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Add puttytel binary to .cvsignore
[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 */
107#define SSH2_PKTCTX_DHGROUP1 0x0001
108#define SSH2_PKTCTX_DHGEX 0x0002
109#define SSH2_PKTCTX_PUBLICKEY 0x0010
110#define SSH2_PKTCTX_PASSWORD 0x0020
111#define SSH2_PKTCTX_KBDINTER 0x0040
112#define SSH2_PKTCTX_AUTH_MASK 0x00F0
113
32874aea 114#define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
115#define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
116#define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
117#define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
118#define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
119#define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
120#define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
121#define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
122#define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
123#define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
124#define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
125#define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */
126#define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */
127#define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */
128#define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */
38c4a8da 129
130static const char *const ssh2_disconnect_reasons[] = {
131 NULL,
132 "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
133 "SSH_DISCONNECT_PROTOCOL_ERROR",
134 "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
135 "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
136 "SSH_DISCONNECT_MAC_ERROR",
137 "SSH_DISCONNECT_COMPRESSION_ERROR",
138 "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
139 "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
140 "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
141 "SSH_DISCONNECT_CONNECTION_LOST",
142 "SSH_DISCONNECT_BY_APPLICATION",
143 "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
144 "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
145 "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
146 "SSH_DISCONNECT_ILLEGAL_USER_NAME",
147};
9005f3ba 148
32874aea 149#define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
150#define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
151#define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
152#define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
d211621f 153
32874aea 154#define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
fb09bf1c 155
7d503c31 156/*
157 * Various remote-bug flags.
158 */
159#define BUG_CHOKES_ON_SSH1_IGNORE 1
160#define BUG_SSH2_HMAC 2
bd358db1 161#define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
0df73905 162#define BUG_CHOKES_ON_RSA 8
1dd353b5 163#define BUG_SSH2_RSA_PADDING 16
088bde77 164#define BUG_SSH2_DERIVEKEY 32
8e975795 165#define BUG_SSH2_DH_GEX 64
dda87a28 166#define BUG_SSH2_PK_SESSIONID 128
bd358db1 167
00db133f 168#define translate(x) if (type == x) return #x
51470298 169#define translatec(x,ctx) if (type == x && (pkt_ctx & ctx)) return #x
ae9ae89f 170static char *ssh1_pkt_type(int type)
00db133f 171{
172 translate(SSH1_MSG_DISCONNECT);
173 translate(SSH1_SMSG_PUBLIC_KEY);
174 translate(SSH1_CMSG_SESSION_KEY);
175 translate(SSH1_CMSG_USER);
176 translate(SSH1_CMSG_AUTH_RSA);
177 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE);
178 translate(SSH1_CMSG_AUTH_RSA_RESPONSE);
179 translate(SSH1_CMSG_AUTH_PASSWORD);
180 translate(SSH1_CMSG_REQUEST_PTY);
181 translate(SSH1_CMSG_WINDOW_SIZE);
182 translate(SSH1_CMSG_EXEC_SHELL);
183 translate(SSH1_CMSG_EXEC_CMD);
184 translate(SSH1_SMSG_SUCCESS);
185 translate(SSH1_SMSG_FAILURE);
186 translate(SSH1_CMSG_STDIN_DATA);
187 translate(SSH1_SMSG_STDOUT_DATA);
188 translate(SSH1_SMSG_STDERR_DATA);
189 translate(SSH1_CMSG_EOF);
190 translate(SSH1_SMSG_EXIT_STATUS);
191 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION);
192 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE);
193 translate(SSH1_MSG_CHANNEL_DATA);
194 translate(SSH1_MSG_CHANNEL_CLOSE);
195 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION);
196 translate(SSH1_SMSG_X11_OPEN);
197 translate(SSH1_CMSG_PORT_FORWARD_REQUEST);
198 translate(SSH1_MSG_PORT_OPEN);
199 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING);
200 translate(SSH1_SMSG_AGENT_OPEN);
201 translate(SSH1_MSG_IGNORE);
202 translate(SSH1_CMSG_EXIT_CONFIRMATION);
203 translate(SSH1_CMSG_X11_REQUEST_FORWARDING);
204 translate(SSH1_CMSG_AUTH_RHOSTS_RSA);
205 translate(SSH1_MSG_DEBUG);
206 translate(SSH1_CMSG_REQUEST_COMPRESSION);
207 translate(SSH1_CMSG_AUTH_TIS);
208 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE);
209 translate(SSH1_CMSG_AUTH_TIS_RESPONSE);
210 translate(SSH1_CMSG_AUTH_CCARD);
211 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE);
212 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE);
213 return "unknown";
214}
ae9ae89f 215static char *ssh2_pkt_type(int pkt_ctx, int type)
00db133f 216{
217 translate(SSH2_MSG_DISCONNECT);
218 translate(SSH2_MSG_IGNORE);
219 translate(SSH2_MSG_UNIMPLEMENTED);
220 translate(SSH2_MSG_DEBUG);
221 translate(SSH2_MSG_SERVICE_REQUEST);
222 translate(SSH2_MSG_SERVICE_ACCEPT);
223 translate(SSH2_MSG_KEXINIT);
224 translate(SSH2_MSG_NEWKEYS);
225 translatec(SSH2_MSG_KEXDH_INIT, SSH2_PKTCTX_DHGROUP1);
226 translatec(SSH2_MSG_KEXDH_REPLY, SSH2_PKTCTX_DHGROUP1);
227 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST, SSH2_PKTCTX_DHGEX);
228 translatec(SSH2_MSG_KEX_DH_GEX_GROUP, SSH2_PKTCTX_DHGEX);
229 translatec(SSH2_MSG_KEX_DH_GEX_INIT, SSH2_PKTCTX_DHGEX);
230 translatec(SSH2_MSG_KEX_DH_GEX_REPLY, SSH2_PKTCTX_DHGEX);
231 translate(SSH2_MSG_USERAUTH_REQUEST);
232 translate(SSH2_MSG_USERAUTH_FAILURE);
233 translate(SSH2_MSG_USERAUTH_SUCCESS);
234 translate(SSH2_MSG_USERAUTH_BANNER);
235 translatec(SSH2_MSG_USERAUTH_PK_OK, SSH2_PKTCTX_PUBLICKEY);
236 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, SSH2_PKTCTX_PASSWORD);
237 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST, SSH2_PKTCTX_KBDINTER);
238 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE, SSH2_PKTCTX_KBDINTER);
239 translate(SSH2_MSG_GLOBAL_REQUEST);
240 translate(SSH2_MSG_REQUEST_SUCCESS);
241 translate(SSH2_MSG_REQUEST_FAILURE);
242 translate(SSH2_MSG_CHANNEL_OPEN);
243 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
244 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE);
245 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
246 translate(SSH2_MSG_CHANNEL_DATA);
247 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA);
248 translate(SSH2_MSG_CHANNEL_EOF);
249 translate(SSH2_MSG_CHANNEL_CLOSE);
250 translate(SSH2_MSG_CHANNEL_REQUEST);
251 translate(SSH2_MSG_CHANNEL_SUCCESS);
252 translate(SSH2_MSG_CHANNEL_FAILURE);
253 return "unknown";
254}
255#undef translate
256#undef translatec
7d503c31 257
fb09bf1c 258#define GET_32BIT(cp) \
259 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
260 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
261 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
262 ((unsigned long)(unsigned char)(cp)[3]))
263
264#define PUT_32BIT(cp, value) { \
265 (cp)[0] = (unsigned char)((value) >> 24); \
266 (cp)[1] = (unsigned char)((value) >> 16); \
267 (cp)[2] = (unsigned char)((value) >> 8); \
268 (cp)[3] = (unsigned char)(value); }
269
7cca0d81 270enum { PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR, PKT_BIGNUM };
972a41c8 271
acddebd9 272/*
273 * Coroutine mechanics for the sillier bits of the code. If these
274 * macros look impenetrable to you, you might find it helpful to
275 * read
276 *
277 * http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
278 *
279 * which explains the theory behind these macros.
b624d1e6 280 *
281 * In particular, if you are getting `case expression not constant'
282 * errors when building with MS Visual Studio, this is because MS's
283 * Edit and Continue debugging feature causes their compiler to
284 * violate ANSI C. To disable Edit and Continue debugging:
285 *
286 * - right-click ssh.c in the FileView
287 * - click Settings
288 * - select the C/C++ tab and the General category
289 * - under `Debug info:', select anything _other_ than `Program
290 * Database for Edit and Continue'.
acddebd9 291 */
51470298 292#define crBegin(v) { int *crLine = &v; switch(v) { case 0:;
293#define crState(t) \
294 struct t *s; \
3d88e64d 295 if (!ssh->t) ssh->t = snew(struct t); \
51470298 296 s = ssh->t;
297#define crFinish(z) } *crLine = 0; return (z); }
298#define crFinishV } *crLine = 0; return; }
374330e2 299#define crReturn(z) \
300 do {\
51470298 301 *crLine =__LINE__; return (z); case __LINE__:;\
374330e2 302 } while (0)
303#define crReturnV \
304 do {\
51470298 305 *crLine=__LINE__; return; case __LINE__:;\
374330e2 306 } while (0)
51470298 307#define crStop(z) do{ *crLine = 0; return (z); }while(0)
308#define crStopV do{ *crLine = 0; return; }while(0)
fb09bf1c 309#define crWaitUntil(c) do { crReturn(0); } while (!(c))
7cca0d81 310#define crWaitUntilV(c) do { crReturnV; } while (!(c))
374330e2 311
51470298 312typedef struct ssh_tag *Ssh;
313
51470298 314static void ssh2_pkt_init(Ssh, int pkt_type);
315static void ssh2_pkt_addbool(Ssh, unsigned char value);
316static void ssh2_pkt_adduint32(Ssh, unsigned long value);
317static void ssh2_pkt_addstring_start(Ssh);
318static void ssh2_pkt_addstring_str(Ssh, char *data);
319static void ssh2_pkt_addstring_data(Ssh, char *data, int len);
320static void ssh2_pkt_addstring(Ssh, char *data);
d8baa528 321static unsigned char *ssh2_mpint_fmt(Bignum b, int *len);
51470298 322static void ssh2_pkt_addmp(Ssh, Bignum b);
323static int ssh2_pkt_construct(Ssh);
324static void ssh2_pkt_send(Ssh);
3d63ca2e 325
5471d09a 326/*
327 * Buffer management constants. There are several of these for
328 * various different purposes:
329 *
330 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
331 * on a local data stream before we throttle the whole SSH
332 * connection (in SSH1 only). Throttling the whole connection is
333 * pretty drastic so we set this high in the hope it won't
334 * happen very often.
335 *
336 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
337 * on the SSH connection itself before we defensively throttle
338 * _all_ local data streams. This is pretty drastic too (though
339 * thankfully unlikely in SSH2 since the window mechanism should
340 * ensure that the server never has any need to throttle its end
341 * of the connection), so we set this high as well.
342 *
343 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
344 * channels.
345 */
346
347#define SSH1_BUFFER_LIMIT 32768
348#define SSH_MAX_BACKLOG 32768
349#define OUR_V2_WINSIZE 16384
d74d141c 350
a92dd380 351const static struct ssh_kex *kex_algs[] = {
a92dd380 352 &ssh_diffiehellman_gex,
32874aea 353 &ssh_diffiehellman
354};
e5574168 355
85cc02bb 356const static struct ssh_signkey *hostkey_algs[] = { &ssh_rsa, &ssh_dss };
e5574168 357
e0e1a00d 358static void *nullmac_make_context(void)
359{
360 return NULL;
361}
362static void nullmac_free_context(void *handle)
363{
364}
365static void nullmac_key(void *handle, unsigned char *key)
32874aea 366{
367}
e0e1a00d 368static void nullmac_generate(void *handle, unsigned char *blk, int len,
32874aea 369 unsigned long seq)
370{
371}
e0e1a00d 372static int nullmac_verify(void *handle, unsigned char *blk, int len,
373 unsigned long seq)
32874aea 374{
375 return 1;
376}
57476f6b 377const static struct ssh_mac ssh_mac_none = {
e0e1a00d 378 nullmac_make_context, nullmac_free_context, nullmac_key,
379 nullmac_generate, nullmac_verify, "none", 0
e5574168 380};
8b2715b2 381const static struct ssh_mac *macs[] = {
32874aea 382 &ssh_sha1, &ssh_md5, &ssh_mac_none
383};
8b2715b2 384const static struct ssh_mac *buggymacs[] = {
32874aea 385 &ssh_sha1_buggy, &ssh_md5, &ssh_mac_none
386};
e5574168 387
5366aed8 388static void *ssh_comp_none_init(void)
389{
390 return NULL;
391}
392static void ssh_comp_none_cleanup(void *handle)
32874aea 393{
394}
5366aed8 395static int ssh_comp_none_block(void *handle, unsigned char *block, int len,
32874aea 396 unsigned char **outblock, int *outlen)
397{
398 return 0;
399}
5366aed8 400static int ssh_comp_none_disable(void *handle)
32874aea 401{
4ba9b64b 402 return 0;
403}
57476f6b 404const static struct ssh_compress ssh_comp_none = {
4ba9b64b 405 "none",
5366aed8 406 ssh_comp_none_init, ssh_comp_none_cleanup, ssh_comp_none_block,
407 ssh_comp_none_init, ssh_comp_none_cleanup, ssh_comp_none_block,
408 ssh_comp_none_disable, NULL
e5574168 409};
4ba9b64b 410extern const struct ssh_compress ssh_zlib;
411const static struct ssh_compress *compressions[] = {
32874aea 412 &ssh_zlib, &ssh_comp_none
413};
374330e2 414
32874aea 415enum { /* channel types */
783415f8 416 CHAN_MAINSESSION,
417 CHAN_X11,
418 CHAN_AGENT,
bc240b21 419 CHAN_SOCKDATA,
420 CHAN_SOCKDATA_DORMANT /* one the remote hasn't confirmed */
783415f8 421};
422
dacbd0e8 423/*
424 * 2-3-4 tree storing channels.
425 */
426struct ssh_channel {
51470298 427 Ssh ssh; /* pointer back to main context */
d211621f 428 unsigned remoteid, localid;
dacbd0e8 429 int type;
0357890f 430 /*
431 * In SSH1, this value contains four bits:
432 *
433 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
434 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
435 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
436 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
437 *
438 * A channel is completely finished with when all four bits are set.
439 */
dacbd0e8 440 int closes;
5471d09a 441 union {
442 struct ssh1_data_channel {
443 int throttling;
444 } v1;
445 struct ssh2_data_channel {
446 bufchain outbuffer;
447 unsigned remwindow, remmaxpkt;
448 unsigned locwindow;
449 } v2;
450 } v;
dacbd0e8 451 union {
32874aea 452 struct ssh_agent_channel {
453 unsigned char *message;
454 unsigned char msglen[4];
455 int lensofar, totallen;
456 } a;
457 struct ssh_x11_channel {
458 Socket s;
459 } x11;
d74d141c 460 struct ssh_pfd_channel {
461 Socket s;
462 } pfd;
dacbd0e8 463 } u;
464};
57476f6b 465
d74d141c 466/*
bc240b21 467 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
468 * 2 use this structure in different ways, reflecting SSH 2's
469 * altogether saner approach to port forwarding.
470 *
471 * In SSH 1, you arrange a remote forwarding by sending the server
472 * the remote port number, and the local destination host:port.
473 * When a connection comes in, the server sends you back that
474 * host:port pair, and you connect to it. This is a ready-made
475 * security hole if you're not on the ball: a malicious server
476 * could send you back _any_ host:port pair, so if you trustingly
477 * connect to the address it gives you then you've just opened the
478 * entire inside of your corporate network just by connecting
479 * through it to a dodgy SSH server. Hence, we must store a list of
480 * host:port pairs we _are_ trying to forward to, and reject a
481 * connection request from the server if it's not in the list.
482 *
483 * In SSH 2, each side of the connection minds its own business and
484 * doesn't send unnecessary information to the other. You arrange a
485 * remote forwarding by sending the server just the remote port
486 * number. When a connection comes in, the server tells you which
487 * of its ports was connected to; and _you_ have to remember what
488 * local host:port pair went with that port number.
489 *
490 * Hence: in SSH 1 this structure stores host:port pairs we intend
491 * to allow connections to, and is indexed by those host:port
492 * pairs. In SSH 2 it stores a mapping from source port to
493 * destination host:port pair, and is indexed by source port.
d74d141c 494 */
495struct ssh_rportfwd {
bc240b21 496 unsigned sport, dport;
497 char dhost[256];
d74d141c 498};
499
57476f6b 500struct Packet {
501 long length;
502 int type;
503 unsigned char *data;
504 unsigned char *body;
505 long savedpos;
506 long maxlen;
507};
508
51470298 509static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt);
510static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt);
511static void ssh_size(void *handle, int width, int height);
512static void ssh_special(void *handle, Telnet_Special);
5471d09a 513static int ssh2_try_send(struct ssh_channel *c);
51470298 514static void ssh2_add_channel_data(struct ssh_channel *c, char *buf, int len);
515static void ssh_throttle_all(Ssh ssh, int enable, int bufsize);
5471d09a 516static void ssh2_set_window(struct ssh_channel *c, unsigned newwin);
51470298 517static int ssh_sendbuffer(void *handle);
36f94d1f 518static void ssh_do_close(Ssh ssh);
57476f6b 519
51470298 520struct rdpkt1_state_tag {
57476f6b 521 long len, pad, biglen, to_read;
522 unsigned long realcrc, gotcrc;
523 unsigned char *p;
524 int i;
525 int chunk;
51470298 526};
57476f6b 527
51470298 528struct rdpkt2_state_tag {
960e736a 529 long len, pad, payload, packetlen, maclen;
530 int i;
531 int cipherblk;
532 unsigned long incoming_sequence;
51470298 533};
534
535struct ssh_tag {
536 const struct plug_function_table *fn;
537 /* the above field _must_ be first in the structure */
538
539 SHA_State exhash, exhashbase;
540
541 Socket s;
542
b9d7bcad 543 void *ldisc;
a8327734 544 void *logctx;
b9d7bcad 545
51470298 546 unsigned char session_key[32];
547 int v1_compressing;
548 int v1_remote_protoflags;
549 int v1_local_protoflags;
550 int agentfwd_enabled;
551 int X11_fwd_enabled;
552 int remote_bugs;
553 const struct ssh_cipher *cipher;
371e569c 554 void *v1_cipher_ctx;
0183b242 555 void *crcda_ctx;
51470298 556 const struct ssh2_cipher *cscipher, *sccipher;
371e569c 557 void *cs_cipher_ctx, *sc_cipher_ctx;
51470298 558 const struct ssh_mac *csmac, *scmac;
e0e1a00d 559 void *cs_mac_ctx, *sc_mac_ctx;
51470298 560 const struct ssh_compress *cscomp, *sccomp;
5366aed8 561 void *cs_comp_ctx, *sc_comp_ctx;
51470298 562 const struct ssh_kex *kex;
563 const struct ssh_signkey *hostkey;
564 unsigned char v2_session_id[20];
27cd7fc2 565 void *kex_ctx;
51470298 566
567 char *savedhost;
568 int savedport;
569 int send_ok;
570 int echoing, editing;
571
572 void *frontend;
573
574 int term_width, term_height;
575
576 tree234 *channels; /* indexed by local id */
577 struct ssh_channel *mainchan; /* primary session channel */
578 int exitcode;
579
580 tree234 *rportfwds;
581
582 enum {
583 SSH_STATE_PREPACKET,
584 SSH_STATE_BEFORE_SIZE,
585 SSH_STATE_INTERMED,
586 SSH_STATE_SESSION,
587 SSH_STATE_CLOSED
588 } state;
589
590 int size_needed, eof_needed;
591
592 struct Packet pktin;
593 struct Packet pktout;
594 unsigned char *deferred_send_data;
595 int deferred_len, deferred_size;
596
597 /*
598 * Gross hack: pscp will try to start SFTP but fall back to
599 * scp1 if that fails. This variable is the means by which
600 * scp.c can reach into the SSH code and find out which one it
601 * got.
602 */
603 int fallback_cmd;
604
605 /*
606 * Used for username and password input.
607 */
608 char *userpass_input_buffer;
609 int userpass_input_buflen;
610 int userpass_input_bufpos;
611 int userpass_input_echo;
612
613 char *portfwd_strptr;
614 int pkt_ctx;
615
302121de 616 void *x11auth;
617
51470298 618 int version;
619 int v1_throttle_count;
620 int overall_bufsize;
621 int throttled_all;
622 int v1_stdout_throttling;
623 int v2_outgoing_sequence;
624
625 int ssh1_rdpkt_crstate;
626 int ssh2_rdpkt_crstate;
627 int do_ssh_init_crstate;
628 int ssh_gotdata_crstate;
629 int ssh1_protocol_crstate;
630 int do_ssh1_login_crstate;
631 int do_ssh2_transport_crstate;
632 int do_ssh2_authconn_crstate;
633
634 void *do_ssh_init_state;
635 void *do_ssh1_login_state;
636 void *do_ssh2_transport_state;
637 void *do_ssh2_authconn_state;
638
639 struct rdpkt1_state_tag rdpkt1_state;
640 struct rdpkt2_state_tag rdpkt2_state;
641
642 void (*protocol) (Ssh ssh, unsigned char *in, int inlen, int ispkt);
643 int (*s_rdpkt) (Ssh ssh, unsigned char **data, int *datalen);
86916870 644
645 /*
646 * We maintain a full _copy_ of a Config structure here, not
647 * merely a pointer to it. That way, when we're passed a new
648 * one for reconfiguration, we can check the differences and
649 * potentially reconfigure port forwardings etc in mid-session.
650 */
651 Config cfg;
51470298 652};
960e736a 653
382908ad 654#define logevent(s) logevent(ssh->frontend, s)
a8327734 655
656/* logevent, only printf-formatted. */
ae9ae89f 657static void logeventf(Ssh ssh, char *fmt, ...)
a8327734 658{
659 va_list ap;
57356d63 660 char *buf;
a8327734 661
662 va_start(ap, fmt);
57356d63 663 buf = dupvprintf(fmt, ap);
a8327734 664 va_end(ap);
57356d63 665 logevent(buf);
57356d63 666 sfree(buf);
a8327734 667}
668
6b5cf8b4 669#define bombout(msg) \
670 do { \
671 char *text = dupprintf msg; \
36f94d1f 672 ssh_do_close(ssh); \
6b5cf8b4 673 logevent(text); \
674 connection_fatal(ssh->frontend, "%s", text); \
675 sfree(text); \
676 } while (0)
a8327734 677
32874aea 678static int ssh_channelcmp(void *av, void *bv)
679{
680 struct ssh_channel *a = (struct ssh_channel *) av;
681 struct ssh_channel *b = (struct ssh_channel *) bv;
682 if (a->localid < b->localid)
683 return -1;
684 if (a->localid > b->localid)
685 return +1;
dacbd0e8 686 return 0;
687}
32874aea 688static int ssh_channelfind(void *av, void *bv)
689{
690 unsigned *a = (unsigned *) av;
691 struct ssh_channel *b = (struct ssh_channel *) bv;
692 if (*a < b->localid)
693 return -1;
694 if (*a > b->localid)
695 return +1;
dacbd0e8 696 return 0;
697}
698
bc240b21 699static int ssh_rportcmp_ssh1(void *av, void *bv)
d74d141c 700{
701 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
702 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
703 int i;
bc240b21 704 if ( (i = strcmp(a->dhost, b->dhost)) != 0)
d74d141c 705 return i < 0 ? -1 : +1;
bc240b21 706 if (a->dport > b->dport)
707 return +1;
708 if (a->dport < b->dport)
709 return -1;
710 return 0;
711}
712
713static int ssh_rportcmp_ssh2(void *av, void *bv)
714{
715 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
716 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
cdcbdf3b 717
bc240b21 718 if (a->sport > b->sport)
d74d141c 719 return +1;
bc240b21 720 if (a->sport < b->sport)
721 return -1;
d74d141c 722 return 0;
723}
724
51470298 725static int alloc_channel_id(Ssh ssh)
32874aea 726{
260f3dec 727 const unsigned CHANNEL_NUMBER_OFFSET = 256;
728 unsigned low, high, mid;
d2371c81 729 int tsize;
730 struct ssh_channel *c;
731
732 /*
733 * First-fit allocation of channel numbers: always pick the
734 * lowest unused one. To do this, binary-search using the
735 * counted B-tree to find the largest channel ID which is in a
736 * contiguous sequence from the beginning. (Precisely
737 * everything in that sequence must have ID equal to its tree
738 * index plus CHANNEL_NUMBER_OFFSET.)
739 */
51470298 740 tsize = count234(ssh->channels);
d2371c81 741
32874aea 742 low = -1;
743 high = tsize;
d2371c81 744 while (high - low > 1) {
745 mid = (high + low) / 2;
51470298 746 c = index234(ssh->channels, mid);
d2371c81 747 if (c->localid == mid + CHANNEL_NUMBER_OFFSET)
748 low = mid; /* this one is fine */
749 else
750 high = mid; /* this one is past it */
751 }
752 /*
753 * Now low points to either -1, or the tree index of the
754 * largest ID in the initial sequence.
755 */
756 {
757 unsigned i = low + 1 + CHANNEL_NUMBER_OFFSET;
51470298 758 assert(NULL == find234(ssh->channels, &i, ssh_channelfind));
d2371c81 759 }
760 return low + 1 + CHANNEL_NUMBER_OFFSET;
761}
762
9fab77dc 763static void c_write(Ssh ssh, const char *buf, int len)
32874aea 764{
67779be7 765 if ((flags & FLAG_STDERR)) {
32874aea 766 int i;
767 for (i = 0; i < len; i++)
768 if (buf[i] != '\r')
769 fputc(buf[i], stderr);
fb09bf1c 770 return;
771 }
51470298 772 from_backend(ssh->frontend, 1, buf, len);
3bdaf79d 773}
774
9fab77dc 775static void c_write_untrusted(Ssh ssh, const char *buf, int len)
32874aea 776{
a209e957 777 int i;
778 for (i = 0; i < len; i++) {
32874aea 779 if (buf[i] == '\n')
51470298 780 c_write(ssh, "\r\n", 2);
32874aea 781 else if ((buf[i] & 0x60) || (buf[i] == '\r'))
51470298 782 c_write(ssh, buf + i, 1);
a209e957 783 }
784}
785
9fab77dc 786static void c_write_str(Ssh ssh, const char *buf)
32874aea 787{
51470298 788 c_write(ssh, buf, strlen(buf));
1408a877 789}
790
fb09bf1c 791/*
792 * Collect incoming data in the incoming packet buffer.
e5574168 793 * Decipher and verify the packet when it is completely read.
794 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
fb09bf1c 795 * Update the *data and *datalen variables.
796 * Return the additional nr of bytes needed, or 0 when
797 * a complete packet is available.
798 */
51470298 799static int ssh1_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
fb09bf1c 800{
51470298 801 struct rdpkt1_state_tag *st = &ssh->rdpkt1_state;
374330e2 802
51470298 803 crBegin(ssh->ssh1_rdpkt_crstate);
374330e2 804
32874aea 805 next_packet:
37508af4 806
51470298 807 ssh->pktin.type = 0;
808 ssh->pktin.length = 0;
374330e2 809
57476f6b 810 for (st->i = st->len = 0; st->i < 4; st->i++) {
fb09bf1c 811 while ((*datalen) == 0)
32874aea 812 crReturn(4 - st->i);
57476f6b 813 st->len = (st->len << 8) + **data;
fb09bf1c 814 (*data)++, (*datalen)--;
815 }
374330e2 816
57476f6b 817 st->pad = 8 - (st->len % 8);
818 st->biglen = st->len + st->pad;
51470298 819 ssh->pktin.length = st->len - 5;
fb09bf1c 820
51470298 821 if (ssh->pktin.maxlen < st->biglen) {
822 ssh->pktin.maxlen = st->biglen;
3d88e64d 823 ssh->pktin.data = sresize(ssh->pktin.data, st->biglen + APIEXTRA,
824 unsigned char);
fb09bf1c 825 }
374330e2 826
57476f6b 827 st->to_read = st->biglen;
51470298 828 st->p = ssh->pktin.data;
57476f6b 829 while (st->to_read > 0) {
32874aea 830 st->chunk = st->to_read;
fb09bf1c 831 while ((*datalen) == 0)
57476f6b 832 crReturn(st->to_read);
833 if (st->chunk > (*datalen))
834 st->chunk = (*datalen);
835 memcpy(st->p, *data, st->chunk);
836 *data += st->chunk;
837 *datalen -= st->chunk;
838 st->p += st->chunk;
839 st->to_read -= st->chunk;
fb09bf1c 840 }
374330e2 841
0183b242 842 if (ssh->cipher && detect_attack(ssh->crcda_ctx, ssh->pktin.data,
843 st->biglen, NULL)) {
6b5cf8b4 844 bombout(("Network attack (CRC compensation) detected!"));
7ffdbc1a 845 crStop(0);
9a3a93a5 846 }
847
51470298 848 if (ssh->cipher)
371e569c 849 ssh->cipher->decrypt(ssh->v1_cipher_ctx, ssh->pktin.data, st->biglen);
374330e2 850
51470298 851 st->realcrc = crc32(ssh->pktin.data, st->biglen - 4);
852 st->gotcrc = GET_32BIT(ssh->pktin.data + st->biglen - 4);
57476f6b 853 if (st->gotcrc != st->realcrc) {
6b5cf8b4 854 bombout(("Incorrect CRC received on packet"));
7ffdbc1a 855 crStop(0);
fb09bf1c 856 }
572f871e 857
51470298 858 ssh->pktin.body = ssh->pktin.data + st->pad + 1;
4ba9b64b 859
51470298 860 if (ssh->v1_compressing) {
4ba9b64b 861 unsigned char *decompblk;
862 int decomplen;
5366aed8 863 zlib_decompress_block(ssh->sc_comp_ctx,
864 ssh->pktin.body - 1, ssh->pktin.length + 1,
4ba9b64b 865 &decompblk, &decomplen);
866
51470298 867 if (ssh->pktin.maxlen < st->pad + decomplen) {
868 ssh->pktin.maxlen = st->pad + decomplen;
3d88e64d 869 ssh->pktin.data = sresize(ssh->pktin.data,
870 ssh->pktin.maxlen + APIEXTRA,
871 unsigned char);
51470298 872 ssh->pktin.body = ssh->pktin.data + st->pad + 1;
4ba9b64b 873 }
874
51470298 875 memcpy(ssh->pktin.body - 1, decompblk, decomplen);
dcbde236 876 sfree(decompblk);
51470298 877 ssh->pktin.length = decomplen - 1;
4ba9b64b 878 }
879
51470298 880 ssh->pktin.type = ssh->pktin.body[-1];
00db133f 881
a8327734 882 if (ssh->logctx)
883 log_packet(ssh->logctx,
884 PKT_INCOMING, ssh->pktin.type,
885 ssh1_pkt_type(ssh->pktin.type),
886 ssh->pktin.body, ssh->pktin.length);
00db133f 887
51470298 888 if (ssh->pktin.type == SSH1_SMSG_STDOUT_DATA ||
889 ssh->pktin.type == SSH1_SMSG_STDERR_DATA ||
890 ssh->pktin.type == SSH1_MSG_DEBUG ||
891 ssh->pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE ||
892 ssh->pktin.type == SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
893 long stringlen = GET_32BIT(ssh->pktin.body);
894 if (stringlen + 4 != ssh->pktin.length) {
6b5cf8b4 895 bombout(("Received data packet with bogus string length"));
7ffdbc1a 896 crStop(0);
32874aea 897 }
fb09bf1c 898 }
899
51470298 900 if (ssh->pktin.type == SSH1_MSG_DEBUG) {
fb09bf1c 901 /* log debug message */
eb4504cc 902 char buf[512];
51470298 903 int stringlen = GET_32BIT(ssh->pktin.body);
eb4504cc 904 strcpy(buf, "Remote debug message: ");
905 if (stringlen > 480)
906 stringlen = 480;
51470298 907 memcpy(buf + 8, ssh->pktin.body + 4, stringlen);
3d63ca2e 908 buf[8 + stringlen] = '\0';
fb09bf1c 909 logevent(buf);
910 goto next_packet;
51470298 911 } else if (ssh->pktin.type == SSH1_MSG_IGNORE) {
fb09bf1c 912 /* do nothing */
913 goto next_packet;
914 }
915
51470298 916 if (ssh->pktin.type == SSH1_MSG_DISCONNECT) {
38c4a8da 917 /* log reason code in disconnect message */
918 char buf[256];
51470298 919 unsigned msglen = GET_32BIT(ssh->pktin.body);
260f3dec 920 unsigned nowlen;
38c4a8da 921 strcpy(buf, "Remote sent disconnect: ");
922 nowlen = strlen(buf);
32874aea 923 if (msglen > sizeof(buf) - nowlen - 1)
924 msglen = sizeof(buf) - nowlen - 1;
51470298 925 memcpy(buf + nowlen, ssh->pktin.body + 4, msglen);
32874aea 926 buf[nowlen + msglen] = '\0';
247308b5 927 /* logevent(buf); (this is now done within the bombout macro) */
6b5cf8b4 928 bombout(("Server sent disconnect message:\n\"%s\"", buf+nowlen));
7ffdbc1a 929 crStop(0);
38c4a8da 930 }
931
fb09bf1c 932 crFinish(0);
933}
934
51470298 935static int ssh2_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
e5574168 936{
51470298 937 struct rdpkt2_state_tag *st = &ssh->rdpkt2_state;
e5574168 938
51470298 939 crBegin(ssh->ssh2_rdpkt_crstate);
e5574168 940
32874aea 941 next_packet:
51470298 942 ssh->pktin.type = 0;
943 ssh->pktin.length = 0;
944 if (ssh->sccipher)
945 st->cipherblk = ssh->sccipher->blksize;
e5574168 946 else
32874aea 947 st->cipherblk = 8;
960e736a 948 if (st->cipherblk < 8)
32874aea 949 st->cipherblk = 8;
960e736a 950
51470298 951 if (ssh->pktin.maxlen < st->cipherblk) {
952 ssh->pktin.maxlen = st->cipherblk;
3d88e64d 953 ssh->pktin.data = sresize(ssh->pktin.data, st->cipherblk + APIEXTRA,
954 unsigned char);
e5574168 955 }
956
957 /*
958 * Acquire and decrypt the first block of the packet. This will
959 * contain the length and padding details.
960 */
32874aea 961 for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) {
e5574168 962 while ((*datalen) == 0)
32874aea 963 crReturn(st->cipherblk - st->i);
51470298 964 ssh->pktin.data[st->i] = *(*data)++;
32874aea 965 (*datalen)--;
e5574168 966 }
4252c9cc 967
51470298 968 if (ssh->sccipher)
371e569c 969 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
970 ssh->pktin.data, st->cipherblk);
e5574168 971
972 /*
973 * Now get the length and padding figures.
974 */
51470298 975 st->len = GET_32BIT(ssh->pktin.data);
976 st->pad = ssh->pktin.data[4];
e5574168 977
978 /*
717dc483 979 * _Completely_ silly lengths should be stomped on before they
980 * do us any more damage.
981 */
982 if (st->len < 0 || st->pad < 0 || st->len + st->pad < 0) {
6b5cf8b4 983 bombout(("Incoming packet was garbled on decryption"));
7ffdbc1a 984 crStop(0);
717dc483 985 }
986
987 /*
e5574168 988 * This enables us to deduce the payload length.
989 */
960e736a 990 st->payload = st->len - st->pad - 1;
e5574168 991
51470298 992 ssh->pktin.length = st->payload + 5;
e5574168 993
994 /*
995 * So now we can work out the total packet length.
996 */
960e736a 997 st->packetlen = st->len + 4;
51470298 998 st->maclen = ssh->scmac ? ssh->scmac->len : 0;
e5574168 999
1000 /*
1001 * Adjust memory allocation if packet is too big.
1002 */
51470298 1003 if (ssh->pktin.maxlen < st->packetlen + st->maclen) {
1004 ssh->pktin.maxlen = st->packetlen + st->maclen;
3d88e64d 1005 ssh->pktin.data = sresize(ssh->pktin.data,
1006 ssh->pktin.maxlen + APIEXTRA,
1007 unsigned char);
e5574168 1008 }
1009
1010 /*
1011 * Read and decrypt the remainder of the packet.
1012 */
32874aea 1013 for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen;
1014 st->i++) {
e5574168 1015 while ((*datalen) == 0)
960e736a 1016 crReturn(st->packetlen + st->maclen - st->i);
51470298 1017 ssh->pktin.data[st->i] = *(*data)++;
32874aea 1018 (*datalen)--;
e5574168 1019 }
1020 /* Decrypt everything _except_ the MAC. */
51470298 1021 if (ssh->sccipher)
371e569c 1022 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
1023 ssh->pktin.data + st->cipherblk,
51470298 1024 st->packetlen - st->cipherblk);
e5574168 1025
1026 /*
1027 * Check the MAC.
1028 */
51470298 1029 if (ssh->scmac
e0e1a00d 1030 && !ssh->scmac->verify(ssh->sc_mac_ctx, ssh->pktin.data, st->len + 4,
51470298 1031 st->incoming_sequence)) {
6b5cf8b4 1032 bombout(("Incorrect MAC received on packet"));
7ffdbc1a 1033 crStop(0);
8d5de777 1034 }
32874aea 1035 st->incoming_sequence++; /* whether or not we MACed */
e5574168 1036
4ba9b64b 1037 /*
1038 * Decompress packet payload.
1039 */
1040 {
1041 unsigned char *newpayload;
1042 int newlen;
51470298 1043 if (ssh->sccomp &&
5366aed8 1044 ssh->sccomp->decompress(ssh->sc_comp_ctx,
1045 ssh->pktin.data + 5, ssh->pktin.length - 5,
51470298 1046 &newpayload, &newlen)) {
1047 if (ssh->pktin.maxlen < newlen + 5) {
1048 ssh->pktin.maxlen = newlen + 5;
3d88e64d 1049 ssh->pktin.data = sresize(ssh->pktin.data,
1050 ssh->pktin.maxlen + APIEXTRA,
1051 unsigned char);
4ba9b64b 1052 }
51470298 1053 ssh->pktin.length = 5 + newlen;
1054 memcpy(ssh->pktin.data + 5, newpayload, newlen);
dcbde236 1055 sfree(newpayload);
4ba9b64b 1056 }
1057 }
1058
51470298 1059 ssh->pktin.savedpos = 6;
1060 ssh->pktin.type = ssh->pktin.data[5];
e5574168 1061
a8327734 1062 if (ssh->logctx)
1063 log_packet(ssh->logctx, PKT_INCOMING, ssh->pktin.type,
1064 ssh2_pkt_type(ssh->pkt_ctx, ssh->pktin.type),
1065 ssh->pktin.data+6, ssh->pktin.length-6);
00db133f 1066
51470298 1067 switch (ssh->pktin.type) {
3d63ca2e 1068 /*
1069 * These packets we must handle instantly.
1070 */
1071 case SSH2_MSG_DISCONNECT:
1072 {
1073 /* log reason code in disconnect message */
57356d63 1074 char *buf;
1075 int nowlen;
51470298 1076 int reason = GET_32BIT(ssh->pktin.data + 6);
1077 unsigned msglen = GET_32BIT(ssh->pktin.data + 10);
57356d63 1078
3d63ca2e 1079 if (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) {
57356d63 1080 buf = dupprintf("Received disconnect message (%s)",
1081 ssh2_disconnect_reasons[reason]);
3d63ca2e 1082 } else {
57356d63 1083 buf = dupprintf("Received disconnect message (unknown"
1084 " type %d)", reason);
3d63ca2e 1085 }
1086 logevent(buf);
57356d63 1087 sfree(buf);
1088 buf = dupprintf("Disconnection message text: %n%.*s",
33b82b22 1089 &nowlen, msglen, ssh->pktin.data + 14);
3d63ca2e 1090 logevent(buf);
6b5cf8b4 1091 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
3d63ca2e 1092 reason,
1093 (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) ?
1094 ssh2_disconnect_reasons[reason] : "unknown",
1095 buf+nowlen));
57356d63 1096 sfree(buf);
7ffdbc1a 1097 crStop(0);
3d63ca2e 1098 }
1099 break;
1100 case SSH2_MSG_IGNORE:
1101 goto next_packet;
1102 case SSH2_MSG_DEBUG:
1103 {
1104 /* log the debug message */
1105 char buf[512];
51470298 1106 /* int display = ssh->pktin.body[6]; */
1107 int stringlen = GET_32BIT(ssh->pktin.data+7);
3d63ca2e 1108 int prefix;
1109 strcpy(buf, "Remote debug message: ");
1110 prefix = strlen(buf);
51470298 1111 if (stringlen > (int)(sizeof(buf)-prefix-1))
3d63ca2e 1112 stringlen = sizeof(buf)-prefix-1;
51470298 1113 memcpy(buf + prefix, ssh->pktin.data + 11, stringlen);
3d63ca2e 1114 buf[prefix + stringlen] = '\0';
1115 logevent(buf);
38c4a8da 1116 }
3d63ca2e 1117 goto next_packet; /* FIXME: print the debug message */
1118
1119 /*
1120 * These packets we need do nothing about here.
1121 */
1122 case SSH2_MSG_UNIMPLEMENTED:
1123 case SSH2_MSG_SERVICE_REQUEST:
1124 case SSH2_MSG_SERVICE_ACCEPT:
1125 case SSH2_MSG_KEXINIT:
1126 case SSH2_MSG_NEWKEYS:
1127 case SSH2_MSG_KEXDH_INIT:
1128 case SSH2_MSG_KEXDH_REPLY:
1129 /* case SSH2_MSG_KEX_DH_GEX_REQUEST: duplicate case value */
1130 /* case SSH2_MSG_KEX_DH_GEX_GROUP: duplicate case value */
1131 case SSH2_MSG_KEX_DH_GEX_INIT:
1132 case SSH2_MSG_KEX_DH_GEX_REPLY:
1133 case SSH2_MSG_USERAUTH_REQUEST:
1134 case SSH2_MSG_USERAUTH_FAILURE:
1135 case SSH2_MSG_USERAUTH_SUCCESS:
1136 case SSH2_MSG_USERAUTH_BANNER:
1137 case SSH2_MSG_USERAUTH_PK_OK:
1138 /* case SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: duplicate case value */
1139 /* case SSH2_MSG_USERAUTH_INFO_REQUEST: duplicate case value */
1140 case SSH2_MSG_USERAUTH_INFO_RESPONSE:
1141 case SSH2_MSG_GLOBAL_REQUEST:
1142 case SSH2_MSG_REQUEST_SUCCESS:
1143 case SSH2_MSG_REQUEST_FAILURE:
1144 case SSH2_MSG_CHANNEL_OPEN:
1145 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
1146 case SSH2_MSG_CHANNEL_OPEN_FAILURE:
1147 case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
1148 case SSH2_MSG_CHANNEL_DATA:
1149 case SSH2_MSG_CHANNEL_EXTENDED_DATA:
1150 case SSH2_MSG_CHANNEL_EOF:
1151 case SSH2_MSG_CHANNEL_CLOSE:
1152 case SSH2_MSG_CHANNEL_REQUEST:
1153 case SSH2_MSG_CHANNEL_SUCCESS:
1154 case SSH2_MSG_CHANNEL_FAILURE:
1155 break;
1156
1157 /*
1158 * For anything else we send SSH2_MSG_UNIMPLEMENTED.
1159 */
1160 default:
51470298 1161 ssh2_pkt_init(ssh, SSH2_MSG_UNIMPLEMENTED);
1162 ssh2_pkt_adduint32(ssh, st->incoming_sequence - 1);
1163 ssh2_pkt_send(ssh);
3d63ca2e 1164 break;
38c4a8da 1165 }
1166
e5574168 1167 crFinish(0);
1168}
1169
51470298 1170static void ssh1_pktout_size(Ssh ssh, int len)
32874aea 1171{
374330e2 1172 int pad, biglen;
1173
1174 len += 5; /* type and CRC */
32874aea 1175 pad = 8 - (len % 8);
374330e2 1176 biglen = len + pad;
1177
51470298 1178 ssh->pktout.length = len - 5;
1179 if (ssh->pktout.maxlen < biglen) {
1180 ssh->pktout.maxlen = biglen;
8f203108 1181#ifdef MSCRYPTOAPI
fb09bf1c 1182 /* Allocate enough buffer space for extra block
8f203108 1183 * for MS CryptEncrypt() */
3d88e64d 1184 ssh->pktout.data = sresize(ssh->pktout.data, biglen + 12,
1185 unsigned char);
8f203108 1186#else
3d88e64d 1187 ssh->pktout.data = sresize(ssh->pktout.data, biglen + 4,
1188 unsigned char);
8f203108 1189#endif
374330e2 1190 }
51470298 1191 ssh->pktout.body = ssh->pktout.data + 4 + pad + 1;
4ba9b64b 1192}
374330e2 1193
51470298 1194static void s_wrpkt_start(Ssh ssh, int type, int len)
32874aea 1195{
51470298 1196 ssh1_pktout_size(ssh, len);
1197 ssh->pktout.type = type;
374330e2 1198}
1199
51470298 1200static int s_wrpkt_prepare(Ssh ssh)
32874aea 1201{
fd7a4aad 1202 int pad, biglen, i;
374330e2 1203 unsigned long crc;
fd7a4aad 1204#ifdef __SC__
1205 /*
1206 * XXX various versions of SC (including 8.8.4) screw up the
1207 * register allocation in this function and use the same register
1208 * (D6) for len and as a temporary, with predictable results. The
1209 * following sledgehammer prevents this.
1210 */
1211 volatile
1212#endif
1213 int len;
374330e2 1214
51470298 1215 ssh->pktout.body[-1] = ssh->pktout.type;
4ba9b64b 1216
a8327734 1217 if (ssh->logctx)
1218 log_packet(ssh->logctx, PKT_OUTGOING, ssh->pktout.type,
1219 ssh1_pkt_type(ssh->pktout.type),
1220 ssh->pktout.body, ssh->pktout.length);
00db133f 1221
51470298 1222 if (ssh->v1_compressing) {
4ba9b64b 1223 unsigned char *compblk;
1224 int complen;
5366aed8 1225 zlib_compress_block(ssh->cs_comp_ctx,
1226 ssh->pktout.body - 1, ssh->pktout.length + 1,
4ba9b64b 1227 &compblk, &complen);
51470298 1228 ssh1_pktout_size(ssh, complen - 1);
1229 memcpy(ssh->pktout.body - 1, compblk, complen);
dcbde236 1230 sfree(compblk);
4ba9b64b 1231 }
1232
51470298 1233 len = ssh->pktout.length + 5; /* type and CRC */
32874aea 1234 pad = 8 - (len % 8);
374330e2 1235 biglen = len + pad;
1236
32874aea 1237 for (i = 0; i < pad; i++)
51470298 1238 ssh->pktout.data[i + 4] = random_byte();
1239 crc = crc32(ssh->pktout.data + 4, biglen - 4);
1240 PUT_32BIT(ssh->pktout.data + biglen, crc);
1241 PUT_32BIT(ssh->pktout.data, len);
374330e2 1242
51470298 1243 if (ssh->cipher)
371e569c 1244 ssh->cipher->encrypt(ssh->v1_cipher_ctx, ssh->pktout.data + 4, biglen);
374330e2 1245
32874aea 1246 return biglen + 4;
39065bed 1247}
1248
51470298 1249static void s_wrpkt(Ssh ssh)
32874aea 1250{
5471d09a 1251 int len, backlog;
51470298 1252 len = s_wrpkt_prepare(ssh);
d8baa528 1253 backlog = sk_write(ssh->s, (char *)ssh->pktout.data, len);
5471d09a 1254 if (backlog > SSH_MAX_BACKLOG)
51470298 1255 ssh_throttle_all(ssh, 1, backlog);
39065bed 1256}
1257
51470298 1258static void s_wrpkt_defer(Ssh ssh)
32874aea 1259{
39065bed 1260 int len;
51470298 1261 len = s_wrpkt_prepare(ssh);
1262 if (ssh->deferred_len + len > ssh->deferred_size) {
1263 ssh->deferred_size = ssh->deferred_len + len + 128;
3d88e64d 1264 ssh->deferred_send_data = sresize(ssh->deferred_send_data,
1265 ssh->deferred_size,
1266 unsigned char);
39065bed 1267 }
51470298 1268 memcpy(ssh->deferred_send_data + ssh->deferred_len, ssh->pktout.data, len);
1269 ssh->deferred_len += len;
374330e2 1270}
1271
fb09bf1c 1272/*
39065bed 1273 * Construct a packet with the specified contents.
fb09bf1c 1274 */
51470298 1275static void construct_packet(Ssh ssh, int pkttype, va_list ap1, va_list ap2)
fb09bf1c 1276{
fb09bf1c 1277 unsigned char *p, *argp, argchar;
1278 unsigned long argint;
1279 int pktlen, argtype, arglen;
7cca0d81 1280 Bignum bn;
fb09bf1c 1281
1282 pktlen = 0;
39065bed 1283 while ((argtype = va_arg(ap1, int)) != PKT_END) {
fb09bf1c 1284 switch (argtype) {
1285 case PKT_INT:
39065bed 1286 (void) va_arg(ap1, int);
fb09bf1c 1287 pktlen += 4;
1288 break;
1289 case PKT_CHAR:
1ec39246 1290 (void) va_arg(ap1, int);
fb09bf1c 1291 pktlen++;
1292 break;
1293 case PKT_DATA:
39065bed 1294 (void) va_arg(ap1, unsigned char *);
1295 arglen = va_arg(ap1, int);
fb09bf1c 1296 pktlen += arglen;
1297 break;
1298 case PKT_STR:
39065bed 1299 argp = va_arg(ap1, unsigned char *);
d8baa528 1300 arglen = strlen((char *)argp);
fb09bf1c 1301 pktlen += 4 + arglen;
1302 break;
7cca0d81 1303 case PKT_BIGNUM:
39065bed 1304 bn = va_arg(ap1, Bignum);
32874aea 1305 pktlen += ssh1_bignum_length(bn);
7cca0d81 1306 break;
fb09bf1c 1307 default:
1308 assert(0);
1309 }
1310 }
fb09bf1c 1311
51470298 1312 s_wrpkt_start(ssh, pkttype, pktlen);
1313 p = ssh->pktout.body;
fb09bf1c 1314
39065bed 1315 while ((argtype = va_arg(ap2, int)) != PKT_END) {
fb09bf1c 1316 switch (argtype) {
1317 case PKT_INT:
39065bed 1318 argint = va_arg(ap2, int);
fb09bf1c 1319 PUT_32BIT(p, argint);
1320 p += 4;
1321 break;
1322 case PKT_CHAR:
1ec39246 1323 argchar = (unsigned char) va_arg(ap2, int);
fb09bf1c 1324 *p = argchar;
1325 p++;
1326 break;
1327 case PKT_DATA:
39065bed 1328 argp = va_arg(ap2, unsigned char *);
1329 arglen = va_arg(ap2, int);
fb09bf1c 1330 memcpy(p, argp, arglen);
1331 p += arglen;
1332 break;
1333 case PKT_STR:
39065bed 1334 argp = va_arg(ap2, unsigned char *);
d8baa528 1335 arglen = strlen((char *)argp);
fb09bf1c 1336 PUT_32BIT(p, arglen);
1337 memcpy(p + 4, argp, arglen);
1338 p += 4 + arglen;
1339 break;
7cca0d81 1340 case PKT_BIGNUM:
39065bed 1341 bn = va_arg(ap2, Bignum);
32874aea 1342 p += ssh1_write_bignum(p, bn);
7cca0d81 1343 break;
fb09bf1c 1344 }
1345 }
39065bed 1346}
fb09bf1c 1347
51470298 1348static void send_packet(Ssh ssh, int pkttype, ...)
32874aea 1349{
39065bed 1350 va_list ap1, ap2;
1351 va_start(ap1, pkttype);
1352 va_start(ap2, pkttype);
51470298 1353 construct_packet(ssh, pkttype, ap1, ap2);
1354 s_wrpkt(ssh);
fb09bf1c 1355}
1356
51470298 1357static void defer_packet(Ssh ssh, int pkttype, ...)
32874aea 1358{
39065bed 1359 va_list ap1, ap2;
1360 va_start(ap1, pkttype);
1361 va_start(ap2, pkttype);
51470298 1362 construct_packet(ssh, pkttype, ap1, ap2);
1363 s_wrpkt_defer(ssh);
39065bed 1364}
1365
32874aea 1366static int ssh_versioncmp(char *a, char *b)
1367{
9697bfd2 1368 char *ae, *be;
1369 unsigned long av, bv;
1370
43aa02a7 1371 av = strtoul(a, &ae, 10);
1372 bv = strtoul(b, &be, 10);
32874aea 1373 if (av != bv)
1374 return (av < bv ? -1 : +1);
1375 if (*ae == '.')
1376 ae++;
1377 if (*be == '.')
1378 be++;
43aa02a7 1379 av = strtoul(ae, &ae, 10);
1380 bv = strtoul(be, &be, 10);
32874aea 1381 if (av != bv)
1382 return (av < bv ? -1 : +1);
9697bfd2 1383 return 0;
1384}
1385
e5574168 1386/*
a92dd380 1387 * Utility routines for putting an SSH-protocol `string' and
1388 * `uint32' into a SHA state.
e5574168 1389 */
1390#include <stdio.h>
32874aea 1391static void sha_string(SHA_State * s, void *str, int len)
1392{
e5574168 1393 unsigned char lenblk[4];
e5574168 1394 PUT_32BIT(lenblk, len);
e5574168 1395 SHA_Bytes(s, lenblk, 4);
e5574168 1396 SHA_Bytes(s, str, len);
1397}
1398
32874aea 1399static void sha_uint32(SHA_State * s, unsigned i)
1400{
a92dd380 1401 unsigned char intblk[4];
1402 PUT_32BIT(intblk, i);
1403 SHA_Bytes(s, intblk, 4);
1404}
1405
7cca0d81 1406/*
1407 * SSH2 packet construction functions.
1408 */
51470298 1409static void ssh2_pkt_ensure(Ssh ssh, int length)
32874aea 1410{
51470298 1411 if (ssh->pktout.maxlen < length) {
1412 ssh->pktout.maxlen = length + 256;
3d88e64d 1413 ssh->pktout.data = sresize(ssh->pktout.data,
1414 ssh->pktout.maxlen + APIEXTRA,
1415 unsigned char);
51470298 1416 if (!ssh->pktout.data)
32874aea 1417 fatalbox("Out of memory");
7cca0d81 1418 }
783415f8 1419}
51470298 1420static void ssh2_pkt_adddata(Ssh ssh, void *data, int len)
32874aea 1421{
51470298 1422 ssh->pktout.length += len;
1423 ssh2_pkt_ensure(ssh, ssh->pktout.length);
1424 memcpy(ssh->pktout.data + ssh->pktout.length - len, data, len);
7cca0d81 1425}
51470298 1426static void ssh2_pkt_addbyte(Ssh ssh, unsigned char byte)
32874aea 1427{
51470298 1428 ssh2_pkt_adddata(ssh, &byte, 1);
7cca0d81 1429}
51470298 1430static void ssh2_pkt_init(Ssh ssh, int pkt_type)
32874aea 1431{
51470298 1432 ssh->pktout.length = 5;
1433 ssh2_pkt_addbyte(ssh, (unsigned char) pkt_type);
7cca0d81 1434}
51470298 1435static void ssh2_pkt_addbool(Ssh ssh, unsigned char value)
32874aea 1436{
51470298 1437 ssh2_pkt_adddata(ssh, &value, 1);
7cca0d81 1438}
51470298 1439static void ssh2_pkt_adduint32(Ssh ssh, unsigned long value)
32874aea 1440{
7cca0d81 1441 unsigned char x[4];
1442 PUT_32BIT(x, value);
51470298 1443 ssh2_pkt_adddata(ssh, x, 4);
7cca0d81 1444}
51470298 1445static void ssh2_pkt_addstring_start(Ssh ssh)
32874aea 1446{
51470298 1447 ssh2_pkt_adduint32(ssh, 0);
1448 ssh->pktout.savedpos = ssh->pktout.length;
7cca0d81 1449}
51470298 1450static void ssh2_pkt_addstring_str(Ssh ssh, char *data)
32874aea 1451{
51470298 1452 ssh2_pkt_adddata(ssh, data, strlen(data));
1453 PUT_32BIT(ssh->pktout.data + ssh->pktout.savedpos - 4,
1454 ssh->pktout.length - ssh->pktout.savedpos);
7cca0d81 1455}
51470298 1456static void ssh2_pkt_addstring_data(Ssh ssh, char *data, int len)
32874aea 1457{
51470298 1458 ssh2_pkt_adddata(ssh, data, len);
1459 PUT_32BIT(ssh->pktout.data + ssh->pktout.savedpos - 4,
1460 ssh->pktout.length - ssh->pktout.savedpos);
7cca0d81 1461}
51470298 1462static void ssh2_pkt_addstring(Ssh ssh, char *data)
32874aea 1463{
51470298 1464 ssh2_pkt_addstring_start(ssh);
1465 ssh2_pkt_addstring_str(ssh, data);
7cca0d81 1466}
d8baa528 1467static unsigned char *ssh2_mpint_fmt(Bignum b, int *len)
32874aea 1468{
7cca0d81 1469 unsigned char *p;
32874aea 1470 int i, n = (bignum_bitcount(b) + 7) / 8;
3d88e64d 1471 p = snewn(n + 1, unsigned char);
7cca0d81 1472 if (!p)
32874aea 1473 fatalbox("out of memory");
7cca0d81 1474 p[0] = 0;
3709bfe9 1475 for (i = 1; i <= n; i++)
32874aea 1476 p[i] = bignum_byte(b, n - i);
7cca0d81 1477 i = 0;
32874aea 1478 while (i <= n && p[i] == 0 && (p[i + 1] & 0x80) == 0)
1479 i++;
1480 memmove(p, p + i, n + 1 - i);
1481 *len = n + 1 - i;
7cca0d81 1482 return p;
1483}
51470298 1484static void ssh2_pkt_addmp(Ssh ssh, Bignum b)
32874aea 1485{
7cca0d81 1486 unsigned char *p;
1487 int len;
1488 p = ssh2_mpint_fmt(b, &len);
51470298 1489 ssh2_pkt_addstring_start(ssh);
d8baa528 1490 ssh2_pkt_addstring_data(ssh, (char *)p, len);
dcbde236 1491 sfree(p);
7cca0d81 1492}
b185170a 1493
1494/*
1495 * Construct an SSH2 final-form packet: compress it, encrypt it,
1496 * put the MAC on it. Final packet, ready to be sent, is stored in
51470298 1497 * ssh->pktout.data. Total length is returned.
b185170a 1498 */
51470298 1499static int ssh2_pkt_construct(Ssh ssh)
32874aea 1500{
7cca0d81 1501 int cipherblk, maclen, padding, i;
7cca0d81 1502
a8327734 1503 if (ssh->logctx)
1504 log_packet(ssh->logctx, PKT_OUTGOING, ssh->pktout.data[5],
1505 ssh2_pkt_type(ssh->pkt_ctx, ssh->pktout.data[5]),
1506 ssh->pktout.data + 6, ssh->pktout.length - 6);
00db133f 1507
7cca0d81 1508 /*
4ba9b64b 1509 * Compress packet payload.
1510 */
4ba9b64b 1511 {
1512 unsigned char *newpayload;
1513 int newlen;
51470298 1514 if (ssh->cscomp &&
5366aed8 1515 ssh->cscomp->compress(ssh->cs_comp_ctx, ssh->pktout.data + 5,
1516 ssh->pktout.length - 5,
51470298 1517 &newpayload, &newlen)) {
1518 ssh->pktout.length = 5;
1519 ssh2_pkt_adddata(ssh, newpayload, newlen);
dcbde236 1520 sfree(newpayload);
4ba9b64b 1521 }
1522 }
1523
1524 /*
7cca0d81 1525 * Add padding. At least four bytes, and must also bring total
1526 * length (minus MAC) up to a multiple of the block size.
1527 */
51470298 1528 cipherblk = ssh->cscipher ? ssh->cscipher->blksize : 8; /* block size */
32874aea 1529 cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
7cca0d81 1530 padding = 4;
32874aea 1531 padding +=
51470298 1532 (cipherblk - (ssh->pktout.length + padding) % cipherblk) % cipherblk;
1533 maclen = ssh->csmac ? ssh->csmac->len : 0;
1534 ssh2_pkt_ensure(ssh, ssh->pktout.length + padding + maclen);
1535 ssh->pktout.data[4] = padding;
7cca0d81 1536 for (i = 0; i < padding; i++)
51470298 1537 ssh->pktout.data[ssh->pktout.length + i] = random_byte();
1538 PUT_32BIT(ssh->pktout.data, ssh->pktout.length + padding - 4);
1539 if (ssh->csmac)
e0e1a00d 1540 ssh->csmac->generate(ssh->cs_mac_ctx, ssh->pktout.data,
1541 ssh->pktout.length + padding,
51470298 1542 ssh->v2_outgoing_sequence);
1543 ssh->v2_outgoing_sequence++; /* whether or not we MACed */
1544
1545 if (ssh->cscipher)
371e569c 1546 ssh->cscipher->encrypt(ssh->cs_cipher_ctx,
1547 ssh->pktout.data, ssh->pktout.length + padding);
51470298 1548
1549 /* Ready-to-send packet starts at ssh->pktout.data. We return length. */
1550 return ssh->pktout.length + padding + maclen;
b185170a 1551}
1552
1553/*
1554 * Construct and send an SSH2 packet immediately.
1555 */
51470298 1556static void ssh2_pkt_send(Ssh ssh)
32874aea 1557{
5471d09a 1558 int len;
1559 int backlog;
51470298 1560 len = ssh2_pkt_construct(ssh);
d8baa528 1561 backlog = sk_write(ssh->s, (char *)ssh->pktout.data, len);
5471d09a 1562 if (backlog > SSH_MAX_BACKLOG)
51470298 1563 ssh_throttle_all(ssh, 1, backlog);
b185170a 1564}
1565
1566/*
1567 * Construct an SSH2 packet and add it to a deferred data block.
1568 * Useful for sending multiple packets in a single sk_write() call,
1569 * to prevent a traffic-analysing listener from being able to work
1570 * out the length of any particular packet (such as the password
1571 * packet).
1572 *
1573 * Note that because SSH2 sequence-numbers its packets, this can
1574 * NOT be used as an m4-style `defer' allowing packets to be
1575 * constructed in one order and sent in another.
1576 */
51470298 1577static void ssh2_pkt_defer(Ssh ssh)
32874aea 1578{
51470298 1579 int len = ssh2_pkt_construct(ssh);
1580 if (ssh->deferred_len + len > ssh->deferred_size) {
1581 ssh->deferred_size = ssh->deferred_len + len + 128;
3d88e64d 1582 ssh->deferred_send_data = sresize(ssh->deferred_send_data,
1583 ssh->deferred_size,
1584 unsigned char);
b185170a 1585 }
51470298 1586 memcpy(ssh->deferred_send_data + ssh->deferred_len, ssh->pktout.data, len);
1587 ssh->deferred_len += len;
b185170a 1588}
1589
1590/*
1591 * Send the whole deferred data block constructed by
39065bed 1592 * ssh2_pkt_defer() or SSH1's defer_packet().
b185170a 1593 */
51470298 1594static void ssh_pkt_defersend(Ssh ssh)
32874aea 1595{
5471d09a 1596 int backlog;
d8baa528 1597 backlog = sk_write(ssh->s, (char *)ssh->deferred_send_data,
1598 ssh->deferred_len);
51470298 1599 ssh->deferred_len = ssh->deferred_size = 0;
1600 sfree(ssh->deferred_send_data);
1601 ssh->deferred_send_data = NULL;
5471d09a 1602 if (backlog > SSH_MAX_BACKLOG)
51470298 1603 ssh_throttle_all(ssh, 1, backlog);
7cca0d81 1604}
1605
1606#if 0
32874aea 1607void bndebug(char *string, Bignum b)
1608{
7cca0d81 1609 unsigned char *p;
1610 int i, len;
1611 p = ssh2_mpint_fmt(b, &len);
1612 debug(("%s", string));
1613 for (i = 0; i < len; i++)
32874aea 1614 debug((" %02x", p[i]));
765c4200 1615 debug(("\n"));
dcbde236 1616 sfree(p);
7cca0d81 1617}
1618#endif
1619
32874aea 1620static void sha_mpint(SHA_State * s, Bignum b)
1621{
7cca0d81 1622 unsigned char *p;
1623 int len;
1624 p = ssh2_mpint_fmt(b, &len);
1625 sha_string(s, p, len);
dcbde236 1626 sfree(p);
7cca0d81 1627}
1628
1629/*
1630 * SSH2 packet decode functions.
1631 */
51470298 1632static unsigned long ssh2_pkt_getuint32(Ssh ssh)
32874aea 1633{
7cca0d81 1634 unsigned long value;
51470298 1635 if (ssh->pktin.length - ssh->pktin.savedpos < 4)
32874aea 1636 return 0; /* arrgh, no way to decline (FIXME?) */
51470298 1637 value = GET_32BIT(ssh->pktin.data + ssh->pktin.savedpos);
1638 ssh->pktin.savedpos += 4;
7cca0d81 1639 return value;
1640}
51470298 1641static int ssh2_pkt_getbool(Ssh ssh)
32874aea 1642{
65a22376 1643 unsigned long value;
51470298 1644 if (ssh->pktin.length - ssh->pktin.savedpos < 1)
32874aea 1645 return 0; /* arrgh, no way to decline (FIXME?) */
51470298 1646 value = ssh->pktin.data[ssh->pktin.savedpos] != 0;
1647 ssh->pktin.savedpos++;
65a22376 1648 return value;
1649}
51470298 1650static void ssh2_pkt_getstring(Ssh ssh, char **p, int *length)
32874aea 1651{
57356d63 1652 int len;
7cca0d81 1653 *p = NULL;
45068b27 1654 *length = 0;
51470298 1655 if (ssh->pktin.length - ssh->pktin.savedpos < 4)
32874aea 1656 return;
57356d63 1657 len = GET_32BIT(ssh->pktin.data + ssh->pktin.savedpos);
1658 if (len < 0)
1659 return;
1660 *length = len;
51470298 1661 ssh->pktin.savedpos += 4;
1662 if (ssh->pktin.length - ssh->pktin.savedpos < *length)
32874aea 1663 return;
d8baa528 1664 *p = (char *)(ssh->pktin.data + ssh->pktin.savedpos);
51470298 1665 ssh->pktin.savedpos += *length;
7cca0d81 1666}
51470298 1667static Bignum ssh2_pkt_getmp(Ssh ssh)
32874aea 1668{
7cca0d81 1669 char *p;
3709bfe9 1670 int length;
7cca0d81 1671 Bignum b;
1672
51470298 1673 ssh2_pkt_getstring(ssh, &p, &length);
7cca0d81 1674 if (!p)
32874aea 1675 return NULL;
8d5de777 1676 if (p[0] & 0x80) {
6b5cf8b4 1677 bombout(("internal error: Can't handle negative mpints"));
32874aea 1678 return NULL;
8d5de777 1679 }
d8baa528 1680 b = bignum_from_bytes((unsigned char *)p, length);
7cca0d81 1681 return b;
1682}
1683
7d503c31 1684/*
1dd353b5 1685 * Helper function to add an SSH2 signature blob to a packet.
1686 * Expects to be shown the public key blob as well as the signature
1687 * blob. Normally works just like ssh2_pkt_addstring, but will
1688 * fiddle with the signature packet if necessary for
1689 * BUG_SSH2_RSA_PADDING.
1690 */
51470298 1691static void ssh2_add_sigblob(Ssh ssh, void *pkblob_v, int pkblob_len,
1dd353b5 1692 void *sigblob_v, int sigblob_len)
1693{
1694 unsigned char *pkblob = (unsigned char *)pkblob_v;
1695 unsigned char *sigblob = (unsigned char *)sigblob_v;
1696
1697 /* dmemdump(pkblob, pkblob_len); */
1698 /* dmemdump(sigblob, sigblob_len); */
1699
1700 /*
1701 * See if this is in fact an ssh-rsa signature and a buggy
1702 * server; otherwise we can just do this the easy way.
1703 */
51470298 1704 if ((ssh->remote_bugs & BUG_SSH2_RSA_PADDING) &&
1dd353b5 1705 (GET_32BIT(pkblob) == 7 && !memcmp(pkblob+4, "ssh-rsa", 7))) {
1706 int pos, len, siglen;
1707
1708 /*
1709 * Find the byte length of the modulus.
1710 */
1711
1712 pos = 4+7; /* skip over "ssh-rsa" */
1713 pos += 4 + GET_32BIT(pkblob+pos); /* skip over exponent */
1714 len = GET_32BIT(pkblob+pos); /* find length of modulus */
1715 pos += 4; /* find modulus itself */
1716 while (len > 0 && pkblob[pos] == 0)
1717 len--, pos++;
1718 /* debug(("modulus length is %d\n", len)); */
1719
1720 /*
1721 * Now find the signature integer.
1722 */
1723 pos = 4+7; /* skip over "ssh-rsa" */
1724 siglen = GET_32BIT(sigblob+pos);
1725 /* debug(("signature length is %d\n", siglen)); */
1726
1727 if (len != siglen) {
1728 unsigned char newlen[4];
51470298 1729 ssh2_pkt_addstring_start(ssh);
d8baa528 1730 ssh2_pkt_addstring_data(ssh, (char *)sigblob, pos);
1dd353b5 1731 /* dmemdump(sigblob, pos); */
1732 pos += 4; /* point to start of actual sig */
1733 PUT_32BIT(newlen, len);
d8baa528 1734 ssh2_pkt_addstring_data(ssh, (char *)newlen, 4);
1dd353b5 1735 /* dmemdump(newlen, 4); */
1736 newlen[0] = 0;
1737 while (len-- > siglen) {
d8baa528 1738 ssh2_pkt_addstring_data(ssh, (char *)newlen, 1);
1dd353b5 1739 /* dmemdump(newlen, 1); */
1740 }
d8baa528 1741 ssh2_pkt_addstring_data(ssh, (char *)(sigblob+pos), siglen);
1dd353b5 1742 /* dmemdump(sigblob+pos, siglen); */
1743 return;
1744 }
1745
1746 /* Otherwise fall through and do it the easy way. */
1747 }
1748
51470298 1749 ssh2_pkt_addstring_start(ssh);
d8baa528 1750 ssh2_pkt_addstring_data(ssh, (char *)sigblob, sigblob_len);
1dd353b5 1751}
1752
1753/*
7d503c31 1754 * Examine the remote side's version string and compare it against
1755 * a list of known buggy implementations.
1756 */
51470298 1757static void ssh_detect_bugs(Ssh ssh, char *vstring)
32874aea 1758{
1759 char *imp; /* pointer to implementation part */
7d503c31 1760 imp = vstring;
1761 imp += strcspn(imp, "-");
bd358db1 1762 if (*imp) imp++;
7d503c31 1763 imp += strcspn(imp, "-");
bd358db1 1764 if (*imp) imp++;
7d503c31 1765
51470298 1766 ssh->remote_bugs = 0;
7d503c31 1767
5ecd7ad0 1768 if (ssh->cfg.sshbug_ignore1 == FORCE_ON ||
1769 (ssh->cfg.sshbug_ignore1 == AUTO &&
2c9c6388 1770 (!strcmp(imp, "1.2.18") || !strcmp(imp, "1.2.19") ||
1771 !strcmp(imp, "1.2.20") || !strcmp(imp, "1.2.21") ||
1772 !strcmp(imp, "1.2.22") || !strcmp(imp, "Cisco-1.25")))) {
32874aea 1773 /*
1774 * These versions don't support SSH1_MSG_IGNORE, so we have
1775 * to use a different defence against password length
1776 * sniffing.
1777 */
51470298 1778 ssh->remote_bugs |= BUG_CHOKES_ON_SSH1_IGNORE;
32874aea 1779 logevent("We believe remote version has SSH1 ignore bug");
7d503c31 1780 }
1781
5ecd7ad0 1782 if (ssh->cfg.sshbug_plainpw1 == FORCE_ON ||
1783 (ssh->cfg.sshbug_plainpw1 == AUTO &&
2c9c6388 1784 (!strcmp(imp, "Cisco-1.25")))) {
bd358db1 1785 /*
1786 * These versions need a plain password sent; they can't
1787 * handle having a null and a random length of data after
1788 * the password.
1789 */
51470298 1790 ssh->remote_bugs |= BUG_NEEDS_SSH1_PLAIN_PASSWORD;
bd358db1 1791 logevent("We believe remote version needs a plain SSH1 password");
1792 }
1793
5ecd7ad0 1794 if (ssh->cfg.sshbug_rsa1 == FORCE_ON ||
1795 (ssh->cfg.sshbug_rsa1 == AUTO &&
2c9c6388 1796 (!strcmp(imp, "Cisco-1.25")))) {
0df73905 1797 /*
1798 * These versions apparently have no clue whatever about
1799 * RSA authentication and will panic and die if they see
1800 * an AUTH_RSA message.
1801 */
51470298 1802 ssh->remote_bugs |= BUG_CHOKES_ON_RSA;
0df73905 1803 logevent("We believe remote version can't handle RSA authentication");
1804 }
1805
5ecd7ad0 1806 if (ssh->cfg.sshbug_hmac2 == FORCE_ON ||
1807 (ssh->cfg.sshbug_hmac2 == AUTO &&
831301f6 1808 (wc_match("2.1.0*", imp) || wc_match("2.0.*", imp) ||
1809 wc_match("2.2.0*", imp) || wc_match("2.3.0*", imp) ||
1810 wc_match("2.1 *", imp)))) {
32874aea 1811 /*
1812 * These versions have the HMAC bug.
1813 */
51470298 1814 ssh->remote_bugs |= BUG_SSH2_HMAC;
32874aea 1815 logevent("We believe remote version has SSH2 HMAC bug");
7d503c31 1816 }
1dd353b5 1817
5ecd7ad0 1818 if (ssh->cfg.sshbug_derivekey2 == FORCE_ON ||
1819 (ssh->cfg.sshbug_derivekey2 == AUTO &&
2856a1b9 1820 (wc_match("2.0.0*", imp) || wc_match("2.0.10*", imp) ))) {
088bde77 1821 /*
1822 * These versions have the key-derivation bug (failing to
1823 * include the literal shared secret in the hashes that
1824 * generate the keys).
1825 */
51470298 1826 ssh->remote_bugs |= BUG_SSH2_DERIVEKEY;
088bde77 1827 logevent("We believe remote version has SSH2 key-derivation bug");
1828 }
1829
5ecd7ad0 1830 if (ssh->cfg.sshbug_rsapad2 == FORCE_ON ||
1831 (ssh->cfg.sshbug_rsapad2 == AUTO &&
831301f6 1832 (wc_match("OpenSSH_2.[5-9]*", imp) ||
1833 wc_match("OpenSSH_3.[0-2]*", imp)))) {
1dd353b5 1834 /*
1835 * These versions have the SSH2 RSA padding bug.
1836 */
51470298 1837 ssh->remote_bugs |= BUG_SSH2_RSA_PADDING;
1dd353b5 1838 logevent("We believe remote version has SSH2 RSA padding bug");
1839 }
8e975795 1840
dda87a28 1841 if (ssh->cfg.sshbug_pksessid2 == FORCE_ON ||
1842 (ssh->cfg.sshbug_pksessid2 == AUTO &&
1843 wc_match("OpenSSH_2.[0-2]*", imp))) {
1844 /*
1845 * These versions have the SSH2 session-ID bug in
1846 * public-key authentication.
1847 */
1848 ssh->remote_bugs |= BUG_SSH2_PK_SESSIONID;
1849 logevent("We believe remote version has SSH2 public-key-session-ID bug");
1850 }
1851
5ecd7ad0 1852 if (ssh->cfg.sshbug_dhgex2 == FORCE_ON) {
8e975795 1853 /*
831301f6 1854 * User specified the SSH2 DH GEX bug.
8e975795 1855 */
51470298 1856 ssh->remote_bugs |= BUG_SSH2_DH_GEX;
8e975795 1857 logevent("We believe remote version has SSH2 DH group exchange bug");
1858 }
7d503c31 1859}
1860
51470298 1861static int do_ssh_init(Ssh ssh, unsigned char c)
32874aea 1862{
51470298 1863 struct do_ssh_init_state {
1864 int vslen;
1865 char version[10];
1866 char *vstring;
1867 int vstrsize;
1868 int i;
1869 int proto1, proto2;
1870 };
1871 crState(do_ssh_init_state);
374330e2 1872
51470298 1873 crBegin(ssh->do_ssh_init_crstate);
8df7a775 1874
1875 /* Search for the string "SSH-" in the input. */
51470298 1876 s->i = 0;
8df7a775 1877 while (1) {
1878 static const int transS[] = { 1, 2, 2, 1 };
1879 static const int transH[] = { 0, 0, 3, 0 };
1880 static const int transminus[] = { 0, 0, 0, -1 };
32874aea 1881 if (c == 'S')
51470298 1882 s->i = transS[s->i];
32874aea 1883 else if (c == 'H')
51470298 1884 s->i = transH[s->i];
32874aea 1885 else if (c == '-')
51470298 1886 s->i = transminus[s->i];
32874aea 1887 else
51470298 1888 s->i = 0;
1889 if (s->i < 0)
8df7a775 1890 break;
1891 crReturn(1); /* get another character */
374330e2 1892 }
8df7a775 1893
51470298 1894 s->vstrsize = 16;
3d88e64d 1895 s->vstring = snewn(s->vstrsize, char);
51470298 1896 strcpy(s->vstring, "SSH-");
1897 s->vslen = 4;
1898 s->i = 0;
374330e2 1899 while (1) {
8df7a775 1900 crReturn(1); /* get another char */
51470298 1901 if (s->vslen >= s->vstrsize - 1) {
1902 s->vstrsize += 16;
3d88e64d 1903 s->vstring = sresize(s->vstring, s->vstrsize, char);
32874aea 1904 }
51470298 1905 s->vstring[s->vslen++] = c;
1906 if (s->i >= 0) {
374330e2 1907 if (c == '-') {
51470298 1908 s->version[s->i] = '\0';
1909 s->i = -1;
1910 } else if (s->i < sizeof(s->version) - 1)
1911 s->version[s->i++] = c;
c4ffc4d0 1912 } else if (c == '\012')
374330e2 1913 break;
1914 }
1915
51470298 1916 ssh->agentfwd_enabled = FALSE;
1917 ssh->rdpkt2_state.incoming_sequence = 0;
960e736a 1918
51470298 1919 s->vstring[s->vslen] = 0;
1920 s->vstring[strcspn(s->vstring, "\r\n")] = '\0';/* remove EOL chars */
1921 {
1922 char *vlog;
3d88e64d 1923 vlog = snewn(20 + s->vslen, char);
51470298 1924 sprintf(vlog, "Server version: %s", s->vstring);
1925 logevent(vlog);
1926 sfree(vlog);
1927 }
1928 ssh_detect_bugs(ssh, s->vstring);
c5e9c988 1929
adf799dd 1930 /*
38d228a2 1931 * Decide which SSH protocol version to support.
adf799dd 1932 */
38d228a2 1933
1934 /* Anything strictly below "2.0" means protocol 1 is supported. */
51470298 1935 s->proto1 = ssh_versioncmp(s->version, "2.0") < 0;
38d228a2 1936 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
51470298 1937 s->proto2 = ssh_versioncmp(s->version, "1.99") >= 0;
38d228a2 1938
86916870 1939 if (ssh->cfg.sshprot == 0 && !s->proto1) {
6b5cf8b4 1940 bombout(("SSH protocol version 1 required by user but not provided by server"));
7ffdbc1a 1941 crStop(0);
38d228a2 1942 }
86916870 1943 if (ssh->cfg.sshprot == 3 && !s->proto2) {
6b5cf8b4 1944 bombout(("SSH protocol version 2 required by user but not provided by server"));
7ffdbc1a 1945 crStop(0);
38d228a2 1946 }
1947
86916870 1948 if (s->proto2 && (ssh->cfg.sshprot >= 2 || !s->proto1)) {
32874aea 1949 /*
38d228a2 1950 * Use v2 protocol.
32874aea 1951 */
1952 char verstring[80], vlog[100];
1953 sprintf(verstring, "SSH-2.0-%s", sshver);
51470298 1954 SHA_Init(&ssh->exhashbase);
32874aea 1955 /*
1956 * Hash our version string and their version string.
1957 */
51470298 1958 sha_string(&ssh->exhashbase, verstring, strlen(verstring));
1959 sha_string(&ssh->exhashbase, s->vstring, strcspn(s->vstring, "\r\n"));
32874aea 1960 sprintf(vlog, "We claim version: %s", verstring);
1961 logevent(vlog);
c4ffc4d0 1962 strcat(verstring, "\012");
32874aea 1963 logevent("Using SSH protocol version 2");
51470298 1964 sk_write(ssh->s, verstring, strlen(verstring));
1965 ssh->protocol = ssh2_protocol;
1966 ssh->version = 2;
1967 ssh->s_rdpkt = ssh2_rdpkt;
e5574168 1968 } else {
32874aea 1969 /*
38d228a2 1970 * Use v1 protocol.
32874aea 1971 */
1972 char verstring[80], vlog[100];
1973 sprintf(verstring, "SSH-%s-%s",
51470298 1974 (ssh_versioncmp(s->version, "1.5") <= 0 ? s->version : "1.5"),
32874aea 1975 sshver);
1976 sprintf(vlog, "We claim version: %s", verstring);
1977 logevent(vlog);
c4ffc4d0 1978 strcat(verstring, "\012");
759712a6 1979
32874aea 1980 logevent("Using SSH protocol version 1");
51470298 1981 sk_write(ssh->s, verstring, strlen(verstring));
1982 ssh->protocol = ssh1_protocol;
1983 ssh->version = 1;
1984 ssh->s_rdpkt = ssh1_rdpkt;
e5574168 1985 }
125105d1 1986 update_specials_menu(ssh->frontend);
51470298 1987 ssh->state = SSH_STATE_BEFORE_SIZE;
8df7a775 1988
51470298 1989 sfree(s->vstring);
50526e47 1990
8df7a775 1991 crFinish(0);
1992}
1993
51470298 1994static void ssh_gotdata(Ssh ssh, unsigned char *data, int datalen)
8df7a775 1995{
51470298 1996 crBegin(ssh->ssh_gotdata_crstate);
8df7a775 1997
1998 /*
1999 * To begin with, feed the characters one by one to the
2000 * protocol initialisation / selection function do_ssh_init().
2001 * When that returns 0, we're done with the initial greeting
2002 * exchange and can move on to packet discipline.
2003 */
2004 while (1) {
51470298 2005 int ret; /* need not be kept across crReturn */
8df7a775 2006 if (datalen == 0)
2007 crReturnV; /* more data please */
51470298 2008 ret = do_ssh_init(ssh, *data);
32874aea 2009 data++;
2010 datalen--;
8df7a775 2011 if (ret == 0)
2012 break;
2013 }
2014
2015 /*
2016 * We emerge from that loop when the initial negotiation is
2017 * over and we have selected an s_rdpkt function. Now pass
2018 * everything to s_rdpkt, and then pass the resulting packets
2019 * to the proper protocol handler.
2020 */
2021 if (datalen == 0)
2022 crReturnV;
2023 while (1) {
2024 while (datalen > 0) {
51470298 2025 if (ssh->s_rdpkt(ssh, &data, &datalen) == 0) {
2026 if (ssh->state == SSH_STATE_CLOSED) {
e14d0f19 2027 return;
2028 }
51470298 2029 ssh->protocol(ssh, NULL, 0, 1);
2030 if (ssh->state == SSH_STATE_CLOSED) {
8df7a775 2031 return;
2032 }
2033 }
2034 }
2035 crReturnV;
2036 }
2037 crFinishV;
2038}
2039
36f94d1f 2040static void ssh_do_close(Ssh ssh)
32874aea 2041{
36f94d1f 2042 int i;
2043 struct ssh_channel *c;
2044
51470298 2045 ssh->state = SSH_STATE_CLOSED;
2046 if (ssh->s) {
2047 sk_close(ssh->s);
2048 ssh->s = NULL;
f3ab576e 2049 }
36f94d1f 2050 /*
2051 * Now we must shut down any port and X forwardings going
2052 * through this connection.
2053 */
74a98066 2054 if (ssh->channels) {
2055 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
2056 switch (c->type) {
2057 case CHAN_X11:
2058 x11_close(c->u.x11.s);
2059 break;
2060 case CHAN_SOCKDATA:
2061 pfd_close(c->u.pfd.s);
2062 break;
2063 }
2064 del234(ssh->channels, c);
2065 if (ssh->version == 2)
2066 bufchain_clear(&c->v.v2.outbuffer);
2067 sfree(c);
36f94d1f 2068 }
36f94d1f 2069 }
2070}
2071
2072static int ssh_closing(Plug plug, char *error_msg, int error_code,
2073 int calling_back)
2074{
2075 Ssh ssh = (Ssh) plug;
2076 ssh_do_close(ssh);
7e78000d 2077 if (error_msg) {
32874aea 2078 /* A socket error has occurred. */
247308b5 2079 logevent(error_msg);
a8327734 2080 connection_fatal(ssh->frontend, error_msg);
7e78000d 2081 } else {
2082 /* Otherwise, the remote side closed the connection normally. */
8df7a775 2083 }
7e78000d 2084 return 0;
2085}
2086
32874aea 2087static int ssh_receive(Plug plug, int urgent, char *data, int len)
2088{
51470298 2089 Ssh ssh = (Ssh) plug;
d8baa528 2090 ssh_gotdata(ssh, (unsigned char *)data, len);
51470298 2091 if (ssh->state == SSH_STATE_CLOSED) {
36f94d1f 2092 ssh_do_close(ssh);
32874aea 2093 return 0;
3257deae 2094 }
fef97f43 2095 return 1;
374330e2 2096}
2097
5471d09a 2098static void ssh_sent(Plug plug, int bufsize)
2099{
51470298 2100 Ssh ssh = (Ssh) plug;
5471d09a 2101 /*
2102 * If the send backlog on the SSH socket itself clears, we
2103 * should unthrottle the whole world if it was throttled.
2104 */
2105 if (bufsize < SSH_MAX_BACKLOG)
51470298 2106 ssh_throttle_all(ssh, 0, bufsize);
5471d09a 2107}
2108
fb09bf1c 2109/*
8df7a775 2110 * Connect to specified host and port.
2111 * Returns an error message, or NULL on success.
6e1ebb76 2112 * Also places the canonical host name into `realhost'. It must be
2113 * freed by the caller.
8df7a775 2114 */
51470298 2115static char *connect_to_host(Ssh ssh, char *host, int port,
2116 char **realhost, int nodelay)
8df7a775 2117{
51470298 2118 static const struct plug_function_table fn_table = {
7e78000d 2119 ssh_closing,
5471d09a 2120 ssh_receive,
2121 ssh_sent,
2122 NULL
51470298 2123 };
7e78000d 2124
8df7a775 2125 SockAddr addr;
2126 char *err;
8df7a775 2127
3d88e64d 2128 ssh->savedhost = snewn(1 + strlen(host), char);
51470298 2129 if (!ssh->savedhost)
8df7a775 2130 fatalbox("Out of memory");
51470298 2131 strcpy(ssh->savedhost, host);
8df7a775 2132
2133 if (port < 0)
2134 port = 22; /* default ssh port */
51470298 2135 ssh->savedport = port;
8df7a775 2136
2137 /*
2138 * Try to find host.
2139 */
57356d63 2140 logeventf(ssh, "Looking up host \"%s\"", host);
e8fa8f62 2141 addr = name_lookup(host, port, realhost, &ssh->cfg);
70e5d0fd 2142 if ((err = sk_addr_error(addr)) != NULL)
8df7a775 2143 return err;
2144
8df7a775 2145 /*
2146 * Open socket.
2147 */
3ad9d396 2148 {
57356d63 2149 char addrbuf[100];
3ad9d396 2150 sk_getaddr(addr, addrbuf, 100);
57356d63 2151 logeventf(ssh, "Connecting to %s port %d", addrbuf, port);
3ad9d396 2152 }
51470298 2153 ssh->fn = &fn_table;
e8fa8f62 2154 ssh->s = new_connection(addr, *realhost, port,
2155 0, 1, nodelay, (Plug) ssh, &ssh->cfg);
70e5d0fd 2156 if ((err = sk_socket_error(ssh->s)) != NULL) {
51470298 2157 ssh->s = NULL;
8df7a775 2158 return err;
67c4ba2e 2159 }
8df7a775 2160
8df7a775 2161 return NULL;
2162}
2163
2164/*
5471d09a 2165 * Throttle or unthrottle the SSH connection.
2166 */
51470298 2167static void ssh1_throttle(Ssh ssh, int adjust)
5471d09a 2168{
51470298 2169 int old_count = ssh->v1_throttle_count;
2170 ssh->v1_throttle_count += adjust;
2171 assert(ssh->v1_throttle_count >= 0);
2172 if (ssh->v1_throttle_count && !old_count) {
2173 sk_set_frozen(ssh->s, 1);
2174 } else if (!ssh->v1_throttle_count && old_count) {
2175 sk_set_frozen(ssh->s, 0);
5471d09a 2176 }
2177}
2178
2179/*
2180 * Throttle or unthrottle _all_ local data streams (for when sends
2181 * on the SSH connection itself back up).
2182 */
51470298 2183static void ssh_throttle_all(Ssh ssh, int enable, int bufsize)
5471d09a 2184{
2185 int i;
2186 struct ssh_channel *c;
2187
51470298 2188 if (enable == ssh->throttled_all)
5471d09a 2189 return;
51470298 2190 ssh->throttled_all = enable;
2191 ssh->overall_bufsize = bufsize;
2192 if (!ssh->channels)
5471d09a 2193 return;
51470298 2194 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
5471d09a 2195 switch (c->type) {
2196 case CHAN_MAINSESSION:
2197 /*
2198 * This is treated separately, outside the switch.
2199 */
2200 break;
2201 case CHAN_X11:
2202 x11_override_throttle(c->u.x11.s, enable);
2203 break;
2204 case CHAN_AGENT:
2205 /* Agent channels require no buffer management. */
2206 break;
2207 case CHAN_SOCKDATA:
36f94d1f 2208 pfd_override_throttle(c->u.pfd.s, enable);
5471d09a 2209 break;
2210 }
2211 }
2212}
2213
2214/*
51470298 2215 * Username and password input, abstracted off into routines
2216 * reusable in several places - even between SSH1 and SSH2.
0405e71f 2217 */
0405e71f 2218
2219/* Set up a username or password input loop on a given buffer. */
ae9ae89f 2220static void setup_userpass_input(Ssh ssh, char *buffer, int buflen, int echo)
0405e71f 2221{
51470298 2222 ssh->userpass_input_buffer = buffer;
2223 ssh->userpass_input_buflen = buflen;
2224 ssh->userpass_input_bufpos = 0;
2225 ssh->userpass_input_echo = echo;
0405e71f 2226}
2227
2228/*
2229 * Process some terminal data in the course of username/password
2230 * input. Returns >0 for success (line of input returned in
2231 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2232 * for inconclusive (keep waiting for more input please).
2233 */
ae9ae89f 2234static int process_userpass_input(Ssh ssh, unsigned char *in, int inlen)
0405e71f 2235{
2236 char c;
2237
2238 while (inlen--) {
2239 switch (c = *in++) {
2240 case 10:
2241 case 13:
51470298 2242 ssh->userpass_input_buffer[ssh->userpass_input_bufpos] = 0;
2243 ssh->userpass_input_buffer[ssh->userpass_input_buflen-1] = 0;
0405e71f 2244 return +1;
2245 break;
2246 case 8:
2247 case 127:
51470298 2248 if (ssh->userpass_input_bufpos > 0) {
2249 if (ssh->userpass_input_echo)
2250 c_write_str(ssh, "\b \b");
2251 ssh->userpass_input_bufpos--;
0405e71f 2252 }
2253 break;
2254 case 21:
2255 case 27:
51470298 2256 while (ssh->userpass_input_bufpos > 0) {
2257 if (ssh->userpass_input_echo)
2258 c_write_str(ssh, "\b \b");
2259 ssh->userpass_input_bufpos--;
0405e71f 2260 }
2261 break;
2262 case 3:
2263 case 4:
2264 return -1;
2265 break;
2266 default:
4692a14a 2267 /*
2268 * This simplistic check for printability is disabled
2269 * when we're doing password input, because some people
2270 * have control characters in their passwords.o
2271 */
2272 if ((!ssh->userpass_input_echo ||
2273 (c >= ' ' && c <= '~') ||
0405e71f 2274 ((unsigned char) c >= 160))
51470298 2275 && ssh->userpass_input_bufpos < ssh->userpass_input_buflen-1) {
2276 ssh->userpass_input_buffer[ssh->userpass_input_bufpos++] = c;
2277 if (ssh->userpass_input_echo)
2278 c_write(ssh, &c, 1);
0405e71f 2279 }
2280 break;
2281 }
2282 }
2283 return 0;
2284}
2285
2286/*
fb09bf1c 2287 * Handle the key exchange and user authentication phases.
2288 */
51470298 2289static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
fb09bf1c 2290{
2d466ffd 2291 int i, j;
374330e2 2292 unsigned char cookie[8];
2293 struct RSAKey servkey, hostkey;
2294 struct MD5Context md5c;
51470298 2295 struct do_ssh1_login_state {
2296 int len;
2297 unsigned char *rsabuf, *keystr1, *keystr2;
2298 unsigned long supported_ciphers_mask, supported_auths_mask;
2299 int tried_publickey, tried_agent;
2300 int tis_auth_refused, ccard_auth_refused;
2301 unsigned char session_id[16];
2302 int cipher_type;
2303 char username[100];
2304 void *publickey_blob;
2305 int publickey_bloblen;
2306 char password[100];
2307 char prompt[200];
2308 int pos;
2309 char c;
2310 int pwpkt_type;
2311 unsigned char request[5], *response, *p;
2312 int responselen;
2313 int keyi, nkeys;
2314 int authed;
2315 struct RSAKey key;
2316 Bignum challenge;
2317 char *commentp;
2318 int commentlen;
2319 };
2320 crState(do_ssh1_login_state);
2321
2322 crBegin(ssh->do_ssh1_login_crstate);
374330e2 2323
32874aea 2324 if (!ispkt)
2325 crWaitUntil(ispkt);
374330e2 2326
51470298 2327 if (ssh->pktin.type != SSH1_SMSG_PUBLIC_KEY) {
6b5cf8b4 2328 bombout(("Public key packet not received"));
7ffdbc1a 2329 crStop(0);
8d5de777 2330 }
374330e2 2331
c5e9c988 2332 logevent("Received public keys");
374330e2 2333
51470298 2334 memcpy(cookie, ssh->pktin.body, 8);
374330e2 2335
51470298 2336 i = makekey(ssh->pktin.body + 8, &servkey, &s->keystr1, 0);
2337 j = makekey(ssh->pktin.body + 8 + i, &hostkey, &s->keystr2, 0);
374330e2 2338
c5e9c988 2339 /*
1c2a93c4 2340 * Log the host key fingerprint.
c5e9c988 2341 */
c5e9c988 2342 {
2343 char logmsg[80];
1c2a93c4 2344 logevent("Host key fingerprint is:");
c5e9c988 2345 strcpy(logmsg, " ");
32874aea 2346 hostkey.comment = NULL;
2347 rsa_fingerprint(logmsg + strlen(logmsg),
2348 sizeof(logmsg) - strlen(logmsg), &hostkey);
c5e9c988 2349 logevent(logmsg);
2350 }
2351
51470298 2352 ssh->v1_remote_protoflags = GET_32BIT(ssh->pktin.body + 8 + i + j);
2353 s->supported_ciphers_mask = GET_32BIT(ssh->pktin.body + 12 + i + j);
2354 s->supported_auths_mask = GET_32BIT(ssh->pktin.body + 16 + i + j);
bea1ef5f 2355
51470298 2356 ssh->v1_local_protoflags =
2357 ssh->v1_remote_protoflags & SSH1_PROTOFLAGS_SUPPORTED;
2358 ssh->v1_local_protoflags |= SSH1_PROTOFLAG_SCREEN_NUMBER;
b96dc54c 2359
c5e9c988 2360 MD5Init(&md5c);
51470298 2361 MD5Update(&md5c, s->keystr2, hostkey.bytes);
2362 MD5Update(&md5c, s->keystr1, servkey.bytes);
2363 MD5Update(&md5c, ssh->pktin.body, 8);
2364 MD5Final(s->session_id, &md5c);
374330e2 2365
32874aea 2366 for (i = 0; i < 32; i++)
51470298 2367 ssh->session_key[i] = random_byte();
374330e2 2368
51470298 2369 s->len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
374330e2 2370
3d88e64d 2371 s->rsabuf = snewn(s->len, unsigned char);
51470298 2372 if (!s->rsabuf)
374330e2 2373 fatalbox("Out of memory");
2374
89ee5268 2375 /*
2376 * Verify the host key.
2377 */
2378 {
32874aea 2379 /*
2380 * First format the key into a string.
2381 */
2382 int len = rsastr_len(&hostkey);
2383 char fingerprint[100];
3d88e64d 2384 char *keystr = snewn(len, char);
32874aea 2385 if (!keystr)
2386 fatalbox("Out of memory");
2387 rsastr_fmt(keystr, &hostkey);
2388 rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
a8327734 2389 verify_ssh_host_key(ssh->frontend,
2390 ssh->savedhost, ssh->savedport, "rsa", keystr,
32874aea 2391 fingerprint);
2392 sfree(keystr);
2393 }
2394
2395 for (i = 0; i < 32; i++) {
51470298 2396 s->rsabuf[i] = ssh->session_key[i];
374330e2 2397 if (i < 16)
51470298 2398 s->rsabuf[i] ^= s->session_id[i];
374330e2 2399 }
2400
2401 if (hostkey.bytes > servkey.bytes) {
51470298 2402 rsaencrypt(s->rsabuf, 32, &servkey);
2403 rsaencrypt(s->rsabuf, servkey.bytes, &hostkey);
374330e2 2404 } else {
51470298 2405 rsaencrypt(s->rsabuf, 32, &hostkey);
2406 rsaencrypt(s->rsabuf, hostkey.bytes, &servkey);
374330e2 2407 }
2408
c5e9c988 2409 logevent("Encrypted session key");
2410
ca20bfcf 2411 {
2412 int cipher_chosen = 0, warn = 0;
2413 char *cipher_string = NULL;
51470298 2414 int i;
ca20bfcf 2415 for (i = 0; !cipher_chosen && i < CIPHER_MAX; i++) {
86916870 2416 int next_cipher = ssh->cfg.ssh_cipherlist[i];
ca20bfcf 2417 if (next_cipher == CIPHER_WARN) {
2418 /* If/when we choose a cipher, warn about it */
2419 warn = 1;
2420 } else if (next_cipher == CIPHER_AES) {
2421 /* XXX Probably don't need to mention this. */
2422 logevent("AES not supported in SSH1, skipping");
2423 } else {
2424 switch (next_cipher) {
51470298 2425 case CIPHER_3DES: s->cipher_type = SSH_CIPHER_3DES;
ca20bfcf 2426 cipher_string = "3DES"; break;
51470298 2427 case CIPHER_BLOWFISH: s->cipher_type = SSH_CIPHER_BLOWFISH;
ca20bfcf 2428 cipher_string = "Blowfish"; break;
51470298 2429 case CIPHER_DES: s->cipher_type = SSH_CIPHER_DES;
ca20bfcf 2430 cipher_string = "single-DES"; break;
2431 }
51470298 2432 if (s->supported_ciphers_mask & (1 << s->cipher_type))
ca20bfcf 2433 cipher_chosen = 1;
2434 }
2435 }
2436 if (!cipher_chosen) {
51470298 2437 if ((s->supported_ciphers_mask & (1 << SSH_CIPHER_3DES)) == 0)
6b5cf8b4 2438 bombout(("Server violates SSH 1 protocol by not "
ca20bfcf 2439 "supporting 3DES encryption"));
2440 else
2441 /* shouldn't happen */
6b5cf8b4 2442 bombout(("No supported ciphers found"));
7ffdbc1a 2443 crStop(0);
a99a05c0 2444 }
ca20bfcf 2445
2446 /* Warn about chosen cipher if necessary. */
2447 if (warn)
a8327734 2448 askcipher(ssh->frontend, cipher_string, 0);
bea1ef5f 2449 }
ca20bfcf 2450
51470298 2451 switch (s->cipher_type) {
32874aea 2452 case SSH_CIPHER_3DES:
2453 logevent("Using 3DES encryption");
2454 break;
2455 case SSH_CIPHER_DES:
2456 logevent("Using single-DES encryption");
2457 break;
2458 case SSH_CIPHER_BLOWFISH:
2459 logevent("Using Blowfish encryption");
2460 break;
c5e9c988 2461 }
bea1ef5f 2462
51470298 2463 send_packet(ssh, SSH1_CMSG_SESSION_KEY,
2464 PKT_CHAR, s->cipher_type,
32874aea 2465 PKT_DATA, cookie, 8,
51470298 2466 PKT_CHAR, (s->len * 8) >> 8, PKT_CHAR, (s->len * 8) & 0xFF,
2467 PKT_DATA, s->rsabuf, s->len,
2468 PKT_INT, ssh->v1_local_protoflags, PKT_END);
fb09bf1c 2469
c5e9c988 2470 logevent("Trying to enable encryption...");
374330e2 2471
51470298 2472 sfree(s->rsabuf);
374330e2 2473
51470298 2474 ssh->cipher = (s->cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
2475 s->cipher_type == SSH_CIPHER_DES ? &ssh_des :
2476 &ssh_3des);
371e569c 2477 ssh->v1_cipher_ctx = ssh->cipher->make_context();
2478 ssh->cipher->sesskey(ssh->v1_cipher_ctx, ssh->session_key);
57356d63 2479 logeventf(ssh, "Initialised %s encryption", ssh->cipher->text_name);
374330e2 2480
0183b242 2481 ssh->crcda_ctx = crcda_make_context();
2482 logevent("Installing CRC compensation attack detector");
2483
fb09bf1c 2484 crWaitUntil(ispkt);
374330e2 2485
51470298 2486 if (ssh->pktin.type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 2487 bombout(("Encryption not successfully enabled"));
7ffdbc1a 2488 crStop(0);
8d5de777 2489 }
374330e2 2490
c5e9c988 2491 logevent("Successfully started encryption");
2492
374330e2 2493 fflush(stdout);
2494 {
86916870 2495 if ((flags & FLAG_INTERACTIVE) && !*ssh->cfg.username) {
c0a81592 2496 if (ssh_get_line && !ssh_getline_pw_only) {
32874aea 2497 if (!ssh_get_line("login as: ",
51470298 2498 s->username, sizeof(s->username), FALSE)) {
32874aea 2499 /*
2500 * get_line failed to get a username.
2501 * Terminate.
2502 */
2503 logevent("No username provided. Abandoning session.");
3bb2f322 2504 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 2505 crStop(1);
32874aea 2506 }
2507 } else {
51470298 2508 int ret; /* need not be kept over crReturn */
2509 c_write_str(ssh, "login as: ");
2510 ssh->send_ok = 1;
0405e71f 2511
51470298 2512 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
0405e71f 2513 do {
32874aea 2514 crWaitUntil(!ispkt);
51470298 2515 ret = process_userpass_input(ssh, in, inlen);
0405e71f 2516 } while (ret == 0);
2517 if (ret < 0)
2518 cleanup_exit(0);
51470298 2519 c_write_str(ssh, "\r\n");
32874aea 2520 }
2521 } else {
86916870 2522 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
51470298 2523 s->username[sizeof(s->username)-1] = '\0';
374330e2 2524 }
fb09bf1c 2525
51470298 2526 send_packet(ssh, SSH1_CMSG_USER, PKT_STR, s->username, PKT_END);
c5e9c988 2527 {
51470298 2528 char userlog[22 + sizeof(s->username)];
2529 sprintf(userlog, "Sent username \"%s\"", s->username);
c5e9c988 2530 logevent(userlog);
32874aea 2531 if (flags & FLAG_INTERACTIVE &&
2532 (!((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)))) {
3c8e959b 2533 strcat(userlog, "\r\n");
51470298 2534 c_write_str(ssh, userlog);
3c8e959b 2535 }
c5e9c988 2536 }
374330e2 2537 }
2538
fb09bf1c 2539 crWaitUntil(ispkt);
374330e2 2540
51470298 2541 if ((ssh->remote_bugs & BUG_CHOKES_ON_RSA)) {
0df73905 2542 /* We must not attempt PK auth. Pretend we've already tried it. */
51470298 2543 s->tried_publickey = s->tried_agent = 1;
0df73905 2544 } else {
51470298 2545 s->tried_publickey = s->tried_agent = 0;
0df73905 2546 }
51470298 2547 s->tis_auth_refused = s->ccard_auth_refused = 0;
86916870 2548 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
9a30e26b 2549 if (!filename_is_null(ssh->cfg.keyfile)) {
2550 if (!rsakey_pubblob(&ssh->cfg.keyfile,
51470298 2551 &s->publickey_blob, &s->publickey_bloblen))
2552 s->publickey_blob = NULL;
396778f1 2553 } else
51470298 2554 s->publickey_blob = NULL;
7cca0d81 2555
51470298 2556 while (ssh->pktin.type == SSH1_SMSG_FAILURE) {
2557 s->pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
614a20a0 2558
51470298 2559 if (agent_exists() && !s->tried_agent) {
32874aea 2560 /*
2561 * Attempt RSA authentication using Pageant.
2562 */
32874aea 2563 void *r;
2564
51470298 2565 s->authed = FALSE;
2566 s->tried_agent = 1;
32874aea 2567 logevent("Pageant is running. Requesting keys.");
2568
2569 /* Request the keys held by the agent. */
51470298 2570 PUT_32BIT(s->request, 1);
2571 s->request[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES;
2572 agent_query(s->request, 5, &r, &s->responselen);
2573 s->response = (unsigned char *) r;
2574 if (s->response && s->responselen >= 5 &&
2575 s->response[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER) {
2576 s->p = s->response + 5;
2577 s->nkeys = GET_32BIT(s->p);
2578 s->p += 4;
32874aea 2579 {
2580 char buf[64];
51470298 2581 sprintf(buf, "Pageant has %d SSH1 keys", s->nkeys);
32874aea 2582 logevent(buf);
2583 }
51470298 2584 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
32874aea 2585 {
2586 char buf[64];
51470298 2587 sprintf(buf, "Trying Pageant key #%d", s->keyi);
32874aea 2588 logevent(buf);
2589 }
51470298 2590 if (s->publickey_blob &&
2591 !memcmp(s->p, s->publickey_blob,
2592 s->publickey_bloblen)) {
396778f1 2593 logevent("This key matches configured key file");
51470298 2594 s->tried_publickey = 1;
396778f1 2595 }
51470298 2596 s->p += 4;
2597 s->p += ssh1_read_bignum(s->p, &s->key.exponent);
2598 s->p += ssh1_read_bignum(s->p, &s->key.modulus);
2599 s->commentlen = GET_32BIT(s->p);
2600 s->p += 4;
d8baa528 2601 s->commentp = (char *)s->p;
51470298 2602 s->p += s->commentlen;
2603 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
2604 PKT_BIGNUM, s->key.modulus, PKT_END);
32874aea 2605 crWaitUntil(ispkt);
51470298 2606 if (ssh->pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
32874aea 2607 logevent("Key refused");
2608 continue;
2609 }
2610 logevent("Received RSA challenge");
51470298 2611 ssh1_read_bignum(ssh->pktin.body, &s->challenge);
32874aea 2612 {
2613 char *agentreq, *q, *ret;
2d466ffd 2614 void *vret;
32874aea 2615 int len, retlen;
2616 len = 1 + 4; /* message type, bit count */
51470298 2617 len += ssh1_bignum_length(s->key.exponent);
2618 len += ssh1_bignum_length(s->key.modulus);
2619 len += ssh1_bignum_length(s->challenge);
32874aea 2620 len += 16; /* session id */
2621 len += 4; /* response format */
3d88e64d 2622 agentreq = snewn(4 + len, char);
32874aea 2623 PUT_32BIT(agentreq, len);
2624 q = agentreq + 4;
2625 *q++ = SSH1_AGENTC_RSA_CHALLENGE;
51470298 2626 PUT_32BIT(q, bignum_bitcount(s->key.modulus));
32874aea 2627 q += 4;
51470298 2628 q += ssh1_write_bignum(q, s->key.exponent);
2629 q += ssh1_write_bignum(q, s->key.modulus);
2630 q += ssh1_write_bignum(q, s->challenge);
2631 memcpy(q, s->session_id, 16);
32874aea 2632 q += 16;
2633 PUT_32BIT(q, 1); /* response format */
2d466ffd 2634 agent_query(agentreq, len + 4, &vret, &retlen);
2635 ret = vret;
32874aea 2636 sfree(agentreq);
2637 if (ret) {
2638 if (ret[4] == SSH1_AGENT_RSA_RESPONSE) {
2639 logevent("Sending Pageant's response");
51470298 2640 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
32874aea 2641 PKT_DATA, ret + 5, 16,
2642 PKT_END);
2643 sfree(ret);
2644 crWaitUntil(ispkt);
51470298 2645 if (ssh->pktin.type == SSH1_SMSG_SUCCESS) {
32874aea 2646 logevent
2647 ("Pageant's response accepted");
2648 if (flags & FLAG_VERBOSE) {
51470298 2649 c_write_str(ssh, "Authenticated using"
2650 " RSA key \"");
2651 c_write(ssh, s->commentp,
2652 s->commentlen);
2653 c_write_str(ssh, "\" from agent\r\n");
32874aea 2654 }
51470298 2655 s->authed = TRUE;
32874aea 2656 } else
2657 logevent
2658 ("Pageant's response not accepted");
2659 } else {
2660 logevent
2661 ("Pageant failed to answer challenge");
2662 sfree(ret);
2663 }
2664 } else {
2665 logevent("No reply received from Pageant");
2666 }
2667 }
51470298 2668 freebn(s->key.exponent);
2669 freebn(s->key.modulus);
2670 freebn(s->challenge);
2671 if (s->authed)
32874aea 2672 break;
2673 }
2674 }
51470298 2675 if (s->authed)
32874aea 2676 break;
2677 }
9a30e26b 2678 if (!filename_is_null(ssh->cfg.keyfile) && !s->tried_publickey)
51470298 2679 s->pwpkt_type = SSH1_CMSG_AUTH_RSA;
32874aea 2680
86916870 2681 if (ssh->cfg.try_tis_auth &&
51470298 2682 (s->supported_auths_mask & (1 << SSH1_AUTH_TIS)) &&
2683 !s->tis_auth_refused) {
2684 s->pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
32874aea 2685 logevent("Requested TIS authentication");
51470298 2686 send_packet(ssh, SSH1_CMSG_AUTH_TIS, PKT_END);
32874aea 2687 crWaitUntil(ispkt);
51470298 2688 if (ssh->pktin.type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
32874aea 2689 logevent("TIS authentication declined");
2690 if (flags & FLAG_INTERACTIVE)
51470298 2691 c_write_str(ssh, "TIS authentication refused.\r\n");
2692 s->tis_auth_refused = 1;
614a20a0 2693 continue;
32874aea 2694 } else {
51470298 2695 int challengelen = GET_32BIT(ssh->pktin.body);
32874aea 2696 logevent("Received TIS challenge");
51470298 2697 if (challengelen > sizeof(s->prompt) - 1)
2698 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
2699 memcpy(s->prompt, ssh->pktin.body + 4, challengelen);
614a20a0 2700 /* Prompt heuristic comes from OpenSSH */
51470298 2701 strncpy(s->prompt + challengelen,
2702 memchr(s->prompt, '\n', challengelen) ?
614a20a0 2703 "": "\r\nResponse: ",
51470298 2704 (sizeof s->prompt) - challengelen);
2705 s->prompt[(sizeof s->prompt) - 1] = '\0';
32874aea 2706 }
2707 }
86916870 2708 if (ssh->cfg.try_tis_auth &&
51470298 2709 (s->supported_auths_mask & (1 << SSH1_AUTH_CCARD)) &&
2710 !s->ccard_auth_refused) {
2711 s->pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
32874aea 2712 logevent("Requested CryptoCard authentication");
51470298 2713 send_packet(ssh, SSH1_CMSG_AUTH_CCARD, PKT_END);
32874aea 2714 crWaitUntil(ispkt);
51470298 2715 if (ssh->pktin.type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
32874aea 2716 logevent("CryptoCard authentication declined");
51470298 2717 c_write_str(ssh, "CryptoCard authentication refused.\r\n");
2718 s->ccard_auth_refused = 1;
614a20a0 2719 continue;
32874aea 2720 } else {
51470298 2721 int challengelen = GET_32BIT(ssh->pktin.body);
32874aea 2722 logevent("Received CryptoCard challenge");
51470298 2723 if (challengelen > sizeof(s->prompt) - 1)
2724 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
2725 memcpy(s->prompt, ssh->pktin.body + 4, challengelen);
2726 strncpy(s->prompt + challengelen,
2727 memchr(s->prompt, '\n', challengelen) ?
614a20a0 2728 "" : "\r\nResponse: ",
51470298 2729 sizeof(s->prompt) - challengelen);
2730 s->prompt[sizeof(s->prompt) - 1] = '\0';
32874aea 2731 }
2732 }
51470298 2733 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
2734 sprintf(s->prompt, "%.90s@%.90s's password: ",
2735 s->username, ssh->savedhost);
32874aea 2736 }
51470298 2737 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
32874aea 2738 char *comment = NULL;
231ee168 2739 int type;
2740 char msgbuf[256];
32874aea 2741 if (flags & FLAG_VERBOSE)
51470298 2742 c_write_str(ssh, "Trying public key authentication.\r\n");
6c6d9ed9 2743 logeventf(ssh, "Trying public key \"%s\"",
2744 filename_to_str(&ssh->cfg.keyfile));
9a30e26b 2745 type = key_type(&ssh->cfg.keyfile);
231ee168 2746 if (type != SSH_KEYTYPE_SSH1) {
2747 sprintf(msgbuf, "Key is of wrong type (%s)",
2748 key_type_to_str(type));
2749 logevent(msgbuf);
51470298 2750 c_write_str(ssh, msgbuf);
2751 c_write_str(ssh, "\r\n");
2752 s->tried_publickey = 1;
231ee168 2753 continue;
2754 }
9a30e26b 2755 if (!rsakey_encrypted(&ssh->cfg.keyfile, &comment)) {
32874aea 2756 if (flags & FLAG_VERBOSE)
51470298 2757 c_write_str(ssh, "No passphrase required.\r\n");
32874aea 2758 goto tryauth;
2759 }
51470298 2760 sprintf(s->prompt, "Passphrase for key \"%.100s\": ", comment);
32874aea 2761 sfree(comment);
2762 }
a52f067e 2763
614a20a0 2764 /*
2765 * Show password prompt, having first obtained it via a TIS
2766 * or CryptoCard exchange if we're doing TIS or CryptoCard
2767 * authentication.
2768 */
fa17a66e 2769 if (ssh_get_line) {
51470298 2770 if (!ssh_get_line(s->prompt, s->password,
2771 sizeof(s->password), TRUE)) {
32874aea 2772 /*
2773 * get_line failed to get a password (for example
2774 * because one was supplied on the command line
2775 * which has already failed to work). Terminate.
2776 */
51470298 2777 send_packet(ssh, SSH1_MSG_DISCONNECT,
2bc6a386 2778 PKT_STR, "No more passwords available to try",
2779 PKT_END);
247308b5 2780 logevent("Unable to authenticate");
a8327734 2781 connection_fatal(ssh->frontend, "Unable to authenticate");
3bb2f322 2782 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 2783 crStop(1);
32874aea 2784 }
fb09bf1c 2785 } else {
614a20a0 2786 /* Prompt may have come from server. We've munged it a bit, so
2787 * we know it to be zero-terminated at least once. */
51470298 2788 int ret; /* need not be saved over crReturn */
2789 c_write_untrusted(ssh, s->prompt, strlen(s->prompt));
2790 s->pos = 0;
0405e71f 2791
51470298 2792 setup_userpass_input(ssh, s->password, sizeof(s->password), 0);
0405e71f 2793 do {
32874aea 2794 crWaitUntil(!ispkt);
51470298 2795 ret = process_userpass_input(ssh, in, inlen);
0405e71f 2796 } while (ret == 0);
2797 if (ret < 0)
2798 cleanup_exit(0);
51470298 2799 c_write_str(ssh, "\r\n");
32874aea 2800 }
2801
2802 tryauth:
51470298 2803 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
32874aea 2804 /*
2805 * Try public key authentication with the specified
2806 * key file.
2807 */
51470298 2808 s->tried_publickey = 1;
2809
2810 {
9a30e26b 2811 int ret = loadrsakey(&ssh->cfg.keyfile, &s->key, s->password);
51470298 2812 if (ret == 0) {
2813 c_write_str(ssh, "Couldn't load private key from ");
9fab77dc 2814 c_write_str(ssh, filename_to_str(&ssh->cfg.keyfile));
51470298 2815 c_write_str(ssh, ".\r\n");
2816 continue; /* go and try password */
2817 }
2818 if (ret == -1) {
2819 c_write_str(ssh, "Wrong passphrase.\r\n");
2820 s->tried_publickey = 0;
2821 continue; /* try again */
2822 }
32874aea 2823 }
2824
2825 /*
2826 * Send a public key attempt.
2827 */
51470298 2828 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
2829 PKT_BIGNUM, s->key.modulus, PKT_END);
32874aea 2830
2831 crWaitUntil(ispkt);
51470298 2832 if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
2833 c_write_str(ssh, "Server refused our public key.\r\n");
32874aea 2834 continue; /* go and try password */
2835 }
51470298 2836 if (ssh->pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
6b5cf8b4 2837 bombout(("Bizarre response to offer of public key"));
7ffdbc1a 2838 crStop(0);
32874aea 2839 }
32874aea 2840
51470298 2841 {
2842 int i;
2843 unsigned char buffer[32];
2844 Bignum challenge, response;
2845
2846 ssh1_read_bignum(ssh->pktin.body, &challenge);
2847 response = rsadecrypt(challenge, &s->key);
2848 freebn(s->key.private_exponent);/* burn the evidence */
32874aea 2849
51470298 2850 for (i = 0; i < 32; i++) {
2851 buffer[i] = bignum_byte(response, 31 - i);
2852 }
2853
2854 MD5Init(&md5c);
2855 MD5Update(&md5c, buffer, 32);
2856 MD5Update(&md5c, s->session_id, 16);
2857 MD5Final(buffer, &md5c);
32874aea 2858
51470298 2859 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
2860 PKT_DATA, buffer, 16, PKT_END);
2861
2862 freebn(challenge);
2863 freebn(response);
2864 }
32874aea 2865
2866 crWaitUntil(ispkt);
51470298 2867 if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
32874aea 2868 if (flags & FLAG_VERBOSE)
51470298 2869 c_write_str(ssh, "Failed to authenticate with"
2870 " our public key.\r\n");
32874aea 2871 continue; /* go and try password */
51470298 2872 } else if (ssh->pktin.type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 2873 bombout(("Bizarre response to RSA authentication response"));
7ffdbc1a 2874 crStop(0);
32874aea 2875 }
2876
2877 break; /* we're through! */
2878 } else {
51470298 2879 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
32874aea 2880 /*
2881 * Defence against traffic analysis: we send a
2882 * whole bunch of packets containing strings of
2883 * different lengths. One of these strings is the
2884 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
2885 * The others are all random data in
2886 * SSH1_MSG_IGNORE packets. This way a passive
2887 * listener can't tell which is the password, and
2888 * hence can't deduce the password length.
2889 *
2890 * Anybody with a password length greater than 16
2891 * bytes is going to have enough entropy in their
2892 * password that a listener won't find it _that_
2893 * much help to know how long it is. So what we'll
2894 * do is:
2895 *
2896 * - if password length < 16, we send 15 packets
2897 * containing string lengths 1 through 15
2898 *
2899 * - otherwise, we let N be the nearest multiple
2900 * of 8 below the password length, and send 8
2901 * packets containing string lengths N through
2902 * N+7. This won't obscure the order of
2903 * magnitude of the password length, but it will
2904 * introduce a bit of extra uncertainty.
2905 *
2906 * A few servers (the old 1.2.18 through 1.2.22)
2907 * can't deal with SSH1_MSG_IGNORE. For these
2908 * servers, we need an alternative defence. We make
2909 * use of the fact that the password is interpreted
2910 * as a C string: so we can append a NUL, then some
2911 * random data.
bd358db1 2912 *
2913 * One server (a Cisco one) can deal with neither
2914 * SSH1_MSG_IGNORE _nor_ a padded password string.
2915 * For this server we are left with no defences
2916 * against password length sniffing.
32874aea 2917 */
51470298 2918 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE)) {
b17c8428 2919 /*
2920 * The server can deal with SSH1_MSG_IGNORE, so
2921 * we can use the primary defence.
2922 */
32874aea 2923 int bottom, top, pwlen, i;
2924 char *randomstr;
2925
51470298 2926 pwlen = strlen(s->password);
32874aea 2927 if (pwlen < 16) {
2928 bottom = 0; /* zero length passwords are OK! :-) */
2929 top = 15;
2930 } else {
2931 bottom = pwlen & ~7;
2932 top = bottom + 7;
2933 }
2934
2935 assert(pwlen >= bottom && pwlen <= top);
2936
3d88e64d 2937 randomstr = snewn(top + 1, char);
32874aea 2938
2939 for (i = bottom; i <= top; i++) {
2940 if (i == pwlen)
51470298 2941 defer_packet(ssh, s->pwpkt_type,
2942 PKT_STR, s->password, PKT_END);
32874aea 2943 else {
2944 for (j = 0; j < i; j++) {
2945 do {
2946 randomstr[j] = random_byte();
2947 } while (randomstr[j] == '\0');
2948 }
2949 randomstr[i] = '\0';
51470298 2950 defer_packet(ssh, SSH1_MSG_IGNORE,
32874aea 2951 PKT_STR, randomstr, PKT_END);
2952 }
2953 }
bd358db1 2954 logevent("Sending password with camouflage packets");
51470298 2955 ssh_pkt_defersend(ssh);
bd358db1 2956 }
51470298 2957 else if (!(ssh->remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
b17c8428 2958 /*
2959 * The server can't deal with SSH1_MSG_IGNORE
2960 * but can deal with padded passwords, so we
2961 * can use the secondary defence.
2962 */
bd358db1 2963 char string[64];
51470298 2964 char *ss;
bd358db1 2965 int len;
2966
51470298 2967 len = strlen(s->password);
bd358db1 2968 if (len < sizeof(string)) {
51470298 2969 ss = string;
2970 strcpy(string, s->password);
bd358db1 2971 len++; /* cover the zero byte */
2972 while (len < sizeof(string)) {
2973 string[len++] = (char) random_byte();
2974 }
2975 } else {
51470298 2976 ss = s->password;
bd358db1 2977 }
2978 logevent("Sending length-padded password");
51470298 2979 send_packet(ssh, s->pwpkt_type, PKT_INT, len,
2980 PKT_DATA, ss, len, PKT_END);
bd358db1 2981 } else {
2982 /*
2983 * The server has _both_
2984 * BUG_CHOKES_ON_SSH1_IGNORE and
2985 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
2986 * therefore nothing we can do.
2987 */
2988 int len;
51470298 2989 len = strlen(s->password);
bd358db1 2990 logevent("Sending unpadded password");
51470298 2991 send_packet(ssh, s->pwpkt_type, PKT_INT, len,
2992 PKT_DATA, s->password, len, PKT_END);
32874aea 2993 }
2994 } else {
51470298 2995 send_packet(ssh, s->pwpkt_type, PKT_STR, s->password, PKT_END);
32874aea 2996 }
2997 }
c5e9c988 2998 logevent("Sent password");
51470298 2999 memset(s->password, 0, strlen(s->password));
fb09bf1c 3000 crWaitUntil(ispkt);
51470298 3001 if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
32874aea 3002 if (flags & FLAG_VERBOSE)
51470298 3003 c_write_str(ssh, "Access denied\r\n");
c5e9c988 3004 logevent("Authentication refused");
51470298 3005 } else if (ssh->pktin.type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 3006 bombout(("Strange packet received, type %d", ssh->pktin.type));
7ffdbc1a 3007 crStop(0);
374330e2 3008 }
3009 }
3010
c5e9c988 3011 logevent("Authentication successful");
3012
fb09bf1c 3013 crFinish(1);
3014}
3015
32874aea 3016void sshfwd_close(struct ssh_channel *c)
3017{
51470298 3018 Ssh ssh = c->ssh;
3019
36f94d1f 3020 if (ssh->state != SSH_STATE_SESSION) {
3021 assert(ssh->state == SSH_STATE_CLOSED);
3022 return;
3023 }
3024
80e48603 3025 if (c && !c->closes) {
4ed34d25 3026 /*
3027 * If the channel's remoteid is -1, we have sent
3028 * CHANNEL_OPEN for this channel, but it hasn't even been
3029 * acknowledged by the server. So we must set a close flag
3030 * on it now, and then when the server acks the channel
3031 * open, we can close it then.
3032 */
36cac739 3033 if (((int)c->remoteid) != -1) {
51470298 3034 if (ssh->version == 1) {
3035 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid,
4ed34d25 3036 PKT_END);
3037 } else {
51470298 3038 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_CLOSE);
3039 ssh2_pkt_adduint32(ssh, c->remoteid);
3040 ssh2_pkt_send(ssh);
4ed34d25 3041 }
32874aea 3042 }
0357890f 3043 c->closes = 1; /* sent MSG_CLOSE */
32874aea 3044 if (c->type == CHAN_X11) {
3045 c->u.x11.s = NULL;
d74d141c 3046 logevent("Forwarded X11 connection terminated");
4ed34d25 3047 } else if (c->type == CHAN_SOCKDATA ||
3048 c->type == CHAN_SOCKDATA_DORMANT) {
d74d141c 3049 c->u.pfd.s = NULL;
3050 logevent("Forwarded port closed");
32874aea 3051 }
3052 }
3053}
3054
5471d09a 3055int sshfwd_write(struct ssh_channel *c, char *buf, int len)
32874aea 3056{
51470298 3057 Ssh ssh = c->ssh;
3058
36f94d1f 3059 if (ssh->state != SSH_STATE_SESSION) {
3060 assert(ssh->state == SSH_STATE_CLOSED);
3061 return 0;
3062 }
3063
51470298 3064 if (ssh->version == 1) {
3065 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
32874aea 3066 PKT_INT, c->remoteid,
3067 PKT_INT, len, PKT_DATA, buf, len, PKT_END);
5471d09a 3068 /*
3069 * In SSH1 we can return 0 here - implying that forwarded
3070 * connections are never individually throttled - because
3071 * the only circumstance that can cause throttling will be
3072 * the whole SSH connection backing up, in which case
3073 * _everything_ will be throttled as a whole.
3074 */
3075 return 0;
783415f8 3076 } else {
32874aea 3077 ssh2_add_channel_data(c, buf, len);
5471d09a 3078 return ssh2_try_send(c);
3079 }
3080}
3081
3082void sshfwd_unthrottle(struct ssh_channel *c, int bufsize)
3083{
51470298 3084 Ssh ssh = c->ssh;
3085
36f94d1f 3086 if (ssh->state != SSH_STATE_SESSION) {
3087 assert(ssh->state == SSH_STATE_CLOSED);
3088 return;
3089 }
3090
51470298 3091 if (ssh->version == 1) {
5471d09a 3092 if (c->v.v1.throttling && bufsize < SSH1_BUFFER_LIMIT) {
3093 c->v.v1.throttling = 0;
51470298 3094 ssh1_throttle(ssh, -1);
5471d09a 3095 }
3096 } else {
3097 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
783415f8 3098 }
9c964e85 3099}
3100
51470298 3101static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
32874aea 3102{
51470298 3103 crBegin(ssh->ssh1_protocol_crstate);
fb09bf1c 3104
3105 random_init();
3106
51470298 3107 while (!do_ssh1_login(ssh, in, inlen, ispkt)) {
fb09bf1c 3108 crReturnV;
85ee8208 3109 }
51470298 3110 if (ssh->state == SSH_STATE_CLOSED)
32874aea 3111 crReturnV;
fb09bf1c 3112
86916870 3113 if (ssh->cfg.agentfwd && agent_exists()) {
32874aea 3114 logevent("Requesting agent forwarding");
51470298 3115 send_packet(ssh, SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
32874aea 3116 do {
3117 crReturnV;
3118 } while (!ispkt);
51470298 3119 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3120 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
6b5cf8b4 3121 bombout(("Protocol confusion"));
7ffdbc1a 3122 crStopV;
51470298 3123 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
32874aea 3124 logevent("Agent forwarding refused");
3125 } else {
3126 logevent("Agent forwarding enabled");
51470298 3127 ssh->agentfwd_enabled = TRUE;
db7d555c 3128 }
dacbd0e8 3129 }
3130
86916870 3131 if (ssh->cfg.x11_forward) {
32874aea 3132 char proto[20], data[64];
3133 logevent("Requesting X11 forwarding");
302121de 3134 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
86916870 3135 data, sizeof(data), ssh->cfg.x11_auth);
3136 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
51470298 3137 if (ssh->v1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) {
3138 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
32874aea 3139 PKT_STR, proto, PKT_STR, data,
86916870 3140 PKT_INT, x11_get_screen_number(ssh->cfg.x11_display),
421d6835 3141 PKT_END);
32874aea 3142 } else {
51470298 3143 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
32874aea 3144 PKT_STR, proto, PKT_STR, data, PKT_END);
3145 }
3146 do {
3147 crReturnV;
3148 } while (!ispkt);
51470298 3149 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3150 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
6b5cf8b4 3151 bombout(("Protocol confusion"));
7ffdbc1a 3152 crStopV;
51470298 3153 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
32874aea 3154 logevent("X11 forwarding refused");
3155 } else {
3156 logevent("X11 forwarding enabled");
51470298 3157 ssh->X11_fwd_enabled = TRUE;
9c964e85 3158 }
3159 }
3160
d74d141c 3161 {
9bf696b1 3162 char type;
d74d141c 3163 int n;
a4fc0d74 3164 int sport,dport,sserv,dserv;
6ee9b735 3165 char sports[256], dports[256], saddr[256], host[256];
d74d141c 3166
51470298 3167 ssh->rportfwds = newtree234(ssh_rportcmp_ssh1);
d74d141c 3168 /* Add port forwardings. */
86916870 3169 ssh->portfwd_strptr = ssh->cfg.portfwd;
51470298 3170 while (*ssh->portfwd_strptr) {
3171 type = *ssh->portfwd_strptr++;
6ee9b735 3172 saddr[0] = '\0';
d74d141c 3173 n = 0;
6ee9b735 3174 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != '\t') {
3175 if (*ssh->portfwd_strptr == ':') {
3176 /*
3177 * We've seen a colon in the middle of the
3178 * source port number. This means that
3179 * everything we've seen until now is the
3180 * source _address_, so we'll move it into
3181 * saddr and start sports from the beginning
3182 * again.
3183 */
3184 ssh->portfwd_strptr++;
3185 sports[n] = '\0';
3186 strcpy(saddr, sports);
3187 n = 0;
3188 }
3189 if (n < 255) sports[n++] = *ssh->portfwd_strptr++;
3190 }
d74d141c 3191 sports[n] = 0;
820ebe3b 3192 if (type != 'D') {
3193 if (*ssh->portfwd_strptr == '\t')
3194 ssh->portfwd_strptr++;
3195 n = 0;
3196 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != ':') {
3197 if (n < 255) host[n++] = *ssh->portfwd_strptr++;
3198 }
3199 host[n] = 0;
3200 if (*ssh->portfwd_strptr == ':')
3201 ssh->portfwd_strptr++;
3202 n = 0;
3203 while (*ssh->portfwd_strptr) {
3204 if (n < 255) dports[n++] = *ssh->portfwd_strptr++;
3205 }
3206 dports[n] = 0;
51470298 3207 ssh->portfwd_strptr++;
820ebe3b 3208 dport = atoi(dports);
3209 dserv = 0;
3210 if (dport == 0) {
3211 dserv = 1;
3212 dport = net_service_lookup(dports);
3213 if (!dport) {
3214 logeventf(ssh, "Service lookup failed for"
3215 " destination port \"%s\"", dports);
3216 }
a4fc0d74 3217 }
820ebe3b 3218 } else {
3219 while (*ssh->portfwd_strptr) ssh->portfwd_strptr++;
7ffdbc1a 3220 dport = dserv = -1;
a4fc0d74 3221 }
d74d141c 3222 sport = atoi(sports);
a4fc0d74 3223 sserv = 0;
3224 if (sport == 0) {
3225 sserv = 1;
68a49acb 3226 sport = net_service_lookup(sports);
3227 if (!sport) {
57356d63 3228 logeventf(ssh, "Service lookup failed for source"
3229 " port \"%s\"", sports);
a4fc0d74 3230 }
3231 }
d74d141c 3232 if (sport && dport) {
3233 if (type == 'L') {
6ee9b735 3234 pfd_addforward(host, dport, *saddr ? saddr : NULL,
e8fa8f62 3235 sport, ssh, &ssh->cfg);
6ee9b735 3236 logeventf(ssh, "Local port %.*s%.*s%.*s%.*s%d%.*s"
3237 " forwarding to %s:%.*s%.*s%d%.*s",
3238 (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
3239 (int)(*saddr?1:0), ":",
57356d63 3240 (int)(sserv ? strlen(sports) : 0), sports,
3241 sserv, "(", sport, sserv, ")",
3242 host,
3243 (int)(dserv ? strlen(dports) : 0), dports,
3244 dserv, "(", dport, dserv, ")");
820ebe3b 3245 } else if (type == 'D') {
3246 pfd_addforward(NULL, -1, *saddr ? saddr : NULL,
3247 sport, ssh, &ssh->cfg);
3248 logeventf(ssh, "Local port %.*s%.*s%.*s%.*s%d%.*s"
3249 " doing SOCKS dynamic forwarding",
3250 (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
3251 (int)(*saddr?1:0), ":",
3252 (int)(sserv ? strlen(sports) : 0), sports,
3253 sserv, "(", sport, sserv, ")");
d74d141c 3254 } else {
3255 struct ssh_rportfwd *pf;
3d88e64d 3256 pf = snew(struct ssh_rportfwd);
bc240b21 3257 strcpy(pf->dhost, host);
3258 pf->dport = dport;
6ee9b735 3259 if (saddr) {
3260 logeventf(ssh,
3261 "SSH1 cannot handle source address spec \"%s:%d\"; ignoring",
3262 saddr, sport);
3263 }
51470298 3264 if (add234(ssh->rportfwds, pf) != pf) {
57356d63 3265 logeventf(ssh,
3266 "Duplicate remote port forwarding to %s:%d",
3267 host, dport);
bc240b21 3268 sfree(pf);
d74d141c 3269 } else {
57356d63 3270 logeventf(ssh, "Requesting remote port %.*s%.*s%d%.*s"
3271 " forward to %s:%.*s%.*s%d%.*s",
3272 (int)(sserv ? strlen(sports) : 0), sports,
3273 sserv, "(", sport, sserv, ")",
3274 host,
3275 (int)(dserv ? strlen(dports) : 0), dports,
3276 dserv, "(", dport, dserv, ")");
51470298 3277 send_packet(ssh, SSH1_CMSG_PORT_FORWARD_REQUEST,
d74d141c 3278 PKT_INT, sport,
3279 PKT_STR, host,
3280 PKT_INT, dport,
3281 PKT_END);
9bf696b1 3282 do {
3283 crReturnV;
3284 } while (!ispkt);
51470298 3285 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3286 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
6b5cf8b4 3287 bombout(("Protocol confusion"));
7ffdbc1a 3288 crStopV;
51470298 3289 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
3290 c_write_str(ssh, "Server refused port"
3291 " forwarding\r\n");
9bf696b1 3292 }
3293 logevent("Remote port forwarding enabled");
d74d141c 3294 }
3295 }
3296 }
3297 }
3298 }
3299
86916870 3300 if (!ssh->cfg.nopty) {
51470298 3301 send_packet(ssh, SSH1_CMSG_REQUEST_PTY,
86916870 3302 PKT_STR, ssh->cfg.termtype,
51470298 3303 PKT_INT, ssh->term_height,
3304 PKT_INT, ssh->term_width,
32874aea 3305 PKT_INT, 0, PKT_INT, 0, PKT_CHAR, 0, PKT_END);
51470298 3306 ssh->state = SSH_STATE_INTERMED;
32874aea 3307 do {
3308 crReturnV;
3309 } while (!ispkt);
51470298 3310 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3311 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
6b5cf8b4 3312 bombout(("Protocol confusion"));
7ffdbc1a 3313 crStopV;
51470298 3314 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
3315 c_write_str(ssh, "Server refused to allocate pty\r\n");
3316 ssh->editing = ssh->echoing = 1;
32874aea 3317 }
c5e9c988 3318 logevent("Allocated pty");
0965bee0 3319 } else {
51470298 3320 ssh->editing = ssh->echoing = 1;
374330e2 3321 }
3322
86916870 3323 if (ssh->cfg.compression) {
51470298 3324 send_packet(ssh, SSH1_CMSG_REQUEST_COMPRESSION, PKT_INT, 6, PKT_END);
32874aea 3325 do {
3326 crReturnV;
3327 } while (!ispkt);
51470298 3328 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3329 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
6b5cf8b4 3330 bombout(("Protocol confusion"));
7ffdbc1a 3331 crStopV;
51470298 3332 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
3333 c_write_str(ssh, "Server refused to compress\r\n");
32874aea 3334 }
4ba9b64b 3335 logevent("Started compression");
51470298 3336 ssh->v1_compressing = TRUE;
5366aed8 3337 ssh->cs_comp_ctx = zlib_compress_init();
3338 logevent("Initialised zlib (RFC1950) compression");
3339 ssh->sc_comp_ctx = zlib_decompress_init();
3340 logevent("Initialised zlib (RFC1950) decompression");
4ba9b64b 3341 }
3342
fd5e5847 3343 /*
3344 * Start the shell or command.
3345 *
3346 * Special case: if the first-choice command is an SSH2
3347 * subsystem (hence not usable here) and the second choice
3348 * exists, we fall straight back to that.
3349 */
3350 {
86916870 3351 char *cmd = ssh->cfg.remote_cmd_ptr;
fd5e5847 3352
86916870 3353 if (ssh->cfg.ssh_subsys && ssh->cfg.remote_cmd_ptr2) {
3354 cmd = ssh->cfg.remote_cmd_ptr2;
51470298 3355 ssh->fallback_cmd = TRUE;
fd5e5847 3356 }
3357 if (*cmd)
51470298 3358 send_packet(ssh, SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END);
fd5e5847 3359 else
51470298 3360 send_packet(ssh, SSH1_CMSG_EXEC_SHELL, PKT_END);
fd5e5847 3361 logevent("Started session");
3362 }
374330e2 3363
51470298 3364 ssh->state = SSH_STATE_SESSION;
3365 if (ssh->size_needed)
3366 ssh_size(ssh, ssh->term_width, ssh->term_height);
3367 if (ssh->eof_needed)
3368 ssh_special(ssh, TS_EOF);
374330e2 3369
b9d7bcad 3370 if (ssh->ldisc)
3371 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
51470298 3372 ssh->send_ok = 1;
3373 ssh->channels = newtree234(ssh_channelcmp);
374330e2 3374 while (1) {
3375 crReturnV;
3376 if (ispkt) {
51470298 3377 if (ssh->pktin.type == SSH1_SMSG_STDOUT_DATA ||
3378 ssh->pktin.type == SSH1_SMSG_STDERR_DATA) {
3379 long len = GET_32BIT(ssh->pktin.body);
5471d09a 3380 int bufsize =
51470298 3381 from_backend(ssh->frontend,
3382 ssh->pktin.type == SSH1_SMSG_STDERR_DATA,
d8baa528 3383 (char *)(ssh->pktin.body) + 4, len);
51470298 3384 if (!ssh->v1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
3385 ssh->v1_stdout_throttling = 1;
3386 ssh1_throttle(ssh, +1);
5471d09a 3387 }
51470298 3388 } else if (ssh->pktin.type == SSH1_MSG_DISCONNECT) {
3bb2f322 3389 ssh_closing((Plug)ssh, NULL, 0, 0);
c5e9c988 3390 logevent("Received disconnect request");
7ffdbc1a 3391 crStopV;
51470298 3392 } else if (ssh->pktin.type == SSH1_SMSG_X11_OPEN) {
32874aea 3393 /* Remote side is trying to open a channel to talk to our
3394 * X-Server. Give them back a local channel number. */
3395 struct ssh_channel *c;
9c964e85 3396
3397 logevent("Received X11 connect request");
3398 /* Refuse if X11 forwarding is disabled. */
51470298 3399 if (!ssh->X11_fwd_enabled) {
3400 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
3401 PKT_INT, GET_32BIT(ssh->pktin.body), PKT_END);
9c964e85 3402 logevent("Rejected X11 connect request");
3403 } else {
3d88e64d 3404 c = snew(struct ssh_channel);
51470298 3405 c->ssh = ssh;
9c964e85 3406
86916870 3407 if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
e8fa8f62 3408 ssh->x11auth, NULL, -1, &ssh->cfg) != NULL) {
32874aea 3409 logevent("opening X11 forward connection failed");
3410 sfree(c);
51470298 3411 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
3412 PKT_INT, GET_32BIT(ssh->pktin.body),
32874aea 3413 PKT_END);
9c964e85 3414 } else {
32874aea 3415 logevent
3416 ("opening X11 forward connection succeeded");
51470298 3417 c->remoteid = GET_32BIT(ssh->pktin.body);
3418 c->localid = alloc_channel_id(ssh);
32874aea 3419 c->closes = 0;
5471d09a 3420 c->v.v1.throttling = 0;
32874aea 3421 c->type = CHAN_X11; /* identify channel type */
51470298 3422 add234(ssh->channels, c);
3423 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
32874aea 3424 PKT_INT, c->remoteid, PKT_INT,
3425 c->localid, PKT_END);
3426 logevent("Opened X11 forward channel");
9c964e85 3427 }
3428 }
51470298 3429 } else if (ssh->pktin.type == SSH1_SMSG_AGENT_OPEN) {
32874aea 3430 /* Remote side is trying to open a channel to talk to our
3431 * agent. Give them back a local channel number. */
3432 struct ssh_channel *c;
db7d555c 3433
3434 /* Refuse if agent forwarding is disabled. */
51470298 3435 if (!ssh->agentfwd_enabled) {
3436 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
3437 PKT_INT, GET_32BIT(ssh->pktin.body), PKT_END);
db7d555c 3438 } else {
3d88e64d 3439 c = snew(struct ssh_channel);
51470298 3440 c->ssh = ssh;
3441 c->remoteid = GET_32BIT(ssh->pktin.body);
3442 c->localid = alloc_channel_id(ssh);
db7d555c 3443 c->closes = 0;
5471d09a 3444 c->v.v1.throttling = 0;
32874aea 3445 c->type = CHAN_AGENT; /* identify channel type */
db7d555c 3446 c->u.a.lensofar = 0;
51470298 3447 add234(ssh->channels, c);
3448 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
db7d555c 3449 PKT_INT, c->remoteid, PKT_INT, c->localid,
3450 PKT_END);
3451 }
51470298 3452 } else if (ssh->pktin.type == SSH1_MSG_PORT_OPEN) {
d74d141c 3453 /* Remote side is trying to open a channel to talk to a
3454 * forwarded port. Give them back a local channel number. */
3455 struct ssh_channel *c;
3456 struct ssh_rportfwd pf;
3457 int hostsize, port;
3458 char host[256], buf[1024];
3459 char *p, *h, *e;
3d88e64d 3460 c = snew(struct ssh_channel);
51470298 3461 c->ssh = ssh;
d74d141c 3462
51470298 3463 hostsize = GET_32BIT(ssh->pktin.body+4);
d8baa528 3464 for (h = host, p = (char *)(ssh->pktin.body+8);
3465 hostsize != 0; hostsize--) {
d74d141c 3466 if (h+1 < host+sizeof(host))
3467 *h++ = *p;
95bc8819 3468 p++;
d74d141c 3469 }
3470 *h = 0;
3471 port = GET_32BIT(p);
3472
bc240b21 3473 strcpy(pf.dhost, host);
3474 pf.dport = port;
d74d141c 3475
51470298 3476 if (find234(ssh->rportfwds, &pf, NULL) == NULL) {
d74d141c 3477 sprintf(buf, "Rejected remote port open request for %s:%d",
3478 host, port);
3479 logevent(buf);
51470298 3480 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
3481 PKT_INT, GET_32BIT(ssh->pktin.body), PKT_END);
d74d141c 3482 } else {
3483 sprintf(buf, "Received remote port open request for %s:%d",
3484 host, port);
3485 logevent(buf);
e8fa8f62 3486 e = pfd_newconnect(&c->u.pfd.s, host, port, c, &ssh->cfg);
d74d141c 3487 if (e != NULL) {
3488 char buf[256];
3489 sprintf(buf, "Port open failed: %s", e);
3490 logevent(buf);
3491 sfree(c);
51470298 3492 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
3493 PKT_INT, GET_32BIT(ssh->pktin.body),
d74d141c 3494 PKT_END);
3495 } else {
51470298 3496 c->remoteid = GET_32BIT(ssh->pktin.body);
3497 c->localid = alloc_channel_id(ssh);
d74d141c 3498 c->closes = 0;
5471d09a 3499 c->v.v1.throttling = 0;
d74d141c 3500 c->type = CHAN_SOCKDATA; /* identify channel type */
51470298 3501 add234(ssh->channels, c);
3502 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
d74d141c 3503 PKT_INT, c->remoteid, PKT_INT,
3504 c->localid, PKT_END);
3505 logevent("Forwarded port opened successfully");
3506 }
3507 }
3508
51470298 3509 } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_OPEN_CONFIRMATION) {
3510 unsigned int remoteid = GET_32BIT(ssh->pktin.body);
3511 unsigned int localid = GET_32BIT(ssh->pktin.body+4);
bc240b21 3512 struct ssh_channel *c;
3513
51470298 3514 c = find234(ssh->channels, &remoteid, ssh_channelfind);
bc240b21 3515 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
3516 c->remoteid = localid;
3517 c->type = CHAN_SOCKDATA;
7781f316 3518 c->v.v1.throttling = 0;
bc240b21 3519 pfd_confirm(c->u.pfd.s);
3520 }
d74d141c 3521
4ed34d25 3522 if (c && c->closes) {
3523 /*
3524 * We have a pending close on this channel,
3525 * which we decided on before the server acked
3526 * the channel open. So now we know the
3527 * remoteid, we can close it again.
3528 */
51470298 3529 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE,
3530 PKT_INT, c->remoteid, PKT_END);
4ed34d25 3531 }
3532
51470298 3533 } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_OPEN_FAILURE) {
3534 unsigned int remoteid = GET_32BIT(ssh->pktin.body);
724cface 3535 struct ssh_channel *c;
3536
51470298 3537 c = find234(ssh->channels, &remoteid, ssh_channelfind);
724cface 3538 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
3539 logevent("Forwarded connection refused by server");
3540 pfd_close(c->u.pfd.s);
51470298 3541 del234(ssh->channels, c);
724cface 3542 sfree(c);
3543 }
3544
51470298 3545 } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE ||
3546 ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) {
32874aea 3547 /* Remote side closes a channel. */
51470298 3548 unsigned i = GET_32BIT(ssh->pktin.body);
32874aea 3549 struct ssh_channel *c;
51470298 3550 c = find234(ssh->channels, &i, ssh_channelfind);
d0d844c1 3551 if (c && ((int)c->remoteid) != -1) {
32874aea 3552 int closetype;
3553 closetype =
51470298 3554 (ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
0357890f 3555
783415f8 3556 if ((c->closes == 0) && (c->type == CHAN_X11)) {
d74d141c 3557 logevent("Forwarded X11 connection terminated");
9c964e85 3558 assert(c->u.x11.s != NULL);
3559 x11_close(c->u.x11.s);
3560 c->u.x11.s = NULL;
3561 }
d74d141c 3562 if ((c->closes == 0) && (c->type == CHAN_SOCKDATA)) {
3563 logevent("Forwarded port closed");
3564 assert(c->u.pfd.s != NULL);
3565 pfd_close(c->u.pfd.s);
3566 c->u.pfd.s = NULL;
3567 }
0357890f 3568
3569 c->closes |= (closetype << 2); /* seen this message */
3570 if (!(c->closes & closetype)) {
51470298 3571 send_packet(ssh, ssh->pktin.type, PKT_INT, c->remoteid,
0357890f 3572 PKT_END);
3573 c->closes |= closetype; /* sent it too */
3574 }
3575
3576 if (c->closes == 15) {
51470298 3577 del234(ssh->channels, c);
32874aea 3578 sfree(c);
3579 }
d0d844c1 3580 } else {
6b5cf8b4 3581 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
51470298 3582 ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE ? "" :
d0d844c1 3583 "_CONFIRMATION", c ? "half-open" : "nonexistent",
3584 i));
7ffdbc1a 3585 crStopV;
32874aea 3586 }
51470298 3587 } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_DATA) {
32874aea 3588 /* Data sent down one of our channels. */
51470298 3589 int i = GET_32BIT(ssh->pktin.body);
3590 int len = GET_32BIT(ssh->pktin.body + 4);
3591 unsigned char *p = ssh->pktin.body + 8;
32874aea 3592 struct ssh_channel *c;
51470298 3593 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 3594 if (c) {
7ffdbc1a 3595 int bufsize = 0;
32874aea 3596 switch (c->type) {
3597 case CHAN_X11:
d8baa528 3598 bufsize = x11_send(c->u.x11.s, (char *)p, len);
9c964e85 3599 break;
d74d141c 3600 case CHAN_SOCKDATA:
d8baa528 3601 bufsize = pfd_send(c->u.pfd.s, (char *)p, len);
bc240b21 3602 break;
32874aea 3603 case CHAN_AGENT:
3604 /* Data for an agent message. Buffer it. */
3605 while (len > 0) {
3606 if (c->u.a.lensofar < 4) {
3607 int l = min(4 - c->u.a.lensofar, len);
3608 memcpy(c->u.a.msglen + c->u.a.lensofar, p,
3609 l);
3610 p += l;
3611 len -= l;
3612 c->u.a.lensofar += l;
3613 }
3614 if (c->u.a.lensofar == 4) {
3615 c->u.a.totallen =
3616 4 + GET_32BIT(c->u.a.msglen);
3d88e64d 3617 c->u.a.message = snewn(c->u.a.totallen,
3618 unsigned char);
32874aea 3619 memcpy(c->u.a.message, c->u.a.msglen, 4);
3620 }
3621 if (c->u.a.lensofar >= 4 && len > 0) {
3622 int l =
3623 min(c->u.a.totallen - c->u.a.lensofar,
3624 len);
3625 memcpy(c->u.a.message + c->u.a.lensofar, p,
3626 l);
3627 p += l;
3628 len -= l;
3629 c->u.a.lensofar += l;
3630 }
3631 if (c->u.a.lensofar == c->u.a.totallen) {
3632 void *reply, *sentreply;
3633 int replylen;
3634 agent_query(c->u.a.message,
3635 c->u.a.totallen, &reply,
3636 &replylen);
3637 if (reply)
3638 sentreply = reply;
3639 else {
3640 /* Fake SSH_AGENT_FAILURE. */
3641 sentreply = "\0\0\0\1\5";
3642 replylen = 5;
3643 }
51470298 3644 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
32874aea 3645 PKT_INT, c->remoteid,
3646 PKT_INT, replylen,
3647 PKT_DATA, sentreply, replylen,
3648 PKT_END);
3649 if (reply)
3650 sfree(reply);
3651 sfree(c->u.a.message);
3652 c->u.a.lensofar = 0;
3653 }
3654 }
5471d09a 3655 bufsize = 0; /* agent channels never back up */
32874aea 3656 break;
3657 }
90347b95 3658 if (!c->v.v1.throttling && bufsize > SSH1_BUFFER_LIMIT) {
5471d09a 3659 c->v.v1.throttling = 1;
51470298 3660 ssh1_throttle(ssh, +1);
5471d09a 3661 }
32874aea 3662 }
51470298 3663 } else if (ssh->pktin.type == SSH1_SMSG_SUCCESS) {
972a41c8 3664 /* may be from EXEC_SHELL on some servers */
51470298 3665 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
972a41c8 3666 /* may be from EXEC_SHELL on some servers
374330e2 3667 * if no pty is available or in other odd cases. Ignore */
51470298 3668 } else if (ssh->pktin.type == SSH1_SMSG_EXIT_STATUS) {
d8d6c7e5 3669 char buf[100];
51470298 3670 ssh->exitcode = GET_32BIT(ssh->pktin.body);
d8d6c7e5 3671 sprintf(buf, "Server sent command exit status %d",
51470298 3672 ssh->exitcode);
d8d6c7e5 3673 logevent(buf);
51470298 3674 send_packet(ssh, SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
4252c9cc 3675 /*
3676 * In case `helpful' firewalls or proxies tack
3677 * extra human-readable text on the end of the
3678 * session which we might mistake for another
3679 * encrypted packet, we close the session once
3680 * we've sent EXIT_CONFIRMATION.
3681 */
3bb2f322 3682 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 3683 crStopV;
374330e2 3684 } else {
6b5cf8b4 3685 bombout(("Strange packet received: type %d", ssh->pktin.type));
7ffdbc1a 3686 crStopV;
374330e2 3687 }
3688 } else {
8df7a775 3689 while (inlen > 0) {
3690 int len = min(inlen, 512);
51470298 3691 send_packet(ssh, SSH1_CMSG_STDIN_DATA,
8df7a775 3692 PKT_INT, len, PKT_DATA, in, len, PKT_END);
3693 in += len;
3694 inlen -= len;
3695 }
374330e2 3696 }
3697 }
3698
3699 crFinishV;
3700}
3701
3702/*
e5574168 3703 * Utility routine for decoding comma-separated strings in KEXINIT.
3704 */
32874aea 3705static int in_commasep_string(char *needle, char *haystack, int haylen)
3706{
57356d63 3707 int needlen;
3708 if (!needle || !haystack) /* protect against null pointers */
3709 return 0;
3710 needlen = strlen(needle);
e5574168 3711 while (1) {
32874aea 3712 /*
3713 * Is it at the start of the string?
3714 */
3715 if (haylen >= needlen && /* haystack is long enough */
3716 !memcmp(needle, haystack, needlen) && /* initial match */
3717 (haylen == needlen || haystack[needlen] == ',')
3718 /* either , or EOS follows */
3719 )
3720 return 1;
3721 /*
3722 * If not, search for the next comma and resume after that.
3723 * If no comma found, terminate.
3724 */
3725 while (haylen > 0 && *haystack != ',')
3726 haylen--, haystack++;
3727 if (haylen == 0)
3728 return 0;
3729 haylen--, haystack++; /* skip over comma itself */
e5574168 3730 }
3731}
3732
3733/*
d39f364a 3734 * SSH2 key creation method.
3735 */
d8baa528 3736static void ssh2_mkkey(Ssh ssh, Bignum K, unsigned char *H,
3737 unsigned char *sessid, char chr,
3738 unsigned char *keyspace)
32874aea 3739{
d39f364a 3740 SHA_State s;
3741 /* First 20 bytes. */
3742 SHA_Init(&s);
51470298 3743 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
088bde77 3744 sha_mpint(&s, K);
d39f364a 3745 SHA_Bytes(&s, H, 20);
3746 SHA_Bytes(&s, &chr, 1);
5e0d7cb8 3747 SHA_Bytes(&s, sessid, 20);
d39f364a 3748 SHA_Final(&s, keyspace);
3749 /* Next 20 bytes. */
3750 SHA_Init(&s);
51470298 3751 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
088bde77 3752 sha_mpint(&s, K);
d39f364a 3753 SHA_Bytes(&s, H, 20);
3754 SHA_Bytes(&s, keyspace, 20);
32874aea 3755 SHA_Final(&s, keyspace + 20);
d39f364a 3756}
3757
3758/*
7cca0d81 3759 * Handle the SSH2 transport layer.
e5574168 3760 */
51470298 3761static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
e5574168 3762{
51470298 3763 struct do_ssh2_transport_state {
3764 int nbits, pbits, warn;
3765 Bignum p, g, e, f, K;
3766 int kex_init_value, kex_reply_value;
3767 const struct ssh_mac **maclist;
3768 int nmacs;
3769 const struct ssh2_cipher *cscipher_tobe;
3770 const struct ssh2_cipher *sccipher_tobe;
3771 const struct ssh_mac *csmac_tobe;
3772 const struct ssh_mac *scmac_tobe;
3773 const struct ssh_compress *cscomp_tobe;
3774 const struct ssh_compress *sccomp_tobe;
3775 char *hostkeydata, *sigdata, *keystr, *fingerprint;
3776 int hostkeylen, siglen;
3777 void *hkey; /* actual host key */
3778 unsigned char exchange_hash[20];
3779 int n_preferred_ciphers;
3780 const struct ssh2_ciphers *preferred_ciphers[CIPHER_MAX];
3781 const struct ssh_compress *preferred_comp;
3782 int first_kex;
3783 };
3784 crState(do_ssh2_transport_state);
3785
3786 crBegin(ssh->do_ssh2_transport_crstate);
3787
3788 s->cscipher_tobe = s->sccipher_tobe = NULL;
3789 s->csmac_tobe = s->scmac_tobe = NULL;
3790 s->cscomp_tobe = s->sccomp_tobe = NULL;
3791
7cca0d81 3792 random_init();
51470298 3793 s->first_kex = 1;
e5574168 3794
51470298 3795 {
3796 int i;
3797 /*
3798 * Set up the preferred ciphers. (NULL => warn below here)
3799 */
3800 s->n_preferred_ciphers = 0;
3801 for (i = 0; i < CIPHER_MAX; i++) {
86916870 3802 switch (ssh->cfg.ssh_cipherlist[i]) {
51470298 3803 case CIPHER_BLOWFISH:
3804 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_blowfish;
3805 break;
3806 case CIPHER_DES:
86916870 3807 if (ssh->cfg.ssh2_des_cbc) {
51470298 3808 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_des;
3809 }
3810 break;
3811 case CIPHER_3DES:
3812 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_3des;
3813 break;
3814 case CIPHER_AES:
3815 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_aes;
3816 break;
3817 case CIPHER_WARN:
3818 /* Flag for later. Don't bother if it's the last in
3819 * the list. */
3820 if (i < CIPHER_MAX - 1) {
3821 s->preferred_ciphers[s->n_preferred_ciphers++] = NULL;
3822 }
3823 break;
ca20bfcf 3824 }
ca20bfcf 3825 }
5e8358ad 3826 }
ca20bfcf 3827
3828 /*
3829 * Set up preferred compression.
3830 */
86916870 3831 if (ssh->cfg.compression)
51470298 3832 s->preferred_comp = &ssh_zlib;
4ba9b64b 3833 else
51470298 3834 s->preferred_comp = &ssh_comp_none;
5e8358ad 3835
7591b9ff 3836 /*
3837 * Be prepared to work around the buggy MAC problem.
3838 */
51470298 3839 if (ssh->remote_bugs & BUG_SSH2_HMAC)
3840 s->maclist = buggymacs, s->nmacs = lenof(buggymacs);
7591b9ff 3841 else
51470298 3842 s->maclist = macs, s->nmacs = lenof(macs);
7591b9ff 3843
32874aea 3844 begin_key_exchange:
51470298 3845 {
3846 int i, j, cipherstr_started;
3847
3848 /*
3849 * Construct and send our key exchange packet.
3850 */
3851 ssh2_pkt_init(ssh, SSH2_MSG_KEXINIT);
3852 for (i = 0; i < 16; i++)
3853 ssh2_pkt_addbyte(ssh, (unsigned char) random_byte());
3854 /* List key exchange algorithms. */
3855 ssh2_pkt_addstring_start(ssh);
3856 for (i = 0; i < lenof(kex_algs); i++) {
3857 if (kex_algs[i] == &ssh_diffiehellman_gex &&
3858 (ssh->remote_bugs & BUG_SSH2_DH_GEX))
3859 continue;
3860 ssh2_pkt_addstring_str(ssh, kex_algs[i]->name);
3861 if (i < lenof(kex_algs) - 1)
3862 ssh2_pkt_addstring_str(ssh, ",");
32874aea 3863 }
51470298 3864 /* List server host key algorithms. */
3865 ssh2_pkt_addstring_start(ssh);
3866 for (i = 0; i < lenof(hostkey_algs); i++) {
3867 ssh2_pkt_addstring_str(ssh, hostkey_algs[i]->name);
3868 if (i < lenof(hostkey_algs) - 1)
3869 ssh2_pkt_addstring_str(ssh, ",");
32874aea 3870 }
51470298 3871 /* List client->server encryption algorithms. */
3872 ssh2_pkt_addstring_start(ssh);
3873 cipherstr_started = 0;
3874 for (i = 0; i < s->n_preferred_ciphers; i++) {
3875 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
3876 if (!c) continue; /* warning flag */
3877 for (j = 0; j < c->nciphers; j++) {
3878 if (cipherstr_started)
3879 ssh2_pkt_addstring_str(ssh, ",");
3880 ssh2_pkt_addstring_str(ssh, c->list[j]->name);
3881 cipherstr_started = 1;
3882 }
3883 }
3884 /* List server->client encryption algorithms. */
3885 ssh2_pkt_addstring_start(ssh);
3886 cipherstr_started = 0;
3887 for (i = 0; i < s->n_preferred_ciphers; i++) {
3888 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
3889 if (!c) continue; /* warning flag */
3890 for (j = 0; j < c->nciphers; j++) {
3891 if (cipherstr_started)
3892 ssh2_pkt_addstring_str(ssh, ",");
3893 ssh2_pkt_addstring_str(ssh, c->list[j]->name);
3894 cipherstr_started = 1;
3895 }
3896 }
3897 /* List client->server MAC algorithms. */
3898 ssh2_pkt_addstring_start(ssh);
3899 for (i = 0; i < s->nmacs; i++) {
3900 ssh2_pkt_addstring_str(ssh, s->maclist[i]->name);
3901 if (i < s->nmacs - 1)
3902 ssh2_pkt_addstring_str(ssh, ",");
3903 }
3904 /* List server->client MAC algorithms. */
3905 ssh2_pkt_addstring_start(ssh);
3906 for (i = 0; i < s->nmacs; i++) {
3907 ssh2_pkt_addstring_str(ssh, s->maclist[i]->name);
3908 if (i < s->nmacs - 1)
3909 ssh2_pkt_addstring_str(ssh, ",");
3910 }
3911 /* List client->server compression algorithms. */
3912 ssh2_pkt_addstring_start(ssh);
3913 for (i = 0; i < lenof(compressions) + 1; i++) {
3914 const struct ssh_compress *c =
3915 i == 0 ? s->preferred_comp : compressions[i - 1];
3916 ssh2_pkt_addstring_str(ssh, c->name);
3917 if (i < lenof(compressions))
3918 ssh2_pkt_addstring_str(ssh, ",");
3919 }
3920 /* List server->client compression algorithms. */
3921 ssh2_pkt_addstring_start(ssh);
3922 for (i = 0; i < lenof(compressions) + 1; i++) {
3923 const struct ssh_compress *c =
3924 i == 0 ? s->preferred_comp : compressions[i - 1];
3925 ssh2_pkt_addstring_str(ssh, c->name);
3926 if (i < lenof(compressions))
3927 ssh2_pkt_addstring_str(ssh, ",");
3928 }
3929 /* List client->server languages. Empty list. */
3930 ssh2_pkt_addstring_start(ssh);
3931 /* List server->client languages. Empty list. */
3932 ssh2_pkt_addstring_start(ssh);
3933 /* First KEX packet does _not_ follow, because we're not that brave. */
3934 ssh2_pkt_addbool(ssh, FALSE);
3935 /* Reserved. */
3936 ssh2_pkt_adduint32(ssh, 0);
e5574168 3937 }
0db56f73 3938
51470298 3939 ssh->exhash = ssh->exhashbase;
3940 sha_string(&ssh->exhash, ssh->pktout.data + 5, ssh->pktout.length - 5);
0db56f73 3941
51470298 3942 ssh2_pkt_send(ssh);
e5574168 3943
32874aea 3944 if (!ispkt)
3945 crWaitUntil(ispkt);
57356d63 3946 if (ssh->pktin.length > 5)
3947 sha_string(&ssh->exhash, ssh->pktin.data + 5, ssh->pktin.length - 5);
e5574168 3948
3949 /*
3950 * Now examine the other side's KEXINIT to see what we're up
3951 * to.
3952 */
51470298 3953 {
3954 char *str;
3955 int i, j, len;
3956
3957 if (ssh->pktin.type != SSH2_MSG_KEXINIT) {
6b5cf8b4 3958 bombout(("expected key exchange packet from server"));
7ffdbc1a 3959 crStop(0);
32874aea 3960 }
51470298 3961 ssh->kex = NULL;
3962 ssh->hostkey = NULL;
3963 s->cscipher_tobe = NULL;
3964 s->sccipher_tobe = NULL;
3965 s->csmac_tobe = NULL;
3966 s->scmac_tobe = NULL;
3967 s->cscomp_tobe = NULL;
3968 s->sccomp_tobe = NULL;
3969 ssh->pktin.savedpos += 16; /* skip garbage cookie */
3970 ssh2_pkt_getstring(ssh, &str, &len); /* key exchange algorithms */
3971 for (i = 0; i < lenof(kex_algs); i++) {
3972 if (kex_algs[i] == &ssh_diffiehellman_gex &&
3973 (ssh->remote_bugs & BUG_SSH2_DH_GEX))
3974 continue;
3975 if (in_commasep_string(kex_algs[i]->name, str, len)) {
3976 ssh->kex = kex_algs[i];
3977 break;
3978 }
32874aea 3979 }
51470298 3980 ssh2_pkt_getstring(ssh, &str, &len); /* host key algorithms */
3981 for (i = 0; i < lenof(hostkey_algs); i++) {
3982 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
3983 ssh->hostkey = hostkey_algs[i];
3984 break;
3985 }
3986 }
3987 ssh2_pkt_getstring(ssh, &str, &len); /* client->server cipher */
3988 s->warn = 0;
3989 for (i = 0; i < s->n_preferred_ciphers; i++) {
3990 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
3991 if (!c) {
3992 s->warn = 1;
3993 } else {
3994 for (j = 0; j < c->nciphers; j++) {
3995 if (in_commasep_string(c->list[j]->name, str, len)) {
3996 s->cscipher_tobe = c->list[j];
3997 break;
3998 }
ca20bfcf 3999 }
32874aea 4000 }
51470298 4001 if (s->cscipher_tobe) {
4002 if (s->warn)
a8327734 4003 askcipher(ssh->frontend, s->cscipher_tobe->name, 1);
51470298 4004 break;
4005 }
32874aea 4006 }
51470298 4007 if (!s->cscipher_tobe) {
6b5cf8b4 4008 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
57356d63 4009 str ? str : "(null)"));
7ffdbc1a 4010 crStop(0);
ca20bfcf 4011 }
0ef8f407 4012
51470298 4013 ssh2_pkt_getstring(ssh, &str, &len); /* server->client cipher */
4014 s->warn = 0;
4015 for (i = 0; i < s->n_preferred_ciphers; i++) {
4016 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4017 if (!c) {
4018 s->warn = 1;
4019 } else {
4020 for (j = 0; j < c->nciphers; j++) {
4021 if (in_commasep_string(c->list[j]->name, str, len)) {
4022 s->sccipher_tobe = c->list[j];
4023 break;
4024 }
ca20bfcf 4025 }
32874aea 4026 }
51470298 4027 if (s->sccipher_tobe) {
4028 if (s->warn)
a8327734 4029 askcipher(ssh->frontend, s->sccipher_tobe->name, 2);
51470298 4030 break;
4031 }
32874aea 4032 }
51470298 4033 if (!s->sccipher_tobe) {
6b5cf8b4 4034 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
57356d63 4035 str ? str : "(null)"));
7ffdbc1a 4036 crStop(0);
ca20bfcf 4037 }
0ef8f407 4038
51470298 4039 ssh2_pkt_getstring(ssh, &str, &len); /* client->server mac */
4040 for (i = 0; i < s->nmacs; i++) {
4041 if (in_commasep_string(s->maclist[i]->name, str, len)) {
4042 s->csmac_tobe = s->maclist[i];
4043 break;
4044 }
32874aea 4045 }
51470298 4046 ssh2_pkt_getstring(ssh, &str, &len); /* server->client mac */
4047 for (i = 0; i < s->nmacs; i++) {
4048 if (in_commasep_string(s->maclist[i]->name, str, len)) {
4049 s->scmac_tobe = s->maclist[i];
4050 break;
4051 }
32874aea 4052 }
51470298 4053 ssh2_pkt_getstring(ssh, &str, &len); /* client->server compression */
4054 for (i = 0; i < lenof(compressions) + 1; i++) {
4055 const struct ssh_compress *c =
4056 i == 0 ? s->preferred_comp : compressions[i - 1];
4057 if (in_commasep_string(c->name, str, len)) {
4058 s->cscomp_tobe = c;
4059 break;
4060 }
32874aea 4061 }
51470298 4062 ssh2_pkt_getstring(ssh, &str, &len); /* server->client compression */
4063 for (i = 0; i < lenof(compressions) + 1; i++) {
4064 const struct ssh_compress *c =
4065 i == 0 ? s->preferred_comp : compressions[i - 1];
4066 if (in_commasep_string(c->name, str, len)) {
4067 s->sccomp_tobe = c;
4068 break;
4069 }
32874aea 4070 }
e5574168 4071 }
e5574168 4072
4073 /*
7bd5a860 4074 * Work out the number of bits of key we will need from the key
4075 * exchange. We start with the maximum key length of either
4076 * cipher...
4077 */
4078 {
32874aea 4079 int csbits, scbits;
7bd5a860 4080
51470298 4081 csbits = s->cscipher_tobe->keylen;
4082 scbits = s->sccipher_tobe->keylen;
4083 s->nbits = (csbits > scbits ? csbits : scbits);
7bd5a860 4084 }
4085 /* The keys only have 160-bit entropy, since they're based on
4086 * a SHA-1 hash. So cap the key size at 160 bits. */
51470298 4087 if (s->nbits > 160)
4088 s->nbits = 160;
7bd5a860 4089
4090 /*
a92dd380 4091 * If we're doing Diffie-Hellman group exchange, start by
4092 * requesting a group.
e5574168 4093 */
51470298 4094 if (ssh->kex == &ssh_diffiehellman_gex) {
32874aea 4095 logevent("Doing Diffie-Hellman group exchange");
51470298 4096 ssh->pkt_ctx |= SSH2_PKTCTX_DHGEX;
32874aea 4097 /*
4098 * Work out how big a DH group we will need to allow that
4099 * much data.
7bd5a860 4100 */
51470298 4101 s->pbits = 512 << ((s->nbits - 1) / 64);
4102 ssh2_pkt_init(ssh, SSH2_MSG_KEX_DH_GEX_REQUEST);
4103 ssh2_pkt_adduint32(ssh, s->pbits);
4104 ssh2_pkt_send(ssh);
32874aea 4105
4106 crWaitUntil(ispkt);
51470298 4107 if (ssh->pktin.type != SSH2_MSG_KEX_DH_GEX_GROUP) {
6b5cf8b4 4108 bombout(("expected key exchange group packet from server"));
7ffdbc1a 4109 crStop(0);
32874aea 4110 }
51470298 4111 s->p = ssh2_pkt_getmp(ssh);
4112 s->g = ssh2_pkt_getmp(ssh);
27cd7fc2 4113 ssh->kex_ctx = dh_setup_group(s->p, s->g);
51470298 4114 s->kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
4115 s->kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY;
a92dd380 4116 } else {
51470298 4117 ssh->pkt_ctx |= SSH2_PKTCTX_DHGROUP1;
27cd7fc2 4118 ssh->kex_ctx = dh_setup_group1();
51470298 4119 s->kex_init_value = SSH2_MSG_KEXDH_INIT;
4120 s->kex_reply_value = SSH2_MSG_KEXDH_REPLY;
8d5de777 4121 }
e5574168 4122
a92dd380 4123 logevent("Doing Diffie-Hellman key exchange");
e5574168 4124 /*
a92dd380 4125 * Now generate and send e for Diffie-Hellman.
e5574168 4126 */
27cd7fc2 4127 s->e = dh_create_e(ssh->kex_ctx, s->nbits * 2);
51470298 4128 ssh2_pkt_init(ssh, s->kex_init_value);
4129 ssh2_pkt_addmp(ssh, s->e);
4130 ssh2_pkt_send(ssh);
e5574168 4131
4132 crWaitUntil(ispkt);
51470298 4133 if (ssh->pktin.type != s->kex_reply_value) {
6b5cf8b4 4134 bombout(("expected key exchange reply packet from server"));
7ffdbc1a 4135 crStop(0);
7cca0d81 4136 }
51470298 4137 ssh2_pkt_getstring(ssh, &s->hostkeydata, &s->hostkeylen);
4138 s->f = ssh2_pkt_getmp(ssh);
4139 ssh2_pkt_getstring(ssh, &s->sigdata, &s->siglen);
e5574168 4140
27cd7fc2 4141 s->K = dh_find_K(ssh->kex_ctx, s->f);
e5574168 4142
51470298 4143 sha_string(&ssh->exhash, s->hostkeydata, s->hostkeylen);
4144 if (ssh->kex == &ssh_diffiehellman_gex) {
4145 sha_uint32(&ssh->exhash, s->pbits);
4146 sha_mpint(&ssh->exhash, s->p);
4147 sha_mpint(&ssh->exhash, s->g);
a92dd380 4148 }
51470298 4149 sha_mpint(&ssh->exhash, s->e);
4150 sha_mpint(&ssh->exhash, s->f);
4151 sha_mpint(&ssh->exhash, s->K);
4152 SHA_Final(&ssh->exhash, s->exchange_hash);
e5574168 4153
27cd7fc2 4154 dh_cleanup(ssh->kex_ctx);
fabd1805 4155 ssh->kex_ctx = NULL;
3709bfe9 4156
7cca0d81 4157#if 0
765c4200 4158 debug(("Exchange hash is:\n"));
51470298 4159 dmemdump(s->exchange_hash, 20);
7cca0d81 4160#endif
4161
51470298 4162 s->hkey = ssh->hostkey->newkey(s->hostkeydata, s->hostkeylen);
4163 if (!s->hkey ||
4164 !ssh->hostkey->verifysig(s->hkey, s->sigdata, s->siglen,
d8baa528 4165 (char *)s->exchange_hash, 20)) {
6b5cf8b4 4166 bombout(("Server's host key did not match the signature supplied"));
7ffdbc1a 4167 crStop(0);
8d5de777 4168 }
e5574168 4169
4170 /*
7cca0d81 4171 * Authenticate remote host: verify host key. (We've already
4172 * checked the signature of the exchange hash.)
e5574168 4173 */
51470298 4174 s->keystr = ssh->hostkey->fmtkey(s->hkey);
4175 s->fingerprint = ssh->hostkey->fingerprint(s->hkey);
a8327734 4176 verify_ssh_host_key(ssh->frontend,
4177 ssh->savedhost, ssh->savedport, ssh->hostkey->keytype,
51470298 4178 s->keystr, s->fingerprint);
4179 if (s->first_kex) { /* don't bother logging this in rekeys */
5e0d7cb8 4180 logevent("Host key fingerprint is:");
51470298 4181 logevent(s->fingerprint);
5e0d7cb8 4182 }
51470298 4183 sfree(s->fingerprint);
4184 sfree(s->keystr);
4185 ssh->hostkey->freekey(s->hkey);
d39f364a 4186
4187 /*
7cca0d81 4188 * Send SSH2_MSG_NEWKEYS.
d39f364a 4189 */
51470298 4190 ssh2_pkt_init(ssh, SSH2_MSG_NEWKEYS);
4191 ssh2_pkt_send(ssh);
d39f364a 4192
4193 /*
8406eaf9 4194 * Expect SSH2_MSG_NEWKEYS from server.
4195 */
4196 crWaitUntil(ispkt);
51470298 4197 if (ssh->pktin.type != SSH2_MSG_NEWKEYS) {
6b5cf8b4 4198 bombout(("expected new-keys packet from server"));
7ffdbc1a 4199 crStop(0);
8406eaf9 4200 }
4201
4202 /*
d39f364a 4203 * Create and initialise session keys.
4204 */
371e569c 4205 if (ssh->cs_cipher_ctx)
4206 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
51470298 4207 ssh->cscipher = s->cscipher_tobe;
371e569c 4208 ssh->cs_cipher_ctx = ssh->cscipher->make_context();
e0e1a00d 4209
371e569c 4210 if (ssh->sc_cipher_ctx)
4211 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
51470298 4212 ssh->sccipher = s->sccipher_tobe;
371e569c 4213 ssh->sc_cipher_ctx = ssh->sccipher->make_context();
e0e1a00d 4214
4215 if (ssh->cs_mac_ctx)
4216 ssh->csmac->free_context(ssh->cs_mac_ctx);
51470298 4217 ssh->csmac = s->csmac_tobe;
e0e1a00d 4218 ssh->cs_mac_ctx = ssh->csmac->make_context();
4219
4220 if (ssh->sc_mac_ctx)
4221 ssh->scmac->free_context(ssh->sc_mac_ctx);
51470298 4222 ssh->scmac = s->scmac_tobe;
e0e1a00d 4223 ssh->sc_mac_ctx = ssh->scmac->make_context();
4224
5366aed8 4225 if (ssh->cs_comp_ctx)
4226 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
51470298 4227 ssh->cscomp = s->cscomp_tobe;
5366aed8 4228 ssh->cs_comp_ctx = ssh->cscomp->compress_init();
4229
4230 if (ssh->sc_comp_ctx)
4231 ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
51470298 4232 ssh->sccomp = s->sccomp_tobe;
5366aed8 4233 ssh->sc_comp_ctx = ssh->sccomp->decompress_init();
4234
d39f364a 4235 /*
5e0d7cb8 4236 * Set IVs after keys. Here we use the exchange hash from the
4237 * _first_ key exchange.
d39f364a 4238 */
51470298 4239 {
4240 unsigned char keyspace[40];
4241 if (s->first_kex)
4242 memcpy(ssh->v2_session_id, s->exchange_hash,
4243 sizeof(s->exchange_hash));
4244 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'C',keyspace);
371e569c 4245 ssh->cscipher->setkey(ssh->cs_cipher_ctx, keyspace);
51470298 4246 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'D',keyspace);
371e569c 4247 ssh->sccipher->setkey(ssh->sc_cipher_ctx, keyspace);
51470298 4248 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'A',keyspace);
371e569c 4249 ssh->cscipher->setiv(ssh->cs_cipher_ctx, keyspace);
51470298 4250 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'B',keyspace);
371e569c 4251 ssh->sccipher->setiv(ssh->sc_cipher_ctx, keyspace);
51470298 4252 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'E',keyspace);
e0e1a00d 4253 ssh->csmac->setkey(ssh->cs_mac_ctx, keyspace);
51470298 4254 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'F',keyspace);
e0e1a00d 4255 ssh->scmac->setkey(ssh->sc_mac_ctx, keyspace);
51470298 4256 }
57356d63 4257 logeventf(ssh, "Initialised %.200s client->server encryption",
4258 ssh->cscipher->text_name);
4259 logeventf(ssh, "Initialised %.200s server->client encryption",
4260 ssh->sccipher->text_name);
4261 if (ssh->cscomp->text_name)
4262 logeventf(ssh, "Initialised %s compression",
4263 ssh->cscomp->text_name);
4264 if (ssh->sccomp->text_name)
4265 logeventf(ssh, "Initialised %s decompression",
4266 ssh->sccomp->text_name);
d39f364a 4267
033b4cef 4268 /*
0db56f73 4269 * If this is the first key exchange phase, we must pass the
4270 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
4271 * wants to see it but because it will need time to initialise
4272 * itself before it sees an actual packet. In subsequent key
4273 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
4274 * it would only confuse the layer above.
4275 */
51470298 4276 if (!s->first_kex) {
32874aea 4277 crReturn(0);
0db56f73 4278 }
51470298 4279 s->first_kex = 0;
0db56f73 4280
4281 /*
7cca0d81 4282 * Now we're encrypting. Begin returning 1 to the protocol main
4283 * function so that other things can run on top of the
4284 * transport. If we ever see a KEXINIT, we must go back to the
4285 * start.
033b4cef 4286 */
51470298 4287 while (!(ispkt && ssh->pktin.type == SSH2_MSG_KEXINIT)) {
32874aea 4288 crReturn(1);
e96adf72 4289 }
5e0d7cb8 4290 logevent("Server initiated key re-exchange");
7cca0d81 4291 goto begin_key_exchange;
e5574168 4292
4293 crFinish(1);
4294}
4295
7cca0d81 4296/*
783415f8 4297 * Add data to an SSH2 channel output buffer.
4298 */
32874aea 4299static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
4300 int len)
4301{
5471d09a 4302 bufchain_add(&c->v.v2.outbuffer, buf, len);
783415f8 4303}
4304
4305/*
4306 * Attempt to send data on an SSH2 channel.
4307 */
5471d09a 4308static int ssh2_try_send(struct ssh_channel *c)
32874aea 4309{
51470298 4310 Ssh ssh = c->ssh;
4311
5471d09a 4312 while (c->v.v2.remwindow > 0 && bufchain_size(&c->v.v2.outbuffer) > 0) {
4313 int len;
4314 void *data;
4315 bufchain_prefix(&c->v.v2.outbuffer, &data, &len);
4316 if ((unsigned)len > c->v.v2.remwindow)
4317 len = c->v.v2.remwindow;
4318 if ((unsigned)len > c->v.v2.remmaxpkt)
4319 len = c->v.v2.remmaxpkt;
51470298 4320 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_DATA);
4321 ssh2_pkt_adduint32(ssh, c->remoteid);
4322 ssh2_pkt_addstring_start(ssh);
4323 ssh2_pkt_addstring_data(ssh, data, len);
4324 ssh2_pkt_send(ssh);
5471d09a 4325 bufchain_consume(&c->v.v2.outbuffer, len);
4326 c->v.v2.remwindow -= len;
4327 }
4328
4329 /*
4330 * After having sent as much data as we can, return the amount
4331 * still buffered.
4332 */
4333 return bufchain_size(&c->v.v2.outbuffer);
4334}
4335
4336/*
4337 * Potentially enlarge the window on an SSH2 channel.
4338 */
4339static void ssh2_set_window(struct ssh_channel *c, unsigned newwin)
4340{
51470298 4341 Ssh ssh = c->ssh;
4342
6b69f42e 4343 /*
4344 * Never send WINDOW_ADJUST for a channel that the remote side
4345 * already thinks it's closed; there's no point, since it won't
4346 * be sending any more data anyway.
4347 */
4348 if (c->closes != 0)
4349 return;
4350
5471d09a 4351 if (newwin > c->v.v2.locwindow) {
51470298 4352 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST);
4353 ssh2_pkt_adduint32(ssh, c->remoteid);
4354 ssh2_pkt_adduint32(ssh, newwin - c->v.v2.locwindow);
4355 ssh2_pkt_send(ssh);
5471d09a 4356 c->v.v2.locwindow = newwin;
783415f8 4357 }
4358}
4359
4360/*
7cca0d81 4361 * Handle the SSH2 userauth and connection layers.
4362 */
51470298 4363static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
7cca0d81 4364{
51470298 4365 struct do_ssh2_authconn_state {
4366 enum {
4367 AUTH_INVALID, AUTH_PUBLICKEY_AGENT, AUTH_PUBLICKEY_FILE,
4368 AUTH_PASSWORD,
4369 AUTH_KEYBOARD_INTERACTIVE
4370 } method;
4371 enum {
4372 AUTH_TYPE_NONE,
4373 AUTH_TYPE_PUBLICKEY,
4374 AUTH_TYPE_PUBLICKEY_OFFER_LOUD,
4375 AUTH_TYPE_PUBLICKEY_OFFER_QUIET,
4376 AUTH_TYPE_PASSWORD,
4377 AUTH_TYPE_KEYBOARD_INTERACTIVE,
4378 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
4379 } type;
4380 int gotit, need_pw, can_pubkey, can_passwd, can_keyb_inter;
4381 int tried_pubkey_config, tried_agent, tried_keyb_inter;
4382 int kbd_inter_running;
4383 int we_are_in;
4384 int num_prompts, curr_prompt, echo;
4385 char username[100];
4386 int got_username;
4387 char pwprompt[200];
4388 char password[100];
4389 void *publickey_blob;
4390 int publickey_bloblen;
4391 unsigned char request[5], *response, *p;
4392 int responselen;
4393 int keyi, nkeys;
4394 int authed;
4395 char *pkblob, *alg, *commentp;
4396 int pklen, alglen, commentlen;
4397 int siglen, retlen, len;
4398 char *q, *agentreq, *ret;
4399 int try_send;
4400 };
4401 crState(do_ssh2_authconn_state);
4402
4403 crBegin(ssh->do_ssh2_authconn_crstate);
e5574168 4404
7cca0d81 4405 /*
4406 * Request userauth protocol, and await a response to it.
4407 */
51470298 4408 ssh2_pkt_init(ssh, SSH2_MSG_SERVICE_REQUEST);
4409 ssh2_pkt_addstring(ssh, "ssh-userauth");
4410 ssh2_pkt_send(ssh);
7cca0d81 4411 crWaitUntilV(ispkt);
51470298 4412 if (ssh->pktin.type != SSH2_MSG_SERVICE_ACCEPT) {
6b5cf8b4 4413 bombout(("Server refused user authentication protocol"));
7ffdbc1a 4414 crStopV;
8d5de777 4415 }
7cca0d81 4416
4417 /*
1408a877 4418 * We repeat this whole loop, including the username prompt,
4419 * until we manage a successful authentication. If the user
51470298 4420 * types the wrong _password_, they can be sent back to the
4421 * beginning to try another username, if this is configured on.
4422 * (If they specify a username in the config, they are never
4423 * asked, even if they do give a wrong password.)
1408a877 4424 *
4425 * I think this best serves the needs of
4426 *
4427 * - the people who have no configuration, no keys, and just
4428 * want to try repeated (username,password) pairs until they
4429 * type both correctly
4430 *
4431 * - people who have keys and configuration but occasionally
4432 * need to fall back to passwords
4433 *
4434 * - people with a key held in Pageant, who might not have
4435 * logged in to a particular machine before; so they want to
4436 * type a username, and then _either_ their key will be
4437 * accepted, _or_ they will type a password. If they mistype
4438 * the username they will want to be able to get back and
4439 * retype it!
7cca0d81 4440 */
51470298 4441 s->username[0] = '\0';
4442 s->got_username = FALSE;
1408a877 4443 do {
1408a877 4444 /*
4445 * Get a username.
4446 */
86916870 4447 if (s->got_username && !ssh->cfg.change_username) {
5bb641e1 4448 /*
4449 * We got a username last time round this loop, and
4450 * with change_username turned off we don't try to get
4451 * it again.
4452 */
86916870 4453 } else if ((flags & FLAG_INTERACTIVE) && !*ssh->cfg.username) {
c0a81592 4454 if (ssh_get_line && !ssh_getline_pw_only) {
32874aea 4455 if (!ssh_get_line("login as: ",
51470298 4456 s->username, sizeof(s->username), FALSE)) {
32874aea 4457 /*
4458 * get_line failed to get a username.
4459 * Terminate.
4460 */
4461 logevent("No username provided. Abandoning session.");
3bb2f322 4462 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 4463 crStopV;
32874aea 4464 }
4465 } else {
51470298 4466 int ret; /* need not be saved across crReturn */
4467 c_write_str(ssh, "login as: ");
4468 ssh->send_ok = 1;
4469 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
0405e71f 4470 do {
32874aea 4471 crWaitUntilV(!ispkt);
51470298 4472 ret = process_userpass_input(ssh, in, inlen);
0405e71f 4473 } while (ret == 0);
4474 if (ret < 0)
4475 cleanup_exit(0);
4ca0c9d1 4476 c_write_str(ssh, "\r\n");
32874aea 4477 }
51470298 4478 s->username[strcspn(s->username, "\n\r")] = '\0';
7cca0d81 4479 } else {
57356d63 4480 char *stuff;
86916870 4481 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
51470298 4482 s->username[sizeof(s->username)-1] = '\0';
65a22376 4483 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
57356d63 4484 stuff = dupprintf("Using username \"%s\".\r\n", s->username);
51470298 4485 c_write_str(ssh, stuff);
57356d63 4486 sfree(stuff);
7cca0d81 4487 }
4488 }
51470298 4489 s->got_username = TRUE;
7cca0d81 4490
65a22376 4491 /*
1408a877 4492 * Send an authentication request using method "none": (a)
4493 * just in case it succeeds, and (b) so that we know what
4494 * authentication methods we can usefully try next.
65a22376 4495 */
51470298 4496 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4497
4498 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4499 ssh2_pkt_addstring(ssh, s->username);
4500 ssh2_pkt_addstring(ssh, "ssh-connection");/* service requested */
4501 ssh2_pkt_addstring(ssh, "none"); /* method */
4502 ssh2_pkt_send(ssh);
4503 s->type = AUTH_TYPE_NONE;
4504 s->gotit = FALSE;
4505 s->we_are_in = FALSE;
4506
4507 s->tried_pubkey_config = FALSE;
4508 s->tried_agent = FALSE;
4509 s->tried_keyb_inter = FALSE;
4510 s->kbd_inter_running = FALSE;
86916870 4511 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
9a30e26b 4512 if (!filename_is_null(ssh->cfg.keyfile)) {
231ee168 4513 int keytype;
6c6d9ed9 4514 logeventf(ssh, "Reading private key file \"%.150s\"",
4515 filename_to_str(&ssh->cfg.keyfile));
9a30e26b 4516 keytype = key_type(&ssh->cfg.keyfile);
51470298 4517 if (keytype == SSH_KEYTYPE_SSH2) {
4518 s->publickey_blob =
9a30e26b 4519 ssh2_userkey_loadpub(&ssh->cfg.keyfile, NULL,
51470298 4520 &s->publickey_bloblen);
4521 } else {
57356d63 4522 char *msgbuf;
c2ad7d0d 4523 logeventf(ssh, "Unable to use this key file (%s)",
a8327734 4524 key_type_to_str(keytype));
57356d63 4525 msgbuf = dupprintf("Unable to use key file \"%.150s\""
6c6d9ed9 4526 " (%s)\r\n",
4527 filename_to_str(&ssh->cfg.keyfile),
57356d63 4528 key_type_to_str(keytype));
51470298 4529 c_write_str(ssh, msgbuf);
57356d63 4530 sfree(msgbuf);
51470298 4531 s->publickey_blob = NULL;
231ee168 4532 }
396778f1 4533 } else
51470298 4534 s->publickey_blob = NULL;
65a22376 4535
1408a877 4536 while (1) {
4537 /*
4538 * Wait for the result of the last authentication request.
4539 */
51470298 4540 if (!s->gotit)
1408a877 4541 crWaitUntilV(ispkt);
51470298 4542 while (ssh->pktin.type == SSH2_MSG_USERAUTH_BANNER) {
32874aea 4543 char *banner;
4544 int size;
4545 /*
4546 * Don't show the banner if we're operating in
4547 * non-verbose non-interactive mode. (It's probably
4548 * a script, which means nobody will read the
4549 * banner _anyway_, and moreover the printing of
4550 * the banner will screw up processing on the
4551 * output of (say) plink.)
4552 */
4553 if (flags & (FLAG_VERBOSE | FLAG_INTERACTIVE)) {
51470298 4554 ssh2_pkt_getstring(ssh, &banner, &size);
32874aea 4555 if (banner)
51470298 4556 c_write_untrusted(ssh, banner, size);
32874aea 4557 }
1408a877 4558 crWaitUntilV(ispkt);
4559 }
51470298 4560 if (ssh->pktin.type == SSH2_MSG_USERAUTH_SUCCESS) {
1408a877 4561 logevent("Access granted");
51470298 4562 s->we_are_in = TRUE;
1408a877 4563 break;
4564 }
65a22376 4565
51470298 4566 if (s->kbd_inter_running &&
4567 ssh->pktin.type == SSH2_MSG_USERAUTH_INFO_REQUEST) {
b3186d64 4568 /*
45068b27 4569 * This is either a further set-of-prompts packet
4570 * in keyboard-interactive authentication, or it's
4571 * the same one and we came back here with `gotit'
4572 * set. In the former case, we must reset the
4573 * curr_prompt variable.
b3186d64 4574 */
51470298 4575 if (!s->gotit)
4576 s->curr_prompt = 0;
4577 } else if (ssh->pktin.type != SSH2_MSG_USERAUTH_FAILURE) {
6b5cf8b4 4578 bombout(("Strange packet received during authentication: type %d",
51470298 4579 ssh->pktin.type));
7ffdbc1a 4580 crStopV;
65a22376 4581 }
4582
51470298 4583 s->gotit = FALSE;
65a22376 4584
1408a877 4585 /*
4586 * OK, we're now sitting on a USERAUTH_FAILURE message, so
4587 * we can look at the string in it and know what we can
4588 * helpfully try next.
4589 */
51470298 4590 if (ssh->pktin.type == SSH2_MSG_USERAUTH_FAILURE) {
1408a877 4591 char *methods;
4592 int methlen;
51470298 4593 ssh2_pkt_getstring(ssh, &methods, &methlen);
4594 s->kbd_inter_running = FALSE;
4595 if (!ssh2_pkt_getbool(ssh)) {
1408a877 4596 /*
4597 * We have received an unequivocal Access
4598 * Denied. This can translate to a variety of
4599 * messages:
4600 *
4601 * - if we'd just tried "none" authentication,
4602 * it's not worth printing anything at all
4603 *
4604 * - if we'd just tried a public key _offer_,
4605 * the message should be "Server refused our
4606 * key" (or no message at all if the key
4607 * came from Pageant)
4608 *
4609 * - if we'd just tried anything else, the
4610 * message really should be "Access denied".
4611 *
4612 * Additionally, if we'd just tried password
4613 * authentication, we should break out of this
4614 * whole loop so as to go back to the username
4615 * prompt.
4616 */
51470298 4617 if (s->type == AUTH_TYPE_NONE) {
1408a877 4618 /* do nothing */
51470298 4619 } else if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD ||
4620 s->type == AUTH_TYPE_PUBLICKEY_OFFER_QUIET) {
4621 if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD)
4622 c_write_str(ssh, "Server refused our key\r\n");
1408a877 4623 logevent("Server refused public key");
51470298 4624 } else if (s->type==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET) {
4bdf7c46 4625 /* server declined keyboard-interactive; ignore */
1408a877 4626 } else {
51470298 4627 c_write_str(ssh, "Access denied\r\n");
1408a877 4628 logevent("Access denied");
51470298 4629 if (s->type == AUTH_TYPE_PASSWORD) {
4630 s->we_are_in = FALSE;
1408a877 4631 break;
4632 }
4633 }
4634 } else {
51470298 4635 c_write_str(ssh, "Further authentication required\r\n");
1408a877 4636 logevent("Further authentication required");
4637 }
65a22376 4638
51470298 4639 s->can_pubkey =
32874aea 4640 in_commasep_string("publickey", methods, methlen);
51470298 4641 s->can_passwd =
32874aea 4642 in_commasep_string("password", methods, methlen);
86916870 4643 s->can_keyb_inter = ssh->cfg.try_ki_auth &&
761187b6 4644 in_commasep_string("keyboard-interactive", methods, methlen);
1408a877 4645 }
65a22376 4646
51470298 4647 s->method = 0;
4648 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
65a22376 4649
0405e71f 4650 /*
4651 * Most password/passphrase prompts will be
4652 * non-echoing, so we set this to 0 by default.
4653 * Exception is that some keyboard-interactive prompts
4654 * can be echoing, in which case we'll set this to 1.
4655 */
51470298 4656 s->echo = 0;
0405e71f 4657
51470298 4658 if (!s->method && s->can_pubkey &&
4659 agent_exists() && !s->tried_agent) {
1983e559 4660 /*
4661 * Attempt public-key authentication using Pageant.
4662 */
1983e559 4663 void *r;
51470298 4664 s->authed = FALSE;
1983e559 4665
51470298 4666 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4667 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
00db133f 4668
51470298 4669 s->tried_agent = TRUE;
1983e559 4670
4671 logevent("Pageant is running. Requesting keys.");
4672
4673 /* Request the keys held by the agent. */
51470298 4674 PUT_32BIT(s->request, 1);
4675 s->request[4] = SSH2_AGENTC_REQUEST_IDENTITIES;
4676 agent_query(s->request, 5, &r, &s->responselen);
4677 s->response = (unsigned char *) r;
4678 if (s->response && s->responselen >= 5 &&
4679 s->response[4] == SSH2_AGENT_IDENTITIES_ANSWER) {
4680 s->p = s->response + 5;
4681 s->nkeys = GET_32BIT(s->p);
4682 s->p += 4;
32874aea 4683 {
4684 char buf[64];
51470298 4685 sprintf(buf, "Pageant has %d SSH2 keys", s->nkeys);
32874aea 4686 logevent(buf);
4687 }
51470298 4688 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
2d466ffd 4689 void *vret;
1983e559 4690
32874aea 4691 {
4692 char buf[64];
51470298 4693 sprintf(buf, "Trying Pageant key #%d", s->keyi);
32874aea 4694 logevent(buf);
4695 }
51470298 4696 s->pklen = GET_32BIT(s->p);
4697 s->p += 4;
4698 if (s->publickey_blob &&
4699 s->pklen == s->publickey_bloblen &&
4700 !memcmp(s->p, s->publickey_blob,
4701 s->publickey_bloblen)) {
396778f1 4702 logevent("This key matches configured key file");
51470298 4703 s->tried_pubkey_config = 1;
396778f1 4704 }
d8baa528 4705 s->pkblob = (char *)s->p;
51470298 4706 s->p += s->pklen;
4707 s->alglen = GET_32BIT(s->pkblob);
4708 s->alg = s->pkblob + 4;
4709 s->commentlen = GET_32BIT(s->p);
4710 s->p += 4;
d8baa528 4711 s->commentp = (char *)s->p;
51470298 4712 s->p += s->commentlen;
4713 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4714 ssh2_pkt_addstring(ssh, s->username);
4715 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
4716 ssh2_pkt_addstring(ssh, "publickey"); /* method */
4717 ssh2_pkt_addbool(ssh, FALSE); /* no signature included */
4718 ssh2_pkt_addstring_start(ssh);
4719 ssh2_pkt_addstring_data(ssh, s->alg, s->alglen);
4720 ssh2_pkt_addstring_start(ssh);
4721 ssh2_pkt_addstring_data(ssh, s->pkblob, s->pklen);
4722 ssh2_pkt_send(ssh);
1983e559 4723
4724 crWaitUntilV(ispkt);
51470298 4725 if (ssh->pktin.type != SSH2_MSG_USERAUTH_PK_OK) {
1983e559 4726 logevent("Key refused");
4727 continue;
4728 }
4729
32874aea 4730 if (flags & FLAG_VERBOSE) {
51470298 4731 c_write_str(ssh, "Authenticating with "
4732 "public key \"");
4733 c_write(ssh, s->commentp, s->commentlen);
4734 c_write_str(ssh, "\" from agent\r\n");
32874aea 4735 }
1983e559 4736
4737 /*
4738 * Server is willing to accept the key.
4739 * Construct a SIGN_REQUEST.
4740 */
51470298 4741 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4742 ssh2_pkt_addstring(ssh, s->username);
4743 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
4744 ssh2_pkt_addstring(ssh, "publickey"); /* method */
4745 ssh2_pkt_addbool(ssh, TRUE);
4746 ssh2_pkt_addstring_start(ssh);
4747 ssh2_pkt_addstring_data(ssh, s->alg, s->alglen);
4748 ssh2_pkt_addstring_start(ssh);
4749 ssh2_pkt_addstring_data(ssh, s->pkblob, s->pklen);
4750
4751 s->siglen = ssh->pktout.length - 5 + 4 + 20;
dda87a28 4752 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
4753 s->siglen -= 4;
51470298 4754 s->len = 1; /* message type */
4755 s->len += 4 + s->pklen; /* key blob */
4756 s->len += 4 + s->siglen; /* data to sign */
4757 s->len += 4; /* flags */
3d88e64d 4758 s->agentreq = snewn(4 + s->len, char);
51470298 4759 PUT_32BIT(s->agentreq, s->len);
4760 s->q = s->agentreq + 4;
4761 *s->q++ = SSH2_AGENTC_SIGN_REQUEST;
4762 PUT_32BIT(s->q, s->pklen);
4763 s->q += 4;
4764 memcpy(s->q, s->pkblob, s->pklen);
4765 s->q += s->pklen;
4766 PUT_32BIT(s->q, s->siglen);
4767 s->q += 4;
1983e559 4768 /* Now the data to be signed... */
dda87a28 4769 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
4770 PUT_32BIT(s->q, 20);
4771 s->q += 4;
4772 }
51470298 4773 memcpy(s->q, ssh->v2_session_id, 20);
4774 s->q += 20;
4775 memcpy(s->q, ssh->pktout.data + 5,
4776 ssh->pktout.length - 5);
4777 s->q += ssh->pktout.length - 5;
1983e559 4778 /* And finally the (zero) flags word. */
51470298 4779 PUT_32BIT(s->q, 0);
4780 agent_query(s->agentreq, s->len + 4, &vret, &s->retlen);
4781 s->ret = vret;
4782 sfree(s->agentreq);
4783 if (s->ret) {
4784 if (s->ret[4] == SSH2_AGENT_SIGN_RESPONSE) {
1983e559 4785 logevent("Sending Pageant's response");
51470298 4786 ssh2_add_sigblob(ssh, s->pkblob, s->pklen,
4787 s->ret + 9,
4788 GET_32BIT(s->ret + 5));
4789 ssh2_pkt_send(ssh);
4790 s->authed = TRUE;
1983e559 4791 break;
4792 } else {
32874aea 4793 logevent
4794 ("Pageant failed to answer challenge");
51470298 4795 sfree(s->ret);
1983e559 4796 }
4797 }
4798 }
51470298 4799 if (s->authed)
1983e559 4800 continue;
4801 }
4802 }
4803
51470298 4804 if (!s->method && s->can_pubkey && s->publickey_blob
4805 && !s->tried_pubkey_config) {
1408a877 4806 unsigned char *pub_blob;
4807 char *algorithm, *comment;
4808 int pub_blob_len;
65a22376 4809
51470298 4810 s->tried_pubkey_config = TRUE;
65a22376 4811
51470298 4812 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4813 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
00db133f 4814
65a22376 4815 /*
1408a877 4816 * Try the public key supplied in the configuration.
4817 *
4818 * First, offer the public blob to see if the server is
4819 * willing to accept it.
65a22376 4820 */
d8baa528 4821 pub_blob =
9a30e26b 4822 (unsigned char *)ssh2_userkey_loadpub(&ssh->cfg.keyfile,
d8baa528 4823 &algorithm,
4824 &pub_blob_len);
1408a877 4825 if (pub_blob) {
51470298 4826 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4827 ssh2_pkt_addstring(ssh, s->username);
4828 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
4829 ssh2_pkt_addstring(ssh, "publickey"); /* method */
4830 ssh2_pkt_addbool(ssh, FALSE); /* no signature included */
4831 ssh2_pkt_addstring(ssh, algorithm);
4832 ssh2_pkt_addstring_start(ssh);
d8baa528 4833 ssh2_pkt_addstring_data(ssh, (char *)pub_blob,
4834 pub_blob_len);
51470298 4835 ssh2_pkt_send(ssh);
32874aea 4836 logevent("Offered public key"); /* FIXME */
1408a877 4837
4838 crWaitUntilV(ispkt);
51470298 4839 if (ssh->pktin.type != SSH2_MSG_USERAUTH_PK_OK) {
4840 s->gotit = TRUE;
4841 s->type = AUTH_TYPE_PUBLICKEY_OFFER_LOUD;
32874aea 4842 continue; /* key refused; give up on it */
1408a877 4843 }
65a22376 4844
1408a877 4845 logevent("Offer of public key accepted");
65a22376 4846 /*
1408a877 4847 * Actually attempt a serious authentication using
4848 * the key.
65a22376 4849 */
9a30e26b 4850 if (ssh2_userkey_encrypted(&ssh->cfg.keyfile, &comment)) {
51470298 4851 sprintf(s->pwprompt,
32874aea 4852 "Passphrase for key \"%.100s\": ",
4853 comment);
51470298 4854 s->need_pw = TRUE;
1408a877 4855 } else {
51470298 4856 s->need_pw = FALSE;
1408a877 4857 }
51470298 4858 c_write_str(ssh, "Authenticating with public key \"");
4859 c_write_str(ssh, comment);
4860 c_write_str(ssh, "\"\r\n");
4861 s->method = AUTH_PUBLICKEY_FILE;
65a22376 4862 }
1408a877 4863 }
4864
51470298 4865 if (!s->method && s->can_keyb_inter && !s->tried_keyb_inter) {
4866 s->method = AUTH_KEYBOARD_INTERACTIVE;
4867 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
4868 s->tried_keyb_inter = TRUE;
af659722 4869
51470298 4870 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4871 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
00db133f 4872
51470298 4873 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4874 ssh2_pkt_addstring(ssh, s->username);
4875 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
4876 ssh2_pkt_addstring(ssh, "keyboard-interactive"); /* method */
4877 ssh2_pkt_addstring(ssh, ""); /* lang */
4878 ssh2_pkt_addstring(ssh, "");
4879 ssh2_pkt_send(ssh);
af659722 4880
4881 crWaitUntilV(ispkt);
51470298 4882 if (ssh->pktin.type != SSH2_MSG_USERAUTH_INFO_REQUEST) {
4883 if (ssh->pktin.type == SSH2_MSG_USERAUTH_FAILURE)
4884 s->gotit = TRUE;
af659722 4885 logevent("Keyboard-interactive authentication refused");
51470298 4886 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET;
af659722 4887 continue;
4888 }
4889
51470298 4890 s->kbd_inter_running = TRUE;
4891 s->curr_prompt = 0;
af659722 4892 }
4893
51470298 4894 if (s->kbd_inter_running) {
4895 s->method = AUTH_KEYBOARD_INTERACTIVE;
4896 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
4897 s->tried_keyb_inter = TRUE;
af659722 4898
51470298 4899 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4900 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
00db133f 4901
51470298 4902 if (s->curr_prompt == 0) {
45068b27 4903 /*
4904 * We've got a fresh USERAUTH_INFO_REQUEST.
4905 * Display header data, and start going through
4906 * the prompts.
4907 */
4908 char *name, *inst, *lang;
4909 int name_len, inst_len, lang_len;
4910
51470298 4911 ssh2_pkt_getstring(ssh, &name, &name_len);
4912 ssh2_pkt_getstring(ssh, &inst, &inst_len);
4913 ssh2_pkt_getstring(ssh, &lang, &lang_len);
45068b27 4914 if (name_len > 0) {
51470298 4915 c_write_untrusted(ssh, name, name_len);
4916 c_write_str(ssh, "\r\n");
45068b27 4917 }
4918 if (inst_len > 0) {
51470298 4919 c_write_untrusted(ssh, inst, inst_len);
4920 c_write_str(ssh, "\r\n");
45068b27 4921 }
51470298 4922 s->num_prompts = ssh2_pkt_getuint32(ssh);
45068b27 4923 }
af659722 4924
45068b27 4925 /*
4926 * If there are prompts remaining in the packet,
4927 * display one and get a response.
4928 */
51470298 4929 if (s->curr_prompt < s->num_prompts) {
45068b27 4930 char *prompt;
4931 int prompt_len;
af659722 4932
51470298 4933 ssh2_pkt_getstring(ssh, &prompt, &prompt_len);
45068b27 4934 if (prompt_len > 0) {
51470298 4935 strncpy(s->pwprompt, prompt, sizeof(s->pwprompt));
4936 s->pwprompt[prompt_len < sizeof(s->pwprompt) ?
4937 prompt_len : sizeof(s->pwprompt)-1] = '\0';
45068b27 4938 } else {
51470298 4939 strcpy(s->pwprompt,
45068b27 4940 "<server failed to send prompt>: ");
4941 }
51470298 4942 s->echo = ssh2_pkt_getbool(ssh);
4943 s->need_pw = TRUE;
45068b27 4944 } else
51470298 4945 s->need_pw = FALSE;
af659722 4946 }
4947
51470298 4948 if (!s->method && s->can_passwd) {
4949 s->method = AUTH_PASSWORD;
4950 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4951 ssh->pkt_ctx |= SSH2_PKTCTX_PASSWORD;
4952 sprintf(s->pwprompt, "%.90s@%.90s's password: ", s->username,
4953 ssh->savedhost);
4954 s->need_pw = TRUE;
1408a877 4955 }
4956
51470298 4957 if (s->need_pw) {
fa17a66e 4958 if (ssh_get_line) {
51470298 4959 if (!ssh_get_line(s->pwprompt, s->password,
4960 sizeof(s->password), TRUE)) {
1408a877 4961 /*
fa17a66e 4962 * get_line failed to get a password (for
4963 * example because one was supplied on the
4964 * command line which has already failed to
4965 * work). Terminate.
1408a877 4966 */
51470298 4967 ssh2_pkt_init(ssh, SSH2_MSG_DISCONNECT);
4968 ssh2_pkt_adduint32(ssh,SSH2_DISCONNECT_BY_APPLICATION);
4969 ssh2_pkt_addstring(ssh, "No more passwords available"
4970 " to try");
4971 ssh2_pkt_addstring(ssh, "en"); /* language tag */
4972 ssh2_pkt_send(ssh);
247308b5 4973 logevent("Unable to authenticate");
a8327734 4974 connection_fatal(ssh->frontend,
4975 "Unable to authenticate");
3bb2f322 4976 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 4977 crStopV;
1408a877 4978 }
4979 } else {
51470298 4980 int ret; /* need not be saved across crReturn */
4981 c_write_untrusted(ssh, s->pwprompt, strlen(s->pwprompt));
4982 ssh->send_ok = 1;
1408a877 4983
51470298 4984 setup_userpass_input(ssh, s->password,
4985 sizeof(s->password), s->echo);
0405e71f 4986 do {
1408a877 4987 crWaitUntilV(!ispkt);
51470298 4988 ret = process_userpass_input(ssh, in, inlen);
0405e71f 4989 } while (ret == 0);
4990 if (ret < 0)
4991 cleanup_exit(0);
51470298 4992 c_write_str(ssh, "\r\n");
65a22376 4993 }
65a22376 4994 }
65a22376 4995
51470298 4996 if (s->method == AUTH_PUBLICKEY_FILE) {
1408a877 4997 /*
4998 * We have our passphrase. Now try the actual authentication.
4999 */
5000 struct ssh2_userkey *key;
65a22376 5001
9a30e26b 5002 key = ssh2_load_userkey(&ssh->cfg.keyfile, s->password);
1408a877 5003 if (key == SSH2_WRONG_PASSPHRASE || key == NULL) {
5004 if (key == SSH2_WRONG_PASSPHRASE) {
51470298 5005 c_write_str(ssh, "Wrong passphrase\r\n");
5006 s->tried_pubkey_config = FALSE;
1408a877 5007 } else {
51470298 5008 c_write_str(ssh, "Unable to load private key\r\n");
5009 s->tried_pubkey_config = TRUE;
1408a877 5010 }
5011 /* Send a spurious AUTH_NONE to return to the top. */
51470298 5012 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
5013 ssh2_pkt_addstring(ssh, s->username);
5014 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
5015 ssh2_pkt_addstring(ssh, "none"); /* method */
5016 ssh2_pkt_send(ssh);
5017 s->type = AUTH_TYPE_NONE;
1408a877 5018 } else {
1dd353b5 5019 unsigned char *pkblob, *sigblob, *sigdata;
5020 int pkblob_len, sigblob_len, sigdata_len;
dda87a28 5021 int p;
65a22376 5022
1408a877 5023 /*
5024 * We have loaded the private key and the server
5025 * has announced that it's willing to accept it.
5026 * Hallelujah. Generate a signature and send it.
5027 */
51470298 5028 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
5029 ssh2_pkt_addstring(ssh, s->username);
5030 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
5031 ssh2_pkt_addstring(ssh, "publickey"); /* method */
5032 ssh2_pkt_addbool(ssh, TRUE);
5033 ssh2_pkt_addstring(ssh, key->alg->name);
1dd353b5 5034 pkblob = key->alg->public_blob(key->data, &pkblob_len);
51470298 5035 ssh2_pkt_addstring_start(ssh);
d8baa528 5036 ssh2_pkt_addstring_data(ssh, (char *)pkblob, pkblob_len);
1408a877 5037
5038 /*
5039 * The data to be signed is:
5040 *
5041 * string session-id
5042 *
5043 * followed by everything so far placed in the
5044 * outgoing packet.
5045 */
51470298 5046 sigdata_len = ssh->pktout.length - 5 + 4 + 20;
dda87a28 5047 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
5048 sigdata_len -= 4;
92d60585 5049 sigdata = snewn(sigdata_len, unsigned char);
dda87a28 5050 p = 0;
5051 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
5052 PUT_32BIT(sigdata+p, 20);
5053 p += 4;
5054 }
5055 memcpy(sigdata+p, ssh->v2_session_id, 20); p += 20;
5056 memcpy(sigdata+p, ssh->pktout.data + 5,
51470298 5057 ssh->pktout.length - 5);
dda87a28 5058 p += ssh->pktout.length - 5;
5059 assert(p == sigdata_len);
d8baa528 5060 sigblob = key->alg->sign(key->data, (char *)sigdata,
1dd353b5 5061 sigdata_len, &sigblob_len);
51470298 5062 ssh2_add_sigblob(ssh, pkblob, pkblob_len,
1dd353b5 5063 sigblob, sigblob_len);
5064 sfree(pkblob);
5065 sfree(sigblob);
1408a877 5066 sfree(sigdata);
5067
51470298 5068 ssh2_pkt_send(ssh);
5069 s->type = AUTH_TYPE_PUBLICKEY;
1408a877 5070 }
51470298 5071 } else if (s->method == AUTH_PASSWORD) {
65a22376 5072 /*
1408a877 5073 * We send the password packet lumped tightly together with
5074 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
5075 * string long enough to make the total length of the two
5076 * packets constant. This should ensure that a passive
5077 * listener doing traffic analyis can't work out the length
5078 * of the password.
5079 *
5080 * For this to work, we need an assumption about the
5081 * maximum length of the password packet. I think 256 is
5082 * pretty conservative. Anyone using a password longer than
5083 * that probably doesn't have much to worry about from
5084 * people who find out how long their password is!
65a22376 5085 */
51470298 5086 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
5087 ssh2_pkt_addstring(ssh, s->username);
5088 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
5089 ssh2_pkt_addstring(ssh, "password");
5090 ssh2_pkt_addbool(ssh, FALSE);
5091 ssh2_pkt_addstring(ssh, s->password);
1409c1b3 5092 memset(s->password, 0, sizeof(s->password));
51470298 5093 ssh2_pkt_defer(ssh);
65a22376 5094 /*
1408a877 5095 * We'll include a string that's an exact multiple of the
5096 * cipher block size. If the cipher is NULL for some
5097 * reason, we don't do this trick at all because we gain
5098 * nothing by it.
65a22376 5099 */
51470298 5100 if (ssh->cscipher) {
32874aea 5101 int stringlen, i;
5102
51470298 5103 stringlen = (256 - ssh->deferred_len);
5104 stringlen += ssh->cscipher->blksize - 1;
5105 stringlen -= (stringlen % ssh->cscipher->blksize);
5106 if (ssh->cscomp) {
32874aea 5107 /*
5108 * Temporarily disable actual compression,
5109 * so we can guarantee to get this string
5110 * exactly the length we want it. The
5111 * compression-disabling routine should
5112 * return an integer indicating how many
5113 * bytes we should adjust our string length
5114 * by.
5115 */
5366aed8 5116 stringlen -=
5117 ssh->cscomp->disable_compression(ssh->cs_comp_ctx);
32874aea 5118 }
51470298 5119 ssh2_pkt_init(ssh, SSH2_MSG_IGNORE);
5120 ssh2_pkt_addstring_start(ssh);
6e9e9520 5121 for (i = 0; i < stringlen; i++) {
32874aea 5122 char c = (char) random_byte();
51470298 5123 ssh2_pkt_addstring_data(ssh, &c, 1);
65a22376 5124 }
51470298 5125 ssh2_pkt_defer(ssh);
65a22376 5126 }
51470298 5127 ssh_pkt_defersend(ssh);
0d43337a 5128 logevent("Sent password");
51470298 5129 s->type = AUTH_TYPE_PASSWORD;
5130 } else if (s->method == AUTH_KEYBOARD_INTERACTIVE) {
5131 if (s->curr_prompt == 0) {
5132 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_INFO_RESPONSE);
5133 ssh2_pkt_adduint32(ssh, s->num_prompts);
45068b27 5134 }
51470298 5135 if (s->need_pw) { /* only add pw if we just got one! */
5136 ssh2_pkt_addstring(ssh, s->password);
5137 memset(s->password, 0, sizeof(s->password));
5138 s->curr_prompt++;
45068b27 5139 }
51470298 5140 if (s->curr_prompt >= s->num_prompts) {
5141 ssh2_pkt_send(ssh);
45068b27 5142 } else {
5143 /*
5144 * If there are prompts remaining, we set
5145 * `gotit' so that we won't attempt to get
5146 * another packet. Then we go back round the
5147 * loop and will end up retrieving another
5148 * prompt out of the existing packet. Funky or
5149 * what?
5150 */
51470298 5151 s->gotit = TRUE;
45068b27 5152 }
51470298 5153 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
1408a877 5154 } else {
51470298 5155 c_write_str(ssh, "No supported authentication methods"
5156 " left to try!\r\n");
5157 logevent("No supported authentications offered."
5158 " Disconnecting");
5159 ssh2_pkt_init(ssh, SSH2_MSG_DISCONNECT);
5160 ssh2_pkt_adduint32(ssh, SSH2_DISCONNECT_BY_APPLICATION);
5161 ssh2_pkt_addstring(ssh, "No supported authentication"
5162 " methods available");
5163 ssh2_pkt_addstring(ssh, "en"); /* language tag */
5164 ssh2_pkt_send(ssh);
3bb2f322 5165 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 5166 crStopV;
65a22376 5167 }
65a22376 5168 }
51470298 5169 } while (!s->we_are_in);
7cca0d81 5170
5171 /*
5172 * Now we're authenticated for the connection protocol. The
5173 * connection protocol will automatically have started at this
5174 * point; there's no need to send SERVICE_REQUEST.
5175 */
5176
5177 /*
5178 * So now create a channel with a session in it.
5179 */
51470298 5180 ssh->channels = newtree234(ssh_channelcmp);
3d88e64d 5181 ssh->mainchan = snew(struct ssh_channel);
51470298 5182 ssh->mainchan->ssh = ssh;
5183 ssh->mainchan->localid = alloc_channel_id(ssh);
5184 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_OPEN);
5185 ssh2_pkt_addstring(ssh, "session");
5186 ssh2_pkt_adduint32(ssh, ssh->mainchan->localid);
5187 ssh->mainchan->v.v2.locwindow = OUR_V2_WINSIZE;
5188 ssh2_pkt_adduint32(ssh, ssh->mainchan->v.v2.locwindow);/* our window size */
5189 ssh2_pkt_adduint32(ssh, 0x4000UL); /* our max pkt size */
5190 ssh2_pkt_send(ssh);
7cca0d81 5191 crWaitUntilV(ispkt);
51470298 5192 if (ssh->pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
6b5cf8b4 5193 bombout(("Server refused to open a session"));
7ffdbc1a 5194 crStopV;
32874aea 5195 /* FIXME: error data comes back in FAILURE packet */
7cca0d81 5196 }
51470298 5197 if (ssh2_pkt_getuint32(ssh) != ssh->mainchan->localid) {
6b5cf8b4 5198 bombout(("Server's channel confirmation cited wrong channel"));
7ffdbc1a 5199 crStopV;
7cca0d81 5200 }
51470298 5201 ssh->mainchan->remoteid = ssh2_pkt_getuint32(ssh);
5202 ssh->mainchan->type = CHAN_MAINSESSION;
5203 ssh->mainchan->closes = 0;
5204 ssh->mainchan->v.v2.remwindow = ssh2_pkt_getuint32(ssh);
5205 ssh->mainchan->v.v2.remmaxpkt = ssh2_pkt_getuint32(ssh);
5206 bufchain_init(&ssh->mainchan->v.v2.outbuffer);
5207 add234(ssh->channels, ssh->mainchan);
7cca0d81 5208 logevent("Opened channel for session");
5209
5210 /*
783415f8 5211 * Potentially enable X11 forwarding.
5212 */
86916870 5213 if (ssh->cfg.x11_forward) {
32874aea 5214 char proto[20], data[64];
5215 logevent("Requesting X11 forwarding");
302121de 5216 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
86916870 5217 data, sizeof(data), ssh->cfg.x11_auth);
5218 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
51470298 5219 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
5220 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
5221 ssh2_pkt_addstring(ssh, "x11-req");
5222 ssh2_pkt_addbool(ssh, 1); /* want reply */
5223 ssh2_pkt_addbool(ssh, 0); /* many connections */
5224 ssh2_pkt_addstring(ssh, proto);
5225 ssh2_pkt_addstring(ssh, data);
86916870 5226 ssh2_pkt_adduint32(ssh, x11_get_screen_number(ssh->cfg.x11_display));
51470298 5227 ssh2_pkt_send(ssh);
32874aea 5228
5229 do {
5230 crWaitUntilV(ispkt);
51470298 5231 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
5232 unsigned i = ssh2_pkt_getuint32(ssh);
32874aea 5233 struct ssh_channel *c;
51470298 5234 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5235 if (!c)
5236 continue; /* nonexistent channel */
51470298 5237 c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
32874aea 5238 }
51470298 5239 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
32874aea 5240
51470298 5241 if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
5242 if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 5243 bombout(("Unexpected response to X11 forwarding request:"
51470298 5244 " packet type %d", ssh->pktin.type));
7ffdbc1a 5245 crStopV;
32874aea 5246 }
5247 logevent("X11 forwarding refused");
5248 } else {
5249 logevent("X11 forwarding enabled");
51470298 5250 ssh->X11_fwd_enabled = TRUE;
32874aea 5251 }
783415f8 5252 }
5253
5254 /*
bc240b21 5255 * Enable port forwardings.
5256 */
5257 {
bc240b21 5258 char type;
5259 int n;
a4fc0d74 5260 int sport,dport,sserv,dserv;
6ee9b735 5261 char sports[256], dports[256], saddr[256], host[256];
bc240b21 5262
51470298 5263 ssh->rportfwds = newtree234(ssh_rportcmp_ssh2);
bc240b21 5264 /* Add port forwardings. */
86916870 5265 ssh->portfwd_strptr = ssh->cfg.portfwd;
51470298 5266 while (*ssh->portfwd_strptr) {
5267 type = *ssh->portfwd_strptr++;
6ee9b735 5268 saddr[0] = '\0';
bc240b21 5269 n = 0;
6ee9b735 5270 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != '\t') {
5271 if (*ssh->portfwd_strptr == ':') {
5272 /*
5273 * We've seen a colon in the middle of the
5274 * source port number. This means that
5275 * everything we've seen until now is the
5276 * source _address_, so we'll move it into
5277 * saddr and start sports from the beginning
5278 * again.
5279 */
5280 ssh->portfwd_strptr++;
5281 sports[n] = '\0';
5282 strcpy(saddr, sports);
5283 n = 0;
5284 }
5285 if (n < 255) sports[n++] = *ssh->portfwd_strptr++;
5286 }
bc240b21 5287 sports[n] = 0;
820ebe3b 5288 if (type != 'D') {
5289 if (*ssh->portfwd_strptr == '\t')
5290 ssh->portfwd_strptr++;
5291 n = 0;
5292 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != ':') {
5293 if (n < 255) host[n++] = *ssh->portfwd_strptr++;
5294 }
5295 host[n] = 0;
5296 if (*ssh->portfwd_strptr == ':')
5297 ssh->portfwd_strptr++;
5298 n = 0;
5299 while (*ssh->portfwd_strptr) {
5300 if (n < 255) dports[n++] = *ssh->portfwd_strptr++;
5301 }
5302 dports[n] = 0;
51470298 5303 ssh->portfwd_strptr++;
820ebe3b 5304 dport = atoi(dports);
5305 dserv = 0;
5306 if (dport == 0) {
5307 dserv = 1;
5308 dport = net_service_lookup(dports);
5309 if (!dport) {
5310 logeventf(ssh, "Service lookup failed for destination"
5311 " port \"%s\"", dports);
5312 }
a4fc0d74 5313 }
820ebe3b 5314 } else {
5315 while (*ssh->portfwd_strptr) ssh->portfwd_strptr++;
7ffdbc1a 5316 dport = dserv = -1;
a4fc0d74 5317 }
bc240b21 5318 sport = atoi(sports);
a4fc0d74 5319 sserv = 0;
5320 if (sport == 0) {
5321 sserv = 1;
68a49acb 5322 sport = net_service_lookup(sports);
5323 if (!sport) {
57356d63 5324 logeventf(ssh, "Service lookup failed for source"
5325 " port \"%s\"", sports);
a4fc0d74 5326 }
5327 }
bc240b21 5328 if (sport && dport) {
5329 if (type == 'L') {
6ee9b735 5330 pfd_addforward(host, dport, *saddr ? saddr : NULL,
e8fa8f62 5331 sport, ssh, &ssh->cfg);
6ee9b735 5332 logeventf(ssh, "Local port %.*s%.*s%.*s%.*s%d%.*s"
5333 " forwarding to %s:%.*s%.*s%d%.*s",
5334 (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
5335 (int)(*saddr?1:0), ":",
57356d63 5336 (int)(sserv ? strlen(sports) : 0), sports,
5337 sserv, "(", sport, sserv, ")",
5338 host,
5339 (int)(dserv ? strlen(dports) : 0), dports,
5340 dserv, "(", dport, dserv, ")");
820ebe3b 5341 } else if (type == 'D') {
5342 pfd_addforward(NULL, -1, *saddr ? saddr : NULL,
5343 sport, ssh, &ssh->cfg);
5344 logeventf(ssh, "Local port %.*s%.*s%.*s%.*s%d%.*s"
5345 " doing SOCKS dynamic forwarding",
5346 (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
5347 (int)(*saddr?1:0), ":",
5348 (int)(sserv ? strlen(sports) : 0), sports,
5349 sserv, "(", sport, sserv, ")");
bc240b21 5350 } else {
5351 struct ssh_rportfwd *pf;
3d88e64d 5352 pf = snew(struct ssh_rportfwd);
bc240b21 5353 strcpy(pf->dhost, host);
5354 pf->dport = dport;
5355 pf->sport = sport;
51470298 5356 if (add234(ssh->rportfwds, pf) != pf) {
57356d63 5357 logeventf(ssh, "Duplicate remote port forwarding"
5358 " to %s:%d", host, dport);
bc240b21 5359 sfree(pf);
5360 } else {
6ee9b735 5361 logeventf(ssh, "Requesting remote port "
5362 "%.*s%.*s%.*s%.*s%d%.*s"
57356d63 5363 " forward to %s:%.*s%.*s%d%.*s",
6ee9b735 5364 (int)(*saddr?strlen(saddr):0),
5365 *saddr?saddr:NULL,
5366 (int)(*saddr?1:0), ":",
57356d63 5367 (int)(sserv ? strlen(sports) : 0), sports,
5368 sserv, "(", sport, sserv, ")",
5369 host,
5370 (int)(dserv ? strlen(dports) : 0), dports,
5371 dserv, "(", dport, dserv, ")");
51470298 5372 ssh2_pkt_init(ssh, SSH2_MSG_GLOBAL_REQUEST);
5373 ssh2_pkt_addstring(ssh, "tcpip-forward");
5374 ssh2_pkt_addbool(ssh, 1);/* want reply */
6ee9b735 5375 if (*saddr)
5376 ssh2_pkt_addstring(ssh, saddr);
86916870 5377 if (ssh->cfg.rport_acceptall)
51470298 5378 ssh2_pkt_addstring(ssh, "0.0.0.0");
beefa433 5379 else
51470298 5380 ssh2_pkt_addstring(ssh, "127.0.0.1");
5381 ssh2_pkt_adduint32(ssh, sport);
5382 ssh2_pkt_send(ssh);
bc240b21 5383
5384 do {
5385 crWaitUntilV(ispkt);
51470298 5386 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
5387 unsigned i = ssh2_pkt_getuint32(ssh);
bc240b21 5388 struct ssh_channel *c;
51470298 5389 c = find234(ssh->channels, &i, ssh_channelfind);
bc240b21 5390 if (!c)
5391 continue;/* nonexistent channel */
51470298 5392 c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
bc240b21 5393 }
51470298 5394 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
bc240b21 5395
51470298 5396 if (ssh->pktin.type != SSH2_MSG_REQUEST_SUCCESS) {
5397 if (ssh->pktin.type != SSH2_MSG_REQUEST_FAILURE) {
6b5cf8b4 5398 bombout(("Unexpected response to port "
c9886e66 5399 "forwarding request: packet type %d",
51470298 5400 ssh->pktin.type));
7ffdbc1a 5401 crStopV;
bc240b21 5402 }
5403 logevent("Server refused this port forwarding");
5404 } else {
5405 logevent("Remote port forwarding enabled");
5406 }
5407 }
5408 }
5409 }
5410 }
5411 }
5412
5413 /*
36c2a3e9 5414 * Potentially enable agent forwarding.
5415 */
86916870 5416 if (ssh->cfg.agentfwd && agent_exists()) {
32874aea 5417 logevent("Requesting OpenSSH-style agent forwarding");
51470298 5418 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
5419 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
5420 ssh2_pkt_addstring(ssh, "auth-agent-req@openssh.com");
5421 ssh2_pkt_addbool(ssh, 1); /* want reply */
5422 ssh2_pkt_send(ssh);
32874aea 5423
5424 do {
5425 crWaitUntilV(ispkt);
51470298 5426 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
5427 unsigned i = ssh2_pkt_getuint32(ssh);
32874aea 5428 struct ssh_channel *c;
51470298 5429 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5430 if (!c)
5431 continue; /* nonexistent channel */
51470298 5432 c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
32874aea 5433 }
51470298 5434 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
32874aea 5435
51470298 5436 if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
5437 if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 5438 bombout(("Unexpected response to agent forwarding request:"
51470298 5439 " packet type %d", ssh->pktin.type));
7ffdbc1a 5440 crStopV;
32874aea 5441 }
5442 logevent("Agent forwarding refused");
5443 } else {
5444 logevent("Agent forwarding enabled");
51470298 5445 ssh->agentfwd_enabled = TRUE;
32874aea 5446 }
36c2a3e9 5447 }
5448
5449 /*
7cca0d81 5450 * Now allocate a pty for the session.
5451 */
86916870 5452 if (!ssh->cfg.nopty) {
51470298 5453 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
5454 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid); /* recipient channel */
5455 ssh2_pkt_addstring(ssh, "pty-req");
5456 ssh2_pkt_addbool(ssh, 1); /* want reply */
86916870 5457 ssh2_pkt_addstring(ssh, ssh->cfg.termtype);
51470298 5458 ssh2_pkt_adduint32(ssh, ssh->term_width);
5459 ssh2_pkt_adduint32(ssh, ssh->term_height);
5460 ssh2_pkt_adduint32(ssh, 0); /* pixel width */
5461 ssh2_pkt_adduint32(ssh, 0); /* pixel height */
5462 ssh2_pkt_addstring_start(ssh);
5463 ssh2_pkt_addstring_data(ssh, "\0", 1); /* TTY_OP_END, no special options */
5464 ssh2_pkt_send(ssh);
5465 ssh->state = SSH_STATE_INTERMED;
32874aea 5466
5467 do {
5468 crWaitUntilV(ispkt);
51470298 5469 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
5470 unsigned i = ssh2_pkt_getuint32(ssh);
32874aea 5471 struct ssh_channel *c;
51470298 5472 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5473 if (!c)
5474 continue; /* nonexistent channel */
51470298 5475 c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
32874aea 5476 }
51470298 5477 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
32874aea 5478
51470298 5479 if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
5480 if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 5481 bombout(("Unexpected response to pty request:"
51470298 5482 " packet type %d", ssh->pktin.type));
7ffdbc1a 5483 crStopV;
32874aea 5484 }
51470298 5485 c_write_str(ssh, "Server refused to allocate pty\r\n");
5486 ssh->editing = ssh->echoing = 1;
32874aea 5487 } else {
5488 logevent("Allocated pty");
5489 }
0965bee0 5490 } else {
51470298 5491 ssh->editing = ssh->echoing = 1;
7cca0d81 5492 }
5493
5494 /*
fd5e5847 5495 * Start a shell or a remote command. We may have to attempt
5496 * this twice if the config data has provided a second choice
5497 * of command.
7cca0d81 5498 */
fd5e5847 5499 while (1) {
5500 int subsys;
5501 char *cmd;
5502
51470298 5503 if (ssh->fallback_cmd) {
86916870 5504 subsys = ssh->cfg.ssh_subsys2;
5505 cmd = ssh->cfg.remote_cmd_ptr2;
fd5e5847 5506 } else {
86916870 5507 subsys = ssh->cfg.ssh_subsys;
5508 cmd = ssh->cfg.remote_cmd_ptr;
fd5e5847 5509 }
5510
51470298 5511 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
5512 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid); /* recipient channel */
fd5e5847 5513 if (subsys) {
51470298 5514 ssh2_pkt_addstring(ssh, "subsystem");
5515 ssh2_pkt_addbool(ssh, 1); /* want reply */
5516 ssh2_pkt_addstring(ssh, cmd);
fd5e5847 5517 } else if (*cmd) {
51470298 5518 ssh2_pkt_addstring(ssh, "exec");
5519 ssh2_pkt_addbool(ssh, 1); /* want reply */
5520 ssh2_pkt_addstring(ssh, cmd);
fd5e5847 5521 } else {
51470298 5522 ssh2_pkt_addstring(ssh, "shell");
5523 ssh2_pkt_addbool(ssh, 1); /* want reply */
32874aea 5524 }
51470298 5525 ssh2_pkt_send(ssh);
fd5e5847 5526 do {
5527 crWaitUntilV(ispkt);
51470298 5528 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
5529 unsigned i = ssh2_pkt_getuint32(ssh);
fd5e5847 5530 struct ssh_channel *c;
51470298 5531 c = find234(ssh->channels, &i, ssh_channelfind);
fd5e5847 5532 if (!c)
5533 continue; /* nonexistent channel */
51470298 5534 c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
fd5e5847 5535 }
51470298 5536 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
5537 if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
5538 if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 5539 bombout(("Unexpected response to shell/command request:"
51470298 5540 " packet type %d", ssh->pktin.type));
7ffdbc1a 5541 crStopV;
fd5e5847 5542 }
5543 /*
5544 * We failed to start the command. If this is the
5545 * fallback command, we really are finished; if it's
5546 * not, and if the fallback command exists, try falling
5547 * back to it before complaining.
5548 */
86916870 5549 if (!ssh->fallback_cmd && ssh->cfg.remote_cmd_ptr2 != NULL) {
fd5e5847 5550 logevent("Primary command failed; attempting fallback");
51470298 5551 ssh->fallback_cmd = TRUE;
fd5e5847 5552 continue;
5553 }
6b5cf8b4 5554 bombout(("Server refused to start a shell/command"));
7ffdbc1a 5555 crStopV;
fd5e5847 5556 } else {
5557 logevent("Started a shell/command");
32874aea 5558 }
fd5e5847 5559 break;
7cca0d81 5560 }
5561
51470298 5562 ssh->state = SSH_STATE_SESSION;
5563 if (ssh->size_needed)
5564 ssh_size(ssh, ssh->term_width, ssh->term_height);
5565 if (ssh->eof_needed)
5566 ssh_special(ssh, TS_EOF);
6e48c3fe 5567
7cca0d81 5568 /*
5569 * Transfer data!
5570 */
b9d7bcad 5571 if (ssh->ldisc)
5572 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
51470298 5573 ssh->send_ok = 1;
7cca0d81 5574 while (1) {
e5574168 5575 crReturnV;
51470298 5576 s->try_send = FALSE;
7cca0d81 5577 if (ispkt) {
51470298 5578 if (ssh->pktin.type == SSH2_MSG_CHANNEL_DATA ||
5579 ssh->pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
32874aea 5580 char *data;
5581 int length;
51470298 5582 unsigned i = ssh2_pkt_getuint32(ssh);
32874aea 5583 struct ssh_channel *c;
51470298 5584 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5585 if (!c)
5586 continue; /* nonexistent channel */
51470298 5587 if (ssh->pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
5588 ssh2_pkt_getuint32(ssh) != SSH2_EXTENDED_DATA_STDERR)
32874aea 5589 continue; /* extended but not stderr */
51470298 5590 ssh2_pkt_getstring(ssh, &data, &length);
32874aea 5591 if (data) {
7ffdbc1a 5592 int bufsize = 0;
5471d09a 5593 c->v.v2.locwindow -= length;
32874aea 5594 switch (c->type) {
5595 case CHAN_MAINSESSION:
5471d09a 5596 bufsize =
51470298 5597 from_backend(ssh->frontend, ssh->pktin.type ==
5471d09a 5598 SSH2_MSG_CHANNEL_EXTENDED_DATA,
5599 data, length);
32874aea 5600 break;
5601 case CHAN_X11:
5471d09a 5602 bufsize = x11_send(c->u.x11.s, data, length);
32874aea 5603 break;
d74d141c 5604 case CHAN_SOCKDATA:
5471d09a 5605 bufsize = pfd_send(c->u.pfd.s, data, length);
bc240b21 5606 break;
36c2a3e9 5607 case CHAN_AGENT:
32874aea 5608 while (length > 0) {
5609 if (c->u.a.lensofar < 4) {
5610 int l = min(4 - c->u.a.lensofar, length);
5611 memcpy(c->u.a.msglen + c->u.a.lensofar,
5612 data, l);
5613 data += l;
5614 length -= l;
5615 c->u.a.lensofar += l;
5616 }
5617 if (c->u.a.lensofar == 4) {
5618 c->u.a.totallen =
5619 4 + GET_32BIT(c->u.a.msglen);
3d88e64d 5620 c->u.a.message = snewn(c->u.a.totallen,
5621 unsigned char);
32874aea 5622 memcpy(c->u.a.message, c->u.a.msglen, 4);
5623 }
5624 if (c->u.a.lensofar >= 4 && length > 0) {
5625 int l =
5626 min(c->u.a.totallen - c->u.a.lensofar,
5627 length);
5628 memcpy(c->u.a.message + c->u.a.lensofar,
5629 data, l);
5630 data += l;
5631 length -= l;
5632 c->u.a.lensofar += l;
5633 }
5634 if (c->u.a.lensofar == c->u.a.totallen) {
5635 void *reply, *sentreply;
5636 int replylen;
5637 agent_query(c->u.a.message,
5638 c->u.a.totallen, &reply,
5639 &replylen);
5640 if (reply)
5641 sentreply = reply;
5642 else {
5643 /* Fake SSH_AGENT_FAILURE. */
5644 sentreply = "\0\0\0\1\5";
5645 replylen = 5;
5646 }
51470298 5647 ssh2_add_channel_data(c, sentreply, replylen);
5648 s->try_send = TRUE;
32874aea 5649 if (reply)
5650 sfree(reply);
5651 sfree(c->u.a.message);
5652 c->u.a.lensofar = 0;
5653 }
5654 }
5471d09a 5655 bufsize = 0;
32874aea 5656 break;
5657 }
5658 /*
5471d09a 5659 * If we are not buffering too much data,
5660 * enlarge the window again at the remote side.
32874aea 5661 */
5471d09a 5662 if (bufsize < OUR_V2_WINSIZE)
5663 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
32874aea 5664 }
51470298 5665 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_EOF) {
5666 unsigned i = ssh2_pkt_getuint32(ssh);
32874aea 5667 struct ssh_channel *c;
5668
51470298 5669 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5670 if (!c)
5671 continue; /* nonexistent channel */
5672
5673 if (c->type == CHAN_X11) {
5674 /*
5675 * Remote EOF on an X11 channel means we should
5676 * wrap up and close the channel ourselves.
5677 */
5678 x11_close(c->u.x11.s);
5679 sshfwd_close(c);
5680 } else if (c->type == CHAN_AGENT) {
36c2a3e9 5681 sshfwd_close(c);
d74d141c 5682 } else if (c->type == CHAN_SOCKDATA) {
bc240b21 5683 pfd_close(c->u.pfd.s);
5684 sshfwd_close(c);
36c2a3e9 5685 }
51470298 5686 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_CLOSE) {
5687 unsigned i = ssh2_pkt_getuint32(ssh);
32874aea 5688 struct ssh_channel *c;
5689
51470298 5690 c = find234(ssh->channels, &i, ssh_channelfind);
d0d844c1 5691 if (!c || ((int)c->remoteid) == -1) {
6b5cf8b4 5692 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
d0d844c1 5693 c ? "half-open" : "nonexistent", i));
7ffdbc1a 5694 crStopV;
d0d844c1 5695 }
32874aea 5696 /* Do pre-close processing on the channel. */
5697 switch (c->type) {
5698 case CHAN_MAINSESSION:
5699 break; /* nothing to see here, move along */
5700 case CHAN_X11:
92f157bd 5701 if (c->u.x11.s != NULL)
5702 x11_close(c->u.x11.s);
5703 sshfwd_close(c);
32874aea 5704 break;
5705 case CHAN_AGENT:
92f157bd 5706 sshfwd_close(c);
32874aea 5707 break;
d74d141c 5708 case CHAN_SOCKDATA:
92f157bd 5709 if (c->u.pfd.s != NULL)
5710 pfd_close(c->u.pfd.s);
5711 sshfwd_close(c);
bc240b21 5712 break;
32874aea 5713 }
92f157bd 5714 if (c->closes == 0) {
51470298 5715 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_CLOSE);
5716 ssh2_pkt_adduint32(ssh, c->remoteid);
5717 ssh2_pkt_send(ssh);
92f157bd 5718 }
51470298 5719 del234(ssh->channels, c);
5471d09a 5720 bufchain_clear(&c->v.v2.outbuffer);
32874aea 5721 sfree(c);
5722
5723 /*
5724 * See if that was the last channel left open.
5725 */
51470298 5726 if (count234(ssh->channels) == 0) {
3bb2f322 5727 logevent("All channels closed. Disconnecting");
ca2914d1 5728#if 0
5729 /*
5730 * We used to send SSH_MSG_DISCONNECT here,
5731 * because I'd believed that _every_ conforming
5732 * SSH2 connection had to end with a disconnect
5733 * being sent by at least one side; apparently
5734 * I was wrong and it's perfectly OK to
5735 * unceremoniously slam the connection shut
5736 * when you're done, and indeed OpenSSH feels
5737 * this is more polite than sending a
5738 * DISCONNECT. So now we don't.
5739 */
51470298 5740 ssh2_pkt_init(ssh, SSH2_MSG_DISCONNECT);
5741 ssh2_pkt_adduint32(ssh, SSH2_DISCONNECT_BY_APPLICATION);
5742 ssh2_pkt_addstring(ssh, "All open channels closed");
5743 ssh2_pkt_addstring(ssh, "en"); /* language tag */
5744 ssh2_pkt_send(ssh);
ca2914d1 5745#endif
3bb2f322 5746 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 5747 crStopV;
32874aea 5748 }
5749 continue; /* remote sends close; ignore (FIXME) */
51470298 5750 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
5751 unsigned i = ssh2_pkt_getuint32(ssh);
32874aea 5752 struct ssh_channel *c;
51470298 5753 c = find234(ssh->channels, &i, ssh_channelfind);
a6253970 5754 if (!c || c->closes)
5755 continue; /* nonexistent or closing channel */
51470298 5756 c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
5757 s->try_send = TRUE;
5758 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
5759 unsigned i = ssh2_pkt_getuint32(ssh);
bc240b21 5760 struct ssh_channel *c;
51470298 5761 c = find234(ssh->channels, &i, ssh_channelfind);
bc240b21 5762 if (!c)
5763 continue; /* nonexistent channel */
5764 if (c->type != CHAN_SOCKDATA_DORMANT)
5765 continue; /* dunno why they're confirming this */
51470298 5766 c->remoteid = ssh2_pkt_getuint32(ssh);
bc240b21 5767 c->type = CHAN_SOCKDATA;
51470298 5768 c->v.v2.remwindow = ssh2_pkt_getuint32(ssh);
5769 c->v.v2.remmaxpkt = ssh2_pkt_getuint32(ssh);
4ed34d25 5770 if (c->u.pfd.s)
5771 pfd_confirm(c->u.pfd.s);
5772 if (c->closes) {
5773 /*
5774 * We have a pending close on this channel,
5775 * which we decided on before the server acked
5776 * the channel open. So now we know the
5777 * remoteid, we can close it again.
5778 */
51470298 5779 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_CLOSE);
5780 ssh2_pkt_adduint32(ssh, c->remoteid);
5781 ssh2_pkt_send(ssh);
4ed34d25 5782 }
51470298 5783 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_OPEN_FAILURE) {
5784 unsigned i = ssh2_pkt_getuint32(ssh);
724cface 5785 struct ssh_channel *c;
51470298 5786 c = find234(ssh->channels, &i, ssh_channelfind);
724cface 5787 if (!c)
5788 continue; /* nonexistent channel */
5789 if (c->type != CHAN_SOCKDATA_DORMANT)
5790 continue; /* dunno why they're failing this */
5791
5792 logevent("Forwarded connection refused by server");
5793
5794 pfd_close(c->u.pfd.s);
5795
51470298 5796 del234(ssh->channels, c);
724cface 5797 sfree(c);
51470298 5798 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_REQUEST) {
ebb0a590 5799 unsigned localid;
5800 char *type;
5801 int typelen, want_reply;
5802 struct ssh_channel *c;
5803
51470298 5804 localid = ssh2_pkt_getuint32(ssh);
5805 ssh2_pkt_getstring(ssh, &type, &typelen);
5806 want_reply = ssh2_pkt_getbool(ssh);
ebb0a590 5807
5808 /*
5809 * First, check that the channel exists. Otherwise,
5810 * we can instantly disconnect with a rude message.
5811 */
51470298 5812 c = find234(ssh->channels, &localid, ssh_channelfind);
ebb0a590 5813 if (!c) {
5814 char buf[80];
5815 sprintf(buf, "Received channel request for nonexistent"
5816 " channel %d", localid);
5817 logevent(buf);
51470298 5818 ssh2_pkt_init(ssh, SSH2_MSG_DISCONNECT);
5819 ssh2_pkt_adduint32(ssh, SSH2_DISCONNECT_BY_APPLICATION);
5820 ssh2_pkt_addstring(ssh, buf);
5821 ssh2_pkt_addstring(ssh, "en"); /* language tag */
5822 ssh2_pkt_send(ssh);
6b5cf8b4 5823 connection_fatal(ssh->frontend, "%s", buf);
3bb2f322 5824 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 5825 crStopV;
ebb0a590 5826 }
5827
5828 /*
d8d6c7e5 5829 * Having got the channel number, we now look at
5830 * the request type string to see if it's something
5831 * we recognise.
ebb0a590 5832 */
d8d6c7e5 5833 if (typelen == 11 && !memcmp(type, "exit-status", 11) &&
51470298 5834 c == ssh->mainchan) {
d8d6c7e5 5835 /* We recognise "exit-status" on the primary channel. */
5836 char buf[100];
51470298 5837 ssh->exitcode = ssh2_pkt_getuint32(ssh);
d8d6c7e5 5838 sprintf(buf, "Server sent command exit status %d",
51470298 5839 ssh->exitcode);
d8d6c7e5 5840 logevent(buf);
5841 if (want_reply) {
51470298 5842 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_SUCCESS);
5843 ssh2_pkt_adduint32(ssh, c->remoteid);
5844 ssh2_pkt_send(ssh);
d8d6c7e5 5845 }
5846 } else {
5847 /*
5848 * This is a channel request we don't know
5849 * about, so we now either ignore the request
5850 * or respond with CHANNEL_FAILURE, depending
5851 * on want_reply.
5852 */
5853 if (want_reply) {
51470298 5854 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_FAILURE);
5855 ssh2_pkt_adduint32(ssh, c->remoteid);
5856 ssh2_pkt_send(ssh);
d8d6c7e5 5857 }
ebb0a590 5858 }
51470298 5859 } else if (ssh->pktin.type == SSH2_MSG_GLOBAL_REQUEST) {
697d4856 5860 char *type;
5861 int typelen, want_reply;
5862
51470298 5863 ssh2_pkt_getstring(ssh, &type, &typelen);
5864 want_reply = ssh2_pkt_getbool(ssh);
697d4856 5865
5866 /*
5867 * We currently don't support any global requests
5868 * at all, so we either ignore the request or
5869 * respond with REQUEST_FAILURE, depending on
5870 * want_reply.
5871 */
5872 if (want_reply) {
51470298 5873 ssh2_pkt_init(ssh, SSH2_MSG_REQUEST_FAILURE);
5874 ssh2_pkt_send(ssh);
697d4856 5875 }
51470298 5876 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_OPEN) {
32874aea 5877 char *type;
5878 int typelen;
b3ebaa28 5879 char *peeraddr;
5880 int peeraddrlen;
2e5b14c0 5881 int peerport;
32874aea 5882 char *error = NULL;
5883 struct ssh_channel *c;
bc240b21 5884 unsigned remid, winsize, pktsize;
51470298 5885 ssh2_pkt_getstring(ssh, &type, &typelen);
3d88e64d 5886 c = snew(struct ssh_channel);
51470298 5887 c->ssh = ssh;
32874aea 5888
51470298 5889 remid = ssh2_pkt_getuint32(ssh);
5890 winsize = ssh2_pkt_getuint32(ssh);
5891 pktsize = ssh2_pkt_getuint32(ssh);
bc240b21 5892
32874aea 5893 if (typelen == 3 && !memcmp(type, "x11", 3)) {
df85f78b 5894 char *addrstr;
5895
5896 ssh2_pkt_getstring(ssh, &peeraddr, &peeraddrlen);
5897 addrstr = snewn(peeraddrlen+1, char);
b3ebaa28 5898 memcpy(addrstr, peeraddr, peeraddrlen);
5899 peeraddr[peeraddrlen] = '\0';
2e5b14c0 5900 peerport = ssh2_pkt_getuint32(ssh);
b3ebaa28 5901
51470298 5902 if (!ssh->X11_fwd_enabled)
32874aea 5903 error = "X11 forwarding is not enabled";
86916870 5904 else if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
2e5b14c0 5905 ssh->x11auth, addrstr, peerport,
e8fa8f62 5906 &ssh->cfg) != NULL) {
32874aea 5907 error = "Unable to open an X11 connection";
5908 } else {
5909 c->type = CHAN_X11;
5910 }
b3ebaa28 5911
5912 sfree(addrstr);
bc240b21 5913 } else if (typelen == 15 &&
5914 !memcmp(type, "forwarded-tcpip", 15)) {
5915 struct ssh_rportfwd pf, *realpf;
5916 char *dummy;
5917 int dummylen;
51470298 5918 ssh2_pkt_getstring(ssh, &dummy, &dummylen);/* skip address */
5919 pf.sport = ssh2_pkt_getuint32(ssh);
2e5b14c0 5920 ssh2_pkt_getstring(ssh, &peeraddr, &peeraddrlen);
5921 peerport = ssh2_pkt_getuint32(ssh);
51470298 5922 realpf = find234(ssh->rportfwds, &pf, NULL);
bc240b21 5923 if (realpf == NULL) {
5924 error = "Remote port is not recognised";
5925 } else {
5926 char *e = pfd_newconnect(&c->u.pfd.s, realpf->dhost,
e8fa8f62 5927 realpf->dport, c, &ssh->cfg);
57356d63 5928 logeventf(ssh, "Received remote port open request"
5929 " for %s:%d", realpf->dhost, realpf->dport);
bc240b21 5930 if (e != NULL) {
57356d63 5931 logeventf(ssh, "Port open failed: %s", e);
bc240b21 5932 error = "Port open failed";
5933 } else {
5934 logevent("Forwarded port opened successfully");
5935 c->type = CHAN_SOCKDATA;
5936 }
5937 }
32874aea 5938 } else if (typelen == 22 &&
36c2a3e9 5939 !memcmp(type, "auth-agent@openssh.com", 3)) {
51470298 5940 if (!ssh->agentfwd_enabled)
32874aea 5941 error = "Agent forwarding is not enabled";
36c2a3e9 5942 else {
32874aea 5943 c->type = CHAN_AGENT; /* identify channel type */
36c2a3e9 5944 c->u.a.lensofar = 0;
32874aea 5945 }
5946 } else {
5947 error = "Unsupported channel type requested";
5948 }
5949
bc240b21 5950 c->remoteid = remid;
32874aea 5951 if (error) {
51470298 5952 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_OPEN_FAILURE);
5953 ssh2_pkt_adduint32(ssh, c->remoteid);
5954 ssh2_pkt_adduint32(ssh, SSH2_OPEN_CONNECT_FAILED);
5955 ssh2_pkt_addstring(ssh, error);
5956 ssh2_pkt_addstring(ssh, "en"); /* language tag */
5957 ssh2_pkt_send(ssh);
32874aea 5958 sfree(c);
5959 } else {
51470298 5960 c->localid = alloc_channel_id(ssh);
32874aea 5961 c->closes = 0;
5471d09a 5962 c->v.v2.locwindow = OUR_V2_WINSIZE;
5963 c->v.v2.remwindow = winsize;
5964 c->v.v2.remmaxpkt = pktsize;
5965 bufchain_init(&c->v.v2.outbuffer);
51470298 5966 add234(ssh->channels, c);
5967 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
5968 ssh2_pkt_adduint32(ssh, c->remoteid);
5969 ssh2_pkt_adduint32(ssh, c->localid);
5970 ssh2_pkt_adduint32(ssh, c->v.v2.locwindow);
5971 ssh2_pkt_adduint32(ssh, 0x4000UL); /* our max pkt size */
5972 ssh2_pkt_send(ssh);
32874aea 5973 }
7cca0d81 5974 } else {
6b5cf8b4 5975 bombout(("Strange packet received: type %d", ssh->pktin.type));
7ffdbc1a 5976 crStopV;
7cca0d81 5977 }
5978 } else {
32874aea 5979 /*
5980 * We have spare data. Add it to the channel buffer.
5981 */
d8baa528 5982 ssh2_add_channel_data(ssh->mainchan, (char *)in, inlen);
51470298 5983 s->try_send = TRUE;
32874aea 5984 }
51470298 5985 if (s->try_send) {
32874aea 5986 int i;
5987 struct ssh_channel *c;
5988 /*
5989 * Try to send data on all channels if we can.
5990 */
51470298 5991 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
a6253970 5992 int bufsize;
5993 if (c->closes)
5994 continue; /* don't send on closing channels */
5995 bufsize = ssh2_try_send(c);
5471d09a 5996 if (bufsize == 0) {
5997 switch (c->type) {
5998 case CHAN_MAINSESSION:
5999 /* stdin need not receive an unthrottle
6000 * notification since it will be polled */
6001 break;
6002 case CHAN_X11:
6003 x11_unthrottle(c->u.x11.s);
6004 break;
6005 case CHAN_AGENT:
6006 /* agent sockets are request/response and need no
6007 * buffer management */
6008 break;
6009 case CHAN_SOCKDATA:
6010 pfd_unthrottle(c->u.pfd.s);
6011 break;
6012 }
6013 }
6014 }
7cca0d81 6015 }
e5574168 6016 }
6017
6018 crFinishV;
6019}
6020
6021/*
7cca0d81 6022 * Handle the top-level SSH2 protocol.
6023 */
51470298 6024static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
7cca0d81 6025{
51470298 6026 if (do_ssh2_transport(ssh, in, inlen, ispkt) == 0)
32874aea 6027 return;
51470298 6028 do_ssh2_authconn(ssh, in, inlen, ispkt);
7cca0d81 6029}
6030
6031/*
8df7a775 6032 * Called to set up the connection.
374330e2 6033 *
6034 * Returns an error message, or NULL on success.
374330e2 6035 */
51470298 6036static char *ssh_init(void *frontend_handle, void **backend_handle,
86916870 6037 Config *cfg,
887035a5 6038 char *host, int port, char **realhost, int nodelay)
32874aea 6039{
fb09bf1c 6040 char *p;
51470298 6041 Ssh ssh;
6042
3d88e64d 6043 ssh = snew(struct ssh_tag);
86916870 6044 ssh->cfg = *cfg; /* STRUCTURE COPY */
125105d1 6045 ssh->version = 0; /* when not ready yet */
51470298 6046 ssh->s = NULL;
6047 ssh->cipher = NULL;
371e569c 6048 ssh->v1_cipher_ctx = NULL;
0183b242 6049 ssh->crcda_ctx = NULL;
51470298 6050 ssh->cscipher = NULL;
371e569c 6051 ssh->cs_cipher_ctx = NULL;
51470298 6052 ssh->sccipher = NULL;
371e569c 6053 ssh->sc_cipher_ctx = NULL;
51470298 6054 ssh->csmac = NULL;
a8327734 6055 ssh->cs_mac_ctx = NULL;
51470298 6056 ssh->scmac = NULL;
e0e1a00d 6057 ssh->sc_mac_ctx = NULL;
51470298 6058 ssh->cscomp = NULL;
5366aed8 6059 ssh->cs_comp_ctx = NULL;
51470298 6060 ssh->sccomp = NULL;
5366aed8 6061 ssh->sc_comp_ctx = NULL;
51470298 6062 ssh->kex = NULL;
389aa499 6063 ssh->kex_ctx = NULL;
51470298 6064 ssh->hostkey = NULL;
6065 ssh->exitcode = -1;
6066 ssh->state = SSH_STATE_PREPACKET;
6067 ssh->size_needed = FALSE;
6068 ssh->eof_needed = FALSE;
b9d7bcad 6069 ssh->ldisc = NULL;
a8327734 6070 ssh->logctx = NULL;
51470298 6071 {
6072 static const struct Packet empty = { 0, 0, NULL, NULL, 0 };
6073 ssh->pktin = ssh->pktout = empty;
6074 }
6075 ssh->deferred_send_data = NULL;
6076 ssh->deferred_len = 0;
6077 ssh->deferred_size = 0;
6078 ssh->fallback_cmd = 0;
6079 ssh->pkt_ctx = 0;
302121de 6080 ssh->x11auth = NULL;
be738459 6081 ssh->v1_compressing = FALSE;
51470298 6082 ssh->v2_outgoing_sequence = 0;
6083 ssh->ssh1_rdpkt_crstate = 0;
6084 ssh->ssh2_rdpkt_crstate = 0;
6085 ssh->do_ssh_init_crstate = 0;
6086 ssh->ssh_gotdata_crstate = 0;
6087 ssh->ssh1_protocol_crstate = 0;
6088 ssh->do_ssh1_login_crstate = 0;
6089 ssh->do_ssh2_transport_crstate = 0;
6090 ssh->do_ssh2_authconn_crstate = 0;
6091 ssh->do_ssh_init_state = NULL;
6092 ssh->do_ssh1_login_state = NULL;
6093 ssh->do_ssh2_transport_state = NULL;
6094 ssh->do_ssh2_authconn_state = NULL;
6571dbfd 6095 ssh->mainchan = NULL;
968d2d92 6096 ssh->throttled_all = 0;
6097 ssh->v1_stdout_throttling = 0;
51470298 6098
6099 *backend_handle = ssh;
32874aea 6100
8f203108 6101#ifdef MSCRYPTOAPI
32874aea 6102 if (crypto_startup() == 0)
8f203108 6103 return "Microsoft high encryption pack not installed!";
6104#endif
374330e2 6105
51470298 6106 ssh->frontend = frontend_handle;
86916870 6107 ssh->term_width = ssh->cfg.width;
6108 ssh->term_height = ssh->cfg.height;
887035a5 6109
fabd1805 6110 ssh->channels = NULL;
6111 ssh->rportfwds = NULL;
6112
51470298 6113 ssh->send_ok = 0;
6114 ssh->editing = 0;
6115 ssh->echoing = 0;
6116 ssh->v1_throttle_count = 0;
6117 ssh->overall_bufsize = 0;
6118 ssh->fallback_cmd = 0;
8df7a775 6119
3648d4c5 6120 ssh->protocol = NULL;
6121
51470298 6122 p = connect_to_host(ssh, host, port, realhost, nodelay);
fb09bf1c 6123 if (p != NULL)
6124 return p;
374330e2 6125
374330e2 6126 return NULL;
6127}
6128
fabd1805 6129static void ssh_free(void *handle)
6130{
6131 Ssh ssh = (Ssh) handle;
6132 struct ssh_channel *c;
6133 struct ssh_rportfwd *pf;
6134
6135 if (ssh->v1_cipher_ctx)
6136 ssh->cipher->free_context(ssh->v1_cipher_ctx);
6137 if (ssh->cs_cipher_ctx)
6138 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
6139 if (ssh->sc_cipher_ctx)
6140 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
6141 if (ssh->cs_mac_ctx)
6142 ssh->csmac->free_context(ssh->cs_mac_ctx);
6143 if (ssh->sc_mac_ctx)
6144 ssh->scmac->free_context(ssh->sc_mac_ctx);
6145 if (ssh->cs_comp_ctx)
6146 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
6147 if (ssh->sc_comp_ctx)
6148 ssh->sccomp->compress_cleanup(ssh->sc_comp_ctx);
6149 if (ssh->kex_ctx)
6150 dh_cleanup(ssh->kex_ctx);
6151 sfree(ssh->savedhost);
6152
6153 if (ssh->channels) {
6154 while ((c = delpos234(ssh->channels, 0)) != NULL) {
6155 switch (c->type) {
6156 case CHAN_X11:
6157 if (c->u.x11.s != NULL)
6158 x11_close(c->u.x11.s);
6159 break;
6160 case CHAN_SOCKDATA:
6161 if (c->u.pfd.s != NULL)
6162 pfd_close(c->u.pfd.s);
6163 break;
6164 }
6165 sfree(c);
6166 }
6167 freetree234(ssh->channels);
6168 }
6169
6170 if (ssh->rportfwds) {
6171 while ((pf = delpos234(ssh->rportfwds, 0)) != NULL)
6172 sfree(pf);
6173 freetree234(ssh->rportfwds);
6174 }
6175 sfree(ssh->deferred_send_data);
6176 if (ssh->x11auth)
6177 x11_free_auth(ssh->x11auth);
6178 sfree(ssh->do_ssh_init_state);
6179 sfree(ssh->do_ssh1_login_state);
6180 sfree(ssh->do_ssh2_transport_state);
6181 sfree(ssh->do_ssh2_authconn_state);
6182
6183 if (ssh->s)
36f94d1f 6184 ssh_do_close(ssh);
fabd1805 6185 sfree(ssh);
6186}
6187
374330e2 6188/*
86916870 6189 * Reconfigure the SSH backend.
6190 *
6191 * Currently, this function does nothing very useful. In future,
6192 * however, we could do some handy things with it. For example, we
6193 * could make the port forwarding configurer active in the Change
6194 * Settings box, and this routine could close down existing
6195 * forwardings and open up new ones in response to changes.
6196 */
6197static void ssh_reconfig(void *handle, Config *cfg)
6198{
6199 Ssh ssh = (Ssh) handle;
6200 ssh->cfg = *cfg; /* STRUCTURE COPY */
6201}
6202
6203/*
374330e2 6204 * Called to send data down the Telnet connection.
6205 */
51470298 6206static int ssh_send(void *handle, char *buf, int len)
32874aea 6207{
51470298 6208 Ssh ssh = (Ssh) handle;
6209
6210 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
5471d09a 6211 return 0;
374330e2 6212
d8baa528 6213 ssh->protocol(ssh, (unsigned char *)buf, len, 0);
5471d09a 6214
51470298 6215 return ssh_sendbuffer(ssh);
5471d09a 6216}
6217
6218/*
6219 * Called to query the current amount of buffered stdin data.
6220 */
51470298 6221static int ssh_sendbuffer(void *handle)
5471d09a 6222{
51470298 6223 Ssh ssh = (Ssh) handle;
5471d09a 6224 int override_value;
6225
51470298 6226 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
5471d09a 6227 return 0;
6228
6229 /*
6230 * If the SSH socket itself has backed up, add the total backup
6231 * size on that to any individual buffer on the stdin channel.
6232 */
6233 override_value = 0;
51470298 6234 if (ssh->throttled_all)
6235 override_value = ssh->overall_bufsize;
5471d09a 6236
51470298 6237 if (ssh->version == 1) {
5471d09a 6238 return override_value;
51470298 6239 } else if (ssh->version == 2) {
6240 if (!ssh->mainchan || ssh->mainchan->closes > 0)
5471d09a 6241 return override_value;
6242 else
51470298 6243 return (override_value +
6244 bufchain_size(&ssh->mainchan->v.v2.outbuffer));
5471d09a 6245 }
6246
6247 return 0;
374330e2 6248}
6249
6250/*
6e48c3fe 6251 * Called to set the size of the window from SSH's POV.
374330e2 6252 */
51470298 6253static void ssh_size(void *handle, int width, int height)
32874aea 6254{
51470298 6255 Ssh ssh = (Ssh) handle;
6256
6257 ssh->term_width = width;
6258 ssh->term_height = height;
f278d6f8 6259
51470298 6260 switch (ssh->state) {
374330e2 6261 case SSH_STATE_BEFORE_SIZE:
3687d221 6262 case SSH_STATE_PREPACKET:
21248260 6263 case SSH_STATE_CLOSED:
374330e2 6264 break; /* do nothing */
6265 case SSH_STATE_INTERMED:
51470298 6266 ssh->size_needed = TRUE; /* buffer for later */
374330e2 6267 break;
6268 case SSH_STATE_SESSION:
86916870 6269 if (!ssh->cfg.nopty) {
51470298 6270 if (ssh->version == 1) {
6271 send_packet(ssh, SSH1_CMSG_WINDOW_SIZE,
6272 PKT_INT, ssh->term_height,
6273 PKT_INT, ssh->term_width,
32874aea 6274 PKT_INT, 0, PKT_INT, 0, PKT_END);
6275 } else {
51470298 6276 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
6277 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
6278 ssh2_pkt_addstring(ssh, "window-change");
6279 ssh2_pkt_addbool(ssh, 0);
6280 ssh2_pkt_adduint32(ssh, ssh->term_width);
6281 ssh2_pkt_adduint32(ssh, ssh->term_height);
6282 ssh2_pkt_adduint32(ssh, 0);
6283 ssh2_pkt_adduint32(ssh, 0);
6284 ssh2_pkt_send(ssh);
32874aea 6285 }
6286 }
6287 break;
374330e2 6288 }
6289}
6290
6291/*
125105d1 6292 * Return a list of the special codes that make sense in this
6293 * protocol.
6294 */
6295static const struct telnet_special *ssh_get_specials(void *handle)
6296{
6297 Ssh ssh = (Ssh) handle;
6298
6299 if (ssh->version == 1) {
6300 static const struct telnet_special ssh1_specials[] = {
6301 {"IGNORE message", TS_NOP},
6302 {NULL, 0}
6303 };
6304 return ssh1_specials;
6305 } else if (ssh->version == 2) {
6306 static const struct telnet_special ssh2_specials[] = {
6307 {"Break", TS_BRK},
6308 {"IGNORE message", TS_NOP},
6309 {NULL, 0}
6310 };
6311 return ssh2_specials;
6312 } else
6313 return NULL;
6314}
6315
6316/*
6abbf9e3 6317 * Send Telnet special codes. TS_EOF is useful for `plink', so you
6318 * can send an EOF and collect resulting output (e.g. `plink
6319 * hostname sort').
374330e2 6320 */
51470298 6321static void ssh_special(void *handle, Telnet_Special code)
32874aea 6322{
51470298 6323 Ssh ssh = (Ssh) handle;
6324
6abbf9e3 6325 if (code == TS_EOF) {
51470298 6326 if (ssh->state != SSH_STATE_SESSION) {
32874aea 6327 /*
6328 * Buffer the EOF in case we are pre-SESSION, so we can
6329 * send it as soon as we reach SESSION.
6330 */
6331 if (code == TS_EOF)
51470298 6332 ssh->eof_needed = TRUE;
32874aea 6333 return;
6334 }
51470298 6335 if (ssh->version == 1) {
6336 send_packet(ssh, SSH1_CMSG_EOF, PKT_END);
32874aea 6337 } else {
51470298 6338 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_EOF);
6339 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
6340 ssh2_pkt_send(ssh);
32874aea 6341 }
6342 logevent("Sent EOF message");
125105d1 6343 } else if (code == TS_PING || code == TS_NOP) {
51470298 6344 if (ssh->state == SSH_STATE_CLOSED
6345 || ssh->state == SSH_STATE_PREPACKET) return;
6346 if (ssh->version == 1) {
6347 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE))
6348 send_packet(ssh, SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
32874aea 6349 } else {
51470298 6350 ssh2_pkt_init(ssh, SSH2_MSG_IGNORE);
6351 ssh2_pkt_addstring_start(ssh);
6352 ssh2_pkt_send(ssh);
32874aea 6353 }
125105d1 6354 } else if (code == TS_BRK) {
6355 if (ssh->state == SSH_STATE_CLOSED
6356 || ssh->state == SSH_STATE_PREPACKET) return;
6357 if (ssh->version == 1) {
6358 logevent("Unable to send BREAK signal in SSH1");
6359 } else {
6360 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
6361 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
6362 ssh2_pkt_addstring(ssh, "break");
6363 ssh2_pkt_addbool(ssh, 0);
6364 ssh2_pkt_adduint32(ssh, 0); /* default break length */
6365 ssh2_pkt_send(ssh);
6366 }
6abbf9e3 6367 } else {
32874aea 6368 /* do nothing */
6abbf9e3 6369 }
374330e2 6370}
6371
51470298 6372void *new_sock_channel(void *handle, Socket s)
d74d141c 6373{
51470298 6374 Ssh ssh = (Ssh) handle;
d74d141c 6375 struct ssh_channel *c;
3d88e64d 6376 c = snew(struct ssh_channel);
51470298 6377 c->ssh = ssh;
d74d141c 6378
6379 if (c) {
bc240b21 6380 c->remoteid = -1; /* to be set when open confirmed */
51470298 6381 c->localid = alloc_channel_id(ssh);
d74d141c 6382 c->closes = 0;
bc240b21 6383 c->type = CHAN_SOCKDATA_DORMANT;/* identify channel type */
d74d141c 6384 c->u.pfd.s = s;
013dd8c0 6385 bufchain_init(&c->v.v2.outbuffer);
51470298 6386 add234(ssh->channels, c);
d74d141c 6387 }
6388 return c;
6389}
6390
5471d09a 6391/*
6392 * This is called when stdout/stderr (the entity to which
6393 * from_backend sends data) manages to clear some backlog.
6394 */
ae9ae89f 6395static void ssh_unthrottle(void *handle, int bufsize)
5471d09a 6396{
51470298 6397 Ssh ssh = (Ssh) handle;
6398 if (ssh->version == 1) {
6399 if (ssh->v1_stdout_throttling && bufsize < SSH1_BUFFER_LIMIT) {
6400 ssh->v1_stdout_throttling = 0;
6401 ssh1_throttle(ssh, -1);
5471d09a 6402 }
6403 } else {
51470298 6404 if (ssh->mainchan && ssh->mainchan->closes == 0)
6405 ssh2_set_window(ssh->mainchan, OUR_V2_WINSIZE - bufsize);
5471d09a 6406 }
6407}
6408
6b78788a 6409void ssh_send_port_open(void *channel, char *hostname, int port, char *org)
d74d141c 6410{
6411 struct ssh_channel *c = (struct ssh_channel *)channel;
6b78788a 6412 Ssh ssh = c->ssh;
d74d141c 6413
57356d63 6414 logeventf(ssh, "Opening forwarded connection to %s:%d", hostname, port);
d74d141c 6415
51470298 6416 if (ssh->version == 1) {
6417 send_packet(ssh, SSH1_MSG_PORT_OPEN,
bc240b21 6418 PKT_INT, c->localid,
6419 PKT_STR, hostname,
6420 PKT_INT, port,
6421 //PKT_STR, <org:orgport>,
6422 PKT_END);
6423 } else {
51470298 6424 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_OPEN);
6425 ssh2_pkt_addstring(ssh, "direct-tcpip");
6426 ssh2_pkt_adduint32(ssh, c->localid);
5471d09a 6427 c->v.v2.locwindow = OUR_V2_WINSIZE;
51470298 6428 ssh2_pkt_adduint32(ssh, c->v.v2.locwindow);/* our window size */
6429 ssh2_pkt_adduint32(ssh, 0x4000UL); /* our max pkt size */
6430 ssh2_pkt_addstring(ssh, hostname);
6431 ssh2_pkt_adduint32(ssh, port);
bc240b21 6432 /*
6433 * We make up values for the originator data; partly it's
6434 * too much hassle to keep track, and partly I'm not
6435 * convinced the server should be told details like that
6436 * about my local network configuration.
6437 */
51470298 6438 ssh2_pkt_addstring(ssh, "client-side-connection");
6439 ssh2_pkt_adduint32(ssh, 0);
6440 ssh2_pkt_send(ssh);
bc240b21 6441 }
d74d141c 6442}
6443
6444
51470298 6445static Socket ssh_socket(void *handle)
32874aea 6446{
51470298 6447 Ssh ssh = (Ssh) handle;
6448 return ssh->s;
32874aea 6449}
8ccc75b0 6450
51470298 6451static int ssh_sendok(void *handle)
32874aea 6452{
51470298 6453 Ssh ssh = (Ssh) handle;
6454 return ssh->send_ok;
32874aea 6455}
fb09bf1c 6456
51470298 6457static int ssh_ldisc(void *handle, int option)
32874aea 6458{
51470298 6459 Ssh ssh = (Ssh) handle;
32874aea 6460 if (option == LD_ECHO)
51470298 6461 return ssh->echoing;
32874aea 6462 if (option == LD_EDIT)
51470298 6463 return ssh->editing;
0965bee0 6464 return FALSE;
6465}
6466
b9d7bcad 6467static void ssh_provide_ldisc(void *handle, void *ldisc)
6468{
6469 Ssh ssh = (Ssh) handle;
6470 ssh->ldisc = ldisc;
6471}
6472
a8327734 6473static void ssh_provide_logctx(void *handle, void *logctx)
6474{
6475 Ssh ssh = (Ssh) handle;
6476 ssh->logctx = logctx;
6477}
6478
51470298 6479static int ssh_return_exitcode(void *handle)
6480{
6481 Ssh ssh = (Ssh) handle;
3bb2f322 6482 if (ssh->s != NULL)
6483 return -1;
6484 else
6485 return (ssh->exitcode >= 0 ? ssh->exitcode : 0);
51470298 6486}
6487
6488/*
6489 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
6490 * that fails. This variable is the means by which scp.c can reach
6491 * into the SSH code and find out which one it got.
6492 */
6493extern int ssh_fallback_cmd(void *handle)
d8d6c7e5 6494{
51470298 6495 Ssh ssh = (Ssh) handle;
6496 return ssh->fallback_cmd;
d8d6c7e5 6497}
6498
374330e2 6499Backend ssh_backend = {
6500 ssh_init,
fabd1805 6501 ssh_free,
86916870 6502 ssh_reconfig,
374330e2 6503 ssh_send,
5471d09a 6504 ssh_sendbuffer,
374330e2 6505 ssh_size,
4017be6d 6506 ssh_special,
125105d1 6507 ssh_get_specials,
8ccc75b0 6508 ssh_socket,
d8d6c7e5 6509 ssh_return_exitcode,
97db3be4 6510 ssh_sendok,
0965bee0 6511 ssh_ldisc,
b9d7bcad 6512 ssh_provide_ldisc,
a8327734 6513 ssh_provide_logctx,
5471d09a 6514 ssh_unthrottle,
97db3be4 6515 22
bc240b21 6516};
Local modifications for Simon Tatham's `PuTTY' SSH client and terminal emulator