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Make our SSH2 maximum packet size into a constant, since it's used in several
[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;
0357890f 439 /*
440 * In SSH1, this value contains four bits:
441 *
442 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
443 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
444 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
445 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
446 *
447 * A channel is completely finished with when all four bits are set.
448 */
dacbd0e8 449 int closes;
5471d09a 450 union {
451 struct ssh1_data_channel {
452 int throttling;
453 } v1;
454 struct ssh2_data_channel {
455 bufchain outbuffer;
456 unsigned remwindow, remmaxpkt;
457 unsigned locwindow;
458 } v2;
459 } v;
dacbd0e8 460 union {
32874aea 461 struct ssh_agent_channel {
462 unsigned char *message;
463 unsigned char msglen[4];
a03c9f9c 464 unsigned lensofar, totallen;
32874aea 465 } a;
466 struct ssh_x11_channel {
467 Socket s;
468 } x11;
d74d141c 469 struct ssh_pfd_channel {
470 Socket s;
471 } pfd;
dacbd0e8 472 } u;
473};
57476f6b 474
d74d141c 475/*
bc240b21 476 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
477 * 2 use this structure in different ways, reflecting SSH 2's
478 * altogether saner approach to port forwarding.
479 *
480 * In SSH 1, you arrange a remote forwarding by sending the server
481 * the remote port number, and the local destination host:port.
482 * When a connection comes in, the server sends you back that
483 * host:port pair, and you connect to it. This is a ready-made
484 * security hole if you're not on the ball: a malicious server
485 * could send you back _any_ host:port pair, so if you trustingly
486 * connect to the address it gives you then you've just opened the
487 * entire inside of your corporate network just by connecting
488 * through it to a dodgy SSH server. Hence, we must store a list of
489 * host:port pairs we _are_ trying to forward to, and reject a
490 * connection request from the server if it's not in the list.
491 *
492 * In SSH 2, each side of the connection minds its own business and
493 * doesn't send unnecessary information to the other. You arrange a
494 * remote forwarding by sending the server just the remote port
495 * number. When a connection comes in, the server tells you which
496 * of its ports was connected to; and _you_ have to remember what
497 * local host:port pair went with that port number.
498 *
06fadff5 499 * Hence, in SSH 1 this structure is indexed by destination
500 * host:port pair, whereas in SSH 2 it is indexed by source port.
d74d141c 501 */
fda2feb1 502struct ssh_portfwd; /* forward declaration */
503
d74d141c 504struct ssh_rportfwd {
bc240b21 505 unsigned sport, dport;
506 char dhost[256];
06fadff5 507 char *sportdesc;
fda2feb1 508 struct ssh_portfwd *pfrec;
d74d141c 509};
fda2feb1 510#define free_rportfwd(pf) ( \
511 ((pf) ? (sfree((pf)->sportdesc)) : (void)0 ), sfree(pf) )
512
513/*
514 * Separately to the rportfwd tree (which is for looking up port
515 * open requests from the server), a tree of _these_ structures is
516 * used to keep track of all the currently open port forwardings,
517 * so that we can reconfigure in mid-session if the user requests
518 * it.
519 */
520struct ssh_portfwd {
84328ddb 521 enum { DESTROY, KEEP, CREATE } status;
fda2feb1 522 int type;
523 unsigned sport, dport;
524 char *saddr, *daddr;
3fe92132 525 char *sserv, *dserv;
fda2feb1 526 struct ssh_rportfwd *remote;
05581745 527 int addressfamily;
fda2feb1 528 void *local;
529};
530#define free_portfwd(pf) ( \
3fe92132 531 ((pf) ? (sfree((pf)->saddr), sfree((pf)->daddr), \
532 sfree((pf)->sserv), sfree((pf)->dserv)) : (void)0 ), sfree(pf) )
d74d141c 533
57476f6b 534struct Packet {
535 long length;
536 int type;
b09eaa88 537 unsigned long sequence;
57476f6b 538 unsigned char *data;
539 unsigned char *body;
540 long savedpos;
541 long maxlen;
9442dd57 542 long encrypted_len; /* for SSH2 total-size counting */
ff3187f6 543
544 /*
545 * State associated with packet logging
546 */
547 int logmode;
548 int nblanks;
549 struct logblank_t *blanks;
57476f6b 550};
551
ff3187f6 552static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen,
553 struct Packet *pktin);
554static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen,
555 struct Packet *pktin);
b09eaa88 556static void ssh1_protocol_setup(Ssh ssh);
557static void ssh2_protocol_setup(Ssh ssh);
51470298 558static void ssh_size(void *handle, int width, int height);
559static void ssh_special(void *handle, Telnet_Special);
5471d09a 560static int ssh2_try_send(struct ssh_channel *c);
51470298 561static void ssh2_add_channel_data(struct ssh_channel *c, char *buf, int len);
562static void ssh_throttle_all(Ssh ssh, int enable, int bufsize);
5471d09a 563static void ssh2_set_window(struct ssh_channel *c, unsigned newwin);
51470298 564static int ssh_sendbuffer(void *handle);
ac934965 565static int ssh_do_close(Ssh ssh, int notify_exit);
ff3187f6 566static unsigned long ssh_pkt_getuint32(struct Packet *pkt);
567static int ssh2_pkt_getbool(struct Packet *pkt);
568static void ssh_pkt_getstring(struct Packet *pkt, char **p, int *length);
9442dd57 569static void ssh2_timer(void *ctx, long now);
570static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen,
571 struct Packet *pktin);
57476f6b 572
51470298 573struct rdpkt1_state_tag {
57476f6b 574 long len, pad, biglen, to_read;
575 unsigned long realcrc, gotcrc;
576 unsigned char *p;
577 int i;
578 int chunk;
ff3187f6 579 struct Packet *pktin;
51470298 580};
57476f6b 581
51470298 582struct rdpkt2_state_tag {
960e736a 583 long len, pad, payload, packetlen, maclen;
584 int i;
585 int cipherblk;
586 unsigned long incoming_sequence;
ff3187f6 587 struct Packet *pktin;
51470298 588};
589
b09eaa88 590typedef void (*handler_fn_t)(Ssh ssh, struct Packet *pktin);
06fadff5 591typedef void (*chandler_fn_t)(Ssh ssh, struct Packet *pktin, void *ctx);
592
593struct queued_handler;
594struct queued_handler {
595 int msg1, msg2;
596 chandler_fn_t handler;
597 void *ctx;
598 struct queued_handler *next;
599};
b09eaa88 600
51470298 601struct ssh_tag {
602 const struct plug_function_table *fn;
603 /* the above field _must_ be first in the structure */
604
605 SHA_State exhash, exhashbase;
606
607 Socket s;
608
b9d7bcad 609 void *ldisc;
a8327734 610 void *logctx;
b9d7bcad 611
51470298 612 unsigned char session_key[32];
613 int v1_compressing;
614 int v1_remote_protoflags;
615 int v1_local_protoflags;
616 int agentfwd_enabled;
617 int X11_fwd_enabled;
618 int remote_bugs;
619 const struct ssh_cipher *cipher;
371e569c 620 void *v1_cipher_ctx;
0183b242 621 void *crcda_ctx;
51470298 622 const struct ssh2_cipher *cscipher, *sccipher;
371e569c 623 void *cs_cipher_ctx, *sc_cipher_ctx;
51470298 624 const struct ssh_mac *csmac, *scmac;
e0e1a00d 625 void *cs_mac_ctx, *sc_mac_ctx;
51470298 626 const struct ssh_compress *cscomp, *sccomp;
5366aed8 627 void *cs_comp_ctx, *sc_comp_ctx;
51470298 628 const struct ssh_kex *kex;
629 const struct ssh_signkey *hostkey;
630 unsigned char v2_session_id[20];
27cd7fc2 631 void *kex_ctx;
51470298 632
633 char *savedhost;
634 int savedport;
635 int send_ok;
636 int echoing, editing;
637
638 void *frontend;
639
db219738 640 int ospeed, ispeed; /* temporaries */
51470298 641 int term_width, term_height;
642
643 tree234 *channels; /* indexed by local id */
644 struct ssh_channel *mainchan; /* primary session channel */
645 int exitcode;
ac934965 646 int close_expected;
51470298 647
fda2feb1 648 tree234 *rportfwds, *portfwds;
51470298 649
650 enum {
651 SSH_STATE_PREPACKET,
652 SSH_STATE_BEFORE_SIZE,
653 SSH_STATE_INTERMED,
654 SSH_STATE_SESSION,
655 SSH_STATE_CLOSED
656 } state;
657
658 int size_needed, eof_needed;
659
590f6a5f 660 struct Packet **queue;
661 int queuelen, queuesize;
662 int queueing;
51470298 663 unsigned char *deferred_send_data;
664 int deferred_len, deferred_size;
665
666 /*
667 * Gross hack: pscp will try to start SFTP but fall back to
668 * scp1 if that fails. This variable is the means by which
669 * scp.c can reach into the SSH code and find out which one it
670 * got.
671 */
672 int fallback_cmd;
673
674 /*
675 * Used for username and password input.
676 */
677 char *userpass_input_buffer;
678 int userpass_input_buflen;
679 int userpass_input_bufpos;
680 int userpass_input_echo;
681
51470298 682 int pkt_ctx;
683
302121de 684 void *x11auth;
685
51470298 686 int version;
687 int v1_throttle_count;
688 int overall_bufsize;
689 int throttled_all;
690 int v1_stdout_throttling;
691 int v2_outgoing_sequence;
692
693 int ssh1_rdpkt_crstate;
694 int ssh2_rdpkt_crstate;
695 int do_ssh_init_crstate;
696 int ssh_gotdata_crstate;
51470298 697 int do_ssh1_login_crstate;
b09eaa88 698 int do_ssh1_connection_crstate;
51470298 699 int do_ssh2_transport_crstate;
700 int do_ssh2_authconn_crstate;
701
702 void *do_ssh_init_state;
703 void *do_ssh1_login_state;
704 void *do_ssh2_transport_state;
705 void *do_ssh2_authconn_state;
706
707 struct rdpkt1_state_tag rdpkt1_state;
708 struct rdpkt2_state_tag rdpkt2_state;
709
b09eaa88 710 /* ssh1 and ssh2 use this for different things, but both use it */
711 int protocol_initial_phase_done;
712
ff3187f6 713 void (*protocol) (Ssh ssh, unsigned char *in, int inlen,
714 struct Packet *pkt);
715 struct Packet *(*s_rdpkt) (Ssh ssh, unsigned char **data, int *datalen);
86916870 716
717 /*
718 * We maintain a full _copy_ of a Config structure here, not
719 * merely a pointer to it. That way, when we're passed a new
720 * one for reconfiguration, we can check the differences and
721 * potentially reconfigure port forwardings etc in mid-session.
722 */
723 Config cfg;
839f10db 724
725 /*
726 * Used to transfer data back from async agent callbacks.
727 */
728 void *agent_response;
729 int agent_response_len;
b09eaa88 730
731 /*
732 * Dispatch table for packet types that we may have to deal
733 * with at any time.
734 */
735 handler_fn_t packet_dispatch[256];
39934deb 736
737 /*
06fadff5 738 * Queues of one-off handler functions for success/failure
739 * indications from a request.
740 */
741 struct queued_handler *qhead, *qtail;
742
743 /*
39934deb 744 * This module deals with sending keepalives.
745 */
746 Pinger pinger;
9442dd57 747
748 /*
749 * Track incoming and outgoing data sizes and time, for
750 * size-based rekeys.
751 */
752 unsigned long incoming_data_size, outgoing_data_size, deferred_data_size;
d57f70af 753 unsigned long max_data_size;
9442dd57 754 int kex_in_progress;
e6c1536e 755 long next_rekey, last_rekey;
e13bba36 756 char *deferred_rekey_reason; /* points to STATIC string; don't free */
51470298 757};
960e736a 758
382908ad 759#define logevent(s) logevent(ssh->frontend, s)
a8327734 760
761/* logevent, only printf-formatted. */
cbe2d68f 762static void logeventf(Ssh ssh, const char *fmt, ...)
a8327734 763{
764 va_list ap;
57356d63 765 char *buf;
a8327734 766
767 va_start(ap, fmt);
57356d63 768 buf = dupvprintf(fmt, ap);
a8327734 769 va_end(ap);
57356d63 770 logevent(buf);
57356d63 771 sfree(buf);
a8327734 772}
773
6b5cf8b4 774#define bombout(msg) \
775 do { \
776 char *text = dupprintf msg; \
ac934965 777 ssh_do_close(ssh, FALSE); \
6b5cf8b4 778 logevent(text); \
779 connection_fatal(ssh->frontend, "%s", text); \
780 sfree(text); \
781 } while (0)
a8327734 782
9a10ecf4 783/* Functions to leave bits out of the SSH packet log file. */
784
ff3187f6 785static void dont_log_password(Ssh ssh, struct Packet *pkt, int blanktype)
9a10ecf4 786{
787 if (ssh->cfg.logomitpass)
ff3187f6 788 pkt->logmode = blanktype;
9a10ecf4 789}
790
ff3187f6 791static void dont_log_data(Ssh ssh, struct Packet *pkt, int blanktype)
9a10ecf4 792{
793 if (ssh->cfg.logomitdata)
ff3187f6 794 pkt->logmode = blanktype;
9a10ecf4 795}
796
ff3187f6 797static void end_log_omission(Ssh ssh, struct Packet *pkt)
9a10ecf4 798{
ff3187f6 799 pkt->logmode = PKTLOG_EMIT;
9a10ecf4 800}
801
32874aea 802static int ssh_channelcmp(void *av, void *bv)
803{
804 struct ssh_channel *a = (struct ssh_channel *) av;
805 struct ssh_channel *b = (struct ssh_channel *) bv;
806 if (a->localid < b->localid)
807 return -1;
808 if (a->localid > b->localid)
809 return +1;
dacbd0e8 810 return 0;
811}
32874aea 812static int ssh_channelfind(void *av, void *bv)
813{
814 unsigned *a = (unsigned *) av;
815 struct ssh_channel *b = (struct ssh_channel *) bv;
816 if (*a < b->localid)
817 return -1;
818 if (*a > b->localid)
819 return +1;
dacbd0e8 820 return 0;
821}
822
bc240b21 823static int ssh_rportcmp_ssh1(void *av, void *bv)
d74d141c 824{
825 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
826 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
827 int i;
bc240b21 828 if ( (i = strcmp(a->dhost, b->dhost)) != 0)
d74d141c 829 return i < 0 ? -1 : +1;
bc240b21 830 if (a->dport > b->dport)
831 return +1;
832 if (a->dport < b->dport)
833 return -1;
834 return 0;
835}
836
837static int ssh_rportcmp_ssh2(void *av, void *bv)
838{
839 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
840 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
cdcbdf3b 841
bc240b21 842 if (a->sport > b->sport)
d74d141c 843 return +1;
bc240b21 844 if (a->sport < b->sport)
845 return -1;
d74d141c 846 return 0;
847}
848
fda2feb1 849/*
850 * Special form of strcmp which can cope with NULL inputs. NULL is
851 * defined to sort before even the empty string.
852 */
853static int nullstrcmp(const char *a, const char *b)
854{
855 if (a == NULL && b == NULL)
856 return 0;
857 if (a == NULL)
858 return -1;
859 if (b == NULL)
860 return +1;
861 return strcmp(a, b);
862}
863
864static int ssh_portcmp(void *av, void *bv)
865{
866 struct ssh_portfwd *a = (struct ssh_portfwd *) av;
867 struct ssh_portfwd *b = (struct ssh_portfwd *) bv;
868 int i;
869 if (a->type > b->type)
870 return +1;
871 if (a->type < b->type)
872 return -1;
84328ddb 873 if (a->addressfamily > b->addressfamily)
874 return +1;
875 if (a->addressfamily < b->addressfamily)
876 return -1;
fda2feb1 877 if ( (i = nullstrcmp(a->saddr, b->saddr)) != 0)
878 return i < 0 ? -1 : +1;
879 if (a->sport > b->sport)
880 return +1;
881 if (a->sport < b->sport)
882 return -1;
883 if (a->type != 'D') {
884 if ( (i = nullstrcmp(a->daddr, b->daddr)) != 0)
885 return i < 0 ? -1 : +1;
886 if (a->dport > b->dport)
887 return +1;
888 if (a->dport < b->dport)
889 return -1;
890 }
891 return 0;
892}
893
51470298 894static int alloc_channel_id(Ssh ssh)
32874aea 895{
260f3dec 896 const unsigned CHANNEL_NUMBER_OFFSET = 256;
897 unsigned low, high, mid;
d2371c81 898 int tsize;
899 struct ssh_channel *c;
900
901 /*
902 * First-fit allocation of channel numbers: always pick the
903 * lowest unused one. To do this, binary-search using the
904 * counted B-tree to find the largest channel ID which is in a
905 * contiguous sequence from the beginning. (Precisely
906 * everything in that sequence must have ID equal to its tree
907 * index plus CHANNEL_NUMBER_OFFSET.)
908 */
51470298 909 tsize = count234(ssh->channels);
d2371c81 910
32874aea 911 low = -1;
912 high = tsize;
d2371c81 913 while (high - low > 1) {
914 mid = (high + low) / 2;
51470298 915 c = index234(ssh->channels, mid);
d2371c81 916 if (c->localid == mid + CHANNEL_NUMBER_OFFSET)
917 low = mid; /* this one is fine */
918 else
919 high = mid; /* this one is past it */
920 }
921 /*
922 * Now low points to either -1, or the tree index of the
923 * largest ID in the initial sequence.
924 */
925 {
926 unsigned i = low + 1 + CHANNEL_NUMBER_OFFSET;
51470298 927 assert(NULL == find234(ssh->channels, &i, ssh_channelfind));
d2371c81 928 }
929 return low + 1 + CHANNEL_NUMBER_OFFSET;
930}
931
9fab77dc 932static void c_write(Ssh ssh, const char *buf, int len)
32874aea 933{
67779be7 934 if ((flags & FLAG_STDERR)) {
32874aea 935 int i;
936 for (i = 0; i < len; i++)
937 if (buf[i] != '\r')
938 fputc(buf[i], stderr);
fb09bf1c 939 return;
940 }
51470298 941 from_backend(ssh->frontend, 1, buf, len);
3bdaf79d 942}
943
9fab77dc 944static void c_write_untrusted(Ssh ssh, const char *buf, int len)
32874aea 945{
a209e957 946 int i;
947 for (i = 0; i < len; i++) {
32874aea 948 if (buf[i] == '\n')
51470298 949 c_write(ssh, "\r\n", 2);
32874aea 950 else if ((buf[i] & 0x60) || (buf[i] == '\r'))
51470298 951 c_write(ssh, buf + i, 1);
a209e957 952 }
953}
954
9fab77dc 955static void c_write_str(Ssh ssh, const char *buf)
32874aea 956{
51470298 957 c_write(ssh, buf, strlen(buf));
1408a877 958}
959
ff3187f6 960static void ssh_free_packet(struct Packet *pkt)
961{
962 sfree(pkt->data);
963 sfree(pkt);
964}
965static struct Packet *ssh_new_packet(void)
966{
967 struct Packet *pkt = snew(struct Packet);
968
969 pkt->data = NULL;
970 pkt->maxlen = 0;
971 pkt->logmode = PKTLOG_EMIT;
972 pkt->nblanks = 0;
973 pkt->blanks = NULL;
974
975 return pkt;
976}
977
fb09bf1c 978/*
979 * Collect incoming data in the incoming packet buffer.
e5574168 980 * Decipher and verify the packet when it is completely read.
981 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
fb09bf1c 982 * Update the *data and *datalen variables.
ff3187f6 983 * Return a Packet structure when a packet is completed.
fb09bf1c 984 */
ff3187f6 985static struct Packet *ssh1_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
fb09bf1c 986{
51470298 987 struct rdpkt1_state_tag *st = &ssh->rdpkt1_state;
374330e2 988
51470298 989 crBegin(ssh->ssh1_rdpkt_crstate);
374330e2 990
ff3187f6 991 st->pktin = ssh_new_packet();
992
993 st->pktin->type = 0;
994 st->pktin->length = 0;
374330e2 995
57476f6b 996 for (st->i = st->len = 0; st->i < 4; st->i++) {
fb09bf1c 997 while ((*datalen) == 0)
ff3187f6 998 crReturn(NULL);
57476f6b 999 st->len = (st->len << 8) + **data;
fb09bf1c 1000 (*data)++, (*datalen)--;
1001 }
374330e2 1002
57476f6b 1003 st->pad = 8 - (st->len % 8);
1004 st->biglen = st->len + st->pad;
ff3187f6 1005 st->pktin->length = st->len - 5;
fb09bf1c 1006
ae0500e5 1007 if (st->biglen < 0) {
1008 bombout(("Extremely large packet length from server suggests"
1009 " data stream corruption"));
ff3187f6 1010 ssh_free_packet(st->pktin);
1011 crStop(NULL);
ae0500e5 1012 }
1013
ff3187f6 1014 st->pktin->maxlen = st->biglen;
1015 st->pktin->data = snewn(st->biglen + APIEXTRA, unsigned char);
374330e2 1016
57476f6b 1017 st->to_read = st->biglen;
ff3187f6 1018 st->p = st->pktin->data;
57476f6b 1019 while (st->to_read > 0) {
32874aea 1020 st->chunk = st->to_read;
fb09bf1c 1021 while ((*datalen) == 0)
ff3187f6 1022 crReturn(NULL);
57476f6b 1023 if (st->chunk > (*datalen))
1024 st->chunk = (*datalen);
1025 memcpy(st->p, *data, st->chunk);
1026 *data += st->chunk;
1027 *datalen -= st->chunk;
1028 st->p += st->chunk;
1029 st->to_read -= st->chunk;
fb09bf1c 1030 }
374330e2 1031
ff3187f6 1032 if (ssh->cipher && detect_attack(ssh->crcda_ctx, st->pktin->data,
0183b242 1033 st->biglen, NULL)) {
6b5cf8b4 1034 bombout(("Network attack (CRC compensation) detected!"));
ff3187f6 1035 ssh_free_packet(st->pktin);
1036 crStop(NULL);
9a3a93a5 1037 }
1038
51470298 1039 if (ssh->cipher)
ff3187f6 1040 ssh->cipher->decrypt(ssh->v1_cipher_ctx, st->pktin->data, st->biglen);
374330e2 1041
ff3187f6 1042 st->realcrc = crc32_compute(st->pktin->data, st->biglen - 4);
1043 st->gotcrc = GET_32BIT(st->pktin->data + st->biglen - 4);
57476f6b 1044 if (st->gotcrc != st->realcrc) {
6b5cf8b4 1045 bombout(("Incorrect CRC received on packet"));
ff3187f6 1046 ssh_free_packet(st->pktin);
1047 crStop(NULL);
fb09bf1c 1048 }
572f871e 1049
ff3187f6 1050 st->pktin->body = st->pktin->data + st->pad + 1;
1051 st->pktin->savedpos = 0;
4ba9b64b 1052
51470298 1053 if (ssh->v1_compressing) {
4ba9b64b 1054 unsigned char *decompblk;
1055 int decomplen;
36b8d9bb 1056 if (!zlib_decompress_block(ssh->sc_comp_ctx,
ff3187f6 1057 st->pktin->body - 1, st->pktin->length + 1,
36b8d9bb 1058 &decompblk, &decomplen)) {
1059 bombout(("Zlib decompression encountered invalid data"));
ff3187f6 1060 ssh_free_packet(st->pktin);
1061 crStop(NULL);
36b8d9bb 1062 }
4ba9b64b 1063
ff3187f6 1064 if (st->pktin->maxlen < st->pad + decomplen) {
1065 st->pktin->maxlen = st->pad + decomplen;
1066 st->pktin->data = sresize(st->pktin->data,
1067 st->pktin->maxlen + APIEXTRA,
3d88e64d 1068 unsigned char);
ff3187f6 1069 st->pktin->body = st->pktin->data + st->pad + 1;
4ba9b64b 1070 }
1071
ff3187f6 1072 memcpy(st->pktin->body - 1, decompblk, decomplen);
dcbde236 1073 sfree(decompblk);
ff3187f6 1074 st->pktin->length = decomplen - 1;
4ba9b64b 1075 }
1076
ff3187f6 1077 st->pktin->type = st->pktin->body[-1];
00db133f 1078
9a10ecf4 1079 /*
1080 * Log incoming packet, possibly omitting sensitive fields.
1081 */
1082 if (ssh->logctx) {
1083 int nblanks = 0;
1084 struct logblank_t blank;
1085 if (ssh->cfg.logomitdata) {
1086 int do_blank = FALSE, blank_prefix = 0;
1087 /* "Session data" packets - omit the data field */
ff3187f6 1088 if ((st->pktin->type == SSH1_SMSG_STDOUT_DATA) ||
1089 (st->pktin->type == SSH1_SMSG_STDERR_DATA)) {
9a10ecf4 1090 do_blank = TRUE; blank_prefix = 0;
ff3187f6 1091 } else if (st->pktin->type == SSH1_MSG_CHANNEL_DATA) {
9a10ecf4 1092 do_blank = TRUE; blank_prefix = 4;
1093 }
1094 if (do_blank) {
1095 blank.offset = blank_prefix;
ff3187f6 1096 blank.len = st->pktin->length;
9a10ecf4 1097 blank.type = PKTLOG_OMIT;
1098 nblanks = 1;
1099 }
1100 }
a8327734 1101 log_packet(ssh->logctx,
ff3187f6 1102 PKT_INCOMING, st->pktin->type,
1103 ssh1_pkt_type(st->pktin->type),
1104 st->pktin->body, st->pktin->length,
9a10ecf4 1105 nblanks, &blank);
1106 }
00db133f 1107
ff3187f6 1108 crFinish(st->pktin);
fb09bf1c 1109}
1110
ff3187f6 1111static struct Packet *ssh2_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
e5574168 1112{
51470298 1113 struct rdpkt2_state_tag *st = &ssh->rdpkt2_state;
e5574168 1114
51470298 1115 crBegin(ssh->ssh2_rdpkt_crstate);
e5574168 1116
ff3187f6 1117 st->pktin = ssh_new_packet();
1118
1119 st->pktin->type = 0;
1120 st->pktin->length = 0;
51470298 1121 if (ssh->sccipher)
1122 st->cipherblk = ssh->sccipher->blksize;
e5574168 1123 else
32874aea 1124 st->cipherblk = 8;
960e736a 1125 if (st->cipherblk < 8)
32874aea 1126 st->cipherblk = 8;
960e736a 1127
ff3187f6 1128 st->pktin->data = snewn(st->cipherblk + APIEXTRA, unsigned char);
e5574168 1129
1130 /*
1131 * Acquire and decrypt the first block of the packet. This will
1132 * contain the length and padding details.
1133 */
32874aea 1134 for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) {
e5574168 1135 while ((*datalen) == 0)
ff3187f6 1136 crReturn(NULL);
1137 st->pktin->data[st->i] = *(*data)++;
32874aea 1138 (*datalen)--;
e5574168 1139 }
4252c9cc 1140
51470298 1141 if (ssh->sccipher)
371e569c 1142 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
ff3187f6 1143 st->pktin->data, st->cipherblk);
e5574168 1144
1145 /*
1146 * Now get the length and padding figures.
1147 */
ff3187f6 1148 st->len = GET_32BIT(st->pktin->data);
1149 st->pad = st->pktin->data[4];
e5574168 1150
1151 /*
717dc483 1152 * _Completely_ silly lengths should be stomped on before they
1153 * do us any more damage.
1154 */
1155 if (st->len < 0 || st->pad < 0 || st->len + st->pad < 0) {
6b5cf8b4 1156 bombout(("Incoming packet was garbled on decryption"));
ff3187f6 1157 ssh_free_packet(st->pktin);
1158 crStop(NULL);
717dc483 1159 }
1160
1161 /*
e5574168 1162 * This enables us to deduce the payload length.
1163 */
960e736a 1164 st->payload = st->len - st->pad - 1;
e5574168 1165
ff3187f6 1166 st->pktin->length = st->payload + 5;
e5574168 1167
1168 /*
1169 * So now we can work out the total packet length.
1170 */
960e736a 1171 st->packetlen = st->len + 4;
51470298 1172 st->maclen = ssh->scmac ? ssh->scmac->len : 0;
e5574168 1173
1174 /*
ff3187f6 1175 * Allocate memory for the rest of the packet.
e5574168 1176 */
ff3187f6 1177 st->pktin->maxlen = st->packetlen + st->maclen;
1178 st->pktin->data = sresize(st->pktin->data,
1179 st->pktin->maxlen + APIEXTRA,
1180 unsigned char);
e5574168 1181
1182 /*
1183 * Read and decrypt the remainder of the packet.
1184 */
32874aea 1185 for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen;
1186 st->i++) {
e5574168 1187 while ((*datalen) == 0)
ff3187f6 1188 crReturn(NULL);
1189 st->pktin->data[st->i] = *(*data)++;
32874aea 1190 (*datalen)--;
e5574168 1191 }
1192 /* Decrypt everything _except_ the MAC. */
51470298 1193 if (ssh->sccipher)
371e569c 1194 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
ff3187f6 1195 st->pktin->data + st->cipherblk,
51470298 1196 st->packetlen - st->cipherblk);
e5574168 1197
9442dd57 1198 st->pktin->encrypted_len = st->packetlen;
1199
e5574168 1200 /*
1201 * Check the MAC.
1202 */
51470298 1203 if (ssh->scmac
ff3187f6 1204 && !ssh->scmac->verify(ssh->sc_mac_ctx, st->pktin->data, st->len + 4,
51470298 1205 st->incoming_sequence)) {
6b5cf8b4 1206 bombout(("Incorrect MAC received on packet"));
ff3187f6 1207 ssh_free_packet(st->pktin);
1208 crStop(NULL);
8d5de777 1209 }
b09eaa88 1210
1211 st->pktin->sequence = st->incoming_sequence++;
e5574168 1212
4ba9b64b 1213 /*
1214 * Decompress packet payload.
1215 */
1216 {
1217 unsigned char *newpayload;
1218 int newlen;
51470298 1219 if (ssh->sccomp &&
5366aed8 1220 ssh->sccomp->decompress(ssh->sc_comp_ctx,
ff3187f6 1221 st->pktin->data + 5, st->pktin->length - 5,
51470298 1222 &newpayload, &newlen)) {
ff3187f6 1223 if (st->pktin->maxlen < newlen + 5) {
1224 st->pktin->maxlen = newlen + 5;
1225 st->pktin->data = sresize(st->pktin->data,
1226 st->pktin->maxlen + APIEXTRA,
3d88e64d 1227 unsigned char);
4ba9b64b 1228 }
ff3187f6 1229 st->pktin->length = 5 + newlen;
1230 memcpy(st->pktin->data + 5, newpayload, newlen);
dcbde236 1231 sfree(newpayload);
4ba9b64b 1232 }
1233 }
1234
ff3187f6 1235 st->pktin->savedpos = 6;
1236 st->pktin->body = st->pktin->data;
1237 st->pktin->type = st->pktin->data[5];
e5574168 1238
9a10ecf4 1239 /*
1240 * Log incoming packet, possibly omitting sensitive fields.
1241 */
1242 if (ssh->logctx) {
1243 int nblanks = 0;
1244 struct logblank_t blank;
1245 if (ssh->cfg.logomitdata) {
1246 int do_blank = FALSE, blank_prefix = 0;
1247 /* "Session data" packets - omit the data field */
ff3187f6 1248 if (st->pktin->type == SSH2_MSG_CHANNEL_DATA) {
9a10ecf4 1249 do_blank = TRUE; blank_prefix = 4;
ff3187f6 1250 } else if (st->pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
9a10ecf4 1251 do_blank = TRUE; blank_prefix = 8;
1252 }
1253 if (do_blank) {
1254 blank.offset = blank_prefix;
ff3187f6 1255 blank.len = (st->pktin->length-6) - blank_prefix;
9a10ecf4 1256 blank.type = PKTLOG_OMIT;
1257 nblanks = 1;
1258 }
1259 }
ff3187f6 1260 log_packet(ssh->logctx, PKT_INCOMING, st->pktin->type,
1261 ssh2_pkt_type(ssh->pkt_ctx, st->pktin->type),
1262 st->pktin->data+6, st->pktin->length-6,
9a10ecf4 1263 nblanks, &blank);
1264 }
00db133f 1265
ff3187f6 1266 crFinish(st->pktin);
e5574168 1267}
1268
ff3187f6 1269static void ssh1_pktout_size(struct Packet *pkt, int len)
32874aea 1270{
374330e2 1271 int pad, biglen;
1272
1273 len += 5; /* type and CRC */
32874aea 1274 pad = 8 - (len % 8);
374330e2 1275 biglen = len + pad;
1276
ff3187f6 1277 pkt->length = len - 5;
1278 if (pkt->maxlen < biglen) {
1279 pkt->maxlen = biglen;
1280 pkt->data = sresize(pkt->data, biglen + 4 + APIEXTRA, unsigned char);
374330e2 1281 }
ff3187f6 1282 pkt->body = pkt->data + 4 + pad + 1;
4ba9b64b 1283}
374330e2 1284
ff3187f6 1285static struct Packet *s_wrpkt_start(int type, int len)
32874aea 1286{
ff3187f6 1287 struct Packet *pkt = ssh_new_packet();
1288 ssh1_pktout_size(pkt, len);
1289 pkt->type = type;
9a10ecf4 1290 /* Initialise log omission state */
ff3187f6 1291 pkt->nblanks = 0;
1292 pkt->blanks = NULL;
1293 return pkt;
374330e2 1294}
1295
ff3187f6 1296static int s_wrpkt_prepare(Ssh ssh, struct Packet *pkt)
32874aea 1297{
fd7a4aad 1298 int pad, biglen, i;
374330e2 1299 unsigned long crc;
fd7a4aad 1300#ifdef __SC__
1301 /*
1302 * XXX various versions of SC (including 8.8.4) screw up the
1303 * register allocation in this function and use the same register
1304 * (D6) for len and as a temporary, with predictable results. The
1305 * following sledgehammer prevents this.
1306 */
1307 volatile
1308#endif
1309 int len;
374330e2 1310
ff3187f6 1311 pkt->body[-1] = pkt->type;
4ba9b64b 1312
a8327734 1313 if (ssh->logctx)
ff3187f6 1314 log_packet(ssh->logctx, PKT_OUTGOING, pkt->type,
1315 ssh1_pkt_type(pkt->type),
1316 pkt->body, pkt->length,
1317 pkt->nblanks, pkt->blanks);
1318 sfree(pkt->blanks); pkt->blanks = NULL;
1319 pkt->nblanks = 0;
00db133f 1320
51470298 1321 if (ssh->v1_compressing) {
4ba9b64b 1322 unsigned char *compblk;
1323 int complen;
5366aed8 1324 zlib_compress_block(ssh->cs_comp_ctx,
ff3187f6 1325 pkt->body - 1, pkt->length + 1,
4ba9b64b 1326 &compblk, &complen);
ff3187f6 1327 ssh1_pktout_size(pkt, complen - 1);
1328 memcpy(pkt->body - 1, compblk, complen);
dcbde236 1329 sfree(compblk);
4ba9b64b 1330 }
1331
ff3187f6 1332 len = pkt->length + 5; /* type and CRC */
32874aea 1333 pad = 8 - (len % 8);
374330e2 1334 biglen = len + pad;
1335
32874aea 1336 for (i = 0; i < pad; i++)
ff3187f6 1337 pkt->data[i + 4] = random_byte();
1338 crc = crc32_compute(pkt->data + 4, biglen - 4);
1339 PUT_32BIT(pkt->data + biglen, crc);
1340 PUT_32BIT(pkt->data, len);
374330e2 1341
51470298 1342 if (ssh->cipher)
ff3187f6 1343 ssh->cipher->encrypt(ssh->v1_cipher_ctx, pkt->data + 4, biglen);
374330e2 1344
32874aea 1345 return biglen + 4;
39065bed 1346}
1347
ff3187f6 1348static void s_wrpkt(Ssh ssh, struct Packet *pkt)
32874aea 1349{
5471d09a 1350 int len, backlog;
ff3187f6 1351 len = s_wrpkt_prepare(ssh, pkt);
1352 backlog = sk_write(ssh->s, (char *)pkt->data, len);
5471d09a 1353 if (backlog > SSH_MAX_BACKLOG)
51470298 1354 ssh_throttle_all(ssh, 1, backlog);
39065bed 1355}
1356
ff3187f6 1357static void s_wrpkt_defer(Ssh ssh, struct Packet *pkt)
32874aea 1358{
39065bed 1359 int len;
ff3187f6 1360 len = s_wrpkt_prepare(ssh, pkt);
51470298 1361 if (ssh->deferred_len + len > ssh->deferred_size) {
1362 ssh->deferred_size = ssh->deferred_len + len + 128;
3d88e64d 1363 ssh->deferred_send_data = sresize(ssh->deferred_send_data,
1364 ssh->deferred_size,
1365 unsigned char);
39065bed 1366 }
ff3187f6 1367 memcpy(ssh->deferred_send_data + ssh->deferred_len, pkt->data, len);
51470298 1368 ssh->deferred_len += len;
374330e2 1369}
1370
fb09bf1c 1371/*
39065bed 1372 * Construct a packet with the specified contents.
fb09bf1c 1373 */
ff3187f6 1374static struct Packet *construct_packet(Ssh ssh, int pkttype,
1375 va_list ap1, va_list ap2)
fb09bf1c 1376{
fb09bf1c 1377 unsigned char *p, *argp, argchar;
1378 unsigned long argint;
1379 int pktlen, argtype, arglen;
7cca0d81 1380 Bignum bn;
ff3187f6 1381 struct Packet *pkt;
fb09bf1c 1382
1383 pktlen = 0;
39065bed 1384 while ((argtype = va_arg(ap1, int)) != PKT_END) {
fb09bf1c 1385 switch (argtype) {
1386 case PKT_INT:
39065bed 1387 (void) va_arg(ap1, int);
fb09bf1c 1388 pktlen += 4;
1389 break;
1390 case PKT_CHAR:
1ec39246 1391 (void) va_arg(ap1, int);
fb09bf1c 1392 pktlen++;
1393 break;
1394 case PKT_DATA:
39065bed 1395 (void) va_arg(ap1, unsigned char *);
1396 arglen = va_arg(ap1, int);
fb09bf1c 1397 pktlen += arglen;
1398 break;
1399 case PKT_STR:
39065bed 1400 argp = va_arg(ap1, unsigned char *);
d8baa528 1401 arglen = strlen((char *)argp);
fb09bf1c 1402 pktlen += 4 + arglen;
1403 break;
7cca0d81 1404 case PKT_BIGNUM:
39065bed 1405 bn = va_arg(ap1, Bignum);
32874aea 1406 pktlen += ssh1_bignum_length(bn);
7cca0d81 1407 break;
9a10ecf4 1408 case PKTT_PASSWORD:
1409 case PKTT_DATA:
1410 case PKTT_OTHER:
1411 /* ignore this pass */
1412 break;
fb09bf1c 1413 default:
1414 assert(0);
1415 }
1416 }
fb09bf1c 1417
ff3187f6 1418 pkt = s_wrpkt_start(pkttype, pktlen);
1419 p = pkt->body;
fb09bf1c 1420
39065bed 1421 while ((argtype = va_arg(ap2, int)) != PKT_END) {
ff3187f6 1422 int offset = p - pkt->body, len = 0;
fb09bf1c 1423 switch (argtype) {
9a10ecf4 1424 /* Actual fields in the packet */
fb09bf1c 1425 case PKT_INT:
39065bed 1426 argint = va_arg(ap2, int);
fb09bf1c 1427 PUT_32BIT(p, argint);
9a10ecf4 1428 len = 4;
fb09bf1c 1429 break;
1430 case PKT_CHAR:
1ec39246 1431 argchar = (unsigned char) va_arg(ap2, int);
fb09bf1c 1432 *p = argchar;
9a10ecf4 1433 len = 1;
fb09bf1c 1434 break;
1435 case PKT_DATA:
39065bed 1436 argp = va_arg(ap2, unsigned char *);
1437 arglen = va_arg(ap2, int);
fb09bf1c 1438 memcpy(p, argp, arglen);
9a10ecf4 1439 len = arglen;
fb09bf1c 1440 break;
1441 case PKT_STR:
39065bed 1442 argp = va_arg(ap2, unsigned char *);
d8baa528 1443 arglen = strlen((char *)argp);
fb09bf1c 1444 PUT_32BIT(p, arglen);
1445 memcpy(p + 4, argp, arglen);
9a10ecf4 1446 len = arglen + 4;
fb09bf1c 1447 break;
7cca0d81 1448 case PKT_BIGNUM:
39065bed 1449 bn = va_arg(ap2, Bignum);
9a10ecf4 1450 len = ssh1_write_bignum(p, bn);
1451 break;
1452 /* Tokens for modifications to packet logging */
1453 case PKTT_PASSWORD:
ff3187f6 1454 dont_log_password(ssh, pkt, PKTLOG_BLANK);
9a10ecf4 1455 break;
1456 case PKTT_DATA:
ff3187f6 1457 dont_log_data(ssh, pkt, PKTLOG_OMIT);
7cca0d81 1458 break;
9a10ecf4 1459 case PKTT_OTHER:
ff3187f6 1460 end_log_omission(ssh, pkt);
9a10ecf4 1461 break;
1462 }
1463 p += len;
1464 /* Deal with logfile omission, if required. */
ff3187f6 1465 if (len && (pkt->logmode != PKTLOG_EMIT)) {
1466 pkt->nblanks++;
1467 pkt->blanks = sresize(pkt->blanks, pkt->nblanks,
1468 struct logblank_t);
1469 pkt->blanks[pkt->nblanks-1].offset = offset;
1470 pkt->blanks[pkt->nblanks-1].len = len;
1471 pkt->blanks[pkt->nblanks-1].type = pkt->logmode;
fb09bf1c 1472 }
1473 }
ff3187f6 1474
1475 return pkt;
39065bed 1476}
fb09bf1c 1477
51470298 1478static void send_packet(Ssh ssh, int pkttype, ...)
32874aea 1479{
ff3187f6 1480 struct Packet *pkt;
39065bed 1481 va_list ap1, ap2;
1482 va_start(ap1, pkttype);
1483 va_start(ap2, pkttype);
ff3187f6 1484 pkt = construct_packet(ssh, pkttype, ap1, ap2);
1485 va_end(ap2);
1486 va_end(ap1);
1487 s_wrpkt(ssh, pkt);
1488 ssh_free_packet(pkt);
fb09bf1c 1489}
1490
51470298 1491static void defer_packet(Ssh ssh, int pkttype, ...)
32874aea 1492{
ff3187f6 1493 struct Packet *pkt;
39065bed 1494 va_list ap1, ap2;
1495 va_start(ap1, pkttype);
1496 va_start(ap2, pkttype);
ff3187f6 1497 pkt = construct_packet(ssh, pkttype, ap1, ap2);
1498 va_end(ap2);
1499 va_end(ap1);
1500 s_wrpkt_defer(ssh, pkt);
1501 ssh_free_packet(pkt);
39065bed 1502}
1503
32874aea 1504static int ssh_versioncmp(char *a, char *b)
1505{
9697bfd2 1506 char *ae, *be;
1507 unsigned long av, bv;
1508
43aa02a7 1509 av = strtoul(a, &ae, 10);
1510 bv = strtoul(b, &be, 10);
32874aea 1511 if (av != bv)
1512 return (av < bv ? -1 : +1);
1513 if (*ae == '.')
1514 ae++;
1515 if (*be == '.')
1516 be++;
43aa02a7 1517 av = strtoul(ae, &ae, 10);
1518 bv = strtoul(be, &be, 10);
32874aea 1519 if (av != bv)
1520 return (av < bv ? -1 : +1);
9697bfd2 1521 return 0;
1522}
1523
e5574168 1524/*
a92dd380 1525 * Utility routines for putting an SSH-protocol `string' and
1526 * `uint32' into a SHA state.
e5574168 1527 */
1528#include <stdio.h>
32874aea 1529static void sha_string(SHA_State * s, void *str, int len)
1530{
e5574168 1531 unsigned char lenblk[4];
e5574168 1532 PUT_32BIT(lenblk, len);
e5574168 1533 SHA_Bytes(s, lenblk, 4);
e5574168 1534 SHA_Bytes(s, str, len);
1535}
1536
32874aea 1537static void sha_uint32(SHA_State * s, unsigned i)
1538{
a92dd380 1539 unsigned char intblk[4];
1540 PUT_32BIT(intblk, i);
1541 SHA_Bytes(s, intblk, 4);
1542}
1543
7cca0d81 1544/*
1545 * SSH2 packet construction functions.
1546 */
ff3187f6 1547static void ssh2_pkt_ensure(struct Packet *pkt, int length)
32874aea 1548{
ff3187f6 1549 if (pkt->maxlen < length) {
1550 pkt->maxlen = length + 256;
1551 pkt->data = sresize(pkt->data, pkt->maxlen + APIEXTRA, unsigned char);
7cca0d81 1552 }
783415f8 1553}
ff3187f6 1554static void ssh2_pkt_adddata(struct Packet *pkt, void *data, int len)
32874aea 1555{
ff3187f6 1556 if (pkt->logmode != PKTLOG_EMIT) {
1557 pkt->nblanks++;
1558 pkt->blanks = sresize(pkt->blanks, pkt->nblanks, struct logblank_t);
1559 pkt->blanks[pkt->nblanks-1].offset = pkt->length - 6;
1560 pkt->blanks[pkt->nblanks-1].len = len;
1561 pkt->blanks[pkt->nblanks-1].type = pkt->logmode;
1562 }
1563 pkt->length += len;
1564 ssh2_pkt_ensure(pkt, pkt->length);
1565 memcpy(pkt->data + pkt->length - len, data, len);
7cca0d81 1566}
ff3187f6 1567static void ssh2_pkt_addbyte(struct Packet *pkt, unsigned char byte)
32874aea 1568{
ff3187f6 1569 ssh2_pkt_adddata(pkt, &byte, 1);
7cca0d81 1570}
ff3187f6 1571static struct Packet *ssh2_pkt_init(int pkt_type)
32874aea 1572{
ff3187f6 1573 struct Packet *pkt = ssh_new_packet();
1574 pkt->length = 5;
1575 ssh2_pkt_addbyte(pkt, (unsigned char) pkt_type);
1576 return pkt;
7cca0d81 1577}
ff3187f6 1578static void ssh2_pkt_addbool(struct Packet *pkt, unsigned char value)
32874aea 1579{
ff3187f6 1580 ssh2_pkt_adddata(pkt, &value, 1);
7cca0d81 1581}
ff3187f6 1582static void ssh2_pkt_adduint32(struct Packet *pkt, unsigned long value)
32874aea 1583{
7cca0d81 1584 unsigned char x[4];
1585 PUT_32BIT(x, value);
ff3187f6 1586 ssh2_pkt_adddata(pkt, x, 4);
7cca0d81 1587}
ff3187f6 1588static void ssh2_pkt_addstring_start(struct Packet *pkt)
32874aea 1589{
ff3187f6 1590 ssh2_pkt_adduint32(pkt, 0);
1591 pkt->savedpos = pkt->length;
7cca0d81 1592}
ff3187f6 1593static void ssh2_pkt_addstring_str(struct Packet *pkt, char *data)
32874aea 1594{
ff3187f6 1595 ssh2_pkt_adddata(pkt, data, strlen(data));
1596 PUT_32BIT(pkt->data + pkt->savedpos - 4, pkt->length - pkt->savedpos);
7cca0d81 1597}
ff3187f6 1598static void ssh2_pkt_addstring_data(struct Packet *pkt, char *data, int len)
32874aea 1599{
ff3187f6 1600 ssh2_pkt_adddata(pkt, data, len);
1601 PUT_32BIT(pkt->data + pkt->savedpos - 4, pkt->length - pkt->savedpos);
7cca0d81 1602}
ff3187f6 1603static void ssh2_pkt_addstring(struct Packet *pkt, char *data)
32874aea 1604{
ff3187f6 1605 ssh2_pkt_addstring_start(pkt);
1606 ssh2_pkt_addstring_str(pkt, data);
7cca0d81 1607}
d8baa528 1608static unsigned char *ssh2_mpint_fmt(Bignum b, int *len)
32874aea 1609{
7cca0d81 1610 unsigned char *p;
32874aea 1611 int i, n = (bignum_bitcount(b) + 7) / 8;
3d88e64d 1612 p = snewn(n + 1, unsigned char);
7cca0d81 1613 if (!p)
32874aea 1614 fatalbox("out of memory");
7cca0d81 1615 p[0] = 0;
3709bfe9 1616 for (i = 1; i <= n; i++)
32874aea 1617 p[i] = bignum_byte(b, n - i);
7cca0d81 1618 i = 0;
32874aea 1619 while (i <= n && p[i] == 0 && (p[i + 1] & 0x80) == 0)
1620 i++;
1621 memmove(p, p + i, n + 1 - i);
1622 *len = n + 1 - i;
7cca0d81 1623 return p;
1624}
ff3187f6 1625static void ssh2_pkt_addmp(struct Packet *pkt, Bignum b)
32874aea 1626{
7cca0d81 1627 unsigned char *p;
1628 int len;
1629 p = ssh2_mpint_fmt(b, &len);
ff3187f6 1630 ssh2_pkt_addstring_start(pkt);
1631 ssh2_pkt_addstring_data(pkt, (char *)p, len);
dcbde236 1632 sfree(p);
7cca0d81 1633}
b185170a 1634
1635/*
1636 * Construct an SSH2 final-form packet: compress it, encrypt it,
1637 * put the MAC on it. Final packet, ready to be sent, is stored in
ff3187f6 1638 * pkt->data. Total length is returned.
b185170a 1639 */
ff3187f6 1640static int ssh2_pkt_construct(Ssh ssh, struct Packet *pkt)
32874aea 1641{
7cca0d81 1642 int cipherblk, maclen, padding, i;
7cca0d81 1643
a8327734 1644 if (ssh->logctx)
ff3187f6 1645 log_packet(ssh->logctx, PKT_OUTGOING, pkt->data[5],
1646 ssh2_pkt_type(ssh->pkt_ctx, pkt->data[5]),
1647 pkt->data + 6, pkt->length - 6,
1648 pkt->nblanks, pkt->blanks);
1649 sfree(pkt->blanks); pkt->blanks = NULL;
1650 pkt->nblanks = 0;
00db133f 1651
7cca0d81 1652 /*
4ba9b64b 1653 * Compress packet payload.
1654 */
4ba9b64b 1655 {
1656 unsigned char *newpayload;
1657 int newlen;
51470298 1658 if (ssh->cscomp &&
ff3187f6 1659 ssh->cscomp->compress(ssh->cs_comp_ctx, pkt->data + 5,
1660 pkt->length - 5,
51470298 1661 &newpayload, &newlen)) {
ff3187f6 1662 pkt->length = 5;
1663 ssh2_pkt_adddata(pkt, newpayload, newlen);
dcbde236 1664 sfree(newpayload);
4ba9b64b 1665 }
1666 }
1667
1668 /*
7cca0d81 1669 * Add padding. At least four bytes, and must also bring total
1670 * length (minus MAC) up to a multiple of the block size.
1671 */
51470298 1672 cipherblk = ssh->cscipher ? ssh->cscipher->blksize : 8; /* block size */
32874aea 1673 cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
7cca0d81 1674 padding = 4;
32874aea 1675 padding +=
ff3187f6 1676 (cipherblk - (pkt->length + padding) % cipherblk) % cipherblk;
51470298 1677 maclen = ssh->csmac ? ssh->csmac->len : 0;
ff3187f6 1678 ssh2_pkt_ensure(pkt, pkt->length + padding + maclen);
1679 pkt->data[4] = padding;
7cca0d81 1680 for (i = 0; i < padding; i++)
ff3187f6 1681 pkt->data[pkt->length + i] = random_byte();
1682 PUT_32BIT(pkt->data, pkt->length + padding - 4);
51470298 1683 if (ssh->csmac)
ff3187f6 1684 ssh->csmac->generate(ssh->cs_mac_ctx, pkt->data,
1685 pkt->length + padding,
51470298 1686 ssh->v2_outgoing_sequence);
1687 ssh->v2_outgoing_sequence++; /* whether or not we MACed */
1688
1689 if (ssh->cscipher)
371e569c 1690 ssh->cscipher->encrypt(ssh->cs_cipher_ctx,
ff3187f6 1691 pkt->data, pkt->length + padding);
51470298 1692
9442dd57 1693 pkt->encrypted_len = pkt->length + padding;
1694
ff3187f6 1695 /* Ready-to-send packet starts at pkt->data. We return length. */
1696 return pkt->length + padding + maclen;
b185170a 1697}
1698
1699/*
590f6a5f 1700 * Routines called from the main SSH code to send packets. There
1701 * are quite a few of these, because we have two separate
1702 * mechanisms for delaying the sending of packets:
1703 *
1704 * - In order to send an IGNORE message and a password message in
1705 * a single fixed-length blob, we require the ability to
1706 * concatenate the encrypted forms of those two packets _into_ a
1707 * single blob and then pass it to our <network.h> transport
1708 * layer in one go. Hence, there's a deferment mechanism which
1709 * works after packet encryption.
1710 *
1711 * - In order to avoid sending any connection-layer messages
1712 * during repeat key exchange, we have to queue up any such
1713 * outgoing messages _before_ they are encrypted (and in
1714 * particular before they're allocated sequence numbers), and
1715 * then send them once we've finished.
1716 *
1717 * I call these mechanisms `defer' and `queue' respectively, so as
1718 * to distinguish them reasonably easily.
1719 *
1720 * The functions send_noqueue() and defer_noqueue() free the packet
1721 * structure they are passed. Every outgoing packet goes through
1722 * precisely one of these functions in its life; packets passed to
1723 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1724 * these or get queued, and then when the queue is later emptied
1725 * the packets are all passed to defer_noqueue().
b185170a 1726 */
590f6a5f 1727
1728/*
1729 * Send an SSH2 packet immediately, without queuing or deferring.
1730 */
1731static void ssh2_pkt_send_noqueue(Ssh ssh, struct Packet *pkt)
32874aea 1732{
5471d09a 1733 int len;
1734 int backlog;
ff3187f6 1735 len = ssh2_pkt_construct(ssh, pkt);
1736 backlog = sk_write(ssh->s, (char *)pkt->data, len);
5471d09a 1737 if (backlog > SSH_MAX_BACKLOG)
51470298 1738 ssh_throttle_all(ssh, 1, backlog);
9442dd57 1739
1740 ssh->outgoing_data_size += pkt->encrypted_len;
1741 if (!ssh->kex_in_progress &&
d57f70af 1742 ssh->max_data_size != 0 &&
1743 ssh->outgoing_data_size > ssh->max_data_size)
f382c87d 1744 do_ssh2_transport(ssh, "too much data sent", -1, NULL);
9442dd57 1745
ff3187f6 1746 ssh_free_packet(pkt);
b185170a 1747}
1748
1749/*
590f6a5f 1750 * Defer an SSH2 packet.
b185170a 1751 */
590f6a5f 1752static void ssh2_pkt_defer_noqueue(Ssh ssh, struct Packet *pkt)
32874aea 1753{
ff3187f6 1754 int len = ssh2_pkt_construct(ssh, pkt);
51470298 1755 if (ssh->deferred_len + len > ssh->deferred_size) {
1756 ssh->deferred_size = ssh->deferred_len + len + 128;
3d88e64d 1757 ssh->deferred_send_data = sresize(ssh->deferred_send_data,
1758 ssh->deferred_size,
1759 unsigned char);
b185170a 1760 }
ff3187f6 1761 memcpy(ssh->deferred_send_data + ssh->deferred_len, pkt->data, len);
51470298 1762 ssh->deferred_len += len;
9442dd57 1763 ssh->deferred_data_size += pkt->encrypted_len;
ff3187f6 1764 ssh_free_packet(pkt);
b185170a 1765}
1766
1767/*
590f6a5f 1768 * Queue an SSH2 packet.
1769 */
1770static void ssh2_pkt_queue(Ssh ssh, struct Packet *pkt)
1771{
1772 assert(ssh->queueing);
1773
1774 if (ssh->queuelen >= ssh->queuesize) {
1775 ssh->queuesize = ssh->queuelen + 32;
1776 ssh->queue = sresize(ssh->queue, ssh->queuesize, struct Packet *);
1777 }
1778
1779 ssh->queue[ssh->queuelen++] = pkt;
1780}
1781
1782/*
1783 * Either queue or send a packet, depending on whether queueing is
1784 * set.
1785 */
1786static void ssh2_pkt_send(Ssh ssh, struct Packet *pkt)
1787{
1788 if (ssh->queueing)
1789 ssh2_pkt_queue(ssh, pkt);
1790 else
1791 ssh2_pkt_send_noqueue(ssh, pkt);
1792}
1793
1794/*
1795 * Either queue or defer a packet, depending on whether queueing is
1796 * set.
1797 */
1798static void ssh2_pkt_defer(Ssh ssh, struct Packet *pkt)
1799{
1800 if (ssh->queueing)
1801 ssh2_pkt_queue(ssh, pkt);
1802 else
1803 ssh2_pkt_defer_noqueue(ssh, pkt);
1804}
1805
1806/*
b185170a 1807 * Send the whole deferred data block constructed by
39065bed 1808 * ssh2_pkt_defer() or SSH1's defer_packet().
590f6a5f 1809 *
1810 * The expected use of the defer mechanism is that you call
1811 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1812 * not currently queueing, this simply sets up deferred_send_data
1813 * and then sends it. If we _are_ currently queueing, the calls to
1814 * ssh2_pkt_defer() put the deferred packets on to the queue
1815 * instead, and therefore ssh_pkt_defersend() has no deferred data
1816 * to send. Hence, there's no need to make it conditional on
1817 * ssh->queueing.
b185170a 1818 */
51470298 1819static void ssh_pkt_defersend(Ssh ssh)
32874aea 1820{
5471d09a 1821 int backlog;
d8baa528 1822 backlog = sk_write(ssh->s, (char *)ssh->deferred_send_data,
1823 ssh->deferred_len);
51470298 1824 ssh->deferred_len = ssh->deferred_size = 0;
1825 sfree(ssh->deferred_send_data);
1826 ssh->deferred_send_data = NULL;
5471d09a 1827 if (backlog > SSH_MAX_BACKLOG)
51470298 1828 ssh_throttle_all(ssh, 1, backlog);
9442dd57 1829
1830 ssh->outgoing_data_size += ssh->deferred_data_size;
1831 if (!ssh->kex_in_progress &&
d57f70af 1832 ssh->max_data_size != 0 &&
1833 ssh->outgoing_data_size > ssh->max_data_size)
f382c87d 1834 do_ssh2_transport(ssh, "too much data sent", -1, NULL);
9442dd57 1835 ssh->deferred_data_size = 0;
7cca0d81 1836}
1837
590f6a5f 1838/*
1839 * Send all queued SSH2 packets. We send them by means of
1840 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1841 * packets that needed to be lumped together.
1842 */
1843static void ssh2_pkt_queuesend(Ssh ssh)
1844{
1845 int i;
1846
1847 assert(!ssh->queueing);
1848
1849 for (i = 0; i < ssh->queuelen; i++)
1850 ssh2_pkt_defer_noqueue(ssh, ssh->queue[i]);
1851 ssh->queuelen = 0;
1852
1853 ssh_pkt_defersend(ssh);
1854}
1855
7cca0d81 1856#if 0
32874aea 1857void bndebug(char *string, Bignum b)
1858{
7cca0d81 1859 unsigned char *p;
1860 int i, len;
1861 p = ssh2_mpint_fmt(b, &len);
1862 debug(("%s", string));
1863 for (i = 0; i < len; i++)
32874aea 1864 debug((" %02x", p[i]));
765c4200 1865 debug(("\n"));
dcbde236 1866 sfree(p);
7cca0d81 1867}
1868#endif
1869
32874aea 1870static void sha_mpint(SHA_State * s, Bignum b)
1871{
7cca0d81 1872 unsigned char *p;
1873 int len;
1874 p = ssh2_mpint_fmt(b, &len);
1875 sha_string(s, p, len);
dcbde236 1876 sfree(p);
7cca0d81 1877}
1878
1879/*
0016d70b 1880 * Packet decode functions for both SSH1 and SSH2.
7cca0d81 1881 */
ff3187f6 1882static unsigned long ssh_pkt_getuint32(struct Packet *pkt)
32874aea 1883{
7cca0d81 1884 unsigned long value;
ff3187f6 1885 if (pkt->length - pkt->savedpos < 4)
32874aea 1886 return 0; /* arrgh, no way to decline (FIXME?) */
ff3187f6 1887 value = GET_32BIT(pkt->body + pkt->savedpos);
1888 pkt->savedpos += 4;
7cca0d81 1889 return value;
1890}
ff3187f6 1891static int ssh2_pkt_getbool(struct Packet *pkt)
32874aea 1892{
65a22376 1893 unsigned long value;
ff3187f6 1894 if (pkt->length - pkt->savedpos < 1)
32874aea 1895 return 0; /* arrgh, no way to decline (FIXME?) */
ff3187f6 1896 value = pkt->body[pkt->savedpos] != 0;
1897 pkt->savedpos++;
65a22376 1898 return value;
1899}
ff3187f6 1900static void ssh_pkt_getstring(struct Packet *pkt, char **p, int *length)
32874aea 1901{
57356d63 1902 int len;
7cca0d81 1903 *p = NULL;
45068b27 1904 *length = 0;
ff3187f6 1905 if (pkt->length - pkt->savedpos < 4)
32874aea 1906 return;
ff3187f6 1907 len = GET_32BIT(pkt->body + pkt->savedpos);
57356d63 1908 if (len < 0)
1909 return;
1910 *length = len;
ff3187f6 1911 pkt->savedpos += 4;
1912 if (pkt->length - pkt->savedpos < *length)
32874aea 1913 return;
ff3187f6 1914 *p = (char *)(pkt->body + pkt->savedpos);
1915 pkt->savedpos += *length;
7cca0d81 1916}
ff3187f6 1917static void *ssh_pkt_getdata(struct Packet *pkt, int length)
0016d70b 1918{
ff3187f6 1919 if (pkt->length - pkt->savedpos < length)
0016d70b 1920 return NULL;
ff3187f6 1921 pkt->savedpos += length;
1922 return pkt->body + (pkt->savedpos - length);
0016d70b 1923}
ff3187f6 1924static int ssh1_pkt_getrsakey(struct Packet *pkt, struct RSAKey *key,
0016d70b 1925 unsigned char **keystr)
1926{
1927 int j;
1928
ff3187f6 1929 j = makekey(pkt->body + pkt->savedpos,
1930 pkt->length - pkt->savedpos,
0016d70b 1931 key, keystr, 0);
1932
1933 if (j < 0)
1934 return FALSE;
1935
ff3187f6 1936 pkt->savedpos += j;
1937 assert(pkt->savedpos < pkt->length);
0016d70b 1938
1939 return TRUE;
1940}
ff3187f6 1941static Bignum ssh1_pkt_getmp(struct Packet *pkt)
0016d70b 1942{
1943 int j;
1944 Bignum b;
1945
ff3187f6 1946 j = ssh1_read_bignum(pkt->body + pkt->savedpos,
1947 pkt->length - pkt->savedpos, &b);
0016d70b 1948
1949 if (j < 0)
1950 return NULL;
1951
ff3187f6 1952 pkt->savedpos += j;
0016d70b 1953 return b;
1954}
ff3187f6 1955static Bignum ssh2_pkt_getmp(struct Packet *pkt)
32874aea 1956{
7cca0d81 1957 char *p;
3709bfe9 1958 int length;
7cca0d81 1959 Bignum b;
1960
ff3187f6 1961 ssh_pkt_getstring(pkt, &p, &length);
7cca0d81 1962 if (!p)
32874aea 1963 return NULL;
ff3187f6 1964 if (p[0] & 0x80)
32874aea 1965 return NULL;
d8baa528 1966 b = bignum_from_bytes((unsigned char *)p, length);
7cca0d81 1967 return b;
1968}
1969
7d503c31 1970/*
1dd353b5 1971 * Helper function to add an SSH2 signature blob to a packet.
1972 * Expects to be shown the public key blob as well as the signature
1973 * blob. Normally works just like ssh2_pkt_addstring, but will
1974 * fiddle with the signature packet if necessary for
1975 * BUG_SSH2_RSA_PADDING.
1976 */
ff3187f6 1977static void ssh2_add_sigblob(Ssh ssh, struct Packet *pkt,
1978 void *pkblob_v, int pkblob_len,
1dd353b5 1979 void *sigblob_v, int sigblob_len)
1980{
1981 unsigned char *pkblob = (unsigned char *)pkblob_v;
1982 unsigned char *sigblob = (unsigned char *)sigblob_v;
1983
1984 /* dmemdump(pkblob, pkblob_len); */
1985 /* dmemdump(sigblob, sigblob_len); */
1986
1987 /*
1988 * See if this is in fact an ssh-rsa signature and a buggy
1989 * server; otherwise we can just do this the easy way.
1990 */
51470298 1991 if ((ssh->remote_bugs & BUG_SSH2_RSA_PADDING) &&
1dd353b5 1992 (GET_32BIT(pkblob) == 7 && !memcmp(pkblob+4, "ssh-rsa", 7))) {
1993 int pos, len, siglen;
1994
1995 /*
1996 * Find the byte length of the modulus.
1997 */
1998
1999 pos = 4+7; /* skip over "ssh-rsa" */
2000 pos += 4 + GET_32BIT(pkblob+pos); /* skip over exponent */
2001 len = GET_32BIT(pkblob+pos); /* find length of modulus */
2002 pos += 4; /* find modulus itself */
2003 while (len > 0 && pkblob[pos] == 0)
2004 len--, pos++;
2005 /* debug(("modulus length is %d\n", len)); */
2006
2007 /*
2008 * Now find the signature integer.
2009 */
2010 pos = 4+7; /* skip over "ssh-rsa" */
2011 siglen = GET_32BIT(sigblob+pos);
2012 /* debug(("signature length is %d\n", siglen)); */
2013
2014 if (len != siglen) {
2015 unsigned char newlen[4];
ff3187f6 2016 ssh2_pkt_addstring_start(pkt);
2017 ssh2_pkt_addstring_data(pkt, (char *)sigblob, pos);
1dd353b5 2018 /* dmemdump(sigblob, pos); */
2019 pos += 4; /* point to start of actual sig */
2020 PUT_32BIT(newlen, len);
ff3187f6 2021 ssh2_pkt_addstring_data(pkt, (char *)newlen, 4);
1dd353b5 2022 /* dmemdump(newlen, 4); */
2023 newlen[0] = 0;
2024 while (len-- > siglen) {
ff3187f6 2025 ssh2_pkt_addstring_data(pkt, (char *)newlen, 1);
1dd353b5 2026 /* dmemdump(newlen, 1); */
2027 }
ff3187f6 2028 ssh2_pkt_addstring_data(pkt, (char *)(sigblob+pos), siglen);
1dd353b5 2029 /* dmemdump(sigblob+pos, siglen); */
2030 return;
2031 }
2032
2033 /* Otherwise fall through and do it the easy way. */
2034 }
2035
ff3187f6 2036 ssh2_pkt_addstring_start(pkt);
2037 ssh2_pkt_addstring_data(pkt, (char *)sigblob, sigblob_len);
1dd353b5 2038}
2039
2040/*
7d503c31 2041 * Examine the remote side's version string and compare it against
2042 * a list of known buggy implementations.
2043 */
51470298 2044static void ssh_detect_bugs(Ssh ssh, char *vstring)
32874aea 2045{
2046 char *imp; /* pointer to implementation part */
7d503c31 2047 imp = vstring;
2048 imp += strcspn(imp, "-");
bd358db1 2049 if (*imp) imp++;
7d503c31 2050 imp += strcspn(imp, "-");
bd358db1 2051 if (*imp) imp++;
7d503c31 2052
51470298 2053 ssh->remote_bugs = 0;
7d503c31 2054
5ecd7ad0 2055 if (ssh->cfg.sshbug_ignore1 == FORCE_ON ||
2056 (ssh->cfg.sshbug_ignore1 == AUTO &&
2c9c6388 2057 (!strcmp(imp, "1.2.18") || !strcmp(imp, "1.2.19") ||
2058 !strcmp(imp, "1.2.20") || !strcmp(imp, "1.2.21") ||
46ac09aa 2059 !strcmp(imp, "1.2.22") || !strcmp(imp, "Cisco-1.25") ||
bd0b4caf 2060 !strcmp(imp, "OSU_1.4alpha3") || !strcmp(imp, "OSU_1.5alpha4")))) {
32874aea 2061 /*
2062 * These versions don't support SSH1_MSG_IGNORE, so we have
2063 * to use a different defence against password length
2064 * sniffing.
2065 */
51470298 2066 ssh->remote_bugs |= BUG_CHOKES_ON_SSH1_IGNORE;
32874aea 2067 logevent("We believe remote version has SSH1 ignore bug");
7d503c31 2068 }
2069
5ecd7ad0 2070 if (ssh->cfg.sshbug_plainpw1 == FORCE_ON ||
2071 (ssh->cfg.sshbug_plainpw1 == AUTO &&
46ac09aa 2072 (!strcmp(imp, "Cisco-1.25") || !strcmp(imp, "OSU_1.4alpha3")))) {
bd358db1 2073 /*
2074 * These versions need a plain password sent; they can't
2075 * handle having a null and a random length of data after
2076 * the password.
2077 */
51470298 2078 ssh->remote_bugs |= BUG_NEEDS_SSH1_PLAIN_PASSWORD;
bd358db1 2079 logevent("We believe remote version needs a plain SSH1 password");
2080 }
2081
5ecd7ad0 2082 if (ssh->cfg.sshbug_rsa1 == FORCE_ON ||
2083 (ssh->cfg.sshbug_rsa1 == AUTO &&
2c9c6388 2084 (!strcmp(imp, "Cisco-1.25")))) {
0df73905 2085 /*
2086 * These versions apparently have no clue whatever about
2087 * RSA authentication and will panic and die if they see
2088 * an AUTH_RSA message.
2089 */
51470298 2090 ssh->remote_bugs |= BUG_CHOKES_ON_RSA;
0df73905 2091 logevent("We believe remote version can't handle RSA authentication");
2092 }
2093
5ecd7ad0 2094 if (ssh->cfg.sshbug_hmac2 == FORCE_ON ||
2095 (ssh->cfg.sshbug_hmac2 == AUTO &&
b9f387af 2096 !wc_match("* VShell", imp) &&
831301f6 2097 (wc_match("2.1.0*", imp) || wc_match("2.0.*", imp) ||
2098 wc_match("2.2.0*", imp) || wc_match("2.3.0*", imp) ||
2099 wc_match("2.1 *", imp)))) {
32874aea 2100 /*
2101 * These versions have the HMAC bug.
2102 */
51470298 2103 ssh->remote_bugs |= BUG_SSH2_HMAC;
32874aea 2104 logevent("We believe remote version has SSH2 HMAC bug");
7d503c31 2105 }
1dd353b5 2106
5ecd7ad0 2107 if (ssh->cfg.sshbug_derivekey2 == FORCE_ON ||
2108 (ssh->cfg.sshbug_derivekey2 == AUTO &&
b9f387af 2109 !wc_match("* VShell", imp) &&
2856a1b9 2110 (wc_match("2.0.0*", imp) || wc_match("2.0.10*", imp) ))) {
088bde77 2111 /*
2112 * These versions have the key-derivation bug (failing to
2113 * include the literal shared secret in the hashes that
2114 * generate the keys).
2115 */
51470298 2116 ssh->remote_bugs |= BUG_SSH2_DERIVEKEY;
088bde77 2117 logevent("We believe remote version has SSH2 key-derivation bug");
2118 }
2119
5ecd7ad0 2120 if (ssh->cfg.sshbug_rsapad2 == FORCE_ON ||
2121 (ssh->cfg.sshbug_rsapad2 == AUTO &&
831301f6 2122 (wc_match("OpenSSH_2.[5-9]*", imp) ||
2123 wc_match("OpenSSH_3.[0-2]*", imp)))) {
1dd353b5 2124 /*
2125 * These versions have the SSH2 RSA padding bug.
2126 */
51470298 2127 ssh->remote_bugs |= BUG_SSH2_RSA_PADDING;
1dd353b5 2128 logevent("We believe remote version has SSH2 RSA padding bug");
2129 }
8e975795 2130
dda87a28 2131 if (ssh->cfg.sshbug_pksessid2 == FORCE_ON ||
2132 (ssh->cfg.sshbug_pksessid2 == AUTO &&
2133 wc_match("OpenSSH_2.[0-2]*", imp))) {
2134 /*
2135 * These versions have the SSH2 session-ID bug in
2136 * public-key authentication.
2137 */
2138 ssh->remote_bugs |= BUG_SSH2_PK_SESSIONID;
2139 logevent("We believe remote version has SSH2 public-key-session-ID bug");
2140 }
f382c87d 2141
2142 if (ssh->cfg.sshbug_rekey2 == FORCE_ON ||
2143 (ssh->cfg.sshbug_rekey2 == AUTO &&
e12d95a5 2144 (wc_match("OpenSSH_2.[0-4]*", imp) ||
2145 wc_match("OpenSSH_2.5.[0-3]*", imp) ||
2146 wc_match("Sun_SSH_1.0", imp) ||
7cb41bb2 2147 wc_match("Sun_SSH_1.0.1", imp)))) {
f382c87d 2148 /*
e12d95a5 2149 * These versions have the SSH2 rekey bug.
f382c87d 2150 */
2151 ssh->remote_bugs |= BUG_SSH2_REKEY;
e12d95a5 2152 logevent("We believe remote version has SSH2 rekey bug");
f382c87d 2153 }
7d503c31 2154}
2155
d38d6a1f 2156/*
2157 * The `software version' part of an SSH version string is required
2158 * to contain no spaces or minus signs.
2159 */
2160static void ssh_fix_verstring(char *str)
2161{
2162 /* Eat "SSH-<protoversion>-". */
2163 assert(*str == 'S'); str++;
2164 assert(*str == 'S'); str++;
2165 assert(*str == 'H'); str++;
2166 assert(*str == '-'); str++;
2167 while (*str && *str != '-') str++;
2168 assert(*str == '-'); str++;
2169
2170 /* Convert minus signs and spaces in the remaining string into
2171 * underscores. */
2172 while (*str) {
2173 if (*str == '-' || *str == ' ')
2174 *str = '_';
2175 str++;
2176 }
2177}
2178
51470298 2179static int do_ssh_init(Ssh ssh, unsigned char c)
32874aea 2180{
51470298 2181 struct do_ssh_init_state {
2182 int vslen;
2183 char version[10];
2184 char *vstring;
2185 int vstrsize;
2186 int i;
2187 int proto1, proto2;
2188 };
2189 crState(do_ssh_init_state);
374330e2 2190
51470298 2191 crBegin(ssh->do_ssh_init_crstate);
8df7a775 2192
2193 /* Search for the string "SSH-" in the input. */
51470298 2194 s->i = 0;
8df7a775 2195 while (1) {
2196 static const int transS[] = { 1, 2, 2, 1 };
2197 static const int transH[] = { 0, 0, 3, 0 };
2198 static const int transminus[] = { 0, 0, 0, -1 };
32874aea 2199 if (c == 'S')
51470298 2200 s->i = transS[s->i];
32874aea 2201 else if (c == 'H')
51470298 2202 s->i = transH[s->i];
32874aea 2203 else if (c == '-')
51470298 2204 s->i = transminus[s->i];
32874aea 2205 else
51470298 2206 s->i = 0;
2207 if (s->i < 0)
8df7a775 2208 break;
2209 crReturn(1); /* get another character */
374330e2 2210 }
8df7a775 2211
51470298 2212 s->vstrsize = 16;
3d88e64d 2213 s->vstring = snewn(s->vstrsize, char);
51470298 2214 strcpy(s->vstring, "SSH-");
2215 s->vslen = 4;
2216 s->i = 0;
374330e2 2217 while (1) {
8df7a775 2218 crReturn(1); /* get another char */
51470298 2219 if (s->vslen >= s->vstrsize - 1) {
2220 s->vstrsize += 16;
3d88e64d 2221 s->vstring = sresize(s->vstring, s->vstrsize, char);
32874aea 2222 }
51470298 2223 s->vstring[s->vslen++] = c;
2224 if (s->i >= 0) {
374330e2 2225 if (c == '-') {
51470298 2226 s->version[s->i] = '\0';
2227 s->i = -1;
2228 } else if (s->i < sizeof(s->version) - 1)
2229 s->version[s->i++] = c;
c4ffc4d0 2230 } else if (c == '\012')
374330e2 2231 break;
2232 }
2233
51470298 2234 ssh->agentfwd_enabled = FALSE;
2235 ssh->rdpkt2_state.incoming_sequence = 0;
960e736a 2236
51470298 2237 s->vstring[s->vslen] = 0;
a7d4653a 2238 s->vstring[strcspn(s->vstring, "\015\012")] = '\0';/* remove EOL chars */
51470298 2239 {
2240 char *vlog;
3d88e64d 2241 vlog = snewn(20 + s->vslen, char);
51470298 2242 sprintf(vlog, "Server version: %s", s->vstring);
2243 logevent(vlog);
2244 sfree(vlog);
2245 }
2246 ssh_detect_bugs(ssh, s->vstring);
c5e9c988 2247
adf799dd 2248 /*
38d228a2 2249 * Decide which SSH protocol version to support.
adf799dd 2250 */
38d228a2 2251
2252 /* Anything strictly below "2.0" means protocol 1 is supported. */
51470298 2253 s->proto1 = ssh_versioncmp(s->version, "2.0") < 0;
38d228a2 2254 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
51470298 2255 s->proto2 = ssh_versioncmp(s->version, "1.99") >= 0;
38d228a2 2256
86916870 2257 if (ssh->cfg.sshprot == 0 && !s->proto1) {
6b5cf8b4 2258 bombout(("SSH protocol version 1 required by user but not provided by server"));
7ffdbc1a 2259 crStop(0);
38d228a2 2260 }
86916870 2261 if (ssh->cfg.sshprot == 3 && !s->proto2) {
6b5cf8b4 2262 bombout(("SSH protocol version 2 required by user but not provided by server"));
7ffdbc1a 2263 crStop(0);
38d228a2 2264 }
2265
d38d6a1f 2266 {
2267 char *verstring;
2268
2269 if (s->proto2 && (ssh->cfg.sshprot >= 2 || !s->proto1)) {
2270 /*
2271 * Construct a v2 version string.
2272 */
a7d4653a 2273 verstring = dupprintf("SSH-2.0-%s\015\012", sshver);
d38d6a1f 2274 ssh->version = 2;
2275 } else {
2276 /*
2277 * Construct a v1 version string.
2278 */
a7d4653a 2279 verstring = dupprintf("SSH-%s-%s\012",
d38d6a1f 2280 (ssh_versioncmp(s->version, "1.5") <= 0 ?
2281 s->version : "1.5"),
2282 sshver);
2283 ssh->version = 1;
2284 }
2285
2286 ssh_fix_verstring(verstring);
2287
2288 if (ssh->version == 2) {
2289 /*
2290 * Hash our version string and their version string.
2291 */
2292 SHA_Init(&ssh->exhashbase);
0b351b6b 2293 sha_string(&ssh->exhashbase, verstring,
a7d4653a 2294 strcspn(verstring, "\015\012"));
0b351b6b 2295 sha_string(&ssh->exhashbase, s->vstring,
a7d4653a 2296 strcspn(s->vstring, "\015\012"));
d38d6a1f 2297
2298 /*
2299 * Initialise SSHv2 protocol.
2300 */
2301 ssh->protocol = ssh2_protocol;
2302 ssh2_protocol_setup(ssh);
2303 ssh->s_rdpkt = ssh2_rdpkt;
2304 } else {
2305 /*
2306 * Initialise SSHv1 protocol.
2307 */
2308 ssh->protocol = ssh1_protocol;
2309 ssh1_protocol_setup(ssh);
2310 ssh->s_rdpkt = ssh1_rdpkt;
2311 }
2312 logeventf(ssh, "We claim version: %.*s",
a7d4653a 2313 strcspn(verstring, "\015\012"), verstring);
51470298 2314 sk_write(ssh->s, verstring, strlen(verstring));
d38d6a1f 2315 sfree(verstring);
e5574168 2316 }
d38d6a1f 2317
2318 logeventf(ssh, "Using SSH protocol version %d", ssh->version);
2319
125105d1 2320 update_specials_menu(ssh->frontend);
51470298 2321 ssh->state = SSH_STATE_BEFORE_SIZE;
39934deb 2322 ssh->pinger = pinger_new(&ssh->cfg, &ssh_backend, ssh);
8df7a775 2323
51470298 2324 sfree(s->vstring);
50526e47 2325
8df7a775 2326 crFinish(0);
2327}
2328
51470298 2329static void ssh_gotdata(Ssh ssh, unsigned char *data, int datalen)
8df7a775 2330{
51470298 2331 crBegin(ssh->ssh_gotdata_crstate);
8df7a775 2332
2333 /*
2334 * To begin with, feed the characters one by one to the
2335 * protocol initialisation / selection function do_ssh_init().
2336 * When that returns 0, we're done with the initial greeting
2337 * exchange and can move on to packet discipline.
2338 */
2339 while (1) {
51470298 2340 int ret; /* need not be kept across crReturn */
8df7a775 2341 if (datalen == 0)
2342 crReturnV; /* more data please */
51470298 2343 ret = do_ssh_init(ssh, *data);
32874aea 2344 data++;
2345 datalen--;
8df7a775 2346 if (ret == 0)
2347 break;
2348 }
2349
2350 /*
2351 * We emerge from that loop when the initial negotiation is
2352 * over and we have selected an s_rdpkt function. Now pass
2353 * everything to s_rdpkt, and then pass the resulting packets
2354 * to the proper protocol handler.
2355 */
2356 if (datalen == 0)
2357 crReturnV;
2358 while (1) {
2359 while (datalen > 0) {
ff3187f6 2360 struct Packet *pktin = ssh->s_rdpkt(ssh, &data, &datalen);
2361 if (pktin) {
2362 ssh->protocol(ssh, NULL, 0, pktin);
2363 ssh_free_packet(pktin);
8df7a775 2364 }
ff3187f6 2365 if (ssh->state == SSH_STATE_CLOSED)
2366 return;
8df7a775 2367 }
2368 crReturnV;
2369 }
2370 crFinishV;
2371}
2372
ac934965 2373static int ssh_do_close(Ssh ssh, int notify_exit)
32874aea 2374{
ac934965 2375 int i, ret = 0;
36f94d1f 2376 struct ssh_channel *c;
2377
51470298 2378 ssh->state = SSH_STATE_CLOSED;
2379 if (ssh->s) {
2380 sk_close(ssh->s);
2381 ssh->s = NULL;
ac934965 2382 if (notify_exit)
2383 notify_remote_exit(ssh->frontend);
2384 else
2385 ret = 1;
f3ab576e 2386 }
36f94d1f 2387 /*
2388 * Now we must shut down any port and X forwardings going
2389 * through this connection.
2390 */
74a98066 2391 if (ssh->channels) {
2392 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
2393 switch (c->type) {
2394 case CHAN_X11:
2395 x11_close(c->u.x11.s);
2396 break;
2397 case CHAN_SOCKDATA:
2398 pfd_close(c->u.pfd.s);
2399 break;
2400 }
2401 del234(ssh->channels, c);
2402 if (ssh->version == 2)
2403 bufchain_clear(&c->v.v2.outbuffer);
2404 sfree(c);
36f94d1f 2405 }
36f94d1f 2406 }
ac934965 2407
2408 return ret;
36f94d1f 2409}
2410
cbe2d68f 2411static int ssh_closing(Plug plug, const char *error_msg, int error_code,
36f94d1f 2412 int calling_back)
2413{
2414 Ssh ssh = (Ssh) plug;
ac934965 2415 int need_notify = ssh_do_close(ssh, FALSE);
2416
2417 if (!error_msg && !ssh->close_expected) {
2418 error_msg = "Server unexpectedly closed network connection";
2419 }
2420
7e78000d 2421 if (error_msg) {
32874aea 2422 /* A socket error has occurred. */
247308b5 2423 logevent(error_msg);
971bcc0a 2424 connection_fatal(ssh->frontend, "%s", error_msg);
7e78000d 2425 } else {
ac934965 2426 logevent("Server closed network connection");
8df7a775 2427 }
ac934965 2428 if (need_notify)
2429 notify_remote_exit(ssh->frontend);
7e78000d 2430 return 0;
2431}
2432
32874aea 2433static int ssh_receive(Plug plug, int urgent, char *data, int len)
2434{
51470298 2435 Ssh ssh = (Ssh) plug;
d8baa528 2436 ssh_gotdata(ssh, (unsigned char *)data, len);
51470298 2437 if (ssh->state == SSH_STATE_CLOSED) {
ac934965 2438 ssh_do_close(ssh, TRUE);
32874aea 2439 return 0;
3257deae 2440 }
fef97f43 2441 return 1;
374330e2 2442}
2443
5471d09a 2444static void ssh_sent(Plug plug, int bufsize)
2445{
51470298 2446 Ssh ssh = (Ssh) plug;
5471d09a 2447 /*
2448 * If the send backlog on the SSH socket itself clears, we
2449 * should unthrottle the whole world if it was throttled.
2450 */
2451 if (bufsize < SSH_MAX_BACKLOG)
51470298 2452 ssh_throttle_all(ssh, 0, bufsize);
5471d09a 2453}
2454
fb09bf1c 2455/*
8df7a775 2456 * Connect to specified host and port.
2457 * Returns an error message, or NULL on success.
6e1ebb76 2458 * Also places the canonical host name into `realhost'. It must be
2459 * freed by the caller.
8df7a775 2460 */
cbe2d68f 2461static const char *connect_to_host(Ssh ssh, char *host, int port,
79bf227b 2462 char **realhost, int nodelay, int keepalive)
8df7a775 2463{
51470298 2464 static const struct plug_function_table fn_table = {
7e78000d 2465 ssh_closing,
5471d09a 2466 ssh_receive,
2467 ssh_sent,
2468 NULL
51470298 2469 };
7e78000d 2470
8df7a775 2471 SockAddr addr;
cbe2d68f 2472 const char *err;
8df7a775 2473
3d88e64d 2474 ssh->savedhost = snewn(1 + strlen(host), char);
51470298 2475 if (!ssh->savedhost)
8df7a775 2476 fatalbox("Out of memory");
51470298 2477 strcpy(ssh->savedhost, host);
8df7a775 2478
2479 if (port < 0)
2480 port = 22; /* default ssh port */
51470298 2481 ssh->savedport = port;
8df7a775 2482
2483 /*
2484 * Try to find host.
2485 */
05581745 2486 logeventf(ssh, "Looking up host \"%s\"%s", host,
2487 (ssh->cfg.addressfamily == ADDRTYPE_IPV4 ? " (IPv4)" :
2488 (ssh->cfg.addressfamily == ADDRTYPE_IPV6 ? " (IPv6)" : "")));
2489 addr = name_lookup(host, port, realhost, &ssh->cfg,
2490 ssh->cfg.addressfamily);
170c1e6e 2491 if ((err = sk_addr_error(addr)) != NULL) {
2492 sk_addr_free(addr);
8df7a775 2493 return err;
170c1e6e 2494 }
8df7a775 2495
8df7a775 2496 /*
2497 * Open socket.
2498 */
3ad9d396 2499 {
57356d63 2500 char addrbuf[100];
3ad9d396 2501 sk_getaddr(addr, addrbuf, 100);
57356d63 2502 logeventf(ssh, "Connecting to %s port %d", addrbuf, port);
3ad9d396 2503 }
51470298 2504 ssh->fn = &fn_table;
e8fa8f62 2505 ssh->s = new_connection(addr, *realhost, port,
79bf227b 2506 0, 1, nodelay, keepalive, (Plug) ssh, &ssh->cfg);
70e5d0fd 2507 if ((err = sk_socket_error(ssh->s)) != NULL) {
51470298 2508 ssh->s = NULL;
39934deb 2509 notify_remote_exit(ssh->frontend);
8df7a775 2510 return err;
67c4ba2e 2511 }
8df7a775 2512
8df7a775 2513 return NULL;
2514}
2515
2516/*
5471d09a 2517 * Throttle or unthrottle the SSH connection.
2518 */
51470298 2519static void ssh1_throttle(Ssh ssh, int adjust)
5471d09a 2520{
51470298 2521 int old_count = ssh->v1_throttle_count;
2522 ssh->v1_throttle_count += adjust;
2523 assert(ssh->v1_throttle_count >= 0);
2524 if (ssh->v1_throttle_count && !old_count) {
2525 sk_set_frozen(ssh->s, 1);
2526 } else if (!ssh->v1_throttle_count && old_count) {
2527 sk_set_frozen(ssh->s, 0);
5471d09a 2528 }
2529}
2530
2531/*
2532 * Throttle or unthrottle _all_ local data streams (for when sends
2533 * on the SSH connection itself back up).
2534 */
51470298 2535static void ssh_throttle_all(Ssh ssh, int enable, int bufsize)
5471d09a 2536{
2537 int i;
2538 struct ssh_channel *c;
2539
51470298 2540 if (enable == ssh->throttled_all)
5471d09a 2541 return;
51470298 2542 ssh->throttled_all = enable;
2543 ssh->overall_bufsize = bufsize;
2544 if (!ssh->channels)
5471d09a 2545 return;
51470298 2546 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
5471d09a 2547 switch (c->type) {
2548 case CHAN_MAINSESSION:
2549 /*
2550 * This is treated separately, outside the switch.
2551 */
2552 break;
2553 case CHAN_X11:
2554 x11_override_throttle(c->u.x11.s, enable);
2555 break;
2556 case CHAN_AGENT:
2557 /* Agent channels require no buffer management. */
2558 break;
2559 case CHAN_SOCKDATA:
36f94d1f 2560 pfd_override_throttle(c->u.pfd.s, enable);
5471d09a 2561 break;
2562 }
2563 }
2564}
2565
2566/*
51470298 2567 * Username and password input, abstracted off into routines
2568 * reusable in several places - even between SSH1 and SSH2.
0405e71f 2569 */
0405e71f 2570
2571/* Set up a username or password input loop on a given buffer. */
ae9ae89f 2572static void setup_userpass_input(Ssh ssh, char *buffer, int buflen, int echo)
0405e71f 2573{
51470298 2574 ssh->userpass_input_buffer = buffer;
2575 ssh->userpass_input_buflen = buflen;
2576 ssh->userpass_input_bufpos = 0;
2577 ssh->userpass_input_echo = echo;
0405e71f 2578}
2579
2580/*
2581 * Process some terminal data in the course of username/password
2582 * input. Returns >0 for success (line of input returned in
2583 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2584 * for inconclusive (keep waiting for more input please).
2585 */
ae9ae89f 2586static int process_userpass_input(Ssh ssh, unsigned char *in, int inlen)
0405e71f 2587{
2588 char c;
2589
2590 while (inlen--) {
2591 switch (c = *in++) {
2592 case 10:
2593 case 13:
51470298 2594 ssh->userpass_input_buffer[ssh->userpass_input_bufpos] = 0;
2595 ssh->userpass_input_buffer[ssh->userpass_input_buflen-1] = 0;
0405e71f 2596 return +1;
2597 break;
2598 case 8:
2599 case 127:
51470298 2600 if (ssh->userpass_input_bufpos > 0) {
2601 if (ssh->userpass_input_echo)
2602 c_write_str(ssh, "\b \b");
2603 ssh->userpass_input_bufpos--;
0405e71f 2604 }
2605 break;
2606 case 21:
2607 case 27:
51470298 2608 while (ssh->userpass_input_bufpos > 0) {
2609 if (ssh->userpass_input_echo)
2610 c_write_str(ssh, "\b \b");
2611 ssh->userpass_input_bufpos--;
0405e71f 2612 }
2613 break;
2614 case 3:
2615 case 4:
2616 return -1;
2617 break;
2618 default:
4692a14a 2619 /*
2620 * This simplistic check for printability is disabled
2621 * when we're doing password input, because some people
2622 * have control characters in their passwords.o
2623 */
2624 if ((!ssh->userpass_input_echo ||
2625 (c >= ' ' && c <= '~') ||
0405e71f 2626 ((unsigned char) c >= 160))
51470298 2627 && ssh->userpass_input_bufpos < ssh->userpass_input_buflen-1) {
2628 ssh->userpass_input_buffer[ssh->userpass_input_bufpos++] = c;
2629 if (ssh->userpass_input_echo)
2630 c_write(ssh, &c, 1);
0405e71f 2631 }
2632 break;
2633 }
2634 }
2635 return 0;
2636}
2637
f11d78f2 2638static void ssh_agent_callback(void *sshv, void *reply, int replylen)
839f10db 2639{
2640 Ssh ssh = (Ssh) sshv;
2641
2642 ssh->agent_response = reply;
2643 ssh->agent_response_len = replylen;
2644
2645 if (ssh->version == 1)
ff3187f6 2646 do_ssh1_login(ssh, NULL, -1, NULL);
839f10db 2647 else
ff3187f6 2648 do_ssh2_authconn(ssh, NULL, -1, NULL);
839f10db 2649}
2650
f11d78f2 2651static void ssh_agentf_callback(void *cv, void *reply, int replylen)
839f10db 2652{
2653 struct ssh_channel *c = (struct ssh_channel *)cv;
2654 Ssh ssh = c->ssh;
2655 void *sentreply = reply;
2656
2657 if (!sentreply) {
2658 /* Fake SSH_AGENT_FAILURE. */
2659 sentreply = "\0\0\0\1\5";
2660 replylen = 5;
2661 }
2662 if (ssh->version == 2) {
2663 ssh2_add_channel_data(c, sentreply, replylen);
2664 ssh2_try_send(c);
2665 } else {
2666 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
2667 PKT_INT, c->remoteid,
9a10ecf4 2668 PKTT_DATA,
839f10db 2669 PKT_INT, replylen,
2670 PKT_DATA, sentreply, replylen,
9a10ecf4 2671 PKTT_OTHER,
839f10db 2672 PKT_END);
2673 }
2674 if (reply)
2675 sfree(reply);
2676}
2677
0405e71f 2678/*
fb09bf1c 2679 * Handle the key exchange and user authentication phases.
2680 */
ff3187f6 2681static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen,
2682 struct Packet *pktin)
fb09bf1c 2683{
0016d70b 2684 int i, j, ret;
2685 unsigned char cookie[8], *ptr;
374330e2 2686 struct RSAKey servkey, hostkey;
2687 struct MD5Context md5c;
51470298 2688 struct do_ssh1_login_state {
2689 int len;
2690 unsigned char *rsabuf, *keystr1, *keystr2;
2691 unsigned long supported_ciphers_mask, supported_auths_mask;
2692 int tried_publickey, tried_agent;
2693 int tis_auth_refused, ccard_auth_refused;
2694 unsigned char session_id[16];
2695 int cipher_type;
2696 char username[100];
2697 void *publickey_blob;
2698 int publickey_bloblen;
2699 char password[100];
2700 char prompt[200];
2701 int pos;
2702 char c;
2703 int pwpkt_type;
2704 unsigned char request[5], *response, *p;
2705 int responselen;
2706 int keyi, nkeys;
2707 int authed;
2708 struct RSAKey key;
2709 Bignum challenge;
2710 char *commentp;
2711 int commentlen;
2712 };
2713 crState(do_ssh1_login_state);
2714
2715 crBegin(ssh->do_ssh1_login_crstate);
374330e2 2716
ff3187f6 2717 if (!pktin)
2718 crWaitUntil(pktin);
374330e2 2719
ff3187f6 2720 if (pktin->type != SSH1_SMSG_PUBLIC_KEY) {
6b5cf8b4 2721 bombout(("Public key packet not received"));
7ffdbc1a 2722 crStop(0);
8d5de777 2723 }
374330e2 2724
c5e9c988 2725 logevent("Received public keys");
374330e2 2726
ff3187f6 2727 ptr = ssh_pkt_getdata(pktin, 8);
0016d70b 2728 if (!ptr) {
2729 bombout(("SSH1 public key packet stopped before random cookie"));
2730 crStop(0);
2731 }
2732 memcpy(cookie, ptr, 8);
374330e2 2733
ff3187f6 2734 if (!ssh1_pkt_getrsakey(pktin, &servkey, &s->keystr1) ||
2735 !ssh1_pkt_getrsakey(pktin, &hostkey, &s->keystr2)) {
ae0500e5 2736 bombout(("Failed to read SSH1 public keys from public key packet"));
0016d70b 2737 crStop(0);
2738 }
374330e2 2739
c5e9c988 2740 /*
1c2a93c4 2741 * Log the host key fingerprint.
c5e9c988 2742 */
c5e9c988 2743 {
2744 char logmsg[80];
1c2a93c4 2745 logevent("Host key fingerprint is:");
c5e9c988 2746 strcpy(logmsg, " ");
32874aea 2747 hostkey.comment = NULL;
2748 rsa_fingerprint(logmsg + strlen(logmsg),
2749 sizeof(logmsg) - strlen(logmsg), &hostkey);
c5e9c988 2750 logevent(logmsg);
2751 }
2752
ff3187f6 2753 ssh->v1_remote_protoflags = ssh_pkt_getuint32(pktin);
2754 s->supported_ciphers_mask = ssh_pkt_getuint32(pktin);
2755 s->supported_auths_mask = ssh_pkt_getuint32(pktin);
bea1ef5f 2756
51470298 2757 ssh->v1_local_protoflags =
2758 ssh->v1_remote_protoflags & SSH1_PROTOFLAGS_SUPPORTED;
2759 ssh->v1_local_protoflags |= SSH1_PROTOFLAG_SCREEN_NUMBER;
b96dc54c 2760
c5e9c988 2761 MD5Init(&md5c);
51470298 2762 MD5Update(&md5c, s->keystr2, hostkey.bytes);
2763 MD5Update(&md5c, s->keystr1, servkey.bytes);
0016d70b 2764 MD5Update(&md5c, cookie, 8);
51470298 2765 MD5Final(s->session_id, &md5c);
374330e2 2766
32874aea 2767 for (i = 0; i < 32; i++)
51470298 2768 ssh->session_key[i] = random_byte();
374330e2 2769
0016d70b 2770 /*
2771 * Verify that the `bits' and `bytes' parameters match.
2772 */
2773 if (hostkey.bits > hostkey.bytes * 8 ||
2774 servkey.bits > servkey.bytes * 8) {
2775 bombout(("SSH1 public keys were badly formatted"));
2776 crStop(0);
2777 }
2778
51470298 2779 s->len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
374330e2 2780
3d88e64d 2781 s->rsabuf = snewn(s->len, unsigned char);
51470298 2782 if (!s->rsabuf)
374330e2 2783 fatalbox("Out of memory");
2784
89ee5268 2785 /*
2786 * Verify the host key.
2787 */
2788 {
32874aea 2789 /*
2790 * First format the key into a string.
2791 */
2792 int len = rsastr_len(&hostkey);
2793 char fingerprint[100];
3d88e64d 2794 char *keystr = snewn(len, char);
32874aea 2795 if (!keystr)
2796 fatalbox("Out of memory");
2797 rsastr_fmt(keystr, &hostkey);
2798 rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
a8327734 2799 verify_ssh_host_key(ssh->frontend,
2800 ssh->savedhost, ssh->savedport, "rsa", keystr,
32874aea 2801 fingerprint);
2802 sfree(keystr);
2803 }
2804
2805 for (i = 0; i < 32; i++) {
51470298 2806 s->rsabuf[i] = ssh->session_key[i];
374330e2 2807 if (i < 16)
51470298 2808 s->rsabuf[i] ^= s->session_id[i];
374330e2 2809 }
2810
2811 if (hostkey.bytes > servkey.bytes) {
0016d70b 2812 ret = rsaencrypt(s->rsabuf, 32, &servkey);
2813 if (ret)
2814 ret = rsaencrypt(s->rsabuf, servkey.bytes, &hostkey);
374330e2 2815 } else {
0016d70b 2816 ret = rsaencrypt(s->rsabuf, 32, &hostkey);
2817 if (ret)
2818 ret = rsaencrypt(s->rsabuf, hostkey.bytes, &servkey);
2819 }
2820 if (!ret) {
2821 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2822 crStop(0);
374330e2 2823 }
2824
c5e9c988 2825 logevent("Encrypted session key");
2826
ca20bfcf 2827 {
2828 int cipher_chosen = 0, warn = 0;
2829 char *cipher_string = NULL;
51470298 2830 int i;
ca20bfcf 2831 for (i = 0; !cipher_chosen && i < CIPHER_MAX; i++) {
86916870 2832 int next_cipher = ssh->cfg.ssh_cipherlist[i];
ca20bfcf 2833 if (next_cipher == CIPHER_WARN) {
2834 /* If/when we choose a cipher, warn about it */
2835 warn = 1;
2836 } else if (next_cipher == CIPHER_AES) {
2837 /* XXX Probably don't need to mention this. */
2838 logevent("AES not supported in SSH1, skipping");
2839 } else {
2840 switch (next_cipher) {
51470298 2841 case CIPHER_3DES: s->cipher_type = SSH_CIPHER_3DES;
ca20bfcf 2842 cipher_string = "3DES"; break;
51470298 2843 case CIPHER_BLOWFISH: s->cipher_type = SSH_CIPHER_BLOWFISH;
ca20bfcf 2844 cipher_string = "Blowfish"; break;
51470298 2845 case CIPHER_DES: s->cipher_type = SSH_CIPHER_DES;
ca20bfcf 2846 cipher_string = "single-DES"; break;
2847 }
51470298 2848 if (s->supported_ciphers_mask & (1 << s->cipher_type))
ca20bfcf 2849 cipher_chosen = 1;
2850 }
2851 }
2852 if (!cipher_chosen) {
51470298 2853 if ((s->supported_ciphers_mask & (1 << SSH_CIPHER_3DES)) == 0)
6b5cf8b4 2854 bombout(("Server violates SSH 1 protocol by not "
ca20bfcf 2855 "supporting 3DES encryption"));
2856 else
2857 /* shouldn't happen */
6b5cf8b4 2858 bombout(("No supported ciphers found"));
7ffdbc1a 2859 crStop(0);
a99a05c0 2860 }
ca20bfcf 2861
2862 /* Warn about chosen cipher if necessary. */
bb348ab1 2863 if (warn) {
2864 sk_set_frozen(ssh->s, 1);
83e7d008 2865 askalg(ssh->frontend, "cipher", cipher_string);
bb348ab1 2866 sk_set_frozen(ssh->s, 0);
2867 }
bea1ef5f 2868 }
ca20bfcf 2869
51470298 2870 switch (s->cipher_type) {
32874aea 2871 case SSH_CIPHER_3DES:
2872 logevent("Using 3DES encryption");
2873 break;
2874 case SSH_CIPHER_DES:
2875 logevent("Using single-DES encryption");
2876 break;
2877 case SSH_CIPHER_BLOWFISH:
2878 logevent("Using Blowfish encryption");
2879 break;
c5e9c988 2880 }
bea1ef5f 2881
51470298 2882 send_packet(ssh, SSH1_CMSG_SESSION_KEY,
2883 PKT_CHAR, s->cipher_type,
32874aea 2884 PKT_DATA, cookie, 8,
51470298 2885 PKT_CHAR, (s->len * 8) >> 8, PKT_CHAR, (s->len * 8) & 0xFF,
2886 PKT_DATA, s->rsabuf, s->len,
2887 PKT_INT, ssh->v1_local_protoflags, PKT_END);
fb09bf1c 2888
c5e9c988 2889 logevent("Trying to enable encryption...");
374330e2 2890
51470298 2891 sfree(s->rsabuf);
374330e2 2892
51470298 2893 ssh->cipher = (s->cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
2894 s->cipher_type == SSH_CIPHER_DES ? &ssh_des :
2895 &ssh_3des);
371e569c 2896 ssh->v1_cipher_ctx = ssh->cipher->make_context();
2897 ssh->cipher->sesskey(ssh->v1_cipher_ctx, ssh->session_key);
57356d63 2898 logeventf(ssh, "Initialised %s encryption", ssh->cipher->text_name);
374330e2 2899
0183b242 2900 ssh->crcda_ctx = crcda_make_context();
2901 logevent("Installing CRC compensation attack detector");
2902
679539d7 2903 if (servkey.modulus) {
2904 sfree(servkey.modulus);
2905 servkey.modulus = NULL;
2906 }
2907 if (servkey.exponent) {
2908 sfree(servkey.exponent);
2909 servkey.exponent = NULL;
2910 }
2911 if (hostkey.modulus) {
2912 sfree(hostkey.modulus);
2913 hostkey.modulus = NULL;
2914 }
2915 if (hostkey.exponent) {
2916 sfree(hostkey.exponent);
2917 hostkey.exponent = NULL;
2918 }
ff3187f6 2919 crWaitUntil(pktin);
374330e2 2920
ff3187f6 2921 if (pktin->type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 2922 bombout(("Encryption not successfully enabled"));
7ffdbc1a 2923 crStop(0);
8d5de777 2924 }
374330e2 2925
c5e9c988 2926 logevent("Successfully started encryption");
2927
374330e2 2928 fflush(stdout);
2929 {
aa09f7d0 2930 if (!*ssh->cfg.username) {
c0a81592 2931 if (ssh_get_line && !ssh_getline_pw_only) {
32874aea 2932 if (!ssh_get_line("login as: ",
51470298 2933 s->username, sizeof(s->username), FALSE)) {
32874aea 2934 /*
2935 * get_line failed to get a username.
2936 * Terminate.
2937 */
2938 logevent("No username provided. Abandoning session.");
ac934965 2939 ssh->close_expected = TRUE;
3bb2f322 2940 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 2941 crStop(1);
32874aea 2942 }
2943 } else {
51470298 2944 int ret; /* need not be kept over crReturn */
2945 c_write_str(ssh, "login as: ");
2946 ssh->send_ok = 1;
0405e71f 2947
51470298 2948 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
0405e71f 2949 do {
ff3187f6 2950 crWaitUntil(!pktin);
51470298 2951 ret = process_userpass_input(ssh, in, inlen);
0405e71f 2952 } while (ret == 0);
2953 if (ret < 0)
2954 cleanup_exit(0);
51470298 2955 c_write_str(ssh, "\r\n");
32874aea 2956 }
2957 } else {
86916870 2958 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
51470298 2959 s->username[sizeof(s->username)-1] = '\0';
374330e2 2960 }
fb09bf1c 2961
51470298 2962 send_packet(ssh, SSH1_CMSG_USER, PKT_STR, s->username, PKT_END);
c5e9c988 2963 {
51470298 2964 char userlog[22 + sizeof(s->username)];
2965 sprintf(userlog, "Sent username \"%s\"", s->username);
c5e9c988 2966 logevent(userlog);
32874aea 2967 if (flags & FLAG_INTERACTIVE &&
2968 (!((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)))) {
3c8e959b 2969 strcat(userlog, "\r\n");
51470298 2970 c_write_str(ssh, userlog);
3c8e959b 2971 }
c5e9c988 2972 }
374330e2 2973 }
2974
ff3187f6 2975 crWaitUntil(pktin);
374330e2 2976
51470298 2977 if ((ssh->remote_bugs & BUG_CHOKES_ON_RSA)) {
0df73905 2978 /* We must not attempt PK auth. Pretend we've already tried it. */
51470298 2979 s->tried_publickey = s->tried_agent = 1;
0df73905 2980 } else {
51470298 2981 s->tried_publickey = s->tried_agent = 0;
0df73905 2982 }
51470298 2983 s->tis_auth_refused = s->ccard_auth_refused = 0;
86916870 2984 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
9a30e26b 2985 if (!filename_is_null(ssh->cfg.keyfile)) {
2986 if (!rsakey_pubblob(&ssh->cfg.keyfile,
222d54dc 2987 &s->publickey_blob, &s->publickey_bloblen, NULL))
51470298 2988 s->publickey_blob = NULL;
396778f1 2989 } else
51470298 2990 s->publickey_blob = NULL;
7cca0d81 2991
ff3187f6 2992 while (pktin->type == SSH1_SMSG_FAILURE) {
51470298 2993 s->pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
614a20a0 2994
51470298 2995 if (agent_exists() && !s->tried_agent) {
32874aea 2996 /*
2997 * Attempt RSA authentication using Pageant.
2998 */
32874aea 2999 void *r;
3000
51470298 3001 s->authed = FALSE;
3002 s->tried_agent = 1;
32874aea 3003 logevent("Pageant is running. Requesting keys.");
3004
3005 /* Request the keys held by the agent. */
51470298 3006 PUT_32BIT(s->request, 1);
3007 s->request[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES;
839f10db 3008 if (!agent_query(s->request, 5, &r, &s->responselen,
3009 ssh_agent_callback, ssh)) {
3010 do {
3011 crReturn(0);
ff3187f6 3012 if (pktin) {
839f10db 3013 bombout(("Unexpected data from server while waiting"
3014 " for agent response"));
3015 crStop(0);
3016 }
ff3187f6 3017 } while (pktin || inlen > 0);
839f10db 3018 r = ssh->agent_response;
3019 s->responselen = ssh->agent_response_len;
3020 }
51470298 3021 s->response = (unsigned char *) r;
3022 if (s->response && s->responselen >= 5 &&
3023 s->response[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER) {
3024 s->p = s->response + 5;
3025 s->nkeys = GET_32BIT(s->p);
3026 s->p += 4;
32874aea 3027 {
3028 char buf[64];
51470298 3029 sprintf(buf, "Pageant has %d SSH1 keys", s->nkeys);
32874aea 3030 logevent(buf);
3031 }
51470298 3032 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
32874aea 3033 {
3034 char buf[64];
51470298 3035 sprintf(buf, "Trying Pageant key #%d", s->keyi);
32874aea 3036 logevent(buf);
3037 }
51470298 3038 if (s->publickey_blob &&
3039 !memcmp(s->p, s->publickey_blob,
3040 s->publickey_bloblen)) {
396778f1 3041 logevent("This key matches configured key file");
51470298 3042 s->tried_publickey = 1;
396778f1 3043 }
51470298 3044 s->p += 4;
0016d70b 3045 {
3046 int n, ok = FALSE;
3047 do { /* do while (0) to make breaking easy */
3048 n = ssh1_read_bignum
3049 (s->p, s->responselen-(s->p-s->response),
3050 &s->key.exponent);
3051 if (n < 0)
3052 break;
3053 s->p += n;
3054 n = ssh1_read_bignum
3055 (s->p, s->responselen-(s->p-s->response),
3056 &s->key.modulus);
3057 if (n < 0)
3058 break;
3059 s->p += n;
3060 if (s->responselen - (s->p-s->response) < 4)
3061 break;
3062 s->commentlen = GET_32BIT(s->p);
3063 s->p += 4;
3064 if (s->responselen - (s->p-s->response) <
3065 s->commentlen)
3066 break;
3067 s->commentp = (char *)s->p;
3068 s->p += s->commentlen;
3069 ok = TRUE;
3070 } while (0);
3071 if (!ok) {
3072 logevent("Pageant key list packet was truncated");
3073 break;
3074 }
3075 }
51470298 3076 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
3077 PKT_BIGNUM, s->key.modulus, PKT_END);
ff3187f6 3078 crWaitUntil(pktin);
3079 if (pktin->type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
32874aea 3080 logevent("Key refused");
3081 continue;
3082 }
3083 logevent("Received RSA challenge");
ff3187f6 3084 if ((s->challenge = ssh1_pkt_getmp(pktin)) == NULL) {
0016d70b 3085 bombout(("Server's RSA challenge was badly formatted"));
3086 crStop(0);
3087 }
3088
32874aea 3089 {
3090 char *agentreq, *q, *ret;
2d466ffd 3091 void *vret;
32874aea 3092 int len, retlen;
3093 len = 1 + 4; /* message type, bit count */
51470298 3094 len += ssh1_bignum_length(s->key.exponent);
3095 len += ssh1_bignum_length(s->key.modulus);
3096 len += ssh1_bignum_length(s->challenge);
32874aea 3097 len += 16; /* session id */
3098 len += 4; /* response format */
3d88e64d 3099 agentreq = snewn(4 + len, char);
32874aea 3100 PUT_32BIT(agentreq, len);
3101 q = agentreq + 4;
3102 *q++ = SSH1_AGENTC_RSA_CHALLENGE;
51470298 3103 PUT_32BIT(q, bignum_bitcount(s->key.modulus));
32874aea 3104 q += 4;
51470298 3105 q += ssh1_write_bignum(q, s->key.exponent);
3106 q += ssh1_write_bignum(q, s->key.modulus);
3107 q += ssh1_write_bignum(q, s->challenge);
3108 memcpy(q, s->session_id, 16);
32874aea 3109 q += 16;
3110 PUT_32BIT(q, 1); /* response format */
839f10db 3111 if (!agent_query(agentreq, len + 4, &vret, &retlen,
3112 ssh_agent_callback, ssh)) {
3113 sfree(agentreq);
3114 do {
3115 crReturn(0);
ff3187f6 3116 if (pktin) {
839f10db 3117 bombout(("Unexpected data from server"
3118 " while waiting for agent"
3119 " response"));
3120 crStop(0);
3121 }
ff3187f6 3122 } while (pktin || inlen > 0);
839f10db 3123 vret = ssh->agent_response;
3124 retlen = ssh->agent_response_len;
3125 } else
3126 sfree(agentreq);
2d466ffd 3127 ret = vret;
32874aea 3128 if (ret) {
3129 if (ret[4] == SSH1_AGENT_RSA_RESPONSE) {
3130 logevent("Sending Pageant's response");
51470298 3131 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
32874aea 3132 PKT_DATA, ret + 5, 16,
3133 PKT_END);
3134 sfree(ret);
ff3187f6 3135 crWaitUntil(pktin);
3136 if (pktin->type == SSH1_SMSG_SUCCESS) {
32874aea 3137 logevent
3138 ("Pageant's response accepted");
3139 if (flags & FLAG_VERBOSE) {
51470298 3140 c_write_str(ssh, "Authenticated using"
3141 " RSA key \"");
3142 c_write(ssh, s->commentp,
3143 s->commentlen);
3144 c_write_str(ssh, "\" from agent\r\n");
32874aea 3145 }
51470298 3146 s->authed = TRUE;
32874aea 3147 } else
3148 logevent
3149 ("Pageant's response not accepted");
3150 } else {
3151 logevent
3152 ("Pageant failed to answer challenge");
3153 sfree(ret);
3154 }
3155 } else {
3156 logevent("No reply received from Pageant");
3157 }
3158 }
51470298 3159 freebn(s->key.exponent);
3160 freebn(s->key.modulus);
3161 freebn(s->challenge);
3162 if (s->authed)
32874aea 3163 break;
3164 }
29b1d0b3 3165 sfree(s->response);
32874aea 3166 }
51470298 3167 if (s->authed)
32874aea 3168 break;
3169 }
9a30e26b 3170 if (!filename_is_null(ssh->cfg.keyfile) && !s->tried_publickey)
51470298 3171 s->pwpkt_type = SSH1_CMSG_AUTH_RSA;
32874aea 3172
86916870 3173 if (ssh->cfg.try_tis_auth &&
51470298 3174 (s->supported_auths_mask & (1 << SSH1_AUTH_TIS)) &&
3175 !s->tis_auth_refused) {
3176 s->pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
32874aea 3177 logevent("Requested TIS authentication");
51470298 3178 send_packet(ssh, SSH1_CMSG_AUTH_TIS, PKT_END);
ff3187f6 3179 crWaitUntil(pktin);
3180 if (pktin->type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
32874aea 3181 logevent("TIS authentication declined");
3182 if (flags & FLAG_INTERACTIVE)
51470298 3183 c_write_str(ssh, "TIS authentication refused.\r\n");
3184 s->tis_auth_refused = 1;
614a20a0 3185 continue;
32874aea 3186 } else {
0016d70b 3187 char *challenge;
3188 int challengelen;
3189
ff3187f6 3190 ssh_pkt_getstring(pktin, &challenge, &challengelen);
0016d70b 3191 if (!challenge) {
3192 bombout(("TIS challenge packet was badly formed"));
3193 crStop(0);
3194 }
32874aea 3195 logevent("Received TIS challenge");
51470298 3196 if (challengelen > sizeof(s->prompt) - 1)
3197 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
0016d70b 3198 memcpy(s->prompt, challenge, challengelen);
614a20a0 3199 /* Prompt heuristic comes from OpenSSH */
51470298 3200 strncpy(s->prompt + challengelen,
3201 memchr(s->prompt, '\n', challengelen) ?
614a20a0 3202 "": "\r\nResponse: ",
51470298 3203 (sizeof s->prompt) - challengelen);
3204 s->prompt[(sizeof s->prompt) - 1] = '\0';
32874aea 3205 }
3206 }
86916870 3207 if (ssh->cfg.try_tis_auth &&
51470298 3208 (s->supported_auths_mask & (1 << SSH1_AUTH_CCARD)) &&
3209 !s->ccard_auth_refused) {
3210 s->pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
32874aea 3211 logevent("Requested CryptoCard authentication");
51470298 3212 send_packet(ssh, SSH1_CMSG_AUTH_CCARD, PKT_END);
ff3187f6 3213 crWaitUntil(pktin);
3214 if (pktin->type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
32874aea 3215 logevent("CryptoCard authentication declined");
51470298 3216 c_write_str(ssh, "CryptoCard authentication refused.\r\n");
3217 s->ccard_auth_refused = 1;
614a20a0 3218 continue;
32874aea 3219 } else {
0016d70b 3220 char *challenge;
3221 int challengelen;
3222
ff3187f6 3223 ssh_pkt_getstring(pktin, &challenge, &challengelen);
0016d70b 3224 if (!challenge) {
3225 bombout(("CryptoCard challenge packet was badly formed"));
3226 crStop(0);
3227 }
32874aea 3228 logevent("Received CryptoCard challenge");
51470298 3229 if (challengelen > sizeof(s->prompt) - 1)
3230 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
0016d70b 3231 memcpy(s->prompt, challenge, challengelen);
51470298 3232 strncpy(s->prompt + challengelen,
3233 memchr(s->prompt, '\n', challengelen) ?
614a20a0 3234 "" : "\r\nResponse: ",
51470298 3235 sizeof(s->prompt) - challengelen);
3236 s->prompt[sizeof(s->prompt) - 1] = '\0';
32874aea 3237 }
3238 }
51470298 3239 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
3240 sprintf(s->prompt, "%.90s@%.90s's password: ",
3241 s->username, ssh->savedhost);
32874aea 3242 }
51470298 3243 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
32874aea 3244 char *comment = NULL;
231ee168 3245 int type;
3246 char msgbuf[256];
32874aea 3247 if (flags & FLAG_VERBOSE)
51470298 3248 c_write_str(ssh, "Trying public key authentication.\r\n");
6c6d9ed9 3249 logeventf(ssh, "Trying public key \"%s\"",
3250 filename_to_str(&ssh->cfg.keyfile));
9a30e26b 3251 type = key_type(&ssh->cfg.keyfile);
231ee168 3252 if (type != SSH_KEYTYPE_SSH1) {
3253 sprintf(msgbuf, "Key is of wrong type (%s)",
3254 key_type_to_str(type));
3255 logevent(msgbuf);
51470298 3256 c_write_str(ssh, msgbuf);
3257 c_write_str(ssh, "\r\n");
3258 s->tried_publickey = 1;
231ee168 3259 continue;
3260 }
9a30e26b 3261 if (!rsakey_encrypted(&ssh->cfg.keyfile, &comment)) {
32874aea 3262 if (flags & FLAG_VERBOSE)
51470298 3263 c_write_str(ssh, "No passphrase required.\r\n");
32874aea 3264 goto tryauth;
3265 }
51470298 3266 sprintf(s->prompt, "Passphrase for key \"%.100s\": ", comment);
32874aea 3267 sfree(comment);
3268 }
a52f067e 3269
614a20a0 3270 /*
3271 * Show password prompt, having first obtained it via a TIS
3272 * or CryptoCard exchange if we're doing TIS or CryptoCard
3273 * authentication.
3274 */
fa17a66e 3275 if (ssh_get_line) {
51470298 3276 if (!ssh_get_line(s->prompt, s->password,
3277 sizeof(s->password), TRUE)) {
32874aea 3278 /*
3279 * get_line failed to get a password (for example
3280 * because one was supplied on the command line
3281 * which has already failed to work). Terminate.
3282 */
51470298 3283 send_packet(ssh, SSH1_MSG_DISCONNECT,
2bc6a386 3284 PKT_STR, "No more passwords available to try",
3285 PKT_END);
247308b5 3286 logevent("Unable to authenticate");
a8327734 3287 connection_fatal(ssh->frontend, "Unable to authenticate");
ac934965 3288 ssh->close_expected = TRUE;
3bb2f322 3289 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 3290 crStop(1);
32874aea 3291 }
fb09bf1c 3292 } else {
614a20a0 3293 /* Prompt may have come from server. We've munged it a bit, so
3294 * we know it to be zero-terminated at least once. */
51470298 3295 int ret; /* need not be saved over crReturn */
3296 c_write_untrusted(ssh, s->prompt, strlen(s->prompt));
3297 s->pos = 0;
0405e71f 3298
51470298 3299 setup_userpass_input(ssh, s->password, sizeof(s->password), 0);
0405e71f 3300 do {
ff3187f6 3301 crWaitUntil(!pktin);
51470298 3302 ret = process_userpass_input(ssh, in, inlen);
0405e71f 3303 } while (ret == 0);
3304 if (ret < 0)
3305 cleanup_exit(0);
51470298 3306 c_write_str(ssh, "\r\n");
32874aea 3307 }
3308
3309 tryauth:
51470298 3310 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
32874aea 3311 /*
3312 * Try public key authentication with the specified
3313 * key file.
3314 */
51470298 3315 s->tried_publickey = 1;
3316
3317 {
222d54dc 3318 const char *error = NULL;
3319 int ret = loadrsakey(&ssh->cfg.keyfile, &s->key, s->password,
3320 &error);
51470298 3321 if (ret == 0) {
3322 c_write_str(ssh, "Couldn't load private key from ");
9fab77dc 3323 c_write_str(ssh, filename_to_str(&ssh->cfg.keyfile));
222d54dc 3324 c_write_str(ssh, " (");
3325 c_write_str(ssh, error);
3326 c_write_str(ssh, ").\r\n");
51470298 3327 continue; /* go and try password */
3328 }
3329 if (ret == -1) {
3330 c_write_str(ssh, "Wrong passphrase.\r\n");
3331 s->tried_publickey = 0;
3332 continue; /* try again */
3333 }
32874aea 3334 }
3335
3336 /*
3337 * Send a public key attempt.
3338 */
51470298 3339 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
3340 PKT_BIGNUM, s->key.modulus, PKT_END);
32874aea 3341
ff3187f6 3342 crWaitUntil(pktin);
3343 if (pktin->type == SSH1_SMSG_FAILURE) {
51470298 3344 c_write_str(ssh, "Server refused our public key.\r\n");
32874aea 3345 continue; /* go and try password */
3346 }
ff3187f6 3347 if (pktin->type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
6b5cf8b4 3348 bombout(("Bizarre response to offer of public key"));
7ffdbc1a 3349 crStop(0);
32874aea 3350 }
32874aea 3351
51470298 3352 {
3353 int i;
3354 unsigned char buffer[32];
3355 Bignum challenge, response;
3356
ff3187f6 3357 if ((challenge = ssh1_pkt_getmp(pktin)) == NULL) {
0016d70b 3358 bombout(("Server's RSA challenge was badly formatted"));
3359 crStop(0);
3360 }
51470298 3361 response = rsadecrypt(challenge, &s->key);
3362 freebn(s->key.private_exponent);/* burn the evidence */
32874aea 3363
51470298 3364 for (i = 0; i < 32; i++) {
3365 buffer[i] = bignum_byte(response, 31 - i);
3366 }
3367
3368 MD5Init(&md5c);
3369 MD5Update(&md5c, buffer, 32);
3370 MD5Update(&md5c, s->session_id, 16);
3371 MD5Final(buffer, &md5c);
32874aea 3372
51470298 3373 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
3374 PKT_DATA, buffer, 16, PKT_END);
3375
3376 freebn(challenge);
3377 freebn(response);
3378 }
32874aea 3379
ff3187f6 3380 crWaitUntil(pktin);
3381 if (pktin->type == SSH1_SMSG_FAILURE) {
32874aea 3382 if (flags & FLAG_VERBOSE)
51470298 3383 c_write_str(ssh, "Failed to authenticate with"
3384 " our public key.\r\n");
32874aea 3385 continue; /* go and try password */
ff3187f6 3386 } else if (pktin->type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 3387 bombout(("Bizarre response to RSA authentication response"));
7ffdbc1a 3388 crStop(0);
32874aea 3389 }
3390
3391 break; /* we're through! */
3392 } else {
51470298 3393 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
32874aea 3394 /*
3395 * Defence against traffic analysis: we send a
3396 * whole bunch of packets containing strings of
3397 * different lengths. One of these strings is the
3398 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3399 * The others are all random data in
3400 * SSH1_MSG_IGNORE packets. This way a passive
3401 * listener can't tell which is the password, and
3402 * hence can't deduce the password length.
3403 *
3404 * Anybody with a password length greater than 16
3405 * bytes is going to have enough entropy in their
3406 * password that a listener won't find it _that_
3407 * much help to know how long it is. So what we'll
3408 * do is:
3409 *
3410 * - if password length < 16, we send 15 packets
3411 * containing string lengths 1 through 15
3412 *
3413 * - otherwise, we let N be the nearest multiple
3414 * of 8 below the password length, and send 8
3415 * packets containing string lengths N through
3416 * N+7. This won't obscure the order of
3417 * magnitude of the password length, but it will
3418 * introduce a bit of extra uncertainty.
3419 *
3420 * A few servers (the old 1.2.18 through 1.2.22)
3421 * can't deal with SSH1_MSG_IGNORE. For these
3422 * servers, we need an alternative defence. We make
3423 * use of the fact that the password is interpreted
3424 * as a C string: so we can append a NUL, then some
3425 * random data.
bd358db1 3426 *
3427 * One server (a Cisco one) can deal with neither
3428 * SSH1_MSG_IGNORE _nor_ a padded password string.
3429 * For this server we are left with no defences
3430 * against password length sniffing.
32874aea 3431 */
51470298 3432 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE)) {
b17c8428 3433 /*
3434 * The server can deal with SSH1_MSG_IGNORE, so
3435 * we can use the primary defence.
3436 */
32874aea 3437 int bottom, top, pwlen, i;
3438 char *randomstr;
3439
51470298 3440 pwlen = strlen(s->password);
32874aea 3441 if (pwlen < 16) {
3442 bottom = 0; /* zero length passwords are OK! :-) */
3443 top = 15;
3444 } else {
3445 bottom = pwlen & ~7;
3446 top = bottom + 7;
3447 }
3448
3449 assert(pwlen >= bottom && pwlen <= top);
3450
3d88e64d 3451 randomstr = snewn(top + 1, char);
32874aea 3452
3453 for (i = bottom; i <= top; i++) {
9a10ecf4 3454 if (i == pwlen) {
51470298 3455 defer_packet(ssh, s->pwpkt_type,
9a10ecf4 3456 PKTT_PASSWORD, PKT_STR, s->password,
3457 PKTT_OTHER, PKT_END);
3458 } else {
32874aea 3459 for (j = 0; j < i; j++) {
3460 do {
3461 randomstr[j] = random_byte();
3462 } while (randomstr[j] == '\0');
3463 }
3464 randomstr[i] = '\0';
51470298 3465 defer_packet(ssh, SSH1_MSG_IGNORE,
32874aea 3466 PKT_STR, randomstr, PKT_END);
3467 }
3468 }
bd358db1 3469 logevent("Sending password with camouflage packets");
51470298 3470 ssh_pkt_defersend(ssh);
679539d7 3471 sfree(randomstr);
bd358db1 3472 }
51470298 3473 else if (!(ssh->remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
b17c8428 3474 /*
3475 * The server can't deal with SSH1_MSG_IGNORE
3476 * but can deal with padded passwords, so we
3477 * can use the secondary defence.
3478 */
bd358db1 3479 char string[64];
51470298 3480 char *ss;
bd358db1 3481 int len;
3482
51470298 3483 len = strlen(s->password);
bd358db1 3484 if (len < sizeof(string)) {
51470298 3485 ss = string;
3486 strcpy(string, s->password);
bd358db1 3487 len++; /* cover the zero byte */
3488 while (len < sizeof(string)) {
3489 string[len++] = (char) random_byte();
3490 }
3491 } else {
51470298 3492 ss = s->password;
bd358db1 3493 }
3494 logevent("Sending length-padded password");
9a10ecf4 3495 send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
3496 PKT_INT, len, PKT_DATA, ss, len,
3497 PKTT_OTHER, PKT_END);
bd358db1 3498 } else {
3499 /*
3500 * The server has _both_
3501 * BUG_CHOKES_ON_SSH1_IGNORE and
3502 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3503 * therefore nothing we can do.
3504 */
3505 int len;
51470298 3506 len = strlen(s->password);
bd358db1 3507 logevent("Sending unpadded password");
9a10ecf4 3508 send_packet(ssh, s->pwpkt_type,
3509 PKTT_PASSWORD, PKT_INT, len,
3510 PKT_DATA, s->password, len,
3511 PKTT_OTHER, PKT_END);
32874aea 3512 }
3513 } else {
9a10ecf4 3514 send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
3515 PKT_STR, s->password, PKTT_OTHER, PKT_END);
32874aea 3516 }
3517 }
c5e9c988 3518 logevent("Sent password");
51470298 3519 memset(s->password, 0, strlen(s->password));
ff3187f6 3520 crWaitUntil(pktin);
3521 if (pktin->type == SSH1_SMSG_FAILURE) {
32874aea 3522 if (flags & FLAG_VERBOSE)
51470298 3523 c_write_str(ssh, "Access denied\r\n");
c5e9c988 3524 logevent("Authentication refused");
ff3187f6 3525 } else if (pktin->type != SSH1_SMSG_SUCCESS) {
3526 bombout(("Strange packet received, type %d", pktin->type));
7ffdbc1a 3527 crStop(0);
374330e2 3528 }
3529 }
3530
c5e9c988 3531 logevent("Authentication successful");
3532
fb09bf1c 3533 crFinish(1);
3534}
3535
32874aea 3536void sshfwd_close(struct ssh_channel *c)
3537{
51470298 3538 Ssh ssh = c->ssh;
3539
36f94d1f 3540 if (ssh->state != SSH_STATE_SESSION) {
3541 assert(ssh->state == SSH_STATE_CLOSED);
3542 return;
3543 }
3544
80e48603 3545 if (c && !c->closes) {
4ed34d25 3546 /*
3547 * If the channel's remoteid is -1, we have sent
3548 * CHANNEL_OPEN for this channel, but it hasn't even been
3549 * acknowledged by the server. So we must set a close flag
3550 * on it now, and then when the server acks the channel
3551 * open, we can close it then.
3552 */
36cac739 3553 if (((int)c->remoteid) != -1) {
51470298 3554 if (ssh->version == 1) {
3555 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid,
4ed34d25 3556 PKT_END);
3557 } else {
ff3187f6 3558 struct Packet *pktout;
3559 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
3560 ssh2_pkt_adduint32(pktout, c->remoteid);
3561 ssh2_pkt_send(ssh, pktout);
4ed34d25 3562 }
32874aea 3563 }
0357890f 3564 c->closes = 1; /* sent MSG_CLOSE */
32874aea 3565 if (c->type == CHAN_X11) {
3566 c->u.x11.s = NULL;
d74d141c 3567 logevent("Forwarded X11 connection terminated");
4ed34d25 3568 } else if (c->type == CHAN_SOCKDATA ||
3569 c->type == CHAN_SOCKDATA_DORMANT) {
d74d141c 3570 c->u.pfd.s = NULL;
3571 logevent("Forwarded port closed");
32874aea 3572 }
3573 }
3574}
3575
5471d09a 3576int sshfwd_write(struct ssh_channel *c, char *buf, int len)
32874aea 3577{
51470298 3578 Ssh ssh = c->ssh;
3579
36f94d1f 3580 if (ssh->state != SSH_STATE_SESSION) {
3581 assert(ssh->state == SSH_STATE_CLOSED);
3582 return 0;
3583 }
3584
51470298 3585 if (ssh->version == 1) {
3586 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
32874aea 3587 PKT_INT, c->remoteid,
9a10ecf4 3588 PKTT_DATA,
3589 PKT_INT, len, PKT_DATA, buf, len,
3590 PKTT_OTHER, PKT_END);
5471d09a 3591 /*
3592 * In SSH1 we can return 0 here - implying that forwarded
3593 * connections are never individually throttled - because
3594 * the only circumstance that can cause throttling will be
3595 * the whole SSH connection backing up, in which case
3596 * _everything_ will be throttled as a whole.
3597 */
3598 return 0;
783415f8 3599 } else {
32874aea 3600 ssh2_add_channel_data(c, buf, len);
5471d09a 3601 return ssh2_try_send(c);
3602 }
3603}
3604
3605void sshfwd_unthrottle(struct ssh_channel *c, int bufsize)
3606{
51470298 3607 Ssh ssh = c->ssh;
3608
36f94d1f 3609 if (ssh->state != SSH_STATE_SESSION) {
3610 assert(ssh->state == SSH_STATE_CLOSED);
3611 return;
3612 }
3613
51470298 3614 if (ssh->version == 1) {
5471d09a 3615 if (c->v.v1.throttling && bufsize < SSH1_BUFFER_LIMIT) {
3616 c->v.v1.throttling = 0;
51470298 3617 ssh1_throttle(ssh, -1);
5471d09a 3618 }
3619 } else {
3620 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
783415f8 3621 }
9c964e85 3622}
3623
06fadff5 3624static void ssh_queueing_handler(Ssh ssh, struct Packet *pktin)
3625{
3626 struct queued_handler *qh = ssh->qhead;
3627
3628 assert(qh != NULL);
3629
3630 assert(pktin->type == qh->msg1 || pktin->type == qh->msg2);
3631
3632 if (qh->msg1 > 0) {
3633 assert(ssh->packet_dispatch[qh->msg1] == ssh_queueing_handler);
3634 ssh->packet_dispatch[qh->msg1] = NULL;
3635 }
3636 if (qh->msg2 > 0) {
3637 assert(ssh->packet_dispatch[qh->msg2] == ssh_queueing_handler);
3638 ssh->packet_dispatch[qh->msg2] = NULL;
3639 }
3640
3641 if (qh->next) {
3642 ssh->qhead = qh->next;
3643
3644 if (ssh->qhead->msg1 > 0) {
3645 assert(ssh->packet_dispatch[ssh->qhead->msg1] == NULL);
3646 ssh->packet_dispatch[ssh->qhead->msg1] = ssh_queueing_handler;
3647 }
3648 if (ssh->qhead->msg2 > 0) {
3649 assert(ssh->packet_dispatch[ssh->qhead->msg2] == NULL);
3650 ssh->packet_dispatch[ssh->qhead->msg2] = ssh_queueing_handler;
3651 }
3652 } else {
3653 ssh->qhead = ssh->qtail = NULL;
3654 ssh->packet_dispatch[pktin->type] = NULL;
3655 }
3656
3657 qh->handler(ssh, pktin, qh->ctx);
3658
3659 sfree(qh);
3660}
3661
3662static void ssh_queue_handler(Ssh ssh, int msg1, int msg2,
3663 chandler_fn_t handler, void *ctx)
3664{
3665 struct queued_handler *qh;
3666
3667 qh = snew(struct queued_handler);
3668 qh->msg1 = msg1;
3669 qh->msg2 = msg2;
3670 qh->handler = handler;
3671 qh->ctx = ctx;
3672 qh->next = NULL;
3673
3674 if (ssh->qtail == NULL) {
3675 ssh->qhead = qh;
3676
3677 if (qh->msg1 > 0) {
3678 assert(ssh->packet_dispatch[qh->msg1] == NULL);
3679 ssh->packet_dispatch[qh->msg1] = ssh_queueing_handler;
3680 }
3681 if (qh->msg2 > 0) {
3682 assert(ssh->packet_dispatch[qh->msg2] == NULL);
3683 ssh->packet_dispatch[qh->msg2] = ssh_queueing_handler;
3684 }
3685 } else {
3686 ssh->qtail->next = qh;
3687 }
3688 ssh->qtail = qh;
3689}
3690
3691static void ssh_rportfwd_succfail(Ssh ssh, struct Packet *pktin, void *ctx)
3692{
3693 struct ssh_rportfwd *rpf, *pf = (struct ssh_rportfwd *)ctx;
3694
3695 if (pktin->type == (ssh->version == 1 ? SSH1_SMSG_SUCCESS :
3696 SSH2_MSG_REQUEST_SUCCESS)) {
3697 logeventf(ssh, "Remote port forwarding from %s enabled",
3698 pf->sportdesc);
3699 } else {
3700 logeventf(ssh, "Remote port forwarding from %s refused",
3701 pf->sportdesc);
3702
3703 rpf = del234(ssh->rportfwds, pf);
3704 assert(rpf == pf);
fda2feb1 3705 free_rportfwd(pf);
06fadff5 3706 }
3707}
3708
3709static void ssh_setup_portfwd(Ssh ssh, const Config *cfg)
3710{
84328ddb 3711 const char *portfwd_strptr = cfg->portfwd;
3712 struct ssh_portfwd *epf;
3713 int i;
06fadff5 3714
fda2feb1 3715 if (!ssh->portfwds) {
3716 ssh->portfwds = newtree234(ssh_portcmp);
3717 } else {
3718 /*
3719 * Go through the existing port forwardings and tag them
84328ddb 3720 * with status==DESTROY. Any that we want to keep will be
3721 * re-enabled (status==KEEP) as we go through the
3722 * configuration and find out which bits are the same as
3723 * they were before.
fda2feb1 3724 */
3725 struct ssh_portfwd *epf;
3726 int i;
3727 for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
84328ddb 3728 epf->status = DESTROY;
fda2feb1 3729 }
3730
06fadff5 3731 while (*portfwd_strptr) {
84328ddb 3732 char address_family, type;
3733 int sport,dport,sserv,dserv;
3734 char sports[256], dports[256], saddr[256], host[256];
3735 int n;
3736
05581745 3737 address_family = 'A';
3738 type = 'L';
84328ddb 3739 if (*portfwd_strptr == 'A' ||
3740 *portfwd_strptr == '4' ||
3741 *portfwd_strptr == '6')
3742 address_family = *portfwd_strptr++;
3743 if (*portfwd_strptr == 'L' ||
3744 *portfwd_strptr == 'R' ||
3745 *portfwd_strptr == 'D')
3746 type = *portfwd_strptr++;
05581745 3747
06fadff5 3748 saddr[0] = '\0';
05581745 3749
06fadff5 3750 n = 0;
3751 while (*portfwd_strptr && *portfwd_strptr != '\t') {
3752 if (*portfwd_strptr == ':') {
3753 /*
3754 * We've seen a colon in the middle of the
3755 * source port number. This means that
3756 * everything we've seen until now is the
3757 * source _address_, so we'll move it into
3758 * saddr and start sports from the beginning
3759 * again.
3760 */
3761 portfwd_strptr++;
3762 sports[n] = '\0';
3763 if (ssh->version == 1 && type == 'R') {
3764 logeventf(ssh, "SSH1 cannot handle remote source address "
3765 "spec \"%s\"; ignoring", sports);
3766 } else
3767 strcpy(saddr, sports);
3768 n = 0;
3769 }
3770 if (n < 255) sports[n++] = *portfwd_strptr++;
3771 }
3772 sports[n] = 0;
3773 if (type != 'D') {
3774 if (*portfwd_strptr == '\t')
3775 portfwd_strptr++;
3776 n = 0;
3777 while (*portfwd_strptr && *portfwd_strptr != ':') {
3778 if (n < 255) host[n++] = *portfwd_strptr++;
3779 }
3780 host[n] = 0;
3781 if (*portfwd_strptr == ':')
3782 portfwd_strptr++;
3783 n = 0;
3784 while (*portfwd_strptr) {
3785 if (n < 255) dports[n++] = *portfwd_strptr++;
3786 }
3787 dports[n] = 0;
3788 portfwd_strptr++;
3789 dport = atoi(dports);
3790 dserv = 0;
3791 if (dport == 0) {
3792 dserv = 1;
3793 dport = net_service_lookup(dports);
3794 if (!dport) {
3795 logeventf(ssh, "Service lookup failed for destination"
3796 " port \"%s\"", dports);
3797 }
3798 }
3799 } else {
3800 while (*portfwd_strptr) portfwd_strptr++;
3801 dport = dserv = -1;
3802 portfwd_strptr++; /* eat the NUL and move to next one */
3803 }
3804 sport = atoi(sports);
3805 sserv = 0;
3806 if (sport == 0) {
3807 sserv = 1;
3808 sport = net_service_lookup(sports);
3809 if (!sport) {
3810 logeventf(ssh, "Service lookup failed for source"
3811 " port \"%s\"", sports);
3812 }
3813 }
3814 if (sport && dport) {
3815 /* Set up a description of the source port. */
fda2feb1 3816 struct ssh_portfwd *pfrec, *epfrec;
fda2feb1 3817
3818 pfrec = snew(struct ssh_portfwd);
3819 pfrec->type = type;
3820 pfrec->saddr = *saddr ? dupstr(saddr) : NULL;
3fe92132 3821 pfrec->sserv = sserv ? dupstr(sports) : NULL;
fda2feb1 3822 pfrec->sport = sport;
84328ddb 3823 pfrec->daddr = *host ? dupstr(host) : NULL;
3fe92132 3824 pfrec->dserv = dserv ? dupstr(dports) : NULL;
fda2feb1 3825 pfrec->dport = dport;
3826 pfrec->local = NULL;
3827 pfrec->remote = NULL;
05581745 3828 pfrec->addressfamily = (address_family == '4' ? ADDRTYPE_IPV4 :
3829 address_family == '6' ? ADDRTYPE_IPV6 :
3830 ADDRTYPE_UNSPEC);
fda2feb1 3831
3832 epfrec = add234(ssh->portfwds, pfrec);
3833 if (epfrec != pfrec) {
3834 /*
3835 * We already have a port forwarding with precisely
3836 * these parameters. Hence, no need to do anything;
84328ddb 3837 * simply tag the existing one as KEEP.
fda2feb1 3838 */
84328ddb 3839 epfrec->status = KEEP;
fda2feb1 3840 free_portfwd(pfrec);
84328ddb 3841 } else {
3842 pfrec->status = CREATE;
3843 }
3844 }
3845 }
3846
3847 /*
3848 * Now go through and destroy any port forwardings which were
3849 * not re-enabled.
3850 */
3851 for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
3852 if (epf->status == DESTROY) {
3853 char *message;
3854
3855 message = dupprintf("%s port forwarding from %s%s%d",
3856 epf->type == 'L' ? "local" :
3857 epf->type == 'R' ? "remote" : "dynamic",
3858 epf->saddr ? epf->saddr : "",
3859 epf->saddr ? ":" : "",
3860 epf->sport);
3861
3862 if (epf->type != 'D') {
3863 char *msg2 = dupprintf("%s to %s:%d", message,
3864 epf->daddr, epf->dport);
3865 sfree(message);
3866 message = msg2;
3867 }
3868
3869 logeventf(ssh, "Cancelling %s", message);
3870 sfree(message);
3871
3872 if (epf->remote) {
3873 struct ssh_rportfwd *rpf = epf->remote;
3874 struct Packet *pktout;
3875
3876 /*
3877 * Cancel the port forwarding at the server
3878 * end.
3879 */
3880 if (ssh->version == 1) {
3881 /*
3882 * We cannot cancel listening ports on the
3883 * server side in SSH1! There's no message
3884 * to support it. Instead, we simply remove
3885 * the rportfwd record from the local end
3886 * so that any connections the server tries
3887 * to make on it are rejected.
3888 */
3889 } else {
3890 pktout = ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST);
3891 ssh2_pkt_addstring(pktout, "cancel-tcpip-forward");
3892 ssh2_pkt_addbool(pktout, 0);/* _don't_ want reply */
3893 if (epf->saddr) {
3894 ssh2_pkt_addstring(pktout, epf->saddr);
3895 } else if (ssh->cfg.rport_acceptall) {
3896 ssh2_pkt_addstring(pktout, "0.0.0.0");
3897 } else {
3898 ssh2_pkt_addstring(pktout, "127.0.0.1");
3899 }
3900 ssh2_pkt_adduint32(pktout, epf->sport);
3901 ssh2_pkt_send(ssh, pktout);
3902 }
3903
3904 del234(ssh->rportfwds, rpf);
3905 free_rportfwd(rpf);
3906 } else if (epf->local) {
3907 pfd_terminate(epf->local);
3908 }
3909
3910 delpos234(ssh->portfwds, i);
3911 free_portfwd(epf);
3912 i--; /* so we don't skip one in the list */
3913 }
3914
3915 /*
3916 * And finally, set up any new port forwardings (status==CREATE).
3917 */
3918 for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
3919 if (epf->status == CREATE) {
3920 char *sportdesc, *dportdesc;
3fe92132 3921 sportdesc = dupprintf("%s%s%s%s%d%s",
84328ddb 3922 epf->saddr ? epf->saddr : "",
3923 epf->saddr ? ":" : "",
3fe92132 3924 epf->sserv ? epf->sserv : "",
3925 epf->sserv ? "(" : "",
3926 epf->sport,
3927 epf->sserv ? ")" : "");
84328ddb 3928 if (epf->type == 'D') {
3929 dportdesc = NULL;
3930 } else {
3fe92132 3931 dportdesc = dupprintf("%s:%s%s%d%s",
3932 epf->daddr,
3933 epf->dserv ? epf->dserv : "",
3934 epf->dserv ? "(" : "",
3935 epf->dport,
3936 epf->dserv ? ")" : "");
84328ddb 3937 }
05581745 3938
84328ddb 3939 if (epf->type == 'L') {
3940 const char *err = pfd_addforward(epf->daddr, epf->dport,
3941 epf->saddr, epf->sport,
3942 ssh, &ssh->cfg,
3943 &epf->local,
3944 epf->addressfamily);
3945
3946 logeventf(ssh, "Local %sport %s forwarding to %s%s%s",
3947 epf->addressfamily == ADDRTYPE_IPV4 ? "IPv4 " :
3948 epf->addressfamily == ADDRTYPE_IPV6 ? "IPv6 " : "",
3949 sportdesc, dportdesc,
3950 err ? " failed: " : "", err ? err : "");
3951 } else if (epf->type == 'D') {
06fadff5 3952 const char *err = pfd_addforward(NULL, -1,
84328ddb 3953 epf->saddr, epf->sport,
3954 ssh, &ssh->cfg,
3955 &epf->local,
3956 epf->addressfamily);
3957
3958 logeventf(ssh, "Local %sport %s SOCKS dynamic forwarding%s%s",
3959 epf->addressfamily == ADDRTYPE_IPV4 ? "IPv4 " :
3960 epf->addressfamily == ADDRTYPE_IPV6 ? "IPv6 " : "",
3961 sportdesc,
3962 err ? " failed: " : "", err ? err : "");
06fadff5 3963 } else {
3964 struct ssh_rportfwd *pf;
3965
3966 /*
3967 * Ensure the remote port forwardings tree exists.
3968 */
3969 if (!ssh->rportfwds) {
3970 if (ssh->version == 1)
3971 ssh->rportfwds = newtree234(ssh_rportcmp_ssh1);
3972 else
3973 ssh->rportfwds = newtree234(ssh_rportcmp_ssh2);
3974 }
3975
3976 pf = snew(struct ssh_rportfwd);
84328ddb 3977 strncpy(pf->dhost, epf->daddr, lenof(pf->dhost)-1);
3978 pf->dhost[lenof(pf->dhost)-1] = '\0';
3979 pf->dport = epf->dport;
3980 pf->sport = epf->sport;
06fadff5 3981 if (add234(ssh->rportfwds, pf) != pf) {
3982 logeventf(ssh, "Duplicate remote port forwarding to %s:%d",
84328ddb 3983 epf->daddr, epf->dport);
06fadff5 3984 sfree(pf);
3985 } else {
3986 logeventf(ssh, "Requesting remote port %s"
84328ddb 3987 " forward to %s", sportdesc, dportdesc);
06fadff5 3988
3989 pf->sportdesc = sportdesc;
3990 sportdesc = NULL;
84328ddb 3991 epf->remote = pf;
3992 pf->pfrec = epf;
06fadff5 3993
3994 if (ssh->version == 1) {
3995 send_packet(ssh, SSH1_CMSG_PORT_FORWARD_REQUEST,
84328ddb 3996 PKT_INT, epf->sport,
3997 PKT_STR, epf->daddr,
3998 PKT_INT, epf->dport,
06fadff5 3999 PKT_END);
4000 ssh_queue_handler(ssh, SSH1_SMSG_SUCCESS,
4001 SSH1_SMSG_FAILURE,
4002 ssh_rportfwd_succfail, pf);
4003 } else {
4004 struct Packet *pktout;
4005 pktout = ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST);
4006 ssh2_pkt_addstring(pktout, "tcpip-forward");
4007 ssh2_pkt_addbool(pktout, 1);/* want reply */
84328ddb 4008 if (epf->saddr) {
4009 ssh2_pkt_addstring(pktout, epf->saddr);
06fadff5 4010 } else if (ssh->cfg.rport_acceptall) {
4011 ssh2_pkt_addstring(pktout, "0.0.0.0");
4012 } else {
4013 ssh2_pkt_addstring(pktout, "127.0.0.1");
4014 }
84328ddb 4015 ssh2_pkt_adduint32(pktout, epf->sport);
06fadff5 4016 ssh2_pkt_send(ssh, pktout);
4017
4018 ssh_queue_handler(ssh, SSH2_MSG_REQUEST_SUCCESS,
4019 SSH2_MSG_REQUEST_FAILURE,
4020 ssh_rportfwd_succfail, pf);
4021 }
4022 }
4023 }
4024 sfree(sportdesc);
84328ddb 4025 sfree(dportdesc);
06fadff5 4026 }
06fadff5 4027}
4028
51df0ab5 4029static void ssh1_smsg_stdout_stderr_data(Ssh ssh, struct Packet *pktin)
4030{
4031 char *string;
4032 int stringlen, bufsize;
4033
4034 ssh_pkt_getstring(pktin, &string, &stringlen);
4035 if (string == NULL) {
4036 bombout(("Incoming terminal data packet was badly formed"));
4037 return;
4038 }
4039
4040 bufsize = from_backend(ssh->frontend, pktin->type == SSH1_SMSG_STDERR_DATA,
4041 string, stringlen);
4042 if (!ssh->v1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
4043 ssh->v1_stdout_throttling = 1;
4044 ssh1_throttle(ssh, +1);
4045 }
4046}
4047
4048static void ssh1_smsg_x11_open(Ssh ssh, struct Packet *pktin)
4049{
4050 /* Remote side is trying to open a channel to talk to our
4051 * X-Server. Give them back a local channel number. */
4052 struct ssh_channel *c;
4053 int remoteid = ssh_pkt_getuint32(pktin);
4054
4055 logevent("Received X11 connect request");
4056 /* Refuse if X11 forwarding is disabled. */
4057 if (!ssh->X11_fwd_enabled) {
4058 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4059 PKT_INT, remoteid, PKT_END);
4060 logevent("Rejected X11 connect request");
4061 } else {
4062 c = snew(struct ssh_channel);
4063 c->ssh = ssh;
4064
4065 if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
4066 ssh->x11auth, NULL, -1, &ssh->cfg) != NULL) {
4067 logevent("Opening X11 forward connection failed");
4068 sfree(c);
4069 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4070 PKT_INT, remoteid, PKT_END);
4071 } else {
4072 logevent
4073 ("Opening X11 forward connection succeeded");
4074 c->remoteid = remoteid;
4075 c->localid = alloc_channel_id(ssh);
4076 c->closes = 0;
4077 c->v.v1.throttling = 0;
4078 c->type = CHAN_X11; /* identify channel type */
4079 add234(ssh->channels, c);
4080 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
4081 PKT_INT, c->remoteid, PKT_INT,
4082 c->localid, PKT_END);
4083 logevent("Opened X11 forward channel");
4084 }
4085 }
4086}
4087
4088static void ssh1_smsg_agent_open(Ssh ssh, struct Packet *pktin)
4089{
4090 /* Remote side is trying to open a channel to talk to our
4091 * agent. Give them back a local channel number. */
4092 struct ssh_channel *c;
4093 int remoteid = ssh_pkt_getuint32(pktin);
4094
4095 /* Refuse if agent forwarding is disabled. */
4096 if (!ssh->agentfwd_enabled) {
4097 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4098 PKT_INT, remoteid, PKT_END);
4099 } else {
4100 c = snew(struct ssh_channel);
4101 c->ssh = ssh;
4102 c->remoteid = remoteid;
4103 c->localid = alloc_channel_id(ssh);
4104 c->closes = 0;
4105 c->v.v1.throttling = 0;
4106 c->type = CHAN_AGENT; /* identify channel type */
4107 c->u.a.lensofar = 0;
4108 add234(ssh->channels, c);
4109 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
4110 PKT_INT, c->remoteid, PKT_INT, c->localid,
4111 PKT_END);
4112 }
4113}
4114
4115static void ssh1_msg_port_open(Ssh ssh, struct Packet *pktin)
4116{
4117 /* Remote side is trying to open a channel to talk to a
4118 * forwarded port. Give them back a local channel number. */
4119 struct ssh_channel *c;
05581745 4120 struct ssh_rportfwd pf, *pfp;
51df0ab5 4121 int remoteid;
4122 int hostsize, port;
4123 char *host, buf[1024];
4124 const char *e;
4125 c = snew(struct ssh_channel);
4126 c->ssh = ssh;
4127
4128 remoteid = ssh_pkt_getuint32(pktin);
4129 ssh_pkt_getstring(pktin, &host, &hostsize);
4130 port = ssh_pkt_getuint32(pktin);
4131
4132 if (hostsize >= lenof(pf.dhost))
4133 hostsize = lenof(pf.dhost)-1;
4134 memcpy(pf.dhost, host, hostsize);
4135 pf.dhost[hostsize] = '\0';
4136 pf.dport = port;
05581745 4137 pfp = find234(ssh->rportfwds, &pf, NULL);
51df0ab5 4138
05581745 4139 if (pfp == NULL) {
51df0ab5 4140 sprintf(buf, "Rejected remote port open request for %s:%d",
4141 pf.dhost, port);
4142 logevent(buf);
4143 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4144 PKT_INT, remoteid, PKT_END);
4145 } else {
4146 sprintf(buf, "Received remote port open request for %s:%d",
4147 pf.dhost, port);
4148 logevent(buf);
4149 e = pfd_newconnect(&c->u.pfd.s, pf.dhost, port,
05581745 4150 c, &ssh->cfg, pfp->pfrec->addressfamily);
51df0ab5 4151 if (e != NULL) {
4152 char buf[256];
4153 sprintf(buf, "Port open failed: %s", e);
4154 logevent(buf);
4155 sfree(c);
4156 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4157 PKT_INT, remoteid, PKT_END);
4158 } else {
4159 c->remoteid = remoteid;
4160 c->localid = alloc_channel_id(ssh);
4161 c->closes = 0;
4162 c->v.v1.throttling = 0;
4163 c->type = CHAN_SOCKDATA; /* identify channel type */
4164 add234(ssh->channels, c);
4165 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
4166 PKT_INT, c->remoteid, PKT_INT,
4167 c->localid, PKT_END);
4168 logevent("Forwarded port opened successfully");
4169 }
4170 }
4171}
4172
4173static void ssh1_msg_channel_open_confirmation(Ssh ssh, struct Packet *pktin)
4174{
4175 unsigned int remoteid = ssh_pkt_getuint32(pktin);
4176 unsigned int localid = ssh_pkt_getuint32(pktin);
4177 struct ssh_channel *c;
4178
4179 c = find234(ssh->channels, &remoteid, ssh_channelfind);
4180 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
4181 c->remoteid = localid;
4182 c->type = CHAN_SOCKDATA;
4183 c->v.v1.throttling = 0;
4184 pfd_confirm(c->u.pfd.s);
4185 }
4186
4187 if (c && c->closes) {
4188 /*
4189 * We have a pending close on this channel,
4190 * which we decided on before the server acked
4191 * the channel open. So now we know the
4192 * remoteid, we can close it again.
4193 */
4194 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE,
4195 PKT_INT, c->remoteid, PKT_END);
4196 }
4197}
4198
4199static void ssh1_msg_channel_open_failure(Ssh ssh, struct Packet *pktin)
4200{
4201 unsigned int remoteid = ssh_pkt_getuint32(pktin);
4202 struct ssh_channel *c;
4203
4204 c = find234(ssh->channels, &remoteid, ssh_channelfind);
4205 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
4206 logevent("Forwarded connection refused by server");
4207 pfd_close(c->u.pfd.s);
4208 del234(ssh->channels, c);
4209 sfree(c);
4210 }
4211}
4212
4213static void ssh1_msg_channel_close(Ssh ssh, struct Packet *pktin)
4214{
4215 /* Remote side closes a channel. */
4216 unsigned i = ssh_pkt_getuint32(pktin);
4217 struct ssh_channel *c;
4218 c = find234(ssh->channels, &i, ssh_channelfind);
4219 if (c && ((int)c->remoteid) != -1) {
4220 int closetype;
4221 closetype =
4222 (pktin->type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
4223
4224 if ((c->closes == 0) && (c->type == CHAN_X11)) {
4225 logevent("Forwarded X11 connection terminated");
4226 assert(c->u.x11.s != NULL);
4227 x11_close(c->u.x11.s);
4228 c->u.x11.s = NULL;
4229 }
4230 if ((c->closes == 0) && (c->type == CHAN_SOCKDATA)) {
4231 logevent("Forwarded port closed");
4232 assert(c->u.pfd.s != NULL);
4233 pfd_close(c->u.pfd.s);
4234 c->u.pfd.s = NULL;
4235 }
4236
4237 c->closes |= (closetype << 2); /* seen this message */
4238 if (!(c->closes & closetype)) {
4239 send_packet(ssh, pktin->type, PKT_INT, c->remoteid,
4240 PKT_END);
4241 c->closes |= closetype; /* sent it too */
4242 }
4243
4244 if (c->closes == 15) {
4245 del234(ssh->channels, c);
4246 sfree(c);
4247 }
4248 } else {
4249 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
4250 pktin->type == SSH1_MSG_CHANNEL_CLOSE ? "" :
4251 "_CONFIRMATION", c ? "half-open" : "nonexistent",
4252 i));
4253 }
4254}
4255
4256static void ssh1_msg_channel_data(Ssh ssh, struct Packet *pktin)
4257{
4258 /* Data sent down one of our channels. */
4259 int i = ssh_pkt_getuint32(pktin);
4260 char *p;
aa63ab7e 4261 unsigned int len;
51df0ab5 4262 struct ssh_channel *c;
4263
4264 ssh_pkt_getstring(pktin, &p, &len);
4265
4266 c = find234(ssh->channels, &i, ssh_channelfind);
4267 if (c) {
4268 int bufsize = 0;
4269 switch (c->type) {
4270 case CHAN_X11:
4271 bufsize = x11_send(c->u.x11.s, p, len);
4272 break;
4273 case CHAN_SOCKDATA:
4274 bufsize = pfd_send(c->u.pfd.s, p, len);
4275 break;
4276 case CHAN_AGENT:
4277 /* Data for an agent message. Buffer it. */
4278 while (len > 0) {
4279 if (c->u.a.lensofar < 4) {
aa63ab7e 4280 unsigned int l = min(4 - c->u.a.lensofar, len);
51df0ab5 4281 memcpy(c->u.a.msglen + c->u.a.lensofar, p,
4282 l);
4283 p += l;
4284 len -= l;
4285 c->u.a.lensofar += l;
4286 }
4287 if (c->u.a.lensofar == 4) {
4288 c->u.a.totallen =
4289 4 + GET_32BIT(c->u.a.msglen);
4290 c->u.a.message = snewn(c->u.a.totallen,
4291 unsigned char);
4292 memcpy(c->u.a.message, c->u.a.msglen, 4);
4293 }
4294 if (c->u.a.lensofar >= 4 && len > 0) {
aa63ab7e 4295 unsigned int l =
51df0ab5 4296 min(c->u.a.totallen - c->u.a.lensofar,
4297 len);
4298 memcpy(c->u.a.message + c->u.a.lensofar, p,
4299 l);
4300 p += l;
4301 len -= l;
4302 c->u.a.lensofar += l;
4303 }
4304 if (c->u.a.lensofar == c->u.a.totallen) {
4305 void *reply;
4306 int replylen;
4307 if (agent_query(c->u.a.message,
4308 c->u.a.totallen,
4309 &reply, &replylen,
4310 ssh_agentf_callback, c))
4311 ssh_agentf_callback(c, reply, replylen);
4312 sfree(c->u.a.message);
4313 c->u.a.lensofar = 0;
4314 }
4315 }
4316 bufsize = 0; /* agent channels never back up */
4317 break;
4318 }
4319 if (!c->v.v1.throttling && bufsize > SSH1_BUFFER_LIMIT) {
4320 c->v.v1.throttling = 1;
4321 ssh1_throttle(ssh, +1);
4322 }
4323 }
4324}
4325
4326static void ssh1_smsg_exit_status(Ssh ssh, struct Packet *pktin)
4327{
4328 char buf[100];
4329 ssh->exitcode = ssh_pkt_getuint32(pktin);
4330 sprintf(buf, "Server sent command exit status %d",
4331 ssh->exitcode);
4332 logevent(buf);
4333 send_packet(ssh, SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
4334 /*
4335 * In case `helpful' firewalls or proxies tack
4336 * extra human-readable text on the end of the
4337 * session which we might mistake for another
4338 * encrypted packet, we close the session once
4339 * we've sent EXIT_CONFIRMATION.
4340 */
ac934965 4341 ssh->close_expected = TRUE;
51df0ab5 4342 ssh_closing((Plug)ssh, NULL, 0, 0);
4343}
4344
b09eaa88 4345static void do_ssh1_connection(Ssh ssh, unsigned char *in, int inlen,
4346 struct Packet *pktin)
32874aea 4347{
b09eaa88 4348 crBegin(ssh->do_ssh1_connection_crstate);
fb09bf1c 4349
51df0ab5 4350 ssh->packet_dispatch[SSH1_SMSG_STDOUT_DATA] =
4351 ssh->packet_dispatch[SSH1_SMSG_STDERR_DATA] =
4352 ssh1_smsg_stdout_stderr_data;
4353
4354 ssh->packet_dispatch[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION] =
4355 ssh1_msg_channel_open_confirmation;
4356 ssh->packet_dispatch[SSH1_MSG_CHANNEL_OPEN_FAILURE] =
4357 ssh1_msg_channel_open_failure;
4358 ssh->packet_dispatch[SSH1_MSG_CHANNEL_CLOSE] =
4359 ssh->packet_dispatch[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION] =
4360 ssh1_msg_channel_close;
4361 ssh->packet_dispatch[SSH1_MSG_CHANNEL_DATA] = ssh1_msg_channel_data;
4362 ssh->packet_dispatch[SSH1_SMSG_EXIT_STATUS] = ssh1_smsg_exit_status;
4363
86916870 4364 if (ssh->cfg.agentfwd && agent_exists()) {
32874aea 4365 logevent("Requesting agent forwarding");
51470298 4366 send_packet(ssh, SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
32874aea 4367 do {
4368 crReturnV;
ff3187f6 4369 } while (!pktin);
4370 if (pktin->type != SSH1_SMSG_SUCCESS
4371 && pktin->type != SSH1_SMSG_FAILURE) {
6b5cf8b4 4372 bombout(("Protocol confusion"));
7ffdbc1a 4373 crStopV;
ff3187f6 4374 } else if (pktin->type == SSH1_SMSG_FAILURE) {
32874aea 4375 logevent("Agent forwarding refused");
4376 } else {
4377 logevent("Agent forwarding enabled");
51470298 4378 ssh->agentfwd_enabled = TRUE;
51df0ab5 4379 ssh->packet_dispatch[SSH1_SMSG_AGENT_OPEN] = ssh1_smsg_agent_open;
db7d555c 4380 }
dacbd0e8 4381 }
4382
86916870 4383 if (ssh->cfg.x11_forward) {
32874aea 4384 char proto[20], data[64];
4385 logevent("Requesting X11 forwarding");
302121de 4386 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
86916870 4387 data, sizeof(data), ssh->cfg.x11_auth);
4388 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
51470298 4389 if (ssh->v1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) {
4390 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
32874aea 4391 PKT_STR, proto, PKT_STR, data,
86916870 4392 PKT_INT, x11_get_screen_number(ssh->cfg.x11_display),
421d6835 4393 PKT_END);
32874aea 4394 } else {
51470298 4395 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
32874aea 4396 PKT_STR, proto, PKT_STR, data, PKT_END);
4397 }
4398 do {
4399 crReturnV;
ff3187f6 4400 } while (!pktin);
4401 if (pktin->type != SSH1_SMSG_SUCCESS
4402 && pktin->type != SSH1_SMSG_FAILURE) {
6b5cf8b4 4403 bombout(("Protocol confusion"));
7ffdbc1a 4404 crStopV;
ff3187f6 4405 } else if (pktin->type == SSH1_SMSG_FAILURE) {
32874aea 4406 logevent("X11 forwarding refused");
4407 } else {
4408 logevent("X11 forwarding enabled");
51470298 4409 ssh->X11_fwd_enabled = TRUE;
51df0ab5 4410 ssh->packet_dispatch[SSH1_SMSG_X11_OPEN] = ssh1_smsg_x11_open;
9c964e85 4411 }
4412 }
4413
06fadff5 4414 ssh_setup_portfwd(ssh, &ssh->cfg);
4415 ssh->packet_dispatch[SSH1_MSG_PORT_OPEN] = ssh1_msg_port_open;
d74d141c 4416
86916870 4417 if (!ssh->cfg.nopty) {
a5dd8467 4418 /* Unpick the terminal-speed string. */
4419 /* XXX perhaps we should allow no speeds to be sent. */
db219738 4420 ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
4421 sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
a5dd8467 4422 /* Send the pty request. */
51470298 4423 send_packet(ssh, SSH1_CMSG_REQUEST_PTY,
86916870 4424 PKT_STR, ssh->cfg.termtype,
51470298 4425 PKT_INT, ssh->term_height,
4426 PKT_INT, ssh->term_width,
a5dd8467 4427 PKT_INT, 0, PKT_INT, 0, /* width,height in pixels */
db219738 4428 PKT_CHAR, 192, PKT_INT, ssh->ispeed, /* TTY_OP_ISPEED */
4429 PKT_CHAR, 193, PKT_INT, ssh->ospeed, /* TTY_OP_OSPEED */
a5dd8467 4430 PKT_CHAR, 0, PKT_END);
51470298 4431 ssh->state = SSH_STATE_INTERMED;
32874aea 4432 do {
4433 crReturnV;
ff3187f6 4434 } while (!pktin);
4435 if (pktin->type != SSH1_SMSG_SUCCESS
4436 && pktin->type != SSH1_SMSG_FAILURE) {
6b5cf8b4 4437 bombout(("Protocol confusion"));
7ffdbc1a 4438 crStopV;
ff3187f6 4439 } else if (pktin->type == SSH1_SMSG_FAILURE) {
51470298 4440 c_write_str(ssh, "Server refused to allocate pty\r\n");
4441 ssh->editing = ssh->echoing = 1;
32874aea 4442 }
a5dd8467 4443 logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
db219738 4444 ssh->ospeed, ssh->ispeed);
0965bee0 4445 } else {
51470298 4446 ssh->editing = ssh->echoing = 1;
374330e2 4447 }
4448
86916870 4449 if (ssh->cfg.compression) {
51470298 4450 send_packet(ssh, SSH1_CMSG_REQUEST_COMPRESSION, PKT_INT, 6, PKT_END);
32874aea 4451 do {
4452 crReturnV;
ff3187f6 4453 } while (!pktin);
4454 if (pktin->type != SSH1_SMSG_SUCCESS
4455 && pktin->type != SSH1_SMSG_FAILURE) {
6b5cf8b4 4456 bombout(("Protocol confusion"));
7ffdbc1a 4457 crStopV;
ff3187f6 4458 } else if (pktin->type == SSH1_SMSG_FAILURE) {
51470298 4459 c_write_str(ssh, "Server refused to compress\r\n");
32874aea 4460 }
4ba9b64b 4461 logevent("Started compression");
51470298 4462 ssh->v1_compressing = TRUE;
5366aed8 4463 ssh->cs_comp_ctx = zlib_compress_init();
4464 logevent("Initialised zlib (RFC1950) compression");
4465 ssh->sc_comp_ctx = zlib_decompress_init();
4466 logevent("Initialised zlib (RFC1950) decompression");
4ba9b64b 4467 }
4468
fd5e5847 4469 /*
4470 * Start the shell or command.
4471 *
4472 * Special case: if the first-choice command is an SSH2
4473 * subsystem (hence not usable here) and the second choice
4474 * exists, we fall straight back to that.
4475 */
4476 {
86916870 4477 char *cmd = ssh->cfg.remote_cmd_ptr;
fd5e5847 4478
86916870 4479 if (ssh->cfg.ssh_subsys && ssh->cfg.remote_cmd_ptr2) {
4480 cmd = ssh->cfg.remote_cmd_ptr2;
51470298 4481 ssh->fallback_cmd = TRUE;
fd5e5847 4482 }
4483 if (*cmd)
51470298 4484 send_packet(ssh, SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END);
fd5e5847 4485 else
51470298 4486 send_packet(ssh, SSH1_CMSG_EXEC_SHELL, PKT_END);
fd5e5847 4487 logevent("Started session");
4488 }
374330e2 4489
51470298 4490 ssh->state = SSH_STATE_SESSION;
4491 if (ssh->size_needed)
4492 ssh_size(ssh, ssh->term_width, ssh->term_height);
4493 if (ssh->eof_needed)
4494 ssh_special(ssh, TS_EOF);
374330e2 4495
b9d7bcad 4496 if (ssh->ldisc)
4497 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
51470298 4498 ssh->send_ok = 1;
4499 ssh->channels = newtree234(ssh_channelcmp);
374330e2 4500 while (1) {
d74d141c 4501
51df0ab5 4502 /*
4503 * By this point, most incoming packets are already being
4504 * handled by the dispatch table, and we need only pay
4505 * attention to the unusual ones.
4506 */
0357890f 4507
51df0ab5 4508 crReturnV;
4509 if (pktin) {
4510 if (pktin->type == SSH1_SMSG_SUCCESS) {
972a41c8 4511 /* may be from EXEC_SHELL on some servers */
ff3187f6 4512 } else if (pktin->type == SSH1_SMSG_FAILURE) {
972a41c8 4513 /* may be from EXEC_SHELL on some servers
374330e2 4514 * if no pty is available or in other odd cases. Ignore */
374330e2 4515 } else {
ff3187f6 4516 bombout(("Strange packet received: type %d", pktin->type));
7ffdbc1a 4517 crStopV;
374330e2 4518 }
4519 } else {
8df7a775 4520 while (inlen > 0) {
4521 int len = min(inlen, 512);
9a10ecf4 4522 send_packet(ssh, SSH1_CMSG_STDIN_DATA, PKTT_DATA,
4523 PKT_INT, len, PKT_DATA, in, len,
4524 PKTT_OTHER, PKT_END);
8df7a775 4525 in += len;
4526 inlen -= len;
4527 }
374330e2 4528 }
4529 }
4530
4531 crFinishV;
4532}
4533
4534/*
b09eaa88 4535 * Handle the top-level SSH2 protocol.
4536 */
4537static void ssh1_msg_debug(Ssh ssh, struct Packet *pktin)
4538{
4539 char *buf, *msg;
4540 int msglen;
4541
4542 ssh_pkt_getstring(pktin, &msg, &msglen);
4543 buf = dupprintf("Remote debug message: %.*s", msglen, msg);
4544 logevent(buf);
4545 sfree(buf);
4546}
4547
4548static void ssh1_msg_disconnect(Ssh ssh, struct Packet *pktin)
4549{
4550 /* log reason code in disconnect message */
4551 char *msg;
4552 int msglen;
4553
4554 ssh_pkt_getstring(pktin, &msg, &msglen);
4555 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen, msg));
4556}
4557
4558void ssh_msg_ignore(Ssh ssh, struct Packet *pktin)
4559{
4560 /* Do nothing, because we're ignoring it! Duhh. */
4561}
4562
4563static void ssh1_protocol_setup(Ssh ssh)
4564{
4565 int i;
4566
4567 /*
4568 * Most messages are handled by the coroutines.
4569 */
4570 for (i = 0; i < 256; i++)
4571 ssh->packet_dispatch[i] = NULL;
4572
4573 /*
4574 * These special message types we install handlers for.
4575 */
4576 ssh->packet_dispatch[SSH1_MSG_DISCONNECT] = ssh1_msg_disconnect;
4577 ssh->packet_dispatch[SSH1_MSG_IGNORE] = ssh_msg_ignore;
4578 ssh->packet_dispatch[SSH1_MSG_DEBUG] = ssh1_msg_debug;
4579}
4580
4581static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen,
4582 struct Packet *pktin)
4583{
4584 if (ssh->state == SSH_STATE_CLOSED)
4585 return;
4586
4587 if (pktin && ssh->packet_dispatch[pktin->type]) {
4588 ssh->packet_dispatch[pktin->type](ssh, pktin);
4589 return;
4590 }
4591
4592 if (!ssh->protocol_initial_phase_done) {
4593 if (do_ssh1_login(ssh, in, inlen, pktin))
4594 ssh->protocol_initial_phase_done = TRUE;
4595 else
4596 return;
4597 }
4598
4599 do_ssh1_connection(ssh, in, inlen, pktin);
4600}
4601
4602/*
e5574168 4603 * Utility routine for decoding comma-separated strings in KEXINIT.
4604 */
32874aea 4605static int in_commasep_string(char *needle, char *haystack, int haylen)
4606{
57356d63 4607 int needlen;
4608 if (!needle || !haystack) /* protect against null pointers */
4609 return 0;
4610 needlen = strlen(needle);
e5574168 4611 while (1) {
32874aea 4612 /*
4613 * Is it at the start of the string?
4614 */
4615 if (haylen >= needlen && /* haystack is long enough */
4616 !memcmp(needle, haystack, needlen) && /* initial match */
4617 (haylen == needlen || haystack[needlen] == ',')
4618 /* either , or EOS follows */
4619 )
4620 return 1;
4621 /*
4622 * If not, search for the next comma and resume after that.
4623 * If no comma found, terminate.
4624 */
4625 while (haylen > 0 && *haystack != ',')
4626 haylen--, haystack++;
4627 if (haylen == 0)
4628 return 0;
4629 haylen--, haystack++; /* skip over comma itself */
e5574168 4630 }
4631}
4632
4633/*
d39f364a 4634 * SSH2 key creation method.
4635 */
d8baa528 4636static void ssh2_mkkey(Ssh ssh, Bignum K, unsigned char *H,
4637 unsigned char *sessid, char chr,
4638 unsigned char *keyspace)
32874aea 4639{
d39f364a 4640 SHA_State s;
4641 /* First 20 bytes. */
4642 SHA_Init(&s);
51470298 4643 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
088bde77 4644 sha_mpint(&s, K);
d39f364a 4645 SHA_Bytes(&s, H, 20);
4646 SHA_Bytes(&s, &chr, 1);
5e0d7cb8 4647 SHA_Bytes(&s, sessid, 20);
d39f364a 4648 SHA_Final(&s, keyspace);
4649 /* Next 20 bytes. */
4650 SHA_Init(&s);
51470298 4651 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
088bde77 4652 sha_mpint(&s, K);
d39f364a 4653 SHA_Bytes(&s, H, 20);
4654 SHA_Bytes(&s, keyspace, 20);
32874aea 4655 SHA_Final(&s, keyspace + 20);
d39f364a 4656}
4657
4658/*
7cca0d81 4659 * Handle the SSH2 transport layer.
e5574168 4660 */
ff3187f6 4661static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen,
4662 struct Packet *pktin)
e5574168 4663{
51470298 4664 struct do_ssh2_transport_state {
4665 int nbits, pbits, warn;
4666 Bignum p, g, e, f, K;
4667 int kex_init_value, kex_reply_value;
4668 const struct ssh_mac **maclist;
4669 int nmacs;
4670 const struct ssh2_cipher *cscipher_tobe;
4671 const struct ssh2_cipher *sccipher_tobe;
4672 const struct ssh_mac *csmac_tobe;
4673 const struct ssh_mac *scmac_tobe;
4674 const struct ssh_compress *cscomp_tobe;
4675 const struct ssh_compress *sccomp_tobe;
4676 char *hostkeydata, *sigdata, *keystr, *fingerprint;
4677 int hostkeylen, siglen;
4678 void *hkey; /* actual host key */
4679 unsigned char exchange_hash[20];
83e7d008 4680 int n_preferred_kex;
4681 const struct ssh_kex *preferred_kex[KEX_MAX];
51470298 4682 int n_preferred_ciphers;
4683 const struct ssh2_ciphers *preferred_ciphers[CIPHER_MAX];
4684 const struct ssh_compress *preferred_comp;
e13bba36 4685 int got_session_id, activated_authconn;
ff3187f6 4686 struct Packet *pktout;
51470298 4687 };
4688 crState(do_ssh2_transport_state);
4689
4690 crBegin(ssh->do_ssh2_transport_crstate);
4691
4692 s->cscipher_tobe = s->sccipher_tobe = NULL;
4693 s->csmac_tobe = s->scmac_tobe = NULL;
4694 s->cscomp_tobe = s->sccomp_tobe = NULL;
4695
e13bba36 4696 s->got_session_id = s->activated_authconn = FALSE;
e5574168 4697
e13bba36 4698 /*
4699 * Be prepared to work around the buggy MAC problem.
4700 */
4701 if (ssh->remote_bugs & BUG_SSH2_HMAC)
4702 s->maclist = buggymacs, s->nmacs = lenof(buggymacs);
4703 else
4704 s->maclist = macs, s->nmacs = lenof(macs);
4705
4706 begin_key_exchange:
149d2abc 4707 ssh->pkt_ctx &= ~SSH2_PKTCTX_KEX_MASK;
51470298 4708 {
e13bba36 4709 int i, j, commalist_started;
4710
51470298 4711 /*
83e7d008 4712 * Set up the preferred key exchange. (NULL => warn below here)
4713 */
4714 s->n_preferred_kex = 0;
4715 for (i = 0; i < KEX_MAX; i++) {
4716 switch (ssh->cfg.ssh_kexlist[i]) {
4717 case KEX_DHGEX:
4718 s->preferred_kex[s->n_preferred_kex++] =
4719 &ssh_diffiehellman_gex;
4720 break;
4721 case KEX_DHGROUP14:
4722 s->preferred_kex[s->n_preferred_kex++] =
4723 &ssh_diffiehellman_group14;
4724 break;
4725 case KEX_DHGROUP1:
4726 s->preferred_kex[s->n_preferred_kex++] =
4727 &ssh_diffiehellman_group1;
4728 break;
4729 case CIPHER_WARN:
4730 /* Flag for later. Don't bother if it's the last in
4731 * the list. */
4732 if (i < KEX_MAX - 1) {
4733 s->preferred_kex[s->n_preferred_kex++] = NULL;
4734 }
4735 break;
4736 }
4737 }
83e7d008 4738
83e7d008 4739 /*
51470298 4740 * Set up the preferred ciphers. (NULL => warn below here)
4741 */
4742 s->n_preferred_ciphers = 0;
4743 for (i = 0; i < CIPHER_MAX; i++) {
86916870 4744 switch (ssh->cfg.ssh_cipherlist[i]) {
51470298 4745 case CIPHER_BLOWFISH:
4746 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_blowfish;
4747 break;
4748 case CIPHER_DES:
86916870 4749 if (ssh->cfg.ssh2_des_cbc) {
51470298 4750 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_des;
4751 }
4752 break;
4753 case CIPHER_3DES:
4754 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_3des;
4755 break;
4756 case CIPHER_AES:
4757 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_aes;
4758 break;
4759 case CIPHER_WARN:
4760 /* Flag for later. Don't bother if it's the last in
4761 * the list. */
4762 if (i < CIPHER_MAX - 1) {
4763 s->preferred_ciphers[s->n_preferred_ciphers++] = NULL;
4764 }
4765 break;
ca20bfcf 4766 }
ca20bfcf 4767 }
7591b9ff 4768
e13bba36 4769 /*
4770 * Set up preferred compression.
4771 */
4772 if (ssh->cfg.compression)
4773 s->preferred_comp = &ssh_zlib;
4774 else
4775 s->preferred_comp = &ssh_comp_none;
51470298 4776
4777 /*
590f6a5f 4778 * Enable queueing of outgoing auth- or connection-layer
4779 * packets while we are in the middle of a key exchange.
4780 */
4781 ssh->queueing = TRUE;
4782
4783 /*
9442dd57 4784 * Flag that KEX is in progress.
4785 */
4786 ssh->kex_in_progress = TRUE;
4787
4788 /*
51470298 4789 * Construct and send our key exchange packet.
4790 */
ff3187f6 4791 s->pktout = ssh2_pkt_init(SSH2_MSG_KEXINIT);
51470298 4792 for (i = 0; i < 16; i++)
ff3187f6 4793 ssh2_pkt_addbyte(s->pktout, (unsigned char) random_byte());
51470298 4794 /* List key exchange algorithms. */
ff3187f6 4795 ssh2_pkt_addstring_start(s->pktout);
83e7d008 4796 commalist_started = 0;
4797 for (i = 0; i < s->n_preferred_kex; i++) {
4798 const struct ssh_kex *k = s->preferred_kex[i];
4799 if (!k) continue; /* warning flag */
4800 if (commalist_started)
ff3187f6 4801 ssh2_pkt_addstring_str(s->pktout, ",");
83e7d008 4802 ssh2_pkt_addstring_str(s->pktout, s->preferred_kex[i]->name);
4803 commalist_started = 1;
32874aea 4804 }
51470298 4805 /* List server host key algorithms. */
ff3187f6 4806 ssh2_pkt_addstring_start(s->pktout);
51470298 4807 for (i = 0; i < lenof(hostkey_algs); i++) {
ff3187f6 4808 ssh2_pkt_addstring_str(s->pktout, hostkey_algs[i]->name);
51470298 4809 if (i < lenof(hostkey_algs) - 1)
ff3187f6 4810 ssh2_pkt_addstring_str(s->pktout, ",");
32874aea 4811 }
51470298 4812 /* List client->server encryption algorithms. */
ff3187f6 4813 ssh2_pkt_addstring_start(s->pktout);
83e7d008 4814 commalist_started = 0;
51470298 4815 for (i = 0; i < s->n_preferred_ciphers; i++) {
4816 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4817 if (!c) continue; /* warning flag */
4818 for (j = 0; j < c->nciphers; j++) {
83e7d008 4819 if (commalist_started)
ff3187f6 4820 ssh2_pkt_addstring_str(s->pktout, ",");
4821 ssh2_pkt_addstring_str(s->pktout, c->list[j]->name);
83e7d008 4822 commalist_started = 1;
51470298 4823 }
4824 }
4825 /* List server->client encryption algorithms. */
ff3187f6 4826 ssh2_pkt_addstring_start(s->pktout);
83e7d008 4827 commalist_started = 0;
51470298 4828 for (i = 0; i < s->n_preferred_ciphers; i++) {
4829 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4830 if (!c) continue; /* warning flag */
4831 for (j = 0; j < c->nciphers; j++) {
83e7d008 4832 if (commalist_started)
ff3187f6 4833 ssh2_pkt_addstring_str(s->pktout, ",");
4834 ssh2_pkt_addstring_str(s->pktout, c->list[j]->name);
83e7d008 4835 commalist_started = 1;
51470298 4836 }
4837 }
4838 /* List client->server MAC algorithms. */
ff3187f6 4839 ssh2_pkt_addstring_start(s->pktout);
51470298 4840 for (i = 0; i < s->nmacs; i++) {
ff3187f6 4841 ssh2_pkt_addstring_str(s->pktout, s->maclist[i]->name);
51470298 4842 if (i < s->nmacs - 1)
ff3187f6 4843 ssh2_pkt_addstring_str(s->pktout, ",");
51470298 4844 }
4845 /* List server->client MAC algorithms. */
ff3187f6 4846 ssh2_pkt_addstring_start(s->pktout);
51470298 4847 for (i = 0; i < s->nmacs; i++) {
ff3187f6 4848 ssh2_pkt_addstring_str(s->pktout, s->maclist[i]->name);
51470298 4849 if (i < s->nmacs - 1)
ff3187f6 4850 ssh2_pkt_addstring_str(s->pktout, ",");
51470298 4851 }
4852 /* List client->server compression algorithms. */
ff3187f6 4853 ssh2_pkt_addstring_start(s->pktout);
f6e0abe2 4854 assert(lenof(compressions) > 1);
ff3187f6 4855 ssh2_pkt_addstring_str(s->pktout, s->preferred_comp->name);
f6e0abe2 4856 for (i = 0; i < lenof(compressions); i++) {
4857 const struct ssh_compress *c = compressions[i];
4858 if (c != s->preferred_comp) {
ff3187f6 4859 ssh2_pkt_addstring_str(s->pktout, ",");
4860 ssh2_pkt_addstring_str(s->pktout, c->name);
f6e0abe2 4861 }
51470298 4862 }
4863 /* List server->client compression algorithms. */
ff3187f6 4864 ssh2_pkt_addstring_start(s->pktout);
f6e0abe2 4865 assert(lenof(compressions) > 1);
ff3187f6 4866 ssh2_pkt_addstring_str(s->pktout, s->preferred_comp->name);
f6e0abe2 4867 for (i = 0; i < lenof(compressions); i++) {
4868 const struct ssh_compress *c = compressions[i];
4869 if (c != s->preferred_comp) {
ff3187f6 4870 ssh2_pkt_addstring_str(s->pktout, ",");
4871 ssh2_pkt_addstring_str(s->pktout, c->name);
f6e0abe2 4872 }
51470298 4873 }
4874 /* List client->server languages. Empty list. */
ff3187f6 4875 ssh2_pkt_addstring_start(s->pktout);
51470298 4876 /* List server->client languages. Empty list. */
ff3187f6 4877 ssh2_pkt_addstring_start(s->pktout);
51470298 4878 /* First KEX packet does _not_ follow, because we're not that brave. */
ff3187f6 4879 ssh2_pkt_addbool(s->pktout, FALSE);
51470298 4880 /* Reserved. */
ff3187f6 4881 ssh2_pkt_adduint32(s->pktout, 0);
e5574168 4882 }
0db56f73 4883
51470298 4884 ssh->exhash = ssh->exhashbase;
ff3187f6 4885 sha_string(&ssh->exhash, s->pktout->data + 5, s->pktout->length - 5);
0db56f73 4886
590f6a5f 4887 ssh2_pkt_send_noqueue(ssh, s->pktout);
e5574168 4888
ff3187f6 4889 if (!pktin)
4890 crWaitUntil(pktin);
4891 if (pktin->length > 5)
4892 sha_string(&ssh->exhash, pktin->data + 5, pktin->length - 5);
e5574168 4893
4894 /*
4895 * Now examine the other side's KEXINIT to see what we're up
4896 * to.
4897 */
51470298 4898 {
4899 char *str;
4900 int i, j, len;
4901
ff3187f6 4902 if (pktin->type != SSH2_MSG_KEXINIT) {
6b5cf8b4 4903 bombout(("expected key exchange packet from server"));
7ffdbc1a 4904 crStop(0);
32874aea 4905 }
51470298 4906 ssh->kex = NULL;
4907 ssh->hostkey = NULL;
4908 s->cscipher_tobe = NULL;
4909 s->sccipher_tobe = NULL;
4910 s->csmac_tobe = NULL;
4911 s->scmac_tobe = NULL;
4912 s->cscomp_tobe = NULL;
4913 s->sccomp_tobe = NULL;
ff3187f6 4914 pktin->savedpos += 16; /* skip garbage cookie */
4915 ssh_pkt_getstring(pktin, &str, &len); /* key exchange algorithms */
83e7d008 4916 s->warn = 0;
4917 for (i = 0; i < s->n_preferred_kex; i++) {
4918 const struct ssh_kex *k = s->preferred_kex[i];
4919 if (!k) {
4920 s->warn = 1;
4921 } else if (in_commasep_string(k->name, str, len)) {
4922 ssh->kex = k;
4923 }
4924 if (ssh->kex) {
bb348ab1 4925 if (s->warn) {
4926 sk_set_frozen(ssh->s, 1);
83e7d008 4927 askalg(ssh->frontend, "key-exchange algorithm",
4928 ssh->kex->name);
bb348ab1 4929 sk_set_frozen(ssh->s, 0);
4930 }
51470298 4931 break;
4932 }
32874aea 4933 }
83e7d008 4934 if (!ssh->kex) {
4935 bombout(("Couldn't agree a key exchange algorithm (available: %s)",
4936 str ? str : "(null)"));
4937 crStop(0);
4938 }
ff3187f6 4939 ssh_pkt_getstring(pktin, &str, &len); /* host key algorithms */
51470298 4940 for (i = 0; i < lenof(hostkey_algs); i++) {
4941 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
4942 ssh->hostkey = hostkey_algs[i];
4943 break;
4944 }
4945 }
ff3187f6 4946 ssh_pkt_getstring(pktin, &str, &len); /* client->server cipher */
51470298 4947 s->warn = 0;
4948 for (i = 0; i < s->n_preferred_ciphers; i++) {
4949 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4950 if (!c) {
4951 s->warn = 1;
4952 } else {
4953 for (j = 0; j < c->nciphers; j++) {
4954 if (in_commasep_string(c->list[j]->name, str, len)) {
4955 s->cscipher_tobe = c->list[j];
4956 break;
4957 }
ca20bfcf 4958 }
32874aea 4959 }
51470298 4960 if (s->cscipher_tobe) {
bb348ab1 4961 if (s->warn) {
4962 sk_set_frozen(ssh->s, 1);
83e7d008 4963 askalg(ssh->frontend, "client-to-server cipher",
4964 s->cscipher_tobe->name);
bb348ab1 4965 sk_set_frozen(ssh->s, 0);
4966 }
51470298 4967 break;
4968 }
32874aea 4969 }
51470298 4970 if (!s->cscipher_tobe) {
6b5cf8b4 4971 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
57356d63 4972 str ? str : "(null)"));
7ffdbc1a 4973 crStop(0);
ca20bfcf 4974 }
0ef8f407 4975
ff3187f6 4976 ssh_pkt_getstring(pktin, &str, &len); /* server->client cipher */
51470298 4977 s->warn = 0;
4978 for (i = 0; i < s->n_preferred_ciphers; i++) {
4979 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4980 if (!c) {
4981 s->warn = 1;
4982 } else {
4983 for (j = 0; j < c->nciphers; j++) {
4984 if (in_commasep_string(c->list[j]->name, str, len)) {
4985 s->sccipher_tobe = c->list[j];
4986 break;
4987 }
ca20bfcf 4988 }
32874aea 4989 }
51470298 4990 if (s->sccipher_tobe) {
bb348ab1 4991 if (s->warn) {
4992 sk_set_frozen(ssh->s, 1);
83e7d008 4993 askalg(ssh->frontend, "server-to-client cipher",
4994 s->sccipher_tobe->name);
bb348ab1 4995 sk_set_frozen(ssh->s, 0);
4996 }
51470298 4997 break;
4998 }
32874aea 4999 }
51470298 5000 if (!s->sccipher_tobe) {
6b5cf8b4 5001 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
57356d63 5002 str ? str : "(null)"));
7ffdbc1a 5003 crStop(0);
ca20bfcf 5004 }
0ef8f407 5005
ff3187f6 5006 ssh_pkt_getstring(pktin, &str, &len); /* client->server mac */
51470298 5007 for (i = 0; i < s->nmacs; i++) {
5008 if (in_commasep_string(s->maclist[i]->name, str, len)) {
5009 s->csmac_tobe = s->maclist[i];
5010 break;
5011 }
32874aea 5012 }
ff3187f6 5013 ssh_pkt_getstring(pktin, &str, &len); /* server->client mac */
51470298 5014 for (i = 0; i < s->nmacs; i++) {
5015 if (in_commasep_string(s->maclist[i]->name, str, len)) {
5016 s->scmac_tobe = s->maclist[i];
5017 break;
5018 }
32874aea 5019 }
ff3187f6 5020 ssh_pkt_getstring(pktin, &str, &len); /* client->server compression */
51470298 5021 for (i = 0; i < lenof(compressions) + 1; i++) {
5022 const struct ssh_compress *c =
5023 i == 0 ? s->preferred_comp : compressions[i - 1];
5024 if (in_commasep_string(c->name, str, len)) {
5025 s->cscomp_tobe = c;
5026 break;
5027 }
32874aea 5028 }
ff3187f6 5029 ssh_pkt_getstring(pktin, &str, &len); /* server->client compression */
51470298 5030 for (i = 0; i < lenof(compressions) + 1; i++) {
5031 const struct ssh_compress *c =
5032 i == 0 ? s->preferred_comp : compressions[i - 1];
5033 if (in_commasep_string(c->name, str, len)) {
5034 s->sccomp_tobe = c;
5035 break;
5036 }
32874aea 5037 }
e5574168 5038 }
e5574168 5039
5040 /*
7bd5a860 5041 * Work out the number of bits of key we will need from the key
5042 * exchange. We start with the maximum key length of either
5043 * cipher...
5044 */
5045 {
32874aea 5046 int csbits, scbits;
7bd5a860 5047
51470298 5048 csbits = s->cscipher_tobe->keylen;
5049 scbits = s->sccipher_tobe->keylen;
5050 s->nbits = (csbits > scbits ? csbits : scbits);
7bd5a860 5051 }
5052 /* The keys only have 160-bit entropy, since they're based on
5053 * a SHA-1 hash. So cap the key size at 160 bits. */
51470298 5054 if (s->nbits > 160)
5055 s->nbits = 160;
7bd5a860 5056
5057 /*
a92dd380 5058 * If we're doing Diffie-Hellman group exchange, start by
5059 * requesting a group.
e5574168 5060 */
d1aaf71d 5061 if (!ssh->kex->pdata) {
32874aea 5062 logevent("Doing Diffie-Hellman group exchange");
51470298 5063 ssh->pkt_ctx |= SSH2_PKTCTX_DHGEX;
32874aea 5064 /*
5065 * Work out how big a DH group we will need to allow that
5066 * much data.
7bd5a860 5067 */
51470298 5068 s->pbits = 512 << ((s->nbits - 1) / 64);
ff3187f6 5069 s->pktout = ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST);
5070 ssh2_pkt_adduint32(s->pktout, s->pbits);
590f6a5f 5071 ssh2_pkt_send_noqueue(ssh, s->pktout);
32874aea 5072
ff3187f6 5073 crWaitUntil(pktin);
5074 if (pktin->type != SSH2_MSG_KEX_DH_GEX_GROUP) {
6b5cf8b4 5075 bombout(("expected key exchange group packet from server"));
7ffdbc1a 5076 crStop(0);
32874aea 5077 }
ff3187f6 5078 s->p = ssh2_pkt_getmp(pktin);
5079 s->g = ssh2_pkt_getmp(pktin);
5080 if (!s->p || !s->g) {
5081 bombout(("unable to read mp-ints from incoming group packet"));
5082 crStop(0);
5083 }
d1aaf71d 5084 ssh->kex_ctx = dh_setup_gex(s->p, s->g);
51470298 5085 s->kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
5086 s->kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY;
a92dd380 5087 } else {
d1aaf71d 5088 ssh->pkt_ctx |= SSH2_PKTCTX_DHGROUP;
5089 ssh->kex_ctx = dh_setup_group(ssh->kex);
51470298 5090 s->kex_init_value = SSH2_MSG_KEXDH_INIT;
5091 s->kex_reply_value = SSH2_MSG_KEXDH_REPLY;
d1aaf71d 5092 logeventf(ssh, "Using Diffie-Hellman with standard group \"%s\"",
5093 ssh->kex->groupname);
8d5de777 5094 }
e5574168 5095
a92dd380 5096 logevent("Doing Diffie-Hellman key exchange");
e5574168 5097 /*
a92dd380 5098 * Now generate and send e for Diffie-Hellman.
e5574168 5099 */
27cd7fc2 5100 s->e = dh_create_e(ssh->kex_ctx, s->nbits * 2);
ff3187f6 5101 s->pktout = ssh2_pkt_init(s->kex_init_value);
5102 ssh2_pkt_addmp(s->pktout, s->e);
590f6a5f 5103 ssh2_pkt_send_noqueue(ssh, s->pktout);
e5574168 5104
ff3187f6 5105 crWaitUntil(pktin);
5106 if (pktin->type != s->kex_reply_value) {
6b5cf8b4 5107 bombout(("expected key exchange reply packet from server"));
7ffdbc1a 5108 crStop(0);
7cca0d81 5109 }
ff3187f6 5110 ssh_pkt_getstring(pktin, &s->hostkeydata, &s->hostkeylen);
5111 s->f = ssh2_pkt_getmp(pktin);
5112 if (!s->f) {
5113 bombout(("unable to parse key exchange reply packet"));
5114 crStop(0);
5115 }
5116 ssh_pkt_getstring(pktin, &s->sigdata, &s->siglen);
e5574168 5117
27cd7fc2 5118 s->K = dh_find_K(ssh->kex_ctx, s->f);
e5574168 5119
51470298 5120 sha_string(&ssh->exhash, s->hostkeydata, s->hostkeylen);
5121 if (ssh->kex == &ssh_diffiehellman_gex) {
5122 sha_uint32(&ssh->exhash, s->pbits);
5123 sha_mpint(&ssh->exhash, s->p);
5124 sha_mpint(&ssh->exhash, s->g);
a92dd380 5125 }
51470298 5126 sha_mpint(&ssh->exhash, s->e);
5127 sha_mpint(&ssh->exhash, s->f);
5128 sha_mpint(&ssh->exhash, s->K);
5129 SHA_Final(&ssh->exhash, s->exchange_hash);
e5574168 5130
27cd7fc2 5131 dh_cleanup(ssh->kex_ctx);
fabd1805 5132 ssh->kex_ctx = NULL;
3709bfe9 5133
7cca0d81 5134#if 0
765c4200 5135 debug(("Exchange hash is:\n"));
51470298 5136 dmemdump(s->exchange_hash, 20);
7cca0d81 5137#endif
5138
51470298 5139 s->hkey = ssh->hostkey->newkey(s->hostkeydata, s->hostkeylen);
5140 if (!s->hkey ||
5141 !ssh->hostkey->verifysig(s->hkey, s->sigdata, s->siglen,
d8baa528 5142 (char *)s->exchange_hash, 20)) {
6b5cf8b4 5143 bombout(("Server's host key did not match the signature supplied"));
7ffdbc1a 5144 crStop(0);
8d5de777 5145 }
e5574168 5146
5147 /*
7cca0d81 5148 * Authenticate remote host: verify host key. (We've already
5149 * checked the signature of the exchange hash.)
e5574168 5150 */
51470298 5151 s->keystr = ssh->hostkey->fmtkey(s->hkey);
5152 s->fingerprint = ssh->hostkey->fingerprint(s->hkey);
bb348ab1 5153 sk_set_frozen(ssh->s, 1);
a8327734 5154 verify_ssh_host_key(ssh->frontend,
5155 ssh->savedhost, ssh->savedport, ssh->hostkey->keytype,
51470298 5156 s->keystr, s->fingerprint);
bb348ab1 5157 sk_set_frozen(ssh->s, 0);
e13bba36 5158 if (!s->got_session_id) { /* don't bother logging this in rekeys */
5e0d7cb8 5159 logevent("Host key fingerprint is:");
51470298 5160 logevent(s->fingerprint);
5e0d7cb8 5161 }
51470298 5162 sfree(s->fingerprint);
5163 sfree(s->keystr);
5164 ssh->hostkey->freekey(s->hkey);
d39f364a 5165
5166 /*
9442dd57 5167 * The exchange hash from the very first key exchange is also
5168 * the session id, used in session key construction and
5169 * authentication.
5170 */
e13bba36 5171 if (!s->got_session_id) {
9442dd57 5172 memcpy(ssh->v2_session_id, s->exchange_hash,
5173 sizeof(s->exchange_hash));
e13bba36 5174 s->got_session_id = TRUE;
5175 }
9442dd57 5176
5177 /*
7cca0d81 5178 * Send SSH2_MSG_NEWKEYS.
d39f364a 5179 */
ff3187f6 5180 s->pktout = ssh2_pkt_init(SSH2_MSG_NEWKEYS);
590f6a5f 5181 ssh2_pkt_send_noqueue(ssh, s->pktout);
9442dd57 5182 ssh->outgoing_data_size = 0; /* start counting from here */
5183
5184 /*
5185 * We've sent client NEWKEYS, so create and initialise
c64fe7d4 5186 * client-to-server session keys.
9442dd57 5187 */
5188 if (ssh->cs_cipher_ctx)
5189 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
5190 ssh->cscipher = s->cscipher_tobe;
5191 ssh->cs_cipher_ctx = ssh->cscipher->make_context();
5192
5193 if (ssh->cs_mac_ctx)
5194 ssh->csmac->free_context(ssh->cs_mac_ctx);
5195 ssh->csmac = s->csmac_tobe;
5196 ssh->cs_mac_ctx = ssh->csmac->make_context();
5197
5198 if (ssh->cs_comp_ctx)
5199 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
5200 ssh->cscomp = s->cscomp_tobe;
5201 ssh->cs_comp_ctx = ssh->cscomp->compress_init();
5202
5203 /*
5204 * Set IVs on client-to-server keys. Here we use the exchange
5205 * hash from the _first_ key exchange.
5206 */
5207 {
5208 unsigned char keyspace[40];
5209 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'C',keyspace);
5210 ssh->cscipher->setkey(ssh->cs_cipher_ctx, keyspace);
5211 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'A',keyspace);
5212 ssh->cscipher->setiv(ssh->cs_cipher_ctx, keyspace);
5213 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'E',keyspace);
5214 ssh->csmac->setkey(ssh->cs_mac_ctx, keyspace);
5215 }
5216
5217 logeventf(ssh, "Initialised %.200s client->server encryption",
5218 ssh->cscipher->text_name);
5219 logeventf(ssh, "Initialised %.200s client->server MAC algorithm",
5220 ssh->csmac->text_name);
5221 if (ssh->cscomp->text_name)
5222 logeventf(ssh, "Initialised %s compression",
5223 ssh->cscomp->text_name);
590f6a5f 5224
5225 /*
5226 * Now our end of the key exchange is complete, we can send all
5227 * our queued higher-layer packets.
5228 */
5229 ssh->queueing = FALSE;
5230 ssh2_pkt_queuesend(ssh);
d39f364a 5231
5232 /*
8406eaf9 5233 * Expect SSH2_MSG_NEWKEYS from server.
5234 */
ff3187f6 5235 crWaitUntil(pktin);
5236 if (pktin->type != SSH2_MSG_NEWKEYS) {
6b5cf8b4 5237 bombout(("expected new-keys packet from server"));
7ffdbc1a 5238 crStop(0);
8406eaf9 5239 }
9442dd57 5240 ssh->incoming_data_size = 0; /* start counting from here */
8406eaf9 5241
5242 /*
9442dd57 5243 * We've seen server NEWKEYS, so create and initialise
5244 * server-to-client session keys.
d39f364a 5245 */
371e569c 5246 if (ssh->sc_cipher_ctx)
5247 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
51470298 5248 ssh->sccipher = s->sccipher_tobe;
371e569c 5249 ssh->sc_cipher_ctx = ssh->sccipher->make_context();
e0e1a00d 5250
e0e1a00d 5251 if (ssh->sc_mac_ctx)
5252 ssh->scmac->free_context(ssh->sc_mac_ctx);
51470298 5253 ssh->scmac = s->scmac_tobe;
e0e1a00d 5254 ssh->sc_mac_ctx = ssh->scmac->make_context();
5255
5366aed8 5256 if (ssh->sc_comp_ctx)
5257 ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
51470298 5258 ssh->sccomp = s->sccomp_tobe;
5366aed8 5259 ssh->sc_comp_ctx = ssh->sccomp->decompress_init();
5260
d39f364a 5261 /*
9442dd57 5262 * Set IVs on server-to-client keys. Here we use the exchange
5263 * hash from the _first_ key exchange.
d39f364a 5264 */
51470298 5265 {
5266 unsigned char keyspace[40];
51470298 5267 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'D',keyspace);
371e569c 5268 ssh->sccipher->setkey(ssh->sc_cipher_ctx, keyspace);
51470298 5269 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'B',keyspace);
371e569c 5270 ssh->sccipher->setiv(ssh->sc_cipher_ctx, keyspace);
51470298 5271 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'F',keyspace);
e0e1a00d 5272 ssh->scmac->setkey(ssh->sc_mac_ctx, keyspace);
51470298 5273 }
57356d63 5274 logeventf(ssh, "Initialised %.200s server->client encryption",
5275 ssh->sccipher->text_name);
6c135243 5276 logeventf(ssh, "Initialised %.200s server->client MAC algorithm",
5277 ssh->scmac->text_name);
57356d63 5278 if (ssh->sccomp->text_name)
5279 logeventf(ssh, "Initialised %s decompression",
5280 ssh->sccomp->text_name);
9442dd57 5281
5282 /*
5283 * Free key exchange data.
5284 */
679539d7 5285 freebn(s->f);
679539d7 5286 freebn(s->K);
b3949e7e 5287 if (ssh->kex == &ssh_diffiehellman_gex) {
5288 freebn(s->g);
5289 freebn(s->p);
5290 }
d39f364a 5291
033b4cef 5292 /*
e13bba36 5293 * Key exchange is over. Loop straight back round if we have a
5294 * deferred rekey reason.
5295 */
5296 if (ssh->deferred_rekey_reason) {
5297 logevent(ssh->deferred_rekey_reason);
5298 pktin = NULL;
5299 ssh->deferred_rekey_reason = NULL;
5300 goto begin_key_exchange;
5301 }
5302
5303 /*
5304 * Otherwise, schedule a timer for our next rekey.
9442dd57 5305 */
5306 ssh->kex_in_progress = FALSE;
e6c1536e 5307 ssh->last_rekey = GETTICKCOUNT();
d57f70af 5308 if (ssh->cfg.ssh_rekey_time != 0)
5309 ssh->next_rekey = schedule_timer(ssh->cfg.ssh_rekey_time*60*TICKSPERSEC,
5310 ssh2_timer, ssh);
e13bba36 5311
9442dd57 5312 /*
0db56f73 5313 * If this is the first key exchange phase, we must pass the
5314 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
5315 * wants to see it but because it will need time to initialise
5316 * itself before it sees an actual packet. In subsequent key
5317 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
5318 * it would only confuse the layer above.
5319 */
e13bba36 5320 if (s->activated_authconn) {
b09eaa88 5321 crReturn(1);
0db56f73 5322 }
e13bba36 5323 s->activated_authconn = TRUE;
0db56f73 5324
5325 /*
7cca0d81 5326 * Now we're encrypting. Begin returning 1 to the protocol main
5327 * function so that other things can run on top of the
5328 * transport. If we ever see a KEXINIT, we must go back to the
5329 * start.
9442dd57 5330 *
5331 * We _also_ go back to the start if we see pktin==NULL and
5332 * inlen==-1, because this is a special signal meaning
5333 * `initiate client-driven rekey', and `in' contains a message
5334 * giving the reason for the rekey.
033b4cef 5335 */
9442dd57 5336 while (!((pktin && pktin->type == SSH2_MSG_KEXINIT) ||
5337 (!pktin && inlen == -1))) {
f382c87d 5338 wait_for_rekey:
32874aea 5339 crReturn(1);
e96adf72 5340 }
9442dd57 5341 if (pktin) {
5342 logevent("Server initiated key re-exchange");
5343 } else {
f382c87d 5344 /*
5345 * Special case: if the server bug is set that doesn't
5346 * allow rekeying, we give a different log message and
5347 * continue waiting. (If such a server _initiates_ a rekey,
5348 * we process it anyway!)
5349 */
5350 if ((ssh->remote_bugs & BUG_SSH2_REKEY)) {
5351 logeventf(ssh, "Server bug prevents key re-exchange (%s)",
5352 (char *)in);
5353 /* Reset the counters, so that at least this message doesn't
5354 * hit the event log _too_ often. */
5355 ssh->outgoing_data_size = 0;
5356 ssh->incoming_data_size = 0;
5357 if (ssh->cfg.ssh_rekey_time != 0) {
5358 ssh->next_rekey =
5359 schedule_timer(ssh->cfg.ssh_rekey_time*60*TICKSPERSEC,
5360 ssh2_timer, ssh);
5361 }
5362 goto wait_for_rekey; /* this is utterly horrid */
5363 } else {
5364 logeventf(ssh, "Initiating key re-exchange (%s)", (char *)in);
f382c87d 5365 }
9442dd57 5366 }
7cca0d81 5367 goto begin_key_exchange;
e5574168 5368
5369 crFinish(1);
5370}
5371
7cca0d81 5372/*
783415f8 5373 * Add data to an SSH2 channel output buffer.
5374 */
32874aea 5375static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
5376 int len)
5377{
5471d09a 5378 bufchain_add(&c->v.v2.outbuffer, buf, len);
783415f8 5379}
5380
5381/*
5382 * Attempt to send data on an SSH2 channel.
5383 */
5471d09a 5384static int ssh2_try_send(struct ssh_channel *c)
32874aea 5385{
51470298 5386 Ssh ssh = c->ssh;
ff3187f6 5387 struct Packet *pktout;
51470298 5388
5471d09a 5389 while (c->v.v2.remwindow > 0 && bufchain_size(&c->v.v2.outbuffer) > 0) {
5390 int len;
5391 void *data;
5392 bufchain_prefix(&c->v.v2.outbuffer, &data, &len);
5393 if ((unsigned)len > c->v.v2.remwindow)
5394 len = c->v.v2.remwindow;
5395 if ((unsigned)len > c->v.v2.remmaxpkt)
5396 len = c->v.v2.remmaxpkt;
ff3187f6 5397 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
5398 ssh2_pkt_adduint32(pktout, c->remoteid);
5399 dont_log_data(ssh, pktout, PKTLOG_OMIT);
5400 ssh2_pkt_addstring_start(pktout);
5401 ssh2_pkt_addstring_data(pktout, data, len);
5402 end_log_omission(ssh, pktout);
5403 ssh2_pkt_send(ssh, pktout);
5471d09a 5404 bufchain_consume(&c->v.v2.outbuffer, len);
5405 c->v.v2.remwindow -= len;
5406 }
5407
5408 /*
5409 * After having sent as much data as we can, return the amount
5410 * still buffered.
5411 */
5412 return bufchain_size(&c->v.v2.outbuffer);
5413}
5414
5415/*
5416 * Potentially enlarge the window on an SSH2 channel.
5417 */
5418static void ssh2_set_window(struct ssh_channel *c, unsigned newwin)
5419{
51470298 5420 Ssh ssh = c->ssh;
5421
6b69f42e 5422 /*
5423 * Never send WINDOW_ADJUST for a channel that the remote side
5424 * already thinks it's closed; there's no point, since it won't
5425 * be sending any more data anyway.
5426 */
5427 if (c->closes != 0)
5428 return;
5429
5471d09a 5430 if (newwin > c->v.v2.locwindow) {
ff3187f6 5431 struct Packet *pktout;
5432
5433 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
5434 ssh2_pkt_adduint32(pktout, c->remoteid);
5435 ssh2_pkt_adduint32(pktout, newwin - c->v.v2.locwindow);
5436 ssh2_pkt_send(ssh, pktout);
5471d09a 5437 c->v.v2.locwindow = newwin;
783415f8 5438 }
5439}
5440
51df0ab5 5441static void ssh2_msg_channel_window_adjust(Ssh ssh, struct Packet *pktin)
b09eaa88 5442{
5443 unsigned i = ssh_pkt_getuint32(pktin);
5444 struct ssh_channel *c;
5445 c = find234(ssh->channels, &i, ssh_channelfind);
5446 if (c && !c->closes)
5447 c->v.v2.remwindow += ssh_pkt_getuint32(pktin);
5448}
5449
51df0ab5 5450static void ssh2_msg_channel_data(Ssh ssh, struct Packet *pktin)
5451{
5452 char *data;
aa63ab7e 5453 unsigned int length;
51df0ab5 5454 unsigned i = ssh_pkt_getuint32(pktin);
5455 struct ssh_channel *c;
5456 c = find234(ssh->channels, &i, ssh_channelfind);
5457 if (!c)
5458 return; /* nonexistent channel */
5459 if (pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
5460 ssh_pkt_getuint32(pktin) != SSH2_EXTENDED_DATA_STDERR)
5461 return; /* extended but not stderr */
5462 ssh_pkt_getstring(pktin, &data, &length);
5463 if (data) {
5464 int bufsize = 0;
5465 c->v.v2.locwindow -= length;
5466 switch (c->type) {
5467 case CHAN_MAINSESSION:
5468 bufsize =
5469 from_backend(ssh->frontend, pktin->type ==
5470 SSH2_MSG_CHANNEL_EXTENDED_DATA,
5471 data, length);
5472 break;
5473 case CHAN_X11:
5474 bufsize = x11_send(c->u.x11.s, data, length);
5475 break;
5476 case CHAN_SOCKDATA:
5477 bufsize = pfd_send(c->u.pfd.s, data, length);
5478 break;
5479 case CHAN_AGENT:
5480 while (length > 0) {
5481 if (c->u.a.lensofar < 4) {
aa63ab7e 5482 unsigned int l = min(4 - c->u.a.lensofar, length);
51df0ab5 5483 memcpy(c->u.a.msglen + c->u.a.lensofar,
5484 data, l);
5485 data += l;
5486 length -= l;
5487 c->u.a.lensofar += l;
5488 }
5489 if (c->u.a.lensofar == 4) {
5490 c->u.a.totallen =
5491 4 + GET_32BIT(c->u.a.msglen);
5492 c->u.a.message = snewn(c->u.a.totallen,
5493 unsigned char);
5494 memcpy(c->u.a.message, c->u.a.msglen, 4);
5495 }
5496 if (c->u.a.lensofar >= 4 && length > 0) {
aa63ab7e 5497 unsigned int l =
51df0ab5 5498 min(c->u.a.totallen - c->u.a.lensofar,
5499 length);
5500 memcpy(c->u.a.message + c->u.a.lensofar,
5501 data, l);
5502 data += l;
5503 length -= l;
5504 c->u.a.lensofar += l;
5505 }
5506 if (c->u.a.lensofar == c->u.a.totallen) {
5507 void *reply;
5508 int replylen;
5509 if (agent_query(c->u.a.message,
5510 c->u.a.totallen,
5511 &reply, &replylen,
5512 ssh_agentf_callback, c))
5513 ssh_agentf_callback(c, reply, replylen);
5514 sfree(c->u.a.message);
5515 c->u.a.lensofar = 0;
5516 }
5517 }
5518 bufsize = 0;
5519 break;
5520 }
5521 /*
5522 * If we are not buffering too much data,
5523 * enlarge the window again at the remote side.
5524 */
5525 if (bufsize < OUR_V2_WINSIZE)
5526 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
5527 }
5528}
5529
5530static void ssh2_msg_channel_eof(Ssh ssh, struct Packet *pktin)
5531{
5532 unsigned i = ssh_pkt_getuint32(pktin);
5533 struct ssh_channel *c;
5534
5535 c = find234(ssh->channels, &i, ssh_channelfind);
5536 if (!c)
5537 return; /* nonexistent channel */
5538
5539 if (c->type == CHAN_X11) {
5540 /*
5541 * Remote EOF on an X11 channel means we should
5542 * wrap up and close the channel ourselves.
5543 */
5544 x11_close(c->u.x11.s);
5545 sshfwd_close(c);
5546 } else if (c->type == CHAN_AGENT) {
5547 sshfwd_close(c);
5548 } else if (c->type == CHAN_SOCKDATA) {
5549 pfd_close(c->u.pfd.s);
5550 sshfwd_close(c);
5551 }
5552}
5553
5554static void ssh2_msg_channel_close(Ssh ssh, struct Packet *pktin)
5555{
5556 unsigned i = ssh_pkt_getuint32(pktin);
5557 struct ssh_channel *c;
5558 struct Packet *pktout;
5559
5560 c = find234(ssh->channels, &i, ssh_channelfind);
5561 if (!c || ((int)c->remoteid) == -1) {
5562 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5563 c ? "half-open" : "nonexistent", i));
5564 return;
5565 }
5566 /* Do pre-close processing on the channel. */
5567 switch (c->type) {
5568 case CHAN_MAINSESSION:
5569 ssh->mainchan = NULL;
5570 update_specials_menu(ssh->frontend);
5571 break;
5572 case CHAN_X11:
5573 if (c->u.x11.s != NULL)
5574 x11_close(c->u.x11.s);
5575 sshfwd_close(c);
5576 break;
5577 case CHAN_AGENT:
5578 sshfwd_close(c);
5579 break;
5580 case CHAN_SOCKDATA:
5581 if (c->u.pfd.s != NULL)
5582 pfd_close(c->u.pfd.s);
5583 sshfwd_close(c);
5584 break;
5585 }
5586 if (c->closes == 0) {
5587 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
5588 ssh2_pkt_adduint32(pktout, c->remoteid);
5589 ssh2_pkt_send(ssh, pktout);
5590 }
5591 del234(ssh->channels, c);
5592 bufchain_clear(&c->v.v2.outbuffer);
5593 sfree(c);
5594
5595 /*
5596 * See if that was the last channel left open.
5597 * (This is only our termination condition if we're
5598 * not running in -N mode.)
5599 */
5600 if (!ssh->cfg.ssh_no_shell && count234(ssh->channels) == 0) {
5601 logevent("All channels closed. Disconnecting");
5602#if 0
5603 /*
5604 * We used to send SSH_MSG_DISCONNECT here,
5605 * because I'd believed that _every_ conforming
5606 * SSH2 connection had to end with a disconnect
5607 * being sent by at least one side; apparently
5608 * I was wrong and it's perfectly OK to
5609 * unceremoniously slam the connection shut
5610 * when you're done, and indeed OpenSSH feels
5611 * this is more polite than sending a
5612 * DISCONNECT. So now we don't.
5613 */
5614 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
5615 ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
5616 ssh2_pkt_addstring(s->pktout, "All open channels closed");
5617 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
5618 ssh2_pkt_send_noqueue(ssh, s->pktout);
5619#endif
ac934965 5620 ssh->close_expected = TRUE;
51df0ab5 5621 ssh_closing((Plug)ssh, NULL, 0, 0);
5622 }
5623}
5624
5625static void ssh2_msg_channel_open_confirmation(Ssh ssh, struct Packet *pktin)
5626{
5627 unsigned i = ssh_pkt_getuint32(pktin);
5628 struct ssh_channel *c;
5629 struct Packet *pktout;
5630
5631 c = find234(ssh->channels, &i, ssh_channelfind);
5632 if (!c)
5633 return; /* nonexistent channel */
5634 if (c->type != CHAN_SOCKDATA_DORMANT)
5635 return; /* dunno why they're confirming this */
5636 c->remoteid = ssh_pkt_getuint32(pktin);
5637 c->type = CHAN_SOCKDATA;
5638 c->v.v2.remwindow = ssh_pkt_getuint32(pktin);
5639 c->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin);
5640 if (c->u.pfd.s)
5641 pfd_confirm(c->u.pfd.s);
5642 if (c->closes) {
5643 /*
5644 * We have a pending close on this channel,
5645 * which we decided on before the server acked
5646 * the channel open. So now we know the
5647 * remoteid, we can close it again.
5648 */
5649 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
5650 ssh2_pkt_adduint32(pktout, c->remoteid);
5651 ssh2_pkt_send(ssh, pktout);
5652 }
5653}
5654
5655static void ssh2_msg_channel_open_failure(Ssh ssh, struct Packet *pktin)
5656{
5657 static const char *const reasons[] = {
5658 "<unknown reason code>",
5659 "Administratively prohibited",
5660 "Connect failed",
5661 "Unknown channel type",
5662 "Resource shortage",
5663 };
5664 unsigned i = ssh_pkt_getuint32(pktin);
5665 unsigned reason_code;
5666 char *reason_string;
5667 int reason_length;
5668 char *message;
5669 struct ssh_channel *c;
5670 c = find234(ssh->channels, &i, ssh_channelfind);
5671 if (!c)
5672 return; /* nonexistent channel */
5673 if (c->type != CHAN_SOCKDATA_DORMANT)
5674 return; /* dunno why they're failing this */
5675
5676 reason_code = ssh_pkt_getuint32(pktin);
5677 if (reason_code >= lenof(reasons))
5678 reason_code = 0; /* ensure reasons[reason_code] in range */
5679 ssh_pkt_getstring(pktin, &reason_string, &reason_length);
5680 message = dupprintf("Forwarded connection refused by"
5681 " server: %s [%.*s]", reasons[reason_code],
5682 reason_length, reason_string);
5683 logevent(message);
5684 sfree(message);
5685
5686 pfd_close(c->u.pfd.s);
5687
5688 del234(ssh->channels, c);
5689 sfree(c);
5690}
5691
5692static void ssh2_msg_channel_request(Ssh ssh, struct Packet *pktin)
5693{
5694 unsigned localid;
5695 char *type;
5696 int typelen, want_reply;
5697 int reply = SSH2_MSG_CHANNEL_FAILURE; /* default */
5698 struct ssh_channel *c;
5699 struct Packet *pktout;
5700
5701 localid = ssh_pkt_getuint32(pktin);
5702 ssh_pkt_getstring(pktin, &type, &typelen);
5703 want_reply = ssh2_pkt_getbool(pktin);
5704
5705 /*
5706 * First, check that the channel exists. Otherwise,
5707 * we can instantly disconnect with a rude message.
5708 */
5709 c = find234(ssh->channels, &localid, ssh_channelfind);
5710 if (!c) {
5711 char buf[80];
5712 sprintf(buf, "Received channel request for nonexistent"
5713 " channel %d", localid);
5714 logevent(buf);
5715 pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
5716 ssh2_pkt_adduint32(pktout, SSH2_DISCONNECT_BY_APPLICATION);
5717 ssh2_pkt_addstring(pktout, buf);
5718 ssh2_pkt_addstring(pktout, "en"); /* language tag */
5719 ssh2_pkt_send_noqueue(ssh, pktout);
5720 connection_fatal(ssh->frontend, "%s", buf);
ac934965 5721 ssh->close_expected = TRUE;
51df0ab5 5722 ssh_closing((Plug)ssh, NULL, 0, 0);
5723 return;
5724 }
5725
5726 /*
5727 * Having got the channel number, we now look at
5728 * the request type string to see if it's something
5729 * we recognise.
5730 */
5731 if (c == ssh->mainchan) {
5732 /*
5733 * We recognise "exit-status" and "exit-signal" on
5734 * the primary channel.
5735 */
5736 if (typelen == 11 &&
5737 !memcmp(type, "exit-status", 11)) {
5738
5739 ssh->exitcode = ssh_pkt_getuint32(pktin);
5740 logeventf(ssh, "Server sent command exit status %d",
5741 ssh->exitcode);
5742 reply = SSH2_MSG_CHANNEL_SUCCESS;
5743
5744 } else if (typelen == 11 &&
5745 !memcmp(type, "exit-signal", 11)) {
5746
5747 int is_plausible = TRUE, is_int = FALSE;
5748 char *fmt_sig = "", *fmt_msg = "";
5749 char *msg;
5750 int msglen = 0, core = FALSE;
5751 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
5752 * provide an `int' for the signal, despite its
5753 * having been a `string' in the drafts since at
5754 * least 2001. (Fixed in session.c 1.147.) Try to
5755 * infer which we can safely parse it as. */
5756 {
5757 unsigned char *p = pktin->body +
5758 pktin->savedpos;
5759 long len = pktin->length - pktin->savedpos;
5760 unsigned long num = GET_32BIT(p); /* what is it? */
5761 /* If it's 0, it hardly matters; assume string */
5762 if (num == 0) {
5763 is_int = FALSE;
5764 } else {
5765 int maybe_int = FALSE, maybe_str = FALSE;
5766#define CHECK_HYPOTHESIS(offset, result) \
5767 do { \
5768 long q = offset; \
5769 if (q >= 0 && q+4 <= len) { \
5770 q = q + 4 + GET_32BIT(p+q); \
5771 if (q >= 0 && q+4 <= len && \
5772 (q = q + 4 + GET_32BIT(p+q)) && q == len) \
5773 result = TRUE; \
5774 } \
5775 } while(0)
5776 CHECK_HYPOTHESIS(4+1, maybe_int);
5777 CHECK_HYPOTHESIS(4+num+1, maybe_str);
5778#undef CHECK_HYPOTHESIS
5779 if (maybe_int && !maybe_str)
5780 is_int = TRUE;
5781 else if (!maybe_int && maybe_str)
5782 is_int = FALSE;
5783 else
5784 /* Crikey. Either or neither. Panic. */
5785 is_plausible = FALSE;
5786 }
5787 }
5788 if (is_plausible) {
5789 if (is_int) {
5790 /* Old non-standard OpenSSH. */
5791 int signum = ssh_pkt_getuint32(pktin);
5792 fmt_sig = dupprintf(" %d", signum);
5793 } else {
5794 /* As per the drafts. */
5795 char *sig;
5796 int siglen;
5797 ssh_pkt_getstring(pktin, &sig, &siglen);
5798 /* Signal name isn't supposed to be blank, but
5799 * let's cope gracefully if it is. */
5800 if (siglen) {
5801 fmt_sig = dupprintf(" \"%.*s\"",
5802 siglen, sig);
5803 }
5804 }
5805 core = ssh2_pkt_getbool(pktin);
5806 ssh_pkt_getstring(pktin, &msg, &msglen);
5807 if (msglen) {
5808 fmt_msg = dupprintf(" (\"%.*s\")", msglen, msg);
5809 }
5810 /* ignore lang tag */
5811 } /* else don't attempt to parse */
5812 logeventf(ssh, "Server exited on signal%s%s%s",
5813 fmt_sig, core ? " (core dumped)" : "",
5814 fmt_msg);
5815 if (*fmt_sig) sfree(fmt_sig);
5816 if (*fmt_msg) sfree(fmt_msg);
5817 reply = SSH2_MSG_CHANNEL_SUCCESS;
5818
5819 }
5820 } else {
5821 /*
5822 * This is a channel request we don't know
5823 * about, so we now either ignore the request
5824 * or respond with CHANNEL_FAILURE, depending
5825 * on want_reply.
5826 */
5827 reply = SSH2_MSG_CHANNEL_FAILURE;
5828 }
5829 if (want_reply) {
5830 pktout = ssh2_pkt_init(reply);
5831 ssh2_pkt_adduint32(pktout, c->remoteid);
5832 ssh2_pkt_send(ssh, pktout);
5833 }
5834}
5835
5836static void ssh2_msg_global_request(Ssh ssh, struct Packet *pktin)
5837{
5838 char *type;
5839 int typelen, want_reply;
5840 struct Packet *pktout;
5841
5842 ssh_pkt_getstring(pktin, &type, &typelen);
5843 want_reply = ssh2_pkt_getbool(pktin);
5844
5845 /*
5846 * We currently don't support any global requests
5847 * at all, so we either ignore the request or
5848 * respond with REQUEST_FAILURE, depending on
5849 * want_reply.
5850 */
5851 if (want_reply) {
5852 pktout = ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE);
5853 ssh2_pkt_send(ssh, pktout);
5854 }
5855}
5856
5857static void ssh2_msg_channel_open(Ssh ssh, struct Packet *pktin)
5858{
5859 char *type;
5860 int typelen;
5861 char *peeraddr;
5862 int peeraddrlen;
5863 int peerport;
5864 char *error = NULL;
5865 struct ssh_channel *c;
5866 unsigned remid, winsize, pktsize;
5867 struct Packet *pktout;
5868
5869 ssh_pkt_getstring(pktin, &type, &typelen);
5870 c = snew(struct ssh_channel);
5871 c->ssh = ssh;
5872
5873 remid = ssh_pkt_getuint32(pktin);
5874 winsize = ssh_pkt_getuint32(pktin);
5875 pktsize = ssh_pkt_getuint32(pktin);
5876
5877 if (typelen == 3 && !memcmp(type, "x11", 3)) {
5878 char *addrstr;
5879
5880 ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
5881 addrstr = snewn(peeraddrlen+1, char);
5882 memcpy(addrstr, peeraddr, peeraddrlen);
5883 addrstr[peeraddrlen] = '\0';
5884 peerport = ssh_pkt_getuint32(pktin);
5885
5886 logeventf(ssh, "Received X11 connect request from %s:%d",
5887 addrstr, peerport);
5888
5889 if (!ssh->X11_fwd_enabled)
5890 error = "X11 forwarding is not enabled";
5891 else if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
5892 ssh->x11auth, addrstr, peerport,
5893 &ssh->cfg) != NULL) {
5894 error = "Unable to open an X11 connection";
5895 } else {
5896 logevent("Opening X11 forward connection succeeded");
5897 c->type = CHAN_X11;
5898 }
5899
5900 sfree(addrstr);
5901 } else if (typelen == 15 &&
5902 !memcmp(type, "forwarded-tcpip", 15)) {
5903 struct ssh_rportfwd pf, *realpf;
5904 char *dummy;
5905 int dummylen;
5906 ssh_pkt_getstring(pktin, &dummy, &dummylen);/* skip address */
5907 pf.sport = ssh_pkt_getuint32(pktin);
5908 ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
5909 peerport = ssh_pkt_getuint32(pktin);
5910 realpf = find234(ssh->rportfwds, &pf, NULL);
5911 logeventf(ssh, "Received remote port %d open request "
5912 "from %s:%d", pf.sport, peeraddr, peerport);
5913 if (realpf == NULL) {
5914 error = "Remote port is not recognised";
5915 } else {
5916 const char *e = pfd_newconnect(&c->u.pfd.s,
5917 realpf->dhost,
5918 realpf->dport, c,
05581745 5919 &ssh->cfg,
5920 realpf->pfrec->addressfamily);
51df0ab5 5921 logeventf(ssh, "Attempting to forward remote port to "
5922 "%s:%d", realpf->dhost, realpf->dport);
5923 if (e != NULL) {
5924 logeventf(ssh, "Port open failed: %s", e);
5925 error = "Port open failed";
5926 } else {
5927 logevent("Forwarded port opened successfully");
5928 c->type = CHAN_SOCKDATA;
5929 }
5930 }
5931 } else if (typelen == 22 &&
5932 !memcmp(type, "auth-agent@openssh.com", 3)) {
5933 if (!ssh->agentfwd_enabled)
5934 error = "Agent forwarding is not enabled";
5935 else {
5936 c->type = CHAN_AGENT; /* identify channel type */
5937 c->u.a.lensofar = 0;
5938 }
5939 } else {
5940 error = "Unsupported channel type requested";
5941 }
5942
5943 c->remoteid = remid;
5944 if (error) {
5945 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE);
5946 ssh2_pkt_adduint32(pktout, c->remoteid);
5947 ssh2_pkt_adduint32(pktout, SSH2_OPEN_CONNECT_FAILED);
5948 ssh2_pkt_addstring(pktout, error);
5949 ssh2_pkt_addstring(pktout, "en"); /* language tag */
5950 ssh2_pkt_send(ssh, pktout);
5951 logeventf(ssh, "Rejected channel open: %s", error);
5952 sfree(c);
5953 } else {
5954 c->localid = alloc_channel_id(ssh);
5955 c->closes = 0;
5956 c->v.v2.locwindow = OUR_V2_WINSIZE;
5957 c->v.v2.remwindow = winsize;
5958 c->v.v2.remmaxpkt = pktsize;
5959 bufchain_init(&c->v.v2.outbuffer);
5960 add234(ssh->channels, c);
5961 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
5962 ssh2_pkt_adduint32(pktout, c->remoteid);
5963 ssh2_pkt_adduint32(pktout, c->localid);
5964 ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);
954d5c5a 5965 ssh2_pkt_adduint32(pktout, OUR_V2_MAXPKT); /* our max pkt size */
51df0ab5 5966 ssh2_pkt_send(ssh, pktout);
5967 }
5968}
5969
783415f8 5970/*
7cca0d81 5971 * Handle the SSH2 userauth and connection layers.
5972 */
ff3187f6 5973static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
5974 struct Packet *pktin)
7cca0d81 5975{
51470298 5976 struct do_ssh2_authconn_state {
5977 enum {
5978 AUTH_INVALID, AUTH_PUBLICKEY_AGENT, AUTH_PUBLICKEY_FILE,
5979 AUTH_PASSWORD,
5980 AUTH_KEYBOARD_INTERACTIVE
5981 } method;
5982 enum {
5983 AUTH_TYPE_NONE,
5984 AUTH_TYPE_PUBLICKEY,
5985 AUTH_TYPE_PUBLICKEY_OFFER_LOUD,
5986 AUTH_TYPE_PUBLICKEY_OFFER_QUIET,
5987 AUTH_TYPE_PASSWORD,
5988 AUTH_TYPE_KEYBOARD_INTERACTIVE,
5989 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
5990 } type;
5991 int gotit, need_pw, can_pubkey, can_passwd, can_keyb_inter;
6ac3a551 5992 int tried_pubkey_config, tried_agent;
5993 int kbd_inter_running, kbd_inter_refused;
51470298 5994 int we_are_in;
5995 int num_prompts, curr_prompt, echo;
5996 char username[100];
5997 int got_username;
85fdbe25 5998 char pwprompt[512];
51470298 5999 char password[100];
6000 void *publickey_blob;
6001 int publickey_bloblen;
6002 unsigned char request[5], *response, *p;
6003 int responselen;
6004 int keyi, nkeys;
6005 int authed;
6006 char *pkblob, *alg, *commentp;
6007 int pklen, alglen, commentlen;
6008 int siglen, retlen, len;
6009 char *q, *agentreq, *ret;
6010 int try_send;
73feed4f 6011 int num_env, env_left, env_ok;
ff3187f6 6012 struct Packet *pktout;
51470298 6013 };
6014 crState(do_ssh2_authconn_state);
6015
6016 crBegin(ssh->do_ssh2_authconn_crstate);
e5574168 6017
7cca0d81 6018 /*
6019 * Request userauth protocol, and await a response to it.
6020 */
ff3187f6 6021 s->pktout = ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
6022 ssh2_pkt_addstring(s->pktout, "ssh-userauth");
6023 ssh2_pkt_send(ssh, s->pktout);
6024 crWaitUntilV(pktin);
6025 if (pktin->type != SSH2_MSG_SERVICE_ACCEPT) {
6b5cf8b4 6026 bombout(("Server refused user authentication protocol"));
7ffdbc1a 6027 crStopV;
8d5de777 6028 }
7cca0d81 6029
6030 /*
1408a877 6031 * We repeat this whole loop, including the username prompt,
6032 * until we manage a successful authentication. If the user
51470298 6033 * types the wrong _password_, they can be sent back to the
6034 * beginning to try another username, if this is configured on.
6035 * (If they specify a username in the config, they are never
6036 * asked, even if they do give a wrong password.)
1408a877 6037 *
6038 * I think this best serves the needs of
6039 *
6040 * - the people who have no configuration, no keys, and just
6041 * want to try repeated (username,password) pairs until they
6042 * type both correctly
6043 *
6044 * - people who have keys and configuration but occasionally
6045 * need to fall back to passwords
6046 *
6047 * - people with a key held in Pageant, who might not have
6048 * logged in to a particular machine before; so they want to
6049 * type a username, and then _either_ their key will be
6050 * accepted, _or_ they will type a password. If they mistype
6051 * the username they will want to be able to get back and
6052 * retype it!
7cca0d81 6053 */
51470298 6054 s->username[0] = '\0';
6055 s->got_username = FALSE;
1408a877 6056 do {
1408a877 6057 /*
6058 * Get a username.
6059 */
86916870 6060 if (s->got_username && !ssh->cfg.change_username) {
5bb641e1 6061 /*
6062 * We got a username last time round this loop, and
6063 * with change_username turned off we don't try to get
6064 * it again.
6065 */
aa09f7d0 6066 } else if (!*ssh->cfg.username) {
c0a81592 6067 if (ssh_get_line && !ssh_getline_pw_only) {
32874aea 6068 if (!ssh_get_line("login as: ",
51470298 6069 s->username, sizeof(s->username), FALSE)) {
32874aea 6070 /*
6071 * get_line failed to get a username.
6072 * Terminate.
6073 */
6074 logevent("No username provided. Abandoning session.");
ac934965 6075 ssh->close_expected = TRUE;
3bb2f322 6076 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 6077 crStopV;
32874aea 6078 }
6079 } else {
51470298 6080 int ret; /* need not be saved across crReturn */
6081 c_write_str(ssh, "login as: ");
6082 ssh->send_ok = 1;
6083 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
0405e71f 6084 do {
ff3187f6 6085 crWaitUntilV(!pktin);
51470298 6086 ret = process_userpass_input(ssh, in, inlen);
0405e71f 6087 } while (ret == 0);
6088 if (ret < 0)
6089 cleanup_exit(0);
4ca0c9d1 6090 c_write_str(ssh, "\r\n");
32874aea 6091 }
51470298 6092 s->username[strcspn(s->username, "\n\r")] = '\0';
7cca0d81 6093 } else {
57356d63 6094 char *stuff;
86916870 6095 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
51470298 6096 s->username[sizeof(s->username)-1] = '\0';
65a22376 6097 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
57356d63 6098 stuff = dupprintf("Using username \"%s\".\r\n", s->username);
51470298 6099 c_write_str(ssh, stuff);
57356d63 6100 sfree(stuff);
7cca0d81 6101 }
6102 }
51470298 6103 s->got_username = TRUE;
7cca0d81 6104
65a22376 6105 /*
1408a877 6106 * Send an authentication request using method "none": (a)
6107 * just in case it succeeds, and (b) so that we know what
6108 * authentication methods we can usefully try next.
65a22376 6109 */
51470298 6110 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6111
ff3187f6 6112 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6113 ssh2_pkt_addstring(s->pktout, s->username);
6114 ssh2_pkt_addstring(s->pktout, "ssh-connection");/* service requested */
6115 ssh2_pkt_addstring(s->pktout, "none"); /* method */
6116 ssh2_pkt_send(ssh, s->pktout);
51470298 6117 s->type = AUTH_TYPE_NONE;
6118 s->gotit = FALSE;
6119 s->we_are_in = FALSE;
6120
6121 s->tried_pubkey_config = FALSE;
6122 s->tried_agent = FALSE;
51470298 6123 s->kbd_inter_running = FALSE;
6ac3a551 6124 s->kbd_inter_refused = FALSE;
86916870 6125 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
9a30e26b 6126 if (!filename_is_null(ssh->cfg.keyfile)) {
231ee168 6127 int keytype;
6c6d9ed9 6128 logeventf(ssh, "Reading private key file \"%.150s\"",
6129 filename_to_str(&ssh->cfg.keyfile));
9a30e26b 6130 keytype = key_type(&ssh->cfg.keyfile);
51470298 6131 if (keytype == SSH_KEYTYPE_SSH2) {
6132 s->publickey_blob =
9a30e26b 6133 ssh2_userkey_loadpub(&ssh->cfg.keyfile, NULL,
222d54dc 6134 &s->publickey_bloblen, NULL);
51470298 6135 } else {
57356d63 6136 char *msgbuf;
c2ad7d0d 6137 logeventf(ssh, "Unable to use this key file (%s)",
a8327734 6138 key_type_to_str(keytype));
57356d63 6139 msgbuf = dupprintf("Unable to use key file \"%.150s\""
6c6d9ed9 6140 " (%s)\r\n",
6141 filename_to_str(&ssh->cfg.keyfile),
57356d63 6142 key_type_to_str(keytype));
51470298 6143 c_write_str(ssh, msgbuf);
57356d63 6144 sfree(msgbuf);
51470298 6145 s->publickey_blob = NULL;
231ee168 6146 }
396778f1 6147 } else
51470298 6148 s->publickey_blob = NULL;
65a22376 6149
1408a877 6150 while (1) {
6151 /*
6152 * Wait for the result of the last authentication request.
6153 */
51470298 6154 if (!s->gotit)
ff3187f6 6155 crWaitUntilV(pktin);
6156 while (pktin->type == SSH2_MSG_USERAUTH_BANNER) {
32874aea 6157 char *banner;
6158 int size;
6159 /*
6160 * Don't show the banner if we're operating in
6161 * non-verbose non-interactive mode. (It's probably
6162 * a script, which means nobody will read the
6163 * banner _anyway_, and moreover the printing of
6164 * the banner will screw up processing on the
6165 * output of (say) plink.)
6166 */
6167 if (flags & (FLAG_VERBOSE | FLAG_INTERACTIVE)) {
ff3187f6 6168 ssh_pkt_getstring(pktin, &banner, &size);
32874aea 6169 if (banner)
51470298 6170 c_write_untrusted(ssh, banner, size);
32874aea 6171 }
ff3187f6 6172 crWaitUntilV(pktin);
1408a877 6173 }
ff3187f6 6174 if (pktin->type == SSH2_MSG_USERAUTH_SUCCESS) {
1408a877 6175 logevent("Access granted");
51470298 6176 s->we_are_in = TRUE;
1408a877 6177 break;
6178 }
65a22376 6179
51470298 6180 if (s->kbd_inter_running &&
ff3187f6 6181 pktin->type == SSH2_MSG_USERAUTH_INFO_REQUEST) {
b3186d64 6182 /*
45068b27 6183 * This is either a further set-of-prompts packet
6184 * in keyboard-interactive authentication, or it's
6185 * the same one and we came back here with `gotit'
6186 * set. In the former case, we must reset the
6187 * curr_prompt variable.
b3186d64 6188 */
51470298 6189 if (!s->gotit)
6190 s->curr_prompt = 0;
4c6e53e3 6191 } else if (pktin->type == SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ) {
6192 /* FIXME: perhaps we should support this? */
6193 bombout(("PASSWD_CHANGEREQ not yet supported"));
6194 crStopV;
ff3187f6 6195 } else if (pktin->type != SSH2_MSG_USERAUTH_FAILURE) {
6b5cf8b4 6196 bombout(("Strange packet received during authentication: type %d",
ff3187f6 6197 pktin->type));
7ffdbc1a 6198 crStopV;
65a22376 6199 }
6200
51470298 6201 s->gotit = FALSE;
65a22376 6202
1408a877 6203 /*
6204 * OK, we're now sitting on a USERAUTH_FAILURE message, so
6205 * we can look at the string in it and know what we can
6206 * helpfully try next.
6207 */
ff3187f6 6208 if (pktin->type == SSH2_MSG_USERAUTH_FAILURE) {
1408a877 6209 char *methods;
6210 int methlen;
ff3187f6 6211 ssh_pkt_getstring(pktin, &methods, &methlen);
51470298 6212 s->kbd_inter_running = FALSE;
ff3187f6 6213 if (!ssh2_pkt_getbool(pktin)) {
1408a877 6214 /*
6215 * We have received an unequivocal Access
6216 * Denied. This can translate to a variety of
6217 * messages:
6218 *
6219 * - if we'd just tried "none" authentication,
6220 * it's not worth printing anything at all
6221 *
6222 * - if we'd just tried a public key _offer_,
6223 * the message should be "Server refused our
6224 * key" (or no message at all if the key
6225 * came from Pageant)
6226 *
6227 * - if we'd just tried anything else, the
6228 * message really should be "Access denied".
6229 *
6230 * Additionally, if we'd just tried password
6231 * authentication, we should break out of this
6232 * whole loop so as to go back to the username
91f57d1f 6233 * prompt (iff we're configured to allow
6234 * username change attempts).
1408a877 6235 */
51470298 6236 if (s->type == AUTH_TYPE_NONE) {
1408a877 6237 /* do nothing */
51470298 6238 } else if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD ||
6239 s->type == AUTH_TYPE_PUBLICKEY_OFFER_QUIET) {
6240 if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD)
6241 c_write_str(ssh, "Server refused our key\r\n");
1408a877 6242 logevent("Server refused public key");
51470298 6243 } else if (s->type==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET) {
4bdf7c46 6244 /* server declined keyboard-interactive; ignore */
1408a877 6245 } else {
51470298 6246 c_write_str(ssh, "Access denied\r\n");
1408a877 6247 logevent("Access denied");
91f57d1f 6248 if (s->type == AUTH_TYPE_PASSWORD &&
6249 ssh->cfg.change_username) {
6c9dce7c 6250 /* XXX perhaps we should allow
6251 * keyboard-interactive to do this too? */
51470298 6252 s->we_are_in = FALSE;
1408a877 6253 break;
6254 }
6255 }
6256 } else {
51470298 6257 c_write_str(ssh, "Further authentication required\r\n");
1408a877 6258 logevent("Further authentication required");
6259 }
65a22376 6260
51470298 6261 s->can_pubkey =
32874aea 6262 in_commasep_string("publickey", methods, methlen);
51470298 6263 s->can_passwd =
32874aea 6264 in_commasep_string("password", methods, methlen);
86916870 6265 s->can_keyb_inter = ssh->cfg.try_ki_auth &&
761187b6 6266 in_commasep_string("keyboard-interactive", methods, methlen);
1408a877 6267 }
65a22376 6268
51470298 6269 s->method = 0;
6270 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
954a9540 6271 s->need_pw = FALSE;
65a22376 6272
0405e71f 6273 /*
6274 * Most password/passphrase prompts will be
6275 * non-echoing, so we set this to 0 by default.
6276 * Exception is that some keyboard-interactive prompts
6277 * can be echoing, in which case we'll set this to 1.
6278 */
51470298 6279 s->echo = 0;
0405e71f 6280
51470298 6281 if (!s->method && s->can_pubkey &&
6282 agent_exists() && !s->tried_agent) {
1983e559 6283 /*
6284 * Attempt public-key authentication using Pageant.
6285 */
1983e559 6286 void *r;
51470298 6287 s->authed = FALSE;
1983e559 6288
51470298 6289 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6290 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
00db133f 6291
51470298 6292 s->tried_agent = TRUE;
1983e559 6293
6294 logevent("Pageant is running. Requesting keys.");
6295
6296 /* Request the keys held by the agent. */
51470298 6297 PUT_32BIT(s->request, 1);
6298 s->request[4] = SSH2_AGENTC_REQUEST_IDENTITIES;
839f10db 6299 if (!agent_query(s->request, 5, &r, &s->responselen,
6300 ssh_agent_callback, ssh)) {
6301 do {
6302 crReturnV;
ff3187f6 6303 if (pktin) {
839f10db 6304 bombout(("Unexpected data from server while"
6305 " waiting for agent response"));
6306 crStopV;
6307 }
ff3187f6 6308 } while (pktin || inlen > 0);
839f10db 6309 r = ssh->agent_response;
6310 s->responselen = ssh->agent_response_len;
6311 }
51470298 6312 s->response = (unsigned char *) r;
6313 if (s->response && s->responselen >= 5 &&
6314 s->response[4] == SSH2_AGENT_IDENTITIES_ANSWER) {
6315 s->p = s->response + 5;
6316 s->nkeys = GET_32BIT(s->p);
6317 s->p += 4;
32874aea 6318 {
6319 char buf[64];
51470298 6320 sprintf(buf, "Pageant has %d SSH2 keys", s->nkeys);
32874aea 6321 logevent(buf);
6322 }
51470298 6323 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
2d466ffd 6324 void *vret;
1983e559 6325
32874aea 6326 {
6327 char buf[64];
51470298 6328 sprintf(buf, "Trying Pageant key #%d", s->keyi);
32874aea 6329 logevent(buf);
6330 }
51470298 6331 s->pklen = GET_32BIT(s->p);
6332 s->p += 4;
6333 if (s->publickey_blob &&
6334 s->pklen == s->publickey_bloblen &&
6335 !memcmp(s->p, s->publickey_blob,
6336 s->publickey_bloblen)) {
396778f1 6337 logevent("This key matches configured key file");
51470298 6338 s->tried_pubkey_config = 1;
396778f1 6339 }
d8baa528 6340 s->pkblob = (char *)s->p;
51470298 6341 s->p += s->pklen;
6342 s->alglen = GET_32BIT(s->pkblob);
6343 s->alg = s->pkblob + 4;
6344 s->commentlen = GET_32BIT(s->p);
6345 s->p += 4;
d8baa528 6346 s->commentp = (char *)s->p;
51470298 6347 s->p += s->commentlen;
ff3187f6 6348 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6349 ssh2_pkt_addstring(s->pktout, s->username);
6350 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6351 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6352 ssh2_pkt_addbool(s->pktout, FALSE); /* no signature included */
6353 ssh2_pkt_addstring_start(s->pktout);
6354 ssh2_pkt_addstring_data(s->pktout, s->alg, s->alglen);
6355 ssh2_pkt_addstring_start(s->pktout);
6356 ssh2_pkt_addstring_data(s->pktout, s->pkblob, s->pklen);
6357 ssh2_pkt_send(ssh, s->pktout);
6358
6359 crWaitUntilV(pktin);
6360 if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
1983e559 6361 logevent("Key refused");
6362 continue;
6363 }
6364
32874aea 6365 if (flags & FLAG_VERBOSE) {
51470298 6366 c_write_str(ssh, "Authenticating with "
6367 "public key \"");
6368 c_write(ssh, s->commentp, s->commentlen);
6369 c_write_str(ssh, "\" from agent\r\n");
32874aea 6370 }
1983e559 6371
6372 /*
6373 * Server is willing to accept the key.
6374 * Construct a SIGN_REQUEST.
6375 */
ff3187f6 6376 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6377 ssh2_pkt_addstring(s->pktout, s->username);
6378 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6379 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6380 ssh2_pkt_addbool(s->pktout, TRUE);
6381 ssh2_pkt_addstring_start(s->pktout);
6382 ssh2_pkt_addstring_data(s->pktout, s->alg, s->alglen);
6383 ssh2_pkt_addstring_start(s->pktout);
6384 ssh2_pkt_addstring_data(s->pktout, s->pkblob, s->pklen);
6385
6386 s->siglen = s->pktout->length - 5 + 4 + 20;
dda87a28 6387 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
6388 s->siglen -= 4;
51470298 6389 s->len = 1; /* message type */
6390 s->len += 4 + s->pklen; /* key blob */
6391 s->len += 4 + s->siglen; /* data to sign */
6392 s->len += 4; /* flags */
3d88e64d 6393 s->agentreq = snewn(4 + s->len, char);
51470298 6394 PUT_32BIT(s->agentreq, s->len);
6395 s->q = s->agentreq + 4;
6396 *s->q++ = SSH2_AGENTC_SIGN_REQUEST;
6397 PUT_32BIT(s->q, s->pklen);
6398 s->q += 4;
6399 memcpy(s->q, s->pkblob, s->pklen);
6400 s->q += s->pklen;
6401 PUT_32BIT(s->q, s->siglen);
6402 s->q += 4;
1983e559 6403 /* Now the data to be signed... */
dda87a28 6404 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
6405 PUT_32BIT(s->q, 20);
6406 s->q += 4;
6407 }
51470298 6408 memcpy(s->q, ssh->v2_session_id, 20);
6409 s->q += 20;
ff3187f6 6410 memcpy(s->q, s->pktout->data + 5,
6411 s->pktout->length - 5);
6412 s->q += s->pktout->length - 5;
1983e559 6413 /* And finally the (zero) flags word. */
51470298 6414 PUT_32BIT(s->q, 0);
839f10db 6415 if (!agent_query(s->agentreq, s->len + 4,
6416 &vret, &s->retlen,
6417 ssh_agent_callback, ssh)) {
6418 do {
6419 crReturnV;
ff3187f6 6420 if (pktin) {
839f10db 6421 bombout(("Unexpected data from server"
6422 " while waiting for agent"
6423 " response"));
6424 crStopV;
6425 }
ff3187f6 6426 } while (pktin || inlen > 0);
839f10db 6427 vret = ssh->agent_response;
6428 s->retlen = ssh->agent_response_len;
6429 }
51470298 6430 s->ret = vret;
6431 sfree(s->agentreq);
6432 if (s->ret) {
6433 if (s->ret[4] == SSH2_AGENT_SIGN_RESPONSE) {
1983e559 6434 logevent("Sending Pageant's response");
ff3187f6 6435 ssh2_add_sigblob(ssh, s->pktout,
6436 s->pkblob, s->pklen,
51470298 6437 s->ret + 9,
6438 GET_32BIT(s->ret + 5));
ff3187f6 6439 ssh2_pkt_send(ssh, s->pktout);
51470298 6440 s->authed = TRUE;
1983e559 6441 break;
6442 } else {
32874aea 6443 logevent
6444 ("Pageant failed to answer challenge");
51470298 6445 sfree(s->ret);
1983e559 6446 }
6447 }
6448 }
51470298 6449 if (s->authed)
1983e559 6450 continue;
6451 }
29b1d0b3 6452 sfree(s->response);
1983e559 6453 }
6454
51470298 6455 if (!s->method && s->can_pubkey && s->publickey_blob
6456 && !s->tried_pubkey_config) {
1408a877 6457 unsigned char *pub_blob;
6458 char *algorithm, *comment;
6459 int pub_blob_len;
65a22376 6460
51470298 6461 s->tried_pubkey_config = TRUE;
65a22376 6462
51470298 6463 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6464 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
00db133f 6465
65a22376 6466 /*
1408a877 6467 * Try the public key supplied in the configuration.
6468 *
6469 * First, offer the public blob to see if the server is
6470 * willing to accept it.
65a22376 6471 */
d8baa528 6472 pub_blob =
9a30e26b 6473 (unsigned char *)ssh2_userkey_loadpub(&ssh->cfg.keyfile,
d8baa528 6474 &algorithm,
222d54dc 6475 &pub_blob_len,
6476 NULL);
1408a877 6477 if (pub_blob) {
ff3187f6 6478 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6479 ssh2_pkt_addstring(s->pktout, s->username);
6480 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6481 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6482 ssh2_pkt_addbool(s->pktout, FALSE); /* no signature included */
6483 ssh2_pkt_addstring(s->pktout, algorithm);
6484 ssh2_pkt_addstring_start(s->pktout);
6485 ssh2_pkt_addstring_data(s->pktout, (char *)pub_blob,
d8baa528 6486 pub_blob_len);
ff3187f6 6487 ssh2_pkt_send(ssh, s->pktout);
a03c9f9c 6488 logevent("Offered public key");
1408a877 6489
ff3187f6 6490 crWaitUntilV(pktin);
6491 if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
51470298 6492 s->gotit = TRUE;
6493 s->type = AUTH_TYPE_PUBLICKEY_OFFER_LOUD;
32874aea 6494 continue; /* key refused; give up on it */
1408a877 6495 }
65a22376 6496
1408a877 6497 logevent("Offer of public key accepted");
65a22376 6498 /*
1408a877 6499 * Actually attempt a serious authentication using
6500 * the key.
65a22376 6501 */
9a30e26b 6502 if (ssh2_userkey_encrypted(&ssh->cfg.keyfile, &comment)) {
51470298 6503 sprintf(s->pwprompt,
32874aea 6504 "Passphrase for key \"%.100s\": ",
6505 comment);
51470298 6506 s->need_pw = TRUE;
1408a877 6507 } else {
51470298 6508 s->need_pw = FALSE;
1408a877 6509 }
4e520718 6510 if (flags & FLAG_VERBOSE) {
6511 c_write_str(ssh, "Authenticating with public key \"");
6512 c_write_str(ssh, comment);
6513 c_write_str(ssh, "\"\r\n");
6514 }
51470298 6515 s->method = AUTH_PUBLICKEY_FILE;
65a22376 6516 }
1408a877 6517 }
6518
6f64ce13 6519 if (!s->method && s->can_keyb_inter && !s->kbd_inter_refused &&
6520 !s->kbd_inter_running) {
51470298 6521 s->method = AUTH_KEYBOARD_INTERACTIVE;
6522 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
af659722 6523
51470298 6524 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6525 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
00db133f 6526
ff3187f6 6527 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6528 ssh2_pkt_addstring(s->pktout, s->username);
6529 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6530 ssh2_pkt_addstring(s->pktout, "keyboard-interactive"); /* method */
6531 ssh2_pkt_addstring(s->pktout, ""); /* lang */
6532 ssh2_pkt_addstring(s->pktout, "");
6533 ssh2_pkt_send(ssh, s->pktout);
6534
6535 crWaitUntilV(pktin);
6536 if (pktin->type != SSH2_MSG_USERAUTH_INFO_REQUEST) {
6537 if (pktin->type == SSH2_MSG_USERAUTH_FAILURE)
51470298 6538 s->gotit = TRUE;
af659722 6539 logevent("Keyboard-interactive authentication refused");
51470298 6540 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET;
6ac3a551 6541 s->kbd_inter_refused = TRUE; /* don't try it again */
af659722 6542 continue;
6543 }
6544
51470298 6545 s->kbd_inter_running = TRUE;
6546 s->curr_prompt = 0;
af659722 6547 }
6548
51470298 6549 if (s->kbd_inter_running) {
6550 s->method = AUTH_KEYBOARD_INTERACTIVE;
6551 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
af659722 6552
51470298 6553 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6554 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
00db133f 6555
51470298 6556 if (s->curr_prompt == 0) {
45068b27 6557 /*
6558 * We've got a fresh USERAUTH_INFO_REQUEST.
6559 * Display header data, and start going through
6560 * the prompts.
6561 */
6562 char *name, *inst, *lang;
6563 int name_len, inst_len, lang_len;
6564
ff3187f6 6565 ssh_pkt_getstring(pktin, &name, &name_len);
6566 ssh_pkt_getstring(pktin, &inst, &inst_len);
6567 ssh_pkt_getstring(pktin, &lang, &lang_len);
45068b27 6568 if (name_len > 0) {
51470298 6569 c_write_untrusted(ssh, name, name_len);
6570 c_write_str(ssh, "\r\n");
45068b27 6571 }
6572 if (inst_len > 0) {
51470298 6573 c_write_untrusted(ssh, inst, inst_len);
6574 c_write_str(ssh, "\r\n");
45068b27 6575 }
ff3187f6 6576 s->num_prompts = ssh_pkt_getuint32(pktin);
45068b27 6577 }
af659722 6578
45068b27 6579 /*
6580 * If there are prompts remaining in the packet,
6581 * display one and get a response.
6582 */
51470298 6583 if (s->curr_prompt < s->num_prompts) {
45068b27 6584 char *prompt;
6585 int prompt_len;
af659722 6586
ff3187f6 6587 ssh_pkt_getstring(pktin, &prompt, &prompt_len);
45068b27 6588 if (prompt_len > 0) {
85fdbe25 6589 static const char trunc[] = "<prompt truncated>: ";
6590 static const int prlen = sizeof(s->pwprompt) -
6591 lenof(trunc);
6592 if (prompt_len > prlen) {
6593 memcpy(s->pwprompt, prompt, prlen);
6594 strcpy(s->pwprompt + prlen, trunc);
6595 } else {
6596 memcpy(s->pwprompt, prompt, prompt_len);
6597 s->pwprompt[prompt_len] = '\0';
6598 }
45068b27 6599 } else {
51470298 6600 strcpy(s->pwprompt,
45068b27 6601 "<server failed to send prompt>: ");
6602 }
ff3187f6 6603 s->echo = ssh2_pkt_getbool(pktin);
51470298 6604 s->need_pw = TRUE;
45068b27 6605 } else
51470298 6606 s->need_pw = FALSE;
af659722 6607 }
6608
51470298 6609 if (!s->method && s->can_passwd) {
6610 s->method = AUTH_PASSWORD;
6611 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6612 ssh->pkt_ctx |= SSH2_PKTCTX_PASSWORD;
6613 sprintf(s->pwprompt, "%.90s@%.90s's password: ", s->username,
6614 ssh->savedhost);
6615 s->need_pw = TRUE;
1408a877 6616 }
6617
51470298 6618 if (s->need_pw) {
fa17a66e 6619 if (ssh_get_line) {
51470298 6620 if (!ssh_get_line(s->pwprompt, s->password,
6621 sizeof(s->password), TRUE)) {
1408a877 6622 /*
fa17a66e 6623 * get_line failed to get a password (for
6624 * example because one was supplied on the
6625 * command line which has already failed to
6626 * work). Terminate.
1408a877 6627 */
ff3187f6 6628 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
6629 ssh2_pkt_adduint32(s->pktout,SSH2_DISCONNECT_BY_APPLICATION);
6630 ssh2_pkt_addstring(s->pktout, "No more passwords available"
51470298 6631 " to try");
ff3187f6 6632 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
590f6a5f 6633 ssh2_pkt_send_noqueue(ssh, s->pktout);
247308b5 6634 logevent("Unable to authenticate");
a8327734 6635 connection_fatal(ssh->frontend,
6636 "Unable to authenticate");
ac934965 6637 ssh->close_expected = TRUE;
3bb2f322 6638 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 6639 crStopV;
1408a877 6640 }
6641 } else {
51470298 6642 int ret; /* need not be saved across crReturn */
6643 c_write_untrusted(ssh, s->pwprompt, strlen(s->pwprompt));
6644 ssh->send_ok = 1;
1408a877 6645
51470298 6646 setup_userpass_input(ssh, s->password,
6647 sizeof(s->password), s->echo);
0405e71f 6648 do {
ff3187f6 6649 crWaitUntilV(!pktin);
51470298 6650 ret = process_userpass_input(ssh, in, inlen);
0405e71f 6651 } while (ret == 0);
6652 if (ret < 0)
6653 cleanup_exit(0);
51470298 6654 c_write_str(ssh, "\r\n");
65a22376 6655 }
65a22376 6656 }
65a22376 6657
51470298 6658 if (s->method == AUTH_PUBLICKEY_FILE) {
1408a877 6659 /*
6660 * We have our passphrase. Now try the actual authentication.
6661 */
6662 struct ssh2_userkey *key;
222d54dc 6663 const char *error = NULL;
65a22376 6664
222d54dc 6665 key = ssh2_load_userkey(&ssh->cfg.keyfile, s->password,
6666 &error);
1408a877 6667 if (key == SSH2_WRONG_PASSPHRASE || key == NULL) {
6668 if (key == SSH2_WRONG_PASSPHRASE) {
51470298 6669 c_write_str(ssh, "Wrong passphrase\r\n");
6670 s->tried_pubkey_config = FALSE;
1408a877 6671 } else {
222d54dc 6672 c_write_str(ssh, "Unable to load private key (");
6673 c_write_str(ssh, error);
6674 c_write_str(ssh, ")\r\n");
51470298 6675 s->tried_pubkey_config = TRUE;
1408a877 6676 }
6677 /* Send a spurious AUTH_NONE to return to the top. */
ff3187f6 6678 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6679 ssh2_pkt_addstring(s->pktout, s->username);
6680 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6681 ssh2_pkt_addstring(s->pktout, "none"); /* method */
6682 ssh2_pkt_send(ssh, s->pktout);
51470298 6683 s->type = AUTH_TYPE_NONE;
1408a877 6684 } else {
1dd353b5 6685 unsigned char *pkblob, *sigblob, *sigdata;
6686 int pkblob_len, sigblob_len, sigdata_len;
dda87a28 6687 int p;
65a22376 6688
1408a877 6689 /*
6690 * We have loaded the private key and the server
6691 * has announced that it's willing to accept it.
6692 * Hallelujah. Generate a signature and send it.
6693 */
ff3187f6 6694 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6695 ssh2_pkt_addstring(s->pktout, s->username);
6696 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6697 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6698 ssh2_pkt_addbool(s->pktout, TRUE);
6699 ssh2_pkt_addstring(s->pktout, key->alg->name);
1dd353b5 6700 pkblob = key->alg->public_blob(key->data, &pkblob_len);
ff3187f6 6701 ssh2_pkt_addstring_start(s->pktout);
6702 ssh2_pkt_addstring_data(s->pktout, (char *)pkblob, pkblob_len);
1408a877 6703
6704 /*
6705 * The data to be signed is:
6706 *
6707 * string session-id
6708 *
6709 * followed by everything so far placed in the
6710 * outgoing packet.
6711 */
ff3187f6 6712 sigdata_len = s->pktout->length - 5 + 4 + 20;
dda87a28 6713 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
6714 sigdata_len -= 4;
92d60585 6715 sigdata = snewn(sigdata_len, unsigned char);
dda87a28 6716 p = 0;
6717 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
6718 PUT_32BIT(sigdata+p, 20);
6719 p += 4;
6720 }
6721 memcpy(sigdata+p, ssh->v2_session_id, 20); p += 20;
ff3187f6 6722 memcpy(sigdata+p, s->pktout->data + 5,
6723 s->pktout->length - 5);
6724 p += s->pktout->length - 5;
dda87a28 6725 assert(p == sigdata_len);
d8baa528 6726 sigblob = key->alg->sign(key->data, (char *)sigdata,
1dd353b5 6727 sigdata_len, &sigblob_len);
ff3187f6 6728 ssh2_add_sigblob(ssh, s->pktout, pkblob, pkblob_len,
1dd353b5 6729 sigblob, sigblob_len);
6730 sfree(pkblob);
6731 sfree(sigblob);
1408a877 6732 sfree(sigdata);
6733
ff3187f6 6734 ssh2_pkt_send(ssh, s->pktout);
51470298 6735 s->type = AUTH_TYPE_PUBLICKEY;
75374b2f 6736 key->alg->freekey(key->data);
1408a877 6737 }
51470298 6738 } else if (s->method == AUTH_PASSWORD) {
65a22376 6739 /*
1408a877 6740 * We send the password packet lumped tightly together with
6741 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
6742 * string long enough to make the total length of the two
6743 * packets constant. This should ensure that a passive
6744 * listener doing traffic analyis can't work out the length
6745 * of the password.
6746 *
6747 * For this to work, we need an assumption about the
6748 * maximum length of the password packet. I think 256 is
6749 * pretty conservative. Anyone using a password longer than
6750 * that probably doesn't have much to worry about from
6751 * people who find out how long their password is!
65a22376 6752 */
ff3187f6 6753 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6754 ssh2_pkt_addstring(s->pktout, s->username);
6755 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6756 ssh2_pkt_addstring(s->pktout, "password");
6757 ssh2_pkt_addbool(s->pktout, FALSE);
6758 dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
6759 ssh2_pkt_addstring(s->pktout, s->password);
1409c1b3 6760 memset(s->password, 0, sizeof(s->password));
ff3187f6 6761 end_log_omission(ssh, s->pktout);
6762 ssh2_pkt_defer(ssh, s->pktout);
65a22376 6763 /*
1408a877 6764 * We'll include a string that's an exact multiple of the
6765 * cipher block size. If the cipher is NULL for some
6766 * reason, we don't do this trick at all because we gain
6767 * nothing by it.
65a22376 6768 */
51470298 6769 if (ssh->cscipher) {
32874aea 6770 int stringlen, i;
6771
51470298 6772 stringlen = (256 - ssh->deferred_len);
6773 stringlen += ssh->cscipher->blksize - 1;
6774 stringlen -= (stringlen % ssh->cscipher->blksize);
6775 if (ssh->cscomp) {
32874aea 6776 /*
6777 * Temporarily disable actual compression,
6778 * so we can guarantee to get this string
6779 * exactly the length we want it. The
6780 * compression-disabling routine should
6781 * return an integer indicating how many
6782 * bytes we should adjust our string length
6783 * by.
6784 */
5366aed8 6785 stringlen -=
6786 ssh->cscomp->disable_compression(ssh->cs_comp_ctx);
32874aea 6787 }
ff3187f6 6788 s->pktout = ssh2_pkt_init(SSH2_MSG_IGNORE);
6789 ssh2_pkt_addstring_start(s->pktout);
6e9e9520 6790 for (i = 0; i < stringlen; i++) {
32874aea 6791 char c = (char) random_byte();
ff3187f6 6792 ssh2_pkt_addstring_data(s->pktout, &c, 1);
65a22376 6793 }
ff3187f6 6794 ssh2_pkt_defer(ssh, s->pktout);
65a22376 6795 }
51470298 6796 ssh_pkt_defersend(ssh);
0d43337a 6797 logevent("Sent password");
51470298 6798 s->type = AUTH_TYPE_PASSWORD;
6799 } else if (s->method == AUTH_KEYBOARD_INTERACTIVE) {
6800 if (s->curr_prompt == 0) {
ff3187f6 6801 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE);
6802 ssh2_pkt_adduint32(s->pktout, s->num_prompts);
45068b27 6803 }
51470298 6804 if (s->need_pw) { /* only add pw if we just got one! */
ff3187f6 6805 dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
6806 ssh2_pkt_addstring(s->pktout, s->password);
51470298 6807 memset(s->password, 0, sizeof(s->password));
ff3187f6 6808 end_log_omission(ssh, s->pktout);
51470298 6809 s->curr_prompt++;
45068b27 6810 }
51470298 6811 if (s->curr_prompt >= s->num_prompts) {
ff3187f6 6812 ssh2_pkt_send(ssh, s->pktout);
45068b27 6813 } else {
6814 /*
6815 * If there are prompts remaining, we set
6816 * `gotit' so that we won't attempt to get
6817 * another packet. Then we go back round the
6818 * loop and will end up retrieving another
6819 * prompt out of the existing packet. Funky or
6820 * what?
6821 */
51470298 6822 s->gotit = TRUE;
45068b27 6823 }
51470298 6824 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
1408a877 6825 } else {
51470298 6826 c_write_str(ssh, "No supported authentication methods"
6827 " left to try!\r\n");
6828 logevent("No supported authentications offered."
6829 " Disconnecting");
ff3187f6 6830 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
6831 ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
6832 ssh2_pkt_addstring(s->pktout, "No supported authentication"
51470298 6833 " methods available");
ff3187f6 6834 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
590f6a5f 6835 ssh2_pkt_send_noqueue(ssh, s->pktout);
ac934965 6836 ssh->close_expected = TRUE;
3bb2f322 6837 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 6838 crStopV;
65a22376 6839 }
65a22376 6840 }
51470298 6841 } while (!s->we_are_in);
7cca0d81 6842
6843 /*
6844 * Now we're authenticated for the connection protocol. The
6845 * connection protocol will automatically have started at this
6846 * point; there's no need to send SERVICE_REQUEST.
6847 */
6848
0ed48730 6849 ssh->channels = newtree234(ssh_channelcmp);
6850
7cca0d81 6851 /*
b09eaa88 6852 * Set up handlers for some connection protocol messages, so we
6853 * don't have to handle them repeatedly in this coroutine.
6854 */
6855 ssh->packet_dispatch[SSH2_MSG_CHANNEL_WINDOW_ADJUST] =
6856 ssh2_msg_channel_window_adjust;
51df0ab5 6857 ssh->packet_dispatch[SSH2_MSG_GLOBAL_REQUEST] =
6858 ssh2_msg_global_request;
b09eaa88 6859
6860 /*
0ed48730 6861 * Create the main session channel.
7cca0d81 6862 */
0ed48730 6863 if (!ssh->cfg.ssh_no_shell) {
6864 ssh->mainchan = snew(struct ssh_channel);
6865 ssh->mainchan->ssh = ssh;
6866 ssh->mainchan->localid = alloc_channel_id(ssh);
ff3187f6 6867 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
6868 ssh2_pkt_addstring(s->pktout, "session");
6869 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->localid);
0ed48730 6870 ssh->mainchan->v.v2.locwindow = OUR_V2_WINSIZE;
ff3187f6 6871 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->v.v2.locwindow);/* our window size */
954d5c5a 6872 ssh2_pkt_adduint32(s->pktout, OUR_V2_MAXPKT); /* our max pkt size */
ff3187f6 6873 ssh2_pkt_send(ssh, s->pktout);
6874 crWaitUntilV(pktin);
6875 if (pktin->type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
0ed48730 6876 bombout(("Server refused to open a session"));
6877 crStopV;
6878 /* FIXME: error data comes back in FAILURE packet */
6879 }
ff3187f6 6880 if (ssh_pkt_getuint32(pktin) != ssh->mainchan->localid) {
0ed48730 6881 bombout(("Server's channel confirmation cited wrong channel"));
6882 crStopV;
6883 }
ff3187f6 6884 ssh->mainchan->remoteid = ssh_pkt_getuint32(pktin);
0ed48730 6885 ssh->mainchan->type = CHAN_MAINSESSION;
6886 ssh->mainchan->closes = 0;
ff3187f6 6887 ssh->mainchan->v.v2.remwindow = ssh_pkt_getuint32(pktin);
6888 ssh->mainchan->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin);
0ed48730 6889 bufchain_init(&ssh->mainchan->v.v2.outbuffer);
6890 add234(ssh->channels, ssh->mainchan);
62638676 6891 update_specials_menu(ssh->frontend);
0ed48730 6892 logevent("Opened channel for session");
6893 } else
6894 ssh->mainchan = NULL;
7cca0d81 6895
6896 /*
51df0ab5 6897 * Now we have a channel, make dispatch table entries for
6898 * general channel-based messages.
6899 */
6900 ssh->packet_dispatch[SSH2_MSG_CHANNEL_DATA] =
6901 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EXTENDED_DATA] =
6902 ssh2_msg_channel_data;
6903 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EOF] = ssh2_msg_channel_eof;
6904 ssh->packet_dispatch[SSH2_MSG_CHANNEL_CLOSE] = ssh2_msg_channel_close;
6905 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION] =
6906 ssh2_msg_channel_open_confirmation;
6907 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_FAILURE] =
6908 ssh2_msg_channel_open_failure;
6909 ssh->packet_dispatch[SSH2_MSG_CHANNEL_REQUEST] =
6910 ssh2_msg_channel_request;
6911 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN] =
6912 ssh2_msg_channel_open;
6913
6914 /*
783415f8 6915 * Potentially enable X11 forwarding.
6916 */
0ed48730 6917 if (ssh->mainchan && ssh->cfg.x11_forward) {
32874aea 6918 char proto[20], data[64];
6919 logevent("Requesting X11 forwarding");
302121de 6920 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
86916870 6921 data, sizeof(data), ssh->cfg.x11_auth);
6922 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
ff3187f6 6923 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
6924 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
6925 ssh2_pkt_addstring(s->pktout, "x11-req");
6926 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
6927 ssh2_pkt_addbool(s->pktout, 0); /* many connections */
6928 ssh2_pkt_addstring(s->pktout, proto);
6929 ssh2_pkt_addstring(s->pktout, data);
6930 ssh2_pkt_adduint32(s->pktout, x11_get_screen_number(ssh->cfg.x11_display));
6931 ssh2_pkt_send(ssh, s->pktout);
32874aea 6932
b09eaa88 6933 crWaitUntilV(pktin);
32874aea 6934
ff3187f6 6935 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
6936 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 6937 bombout(("Unexpected response to X11 forwarding request:"
ff3187f6 6938 " packet type %d", pktin->type));
7ffdbc1a 6939 crStopV;
32874aea 6940 }
6941 logevent("X11 forwarding refused");
6942 } else {
6943 logevent("X11 forwarding enabled");
51470298 6944 ssh->X11_fwd_enabled = TRUE;
32874aea 6945 }
783415f8 6946 }
6947
6948 /*
bc240b21 6949 * Enable port forwardings.
6950 */
06fadff5 6951 ssh_setup_portfwd(ssh, &ssh->cfg);
bc240b21 6952
6953 /*
36c2a3e9 6954 * Potentially enable agent forwarding.
6955 */
0ed48730 6956 if (ssh->mainchan && ssh->cfg.agentfwd && agent_exists()) {
32874aea 6957 logevent("Requesting OpenSSH-style agent forwarding");
ff3187f6 6958 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
6959 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
6960 ssh2_pkt_addstring(s->pktout, "auth-agent-req@openssh.com");
6961 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
6962 ssh2_pkt_send(ssh, s->pktout);
32874aea 6963
b09eaa88 6964 crWaitUntilV(pktin);
32874aea 6965
ff3187f6 6966 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
6967 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 6968 bombout(("Unexpected response to agent forwarding request:"
ff3187f6 6969 " packet type %d", pktin->type));
7ffdbc1a 6970 crStopV;
32874aea 6971 }
6972 logevent("Agent forwarding refused");
6973 } else {
6974 logevent("Agent forwarding enabled");
51470298 6975 ssh->agentfwd_enabled = TRUE;
32874aea 6976 }
36c2a3e9 6977 }
6978
6979 /*
7cca0d81 6980 * Now allocate a pty for the session.
6981 */
0ed48730 6982 if (ssh->mainchan && !ssh->cfg.nopty) {
a5dd8467 6983 /* Unpick the terminal-speed string. */
6984 /* XXX perhaps we should allow no speeds to be sent. */
db219738 6985 ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
6986 sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
a5dd8467 6987 /* Build the pty request. */
ff3187f6 6988 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
6989 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid); /* recipient channel */
6990 ssh2_pkt_addstring(s->pktout, "pty-req");
6991 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
6992 ssh2_pkt_addstring(s->pktout, ssh->cfg.termtype);
6993 ssh2_pkt_adduint32(s->pktout, ssh->term_width);
6994 ssh2_pkt_adduint32(s->pktout, ssh->term_height);
6995 ssh2_pkt_adduint32(s->pktout, 0); /* pixel width */
6996 ssh2_pkt_adduint32(s->pktout, 0); /* pixel height */
6997 ssh2_pkt_addstring_start(s->pktout);
6998 ssh2_pkt_addbyte(s->pktout, 128); /* TTY_OP_ISPEED */
6999 ssh2_pkt_adduint32(s->pktout, ssh->ispeed);
7000 ssh2_pkt_addbyte(s->pktout, 129); /* TTY_OP_OSPEED */
7001 ssh2_pkt_adduint32(s->pktout, ssh->ospeed);
7002 ssh2_pkt_addstring_data(s->pktout, "\0", 1); /* TTY_OP_END */
7003 ssh2_pkt_send(ssh, s->pktout);
51470298 7004 ssh->state = SSH_STATE_INTERMED;
32874aea 7005
b09eaa88 7006 crWaitUntilV(pktin);
32874aea 7007
ff3187f6 7008 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
7009 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 7010 bombout(("Unexpected response to pty request:"
ff3187f6 7011 " packet type %d", pktin->type));
7ffdbc1a 7012 crStopV;
32874aea 7013 }
51470298 7014 c_write_str(ssh, "Server refused to allocate pty\r\n");
7015 ssh->editing = ssh->echoing = 1;
32874aea 7016 } else {
a5dd8467 7017 logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
db219738 7018 ssh->ospeed, ssh->ispeed);
32874aea 7019 }
0965bee0 7020 } else {
51470298 7021 ssh->editing = ssh->echoing = 1;
7cca0d81 7022 }
7023
7024 /*
73feed4f 7025 * Send environment variables.
7026 *
7027 * Simplest thing here is to send all the requests at once, and
7028 * then wait for a whole bunch of successes or failures.
7029 */
7030 if (ssh->mainchan && *ssh->cfg.environmt) {
7031 char *e = ssh->cfg.environmt;
7032 char *var, *varend, *val;
7033
7034 s->num_env = 0;
7035
7036 while (*e) {
7037 var = e;
7038 while (*e && *e != '\t') e++;
7039 varend = e;
7040 if (*e == '\t') e++;
7041 val = e;
7042 while (*e) e++;
7043 e++;
7044
ff3187f6 7045 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7046 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
7047 ssh2_pkt_addstring(s->pktout, "env");
7048 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7049 ssh2_pkt_addstring_start(s->pktout);
7050 ssh2_pkt_addstring_data(s->pktout, var, varend-var);
7051 ssh2_pkt_addstring(s->pktout, val);
7052 ssh2_pkt_send(ssh, s->pktout);
73feed4f 7053
7054 s->num_env++;
7055 }
7056
7057 logeventf(ssh, "Sent %d environment variables", s->num_env);
7058
7059 s->env_ok = 0;
7060 s->env_left = s->num_env;
7061
7062 while (s->env_left > 0) {
b09eaa88 7063 crWaitUntilV(pktin);
73feed4f 7064
ff3187f6 7065 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
7066 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
73feed4f 7067 bombout(("Unexpected response to environment request:"
ff3187f6 7068 " packet type %d", pktin->type));
73feed4f 7069 crStopV;
7070 }
7071 } else {
7072 s->env_ok++;
7073 }
7074
7075 s->env_left--;
7076 }
7077
7078 if (s->env_ok == s->num_env) {
7079 logevent("All environment variables successfully set");
7080 } else if (s->env_ok == 0) {
7081 logevent("All environment variables refused");
7082 c_write_str(ssh, "Server refused to set environment variables\r\n");
7083 } else {
7084 logeventf(ssh, "%d environment variables refused",
7085 s->num_env - s->env_ok);
7086 c_write_str(ssh, "Server refused to set all environment variables\r\n");
7087 }
7088 }
7089
7090 /*
fd5e5847 7091 * Start a shell or a remote command. We may have to attempt
7092 * this twice if the config data has provided a second choice
7093 * of command.
7cca0d81 7094 */
0ed48730 7095 if (ssh->mainchan) while (1) {
fd5e5847 7096 int subsys;
7097 char *cmd;
7098
51470298 7099 if (ssh->fallback_cmd) {
86916870 7100 subsys = ssh->cfg.ssh_subsys2;
7101 cmd = ssh->cfg.remote_cmd_ptr2;
fd5e5847 7102 } else {
86916870 7103 subsys = ssh->cfg.ssh_subsys;
7104 cmd = ssh->cfg.remote_cmd_ptr;
fd5e5847 7105 }
7106
ff3187f6 7107 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7108 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid); /* recipient channel */
fd5e5847 7109 if (subsys) {
ff3187f6 7110 ssh2_pkt_addstring(s->pktout, "subsystem");
7111 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7112 ssh2_pkt_addstring(s->pktout, cmd);
fd5e5847 7113 } else if (*cmd) {
ff3187f6 7114 ssh2_pkt_addstring(s->pktout, "exec");
7115 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7116 ssh2_pkt_addstring(s->pktout, cmd);
fd5e5847 7117 } else {
ff3187f6 7118 ssh2_pkt_addstring(s->pktout, "shell");
7119 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
32874aea 7120 }
ff3187f6 7121 ssh2_pkt_send(ssh, s->pktout);
b09eaa88 7122
7123 crWaitUntilV(pktin);
7124
ff3187f6 7125 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
7126 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 7127 bombout(("Unexpected response to shell/command request:"
ff3187f6 7128 " packet type %d", pktin->type));
7ffdbc1a 7129 crStopV;
fd5e5847 7130 }
7131 /*
7132 * We failed to start the command. If this is the
7133 * fallback command, we really are finished; if it's
7134 * not, and if the fallback command exists, try falling
7135 * back to it before complaining.
7136 */
86916870 7137 if (!ssh->fallback_cmd && ssh->cfg.remote_cmd_ptr2 != NULL) {
fd5e5847 7138 logevent("Primary command failed; attempting fallback");
51470298 7139 ssh->fallback_cmd = TRUE;
fd5e5847 7140 continue;
7141 }
6b5cf8b4 7142 bombout(("Server refused to start a shell/command"));
7ffdbc1a 7143 crStopV;
fd5e5847 7144 } else {
7145 logevent("Started a shell/command");
32874aea 7146 }
fd5e5847 7147 break;
7cca0d81 7148 }
7149
51470298 7150 ssh->state = SSH_STATE_SESSION;
7151 if (ssh->size_needed)
7152 ssh_size(ssh, ssh->term_width, ssh->term_height);
7153 if (ssh->eof_needed)
7154 ssh_special(ssh, TS_EOF);
6e48c3fe 7155
7cca0d81 7156 /*
7157 * Transfer data!
7158 */
b9d7bcad 7159 if (ssh->ldisc)
7160 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
0ed48730 7161 if (ssh->mainchan)
7162 ssh->send_ok = 1;
7cca0d81 7163 while (1) {
e5574168 7164 crReturnV;
51470298 7165 s->try_send = FALSE;
ff3187f6 7166 if (pktin) {
2b7540a7 7167
51df0ab5 7168 /*
7169 * _All_ the connection-layer packets we expect to
7170 * receive are now handled by the dispatch table.
7171 * Anything that reaches here must be bogus.
7172 */
32874aea 7173
51df0ab5 7174 bombout(("Strange packet received: type %d", pktin->type));
7175 crStopV;
0ed48730 7176 } else if (ssh->mainchan) {
32874aea 7177 /*
7178 * We have spare data. Add it to the channel buffer.
7179 */
d8baa528 7180 ssh2_add_channel_data(ssh->mainchan, (char *)in, inlen);
51470298 7181 s->try_send = TRUE;
32874aea 7182 }
51470298 7183 if (s->try_send) {
32874aea 7184 int i;
7185 struct ssh_channel *c;
7186 /*
7187 * Try to send data on all channels if we can.
7188 */
51470298 7189 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
a6253970 7190 int bufsize;
7191 if (c->closes)
7192 continue; /* don't send on closing channels */
7193 bufsize = ssh2_try_send(c);
5471d09a 7194 if (bufsize == 0) {
7195 switch (c->type) {
7196 case CHAN_MAINSESSION:
7197 /* stdin need not receive an unthrottle
7198 * notification since it will be polled */
7199 break;
7200 case CHAN_X11:
7201 x11_unthrottle(c->u.x11.s);
7202 break;
7203 case CHAN_AGENT:
7204 /* agent sockets are request/response and need no
7205 * buffer management */
7206 break;
7207 case CHAN_SOCKDATA:
7208 pfd_unthrottle(c->u.pfd.s);
7209 break;
7210 }
7211 }
7212 }
7cca0d81 7213 }
e5574168 7214 }
7215
7216 crFinishV;
7217}
7218
7219/*
b09eaa88 7220 * Handlers for SSH2 messages that might arrive at any moment.
7221 */
7222void ssh2_msg_disconnect(Ssh ssh, struct Packet *pktin)
7223{
7224 /* log reason code in disconnect message */
7225 char *buf, *msg;
7226 int nowlen, reason, msglen;
7227
7228 reason = ssh_pkt_getuint32(pktin);
7229 ssh_pkt_getstring(pktin, &msg, &msglen);
7230
7231 if (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) {
7232 buf = dupprintf("Received disconnect message (%s)",
7233 ssh2_disconnect_reasons[reason]);
7234 } else {
7235 buf = dupprintf("Received disconnect message (unknown"
7236 " type %d)", reason);
7237 }
7238 logevent(buf);
7239 sfree(buf);
7240 buf = dupprintf("Disconnection message text: %n%.*s",
7241 &nowlen, msglen, msg);
7242 logevent(buf);
7243 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
7244 reason,
7245 (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) ?
7246 ssh2_disconnect_reasons[reason] : "unknown",
7247 buf+nowlen));
7248 sfree(buf);
7249}
7250
7251void ssh2_msg_debug(Ssh ssh, struct Packet *pktin)
7252{
7253 /* log the debug message */
7254 char *buf, *msg;
7255 int msglen;
7256 int always_display;
7257
7258 /* XXX maybe we should actually take notice of this */
7259 always_display = ssh2_pkt_getbool(pktin);
7260 ssh_pkt_getstring(pktin, &msg, &msglen);
7261
7262 buf = dupprintf("Remote debug message: %.*s", msglen, msg);
7263 logevent(buf);
7264 sfree(buf);
7265}
7266
7267void ssh2_msg_something_unimplemented(Ssh ssh, struct Packet *pktin)
7268{
7269 struct Packet *pktout;
7270 pktout = ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED);
7271 ssh2_pkt_adduint32(pktout, pktin->sequence);
7272 /*
7273 * UNIMPLEMENTED messages MUST appear in the same order as the
7274 * messages they respond to. Hence, never queue them.
7275 */
7276 ssh2_pkt_send_noqueue(ssh, pktout);
7277}
7278
7279/*
7cca0d81 7280 * Handle the top-level SSH2 protocol.
7281 */
b09eaa88 7282static void ssh2_protocol_setup(Ssh ssh)
7283{
7284 int i;
7285
7286 /*
7287 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
7288 */
7289 for (i = 0; i < 256; i++)
7290 ssh->packet_dispatch[i] = ssh2_msg_something_unimplemented;
7291
7292 /*
7293 * Any message we actually understand, we set to NULL so that
7294 * the coroutines will get it.
7295 */
7296 ssh->packet_dispatch[SSH2_MSG_UNIMPLEMENTED] = NULL;
7297 ssh->packet_dispatch[SSH2_MSG_SERVICE_REQUEST] = NULL;
7298 ssh->packet_dispatch[SSH2_MSG_SERVICE_ACCEPT] = NULL;
7299 ssh->packet_dispatch[SSH2_MSG_KEXINIT] = NULL;
7300 ssh->packet_dispatch[SSH2_MSG_NEWKEYS] = NULL;
7301 ssh->packet_dispatch[SSH2_MSG_KEXDH_INIT] = NULL;
7302 ssh->packet_dispatch[SSH2_MSG_KEXDH_REPLY] = NULL;
7303 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
7304 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
7305 ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_INIT] = NULL;
7306 ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REPLY] = NULL;
7307 ssh->packet_dispatch[SSH2_MSG_USERAUTH_REQUEST] = NULL;
7308 ssh->packet_dispatch[SSH2_MSG_USERAUTH_FAILURE] = NULL;
7309 ssh->packet_dispatch[SSH2_MSG_USERAUTH_SUCCESS] = NULL;
7310 ssh->packet_dispatch[SSH2_MSG_USERAUTH_BANNER] = NULL;
7311 ssh->packet_dispatch[SSH2_MSG_USERAUTH_PK_OK] = NULL;
7312 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
7313 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
7314 ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_RESPONSE] = NULL;
7315 ssh->packet_dispatch[SSH2_MSG_GLOBAL_REQUEST] = NULL;
7316 ssh->packet_dispatch[SSH2_MSG_REQUEST_SUCCESS] = NULL;
7317 ssh->packet_dispatch[SSH2_MSG_REQUEST_FAILURE] = NULL;
7318 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN] = NULL;
7319 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION] = NULL;
7320 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_FAILURE] = NULL;
7321 ssh->packet_dispatch[SSH2_MSG_CHANNEL_WINDOW_ADJUST] = NULL;
7322 ssh->packet_dispatch[SSH2_MSG_CHANNEL_DATA] = NULL;
7323 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EXTENDED_DATA] = NULL;
7324 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EOF] = NULL;
7325 ssh->packet_dispatch[SSH2_MSG_CHANNEL_CLOSE] = NULL;
7326 ssh->packet_dispatch[SSH2_MSG_CHANNEL_REQUEST] = NULL;
7327 ssh->packet_dispatch[SSH2_MSG_CHANNEL_SUCCESS] = NULL;
7328 ssh->packet_dispatch[SSH2_MSG_CHANNEL_FAILURE] = NULL;
7329
7330 /*
7331 * These special message types we install handlers for.
7332 */
7333 ssh->packet_dispatch[SSH2_MSG_DISCONNECT] = ssh2_msg_disconnect;
7334 ssh->packet_dispatch[SSH2_MSG_IGNORE] = ssh_msg_ignore; /* shared with ssh1 */
7335 ssh->packet_dispatch[SSH2_MSG_DEBUG] = ssh2_msg_debug;
7336}
7337
9442dd57 7338static void ssh2_timer(void *ctx, long now)
7339{
7340 Ssh ssh = (Ssh)ctx;
7341
e6c1536e 7342 if (!ssh->kex_in_progress && ssh->cfg.ssh_rekey_time != 0 &&
9442dd57 7343 now - ssh->next_rekey >= 0) {
f382c87d 7344 do_ssh2_transport(ssh, "timeout", -1, NULL);
9442dd57 7345 }
7346}
7347
ff3187f6 7348static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen,
7349 struct Packet *pktin)
7cca0d81 7350{
b09eaa88 7351 if (ssh->state == SSH_STATE_CLOSED)
7352 return;
7353
9442dd57 7354 if (pktin) {
7355 ssh->incoming_data_size += pktin->encrypted_len;
7356 if (!ssh->kex_in_progress &&
d57f70af 7357 ssh->max_data_size != 0 &&
7358 ssh->incoming_data_size > ssh->max_data_size)
f382c87d 7359 do_ssh2_transport(ssh, "too much data received", -1, NULL);
9442dd57 7360 }
7361
b09eaa88 7362 if (pktin && ssh->packet_dispatch[pktin->type]) {
7363 ssh->packet_dispatch[pktin->type](ssh, pktin);
32874aea 7364 return;
b09eaa88 7365 }
7366
7367 if (!ssh->protocol_initial_phase_done ||
7368 (pktin && pktin->type >= 20 && pktin->type < 50)) {
7369 if (do_ssh2_transport(ssh, in, inlen, pktin) &&
7370 !ssh->protocol_initial_phase_done) {
7371 ssh->protocol_initial_phase_done = TRUE;
7372 /*
7373 * Allow authconn to initialise itself.
7374 */
7375 do_ssh2_authconn(ssh, NULL, 0, NULL);
7376 }
7377 } else {
7378 do_ssh2_authconn(ssh, in, inlen, pktin);
7379 }
7cca0d81 7380}
7381
7382/*
8df7a775 7383 * Called to set up the connection.
374330e2 7384 *
7385 * Returns an error message, or NULL on success.
374330e2 7386 */
cbe2d68f 7387static const char *ssh_init(void *frontend_handle, void **backend_handle,
7388 Config *cfg,
79bf227b 7389 char *host, int port, char **realhost, int nodelay,
7390 int keepalive)
32874aea 7391{
cbe2d68f 7392 const char *p;
51470298 7393 Ssh ssh;
7394
3d88e64d 7395 ssh = snew(struct ssh_tag);
86916870 7396 ssh->cfg = *cfg; /* STRUCTURE COPY */
125105d1 7397 ssh->version = 0; /* when not ready yet */
51470298 7398 ssh->s = NULL;
7399 ssh->cipher = NULL;
371e569c 7400 ssh->v1_cipher_ctx = NULL;
0183b242 7401 ssh->crcda_ctx = NULL;
51470298 7402 ssh->cscipher = NULL;
371e569c 7403 ssh->cs_cipher_ctx = NULL;
51470298 7404 ssh->sccipher = NULL;
371e569c 7405 ssh->sc_cipher_ctx = NULL;
51470298 7406 ssh->csmac = NULL;
a8327734 7407 ssh->cs_mac_ctx = NULL;
51470298 7408 ssh->scmac = NULL;
e0e1a00d 7409 ssh->sc_mac_ctx = NULL;
51470298 7410 ssh->cscomp = NULL;
5366aed8 7411 ssh->cs_comp_ctx = NULL;
51470298 7412 ssh->sccomp = NULL;
5366aed8 7413 ssh->sc_comp_ctx = NULL;
51470298 7414 ssh->kex = NULL;
389aa499 7415 ssh->kex_ctx = NULL;
51470298 7416 ssh->hostkey = NULL;
7417 ssh->exitcode = -1;
ac934965 7418 ssh->close_expected = FALSE;
51470298 7419 ssh->state = SSH_STATE_PREPACKET;
7420 ssh->size_needed = FALSE;
7421 ssh->eof_needed = FALSE;
b9d7bcad 7422 ssh->ldisc = NULL;
a8327734 7423 ssh->logctx = NULL;
51470298 7424 ssh->deferred_send_data = NULL;
7425 ssh->deferred_len = 0;
7426 ssh->deferred_size = 0;
7427 ssh->fallback_cmd = 0;
7428 ssh->pkt_ctx = 0;
302121de 7429 ssh->x11auth = NULL;
be738459 7430 ssh->v1_compressing = FALSE;
51470298 7431 ssh->v2_outgoing_sequence = 0;
7432 ssh->ssh1_rdpkt_crstate = 0;
7433 ssh->ssh2_rdpkt_crstate = 0;
7434 ssh->do_ssh_init_crstate = 0;
7435 ssh->ssh_gotdata_crstate = 0;
b09eaa88 7436 ssh->do_ssh1_connection_crstate = 0;
51470298 7437 ssh->do_ssh1_login_crstate = 0;
7438 ssh->do_ssh2_transport_crstate = 0;
7439 ssh->do_ssh2_authconn_crstate = 0;
7440 ssh->do_ssh_init_state = NULL;
7441 ssh->do_ssh1_login_state = NULL;
7442 ssh->do_ssh2_transport_state = NULL;
7443 ssh->do_ssh2_authconn_state = NULL;
6571dbfd 7444 ssh->mainchan = NULL;
968d2d92 7445 ssh->throttled_all = 0;
7446 ssh->v1_stdout_throttling = 0;
590f6a5f 7447 ssh->queue = NULL;
7448 ssh->queuelen = ssh->queuesize = 0;
7449 ssh->queueing = FALSE;
06fadff5 7450 ssh->qhead = ssh->qtail = NULL;
e13bba36 7451 ssh->deferred_rekey_reason = NULL;
51470298 7452
7453 *backend_handle = ssh;
32874aea 7454
8f203108 7455#ifdef MSCRYPTOAPI
32874aea 7456 if (crypto_startup() == 0)
8f203108 7457 return "Microsoft high encryption pack not installed!";
7458#endif
374330e2 7459
51470298 7460 ssh->frontend = frontend_handle;
86916870 7461 ssh->term_width = ssh->cfg.width;
7462 ssh->term_height = ssh->cfg.height;
887035a5 7463
fabd1805 7464 ssh->channels = NULL;
7465 ssh->rportfwds = NULL;
f47a5ffb 7466 ssh->portfwds = NULL;
fabd1805 7467
51470298 7468 ssh->send_ok = 0;
7469 ssh->editing = 0;
7470 ssh->echoing = 0;
7471 ssh->v1_throttle_count = 0;
7472 ssh->overall_bufsize = 0;
7473 ssh->fallback_cmd = 0;
8df7a775 7474
3648d4c5 7475 ssh->protocol = NULL;
7476
b09eaa88 7477 ssh->protocol_initial_phase_done = FALSE;
7478
39934deb 7479 ssh->pinger = NULL;
7480
9442dd57 7481 ssh->incoming_data_size = ssh->outgoing_data_size =
7482 ssh->deferred_data_size = 0L;
d57f70af 7483 ssh->max_data_size = parse_blocksize(ssh->cfg.ssh_rekey_data);
9442dd57 7484 ssh->kex_in_progress = FALSE;
7485
79bf227b 7486 p = connect_to_host(ssh, host, port, realhost, nodelay, keepalive);
fb09bf1c 7487 if (p != NULL)
7488 return p;
374330e2 7489
5d17ccfc 7490 random_ref();
7491
374330e2 7492 return NULL;
7493}
7494
fabd1805 7495static void ssh_free(void *handle)
7496{
7497 Ssh ssh = (Ssh) handle;
7498 struct ssh_channel *c;
7499 struct ssh_rportfwd *pf;
7500
7501 if (ssh->v1_cipher_ctx)
7502 ssh->cipher->free_context(ssh->v1_cipher_ctx);
7503 if (ssh->cs_cipher_ctx)
7504 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
7505 if (ssh->sc_cipher_ctx)
7506 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
7507 if (ssh->cs_mac_ctx)
7508 ssh->csmac->free_context(ssh->cs_mac_ctx);
7509 if (ssh->sc_mac_ctx)
7510 ssh->scmac->free_context(ssh->sc_mac_ctx);
29b1d0b3 7511 if (ssh->cs_comp_ctx) {
7512 if (ssh->cscomp)
7513 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
7514 else
7515 zlib_compress_cleanup(ssh->cs_comp_ctx);
7516 }
7517 if (ssh->sc_comp_ctx) {
7518 if (ssh->sccomp)
7519 ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
7520 else
7521 zlib_decompress_cleanup(ssh->sc_comp_ctx);
7522 }
fabd1805 7523 if (ssh->kex_ctx)
7524 dh_cleanup(ssh->kex_ctx);
7525 sfree(ssh->savedhost);
7526
590f6a5f 7527 while (ssh->queuelen-- > 0)
7528 ssh_free_packet(ssh->queue[ssh->queuelen]);
7529 sfree(ssh->queue);
7530
06fadff5 7531 while (ssh->qhead) {
7532 struct queued_handler *qh = ssh->qhead;
7533 ssh->qhead = qh->next;
7534 sfree(ssh->qhead);
7535 }
7536 ssh->qhead = ssh->qtail = NULL;
7537
fabd1805 7538 if (ssh->channels) {
7539 while ((c = delpos234(ssh->channels, 0)) != NULL) {
7540 switch (c->type) {
7541 case CHAN_X11:
7542 if (c->u.x11.s != NULL)
7543 x11_close(c->u.x11.s);
7544 break;
7545 case CHAN_SOCKDATA:
7546 if (c->u.pfd.s != NULL)
7547 pfd_close(c->u.pfd.s);
7548 break;
7549 }
7550 sfree(c);
7551 }
7552 freetree234(ssh->channels);
cdb52705 7553 ssh->channels = NULL;
fabd1805 7554 }
7555
7556 if (ssh->rportfwds) {
7557 while ((pf = delpos234(ssh->rportfwds, 0)) != NULL)
7558 sfree(pf);
7559 freetree234(ssh->rportfwds);
cdb52705 7560 ssh->rportfwds = NULL;
fabd1805 7561 }
7562 sfree(ssh->deferred_send_data);
7563 if (ssh->x11auth)
7564 x11_free_auth(ssh->x11auth);
7565 sfree(ssh->do_ssh_init_state);
7566 sfree(ssh->do_ssh1_login_state);
7567 sfree(ssh->do_ssh2_transport_state);
7568 sfree(ssh->do_ssh2_authconn_state);
679539d7 7569 if (ssh->crcda_ctx) {
7570 crcda_free_context(ssh->crcda_ctx);
7571 ssh->crcda_ctx = NULL;
7572 }
fabd1805 7573 if (ssh->s)
ac934965 7574 ssh_do_close(ssh, TRUE);
9442dd57 7575 expire_timer_context(ssh);
39934deb 7576 if (ssh->pinger)
7577 pinger_free(ssh->pinger);
ee50e8b6 7578 sfree(ssh);
5d17ccfc 7579
7580 random_unref();
fabd1805 7581}
7582
374330e2 7583/*
86916870 7584 * Reconfigure the SSH backend.
86916870 7585 */
7586static void ssh_reconfig(void *handle, Config *cfg)
7587{
7588 Ssh ssh = (Ssh) handle;
e13bba36 7589 char *rekeying = NULL, rekey_mandatory = FALSE;
e6c1536e 7590 unsigned long old_max_data_size;
7591
39934deb 7592 pinger_reconfig(ssh->pinger, &ssh->cfg, cfg);
fda2feb1 7593 ssh_setup_portfwd(ssh, cfg);
e6c1536e 7594
7595 if (ssh->cfg.ssh_rekey_time != cfg->ssh_rekey_time &&
7596 cfg->ssh_rekey_time != 0) {
7597 long new_next = ssh->last_rekey + cfg->ssh_rekey_time*60*TICKSPERSEC;
7598 long now = GETTICKCOUNT();
7599
7600 if (new_next - now < 0) {
f382c87d 7601 rekeying = "timeout shortened";
e6c1536e 7602 } else {
7603 ssh->next_rekey = schedule_timer(new_next - now, ssh2_timer, ssh);
7604 }
7605 }
7606
7607 old_max_data_size = ssh->max_data_size;
7608 ssh->max_data_size = parse_blocksize(cfg->ssh_rekey_data);
7609 if (old_max_data_size != ssh->max_data_size &&
7610 ssh->max_data_size != 0) {
7611 if (ssh->outgoing_data_size > ssh->max_data_size ||
7612 ssh->incoming_data_size > ssh->max_data_size)
f382c87d 7613 rekeying = "data limit lowered";
e6c1536e 7614 }
7615
e13bba36 7616 if (ssh->cfg.compression != cfg->compression) {
f382c87d 7617 rekeying = "compression setting changed";
e13bba36 7618 rekey_mandatory = TRUE;
7619 }
7620
7621 if (ssh->cfg.ssh2_des_cbc != cfg->ssh2_des_cbc ||
7622 memcmp(ssh->cfg.ssh_cipherlist, cfg->ssh_cipherlist,
7623 sizeof(ssh->cfg.ssh_cipherlist))) {
f382c87d 7624 rekeying = "cipher settings changed";
e13bba36 7625 rekey_mandatory = TRUE;
e6c1536e 7626 }
7627
86916870 7628 ssh->cfg = *cfg; /* STRUCTURE COPY */
e13bba36 7629
7630 if (rekeying) {
7631 if (!ssh->kex_in_progress) {
7632 do_ssh2_transport(ssh, rekeying, -1, NULL);
7633 } else if (rekey_mandatory) {
7634 ssh->deferred_rekey_reason = rekeying;
7635 }
7636 }
86916870 7637}
7638
7639/*
374330e2 7640 * Called to send data down the Telnet connection.
7641 */
51470298 7642static int ssh_send(void *handle, char *buf, int len)
32874aea 7643{
51470298 7644 Ssh ssh = (Ssh) handle;
7645
7646 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
5471d09a 7647 return 0;
374330e2 7648
d8baa528 7649 ssh->protocol(ssh, (unsigned char *)buf, len, 0);
5471d09a 7650
51470298 7651 return ssh_sendbuffer(ssh);
5471d09a 7652}
7653
7654/*
7655 * Called to query the current amount of buffered stdin data.
7656 */
51470298 7657static int ssh_sendbuffer(void *handle)
5471d09a 7658{
51470298 7659 Ssh ssh = (Ssh) handle;
5471d09a 7660 int override_value;
7661
51470298 7662 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
5471d09a 7663 return 0;
7664
7665 /*
7666 * If the SSH socket itself has backed up, add the total backup
7667 * size on that to any individual buffer on the stdin channel.
7668 */
7669 override_value = 0;
51470298 7670 if (ssh->throttled_all)
7671 override_value = ssh->overall_bufsize;
5471d09a 7672
51470298 7673 if (ssh->version == 1) {
5471d09a 7674 return override_value;
51470298 7675 } else if (ssh->version == 2) {
7676 if (!ssh->mainchan || ssh->mainchan->closes > 0)
5471d09a 7677 return override_value;
7678 else
51470298 7679 return (override_value +
7680 bufchain_size(&ssh->mainchan->v.v2.outbuffer));
5471d09a 7681 }
7682
7683 return 0;
374330e2 7684}
7685
7686/*
6e48c3fe 7687 * Called to set the size of the window from SSH's POV.
374330e2 7688 */
51470298 7689static void ssh_size(void *handle, int width, int height)
32874aea 7690{
51470298 7691 Ssh ssh = (Ssh) handle;
ff3187f6 7692 struct Packet *pktout;
51470298 7693
7694 ssh->term_width = width;
7695 ssh->term_height = height;
f278d6f8 7696
51470298 7697 switch (ssh->state) {
374330e2 7698 case SSH_STATE_BEFORE_SIZE:
3687d221 7699 case SSH_STATE_PREPACKET:
21248260 7700 case SSH_STATE_CLOSED:
374330e2 7701 break; /* do nothing */
7702 case SSH_STATE_INTERMED:
51470298 7703 ssh->size_needed = TRUE; /* buffer for later */
374330e2 7704 break;
7705 case SSH_STATE_SESSION:
86916870 7706 if (!ssh->cfg.nopty) {
51470298 7707 if (ssh->version == 1) {
7708 send_packet(ssh, SSH1_CMSG_WINDOW_SIZE,
7709 PKT_INT, ssh->term_height,
7710 PKT_INT, ssh->term_width,
32874aea 7711 PKT_INT, 0, PKT_INT, 0, PKT_END);
0ed48730 7712 } else if (ssh->mainchan) {
ff3187f6 7713 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7714 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7715 ssh2_pkt_addstring(pktout, "window-change");
7716 ssh2_pkt_addbool(pktout, 0);
7717 ssh2_pkt_adduint32(pktout, ssh->term_width);
7718 ssh2_pkt_adduint32(pktout, ssh->term_height);
7719 ssh2_pkt_adduint32(pktout, 0);
7720 ssh2_pkt_adduint32(pktout, 0);
7721 ssh2_pkt_send(ssh, pktout);
32874aea 7722 }
7723 }
7724 break;
374330e2 7725 }
7726}
7727
7728/*
125105d1 7729 * Return a list of the special codes that make sense in this
7730 * protocol.
7731 */
7732static const struct telnet_special *ssh_get_specials(void *handle)
7733{
786ba75e 7734 static const struct telnet_special ssh1_ignore_special[] = {
7735 {"IGNORE message", TS_NOP}
7736 };
7737 static const struct telnet_special ssh2_transport_specials[] = {
62638676 7738 {"IGNORE message", TS_NOP},
9442dd57 7739 {"Repeat key exchange", TS_REKEY},
62638676 7740 };
7741 static const struct telnet_special ssh2_session_specials[] = {
6f2d0cde 7742 {NULL, TS_SEP},
7743 {"Break", TS_BRK},
786ba75e 7744 /* These are the signal names defined by draft-ietf-secsh-connect-23.
6f2d0cde 7745 * They include all the ISO C signals, but are a subset of the POSIX
7746 * required signals. */
7747 {"SIGINT (Interrupt)", TS_SIGINT},
7748 {"SIGTERM (Terminate)", TS_SIGTERM},
7749 {"SIGKILL (Kill)", TS_SIGKILL},
7750 {"SIGQUIT (Quit)", TS_SIGQUIT},
7751 {"SIGHUP (Hangup)", TS_SIGHUP},
7752 {"More signals", TS_SUBMENU},
7753 {"SIGABRT", TS_SIGABRT}, {"SIGALRM", TS_SIGALRM},
7754 {"SIGFPE", TS_SIGFPE}, {"SIGILL", TS_SIGILL},
7755 {"SIGPIPE", TS_SIGPIPE}, {"SIGSEGV", TS_SIGSEGV},
7756 {"SIGUSR1", TS_SIGUSR1}, {"SIGUSR2", TS_SIGUSR2},
7757 {NULL, TS_EXITMENU}
62638676 7758 };
7759 static const struct telnet_special specials_end[] = {
6f2d0cde 7760 {NULL, TS_EXITMENU}
62638676 7761 };
786ba75e 7762 /* XXX review this length for any changes: */
7763 static struct telnet_special ssh_specials[lenof(ssh2_transport_specials) +
62638676 7764 lenof(ssh2_session_specials) +
7765 lenof(specials_end)];
125105d1 7766 Ssh ssh = (Ssh) handle;
62638676 7767 int i = 0;
7768#define ADD_SPECIALS(name) \
7769 do { \
7770 assert((i + lenof(name)) <= lenof(ssh_specials)); \
7771 memcpy(&ssh_specials[i], name, sizeof name); \
7772 i += lenof(name); \
7773 } while(0)
125105d1 7774
7775 if (ssh->version == 1) {
62638676 7776 /* Don't bother offering IGNORE if we've decided the remote
7777 * won't cope with it, since we wouldn't bother sending it if
7778 * asked anyway. */
7779 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE))
786ba75e 7780 ADD_SPECIALS(ssh1_ignore_special);
125105d1 7781 } else if (ssh->version == 2) {
786ba75e 7782 ADD_SPECIALS(ssh2_transport_specials);
62638676 7783 if (ssh->mainchan)
7784 ADD_SPECIALS(ssh2_session_specials);
7785 } /* else we're not ready yet */
7786
7787 if (i) {
7788 ADD_SPECIALS(specials_end);
7789 return ssh_specials;
7790 } else {
125105d1 7791 return NULL;
62638676 7792 }
7793#undef ADD_SPECIALS
125105d1 7794}
7795
7796/*
6abbf9e3 7797 * Send Telnet special codes. TS_EOF is useful for `plink', so you
7798 * can send an EOF and collect resulting output (e.g. `plink
7799 * hostname sort').
374330e2 7800 */
51470298 7801static void ssh_special(void *handle, Telnet_Special code)
32874aea 7802{
51470298 7803 Ssh ssh = (Ssh) handle;
ff3187f6 7804 struct Packet *pktout;
51470298 7805
6abbf9e3 7806 if (code == TS_EOF) {
51470298 7807 if (ssh->state != SSH_STATE_SESSION) {
32874aea 7808 /*
7809 * Buffer the EOF in case we are pre-SESSION, so we can
7810 * send it as soon as we reach SESSION.
7811 */
7812 if (code == TS_EOF)
51470298 7813 ssh->eof_needed = TRUE;
32874aea 7814 return;
7815 }
51470298 7816 if (ssh->version == 1) {
7817 send_packet(ssh, SSH1_CMSG_EOF, PKT_END);
0ed48730 7818 } else if (ssh->mainchan) {
ff3187f6 7819 struct Packet *pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF);
7820 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7821 ssh2_pkt_send(ssh, pktout);
32874aea 7822 }
7823 logevent("Sent EOF message");
125105d1 7824 } else if (code == TS_PING || code == TS_NOP) {
51470298 7825 if (ssh->state == SSH_STATE_CLOSED
7826 || ssh->state == SSH_STATE_PREPACKET) return;
7827 if (ssh->version == 1) {
7828 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE))
7829 send_packet(ssh, SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
32874aea 7830 } else {
ff3187f6 7831 pktout = ssh2_pkt_init(SSH2_MSG_IGNORE);
7832 ssh2_pkt_addstring_start(pktout);
590f6a5f 7833 ssh2_pkt_send_noqueue(ssh, pktout);
32874aea 7834 }
9442dd57 7835 } else if (code == TS_REKEY) {
7836 if (!ssh->kex_in_progress && ssh->version == 2) {
f382c87d 7837 do_ssh2_transport(ssh, "at user request", -1, NULL);
9442dd57 7838 }
125105d1 7839 } else if (code == TS_BRK) {
7840 if (ssh->state == SSH_STATE_CLOSED
7841 || ssh->state == SSH_STATE_PREPACKET) return;
7842 if (ssh->version == 1) {
7843 logevent("Unable to send BREAK signal in SSH1");
0ed48730 7844 } else if (ssh->mainchan) {
ff3187f6 7845 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7846 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7847 ssh2_pkt_addstring(pktout, "break");
7848 ssh2_pkt_addbool(pktout, 0);
7849 ssh2_pkt_adduint32(pktout, 0); /* default break length */
7850 ssh2_pkt_send(ssh, pktout);
125105d1 7851 }
6abbf9e3 7852 } else {
6f2d0cde 7853 /* Is is a POSIX signal? */
7854 char *signame = NULL;
7855 if (code == TS_SIGABRT) signame = "ABRT";
7856 if (code == TS_SIGALRM) signame = "ALRM";
7857 if (code == TS_SIGFPE) signame = "FPE";
7858 if (code == TS_SIGHUP) signame = "HUP";
7859 if (code == TS_SIGILL) signame = "ILL";
7860 if (code == TS_SIGINT) signame = "INT";
7861 if (code == TS_SIGKILL) signame = "KILL";
7862 if (code == TS_SIGPIPE) signame = "PIPE";
7863 if (code == TS_SIGQUIT) signame = "QUIT";
7864 if (code == TS_SIGSEGV) signame = "SEGV";
7865 if (code == TS_SIGTERM) signame = "TERM";
7866 if (code == TS_SIGUSR1) signame = "USR1";
7867 if (code == TS_SIGUSR2) signame = "USR2";
7868 /* The SSH-2 protocol does in principle support arbitrary named
7869 * signals, including signame@domain, but we don't support those. */
7870 if (signame) {
7871 /* It's a signal. */
7872 if (ssh->version == 2 && ssh->mainchan) {
ff3187f6 7873 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7874 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7875 ssh2_pkt_addstring(pktout, "signal");
7876 ssh2_pkt_addbool(pktout, 0);
7877 ssh2_pkt_addstring(pktout, signame);
7878 ssh2_pkt_send(ssh, pktout);
6f2d0cde 7879 logeventf(ssh, "Sent signal SIG%s", signame);
7880 }
7881 } else {
7882 /* Never heard of it. Do nothing */
7883 }
6abbf9e3 7884 }
374330e2 7885}
7886
51470298 7887void *new_sock_channel(void *handle, Socket s)
d74d141c 7888{
51470298 7889 Ssh ssh = (Ssh) handle;
d74d141c 7890 struct ssh_channel *c;
3d88e64d 7891 c = snew(struct ssh_channel);
51470298 7892 c->ssh = ssh;
d74d141c 7893
7894 if (c) {
bc240b21 7895 c->remoteid = -1; /* to be set when open confirmed */
51470298 7896 c->localid = alloc_channel_id(ssh);
d74d141c 7897 c->closes = 0;
bc240b21 7898 c->type = CHAN_SOCKDATA_DORMANT;/* identify channel type */
d74d141c 7899 c->u.pfd.s = s;
013dd8c0 7900 bufchain_init(&c->v.v2.outbuffer);
51470298 7901 add234(ssh->channels, c);
d74d141c 7902 }
7903 return c;
7904}
7905
5471d09a 7906/*
7907 * This is called when stdout/stderr (the entity to which
7908 * from_backend sends data) manages to clear some backlog.
7909 */
ae9ae89f 7910static void ssh_unthrottle(void *handle, int bufsize)
5471d09a 7911{
51470298 7912 Ssh ssh = (Ssh) handle;
7913 if (ssh->version == 1) {
7914 if (ssh->v1_stdout_throttling && bufsize < SSH1_BUFFER_LIMIT) {
7915 ssh->v1_stdout_throttling = 0;
7916 ssh1_throttle(ssh, -1);
5471d09a 7917 }
7918 } else {
51470298 7919 if (ssh->mainchan && ssh->mainchan->closes == 0)
7920 ssh2_set_window(ssh->mainchan, OUR_V2_WINSIZE - bufsize);
5471d09a 7921 }
7922}
7923
6b78788a 7924void ssh_send_port_open(void *channel, char *hostname, int port, char *org)
d74d141c 7925{
7926 struct ssh_channel *c = (struct ssh_channel *)channel;
6b78788a 7927 Ssh ssh = c->ssh;
ff3187f6 7928 struct Packet *pktout;
d74d141c 7929
57356d63 7930 logeventf(ssh, "Opening forwarded connection to %s:%d", hostname, port);
d74d141c 7931
51470298 7932 if (ssh->version == 1) {
7933 send_packet(ssh, SSH1_MSG_PORT_OPEN,
bc240b21 7934 PKT_INT, c->localid,
7935 PKT_STR, hostname,
7936 PKT_INT, port,
31fb1866 7937 /* PKT_STR, <org:orgport>, */
bc240b21 7938 PKT_END);
7939 } else {
ff3187f6 7940 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
7941 ssh2_pkt_addstring(pktout, "direct-tcpip");
7942 ssh2_pkt_adduint32(pktout, c->localid);
5471d09a 7943 c->v.v2.locwindow = OUR_V2_WINSIZE;
ff3187f6 7944 ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);/* our window size */
954d5c5a 7945 ssh2_pkt_adduint32(pktout, OUR_V2_MAXPKT); /* our max pkt size */
ff3187f6 7946 ssh2_pkt_addstring(pktout, hostname);
7947 ssh2_pkt_adduint32(pktout, port);
bc240b21 7948 /*
7949 * We make up values for the originator data; partly it's
7950 * too much hassle to keep track, and partly I'm not
7951 * convinced the server should be told details like that
7952 * about my local network configuration.
7953 */
ff3187f6 7954 ssh2_pkt_addstring(pktout, "client-side-connection");
7955 ssh2_pkt_adduint32(pktout, 0);
7956 ssh2_pkt_send(ssh, pktout);
bc240b21 7957 }
d74d141c 7958}
7959
51470298 7960static Socket ssh_socket(void *handle)
32874aea 7961{
51470298 7962 Ssh ssh = (Ssh) handle;
7963 return ssh->s;
32874aea 7964}
8ccc75b0 7965
51470298 7966static int ssh_sendok(void *handle)
32874aea 7967{
51470298 7968 Ssh ssh = (Ssh) handle;
7969 return ssh->send_ok;
32874aea 7970}
fb09bf1c 7971
51470298 7972static int ssh_ldisc(void *handle, int option)
32874aea 7973{
51470298 7974 Ssh ssh = (Ssh) handle;
32874aea 7975 if (option == LD_ECHO)
51470298 7976 return ssh->echoing;
32874aea 7977 if (option == LD_EDIT)
51470298 7978 return ssh->editing;
0965bee0 7979 return FALSE;
7980}
7981
b9d7bcad 7982static void ssh_provide_ldisc(void *handle, void *ldisc)
7983{
7984 Ssh ssh = (Ssh) handle;
7985 ssh->ldisc = ldisc;
7986}
7987
a8327734 7988static void ssh_provide_logctx(void *handle, void *logctx)
7989{
7990 Ssh ssh = (Ssh) handle;
7991 ssh->logctx = logctx;
7992}
7993
51470298 7994static int ssh_return_exitcode(void *handle)
7995{
7996 Ssh ssh = (Ssh) handle;
3bb2f322 7997 if (ssh->s != NULL)
7998 return -1;
7999 else
8000 return (ssh->exitcode >= 0 ? ssh->exitcode : 0);
51470298 8001}
8002
8003/*
f89c3294 8004 * cfg_info for SSH is the currently running version of the
8005 * protocol. (1 for 1; 2 for 2; 0 for not-decided-yet.)
8006 */
8007static int ssh_cfg_info(void *handle)
8008{
8009 Ssh ssh = (Ssh) handle;
8010 return ssh->version;
8011}
8012
8013/*
51470298 8014 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
8015 * that fails. This variable is the means by which scp.c can reach
8016 * into the SSH code and find out which one it got.
8017 */
8018extern int ssh_fallback_cmd(void *handle)
d8d6c7e5 8019{
51470298 8020 Ssh ssh = (Ssh) handle;
8021 return ssh->fallback_cmd;
d8d6c7e5 8022}
8023
374330e2 8024Backend ssh_backend = {
8025 ssh_init,
fabd1805 8026 ssh_free,
86916870 8027 ssh_reconfig,
374330e2 8028 ssh_send,
5471d09a 8029 ssh_sendbuffer,
374330e2 8030 ssh_size,
4017be6d 8031 ssh_special,
125105d1 8032 ssh_get_specials,
8ccc75b0 8033 ssh_socket,
d8d6c7e5 8034 ssh_return_exitcode,
97db3be4 8035 ssh_sendok,
0965bee0 8036 ssh_ldisc,
b9d7bcad 8037 ssh_provide_ldisc,
a8327734 8038 ssh_provide_logctx,
5471d09a 8039 ssh_unthrottle,
f89c3294 8040 ssh_cfg_info,
97db3be4 8041 22
bc240b21 8042};
Local modifications for Simon Tatham's `PuTTY' SSH client and terminal emulator