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[u/mdw/putty] / ssh.c
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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
d74d141c 363
85cc02bb 364const static struct ssh_signkey *hostkey_algs[] = { &ssh_rsa, &ssh_dss };
e5574168 365
e0e1a00d 366static void *nullmac_make_context(void)
367{
368 return NULL;
369}
370static void nullmac_free_context(void *handle)
371{
372}
373static void nullmac_key(void *handle, unsigned char *key)
32874aea 374{
375}
e0e1a00d 376static void nullmac_generate(void *handle, unsigned char *blk, int len,
32874aea 377 unsigned long seq)
378{
379}
e0e1a00d 380static int nullmac_verify(void *handle, unsigned char *blk, int len,
381 unsigned long seq)
32874aea 382{
383 return 1;
384}
57476f6b 385const static struct ssh_mac ssh_mac_none = {
e0e1a00d 386 nullmac_make_context, nullmac_free_context, nullmac_key,
387 nullmac_generate, nullmac_verify, "none", 0
e5574168 388};
8b2715b2 389const static struct ssh_mac *macs[] = {
32874aea 390 &ssh_sha1, &ssh_md5, &ssh_mac_none
391};
8b2715b2 392const static struct ssh_mac *buggymacs[] = {
32874aea 393 &ssh_sha1_buggy, &ssh_md5, &ssh_mac_none
394};
e5574168 395
5366aed8 396static void *ssh_comp_none_init(void)
397{
398 return NULL;
399}
400static void ssh_comp_none_cleanup(void *handle)
32874aea 401{
402}
5366aed8 403static int ssh_comp_none_block(void *handle, unsigned char *block, int len,
32874aea 404 unsigned char **outblock, int *outlen)
405{
406 return 0;
407}
5366aed8 408static int ssh_comp_none_disable(void *handle)
32874aea 409{
4ba9b64b 410 return 0;
411}
57476f6b 412const static struct ssh_compress ssh_comp_none = {
4ba9b64b 413 "none",
5366aed8 414 ssh_comp_none_init, ssh_comp_none_cleanup, ssh_comp_none_block,
415 ssh_comp_none_init, ssh_comp_none_cleanup, ssh_comp_none_block,
416 ssh_comp_none_disable, NULL
e5574168 417};
4ba9b64b 418extern const struct ssh_compress ssh_zlib;
419const static struct ssh_compress *compressions[] = {
32874aea 420 &ssh_zlib, &ssh_comp_none
421};
374330e2 422
32874aea 423enum { /* channel types */
783415f8 424 CHAN_MAINSESSION,
425 CHAN_X11,
426 CHAN_AGENT,
bc240b21 427 CHAN_SOCKDATA,
428 CHAN_SOCKDATA_DORMANT /* one the remote hasn't confirmed */
783415f8 429};
430
dacbd0e8 431/*
432 * 2-3-4 tree storing channels.
433 */
434struct ssh_channel {
51470298 435 Ssh ssh; /* pointer back to main context */
d211621f 436 unsigned remoteid, localid;
dacbd0e8 437 int type;
0357890f 438 /*
439 * In SSH1, this value contains four bits:
440 *
441 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
442 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
443 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
444 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
445 *
446 * A channel is completely finished with when all four bits are set.
447 */
dacbd0e8 448 int closes;
5471d09a 449 union {
450 struct ssh1_data_channel {
451 int throttling;
452 } v1;
453 struct ssh2_data_channel {
454 bufchain outbuffer;
455 unsigned remwindow, remmaxpkt;
456 unsigned locwindow;
457 } v2;
458 } v;
dacbd0e8 459 union {
32874aea 460 struct ssh_agent_channel {
461 unsigned char *message;
462 unsigned char msglen[4];
a03c9f9c 463 unsigned lensofar, totallen;
32874aea 464 } a;
465 struct ssh_x11_channel {
466 Socket s;
467 } x11;
d74d141c 468 struct ssh_pfd_channel {
469 Socket s;
470 } pfd;
dacbd0e8 471 } u;
472};
57476f6b 473
d74d141c 474/*
bc240b21 475 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
476 * 2 use this structure in different ways, reflecting SSH 2's
477 * altogether saner approach to port forwarding.
478 *
479 * In SSH 1, you arrange a remote forwarding by sending the server
480 * the remote port number, and the local destination host:port.
481 * When a connection comes in, the server sends you back that
482 * host:port pair, and you connect to it. This is a ready-made
483 * security hole if you're not on the ball: a malicious server
484 * could send you back _any_ host:port pair, so if you trustingly
485 * connect to the address it gives you then you've just opened the
486 * entire inside of your corporate network just by connecting
487 * through it to a dodgy SSH server. Hence, we must store a list of
488 * host:port pairs we _are_ trying to forward to, and reject a
489 * connection request from the server if it's not in the list.
490 *
491 * In SSH 2, each side of the connection minds its own business and
492 * doesn't send unnecessary information to the other. You arrange a
493 * remote forwarding by sending the server just the remote port
494 * number. When a connection comes in, the server tells you which
495 * of its ports was connected to; and _you_ have to remember what
496 * local host:port pair went with that port number.
497 *
06fadff5 498 * Hence, in SSH 1 this structure is indexed by destination
499 * host:port pair, whereas in SSH 2 it is indexed by source port.
d74d141c 500 */
fda2feb1 501struct ssh_portfwd; /* forward declaration */
502
d74d141c 503struct ssh_rportfwd {
bc240b21 504 unsigned sport, dport;
505 char dhost[256];
06fadff5 506 char *sportdesc;
fda2feb1 507 struct ssh_portfwd *pfrec;
d74d141c 508};
fda2feb1 509#define free_rportfwd(pf) ( \
510 ((pf) ? (sfree((pf)->sportdesc)) : (void)0 ), sfree(pf) )
511
512/*
513 * Separately to the rportfwd tree (which is for looking up port
514 * open requests from the server), a tree of _these_ structures is
515 * used to keep track of all the currently open port forwardings,
516 * so that we can reconfigure in mid-session if the user requests
517 * it.
518 */
519struct ssh_portfwd {
84328ddb 520 enum { DESTROY, KEEP, CREATE } status;
fda2feb1 521 int type;
522 unsigned sport, dport;
523 char *saddr, *daddr;
3fe92132 524 char *sserv, *dserv;
fda2feb1 525 struct ssh_rportfwd *remote;
05581745 526 int addressfamily;
fda2feb1 527 void *local;
528};
529#define free_portfwd(pf) ( \
3fe92132 530 ((pf) ? (sfree((pf)->saddr), sfree((pf)->daddr), \
531 sfree((pf)->sserv), sfree((pf)->dserv)) : (void)0 ), sfree(pf) )
d74d141c 532
57476f6b 533struct Packet {
534 long length;
535 int type;
b09eaa88 536 unsigned long sequence;
57476f6b 537 unsigned char *data;
538 unsigned char *body;
539 long savedpos;
540 long maxlen;
9442dd57 541 long encrypted_len; /* for SSH2 total-size counting */
ff3187f6 542
543 /*
544 * State associated with packet logging
545 */
546 int logmode;
547 int nblanks;
548 struct logblank_t *blanks;
57476f6b 549};
550
ff3187f6 551static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen,
552 struct Packet *pktin);
553static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen,
554 struct Packet *pktin);
b09eaa88 555static void ssh1_protocol_setup(Ssh ssh);
556static void ssh2_protocol_setup(Ssh ssh);
51470298 557static void ssh_size(void *handle, int width, int height);
558static void ssh_special(void *handle, Telnet_Special);
5471d09a 559static int ssh2_try_send(struct ssh_channel *c);
51470298 560static void ssh2_add_channel_data(struct ssh_channel *c, char *buf, int len);
561static void ssh_throttle_all(Ssh ssh, int enable, int bufsize);
5471d09a 562static void ssh2_set_window(struct ssh_channel *c, unsigned newwin);
51470298 563static int ssh_sendbuffer(void *handle);
36f94d1f 564static void ssh_do_close(Ssh ssh);
ff3187f6 565static unsigned long ssh_pkt_getuint32(struct Packet *pkt);
566static int ssh2_pkt_getbool(struct Packet *pkt);
567static void ssh_pkt_getstring(struct Packet *pkt, char **p, int *length);
9442dd57 568static void ssh2_timer(void *ctx, long now);
569static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen,
570 struct Packet *pktin);
57476f6b 571
51470298 572struct rdpkt1_state_tag {
57476f6b 573 long len, pad, biglen, to_read;
574 unsigned long realcrc, gotcrc;
575 unsigned char *p;
576 int i;
577 int chunk;
ff3187f6 578 struct Packet *pktin;
51470298 579};
57476f6b 580
51470298 581struct rdpkt2_state_tag {
960e736a 582 long len, pad, payload, packetlen, maclen;
583 int i;
584 int cipherblk;
585 unsigned long incoming_sequence;
ff3187f6 586 struct Packet *pktin;
51470298 587};
588
b09eaa88 589typedef void (*handler_fn_t)(Ssh ssh, struct Packet *pktin);
06fadff5 590typedef void (*chandler_fn_t)(Ssh ssh, struct Packet *pktin, void *ctx);
591
592struct queued_handler;
593struct queued_handler {
594 int msg1, msg2;
595 chandler_fn_t handler;
596 void *ctx;
597 struct queued_handler *next;
598};
b09eaa88 599
51470298 600struct ssh_tag {
601 const struct plug_function_table *fn;
602 /* the above field _must_ be first in the structure */
603
604 SHA_State exhash, exhashbase;
605
606 Socket s;
607
b9d7bcad 608 void *ldisc;
a8327734 609 void *logctx;
b9d7bcad 610
51470298 611 unsigned char session_key[32];
612 int v1_compressing;
613 int v1_remote_protoflags;
614 int v1_local_protoflags;
615 int agentfwd_enabled;
616 int X11_fwd_enabled;
617 int remote_bugs;
618 const struct ssh_cipher *cipher;
371e569c 619 void *v1_cipher_ctx;
0183b242 620 void *crcda_ctx;
51470298 621 const struct ssh2_cipher *cscipher, *sccipher;
371e569c 622 void *cs_cipher_ctx, *sc_cipher_ctx;
51470298 623 const struct ssh_mac *csmac, *scmac;
e0e1a00d 624 void *cs_mac_ctx, *sc_mac_ctx;
51470298 625 const struct ssh_compress *cscomp, *sccomp;
5366aed8 626 void *cs_comp_ctx, *sc_comp_ctx;
51470298 627 const struct ssh_kex *kex;
628 const struct ssh_signkey *hostkey;
629 unsigned char v2_session_id[20];
27cd7fc2 630 void *kex_ctx;
51470298 631
632 char *savedhost;
633 int savedport;
634 int send_ok;
635 int echoing, editing;
636
637 void *frontend;
638
db219738 639 int ospeed, ispeed; /* temporaries */
51470298 640 int term_width, term_height;
641
642 tree234 *channels; /* indexed by local id */
643 struct ssh_channel *mainchan; /* primary session channel */
644 int exitcode;
645
fda2feb1 646 tree234 *rportfwds, *portfwds;
51470298 647
648 enum {
649 SSH_STATE_PREPACKET,
650 SSH_STATE_BEFORE_SIZE,
651 SSH_STATE_INTERMED,
652 SSH_STATE_SESSION,
653 SSH_STATE_CLOSED
654 } state;
655
656 int size_needed, eof_needed;
657
590f6a5f 658 struct Packet **queue;
659 int queuelen, queuesize;
660 int queueing;
51470298 661 unsigned char *deferred_send_data;
662 int deferred_len, deferred_size;
663
664 /*
665 * Gross hack: pscp will try to start SFTP but fall back to
666 * scp1 if that fails. This variable is the means by which
667 * scp.c can reach into the SSH code and find out which one it
668 * got.
669 */
670 int fallback_cmd;
671
672 /*
673 * Used for username and password input.
674 */
675 char *userpass_input_buffer;
676 int userpass_input_buflen;
677 int userpass_input_bufpos;
678 int userpass_input_echo;
679
51470298 680 int pkt_ctx;
681
302121de 682 void *x11auth;
683
51470298 684 int version;
685 int v1_throttle_count;
686 int overall_bufsize;
687 int throttled_all;
688 int v1_stdout_throttling;
689 int v2_outgoing_sequence;
690
691 int ssh1_rdpkt_crstate;
692 int ssh2_rdpkt_crstate;
693 int do_ssh_init_crstate;
694 int ssh_gotdata_crstate;
51470298 695 int do_ssh1_login_crstate;
b09eaa88 696 int do_ssh1_connection_crstate;
51470298 697 int do_ssh2_transport_crstate;
698 int do_ssh2_authconn_crstate;
699
700 void *do_ssh_init_state;
701 void *do_ssh1_login_state;
702 void *do_ssh2_transport_state;
703 void *do_ssh2_authconn_state;
704
705 struct rdpkt1_state_tag rdpkt1_state;
706 struct rdpkt2_state_tag rdpkt2_state;
707
b09eaa88 708 /* ssh1 and ssh2 use this for different things, but both use it */
709 int protocol_initial_phase_done;
710
ff3187f6 711 void (*protocol) (Ssh ssh, unsigned char *in, int inlen,
712 struct Packet *pkt);
713 struct Packet *(*s_rdpkt) (Ssh ssh, unsigned char **data, int *datalen);
86916870 714
715 /*
716 * We maintain a full _copy_ of a Config structure here, not
717 * merely a pointer to it. That way, when we're passed a new
718 * one for reconfiguration, we can check the differences and
719 * potentially reconfigure port forwardings etc in mid-session.
720 */
721 Config cfg;
839f10db 722
723 /*
724 * Used to transfer data back from async agent callbacks.
725 */
726 void *agent_response;
727 int agent_response_len;
b09eaa88 728
729 /*
730 * Dispatch table for packet types that we may have to deal
731 * with at any time.
732 */
733 handler_fn_t packet_dispatch[256];
39934deb 734
735 /*
06fadff5 736 * Queues of one-off handler functions for success/failure
737 * indications from a request.
738 */
739 struct queued_handler *qhead, *qtail;
740
741 /*
39934deb 742 * This module deals with sending keepalives.
743 */
744 Pinger pinger;
9442dd57 745
746 /*
747 * Track incoming and outgoing data sizes and time, for
748 * size-based rekeys.
749 */
750 unsigned long incoming_data_size, outgoing_data_size, deferred_data_size;
d57f70af 751 unsigned long max_data_size;
9442dd57 752 int kex_in_progress;
e6c1536e 753 long next_rekey, last_rekey;
e13bba36 754 char *deferred_rekey_reason; /* points to STATIC string; don't free */
51470298 755};
960e736a 756
382908ad 757#define logevent(s) logevent(ssh->frontend, s)
a8327734 758
759/* logevent, only printf-formatted. */
cbe2d68f 760static void logeventf(Ssh ssh, const char *fmt, ...)
a8327734 761{
762 va_list ap;
57356d63 763 char *buf;
a8327734 764
765 va_start(ap, fmt);
57356d63 766 buf = dupvprintf(fmt, ap);
a8327734 767 va_end(ap);
57356d63 768 logevent(buf);
57356d63 769 sfree(buf);
a8327734 770}
771
6b5cf8b4 772#define bombout(msg) \
773 do { \
774 char *text = dupprintf msg; \
36f94d1f 775 ssh_do_close(ssh); \
6b5cf8b4 776 logevent(text); \
777 connection_fatal(ssh->frontend, "%s", text); \
778 sfree(text); \
779 } while (0)
a8327734 780
9a10ecf4 781/* Functions to leave bits out of the SSH packet log file. */
782
ff3187f6 783static void dont_log_password(Ssh ssh, struct Packet *pkt, int blanktype)
9a10ecf4 784{
785 if (ssh->cfg.logomitpass)
ff3187f6 786 pkt->logmode = blanktype;
9a10ecf4 787}
788
ff3187f6 789static void dont_log_data(Ssh ssh, struct Packet *pkt, int blanktype)
9a10ecf4 790{
791 if (ssh->cfg.logomitdata)
ff3187f6 792 pkt->logmode = blanktype;
9a10ecf4 793}
794
ff3187f6 795static void end_log_omission(Ssh ssh, struct Packet *pkt)
9a10ecf4 796{
ff3187f6 797 pkt->logmode = PKTLOG_EMIT;
9a10ecf4 798}
799
32874aea 800static int ssh_channelcmp(void *av, void *bv)
801{
802 struct ssh_channel *a = (struct ssh_channel *) av;
803 struct ssh_channel *b = (struct ssh_channel *) bv;
804 if (a->localid < b->localid)
805 return -1;
806 if (a->localid > b->localid)
807 return +1;
dacbd0e8 808 return 0;
809}
32874aea 810static int ssh_channelfind(void *av, void *bv)
811{
812 unsigned *a = (unsigned *) av;
813 struct ssh_channel *b = (struct ssh_channel *) bv;
814 if (*a < b->localid)
815 return -1;
816 if (*a > b->localid)
817 return +1;
dacbd0e8 818 return 0;
819}
820
bc240b21 821static int ssh_rportcmp_ssh1(void *av, void *bv)
d74d141c 822{
823 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
824 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
825 int i;
bc240b21 826 if ( (i = strcmp(a->dhost, b->dhost)) != 0)
d74d141c 827 return i < 0 ? -1 : +1;
bc240b21 828 if (a->dport > b->dport)
829 return +1;
830 if (a->dport < b->dport)
831 return -1;
832 return 0;
833}
834
835static int ssh_rportcmp_ssh2(void *av, void *bv)
836{
837 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
838 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
cdcbdf3b 839
bc240b21 840 if (a->sport > b->sport)
d74d141c 841 return +1;
bc240b21 842 if (a->sport < b->sport)
843 return -1;
d74d141c 844 return 0;
845}
846
fda2feb1 847/*
848 * Special form of strcmp which can cope with NULL inputs. NULL is
849 * defined to sort before even the empty string.
850 */
851static int nullstrcmp(const char *a, const char *b)
852{
853 if (a == NULL && b == NULL)
854 return 0;
855 if (a == NULL)
856 return -1;
857 if (b == NULL)
858 return +1;
859 return strcmp(a, b);
860}
861
862static int ssh_portcmp(void *av, void *bv)
863{
864 struct ssh_portfwd *a = (struct ssh_portfwd *) av;
865 struct ssh_portfwd *b = (struct ssh_portfwd *) bv;
866 int i;
867 if (a->type > b->type)
868 return +1;
869 if (a->type < b->type)
870 return -1;
84328ddb 871 if (a->addressfamily > b->addressfamily)
872 return +1;
873 if (a->addressfamily < b->addressfamily)
874 return -1;
fda2feb1 875 if ( (i = nullstrcmp(a->saddr, b->saddr)) != 0)
876 return i < 0 ? -1 : +1;
877 if (a->sport > b->sport)
878 return +1;
879 if (a->sport < b->sport)
880 return -1;
881 if (a->type != 'D') {
882 if ( (i = nullstrcmp(a->daddr, b->daddr)) != 0)
883 return i < 0 ? -1 : +1;
884 if (a->dport > b->dport)
885 return +1;
886 if (a->dport < b->dport)
887 return -1;
888 }
889 return 0;
890}
891
51470298 892static int alloc_channel_id(Ssh ssh)
32874aea 893{
260f3dec 894 const unsigned CHANNEL_NUMBER_OFFSET = 256;
895 unsigned low, high, mid;
d2371c81 896 int tsize;
897 struct ssh_channel *c;
898
899 /*
900 * First-fit allocation of channel numbers: always pick the
901 * lowest unused one. To do this, binary-search using the
902 * counted B-tree to find the largest channel ID which is in a
903 * contiguous sequence from the beginning. (Precisely
904 * everything in that sequence must have ID equal to its tree
905 * index plus CHANNEL_NUMBER_OFFSET.)
906 */
51470298 907 tsize = count234(ssh->channels);
d2371c81 908
32874aea 909 low = -1;
910 high = tsize;
d2371c81 911 while (high - low > 1) {
912 mid = (high + low) / 2;
51470298 913 c = index234(ssh->channels, mid);
d2371c81 914 if (c->localid == mid + CHANNEL_NUMBER_OFFSET)
915 low = mid; /* this one is fine */
916 else
917 high = mid; /* this one is past it */
918 }
919 /*
920 * Now low points to either -1, or the tree index of the
921 * largest ID in the initial sequence.
922 */
923 {
924 unsigned i = low + 1 + CHANNEL_NUMBER_OFFSET;
51470298 925 assert(NULL == find234(ssh->channels, &i, ssh_channelfind));
d2371c81 926 }
927 return low + 1 + CHANNEL_NUMBER_OFFSET;
928}
929
9fab77dc 930static void c_write(Ssh ssh, const char *buf, int len)
32874aea 931{
67779be7 932 if ((flags & FLAG_STDERR)) {
32874aea 933 int i;
934 for (i = 0; i < len; i++)
935 if (buf[i] != '\r')
936 fputc(buf[i], stderr);
fb09bf1c 937 return;
938 }
51470298 939 from_backend(ssh->frontend, 1, buf, len);
3bdaf79d 940}
941
9fab77dc 942static void c_write_untrusted(Ssh ssh, const char *buf, int len)
32874aea 943{
a209e957 944 int i;
945 for (i = 0; i < len; i++) {
32874aea 946 if (buf[i] == '\n')
51470298 947 c_write(ssh, "\r\n", 2);
32874aea 948 else if ((buf[i] & 0x60) || (buf[i] == '\r'))
51470298 949 c_write(ssh, buf + i, 1);
a209e957 950 }
951}
952
9fab77dc 953static void c_write_str(Ssh ssh, const char *buf)
32874aea 954{
51470298 955 c_write(ssh, buf, strlen(buf));
1408a877 956}
957
ff3187f6 958static void ssh_free_packet(struct Packet *pkt)
959{
960 sfree(pkt->data);
961 sfree(pkt);
962}
963static struct Packet *ssh_new_packet(void)
964{
965 struct Packet *pkt = snew(struct Packet);
966
967 pkt->data = NULL;
968 pkt->maxlen = 0;
969 pkt->logmode = PKTLOG_EMIT;
970 pkt->nblanks = 0;
971 pkt->blanks = NULL;
972
973 return pkt;
974}
975
fb09bf1c 976/*
977 * Collect incoming data in the incoming packet buffer.
e5574168 978 * Decipher and verify the packet when it is completely read.
979 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
fb09bf1c 980 * Update the *data and *datalen variables.
ff3187f6 981 * Return a Packet structure when a packet is completed.
fb09bf1c 982 */
ff3187f6 983static struct Packet *ssh1_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
fb09bf1c 984{
51470298 985 struct rdpkt1_state_tag *st = &ssh->rdpkt1_state;
374330e2 986
51470298 987 crBegin(ssh->ssh1_rdpkt_crstate);
374330e2 988
ff3187f6 989 st->pktin = ssh_new_packet();
990
991 st->pktin->type = 0;
992 st->pktin->length = 0;
374330e2 993
57476f6b 994 for (st->i = st->len = 0; st->i < 4; st->i++) {
fb09bf1c 995 while ((*datalen) == 0)
ff3187f6 996 crReturn(NULL);
57476f6b 997 st->len = (st->len << 8) + **data;
fb09bf1c 998 (*data)++, (*datalen)--;
999 }
374330e2 1000
57476f6b 1001 st->pad = 8 - (st->len % 8);
1002 st->biglen = st->len + st->pad;
ff3187f6 1003 st->pktin->length = st->len - 5;
fb09bf1c 1004
ae0500e5 1005 if (st->biglen < 0) {
1006 bombout(("Extremely large packet length from server suggests"
1007 " data stream corruption"));
ff3187f6 1008 ssh_free_packet(st->pktin);
1009 crStop(NULL);
ae0500e5 1010 }
1011
ff3187f6 1012 st->pktin->maxlen = st->biglen;
1013 st->pktin->data = snewn(st->biglen + APIEXTRA, unsigned char);
374330e2 1014
57476f6b 1015 st->to_read = st->biglen;
ff3187f6 1016 st->p = st->pktin->data;
57476f6b 1017 while (st->to_read > 0) {
32874aea 1018 st->chunk = st->to_read;
fb09bf1c 1019 while ((*datalen) == 0)
ff3187f6 1020 crReturn(NULL);
57476f6b 1021 if (st->chunk > (*datalen))
1022 st->chunk = (*datalen);
1023 memcpy(st->p, *data, st->chunk);
1024 *data += st->chunk;
1025 *datalen -= st->chunk;
1026 st->p += st->chunk;
1027 st->to_read -= st->chunk;
fb09bf1c 1028 }
374330e2 1029
ff3187f6 1030 if (ssh->cipher && detect_attack(ssh->crcda_ctx, st->pktin->data,
0183b242 1031 st->biglen, NULL)) {
6b5cf8b4 1032 bombout(("Network attack (CRC compensation) detected!"));
ff3187f6 1033 ssh_free_packet(st->pktin);
1034 crStop(NULL);
9a3a93a5 1035 }
1036
51470298 1037 if (ssh->cipher)
ff3187f6 1038 ssh->cipher->decrypt(ssh->v1_cipher_ctx, st->pktin->data, st->biglen);
374330e2 1039
ff3187f6 1040 st->realcrc = crc32_compute(st->pktin->data, st->biglen - 4);
1041 st->gotcrc = GET_32BIT(st->pktin->data + st->biglen - 4);
57476f6b 1042 if (st->gotcrc != st->realcrc) {
6b5cf8b4 1043 bombout(("Incorrect CRC received on packet"));
ff3187f6 1044 ssh_free_packet(st->pktin);
1045 crStop(NULL);
fb09bf1c 1046 }
572f871e 1047
ff3187f6 1048 st->pktin->body = st->pktin->data + st->pad + 1;
1049 st->pktin->savedpos = 0;
4ba9b64b 1050
51470298 1051 if (ssh->v1_compressing) {
4ba9b64b 1052 unsigned char *decompblk;
1053 int decomplen;
36b8d9bb 1054 if (!zlib_decompress_block(ssh->sc_comp_ctx,
ff3187f6 1055 st->pktin->body - 1, st->pktin->length + 1,
36b8d9bb 1056 &decompblk, &decomplen)) {
1057 bombout(("Zlib decompression encountered invalid data"));
ff3187f6 1058 ssh_free_packet(st->pktin);
1059 crStop(NULL);
36b8d9bb 1060 }
4ba9b64b 1061
ff3187f6 1062 if (st->pktin->maxlen < st->pad + decomplen) {
1063 st->pktin->maxlen = st->pad + decomplen;
1064 st->pktin->data = sresize(st->pktin->data,
1065 st->pktin->maxlen + APIEXTRA,
3d88e64d 1066 unsigned char);
ff3187f6 1067 st->pktin->body = st->pktin->data + st->pad + 1;
4ba9b64b 1068 }
1069
ff3187f6 1070 memcpy(st->pktin->body - 1, decompblk, decomplen);
dcbde236 1071 sfree(decompblk);
ff3187f6 1072 st->pktin->length = decomplen - 1;
4ba9b64b 1073 }
1074
ff3187f6 1075 st->pktin->type = st->pktin->body[-1];
00db133f 1076
9a10ecf4 1077 /*
1078 * Log incoming packet, possibly omitting sensitive fields.
1079 */
1080 if (ssh->logctx) {
1081 int nblanks = 0;
1082 struct logblank_t blank;
1083 if (ssh->cfg.logomitdata) {
1084 int do_blank = FALSE, blank_prefix = 0;
1085 /* "Session data" packets - omit the data field */
ff3187f6 1086 if ((st->pktin->type == SSH1_SMSG_STDOUT_DATA) ||
1087 (st->pktin->type == SSH1_SMSG_STDERR_DATA)) {
9a10ecf4 1088 do_blank = TRUE; blank_prefix = 0;
ff3187f6 1089 } else if (st->pktin->type == SSH1_MSG_CHANNEL_DATA) {
9a10ecf4 1090 do_blank = TRUE; blank_prefix = 4;
1091 }
1092 if (do_blank) {
1093 blank.offset = blank_prefix;
ff3187f6 1094 blank.len = st->pktin->length;
9a10ecf4 1095 blank.type = PKTLOG_OMIT;
1096 nblanks = 1;
1097 }
1098 }
a8327734 1099 log_packet(ssh->logctx,
ff3187f6 1100 PKT_INCOMING, st->pktin->type,
1101 ssh1_pkt_type(st->pktin->type),
1102 st->pktin->body, st->pktin->length,
9a10ecf4 1103 nblanks, &blank);
1104 }
00db133f 1105
ff3187f6 1106 crFinish(st->pktin);
fb09bf1c 1107}
1108
ff3187f6 1109static struct Packet *ssh2_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
e5574168 1110{
51470298 1111 struct rdpkt2_state_tag *st = &ssh->rdpkt2_state;
e5574168 1112
51470298 1113 crBegin(ssh->ssh2_rdpkt_crstate);
e5574168 1114
ff3187f6 1115 st->pktin = ssh_new_packet();
1116
1117 st->pktin->type = 0;
1118 st->pktin->length = 0;
51470298 1119 if (ssh->sccipher)
1120 st->cipherblk = ssh->sccipher->blksize;
e5574168 1121 else
32874aea 1122 st->cipherblk = 8;
960e736a 1123 if (st->cipherblk < 8)
32874aea 1124 st->cipherblk = 8;
960e736a 1125
ff3187f6 1126 st->pktin->data = snewn(st->cipherblk + APIEXTRA, unsigned char);
e5574168 1127
1128 /*
1129 * Acquire and decrypt the first block of the packet. This will
1130 * contain the length and padding details.
1131 */
32874aea 1132 for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) {
e5574168 1133 while ((*datalen) == 0)
ff3187f6 1134 crReturn(NULL);
1135 st->pktin->data[st->i] = *(*data)++;
32874aea 1136 (*datalen)--;
e5574168 1137 }
4252c9cc 1138
51470298 1139 if (ssh->sccipher)
371e569c 1140 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
ff3187f6 1141 st->pktin->data, st->cipherblk);
e5574168 1142
1143 /*
1144 * Now get the length and padding figures.
1145 */
ff3187f6 1146 st->len = GET_32BIT(st->pktin->data);
1147 st->pad = st->pktin->data[4];
e5574168 1148
1149 /*
717dc483 1150 * _Completely_ silly lengths should be stomped on before they
1151 * do us any more damage.
1152 */
1153 if (st->len < 0 || st->pad < 0 || st->len + st->pad < 0) {
6b5cf8b4 1154 bombout(("Incoming packet was garbled on decryption"));
ff3187f6 1155 ssh_free_packet(st->pktin);
1156 crStop(NULL);
717dc483 1157 }
1158
1159 /*
e5574168 1160 * This enables us to deduce the payload length.
1161 */
960e736a 1162 st->payload = st->len - st->pad - 1;
e5574168 1163
ff3187f6 1164 st->pktin->length = st->payload + 5;
e5574168 1165
1166 /*
1167 * So now we can work out the total packet length.
1168 */
960e736a 1169 st->packetlen = st->len + 4;
51470298 1170 st->maclen = ssh->scmac ? ssh->scmac->len : 0;
e5574168 1171
1172 /*
ff3187f6 1173 * Allocate memory for the rest of the packet.
e5574168 1174 */
ff3187f6 1175 st->pktin->maxlen = st->packetlen + st->maclen;
1176 st->pktin->data = sresize(st->pktin->data,
1177 st->pktin->maxlen + APIEXTRA,
1178 unsigned char);
e5574168 1179
1180 /*
1181 * Read and decrypt the remainder of the packet.
1182 */
32874aea 1183 for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen;
1184 st->i++) {
e5574168 1185 while ((*datalen) == 0)
ff3187f6 1186 crReturn(NULL);
1187 st->pktin->data[st->i] = *(*data)++;
32874aea 1188 (*datalen)--;
e5574168 1189 }
1190 /* Decrypt everything _except_ the MAC. */
51470298 1191 if (ssh->sccipher)
371e569c 1192 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
ff3187f6 1193 st->pktin->data + st->cipherblk,
51470298 1194 st->packetlen - st->cipherblk);
e5574168 1195
9442dd57 1196 st->pktin->encrypted_len = st->packetlen;
1197
e5574168 1198 /*
1199 * Check the MAC.
1200 */
51470298 1201 if (ssh->scmac
ff3187f6 1202 && !ssh->scmac->verify(ssh->sc_mac_ctx, st->pktin->data, st->len + 4,
51470298 1203 st->incoming_sequence)) {
6b5cf8b4 1204 bombout(("Incorrect MAC received on packet"));
ff3187f6 1205 ssh_free_packet(st->pktin);
1206 crStop(NULL);
8d5de777 1207 }
b09eaa88 1208
1209 st->pktin->sequence = st->incoming_sequence++;
e5574168 1210
4ba9b64b 1211 /*
1212 * Decompress packet payload.
1213 */
1214 {
1215 unsigned char *newpayload;
1216 int newlen;
51470298 1217 if (ssh->sccomp &&
5366aed8 1218 ssh->sccomp->decompress(ssh->sc_comp_ctx,
ff3187f6 1219 st->pktin->data + 5, st->pktin->length - 5,
51470298 1220 &newpayload, &newlen)) {
ff3187f6 1221 if (st->pktin->maxlen < newlen + 5) {
1222 st->pktin->maxlen = newlen + 5;
1223 st->pktin->data = sresize(st->pktin->data,
1224 st->pktin->maxlen + APIEXTRA,
3d88e64d 1225 unsigned char);
4ba9b64b 1226 }
ff3187f6 1227 st->pktin->length = 5 + newlen;
1228 memcpy(st->pktin->data + 5, newpayload, newlen);
dcbde236 1229 sfree(newpayload);
4ba9b64b 1230 }
1231 }
1232
ff3187f6 1233 st->pktin->savedpos = 6;
1234 st->pktin->body = st->pktin->data;
1235 st->pktin->type = st->pktin->data[5];
e5574168 1236
9a10ecf4 1237 /*
1238 * Log incoming packet, possibly omitting sensitive fields.
1239 */
1240 if (ssh->logctx) {
1241 int nblanks = 0;
1242 struct logblank_t blank;
1243 if (ssh->cfg.logomitdata) {
1244 int do_blank = FALSE, blank_prefix = 0;
1245 /* "Session data" packets - omit the data field */
ff3187f6 1246 if (st->pktin->type == SSH2_MSG_CHANNEL_DATA) {
9a10ecf4 1247 do_blank = TRUE; blank_prefix = 4;
ff3187f6 1248 } else if (st->pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
9a10ecf4 1249 do_blank = TRUE; blank_prefix = 8;
1250 }
1251 if (do_blank) {
1252 blank.offset = blank_prefix;
ff3187f6 1253 blank.len = (st->pktin->length-6) - blank_prefix;
9a10ecf4 1254 blank.type = PKTLOG_OMIT;
1255 nblanks = 1;
1256 }
1257 }
ff3187f6 1258 log_packet(ssh->logctx, PKT_INCOMING, st->pktin->type,
1259 ssh2_pkt_type(ssh->pkt_ctx, st->pktin->type),
1260 st->pktin->data+6, st->pktin->length-6,
9a10ecf4 1261 nblanks, &blank);
1262 }
00db133f 1263
ff3187f6 1264 crFinish(st->pktin);
e5574168 1265}
1266
ff3187f6 1267static void ssh1_pktout_size(struct Packet *pkt, int len)
32874aea 1268{
374330e2 1269 int pad, biglen;
1270
1271 len += 5; /* type and CRC */
32874aea 1272 pad = 8 - (len % 8);
374330e2 1273 biglen = len + pad;
1274
ff3187f6 1275 pkt->length = len - 5;
1276 if (pkt->maxlen < biglen) {
1277 pkt->maxlen = biglen;
1278 pkt->data = sresize(pkt->data, biglen + 4 + APIEXTRA, unsigned char);
374330e2 1279 }
ff3187f6 1280 pkt->body = pkt->data + 4 + pad + 1;
4ba9b64b 1281}
374330e2 1282
ff3187f6 1283static struct Packet *s_wrpkt_start(int type, int len)
32874aea 1284{
ff3187f6 1285 struct Packet *pkt = ssh_new_packet();
1286 ssh1_pktout_size(pkt, len);
1287 pkt->type = type;
9a10ecf4 1288 /* Initialise log omission state */
ff3187f6 1289 pkt->nblanks = 0;
1290 pkt->blanks = NULL;
1291 return pkt;
374330e2 1292}
1293
ff3187f6 1294static int s_wrpkt_prepare(Ssh ssh, struct Packet *pkt)
32874aea 1295{
fd7a4aad 1296 int pad, biglen, i;
374330e2 1297 unsigned long crc;
fd7a4aad 1298#ifdef __SC__
1299 /*
1300 * XXX various versions of SC (including 8.8.4) screw up the
1301 * register allocation in this function and use the same register
1302 * (D6) for len and as a temporary, with predictable results. The
1303 * following sledgehammer prevents this.
1304 */
1305 volatile
1306#endif
1307 int len;
374330e2 1308
ff3187f6 1309 pkt->body[-1] = pkt->type;
4ba9b64b 1310
a8327734 1311 if (ssh->logctx)
ff3187f6 1312 log_packet(ssh->logctx, PKT_OUTGOING, pkt->type,
1313 ssh1_pkt_type(pkt->type),
1314 pkt->body, pkt->length,
1315 pkt->nblanks, pkt->blanks);
1316 sfree(pkt->blanks); pkt->blanks = NULL;
1317 pkt->nblanks = 0;
00db133f 1318
51470298 1319 if (ssh->v1_compressing) {
4ba9b64b 1320 unsigned char *compblk;
1321 int complen;
5366aed8 1322 zlib_compress_block(ssh->cs_comp_ctx,
ff3187f6 1323 pkt->body - 1, pkt->length + 1,
4ba9b64b 1324 &compblk, &complen);
ff3187f6 1325 ssh1_pktout_size(pkt, complen - 1);
1326 memcpy(pkt->body - 1, compblk, complen);
dcbde236 1327 sfree(compblk);
4ba9b64b 1328 }
1329
ff3187f6 1330 len = pkt->length + 5; /* type and CRC */
32874aea 1331 pad = 8 - (len % 8);
374330e2 1332 biglen = len + pad;
1333
32874aea 1334 for (i = 0; i < pad; i++)
ff3187f6 1335 pkt->data[i + 4] = random_byte();
1336 crc = crc32_compute(pkt->data + 4, biglen - 4);
1337 PUT_32BIT(pkt->data + biglen, crc);
1338 PUT_32BIT(pkt->data, len);
374330e2 1339
51470298 1340 if (ssh->cipher)
ff3187f6 1341 ssh->cipher->encrypt(ssh->v1_cipher_ctx, pkt->data + 4, biglen);
374330e2 1342
32874aea 1343 return biglen + 4;
39065bed 1344}
1345
ff3187f6 1346static void s_wrpkt(Ssh ssh, struct Packet *pkt)
32874aea 1347{
5471d09a 1348 int len, backlog;
ff3187f6 1349 len = s_wrpkt_prepare(ssh, pkt);
1350 backlog = sk_write(ssh->s, (char *)pkt->data, len);
5471d09a 1351 if (backlog > SSH_MAX_BACKLOG)
51470298 1352 ssh_throttle_all(ssh, 1, backlog);
39065bed 1353}
1354
ff3187f6 1355static void s_wrpkt_defer(Ssh ssh, struct Packet *pkt)
32874aea 1356{
39065bed 1357 int len;
ff3187f6 1358 len = s_wrpkt_prepare(ssh, pkt);
51470298 1359 if (ssh->deferred_len + len > ssh->deferred_size) {
1360 ssh->deferred_size = ssh->deferred_len + len + 128;
3d88e64d 1361 ssh->deferred_send_data = sresize(ssh->deferred_send_data,
1362 ssh->deferred_size,
1363 unsigned char);
39065bed 1364 }
ff3187f6 1365 memcpy(ssh->deferred_send_data + ssh->deferred_len, pkt->data, len);
51470298 1366 ssh->deferred_len += len;
374330e2 1367}
1368
fb09bf1c 1369/*
39065bed 1370 * Construct a packet with the specified contents.
fb09bf1c 1371 */
ff3187f6 1372static struct Packet *construct_packet(Ssh ssh, int pkttype,
1373 va_list ap1, va_list ap2)
fb09bf1c 1374{
fb09bf1c 1375 unsigned char *p, *argp, argchar;
1376 unsigned long argint;
1377 int pktlen, argtype, arglen;
7cca0d81 1378 Bignum bn;
ff3187f6 1379 struct Packet *pkt;
fb09bf1c 1380
1381 pktlen = 0;
39065bed 1382 while ((argtype = va_arg(ap1, int)) != PKT_END) {
fb09bf1c 1383 switch (argtype) {
1384 case PKT_INT:
39065bed 1385 (void) va_arg(ap1, int);
fb09bf1c 1386 pktlen += 4;
1387 break;
1388 case PKT_CHAR:
1ec39246 1389 (void) va_arg(ap1, int);
fb09bf1c 1390 pktlen++;
1391 break;
1392 case PKT_DATA:
39065bed 1393 (void) va_arg(ap1, unsigned char *);
1394 arglen = va_arg(ap1, int);
fb09bf1c 1395 pktlen += arglen;
1396 break;
1397 case PKT_STR:
39065bed 1398 argp = va_arg(ap1, unsigned char *);
d8baa528 1399 arglen = strlen((char *)argp);
fb09bf1c 1400 pktlen += 4 + arglen;
1401 break;
7cca0d81 1402 case PKT_BIGNUM:
39065bed 1403 bn = va_arg(ap1, Bignum);
32874aea 1404 pktlen += ssh1_bignum_length(bn);
7cca0d81 1405 break;
9a10ecf4 1406 case PKTT_PASSWORD:
1407 case PKTT_DATA:
1408 case PKTT_OTHER:
1409 /* ignore this pass */
1410 break;
fb09bf1c 1411 default:
1412 assert(0);
1413 }
1414 }
fb09bf1c 1415
ff3187f6 1416 pkt = s_wrpkt_start(pkttype, pktlen);
1417 p = pkt->body;
fb09bf1c 1418
39065bed 1419 while ((argtype = va_arg(ap2, int)) != PKT_END) {
ff3187f6 1420 int offset = p - pkt->body, len = 0;
fb09bf1c 1421 switch (argtype) {
9a10ecf4 1422 /* Actual fields in the packet */
fb09bf1c 1423 case PKT_INT:
39065bed 1424 argint = va_arg(ap2, int);
fb09bf1c 1425 PUT_32BIT(p, argint);
9a10ecf4 1426 len = 4;
fb09bf1c 1427 break;
1428 case PKT_CHAR:
1ec39246 1429 argchar = (unsigned char) va_arg(ap2, int);
fb09bf1c 1430 *p = argchar;
9a10ecf4 1431 len = 1;
fb09bf1c 1432 break;
1433 case PKT_DATA:
39065bed 1434 argp = va_arg(ap2, unsigned char *);
1435 arglen = va_arg(ap2, int);
fb09bf1c 1436 memcpy(p, argp, arglen);
9a10ecf4 1437 len = arglen;
fb09bf1c 1438 break;
1439 case PKT_STR:
39065bed 1440 argp = va_arg(ap2, unsigned char *);
d8baa528 1441 arglen = strlen((char *)argp);
fb09bf1c 1442 PUT_32BIT(p, arglen);
1443 memcpy(p + 4, argp, arglen);
9a10ecf4 1444 len = arglen + 4;
fb09bf1c 1445 break;
7cca0d81 1446 case PKT_BIGNUM:
39065bed 1447 bn = va_arg(ap2, Bignum);
9a10ecf4 1448 len = ssh1_write_bignum(p, bn);
1449 break;
1450 /* Tokens for modifications to packet logging */
1451 case PKTT_PASSWORD:
ff3187f6 1452 dont_log_password(ssh, pkt, PKTLOG_BLANK);
9a10ecf4 1453 break;
1454 case PKTT_DATA:
ff3187f6 1455 dont_log_data(ssh, pkt, PKTLOG_OMIT);
7cca0d81 1456 break;
9a10ecf4 1457 case PKTT_OTHER:
ff3187f6 1458 end_log_omission(ssh, pkt);
9a10ecf4 1459 break;
1460 }
1461 p += len;
1462 /* Deal with logfile omission, if required. */
ff3187f6 1463 if (len && (pkt->logmode != PKTLOG_EMIT)) {
1464 pkt->nblanks++;
1465 pkt->blanks = sresize(pkt->blanks, pkt->nblanks,
1466 struct logblank_t);
1467 pkt->blanks[pkt->nblanks-1].offset = offset;
1468 pkt->blanks[pkt->nblanks-1].len = len;
1469 pkt->blanks[pkt->nblanks-1].type = pkt->logmode;
fb09bf1c 1470 }
1471 }
ff3187f6 1472
1473 return pkt;
39065bed 1474}
fb09bf1c 1475
51470298 1476static void send_packet(Ssh ssh, int pkttype, ...)
32874aea 1477{
ff3187f6 1478 struct Packet *pkt;
39065bed 1479 va_list ap1, ap2;
1480 va_start(ap1, pkttype);
1481 va_start(ap2, pkttype);
ff3187f6 1482 pkt = construct_packet(ssh, pkttype, ap1, ap2);
1483 va_end(ap2);
1484 va_end(ap1);
1485 s_wrpkt(ssh, pkt);
1486 ssh_free_packet(pkt);
fb09bf1c 1487}
1488
51470298 1489static void defer_packet(Ssh ssh, int pkttype, ...)
32874aea 1490{
ff3187f6 1491 struct Packet *pkt;
39065bed 1492 va_list ap1, ap2;
1493 va_start(ap1, pkttype);
1494 va_start(ap2, pkttype);
ff3187f6 1495 pkt = construct_packet(ssh, pkttype, ap1, ap2);
1496 va_end(ap2);
1497 va_end(ap1);
1498 s_wrpkt_defer(ssh, pkt);
1499 ssh_free_packet(pkt);
39065bed 1500}
1501
32874aea 1502static int ssh_versioncmp(char *a, char *b)
1503{
9697bfd2 1504 char *ae, *be;
1505 unsigned long av, bv;
1506
43aa02a7 1507 av = strtoul(a, &ae, 10);
1508 bv = strtoul(b, &be, 10);
32874aea 1509 if (av != bv)
1510 return (av < bv ? -1 : +1);
1511 if (*ae == '.')
1512 ae++;
1513 if (*be == '.')
1514 be++;
43aa02a7 1515 av = strtoul(ae, &ae, 10);
1516 bv = strtoul(be, &be, 10);
32874aea 1517 if (av != bv)
1518 return (av < bv ? -1 : +1);
9697bfd2 1519 return 0;
1520}
1521
e5574168 1522/*
a92dd380 1523 * Utility routines for putting an SSH-protocol `string' and
1524 * `uint32' into a SHA state.
e5574168 1525 */
1526#include <stdio.h>
32874aea 1527static void sha_string(SHA_State * s, void *str, int len)
1528{
e5574168 1529 unsigned char lenblk[4];
e5574168 1530 PUT_32BIT(lenblk, len);
e5574168 1531 SHA_Bytes(s, lenblk, 4);
e5574168 1532 SHA_Bytes(s, str, len);
1533}
1534
32874aea 1535static void sha_uint32(SHA_State * s, unsigned i)
1536{
a92dd380 1537 unsigned char intblk[4];
1538 PUT_32BIT(intblk, i);
1539 SHA_Bytes(s, intblk, 4);
1540}
1541
7cca0d81 1542/*
1543 * SSH2 packet construction functions.
1544 */
ff3187f6 1545static void ssh2_pkt_ensure(struct Packet *pkt, int length)
32874aea 1546{
ff3187f6 1547 if (pkt->maxlen < length) {
1548 pkt->maxlen = length + 256;
1549 pkt->data = sresize(pkt->data, pkt->maxlen + APIEXTRA, unsigned char);
7cca0d81 1550 }
783415f8 1551}
ff3187f6 1552static void ssh2_pkt_adddata(struct Packet *pkt, void *data, int len)
32874aea 1553{
ff3187f6 1554 if (pkt->logmode != PKTLOG_EMIT) {
1555 pkt->nblanks++;
1556 pkt->blanks = sresize(pkt->blanks, pkt->nblanks, struct logblank_t);
1557 pkt->blanks[pkt->nblanks-1].offset = pkt->length - 6;
1558 pkt->blanks[pkt->nblanks-1].len = len;
1559 pkt->blanks[pkt->nblanks-1].type = pkt->logmode;
1560 }
1561 pkt->length += len;
1562 ssh2_pkt_ensure(pkt, pkt->length);
1563 memcpy(pkt->data + pkt->length - len, data, len);
7cca0d81 1564}
ff3187f6 1565static void ssh2_pkt_addbyte(struct Packet *pkt, unsigned char byte)
32874aea 1566{
ff3187f6 1567 ssh2_pkt_adddata(pkt, &byte, 1);
7cca0d81 1568}
ff3187f6 1569static struct Packet *ssh2_pkt_init(int pkt_type)
32874aea 1570{
ff3187f6 1571 struct Packet *pkt = ssh_new_packet();
1572 pkt->length = 5;
1573 ssh2_pkt_addbyte(pkt, (unsigned char) pkt_type);
1574 return pkt;
7cca0d81 1575}
ff3187f6 1576static void ssh2_pkt_addbool(struct Packet *pkt, unsigned char value)
32874aea 1577{
ff3187f6 1578 ssh2_pkt_adddata(pkt, &value, 1);
7cca0d81 1579}
ff3187f6 1580static void ssh2_pkt_adduint32(struct Packet *pkt, unsigned long value)
32874aea 1581{
7cca0d81 1582 unsigned char x[4];
1583 PUT_32BIT(x, value);
ff3187f6 1584 ssh2_pkt_adddata(pkt, x, 4);
7cca0d81 1585}
ff3187f6 1586static void ssh2_pkt_addstring_start(struct Packet *pkt)
32874aea 1587{
ff3187f6 1588 ssh2_pkt_adduint32(pkt, 0);
1589 pkt->savedpos = pkt->length;
7cca0d81 1590}
ff3187f6 1591static void ssh2_pkt_addstring_str(struct Packet *pkt, char *data)
32874aea 1592{
ff3187f6 1593 ssh2_pkt_adddata(pkt, data, strlen(data));
1594 PUT_32BIT(pkt->data + pkt->savedpos - 4, pkt->length - pkt->savedpos);
7cca0d81 1595}
ff3187f6 1596static void ssh2_pkt_addstring_data(struct Packet *pkt, char *data, int len)
32874aea 1597{
ff3187f6 1598 ssh2_pkt_adddata(pkt, data, len);
1599 PUT_32BIT(pkt->data + pkt->savedpos - 4, pkt->length - pkt->savedpos);
7cca0d81 1600}
ff3187f6 1601static void ssh2_pkt_addstring(struct Packet *pkt, char *data)
32874aea 1602{
ff3187f6 1603 ssh2_pkt_addstring_start(pkt);
1604 ssh2_pkt_addstring_str(pkt, data);
7cca0d81 1605}
d8baa528 1606static unsigned char *ssh2_mpint_fmt(Bignum b, int *len)
32874aea 1607{
7cca0d81 1608 unsigned char *p;
32874aea 1609 int i, n = (bignum_bitcount(b) + 7) / 8;
3d88e64d 1610 p = snewn(n + 1, unsigned char);
7cca0d81 1611 if (!p)
32874aea 1612 fatalbox("out of memory");
7cca0d81 1613 p[0] = 0;
3709bfe9 1614 for (i = 1; i <= n; i++)
32874aea 1615 p[i] = bignum_byte(b, n - i);
7cca0d81 1616 i = 0;
32874aea 1617 while (i <= n && p[i] == 0 && (p[i + 1] & 0x80) == 0)
1618 i++;
1619 memmove(p, p + i, n + 1 - i);
1620 *len = n + 1 - i;
7cca0d81 1621 return p;
1622}
ff3187f6 1623static void ssh2_pkt_addmp(struct Packet *pkt, Bignum b)
32874aea 1624{
7cca0d81 1625 unsigned char *p;
1626 int len;
1627 p = ssh2_mpint_fmt(b, &len);
ff3187f6 1628 ssh2_pkt_addstring_start(pkt);
1629 ssh2_pkt_addstring_data(pkt, (char *)p, len);
dcbde236 1630 sfree(p);
7cca0d81 1631}
b185170a 1632
1633/*
1634 * Construct an SSH2 final-form packet: compress it, encrypt it,
1635 * put the MAC on it. Final packet, ready to be sent, is stored in
ff3187f6 1636 * pkt->data. Total length is returned.
b185170a 1637 */
ff3187f6 1638static int ssh2_pkt_construct(Ssh ssh, struct Packet *pkt)
32874aea 1639{
7cca0d81 1640 int cipherblk, maclen, padding, i;
7cca0d81 1641
a8327734 1642 if (ssh->logctx)
ff3187f6 1643 log_packet(ssh->logctx, PKT_OUTGOING, pkt->data[5],
1644 ssh2_pkt_type(ssh->pkt_ctx, pkt->data[5]),
1645 pkt->data + 6, pkt->length - 6,
1646 pkt->nblanks, pkt->blanks);
1647 sfree(pkt->blanks); pkt->blanks = NULL;
1648 pkt->nblanks = 0;
00db133f 1649
7cca0d81 1650 /*
4ba9b64b 1651 * Compress packet payload.
1652 */
4ba9b64b 1653 {
1654 unsigned char *newpayload;
1655 int newlen;
51470298 1656 if (ssh->cscomp &&
ff3187f6 1657 ssh->cscomp->compress(ssh->cs_comp_ctx, pkt->data + 5,
1658 pkt->length - 5,
51470298 1659 &newpayload, &newlen)) {
ff3187f6 1660 pkt->length = 5;
1661 ssh2_pkt_adddata(pkt, newpayload, newlen);
dcbde236 1662 sfree(newpayload);
4ba9b64b 1663 }
1664 }
1665
1666 /*
7cca0d81 1667 * Add padding. At least four bytes, and must also bring total
1668 * length (minus MAC) up to a multiple of the block size.
1669 */
51470298 1670 cipherblk = ssh->cscipher ? ssh->cscipher->blksize : 8; /* block size */
32874aea 1671 cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
7cca0d81 1672 padding = 4;
32874aea 1673 padding +=
ff3187f6 1674 (cipherblk - (pkt->length + padding) % cipherblk) % cipherblk;
51470298 1675 maclen = ssh->csmac ? ssh->csmac->len : 0;
ff3187f6 1676 ssh2_pkt_ensure(pkt, pkt->length + padding + maclen);
1677 pkt->data[4] = padding;
7cca0d81 1678 for (i = 0; i < padding; i++)
ff3187f6 1679 pkt->data[pkt->length + i] = random_byte();
1680 PUT_32BIT(pkt->data, pkt->length + padding - 4);
51470298 1681 if (ssh->csmac)
ff3187f6 1682 ssh->csmac->generate(ssh->cs_mac_ctx, pkt->data,
1683 pkt->length + padding,
51470298 1684 ssh->v2_outgoing_sequence);
1685 ssh->v2_outgoing_sequence++; /* whether or not we MACed */
1686
1687 if (ssh->cscipher)
371e569c 1688 ssh->cscipher->encrypt(ssh->cs_cipher_ctx,
ff3187f6 1689 pkt->data, pkt->length + padding);
51470298 1690
9442dd57 1691 pkt->encrypted_len = pkt->length + padding;
1692
ff3187f6 1693 /* Ready-to-send packet starts at pkt->data. We return length. */
1694 return pkt->length + padding + maclen;
b185170a 1695}
1696
1697/*
590f6a5f 1698 * Routines called from the main SSH code to send packets. There
1699 * are quite a few of these, because we have two separate
1700 * mechanisms for delaying the sending of packets:
1701 *
1702 * - In order to send an IGNORE message and a password message in
1703 * a single fixed-length blob, we require the ability to
1704 * concatenate the encrypted forms of those two packets _into_ a
1705 * single blob and then pass it to our <network.h> transport
1706 * layer in one go. Hence, there's a deferment mechanism which
1707 * works after packet encryption.
1708 *
1709 * - In order to avoid sending any connection-layer messages
1710 * during repeat key exchange, we have to queue up any such
1711 * outgoing messages _before_ they are encrypted (and in
1712 * particular before they're allocated sequence numbers), and
1713 * then send them once we've finished.
1714 *
1715 * I call these mechanisms `defer' and `queue' respectively, so as
1716 * to distinguish them reasonably easily.
1717 *
1718 * The functions send_noqueue() and defer_noqueue() free the packet
1719 * structure they are passed. Every outgoing packet goes through
1720 * precisely one of these functions in its life; packets passed to
1721 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1722 * these or get queued, and then when the queue is later emptied
1723 * the packets are all passed to defer_noqueue().
b185170a 1724 */
590f6a5f 1725
1726/*
1727 * Send an SSH2 packet immediately, without queuing or deferring.
1728 */
1729static void ssh2_pkt_send_noqueue(Ssh ssh, struct Packet *pkt)
32874aea 1730{
5471d09a 1731 int len;
1732 int backlog;
ff3187f6 1733 len = ssh2_pkt_construct(ssh, pkt);
1734 backlog = sk_write(ssh->s, (char *)pkt->data, len);
5471d09a 1735 if (backlog > SSH_MAX_BACKLOG)
51470298 1736 ssh_throttle_all(ssh, 1, backlog);
9442dd57 1737
1738 ssh->outgoing_data_size += pkt->encrypted_len;
1739 if (!ssh->kex_in_progress &&
d57f70af 1740 ssh->max_data_size != 0 &&
1741 ssh->outgoing_data_size > ssh->max_data_size)
f382c87d 1742 do_ssh2_transport(ssh, "too much data sent", -1, NULL);
9442dd57 1743
ff3187f6 1744 ssh_free_packet(pkt);
b185170a 1745}
1746
1747/*
590f6a5f 1748 * Defer an SSH2 packet.
b185170a 1749 */
590f6a5f 1750static void ssh2_pkt_defer_noqueue(Ssh ssh, struct Packet *pkt)
32874aea 1751{
ff3187f6 1752 int len = ssh2_pkt_construct(ssh, pkt);
51470298 1753 if (ssh->deferred_len + len > ssh->deferred_size) {
1754 ssh->deferred_size = ssh->deferred_len + len + 128;
3d88e64d 1755 ssh->deferred_send_data = sresize(ssh->deferred_send_data,
1756 ssh->deferred_size,
1757 unsigned char);
b185170a 1758 }
ff3187f6 1759 memcpy(ssh->deferred_send_data + ssh->deferred_len, pkt->data, len);
51470298 1760 ssh->deferred_len += len;
9442dd57 1761 ssh->deferred_data_size += pkt->encrypted_len;
ff3187f6 1762 ssh_free_packet(pkt);
b185170a 1763}
1764
1765/*
590f6a5f 1766 * Queue an SSH2 packet.
1767 */
1768static void ssh2_pkt_queue(Ssh ssh, struct Packet *pkt)
1769{
1770 assert(ssh->queueing);
1771
1772 if (ssh->queuelen >= ssh->queuesize) {
1773 ssh->queuesize = ssh->queuelen + 32;
1774 ssh->queue = sresize(ssh->queue, ssh->queuesize, struct Packet *);
1775 }
1776
1777 ssh->queue[ssh->queuelen++] = pkt;
1778}
1779
1780/*
1781 * Either queue or send a packet, depending on whether queueing is
1782 * set.
1783 */
1784static void ssh2_pkt_send(Ssh ssh, struct Packet *pkt)
1785{
1786 if (ssh->queueing)
1787 ssh2_pkt_queue(ssh, pkt);
1788 else
1789 ssh2_pkt_send_noqueue(ssh, pkt);
1790}
1791
1792/*
1793 * Either queue or defer a packet, depending on whether queueing is
1794 * set.
1795 */
1796static void ssh2_pkt_defer(Ssh ssh, struct Packet *pkt)
1797{
1798 if (ssh->queueing)
1799 ssh2_pkt_queue(ssh, pkt);
1800 else
1801 ssh2_pkt_defer_noqueue(ssh, pkt);
1802}
1803
1804/*
b185170a 1805 * Send the whole deferred data block constructed by
39065bed 1806 * ssh2_pkt_defer() or SSH1's defer_packet().
590f6a5f 1807 *
1808 * The expected use of the defer mechanism is that you call
1809 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1810 * not currently queueing, this simply sets up deferred_send_data
1811 * and then sends it. If we _are_ currently queueing, the calls to
1812 * ssh2_pkt_defer() put the deferred packets on to the queue
1813 * instead, and therefore ssh_pkt_defersend() has no deferred data
1814 * to send. Hence, there's no need to make it conditional on
1815 * ssh->queueing.
b185170a 1816 */
51470298 1817static void ssh_pkt_defersend(Ssh ssh)
32874aea 1818{
5471d09a 1819 int backlog;
d8baa528 1820 backlog = sk_write(ssh->s, (char *)ssh->deferred_send_data,
1821 ssh->deferred_len);
51470298 1822 ssh->deferred_len = ssh->deferred_size = 0;
1823 sfree(ssh->deferred_send_data);
1824 ssh->deferred_send_data = NULL;
5471d09a 1825 if (backlog > SSH_MAX_BACKLOG)
51470298 1826 ssh_throttle_all(ssh, 1, backlog);
9442dd57 1827
1828 ssh->outgoing_data_size += ssh->deferred_data_size;
1829 if (!ssh->kex_in_progress &&
d57f70af 1830 ssh->max_data_size != 0 &&
1831 ssh->outgoing_data_size > ssh->max_data_size)
f382c87d 1832 do_ssh2_transport(ssh, "too much data sent", -1, NULL);
9442dd57 1833 ssh->deferred_data_size = 0;
7cca0d81 1834}
1835
590f6a5f 1836/*
1837 * Send all queued SSH2 packets. We send them by means of
1838 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1839 * packets that needed to be lumped together.
1840 */
1841static void ssh2_pkt_queuesend(Ssh ssh)
1842{
1843 int i;
1844
1845 assert(!ssh->queueing);
1846
1847 for (i = 0; i < ssh->queuelen; i++)
1848 ssh2_pkt_defer_noqueue(ssh, ssh->queue[i]);
1849 ssh->queuelen = 0;
1850
1851 ssh_pkt_defersend(ssh);
1852}
1853
7cca0d81 1854#if 0
32874aea 1855void bndebug(char *string, Bignum b)
1856{
7cca0d81 1857 unsigned char *p;
1858 int i, len;
1859 p = ssh2_mpint_fmt(b, &len);
1860 debug(("%s", string));
1861 for (i = 0; i < len; i++)
32874aea 1862 debug((" %02x", p[i]));
765c4200 1863 debug(("\n"));
dcbde236 1864 sfree(p);
7cca0d81 1865}
1866#endif
1867
32874aea 1868static void sha_mpint(SHA_State * s, Bignum b)
1869{
7cca0d81 1870 unsigned char *p;
1871 int len;
1872 p = ssh2_mpint_fmt(b, &len);
1873 sha_string(s, p, len);
dcbde236 1874 sfree(p);
7cca0d81 1875}
1876
1877/*
0016d70b 1878 * Packet decode functions for both SSH1 and SSH2.
7cca0d81 1879 */
ff3187f6 1880static unsigned long ssh_pkt_getuint32(struct Packet *pkt)
32874aea 1881{
7cca0d81 1882 unsigned long value;
ff3187f6 1883 if (pkt->length - pkt->savedpos < 4)
32874aea 1884 return 0; /* arrgh, no way to decline (FIXME?) */
ff3187f6 1885 value = GET_32BIT(pkt->body + pkt->savedpos);
1886 pkt->savedpos += 4;
7cca0d81 1887 return value;
1888}
ff3187f6 1889static int ssh2_pkt_getbool(struct Packet *pkt)
32874aea 1890{
65a22376 1891 unsigned long value;
ff3187f6 1892 if (pkt->length - pkt->savedpos < 1)
32874aea 1893 return 0; /* arrgh, no way to decline (FIXME?) */
ff3187f6 1894 value = pkt->body[pkt->savedpos] != 0;
1895 pkt->savedpos++;
65a22376 1896 return value;
1897}
ff3187f6 1898static void ssh_pkt_getstring(struct Packet *pkt, char **p, int *length)
32874aea 1899{
57356d63 1900 int len;
7cca0d81 1901 *p = NULL;
45068b27 1902 *length = 0;
ff3187f6 1903 if (pkt->length - pkt->savedpos < 4)
32874aea 1904 return;
ff3187f6 1905 len = GET_32BIT(pkt->body + pkt->savedpos);
57356d63 1906 if (len < 0)
1907 return;
1908 *length = len;
ff3187f6 1909 pkt->savedpos += 4;
1910 if (pkt->length - pkt->savedpos < *length)
32874aea 1911 return;
ff3187f6 1912 *p = (char *)(pkt->body + pkt->savedpos);
1913 pkt->savedpos += *length;
7cca0d81 1914}
ff3187f6 1915static void *ssh_pkt_getdata(struct Packet *pkt, int length)
0016d70b 1916{
ff3187f6 1917 if (pkt->length - pkt->savedpos < length)
0016d70b 1918 return NULL;
ff3187f6 1919 pkt->savedpos += length;
1920 return pkt->body + (pkt->savedpos - length);
0016d70b 1921}
ff3187f6 1922static int ssh1_pkt_getrsakey(struct Packet *pkt, struct RSAKey *key,
0016d70b 1923 unsigned char **keystr)
1924{
1925 int j;
1926
ff3187f6 1927 j = makekey(pkt->body + pkt->savedpos,
1928 pkt->length - pkt->savedpos,
0016d70b 1929 key, keystr, 0);
1930
1931 if (j < 0)
1932 return FALSE;
1933
ff3187f6 1934 pkt->savedpos += j;
1935 assert(pkt->savedpos < pkt->length);
0016d70b 1936
1937 return TRUE;
1938}
ff3187f6 1939static Bignum ssh1_pkt_getmp(struct Packet *pkt)
0016d70b 1940{
1941 int j;
1942 Bignum b;
1943
ff3187f6 1944 j = ssh1_read_bignum(pkt->body + pkt->savedpos,
1945 pkt->length - pkt->savedpos, &b);
0016d70b 1946
1947 if (j < 0)
1948 return NULL;
1949
ff3187f6 1950 pkt->savedpos += j;
0016d70b 1951 return b;
1952}
ff3187f6 1953static Bignum ssh2_pkt_getmp(struct Packet *pkt)
32874aea 1954{
7cca0d81 1955 char *p;
3709bfe9 1956 int length;
7cca0d81 1957 Bignum b;
1958
ff3187f6 1959 ssh_pkt_getstring(pkt, &p, &length);
7cca0d81 1960 if (!p)
32874aea 1961 return NULL;
ff3187f6 1962 if (p[0] & 0x80)
32874aea 1963 return NULL;
d8baa528 1964 b = bignum_from_bytes((unsigned char *)p, length);
7cca0d81 1965 return b;
1966}
1967
7d503c31 1968/*
1dd353b5 1969 * Helper function to add an SSH2 signature blob to a packet.
1970 * Expects to be shown the public key blob as well as the signature
1971 * blob. Normally works just like ssh2_pkt_addstring, but will
1972 * fiddle with the signature packet if necessary for
1973 * BUG_SSH2_RSA_PADDING.
1974 */
ff3187f6 1975static void ssh2_add_sigblob(Ssh ssh, struct Packet *pkt,
1976 void *pkblob_v, int pkblob_len,
1dd353b5 1977 void *sigblob_v, int sigblob_len)
1978{
1979 unsigned char *pkblob = (unsigned char *)pkblob_v;
1980 unsigned char *sigblob = (unsigned char *)sigblob_v;
1981
1982 /* dmemdump(pkblob, pkblob_len); */
1983 /* dmemdump(sigblob, sigblob_len); */
1984
1985 /*
1986 * See if this is in fact an ssh-rsa signature and a buggy
1987 * server; otherwise we can just do this the easy way.
1988 */
51470298 1989 if ((ssh->remote_bugs & BUG_SSH2_RSA_PADDING) &&
1dd353b5 1990 (GET_32BIT(pkblob) == 7 && !memcmp(pkblob+4, "ssh-rsa", 7))) {
1991 int pos, len, siglen;
1992
1993 /*
1994 * Find the byte length of the modulus.
1995 */
1996
1997 pos = 4+7; /* skip over "ssh-rsa" */
1998 pos += 4 + GET_32BIT(pkblob+pos); /* skip over exponent */
1999 len = GET_32BIT(pkblob+pos); /* find length of modulus */
2000 pos += 4; /* find modulus itself */
2001 while (len > 0 && pkblob[pos] == 0)
2002 len--, pos++;
2003 /* debug(("modulus length is %d\n", len)); */
2004
2005 /*
2006 * Now find the signature integer.
2007 */
2008 pos = 4+7; /* skip over "ssh-rsa" */
2009 siglen = GET_32BIT(sigblob+pos);
2010 /* debug(("signature length is %d\n", siglen)); */
2011
2012 if (len != siglen) {
2013 unsigned char newlen[4];
ff3187f6 2014 ssh2_pkt_addstring_start(pkt);
2015 ssh2_pkt_addstring_data(pkt, (char *)sigblob, pos);
1dd353b5 2016 /* dmemdump(sigblob, pos); */
2017 pos += 4; /* point to start of actual sig */
2018 PUT_32BIT(newlen, len);
ff3187f6 2019 ssh2_pkt_addstring_data(pkt, (char *)newlen, 4);
1dd353b5 2020 /* dmemdump(newlen, 4); */
2021 newlen[0] = 0;
2022 while (len-- > siglen) {
ff3187f6 2023 ssh2_pkt_addstring_data(pkt, (char *)newlen, 1);
1dd353b5 2024 /* dmemdump(newlen, 1); */
2025 }
ff3187f6 2026 ssh2_pkt_addstring_data(pkt, (char *)(sigblob+pos), siglen);
1dd353b5 2027 /* dmemdump(sigblob+pos, siglen); */
2028 return;
2029 }
2030
2031 /* Otherwise fall through and do it the easy way. */
2032 }
2033
ff3187f6 2034 ssh2_pkt_addstring_start(pkt);
2035 ssh2_pkt_addstring_data(pkt, (char *)sigblob, sigblob_len);
1dd353b5 2036}
2037
2038/*
7d503c31 2039 * Examine the remote side's version string and compare it against
2040 * a list of known buggy implementations.
2041 */
51470298 2042static void ssh_detect_bugs(Ssh ssh, char *vstring)
32874aea 2043{
2044 char *imp; /* pointer to implementation part */
7d503c31 2045 imp = vstring;
2046 imp += strcspn(imp, "-");
bd358db1 2047 if (*imp) imp++;
7d503c31 2048 imp += strcspn(imp, "-");
bd358db1 2049 if (*imp) imp++;
7d503c31 2050
51470298 2051 ssh->remote_bugs = 0;
7d503c31 2052
5ecd7ad0 2053 if (ssh->cfg.sshbug_ignore1 == FORCE_ON ||
2054 (ssh->cfg.sshbug_ignore1 == AUTO &&
2c9c6388 2055 (!strcmp(imp, "1.2.18") || !strcmp(imp, "1.2.19") ||
2056 !strcmp(imp, "1.2.20") || !strcmp(imp, "1.2.21") ||
46ac09aa 2057 !strcmp(imp, "1.2.22") || !strcmp(imp, "Cisco-1.25") ||
bd0b4caf 2058 !strcmp(imp, "OSU_1.4alpha3") || !strcmp(imp, "OSU_1.5alpha4")))) {
32874aea 2059 /*
2060 * These versions don't support SSH1_MSG_IGNORE, so we have
2061 * to use a different defence against password length
2062 * sniffing.
2063 */
51470298 2064 ssh->remote_bugs |= BUG_CHOKES_ON_SSH1_IGNORE;
32874aea 2065 logevent("We believe remote version has SSH1 ignore bug");
7d503c31 2066 }
2067
5ecd7ad0 2068 if (ssh->cfg.sshbug_plainpw1 == FORCE_ON ||
2069 (ssh->cfg.sshbug_plainpw1 == AUTO &&
46ac09aa 2070 (!strcmp(imp, "Cisco-1.25") || !strcmp(imp, "OSU_1.4alpha3")))) {
bd358db1 2071 /*
2072 * These versions need a plain password sent; they can't
2073 * handle having a null and a random length of data after
2074 * the password.
2075 */
51470298 2076 ssh->remote_bugs |= BUG_NEEDS_SSH1_PLAIN_PASSWORD;
bd358db1 2077 logevent("We believe remote version needs a plain SSH1 password");
2078 }
2079
5ecd7ad0 2080 if (ssh->cfg.sshbug_rsa1 == FORCE_ON ||
2081 (ssh->cfg.sshbug_rsa1 == AUTO &&
2c9c6388 2082 (!strcmp(imp, "Cisco-1.25")))) {
0df73905 2083 /*
2084 * These versions apparently have no clue whatever about
2085 * RSA authentication and will panic and die if they see
2086 * an AUTH_RSA message.
2087 */
51470298 2088 ssh->remote_bugs |= BUG_CHOKES_ON_RSA;
0df73905 2089 logevent("We believe remote version can't handle RSA authentication");
2090 }
2091
5ecd7ad0 2092 if (ssh->cfg.sshbug_hmac2 == FORCE_ON ||
2093 (ssh->cfg.sshbug_hmac2 == AUTO &&
b9f387af 2094 !wc_match("* VShell", imp) &&
831301f6 2095 (wc_match("2.1.0*", imp) || wc_match("2.0.*", imp) ||
2096 wc_match("2.2.0*", imp) || wc_match("2.3.0*", imp) ||
2097 wc_match("2.1 *", imp)))) {
32874aea 2098 /*
2099 * These versions have the HMAC bug.
2100 */
51470298 2101 ssh->remote_bugs |= BUG_SSH2_HMAC;
32874aea 2102 logevent("We believe remote version has SSH2 HMAC bug");
7d503c31 2103 }
1dd353b5 2104
5ecd7ad0 2105 if (ssh->cfg.sshbug_derivekey2 == FORCE_ON ||
2106 (ssh->cfg.sshbug_derivekey2 == AUTO &&
b9f387af 2107 !wc_match("* VShell", imp) &&
2856a1b9 2108 (wc_match("2.0.0*", imp) || wc_match("2.0.10*", imp) ))) {
088bde77 2109 /*
2110 * These versions have the key-derivation bug (failing to
2111 * include the literal shared secret in the hashes that
2112 * generate the keys).
2113 */
51470298 2114 ssh->remote_bugs |= BUG_SSH2_DERIVEKEY;
088bde77 2115 logevent("We believe remote version has SSH2 key-derivation bug");
2116 }
2117
5ecd7ad0 2118 if (ssh->cfg.sshbug_rsapad2 == FORCE_ON ||
2119 (ssh->cfg.sshbug_rsapad2 == AUTO &&
831301f6 2120 (wc_match("OpenSSH_2.[5-9]*", imp) ||
2121 wc_match("OpenSSH_3.[0-2]*", imp)))) {
1dd353b5 2122 /*
2123 * These versions have the SSH2 RSA padding bug.
2124 */
51470298 2125 ssh->remote_bugs |= BUG_SSH2_RSA_PADDING;
1dd353b5 2126 logevent("We believe remote version has SSH2 RSA padding bug");
2127 }
8e975795 2128
dda87a28 2129 if (ssh->cfg.sshbug_pksessid2 == FORCE_ON ||
2130 (ssh->cfg.sshbug_pksessid2 == AUTO &&
2131 wc_match("OpenSSH_2.[0-2]*", imp))) {
2132 /*
2133 * These versions have the SSH2 session-ID bug in
2134 * public-key authentication.
2135 */
2136 ssh->remote_bugs |= BUG_SSH2_PK_SESSIONID;
2137 logevent("We believe remote version has SSH2 public-key-session-ID bug");
2138 }
f382c87d 2139
2140 if (ssh->cfg.sshbug_rekey2 == FORCE_ON ||
2141 (ssh->cfg.sshbug_rekey2 == AUTO &&
2142 wc_match("Sun_SSH_1.0", imp))) {
2143 /*
2144 * These versions have the SSH2 ignore-rekey bug.
2145 */
2146 ssh->remote_bugs |= BUG_SSH2_REKEY;
2147 logevent("We believe remote version has SSH2 ignore-rekey bug");
2148 }
7d503c31 2149}
2150
d38d6a1f 2151/*
2152 * The `software version' part of an SSH version string is required
2153 * to contain no spaces or minus signs.
2154 */
2155static void ssh_fix_verstring(char *str)
2156{
2157 /* Eat "SSH-<protoversion>-". */
2158 assert(*str == 'S'); str++;
2159 assert(*str == 'S'); str++;
2160 assert(*str == 'H'); str++;
2161 assert(*str == '-'); str++;
2162 while (*str && *str != '-') str++;
2163 assert(*str == '-'); str++;
2164
2165 /* Convert minus signs and spaces in the remaining string into
2166 * underscores. */
2167 while (*str) {
2168 if (*str == '-' || *str == ' ')
2169 *str = '_';
2170 str++;
2171 }
2172}
2173
51470298 2174static int do_ssh_init(Ssh ssh, unsigned char c)
32874aea 2175{
51470298 2176 struct do_ssh_init_state {
2177 int vslen;
2178 char version[10];
2179 char *vstring;
2180 int vstrsize;
2181 int i;
2182 int proto1, proto2;
2183 };
2184 crState(do_ssh_init_state);
374330e2 2185
51470298 2186 crBegin(ssh->do_ssh_init_crstate);
8df7a775 2187
2188 /* Search for the string "SSH-" in the input. */
51470298 2189 s->i = 0;
8df7a775 2190 while (1) {
2191 static const int transS[] = { 1, 2, 2, 1 };
2192 static const int transH[] = { 0, 0, 3, 0 };
2193 static const int transminus[] = { 0, 0, 0, -1 };
32874aea 2194 if (c == 'S')
51470298 2195 s->i = transS[s->i];
32874aea 2196 else if (c == 'H')
51470298 2197 s->i = transH[s->i];
32874aea 2198 else if (c == '-')
51470298 2199 s->i = transminus[s->i];
32874aea 2200 else
51470298 2201 s->i = 0;
2202 if (s->i < 0)
8df7a775 2203 break;
2204 crReturn(1); /* get another character */
374330e2 2205 }
8df7a775 2206
51470298 2207 s->vstrsize = 16;
3d88e64d 2208 s->vstring = snewn(s->vstrsize, char);
51470298 2209 strcpy(s->vstring, "SSH-");
2210 s->vslen = 4;
2211 s->i = 0;
374330e2 2212 while (1) {
8df7a775 2213 crReturn(1); /* get another char */
51470298 2214 if (s->vslen >= s->vstrsize - 1) {
2215 s->vstrsize += 16;
3d88e64d 2216 s->vstring = sresize(s->vstring, s->vstrsize, char);
32874aea 2217 }
51470298 2218 s->vstring[s->vslen++] = c;
2219 if (s->i >= 0) {
374330e2 2220 if (c == '-') {
51470298 2221 s->version[s->i] = '\0';
2222 s->i = -1;
2223 } else if (s->i < sizeof(s->version) - 1)
2224 s->version[s->i++] = c;
c4ffc4d0 2225 } else if (c == '\012')
374330e2 2226 break;
2227 }
2228
51470298 2229 ssh->agentfwd_enabled = FALSE;
2230 ssh->rdpkt2_state.incoming_sequence = 0;
960e736a 2231
51470298 2232 s->vstring[s->vslen] = 0;
a7d4653a 2233 s->vstring[strcspn(s->vstring, "\015\012")] = '\0';/* remove EOL chars */
51470298 2234 {
2235 char *vlog;
3d88e64d 2236 vlog = snewn(20 + s->vslen, char);
51470298 2237 sprintf(vlog, "Server version: %s", s->vstring);
2238 logevent(vlog);
2239 sfree(vlog);
2240 }
2241 ssh_detect_bugs(ssh, s->vstring);
c5e9c988 2242
adf799dd 2243 /*
38d228a2 2244 * Decide which SSH protocol version to support.
adf799dd 2245 */
38d228a2 2246
2247 /* Anything strictly below "2.0" means protocol 1 is supported. */
51470298 2248 s->proto1 = ssh_versioncmp(s->version, "2.0") < 0;
38d228a2 2249 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
51470298 2250 s->proto2 = ssh_versioncmp(s->version, "1.99") >= 0;
38d228a2 2251
86916870 2252 if (ssh->cfg.sshprot == 0 && !s->proto1) {
6b5cf8b4 2253 bombout(("SSH protocol version 1 required by user but not provided by server"));
7ffdbc1a 2254 crStop(0);
38d228a2 2255 }
86916870 2256 if (ssh->cfg.sshprot == 3 && !s->proto2) {
6b5cf8b4 2257 bombout(("SSH protocol version 2 required by user but not provided by server"));
7ffdbc1a 2258 crStop(0);
38d228a2 2259 }
2260
d38d6a1f 2261 {
2262 char *verstring;
2263
2264 if (s->proto2 && (ssh->cfg.sshprot >= 2 || !s->proto1)) {
2265 /*
2266 * Construct a v2 version string.
2267 */
a7d4653a 2268 verstring = dupprintf("SSH-2.0-%s\015\012", sshver);
d38d6a1f 2269 ssh->version = 2;
2270 } else {
2271 /*
2272 * Construct a v1 version string.
2273 */
a7d4653a 2274 verstring = dupprintf("SSH-%s-%s\012",
d38d6a1f 2275 (ssh_versioncmp(s->version, "1.5") <= 0 ?
2276 s->version : "1.5"),
2277 sshver);
2278 ssh->version = 1;
2279 }
2280
2281 ssh_fix_verstring(verstring);
2282
2283 if (ssh->version == 2) {
2284 /*
2285 * Hash our version string and their version string.
2286 */
2287 SHA_Init(&ssh->exhashbase);
0b351b6b 2288 sha_string(&ssh->exhashbase, verstring,
a7d4653a 2289 strcspn(verstring, "\015\012"));
0b351b6b 2290 sha_string(&ssh->exhashbase, s->vstring,
a7d4653a 2291 strcspn(s->vstring, "\015\012"));
d38d6a1f 2292
2293 /*
2294 * Initialise SSHv2 protocol.
2295 */
2296 ssh->protocol = ssh2_protocol;
2297 ssh2_protocol_setup(ssh);
2298 ssh->s_rdpkt = ssh2_rdpkt;
2299 } else {
2300 /*
2301 * Initialise SSHv1 protocol.
2302 */
2303 ssh->protocol = ssh1_protocol;
2304 ssh1_protocol_setup(ssh);
2305 ssh->s_rdpkt = ssh1_rdpkt;
2306 }
2307 logeventf(ssh, "We claim version: %.*s",
a7d4653a 2308 strcspn(verstring, "\015\012"), verstring);
51470298 2309 sk_write(ssh->s, verstring, strlen(verstring));
d38d6a1f 2310 sfree(verstring);
e5574168 2311 }
d38d6a1f 2312
2313 logeventf(ssh, "Using SSH protocol version %d", ssh->version);
2314
125105d1 2315 update_specials_menu(ssh->frontend);
51470298 2316 ssh->state = SSH_STATE_BEFORE_SIZE;
39934deb 2317 ssh->pinger = pinger_new(&ssh->cfg, &ssh_backend, ssh);
8df7a775 2318
51470298 2319 sfree(s->vstring);
50526e47 2320
8df7a775 2321 crFinish(0);
2322}
2323
51470298 2324static void ssh_gotdata(Ssh ssh, unsigned char *data, int datalen)
8df7a775 2325{
51470298 2326 crBegin(ssh->ssh_gotdata_crstate);
8df7a775 2327
2328 /*
2329 * To begin with, feed the characters one by one to the
2330 * protocol initialisation / selection function do_ssh_init().
2331 * When that returns 0, we're done with the initial greeting
2332 * exchange and can move on to packet discipline.
2333 */
2334 while (1) {
51470298 2335 int ret; /* need not be kept across crReturn */
8df7a775 2336 if (datalen == 0)
2337 crReturnV; /* more data please */
51470298 2338 ret = do_ssh_init(ssh, *data);
32874aea 2339 data++;
2340 datalen--;
8df7a775 2341 if (ret == 0)
2342 break;
2343 }
2344
2345 /*
2346 * We emerge from that loop when the initial negotiation is
2347 * over and we have selected an s_rdpkt function. Now pass
2348 * everything to s_rdpkt, and then pass the resulting packets
2349 * to the proper protocol handler.
2350 */
2351 if (datalen == 0)
2352 crReturnV;
2353 while (1) {
2354 while (datalen > 0) {
ff3187f6 2355 struct Packet *pktin = ssh->s_rdpkt(ssh, &data, &datalen);
2356 if (pktin) {
2357 ssh->protocol(ssh, NULL, 0, pktin);
2358 ssh_free_packet(pktin);
8df7a775 2359 }
ff3187f6 2360 if (ssh->state == SSH_STATE_CLOSED)
2361 return;
8df7a775 2362 }
2363 crReturnV;
2364 }
2365 crFinishV;
2366}
2367
36f94d1f 2368static void ssh_do_close(Ssh ssh)
32874aea 2369{
36f94d1f 2370 int i;
2371 struct ssh_channel *c;
2372
51470298 2373 ssh->state = SSH_STATE_CLOSED;
2374 if (ssh->s) {
2375 sk_close(ssh->s);
2376 ssh->s = NULL;
39934deb 2377 notify_remote_exit(ssh->frontend);
f3ab576e 2378 }
36f94d1f 2379 /*
2380 * Now we must shut down any port and X forwardings going
2381 * through this connection.
2382 */
74a98066 2383 if (ssh->channels) {
2384 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
2385 switch (c->type) {
2386 case CHAN_X11:
2387 x11_close(c->u.x11.s);
2388 break;
2389 case CHAN_SOCKDATA:
2390 pfd_close(c->u.pfd.s);
2391 break;
2392 }
2393 del234(ssh->channels, c);
2394 if (ssh->version == 2)
2395 bufchain_clear(&c->v.v2.outbuffer);
2396 sfree(c);
36f94d1f 2397 }
36f94d1f 2398 }
2399}
2400
cbe2d68f 2401static int ssh_closing(Plug plug, const char *error_msg, int error_code,
36f94d1f 2402 int calling_back)
2403{
2404 Ssh ssh = (Ssh) plug;
2405 ssh_do_close(ssh);
7e78000d 2406 if (error_msg) {
32874aea 2407 /* A socket error has occurred. */
247308b5 2408 logevent(error_msg);
971bcc0a 2409 connection_fatal(ssh->frontend, "%s", error_msg);
7e78000d 2410 } else {
2411 /* Otherwise, the remote side closed the connection normally. */
8df7a775 2412 }
7e78000d 2413 return 0;
2414}
2415
32874aea 2416static int ssh_receive(Plug plug, int urgent, char *data, int len)
2417{
51470298 2418 Ssh ssh = (Ssh) plug;
d8baa528 2419 ssh_gotdata(ssh, (unsigned char *)data, len);
51470298 2420 if (ssh->state == SSH_STATE_CLOSED) {
36f94d1f 2421 ssh_do_close(ssh);
32874aea 2422 return 0;
3257deae 2423 }
fef97f43 2424 return 1;
374330e2 2425}
2426
5471d09a 2427static void ssh_sent(Plug plug, int bufsize)
2428{
51470298 2429 Ssh ssh = (Ssh) plug;
5471d09a 2430 /*
2431 * If the send backlog on the SSH socket itself clears, we
2432 * should unthrottle the whole world if it was throttled.
2433 */
2434 if (bufsize < SSH_MAX_BACKLOG)
51470298 2435 ssh_throttle_all(ssh, 0, bufsize);
5471d09a 2436}
2437
fb09bf1c 2438/*
8df7a775 2439 * Connect to specified host and port.
2440 * Returns an error message, or NULL on success.
6e1ebb76 2441 * Also places the canonical host name into `realhost'. It must be
2442 * freed by the caller.
8df7a775 2443 */
cbe2d68f 2444static const char *connect_to_host(Ssh ssh, char *host, int port,
79bf227b 2445 char **realhost, int nodelay, int keepalive)
8df7a775 2446{
51470298 2447 static const struct plug_function_table fn_table = {
7e78000d 2448 ssh_closing,
5471d09a 2449 ssh_receive,
2450 ssh_sent,
2451 NULL
51470298 2452 };
7e78000d 2453
8df7a775 2454 SockAddr addr;
cbe2d68f 2455 const char *err;
8df7a775 2456
3d88e64d 2457 ssh->savedhost = snewn(1 + strlen(host), char);
51470298 2458 if (!ssh->savedhost)
8df7a775 2459 fatalbox("Out of memory");
51470298 2460 strcpy(ssh->savedhost, host);
8df7a775 2461
2462 if (port < 0)
2463 port = 22; /* default ssh port */
51470298 2464 ssh->savedport = port;
8df7a775 2465
2466 /*
2467 * Try to find host.
2468 */
05581745 2469 logeventf(ssh, "Looking up host \"%s\"%s", host,
2470 (ssh->cfg.addressfamily == ADDRTYPE_IPV4 ? " (IPv4)" :
2471 (ssh->cfg.addressfamily == ADDRTYPE_IPV6 ? " (IPv6)" : "")));
2472 addr = name_lookup(host, port, realhost, &ssh->cfg,
2473 ssh->cfg.addressfamily);
170c1e6e 2474 if ((err = sk_addr_error(addr)) != NULL) {
2475 sk_addr_free(addr);
8df7a775 2476 return err;
170c1e6e 2477 }
8df7a775 2478
8df7a775 2479 /*
2480 * Open socket.
2481 */
3ad9d396 2482 {
57356d63 2483 char addrbuf[100];
3ad9d396 2484 sk_getaddr(addr, addrbuf, 100);
57356d63 2485 logeventf(ssh, "Connecting to %s port %d", addrbuf, port);
3ad9d396 2486 }
51470298 2487 ssh->fn = &fn_table;
e8fa8f62 2488 ssh->s = new_connection(addr, *realhost, port,
79bf227b 2489 0, 1, nodelay, keepalive, (Plug) ssh, &ssh->cfg);
70e5d0fd 2490 if ((err = sk_socket_error(ssh->s)) != NULL) {
51470298 2491 ssh->s = NULL;
39934deb 2492 notify_remote_exit(ssh->frontend);
8df7a775 2493 return err;
67c4ba2e 2494 }
8df7a775 2495
8df7a775 2496 return NULL;
2497}
2498
2499/*
5471d09a 2500 * Throttle or unthrottle the SSH connection.
2501 */
51470298 2502static void ssh1_throttle(Ssh ssh, int adjust)
5471d09a 2503{
51470298 2504 int old_count = ssh->v1_throttle_count;
2505 ssh->v1_throttle_count += adjust;
2506 assert(ssh->v1_throttle_count >= 0);
2507 if (ssh->v1_throttle_count && !old_count) {
2508 sk_set_frozen(ssh->s, 1);
2509 } else if (!ssh->v1_throttle_count && old_count) {
2510 sk_set_frozen(ssh->s, 0);
5471d09a 2511 }
2512}
2513
2514/*
2515 * Throttle or unthrottle _all_ local data streams (for when sends
2516 * on the SSH connection itself back up).
2517 */
51470298 2518static void ssh_throttle_all(Ssh ssh, int enable, int bufsize)
5471d09a 2519{
2520 int i;
2521 struct ssh_channel *c;
2522
51470298 2523 if (enable == ssh->throttled_all)
5471d09a 2524 return;
51470298 2525 ssh->throttled_all = enable;
2526 ssh->overall_bufsize = bufsize;
2527 if (!ssh->channels)
5471d09a 2528 return;
51470298 2529 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
5471d09a 2530 switch (c->type) {
2531 case CHAN_MAINSESSION:
2532 /*
2533 * This is treated separately, outside the switch.
2534 */
2535 break;
2536 case CHAN_X11:
2537 x11_override_throttle(c->u.x11.s, enable);
2538 break;
2539 case CHAN_AGENT:
2540 /* Agent channels require no buffer management. */
2541 break;
2542 case CHAN_SOCKDATA:
36f94d1f 2543 pfd_override_throttle(c->u.pfd.s, enable);
5471d09a 2544 break;
2545 }
2546 }
2547}
2548
2549/*
51470298 2550 * Username and password input, abstracted off into routines
2551 * reusable in several places - even between SSH1 and SSH2.
0405e71f 2552 */
0405e71f 2553
2554/* Set up a username or password input loop on a given buffer. */
ae9ae89f 2555static void setup_userpass_input(Ssh ssh, char *buffer, int buflen, int echo)
0405e71f 2556{
51470298 2557 ssh->userpass_input_buffer = buffer;
2558 ssh->userpass_input_buflen = buflen;
2559 ssh->userpass_input_bufpos = 0;
2560 ssh->userpass_input_echo = echo;
0405e71f 2561}
2562
2563/*
2564 * Process some terminal data in the course of username/password
2565 * input. Returns >0 for success (line of input returned in
2566 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2567 * for inconclusive (keep waiting for more input please).
2568 */
ae9ae89f 2569static int process_userpass_input(Ssh ssh, unsigned char *in, int inlen)
0405e71f 2570{
2571 char c;
2572
2573 while (inlen--) {
2574 switch (c = *in++) {
2575 case 10:
2576 case 13:
51470298 2577 ssh->userpass_input_buffer[ssh->userpass_input_bufpos] = 0;
2578 ssh->userpass_input_buffer[ssh->userpass_input_buflen-1] = 0;
0405e71f 2579 return +1;
2580 break;
2581 case 8:
2582 case 127:
51470298 2583 if (ssh->userpass_input_bufpos > 0) {
2584 if (ssh->userpass_input_echo)
2585 c_write_str(ssh, "\b \b");
2586 ssh->userpass_input_bufpos--;
0405e71f 2587 }
2588 break;
2589 case 21:
2590 case 27:
51470298 2591 while (ssh->userpass_input_bufpos > 0) {
2592 if (ssh->userpass_input_echo)
2593 c_write_str(ssh, "\b \b");
2594 ssh->userpass_input_bufpos--;
0405e71f 2595 }
2596 break;
2597 case 3:
2598 case 4:
2599 return -1;
2600 break;
2601 default:
4692a14a 2602 /*
2603 * This simplistic check for printability is disabled
2604 * when we're doing password input, because some people
2605 * have control characters in their passwords.o
2606 */
2607 if ((!ssh->userpass_input_echo ||
2608 (c >= ' ' && c <= '~') ||
0405e71f 2609 ((unsigned char) c >= 160))
51470298 2610 && ssh->userpass_input_bufpos < ssh->userpass_input_buflen-1) {
2611 ssh->userpass_input_buffer[ssh->userpass_input_bufpos++] = c;
2612 if (ssh->userpass_input_echo)
2613 c_write(ssh, &c, 1);
0405e71f 2614 }
2615 break;
2616 }
2617 }
2618 return 0;
2619}
2620
f11d78f2 2621static void ssh_agent_callback(void *sshv, void *reply, int replylen)
839f10db 2622{
2623 Ssh ssh = (Ssh) sshv;
2624
2625 ssh->agent_response = reply;
2626 ssh->agent_response_len = replylen;
2627
2628 if (ssh->version == 1)
ff3187f6 2629 do_ssh1_login(ssh, NULL, -1, NULL);
839f10db 2630 else
ff3187f6 2631 do_ssh2_authconn(ssh, NULL, -1, NULL);
839f10db 2632}
2633
f11d78f2 2634static void ssh_agentf_callback(void *cv, void *reply, int replylen)
839f10db 2635{
2636 struct ssh_channel *c = (struct ssh_channel *)cv;
2637 Ssh ssh = c->ssh;
2638 void *sentreply = reply;
2639
2640 if (!sentreply) {
2641 /* Fake SSH_AGENT_FAILURE. */
2642 sentreply = "\0\0\0\1\5";
2643 replylen = 5;
2644 }
2645 if (ssh->version == 2) {
2646 ssh2_add_channel_data(c, sentreply, replylen);
2647 ssh2_try_send(c);
2648 } else {
2649 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
2650 PKT_INT, c->remoteid,
9a10ecf4 2651 PKTT_DATA,
839f10db 2652 PKT_INT, replylen,
2653 PKT_DATA, sentreply, replylen,
9a10ecf4 2654 PKTT_OTHER,
839f10db 2655 PKT_END);
2656 }
2657 if (reply)
2658 sfree(reply);
2659}
2660
0405e71f 2661/*
fb09bf1c 2662 * Handle the key exchange and user authentication phases.
2663 */
ff3187f6 2664static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen,
2665 struct Packet *pktin)
fb09bf1c 2666{
0016d70b 2667 int i, j, ret;
2668 unsigned char cookie[8], *ptr;
374330e2 2669 struct RSAKey servkey, hostkey;
2670 struct MD5Context md5c;
51470298 2671 struct do_ssh1_login_state {
2672 int len;
2673 unsigned char *rsabuf, *keystr1, *keystr2;
2674 unsigned long supported_ciphers_mask, supported_auths_mask;
2675 int tried_publickey, tried_agent;
2676 int tis_auth_refused, ccard_auth_refused;
2677 unsigned char session_id[16];
2678 int cipher_type;
2679 char username[100];
2680 void *publickey_blob;
2681 int publickey_bloblen;
2682 char password[100];
2683 char prompt[200];
2684 int pos;
2685 char c;
2686 int pwpkt_type;
2687 unsigned char request[5], *response, *p;
2688 int responselen;
2689 int keyi, nkeys;
2690 int authed;
2691 struct RSAKey key;
2692 Bignum challenge;
2693 char *commentp;
2694 int commentlen;
2695 };
2696 crState(do_ssh1_login_state);
2697
2698 crBegin(ssh->do_ssh1_login_crstate);
374330e2 2699
ff3187f6 2700 if (!pktin)
2701 crWaitUntil(pktin);
374330e2 2702
ff3187f6 2703 if (pktin->type != SSH1_SMSG_PUBLIC_KEY) {
6b5cf8b4 2704 bombout(("Public key packet not received"));
7ffdbc1a 2705 crStop(0);
8d5de777 2706 }
374330e2 2707
c5e9c988 2708 logevent("Received public keys");
374330e2 2709
ff3187f6 2710 ptr = ssh_pkt_getdata(pktin, 8);
0016d70b 2711 if (!ptr) {
2712 bombout(("SSH1 public key packet stopped before random cookie"));
2713 crStop(0);
2714 }
2715 memcpy(cookie, ptr, 8);
374330e2 2716
ff3187f6 2717 if (!ssh1_pkt_getrsakey(pktin, &servkey, &s->keystr1) ||
2718 !ssh1_pkt_getrsakey(pktin, &hostkey, &s->keystr2)) {
ae0500e5 2719 bombout(("Failed to read SSH1 public keys from public key packet"));
0016d70b 2720 crStop(0);
2721 }
374330e2 2722
c5e9c988 2723 /*
1c2a93c4 2724 * Log the host key fingerprint.
c5e9c988 2725 */
c5e9c988 2726 {
2727 char logmsg[80];
1c2a93c4 2728 logevent("Host key fingerprint is:");
c5e9c988 2729 strcpy(logmsg, " ");
32874aea 2730 hostkey.comment = NULL;
2731 rsa_fingerprint(logmsg + strlen(logmsg),
2732 sizeof(logmsg) - strlen(logmsg), &hostkey);
c5e9c988 2733 logevent(logmsg);
2734 }
2735
ff3187f6 2736 ssh->v1_remote_protoflags = ssh_pkt_getuint32(pktin);
2737 s->supported_ciphers_mask = ssh_pkt_getuint32(pktin);
2738 s->supported_auths_mask = ssh_pkt_getuint32(pktin);
bea1ef5f 2739
51470298 2740 ssh->v1_local_protoflags =
2741 ssh->v1_remote_protoflags & SSH1_PROTOFLAGS_SUPPORTED;
2742 ssh->v1_local_protoflags |= SSH1_PROTOFLAG_SCREEN_NUMBER;
b96dc54c 2743
c5e9c988 2744 MD5Init(&md5c);
51470298 2745 MD5Update(&md5c, s->keystr2, hostkey.bytes);
2746 MD5Update(&md5c, s->keystr1, servkey.bytes);
0016d70b 2747 MD5Update(&md5c, cookie, 8);
51470298 2748 MD5Final(s->session_id, &md5c);
374330e2 2749
32874aea 2750 for (i = 0; i < 32; i++)
51470298 2751 ssh->session_key[i] = random_byte();
374330e2 2752
0016d70b 2753 /*
2754 * Verify that the `bits' and `bytes' parameters match.
2755 */
2756 if (hostkey.bits > hostkey.bytes * 8 ||
2757 servkey.bits > servkey.bytes * 8) {
2758 bombout(("SSH1 public keys were badly formatted"));
2759 crStop(0);
2760 }
2761
51470298 2762 s->len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
374330e2 2763
3d88e64d 2764 s->rsabuf = snewn(s->len, unsigned char);
51470298 2765 if (!s->rsabuf)
374330e2 2766 fatalbox("Out of memory");
2767
89ee5268 2768 /*
2769 * Verify the host key.
2770 */
2771 {
32874aea 2772 /*
2773 * First format the key into a string.
2774 */
2775 int len = rsastr_len(&hostkey);
2776 char fingerprint[100];
3d88e64d 2777 char *keystr = snewn(len, char);
32874aea 2778 if (!keystr)
2779 fatalbox("Out of memory");
2780 rsastr_fmt(keystr, &hostkey);
2781 rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
a8327734 2782 verify_ssh_host_key(ssh->frontend,
2783 ssh->savedhost, ssh->savedport, "rsa", keystr,
32874aea 2784 fingerprint);
2785 sfree(keystr);
2786 }
2787
2788 for (i = 0; i < 32; i++) {
51470298 2789 s->rsabuf[i] = ssh->session_key[i];
374330e2 2790 if (i < 16)
51470298 2791 s->rsabuf[i] ^= s->session_id[i];
374330e2 2792 }
2793
2794 if (hostkey.bytes > servkey.bytes) {
0016d70b 2795 ret = rsaencrypt(s->rsabuf, 32, &servkey);
2796 if (ret)
2797 ret = rsaencrypt(s->rsabuf, servkey.bytes, &hostkey);
374330e2 2798 } else {
0016d70b 2799 ret = rsaencrypt(s->rsabuf, 32, &hostkey);
2800 if (ret)
2801 ret = rsaencrypt(s->rsabuf, hostkey.bytes, &servkey);
2802 }
2803 if (!ret) {
2804 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2805 crStop(0);
374330e2 2806 }
2807
c5e9c988 2808 logevent("Encrypted session key");
2809
ca20bfcf 2810 {
2811 int cipher_chosen = 0, warn = 0;
2812 char *cipher_string = NULL;
51470298 2813 int i;
ca20bfcf 2814 for (i = 0; !cipher_chosen && i < CIPHER_MAX; i++) {
86916870 2815 int next_cipher = ssh->cfg.ssh_cipherlist[i];
ca20bfcf 2816 if (next_cipher == CIPHER_WARN) {
2817 /* If/when we choose a cipher, warn about it */
2818 warn = 1;
2819 } else if (next_cipher == CIPHER_AES) {
2820 /* XXX Probably don't need to mention this. */
2821 logevent("AES not supported in SSH1, skipping");
2822 } else {
2823 switch (next_cipher) {
51470298 2824 case CIPHER_3DES: s->cipher_type = SSH_CIPHER_3DES;
ca20bfcf 2825 cipher_string = "3DES"; break;
51470298 2826 case CIPHER_BLOWFISH: s->cipher_type = SSH_CIPHER_BLOWFISH;
ca20bfcf 2827 cipher_string = "Blowfish"; break;
51470298 2828 case CIPHER_DES: s->cipher_type = SSH_CIPHER_DES;
ca20bfcf 2829 cipher_string = "single-DES"; break;
2830 }
51470298 2831 if (s->supported_ciphers_mask & (1 << s->cipher_type))
ca20bfcf 2832 cipher_chosen = 1;
2833 }
2834 }
2835 if (!cipher_chosen) {
51470298 2836 if ((s->supported_ciphers_mask & (1 << SSH_CIPHER_3DES)) == 0)
6b5cf8b4 2837 bombout(("Server violates SSH 1 protocol by not "
ca20bfcf 2838 "supporting 3DES encryption"));
2839 else
2840 /* shouldn't happen */
6b5cf8b4 2841 bombout(("No supported ciphers found"));
7ffdbc1a 2842 crStop(0);
a99a05c0 2843 }
ca20bfcf 2844
2845 /* Warn about chosen cipher if necessary. */
bb348ab1 2846 if (warn) {
2847 sk_set_frozen(ssh->s, 1);
83e7d008 2848 askalg(ssh->frontend, "cipher", cipher_string);
bb348ab1 2849 sk_set_frozen(ssh->s, 0);
2850 }
bea1ef5f 2851 }
ca20bfcf 2852
51470298 2853 switch (s->cipher_type) {
32874aea 2854 case SSH_CIPHER_3DES:
2855 logevent("Using 3DES encryption");
2856 break;
2857 case SSH_CIPHER_DES:
2858 logevent("Using single-DES encryption");
2859 break;
2860 case SSH_CIPHER_BLOWFISH:
2861 logevent("Using Blowfish encryption");
2862 break;
c5e9c988 2863 }
bea1ef5f 2864
51470298 2865 send_packet(ssh, SSH1_CMSG_SESSION_KEY,
2866 PKT_CHAR, s->cipher_type,
32874aea 2867 PKT_DATA, cookie, 8,
51470298 2868 PKT_CHAR, (s->len * 8) >> 8, PKT_CHAR, (s->len * 8) & 0xFF,
2869 PKT_DATA, s->rsabuf, s->len,
2870 PKT_INT, ssh->v1_local_protoflags, PKT_END);
fb09bf1c 2871
c5e9c988 2872 logevent("Trying to enable encryption...");
374330e2 2873
51470298 2874 sfree(s->rsabuf);
374330e2 2875
51470298 2876 ssh->cipher = (s->cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
2877 s->cipher_type == SSH_CIPHER_DES ? &ssh_des :
2878 &ssh_3des);
371e569c 2879 ssh->v1_cipher_ctx = ssh->cipher->make_context();
2880 ssh->cipher->sesskey(ssh->v1_cipher_ctx, ssh->session_key);
57356d63 2881 logeventf(ssh, "Initialised %s encryption", ssh->cipher->text_name);
374330e2 2882
0183b242 2883 ssh->crcda_ctx = crcda_make_context();
2884 logevent("Installing CRC compensation attack detector");
2885
679539d7 2886 if (servkey.modulus) {
2887 sfree(servkey.modulus);
2888 servkey.modulus = NULL;
2889 }
2890 if (servkey.exponent) {
2891 sfree(servkey.exponent);
2892 servkey.exponent = NULL;
2893 }
2894 if (hostkey.modulus) {
2895 sfree(hostkey.modulus);
2896 hostkey.modulus = NULL;
2897 }
2898 if (hostkey.exponent) {
2899 sfree(hostkey.exponent);
2900 hostkey.exponent = NULL;
2901 }
ff3187f6 2902 crWaitUntil(pktin);
374330e2 2903
ff3187f6 2904 if (pktin->type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 2905 bombout(("Encryption not successfully enabled"));
7ffdbc1a 2906 crStop(0);
8d5de777 2907 }
374330e2 2908
c5e9c988 2909 logevent("Successfully started encryption");
2910
374330e2 2911 fflush(stdout);
2912 {
aa09f7d0 2913 if (!*ssh->cfg.username) {
c0a81592 2914 if (ssh_get_line && !ssh_getline_pw_only) {
32874aea 2915 if (!ssh_get_line("login as: ",
51470298 2916 s->username, sizeof(s->username), FALSE)) {
32874aea 2917 /*
2918 * get_line failed to get a username.
2919 * Terminate.
2920 */
2921 logevent("No username provided. Abandoning session.");
3bb2f322 2922 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 2923 crStop(1);
32874aea 2924 }
2925 } else {
51470298 2926 int ret; /* need not be kept over crReturn */
2927 c_write_str(ssh, "login as: ");
2928 ssh->send_ok = 1;
0405e71f 2929
51470298 2930 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
0405e71f 2931 do {
ff3187f6 2932 crWaitUntil(!pktin);
51470298 2933 ret = process_userpass_input(ssh, in, inlen);
0405e71f 2934 } while (ret == 0);
2935 if (ret < 0)
2936 cleanup_exit(0);
51470298 2937 c_write_str(ssh, "\r\n");
32874aea 2938 }
2939 } else {
86916870 2940 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
51470298 2941 s->username[sizeof(s->username)-1] = '\0';
374330e2 2942 }
fb09bf1c 2943
51470298 2944 send_packet(ssh, SSH1_CMSG_USER, PKT_STR, s->username, PKT_END);
c5e9c988 2945 {
51470298 2946 char userlog[22 + sizeof(s->username)];
2947 sprintf(userlog, "Sent username \"%s\"", s->username);
c5e9c988 2948 logevent(userlog);
32874aea 2949 if (flags & FLAG_INTERACTIVE &&
2950 (!((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)))) {
3c8e959b 2951 strcat(userlog, "\r\n");
51470298 2952 c_write_str(ssh, userlog);
3c8e959b 2953 }
c5e9c988 2954 }
374330e2 2955 }
2956
ff3187f6 2957 crWaitUntil(pktin);
374330e2 2958
51470298 2959 if ((ssh->remote_bugs & BUG_CHOKES_ON_RSA)) {
0df73905 2960 /* We must not attempt PK auth. Pretend we've already tried it. */
51470298 2961 s->tried_publickey = s->tried_agent = 1;
0df73905 2962 } else {
51470298 2963 s->tried_publickey = s->tried_agent = 0;
0df73905 2964 }
51470298 2965 s->tis_auth_refused = s->ccard_auth_refused = 0;
86916870 2966 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
9a30e26b 2967 if (!filename_is_null(ssh->cfg.keyfile)) {
2968 if (!rsakey_pubblob(&ssh->cfg.keyfile,
222d54dc 2969 &s->publickey_blob, &s->publickey_bloblen, NULL))
51470298 2970 s->publickey_blob = NULL;
396778f1 2971 } else
51470298 2972 s->publickey_blob = NULL;
7cca0d81 2973
ff3187f6 2974 while (pktin->type == SSH1_SMSG_FAILURE) {
51470298 2975 s->pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
614a20a0 2976
51470298 2977 if (agent_exists() && !s->tried_agent) {
32874aea 2978 /*
2979 * Attempt RSA authentication using Pageant.
2980 */
32874aea 2981 void *r;
2982
51470298 2983 s->authed = FALSE;
2984 s->tried_agent = 1;
32874aea 2985 logevent("Pageant is running. Requesting keys.");
2986
2987 /* Request the keys held by the agent. */
51470298 2988 PUT_32BIT(s->request, 1);
2989 s->request[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES;
839f10db 2990 if (!agent_query(s->request, 5, &r, &s->responselen,
2991 ssh_agent_callback, ssh)) {
2992 do {
2993 crReturn(0);
ff3187f6 2994 if (pktin) {
839f10db 2995 bombout(("Unexpected data from server while waiting"
2996 " for agent response"));
2997 crStop(0);
2998 }
ff3187f6 2999 } while (pktin || inlen > 0);
839f10db 3000 r = ssh->agent_response;
3001 s->responselen = ssh->agent_response_len;
3002 }
51470298 3003 s->response = (unsigned char *) r;
3004 if (s->response && s->responselen >= 5 &&
3005 s->response[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER) {
3006 s->p = s->response + 5;
3007 s->nkeys = GET_32BIT(s->p);
3008 s->p += 4;
32874aea 3009 {
3010 char buf[64];
51470298 3011 sprintf(buf, "Pageant has %d SSH1 keys", s->nkeys);
32874aea 3012 logevent(buf);
3013 }
51470298 3014 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
32874aea 3015 {
3016 char buf[64];
51470298 3017 sprintf(buf, "Trying Pageant key #%d", s->keyi);
32874aea 3018 logevent(buf);
3019 }
51470298 3020 if (s->publickey_blob &&
3021 !memcmp(s->p, s->publickey_blob,
3022 s->publickey_bloblen)) {
396778f1 3023 logevent("This key matches configured key file");
51470298 3024 s->tried_publickey = 1;
396778f1 3025 }
51470298 3026 s->p += 4;
0016d70b 3027 {
3028 int n, ok = FALSE;
3029 do { /* do while (0) to make breaking easy */
3030 n = ssh1_read_bignum
3031 (s->p, s->responselen-(s->p-s->response),
3032 &s->key.exponent);
3033 if (n < 0)
3034 break;
3035 s->p += n;
3036 n = ssh1_read_bignum
3037 (s->p, s->responselen-(s->p-s->response),
3038 &s->key.modulus);
3039 if (n < 0)
3040 break;
3041 s->p += n;
3042 if (s->responselen - (s->p-s->response) < 4)
3043 break;
3044 s->commentlen = GET_32BIT(s->p);
3045 s->p += 4;
3046 if (s->responselen - (s->p-s->response) <
3047 s->commentlen)
3048 break;
3049 s->commentp = (char *)s->p;
3050 s->p += s->commentlen;
3051 ok = TRUE;
3052 } while (0);
3053 if (!ok) {
3054 logevent("Pageant key list packet was truncated");
3055 break;
3056 }
3057 }
51470298 3058 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
3059 PKT_BIGNUM, s->key.modulus, PKT_END);
ff3187f6 3060 crWaitUntil(pktin);
3061 if (pktin->type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
32874aea 3062 logevent("Key refused");
3063 continue;
3064 }
3065 logevent("Received RSA challenge");
ff3187f6 3066 if ((s->challenge = ssh1_pkt_getmp(pktin)) == NULL) {
0016d70b 3067 bombout(("Server's RSA challenge was badly formatted"));
3068 crStop(0);
3069 }
3070
32874aea 3071 {
3072 char *agentreq, *q, *ret;
2d466ffd 3073 void *vret;
32874aea 3074 int len, retlen;
3075 len = 1 + 4; /* message type, bit count */
51470298 3076 len += ssh1_bignum_length(s->key.exponent);
3077 len += ssh1_bignum_length(s->key.modulus);
3078 len += ssh1_bignum_length(s->challenge);
32874aea 3079 len += 16; /* session id */
3080 len += 4; /* response format */
3d88e64d 3081 agentreq = snewn(4 + len, char);
32874aea 3082 PUT_32BIT(agentreq, len);
3083 q = agentreq + 4;
3084 *q++ = SSH1_AGENTC_RSA_CHALLENGE;
51470298 3085 PUT_32BIT(q, bignum_bitcount(s->key.modulus));
32874aea 3086 q += 4;
51470298 3087 q += ssh1_write_bignum(q, s->key.exponent);
3088 q += ssh1_write_bignum(q, s->key.modulus);
3089 q += ssh1_write_bignum(q, s->challenge);
3090 memcpy(q, s->session_id, 16);
32874aea 3091 q += 16;
3092 PUT_32BIT(q, 1); /* response format */
839f10db 3093 if (!agent_query(agentreq, len + 4, &vret, &retlen,
3094 ssh_agent_callback, ssh)) {
3095 sfree(agentreq);
3096 do {
3097 crReturn(0);
ff3187f6 3098 if (pktin) {
839f10db 3099 bombout(("Unexpected data from server"
3100 " while waiting for agent"
3101 " response"));
3102 crStop(0);
3103 }
ff3187f6 3104 } while (pktin || inlen > 0);
839f10db 3105 vret = ssh->agent_response;
3106 retlen = ssh->agent_response_len;
3107 } else
3108 sfree(agentreq);
2d466ffd 3109 ret = vret;
32874aea 3110 if (ret) {
3111 if (ret[4] == SSH1_AGENT_RSA_RESPONSE) {
3112 logevent("Sending Pageant's response");
51470298 3113 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
32874aea 3114 PKT_DATA, ret + 5, 16,
3115 PKT_END);
3116 sfree(ret);
ff3187f6 3117 crWaitUntil(pktin);
3118 if (pktin->type == SSH1_SMSG_SUCCESS) {
32874aea 3119 logevent
3120 ("Pageant's response accepted");
3121 if (flags & FLAG_VERBOSE) {
51470298 3122 c_write_str(ssh, "Authenticated using"
3123 " RSA key \"");
3124 c_write(ssh, s->commentp,
3125 s->commentlen);
3126 c_write_str(ssh, "\" from agent\r\n");
32874aea 3127 }
51470298 3128 s->authed = TRUE;
32874aea 3129 } else
3130 logevent
3131 ("Pageant's response not accepted");
3132 } else {
3133 logevent
3134 ("Pageant failed to answer challenge");
3135 sfree(ret);
3136 }
3137 } else {
3138 logevent("No reply received from Pageant");
3139 }
3140 }
51470298 3141 freebn(s->key.exponent);
3142 freebn(s->key.modulus);
3143 freebn(s->challenge);
3144 if (s->authed)
32874aea 3145 break;
3146 }
29b1d0b3 3147 sfree(s->response);
32874aea 3148 }
51470298 3149 if (s->authed)
32874aea 3150 break;
3151 }
9a30e26b 3152 if (!filename_is_null(ssh->cfg.keyfile) && !s->tried_publickey)
51470298 3153 s->pwpkt_type = SSH1_CMSG_AUTH_RSA;
32874aea 3154
86916870 3155 if (ssh->cfg.try_tis_auth &&
51470298 3156 (s->supported_auths_mask & (1 << SSH1_AUTH_TIS)) &&
3157 !s->tis_auth_refused) {
3158 s->pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
32874aea 3159 logevent("Requested TIS authentication");
51470298 3160 send_packet(ssh, SSH1_CMSG_AUTH_TIS, PKT_END);
ff3187f6 3161 crWaitUntil(pktin);
3162 if (pktin->type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
32874aea 3163 logevent("TIS authentication declined");
3164 if (flags & FLAG_INTERACTIVE)
51470298 3165 c_write_str(ssh, "TIS authentication refused.\r\n");
3166 s->tis_auth_refused = 1;
614a20a0 3167 continue;
32874aea 3168 } else {
0016d70b 3169 char *challenge;
3170 int challengelen;
3171
ff3187f6 3172 ssh_pkt_getstring(pktin, &challenge, &challengelen);
0016d70b 3173 if (!challenge) {
3174 bombout(("TIS challenge packet was badly formed"));
3175 crStop(0);
3176 }
32874aea 3177 logevent("Received TIS challenge");
51470298 3178 if (challengelen > sizeof(s->prompt) - 1)
3179 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
0016d70b 3180 memcpy(s->prompt, challenge, challengelen);
614a20a0 3181 /* Prompt heuristic comes from OpenSSH */
51470298 3182 strncpy(s->prompt + challengelen,
3183 memchr(s->prompt, '\n', challengelen) ?
614a20a0 3184 "": "\r\nResponse: ",
51470298 3185 (sizeof s->prompt) - challengelen);
3186 s->prompt[(sizeof s->prompt) - 1] = '\0';
32874aea 3187 }
3188 }
86916870 3189 if (ssh->cfg.try_tis_auth &&
51470298 3190 (s->supported_auths_mask & (1 << SSH1_AUTH_CCARD)) &&
3191 !s->ccard_auth_refused) {
3192 s->pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
32874aea 3193 logevent("Requested CryptoCard authentication");
51470298 3194 send_packet(ssh, SSH1_CMSG_AUTH_CCARD, PKT_END);
ff3187f6 3195 crWaitUntil(pktin);
3196 if (pktin->type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
32874aea 3197 logevent("CryptoCard authentication declined");
51470298 3198 c_write_str(ssh, "CryptoCard authentication refused.\r\n");
3199 s->ccard_auth_refused = 1;
614a20a0 3200 continue;
32874aea 3201 } else {
0016d70b 3202 char *challenge;
3203 int challengelen;
3204
ff3187f6 3205 ssh_pkt_getstring(pktin, &challenge, &challengelen);
0016d70b 3206 if (!challenge) {
3207 bombout(("CryptoCard challenge packet was badly formed"));
3208 crStop(0);
3209 }
32874aea 3210 logevent("Received CryptoCard challenge");
51470298 3211 if (challengelen > sizeof(s->prompt) - 1)
3212 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
0016d70b 3213 memcpy(s->prompt, challenge, challengelen);
51470298 3214 strncpy(s->prompt + challengelen,
3215 memchr(s->prompt, '\n', challengelen) ?
614a20a0 3216 "" : "\r\nResponse: ",
51470298 3217 sizeof(s->prompt) - challengelen);
3218 s->prompt[sizeof(s->prompt) - 1] = '\0';
32874aea 3219 }
3220 }
51470298 3221 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
3222 sprintf(s->prompt, "%.90s@%.90s's password: ",
3223 s->username, ssh->savedhost);
32874aea 3224 }
51470298 3225 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
32874aea 3226 char *comment = NULL;
231ee168 3227 int type;
3228 char msgbuf[256];
32874aea 3229 if (flags & FLAG_VERBOSE)
51470298 3230 c_write_str(ssh, "Trying public key authentication.\r\n");
6c6d9ed9 3231 logeventf(ssh, "Trying public key \"%s\"",
3232 filename_to_str(&ssh->cfg.keyfile));
9a30e26b 3233 type = key_type(&ssh->cfg.keyfile);
231ee168 3234 if (type != SSH_KEYTYPE_SSH1) {
3235 sprintf(msgbuf, "Key is of wrong type (%s)",
3236 key_type_to_str(type));
3237 logevent(msgbuf);
51470298 3238 c_write_str(ssh, msgbuf);
3239 c_write_str(ssh, "\r\n");
3240 s->tried_publickey = 1;
231ee168 3241 continue;
3242 }
9a30e26b 3243 if (!rsakey_encrypted(&ssh->cfg.keyfile, &comment)) {
32874aea 3244 if (flags & FLAG_VERBOSE)
51470298 3245 c_write_str(ssh, "No passphrase required.\r\n");
32874aea 3246 goto tryauth;
3247 }
51470298 3248 sprintf(s->prompt, "Passphrase for key \"%.100s\": ", comment);
32874aea 3249 sfree(comment);
3250 }
a52f067e 3251
614a20a0 3252 /*
3253 * Show password prompt, having first obtained it via a TIS
3254 * or CryptoCard exchange if we're doing TIS or CryptoCard
3255 * authentication.
3256 */
fa17a66e 3257 if (ssh_get_line) {
51470298 3258 if (!ssh_get_line(s->prompt, s->password,
3259 sizeof(s->password), TRUE)) {
32874aea 3260 /*
3261 * get_line failed to get a password (for example
3262 * because one was supplied on the command line
3263 * which has already failed to work). Terminate.
3264 */
51470298 3265 send_packet(ssh, SSH1_MSG_DISCONNECT,
2bc6a386 3266 PKT_STR, "No more passwords available to try",
3267 PKT_END);
247308b5 3268 logevent("Unable to authenticate");
a8327734 3269 connection_fatal(ssh->frontend, "Unable to authenticate");
3bb2f322 3270 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 3271 crStop(1);
32874aea 3272 }
fb09bf1c 3273 } else {
614a20a0 3274 /* Prompt may have come from server. We've munged it a bit, so
3275 * we know it to be zero-terminated at least once. */
51470298 3276 int ret; /* need not be saved over crReturn */
3277 c_write_untrusted(ssh, s->prompt, strlen(s->prompt));
3278 s->pos = 0;
0405e71f 3279
51470298 3280 setup_userpass_input(ssh, s->password, sizeof(s->password), 0);
0405e71f 3281 do {
ff3187f6 3282 crWaitUntil(!pktin);
51470298 3283 ret = process_userpass_input(ssh, in, inlen);
0405e71f 3284 } while (ret == 0);
3285 if (ret < 0)
3286 cleanup_exit(0);
51470298 3287 c_write_str(ssh, "\r\n");
32874aea 3288 }
3289
3290 tryauth:
51470298 3291 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
32874aea 3292 /*
3293 * Try public key authentication with the specified
3294 * key file.
3295 */
51470298 3296 s->tried_publickey = 1;
3297
3298 {
222d54dc 3299 const char *error = NULL;
3300 int ret = loadrsakey(&ssh->cfg.keyfile, &s->key, s->password,
3301 &error);
51470298 3302 if (ret == 0) {
3303 c_write_str(ssh, "Couldn't load private key from ");
9fab77dc 3304 c_write_str(ssh, filename_to_str(&ssh->cfg.keyfile));
222d54dc 3305 c_write_str(ssh, " (");
3306 c_write_str(ssh, error);
3307 c_write_str(ssh, ").\r\n");
51470298 3308 continue; /* go and try password */
3309 }
3310 if (ret == -1) {
3311 c_write_str(ssh, "Wrong passphrase.\r\n");
3312 s->tried_publickey = 0;
3313 continue; /* try again */
3314 }
32874aea 3315 }
3316
3317 /*
3318 * Send a public key attempt.
3319 */
51470298 3320 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
3321 PKT_BIGNUM, s->key.modulus, PKT_END);
32874aea 3322
ff3187f6 3323 crWaitUntil(pktin);
3324 if (pktin->type == SSH1_SMSG_FAILURE) {
51470298 3325 c_write_str(ssh, "Server refused our public key.\r\n");
32874aea 3326 continue; /* go and try password */
3327 }
ff3187f6 3328 if (pktin->type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
6b5cf8b4 3329 bombout(("Bizarre response to offer of public key"));
7ffdbc1a 3330 crStop(0);
32874aea 3331 }
32874aea 3332
51470298 3333 {
3334 int i;
3335 unsigned char buffer[32];
3336 Bignum challenge, response;
3337
ff3187f6 3338 if ((challenge = ssh1_pkt_getmp(pktin)) == NULL) {
0016d70b 3339 bombout(("Server's RSA challenge was badly formatted"));
3340 crStop(0);
3341 }
51470298 3342 response = rsadecrypt(challenge, &s->key);
3343 freebn(s->key.private_exponent);/* burn the evidence */
32874aea 3344
51470298 3345 for (i = 0; i < 32; i++) {
3346 buffer[i] = bignum_byte(response, 31 - i);
3347 }
3348
3349 MD5Init(&md5c);
3350 MD5Update(&md5c, buffer, 32);
3351 MD5Update(&md5c, s->session_id, 16);
3352 MD5Final(buffer, &md5c);
32874aea 3353
51470298 3354 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
3355 PKT_DATA, buffer, 16, PKT_END);
3356
3357 freebn(challenge);
3358 freebn(response);
3359 }
32874aea 3360
ff3187f6 3361 crWaitUntil(pktin);
3362 if (pktin->type == SSH1_SMSG_FAILURE) {
32874aea 3363 if (flags & FLAG_VERBOSE)
51470298 3364 c_write_str(ssh, "Failed to authenticate with"
3365 " our public key.\r\n");
32874aea 3366 continue; /* go and try password */
ff3187f6 3367 } else if (pktin->type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 3368 bombout(("Bizarre response to RSA authentication response"));
7ffdbc1a 3369 crStop(0);
32874aea 3370 }
3371
3372 break; /* we're through! */
3373 } else {
51470298 3374 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
32874aea 3375 /*
3376 * Defence against traffic analysis: we send a
3377 * whole bunch of packets containing strings of
3378 * different lengths. One of these strings is the
3379 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3380 * The others are all random data in
3381 * SSH1_MSG_IGNORE packets. This way a passive
3382 * listener can't tell which is the password, and
3383 * hence can't deduce the password length.
3384 *
3385 * Anybody with a password length greater than 16
3386 * bytes is going to have enough entropy in their
3387 * password that a listener won't find it _that_
3388 * much help to know how long it is. So what we'll
3389 * do is:
3390 *
3391 * - if password length < 16, we send 15 packets
3392 * containing string lengths 1 through 15
3393 *
3394 * - otherwise, we let N be the nearest multiple
3395 * of 8 below the password length, and send 8
3396 * packets containing string lengths N through
3397 * N+7. This won't obscure the order of
3398 * magnitude of the password length, but it will
3399 * introduce a bit of extra uncertainty.
3400 *
3401 * A few servers (the old 1.2.18 through 1.2.22)
3402 * can't deal with SSH1_MSG_IGNORE. For these
3403 * servers, we need an alternative defence. We make
3404 * use of the fact that the password is interpreted
3405 * as a C string: so we can append a NUL, then some
3406 * random data.
bd358db1 3407 *
3408 * One server (a Cisco one) can deal with neither
3409 * SSH1_MSG_IGNORE _nor_ a padded password string.
3410 * For this server we are left with no defences
3411 * against password length sniffing.
32874aea 3412 */
51470298 3413 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE)) {
b17c8428 3414 /*
3415 * The server can deal with SSH1_MSG_IGNORE, so
3416 * we can use the primary defence.
3417 */
32874aea 3418 int bottom, top, pwlen, i;
3419 char *randomstr;
3420
51470298 3421 pwlen = strlen(s->password);
32874aea 3422 if (pwlen < 16) {
3423 bottom = 0; /* zero length passwords are OK! :-) */
3424 top = 15;
3425 } else {
3426 bottom = pwlen & ~7;
3427 top = bottom + 7;
3428 }
3429
3430 assert(pwlen >= bottom && pwlen <= top);
3431
3d88e64d 3432 randomstr = snewn(top + 1, char);
32874aea 3433
3434 for (i = bottom; i <= top; i++) {
9a10ecf4 3435 if (i == pwlen) {
51470298 3436 defer_packet(ssh, s->pwpkt_type,
9a10ecf4 3437 PKTT_PASSWORD, PKT_STR, s->password,
3438 PKTT_OTHER, PKT_END);
3439 } else {
32874aea 3440 for (j = 0; j < i; j++) {
3441 do {
3442 randomstr[j] = random_byte();
3443 } while (randomstr[j] == '\0');
3444 }
3445 randomstr[i] = '\0';
51470298 3446 defer_packet(ssh, SSH1_MSG_IGNORE,
32874aea 3447 PKT_STR, randomstr, PKT_END);
3448 }
3449 }
bd358db1 3450 logevent("Sending password with camouflage packets");
51470298 3451 ssh_pkt_defersend(ssh);
679539d7 3452 sfree(randomstr);
bd358db1 3453 }
51470298 3454 else if (!(ssh->remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
b17c8428 3455 /*
3456 * The server can't deal with SSH1_MSG_IGNORE
3457 * but can deal with padded passwords, so we
3458 * can use the secondary defence.
3459 */
bd358db1 3460 char string[64];
51470298 3461 char *ss;
bd358db1 3462 int len;
3463
51470298 3464 len = strlen(s->password);
bd358db1 3465 if (len < sizeof(string)) {
51470298 3466 ss = string;
3467 strcpy(string, s->password);
bd358db1 3468 len++; /* cover the zero byte */
3469 while (len < sizeof(string)) {
3470 string[len++] = (char) random_byte();
3471 }
3472 } else {
51470298 3473 ss = s->password;
bd358db1 3474 }
3475 logevent("Sending length-padded password");
9a10ecf4 3476 send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
3477 PKT_INT, len, PKT_DATA, ss, len,
3478 PKTT_OTHER, PKT_END);
bd358db1 3479 } else {
3480 /*
3481 * The server has _both_
3482 * BUG_CHOKES_ON_SSH1_IGNORE and
3483 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3484 * therefore nothing we can do.
3485 */
3486 int len;
51470298 3487 len = strlen(s->password);
bd358db1 3488 logevent("Sending unpadded password");
9a10ecf4 3489 send_packet(ssh, s->pwpkt_type,
3490 PKTT_PASSWORD, PKT_INT, len,
3491 PKT_DATA, s->password, len,
3492 PKTT_OTHER, PKT_END);
32874aea 3493 }
3494 } else {
9a10ecf4 3495 send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
3496 PKT_STR, s->password, PKTT_OTHER, PKT_END);
32874aea 3497 }
3498 }
c5e9c988 3499 logevent("Sent password");
51470298 3500 memset(s->password, 0, strlen(s->password));
ff3187f6 3501 crWaitUntil(pktin);
3502 if (pktin->type == SSH1_SMSG_FAILURE) {
32874aea 3503 if (flags & FLAG_VERBOSE)
51470298 3504 c_write_str(ssh, "Access denied\r\n");
c5e9c988 3505 logevent("Authentication refused");
ff3187f6 3506 } else if (pktin->type != SSH1_SMSG_SUCCESS) {
3507 bombout(("Strange packet received, type %d", pktin->type));
7ffdbc1a 3508 crStop(0);
374330e2 3509 }
3510 }
3511
c5e9c988 3512 logevent("Authentication successful");
3513
fb09bf1c 3514 crFinish(1);
3515}
3516
32874aea 3517void sshfwd_close(struct ssh_channel *c)
3518{
51470298 3519 Ssh ssh = c->ssh;
3520
36f94d1f 3521 if (ssh->state != SSH_STATE_SESSION) {
3522 assert(ssh->state == SSH_STATE_CLOSED);
3523 return;
3524 }
3525
80e48603 3526 if (c && !c->closes) {
4ed34d25 3527 /*
3528 * If the channel's remoteid is -1, we have sent
3529 * CHANNEL_OPEN for this channel, but it hasn't even been
3530 * acknowledged by the server. So we must set a close flag
3531 * on it now, and then when the server acks the channel
3532 * open, we can close it then.
3533 */
36cac739 3534 if (((int)c->remoteid) != -1) {
51470298 3535 if (ssh->version == 1) {
3536 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid,
4ed34d25 3537 PKT_END);
3538 } else {
ff3187f6 3539 struct Packet *pktout;
3540 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
3541 ssh2_pkt_adduint32(pktout, c->remoteid);
3542 ssh2_pkt_send(ssh, pktout);
4ed34d25 3543 }
32874aea 3544 }
0357890f 3545 c->closes = 1; /* sent MSG_CLOSE */
32874aea 3546 if (c->type == CHAN_X11) {
3547 c->u.x11.s = NULL;
d74d141c 3548 logevent("Forwarded X11 connection terminated");
4ed34d25 3549 } else if (c->type == CHAN_SOCKDATA ||
3550 c->type == CHAN_SOCKDATA_DORMANT) {
d74d141c 3551 c->u.pfd.s = NULL;
3552 logevent("Forwarded port closed");
32874aea 3553 }
3554 }
3555}
3556
5471d09a 3557int sshfwd_write(struct ssh_channel *c, char *buf, int len)
32874aea 3558{
51470298 3559 Ssh ssh = c->ssh;
3560
36f94d1f 3561 if (ssh->state != SSH_STATE_SESSION) {
3562 assert(ssh->state == SSH_STATE_CLOSED);
3563 return 0;
3564 }
3565
51470298 3566 if (ssh->version == 1) {
3567 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
32874aea 3568 PKT_INT, c->remoteid,
9a10ecf4 3569 PKTT_DATA,
3570 PKT_INT, len, PKT_DATA, buf, len,
3571 PKTT_OTHER, PKT_END);
5471d09a 3572 /*
3573 * In SSH1 we can return 0 here - implying that forwarded
3574 * connections are never individually throttled - because
3575 * the only circumstance that can cause throttling will be
3576 * the whole SSH connection backing up, in which case
3577 * _everything_ will be throttled as a whole.
3578 */
3579 return 0;
783415f8 3580 } else {
32874aea 3581 ssh2_add_channel_data(c, buf, len);
5471d09a 3582 return ssh2_try_send(c);
3583 }
3584}
3585
3586void sshfwd_unthrottle(struct ssh_channel *c, int bufsize)
3587{
51470298 3588 Ssh ssh = c->ssh;
3589
36f94d1f 3590 if (ssh->state != SSH_STATE_SESSION) {
3591 assert(ssh->state == SSH_STATE_CLOSED);
3592 return;
3593 }
3594
51470298 3595 if (ssh->version == 1) {
5471d09a 3596 if (c->v.v1.throttling && bufsize < SSH1_BUFFER_LIMIT) {
3597 c->v.v1.throttling = 0;
51470298 3598 ssh1_throttle(ssh, -1);
5471d09a 3599 }
3600 } else {
3601 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
783415f8 3602 }
9c964e85 3603}
3604
06fadff5 3605static void ssh_queueing_handler(Ssh ssh, struct Packet *pktin)
3606{
3607 struct queued_handler *qh = ssh->qhead;
3608
3609 assert(qh != NULL);
3610
3611 assert(pktin->type == qh->msg1 || pktin->type == qh->msg2);
3612
3613 if (qh->msg1 > 0) {
3614 assert(ssh->packet_dispatch[qh->msg1] == ssh_queueing_handler);
3615 ssh->packet_dispatch[qh->msg1] = NULL;
3616 }
3617 if (qh->msg2 > 0) {
3618 assert(ssh->packet_dispatch[qh->msg2] == ssh_queueing_handler);
3619 ssh->packet_dispatch[qh->msg2] = NULL;
3620 }
3621
3622 if (qh->next) {
3623 ssh->qhead = qh->next;
3624
3625 if (ssh->qhead->msg1 > 0) {
3626 assert(ssh->packet_dispatch[ssh->qhead->msg1] == NULL);
3627 ssh->packet_dispatch[ssh->qhead->msg1] = ssh_queueing_handler;
3628 }
3629 if (ssh->qhead->msg2 > 0) {
3630 assert(ssh->packet_dispatch[ssh->qhead->msg2] == NULL);
3631 ssh->packet_dispatch[ssh->qhead->msg2] = ssh_queueing_handler;
3632 }
3633 } else {
3634 ssh->qhead = ssh->qtail = NULL;
3635 ssh->packet_dispatch[pktin->type] = NULL;
3636 }
3637
3638 qh->handler(ssh, pktin, qh->ctx);
3639
3640 sfree(qh);
3641}
3642
3643static void ssh_queue_handler(Ssh ssh, int msg1, int msg2,
3644 chandler_fn_t handler, void *ctx)
3645{
3646 struct queued_handler *qh;
3647
3648 qh = snew(struct queued_handler);
3649 qh->msg1 = msg1;
3650 qh->msg2 = msg2;
3651 qh->handler = handler;
3652 qh->ctx = ctx;
3653 qh->next = NULL;
3654
3655 if (ssh->qtail == NULL) {
3656 ssh->qhead = qh;
3657
3658 if (qh->msg1 > 0) {
3659 assert(ssh->packet_dispatch[qh->msg1] == NULL);
3660 ssh->packet_dispatch[qh->msg1] = ssh_queueing_handler;
3661 }
3662 if (qh->msg2 > 0) {
3663 assert(ssh->packet_dispatch[qh->msg2] == NULL);
3664 ssh->packet_dispatch[qh->msg2] = ssh_queueing_handler;
3665 }
3666 } else {
3667 ssh->qtail->next = qh;
3668 }
3669 ssh->qtail = qh;
3670}
3671
3672static void ssh_rportfwd_succfail(Ssh ssh, struct Packet *pktin, void *ctx)
3673{
3674 struct ssh_rportfwd *rpf, *pf = (struct ssh_rportfwd *)ctx;
3675
3676 if (pktin->type == (ssh->version == 1 ? SSH1_SMSG_SUCCESS :
3677 SSH2_MSG_REQUEST_SUCCESS)) {
3678 logeventf(ssh, "Remote port forwarding from %s enabled",
3679 pf->sportdesc);
3680 } else {
3681 logeventf(ssh, "Remote port forwarding from %s refused",
3682 pf->sportdesc);
3683
3684 rpf = del234(ssh->rportfwds, pf);
3685 assert(rpf == pf);
fda2feb1 3686 free_rportfwd(pf);
06fadff5 3687 }
3688}
3689
3690static void ssh_setup_portfwd(Ssh ssh, const Config *cfg)
3691{
84328ddb 3692 const char *portfwd_strptr = cfg->portfwd;
3693 struct ssh_portfwd *epf;
3694 int i;
06fadff5 3695
fda2feb1 3696 if (!ssh->portfwds) {
3697 ssh->portfwds = newtree234(ssh_portcmp);
3698 } else {
3699 /*
3700 * Go through the existing port forwardings and tag them
84328ddb 3701 * with status==DESTROY. Any that we want to keep will be
3702 * re-enabled (status==KEEP) as we go through the
3703 * configuration and find out which bits are the same as
3704 * they were before.
fda2feb1 3705 */
3706 struct ssh_portfwd *epf;
3707 int i;
3708 for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
84328ddb 3709 epf->status = DESTROY;
fda2feb1 3710 }
3711
06fadff5 3712 while (*portfwd_strptr) {
84328ddb 3713 char address_family, type;
3714 int sport,dport,sserv,dserv;
3715 char sports[256], dports[256], saddr[256], host[256];
3716 int n;
3717
05581745 3718 address_family = 'A';
3719 type = 'L';
84328ddb 3720 if (*portfwd_strptr == 'A' ||
3721 *portfwd_strptr == '4' ||
3722 *portfwd_strptr == '6')
3723 address_family = *portfwd_strptr++;
3724 if (*portfwd_strptr == 'L' ||
3725 *portfwd_strptr == 'R' ||
3726 *portfwd_strptr == 'D')
3727 type = *portfwd_strptr++;
05581745 3728
06fadff5 3729 saddr[0] = '\0';
05581745 3730
06fadff5 3731 n = 0;
3732 while (*portfwd_strptr && *portfwd_strptr != '\t') {
3733 if (*portfwd_strptr == ':') {
3734 /*
3735 * We've seen a colon in the middle of the
3736 * source port number. This means that
3737 * everything we've seen until now is the
3738 * source _address_, so we'll move it into
3739 * saddr and start sports from the beginning
3740 * again.
3741 */
3742 portfwd_strptr++;
3743 sports[n] = '\0';
3744 if (ssh->version == 1 && type == 'R') {
3745 logeventf(ssh, "SSH1 cannot handle remote source address "
3746 "spec \"%s\"; ignoring", sports);
3747 } else
3748 strcpy(saddr, sports);
3749 n = 0;
3750 }
3751 if (n < 255) sports[n++] = *portfwd_strptr++;
3752 }
3753 sports[n] = 0;
3754 if (type != 'D') {
3755 if (*portfwd_strptr == '\t')
3756 portfwd_strptr++;
3757 n = 0;
3758 while (*portfwd_strptr && *portfwd_strptr != ':') {
3759 if (n < 255) host[n++] = *portfwd_strptr++;
3760 }
3761 host[n] = 0;
3762 if (*portfwd_strptr == ':')
3763 portfwd_strptr++;
3764 n = 0;
3765 while (*portfwd_strptr) {
3766 if (n < 255) dports[n++] = *portfwd_strptr++;
3767 }
3768 dports[n] = 0;
3769 portfwd_strptr++;
3770 dport = atoi(dports);
3771 dserv = 0;
3772 if (dport == 0) {
3773 dserv = 1;
3774 dport = net_service_lookup(dports);
3775 if (!dport) {
3776 logeventf(ssh, "Service lookup failed for destination"
3777 " port \"%s\"", dports);
3778 }
3779 }
3780 } else {
3781 while (*portfwd_strptr) portfwd_strptr++;
3782 dport = dserv = -1;
3783 portfwd_strptr++; /* eat the NUL and move to next one */
3784 }
3785 sport = atoi(sports);
3786 sserv = 0;
3787 if (sport == 0) {
3788 sserv = 1;
3789 sport = net_service_lookup(sports);
3790 if (!sport) {
3791 logeventf(ssh, "Service lookup failed for source"
3792 " port \"%s\"", sports);
3793 }
3794 }
3795 if (sport && dport) {
3796 /* Set up a description of the source port. */
fda2feb1 3797 struct ssh_portfwd *pfrec, *epfrec;
fda2feb1 3798
3799 pfrec = snew(struct ssh_portfwd);
3800 pfrec->type = type;
3801 pfrec->saddr = *saddr ? dupstr(saddr) : NULL;
3fe92132 3802 pfrec->sserv = sserv ? dupstr(sports) : NULL;
fda2feb1 3803 pfrec->sport = sport;
84328ddb 3804 pfrec->daddr = *host ? dupstr(host) : NULL;
3fe92132 3805 pfrec->dserv = dserv ? dupstr(dports) : NULL;
fda2feb1 3806 pfrec->dport = dport;
3807 pfrec->local = NULL;
3808 pfrec->remote = NULL;
05581745 3809 pfrec->addressfamily = (address_family == '4' ? ADDRTYPE_IPV4 :
3810 address_family == '6' ? ADDRTYPE_IPV6 :
3811 ADDRTYPE_UNSPEC);
fda2feb1 3812
3813 epfrec = add234(ssh->portfwds, pfrec);
3814 if (epfrec != pfrec) {
3815 /*
3816 * We already have a port forwarding with precisely
3817 * these parameters. Hence, no need to do anything;
84328ddb 3818 * simply tag the existing one as KEEP.
fda2feb1 3819 */
84328ddb 3820 epfrec->status = KEEP;
fda2feb1 3821 free_portfwd(pfrec);
84328ddb 3822 } else {
3823 pfrec->status = CREATE;
3824 }
3825 }
3826 }
3827
3828 /*
3829 * Now go through and destroy any port forwardings which were
3830 * not re-enabled.
3831 */
3832 for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
3833 if (epf->status == DESTROY) {
3834 char *message;
3835
3836 message = dupprintf("%s port forwarding from %s%s%d",
3837 epf->type == 'L' ? "local" :
3838 epf->type == 'R' ? "remote" : "dynamic",
3839 epf->saddr ? epf->saddr : "",
3840 epf->saddr ? ":" : "",
3841 epf->sport);
3842
3843 if (epf->type != 'D') {
3844 char *msg2 = dupprintf("%s to %s:%d", message,
3845 epf->daddr, epf->dport);
3846 sfree(message);
3847 message = msg2;
3848 }
3849
3850 logeventf(ssh, "Cancelling %s", message);
3851 sfree(message);
3852
3853 if (epf->remote) {
3854 struct ssh_rportfwd *rpf = epf->remote;
3855 struct Packet *pktout;
3856
3857 /*
3858 * Cancel the port forwarding at the server
3859 * end.
3860 */
3861 if (ssh->version == 1) {
3862 /*
3863 * We cannot cancel listening ports on the
3864 * server side in SSH1! There's no message
3865 * to support it. Instead, we simply remove
3866 * the rportfwd record from the local end
3867 * so that any connections the server tries
3868 * to make on it are rejected.
3869 */
3870 } else {
3871 pktout = ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST);
3872 ssh2_pkt_addstring(pktout, "cancel-tcpip-forward");
3873 ssh2_pkt_addbool(pktout, 0);/* _don't_ want reply */
3874 if (epf->saddr) {
3875 ssh2_pkt_addstring(pktout, epf->saddr);
3876 } else if (ssh->cfg.rport_acceptall) {
3877 ssh2_pkt_addstring(pktout, "0.0.0.0");
3878 } else {
3879 ssh2_pkt_addstring(pktout, "127.0.0.1");
3880 }
3881 ssh2_pkt_adduint32(pktout, epf->sport);
3882 ssh2_pkt_send(ssh, pktout);
3883 }
3884
3885 del234(ssh->rportfwds, rpf);
3886 free_rportfwd(rpf);
3887 } else if (epf->local) {
3888 pfd_terminate(epf->local);
3889 }
3890
3891 delpos234(ssh->portfwds, i);
3892 free_portfwd(epf);
3893 i--; /* so we don't skip one in the list */
3894 }
3895
3896 /*
3897 * And finally, set up any new port forwardings (status==CREATE).
3898 */
3899 for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
3900 if (epf->status == CREATE) {
3901 char *sportdesc, *dportdesc;
3fe92132 3902 sportdesc = dupprintf("%s%s%s%s%d%s",
84328ddb 3903 epf->saddr ? epf->saddr : "",
3904 epf->saddr ? ":" : "",
3fe92132 3905 epf->sserv ? epf->sserv : "",
3906 epf->sserv ? "(" : "",
3907 epf->sport,
3908 epf->sserv ? ")" : "");
84328ddb 3909 if (epf->type == 'D') {
3910 dportdesc = NULL;
3911 } else {
3fe92132 3912 dportdesc = dupprintf("%s:%s%s%d%s",
3913 epf->daddr,
3914 epf->dserv ? epf->dserv : "",
3915 epf->dserv ? "(" : "",
3916 epf->dport,
3917 epf->dserv ? ")" : "");
84328ddb 3918 }
05581745 3919
84328ddb 3920 if (epf->type == 'L') {
3921 const char *err = pfd_addforward(epf->daddr, epf->dport,
3922 epf->saddr, epf->sport,
3923 ssh, &ssh->cfg,
3924 &epf->local,
3925 epf->addressfamily);
3926
3927 logeventf(ssh, "Local %sport %s forwarding to %s%s%s",
3928 epf->addressfamily == ADDRTYPE_IPV4 ? "IPv4 " :
3929 epf->addressfamily == ADDRTYPE_IPV6 ? "IPv6 " : "",
3930 sportdesc, dportdesc,
3931 err ? " failed: " : "", err ? err : "");
3932 } else if (epf->type == 'D') {
06fadff5 3933 const char *err = pfd_addforward(NULL, -1,
84328ddb 3934 epf->saddr, epf->sport,
3935 ssh, &ssh->cfg,
3936 &epf->local,
3937 epf->addressfamily);
3938
3939 logeventf(ssh, "Local %sport %s SOCKS dynamic forwarding%s%s",
3940 epf->addressfamily == ADDRTYPE_IPV4 ? "IPv4 " :
3941 epf->addressfamily == ADDRTYPE_IPV6 ? "IPv6 " : "",
3942 sportdesc,
3943 err ? " failed: " : "", err ? err : "");
06fadff5 3944 } else {
3945 struct ssh_rportfwd *pf;
3946
3947 /*
3948 * Ensure the remote port forwardings tree exists.
3949 */
3950 if (!ssh->rportfwds) {
3951 if (ssh->version == 1)
3952 ssh->rportfwds = newtree234(ssh_rportcmp_ssh1);
3953 else
3954 ssh->rportfwds = newtree234(ssh_rportcmp_ssh2);
3955 }
3956
3957 pf = snew(struct ssh_rportfwd);
84328ddb 3958 strncpy(pf->dhost, epf->daddr, lenof(pf->dhost)-1);
3959 pf->dhost[lenof(pf->dhost)-1] = '\0';
3960 pf->dport = epf->dport;
3961 pf->sport = epf->sport;
06fadff5 3962 if (add234(ssh->rportfwds, pf) != pf) {
3963 logeventf(ssh, "Duplicate remote port forwarding to %s:%d",
84328ddb 3964 epf->daddr, epf->dport);
06fadff5 3965 sfree(pf);
3966 } else {
3967 logeventf(ssh, "Requesting remote port %s"
84328ddb 3968 " forward to %s", sportdesc, dportdesc);
06fadff5 3969
3970 pf->sportdesc = sportdesc;
3971 sportdesc = NULL;
84328ddb 3972 epf->remote = pf;
3973 pf->pfrec = epf;
06fadff5 3974
3975 if (ssh->version == 1) {
3976 send_packet(ssh, SSH1_CMSG_PORT_FORWARD_REQUEST,
84328ddb 3977 PKT_INT, epf->sport,
3978 PKT_STR, epf->daddr,
3979 PKT_INT, epf->dport,
06fadff5 3980 PKT_END);
3981 ssh_queue_handler(ssh, SSH1_SMSG_SUCCESS,
3982 SSH1_SMSG_FAILURE,
3983 ssh_rportfwd_succfail, pf);
3984 } else {
3985 struct Packet *pktout;
3986 pktout = ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST);
3987 ssh2_pkt_addstring(pktout, "tcpip-forward");
3988 ssh2_pkt_addbool(pktout, 1);/* want reply */
84328ddb 3989 if (epf->saddr) {
3990 ssh2_pkt_addstring(pktout, epf->saddr);
06fadff5 3991 } else if (ssh->cfg.rport_acceptall) {
3992 ssh2_pkt_addstring(pktout, "0.0.0.0");
3993 } else {
3994 ssh2_pkt_addstring(pktout, "127.0.0.1");
3995 }
84328ddb 3996 ssh2_pkt_adduint32(pktout, epf->sport);
06fadff5 3997 ssh2_pkt_send(ssh, pktout);
3998
3999 ssh_queue_handler(ssh, SSH2_MSG_REQUEST_SUCCESS,
4000 SSH2_MSG_REQUEST_FAILURE,
4001 ssh_rportfwd_succfail, pf);
4002 }
4003 }
4004 }
4005 sfree(sportdesc);
84328ddb 4006 sfree(dportdesc);
06fadff5 4007 }
06fadff5 4008}
4009
51df0ab5 4010static void ssh1_smsg_stdout_stderr_data(Ssh ssh, struct Packet *pktin)
4011{
4012 char *string;
4013 int stringlen, bufsize;
4014
4015 ssh_pkt_getstring(pktin, &string, &stringlen);
4016 if (string == NULL) {
4017 bombout(("Incoming terminal data packet was badly formed"));
4018 return;
4019 }
4020
4021 bufsize = from_backend(ssh->frontend, pktin->type == SSH1_SMSG_STDERR_DATA,
4022 string, stringlen);
4023 if (!ssh->v1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
4024 ssh->v1_stdout_throttling = 1;
4025 ssh1_throttle(ssh, +1);
4026 }
4027}
4028
4029static void ssh1_smsg_x11_open(Ssh ssh, struct Packet *pktin)
4030{
4031 /* Remote side is trying to open a channel to talk to our
4032 * X-Server. Give them back a local channel number. */
4033 struct ssh_channel *c;
4034 int remoteid = ssh_pkt_getuint32(pktin);
4035
4036 logevent("Received X11 connect request");
4037 /* Refuse if X11 forwarding is disabled. */
4038 if (!ssh->X11_fwd_enabled) {
4039 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4040 PKT_INT, remoteid, PKT_END);
4041 logevent("Rejected X11 connect request");
4042 } else {
4043 c = snew(struct ssh_channel);
4044 c->ssh = ssh;
4045
4046 if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
4047 ssh->x11auth, NULL, -1, &ssh->cfg) != NULL) {
4048 logevent("Opening X11 forward connection failed");
4049 sfree(c);
4050 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4051 PKT_INT, remoteid, PKT_END);
4052 } else {
4053 logevent
4054 ("Opening X11 forward connection succeeded");
4055 c->remoteid = remoteid;
4056 c->localid = alloc_channel_id(ssh);
4057 c->closes = 0;
4058 c->v.v1.throttling = 0;
4059 c->type = CHAN_X11; /* identify channel type */
4060 add234(ssh->channels, c);
4061 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
4062 PKT_INT, c->remoteid, PKT_INT,
4063 c->localid, PKT_END);
4064 logevent("Opened X11 forward channel");
4065 }
4066 }
4067}
4068
4069static void ssh1_smsg_agent_open(Ssh ssh, struct Packet *pktin)
4070{
4071 /* Remote side is trying to open a channel to talk to our
4072 * agent. Give them back a local channel number. */
4073 struct ssh_channel *c;
4074 int remoteid = ssh_pkt_getuint32(pktin);
4075
4076 /* Refuse if agent forwarding is disabled. */
4077 if (!ssh->agentfwd_enabled) {
4078 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4079 PKT_INT, remoteid, PKT_END);
4080 } else {
4081 c = snew(struct ssh_channel);
4082 c->ssh = ssh;
4083 c->remoteid = remoteid;
4084 c->localid = alloc_channel_id(ssh);
4085 c->closes = 0;
4086 c->v.v1.throttling = 0;
4087 c->type = CHAN_AGENT; /* identify channel type */
4088 c->u.a.lensofar = 0;
4089 add234(ssh->channels, c);
4090 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
4091 PKT_INT, c->remoteid, PKT_INT, c->localid,
4092 PKT_END);
4093 }
4094}
4095
4096static void ssh1_msg_port_open(Ssh ssh, struct Packet *pktin)
4097{
4098 /* Remote side is trying to open a channel to talk to a
4099 * forwarded port. Give them back a local channel number. */
4100 struct ssh_channel *c;
05581745 4101 struct ssh_rportfwd pf, *pfp;
51df0ab5 4102 int remoteid;
4103 int hostsize, port;
4104 char *host, buf[1024];
4105 const char *e;
4106 c = snew(struct ssh_channel);
4107 c->ssh = ssh;
4108
4109 remoteid = ssh_pkt_getuint32(pktin);
4110 ssh_pkt_getstring(pktin, &host, &hostsize);
4111 port = ssh_pkt_getuint32(pktin);
4112
4113 if (hostsize >= lenof(pf.dhost))
4114 hostsize = lenof(pf.dhost)-1;
4115 memcpy(pf.dhost, host, hostsize);
4116 pf.dhost[hostsize] = '\0';
4117 pf.dport = port;
05581745 4118 pfp = find234(ssh->rportfwds, &pf, NULL);
51df0ab5 4119
05581745 4120 if (pfp == NULL) {
51df0ab5 4121 sprintf(buf, "Rejected remote port open request for %s:%d",
4122 pf.dhost, port);
4123 logevent(buf);
4124 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4125 PKT_INT, remoteid, PKT_END);
4126 } else {
4127 sprintf(buf, "Received remote port open request for %s:%d",
4128 pf.dhost, port);
4129 logevent(buf);
4130 e = pfd_newconnect(&c->u.pfd.s, pf.dhost, port,
05581745 4131 c, &ssh->cfg, pfp->pfrec->addressfamily);
51df0ab5 4132 if (e != NULL) {
4133 char buf[256];
4134 sprintf(buf, "Port open failed: %s", e);
4135 logevent(buf);
4136 sfree(c);
4137 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4138 PKT_INT, remoteid, PKT_END);
4139 } else {
4140 c->remoteid = remoteid;
4141 c->localid = alloc_channel_id(ssh);
4142 c->closes = 0;
4143 c->v.v1.throttling = 0;
4144 c->type = CHAN_SOCKDATA; /* identify channel type */
4145 add234(ssh->channels, c);
4146 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
4147 PKT_INT, c->remoteid, PKT_INT,
4148 c->localid, PKT_END);
4149 logevent("Forwarded port opened successfully");
4150 }
4151 }
4152}
4153
4154static void ssh1_msg_channel_open_confirmation(Ssh ssh, struct Packet *pktin)
4155{
4156 unsigned int remoteid = ssh_pkt_getuint32(pktin);
4157 unsigned int localid = ssh_pkt_getuint32(pktin);
4158 struct ssh_channel *c;
4159
4160 c = find234(ssh->channels, &remoteid, ssh_channelfind);
4161 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
4162 c->remoteid = localid;
4163 c->type = CHAN_SOCKDATA;
4164 c->v.v1.throttling = 0;
4165 pfd_confirm(c->u.pfd.s);
4166 }
4167
4168 if (c && c->closes) {
4169 /*
4170 * We have a pending close on this channel,
4171 * which we decided on before the server acked
4172 * the channel open. So now we know the
4173 * remoteid, we can close it again.
4174 */
4175 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE,
4176 PKT_INT, c->remoteid, PKT_END);
4177 }
4178}
4179
4180static void ssh1_msg_channel_open_failure(Ssh ssh, struct Packet *pktin)
4181{
4182 unsigned int remoteid = ssh_pkt_getuint32(pktin);
4183 struct ssh_channel *c;
4184
4185 c = find234(ssh->channels, &remoteid, ssh_channelfind);
4186 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
4187 logevent("Forwarded connection refused by server");
4188 pfd_close(c->u.pfd.s);
4189 del234(ssh->channels, c);
4190 sfree(c);
4191 }
4192}
4193
4194static void ssh1_msg_channel_close(Ssh ssh, struct Packet *pktin)
4195{
4196 /* Remote side closes a channel. */
4197 unsigned i = ssh_pkt_getuint32(pktin);
4198 struct ssh_channel *c;
4199 c = find234(ssh->channels, &i, ssh_channelfind);
4200 if (c && ((int)c->remoteid) != -1) {
4201 int closetype;
4202 closetype =
4203 (pktin->type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
4204
4205 if ((c->closes == 0) && (c->type == CHAN_X11)) {
4206 logevent("Forwarded X11 connection terminated");
4207 assert(c->u.x11.s != NULL);
4208 x11_close(c->u.x11.s);
4209 c->u.x11.s = NULL;
4210 }
4211 if ((c->closes == 0) && (c->type == CHAN_SOCKDATA)) {
4212 logevent("Forwarded port closed");
4213 assert(c->u.pfd.s != NULL);
4214 pfd_close(c->u.pfd.s);
4215 c->u.pfd.s = NULL;
4216 }
4217
4218 c->closes |= (closetype << 2); /* seen this message */
4219 if (!(c->closes & closetype)) {
4220 send_packet(ssh, pktin->type, PKT_INT, c->remoteid,
4221 PKT_END);
4222 c->closes |= closetype; /* sent it too */
4223 }
4224
4225 if (c->closes == 15) {
4226 del234(ssh->channels, c);
4227 sfree(c);
4228 }
4229 } else {
4230 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
4231 pktin->type == SSH1_MSG_CHANNEL_CLOSE ? "" :
4232 "_CONFIRMATION", c ? "half-open" : "nonexistent",
4233 i));
4234 }
4235}
4236
4237static void ssh1_msg_channel_data(Ssh ssh, struct Packet *pktin)
4238{
4239 /* Data sent down one of our channels. */
4240 int i = ssh_pkt_getuint32(pktin);
4241 char *p;
aa63ab7e 4242 unsigned int len;
51df0ab5 4243 struct ssh_channel *c;
4244
4245 ssh_pkt_getstring(pktin, &p, &len);
4246
4247 c = find234(ssh->channels, &i, ssh_channelfind);
4248 if (c) {
4249 int bufsize = 0;
4250 switch (c->type) {
4251 case CHAN_X11:
4252 bufsize = x11_send(c->u.x11.s, p, len);
4253 break;
4254 case CHAN_SOCKDATA:
4255 bufsize = pfd_send(c->u.pfd.s, p, len);
4256 break;
4257 case CHAN_AGENT:
4258 /* Data for an agent message. Buffer it. */
4259 while (len > 0) {
4260 if (c->u.a.lensofar < 4) {
aa63ab7e 4261 unsigned int l = min(4 - c->u.a.lensofar, len);
51df0ab5 4262 memcpy(c->u.a.msglen + c->u.a.lensofar, p,
4263 l);
4264 p += l;
4265 len -= l;
4266 c->u.a.lensofar += l;
4267 }
4268 if (c->u.a.lensofar == 4) {
4269 c->u.a.totallen =
4270 4 + GET_32BIT(c->u.a.msglen);
4271 c->u.a.message = snewn(c->u.a.totallen,
4272 unsigned char);
4273 memcpy(c->u.a.message, c->u.a.msglen, 4);
4274 }
4275 if (c->u.a.lensofar >= 4 && len > 0) {
aa63ab7e 4276 unsigned int l =
51df0ab5 4277 min(c->u.a.totallen - c->u.a.lensofar,
4278 len);
4279 memcpy(c->u.a.message + c->u.a.lensofar, p,
4280 l);
4281 p += l;
4282 len -= l;
4283 c->u.a.lensofar += l;
4284 }
4285 if (c->u.a.lensofar == c->u.a.totallen) {
4286 void *reply;
4287 int replylen;
4288 if (agent_query(c->u.a.message,
4289 c->u.a.totallen,
4290 &reply, &replylen,
4291 ssh_agentf_callback, c))
4292 ssh_agentf_callback(c, reply, replylen);
4293 sfree(c->u.a.message);
4294 c->u.a.lensofar = 0;
4295 }
4296 }
4297 bufsize = 0; /* agent channels never back up */
4298 break;
4299 }
4300 if (!c->v.v1.throttling && bufsize > SSH1_BUFFER_LIMIT) {
4301 c->v.v1.throttling = 1;
4302 ssh1_throttle(ssh, +1);
4303 }
4304 }
4305}
4306
4307static void ssh1_smsg_exit_status(Ssh ssh, struct Packet *pktin)
4308{
4309 char buf[100];
4310 ssh->exitcode = ssh_pkt_getuint32(pktin);
4311 sprintf(buf, "Server sent command exit status %d",
4312 ssh->exitcode);
4313 logevent(buf);
4314 send_packet(ssh, SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
4315 /*
4316 * In case `helpful' firewalls or proxies tack
4317 * extra human-readable text on the end of the
4318 * session which we might mistake for another
4319 * encrypted packet, we close the session once
4320 * we've sent EXIT_CONFIRMATION.
4321 */
4322 ssh_closing((Plug)ssh, NULL, 0, 0);
4323}
4324
b09eaa88 4325static void do_ssh1_connection(Ssh ssh, unsigned char *in, int inlen,
4326 struct Packet *pktin)
32874aea 4327{
b09eaa88 4328 crBegin(ssh->do_ssh1_connection_crstate);
fb09bf1c 4329
51df0ab5 4330 ssh->packet_dispatch[SSH1_SMSG_STDOUT_DATA] =
4331 ssh->packet_dispatch[SSH1_SMSG_STDERR_DATA] =
4332 ssh1_smsg_stdout_stderr_data;
4333
4334 ssh->packet_dispatch[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION] =
4335 ssh1_msg_channel_open_confirmation;
4336 ssh->packet_dispatch[SSH1_MSG_CHANNEL_OPEN_FAILURE] =
4337 ssh1_msg_channel_open_failure;
4338 ssh->packet_dispatch[SSH1_MSG_CHANNEL_CLOSE] =
4339 ssh->packet_dispatch[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION] =
4340 ssh1_msg_channel_close;
4341 ssh->packet_dispatch[SSH1_MSG_CHANNEL_DATA] = ssh1_msg_channel_data;
4342 ssh->packet_dispatch[SSH1_SMSG_EXIT_STATUS] = ssh1_smsg_exit_status;
4343
86916870 4344 if (ssh->cfg.agentfwd && agent_exists()) {
32874aea 4345 logevent("Requesting agent forwarding");
51470298 4346 send_packet(ssh, SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
32874aea 4347 do {
4348 crReturnV;
ff3187f6 4349 } while (!pktin);
4350 if (pktin->type != SSH1_SMSG_SUCCESS
4351 && pktin->type != SSH1_SMSG_FAILURE) {
6b5cf8b4 4352 bombout(("Protocol confusion"));
7ffdbc1a 4353 crStopV;
ff3187f6 4354 } else if (pktin->type == SSH1_SMSG_FAILURE) {
32874aea 4355 logevent("Agent forwarding refused");
4356 } else {
4357 logevent("Agent forwarding enabled");
51470298 4358 ssh->agentfwd_enabled = TRUE;
51df0ab5 4359 ssh->packet_dispatch[SSH1_SMSG_AGENT_OPEN] = ssh1_smsg_agent_open;
db7d555c 4360 }
dacbd0e8 4361 }
4362
86916870 4363 if (ssh->cfg.x11_forward) {
32874aea 4364 char proto[20], data[64];
4365 logevent("Requesting X11 forwarding");
302121de 4366 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
86916870 4367 data, sizeof(data), ssh->cfg.x11_auth);
4368 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
51470298 4369 if (ssh->v1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) {
4370 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
32874aea 4371 PKT_STR, proto, PKT_STR, data,
86916870 4372 PKT_INT, x11_get_screen_number(ssh->cfg.x11_display),
421d6835 4373 PKT_END);
32874aea 4374 } else {
51470298 4375 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
32874aea 4376 PKT_STR, proto, PKT_STR, data, PKT_END);
4377 }
4378 do {
4379 crReturnV;
ff3187f6 4380 } while (!pktin);
4381 if (pktin->type != SSH1_SMSG_SUCCESS
4382 && pktin->type != SSH1_SMSG_FAILURE) {
6b5cf8b4 4383 bombout(("Protocol confusion"));
7ffdbc1a 4384 crStopV;
ff3187f6 4385 } else if (pktin->type == SSH1_SMSG_FAILURE) {
32874aea 4386 logevent("X11 forwarding refused");
4387 } else {
4388 logevent("X11 forwarding enabled");
51470298 4389 ssh->X11_fwd_enabled = TRUE;
51df0ab5 4390 ssh->packet_dispatch[SSH1_SMSG_X11_OPEN] = ssh1_smsg_x11_open;
9c964e85 4391 }
4392 }
4393
06fadff5 4394 ssh_setup_portfwd(ssh, &ssh->cfg);
4395 ssh->packet_dispatch[SSH1_MSG_PORT_OPEN] = ssh1_msg_port_open;
d74d141c 4396
86916870 4397 if (!ssh->cfg.nopty) {
a5dd8467 4398 /* Unpick the terminal-speed string. */
4399 /* XXX perhaps we should allow no speeds to be sent. */
db219738 4400 ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
4401 sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
a5dd8467 4402 /* Send the pty request. */
51470298 4403 send_packet(ssh, SSH1_CMSG_REQUEST_PTY,
86916870 4404 PKT_STR, ssh->cfg.termtype,
51470298 4405 PKT_INT, ssh->term_height,
4406 PKT_INT, ssh->term_width,
a5dd8467 4407 PKT_INT, 0, PKT_INT, 0, /* width,height in pixels */
db219738 4408 PKT_CHAR, 192, PKT_INT, ssh->ispeed, /* TTY_OP_ISPEED */
4409 PKT_CHAR, 193, PKT_INT, ssh->ospeed, /* TTY_OP_OSPEED */
a5dd8467 4410 PKT_CHAR, 0, PKT_END);
51470298 4411 ssh->state = SSH_STATE_INTERMED;
32874aea 4412 do {
4413 crReturnV;
ff3187f6 4414 } while (!pktin);
4415 if (pktin->type != SSH1_SMSG_SUCCESS
4416 && pktin->type != SSH1_SMSG_FAILURE) {
6b5cf8b4 4417 bombout(("Protocol confusion"));
7ffdbc1a 4418 crStopV;
ff3187f6 4419 } else if (pktin->type == SSH1_SMSG_FAILURE) {
51470298 4420 c_write_str(ssh, "Server refused to allocate pty\r\n");
4421 ssh->editing = ssh->echoing = 1;
32874aea 4422 }
a5dd8467 4423 logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
db219738 4424 ssh->ospeed, ssh->ispeed);
0965bee0 4425 } else {
51470298 4426 ssh->editing = ssh->echoing = 1;
374330e2 4427 }
4428
86916870 4429 if (ssh->cfg.compression) {
51470298 4430 send_packet(ssh, SSH1_CMSG_REQUEST_COMPRESSION, PKT_INT, 6, PKT_END);
32874aea 4431 do {
4432 crReturnV;
ff3187f6 4433 } while (!pktin);
4434 if (pktin->type != SSH1_SMSG_SUCCESS
4435 && pktin->type != SSH1_SMSG_FAILURE) {
6b5cf8b4 4436 bombout(("Protocol confusion"));
7ffdbc1a 4437 crStopV;
ff3187f6 4438 } else if (pktin->type == SSH1_SMSG_FAILURE) {
51470298 4439 c_write_str(ssh, "Server refused to compress\r\n");
32874aea 4440 }
4ba9b64b 4441 logevent("Started compression");
51470298 4442 ssh->v1_compressing = TRUE;
5366aed8 4443 ssh->cs_comp_ctx = zlib_compress_init();
4444 logevent("Initialised zlib (RFC1950) compression");
4445 ssh->sc_comp_ctx = zlib_decompress_init();
4446 logevent("Initialised zlib (RFC1950) decompression");
4ba9b64b 4447 }
4448
fd5e5847 4449 /*
4450 * Start the shell or command.
4451 *
4452 * Special case: if the first-choice command is an SSH2
4453 * subsystem (hence not usable here) and the second choice
4454 * exists, we fall straight back to that.
4455 */
4456 {
86916870 4457 char *cmd = ssh->cfg.remote_cmd_ptr;
fd5e5847 4458
86916870 4459 if (ssh->cfg.ssh_subsys && ssh->cfg.remote_cmd_ptr2) {
4460 cmd = ssh->cfg.remote_cmd_ptr2;
51470298 4461 ssh->fallback_cmd = TRUE;
fd5e5847 4462 }
4463 if (*cmd)
51470298 4464 send_packet(ssh, SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END);
fd5e5847 4465 else
51470298 4466 send_packet(ssh, SSH1_CMSG_EXEC_SHELL, PKT_END);
fd5e5847 4467 logevent("Started session");
4468 }
374330e2 4469
51470298 4470 ssh->state = SSH_STATE_SESSION;
4471 if (ssh->size_needed)
4472 ssh_size(ssh, ssh->term_width, ssh->term_height);
4473 if (ssh->eof_needed)
4474 ssh_special(ssh, TS_EOF);
374330e2 4475
b9d7bcad 4476 if (ssh->ldisc)
4477 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
51470298 4478 ssh->send_ok = 1;
4479 ssh->channels = newtree234(ssh_channelcmp);
374330e2 4480 while (1) {
d74d141c 4481
51df0ab5 4482 /*
4483 * By this point, most incoming packets are already being
4484 * handled by the dispatch table, and we need only pay
4485 * attention to the unusual ones.
4486 */
0357890f 4487
51df0ab5 4488 crReturnV;
4489 if (pktin) {
4490 if (pktin->type == SSH1_SMSG_SUCCESS) {
972a41c8 4491 /* may be from EXEC_SHELL on some servers */
ff3187f6 4492 } else if (pktin->type == SSH1_SMSG_FAILURE) {
972a41c8 4493 /* may be from EXEC_SHELL on some servers
374330e2 4494 * if no pty is available or in other odd cases. Ignore */
374330e2 4495 } else {
ff3187f6 4496 bombout(("Strange packet received: type %d", pktin->type));
7ffdbc1a 4497 crStopV;
374330e2 4498 }
4499 } else {
8df7a775 4500 while (inlen > 0) {
4501 int len = min(inlen, 512);
9a10ecf4 4502 send_packet(ssh, SSH1_CMSG_STDIN_DATA, PKTT_DATA,
4503 PKT_INT, len, PKT_DATA, in, len,
4504 PKTT_OTHER, PKT_END);
8df7a775 4505 in += len;
4506 inlen -= len;
4507 }
374330e2 4508 }
4509 }
4510
4511 crFinishV;
4512}
4513
4514/*
b09eaa88 4515 * Handle the top-level SSH2 protocol.
4516 */
4517static void ssh1_msg_debug(Ssh ssh, struct Packet *pktin)
4518{
4519 char *buf, *msg;
4520 int msglen;
4521
4522 ssh_pkt_getstring(pktin, &msg, &msglen);
4523 buf = dupprintf("Remote debug message: %.*s", msglen, msg);
4524 logevent(buf);
4525 sfree(buf);
4526}
4527
4528static void ssh1_msg_disconnect(Ssh ssh, struct Packet *pktin)
4529{
4530 /* log reason code in disconnect message */
4531 char *msg;
4532 int msglen;
4533
4534 ssh_pkt_getstring(pktin, &msg, &msglen);
4535 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen, msg));
4536}
4537
4538void ssh_msg_ignore(Ssh ssh, struct Packet *pktin)
4539{
4540 /* Do nothing, because we're ignoring it! Duhh. */
4541}
4542
4543static void ssh1_protocol_setup(Ssh ssh)
4544{
4545 int i;
4546
4547 /*
4548 * Most messages are handled by the coroutines.
4549 */
4550 for (i = 0; i < 256; i++)
4551 ssh->packet_dispatch[i] = NULL;
4552
4553 /*
4554 * These special message types we install handlers for.
4555 */
4556 ssh->packet_dispatch[SSH1_MSG_DISCONNECT] = ssh1_msg_disconnect;
4557 ssh->packet_dispatch[SSH1_MSG_IGNORE] = ssh_msg_ignore;
4558 ssh->packet_dispatch[SSH1_MSG_DEBUG] = ssh1_msg_debug;
4559}
4560
4561static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen,
4562 struct Packet *pktin)
4563{
4564 if (ssh->state == SSH_STATE_CLOSED)
4565 return;
4566
4567 if (pktin && ssh->packet_dispatch[pktin->type]) {
4568 ssh->packet_dispatch[pktin->type](ssh, pktin);
4569 return;
4570 }
4571
4572 if (!ssh->protocol_initial_phase_done) {
4573 if (do_ssh1_login(ssh, in, inlen, pktin))
4574 ssh->protocol_initial_phase_done = TRUE;
4575 else
4576 return;
4577 }
4578
4579 do_ssh1_connection(ssh, in, inlen, pktin);
4580}
4581
4582/*
e5574168 4583 * Utility routine for decoding comma-separated strings in KEXINIT.
4584 */
32874aea 4585static int in_commasep_string(char *needle, char *haystack, int haylen)
4586{
57356d63 4587 int needlen;
4588 if (!needle || !haystack) /* protect against null pointers */
4589 return 0;
4590 needlen = strlen(needle);
e5574168 4591 while (1) {
32874aea 4592 /*
4593 * Is it at the start of the string?
4594 */
4595 if (haylen >= needlen && /* haystack is long enough */
4596 !memcmp(needle, haystack, needlen) && /* initial match */
4597 (haylen == needlen || haystack[needlen] == ',')
4598 /* either , or EOS follows */
4599 )
4600 return 1;
4601 /*
4602 * If not, search for the next comma and resume after that.
4603 * If no comma found, terminate.
4604 */
4605 while (haylen > 0 && *haystack != ',')
4606 haylen--, haystack++;
4607 if (haylen == 0)
4608 return 0;
4609 haylen--, haystack++; /* skip over comma itself */
e5574168 4610 }
4611}
4612
4613/*
d39f364a 4614 * SSH2 key creation method.
4615 */
d8baa528 4616static void ssh2_mkkey(Ssh ssh, Bignum K, unsigned char *H,
4617 unsigned char *sessid, char chr,
4618 unsigned char *keyspace)
32874aea 4619{
d39f364a 4620 SHA_State s;
4621 /* First 20 bytes. */
4622 SHA_Init(&s);
51470298 4623 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
088bde77 4624 sha_mpint(&s, K);
d39f364a 4625 SHA_Bytes(&s, H, 20);
4626 SHA_Bytes(&s, &chr, 1);
5e0d7cb8 4627 SHA_Bytes(&s, sessid, 20);
d39f364a 4628 SHA_Final(&s, keyspace);
4629 /* Next 20 bytes. */
4630 SHA_Init(&s);
51470298 4631 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
088bde77 4632 sha_mpint(&s, K);
d39f364a 4633 SHA_Bytes(&s, H, 20);
4634 SHA_Bytes(&s, keyspace, 20);
32874aea 4635 SHA_Final(&s, keyspace + 20);
d39f364a 4636}
4637
4638/*
7cca0d81 4639 * Handle the SSH2 transport layer.
e5574168 4640 */
ff3187f6 4641static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen,
4642 struct Packet *pktin)
e5574168 4643{
51470298 4644 struct do_ssh2_transport_state {
4645 int nbits, pbits, warn;
4646 Bignum p, g, e, f, K;
4647 int kex_init_value, kex_reply_value;
4648 const struct ssh_mac **maclist;
4649 int nmacs;
4650 const struct ssh2_cipher *cscipher_tobe;
4651 const struct ssh2_cipher *sccipher_tobe;
4652 const struct ssh_mac *csmac_tobe;
4653 const struct ssh_mac *scmac_tobe;
4654 const struct ssh_compress *cscomp_tobe;
4655 const struct ssh_compress *sccomp_tobe;
4656 char *hostkeydata, *sigdata, *keystr, *fingerprint;
4657 int hostkeylen, siglen;
4658 void *hkey; /* actual host key */
4659 unsigned char exchange_hash[20];
83e7d008 4660 int n_preferred_kex;
4661 const struct ssh_kex *preferred_kex[KEX_MAX];
51470298 4662 int n_preferred_ciphers;
4663 const struct ssh2_ciphers *preferred_ciphers[CIPHER_MAX];
4664 const struct ssh_compress *preferred_comp;
e13bba36 4665 int got_session_id, activated_authconn;
ff3187f6 4666 struct Packet *pktout;
51470298 4667 };
4668 crState(do_ssh2_transport_state);
4669
4670 crBegin(ssh->do_ssh2_transport_crstate);
4671
4672 s->cscipher_tobe = s->sccipher_tobe = NULL;
4673 s->csmac_tobe = s->scmac_tobe = NULL;
4674 s->cscomp_tobe = s->sccomp_tobe = NULL;
4675
e13bba36 4676 s->got_session_id = s->activated_authconn = FALSE;
e5574168 4677
e13bba36 4678 /*
4679 * Be prepared to work around the buggy MAC problem.
4680 */
4681 if (ssh->remote_bugs & BUG_SSH2_HMAC)
4682 s->maclist = buggymacs, s->nmacs = lenof(buggymacs);
4683 else
4684 s->maclist = macs, s->nmacs = lenof(macs);
4685
4686 begin_key_exchange:
149d2abc 4687 ssh->pkt_ctx &= ~SSH2_PKTCTX_KEX_MASK;
51470298 4688 {
e13bba36 4689 int i, j, commalist_started;
4690
51470298 4691 /*
83e7d008 4692 * Set up the preferred key exchange. (NULL => warn below here)
4693 */
4694 s->n_preferred_kex = 0;
4695 for (i = 0; i < KEX_MAX; i++) {
4696 switch (ssh->cfg.ssh_kexlist[i]) {
4697 case KEX_DHGEX:
4698 s->preferred_kex[s->n_preferred_kex++] =
4699 &ssh_diffiehellman_gex;
4700 break;
4701 case KEX_DHGROUP14:
4702 s->preferred_kex[s->n_preferred_kex++] =
4703 &ssh_diffiehellman_group14;
4704 break;
4705 case KEX_DHGROUP1:
4706 s->preferred_kex[s->n_preferred_kex++] =
4707 &ssh_diffiehellman_group1;
4708 break;
4709 case CIPHER_WARN:
4710 /* Flag for later. Don't bother if it's the last in
4711 * the list. */
4712 if (i < KEX_MAX - 1) {
4713 s->preferred_kex[s->n_preferred_kex++] = NULL;
4714 }
4715 break;
4716 }
4717 }
83e7d008 4718
83e7d008 4719 /*
51470298 4720 * Set up the preferred ciphers. (NULL => warn below here)
4721 */
4722 s->n_preferred_ciphers = 0;
4723 for (i = 0; i < CIPHER_MAX; i++) {
86916870 4724 switch (ssh->cfg.ssh_cipherlist[i]) {
51470298 4725 case CIPHER_BLOWFISH:
4726 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_blowfish;
4727 break;
4728 case CIPHER_DES:
86916870 4729 if (ssh->cfg.ssh2_des_cbc) {
51470298 4730 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_des;
4731 }
4732 break;
4733 case CIPHER_3DES:
4734 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_3des;
4735 break;
4736 case CIPHER_AES:
4737 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_aes;
4738 break;
4739 case CIPHER_WARN:
4740 /* Flag for later. Don't bother if it's the last in
4741 * the list. */
4742 if (i < CIPHER_MAX - 1) {
4743 s->preferred_ciphers[s->n_preferred_ciphers++] = NULL;
4744 }
4745 break;
ca20bfcf 4746 }
ca20bfcf 4747 }
7591b9ff 4748
e13bba36 4749 /*
4750 * Set up preferred compression.
4751 */
4752 if (ssh->cfg.compression)
4753 s->preferred_comp = &ssh_zlib;
4754 else
4755 s->preferred_comp = &ssh_comp_none;
51470298 4756
4757 /*
590f6a5f 4758 * Enable queueing of outgoing auth- or connection-layer
4759 * packets while we are in the middle of a key exchange.
4760 */
4761 ssh->queueing = TRUE;
4762
4763 /*
9442dd57 4764 * Flag that KEX is in progress.
4765 */
4766 ssh->kex_in_progress = TRUE;
4767
4768 /*
51470298 4769 * Construct and send our key exchange packet.
4770 */
ff3187f6 4771 s->pktout = ssh2_pkt_init(SSH2_MSG_KEXINIT);
51470298 4772 for (i = 0; i < 16; i++)
ff3187f6 4773 ssh2_pkt_addbyte(s->pktout, (unsigned char) random_byte());
51470298 4774 /* List key exchange algorithms. */
ff3187f6 4775 ssh2_pkt_addstring_start(s->pktout);
83e7d008 4776 commalist_started = 0;
4777 for (i = 0; i < s->n_preferred_kex; i++) {
4778 const struct ssh_kex *k = s->preferred_kex[i];
4779 if (!k) continue; /* warning flag */
4780 if (commalist_started)
ff3187f6 4781 ssh2_pkt_addstring_str(s->pktout, ",");
83e7d008 4782 ssh2_pkt_addstring_str(s->pktout, s->preferred_kex[i]->name);
4783 commalist_started = 1;
32874aea 4784 }
51470298 4785 /* List server host key algorithms. */
ff3187f6 4786 ssh2_pkt_addstring_start(s->pktout);
51470298 4787 for (i = 0; i < lenof(hostkey_algs); i++) {
ff3187f6 4788 ssh2_pkt_addstring_str(s->pktout, hostkey_algs[i]->name);
51470298 4789 if (i < lenof(hostkey_algs) - 1)
ff3187f6 4790 ssh2_pkt_addstring_str(s->pktout, ",");
32874aea 4791 }
51470298 4792 /* List client->server encryption algorithms. */
ff3187f6 4793 ssh2_pkt_addstring_start(s->pktout);
83e7d008 4794 commalist_started = 0;
51470298 4795 for (i = 0; i < s->n_preferred_ciphers; i++) {
4796 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4797 if (!c) continue; /* warning flag */
4798 for (j = 0; j < c->nciphers; j++) {
83e7d008 4799 if (commalist_started)
ff3187f6 4800 ssh2_pkt_addstring_str(s->pktout, ",");
4801 ssh2_pkt_addstring_str(s->pktout, c->list[j]->name);
83e7d008 4802 commalist_started = 1;
51470298 4803 }
4804 }
4805 /* List server->client encryption algorithms. */
ff3187f6 4806 ssh2_pkt_addstring_start(s->pktout);
83e7d008 4807 commalist_started = 0;
51470298 4808 for (i = 0; i < s->n_preferred_ciphers; i++) {
4809 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4810 if (!c) continue; /* warning flag */
4811 for (j = 0; j < c->nciphers; j++) {
83e7d008 4812 if (commalist_started)
ff3187f6 4813 ssh2_pkt_addstring_str(s->pktout, ",");
4814 ssh2_pkt_addstring_str(s->pktout, c->list[j]->name);
83e7d008 4815 commalist_started = 1;
51470298 4816 }
4817 }
4818 /* List client->server MAC algorithms. */
ff3187f6 4819 ssh2_pkt_addstring_start(s->pktout);
51470298 4820 for (i = 0; i < s->nmacs; i++) {
ff3187f6 4821 ssh2_pkt_addstring_str(s->pktout, s->maclist[i]->name);
51470298 4822 if (i < s->nmacs - 1)
ff3187f6 4823 ssh2_pkt_addstring_str(s->pktout, ",");
51470298 4824 }
4825 /* List server->client MAC algorithms. */
ff3187f6 4826 ssh2_pkt_addstring_start(s->pktout);
51470298 4827 for (i = 0; i < s->nmacs; i++) {
ff3187f6 4828 ssh2_pkt_addstring_str(s->pktout, s->maclist[i]->name);
51470298 4829 if (i < s->nmacs - 1)
ff3187f6 4830 ssh2_pkt_addstring_str(s->pktout, ",");
51470298 4831 }
4832 /* List client->server compression algorithms. */
ff3187f6 4833 ssh2_pkt_addstring_start(s->pktout);
f6e0abe2 4834 assert(lenof(compressions) > 1);
ff3187f6 4835 ssh2_pkt_addstring_str(s->pktout, s->preferred_comp->name);
f6e0abe2 4836 for (i = 0; i < lenof(compressions); i++) {
4837 const struct ssh_compress *c = compressions[i];
4838 if (c != s->preferred_comp) {
ff3187f6 4839 ssh2_pkt_addstring_str(s->pktout, ",");
4840 ssh2_pkt_addstring_str(s->pktout, c->name);
f6e0abe2 4841 }
51470298 4842 }
4843 /* List server->client compression algorithms. */
ff3187f6 4844 ssh2_pkt_addstring_start(s->pktout);
f6e0abe2 4845 assert(lenof(compressions) > 1);
ff3187f6 4846 ssh2_pkt_addstring_str(s->pktout, s->preferred_comp->name);
f6e0abe2 4847 for (i = 0; i < lenof(compressions); i++) {
4848 const struct ssh_compress *c = compressions[i];
4849 if (c != s->preferred_comp) {
ff3187f6 4850 ssh2_pkt_addstring_str(s->pktout, ",");
4851 ssh2_pkt_addstring_str(s->pktout, c->name);
f6e0abe2 4852 }
51470298 4853 }
4854 /* List client->server languages. Empty list. */
ff3187f6 4855 ssh2_pkt_addstring_start(s->pktout);
51470298 4856 /* List server->client languages. Empty list. */
ff3187f6 4857 ssh2_pkt_addstring_start(s->pktout);
51470298 4858 /* First KEX packet does _not_ follow, because we're not that brave. */
ff3187f6 4859 ssh2_pkt_addbool(s->pktout, FALSE);
51470298 4860 /* Reserved. */
ff3187f6 4861 ssh2_pkt_adduint32(s->pktout, 0);
e5574168 4862 }
0db56f73 4863
51470298 4864 ssh->exhash = ssh->exhashbase;
ff3187f6 4865 sha_string(&ssh->exhash, s->pktout->data + 5, s->pktout->length - 5);
0db56f73 4866
590f6a5f 4867 ssh2_pkt_send_noqueue(ssh, s->pktout);
e5574168 4868
ff3187f6 4869 if (!pktin)
4870 crWaitUntil(pktin);
4871 if (pktin->length > 5)
4872 sha_string(&ssh->exhash, pktin->data + 5, pktin->length - 5);
e5574168 4873
4874 /*
4875 * Now examine the other side's KEXINIT to see what we're up
4876 * to.
4877 */
51470298 4878 {
4879 char *str;
4880 int i, j, len;
4881
ff3187f6 4882 if (pktin->type != SSH2_MSG_KEXINIT) {
6b5cf8b4 4883 bombout(("expected key exchange packet from server"));
7ffdbc1a 4884 crStop(0);
32874aea 4885 }
51470298 4886 ssh->kex = NULL;
4887 ssh->hostkey = NULL;
4888 s->cscipher_tobe = NULL;
4889 s->sccipher_tobe = NULL;
4890 s->csmac_tobe = NULL;
4891 s->scmac_tobe = NULL;
4892 s->cscomp_tobe = NULL;
4893 s->sccomp_tobe = NULL;
ff3187f6 4894 pktin->savedpos += 16; /* skip garbage cookie */
4895 ssh_pkt_getstring(pktin, &str, &len); /* key exchange algorithms */
83e7d008 4896 s->warn = 0;
4897 for (i = 0; i < s->n_preferred_kex; i++) {
4898 const struct ssh_kex *k = s->preferred_kex[i];
4899 if (!k) {
4900 s->warn = 1;
4901 } else if (in_commasep_string(k->name, str, len)) {
4902 ssh->kex = k;
4903 }
4904 if (ssh->kex) {
bb348ab1 4905 if (s->warn) {
4906 sk_set_frozen(ssh->s, 1);
83e7d008 4907 askalg(ssh->frontend, "key-exchange algorithm",
4908 ssh->kex->name);
bb348ab1 4909 sk_set_frozen(ssh->s, 0);
4910 }
51470298 4911 break;
4912 }
32874aea 4913 }
83e7d008 4914 if (!ssh->kex) {
4915 bombout(("Couldn't agree a key exchange algorithm (available: %s)",
4916 str ? str : "(null)"));
4917 crStop(0);
4918 }
ff3187f6 4919 ssh_pkt_getstring(pktin, &str, &len); /* host key algorithms */
51470298 4920 for (i = 0; i < lenof(hostkey_algs); i++) {
4921 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
4922 ssh->hostkey = hostkey_algs[i];
4923 break;
4924 }
4925 }
ff3187f6 4926 ssh_pkt_getstring(pktin, &str, &len); /* client->server cipher */
51470298 4927 s->warn = 0;
4928 for (i = 0; i < s->n_preferred_ciphers; i++) {
4929 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4930 if (!c) {
4931 s->warn = 1;
4932 } else {
4933 for (j = 0; j < c->nciphers; j++) {
4934 if (in_commasep_string(c->list[j]->name, str, len)) {
4935 s->cscipher_tobe = c->list[j];
4936 break;
4937 }
ca20bfcf 4938 }
32874aea 4939 }
51470298 4940 if (s->cscipher_tobe) {
bb348ab1 4941 if (s->warn) {
4942 sk_set_frozen(ssh->s, 1);
83e7d008 4943 askalg(ssh->frontend, "client-to-server cipher",
4944 s->cscipher_tobe->name);
bb348ab1 4945 sk_set_frozen(ssh->s, 0);
4946 }
51470298 4947 break;
4948 }
32874aea 4949 }
51470298 4950 if (!s->cscipher_tobe) {
6b5cf8b4 4951 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
57356d63 4952 str ? str : "(null)"));
7ffdbc1a 4953 crStop(0);
ca20bfcf 4954 }
0ef8f407 4955
ff3187f6 4956 ssh_pkt_getstring(pktin, &str, &len); /* server->client cipher */
51470298 4957 s->warn = 0;
4958 for (i = 0; i < s->n_preferred_ciphers; i++) {
4959 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4960 if (!c) {
4961 s->warn = 1;
4962 } else {
4963 for (j = 0; j < c->nciphers; j++) {
4964 if (in_commasep_string(c->list[j]->name, str, len)) {
4965 s->sccipher_tobe = c->list[j];
4966 break;
4967 }
ca20bfcf 4968 }
32874aea 4969 }
51470298 4970 if (s->sccipher_tobe) {
bb348ab1 4971 if (s->warn) {
4972 sk_set_frozen(ssh->s, 1);
83e7d008 4973 askalg(ssh->frontend, "server-to-client cipher",
4974 s->sccipher_tobe->name);
bb348ab1 4975 sk_set_frozen(ssh->s, 0);
4976 }
51470298 4977 break;
4978 }
32874aea 4979 }
51470298 4980 if (!s->sccipher_tobe) {
6b5cf8b4 4981 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
57356d63 4982 str ? str : "(null)"));
7ffdbc1a 4983 crStop(0);
ca20bfcf 4984 }
0ef8f407 4985
ff3187f6 4986 ssh_pkt_getstring(pktin, &str, &len); /* client->server mac */
51470298 4987 for (i = 0; i < s->nmacs; i++) {
4988 if (in_commasep_string(s->maclist[i]->name, str, len)) {
4989 s->csmac_tobe = s->maclist[i];
4990 break;
4991 }
32874aea 4992 }
ff3187f6 4993 ssh_pkt_getstring(pktin, &str, &len); /* server->client mac */
51470298 4994 for (i = 0; i < s->nmacs; i++) {
4995 if (in_commasep_string(s->maclist[i]->name, str, len)) {
4996 s->scmac_tobe = s->maclist[i];
4997 break;
4998 }
32874aea 4999 }
ff3187f6 5000 ssh_pkt_getstring(pktin, &str, &len); /* client->server compression */
51470298 5001 for (i = 0; i < lenof(compressions) + 1; i++) {
5002 const struct ssh_compress *c =
5003 i == 0 ? s->preferred_comp : compressions[i - 1];
5004 if (in_commasep_string(c->name, str, len)) {
5005 s->cscomp_tobe = c;
5006 break;
5007 }
32874aea 5008 }
ff3187f6 5009 ssh_pkt_getstring(pktin, &str, &len); /* server->client compression */
51470298 5010 for (i = 0; i < lenof(compressions) + 1; i++) {
5011 const struct ssh_compress *c =
5012 i == 0 ? s->preferred_comp : compressions[i - 1];
5013 if (in_commasep_string(c->name, str, len)) {
5014 s->sccomp_tobe = c;
5015 break;
5016 }
32874aea 5017 }
e5574168 5018 }
e5574168 5019
5020 /*
7bd5a860 5021 * Work out the number of bits of key we will need from the key
5022 * exchange. We start with the maximum key length of either
5023 * cipher...
5024 */
5025 {
32874aea 5026 int csbits, scbits;
7bd5a860 5027
51470298 5028 csbits = s->cscipher_tobe->keylen;
5029 scbits = s->sccipher_tobe->keylen;
5030 s->nbits = (csbits > scbits ? csbits : scbits);
7bd5a860 5031 }
5032 /* The keys only have 160-bit entropy, since they're based on
5033 * a SHA-1 hash. So cap the key size at 160 bits. */
51470298 5034 if (s->nbits > 160)
5035 s->nbits = 160;
7bd5a860 5036
5037 /*
a92dd380 5038 * If we're doing Diffie-Hellman group exchange, start by
5039 * requesting a group.
e5574168 5040 */
d1aaf71d 5041 if (!ssh->kex->pdata) {
32874aea 5042 logevent("Doing Diffie-Hellman group exchange");
51470298 5043 ssh->pkt_ctx |= SSH2_PKTCTX_DHGEX;
32874aea 5044 /*
5045 * Work out how big a DH group we will need to allow that
5046 * much data.
7bd5a860 5047 */
51470298 5048 s->pbits = 512 << ((s->nbits - 1) / 64);
ff3187f6 5049 s->pktout = ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST);
5050 ssh2_pkt_adduint32(s->pktout, s->pbits);
590f6a5f 5051 ssh2_pkt_send_noqueue(ssh, s->pktout);
32874aea 5052
ff3187f6 5053 crWaitUntil(pktin);
5054 if (pktin->type != SSH2_MSG_KEX_DH_GEX_GROUP) {
6b5cf8b4 5055 bombout(("expected key exchange group packet from server"));
7ffdbc1a 5056 crStop(0);
32874aea 5057 }
ff3187f6 5058 s->p = ssh2_pkt_getmp(pktin);
5059 s->g = ssh2_pkt_getmp(pktin);
5060 if (!s->p || !s->g) {
5061 bombout(("unable to read mp-ints from incoming group packet"));
5062 crStop(0);
5063 }
d1aaf71d 5064 ssh->kex_ctx = dh_setup_gex(s->p, s->g);
51470298 5065 s->kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
5066 s->kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY;
a92dd380 5067 } else {
d1aaf71d 5068 ssh->pkt_ctx |= SSH2_PKTCTX_DHGROUP;
5069 ssh->kex_ctx = dh_setup_group(ssh->kex);
51470298 5070 s->kex_init_value = SSH2_MSG_KEXDH_INIT;
5071 s->kex_reply_value = SSH2_MSG_KEXDH_REPLY;
d1aaf71d 5072 logeventf(ssh, "Using Diffie-Hellman with standard group \"%s\"",
5073 ssh->kex->groupname);
8d5de777 5074 }
e5574168 5075
a92dd380 5076 logevent("Doing Diffie-Hellman key exchange");
e5574168 5077 /*
a92dd380 5078 * Now generate and send e for Diffie-Hellman.
e5574168 5079 */
27cd7fc2 5080 s->e = dh_create_e(ssh->kex_ctx, s->nbits * 2);
ff3187f6 5081 s->pktout = ssh2_pkt_init(s->kex_init_value);
5082 ssh2_pkt_addmp(s->pktout, s->e);
590f6a5f 5083 ssh2_pkt_send_noqueue(ssh, s->pktout);
e5574168 5084
ff3187f6 5085 crWaitUntil(pktin);
5086 if (pktin->type != s->kex_reply_value) {
6b5cf8b4 5087 bombout(("expected key exchange reply packet from server"));
7ffdbc1a 5088 crStop(0);
7cca0d81 5089 }
ff3187f6 5090 ssh_pkt_getstring(pktin, &s->hostkeydata, &s->hostkeylen);
5091 s->f = ssh2_pkt_getmp(pktin);
5092 if (!s->f) {
5093 bombout(("unable to parse key exchange reply packet"));
5094 crStop(0);
5095 }
5096 ssh_pkt_getstring(pktin, &s->sigdata, &s->siglen);
e5574168 5097
27cd7fc2 5098 s->K = dh_find_K(ssh->kex_ctx, s->f);
e5574168 5099
51470298 5100 sha_string(&ssh->exhash, s->hostkeydata, s->hostkeylen);
5101 if (ssh->kex == &ssh_diffiehellman_gex) {
5102 sha_uint32(&ssh->exhash, s->pbits);
5103 sha_mpint(&ssh->exhash, s->p);
5104 sha_mpint(&ssh->exhash, s->g);
a92dd380 5105 }
51470298 5106 sha_mpint(&ssh->exhash, s->e);
5107 sha_mpint(&ssh->exhash, s->f);
5108 sha_mpint(&ssh->exhash, s->K);
5109 SHA_Final(&ssh->exhash, s->exchange_hash);
e5574168 5110
27cd7fc2 5111 dh_cleanup(ssh->kex_ctx);
fabd1805 5112 ssh->kex_ctx = NULL;
3709bfe9 5113
7cca0d81 5114#if 0
765c4200 5115 debug(("Exchange hash is:\n"));
51470298 5116 dmemdump(s->exchange_hash, 20);
7cca0d81 5117#endif
5118
51470298 5119 s->hkey = ssh->hostkey->newkey(s->hostkeydata, s->hostkeylen);
5120 if (!s->hkey ||
5121 !ssh->hostkey->verifysig(s->hkey, s->sigdata, s->siglen,
d8baa528 5122 (char *)s->exchange_hash, 20)) {
6b5cf8b4 5123 bombout(("Server's host key did not match the signature supplied"));
7ffdbc1a 5124 crStop(0);
8d5de777 5125 }
e5574168 5126
5127 /*
7cca0d81 5128 * Authenticate remote host: verify host key. (We've already
5129 * checked the signature of the exchange hash.)
e5574168 5130 */
51470298 5131 s->keystr = ssh->hostkey->fmtkey(s->hkey);
5132 s->fingerprint = ssh->hostkey->fingerprint(s->hkey);
bb348ab1 5133 sk_set_frozen(ssh->s, 1);
a8327734 5134 verify_ssh_host_key(ssh->frontend,
5135 ssh->savedhost, ssh->savedport, ssh->hostkey->keytype,
51470298 5136 s->keystr, s->fingerprint);
bb348ab1 5137 sk_set_frozen(ssh->s, 0);
e13bba36 5138 if (!s->got_session_id) { /* don't bother logging this in rekeys */
5e0d7cb8 5139 logevent("Host key fingerprint is:");
51470298 5140 logevent(s->fingerprint);
5e0d7cb8 5141 }
51470298 5142 sfree(s->fingerprint);
5143 sfree(s->keystr);
5144 ssh->hostkey->freekey(s->hkey);
d39f364a 5145
5146 /*
9442dd57 5147 * The exchange hash from the very first key exchange is also
5148 * the session id, used in session key construction and
5149 * authentication.
5150 */
e13bba36 5151 if (!s->got_session_id) {
9442dd57 5152 memcpy(ssh->v2_session_id, s->exchange_hash,
5153 sizeof(s->exchange_hash));
e13bba36 5154 s->got_session_id = TRUE;
5155 }
9442dd57 5156
5157 /*
7cca0d81 5158 * Send SSH2_MSG_NEWKEYS.
d39f364a 5159 */
ff3187f6 5160 s->pktout = ssh2_pkt_init(SSH2_MSG_NEWKEYS);
590f6a5f 5161 ssh2_pkt_send_noqueue(ssh, s->pktout);
9442dd57 5162 ssh->outgoing_data_size = 0; /* start counting from here */
5163
5164 /*
5165 * We've sent client NEWKEYS, so create and initialise
c64fe7d4 5166 * client-to-server session keys.
9442dd57 5167 */
5168 if (ssh->cs_cipher_ctx)
5169 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
5170 ssh->cscipher = s->cscipher_tobe;
5171 ssh->cs_cipher_ctx = ssh->cscipher->make_context();
5172
5173 if (ssh->cs_mac_ctx)
5174 ssh->csmac->free_context(ssh->cs_mac_ctx);
5175 ssh->csmac = s->csmac_tobe;
5176 ssh->cs_mac_ctx = ssh->csmac->make_context();
5177
5178 if (ssh->cs_comp_ctx)
5179 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
5180 ssh->cscomp = s->cscomp_tobe;
5181 ssh->cs_comp_ctx = ssh->cscomp->compress_init();
5182
5183 /*
5184 * Set IVs on client-to-server keys. Here we use the exchange
5185 * hash from the _first_ key exchange.
5186 */
5187 {
5188 unsigned char keyspace[40];
5189 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'C',keyspace);
5190 ssh->cscipher->setkey(ssh->cs_cipher_ctx, keyspace);
5191 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'A',keyspace);
5192 ssh->cscipher->setiv(ssh->cs_cipher_ctx, keyspace);
5193 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'E',keyspace);
5194 ssh->csmac->setkey(ssh->cs_mac_ctx, keyspace);
5195 }
5196
5197 logeventf(ssh, "Initialised %.200s client->server encryption",
5198 ssh->cscipher->text_name);
5199 logeventf(ssh, "Initialised %.200s client->server MAC algorithm",
5200 ssh->csmac->text_name);
5201 if (ssh->cscomp->text_name)
5202 logeventf(ssh, "Initialised %s compression",
5203 ssh->cscomp->text_name);
590f6a5f 5204
5205 /*
5206 * Now our end of the key exchange is complete, we can send all
5207 * our queued higher-layer packets.
5208 */
5209 ssh->queueing = FALSE;
5210 ssh2_pkt_queuesend(ssh);
d39f364a 5211
5212 /*
8406eaf9 5213 * Expect SSH2_MSG_NEWKEYS from server.
5214 */
ff3187f6 5215 crWaitUntil(pktin);
5216 if (pktin->type != SSH2_MSG_NEWKEYS) {
6b5cf8b4 5217 bombout(("expected new-keys packet from server"));
7ffdbc1a 5218 crStop(0);
8406eaf9 5219 }
9442dd57 5220 ssh->incoming_data_size = 0; /* start counting from here */
8406eaf9 5221
5222 /*
9442dd57 5223 * We've seen server NEWKEYS, so create and initialise
5224 * server-to-client session keys.
d39f364a 5225 */
371e569c 5226 if (ssh->sc_cipher_ctx)
5227 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
51470298 5228 ssh->sccipher = s->sccipher_tobe;
371e569c 5229 ssh->sc_cipher_ctx = ssh->sccipher->make_context();
e0e1a00d 5230
e0e1a00d 5231 if (ssh->sc_mac_ctx)
5232 ssh->scmac->free_context(ssh->sc_mac_ctx);
51470298 5233 ssh->scmac = s->scmac_tobe;
e0e1a00d 5234 ssh->sc_mac_ctx = ssh->scmac->make_context();
5235
5366aed8 5236 if (ssh->sc_comp_ctx)
5237 ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
51470298 5238 ssh->sccomp = s->sccomp_tobe;
5366aed8 5239 ssh->sc_comp_ctx = ssh->sccomp->decompress_init();
5240
d39f364a 5241 /*
9442dd57 5242 * Set IVs on server-to-client keys. Here we use the exchange
5243 * hash from the _first_ key exchange.
d39f364a 5244 */
51470298 5245 {
5246 unsigned char keyspace[40];
51470298 5247 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'D',keyspace);
371e569c 5248 ssh->sccipher->setkey(ssh->sc_cipher_ctx, keyspace);
51470298 5249 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'B',keyspace);
371e569c 5250 ssh->sccipher->setiv(ssh->sc_cipher_ctx, keyspace);
51470298 5251 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'F',keyspace);
e0e1a00d 5252 ssh->scmac->setkey(ssh->sc_mac_ctx, keyspace);
51470298 5253 }
57356d63 5254 logeventf(ssh, "Initialised %.200s server->client encryption",
5255 ssh->sccipher->text_name);
6c135243 5256 logeventf(ssh, "Initialised %.200s server->client MAC algorithm",
5257 ssh->scmac->text_name);
57356d63 5258 if (ssh->sccomp->text_name)
5259 logeventf(ssh, "Initialised %s decompression",
5260 ssh->sccomp->text_name);
9442dd57 5261
5262 /*
5263 * Free key exchange data.
5264 */
679539d7 5265 freebn(s->f);
679539d7 5266 freebn(s->K);
b3949e7e 5267 if (ssh->kex == &ssh_diffiehellman_gex) {
5268 freebn(s->g);
5269 freebn(s->p);
5270 }
d39f364a 5271
033b4cef 5272 /*
e13bba36 5273 * Key exchange is over. Loop straight back round if we have a
5274 * deferred rekey reason.
5275 */
5276 if (ssh->deferred_rekey_reason) {
5277 logevent(ssh->deferred_rekey_reason);
5278 pktin = NULL;
5279 ssh->deferred_rekey_reason = NULL;
5280 goto begin_key_exchange;
5281 }
5282
5283 /*
5284 * Otherwise, schedule a timer for our next rekey.
9442dd57 5285 */
5286 ssh->kex_in_progress = FALSE;
e6c1536e 5287 ssh->last_rekey = GETTICKCOUNT();
d57f70af 5288 if (ssh->cfg.ssh_rekey_time != 0)
5289 ssh->next_rekey = schedule_timer(ssh->cfg.ssh_rekey_time*60*TICKSPERSEC,
5290 ssh2_timer, ssh);
e13bba36 5291
9442dd57 5292 /*
0db56f73 5293 * If this is the first key exchange phase, we must pass the
5294 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
5295 * wants to see it but because it will need time to initialise
5296 * itself before it sees an actual packet. In subsequent key
5297 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
5298 * it would only confuse the layer above.
5299 */
e13bba36 5300 if (s->activated_authconn) {
b09eaa88 5301 crReturn(1);
0db56f73 5302 }
e13bba36 5303 s->activated_authconn = TRUE;
0db56f73 5304
5305 /*
7cca0d81 5306 * Now we're encrypting. Begin returning 1 to the protocol main
5307 * function so that other things can run on top of the
5308 * transport. If we ever see a KEXINIT, we must go back to the
5309 * start.
9442dd57 5310 *
5311 * We _also_ go back to the start if we see pktin==NULL and
5312 * inlen==-1, because this is a special signal meaning
5313 * `initiate client-driven rekey', and `in' contains a message
5314 * giving the reason for the rekey.
033b4cef 5315 */
9442dd57 5316 while (!((pktin && pktin->type == SSH2_MSG_KEXINIT) ||
5317 (!pktin && inlen == -1))) {
f382c87d 5318 wait_for_rekey:
32874aea 5319 crReturn(1);
e96adf72 5320 }
9442dd57 5321 if (pktin) {
5322 logevent("Server initiated key re-exchange");
5323 } else {
f382c87d 5324 /*
5325 * Special case: if the server bug is set that doesn't
5326 * allow rekeying, we give a different log message and
5327 * continue waiting. (If such a server _initiates_ a rekey,
5328 * we process it anyway!)
5329 */
5330 if ((ssh->remote_bugs & BUG_SSH2_REKEY)) {
5331 logeventf(ssh, "Server bug prevents key re-exchange (%s)",
5332 (char *)in);
5333 /* Reset the counters, so that at least this message doesn't
5334 * hit the event log _too_ often. */
5335 ssh->outgoing_data_size = 0;
5336 ssh->incoming_data_size = 0;
5337 if (ssh->cfg.ssh_rekey_time != 0) {
5338 ssh->next_rekey =
5339 schedule_timer(ssh->cfg.ssh_rekey_time*60*TICKSPERSEC,
5340 ssh2_timer, ssh);
5341 }
5342 goto wait_for_rekey; /* this is utterly horrid */
5343 } else {
5344 logeventf(ssh, "Initiating key re-exchange (%s)", (char *)in);
5345 logevent((char *)in);
5346 }
9442dd57 5347 }
7cca0d81 5348 goto begin_key_exchange;
e5574168 5349
5350 crFinish(1);
5351}
5352
7cca0d81 5353/*
783415f8 5354 * Add data to an SSH2 channel output buffer.
5355 */
32874aea 5356static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
5357 int len)
5358{
5471d09a 5359 bufchain_add(&c->v.v2.outbuffer, buf, len);
783415f8 5360}
5361
5362/*
5363 * Attempt to send data on an SSH2 channel.
5364 */
5471d09a 5365static int ssh2_try_send(struct ssh_channel *c)
32874aea 5366{
51470298 5367 Ssh ssh = c->ssh;
ff3187f6 5368 struct Packet *pktout;
51470298 5369
5471d09a 5370 while (c->v.v2.remwindow > 0 && bufchain_size(&c->v.v2.outbuffer) > 0) {
5371 int len;
5372 void *data;
5373 bufchain_prefix(&c->v.v2.outbuffer, &data, &len);
5374 if ((unsigned)len > c->v.v2.remwindow)
5375 len = c->v.v2.remwindow;
5376 if ((unsigned)len > c->v.v2.remmaxpkt)
5377 len = c->v.v2.remmaxpkt;
ff3187f6 5378 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
5379 ssh2_pkt_adduint32(pktout, c->remoteid);
5380 dont_log_data(ssh, pktout, PKTLOG_OMIT);
5381 ssh2_pkt_addstring_start(pktout);
5382 ssh2_pkt_addstring_data(pktout, data, len);
5383 end_log_omission(ssh, pktout);
5384 ssh2_pkt_send(ssh, pktout);
5471d09a 5385 bufchain_consume(&c->v.v2.outbuffer, len);
5386 c->v.v2.remwindow -= len;
5387 }
5388
5389 /*
5390 * After having sent as much data as we can, return the amount
5391 * still buffered.
5392 */
5393 return bufchain_size(&c->v.v2.outbuffer);
5394}
5395
5396/*
5397 * Potentially enlarge the window on an SSH2 channel.
5398 */
5399static void ssh2_set_window(struct ssh_channel *c, unsigned newwin)
5400{
51470298 5401 Ssh ssh = c->ssh;
5402
6b69f42e 5403 /*
5404 * Never send WINDOW_ADJUST for a channel that the remote side
5405 * already thinks it's closed; there's no point, since it won't
5406 * be sending any more data anyway.
5407 */
5408 if (c->closes != 0)
5409 return;
5410
5471d09a 5411 if (newwin > c->v.v2.locwindow) {
ff3187f6 5412 struct Packet *pktout;
5413
5414 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
5415 ssh2_pkt_adduint32(pktout, c->remoteid);
5416 ssh2_pkt_adduint32(pktout, newwin - c->v.v2.locwindow);
5417 ssh2_pkt_send(ssh, pktout);
5471d09a 5418 c->v.v2.locwindow = newwin;
783415f8 5419 }
5420}
5421
51df0ab5 5422static void ssh2_msg_channel_window_adjust(Ssh ssh, struct Packet *pktin)
b09eaa88 5423{
5424 unsigned i = ssh_pkt_getuint32(pktin);
5425 struct ssh_channel *c;
5426 c = find234(ssh->channels, &i, ssh_channelfind);
5427 if (c && !c->closes)
5428 c->v.v2.remwindow += ssh_pkt_getuint32(pktin);
5429}
5430
51df0ab5 5431static void ssh2_msg_channel_data(Ssh ssh, struct Packet *pktin)
5432{
5433 char *data;
aa63ab7e 5434 unsigned int length;
51df0ab5 5435 unsigned i = ssh_pkt_getuint32(pktin);
5436 struct ssh_channel *c;
5437 c = find234(ssh->channels, &i, ssh_channelfind);
5438 if (!c)
5439 return; /* nonexistent channel */
5440 if (pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
5441 ssh_pkt_getuint32(pktin) != SSH2_EXTENDED_DATA_STDERR)
5442 return; /* extended but not stderr */
5443 ssh_pkt_getstring(pktin, &data, &length);
5444 if (data) {
5445 int bufsize = 0;
5446 c->v.v2.locwindow -= length;
5447 switch (c->type) {
5448 case CHAN_MAINSESSION:
5449 bufsize =
5450 from_backend(ssh->frontend, pktin->type ==
5451 SSH2_MSG_CHANNEL_EXTENDED_DATA,
5452 data, length);
5453 break;
5454 case CHAN_X11:
5455 bufsize = x11_send(c->u.x11.s, data, length);
5456 break;
5457 case CHAN_SOCKDATA:
5458 bufsize = pfd_send(c->u.pfd.s, data, length);
5459 break;
5460 case CHAN_AGENT:
5461 while (length > 0) {
5462 if (c->u.a.lensofar < 4) {
aa63ab7e 5463 unsigned int l = min(4 - c->u.a.lensofar, length);
51df0ab5 5464 memcpy(c->u.a.msglen + c->u.a.lensofar,
5465 data, l);
5466 data += l;
5467 length -= l;
5468 c->u.a.lensofar += l;
5469 }
5470 if (c->u.a.lensofar == 4) {
5471 c->u.a.totallen =
5472 4 + GET_32BIT(c->u.a.msglen);
5473 c->u.a.message = snewn(c->u.a.totallen,
5474 unsigned char);
5475 memcpy(c->u.a.message, c->u.a.msglen, 4);
5476 }
5477 if (c->u.a.lensofar >= 4 && length > 0) {
aa63ab7e 5478 unsigned int l =
51df0ab5 5479 min(c->u.a.totallen - c->u.a.lensofar,
5480 length);
5481 memcpy(c->u.a.message + c->u.a.lensofar,
5482 data, l);
5483 data += l;
5484 length -= l;
5485 c->u.a.lensofar += l;
5486 }
5487 if (c->u.a.lensofar == c->u.a.totallen) {
5488 void *reply;
5489 int replylen;
5490 if (agent_query(c->u.a.message,
5491 c->u.a.totallen,
5492 &reply, &replylen,
5493 ssh_agentf_callback, c))
5494 ssh_agentf_callback(c, reply, replylen);
5495 sfree(c->u.a.message);
5496 c->u.a.lensofar = 0;
5497 }
5498 }
5499 bufsize = 0;
5500 break;
5501 }
5502 /*
5503 * If we are not buffering too much data,
5504 * enlarge the window again at the remote side.
5505 */
5506 if (bufsize < OUR_V2_WINSIZE)
5507 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
5508 }
5509}
5510
5511static void ssh2_msg_channel_eof(Ssh ssh, struct Packet *pktin)
5512{
5513 unsigned i = ssh_pkt_getuint32(pktin);
5514 struct ssh_channel *c;
5515
5516 c = find234(ssh->channels, &i, ssh_channelfind);
5517 if (!c)
5518 return; /* nonexistent channel */
5519
5520 if (c->type == CHAN_X11) {
5521 /*
5522 * Remote EOF on an X11 channel means we should
5523 * wrap up and close the channel ourselves.
5524 */
5525 x11_close(c->u.x11.s);
5526 sshfwd_close(c);
5527 } else if (c->type == CHAN_AGENT) {
5528 sshfwd_close(c);
5529 } else if (c->type == CHAN_SOCKDATA) {
5530 pfd_close(c->u.pfd.s);
5531 sshfwd_close(c);
5532 }
5533}
5534
5535static void ssh2_msg_channel_close(Ssh ssh, struct Packet *pktin)
5536{
5537 unsigned i = ssh_pkt_getuint32(pktin);
5538 struct ssh_channel *c;
5539 struct Packet *pktout;
5540
5541 c = find234(ssh->channels, &i, ssh_channelfind);
5542 if (!c || ((int)c->remoteid) == -1) {
5543 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5544 c ? "half-open" : "nonexistent", i));
5545 return;
5546 }
5547 /* Do pre-close processing on the channel. */
5548 switch (c->type) {
5549 case CHAN_MAINSESSION:
5550 ssh->mainchan = NULL;
5551 update_specials_menu(ssh->frontend);
5552 break;
5553 case CHAN_X11:
5554 if (c->u.x11.s != NULL)
5555 x11_close(c->u.x11.s);
5556 sshfwd_close(c);
5557 break;
5558 case CHAN_AGENT:
5559 sshfwd_close(c);
5560 break;
5561 case CHAN_SOCKDATA:
5562 if (c->u.pfd.s != NULL)
5563 pfd_close(c->u.pfd.s);
5564 sshfwd_close(c);
5565 break;
5566 }
5567 if (c->closes == 0) {
5568 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
5569 ssh2_pkt_adduint32(pktout, c->remoteid);
5570 ssh2_pkt_send(ssh, pktout);
5571 }
5572 del234(ssh->channels, c);
5573 bufchain_clear(&c->v.v2.outbuffer);
5574 sfree(c);
5575
5576 /*
5577 * See if that was the last channel left open.
5578 * (This is only our termination condition if we're
5579 * not running in -N mode.)
5580 */
5581 if (!ssh->cfg.ssh_no_shell && count234(ssh->channels) == 0) {
5582 logevent("All channels closed. Disconnecting");
5583#if 0
5584 /*
5585 * We used to send SSH_MSG_DISCONNECT here,
5586 * because I'd believed that _every_ conforming
5587 * SSH2 connection had to end with a disconnect
5588 * being sent by at least one side; apparently
5589 * I was wrong and it's perfectly OK to
5590 * unceremoniously slam the connection shut
5591 * when you're done, and indeed OpenSSH feels
5592 * this is more polite than sending a
5593 * DISCONNECT. So now we don't.
5594 */
5595 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
5596 ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
5597 ssh2_pkt_addstring(s->pktout, "All open channels closed");
5598 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
5599 ssh2_pkt_send_noqueue(ssh, s->pktout);
5600#endif
5601 ssh_closing((Plug)ssh, NULL, 0, 0);
5602 }
5603}
5604
5605static void ssh2_msg_channel_open_confirmation(Ssh ssh, struct Packet *pktin)
5606{
5607 unsigned i = ssh_pkt_getuint32(pktin);
5608 struct ssh_channel *c;
5609 struct Packet *pktout;
5610
5611 c = find234(ssh->channels, &i, ssh_channelfind);
5612 if (!c)
5613 return; /* nonexistent channel */
5614 if (c->type != CHAN_SOCKDATA_DORMANT)
5615 return; /* dunno why they're confirming this */
5616 c->remoteid = ssh_pkt_getuint32(pktin);
5617 c->type = CHAN_SOCKDATA;
5618 c->v.v2.remwindow = ssh_pkt_getuint32(pktin);
5619 c->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin);
5620 if (c->u.pfd.s)
5621 pfd_confirm(c->u.pfd.s);
5622 if (c->closes) {
5623 /*
5624 * We have a pending close on this channel,
5625 * which we decided on before the server acked
5626 * the channel open. So now we know the
5627 * remoteid, we can close it again.
5628 */
5629 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
5630 ssh2_pkt_adduint32(pktout, c->remoteid);
5631 ssh2_pkt_send(ssh, pktout);
5632 }
5633}
5634
5635static void ssh2_msg_channel_open_failure(Ssh ssh, struct Packet *pktin)
5636{
5637 static const char *const reasons[] = {
5638 "<unknown reason code>",
5639 "Administratively prohibited",
5640 "Connect failed",
5641 "Unknown channel type",
5642 "Resource shortage",
5643 };
5644 unsigned i = ssh_pkt_getuint32(pktin);
5645 unsigned reason_code;
5646 char *reason_string;
5647 int reason_length;
5648 char *message;
5649 struct ssh_channel *c;
5650 c = find234(ssh->channels, &i, ssh_channelfind);
5651 if (!c)
5652 return; /* nonexistent channel */
5653 if (c->type != CHAN_SOCKDATA_DORMANT)
5654 return; /* dunno why they're failing this */
5655
5656 reason_code = ssh_pkt_getuint32(pktin);
5657 if (reason_code >= lenof(reasons))
5658 reason_code = 0; /* ensure reasons[reason_code] in range */
5659 ssh_pkt_getstring(pktin, &reason_string, &reason_length);
5660 message = dupprintf("Forwarded connection refused by"
5661 " server: %s [%.*s]", reasons[reason_code],
5662 reason_length, reason_string);
5663 logevent(message);
5664 sfree(message);
5665
5666 pfd_close(c->u.pfd.s);
5667
5668 del234(ssh->channels, c);
5669 sfree(c);
5670}
5671
5672static void ssh2_msg_channel_request(Ssh ssh, struct Packet *pktin)
5673{
5674 unsigned localid;
5675 char *type;
5676 int typelen, want_reply;
5677 int reply = SSH2_MSG_CHANNEL_FAILURE; /* default */
5678 struct ssh_channel *c;
5679 struct Packet *pktout;
5680
5681 localid = ssh_pkt_getuint32(pktin);
5682 ssh_pkt_getstring(pktin, &type, &typelen);
5683 want_reply = ssh2_pkt_getbool(pktin);
5684
5685 /*
5686 * First, check that the channel exists. Otherwise,
5687 * we can instantly disconnect with a rude message.
5688 */
5689 c = find234(ssh->channels, &localid, ssh_channelfind);
5690 if (!c) {
5691 char buf[80];
5692 sprintf(buf, "Received channel request for nonexistent"
5693 " channel %d", localid);
5694 logevent(buf);
5695 pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
5696 ssh2_pkt_adduint32(pktout, SSH2_DISCONNECT_BY_APPLICATION);
5697 ssh2_pkt_addstring(pktout, buf);
5698 ssh2_pkt_addstring(pktout, "en"); /* language tag */
5699 ssh2_pkt_send_noqueue(ssh, pktout);
5700 connection_fatal(ssh->frontend, "%s", buf);
5701 ssh_closing((Plug)ssh, NULL, 0, 0);
5702 return;
5703 }
5704
5705 /*
5706 * Having got the channel number, we now look at
5707 * the request type string to see if it's something
5708 * we recognise.
5709 */
5710 if (c == ssh->mainchan) {
5711 /*
5712 * We recognise "exit-status" and "exit-signal" on
5713 * the primary channel.
5714 */
5715 if (typelen == 11 &&
5716 !memcmp(type, "exit-status", 11)) {
5717
5718 ssh->exitcode = ssh_pkt_getuint32(pktin);
5719 logeventf(ssh, "Server sent command exit status %d",
5720 ssh->exitcode);
5721 reply = SSH2_MSG_CHANNEL_SUCCESS;
5722
5723 } else if (typelen == 11 &&
5724 !memcmp(type, "exit-signal", 11)) {
5725
5726 int is_plausible = TRUE, is_int = FALSE;
5727 char *fmt_sig = "", *fmt_msg = "";
5728 char *msg;
5729 int msglen = 0, core = FALSE;
5730 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
5731 * provide an `int' for the signal, despite its
5732 * having been a `string' in the drafts since at
5733 * least 2001. (Fixed in session.c 1.147.) Try to
5734 * infer which we can safely parse it as. */
5735 {
5736 unsigned char *p = pktin->body +
5737 pktin->savedpos;
5738 long len = pktin->length - pktin->savedpos;
5739 unsigned long num = GET_32BIT(p); /* what is it? */
5740 /* If it's 0, it hardly matters; assume string */
5741 if (num == 0) {
5742 is_int = FALSE;
5743 } else {
5744 int maybe_int = FALSE, maybe_str = FALSE;
5745#define CHECK_HYPOTHESIS(offset, result) \
5746 do { \
5747 long q = offset; \
5748 if (q >= 0 && q+4 <= len) { \
5749 q = q + 4 + GET_32BIT(p+q); \
5750 if (q >= 0 && q+4 <= len && \
5751 (q = q + 4 + GET_32BIT(p+q)) && q == len) \
5752 result = TRUE; \
5753 } \
5754 } while(0)
5755 CHECK_HYPOTHESIS(4+1, maybe_int);
5756 CHECK_HYPOTHESIS(4+num+1, maybe_str);
5757#undef CHECK_HYPOTHESIS
5758 if (maybe_int && !maybe_str)
5759 is_int = TRUE;
5760 else if (!maybe_int && maybe_str)
5761 is_int = FALSE;
5762 else
5763 /* Crikey. Either or neither. Panic. */
5764 is_plausible = FALSE;
5765 }
5766 }
5767 if (is_plausible) {
5768 if (is_int) {
5769 /* Old non-standard OpenSSH. */
5770 int signum = ssh_pkt_getuint32(pktin);
5771 fmt_sig = dupprintf(" %d", signum);
5772 } else {
5773 /* As per the drafts. */
5774 char *sig;
5775 int siglen;
5776 ssh_pkt_getstring(pktin, &sig, &siglen);
5777 /* Signal name isn't supposed to be blank, but
5778 * let's cope gracefully if it is. */
5779 if (siglen) {
5780 fmt_sig = dupprintf(" \"%.*s\"",
5781 siglen, sig);
5782 }
5783 }
5784 core = ssh2_pkt_getbool(pktin);
5785 ssh_pkt_getstring(pktin, &msg, &msglen);
5786 if (msglen) {
5787 fmt_msg = dupprintf(" (\"%.*s\")", msglen, msg);
5788 }
5789 /* ignore lang tag */
5790 } /* else don't attempt to parse */
5791 logeventf(ssh, "Server exited on signal%s%s%s",
5792 fmt_sig, core ? " (core dumped)" : "",
5793 fmt_msg);
5794 if (*fmt_sig) sfree(fmt_sig);
5795 if (*fmt_msg) sfree(fmt_msg);
5796 reply = SSH2_MSG_CHANNEL_SUCCESS;
5797
5798 }
5799 } else {
5800 /*
5801 * This is a channel request we don't know
5802 * about, so we now either ignore the request
5803 * or respond with CHANNEL_FAILURE, depending
5804 * on want_reply.
5805 */
5806 reply = SSH2_MSG_CHANNEL_FAILURE;
5807 }
5808 if (want_reply) {
5809 pktout = ssh2_pkt_init(reply);
5810 ssh2_pkt_adduint32(pktout, c->remoteid);
5811 ssh2_pkt_send(ssh, pktout);
5812 }
5813}
5814
5815static void ssh2_msg_global_request(Ssh ssh, struct Packet *pktin)
5816{
5817 char *type;
5818 int typelen, want_reply;
5819 struct Packet *pktout;
5820
5821 ssh_pkt_getstring(pktin, &type, &typelen);
5822 want_reply = ssh2_pkt_getbool(pktin);
5823
5824 /*
5825 * We currently don't support any global requests
5826 * at all, so we either ignore the request or
5827 * respond with REQUEST_FAILURE, depending on
5828 * want_reply.
5829 */
5830 if (want_reply) {
5831 pktout = ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE);
5832 ssh2_pkt_send(ssh, pktout);
5833 }
5834}
5835
5836static void ssh2_msg_channel_open(Ssh ssh, struct Packet *pktin)
5837{
5838 char *type;
5839 int typelen;
5840 char *peeraddr;
5841 int peeraddrlen;
5842 int peerport;
5843 char *error = NULL;
5844 struct ssh_channel *c;
5845 unsigned remid, winsize, pktsize;
5846 struct Packet *pktout;
5847
5848 ssh_pkt_getstring(pktin, &type, &typelen);
5849 c = snew(struct ssh_channel);
5850 c->ssh = ssh;
5851
5852 remid = ssh_pkt_getuint32(pktin);
5853 winsize = ssh_pkt_getuint32(pktin);
5854 pktsize = ssh_pkt_getuint32(pktin);
5855
5856 if (typelen == 3 && !memcmp(type, "x11", 3)) {
5857 char *addrstr;
5858
5859 ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
5860 addrstr = snewn(peeraddrlen+1, char);
5861 memcpy(addrstr, peeraddr, peeraddrlen);
5862 addrstr[peeraddrlen] = '\0';
5863 peerport = ssh_pkt_getuint32(pktin);
5864
5865 logeventf(ssh, "Received X11 connect request from %s:%d",
5866 addrstr, peerport);
5867
5868 if (!ssh->X11_fwd_enabled)
5869 error = "X11 forwarding is not enabled";
5870 else if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
5871 ssh->x11auth, addrstr, peerport,
5872 &ssh->cfg) != NULL) {
5873 error = "Unable to open an X11 connection";
5874 } else {
5875 logevent("Opening X11 forward connection succeeded");
5876 c->type = CHAN_X11;
5877 }
5878
5879 sfree(addrstr);
5880 } else if (typelen == 15 &&
5881 !memcmp(type, "forwarded-tcpip", 15)) {
5882 struct ssh_rportfwd pf, *realpf;
5883 char *dummy;
5884 int dummylen;
5885 ssh_pkt_getstring(pktin, &dummy, &dummylen);/* skip address */
5886 pf.sport = ssh_pkt_getuint32(pktin);
5887 ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
5888 peerport = ssh_pkt_getuint32(pktin);
5889 realpf = find234(ssh->rportfwds, &pf, NULL);
5890 logeventf(ssh, "Received remote port %d open request "
5891 "from %s:%d", pf.sport, peeraddr, peerport);
5892 if (realpf == NULL) {
5893 error = "Remote port is not recognised";
5894 } else {
5895 const char *e = pfd_newconnect(&c->u.pfd.s,
5896 realpf->dhost,
5897 realpf->dport, c,
05581745 5898 &ssh->cfg,
5899 realpf->pfrec->addressfamily);
51df0ab5 5900 logeventf(ssh, "Attempting to forward remote port to "
5901 "%s:%d", realpf->dhost, realpf->dport);
5902 if (e != NULL) {
5903 logeventf(ssh, "Port open failed: %s", e);
5904 error = "Port open failed";
5905 } else {
5906 logevent("Forwarded port opened successfully");
5907 c->type = CHAN_SOCKDATA;
5908 }
5909 }
5910 } else if (typelen == 22 &&
5911 !memcmp(type, "auth-agent@openssh.com", 3)) {
5912 if (!ssh->agentfwd_enabled)
5913 error = "Agent forwarding is not enabled";
5914 else {
5915 c->type = CHAN_AGENT; /* identify channel type */
5916 c->u.a.lensofar = 0;
5917 }
5918 } else {
5919 error = "Unsupported channel type requested";
5920 }
5921
5922 c->remoteid = remid;
5923 if (error) {
5924 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE);
5925 ssh2_pkt_adduint32(pktout, c->remoteid);
5926 ssh2_pkt_adduint32(pktout, SSH2_OPEN_CONNECT_FAILED);
5927 ssh2_pkt_addstring(pktout, error);
5928 ssh2_pkt_addstring(pktout, "en"); /* language tag */
5929 ssh2_pkt_send(ssh, pktout);
5930 logeventf(ssh, "Rejected channel open: %s", error);
5931 sfree(c);
5932 } else {
5933 c->localid = alloc_channel_id(ssh);
5934 c->closes = 0;
5935 c->v.v2.locwindow = OUR_V2_WINSIZE;
5936 c->v.v2.remwindow = winsize;
5937 c->v.v2.remmaxpkt = pktsize;
5938 bufchain_init(&c->v.v2.outbuffer);
5939 add234(ssh->channels, c);
5940 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
5941 ssh2_pkt_adduint32(pktout, c->remoteid);
5942 ssh2_pkt_adduint32(pktout, c->localid);
5943 ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);
5944 ssh2_pkt_adduint32(pktout, 0x4000UL); /* our max pkt size */
5945 ssh2_pkt_send(ssh, pktout);
5946 }
5947}
5948
783415f8 5949/*
7cca0d81 5950 * Handle the SSH2 userauth and connection layers.
5951 */
ff3187f6 5952static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
5953 struct Packet *pktin)
7cca0d81 5954{
51470298 5955 struct do_ssh2_authconn_state {
5956 enum {
5957 AUTH_INVALID, AUTH_PUBLICKEY_AGENT, AUTH_PUBLICKEY_FILE,
5958 AUTH_PASSWORD,
5959 AUTH_KEYBOARD_INTERACTIVE
5960 } method;
5961 enum {
5962 AUTH_TYPE_NONE,
5963 AUTH_TYPE_PUBLICKEY,
5964 AUTH_TYPE_PUBLICKEY_OFFER_LOUD,
5965 AUTH_TYPE_PUBLICKEY_OFFER_QUIET,
5966 AUTH_TYPE_PASSWORD,
5967 AUTH_TYPE_KEYBOARD_INTERACTIVE,
5968 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
5969 } type;
5970 int gotit, need_pw, can_pubkey, can_passwd, can_keyb_inter;
6ac3a551 5971 int tried_pubkey_config, tried_agent;
5972 int kbd_inter_running, kbd_inter_refused;
51470298 5973 int we_are_in;
5974 int num_prompts, curr_prompt, echo;
5975 char username[100];
5976 int got_username;
85fdbe25 5977 char pwprompt[512];
51470298 5978 char password[100];
5979 void *publickey_blob;
5980 int publickey_bloblen;
5981 unsigned char request[5], *response, *p;
5982 int responselen;
5983 int keyi, nkeys;
5984 int authed;
5985 char *pkblob, *alg, *commentp;
5986 int pklen, alglen, commentlen;
5987 int siglen, retlen, len;
5988 char *q, *agentreq, *ret;
5989 int try_send;
73feed4f 5990 int num_env, env_left, env_ok;
ff3187f6 5991 struct Packet *pktout;
51470298 5992 };
5993 crState(do_ssh2_authconn_state);
5994
5995 crBegin(ssh->do_ssh2_authconn_crstate);
e5574168 5996
7cca0d81 5997 /*
5998 * Request userauth protocol, and await a response to it.
5999 */
ff3187f6 6000 s->pktout = ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
6001 ssh2_pkt_addstring(s->pktout, "ssh-userauth");
6002 ssh2_pkt_send(ssh, s->pktout);
6003 crWaitUntilV(pktin);
6004 if (pktin->type != SSH2_MSG_SERVICE_ACCEPT) {
6b5cf8b4 6005 bombout(("Server refused user authentication protocol"));
7ffdbc1a 6006 crStopV;
8d5de777 6007 }
7cca0d81 6008
6009 /*
1408a877 6010 * We repeat this whole loop, including the username prompt,
6011 * until we manage a successful authentication. If the user
51470298 6012 * types the wrong _password_, they can be sent back to the
6013 * beginning to try another username, if this is configured on.
6014 * (If they specify a username in the config, they are never
6015 * asked, even if they do give a wrong password.)
1408a877 6016 *
6017 * I think this best serves the needs of
6018 *
6019 * - the people who have no configuration, no keys, and just
6020 * want to try repeated (username,password) pairs until they
6021 * type both correctly
6022 *
6023 * - people who have keys and configuration but occasionally
6024 * need to fall back to passwords
6025 *
6026 * - people with a key held in Pageant, who might not have
6027 * logged in to a particular machine before; so they want to
6028 * type a username, and then _either_ their key will be
6029 * accepted, _or_ they will type a password. If they mistype
6030 * the username they will want to be able to get back and
6031 * retype it!
7cca0d81 6032 */
51470298 6033 s->username[0] = '\0';
6034 s->got_username = FALSE;
1408a877 6035 do {
1408a877 6036 /*
6037 * Get a username.
6038 */
86916870 6039 if (s->got_username && !ssh->cfg.change_username) {
5bb641e1 6040 /*
6041 * We got a username last time round this loop, and
6042 * with change_username turned off we don't try to get
6043 * it again.
6044 */
aa09f7d0 6045 } else if (!*ssh->cfg.username) {
c0a81592 6046 if (ssh_get_line && !ssh_getline_pw_only) {
32874aea 6047 if (!ssh_get_line("login as: ",
51470298 6048 s->username, sizeof(s->username), FALSE)) {
32874aea 6049 /*
6050 * get_line failed to get a username.
6051 * Terminate.
6052 */
6053 logevent("No username provided. Abandoning session.");
3bb2f322 6054 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 6055 crStopV;
32874aea 6056 }
6057 } else {
51470298 6058 int ret; /* need not be saved across crReturn */
6059 c_write_str(ssh, "login as: ");
6060 ssh->send_ok = 1;
6061 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
0405e71f 6062 do {
ff3187f6 6063 crWaitUntilV(!pktin);
51470298 6064 ret = process_userpass_input(ssh, in, inlen);
0405e71f 6065 } while (ret == 0);
6066 if (ret < 0)
6067 cleanup_exit(0);
4ca0c9d1 6068 c_write_str(ssh, "\r\n");
32874aea 6069 }
51470298 6070 s->username[strcspn(s->username, "\n\r")] = '\0';
7cca0d81 6071 } else {
57356d63 6072 char *stuff;
86916870 6073 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
51470298 6074 s->username[sizeof(s->username)-1] = '\0';
65a22376 6075 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
57356d63 6076 stuff = dupprintf("Using username \"%s\".\r\n", s->username);
51470298 6077 c_write_str(ssh, stuff);
57356d63 6078 sfree(stuff);
7cca0d81 6079 }
6080 }
51470298 6081 s->got_username = TRUE;
7cca0d81 6082
65a22376 6083 /*
1408a877 6084 * Send an authentication request using method "none": (a)
6085 * just in case it succeeds, and (b) so that we know what
6086 * authentication methods we can usefully try next.
65a22376 6087 */
51470298 6088 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6089
ff3187f6 6090 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6091 ssh2_pkt_addstring(s->pktout, s->username);
6092 ssh2_pkt_addstring(s->pktout, "ssh-connection");/* service requested */
6093 ssh2_pkt_addstring(s->pktout, "none"); /* method */
6094 ssh2_pkt_send(ssh, s->pktout);
51470298 6095 s->type = AUTH_TYPE_NONE;
6096 s->gotit = FALSE;
6097 s->we_are_in = FALSE;
6098
6099 s->tried_pubkey_config = FALSE;
6100 s->tried_agent = FALSE;
51470298 6101 s->kbd_inter_running = FALSE;
6ac3a551 6102 s->kbd_inter_refused = FALSE;
86916870 6103 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
9a30e26b 6104 if (!filename_is_null(ssh->cfg.keyfile)) {
231ee168 6105 int keytype;
6c6d9ed9 6106 logeventf(ssh, "Reading private key file \"%.150s\"",
6107 filename_to_str(&ssh->cfg.keyfile));
9a30e26b 6108 keytype = key_type(&ssh->cfg.keyfile);
51470298 6109 if (keytype == SSH_KEYTYPE_SSH2) {
6110 s->publickey_blob =
9a30e26b 6111 ssh2_userkey_loadpub(&ssh->cfg.keyfile, NULL,
222d54dc 6112 &s->publickey_bloblen, NULL);
51470298 6113 } else {
57356d63 6114 char *msgbuf;
c2ad7d0d 6115 logeventf(ssh, "Unable to use this key file (%s)",
a8327734 6116 key_type_to_str(keytype));
57356d63 6117 msgbuf = dupprintf("Unable to use key file \"%.150s\""
6c6d9ed9 6118 " (%s)\r\n",
6119 filename_to_str(&ssh->cfg.keyfile),
57356d63 6120 key_type_to_str(keytype));
51470298 6121 c_write_str(ssh, msgbuf);
57356d63 6122 sfree(msgbuf);
51470298 6123 s->publickey_blob = NULL;
231ee168 6124 }
396778f1 6125 } else
51470298 6126 s->publickey_blob = NULL;
65a22376 6127
1408a877 6128 while (1) {
6129 /*
6130 * Wait for the result of the last authentication request.
6131 */
51470298 6132 if (!s->gotit)
ff3187f6 6133 crWaitUntilV(pktin);
6134 while (pktin->type == SSH2_MSG_USERAUTH_BANNER) {
32874aea 6135 char *banner;
6136 int size;
6137 /*
6138 * Don't show the banner if we're operating in
6139 * non-verbose non-interactive mode. (It's probably
6140 * a script, which means nobody will read the
6141 * banner _anyway_, and moreover the printing of
6142 * the banner will screw up processing on the
6143 * output of (say) plink.)
6144 */
6145 if (flags & (FLAG_VERBOSE | FLAG_INTERACTIVE)) {
ff3187f6 6146 ssh_pkt_getstring(pktin, &banner, &size);
32874aea 6147 if (banner)
51470298 6148 c_write_untrusted(ssh, banner, size);
32874aea 6149 }
ff3187f6 6150 crWaitUntilV(pktin);
1408a877 6151 }
ff3187f6 6152 if (pktin->type == SSH2_MSG_USERAUTH_SUCCESS) {
1408a877 6153 logevent("Access granted");
51470298 6154 s->we_are_in = TRUE;
1408a877 6155 break;
6156 }
65a22376 6157
51470298 6158 if (s->kbd_inter_running &&
ff3187f6 6159 pktin->type == SSH2_MSG_USERAUTH_INFO_REQUEST) {
b3186d64 6160 /*
45068b27 6161 * This is either a further set-of-prompts packet
6162 * in keyboard-interactive authentication, or it's
6163 * the same one and we came back here with `gotit'
6164 * set. In the former case, we must reset the
6165 * curr_prompt variable.
b3186d64 6166 */
51470298 6167 if (!s->gotit)
6168 s->curr_prompt = 0;
4c6e53e3 6169 } else if (pktin->type == SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ) {
6170 /* FIXME: perhaps we should support this? */
6171 bombout(("PASSWD_CHANGEREQ not yet supported"));
6172 crStopV;
ff3187f6 6173 } else if (pktin->type != SSH2_MSG_USERAUTH_FAILURE) {
6b5cf8b4 6174 bombout(("Strange packet received during authentication: type %d",
ff3187f6 6175 pktin->type));
7ffdbc1a 6176 crStopV;
65a22376 6177 }
6178
51470298 6179 s->gotit = FALSE;
65a22376 6180
1408a877 6181 /*
6182 * OK, we're now sitting on a USERAUTH_FAILURE message, so
6183 * we can look at the string in it and know what we can
6184 * helpfully try next.
6185 */
ff3187f6 6186 if (pktin->type == SSH2_MSG_USERAUTH_FAILURE) {
1408a877 6187 char *methods;
6188 int methlen;
ff3187f6 6189 ssh_pkt_getstring(pktin, &methods, &methlen);
51470298 6190 s->kbd_inter_running = FALSE;
ff3187f6 6191 if (!ssh2_pkt_getbool(pktin)) {
1408a877 6192 /*
6193 * We have received an unequivocal Access
6194 * Denied. This can translate to a variety of
6195 * messages:
6196 *
6197 * - if we'd just tried "none" authentication,
6198 * it's not worth printing anything at all
6199 *
6200 * - if we'd just tried a public key _offer_,
6201 * the message should be "Server refused our
6202 * key" (or no message at all if the key
6203 * came from Pageant)
6204 *
6205 * - if we'd just tried anything else, the
6206 * message really should be "Access denied".
6207 *
6208 * Additionally, if we'd just tried password
6209 * authentication, we should break out of this
6210 * whole loop so as to go back to the username
91f57d1f 6211 * prompt (iff we're configured to allow
6212 * username change attempts).
1408a877 6213 */
51470298 6214 if (s->type == AUTH_TYPE_NONE) {
1408a877 6215 /* do nothing */
51470298 6216 } else if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD ||
6217 s->type == AUTH_TYPE_PUBLICKEY_OFFER_QUIET) {
6218 if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD)
6219 c_write_str(ssh, "Server refused our key\r\n");
1408a877 6220 logevent("Server refused public key");
51470298 6221 } else if (s->type==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET) {
4bdf7c46 6222 /* server declined keyboard-interactive; ignore */
1408a877 6223 } else {
51470298 6224 c_write_str(ssh, "Access denied\r\n");
1408a877 6225 logevent("Access denied");
91f57d1f 6226 if (s->type == AUTH_TYPE_PASSWORD &&
6227 ssh->cfg.change_username) {
6c9dce7c 6228 /* XXX perhaps we should allow
6229 * keyboard-interactive to do this too? */
51470298 6230 s->we_are_in = FALSE;
1408a877 6231 break;
6232 }
6233 }
6234 } else {
51470298 6235 c_write_str(ssh, "Further authentication required\r\n");
1408a877 6236 logevent("Further authentication required");
6237 }
65a22376 6238
51470298 6239 s->can_pubkey =
32874aea 6240 in_commasep_string("publickey", methods, methlen);
51470298 6241 s->can_passwd =
32874aea 6242 in_commasep_string("password", methods, methlen);
86916870 6243 s->can_keyb_inter = ssh->cfg.try_ki_auth &&
761187b6 6244 in_commasep_string("keyboard-interactive", methods, methlen);
1408a877 6245 }
65a22376 6246
51470298 6247 s->method = 0;
6248 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
954a9540 6249 s->need_pw = FALSE;
65a22376 6250
0405e71f 6251 /*
6252 * Most password/passphrase prompts will be
6253 * non-echoing, so we set this to 0 by default.
6254 * Exception is that some keyboard-interactive prompts
6255 * can be echoing, in which case we'll set this to 1.
6256 */
51470298 6257 s->echo = 0;
0405e71f 6258
51470298 6259 if (!s->method && s->can_pubkey &&
6260 agent_exists() && !s->tried_agent) {
1983e559 6261 /*
6262 * Attempt public-key authentication using Pageant.
6263 */
1983e559 6264 void *r;
51470298 6265 s->authed = FALSE;
1983e559 6266
51470298 6267 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6268 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
00db133f 6269
51470298 6270 s->tried_agent = TRUE;
1983e559 6271
6272 logevent("Pageant is running. Requesting keys.");
6273
6274 /* Request the keys held by the agent. */
51470298 6275 PUT_32BIT(s->request, 1);
6276 s->request[4] = SSH2_AGENTC_REQUEST_IDENTITIES;
839f10db 6277 if (!agent_query(s->request, 5, &r, &s->responselen,
6278 ssh_agent_callback, ssh)) {
6279 do {
6280 crReturnV;
ff3187f6 6281 if (pktin) {
839f10db 6282 bombout(("Unexpected data from server while"
6283 " waiting for agent response"));
6284 crStopV;
6285 }
ff3187f6 6286 } while (pktin || inlen > 0);
839f10db 6287 r = ssh->agent_response;
6288 s->responselen = ssh->agent_response_len;
6289 }
51470298 6290 s->response = (unsigned char *) r;
6291 if (s->response && s->responselen >= 5 &&
6292 s->response[4] == SSH2_AGENT_IDENTITIES_ANSWER) {
6293 s->p = s->response + 5;
6294 s->nkeys = GET_32BIT(s->p);
6295 s->p += 4;
32874aea 6296 {
6297 char buf[64];
51470298 6298 sprintf(buf, "Pageant has %d SSH2 keys", s->nkeys);
32874aea 6299 logevent(buf);
6300 }
51470298 6301 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
2d466ffd 6302 void *vret;
1983e559 6303
32874aea 6304 {
6305 char buf[64];
51470298 6306 sprintf(buf, "Trying Pageant key #%d", s->keyi);
32874aea 6307 logevent(buf);
6308 }
51470298 6309 s->pklen = GET_32BIT(s->p);
6310 s->p += 4;
6311 if (s->publickey_blob &&
6312 s->pklen == s->publickey_bloblen &&
6313 !memcmp(s->p, s->publickey_blob,
6314 s->publickey_bloblen)) {
396778f1 6315 logevent("This key matches configured key file");
51470298 6316 s->tried_pubkey_config = 1;
396778f1 6317 }
d8baa528 6318 s->pkblob = (char *)s->p;
51470298 6319 s->p += s->pklen;
6320 s->alglen = GET_32BIT(s->pkblob);
6321 s->alg = s->pkblob + 4;
6322 s->commentlen = GET_32BIT(s->p);
6323 s->p += 4;
d8baa528 6324 s->commentp = (char *)s->p;
51470298 6325 s->p += s->commentlen;
ff3187f6 6326 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6327 ssh2_pkt_addstring(s->pktout, s->username);
6328 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6329 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6330 ssh2_pkt_addbool(s->pktout, FALSE); /* no signature included */
6331 ssh2_pkt_addstring_start(s->pktout);
6332 ssh2_pkt_addstring_data(s->pktout, s->alg, s->alglen);
6333 ssh2_pkt_addstring_start(s->pktout);
6334 ssh2_pkt_addstring_data(s->pktout, s->pkblob, s->pklen);
6335 ssh2_pkt_send(ssh, s->pktout);
6336
6337 crWaitUntilV(pktin);
6338 if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
1983e559 6339 logevent("Key refused");
6340 continue;
6341 }
6342
32874aea 6343 if (flags & FLAG_VERBOSE) {
51470298 6344 c_write_str(ssh, "Authenticating with "
6345 "public key \"");
6346 c_write(ssh, s->commentp, s->commentlen);
6347 c_write_str(ssh, "\" from agent\r\n");
32874aea 6348 }
1983e559 6349
6350 /*
6351 * Server is willing to accept the key.
6352 * Construct a SIGN_REQUEST.
6353 */
ff3187f6 6354 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6355 ssh2_pkt_addstring(s->pktout, s->username);
6356 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6357 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6358 ssh2_pkt_addbool(s->pktout, TRUE);
6359 ssh2_pkt_addstring_start(s->pktout);
6360 ssh2_pkt_addstring_data(s->pktout, s->alg, s->alglen);
6361 ssh2_pkt_addstring_start(s->pktout);
6362 ssh2_pkt_addstring_data(s->pktout, s->pkblob, s->pklen);
6363
6364 s->siglen = s->pktout->length - 5 + 4 + 20;
dda87a28 6365 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
6366 s->siglen -= 4;
51470298 6367 s->len = 1; /* message type */
6368 s->len += 4 + s->pklen; /* key blob */
6369 s->len += 4 + s->siglen; /* data to sign */
6370 s->len += 4; /* flags */
3d88e64d 6371 s->agentreq = snewn(4 + s->len, char);
51470298 6372 PUT_32BIT(s->agentreq, s->len);
6373 s->q = s->agentreq + 4;
6374 *s->q++ = SSH2_AGENTC_SIGN_REQUEST;
6375 PUT_32BIT(s->q, s->pklen);
6376 s->q += 4;
6377 memcpy(s->q, s->pkblob, s->pklen);
6378 s->q += s->pklen;
6379 PUT_32BIT(s->q, s->siglen);
6380 s->q += 4;
1983e559 6381 /* Now the data to be signed... */
dda87a28 6382 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
6383 PUT_32BIT(s->q, 20);
6384 s->q += 4;
6385 }
51470298 6386 memcpy(s->q, ssh->v2_session_id, 20);
6387 s->q += 20;
ff3187f6 6388 memcpy(s->q, s->pktout->data + 5,
6389 s->pktout->length - 5);
6390 s->q += s->pktout->length - 5;
1983e559 6391 /* And finally the (zero) flags word. */
51470298 6392 PUT_32BIT(s->q, 0);
839f10db 6393 if (!agent_query(s->agentreq, s->len + 4,
6394 &vret, &s->retlen,
6395 ssh_agent_callback, ssh)) {
6396 do {
6397 crReturnV;
ff3187f6 6398 if (pktin) {
839f10db 6399 bombout(("Unexpected data from server"
6400 " while waiting for agent"
6401 " response"));
6402 crStopV;
6403 }
ff3187f6 6404 } while (pktin || inlen > 0);
839f10db 6405 vret = ssh->agent_response;
6406 s->retlen = ssh->agent_response_len;
6407 }
51470298 6408 s->ret = vret;
6409 sfree(s->agentreq);
6410 if (s->ret) {
6411 if (s->ret[4] == SSH2_AGENT_SIGN_RESPONSE) {
1983e559 6412 logevent("Sending Pageant's response");
ff3187f6 6413 ssh2_add_sigblob(ssh, s->pktout,
6414 s->pkblob, s->pklen,
51470298 6415 s->ret + 9,
6416 GET_32BIT(s->ret + 5));
ff3187f6 6417 ssh2_pkt_send(ssh, s->pktout);
51470298 6418 s->authed = TRUE;
1983e559 6419 break;
6420 } else {
32874aea 6421 logevent
6422 ("Pageant failed to answer challenge");
51470298 6423 sfree(s->ret);
1983e559 6424 }
6425 }
6426 }
51470298 6427 if (s->authed)
1983e559 6428 continue;
6429 }
29b1d0b3 6430 sfree(s->response);
1983e559 6431 }
6432
51470298 6433 if (!s->method && s->can_pubkey && s->publickey_blob
6434 && !s->tried_pubkey_config) {
1408a877 6435 unsigned char *pub_blob;
6436 char *algorithm, *comment;
6437 int pub_blob_len;
65a22376 6438
51470298 6439 s->tried_pubkey_config = TRUE;
65a22376 6440
51470298 6441 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6442 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
00db133f 6443
65a22376 6444 /*
1408a877 6445 * Try the public key supplied in the configuration.
6446 *
6447 * First, offer the public blob to see if the server is
6448 * willing to accept it.
65a22376 6449 */
d8baa528 6450 pub_blob =
9a30e26b 6451 (unsigned char *)ssh2_userkey_loadpub(&ssh->cfg.keyfile,
d8baa528 6452 &algorithm,
222d54dc 6453 &pub_blob_len,
6454 NULL);
1408a877 6455 if (pub_blob) {
ff3187f6 6456 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6457 ssh2_pkt_addstring(s->pktout, s->username);
6458 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6459 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6460 ssh2_pkt_addbool(s->pktout, FALSE); /* no signature included */
6461 ssh2_pkt_addstring(s->pktout, algorithm);
6462 ssh2_pkt_addstring_start(s->pktout);
6463 ssh2_pkt_addstring_data(s->pktout, (char *)pub_blob,
d8baa528 6464 pub_blob_len);
ff3187f6 6465 ssh2_pkt_send(ssh, s->pktout);
a03c9f9c 6466 logevent("Offered public key");
1408a877 6467
ff3187f6 6468 crWaitUntilV(pktin);
6469 if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
51470298 6470 s->gotit = TRUE;
6471 s->type = AUTH_TYPE_PUBLICKEY_OFFER_LOUD;
32874aea 6472 continue; /* key refused; give up on it */
1408a877 6473 }
65a22376 6474
1408a877 6475 logevent("Offer of public key accepted");
65a22376 6476 /*
1408a877 6477 * Actually attempt a serious authentication using
6478 * the key.
65a22376 6479 */
9a30e26b 6480 if (ssh2_userkey_encrypted(&ssh->cfg.keyfile, &comment)) {
51470298 6481 sprintf(s->pwprompt,
32874aea 6482 "Passphrase for key \"%.100s\": ",
6483 comment);
51470298 6484 s->need_pw = TRUE;
1408a877 6485 } else {
51470298 6486 s->need_pw = FALSE;
1408a877 6487 }
4e520718 6488 if (flags & FLAG_VERBOSE) {
6489 c_write_str(ssh, "Authenticating with public key \"");
6490 c_write_str(ssh, comment);
6491 c_write_str(ssh, "\"\r\n");
6492 }
51470298 6493 s->method = AUTH_PUBLICKEY_FILE;
65a22376 6494 }
1408a877 6495 }
6496
6f64ce13 6497 if (!s->method && s->can_keyb_inter && !s->kbd_inter_refused &&
6498 !s->kbd_inter_running) {
51470298 6499 s->method = AUTH_KEYBOARD_INTERACTIVE;
6500 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
af659722 6501
51470298 6502 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6503 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
00db133f 6504
ff3187f6 6505 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6506 ssh2_pkt_addstring(s->pktout, s->username);
6507 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6508 ssh2_pkt_addstring(s->pktout, "keyboard-interactive"); /* method */
6509 ssh2_pkt_addstring(s->pktout, ""); /* lang */
6510 ssh2_pkt_addstring(s->pktout, "");
6511 ssh2_pkt_send(ssh, s->pktout);
6512
6513 crWaitUntilV(pktin);
6514 if (pktin->type != SSH2_MSG_USERAUTH_INFO_REQUEST) {
6515 if (pktin->type == SSH2_MSG_USERAUTH_FAILURE)
51470298 6516 s->gotit = TRUE;
af659722 6517 logevent("Keyboard-interactive authentication refused");
51470298 6518 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET;
6ac3a551 6519 s->kbd_inter_refused = TRUE; /* don't try it again */
af659722 6520 continue;
6521 }
6522
51470298 6523 s->kbd_inter_running = TRUE;
6524 s->curr_prompt = 0;
af659722 6525 }
6526
51470298 6527 if (s->kbd_inter_running) {
6528 s->method = AUTH_KEYBOARD_INTERACTIVE;
6529 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
af659722 6530
51470298 6531 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6532 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
00db133f 6533
51470298 6534 if (s->curr_prompt == 0) {
45068b27 6535 /*
6536 * We've got a fresh USERAUTH_INFO_REQUEST.
6537 * Display header data, and start going through
6538 * the prompts.
6539 */
6540 char *name, *inst, *lang;
6541 int name_len, inst_len, lang_len;
6542
ff3187f6 6543 ssh_pkt_getstring(pktin, &name, &name_len);
6544 ssh_pkt_getstring(pktin, &inst, &inst_len);
6545 ssh_pkt_getstring(pktin, &lang, &lang_len);
45068b27 6546 if (name_len > 0) {
51470298 6547 c_write_untrusted(ssh, name, name_len);
6548 c_write_str(ssh, "\r\n");
45068b27 6549 }
6550 if (inst_len > 0) {
51470298 6551 c_write_untrusted(ssh, inst, inst_len);
6552 c_write_str(ssh, "\r\n");
45068b27 6553 }
ff3187f6 6554 s->num_prompts = ssh_pkt_getuint32(pktin);
45068b27 6555 }
af659722 6556
45068b27 6557 /*
6558 * If there are prompts remaining in the packet,
6559 * display one and get a response.
6560 */
51470298 6561 if (s->curr_prompt < s->num_prompts) {
45068b27 6562 char *prompt;
6563 int prompt_len;
af659722 6564
ff3187f6 6565 ssh_pkt_getstring(pktin, &prompt, &prompt_len);
45068b27 6566 if (prompt_len > 0) {
85fdbe25 6567 static const char trunc[] = "<prompt truncated>: ";
6568 static const int prlen = sizeof(s->pwprompt) -
6569 lenof(trunc);
6570 if (prompt_len > prlen) {
6571 memcpy(s->pwprompt, prompt, prlen);
6572 strcpy(s->pwprompt + prlen, trunc);
6573 } else {
6574 memcpy(s->pwprompt, prompt, prompt_len);
6575 s->pwprompt[prompt_len] = '\0';
6576 }
45068b27 6577 } else {
51470298 6578 strcpy(s->pwprompt,
45068b27 6579 "<server failed to send prompt>: ");
6580 }
ff3187f6 6581 s->echo = ssh2_pkt_getbool(pktin);
51470298 6582 s->need_pw = TRUE;
45068b27 6583 } else
51470298 6584 s->need_pw = FALSE;
af659722 6585 }
6586
51470298 6587 if (!s->method && s->can_passwd) {
6588 s->method = AUTH_PASSWORD;
6589 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6590 ssh->pkt_ctx |= SSH2_PKTCTX_PASSWORD;
6591 sprintf(s->pwprompt, "%.90s@%.90s's password: ", s->username,
6592 ssh->savedhost);
6593 s->need_pw = TRUE;
1408a877 6594 }
6595
51470298 6596 if (s->need_pw) {
fa17a66e 6597 if (ssh_get_line) {
51470298 6598 if (!ssh_get_line(s->pwprompt, s->password,
6599 sizeof(s->password), TRUE)) {
1408a877 6600 /*
fa17a66e 6601 * get_line failed to get a password (for
6602 * example because one was supplied on the
6603 * command line which has already failed to
6604 * work). Terminate.
1408a877 6605 */
ff3187f6 6606 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
6607 ssh2_pkt_adduint32(s->pktout,SSH2_DISCONNECT_BY_APPLICATION);
6608 ssh2_pkt_addstring(s->pktout, "No more passwords available"
51470298 6609 " to try");
ff3187f6 6610 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
590f6a5f 6611 ssh2_pkt_send_noqueue(ssh, s->pktout);
247308b5 6612 logevent("Unable to authenticate");
a8327734 6613 connection_fatal(ssh->frontend,
6614 "Unable to authenticate");
3bb2f322 6615 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 6616 crStopV;
1408a877 6617 }
6618 } else {
51470298 6619 int ret; /* need not be saved across crReturn */
6620 c_write_untrusted(ssh, s->pwprompt, strlen(s->pwprompt));
6621 ssh->send_ok = 1;
1408a877 6622
51470298 6623 setup_userpass_input(ssh, s->password,
6624 sizeof(s->password), s->echo);
0405e71f 6625 do {
ff3187f6 6626 crWaitUntilV(!pktin);
51470298 6627 ret = process_userpass_input(ssh, in, inlen);
0405e71f 6628 } while (ret == 0);
6629 if (ret < 0)
6630 cleanup_exit(0);
51470298 6631 c_write_str(ssh, "\r\n");
65a22376 6632 }
65a22376 6633 }
65a22376 6634
51470298 6635 if (s->method == AUTH_PUBLICKEY_FILE) {
1408a877 6636 /*
6637 * We have our passphrase. Now try the actual authentication.
6638 */
6639 struct ssh2_userkey *key;
222d54dc 6640 const char *error = NULL;
65a22376 6641
222d54dc 6642 key = ssh2_load_userkey(&ssh->cfg.keyfile, s->password,
6643 &error);
1408a877 6644 if (key == SSH2_WRONG_PASSPHRASE || key == NULL) {
6645 if (key == SSH2_WRONG_PASSPHRASE) {
51470298 6646 c_write_str(ssh, "Wrong passphrase\r\n");
6647 s->tried_pubkey_config = FALSE;
1408a877 6648 } else {
222d54dc 6649 c_write_str(ssh, "Unable to load private key (");
6650 c_write_str(ssh, error);
6651 c_write_str(ssh, ")\r\n");
51470298 6652 s->tried_pubkey_config = TRUE;
1408a877 6653 }
6654 /* Send a spurious AUTH_NONE to return to the top. */
ff3187f6 6655 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6656 ssh2_pkt_addstring(s->pktout, s->username);
6657 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6658 ssh2_pkt_addstring(s->pktout, "none"); /* method */
6659 ssh2_pkt_send(ssh, s->pktout);
51470298 6660 s->type = AUTH_TYPE_NONE;
1408a877 6661 } else {
1dd353b5 6662 unsigned char *pkblob, *sigblob, *sigdata;
6663 int pkblob_len, sigblob_len, sigdata_len;
dda87a28 6664 int p;
65a22376 6665
1408a877 6666 /*
6667 * We have loaded the private key and the server
6668 * has announced that it's willing to accept it.
6669 * Hallelujah. Generate a signature and send it.
6670 */
ff3187f6 6671 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6672 ssh2_pkt_addstring(s->pktout, s->username);
6673 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6674 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6675 ssh2_pkt_addbool(s->pktout, TRUE);
6676 ssh2_pkt_addstring(s->pktout, key->alg->name);
1dd353b5 6677 pkblob = key->alg->public_blob(key->data, &pkblob_len);
ff3187f6 6678 ssh2_pkt_addstring_start(s->pktout);
6679 ssh2_pkt_addstring_data(s->pktout, (char *)pkblob, pkblob_len);
1408a877 6680
6681 /*
6682 * The data to be signed is:
6683 *
6684 * string session-id
6685 *
6686 * followed by everything so far placed in the
6687 * outgoing packet.
6688 */
ff3187f6 6689 sigdata_len = s->pktout->length - 5 + 4 + 20;
dda87a28 6690 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
6691 sigdata_len -= 4;
92d60585 6692 sigdata = snewn(sigdata_len, unsigned char);
dda87a28 6693 p = 0;
6694 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
6695 PUT_32BIT(sigdata+p, 20);
6696 p += 4;
6697 }
6698 memcpy(sigdata+p, ssh->v2_session_id, 20); p += 20;
ff3187f6 6699 memcpy(sigdata+p, s->pktout->data + 5,
6700 s->pktout->length - 5);
6701 p += s->pktout->length - 5;
dda87a28 6702 assert(p == sigdata_len);
d8baa528 6703 sigblob = key->alg->sign(key->data, (char *)sigdata,
1dd353b5 6704 sigdata_len, &sigblob_len);
ff3187f6 6705 ssh2_add_sigblob(ssh, s->pktout, pkblob, pkblob_len,
1dd353b5 6706 sigblob, sigblob_len);
6707 sfree(pkblob);
6708 sfree(sigblob);
1408a877 6709 sfree(sigdata);
6710
ff3187f6 6711 ssh2_pkt_send(ssh, s->pktout);
51470298 6712 s->type = AUTH_TYPE_PUBLICKEY;
75374b2f 6713 key->alg->freekey(key->data);
1408a877 6714 }
51470298 6715 } else if (s->method == AUTH_PASSWORD) {
65a22376 6716 /*
1408a877 6717 * We send the password packet lumped tightly together with
6718 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
6719 * string long enough to make the total length of the two
6720 * packets constant. This should ensure that a passive
6721 * listener doing traffic analyis can't work out the length
6722 * of the password.
6723 *
6724 * For this to work, we need an assumption about the
6725 * maximum length of the password packet. I think 256 is
6726 * pretty conservative. Anyone using a password longer than
6727 * that probably doesn't have much to worry about from
6728 * people who find out how long their password is!
65a22376 6729 */
ff3187f6 6730 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6731 ssh2_pkt_addstring(s->pktout, s->username);
6732 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6733 ssh2_pkt_addstring(s->pktout, "password");
6734 ssh2_pkt_addbool(s->pktout, FALSE);
6735 dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
6736 ssh2_pkt_addstring(s->pktout, s->password);
1409c1b3 6737 memset(s->password, 0, sizeof(s->password));
ff3187f6 6738 end_log_omission(ssh, s->pktout);
6739 ssh2_pkt_defer(ssh, s->pktout);
65a22376 6740 /*
1408a877 6741 * We'll include a string that's an exact multiple of the
6742 * cipher block size. If the cipher is NULL for some
6743 * reason, we don't do this trick at all because we gain
6744 * nothing by it.
65a22376 6745 */
51470298 6746 if (ssh->cscipher) {
32874aea 6747 int stringlen, i;
6748
51470298 6749 stringlen = (256 - ssh->deferred_len);
6750 stringlen += ssh->cscipher->blksize - 1;
6751 stringlen -= (stringlen % ssh->cscipher->blksize);
6752 if (ssh->cscomp) {
32874aea 6753 /*
6754 * Temporarily disable actual compression,
6755 * so we can guarantee to get this string
6756 * exactly the length we want it. The
6757 * compression-disabling routine should
6758 * return an integer indicating how many
6759 * bytes we should adjust our string length
6760 * by.
6761 */
5366aed8 6762 stringlen -=
6763 ssh->cscomp->disable_compression(ssh->cs_comp_ctx);
32874aea 6764 }
ff3187f6 6765 s->pktout = ssh2_pkt_init(SSH2_MSG_IGNORE);
6766 ssh2_pkt_addstring_start(s->pktout);
6e9e9520 6767 for (i = 0; i < stringlen; i++) {
32874aea 6768 char c = (char) random_byte();
ff3187f6 6769 ssh2_pkt_addstring_data(s->pktout, &c, 1);
65a22376 6770 }
ff3187f6 6771 ssh2_pkt_defer(ssh, s->pktout);
65a22376 6772 }
51470298 6773 ssh_pkt_defersend(ssh);
0d43337a 6774 logevent("Sent password");
51470298 6775 s->type = AUTH_TYPE_PASSWORD;
6776 } else if (s->method == AUTH_KEYBOARD_INTERACTIVE) {
6777 if (s->curr_prompt == 0) {
ff3187f6 6778 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE);
6779 ssh2_pkt_adduint32(s->pktout, s->num_prompts);
45068b27 6780 }
51470298 6781 if (s->need_pw) { /* only add pw if we just got one! */
ff3187f6 6782 dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
6783 ssh2_pkt_addstring(s->pktout, s->password);
51470298 6784 memset(s->password, 0, sizeof(s->password));
ff3187f6 6785 end_log_omission(ssh, s->pktout);
51470298 6786 s->curr_prompt++;
45068b27 6787 }
51470298 6788 if (s->curr_prompt >= s->num_prompts) {
ff3187f6 6789 ssh2_pkt_send(ssh, s->pktout);
45068b27 6790 } else {
6791 /*
6792 * If there are prompts remaining, we set
6793 * `gotit' so that we won't attempt to get
6794 * another packet. Then we go back round the
6795 * loop and will end up retrieving another
6796 * prompt out of the existing packet. Funky or
6797 * what?
6798 */
51470298 6799 s->gotit = TRUE;
45068b27 6800 }
51470298 6801 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
1408a877 6802 } else {
51470298 6803 c_write_str(ssh, "No supported authentication methods"
6804 " left to try!\r\n");
6805 logevent("No supported authentications offered."
6806 " Disconnecting");
ff3187f6 6807 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
6808 ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
6809 ssh2_pkt_addstring(s->pktout, "No supported authentication"
51470298 6810 " methods available");
ff3187f6 6811 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
590f6a5f 6812 ssh2_pkt_send_noqueue(ssh, s->pktout);
3bb2f322 6813 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 6814 crStopV;
65a22376 6815 }
65a22376 6816 }
51470298 6817 } while (!s->we_are_in);
7cca0d81 6818
6819 /*
6820 * Now we're authenticated for the connection protocol. The
6821 * connection protocol will automatically have started at this
6822 * point; there's no need to send SERVICE_REQUEST.
6823 */
6824
0ed48730 6825 ssh->channels = newtree234(ssh_channelcmp);
6826
7cca0d81 6827 /*
b09eaa88 6828 * Set up handlers for some connection protocol messages, so we
6829 * don't have to handle them repeatedly in this coroutine.
6830 */
6831 ssh->packet_dispatch[SSH2_MSG_CHANNEL_WINDOW_ADJUST] =
6832 ssh2_msg_channel_window_adjust;
51df0ab5 6833 ssh->packet_dispatch[SSH2_MSG_GLOBAL_REQUEST] =
6834 ssh2_msg_global_request;
b09eaa88 6835
6836 /*
0ed48730 6837 * Create the main session channel.
7cca0d81 6838 */
0ed48730 6839 if (!ssh->cfg.ssh_no_shell) {
6840 ssh->mainchan = snew(struct ssh_channel);
6841 ssh->mainchan->ssh = ssh;
6842 ssh->mainchan->localid = alloc_channel_id(ssh);
ff3187f6 6843 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
6844 ssh2_pkt_addstring(s->pktout, "session");
6845 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->localid);
0ed48730 6846 ssh->mainchan->v.v2.locwindow = OUR_V2_WINSIZE;
ff3187f6 6847 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->v.v2.locwindow);/* our window size */
6848 ssh2_pkt_adduint32(s->pktout, 0x4000UL); /* our max pkt size */
6849 ssh2_pkt_send(ssh, s->pktout);
6850 crWaitUntilV(pktin);
6851 if (pktin->type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
0ed48730 6852 bombout(("Server refused to open a session"));
6853 crStopV;
6854 /* FIXME: error data comes back in FAILURE packet */
6855 }
ff3187f6 6856 if (ssh_pkt_getuint32(pktin) != ssh->mainchan->localid) {
0ed48730 6857 bombout(("Server's channel confirmation cited wrong channel"));
6858 crStopV;
6859 }
ff3187f6 6860 ssh->mainchan->remoteid = ssh_pkt_getuint32(pktin);
0ed48730 6861 ssh->mainchan->type = CHAN_MAINSESSION;
6862 ssh->mainchan->closes = 0;
ff3187f6 6863 ssh->mainchan->v.v2.remwindow = ssh_pkt_getuint32(pktin);
6864 ssh->mainchan->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin);
0ed48730 6865 bufchain_init(&ssh->mainchan->v.v2.outbuffer);
6866 add234(ssh->channels, ssh->mainchan);
62638676 6867 update_specials_menu(ssh->frontend);
0ed48730 6868 logevent("Opened channel for session");
6869 } else
6870 ssh->mainchan = NULL;
7cca0d81 6871
6872 /*
51df0ab5 6873 * Now we have a channel, make dispatch table entries for
6874 * general channel-based messages.
6875 */
6876 ssh->packet_dispatch[SSH2_MSG_CHANNEL_DATA] =
6877 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EXTENDED_DATA] =
6878 ssh2_msg_channel_data;
6879 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EOF] = ssh2_msg_channel_eof;
6880 ssh->packet_dispatch[SSH2_MSG_CHANNEL_CLOSE] = ssh2_msg_channel_close;
6881 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION] =
6882 ssh2_msg_channel_open_confirmation;
6883 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_FAILURE] =
6884 ssh2_msg_channel_open_failure;
6885 ssh->packet_dispatch[SSH2_MSG_CHANNEL_REQUEST] =
6886 ssh2_msg_channel_request;
6887 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN] =
6888 ssh2_msg_channel_open;
6889
6890 /*
783415f8 6891 * Potentially enable X11 forwarding.
6892 */
0ed48730 6893 if (ssh->mainchan && ssh->cfg.x11_forward) {
32874aea 6894 char proto[20], data[64];
6895 logevent("Requesting X11 forwarding");
302121de 6896 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
86916870 6897 data, sizeof(data), ssh->cfg.x11_auth);
6898 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
ff3187f6 6899 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
6900 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
6901 ssh2_pkt_addstring(s->pktout, "x11-req");
6902 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
6903 ssh2_pkt_addbool(s->pktout, 0); /* many connections */
6904 ssh2_pkt_addstring(s->pktout, proto);
6905 ssh2_pkt_addstring(s->pktout, data);
6906 ssh2_pkt_adduint32(s->pktout, x11_get_screen_number(ssh->cfg.x11_display));
6907 ssh2_pkt_send(ssh, s->pktout);
32874aea 6908
b09eaa88 6909 crWaitUntilV(pktin);
32874aea 6910
ff3187f6 6911 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
6912 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 6913 bombout(("Unexpected response to X11 forwarding request:"
ff3187f6 6914 " packet type %d", pktin->type));
7ffdbc1a 6915 crStopV;
32874aea 6916 }
6917 logevent("X11 forwarding refused");
6918 } else {
6919 logevent("X11 forwarding enabled");
51470298 6920 ssh->X11_fwd_enabled = TRUE;
32874aea 6921 }
783415f8 6922 }
6923
6924 /*
bc240b21 6925 * Enable port forwardings.
6926 */
06fadff5 6927 ssh_setup_portfwd(ssh, &ssh->cfg);
bc240b21 6928
6929 /*
36c2a3e9 6930 * Potentially enable agent forwarding.
6931 */
0ed48730 6932 if (ssh->mainchan && ssh->cfg.agentfwd && agent_exists()) {
32874aea 6933 logevent("Requesting OpenSSH-style agent forwarding");
ff3187f6 6934 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
6935 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
6936 ssh2_pkt_addstring(s->pktout, "auth-agent-req@openssh.com");
6937 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
6938 ssh2_pkt_send(ssh, s->pktout);
32874aea 6939
b09eaa88 6940 crWaitUntilV(pktin);
32874aea 6941
ff3187f6 6942 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
6943 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 6944 bombout(("Unexpected response to agent forwarding request:"
ff3187f6 6945 " packet type %d", pktin->type));
7ffdbc1a 6946 crStopV;
32874aea 6947 }
6948 logevent("Agent forwarding refused");
6949 } else {
6950 logevent("Agent forwarding enabled");
51470298 6951 ssh->agentfwd_enabled = TRUE;
32874aea 6952 }
36c2a3e9 6953 }
6954
6955 /*
7cca0d81 6956 * Now allocate a pty for the session.
6957 */
0ed48730 6958 if (ssh->mainchan && !ssh->cfg.nopty) {
a5dd8467 6959 /* Unpick the terminal-speed string. */
6960 /* XXX perhaps we should allow no speeds to be sent. */
db219738 6961 ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
6962 sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
a5dd8467 6963 /* Build the pty request. */
ff3187f6 6964 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
6965 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid); /* recipient channel */
6966 ssh2_pkt_addstring(s->pktout, "pty-req");
6967 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
6968 ssh2_pkt_addstring(s->pktout, ssh->cfg.termtype);
6969 ssh2_pkt_adduint32(s->pktout, ssh->term_width);
6970 ssh2_pkt_adduint32(s->pktout, ssh->term_height);
6971 ssh2_pkt_adduint32(s->pktout, 0); /* pixel width */
6972 ssh2_pkt_adduint32(s->pktout, 0); /* pixel height */
6973 ssh2_pkt_addstring_start(s->pktout);
6974 ssh2_pkt_addbyte(s->pktout, 128); /* TTY_OP_ISPEED */
6975 ssh2_pkt_adduint32(s->pktout, ssh->ispeed);
6976 ssh2_pkt_addbyte(s->pktout, 129); /* TTY_OP_OSPEED */
6977 ssh2_pkt_adduint32(s->pktout, ssh->ospeed);
6978 ssh2_pkt_addstring_data(s->pktout, "\0", 1); /* TTY_OP_END */
6979 ssh2_pkt_send(ssh, s->pktout);
51470298 6980 ssh->state = SSH_STATE_INTERMED;
32874aea 6981
b09eaa88 6982 crWaitUntilV(pktin);
32874aea 6983
ff3187f6 6984 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
6985 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 6986 bombout(("Unexpected response to pty request:"
ff3187f6 6987 " packet type %d", pktin->type));
7ffdbc1a 6988 crStopV;
32874aea 6989 }
51470298 6990 c_write_str(ssh, "Server refused to allocate pty\r\n");
6991 ssh->editing = ssh->echoing = 1;
32874aea 6992 } else {
a5dd8467 6993 logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
db219738 6994 ssh->ospeed, ssh->ispeed);
32874aea 6995 }
0965bee0 6996 } else {
51470298 6997 ssh->editing = ssh->echoing = 1;
7cca0d81 6998 }
6999
7000 /*
73feed4f 7001 * Send environment variables.
7002 *
7003 * Simplest thing here is to send all the requests at once, and
7004 * then wait for a whole bunch of successes or failures.
7005 */
7006 if (ssh->mainchan && *ssh->cfg.environmt) {
7007 char *e = ssh->cfg.environmt;
7008 char *var, *varend, *val;
7009
7010 s->num_env = 0;
7011
7012 while (*e) {
7013 var = e;
7014 while (*e && *e != '\t') e++;
7015 varend = e;
7016 if (*e == '\t') e++;
7017 val = e;
7018 while (*e) e++;
7019 e++;
7020
ff3187f6 7021 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7022 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
7023 ssh2_pkt_addstring(s->pktout, "env");
7024 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7025 ssh2_pkt_addstring_start(s->pktout);
7026 ssh2_pkt_addstring_data(s->pktout, var, varend-var);
7027 ssh2_pkt_addstring(s->pktout, val);
7028 ssh2_pkt_send(ssh, s->pktout);
73feed4f 7029
7030 s->num_env++;
7031 }
7032
7033 logeventf(ssh, "Sent %d environment variables", s->num_env);
7034
7035 s->env_ok = 0;
7036 s->env_left = s->num_env;
7037
7038 while (s->env_left > 0) {
b09eaa88 7039 crWaitUntilV(pktin);
73feed4f 7040
ff3187f6 7041 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
7042 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
73feed4f 7043 bombout(("Unexpected response to environment request:"
ff3187f6 7044 " packet type %d", pktin->type));
73feed4f 7045 crStopV;
7046 }
7047 } else {
7048 s->env_ok++;
7049 }
7050
7051 s->env_left--;
7052 }
7053
7054 if (s->env_ok == s->num_env) {
7055 logevent("All environment variables successfully set");
7056 } else if (s->env_ok == 0) {
7057 logevent("All environment variables refused");
7058 c_write_str(ssh, "Server refused to set environment variables\r\n");
7059 } else {
7060 logeventf(ssh, "%d environment variables refused",
7061 s->num_env - s->env_ok);
7062 c_write_str(ssh, "Server refused to set all environment variables\r\n");
7063 }
7064 }
7065
7066 /*
fd5e5847 7067 * Start a shell or a remote command. We may have to attempt
7068 * this twice if the config data has provided a second choice
7069 * of command.
7cca0d81 7070 */
0ed48730 7071 if (ssh->mainchan) while (1) {
fd5e5847 7072 int subsys;
7073 char *cmd;
7074
51470298 7075 if (ssh->fallback_cmd) {
86916870 7076 subsys = ssh->cfg.ssh_subsys2;
7077 cmd = ssh->cfg.remote_cmd_ptr2;
fd5e5847 7078 } else {
86916870 7079 subsys = ssh->cfg.ssh_subsys;
7080 cmd = ssh->cfg.remote_cmd_ptr;
fd5e5847 7081 }
7082
ff3187f6 7083 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7084 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid); /* recipient channel */
fd5e5847 7085 if (subsys) {
ff3187f6 7086 ssh2_pkt_addstring(s->pktout, "subsystem");
7087 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7088 ssh2_pkt_addstring(s->pktout, cmd);
fd5e5847 7089 } else if (*cmd) {
ff3187f6 7090 ssh2_pkt_addstring(s->pktout, "exec");
7091 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7092 ssh2_pkt_addstring(s->pktout, cmd);
fd5e5847 7093 } else {
ff3187f6 7094 ssh2_pkt_addstring(s->pktout, "shell");
7095 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
32874aea 7096 }
ff3187f6 7097 ssh2_pkt_send(ssh, s->pktout);
b09eaa88 7098
7099 crWaitUntilV(pktin);
7100
ff3187f6 7101 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
7102 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 7103 bombout(("Unexpected response to shell/command request:"
ff3187f6 7104 " packet type %d", pktin->type));
7ffdbc1a 7105 crStopV;
fd5e5847 7106 }
7107 /*
7108 * We failed to start the command. If this is the
7109 * fallback command, we really are finished; if it's
7110 * not, and if the fallback command exists, try falling
7111 * back to it before complaining.
7112 */
86916870 7113 if (!ssh->fallback_cmd && ssh->cfg.remote_cmd_ptr2 != NULL) {
fd5e5847 7114 logevent("Primary command failed; attempting fallback");
51470298 7115 ssh->fallback_cmd = TRUE;
fd5e5847 7116 continue;
7117 }
6b5cf8b4 7118 bombout(("Server refused to start a shell/command"));
7ffdbc1a 7119 crStopV;
fd5e5847 7120 } else {
7121 logevent("Started a shell/command");
32874aea 7122 }
fd5e5847 7123 break;
7cca0d81 7124 }
7125
51470298 7126 ssh->state = SSH_STATE_SESSION;
7127 if (ssh->size_needed)
7128 ssh_size(ssh, ssh->term_width, ssh->term_height);
7129 if (ssh->eof_needed)
7130 ssh_special(ssh, TS_EOF);
6e48c3fe 7131
7cca0d81 7132 /*
7133 * Transfer data!
7134 */
b9d7bcad 7135 if (ssh->ldisc)
7136 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
0ed48730 7137 if (ssh->mainchan)
7138 ssh->send_ok = 1;
7cca0d81 7139 while (1) {
e5574168 7140 crReturnV;
51470298 7141 s->try_send = FALSE;
ff3187f6 7142 if (pktin) {
2b7540a7 7143
51df0ab5 7144 /*
7145 * _All_ the connection-layer packets we expect to
7146 * receive are now handled by the dispatch table.
7147 * Anything that reaches here must be bogus.
7148 */
32874aea 7149
51df0ab5 7150 bombout(("Strange packet received: type %d", pktin->type));
7151 crStopV;
0ed48730 7152 } else if (ssh->mainchan) {
32874aea 7153 /*
7154 * We have spare data. Add it to the channel buffer.
7155 */
d8baa528 7156 ssh2_add_channel_data(ssh->mainchan, (char *)in, inlen);
51470298 7157 s->try_send = TRUE;
32874aea 7158 }
51470298 7159 if (s->try_send) {
32874aea 7160 int i;
7161 struct ssh_channel *c;
7162 /*
7163 * Try to send data on all channels if we can.
7164 */
51470298 7165 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
a6253970 7166 int bufsize;
7167 if (c->closes)
7168 continue; /* don't send on closing channels */
7169 bufsize = ssh2_try_send(c);
5471d09a 7170 if (bufsize == 0) {
7171 switch (c->type) {
7172 case CHAN_MAINSESSION:
7173 /* stdin need not receive an unthrottle
7174 * notification since it will be polled */
7175 break;
7176 case CHAN_X11:
7177 x11_unthrottle(c->u.x11.s);
7178 break;
7179 case CHAN_AGENT:
7180 /* agent sockets are request/response and need no
7181 * buffer management */
7182 break;
7183 case CHAN_SOCKDATA:
7184 pfd_unthrottle(c->u.pfd.s);
7185 break;
7186 }
7187 }
7188 }
7cca0d81 7189 }
e5574168 7190 }
7191
7192 crFinishV;
7193}
7194
7195/*
b09eaa88 7196 * Handlers for SSH2 messages that might arrive at any moment.
7197 */
7198void ssh2_msg_disconnect(Ssh ssh, struct Packet *pktin)
7199{
7200 /* log reason code in disconnect message */
7201 char *buf, *msg;
7202 int nowlen, reason, msglen;
7203
7204 reason = ssh_pkt_getuint32(pktin);
7205 ssh_pkt_getstring(pktin, &msg, &msglen);
7206
7207 if (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) {
7208 buf = dupprintf("Received disconnect message (%s)",
7209 ssh2_disconnect_reasons[reason]);
7210 } else {
7211 buf = dupprintf("Received disconnect message (unknown"
7212 " type %d)", reason);
7213 }
7214 logevent(buf);
7215 sfree(buf);
7216 buf = dupprintf("Disconnection message text: %n%.*s",
7217 &nowlen, msglen, msg);
7218 logevent(buf);
7219 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
7220 reason,
7221 (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) ?
7222 ssh2_disconnect_reasons[reason] : "unknown",
7223 buf+nowlen));
7224 sfree(buf);
7225}
7226
7227void ssh2_msg_debug(Ssh ssh, struct Packet *pktin)
7228{
7229 /* log the debug message */
7230 char *buf, *msg;
7231 int msglen;
7232 int always_display;
7233
7234 /* XXX maybe we should actually take notice of this */
7235 always_display = ssh2_pkt_getbool(pktin);
7236 ssh_pkt_getstring(pktin, &msg, &msglen);
7237
7238 buf = dupprintf("Remote debug message: %.*s", msglen, msg);
7239 logevent(buf);
7240 sfree(buf);
7241}
7242
7243void ssh2_msg_something_unimplemented(Ssh ssh, struct Packet *pktin)
7244{
7245 struct Packet *pktout;
7246 pktout = ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED);
7247 ssh2_pkt_adduint32(pktout, pktin->sequence);
7248 /*
7249 * UNIMPLEMENTED messages MUST appear in the same order as the
7250 * messages they respond to. Hence, never queue them.
7251 */
7252 ssh2_pkt_send_noqueue(ssh, pktout);
7253}
7254
7255/*
7cca0d81 7256 * Handle the top-level SSH2 protocol.
7257 */
b09eaa88 7258static void ssh2_protocol_setup(Ssh ssh)
7259{
7260 int i;
7261
7262 /*
7263 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
7264 */
7265 for (i = 0; i < 256; i++)
7266 ssh->packet_dispatch[i] = ssh2_msg_something_unimplemented;
7267
7268 /*
7269 * Any message we actually understand, we set to NULL so that
7270 * the coroutines will get it.
7271 */
7272 ssh->packet_dispatch[SSH2_MSG_UNIMPLEMENTED] = NULL;
7273 ssh->packet_dispatch[SSH2_MSG_SERVICE_REQUEST] = NULL;
7274 ssh->packet_dispatch[SSH2_MSG_SERVICE_ACCEPT] = NULL;
7275 ssh->packet_dispatch[SSH2_MSG_KEXINIT] = NULL;
7276 ssh->packet_dispatch[SSH2_MSG_NEWKEYS] = NULL;
7277 ssh->packet_dispatch[SSH2_MSG_KEXDH_INIT] = NULL;
7278 ssh->packet_dispatch[SSH2_MSG_KEXDH_REPLY] = NULL;
7279 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
7280 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
7281 ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_INIT] = NULL;
7282 ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REPLY] = NULL;
7283 ssh->packet_dispatch[SSH2_MSG_USERAUTH_REQUEST] = NULL;
7284 ssh->packet_dispatch[SSH2_MSG_USERAUTH_FAILURE] = NULL;
7285 ssh->packet_dispatch[SSH2_MSG_USERAUTH_SUCCESS] = NULL;
7286 ssh->packet_dispatch[SSH2_MSG_USERAUTH_BANNER] = NULL;
7287 ssh->packet_dispatch[SSH2_MSG_USERAUTH_PK_OK] = NULL;
7288 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
7289 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
7290 ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_RESPONSE] = NULL;
7291 ssh->packet_dispatch[SSH2_MSG_GLOBAL_REQUEST] = NULL;
7292 ssh->packet_dispatch[SSH2_MSG_REQUEST_SUCCESS] = NULL;
7293 ssh->packet_dispatch[SSH2_MSG_REQUEST_FAILURE] = NULL;
7294 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN] = NULL;
7295 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION] = NULL;
7296 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_FAILURE] = NULL;
7297 ssh->packet_dispatch[SSH2_MSG_CHANNEL_WINDOW_ADJUST] = NULL;
7298 ssh->packet_dispatch[SSH2_MSG_CHANNEL_DATA] = NULL;
7299 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EXTENDED_DATA] = NULL;
7300 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EOF] = NULL;
7301 ssh->packet_dispatch[SSH2_MSG_CHANNEL_CLOSE] = NULL;
7302 ssh->packet_dispatch[SSH2_MSG_CHANNEL_REQUEST] = NULL;
7303 ssh->packet_dispatch[SSH2_MSG_CHANNEL_SUCCESS] = NULL;
7304 ssh->packet_dispatch[SSH2_MSG_CHANNEL_FAILURE] = NULL;
7305
7306 /*
7307 * These special message types we install handlers for.
7308 */
7309 ssh->packet_dispatch[SSH2_MSG_DISCONNECT] = ssh2_msg_disconnect;
7310 ssh->packet_dispatch[SSH2_MSG_IGNORE] = ssh_msg_ignore; /* shared with ssh1 */
7311 ssh->packet_dispatch[SSH2_MSG_DEBUG] = ssh2_msg_debug;
7312}
7313
9442dd57 7314static void ssh2_timer(void *ctx, long now)
7315{
7316 Ssh ssh = (Ssh)ctx;
7317
e6c1536e 7318 if (!ssh->kex_in_progress && ssh->cfg.ssh_rekey_time != 0 &&
9442dd57 7319 now - ssh->next_rekey >= 0) {
f382c87d 7320 do_ssh2_transport(ssh, "timeout", -1, NULL);
9442dd57 7321 }
7322}
7323
ff3187f6 7324static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen,
7325 struct Packet *pktin)
7cca0d81 7326{
b09eaa88 7327 if (ssh->state == SSH_STATE_CLOSED)
7328 return;
7329
9442dd57 7330 if (pktin) {
7331 ssh->incoming_data_size += pktin->encrypted_len;
7332 if (!ssh->kex_in_progress &&
d57f70af 7333 ssh->max_data_size != 0 &&
7334 ssh->incoming_data_size > ssh->max_data_size)
f382c87d 7335 do_ssh2_transport(ssh, "too much data received", -1, NULL);
9442dd57 7336 }
7337
b09eaa88 7338 if (pktin && ssh->packet_dispatch[pktin->type]) {
7339 ssh->packet_dispatch[pktin->type](ssh, pktin);
32874aea 7340 return;
b09eaa88 7341 }
7342
7343 if (!ssh->protocol_initial_phase_done ||
7344 (pktin && pktin->type >= 20 && pktin->type < 50)) {
7345 if (do_ssh2_transport(ssh, in, inlen, pktin) &&
7346 !ssh->protocol_initial_phase_done) {
7347 ssh->protocol_initial_phase_done = TRUE;
7348 /*
7349 * Allow authconn to initialise itself.
7350 */
7351 do_ssh2_authconn(ssh, NULL, 0, NULL);
7352 }
7353 } else {
7354 do_ssh2_authconn(ssh, in, inlen, pktin);
7355 }
7cca0d81 7356}
7357
7358/*
8df7a775 7359 * Called to set up the connection.
374330e2 7360 *
7361 * Returns an error message, or NULL on success.
374330e2 7362 */
cbe2d68f 7363static const char *ssh_init(void *frontend_handle, void **backend_handle,
7364 Config *cfg,
79bf227b 7365 char *host, int port, char **realhost, int nodelay,
7366 int keepalive)
32874aea 7367{
cbe2d68f 7368 const char *p;
51470298 7369 Ssh ssh;
7370
3d88e64d 7371 ssh = snew(struct ssh_tag);
86916870 7372 ssh->cfg = *cfg; /* STRUCTURE COPY */
125105d1 7373 ssh->version = 0; /* when not ready yet */
51470298 7374 ssh->s = NULL;
7375 ssh->cipher = NULL;
371e569c 7376 ssh->v1_cipher_ctx = NULL;
0183b242 7377 ssh->crcda_ctx = NULL;
51470298 7378 ssh->cscipher = NULL;
371e569c 7379 ssh->cs_cipher_ctx = NULL;
51470298 7380 ssh->sccipher = NULL;
371e569c 7381 ssh->sc_cipher_ctx = NULL;
51470298 7382 ssh->csmac = NULL;
a8327734 7383 ssh->cs_mac_ctx = NULL;
51470298 7384 ssh->scmac = NULL;
e0e1a00d 7385 ssh->sc_mac_ctx = NULL;
51470298 7386 ssh->cscomp = NULL;
5366aed8 7387 ssh->cs_comp_ctx = NULL;
51470298 7388 ssh->sccomp = NULL;
5366aed8 7389 ssh->sc_comp_ctx = NULL;
51470298 7390 ssh->kex = NULL;
389aa499 7391 ssh->kex_ctx = NULL;
51470298 7392 ssh->hostkey = NULL;
7393 ssh->exitcode = -1;
7394 ssh->state = SSH_STATE_PREPACKET;
7395 ssh->size_needed = FALSE;
7396 ssh->eof_needed = FALSE;
b9d7bcad 7397 ssh->ldisc = NULL;
a8327734 7398 ssh->logctx = NULL;
51470298 7399 ssh->deferred_send_data = NULL;
7400 ssh->deferred_len = 0;
7401 ssh->deferred_size = 0;
7402 ssh->fallback_cmd = 0;
7403 ssh->pkt_ctx = 0;
302121de 7404 ssh->x11auth = NULL;
be738459 7405 ssh->v1_compressing = FALSE;
51470298 7406 ssh->v2_outgoing_sequence = 0;
7407 ssh->ssh1_rdpkt_crstate = 0;
7408 ssh->ssh2_rdpkt_crstate = 0;
7409 ssh->do_ssh_init_crstate = 0;
7410 ssh->ssh_gotdata_crstate = 0;
b09eaa88 7411 ssh->do_ssh1_connection_crstate = 0;
51470298 7412 ssh->do_ssh1_login_crstate = 0;
7413 ssh->do_ssh2_transport_crstate = 0;
7414 ssh->do_ssh2_authconn_crstate = 0;
7415 ssh->do_ssh_init_state = NULL;
7416 ssh->do_ssh1_login_state = NULL;
7417 ssh->do_ssh2_transport_state = NULL;
7418 ssh->do_ssh2_authconn_state = NULL;
6571dbfd 7419 ssh->mainchan = NULL;
968d2d92 7420 ssh->throttled_all = 0;
7421 ssh->v1_stdout_throttling = 0;
590f6a5f 7422 ssh->queue = NULL;
7423 ssh->queuelen = ssh->queuesize = 0;
7424 ssh->queueing = FALSE;
06fadff5 7425 ssh->qhead = ssh->qtail = NULL;
e13bba36 7426 ssh->deferred_rekey_reason = NULL;
51470298 7427
7428 *backend_handle = ssh;
32874aea 7429
8f203108 7430#ifdef MSCRYPTOAPI
32874aea 7431 if (crypto_startup() == 0)
8f203108 7432 return "Microsoft high encryption pack not installed!";
7433#endif
374330e2 7434
51470298 7435 ssh->frontend = frontend_handle;
86916870 7436 ssh->term_width = ssh->cfg.width;
7437 ssh->term_height = ssh->cfg.height;
887035a5 7438
fabd1805 7439 ssh->channels = NULL;
7440 ssh->rportfwds = NULL;
f47a5ffb 7441 ssh->portfwds = NULL;
fabd1805 7442
51470298 7443 ssh->send_ok = 0;
7444 ssh->editing = 0;
7445 ssh->echoing = 0;
7446 ssh->v1_throttle_count = 0;
7447 ssh->overall_bufsize = 0;
7448 ssh->fallback_cmd = 0;
8df7a775 7449
3648d4c5 7450 ssh->protocol = NULL;
7451
b09eaa88 7452 ssh->protocol_initial_phase_done = FALSE;
7453
39934deb 7454 ssh->pinger = NULL;
7455
9442dd57 7456 ssh->incoming_data_size = ssh->outgoing_data_size =
7457 ssh->deferred_data_size = 0L;
d57f70af 7458 ssh->max_data_size = parse_blocksize(ssh->cfg.ssh_rekey_data);
9442dd57 7459 ssh->kex_in_progress = FALSE;
7460
79bf227b 7461 p = connect_to_host(ssh, host, port, realhost, nodelay, keepalive);
fb09bf1c 7462 if (p != NULL)
7463 return p;
374330e2 7464
5d17ccfc 7465 random_ref();
7466
374330e2 7467 return NULL;
7468}
7469
fabd1805 7470static void ssh_free(void *handle)
7471{
7472 Ssh ssh = (Ssh) handle;
7473 struct ssh_channel *c;
7474 struct ssh_rportfwd *pf;
7475
7476 if (ssh->v1_cipher_ctx)
7477 ssh->cipher->free_context(ssh->v1_cipher_ctx);
7478 if (ssh->cs_cipher_ctx)
7479 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
7480 if (ssh->sc_cipher_ctx)
7481 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
7482 if (ssh->cs_mac_ctx)
7483 ssh->csmac->free_context(ssh->cs_mac_ctx);
7484 if (ssh->sc_mac_ctx)
7485 ssh->scmac->free_context(ssh->sc_mac_ctx);
29b1d0b3 7486 if (ssh->cs_comp_ctx) {
7487 if (ssh->cscomp)
7488 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
7489 else
7490 zlib_compress_cleanup(ssh->cs_comp_ctx);
7491 }
7492 if (ssh->sc_comp_ctx) {
7493 if (ssh->sccomp)
7494 ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
7495 else
7496 zlib_decompress_cleanup(ssh->sc_comp_ctx);
7497 }
fabd1805 7498 if (ssh->kex_ctx)
7499 dh_cleanup(ssh->kex_ctx);
7500 sfree(ssh->savedhost);
7501
590f6a5f 7502 while (ssh->queuelen-- > 0)
7503 ssh_free_packet(ssh->queue[ssh->queuelen]);
7504 sfree(ssh->queue);
7505
06fadff5 7506 while (ssh->qhead) {
7507 struct queued_handler *qh = ssh->qhead;
7508 ssh->qhead = qh->next;
7509 sfree(ssh->qhead);
7510 }
7511 ssh->qhead = ssh->qtail = NULL;
7512
fabd1805 7513 if (ssh->channels) {
7514 while ((c = delpos234(ssh->channels, 0)) != NULL) {
7515 switch (c->type) {
7516 case CHAN_X11:
7517 if (c->u.x11.s != NULL)
7518 x11_close(c->u.x11.s);
7519 break;
7520 case CHAN_SOCKDATA:
7521 if (c->u.pfd.s != NULL)
7522 pfd_close(c->u.pfd.s);
7523 break;
7524 }
7525 sfree(c);
7526 }
7527 freetree234(ssh->channels);
cdb52705 7528 ssh->channels = NULL;
fabd1805 7529 }
7530
7531 if (ssh->rportfwds) {
7532 while ((pf = delpos234(ssh->rportfwds, 0)) != NULL)
7533 sfree(pf);
7534 freetree234(ssh->rportfwds);
cdb52705 7535 ssh->rportfwds = NULL;
fabd1805 7536 }
7537 sfree(ssh->deferred_send_data);
7538 if (ssh->x11auth)
7539 x11_free_auth(ssh->x11auth);
7540 sfree(ssh->do_ssh_init_state);
7541 sfree(ssh->do_ssh1_login_state);
7542 sfree(ssh->do_ssh2_transport_state);
7543 sfree(ssh->do_ssh2_authconn_state);
679539d7 7544 if (ssh->crcda_ctx) {
7545 crcda_free_context(ssh->crcda_ctx);
7546 ssh->crcda_ctx = NULL;
7547 }
fabd1805 7548 if (ssh->s)
36f94d1f 7549 ssh_do_close(ssh);
9442dd57 7550 expire_timer_context(ssh);
39934deb 7551 if (ssh->pinger)
7552 pinger_free(ssh->pinger);
ee50e8b6 7553 sfree(ssh);
5d17ccfc 7554
7555 random_unref();
fabd1805 7556}
7557
374330e2 7558/*
86916870 7559 * Reconfigure the SSH backend.
86916870 7560 */
7561static void ssh_reconfig(void *handle, Config *cfg)
7562{
7563 Ssh ssh = (Ssh) handle;
e13bba36 7564 char *rekeying = NULL, rekey_mandatory = FALSE;
e6c1536e 7565 unsigned long old_max_data_size;
7566
39934deb 7567 pinger_reconfig(ssh->pinger, &ssh->cfg, cfg);
fda2feb1 7568 ssh_setup_portfwd(ssh, cfg);
e6c1536e 7569
7570 if (ssh->cfg.ssh_rekey_time != cfg->ssh_rekey_time &&
7571 cfg->ssh_rekey_time != 0) {
7572 long new_next = ssh->last_rekey + cfg->ssh_rekey_time*60*TICKSPERSEC;
7573 long now = GETTICKCOUNT();
7574
7575 if (new_next - now < 0) {
f382c87d 7576 rekeying = "timeout shortened";
e6c1536e 7577 } else {
7578 ssh->next_rekey = schedule_timer(new_next - now, ssh2_timer, ssh);
7579 }
7580 }
7581
7582 old_max_data_size = ssh->max_data_size;
7583 ssh->max_data_size = parse_blocksize(cfg->ssh_rekey_data);
7584 if (old_max_data_size != ssh->max_data_size &&
7585 ssh->max_data_size != 0) {
7586 if (ssh->outgoing_data_size > ssh->max_data_size ||
7587 ssh->incoming_data_size > ssh->max_data_size)
f382c87d 7588 rekeying = "data limit lowered";
e6c1536e 7589 }
7590
e13bba36 7591 if (ssh->cfg.compression != cfg->compression) {
f382c87d 7592 rekeying = "compression setting changed";
e13bba36 7593 rekey_mandatory = TRUE;
7594 }
7595
7596 if (ssh->cfg.ssh2_des_cbc != cfg->ssh2_des_cbc ||
7597 memcmp(ssh->cfg.ssh_cipherlist, cfg->ssh_cipherlist,
7598 sizeof(ssh->cfg.ssh_cipherlist))) {
f382c87d 7599 rekeying = "cipher settings changed";
e13bba36 7600 rekey_mandatory = TRUE;
e6c1536e 7601 }
7602
86916870 7603 ssh->cfg = *cfg; /* STRUCTURE COPY */
e13bba36 7604
7605 if (rekeying) {
7606 if (!ssh->kex_in_progress) {
7607 do_ssh2_transport(ssh, rekeying, -1, NULL);
7608 } else if (rekey_mandatory) {
7609 ssh->deferred_rekey_reason = rekeying;
7610 }
7611 }
86916870 7612}
7613
7614/*
374330e2 7615 * Called to send data down the Telnet connection.
7616 */
51470298 7617static int ssh_send(void *handle, char *buf, int len)
32874aea 7618{
51470298 7619 Ssh ssh = (Ssh) handle;
7620
7621 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
5471d09a 7622 return 0;
374330e2 7623
d8baa528 7624 ssh->protocol(ssh, (unsigned char *)buf, len, 0);
5471d09a 7625
51470298 7626 return ssh_sendbuffer(ssh);
5471d09a 7627}
7628
7629/*
7630 * Called to query the current amount of buffered stdin data.
7631 */
51470298 7632static int ssh_sendbuffer(void *handle)
5471d09a 7633{
51470298 7634 Ssh ssh = (Ssh) handle;
5471d09a 7635 int override_value;
7636
51470298 7637 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
5471d09a 7638 return 0;
7639
7640 /*
7641 * If the SSH socket itself has backed up, add the total backup
7642 * size on that to any individual buffer on the stdin channel.
7643 */
7644 override_value = 0;
51470298 7645 if (ssh->throttled_all)
7646 override_value = ssh->overall_bufsize;
5471d09a 7647
51470298 7648 if (ssh->version == 1) {
5471d09a 7649 return override_value;
51470298 7650 } else if (ssh->version == 2) {
7651 if (!ssh->mainchan || ssh->mainchan->closes > 0)
5471d09a 7652 return override_value;
7653 else
51470298 7654 return (override_value +
7655 bufchain_size(&ssh->mainchan->v.v2.outbuffer));
5471d09a 7656 }
7657
7658 return 0;
374330e2 7659}
7660
7661/*
6e48c3fe 7662 * Called to set the size of the window from SSH's POV.
374330e2 7663 */
51470298 7664static void ssh_size(void *handle, int width, int height)
32874aea 7665{
51470298 7666 Ssh ssh = (Ssh) handle;
ff3187f6 7667 struct Packet *pktout;
51470298 7668
7669 ssh->term_width = width;
7670 ssh->term_height = height;
f278d6f8 7671
51470298 7672 switch (ssh->state) {
374330e2 7673 case SSH_STATE_BEFORE_SIZE:
3687d221 7674 case SSH_STATE_PREPACKET:
21248260 7675 case SSH_STATE_CLOSED:
374330e2 7676 break; /* do nothing */
7677 case SSH_STATE_INTERMED:
51470298 7678 ssh->size_needed = TRUE; /* buffer for later */
374330e2 7679 break;
7680 case SSH_STATE_SESSION:
86916870 7681 if (!ssh->cfg.nopty) {
51470298 7682 if (ssh->version == 1) {
7683 send_packet(ssh, SSH1_CMSG_WINDOW_SIZE,
7684 PKT_INT, ssh->term_height,
7685 PKT_INT, ssh->term_width,
32874aea 7686 PKT_INT, 0, PKT_INT, 0, PKT_END);
0ed48730 7687 } else if (ssh->mainchan) {
ff3187f6 7688 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7689 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7690 ssh2_pkt_addstring(pktout, "window-change");
7691 ssh2_pkt_addbool(pktout, 0);
7692 ssh2_pkt_adduint32(pktout, ssh->term_width);
7693 ssh2_pkt_adduint32(pktout, ssh->term_height);
7694 ssh2_pkt_adduint32(pktout, 0);
7695 ssh2_pkt_adduint32(pktout, 0);
7696 ssh2_pkt_send(ssh, pktout);
32874aea 7697 }
7698 }
7699 break;
374330e2 7700 }
7701}
7702
7703/*
125105d1 7704 * Return a list of the special codes that make sense in this
7705 * protocol.
7706 */
7707static const struct telnet_special *ssh_get_specials(void *handle)
7708{
786ba75e 7709 static const struct telnet_special ssh1_ignore_special[] = {
7710 {"IGNORE message", TS_NOP}
7711 };
7712 static const struct telnet_special ssh2_transport_specials[] = {
62638676 7713 {"IGNORE message", TS_NOP},
9442dd57 7714 {"Repeat key exchange", TS_REKEY},
62638676 7715 };
7716 static const struct telnet_special ssh2_session_specials[] = {
6f2d0cde 7717 {NULL, TS_SEP},
7718 {"Break", TS_BRK},
786ba75e 7719 /* These are the signal names defined by draft-ietf-secsh-connect-23.
6f2d0cde 7720 * They include all the ISO C signals, but are a subset of the POSIX
7721 * required signals. */
7722 {"SIGINT (Interrupt)", TS_SIGINT},
7723 {"SIGTERM (Terminate)", TS_SIGTERM},
7724 {"SIGKILL (Kill)", TS_SIGKILL},
7725 {"SIGQUIT (Quit)", TS_SIGQUIT},
7726 {"SIGHUP (Hangup)", TS_SIGHUP},
7727 {"More signals", TS_SUBMENU},
7728 {"SIGABRT", TS_SIGABRT}, {"SIGALRM", TS_SIGALRM},
7729 {"SIGFPE", TS_SIGFPE}, {"SIGILL", TS_SIGILL},
7730 {"SIGPIPE", TS_SIGPIPE}, {"SIGSEGV", TS_SIGSEGV},
7731 {"SIGUSR1", TS_SIGUSR1}, {"SIGUSR2", TS_SIGUSR2},
7732 {NULL, TS_EXITMENU}
62638676 7733 };
7734 static const struct telnet_special specials_end[] = {
6f2d0cde 7735 {NULL, TS_EXITMENU}
62638676 7736 };
786ba75e 7737 /* XXX review this length for any changes: */
7738 static struct telnet_special ssh_specials[lenof(ssh2_transport_specials) +
62638676 7739 lenof(ssh2_session_specials) +
7740 lenof(specials_end)];
125105d1 7741 Ssh ssh = (Ssh) handle;
62638676 7742 int i = 0;
7743#define ADD_SPECIALS(name) \
7744 do { \
7745 assert((i + lenof(name)) <= lenof(ssh_specials)); \
7746 memcpy(&ssh_specials[i], name, sizeof name); \
7747 i += lenof(name); \
7748 } while(0)
125105d1 7749
7750 if (ssh->version == 1) {
62638676 7751 /* Don't bother offering IGNORE if we've decided the remote
7752 * won't cope with it, since we wouldn't bother sending it if
7753 * asked anyway. */
7754 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE))
786ba75e 7755 ADD_SPECIALS(ssh1_ignore_special);
125105d1 7756 } else if (ssh->version == 2) {
786ba75e 7757 ADD_SPECIALS(ssh2_transport_specials);
62638676 7758 if (ssh->mainchan)
7759 ADD_SPECIALS(ssh2_session_specials);
7760 } /* else we're not ready yet */
7761
7762 if (i) {
7763 ADD_SPECIALS(specials_end);
7764 return ssh_specials;
7765 } else {
125105d1 7766 return NULL;
62638676 7767 }
7768#undef ADD_SPECIALS
125105d1 7769}
7770
7771/*
6abbf9e3 7772 * Send Telnet special codes. TS_EOF is useful for `plink', so you
7773 * can send an EOF and collect resulting output (e.g. `plink
7774 * hostname sort').
374330e2 7775 */
51470298 7776static void ssh_special(void *handle, Telnet_Special code)
32874aea 7777{
51470298 7778 Ssh ssh = (Ssh) handle;
ff3187f6 7779 struct Packet *pktout;
51470298 7780
6abbf9e3 7781 if (code == TS_EOF) {
51470298 7782 if (ssh->state != SSH_STATE_SESSION) {
32874aea 7783 /*
7784 * Buffer the EOF in case we are pre-SESSION, so we can
7785 * send it as soon as we reach SESSION.
7786 */
7787 if (code == TS_EOF)
51470298 7788 ssh->eof_needed = TRUE;
32874aea 7789 return;
7790 }
51470298 7791 if (ssh->version == 1) {
7792 send_packet(ssh, SSH1_CMSG_EOF, PKT_END);
0ed48730 7793 } else if (ssh->mainchan) {
ff3187f6 7794 struct Packet *pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF);
7795 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7796 ssh2_pkt_send(ssh, pktout);
32874aea 7797 }
7798 logevent("Sent EOF message");
125105d1 7799 } else if (code == TS_PING || code == TS_NOP) {
51470298 7800 if (ssh->state == SSH_STATE_CLOSED
7801 || ssh->state == SSH_STATE_PREPACKET) return;
7802 if (ssh->version == 1) {
7803 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE))
7804 send_packet(ssh, SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
32874aea 7805 } else {
ff3187f6 7806 pktout = ssh2_pkt_init(SSH2_MSG_IGNORE);
7807 ssh2_pkt_addstring_start(pktout);
590f6a5f 7808 ssh2_pkt_send_noqueue(ssh, pktout);
32874aea 7809 }
9442dd57 7810 } else if (code == TS_REKEY) {
7811 if (!ssh->kex_in_progress && ssh->version == 2) {
f382c87d 7812 do_ssh2_transport(ssh, "at user request", -1, NULL);
9442dd57 7813 }
125105d1 7814 } else if (code == TS_BRK) {
7815 if (ssh->state == SSH_STATE_CLOSED
7816 || ssh->state == SSH_STATE_PREPACKET) return;
7817 if (ssh->version == 1) {
7818 logevent("Unable to send BREAK signal in SSH1");
0ed48730 7819 } else if (ssh->mainchan) {
ff3187f6 7820 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7821 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7822 ssh2_pkt_addstring(pktout, "break");
7823 ssh2_pkt_addbool(pktout, 0);
7824 ssh2_pkt_adduint32(pktout, 0); /* default break length */
7825 ssh2_pkt_send(ssh, pktout);
125105d1 7826 }
6abbf9e3 7827 } else {
6f2d0cde 7828 /* Is is a POSIX signal? */
7829 char *signame = NULL;
7830 if (code == TS_SIGABRT) signame = "ABRT";
7831 if (code == TS_SIGALRM) signame = "ALRM";
7832 if (code == TS_SIGFPE) signame = "FPE";
7833 if (code == TS_SIGHUP) signame = "HUP";
7834 if (code == TS_SIGILL) signame = "ILL";
7835 if (code == TS_SIGINT) signame = "INT";
7836 if (code == TS_SIGKILL) signame = "KILL";
7837 if (code == TS_SIGPIPE) signame = "PIPE";
7838 if (code == TS_SIGQUIT) signame = "QUIT";
7839 if (code == TS_SIGSEGV) signame = "SEGV";
7840 if (code == TS_SIGTERM) signame = "TERM";
7841 if (code == TS_SIGUSR1) signame = "USR1";
7842 if (code == TS_SIGUSR2) signame = "USR2";
7843 /* The SSH-2 protocol does in principle support arbitrary named
7844 * signals, including signame@domain, but we don't support those. */
7845 if (signame) {
7846 /* It's a signal. */
7847 if (ssh->version == 2 && ssh->mainchan) {
ff3187f6 7848 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7849 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7850 ssh2_pkt_addstring(pktout, "signal");
7851 ssh2_pkt_addbool(pktout, 0);
7852 ssh2_pkt_addstring(pktout, signame);
7853 ssh2_pkt_send(ssh, pktout);
6f2d0cde 7854 logeventf(ssh, "Sent signal SIG%s", signame);
7855 }
7856 } else {
7857 /* Never heard of it. Do nothing */
7858 }
6abbf9e3 7859 }
374330e2 7860}
7861
51470298 7862void *new_sock_channel(void *handle, Socket s)
d74d141c 7863{
51470298 7864 Ssh ssh = (Ssh) handle;
d74d141c 7865 struct ssh_channel *c;
3d88e64d 7866 c = snew(struct ssh_channel);
51470298 7867 c->ssh = ssh;
d74d141c 7868
7869 if (c) {
bc240b21 7870 c->remoteid = -1; /* to be set when open confirmed */
51470298 7871 c->localid = alloc_channel_id(ssh);
d74d141c 7872 c->closes = 0;
bc240b21 7873 c->type = CHAN_SOCKDATA_DORMANT;/* identify channel type */
d74d141c 7874 c->u.pfd.s = s;
013dd8c0 7875 bufchain_init(&c->v.v2.outbuffer);
51470298 7876 add234(ssh->channels, c);
d74d141c 7877 }
7878 return c;
7879}
7880
5471d09a 7881/*
7882 * This is called when stdout/stderr (the entity to which
7883 * from_backend sends data) manages to clear some backlog.
7884 */
ae9ae89f 7885static void ssh_unthrottle(void *handle, int bufsize)
5471d09a 7886{
51470298 7887 Ssh ssh = (Ssh) handle;
7888 if (ssh->version == 1) {
7889 if (ssh->v1_stdout_throttling && bufsize < SSH1_BUFFER_LIMIT) {
7890 ssh->v1_stdout_throttling = 0;
7891 ssh1_throttle(ssh, -1);
5471d09a 7892 }
7893 } else {
51470298 7894 if (ssh->mainchan && ssh->mainchan->closes == 0)
7895 ssh2_set_window(ssh->mainchan, OUR_V2_WINSIZE - bufsize);
5471d09a 7896 }
7897}
7898
6b78788a 7899void ssh_send_port_open(void *channel, char *hostname, int port, char *org)
d74d141c 7900{
7901 struct ssh_channel *c = (struct ssh_channel *)channel;
6b78788a 7902 Ssh ssh = c->ssh;
ff3187f6 7903 struct Packet *pktout;
d74d141c 7904
57356d63 7905 logeventf(ssh, "Opening forwarded connection to %s:%d", hostname, port);
d74d141c 7906
51470298 7907 if (ssh->version == 1) {
7908 send_packet(ssh, SSH1_MSG_PORT_OPEN,
bc240b21 7909 PKT_INT, c->localid,
7910 PKT_STR, hostname,
7911 PKT_INT, port,
31fb1866 7912 /* PKT_STR, <org:orgport>, */
bc240b21 7913 PKT_END);
7914 } else {
ff3187f6 7915 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
7916 ssh2_pkt_addstring(pktout, "direct-tcpip");
7917 ssh2_pkt_adduint32(pktout, c->localid);
5471d09a 7918 c->v.v2.locwindow = OUR_V2_WINSIZE;
ff3187f6 7919 ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);/* our window size */
7920 ssh2_pkt_adduint32(pktout, 0x4000UL); /* our max pkt size */
7921 ssh2_pkt_addstring(pktout, hostname);
7922 ssh2_pkt_adduint32(pktout, port);
bc240b21 7923 /*
7924 * We make up values for the originator data; partly it's
7925 * too much hassle to keep track, and partly I'm not
7926 * convinced the server should be told details like that
7927 * about my local network configuration.
7928 */
ff3187f6 7929 ssh2_pkt_addstring(pktout, "client-side-connection");
7930 ssh2_pkt_adduint32(pktout, 0);
7931 ssh2_pkt_send(ssh, pktout);
bc240b21 7932 }
d74d141c 7933}
7934
51470298 7935static Socket ssh_socket(void *handle)
32874aea 7936{
51470298 7937 Ssh ssh = (Ssh) handle;
7938 return ssh->s;
32874aea 7939}
8ccc75b0 7940
51470298 7941static int ssh_sendok(void *handle)
32874aea 7942{
51470298 7943 Ssh ssh = (Ssh) handle;
7944 return ssh->send_ok;
32874aea 7945}
fb09bf1c 7946
51470298 7947static int ssh_ldisc(void *handle, int option)
32874aea 7948{
51470298 7949 Ssh ssh = (Ssh) handle;
32874aea 7950 if (option == LD_ECHO)
51470298 7951 return ssh->echoing;
32874aea 7952 if (option == LD_EDIT)
51470298 7953 return ssh->editing;
0965bee0 7954 return FALSE;
7955}
7956
b9d7bcad 7957static void ssh_provide_ldisc(void *handle, void *ldisc)
7958{
7959 Ssh ssh = (Ssh) handle;
7960 ssh->ldisc = ldisc;
7961}
7962
a8327734 7963static void ssh_provide_logctx(void *handle, void *logctx)
7964{
7965 Ssh ssh = (Ssh) handle;
7966 ssh->logctx = logctx;
7967}
7968
51470298 7969static int ssh_return_exitcode(void *handle)
7970{
7971 Ssh ssh = (Ssh) handle;
3bb2f322 7972 if (ssh->s != NULL)
7973 return -1;
7974 else
7975 return (ssh->exitcode >= 0 ? ssh->exitcode : 0);
51470298 7976}
7977
7978/*
f89c3294 7979 * cfg_info for SSH is the currently running version of the
7980 * protocol. (1 for 1; 2 for 2; 0 for not-decided-yet.)
7981 */
7982static int ssh_cfg_info(void *handle)
7983{
7984 Ssh ssh = (Ssh) handle;
7985 return ssh->version;
7986}
7987
7988/*
51470298 7989 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
7990 * that fails. This variable is the means by which scp.c can reach
7991 * into the SSH code and find out which one it got.
7992 */
7993extern int ssh_fallback_cmd(void *handle)
d8d6c7e5 7994{
51470298 7995 Ssh ssh = (Ssh) handle;
7996 return ssh->fallback_cmd;
d8d6c7e5 7997}
7998
374330e2 7999Backend ssh_backend = {
8000 ssh_init,
fabd1805 8001 ssh_free,
86916870 8002 ssh_reconfig,
374330e2 8003 ssh_send,
5471d09a 8004 ssh_sendbuffer,
374330e2 8005 ssh_size,
4017be6d 8006 ssh_special,
125105d1 8007 ssh_get_specials,
8ccc75b0 8008 ssh_socket,
d8d6c7e5 8009 ssh_return_exitcode,
97db3be4 8010 ssh_sendok,
0965bee0 8011 ssh_ldisc,
b9d7bcad 8012 ssh_provide_ldisc,
a8327734 8013 ssh_provide_logctx,
5471d09a 8014 ssh_unthrottle,
f89c3294 8015 ssh_cfg_info,
97db3be4 8016 22
bc240b21 8017};
Local modifications for Simon Tatham's `PuTTY' SSH client and terminal emulator