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The divisor in the bell timing boxes should be TICKSPERSEC, not 1000.
[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.
280 */
51470298 281#define crBegin(v) { int *crLine = &v; switch(v) { case 0:;
282#define crState(t) \
283 struct t *s; \
284 if (!ssh->t) ssh->t = smalloc(sizeof(struct t)); \
285 s = ssh->t;
286#define crFinish(z) } *crLine = 0; return (z); }
287#define crFinishV } *crLine = 0; return; }
374330e2 288#define crReturn(z) \
289 do {\
51470298 290 *crLine =__LINE__; return (z); case __LINE__:;\
374330e2 291 } while (0)
292#define crReturnV \
293 do {\
51470298 294 *crLine=__LINE__; return; case __LINE__:;\
374330e2 295 } while (0)
51470298 296#define crStop(z) do{ *crLine = 0; return (z); }while(0)
297#define crStopV do{ *crLine = 0; return; }while(0)
fb09bf1c 298#define crWaitUntil(c) do { crReturn(0); } while (!(c))
7cca0d81 299#define crWaitUntilV(c) do { crReturnV; } while (!(c))
374330e2 300
51470298 301typedef struct ssh_tag *Ssh;
302
51470298 303static void ssh2_pkt_init(Ssh, int pkt_type);
304static void ssh2_pkt_addbool(Ssh, unsigned char value);
305static void ssh2_pkt_adduint32(Ssh, unsigned long value);
306static void ssh2_pkt_addstring_start(Ssh);
307static void ssh2_pkt_addstring_str(Ssh, char *data);
308static void ssh2_pkt_addstring_data(Ssh, char *data, int len);
309static void ssh2_pkt_addstring(Ssh, char *data);
d8baa528 310static unsigned char *ssh2_mpint_fmt(Bignum b, int *len);
51470298 311static void ssh2_pkt_addmp(Ssh, Bignum b);
312static int ssh2_pkt_construct(Ssh);
313static void ssh2_pkt_send(Ssh);
3d63ca2e 314
5471d09a 315/*
316 * Buffer management constants. There are several of these for
317 * various different purposes:
318 *
319 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
320 * on a local data stream before we throttle the whole SSH
321 * connection (in SSH1 only). Throttling the whole connection is
322 * pretty drastic so we set this high in the hope it won't
323 * happen very often.
324 *
325 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
326 * on the SSH connection itself before we defensively throttle
327 * _all_ local data streams. This is pretty drastic too (though
328 * thankfully unlikely in SSH2 since the window mechanism should
329 * ensure that the server never has any need to throttle its end
330 * of the connection), so we set this high as well.
331 *
332 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
333 * channels.
334 */
335
336#define SSH1_BUFFER_LIMIT 32768
337#define SSH_MAX_BACKLOG 32768
338#define OUR_V2_WINSIZE 16384
d74d141c 339
a92dd380 340const static struct ssh_kex *kex_algs[] = {
a92dd380 341 &ssh_diffiehellman_gex,
32874aea 342 &ssh_diffiehellman
343};
e5574168 344
85cc02bb 345const static struct ssh_signkey *hostkey_algs[] = { &ssh_rsa, &ssh_dss };
e5574168 346
e0e1a00d 347static void *nullmac_make_context(void)
348{
349 return NULL;
350}
351static void nullmac_free_context(void *handle)
352{
353}
354static void nullmac_key(void *handle, unsigned char *key)
32874aea 355{
356}
e0e1a00d 357static void nullmac_generate(void *handle, unsigned char *blk, int len,
32874aea 358 unsigned long seq)
359{
360}
e0e1a00d 361static int nullmac_verify(void *handle, unsigned char *blk, int len,
362 unsigned long seq)
32874aea 363{
364 return 1;
365}
57476f6b 366const static struct ssh_mac ssh_mac_none = {
e0e1a00d 367 nullmac_make_context, nullmac_free_context, nullmac_key,
368 nullmac_generate, nullmac_verify, "none", 0
e5574168 369};
8b2715b2 370const static struct ssh_mac *macs[] = {
32874aea 371 &ssh_sha1, &ssh_md5, &ssh_mac_none
372};
8b2715b2 373const static struct ssh_mac *buggymacs[] = {
32874aea 374 &ssh_sha1_buggy, &ssh_md5, &ssh_mac_none
375};
e5574168 376
5366aed8 377static void *ssh_comp_none_init(void)
378{
379 return NULL;
380}
381static void ssh_comp_none_cleanup(void *handle)
32874aea 382{
383}
5366aed8 384static int ssh_comp_none_block(void *handle, unsigned char *block, int len,
32874aea 385 unsigned char **outblock, int *outlen)
386{
387 return 0;
388}
5366aed8 389static int ssh_comp_none_disable(void *handle)
32874aea 390{
4ba9b64b 391 return 0;
392}
57476f6b 393const static struct ssh_compress ssh_comp_none = {
4ba9b64b 394 "none",
5366aed8 395 ssh_comp_none_init, ssh_comp_none_cleanup, ssh_comp_none_block,
396 ssh_comp_none_init, ssh_comp_none_cleanup, ssh_comp_none_block,
397 ssh_comp_none_disable, NULL
e5574168 398};
4ba9b64b 399extern const struct ssh_compress ssh_zlib;
400const static struct ssh_compress *compressions[] = {
32874aea 401 &ssh_zlib, &ssh_comp_none
402};
374330e2 403
32874aea 404enum { /* channel types */
783415f8 405 CHAN_MAINSESSION,
406 CHAN_X11,
407 CHAN_AGENT,
bc240b21 408 CHAN_SOCKDATA,
409 CHAN_SOCKDATA_DORMANT /* one the remote hasn't confirmed */
783415f8 410};
411
dacbd0e8 412/*
413 * 2-3-4 tree storing channels.
414 */
415struct ssh_channel {
51470298 416 Ssh ssh; /* pointer back to main context */
d211621f 417 unsigned remoteid, localid;
dacbd0e8 418 int type;
0357890f 419 /*
420 * In SSH1, this value contains four bits:
421 *
422 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
423 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
424 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
425 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
426 *
427 * A channel is completely finished with when all four bits are set.
428 */
dacbd0e8 429 int closes;
5471d09a 430 union {
431 struct ssh1_data_channel {
432 int throttling;
433 } v1;
434 struct ssh2_data_channel {
435 bufchain outbuffer;
436 unsigned remwindow, remmaxpkt;
437 unsigned locwindow;
438 } v2;
439 } v;
dacbd0e8 440 union {
32874aea 441 struct ssh_agent_channel {
442 unsigned char *message;
443 unsigned char msglen[4];
444 int lensofar, totallen;
445 } a;
446 struct ssh_x11_channel {
447 Socket s;
448 } x11;
d74d141c 449 struct ssh_pfd_channel {
450 Socket s;
451 } pfd;
dacbd0e8 452 } u;
453};
57476f6b 454
d74d141c 455/*
bc240b21 456 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
457 * 2 use this structure in different ways, reflecting SSH 2's
458 * altogether saner approach to port forwarding.
459 *
460 * In SSH 1, you arrange a remote forwarding by sending the server
461 * the remote port number, and the local destination host:port.
462 * When a connection comes in, the server sends you back that
463 * host:port pair, and you connect to it. This is a ready-made
464 * security hole if you're not on the ball: a malicious server
465 * could send you back _any_ host:port pair, so if you trustingly
466 * connect to the address it gives you then you've just opened the
467 * entire inside of your corporate network just by connecting
468 * through it to a dodgy SSH server. Hence, we must store a list of
469 * host:port pairs we _are_ trying to forward to, and reject a
470 * connection request from the server if it's not in the list.
471 *
472 * In SSH 2, each side of the connection minds its own business and
473 * doesn't send unnecessary information to the other. You arrange a
474 * remote forwarding by sending the server just the remote port
475 * number. When a connection comes in, the server tells you which
476 * of its ports was connected to; and _you_ have to remember what
477 * local host:port pair went with that port number.
478 *
479 * Hence: in SSH 1 this structure stores host:port pairs we intend
480 * to allow connections to, and is indexed by those host:port
481 * pairs. In SSH 2 it stores a mapping from source port to
482 * destination host:port pair, and is indexed by source port.
d74d141c 483 */
484struct ssh_rportfwd {
bc240b21 485 unsigned sport, dport;
486 char dhost[256];
d74d141c 487};
488
57476f6b 489struct Packet {
490 long length;
491 int type;
492 unsigned char *data;
493 unsigned char *body;
494 long savedpos;
495 long maxlen;
496};
497
51470298 498static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt);
499static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt);
500static void ssh_size(void *handle, int width, int height);
501static void ssh_special(void *handle, Telnet_Special);
5471d09a 502static int ssh2_try_send(struct ssh_channel *c);
51470298 503static void ssh2_add_channel_data(struct ssh_channel *c, char *buf, int len);
504static void ssh_throttle_all(Ssh ssh, int enable, int bufsize);
5471d09a 505static void ssh2_set_window(struct ssh_channel *c, unsigned newwin);
51470298 506static int ssh_sendbuffer(void *handle);
57476f6b 507
51470298 508struct rdpkt1_state_tag {
57476f6b 509 long len, pad, biglen, to_read;
510 unsigned long realcrc, gotcrc;
511 unsigned char *p;
512 int i;
513 int chunk;
51470298 514};
57476f6b 515
51470298 516struct rdpkt2_state_tag {
960e736a 517 long len, pad, payload, packetlen, maclen;
518 int i;
519 int cipherblk;
520 unsigned long incoming_sequence;
51470298 521};
522
523struct ssh_tag {
524 const struct plug_function_table *fn;
525 /* the above field _must_ be first in the structure */
526
527 SHA_State exhash, exhashbase;
528
529 Socket s;
530
b9d7bcad 531 void *ldisc;
a8327734 532 void *logctx;
b9d7bcad 533
51470298 534 unsigned char session_key[32];
535 int v1_compressing;
536 int v1_remote_protoflags;
537 int v1_local_protoflags;
538 int agentfwd_enabled;
539 int X11_fwd_enabled;
540 int remote_bugs;
541 const struct ssh_cipher *cipher;
371e569c 542 void *v1_cipher_ctx;
0183b242 543 void *crcda_ctx;
51470298 544 const struct ssh2_cipher *cscipher, *sccipher;
371e569c 545 void *cs_cipher_ctx, *sc_cipher_ctx;
51470298 546 const struct ssh_mac *csmac, *scmac;
e0e1a00d 547 void *cs_mac_ctx, *sc_mac_ctx;
51470298 548 const struct ssh_compress *cscomp, *sccomp;
5366aed8 549 void *cs_comp_ctx, *sc_comp_ctx;
51470298 550 const struct ssh_kex *kex;
551 const struct ssh_signkey *hostkey;
552 unsigned char v2_session_id[20];
27cd7fc2 553 void *kex_ctx;
51470298 554
555 char *savedhost;
556 int savedport;
557 int send_ok;
558 int echoing, editing;
559
560 void *frontend;
561
562 int term_width, term_height;
563
564 tree234 *channels; /* indexed by local id */
565 struct ssh_channel *mainchan; /* primary session channel */
566 int exitcode;
567
568 tree234 *rportfwds;
569
570 enum {
571 SSH_STATE_PREPACKET,
572 SSH_STATE_BEFORE_SIZE,
573 SSH_STATE_INTERMED,
574 SSH_STATE_SESSION,
575 SSH_STATE_CLOSED
576 } state;
577
578 int size_needed, eof_needed;
579
580 struct Packet pktin;
581 struct Packet pktout;
582 unsigned char *deferred_send_data;
583 int deferred_len, deferred_size;
584
585 /*
586 * Gross hack: pscp will try to start SFTP but fall back to
587 * scp1 if that fails. This variable is the means by which
588 * scp.c can reach into the SSH code and find out which one it
589 * got.
590 */
591 int fallback_cmd;
592
593 /*
594 * Used for username and password input.
595 */
596 char *userpass_input_buffer;
597 int userpass_input_buflen;
598 int userpass_input_bufpos;
599 int userpass_input_echo;
600
601 char *portfwd_strptr;
602 int pkt_ctx;
603
302121de 604 void *x11auth;
605
51470298 606 int version;
607 int v1_throttle_count;
608 int overall_bufsize;
609 int throttled_all;
610 int v1_stdout_throttling;
611 int v2_outgoing_sequence;
612
613 int ssh1_rdpkt_crstate;
614 int ssh2_rdpkt_crstate;
615 int do_ssh_init_crstate;
616 int ssh_gotdata_crstate;
617 int ssh1_protocol_crstate;
618 int do_ssh1_login_crstate;
619 int do_ssh2_transport_crstate;
620 int do_ssh2_authconn_crstate;
621
622 void *do_ssh_init_state;
623 void *do_ssh1_login_state;
624 void *do_ssh2_transport_state;
625 void *do_ssh2_authconn_state;
626
627 struct rdpkt1_state_tag rdpkt1_state;
628 struct rdpkt2_state_tag rdpkt2_state;
629
630 void (*protocol) (Ssh ssh, unsigned char *in, int inlen, int ispkt);
631 int (*s_rdpkt) (Ssh ssh, unsigned char **data, int *datalen);
86916870 632
633 /*
634 * We maintain a full _copy_ of a Config structure here, not
635 * merely a pointer to it. That way, when we're passed a new
636 * one for reconfiguration, we can check the differences and
637 * potentially reconfigure port forwardings etc in mid-session.
638 */
639 Config cfg;
51470298 640};
960e736a 641
382908ad 642#define logevent(s) logevent(ssh->frontend, s)
a8327734 643
644/* logevent, only printf-formatted. */
ae9ae89f 645static void logeventf(Ssh ssh, char *fmt, ...)
a8327734 646{
647 va_list ap;
57356d63 648 char *buf;
a8327734 649
650 va_start(ap, fmt);
57356d63 651 buf = dupvprintf(fmt, ap);
a8327734 652 va_end(ap);
57356d63 653 logevent(buf);
57356d63 654 sfree(buf);
a8327734 655}
656
657#define bombout(msg) ( ssh->state = SSH_STATE_CLOSED, \
658 (ssh->s ? sk_close(ssh->s), ssh->s = NULL : 0), \
659 logeventf msg, connection_fatal msg )
660
32874aea 661static int ssh_channelcmp(void *av, void *bv)
662{
663 struct ssh_channel *a = (struct ssh_channel *) av;
664 struct ssh_channel *b = (struct ssh_channel *) bv;
665 if (a->localid < b->localid)
666 return -1;
667 if (a->localid > b->localid)
668 return +1;
dacbd0e8 669 return 0;
670}
32874aea 671static int ssh_channelfind(void *av, void *bv)
672{
673 unsigned *a = (unsigned *) av;
674 struct ssh_channel *b = (struct ssh_channel *) bv;
675 if (*a < b->localid)
676 return -1;
677 if (*a > b->localid)
678 return +1;
dacbd0e8 679 return 0;
680}
681
bc240b21 682static int ssh_rportcmp_ssh1(void *av, void *bv)
d74d141c 683{
684 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
685 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
686 int i;
bc240b21 687 if ( (i = strcmp(a->dhost, b->dhost)) != 0)
d74d141c 688 return i < 0 ? -1 : +1;
bc240b21 689 if (a->dport > b->dport)
690 return +1;
691 if (a->dport < b->dport)
692 return -1;
693 return 0;
694}
695
696static int ssh_rportcmp_ssh2(void *av, void *bv)
697{
698 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
699 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
cdcbdf3b 700
bc240b21 701 if (a->sport > b->sport)
d74d141c 702 return +1;
bc240b21 703 if (a->sport < b->sport)
704 return -1;
d74d141c 705 return 0;
706}
707
51470298 708static int alloc_channel_id(Ssh ssh)
32874aea 709{
260f3dec 710 const unsigned CHANNEL_NUMBER_OFFSET = 256;
711 unsigned low, high, mid;
d2371c81 712 int tsize;
713 struct ssh_channel *c;
714
715 /*
716 * First-fit allocation of channel numbers: always pick the
717 * lowest unused one. To do this, binary-search using the
718 * counted B-tree to find the largest channel ID which is in a
719 * contiguous sequence from the beginning. (Precisely
720 * everything in that sequence must have ID equal to its tree
721 * index plus CHANNEL_NUMBER_OFFSET.)
722 */
51470298 723 tsize = count234(ssh->channels);
d2371c81 724
32874aea 725 low = -1;
726 high = tsize;
d2371c81 727 while (high - low > 1) {
728 mid = (high + low) / 2;
51470298 729 c = index234(ssh->channels, mid);
d2371c81 730 if (c->localid == mid + CHANNEL_NUMBER_OFFSET)
731 low = mid; /* this one is fine */
732 else
733 high = mid; /* this one is past it */
734 }
735 /*
736 * Now low points to either -1, or the tree index of the
737 * largest ID in the initial sequence.
738 */
739 {
740 unsigned i = low + 1 + CHANNEL_NUMBER_OFFSET;
51470298 741 assert(NULL == find234(ssh->channels, &i, ssh_channelfind));
d2371c81 742 }
743 return low + 1 + CHANNEL_NUMBER_OFFSET;
744}
745
9fab77dc 746static void c_write(Ssh ssh, const char *buf, int len)
32874aea 747{
67779be7 748 if ((flags & FLAG_STDERR)) {
32874aea 749 int i;
750 for (i = 0; i < len; i++)
751 if (buf[i] != '\r')
752 fputc(buf[i], stderr);
fb09bf1c 753 return;
754 }
51470298 755 from_backend(ssh->frontend, 1, buf, len);
3bdaf79d 756}
757
9fab77dc 758static void c_write_untrusted(Ssh ssh, const char *buf, int len)
32874aea 759{
a209e957 760 int i;
761 for (i = 0; i < len; i++) {
32874aea 762 if (buf[i] == '\n')
51470298 763 c_write(ssh, "\r\n", 2);
32874aea 764 else if ((buf[i] & 0x60) || (buf[i] == '\r'))
51470298 765 c_write(ssh, buf + i, 1);
a209e957 766 }
767}
768
9fab77dc 769static void c_write_str(Ssh ssh, const char *buf)
32874aea 770{
51470298 771 c_write(ssh, buf, strlen(buf));
1408a877 772}
773
fb09bf1c 774/*
775 * Collect incoming data in the incoming packet buffer.
e5574168 776 * Decipher and verify the packet when it is completely read.
777 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
fb09bf1c 778 * Update the *data and *datalen variables.
779 * Return the additional nr of bytes needed, or 0 when
780 * a complete packet is available.
781 */
51470298 782static int ssh1_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
fb09bf1c 783{
51470298 784 struct rdpkt1_state_tag *st = &ssh->rdpkt1_state;
374330e2 785
51470298 786 crBegin(ssh->ssh1_rdpkt_crstate);
374330e2 787
32874aea 788 next_packet:
37508af4 789
51470298 790 ssh->pktin.type = 0;
791 ssh->pktin.length = 0;
374330e2 792
57476f6b 793 for (st->i = st->len = 0; st->i < 4; st->i++) {
fb09bf1c 794 while ((*datalen) == 0)
32874aea 795 crReturn(4 - st->i);
57476f6b 796 st->len = (st->len << 8) + **data;
fb09bf1c 797 (*data)++, (*datalen)--;
798 }
374330e2 799
57476f6b 800 st->pad = 8 - (st->len % 8);
801 st->biglen = st->len + st->pad;
51470298 802 ssh->pktin.length = st->len - 5;
fb09bf1c 803
51470298 804 if (ssh->pktin.maxlen < st->biglen) {
805 ssh->pktin.maxlen = st->biglen;
806 ssh->pktin.data = srealloc(ssh->pktin.data, st->biglen + APIEXTRA);
fb09bf1c 807 }
374330e2 808
57476f6b 809 st->to_read = st->biglen;
51470298 810 st->p = ssh->pktin.data;
57476f6b 811 while (st->to_read > 0) {
32874aea 812 st->chunk = st->to_read;
fb09bf1c 813 while ((*datalen) == 0)
57476f6b 814 crReturn(st->to_read);
815 if (st->chunk > (*datalen))
816 st->chunk = (*datalen);
817 memcpy(st->p, *data, st->chunk);
818 *data += st->chunk;
819 *datalen -= st->chunk;
820 st->p += st->chunk;
821 st->to_read -= st->chunk;
fb09bf1c 822 }
374330e2 823
0183b242 824 if (ssh->cipher && detect_attack(ssh->crcda_ctx, ssh->pktin.data,
825 st->biglen, NULL)) {
a8327734 826 bombout((ssh,"Network attack (CRC compensation) detected!"));
9a3a93a5 827 crReturn(0);
828 }
829
51470298 830 if (ssh->cipher)
371e569c 831 ssh->cipher->decrypt(ssh->v1_cipher_ctx, ssh->pktin.data, st->biglen);
374330e2 832
51470298 833 st->realcrc = crc32(ssh->pktin.data, st->biglen - 4);
834 st->gotcrc = GET_32BIT(ssh->pktin.data + st->biglen - 4);
57476f6b 835 if (st->gotcrc != st->realcrc) {
2dadaea5 836 bombout((ssh,"Incorrect CRC received on packet"));
32874aea 837 crReturn(0);
fb09bf1c 838 }
572f871e 839
51470298 840 ssh->pktin.body = ssh->pktin.data + st->pad + 1;
4ba9b64b 841
51470298 842 if (ssh->v1_compressing) {
4ba9b64b 843 unsigned char *decompblk;
844 int decomplen;
5366aed8 845 zlib_decompress_block(ssh->sc_comp_ctx,
846 ssh->pktin.body - 1, ssh->pktin.length + 1,
4ba9b64b 847 &decompblk, &decomplen);
848
51470298 849 if (ssh->pktin.maxlen < st->pad + decomplen) {
850 ssh->pktin.maxlen = st->pad + decomplen;
851 ssh->pktin.data = srealloc(ssh->pktin.data,
852 ssh->pktin.maxlen + APIEXTRA);
853 ssh->pktin.body = ssh->pktin.data + st->pad + 1;
4ba9b64b 854 }
855
51470298 856 memcpy(ssh->pktin.body - 1, decompblk, decomplen);
dcbde236 857 sfree(decompblk);
51470298 858 ssh->pktin.length = decomplen - 1;
4ba9b64b 859 }
860
51470298 861 ssh->pktin.type = ssh->pktin.body[-1];
00db133f 862
a8327734 863 if (ssh->logctx)
864 log_packet(ssh->logctx,
865 PKT_INCOMING, ssh->pktin.type,
866 ssh1_pkt_type(ssh->pktin.type),
867 ssh->pktin.body, ssh->pktin.length);
00db133f 868
51470298 869 if (ssh->pktin.type == SSH1_SMSG_STDOUT_DATA ||
870 ssh->pktin.type == SSH1_SMSG_STDERR_DATA ||
871 ssh->pktin.type == SSH1_MSG_DEBUG ||
872 ssh->pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE ||
873 ssh->pktin.type == SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
874 long stringlen = GET_32BIT(ssh->pktin.body);
875 if (stringlen + 4 != ssh->pktin.length) {
a8327734 876 bombout((ssh,"Received data packet with bogus string length"));
32874aea 877 crReturn(0);
878 }
fb09bf1c 879 }
880
51470298 881 if (ssh->pktin.type == SSH1_MSG_DEBUG) {
fb09bf1c 882 /* log debug message */
eb4504cc 883 char buf[512];
51470298 884 int stringlen = GET_32BIT(ssh->pktin.body);
eb4504cc 885 strcpy(buf, "Remote debug message: ");
886 if (stringlen > 480)
887 stringlen = 480;
51470298 888 memcpy(buf + 8, ssh->pktin.body + 4, stringlen);
3d63ca2e 889 buf[8 + stringlen] = '\0';
fb09bf1c 890 logevent(buf);
891 goto next_packet;
51470298 892 } else if (ssh->pktin.type == SSH1_MSG_IGNORE) {
fb09bf1c 893 /* do nothing */
894 goto next_packet;
895 }
896
51470298 897 if (ssh->pktin.type == SSH1_MSG_DISCONNECT) {
38c4a8da 898 /* log reason code in disconnect message */
899 char buf[256];
51470298 900 unsigned msglen = GET_32BIT(ssh->pktin.body);
260f3dec 901 unsigned nowlen;
38c4a8da 902 strcpy(buf, "Remote sent disconnect: ");
903 nowlen = strlen(buf);
32874aea 904 if (msglen > sizeof(buf) - nowlen - 1)
905 msglen = sizeof(buf) - nowlen - 1;
51470298 906 memcpy(buf + nowlen, ssh->pktin.body + 4, msglen);
32874aea 907 buf[nowlen + msglen] = '\0';
247308b5 908 /* logevent(buf); (this is now done within the bombout macro) */
a8327734 909 bombout((ssh,"Server sent disconnect message:\n\"%s\"", buf+nowlen));
e14d0f19 910 crReturn(0);
38c4a8da 911 }
912
fb09bf1c 913 crFinish(0);
914}
915
51470298 916static int ssh2_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
e5574168 917{
51470298 918 struct rdpkt2_state_tag *st = &ssh->rdpkt2_state;
e5574168 919
51470298 920 crBegin(ssh->ssh2_rdpkt_crstate);
e5574168 921
32874aea 922 next_packet:
51470298 923 ssh->pktin.type = 0;
924 ssh->pktin.length = 0;
925 if (ssh->sccipher)
926 st->cipherblk = ssh->sccipher->blksize;
e5574168 927 else
32874aea 928 st->cipherblk = 8;
960e736a 929 if (st->cipherblk < 8)
32874aea 930 st->cipherblk = 8;
960e736a 931
51470298 932 if (ssh->pktin.maxlen < st->cipherblk) {
933 ssh->pktin.maxlen = st->cipherblk;
934 ssh->pktin.data = srealloc(ssh->pktin.data, st->cipherblk + APIEXTRA);
e5574168 935 }
936
937 /*
938 * Acquire and decrypt the first block of the packet. This will
939 * contain the length and padding details.
940 */
32874aea 941 for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) {
e5574168 942 while ((*datalen) == 0)
32874aea 943 crReturn(st->cipherblk - st->i);
51470298 944 ssh->pktin.data[st->i] = *(*data)++;
32874aea 945 (*datalen)--;
e5574168 946 }
4252c9cc 947
51470298 948 if (ssh->sccipher)
371e569c 949 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
950 ssh->pktin.data, st->cipherblk);
e5574168 951
952 /*
953 * Now get the length and padding figures.
954 */
51470298 955 st->len = GET_32BIT(ssh->pktin.data);
956 st->pad = ssh->pktin.data[4];
e5574168 957
958 /*
717dc483 959 * _Completely_ silly lengths should be stomped on before they
960 * do us any more damage.
961 */
962 if (st->len < 0 || st->pad < 0 || st->len + st->pad < 0) {
a8327734 963 bombout((ssh,"Incoming packet was garbled on decryption"));
717dc483 964 crReturn(0);
965 }
966
967 /*
e5574168 968 * This enables us to deduce the payload length.
969 */
960e736a 970 st->payload = st->len - st->pad - 1;
e5574168 971
51470298 972 ssh->pktin.length = st->payload + 5;
e5574168 973
974 /*
975 * So now we can work out the total packet length.
976 */
960e736a 977 st->packetlen = st->len + 4;
51470298 978 st->maclen = ssh->scmac ? ssh->scmac->len : 0;
e5574168 979
980 /*
981 * Adjust memory allocation if packet is too big.
982 */
51470298 983 if (ssh->pktin.maxlen < st->packetlen + st->maclen) {
984 ssh->pktin.maxlen = st->packetlen + st->maclen;
985 ssh->pktin.data = srealloc(ssh->pktin.data,
986 ssh->pktin.maxlen + APIEXTRA);
e5574168 987 }
988
989 /*
990 * Read and decrypt the remainder of the packet.
991 */
32874aea 992 for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen;
993 st->i++) {
e5574168 994 while ((*datalen) == 0)
960e736a 995 crReturn(st->packetlen + st->maclen - st->i);
51470298 996 ssh->pktin.data[st->i] = *(*data)++;
32874aea 997 (*datalen)--;
e5574168 998 }
999 /* Decrypt everything _except_ the MAC. */
51470298 1000 if (ssh->sccipher)
371e569c 1001 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
1002 ssh->pktin.data + st->cipherblk,
51470298 1003 st->packetlen - st->cipherblk);
e5574168 1004
1005 /*
1006 * Check the MAC.
1007 */
51470298 1008 if (ssh->scmac
e0e1a00d 1009 && !ssh->scmac->verify(ssh->sc_mac_ctx, ssh->pktin.data, st->len + 4,
51470298 1010 st->incoming_sequence)) {
a8327734 1011 bombout((ssh,"Incorrect MAC received on packet"));
32874aea 1012 crReturn(0);
8d5de777 1013 }
32874aea 1014 st->incoming_sequence++; /* whether or not we MACed */
e5574168 1015
4ba9b64b 1016 /*
1017 * Decompress packet payload.
1018 */
1019 {
1020 unsigned char *newpayload;
1021 int newlen;
51470298 1022 if (ssh->sccomp &&
5366aed8 1023 ssh->sccomp->decompress(ssh->sc_comp_ctx,
1024 ssh->pktin.data + 5, ssh->pktin.length - 5,
51470298 1025 &newpayload, &newlen)) {
1026 if (ssh->pktin.maxlen < newlen + 5) {
1027 ssh->pktin.maxlen = newlen + 5;
1028 ssh->pktin.data = srealloc(ssh->pktin.data,
1029 ssh->pktin.maxlen + APIEXTRA);
4ba9b64b 1030 }
51470298 1031 ssh->pktin.length = 5 + newlen;
1032 memcpy(ssh->pktin.data + 5, newpayload, newlen);
dcbde236 1033 sfree(newpayload);
4ba9b64b 1034 }
1035 }
1036
51470298 1037 ssh->pktin.savedpos = 6;
1038 ssh->pktin.type = ssh->pktin.data[5];
e5574168 1039
a8327734 1040 if (ssh->logctx)
1041 log_packet(ssh->logctx, PKT_INCOMING, ssh->pktin.type,
1042 ssh2_pkt_type(ssh->pkt_ctx, ssh->pktin.type),
1043 ssh->pktin.data+6, ssh->pktin.length-6);
00db133f 1044
51470298 1045 switch (ssh->pktin.type) {
3d63ca2e 1046 /*
1047 * These packets we must handle instantly.
1048 */
1049 case SSH2_MSG_DISCONNECT:
1050 {
1051 /* log reason code in disconnect message */
57356d63 1052 char *buf;
1053 int nowlen;
51470298 1054 int reason = GET_32BIT(ssh->pktin.data + 6);
1055 unsigned msglen = GET_32BIT(ssh->pktin.data + 10);
57356d63 1056
3d63ca2e 1057 if (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) {
57356d63 1058 buf = dupprintf("Received disconnect message (%s)",
1059 ssh2_disconnect_reasons[reason]);
3d63ca2e 1060 } else {
57356d63 1061 buf = dupprintf("Received disconnect message (unknown"
1062 " type %d)", reason);
3d63ca2e 1063 }
1064 logevent(buf);
57356d63 1065 sfree(buf);
1066 buf = dupprintf("Disconnection message text: %n%.*s",
33b82b22 1067 &nowlen, msglen, ssh->pktin.data + 14);
3d63ca2e 1068 logevent(buf);
a8327734 1069 bombout((ssh,"Server sent disconnect message\ntype %d (%s):\n\"%s\"",
3d63ca2e 1070 reason,
1071 (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) ?
1072 ssh2_disconnect_reasons[reason] : "unknown",
1073 buf+nowlen));
57356d63 1074 sfree(buf);
3d63ca2e 1075 crReturn(0);
1076 }
1077 break;
1078 case SSH2_MSG_IGNORE:
1079 goto next_packet;
1080 case SSH2_MSG_DEBUG:
1081 {
1082 /* log the debug message */
1083 char buf[512];
51470298 1084 /* int display = ssh->pktin.body[6]; */
1085 int stringlen = GET_32BIT(ssh->pktin.data+7);
3d63ca2e 1086 int prefix;
1087 strcpy(buf, "Remote debug message: ");
1088 prefix = strlen(buf);
51470298 1089 if (stringlen > (int)(sizeof(buf)-prefix-1))
3d63ca2e 1090 stringlen = sizeof(buf)-prefix-1;
51470298 1091 memcpy(buf + prefix, ssh->pktin.data + 11, stringlen);
3d63ca2e 1092 buf[prefix + stringlen] = '\0';
1093 logevent(buf);
38c4a8da 1094 }
3d63ca2e 1095 goto next_packet; /* FIXME: print the debug message */
1096
1097 /*
1098 * These packets we need do nothing about here.
1099 */
1100 case SSH2_MSG_UNIMPLEMENTED:
1101 case SSH2_MSG_SERVICE_REQUEST:
1102 case SSH2_MSG_SERVICE_ACCEPT:
1103 case SSH2_MSG_KEXINIT:
1104 case SSH2_MSG_NEWKEYS:
1105 case SSH2_MSG_KEXDH_INIT:
1106 case SSH2_MSG_KEXDH_REPLY:
1107 /* case SSH2_MSG_KEX_DH_GEX_REQUEST: duplicate case value */
1108 /* case SSH2_MSG_KEX_DH_GEX_GROUP: duplicate case value */
1109 case SSH2_MSG_KEX_DH_GEX_INIT:
1110 case SSH2_MSG_KEX_DH_GEX_REPLY:
1111 case SSH2_MSG_USERAUTH_REQUEST:
1112 case SSH2_MSG_USERAUTH_FAILURE:
1113 case SSH2_MSG_USERAUTH_SUCCESS:
1114 case SSH2_MSG_USERAUTH_BANNER:
1115 case SSH2_MSG_USERAUTH_PK_OK:
1116 /* case SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: duplicate case value */
1117 /* case SSH2_MSG_USERAUTH_INFO_REQUEST: duplicate case value */
1118 case SSH2_MSG_USERAUTH_INFO_RESPONSE:
1119 case SSH2_MSG_GLOBAL_REQUEST:
1120 case SSH2_MSG_REQUEST_SUCCESS:
1121 case SSH2_MSG_REQUEST_FAILURE:
1122 case SSH2_MSG_CHANNEL_OPEN:
1123 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
1124 case SSH2_MSG_CHANNEL_OPEN_FAILURE:
1125 case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
1126 case SSH2_MSG_CHANNEL_DATA:
1127 case SSH2_MSG_CHANNEL_EXTENDED_DATA:
1128 case SSH2_MSG_CHANNEL_EOF:
1129 case SSH2_MSG_CHANNEL_CLOSE:
1130 case SSH2_MSG_CHANNEL_REQUEST:
1131 case SSH2_MSG_CHANNEL_SUCCESS:
1132 case SSH2_MSG_CHANNEL_FAILURE:
1133 break;
1134
1135 /*
1136 * For anything else we send SSH2_MSG_UNIMPLEMENTED.
1137 */
1138 default:
51470298 1139 ssh2_pkt_init(ssh, SSH2_MSG_UNIMPLEMENTED);
1140 ssh2_pkt_adduint32(ssh, st->incoming_sequence - 1);
1141 ssh2_pkt_send(ssh);
3d63ca2e 1142 break;
38c4a8da 1143 }
1144
e5574168 1145 crFinish(0);
1146}
1147
51470298 1148static void ssh1_pktout_size(Ssh ssh, int len)
32874aea 1149{
374330e2 1150 int pad, biglen;
1151
1152 len += 5; /* type and CRC */
32874aea 1153 pad = 8 - (len % 8);
374330e2 1154 biglen = len + pad;
1155
51470298 1156 ssh->pktout.length = len - 5;
1157 if (ssh->pktout.maxlen < biglen) {
1158 ssh->pktout.maxlen = biglen;
8f203108 1159#ifdef MSCRYPTOAPI
fb09bf1c 1160 /* Allocate enough buffer space for extra block
8f203108 1161 * for MS CryptEncrypt() */
51470298 1162 ssh->pktout.data = srealloc(ssh->pktout.data, biglen + 12);
8f203108 1163#else
51470298 1164 ssh->pktout.data = srealloc(ssh->pktout.data, biglen + 4);
8f203108 1165#endif
374330e2 1166 }
51470298 1167 ssh->pktout.body = ssh->pktout.data + 4 + pad + 1;
4ba9b64b 1168}
374330e2 1169
51470298 1170static void s_wrpkt_start(Ssh ssh, int type, int len)
32874aea 1171{
51470298 1172 ssh1_pktout_size(ssh, len);
1173 ssh->pktout.type = type;
374330e2 1174}
1175
51470298 1176static int s_wrpkt_prepare(Ssh ssh)
32874aea 1177{
fd7a4aad 1178 int pad, biglen, i;
374330e2 1179 unsigned long crc;
fd7a4aad 1180#ifdef __SC__
1181 /*
1182 * XXX various versions of SC (including 8.8.4) screw up the
1183 * register allocation in this function and use the same register
1184 * (D6) for len and as a temporary, with predictable results. The
1185 * following sledgehammer prevents this.
1186 */
1187 volatile
1188#endif
1189 int len;
374330e2 1190
51470298 1191 ssh->pktout.body[-1] = ssh->pktout.type;
4ba9b64b 1192
a8327734 1193 if (ssh->logctx)
1194 log_packet(ssh->logctx, PKT_OUTGOING, ssh->pktout.type,
1195 ssh1_pkt_type(ssh->pktout.type),
1196 ssh->pktout.body, ssh->pktout.length);
00db133f 1197
51470298 1198 if (ssh->v1_compressing) {
4ba9b64b 1199 unsigned char *compblk;
1200 int complen;
5366aed8 1201 zlib_compress_block(ssh->cs_comp_ctx,
1202 ssh->pktout.body - 1, ssh->pktout.length + 1,
4ba9b64b 1203 &compblk, &complen);
51470298 1204 ssh1_pktout_size(ssh, complen - 1);
1205 memcpy(ssh->pktout.body - 1, compblk, complen);
dcbde236 1206 sfree(compblk);
4ba9b64b 1207 }
1208
51470298 1209 len = ssh->pktout.length + 5; /* type and CRC */
32874aea 1210 pad = 8 - (len % 8);
374330e2 1211 biglen = len + pad;
1212
32874aea 1213 for (i = 0; i < pad; i++)
51470298 1214 ssh->pktout.data[i + 4] = random_byte();
1215 crc = crc32(ssh->pktout.data + 4, biglen - 4);
1216 PUT_32BIT(ssh->pktout.data + biglen, crc);
1217 PUT_32BIT(ssh->pktout.data, len);
374330e2 1218
51470298 1219 if (ssh->cipher)
371e569c 1220 ssh->cipher->encrypt(ssh->v1_cipher_ctx, ssh->pktout.data + 4, biglen);
374330e2 1221
32874aea 1222 return biglen + 4;
39065bed 1223}
1224
51470298 1225static void s_wrpkt(Ssh ssh)
32874aea 1226{
5471d09a 1227 int len, backlog;
51470298 1228 len = s_wrpkt_prepare(ssh);
d8baa528 1229 backlog = sk_write(ssh->s, (char *)ssh->pktout.data, len);
5471d09a 1230 if (backlog > SSH_MAX_BACKLOG)
51470298 1231 ssh_throttle_all(ssh, 1, backlog);
39065bed 1232}
1233
51470298 1234static void s_wrpkt_defer(Ssh ssh)
32874aea 1235{
39065bed 1236 int len;
51470298 1237 len = s_wrpkt_prepare(ssh);
1238 if (ssh->deferred_len + len > ssh->deferred_size) {
1239 ssh->deferred_size = ssh->deferred_len + len + 128;
1240 ssh->deferred_send_data = srealloc(ssh->deferred_send_data,
1241 ssh->deferred_size);
39065bed 1242 }
51470298 1243 memcpy(ssh->deferred_send_data + ssh->deferred_len, ssh->pktout.data, len);
1244 ssh->deferred_len += len;
374330e2 1245}
1246
fb09bf1c 1247/*
39065bed 1248 * Construct a packet with the specified contents.
fb09bf1c 1249 */
51470298 1250static void construct_packet(Ssh ssh, int pkttype, va_list ap1, va_list ap2)
fb09bf1c 1251{
fb09bf1c 1252 unsigned char *p, *argp, argchar;
1253 unsigned long argint;
1254 int pktlen, argtype, arglen;
7cca0d81 1255 Bignum bn;
fb09bf1c 1256
1257 pktlen = 0;
39065bed 1258 while ((argtype = va_arg(ap1, int)) != PKT_END) {
fb09bf1c 1259 switch (argtype) {
1260 case PKT_INT:
39065bed 1261 (void) va_arg(ap1, int);
fb09bf1c 1262 pktlen += 4;
1263 break;
1264 case PKT_CHAR:
1ec39246 1265 (void) va_arg(ap1, int);
fb09bf1c 1266 pktlen++;
1267 break;
1268 case PKT_DATA:
39065bed 1269 (void) va_arg(ap1, unsigned char *);
1270 arglen = va_arg(ap1, int);
fb09bf1c 1271 pktlen += arglen;
1272 break;
1273 case PKT_STR:
39065bed 1274 argp = va_arg(ap1, unsigned char *);
d8baa528 1275 arglen = strlen((char *)argp);
fb09bf1c 1276 pktlen += 4 + arglen;
1277 break;
7cca0d81 1278 case PKT_BIGNUM:
39065bed 1279 bn = va_arg(ap1, Bignum);
32874aea 1280 pktlen += ssh1_bignum_length(bn);
7cca0d81 1281 break;
fb09bf1c 1282 default:
1283 assert(0);
1284 }
1285 }
fb09bf1c 1286
51470298 1287 s_wrpkt_start(ssh, pkttype, pktlen);
1288 p = ssh->pktout.body;
fb09bf1c 1289
39065bed 1290 while ((argtype = va_arg(ap2, int)) != PKT_END) {
fb09bf1c 1291 switch (argtype) {
1292 case PKT_INT:
39065bed 1293 argint = va_arg(ap2, int);
fb09bf1c 1294 PUT_32BIT(p, argint);
1295 p += 4;
1296 break;
1297 case PKT_CHAR:
1ec39246 1298 argchar = (unsigned char) va_arg(ap2, int);
fb09bf1c 1299 *p = argchar;
1300 p++;
1301 break;
1302 case PKT_DATA:
39065bed 1303 argp = va_arg(ap2, unsigned char *);
1304 arglen = va_arg(ap2, int);
fb09bf1c 1305 memcpy(p, argp, arglen);
1306 p += arglen;
1307 break;
1308 case PKT_STR:
39065bed 1309 argp = va_arg(ap2, unsigned char *);
d8baa528 1310 arglen = strlen((char *)argp);
fb09bf1c 1311 PUT_32BIT(p, arglen);
1312 memcpy(p + 4, argp, arglen);
1313 p += 4 + arglen;
1314 break;
7cca0d81 1315 case PKT_BIGNUM:
39065bed 1316 bn = va_arg(ap2, Bignum);
32874aea 1317 p += ssh1_write_bignum(p, bn);
7cca0d81 1318 break;
fb09bf1c 1319 }
1320 }
39065bed 1321}
fb09bf1c 1322
51470298 1323static void send_packet(Ssh ssh, int pkttype, ...)
32874aea 1324{
39065bed 1325 va_list ap1, ap2;
1326 va_start(ap1, pkttype);
1327 va_start(ap2, pkttype);
51470298 1328 construct_packet(ssh, pkttype, ap1, ap2);
1329 s_wrpkt(ssh);
fb09bf1c 1330}
1331
51470298 1332static void defer_packet(Ssh ssh, int pkttype, ...)
32874aea 1333{
39065bed 1334 va_list ap1, ap2;
1335 va_start(ap1, pkttype);
1336 va_start(ap2, pkttype);
51470298 1337 construct_packet(ssh, pkttype, ap1, ap2);
1338 s_wrpkt_defer(ssh);
39065bed 1339}
1340
32874aea 1341static int ssh_versioncmp(char *a, char *b)
1342{
9697bfd2 1343 char *ae, *be;
1344 unsigned long av, bv;
1345
43aa02a7 1346 av = strtoul(a, &ae, 10);
1347 bv = strtoul(b, &be, 10);
32874aea 1348 if (av != bv)
1349 return (av < bv ? -1 : +1);
1350 if (*ae == '.')
1351 ae++;
1352 if (*be == '.')
1353 be++;
43aa02a7 1354 av = strtoul(ae, &ae, 10);
1355 bv = strtoul(be, &be, 10);
32874aea 1356 if (av != bv)
1357 return (av < bv ? -1 : +1);
9697bfd2 1358 return 0;
1359}
1360
e5574168 1361/*
a92dd380 1362 * Utility routines for putting an SSH-protocol `string' and
1363 * `uint32' into a SHA state.
e5574168 1364 */
1365#include <stdio.h>
32874aea 1366static void sha_string(SHA_State * s, void *str, int len)
1367{
e5574168 1368 unsigned char lenblk[4];
e5574168 1369 PUT_32BIT(lenblk, len);
e5574168 1370 SHA_Bytes(s, lenblk, 4);
e5574168 1371 SHA_Bytes(s, str, len);
1372}
1373
32874aea 1374static void sha_uint32(SHA_State * s, unsigned i)
1375{
a92dd380 1376 unsigned char intblk[4];
1377 PUT_32BIT(intblk, i);
1378 SHA_Bytes(s, intblk, 4);
1379}
1380
7cca0d81 1381/*
1382 * SSH2 packet construction functions.
1383 */
51470298 1384static void ssh2_pkt_ensure(Ssh ssh, int length)
32874aea 1385{
51470298 1386 if (ssh->pktout.maxlen < length) {
1387 ssh->pktout.maxlen = length + 256;
1388 ssh->pktout.data = srealloc(ssh->pktout.data,
1389 ssh->pktout.maxlen + APIEXTRA);
1390 if (!ssh->pktout.data)
32874aea 1391 fatalbox("Out of memory");
7cca0d81 1392 }
783415f8 1393}
51470298 1394static void ssh2_pkt_adddata(Ssh ssh, void *data, int len)
32874aea 1395{
51470298 1396 ssh->pktout.length += len;
1397 ssh2_pkt_ensure(ssh, ssh->pktout.length);
1398 memcpy(ssh->pktout.data + ssh->pktout.length - len, data, len);
7cca0d81 1399}
51470298 1400static void ssh2_pkt_addbyte(Ssh ssh, unsigned char byte)
32874aea 1401{
51470298 1402 ssh2_pkt_adddata(ssh, &byte, 1);
7cca0d81 1403}
51470298 1404static void ssh2_pkt_init(Ssh ssh, int pkt_type)
32874aea 1405{
51470298 1406 ssh->pktout.length = 5;
1407 ssh2_pkt_addbyte(ssh, (unsigned char) pkt_type);
7cca0d81 1408}
51470298 1409static void ssh2_pkt_addbool(Ssh ssh, unsigned char value)
32874aea 1410{
51470298 1411 ssh2_pkt_adddata(ssh, &value, 1);
7cca0d81 1412}
51470298 1413static void ssh2_pkt_adduint32(Ssh ssh, unsigned long value)
32874aea 1414{
7cca0d81 1415 unsigned char x[4];
1416 PUT_32BIT(x, value);
51470298 1417 ssh2_pkt_adddata(ssh, x, 4);
7cca0d81 1418}
51470298 1419static void ssh2_pkt_addstring_start(Ssh ssh)
32874aea 1420{
51470298 1421 ssh2_pkt_adduint32(ssh, 0);
1422 ssh->pktout.savedpos = ssh->pktout.length;
7cca0d81 1423}
51470298 1424static void ssh2_pkt_addstring_str(Ssh ssh, char *data)
32874aea 1425{
51470298 1426 ssh2_pkt_adddata(ssh, data, strlen(data));
1427 PUT_32BIT(ssh->pktout.data + ssh->pktout.savedpos - 4,
1428 ssh->pktout.length - ssh->pktout.savedpos);
7cca0d81 1429}
51470298 1430static void ssh2_pkt_addstring_data(Ssh ssh, char *data, int len)
32874aea 1431{
51470298 1432 ssh2_pkt_adddata(ssh, data, len);
1433 PUT_32BIT(ssh->pktout.data + ssh->pktout.savedpos - 4,
1434 ssh->pktout.length - ssh->pktout.savedpos);
7cca0d81 1435}
51470298 1436static void ssh2_pkt_addstring(Ssh ssh, char *data)
32874aea 1437{
51470298 1438 ssh2_pkt_addstring_start(ssh);
1439 ssh2_pkt_addstring_str(ssh, data);
7cca0d81 1440}
d8baa528 1441static unsigned char *ssh2_mpint_fmt(Bignum b, int *len)
32874aea 1442{
7cca0d81 1443 unsigned char *p;
32874aea 1444 int i, n = (bignum_bitcount(b) + 7) / 8;
3709bfe9 1445 p = smalloc(n + 1);
7cca0d81 1446 if (!p)
32874aea 1447 fatalbox("out of memory");
7cca0d81 1448 p[0] = 0;
3709bfe9 1449 for (i = 1; i <= n; i++)
32874aea 1450 p[i] = bignum_byte(b, n - i);
7cca0d81 1451 i = 0;
32874aea 1452 while (i <= n && p[i] == 0 && (p[i + 1] & 0x80) == 0)
1453 i++;
1454 memmove(p, p + i, n + 1 - i);
1455 *len = n + 1 - i;
7cca0d81 1456 return p;
1457}
51470298 1458static void ssh2_pkt_addmp(Ssh ssh, Bignum b)
32874aea 1459{
7cca0d81 1460 unsigned char *p;
1461 int len;
1462 p = ssh2_mpint_fmt(b, &len);
51470298 1463 ssh2_pkt_addstring_start(ssh);
d8baa528 1464 ssh2_pkt_addstring_data(ssh, (char *)p, len);
dcbde236 1465 sfree(p);
7cca0d81 1466}
b185170a 1467
1468/*
1469 * Construct an SSH2 final-form packet: compress it, encrypt it,
1470 * put the MAC on it. Final packet, ready to be sent, is stored in
51470298 1471 * ssh->pktout.data. Total length is returned.
b185170a 1472 */
51470298 1473static int ssh2_pkt_construct(Ssh ssh)
32874aea 1474{
7cca0d81 1475 int cipherblk, maclen, padding, i;
7cca0d81 1476
a8327734 1477 if (ssh->logctx)
1478 log_packet(ssh->logctx, PKT_OUTGOING, ssh->pktout.data[5],
1479 ssh2_pkt_type(ssh->pkt_ctx, ssh->pktout.data[5]),
1480 ssh->pktout.data + 6, ssh->pktout.length - 6);
00db133f 1481
7cca0d81 1482 /*
4ba9b64b 1483 * Compress packet payload.
1484 */
4ba9b64b 1485 {
1486 unsigned char *newpayload;
1487 int newlen;
51470298 1488 if (ssh->cscomp &&
5366aed8 1489 ssh->cscomp->compress(ssh->cs_comp_ctx, ssh->pktout.data + 5,
1490 ssh->pktout.length - 5,
51470298 1491 &newpayload, &newlen)) {
1492 ssh->pktout.length = 5;
1493 ssh2_pkt_adddata(ssh, newpayload, newlen);
dcbde236 1494 sfree(newpayload);
4ba9b64b 1495 }
1496 }
1497
1498 /*
7cca0d81 1499 * Add padding. At least four bytes, and must also bring total
1500 * length (minus MAC) up to a multiple of the block size.
1501 */
51470298 1502 cipherblk = ssh->cscipher ? ssh->cscipher->blksize : 8; /* block size */
32874aea 1503 cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
7cca0d81 1504 padding = 4;
32874aea 1505 padding +=
51470298 1506 (cipherblk - (ssh->pktout.length + padding) % cipherblk) % cipherblk;
1507 maclen = ssh->csmac ? ssh->csmac->len : 0;
1508 ssh2_pkt_ensure(ssh, ssh->pktout.length + padding + maclen);
1509 ssh->pktout.data[4] = padding;
7cca0d81 1510 for (i = 0; i < padding; i++)
51470298 1511 ssh->pktout.data[ssh->pktout.length + i] = random_byte();
1512 PUT_32BIT(ssh->pktout.data, ssh->pktout.length + padding - 4);
1513 if (ssh->csmac)
e0e1a00d 1514 ssh->csmac->generate(ssh->cs_mac_ctx, ssh->pktout.data,
1515 ssh->pktout.length + padding,
51470298 1516 ssh->v2_outgoing_sequence);
1517 ssh->v2_outgoing_sequence++; /* whether or not we MACed */
1518
1519 if (ssh->cscipher)
371e569c 1520 ssh->cscipher->encrypt(ssh->cs_cipher_ctx,
1521 ssh->pktout.data, ssh->pktout.length + padding);
51470298 1522
1523 /* Ready-to-send packet starts at ssh->pktout.data. We return length. */
1524 return ssh->pktout.length + padding + maclen;
b185170a 1525}
1526
1527/*
1528 * Construct and send an SSH2 packet immediately.
1529 */
51470298 1530static void ssh2_pkt_send(Ssh ssh)
32874aea 1531{
5471d09a 1532 int len;
1533 int backlog;
51470298 1534 len = ssh2_pkt_construct(ssh);
d8baa528 1535 backlog = sk_write(ssh->s, (char *)ssh->pktout.data, len);
5471d09a 1536 if (backlog > SSH_MAX_BACKLOG)
51470298 1537 ssh_throttle_all(ssh, 1, backlog);
b185170a 1538}
1539
1540/*
1541 * Construct an SSH2 packet and add it to a deferred data block.
1542 * Useful for sending multiple packets in a single sk_write() call,
1543 * to prevent a traffic-analysing listener from being able to work
1544 * out the length of any particular packet (such as the password
1545 * packet).
1546 *
1547 * Note that because SSH2 sequence-numbers its packets, this can
1548 * NOT be used as an m4-style `defer' allowing packets to be
1549 * constructed in one order and sent in another.
1550 */
51470298 1551static void ssh2_pkt_defer(Ssh ssh)
32874aea 1552{
51470298 1553 int len = ssh2_pkt_construct(ssh);
1554 if (ssh->deferred_len + len > ssh->deferred_size) {
1555 ssh->deferred_size = ssh->deferred_len + len + 128;
1556 ssh->deferred_send_data = srealloc(ssh->deferred_send_data,
1557 ssh->deferred_size);
b185170a 1558 }
51470298 1559 memcpy(ssh->deferred_send_data + ssh->deferred_len, ssh->pktout.data, len);
1560 ssh->deferred_len += len;
b185170a 1561}
1562
1563/*
1564 * Send the whole deferred data block constructed by
39065bed 1565 * ssh2_pkt_defer() or SSH1's defer_packet().
b185170a 1566 */
51470298 1567static void ssh_pkt_defersend(Ssh ssh)
32874aea 1568{
5471d09a 1569 int backlog;
d8baa528 1570 backlog = sk_write(ssh->s, (char *)ssh->deferred_send_data,
1571 ssh->deferred_len);
51470298 1572 ssh->deferred_len = ssh->deferred_size = 0;
1573 sfree(ssh->deferred_send_data);
1574 ssh->deferred_send_data = NULL;
5471d09a 1575 if (backlog > SSH_MAX_BACKLOG)
51470298 1576 ssh_throttle_all(ssh, 1, backlog);
7cca0d81 1577}
1578
1579#if 0
32874aea 1580void bndebug(char *string, Bignum b)
1581{
7cca0d81 1582 unsigned char *p;
1583 int i, len;
1584 p = ssh2_mpint_fmt(b, &len);
1585 debug(("%s", string));
1586 for (i = 0; i < len; i++)
32874aea 1587 debug((" %02x", p[i]));
765c4200 1588 debug(("\n"));
dcbde236 1589 sfree(p);
7cca0d81 1590}
1591#endif
1592
32874aea 1593static void sha_mpint(SHA_State * s, Bignum b)
1594{
7cca0d81 1595 unsigned char *p;
1596 int len;
1597 p = ssh2_mpint_fmt(b, &len);
1598 sha_string(s, p, len);
dcbde236 1599 sfree(p);
7cca0d81 1600}
1601
1602/*
1603 * SSH2 packet decode functions.
1604 */
51470298 1605static unsigned long ssh2_pkt_getuint32(Ssh ssh)
32874aea 1606{
7cca0d81 1607 unsigned long value;
51470298 1608 if (ssh->pktin.length - ssh->pktin.savedpos < 4)
32874aea 1609 return 0; /* arrgh, no way to decline (FIXME?) */
51470298 1610 value = GET_32BIT(ssh->pktin.data + ssh->pktin.savedpos);
1611 ssh->pktin.savedpos += 4;
7cca0d81 1612 return value;
1613}
51470298 1614static int ssh2_pkt_getbool(Ssh ssh)
32874aea 1615{
65a22376 1616 unsigned long value;
51470298 1617 if (ssh->pktin.length - ssh->pktin.savedpos < 1)
32874aea 1618 return 0; /* arrgh, no way to decline (FIXME?) */
51470298 1619 value = ssh->pktin.data[ssh->pktin.savedpos] != 0;
1620 ssh->pktin.savedpos++;
65a22376 1621 return value;
1622}
51470298 1623static void ssh2_pkt_getstring(Ssh ssh, char **p, int *length)
32874aea 1624{
57356d63 1625 int len;
7cca0d81 1626 *p = NULL;
45068b27 1627 *length = 0;
51470298 1628 if (ssh->pktin.length - ssh->pktin.savedpos < 4)
32874aea 1629 return;
57356d63 1630 len = GET_32BIT(ssh->pktin.data + ssh->pktin.savedpos);
1631 if (len < 0)
1632 return;
1633 *length = len;
51470298 1634 ssh->pktin.savedpos += 4;
1635 if (ssh->pktin.length - ssh->pktin.savedpos < *length)
32874aea 1636 return;
d8baa528 1637 *p = (char *)(ssh->pktin.data + ssh->pktin.savedpos);
51470298 1638 ssh->pktin.savedpos += *length;
7cca0d81 1639}
51470298 1640static Bignum ssh2_pkt_getmp(Ssh ssh)
32874aea 1641{
7cca0d81 1642 char *p;
3709bfe9 1643 int length;
7cca0d81 1644 Bignum b;
1645
51470298 1646 ssh2_pkt_getstring(ssh, &p, &length);
7cca0d81 1647 if (!p)
32874aea 1648 return NULL;
8d5de777 1649 if (p[0] & 0x80) {
a8327734 1650 bombout((ssh,"internal error: Can't handle negative mpints"));
32874aea 1651 return NULL;
8d5de777 1652 }
d8baa528 1653 b = bignum_from_bytes((unsigned char *)p, length);
7cca0d81 1654 return b;
1655}
1656
7d503c31 1657/*
1dd353b5 1658 * Helper function to add an SSH2 signature blob to a packet.
1659 * Expects to be shown the public key blob as well as the signature
1660 * blob. Normally works just like ssh2_pkt_addstring, but will
1661 * fiddle with the signature packet if necessary for
1662 * BUG_SSH2_RSA_PADDING.
1663 */
51470298 1664static void ssh2_add_sigblob(Ssh ssh, void *pkblob_v, int pkblob_len,
1dd353b5 1665 void *sigblob_v, int sigblob_len)
1666{
1667 unsigned char *pkblob = (unsigned char *)pkblob_v;
1668 unsigned char *sigblob = (unsigned char *)sigblob_v;
1669
1670 /* dmemdump(pkblob, pkblob_len); */
1671 /* dmemdump(sigblob, sigblob_len); */
1672
1673 /*
1674 * See if this is in fact an ssh-rsa signature and a buggy
1675 * server; otherwise we can just do this the easy way.
1676 */
51470298 1677 if ((ssh->remote_bugs & BUG_SSH2_RSA_PADDING) &&
1dd353b5 1678 (GET_32BIT(pkblob) == 7 && !memcmp(pkblob+4, "ssh-rsa", 7))) {
1679 int pos, len, siglen;
1680
1681 /*
1682 * Find the byte length of the modulus.
1683 */
1684
1685 pos = 4+7; /* skip over "ssh-rsa" */
1686 pos += 4 + GET_32BIT(pkblob+pos); /* skip over exponent */
1687 len = GET_32BIT(pkblob+pos); /* find length of modulus */
1688 pos += 4; /* find modulus itself */
1689 while (len > 0 && pkblob[pos] == 0)
1690 len--, pos++;
1691 /* debug(("modulus length is %d\n", len)); */
1692
1693 /*
1694 * Now find the signature integer.
1695 */
1696 pos = 4+7; /* skip over "ssh-rsa" */
1697 siglen = GET_32BIT(sigblob+pos);
1698 /* debug(("signature length is %d\n", siglen)); */
1699
1700 if (len != siglen) {
1701 unsigned char newlen[4];
51470298 1702 ssh2_pkt_addstring_start(ssh);
d8baa528 1703 ssh2_pkt_addstring_data(ssh, (char *)sigblob, pos);
1dd353b5 1704 /* dmemdump(sigblob, pos); */
1705 pos += 4; /* point to start of actual sig */
1706 PUT_32BIT(newlen, len);
d8baa528 1707 ssh2_pkt_addstring_data(ssh, (char *)newlen, 4);
1dd353b5 1708 /* dmemdump(newlen, 4); */
1709 newlen[0] = 0;
1710 while (len-- > siglen) {
d8baa528 1711 ssh2_pkt_addstring_data(ssh, (char *)newlen, 1);
1dd353b5 1712 /* dmemdump(newlen, 1); */
1713 }
d8baa528 1714 ssh2_pkt_addstring_data(ssh, (char *)(sigblob+pos), siglen);
1dd353b5 1715 /* dmemdump(sigblob+pos, siglen); */
1716 return;
1717 }
1718
1719 /* Otherwise fall through and do it the easy way. */
1720 }
1721
51470298 1722 ssh2_pkt_addstring_start(ssh);
d8baa528 1723 ssh2_pkt_addstring_data(ssh, (char *)sigblob, sigblob_len);
1dd353b5 1724}
1725
1726/*
7d503c31 1727 * Examine the remote side's version string and compare it against
1728 * a list of known buggy implementations.
1729 */
51470298 1730static void ssh_detect_bugs(Ssh ssh, char *vstring)
32874aea 1731{
1732 char *imp; /* pointer to implementation part */
7d503c31 1733 imp = vstring;
1734 imp += strcspn(imp, "-");
bd358db1 1735 if (*imp) imp++;
7d503c31 1736 imp += strcspn(imp, "-");
bd358db1 1737 if (*imp) imp++;
7d503c31 1738
51470298 1739 ssh->remote_bugs = 0;
7d503c31 1740
5ecd7ad0 1741 if (ssh->cfg.sshbug_ignore1 == FORCE_ON ||
1742 (ssh->cfg.sshbug_ignore1 == AUTO &&
2c9c6388 1743 (!strcmp(imp, "1.2.18") || !strcmp(imp, "1.2.19") ||
1744 !strcmp(imp, "1.2.20") || !strcmp(imp, "1.2.21") ||
1745 !strcmp(imp, "1.2.22") || !strcmp(imp, "Cisco-1.25")))) {
32874aea 1746 /*
1747 * These versions don't support SSH1_MSG_IGNORE, so we have
1748 * to use a different defence against password length
1749 * sniffing.
1750 */
51470298 1751 ssh->remote_bugs |= BUG_CHOKES_ON_SSH1_IGNORE;
32874aea 1752 logevent("We believe remote version has SSH1 ignore bug");
7d503c31 1753 }
1754
5ecd7ad0 1755 if (ssh->cfg.sshbug_plainpw1 == FORCE_ON ||
1756 (ssh->cfg.sshbug_plainpw1 == AUTO &&
2c9c6388 1757 (!strcmp(imp, "Cisco-1.25")))) {
bd358db1 1758 /*
1759 * These versions need a plain password sent; they can't
1760 * handle having a null and a random length of data after
1761 * the password.
1762 */
51470298 1763 ssh->remote_bugs |= BUG_NEEDS_SSH1_PLAIN_PASSWORD;
bd358db1 1764 logevent("We believe remote version needs a plain SSH1 password");
1765 }
1766
5ecd7ad0 1767 if (ssh->cfg.sshbug_rsa1 == FORCE_ON ||
1768 (ssh->cfg.sshbug_rsa1 == AUTO &&
2c9c6388 1769 (!strcmp(imp, "Cisco-1.25")))) {
0df73905 1770 /*
1771 * These versions apparently have no clue whatever about
1772 * RSA authentication and will panic and die if they see
1773 * an AUTH_RSA message.
1774 */
51470298 1775 ssh->remote_bugs |= BUG_CHOKES_ON_RSA;
0df73905 1776 logevent("We believe remote version can't handle RSA authentication");
1777 }
1778
5ecd7ad0 1779 if (ssh->cfg.sshbug_hmac2 == FORCE_ON ||
1780 (ssh->cfg.sshbug_hmac2 == AUTO &&
831301f6 1781 (wc_match("2.1.0*", imp) || wc_match("2.0.*", imp) ||
1782 wc_match("2.2.0*", imp) || wc_match("2.3.0*", imp) ||
1783 wc_match("2.1 *", imp)))) {
32874aea 1784 /*
1785 * These versions have the HMAC bug.
1786 */
51470298 1787 ssh->remote_bugs |= BUG_SSH2_HMAC;
32874aea 1788 logevent("We believe remote version has SSH2 HMAC bug");
7d503c31 1789 }
1dd353b5 1790
5ecd7ad0 1791 if (ssh->cfg.sshbug_derivekey2 == FORCE_ON ||
1792 (ssh->cfg.sshbug_derivekey2 == AUTO &&
2856a1b9 1793 (wc_match("2.0.0*", imp) || wc_match("2.0.10*", imp) ))) {
088bde77 1794 /*
1795 * These versions have the key-derivation bug (failing to
1796 * include the literal shared secret in the hashes that
1797 * generate the keys).
1798 */
51470298 1799 ssh->remote_bugs |= BUG_SSH2_DERIVEKEY;
088bde77 1800 logevent("We believe remote version has SSH2 key-derivation bug");
1801 }
1802
5ecd7ad0 1803 if (ssh->cfg.sshbug_rsapad2 == FORCE_ON ||
1804 (ssh->cfg.sshbug_rsapad2 == AUTO &&
831301f6 1805 (wc_match("OpenSSH_2.[5-9]*", imp) ||
1806 wc_match("OpenSSH_3.[0-2]*", imp)))) {
1dd353b5 1807 /*
1808 * These versions have the SSH2 RSA padding bug.
1809 */
51470298 1810 ssh->remote_bugs |= BUG_SSH2_RSA_PADDING;
1dd353b5 1811 logevent("We believe remote version has SSH2 RSA padding bug");
1812 }
8e975795 1813
dda87a28 1814 if (ssh->cfg.sshbug_pksessid2 == FORCE_ON ||
1815 (ssh->cfg.sshbug_pksessid2 == AUTO &&
1816 wc_match("OpenSSH_2.[0-2]*", imp))) {
1817 /*
1818 * These versions have the SSH2 session-ID bug in
1819 * public-key authentication.
1820 */
1821 ssh->remote_bugs |= BUG_SSH2_PK_SESSIONID;
1822 logevent("We believe remote version has SSH2 public-key-session-ID bug");
1823 }
1824
5ecd7ad0 1825 if (ssh->cfg.sshbug_dhgex2 == FORCE_ON) {
8e975795 1826 /*
831301f6 1827 * User specified the SSH2 DH GEX bug.
8e975795 1828 */
51470298 1829 ssh->remote_bugs |= BUG_SSH2_DH_GEX;
8e975795 1830 logevent("We believe remote version has SSH2 DH group exchange bug");
1831 }
7d503c31 1832}
1833
51470298 1834static int do_ssh_init(Ssh ssh, unsigned char c)
32874aea 1835{
51470298 1836 struct do_ssh_init_state {
1837 int vslen;
1838 char version[10];
1839 char *vstring;
1840 int vstrsize;
1841 int i;
1842 int proto1, proto2;
1843 };
1844 crState(do_ssh_init_state);
374330e2 1845
51470298 1846 crBegin(ssh->do_ssh_init_crstate);
8df7a775 1847
1848 /* Search for the string "SSH-" in the input. */
51470298 1849 s->i = 0;
8df7a775 1850 while (1) {
1851 static const int transS[] = { 1, 2, 2, 1 };
1852 static const int transH[] = { 0, 0, 3, 0 };
1853 static const int transminus[] = { 0, 0, 0, -1 };
32874aea 1854 if (c == 'S')
51470298 1855 s->i = transS[s->i];
32874aea 1856 else if (c == 'H')
51470298 1857 s->i = transH[s->i];
32874aea 1858 else if (c == '-')
51470298 1859 s->i = transminus[s->i];
32874aea 1860 else
51470298 1861 s->i = 0;
1862 if (s->i < 0)
8df7a775 1863 break;
1864 crReturn(1); /* get another character */
374330e2 1865 }
8df7a775 1866
51470298 1867 s->vstrsize = 16;
1868 s->vstring = smalloc(s->vstrsize);
1869 strcpy(s->vstring, "SSH-");
1870 s->vslen = 4;
1871 s->i = 0;
374330e2 1872 while (1) {
8df7a775 1873 crReturn(1); /* get another char */
51470298 1874 if (s->vslen >= s->vstrsize - 1) {
1875 s->vstrsize += 16;
1876 s->vstring = srealloc(s->vstring, s->vstrsize);
32874aea 1877 }
51470298 1878 s->vstring[s->vslen++] = c;
1879 if (s->i >= 0) {
374330e2 1880 if (c == '-') {
51470298 1881 s->version[s->i] = '\0';
1882 s->i = -1;
1883 } else if (s->i < sizeof(s->version) - 1)
1884 s->version[s->i++] = c;
c4ffc4d0 1885 } else if (c == '\012')
374330e2 1886 break;
1887 }
1888
51470298 1889 ssh->agentfwd_enabled = FALSE;
1890 ssh->rdpkt2_state.incoming_sequence = 0;
960e736a 1891
51470298 1892 s->vstring[s->vslen] = 0;
1893 s->vstring[strcspn(s->vstring, "\r\n")] = '\0';/* remove EOL chars */
1894 {
1895 char *vlog;
1896 vlog = smalloc(20 + s->vslen);
1897 sprintf(vlog, "Server version: %s", s->vstring);
1898 logevent(vlog);
1899 sfree(vlog);
1900 }
1901 ssh_detect_bugs(ssh, s->vstring);
c5e9c988 1902
adf799dd 1903 /*
38d228a2 1904 * Decide which SSH protocol version to support.
adf799dd 1905 */
38d228a2 1906
1907 /* Anything strictly below "2.0" means protocol 1 is supported. */
51470298 1908 s->proto1 = ssh_versioncmp(s->version, "2.0") < 0;
38d228a2 1909 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
51470298 1910 s->proto2 = ssh_versioncmp(s->version, "1.99") >= 0;
38d228a2 1911
86916870 1912 if (ssh->cfg.sshprot == 0 && !s->proto1) {
a8327734 1913 bombout((ssh,"SSH protocol version 1 required by user but not provided by server"));
38d228a2 1914 crReturn(0);
1915 }
86916870 1916 if (ssh->cfg.sshprot == 3 && !s->proto2) {
a8327734 1917 bombout((ssh,"SSH protocol version 2 required by user but not provided by server"));
38d228a2 1918 crReturn(0);
1919 }
1920
86916870 1921 if (s->proto2 && (ssh->cfg.sshprot >= 2 || !s->proto1)) {
32874aea 1922 /*
38d228a2 1923 * Use v2 protocol.
32874aea 1924 */
1925 char verstring[80], vlog[100];
1926 sprintf(verstring, "SSH-2.0-%s", sshver);
51470298 1927 SHA_Init(&ssh->exhashbase);
32874aea 1928 /*
1929 * Hash our version string and their version string.
1930 */
51470298 1931 sha_string(&ssh->exhashbase, verstring, strlen(verstring));
1932 sha_string(&ssh->exhashbase, s->vstring, strcspn(s->vstring, "\r\n"));
32874aea 1933 sprintf(vlog, "We claim version: %s", verstring);
1934 logevent(vlog);
c4ffc4d0 1935 strcat(verstring, "\012");
32874aea 1936 logevent("Using SSH protocol version 2");
51470298 1937 sk_write(ssh->s, verstring, strlen(verstring));
1938 ssh->protocol = ssh2_protocol;
1939 ssh->version = 2;
1940 ssh->s_rdpkt = ssh2_rdpkt;
e5574168 1941 } else {
32874aea 1942 /*
38d228a2 1943 * Use v1 protocol.
32874aea 1944 */
1945 char verstring[80], vlog[100];
1946 sprintf(verstring, "SSH-%s-%s",
51470298 1947 (ssh_versioncmp(s->version, "1.5") <= 0 ? s->version : "1.5"),
32874aea 1948 sshver);
1949 sprintf(vlog, "We claim version: %s", verstring);
1950 logevent(vlog);
c4ffc4d0 1951 strcat(verstring, "\012");
759712a6 1952
32874aea 1953 logevent("Using SSH protocol version 1");
51470298 1954 sk_write(ssh->s, verstring, strlen(verstring));
1955 ssh->protocol = ssh1_protocol;
1956 ssh->version = 1;
1957 ssh->s_rdpkt = ssh1_rdpkt;
e5574168 1958 }
51470298 1959 ssh->state = SSH_STATE_BEFORE_SIZE;
8df7a775 1960
51470298 1961 sfree(s->vstring);
50526e47 1962
8df7a775 1963 crFinish(0);
1964}
1965
51470298 1966static void ssh_gotdata(Ssh ssh, unsigned char *data, int datalen)
8df7a775 1967{
51470298 1968 crBegin(ssh->ssh_gotdata_crstate);
8df7a775 1969
1970 /*
1971 * To begin with, feed the characters one by one to the
1972 * protocol initialisation / selection function do_ssh_init().
1973 * When that returns 0, we're done with the initial greeting
1974 * exchange and can move on to packet discipline.
1975 */
1976 while (1) {
51470298 1977 int ret; /* need not be kept across crReturn */
8df7a775 1978 if (datalen == 0)
1979 crReturnV; /* more data please */
51470298 1980 ret = do_ssh_init(ssh, *data);
32874aea 1981 data++;
1982 datalen--;
8df7a775 1983 if (ret == 0)
1984 break;
1985 }
1986
1987 /*
1988 * We emerge from that loop when the initial negotiation is
1989 * over and we have selected an s_rdpkt function. Now pass
1990 * everything to s_rdpkt, and then pass the resulting packets
1991 * to the proper protocol handler.
1992 */
1993 if (datalen == 0)
1994 crReturnV;
1995 while (1) {
1996 while (datalen > 0) {
51470298 1997 if (ssh->s_rdpkt(ssh, &data, &datalen) == 0) {
1998 if (ssh->state == SSH_STATE_CLOSED) {
e14d0f19 1999 return;
2000 }
51470298 2001 ssh->protocol(ssh, NULL, 0, 1);
2002 if (ssh->state == SSH_STATE_CLOSED) {
8df7a775 2003 return;
2004 }
2005 }
2006 }
2007 crReturnV;
2008 }
2009 crFinishV;
2010}
2011
32874aea 2012static int ssh_closing(Plug plug, char *error_msg, int error_code,
2013 int calling_back)
2014{
51470298 2015 Ssh ssh = (Ssh) plug;
2016 ssh->state = SSH_STATE_CLOSED;
2017 if (ssh->s) {
2018 sk_close(ssh->s);
2019 ssh->s = NULL;
f3ab576e 2020 }
7e78000d 2021 if (error_msg) {
32874aea 2022 /* A socket error has occurred. */
247308b5 2023 logevent(error_msg);
a8327734 2024 connection_fatal(ssh->frontend, error_msg);
7e78000d 2025 } else {
2026 /* Otherwise, the remote side closed the connection normally. */
8df7a775 2027 }
7e78000d 2028 return 0;
2029}
2030
32874aea 2031static int ssh_receive(Plug plug, int urgent, char *data, int len)
2032{
51470298 2033 Ssh ssh = (Ssh) plug;
d8baa528 2034 ssh_gotdata(ssh, (unsigned char *)data, len);
51470298 2035 if (ssh->state == SSH_STATE_CLOSED) {
2036 if (ssh->s) {
2037 sk_close(ssh->s);
2038 ssh->s = NULL;
32874aea 2039 }
2040 return 0;
3257deae 2041 }
fef97f43 2042 return 1;
374330e2 2043}
2044
5471d09a 2045static void ssh_sent(Plug plug, int bufsize)
2046{
51470298 2047 Ssh ssh = (Ssh) plug;
5471d09a 2048 /*
2049 * If the send backlog on the SSH socket itself clears, we
2050 * should unthrottle the whole world if it was throttled.
2051 */
2052 if (bufsize < SSH_MAX_BACKLOG)
51470298 2053 ssh_throttle_all(ssh, 0, bufsize);
5471d09a 2054}
2055
fb09bf1c 2056/*
8df7a775 2057 * Connect to specified host and port.
2058 * Returns an error message, or NULL on success.
6e1ebb76 2059 * Also places the canonical host name into `realhost'. It must be
2060 * freed by the caller.
8df7a775 2061 */
51470298 2062static char *connect_to_host(Ssh ssh, char *host, int port,
2063 char **realhost, int nodelay)
8df7a775 2064{
51470298 2065 static const struct plug_function_table fn_table = {
7e78000d 2066 ssh_closing,
5471d09a 2067 ssh_receive,
2068 ssh_sent,
2069 NULL
51470298 2070 };
7e78000d 2071
8df7a775 2072 SockAddr addr;
2073 char *err;
8df7a775 2074
51470298 2075 ssh->savedhost = smalloc(1 + strlen(host));
2076 if (!ssh->savedhost)
8df7a775 2077 fatalbox("Out of memory");
51470298 2078 strcpy(ssh->savedhost, host);
8df7a775 2079
2080 if (port < 0)
2081 port = 22; /* default ssh port */
51470298 2082 ssh->savedport = port;
8df7a775 2083
2084 /*
2085 * Try to find host.
2086 */
57356d63 2087 logeventf(ssh, "Looking up host \"%s\"", host);
e8fa8f62 2088 addr = name_lookup(host, port, realhost, &ssh->cfg);
70e5d0fd 2089 if ((err = sk_addr_error(addr)) != NULL)
8df7a775 2090 return err;
2091
8df7a775 2092 /*
2093 * Open socket.
2094 */
3ad9d396 2095 {
57356d63 2096 char addrbuf[100];
3ad9d396 2097 sk_getaddr(addr, addrbuf, 100);
57356d63 2098 logeventf(ssh, "Connecting to %s port %d", addrbuf, port);
3ad9d396 2099 }
51470298 2100 ssh->fn = &fn_table;
e8fa8f62 2101 ssh->s = new_connection(addr, *realhost, port,
2102 0, 1, nodelay, (Plug) ssh, &ssh->cfg);
70e5d0fd 2103 if ((err = sk_socket_error(ssh->s)) != NULL) {
51470298 2104 ssh->s = NULL;
8df7a775 2105 return err;
67c4ba2e 2106 }
8df7a775 2107
8df7a775 2108 return NULL;
2109}
2110
2111/*
5471d09a 2112 * Throttle or unthrottle the SSH connection.
2113 */
51470298 2114static void ssh1_throttle(Ssh ssh, int adjust)
5471d09a 2115{
51470298 2116 int old_count = ssh->v1_throttle_count;
2117 ssh->v1_throttle_count += adjust;
2118 assert(ssh->v1_throttle_count >= 0);
2119 if (ssh->v1_throttle_count && !old_count) {
2120 sk_set_frozen(ssh->s, 1);
2121 } else if (!ssh->v1_throttle_count && old_count) {
2122 sk_set_frozen(ssh->s, 0);
5471d09a 2123 }
2124}
2125
2126/*
2127 * Throttle or unthrottle _all_ local data streams (for when sends
2128 * on the SSH connection itself back up).
2129 */
51470298 2130static void ssh_throttle_all(Ssh ssh, int enable, int bufsize)
5471d09a 2131{
2132 int i;
2133 struct ssh_channel *c;
2134
51470298 2135 if (enable == ssh->throttled_all)
5471d09a 2136 return;
51470298 2137 ssh->throttled_all = enable;
2138 ssh->overall_bufsize = bufsize;
2139 if (!ssh->channels)
5471d09a 2140 return;
51470298 2141 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
5471d09a 2142 switch (c->type) {
2143 case CHAN_MAINSESSION:
2144 /*
2145 * This is treated separately, outside the switch.
2146 */
2147 break;
2148 case CHAN_X11:
2149 x11_override_throttle(c->u.x11.s, enable);
2150 break;
2151 case CHAN_AGENT:
2152 /* Agent channels require no buffer management. */
2153 break;
2154 case CHAN_SOCKDATA:
2155 pfd_override_throttle(c->u.x11.s, enable);
2156 break;
2157 }
2158 }
2159}
2160
2161/*
51470298 2162 * Username and password input, abstracted off into routines
2163 * reusable in several places - even between SSH1 and SSH2.
0405e71f 2164 */
0405e71f 2165
2166/* Set up a username or password input loop on a given buffer. */
ae9ae89f 2167static void setup_userpass_input(Ssh ssh, char *buffer, int buflen, int echo)
0405e71f 2168{
51470298 2169 ssh->userpass_input_buffer = buffer;
2170 ssh->userpass_input_buflen = buflen;
2171 ssh->userpass_input_bufpos = 0;
2172 ssh->userpass_input_echo = echo;
0405e71f 2173}
2174
2175/*
2176 * Process some terminal data in the course of username/password
2177 * input. Returns >0 for success (line of input returned in
2178 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2179 * for inconclusive (keep waiting for more input please).
2180 */
ae9ae89f 2181static int process_userpass_input(Ssh ssh, unsigned char *in, int inlen)
0405e71f 2182{
2183 char c;
2184
2185 while (inlen--) {
2186 switch (c = *in++) {
2187 case 10:
2188 case 13:
51470298 2189 ssh->userpass_input_buffer[ssh->userpass_input_bufpos] = 0;
2190 ssh->userpass_input_buffer[ssh->userpass_input_buflen-1] = 0;
0405e71f 2191 return +1;
2192 break;
2193 case 8:
2194 case 127:
51470298 2195 if (ssh->userpass_input_bufpos > 0) {
2196 if (ssh->userpass_input_echo)
2197 c_write_str(ssh, "\b \b");
2198 ssh->userpass_input_bufpos--;
0405e71f 2199 }
2200 break;
2201 case 21:
2202 case 27:
51470298 2203 while (ssh->userpass_input_bufpos > 0) {
2204 if (ssh->userpass_input_echo)
2205 c_write_str(ssh, "\b \b");
2206 ssh->userpass_input_bufpos--;
0405e71f 2207 }
2208 break;
2209 case 3:
2210 case 4:
2211 return -1;
2212 break;
2213 default:
4692a14a 2214 /*
2215 * This simplistic check for printability is disabled
2216 * when we're doing password input, because some people
2217 * have control characters in their passwords.o
2218 */
2219 if ((!ssh->userpass_input_echo ||
2220 (c >= ' ' && c <= '~') ||
0405e71f 2221 ((unsigned char) c >= 160))
51470298 2222 && ssh->userpass_input_bufpos < ssh->userpass_input_buflen-1) {
2223 ssh->userpass_input_buffer[ssh->userpass_input_bufpos++] = c;
2224 if (ssh->userpass_input_echo)
2225 c_write(ssh, &c, 1);
0405e71f 2226 }
2227 break;
2228 }
2229 }
2230 return 0;
2231}
2232
2233/*
fb09bf1c 2234 * Handle the key exchange and user authentication phases.
2235 */
51470298 2236static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
fb09bf1c 2237{
2d466ffd 2238 int i, j;
374330e2 2239 unsigned char cookie[8];
2240 struct RSAKey servkey, hostkey;
2241 struct MD5Context md5c;
51470298 2242 struct do_ssh1_login_state {
2243 int len;
2244 unsigned char *rsabuf, *keystr1, *keystr2;
2245 unsigned long supported_ciphers_mask, supported_auths_mask;
2246 int tried_publickey, tried_agent;
2247 int tis_auth_refused, ccard_auth_refused;
2248 unsigned char session_id[16];
2249 int cipher_type;
2250 char username[100];
2251 void *publickey_blob;
2252 int publickey_bloblen;
2253 char password[100];
2254 char prompt[200];
2255 int pos;
2256 char c;
2257 int pwpkt_type;
2258 unsigned char request[5], *response, *p;
2259 int responselen;
2260 int keyi, nkeys;
2261 int authed;
2262 struct RSAKey key;
2263 Bignum challenge;
2264 char *commentp;
2265 int commentlen;
2266 };
2267 crState(do_ssh1_login_state);
2268
2269 crBegin(ssh->do_ssh1_login_crstate);
374330e2 2270
32874aea 2271 if (!ispkt)
2272 crWaitUntil(ispkt);
374330e2 2273
51470298 2274 if (ssh->pktin.type != SSH1_SMSG_PUBLIC_KEY) {
a8327734 2275 bombout((ssh,"Public key packet not received"));
32874aea 2276 crReturn(0);
8d5de777 2277 }
374330e2 2278
c5e9c988 2279 logevent("Received public keys");
374330e2 2280
51470298 2281 memcpy(cookie, ssh->pktin.body, 8);
374330e2 2282
51470298 2283 i = makekey(ssh->pktin.body + 8, &servkey, &s->keystr1, 0);
2284 j = makekey(ssh->pktin.body + 8 + i, &hostkey, &s->keystr2, 0);
374330e2 2285
c5e9c988 2286 /*
1c2a93c4 2287 * Log the host key fingerprint.
c5e9c988 2288 */
c5e9c988 2289 {
2290 char logmsg[80];
1c2a93c4 2291 logevent("Host key fingerprint is:");
c5e9c988 2292 strcpy(logmsg, " ");
32874aea 2293 hostkey.comment = NULL;
2294 rsa_fingerprint(logmsg + strlen(logmsg),
2295 sizeof(logmsg) - strlen(logmsg), &hostkey);
c5e9c988 2296 logevent(logmsg);
2297 }
2298
51470298 2299 ssh->v1_remote_protoflags = GET_32BIT(ssh->pktin.body + 8 + i + j);
2300 s->supported_ciphers_mask = GET_32BIT(ssh->pktin.body + 12 + i + j);
2301 s->supported_auths_mask = GET_32BIT(ssh->pktin.body + 16 + i + j);
bea1ef5f 2302
51470298 2303 ssh->v1_local_protoflags =
2304 ssh->v1_remote_protoflags & SSH1_PROTOFLAGS_SUPPORTED;
2305 ssh->v1_local_protoflags |= SSH1_PROTOFLAG_SCREEN_NUMBER;
b96dc54c 2306
c5e9c988 2307 MD5Init(&md5c);
51470298 2308 MD5Update(&md5c, s->keystr2, hostkey.bytes);
2309 MD5Update(&md5c, s->keystr1, servkey.bytes);
2310 MD5Update(&md5c, ssh->pktin.body, 8);
2311 MD5Final(s->session_id, &md5c);
374330e2 2312
32874aea 2313 for (i = 0; i < 32; i++)
51470298 2314 ssh->session_key[i] = random_byte();
374330e2 2315
51470298 2316 s->len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
374330e2 2317
51470298 2318 s->rsabuf = smalloc(s->len);
2319 if (!s->rsabuf)
374330e2 2320 fatalbox("Out of memory");
2321
89ee5268 2322 /*
2323 * Verify the host key.
2324 */
2325 {
32874aea 2326 /*
2327 * First format the key into a string.
2328 */
2329 int len = rsastr_len(&hostkey);
2330 char fingerprint[100];
2331 char *keystr = smalloc(len);
2332 if (!keystr)
2333 fatalbox("Out of memory");
2334 rsastr_fmt(keystr, &hostkey);
2335 rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
a8327734 2336 verify_ssh_host_key(ssh->frontend,
2337 ssh->savedhost, ssh->savedport, "rsa", keystr,
32874aea 2338 fingerprint);
2339 sfree(keystr);
2340 }
2341
2342 for (i = 0; i < 32; i++) {
51470298 2343 s->rsabuf[i] = ssh->session_key[i];
374330e2 2344 if (i < 16)
51470298 2345 s->rsabuf[i] ^= s->session_id[i];
374330e2 2346 }
2347
2348 if (hostkey.bytes > servkey.bytes) {
51470298 2349 rsaencrypt(s->rsabuf, 32, &servkey);
2350 rsaencrypt(s->rsabuf, servkey.bytes, &hostkey);
374330e2 2351 } else {
51470298 2352 rsaencrypt(s->rsabuf, 32, &hostkey);
2353 rsaencrypt(s->rsabuf, hostkey.bytes, &servkey);
374330e2 2354 }
2355
c5e9c988 2356 logevent("Encrypted session key");
2357
ca20bfcf 2358 {
2359 int cipher_chosen = 0, warn = 0;
2360 char *cipher_string = NULL;
51470298 2361 int i;
ca20bfcf 2362 for (i = 0; !cipher_chosen && i < CIPHER_MAX; i++) {
86916870 2363 int next_cipher = ssh->cfg.ssh_cipherlist[i];
ca20bfcf 2364 if (next_cipher == CIPHER_WARN) {
2365 /* If/when we choose a cipher, warn about it */
2366 warn = 1;
2367 } else if (next_cipher == CIPHER_AES) {
2368 /* XXX Probably don't need to mention this. */
2369 logevent("AES not supported in SSH1, skipping");
2370 } else {
2371 switch (next_cipher) {
51470298 2372 case CIPHER_3DES: s->cipher_type = SSH_CIPHER_3DES;
ca20bfcf 2373 cipher_string = "3DES"; break;
51470298 2374 case CIPHER_BLOWFISH: s->cipher_type = SSH_CIPHER_BLOWFISH;
ca20bfcf 2375 cipher_string = "Blowfish"; break;
51470298 2376 case CIPHER_DES: s->cipher_type = SSH_CIPHER_DES;
ca20bfcf 2377 cipher_string = "single-DES"; break;
2378 }
51470298 2379 if (s->supported_ciphers_mask & (1 << s->cipher_type))
ca20bfcf 2380 cipher_chosen = 1;
2381 }
2382 }
2383 if (!cipher_chosen) {
51470298 2384 if ((s->supported_ciphers_mask & (1 << SSH_CIPHER_3DES)) == 0)
a8327734 2385 bombout((ssh,"Server violates SSH 1 protocol by not "
ca20bfcf 2386 "supporting 3DES encryption"));
2387 else
2388 /* shouldn't happen */
a8327734 2389 bombout((ssh,"No supported ciphers found"));
a99a05c0 2390 crReturn(0);
2391 }
ca20bfcf 2392
2393 /* Warn about chosen cipher if necessary. */
2394 if (warn)
a8327734 2395 askcipher(ssh->frontend, cipher_string, 0);
bea1ef5f 2396 }
ca20bfcf 2397
51470298 2398 switch (s->cipher_type) {
32874aea 2399 case SSH_CIPHER_3DES:
2400 logevent("Using 3DES encryption");
2401 break;
2402 case SSH_CIPHER_DES:
2403 logevent("Using single-DES encryption");
2404 break;
2405 case SSH_CIPHER_BLOWFISH:
2406 logevent("Using Blowfish encryption");
2407 break;
c5e9c988 2408 }
bea1ef5f 2409
51470298 2410 send_packet(ssh, SSH1_CMSG_SESSION_KEY,
2411 PKT_CHAR, s->cipher_type,
32874aea 2412 PKT_DATA, cookie, 8,
51470298 2413 PKT_CHAR, (s->len * 8) >> 8, PKT_CHAR, (s->len * 8) & 0xFF,
2414 PKT_DATA, s->rsabuf, s->len,
2415 PKT_INT, ssh->v1_local_protoflags, PKT_END);
fb09bf1c 2416
c5e9c988 2417 logevent("Trying to enable encryption...");
374330e2 2418
51470298 2419 sfree(s->rsabuf);
374330e2 2420
51470298 2421 ssh->cipher = (s->cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
2422 s->cipher_type == SSH_CIPHER_DES ? &ssh_des :
2423 &ssh_3des);
371e569c 2424 ssh->v1_cipher_ctx = ssh->cipher->make_context();
2425 ssh->cipher->sesskey(ssh->v1_cipher_ctx, ssh->session_key);
57356d63 2426 logeventf(ssh, "Initialised %s encryption", ssh->cipher->text_name);
374330e2 2427
0183b242 2428 ssh->crcda_ctx = crcda_make_context();
2429 logevent("Installing CRC compensation attack detector");
2430
fb09bf1c 2431 crWaitUntil(ispkt);
374330e2 2432
51470298 2433 if (ssh->pktin.type != SSH1_SMSG_SUCCESS) {
a8327734 2434 bombout((ssh,"Encryption not successfully enabled"));
32874aea 2435 crReturn(0);
8d5de777 2436 }
374330e2 2437
c5e9c988 2438 logevent("Successfully started encryption");
2439
374330e2 2440 fflush(stdout);
2441 {
86916870 2442 if ((flags & FLAG_INTERACTIVE) && !*ssh->cfg.username) {
c0a81592 2443 if (ssh_get_line && !ssh_getline_pw_only) {
32874aea 2444 if (!ssh_get_line("login as: ",
51470298 2445 s->username, sizeof(s->username), FALSE)) {
32874aea 2446 /*
2447 * get_line failed to get a username.
2448 * Terminate.
2449 */
2450 logevent("No username provided. Abandoning session.");
51470298 2451 ssh->state = SSH_STATE_CLOSED;
32874aea 2452 crReturn(1);
2453 }
2454 } else {
51470298 2455 int ret; /* need not be kept over crReturn */
2456 c_write_str(ssh, "login as: ");
2457 ssh->send_ok = 1;
0405e71f 2458
51470298 2459 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
0405e71f 2460 do {
32874aea 2461 crWaitUntil(!ispkt);
51470298 2462 ret = process_userpass_input(ssh, in, inlen);
0405e71f 2463 } while (ret == 0);
2464 if (ret < 0)
2465 cleanup_exit(0);
51470298 2466 c_write_str(ssh, "\r\n");
32874aea 2467 }
2468 } else {
86916870 2469 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
51470298 2470 s->username[sizeof(s->username)-1] = '\0';
374330e2 2471 }
fb09bf1c 2472
51470298 2473 send_packet(ssh, SSH1_CMSG_USER, PKT_STR, s->username, PKT_END);
c5e9c988 2474 {
51470298 2475 char userlog[22 + sizeof(s->username)];
2476 sprintf(userlog, "Sent username \"%s\"", s->username);
c5e9c988 2477 logevent(userlog);
32874aea 2478 if (flags & FLAG_INTERACTIVE &&
2479 (!((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)))) {
3c8e959b 2480 strcat(userlog, "\r\n");
51470298 2481 c_write_str(ssh, userlog);
3c8e959b 2482 }
c5e9c988 2483 }
374330e2 2484 }
2485
fb09bf1c 2486 crWaitUntil(ispkt);
374330e2 2487
51470298 2488 if ((ssh->remote_bugs & BUG_CHOKES_ON_RSA)) {
0df73905 2489 /* We must not attempt PK auth. Pretend we've already tried it. */
51470298 2490 s->tried_publickey = s->tried_agent = 1;
0df73905 2491 } else {
51470298 2492 s->tried_publickey = s->tried_agent = 0;
0df73905 2493 }
51470298 2494 s->tis_auth_refused = s->ccard_auth_refused = 0;
86916870 2495 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
9a30e26b 2496 if (!filename_is_null(ssh->cfg.keyfile)) {
2497 if (!rsakey_pubblob(&ssh->cfg.keyfile,
51470298 2498 &s->publickey_blob, &s->publickey_bloblen))
2499 s->publickey_blob = NULL;
396778f1 2500 } else
51470298 2501 s->publickey_blob = NULL;
7cca0d81 2502
51470298 2503 while (ssh->pktin.type == SSH1_SMSG_FAILURE) {
2504 s->pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
614a20a0 2505
51470298 2506 if (agent_exists() && !s->tried_agent) {
32874aea 2507 /*
2508 * Attempt RSA authentication using Pageant.
2509 */
32874aea 2510 void *r;
2511
51470298 2512 s->authed = FALSE;
2513 s->tried_agent = 1;
32874aea 2514 logevent("Pageant is running. Requesting keys.");
2515
2516 /* Request the keys held by the agent. */
51470298 2517 PUT_32BIT(s->request, 1);
2518 s->request[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES;
2519 agent_query(s->request, 5, &r, &s->responselen);
2520 s->response = (unsigned char *) r;
2521 if (s->response && s->responselen >= 5 &&
2522 s->response[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER) {
2523 s->p = s->response + 5;
2524 s->nkeys = GET_32BIT(s->p);
2525 s->p += 4;
32874aea 2526 {
2527 char buf[64];
51470298 2528 sprintf(buf, "Pageant has %d SSH1 keys", s->nkeys);
32874aea 2529 logevent(buf);
2530 }
51470298 2531 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
32874aea 2532 {
2533 char buf[64];
51470298 2534 sprintf(buf, "Trying Pageant key #%d", s->keyi);
32874aea 2535 logevent(buf);
2536 }
51470298 2537 if (s->publickey_blob &&
2538 !memcmp(s->p, s->publickey_blob,
2539 s->publickey_bloblen)) {
396778f1 2540 logevent("This key matches configured key file");
51470298 2541 s->tried_publickey = 1;
396778f1 2542 }
51470298 2543 s->p += 4;
2544 s->p += ssh1_read_bignum(s->p, &s->key.exponent);
2545 s->p += ssh1_read_bignum(s->p, &s->key.modulus);
2546 s->commentlen = GET_32BIT(s->p);
2547 s->p += 4;
d8baa528 2548 s->commentp = (char *)s->p;
51470298 2549 s->p += s->commentlen;
2550 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
2551 PKT_BIGNUM, s->key.modulus, PKT_END);
32874aea 2552 crWaitUntil(ispkt);
51470298 2553 if (ssh->pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
32874aea 2554 logevent("Key refused");
2555 continue;
2556 }
2557 logevent("Received RSA challenge");
51470298 2558 ssh1_read_bignum(ssh->pktin.body, &s->challenge);
32874aea 2559 {
2560 char *agentreq, *q, *ret;
2d466ffd 2561 void *vret;
32874aea 2562 int len, retlen;
2563 len = 1 + 4; /* message type, bit count */
51470298 2564 len += ssh1_bignum_length(s->key.exponent);
2565 len += ssh1_bignum_length(s->key.modulus);
2566 len += ssh1_bignum_length(s->challenge);
32874aea 2567 len += 16; /* session id */
2568 len += 4; /* response format */
2569 agentreq = smalloc(4 + len);
2570 PUT_32BIT(agentreq, len);
2571 q = agentreq + 4;
2572 *q++ = SSH1_AGENTC_RSA_CHALLENGE;
51470298 2573 PUT_32BIT(q, bignum_bitcount(s->key.modulus));
32874aea 2574 q += 4;
51470298 2575 q += ssh1_write_bignum(q, s->key.exponent);
2576 q += ssh1_write_bignum(q, s->key.modulus);
2577 q += ssh1_write_bignum(q, s->challenge);
2578 memcpy(q, s->session_id, 16);
32874aea 2579 q += 16;
2580 PUT_32BIT(q, 1); /* response format */
2d466ffd 2581 agent_query(agentreq, len + 4, &vret, &retlen);
2582 ret = vret;
32874aea 2583 sfree(agentreq);
2584 if (ret) {
2585 if (ret[4] == SSH1_AGENT_RSA_RESPONSE) {
2586 logevent("Sending Pageant's response");
51470298 2587 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
32874aea 2588 PKT_DATA, ret + 5, 16,
2589 PKT_END);
2590 sfree(ret);
2591 crWaitUntil(ispkt);
51470298 2592 if (ssh->pktin.type == SSH1_SMSG_SUCCESS) {
32874aea 2593 logevent
2594 ("Pageant's response accepted");
2595 if (flags & FLAG_VERBOSE) {
51470298 2596 c_write_str(ssh, "Authenticated using"
2597 " RSA key \"");
2598 c_write(ssh, s->commentp,
2599 s->commentlen);
2600 c_write_str(ssh, "\" from agent\r\n");
32874aea 2601 }
51470298 2602 s->authed = TRUE;
32874aea 2603 } else
2604 logevent
2605 ("Pageant's response not accepted");
2606 } else {
2607 logevent
2608 ("Pageant failed to answer challenge");
2609 sfree(ret);
2610 }
2611 } else {
2612 logevent("No reply received from Pageant");
2613 }
2614 }
51470298 2615 freebn(s->key.exponent);
2616 freebn(s->key.modulus);
2617 freebn(s->challenge);
2618 if (s->authed)
32874aea 2619 break;
2620 }
2621 }
51470298 2622 if (s->authed)
32874aea 2623 break;
2624 }
9a30e26b 2625 if (!filename_is_null(ssh->cfg.keyfile) && !s->tried_publickey)
51470298 2626 s->pwpkt_type = SSH1_CMSG_AUTH_RSA;
32874aea 2627
86916870 2628 if (ssh->cfg.try_tis_auth &&
51470298 2629 (s->supported_auths_mask & (1 << SSH1_AUTH_TIS)) &&
2630 !s->tis_auth_refused) {
2631 s->pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
32874aea 2632 logevent("Requested TIS authentication");
51470298 2633 send_packet(ssh, SSH1_CMSG_AUTH_TIS, PKT_END);
32874aea 2634 crWaitUntil(ispkt);
51470298 2635 if (ssh->pktin.type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
32874aea 2636 logevent("TIS authentication declined");
2637 if (flags & FLAG_INTERACTIVE)
51470298 2638 c_write_str(ssh, "TIS authentication refused.\r\n");
2639 s->tis_auth_refused = 1;
614a20a0 2640 continue;
32874aea 2641 } else {
51470298 2642 int challengelen = GET_32BIT(ssh->pktin.body);
32874aea 2643 logevent("Received TIS challenge");
51470298 2644 if (challengelen > sizeof(s->prompt) - 1)
2645 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
2646 memcpy(s->prompt, ssh->pktin.body + 4, challengelen);
614a20a0 2647 /* Prompt heuristic comes from OpenSSH */
51470298 2648 strncpy(s->prompt + challengelen,
2649 memchr(s->prompt, '\n', challengelen) ?
614a20a0 2650 "": "\r\nResponse: ",
51470298 2651 (sizeof s->prompt) - challengelen);
2652 s->prompt[(sizeof s->prompt) - 1] = '\0';
32874aea 2653 }
2654 }
86916870 2655 if (ssh->cfg.try_tis_auth &&
51470298 2656 (s->supported_auths_mask & (1 << SSH1_AUTH_CCARD)) &&
2657 !s->ccard_auth_refused) {
2658 s->pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
32874aea 2659 logevent("Requested CryptoCard authentication");
51470298 2660 send_packet(ssh, SSH1_CMSG_AUTH_CCARD, PKT_END);
32874aea 2661 crWaitUntil(ispkt);
51470298 2662 if (ssh->pktin.type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
32874aea 2663 logevent("CryptoCard authentication declined");
51470298 2664 c_write_str(ssh, "CryptoCard authentication refused.\r\n");
2665 s->ccard_auth_refused = 1;
614a20a0 2666 continue;
32874aea 2667 } else {
51470298 2668 int challengelen = GET_32BIT(ssh->pktin.body);
32874aea 2669 logevent("Received CryptoCard challenge");
51470298 2670 if (challengelen > sizeof(s->prompt) - 1)
2671 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
2672 memcpy(s->prompt, ssh->pktin.body + 4, challengelen);
2673 strncpy(s->prompt + challengelen,
2674 memchr(s->prompt, '\n', challengelen) ?
614a20a0 2675 "" : "\r\nResponse: ",
51470298 2676 sizeof(s->prompt) - challengelen);
2677 s->prompt[sizeof(s->prompt) - 1] = '\0';
32874aea 2678 }
2679 }
51470298 2680 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
2681 sprintf(s->prompt, "%.90s@%.90s's password: ",
2682 s->username, ssh->savedhost);
32874aea 2683 }
51470298 2684 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
32874aea 2685 char *comment = NULL;
231ee168 2686 int type;
2687 char msgbuf[256];
32874aea 2688 if (flags & FLAG_VERBOSE)
51470298 2689 c_write_str(ssh, "Trying public key authentication.\r\n");
6c6d9ed9 2690 logeventf(ssh, "Trying public key \"%s\"",
2691 filename_to_str(&ssh->cfg.keyfile));
9a30e26b 2692 type = key_type(&ssh->cfg.keyfile);
231ee168 2693 if (type != SSH_KEYTYPE_SSH1) {
2694 sprintf(msgbuf, "Key is of wrong type (%s)",
2695 key_type_to_str(type));
2696 logevent(msgbuf);
51470298 2697 c_write_str(ssh, msgbuf);
2698 c_write_str(ssh, "\r\n");
2699 s->tried_publickey = 1;
231ee168 2700 continue;
2701 }
9a30e26b 2702 if (!rsakey_encrypted(&ssh->cfg.keyfile, &comment)) {
32874aea 2703 if (flags & FLAG_VERBOSE)
51470298 2704 c_write_str(ssh, "No passphrase required.\r\n");
32874aea 2705 goto tryauth;
2706 }
51470298 2707 sprintf(s->prompt, "Passphrase for key \"%.100s\": ", comment);
32874aea 2708 sfree(comment);
2709 }
a52f067e 2710
614a20a0 2711 /*
2712 * Show password prompt, having first obtained it via a TIS
2713 * or CryptoCard exchange if we're doing TIS or CryptoCard
2714 * authentication.
2715 */
fa17a66e 2716 if (ssh_get_line) {
51470298 2717 if (!ssh_get_line(s->prompt, s->password,
2718 sizeof(s->password), TRUE)) {
32874aea 2719 /*
2720 * get_line failed to get a password (for example
2721 * because one was supplied on the command line
2722 * which has already failed to work). Terminate.
2723 */
51470298 2724 send_packet(ssh, SSH1_MSG_DISCONNECT,
2bc6a386 2725 PKT_STR, "No more passwords available to try",
2726 PKT_END);
247308b5 2727 logevent("Unable to authenticate");
a8327734 2728 connection_fatal(ssh->frontend, "Unable to authenticate");
51470298 2729 ssh->state = SSH_STATE_CLOSED;
32874aea 2730 crReturn(1);
2731 }
fb09bf1c 2732 } else {
614a20a0 2733 /* Prompt may have come from server. We've munged it a bit, so
2734 * we know it to be zero-terminated at least once. */
51470298 2735 int ret; /* need not be saved over crReturn */
2736 c_write_untrusted(ssh, s->prompt, strlen(s->prompt));
2737 s->pos = 0;
0405e71f 2738
51470298 2739 setup_userpass_input(ssh, s->password, sizeof(s->password), 0);
0405e71f 2740 do {
32874aea 2741 crWaitUntil(!ispkt);
51470298 2742 ret = process_userpass_input(ssh, in, inlen);
0405e71f 2743 } while (ret == 0);
2744 if (ret < 0)
2745 cleanup_exit(0);
51470298 2746 c_write_str(ssh, "\r\n");
32874aea 2747 }
2748
2749 tryauth:
51470298 2750 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
32874aea 2751 /*
2752 * Try public key authentication with the specified
2753 * key file.
2754 */
51470298 2755 s->tried_publickey = 1;
2756
2757 {
9a30e26b 2758 int ret = loadrsakey(&ssh->cfg.keyfile, &s->key, s->password);
51470298 2759 if (ret == 0) {
2760 c_write_str(ssh, "Couldn't load private key from ");
9fab77dc 2761 c_write_str(ssh, filename_to_str(&ssh->cfg.keyfile));
51470298 2762 c_write_str(ssh, ".\r\n");
2763 continue; /* go and try password */
2764 }
2765 if (ret == -1) {
2766 c_write_str(ssh, "Wrong passphrase.\r\n");
2767 s->tried_publickey = 0;
2768 continue; /* try again */
2769 }
32874aea 2770 }
2771
2772 /*
2773 * Send a public key attempt.
2774 */
51470298 2775 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
2776 PKT_BIGNUM, s->key.modulus, PKT_END);
32874aea 2777
2778 crWaitUntil(ispkt);
51470298 2779 if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
2780 c_write_str(ssh, "Server refused our public key.\r\n");
32874aea 2781 continue; /* go and try password */
2782 }
51470298 2783 if (ssh->pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
a8327734 2784 bombout((ssh,"Bizarre response to offer of public key"));
32874aea 2785 crReturn(0);
2786 }
32874aea 2787
51470298 2788 {
2789 int i;
2790 unsigned char buffer[32];
2791 Bignum challenge, response;
2792
2793 ssh1_read_bignum(ssh->pktin.body, &challenge);
2794 response = rsadecrypt(challenge, &s->key);
2795 freebn(s->key.private_exponent);/* burn the evidence */
32874aea 2796
51470298 2797 for (i = 0; i < 32; i++) {
2798 buffer[i] = bignum_byte(response, 31 - i);
2799 }
2800
2801 MD5Init(&md5c);
2802 MD5Update(&md5c, buffer, 32);
2803 MD5Update(&md5c, s->session_id, 16);
2804 MD5Final(buffer, &md5c);
32874aea 2805
51470298 2806 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
2807 PKT_DATA, buffer, 16, PKT_END);
2808
2809 freebn(challenge);
2810 freebn(response);
2811 }
32874aea 2812
2813 crWaitUntil(ispkt);
51470298 2814 if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
32874aea 2815 if (flags & FLAG_VERBOSE)
51470298 2816 c_write_str(ssh, "Failed to authenticate with"
2817 " our public key.\r\n");
32874aea 2818 continue; /* go and try password */
51470298 2819 } else if (ssh->pktin.type != SSH1_SMSG_SUCCESS) {
a8327734 2820 bombout((ssh,"Bizarre response to RSA authentication response"));
32874aea 2821 crReturn(0);
2822 }
2823
2824 break; /* we're through! */
2825 } else {
51470298 2826 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
32874aea 2827 /*
2828 * Defence against traffic analysis: we send a
2829 * whole bunch of packets containing strings of
2830 * different lengths. One of these strings is the
2831 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
2832 * The others are all random data in
2833 * SSH1_MSG_IGNORE packets. This way a passive
2834 * listener can't tell which is the password, and
2835 * hence can't deduce the password length.
2836 *
2837 * Anybody with a password length greater than 16
2838 * bytes is going to have enough entropy in their
2839 * password that a listener won't find it _that_
2840 * much help to know how long it is. So what we'll
2841 * do is:
2842 *
2843 * - if password length < 16, we send 15 packets
2844 * containing string lengths 1 through 15
2845 *
2846 * - otherwise, we let N be the nearest multiple
2847 * of 8 below the password length, and send 8
2848 * packets containing string lengths N through
2849 * N+7. This won't obscure the order of
2850 * magnitude of the password length, but it will
2851 * introduce a bit of extra uncertainty.
2852 *
2853 * A few servers (the old 1.2.18 through 1.2.22)
2854 * can't deal with SSH1_MSG_IGNORE. For these
2855 * servers, we need an alternative defence. We make
2856 * use of the fact that the password is interpreted
2857 * as a C string: so we can append a NUL, then some
2858 * random data.
bd358db1 2859 *
2860 * One server (a Cisco one) can deal with neither
2861 * SSH1_MSG_IGNORE _nor_ a padded password string.
2862 * For this server we are left with no defences
2863 * against password length sniffing.
32874aea 2864 */
51470298 2865 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE)) {
b17c8428 2866 /*
2867 * The server can deal with SSH1_MSG_IGNORE, so
2868 * we can use the primary defence.
2869 */
32874aea 2870 int bottom, top, pwlen, i;
2871 char *randomstr;
2872
51470298 2873 pwlen = strlen(s->password);
32874aea 2874 if (pwlen < 16) {
2875 bottom = 0; /* zero length passwords are OK! :-) */
2876 top = 15;
2877 } else {
2878 bottom = pwlen & ~7;
2879 top = bottom + 7;
2880 }
2881
2882 assert(pwlen >= bottom && pwlen <= top);
2883
2884 randomstr = smalloc(top + 1);
2885
2886 for (i = bottom; i <= top; i++) {
2887 if (i == pwlen)
51470298 2888 defer_packet(ssh, s->pwpkt_type,
2889 PKT_STR, s->password, PKT_END);
32874aea 2890 else {
2891 for (j = 0; j < i; j++) {
2892 do {
2893 randomstr[j] = random_byte();
2894 } while (randomstr[j] == '\0');
2895 }
2896 randomstr[i] = '\0';
51470298 2897 defer_packet(ssh, SSH1_MSG_IGNORE,
32874aea 2898 PKT_STR, randomstr, PKT_END);
2899 }
2900 }
bd358db1 2901 logevent("Sending password with camouflage packets");
51470298 2902 ssh_pkt_defersend(ssh);
bd358db1 2903 }
51470298 2904 else if (!(ssh->remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
b17c8428 2905 /*
2906 * The server can't deal with SSH1_MSG_IGNORE
2907 * but can deal with padded passwords, so we
2908 * can use the secondary defence.
2909 */
bd358db1 2910 char string[64];
51470298 2911 char *ss;
bd358db1 2912 int len;
2913
51470298 2914 len = strlen(s->password);
bd358db1 2915 if (len < sizeof(string)) {
51470298 2916 ss = string;
2917 strcpy(string, s->password);
bd358db1 2918 len++; /* cover the zero byte */
2919 while (len < sizeof(string)) {
2920 string[len++] = (char) random_byte();
2921 }
2922 } else {
51470298 2923 ss = s->password;
bd358db1 2924 }
2925 logevent("Sending length-padded password");
51470298 2926 send_packet(ssh, s->pwpkt_type, PKT_INT, len,
2927 PKT_DATA, ss, len, PKT_END);
bd358db1 2928 } else {
2929 /*
2930 * The server has _both_
2931 * BUG_CHOKES_ON_SSH1_IGNORE and
2932 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
2933 * therefore nothing we can do.
2934 */
2935 int len;
51470298 2936 len = strlen(s->password);
bd358db1 2937 logevent("Sending unpadded password");
51470298 2938 send_packet(ssh, s->pwpkt_type, PKT_INT, len,
2939 PKT_DATA, s->password, len, PKT_END);
32874aea 2940 }
2941 } else {
51470298 2942 send_packet(ssh, s->pwpkt_type, PKT_STR, s->password, PKT_END);
32874aea 2943 }
2944 }
c5e9c988 2945 logevent("Sent password");
51470298 2946 memset(s->password, 0, strlen(s->password));
fb09bf1c 2947 crWaitUntil(ispkt);
51470298 2948 if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
32874aea 2949 if (flags & FLAG_VERBOSE)
51470298 2950 c_write_str(ssh, "Access denied\r\n");
c5e9c988 2951 logevent("Authentication refused");
51470298 2952 } else if (ssh->pktin.type != SSH1_SMSG_SUCCESS) {
a8327734 2953 bombout((ssh,"Strange packet received, type %d", ssh->pktin.type));
32874aea 2954 crReturn(0);
374330e2 2955 }
2956 }
2957
c5e9c988 2958 logevent("Authentication successful");
2959
fb09bf1c 2960 crFinish(1);
2961}
2962
32874aea 2963void sshfwd_close(struct ssh_channel *c)
2964{
51470298 2965 Ssh ssh = c->ssh;
2966
80e48603 2967 if (c && !c->closes) {
4ed34d25 2968 /*
2969 * If the channel's remoteid is -1, we have sent
2970 * CHANNEL_OPEN for this channel, but it hasn't even been
2971 * acknowledged by the server. So we must set a close flag
2972 * on it now, and then when the server acks the channel
2973 * open, we can close it then.
2974 */
36cac739 2975 if (((int)c->remoteid) != -1) {
51470298 2976 if (ssh->version == 1) {
2977 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid,
4ed34d25 2978 PKT_END);
2979 } else {
51470298 2980 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_CLOSE);
2981 ssh2_pkt_adduint32(ssh, c->remoteid);
2982 ssh2_pkt_send(ssh);
4ed34d25 2983 }
32874aea 2984 }
0357890f 2985 c->closes = 1; /* sent MSG_CLOSE */
32874aea 2986 if (c->type == CHAN_X11) {
2987 c->u.x11.s = NULL;
d74d141c 2988 logevent("Forwarded X11 connection terminated");
4ed34d25 2989 } else if (c->type == CHAN_SOCKDATA ||
2990 c->type == CHAN_SOCKDATA_DORMANT) {
d74d141c 2991 c->u.pfd.s = NULL;
2992 logevent("Forwarded port closed");
32874aea 2993 }
2994 }
2995}
2996
5471d09a 2997int sshfwd_write(struct ssh_channel *c, char *buf, int len)
32874aea 2998{
51470298 2999 Ssh ssh = c->ssh;
3000
3001 if (ssh->version == 1) {
3002 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
32874aea 3003 PKT_INT, c->remoteid,
3004 PKT_INT, len, PKT_DATA, buf, len, PKT_END);
5471d09a 3005 /*
3006 * In SSH1 we can return 0 here - implying that forwarded
3007 * connections are never individually throttled - because
3008 * the only circumstance that can cause throttling will be
3009 * the whole SSH connection backing up, in which case
3010 * _everything_ will be throttled as a whole.
3011 */
3012 return 0;
783415f8 3013 } else {
32874aea 3014 ssh2_add_channel_data(c, buf, len);
5471d09a 3015 return ssh2_try_send(c);
3016 }
3017}
3018
3019void sshfwd_unthrottle(struct ssh_channel *c, int bufsize)
3020{
51470298 3021 Ssh ssh = c->ssh;
3022
3023 if (ssh->version == 1) {
5471d09a 3024 if (c->v.v1.throttling && bufsize < SSH1_BUFFER_LIMIT) {
3025 c->v.v1.throttling = 0;
51470298 3026 ssh1_throttle(ssh, -1);
5471d09a 3027 }
3028 } else {
3029 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
783415f8 3030 }
9c964e85 3031}
3032
51470298 3033static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
32874aea 3034{
51470298 3035 crBegin(ssh->ssh1_protocol_crstate);
fb09bf1c 3036
3037 random_init();
3038
51470298 3039 while (!do_ssh1_login(ssh, in, inlen, ispkt)) {
fb09bf1c 3040 crReturnV;
85ee8208 3041 }
51470298 3042 if (ssh->state == SSH_STATE_CLOSED)
32874aea 3043 crReturnV;
fb09bf1c 3044
86916870 3045 if (ssh->cfg.agentfwd && agent_exists()) {
32874aea 3046 logevent("Requesting agent forwarding");
51470298 3047 send_packet(ssh, SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
32874aea 3048 do {
3049 crReturnV;
3050 } while (!ispkt);
51470298 3051 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3052 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
a8327734 3053 bombout((ssh,"Protocol confusion"));
32874aea 3054 crReturnV;
51470298 3055 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
32874aea 3056 logevent("Agent forwarding refused");
3057 } else {
3058 logevent("Agent forwarding enabled");
51470298 3059 ssh->agentfwd_enabled = TRUE;
db7d555c 3060 }
dacbd0e8 3061 }
3062
86916870 3063 if (ssh->cfg.x11_forward) {
32874aea 3064 char proto[20], data[64];
3065 logevent("Requesting X11 forwarding");
302121de 3066 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
86916870 3067 data, sizeof(data), ssh->cfg.x11_auth);
3068 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
51470298 3069 if (ssh->v1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) {
3070 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
32874aea 3071 PKT_STR, proto, PKT_STR, data,
86916870 3072 PKT_INT, x11_get_screen_number(ssh->cfg.x11_display),
421d6835 3073 PKT_END);
32874aea 3074 } else {
51470298 3075 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
32874aea 3076 PKT_STR, proto, PKT_STR, data, PKT_END);
3077 }
3078 do {
3079 crReturnV;
3080 } while (!ispkt);
51470298 3081 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3082 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
a8327734 3083 bombout((ssh,"Protocol confusion"));
32874aea 3084 crReturnV;
51470298 3085 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
32874aea 3086 logevent("X11 forwarding refused");
3087 } else {
3088 logevent("X11 forwarding enabled");
51470298 3089 ssh->X11_fwd_enabled = TRUE;
9c964e85 3090 }
3091 }
3092
d74d141c 3093 {
9bf696b1 3094 char type;
d74d141c 3095 int n;
a4fc0d74 3096 int sport,dport,sserv,dserv;
6ee9b735 3097 char sports[256], dports[256], saddr[256], host[256];
d74d141c 3098
51470298 3099 ssh->rportfwds = newtree234(ssh_rportcmp_ssh1);
d74d141c 3100 /* Add port forwardings. */
86916870 3101 ssh->portfwd_strptr = ssh->cfg.portfwd;
51470298 3102 while (*ssh->portfwd_strptr) {
3103 type = *ssh->portfwd_strptr++;
6ee9b735 3104 saddr[0] = '\0';
d74d141c 3105 n = 0;
6ee9b735 3106 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != '\t') {
3107 if (*ssh->portfwd_strptr == ':') {
3108 /*
3109 * We've seen a colon in the middle of the
3110 * source port number. This means that
3111 * everything we've seen until now is the
3112 * source _address_, so we'll move it into
3113 * saddr and start sports from the beginning
3114 * again.
3115 */
3116 ssh->portfwd_strptr++;
3117 sports[n] = '\0';
3118 strcpy(saddr, sports);
3119 n = 0;
3120 }
3121 if (n < 255) sports[n++] = *ssh->portfwd_strptr++;
3122 }
d74d141c 3123 sports[n] = 0;
51470298 3124 if (*ssh->portfwd_strptr == '\t')
3125 ssh->portfwd_strptr++;
d74d141c 3126 n = 0;
6ee9b735 3127 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != ':') {
3128 if (n < 255) host[n++] = *ssh->portfwd_strptr++;
3129 }
d74d141c 3130 host[n] = 0;
51470298 3131 if (*ssh->portfwd_strptr == ':')
3132 ssh->portfwd_strptr++;
d74d141c 3133 n = 0;
6ee9b735 3134 while (*ssh->portfwd_strptr) {
3135 if (n < 255) dports[n++] = *ssh->portfwd_strptr++;
3136 }
d74d141c 3137 dports[n] = 0;
51470298 3138 ssh->portfwd_strptr++;
d74d141c 3139 dport = atoi(dports);
a4fc0d74 3140 dserv = 0;
3141 if (dport == 0) {
3142 dserv = 1;
68a49acb 3143 dport = net_service_lookup(dports);
3144 if (!dport) {
57356d63 3145 logeventf(ssh, "Service lookup failed for"
3146 " destination port \"%s\"", dports);
a4fc0d74 3147 }
3148 }
d74d141c 3149 sport = atoi(sports);
a4fc0d74 3150 sserv = 0;
3151 if (sport == 0) {
3152 sserv = 1;
68a49acb 3153 sport = net_service_lookup(sports);
3154 if (!sport) {
57356d63 3155 logeventf(ssh, "Service lookup failed for source"
3156 " port \"%s\"", sports);
a4fc0d74 3157 }
3158 }
d74d141c 3159 if (sport && dport) {
3160 if (type == 'L') {
6ee9b735 3161 pfd_addforward(host, dport, *saddr ? saddr : NULL,
e8fa8f62 3162 sport, ssh, &ssh->cfg);
6ee9b735 3163 logeventf(ssh, "Local port %.*s%.*s%.*s%.*s%d%.*s"
3164 " forwarding to %s:%.*s%.*s%d%.*s",
3165 (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
3166 (int)(*saddr?1:0), ":",
57356d63 3167 (int)(sserv ? strlen(sports) : 0), sports,
3168 sserv, "(", sport, sserv, ")",
3169 host,
3170 (int)(dserv ? strlen(dports) : 0), dports,
3171 dserv, "(", dport, dserv, ")");
d74d141c 3172 } else {
3173 struct ssh_rportfwd *pf;
3174 pf = smalloc(sizeof(*pf));
bc240b21 3175 strcpy(pf->dhost, host);
3176 pf->dport = dport;
6ee9b735 3177 if (saddr) {
3178 logeventf(ssh,
3179 "SSH1 cannot handle source address spec \"%s:%d\"; ignoring",
3180 saddr, sport);
3181 }
51470298 3182 if (add234(ssh->rportfwds, pf) != pf) {
57356d63 3183 logeventf(ssh,
3184 "Duplicate remote port forwarding to %s:%d",
3185 host, dport);
bc240b21 3186 sfree(pf);
d74d141c 3187 } else {
57356d63 3188 logeventf(ssh, "Requesting remote port %.*s%.*s%d%.*s"
3189 " forward to %s:%.*s%.*s%d%.*s",
3190 (int)(sserv ? strlen(sports) : 0), sports,
3191 sserv, "(", sport, sserv, ")",
3192 host,
3193 (int)(dserv ? strlen(dports) : 0), dports,
3194 dserv, "(", dport, dserv, ")");
51470298 3195 send_packet(ssh, SSH1_CMSG_PORT_FORWARD_REQUEST,
d74d141c 3196 PKT_INT, sport,
3197 PKT_STR, host,
3198 PKT_INT, dport,
3199 PKT_END);
9bf696b1 3200 do {
3201 crReturnV;
3202 } while (!ispkt);
51470298 3203 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3204 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
a8327734 3205 bombout((ssh,"Protocol confusion"));
9bf696b1 3206 crReturnV;
51470298 3207 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
3208 c_write_str(ssh, "Server refused port"
3209 " forwarding\r\n");
9bf696b1 3210 }
3211 logevent("Remote port forwarding enabled");
d74d141c 3212 }
3213 }
3214 }
3215 }
3216 }
3217
86916870 3218 if (!ssh->cfg.nopty) {
51470298 3219 send_packet(ssh, SSH1_CMSG_REQUEST_PTY,
86916870 3220 PKT_STR, ssh->cfg.termtype,
51470298 3221 PKT_INT, ssh->term_height,
3222 PKT_INT, ssh->term_width,
32874aea 3223 PKT_INT, 0, PKT_INT, 0, PKT_CHAR, 0, PKT_END);
51470298 3224 ssh->state = SSH_STATE_INTERMED;
32874aea 3225 do {
3226 crReturnV;
3227 } while (!ispkt);
51470298 3228 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3229 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
a8327734 3230 bombout((ssh,"Protocol confusion"));
32874aea 3231 crReturnV;
51470298 3232 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
3233 c_write_str(ssh, "Server refused to allocate pty\r\n");
3234 ssh->editing = ssh->echoing = 1;
32874aea 3235 }
c5e9c988 3236 logevent("Allocated pty");
0965bee0 3237 } else {
51470298 3238 ssh->editing = ssh->echoing = 1;
374330e2 3239 }
3240
86916870 3241 if (ssh->cfg.compression) {
51470298 3242 send_packet(ssh, SSH1_CMSG_REQUEST_COMPRESSION, PKT_INT, 6, PKT_END);
32874aea 3243 do {
3244 crReturnV;
3245 } while (!ispkt);
51470298 3246 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3247 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
a8327734 3248 bombout((ssh,"Protocol confusion"));
32874aea 3249 crReturnV;
51470298 3250 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
3251 c_write_str(ssh, "Server refused to compress\r\n");
32874aea 3252 }
4ba9b64b 3253 logevent("Started compression");
51470298 3254 ssh->v1_compressing = TRUE;
5366aed8 3255 ssh->cs_comp_ctx = zlib_compress_init();
3256 logevent("Initialised zlib (RFC1950) compression");
3257 ssh->sc_comp_ctx = zlib_decompress_init();
3258 logevent("Initialised zlib (RFC1950) decompression");
4ba9b64b 3259 }
3260
fd5e5847 3261 /*
3262 * Start the shell or command.
3263 *
3264 * Special case: if the first-choice command is an SSH2
3265 * subsystem (hence not usable here) and the second choice
3266 * exists, we fall straight back to that.
3267 */
3268 {
86916870 3269 char *cmd = ssh->cfg.remote_cmd_ptr;
fd5e5847 3270
86916870 3271 if (ssh->cfg.ssh_subsys && ssh->cfg.remote_cmd_ptr2) {
3272 cmd = ssh->cfg.remote_cmd_ptr2;
51470298 3273 ssh->fallback_cmd = TRUE;
fd5e5847 3274 }
3275 if (*cmd)
51470298 3276 send_packet(ssh, SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END);
fd5e5847 3277 else
51470298 3278 send_packet(ssh, SSH1_CMSG_EXEC_SHELL, PKT_END);
fd5e5847 3279 logevent("Started session");
3280 }
374330e2 3281
51470298 3282 ssh->state = SSH_STATE_SESSION;
3283 if (ssh->size_needed)
3284 ssh_size(ssh, ssh->term_width, ssh->term_height);
3285 if (ssh->eof_needed)
3286 ssh_special(ssh, TS_EOF);
374330e2 3287
b9d7bcad 3288 if (ssh->ldisc)
3289 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
51470298 3290 ssh->send_ok = 1;
3291 ssh->channels = newtree234(ssh_channelcmp);
374330e2 3292 while (1) {
3293 crReturnV;
3294 if (ispkt) {
51470298 3295 if (ssh->pktin.type == SSH1_SMSG_STDOUT_DATA ||
3296 ssh->pktin.type == SSH1_SMSG_STDERR_DATA) {
3297 long len = GET_32BIT(ssh->pktin.body);
5471d09a 3298 int bufsize =
51470298 3299 from_backend(ssh->frontend,
3300 ssh->pktin.type == SSH1_SMSG_STDERR_DATA,
d8baa528 3301 (char *)(ssh->pktin.body) + 4, len);
51470298 3302 if (!ssh->v1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
3303 ssh->v1_stdout_throttling = 1;
3304 ssh1_throttle(ssh, +1);
5471d09a 3305 }
51470298 3306 } else if (ssh->pktin.type == SSH1_MSG_DISCONNECT) {
3307 ssh->state = SSH_STATE_CLOSED;
c5e9c988 3308 logevent("Received disconnect request");
32874aea 3309 crReturnV;
51470298 3310 } else if (ssh->pktin.type == SSH1_SMSG_X11_OPEN) {
32874aea 3311 /* Remote side is trying to open a channel to talk to our
3312 * X-Server. Give them back a local channel number. */
3313 struct ssh_channel *c;
9c964e85 3314
3315 logevent("Received X11 connect request");
3316 /* Refuse if X11 forwarding is disabled. */
51470298 3317 if (!ssh->X11_fwd_enabled) {
3318 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
3319 PKT_INT, GET_32BIT(ssh->pktin.body), PKT_END);
9c964e85 3320 logevent("Rejected X11 connect request");
3321 } else {
9c964e85 3322 c = smalloc(sizeof(struct ssh_channel));
51470298 3323 c->ssh = ssh;
9c964e85 3324
86916870 3325 if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
e8fa8f62 3326 ssh->x11auth, NULL, -1, &ssh->cfg) != NULL) {
32874aea 3327 logevent("opening X11 forward connection failed");
3328 sfree(c);
51470298 3329 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
3330 PKT_INT, GET_32BIT(ssh->pktin.body),
32874aea 3331 PKT_END);
9c964e85 3332 } else {
32874aea 3333 logevent
3334 ("opening X11 forward connection succeeded");
51470298 3335 c->remoteid = GET_32BIT(ssh->pktin.body);
3336 c->localid = alloc_channel_id(ssh);
32874aea 3337 c->closes = 0;
5471d09a 3338 c->v.v1.throttling = 0;
32874aea 3339 c->type = CHAN_X11; /* identify channel type */
51470298 3340 add234(ssh->channels, c);
3341 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
32874aea 3342 PKT_INT, c->remoteid, PKT_INT,
3343 c->localid, PKT_END);
3344 logevent("Opened X11 forward channel");
9c964e85 3345 }
3346 }
51470298 3347 } else if (ssh->pktin.type == SSH1_SMSG_AGENT_OPEN) {
32874aea 3348 /* Remote side is trying to open a channel to talk to our
3349 * agent. Give them back a local channel number. */
3350 struct ssh_channel *c;
db7d555c 3351
3352 /* Refuse if agent forwarding is disabled. */
51470298 3353 if (!ssh->agentfwd_enabled) {
3354 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
3355 PKT_INT, GET_32BIT(ssh->pktin.body), PKT_END);
db7d555c 3356 } else {
dcbde236 3357 c = smalloc(sizeof(struct ssh_channel));
51470298 3358 c->ssh = ssh;
3359 c->remoteid = GET_32BIT(ssh->pktin.body);
3360 c->localid = alloc_channel_id(ssh);
db7d555c 3361 c->closes = 0;
5471d09a 3362 c->v.v1.throttling = 0;
32874aea 3363 c->type = CHAN_AGENT; /* identify channel type */
db7d555c 3364 c->u.a.lensofar = 0;
51470298 3365 add234(ssh->channels, c);
3366 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
db7d555c 3367 PKT_INT, c->remoteid, PKT_INT, c->localid,
3368 PKT_END);
3369 }
51470298 3370 } else if (ssh->pktin.type == SSH1_MSG_PORT_OPEN) {
d74d141c 3371 /* Remote side is trying to open a channel to talk to a
3372 * forwarded port. Give them back a local channel number. */
3373 struct ssh_channel *c;
3374 struct ssh_rportfwd pf;
3375 int hostsize, port;
3376 char host[256], buf[1024];
3377 char *p, *h, *e;
3378 c = smalloc(sizeof(struct ssh_channel));
51470298 3379 c->ssh = ssh;
d74d141c 3380
51470298 3381 hostsize = GET_32BIT(ssh->pktin.body+4);
d8baa528 3382 for (h = host, p = (char *)(ssh->pktin.body+8);
3383 hostsize != 0; hostsize--) {
d74d141c 3384 if (h+1 < host+sizeof(host))
3385 *h++ = *p;
95bc8819 3386 p++;
d74d141c 3387 }
3388 *h = 0;
3389 port = GET_32BIT(p);
3390
bc240b21 3391 strcpy(pf.dhost, host);
3392 pf.dport = port;
d74d141c 3393
51470298 3394 if (find234(ssh->rportfwds, &pf, NULL) == NULL) {
d74d141c 3395 sprintf(buf, "Rejected remote port open request for %s:%d",
3396 host, port);
3397 logevent(buf);
51470298 3398 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
3399 PKT_INT, GET_32BIT(ssh->pktin.body), PKT_END);
d74d141c 3400 } else {
3401 sprintf(buf, "Received remote port open request for %s:%d",
3402 host, port);
3403 logevent(buf);
e8fa8f62 3404 e = pfd_newconnect(&c->u.pfd.s, host, port, c, &ssh->cfg);
d74d141c 3405 if (e != NULL) {
3406 char buf[256];
3407 sprintf(buf, "Port open failed: %s", e);
3408 logevent(buf);
3409 sfree(c);
51470298 3410 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
3411 PKT_INT, GET_32BIT(ssh->pktin.body),
d74d141c 3412 PKT_END);
3413 } else {
51470298 3414 c->remoteid = GET_32BIT(ssh->pktin.body);
3415 c->localid = alloc_channel_id(ssh);
d74d141c 3416 c->closes = 0;
5471d09a 3417 c->v.v1.throttling = 0;
d74d141c 3418 c->type = CHAN_SOCKDATA; /* identify channel type */
51470298 3419 add234(ssh->channels, c);
3420 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
d74d141c 3421 PKT_INT, c->remoteid, PKT_INT,
3422 c->localid, PKT_END);
3423 logevent("Forwarded port opened successfully");
3424 }
3425 }
3426
51470298 3427 } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_OPEN_CONFIRMATION) {
3428 unsigned int remoteid = GET_32BIT(ssh->pktin.body);
3429 unsigned int localid = GET_32BIT(ssh->pktin.body+4);
bc240b21 3430 struct ssh_channel *c;
3431
51470298 3432 c = find234(ssh->channels, &remoteid, ssh_channelfind);
bc240b21 3433 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
3434 c->remoteid = localid;
3435 c->type = CHAN_SOCKDATA;
7781f316 3436 c->v.v1.throttling = 0;
bc240b21 3437 pfd_confirm(c->u.pfd.s);
3438 }
d74d141c 3439
4ed34d25 3440 if (c && c->closes) {
3441 /*
3442 * We have a pending close on this channel,
3443 * which we decided on before the server acked
3444 * the channel open. So now we know the
3445 * remoteid, we can close it again.
3446 */
51470298 3447 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE,
3448 PKT_INT, c->remoteid, PKT_END);
4ed34d25 3449 }
3450
51470298 3451 } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_OPEN_FAILURE) {
3452 unsigned int remoteid = GET_32BIT(ssh->pktin.body);
724cface 3453 struct ssh_channel *c;
3454
51470298 3455 c = find234(ssh->channels, &remoteid, ssh_channelfind);
724cface 3456 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
3457 logevent("Forwarded connection refused by server");
3458 pfd_close(c->u.pfd.s);
51470298 3459 del234(ssh->channels, c);
724cface 3460 sfree(c);
3461 }
3462
51470298 3463 } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE ||
3464 ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) {
32874aea 3465 /* Remote side closes a channel. */
51470298 3466 unsigned i = GET_32BIT(ssh->pktin.body);
32874aea 3467 struct ssh_channel *c;
51470298 3468 c = find234(ssh->channels, &i, ssh_channelfind);
d0d844c1 3469 if (c && ((int)c->remoteid) != -1) {
32874aea 3470 int closetype;
3471 closetype =
51470298 3472 (ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
0357890f 3473
783415f8 3474 if ((c->closes == 0) && (c->type == CHAN_X11)) {
d74d141c 3475 logevent("Forwarded X11 connection terminated");
9c964e85 3476 assert(c->u.x11.s != NULL);
3477 x11_close(c->u.x11.s);
3478 c->u.x11.s = NULL;
3479 }
d74d141c 3480 if ((c->closes == 0) && (c->type == CHAN_SOCKDATA)) {
3481 logevent("Forwarded port closed");
3482 assert(c->u.pfd.s != NULL);
3483 pfd_close(c->u.pfd.s);
3484 c->u.pfd.s = NULL;
3485 }
0357890f 3486
3487 c->closes |= (closetype << 2); /* seen this message */
3488 if (!(c->closes & closetype)) {
51470298 3489 send_packet(ssh, ssh->pktin.type, PKT_INT, c->remoteid,
0357890f 3490 PKT_END);
3491 c->closes |= closetype; /* sent it too */
3492 }
3493
3494 if (c->closes == 15) {
51470298 3495 del234(ssh->channels, c);
32874aea 3496 sfree(c);
3497 }
d0d844c1 3498 } else {
a8327734 3499 bombout((ssh,"Received CHANNEL_CLOSE%s for %s channel %d\n",
51470298 3500 ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE ? "" :
d0d844c1 3501 "_CONFIRMATION", c ? "half-open" : "nonexistent",
3502 i));
32874aea 3503 }
51470298 3504 } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_DATA) {
32874aea 3505 /* Data sent down one of our channels. */
51470298 3506 int i = GET_32BIT(ssh->pktin.body);
3507 int len = GET_32BIT(ssh->pktin.body + 4);
3508 unsigned char *p = ssh->pktin.body + 8;
32874aea 3509 struct ssh_channel *c;
51470298 3510 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 3511 if (c) {
5471d09a 3512 int bufsize;
32874aea 3513 switch (c->type) {
3514 case CHAN_X11:
d8baa528 3515 bufsize = x11_send(c->u.x11.s, (char *)p, len);
9c964e85 3516 break;
d74d141c 3517 case CHAN_SOCKDATA:
d8baa528 3518 bufsize = pfd_send(c->u.pfd.s, (char *)p, len);
bc240b21 3519 break;
32874aea 3520 case CHAN_AGENT:
3521 /* Data for an agent message. Buffer it. */
3522 while (len > 0) {
3523 if (c->u.a.lensofar < 4) {
3524 int l = min(4 - c->u.a.lensofar, len);
3525 memcpy(c->u.a.msglen + c->u.a.lensofar, p,
3526 l);
3527 p += l;
3528 len -= l;
3529 c->u.a.lensofar += l;
3530 }
3531 if (c->u.a.lensofar == 4) {
3532 c->u.a.totallen =
3533 4 + GET_32BIT(c->u.a.msglen);
3534 c->u.a.message = smalloc(c->u.a.totallen);
3535 memcpy(c->u.a.message, c->u.a.msglen, 4);
3536 }
3537 if (c->u.a.lensofar >= 4 && len > 0) {
3538 int l =
3539 min(c->u.a.totallen - c->u.a.lensofar,
3540 len);
3541 memcpy(c->u.a.message + c->u.a.lensofar, p,
3542 l);
3543 p += l;
3544 len -= l;
3545 c->u.a.lensofar += l;
3546 }
3547 if (c->u.a.lensofar == c->u.a.totallen) {
3548 void *reply, *sentreply;
3549 int replylen;
3550 agent_query(c->u.a.message,
3551 c->u.a.totallen, &reply,
3552 &replylen);
3553 if (reply)
3554 sentreply = reply;
3555 else {
3556 /* Fake SSH_AGENT_FAILURE. */
3557 sentreply = "\0\0\0\1\5";
3558 replylen = 5;
3559 }
51470298 3560 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
32874aea 3561 PKT_INT, c->remoteid,
3562 PKT_INT, replylen,
3563 PKT_DATA, sentreply, replylen,
3564 PKT_END);
3565 if (reply)
3566 sfree(reply);
3567 sfree(c->u.a.message);
3568 c->u.a.lensofar = 0;
3569 }
3570 }
5471d09a 3571 bufsize = 0; /* agent channels never back up */
32874aea 3572 break;
3573 }
90347b95 3574 if (!c->v.v1.throttling && bufsize > SSH1_BUFFER_LIMIT) {
5471d09a 3575 c->v.v1.throttling = 1;
51470298 3576 ssh1_throttle(ssh, +1);
5471d09a 3577 }
32874aea 3578 }
51470298 3579 } else if (ssh->pktin.type == SSH1_SMSG_SUCCESS) {
972a41c8 3580 /* may be from EXEC_SHELL on some servers */
51470298 3581 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
972a41c8 3582 /* may be from EXEC_SHELL on some servers
374330e2 3583 * if no pty is available or in other odd cases. Ignore */
51470298 3584 } else if (ssh->pktin.type == SSH1_SMSG_EXIT_STATUS) {
d8d6c7e5 3585 char buf[100];
51470298 3586 ssh->exitcode = GET_32BIT(ssh->pktin.body);
d8d6c7e5 3587 sprintf(buf, "Server sent command exit status %d",
51470298 3588 ssh->exitcode);
d8d6c7e5 3589 logevent(buf);
51470298 3590 send_packet(ssh, SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
4252c9cc 3591 /*
3592 * In case `helpful' firewalls or proxies tack
3593 * extra human-readable text on the end of the
3594 * session which we might mistake for another
3595 * encrypted packet, we close the session once
3596 * we've sent EXIT_CONFIRMATION.
3597 */
51470298 3598 ssh->state = SSH_STATE_CLOSED;
4252c9cc 3599 crReturnV;
374330e2 3600 } else {
a8327734 3601 bombout((ssh,"Strange packet received: type %d", ssh->pktin.type));
32874aea 3602 crReturnV;
374330e2 3603 }
3604 } else {
8df7a775 3605 while (inlen > 0) {
3606 int len = min(inlen, 512);
51470298 3607 send_packet(ssh, SSH1_CMSG_STDIN_DATA,
8df7a775 3608 PKT_INT, len, PKT_DATA, in, len, PKT_END);
3609 in += len;
3610 inlen -= len;
3611 }
374330e2 3612 }
3613 }
3614
3615 crFinishV;
3616}
3617
3618/*
e5574168 3619 * Utility routine for decoding comma-separated strings in KEXINIT.
3620 */
32874aea 3621static int in_commasep_string(char *needle, char *haystack, int haylen)
3622{
57356d63 3623 int needlen;
3624 if (!needle || !haystack) /* protect against null pointers */
3625 return 0;
3626 needlen = strlen(needle);
e5574168 3627 while (1) {
32874aea 3628 /*
3629 * Is it at the start of the string?
3630 */
3631 if (haylen >= needlen && /* haystack is long enough */
3632 !memcmp(needle, haystack, needlen) && /* initial match */
3633 (haylen == needlen || haystack[needlen] == ',')
3634 /* either , or EOS follows */
3635 )
3636 return 1;
3637 /*
3638 * If not, search for the next comma and resume after that.
3639 * If no comma found, terminate.
3640 */
3641 while (haylen > 0 && *haystack != ',')
3642 haylen--, haystack++;
3643 if (haylen == 0)
3644 return 0;
3645 haylen--, haystack++; /* skip over comma itself */
e5574168 3646 }
3647}
3648
3649/*
d39f364a 3650 * SSH2 key creation method.
3651 */
d8baa528 3652static void ssh2_mkkey(Ssh ssh, Bignum K, unsigned char *H,
3653 unsigned char *sessid, char chr,
3654 unsigned char *keyspace)
32874aea 3655{
d39f364a 3656 SHA_State s;
3657 /* First 20 bytes. */
3658 SHA_Init(&s);
51470298 3659 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
088bde77 3660 sha_mpint(&s, K);
d39f364a 3661 SHA_Bytes(&s, H, 20);
3662 SHA_Bytes(&s, &chr, 1);
5e0d7cb8 3663 SHA_Bytes(&s, sessid, 20);
d39f364a 3664 SHA_Final(&s, keyspace);
3665 /* Next 20 bytes. */
3666 SHA_Init(&s);
51470298 3667 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
088bde77 3668 sha_mpint(&s, K);
d39f364a 3669 SHA_Bytes(&s, H, 20);
3670 SHA_Bytes(&s, keyspace, 20);
32874aea 3671 SHA_Final(&s, keyspace + 20);
d39f364a 3672}
3673
3674/*
7cca0d81 3675 * Handle the SSH2 transport layer.
e5574168 3676 */
51470298 3677static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
e5574168 3678{
51470298 3679 struct do_ssh2_transport_state {
3680 int nbits, pbits, warn;
3681 Bignum p, g, e, f, K;
3682 int kex_init_value, kex_reply_value;
3683 const struct ssh_mac **maclist;
3684 int nmacs;
3685 const struct ssh2_cipher *cscipher_tobe;
3686 const struct ssh2_cipher *sccipher_tobe;
3687 const struct ssh_mac *csmac_tobe;
3688 const struct ssh_mac *scmac_tobe;
3689 const struct ssh_compress *cscomp_tobe;
3690 const struct ssh_compress *sccomp_tobe;
3691 char *hostkeydata, *sigdata, *keystr, *fingerprint;
3692 int hostkeylen, siglen;
3693 void *hkey; /* actual host key */
3694 unsigned char exchange_hash[20];
3695 int n_preferred_ciphers;
3696 const struct ssh2_ciphers *preferred_ciphers[CIPHER_MAX];
3697 const struct ssh_compress *preferred_comp;
3698 int first_kex;
3699 };
3700 crState(do_ssh2_transport_state);
3701
3702 crBegin(ssh->do_ssh2_transport_crstate);
3703
3704 s->cscipher_tobe = s->sccipher_tobe = NULL;
3705 s->csmac_tobe = s->scmac_tobe = NULL;
3706 s->cscomp_tobe = s->sccomp_tobe = NULL;
3707
7cca0d81 3708 random_init();
51470298 3709 s->first_kex = 1;
e5574168 3710
51470298 3711 {
3712 int i;
3713 /*
3714 * Set up the preferred ciphers. (NULL => warn below here)
3715 */
3716 s->n_preferred_ciphers = 0;
3717 for (i = 0; i < CIPHER_MAX; i++) {
86916870 3718 switch (ssh->cfg.ssh_cipherlist[i]) {
51470298 3719 case CIPHER_BLOWFISH:
3720 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_blowfish;
3721 break;
3722 case CIPHER_DES:
86916870 3723 if (ssh->cfg.ssh2_des_cbc) {
51470298 3724 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_des;
3725 }
3726 break;
3727 case CIPHER_3DES:
3728 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_3des;
3729 break;
3730 case CIPHER_AES:
3731 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_aes;
3732 break;
3733 case CIPHER_WARN:
3734 /* Flag for later. Don't bother if it's the last in
3735 * the list. */
3736 if (i < CIPHER_MAX - 1) {
3737 s->preferred_ciphers[s->n_preferred_ciphers++] = NULL;
3738 }
3739 break;
ca20bfcf 3740 }
ca20bfcf 3741 }
5e8358ad 3742 }
ca20bfcf 3743
3744 /*
3745 * Set up preferred compression.
3746 */
86916870 3747 if (ssh->cfg.compression)
51470298 3748 s->preferred_comp = &ssh_zlib;
4ba9b64b 3749 else
51470298 3750 s->preferred_comp = &ssh_comp_none;
5e8358ad 3751
7591b9ff 3752 /*
3753 * Be prepared to work around the buggy MAC problem.
3754 */
51470298 3755 if (ssh->remote_bugs & BUG_SSH2_HMAC)
3756 s->maclist = buggymacs, s->nmacs = lenof(buggymacs);
7591b9ff 3757 else
51470298 3758 s->maclist = macs, s->nmacs = lenof(macs);
7591b9ff 3759
32874aea 3760 begin_key_exchange:
51470298 3761 {
3762 int i, j, cipherstr_started;
3763
3764 /*
3765 * Construct and send our key exchange packet.
3766 */
3767 ssh2_pkt_init(ssh, SSH2_MSG_KEXINIT);
3768 for (i = 0; i < 16; i++)
3769 ssh2_pkt_addbyte(ssh, (unsigned char) random_byte());
3770 /* List key exchange algorithms. */
3771 ssh2_pkt_addstring_start(ssh);
3772 for (i = 0; i < lenof(kex_algs); i++) {
3773 if (kex_algs[i] == &ssh_diffiehellman_gex &&
3774 (ssh->remote_bugs & BUG_SSH2_DH_GEX))
3775 continue;
3776 ssh2_pkt_addstring_str(ssh, kex_algs[i]->name);
3777 if (i < lenof(kex_algs) - 1)
3778 ssh2_pkt_addstring_str(ssh, ",");
32874aea 3779 }
51470298 3780 /* List server host key algorithms. */
3781 ssh2_pkt_addstring_start(ssh);
3782 for (i = 0; i < lenof(hostkey_algs); i++) {
3783 ssh2_pkt_addstring_str(ssh, hostkey_algs[i]->name);
3784 if (i < lenof(hostkey_algs) - 1)
3785 ssh2_pkt_addstring_str(ssh, ",");
32874aea 3786 }
51470298 3787 /* List client->server encryption algorithms. */
3788 ssh2_pkt_addstring_start(ssh);
3789 cipherstr_started = 0;
3790 for (i = 0; i < s->n_preferred_ciphers; i++) {
3791 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
3792 if (!c) continue; /* warning flag */
3793 for (j = 0; j < c->nciphers; j++) {
3794 if (cipherstr_started)
3795 ssh2_pkt_addstring_str(ssh, ",");
3796 ssh2_pkt_addstring_str(ssh, c->list[j]->name);
3797 cipherstr_started = 1;
3798 }
3799 }
3800 /* List server->client encryption algorithms. */
3801 ssh2_pkt_addstring_start(ssh);
3802 cipherstr_started = 0;
3803 for (i = 0; i < s->n_preferred_ciphers; i++) {
3804 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
3805 if (!c) continue; /* warning flag */
3806 for (j = 0; j < c->nciphers; j++) {
3807 if (cipherstr_started)
3808 ssh2_pkt_addstring_str(ssh, ",");
3809 ssh2_pkt_addstring_str(ssh, c->list[j]->name);
3810 cipherstr_started = 1;
3811 }
3812 }
3813 /* List client->server MAC algorithms. */
3814 ssh2_pkt_addstring_start(ssh);
3815 for (i = 0; i < s->nmacs; i++) {
3816 ssh2_pkt_addstring_str(ssh, s->maclist[i]->name);
3817 if (i < s->nmacs - 1)
3818 ssh2_pkt_addstring_str(ssh, ",");
3819 }
3820 /* List server->client MAC algorithms. */
3821 ssh2_pkt_addstring_start(ssh);
3822 for (i = 0; i < s->nmacs; i++) {
3823 ssh2_pkt_addstring_str(ssh, s->maclist[i]->name);
3824 if (i < s->nmacs - 1)
3825 ssh2_pkt_addstring_str(ssh, ",");
3826 }
3827 /* List client->server compression algorithms. */
3828 ssh2_pkt_addstring_start(ssh);
3829 for (i = 0; i < lenof(compressions) + 1; i++) {
3830 const struct ssh_compress *c =
3831 i == 0 ? s->preferred_comp : compressions[i - 1];
3832 ssh2_pkt_addstring_str(ssh, c->name);
3833 if (i < lenof(compressions))
3834 ssh2_pkt_addstring_str(ssh, ",");
3835 }
3836 /* List server->client compression algorithms. */
3837 ssh2_pkt_addstring_start(ssh);
3838 for (i = 0; i < lenof(compressions) + 1; i++) {
3839 const struct ssh_compress *c =
3840 i == 0 ? s->preferred_comp : compressions[i - 1];
3841 ssh2_pkt_addstring_str(ssh, c->name);
3842 if (i < lenof(compressions))
3843 ssh2_pkt_addstring_str(ssh, ",");
3844 }
3845 /* List client->server languages. Empty list. */
3846 ssh2_pkt_addstring_start(ssh);
3847 /* List server->client languages. Empty list. */
3848 ssh2_pkt_addstring_start(ssh);
3849 /* First KEX packet does _not_ follow, because we're not that brave. */
3850 ssh2_pkt_addbool(ssh, FALSE);
3851 /* Reserved. */
3852 ssh2_pkt_adduint32(ssh, 0);
e5574168 3853 }
0db56f73 3854
51470298 3855 ssh->exhash = ssh->exhashbase;
3856 sha_string(&ssh->exhash, ssh->pktout.data + 5, ssh->pktout.length - 5);
0db56f73 3857
51470298 3858 ssh2_pkt_send(ssh);
e5574168 3859
32874aea 3860 if (!ispkt)
3861 crWaitUntil(ispkt);
57356d63 3862 if (ssh->pktin.length > 5)
3863 sha_string(&ssh->exhash, ssh->pktin.data + 5, ssh->pktin.length - 5);
e5574168 3864
3865 /*
3866 * Now examine the other side's KEXINIT to see what we're up
3867 * to.
3868 */
51470298 3869 {
3870 char *str;
3871 int i, j, len;
3872
3873 if (ssh->pktin.type != SSH2_MSG_KEXINIT) {
a8327734 3874 bombout((ssh,"expected key exchange packet from server"));
51470298 3875 crReturn(0);
32874aea 3876 }
51470298 3877 ssh->kex = NULL;
3878 ssh->hostkey = NULL;
3879 s->cscipher_tobe = NULL;
3880 s->sccipher_tobe = NULL;
3881 s->csmac_tobe = NULL;
3882 s->scmac_tobe = NULL;
3883 s->cscomp_tobe = NULL;
3884 s->sccomp_tobe = NULL;
3885 ssh->pktin.savedpos += 16; /* skip garbage cookie */
3886 ssh2_pkt_getstring(ssh, &str, &len); /* key exchange algorithms */
3887 for (i = 0; i < lenof(kex_algs); i++) {
3888 if (kex_algs[i] == &ssh_diffiehellman_gex &&
3889 (ssh->remote_bugs & BUG_SSH2_DH_GEX))
3890 continue;
3891 if (in_commasep_string(kex_algs[i]->name, str, len)) {
3892 ssh->kex = kex_algs[i];
3893 break;
3894 }
32874aea 3895 }
51470298 3896 ssh2_pkt_getstring(ssh, &str, &len); /* host key algorithms */
3897 for (i = 0; i < lenof(hostkey_algs); i++) {
3898 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
3899 ssh->hostkey = hostkey_algs[i];
3900 break;
3901 }
3902 }
3903 ssh2_pkt_getstring(ssh, &str, &len); /* client->server cipher */
3904 s->warn = 0;
3905 for (i = 0; i < s->n_preferred_ciphers; i++) {
3906 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
3907 if (!c) {
3908 s->warn = 1;
3909 } else {
3910 for (j = 0; j < c->nciphers; j++) {
3911 if (in_commasep_string(c->list[j]->name, str, len)) {
3912 s->cscipher_tobe = c->list[j];
3913 break;
3914 }
ca20bfcf 3915 }
32874aea 3916 }
51470298 3917 if (s->cscipher_tobe) {
3918 if (s->warn)
a8327734 3919 askcipher(ssh->frontend, s->cscipher_tobe->name, 1);
51470298 3920 break;
3921 }
32874aea 3922 }
51470298 3923 if (!s->cscipher_tobe) {
57356d63 3924 bombout((ssh,"Couldn't agree a client-to-server cipher (available: %s)",
3925 str ? str : "(null)"));
51470298 3926 crReturn(0);
ca20bfcf 3927 }
0ef8f407 3928
51470298 3929 ssh2_pkt_getstring(ssh, &str, &len); /* server->client cipher */
3930 s->warn = 0;
3931 for (i = 0; i < s->n_preferred_ciphers; i++) {
3932 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
3933 if (!c) {
3934 s->warn = 1;
3935 } else {
3936 for (j = 0; j < c->nciphers; j++) {
3937 if (in_commasep_string(c->list[j]->name, str, len)) {
3938 s->sccipher_tobe = c->list[j];
3939 break;
3940 }
ca20bfcf 3941 }
32874aea 3942 }
51470298 3943 if (s->sccipher_tobe) {
3944 if (s->warn)
a8327734 3945 askcipher(ssh->frontend, s->sccipher_tobe->name, 2);
51470298 3946 break;
3947 }
32874aea 3948 }
51470298 3949 if (!s->sccipher_tobe) {
57356d63 3950 bombout((ssh,"Couldn't agree a server-to-client cipher (available: %s)",
3951 str ? str : "(null)"));
51470298 3952 crReturn(0);
ca20bfcf 3953 }
0ef8f407 3954
51470298 3955 ssh2_pkt_getstring(ssh, &str, &len); /* client->server mac */
3956 for (i = 0; i < s->nmacs; i++) {
3957 if (in_commasep_string(s->maclist[i]->name, str, len)) {
3958 s->csmac_tobe = s->maclist[i];
3959 break;
3960 }
32874aea 3961 }
51470298 3962 ssh2_pkt_getstring(ssh, &str, &len); /* server->client mac */
3963 for (i = 0; i < s->nmacs; i++) {
3964 if (in_commasep_string(s->maclist[i]->name, str, len)) {
3965 s->scmac_tobe = s->maclist[i];
3966 break;
3967 }
32874aea 3968 }
51470298 3969 ssh2_pkt_getstring(ssh, &str, &len); /* client->server compression */
3970 for (i = 0; i < lenof(compressions) + 1; i++) {
3971 const struct ssh_compress *c =
3972 i == 0 ? s->preferred_comp : compressions[i - 1];
3973 if (in_commasep_string(c->name, str, len)) {
3974 s->cscomp_tobe = c;
3975 break;
3976 }
32874aea 3977 }
51470298 3978 ssh2_pkt_getstring(ssh, &str, &len); /* server->client compression */
3979 for (i = 0; i < lenof(compressions) + 1; i++) {
3980 const struct ssh_compress *c =
3981 i == 0 ? s->preferred_comp : compressions[i - 1];
3982 if (in_commasep_string(c->name, str, len)) {
3983 s->sccomp_tobe = c;
3984 break;
3985 }
32874aea 3986 }
e5574168 3987 }
e5574168 3988
3989 /*
7bd5a860 3990 * Work out the number of bits of key we will need from the key
3991 * exchange. We start with the maximum key length of either
3992 * cipher...
3993 */
3994 {
32874aea 3995 int csbits, scbits;
7bd5a860 3996
51470298 3997 csbits = s->cscipher_tobe->keylen;
3998 scbits = s->sccipher_tobe->keylen;
3999 s->nbits = (csbits > scbits ? csbits : scbits);
7bd5a860 4000 }
4001 /* The keys only have 160-bit entropy, since they're based on
4002 * a SHA-1 hash. So cap the key size at 160 bits. */
51470298 4003 if (s->nbits > 160)
4004 s->nbits = 160;
7bd5a860 4005
4006 /*
a92dd380 4007 * If we're doing Diffie-Hellman group exchange, start by
4008 * requesting a group.
e5574168 4009 */
51470298 4010 if (ssh->kex == &ssh_diffiehellman_gex) {
32874aea 4011 logevent("Doing Diffie-Hellman group exchange");
51470298 4012 ssh->pkt_ctx |= SSH2_PKTCTX_DHGEX;
32874aea 4013 /*
4014 * Work out how big a DH group we will need to allow that
4015 * much data.
7bd5a860 4016 */
51470298 4017 s->pbits = 512 << ((s->nbits - 1) / 64);
4018 ssh2_pkt_init(ssh, SSH2_MSG_KEX_DH_GEX_REQUEST);
4019 ssh2_pkt_adduint32(ssh, s->pbits);
4020 ssh2_pkt_send(ssh);
32874aea 4021
4022 crWaitUntil(ispkt);
51470298 4023 if (ssh->pktin.type != SSH2_MSG_KEX_DH_GEX_GROUP) {
a8327734 4024 bombout((ssh,"expected key exchange group packet from server"));
32874aea 4025 crReturn(0);
4026 }
51470298 4027 s->p = ssh2_pkt_getmp(ssh);
4028 s->g = ssh2_pkt_getmp(ssh);
27cd7fc2 4029 ssh->kex_ctx = dh_setup_group(s->p, s->g);
51470298 4030 s->kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
4031 s->kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY;
a92dd380 4032 } else {
51470298 4033 ssh->pkt_ctx |= SSH2_PKTCTX_DHGROUP1;
27cd7fc2 4034 ssh->kex_ctx = dh_setup_group1();
51470298 4035 s->kex_init_value = SSH2_MSG_KEXDH_INIT;
4036 s->kex_reply_value = SSH2_MSG_KEXDH_REPLY;
8d5de777 4037 }
e5574168 4038
a92dd380 4039 logevent("Doing Diffie-Hellman key exchange");
e5574168 4040 /*
a92dd380 4041 * Now generate and send e for Diffie-Hellman.
e5574168 4042 */
27cd7fc2 4043 s->e = dh_create_e(ssh->kex_ctx, s->nbits * 2);
51470298 4044 ssh2_pkt_init(ssh, s->kex_init_value);
4045 ssh2_pkt_addmp(ssh, s->e);
4046 ssh2_pkt_send(ssh);
e5574168 4047
4048 crWaitUntil(ispkt);
51470298 4049 if (ssh->pktin.type != s->kex_reply_value) {
a8327734 4050 bombout((ssh,"expected key exchange reply packet from server"));
32874aea 4051 crReturn(0);
7cca0d81 4052 }
51470298 4053 ssh2_pkt_getstring(ssh, &s->hostkeydata, &s->hostkeylen);
4054 s->f = ssh2_pkt_getmp(ssh);
4055 ssh2_pkt_getstring(ssh, &s->sigdata, &s->siglen);
e5574168 4056
27cd7fc2 4057 s->K = dh_find_K(ssh->kex_ctx, s->f);
e5574168 4058
51470298 4059 sha_string(&ssh->exhash, s->hostkeydata, s->hostkeylen);
4060 if (ssh->kex == &ssh_diffiehellman_gex) {
4061 sha_uint32(&ssh->exhash, s->pbits);
4062 sha_mpint(&ssh->exhash, s->p);
4063 sha_mpint(&ssh->exhash, s->g);
a92dd380 4064 }
51470298 4065 sha_mpint(&ssh->exhash, s->e);
4066 sha_mpint(&ssh->exhash, s->f);
4067 sha_mpint(&ssh->exhash, s->K);
4068 SHA_Final(&ssh->exhash, s->exchange_hash);
e5574168 4069
27cd7fc2 4070 dh_cleanup(ssh->kex_ctx);
fabd1805 4071 ssh->kex_ctx = NULL;
3709bfe9 4072
7cca0d81 4073#if 0
765c4200 4074 debug(("Exchange hash is:\n"));
51470298 4075 dmemdump(s->exchange_hash, 20);
7cca0d81 4076#endif
4077
51470298 4078 s->hkey = ssh->hostkey->newkey(s->hostkeydata, s->hostkeylen);
4079 if (!s->hkey ||
4080 !ssh->hostkey->verifysig(s->hkey, s->sigdata, s->siglen,
d8baa528 4081 (char *)s->exchange_hash, 20)) {
a8327734 4082 bombout((ssh,"Server's host key did not match the signature supplied"));
32874aea 4083 crReturn(0);
8d5de777 4084 }
e5574168 4085
4086 /*
7cca0d81 4087 * Authenticate remote host: verify host key. (We've already
4088 * checked the signature of the exchange hash.)
e5574168 4089 */
51470298 4090 s->keystr = ssh->hostkey->fmtkey(s->hkey);
4091 s->fingerprint = ssh->hostkey->fingerprint(s->hkey);
a8327734 4092 verify_ssh_host_key(ssh->frontend,
4093 ssh->savedhost, ssh->savedport, ssh->hostkey->keytype,
51470298 4094 s->keystr, s->fingerprint);
4095 if (s->first_kex) { /* don't bother logging this in rekeys */
5e0d7cb8 4096 logevent("Host key fingerprint is:");
51470298 4097 logevent(s->fingerprint);
5e0d7cb8 4098 }
51470298 4099 sfree(s->fingerprint);
4100 sfree(s->keystr);
4101 ssh->hostkey->freekey(s->hkey);
d39f364a 4102
4103 /*
7cca0d81 4104 * Send SSH2_MSG_NEWKEYS.
d39f364a 4105 */
51470298 4106 ssh2_pkt_init(ssh, SSH2_MSG_NEWKEYS);
4107 ssh2_pkt_send(ssh);
d39f364a 4108
4109 /*
8406eaf9 4110 * Expect SSH2_MSG_NEWKEYS from server.
4111 */
4112 crWaitUntil(ispkt);
51470298 4113 if (ssh->pktin.type != SSH2_MSG_NEWKEYS) {
a8327734 4114 bombout((ssh,"expected new-keys packet from server"));
8406eaf9 4115 crReturn(0);
4116 }
4117
4118 /*
d39f364a 4119 * Create and initialise session keys.
4120 */
371e569c 4121 if (ssh->cs_cipher_ctx)
4122 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
51470298 4123 ssh->cscipher = s->cscipher_tobe;
371e569c 4124 ssh->cs_cipher_ctx = ssh->cscipher->make_context();
e0e1a00d 4125
371e569c 4126 if (ssh->sc_cipher_ctx)
4127 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
51470298 4128 ssh->sccipher = s->sccipher_tobe;
371e569c 4129 ssh->sc_cipher_ctx = ssh->sccipher->make_context();
e0e1a00d 4130
4131 if (ssh->cs_mac_ctx)
4132 ssh->csmac->free_context(ssh->cs_mac_ctx);
51470298 4133 ssh->csmac = s->csmac_tobe;
e0e1a00d 4134 ssh->cs_mac_ctx = ssh->csmac->make_context();
4135
4136 if (ssh->sc_mac_ctx)
4137 ssh->scmac->free_context(ssh->sc_mac_ctx);
51470298 4138 ssh->scmac = s->scmac_tobe;
e0e1a00d 4139 ssh->sc_mac_ctx = ssh->scmac->make_context();
4140
5366aed8 4141 if (ssh->cs_comp_ctx)
4142 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
51470298 4143 ssh->cscomp = s->cscomp_tobe;
5366aed8 4144 ssh->cs_comp_ctx = ssh->cscomp->compress_init();
4145
4146 if (ssh->sc_comp_ctx)
4147 ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
51470298 4148 ssh->sccomp = s->sccomp_tobe;
5366aed8 4149 ssh->sc_comp_ctx = ssh->sccomp->decompress_init();
4150
d39f364a 4151 /*
5e0d7cb8 4152 * Set IVs after keys. Here we use the exchange hash from the
4153 * _first_ key exchange.
d39f364a 4154 */
51470298 4155 {
4156 unsigned char keyspace[40];
4157 if (s->first_kex)
4158 memcpy(ssh->v2_session_id, s->exchange_hash,
4159 sizeof(s->exchange_hash));
4160 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'C',keyspace);
371e569c 4161 ssh->cscipher->setkey(ssh->cs_cipher_ctx, keyspace);
51470298 4162 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'D',keyspace);
371e569c 4163 ssh->sccipher->setkey(ssh->sc_cipher_ctx, keyspace);
51470298 4164 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'A',keyspace);
371e569c 4165 ssh->cscipher->setiv(ssh->cs_cipher_ctx, keyspace);
51470298 4166 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'B',keyspace);
371e569c 4167 ssh->sccipher->setiv(ssh->sc_cipher_ctx, keyspace);
51470298 4168 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'E',keyspace);
e0e1a00d 4169 ssh->csmac->setkey(ssh->cs_mac_ctx, keyspace);
51470298 4170 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'F',keyspace);
e0e1a00d 4171 ssh->scmac->setkey(ssh->sc_mac_ctx, keyspace);
51470298 4172 }
57356d63 4173 logeventf(ssh, "Initialised %.200s client->server encryption",
4174 ssh->cscipher->text_name);
4175 logeventf(ssh, "Initialised %.200s server->client encryption",
4176 ssh->sccipher->text_name);
4177 if (ssh->cscomp->text_name)
4178 logeventf(ssh, "Initialised %s compression",
4179 ssh->cscomp->text_name);
4180 if (ssh->sccomp->text_name)
4181 logeventf(ssh, "Initialised %s decompression",
4182 ssh->sccomp->text_name);
d39f364a 4183
033b4cef 4184 /*
0db56f73 4185 * If this is the first key exchange phase, we must pass the
4186 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
4187 * wants to see it but because it will need time to initialise
4188 * itself before it sees an actual packet. In subsequent key
4189 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
4190 * it would only confuse the layer above.
4191 */
51470298 4192 if (!s->first_kex) {
32874aea 4193 crReturn(0);
0db56f73 4194 }
51470298 4195 s->first_kex = 0;
0db56f73 4196
4197 /*
7cca0d81 4198 * Now we're encrypting. Begin returning 1 to the protocol main
4199 * function so that other things can run on top of the
4200 * transport. If we ever see a KEXINIT, we must go back to the
4201 * start.
033b4cef 4202 */
51470298 4203 while (!(ispkt && ssh->pktin.type == SSH2_MSG_KEXINIT)) {
32874aea 4204 crReturn(1);
e96adf72 4205 }
5e0d7cb8 4206 logevent("Server initiated key re-exchange");
7cca0d81 4207 goto begin_key_exchange;
e5574168 4208
4209 crFinish(1);
4210}
4211
7cca0d81 4212/*
783415f8 4213 * Add data to an SSH2 channel output buffer.
4214 */
32874aea 4215static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
4216 int len)
4217{
5471d09a 4218 bufchain_add(&c->v.v2.outbuffer, buf, len);
783415f8 4219}
4220
4221/*
4222 * Attempt to send data on an SSH2 channel.
4223 */
5471d09a 4224static int ssh2_try_send(struct ssh_channel *c)
32874aea 4225{
51470298 4226 Ssh ssh = c->ssh;
4227
5471d09a 4228 while (c->v.v2.remwindow > 0 && bufchain_size(&c->v.v2.outbuffer) > 0) {
4229 int len;
4230 void *data;
4231 bufchain_prefix(&c->v.v2.outbuffer, &data, &len);
4232 if ((unsigned)len > c->v.v2.remwindow)
4233 len = c->v.v2.remwindow;
4234 if ((unsigned)len > c->v.v2.remmaxpkt)
4235 len = c->v.v2.remmaxpkt;
51470298 4236 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_DATA);
4237 ssh2_pkt_adduint32(ssh, c->remoteid);
4238 ssh2_pkt_addstring_start(ssh);
4239 ssh2_pkt_addstring_data(ssh, data, len);
4240 ssh2_pkt_send(ssh);
5471d09a 4241 bufchain_consume(&c->v.v2.outbuffer, len);
4242 c->v.v2.remwindow -= len;
4243 }
4244
4245 /*
4246 * After having sent as much data as we can, return the amount
4247 * still buffered.
4248 */
4249 return bufchain_size(&c->v.v2.outbuffer);
4250}
4251
4252/*
4253 * Potentially enlarge the window on an SSH2 channel.
4254 */
4255static void ssh2_set_window(struct ssh_channel *c, unsigned newwin)
4256{
51470298 4257 Ssh ssh = c->ssh;
4258
6b69f42e 4259 /*
4260 * Never send WINDOW_ADJUST for a channel that the remote side
4261 * already thinks it's closed; there's no point, since it won't
4262 * be sending any more data anyway.
4263 */
4264 if (c->closes != 0)
4265 return;
4266
5471d09a 4267 if (newwin > c->v.v2.locwindow) {
51470298 4268 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST);
4269 ssh2_pkt_adduint32(ssh, c->remoteid);
4270 ssh2_pkt_adduint32(ssh, newwin - c->v.v2.locwindow);
4271 ssh2_pkt_send(ssh);
5471d09a 4272 c->v.v2.locwindow = newwin;
783415f8 4273 }
4274}
4275
4276/*
7cca0d81 4277 * Handle the SSH2 userauth and connection layers.
4278 */
51470298 4279static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
7cca0d81 4280{
51470298 4281 struct do_ssh2_authconn_state {
4282 enum {
4283 AUTH_INVALID, AUTH_PUBLICKEY_AGENT, AUTH_PUBLICKEY_FILE,
4284 AUTH_PASSWORD,
4285 AUTH_KEYBOARD_INTERACTIVE
4286 } method;
4287 enum {
4288 AUTH_TYPE_NONE,
4289 AUTH_TYPE_PUBLICKEY,
4290 AUTH_TYPE_PUBLICKEY_OFFER_LOUD,
4291 AUTH_TYPE_PUBLICKEY_OFFER_QUIET,
4292 AUTH_TYPE_PASSWORD,
4293 AUTH_TYPE_KEYBOARD_INTERACTIVE,
4294 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
4295 } type;
4296 int gotit, need_pw, can_pubkey, can_passwd, can_keyb_inter;
4297 int tried_pubkey_config, tried_agent, tried_keyb_inter;
4298 int kbd_inter_running;
4299 int we_are_in;
4300 int num_prompts, curr_prompt, echo;
4301 char username[100];
4302 int got_username;
4303 char pwprompt[200];
4304 char password[100];
4305 void *publickey_blob;
4306 int publickey_bloblen;
4307 unsigned char request[5], *response, *p;
4308 int responselen;
4309 int keyi, nkeys;
4310 int authed;
4311 char *pkblob, *alg, *commentp;
4312 int pklen, alglen, commentlen;
4313 int siglen, retlen, len;
4314 char *q, *agentreq, *ret;
4315 int try_send;
4316 };
4317 crState(do_ssh2_authconn_state);
4318
4319 crBegin(ssh->do_ssh2_authconn_crstate);
e5574168 4320
7cca0d81 4321 /*
4322 * Request userauth protocol, and await a response to it.
4323 */
51470298 4324 ssh2_pkt_init(ssh, SSH2_MSG_SERVICE_REQUEST);
4325 ssh2_pkt_addstring(ssh, "ssh-userauth");
4326 ssh2_pkt_send(ssh);
7cca0d81 4327 crWaitUntilV(ispkt);
51470298 4328 if (ssh->pktin.type != SSH2_MSG_SERVICE_ACCEPT) {
a8327734 4329 bombout((ssh,"Server refused user authentication protocol"));
32874aea 4330 crReturnV;
8d5de777 4331 }
7cca0d81 4332
4333 /*
1408a877 4334 * We repeat this whole loop, including the username prompt,
4335 * until we manage a successful authentication. If the user
51470298 4336 * types the wrong _password_, they can be sent back to the
4337 * beginning to try another username, if this is configured on.
4338 * (If they specify a username in the config, they are never
4339 * asked, even if they do give a wrong password.)
1408a877 4340 *
4341 * I think this best serves the needs of
4342 *
4343 * - the people who have no configuration, no keys, and just
4344 * want to try repeated (username,password) pairs until they
4345 * type both correctly
4346 *
4347 * - people who have keys and configuration but occasionally
4348 * need to fall back to passwords
4349 *
4350 * - people with a key held in Pageant, who might not have
4351 * logged in to a particular machine before; so they want to
4352 * type a username, and then _either_ their key will be
4353 * accepted, _or_ they will type a password. If they mistype
4354 * the username they will want to be able to get back and
4355 * retype it!
7cca0d81 4356 */
51470298 4357 s->username[0] = '\0';
4358 s->got_username = FALSE;
1408a877 4359 do {
1408a877 4360 /*
4361 * Get a username.
4362 */
86916870 4363 if (s->got_username && !ssh->cfg.change_username) {
5bb641e1 4364 /*
4365 * We got a username last time round this loop, and
4366 * with change_username turned off we don't try to get
4367 * it again.
4368 */
86916870 4369 } else if ((flags & FLAG_INTERACTIVE) && !*ssh->cfg.username) {
c0a81592 4370 if (ssh_get_line && !ssh_getline_pw_only) {
32874aea 4371 if (!ssh_get_line("login as: ",
51470298 4372 s->username, sizeof(s->username), FALSE)) {
32874aea 4373 /*
4374 * get_line failed to get a username.
4375 * Terminate.
4376 */
4377 logevent("No username provided. Abandoning session.");
51470298 4378 ssh->state = SSH_STATE_CLOSED;
32874aea 4379 crReturnV;
4380 }
4381 } else {
51470298 4382 int ret; /* need not be saved across crReturn */
4383 c_write_str(ssh, "login as: ");
4384 ssh->send_ok = 1;
4385 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
0405e71f 4386 do {
32874aea 4387 crWaitUntilV(!ispkt);
51470298 4388 ret = process_userpass_input(ssh, in, inlen);
0405e71f 4389 } while (ret == 0);
4390 if (ret < 0)
4391 cleanup_exit(0);
4ca0c9d1 4392 c_write_str(ssh, "\r\n");
32874aea 4393 }
51470298 4394 s->username[strcspn(s->username, "\n\r")] = '\0';
7cca0d81 4395 } else {
57356d63 4396 char *stuff;
86916870 4397 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
51470298 4398 s->username[sizeof(s->username)-1] = '\0';
65a22376 4399 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
57356d63 4400 stuff = dupprintf("Using username \"%s\".\r\n", s->username);
51470298 4401 c_write_str(ssh, stuff);
57356d63 4402 sfree(stuff);
7cca0d81 4403 }
4404 }
51470298 4405 s->got_username = TRUE;
7cca0d81 4406
65a22376 4407 /*
1408a877 4408 * Send an authentication request using method "none": (a)
4409 * just in case it succeeds, and (b) so that we know what
4410 * authentication methods we can usefully try next.
65a22376 4411 */
51470298 4412 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4413
4414 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4415 ssh2_pkt_addstring(ssh, s->username);
4416 ssh2_pkt_addstring(ssh, "ssh-connection");/* service requested */
4417 ssh2_pkt_addstring(ssh, "none"); /* method */
4418 ssh2_pkt_send(ssh);
4419 s->type = AUTH_TYPE_NONE;
4420 s->gotit = FALSE;
4421 s->we_are_in = FALSE;
4422
4423 s->tried_pubkey_config = FALSE;
4424 s->tried_agent = FALSE;
4425 s->tried_keyb_inter = FALSE;
4426 s->kbd_inter_running = FALSE;
86916870 4427 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
9a30e26b 4428 if (!filename_is_null(ssh->cfg.keyfile)) {
231ee168 4429 int keytype;
6c6d9ed9 4430 logeventf(ssh, "Reading private key file \"%.150s\"",
4431 filename_to_str(&ssh->cfg.keyfile));
9a30e26b 4432 keytype = key_type(&ssh->cfg.keyfile);
51470298 4433 if (keytype == SSH_KEYTYPE_SSH2) {
4434 s->publickey_blob =
9a30e26b 4435 ssh2_userkey_loadpub(&ssh->cfg.keyfile, NULL,
51470298 4436 &s->publickey_bloblen);
4437 } else {
57356d63 4438 char *msgbuf;
c2ad7d0d 4439 logeventf(ssh, "Unable to use this key file (%s)",
a8327734 4440 key_type_to_str(keytype));
57356d63 4441 msgbuf = dupprintf("Unable to use key file \"%.150s\""
6c6d9ed9 4442 " (%s)\r\n",
4443 filename_to_str(&ssh->cfg.keyfile),
57356d63 4444 key_type_to_str(keytype));
51470298 4445 c_write_str(ssh, msgbuf);
57356d63 4446 sfree(msgbuf);
51470298 4447 s->publickey_blob = NULL;
231ee168 4448 }
396778f1 4449 } else
51470298 4450 s->publickey_blob = NULL;
65a22376 4451
1408a877 4452 while (1) {
4453 /*
4454 * Wait for the result of the last authentication request.
4455 */
51470298 4456 if (!s->gotit)
1408a877 4457 crWaitUntilV(ispkt);
51470298 4458 while (ssh->pktin.type == SSH2_MSG_USERAUTH_BANNER) {
32874aea 4459 char *banner;
4460 int size;
4461 /*
4462 * Don't show the banner if we're operating in
4463 * non-verbose non-interactive mode. (It's probably
4464 * a script, which means nobody will read the
4465 * banner _anyway_, and moreover the printing of
4466 * the banner will screw up processing on the
4467 * output of (say) plink.)
4468 */
4469 if (flags & (FLAG_VERBOSE | FLAG_INTERACTIVE)) {
51470298 4470 ssh2_pkt_getstring(ssh, &banner, &size);
32874aea 4471 if (banner)
51470298 4472 c_write_untrusted(ssh, banner, size);
32874aea 4473 }
1408a877 4474 crWaitUntilV(ispkt);
4475 }
51470298 4476 if (ssh->pktin.type == SSH2_MSG_USERAUTH_SUCCESS) {
1408a877 4477 logevent("Access granted");
51470298 4478 s->we_are_in = TRUE;
1408a877 4479 break;
4480 }
65a22376 4481
51470298 4482 if (s->kbd_inter_running &&
4483 ssh->pktin.type == SSH2_MSG_USERAUTH_INFO_REQUEST) {
b3186d64 4484 /*
45068b27 4485 * This is either a further set-of-prompts packet
4486 * in keyboard-interactive authentication, or it's
4487 * the same one and we came back here with `gotit'
4488 * set. In the former case, we must reset the
4489 * curr_prompt variable.
b3186d64 4490 */
51470298 4491 if (!s->gotit)
4492 s->curr_prompt = 0;
4493 } else if (ssh->pktin.type != SSH2_MSG_USERAUTH_FAILURE) {
a8327734 4494 bombout((ssh,"Strange packet received during authentication: type %d",
51470298 4495 ssh->pktin.type));
38c4a8da 4496 crReturnV;
65a22376 4497 }
4498
51470298 4499 s->gotit = FALSE;
65a22376 4500
1408a877 4501 /*
4502 * OK, we're now sitting on a USERAUTH_FAILURE message, so
4503 * we can look at the string in it and know what we can
4504 * helpfully try next.
4505 */
51470298 4506 if (ssh->pktin.type == SSH2_MSG_USERAUTH_FAILURE) {
1408a877 4507 char *methods;
4508 int methlen;
51470298 4509 ssh2_pkt_getstring(ssh, &methods, &methlen);
4510 s->kbd_inter_running = FALSE;
4511 if (!ssh2_pkt_getbool(ssh)) {
1408a877 4512 /*
4513 * We have received an unequivocal Access
4514 * Denied. This can translate to a variety of
4515 * messages:
4516 *
4517 * - if we'd just tried "none" authentication,
4518 * it's not worth printing anything at all
4519 *
4520 * - if we'd just tried a public key _offer_,
4521 * the message should be "Server refused our
4522 * key" (or no message at all if the key
4523 * came from Pageant)
4524 *
4525 * - if we'd just tried anything else, the
4526 * message really should be "Access denied".
4527 *
4528 * Additionally, if we'd just tried password
4529 * authentication, we should break out of this
4530 * whole loop so as to go back to the username
4531 * prompt.
4532 */
51470298 4533 if (s->type == AUTH_TYPE_NONE) {
1408a877 4534 /* do nothing */
51470298 4535 } else if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD ||
4536 s->type == AUTH_TYPE_PUBLICKEY_OFFER_QUIET) {
4537 if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD)
4538 c_write_str(ssh, "Server refused our key\r\n");
1408a877 4539 logevent("Server refused public key");
51470298 4540 } else if (s->type==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET) {
4bdf7c46 4541 /* server declined keyboard-interactive; ignore */
1408a877 4542 } else {
51470298 4543 c_write_str(ssh, "Access denied\r\n");
1408a877 4544 logevent("Access denied");
51470298 4545 if (s->type == AUTH_TYPE_PASSWORD) {
4546 s->we_are_in = FALSE;
1408a877 4547 break;
4548 }
4549 }
4550 } else {
51470298 4551 c_write_str(ssh, "Further authentication required\r\n");
1408a877 4552 logevent("Further authentication required");
4553 }
65a22376 4554
51470298 4555 s->can_pubkey =
32874aea 4556 in_commasep_string("publickey", methods, methlen);
51470298 4557 s->can_passwd =
32874aea 4558 in_commasep_string("password", methods, methlen);
86916870 4559 s->can_keyb_inter = ssh->cfg.try_ki_auth &&
761187b6 4560 in_commasep_string("keyboard-interactive", methods, methlen);
1408a877 4561 }
65a22376 4562
51470298 4563 s->method = 0;
4564 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
65a22376 4565
0405e71f 4566 /*
4567 * Most password/passphrase prompts will be
4568 * non-echoing, so we set this to 0 by default.
4569 * Exception is that some keyboard-interactive prompts
4570 * can be echoing, in which case we'll set this to 1.
4571 */
51470298 4572 s->echo = 0;
0405e71f 4573
51470298 4574 if (!s->method && s->can_pubkey &&
4575 agent_exists() && !s->tried_agent) {
1983e559 4576 /*
4577 * Attempt public-key authentication using Pageant.
4578 */
1983e559 4579 void *r;
51470298 4580 s->authed = FALSE;
1983e559 4581
51470298 4582 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4583 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
00db133f 4584
51470298 4585 s->tried_agent = TRUE;
1983e559 4586
4587 logevent("Pageant is running. Requesting keys.");
4588
4589 /* Request the keys held by the agent. */
51470298 4590 PUT_32BIT(s->request, 1);
4591 s->request[4] = SSH2_AGENTC_REQUEST_IDENTITIES;
4592 agent_query(s->request, 5, &r, &s->responselen);
4593 s->response = (unsigned char *) r;
4594 if (s->response && s->responselen >= 5 &&
4595 s->response[4] == SSH2_AGENT_IDENTITIES_ANSWER) {
4596 s->p = s->response + 5;
4597 s->nkeys = GET_32BIT(s->p);
4598 s->p += 4;
32874aea 4599 {
4600 char buf[64];
51470298 4601 sprintf(buf, "Pageant has %d SSH2 keys", s->nkeys);
32874aea 4602 logevent(buf);
4603 }
51470298 4604 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
2d466ffd 4605 void *vret;
1983e559 4606
32874aea 4607 {
4608 char buf[64];
51470298 4609 sprintf(buf, "Trying Pageant key #%d", s->keyi);
32874aea 4610 logevent(buf);
4611 }
51470298 4612 s->pklen = GET_32BIT(s->p);
4613 s->p += 4;
4614 if (s->publickey_blob &&
4615 s->pklen == s->publickey_bloblen &&
4616 !memcmp(s->p, s->publickey_blob,
4617 s->publickey_bloblen)) {
396778f1 4618 logevent("This key matches configured key file");
51470298 4619 s->tried_pubkey_config = 1;
396778f1 4620 }
d8baa528 4621 s->pkblob = (char *)s->p;
51470298 4622 s->p += s->pklen;
4623 s->alglen = GET_32BIT(s->pkblob);
4624 s->alg = s->pkblob + 4;
4625 s->commentlen = GET_32BIT(s->p);
4626 s->p += 4;
d8baa528 4627 s->commentp = (char *)s->p;
51470298 4628 s->p += s->commentlen;
4629 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4630 ssh2_pkt_addstring(ssh, s->username);
4631 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
4632 ssh2_pkt_addstring(ssh, "publickey"); /* method */
4633 ssh2_pkt_addbool(ssh, FALSE); /* no signature included */
4634 ssh2_pkt_addstring_start(ssh);
4635 ssh2_pkt_addstring_data(ssh, s->alg, s->alglen);
4636 ssh2_pkt_addstring_start(ssh);
4637 ssh2_pkt_addstring_data(ssh, s->pkblob, s->pklen);
4638 ssh2_pkt_send(ssh);
1983e559 4639
4640 crWaitUntilV(ispkt);
51470298 4641 if (ssh->pktin.type != SSH2_MSG_USERAUTH_PK_OK) {
1983e559 4642 logevent("Key refused");
4643 continue;
4644 }
4645
32874aea 4646 if (flags & FLAG_VERBOSE) {
51470298 4647 c_write_str(ssh, "Authenticating with "
4648 "public key \"");
4649 c_write(ssh, s->commentp, s->commentlen);
4650 c_write_str(ssh, "\" from agent\r\n");
32874aea 4651 }
1983e559 4652
4653 /*
4654 * Server is willing to accept the key.
4655 * Construct a SIGN_REQUEST.
4656 */
51470298 4657 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4658 ssh2_pkt_addstring(ssh, s->username);
4659 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
4660 ssh2_pkt_addstring(ssh, "publickey"); /* method */
4661 ssh2_pkt_addbool(ssh, TRUE);
4662 ssh2_pkt_addstring_start(ssh);
4663 ssh2_pkt_addstring_data(ssh, s->alg, s->alglen);
4664 ssh2_pkt_addstring_start(ssh);
4665 ssh2_pkt_addstring_data(ssh, s->pkblob, s->pklen);
4666
4667 s->siglen = ssh->pktout.length - 5 + 4 + 20;
dda87a28 4668 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
4669 s->siglen -= 4;
51470298 4670 s->len = 1; /* message type */
4671 s->len += 4 + s->pklen; /* key blob */
4672 s->len += 4 + s->siglen; /* data to sign */
4673 s->len += 4; /* flags */
4674 s->agentreq = smalloc(4 + s->len);
4675 PUT_32BIT(s->agentreq, s->len);
4676 s->q = s->agentreq + 4;
4677 *s->q++ = SSH2_AGENTC_SIGN_REQUEST;
4678 PUT_32BIT(s->q, s->pklen);
4679 s->q += 4;
4680 memcpy(s->q, s->pkblob, s->pklen);
4681 s->q += s->pklen;
4682 PUT_32BIT(s->q, s->siglen);
4683 s->q += 4;
1983e559 4684 /* Now the data to be signed... */
dda87a28 4685 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
4686 PUT_32BIT(s->q, 20);
4687 s->q += 4;
4688 }
51470298 4689 memcpy(s->q, ssh->v2_session_id, 20);
4690 s->q += 20;
4691 memcpy(s->q, ssh->pktout.data + 5,
4692 ssh->pktout.length - 5);
4693 s->q += ssh->pktout.length - 5;
1983e559 4694 /* And finally the (zero) flags word. */
51470298 4695 PUT_32BIT(s->q, 0);
4696 agent_query(s->agentreq, s->len + 4, &vret, &s->retlen);
4697 s->ret = vret;
4698 sfree(s->agentreq);
4699 if (s->ret) {
4700 if (s->ret[4] == SSH2_AGENT_SIGN_RESPONSE) {
1983e559 4701 logevent("Sending Pageant's response");
51470298 4702 ssh2_add_sigblob(ssh, s->pkblob, s->pklen,
4703 s->ret + 9,
4704 GET_32BIT(s->ret + 5));
4705 ssh2_pkt_send(ssh);
4706 s->authed = TRUE;
1983e559 4707 break;
4708 } else {
32874aea 4709 logevent
4710 ("Pageant failed to answer challenge");
51470298 4711 sfree(s->ret);
1983e559 4712 }
4713 }
4714 }
51470298 4715 if (s->authed)
1983e559 4716 continue;
4717 }
4718 }
4719
51470298 4720 if (!s->method && s->can_pubkey && s->publickey_blob
4721 && !s->tried_pubkey_config) {
1408a877 4722 unsigned char *pub_blob;
4723 char *algorithm, *comment;
4724 int pub_blob_len;
65a22376 4725
51470298 4726 s->tried_pubkey_config = TRUE;
65a22376 4727
51470298 4728 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4729 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
00db133f 4730
65a22376 4731 /*
1408a877 4732 * Try the public key supplied in the configuration.
4733 *
4734 * First, offer the public blob to see if the server is
4735 * willing to accept it.
65a22376 4736 */
d8baa528 4737 pub_blob =
9a30e26b 4738 (unsigned char *)ssh2_userkey_loadpub(&ssh->cfg.keyfile,
d8baa528 4739 &algorithm,
4740 &pub_blob_len);
1408a877 4741 if (pub_blob) {
51470298 4742 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4743 ssh2_pkt_addstring(ssh, s->username);
4744 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
4745 ssh2_pkt_addstring(ssh, "publickey"); /* method */
4746 ssh2_pkt_addbool(ssh, FALSE); /* no signature included */
4747 ssh2_pkt_addstring(ssh, algorithm);
4748 ssh2_pkt_addstring_start(ssh);
d8baa528 4749 ssh2_pkt_addstring_data(ssh, (char *)pub_blob,
4750 pub_blob_len);
51470298 4751 ssh2_pkt_send(ssh);
32874aea 4752 logevent("Offered public key"); /* FIXME */
1408a877 4753
4754 crWaitUntilV(ispkt);
51470298 4755 if (ssh->pktin.type != SSH2_MSG_USERAUTH_PK_OK) {
4756 s->gotit = TRUE;
4757 s->type = AUTH_TYPE_PUBLICKEY_OFFER_LOUD;
32874aea 4758 continue; /* key refused; give up on it */
1408a877 4759 }
65a22376 4760
1408a877 4761 logevent("Offer of public key accepted");
65a22376 4762 /*
1408a877 4763 * Actually attempt a serious authentication using
4764 * the key.
65a22376 4765 */
9a30e26b 4766 if (ssh2_userkey_encrypted(&ssh->cfg.keyfile, &comment)) {
51470298 4767 sprintf(s->pwprompt,
32874aea 4768 "Passphrase for key \"%.100s\": ",
4769 comment);
51470298 4770 s->need_pw = TRUE;
1408a877 4771 } else {
51470298 4772 s->need_pw = FALSE;
1408a877 4773 }
51470298 4774 c_write_str(ssh, "Authenticating with public key \"");
4775 c_write_str(ssh, comment);
4776 c_write_str(ssh, "\"\r\n");
4777 s->method = AUTH_PUBLICKEY_FILE;
65a22376 4778 }
1408a877 4779 }
4780
51470298 4781 if (!s->method && s->can_keyb_inter && !s->tried_keyb_inter) {
4782 s->method = AUTH_KEYBOARD_INTERACTIVE;
4783 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
4784 s->tried_keyb_inter = TRUE;
af659722 4785
51470298 4786 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4787 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
00db133f 4788
51470298 4789 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4790 ssh2_pkt_addstring(ssh, s->username);
4791 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
4792 ssh2_pkt_addstring(ssh, "keyboard-interactive"); /* method */
4793 ssh2_pkt_addstring(ssh, ""); /* lang */
4794 ssh2_pkt_addstring(ssh, "");
4795 ssh2_pkt_send(ssh);
af659722 4796
4797 crWaitUntilV(ispkt);
51470298 4798 if (ssh->pktin.type != SSH2_MSG_USERAUTH_INFO_REQUEST) {
4799 if (ssh->pktin.type == SSH2_MSG_USERAUTH_FAILURE)
4800 s->gotit = TRUE;
af659722 4801 logevent("Keyboard-interactive authentication refused");
51470298 4802 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET;
af659722 4803 continue;
4804 }
4805
51470298 4806 s->kbd_inter_running = TRUE;
4807 s->curr_prompt = 0;
af659722 4808 }
4809
51470298 4810 if (s->kbd_inter_running) {
4811 s->method = AUTH_KEYBOARD_INTERACTIVE;
4812 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
4813 s->tried_keyb_inter = TRUE;
af659722 4814
51470298 4815 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4816 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
00db133f 4817
51470298 4818 if (s->curr_prompt == 0) {
45068b27 4819 /*
4820 * We've got a fresh USERAUTH_INFO_REQUEST.
4821 * Display header data, and start going through
4822 * the prompts.
4823 */
4824 char *name, *inst, *lang;
4825 int name_len, inst_len, lang_len;
4826
51470298 4827 ssh2_pkt_getstring(ssh, &name, &name_len);
4828 ssh2_pkt_getstring(ssh, &inst, &inst_len);
4829 ssh2_pkt_getstring(ssh, &lang, &lang_len);
45068b27 4830 if (name_len > 0) {
51470298 4831 c_write_untrusted(ssh, name, name_len);
4832 c_write_str(ssh, "\r\n");
45068b27 4833 }
4834 if (inst_len > 0) {
51470298 4835 c_write_untrusted(ssh, inst, inst_len);
4836 c_write_str(ssh, "\r\n");
45068b27 4837 }
51470298 4838 s->num_prompts = ssh2_pkt_getuint32(ssh);
45068b27 4839 }
af659722 4840
45068b27 4841 /*
4842 * If there are prompts remaining in the packet,
4843 * display one and get a response.
4844 */
51470298 4845 if (s->curr_prompt < s->num_prompts) {
45068b27 4846 char *prompt;
4847 int prompt_len;
af659722 4848
51470298 4849 ssh2_pkt_getstring(ssh, &prompt, &prompt_len);
45068b27 4850 if (prompt_len > 0) {
51470298 4851 strncpy(s->pwprompt, prompt, sizeof(s->pwprompt));
4852 s->pwprompt[prompt_len < sizeof(s->pwprompt) ?
4853 prompt_len : sizeof(s->pwprompt)-1] = '\0';
45068b27 4854 } else {
51470298 4855 strcpy(s->pwprompt,
45068b27 4856 "<server failed to send prompt>: ");
4857 }
51470298 4858 s->echo = ssh2_pkt_getbool(ssh);
4859 s->need_pw = TRUE;
45068b27 4860 } else
51470298 4861 s->need_pw = FALSE;
af659722 4862 }
4863
51470298 4864 if (!s->method && s->can_passwd) {
4865 s->method = AUTH_PASSWORD;
4866 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4867 ssh->pkt_ctx |= SSH2_PKTCTX_PASSWORD;
4868 sprintf(s->pwprompt, "%.90s@%.90s's password: ", s->username,
4869 ssh->savedhost);
4870 s->need_pw = TRUE;
1408a877 4871 }
4872
51470298 4873 if (s->need_pw) {
fa17a66e 4874 if (ssh_get_line) {
51470298 4875 if (!ssh_get_line(s->pwprompt, s->password,
4876 sizeof(s->password), TRUE)) {
1408a877 4877 /*
fa17a66e 4878 * get_line failed to get a password (for
4879 * example because one was supplied on the
4880 * command line which has already failed to
4881 * work). Terminate.
1408a877 4882 */
51470298 4883 ssh2_pkt_init(ssh, SSH2_MSG_DISCONNECT);
4884 ssh2_pkt_adduint32(ssh,SSH2_DISCONNECT_BY_APPLICATION);
4885 ssh2_pkt_addstring(ssh, "No more passwords available"
4886 " to try");
4887 ssh2_pkt_addstring(ssh, "en"); /* language tag */
4888 ssh2_pkt_send(ssh);
247308b5 4889 logevent("Unable to authenticate");
a8327734 4890 connection_fatal(ssh->frontend,
4891 "Unable to authenticate");
51470298 4892 ssh->state = SSH_STATE_CLOSED;
1408a877 4893 crReturnV;
4894 }
4895 } else {
51470298 4896 int ret; /* need not be saved across crReturn */
4897 c_write_untrusted(ssh, s->pwprompt, strlen(s->pwprompt));
4898 ssh->send_ok = 1;
1408a877 4899
51470298 4900 setup_userpass_input(ssh, s->password,
4901 sizeof(s->password), s->echo);
0405e71f 4902 do {
1408a877 4903 crWaitUntilV(!ispkt);
51470298 4904 ret = process_userpass_input(ssh, in, inlen);
0405e71f 4905 } while (ret == 0);
4906 if (ret < 0)
4907 cleanup_exit(0);
51470298 4908 c_write_str(ssh, "\r\n");
65a22376 4909 }
65a22376 4910 }
65a22376 4911
51470298 4912 if (s->method == AUTH_PUBLICKEY_FILE) {
1408a877 4913 /*
4914 * We have our passphrase. Now try the actual authentication.
4915 */
4916 struct ssh2_userkey *key;
65a22376 4917
9a30e26b 4918 key = ssh2_load_userkey(&ssh->cfg.keyfile, s->password);
1408a877 4919 if (key == SSH2_WRONG_PASSPHRASE || key == NULL) {
4920 if (key == SSH2_WRONG_PASSPHRASE) {
51470298 4921 c_write_str(ssh, "Wrong passphrase\r\n");
4922 s->tried_pubkey_config = FALSE;
1408a877 4923 } else {
51470298 4924 c_write_str(ssh, "Unable to load private key\r\n");
4925 s->tried_pubkey_config = TRUE;
1408a877 4926 }
4927 /* Send a spurious AUTH_NONE to return to the top. */
51470298 4928 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4929 ssh2_pkt_addstring(ssh, s->username);
4930 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
4931 ssh2_pkt_addstring(ssh, "none"); /* method */
4932 ssh2_pkt_send(ssh);
4933 s->type = AUTH_TYPE_NONE;
1408a877 4934 } else {
1dd353b5 4935 unsigned char *pkblob, *sigblob, *sigdata;
4936 int pkblob_len, sigblob_len, sigdata_len;
dda87a28 4937 int p;
65a22376 4938
1408a877 4939 /*
4940 * We have loaded the private key and the server
4941 * has announced that it's willing to accept it.
4942 * Hallelujah. Generate a signature and send it.
4943 */
51470298 4944 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4945 ssh2_pkt_addstring(ssh, s->username);
4946 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
4947 ssh2_pkt_addstring(ssh, "publickey"); /* method */
4948 ssh2_pkt_addbool(ssh, TRUE);
4949 ssh2_pkt_addstring(ssh, key->alg->name);
1dd353b5 4950 pkblob = key->alg->public_blob(key->data, &pkblob_len);
51470298 4951 ssh2_pkt_addstring_start(ssh);
d8baa528 4952 ssh2_pkt_addstring_data(ssh, (char *)pkblob, pkblob_len);
1408a877 4953
4954 /*
4955 * The data to be signed is:
4956 *
4957 * string session-id
4958 *
4959 * followed by everything so far placed in the
4960 * outgoing packet.
4961 */
51470298 4962 sigdata_len = ssh->pktout.length - 5 + 4 + 20;
dda87a28 4963 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
4964 sigdata_len -= 4;
1408a877 4965 sigdata = smalloc(sigdata_len);
dda87a28 4966 p = 0;
4967 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
4968 PUT_32BIT(sigdata+p, 20);
4969 p += 4;
4970 }
4971 memcpy(sigdata+p, ssh->v2_session_id, 20); p += 20;
4972 memcpy(sigdata+p, ssh->pktout.data + 5,
51470298 4973 ssh->pktout.length - 5);
dda87a28 4974 p += ssh->pktout.length - 5;
4975 assert(p == sigdata_len);
d8baa528 4976 sigblob = key->alg->sign(key->data, (char *)sigdata,
1dd353b5 4977 sigdata_len, &sigblob_len);
51470298 4978 ssh2_add_sigblob(ssh, pkblob, pkblob_len,
1dd353b5 4979 sigblob, sigblob_len);
4980 sfree(pkblob);
4981 sfree(sigblob);
1408a877 4982 sfree(sigdata);
4983
51470298 4984 ssh2_pkt_send(ssh);
4985 s->type = AUTH_TYPE_PUBLICKEY;
1408a877 4986 }
51470298 4987 } else if (s->method == AUTH_PASSWORD) {
65a22376 4988 /*
1408a877 4989 * We send the password packet lumped tightly together with
4990 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
4991 * string long enough to make the total length of the two
4992 * packets constant. This should ensure that a passive
4993 * listener doing traffic analyis can't work out the length
4994 * of the password.
4995 *
4996 * For this to work, we need an assumption about the
4997 * maximum length of the password packet. I think 256 is
4998 * pretty conservative. Anyone using a password longer than
4999 * that probably doesn't have much to worry about from
5000 * people who find out how long their password is!
65a22376 5001 */
51470298 5002 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
5003 ssh2_pkt_addstring(ssh, s->username);
5004 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
5005 ssh2_pkt_addstring(ssh, "password");
5006 ssh2_pkt_addbool(ssh, FALSE);
5007 ssh2_pkt_addstring(ssh, s->password);
1409c1b3 5008 memset(s->password, 0, sizeof(s->password));
51470298 5009 ssh2_pkt_defer(ssh);
65a22376 5010 /*
1408a877 5011 * We'll include a string that's an exact multiple of the
5012 * cipher block size. If the cipher is NULL for some
5013 * reason, we don't do this trick at all because we gain
5014 * nothing by it.
65a22376 5015 */
51470298 5016 if (ssh->cscipher) {
32874aea 5017 int stringlen, i;
5018
51470298 5019 stringlen = (256 - ssh->deferred_len);
5020 stringlen += ssh->cscipher->blksize - 1;
5021 stringlen -= (stringlen % ssh->cscipher->blksize);
5022 if (ssh->cscomp) {
32874aea 5023 /*
5024 * Temporarily disable actual compression,
5025 * so we can guarantee to get this string
5026 * exactly the length we want it. The
5027 * compression-disabling routine should
5028 * return an integer indicating how many
5029 * bytes we should adjust our string length
5030 * by.
5031 */
5366aed8 5032 stringlen -=
5033 ssh->cscomp->disable_compression(ssh->cs_comp_ctx);
32874aea 5034 }
51470298 5035 ssh2_pkt_init(ssh, SSH2_MSG_IGNORE);
5036 ssh2_pkt_addstring_start(ssh);
6e9e9520 5037 for (i = 0; i < stringlen; i++) {
32874aea 5038 char c = (char) random_byte();
51470298 5039 ssh2_pkt_addstring_data(ssh, &c, 1);
65a22376 5040 }
51470298 5041 ssh2_pkt_defer(ssh);
65a22376 5042 }
51470298 5043 ssh_pkt_defersend(ssh);
0d43337a 5044 logevent("Sent password");
51470298 5045 s->type = AUTH_TYPE_PASSWORD;
5046 } else if (s->method == AUTH_KEYBOARD_INTERACTIVE) {
5047 if (s->curr_prompt == 0) {
5048 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_INFO_RESPONSE);
5049 ssh2_pkt_adduint32(ssh, s->num_prompts);
45068b27 5050 }
51470298 5051 if (s->need_pw) { /* only add pw if we just got one! */
5052 ssh2_pkt_addstring(ssh, s->password);
5053 memset(s->password, 0, sizeof(s->password));
5054 s->curr_prompt++;
45068b27 5055 }
51470298 5056 if (s->curr_prompt >= s->num_prompts) {
5057 ssh2_pkt_send(ssh);
45068b27 5058 } else {
5059 /*
5060 * If there are prompts remaining, we set
5061 * `gotit' so that we won't attempt to get
5062 * another packet. Then we go back round the
5063 * loop and will end up retrieving another
5064 * prompt out of the existing packet. Funky or
5065 * what?
5066 */
51470298 5067 s->gotit = TRUE;
45068b27 5068 }
51470298 5069 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
1408a877 5070 } else {
51470298 5071 c_write_str(ssh, "No supported authentication methods"
5072 " left to try!\r\n");
5073 logevent("No supported authentications offered."
5074 " Disconnecting");
5075 ssh2_pkt_init(ssh, SSH2_MSG_DISCONNECT);
5076 ssh2_pkt_adduint32(ssh, SSH2_DISCONNECT_BY_APPLICATION);
5077 ssh2_pkt_addstring(ssh, "No supported authentication"
5078 " methods available");
5079 ssh2_pkt_addstring(ssh, "en"); /* language tag */
5080 ssh2_pkt_send(ssh);
5081 ssh->state = SSH_STATE_CLOSED;
1408a877 5082 crReturnV;
65a22376 5083 }
65a22376 5084 }
51470298 5085 } while (!s->we_are_in);
7cca0d81 5086
5087 /*
5088 * Now we're authenticated for the connection protocol. The
5089 * connection protocol will automatically have started at this
5090 * point; there's no need to send SERVICE_REQUEST.
5091 */
5092
5093 /*
5094 * So now create a channel with a session in it.
5095 */
51470298 5096 ssh->channels = newtree234(ssh_channelcmp);
5097 ssh->mainchan = smalloc(sizeof(struct ssh_channel));
5098 ssh->mainchan->ssh = ssh;
5099 ssh->mainchan->localid = alloc_channel_id(ssh);
5100 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_OPEN);
5101 ssh2_pkt_addstring(ssh, "session");
5102 ssh2_pkt_adduint32(ssh, ssh->mainchan->localid);
5103 ssh->mainchan->v.v2.locwindow = OUR_V2_WINSIZE;
5104 ssh2_pkt_adduint32(ssh, ssh->mainchan->v.v2.locwindow);/* our window size */
5105 ssh2_pkt_adduint32(ssh, 0x4000UL); /* our max pkt size */
5106 ssh2_pkt_send(ssh);
7cca0d81 5107 crWaitUntilV(ispkt);
51470298 5108 if (ssh->pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
a8327734 5109 bombout((ssh,"Server refused to open a session"));
32874aea 5110 crReturnV;
5111 /* FIXME: error data comes back in FAILURE packet */
7cca0d81 5112 }
51470298 5113 if (ssh2_pkt_getuint32(ssh) != ssh->mainchan->localid) {
a8327734 5114 bombout((ssh,"Server's channel confirmation cited wrong channel"));
32874aea 5115 crReturnV;
7cca0d81 5116 }
51470298 5117 ssh->mainchan->remoteid = ssh2_pkt_getuint32(ssh);
5118 ssh->mainchan->type = CHAN_MAINSESSION;
5119 ssh->mainchan->closes = 0;
5120 ssh->mainchan->v.v2.remwindow = ssh2_pkt_getuint32(ssh);
5121 ssh->mainchan->v.v2.remmaxpkt = ssh2_pkt_getuint32(ssh);
5122 bufchain_init(&ssh->mainchan->v.v2.outbuffer);
5123 add234(ssh->channels, ssh->mainchan);
7cca0d81 5124 logevent("Opened channel for session");
5125
5126 /*
783415f8 5127 * Potentially enable X11 forwarding.
5128 */
86916870 5129 if (ssh->cfg.x11_forward) {
32874aea 5130 char proto[20], data[64];
5131 logevent("Requesting X11 forwarding");
302121de 5132 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
86916870 5133 data, sizeof(data), ssh->cfg.x11_auth);
5134 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
51470298 5135 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
5136 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
5137 ssh2_pkt_addstring(ssh, "x11-req");
5138 ssh2_pkt_addbool(ssh, 1); /* want reply */
5139 ssh2_pkt_addbool(ssh, 0); /* many connections */
5140 ssh2_pkt_addstring(ssh, proto);
5141 ssh2_pkt_addstring(ssh, data);
86916870 5142 ssh2_pkt_adduint32(ssh, x11_get_screen_number(ssh->cfg.x11_display));
51470298 5143 ssh2_pkt_send(ssh);
32874aea 5144
5145 do {
5146 crWaitUntilV(ispkt);
51470298 5147 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
5148 unsigned i = ssh2_pkt_getuint32(ssh);
32874aea 5149 struct ssh_channel *c;
51470298 5150 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5151 if (!c)
5152 continue; /* nonexistent channel */
51470298 5153 c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
32874aea 5154 }
51470298 5155 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
32874aea 5156
51470298 5157 if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
5158 if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
a8327734 5159 bombout((ssh,"Unexpected response to X11 forwarding request:"
51470298 5160 " packet type %d", ssh->pktin.type));
32874aea 5161 crReturnV;
5162 }
5163 logevent("X11 forwarding refused");
5164 } else {
5165 logevent("X11 forwarding enabled");
51470298 5166 ssh->X11_fwd_enabled = TRUE;
32874aea 5167 }
783415f8 5168 }
5169
5170 /*
bc240b21 5171 * Enable port forwardings.
5172 */
5173 {
bc240b21 5174 char type;
5175 int n;
a4fc0d74 5176 int sport,dport,sserv,dserv;
6ee9b735 5177 char sports[256], dports[256], saddr[256], host[256];
bc240b21 5178
51470298 5179 ssh->rportfwds = newtree234(ssh_rportcmp_ssh2);
bc240b21 5180 /* Add port forwardings. */
86916870 5181 ssh->portfwd_strptr = ssh->cfg.portfwd;
51470298 5182 while (*ssh->portfwd_strptr) {
5183 type = *ssh->portfwd_strptr++;
6ee9b735 5184 saddr[0] = '\0';
bc240b21 5185 n = 0;
6ee9b735 5186 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != '\t') {
5187 if (*ssh->portfwd_strptr == ':') {
5188 /*
5189 * We've seen a colon in the middle of the
5190 * source port number. This means that
5191 * everything we've seen until now is the
5192 * source _address_, so we'll move it into
5193 * saddr and start sports from the beginning
5194 * again.
5195 */
5196 ssh->portfwd_strptr++;
5197 sports[n] = '\0';
5198 strcpy(saddr, sports);
5199 n = 0;
5200 }
5201 if (n < 255) sports[n++] = *ssh->portfwd_strptr++;
5202 }
bc240b21 5203 sports[n] = 0;
51470298 5204 if (*ssh->portfwd_strptr == '\t')
5205 ssh->portfwd_strptr++;
bc240b21 5206 n = 0;
6ee9b735 5207 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != ':') {
5208 if (n < 255) host[n++] = *ssh->portfwd_strptr++;
5209 }
bc240b21 5210 host[n] = 0;
51470298 5211 if (*ssh->portfwd_strptr == ':')
5212 ssh->portfwd_strptr++;
bc240b21 5213 n = 0;
6ee9b735 5214 while (*ssh->portfwd_strptr) {
5215 if (n < 255) dports[n++] = *ssh->portfwd_strptr++;
5216 }
bc240b21 5217 dports[n] = 0;
51470298 5218 ssh->portfwd_strptr++;
bc240b21 5219 dport = atoi(dports);
a4fc0d74 5220 dserv = 0;
5221 if (dport == 0) {
5222 dserv = 1;
68a49acb 5223 dport = net_service_lookup(dports);
5224 if (!dport) {
57356d63 5225 logeventf(ssh, "Service lookup failed for destination"
5226 " port \"%s\"", dports);
a4fc0d74 5227 }
5228 }
bc240b21 5229 sport = atoi(sports);
a4fc0d74 5230 sserv = 0;
5231 if (sport == 0) {
5232 sserv = 1;
68a49acb 5233 sport = net_service_lookup(sports);
5234 if (!sport) {
57356d63 5235 logeventf(ssh, "Service lookup failed for source"
5236 " port \"%s\"", sports);
a4fc0d74 5237 }
5238 }
bc240b21 5239 if (sport && dport) {
5240 if (type == 'L') {
6ee9b735 5241 pfd_addforward(host, dport, *saddr ? saddr : NULL,
e8fa8f62 5242 sport, ssh, &ssh->cfg);
6ee9b735 5243 logeventf(ssh, "Local port %.*s%.*s%.*s%.*s%d%.*s"
5244 " forwarding to %s:%.*s%.*s%d%.*s",
5245 (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
5246 (int)(*saddr?1:0), ":",
57356d63 5247 (int)(sserv ? strlen(sports) : 0), sports,
5248 sserv, "(", sport, sserv, ")",
5249 host,
5250 (int)(dserv ? strlen(dports) : 0), dports,
5251 dserv, "(", dport, dserv, ")");
bc240b21 5252 } else {
5253 struct ssh_rportfwd *pf;
5254 pf = smalloc(sizeof(*pf));
5255 strcpy(pf->dhost, host);
5256 pf->dport = dport;
5257 pf->sport = sport;
51470298 5258 if (add234(ssh->rportfwds, pf) != pf) {
57356d63 5259 logeventf(ssh, "Duplicate remote port forwarding"
5260 " to %s:%d", host, dport);
bc240b21 5261 sfree(pf);
5262 } else {
6ee9b735 5263 logeventf(ssh, "Requesting remote port "
5264 "%.*s%.*s%.*s%.*s%d%.*s"
57356d63 5265 " forward to %s:%.*s%.*s%d%.*s",
6ee9b735 5266 (int)(*saddr?strlen(saddr):0),
5267 *saddr?saddr:NULL,
5268 (int)(*saddr?1:0), ":",
57356d63 5269 (int)(sserv ? strlen(sports) : 0), sports,
5270 sserv, "(", sport, sserv, ")",
5271 host,
5272 (int)(dserv ? strlen(dports) : 0), dports,
5273 dserv, "(", dport, dserv, ")");
51470298 5274 ssh2_pkt_init(ssh, SSH2_MSG_GLOBAL_REQUEST);
5275 ssh2_pkt_addstring(ssh, "tcpip-forward");
5276 ssh2_pkt_addbool(ssh, 1);/* want reply */
6ee9b735 5277 if (*saddr)
5278 ssh2_pkt_addstring(ssh, saddr);
86916870 5279 if (ssh->cfg.rport_acceptall)
51470298 5280 ssh2_pkt_addstring(ssh, "0.0.0.0");
beefa433 5281 else
51470298 5282 ssh2_pkt_addstring(ssh, "127.0.0.1");
5283 ssh2_pkt_adduint32(ssh, sport);
5284 ssh2_pkt_send(ssh);
bc240b21 5285
5286 do {
5287 crWaitUntilV(ispkt);
51470298 5288 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
5289 unsigned i = ssh2_pkt_getuint32(ssh);
bc240b21 5290 struct ssh_channel *c;
51470298 5291 c = find234(ssh->channels, &i, ssh_channelfind);
bc240b21 5292 if (!c)
5293 continue;/* nonexistent channel */
51470298 5294 c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
bc240b21 5295 }
51470298 5296 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
bc240b21 5297
51470298 5298 if (ssh->pktin.type != SSH2_MSG_REQUEST_SUCCESS) {
5299 if (ssh->pktin.type != SSH2_MSG_REQUEST_FAILURE) {
a8327734 5300 bombout((ssh,"Unexpected response to port "
c9886e66 5301 "forwarding request: packet type %d",
51470298 5302 ssh->pktin.type));
bc240b21 5303 crReturnV;
5304 }
5305 logevent("Server refused this port forwarding");
5306 } else {
5307 logevent("Remote port forwarding enabled");
5308 }
5309 }
5310 }
5311 }
5312 }
5313 }
5314
5315 /*
36c2a3e9 5316 * Potentially enable agent forwarding.
5317 */
86916870 5318 if (ssh->cfg.agentfwd && agent_exists()) {
32874aea 5319 logevent("Requesting OpenSSH-style agent forwarding");
51470298 5320 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
5321 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
5322 ssh2_pkt_addstring(ssh, "auth-agent-req@openssh.com");
5323 ssh2_pkt_addbool(ssh, 1); /* want reply */
5324 ssh2_pkt_send(ssh);
32874aea 5325
5326 do {
5327 crWaitUntilV(ispkt);
51470298 5328 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
5329 unsigned i = ssh2_pkt_getuint32(ssh);
32874aea 5330 struct ssh_channel *c;
51470298 5331 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5332 if (!c)
5333 continue; /* nonexistent channel */
51470298 5334 c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
32874aea 5335 }
51470298 5336 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
32874aea 5337
51470298 5338 if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
5339 if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
a8327734 5340 bombout((ssh,"Unexpected response to agent forwarding request:"
51470298 5341 " packet type %d", ssh->pktin.type));
32874aea 5342 crReturnV;
5343 }
5344 logevent("Agent forwarding refused");
5345 } else {
5346 logevent("Agent forwarding enabled");
51470298 5347 ssh->agentfwd_enabled = TRUE;
32874aea 5348 }
36c2a3e9 5349 }
5350
5351 /*
7cca0d81 5352 * Now allocate a pty for the session.
5353 */
86916870 5354 if (!ssh->cfg.nopty) {
51470298 5355 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
5356 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid); /* recipient channel */
5357 ssh2_pkt_addstring(ssh, "pty-req");
5358 ssh2_pkt_addbool(ssh, 1); /* want reply */
86916870 5359 ssh2_pkt_addstring(ssh, ssh->cfg.termtype);
51470298 5360 ssh2_pkt_adduint32(ssh, ssh->term_width);
5361 ssh2_pkt_adduint32(ssh, ssh->term_height);
5362 ssh2_pkt_adduint32(ssh, 0); /* pixel width */
5363 ssh2_pkt_adduint32(ssh, 0); /* pixel height */
5364 ssh2_pkt_addstring_start(ssh);
5365 ssh2_pkt_addstring_data(ssh, "\0", 1); /* TTY_OP_END, no special options */
5366 ssh2_pkt_send(ssh);
5367 ssh->state = SSH_STATE_INTERMED;
32874aea 5368
5369 do {
5370 crWaitUntilV(ispkt);
51470298 5371 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
5372 unsigned i = ssh2_pkt_getuint32(ssh);
32874aea 5373 struct ssh_channel *c;
51470298 5374 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5375 if (!c)
5376 continue; /* nonexistent channel */
51470298 5377 c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
32874aea 5378 }
51470298 5379 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
32874aea 5380
51470298 5381 if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
5382 if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
a8327734 5383 bombout((ssh,"Unexpected response to pty request:"
51470298 5384 " packet type %d", ssh->pktin.type));
32874aea 5385 crReturnV;
5386 }
51470298 5387 c_write_str(ssh, "Server refused to allocate pty\r\n");
5388 ssh->editing = ssh->echoing = 1;
32874aea 5389 } else {
5390 logevent("Allocated pty");
5391 }
0965bee0 5392 } else {
51470298 5393 ssh->editing = ssh->echoing = 1;
7cca0d81 5394 }
5395
5396 /*
fd5e5847 5397 * Start a shell or a remote command. We may have to attempt
5398 * this twice if the config data has provided a second choice
5399 * of command.
7cca0d81 5400 */
fd5e5847 5401 while (1) {
5402 int subsys;
5403 char *cmd;
5404
51470298 5405 if (ssh->fallback_cmd) {
86916870 5406 subsys = ssh->cfg.ssh_subsys2;
5407 cmd = ssh->cfg.remote_cmd_ptr2;
fd5e5847 5408 } else {
86916870 5409 subsys = ssh->cfg.ssh_subsys;
5410 cmd = ssh->cfg.remote_cmd_ptr;
fd5e5847 5411 }
5412
51470298 5413 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
5414 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid); /* recipient channel */
fd5e5847 5415 if (subsys) {
51470298 5416 ssh2_pkt_addstring(ssh, "subsystem");
5417 ssh2_pkt_addbool(ssh, 1); /* want reply */
5418 ssh2_pkt_addstring(ssh, cmd);
fd5e5847 5419 } else if (*cmd) {
51470298 5420 ssh2_pkt_addstring(ssh, "exec");
5421 ssh2_pkt_addbool(ssh, 1); /* want reply */
5422 ssh2_pkt_addstring(ssh, cmd);
fd5e5847 5423 } else {
51470298 5424 ssh2_pkt_addstring(ssh, "shell");
5425 ssh2_pkt_addbool(ssh, 1); /* want reply */
32874aea 5426 }
51470298 5427 ssh2_pkt_send(ssh);
fd5e5847 5428 do {
5429 crWaitUntilV(ispkt);
51470298 5430 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
5431 unsigned i = ssh2_pkt_getuint32(ssh);
fd5e5847 5432 struct ssh_channel *c;
51470298 5433 c = find234(ssh->channels, &i, ssh_channelfind);
fd5e5847 5434 if (!c)
5435 continue; /* nonexistent channel */
51470298 5436 c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
fd5e5847 5437 }
51470298 5438 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
5439 if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
5440 if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
a8327734 5441 bombout((ssh,"Unexpected response to shell/command request:"
51470298 5442 " packet type %d", ssh->pktin.type));
fd5e5847 5443 crReturnV;
5444 }
5445 /*
5446 * We failed to start the command. If this is the
5447 * fallback command, we really are finished; if it's
5448 * not, and if the fallback command exists, try falling
5449 * back to it before complaining.
5450 */
86916870 5451 if (!ssh->fallback_cmd && ssh->cfg.remote_cmd_ptr2 != NULL) {
fd5e5847 5452 logevent("Primary command failed; attempting fallback");
51470298 5453 ssh->fallback_cmd = TRUE;
fd5e5847 5454 continue;
5455 }
a8327734 5456 bombout((ssh,"Server refused to start a shell/command"));
32874aea 5457 crReturnV;
fd5e5847 5458 } else {
5459 logevent("Started a shell/command");
32874aea 5460 }
fd5e5847 5461 break;
7cca0d81 5462 }
5463
51470298 5464 ssh->state = SSH_STATE_SESSION;
5465 if (ssh->size_needed)
5466 ssh_size(ssh, ssh->term_width, ssh->term_height);
5467 if (ssh->eof_needed)
5468 ssh_special(ssh, TS_EOF);
6e48c3fe 5469
7cca0d81 5470 /*
5471 * Transfer data!
5472 */
b9d7bcad 5473 if (ssh->ldisc)
5474 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
51470298 5475 ssh->send_ok = 1;
7cca0d81 5476 while (1) {
e5574168 5477 crReturnV;
51470298 5478 s->try_send = FALSE;
7cca0d81 5479 if (ispkt) {
51470298 5480 if (ssh->pktin.type == SSH2_MSG_CHANNEL_DATA ||
5481 ssh->pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
32874aea 5482 char *data;
5483 int length;
51470298 5484 unsigned i = ssh2_pkt_getuint32(ssh);
32874aea 5485 struct ssh_channel *c;
51470298 5486 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5487 if (!c)
5488 continue; /* nonexistent channel */
51470298 5489 if (ssh->pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
5490 ssh2_pkt_getuint32(ssh) != SSH2_EXTENDED_DATA_STDERR)
32874aea 5491 continue; /* extended but not stderr */
51470298 5492 ssh2_pkt_getstring(ssh, &data, &length);
32874aea 5493 if (data) {
5471d09a 5494 int bufsize;
5495 c->v.v2.locwindow -= length;
32874aea 5496 switch (c->type) {
5497 case CHAN_MAINSESSION:
5471d09a 5498 bufsize =
51470298 5499 from_backend(ssh->frontend, ssh->pktin.type ==
5471d09a 5500 SSH2_MSG_CHANNEL_EXTENDED_DATA,
5501 data, length);
32874aea 5502 break;
5503 case CHAN_X11:
5471d09a 5504 bufsize = x11_send(c->u.x11.s, data, length);
32874aea 5505 break;
d74d141c 5506 case CHAN_SOCKDATA:
5471d09a 5507 bufsize = pfd_send(c->u.pfd.s, data, length);
bc240b21 5508 break;
36c2a3e9 5509 case CHAN_AGENT:
32874aea 5510 while (length > 0) {
5511 if (c->u.a.lensofar < 4) {
5512 int l = min(4 - c->u.a.lensofar, length);
5513 memcpy(c->u.a.msglen + c->u.a.lensofar,
5514 data, l);
5515 data += l;
5516 length -= l;
5517 c->u.a.lensofar += l;
5518 }
5519 if (c->u.a.lensofar == 4) {
5520 c->u.a.totallen =
5521 4 + GET_32BIT(c->u.a.msglen);
5522 c->u.a.message = smalloc(c->u.a.totallen);
5523 memcpy(c->u.a.message, c->u.a.msglen, 4);
5524 }
5525 if (c->u.a.lensofar >= 4 && length > 0) {
5526 int l =
5527 min(c->u.a.totallen - c->u.a.lensofar,
5528 length);
5529 memcpy(c->u.a.message + c->u.a.lensofar,
5530 data, l);
5531 data += l;
5532 length -= l;
5533 c->u.a.lensofar += l;
5534 }
5535 if (c->u.a.lensofar == c->u.a.totallen) {
5536 void *reply, *sentreply;
5537 int replylen;
5538 agent_query(c->u.a.message,
5539 c->u.a.totallen, &reply,
5540 &replylen);
5541 if (reply)
5542 sentreply = reply;
5543 else {
5544 /* Fake SSH_AGENT_FAILURE. */
5545 sentreply = "\0\0\0\1\5";
5546 replylen = 5;
5547 }
51470298 5548 ssh2_add_channel_data(c, sentreply, replylen);
5549 s->try_send = TRUE;
32874aea 5550 if (reply)
5551 sfree(reply);
5552 sfree(c->u.a.message);
5553 c->u.a.lensofar = 0;
5554 }
5555 }
5471d09a 5556 bufsize = 0;
32874aea 5557 break;
5558 }
5559 /*
5471d09a 5560 * If we are not buffering too much data,
5561 * enlarge the window again at the remote side.
32874aea 5562 */
5471d09a 5563 if (bufsize < OUR_V2_WINSIZE)
5564 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
32874aea 5565 }
51470298 5566 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_EOF) {
5567 unsigned i = ssh2_pkt_getuint32(ssh);
32874aea 5568 struct ssh_channel *c;
5569
51470298 5570 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5571 if (!c)
5572 continue; /* nonexistent channel */
5573
5574 if (c->type == CHAN_X11) {
5575 /*
5576 * Remote EOF on an X11 channel means we should
5577 * wrap up and close the channel ourselves.
5578 */
5579 x11_close(c->u.x11.s);
5580 sshfwd_close(c);
5581 } else if (c->type == CHAN_AGENT) {
36c2a3e9 5582 sshfwd_close(c);
d74d141c 5583 } else if (c->type == CHAN_SOCKDATA) {
bc240b21 5584 pfd_close(c->u.pfd.s);
5585 sshfwd_close(c);
36c2a3e9 5586 }
51470298 5587 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_CLOSE) {
5588 unsigned i = ssh2_pkt_getuint32(ssh);
32874aea 5589 struct ssh_channel *c;
5590
51470298 5591 c = find234(ssh->channels, &i, ssh_channelfind);
d0d844c1 5592 if (!c || ((int)c->remoteid) == -1) {
a8327734 5593 bombout((ssh,"Received CHANNEL_CLOSE for %s channel %d\n",
d0d844c1 5594 c ? "half-open" : "nonexistent", i));
5595 }
32874aea 5596 /* Do pre-close processing on the channel. */
5597 switch (c->type) {
5598 case CHAN_MAINSESSION:
5599 break; /* nothing to see here, move along */
5600 case CHAN_X11:
92f157bd 5601 if (c->u.x11.s != NULL)
5602 x11_close(c->u.x11.s);
5603 sshfwd_close(c);
32874aea 5604 break;
5605 case CHAN_AGENT:
92f157bd 5606 sshfwd_close(c);
32874aea 5607 break;
d74d141c 5608 case CHAN_SOCKDATA:
92f157bd 5609 if (c->u.pfd.s != NULL)
5610 pfd_close(c->u.pfd.s);
5611 sshfwd_close(c);
bc240b21 5612 break;
32874aea 5613 }
92f157bd 5614 if (c->closes == 0) {
51470298 5615 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_CLOSE);
5616 ssh2_pkt_adduint32(ssh, c->remoteid);
5617 ssh2_pkt_send(ssh);
92f157bd 5618 }
51470298 5619 del234(ssh->channels, c);
5471d09a 5620 bufchain_clear(&c->v.v2.outbuffer);
32874aea 5621 sfree(c);
5622
5623 /*
5624 * See if that was the last channel left open.
5625 */
51470298 5626 if (count234(ssh->channels) == 0) {
ca2914d1 5627#if 0
5628 /*
5629 * We used to send SSH_MSG_DISCONNECT here,
5630 * because I'd believed that _every_ conforming
5631 * SSH2 connection had to end with a disconnect
5632 * being sent by at least one side; apparently
5633 * I was wrong and it's perfectly OK to
5634 * unceremoniously slam the connection shut
5635 * when you're done, and indeed OpenSSH feels
5636 * this is more polite than sending a
5637 * DISCONNECT. So now we don't.
5638 */
32874aea 5639 logevent("All channels closed. Disconnecting");
51470298 5640 ssh2_pkt_init(ssh, SSH2_MSG_DISCONNECT);
5641 ssh2_pkt_adduint32(ssh, SSH2_DISCONNECT_BY_APPLICATION);
5642 ssh2_pkt_addstring(ssh, "All open channels closed");
5643 ssh2_pkt_addstring(ssh, "en"); /* language tag */
5644 ssh2_pkt_send(ssh);
ca2914d1 5645#endif
51470298 5646 ssh->state = SSH_STATE_CLOSED;
32874aea 5647 crReturnV;
5648 }
5649 continue; /* remote sends close; ignore (FIXME) */
51470298 5650 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
5651 unsigned i = ssh2_pkt_getuint32(ssh);
32874aea 5652 struct ssh_channel *c;
51470298 5653 c = find234(ssh->channels, &i, ssh_channelfind);
a6253970 5654 if (!c || c->closes)
5655 continue; /* nonexistent or closing channel */
51470298 5656 c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
5657 s->try_send = TRUE;
5658 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
5659 unsigned i = ssh2_pkt_getuint32(ssh);
bc240b21 5660 struct ssh_channel *c;
51470298 5661 c = find234(ssh->channels, &i, ssh_channelfind);
bc240b21 5662 if (!c)
5663 continue; /* nonexistent channel */
5664 if (c->type != CHAN_SOCKDATA_DORMANT)
5665 continue; /* dunno why they're confirming this */
51470298 5666 c->remoteid = ssh2_pkt_getuint32(ssh);
bc240b21 5667 c->type = CHAN_SOCKDATA;
51470298 5668 c->v.v2.remwindow = ssh2_pkt_getuint32(ssh);
5669 c->v.v2.remmaxpkt = ssh2_pkt_getuint32(ssh);
4ed34d25 5670 if (c->u.pfd.s)
5671 pfd_confirm(c->u.pfd.s);
5672 if (c->closes) {
5673 /*
5674 * We have a pending close on this channel,
5675 * which we decided on before the server acked
5676 * the channel open. So now we know the
5677 * remoteid, we can close it again.
5678 */
51470298 5679 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_CLOSE);
5680 ssh2_pkt_adduint32(ssh, c->remoteid);
5681 ssh2_pkt_send(ssh);
4ed34d25 5682 }
51470298 5683 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_OPEN_FAILURE) {
5684 unsigned i = ssh2_pkt_getuint32(ssh);
724cface 5685 struct ssh_channel *c;
51470298 5686 c = find234(ssh->channels, &i, ssh_channelfind);
724cface 5687 if (!c)
5688 continue; /* nonexistent channel */
5689 if (c->type != CHAN_SOCKDATA_DORMANT)
5690 continue; /* dunno why they're failing this */
5691
5692 logevent("Forwarded connection refused by server");
5693
5694 pfd_close(c->u.pfd.s);
5695
51470298 5696 del234(ssh->channels, c);
724cface 5697 sfree(c);
51470298 5698 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_REQUEST) {
ebb0a590 5699 unsigned localid;
5700 char *type;
5701 int typelen, want_reply;
5702 struct ssh_channel *c;
5703
51470298 5704 localid = ssh2_pkt_getuint32(ssh);
5705 ssh2_pkt_getstring(ssh, &type, &typelen);
5706 want_reply = ssh2_pkt_getbool(ssh);
ebb0a590 5707
5708 /*
5709 * First, check that the channel exists. Otherwise,
5710 * we can instantly disconnect with a rude message.
5711 */
51470298 5712 c = find234(ssh->channels, &localid, ssh_channelfind);
ebb0a590 5713 if (!c) {
5714 char buf[80];
5715 sprintf(buf, "Received channel request for nonexistent"
5716 " channel %d", localid);
5717 logevent(buf);
51470298 5718 ssh2_pkt_init(ssh, SSH2_MSG_DISCONNECT);
5719 ssh2_pkt_adduint32(ssh, SSH2_DISCONNECT_BY_APPLICATION);
5720 ssh2_pkt_addstring(ssh, buf);
5721 ssh2_pkt_addstring(ssh, "en"); /* language tag */
5722 ssh2_pkt_send(ssh);
247308b5 5723 connection_fatal("%s", buf);
51470298 5724 ssh->state = SSH_STATE_CLOSED;
ebb0a590 5725 crReturnV;
5726 }
5727
5728 /*
d8d6c7e5 5729 * Having got the channel number, we now look at
5730 * the request type string to see if it's something
5731 * we recognise.
ebb0a590 5732 */
d8d6c7e5 5733 if (typelen == 11 && !memcmp(type, "exit-status", 11) &&
51470298 5734 c == ssh->mainchan) {
d8d6c7e5 5735 /* We recognise "exit-status" on the primary channel. */
5736 char buf[100];
51470298 5737 ssh->exitcode = ssh2_pkt_getuint32(ssh);
d8d6c7e5 5738 sprintf(buf, "Server sent command exit status %d",
51470298 5739 ssh->exitcode);
d8d6c7e5 5740 logevent(buf);
5741 if (want_reply) {
51470298 5742 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_SUCCESS);
5743 ssh2_pkt_adduint32(ssh, c->remoteid);
5744 ssh2_pkt_send(ssh);
d8d6c7e5 5745 }
5746 } else {
5747 /*
5748 * This is a channel request we don't know
5749 * about, so we now either ignore the request
5750 * or respond with CHANNEL_FAILURE, depending
5751 * on want_reply.
5752 */
5753 if (want_reply) {
51470298 5754 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_FAILURE);
5755 ssh2_pkt_adduint32(ssh, c->remoteid);
5756 ssh2_pkt_send(ssh);
d8d6c7e5 5757 }
ebb0a590 5758 }
51470298 5759 } else if (ssh->pktin.type == SSH2_MSG_GLOBAL_REQUEST) {
697d4856 5760 char *type;
5761 int typelen, want_reply;
5762
51470298 5763 ssh2_pkt_getstring(ssh, &type, &typelen);
5764 want_reply = ssh2_pkt_getbool(ssh);
697d4856 5765
5766 /*
5767 * We currently don't support any global requests
5768 * at all, so we either ignore the request or
5769 * respond with REQUEST_FAILURE, depending on
5770 * want_reply.
5771 */
5772 if (want_reply) {
51470298 5773 ssh2_pkt_init(ssh, SSH2_MSG_REQUEST_FAILURE);
5774 ssh2_pkt_send(ssh);
697d4856 5775 }
51470298 5776 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_OPEN) {
32874aea 5777 char *type;
5778 int typelen;
b3ebaa28 5779 char *peeraddr;
5780 int peeraddrlen;
5781 int port;
32874aea 5782 char *error = NULL;
5783 struct ssh_channel *c;
bc240b21 5784 unsigned remid, winsize, pktsize;
51470298 5785 ssh2_pkt_getstring(ssh, &type, &typelen);
32874aea 5786 c = smalloc(sizeof(struct ssh_channel));
51470298 5787 c->ssh = ssh;
32874aea 5788
51470298 5789 remid = ssh2_pkt_getuint32(ssh);
5790 winsize = ssh2_pkt_getuint32(ssh);
5791 pktsize = ssh2_pkt_getuint32(ssh);
b3ebaa28 5792 ssh2_pkt_getstring(ssh, &peeraddr, &peeraddrlen);
5793 port = ssh2_pkt_getuint32(ssh);
bc240b21 5794
32874aea 5795 if (typelen == 3 && !memcmp(type, "x11", 3)) {
b3ebaa28 5796 char *addrstr = smalloc(peeraddrlen+1);
5797 memcpy(addrstr, peeraddr, peeraddrlen);
5798 peeraddr[peeraddrlen] = '\0';
5799
51470298 5800 if (!ssh->X11_fwd_enabled)
32874aea 5801 error = "X11 forwarding is not enabled";
86916870 5802 else if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
e8fa8f62 5803 ssh->x11auth, addrstr, port,
5804 &ssh->cfg) != NULL) {
32874aea 5805 error = "Unable to open an X11 connection";
5806 } else {
5807 c->type = CHAN_X11;
5808 }
b3ebaa28 5809
5810 sfree(addrstr);
bc240b21 5811 } else if (typelen == 15 &&
5812 !memcmp(type, "forwarded-tcpip", 15)) {
5813 struct ssh_rportfwd pf, *realpf;
5814 char *dummy;
5815 int dummylen;
51470298 5816 ssh2_pkt_getstring(ssh, &dummy, &dummylen);/* skip address */
5817 pf.sport = ssh2_pkt_getuint32(ssh);
5818 realpf = find234(ssh->rportfwds, &pf, NULL);
bc240b21 5819 if (realpf == NULL) {
5820 error = "Remote port is not recognised";
5821 } else {
5822 char *e = pfd_newconnect(&c->u.pfd.s, realpf->dhost,
e8fa8f62 5823 realpf->dport, c, &ssh->cfg);
57356d63 5824 logeventf(ssh, "Received remote port open request"
5825 " for %s:%d", realpf->dhost, realpf->dport);
bc240b21 5826 if (e != NULL) {
57356d63 5827 logeventf(ssh, "Port open failed: %s", e);
bc240b21 5828 error = "Port open failed";
5829 } else {
5830 logevent("Forwarded port opened successfully");
5831 c->type = CHAN_SOCKDATA;
5832 }
5833 }
32874aea 5834 } else if (typelen == 22 &&
36c2a3e9 5835 !memcmp(type, "auth-agent@openssh.com", 3)) {
51470298 5836 if (!ssh->agentfwd_enabled)
32874aea 5837 error = "Agent forwarding is not enabled";
36c2a3e9 5838 else {
32874aea 5839 c->type = CHAN_AGENT; /* identify channel type */
36c2a3e9 5840 c->u.a.lensofar = 0;
32874aea 5841 }
5842 } else {
5843 error = "Unsupported channel type requested";
5844 }
5845
bc240b21 5846 c->remoteid = remid;
32874aea 5847 if (error) {
51470298 5848 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_OPEN_FAILURE);
5849 ssh2_pkt_adduint32(ssh, c->remoteid);
5850 ssh2_pkt_adduint32(ssh, SSH2_OPEN_CONNECT_FAILED);
5851 ssh2_pkt_addstring(ssh, error);
5852 ssh2_pkt_addstring(ssh, "en"); /* language tag */
5853 ssh2_pkt_send(ssh);
32874aea 5854 sfree(c);
5855 } else {
51470298 5856 c->localid = alloc_channel_id(ssh);
32874aea 5857 c->closes = 0;
5471d09a 5858 c->v.v2.locwindow = OUR_V2_WINSIZE;
5859 c->v.v2.remwindow = winsize;
5860 c->v.v2.remmaxpkt = pktsize;
5861 bufchain_init(&c->v.v2.outbuffer);
51470298 5862 add234(ssh->channels, c);
5863 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
5864 ssh2_pkt_adduint32(ssh, c->remoteid);
5865 ssh2_pkt_adduint32(ssh, c->localid);
5866 ssh2_pkt_adduint32(ssh, c->v.v2.locwindow);
5867 ssh2_pkt_adduint32(ssh, 0x4000UL); /* our max pkt size */
5868 ssh2_pkt_send(ssh);
32874aea 5869 }
7cca0d81 5870 } else {
a8327734 5871 bombout((ssh,"Strange packet received: type %d", ssh->pktin.type));
32874aea 5872 crReturnV;
7cca0d81 5873 }
5874 } else {
32874aea 5875 /*
5876 * We have spare data. Add it to the channel buffer.
5877 */
d8baa528 5878 ssh2_add_channel_data(ssh->mainchan, (char *)in, inlen);
51470298 5879 s->try_send = TRUE;
32874aea 5880 }
51470298 5881 if (s->try_send) {
32874aea 5882 int i;
5883 struct ssh_channel *c;
5884 /*
5885 * Try to send data on all channels if we can.
5886 */
51470298 5887 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
a6253970 5888 int bufsize;
5889 if (c->closes)
5890 continue; /* don't send on closing channels */
5891 bufsize = ssh2_try_send(c);
5471d09a 5892 if (bufsize == 0) {
5893 switch (c->type) {
5894 case CHAN_MAINSESSION:
5895 /* stdin need not receive an unthrottle
5896 * notification since it will be polled */
5897 break;
5898 case CHAN_X11:
5899 x11_unthrottle(c->u.x11.s);
5900 break;
5901 case CHAN_AGENT:
5902 /* agent sockets are request/response and need no
5903 * buffer management */
5904 break;
5905 case CHAN_SOCKDATA:
5906 pfd_unthrottle(c->u.pfd.s);
5907 break;
5908 }
5909 }
5910 }
7cca0d81 5911 }
e5574168 5912 }
5913
5914 crFinishV;
5915}
5916
5917/*
7cca0d81 5918 * Handle the top-level SSH2 protocol.
5919 */
51470298 5920static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
7cca0d81 5921{
51470298 5922 if (do_ssh2_transport(ssh, in, inlen, ispkt) == 0)
32874aea 5923 return;
51470298 5924 do_ssh2_authconn(ssh, in, inlen, ispkt);
7cca0d81 5925}
5926
5927/*
8df7a775 5928 * Called to set up the connection.
374330e2 5929 *
5930 * Returns an error message, or NULL on success.
374330e2 5931 */
51470298 5932static char *ssh_init(void *frontend_handle, void **backend_handle,
86916870 5933 Config *cfg,
887035a5 5934 char *host, int port, char **realhost, int nodelay)
32874aea 5935{
fb09bf1c 5936 char *p;
51470298 5937 Ssh ssh;
5938
5939 ssh = smalloc(sizeof(*ssh));
86916870 5940 ssh->cfg = *cfg; /* STRUCTURE COPY */
51470298 5941 ssh->s = NULL;
5942 ssh->cipher = NULL;
371e569c 5943 ssh->v1_cipher_ctx = NULL;
0183b242 5944 ssh->crcda_ctx = NULL;
51470298 5945 ssh->cscipher = NULL;
371e569c 5946 ssh->cs_cipher_ctx = NULL;
51470298 5947 ssh->sccipher = NULL;
371e569c 5948 ssh->sc_cipher_ctx = NULL;
51470298 5949 ssh->csmac = NULL;
a8327734 5950 ssh->cs_mac_ctx = NULL;
51470298 5951 ssh->scmac = NULL;
e0e1a00d 5952 ssh->sc_mac_ctx = NULL;
51470298 5953 ssh->cscomp = NULL;
5366aed8 5954 ssh->cs_comp_ctx = NULL;
51470298 5955 ssh->sccomp = NULL;
5366aed8 5956 ssh->sc_comp_ctx = NULL;
51470298 5957 ssh->kex = NULL;
389aa499 5958 ssh->kex_ctx = NULL;
51470298 5959 ssh->hostkey = NULL;
5960 ssh->exitcode = -1;
5961 ssh->state = SSH_STATE_PREPACKET;
5962 ssh->size_needed = FALSE;
5963 ssh->eof_needed = FALSE;
b9d7bcad 5964 ssh->ldisc = NULL;
a8327734 5965 ssh->logctx = NULL;
51470298 5966 {
5967 static const struct Packet empty = { 0, 0, NULL, NULL, 0 };
5968 ssh->pktin = ssh->pktout = empty;
5969 }
5970 ssh->deferred_send_data = NULL;
5971 ssh->deferred_len = 0;
5972 ssh->deferred_size = 0;
5973 ssh->fallback_cmd = 0;
5974 ssh->pkt_ctx = 0;
302121de 5975 ssh->x11auth = NULL;
be738459 5976 ssh->v1_compressing = FALSE;
51470298 5977 ssh->v2_outgoing_sequence = 0;
5978 ssh->ssh1_rdpkt_crstate = 0;
5979 ssh->ssh2_rdpkt_crstate = 0;
5980 ssh->do_ssh_init_crstate = 0;
5981 ssh->ssh_gotdata_crstate = 0;
5982 ssh->ssh1_protocol_crstate = 0;
5983 ssh->do_ssh1_login_crstate = 0;
5984 ssh->do_ssh2_transport_crstate = 0;
5985 ssh->do_ssh2_authconn_crstate = 0;
5986 ssh->do_ssh_init_state = NULL;
5987 ssh->do_ssh1_login_state = NULL;
5988 ssh->do_ssh2_transport_state = NULL;
5989 ssh->do_ssh2_authconn_state = NULL;
6571dbfd 5990 ssh->mainchan = NULL;
968d2d92 5991 ssh->throttled_all = 0;
5992 ssh->v1_stdout_throttling = 0;
51470298 5993
5994 *backend_handle = ssh;
32874aea 5995
8f203108 5996#ifdef MSCRYPTOAPI
32874aea 5997 if (crypto_startup() == 0)
8f203108 5998 return "Microsoft high encryption pack not installed!";
5999#endif
374330e2 6000
51470298 6001 ssh->frontend = frontend_handle;
86916870 6002 ssh->term_width = ssh->cfg.width;
6003 ssh->term_height = ssh->cfg.height;
887035a5 6004
fabd1805 6005 ssh->channels = NULL;
6006 ssh->rportfwds = NULL;
6007
51470298 6008 ssh->send_ok = 0;
6009 ssh->editing = 0;
6010 ssh->echoing = 0;
6011 ssh->v1_throttle_count = 0;
6012 ssh->overall_bufsize = 0;
6013 ssh->fallback_cmd = 0;
8df7a775 6014
3648d4c5 6015 ssh->protocol = NULL;
6016
51470298 6017 p = connect_to_host(ssh, host, port, realhost, nodelay);
fb09bf1c 6018 if (p != NULL)
6019 return p;
374330e2 6020
374330e2 6021 return NULL;
6022}
6023
fabd1805 6024static void ssh_free(void *handle)
6025{
6026 Ssh ssh = (Ssh) handle;
6027 struct ssh_channel *c;
6028 struct ssh_rportfwd *pf;
6029
6030 if (ssh->v1_cipher_ctx)
6031 ssh->cipher->free_context(ssh->v1_cipher_ctx);
6032 if (ssh->cs_cipher_ctx)
6033 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
6034 if (ssh->sc_cipher_ctx)
6035 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
6036 if (ssh->cs_mac_ctx)
6037 ssh->csmac->free_context(ssh->cs_mac_ctx);
6038 if (ssh->sc_mac_ctx)
6039 ssh->scmac->free_context(ssh->sc_mac_ctx);
6040 if (ssh->cs_comp_ctx)
6041 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
6042 if (ssh->sc_comp_ctx)
6043 ssh->sccomp->compress_cleanup(ssh->sc_comp_ctx);
6044 if (ssh->kex_ctx)
6045 dh_cleanup(ssh->kex_ctx);
6046 sfree(ssh->savedhost);
6047
6048 if (ssh->channels) {
6049 while ((c = delpos234(ssh->channels, 0)) != NULL) {
6050 switch (c->type) {
6051 case CHAN_X11:
6052 if (c->u.x11.s != NULL)
6053 x11_close(c->u.x11.s);
6054 break;
6055 case CHAN_SOCKDATA:
6056 if (c->u.pfd.s != NULL)
6057 pfd_close(c->u.pfd.s);
6058 break;
6059 }
6060 sfree(c);
6061 }
6062 freetree234(ssh->channels);
6063 }
6064
6065 if (ssh->rportfwds) {
6066 while ((pf = delpos234(ssh->rportfwds, 0)) != NULL)
6067 sfree(pf);
6068 freetree234(ssh->rportfwds);
6069 }
6070 sfree(ssh->deferred_send_data);
6071 if (ssh->x11auth)
6072 x11_free_auth(ssh->x11auth);
6073 sfree(ssh->do_ssh_init_state);
6074 sfree(ssh->do_ssh1_login_state);
6075 sfree(ssh->do_ssh2_transport_state);
6076 sfree(ssh->do_ssh2_authconn_state);
6077
6078 if (ssh->s)
6079 sk_close(ssh->s);
6080 sfree(ssh);
6081}
6082
374330e2 6083/*
86916870 6084 * Reconfigure the SSH backend.
6085 *
6086 * Currently, this function does nothing very useful. In future,
6087 * however, we could do some handy things with it. For example, we
6088 * could make the port forwarding configurer active in the Change
6089 * Settings box, and this routine could close down existing
6090 * forwardings and open up new ones in response to changes.
6091 */
6092static void ssh_reconfig(void *handle, Config *cfg)
6093{
6094 Ssh ssh = (Ssh) handle;
6095 ssh->cfg = *cfg; /* STRUCTURE COPY */
6096}
6097
6098/*
374330e2 6099 * Called to send data down the Telnet connection.
6100 */
51470298 6101static int ssh_send(void *handle, char *buf, int len)
32874aea 6102{
51470298 6103 Ssh ssh = (Ssh) handle;
6104
6105 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
5471d09a 6106 return 0;
374330e2 6107
d8baa528 6108 ssh->protocol(ssh, (unsigned char *)buf, len, 0);
5471d09a 6109
51470298 6110 return ssh_sendbuffer(ssh);
5471d09a 6111}
6112
6113/*
6114 * Called to query the current amount of buffered stdin data.
6115 */
51470298 6116static int ssh_sendbuffer(void *handle)
5471d09a 6117{
51470298 6118 Ssh ssh = (Ssh) handle;
5471d09a 6119 int override_value;
6120
51470298 6121 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
5471d09a 6122 return 0;
6123
6124 /*
6125 * If the SSH socket itself has backed up, add the total backup
6126 * size on that to any individual buffer on the stdin channel.
6127 */
6128 override_value = 0;
51470298 6129 if (ssh->throttled_all)
6130 override_value = ssh->overall_bufsize;
5471d09a 6131
51470298 6132 if (ssh->version == 1) {
5471d09a 6133 return override_value;
51470298 6134 } else if (ssh->version == 2) {
6135 if (!ssh->mainchan || ssh->mainchan->closes > 0)
5471d09a 6136 return override_value;
6137 else
51470298 6138 return (override_value +
6139 bufchain_size(&ssh->mainchan->v.v2.outbuffer));
5471d09a 6140 }
6141
6142 return 0;
374330e2 6143}
6144
6145/*
6e48c3fe 6146 * Called to set the size of the window from SSH's POV.
374330e2 6147 */
51470298 6148static void ssh_size(void *handle, int width, int height)
32874aea 6149{
51470298 6150 Ssh ssh = (Ssh) handle;
6151
6152 ssh->term_width = width;
6153 ssh->term_height = height;
f278d6f8 6154
51470298 6155 switch (ssh->state) {
374330e2 6156 case SSH_STATE_BEFORE_SIZE:
3687d221 6157 case SSH_STATE_PREPACKET:
21248260 6158 case SSH_STATE_CLOSED:
374330e2 6159 break; /* do nothing */
6160 case SSH_STATE_INTERMED:
51470298 6161 ssh->size_needed = TRUE; /* buffer for later */
374330e2 6162 break;
6163 case SSH_STATE_SESSION:
86916870 6164 if (!ssh->cfg.nopty) {
51470298 6165 if (ssh->version == 1) {
6166 send_packet(ssh, SSH1_CMSG_WINDOW_SIZE,
6167 PKT_INT, ssh->term_height,
6168 PKT_INT, ssh->term_width,
32874aea 6169 PKT_INT, 0, PKT_INT, 0, PKT_END);
6170 } else {
51470298 6171 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
6172 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
6173 ssh2_pkt_addstring(ssh, "window-change");
6174 ssh2_pkt_addbool(ssh, 0);
6175 ssh2_pkt_adduint32(ssh, ssh->term_width);
6176 ssh2_pkt_adduint32(ssh, ssh->term_height);
6177 ssh2_pkt_adduint32(ssh, 0);
6178 ssh2_pkt_adduint32(ssh, 0);
6179 ssh2_pkt_send(ssh);
32874aea 6180 }
6181 }
6182 break;
374330e2 6183 }
6184}
6185
6186/*
6abbf9e3 6187 * Send Telnet special codes. TS_EOF is useful for `plink', so you
6188 * can send an EOF and collect resulting output (e.g. `plink
6189 * hostname sort').
374330e2 6190 */
51470298 6191static void ssh_special(void *handle, Telnet_Special code)
32874aea 6192{
51470298 6193 Ssh ssh = (Ssh) handle;
6194
6abbf9e3 6195 if (code == TS_EOF) {
51470298 6196 if (ssh->state != SSH_STATE_SESSION) {
32874aea 6197 /*
6198 * Buffer the EOF in case we are pre-SESSION, so we can
6199 * send it as soon as we reach SESSION.
6200 */
6201 if (code == TS_EOF)
51470298 6202 ssh->eof_needed = TRUE;
32874aea 6203 return;
6204 }
51470298 6205 if (ssh->version == 1) {
6206 send_packet(ssh, SSH1_CMSG_EOF, PKT_END);
32874aea 6207 } else {
51470298 6208 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_EOF);
6209 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
6210 ssh2_pkt_send(ssh);
32874aea 6211 }
6212 logevent("Sent EOF message");
ec55b220 6213 } else if (code == TS_PING) {
51470298 6214 if (ssh->state == SSH_STATE_CLOSED
6215 || ssh->state == SSH_STATE_PREPACKET) return;
6216 if (ssh->version == 1) {
6217 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE))
6218 send_packet(ssh, SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
32874aea 6219 } else {
51470298 6220 ssh2_pkt_init(ssh, SSH2_MSG_IGNORE);
6221 ssh2_pkt_addstring_start(ssh);
6222 ssh2_pkt_send(ssh);
32874aea 6223 }
6abbf9e3 6224 } else {
32874aea 6225 /* do nothing */
6abbf9e3 6226 }
374330e2 6227}
6228
51470298 6229void *new_sock_channel(void *handle, Socket s)
d74d141c 6230{
51470298 6231 Ssh ssh = (Ssh) handle;
d74d141c 6232 struct ssh_channel *c;
6233 c = smalloc(sizeof(struct ssh_channel));
51470298 6234 c->ssh = ssh;
d74d141c 6235
6236 if (c) {
bc240b21 6237 c->remoteid = -1; /* to be set when open confirmed */
51470298 6238 c->localid = alloc_channel_id(ssh);
d74d141c 6239 c->closes = 0;
bc240b21 6240 c->type = CHAN_SOCKDATA_DORMANT;/* identify channel type */
d74d141c 6241 c->u.pfd.s = s;
013dd8c0 6242 bufchain_init(&c->v.v2.outbuffer);
51470298 6243 add234(ssh->channels, c);
d74d141c 6244 }
6245 return c;
6246}
6247
5471d09a 6248/*
6249 * This is called when stdout/stderr (the entity to which
6250 * from_backend sends data) manages to clear some backlog.
6251 */
ae9ae89f 6252static void ssh_unthrottle(void *handle, int bufsize)
5471d09a 6253{
51470298 6254 Ssh ssh = (Ssh) handle;
6255 if (ssh->version == 1) {
6256 if (ssh->v1_stdout_throttling && bufsize < SSH1_BUFFER_LIMIT) {
6257 ssh->v1_stdout_throttling = 0;
6258 ssh1_throttle(ssh, -1);
5471d09a 6259 }
6260 } else {
51470298 6261 if (ssh->mainchan && ssh->mainchan->closes == 0)
6262 ssh2_set_window(ssh->mainchan, OUR_V2_WINSIZE - bufsize);
5471d09a 6263 }
6264}
6265
6b78788a 6266void ssh_send_port_open(void *channel, char *hostname, int port, char *org)
d74d141c 6267{
6268 struct ssh_channel *c = (struct ssh_channel *)channel;
6b78788a 6269 Ssh ssh = c->ssh;
d74d141c 6270
57356d63 6271 logeventf(ssh, "Opening forwarded connection to %s:%d", hostname, port);
d74d141c 6272
51470298 6273 if (ssh->version == 1) {
6274 send_packet(ssh, SSH1_MSG_PORT_OPEN,
bc240b21 6275 PKT_INT, c->localid,
6276 PKT_STR, hostname,
6277 PKT_INT, port,
6278 //PKT_STR, <org:orgport>,
6279 PKT_END);
6280 } else {
51470298 6281 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_OPEN);
6282 ssh2_pkt_addstring(ssh, "direct-tcpip");
6283 ssh2_pkt_adduint32(ssh, c->localid);
5471d09a 6284 c->v.v2.locwindow = OUR_V2_WINSIZE;
51470298 6285 ssh2_pkt_adduint32(ssh, c->v.v2.locwindow);/* our window size */
6286 ssh2_pkt_adduint32(ssh, 0x4000UL); /* our max pkt size */
6287 ssh2_pkt_addstring(ssh, hostname);
6288 ssh2_pkt_adduint32(ssh, port);
bc240b21 6289 /*
6290 * We make up values for the originator data; partly it's
6291 * too much hassle to keep track, and partly I'm not
6292 * convinced the server should be told details like that
6293 * about my local network configuration.
6294 */
51470298 6295 ssh2_pkt_addstring(ssh, "client-side-connection");
6296 ssh2_pkt_adduint32(ssh, 0);
6297 ssh2_pkt_send(ssh);
bc240b21 6298 }
d74d141c 6299}
6300
6301
51470298 6302static Socket ssh_socket(void *handle)
32874aea 6303{
51470298 6304 Ssh ssh = (Ssh) handle;
6305 return ssh->s;
32874aea 6306}
8ccc75b0 6307
51470298 6308static int ssh_sendok(void *handle)
32874aea 6309{
51470298 6310 Ssh ssh = (Ssh) handle;
6311 return ssh->send_ok;
32874aea 6312}
fb09bf1c 6313
51470298 6314static int ssh_ldisc(void *handle, int option)
32874aea 6315{
51470298 6316 Ssh ssh = (Ssh) handle;
32874aea 6317 if (option == LD_ECHO)
51470298 6318 return ssh->echoing;
32874aea 6319 if (option == LD_EDIT)
51470298 6320 return ssh->editing;
0965bee0 6321 return FALSE;
6322}
6323
b9d7bcad 6324static void ssh_provide_ldisc(void *handle, void *ldisc)
6325{
6326 Ssh ssh = (Ssh) handle;
6327 ssh->ldisc = ldisc;
6328}
6329
a8327734 6330static void ssh_provide_logctx(void *handle, void *logctx)
6331{
6332 Ssh ssh = (Ssh) handle;
6333 ssh->logctx = logctx;
6334}
6335
51470298 6336static int ssh_return_exitcode(void *handle)
6337{
6338 Ssh ssh = (Ssh) handle;
6339 return ssh->exitcode;
6340}
6341
6342/*
6343 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
6344 * that fails. This variable is the means by which scp.c can reach
6345 * into the SSH code and find out which one it got.
6346 */
6347extern int ssh_fallback_cmd(void *handle)
d8d6c7e5 6348{
51470298 6349 Ssh ssh = (Ssh) handle;
6350 return ssh->fallback_cmd;
d8d6c7e5 6351}
6352
374330e2 6353Backend ssh_backend = {
6354 ssh_init,
fabd1805 6355 ssh_free,
86916870 6356 ssh_reconfig,
374330e2 6357 ssh_send,
5471d09a 6358 ssh_sendbuffer,
374330e2 6359 ssh_size,
4017be6d 6360 ssh_special,
8ccc75b0 6361 ssh_socket,
d8d6c7e5 6362 ssh_return_exitcode,
97db3be4 6363 ssh_sendok,
0965bee0 6364 ssh_ldisc,
b9d7bcad 6365 ssh_provide_ldisc,
a8327734 6366 ssh_provide_logctx,
5471d09a 6367 ssh_unthrottle,
97db3be4 6368 22
bc240b21 6369};
Local modifications for Simon Tatham's `PuTTY' SSH client and terminal emulator