VERBOSE | FLAG_INTERACTIVE)) {
ff3187f6 6215 ssh_pkt_getstring(pktin, &banner, &size);
32874aea 6216 if (banner)
51470298 6217 c_write_untrusted(ssh, banner, size);
32874aea 6218 }
ff3187f6 6219 crWaitUntilV(pktin);
1408a877 6220 }
ff3187f6 6221 if (pktin->type == SSH2_MSG_USERAUTH_SUCCESS) {
1408a877 6222 logevent("Access granted");
51470298 6223 s->we_are_in = TRUE;
1408a877 6224 break;
6225 }
65a22376 6226
51470298 6227 if (s->kbd_inter_running &&
ff3187f6 6228 pktin->type == SSH2_MSG_USERAUTH_INFO_REQUEST) {
b3186d64 6229 /*
45068b27 6230 * This is either a further set-of-prompts packet
6231 * in keyboard-interactive authentication, or it's
6232 * the same one and we came back here with `gotit'
6233 * set. In the former case, we must reset the
6234 * curr_prompt variable.
b3186d64 6235 */
51470298 6236 if (!s->gotit)
6237 s->curr_prompt = 0;
4c6e53e3 6238 } else if (pktin->type == SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ) {
6239 /* FIXME: perhaps we should support this? */
6240 bombout(("PASSWD_CHANGEREQ not yet supported"));
6241 crStopV;
ff3187f6 6242 } else if (pktin->type != SSH2_MSG_USERAUTH_FAILURE) {
6b5cf8b4 6243 bombout(("Strange packet received during authentication: type %d",
ff3187f6 6244 pktin->type));
7ffdbc1a 6245 crStopV;
65a22376 6246 }
6247
51470298 6248 s->gotit = FALSE;
65a22376 6249
1408a877 6250 /*
6251 * OK, we're now sitting on a USERAUTH_FAILURE message, so
6252 * we can look at the string in it and know what we can
6253 * helpfully try next.
6254 */
ff3187f6 6255 if (pktin->type == SSH2_MSG_USERAUTH_FAILURE) {
1408a877 6256 char *methods;
6257 int methlen;
ff3187f6 6258 ssh_pkt_getstring(pktin, &methods, &methlen);
51470298 6259 s->kbd_inter_running = FALSE;
ff3187f6 6260 if (!ssh2_pkt_getbool(pktin)) {
1408a877 6261 /*
6262 * We have received an unequivocal Access
6263 * Denied. This can translate to a variety of
6264 * messages:
6265 *
6266 * - if we'd just tried "none" authentication,
6267 * it's not worth printing anything at all
6268 *
6269 * - if we'd just tried a public key _offer_,
6270 * the message should be "Server refused our
6271 * key" (or no message at all if the key
6272 * came from Pageant)
6273 *
6274 * - if we'd just tried anything else, the
6275 * message really should be "Access denied".
6276 *
6277 * Additionally, if we'd just tried password
6278 * authentication, we should break out of this
6279 * whole loop so as to go back to the username
91f57d1f 6280 * prompt (iff we're configured to allow
6281 * username change attempts).
1408a877 6282 */
51470298 6283 if (s->type == AUTH_TYPE_NONE) {
1408a877 6284 /* do nothing */
51470298 6285 } else if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD ||
6286 s->type == AUTH_TYPE_PUBLICKEY_OFFER_QUIET) {
6287 if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD)
6288 c_write_str(ssh, "Server refused our key\r\n");
1408a877 6289 logevent("Server refused public key");
51470298 6290 } else if (s->type==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET) {
4bdf7c46 6291 /* server declined keyboard-interactive; ignore */
1408a877 6292 } else {
51470298 6293 c_write_str(ssh, "Access denied\r\n");
1408a877 6294 logevent("Access denied");
91f57d1f 6295 if (s->type == AUTH_TYPE_PASSWORD &&
6296 ssh->cfg.change_username) {
6c9dce7c 6297 /* XXX perhaps we should allow
6298 * keyboard-interactive to do this too? */
51470298 6299 s->we_are_in = FALSE;
1408a877 6300 break;
6301 }
6302 }
6303 } else {
51470298 6304 c_write_str(ssh, "Further authentication required\r\n");
1408a877 6305 logevent("Further authentication required");
6306 }
65a22376 6307
51470298 6308 s->can_pubkey =
32874aea 6309 in_commasep_string("publickey", methods, methlen);
51470298 6310 s->can_passwd =
32874aea 6311 in_commasep_string("password", methods, methlen);
86916870 6312 s->can_keyb_inter = ssh->cfg.try_ki_auth &&
761187b6 6313 in_commasep_string("keyboard-interactive", methods, methlen);
1408a877 6314 }
65a22376 6315
51470298 6316 s->method = 0;
6317 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
954a9540 6318 s->need_pw = FALSE;
65a22376 6319
0405e71f 6320 /*
6321 * Most password/passphrase prompts will be
6322 * non-echoing, so we set this to 0 by default.
6323 * Exception is that some keyboard-interactive prompts
6324 * can be echoing, in which case we'll set this to 1.
6325 */
51470298 6326 s->echo = 0;
0405e71f 6327
51470298 6328 if (!s->method && s->can_pubkey &&
6329 agent_exists() && !s->tried_agent) {
1983e559 6330 /*
6331 * Attempt public-key authentication using Pageant.
6332 */
1983e559 6333 void *r;
51470298 6334 s->authed = FALSE;
1983e559 6335
51470298 6336 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6337 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
00db133f 6338
51470298 6339 s->tried_agent = TRUE;
1983e559 6340
6341 logevent("Pageant is running. Requesting keys.");
6342
6343 /* Request the keys held by the agent. */
51470298 6344 PUT_32BIT(s->request, 1);
6345 s->request[4] = SSH2_AGENTC_REQUEST_IDENTITIES;
839f10db 6346 if (!agent_query(s->request, 5, &r, &s->responselen,
6347 ssh_agent_callback, ssh)) {
6348 do {
6349 crReturnV;
ff3187f6 6350 if (pktin) {
839f10db 6351 bombout(("Unexpected data from server while"
6352 " waiting for agent response"));
6353 crStopV;
6354 }
ff3187f6 6355 } while (pktin || inlen > 0);
839f10db 6356 r = ssh->agent_response;
6357 s->responselen = ssh->agent_response_len;
6358 }
51470298 6359 s->response = (unsigned char *) r;
6360 if (s->response && s->responselen >= 5 &&
6361 s->response[4] == SSH2_AGENT_IDENTITIES_ANSWER) {
6362 s->p = s->response + 5;
6363 s->nkeys = GET_32BIT(s->p);
6364 s->p += 4;
fb983202 6365 logeventf(ssh, "Pageant has %d SSH2 keys", s->nkeys);
51470298 6366 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
2d466ffd 6367 void *vret;
1983e559 6368
fb983202 6369 logeventf(ssh, "Trying Pageant key #%d", s->keyi);
51470298 6370 s->pklen = GET_32BIT(s->p);
6371 s->p += 4;
6372 if (s->publickey_blob &&
6373 s->pklen == s->publickey_bloblen &&
6374 !memcmp(s->p, s->publickey_blob,
6375 s->publickey_bloblen)) {
396778f1 6376 logevent("This key matches configured key file");
51470298 6377 s->tried_pubkey_config = 1;
396778f1 6378 }
d8baa528 6379 s->pkblob = (char *)s->p;
51470298 6380 s->p += s->pklen;
6381 s->alglen = GET_32BIT(s->pkblob);
6382 s->alg = s->pkblob + 4;
6383 s->commentlen = GET_32BIT(s->p);
6384 s->p += 4;
d8baa528 6385 s->commentp = (char *)s->p;
51470298 6386 s->p += s->commentlen;
ff3187f6 6387 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6388 ssh2_pkt_addstring(s->pktout, s->username);
6389 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6390 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6391 ssh2_pkt_addbool(s->pktout, FALSE); /* no signature included */
6392 ssh2_pkt_addstring_start(s->pktout);
6393 ssh2_pkt_addstring_data(s->pktout, s->alg, s->alglen);
6394 ssh2_pkt_addstring_start(s->pktout);
6395 ssh2_pkt_addstring_data(s->pktout, s->pkblob, s->pklen);
6396 ssh2_pkt_send(ssh, s->pktout);
6397
6398 crWaitUntilV(pktin);
6399 if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
1983e559 6400 logevent("Key refused");
6401 continue;
6402 }
6403
32874aea 6404 if (flags & FLAG_VERBOSE) {
51470298 6405 c_write_str(ssh, "Authenticating with "
6406 "public key \"");
6407 c_write(ssh, s->commentp, s->commentlen);
6408 c_write_str(ssh, "\" from agent\r\n");
32874aea 6409 }
1983e559 6410
6411 /*
6412 * Server is willing to accept the key.
6413 * Construct a SIGN_REQUEST.
6414 */
ff3187f6 6415 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6416 ssh2_pkt_addstring(s->pktout, s->username);
6417 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6418 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6419 ssh2_pkt_addbool(s->pktout, TRUE);
6420 ssh2_pkt_addstring_start(s->pktout);
6421 ssh2_pkt_addstring_data(s->pktout, s->alg, s->alglen);
6422 ssh2_pkt_addstring_start(s->pktout);
6423 ssh2_pkt_addstring_data(s->pktout, s->pkblob, s->pklen);
6424
6425 s->siglen = s->pktout->length - 5 + 4 + 20;
dda87a28 6426 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
6427 s->siglen -= 4;
51470298 6428 s->len = 1; /* message type */
6429 s->len += 4 + s->pklen; /* key blob */
6430 s->len += 4 + s->siglen; /* data to sign */
6431 s->len += 4; /* flags */
3d88e64d 6432 s->agentreq = snewn(4 + s->len, char);
51470298 6433 PUT_32BIT(s->agentreq, s->len);
6434 s->q = s->agentreq + 4;
6435 *s->q++ = SSH2_AGENTC_SIGN_REQUEST;
6436 PUT_32BIT(s->q, s->pklen);
6437 s->q += 4;
6438 memcpy(s->q, s->pkblob, s->pklen);
6439 s->q += s->pklen;
6440 PUT_32BIT(s->q, s->siglen);
6441 s->q += 4;
1983e559 6442 /* Now the data to be signed... */
dda87a28 6443 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
6444 PUT_32BIT(s->q, 20);
6445 s->q += 4;
6446 }
51470298 6447 memcpy(s->q, ssh->v2_session_id, 20);
6448 s->q += 20;
ff3187f6 6449 memcpy(s->q, s->pktout->data + 5,
6450 s->pktout->length - 5);
6451 s->q += s->pktout->length - 5;
1983e559 6452 /* And finally the (zero) flags word. */
51470298 6453 PUT_32BIT(s->q, 0);
839f10db 6454 if (!agent_query(s->agentreq, s->len + 4,
6455 &vret, &s->retlen,
6456 ssh_agent_callback, ssh)) {
6457 do {
6458 crReturnV;
ff3187f6 6459 if (pktin) {
839f10db 6460 bombout(("Unexpected data from server"
6461 " while waiting for agent"
6462 " response"));
6463 crStopV;
6464 }
ff3187f6 6465 } while (pktin || inlen > 0);
839f10db 6466 vret = ssh->agent_response;
6467 s->retlen = ssh->agent_response_len;
6468 }
51470298 6469 s->ret = vret;
6470 sfree(s->agentreq);
6471 if (s->ret) {
6472 if (s->ret[4] == SSH2_AGENT_SIGN_RESPONSE) {
1983e559 6473 logevent("Sending Pageant's response");
ff3187f6 6474 ssh2_add_sigblob(ssh, s->pktout,
6475 s->pkblob, s->pklen,
51470298 6476 s->ret + 9,
6477 GET_32BIT(s->ret + 5));
ff3187f6 6478 ssh2_pkt_send(ssh, s->pktout);
51470298 6479 s->authed = TRUE;
1983e559 6480 break;
6481 } else {
32874aea 6482 logevent
6483 ("Pageant failed to answer challenge");
51470298 6484 sfree(s->ret);
1983e559 6485 }
6486 }
6487 }
51470298 6488 if (s->authed)
1983e559 6489 continue;
6490 }
29b1d0b3 6491 sfree(s->response);
1983e559 6492 }
6493
51470298 6494 if (!s->method && s->can_pubkey && s->publickey_blob
6495 && !s->tried_pubkey_config) {
1408a877 6496 unsigned char *pub_blob;
6497 char *algorithm, *comment;
6498 int pub_blob_len;
65a22376 6499
51470298 6500 s->tried_pubkey_config = TRUE;
65a22376 6501
51470298 6502 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6503 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
00db133f 6504
65a22376 6505 /*
1408a877 6506 * Try the public key supplied in the configuration.
6507 *
6508 * First, offer the public blob to see if the server is
6509 * willing to accept it.
65a22376 6510 */
d8baa528 6511 pub_blob =
9a30e26b 6512 (unsigned char *)ssh2_userkey_loadpub(&ssh->cfg.keyfile,
d8baa528 6513 &algorithm,
222d54dc 6514 &pub_blob_len,
6515 NULL);
1408a877 6516 if (pub_blob) {
ff3187f6 6517 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6518 ssh2_pkt_addstring(s->pktout, s->username);
6519 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6520 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6521 ssh2_pkt_addbool(s->pktout, FALSE); /* no signature included */
6522 ssh2_pkt_addstring(s->pktout, algorithm);
6523 ssh2_pkt_addstring_start(s->pktout);
6524 ssh2_pkt_addstring_data(s->pktout, (char *)pub_blob,
d8baa528 6525 pub_blob_len);
ff3187f6 6526 ssh2_pkt_send(ssh, s->pktout);
a03c9f9c 6527 logevent("Offered public key");
1408a877 6528
ff3187f6 6529 crWaitUntilV(pktin);
6530 if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
51470298 6531 s->gotit = TRUE;
6532 s->type = AUTH_TYPE_PUBLICKEY_OFFER_LOUD;
32874aea 6533 continue; /* key refused; give up on it */
1408a877 6534 }
65a22376 6535
1408a877 6536 logevent("Offer of public key accepted");
65a22376 6537 /*
1408a877 6538 * Actually attempt a serious authentication using
6539 * the key.
65a22376 6540 */
9a30e26b 6541 if (ssh2_userkey_encrypted(&ssh->cfg.keyfile, &comment)) {
51470298 6542 sprintf(s->pwprompt,
32874aea 6543 "Passphrase for key \"%.100s\": ",
6544 comment);
51470298 6545 s->need_pw = TRUE;
1408a877 6546 } else {
51470298 6547 s->need_pw = FALSE;
1408a877 6548 }
4e520718 6549 if (flags & FLAG_VERBOSE) {
6550 c_write_str(ssh, "Authenticating with public key \"");
6551 c_write_str(ssh, comment);
6552 c_write_str(ssh, "\"\r\n");
6553 }
51470298 6554 s->method = AUTH_PUBLICKEY_FILE;
65a22376 6555 }
1408a877 6556 }
6557
6f64ce13 6558 if (!s->method && s->can_keyb_inter && !s->kbd_inter_refused &&
6559 !s->kbd_inter_running) {
51470298 6560 s->method = AUTH_KEYBOARD_INTERACTIVE;
6561 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
af659722 6562
51470298 6563 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6564 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
00db133f 6565
ff3187f6 6566 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6567 ssh2_pkt_addstring(s->pktout, s->username);
6568 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6569 ssh2_pkt_addstring(s->pktout, "keyboard-interactive"); /* method */
6570 ssh2_pkt_addstring(s->pktout, ""); /* lang */
6571 ssh2_pkt_addstring(s->pktout, "");
6572 ssh2_pkt_send(ssh, s->pktout);
6573
6574 crWaitUntilV(pktin);
6575 if (pktin->type != SSH2_MSG_USERAUTH_INFO_REQUEST) {
6576 if (pktin->type == SSH2_MSG_USERAUTH_FAILURE)
51470298 6577 s->gotit = TRUE;
af659722 6578 logevent("Keyboard-interactive authentication refused");
51470298 6579 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET;
6ac3a551 6580 s->kbd_inter_refused = TRUE; /* don't try it again */
af659722 6581 continue;
6582 }
6583
51470298 6584 s->kbd_inter_running = TRUE;
6585 s->curr_prompt = 0;
af659722 6586 }
6587
51470298 6588 if (s->kbd_inter_running) {
6589 s->method = AUTH_KEYBOARD_INTERACTIVE;
6590 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
af659722 6591
51470298 6592 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6593 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
00db133f 6594
51470298 6595 if (s->curr_prompt == 0) {
45068b27 6596 /*
6597 * We've got a fresh USERAUTH_INFO_REQUEST.
6598 * Display header data, and start going through
6599 * the prompts.
6600 */
6601 char *name, *inst, *lang;
6602 int name_len, inst_len, lang_len;
6603
ff3187f6 6604 ssh_pkt_getstring(pktin, &name, &name_len);
6605 ssh_pkt_getstring(pktin, &inst, &inst_len);
6606 ssh_pkt_getstring(pktin, &lang, &lang_len);
45068b27 6607 if (name_len > 0) {
51470298 6608 c_write_untrusted(ssh, name, name_len);
6609 c_write_str(ssh, "\r\n");
45068b27 6610 }
6611 if (inst_len > 0) {
51470298 6612 c_write_untrusted(ssh, inst, inst_len);
6613 c_write_str(ssh, "\r\n");
45068b27 6614 }
ff3187f6 6615 s->num_prompts = ssh_pkt_getuint32(pktin);
45068b27 6616 }
af659722 6617
45068b27 6618 /*
6619 * If there are prompts remaining in the packet,
6620 * display one and get a response.
6621 */
51470298 6622 if (s->curr_prompt < s->num_prompts) {
45068b27 6623 char *prompt;
6624 int prompt_len;
af659722 6625
ff3187f6 6626 ssh_pkt_getstring(pktin, &prompt, &prompt_len);
45068b27 6627 if (prompt_len > 0) {
85fdbe25 6628 static const char trunc[] = "<prompt truncated>: ";
6629 static const int prlen = sizeof(s->pwprompt) -
6630 lenof(trunc);
6631 if (prompt_len > prlen) {
6632 memcpy(s->pwprompt, prompt, prlen);
6633 strcpy(s->pwprompt + prlen, trunc);
6634 } else {
6635 memcpy(s->pwprompt, prompt, prompt_len);
6636 s->pwprompt[prompt_len] = '\0';
6637 }
45068b27 6638 } else {
51470298 6639 strcpy(s->pwprompt,
45068b27 6640 "<server failed to send prompt>: ");
6641 }
ff3187f6 6642 s->echo = ssh2_pkt_getbool(pktin);
51470298 6643 s->need_pw = TRUE;
45068b27 6644 } else
51470298 6645 s->need_pw = FALSE;
af659722 6646 }
6647
51470298 6648 if (!s->method && s->can_passwd) {
6649 s->method = AUTH_PASSWORD;
6650 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6651 ssh->pkt_ctx |= SSH2_PKTCTX_PASSWORD;
6652 sprintf(s->pwprompt, "%.90s@%.90s's password: ", s->username,
6653 ssh->savedhost);
6654 s->need_pw = TRUE;
1408a877 6655 }
6656
51470298 6657 if (s->need_pw) {
fa17a66e 6658 if (ssh_get_line) {
51470298 6659 if (!ssh_get_line(s->pwprompt, s->password,
6660 sizeof(s->password), TRUE)) {
1408a877 6661 /*
fa17a66e 6662 * get_line failed to get a password (for
6663 * example because one was supplied on the
6664 * command line which has already failed to
6665 * work). Terminate.
1408a877 6666 */
ff3187f6 6667 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
6668 ssh2_pkt_adduint32(s->pktout,SSH2_DISCONNECT_BY_APPLICATION);
6669 ssh2_pkt_addstring(s->pktout, "No more passwords available"
51470298 6670 " to try");
ff3187f6 6671 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
590f6a5f 6672 ssh2_pkt_send_noqueue(ssh, s->pktout);
247308b5 6673 logevent("Unable to authenticate");
a8327734 6674 connection_fatal(ssh->frontend,
6675 "Unable to authenticate");
ac934965 6676 ssh->close_expected = TRUE;
3bb2f322 6677 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 6678 crStopV;
1408a877 6679 }
6680 } else {
51470298 6681 int ret; /* need not be saved across crReturn */
6682 c_write_untrusted(ssh, s->pwprompt, strlen(s->pwprompt));
6683 ssh->send_ok = 1;
1408a877 6684
51470298 6685 setup_userpass_input(ssh, s->password,
6686 sizeof(s->password), s->echo);
0405e71f 6687 do {
ff3187f6 6688 crWaitUntilV(!pktin);
51470298 6689 ret = process_userpass_input(ssh, in, inlen);
0405e71f 6690 } while (ret == 0);
6691 if (ret < 0)
6692 cleanup_exit(0);
51470298 6693 c_write_str(ssh, "\r\n");
65a22376 6694 }
65a22376 6695 }
65a22376 6696
51470298 6697 if (s->method == AUTH_PUBLICKEY_FILE) {
1408a877 6698 /*
6699 * We have our passphrase. Now try the actual authentication.
6700 */
6701 struct ssh2_userkey *key;
222d54dc 6702 const char *error = NULL;
65a22376 6703
222d54dc 6704 key = ssh2_load_userkey(&ssh->cfg.keyfile, s->password,
6705 &error);
1408a877 6706 if (key == SSH2_WRONG_PASSPHRASE || key == NULL) {
6707 if (key == SSH2_WRONG_PASSPHRASE) {
51470298 6708 c_write_str(ssh, "Wrong passphrase\r\n");
6709 s->tried_pubkey_config = FALSE;
1408a877 6710 } else {
222d54dc 6711 c_write_str(ssh, "Unable to load private key (");
6712 c_write_str(ssh, error);
6713 c_write_str(ssh, ")\r\n");
51470298 6714 s->tried_pubkey_config = TRUE;
1408a877 6715 }
6716 /* Send a spurious AUTH_NONE to return to the top. */
ff3187f6 6717 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6718 ssh2_pkt_addstring(s->pktout, s->username);
6719 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6720 ssh2_pkt_addstring(s->pktout, "none"); /* method */
6721 ssh2_pkt_send(ssh, s->pktout);
51470298 6722 s->type = AUTH_TYPE_NONE;
1408a877 6723 } else {
1dd353b5 6724 unsigned char *pkblob, *sigblob, *sigdata;
6725 int pkblob_len, sigblob_len, sigdata_len;
dda87a28 6726 int p;
65a22376 6727
1408a877 6728 /*
6729 * We have loaded the private key and the server
6730 * has announced that it's willing to accept it.
6731 * Hallelujah. Generate a signature and send it.
6732 */
ff3187f6 6733 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6734 ssh2_pkt_addstring(s->pktout, s->username);
6735 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6736 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6737 ssh2_pkt_addbool(s->pktout, TRUE);
6738 ssh2_pkt_addstring(s->pktout, key->alg->name);
1dd353b5 6739 pkblob = key->alg->public_blob(key->data, &pkblob_len);
ff3187f6 6740 ssh2_pkt_addstring_start(s->pktout);
6741 ssh2_pkt_addstring_data(s->pktout, (char *)pkblob, pkblob_len);
1408a877 6742
6743 /*
6744 * The data to be signed is:
6745 *
6746 * string session-id
6747 *
6748 * followed by everything so far placed in the
6749 * outgoing packet.
6750 */
ff3187f6 6751 sigdata_len = s->pktout->length - 5 + 4 + 20;
dda87a28 6752 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
6753 sigdata_len -= 4;
92d60585 6754 sigdata = snewn(sigdata_len, unsigned char);
dda87a28 6755 p = 0;
6756 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
6757 PUT_32BIT(sigdata+p, 20);
6758 p += 4;
6759 }
6760 memcpy(sigdata+p, ssh->v2_session_id, 20); p += 20;
ff3187f6 6761 memcpy(sigdata+p, s->pktout->data + 5,
6762 s->pktout->length - 5);
6763 p += s->pktout->length - 5;
dda87a28 6764 assert(p == sigdata_len);
d8baa528 6765 sigblob = key->alg->sign(key->data, (char *)sigdata,
1dd353b5 6766 sigdata_len, &sigblob_len);
ff3187f6 6767 ssh2_add_sigblob(ssh, s->pktout, pkblob, pkblob_len,
1dd353b5 6768 sigblob, sigblob_len);
6769 sfree(pkblob);
6770 sfree(sigblob);
1408a877 6771 sfree(sigdata);
6772
ff3187f6 6773 ssh2_pkt_send(ssh, s->pktout);
51470298 6774 s->type = AUTH_TYPE_PUBLICKEY;
75374b2f 6775 key->alg->freekey(key->data);
1408a877 6776 }
51470298 6777 } else if (s->method == AUTH_PASSWORD) {
65a22376 6778 /*
95d2d262 6779 * We pad out the password packet to 256 bytes to make
6780 * it harder for an attacker to find the length of the
6781 * user's password.
1408a877 6782 *
95d2d262 6783 * Anyone using a password longer than 256 bytes
6784 * probably doesn't have much to worry about from
1408a877 6785 * people who find out how long their password is!
65a22376 6786 */
ff3187f6 6787 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
95d2d262 6788 s->pktout->forcepad = 256;
ff3187f6 6789 ssh2_pkt_addstring(s->pktout, s->username);
6790 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6791 ssh2_pkt_addstring(s->pktout, "password");
6792 ssh2_pkt_addbool(s->pktout, FALSE);
6793 dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
6794 ssh2_pkt_addstring(s->pktout, s->password);
1409c1b3 6795 memset(s->password, 0, sizeof(s->password));
ff3187f6 6796 end_log_omission(ssh, s->pktout);
95d2d262 6797 ssh2_pkt_send(ssh, s->pktout);
0d43337a 6798 logevent("Sent password");
51470298 6799 s->type = AUTH_TYPE_PASSWORD;
6800 } else if (s->method == AUTH_KEYBOARD_INTERACTIVE) {
6801 if (s->curr_prompt == 0) {
ff3187f6 6802 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE);
10e09fb5 6803 s->pktout->forcepad = 256;
ff3187f6 6804 ssh2_pkt_adduint32(s->pktout, s->num_prompts);
45068b27 6805 }
51470298 6806 if (s->need_pw) { /* only add pw if we just got one! */
ff3187f6 6807 dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
6808 ssh2_pkt_addstring(s->pktout, s->password);
51470298 6809 memset(s->password, 0, sizeof(s->password));
ff3187f6 6810 end_log_omission(ssh, s->pktout);
51470298 6811 s->curr_prompt++;
45068b27 6812 }
51470298 6813 if (s->curr_prompt >= s->num_prompts) {
ff3187f6 6814 ssh2_pkt_send(ssh, s->pktout);
45068b27 6815 } else {
6816 /*
6817 * If there are prompts remaining, we set
6818 * `gotit' so that we won't attempt to get
6819 * another packet. Then we go back round the
6820 * loop and will end up retrieving another
6821 * prompt out of the existing packet. Funky or
6822 * what?
6823 */
51470298 6824 s->gotit = TRUE;
45068b27 6825 }
51470298 6826 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
1408a877 6827 } else {
51470298 6828 c_write_str(ssh, "No supported authentication methods"
6829 " left to try!\r\n");
6830 logevent("No supported authentications offered."
6831 " Disconnecting");
ff3187f6 6832 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
6833 ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
6834 ssh2_pkt_addstring(s->pktout, "No supported authentication"
51470298 6835 " methods available");
ff3187f6 6836 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
590f6a5f 6837 ssh2_pkt_send_noqueue(ssh, s->pktout);
ac934965 6838 ssh->close_expected = TRUE;
3bb2f322 6839 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 6840 crStopV;
65a22376 6841 }
65a22376 6842 }
51470298 6843 } while (!s->we_are_in);
7cca0d81 6844
6845 /*
6846 * Now we're authenticated for the connection protocol. The
6847 * connection protocol will automatically have started at this
6848 * point; there's no need to send SERVICE_REQUEST.
6849 */
6850
0ed48730 6851 ssh->channels = newtree234(ssh_channelcmp);
6852
7cca0d81 6853 /*
b09eaa88 6854 * Set up handlers for some connection protocol messages, so we
6855 * don't have to handle them repeatedly in this coroutine.
6856 */
6857 ssh->packet_dispatch[SSH2_MSG_CHANNEL_WINDOW_ADJUST] =
6858 ssh2_msg_channel_window_adjust;
51df0ab5 6859 ssh->packet_dispatch[SSH2_MSG_GLOBAL_REQUEST] =
6860 ssh2_msg_global_request;
b09eaa88 6861
6862 /*
0ed48730 6863 * Create the main session channel.
7cca0d81 6864 */
0ed48730 6865 if (!ssh->cfg.ssh_no_shell) {
6866 ssh->mainchan = snew(struct ssh_channel);
6867 ssh->mainchan->ssh = ssh;
6868 ssh->mainchan->localid = alloc_channel_id(ssh);
ff3187f6 6869 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
6870 ssh2_pkt_addstring(s->pktout, "session");
6871 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->localid);
0ed48730 6872 ssh->mainchan->v.v2.locwindow = OUR_V2_WINSIZE;
ff3187f6 6873 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->v.v2.locwindow);/* our window size */
954d5c5a 6874 ssh2_pkt_adduint32(s->pktout, OUR_V2_MAXPKT); /* our max pkt size */
ff3187f6 6875 ssh2_pkt_send(ssh, s->pktout);
6876 crWaitUntilV(pktin);
6877 if (pktin->type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
0ed48730 6878 bombout(("Server refused to open a session"));
6879 crStopV;
6880 /* FIXME: error data comes back in FAILURE packet */
6881 }
ff3187f6 6882 if (ssh_pkt_getuint32(pktin) != ssh->mainchan->localid) {
0ed48730 6883 bombout(("Server's channel confirmation cited wrong channel"));
6884 crStopV;
6885 }
ff3187f6 6886 ssh->mainchan->remoteid = ssh_pkt_getuint32(pktin);
64d6ff88 6887 ssh->mainchan->halfopen = FALSE;
0ed48730 6888 ssh->mainchan->type = CHAN_MAINSESSION;
6889 ssh->mainchan->closes = 0;
ff3187f6 6890 ssh->mainchan->v.v2.remwindow = ssh_pkt_getuint32(pktin);
6891 ssh->mainchan->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin);
0ed48730 6892 bufchain_init(&ssh->mainchan->v.v2.outbuffer);
6893 add234(ssh->channels, ssh->mainchan);
62638676 6894 update_specials_menu(ssh->frontend);
0ed48730 6895 logevent("Opened channel for session");
6896 } else
6897 ssh->mainchan = NULL;
7cca0d81 6898
6899 /*
51df0ab5 6900 * Now we have a channel, make dispatch table entries for
6901 * general channel-based messages.
6902 */
6903 ssh->packet_dispatch[SSH2_MSG_CHANNEL_DATA] =
6904 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EXTENDED_DATA] =
6905 ssh2_msg_channel_data;
6906 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EOF] = ssh2_msg_channel_eof;
6907 ssh->packet_dispatch[SSH2_MSG_CHANNEL_CLOSE] = ssh2_msg_channel_close;
6908 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION] =
6909 ssh2_msg_channel_open_confirmation;
6910 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_FAILURE] =
6911 ssh2_msg_channel_open_failure;
6912 ssh->packet_dispatch[SSH2_MSG_CHANNEL_REQUEST] =
6913 ssh2_msg_channel_request;
6914 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN] =
6915 ssh2_msg_channel_open;
6916
6917 /*
783415f8 6918 * Potentially enable X11 forwarding.
6919 */
0ed48730 6920 if (ssh->mainchan && ssh->cfg.x11_forward) {
32874aea 6921 char proto[20], data[64];
6922 logevent("Requesting X11 forwarding");
302121de 6923 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
86916870 6924 data, sizeof(data), ssh->cfg.x11_auth);
6925 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
ff3187f6 6926 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
6927 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
6928 ssh2_pkt_addstring(s->pktout, "x11-req");
6929 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
6930 ssh2_pkt_addbool(s->pktout, 0); /* many connections */
6931 ssh2_pkt_addstring(s->pktout, proto);
6932 ssh2_pkt_addstring(s->pktout, data);
6933 ssh2_pkt_adduint32(s->pktout, x11_get_screen_number(ssh->cfg.x11_display));
6934 ssh2_pkt_send(ssh, s->pktout);
32874aea 6935
b09eaa88 6936 crWaitUntilV(pktin);
32874aea 6937
ff3187f6 6938 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
6939 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 6940 bombout(("Unexpected response to X11 forwarding request:"
ff3187f6 6941 " packet type %d", pktin->type));
7ffdbc1a 6942 crStopV;
32874aea 6943 }
6944 logevent("X11 forwarding refused");
6945 } else {
6946 logevent("X11 forwarding enabled");
51470298 6947 ssh->X11_fwd_enabled = TRUE;
32874aea 6948 }
783415f8 6949 }
6950
6951 /*
bc240b21 6952 * Enable port forwardings.
6953 */
06fadff5 6954 ssh_setup_portfwd(ssh, &ssh->cfg);
bc240b21 6955
6956 /*
36c2a3e9 6957 * Potentially enable agent forwarding.
6958 */
0ed48730 6959 if (ssh->mainchan && ssh->cfg.agentfwd && agent_exists()) {
32874aea 6960 logevent("Requesting OpenSSH-style agent forwarding");
ff3187f6 6961 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
6962 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
6963 ssh2_pkt_addstring(s->pktout, "auth-agent-req@openssh.com");
6964 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
6965 ssh2_pkt_send(ssh, s->pktout);
32874aea 6966
b09eaa88 6967 crWaitUntilV(pktin);
32874aea 6968
ff3187f6 6969 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
6970 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 6971 bombout(("Unexpected response to agent forwarding request:"
ff3187f6 6972 " packet type %d", pktin->type));
7ffdbc1a 6973 crStopV;
32874aea 6974 }
6975 logevent("Agent forwarding refused");
6976 } else {
6977 logevent("Agent forwarding enabled");
51470298 6978 ssh->agentfwd_enabled = TRUE;
32874aea 6979 }
36c2a3e9 6980 }
6981
6982 /*
7cca0d81 6983 * Now allocate a pty for the session.
6984 */
0ed48730 6985 if (ssh->mainchan && !ssh->cfg.nopty) {
a5dd8467 6986 /* Unpick the terminal-speed string. */
6987 /* XXX perhaps we should allow no speeds to be sent. */
db219738 6988 ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
6989 sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
a5dd8467 6990 /* Build the pty request. */
ff3187f6 6991 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
6992 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid); /* recipient channel */
6993 ssh2_pkt_addstring(s->pktout, "pty-req");
6994 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
6995 ssh2_pkt_addstring(s->pktout, ssh->cfg.termtype);
6996 ssh2_pkt_adduint32(s->pktout, ssh->term_width);
6997 ssh2_pkt_adduint32(s->pktout, ssh->term_height);
6998 ssh2_pkt_adduint32(s->pktout, 0); /* pixel width */
6999 ssh2_pkt_adduint32(s->pktout, 0); /* pixel height */
7000 ssh2_pkt_addstring_start(s->pktout);
7001 ssh2_pkt_addbyte(s->pktout, 128); /* TTY_OP_ISPEED */
7002 ssh2_pkt_adduint32(s->pktout, ssh->ispeed);
7003 ssh2_pkt_addbyte(s->pktout, 129); /* TTY_OP_OSPEED */
7004 ssh2_pkt_adduint32(s->pktout, ssh->ospeed);
7005 ssh2_pkt_addstring_data(s->pktout, "\0", 1); /* TTY_OP_END */
7006 ssh2_pkt_send(ssh, s->pktout);
51470298 7007 ssh->state = SSH_STATE_INTERMED;
32874aea 7008
b09eaa88 7009 crWaitUntilV(pktin);
32874aea 7010
ff3187f6 7011 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
7012 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 7013 bombout(("Unexpected response to pty request:"
ff3187f6 7014 " packet type %d", pktin->type));
7ffdbc1a 7015 crStopV;
32874aea 7016 }
51470298 7017 c_write_str(ssh, "Server refused to allocate pty\r\n");
7018 ssh->editing = ssh->echoing = 1;
32874aea 7019 } else {
a5dd8467 7020 logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
db219738 7021 ssh->ospeed, ssh->ispeed);
32874aea 7022 }
0965bee0 7023 } else {
51470298 7024 ssh->editing = ssh->echoing = 1;
7cca0d81 7025 }
7026
7027 /*
73feed4f 7028 * Send environment variables.
7029 *
7030 * Simplest thing here is to send all the requests at once, and
7031 * then wait for a whole bunch of successes or failures.
7032 */
7033 if (ssh->mainchan && *ssh->cfg.environmt) {
7034 char *e = ssh->cfg.environmt;
7035 char *var, *varend, *val;
7036
7037 s->num_env = 0;
7038
7039 while (*e) {
7040 var = e;
7041 while (*e && *e != '\t') e++;
7042 varend = e;
7043 if (*e == '\t') e++;
7044 val = e;
7045 while (*e) e++;
7046 e++;
7047
ff3187f6 7048 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7049 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
7050 ssh2_pkt_addstring(s->pktout, "env");
7051 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7052 ssh2_pkt_addstring_start(s->pktout);
7053 ssh2_pkt_addstring_data(s->pktout, var, varend-var);
7054 ssh2_pkt_addstring(s->pktout, val);
7055 ssh2_pkt_send(ssh, s->pktout);
73feed4f 7056
7057 s->num_env++;
7058 }
7059
7060 logeventf(ssh, "Sent %d environment variables", s->num_env);
7061
7062 s->env_ok = 0;
7063 s->env_left = s->num_env;
7064
7065 while (s->env_left > 0) {
b09eaa88 7066 crWaitUntilV(pktin);
73feed4f 7067
ff3187f6 7068 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
7069 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
73feed4f 7070 bombout(("Unexpected response to environment request:"
ff3187f6 7071 " packet type %d", pktin->type));
73feed4f 7072 crStopV;
7073 }
7074 } else {
7075 s->env_ok++;
7076 }
7077
7078 s->env_left--;
7079 }
7080
7081 if (s->env_ok == s->num_env) {
7082 logevent("All environment variables successfully set");
7083 } else if (s->env_ok == 0) {
7084 logevent("All environment variables refused");
7085 c_write_str(ssh, "Server refused to set environment variables\r\n");
7086 } else {
7087 logeventf(ssh, "%d environment variables refused",
7088 s->num_env - s->env_ok);
7089 c_write_str(ssh, "Server refused to set all environment variables\r\n");
7090 }
7091 }
7092
7093 /*
fd5e5847 7094 * Start a shell or a remote command. We may have to attempt
7095 * this twice if the config data has provided a second choice
7096 * of command.
7cca0d81 7097 */
0ed48730 7098 if (ssh->mainchan) while (1) {
fd5e5847 7099 int subsys;
7100 char *cmd;
7101
51470298 7102 if (ssh->fallback_cmd) {
86916870 7103 subsys = ssh->cfg.ssh_subsys2;
7104 cmd = ssh->cfg.remote_cmd_ptr2;
fd5e5847 7105 } else {
86916870 7106 subsys = ssh->cfg.ssh_subsys;
7107 cmd = ssh->cfg.remote_cmd_ptr;
fd5e5847 7108 }
7109
ff3187f6 7110 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7111 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid); /* recipient channel */
fd5e5847 7112 if (subsys) {
ff3187f6 7113 ssh2_pkt_addstring(s->pktout, "subsystem");
7114 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7115 ssh2_pkt_addstring(s->pktout, cmd);
fd5e5847 7116 } else if (*cmd) {
ff3187f6 7117 ssh2_pkt_addstring(s->pktout, "exec");
7118 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7119 ssh2_pkt_addstring(s->pktout, cmd);
fd5e5847 7120 } else {
ff3187f6 7121 ssh2_pkt_addstring(s->pktout, "shell");
7122 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
32874aea 7123 }
ff3187f6 7124 ssh2_pkt_send(ssh, s->pktout);
b09eaa88 7125
7126 crWaitUntilV(pktin);
7127
ff3187f6 7128 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
7129 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 7130 bombout(("Unexpected response to shell/command request:"
ff3187f6 7131 " packet type %d", pktin->type));
7ffdbc1a 7132 crStopV;
fd5e5847 7133 }
7134 /*
7135 * We failed to start the command. If this is the
7136 * fallback command, we really are finished; if it's
7137 * not, and if the fallback command exists, try falling
7138 * back to it before complaining.
7139 */
86916870 7140 if (!ssh->fallback_cmd && ssh->cfg.remote_cmd_ptr2 != NULL) {
fd5e5847 7141 logevent("Primary command failed; attempting fallback");
51470298 7142 ssh->fallback_cmd = TRUE;
fd5e5847 7143 continue;
7144 }
6b5cf8b4 7145 bombout(("Server refused to start a shell/command"));
7ffdbc1a 7146 crStopV;
fd5e5847 7147 } else {
7148 logevent("Started a shell/command");
32874aea 7149 }
fd5e5847 7150 break;
7cca0d81 7151 }
7152
51470298 7153 ssh->state = SSH_STATE_SESSION;
7154 if (ssh->size_needed)
7155 ssh_size(ssh, ssh->term_width, ssh->term_height);
7156 if (ssh->eof_needed)
7157 ssh_special(ssh, TS_EOF);
6e48c3fe 7158
7cca0d81 7159 /*
7160 * Transfer data!
7161 */
b9d7bcad 7162 if (ssh->ldisc)
7163 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
0ed48730 7164 if (ssh->mainchan)
7165 ssh->send_ok = 1;
7cca0d81 7166 while (1) {
e5574168 7167 crReturnV;
51470298 7168 s->try_send = FALSE;
ff3187f6 7169 if (pktin) {
2b7540a7 7170
51df0ab5 7171 /*
7172 * _All_ the connection-layer packets we expect to
7173 * receive are now handled by the dispatch table.
7174 * Anything that reaches here must be bogus.
7175 */
32874aea 7176
51df0ab5 7177 bombout(("Strange packet received: type %d", pktin->type));
7178 crStopV;
0ed48730 7179 } else if (ssh->mainchan) {
32874aea 7180 /*
7181 * We have spare data. Add it to the channel buffer.
7182 */
d8baa528 7183 ssh2_add_channel_data(ssh->mainchan, (char *)in, inlen);
51470298 7184 s->try_send = TRUE;
32874aea 7185 }
51470298 7186 if (s->try_send) {
32874aea 7187 int i;
7188 struct ssh_channel *c;
7189 /*
7190 * Try to send data on all channels if we can.
7191 */
51470298 7192 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
a6253970 7193 int bufsize;
7194 if (c->closes)
7195 continue; /* don't send on closing channels */
7196 bufsize = ssh2_try_send(c);
5471d09a 7197 if (bufsize == 0) {
7198 switch (c->type) {
7199 case CHAN_MAINSESSION:
7200 /* stdin need not receive an unthrottle
7201 * notification since it will be polled */
7202 break;
7203 case CHAN_X11:
7204 x11_unthrottle(c->u.x11.s);
7205 break;
7206 case CHAN_AGENT:
7207 /* agent sockets are request/response and need no
7208 * buffer management */
7209 break;
7210 case CHAN_SOCKDATA:
7211 pfd_unthrottle(c->u.pfd.s);
7212 break;
7213 }
7214 }
7215 }
7cca0d81 7216 }
e5574168 7217 }
7218
7219 crFinishV;
7220}
7221
7222/*
b09eaa88 7223 * Handlers for SSH2 messages that might arrive at any moment.
7224 */
409bfa77 7225static void ssh2_msg_disconnect(Ssh ssh, struct Packet *pktin)
b09eaa88 7226{
7227 /* log reason code in disconnect message */
7228 char *buf, *msg;
7229 int nowlen, reason, msglen;
7230
7231 reason = ssh_pkt_getuint32(pktin);
7232 ssh_pkt_getstring(pktin, &msg, &msglen);
7233
7234 if (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) {
7235 buf = dupprintf("Received disconnect message (%s)",
7236 ssh2_disconnect_reasons[reason]);
7237 } else {
7238 buf = dupprintf("Received disconnect message (unknown"
7239 " type %d)", reason);
7240 }
7241 logevent(buf);
7242 sfree(buf);
7243 buf = dupprintf("Disconnection message text: %n%.*s",
7244 &nowlen, msglen, msg);
7245 logevent(buf);
7246 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
7247 reason,
7248 (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) ?
7249 ssh2_disconnect_reasons[reason] : "unknown",
7250 buf+nowlen));
7251 sfree(buf);
7252}
7253
409bfa77 7254static void ssh2_msg_debug(Ssh ssh, struct Packet *pktin)
b09eaa88 7255{
7256 /* log the debug message */
fb983202 7257 char *msg;
b09eaa88 7258 int msglen;
7259 int always_display;
7260
7261 /* XXX maybe we should actually take notice of this */
7262 always_display = ssh2_pkt_getbool(pktin);
7263 ssh_pkt_getstring(pktin, &msg, &msglen);
7264
fb983202 7265 logeventf(ssh, "Remote debug message: %.*s", msglen, msg);
b09eaa88 7266}
7267
409bfa77 7268static void ssh2_msg_something_unimplemented(Ssh ssh, struct Packet *pktin)
b09eaa88 7269{
7270 struct Packet *pktout;
7271 pktout = ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED);
7272 ssh2_pkt_adduint32(pktout, pktin->sequence);
7273 /*
7274 * UNIMPLEMENTED messages MUST appear in the same order as the
7275 * messages they respond to. Hence, never queue them.
7276 */
7277 ssh2_pkt_send_noqueue(ssh, pktout);
7278}
7279
7280/*
7cca0d81 7281 * Handle the top-level SSH2 protocol.
7282 */
b09eaa88 7283static void ssh2_protocol_setup(Ssh ssh)
7284{
7285 int i;
7286
7287 /*
7288 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
7289 */
7290 for (i = 0; i < 256; i++)
7291 ssh->packet_dispatch[i] = ssh2_msg_something_unimplemented;
7292
7293 /*
7294 * Any message we actually understand, we set to NULL so that
7295 * the coroutines will get it.
7296 */
7297 ssh->packet_dispatch[SSH2_MSG_UNIMPLEMENTED] = NULL;
7298 ssh->packet_dispatch[SSH2_MSG_SERVICE_REQUEST] = NULL;
7299 ssh->packet_dispatch[SSH2_MSG_SERVICE_ACCEPT] = NULL;
7300 ssh->packet_dispatch[SSH2_MSG_KEXINIT] = NULL;
7301 ssh->packet_dispatch[SSH2_MSG_NEWKEYS] = NULL;
7302 ssh->packet_dispatch[SSH2_MSG_KEXDH_INIT] = NULL;
7303 ssh->packet_dispatch[SSH2_MSG_KEXDH_REPLY] = NULL;
7304 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
7305 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
7306 ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_INIT] = NULL;
7307 ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REPLY] = NULL;
7308 ssh->packet_dispatch[SSH2_MSG_USERAUTH_REQUEST] = NULL;
7309 ssh->packet_dispatch[SSH2_MSG_USERAUTH_FAILURE] = NULL;
7310 ssh->packet_dispatch[SSH2_MSG_USERAUTH_SUCCESS] = NULL;
7311 ssh->packet_dispatch[SSH2_MSG_USERAUTH_BANNER] = NULL;
7312 ssh->packet_dispatch[SSH2_MSG_USERAUTH_PK_OK] = NULL;
7313 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
7314 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
7315 ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_RESPONSE] = NULL;
7316 ssh->packet_dispatch[SSH2_MSG_GLOBAL_REQUEST] = NULL;
7317 ssh->packet_dispatch[SSH2_MSG_REQUEST_SUCCESS] = NULL;
7318 ssh->packet_dispatch[SSH2_MSG_REQUEST_FAILURE] = NULL;
7319 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN] = NULL;
7320 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION] = NULL;
7321 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_FAILURE] = NULL;
7322 ssh->packet_dispatch[SSH2_MSG_CHANNEL_WINDOW_ADJUST] = NULL;
7323 ssh->packet_dispatch[SSH2_MSG_CHANNEL_DATA] = NULL;
7324 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EXTENDED_DATA] = NULL;
7325 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EOF] = NULL;
7326 ssh->packet_dispatch[SSH2_MSG_CHANNEL_CLOSE] = NULL;
7327 ssh->packet_dispatch[SSH2_MSG_CHANNEL_REQUEST] = NULL;
7328 ssh->packet_dispatch[SSH2_MSG_CHANNEL_SUCCESS] = NULL;
7329 ssh->packet_dispatch[SSH2_MSG_CHANNEL_FAILURE] = NULL;
7330
7331 /*
7332 * These special message types we install handlers for.
7333 */
7334 ssh->packet_dispatch[SSH2_MSG_DISCONNECT] = ssh2_msg_disconnect;
7335 ssh->packet_dispatch[SSH2_MSG_IGNORE] = ssh_msg_ignore; /* shared with ssh1 */
7336 ssh->packet_dispatch[SSH2_MSG_DEBUG] = ssh2_msg_debug;
7337}
7338
9442dd57 7339static void ssh2_timer(void *ctx, long now)
7340{
7341 Ssh ssh = (Ssh)ctx;
7342
e6c1536e 7343 if (!ssh->kex_in_progress && ssh->cfg.ssh_rekey_time != 0 &&
9442dd57 7344 now - ssh->next_rekey >= 0) {
f382c87d 7345 do_ssh2_transport(ssh, "timeout", -1, NULL);
9442dd57 7346 }
7347}
7348
1c1a7262 7349static void ssh2_protocol(Ssh ssh, void *vin, int inlen,
ff3187f6 7350 struct Packet *pktin)
7cca0d81 7351{
1c1a7262 7352 unsigned char *in = (unsigned char *)vin;
b09eaa88 7353 if (ssh->state == SSH_STATE_CLOSED)
7354 return;
7355
9442dd57 7356 if (pktin) {
7357 ssh->incoming_data_size += pktin->encrypted_len;
7358 if (!ssh->kex_in_progress &&
d57f70af 7359 ssh->max_data_size != 0 &&
7360 ssh->incoming_data_size > ssh->max_data_size)
f382c87d 7361 do_ssh2_transport(ssh, "too much data received", -1, NULL);
9442dd57 7362 }
7363
b09eaa88 7364 if (pktin && ssh->packet_dispatch[pktin->type]) {
7365 ssh->packet_dispatch[pktin->type](ssh, pktin);
32874aea 7366 return;
b09eaa88 7367 }
7368
7369 if (!ssh->protocol_initial_phase_done ||
7370 (pktin && pktin->type >= 20 && pktin->type < 50)) {
7371 if (do_ssh2_transport(ssh, in, inlen, pktin) &&
7372 !ssh->protocol_initial_phase_done) {
7373 ssh->protocol_initial_phase_done = TRUE;
7374 /*
7375 * Allow authconn to initialise itself.
7376 */
7377 do_ssh2_authconn(ssh, NULL, 0, NULL);
7378 }
7379 } else {
7380 do_ssh2_authconn(ssh, in, inlen, pktin);
7381 }
7cca0d81 7382}
7383
7384/*
8df7a775 7385 * Called to set up the connection.
374330e2 7386 *
7387 * Returns an error message, or NULL on success.
374330e2 7388 */
cbe2d68f 7389static const char *ssh_init(void *frontend_handle, void **backend_handle,
7390 Config *cfg,
79bf227b 7391 char *host, int port, char **realhost, int nodelay,
7392 int keepalive)
32874aea 7393{
cbe2d68f 7394 const char *p;
51470298 7395 Ssh ssh;
7396
3d88e64d 7397 ssh = snew(struct ssh_tag);
86916870 7398 ssh->cfg = *cfg; /* STRUCTURE COPY */
125105d1 7399 ssh->version = 0; /* when not ready yet */
51470298 7400 ssh->s = NULL;
7401 ssh->cipher = NULL;
371e569c 7402 ssh->v1_cipher_ctx = NULL;
0183b242 7403 ssh->crcda_ctx = NULL;
51470298 7404 ssh->cscipher = NULL;
371e569c 7405 ssh->cs_cipher_ctx = NULL;
51470298 7406 ssh->sccipher = NULL;
371e569c 7407 ssh->sc_cipher_ctx = NULL;
51470298 7408 ssh->csmac = NULL;
a8327734 7409 ssh->cs_mac_ctx = NULL;
51470298 7410 ssh->scmac = NULL;
e0e1a00d 7411 ssh->sc_mac_ctx = NULL;
51470298 7412 ssh->cscomp = NULL;
5366aed8 7413 ssh->cs_comp_ctx = NULL;
51470298 7414 ssh->sccomp = NULL;
5366aed8 7415 ssh->sc_comp_ctx = NULL;
51470298 7416 ssh->kex = NULL;
389aa499 7417 ssh->kex_ctx = NULL;
51470298 7418 ssh->hostkey = NULL;
7419 ssh->exitcode = -1;
ac934965 7420 ssh->close_expected = FALSE;
51470298 7421 ssh->state = SSH_STATE_PREPACKET;
7422 ssh->size_needed = FALSE;
7423 ssh->eof_needed = FALSE;
b9d7bcad 7424 ssh->ldisc = NULL;
a8327734 7425 ssh->logctx = NULL;
51470298 7426 ssh->deferred_send_data = NULL;
7427 ssh->deferred_len = 0;
7428 ssh->deferred_size = 0;
7429 ssh->fallback_cmd = 0;
7430 ssh->pkt_ctx = 0;
302121de 7431 ssh->x11auth = NULL;
be738459 7432 ssh->v1_compressing = FALSE;
51470298 7433 ssh->v2_outgoing_sequence = 0;
7434 ssh->ssh1_rdpkt_crstate = 0;
7435 ssh->ssh2_rdpkt_crstate = 0;
7436 ssh->do_ssh_init_crstate = 0;
7437 ssh->ssh_gotdata_crstate = 0;
b09eaa88 7438 ssh->do_ssh1_connection_crstate = 0;
51470298 7439 ssh->do_ssh1_login_crstate = 0;
7440 ssh->do_ssh2_transport_crstate = 0;
7441 ssh->do_ssh2_authconn_crstate = 0;
7442 ssh->do_ssh_init_state = NULL;
7443 ssh->do_ssh1_login_state = NULL;
7444 ssh->do_ssh2_transport_state = NULL;
7445 ssh->do_ssh2_authconn_state = NULL;
6571dbfd 7446 ssh->mainchan = NULL;
968d2d92 7447 ssh->throttled_all = 0;
7448 ssh->v1_stdout_throttling = 0;
590f6a5f 7449 ssh->queue = NULL;
7450 ssh->queuelen = ssh->queuesize = 0;
7451 ssh->queueing = FALSE;
06fadff5 7452 ssh->qhead = ssh->qtail = NULL;
e13bba36 7453 ssh->deferred_rekey_reason = NULL;
51470298 7454
7455 *backend_handle = ssh;
32874aea 7456
8f203108 7457#ifdef MSCRYPTOAPI
32874aea 7458 if (crypto_startup() == 0)
8f203108 7459 return "Microsoft high encryption pack not installed!";
7460#endif
374330e2 7461
51470298 7462 ssh->frontend = frontend_handle;
86916870 7463 ssh->term_width = ssh->cfg.width;
7464 ssh->term_height = ssh->cfg.height;
887035a5 7465
fabd1805 7466 ssh->channels = NULL;
7467 ssh->rportfwds = NULL;
f47a5ffb 7468 ssh->portfwds = NULL;
fabd1805 7469
51470298 7470 ssh->send_ok = 0;
7471 ssh->editing = 0;
7472 ssh->echoing = 0;
7473 ssh->v1_throttle_count = 0;
7474 ssh->overall_bufsize = 0;
7475 ssh->fallback_cmd = 0;
8df7a775 7476
3648d4c5 7477 ssh->protocol = NULL;
7478
b09eaa88 7479 ssh->protocol_initial_phase_done = FALSE;
7480
39934deb 7481 ssh->pinger = NULL;
7482
9442dd57 7483 ssh->incoming_data_size = ssh->outgoing_data_size =
7484 ssh->deferred_data_size = 0L;
d57f70af 7485 ssh->max_data_size = parse_blocksize(ssh->cfg.ssh_rekey_data);
9442dd57 7486 ssh->kex_in_progress = FALSE;
7487
79bf227b 7488 p = connect_to_host(ssh, host, port, realhost, nodelay, keepalive);
fb09bf1c 7489 if (p != NULL)
7490 return p;
374330e2 7491
5d17ccfc 7492 random_ref();
7493
374330e2 7494 return NULL;
7495}
7496
fabd1805 7497static void ssh_free(void *handle)
7498{
7499 Ssh ssh = (Ssh) handle;
7500 struct ssh_channel *c;
7501 struct ssh_rportfwd *pf;
7502
7503 if (ssh->v1_cipher_ctx)
7504 ssh->cipher->free_context(ssh->v1_cipher_ctx);
7505 if (ssh->cs_cipher_ctx)
7506 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
7507 if (ssh->sc_cipher_ctx)
7508 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
7509 if (ssh->cs_mac_ctx)
7510 ssh->csmac->free_context(ssh->cs_mac_ctx);
7511 if (ssh->sc_mac_ctx)
7512 ssh->scmac->free_context(ssh->sc_mac_ctx);
29b1d0b3 7513 if (ssh->cs_comp_ctx) {
7514 if (ssh->cscomp)
7515 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
7516 else
7517 zlib_compress_cleanup(ssh->cs_comp_ctx);
7518 }
7519 if (ssh->sc_comp_ctx) {
7520 if (ssh->sccomp)
7521 ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
7522 else
7523 zlib_decompress_cleanup(ssh->sc_comp_ctx);
7524 }
fabd1805 7525 if (ssh->kex_ctx)
7526 dh_cleanup(ssh->kex_ctx);
7527 sfree(ssh->savedhost);
7528
590f6a5f 7529 while (ssh->queuelen-- > 0)
7530 ssh_free_packet(ssh->queue[ssh->queuelen]);
7531 sfree(ssh->queue);
7532
06fadff5 7533 while (ssh->qhead) {
7534 struct queued_handler *qh = ssh->qhead;
7535 ssh->qhead = qh->next;
7536 sfree(ssh->qhead);
7537 }
7538 ssh->qhead = ssh->qtail = NULL;
7539
fabd1805 7540 if (ssh->channels) {
7541 while ((c = delpos234(ssh->channels, 0)) != NULL) {
7542 switch (c->type) {
7543 case CHAN_X11:
7544 if (c->u.x11.s != NULL)
7545 x11_close(c->u.x11.s);
7546 break;
7547 case CHAN_SOCKDATA:
7548 if (c->u.pfd.s != NULL)
7549 pfd_close(c->u.pfd.s);
7550 break;
7551 }
7552 sfree(c);
7553 }
7554 freetree234(ssh->channels);
cdb52705 7555 ssh->channels = NULL;
fabd1805 7556 }
7557
7558 if (ssh->rportfwds) {
7559 while ((pf = delpos234(ssh->rportfwds, 0)) != NULL)
7560 sfree(pf);
7561 freetree234(ssh->rportfwds);
cdb52705 7562 ssh->rportfwds = NULL;
fabd1805 7563 }
7564 sfree(ssh->deferred_send_data);
7565 if (ssh->x11auth)
7566 x11_free_auth(ssh->x11auth);
7567 sfree(ssh->do_ssh_init_state);
7568 sfree(ssh->do_ssh1_login_state);
7569 sfree(ssh->do_ssh2_transport_state);
7570 sfree(ssh->do_ssh2_authconn_state);
679539d7 7571 if (ssh->crcda_ctx) {
7572 crcda_free_context(ssh->crcda_ctx);
7573 ssh->crcda_ctx = NULL;
7574 }
fabd1805 7575 if (ssh->s)
ac934965 7576 ssh_do_close(ssh, TRUE);
9442dd57 7577 expire_timer_context(ssh);
39934deb 7578 if (ssh->pinger)
7579 pinger_free(ssh->pinger);
ee50e8b6 7580 sfree(ssh);
5d17ccfc 7581
7582 random_unref();
fabd1805 7583}
7584
374330e2 7585/*
86916870 7586 * Reconfigure the SSH backend.
86916870 7587 */
7588static void ssh_reconfig(void *handle, Config *cfg)
7589{
7590 Ssh ssh = (Ssh) handle;
e13bba36 7591 char *rekeying = NULL, rekey_mandatory = FALSE;
e6c1536e 7592 unsigned long old_max_data_size;
7593
39934deb 7594 pinger_reconfig(ssh->pinger, &ssh->cfg, cfg);
fda2feb1 7595 ssh_setup_portfwd(ssh, cfg);
e6c1536e 7596
7597 if (ssh->cfg.ssh_rekey_time != cfg->ssh_rekey_time &&
7598 cfg->ssh_rekey_time != 0) {
7599 long new_next = ssh->last_rekey + cfg->ssh_rekey_time*60*TICKSPERSEC;
7600 long now = GETTICKCOUNT();
7601
7602 if (new_next - now < 0) {
f382c87d 7603 rekeying = "timeout shortened";
e6c1536e 7604 } else {
7605 ssh->next_rekey = schedule_timer(new_next - now, ssh2_timer, ssh);
7606 }
7607 }
7608
7609 old_max_data_size = ssh->max_data_size;
7610 ssh->max_data_size = parse_blocksize(cfg->ssh_rekey_data);
7611 if (old_max_data_size != ssh->max_data_size &&
7612 ssh->max_data_size != 0) {
7613 if (ssh->outgoing_data_size > ssh->max_data_size ||
7614 ssh->incoming_data_size > ssh->max_data_size)
f382c87d 7615 rekeying = "data limit lowered";
e6c1536e 7616 }
7617
e13bba36 7618 if (ssh->cfg.compression != cfg->compression) {
f382c87d 7619 rekeying = "compression setting changed";
e13bba36 7620 rekey_mandatory = TRUE;
7621 }
7622
7623 if (ssh->cfg.ssh2_des_cbc != cfg->ssh2_des_cbc ||
7624 memcmp(ssh->cfg.ssh_cipherlist, cfg->ssh_cipherlist,
7625 sizeof(ssh->cfg.ssh_cipherlist))) {
f382c87d 7626 rekeying = "cipher settings changed";
e13bba36 7627 rekey_mandatory = TRUE;
e6c1536e 7628 }
7629
86916870 7630 ssh->cfg = *cfg; /* STRUCTURE COPY */
e13bba36 7631
7632 if (rekeying) {
7633 if (!ssh->kex_in_progress) {
7634 do_ssh2_transport(ssh, rekeying, -1, NULL);
7635 } else if (rekey_mandatory) {
7636 ssh->deferred_rekey_reason = rekeying;
7637 }
7638 }
86916870 7639}
7640
7641/*
374330e2 7642 * Called to send data down the Telnet connection.
7643 */
51470298 7644static int ssh_send(void *handle, char *buf, int len)
32874aea 7645{
51470298 7646 Ssh ssh = (Ssh) handle;
7647
7648 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
5471d09a 7649 return 0;
374330e2 7650
d8baa528 7651 ssh->protocol(ssh, (unsigned char *)buf, len, 0);
5471d09a 7652
51470298 7653 return ssh_sendbuffer(ssh);
5471d09a 7654}
7655
7656/*
7657 * Called to query the current amount of buffered stdin data.
7658 */
51470298 7659static int ssh_sendbuffer(void *handle)
5471d09a 7660{
51470298 7661 Ssh ssh = (Ssh) handle;
5471d09a 7662 int override_value;
7663
51470298 7664 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
5471d09a 7665 return 0;
7666
7667 /*
7668 * If the SSH socket itself has backed up, add the total backup
7669 * size on that to any individual buffer on the stdin channel.
7670 */
7671 override_value = 0;
51470298 7672 if (ssh->throttled_all)
7673 override_value = ssh->overall_bufsize;
5471d09a 7674
51470298 7675 if (ssh->version == 1) {
5471d09a 7676 return override_value;
51470298 7677 } else if (ssh->version == 2) {
7678 if (!ssh->mainchan || ssh->mainchan->closes > 0)
5471d09a 7679 return override_value;
7680 else
51470298 7681 return (override_value +
7682 bufchain_size(&ssh->mainchan->v.v2.outbuffer));
5471d09a 7683 }
7684
7685 return 0;
374330e2 7686}
7687
7688/*
6e48c3fe 7689 * Called to set the size of the window from SSH's POV.
374330e2 7690 */
51470298 7691static void ssh_size(void *handle, int width, int height)
32874aea 7692{
51470298 7693 Ssh ssh = (Ssh) handle;
ff3187f6 7694 struct Packet *pktout;
51470298 7695
7696 ssh->term_width = width;
7697 ssh->term_height = height;
f278d6f8 7698
51470298 7699 switch (ssh->state) {
374330e2 7700 case SSH_STATE_BEFORE_SIZE:
3687d221 7701 case SSH_STATE_PREPACKET:
21248260 7702 case SSH_STATE_CLOSED:
374330e2 7703 break; /* do nothing */
7704 case SSH_STATE_INTERMED:
51470298 7705 ssh->size_needed = TRUE; /* buffer for later */
374330e2 7706 break;
7707 case SSH_STATE_SESSION:
86916870 7708 if (!ssh->cfg.nopty) {
51470298 7709 if (ssh->version == 1) {
7710 send_packet(ssh, SSH1_CMSG_WINDOW_SIZE,
7711 PKT_INT, ssh->term_height,
7712 PKT_INT, ssh->term_width,
32874aea 7713 PKT_INT, 0, PKT_INT, 0, PKT_END);
0ed48730 7714 } else if (ssh->mainchan) {
ff3187f6 7715 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7716 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7717 ssh2_pkt_addstring(pktout, "window-change");
7718 ssh2_pkt_addbool(pktout, 0);
7719 ssh2_pkt_adduint32(pktout, ssh->term_width);
7720 ssh2_pkt_adduint32(pktout, ssh->term_height);
7721 ssh2_pkt_adduint32(pktout, 0);
7722 ssh2_pkt_adduint32(pktout, 0);
7723 ssh2_pkt_send(ssh, pktout);
32874aea 7724 }
7725 }
7726 break;
374330e2 7727 }
7728}
7729
7730/*
125105d1 7731 * Return a list of the special codes that make sense in this
7732 * protocol.
7733 */
7734static const struct telnet_special *ssh_get_specials(void *handle)
7735{
786ba75e 7736 static const struct telnet_special ssh1_ignore_special[] = {
7737 {"IGNORE message", TS_NOP}
7738 };
7739 static const struct telnet_special ssh2_transport_specials[] = {
62638676 7740 {"IGNORE message", TS_NOP},
9442dd57 7741 {"Repeat key exchange", TS_REKEY},
62638676 7742 };
7743 static const struct telnet_special ssh2_session_specials[] = {
6f2d0cde 7744 {NULL, TS_SEP},
7745 {"Break", TS_BRK},
786ba75e 7746 /* These are the signal names defined by draft-ietf-secsh-connect-23.
6f2d0cde 7747 * They include all the ISO C signals, but are a subset of the POSIX
7748 * required signals. */
7749 {"SIGINT (Interrupt)", TS_SIGINT},
7750 {"SIGTERM (Terminate)", TS_SIGTERM},
7751 {"SIGKILL (Kill)", TS_SIGKILL},
7752 {"SIGQUIT (Quit)", TS_SIGQUIT},
7753 {"SIGHUP (Hangup)", TS_SIGHUP},
7754 {"More signals", TS_SUBMENU},
7755 {"SIGABRT", TS_SIGABRT}, {"SIGALRM", TS_SIGALRM},
7756 {"SIGFPE", TS_SIGFPE}, {"SIGILL", TS_SIGILL},
7757 {"SIGPIPE", TS_SIGPIPE}, {"SIGSEGV", TS_SIGSEGV},
7758 {"SIGUSR1", TS_SIGUSR1}, {"SIGUSR2", TS_SIGUSR2},
7759 {NULL, TS_EXITMENU}
62638676 7760 };
7761 static const struct telnet_special specials_end[] = {
6f2d0cde 7762 {NULL, TS_EXITMENU}
62638676 7763 };
786ba75e 7764 /* XXX review this length for any changes: */
7765 static struct telnet_special ssh_specials[lenof(ssh2_transport_specials) +
62638676 7766 lenof(ssh2_session_specials) +
7767 lenof(specials_end)];
125105d1 7768 Ssh ssh = (Ssh) handle;
62638676 7769 int i = 0;
7770#define ADD_SPECIALS(name) \
7771 do { \
7772 assert((i + lenof(name)) <= lenof(ssh_specials)); \
7773 memcpy(&ssh_specials[i], name, sizeof name); \
7774 i += lenof(name); \
7775 } while(0)
125105d1 7776
7777 if (ssh->version == 1) {
62638676 7778 /* Don't bother offering IGNORE if we've decided the remote
7779 * won't cope with it, since we wouldn't bother sending it if
7780 * asked anyway. */
7781 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE))
786ba75e 7782 ADD_SPECIALS(ssh1_ignore_special);
125105d1 7783 } else if (ssh->version == 2) {
786ba75e 7784 ADD_SPECIALS(ssh2_transport_specials);
62638676 7785 if (ssh->mainchan)
7786 ADD_SPECIALS(ssh2_session_specials);
7787 } /* else we're not ready yet */
7788
7789 if (i) {
7790 ADD_SPECIALS(specials_end);
7791 return ssh_specials;
7792 } else {
125105d1 7793 return NULL;
62638676 7794 }
7795#undef ADD_SPECIALS
125105d1 7796}
7797
7798/*
6abbf9e3 7799 * Send Telnet special codes. TS_EOF is useful for `plink', so you
7800 * can send an EOF and collect resulting output (e.g. `plink
7801 * hostname sort').
374330e2 7802 */
51470298 7803static void ssh_special(void *handle, Telnet_Special code)
32874aea 7804{
51470298 7805 Ssh ssh = (Ssh) handle;
ff3187f6 7806 struct Packet *pktout;
51470298 7807
6abbf9e3 7808 if (code == TS_EOF) {
51470298 7809 if (ssh->state != SSH_STATE_SESSION) {
32874aea 7810 /*
7811 * Buffer the EOF in case we are pre-SESSION, so we can
7812 * send it as soon as we reach SESSION.
7813 */
7814 if (code == TS_EOF)
51470298 7815 ssh->eof_needed = TRUE;
32874aea 7816 return;
7817 }
51470298 7818 if (ssh->version == 1) {
7819 send_packet(ssh, SSH1_CMSG_EOF, PKT_END);
0ed48730 7820 } else if (ssh->mainchan) {
ff3187f6 7821 struct Packet *pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF);
7822 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7823 ssh2_pkt_send(ssh, pktout);
32874aea 7824 }
7825 logevent("Sent EOF message");
125105d1 7826 } else if (code == TS_PING || code == TS_NOP) {
51470298 7827 if (ssh->state == SSH_STATE_CLOSED
7828 || ssh->state == SSH_STATE_PREPACKET) return;
7829 if (ssh->version == 1) {
7830 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE))
7831 send_packet(ssh, SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
32874aea 7832 } else {
ff3187f6 7833 pktout = ssh2_pkt_init(SSH2_MSG_IGNORE);
7834 ssh2_pkt_addstring_start(pktout);
590f6a5f 7835 ssh2_pkt_send_noqueue(ssh, pktout);
32874aea 7836 }
9442dd57 7837 } else if (code == TS_REKEY) {
7838 if (!ssh->kex_in_progress && ssh->version == 2) {
f382c87d 7839 do_ssh2_transport(ssh, "at user request", -1, NULL);
9442dd57 7840 }
125105d1 7841 } else if (code == TS_BRK) {
7842 if (ssh->state == SSH_STATE_CLOSED
7843 || ssh->state == SSH_STATE_PREPACKET) return;
7844 if (ssh->version == 1) {
7845 logevent("Unable to send BREAK signal in SSH1");
0ed48730 7846 } else if (ssh->mainchan) {
ff3187f6 7847 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7848 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7849 ssh2_pkt_addstring(pktout, "break");
7850 ssh2_pkt_addbool(pktout, 0);
7851 ssh2_pkt_adduint32(pktout, 0); /* default break length */
7852 ssh2_pkt_send(ssh, pktout);
125105d1 7853 }
6abbf9e3 7854 } else {
6f2d0cde 7855 /* Is is a POSIX signal? */
7856 char *signame = NULL;
7857 if (code == TS_SIGABRT) signame = "ABRT";
7858 if (code == TS_SIGALRM) signame = "ALRM";
7859 if (code == TS_SIGFPE) signame = "FPE";
7860 if (code == TS_SIGHUP) signame = "HUP";
7861 if (code == TS_SIGILL) signame = "ILL";
7862 if (code == TS_SIGINT) signame = "INT";
7863 if (code == TS_SIGKILL) signame = "KILL";
7864 if (code == TS_SIGPIPE) signame = "PIPE";
7865 if (code == TS_SIGQUIT) signame = "QUIT";
7866 if (code == TS_SIGSEGV) signame = "SEGV";
7867 if (code == TS_SIGTERM) signame = "TERM";
7868 if (code == TS_SIGUSR1) signame = "USR1";
7869 if (code == TS_SIGUSR2) signame = "USR2";
7870 /* The SSH-2 protocol does in principle support arbitrary named
7871 * signals, including signame@domain, but we don't support those. */
7872 if (signame) {
7873 /* It's a signal. */
7874 if (ssh->version == 2 && ssh->mainchan) {
ff3187f6 7875 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7876 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7877 ssh2_pkt_addstring(pktout, "signal");
7878 ssh2_pkt_addbool(pktout, 0);
7879 ssh2_pkt_addstring(pktout, signame);
7880 ssh2_pkt_send(ssh, pktout);
6f2d0cde 7881 logeventf(ssh, "Sent signal SIG%s", signame);
7882 }
7883 } else {
7884 /* Never heard of it. Do nothing */
7885 }
6abbf9e3 7886 }
374330e2 7887}
7888
51470298 7889void *new_sock_channel(void *handle, Socket s)
d74d141c 7890{
51470298 7891 Ssh ssh = (Ssh) handle;
d74d141c 7892 struct ssh_channel *c;
3d88e64d 7893 c = snew(struct ssh_channel);
51470298 7894 c->ssh = ssh;
d74d141c 7895
7896 if (c) {
64d6ff88 7897 c->halfopen = TRUE;
51470298 7898 c->localid = alloc_channel_id(ssh);
d74d141c 7899 c->closes = 0;
bc240b21 7900 c->type = CHAN_SOCKDATA_DORMANT;/* identify channel type */
d74d141c 7901 c->u.pfd.s = s;
013dd8c0 7902 bufchain_init(&c->v.v2.outbuffer);
51470298 7903 add234(ssh->channels, c);
d74d141c 7904 }
7905 return c;
7906}
7907
5471d09a 7908/*
7909 * This is called when stdout/stderr (the entity to which
7910 * from_backend sends data) manages to clear some backlog.
7911 */
ae9ae89f 7912static void ssh_unthrottle(void *handle, int bufsize)
5471d09a 7913{
51470298 7914 Ssh ssh = (Ssh) handle;
7915 if (ssh->version == 1) {
7916 if (ssh->v1_stdout_throttling && bufsize < SSH1_BUFFER_LIMIT) {
7917 ssh->v1_stdout_throttling = 0;
7918 ssh1_throttle(ssh, -1);
5471d09a 7919 }
7920 } else {
51470298 7921 if (ssh->mainchan && ssh->mainchan->closes == 0)
7922 ssh2_set_window(ssh->mainchan, OUR_V2_WINSIZE - bufsize);
5471d09a 7923 }
7924}
7925
6b78788a 7926void ssh_send_port_open(void *channel, char *hostname, int port, char *org)
d74d141c 7927{
7928 struct ssh_channel *c = (struct ssh_channel *)channel;
6b78788a 7929 Ssh ssh = c->ssh;
ff3187f6 7930 struct Packet *pktout;
d74d141c 7931
57356d63 7932 logeventf(ssh, "Opening forwarded connection to %s:%d", hostname, port);
d74d141c 7933
51470298 7934 if (ssh->version == 1) {
7935 send_packet(ssh, SSH1_MSG_PORT_OPEN,
bc240b21 7936 PKT_INT, c->localid,
7937 PKT_STR, hostname,
7938 PKT_INT, port,
31fb1866 7939 /* PKT_STR, <org:orgport>, */
bc240b21 7940 PKT_END);
7941 } else {
ff3187f6 7942 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
7943 ssh2_pkt_addstring(pktout, "direct-tcpip");
7944 ssh2_pkt_adduint32(pktout, c->localid);
5471d09a 7945 c->v.v2.locwindow = OUR_V2_WINSIZE;
ff3187f6 7946 ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);/* our window size */
954d5c5a 7947 ssh2_pkt_adduint32(pktout, OUR_V2_MAXPKT); /* our max pkt size */
ff3187f6 7948 ssh2_pkt_addstring(pktout, hostname);
7949 ssh2_pkt_adduint32(pktout, port);
bc240b21 7950 /*
7951 * We make up values for the originator data; partly it's
7952 * too much hassle to keep track, and partly I'm not
7953 * convinced the server should be told details like that
7954 * about my local network configuration.
7955 */
ff3187f6 7956 ssh2_pkt_addstring(pktout, "client-side-connection");
7957 ssh2_pkt_adduint32(pktout, 0);
7958 ssh2_pkt_send(ssh, pktout);
bc240b21 7959 }
d74d141c 7960}
7961
51470298 7962static Socket ssh_socket(void *handle)
32874aea 7963{
51470298 7964 Ssh ssh = (Ssh) handle;
7965 return ssh->s;
32874aea 7966}
8ccc75b0 7967
51470298 7968static int ssh_sendok(void *handle)
32874aea 7969{
51470298 7970 Ssh ssh = (Ssh) handle;
7971 return ssh->send_ok;
32874aea 7972}
fb09bf1c 7973
51470298 7974static int ssh_ldisc(void *handle, int option)
32874aea 7975{
51470298 7976 Ssh ssh = (Ssh) handle;
32874aea 7977 if (option == LD_ECHO)
51470298 7978 return ssh->echoing;
32874aea 7979 if (option == LD_EDIT)
51470298 7980 return ssh->editing;
0965bee0 7981 return FALSE;
7982}
7983
b9d7bcad 7984static void ssh_provide_ldisc(void *handle, void *ldisc)
7985{
7986 Ssh ssh = (Ssh) handle;
7987 ssh->ldisc = ldisc;
7988}
7989
a8327734 7990static void ssh_provide_logctx(void *handle, void *logctx)
7991{
7992 Ssh ssh = (Ssh) handle;
7993 ssh->logctx = logctx;
7994}
7995
51470298 7996static int ssh_return_exitcode(void *handle)
7997{
7998 Ssh ssh = (Ssh) handle;
3bb2f322 7999 if (ssh->s != NULL)
8000 return -1;
8001 else
8002 return (ssh->exitcode >= 0 ? ssh->exitcode : 0);
51470298 8003}
8004
8005/*
f89c3294 8006 * cfg_info for SSH is the currently running version of the
8007 * protocol. (1 for 1; 2 for 2; 0 for not-decided-yet.)
8008 */
8009static int ssh_cfg_info(void *handle)
8010{
8011 Ssh ssh = (Ssh) handle;
8012 return ssh->version;
8013}
8014
8015/*
51470298 8016 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
8017 * that fails. This variable is the means by which scp.c can reach
8018 * into the SSH code and find out which one it got.
8019 */
8020extern int ssh_fallback_cmd(void *handle)
d8d6c7e5 8021{
51470298 8022 Ssh ssh = (Ssh) handle;
8023 return ssh->fallback_cmd;
d8d6c7e5 8024}
8025
374330e2 8026Backend ssh_backend = {
8027 ssh_init,
fabd1805 8028 ssh_free,
86916870 8029 ssh_reconfig,
374330e2 8030 ssh_send,
5471d09a 8031 ssh_sendbuffer,
374330e2 8032 ssh_size,
4017be6d 8033 ssh_special,
125105d1 8034 ssh_get_specials,
8ccc75b0 8035 ssh_socket,
d8d6c7e5 8036 ssh_return_exitcode,
97db3be4 8037 ssh_sendok,
0965bee0 8038 ssh_ldisc,
b9d7bcad 8039 ssh_provide_ldisc,
a8327734 8040 ssh_provide_logctx,
5471d09a 8041 ssh_unthrottle,
f89c3294 8042 ssh_cfg_info,
97db3be4 8043 22
bc240b21 8044};
Local modifications for Simon Tatham's `PuTTY' SSH client and terminal emulator