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Missing bits for colour selection support.
[u/mdw/putty] / ssh.c
CommitLineData
374330e2 1#include <stdio.h>
2#include <stdlib.h>
fb09bf1c 3#include <stdarg.h>
4#include <assert.h>
374330e2 5
6#include "putty.h"
dacbd0e8 7#include "tree234.h"
fb09bf1c 8#include "ssh.h"
374330e2 9
10#ifndef FALSE
11#define FALSE 0
12#endif
13#ifndef TRUE
14#define TRUE 1
15#endif
16
32874aea 17#define SSH1_MSG_DISCONNECT 1 /* 0x1 */
18#define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
19#define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
20#define SSH1_CMSG_USER 4 /* 0x4 */
21#define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
22#define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
23#define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
24#define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
25#define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
26#define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
27#define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
28#define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
29#define SSH1_SMSG_SUCCESS 14 /* 0xe */
30#define SSH1_SMSG_FAILURE 15 /* 0xf */
31#define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
32#define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
33#define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
34#define SSH1_CMSG_EOF 19 /* 0x13 */
35#define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
36#define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
37#define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
38#define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
39#define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
40#define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
41#define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
42#define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
43#define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
44#define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
45#define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
46#define SSH1_MSG_IGNORE 32 /* 0x20 */
47#define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
48#define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
49#define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
50#define SSH1_MSG_DEBUG 36 /* 0x24 */
51#define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
52#define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
53#define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
54#define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
55#define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
56#define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
57#define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
58
59#define SSH1_AUTH_TIS 5 /* 0x5 */
60#define SSH1_AUTH_CCARD 16 /* 0x10 */
61
62#define SSH1_PROTOFLAG_SCREEN_NUMBER 1 /* 0x1 */
b96dc54c 63/* Mask for protoflags we will echo back to server if seen */
32874aea 64#define SSH1_PROTOFLAGS_SUPPORTED 0 /* 0x1 */
65
66#define SSH2_MSG_DISCONNECT 1 /* 0x1 */
67#define SSH2_MSG_IGNORE 2 /* 0x2 */
68#define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
69#define SSH2_MSG_DEBUG 4 /* 0x4 */
70#define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
71#define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
72#define SSH2_MSG_KEXINIT 20 /* 0x14 */
73#define SSH2_MSG_NEWKEYS 21 /* 0x15 */
74#define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
75#define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
76#define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */
77#define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
78#define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
79#define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
80#define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
81#define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
82#define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
83#define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
84#define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
85#define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
761187b6 86#define SSH2_MSG_USERAUTH_INFO_REQUEST 60 /* 0x3c */
87#define SSH2_MSG_USERAUTH_INFO_RESPONSE 61 /* 0x3d */
32874aea 88#define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
89#define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
90#define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
91#define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
92#define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
93#define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
94#define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
95#define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
96#define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
97#define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
98#define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
99#define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
100#define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
101#define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
102
00db133f 103/*
104 * Packet type contexts, so that ssh2_pkt_type can correctly decode
105 * the ambiguous type numbers back into the correct type strings.
106 */
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);
57476f6b 518
51470298 519struct rdpkt1_state_tag {
57476f6b 520 long len, pad, biglen, to_read;
521 unsigned long realcrc, gotcrc;
522 unsigned char *p;
523 int i;
524 int chunk;
51470298 525};
57476f6b 526
51470298 527struct rdpkt2_state_tag {
960e736a 528 long len, pad, payload, packetlen, maclen;
529 int i;
530 int cipherblk;
531 unsigned long incoming_sequence;
51470298 532};
533
534struct ssh_tag {
535 const struct plug_function_table *fn;
536 /* the above field _must_ be first in the structure */
537
538 SHA_State exhash, exhashbase;
539
540 Socket s;
541
b9d7bcad 542 void *ldisc;
a8327734 543 void *logctx;
b9d7bcad 544
51470298 545 unsigned char session_key[32];
546 int v1_compressing;
547 int v1_remote_protoflags;
548 int v1_local_protoflags;
549 int agentfwd_enabled;
550 int X11_fwd_enabled;
551 int remote_bugs;
552 const struct ssh_cipher *cipher;
371e569c 553 void *v1_cipher_ctx;
0183b242 554 void *crcda_ctx;
51470298 555 const struct ssh2_cipher *cscipher, *sccipher;
371e569c 556 void *cs_cipher_ctx, *sc_cipher_ctx;
51470298 557 const struct ssh_mac *csmac, *scmac;
e0e1a00d 558 void *cs_mac_ctx, *sc_mac_ctx;
51470298 559 const struct ssh_compress *cscomp, *sccomp;
5366aed8 560 void *cs_comp_ctx, *sc_comp_ctx;
51470298 561 const struct ssh_kex *kex;
562 const struct ssh_signkey *hostkey;
563 unsigned char v2_session_id[20];
27cd7fc2 564 void *kex_ctx;
51470298 565
566 char *savedhost;
567 int savedport;
568 int send_ok;
569 int echoing, editing;
570
571 void *frontend;
572
573 int term_width, term_height;
574
575 tree234 *channels; /* indexed by local id */
576 struct ssh_channel *mainchan; /* primary session channel */
577 int exitcode;
578
579 tree234 *rportfwds;
580
581 enum {
582 SSH_STATE_PREPACKET,
583 SSH_STATE_BEFORE_SIZE,
584 SSH_STATE_INTERMED,
585 SSH_STATE_SESSION,
586 SSH_STATE_CLOSED
587 } state;
588
589 int size_needed, eof_needed;
590
591 struct Packet pktin;
592 struct Packet pktout;
593 unsigned char *deferred_send_data;
594 int deferred_len, deferred_size;
595
596 /*
597 * Gross hack: pscp will try to start SFTP but fall back to
598 * scp1 if that fails. This variable is the means by which
599 * scp.c can reach into the SSH code and find out which one it
600 * got.
601 */
602 int fallback_cmd;
603
604 /*
605 * Used for username and password input.
606 */
607 char *userpass_input_buffer;
608 int userpass_input_buflen;
609 int userpass_input_bufpos;
610 int userpass_input_echo;
611
612 char *portfwd_strptr;
613 int pkt_ctx;
614
302121de 615 void *x11auth;
616
51470298 617 int version;
618 int v1_throttle_count;
619 int overall_bufsize;
620 int throttled_all;
621 int v1_stdout_throttling;
622 int v2_outgoing_sequence;
623
624 int ssh1_rdpkt_crstate;
625 int ssh2_rdpkt_crstate;
626 int do_ssh_init_crstate;
627 int ssh_gotdata_crstate;
628 int ssh1_protocol_crstate;
629 int do_ssh1_login_crstate;
630 int do_ssh2_transport_crstate;
631 int do_ssh2_authconn_crstate;
632
633 void *do_ssh_init_state;
634 void *do_ssh1_login_state;
635 void *do_ssh2_transport_state;
636 void *do_ssh2_authconn_state;
637
638 struct rdpkt1_state_tag rdpkt1_state;
639 struct rdpkt2_state_tag rdpkt2_state;
640
641 void (*protocol) (Ssh ssh, unsigned char *in, int inlen, int ispkt);
642 int (*s_rdpkt) (Ssh ssh, unsigned char **data, int *datalen);
86916870 643
644 /*
645 * We maintain a full _copy_ of a Config structure here, not
646 * merely a pointer to it. That way, when we're passed a new
647 * one for reconfiguration, we can check the differences and
648 * potentially reconfigure port forwardings etc in mid-session.
649 */
650 Config cfg;
51470298 651};
960e736a 652
382908ad 653#define logevent(s) logevent(ssh->frontend, s)
a8327734 654
655/* logevent, only printf-formatted. */
ae9ae89f 656static void logeventf(Ssh ssh, char *fmt, ...)
a8327734 657{
658 va_list ap;
57356d63 659 char *buf;
a8327734 660
661 va_start(ap, fmt);
57356d63 662 buf = dupvprintf(fmt, ap);
a8327734 663 va_end(ap);
57356d63 664 logevent(buf);
57356d63 665 sfree(buf);
a8327734 666}
667
6b5cf8b4 668#define bombout(msg) \
669 do { \
670 char *text = dupprintf msg; \
671 ssh->state = SSH_STATE_CLOSED; \
672 if (ssh->s) { sk_close(ssh->s); ssh->s = NULL; } \
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!"));
9a3a93a5 845 crReturn(0);
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"));
32874aea 855 crReturn(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"));
32874aea 896 crReturn(0);
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));
e14d0f19 929 crReturn(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"));
717dc483 984 crReturn(0);
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"));
32874aea 1033 crReturn(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);
3d63ca2e 1097 crReturn(0);
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"));
38d228a2 1941 crReturn(0);
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"));
38d228a2 1945 crReturn(0);
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
32874aea 2040static int ssh_closing(Plug plug, char *error_msg, int error_code,
2041 int calling_back)
2042{
51470298 2043 Ssh ssh = (Ssh) plug;
2044 ssh->state = SSH_STATE_CLOSED;
2045 if (ssh->s) {
2046 sk_close(ssh->s);
2047 ssh->s = NULL;
f3ab576e 2048 }
7e78000d 2049 if (error_msg) {
32874aea 2050 /* A socket error has occurred. */
247308b5 2051 logevent(error_msg);
a8327734 2052 connection_fatal(ssh->frontend, error_msg);
7e78000d 2053 } else {
2054 /* Otherwise, the remote side closed the connection normally. */
8df7a775 2055 }
7e78000d 2056 return 0;
2057}
2058
32874aea 2059static int ssh_receive(Plug plug, int urgent, char *data, int len)
2060{
51470298 2061 Ssh ssh = (Ssh) plug;
d8baa528 2062 ssh_gotdata(ssh, (unsigned char *)data, len);
51470298 2063 if (ssh->state == SSH_STATE_CLOSED) {
2064 if (ssh->s) {
2065 sk_close(ssh->s);
2066 ssh->s = NULL;
32874aea 2067 }
2068 return 0;
3257deae 2069 }
fef97f43 2070 return 1;
374330e2 2071}
2072
5471d09a 2073static void ssh_sent(Plug plug, int bufsize)
2074{
51470298 2075 Ssh ssh = (Ssh) plug;
5471d09a 2076 /*
2077 * If the send backlog on the SSH socket itself clears, we
2078 * should unthrottle the whole world if it was throttled.
2079 */
2080 if (bufsize < SSH_MAX_BACKLOG)
51470298 2081 ssh_throttle_all(ssh, 0, bufsize);
5471d09a 2082}
2083
fb09bf1c 2084/*
8df7a775 2085 * Connect to specified host and port.
2086 * Returns an error message, or NULL on success.
6e1ebb76 2087 * Also places the canonical host name into `realhost'. It must be
2088 * freed by the caller.
8df7a775 2089 */
51470298 2090static char *connect_to_host(Ssh ssh, char *host, int port,
2091 char **realhost, int nodelay)
8df7a775 2092{
51470298 2093 static const struct plug_function_table fn_table = {
7e78000d 2094 ssh_closing,
5471d09a 2095 ssh_receive,
2096 ssh_sent,
2097 NULL
51470298 2098 };
7e78000d 2099
8df7a775 2100 SockAddr addr;
2101 char *err;
8df7a775 2102
3d88e64d 2103 ssh->savedhost = snewn(1 + strlen(host), char);
51470298 2104 if (!ssh->savedhost)
8df7a775 2105 fatalbox("Out of memory");
51470298 2106 strcpy(ssh->savedhost, host);
8df7a775 2107
2108 if (port < 0)
2109 port = 22; /* default ssh port */
51470298 2110 ssh->savedport = port;
8df7a775 2111
2112 /*
2113 * Try to find host.
2114 */
57356d63 2115 logeventf(ssh, "Looking up host \"%s\"", host);
e8fa8f62 2116 addr = name_lookup(host, port, realhost, &ssh->cfg);
70e5d0fd 2117 if ((err = sk_addr_error(addr)) != NULL)
8df7a775 2118 return err;
2119
8df7a775 2120 /*
2121 * Open socket.
2122 */
3ad9d396 2123 {
57356d63 2124 char addrbuf[100];
3ad9d396 2125 sk_getaddr(addr, addrbuf, 100);
57356d63 2126 logeventf(ssh, "Connecting to %s port %d", addrbuf, port);
3ad9d396 2127 }
51470298 2128 ssh->fn = &fn_table;
e8fa8f62 2129 ssh->s = new_connection(addr, *realhost, port,
2130 0, 1, nodelay, (Plug) ssh, &ssh->cfg);
70e5d0fd 2131 if ((err = sk_socket_error(ssh->s)) != NULL) {
51470298 2132 ssh->s = NULL;
8df7a775 2133 return err;
67c4ba2e 2134 }
8df7a775 2135
8df7a775 2136 return NULL;
2137}
2138
2139/*
5471d09a 2140 * Throttle or unthrottle the SSH connection.
2141 */
51470298 2142static void ssh1_throttle(Ssh ssh, int adjust)
5471d09a 2143{
51470298 2144 int old_count = ssh->v1_throttle_count;
2145 ssh->v1_throttle_count += adjust;
2146 assert(ssh->v1_throttle_count >= 0);
2147 if (ssh->v1_throttle_count && !old_count) {
2148 sk_set_frozen(ssh->s, 1);
2149 } else if (!ssh->v1_throttle_count && old_count) {
2150 sk_set_frozen(ssh->s, 0);
5471d09a 2151 }
2152}
2153
2154/*
2155 * Throttle or unthrottle _all_ local data streams (for when sends
2156 * on the SSH connection itself back up).
2157 */
51470298 2158static void ssh_throttle_all(Ssh ssh, int enable, int bufsize)
5471d09a 2159{
2160 int i;
2161 struct ssh_channel *c;
2162
51470298 2163 if (enable == ssh->throttled_all)
5471d09a 2164 return;
51470298 2165 ssh->throttled_all = enable;
2166 ssh->overall_bufsize = bufsize;
2167 if (!ssh->channels)
5471d09a 2168 return;
51470298 2169 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
5471d09a 2170 switch (c->type) {
2171 case CHAN_MAINSESSION:
2172 /*
2173 * This is treated separately, outside the switch.
2174 */
2175 break;
2176 case CHAN_X11:
2177 x11_override_throttle(c->u.x11.s, enable);
2178 break;
2179 case CHAN_AGENT:
2180 /* Agent channels require no buffer management. */
2181 break;
2182 case CHAN_SOCKDATA:
2183 pfd_override_throttle(c->u.x11.s, enable);
2184 break;
2185 }
2186 }
2187}
2188
2189/*
51470298 2190 * Username and password input, abstracted off into routines
2191 * reusable in several places - even between SSH1 and SSH2.
0405e71f 2192 */
0405e71f 2193
2194/* Set up a username or password input loop on a given buffer. */
ae9ae89f 2195static void setup_userpass_input(Ssh ssh, char *buffer, int buflen, int echo)
0405e71f 2196{
51470298 2197 ssh->userpass_input_buffer = buffer;
2198 ssh->userpass_input_buflen = buflen;
2199 ssh->userpass_input_bufpos = 0;
2200 ssh->userpass_input_echo = echo;
0405e71f 2201}
2202
2203/*
2204 * Process some terminal data in the course of username/password
2205 * input. Returns >0 for success (line of input returned in
2206 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2207 * for inconclusive (keep waiting for more input please).
2208 */
ae9ae89f 2209static int process_userpass_input(Ssh ssh, unsigned char *in, int inlen)
0405e71f 2210{
2211 char c;
2212
2213 while (inlen--) {
2214 switch (c = *in++) {
2215 case 10:
2216 case 13:
51470298 2217 ssh->userpass_input_buffer[ssh->userpass_input_bufpos] = 0;
2218 ssh->userpass_input_buffer[ssh->userpass_input_buflen-1] = 0;
0405e71f 2219 return +1;
2220 break;
2221 case 8:
2222 case 127:
51470298 2223 if (ssh->userpass_input_bufpos > 0) {
2224 if (ssh->userpass_input_echo)
2225 c_write_str(ssh, "\b \b");
2226 ssh->userpass_input_bufpos--;
0405e71f 2227 }
2228 break;
2229 case 21:
2230 case 27:
51470298 2231 while (ssh->userpass_input_bufpos > 0) {
2232 if (ssh->userpass_input_echo)
2233 c_write_str(ssh, "\b \b");
2234 ssh->userpass_input_bufpos--;
0405e71f 2235 }
2236 break;
2237 case 3:
2238 case 4:
2239 return -1;
2240 break;
2241 default:
4692a14a 2242 /*
2243 * This simplistic check for printability is disabled
2244 * when we're doing password input, because some people
2245 * have control characters in their passwords.o
2246 */
2247 if ((!ssh->userpass_input_echo ||
2248 (c >= ' ' && c <= '~') ||
0405e71f 2249 ((unsigned char) c >= 160))
51470298 2250 && ssh->userpass_input_bufpos < ssh->userpass_input_buflen-1) {
2251 ssh->userpass_input_buffer[ssh->userpass_input_bufpos++] = c;
2252 if (ssh->userpass_input_echo)
2253 c_write(ssh, &c, 1);
0405e71f 2254 }
2255 break;
2256 }
2257 }
2258 return 0;
2259}
2260
2261/*
fb09bf1c 2262 * Handle the key exchange and user authentication phases.
2263 */
51470298 2264static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
fb09bf1c 2265{
2d466ffd 2266 int i, j;
374330e2 2267 unsigned char cookie[8];
2268 struct RSAKey servkey, hostkey;
2269 struct MD5Context md5c;
51470298 2270 struct do_ssh1_login_state {
2271 int len;
2272 unsigned char *rsabuf, *keystr1, *keystr2;
2273 unsigned long supported_ciphers_mask, supported_auths_mask;
2274 int tried_publickey, tried_agent;
2275 int tis_auth_refused, ccard_auth_refused;
2276 unsigned char session_id[16];
2277 int cipher_type;
2278 char username[100];
2279 void *publickey_blob;
2280 int publickey_bloblen;
2281 char password[100];
2282 char prompt[200];
2283 int pos;
2284 char c;
2285 int pwpkt_type;
2286 unsigned char request[5], *response, *p;
2287 int responselen;
2288 int keyi, nkeys;
2289 int authed;
2290 struct RSAKey key;
2291 Bignum challenge;
2292 char *commentp;
2293 int commentlen;
2294 };
2295 crState(do_ssh1_login_state);
2296
2297 crBegin(ssh->do_ssh1_login_crstate);
374330e2 2298
32874aea 2299 if (!ispkt)
2300 crWaitUntil(ispkt);
374330e2 2301
51470298 2302 if (ssh->pktin.type != SSH1_SMSG_PUBLIC_KEY) {
6b5cf8b4 2303 bombout(("Public key packet not received"));
32874aea 2304 crReturn(0);
8d5de777 2305 }
374330e2 2306
c5e9c988 2307 logevent("Received public keys");
374330e2 2308
51470298 2309 memcpy(cookie, ssh->pktin.body, 8);
374330e2 2310
51470298 2311 i = makekey(ssh->pktin.body + 8, &servkey, &s->keystr1, 0);
2312 j = makekey(ssh->pktin.body + 8 + i, &hostkey, &s->keystr2, 0);
374330e2 2313
c5e9c988 2314 /*
1c2a93c4 2315 * Log the host key fingerprint.
c5e9c988 2316 */
c5e9c988 2317 {
2318 char logmsg[80];
1c2a93c4 2319 logevent("Host key fingerprint is:");
c5e9c988 2320 strcpy(logmsg, " ");
32874aea 2321 hostkey.comment = NULL;
2322 rsa_fingerprint(logmsg + strlen(logmsg),
2323 sizeof(logmsg) - strlen(logmsg), &hostkey);
c5e9c988 2324 logevent(logmsg);
2325 }
2326
51470298 2327 ssh->v1_remote_protoflags = GET_32BIT(ssh->pktin.body + 8 + i + j);
2328 s->supported_ciphers_mask = GET_32BIT(ssh->pktin.body + 12 + i + j);
2329 s->supported_auths_mask = GET_32BIT(ssh->pktin.body + 16 + i + j);
bea1ef5f 2330
51470298 2331 ssh->v1_local_protoflags =
2332 ssh->v1_remote_protoflags & SSH1_PROTOFLAGS_SUPPORTED;
2333 ssh->v1_local_protoflags |= SSH1_PROTOFLAG_SCREEN_NUMBER;
b96dc54c 2334
c5e9c988 2335 MD5Init(&md5c);
51470298 2336 MD5Update(&md5c, s->keystr2, hostkey.bytes);
2337 MD5Update(&md5c, s->keystr1, servkey.bytes);
2338 MD5Update(&md5c, ssh->pktin.body, 8);
2339 MD5Final(s->session_id, &md5c);
374330e2 2340
32874aea 2341 for (i = 0; i < 32; i++)
51470298 2342 ssh->session_key[i] = random_byte();
374330e2 2343
51470298 2344 s->len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
374330e2 2345
3d88e64d 2346 s->rsabuf = snewn(s->len, unsigned char);
51470298 2347 if (!s->rsabuf)
374330e2 2348 fatalbox("Out of memory");
2349
89ee5268 2350 /*
2351 * Verify the host key.
2352 */
2353 {
32874aea 2354 /*
2355 * First format the key into a string.
2356 */
2357 int len = rsastr_len(&hostkey);
2358 char fingerprint[100];
3d88e64d 2359 char *keystr = snewn(len, char);
32874aea 2360 if (!keystr)
2361 fatalbox("Out of memory");
2362 rsastr_fmt(keystr, &hostkey);
2363 rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
a8327734 2364 verify_ssh_host_key(ssh->frontend,
2365 ssh->savedhost, ssh->savedport, "rsa", keystr,
32874aea 2366 fingerprint);
2367 sfree(keystr);
2368 }
2369
2370 for (i = 0; i < 32; i++) {
51470298 2371 s->rsabuf[i] = ssh->session_key[i];
374330e2 2372 if (i < 16)
51470298 2373 s->rsabuf[i] ^= s->session_id[i];
374330e2 2374 }
2375
2376 if (hostkey.bytes > servkey.bytes) {
51470298 2377 rsaencrypt(s->rsabuf, 32, &servkey);
2378 rsaencrypt(s->rsabuf, servkey.bytes, &hostkey);
374330e2 2379 } else {
51470298 2380 rsaencrypt(s->rsabuf, 32, &hostkey);
2381 rsaencrypt(s->rsabuf, hostkey.bytes, &servkey);
374330e2 2382 }
2383
c5e9c988 2384 logevent("Encrypted session key");
2385
ca20bfcf 2386 {
2387 int cipher_chosen = 0, warn = 0;
2388 char *cipher_string = NULL;
51470298 2389 int i;
ca20bfcf 2390 for (i = 0; !cipher_chosen && i < CIPHER_MAX; i++) {
86916870 2391 int next_cipher = ssh->cfg.ssh_cipherlist[i];
ca20bfcf 2392 if (next_cipher == CIPHER_WARN) {
2393 /* If/when we choose a cipher, warn about it */
2394 warn = 1;
2395 } else if (next_cipher == CIPHER_AES) {
2396 /* XXX Probably don't need to mention this. */
2397 logevent("AES not supported in SSH1, skipping");
2398 } else {
2399 switch (next_cipher) {
51470298 2400 case CIPHER_3DES: s->cipher_type = SSH_CIPHER_3DES;
ca20bfcf 2401 cipher_string = "3DES"; break;
51470298 2402 case CIPHER_BLOWFISH: s->cipher_type = SSH_CIPHER_BLOWFISH;
ca20bfcf 2403 cipher_string = "Blowfish"; break;
51470298 2404 case CIPHER_DES: s->cipher_type = SSH_CIPHER_DES;
ca20bfcf 2405 cipher_string = "single-DES"; break;
2406 }
51470298 2407 if (s->supported_ciphers_mask & (1 << s->cipher_type))
ca20bfcf 2408 cipher_chosen = 1;
2409 }
2410 }
2411 if (!cipher_chosen) {
51470298 2412 if ((s->supported_ciphers_mask & (1 << SSH_CIPHER_3DES)) == 0)
6b5cf8b4 2413 bombout(("Server violates SSH 1 protocol by not "
ca20bfcf 2414 "supporting 3DES encryption"));
2415 else
2416 /* shouldn't happen */
6b5cf8b4 2417 bombout(("No supported ciphers found"));
a99a05c0 2418 crReturn(0);
2419 }
ca20bfcf 2420
2421 /* Warn about chosen cipher if necessary. */
2422 if (warn)
a8327734 2423 askcipher(ssh->frontend, cipher_string, 0);
bea1ef5f 2424 }
ca20bfcf 2425
51470298 2426 switch (s->cipher_type) {
32874aea 2427 case SSH_CIPHER_3DES:
2428 logevent("Using 3DES encryption");
2429 break;
2430 case SSH_CIPHER_DES:
2431 logevent("Using single-DES encryption");
2432 break;
2433 case SSH_CIPHER_BLOWFISH:
2434 logevent("Using Blowfish encryption");
2435 break;
c5e9c988 2436 }
bea1ef5f 2437
51470298 2438 send_packet(ssh, SSH1_CMSG_SESSION_KEY,
2439 PKT_CHAR, s->cipher_type,
32874aea 2440 PKT_DATA, cookie, 8,
51470298 2441 PKT_CHAR, (s->len * 8) >> 8, PKT_CHAR, (s->len * 8) & 0xFF,
2442 PKT_DATA, s->rsabuf, s->len,
2443 PKT_INT, ssh->v1_local_protoflags, PKT_END);
fb09bf1c 2444
c5e9c988 2445 logevent("Trying to enable encryption...");
374330e2 2446
51470298 2447 sfree(s->rsabuf);
374330e2 2448
51470298 2449 ssh->cipher = (s->cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
2450 s->cipher_type == SSH_CIPHER_DES ? &ssh_des :
2451 &ssh_3des);
371e569c 2452 ssh->v1_cipher_ctx = ssh->cipher->make_context();
2453 ssh->cipher->sesskey(ssh->v1_cipher_ctx, ssh->session_key);
57356d63 2454 logeventf(ssh, "Initialised %s encryption", ssh->cipher->text_name);
374330e2 2455
0183b242 2456 ssh->crcda_ctx = crcda_make_context();
2457 logevent("Installing CRC compensation attack detector");
2458
fb09bf1c 2459 crWaitUntil(ispkt);
374330e2 2460
51470298 2461 if (ssh->pktin.type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 2462 bombout(("Encryption not successfully enabled"));
32874aea 2463 crReturn(0);
8d5de777 2464 }
374330e2 2465
c5e9c988 2466 logevent("Successfully started encryption");
2467
374330e2 2468 fflush(stdout);
2469 {
86916870 2470 if ((flags & FLAG_INTERACTIVE) && !*ssh->cfg.username) {
c0a81592 2471 if (ssh_get_line && !ssh_getline_pw_only) {
32874aea 2472 if (!ssh_get_line("login as: ",
51470298 2473 s->username, sizeof(s->username), FALSE)) {
32874aea 2474 /*
2475 * get_line failed to get a username.
2476 * Terminate.
2477 */
2478 logevent("No username provided. Abandoning session.");
3bb2f322 2479 ssh_closing((Plug)ssh, NULL, 0, 0);
32874aea 2480 crReturn(1);
2481 }
2482 } else {
51470298 2483 int ret; /* need not be kept over crReturn */
2484 c_write_str(ssh, "login as: ");
2485 ssh->send_ok = 1;
0405e71f 2486
51470298 2487 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
0405e71f 2488 do {
32874aea 2489 crWaitUntil(!ispkt);
51470298 2490 ret = process_userpass_input(ssh, in, inlen);
0405e71f 2491 } while (ret == 0);
2492 if (ret < 0)
2493 cleanup_exit(0);
51470298 2494 c_write_str(ssh, "\r\n");
32874aea 2495 }
2496 } else {
86916870 2497 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
51470298 2498 s->username[sizeof(s->username)-1] = '\0';
374330e2 2499 }
fb09bf1c 2500
51470298 2501 send_packet(ssh, SSH1_CMSG_USER, PKT_STR, s->username, PKT_END);
c5e9c988 2502 {
51470298 2503 char userlog[22 + sizeof(s->username)];
2504 sprintf(userlog, "Sent username \"%s\"", s->username);
c5e9c988 2505 logevent(userlog);
32874aea 2506 if (flags & FLAG_INTERACTIVE &&
2507 (!((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)))) {
3c8e959b 2508 strcat(userlog, "\r\n");
51470298 2509 c_write_str(ssh, userlog);
3c8e959b 2510 }
c5e9c988 2511 }
374330e2 2512 }
2513
fb09bf1c 2514 crWaitUntil(ispkt);
374330e2 2515
51470298 2516 if ((ssh->remote_bugs & BUG_CHOKES_ON_RSA)) {
0df73905 2517 /* We must not attempt PK auth. Pretend we've already tried it. */
51470298 2518 s->tried_publickey = s->tried_agent = 1;
0df73905 2519 } else {
51470298 2520 s->tried_publickey = s->tried_agent = 0;
0df73905 2521 }
51470298 2522 s->tis_auth_refused = s->ccard_auth_refused = 0;
86916870 2523 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
9a30e26b 2524 if (!filename_is_null(ssh->cfg.keyfile)) {
2525 if (!rsakey_pubblob(&ssh->cfg.keyfile,
51470298 2526 &s->publickey_blob, &s->publickey_bloblen))
2527 s->publickey_blob = NULL;
396778f1 2528 } else
51470298 2529 s->publickey_blob = NULL;
7cca0d81 2530
51470298 2531 while (ssh->pktin.type == SSH1_SMSG_FAILURE) {
2532 s->pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
614a20a0 2533
51470298 2534 if (agent_exists() && !s->tried_agent) {
32874aea 2535 /*
2536 * Attempt RSA authentication using Pageant.
2537 */
32874aea 2538 void *r;
2539
51470298 2540 s->authed = FALSE;
2541 s->tried_agent = 1;
32874aea 2542 logevent("Pageant is running. Requesting keys.");
2543
2544 /* Request the keys held by the agent. */
51470298 2545 PUT_32BIT(s->request, 1);
2546 s->request[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES;
2547 agent_query(s->request, 5, &r, &s->responselen);
2548 s->response = (unsigned char *) r;
2549 if (s->response && s->responselen >= 5 &&
2550 s->response[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER) {
2551 s->p = s->response + 5;
2552 s->nkeys = GET_32BIT(s->p);
2553 s->p += 4;
32874aea 2554 {
2555 char buf[64];
51470298 2556 sprintf(buf, "Pageant has %d SSH1 keys", s->nkeys);
32874aea 2557 logevent(buf);
2558 }
51470298 2559 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
32874aea 2560 {
2561 char buf[64];
51470298 2562 sprintf(buf, "Trying Pageant key #%d", s->keyi);
32874aea 2563 logevent(buf);
2564 }
51470298 2565 if (s->publickey_blob &&
2566 !memcmp(s->p, s->publickey_blob,
2567 s->publickey_bloblen)) {
396778f1 2568 logevent("This key matches configured key file");
51470298 2569 s->tried_publickey = 1;
396778f1 2570 }
51470298 2571 s->p += 4;
2572 s->p += ssh1_read_bignum(s->p, &s->key.exponent);
2573 s->p += ssh1_read_bignum(s->p, &s->key.modulus);
2574 s->commentlen = GET_32BIT(s->p);
2575 s->p += 4;
d8baa528 2576 s->commentp = (char *)s->p;
51470298 2577 s->p += s->commentlen;
2578 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
2579 PKT_BIGNUM, s->key.modulus, PKT_END);
32874aea 2580 crWaitUntil(ispkt);
51470298 2581 if (ssh->pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
32874aea 2582 logevent("Key refused");
2583 continue;
2584 }
2585 logevent("Received RSA challenge");
51470298 2586 ssh1_read_bignum(ssh->pktin.body, &s->challenge);
32874aea 2587 {
2588 char *agentreq, *q, *ret;
2d466ffd 2589 void *vret;
32874aea 2590 int len, retlen;
2591 len = 1 + 4; /* message type, bit count */
51470298 2592 len += ssh1_bignum_length(s->key.exponent);
2593 len += ssh1_bignum_length(s->key.modulus);
2594 len += ssh1_bignum_length(s->challenge);
32874aea 2595 len += 16; /* session id */
2596 len += 4; /* response format */
3d88e64d 2597 agentreq = snewn(4 + len, char);
32874aea 2598 PUT_32BIT(agentreq, len);
2599 q = agentreq + 4;
2600 *q++ = SSH1_AGENTC_RSA_CHALLENGE;
51470298 2601 PUT_32BIT(q, bignum_bitcount(s->key.modulus));
32874aea 2602 q += 4;
51470298 2603 q += ssh1_write_bignum(q, s->key.exponent);
2604 q += ssh1_write_bignum(q, s->key.modulus);
2605 q += ssh1_write_bignum(q, s->challenge);
2606 memcpy(q, s->session_id, 16);
32874aea 2607 q += 16;
2608 PUT_32BIT(q, 1); /* response format */
2d466ffd 2609 agent_query(agentreq, len + 4, &vret, &retlen);
2610 ret = vret;
32874aea 2611 sfree(agentreq);
2612 if (ret) {
2613 if (ret[4] == SSH1_AGENT_RSA_RESPONSE) {
2614 logevent("Sending Pageant's response");
51470298 2615 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
32874aea 2616 PKT_DATA, ret + 5, 16,
2617 PKT_END);
2618 sfree(ret);
2619 crWaitUntil(ispkt);
51470298 2620 if (ssh->pktin.type == SSH1_SMSG_SUCCESS) {
32874aea 2621 logevent
2622 ("Pageant's response accepted");
2623 if (flags & FLAG_VERBOSE) {
51470298 2624 c_write_str(ssh, "Authenticated using"
2625 " RSA key \"");
2626 c_write(ssh, s->commentp,
2627 s->commentlen);
2628 c_write_str(ssh, "\" from agent\r\n");
32874aea 2629 }
51470298 2630 s->authed = TRUE;
32874aea 2631 } else
2632 logevent
2633 ("Pageant's response not accepted");
2634 } else {
2635 logevent
2636 ("Pageant failed to answer challenge");
2637 sfree(ret);
2638 }
2639 } else {
2640 logevent("No reply received from Pageant");
2641 }
2642 }
51470298 2643 freebn(s->key.exponent);
2644 freebn(s->key.modulus);
2645 freebn(s->challenge);
2646 if (s->authed)
32874aea 2647 break;
2648 }
2649 }
51470298 2650 if (s->authed)
32874aea 2651 break;
2652 }
9a30e26b 2653 if (!filename_is_null(ssh->cfg.keyfile) && !s->tried_publickey)
51470298 2654 s->pwpkt_type = SSH1_CMSG_AUTH_RSA;
32874aea 2655
86916870 2656 if (ssh->cfg.try_tis_auth &&
51470298 2657 (s->supported_auths_mask & (1 << SSH1_AUTH_TIS)) &&
2658 !s->tis_auth_refused) {
2659 s->pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
32874aea 2660 logevent("Requested TIS authentication");
51470298 2661 send_packet(ssh, SSH1_CMSG_AUTH_TIS, PKT_END);
32874aea 2662 crWaitUntil(ispkt);
51470298 2663 if (ssh->pktin.type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
32874aea 2664 logevent("TIS authentication declined");
2665 if (flags & FLAG_INTERACTIVE)
51470298 2666 c_write_str(ssh, "TIS authentication refused.\r\n");
2667 s->tis_auth_refused = 1;
614a20a0 2668 continue;
32874aea 2669 } else {
51470298 2670 int challengelen = GET_32BIT(ssh->pktin.body);
32874aea 2671 logevent("Received TIS challenge");
51470298 2672 if (challengelen > sizeof(s->prompt) - 1)
2673 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
2674 memcpy(s->prompt, ssh->pktin.body + 4, challengelen);
614a20a0 2675 /* Prompt heuristic comes from OpenSSH */
51470298 2676 strncpy(s->prompt + challengelen,
2677 memchr(s->prompt, '\n', challengelen) ?
614a20a0 2678 "": "\r\nResponse: ",
51470298 2679 (sizeof s->prompt) - challengelen);
2680 s->prompt[(sizeof s->prompt) - 1] = '\0';
32874aea 2681 }
2682 }
86916870 2683 if (ssh->cfg.try_tis_auth &&
51470298 2684 (s->supported_auths_mask & (1 << SSH1_AUTH_CCARD)) &&
2685 !s->ccard_auth_refused) {
2686 s->pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
32874aea 2687 logevent("Requested CryptoCard authentication");
51470298 2688 send_packet(ssh, SSH1_CMSG_AUTH_CCARD, PKT_END);
32874aea 2689 crWaitUntil(ispkt);
51470298 2690 if (ssh->pktin.type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
32874aea 2691 logevent("CryptoCard authentication declined");
51470298 2692 c_write_str(ssh, "CryptoCard authentication refused.\r\n");
2693 s->ccard_auth_refused = 1;
614a20a0 2694 continue;
32874aea 2695 } else {
51470298 2696 int challengelen = GET_32BIT(ssh->pktin.body);
32874aea 2697 logevent("Received CryptoCard challenge");
51470298 2698 if (challengelen > sizeof(s->prompt) - 1)
2699 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
2700 memcpy(s->prompt, ssh->pktin.body + 4, challengelen);
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 }
51470298 2708 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
2709 sprintf(s->prompt, "%.90s@%.90s's password: ",
2710 s->username, ssh->savedhost);
32874aea 2711 }
51470298 2712 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
32874aea 2713 char *comment = NULL;
231ee168 2714 int type;
2715 char msgbuf[256];
32874aea 2716 if (flags & FLAG_VERBOSE)
51470298 2717 c_write_str(ssh, "Trying public key authentication.\r\n");
6c6d9ed9 2718 logeventf(ssh, "Trying public key \"%s\"",
2719 filename_to_str(&ssh->cfg.keyfile));
9a30e26b 2720 type = key_type(&ssh->cfg.keyfile);
231ee168 2721 if (type != SSH_KEYTYPE_SSH1) {
2722 sprintf(msgbuf, "Key is of wrong type (%s)",
2723 key_type_to_str(type));
2724 logevent(msgbuf);
51470298 2725 c_write_str(ssh, msgbuf);
2726 c_write_str(ssh, "\r\n");
2727 s->tried_publickey = 1;
231ee168 2728 continue;
2729 }
9a30e26b 2730 if (!rsakey_encrypted(&ssh->cfg.keyfile, &comment)) {
32874aea 2731 if (flags & FLAG_VERBOSE)
51470298 2732 c_write_str(ssh, "No passphrase required.\r\n");
32874aea 2733 goto tryauth;
2734 }
51470298 2735 sprintf(s->prompt, "Passphrase for key \"%.100s\": ", comment);
32874aea 2736 sfree(comment);
2737 }
a52f067e 2738
614a20a0 2739 /*
2740 * Show password prompt, having first obtained it via a TIS
2741 * or CryptoCard exchange if we're doing TIS or CryptoCard
2742 * authentication.
2743 */
fa17a66e 2744 if (ssh_get_line) {
51470298 2745 if (!ssh_get_line(s->prompt, s->password,
2746 sizeof(s->password), TRUE)) {
32874aea 2747 /*
2748 * get_line failed to get a password (for example
2749 * because one was supplied on the command line
2750 * which has already failed to work). Terminate.
2751 */
51470298 2752 send_packet(ssh, SSH1_MSG_DISCONNECT,
2bc6a386 2753 PKT_STR, "No more passwords available to try",
2754 PKT_END);
247308b5 2755 logevent("Unable to authenticate");
a8327734 2756 connection_fatal(ssh->frontend, "Unable to authenticate");
3bb2f322 2757 ssh_closing((Plug)ssh, NULL, 0, 0);
32874aea 2758 crReturn(1);
2759 }
fb09bf1c 2760 } else {
614a20a0 2761 /* Prompt may have come from server. We've munged it a bit, so
2762 * we know it to be zero-terminated at least once. */
51470298 2763 int ret; /* need not be saved over crReturn */
2764 c_write_untrusted(ssh, s->prompt, strlen(s->prompt));
2765 s->pos = 0;
0405e71f 2766
51470298 2767 setup_userpass_input(ssh, s->password, sizeof(s->password), 0);
0405e71f 2768 do {
32874aea 2769 crWaitUntil(!ispkt);
51470298 2770 ret = process_userpass_input(ssh, in, inlen);
0405e71f 2771 } while (ret == 0);
2772 if (ret < 0)
2773 cleanup_exit(0);
51470298 2774 c_write_str(ssh, "\r\n");
32874aea 2775 }
2776
2777 tryauth:
51470298 2778 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
32874aea 2779 /*
2780 * Try public key authentication with the specified
2781 * key file.
2782 */
51470298 2783 s->tried_publickey = 1;
2784
2785 {
9a30e26b 2786 int ret = loadrsakey(&ssh->cfg.keyfile, &s->key, s->password);
51470298 2787 if (ret == 0) {
2788 c_write_str(ssh, "Couldn't load private key from ");
9fab77dc 2789 c_write_str(ssh, filename_to_str(&ssh->cfg.keyfile));
51470298 2790 c_write_str(ssh, ".\r\n");
2791 continue; /* go and try password */
2792 }
2793 if (ret == -1) {
2794 c_write_str(ssh, "Wrong passphrase.\r\n");
2795 s->tried_publickey = 0;
2796 continue; /* try again */
2797 }
32874aea 2798 }
2799
2800 /*
2801 * Send a public key attempt.
2802 */
51470298 2803 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
2804 PKT_BIGNUM, s->key.modulus, PKT_END);
32874aea 2805
2806 crWaitUntil(ispkt);
51470298 2807 if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
2808 c_write_str(ssh, "Server refused our public key.\r\n");
32874aea 2809 continue; /* go and try password */
2810 }
51470298 2811 if (ssh->pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
6b5cf8b4 2812 bombout(("Bizarre response to offer of public key"));
32874aea 2813 crReturn(0);
2814 }
32874aea 2815
51470298 2816 {
2817 int i;
2818 unsigned char buffer[32];
2819 Bignum challenge, response;
2820
2821 ssh1_read_bignum(ssh->pktin.body, &challenge);
2822 response = rsadecrypt(challenge, &s->key);
2823 freebn(s->key.private_exponent);/* burn the evidence */
32874aea 2824
51470298 2825 for (i = 0; i < 32; i++) {
2826 buffer[i] = bignum_byte(response, 31 - i);
2827 }
2828
2829 MD5Init(&md5c);
2830 MD5Update(&md5c, buffer, 32);
2831 MD5Update(&md5c, s->session_id, 16);
2832 MD5Final(buffer, &md5c);
32874aea 2833
51470298 2834 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
2835 PKT_DATA, buffer, 16, PKT_END);
2836
2837 freebn(challenge);
2838 freebn(response);
2839 }
32874aea 2840
2841 crWaitUntil(ispkt);
51470298 2842 if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
32874aea 2843 if (flags & FLAG_VERBOSE)
51470298 2844 c_write_str(ssh, "Failed to authenticate with"
2845 " our public key.\r\n");
32874aea 2846 continue; /* go and try password */
51470298 2847 } else if (ssh->pktin.type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 2848 bombout(("Bizarre response to RSA authentication response"));
32874aea 2849 crReturn(0);
2850 }
2851
2852 break; /* we're through! */
2853 } else {
51470298 2854 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
32874aea 2855 /*
2856 * Defence against traffic analysis: we send a
2857 * whole bunch of packets containing strings of
2858 * different lengths. One of these strings is the
2859 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
2860 * The others are all random data in
2861 * SSH1_MSG_IGNORE packets. This way a passive
2862 * listener can't tell which is the password, and
2863 * hence can't deduce the password length.
2864 *
2865 * Anybody with a password length greater than 16
2866 * bytes is going to have enough entropy in their
2867 * password that a listener won't find it _that_
2868 * much help to know how long it is. So what we'll
2869 * do is:
2870 *
2871 * - if password length < 16, we send 15 packets
2872 * containing string lengths 1 through 15
2873 *
2874 * - otherwise, we let N be the nearest multiple
2875 * of 8 below the password length, and send 8
2876 * packets containing string lengths N through
2877 * N+7. This won't obscure the order of
2878 * magnitude of the password length, but it will
2879 * introduce a bit of extra uncertainty.
2880 *
2881 * A few servers (the old 1.2.18 through 1.2.22)
2882 * can't deal with SSH1_MSG_IGNORE. For these
2883 * servers, we need an alternative defence. We make
2884 * use of the fact that the password is interpreted
2885 * as a C string: so we can append a NUL, then some
2886 * random data.
bd358db1 2887 *
2888 * One server (a Cisco one) can deal with neither
2889 * SSH1_MSG_IGNORE _nor_ a padded password string.
2890 * For this server we are left with no defences
2891 * against password length sniffing.
32874aea 2892 */
51470298 2893 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE)) {
b17c8428 2894 /*
2895 * The server can deal with SSH1_MSG_IGNORE, so
2896 * we can use the primary defence.
2897 */
32874aea 2898 int bottom, top, pwlen, i;
2899 char *randomstr;
2900
51470298 2901 pwlen = strlen(s->password);
32874aea 2902 if (pwlen < 16) {
2903 bottom = 0; /* zero length passwords are OK! :-) */
2904 top = 15;
2905 } else {
2906 bottom = pwlen & ~7;
2907 top = bottom + 7;
2908 }
2909
2910 assert(pwlen >= bottom && pwlen <= top);
2911
3d88e64d 2912 randomstr = snewn(top + 1, char);
32874aea 2913
2914 for (i = bottom; i <= top; i++) {
2915 if (i == pwlen)
51470298 2916 defer_packet(ssh, s->pwpkt_type,
2917 PKT_STR, s->password, PKT_END);
32874aea 2918 else {
2919 for (j = 0; j < i; j++) {
2920 do {
2921 randomstr[j] = random_byte();
2922 } while (randomstr[j] == '\0');
2923 }
2924 randomstr[i] = '\0';
51470298 2925 defer_packet(ssh, SSH1_MSG_IGNORE,
32874aea 2926 PKT_STR, randomstr, PKT_END);
2927 }
2928 }
bd358db1 2929 logevent("Sending password with camouflage packets");
51470298 2930 ssh_pkt_defersend(ssh);
bd358db1 2931 }
51470298 2932 else if (!(ssh->remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
b17c8428 2933 /*
2934 * The server can't deal with SSH1_MSG_IGNORE
2935 * but can deal with padded passwords, so we
2936 * can use the secondary defence.
2937 */
bd358db1 2938 char string[64];
51470298 2939 char *ss;
bd358db1 2940 int len;
2941
51470298 2942 len = strlen(s->password);
bd358db1 2943 if (len < sizeof(string)) {
51470298 2944 ss = string;
2945 strcpy(string, s->password);
bd358db1 2946 len++; /* cover the zero byte */
2947 while (len < sizeof(string)) {
2948 string[len++] = (char) random_byte();
2949 }
2950 } else {
51470298 2951 ss = s->password;
bd358db1 2952 }
2953 logevent("Sending length-padded password");
51470298 2954 send_packet(ssh, s->pwpkt_type, PKT_INT, len,
2955 PKT_DATA, ss, len, PKT_END);
bd358db1 2956 } else {
2957 /*
2958 * The server has _both_
2959 * BUG_CHOKES_ON_SSH1_IGNORE and
2960 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
2961 * therefore nothing we can do.
2962 */
2963 int len;
51470298 2964 len = strlen(s->password);
bd358db1 2965 logevent("Sending unpadded password");
51470298 2966 send_packet(ssh, s->pwpkt_type, PKT_INT, len,
2967 PKT_DATA, s->password, len, PKT_END);
32874aea 2968 }
2969 } else {
51470298 2970 send_packet(ssh, s->pwpkt_type, PKT_STR, s->password, PKT_END);
32874aea 2971 }
2972 }
c5e9c988 2973 logevent("Sent password");
51470298 2974 memset(s->password, 0, strlen(s->password));
fb09bf1c 2975 crWaitUntil(ispkt);
51470298 2976 if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
32874aea 2977 if (flags & FLAG_VERBOSE)
51470298 2978 c_write_str(ssh, "Access denied\r\n");
c5e9c988 2979 logevent("Authentication refused");
51470298 2980 } else if (ssh->pktin.type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 2981 bombout(("Strange packet received, type %d", ssh->pktin.type));
32874aea 2982 crReturn(0);
374330e2 2983 }
2984 }
2985
c5e9c988 2986 logevent("Authentication successful");
2987
fb09bf1c 2988 crFinish(1);
2989}
2990
32874aea 2991void sshfwd_close(struct ssh_channel *c)
2992{
51470298 2993 Ssh ssh = c->ssh;
2994
80e48603 2995 if (c && !c->closes) {
4ed34d25 2996 /*
2997 * If the channel's remoteid is -1, we have sent
2998 * CHANNEL_OPEN for this channel, but it hasn't even been
2999 * acknowledged by the server. So we must set a close flag
3000 * on it now, and then when the server acks the channel
3001 * open, we can close it then.
3002 */
36cac739 3003 if (((int)c->remoteid) != -1) {
51470298 3004 if (ssh->version == 1) {
3005 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid,
4ed34d25 3006 PKT_END);
3007 } else {
51470298 3008 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_CLOSE);
3009 ssh2_pkt_adduint32(ssh, c->remoteid);
3010 ssh2_pkt_send(ssh);
4ed34d25 3011 }
32874aea 3012 }
0357890f 3013 c->closes = 1; /* sent MSG_CLOSE */
32874aea 3014 if (c->type == CHAN_X11) {
3015 c->u.x11.s = NULL;
d74d141c 3016 logevent("Forwarded X11 connection terminated");
4ed34d25 3017 } else if (c->type == CHAN_SOCKDATA ||
3018 c->type == CHAN_SOCKDATA_DORMANT) {
d74d141c 3019 c->u.pfd.s = NULL;
3020 logevent("Forwarded port closed");
32874aea 3021 }
3022 }
3023}
3024
5471d09a 3025int sshfwd_write(struct ssh_channel *c, char *buf, int len)
32874aea 3026{
51470298 3027 Ssh ssh = c->ssh;
3028
3029 if (ssh->version == 1) {
3030 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
32874aea 3031 PKT_INT, c->remoteid,
3032 PKT_INT, len, PKT_DATA, buf, len, PKT_END);
5471d09a 3033 /*
3034 * In SSH1 we can return 0 here - implying that forwarded
3035 * connections are never individually throttled - because
3036 * the only circumstance that can cause throttling will be
3037 * the whole SSH connection backing up, in which case
3038 * _everything_ will be throttled as a whole.
3039 */
3040 return 0;
783415f8 3041 } else {
32874aea 3042 ssh2_add_channel_data(c, buf, len);
5471d09a 3043 return ssh2_try_send(c);
3044 }
3045}
3046
3047void sshfwd_unthrottle(struct ssh_channel *c, int bufsize)
3048{
51470298 3049 Ssh ssh = c->ssh;
3050
3051 if (ssh->version == 1) {
5471d09a 3052 if (c->v.v1.throttling && bufsize < SSH1_BUFFER_LIMIT) {
3053 c->v.v1.throttling = 0;
51470298 3054 ssh1_throttle(ssh, -1);
5471d09a 3055 }
3056 } else {
3057 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
783415f8 3058 }
9c964e85 3059}
3060
51470298 3061static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
32874aea 3062{
51470298 3063 crBegin(ssh->ssh1_protocol_crstate);
fb09bf1c 3064
3065 random_init();
3066
51470298 3067 while (!do_ssh1_login(ssh, in, inlen, ispkt)) {
fb09bf1c 3068 crReturnV;
85ee8208 3069 }
51470298 3070 if (ssh->state == SSH_STATE_CLOSED)
32874aea 3071 crReturnV;
fb09bf1c 3072
86916870 3073 if (ssh->cfg.agentfwd && agent_exists()) {
32874aea 3074 logevent("Requesting agent forwarding");
51470298 3075 send_packet(ssh, SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
32874aea 3076 do {
3077 crReturnV;
3078 } while (!ispkt);
51470298 3079 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3080 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
6b5cf8b4 3081 bombout(("Protocol confusion"));
32874aea 3082 crReturnV;
51470298 3083 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
32874aea 3084 logevent("Agent forwarding refused");
3085 } else {
3086 logevent("Agent forwarding enabled");
51470298 3087 ssh->agentfwd_enabled = TRUE;
db7d555c 3088 }
dacbd0e8 3089 }
3090
86916870 3091 if (ssh->cfg.x11_forward) {
32874aea 3092 char proto[20], data[64];
3093 logevent("Requesting X11 forwarding");
302121de 3094 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
86916870 3095 data, sizeof(data), ssh->cfg.x11_auth);
3096 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
51470298 3097 if (ssh->v1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) {
3098 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
32874aea 3099 PKT_STR, proto, PKT_STR, data,
86916870 3100 PKT_INT, x11_get_screen_number(ssh->cfg.x11_display),
421d6835 3101 PKT_END);
32874aea 3102 } else {
51470298 3103 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
32874aea 3104 PKT_STR, proto, PKT_STR, data, PKT_END);
3105 }
3106 do {
3107 crReturnV;
3108 } while (!ispkt);
51470298 3109 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3110 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
6b5cf8b4 3111 bombout(("Protocol confusion"));
32874aea 3112 crReturnV;
51470298 3113 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
32874aea 3114 logevent("X11 forwarding refused");
3115 } else {
3116 logevent("X11 forwarding enabled");
51470298 3117 ssh->X11_fwd_enabled = TRUE;
9c964e85 3118 }
3119 }
3120
d74d141c 3121 {
9bf696b1 3122 char type;
d74d141c 3123 int n;
a4fc0d74 3124 int sport,dport,sserv,dserv;
6ee9b735 3125 char sports[256], dports[256], saddr[256], host[256];
d74d141c 3126
51470298 3127 ssh->rportfwds = newtree234(ssh_rportcmp_ssh1);
d74d141c 3128 /* Add port forwardings. */
86916870 3129 ssh->portfwd_strptr = ssh->cfg.portfwd;
51470298 3130 while (*ssh->portfwd_strptr) {
3131 type = *ssh->portfwd_strptr++;
6ee9b735 3132 saddr[0] = '\0';
d74d141c 3133 n = 0;
6ee9b735 3134 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != '\t') {
3135 if (*ssh->portfwd_strptr == ':') {
3136 /*
3137 * We've seen a colon in the middle of the
3138 * source port number. This means that
3139 * everything we've seen until now is the
3140 * source _address_, so we'll move it into
3141 * saddr and start sports from the beginning
3142 * again.
3143 */
3144 ssh->portfwd_strptr++;
3145 sports[n] = '\0';
3146 strcpy(saddr, sports);
3147 n = 0;
3148 }
3149 if (n < 255) sports[n++] = *ssh->portfwd_strptr++;
3150 }
d74d141c 3151 sports[n] = 0;
820ebe3b 3152 if (type != 'D') {
3153 if (*ssh->portfwd_strptr == '\t')
3154 ssh->portfwd_strptr++;
3155 n = 0;
3156 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != ':') {
3157 if (n < 255) host[n++] = *ssh->portfwd_strptr++;
3158 }
3159 host[n] = 0;
3160 if (*ssh->portfwd_strptr == ':')
3161 ssh->portfwd_strptr++;
3162 n = 0;
3163 while (*ssh->portfwd_strptr) {
3164 if (n < 255) dports[n++] = *ssh->portfwd_strptr++;
3165 }
3166 dports[n] = 0;
51470298 3167 ssh->portfwd_strptr++;
820ebe3b 3168 dport = atoi(dports);
3169 dserv = 0;
3170 if (dport == 0) {
3171 dserv = 1;
3172 dport = net_service_lookup(dports);
3173 if (!dport) {
3174 logeventf(ssh, "Service lookup failed for"
3175 " destination port \"%s\"", dports);
3176 }
a4fc0d74 3177 }
820ebe3b 3178 } else {
3179 while (*ssh->portfwd_strptr) ssh->portfwd_strptr++;
52893a36 3180 dport = -1;
a4fc0d74 3181 }
d74d141c 3182 sport = atoi(sports);
a4fc0d74 3183 sserv = 0;
3184 if (sport == 0) {
3185 sserv = 1;
68a49acb 3186 sport = net_service_lookup(sports);
3187 if (!sport) {
57356d63 3188 logeventf(ssh, "Service lookup failed for source"
3189 " port \"%s\"", sports);
a4fc0d74 3190 }
3191 }
d74d141c 3192 if (sport && dport) {
3193 if (type == 'L') {
6ee9b735 3194 pfd_addforward(host, dport, *saddr ? saddr : NULL,
e8fa8f62 3195 sport, ssh, &ssh->cfg);
6ee9b735 3196 logeventf(ssh, "Local port %.*s%.*s%.*s%.*s%d%.*s"
3197 " forwarding to %s:%.*s%.*s%d%.*s",
3198 (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
3199 (int)(*saddr?1:0), ":",
57356d63 3200 (int)(sserv ? strlen(sports) : 0), sports,
3201 sserv, "(", sport, sserv, ")",
3202 host,
3203 (int)(dserv ? strlen(dports) : 0), dports,
3204 dserv, "(", dport, dserv, ")");
820ebe3b 3205 } else if (type == 'D') {
3206 pfd_addforward(NULL, -1, *saddr ? saddr : NULL,
3207 sport, ssh, &ssh->cfg);
3208 logeventf(ssh, "Local port %.*s%.*s%.*s%.*s%d%.*s"
3209 " doing SOCKS dynamic forwarding",
3210 (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
3211 (int)(*saddr?1:0), ":",
3212 (int)(sserv ? strlen(sports) : 0), sports,
3213 sserv, "(", sport, sserv, ")");
d74d141c 3214 } else {
3215 struct ssh_rportfwd *pf;
3d88e64d 3216 pf = snew(struct ssh_rportfwd);
bc240b21 3217 strcpy(pf->dhost, host);
3218 pf->dport = dport;
6ee9b735 3219 if (saddr) {
3220 logeventf(ssh,
3221 "SSH1 cannot handle source address spec \"%s:%d\"; ignoring",
3222 saddr, sport);
3223 }
51470298 3224 if (add234(ssh->rportfwds, pf) != pf) {
57356d63 3225 logeventf(ssh,
3226 "Duplicate remote port forwarding to %s:%d",
3227 host, dport);
bc240b21 3228 sfree(pf);
d74d141c 3229 } else {
57356d63 3230 logeventf(ssh, "Requesting remote port %.*s%.*s%d%.*s"
3231 " forward to %s:%.*s%.*s%d%.*s",
3232 (int)(sserv ? strlen(sports) : 0), sports,
3233 sserv, "(", sport, sserv, ")",
3234 host,
3235 (int)(dserv ? strlen(dports) : 0), dports,
3236 dserv, "(", dport, dserv, ")");
51470298 3237 send_packet(ssh, SSH1_CMSG_PORT_FORWARD_REQUEST,
d74d141c 3238 PKT_INT, sport,
3239 PKT_STR, host,
3240 PKT_INT, dport,
3241 PKT_END);
9bf696b1 3242 do {
3243 crReturnV;
3244 } while (!ispkt);
51470298 3245 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3246 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
6b5cf8b4 3247 bombout(("Protocol confusion"));
9bf696b1 3248 crReturnV;
51470298 3249 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
3250 c_write_str(ssh, "Server refused port"
3251 " forwarding\r\n");
9bf696b1 3252 }
3253 logevent("Remote port forwarding enabled");
d74d141c 3254 }
3255 }
3256 }
3257 }
3258 }
3259
86916870 3260 if (!ssh->cfg.nopty) {
51470298 3261 send_packet(ssh, SSH1_CMSG_REQUEST_PTY,
86916870 3262 PKT_STR, ssh->cfg.termtype,
51470298 3263 PKT_INT, ssh->term_height,
3264 PKT_INT, ssh->term_width,
32874aea 3265 PKT_INT, 0, PKT_INT, 0, PKT_CHAR, 0, PKT_END);
51470298 3266 ssh->state = SSH_STATE_INTERMED;
32874aea 3267 do {
3268 crReturnV;
3269 } while (!ispkt);
51470298 3270 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3271 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
6b5cf8b4 3272 bombout(("Protocol confusion"));
32874aea 3273 crReturnV;
51470298 3274 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
3275 c_write_str(ssh, "Server refused to allocate pty\r\n");
3276 ssh->editing = ssh->echoing = 1;
32874aea 3277 }
c5e9c988 3278 logevent("Allocated pty");
0965bee0 3279 } else {
51470298 3280 ssh->editing = ssh->echoing = 1;
374330e2 3281 }
3282
86916870 3283 if (ssh->cfg.compression) {
51470298 3284 send_packet(ssh, SSH1_CMSG_REQUEST_COMPRESSION, PKT_INT, 6, PKT_END);
32874aea 3285 do {
3286 crReturnV;
3287 } while (!ispkt);
51470298 3288 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3289 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
6b5cf8b4 3290 bombout(("Protocol confusion"));
32874aea 3291 crReturnV;
51470298 3292 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
3293 c_write_str(ssh, "Server refused to compress\r\n");
32874aea 3294 }
4ba9b64b 3295 logevent("Started compression");
51470298 3296 ssh->v1_compressing = TRUE;
5366aed8 3297 ssh->cs_comp_ctx = zlib_compress_init();
3298 logevent("Initialised zlib (RFC1950) compression");
3299 ssh->sc_comp_ctx = zlib_decompress_init();
3300 logevent("Initialised zlib (RFC1950) decompression");
4ba9b64b 3301 }
3302
fd5e5847 3303 /*
3304 * Start the shell or command.
3305 *
3306 * Special case: if the first-choice command is an SSH2
3307 * subsystem (hence not usable here) and the second choice
3308 * exists, we fall straight back to that.
3309 */
3310 {
86916870 3311 char *cmd = ssh->cfg.remote_cmd_ptr;
fd5e5847 3312
86916870 3313 if (ssh->cfg.ssh_subsys && ssh->cfg.remote_cmd_ptr2) {
3314 cmd = ssh->cfg.remote_cmd_ptr2;
51470298 3315 ssh->fallback_cmd = TRUE;
fd5e5847 3316 }
3317 if (*cmd)
51470298 3318 send_packet(ssh, SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END);
fd5e5847 3319 else
51470298 3320 send_packet(ssh, SSH1_CMSG_EXEC_SHELL, PKT_END);
fd5e5847 3321 logevent("Started session");
3322 }
374330e2 3323
51470298 3324 ssh->state = SSH_STATE_SESSION;
3325 if (ssh->size_needed)
3326 ssh_size(ssh, ssh->term_width, ssh->term_height);
3327 if (ssh->eof_needed)
3328 ssh_special(ssh, TS_EOF);
374330e2 3329
b9d7bcad 3330 if (ssh->ldisc)
3331 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
51470298 3332 ssh->send_ok = 1;
3333 ssh->channels = newtree234(ssh_channelcmp);
374330e2 3334 while (1) {
3335 crReturnV;
3336 if (ispkt) {
51470298 3337 if (ssh->pktin.type == SSH1_SMSG_STDOUT_DATA ||
3338 ssh->pktin.type == SSH1_SMSG_STDERR_DATA) {
3339 long len = GET_32BIT(ssh->pktin.body);
5471d09a 3340 int bufsize =
51470298 3341 from_backend(ssh->frontend,
3342 ssh->pktin.type == SSH1_SMSG_STDERR_DATA,
d8baa528 3343 (char *)(ssh->pktin.body) + 4, len);
51470298 3344 if (!ssh->v1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
3345 ssh->v1_stdout_throttling = 1;
3346 ssh1_throttle(ssh, +1);
5471d09a 3347 }
51470298 3348 } else if (ssh->pktin.type == SSH1_MSG_DISCONNECT) {
3bb2f322 3349 ssh_closing((Plug)ssh, NULL, 0, 0);
c5e9c988 3350 logevent("Received disconnect request");
32874aea 3351 crReturnV;
51470298 3352 } else if (ssh->pktin.type == SSH1_SMSG_X11_OPEN) {
32874aea 3353 /* Remote side is trying to open a channel to talk to our
3354 * X-Server. Give them back a local channel number. */
3355 struct ssh_channel *c;
9c964e85 3356
3357 logevent("Received X11 connect request");
3358 /* Refuse if X11 forwarding is disabled. */
51470298 3359 if (!ssh->X11_fwd_enabled) {
3360 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
3361 PKT_INT, GET_32BIT(ssh->pktin.body), PKT_END);
9c964e85 3362 logevent("Rejected X11 connect request");
3363 } else {
3d88e64d 3364 c = snew(struct ssh_channel);
51470298 3365 c->ssh = ssh;
9c964e85 3366
86916870 3367 if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
e8fa8f62 3368 ssh->x11auth, NULL, -1, &ssh->cfg) != NULL) {
32874aea 3369 logevent("opening X11 forward connection failed");
3370 sfree(c);
51470298 3371 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
3372 PKT_INT, GET_32BIT(ssh->pktin.body),
32874aea 3373 PKT_END);
9c964e85 3374 } else {
32874aea 3375 logevent
3376 ("opening X11 forward connection succeeded");
51470298 3377 c->remoteid = GET_32BIT(ssh->pktin.body);
3378 c->localid = alloc_channel_id(ssh);
32874aea 3379 c->closes = 0;
5471d09a 3380 c->v.v1.throttling = 0;
32874aea 3381 c->type = CHAN_X11; /* identify channel type */
51470298 3382 add234(ssh->channels, c);
3383 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
32874aea 3384 PKT_INT, c->remoteid, PKT_INT,
3385 c->localid, PKT_END);
3386 logevent("Opened X11 forward channel");
9c964e85 3387 }
3388 }
51470298 3389 } else if (ssh->pktin.type == SSH1_SMSG_AGENT_OPEN) {
32874aea 3390 /* Remote side is trying to open a channel to talk to our
3391 * agent. Give them back a local channel number. */
3392 struct ssh_channel *c;
db7d555c 3393
3394 /* Refuse if agent forwarding is disabled. */
51470298 3395 if (!ssh->agentfwd_enabled) {
3396 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
3397 PKT_INT, GET_32BIT(ssh->pktin.body), PKT_END);
db7d555c 3398 } else {
3d88e64d 3399 c = snew(struct ssh_channel);
51470298 3400 c->ssh = ssh;
3401 c->remoteid = GET_32BIT(ssh->pktin.body);
3402 c->localid = alloc_channel_id(ssh);
db7d555c 3403 c->closes = 0;
5471d09a 3404 c->v.v1.throttling = 0;
32874aea 3405 c->type = CHAN_AGENT; /* identify channel type */
db7d555c 3406 c->u.a.lensofar = 0;
51470298 3407 add234(ssh->channels, c);
3408 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
db7d555c 3409 PKT_INT, c->remoteid, PKT_INT, c->localid,
3410 PKT_END);
3411 }
51470298 3412 } else if (ssh->pktin.type == SSH1_MSG_PORT_OPEN) {
d74d141c 3413 /* Remote side is trying to open a channel to talk to a
3414 * forwarded port. Give them back a local channel number. */
3415 struct ssh_channel *c;
3416 struct ssh_rportfwd pf;
3417 int hostsize, port;
3418 char host[256], buf[1024];
3419 char *p, *h, *e;
3d88e64d 3420 c = snew(struct ssh_channel);
51470298 3421 c->ssh = ssh;
d74d141c 3422
51470298 3423 hostsize = GET_32BIT(ssh->pktin.body+4);
d8baa528 3424 for (h = host, p = (char *)(ssh->pktin.body+8);
3425 hostsize != 0; hostsize--) {
d74d141c 3426 if (h+1 < host+sizeof(host))
3427 *h++ = *p;
95bc8819 3428 p++;
d74d141c 3429 }
3430 *h = 0;
3431 port = GET_32BIT(p);
3432
bc240b21 3433 strcpy(pf.dhost, host);
3434 pf.dport = port;
d74d141c 3435
51470298 3436 if (find234(ssh->rportfwds, &pf, NULL) == NULL) {
d74d141c 3437 sprintf(buf, "Rejected remote port open request for %s:%d",
3438 host, port);
3439 logevent(buf);
51470298 3440 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
3441 PKT_INT, GET_32BIT(ssh->pktin.body), PKT_END);
d74d141c 3442 } else {
3443 sprintf(buf, "Received remote port open request for %s:%d",
3444 host, port);
3445 logevent(buf);
e8fa8f62 3446 e = pfd_newconnect(&c->u.pfd.s, host, port, c, &ssh->cfg);
d74d141c 3447 if (e != NULL) {
3448 char buf[256];
3449 sprintf(buf, "Port open failed: %s", e);
3450 logevent(buf);
3451 sfree(c);
51470298 3452 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
3453 PKT_INT, GET_32BIT(ssh->pktin.body),
d74d141c 3454 PKT_END);
3455 } else {
51470298 3456 c->remoteid = GET_32BIT(ssh->pktin.body);
3457 c->localid = alloc_channel_id(ssh);
d74d141c 3458 c->closes = 0;
5471d09a 3459 c->v.v1.throttling = 0;
d74d141c 3460 c->type = CHAN_SOCKDATA; /* identify channel type */
51470298 3461 add234(ssh->channels, c);
3462 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
d74d141c 3463 PKT_INT, c->remoteid, PKT_INT,
3464 c->localid, PKT_END);
3465 logevent("Forwarded port opened successfully");
3466 }
3467 }
3468
51470298 3469 } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_OPEN_CONFIRMATION) {
3470 unsigned int remoteid = GET_32BIT(ssh->pktin.body);
3471 unsigned int localid = GET_32BIT(ssh->pktin.body+4);
bc240b21 3472 struct ssh_channel *c;
3473
51470298 3474 c = find234(ssh->channels, &remoteid, ssh_channelfind);
bc240b21 3475 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
3476 c->remoteid = localid;
3477 c->type = CHAN_SOCKDATA;
7781f316 3478 c->v.v1.throttling = 0;
bc240b21 3479 pfd_confirm(c->u.pfd.s);
3480 }
d74d141c 3481
4ed34d25 3482 if (c && c->closes) {
3483 /*
3484 * We have a pending close on this channel,
3485 * which we decided on before the server acked
3486 * the channel open. So now we know the
3487 * remoteid, we can close it again.
3488 */
51470298 3489 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE,
3490 PKT_INT, c->remoteid, PKT_END);
4ed34d25 3491 }
3492
51470298 3493 } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_OPEN_FAILURE) {
3494 unsigned int remoteid = GET_32BIT(ssh->pktin.body);
724cface 3495 struct ssh_channel *c;
3496
51470298 3497 c = find234(ssh->channels, &remoteid, ssh_channelfind);
724cface 3498 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
3499 logevent("Forwarded connection refused by server");
3500 pfd_close(c->u.pfd.s);
51470298 3501 del234(ssh->channels, c);
724cface 3502 sfree(c);
3503 }
3504
51470298 3505 } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE ||
3506 ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) {
32874aea 3507 /* Remote side closes a channel. */
51470298 3508 unsigned i = GET_32BIT(ssh->pktin.body);
32874aea 3509 struct ssh_channel *c;
51470298 3510 c = find234(ssh->channels, &i, ssh_channelfind);
d0d844c1 3511 if (c && ((int)c->remoteid) != -1) {
32874aea 3512 int closetype;
3513 closetype =
51470298 3514 (ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
0357890f 3515
783415f8 3516 if ((c->closes == 0) && (c->type == CHAN_X11)) {
d74d141c 3517 logevent("Forwarded X11 connection terminated");
9c964e85 3518 assert(c->u.x11.s != NULL);
3519 x11_close(c->u.x11.s);
3520 c->u.x11.s = NULL;
3521 }
d74d141c 3522 if ((c->closes == 0) && (c->type == CHAN_SOCKDATA)) {
3523 logevent("Forwarded port closed");
3524 assert(c->u.pfd.s != NULL);
3525 pfd_close(c->u.pfd.s);
3526 c->u.pfd.s = NULL;
3527 }
0357890f 3528
3529 c->closes |= (closetype << 2); /* seen this message */
3530 if (!(c->closes & closetype)) {
51470298 3531 send_packet(ssh, ssh->pktin.type, PKT_INT, c->remoteid,
0357890f 3532 PKT_END);
3533 c->closes |= closetype; /* sent it too */
3534 }
3535
3536 if (c->closes == 15) {
51470298 3537 del234(ssh->channels, c);
32874aea 3538 sfree(c);
3539 }
d0d844c1 3540 } else {
6b5cf8b4 3541 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
51470298 3542 ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE ? "" :
d0d844c1 3543 "_CONFIRMATION", c ? "half-open" : "nonexistent",
3544 i));
32874aea 3545 }
51470298 3546 } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_DATA) {
32874aea 3547 /* Data sent down one of our channels. */
51470298 3548 int i = GET_32BIT(ssh->pktin.body);
3549 int len = GET_32BIT(ssh->pktin.body + 4);
3550 unsigned char *p = ssh->pktin.body + 8;
32874aea 3551 struct ssh_channel *c;
51470298 3552 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 3553 if (c) {
5471d09a 3554 int bufsize;
32874aea 3555 switch (c->type) {
3556 case CHAN_X11:
d8baa528 3557 bufsize = x11_send(c->u.x11.s, (char *)p, len);
9c964e85 3558 break;
d74d141c 3559 case CHAN_SOCKDATA:
d8baa528 3560 bufsize = pfd_send(c->u.pfd.s, (char *)p, len);
bc240b21 3561 break;
32874aea 3562 case CHAN_AGENT:
3563 /* Data for an agent message. Buffer it. */
3564 while (len > 0) {
3565 if (c->u.a.lensofar < 4) {
3566 int l = min(4 - c->u.a.lensofar, len);
3567 memcpy(c->u.a.msglen + c->u.a.lensofar, p,
3568 l);
3569 p += l;
3570 len -= l;
3571 c->u.a.lensofar += l;
3572 }
3573 if (c->u.a.lensofar == 4) {
3574 c->u.a.totallen =
3575 4 + GET_32BIT(c->u.a.msglen);
3d88e64d 3576 c->u.a.message = snewn(c->u.a.totallen,
3577 unsigned char);
32874aea 3578 memcpy(c->u.a.message, c->u.a.msglen, 4);
3579 }
3580 if (c->u.a.lensofar >= 4 && len > 0) {
3581 int l =
3582 min(c->u.a.totallen - c->u.a.lensofar,
3583 len);
3584 memcpy(c->u.a.message + c->u.a.lensofar, p,
3585 l);
3586 p += l;
3587 len -= l;
3588 c->u.a.lensofar += l;
3589 }
3590 if (c->u.a.lensofar == c->u.a.totallen) {
3591 void *reply, *sentreply;
3592 int replylen;
3593 agent_query(c->u.a.message,
3594 c->u.a.totallen, &reply,
3595 &replylen);
3596 if (reply)
3597 sentreply = reply;
3598 else {
3599 /* Fake SSH_AGENT_FAILURE. */
3600 sentreply = "\0\0\0\1\5";
3601 replylen = 5;
3602 }
51470298 3603 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
32874aea 3604 PKT_INT, c->remoteid,
3605 PKT_INT, replylen,
3606 PKT_DATA, sentreply, replylen,
3607 PKT_END);
3608 if (reply)
3609 sfree(reply);
3610 sfree(c->u.a.message);
3611 c->u.a.lensofar = 0;
3612 }
3613 }
5471d09a 3614 bufsize = 0; /* agent channels never back up */
32874aea 3615 break;
3616 }
90347b95 3617 if (!c->v.v1.throttling && bufsize > SSH1_BUFFER_LIMIT) {
5471d09a 3618 c->v.v1.throttling = 1;
51470298 3619 ssh1_throttle(ssh, +1);
5471d09a 3620 }
32874aea 3621 }
51470298 3622 } else if (ssh->pktin.type == SSH1_SMSG_SUCCESS) {
972a41c8 3623 /* may be from EXEC_SHELL on some servers */
51470298 3624 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
972a41c8 3625 /* may be from EXEC_SHELL on some servers
374330e2 3626 * if no pty is available or in other odd cases. Ignore */
51470298 3627 } else if (ssh->pktin.type == SSH1_SMSG_EXIT_STATUS) {
d8d6c7e5 3628 char buf[100];
51470298 3629 ssh->exitcode = GET_32BIT(ssh->pktin.body);
d8d6c7e5 3630 sprintf(buf, "Server sent command exit status %d",
51470298 3631 ssh->exitcode);
d8d6c7e5 3632 logevent(buf);
51470298 3633 send_packet(ssh, SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
4252c9cc 3634 /*
3635 * In case `helpful' firewalls or proxies tack
3636 * extra human-readable text on the end of the
3637 * session which we might mistake for another
3638 * encrypted packet, we close the session once
3639 * we've sent EXIT_CONFIRMATION.
3640 */
3bb2f322 3641 ssh_closing((Plug)ssh, NULL, 0, 0);
4252c9cc 3642 crReturnV;
374330e2 3643 } else {
6b5cf8b4 3644 bombout(("Strange packet received: type %d", ssh->pktin.type));
32874aea 3645 crReturnV;
374330e2 3646 }
3647 } else {
8df7a775 3648 while (inlen > 0) {
3649 int len = min(inlen, 512);
51470298 3650 send_packet(ssh, SSH1_CMSG_STDIN_DATA,
8df7a775 3651 PKT_INT, len, PKT_DATA, in, len, PKT_END);
3652 in += len;
3653 inlen -= len;
3654 }
374330e2 3655 }
3656 }
3657
3658 crFinishV;
3659}
3660
3661/*
e5574168 3662 * Utility routine for decoding comma-separated strings in KEXINIT.
3663 */
32874aea 3664static int in_commasep_string(char *needle, char *haystack, int haylen)
3665{
57356d63 3666 int needlen;
3667 if (!needle || !haystack) /* protect against null pointers */
3668 return 0;
3669 needlen = strlen(needle);
e5574168 3670 while (1) {
32874aea 3671 /*
3672 * Is it at the start of the string?
3673 */
3674 if (haylen >= needlen && /* haystack is long enough */
3675 !memcmp(needle, haystack, needlen) && /* initial match */
3676 (haylen == needlen || haystack[needlen] == ',')
3677 /* either , or EOS follows */
3678 )
3679 return 1;
3680 /*
3681 * If not, search for the next comma and resume after that.
3682 * If no comma found, terminate.
3683 */
3684 while (haylen > 0 && *haystack != ',')
3685 haylen--, haystack++;
3686 if (haylen == 0)
3687 return 0;
3688 haylen--, haystack++; /* skip over comma itself */
e5574168 3689 }
3690}
3691
3692/*
d39f364a 3693 * SSH2 key creation method.
3694 */
d8baa528 3695static void ssh2_mkkey(Ssh ssh, Bignum K, unsigned char *H,
3696 unsigned char *sessid, char chr,
3697 unsigned char *keyspace)
32874aea 3698{
d39f364a 3699 SHA_State s;
3700 /* First 20 bytes. */
3701 SHA_Init(&s);
51470298 3702 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
088bde77 3703 sha_mpint(&s, K);
d39f364a 3704 SHA_Bytes(&s, H, 20);
3705 SHA_Bytes(&s, &chr, 1);
5e0d7cb8 3706 SHA_Bytes(&s, sessid, 20);
d39f364a 3707 SHA_Final(&s, keyspace);
3708 /* Next 20 bytes. */
3709 SHA_Init(&s);
51470298 3710 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
088bde77 3711 sha_mpint(&s, K);
d39f364a 3712 SHA_Bytes(&s, H, 20);
3713 SHA_Bytes(&s, keyspace, 20);
32874aea 3714 SHA_Final(&s, keyspace + 20);
d39f364a 3715}
3716
3717/*
7cca0d81 3718 * Handle the SSH2 transport layer.
e5574168 3719 */
51470298 3720static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
e5574168 3721{
51470298 3722 struct do_ssh2_transport_state {
3723 int nbits, pbits, warn;
3724 Bignum p, g, e, f, K;
3725 int kex_init_value, kex_reply_value;
3726 const struct ssh_mac **maclist;
3727 int nmacs;
3728 const struct ssh2_cipher *cscipher_tobe;
3729 const struct ssh2_cipher *sccipher_tobe;
3730 const struct ssh_mac *csmac_tobe;
3731 const struct ssh_mac *scmac_tobe;
3732 const struct ssh_compress *cscomp_tobe;
3733 const struct ssh_compress *sccomp_tobe;
3734 char *hostkeydata, *sigdata, *keystr, *fingerprint;
3735 int hostkeylen, siglen;
3736 void *hkey; /* actual host key */
3737 unsigned char exchange_hash[20];
3738 int n_preferred_ciphers;
3739 const struct ssh2_ciphers *preferred_ciphers[CIPHER_MAX];
3740 const struct ssh_compress *preferred_comp;
3741 int first_kex;
3742 };
3743 crState(do_ssh2_transport_state);
3744
3745 crBegin(ssh->do_ssh2_transport_crstate);
3746
3747 s->cscipher_tobe = s->sccipher_tobe = NULL;
3748 s->csmac_tobe = s->scmac_tobe = NULL;
3749 s->cscomp_tobe = s->sccomp_tobe = NULL;
3750
7cca0d81 3751 random_init();
51470298 3752 s->first_kex = 1;
e5574168 3753
51470298 3754 {
3755 int i;
3756 /*
3757 * Set up the preferred ciphers. (NULL => warn below here)
3758 */
3759 s->n_preferred_ciphers = 0;
3760 for (i = 0; i < CIPHER_MAX; i++) {
86916870 3761 switch (ssh->cfg.ssh_cipherlist[i]) {
51470298 3762 case CIPHER_BLOWFISH:
3763 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_blowfish;
3764 break;
3765 case CIPHER_DES:
86916870 3766 if (ssh->cfg.ssh2_des_cbc) {
51470298 3767 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_des;
3768 }
3769 break;
3770 case CIPHER_3DES:
3771 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_3des;
3772 break;
3773 case CIPHER_AES:
3774 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_aes;
3775 break;
3776 case CIPHER_WARN:
3777 /* Flag for later. Don't bother if it's the last in
3778 * the list. */
3779 if (i < CIPHER_MAX - 1) {
3780 s->preferred_ciphers[s->n_preferred_ciphers++] = NULL;
3781 }
3782 break;
ca20bfcf 3783 }
ca20bfcf 3784 }
5e8358ad 3785 }
ca20bfcf 3786
3787 /*
3788 * Set up preferred compression.
3789 */
86916870 3790 if (ssh->cfg.compression)
51470298 3791 s->preferred_comp = &ssh_zlib;
4ba9b64b 3792 else
51470298 3793 s->preferred_comp = &ssh_comp_none;
5e8358ad 3794
7591b9ff 3795 /*
3796 * Be prepared to work around the buggy MAC problem.
3797 */
51470298 3798 if (ssh->remote_bugs & BUG_SSH2_HMAC)
3799 s->maclist = buggymacs, s->nmacs = lenof(buggymacs);
7591b9ff 3800 else
51470298 3801 s->maclist = macs, s->nmacs = lenof(macs);
7591b9ff 3802
32874aea 3803 begin_key_exchange:
51470298 3804 {
3805 int i, j, cipherstr_started;
3806
3807 /*
3808 * Construct and send our key exchange packet.
3809 */
3810 ssh2_pkt_init(ssh, SSH2_MSG_KEXINIT);
3811 for (i = 0; i < 16; i++)
3812 ssh2_pkt_addbyte(ssh, (unsigned char) random_byte());
3813 /* List key exchange algorithms. */
3814 ssh2_pkt_addstring_start(ssh);
3815 for (i = 0; i < lenof(kex_algs); i++) {
3816 if (kex_algs[i] == &ssh_diffiehellman_gex &&
3817 (ssh->remote_bugs & BUG_SSH2_DH_GEX))
3818 continue;
3819 ssh2_pkt_addstring_str(ssh, kex_algs[i]->name);
3820 if (i < lenof(kex_algs) - 1)
3821 ssh2_pkt_addstring_str(ssh, ",");
32874aea 3822 }
51470298 3823 /* List server host key algorithms. */
3824 ssh2_pkt_addstring_start(ssh);
3825 for (i = 0; i < lenof(hostkey_algs); i++) {
3826 ssh2_pkt_addstring_str(ssh, hostkey_algs[i]->name);
3827 if (i < lenof(hostkey_algs) - 1)
3828 ssh2_pkt_addstring_str(ssh, ",");
32874aea 3829 }
51470298 3830 /* List client->server encryption algorithms. */
3831 ssh2_pkt_addstring_start(ssh);
3832 cipherstr_started = 0;
3833 for (i = 0; i < s->n_preferred_ciphers; i++) {
3834 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
3835 if (!c) continue; /* warning flag */
3836 for (j = 0; j < c->nciphers; j++) {
3837 if (cipherstr_started)
3838 ssh2_pkt_addstring_str(ssh, ",");
3839 ssh2_pkt_addstring_str(ssh, c->list[j]->name);
3840 cipherstr_started = 1;
3841 }
3842 }
3843 /* List server->client encryption algorithms. */
3844 ssh2_pkt_addstring_start(ssh);
3845 cipherstr_started = 0;
3846 for (i = 0; i < s->n_preferred_ciphers; i++) {
3847 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
3848 if (!c) continue; /* warning flag */
3849 for (j = 0; j < c->nciphers; j++) {
3850 if (cipherstr_started)
3851 ssh2_pkt_addstring_str(ssh, ",");
3852 ssh2_pkt_addstring_str(ssh, c->list[j]->name);
3853 cipherstr_started = 1;
3854 }
3855 }
3856 /* List client->server MAC algorithms. */
3857 ssh2_pkt_addstring_start(ssh);
3858 for (i = 0; i < s->nmacs; i++) {
3859 ssh2_pkt_addstring_str(ssh, s->maclist[i]->name);
3860 if (i < s->nmacs - 1)
3861 ssh2_pkt_addstring_str(ssh, ",");
3862 }
3863 /* List server->client MAC algorithms. */
3864 ssh2_pkt_addstring_start(ssh);
3865 for (i = 0; i < s->nmacs; i++) {
3866 ssh2_pkt_addstring_str(ssh, s->maclist[i]->name);
3867 if (i < s->nmacs - 1)
3868 ssh2_pkt_addstring_str(ssh, ",");
3869 }
3870 /* List client->server compression algorithms. */
3871 ssh2_pkt_addstring_start(ssh);
3872 for (i = 0; i < lenof(compressions) + 1; i++) {
3873 const struct ssh_compress *c =
3874 i == 0 ? s->preferred_comp : compressions[i - 1];
3875 ssh2_pkt_addstring_str(ssh, c->name);
3876 if (i < lenof(compressions))
3877 ssh2_pkt_addstring_str(ssh, ",");
3878 }
3879 /* List server->client compression algorithms. */
3880 ssh2_pkt_addstring_start(ssh);
3881 for (i = 0; i < lenof(compressions) + 1; i++) {
3882 const struct ssh_compress *c =
3883 i == 0 ? s->preferred_comp : compressions[i - 1];
3884 ssh2_pkt_addstring_str(ssh, c->name);
3885 if (i < lenof(compressions))
3886 ssh2_pkt_addstring_str(ssh, ",");
3887 }
3888 /* List client->server languages. Empty list. */
3889 ssh2_pkt_addstring_start(ssh);
3890 /* List server->client languages. Empty list. */
3891 ssh2_pkt_addstring_start(ssh);
3892 /* First KEX packet does _not_ follow, because we're not that brave. */
3893 ssh2_pkt_addbool(ssh, FALSE);
3894 /* Reserved. */
3895 ssh2_pkt_adduint32(ssh, 0);
e5574168 3896 }
0db56f73 3897
51470298 3898 ssh->exhash = ssh->exhashbase;
3899 sha_string(&ssh->exhash, ssh->pktout.data + 5, ssh->pktout.length - 5);
0db56f73 3900
51470298 3901 ssh2_pkt_send(ssh);
e5574168 3902
32874aea 3903 if (!ispkt)
3904 crWaitUntil(ispkt);
57356d63 3905 if (ssh->pktin.length > 5)
3906 sha_string(&ssh->exhash, ssh->pktin.data + 5, ssh->pktin.length - 5);
e5574168 3907
3908 /*
3909 * Now examine the other side's KEXINIT to see what we're up
3910 * to.
3911 */
51470298 3912 {
3913 char *str;
3914 int i, j, len;
3915
3916 if (ssh->pktin.type != SSH2_MSG_KEXINIT) {
6b5cf8b4 3917 bombout(("expected key exchange packet from server"));
51470298 3918 crReturn(0);
32874aea 3919 }
51470298 3920 ssh->kex = NULL;
3921 ssh->hostkey = NULL;
3922 s->cscipher_tobe = NULL;
3923 s->sccipher_tobe = NULL;
3924 s->csmac_tobe = NULL;
3925 s->scmac_tobe = NULL;
3926 s->cscomp_tobe = NULL;
3927 s->sccomp_tobe = NULL;
3928 ssh->pktin.savedpos += 16; /* skip garbage cookie */
3929 ssh2_pkt_getstring(ssh, &str, &len); /* key exchange algorithms */
3930 for (i = 0; i < lenof(kex_algs); i++) {
3931 if (kex_algs[i] == &ssh_diffiehellman_gex &&
3932 (ssh->remote_bugs & BUG_SSH2_DH_GEX))
3933 continue;
3934 if (in_commasep_string(kex_algs[i]->name, str, len)) {
3935 ssh->kex = kex_algs[i];
3936 break;
3937 }
32874aea 3938 }
51470298 3939 ssh2_pkt_getstring(ssh, &str, &len); /* host key algorithms */
3940 for (i = 0; i < lenof(hostkey_algs); i++) {
3941 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
3942 ssh->hostkey = hostkey_algs[i];
3943 break;
3944 }
3945 }
3946 ssh2_pkt_getstring(ssh, &str, &len); /* client->server cipher */
3947 s->warn = 0;
3948 for (i = 0; i < s->n_preferred_ciphers; i++) {
3949 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
3950 if (!c) {
3951 s->warn = 1;
3952 } else {
3953 for (j = 0; j < c->nciphers; j++) {
3954 if (in_commasep_string(c->list[j]->name, str, len)) {
3955 s->cscipher_tobe = c->list[j];
3956 break;
3957 }
ca20bfcf 3958 }
32874aea 3959 }
51470298 3960 if (s->cscipher_tobe) {
3961 if (s->warn)
a8327734 3962 askcipher(ssh->frontend, s->cscipher_tobe->name, 1);
51470298 3963 break;
3964 }
32874aea 3965 }
51470298 3966 if (!s->cscipher_tobe) {
6b5cf8b4 3967 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
57356d63 3968 str ? str : "(null)"));
51470298 3969 crReturn(0);
ca20bfcf 3970 }
0ef8f407 3971
51470298 3972 ssh2_pkt_getstring(ssh, &str, &len); /* server->client cipher */
3973 s->warn = 0;
3974 for (i = 0; i < s->n_preferred_ciphers; i++) {
3975 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
3976 if (!c) {
3977 s->warn = 1;
3978 } else {
3979 for (j = 0; j < c->nciphers; j++) {
3980 if (in_commasep_string(c->list[j]->name, str, len)) {
3981 s->sccipher_tobe = c->list[j];
3982 break;
3983 }
ca20bfcf 3984 }
32874aea 3985 }
51470298 3986 if (s->sccipher_tobe) {
3987 if (s->warn)
a8327734 3988 askcipher(ssh->frontend, s->sccipher_tobe->name, 2);
51470298 3989 break;
3990 }
32874aea 3991 }
51470298 3992 if (!s->sccipher_tobe) {
6b5cf8b4 3993 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
57356d63 3994 str ? str : "(null)"));
51470298 3995 crReturn(0);
ca20bfcf 3996 }
0ef8f407 3997
51470298 3998 ssh2_pkt_getstring(ssh, &str, &len); /* client->server mac */
3999 for (i = 0; i < s->nmacs; i++) {
4000 if (in_commasep_string(s->maclist[i]->name, str, len)) {
4001 s->csmac_tobe = s->maclist[i];
4002 break;
4003 }
32874aea 4004 }
51470298 4005 ssh2_pkt_getstring(ssh, &str, &len); /* server->client mac */
4006 for (i = 0; i < s->nmacs; i++) {
4007 if (in_commasep_string(s->maclist[i]->name, str, len)) {
4008 s->scmac_tobe = s->maclist[i];
4009 break;
4010 }
32874aea 4011 }
51470298 4012 ssh2_pkt_getstring(ssh, &str, &len); /* client->server compression */
4013 for (i = 0; i < lenof(compressions) + 1; i++) {
4014 const struct ssh_compress *c =
4015 i == 0 ? s->preferred_comp : compressions[i - 1];
4016 if (in_commasep_string(c->name, str, len)) {
4017 s->cscomp_tobe = c;
4018 break;
4019 }
32874aea 4020 }
51470298 4021 ssh2_pkt_getstring(ssh, &str, &len); /* server->client compression */
4022 for (i = 0; i < lenof(compressions) + 1; i++) {
4023 const struct ssh_compress *c =
4024 i == 0 ? s->preferred_comp : compressions[i - 1];
4025 if (in_commasep_string(c->name, str, len)) {
4026 s->sccomp_tobe = c;
4027 break;
4028 }
32874aea 4029 }
e5574168 4030 }
e5574168 4031
4032 /*
7bd5a860 4033 * Work out the number of bits of key we will need from the key
4034 * exchange. We start with the maximum key length of either
4035 * cipher...
4036 */
4037 {
32874aea 4038 int csbits, scbits;
7bd5a860 4039
51470298 4040 csbits = s->cscipher_tobe->keylen;
4041 scbits = s->sccipher_tobe->keylen;
4042 s->nbits = (csbits > scbits ? csbits : scbits);
7bd5a860 4043 }
4044 /* The keys only have 160-bit entropy, since they're based on
4045 * a SHA-1 hash. So cap the key size at 160 bits. */
51470298 4046 if (s->nbits > 160)
4047 s->nbits = 160;
7bd5a860 4048
4049 /*
a92dd380 4050 * If we're doing Diffie-Hellman group exchange, start by
4051 * requesting a group.
e5574168 4052 */
51470298 4053 if (ssh->kex == &ssh_diffiehellman_gex) {
32874aea 4054 logevent("Doing Diffie-Hellman group exchange");
51470298 4055 ssh->pkt_ctx |= SSH2_PKTCTX_DHGEX;
32874aea 4056 /*
4057 * Work out how big a DH group we will need to allow that
4058 * much data.
7bd5a860 4059 */
51470298 4060 s->pbits = 512 << ((s->nbits - 1) / 64);
4061 ssh2_pkt_init(ssh, SSH2_MSG_KEX_DH_GEX_REQUEST);
4062 ssh2_pkt_adduint32(ssh, s->pbits);
4063 ssh2_pkt_send(ssh);
32874aea 4064
4065 crWaitUntil(ispkt);
51470298 4066 if (ssh->pktin.type != SSH2_MSG_KEX_DH_GEX_GROUP) {
6b5cf8b4 4067 bombout(("expected key exchange group packet from server"));
32874aea 4068 crReturn(0);
4069 }
51470298 4070 s->p = ssh2_pkt_getmp(ssh);
4071 s->g = ssh2_pkt_getmp(ssh);
27cd7fc2 4072 ssh->kex_ctx = dh_setup_group(s->p, s->g);
51470298 4073 s->kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
4074 s->kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY;
a92dd380 4075 } else {
51470298 4076 ssh->pkt_ctx |= SSH2_PKTCTX_DHGROUP1;
27cd7fc2 4077 ssh->kex_ctx = dh_setup_group1();
51470298 4078 s->kex_init_value = SSH2_MSG_KEXDH_INIT;
4079 s->kex_reply_value = SSH2_MSG_KEXDH_REPLY;
8d5de777 4080 }
e5574168 4081
a92dd380 4082 logevent("Doing Diffie-Hellman key exchange");
e5574168 4083 /*
a92dd380 4084 * Now generate and send e for Diffie-Hellman.
e5574168 4085 */
27cd7fc2 4086 s->e = dh_create_e(ssh->kex_ctx, s->nbits * 2);
51470298 4087 ssh2_pkt_init(ssh, s->kex_init_value);
4088 ssh2_pkt_addmp(ssh, s->e);
4089 ssh2_pkt_send(ssh);
e5574168 4090
4091 crWaitUntil(ispkt);
51470298 4092 if (ssh->pktin.type != s->kex_reply_value) {
6b5cf8b4 4093 bombout(("expected key exchange reply packet from server"));
32874aea 4094 crReturn(0);
7cca0d81 4095 }
51470298 4096 ssh2_pkt_getstring(ssh, &s->hostkeydata, &s->hostkeylen);
4097 s->f = ssh2_pkt_getmp(ssh);
4098 ssh2_pkt_getstring(ssh, &s->sigdata, &s->siglen);
e5574168 4099
27cd7fc2 4100 s->K = dh_find_K(ssh->kex_ctx, s->f);
e5574168 4101
51470298 4102 sha_string(&ssh->exhash, s->hostkeydata, s->hostkeylen);
4103 if (ssh->kex == &ssh_diffiehellman_gex) {
4104 sha_uint32(&ssh->exhash, s->pbits);
4105 sha_mpint(&ssh->exhash, s->p);
4106 sha_mpint(&ssh->exhash, s->g);
a92dd380 4107 }
51470298 4108 sha_mpint(&ssh->exhash, s->e);
4109 sha_mpint(&ssh->exhash, s->f);
4110 sha_mpint(&ssh->exhash, s->K);
4111 SHA_Final(&ssh->exhash, s->exchange_hash);
e5574168 4112
27cd7fc2 4113 dh_cleanup(ssh->kex_ctx);
fabd1805 4114 ssh->kex_ctx = NULL;
3709bfe9 4115
7cca0d81 4116#if 0
765c4200 4117 debug(("Exchange hash is:\n"));
51470298 4118 dmemdump(s->exchange_hash, 20);
7cca0d81 4119#endif
4120
51470298 4121 s->hkey = ssh->hostkey->newkey(s->hostkeydata, s->hostkeylen);
4122 if (!s->hkey ||
4123 !ssh->hostkey->verifysig(s->hkey, s->sigdata, s->siglen,
d8baa528 4124 (char *)s->exchange_hash, 20)) {
6b5cf8b4 4125 bombout(("Server's host key did not match the signature supplied"));
32874aea 4126 crReturn(0);
8d5de777 4127 }
e5574168 4128
4129 /*
7cca0d81 4130 * Authenticate remote host: verify host key. (We've already
4131 * checked the signature of the exchange hash.)
e5574168 4132 */
51470298 4133 s->keystr = ssh->hostkey->fmtkey(s->hkey);
4134 s->fingerprint = ssh->hostkey->fingerprint(s->hkey);
a8327734 4135 verify_ssh_host_key(ssh->frontend,
4136 ssh->savedhost, ssh->savedport, ssh->hostkey->keytype,
51470298 4137 s->keystr, s->fingerprint);
4138 if (s->first_kex) { /* don't bother logging this in rekeys */
5e0d7cb8 4139 logevent("Host key fingerprint is:");
51470298 4140 logevent(s->fingerprint);
5e0d7cb8 4141 }
51470298 4142 sfree(s->fingerprint);
4143 sfree(s->keystr);
4144 ssh->hostkey->freekey(s->hkey);
d39f364a 4145
4146 /*
7cca0d81 4147 * Send SSH2_MSG_NEWKEYS.
d39f364a 4148 */
51470298 4149 ssh2_pkt_init(ssh, SSH2_MSG_NEWKEYS);
4150 ssh2_pkt_send(ssh);
d39f364a 4151
4152 /*
8406eaf9 4153 * Expect SSH2_MSG_NEWKEYS from server.
4154 */
4155 crWaitUntil(ispkt);
51470298 4156 if (ssh->pktin.type != SSH2_MSG_NEWKEYS) {
6b5cf8b4 4157 bombout(("expected new-keys packet from server"));
8406eaf9 4158 crReturn(0);
4159 }
4160
4161 /*
d39f364a 4162 * Create and initialise session keys.
4163 */
371e569c 4164 if (ssh->cs_cipher_ctx)
4165 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
51470298 4166 ssh->cscipher = s->cscipher_tobe;
371e569c 4167 ssh->cs_cipher_ctx = ssh->cscipher->make_context();
e0e1a00d 4168
371e569c 4169 if (ssh->sc_cipher_ctx)
4170 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
51470298 4171 ssh->sccipher = s->sccipher_tobe;
371e569c 4172 ssh->sc_cipher_ctx = ssh->sccipher->make_context();
e0e1a00d 4173
4174 if (ssh->cs_mac_ctx)
4175 ssh->csmac->free_context(ssh->cs_mac_ctx);
51470298 4176 ssh->csmac = s->csmac_tobe;
e0e1a00d 4177 ssh->cs_mac_ctx = ssh->csmac->make_context();
4178
4179 if (ssh->sc_mac_ctx)
4180 ssh->scmac->free_context(ssh->sc_mac_ctx);
51470298 4181 ssh->scmac = s->scmac_tobe;
e0e1a00d 4182 ssh->sc_mac_ctx = ssh->scmac->make_context();
4183
5366aed8 4184 if (ssh->cs_comp_ctx)
4185 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
51470298 4186 ssh->cscomp = s->cscomp_tobe;
5366aed8 4187 ssh->cs_comp_ctx = ssh->cscomp->compress_init();
4188
4189 if (ssh->sc_comp_ctx)
4190 ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
51470298 4191 ssh->sccomp = s->sccomp_tobe;
5366aed8 4192 ssh->sc_comp_ctx = ssh->sccomp->decompress_init();
4193
d39f364a 4194 /*
5e0d7cb8 4195 * Set IVs after keys. Here we use the exchange hash from the
4196 * _first_ key exchange.
d39f364a 4197 */
51470298 4198 {
4199 unsigned char keyspace[40];
4200 if (s->first_kex)
4201 memcpy(ssh->v2_session_id, s->exchange_hash,
4202 sizeof(s->exchange_hash));
4203 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'C',keyspace);
371e569c 4204 ssh->cscipher->setkey(ssh->cs_cipher_ctx, keyspace);
51470298 4205 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'D',keyspace);
371e569c 4206 ssh->sccipher->setkey(ssh->sc_cipher_ctx, keyspace);
51470298 4207 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'A',keyspace);
371e569c 4208 ssh->cscipher->setiv(ssh->cs_cipher_ctx, keyspace);
51470298 4209 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'B',keyspace);
371e569c 4210 ssh->sccipher->setiv(ssh->sc_cipher_ctx, keyspace);
51470298 4211 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'E',keyspace);
e0e1a00d 4212 ssh->csmac->setkey(ssh->cs_mac_ctx, keyspace);
51470298 4213 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'F',keyspace);
e0e1a00d 4214 ssh->scmac->setkey(ssh->sc_mac_ctx, keyspace);
51470298 4215 }
57356d63 4216 logeventf(ssh, "Initialised %.200s client->server encryption",
4217 ssh->cscipher->text_name);
4218 logeventf(ssh, "Initialised %.200s server->client encryption",
4219 ssh->sccipher->text_name);
4220 if (ssh->cscomp->text_name)
4221 logeventf(ssh, "Initialised %s compression",
4222 ssh->cscomp->text_name);
4223 if (ssh->sccomp->text_name)
4224 logeventf(ssh, "Initialised %s decompression",
4225 ssh->sccomp->text_name);
d39f364a 4226
033b4cef 4227 /*
0db56f73 4228 * If this is the first key exchange phase, we must pass the
4229 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
4230 * wants to see it but because it will need time to initialise
4231 * itself before it sees an actual packet. In subsequent key
4232 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
4233 * it would only confuse the layer above.
4234 */
51470298 4235 if (!s->first_kex) {
32874aea 4236 crReturn(0);
0db56f73 4237 }
51470298 4238 s->first_kex = 0;
0db56f73 4239
4240 /*
7cca0d81 4241 * Now we're encrypting. Begin returning 1 to the protocol main
4242 * function so that other things can run on top of the
4243 * transport. If we ever see a KEXINIT, we must go back to the
4244 * start.
033b4cef 4245 */
51470298 4246 while (!(ispkt && ssh->pktin.type == SSH2_MSG_KEXINIT)) {
32874aea 4247 crReturn(1);
e96adf72 4248 }
5e0d7cb8 4249 logevent("Server initiated key re-exchange");
7cca0d81 4250 goto begin_key_exchange;
e5574168 4251
4252 crFinish(1);
4253}
4254
7cca0d81 4255/*
783415f8 4256 * Add data to an SSH2 channel output buffer.
4257 */
32874aea 4258static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
4259 int len)
4260{
5471d09a 4261 bufchain_add(&c->v.v2.outbuffer, buf, len);
783415f8 4262}
4263
4264/*
4265 * Attempt to send data on an SSH2 channel.
4266 */
5471d09a 4267static int ssh2_try_send(struct ssh_channel *c)
32874aea 4268{
51470298 4269 Ssh ssh = c->ssh;
4270
5471d09a 4271 while (c->v.v2.remwindow > 0 && bufchain_size(&c->v.v2.outbuffer) > 0) {
4272 int len;
4273 void *data;
4274 bufchain_prefix(&c->v.v2.outbuffer, &data, &len);
4275 if ((unsigned)len > c->v.v2.remwindow)
4276 len = c->v.v2.remwindow;
4277 if ((unsigned)len > c->v.v2.remmaxpkt)
4278 len = c->v.v2.remmaxpkt;
51470298 4279 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_DATA);
4280 ssh2_pkt_adduint32(ssh, c->remoteid);
4281 ssh2_pkt_addstring_start(ssh);
4282 ssh2_pkt_addstring_data(ssh, data, len);
4283 ssh2_pkt_send(ssh);
5471d09a 4284 bufchain_consume(&c->v.v2.outbuffer, len);
4285 c->v.v2.remwindow -= len;
4286 }
4287
4288 /*
4289 * After having sent as much data as we can, return the amount
4290 * still buffered.
4291 */
4292 return bufchain_size(&c->v.v2.outbuffer);
4293}
4294
4295/*
4296 * Potentially enlarge the window on an SSH2 channel.
4297 */
4298static void ssh2_set_window(struct ssh_channel *c, unsigned newwin)
4299{
51470298 4300 Ssh ssh = c->ssh;
4301
6b69f42e 4302 /*
4303 * Never send WINDOW_ADJUST for a channel that the remote side
4304 * already thinks it's closed; there's no point, since it won't
4305 * be sending any more data anyway.
4306 */
4307 if (c->closes != 0)
4308 return;
4309
5471d09a 4310 if (newwin > c->v.v2.locwindow) {
51470298 4311 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST);
4312 ssh2_pkt_adduint32(ssh, c->remoteid);
4313 ssh2_pkt_adduint32(ssh, newwin - c->v.v2.locwindow);
4314 ssh2_pkt_send(ssh);
5471d09a 4315 c->v.v2.locwindow = newwin;
783415f8 4316 }
4317}
4318
4319/*
7cca0d81 4320 * Handle the SSH2 userauth and connection layers.
4321 */
51470298 4322static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
7cca0d81 4323{
51470298 4324 struct do_ssh2_authconn_state {
4325 enum {
4326 AUTH_INVALID, AUTH_PUBLICKEY_AGENT, AUTH_PUBLICKEY_FILE,
4327 AUTH_PASSWORD,
4328 AUTH_KEYBOARD_INTERACTIVE
4329 } method;
4330 enum {
4331 AUTH_TYPE_NONE,
4332 AUTH_TYPE_PUBLICKEY,
4333 AUTH_TYPE_PUBLICKEY_OFFER_LOUD,
4334 AUTH_TYPE_PUBLICKEY_OFFER_QUIET,
4335 AUTH_TYPE_PASSWORD,
4336 AUTH_TYPE_KEYBOARD_INTERACTIVE,
4337 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
4338 } type;
4339 int gotit, need_pw, can_pubkey, can_passwd, can_keyb_inter;
4340 int tried_pubkey_config, tried_agent, tried_keyb_inter;
4341 int kbd_inter_running;
4342 int we_are_in;
4343 int num_prompts, curr_prompt, echo;
4344 char username[100];
4345 int got_username;
4346 char pwprompt[200];
4347 char password[100];
4348 void *publickey_blob;
4349 int publickey_bloblen;
4350 unsigned char request[5], *response, *p;
4351 int responselen;
4352 int keyi, nkeys;
4353 int authed;
4354 char *pkblob, *alg, *commentp;
4355 int pklen, alglen, commentlen;
4356 int siglen, retlen, len;
4357 char *q, *agentreq, *ret;
4358 int try_send;
4359 };
4360 crState(do_ssh2_authconn_state);
4361
4362 crBegin(ssh->do_ssh2_authconn_crstate);
e5574168 4363
7cca0d81 4364 /*
4365 * Request userauth protocol, and await a response to it.
4366 */
51470298 4367 ssh2_pkt_init(ssh, SSH2_MSG_SERVICE_REQUEST);
4368 ssh2_pkt_addstring(ssh, "ssh-userauth");
4369 ssh2_pkt_send(ssh);
7cca0d81 4370 crWaitUntilV(ispkt);
51470298 4371 if (ssh->pktin.type != SSH2_MSG_SERVICE_ACCEPT) {
6b5cf8b4 4372 bombout(("Server refused user authentication protocol"));
32874aea 4373 crReturnV;
8d5de777 4374 }
7cca0d81 4375
4376 /*
1408a877 4377 * We repeat this whole loop, including the username prompt,
4378 * until we manage a successful authentication. If the user
51470298 4379 * types the wrong _password_, they can be sent back to the
4380 * beginning to try another username, if this is configured on.
4381 * (If they specify a username in the config, they are never
4382 * asked, even if they do give a wrong password.)
1408a877 4383 *
4384 * I think this best serves the needs of
4385 *
4386 * - the people who have no configuration, no keys, and just
4387 * want to try repeated (username,password) pairs until they
4388 * type both correctly
4389 *
4390 * - people who have keys and configuration but occasionally
4391 * need to fall back to passwords
4392 *
4393 * - people with a key held in Pageant, who might not have
4394 * logged in to a particular machine before; so they want to
4395 * type a username, and then _either_ their key will be
4396 * accepted, _or_ they will type a password. If they mistype
4397 * the username they will want to be able to get back and
4398 * retype it!
7cca0d81 4399 */
51470298 4400 s->username[0] = '\0';
4401 s->got_username = FALSE;
1408a877 4402 do {
1408a877 4403 /*
4404 * Get a username.
4405 */
86916870 4406 if (s->got_username && !ssh->cfg.change_username) {
5bb641e1 4407 /*
4408 * We got a username last time round this loop, and
4409 * with change_username turned off we don't try to get
4410 * it again.
4411 */
86916870 4412 } else if ((flags & FLAG_INTERACTIVE) && !*ssh->cfg.username) {
c0a81592 4413 if (ssh_get_line && !ssh_getline_pw_only) {
32874aea 4414 if (!ssh_get_line("login as: ",
51470298 4415 s->username, sizeof(s->username), FALSE)) {
32874aea 4416 /*
4417 * get_line failed to get a username.
4418 * Terminate.
4419 */
4420 logevent("No username provided. Abandoning session.");
3bb2f322 4421 ssh_closing((Plug)ssh, NULL, 0, 0);
32874aea 4422 crReturnV;
4423 }
4424 } else {
51470298 4425 int ret; /* need not be saved across crReturn */
4426 c_write_str(ssh, "login as: ");
4427 ssh->send_ok = 1;
4428 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
0405e71f 4429 do {
32874aea 4430 crWaitUntilV(!ispkt);
51470298 4431 ret = process_userpass_input(ssh, in, inlen);
0405e71f 4432 } while (ret == 0);
4433 if (ret < 0)
4434 cleanup_exit(0);
4ca0c9d1 4435 c_write_str(ssh, "\r\n");
32874aea 4436 }
51470298 4437 s->username[strcspn(s->username, "\n\r")] = '\0';
7cca0d81 4438 } else {
57356d63 4439 char *stuff;
86916870 4440 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
51470298 4441 s->username[sizeof(s->username)-1] = '\0';
65a22376 4442 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
57356d63 4443 stuff = dupprintf("Using username \"%s\".\r\n", s->username);
51470298 4444 c_write_str(ssh, stuff);
57356d63 4445 sfree(stuff);
7cca0d81 4446 }
4447 }
51470298 4448 s->got_username = TRUE;
7cca0d81 4449
65a22376 4450 /*
1408a877 4451 * Send an authentication request using method "none": (a)
4452 * just in case it succeeds, and (b) so that we know what
4453 * authentication methods we can usefully try next.
65a22376 4454 */
51470298 4455 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4456
4457 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4458 ssh2_pkt_addstring(ssh, s->username);
4459 ssh2_pkt_addstring(ssh, "ssh-connection");/* service requested */
4460 ssh2_pkt_addstring(ssh, "none"); /* method */
4461 ssh2_pkt_send(ssh);
4462 s->type = AUTH_TYPE_NONE;
4463 s->gotit = FALSE;
4464 s->we_are_in = FALSE;
4465
4466 s->tried_pubkey_config = FALSE;
4467 s->tried_agent = FALSE;
4468 s->tried_keyb_inter = FALSE;
4469 s->kbd_inter_running = FALSE;
86916870 4470 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
9a30e26b 4471 if (!filename_is_null(ssh->cfg.keyfile)) {
231ee168 4472 int keytype;
6c6d9ed9 4473 logeventf(ssh, "Reading private key file \"%.150s\"",
4474 filename_to_str(&ssh->cfg.keyfile));
9a30e26b 4475 keytype = key_type(&ssh->cfg.keyfile);
51470298 4476 if (keytype == SSH_KEYTYPE_SSH2) {
4477 s->publickey_blob =
9a30e26b 4478 ssh2_userkey_loadpub(&ssh->cfg.keyfile, NULL,
51470298 4479 &s->publickey_bloblen);
4480 } else {
57356d63 4481 char *msgbuf;
c2ad7d0d 4482 logeventf(ssh, "Unable to use this key file (%s)",
a8327734 4483 key_type_to_str(keytype));
57356d63 4484 msgbuf = dupprintf("Unable to use key file \"%.150s\""
6c6d9ed9 4485 " (%s)\r\n",
4486 filename_to_str(&ssh->cfg.keyfile),
57356d63 4487 key_type_to_str(keytype));
51470298 4488 c_write_str(ssh, msgbuf);
57356d63 4489 sfree(msgbuf);
51470298 4490 s->publickey_blob = NULL;
231ee168 4491 }
396778f1 4492 } else
51470298 4493 s->publickey_blob = NULL;
65a22376 4494
1408a877 4495 while (1) {
4496 /*
4497 * Wait for the result of the last authentication request.
4498 */
51470298 4499 if (!s->gotit)
1408a877 4500 crWaitUntilV(ispkt);
51470298 4501 while (ssh->pktin.type == SSH2_MSG_USERAUTH_BANNER) {
32874aea 4502 char *banner;
4503 int size;
4504 /*
4505 * Don't show the banner if we're operating in
4506 * non-verbose non-interactive mode. (It's probably
4507 * a script, which means nobody will read the
4508 * banner _anyway_, and moreover the printing of
4509 * the banner will screw up processing on the
4510 * output of (say) plink.)
4511 */
4512 if (flags & (FLAG_VERBOSE | FLAG_INTERACTIVE)) {
51470298 4513 ssh2_pkt_getstring(ssh, &banner, &size);
32874aea 4514 if (banner)
51470298 4515 c_write_untrusted(ssh, banner, size);
32874aea 4516 }
1408a877 4517 crWaitUntilV(ispkt);
4518 }
51470298 4519 if (ssh->pktin.type == SSH2_MSG_USERAUTH_SUCCESS) {
1408a877 4520 logevent("Access granted");
51470298 4521 s->we_are_in = TRUE;
1408a877 4522 break;
4523 }
65a22376 4524
51470298 4525 if (s->kbd_inter_running &&
4526 ssh->pktin.type == SSH2_MSG_USERAUTH_INFO_REQUEST) {
b3186d64 4527 /*
45068b27 4528 * This is either a further set-of-prompts packet
4529 * in keyboard-interactive authentication, or it's
4530 * the same one and we came back here with `gotit'
4531 * set. In the former case, we must reset the
4532 * curr_prompt variable.
b3186d64 4533 */
51470298 4534 if (!s->gotit)
4535 s->curr_prompt = 0;
4536 } else if (ssh->pktin.type != SSH2_MSG_USERAUTH_FAILURE) {
6b5cf8b4 4537 bombout(("Strange packet received during authentication: type %d",
51470298 4538 ssh->pktin.type));
38c4a8da 4539 crReturnV;
65a22376 4540 }
4541
51470298 4542 s->gotit = FALSE;
65a22376 4543
1408a877 4544 /*
4545 * OK, we're now sitting on a USERAUTH_FAILURE message, so
4546 * we can look at the string in it and know what we can
4547 * helpfully try next.
4548 */
51470298 4549 if (ssh->pktin.type == SSH2_MSG_USERAUTH_FAILURE) {
1408a877 4550 char *methods;
4551 int methlen;
51470298 4552 ssh2_pkt_getstring(ssh, &methods, &methlen);
4553 s->kbd_inter_running = FALSE;
4554 if (!ssh2_pkt_getbool(ssh)) {
1408a877 4555 /*
4556 * We have received an unequivocal Access
4557 * Denied. This can translate to a variety of
4558 * messages:
4559 *
4560 * - if we'd just tried "none" authentication,
4561 * it's not worth printing anything at all
4562 *
4563 * - if we'd just tried a public key _offer_,
4564 * the message should be "Server refused our
4565 * key" (or no message at all if the key
4566 * came from Pageant)
4567 *
4568 * - if we'd just tried anything else, the
4569 * message really should be "Access denied".
4570 *
4571 * Additionally, if we'd just tried password
4572 * authentication, we should break out of this
4573 * whole loop so as to go back to the username
4574 * prompt.
4575 */
51470298 4576 if (s->type == AUTH_TYPE_NONE) {
1408a877 4577 /* do nothing */
51470298 4578 } else if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD ||
4579 s->type == AUTH_TYPE_PUBLICKEY_OFFER_QUIET) {
4580 if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD)
4581 c_write_str(ssh, "Server refused our key\r\n");
1408a877 4582 logevent("Server refused public key");
51470298 4583 } else if (s->type==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET) {
4bdf7c46 4584 /* server declined keyboard-interactive; ignore */
1408a877 4585 } else {
51470298 4586 c_write_str(ssh, "Access denied\r\n");
1408a877 4587 logevent("Access denied");
51470298 4588 if (s->type == AUTH_TYPE_PASSWORD) {
4589 s->we_are_in = FALSE;
1408a877 4590 break;
4591 }
4592 }
4593 } else {
51470298 4594 c_write_str(ssh, "Further authentication required\r\n");
1408a877 4595 logevent("Further authentication required");
4596 }
65a22376 4597
51470298 4598 s->can_pubkey =
32874aea 4599 in_commasep_string("publickey", methods, methlen);
51470298 4600 s->can_passwd =
32874aea 4601 in_commasep_string("password", methods, methlen);
86916870 4602 s->can_keyb_inter = ssh->cfg.try_ki_auth &&
761187b6 4603 in_commasep_string("keyboard-interactive", methods, methlen);
1408a877 4604 }
65a22376 4605
51470298 4606 s->method = 0;
4607 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
65a22376 4608
0405e71f 4609 /*
4610 * Most password/passphrase prompts will be
4611 * non-echoing, so we set this to 0 by default.
4612 * Exception is that some keyboard-interactive prompts
4613 * can be echoing, in which case we'll set this to 1.
4614 */
51470298 4615 s->echo = 0;
0405e71f 4616
51470298 4617 if (!s->method && s->can_pubkey &&
4618 agent_exists() && !s->tried_agent) {
1983e559 4619 /*
4620 * Attempt public-key authentication using Pageant.
4621 */
1983e559 4622 void *r;
51470298 4623 s->authed = FALSE;
1983e559 4624
51470298 4625 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4626 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
00db133f 4627
51470298 4628 s->tried_agent = TRUE;
1983e559 4629
4630 logevent("Pageant is running. Requesting keys.");
4631
4632 /* Request the keys held by the agent. */
51470298 4633 PUT_32BIT(s->request, 1);
4634 s->request[4] = SSH2_AGENTC_REQUEST_IDENTITIES;
4635 agent_query(s->request, 5, &r, &s->responselen);
4636 s->response = (unsigned char *) r;
4637 if (s->response && s->responselen >= 5 &&
4638 s->response[4] == SSH2_AGENT_IDENTITIES_ANSWER) {
4639 s->p = s->response + 5;
4640 s->nkeys = GET_32BIT(s->p);
4641 s->p += 4;
32874aea 4642 {
4643 char buf[64];
51470298 4644 sprintf(buf, "Pageant has %d SSH2 keys", s->nkeys);
32874aea 4645 logevent(buf);
4646 }
51470298 4647 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
2d466ffd 4648 void *vret;
1983e559 4649
32874aea 4650 {
4651 char buf[64];
51470298 4652 sprintf(buf, "Trying Pageant key #%d", s->keyi);
32874aea 4653 logevent(buf);
4654 }
51470298 4655 s->pklen = GET_32BIT(s->p);
4656 s->p += 4;
4657 if (s->publickey_blob &&
4658 s->pklen == s->publickey_bloblen &&
4659 !memcmp(s->p, s->publickey_blob,
4660 s->publickey_bloblen)) {
396778f1 4661 logevent("This key matches configured key file");
51470298 4662 s->tried_pubkey_config = 1;
396778f1 4663 }
d8baa528 4664 s->pkblob = (char *)s->p;
51470298 4665 s->p += s->pklen;
4666 s->alglen = GET_32BIT(s->pkblob);
4667 s->alg = s->pkblob + 4;
4668 s->commentlen = GET_32BIT(s->p);
4669 s->p += 4;
d8baa528 4670 s->commentp = (char *)s->p;
51470298 4671 s->p += s->commentlen;
4672 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4673 ssh2_pkt_addstring(ssh, s->username);
4674 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
4675 ssh2_pkt_addstring(ssh, "publickey"); /* method */
4676 ssh2_pkt_addbool(ssh, FALSE); /* no signature included */
4677 ssh2_pkt_addstring_start(ssh);
4678 ssh2_pkt_addstring_data(ssh, s->alg, s->alglen);
4679 ssh2_pkt_addstring_start(ssh);
4680 ssh2_pkt_addstring_data(ssh, s->pkblob, s->pklen);
4681 ssh2_pkt_send(ssh);
1983e559 4682
4683 crWaitUntilV(ispkt);
51470298 4684 if (ssh->pktin.type != SSH2_MSG_USERAUTH_PK_OK) {
1983e559 4685 logevent("Key refused");
4686 continue;
4687 }
4688
32874aea 4689 if (flags & FLAG_VERBOSE) {
51470298 4690 c_write_str(ssh, "Authenticating with "
4691 "public key \"");
4692 c_write(ssh, s->commentp, s->commentlen);
4693 c_write_str(ssh, "\" from agent\r\n");
32874aea 4694 }
1983e559 4695
4696 /*
4697 * Server is willing to accept the key.
4698 * Construct a SIGN_REQUEST.
4699 */
51470298 4700 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4701 ssh2_pkt_addstring(ssh, s->username);
4702 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
4703 ssh2_pkt_addstring(ssh, "publickey"); /* method */
4704 ssh2_pkt_addbool(ssh, TRUE);
4705 ssh2_pkt_addstring_start(ssh);
4706 ssh2_pkt_addstring_data(ssh, s->alg, s->alglen);
4707 ssh2_pkt_addstring_start(ssh);
4708 ssh2_pkt_addstring_data(ssh, s->pkblob, s->pklen);
4709
4710 s->siglen = ssh->pktout.length - 5 + 4 + 20;
dda87a28 4711 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
4712 s->siglen -= 4;
51470298 4713 s->len = 1; /* message type */
4714 s->len += 4 + s->pklen; /* key blob */
4715 s->len += 4 + s->siglen; /* data to sign */
4716 s->len += 4; /* flags */
3d88e64d 4717 s->agentreq = snewn(4 + s->len, char);
51470298 4718 PUT_32BIT(s->agentreq, s->len);
4719 s->q = s->agentreq + 4;
4720 *s->q++ = SSH2_AGENTC_SIGN_REQUEST;
4721 PUT_32BIT(s->q, s->pklen);
4722 s->q += 4;
4723 memcpy(s->q, s->pkblob, s->pklen);
4724 s->q += s->pklen;
4725 PUT_32BIT(s->q, s->siglen);
4726 s->q += 4;
1983e559 4727 /* Now the data to be signed... */
dda87a28 4728 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
4729 PUT_32BIT(s->q, 20);
4730 s->q += 4;
4731 }
51470298 4732 memcpy(s->q, ssh->v2_session_id, 20);
4733 s->q += 20;
4734 memcpy(s->q, ssh->pktout.data + 5,
4735 ssh->pktout.length - 5);
4736 s->q += ssh->pktout.length - 5;
1983e559 4737 /* And finally the (zero) flags word. */
51470298 4738 PUT_32BIT(s->q, 0);
4739 agent_query(s->agentreq, s->len + 4, &vret, &s->retlen);
4740 s->ret = vret;
4741 sfree(s->agentreq);
4742 if (s->ret) {
4743 if (s->ret[4] == SSH2_AGENT_SIGN_RESPONSE) {
1983e559 4744 logevent("Sending Pageant's response");
51470298 4745 ssh2_add_sigblob(ssh, s->pkblob, s->pklen,
4746 s->ret + 9,
4747 GET_32BIT(s->ret + 5));
4748 ssh2_pkt_send(ssh);
4749 s->authed = TRUE;
1983e559 4750 break;
4751 } else {
32874aea 4752 logevent
4753 ("Pageant failed to answer challenge");
51470298 4754 sfree(s->ret);
1983e559 4755 }
4756 }
4757 }
51470298 4758 if (s->authed)
1983e559 4759 continue;
4760 }
4761 }
4762
51470298 4763 if (!s->method && s->can_pubkey && s->publickey_blob
4764 && !s->tried_pubkey_config) {
1408a877 4765 unsigned char *pub_blob;
4766 char *algorithm, *comment;
4767 int pub_blob_len;
65a22376 4768
51470298 4769 s->tried_pubkey_config = TRUE;
65a22376 4770
51470298 4771 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4772 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
00db133f 4773
65a22376 4774 /*
1408a877 4775 * Try the public key supplied in the configuration.
4776 *
4777 * First, offer the public blob to see if the server is
4778 * willing to accept it.
65a22376 4779 */
d8baa528 4780 pub_blob =
9a30e26b 4781 (unsigned char *)ssh2_userkey_loadpub(&ssh->cfg.keyfile,
d8baa528 4782 &algorithm,
4783 &pub_blob_len);
1408a877 4784 if (pub_blob) {
51470298 4785 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4786 ssh2_pkt_addstring(ssh, s->username);
4787 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
4788 ssh2_pkt_addstring(ssh, "publickey"); /* method */
4789 ssh2_pkt_addbool(ssh, FALSE); /* no signature included */
4790 ssh2_pkt_addstring(ssh, algorithm);
4791 ssh2_pkt_addstring_start(ssh);
d8baa528 4792 ssh2_pkt_addstring_data(ssh, (char *)pub_blob,
4793 pub_blob_len);
51470298 4794 ssh2_pkt_send(ssh);
32874aea 4795 logevent("Offered public key"); /* FIXME */
1408a877 4796
4797 crWaitUntilV(ispkt);
51470298 4798 if (ssh->pktin.type != SSH2_MSG_USERAUTH_PK_OK) {
4799 s->gotit = TRUE;
4800 s->type = AUTH_TYPE_PUBLICKEY_OFFER_LOUD;
32874aea 4801 continue; /* key refused; give up on it */
1408a877 4802 }
65a22376 4803
1408a877 4804 logevent("Offer of public key accepted");
65a22376 4805 /*
1408a877 4806 * Actually attempt a serious authentication using
4807 * the key.
65a22376 4808 */
9a30e26b 4809 if (ssh2_userkey_encrypted(&ssh->cfg.keyfile, &comment)) {
51470298 4810 sprintf(s->pwprompt,
32874aea 4811 "Passphrase for key \"%.100s\": ",
4812 comment);
51470298 4813 s->need_pw = TRUE;
1408a877 4814 } else {
51470298 4815 s->need_pw = FALSE;
1408a877 4816 }
51470298 4817 c_write_str(ssh, "Authenticating with public key \"");
4818 c_write_str(ssh, comment);
4819 c_write_str(ssh, "\"\r\n");
4820 s->method = AUTH_PUBLICKEY_FILE;
65a22376 4821 }
1408a877 4822 }
4823
51470298 4824 if (!s->method && s->can_keyb_inter && !s->tried_keyb_inter) {
4825 s->method = AUTH_KEYBOARD_INTERACTIVE;
4826 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
4827 s->tried_keyb_inter = TRUE;
af659722 4828
51470298 4829 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4830 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
00db133f 4831
51470298 4832 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4833 ssh2_pkt_addstring(ssh, s->username);
4834 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
4835 ssh2_pkt_addstring(ssh, "keyboard-interactive"); /* method */
4836 ssh2_pkt_addstring(ssh, ""); /* lang */
4837 ssh2_pkt_addstring(ssh, "");
4838 ssh2_pkt_send(ssh);
af659722 4839
4840 crWaitUntilV(ispkt);
51470298 4841 if (ssh->pktin.type != SSH2_MSG_USERAUTH_INFO_REQUEST) {
4842 if (ssh->pktin.type == SSH2_MSG_USERAUTH_FAILURE)
4843 s->gotit = TRUE;
af659722 4844 logevent("Keyboard-interactive authentication refused");
51470298 4845 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET;
af659722 4846 continue;
4847 }
4848
51470298 4849 s->kbd_inter_running = TRUE;
4850 s->curr_prompt = 0;
af659722 4851 }
4852
51470298 4853 if (s->kbd_inter_running) {
4854 s->method = AUTH_KEYBOARD_INTERACTIVE;
4855 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
4856 s->tried_keyb_inter = TRUE;
af659722 4857
51470298 4858 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4859 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
00db133f 4860
51470298 4861 if (s->curr_prompt == 0) {
45068b27 4862 /*
4863 * We've got a fresh USERAUTH_INFO_REQUEST.
4864 * Display header data, and start going through
4865 * the prompts.
4866 */
4867 char *name, *inst, *lang;
4868 int name_len, inst_len, lang_len;
4869
51470298 4870 ssh2_pkt_getstring(ssh, &name, &name_len);
4871 ssh2_pkt_getstring(ssh, &inst, &inst_len);
4872 ssh2_pkt_getstring(ssh, &lang, &lang_len);
45068b27 4873 if (name_len > 0) {
51470298 4874 c_write_untrusted(ssh, name, name_len);
4875 c_write_str(ssh, "\r\n");
45068b27 4876 }
4877 if (inst_len > 0) {
51470298 4878 c_write_untrusted(ssh, inst, inst_len);
4879 c_write_str(ssh, "\r\n");
45068b27 4880 }
51470298 4881 s->num_prompts = ssh2_pkt_getuint32(ssh);
45068b27 4882 }
af659722 4883
45068b27 4884 /*
4885 * If there are prompts remaining in the packet,
4886 * display one and get a response.
4887 */
51470298 4888 if (s->curr_prompt < s->num_prompts) {
45068b27 4889 char *prompt;
4890 int prompt_len;
af659722 4891
51470298 4892 ssh2_pkt_getstring(ssh, &prompt, &prompt_len);
45068b27 4893 if (prompt_len > 0) {
51470298 4894 strncpy(s->pwprompt, prompt, sizeof(s->pwprompt));
4895 s->pwprompt[prompt_len < sizeof(s->pwprompt) ?
4896 prompt_len : sizeof(s->pwprompt)-1] = '\0';
45068b27 4897 } else {
51470298 4898 strcpy(s->pwprompt,
45068b27 4899 "<server failed to send prompt>: ");
4900 }
51470298 4901 s->echo = ssh2_pkt_getbool(ssh);
4902 s->need_pw = TRUE;
45068b27 4903 } else
51470298 4904 s->need_pw = FALSE;
af659722 4905 }
4906
51470298 4907 if (!s->method && s->can_passwd) {
4908 s->method = AUTH_PASSWORD;
4909 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4910 ssh->pkt_ctx |= SSH2_PKTCTX_PASSWORD;
4911 sprintf(s->pwprompt, "%.90s@%.90s's password: ", s->username,
4912 ssh->savedhost);
4913 s->need_pw = TRUE;
1408a877 4914 }
4915
51470298 4916 if (s->need_pw) {
fa17a66e 4917 if (ssh_get_line) {
51470298 4918 if (!ssh_get_line(s->pwprompt, s->password,
4919 sizeof(s->password), TRUE)) {
1408a877 4920 /*
fa17a66e 4921 * get_line failed to get a password (for
4922 * example because one was supplied on the
4923 * command line which has already failed to
4924 * work). Terminate.
1408a877 4925 */
51470298 4926 ssh2_pkt_init(ssh, SSH2_MSG_DISCONNECT);
4927 ssh2_pkt_adduint32(ssh,SSH2_DISCONNECT_BY_APPLICATION);
4928 ssh2_pkt_addstring(ssh, "No more passwords available"
4929 " to try");
4930 ssh2_pkt_addstring(ssh, "en"); /* language tag */
4931 ssh2_pkt_send(ssh);
247308b5 4932 logevent("Unable to authenticate");
a8327734 4933 connection_fatal(ssh->frontend,
4934 "Unable to authenticate");
3bb2f322 4935 ssh_closing((Plug)ssh, NULL, 0, 0);
1408a877 4936 crReturnV;
4937 }
4938 } else {
51470298 4939 int ret; /* need not be saved across crReturn */
4940 c_write_untrusted(ssh, s->pwprompt, strlen(s->pwprompt));
4941 ssh->send_ok = 1;
1408a877 4942
51470298 4943 setup_userpass_input(ssh, s->password,
4944 sizeof(s->password), s->echo);
0405e71f 4945 do {
1408a877 4946 crWaitUntilV(!ispkt);
51470298 4947 ret = process_userpass_input(ssh, in, inlen);
0405e71f 4948 } while (ret == 0);
4949 if (ret < 0)
4950 cleanup_exit(0);
51470298 4951 c_write_str(ssh, "\r\n");
65a22376 4952 }
65a22376 4953 }
65a22376 4954
51470298 4955 if (s->method == AUTH_PUBLICKEY_FILE) {
1408a877 4956 /*
4957 * We have our passphrase. Now try the actual authentication.
4958 */
4959 struct ssh2_userkey *key;
65a22376 4960
9a30e26b 4961 key = ssh2_load_userkey(&ssh->cfg.keyfile, s->password);
1408a877 4962 if (key == SSH2_WRONG_PASSPHRASE || key == NULL) {
4963 if (key == SSH2_WRONG_PASSPHRASE) {
51470298 4964 c_write_str(ssh, "Wrong passphrase\r\n");
4965 s->tried_pubkey_config = FALSE;
1408a877 4966 } else {
51470298 4967 c_write_str(ssh, "Unable to load private key\r\n");
4968 s->tried_pubkey_config = TRUE;
1408a877 4969 }
4970 /* Send a spurious AUTH_NONE to return to the top. */
51470298 4971 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4972 ssh2_pkt_addstring(ssh, s->username);
4973 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
4974 ssh2_pkt_addstring(ssh, "none"); /* method */
4975 ssh2_pkt_send(ssh);
4976 s->type = AUTH_TYPE_NONE;
1408a877 4977 } else {
1dd353b5 4978 unsigned char *pkblob, *sigblob, *sigdata;
4979 int pkblob_len, sigblob_len, sigdata_len;
dda87a28 4980 int p;
65a22376 4981
1408a877 4982 /*
4983 * We have loaded the private key and the server
4984 * has announced that it's willing to accept it.
4985 * Hallelujah. Generate a signature and send it.
4986 */
51470298 4987 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4988 ssh2_pkt_addstring(ssh, s->username);
4989 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
4990 ssh2_pkt_addstring(ssh, "publickey"); /* method */
4991 ssh2_pkt_addbool(ssh, TRUE);
4992 ssh2_pkt_addstring(ssh, key->alg->name);
1dd353b5 4993 pkblob = key->alg->public_blob(key->data, &pkblob_len);
51470298 4994 ssh2_pkt_addstring_start(ssh);
d8baa528 4995 ssh2_pkt_addstring_data(ssh, (char *)pkblob, pkblob_len);
1408a877 4996
4997 /*
4998 * The data to be signed is:
4999 *
5000 * string session-id
5001 *
5002 * followed by everything so far placed in the
5003 * outgoing packet.
5004 */
51470298 5005 sigdata_len = ssh->pktout.length - 5 + 4 + 20;
dda87a28 5006 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
5007 sigdata_len -= 4;
92d60585 5008 sigdata = snewn(sigdata_len, unsigned char);
dda87a28 5009 p = 0;
5010 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
5011 PUT_32BIT(sigdata+p, 20);
5012 p += 4;
5013 }
5014 memcpy(sigdata+p, ssh->v2_session_id, 20); p += 20;
5015 memcpy(sigdata+p, ssh->pktout.data + 5,
51470298 5016 ssh->pktout.length - 5);
dda87a28 5017 p += ssh->pktout.length - 5;
5018 assert(p == sigdata_len);
d8baa528 5019 sigblob = key->alg->sign(key->data, (char *)sigdata,
1dd353b5 5020 sigdata_len, &sigblob_len);
51470298 5021 ssh2_add_sigblob(ssh, pkblob, pkblob_len,
1dd353b5 5022 sigblob, sigblob_len);
5023 sfree(pkblob);
5024 sfree(sigblob);
1408a877 5025 sfree(sigdata);
5026
51470298 5027 ssh2_pkt_send(ssh);
5028 s->type = AUTH_TYPE_PUBLICKEY;
1408a877 5029 }
51470298 5030 } else if (s->method == AUTH_PASSWORD) {
65a22376 5031 /*
1408a877 5032 * We send the password packet lumped tightly together with
5033 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
5034 * string long enough to make the total length of the two
5035 * packets constant. This should ensure that a passive
5036 * listener doing traffic analyis can't work out the length
5037 * of the password.
5038 *
5039 * For this to work, we need an assumption about the
5040 * maximum length of the password packet. I think 256 is
5041 * pretty conservative. Anyone using a password longer than
5042 * that probably doesn't have much to worry about from
5043 * people who find out how long their password is!
65a22376 5044 */
51470298 5045 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
5046 ssh2_pkt_addstring(ssh, s->username);
5047 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
5048 ssh2_pkt_addstring(ssh, "password");
5049 ssh2_pkt_addbool(ssh, FALSE);
5050 ssh2_pkt_addstring(ssh, s->password);
1409c1b3 5051 memset(s->password, 0, sizeof(s->password));
51470298 5052 ssh2_pkt_defer(ssh);
65a22376 5053 /*
1408a877 5054 * We'll include a string that's an exact multiple of the
5055 * cipher block size. If the cipher is NULL for some
5056 * reason, we don't do this trick at all because we gain
5057 * nothing by it.
65a22376 5058 */
51470298 5059 if (ssh->cscipher) {
32874aea 5060 int stringlen, i;
5061
51470298 5062 stringlen = (256 - ssh->deferred_len);
5063 stringlen += ssh->cscipher->blksize - 1;
5064 stringlen -= (stringlen % ssh->cscipher->blksize);
5065 if (ssh->cscomp) {
32874aea 5066 /*
5067 * Temporarily disable actual compression,
5068 * so we can guarantee to get this string
5069 * exactly the length we want it. The
5070 * compression-disabling routine should
5071 * return an integer indicating how many
5072 * bytes we should adjust our string length
5073 * by.
5074 */
5366aed8 5075 stringlen -=
5076 ssh->cscomp->disable_compression(ssh->cs_comp_ctx);
32874aea 5077 }
51470298 5078 ssh2_pkt_init(ssh, SSH2_MSG_IGNORE);
5079 ssh2_pkt_addstring_start(ssh);
6e9e9520 5080 for (i = 0; i < stringlen; i++) {
32874aea 5081 char c = (char) random_byte();
51470298 5082 ssh2_pkt_addstring_data(ssh, &c, 1);
65a22376 5083 }
51470298 5084 ssh2_pkt_defer(ssh);
65a22376 5085 }
51470298 5086 ssh_pkt_defersend(ssh);
0d43337a 5087 logevent("Sent password");
51470298 5088 s->type = AUTH_TYPE_PASSWORD;
5089 } else if (s->method == AUTH_KEYBOARD_INTERACTIVE) {
5090 if (s->curr_prompt == 0) {
5091 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_INFO_RESPONSE);
5092 ssh2_pkt_adduint32(ssh, s->num_prompts);
45068b27 5093 }
51470298 5094 if (s->need_pw) { /* only add pw if we just got one! */
5095 ssh2_pkt_addstring(ssh, s->password);
5096 memset(s->password, 0, sizeof(s->password));
5097 s->curr_prompt++;
45068b27 5098 }
51470298 5099 if (s->curr_prompt >= s->num_prompts) {
5100 ssh2_pkt_send(ssh);
45068b27 5101 } else {
5102 /*
5103 * If there are prompts remaining, we set
5104 * `gotit' so that we won't attempt to get
5105 * another packet. Then we go back round the
5106 * loop and will end up retrieving another
5107 * prompt out of the existing packet. Funky or
5108 * what?
5109 */
51470298 5110 s->gotit = TRUE;
45068b27 5111 }
51470298 5112 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
1408a877 5113 } else {
51470298 5114 c_write_str(ssh, "No supported authentication methods"
5115 " left to try!\r\n");
5116 logevent("No supported authentications offered."
5117 " Disconnecting");
5118 ssh2_pkt_init(ssh, SSH2_MSG_DISCONNECT);
5119 ssh2_pkt_adduint32(ssh, SSH2_DISCONNECT_BY_APPLICATION);
5120 ssh2_pkt_addstring(ssh, "No supported authentication"
5121 " methods available");
5122 ssh2_pkt_addstring(ssh, "en"); /* language tag */
5123 ssh2_pkt_send(ssh);
3bb2f322 5124 ssh_closing((Plug)ssh, NULL, 0, 0);
1408a877 5125 crReturnV;
65a22376 5126 }
65a22376 5127 }
51470298 5128 } while (!s->we_are_in);
7cca0d81 5129
5130 /*
5131 * Now we're authenticated for the connection protocol. The
5132 * connection protocol will automatically have started at this
5133 * point; there's no need to send SERVICE_REQUEST.
5134 */
5135
5136 /*
5137 * So now create a channel with a session in it.
5138 */
51470298 5139 ssh->channels = newtree234(ssh_channelcmp);
3d88e64d 5140 ssh->mainchan = snew(struct ssh_channel);
51470298 5141 ssh->mainchan->ssh = ssh;
5142 ssh->mainchan->localid = alloc_channel_id(ssh);
5143 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_OPEN);
5144 ssh2_pkt_addstring(ssh, "session");
5145 ssh2_pkt_adduint32(ssh, ssh->mainchan->localid);
5146 ssh->mainchan->v.v2.locwindow = OUR_V2_WINSIZE;
5147 ssh2_pkt_adduint32(ssh, ssh->mainchan->v.v2.locwindow);/* our window size */
5148 ssh2_pkt_adduint32(ssh, 0x4000UL); /* our max pkt size */
5149 ssh2_pkt_send(ssh);
7cca0d81 5150 crWaitUntilV(ispkt);
51470298 5151 if (ssh->pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
6b5cf8b4 5152 bombout(("Server refused to open a session"));
32874aea 5153 crReturnV;
5154 /* FIXME: error data comes back in FAILURE packet */
7cca0d81 5155 }
51470298 5156 if (ssh2_pkt_getuint32(ssh) != ssh->mainchan->localid) {
6b5cf8b4 5157 bombout(("Server's channel confirmation cited wrong channel"));
32874aea 5158 crReturnV;
7cca0d81 5159 }
51470298 5160 ssh->mainchan->remoteid = ssh2_pkt_getuint32(ssh);
5161 ssh->mainchan->type = CHAN_MAINSESSION;
5162 ssh->mainchan->closes = 0;
5163 ssh->mainchan->v.v2.remwindow = ssh2_pkt_getuint32(ssh);
5164 ssh->mainchan->v.v2.remmaxpkt = ssh2_pkt_getuint32(ssh);
5165 bufchain_init(&ssh->mainchan->v.v2.outbuffer);
5166 add234(ssh->channels, ssh->mainchan);
7cca0d81 5167 logevent("Opened channel for session");
5168
5169 /*
783415f8 5170 * Potentially enable X11 forwarding.
5171 */
86916870 5172 if (ssh->cfg.x11_forward) {
32874aea 5173 char proto[20], data[64];
5174 logevent("Requesting X11 forwarding");
302121de 5175 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
86916870 5176 data, sizeof(data), ssh->cfg.x11_auth);
5177 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
51470298 5178 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
5179 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
5180 ssh2_pkt_addstring(ssh, "x11-req");
5181 ssh2_pkt_addbool(ssh, 1); /* want reply */
5182 ssh2_pkt_addbool(ssh, 0); /* many connections */
5183 ssh2_pkt_addstring(ssh, proto);
5184 ssh2_pkt_addstring(ssh, data);
86916870 5185 ssh2_pkt_adduint32(ssh, x11_get_screen_number(ssh->cfg.x11_display));
51470298 5186 ssh2_pkt_send(ssh);
32874aea 5187
5188 do {
5189 crWaitUntilV(ispkt);
51470298 5190 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
5191 unsigned i = ssh2_pkt_getuint32(ssh);
32874aea 5192 struct ssh_channel *c;
51470298 5193 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5194 if (!c)
5195 continue; /* nonexistent channel */
51470298 5196 c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
32874aea 5197 }
51470298 5198 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
32874aea 5199
51470298 5200 if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
5201 if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 5202 bombout(("Unexpected response to X11 forwarding request:"
51470298 5203 " packet type %d", ssh->pktin.type));
32874aea 5204 crReturnV;
5205 }
5206 logevent("X11 forwarding refused");
5207 } else {
5208 logevent("X11 forwarding enabled");
51470298 5209 ssh->X11_fwd_enabled = TRUE;
32874aea 5210 }
783415f8 5211 }
5212
5213 /*
bc240b21 5214 * Enable port forwardings.
5215 */
5216 {
bc240b21 5217 char type;
5218 int n;
a4fc0d74 5219 int sport,dport,sserv,dserv;
6ee9b735 5220 char sports[256], dports[256], saddr[256], host[256];
bc240b21 5221
51470298 5222 ssh->rportfwds = newtree234(ssh_rportcmp_ssh2);
bc240b21 5223 /* Add port forwardings. */
86916870 5224 ssh->portfwd_strptr = ssh->cfg.portfwd;
51470298 5225 while (*ssh->portfwd_strptr) {
5226 type = *ssh->portfwd_strptr++;
6ee9b735 5227 saddr[0] = '\0';
bc240b21 5228 n = 0;
6ee9b735 5229 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != '\t') {
5230 if (*ssh->portfwd_strptr == ':') {
5231 /*
5232 * We've seen a colon in the middle of the
5233 * source port number. This means that
5234 * everything we've seen until now is the
5235 * source _address_, so we'll move it into
5236 * saddr and start sports from the beginning
5237 * again.
5238 */
5239 ssh->portfwd_strptr++;
5240 sports[n] = '\0';
5241 strcpy(saddr, sports);
5242 n = 0;
5243 }
5244 if (n < 255) sports[n++] = *ssh->portfwd_strptr++;
5245 }
bc240b21 5246 sports[n] = 0;
820ebe3b 5247 if (type != 'D') {
5248 if (*ssh->portfwd_strptr == '\t')
5249 ssh->portfwd_strptr++;
5250 n = 0;
5251 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != ':') {
5252 if (n < 255) host[n++] = *ssh->portfwd_strptr++;
5253 }
5254 host[n] = 0;
5255 if (*ssh->portfwd_strptr == ':')
5256 ssh->portfwd_strptr++;
5257 n = 0;
5258 while (*ssh->portfwd_strptr) {
5259 if (n < 255) dports[n++] = *ssh->portfwd_strptr++;
5260 }
5261 dports[n] = 0;
51470298 5262 ssh->portfwd_strptr++;
820ebe3b 5263 dport = atoi(dports);
5264 dserv = 0;
5265 if (dport == 0) {
5266 dserv = 1;
5267 dport = net_service_lookup(dports);
5268 if (!dport) {
5269 logeventf(ssh, "Service lookup failed for destination"
5270 " port \"%s\"", dports);
5271 }
a4fc0d74 5272 }
820ebe3b 5273 } else {
5274 while (*ssh->portfwd_strptr) ssh->portfwd_strptr++;
52893a36 5275 dport = -1;
a4fc0d74 5276 }
bc240b21 5277 sport = atoi(sports);
a4fc0d74 5278 sserv = 0;
5279 if (sport == 0) {
5280 sserv = 1;
68a49acb 5281 sport = net_service_lookup(sports);
5282 if (!sport) {
57356d63 5283 logeventf(ssh, "Service lookup failed for source"
5284 " port \"%s\"", sports);
a4fc0d74 5285 }
5286 }
bc240b21 5287 if (sport && dport) {
5288 if (type == 'L') {
6ee9b735 5289 pfd_addforward(host, dport, *saddr ? saddr : NULL,
e8fa8f62 5290 sport, ssh, &ssh->cfg);
6ee9b735 5291 logeventf(ssh, "Local port %.*s%.*s%.*s%.*s%d%.*s"
5292 " forwarding to %s:%.*s%.*s%d%.*s",
5293 (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
5294 (int)(*saddr?1:0), ":",
57356d63 5295 (int)(sserv ? strlen(sports) : 0), sports,
5296 sserv, "(", sport, sserv, ")",
5297 host,
5298 (int)(dserv ? strlen(dports) : 0), dports,
5299 dserv, "(", dport, dserv, ")");
820ebe3b 5300 } else if (type == 'D') {
5301 pfd_addforward(NULL, -1, *saddr ? saddr : NULL,
5302 sport, ssh, &ssh->cfg);
5303 logeventf(ssh, "Local port %.*s%.*s%.*s%.*s%d%.*s"
5304 " doing SOCKS dynamic forwarding",
5305 (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
5306 (int)(*saddr?1:0), ":",
5307 (int)(sserv ? strlen(sports) : 0), sports,
5308 sserv, "(", sport, sserv, ")");
bc240b21 5309 } else {
5310 struct ssh_rportfwd *pf;
3d88e64d 5311 pf = snew(struct ssh_rportfwd);
bc240b21 5312 strcpy(pf->dhost, host);
5313 pf->dport = dport;
5314 pf->sport = sport;
51470298 5315 if (add234(ssh->rportfwds, pf) != pf) {
57356d63 5316 logeventf(ssh, "Duplicate remote port forwarding"
5317 " to %s:%d", host, dport);
bc240b21 5318 sfree(pf);
5319 } else {
6ee9b735 5320 logeventf(ssh, "Requesting remote port "
5321 "%.*s%.*s%.*s%.*s%d%.*s"
57356d63 5322 " forward to %s:%.*s%.*s%d%.*s",
6ee9b735 5323 (int)(*saddr?strlen(saddr):0),
5324 *saddr?saddr:NULL,
5325 (int)(*saddr?1:0), ":",
57356d63 5326 (int)(sserv ? strlen(sports) : 0), sports,
5327 sserv, "(", sport, sserv, ")",
5328 host,
5329 (int)(dserv ? strlen(dports) : 0), dports,
5330 dserv, "(", dport, dserv, ")");
51470298 5331 ssh2_pkt_init(ssh, SSH2_MSG_GLOBAL_REQUEST);
5332 ssh2_pkt_addstring(ssh, "tcpip-forward");
5333 ssh2_pkt_addbool(ssh, 1);/* want reply */
6ee9b735 5334 if (*saddr)
5335 ssh2_pkt_addstring(ssh, saddr);
86916870 5336 if (ssh->cfg.rport_acceptall)
51470298 5337 ssh2_pkt_addstring(ssh, "0.0.0.0");
beefa433 5338 else
51470298 5339 ssh2_pkt_addstring(ssh, "127.0.0.1");
5340 ssh2_pkt_adduint32(ssh, sport);
5341 ssh2_pkt_send(ssh);
bc240b21 5342
5343 do {
5344 crWaitUntilV(ispkt);
51470298 5345 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
5346 unsigned i = ssh2_pkt_getuint32(ssh);
bc240b21 5347 struct ssh_channel *c;
51470298 5348 c = find234(ssh->channels, &i, ssh_channelfind);
bc240b21 5349 if (!c)
5350 continue;/* nonexistent channel */
51470298 5351 c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
bc240b21 5352 }
51470298 5353 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
bc240b21 5354
51470298 5355 if (ssh->pktin.type != SSH2_MSG_REQUEST_SUCCESS) {
5356 if (ssh->pktin.type != SSH2_MSG_REQUEST_FAILURE) {
6b5cf8b4 5357 bombout(("Unexpected response to port "
c9886e66 5358 "forwarding request: packet type %d",
51470298 5359 ssh->pktin.type));
bc240b21 5360 crReturnV;
5361 }
5362 logevent("Server refused this port forwarding");
5363 } else {
5364 logevent("Remote port forwarding enabled");
5365 }
5366 }
5367 }
5368 }
5369 }
5370 }
5371
5372 /*
36c2a3e9 5373 * Potentially enable agent forwarding.
5374 */
86916870 5375 if (ssh->cfg.agentfwd && agent_exists()) {
32874aea 5376 logevent("Requesting OpenSSH-style agent forwarding");
51470298 5377 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
5378 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
5379 ssh2_pkt_addstring(ssh, "auth-agent-req@openssh.com");
5380 ssh2_pkt_addbool(ssh, 1); /* want reply */
5381 ssh2_pkt_send(ssh);
32874aea 5382
5383 do {
5384 crWaitUntilV(ispkt);
51470298 5385 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
5386 unsigned i = ssh2_pkt_getuint32(ssh);
32874aea 5387 struct ssh_channel *c;
51470298 5388 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5389 if (!c)
5390 continue; /* nonexistent channel */
51470298 5391 c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
32874aea 5392 }
51470298 5393 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
32874aea 5394
51470298 5395 if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
5396 if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 5397 bombout(("Unexpected response to agent forwarding request:"
51470298 5398 " packet type %d", ssh->pktin.type));
32874aea 5399 crReturnV;
5400 }
5401 logevent("Agent forwarding refused");
5402 } else {
5403 logevent("Agent forwarding enabled");
51470298 5404 ssh->agentfwd_enabled = TRUE;
32874aea 5405 }
36c2a3e9 5406 }
5407
5408 /*
7cca0d81 5409 * Now allocate a pty for the session.
5410 */
86916870 5411 if (!ssh->cfg.nopty) {
51470298 5412 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
5413 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid); /* recipient channel */
5414 ssh2_pkt_addstring(ssh, "pty-req");
5415 ssh2_pkt_addbool(ssh, 1); /* want reply */
86916870 5416 ssh2_pkt_addstring(ssh, ssh->cfg.termtype);
51470298 5417 ssh2_pkt_adduint32(ssh, ssh->term_width);
5418 ssh2_pkt_adduint32(ssh, ssh->term_height);
5419 ssh2_pkt_adduint32(ssh, 0); /* pixel width */
5420 ssh2_pkt_adduint32(ssh, 0); /* pixel height */
5421 ssh2_pkt_addstring_start(ssh);
5422 ssh2_pkt_addstring_data(ssh, "\0", 1); /* TTY_OP_END, no special options */
5423 ssh2_pkt_send(ssh);
5424 ssh->state = SSH_STATE_INTERMED;
32874aea 5425
5426 do {
5427 crWaitUntilV(ispkt);
51470298 5428 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
5429 unsigned i = ssh2_pkt_getuint32(ssh);
32874aea 5430 struct ssh_channel *c;
51470298 5431 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5432 if (!c)
5433 continue; /* nonexistent channel */
51470298 5434 c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
32874aea 5435 }
51470298 5436 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
32874aea 5437
51470298 5438 if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
5439 if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 5440 bombout(("Unexpected response to pty request:"
51470298 5441 " packet type %d", ssh->pktin.type));
32874aea 5442 crReturnV;
5443 }
51470298 5444 c_write_str(ssh, "Server refused to allocate pty\r\n");
5445 ssh->editing = ssh->echoing = 1;
32874aea 5446 } else {
5447 logevent("Allocated pty");
5448 }
0965bee0 5449 } else {
51470298 5450 ssh->editing = ssh->echoing = 1;
7cca0d81 5451 }
5452
5453 /*
fd5e5847 5454 * Start a shell or a remote command. We may have to attempt
5455 * this twice if the config data has provided a second choice
5456 * of command.
7cca0d81 5457 */
fd5e5847 5458 while (1) {
5459 int subsys;
5460 char *cmd;
5461
51470298 5462 if (ssh->fallback_cmd) {
86916870 5463 subsys = ssh->cfg.ssh_subsys2;
5464 cmd = ssh->cfg.remote_cmd_ptr2;
fd5e5847 5465 } else {
86916870 5466 subsys = ssh->cfg.ssh_subsys;
5467 cmd = ssh->cfg.remote_cmd_ptr;
fd5e5847 5468 }
5469
51470298 5470 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
5471 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid); /* recipient channel */
fd5e5847 5472 if (subsys) {
51470298 5473 ssh2_pkt_addstring(ssh, "subsystem");
5474 ssh2_pkt_addbool(ssh, 1); /* want reply */
5475 ssh2_pkt_addstring(ssh, cmd);
fd5e5847 5476 } else if (*cmd) {
51470298 5477 ssh2_pkt_addstring(ssh, "exec");
5478 ssh2_pkt_addbool(ssh, 1); /* want reply */
5479 ssh2_pkt_addstring(ssh, cmd);
fd5e5847 5480 } else {
51470298 5481 ssh2_pkt_addstring(ssh, "shell");
5482 ssh2_pkt_addbool(ssh, 1); /* want reply */
32874aea 5483 }
51470298 5484 ssh2_pkt_send(ssh);
fd5e5847 5485 do {
5486 crWaitUntilV(ispkt);
51470298 5487 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
5488 unsigned i = ssh2_pkt_getuint32(ssh);
fd5e5847 5489 struct ssh_channel *c;
51470298 5490 c = find234(ssh->channels, &i, ssh_channelfind);
fd5e5847 5491 if (!c)
5492 continue; /* nonexistent channel */
51470298 5493 c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
fd5e5847 5494 }
51470298 5495 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
5496 if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
5497 if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 5498 bombout(("Unexpected response to shell/command request:"
51470298 5499 " packet type %d", ssh->pktin.type));
fd5e5847 5500 crReturnV;
5501 }
5502 /*
5503 * We failed to start the command. If this is the
5504 * fallback command, we really are finished; if it's
5505 * not, and if the fallback command exists, try falling
5506 * back to it before complaining.
5507 */
86916870 5508 if (!ssh->fallback_cmd && ssh->cfg.remote_cmd_ptr2 != NULL) {
fd5e5847 5509 logevent("Primary command failed; attempting fallback");
51470298 5510 ssh->fallback_cmd = TRUE;
fd5e5847 5511 continue;
5512 }
6b5cf8b4 5513 bombout(("Server refused to start a shell/command"));
32874aea 5514 crReturnV;
fd5e5847 5515 } else {
5516 logevent("Started a shell/command");
32874aea 5517 }
fd5e5847 5518 break;
7cca0d81 5519 }
5520
51470298 5521 ssh->state = SSH_STATE_SESSION;
5522 if (ssh->size_needed)
5523 ssh_size(ssh, ssh->term_width, ssh->term_height);
5524 if (ssh->eof_needed)
5525 ssh_special(ssh, TS_EOF);
6e48c3fe 5526
7cca0d81 5527 /*
5528 * Transfer data!
5529 */
b9d7bcad 5530 if (ssh->ldisc)
5531 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
51470298 5532 ssh->send_ok = 1;
7cca0d81 5533 while (1) {
e5574168 5534 crReturnV;
51470298 5535 s->try_send = FALSE;
7cca0d81 5536 if (ispkt) {
51470298 5537 if (ssh->pktin.type == SSH2_MSG_CHANNEL_DATA ||
5538 ssh->pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
32874aea 5539 char *data;
5540 int length;
51470298 5541 unsigned i = ssh2_pkt_getuint32(ssh);
32874aea 5542 struct ssh_channel *c;
51470298 5543 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5544 if (!c)
5545 continue; /* nonexistent channel */
51470298 5546 if (ssh->pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
5547 ssh2_pkt_getuint32(ssh) != SSH2_EXTENDED_DATA_STDERR)
32874aea 5548 continue; /* extended but not stderr */
51470298 5549 ssh2_pkt_getstring(ssh, &data, &length);
32874aea 5550 if (data) {
5471d09a 5551 int bufsize;
5552 c->v.v2.locwindow -= length;
32874aea 5553 switch (c->type) {
5554 case CHAN_MAINSESSION:
5471d09a 5555 bufsize =
51470298 5556 from_backend(ssh->frontend, ssh->pktin.type ==
5471d09a 5557 SSH2_MSG_CHANNEL_EXTENDED_DATA,
5558 data, length);
32874aea 5559 break;
5560 case CHAN_X11:
5471d09a 5561 bufsize = x11_send(c->u.x11.s, data, length);
32874aea 5562 break;
d74d141c 5563 case CHAN_SOCKDATA:
5471d09a 5564 bufsize = pfd_send(c->u.pfd.s, data, length);
bc240b21 5565 break;
36c2a3e9 5566 case CHAN_AGENT:
32874aea 5567 while (length > 0) {
5568 if (c->u.a.lensofar < 4) {
5569 int l = min(4 - c->u.a.lensofar, length);
5570 memcpy(c->u.a.msglen + c->u.a.lensofar,
5571 data, l);
5572 data += l;
5573 length -= l;
5574 c->u.a.lensofar += l;
5575 }
5576 if (c->u.a.lensofar == 4) {
5577 c->u.a.totallen =
5578 4 + GET_32BIT(c->u.a.msglen);
3d88e64d 5579 c->u.a.message = snewn(c->u.a.totallen,
5580 unsigned char);
32874aea 5581 memcpy(c->u.a.message, c->u.a.msglen, 4);
5582 }
5583 if (c->u.a.lensofar >= 4 && length > 0) {
5584 int l =
5585 min(c->u.a.totallen - c->u.a.lensofar,
5586 length);
5587 memcpy(c->u.a.message + c->u.a.lensofar,
5588 data, l);
5589 data += l;
5590 length -= l;
5591 c->u.a.lensofar += l;
5592 }
5593 if (c->u.a.lensofar == c->u.a.totallen) {
5594 void *reply, *sentreply;
5595 int replylen;
5596 agent_query(c->u.a.message,
5597 c->u.a.totallen, &reply,
5598 &replylen);
5599 if (reply)
5600 sentreply = reply;
5601 else {
5602 /* Fake SSH_AGENT_FAILURE. */
5603 sentreply = "\0\0\0\1\5";
5604 replylen = 5;
5605 }
51470298 5606 ssh2_add_channel_data(c, sentreply, replylen);
5607 s->try_send = TRUE;
32874aea 5608 if (reply)
5609 sfree(reply);
5610 sfree(c->u.a.message);
5611 c->u.a.lensofar = 0;
5612 }
5613 }
5471d09a 5614 bufsize = 0;
32874aea 5615 break;
5616 }
5617 /*
5471d09a 5618 * If we are not buffering too much data,
5619 * enlarge the window again at the remote side.
32874aea 5620 */
5471d09a 5621 if (bufsize < OUR_V2_WINSIZE)
5622 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
32874aea 5623 }
51470298 5624 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_EOF) {
5625 unsigned i = ssh2_pkt_getuint32(ssh);
32874aea 5626 struct ssh_channel *c;
5627
51470298 5628 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5629 if (!c)
5630 continue; /* nonexistent channel */
5631
5632 if (c->type == CHAN_X11) {
5633 /*
5634 * Remote EOF on an X11 channel means we should
5635 * wrap up and close the channel ourselves.
5636 */
5637 x11_close(c->u.x11.s);
5638 sshfwd_close(c);
5639 } else if (c->type == CHAN_AGENT) {
36c2a3e9 5640 sshfwd_close(c);
d74d141c 5641 } else if (c->type == CHAN_SOCKDATA) {
bc240b21 5642 pfd_close(c->u.pfd.s);
5643 sshfwd_close(c);
36c2a3e9 5644 }
51470298 5645 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_CLOSE) {
5646 unsigned i = ssh2_pkt_getuint32(ssh);
32874aea 5647 struct ssh_channel *c;
5648
51470298 5649 c = find234(ssh->channels, &i, ssh_channelfind);
d0d844c1 5650 if (!c || ((int)c->remoteid) == -1) {
6b5cf8b4 5651 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
d0d844c1 5652 c ? "half-open" : "nonexistent", i));
5653 }
32874aea 5654 /* Do pre-close processing on the channel. */
5655 switch (c->type) {
5656 case CHAN_MAINSESSION:
5657 break; /* nothing to see here, move along */
5658 case CHAN_X11:
92f157bd 5659 if (c->u.x11.s != NULL)
5660 x11_close(c->u.x11.s);
5661 sshfwd_close(c);
32874aea 5662 break;
5663 case CHAN_AGENT:
92f157bd 5664 sshfwd_close(c);
32874aea 5665 break;
d74d141c 5666 case CHAN_SOCKDATA:
92f157bd 5667 if (c->u.pfd.s != NULL)
5668 pfd_close(c->u.pfd.s);
5669 sshfwd_close(c);
bc240b21 5670 break;
32874aea 5671 }
92f157bd 5672 if (c->closes == 0) {
51470298 5673 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_CLOSE);
5674 ssh2_pkt_adduint32(ssh, c->remoteid);
5675 ssh2_pkt_send(ssh);
92f157bd 5676 }
51470298 5677 del234(ssh->channels, c);
5471d09a 5678 bufchain_clear(&c->v.v2.outbuffer);
32874aea 5679 sfree(c);
5680
5681 /*
5682 * See if that was the last channel left open.
5683 */
51470298 5684 if (count234(ssh->channels) == 0) {
3bb2f322 5685 logevent("All channels closed. Disconnecting");
ca2914d1 5686#if 0
5687 /*
5688 * We used to send SSH_MSG_DISCONNECT here,
5689 * because I'd believed that _every_ conforming
5690 * SSH2 connection had to end with a disconnect
5691 * being sent by at least one side; apparently
5692 * I was wrong and it's perfectly OK to
5693 * unceremoniously slam the connection shut
5694 * when you're done, and indeed OpenSSH feels
5695 * this is more polite than sending a
5696 * DISCONNECT. So now we don't.
5697 */
51470298 5698 ssh2_pkt_init(ssh, SSH2_MSG_DISCONNECT);
5699 ssh2_pkt_adduint32(ssh, SSH2_DISCONNECT_BY_APPLICATION);
5700 ssh2_pkt_addstring(ssh, "All open channels closed");
5701 ssh2_pkt_addstring(ssh, "en"); /* language tag */
5702 ssh2_pkt_send(ssh);
ca2914d1 5703#endif
3bb2f322 5704 ssh_closing((Plug)ssh, NULL, 0, 0);
32874aea 5705 crReturnV;
5706 }
5707 continue; /* remote sends close; ignore (FIXME) */
51470298 5708 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
5709 unsigned i = ssh2_pkt_getuint32(ssh);
32874aea 5710 struct ssh_channel *c;
51470298 5711 c = find234(ssh->channels, &i, ssh_channelfind);
a6253970 5712 if (!c || c->closes)
5713 continue; /* nonexistent or closing channel */
51470298 5714 c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
5715 s->try_send = TRUE;
5716 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
5717 unsigned i = ssh2_pkt_getuint32(ssh);
bc240b21 5718 struct ssh_channel *c;
51470298 5719 c = find234(ssh->channels, &i, ssh_channelfind);
bc240b21 5720 if (!c)
5721 continue; /* nonexistent channel */
5722 if (c->type != CHAN_SOCKDATA_DORMANT)
5723 continue; /* dunno why they're confirming this */
51470298 5724 c->remoteid = ssh2_pkt_getuint32(ssh);
bc240b21 5725 c->type = CHAN_SOCKDATA;
51470298 5726 c->v.v2.remwindow = ssh2_pkt_getuint32(ssh);
5727 c->v.v2.remmaxpkt = ssh2_pkt_getuint32(ssh);
4ed34d25 5728 if (c->u.pfd.s)
5729 pfd_confirm(c->u.pfd.s);
5730 if (c->closes) {
5731 /*
5732 * We have a pending close on this channel,
5733 * which we decided on before the server acked
5734 * the channel open. So now we know the
5735 * remoteid, we can close it again.
5736 */
51470298 5737 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_CLOSE);
5738 ssh2_pkt_adduint32(ssh, c->remoteid);
5739 ssh2_pkt_send(ssh);
4ed34d25 5740 }
51470298 5741 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_OPEN_FAILURE) {
5742 unsigned i = ssh2_pkt_getuint32(ssh);
724cface 5743 struct ssh_channel *c;
51470298 5744 c = find234(ssh->channels, &i, ssh_channelfind);
724cface 5745 if (!c)
5746 continue; /* nonexistent channel */
5747 if (c->type != CHAN_SOCKDATA_DORMANT)
5748 continue; /* dunno why they're failing this */
5749
5750 logevent("Forwarded connection refused by server");
5751
5752 pfd_close(c->u.pfd.s);
5753
51470298 5754 del234(ssh->channels, c);
724cface 5755 sfree(c);
51470298 5756 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_REQUEST) {
ebb0a590 5757 unsigned localid;
5758 char *type;
5759 int typelen, want_reply;
5760 struct ssh_channel *c;
5761
51470298 5762 localid = ssh2_pkt_getuint32(ssh);
5763 ssh2_pkt_getstring(ssh, &type, &typelen);
5764 want_reply = ssh2_pkt_getbool(ssh);
ebb0a590 5765
5766 /*
5767 * First, check that the channel exists. Otherwise,
5768 * we can instantly disconnect with a rude message.
5769 */
51470298 5770 c = find234(ssh->channels, &localid, ssh_channelfind);
ebb0a590 5771 if (!c) {
5772 char buf[80];
5773 sprintf(buf, "Received channel request for nonexistent"
5774 " channel %d", localid);
5775 logevent(buf);
51470298 5776 ssh2_pkt_init(ssh, SSH2_MSG_DISCONNECT);
5777 ssh2_pkt_adduint32(ssh, SSH2_DISCONNECT_BY_APPLICATION);
5778 ssh2_pkt_addstring(ssh, buf);
5779 ssh2_pkt_addstring(ssh, "en"); /* language tag */
5780 ssh2_pkt_send(ssh);
6b5cf8b4 5781 connection_fatal(ssh->frontend, "%s", buf);
3bb2f322 5782 ssh_closing((Plug)ssh, NULL, 0, 0);
ebb0a590 5783 crReturnV;
5784 }
5785
5786 /*
d8d6c7e5 5787 * Having got the channel number, we now look at
5788 * the request type string to see if it's something
5789 * we recognise.
ebb0a590 5790 */
d8d6c7e5 5791 if (typelen == 11 && !memcmp(type, "exit-status", 11) &&
51470298 5792 c == ssh->mainchan) {
d8d6c7e5 5793 /* We recognise "exit-status" on the primary channel. */
5794 char buf[100];
51470298 5795 ssh->exitcode = ssh2_pkt_getuint32(ssh);
d8d6c7e5 5796 sprintf(buf, "Server sent command exit status %d",
51470298 5797 ssh->exitcode);
d8d6c7e5 5798 logevent(buf);
5799 if (want_reply) {
51470298 5800 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_SUCCESS);
5801 ssh2_pkt_adduint32(ssh, c->remoteid);
5802 ssh2_pkt_send(ssh);
d8d6c7e5 5803 }
5804 } else {
5805 /*
5806 * This is a channel request we don't know
5807 * about, so we now either ignore the request
5808 * or respond with CHANNEL_FAILURE, depending
5809 * on want_reply.
5810 */
5811 if (want_reply) {
51470298 5812 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_FAILURE);
5813 ssh2_pkt_adduint32(ssh, c->remoteid);
5814 ssh2_pkt_send(ssh);
d8d6c7e5 5815 }
ebb0a590 5816 }
51470298 5817 } else if (ssh->pktin.type == SSH2_MSG_GLOBAL_REQUEST) {
697d4856 5818 char *type;
5819 int typelen, want_reply;
5820
51470298 5821 ssh2_pkt_getstring(ssh, &type, &typelen);
5822 want_reply = ssh2_pkt_getbool(ssh);
697d4856 5823
5824 /*
5825 * We currently don't support any global requests
5826 * at all, so we either ignore the request or
5827 * respond with REQUEST_FAILURE, depending on
5828 * want_reply.
5829 */
5830 if (want_reply) {
51470298 5831 ssh2_pkt_init(ssh, SSH2_MSG_REQUEST_FAILURE);
5832 ssh2_pkt_send(ssh);
697d4856 5833 }
51470298 5834 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_OPEN) {
32874aea 5835 char *type;
5836 int typelen;
b3ebaa28 5837 char *peeraddr;
5838 int peeraddrlen;
2e5b14c0 5839 int peerport;
32874aea 5840 char *error = NULL;
5841 struct ssh_channel *c;
bc240b21 5842 unsigned remid, winsize, pktsize;
51470298 5843 ssh2_pkt_getstring(ssh, &type, &typelen);
3d88e64d 5844 c = snew(struct ssh_channel);
51470298 5845 c->ssh = ssh;
32874aea 5846
51470298 5847 remid = ssh2_pkt_getuint32(ssh);
5848 winsize = ssh2_pkt_getuint32(ssh);
5849 pktsize = ssh2_pkt_getuint32(ssh);
bc240b21 5850
32874aea 5851 if (typelen == 3 && !memcmp(type, "x11", 3)) {
df85f78b 5852 char *addrstr;
5853
5854 ssh2_pkt_getstring(ssh, &peeraddr, &peeraddrlen);
5855 addrstr = snewn(peeraddrlen+1, char);
b3ebaa28 5856 memcpy(addrstr, peeraddr, peeraddrlen);
5857 peeraddr[peeraddrlen] = '\0';
2e5b14c0 5858 peerport = ssh2_pkt_getuint32(ssh);
b3ebaa28 5859
51470298 5860 if (!ssh->X11_fwd_enabled)
32874aea 5861 error = "X11 forwarding is not enabled";
86916870 5862 else if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
2e5b14c0 5863 ssh->x11auth, addrstr, peerport,
e8fa8f62 5864 &ssh->cfg) != NULL) {
32874aea 5865 error = "Unable to open an X11 connection";
5866 } else {
5867 c->type = CHAN_X11;
5868 }
b3ebaa28 5869
5870 sfree(addrstr);
bc240b21 5871 } else if (typelen == 15 &&
5872 !memcmp(type, "forwarded-tcpip", 15)) {
5873 struct ssh_rportfwd pf, *realpf;
5874 char *dummy;
5875 int dummylen;
51470298 5876 ssh2_pkt_getstring(ssh, &dummy, &dummylen);/* skip address */
5877 pf.sport = ssh2_pkt_getuint32(ssh);
2e5b14c0 5878 ssh2_pkt_getstring(ssh, &peeraddr, &peeraddrlen);
5879 peerport = ssh2_pkt_getuint32(ssh);
51470298 5880 realpf = find234(ssh->rportfwds, &pf, NULL);
bc240b21 5881 if (realpf == NULL) {
5882 error = "Remote port is not recognised";
5883 } else {
5884 char *e = pfd_newconnect(&c->u.pfd.s, realpf->dhost,
e8fa8f62 5885 realpf->dport, c, &ssh->cfg);
57356d63 5886 logeventf(ssh, "Received remote port open request"
5887 " for %s:%d", realpf->dhost, realpf->dport);
bc240b21 5888 if (e != NULL) {
57356d63 5889 logeventf(ssh, "Port open failed: %s", e);
bc240b21 5890 error = "Port open failed";
5891 } else {
5892 logevent("Forwarded port opened successfully");
5893 c->type = CHAN_SOCKDATA;
5894 }
5895 }
32874aea 5896 } else if (typelen == 22 &&
36c2a3e9 5897 !memcmp(type, "auth-agent@openssh.com", 3)) {
51470298 5898 if (!ssh->agentfwd_enabled)
32874aea 5899 error = "Agent forwarding is not enabled";
36c2a3e9 5900 else {
32874aea 5901 c->type = CHAN_AGENT; /* identify channel type */
36c2a3e9 5902 c->u.a.lensofar = 0;
32874aea 5903 }
5904 } else {
5905 error = "Unsupported channel type requested";
5906 }
5907
bc240b21 5908 c->remoteid = remid;
32874aea 5909 if (error) {
51470298 5910 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_OPEN_FAILURE);
5911 ssh2_pkt_adduint32(ssh, c->remoteid);
5912 ssh2_pkt_adduint32(ssh, SSH2_OPEN_CONNECT_FAILED);
5913 ssh2_pkt_addstring(ssh, error);
5914 ssh2_pkt_addstring(ssh, "en"); /* language tag */
5915 ssh2_pkt_send(ssh);
32874aea 5916 sfree(c);
5917 } else {
51470298 5918 c->localid = alloc_channel_id(ssh);
32874aea 5919 c->closes = 0;
5471d09a 5920 c->v.v2.locwindow = OUR_V2_WINSIZE;
5921 c->v.v2.remwindow = winsize;
5922 c->v.v2.remmaxpkt = pktsize;
5923 bufchain_init(&c->v.v2.outbuffer);
51470298 5924 add234(ssh->channels, c);
5925 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
5926 ssh2_pkt_adduint32(ssh, c->remoteid);
5927 ssh2_pkt_adduint32(ssh, c->localid);
5928 ssh2_pkt_adduint32(ssh, c->v.v2.locwindow);
5929 ssh2_pkt_adduint32(ssh, 0x4000UL); /* our max pkt size */
5930 ssh2_pkt_send(ssh);
32874aea 5931 }
7cca0d81 5932 } else {
6b5cf8b4 5933 bombout(("Strange packet received: type %d", ssh->pktin.type));
32874aea 5934 crReturnV;
7cca0d81 5935 }
5936 } else {
32874aea 5937 /*
5938 * We have spare data. Add it to the channel buffer.
5939 */
d8baa528 5940 ssh2_add_channel_data(ssh->mainchan, (char *)in, inlen);
51470298 5941 s->try_send = TRUE;
32874aea 5942 }
51470298 5943 if (s->try_send) {
32874aea 5944 int i;
5945 struct ssh_channel *c;
5946 /*
5947 * Try to send data on all channels if we can.
5948 */
51470298 5949 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
a6253970 5950 int bufsize;
5951 if (c->closes)
5952 continue; /* don't send on closing channels */
5953 bufsize = ssh2_try_send(c);
5471d09a 5954 if (bufsize == 0) {
5955 switch (c->type) {
5956 case CHAN_MAINSESSION:
5957 /* stdin need not receive an unthrottle
5958 * notification since it will be polled */
5959 break;
5960 case CHAN_X11:
5961 x11_unthrottle(c->u.x11.s);
5962 break;
5963 case CHAN_AGENT:
5964 /* agent sockets are request/response and need no
5965 * buffer management */
5966 break;
5967 case CHAN_SOCKDATA:
5968 pfd_unthrottle(c->u.pfd.s);
5969 break;
5970 }
5971 }
5972 }
7cca0d81 5973 }
e5574168 5974 }
5975
5976 crFinishV;
5977}
5978
5979/*
7cca0d81 5980 * Handle the top-level SSH2 protocol.
5981 */
51470298 5982static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
7cca0d81 5983{
51470298 5984 if (do_ssh2_transport(ssh, in, inlen, ispkt) == 0)
32874aea 5985 return;
51470298 5986 do_ssh2_authconn(ssh, in, inlen, ispkt);
7cca0d81 5987}
5988
5989/*
8df7a775 5990 * Called to set up the connection.
374330e2 5991 *
5992 * Returns an error message, or NULL on success.
374330e2 5993 */
51470298 5994static char *ssh_init(void *frontend_handle, void **backend_handle,
86916870 5995 Config *cfg,
887035a5 5996 char *host, int port, char **realhost, int nodelay)
32874aea 5997{
fb09bf1c 5998 char *p;
51470298 5999 Ssh ssh;
6000
3d88e64d 6001 ssh = snew(struct ssh_tag);
86916870 6002 ssh->cfg = *cfg; /* STRUCTURE COPY */
125105d1 6003 ssh->version = 0; /* when not ready yet */
51470298 6004 ssh->s = NULL;
6005 ssh->cipher = NULL;
371e569c 6006 ssh->v1_cipher_ctx = NULL;
0183b242 6007 ssh->crcda_ctx = NULL;
51470298 6008 ssh->cscipher = NULL;
371e569c 6009 ssh->cs_cipher_ctx = NULL;
51470298 6010 ssh->sccipher = NULL;
371e569c 6011 ssh->sc_cipher_ctx = NULL;
51470298 6012 ssh->csmac = NULL;
a8327734 6013 ssh->cs_mac_ctx = NULL;
51470298 6014 ssh->scmac = NULL;
e0e1a00d 6015 ssh->sc_mac_ctx = NULL;
51470298 6016 ssh->cscomp = NULL;
5366aed8 6017 ssh->cs_comp_ctx = NULL;
51470298 6018 ssh->sccomp = NULL;
5366aed8 6019 ssh->sc_comp_ctx = NULL;
51470298 6020 ssh->kex = NULL;
389aa499 6021 ssh->kex_ctx = NULL;
51470298 6022 ssh->hostkey = NULL;
6023 ssh->exitcode = -1;
6024 ssh->state = SSH_STATE_PREPACKET;
6025 ssh->size_needed = FALSE;
6026 ssh->eof_needed = FALSE;
b9d7bcad 6027 ssh->ldisc = NULL;
a8327734 6028 ssh->logctx = NULL;
51470298 6029 {
6030 static const struct Packet empty = { 0, 0, NULL, NULL, 0 };
6031 ssh->pktin = ssh->pktout = empty;
6032 }
6033 ssh->deferred_send_data = NULL;
6034 ssh->deferred_len = 0;
6035 ssh->deferred_size = 0;
6036 ssh->fallback_cmd = 0;
6037 ssh->pkt_ctx = 0;
302121de 6038 ssh->x11auth = NULL;
be738459 6039 ssh->v1_compressing = FALSE;
51470298 6040 ssh->v2_outgoing_sequence = 0;
6041 ssh->ssh1_rdpkt_crstate = 0;
6042 ssh->ssh2_rdpkt_crstate = 0;
6043 ssh->do_ssh_init_crstate = 0;
6044 ssh->ssh_gotdata_crstate = 0;
6045 ssh->ssh1_protocol_crstate = 0;
6046 ssh->do_ssh1_login_crstate = 0;
6047 ssh->do_ssh2_transport_crstate = 0;
6048 ssh->do_ssh2_authconn_crstate = 0;
6049 ssh->do_ssh_init_state = NULL;
6050 ssh->do_ssh1_login_state = NULL;
6051 ssh->do_ssh2_transport_state = NULL;
6052 ssh->do_ssh2_authconn_state = NULL;
6571dbfd 6053 ssh->mainchan = NULL;
968d2d92 6054 ssh->throttled_all = 0;
6055 ssh->v1_stdout_throttling = 0;
51470298 6056
6057 *backend_handle = ssh;
32874aea 6058
8f203108 6059#ifdef MSCRYPTOAPI
32874aea 6060 if (crypto_startup() == 0)
8f203108 6061 return "Microsoft high encryption pack not installed!";
6062#endif
374330e2 6063
51470298 6064 ssh->frontend = frontend_handle;
86916870 6065 ssh->term_width = ssh->cfg.width;
6066 ssh->term_height = ssh->cfg.height;
887035a5 6067
fabd1805 6068 ssh->channels = NULL;
6069 ssh->rportfwds = NULL;
6070
51470298 6071 ssh->send_ok = 0;
6072 ssh->editing = 0;
6073 ssh->echoing = 0;
6074 ssh->v1_throttle_count = 0;
6075 ssh->overall_bufsize = 0;
6076 ssh->fallback_cmd = 0;
8df7a775 6077
3648d4c5 6078 ssh->protocol = NULL;
6079
51470298 6080 p = connect_to_host(ssh, host, port, realhost, nodelay);
fb09bf1c 6081 if (p != NULL)
6082 return p;
374330e2 6083
374330e2 6084 return NULL;
6085}
6086
fabd1805 6087static void ssh_free(void *handle)
6088{
6089 Ssh ssh = (Ssh) handle;
6090 struct ssh_channel *c;
6091 struct ssh_rportfwd *pf;
6092
6093 if (ssh->v1_cipher_ctx)
6094 ssh->cipher->free_context(ssh->v1_cipher_ctx);
6095 if (ssh->cs_cipher_ctx)
6096 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
6097 if (ssh->sc_cipher_ctx)
6098 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
6099 if (ssh->cs_mac_ctx)
6100 ssh->csmac->free_context(ssh->cs_mac_ctx);
6101 if (ssh->sc_mac_ctx)
6102 ssh->scmac->free_context(ssh->sc_mac_ctx);
6103 if (ssh->cs_comp_ctx)
6104 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
6105 if (ssh->sc_comp_ctx)
6106 ssh->sccomp->compress_cleanup(ssh->sc_comp_ctx);
6107 if (ssh->kex_ctx)
6108 dh_cleanup(ssh->kex_ctx);
6109 sfree(ssh->savedhost);
6110
6111 if (ssh->channels) {
6112 while ((c = delpos234(ssh->channels, 0)) != NULL) {
6113 switch (c->type) {
6114 case CHAN_X11:
6115 if (c->u.x11.s != NULL)
6116 x11_close(c->u.x11.s);
6117 break;
6118 case CHAN_SOCKDATA:
6119 if (c->u.pfd.s != NULL)
6120 pfd_close(c->u.pfd.s);
6121 break;
6122 }
6123 sfree(c);
6124 }
6125 freetree234(ssh->channels);
6126 }
6127
6128 if (ssh->rportfwds) {
6129 while ((pf = delpos234(ssh->rportfwds, 0)) != NULL)
6130 sfree(pf);
6131 freetree234(ssh->rportfwds);
6132 }
6133 sfree(ssh->deferred_send_data);
6134 if (ssh->x11auth)
6135 x11_free_auth(ssh->x11auth);
6136 sfree(ssh->do_ssh_init_state);
6137 sfree(ssh->do_ssh1_login_state);
6138 sfree(ssh->do_ssh2_transport_state);
6139 sfree(ssh->do_ssh2_authconn_state);
6140
6141 if (ssh->s)
6142 sk_close(ssh->s);
6143 sfree(ssh);
6144}
6145
374330e2 6146/*
86916870 6147 * Reconfigure the SSH backend.
6148 *
6149 * Currently, this function does nothing very useful. In future,
6150 * however, we could do some handy things with it. For example, we
6151 * could make the port forwarding configurer active in the Change
6152 * Settings box, and this routine could close down existing
6153 * forwardings and open up new ones in response to changes.
6154 */
6155static void ssh_reconfig(void *handle, Config *cfg)
6156{
6157 Ssh ssh = (Ssh) handle;
6158 ssh->cfg = *cfg; /* STRUCTURE COPY */
6159}
6160
6161/*
374330e2 6162 * Called to send data down the Telnet connection.
6163 */
51470298 6164static int ssh_send(void *handle, char *buf, int len)
32874aea 6165{
51470298 6166 Ssh ssh = (Ssh) handle;
6167
6168 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
5471d09a 6169 return 0;
374330e2 6170
d8baa528 6171 ssh->protocol(ssh, (unsigned char *)buf, len, 0);
5471d09a 6172
51470298 6173 return ssh_sendbuffer(ssh);
5471d09a 6174}
6175
6176/*
6177 * Called to query the current amount of buffered stdin data.
6178 */
51470298 6179static int ssh_sendbuffer(void *handle)
5471d09a 6180{
51470298 6181 Ssh ssh = (Ssh) handle;
5471d09a 6182 int override_value;
6183
51470298 6184 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
5471d09a 6185 return 0;
6186
6187 /*
6188 * If the SSH socket itself has backed up, add the total backup
6189 * size on that to any individual buffer on the stdin channel.
6190 */
6191 override_value = 0;
51470298 6192 if (ssh->throttled_all)
6193 override_value = ssh->overall_bufsize;
5471d09a 6194
51470298 6195 if (ssh->version == 1) {
5471d09a 6196 return override_value;
51470298 6197 } else if (ssh->version == 2) {
6198 if (!ssh->mainchan || ssh->mainchan->closes > 0)
5471d09a 6199 return override_value;
6200 else
51470298 6201 return (override_value +
6202 bufchain_size(&ssh->mainchan->v.v2.outbuffer));
5471d09a 6203 }
6204
6205 return 0;
374330e2 6206}
6207
6208/*
6e48c3fe 6209 * Called to set the size of the window from SSH's POV.
374330e2 6210 */
51470298 6211static void ssh_size(void *handle, int width, int height)
32874aea 6212{
51470298 6213 Ssh ssh = (Ssh) handle;
6214
6215 ssh->term_width = width;
6216 ssh->term_height = height;
f278d6f8 6217
51470298 6218 switch (ssh->state) {
374330e2 6219 case SSH_STATE_BEFORE_SIZE:
3687d221 6220 case SSH_STATE_PREPACKET:
21248260 6221 case SSH_STATE_CLOSED:
374330e2 6222 break; /* do nothing */
6223 case SSH_STATE_INTERMED:
51470298 6224 ssh->size_needed = TRUE; /* buffer for later */
374330e2 6225 break;
6226 case SSH_STATE_SESSION:
86916870 6227 if (!ssh->cfg.nopty) {
51470298 6228 if (ssh->version == 1) {
6229 send_packet(ssh, SSH1_CMSG_WINDOW_SIZE,
6230 PKT_INT, ssh->term_height,
6231 PKT_INT, ssh->term_width,
32874aea 6232 PKT_INT, 0, PKT_INT, 0, PKT_END);
6233 } else {
51470298 6234 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
6235 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
6236 ssh2_pkt_addstring(ssh, "window-change");
6237 ssh2_pkt_addbool(ssh, 0);
6238 ssh2_pkt_adduint32(ssh, ssh->term_width);
6239 ssh2_pkt_adduint32(ssh, ssh->term_height);
6240 ssh2_pkt_adduint32(ssh, 0);
6241 ssh2_pkt_adduint32(ssh, 0);
6242 ssh2_pkt_send(ssh);
32874aea 6243 }
6244 }
6245 break;
374330e2 6246 }
6247}
6248
6249/*
125105d1 6250 * Return a list of the special codes that make sense in this
6251 * protocol.
6252 */
6253static const struct telnet_special *ssh_get_specials(void *handle)
6254{
6255 Ssh ssh = (Ssh) handle;
6256
6257 if (ssh->version == 1) {
6258 static const struct telnet_special ssh1_specials[] = {
6259 {"IGNORE message", TS_NOP},
6260 {NULL, 0}
6261 };
6262 return ssh1_specials;
6263 } else if (ssh->version == 2) {
6264 static const struct telnet_special ssh2_specials[] = {
6265 {"Break", TS_BRK},
6266 {"IGNORE message", TS_NOP},
6267 {NULL, 0}
6268 };
6269 return ssh2_specials;
6270 } else
6271 return NULL;
6272}
6273
6274/*
6abbf9e3 6275 * Send Telnet special codes. TS_EOF is useful for `plink', so you
6276 * can send an EOF and collect resulting output (e.g. `plink
6277 * hostname sort').
374330e2 6278 */
51470298 6279static void ssh_special(void *handle, Telnet_Special code)
32874aea 6280{
51470298 6281 Ssh ssh = (Ssh) handle;
6282
6abbf9e3 6283 if (code == TS_EOF) {
51470298 6284 if (ssh->state != SSH_STATE_SESSION) {
32874aea 6285 /*
6286 * Buffer the EOF in case we are pre-SESSION, so we can
6287 * send it as soon as we reach SESSION.
6288 */
6289 if (code == TS_EOF)
51470298 6290 ssh->eof_needed = TRUE;
32874aea 6291 return;
6292 }
51470298 6293 if (ssh->version == 1) {
6294 send_packet(ssh, SSH1_CMSG_EOF, PKT_END);
32874aea 6295 } else {
51470298 6296 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_EOF);
6297 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
6298 ssh2_pkt_send(ssh);
32874aea 6299 }
6300 logevent("Sent EOF message");
125105d1 6301 } else if (code == TS_PING || code == TS_NOP) {
51470298 6302 if (ssh->state == SSH_STATE_CLOSED
6303 || ssh->state == SSH_STATE_PREPACKET) return;
6304 if (ssh->version == 1) {
6305 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE))
6306 send_packet(ssh, SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
32874aea 6307 } else {
51470298 6308 ssh2_pkt_init(ssh, SSH2_MSG_IGNORE);
6309 ssh2_pkt_addstring_start(ssh);
6310 ssh2_pkt_send(ssh);
32874aea 6311 }
125105d1 6312 } else if (code == TS_BRK) {
6313 if (ssh->state == SSH_STATE_CLOSED
6314 || ssh->state == SSH_STATE_PREPACKET) return;
6315 if (ssh->version == 1) {
6316 logevent("Unable to send BREAK signal in SSH1");
6317 } else {
6318 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
6319 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
6320 ssh2_pkt_addstring(ssh, "break");
6321 ssh2_pkt_addbool(ssh, 0);
6322 ssh2_pkt_adduint32(ssh, 0); /* default break length */
6323 ssh2_pkt_send(ssh);
6324 }
6abbf9e3 6325 } else {
32874aea 6326 /* do nothing */
6abbf9e3 6327 }
374330e2 6328}
6329
51470298 6330void *new_sock_channel(void *handle, Socket s)
d74d141c 6331{
51470298 6332 Ssh ssh = (Ssh) handle;
d74d141c 6333 struct ssh_channel *c;
3d88e64d 6334 c = snew(struct ssh_channel);
51470298 6335 c->ssh = ssh;
d74d141c 6336
6337 if (c) {
bc240b21 6338 c->remoteid = -1; /* to be set when open confirmed */
51470298 6339 c->localid = alloc_channel_id(ssh);
d74d141c 6340 c->closes = 0;
bc240b21 6341 c->type = CHAN_SOCKDATA_DORMANT;/* identify channel type */
d74d141c 6342 c->u.pfd.s = s;
013dd8c0 6343 bufchain_init(&c->v.v2.outbuffer);
51470298 6344 add234(ssh->channels, c);
d74d141c 6345 }
6346 return c;
6347}
6348
5471d09a 6349/*
6350 * This is called when stdout/stderr (the entity to which
6351 * from_backend sends data) manages to clear some backlog.
6352 */
ae9ae89f 6353static void ssh_unthrottle(void *handle, int bufsize)
5471d09a 6354{
51470298 6355 Ssh ssh = (Ssh) handle;
6356 if (ssh->version == 1) {
6357 if (ssh->v1_stdout_throttling && bufsize < SSH1_BUFFER_LIMIT) {
6358 ssh->v1_stdout_throttling = 0;
6359 ssh1_throttle(ssh, -1);
5471d09a 6360 }
6361 } else {
51470298 6362 if (ssh->mainchan && ssh->mainchan->closes == 0)
6363 ssh2_set_window(ssh->mainchan, OUR_V2_WINSIZE - bufsize);
5471d09a 6364 }
6365}
6366
6b78788a 6367void ssh_send_port_open(void *channel, char *hostname, int port, char *org)
d74d141c 6368{
6369 struct ssh_channel *c = (struct ssh_channel *)channel;
6b78788a 6370 Ssh ssh = c->ssh;
d74d141c 6371
57356d63 6372 logeventf(ssh, "Opening forwarded connection to %s:%d", hostname, port);
d74d141c 6373
51470298 6374 if (ssh->version == 1) {
6375 send_packet(ssh, SSH1_MSG_PORT_OPEN,
bc240b21 6376 PKT_INT, c->localid,
6377 PKT_STR, hostname,
6378 PKT_INT, port,
6379 //PKT_STR, <org:orgport>,
6380 PKT_END);
6381 } else {
51470298 6382 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_OPEN);
6383 ssh2_pkt_addstring(ssh, "direct-tcpip");
6384 ssh2_pkt_adduint32(ssh, c->localid);
5471d09a 6385 c->v.v2.locwindow = OUR_V2_WINSIZE;
51470298 6386 ssh2_pkt_adduint32(ssh, c->v.v2.locwindow);/* our window size */
6387 ssh2_pkt_adduint32(ssh, 0x4000UL); /* our max pkt size */
6388 ssh2_pkt_addstring(ssh, hostname);
6389 ssh2_pkt_adduint32(ssh, port);
bc240b21 6390 /*
6391 * We make up values for the originator data; partly it's
6392 * too much hassle to keep track, and partly I'm not
6393 * convinced the server should be told details like that
6394 * about my local network configuration.
6395 */
51470298 6396 ssh2_pkt_addstring(ssh, "client-side-connection");
6397 ssh2_pkt_adduint32(ssh, 0);
6398 ssh2_pkt_send(ssh);
bc240b21 6399 }
d74d141c 6400}
6401
6402
51470298 6403static Socket ssh_socket(void *handle)
32874aea 6404{
51470298 6405 Ssh ssh = (Ssh) handle;
6406 return ssh->s;
32874aea 6407}
8ccc75b0 6408
51470298 6409static int ssh_sendok(void *handle)
32874aea 6410{
51470298 6411 Ssh ssh = (Ssh) handle;
6412 return ssh->send_ok;
32874aea 6413}
fb09bf1c 6414
51470298 6415static int ssh_ldisc(void *handle, int option)
32874aea 6416{
51470298 6417 Ssh ssh = (Ssh) handle;
32874aea 6418 if (option == LD_ECHO)
51470298 6419 return ssh->echoing;
32874aea 6420 if (option == LD_EDIT)
51470298 6421 return ssh->editing;
0965bee0 6422 return FALSE;
6423}
6424
b9d7bcad 6425static void ssh_provide_ldisc(void *handle, void *ldisc)
6426{
6427 Ssh ssh = (Ssh) handle;
6428 ssh->ldisc = ldisc;
6429}
6430
a8327734 6431static void ssh_provide_logctx(void *handle, void *logctx)
6432{
6433 Ssh ssh = (Ssh) handle;
6434 ssh->logctx = logctx;
6435}
6436
51470298 6437static int ssh_return_exitcode(void *handle)
6438{
6439 Ssh ssh = (Ssh) handle;
3bb2f322 6440 if (ssh->s != NULL)
6441 return -1;
6442 else
6443 return (ssh->exitcode >= 0 ? ssh->exitcode : 0);
51470298 6444}
6445
6446/*
6447 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
6448 * that fails. This variable is the means by which scp.c can reach
6449 * into the SSH code and find out which one it got.
6450 */
6451extern int ssh_fallback_cmd(void *handle)
d8d6c7e5 6452{
51470298 6453 Ssh ssh = (Ssh) handle;
6454 return ssh->fallback_cmd;
d8d6c7e5 6455}
6456
374330e2 6457Backend ssh_backend = {
6458 ssh_init,
fabd1805 6459 ssh_free,
86916870 6460 ssh_reconfig,
374330e2 6461 ssh_send,
5471d09a 6462 ssh_sendbuffer,
374330e2 6463 ssh_size,
4017be6d 6464 ssh_special,
125105d1 6465 ssh_get_specials,
8ccc75b0 6466 ssh_socket,
d8d6c7e5 6467 ssh_return_exitcode,
97db3be4 6468 ssh_sendok,
0965bee0 6469 ssh_ldisc,
b9d7bcad 6470 ssh_provide_ldisc,
a8327734 6471 ssh_provide_logctx,
5471d09a 6472 ssh_unthrottle,
97db3be4 6473 22
bc240b21 6474};
Local modifications for Simon Tatham's `PuTTY' SSH client and terminal emulator