projects / u / mdw / putty / blame
? search:
summary | shortlog | log | commit | commitdiff | tree
blob | blame (incremental) | history | HEAD
Bah, I left a rogue event log entry lying around.
[u/mdw/putty] / ssh.c
CommitLineData
374330e2 1#include <stdio.h>
2#include <stdlib.h>
fb09bf1c 3#include <stdarg.h>
4#include <assert.h>
374330e2 5
6#include "putty.h"
dacbd0e8 7#include "tree234.h"
fb09bf1c 8#include "ssh.h"
374330e2 9
10#ifndef FALSE
11#define FALSE 0
12#endif
13#ifndef TRUE
14#define TRUE 1
15#endif
16
32874aea 17#define SSH1_MSG_DISCONNECT 1 /* 0x1 */
18#define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
19#define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
20#define SSH1_CMSG_USER 4 /* 0x4 */
21#define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
22#define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
23#define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
24#define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
25#define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
26#define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
27#define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
28#define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
29#define SSH1_SMSG_SUCCESS 14 /* 0xe */
30#define SSH1_SMSG_FAILURE 15 /* 0xf */
31#define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
32#define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
33#define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
34#define SSH1_CMSG_EOF 19 /* 0x13 */
35#define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
36#define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
37#define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
38#define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
39#define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
40#define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
41#define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
42#define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
43#define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
44#define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
45#define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
46#define SSH1_MSG_IGNORE 32 /* 0x20 */
47#define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
48#define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
49#define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
50#define SSH1_MSG_DEBUG 36 /* 0x24 */
51#define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
52#define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
53#define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
54#define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
55#define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
56#define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
57#define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
58
59#define SSH1_AUTH_TIS 5 /* 0x5 */
60#define SSH1_AUTH_CCARD 16 /* 0x10 */
61
62#define SSH1_PROTOFLAG_SCREEN_NUMBER 1 /* 0x1 */
b96dc54c 63/* Mask for protoflags we will echo back to server if seen */
32874aea 64#define SSH1_PROTOFLAGS_SUPPORTED 0 /* 0x1 */
65
66#define SSH2_MSG_DISCONNECT 1 /* 0x1 */
67#define SSH2_MSG_IGNORE 2 /* 0x2 */
68#define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
69#define SSH2_MSG_DEBUG 4 /* 0x4 */
70#define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
71#define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
72#define SSH2_MSG_KEXINIT 20 /* 0x14 */
73#define SSH2_MSG_NEWKEYS 21 /* 0x15 */
74#define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
75#define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
76#define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */
77#define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
78#define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
79#define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
80#define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
81#define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
82#define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
83#define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
84#define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
85#define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
761187b6 86#define SSH2_MSG_USERAUTH_INFO_REQUEST 60 /* 0x3c */
87#define SSH2_MSG_USERAUTH_INFO_RESPONSE 61 /* 0x3d */
32874aea 88#define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
89#define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
90#define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
91#define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
92#define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
93#define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
94#define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
95#define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
96#define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
97#define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
98#define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
99#define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
100#define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
101#define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
102
00db133f 103/*
104 * Packet type contexts, so that ssh2_pkt_type can correctly decode
105 * the ambiguous type numbers back into the correct type strings.
106 */
d1aaf71d 107#define SSH2_PKTCTX_DHGROUP 0x0001
00db133f 108#define SSH2_PKTCTX_DHGEX 0x0002
149d2abc 109#define SSH2_PKTCTX_KEX_MASK 0x000F
00db133f 110#define SSH2_PKTCTX_PUBLICKEY 0x0010
111#define SSH2_PKTCTX_PASSWORD 0x0020
112#define SSH2_PKTCTX_KBDINTER 0x0040
113#define SSH2_PKTCTX_AUTH_MASK 0x00F0
114
32874aea 115#define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
116#define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
117#define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
118#define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
119#define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
120#define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
121#define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
122#define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
123#define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
124#define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
125#define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
126#define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */
127#define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */
128#define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */
129#define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */
38c4a8da 130
131static const char *const ssh2_disconnect_reasons[] = {
132 NULL,
133 "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
134 "SSH_DISCONNECT_PROTOCOL_ERROR",
135 "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
136 "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
137 "SSH_DISCONNECT_MAC_ERROR",
138 "SSH_DISCONNECT_COMPRESSION_ERROR",
139 "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
140 "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
141 "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
142 "SSH_DISCONNECT_CONNECTION_LOST",
143 "SSH_DISCONNECT_BY_APPLICATION",
144 "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
145 "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
146 "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
147 "SSH_DISCONNECT_ILLEGAL_USER_NAME",
148};
9005f3ba 149
32874aea 150#define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
151#define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
152#define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
153#define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
d211621f 154
32874aea 155#define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
fb09bf1c 156
7d503c31 157/*
158 * Various remote-bug flags.
159 */
160#define BUG_CHOKES_ON_SSH1_IGNORE 1
161#define BUG_SSH2_HMAC 2
bd358db1 162#define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
0df73905 163#define BUG_CHOKES_ON_RSA 8
1dd353b5 164#define BUG_SSH2_RSA_PADDING 16
088bde77 165#define BUG_SSH2_DERIVEKEY 32
f382c87d 166#define BUG_SSH2_REKEY 64
dda87a28 167#define BUG_SSH2_PK_SESSIONID 128
bd358db1 168
00db133f 169#define translate(x) if (type == x) return #x
51470298 170#define translatec(x,ctx) if (type == x && (pkt_ctx & ctx)) return #x
ae9ae89f 171static char *ssh1_pkt_type(int type)
00db133f 172{
173 translate(SSH1_MSG_DISCONNECT);
174 translate(SSH1_SMSG_PUBLIC_KEY);
175 translate(SSH1_CMSG_SESSION_KEY);
176 translate(SSH1_CMSG_USER);
177 translate(SSH1_CMSG_AUTH_RSA);
178 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE);
179 translate(SSH1_CMSG_AUTH_RSA_RESPONSE);
180 translate(SSH1_CMSG_AUTH_PASSWORD);
181 translate(SSH1_CMSG_REQUEST_PTY);
182 translate(SSH1_CMSG_WINDOW_SIZE);
183 translate(SSH1_CMSG_EXEC_SHELL);
184 translate(SSH1_CMSG_EXEC_CMD);
185 translate(SSH1_SMSG_SUCCESS);
186 translate(SSH1_SMSG_FAILURE);
187 translate(SSH1_CMSG_STDIN_DATA);
188 translate(SSH1_SMSG_STDOUT_DATA);
189 translate(SSH1_SMSG_STDERR_DATA);
190 translate(SSH1_CMSG_EOF);
191 translate(SSH1_SMSG_EXIT_STATUS);
192 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION);
193 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE);
194 translate(SSH1_MSG_CHANNEL_DATA);
195 translate(SSH1_MSG_CHANNEL_CLOSE);
196 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION);
197 translate(SSH1_SMSG_X11_OPEN);
198 translate(SSH1_CMSG_PORT_FORWARD_REQUEST);
199 translate(SSH1_MSG_PORT_OPEN);
200 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING);
201 translate(SSH1_SMSG_AGENT_OPEN);
202 translate(SSH1_MSG_IGNORE);
203 translate(SSH1_CMSG_EXIT_CONFIRMATION);
204 translate(SSH1_CMSG_X11_REQUEST_FORWARDING);
205 translate(SSH1_CMSG_AUTH_RHOSTS_RSA);
206 translate(SSH1_MSG_DEBUG);
207 translate(SSH1_CMSG_REQUEST_COMPRESSION);
208 translate(SSH1_CMSG_AUTH_TIS);
209 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE);
210 translate(SSH1_CMSG_AUTH_TIS_RESPONSE);
211 translate(SSH1_CMSG_AUTH_CCARD);
212 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE);
213 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE);
214 return "unknown";
215}
ae9ae89f 216static char *ssh2_pkt_type(int pkt_ctx, int type)
00db133f 217{
218 translate(SSH2_MSG_DISCONNECT);
219 translate(SSH2_MSG_IGNORE);
220 translate(SSH2_MSG_UNIMPLEMENTED);
221 translate(SSH2_MSG_DEBUG);
222 translate(SSH2_MSG_SERVICE_REQUEST);
223 translate(SSH2_MSG_SERVICE_ACCEPT);
224 translate(SSH2_MSG_KEXINIT);
225 translate(SSH2_MSG_NEWKEYS);
d1aaf71d 226 translatec(SSH2_MSG_KEXDH_INIT, SSH2_PKTCTX_DHGROUP);
227 translatec(SSH2_MSG_KEXDH_REPLY, SSH2_PKTCTX_DHGROUP);
00db133f 228 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST, SSH2_PKTCTX_DHGEX);
229 translatec(SSH2_MSG_KEX_DH_GEX_GROUP, SSH2_PKTCTX_DHGEX);
230 translatec(SSH2_MSG_KEX_DH_GEX_INIT, SSH2_PKTCTX_DHGEX);
231 translatec(SSH2_MSG_KEX_DH_GEX_REPLY, SSH2_PKTCTX_DHGEX);
232 translate(SSH2_MSG_USERAUTH_REQUEST);
233 translate(SSH2_MSG_USERAUTH_FAILURE);
234 translate(SSH2_MSG_USERAUTH_SUCCESS);
235 translate(SSH2_MSG_USERAUTH_BANNER);
236 translatec(SSH2_MSG_USERAUTH_PK_OK, SSH2_PKTCTX_PUBLICKEY);
237 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, SSH2_PKTCTX_PASSWORD);
238 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST, SSH2_PKTCTX_KBDINTER);
239 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE, SSH2_PKTCTX_KBDINTER);
240 translate(SSH2_MSG_GLOBAL_REQUEST);
241 translate(SSH2_MSG_REQUEST_SUCCESS);
242 translate(SSH2_MSG_REQUEST_FAILURE);
243 translate(SSH2_MSG_CHANNEL_OPEN);
244 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
245 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE);
246 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
247 translate(SSH2_MSG_CHANNEL_DATA);
248 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA);
249 translate(SSH2_MSG_CHANNEL_EOF);
250 translate(SSH2_MSG_CHANNEL_CLOSE);
251 translate(SSH2_MSG_CHANNEL_REQUEST);
252 translate(SSH2_MSG_CHANNEL_SUCCESS);
253 translate(SSH2_MSG_CHANNEL_FAILURE);
254 return "unknown";
255}
256#undef translate
257#undef translatec
7d503c31 258
fb09bf1c 259#define GET_32BIT(cp) \
260 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
261 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
262 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
263 ((unsigned long)(unsigned char)(cp)[3]))
264
265#define PUT_32BIT(cp, value) { \
266 (cp)[0] = (unsigned char)((value) >> 24); \
267 (cp)[1] = (unsigned char)((value) >> 16); \
268 (cp)[2] = (unsigned char)((value) >> 8); \
269 (cp)[3] = (unsigned char)(value); }
270
9a10ecf4 271/* Enumeration values for fields in SSH-1 packets */
272enum {
273 PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR, PKT_BIGNUM,
274 /* These values are for communicating relevant semantics of
275 * fields to the packet logging code. */
276 PKTT_OTHER, PKTT_PASSWORD, PKTT_DATA
277};
972a41c8 278
acddebd9 279/*
280 * Coroutine mechanics for the sillier bits of the code. If these
281 * macros look impenetrable to you, you might find it helpful to
282 * read
283 *
284 * http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
285 *
286 * which explains the theory behind these macros.
b624d1e6 287 *
288 * In particular, if you are getting `case expression not constant'
289 * errors when building with MS Visual Studio, this is because MS's
290 * Edit and Continue debugging feature causes their compiler to
291 * violate ANSI C. To disable Edit and Continue debugging:
292 *
293 * - right-click ssh.c in the FileView
294 * - click Settings
295 * - select the C/C++ tab and the General category
296 * - under `Debug info:', select anything _other_ than `Program
297 * Database for Edit and Continue'.
acddebd9 298 */
51470298 299#define crBegin(v) { int *crLine = &v; switch(v) { case 0:;
300#define crState(t) \
301 struct t *s; \
3d88e64d 302 if (!ssh->t) ssh->t = snew(struct t); \
51470298 303 s = ssh->t;
304#define crFinish(z) } *crLine = 0; return (z); }
305#define crFinishV } *crLine = 0; return; }
374330e2 306#define crReturn(z) \
307 do {\
51470298 308 *crLine =__LINE__; return (z); case __LINE__:;\
374330e2 309 } while (0)
310#define crReturnV \
311 do {\
51470298 312 *crLine=__LINE__; return; case __LINE__:;\
374330e2 313 } while (0)
51470298 314#define crStop(z) do{ *crLine = 0; return (z); }while(0)
315#define crStopV do{ *crLine = 0; return; }while(0)
fb09bf1c 316#define crWaitUntil(c) do { crReturn(0); } while (!(c))
7cca0d81 317#define crWaitUntilV(c) do { crReturnV; } while (!(c))
374330e2 318
51470298 319typedef struct ssh_tag *Ssh;
ff3187f6 320struct Packet;
321
322static struct Packet *ssh2_pkt_init(int pkt_type);
323static void ssh2_pkt_addbool(struct Packet *, unsigned char value);
324static void ssh2_pkt_adduint32(struct Packet *, unsigned long value);
325static void ssh2_pkt_addstring_start(struct Packet *);
326static void ssh2_pkt_addstring_str(struct Packet *, char *data);
327static void ssh2_pkt_addstring_data(struct Packet *, char *data, int len);
328static void ssh2_pkt_addstring(struct Packet *, char *data);
d8baa528 329static unsigned char *ssh2_mpint_fmt(Bignum b, int *len);
ff3187f6 330static void ssh2_pkt_addmp(struct Packet *, Bignum b);
331static int ssh2_pkt_construct(Ssh, struct Packet *);
332static void ssh2_pkt_send(Ssh, struct Packet *);
590f6a5f 333static void ssh2_pkt_send_noqueue(Ssh, struct Packet *);
ff3187f6 334static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen,
335 struct Packet *pktin);
336static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
337 struct Packet *pktin);
3d63ca2e 338
5471d09a 339/*
340 * Buffer management constants. There are several of these for
341 * various different purposes:
342 *
343 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
344 * on a local data stream before we throttle the whole SSH
345 * connection (in SSH1 only). Throttling the whole connection is
346 * pretty drastic so we set this high in the hope it won't
347 * happen very often.
348 *
349 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
350 * on the SSH connection itself before we defensively throttle
351 * _all_ local data streams. This is pretty drastic too (though
352 * thankfully unlikely in SSH2 since the window mechanism should
353 * ensure that the server never has any need to throttle its end
354 * of the connection), so we set this high as well.
355 *
356 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
357 * channels.
358 */
359
360#define SSH1_BUFFER_LIMIT 32768
361#define SSH_MAX_BACKLOG 32768
362#define OUR_V2_WINSIZE 16384
d74d141c 363
85cc02bb 364const static struct ssh_signkey *hostkey_algs[] = { &ssh_rsa, &ssh_dss };
e5574168 365
e0e1a00d 366static void *nullmac_make_context(void)
367{
368 return NULL;
369}
370static void nullmac_free_context(void *handle)
371{
372}
373static void nullmac_key(void *handle, unsigned char *key)
32874aea 374{
375}
e0e1a00d 376static void nullmac_generate(void *handle, unsigned char *blk, int len,
32874aea 377 unsigned long seq)
378{
379}
e0e1a00d 380static int nullmac_verify(void *handle, unsigned char *blk, int len,
381 unsigned long seq)
32874aea 382{
383 return 1;
384}
57476f6b 385const static struct ssh_mac ssh_mac_none = {
e0e1a00d 386 nullmac_make_context, nullmac_free_context, nullmac_key,
387 nullmac_generate, nullmac_verify, "none", 0
e5574168 388};
8b2715b2 389const static struct ssh_mac *macs[] = {
32874aea 390 &ssh_sha1, &ssh_md5, &ssh_mac_none
391};
8b2715b2 392const static struct ssh_mac *buggymacs[] = {
32874aea 393 &ssh_sha1_buggy, &ssh_md5, &ssh_mac_none
394};
e5574168 395
5366aed8 396static void *ssh_comp_none_init(void)
397{
398 return NULL;
399}
400static void ssh_comp_none_cleanup(void *handle)
32874aea 401{
402}
5366aed8 403static int ssh_comp_none_block(void *handle, unsigned char *block, int len,
32874aea 404 unsigned char **outblock, int *outlen)
405{
406 return 0;
407}
5366aed8 408static int ssh_comp_none_disable(void *handle)
32874aea 409{
4ba9b64b 410 return 0;
411}
57476f6b 412const static struct ssh_compress ssh_comp_none = {
4ba9b64b 413 "none",
5366aed8 414 ssh_comp_none_init, ssh_comp_none_cleanup, ssh_comp_none_block,
415 ssh_comp_none_init, ssh_comp_none_cleanup, ssh_comp_none_block,
416 ssh_comp_none_disable, NULL
e5574168 417};
4ba9b64b 418extern const struct ssh_compress ssh_zlib;
419const static struct ssh_compress *compressions[] = {
32874aea 420 &ssh_zlib, &ssh_comp_none
421};
374330e2 422
32874aea 423enum { /* channel types */
783415f8 424 CHAN_MAINSESSION,
425 CHAN_X11,
426 CHAN_AGENT,
bc240b21 427 CHAN_SOCKDATA,
428 CHAN_SOCKDATA_DORMANT /* one the remote hasn't confirmed */
783415f8 429};
430
dacbd0e8 431/*
432 * 2-3-4 tree storing channels.
433 */
434struct ssh_channel {
51470298 435 Ssh ssh; /* pointer back to main context */
d211621f 436 unsigned remoteid, localid;
dacbd0e8 437 int type;
0357890f 438 /*
439 * In SSH1, this value contains four bits:
440 *
441 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
442 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
443 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
444 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
445 *
446 * A channel is completely finished with when all four bits are set.
447 */
dacbd0e8 448 int closes;
5471d09a 449 union {
450 struct ssh1_data_channel {
451 int throttling;
452 } v1;
453 struct ssh2_data_channel {
454 bufchain outbuffer;
455 unsigned remwindow, remmaxpkt;
456 unsigned locwindow;
457 } v2;
458 } v;
dacbd0e8 459 union {
32874aea 460 struct ssh_agent_channel {
461 unsigned char *message;
462 unsigned char msglen[4];
a03c9f9c 463 unsigned lensofar, totallen;
32874aea 464 } a;
465 struct ssh_x11_channel {
466 Socket s;
467 } x11;
d74d141c 468 struct ssh_pfd_channel {
469 Socket s;
470 } pfd;
dacbd0e8 471 } u;
472};
57476f6b 473
d74d141c 474/*
bc240b21 475 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
476 * 2 use this structure in different ways, reflecting SSH 2's
477 * altogether saner approach to port forwarding.
478 *
479 * In SSH 1, you arrange a remote forwarding by sending the server
480 * the remote port number, and the local destination host:port.
481 * When a connection comes in, the server sends you back that
482 * host:port pair, and you connect to it. This is a ready-made
483 * security hole if you're not on the ball: a malicious server
484 * could send you back _any_ host:port pair, so if you trustingly
485 * connect to the address it gives you then you've just opened the
486 * entire inside of your corporate network just by connecting
487 * through it to a dodgy SSH server. Hence, we must store a list of
488 * host:port pairs we _are_ trying to forward to, and reject a
489 * connection request from the server if it's not in the list.
490 *
491 * In SSH 2, each side of the connection minds its own business and
492 * doesn't send unnecessary information to the other. You arrange a
493 * remote forwarding by sending the server just the remote port
494 * number. When a connection comes in, the server tells you which
495 * of its ports was connected to; and _you_ have to remember what
496 * local host:port pair went with that port number.
497 *
06fadff5 498 * Hence, in SSH 1 this structure is indexed by destination
499 * host:port pair, whereas in SSH 2 it is indexed by source port.
d74d141c 500 */
fda2feb1 501struct ssh_portfwd; /* forward declaration */
502
d74d141c 503struct ssh_rportfwd {
bc240b21 504 unsigned sport, dport;
505 char dhost[256];
06fadff5 506 char *sportdesc;
fda2feb1 507 struct ssh_portfwd *pfrec;
d74d141c 508};
fda2feb1 509#define free_rportfwd(pf) ( \
510 ((pf) ? (sfree((pf)->sportdesc)) : (void)0 ), sfree(pf) )
511
512/*
513 * Separately to the rportfwd tree (which is for looking up port
514 * open requests from the server), a tree of _these_ structures is
515 * used to keep track of all the currently open port forwardings,
516 * so that we can reconfigure in mid-session if the user requests
517 * it.
518 */
519struct ssh_portfwd {
84328ddb 520 enum { DESTROY, KEEP, CREATE } status;
fda2feb1 521 int type;
522 unsigned sport, dport;
523 char *saddr, *daddr;
3fe92132 524 char *sserv, *dserv;
fda2feb1 525 struct ssh_rportfwd *remote;
05581745 526 int addressfamily;
fda2feb1 527 void *local;
528};
529#define free_portfwd(pf) ( \
3fe92132 530 ((pf) ? (sfree((pf)->saddr), sfree((pf)->daddr), \
531 sfree((pf)->sserv), sfree((pf)->dserv)) : (void)0 ), sfree(pf) )
d74d141c 532
57476f6b 533struct Packet {
534 long length;
535 int type;
b09eaa88 536 unsigned long sequence;
57476f6b 537 unsigned char *data;
538 unsigned char *body;
539 long savedpos;
540 long maxlen;
9442dd57 541 long encrypted_len; /* for SSH2 total-size counting */
ff3187f6 542
543 /*
544 * State associated with packet logging
545 */
546 int logmode;
547 int nblanks;
548 struct logblank_t *blanks;
57476f6b 549};
550
ff3187f6 551static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen,
552 struct Packet *pktin);
553static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen,
554 struct Packet *pktin);
b09eaa88 555static void ssh1_protocol_setup(Ssh ssh);
556static void ssh2_protocol_setup(Ssh ssh);
51470298 557static void ssh_size(void *handle, int width, int height);
558static void ssh_special(void *handle, Telnet_Special);
5471d09a 559static int ssh2_try_send(struct ssh_channel *c);
51470298 560static void ssh2_add_channel_data(struct ssh_channel *c, char *buf, int len);
561static void ssh_throttle_all(Ssh ssh, int enable, int bufsize);
5471d09a 562static void ssh2_set_window(struct ssh_channel *c, unsigned newwin);
51470298 563static int ssh_sendbuffer(void *handle);
36f94d1f 564static void ssh_do_close(Ssh ssh);
ff3187f6 565static unsigned long ssh_pkt_getuint32(struct Packet *pkt);
566static int ssh2_pkt_getbool(struct Packet *pkt);
567static void ssh_pkt_getstring(struct Packet *pkt, char **p, int *length);
9442dd57 568static void ssh2_timer(void *ctx, long now);
569static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen,
570 struct Packet *pktin);
57476f6b 571
51470298 572struct rdpkt1_state_tag {
57476f6b 573 long len, pad, biglen, to_read;
574 unsigned long realcrc, gotcrc;
575 unsigned char *p;
576 int i;
577 int chunk;
ff3187f6 578 struct Packet *pktin;
51470298 579};
57476f6b 580
51470298 581struct rdpkt2_state_tag {
960e736a 582 long len, pad, payload, packetlen, maclen;
583 int i;
584 int cipherblk;
585 unsigned long incoming_sequence;
ff3187f6 586 struct Packet *pktin;
51470298 587};
588
b09eaa88 589typedef void (*handler_fn_t)(Ssh ssh, struct Packet *pktin);
06fadff5 590typedef void (*chandler_fn_t)(Ssh ssh, struct Packet *pktin, void *ctx);
591
592struct queued_handler;
593struct queued_handler {
594 int msg1, msg2;
595 chandler_fn_t handler;
596 void *ctx;
597 struct queued_handler *next;
598};
b09eaa88 599
51470298 600struct ssh_tag {
601 const struct plug_function_table *fn;
602 /* the above field _must_ be first in the structure */
603
604 SHA_State exhash, exhashbase;
605
606 Socket s;
607
b9d7bcad 608 void *ldisc;
a8327734 609 void *logctx;
b9d7bcad 610
51470298 611 unsigned char session_key[32];
612 int v1_compressing;
613 int v1_remote_protoflags;
614 int v1_local_protoflags;
615 int agentfwd_enabled;
616 int X11_fwd_enabled;
617 int remote_bugs;
618 const struct ssh_cipher *cipher;
371e569c 619 void *v1_cipher_ctx;
0183b242 620 void *crcda_ctx;
51470298 621 const struct ssh2_cipher *cscipher, *sccipher;
371e569c 622 void *cs_cipher_ctx, *sc_cipher_ctx;
51470298 623 const struct ssh_mac *csmac, *scmac;
e0e1a00d 624 void *cs_mac_ctx, *sc_mac_ctx;
51470298 625 const struct ssh_compress *cscomp, *sccomp;
5366aed8 626 void *cs_comp_ctx, *sc_comp_ctx;
51470298 627 const struct ssh_kex *kex;
628 const struct ssh_signkey *hostkey;
629 unsigned char v2_session_id[20];
27cd7fc2 630 void *kex_ctx;
51470298 631
632 char *savedhost;
633 int savedport;
634 int send_ok;
635 int echoing, editing;
636
637 void *frontend;
638
db219738 639 int ospeed, ispeed; /* temporaries */
51470298 640 int term_width, term_height;
641
642 tree234 *channels; /* indexed by local id */
643 struct ssh_channel *mainchan; /* primary session channel */
644 int exitcode;
645
fda2feb1 646 tree234 *rportfwds, *portfwds;
51470298 647
648 enum {
649 SSH_STATE_PREPACKET,
650 SSH_STATE_BEFORE_SIZE,
651 SSH_STATE_INTERMED,
652 SSH_STATE_SESSION,
653 SSH_STATE_CLOSED
654 } state;
655
656 int size_needed, eof_needed;
657
590f6a5f 658 struct Packet **queue;
659 int queuelen, queuesize;
660 int queueing;
51470298 661 unsigned char *deferred_send_data;
662 int deferred_len, deferred_size;
663
664 /*
665 * Gross hack: pscp will try to start SFTP but fall back to
666 * scp1 if that fails. This variable is the means by which
667 * scp.c can reach into the SSH code and find out which one it
668 * got.
669 */
670 int fallback_cmd;
671
672 /*
673 * Used for username and password input.
674 */
675 char *userpass_input_buffer;
676 int userpass_input_buflen;
677 int userpass_input_bufpos;
678 int userpass_input_echo;
679
51470298 680 int pkt_ctx;
681
302121de 682 void *x11auth;
683
51470298 684 int version;
685 int v1_throttle_count;
686 int overall_bufsize;
687 int throttled_all;
688 int v1_stdout_throttling;
689 int v2_outgoing_sequence;
690
691 int ssh1_rdpkt_crstate;
692 int ssh2_rdpkt_crstate;
693 int do_ssh_init_crstate;
694 int ssh_gotdata_crstate;
51470298 695 int do_ssh1_login_crstate;
b09eaa88 696 int do_ssh1_connection_crstate;
51470298 697 int do_ssh2_transport_crstate;
698 int do_ssh2_authconn_crstate;
699
700 void *do_ssh_init_state;
701 void *do_ssh1_login_state;
702 void *do_ssh2_transport_state;
703 void *do_ssh2_authconn_state;
704
705 struct rdpkt1_state_tag rdpkt1_state;
706 struct rdpkt2_state_tag rdpkt2_state;
707
b09eaa88 708 /* ssh1 and ssh2 use this for different things, but both use it */
709 int protocol_initial_phase_done;
710
ff3187f6 711 void (*protocol) (Ssh ssh, unsigned char *in, int inlen,
712 struct Packet *pkt);
713 struct Packet *(*s_rdpkt) (Ssh ssh, unsigned char **data, int *datalen);
86916870 714
715 /*
716 * We maintain a full _copy_ of a Config structure here, not
717 * merely a pointer to it. That way, when we're passed a new
718 * one for reconfiguration, we can check the differences and
719 * potentially reconfigure port forwardings etc in mid-session.
720 */
721 Config cfg;
839f10db 722
723 /*
724 * Used to transfer data back from async agent callbacks.
725 */
726 void *agent_response;
727 int agent_response_len;
b09eaa88 728
729 /*
730 * Dispatch table for packet types that we may have to deal
731 * with at any time.
732 */
733 handler_fn_t packet_dispatch[256];
39934deb 734
735 /*
06fadff5 736 * Queues of one-off handler functions for success/failure
737 * indications from a request.
738 */
739 struct queued_handler *qhead, *qtail;
740
741 /*
39934deb 742 * This module deals with sending keepalives.
743 */
744 Pinger pinger;
9442dd57 745
746 /*
747 * Track incoming and outgoing data sizes and time, for
748 * size-based rekeys.
749 */
750 unsigned long incoming_data_size, outgoing_data_size, deferred_data_size;
d57f70af 751 unsigned long max_data_size;
9442dd57 752 int kex_in_progress;
e6c1536e 753 long next_rekey, last_rekey;
e13bba36 754 char *deferred_rekey_reason; /* points to STATIC string; don't free */
51470298 755};
960e736a 756
382908ad 757#define logevent(s) logevent(ssh->frontend, s)
a8327734 758
759/* logevent, only printf-formatted. */
cbe2d68f 760static void logeventf(Ssh ssh, const char *fmt, ...)
a8327734 761{
762 va_list ap;
57356d63 763 char *buf;
a8327734 764
765 va_start(ap, fmt);
57356d63 766 buf = dupvprintf(fmt, ap);
a8327734 767 va_end(ap);
57356d63 768 logevent(buf);
57356d63 769 sfree(buf);
a8327734 770}
771
6b5cf8b4 772#define bombout(msg) \
773 do { \
774 char *text = dupprintf msg; \
36f94d1f 775 ssh_do_close(ssh); \
6b5cf8b4 776 logevent(text); \
777 connection_fatal(ssh->frontend, "%s", text); \
778 sfree(text); \
779 } while (0)
a8327734 780
9a10ecf4 781/* Functions to leave bits out of the SSH packet log file. */
782
ff3187f6 783static void dont_log_password(Ssh ssh, struct Packet *pkt, int blanktype)
9a10ecf4 784{
785 if (ssh->cfg.logomitpass)
ff3187f6 786 pkt->logmode = blanktype;
9a10ecf4 787}
788
ff3187f6 789static void dont_log_data(Ssh ssh, struct Packet *pkt, int blanktype)
9a10ecf4 790{
791 if (ssh->cfg.logomitdata)
ff3187f6 792 pkt->logmode = blanktype;
9a10ecf4 793}
794
ff3187f6 795static void end_log_omission(Ssh ssh, struct Packet *pkt)
9a10ecf4 796{
ff3187f6 797 pkt->logmode = PKTLOG_EMIT;
9a10ecf4 798}
799
32874aea 800static int ssh_channelcmp(void *av, void *bv)
801{
802 struct ssh_channel *a = (struct ssh_channel *) av;
803 struct ssh_channel *b = (struct ssh_channel *) bv;
804 if (a->localid < b->localid)
805 return -1;
806 if (a->localid > b->localid)
807 return +1;
dacbd0e8 808 return 0;
809}
32874aea 810static int ssh_channelfind(void *av, void *bv)
811{
812 unsigned *a = (unsigned *) av;
813 struct ssh_channel *b = (struct ssh_channel *) bv;
814 if (*a < b->localid)
815 return -1;
816 if (*a > b->localid)
817 return +1;
dacbd0e8 818 return 0;
819}
820
bc240b21 821static int ssh_rportcmp_ssh1(void *av, void *bv)
d74d141c 822{
823 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
824 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
825 int i;
bc240b21 826 if ( (i = strcmp(a->dhost, b->dhost)) != 0)
d74d141c 827 return i < 0 ? -1 : +1;
bc240b21 828 if (a->dport > b->dport)
829 return +1;
830 if (a->dport < b->dport)
831 return -1;
832 return 0;
833}
834
835static int ssh_rportcmp_ssh2(void *av, void *bv)
836{
837 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
838 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
cdcbdf3b 839
bc240b21 840 if (a->sport > b->sport)
d74d141c 841 return +1;
bc240b21 842 if (a->sport < b->sport)
843 return -1;
d74d141c 844 return 0;
845}
846
fda2feb1 847/*
848 * Special form of strcmp which can cope with NULL inputs. NULL is
849 * defined to sort before even the empty string.
850 */
851static int nullstrcmp(const char *a, const char *b)
852{
853 if (a == NULL && b == NULL)
854 return 0;
855 if (a == NULL)
856 return -1;
857 if (b == NULL)
858 return +1;
859 return strcmp(a, b);
860}
861
862static int ssh_portcmp(void *av, void *bv)
863{
864 struct ssh_portfwd *a = (struct ssh_portfwd *) av;
865 struct ssh_portfwd *b = (struct ssh_portfwd *) bv;
866 int i;
867 if (a->type > b->type)
868 return +1;
869 if (a->type < b->type)
870 return -1;
84328ddb 871 if (a->addressfamily > b->addressfamily)
872 return +1;
873 if (a->addressfamily < b->addressfamily)
874 return -1;
fda2feb1 875 if ( (i = nullstrcmp(a->saddr, b->saddr)) != 0)
876 return i < 0 ? -1 : +1;
877 if (a->sport > b->sport)
878 return +1;
879 if (a->sport < b->sport)
880 return -1;
881 if (a->type != 'D') {
882 if ( (i = nullstrcmp(a->daddr, b->daddr)) != 0)
883 return i < 0 ? -1 : +1;
884 if (a->dport > b->dport)
885 return +1;
886 if (a->dport < b->dport)
887 return -1;
888 }
889 return 0;
890}
891
51470298 892static int alloc_channel_id(Ssh ssh)
32874aea 893{
260f3dec 894 const unsigned CHANNEL_NUMBER_OFFSET = 256;
895 unsigned low, high, mid;
d2371c81 896 int tsize;
897 struct ssh_channel *c;
898
899 /*
900 * First-fit allocation of channel numbers: always pick the
901 * lowest unused one. To do this, binary-search using the
902 * counted B-tree to find the largest channel ID which is in a
903 * contiguous sequence from the beginning. (Precisely
904 * everything in that sequence must have ID equal to its tree
905 * index plus CHANNEL_NUMBER_OFFSET.)
906 */
51470298 907 tsize = count234(ssh->channels);
d2371c81 908
32874aea 909 low = -1;
910 high = tsize;
d2371c81 911 while (high - low > 1) {
912 mid = (high + low) / 2;
51470298 913 c = index234(ssh->channels, mid);
d2371c81 914 if (c->localid == mid + CHANNEL_NUMBER_OFFSET)
915 low = mid; /* this one is fine */
916 else
917 high = mid; /* this one is past it */
918 }
919 /*
920 * Now low points to either -1, or the tree index of the
921 * largest ID in the initial sequence.
922 */
923 {
924 unsigned i = low + 1 + CHANNEL_NUMBER_OFFSET;
51470298 925 assert(NULL == find234(ssh->channels, &i, ssh_channelfind));
d2371c81 926 }
927 return low + 1 + CHANNEL_NUMBER_OFFSET;
928}
929
9fab77dc 930static void c_write(Ssh ssh, const char *buf, int len)
32874aea 931{
67779be7 932 if ((flags & FLAG_STDERR)) {
32874aea 933 int i;
934 for (i = 0; i < len; i++)
935 if (buf[i] != '\r')
936 fputc(buf[i], stderr);
fb09bf1c 937 return;
938 }
51470298 939 from_backend(ssh->frontend, 1, buf, len);
3bdaf79d 940}
941
9fab77dc 942static void c_write_untrusted(Ssh ssh, const char *buf, int len)
32874aea 943{
a209e957 944 int i;
945 for (i = 0; i < len; i++) {
32874aea 946 if (buf[i] == '\n')
51470298 947 c_write(ssh, "\r\n", 2);
32874aea 948 else if ((buf[i] & 0x60) || (buf[i] == '\r'))
51470298 949 c_write(ssh, buf + i, 1);
a209e957 950 }
951}
952
9fab77dc 953static void c_write_str(Ssh ssh, const char *buf)
32874aea 954{
51470298 955 c_write(ssh, buf, strlen(buf));
1408a877 956}
957
ff3187f6 958static void ssh_free_packet(struct Packet *pkt)
959{
960 sfree(pkt->data);
961 sfree(pkt);
962}
963static struct Packet *ssh_new_packet(void)
964{
965 struct Packet *pkt = snew(struct Packet);
966
967 pkt->data = NULL;
968 pkt->maxlen = 0;
969 pkt->logmode = PKTLOG_EMIT;
970 pkt->nblanks = 0;
971 pkt->blanks = NULL;
972
973 return pkt;
974}
975
fb09bf1c 976/*
977 * Collect incoming data in the incoming packet buffer.
e5574168 978 * Decipher and verify the packet when it is completely read.
979 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
fb09bf1c 980 * Update the *data and *datalen variables.
ff3187f6 981 * Return a Packet structure when a packet is completed.
fb09bf1c 982 */
ff3187f6 983static struct Packet *ssh1_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
fb09bf1c 984{
51470298 985 struct rdpkt1_state_tag *st = &ssh->rdpkt1_state;
374330e2 986
51470298 987 crBegin(ssh->ssh1_rdpkt_crstate);
374330e2 988
ff3187f6 989 st->pktin = ssh_new_packet();
990
991 st->pktin->type = 0;
992 st->pktin->length = 0;
374330e2 993
57476f6b 994 for (st->i = st->len = 0; st->i < 4; st->i++) {
fb09bf1c 995 while ((*datalen) == 0)
ff3187f6 996 crReturn(NULL);
57476f6b 997 st->len = (st->len << 8) + **data;
fb09bf1c 998 (*data)++, (*datalen)--;
999 }
374330e2 1000
57476f6b 1001 st->pad = 8 - (st->len % 8);
1002 st->biglen = st->len + st->pad;
ff3187f6 1003 st->pktin->length = st->len - 5;
fb09bf1c 1004
ae0500e5 1005 if (st->biglen < 0) {
1006 bombout(("Extremely large packet length from server suggests"
1007 " data stream corruption"));
ff3187f6 1008 ssh_free_packet(st->pktin);
1009 crStop(NULL);
ae0500e5 1010 }
1011
ff3187f6 1012 st->pktin->maxlen = st->biglen;
1013 st->pktin->data = snewn(st->biglen + APIEXTRA, unsigned char);
374330e2 1014
57476f6b 1015 st->to_read = st->biglen;
ff3187f6 1016 st->p = st->pktin->data;
57476f6b 1017 while (st->to_read > 0) {
32874aea 1018 st->chunk = st->to_read;
fb09bf1c 1019 while ((*datalen) == 0)
ff3187f6 1020 crReturn(NULL);
57476f6b 1021 if (st->chunk > (*datalen))
1022 st->chunk = (*datalen);
1023 memcpy(st->p, *data, st->chunk);
1024 *data += st->chunk;
1025 *datalen -= st->chunk;
1026 st->p += st->chunk;
1027 st->to_read -= st->chunk;
fb09bf1c 1028 }
374330e2 1029
ff3187f6 1030 if (ssh->cipher && detect_attack(ssh->crcda_ctx, st->pktin->data,
0183b242 1031 st->biglen, NULL)) {
6b5cf8b4 1032 bombout(("Network attack (CRC compensation) detected!"));
ff3187f6 1033 ssh_free_packet(st->pktin);
1034 crStop(NULL);
9a3a93a5 1035 }
1036
51470298 1037 if (ssh->cipher)
ff3187f6 1038 ssh->cipher->decrypt(ssh->v1_cipher_ctx, st->pktin->data, st->biglen);
374330e2 1039
ff3187f6 1040 st->realcrc = crc32_compute(st->pktin->data, st->biglen - 4);
1041 st->gotcrc = GET_32BIT(st->pktin->data + st->biglen - 4);
57476f6b 1042 if (st->gotcrc != st->realcrc) {
6b5cf8b4 1043 bombout(("Incorrect CRC received on packet"));
ff3187f6 1044 ssh_free_packet(st->pktin);
1045 crStop(NULL);
fb09bf1c 1046 }
572f871e 1047
ff3187f6 1048 st->pktin->body = st->pktin->data + st->pad + 1;
1049 st->pktin->savedpos = 0;
4ba9b64b 1050
51470298 1051 if (ssh->v1_compressing) {
4ba9b64b 1052 unsigned char *decompblk;
1053 int decomplen;
36b8d9bb 1054 if (!zlib_decompress_block(ssh->sc_comp_ctx,
ff3187f6 1055 st->pktin->body - 1, st->pktin->length + 1,
36b8d9bb 1056 &decompblk, &decomplen)) {
1057 bombout(("Zlib decompression encountered invalid data"));
ff3187f6 1058 ssh_free_packet(st->pktin);
1059 crStop(NULL);
36b8d9bb 1060 }
4ba9b64b 1061
ff3187f6 1062 if (st->pktin->maxlen < st->pad + decomplen) {
1063 st->pktin->maxlen = st->pad + decomplen;
1064 st->pktin->data = sresize(st->pktin->data,
1065 st->pktin->maxlen + APIEXTRA,
3d88e64d 1066 unsigned char);
ff3187f6 1067 st->pktin->body = st->pktin->data + st->pad + 1;
4ba9b64b 1068 }
1069
ff3187f6 1070 memcpy(st->pktin->body - 1, decompblk, decomplen);
dcbde236 1071 sfree(decompblk);
ff3187f6 1072 st->pktin->length = decomplen - 1;
4ba9b64b 1073 }
1074
ff3187f6 1075 st->pktin->type = st->pktin->body[-1];
00db133f 1076
9a10ecf4 1077 /*
1078 * Log incoming packet, possibly omitting sensitive fields.
1079 */
1080 if (ssh->logctx) {
1081 int nblanks = 0;
1082 struct logblank_t blank;
1083 if (ssh->cfg.logomitdata) {
1084 int do_blank = FALSE, blank_prefix = 0;
1085 /* "Session data" packets - omit the data field */
ff3187f6 1086 if ((st->pktin->type == SSH1_SMSG_STDOUT_DATA) ||
1087 (st->pktin->type == SSH1_SMSG_STDERR_DATA)) {
9a10ecf4 1088 do_blank = TRUE; blank_prefix = 0;
ff3187f6 1089 } else if (st->pktin->type == SSH1_MSG_CHANNEL_DATA) {
9a10ecf4 1090 do_blank = TRUE; blank_prefix = 4;
1091 }
1092 if (do_blank) {
1093 blank.offset = blank_prefix;
ff3187f6 1094 blank.len = st->pktin->length;
9a10ecf4 1095 blank.type = PKTLOG_OMIT;
1096 nblanks = 1;
1097 }
1098 }
a8327734 1099 log_packet(ssh->logctx,
ff3187f6 1100 PKT_INCOMING, st->pktin->type,
1101 ssh1_pkt_type(st->pktin->type),
1102 st->pktin->body, st->pktin->length,
9a10ecf4 1103 nblanks, &blank);
1104 }
00db133f 1105
ff3187f6 1106 crFinish(st->pktin);
fb09bf1c 1107}
1108
ff3187f6 1109static struct Packet *ssh2_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
e5574168 1110{
51470298 1111 struct rdpkt2_state_tag *st = &ssh->rdpkt2_state;
e5574168 1112
51470298 1113 crBegin(ssh->ssh2_rdpkt_crstate);
e5574168 1114
ff3187f6 1115 st->pktin = ssh_new_packet();
1116
1117 st->pktin->type = 0;
1118 st->pktin->length = 0;
51470298 1119 if (ssh->sccipher)
1120 st->cipherblk = ssh->sccipher->blksize;
e5574168 1121 else
32874aea 1122 st->cipherblk = 8;
960e736a 1123 if (st->cipherblk < 8)
32874aea 1124 st->cipherblk = 8;
960e736a 1125
ff3187f6 1126 st->pktin->data = snewn(st->cipherblk + APIEXTRA, unsigned char);
e5574168 1127
1128 /*
1129 * Acquire and decrypt the first block of the packet. This will
1130 * contain the length and padding details.
1131 */
32874aea 1132 for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) {
e5574168 1133 while ((*datalen) == 0)
ff3187f6 1134 crReturn(NULL);
1135 st->pktin->data[st->i] = *(*data)++;
32874aea 1136 (*datalen)--;
e5574168 1137 }
4252c9cc 1138
51470298 1139 if (ssh->sccipher)
371e569c 1140 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
ff3187f6 1141 st->pktin->data, st->cipherblk);
e5574168 1142
1143 /*
1144 * Now get the length and padding figures.
1145 */
ff3187f6 1146 st->len = GET_32BIT(st->pktin->data);
1147 st->pad = st->pktin->data[4];
e5574168 1148
1149 /*
717dc483 1150 * _Completely_ silly lengths should be stomped on before they
1151 * do us any more damage.
1152 */
1153 if (st->len < 0 || st->pad < 0 || st->len + st->pad < 0) {
6b5cf8b4 1154 bombout(("Incoming packet was garbled on decryption"));
ff3187f6 1155 ssh_free_packet(st->pktin);
1156 crStop(NULL);
717dc483 1157 }
1158
1159 /*
e5574168 1160 * This enables us to deduce the payload length.
1161 */
960e736a 1162 st->payload = st->len - st->pad - 1;
e5574168 1163
ff3187f6 1164 st->pktin->length = st->payload + 5;
e5574168 1165
1166 /*
1167 * So now we can work out the total packet length.
1168 */
960e736a 1169 st->packetlen = st->len + 4;
51470298 1170 st->maclen = ssh->scmac ? ssh->scmac->len : 0;
e5574168 1171
1172 /*
ff3187f6 1173 * Allocate memory for the rest of the packet.
e5574168 1174 */
ff3187f6 1175 st->pktin->maxlen = st->packetlen + st->maclen;
1176 st->pktin->data = sresize(st->pktin->data,
1177 st->pktin->maxlen + APIEXTRA,
1178 unsigned char);
e5574168 1179
1180 /*
1181 * Read and decrypt the remainder of the packet.
1182 */
32874aea 1183 for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen;
1184 st->i++) {
e5574168 1185 while ((*datalen) == 0)
ff3187f6 1186 crReturn(NULL);
1187 st->pktin->data[st->i] = *(*data)++;
32874aea 1188 (*datalen)--;
e5574168 1189 }
1190 /* Decrypt everything _except_ the MAC. */
51470298 1191 if (ssh->sccipher)
371e569c 1192 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
ff3187f6 1193 st->pktin->data + st->cipherblk,
51470298 1194 st->packetlen - st->cipherblk);
e5574168 1195
9442dd57 1196 st->pktin->encrypted_len = st->packetlen;
1197
e5574168 1198 /*
1199 * Check the MAC.
1200 */
51470298 1201 if (ssh->scmac
ff3187f6 1202 && !ssh->scmac->verify(ssh->sc_mac_ctx, st->pktin->data, st->len + 4,
51470298 1203 st->incoming_sequence)) {
6b5cf8b4 1204 bombout(("Incorrect MAC received on packet"));
ff3187f6 1205 ssh_free_packet(st->pktin);
1206 crStop(NULL);
8d5de777 1207 }
b09eaa88 1208
1209 st->pktin->sequence = st->incoming_sequence++;
e5574168 1210
4ba9b64b 1211 /*
1212 * Decompress packet payload.
1213 */
1214 {
1215 unsigned char *newpayload;
1216 int newlen;
51470298 1217 if (ssh->sccomp &&
5366aed8 1218 ssh->sccomp->decompress(ssh->sc_comp_ctx,
ff3187f6 1219 st->pktin->data + 5, st->pktin->length - 5,
51470298 1220 &newpayload, &newlen)) {
ff3187f6 1221 if (st->pktin->maxlen < newlen + 5) {
1222 st->pktin->maxlen = newlen + 5;
1223 st->pktin->data = sresize(st->pktin->data,
1224 st->pktin->maxlen + APIEXTRA,
3d88e64d 1225 unsigned char);
4ba9b64b 1226 }
ff3187f6 1227 st->pktin->length = 5 + newlen;
1228 memcpy(st->pktin->data + 5, newpayload, newlen);
dcbde236 1229 sfree(newpayload);
4ba9b64b 1230 }
1231 }
1232
ff3187f6 1233 st->pktin->savedpos = 6;
1234 st->pktin->body = st->pktin->data;
1235 st->pktin->type = st->pktin->data[5];
e5574168 1236
9a10ecf4 1237 /*
1238 * Log incoming packet, possibly omitting sensitive fields.
1239 */
1240 if (ssh->logctx) {
1241 int nblanks = 0;
1242 struct logblank_t blank;
1243 if (ssh->cfg.logomitdata) {
1244 int do_blank = FALSE, blank_prefix = 0;
1245 /* "Session data" packets - omit the data field */
ff3187f6 1246 if (st->pktin->type == SSH2_MSG_CHANNEL_DATA) {
9a10ecf4 1247 do_blank = TRUE; blank_prefix = 4;
ff3187f6 1248 } else if (st->pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
9a10ecf4 1249 do_blank = TRUE; blank_prefix = 8;
1250 }
1251 if (do_blank) {
1252 blank.offset = blank_prefix;
ff3187f6 1253 blank.len = (st->pktin->length-6) - blank_prefix;
9a10ecf4 1254 blank.type = PKTLOG_OMIT;
1255 nblanks = 1;
1256 }
1257 }
ff3187f6 1258 log_packet(ssh->logctx, PKT_INCOMING, st->pktin->type,
1259 ssh2_pkt_type(ssh->pkt_ctx, st->pktin->type),
1260 st->pktin->data+6, st->pktin->length-6,
9a10ecf4 1261 nblanks, &blank);
1262 }
00db133f 1263
ff3187f6 1264 crFinish(st->pktin);
e5574168 1265}
1266
ff3187f6 1267static void ssh1_pktout_size(struct Packet *pkt, int len)
32874aea 1268{
374330e2 1269 int pad, biglen;
1270
1271 len += 5; /* type and CRC */
32874aea 1272 pad = 8 - (len % 8);
374330e2 1273 biglen = len + pad;
1274
ff3187f6 1275 pkt->length = len - 5;
1276 if (pkt->maxlen < biglen) {
1277 pkt->maxlen = biglen;
1278 pkt->data = sresize(pkt->data, biglen + 4 + APIEXTRA, unsigned char);
374330e2 1279 }
ff3187f6 1280 pkt->body = pkt->data + 4 + pad + 1;
4ba9b64b 1281}
374330e2 1282
ff3187f6 1283static struct Packet *s_wrpkt_start(int type, int len)
32874aea 1284{
ff3187f6 1285 struct Packet *pkt = ssh_new_packet();
1286 ssh1_pktout_size(pkt, len);
1287 pkt->type = type;
9a10ecf4 1288 /* Initialise log omission state */
ff3187f6 1289 pkt->nblanks = 0;
1290 pkt->blanks = NULL;
1291 return pkt;
374330e2 1292}
1293
ff3187f6 1294static int s_wrpkt_prepare(Ssh ssh, struct Packet *pkt)
32874aea 1295{
fd7a4aad 1296 int pad, biglen, i;
374330e2 1297 unsigned long crc;
fd7a4aad 1298#ifdef __SC__
1299 /*
1300 * XXX various versions of SC (including 8.8.4) screw up the
1301 * register allocation in this function and use the same register
1302 * (D6) for len and as a temporary, with predictable results. The
1303 * following sledgehammer prevents this.
1304 */
1305 volatile
1306#endif
1307 int len;
374330e2 1308
ff3187f6 1309 pkt->body[-1] = pkt->type;
4ba9b64b 1310
a8327734 1311 if (ssh->logctx)
ff3187f6 1312 log_packet(ssh->logctx, PKT_OUTGOING, pkt->type,
1313 ssh1_pkt_type(pkt->type),
1314 pkt->body, pkt->length,
1315 pkt->nblanks, pkt->blanks);
1316 sfree(pkt->blanks); pkt->blanks = NULL;
1317 pkt->nblanks = 0;
00db133f 1318
51470298 1319 if (ssh->v1_compressing) {
4ba9b64b 1320 unsigned char *compblk;
1321 int complen;
5366aed8 1322 zlib_compress_block(ssh->cs_comp_ctx,
ff3187f6 1323 pkt->body - 1, pkt->length + 1,
4ba9b64b 1324 &compblk, &complen);
ff3187f6 1325 ssh1_pktout_size(pkt, complen - 1);
1326 memcpy(pkt->body - 1, compblk, complen);
dcbde236 1327 sfree(compblk);
4ba9b64b 1328 }
1329
ff3187f6 1330 len = pkt->length + 5; /* type and CRC */
32874aea 1331 pad = 8 - (len % 8);
374330e2 1332 biglen = len + pad;
1333
32874aea 1334 for (i = 0; i < pad; i++)
ff3187f6 1335 pkt->data[i + 4] = random_byte();
1336 crc = crc32_compute(pkt->data + 4, biglen - 4);
1337 PUT_32BIT(pkt->data + biglen, crc);
1338 PUT_32BIT(pkt->data, len);
374330e2 1339
51470298 1340 if (ssh->cipher)
ff3187f6 1341 ssh->cipher->encrypt(ssh->v1_cipher_ctx, pkt->data + 4, biglen);
374330e2 1342
32874aea 1343 return biglen + 4;
39065bed 1344}
1345
ff3187f6 1346static void s_wrpkt(Ssh ssh, struct Packet *pkt)
32874aea 1347{
5471d09a 1348 int len, backlog;
ff3187f6 1349 len = s_wrpkt_prepare(ssh, pkt);
1350 backlog = sk_write(ssh->s, (char *)pkt->data, len);
5471d09a 1351 if (backlog > SSH_MAX_BACKLOG)
51470298 1352 ssh_throttle_all(ssh, 1, backlog);
39065bed 1353}
1354
ff3187f6 1355static void s_wrpkt_defer(Ssh ssh, struct Packet *pkt)
32874aea 1356{
39065bed 1357 int len;
ff3187f6 1358 len = s_wrpkt_prepare(ssh, pkt);
51470298 1359 if (ssh->deferred_len + len > ssh->deferred_size) {
1360 ssh->deferred_size = ssh->deferred_len + len + 128;
3d88e64d 1361 ssh->deferred_send_data = sresize(ssh->deferred_send_data,
1362 ssh->deferred_size,
1363 unsigned char);
39065bed 1364 }
ff3187f6 1365 memcpy(ssh->deferred_send_data + ssh->deferred_len, pkt->data, len);
51470298 1366 ssh->deferred_len += len;
374330e2 1367}
1368
fb09bf1c 1369/*
39065bed 1370 * Construct a packet with the specified contents.
fb09bf1c 1371 */
ff3187f6 1372static struct Packet *construct_packet(Ssh ssh, int pkttype,
1373 va_list ap1, va_list ap2)
fb09bf1c 1374{
fb09bf1c 1375 unsigned char *p, *argp, argchar;
1376 unsigned long argint;
1377 int pktlen, argtype, arglen;
7cca0d81 1378 Bignum bn;
ff3187f6 1379 struct Packet *pkt;
fb09bf1c 1380
1381 pktlen = 0;
39065bed 1382 while ((argtype = va_arg(ap1, int)) != PKT_END) {
fb09bf1c 1383 switch (argtype) {
1384 case PKT_INT:
39065bed 1385 (void) va_arg(ap1, int);
fb09bf1c 1386 pktlen += 4;
1387 break;
1388 case PKT_CHAR:
1ec39246 1389 (void) va_arg(ap1, int);
fb09bf1c 1390 pktlen++;
1391 break;
1392 case PKT_DATA:
39065bed 1393 (void) va_arg(ap1, unsigned char *);
1394 arglen = va_arg(ap1, int);
fb09bf1c 1395 pktlen += arglen;
1396 break;
1397 case PKT_STR:
39065bed 1398 argp = va_arg(ap1, unsigned char *);
d8baa528 1399 arglen = strlen((char *)argp);
fb09bf1c 1400 pktlen += 4 + arglen;
1401 break;
7cca0d81 1402 case PKT_BIGNUM:
39065bed 1403 bn = va_arg(ap1, Bignum);
32874aea 1404 pktlen += ssh1_bignum_length(bn);
7cca0d81 1405 break;
9a10ecf4 1406 case PKTT_PASSWORD:
1407 case PKTT_DATA:
1408 case PKTT_OTHER:
1409 /* ignore this pass */
1410 break;
fb09bf1c 1411 default:
1412 assert(0);
1413 }
1414 }
fb09bf1c 1415
ff3187f6 1416 pkt = s_wrpkt_start(pkttype, pktlen);
1417 p = pkt->body;
fb09bf1c 1418
39065bed 1419 while ((argtype = va_arg(ap2, int)) != PKT_END) {
ff3187f6 1420 int offset = p - pkt->body, len = 0;
fb09bf1c 1421 switch (argtype) {
9a10ecf4 1422 /* Actual fields in the packet */
fb09bf1c 1423 case PKT_INT:
39065bed 1424 argint = va_arg(ap2, int);
fb09bf1c 1425 PUT_32BIT(p, argint);
9a10ecf4 1426 len = 4;
fb09bf1c 1427 break;
1428 case PKT_CHAR:
1ec39246 1429 argchar = (unsigned char) va_arg(ap2, int);
fb09bf1c 1430 *p = argchar;
9a10ecf4 1431 len = 1;
fb09bf1c 1432 break;
1433 case PKT_DATA:
39065bed 1434 argp = va_arg(ap2, unsigned char *);
1435 arglen = va_arg(ap2, int);
fb09bf1c 1436 memcpy(p, argp, arglen);
9a10ecf4 1437 len = arglen;
fb09bf1c 1438 break;
1439 case PKT_STR:
39065bed 1440 argp = va_arg(ap2, unsigned char *);
d8baa528 1441 arglen = strlen((char *)argp);
fb09bf1c 1442 PUT_32BIT(p, arglen);
1443 memcpy(p + 4, argp, arglen);
9a10ecf4 1444 len = arglen + 4;
fb09bf1c 1445 break;
7cca0d81 1446 case PKT_BIGNUM:
39065bed 1447 bn = va_arg(ap2, Bignum);
9a10ecf4 1448 len = ssh1_write_bignum(p, bn);
1449 break;
1450 /* Tokens for modifications to packet logging */
1451 case PKTT_PASSWORD:
ff3187f6 1452 dont_log_password(ssh, pkt, PKTLOG_BLANK);
9a10ecf4 1453 break;
1454 case PKTT_DATA:
ff3187f6 1455 dont_log_data(ssh, pkt, PKTLOG_OMIT);
7cca0d81 1456 break;
9a10ecf4 1457 case PKTT_OTHER:
ff3187f6 1458 end_log_omission(ssh, pkt);
9a10ecf4 1459 break;
1460 }
1461 p += len;
1462 /* Deal with logfile omission, if required. */
ff3187f6 1463 if (len && (pkt->logmode != PKTLOG_EMIT)) {
1464 pkt->nblanks++;
1465 pkt->blanks = sresize(pkt->blanks, pkt->nblanks,
1466 struct logblank_t);
1467 pkt->blanks[pkt->nblanks-1].offset = offset;
1468 pkt->blanks[pkt->nblanks-1].len = len;
1469 pkt->blanks[pkt->nblanks-1].type = pkt->logmode;
fb09bf1c 1470 }
1471 }
ff3187f6 1472
1473 return pkt;
39065bed 1474}
fb09bf1c 1475
51470298 1476static void send_packet(Ssh ssh, int pkttype, ...)
32874aea 1477{
ff3187f6 1478 struct Packet *pkt;
39065bed 1479 va_list ap1, ap2;
1480 va_start(ap1, pkttype);
1481 va_start(ap2, pkttype);
ff3187f6 1482 pkt = construct_packet(ssh, pkttype, ap1, ap2);
1483 va_end(ap2);
1484 va_end(ap1);
1485 s_wrpkt(ssh, pkt);
1486 ssh_free_packet(pkt);
fb09bf1c 1487}
1488
51470298 1489static void defer_packet(Ssh ssh, int pkttype, ...)
32874aea 1490{
ff3187f6 1491 struct Packet *pkt;
39065bed 1492 va_list ap1, ap2;
1493 va_start(ap1, pkttype);
1494 va_start(ap2, pkttype);
ff3187f6 1495 pkt = construct_packet(ssh, pkttype, ap1, ap2);
1496 va_end(ap2);
1497 va_end(ap1);
1498 s_wrpkt_defer(ssh, pkt);
1499 ssh_free_packet(pkt);
39065bed 1500}
1501
32874aea 1502static int ssh_versioncmp(char *a, char *b)
1503{
9697bfd2 1504 char *ae, *be;
1505 unsigned long av, bv;
1506
43aa02a7 1507 av = strtoul(a, &ae, 10);
1508 bv = strtoul(b, &be, 10);
32874aea 1509 if (av != bv)
1510 return (av < bv ? -1 : +1);
1511 if (*ae == '.')
1512 ae++;
1513 if (*be == '.')
1514 be++;
43aa02a7 1515 av = strtoul(ae, &ae, 10);
1516 bv = strtoul(be, &be, 10);
32874aea 1517 if (av != bv)
1518 return (av < bv ? -1 : +1);
9697bfd2 1519 return 0;
1520}
1521
e5574168 1522/*
a92dd380 1523 * Utility routines for putting an SSH-protocol `string' and
1524 * `uint32' into a SHA state.
e5574168 1525 */
1526#include <stdio.h>
32874aea 1527static void sha_string(SHA_State * s, void *str, int len)
1528{
e5574168 1529 unsigned char lenblk[4];
e5574168 1530 PUT_32BIT(lenblk, len);
e5574168 1531 SHA_Bytes(s, lenblk, 4);
e5574168 1532 SHA_Bytes(s, str, len);
1533}
1534
32874aea 1535static void sha_uint32(SHA_State * s, unsigned i)
1536{
a92dd380 1537 unsigned char intblk[4];
1538 PUT_32BIT(intblk, i);
1539 SHA_Bytes(s, intblk, 4);
1540}
1541
7cca0d81 1542/*
1543 * SSH2 packet construction functions.
1544 */
ff3187f6 1545static void ssh2_pkt_ensure(struct Packet *pkt, int length)
32874aea 1546{
ff3187f6 1547 if (pkt->maxlen < length) {
1548 pkt->maxlen = length + 256;
1549 pkt->data = sresize(pkt->data, pkt->maxlen + APIEXTRA, unsigned char);
7cca0d81 1550 }
783415f8 1551}
ff3187f6 1552static void ssh2_pkt_adddata(struct Packet *pkt, void *data, int len)
32874aea 1553{
ff3187f6 1554 if (pkt->logmode != PKTLOG_EMIT) {
1555 pkt->nblanks++;
1556 pkt->blanks = sresize(pkt->blanks, pkt->nblanks, struct logblank_t);
1557 pkt->blanks[pkt->nblanks-1].offset = pkt->length - 6;
1558 pkt->blanks[pkt->nblanks-1].len = len;
1559 pkt->blanks[pkt->nblanks-1].type = pkt->logmode;
1560 }
1561 pkt->length += len;
1562 ssh2_pkt_ensure(pkt, pkt->length);
1563 memcpy(pkt->data + pkt->length - len, data, len);
7cca0d81 1564}
ff3187f6 1565static void ssh2_pkt_addbyte(struct Packet *pkt, unsigned char byte)
32874aea 1566{
ff3187f6 1567 ssh2_pkt_adddata(pkt, &byte, 1);
7cca0d81 1568}
ff3187f6 1569static struct Packet *ssh2_pkt_init(int pkt_type)
32874aea 1570{
ff3187f6 1571 struct Packet *pkt = ssh_new_packet();
1572 pkt->length = 5;
1573 ssh2_pkt_addbyte(pkt, (unsigned char) pkt_type);
1574 return pkt;
7cca0d81 1575}
ff3187f6 1576static void ssh2_pkt_addbool(struct Packet *pkt, unsigned char value)
32874aea 1577{
ff3187f6 1578 ssh2_pkt_adddata(pkt, &value, 1);
7cca0d81 1579}
ff3187f6 1580static void ssh2_pkt_adduint32(struct Packet *pkt, unsigned long value)
32874aea 1581{
7cca0d81 1582 unsigned char x[4];
1583 PUT_32BIT(x, value);
ff3187f6 1584 ssh2_pkt_adddata(pkt, x, 4);
7cca0d81 1585}
ff3187f6 1586static void ssh2_pkt_addstring_start(struct Packet *pkt)
32874aea 1587{
ff3187f6 1588 ssh2_pkt_adduint32(pkt, 0);
1589 pkt->savedpos = pkt->length;
7cca0d81 1590}
ff3187f6 1591static void ssh2_pkt_addstring_str(struct Packet *pkt, char *data)
32874aea 1592{
ff3187f6 1593 ssh2_pkt_adddata(pkt, data, strlen(data));
1594 PUT_32BIT(pkt->data + pkt->savedpos - 4, pkt->length - pkt->savedpos);
7cca0d81 1595}
ff3187f6 1596static void ssh2_pkt_addstring_data(struct Packet *pkt, char *data, int len)
32874aea 1597{
ff3187f6 1598 ssh2_pkt_adddata(pkt, data, len);
1599 PUT_32BIT(pkt->data + pkt->savedpos - 4, pkt->length - pkt->savedpos);
7cca0d81 1600}
ff3187f6 1601static void ssh2_pkt_addstring(struct Packet *pkt, char *data)
32874aea 1602{
ff3187f6 1603 ssh2_pkt_addstring_start(pkt);
1604 ssh2_pkt_addstring_str(pkt, data);
7cca0d81 1605}
d8baa528 1606static unsigned char *ssh2_mpint_fmt(Bignum b, int *len)
32874aea 1607{
7cca0d81 1608 unsigned char *p;
32874aea 1609 int i, n = (bignum_bitcount(b) + 7) / 8;
3d88e64d 1610 p = snewn(n + 1, unsigned char);
7cca0d81 1611 if (!p)
32874aea 1612 fatalbox("out of memory");
7cca0d81 1613 p[0] = 0;
3709bfe9 1614 for (i = 1; i <= n; i++)
32874aea 1615 p[i] = bignum_byte(b, n - i);
7cca0d81 1616 i = 0;
32874aea 1617 while (i <= n && p[i] == 0 && (p[i + 1] & 0x80) == 0)
1618 i++;
1619 memmove(p, p + i, n + 1 - i);
1620 *len = n + 1 - i;
7cca0d81 1621 return p;
1622}
ff3187f6 1623static void ssh2_pkt_addmp(struct Packet *pkt, Bignum b)
32874aea 1624{
7cca0d81 1625 unsigned char *p;
1626 int len;
1627 p = ssh2_mpint_fmt(b, &len);
ff3187f6 1628 ssh2_pkt_addstring_start(pkt);
1629 ssh2_pkt_addstring_data(pkt, (char *)p, len);
dcbde236 1630 sfree(p);
7cca0d81 1631}
b185170a 1632
1633/*
1634 * Construct an SSH2 final-form packet: compress it, encrypt it,
1635 * put the MAC on it. Final packet, ready to be sent, is stored in
ff3187f6 1636 * pkt->data. Total length is returned.
b185170a 1637 */
ff3187f6 1638static int ssh2_pkt_construct(Ssh ssh, struct Packet *pkt)
32874aea 1639{
7cca0d81 1640 int cipherblk, maclen, padding, i;
7cca0d81 1641
a8327734 1642 if (ssh->logctx)
ff3187f6 1643 log_packet(ssh->logctx, PKT_OUTGOING, pkt->data[5],
1644 ssh2_pkt_type(ssh->pkt_ctx, pkt->data[5]),
1645 pkt->data + 6, pkt->length - 6,
1646 pkt->nblanks, pkt->blanks);
1647 sfree(pkt->blanks); pkt->blanks = NULL;
1648 pkt->nblanks = 0;
00db133f 1649
7cca0d81 1650 /*
4ba9b64b 1651 * Compress packet payload.
1652 */
4ba9b64b 1653 {
1654 unsigned char *newpayload;
1655 int newlen;
51470298 1656 if (ssh->cscomp &&
ff3187f6 1657 ssh->cscomp->compress(ssh->cs_comp_ctx, pkt->data + 5,
1658 pkt->length - 5,
51470298 1659 &newpayload, &newlen)) {
ff3187f6 1660 pkt->length = 5;
1661 ssh2_pkt_adddata(pkt, newpayload, newlen);
dcbde236 1662 sfree(newpayload);
4ba9b64b 1663 }
1664 }
1665
1666 /*
7cca0d81 1667 * Add padding. At least four bytes, and must also bring total
1668 * length (minus MAC) up to a multiple of the block size.
1669 */
51470298 1670 cipherblk = ssh->cscipher ? ssh->cscipher->blksize : 8; /* block size */
32874aea 1671 cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
7cca0d81 1672 padding = 4;
32874aea 1673 padding +=
ff3187f6 1674 (cipherblk - (pkt->length + padding) % cipherblk) % cipherblk;
51470298 1675 maclen = ssh->csmac ? ssh->csmac->len : 0;
ff3187f6 1676 ssh2_pkt_ensure(pkt, pkt->length + padding + maclen);
1677 pkt->data[4] = padding;
7cca0d81 1678 for (i = 0; i < padding; i++)
ff3187f6 1679 pkt->data[pkt->length + i] = random_byte();
1680 PUT_32BIT(pkt->data, pkt->length + padding - 4);
51470298 1681 if (ssh->csmac)
ff3187f6 1682 ssh->csmac->generate(ssh->cs_mac_ctx, pkt->data,
1683 pkt->length + padding,
51470298 1684 ssh->v2_outgoing_sequence);
1685 ssh->v2_outgoing_sequence++; /* whether or not we MACed */
1686
1687 if (ssh->cscipher)
371e569c 1688 ssh->cscipher->encrypt(ssh->cs_cipher_ctx,
ff3187f6 1689 pkt->data, pkt->length + padding);
51470298 1690
9442dd57 1691 pkt->encrypted_len = pkt->length + padding;
1692
ff3187f6 1693 /* Ready-to-send packet starts at pkt->data. We return length. */
1694 return pkt->length + padding + maclen;
b185170a 1695}
1696
1697/*
590f6a5f 1698 * Routines called from the main SSH code to send packets. There
1699 * are quite a few of these, because we have two separate
1700 * mechanisms for delaying the sending of packets:
1701 *
1702 * - In order to send an IGNORE message and a password message in
1703 * a single fixed-length blob, we require the ability to
1704 * concatenate the encrypted forms of those two packets _into_ a
1705 * single blob and then pass it to our <network.h> transport
1706 * layer in one go. Hence, there's a deferment mechanism which
1707 * works after packet encryption.
1708 *
1709 * - In order to avoid sending any connection-layer messages
1710 * during repeat key exchange, we have to queue up any such
1711 * outgoing messages _before_ they are encrypted (and in
1712 * particular before they're allocated sequence numbers), and
1713 * then send them once we've finished.
1714 *
1715 * I call these mechanisms `defer' and `queue' respectively, so as
1716 * to distinguish them reasonably easily.
1717 *
1718 * The functions send_noqueue() and defer_noqueue() free the packet
1719 * structure they are passed. Every outgoing packet goes through
1720 * precisely one of these functions in its life; packets passed to
1721 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1722 * these or get queued, and then when the queue is later emptied
1723 * the packets are all passed to defer_noqueue().
b185170a 1724 */
590f6a5f 1725
1726/*
1727 * Send an SSH2 packet immediately, without queuing or deferring.
1728 */
1729static void ssh2_pkt_send_noqueue(Ssh ssh, struct Packet *pkt)
32874aea 1730{
5471d09a 1731 int len;
1732 int backlog;
ff3187f6 1733 len = ssh2_pkt_construct(ssh, pkt);
1734 backlog = sk_write(ssh->s, (char *)pkt->data, len);
5471d09a 1735 if (backlog > SSH_MAX_BACKLOG)
51470298 1736 ssh_throttle_all(ssh, 1, backlog);
9442dd57 1737
1738 ssh->outgoing_data_size += pkt->encrypted_len;
1739 if (!ssh->kex_in_progress &&
d57f70af 1740 ssh->max_data_size != 0 &&
1741 ssh->outgoing_data_size > ssh->max_data_size)
f382c87d 1742 do_ssh2_transport(ssh, "too much data sent", -1, NULL);
9442dd57 1743
ff3187f6 1744 ssh_free_packet(pkt);
b185170a 1745}
1746
1747/*
590f6a5f 1748 * Defer an SSH2 packet.
b185170a 1749 */
590f6a5f 1750static void ssh2_pkt_defer_noqueue(Ssh ssh, struct Packet *pkt)
32874aea 1751{
ff3187f6 1752 int len = ssh2_pkt_construct(ssh, pkt);
51470298 1753 if (ssh->deferred_len + len > ssh->deferred_size) {
1754 ssh->deferred_size = ssh->deferred_len + len + 128;
3d88e64d 1755 ssh->deferred_send_data = sresize(ssh->deferred_send_data,
1756 ssh->deferred_size,
1757 unsigned char);
b185170a 1758 }
ff3187f6 1759 memcpy(ssh->deferred_send_data + ssh->deferred_len, pkt->data, len);
51470298 1760 ssh->deferred_len += len;
9442dd57 1761 ssh->deferred_data_size += pkt->encrypted_len;
ff3187f6 1762 ssh_free_packet(pkt);
b185170a 1763}
1764
1765/*
590f6a5f 1766 * Queue an SSH2 packet.
1767 */
1768static void ssh2_pkt_queue(Ssh ssh, struct Packet *pkt)
1769{
1770 assert(ssh->queueing);
1771
1772 if (ssh->queuelen >= ssh->queuesize) {
1773 ssh->queuesize = ssh->queuelen + 32;
1774 ssh->queue = sresize(ssh->queue, ssh->queuesize, struct Packet *);
1775 }
1776
1777 ssh->queue[ssh->queuelen++] = pkt;
1778}
1779
1780/*
1781 * Either queue or send a packet, depending on whether queueing is
1782 * set.
1783 */
1784static void ssh2_pkt_send(Ssh ssh, struct Packet *pkt)
1785{
1786 if (ssh->queueing)
1787 ssh2_pkt_queue(ssh, pkt);
1788 else
1789 ssh2_pkt_send_noqueue(ssh, pkt);
1790}
1791
1792/*
1793 * Either queue or defer a packet, depending on whether queueing is
1794 * set.
1795 */
1796static void ssh2_pkt_defer(Ssh ssh, struct Packet *pkt)
1797{
1798 if (ssh->queueing)
1799 ssh2_pkt_queue(ssh, pkt);
1800 else
1801 ssh2_pkt_defer_noqueue(ssh, pkt);
1802}
1803
1804/*
b185170a 1805 * Send the whole deferred data block constructed by
39065bed 1806 * ssh2_pkt_defer() or SSH1's defer_packet().
590f6a5f 1807 *
1808 * The expected use of the defer mechanism is that you call
1809 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1810 * not currently queueing, this simply sets up deferred_send_data
1811 * and then sends it. If we _are_ currently queueing, the calls to
1812 * ssh2_pkt_defer() put the deferred packets on to the queue
1813 * instead, and therefore ssh_pkt_defersend() has no deferred data
1814 * to send. Hence, there's no need to make it conditional on
1815 * ssh->queueing.
b185170a 1816 */
51470298 1817static void ssh_pkt_defersend(Ssh ssh)
32874aea 1818{
5471d09a 1819 int backlog;
d8baa528 1820 backlog = sk_write(ssh->s, (char *)ssh->deferred_send_data,
1821 ssh->deferred_len);
51470298 1822 ssh->deferred_len = ssh->deferred_size = 0;
1823 sfree(ssh->deferred_send_data);
1824 ssh->deferred_send_data = NULL;
5471d09a 1825 if (backlog > SSH_MAX_BACKLOG)
51470298 1826 ssh_throttle_all(ssh, 1, backlog);
9442dd57 1827
1828 ssh->outgoing_data_size += ssh->deferred_data_size;
1829 if (!ssh->kex_in_progress &&
d57f70af 1830 ssh->max_data_size != 0 &&
1831 ssh->outgoing_data_size > ssh->max_data_size)
f382c87d 1832 do_ssh2_transport(ssh, "too much data sent", -1, NULL);
9442dd57 1833 ssh->deferred_data_size = 0;
7cca0d81 1834}
1835
590f6a5f 1836/*
1837 * Send all queued SSH2 packets. We send them by means of
1838 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1839 * packets that needed to be lumped together.
1840 */
1841static void ssh2_pkt_queuesend(Ssh ssh)
1842{
1843 int i;
1844
1845 assert(!ssh->queueing);
1846
1847 for (i = 0; i < ssh->queuelen; i++)
1848 ssh2_pkt_defer_noqueue(ssh, ssh->queue[i]);
1849 ssh->queuelen = 0;
1850
1851 ssh_pkt_defersend(ssh);
1852}
1853
7cca0d81 1854#if 0
32874aea 1855void bndebug(char *string, Bignum b)
1856{
7cca0d81 1857 unsigned char *p;
1858 int i, len;
1859 p = ssh2_mpint_fmt(b, &len);
1860 debug(("%s", string));
1861 for (i = 0; i < len; i++)
32874aea 1862 debug((" %02x", p[i]));
765c4200 1863 debug(("\n"));
dcbde236 1864 sfree(p);
7cca0d81 1865}
1866#endif
1867
32874aea 1868static void sha_mpint(SHA_State * s, Bignum b)
1869{
7cca0d81 1870 unsigned char *p;
1871 int len;
1872 p = ssh2_mpint_fmt(b, &len);
1873 sha_string(s, p, len);
dcbde236 1874 sfree(p);
7cca0d81 1875}
1876
1877/*
0016d70b 1878 * Packet decode functions for both SSH1 and SSH2.
7cca0d81 1879 */
ff3187f6 1880static unsigned long ssh_pkt_getuint32(struct Packet *pkt)
32874aea 1881{
7cca0d81 1882 unsigned long value;
ff3187f6 1883 if (pkt->length - pkt->savedpos < 4)
32874aea 1884 return 0; /* arrgh, no way to decline (FIXME?) */
ff3187f6 1885 value = GET_32BIT(pkt->body + pkt->savedpos);
1886 pkt->savedpos += 4;
7cca0d81 1887 return value;
1888}
ff3187f6 1889static int ssh2_pkt_getbool(struct Packet *pkt)
32874aea 1890{
65a22376 1891 unsigned long value;
ff3187f6 1892 if (pkt->length - pkt->savedpos < 1)
32874aea 1893 return 0; /* arrgh, no way to decline (FIXME?) */
ff3187f6 1894 value = pkt->body[pkt->savedpos] != 0;
1895 pkt->savedpos++;
65a22376 1896 return value;
1897}
ff3187f6 1898static void ssh_pkt_getstring(struct Packet *pkt, char **p, int *length)
32874aea 1899{
57356d63 1900 int len;
7cca0d81 1901 *p = NULL;
45068b27 1902 *length = 0;
ff3187f6 1903 if (pkt->length - pkt->savedpos < 4)
32874aea 1904 return;
ff3187f6 1905 len = GET_32BIT(pkt->body + pkt->savedpos);
57356d63 1906 if (len < 0)
1907 return;
1908 *length = len;
ff3187f6 1909 pkt->savedpos += 4;
1910 if (pkt->length - pkt->savedpos < *length)
32874aea 1911 return;
ff3187f6 1912 *p = (char *)(pkt->body + pkt->savedpos);
1913 pkt->savedpos += *length;
7cca0d81 1914}
ff3187f6 1915static void *ssh_pkt_getdata(struct Packet *pkt, int length)
0016d70b 1916{
ff3187f6 1917 if (pkt->length - pkt->savedpos < length)
0016d70b 1918 return NULL;
ff3187f6 1919 pkt->savedpos += length;
1920 return pkt->body + (pkt->savedpos - length);
0016d70b 1921}
ff3187f6 1922static int ssh1_pkt_getrsakey(struct Packet *pkt, struct RSAKey *key,
0016d70b 1923 unsigned char **keystr)
1924{
1925 int j;
1926
ff3187f6 1927 j = makekey(pkt->body + pkt->savedpos,
1928 pkt->length - pkt->savedpos,
0016d70b 1929 key, keystr, 0);
1930
1931 if (j < 0)
1932 return FALSE;
1933
ff3187f6 1934 pkt->savedpos += j;
1935 assert(pkt->savedpos < pkt->length);
0016d70b 1936
1937 return TRUE;
1938}
ff3187f6 1939static Bignum ssh1_pkt_getmp(struct Packet *pkt)
0016d70b 1940{
1941 int j;
1942 Bignum b;
1943
ff3187f6 1944 j = ssh1_read_bignum(pkt->body + pkt->savedpos,
1945 pkt->length - pkt->savedpos, &b);
0016d70b 1946
1947 if (j < 0)
1948 return NULL;
1949
ff3187f6 1950 pkt->savedpos += j;
0016d70b 1951 return b;
1952}
ff3187f6 1953static Bignum ssh2_pkt_getmp(struct Packet *pkt)
32874aea 1954{
7cca0d81 1955 char *p;
3709bfe9 1956 int length;
7cca0d81 1957 Bignum b;
1958
ff3187f6 1959 ssh_pkt_getstring(pkt, &p, &length);
7cca0d81 1960 if (!p)
32874aea 1961 return NULL;
ff3187f6 1962 if (p[0] & 0x80)
32874aea 1963 return NULL;
d8baa528 1964 b = bignum_from_bytes((unsigned char *)p, length);
7cca0d81 1965 return b;
1966}
1967
7d503c31 1968/*
1dd353b5 1969 * Helper function to add an SSH2 signature blob to a packet.
1970 * Expects to be shown the public key blob as well as the signature
1971 * blob. Normally works just like ssh2_pkt_addstring, but will
1972 * fiddle with the signature packet if necessary for
1973 * BUG_SSH2_RSA_PADDING.
1974 */
ff3187f6 1975static void ssh2_add_sigblob(Ssh ssh, struct Packet *pkt,
1976 void *pkblob_v, int pkblob_len,
1dd353b5 1977 void *sigblob_v, int sigblob_len)
1978{
1979 unsigned char *pkblob = (unsigned char *)pkblob_v;
1980 unsigned char *sigblob = (unsigned char *)sigblob_v;
1981
1982 /* dmemdump(pkblob, pkblob_len); */
1983 /* dmemdump(sigblob, sigblob_len); */
1984
1985 /*
1986 * See if this is in fact an ssh-rsa signature and a buggy
1987 * server; otherwise we can just do this the easy way.
1988 */
51470298 1989 if ((ssh->remote_bugs & BUG_SSH2_RSA_PADDING) &&
1dd353b5 1990 (GET_32BIT(pkblob) == 7 && !memcmp(pkblob+4, "ssh-rsa", 7))) {
1991 int pos, len, siglen;
1992
1993 /*
1994 * Find the byte length of the modulus.
1995 */
1996
1997 pos = 4+7; /* skip over "ssh-rsa" */
1998 pos += 4 + GET_32BIT(pkblob+pos); /* skip over exponent */
1999 len = GET_32BIT(pkblob+pos); /* find length of modulus */
2000 pos += 4; /* find modulus itself */
2001 while (len > 0 && pkblob[pos] == 0)
2002 len--, pos++;
2003 /* debug(("modulus length is %d\n", len)); */
2004
2005 /*
2006 * Now find the signature integer.
2007 */
2008 pos = 4+7; /* skip over "ssh-rsa" */
2009 siglen = GET_32BIT(sigblob+pos);
2010 /* debug(("signature length is %d\n", siglen)); */
2011
2012 if (len != siglen) {
2013 unsigned char newlen[4];
ff3187f6 2014 ssh2_pkt_addstring_start(pkt);
2015 ssh2_pkt_addstring_data(pkt, (char *)sigblob, pos);
1dd353b5 2016 /* dmemdump(sigblob, pos); */
2017 pos += 4; /* point to start of actual sig */
2018 PUT_32BIT(newlen, len);
ff3187f6 2019 ssh2_pkt_addstring_data(pkt, (char *)newlen, 4);
1dd353b5 2020 /* dmemdump(newlen, 4); */
2021 newlen[0] = 0;
2022 while (len-- > siglen) {
ff3187f6 2023 ssh2_pkt_addstring_data(pkt, (char *)newlen, 1);
1dd353b5 2024 /* dmemdump(newlen, 1); */
2025 }
ff3187f6 2026 ssh2_pkt_addstring_data(pkt, (char *)(sigblob+pos), siglen);
1dd353b5 2027 /* dmemdump(sigblob+pos, siglen); */
2028 return;
2029 }
2030
2031 /* Otherwise fall through and do it the easy way. */
2032 }
2033
ff3187f6 2034 ssh2_pkt_addstring_start(pkt);
2035 ssh2_pkt_addstring_data(pkt, (char *)sigblob, sigblob_len);
1dd353b5 2036}
2037
2038/*
7d503c31 2039 * Examine the remote side's version string and compare it against
2040 * a list of known buggy implementations.
2041 */
51470298 2042static void ssh_detect_bugs(Ssh ssh, char *vstring)
32874aea 2043{
2044 char *imp; /* pointer to implementation part */
7d503c31 2045 imp = vstring;
2046 imp += strcspn(imp, "-");
bd358db1 2047 if (*imp) imp++;
7d503c31 2048 imp += strcspn(imp, "-");
bd358db1 2049 if (*imp) imp++;
7d503c31 2050
51470298 2051 ssh->remote_bugs = 0;
7d503c31 2052
5ecd7ad0 2053 if (ssh->cfg.sshbug_ignore1 == FORCE_ON ||
2054 (ssh->cfg.sshbug_ignore1 == AUTO &&
2c9c6388 2055 (!strcmp(imp, "1.2.18") || !strcmp(imp, "1.2.19") ||
2056 !strcmp(imp, "1.2.20") || !strcmp(imp, "1.2.21") ||
46ac09aa 2057 !strcmp(imp, "1.2.22") || !strcmp(imp, "Cisco-1.25") ||
bd0b4caf 2058 !strcmp(imp, "OSU_1.4alpha3") || !strcmp(imp, "OSU_1.5alpha4")))) {
32874aea 2059 /*
2060 * These versions don't support SSH1_MSG_IGNORE, so we have
2061 * to use a different defence against password length
2062 * sniffing.
2063 */
51470298 2064 ssh->remote_bugs |= BUG_CHOKES_ON_SSH1_IGNORE;
32874aea 2065 logevent("We believe remote version has SSH1 ignore bug");
7d503c31 2066 }
2067
5ecd7ad0 2068 if (ssh->cfg.sshbug_plainpw1 == FORCE_ON ||
2069 (ssh->cfg.sshbug_plainpw1 == AUTO &&
46ac09aa 2070 (!strcmp(imp, "Cisco-1.25") || !strcmp(imp, "OSU_1.4alpha3")))) {
bd358db1 2071 /*
2072 * These versions need a plain password sent; they can't
2073 * handle having a null and a random length of data after
2074 * the password.
2075 */
51470298 2076 ssh->remote_bugs |= BUG_NEEDS_SSH1_PLAIN_PASSWORD;
bd358db1 2077 logevent("We believe remote version needs a plain SSH1 password");
2078 }
2079
5ecd7ad0 2080 if (ssh->cfg.sshbug_rsa1 == FORCE_ON ||
2081 (ssh->cfg.sshbug_rsa1 == AUTO &&
2c9c6388 2082 (!strcmp(imp, "Cisco-1.25")))) {
0df73905 2083 /*
2084 * These versions apparently have no clue whatever about
2085 * RSA authentication and will panic and die if they see
2086 * an AUTH_RSA message.
2087 */
51470298 2088 ssh->remote_bugs |= BUG_CHOKES_ON_RSA;
0df73905 2089 logevent("We believe remote version can't handle RSA authentication");
2090 }
2091
5ecd7ad0 2092 if (ssh->cfg.sshbug_hmac2 == FORCE_ON ||
2093 (ssh->cfg.sshbug_hmac2 == AUTO &&
b9f387af 2094 !wc_match("* VShell", imp) &&
831301f6 2095 (wc_match("2.1.0*", imp) || wc_match("2.0.*", imp) ||
2096 wc_match("2.2.0*", imp) || wc_match("2.3.0*", imp) ||
2097 wc_match("2.1 *", imp)))) {
32874aea 2098 /*
2099 * These versions have the HMAC bug.
2100 */
51470298 2101 ssh->remote_bugs |= BUG_SSH2_HMAC;
32874aea 2102 logevent("We believe remote version has SSH2 HMAC bug");
7d503c31 2103 }
1dd353b5 2104
5ecd7ad0 2105 if (ssh->cfg.sshbug_derivekey2 == FORCE_ON ||
2106 (ssh->cfg.sshbug_derivekey2 == AUTO &&
b9f387af 2107 !wc_match("* VShell", imp) &&
2856a1b9 2108 (wc_match("2.0.0*", imp) || wc_match("2.0.10*", imp) ))) {
088bde77 2109 /*
2110 * These versions have the key-derivation bug (failing to
2111 * include the literal shared secret in the hashes that
2112 * generate the keys).
2113 */
51470298 2114 ssh->remote_bugs |= BUG_SSH2_DERIVEKEY;
088bde77 2115 logevent("We believe remote version has SSH2 key-derivation bug");
2116 }
2117
5ecd7ad0 2118 if (ssh->cfg.sshbug_rsapad2 == FORCE_ON ||
2119 (ssh->cfg.sshbug_rsapad2 == AUTO &&
831301f6 2120 (wc_match("OpenSSH_2.[5-9]*", imp) ||
2121 wc_match("OpenSSH_3.[0-2]*", imp)))) {
1dd353b5 2122 /*
2123 * These versions have the SSH2 RSA padding bug.
2124 */
51470298 2125 ssh->remote_bugs |= BUG_SSH2_RSA_PADDING;
1dd353b5 2126 logevent("We believe remote version has SSH2 RSA padding bug");
2127 }
8e975795 2128
dda87a28 2129 if (ssh->cfg.sshbug_pksessid2 == FORCE_ON ||
2130 (ssh->cfg.sshbug_pksessid2 == AUTO &&
2131 wc_match("OpenSSH_2.[0-2]*", imp))) {
2132 /*
2133 * These versions have the SSH2 session-ID bug in
2134 * public-key authentication.
2135 */
2136 ssh->remote_bugs |= BUG_SSH2_PK_SESSIONID;
2137 logevent("We believe remote version has SSH2 public-key-session-ID bug");
2138 }
f382c87d 2139
2140 if (ssh->cfg.sshbug_rekey2 == FORCE_ON ||
2141 (ssh->cfg.sshbug_rekey2 == AUTO &&
7cb41bb2 2142 (wc_match("Sun_SSH_1.0", imp) ||
2143 wc_match("Sun_SSH_1.0.1", imp)))) {
f382c87d 2144 /*
2145 * These versions have the SSH2 ignore-rekey bug.
2146 */
2147 ssh->remote_bugs |= BUG_SSH2_REKEY;
2148 logevent("We believe remote version has SSH2 ignore-rekey bug");
2149 }
7d503c31 2150}
2151
d38d6a1f 2152/*
2153 * The `software version' part of an SSH version string is required
2154 * to contain no spaces or minus signs.
2155 */
2156static void ssh_fix_verstring(char *str)
2157{
2158 /* Eat "SSH-<protoversion>-". */
2159 assert(*str == 'S'); str++;
2160 assert(*str == 'S'); str++;
2161 assert(*str == 'H'); str++;
2162 assert(*str == '-'); str++;
2163 while (*str && *str != '-') str++;
2164 assert(*str == '-'); str++;
2165
2166 /* Convert minus signs and spaces in the remaining string into
2167 * underscores. */
2168 while (*str) {
2169 if (*str == '-' || *str == ' ')
2170 *str = '_';
2171 str++;
2172 }
2173}
2174
51470298 2175static int do_ssh_init(Ssh ssh, unsigned char c)
32874aea 2176{
51470298 2177 struct do_ssh_init_state {
2178 int vslen;
2179 char version[10];
2180 char *vstring;
2181 int vstrsize;
2182 int i;
2183 int proto1, proto2;
2184 };
2185 crState(do_ssh_init_state);
374330e2 2186
51470298 2187 crBegin(ssh->do_ssh_init_crstate);
8df7a775 2188
2189 /* Search for the string "SSH-" in the input. */
51470298 2190 s->i = 0;
8df7a775 2191 while (1) {
2192 static const int transS[] = { 1, 2, 2, 1 };
2193 static const int transH[] = { 0, 0, 3, 0 };
2194 static const int transminus[] = { 0, 0, 0, -1 };
32874aea 2195 if (c == 'S')
51470298 2196 s->i = transS[s->i];
32874aea 2197 else if (c == 'H')
51470298 2198 s->i = transH[s->i];
32874aea 2199 else if (c == '-')
51470298 2200 s->i = transminus[s->i];
32874aea 2201 else
51470298 2202 s->i = 0;
2203 if (s->i < 0)
8df7a775 2204 break;
2205 crReturn(1); /* get another character */
374330e2 2206 }
8df7a775 2207
51470298 2208 s->vstrsize = 16;
3d88e64d 2209 s->vstring = snewn(s->vstrsize, char);
51470298 2210 strcpy(s->vstring, "SSH-");
2211 s->vslen = 4;
2212 s->i = 0;
374330e2 2213 while (1) {
8df7a775 2214 crReturn(1); /* get another char */
51470298 2215 if (s->vslen >= s->vstrsize - 1) {
2216 s->vstrsize += 16;
3d88e64d 2217 s->vstring = sresize(s->vstring, s->vstrsize, char);
32874aea 2218 }
51470298 2219 s->vstring[s->vslen++] = c;
2220 if (s->i >= 0) {
374330e2 2221 if (c == '-') {
51470298 2222 s->version[s->i] = '\0';
2223 s->i = -1;
2224 } else if (s->i < sizeof(s->version) - 1)
2225 s->version[s->i++] = c;
c4ffc4d0 2226 } else if (c == '\012')
374330e2 2227 break;
2228 }
2229
51470298 2230 ssh->agentfwd_enabled = FALSE;
2231 ssh->rdpkt2_state.incoming_sequence = 0;
960e736a 2232
51470298 2233 s->vstring[s->vslen] = 0;
a7d4653a 2234 s->vstring[strcspn(s->vstring, "\015\012")] = '\0';/* remove EOL chars */
51470298 2235 {
2236 char *vlog;
3d88e64d 2237 vlog = snewn(20 + s->vslen, char);
51470298 2238 sprintf(vlog, "Server version: %s", s->vstring);
2239 logevent(vlog);
2240 sfree(vlog);
2241 }
2242 ssh_detect_bugs(ssh, s->vstring);
c5e9c988 2243
adf799dd 2244 /*
38d228a2 2245 * Decide which SSH protocol version to support.
adf799dd 2246 */
38d228a2 2247
2248 /* Anything strictly below "2.0" means protocol 1 is supported. */
51470298 2249 s->proto1 = ssh_versioncmp(s->version, "2.0") < 0;
38d228a2 2250 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
51470298 2251 s->proto2 = ssh_versioncmp(s->version, "1.99") >= 0;
38d228a2 2252
86916870 2253 if (ssh->cfg.sshprot == 0 && !s->proto1) {
6b5cf8b4 2254 bombout(("SSH protocol version 1 required by user but not provided by server"));
7ffdbc1a 2255 crStop(0);
38d228a2 2256 }
86916870 2257 if (ssh->cfg.sshprot == 3 && !s->proto2) {
6b5cf8b4 2258 bombout(("SSH protocol version 2 required by user but not provided by server"));
7ffdbc1a 2259 crStop(0);
38d228a2 2260 }
2261
d38d6a1f 2262 {
2263 char *verstring;
2264
2265 if (s->proto2 && (ssh->cfg.sshprot >= 2 || !s->proto1)) {
2266 /*
2267 * Construct a v2 version string.
2268 */
a7d4653a 2269 verstring = dupprintf("SSH-2.0-%s\015\012", sshver);
d38d6a1f 2270 ssh->version = 2;
2271 } else {
2272 /*
2273 * Construct a v1 version string.
2274 */
a7d4653a 2275 verstring = dupprintf("SSH-%s-%s\012",
d38d6a1f 2276 (ssh_versioncmp(s->version, "1.5") <= 0 ?
2277 s->version : "1.5"),
2278 sshver);
2279 ssh->version = 1;
2280 }
2281
2282 ssh_fix_verstring(verstring);
2283
2284 if (ssh->version == 2) {
2285 /*
2286 * Hash our version string and their version string.
2287 */
2288 SHA_Init(&ssh->exhashbase);
0b351b6b 2289 sha_string(&ssh->exhashbase, verstring,
a7d4653a 2290 strcspn(verstring, "\015\012"));
0b351b6b 2291 sha_string(&ssh->exhashbase, s->vstring,
a7d4653a 2292 strcspn(s->vstring, "\015\012"));
d38d6a1f 2293
2294 /*
2295 * Initialise SSHv2 protocol.
2296 */
2297 ssh->protocol = ssh2_protocol;
2298 ssh2_protocol_setup(ssh);
2299 ssh->s_rdpkt = ssh2_rdpkt;
2300 } else {
2301 /*
2302 * Initialise SSHv1 protocol.
2303 */
2304 ssh->protocol = ssh1_protocol;
2305 ssh1_protocol_setup(ssh);
2306 ssh->s_rdpkt = ssh1_rdpkt;
2307 }
2308 logeventf(ssh, "We claim version: %.*s",
a7d4653a 2309 strcspn(verstring, "\015\012"), verstring);
51470298 2310 sk_write(ssh->s, verstring, strlen(verstring));
d38d6a1f 2311 sfree(verstring);
e5574168 2312 }
d38d6a1f 2313
2314 logeventf(ssh, "Using SSH protocol version %d", ssh->version);
2315
125105d1 2316 update_specials_menu(ssh->frontend);
51470298 2317 ssh->state = SSH_STATE_BEFORE_SIZE;
39934deb 2318 ssh->pinger = pinger_new(&ssh->cfg, &ssh_backend, ssh);
8df7a775 2319
51470298 2320 sfree(s->vstring);
50526e47 2321
8df7a775 2322 crFinish(0);
2323}
2324
51470298 2325static void ssh_gotdata(Ssh ssh, unsigned char *data, int datalen)
8df7a775 2326{
51470298 2327 crBegin(ssh->ssh_gotdata_crstate);
8df7a775 2328
2329 /*
2330 * To begin with, feed the characters one by one to the
2331 * protocol initialisation / selection function do_ssh_init().
2332 * When that returns 0, we're done with the initial greeting
2333 * exchange and can move on to packet discipline.
2334 */
2335 while (1) {
51470298 2336 int ret; /* need not be kept across crReturn */
8df7a775 2337 if (datalen == 0)
2338 crReturnV; /* more data please */
51470298 2339 ret = do_ssh_init(ssh, *data);
32874aea 2340 data++;
2341 datalen--;
8df7a775 2342 if (ret == 0)
2343 break;
2344 }
2345
2346 /*
2347 * We emerge from that loop when the initial negotiation is
2348 * over and we have selected an s_rdpkt function. Now pass
2349 * everything to s_rdpkt, and then pass the resulting packets
2350 * to the proper protocol handler.
2351 */
2352 if (datalen == 0)
2353 crReturnV;
2354 while (1) {
2355 while (datalen > 0) {
ff3187f6 2356 struct Packet *pktin = ssh->s_rdpkt(ssh, &data, &datalen);
2357 if (pktin) {
2358 ssh->protocol(ssh, NULL, 0, pktin);
2359 ssh_free_packet(pktin);
8df7a775 2360 }
ff3187f6 2361 if (ssh->state == SSH_STATE_CLOSED)
2362 return;
8df7a775 2363 }
2364 crReturnV;
2365 }
2366 crFinishV;
2367}
2368
36f94d1f 2369static void ssh_do_close(Ssh ssh)
32874aea 2370{
36f94d1f 2371 int i;
2372 struct ssh_channel *c;
2373
51470298 2374 ssh->state = SSH_STATE_CLOSED;
2375 if (ssh->s) {
2376 sk_close(ssh->s);
2377 ssh->s = NULL;
39934deb 2378 notify_remote_exit(ssh->frontend);
f3ab576e 2379 }
36f94d1f 2380 /*
2381 * Now we must shut down any port and X forwardings going
2382 * through this connection.
2383 */
74a98066 2384 if (ssh->channels) {
2385 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
2386 switch (c->type) {
2387 case CHAN_X11:
2388 x11_close(c->u.x11.s);
2389 break;
2390 case CHAN_SOCKDATA:
2391 pfd_close(c->u.pfd.s);
2392 break;
2393 }
2394 del234(ssh->channels, c);
2395 if (ssh->version == 2)
2396 bufchain_clear(&c->v.v2.outbuffer);
2397 sfree(c);
36f94d1f 2398 }
36f94d1f 2399 }
2400}
2401
cbe2d68f 2402static int ssh_closing(Plug plug, const char *error_msg, int error_code,
36f94d1f 2403 int calling_back)
2404{
2405 Ssh ssh = (Ssh) plug;
2406 ssh_do_close(ssh);
7e78000d 2407 if (error_msg) {
32874aea 2408 /* A socket error has occurred. */
247308b5 2409 logevent(error_msg);
971bcc0a 2410 connection_fatal(ssh->frontend, "%s", error_msg);
7e78000d 2411 } else {
2412 /* Otherwise, the remote side closed the connection normally. */
8df7a775 2413 }
7e78000d 2414 return 0;
2415}
2416
32874aea 2417static int ssh_receive(Plug plug, int urgent, char *data, int len)
2418{
51470298 2419 Ssh ssh = (Ssh) plug;
d8baa528 2420 ssh_gotdata(ssh, (unsigned char *)data, len);
51470298 2421 if (ssh->state == SSH_STATE_CLOSED) {
36f94d1f 2422 ssh_do_close(ssh);
32874aea 2423 return 0;
3257deae 2424 }
fef97f43 2425 return 1;
374330e2 2426}
2427
5471d09a 2428static void ssh_sent(Plug plug, int bufsize)
2429{
51470298 2430 Ssh ssh = (Ssh) plug;
5471d09a 2431 /*
2432 * If the send backlog on the SSH socket itself clears, we
2433 * should unthrottle the whole world if it was throttled.
2434 */
2435 if (bufsize < SSH_MAX_BACKLOG)
51470298 2436 ssh_throttle_all(ssh, 0, bufsize);
5471d09a 2437}
2438
fb09bf1c 2439/*
8df7a775 2440 * Connect to specified host and port.
2441 * Returns an error message, or NULL on success.
6e1ebb76 2442 * Also places the canonical host name into `realhost'. It must be
2443 * freed by the caller.
8df7a775 2444 */
cbe2d68f 2445static const char *connect_to_host(Ssh ssh, char *host, int port,
79bf227b 2446 char **realhost, int nodelay, int keepalive)
8df7a775 2447{
51470298 2448 static const struct plug_function_table fn_table = {
7e78000d 2449 ssh_closing,
5471d09a 2450 ssh_receive,
2451 ssh_sent,
2452 NULL
51470298 2453 };
7e78000d 2454
8df7a775 2455 SockAddr addr;
cbe2d68f 2456 const char *err;
8df7a775 2457
3d88e64d 2458 ssh->savedhost = snewn(1 + strlen(host), char);
51470298 2459 if (!ssh->savedhost)
8df7a775 2460 fatalbox("Out of memory");
51470298 2461 strcpy(ssh->savedhost, host);
8df7a775 2462
2463 if (port < 0)
2464 port = 22; /* default ssh port */
51470298 2465 ssh->savedport = port;
8df7a775 2466
2467 /*
2468 * Try to find host.
2469 */
05581745 2470 logeventf(ssh, "Looking up host \"%s\"%s", host,
2471 (ssh->cfg.addressfamily == ADDRTYPE_IPV4 ? " (IPv4)" :
2472 (ssh->cfg.addressfamily == ADDRTYPE_IPV6 ? " (IPv6)" : "")));
2473 addr = name_lookup(host, port, realhost, &ssh->cfg,
2474 ssh->cfg.addressfamily);
170c1e6e 2475 if ((err = sk_addr_error(addr)) != NULL) {
2476 sk_addr_free(addr);
8df7a775 2477 return err;
170c1e6e 2478 }
8df7a775 2479
8df7a775 2480 /*
2481 * Open socket.
2482 */
3ad9d396 2483 {
57356d63 2484 char addrbuf[100];
3ad9d396 2485 sk_getaddr(addr, addrbuf, 100);
57356d63 2486 logeventf(ssh, "Connecting to %s port %d", addrbuf, port);
3ad9d396 2487 }
51470298 2488 ssh->fn = &fn_table;
e8fa8f62 2489 ssh->s = new_connection(addr, *realhost, port,
79bf227b 2490 0, 1, nodelay, keepalive, (Plug) ssh, &ssh->cfg);
70e5d0fd 2491 if ((err = sk_socket_error(ssh->s)) != NULL) {
51470298 2492 ssh->s = NULL;
39934deb 2493 notify_remote_exit(ssh->frontend);
8df7a775 2494 return err;
67c4ba2e 2495 }
8df7a775 2496
8df7a775 2497 return NULL;
2498}
2499
2500/*
5471d09a 2501 * Throttle or unthrottle the SSH connection.
2502 */
51470298 2503static void ssh1_throttle(Ssh ssh, int adjust)
5471d09a 2504{
51470298 2505 int old_count = ssh->v1_throttle_count;
2506 ssh->v1_throttle_count += adjust;
2507 assert(ssh->v1_throttle_count >= 0);
2508 if (ssh->v1_throttle_count && !old_count) {
2509 sk_set_frozen(ssh->s, 1);
2510 } else if (!ssh->v1_throttle_count && old_count) {
2511 sk_set_frozen(ssh->s, 0);
5471d09a 2512 }
2513}
2514
2515/*
2516 * Throttle or unthrottle _all_ local data streams (for when sends
2517 * on the SSH connection itself back up).
2518 */
51470298 2519static void ssh_throttle_all(Ssh ssh, int enable, int bufsize)
5471d09a 2520{
2521 int i;
2522 struct ssh_channel *c;
2523
51470298 2524 if (enable == ssh->throttled_all)
5471d09a 2525 return;
51470298 2526 ssh->throttled_all = enable;
2527 ssh->overall_bufsize = bufsize;
2528 if (!ssh->channels)
5471d09a 2529 return;
51470298 2530 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
5471d09a 2531 switch (c->type) {
2532 case CHAN_MAINSESSION:
2533 /*
2534 * This is treated separately, outside the switch.
2535 */
2536 break;
2537 case CHAN_X11:
2538 x11_override_throttle(c->u.x11.s, enable);
2539 break;
2540 case CHAN_AGENT:
2541 /* Agent channels require no buffer management. */
2542 break;
2543 case CHAN_SOCKDATA:
36f94d1f 2544 pfd_override_throttle(c->u.pfd.s, enable);
5471d09a 2545 break;
2546 }
2547 }
2548}
2549
2550/*
51470298 2551 * Username and password input, abstracted off into routines
2552 * reusable in several places - even between SSH1 and SSH2.
0405e71f 2553 */
0405e71f 2554
2555/* Set up a username or password input loop on a given buffer. */
ae9ae89f 2556static void setup_userpass_input(Ssh ssh, char *buffer, int buflen, int echo)
0405e71f 2557{
51470298 2558 ssh->userpass_input_buffer = buffer;
2559 ssh->userpass_input_buflen = buflen;
2560 ssh->userpass_input_bufpos = 0;
2561 ssh->userpass_input_echo = echo;
0405e71f 2562}
2563
2564/*
2565 * Process some terminal data in the course of username/password
2566 * input. Returns >0 for success (line of input returned in
2567 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2568 * for inconclusive (keep waiting for more input please).
2569 */
ae9ae89f 2570static int process_userpass_input(Ssh ssh, unsigned char *in, int inlen)
0405e71f 2571{
2572 char c;
2573
2574 while (inlen--) {
2575 switch (c = *in++) {
2576 case 10:
2577 case 13:
51470298 2578 ssh->userpass_input_buffer[ssh->userpass_input_bufpos] = 0;
2579 ssh->userpass_input_buffer[ssh->userpass_input_buflen-1] = 0;
0405e71f 2580 return +1;
2581 break;
2582 case 8:
2583 case 127:
51470298 2584 if (ssh->userpass_input_bufpos > 0) {
2585 if (ssh->userpass_input_echo)
2586 c_write_str(ssh, "\b \b");
2587 ssh->userpass_input_bufpos--;
0405e71f 2588 }
2589 break;
2590 case 21:
2591 case 27:
51470298 2592 while (ssh->userpass_input_bufpos > 0) {
2593 if (ssh->userpass_input_echo)
2594 c_write_str(ssh, "\b \b");
2595 ssh->userpass_input_bufpos--;
0405e71f 2596 }
2597 break;
2598 case 3:
2599 case 4:
2600 return -1;
2601 break;
2602 default:
4692a14a 2603 /*
2604 * This simplistic check for printability is disabled
2605 * when we're doing password input, because some people
2606 * have control characters in their passwords.o
2607 */
2608 if ((!ssh->userpass_input_echo ||
2609 (c >= ' ' && c <= '~') ||
0405e71f 2610 ((unsigned char) c >= 160))
51470298 2611 && ssh->userpass_input_bufpos < ssh->userpass_input_buflen-1) {
2612 ssh->userpass_input_buffer[ssh->userpass_input_bufpos++] = c;
2613 if (ssh->userpass_input_echo)
2614 c_write(ssh, &c, 1);
0405e71f 2615 }
2616 break;
2617 }
2618 }
2619 return 0;
2620}
2621
f11d78f2 2622static void ssh_agent_callback(void *sshv, void *reply, int replylen)
839f10db 2623{
2624 Ssh ssh = (Ssh) sshv;
2625
2626 ssh->agent_response = reply;
2627 ssh->agent_response_len = replylen;
2628
2629 if (ssh->version == 1)
ff3187f6 2630 do_ssh1_login(ssh, NULL, -1, NULL);
839f10db 2631 else
ff3187f6 2632 do_ssh2_authconn(ssh, NULL, -1, NULL);
839f10db 2633}
2634
f11d78f2 2635static void ssh_agentf_callback(void *cv, void *reply, int replylen)
839f10db 2636{
2637 struct ssh_channel *c = (struct ssh_channel *)cv;
2638 Ssh ssh = c->ssh;
2639 void *sentreply = reply;
2640
2641 if (!sentreply) {
2642 /* Fake SSH_AGENT_FAILURE. */
2643 sentreply = "\0\0\0\1\5";
2644 replylen = 5;
2645 }
2646 if (ssh->version == 2) {
2647 ssh2_add_channel_data(c, sentreply, replylen);
2648 ssh2_try_send(c);
2649 } else {
2650 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
2651 PKT_INT, c->remoteid,
9a10ecf4 2652 PKTT_DATA,
839f10db 2653 PKT_INT, replylen,
2654 PKT_DATA, sentreply, replylen,
9a10ecf4 2655 PKTT_OTHER,
839f10db 2656 PKT_END);
2657 }
2658 if (reply)
2659 sfree(reply);
2660}
2661
0405e71f 2662/*
fb09bf1c 2663 * Handle the key exchange and user authentication phases.
2664 */
ff3187f6 2665static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen,
2666 struct Packet *pktin)
fb09bf1c 2667{
0016d70b 2668 int i, j, ret;
2669 unsigned char cookie[8], *ptr;
374330e2 2670 struct RSAKey servkey, hostkey;
2671 struct MD5Context md5c;
51470298 2672 struct do_ssh1_login_state {
2673 int len;
2674 unsigned char *rsabuf, *keystr1, *keystr2;
2675 unsigned long supported_ciphers_mask, supported_auths_mask;
2676 int tried_publickey, tried_agent;
2677 int tis_auth_refused, ccard_auth_refused;
2678 unsigned char session_id[16];
2679 int cipher_type;
2680 char username[100];
2681 void *publickey_blob;
2682 int publickey_bloblen;
2683 char password[100];
2684 char prompt[200];
2685 int pos;
2686 char c;
2687 int pwpkt_type;
2688 unsigned char request[5], *response, *p;
2689 int responselen;
2690 int keyi, nkeys;
2691 int authed;
2692 struct RSAKey key;
2693 Bignum challenge;
2694 char *commentp;
2695 int commentlen;
2696 };
2697 crState(do_ssh1_login_state);
2698
2699 crBegin(ssh->do_ssh1_login_crstate);
374330e2 2700
ff3187f6 2701 if (!pktin)
2702 crWaitUntil(pktin);
374330e2 2703
ff3187f6 2704 if (pktin->type != SSH1_SMSG_PUBLIC_KEY) {
6b5cf8b4 2705 bombout(("Public key packet not received"));
7ffdbc1a 2706 crStop(0);
8d5de777 2707 }
374330e2 2708
c5e9c988 2709 logevent("Received public keys");
374330e2 2710
ff3187f6 2711 ptr = ssh_pkt_getdata(pktin, 8);
0016d70b 2712 if (!ptr) {
2713 bombout(("SSH1 public key packet stopped before random cookie"));
2714 crStop(0);
2715 }
2716 memcpy(cookie, ptr, 8);
374330e2 2717
ff3187f6 2718 if (!ssh1_pkt_getrsakey(pktin, &servkey, &s->keystr1) ||
2719 !ssh1_pkt_getrsakey(pktin, &hostkey, &s->keystr2)) {
ae0500e5 2720 bombout(("Failed to read SSH1 public keys from public key packet"));
0016d70b 2721 crStop(0);
2722 }
374330e2 2723
c5e9c988 2724 /*
1c2a93c4 2725 * Log the host key fingerprint.
c5e9c988 2726 */
c5e9c988 2727 {
2728 char logmsg[80];
1c2a93c4 2729 logevent("Host key fingerprint is:");
c5e9c988 2730 strcpy(logmsg, " ");
32874aea 2731 hostkey.comment = NULL;
2732 rsa_fingerprint(logmsg + strlen(logmsg),
2733 sizeof(logmsg) - strlen(logmsg), &hostkey);
c5e9c988 2734 logevent(logmsg);
2735 }
2736
ff3187f6 2737 ssh->v1_remote_protoflags = ssh_pkt_getuint32(pktin);
2738 s->supported_ciphers_mask = ssh_pkt_getuint32(pktin);
2739 s->supported_auths_mask = ssh_pkt_getuint32(pktin);
bea1ef5f 2740
51470298 2741 ssh->v1_local_protoflags =
2742 ssh->v1_remote_protoflags & SSH1_PROTOFLAGS_SUPPORTED;
2743 ssh->v1_local_protoflags |= SSH1_PROTOFLAG_SCREEN_NUMBER;
b96dc54c 2744
c5e9c988 2745 MD5Init(&md5c);
51470298 2746 MD5Update(&md5c, s->keystr2, hostkey.bytes);
2747 MD5Update(&md5c, s->keystr1, servkey.bytes);
0016d70b 2748 MD5Update(&md5c, cookie, 8);
51470298 2749 MD5Final(s->session_id, &md5c);
374330e2 2750
32874aea 2751 for (i = 0; i < 32; i++)
51470298 2752 ssh->session_key[i] = random_byte();
374330e2 2753
0016d70b 2754 /*
2755 * Verify that the `bits' and `bytes' parameters match.
2756 */
2757 if (hostkey.bits > hostkey.bytes * 8 ||
2758 servkey.bits > servkey.bytes * 8) {
2759 bombout(("SSH1 public keys were badly formatted"));
2760 crStop(0);
2761 }
2762
51470298 2763 s->len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
374330e2 2764
3d88e64d 2765 s->rsabuf = snewn(s->len, unsigned char);
51470298 2766 if (!s->rsabuf)
374330e2 2767 fatalbox("Out of memory");
2768
89ee5268 2769 /*
2770 * Verify the host key.
2771 */
2772 {
32874aea 2773 /*
2774 * First format the key into a string.
2775 */
2776 int len = rsastr_len(&hostkey);
2777 char fingerprint[100];
3d88e64d 2778 char *keystr = snewn(len, char);
32874aea 2779 if (!keystr)
2780 fatalbox("Out of memory");
2781 rsastr_fmt(keystr, &hostkey);
2782 rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
a8327734 2783 verify_ssh_host_key(ssh->frontend,
2784 ssh->savedhost, ssh->savedport, "rsa", keystr,
32874aea 2785 fingerprint);
2786 sfree(keystr);
2787 }
2788
2789 for (i = 0; i < 32; i++) {
51470298 2790 s->rsabuf[i] = ssh->session_key[i];
374330e2 2791 if (i < 16)
51470298 2792 s->rsabuf[i] ^= s->session_id[i];
374330e2 2793 }
2794
2795 if (hostkey.bytes > servkey.bytes) {
0016d70b 2796 ret = rsaencrypt(s->rsabuf, 32, &servkey);
2797 if (ret)
2798 ret = rsaencrypt(s->rsabuf, servkey.bytes, &hostkey);
374330e2 2799 } else {
0016d70b 2800 ret = rsaencrypt(s->rsabuf, 32, &hostkey);
2801 if (ret)
2802 ret = rsaencrypt(s->rsabuf, hostkey.bytes, &servkey);
2803 }
2804 if (!ret) {
2805 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2806 crStop(0);
374330e2 2807 }
2808
c5e9c988 2809 logevent("Encrypted session key");
2810
ca20bfcf 2811 {
2812 int cipher_chosen = 0, warn = 0;
2813 char *cipher_string = NULL;
51470298 2814 int i;
ca20bfcf 2815 for (i = 0; !cipher_chosen && i < CIPHER_MAX; i++) {
86916870 2816 int next_cipher = ssh->cfg.ssh_cipherlist[i];
ca20bfcf 2817 if (next_cipher == CIPHER_WARN) {
2818 /* If/when we choose a cipher, warn about it */
2819 warn = 1;
2820 } else if (next_cipher == CIPHER_AES) {
2821 /* XXX Probably don't need to mention this. */
2822 logevent("AES not supported in SSH1, skipping");
2823 } else {
2824 switch (next_cipher) {
51470298 2825 case CIPHER_3DES: s->cipher_type = SSH_CIPHER_3DES;
ca20bfcf 2826 cipher_string = "3DES"; break;
51470298 2827 case CIPHER_BLOWFISH: s->cipher_type = SSH_CIPHER_BLOWFISH;
ca20bfcf 2828 cipher_string = "Blowfish"; break;
51470298 2829 case CIPHER_DES: s->cipher_type = SSH_CIPHER_DES;
ca20bfcf 2830 cipher_string = "single-DES"; break;
2831 }
51470298 2832 if (s->supported_ciphers_mask & (1 << s->cipher_type))
ca20bfcf 2833 cipher_chosen = 1;
2834 }
2835 }
2836 if (!cipher_chosen) {
51470298 2837 if ((s->supported_ciphers_mask & (1 << SSH_CIPHER_3DES)) == 0)
6b5cf8b4 2838 bombout(("Server violates SSH 1 protocol by not "
ca20bfcf 2839 "supporting 3DES encryption"));
2840 else
2841 /* shouldn't happen */
6b5cf8b4 2842 bombout(("No supported ciphers found"));
7ffdbc1a 2843 crStop(0);
a99a05c0 2844 }
ca20bfcf 2845
2846 /* Warn about chosen cipher if necessary. */
bb348ab1 2847 if (warn) {
2848 sk_set_frozen(ssh->s, 1);
83e7d008 2849 askalg(ssh->frontend, "cipher", cipher_string);
bb348ab1 2850 sk_set_frozen(ssh->s, 0);
2851 }
bea1ef5f 2852 }
ca20bfcf 2853
51470298 2854 switch (s->cipher_type) {
32874aea 2855 case SSH_CIPHER_3DES:
2856 logevent("Using 3DES encryption");
2857 break;
2858 case SSH_CIPHER_DES:
2859 logevent("Using single-DES encryption");
2860 break;
2861 case SSH_CIPHER_BLOWFISH:
2862 logevent("Using Blowfish encryption");
2863 break;
c5e9c988 2864 }
bea1ef5f 2865
51470298 2866 send_packet(ssh, SSH1_CMSG_SESSION_KEY,
2867 PKT_CHAR, s->cipher_type,
32874aea 2868 PKT_DATA, cookie, 8,
51470298 2869 PKT_CHAR, (s->len * 8) >> 8, PKT_CHAR, (s->len * 8) & 0xFF,
2870 PKT_DATA, s->rsabuf, s->len,
2871 PKT_INT, ssh->v1_local_protoflags, PKT_END);
fb09bf1c 2872
c5e9c988 2873 logevent("Trying to enable encryption...");
374330e2 2874
51470298 2875 sfree(s->rsabuf);
374330e2 2876
51470298 2877 ssh->cipher = (s->cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
2878 s->cipher_type == SSH_CIPHER_DES ? &ssh_des :
2879 &ssh_3des);
371e569c 2880 ssh->v1_cipher_ctx = ssh->cipher->make_context();
2881 ssh->cipher->sesskey(ssh->v1_cipher_ctx, ssh->session_key);
57356d63 2882 logeventf(ssh, "Initialised %s encryption", ssh->cipher->text_name);
374330e2 2883
0183b242 2884 ssh->crcda_ctx = crcda_make_context();
2885 logevent("Installing CRC compensation attack detector");
2886
679539d7 2887 if (servkey.modulus) {
2888 sfree(servkey.modulus);
2889 servkey.modulus = NULL;
2890 }
2891 if (servkey.exponent) {
2892 sfree(servkey.exponent);
2893 servkey.exponent = NULL;
2894 }
2895 if (hostkey.modulus) {
2896 sfree(hostkey.modulus);
2897 hostkey.modulus = NULL;
2898 }
2899 if (hostkey.exponent) {
2900 sfree(hostkey.exponent);
2901 hostkey.exponent = NULL;
2902 }
ff3187f6 2903 crWaitUntil(pktin);
374330e2 2904
ff3187f6 2905 if (pktin->type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 2906 bombout(("Encryption not successfully enabled"));
7ffdbc1a 2907 crStop(0);
8d5de777 2908 }
374330e2 2909
c5e9c988 2910 logevent("Successfully started encryption");
2911
374330e2 2912 fflush(stdout);
2913 {
aa09f7d0 2914 if (!*ssh->cfg.username) {
c0a81592 2915 if (ssh_get_line && !ssh_getline_pw_only) {
32874aea 2916 if (!ssh_get_line("login as: ",
51470298 2917 s->username, sizeof(s->username), FALSE)) {
32874aea 2918 /*
2919 * get_line failed to get a username.
2920 * Terminate.
2921 */
2922 logevent("No username provided. Abandoning session.");
3bb2f322 2923 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 2924 crStop(1);
32874aea 2925 }
2926 } else {
51470298 2927 int ret; /* need not be kept over crReturn */
2928 c_write_str(ssh, "login as: ");
2929 ssh->send_ok = 1;
0405e71f 2930
51470298 2931 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
0405e71f 2932 do {
ff3187f6 2933 crWaitUntil(!pktin);
51470298 2934 ret = process_userpass_input(ssh, in, inlen);
0405e71f 2935 } while (ret == 0);
2936 if (ret < 0)
2937 cleanup_exit(0);
51470298 2938 c_write_str(ssh, "\r\n");
32874aea 2939 }
2940 } else {
86916870 2941 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
51470298 2942 s->username[sizeof(s->username)-1] = '\0';
374330e2 2943 }
fb09bf1c 2944
51470298 2945 send_packet(ssh, SSH1_CMSG_USER, PKT_STR, s->username, PKT_END);
c5e9c988 2946 {
51470298 2947 char userlog[22 + sizeof(s->username)];
2948 sprintf(userlog, "Sent username \"%s\"", s->username);
c5e9c988 2949 logevent(userlog);
32874aea 2950 if (flags & FLAG_INTERACTIVE &&
2951 (!((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)))) {
3c8e959b 2952 strcat(userlog, "\r\n");
51470298 2953 c_write_str(ssh, userlog);
3c8e959b 2954 }
c5e9c988 2955 }
374330e2 2956 }
2957
ff3187f6 2958 crWaitUntil(pktin);
374330e2 2959
51470298 2960 if ((ssh->remote_bugs & BUG_CHOKES_ON_RSA)) {
0df73905 2961 /* We must not attempt PK auth. Pretend we've already tried it. */
51470298 2962 s->tried_publickey = s->tried_agent = 1;
0df73905 2963 } else {
51470298 2964 s->tried_publickey = s->tried_agent = 0;
0df73905 2965 }
51470298 2966 s->tis_auth_refused = s->ccard_auth_refused = 0;
86916870 2967 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
9a30e26b 2968 if (!filename_is_null(ssh->cfg.keyfile)) {
2969 if (!rsakey_pubblob(&ssh->cfg.keyfile,
222d54dc 2970 &s->publickey_blob, &s->publickey_bloblen, NULL))
51470298 2971 s->publickey_blob = NULL;
396778f1 2972 } else
51470298 2973 s->publickey_blob = NULL;
7cca0d81 2974
ff3187f6 2975 while (pktin->type == SSH1_SMSG_FAILURE) {
51470298 2976 s->pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
614a20a0 2977
51470298 2978 if (agent_exists() && !s->tried_agent) {
32874aea 2979 /*
2980 * Attempt RSA authentication using Pageant.
2981 */
32874aea 2982 void *r;
2983
51470298 2984 s->authed = FALSE;
2985 s->tried_agent = 1;
32874aea 2986 logevent("Pageant is running. Requesting keys.");
2987
2988 /* Request the keys held by the agent. */
51470298 2989 PUT_32BIT(s->request, 1);
2990 s->request[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES;
839f10db 2991 if (!agent_query(s->request, 5, &r, &s->responselen,
2992 ssh_agent_callback, ssh)) {
2993 do {
2994 crReturn(0);
ff3187f6 2995 if (pktin) {
839f10db 2996 bombout(("Unexpected data from server while waiting"
2997 " for agent response"));
2998 crStop(0);
2999 }
ff3187f6 3000 } while (pktin || inlen > 0);
839f10db 3001 r = ssh->agent_response;
3002 s->responselen = ssh->agent_response_len;
3003 }
51470298 3004 s->response = (unsigned char *) r;
3005 if (s->response && s->responselen >= 5 &&
3006 s->response[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER) {
3007 s->p = s->response + 5;
3008 s->nkeys = GET_32BIT(s->p);
3009 s->p += 4;
32874aea 3010 {
3011 char buf[64];
51470298 3012 sprintf(buf, "Pageant has %d SSH1 keys", s->nkeys);
32874aea 3013 logevent(buf);
3014 }
51470298 3015 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
32874aea 3016 {
3017 char buf[64];
51470298 3018 sprintf(buf, "Trying Pageant key #%d", s->keyi);
32874aea 3019 logevent(buf);
3020 }
51470298 3021 if (s->publickey_blob &&
3022 !memcmp(s->p, s->publickey_blob,
3023 s->publickey_bloblen)) {
396778f1 3024 logevent("This key matches configured key file");
51470298 3025 s->tried_publickey = 1;
396778f1 3026 }
51470298 3027 s->p += 4;
0016d70b 3028 {
3029 int n, ok = FALSE;
3030 do { /* do while (0) to make breaking easy */
3031 n = ssh1_read_bignum
3032 (s->p, s->responselen-(s->p-s->response),
3033 &s->key.exponent);
3034 if (n < 0)
3035 break;
3036 s->p += n;
3037 n = ssh1_read_bignum
3038 (s->p, s->responselen-(s->p-s->response),
3039 &s->key.modulus);
3040 if (n < 0)
3041 break;
3042 s->p += n;
3043 if (s->responselen - (s->p-s->response) < 4)
3044 break;
3045 s->commentlen = GET_32BIT(s->p);
3046 s->p += 4;
3047 if (s->responselen - (s->p-s->response) <
3048 s->commentlen)
3049 break;
3050 s->commentp = (char *)s->p;
3051 s->p += s->commentlen;
3052 ok = TRUE;
3053 } while (0);
3054 if (!ok) {
3055 logevent("Pageant key list packet was truncated");
3056 break;
3057 }
3058 }
51470298 3059 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
3060 PKT_BIGNUM, s->key.modulus, PKT_END);
ff3187f6 3061 crWaitUntil(pktin);
3062 if (pktin->type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
32874aea 3063 logevent("Key refused");
3064 continue;
3065 }
3066 logevent("Received RSA challenge");
ff3187f6 3067 if ((s->challenge = ssh1_pkt_getmp(pktin)) == NULL) {
0016d70b 3068 bombout(("Server's RSA challenge was badly formatted"));
3069 crStop(0);
3070 }
3071
32874aea 3072 {
3073 char *agentreq, *q, *ret;
2d466ffd 3074 void *vret;
32874aea 3075 int len, retlen;
3076 len = 1 + 4; /* message type, bit count */
51470298 3077 len += ssh1_bignum_length(s->key.exponent);
3078 len += ssh1_bignum_length(s->key.modulus);
3079 len += ssh1_bignum_length(s->challenge);
32874aea 3080 len += 16; /* session id */
3081 len += 4; /* response format */
3d88e64d 3082 agentreq = snewn(4 + len, char);
32874aea 3083 PUT_32BIT(agentreq, len);
3084 q = agentreq + 4;
3085 *q++ = SSH1_AGENTC_RSA_CHALLENGE;
51470298 3086 PUT_32BIT(q, bignum_bitcount(s->key.modulus));
32874aea 3087 q += 4;
51470298 3088 q += ssh1_write_bignum(q, s->key.exponent);
3089 q += ssh1_write_bignum(q, s->key.modulus);
3090 q += ssh1_write_bignum(q, s->challenge);
3091 memcpy(q, s->session_id, 16);
32874aea 3092 q += 16;
3093 PUT_32BIT(q, 1); /* response format */
839f10db 3094 if (!agent_query(agentreq, len + 4, &vret, &retlen,
3095 ssh_agent_callback, ssh)) {
3096 sfree(agentreq);
3097 do {
3098 crReturn(0);
ff3187f6 3099 if (pktin) {
839f10db 3100 bombout(("Unexpected data from server"
3101 " while waiting for agent"
3102 " response"));
3103 crStop(0);
3104 }
ff3187f6 3105 } while (pktin || inlen > 0);
839f10db 3106 vret = ssh->agent_response;
3107 retlen = ssh->agent_response_len;
3108 } else
3109 sfree(agentreq);
2d466ffd 3110 ret = vret;
32874aea 3111 if (ret) {
3112 if (ret[4] == SSH1_AGENT_RSA_RESPONSE) {
3113 logevent("Sending Pageant's response");
51470298 3114 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
32874aea 3115 PKT_DATA, ret + 5, 16,
3116 PKT_END);
3117 sfree(ret);
ff3187f6 3118 crWaitUntil(pktin);
3119 if (pktin->type == SSH1_SMSG_SUCCESS) {
32874aea 3120 logevent
3121 ("Pageant's response accepted");
3122 if (flags & FLAG_VERBOSE) {
51470298 3123 c_write_str(ssh, "Authenticated using"
3124 " RSA key \"");
3125 c_write(ssh, s->commentp,
3126 s->commentlen);
3127 c_write_str(ssh, "\" from agent\r\n");
32874aea 3128 }
51470298 3129 s->authed = TRUE;
32874aea 3130 } else
3131 logevent
3132 ("Pageant's response not accepted");
3133 } else {
3134 logevent
3135 ("Pageant failed to answer challenge");
3136 sfree(ret);
3137 }
3138 } else {
3139 logevent("No reply received from Pageant");
3140 }
3141 }
51470298 3142 freebn(s->key.exponent);
3143 freebn(s->key.modulus);
3144 freebn(s->challenge);
3145 if (s->authed)
32874aea 3146 break;
3147 }
29b1d0b3 3148 sfree(s->response);
32874aea 3149 }
51470298 3150 if (s->authed)
32874aea 3151 break;
3152 }
9a30e26b 3153 if (!filename_is_null(ssh->cfg.keyfile) && !s->tried_publickey)
51470298 3154 s->pwpkt_type = SSH1_CMSG_AUTH_RSA;
32874aea 3155
86916870 3156 if (ssh->cfg.try_tis_auth &&
51470298 3157 (s->supported_auths_mask & (1 << SSH1_AUTH_TIS)) &&
3158 !s->tis_auth_refused) {
3159 s->pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
32874aea 3160 logevent("Requested TIS authentication");
51470298 3161 send_packet(ssh, SSH1_CMSG_AUTH_TIS, PKT_END);
ff3187f6 3162 crWaitUntil(pktin);
3163 if (pktin->type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
32874aea 3164 logevent("TIS authentication declined");
3165 if (flags & FLAG_INTERACTIVE)
51470298 3166 c_write_str(ssh, "TIS authentication refused.\r\n");
3167 s->tis_auth_refused = 1;
614a20a0 3168 continue;
32874aea 3169 } else {
0016d70b 3170 char *challenge;
3171 int challengelen;
3172
ff3187f6 3173 ssh_pkt_getstring(pktin, &challenge, &challengelen);
0016d70b 3174 if (!challenge) {
3175 bombout(("TIS challenge packet was badly formed"));
3176 crStop(0);
3177 }
32874aea 3178 logevent("Received TIS challenge");
51470298 3179 if (challengelen > sizeof(s->prompt) - 1)
3180 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
0016d70b 3181 memcpy(s->prompt, challenge, challengelen);
614a20a0 3182 /* Prompt heuristic comes from OpenSSH */
51470298 3183 strncpy(s->prompt + challengelen,
3184 memchr(s->prompt, '\n', challengelen) ?
614a20a0 3185 "": "\r\nResponse: ",
51470298 3186 (sizeof s->prompt) - challengelen);
3187 s->prompt[(sizeof s->prompt) - 1] = '\0';
32874aea 3188 }
3189 }
86916870 3190 if (ssh->cfg.try_tis_auth &&
51470298 3191 (s->supported_auths_mask & (1 << SSH1_AUTH_CCARD)) &&
3192 !s->ccard_auth_refused) {
3193 s->pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
32874aea 3194 logevent("Requested CryptoCard authentication");
51470298 3195 send_packet(ssh, SSH1_CMSG_AUTH_CCARD, PKT_END);
ff3187f6 3196 crWaitUntil(pktin);
3197 if (pktin->type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
32874aea 3198 logevent("CryptoCard authentication declined");
51470298 3199 c_write_str(ssh, "CryptoCard authentication refused.\r\n");
3200 s->ccard_auth_refused = 1;
614a20a0 3201 continue;
32874aea 3202 } else {
0016d70b 3203 char *challenge;
3204 int challengelen;
3205
ff3187f6 3206 ssh_pkt_getstring(pktin, &challenge, &challengelen);
0016d70b 3207 if (!challenge) {
3208 bombout(("CryptoCard challenge packet was badly formed"));
3209 crStop(0);
3210 }
32874aea 3211 logevent("Received CryptoCard challenge");
51470298 3212 if (challengelen > sizeof(s->prompt) - 1)
3213 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
0016d70b 3214 memcpy(s->prompt, challenge, challengelen);
51470298 3215 strncpy(s->prompt + challengelen,
3216 memchr(s->prompt, '\n', challengelen) ?
614a20a0 3217 "" : "\r\nResponse: ",
51470298 3218 sizeof(s->prompt) - challengelen);
3219 s->prompt[sizeof(s->prompt) - 1] = '\0';
32874aea 3220 }
3221 }
51470298 3222 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
3223 sprintf(s->prompt, "%.90s@%.90s's password: ",
3224 s->username, ssh->savedhost);
32874aea 3225 }
51470298 3226 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
32874aea 3227 char *comment = NULL;
231ee168 3228 int type;
3229 char msgbuf[256];
32874aea 3230 if (flags & FLAG_VERBOSE)
51470298 3231 c_write_str(ssh, "Trying public key authentication.\r\n");
6c6d9ed9 3232 logeventf(ssh, "Trying public key \"%s\"",
3233 filename_to_str(&ssh->cfg.keyfile));
9a30e26b 3234 type = key_type(&ssh->cfg.keyfile);
231ee168 3235 if (type != SSH_KEYTYPE_SSH1) {
3236 sprintf(msgbuf, "Key is of wrong type (%s)",
3237 key_type_to_str(type));
3238 logevent(msgbuf);
51470298 3239 c_write_str(ssh, msgbuf);
3240 c_write_str(ssh, "\r\n");
3241 s->tried_publickey = 1;
231ee168 3242 continue;
3243 }
9a30e26b 3244 if (!rsakey_encrypted(&ssh->cfg.keyfile, &comment)) {
32874aea 3245 if (flags & FLAG_VERBOSE)
51470298 3246 c_write_str(ssh, "No passphrase required.\r\n");
32874aea 3247 goto tryauth;
3248 }
51470298 3249 sprintf(s->prompt, "Passphrase for key \"%.100s\": ", comment);
32874aea 3250 sfree(comment);
3251 }
a52f067e 3252
614a20a0 3253 /*
3254 * Show password prompt, having first obtained it via a TIS
3255 * or CryptoCard exchange if we're doing TIS or CryptoCard
3256 * authentication.
3257 */
fa17a66e 3258 if (ssh_get_line) {
51470298 3259 if (!ssh_get_line(s->prompt, s->password,
3260 sizeof(s->password), TRUE)) {
32874aea 3261 /*
3262 * get_line failed to get a password (for example
3263 * because one was supplied on the command line
3264 * which has already failed to work). Terminate.
3265 */
51470298 3266 send_packet(ssh, SSH1_MSG_DISCONNECT,
2bc6a386 3267 PKT_STR, "No more passwords available to try",
3268 PKT_END);
247308b5 3269 logevent("Unable to authenticate");
a8327734 3270 connection_fatal(ssh->frontend, "Unable to authenticate");
3bb2f322 3271 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 3272 crStop(1);
32874aea 3273 }
fb09bf1c 3274 } else {
614a20a0 3275 /* Prompt may have come from server. We've munged it a bit, so
3276 * we know it to be zero-terminated at least once. */
51470298 3277 int ret; /* need not be saved over crReturn */
3278 c_write_untrusted(ssh, s->prompt, strlen(s->prompt));
3279 s->pos = 0;
0405e71f 3280
51470298 3281 setup_userpass_input(ssh, s->password, sizeof(s->password), 0);
0405e71f 3282 do {
ff3187f6 3283 crWaitUntil(!pktin);
51470298 3284 ret = process_userpass_input(ssh, in, inlen);
0405e71f 3285 } while (ret == 0);
3286 if (ret < 0)
3287 cleanup_exit(0);
51470298 3288 c_write_str(ssh, "\r\n");
32874aea 3289 }
3290
3291 tryauth:
51470298 3292 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
32874aea 3293 /*
3294 * Try public key authentication with the specified
3295 * key file.
3296 */
51470298 3297 s->tried_publickey = 1;
3298
3299 {
222d54dc 3300 const char *error = NULL;
3301 int ret = loadrsakey(&ssh->cfg.keyfile, &s->key, s->password,
3302 &error);
51470298 3303 if (ret == 0) {
3304 c_write_str(ssh, "Couldn't load private key from ");
9fab77dc 3305 c_write_str(ssh, filename_to_str(&ssh->cfg.keyfile));
222d54dc 3306 c_write_str(ssh, " (");
3307 c_write_str(ssh, error);
3308 c_write_str(ssh, ").\r\n");
51470298 3309 continue; /* go and try password */
3310 }
3311 if (ret == -1) {
3312 c_write_str(ssh, "Wrong passphrase.\r\n");
3313 s->tried_publickey = 0;
3314 continue; /* try again */
3315 }
32874aea 3316 }
3317
3318 /*
3319 * Send a public key attempt.
3320 */
51470298 3321 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
3322 PKT_BIGNUM, s->key.modulus, PKT_END);
32874aea 3323
ff3187f6 3324 crWaitUntil(pktin);
3325 if (pktin->type == SSH1_SMSG_FAILURE) {
51470298 3326 c_write_str(ssh, "Server refused our public key.\r\n");
32874aea 3327 continue; /* go and try password */
3328 }
ff3187f6 3329 if (pktin->type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
6b5cf8b4 3330 bombout(("Bizarre response to offer of public key"));
7ffdbc1a 3331 crStop(0);
32874aea 3332 }
32874aea 3333
51470298 3334 {
3335 int i;
3336 unsigned char buffer[32];
3337 Bignum challenge, response;
3338
ff3187f6 3339 if ((challenge = ssh1_pkt_getmp(pktin)) == NULL) {
0016d70b 3340 bombout(("Server's RSA challenge was badly formatted"));
3341 crStop(0);
3342 }
51470298 3343 response = rsadecrypt(challenge, &s->key);
3344 freebn(s->key.private_exponent);/* burn the evidence */
32874aea 3345
51470298 3346 for (i = 0; i < 32; i++) {
3347 buffer[i] = bignum_byte(response, 31 - i);
3348 }
3349
3350 MD5Init(&md5c);
3351 MD5Update(&md5c, buffer, 32);
3352 MD5Update(&md5c, s->session_id, 16);
3353 MD5Final(buffer, &md5c);
32874aea 3354
51470298 3355 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
3356 PKT_DATA, buffer, 16, PKT_END);
3357
3358 freebn(challenge);
3359 freebn(response);
3360 }
32874aea 3361
ff3187f6 3362 crWaitUntil(pktin);
3363 if (pktin->type == SSH1_SMSG_FAILURE) {
32874aea 3364 if (flags & FLAG_VERBOSE)
51470298 3365 c_write_str(ssh, "Failed to authenticate with"
3366 " our public key.\r\n");
32874aea 3367 continue; /* go and try password */
ff3187f6 3368 } else if (pktin->type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 3369 bombout(("Bizarre response to RSA authentication response"));
7ffdbc1a 3370 crStop(0);
32874aea 3371 }
3372
3373 break; /* we're through! */
3374 } else {
51470298 3375 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
32874aea 3376 /*
3377 * Defence against traffic analysis: we send a
3378 * whole bunch of packets containing strings of
3379 * different lengths. One of these strings is the
3380 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3381 * The others are all random data in
3382 * SSH1_MSG_IGNORE packets. This way a passive
3383 * listener can't tell which is the password, and
3384 * hence can't deduce the password length.
3385 *
3386 * Anybody with a password length greater than 16
3387 * bytes is going to have enough entropy in their
3388 * password that a listener won't find it _that_
3389 * much help to know how long it is. So what we'll
3390 * do is:
3391 *
3392 * - if password length < 16, we send 15 packets
3393 * containing string lengths 1 through 15
3394 *
3395 * - otherwise, we let N be the nearest multiple
3396 * of 8 below the password length, and send 8
3397 * packets containing string lengths N through
3398 * N+7. This won't obscure the order of
3399 * magnitude of the password length, but it will
3400 * introduce a bit of extra uncertainty.
3401 *
3402 * A few servers (the old 1.2.18 through 1.2.22)
3403 * can't deal with SSH1_MSG_IGNORE. For these
3404 * servers, we need an alternative defence. We make
3405 * use of the fact that the password is interpreted
3406 * as a C string: so we can append a NUL, then some
3407 * random data.
bd358db1 3408 *
3409 * One server (a Cisco one) can deal with neither
3410 * SSH1_MSG_IGNORE _nor_ a padded password string.
3411 * For this server we are left with no defences
3412 * against password length sniffing.
32874aea 3413 */
51470298 3414 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE)) {
b17c8428 3415 /*
3416 * The server can deal with SSH1_MSG_IGNORE, so
3417 * we can use the primary defence.
3418 */
32874aea 3419 int bottom, top, pwlen, i;
3420 char *randomstr;
3421
51470298 3422 pwlen = strlen(s->password);
32874aea 3423 if (pwlen < 16) {
3424 bottom = 0; /* zero length passwords are OK! :-) */
3425 top = 15;
3426 } else {
3427 bottom = pwlen & ~7;
3428 top = bottom + 7;
3429 }
3430
3431 assert(pwlen >= bottom && pwlen <= top);
3432
3d88e64d 3433 randomstr = snewn(top + 1, char);
32874aea 3434
3435 for (i = bottom; i <= top; i++) {
9a10ecf4 3436 if (i == pwlen) {
51470298 3437 defer_packet(ssh, s->pwpkt_type,
9a10ecf4 3438 PKTT_PASSWORD, PKT_STR, s->password,
3439 PKTT_OTHER, PKT_END);
3440 } else {
32874aea 3441 for (j = 0; j < i; j++) {
3442 do {
3443 randomstr[j] = random_byte();
3444 } while (randomstr[j] == '\0');
3445 }
3446 randomstr[i] = '\0';
51470298 3447 defer_packet(ssh, SSH1_MSG_IGNORE,
32874aea 3448 PKT_STR, randomstr, PKT_END);
3449 }
3450 }
bd358db1 3451 logevent("Sending password with camouflage packets");
51470298 3452 ssh_pkt_defersend(ssh);
679539d7 3453 sfree(randomstr);
bd358db1 3454 }
51470298 3455 else if (!(ssh->remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
b17c8428 3456 /*
3457 * The server can't deal with SSH1_MSG_IGNORE
3458 * but can deal with padded passwords, so we
3459 * can use the secondary defence.
3460 */
bd358db1 3461 char string[64];
51470298 3462 char *ss;
bd358db1 3463 int len;
3464
51470298 3465 len = strlen(s->password);
bd358db1 3466 if (len < sizeof(string)) {
51470298 3467 ss = string;
3468 strcpy(string, s->password);
bd358db1 3469 len++; /* cover the zero byte */
3470 while (len < sizeof(string)) {
3471 string[len++] = (char) random_byte();
3472 }
3473 } else {
51470298 3474 ss = s->password;
bd358db1 3475 }
3476 logevent("Sending length-padded password");
9a10ecf4 3477 send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
3478 PKT_INT, len, PKT_DATA, ss, len,
3479 PKTT_OTHER, PKT_END);
bd358db1 3480 } else {
3481 /*
3482 * The server has _both_
3483 * BUG_CHOKES_ON_SSH1_IGNORE and
3484 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3485 * therefore nothing we can do.
3486 */
3487 int len;
51470298 3488 len = strlen(s->password);
bd358db1 3489 logevent("Sending unpadded password");
9a10ecf4 3490 send_packet(ssh, s->pwpkt_type,
3491 PKTT_PASSWORD, PKT_INT, len,
3492 PKT_DATA, s->password, len,
3493 PKTT_OTHER, PKT_END);
32874aea 3494 }
3495 } else {
9a10ecf4 3496 send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
3497 PKT_STR, s->password, PKTT_OTHER, PKT_END);
32874aea 3498 }
3499 }
c5e9c988 3500 logevent("Sent password");
51470298 3501 memset(s->password, 0, strlen(s->password));
ff3187f6 3502 crWaitUntil(pktin);
3503 if (pktin->type == SSH1_SMSG_FAILURE) {
32874aea 3504 if (flags & FLAG_VERBOSE)
51470298 3505 c_write_str(ssh, "Access denied\r\n");
c5e9c988 3506 logevent("Authentication refused");
ff3187f6 3507 } else if (pktin->type != SSH1_SMSG_SUCCESS) {
3508 bombout(("Strange packet received, type %d", pktin->type));
7ffdbc1a 3509 crStop(0);
374330e2 3510 }
3511 }
3512
c5e9c988 3513 logevent("Authentication successful");
3514
fb09bf1c 3515 crFinish(1);
3516}
3517
32874aea 3518void sshfwd_close(struct ssh_channel *c)
3519{
51470298 3520 Ssh ssh = c->ssh;
3521
36f94d1f 3522 if (ssh->state != SSH_STATE_SESSION) {
3523 assert(ssh->state == SSH_STATE_CLOSED);
3524 return;
3525 }
3526
80e48603 3527 if (c && !c->closes) {
4ed34d25 3528 /*
3529 * If the channel's remoteid is -1, we have sent
3530 * CHANNEL_OPEN for this channel, but it hasn't even been
3531 * acknowledged by the server. So we must set a close flag
3532 * on it now, and then when the server acks the channel
3533 * open, we can close it then.
3534 */
36cac739 3535 if (((int)c->remoteid) != -1) {
51470298 3536 if (ssh->version == 1) {
3537 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid,
4ed34d25 3538 PKT_END);
3539 } else {
ff3187f6 3540 struct Packet *pktout;
3541 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
3542 ssh2_pkt_adduint32(pktout, c->remoteid);
3543 ssh2_pkt_send(ssh, pktout);
4ed34d25 3544 }
32874aea 3545 }
0357890f 3546 c->closes = 1; /* sent MSG_CLOSE */
32874aea 3547 if (c->type == CHAN_X11) {
3548 c->u.x11.s = NULL;
d74d141c 3549 logevent("Forwarded X11 connection terminated");
4ed34d25 3550 } else if (c->type == CHAN_SOCKDATA ||
3551 c->type == CHAN_SOCKDATA_DORMANT) {
d74d141c 3552 c->u.pfd.s = NULL;
3553 logevent("Forwarded port closed");
32874aea 3554 }
3555 }
3556}
3557
5471d09a 3558int sshfwd_write(struct ssh_channel *c, char *buf, int len)
32874aea 3559{
51470298 3560 Ssh ssh = c->ssh;
3561
36f94d1f 3562 if (ssh->state != SSH_STATE_SESSION) {
3563 assert(ssh->state == SSH_STATE_CLOSED);
3564 return 0;
3565 }
3566
51470298 3567 if (ssh->version == 1) {
3568 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
32874aea 3569 PKT_INT, c->remoteid,
9a10ecf4 3570 PKTT_DATA,
3571 PKT_INT, len, PKT_DATA, buf, len,
3572 PKTT_OTHER, PKT_END);
5471d09a 3573 /*
3574 * In SSH1 we can return 0 here - implying that forwarded
3575 * connections are never individually throttled - because
3576 * the only circumstance that can cause throttling will be
3577 * the whole SSH connection backing up, in which case
3578 * _everything_ will be throttled as a whole.
3579 */
3580 return 0;
783415f8 3581 } else {
32874aea 3582 ssh2_add_channel_data(c, buf, len);
5471d09a 3583 return ssh2_try_send(c);
3584 }
3585}
3586
3587void sshfwd_unthrottle(struct ssh_channel *c, int bufsize)
3588{
51470298 3589 Ssh ssh = c->ssh;
3590
36f94d1f 3591 if (ssh->state != SSH_STATE_SESSION) {
3592 assert(ssh->state == SSH_STATE_CLOSED);
3593 return;
3594 }
3595
51470298 3596 if (ssh->version == 1) {
5471d09a 3597 if (c->v.v1.throttling && bufsize < SSH1_BUFFER_LIMIT) {
3598 c->v.v1.throttling = 0;
51470298 3599 ssh1_throttle(ssh, -1);
5471d09a 3600 }
3601 } else {
3602 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
783415f8 3603 }
9c964e85 3604}
3605
06fadff5 3606static void ssh_queueing_handler(Ssh ssh, struct Packet *pktin)
3607{
3608 struct queued_handler *qh = ssh->qhead;
3609
3610 assert(qh != NULL);
3611
3612 assert(pktin->type == qh->msg1 || pktin->type == qh->msg2);
3613
3614 if (qh->msg1 > 0) {
3615 assert(ssh->packet_dispatch[qh->msg1] == ssh_queueing_handler);
3616 ssh->packet_dispatch[qh->msg1] = NULL;
3617 }
3618 if (qh->msg2 > 0) {
3619 assert(ssh->packet_dispatch[qh->msg2] == ssh_queueing_handler);
3620 ssh->packet_dispatch[qh->msg2] = NULL;
3621 }
3622
3623 if (qh->next) {
3624 ssh->qhead = qh->next;
3625
3626 if (ssh->qhead->msg1 > 0) {
3627 assert(ssh->packet_dispatch[ssh->qhead->msg1] == NULL);
3628 ssh->packet_dispatch[ssh->qhead->msg1] = ssh_queueing_handler;
3629 }
3630 if (ssh->qhead->msg2 > 0) {
3631 assert(ssh->packet_dispatch[ssh->qhead->msg2] == NULL);
3632 ssh->packet_dispatch[ssh->qhead->msg2] = ssh_queueing_handler;
3633 }
3634 } else {
3635 ssh->qhead = ssh->qtail = NULL;
3636 ssh->packet_dispatch[pktin->type] = NULL;
3637 }
3638
3639 qh->handler(ssh, pktin, qh->ctx);
3640
3641 sfree(qh);
3642}
3643
3644static void ssh_queue_handler(Ssh ssh, int msg1, int msg2,
3645 chandler_fn_t handler, void *ctx)
3646{
3647 struct queued_handler *qh;
3648
3649 qh = snew(struct queued_handler);
3650 qh->msg1 = msg1;
3651 qh->msg2 = msg2;
3652 qh->handler = handler;
3653 qh->ctx = ctx;
3654 qh->next = NULL;
3655
3656 if (ssh->qtail == NULL) {
3657 ssh->qhead = qh;
3658
3659 if (qh->msg1 > 0) {
3660 assert(ssh->packet_dispatch[qh->msg1] == NULL);
3661 ssh->packet_dispatch[qh->msg1] = ssh_queueing_handler;
3662 }
3663 if (qh->msg2 > 0) {
3664 assert(ssh->packet_dispatch[qh->msg2] == NULL);
3665 ssh->packet_dispatch[qh->msg2] = ssh_queueing_handler;
3666 }
3667 } else {
3668 ssh->qtail->next = qh;
3669 }
3670 ssh->qtail = qh;
3671}
3672
3673static void ssh_rportfwd_succfail(Ssh ssh, struct Packet *pktin, void *ctx)
3674{
3675 struct ssh_rportfwd *rpf, *pf = (struct ssh_rportfwd *)ctx;
3676
3677 if (pktin->type == (ssh->version == 1 ? SSH1_SMSG_SUCCESS :
3678 SSH2_MSG_REQUEST_SUCCESS)) {
3679 logeventf(ssh, "Remote port forwarding from %s enabled",
3680 pf->sportdesc);
3681 } else {
3682 logeventf(ssh, "Remote port forwarding from %s refused",
3683 pf->sportdesc);
3684
3685 rpf = del234(ssh->rportfwds, pf);
3686 assert(rpf == pf);
fda2feb1 3687 free_rportfwd(pf);
06fadff5 3688 }
3689}
3690
3691static void ssh_setup_portfwd(Ssh ssh, const Config *cfg)
3692{
84328ddb 3693 const char *portfwd_strptr = cfg->portfwd;
3694 struct ssh_portfwd *epf;
3695 int i;
06fadff5 3696
fda2feb1 3697 if (!ssh->portfwds) {
3698 ssh->portfwds = newtree234(ssh_portcmp);
3699 } else {
3700 /*
3701 * Go through the existing port forwardings and tag them
84328ddb 3702 * with status==DESTROY. Any that we want to keep will be
3703 * re-enabled (status==KEEP) as we go through the
3704 * configuration and find out which bits are the same as
3705 * they were before.
fda2feb1 3706 */
3707 struct ssh_portfwd *epf;
3708 int i;
3709 for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
84328ddb 3710 epf->status = DESTROY;
fda2feb1 3711 }
3712
06fadff5 3713 while (*portfwd_strptr) {
84328ddb 3714 char address_family, type;
3715 int sport,dport,sserv,dserv;
3716 char sports[256], dports[256], saddr[256], host[256];
3717 int n;
3718
05581745 3719 address_family = 'A';
3720 type = 'L';
84328ddb 3721 if (*portfwd_strptr == 'A' ||
3722 *portfwd_strptr == '4' ||
3723 *portfwd_strptr == '6')
3724 address_family = *portfwd_strptr++;
3725 if (*portfwd_strptr == 'L' ||
3726 *portfwd_strptr == 'R' ||
3727 *portfwd_strptr == 'D')
3728 type = *portfwd_strptr++;
05581745 3729
06fadff5 3730 saddr[0] = '\0';
05581745 3731
06fadff5 3732 n = 0;
3733 while (*portfwd_strptr && *portfwd_strptr != '\t') {
3734 if (*portfwd_strptr == ':') {
3735 /*
3736 * We've seen a colon in the middle of the
3737 * source port number. This means that
3738 * everything we've seen until now is the
3739 * source _address_, so we'll move it into
3740 * saddr and start sports from the beginning
3741 * again.
3742 */
3743 portfwd_strptr++;
3744 sports[n] = '\0';
3745 if (ssh->version == 1 && type == 'R') {
3746 logeventf(ssh, "SSH1 cannot handle remote source address "
3747 "spec \"%s\"; ignoring", sports);
3748 } else
3749 strcpy(saddr, sports);
3750 n = 0;
3751 }
3752 if (n < 255) sports[n++] = *portfwd_strptr++;
3753 }
3754 sports[n] = 0;
3755 if (type != 'D') {
3756 if (*portfwd_strptr == '\t')
3757 portfwd_strptr++;
3758 n = 0;
3759 while (*portfwd_strptr && *portfwd_strptr != ':') {
3760 if (n < 255) host[n++] = *portfwd_strptr++;
3761 }
3762 host[n] = 0;
3763 if (*portfwd_strptr == ':')
3764 portfwd_strptr++;
3765 n = 0;
3766 while (*portfwd_strptr) {
3767 if (n < 255) dports[n++] = *portfwd_strptr++;
3768 }
3769 dports[n] = 0;
3770 portfwd_strptr++;
3771 dport = atoi(dports);
3772 dserv = 0;
3773 if (dport == 0) {
3774 dserv = 1;
3775 dport = net_service_lookup(dports);
3776 if (!dport) {
3777 logeventf(ssh, "Service lookup failed for destination"
3778 " port \"%s\"", dports);
3779 }
3780 }
3781 } else {
3782 while (*portfwd_strptr) portfwd_strptr++;
3783 dport = dserv = -1;
3784 portfwd_strptr++; /* eat the NUL and move to next one */
3785 }
3786 sport = atoi(sports);
3787 sserv = 0;
3788 if (sport == 0) {
3789 sserv = 1;
3790 sport = net_service_lookup(sports);
3791 if (!sport) {
3792 logeventf(ssh, "Service lookup failed for source"
3793 " port \"%s\"", sports);
3794 }
3795 }
3796 if (sport && dport) {
3797 /* Set up a description of the source port. */
fda2feb1 3798 struct ssh_portfwd *pfrec, *epfrec;
fda2feb1 3799
3800 pfrec = snew(struct ssh_portfwd);
3801 pfrec->type = type;
3802 pfrec->saddr = *saddr ? dupstr(saddr) : NULL;
3fe92132 3803 pfrec->sserv = sserv ? dupstr(sports) : NULL;
fda2feb1 3804 pfrec->sport = sport;
84328ddb 3805 pfrec->daddr = *host ? dupstr(host) : NULL;
3fe92132 3806 pfrec->dserv = dserv ? dupstr(dports) : NULL;
fda2feb1 3807 pfrec->dport = dport;
3808 pfrec->local = NULL;
3809 pfrec->remote = NULL;
05581745 3810 pfrec->addressfamily = (address_family == '4' ? ADDRTYPE_IPV4 :
3811 address_family == '6' ? ADDRTYPE_IPV6 :
3812 ADDRTYPE_UNSPEC);
fda2feb1 3813
3814 epfrec = add234(ssh->portfwds, pfrec);
3815 if (epfrec != pfrec) {
3816 /*
3817 * We already have a port forwarding with precisely
3818 * these parameters. Hence, no need to do anything;
84328ddb 3819 * simply tag the existing one as KEEP.
fda2feb1 3820 */
84328ddb 3821 epfrec->status = KEEP;
fda2feb1 3822 free_portfwd(pfrec);
84328ddb 3823 } else {
3824 pfrec->status = CREATE;
3825 }
3826 }
3827 }
3828
3829 /*
3830 * Now go through and destroy any port forwardings which were
3831 * not re-enabled.
3832 */
3833 for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
3834 if (epf->status == DESTROY) {
3835 char *message;
3836
3837 message = dupprintf("%s port forwarding from %s%s%d",
3838 epf->type == 'L' ? "local" :
3839 epf->type == 'R' ? "remote" : "dynamic",
3840 epf->saddr ? epf->saddr : "",
3841 epf->saddr ? ":" : "",
3842 epf->sport);
3843
3844 if (epf->type != 'D') {
3845 char *msg2 = dupprintf("%s to %s:%d", message,
3846 epf->daddr, epf->dport);
3847 sfree(message);
3848 message = msg2;
3849 }
3850
3851 logeventf(ssh, "Cancelling %s", message);
3852 sfree(message);
3853
3854 if (epf->remote) {
3855 struct ssh_rportfwd *rpf = epf->remote;
3856 struct Packet *pktout;
3857
3858 /*
3859 * Cancel the port forwarding at the server
3860 * end.
3861 */
3862 if (ssh->version == 1) {
3863 /*
3864 * We cannot cancel listening ports on the
3865 * server side in SSH1! There's no message
3866 * to support it. Instead, we simply remove
3867 * the rportfwd record from the local end
3868 * so that any connections the server tries
3869 * to make on it are rejected.
3870 */
3871 } else {
3872 pktout = ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST);
3873 ssh2_pkt_addstring(pktout, "cancel-tcpip-forward");
3874 ssh2_pkt_addbool(pktout, 0);/* _don't_ want reply */
3875 if (epf->saddr) {
3876 ssh2_pkt_addstring(pktout, epf->saddr);
3877 } else if (ssh->cfg.rport_acceptall) {
3878 ssh2_pkt_addstring(pktout, "0.0.0.0");
3879 } else {
3880 ssh2_pkt_addstring(pktout, "127.0.0.1");
3881 }
3882 ssh2_pkt_adduint32(pktout, epf->sport);
3883 ssh2_pkt_send(ssh, pktout);
3884 }
3885
3886 del234(ssh->rportfwds, rpf);
3887 free_rportfwd(rpf);
3888 } else if (epf->local) {
3889 pfd_terminate(epf->local);
3890 }
3891
3892 delpos234(ssh->portfwds, i);
3893 free_portfwd(epf);
3894 i--; /* so we don't skip one in the list */
3895 }
3896
3897 /*
3898 * And finally, set up any new port forwardings (status==CREATE).
3899 */
3900 for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
3901 if (epf->status == CREATE) {
3902 char *sportdesc, *dportdesc;
3fe92132 3903 sportdesc = dupprintf("%s%s%s%s%d%s",
84328ddb 3904 epf->saddr ? epf->saddr : "",
3905 epf->saddr ? ":" : "",
3fe92132 3906 epf->sserv ? epf->sserv : "",
3907 epf->sserv ? "(" : "",
3908 epf->sport,
3909 epf->sserv ? ")" : "");
84328ddb 3910 if (epf->type == 'D') {
3911 dportdesc = NULL;
3912 } else {
3fe92132 3913 dportdesc = dupprintf("%s:%s%s%d%s",
3914 epf->daddr,
3915 epf->dserv ? epf->dserv : "",
3916 epf->dserv ? "(" : "",
3917 epf->dport,
3918 epf->dserv ? ")" : "");
84328ddb 3919 }
05581745 3920
84328ddb 3921 if (epf->type == 'L') {
3922 const char *err = pfd_addforward(epf->daddr, epf->dport,
3923 epf->saddr, epf->sport,
3924 ssh, &ssh->cfg,
3925 &epf->local,
3926 epf->addressfamily);
3927
3928 logeventf(ssh, "Local %sport %s forwarding to %s%s%s",
3929 epf->addressfamily == ADDRTYPE_IPV4 ? "IPv4 " :
3930 epf->addressfamily == ADDRTYPE_IPV6 ? "IPv6 " : "",
3931 sportdesc, dportdesc,
3932 err ? " failed: " : "", err ? err : "");
3933 } else if (epf->type == 'D') {
06fadff5 3934 const char *err = pfd_addforward(NULL, -1,
84328ddb 3935 epf->saddr, epf->sport,
3936 ssh, &ssh->cfg,
3937 &epf->local,
3938 epf->addressfamily);
3939
3940 logeventf(ssh, "Local %sport %s SOCKS dynamic forwarding%s%s",
3941 epf->addressfamily == ADDRTYPE_IPV4 ? "IPv4 " :
3942 epf->addressfamily == ADDRTYPE_IPV6 ? "IPv6 " : "",
3943 sportdesc,
3944 err ? " failed: " : "", err ? err : "");
06fadff5 3945 } else {
3946 struct ssh_rportfwd *pf;
3947
3948 /*
3949 * Ensure the remote port forwardings tree exists.
3950 */
3951 if (!ssh->rportfwds) {
3952 if (ssh->version == 1)
3953 ssh->rportfwds = newtree234(ssh_rportcmp_ssh1);
3954 else
3955 ssh->rportfwds = newtree234(ssh_rportcmp_ssh2);
3956 }
3957
3958 pf = snew(struct ssh_rportfwd);
84328ddb 3959 strncpy(pf->dhost, epf->daddr, lenof(pf->dhost)-1);
3960 pf->dhost[lenof(pf->dhost)-1] = '\0';
3961 pf->dport = epf->dport;
3962 pf->sport = epf->sport;
06fadff5 3963 if (add234(ssh->rportfwds, pf) != pf) {
3964 logeventf(ssh, "Duplicate remote port forwarding to %s:%d",
84328ddb 3965 epf->daddr, epf->dport);
06fadff5 3966 sfree(pf);
3967 } else {
3968 logeventf(ssh, "Requesting remote port %s"
84328ddb 3969 " forward to %s", sportdesc, dportdesc);
06fadff5 3970
3971 pf->sportdesc = sportdesc;
3972 sportdesc = NULL;
84328ddb 3973 epf->remote = pf;
3974 pf->pfrec = epf;
06fadff5 3975
3976 if (ssh->version == 1) {
3977 send_packet(ssh, SSH1_CMSG_PORT_FORWARD_REQUEST,
84328ddb 3978 PKT_INT, epf->sport,
3979 PKT_STR, epf->daddr,
3980 PKT_INT, epf->dport,
06fadff5 3981 PKT_END);
3982 ssh_queue_handler(ssh, SSH1_SMSG_SUCCESS,
3983 SSH1_SMSG_FAILURE,
3984 ssh_rportfwd_succfail, pf);
3985 } else {
3986 struct Packet *pktout;
3987 pktout = ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST);
3988 ssh2_pkt_addstring(pktout, "tcpip-forward");
3989 ssh2_pkt_addbool(pktout, 1);/* want reply */
84328ddb 3990 if (epf->saddr) {
3991 ssh2_pkt_addstring(pktout, epf->saddr);
06fadff5 3992 } else if (ssh->cfg.rport_acceptall) {
3993 ssh2_pkt_addstring(pktout, "0.0.0.0");
3994 } else {
3995 ssh2_pkt_addstring(pktout, "127.0.0.1");
3996 }
84328ddb 3997 ssh2_pkt_adduint32(pktout, epf->sport);
06fadff5 3998 ssh2_pkt_send(ssh, pktout);
3999
4000 ssh_queue_handler(ssh, SSH2_MSG_REQUEST_SUCCESS,
4001 SSH2_MSG_REQUEST_FAILURE,
4002 ssh_rportfwd_succfail, pf);
4003 }
4004 }
4005 }
4006 sfree(sportdesc);
84328ddb 4007 sfree(dportdesc);
06fadff5 4008 }
06fadff5 4009}
4010
51df0ab5 4011static void ssh1_smsg_stdout_stderr_data(Ssh ssh, struct Packet *pktin)
4012{
4013 char *string;
4014 int stringlen, bufsize;
4015
4016 ssh_pkt_getstring(pktin, &string, &stringlen);
4017 if (string == NULL) {
4018 bombout(("Incoming terminal data packet was badly formed"));
4019 return;
4020 }
4021
4022 bufsize = from_backend(ssh->frontend, pktin->type == SSH1_SMSG_STDERR_DATA,
4023 string, stringlen);
4024 if (!ssh->v1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
4025 ssh->v1_stdout_throttling = 1;
4026 ssh1_throttle(ssh, +1);
4027 }
4028}
4029
4030static void ssh1_smsg_x11_open(Ssh ssh, struct Packet *pktin)
4031{
4032 /* Remote side is trying to open a channel to talk to our
4033 * X-Server. Give them back a local channel number. */
4034 struct ssh_channel *c;
4035 int remoteid = ssh_pkt_getuint32(pktin);
4036
4037 logevent("Received X11 connect request");
4038 /* Refuse if X11 forwarding is disabled. */
4039 if (!ssh->X11_fwd_enabled) {
4040 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4041 PKT_INT, remoteid, PKT_END);
4042 logevent("Rejected X11 connect request");
4043 } else {
4044 c = snew(struct ssh_channel);
4045 c->ssh = ssh;
4046
4047 if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
4048 ssh->x11auth, NULL, -1, &ssh->cfg) != NULL) {
4049 logevent("Opening X11 forward connection failed");
4050 sfree(c);
4051 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4052 PKT_INT, remoteid, PKT_END);
4053 } else {
4054 logevent
4055 ("Opening X11 forward connection succeeded");
4056 c->remoteid = remoteid;
4057 c->localid = alloc_channel_id(ssh);
4058 c->closes = 0;
4059 c->v.v1.throttling = 0;
4060 c->type = CHAN_X11; /* identify channel type */
4061 add234(ssh->channels, c);
4062 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
4063 PKT_INT, c->remoteid, PKT_INT,
4064 c->localid, PKT_END);
4065 logevent("Opened X11 forward channel");
4066 }
4067 }
4068}
4069
4070static void ssh1_smsg_agent_open(Ssh ssh, struct Packet *pktin)
4071{
4072 /* Remote side is trying to open a channel to talk to our
4073 * agent. Give them back a local channel number. */
4074 struct ssh_channel *c;
4075 int remoteid = ssh_pkt_getuint32(pktin);
4076
4077 /* Refuse if agent forwarding is disabled. */
4078 if (!ssh->agentfwd_enabled) {
4079 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4080 PKT_INT, remoteid, PKT_END);
4081 } else {
4082 c = snew(struct ssh_channel);
4083 c->ssh = ssh;
4084 c->remoteid = remoteid;
4085 c->localid = alloc_channel_id(ssh);
4086 c->closes = 0;
4087 c->v.v1.throttling = 0;
4088 c->type = CHAN_AGENT; /* identify channel type */
4089 c->u.a.lensofar = 0;
4090 add234(ssh->channels, c);
4091 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
4092 PKT_INT, c->remoteid, PKT_INT, c->localid,
4093 PKT_END);
4094 }
4095}
4096
4097static void ssh1_msg_port_open(Ssh ssh, struct Packet *pktin)
4098{
4099 /* Remote side is trying to open a channel to talk to a
4100 * forwarded port. Give them back a local channel number. */
4101 struct ssh_channel *c;
05581745 4102 struct ssh_rportfwd pf, *pfp;
51df0ab5 4103 int remoteid;
4104 int hostsize, port;
4105 char *host, buf[1024];
4106 const char *e;
4107 c = snew(struct ssh_channel);
4108 c->ssh = ssh;
4109
4110 remoteid = ssh_pkt_getuint32(pktin);
4111 ssh_pkt_getstring(pktin, &host, &hostsize);
4112 port = ssh_pkt_getuint32(pktin);
4113
4114 if (hostsize >= lenof(pf.dhost))
4115 hostsize = lenof(pf.dhost)-1;
4116 memcpy(pf.dhost, host, hostsize);
4117 pf.dhost[hostsize] = '\0';
4118 pf.dport = port;
05581745 4119 pfp = find234(ssh->rportfwds, &pf, NULL);
51df0ab5 4120
05581745 4121 if (pfp == NULL) {
51df0ab5 4122 sprintf(buf, "Rejected remote port open request for %s:%d",
4123 pf.dhost, port);
4124 logevent(buf);
4125 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4126 PKT_INT, remoteid, PKT_END);
4127 } else {
4128 sprintf(buf, "Received remote port open request for %s:%d",
4129 pf.dhost, port);
4130 logevent(buf);
4131 e = pfd_newconnect(&c->u.pfd.s, pf.dhost, port,
05581745 4132 c, &ssh->cfg, pfp->pfrec->addressfamily);
51df0ab5 4133 if (e != NULL) {
4134 char buf[256];
4135 sprintf(buf, "Port open failed: %s", e);
4136 logevent(buf);
4137 sfree(c);
4138 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4139 PKT_INT, remoteid, PKT_END);
4140 } else {
4141 c->remoteid = remoteid;
4142 c->localid = alloc_channel_id(ssh);
4143 c->closes = 0;
4144 c->v.v1.throttling = 0;
4145 c->type = CHAN_SOCKDATA; /* identify channel type */
4146 add234(ssh->channels, c);
4147 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
4148 PKT_INT, c->remoteid, PKT_INT,
4149 c->localid, PKT_END);
4150 logevent("Forwarded port opened successfully");
4151 }
4152 }
4153}
4154
4155static void ssh1_msg_channel_open_confirmation(Ssh ssh, struct Packet *pktin)
4156{
4157 unsigned int remoteid = ssh_pkt_getuint32(pktin);
4158 unsigned int localid = ssh_pkt_getuint32(pktin);
4159 struct ssh_channel *c;
4160
4161 c = find234(ssh->channels, &remoteid, ssh_channelfind);
4162 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
4163 c->remoteid = localid;
4164 c->type = CHAN_SOCKDATA;
4165 c->v.v1.throttling = 0;
4166 pfd_confirm(c->u.pfd.s);
4167 }
4168
4169 if (c && c->closes) {
4170 /*
4171 * We have a pending close on this channel,
4172 * which we decided on before the server acked
4173 * the channel open. So now we know the
4174 * remoteid, we can close it again.
4175 */
4176 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE,
4177 PKT_INT, c->remoteid, PKT_END);
4178 }
4179}
4180
4181static void ssh1_msg_channel_open_failure(Ssh ssh, struct Packet *pktin)
4182{
4183 unsigned int remoteid = ssh_pkt_getuint32(pktin);
4184 struct ssh_channel *c;
4185
4186 c = find234(ssh->channels, &remoteid, ssh_channelfind);
4187 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
4188 logevent("Forwarded connection refused by server");
4189 pfd_close(c->u.pfd.s);
4190 del234(ssh->channels, c);
4191 sfree(c);
4192 }
4193}
4194
4195static void ssh1_msg_channel_close(Ssh ssh, struct Packet *pktin)
4196{
4197 /* Remote side closes a channel. */
4198 unsigned i = ssh_pkt_getuint32(pktin);
4199 struct ssh_channel *c;
4200 c = find234(ssh->channels, &i, ssh_channelfind);
4201 if (c && ((int)c->remoteid) != -1) {
4202 int closetype;
4203 closetype =
4204 (pktin->type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
4205
4206 if ((c->closes == 0) && (c->type == CHAN_X11)) {
4207 logevent("Forwarded X11 connection terminated");
4208 assert(c->u.x11.s != NULL);
4209 x11_close(c->u.x11.s);
4210 c->u.x11.s = NULL;
4211 }
4212 if ((c->closes == 0) && (c->type == CHAN_SOCKDATA)) {
4213 logevent("Forwarded port closed");
4214 assert(c->u.pfd.s != NULL);
4215 pfd_close(c->u.pfd.s);
4216 c->u.pfd.s = NULL;
4217 }
4218
4219 c->closes |= (closetype << 2); /* seen this message */
4220 if (!(c->closes & closetype)) {
4221 send_packet(ssh, pktin->type, PKT_INT, c->remoteid,
4222 PKT_END);
4223 c->closes |= closetype; /* sent it too */
4224 }
4225
4226 if (c->closes == 15) {
4227 del234(ssh->channels, c);
4228 sfree(c);
4229 }
4230 } else {
4231 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
4232 pktin->type == SSH1_MSG_CHANNEL_CLOSE ? "" :
4233 "_CONFIRMATION", c ? "half-open" : "nonexistent",
4234 i));
4235 }
4236}
4237
4238static void ssh1_msg_channel_data(Ssh ssh, struct Packet *pktin)
4239{
4240 /* Data sent down one of our channels. */
4241 int i = ssh_pkt_getuint32(pktin);
4242 char *p;
aa63ab7e 4243 unsigned int len;
51df0ab5 4244 struct ssh_channel *c;
4245
4246 ssh_pkt_getstring(pktin, &p, &len);
4247
4248 c = find234(ssh->channels, &i, ssh_channelfind);
4249 if (c) {
4250 int bufsize = 0;
4251 switch (c->type) {
4252 case CHAN_X11:
4253 bufsize = x11_send(c->u.x11.s, p, len);
4254 break;
4255 case CHAN_SOCKDATA:
4256 bufsize = pfd_send(c->u.pfd.s, p, len);
4257 break;
4258 case CHAN_AGENT:
4259 /* Data for an agent message. Buffer it. */
4260 while (len > 0) {
4261 if (c->u.a.lensofar < 4) {
aa63ab7e 4262 unsigned int l = min(4 - c->u.a.lensofar, len);
51df0ab5 4263 memcpy(c->u.a.msglen + c->u.a.lensofar, p,
4264 l);
4265 p += l;
4266 len -= l;
4267 c->u.a.lensofar += l;
4268 }
4269 if (c->u.a.lensofar == 4) {
4270 c->u.a.totallen =
4271 4 + GET_32BIT(c->u.a.msglen);
4272 c->u.a.message = snewn(c->u.a.totallen,
4273 unsigned char);
4274 memcpy(c->u.a.message, c->u.a.msglen, 4);
4275 }
4276 if (c->u.a.lensofar >= 4 && len > 0) {
aa63ab7e 4277 unsigned int l =
51df0ab5 4278 min(c->u.a.totallen - c->u.a.lensofar,
4279 len);
4280 memcpy(c->u.a.message + c->u.a.lensofar, p,
4281 l);
4282 p += l;
4283 len -= l;
4284 c->u.a.lensofar += l;
4285 }
4286 if (c->u.a.lensofar == c->u.a.totallen) {
4287 void *reply;
4288 int replylen;
4289 if (agent_query(c->u.a.message,
4290 c->u.a.totallen,
4291 &reply, &replylen,
4292 ssh_agentf_callback, c))
4293 ssh_agentf_callback(c, reply, replylen);
4294 sfree(c->u.a.message);
4295 c->u.a.lensofar = 0;
4296 }
4297 }
4298 bufsize = 0; /* agent channels never back up */
4299 break;
4300 }
4301 if (!c->v.v1.throttling && bufsize > SSH1_BUFFER_LIMIT) {
4302 c->v.v1.throttling = 1;
4303 ssh1_throttle(ssh, +1);
4304 }
4305 }
4306}
4307
4308static void ssh1_smsg_exit_status(Ssh ssh, struct Packet *pktin)
4309{
4310 char buf[100];
4311 ssh->exitcode = ssh_pkt_getuint32(pktin);
4312 sprintf(buf, "Server sent command exit status %d",
4313 ssh->exitcode);
4314 logevent(buf);
4315 send_packet(ssh, SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
4316 /*
4317 * In case `helpful' firewalls or proxies tack
4318 * extra human-readable text on the end of the
4319 * session which we might mistake for another
4320 * encrypted packet, we close the session once
4321 * we've sent EXIT_CONFIRMATION.
4322 */
4323 ssh_closing((Plug)ssh, NULL, 0, 0);
4324}
4325
b09eaa88 4326static void do_ssh1_connection(Ssh ssh, unsigned char *in, int inlen,
4327 struct Packet *pktin)
32874aea 4328{
b09eaa88 4329 crBegin(ssh->do_ssh1_connection_crstate);
fb09bf1c 4330
51df0ab5 4331 ssh->packet_dispatch[SSH1_SMSG_STDOUT_DATA] =
4332 ssh->packet_dispatch[SSH1_SMSG_STDERR_DATA] =
4333 ssh1_smsg_stdout_stderr_data;
4334
4335 ssh->packet_dispatch[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION] =
4336 ssh1_msg_channel_open_confirmation;
4337 ssh->packet_dispatch[SSH1_MSG_CHANNEL_OPEN_FAILURE] =
4338 ssh1_msg_channel_open_failure;
4339 ssh->packet_dispatch[SSH1_MSG_CHANNEL_CLOSE] =
4340 ssh->packet_dispatch[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION] =
4341 ssh1_msg_channel_close;
4342 ssh->packet_dispatch[SSH1_MSG_CHANNEL_DATA] = ssh1_msg_channel_data;
4343 ssh->packet_dispatch[SSH1_SMSG_EXIT_STATUS] = ssh1_smsg_exit_status;
4344
86916870 4345 if (ssh->cfg.agentfwd && agent_exists()) {
32874aea 4346 logevent("Requesting agent forwarding");
51470298 4347 send_packet(ssh, SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
32874aea 4348 do {
4349 crReturnV;
ff3187f6 4350 } while (!pktin);
4351 if (pktin->type != SSH1_SMSG_SUCCESS
4352 && pktin->type != SSH1_SMSG_FAILURE) {
6b5cf8b4 4353 bombout(("Protocol confusion"));
7ffdbc1a 4354 crStopV;
ff3187f6 4355 } else if (pktin->type == SSH1_SMSG_FAILURE) {
32874aea 4356 logevent("Agent forwarding refused");
4357 } else {
4358 logevent("Agent forwarding enabled");
51470298 4359 ssh->agentfwd_enabled = TRUE;
51df0ab5 4360 ssh->packet_dispatch[SSH1_SMSG_AGENT_OPEN] = ssh1_smsg_agent_open;
db7d555c 4361 }
dacbd0e8 4362 }
4363
86916870 4364 if (ssh->cfg.x11_forward) {
32874aea 4365 char proto[20], data[64];
4366 logevent("Requesting X11 forwarding");
302121de 4367 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
86916870 4368 data, sizeof(data), ssh->cfg.x11_auth);
4369 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
51470298 4370 if (ssh->v1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) {
4371 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
32874aea 4372 PKT_STR, proto, PKT_STR, data,
86916870 4373 PKT_INT, x11_get_screen_number(ssh->cfg.x11_display),
421d6835 4374 PKT_END);
32874aea 4375 } else {
51470298 4376 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
32874aea 4377 PKT_STR, proto, PKT_STR, data, PKT_END);
4378 }
4379 do {
4380 crReturnV;
ff3187f6 4381 } while (!pktin);
4382 if (pktin->type != SSH1_SMSG_SUCCESS
4383 && pktin->type != SSH1_SMSG_FAILURE) {
6b5cf8b4 4384 bombout(("Protocol confusion"));
7ffdbc1a 4385 crStopV;
ff3187f6 4386 } else if (pktin->type == SSH1_SMSG_FAILURE) {
32874aea 4387 logevent("X11 forwarding refused");
4388 } else {
4389 logevent("X11 forwarding enabled");
51470298 4390 ssh->X11_fwd_enabled = TRUE;
51df0ab5 4391 ssh->packet_dispatch[SSH1_SMSG_X11_OPEN] = ssh1_smsg_x11_open;
9c964e85 4392 }
4393 }
4394
06fadff5 4395 ssh_setup_portfwd(ssh, &ssh->cfg);
4396 ssh->packet_dispatch[SSH1_MSG_PORT_OPEN] = ssh1_msg_port_open;
d74d141c 4397
86916870 4398 if (!ssh->cfg.nopty) {
a5dd8467 4399 /* Unpick the terminal-speed string. */
4400 /* XXX perhaps we should allow no speeds to be sent. */
db219738 4401 ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
4402 sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
a5dd8467 4403 /* Send the pty request. */
51470298 4404 send_packet(ssh, SSH1_CMSG_REQUEST_PTY,
86916870 4405 PKT_STR, ssh->cfg.termtype,
51470298 4406 PKT_INT, ssh->term_height,
4407 PKT_INT, ssh->term_width,
a5dd8467 4408 PKT_INT, 0, PKT_INT, 0, /* width,height in pixels */
db219738 4409 PKT_CHAR, 192, PKT_INT, ssh->ispeed, /* TTY_OP_ISPEED */
4410 PKT_CHAR, 193, PKT_INT, ssh->ospeed, /* TTY_OP_OSPEED */
a5dd8467 4411 PKT_CHAR, 0, PKT_END);
51470298 4412 ssh->state = SSH_STATE_INTERMED;
32874aea 4413 do {
4414 crReturnV;
ff3187f6 4415 } while (!pktin);
4416 if (pktin->type != SSH1_SMSG_SUCCESS
4417 && pktin->type != SSH1_SMSG_FAILURE) {
6b5cf8b4 4418 bombout(("Protocol confusion"));
7ffdbc1a 4419 crStopV;
ff3187f6 4420 } else if (pktin->type == SSH1_SMSG_FAILURE) {
51470298 4421 c_write_str(ssh, "Server refused to allocate pty\r\n");
4422 ssh->editing = ssh->echoing = 1;
32874aea 4423 }
a5dd8467 4424 logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
db219738 4425 ssh->ospeed, ssh->ispeed);
0965bee0 4426 } else {
51470298 4427 ssh->editing = ssh->echoing = 1;
374330e2 4428 }
4429
86916870 4430 if (ssh->cfg.compression) {
51470298 4431 send_packet(ssh, SSH1_CMSG_REQUEST_COMPRESSION, PKT_INT, 6, PKT_END);
32874aea 4432 do {
4433 crReturnV;
ff3187f6 4434 } while (!pktin);
4435 if (pktin->type != SSH1_SMSG_SUCCESS
4436 && pktin->type != SSH1_SMSG_FAILURE) {
6b5cf8b4 4437 bombout(("Protocol confusion"));
7ffdbc1a 4438 crStopV;
ff3187f6 4439 } else if (pktin->type == SSH1_SMSG_FAILURE) {
51470298 4440 c_write_str(ssh, "Server refused to compress\r\n");
32874aea 4441 }
4ba9b64b 4442 logevent("Started compression");
51470298 4443 ssh->v1_compressing = TRUE;
5366aed8 4444 ssh->cs_comp_ctx = zlib_compress_init();
4445 logevent("Initialised zlib (RFC1950) compression");
4446 ssh->sc_comp_ctx = zlib_decompress_init();
4447 logevent("Initialised zlib (RFC1950) decompression");
4ba9b64b 4448 }
4449
fd5e5847 4450 /*
4451 * Start the shell or command.
4452 *
4453 * Special case: if the first-choice command is an SSH2
4454 * subsystem (hence not usable here) and the second choice
4455 * exists, we fall straight back to that.
4456 */
4457 {
86916870 4458 char *cmd = ssh->cfg.remote_cmd_ptr;
fd5e5847 4459
86916870 4460 if (ssh->cfg.ssh_subsys && ssh->cfg.remote_cmd_ptr2) {
4461 cmd = ssh->cfg.remote_cmd_ptr2;
51470298 4462 ssh->fallback_cmd = TRUE;
fd5e5847 4463 }
4464 if (*cmd)
51470298 4465 send_packet(ssh, SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END);
fd5e5847 4466 else
51470298 4467 send_packet(ssh, SSH1_CMSG_EXEC_SHELL, PKT_END);
fd5e5847 4468 logevent("Started session");
4469 }
374330e2 4470
51470298 4471 ssh->state = SSH_STATE_SESSION;
4472 if (ssh->size_needed)
4473 ssh_size(ssh, ssh->term_width, ssh->term_height);
4474 if (ssh->eof_needed)
4475 ssh_special(ssh, TS_EOF);
374330e2 4476
b9d7bcad 4477 if (ssh->ldisc)
4478 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
51470298 4479 ssh->send_ok = 1;
4480 ssh->channels = newtree234(ssh_channelcmp);
374330e2 4481 while (1) {
d74d141c 4482
51df0ab5 4483 /*
4484 * By this point, most incoming packets are already being
4485 * handled by the dispatch table, and we need only pay
4486 * attention to the unusual ones.
4487 */
0357890f 4488
51df0ab5 4489 crReturnV;
4490 if (pktin) {
4491 if (pktin->type == SSH1_SMSG_SUCCESS) {
972a41c8 4492 /* may be from EXEC_SHELL on some servers */
ff3187f6 4493 } else if (pktin->type == SSH1_SMSG_FAILURE) {
972a41c8 4494 /* may be from EXEC_SHELL on some servers
374330e2 4495 * if no pty is available or in other odd cases. Ignore */
374330e2 4496 } else {
ff3187f6 4497 bombout(("Strange packet received: type %d", pktin->type));
7ffdbc1a 4498 crStopV;
374330e2 4499 }
4500 } else {
8df7a775 4501 while (inlen > 0) {
4502 int len = min(inlen, 512);
9a10ecf4 4503 send_packet(ssh, SSH1_CMSG_STDIN_DATA, PKTT_DATA,
4504 PKT_INT, len, PKT_DATA, in, len,
4505 PKTT_OTHER, PKT_END);
8df7a775 4506 in += len;
4507 inlen -= len;
4508 }
374330e2 4509 }
4510 }
4511
4512 crFinishV;
4513}
4514
4515/*
b09eaa88 4516 * Handle the top-level SSH2 protocol.
4517 */
4518static void ssh1_msg_debug(Ssh ssh, struct Packet *pktin)
4519{
4520 char *buf, *msg;
4521 int msglen;
4522
4523 ssh_pkt_getstring(pktin, &msg, &msglen);
4524 buf = dupprintf("Remote debug message: %.*s", msglen, msg);
4525 logevent(buf);
4526 sfree(buf);
4527}
4528
4529static void ssh1_msg_disconnect(Ssh ssh, struct Packet *pktin)
4530{
4531 /* log reason code in disconnect message */
4532 char *msg;
4533 int msglen;
4534
4535 ssh_pkt_getstring(pktin, &msg, &msglen);
4536 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen, msg));
4537}
4538
4539void ssh_msg_ignore(Ssh ssh, struct Packet *pktin)
4540{
4541 /* Do nothing, because we're ignoring it! Duhh. */
4542}
4543
4544static void ssh1_protocol_setup(Ssh ssh)
4545{
4546 int i;
4547
4548 /*
4549 * Most messages are handled by the coroutines.
4550 */
4551 for (i = 0; i < 256; i++)
4552 ssh->packet_dispatch[i] = NULL;
4553
4554 /*
4555 * These special message types we install handlers for.
4556 */
4557 ssh->packet_dispatch[SSH1_MSG_DISCONNECT] = ssh1_msg_disconnect;
4558 ssh->packet_dispatch[SSH1_MSG_IGNORE] = ssh_msg_ignore;
4559 ssh->packet_dispatch[SSH1_MSG_DEBUG] = ssh1_msg_debug;
4560}
4561
4562static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen,
4563 struct Packet *pktin)
4564{
4565 if (ssh->state == SSH_STATE_CLOSED)
4566 return;
4567
4568 if (pktin && ssh->packet_dispatch[pktin->type]) {
4569 ssh->packet_dispatch[pktin->type](ssh, pktin);
4570 return;
4571 }
4572
4573 if (!ssh->protocol_initial_phase_done) {
4574 if (do_ssh1_login(ssh, in, inlen, pktin))
4575 ssh->protocol_initial_phase_done = TRUE;
4576 else
4577 return;
4578 }
4579
4580 do_ssh1_connection(ssh, in, inlen, pktin);
4581}
4582
4583/*
e5574168 4584 * Utility routine for decoding comma-separated strings in KEXINIT.
4585 */
32874aea 4586static int in_commasep_string(char *needle, char *haystack, int haylen)
4587{
57356d63 4588 int needlen;
4589 if (!needle || !haystack) /* protect against null pointers */
4590 return 0;
4591 needlen = strlen(needle);
e5574168 4592 while (1) {
32874aea 4593 /*
4594 * Is it at the start of the string?
4595 */
4596 if (haylen >= needlen && /* haystack is long enough */
4597 !memcmp(needle, haystack, needlen) && /* initial match */
4598 (haylen == needlen || haystack[needlen] == ',')
4599 /* either , or EOS follows */
4600 )
4601 return 1;
4602 /*
4603 * If not, search for the next comma and resume after that.
4604 * If no comma found, terminate.
4605 */
4606 while (haylen > 0 && *haystack != ',')
4607 haylen--, haystack++;
4608 if (haylen == 0)
4609 return 0;
4610 haylen--, haystack++; /* skip over comma itself */
e5574168 4611 }
4612}
4613
4614/*
d39f364a 4615 * SSH2 key creation method.
4616 */
d8baa528 4617static void ssh2_mkkey(Ssh ssh, Bignum K, unsigned char *H,
4618 unsigned char *sessid, char chr,
4619 unsigned char *keyspace)
32874aea 4620{
d39f364a 4621 SHA_State s;
4622 /* First 20 bytes. */
4623 SHA_Init(&s);
51470298 4624 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
088bde77 4625 sha_mpint(&s, K);
d39f364a 4626 SHA_Bytes(&s, H, 20);
4627 SHA_Bytes(&s, &chr, 1);
5e0d7cb8 4628 SHA_Bytes(&s, sessid, 20);
d39f364a 4629 SHA_Final(&s, keyspace);
4630 /* Next 20 bytes. */
4631 SHA_Init(&s);
51470298 4632 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
088bde77 4633 sha_mpint(&s, K);
d39f364a 4634 SHA_Bytes(&s, H, 20);
4635 SHA_Bytes(&s, keyspace, 20);
32874aea 4636 SHA_Final(&s, keyspace + 20);
d39f364a 4637}
4638
4639/*
7cca0d81 4640 * Handle the SSH2 transport layer.
e5574168 4641 */
ff3187f6 4642static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen,
4643 struct Packet *pktin)
e5574168 4644{
51470298 4645 struct do_ssh2_transport_state {
4646 int nbits, pbits, warn;
4647 Bignum p, g, e, f, K;
4648 int kex_init_value, kex_reply_value;
4649 const struct ssh_mac **maclist;
4650 int nmacs;
4651 const struct ssh2_cipher *cscipher_tobe;
4652 const struct ssh2_cipher *sccipher_tobe;
4653 const struct ssh_mac *csmac_tobe;
4654 const struct ssh_mac *scmac_tobe;
4655 const struct ssh_compress *cscomp_tobe;
4656 const struct ssh_compress *sccomp_tobe;
4657 char *hostkeydata, *sigdata, *keystr, *fingerprint;
4658 int hostkeylen, siglen;
4659 void *hkey; /* actual host key */
4660 unsigned char exchange_hash[20];
83e7d008 4661 int n_preferred_kex;
4662 const struct ssh_kex *preferred_kex[KEX_MAX];
51470298 4663 int n_preferred_ciphers;
4664 const struct ssh2_ciphers *preferred_ciphers[CIPHER_MAX];
4665 const struct ssh_compress *preferred_comp;
e13bba36 4666 int got_session_id, activated_authconn;
ff3187f6 4667 struct Packet *pktout;
51470298 4668 };
4669 crState(do_ssh2_transport_state);
4670
4671 crBegin(ssh->do_ssh2_transport_crstate);
4672
4673 s->cscipher_tobe = s->sccipher_tobe = NULL;
4674 s->csmac_tobe = s->scmac_tobe = NULL;
4675 s->cscomp_tobe = s->sccomp_tobe = NULL;
4676
e13bba36 4677 s->got_session_id = s->activated_authconn = FALSE;
e5574168 4678
e13bba36 4679 /*
4680 * Be prepared to work around the buggy MAC problem.
4681 */
4682 if (ssh->remote_bugs & BUG_SSH2_HMAC)
4683 s->maclist = buggymacs, s->nmacs = lenof(buggymacs);
4684 else
4685 s->maclist = macs, s->nmacs = lenof(macs);
4686
4687 begin_key_exchange:
149d2abc 4688 ssh->pkt_ctx &= ~SSH2_PKTCTX_KEX_MASK;
51470298 4689 {
e13bba36 4690 int i, j, commalist_started;
4691
51470298 4692 /*
83e7d008 4693 * Set up the preferred key exchange. (NULL => warn below here)
4694 */
4695 s->n_preferred_kex = 0;
4696 for (i = 0; i < KEX_MAX; i++) {
4697 switch (ssh->cfg.ssh_kexlist[i]) {
4698 case KEX_DHGEX:
4699 s->preferred_kex[s->n_preferred_kex++] =
4700 &ssh_diffiehellman_gex;
4701 break;
4702 case KEX_DHGROUP14:
4703 s->preferred_kex[s->n_preferred_kex++] =
4704 &ssh_diffiehellman_group14;
4705 break;
4706 case KEX_DHGROUP1:
4707 s->preferred_kex[s->n_preferred_kex++] =
4708 &ssh_diffiehellman_group1;
4709 break;
4710 case CIPHER_WARN:
4711 /* Flag for later. Don't bother if it's the last in
4712 * the list. */
4713 if (i < KEX_MAX - 1) {
4714 s->preferred_kex[s->n_preferred_kex++] = NULL;
4715 }
4716 break;
4717 }
4718 }
83e7d008 4719
83e7d008 4720 /*
51470298 4721 * Set up the preferred ciphers. (NULL => warn below here)
4722 */
4723 s->n_preferred_ciphers = 0;
4724 for (i = 0; i < CIPHER_MAX; i++) {
86916870 4725 switch (ssh->cfg.ssh_cipherlist[i]) {
51470298 4726 case CIPHER_BLOWFISH:
4727 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_blowfish;
4728 break;
4729 case CIPHER_DES:
86916870 4730 if (ssh->cfg.ssh2_des_cbc) {
51470298 4731 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_des;
4732 }
4733 break;
4734 case CIPHER_3DES:
4735 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_3des;
4736 break;
4737 case CIPHER_AES:
4738 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_aes;
4739 break;
4740 case CIPHER_WARN:
4741 /* Flag for later. Don't bother if it's the last in
4742 * the list. */
4743 if (i < CIPHER_MAX - 1) {
4744 s->preferred_ciphers[s->n_preferred_ciphers++] = NULL;
4745 }
4746 break;
ca20bfcf 4747 }
ca20bfcf 4748 }
7591b9ff 4749
e13bba36 4750 /*
4751 * Set up preferred compression.
4752 */
4753 if (ssh->cfg.compression)
4754 s->preferred_comp = &ssh_zlib;
4755 else
4756 s->preferred_comp = &ssh_comp_none;
51470298 4757
4758 /*
590f6a5f 4759 * Enable queueing of outgoing auth- or connection-layer
4760 * packets while we are in the middle of a key exchange.
4761 */
4762 ssh->queueing = TRUE;
4763
4764 /*
9442dd57 4765 * Flag that KEX is in progress.
4766 */
4767 ssh->kex_in_progress = TRUE;
4768
4769 /*
51470298 4770 * Construct and send our key exchange packet.
4771 */
ff3187f6 4772 s->pktout = ssh2_pkt_init(SSH2_MSG_KEXINIT);
51470298 4773 for (i = 0; i < 16; i++)
ff3187f6 4774 ssh2_pkt_addbyte(s->pktout, (unsigned char) random_byte());
51470298 4775 /* List key exchange algorithms. */
ff3187f6 4776 ssh2_pkt_addstring_start(s->pktout);
83e7d008 4777 commalist_started = 0;
4778 for (i = 0; i < s->n_preferred_kex; i++) {
4779 const struct ssh_kex *k = s->preferred_kex[i];
4780 if (!k) continue; /* warning flag */
4781 if (commalist_started)
ff3187f6 4782 ssh2_pkt_addstring_str(s->pktout, ",");
83e7d008 4783 ssh2_pkt_addstring_str(s->pktout, s->preferred_kex[i]->name);
4784 commalist_started = 1;
32874aea 4785 }
51470298 4786 /* List server host key algorithms. */
ff3187f6 4787 ssh2_pkt_addstring_start(s->pktout);
51470298 4788 for (i = 0; i < lenof(hostkey_algs); i++) {
ff3187f6 4789 ssh2_pkt_addstring_str(s->pktout, hostkey_algs[i]->name);
51470298 4790 if (i < lenof(hostkey_algs) - 1)
ff3187f6 4791 ssh2_pkt_addstring_str(s->pktout, ",");
32874aea 4792 }
51470298 4793 /* List client->server encryption algorithms. */
ff3187f6 4794 ssh2_pkt_addstring_start(s->pktout);
83e7d008 4795 commalist_started = 0;
51470298 4796 for (i = 0; i < s->n_preferred_ciphers; i++) {
4797 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4798 if (!c) continue; /* warning flag */
4799 for (j = 0; j < c->nciphers; j++) {
83e7d008 4800 if (commalist_started)
ff3187f6 4801 ssh2_pkt_addstring_str(s->pktout, ",");
4802 ssh2_pkt_addstring_str(s->pktout, c->list[j]->name);
83e7d008 4803 commalist_started = 1;
51470298 4804 }
4805 }
4806 /* List server->client encryption algorithms. */
ff3187f6 4807 ssh2_pkt_addstring_start(s->pktout);
83e7d008 4808 commalist_started = 0;
51470298 4809 for (i = 0; i < s->n_preferred_ciphers; i++) {
4810 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4811 if (!c) continue; /* warning flag */
4812 for (j = 0; j < c->nciphers; j++) {
83e7d008 4813 if (commalist_started)
ff3187f6 4814 ssh2_pkt_addstring_str(s->pktout, ",");
4815 ssh2_pkt_addstring_str(s->pktout, c->list[j]->name);
83e7d008 4816 commalist_started = 1;
51470298 4817 }
4818 }
4819 /* List client->server MAC algorithms. */
ff3187f6 4820 ssh2_pkt_addstring_start(s->pktout);
51470298 4821 for (i = 0; i < s->nmacs; i++) {
ff3187f6 4822 ssh2_pkt_addstring_str(s->pktout, s->maclist[i]->name);
51470298 4823 if (i < s->nmacs - 1)
ff3187f6 4824 ssh2_pkt_addstring_str(s->pktout, ",");
51470298 4825 }
4826 /* List server->client MAC algorithms. */
ff3187f6 4827 ssh2_pkt_addstring_start(s->pktout);
51470298 4828 for (i = 0; i < s->nmacs; i++) {
ff3187f6 4829 ssh2_pkt_addstring_str(s->pktout, s->maclist[i]->name);
51470298 4830 if (i < s->nmacs - 1)
ff3187f6 4831 ssh2_pkt_addstring_str(s->pktout, ",");
51470298 4832 }
4833 /* List client->server compression algorithms. */
ff3187f6 4834 ssh2_pkt_addstring_start(s->pktout);
f6e0abe2 4835 assert(lenof(compressions) > 1);
ff3187f6 4836 ssh2_pkt_addstring_str(s->pktout, s->preferred_comp->name);
f6e0abe2 4837 for (i = 0; i < lenof(compressions); i++) {
4838 const struct ssh_compress *c = compressions[i];
4839 if (c != s->preferred_comp) {
ff3187f6 4840 ssh2_pkt_addstring_str(s->pktout, ",");
4841 ssh2_pkt_addstring_str(s->pktout, c->name);
f6e0abe2 4842 }
51470298 4843 }
4844 /* List server->client compression algorithms. */
ff3187f6 4845 ssh2_pkt_addstring_start(s->pktout);
f6e0abe2 4846 assert(lenof(compressions) > 1);
ff3187f6 4847 ssh2_pkt_addstring_str(s->pktout, s->preferred_comp->name);
f6e0abe2 4848 for (i = 0; i < lenof(compressions); i++) {
4849 const struct ssh_compress *c = compressions[i];
4850 if (c != s->preferred_comp) {
ff3187f6 4851 ssh2_pkt_addstring_str(s->pktout, ",");
4852 ssh2_pkt_addstring_str(s->pktout, c->name);
f6e0abe2 4853 }
51470298 4854 }
4855 /* List client->server languages. Empty list. */
ff3187f6 4856 ssh2_pkt_addstring_start(s->pktout);
51470298 4857 /* List server->client languages. Empty list. */
ff3187f6 4858 ssh2_pkt_addstring_start(s->pktout);
51470298 4859 /* First KEX packet does _not_ follow, because we're not that brave. */
ff3187f6 4860 ssh2_pkt_addbool(s->pktout, FALSE);
51470298 4861 /* Reserved. */
ff3187f6 4862 ssh2_pkt_adduint32(s->pktout, 0);
e5574168 4863 }
0db56f73 4864
51470298 4865 ssh->exhash = ssh->exhashbase;
ff3187f6 4866 sha_string(&ssh->exhash, s->pktout->data + 5, s->pktout->length - 5);
0db56f73 4867
590f6a5f 4868 ssh2_pkt_send_noqueue(ssh, s->pktout);
e5574168 4869
ff3187f6 4870 if (!pktin)
4871 crWaitUntil(pktin);
4872 if (pktin->length > 5)
4873 sha_string(&ssh->exhash, pktin->data + 5, pktin->length - 5);
e5574168 4874
4875 /*
4876 * Now examine the other side's KEXINIT to see what we're up
4877 * to.
4878 */
51470298 4879 {
4880 char *str;
4881 int i, j, len;
4882
ff3187f6 4883 if (pktin->type != SSH2_MSG_KEXINIT) {
6b5cf8b4 4884 bombout(("expected key exchange packet from server"));
7ffdbc1a 4885 crStop(0);
32874aea 4886 }
51470298 4887 ssh->kex = NULL;
4888 ssh->hostkey = NULL;
4889 s->cscipher_tobe = NULL;
4890 s->sccipher_tobe = NULL;
4891 s->csmac_tobe = NULL;
4892 s->scmac_tobe = NULL;
4893 s->cscomp_tobe = NULL;
4894 s->sccomp_tobe = NULL;
ff3187f6 4895 pktin->savedpos += 16; /* skip garbage cookie */
4896 ssh_pkt_getstring(pktin, &str, &len); /* key exchange algorithms */
83e7d008 4897 s->warn = 0;
4898 for (i = 0; i < s->n_preferred_kex; i++) {
4899 const struct ssh_kex *k = s->preferred_kex[i];
4900 if (!k) {
4901 s->warn = 1;
4902 } else if (in_commasep_string(k->name, str, len)) {
4903 ssh->kex = k;
4904 }
4905 if (ssh->kex) {
bb348ab1 4906 if (s->warn) {
4907 sk_set_frozen(ssh->s, 1);
83e7d008 4908 askalg(ssh->frontend, "key-exchange algorithm",
4909 ssh->kex->name);
bb348ab1 4910 sk_set_frozen(ssh->s, 0);
4911 }
51470298 4912 break;
4913 }
32874aea 4914 }
83e7d008 4915 if (!ssh->kex) {
4916 bombout(("Couldn't agree a key exchange algorithm (available: %s)",
4917 str ? str : "(null)"));
4918 crStop(0);
4919 }
ff3187f6 4920 ssh_pkt_getstring(pktin, &str, &len); /* host key algorithms */
51470298 4921 for (i = 0; i < lenof(hostkey_algs); i++) {
4922 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
4923 ssh->hostkey = hostkey_algs[i];
4924 break;
4925 }
4926 }
ff3187f6 4927 ssh_pkt_getstring(pktin, &str, &len); /* client->server cipher */
51470298 4928 s->warn = 0;
4929 for (i = 0; i < s->n_preferred_ciphers; i++) {
4930 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4931 if (!c) {
4932 s->warn = 1;
4933 } else {
4934 for (j = 0; j < c->nciphers; j++) {
4935 if (in_commasep_string(c->list[j]->name, str, len)) {
4936 s->cscipher_tobe = c->list[j];
4937 break;
4938 }
ca20bfcf 4939 }
32874aea 4940 }
51470298 4941 if (s->cscipher_tobe) {
bb348ab1 4942 if (s->warn) {
4943 sk_set_frozen(ssh->s, 1);
83e7d008 4944 askalg(ssh->frontend, "client-to-server cipher",
4945 s->cscipher_tobe->name);
bb348ab1 4946 sk_set_frozen(ssh->s, 0);
4947 }
51470298 4948 break;
4949 }
32874aea 4950 }
51470298 4951 if (!s->cscipher_tobe) {
6b5cf8b4 4952 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
57356d63 4953 str ? str : "(null)"));
7ffdbc1a 4954 crStop(0);
ca20bfcf 4955 }
0ef8f407 4956
ff3187f6 4957 ssh_pkt_getstring(pktin, &str, &len); /* server->client cipher */
51470298 4958 s->warn = 0;
4959 for (i = 0; i < s->n_preferred_ciphers; i++) {
4960 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4961 if (!c) {
4962 s->warn = 1;
4963 } else {
4964 for (j = 0; j < c->nciphers; j++) {
4965 if (in_commasep_string(c->list[j]->name, str, len)) {
4966 s->sccipher_tobe = c->list[j];
4967 break;
4968 }
ca20bfcf 4969 }
32874aea 4970 }
51470298 4971 if (s->sccipher_tobe) {
bb348ab1 4972 if (s->warn) {
4973 sk_set_frozen(ssh->s, 1);
83e7d008 4974 askalg(ssh->frontend, "server-to-client cipher",
4975 s->sccipher_tobe->name);
bb348ab1 4976 sk_set_frozen(ssh->s, 0);
4977 }
51470298 4978 break;
4979 }
32874aea 4980 }
51470298 4981 if (!s->sccipher_tobe) {
6b5cf8b4 4982 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
57356d63 4983 str ? str : "(null)"));
7ffdbc1a 4984 crStop(0);
ca20bfcf 4985 }
0ef8f407 4986
ff3187f6 4987 ssh_pkt_getstring(pktin, &str, &len); /* client->server mac */
51470298 4988 for (i = 0; i < s->nmacs; i++) {
4989 if (in_commasep_string(s->maclist[i]->name, str, len)) {
4990 s->csmac_tobe = s->maclist[i];
4991 break;
4992 }
32874aea 4993 }
ff3187f6 4994 ssh_pkt_getstring(pktin, &str, &len); /* server->client mac */
51470298 4995 for (i = 0; i < s->nmacs; i++) {
4996 if (in_commasep_string(s->maclist[i]->name, str, len)) {
4997 s->scmac_tobe = s->maclist[i];
4998 break;
4999 }
32874aea 5000 }
ff3187f6 5001 ssh_pkt_getstring(pktin, &str, &len); /* client->server compression */
51470298 5002 for (i = 0; i < lenof(compressions) + 1; i++) {
5003 const struct ssh_compress *c =
5004 i == 0 ? s->preferred_comp : compressions[i - 1];
5005 if (in_commasep_string(c->name, str, len)) {
5006 s->cscomp_tobe = c;
5007 break;
5008 }
32874aea 5009 }
ff3187f6 5010 ssh_pkt_getstring(pktin, &str, &len); /* server->client compression */
51470298 5011 for (i = 0; i < lenof(compressions) + 1; i++) {
5012 const struct ssh_compress *c =
5013 i == 0 ? s->preferred_comp : compressions[i - 1];
5014 if (in_commasep_string(c->name, str, len)) {
5015 s->sccomp_tobe = c;
5016 break;
5017 }
32874aea 5018 }
e5574168 5019 }
e5574168 5020
5021 /*
7bd5a860 5022 * Work out the number of bits of key we will need from the key
5023 * exchange. We start with the maximum key length of either
5024 * cipher...
5025 */
5026 {
32874aea 5027 int csbits, scbits;
7bd5a860 5028
51470298 5029 csbits = s->cscipher_tobe->keylen;
5030 scbits = s->sccipher_tobe->keylen;
5031 s->nbits = (csbits > scbits ? csbits : scbits);
7bd5a860 5032 }
5033 /* The keys only have 160-bit entropy, since they're based on
5034 * a SHA-1 hash. So cap the key size at 160 bits. */
51470298 5035 if (s->nbits > 160)
5036 s->nbits = 160;
7bd5a860 5037
5038 /*
a92dd380 5039 * If we're doing Diffie-Hellman group exchange, start by
5040 * requesting a group.
e5574168 5041 */
d1aaf71d 5042 if (!ssh->kex->pdata) {
32874aea 5043 logevent("Doing Diffie-Hellman group exchange");
51470298 5044 ssh->pkt_ctx |= SSH2_PKTCTX_DHGEX;
32874aea 5045 /*
5046 * Work out how big a DH group we will need to allow that
5047 * much data.
7bd5a860 5048 */
51470298 5049 s->pbits = 512 << ((s->nbits - 1) / 64);
ff3187f6 5050 s->pktout = ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST);
5051 ssh2_pkt_adduint32(s->pktout, s->pbits);
590f6a5f 5052 ssh2_pkt_send_noqueue(ssh, s->pktout);
32874aea 5053
ff3187f6 5054 crWaitUntil(pktin);
5055 if (pktin->type != SSH2_MSG_KEX_DH_GEX_GROUP) {
6b5cf8b4 5056 bombout(("expected key exchange group packet from server"));
7ffdbc1a 5057 crStop(0);
32874aea 5058 }
ff3187f6 5059 s->p = ssh2_pkt_getmp(pktin);
5060 s->g = ssh2_pkt_getmp(pktin);
5061 if (!s->p || !s->g) {
5062 bombout(("unable to read mp-ints from incoming group packet"));
5063 crStop(0);
5064 }
d1aaf71d 5065 ssh->kex_ctx = dh_setup_gex(s->p, s->g);
51470298 5066 s->kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
5067 s->kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY;
a92dd380 5068 } else {
d1aaf71d 5069 ssh->pkt_ctx |= SSH2_PKTCTX_DHGROUP;
5070 ssh->kex_ctx = dh_setup_group(ssh->kex);
51470298 5071 s->kex_init_value = SSH2_MSG_KEXDH_INIT;
5072 s->kex_reply_value = SSH2_MSG_KEXDH_REPLY;
d1aaf71d 5073 logeventf(ssh, "Using Diffie-Hellman with standard group \"%s\"",
5074 ssh->kex->groupname);
8d5de777 5075 }
e5574168 5076
a92dd380 5077 logevent("Doing Diffie-Hellman key exchange");
e5574168 5078 /*
a92dd380 5079 * Now generate and send e for Diffie-Hellman.
e5574168 5080 */
27cd7fc2 5081 s->e = dh_create_e(ssh->kex_ctx, s->nbits * 2);
ff3187f6 5082 s->pktout = ssh2_pkt_init(s->kex_init_value);
5083 ssh2_pkt_addmp(s->pktout, s->e);
590f6a5f 5084 ssh2_pkt_send_noqueue(ssh, s->pktout);
e5574168 5085
ff3187f6 5086 crWaitUntil(pktin);
5087 if (pktin->type != s->kex_reply_value) {
6b5cf8b4 5088 bombout(("expected key exchange reply packet from server"));
7ffdbc1a 5089 crStop(0);
7cca0d81 5090 }
ff3187f6 5091 ssh_pkt_getstring(pktin, &s->hostkeydata, &s->hostkeylen);
5092 s->f = ssh2_pkt_getmp(pktin);
5093 if (!s->f) {
5094 bombout(("unable to parse key exchange reply packet"));
5095 crStop(0);
5096 }
5097 ssh_pkt_getstring(pktin, &s->sigdata, &s->siglen);
e5574168 5098
27cd7fc2 5099 s->K = dh_find_K(ssh->kex_ctx, s->f);
e5574168 5100
51470298 5101 sha_string(&ssh->exhash, s->hostkeydata, s->hostkeylen);
5102 if (ssh->kex == &ssh_diffiehellman_gex) {
5103 sha_uint32(&ssh->exhash, s->pbits);
5104 sha_mpint(&ssh->exhash, s->p);
5105 sha_mpint(&ssh->exhash, s->g);
a92dd380 5106 }
51470298 5107 sha_mpint(&ssh->exhash, s->e);
5108 sha_mpint(&ssh->exhash, s->f);
5109 sha_mpint(&ssh->exhash, s->K);
5110 SHA_Final(&ssh->exhash, s->exchange_hash);
e5574168 5111
27cd7fc2 5112 dh_cleanup(ssh->kex_ctx);
fabd1805 5113 ssh->kex_ctx = NULL;
3709bfe9 5114
7cca0d81 5115#if 0
765c4200 5116 debug(("Exchange hash is:\n"));
51470298 5117 dmemdump(s->exchange_hash, 20);
7cca0d81 5118#endif
5119
51470298 5120 s->hkey = ssh->hostkey->newkey(s->hostkeydata, s->hostkeylen);
5121 if (!s->hkey ||
5122 !ssh->hostkey->verifysig(s->hkey, s->sigdata, s->siglen,
d8baa528 5123 (char *)s->exchange_hash, 20)) {
6b5cf8b4 5124 bombout(("Server's host key did not match the signature supplied"));
7ffdbc1a 5125 crStop(0);
8d5de777 5126 }
e5574168 5127
5128 /*
7cca0d81 5129 * Authenticate remote host: verify host key. (We've already
5130 * checked the signature of the exchange hash.)
e5574168 5131 */
51470298 5132 s->keystr = ssh->hostkey->fmtkey(s->hkey);
5133 s->fingerprint = ssh->hostkey->fingerprint(s->hkey);
bb348ab1 5134 sk_set_frozen(ssh->s, 1);
a8327734 5135 verify_ssh_host_key(ssh->frontend,
5136 ssh->savedhost, ssh->savedport, ssh->hostkey->keytype,
51470298 5137 s->keystr, s->fingerprint);
bb348ab1 5138 sk_set_frozen(ssh->s, 0);
e13bba36 5139 if (!s->got_session_id) { /* don't bother logging this in rekeys */
5e0d7cb8 5140 logevent("Host key fingerprint is:");
51470298 5141 logevent(s->fingerprint);
5e0d7cb8 5142 }
51470298 5143 sfree(s->fingerprint);
5144 sfree(s->keystr);
5145 ssh->hostkey->freekey(s->hkey);
d39f364a 5146
5147 /*
9442dd57 5148 * The exchange hash from the very first key exchange is also
5149 * the session id, used in session key construction and
5150 * authentication.
5151 */
e13bba36 5152 if (!s->got_session_id) {
9442dd57 5153 memcpy(ssh->v2_session_id, s->exchange_hash,
5154 sizeof(s->exchange_hash));
e13bba36 5155 s->got_session_id = TRUE;
5156 }
9442dd57 5157
5158 /*
7cca0d81 5159 * Send SSH2_MSG_NEWKEYS.
d39f364a 5160 */
ff3187f6 5161 s->pktout = ssh2_pkt_init(SSH2_MSG_NEWKEYS);
590f6a5f 5162 ssh2_pkt_send_noqueue(ssh, s->pktout);
9442dd57 5163 ssh->outgoing_data_size = 0; /* start counting from here */
5164
5165 /*
5166 * We've sent client NEWKEYS, so create and initialise
c64fe7d4 5167 * client-to-server session keys.
9442dd57 5168 */
5169 if (ssh->cs_cipher_ctx)
5170 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
5171 ssh->cscipher = s->cscipher_tobe;
5172 ssh->cs_cipher_ctx = ssh->cscipher->make_context();
5173
5174 if (ssh->cs_mac_ctx)
5175 ssh->csmac->free_context(ssh->cs_mac_ctx);
5176 ssh->csmac = s->csmac_tobe;
5177 ssh->cs_mac_ctx = ssh->csmac->make_context();
5178
5179 if (ssh->cs_comp_ctx)
5180 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
5181 ssh->cscomp = s->cscomp_tobe;
5182 ssh->cs_comp_ctx = ssh->cscomp->compress_init();
5183
5184 /*
5185 * Set IVs on client-to-server keys. Here we use the exchange
5186 * hash from the _first_ key exchange.
5187 */
5188 {
5189 unsigned char keyspace[40];
5190 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'C',keyspace);
5191 ssh->cscipher->setkey(ssh->cs_cipher_ctx, keyspace);
5192 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'A',keyspace);
5193 ssh->cscipher->setiv(ssh->cs_cipher_ctx, keyspace);
5194 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'E',keyspace);
5195 ssh->csmac->setkey(ssh->cs_mac_ctx, keyspace);
5196 }
5197
5198 logeventf(ssh, "Initialised %.200s client->server encryption",
5199 ssh->cscipher->text_name);
5200 logeventf(ssh, "Initialised %.200s client->server MAC algorithm",
5201 ssh->csmac->text_name);
5202 if (ssh->cscomp->text_name)
5203 logeventf(ssh, "Initialised %s compression",
5204 ssh->cscomp->text_name);
590f6a5f 5205
5206 /*
5207 * Now our end of the key exchange is complete, we can send all
5208 * our queued higher-layer packets.
5209 */
5210 ssh->queueing = FALSE;
5211 ssh2_pkt_queuesend(ssh);
d39f364a 5212
5213 /*
8406eaf9 5214 * Expect SSH2_MSG_NEWKEYS from server.
5215 */
ff3187f6 5216 crWaitUntil(pktin);
5217 if (pktin->type != SSH2_MSG_NEWKEYS) {
6b5cf8b4 5218 bombout(("expected new-keys packet from server"));
7ffdbc1a 5219 crStop(0);
8406eaf9 5220 }
9442dd57 5221 ssh->incoming_data_size = 0; /* start counting from here */
8406eaf9 5222
5223 /*
9442dd57 5224 * We've seen server NEWKEYS, so create and initialise
5225 * server-to-client session keys.
d39f364a 5226 */
371e569c 5227 if (ssh->sc_cipher_ctx)
5228 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
51470298 5229 ssh->sccipher = s->sccipher_tobe;
371e569c 5230 ssh->sc_cipher_ctx = ssh->sccipher->make_context();
e0e1a00d 5231
e0e1a00d 5232 if (ssh->sc_mac_ctx)
5233 ssh->scmac->free_context(ssh->sc_mac_ctx);
51470298 5234 ssh->scmac = s->scmac_tobe;
e0e1a00d 5235 ssh->sc_mac_ctx = ssh->scmac->make_context();
5236
5366aed8 5237 if (ssh->sc_comp_ctx)
5238 ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
51470298 5239 ssh->sccomp = s->sccomp_tobe;
5366aed8 5240 ssh->sc_comp_ctx = ssh->sccomp->decompress_init();
5241
d39f364a 5242 /*
9442dd57 5243 * Set IVs on server-to-client keys. Here we use the exchange
5244 * hash from the _first_ key exchange.
d39f364a 5245 */
51470298 5246 {
5247 unsigned char keyspace[40];
51470298 5248 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'D',keyspace);
371e569c 5249 ssh->sccipher->setkey(ssh->sc_cipher_ctx, keyspace);
51470298 5250 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'B',keyspace);
371e569c 5251 ssh->sccipher->setiv(ssh->sc_cipher_ctx, keyspace);
51470298 5252 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'F',keyspace);
e0e1a00d 5253 ssh->scmac->setkey(ssh->sc_mac_ctx, keyspace);
51470298 5254 }
57356d63 5255 logeventf(ssh, "Initialised %.200s server->client encryption",
5256 ssh->sccipher->text_name);
6c135243 5257 logeventf(ssh, "Initialised %.200s server->client MAC algorithm",
5258 ssh->scmac->text_name);
57356d63 5259 if (ssh->sccomp->text_name)
5260 logeventf(ssh, "Initialised %s decompression",
5261 ssh->sccomp->text_name);
9442dd57 5262
5263 /*
5264 * Free key exchange data.
5265 */
679539d7 5266 freebn(s->f);
679539d7 5267 freebn(s->K);
b3949e7e 5268 if (ssh->kex == &ssh_diffiehellman_gex) {
5269 freebn(s->g);
5270 freebn(s->p);
5271 }
d39f364a 5272
033b4cef 5273 /*
e13bba36 5274 * Key exchange is over. Loop straight back round if we have a
5275 * deferred rekey reason.
5276 */
5277 if (ssh->deferred_rekey_reason) {
5278 logevent(ssh->deferred_rekey_reason);
5279 pktin = NULL;
5280 ssh->deferred_rekey_reason = NULL;
5281 goto begin_key_exchange;
5282 }
5283
5284 /*
5285 * Otherwise, schedule a timer for our next rekey.
9442dd57 5286 */
5287 ssh->kex_in_progress = FALSE;
e6c1536e 5288 ssh->last_rekey = GETTICKCOUNT();
d57f70af 5289 if (ssh->cfg.ssh_rekey_time != 0)
5290 ssh->next_rekey = schedule_timer(ssh->cfg.ssh_rekey_time*60*TICKSPERSEC,
5291 ssh2_timer, ssh);
e13bba36 5292
9442dd57 5293 /*
0db56f73 5294 * If this is the first key exchange phase, we must pass the
5295 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
5296 * wants to see it but because it will need time to initialise
5297 * itself before it sees an actual packet. In subsequent key
5298 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
5299 * it would only confuse the layer above.
5300 */
e13bba36 5301 if (s->activated_authconn) {
b09eaa88 5302 crReturn(1);
0db56f73 5303 }
e13bba36 5304 s->activated_authconn = TRUE;
0db56f73 5305
5306 /*
7cca0d81 5307 * Now we're encrypting. Begin returning 1 to the protocol main
5308 * function so that other things can run on top of the
5309 * transport. If we ever see a KEXINIT, we must go back to the
5310 * start.
9442dd57 5311 *
5312 * We _also_ go back to the start if we see pktin==NULL and
5313 * inlen==-1, because this is a special signal meaning
5314 * `initiate client-driven rekey', and `in' contains a message
5315 * giving the reason for the rekey.
033b4cef 5316 */
9442dd57 5317 while (!((pktin && pktin->type == SSH2_MSG_KEXINIT) ||
5318 (!pktin && inlen == -1))) {
f382c87d 5319 wait_for_rekey:
32874aea 5320 crReturn(1);
e96adf72 5321 }
9442dd57 5322 if (pktin) {
5323 logevent("Server initiated key re-exchange");
5324 } else {
f382c87d 5325 /*
5326 * Special case: if the server bug is set that doesn't
5327 * allow rekeying, we give a different log message and
5328 * continue waiting. (If such a server _initiates_ a rekey,
5329 * we process it anyway!)
5330 */
5331 if ((ssh->remote_bugs & BUG_SSH2_REKEY)) {
5332 logeventf(ssh, "Server bug prevents key re-exchange (%s)",
5333 (char *)in);
5334 /* Reset the counters, so that at least this message doesn't
5335 * hit the event log _too_ often. */
5336 ssh->outgoing_data_size = 0;
5337 ssh->incoming_data_size = 0;
5338 if (ssh->cfg.ssh_rekey_time != 0) {
5339 ssh->next_rekey =
5340 schedule_timer(ssh->cfg.ssh_rekey_time*60*TICKSPERSEC,
5341 ssh2_timer, ssh);
5342 }
5343 goto wait_for_rekey; /* this is utterly horrid */
5344 } else {
5345 logeventf(ssh, "Initiating key re-exchange (%s)", (char *)in);
f382c87d 5346 }
9442dd57 5347 }
7cca0d81 5348 goto begin_key_exchange;
e5574168 5349
5350 crFinish(1);
5351}
5352
7cca0d81 5353/*
783415f8 5354 * Add data to an SSH2 channel output buffer.
5355 */
32874aea 5356static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
5357 int len)
5358{
5471d09a 5359 bufchain_add(&c->v.v2.outbuffer, buf, len);
783415f8 5360}
5361
5362/*
5363 * Attempt to send data on an SSH2 channel.
5364 */
5471d09a 5365static int ssh2_try_send(struct ssh_channel *c)
32874aea 5366{
51470298 5367 Ssh ssh = c->ssh;
ff3187f6 5368 struct Packet *pktout;
51470298 5369
5471d09a 5370 while (c->v.v2.remwindow > 0 && bufchain_size(&c->v.v2.outbuffer) > 0) {
5371 int len;
5372 void *data;
5373 bufchain_prefix(&c->v.v2.outbuffer, &data, &len);
5374 if ((unsigned)len > c->v.v2.remwindow)
5375 len = c->v.v2.remwindow;
5376 if ((unsigned)len > c->v.v2.remmaxpkt)
5377 len = c->v.v2.remmaxpkt;
ff3187f6 5378 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
5379 ssh2_pkt_adduint32(pktout, c->remoteid);
5380 dont_log_data(ssh, pktout, PKTLOG_OMIT);
5381 ssh2_pkt_addstring_start(pktout);
5382 ssh2_pkt_addstring_data(pktout, data, len);
5383 end_log_omission(ssh, pktout);
5384 ssh2_pkt_send(ssh, pktout);
5471d09a 5385 bufchain_consume(&c->v.v2.outbuffer, len);
5386 c->v.v2.remwindow -= len;
5387 }
5388
5389 /*
5390 * After having sent as much data as we can, return the amount
5391 * still buffered.
5392 */
5393 return bufchain_size(&c->v.v2.outbuffer);
5394}
5395
5396/*
5397 * Potentially enlarge the window on an SSH2 channel.
5398 */
5399static void ssh2_set_window(struct ssh_channel *c, unsigned newwin)
5400{
51470298 5401 Ssh ssh = c->ssh;
5402
6b69f42e 5403 /*
5404 * Never send WINDOW_ADJUST for a channel that the remote side
5405 * already thinks it's closed; there's no point, since it won't
5406 * be sending any more data anyway.
5407 */
5408 if (c->closes != 0)
5409 return;
5410
5471d09a 5411 if (newwin > c->v.v2.locwindow) {
ff3187f6 5412 struct Packet *pktout;
5413
5414 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
5415 ssh2_pkt_adduint32(pktout, c->remoteid);
5416 ssh2_pkt_adduint32(pktout, newwin - c->v.v2.locwindow);
5417 ssh2_pkt_send(ssh, pktout);
5471d09a 5418 c->v.v2.locwindow = newwin;
783415f8 5419 }
5420}
5421
51df0ab5 5422static void ssh2_msg_channel_window_adjust(Ssh ssh, struct Packet *pktin)
b09eaa88 5423{
5424 unsigned i = ssh_pkt_getuint32(pktin);
5425 struct ssh_channel *c;
5426 c = find234(ssh->channels, &i, ssh_channelfind);
5427 if (c && !c->closes)
5428 c->v.v2.remwindow += ssh_pkt_getuint32(pktin);
5429}
5430
51df0ab5 5431static void ssh2_msg_channel_data(Ssh ssh, struct Packet *pktin)
5432{
5433 char *data;
aa63ab7e 5434 unsigned int length;
51df0ab5 5435 unsigned i = ssh_pkt_getuint32(pktin);
5436 struct ssh_channel *c;
5437 c = find234(ssh->channels, &i, ssh_channelfind);
5438 if (!c)
5439 return; /* nonexistent channel */
5440 if (pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
5441 ssh_pkt_getuint32(pktin) != SSH2_EXTENDED_DATA_STDERR)
5442 return; /* extended but not stderr */
5443 ssh_pkt_getstring(pktin, &data, &length);
5444 if (data) {
5445 int bufsize = 0;
5446 c->v.v2.locwindow -= length;
5447 switch (c->type) {
5448 case CHAN_MAINSESSION:
5449 bufsize =
5450 from_backend(ssh->frontend, pktin->type ==
5451 SSH2_MSG_CHANNEL_EXTENDED_DATA,
5452 data, length);
5453 break;
5454 case CHAN_X11:
5455 bufsize = x11_send(c->u.x11.s, data, length);
5456 break;
5457 case CHAN_SOCKDATA:
5458 bufsize = pfd_send(c->u.pfd.s, data, length);
5459 break;
5460 case CHAN_AGENT:
5461 while (length > 0) {
5462 if (c->u.a.lensofar < 4) {
aa63ab7e 5463 unsigned int l = min(4 - c->u.a.lensofar, length);
51df0ab5 5464 memcpy(c->u.a.msglen + c->u.a.lensofar,
5465 data, l);
5466 data += l;
5467 length -= l;
5468 c->u.a.lensofar += l;
5469 }
5470 if (c->u.a.lensofar == 4) {
5471 c->u.a.totallen =
5472 4 + GET_32BIT(c->u.a.msglen);
5473 c->u.a.message = snewn(c->u.a.totallen,
5474 unsigned char);
5475 memcpy(c->u.a.message, c->u.a.msglen, 4);
5476 }
5477 if (c->u.a.lensofar >= 4 && length > 0) {
aa63ab7e 5478 unsigned int l =
51df0ab5 5479 min(c->u.a.totallen - c->u.a.lensofar,
5480 length);
5481 memcpy(c->u.a.message + c->u.a.lensofar,
5482 data, l);
5483 data += l;
5484 length -= l;
5485 c->u.a.lensofar += l;
5486 }
5487 if (c->u.a.lensofar == c->u.a.totallen) {
5488 void *reply;
5489 int replylen;
5490 if (agent_query(c->u.a.message,
5491 c->u.a.totallen,
5492 &reply, &replylen,
5493 ssh_agentf_callback, c))
5494 ssh_agentf_callback(c, reply, replylen);
5495 sfree(c->u.a.message);
5496 c->u.a.lensofar = 0;
5497 }
5498 }
5499 bufsize = 0;
5500 break;
5501 }
5502 /*
5503 * If we are not buffering too much data,
5504 * enlarge the window again at the remote side.
5505 */
5506 if (bufsize < OUR_V2_WINSIZE)
5507 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
5508 }
5509}
5510
5511static void ssh2_msg_channel_eof(Ssh ssh, struct Packet *pktin)
5512{
5513 unsigned i = ssh_pkt_getuint32(pktin);
5514 struct ssh_channel *c;
5515
5516 c = find234(ssh->channels, &i, ssh_channelfind);
5517 if (!c)
5518 return; /* nonexistent channel */
5519
5520 if (c->type == CHAN_X11) {
5521 /*
5522 * Remote EOF on an X11 channel means we should
5523 * wrap up and close the channel ourselves.
5524 */
5525 x11_close(c->u.x11.s);
5526 sshfwd_close(c);
5527 } else if (c->type == CHAN_AGENT) {
5528 sshfwd_close(c);
5529 } else if (c->type == CHAN_SOCKDATA) {
5530 pfd_close(c->u.pfd.s);
5531 sshfwd_close(c);
5532 }
5533}
5534
5535static void ssh2_msg_channel_close(Ssh ssh, struct Packet *pktin)
5536{
5537 unsigned i = ssh_pkt_getuint32(pktin);
5538 struct ssh_channel *c;
5539 struct Packet *pktout;
5540
5541 c = find234(ssh->channels, &i, ssh_channelfind);
5542 if (!c || ((int)c->remoteid) == -1) {
5543 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5544 c ? "half-open" : "nonexistent", i));
5545 return;
5546 }
5547 /* Do pre-close processing on the channel. */
5548 switch (c->type) {
5549 case CHAN_MAINSESSION:
5550 ssh->mainchan = NULL;
5551 update_specials_menu(ssh->frontend);
5552 break;
5553 case CHAN_X11:
5554 if (c->u.x11.s != NULL)
5555 x11_close(c->u.x11.s);
5556 sshfwd_close(c);
5557 break;
5558 case CHAN_AGENT:
5559 sshfwd_close(c);
5560 break;
5561 case CHAN_SOCKDATA:
5562 if (c->u.pfd.s != NULL)
5563 pfd_close(c->u.pfd.s);
5564 sshfwd_close(c);
5565 break;
5566 }
5567 if (c->closes == 0) {
5568 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
5569 ssh2_pkt_adduint32(pktout, c->remoteid);
5570 ssh2_pkt_send(ssh, pktout);
5571 }
5572 del234(ssh->channels, c);
5573 bufchain_clear(&c->v.v2.outbuffer);
5574 sfree(c);
5575
5576 /*
5577 * See if that was the last channel left open.
5578 * (This is only our termination condition if we're
5579 * not running in -N mode.)
5580 */
5581 if (!ssh->cfg.ssh_no_shell && count234(ssh->channels) == 0) {
5582 logevent("All channels closed. Disconnecting");
5583#if 0
5584 /*
5585 * We used to send SSH_MSG_DISCONNECT here,
5586 * because I'd believed that _every_ conforming
5587 * SSH2 connection had to end with a disconnect
5588 * being sent by at least one side; apparently
5589 * I was wrong and it's perfectly OK to
5590 * unceremoniously slam the connection shut
5591 * when you're done, and indeed OpenSSH feels
5592 * this is more polite than sending a
5593 * DISCONNECT. So now we don't.
5594 */
5595 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
5596 ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
5597 ssh2_pkt_addstring(s->pktout, "All open channels closed");
5598 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
5599 ssh2_pkt_send_noqueue(ssh, s->pktout);
5600#endif
5601 ssh_closing((Plug)ssh, NULL, 0, 0);
5602 }
5603}
5604
5605static void ssh2_msg_channel_open_confirmation(Ssh ssh, struct Packet *pktin)
5606{
5607 unsigned i = ssh_pkt_getuint32(pktin);
5608 struct ssh_channel *c;
5609 struct Packet *pktout;
5610
5611 c = find234(ssh->channels, &i, ssh_channelfind);
5612 if (!c)
5613 return; /* nonexistent channel */
5614 if (c->type != CHAN_SOCKDATA_DORMANT)
5615 return; /* dunno why they're confirming this */
5616 c->remoteid = ssh_pkt_getuint32(pktin);
5617 c->type = CHAN_SOCKDATA;
5618 c->v.v2.remwindow = ssh_pkt_getuint32(pktin);
5619 c->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin);
5620 if (c->u.pfd.s)
5621 pfd_confirm(c->u.pfd.s);
5622 if (c->closes) {
5623 /*
5624 * We have a pending close on this channel,
5625 * which we decided on before the server acked
5626 * the channel open. So now we know the
5627 * remoteid, we can close it again.
5628 */
5629 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
5630 ssh2_pkt_adduint32(pktout, c->remoteid);
5631 ssh2_pkt_send(ssh, pktout);
5632 }
5633}
5634
5635static void ssh2_msg_channel_open_failure(Ssh ssh, struct Packet *pktin)
5636{
5637 static const char *const reasons[] = {
5638 "<unknown reason code>",
5639 "Administratively prohibited",
5640 "Connect failed",
5641 "Unknown channel type",
5642 "Resource shortage",
5643 };
5644 unsigned i = ssh_pkt_getuint32(pktin);
5645 unsigned reason_code;
5646 char *reason_string;
5647 int reason_length;
5648 char *message;
5649 struct ssh_channel *c;
5650 c = find234(ssh->channels, &i, ssh_channelfind);
5651 if (!c)
5652 return; /* nonexistent channel */
5653 if (c->type != CHAN_SOCKDATA_DORMANT)
5654 return; /* dunno why they're failing this */
5655
5656 reason_code = ssh_pkt_getuint32(pktin);
5657 if (reason_code >= lenof(reasons))
5658 reason_code = 0; /* ensure reasons[reason_code] in range */
5659 ssh_pkt_getstring(pktin, &reason_string, &reason_length);
5660 message = dupprintf("Forwarded connection refused by"
5661 " server: %s [%.*s]", reasons[reason_code],
5662 reason_length, reason_string);
5663 logevent(message);
5664 sfree(message);
5665
5666 pfd_close(c->u.pfd.s);
5667
5668 del234(ssh->channels, c);
5669 sfree(c);
5670}
5671
5672static void ssh2_msg_channel_request(Ssh ssh, struct Packet *pktin)
5673{
5674 unsigned localid;
5675 char *type;
5676 int typelen, want_reply;
5677 int reply = SSH2_MSG_CHANNEL_FAILURE; /* default */
5678 struct ssh_channel *c;
5679 struct Packet *pktout;
5680
5681 localid = ssh_pkt_getuint32(pktin);
5682 ssh_pkt_getstring(pktin, &type, &typelen);
5683 want_reply = ssh2_pkt_getbool(pktin);
5684
5685 /*
5686 * First, check that the channel exists. Otherwise,
5687 * we can instantly disconnect with a rude message.
5688 */
5689 c = find234(ssh->channels, &localid, ssh_channelfind);
5690 if (!c) {
5691 char buf[80];
5692 sprintf(buf, "Received channel request for nonexistent"
5693 " channel %d", localid);
5694 logevent(buf);
5695 pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
5696 ssh2_pkt_adduint32(pktout, SSH2_DISCONNECT_BY_APPLICATION);
5697 ssh2_pkt_addstring(pktout, buf);
5698 ssh2_pkt_addstring(pktout, "en"); /* language tag */
5699 ssh2_pkt_send_noqueue(ssh, pktout);
5700 connection_fatal(ssh->frontend, "%s", buf);
5701 ssh_closing((Plug)ssh, NULL, 0, 0);
5702 return;
5703 }
5704
5705 /*
5706 * Having got the channel number, we now look at
5707 * the request type string to see if it's something
5708 * we recognise.
5709 */
5710 if (c == ssh->mainchan) {
5711 /*
5712 * We recognise "exit-status" and "exit-signal" on
5713 * the primary channel.
5714 */
5715 if (typelen == 11 &&
5716 !memcmp(type, "exit-status", 11)) {
5717
5718 ssh->exitcode = ssh_pkt_getuint32(pktin);
5719 logeventf(ssh, "Server sent command exit status %d",
5720 ssh->exitcode);
5721 reply = SSH2_MSG_CHANNEL_SUCCESS;
5722
5723 } else if (typelen == 11 &&
5724 !memcmp(type, "exit-signal", 11)) {
5725
5726 int is_plausible = TRUE, is_int = FALSE;
5727 char *fmt_sig = "", *fmt_msg = "";
5728 char *msg;
5729 int msglen = 0, core = FALSE;
5730 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
5731 * provide an `int' for the signal, despite its
5732 * having been a `string' in the drafts since at
5733 * least 2001. (Fixed in session.c 1.147.) Try to
5734 * infer which we can safely parse it as. */
5735 {
5736 unsigned char *p = pktin->body +
5737 pktin->savedpos;
5738 long len = pktin->length - pktin->savedpos;
5739 unsigned long num = GET_32BIT(p); /* what is it? */
5740 /* If it's 0, it hardly matters; assume string */
5741 if (num == 0) {
5742 is_int = FALSE;
5743 } else {
5744 int maybe_int = FALSE, maybe_str = FALSE;
5745#define CHECK_HYPOTHESIS(offset, result) \
5746 do { \
5747 long q = offset; \
5748 if (q >= 0 && q+4 <= len) { \
5749 q = q + 4 + GET_32BIT(p+q); \
5750 if (q >= 0 && q+4 <= len && \
5751 (q = q + 4 + GET_32BIT(p+q)) && q == len) \
5752 result = TRUE; \
5753 } \
5754 } while(0)
5755 CHECK_HYPOTHESIS(4+1, maybe_int);
5756 CHECK_HYPOTHESIS(4+num+1, maybe_str);
5757#undef CHECK_HYPOTHESIS
5758 if (maybe_int && !maybe_str)
5759 is_int = TRUE;
5760 else if (!maybe_int && maybe_str)
5761 is_int = FALSE;
5762 else
5763 /* Crikey. Either or neither. Panic. */
5764 is_plausible = FALSE;
5765 }
5766 }
5767 if (is_plausible) {
5768 if (is_int) {
5769 /* Old non-standard OpenSSH. */
5770 int signum = ssh_pkt_getuint32(pktin);
5771 fmt_sig = dupprintf(" %d", signum);
5772 } else {
5773 /* As per the drafts. */
5774 char *sig;
5775 int siglen;
5776 ssh_pkt_getstring(pktin, &sig, &siglen);
5777 /* Signal name isn't supposed to be blank, but
5778 * let's cope gracefully if it is. */
5779 if (siglen) {
5780 fmt_sig = dupprintf(" \"%.*s\"",
5781 siglen, sig);
5782 }
5783 }
5784 core = ssh2_pkt_getbool(pktin);
5785 ssh_pkt_getstring(pktin, &msg, &msglen);
5786 if (msglen) {
5787 fmt_msg = dupprintf(" (\"%.*s\")", msglen, msg);
5788 }
5789 /* ignore lang tag */
5790 } /* else don't attempt to parse */
5791 logeventf(ssh, "Server exited on signal%s%s%s",
5792 fmt_sig, core ? " (core dumped)" : "",
5793 fmt_msg);
5794 if (*fmt_sig) sfree(fmt_sig);
5795 if (*fmt_msg) sfree(fmt_msg);
5796 reply = SSH2_MSG_CHANNEL_SUCCESS;
5797
5798 }
5799 } else {
5800 /*
5801 * This is a channel request we don't know
5802 * about, so we now either ignore the request
5803 * or respond with CHANNEL_FAILURE, depending
5804 * on want_reply.
5805 */
5806 reply = SSH2_MSG_CHANNEL_FAILURE;
5807 }
5808 if (want_reply) {
5809 pktout = ssh2_pkt_init(reply);
5810 ssh2_pkt_adduint32(pktout, c->remoteid);
5811 ssh2_pkt_send(ssh, pktout);
5812 }
5813}
5814
5815static void ssh2_msg_global_request(Ssh ssh, struct Packet *pktin)
5816{
5817 char *type;
5818 int typelen, want_reply;
5819 struct Packet *pktout;
5820
5821 ssh_pkt_getstring(pktin, &type, &typelen);
5822 want_reply = ssh2_pkt_getbool(pktin);
5823
5824 /*
5825 * We currently don't support any global requests
5826 * at all, so we either ignore the request or
5827 * respond with REQUEST_FAILURE, depending on
5828 * want_reply.
5829 */
5830 if (want_reply) {
5831 pktout = ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE);
5832 ssh2_pkt_send(ssh, pktout);
5833 }
5834}
5835
5836static void ssh2_msg_channel_open(Ssh ssh, struct Packet *pktin)
5837{
5838 char *type;
5839 int typelen;
5840 char *peeraddr;
5841 int peeraddrlen;
5842 int peerport;
5843 char *error = NULL;
5844 struct ssh_channel *c;
5845 unsigned remid, winsize, pktsize;
5846 struct Packet *pktout;
5847
5848 ssh_pkt_getstring(pktin, &type, &typelen);
5849 c = snew(struct ssh_channel);
5850 c->ssh = ssh;
5851
5852 remid = ssh_pkt_getuint32(pktin);
5853 winsize = ssh_pkt_getuint32(pktin);
5854 pktsize = ssh_pkt_getuint32(pktin);
5855
5856 if (typelen == 3 && !memcmp(type, "x11", 3)) {
5857 char *addrstr;
5858
5859 ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
5860 addrstr = snewn(peeraddrlen+1, char);
5861 memcpy(addrstr, peeraddr, peeraddrlen);
5862 addrstr[peeraddrlen] = '\0';
5863 peerport = ssh_pkt_getuint32(pktin);
5864
5865 logeventf(ssh, "Received X11 connect request from %s:%d",
5866 addrstr, peerport);
5867
5868 if (!ssh->X11_fwd_enabled)
5869 error = "X11 forwarding is not enabled";
5870 else if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
5871 ssh->x11auth, addrstr, peerport,
5872 &ssh->cfg) != NULL) {
5873 error = "Unable to open an X11 connection";
5874 } else {
5875 logevent("Opening X11 forward connection succeeded");
5876 c->type = CHAN_X11;
5877 }
5878
5879 sfree(addrstr);
5880 } else if (typelen == 15 &&
5881 !memcmp(type, "forwarded-tcpip", 15)) {
5882 struct ssh_rportfwd pf, *realpf;
5883 char *dummy;
5884 int dummylen;
5885 ssh_pkt_getstring(pktin, &dummy, &dummylen);/* skip address */
5886 pf.sport = ssh_pkt_getuint32(pktin);
5887 ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
5888 peerport = ssh_pkt_getuint32(pktin);
5889 realpf = find234(ssh->rportfwds, &pf, NULL);
5890 logeventf(ssh, "Received remote port %d open request "
5891 "from %s:%d", pf.sport, peeraddr, peerport);
5892 if (realpf == NULL) {
5893 error = "Remote port is not recognised";
5894 } else {
5895 const char *e = pfd_newconnect(&c->u.pfd.s,
5896 realpf->dhost,
5897 realpf->dport, c,
05581745 5898 &ssh->cfg,
5899 realpf->pfrec->addressfamily);
51df0ab5 5900 logeventf(ssh, "Attempting to forward remote port to "
5901 "%s:%d", realpf->dhost, realpf->dport);
5902 if (e != NULL) {
5903 logeventf(ssh, "Port open failed: %s", e);
5904 error = "Port open failed";
5905 } else {
5906 logevent("Forwarded port opened successfully");
5907 c->type = CHAN_SOCKDATA;
5908 }
5909 }
5910 } else if (typelen == 22 &&
5911 !memcmp(type, "auth-agent@openssh.com", 3)) {
5912 if (!ssh->agentfwd_enabled)
5913 error = "Agent forwarding is not enabled";
5914 else {
5915 c->type = CHAN_AGENT; /* identify channel type */
5916 c->u.a.lensofar = 0;
5917 }
5918 } else {
5919 error = "Unsupported channel type requested";
5920 }
5921
5922 c->remoteid = remid;
5923 if (error) {
5924 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE);
5925 ssh2_pkt_adduint32(pktout, c->remoteid);
5926 ssh2_pkt_adduint32(pktout, SSH2_OPEN_CONNECT_FAILED);
5927 ssh2_pkt_addstring(pktout, error);
5928 ssh2_pkt_addstring(pktout, "en"); /* language tag */
5929 ssh2_pkt_send(ssh, pktout);
5930 logeventf(ssh, "Rejected channel open: %s", error);
5931 sfree(c);
5932 } else {
5933 c->localid = alloc_channel_id(ssh);
5934 c->closes = 0;
5935 c->v.v2.locwindow = OUR_V2_WINSIZE;
5936 c->v.v2.remwindow = winsize;
5937 c->v.v2.remmaxpkt = pktsize;
5938 bufchain_init(&c->v.v2.outbuffer);
5939 add234(ssh->channels, c);
5940 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
5941 ssh2_pkt_adduint32(pktout, c->remoteid);
5942 ssh2_pkt_adduint32(pktout, c->localid);
5943 ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);
5944 ssh2_pkt_adduint32(pktout, 0x4000UL); /* our max pkt size */
5945 ssh2_pkt_send(ssh, pktout);
5946 }
5947}
5948
783415f8 5949/*
7cca0d81 5950 * Handle the SSH2 userauth and connection layers.
5951 */
ff3187f6 5952static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
5953 struct Packet *pktin)
7cca0d81 5954{
51470298 5955 struct do_ssh2_authconn_state {
5956 enum {
5957 AUTH_INVALID, AUTH_PUBLICKEY_AGENT, AUTH_PUBLICKEY_FILE,
5958 AUTH_PASSWORD,
5959 AUTH_KEYBOARD_INTERACTIVE
5960 } method;
5961 enum {
5962 AUTH_TYPE_NONE,
5963 AUTH_TYPE_PUBLICKEY,
5964 AUTH_TYPE_PUBLICKEY_OFFER_LOUD,
5965 AUTH_TYPE_PUBLICKEY_OFFER_QUIET,
5966 AUTH_TYPE_PASSWORD,
5967 AUTH_TYPE_KEYBOARD_INTERACTIVE,
5968 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
5969 } type;
5970 int gotit, need_pw, can_pubkey, can_passwd, can_keyb_inter;
6ac3a551 5971 int tried_pubkey_config, tried_agent;
5972 int kbd_inter_running, kbd_inter_refused;
51470298 5973 int we_are_in;
5974 int num_prompts, curr_prompt, echo;
5975 char username[100];
5976 int got_username;
85fdbe25 5977 char pwprompt[512];
51470298 5978 char password[100];
5979 void *publickey_blob;
5980 int publickey_bloblen;
5981 unsigned char request[5], *response, *p;
5982 int responselen;
5983 int keyi, nkeys;
5984 int authed;
5985 char *pkblob, *alg, *commentp;
5986 int pklen, alglen, commentlen;
5987 int siglen, retlen, len;
5988 char *q, *agentreq, *ret;
5989 int try_send;
73feed4f 5990 int num_env, env_left, env_ok;
ff3187f6 5991 struct Packet *pktout;
51470298 5992 };
5993 crState(do_ssh2_authconn_state);
5994
5995 crBegin(ssh->do_ssh2_authconn_crstate);
e5574168 5996
7cca0d81 5997 /*
5998 * Request userauth protocol, and await a response to it.
5999 */
ff3187f6 6000 s->pktout = ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
6001 ssh2_pkt_addstring(s->pktout, "ssh-userauth");
6002 ssh2_pkt_send(ssh, s->pktout);
6003 crWaitUntilV(pktin);
6004 if (pktin->type != SSH2_MSG_SERVICE_ACCEPT) {
6b5cf8b4 6005 bombout(("Server refused user authentication protocol"));
7ffdbc1a 6006 crStopV;
8d5de777 6007 }
7cca0d81 6008
6009 /*
1408a877 6010 * We repeat this whole loop, including the username prompt,
6011 * until we manage a successful authentication. If the user
51470298 6012 * types the wrong _password_, they can be sent back to the
6013 * beginning to try another username, if this is configured on.
6014 * (If they specify a username in the config, they are never
6015 * asked, even if they do give a wrong password.)
1408a877 6016 *
6017 * I think this best serves the needs of
6018 *
6019 * - the people who have no configuration, no keys, and just
6020 * want to try repeated (username,password) pairs until they
6021 * type both correctly
6022 *
6023 * - people who have keys and configuration but occasionally
6024 * need to fall back to passwords
6025 *
6026 * - people with a key held in Pageant, who might not have
6027 * logged in to a particular machine before; so they want to
6028 * type a username, and then _either_ their key will be
6029 * accepted, _or_ they will type a password. If they mistype
6030 * the username they will want to be able to get back and
6031 * retype it!
7cca0d81 6032 */
51470298 6033 s->username[0] = '\0';
6034 s->got_username = FALSE;
1408a877 6035 do {
1408a877 6036 /*
6037 * Get a username.
6038 */
86916870 6039 if (s->got_username && !ssh->cfg.change_username) {
5bb641e1 6040 /*
6041 * We got a username last time round this loop, and
6042 * with change_username turned off we don't try to get
6043 * it again.
6044 */
aa09f7d0 6045 } else if (!*ssh->cfg.username) {
c0a81592 6046 if (ssh_get_line && !ssh_getline_pw_only) {
32874aea 6047 if (!ssh_get_line("login as: ",
51470298 6048 s->username, sizeof(s->username), FALSE)) {
32874aea 6049 /*
6050 * get_line failed to get a username.
6051 * Terminate.
6052 */
6053 logevent("No username provided. Abandoning session.");
3bb2f322 6054 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 6055 crStopV;
32874aea 6056 }
6057 } else {
51470298 6058 int ret; /* need not be saved across crReturn */
6059 c_write_str(ssh, "login as: ");
6060 ssh->send_ok = 1;
6061 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
0405e71f 6062 do {
ff3187f6 6063 crWaitUntilV(!pktin);
51470298 6064 ret = process_userpass_input(ssh, in, inlen);
0405e71f 6065 } while (ret == 0);
6066 if (ret < 0)
6067 cleanup_exit(0);
4ca0c9d1 6068 c_write_str(ssh, "\r\n");
32874aea 6069 }
51470298 6070 s->username[strcspn(s->username, "\n\r")] = '\0';
7cca0d81 6071 } else {
57356d63 6072 char *stuff;
86916870 6073 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
51470298 6074 s->username[sizeof(s->username)-1] = '\0';
65a22376 6075 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
57356d63 6076 stuff = dupprintf("Using username \"%s\".\r\n", s->username);
51470298 6077 c_write_str(ssh, stuff);
57356d63 6078 sfree(stuff);
7cca0d81 6079 }
6080 }
51470298 6081 s->got_username = TRUE;
7cca0d81 6082
65a22376 6083 /*
1408a877 6084 * Send an authentication request using method "none": (a)
6085 * just in case it succeeds, and (b) so that we know what
6086 * authentication methods we can usefully try next.
65a22376 6087 */
51470298 6088 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6089
ff3187f6 6090 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6091 ssh2_pkt_addstring(s->pktout, s->username);
6092 ssh2_pkt_addstring(s->pktout, "ssh-connection");/* service requested */
6093 ssh2_pkt_addstring(s->pktout, "none"); /* method */
6094 ssh2_pkt_send(ssh, s->pktout);
51470298 6095 s->type = AUTH_TYPE_NONE;
6096 s->gotit = FALSE;
6097 s->we_are_in = FALSE;
6098
6099 s->tried_pubkey_config = FALSE;
6100 s->tried_agent = FALSE;
51470298 6101 s->kbd_inter_running = FALSE;
6ac3a551 6102 s->kbd_inter_refused = FALSE;
86916870 6103 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
9a30e26b 6104 if (!filename_is_null(ssh->cfg.keyfile)) {
231ee168 6105 int keytype;
6c6d9ed9 6106 logeventf(ssh, "Reading private key file \"%.150s\"",
6107 filename_to_str(&ssh->cfg.keyfile));
9a30e26b 6108 keytype = key_type(&ssh->cfg.keyfile);
51470298 6109 if (keytype == SSH_KEYTYPE_SSH2) {
6110 s->publickey_blob =
9a30e26b 6111 ssh2_userkey_loadpub(&ssh->cfg.keyfile, NULL,
222d54dc 6112 &s->publickey_bloblen, NULL);
51470298 6113 } else {
57356d63 6114 char *msgbuf;
c2ad7d0d 6115 logeventf(ssh, "Unable to use this key file (%s)",
a8327734 6116 key_type_to_str(keytype));
57356d63 6117 msgbuf = dupprintf("Unable to use key file \"%.150s\""
6c6d9ed9 6118 " (%s)\r\n",
6119 filename_to_str(&ssh->cfg.keyfile),
57356d63 6120 key_type_to_str(keytype));
51470298 6121 c_write_str(ssh, msgbuf);
57356d63 6122 sfree(msgbuf);
51470298 6123 s->publickey_blob = NULL;
231ee168 6124 }
396778f1 6125 } else
51470298 6126 s->publickey_blob = NULL;
65a22376 6127
1408a877 6128 while (1) {
6129 /*
6130 * Wait for the result of the last authentication request.
6131 */
51470298 6132 if (!s->gotit)
ff3187f6 6133 crWaitUntilV(pktin);
6134 while (pktin->type == SSH2_MSG_USERAUTH_BANNER) {
32874aea 6135 char *banner;
6136 int size;
6137 /*
6138 * Don't show the banner if we're operating in
6139 * non-verbose non-interactive mode. (It's probably
6140 * a script, which means nobody will read the
6141 * banner _anyway_, and moreover the printing of
6142 * the banner will screw up processing on the
6143 * output of (say) plink.)
6144 */
6145 if (flags & (FLAG_VERBOSE | FLAG_INTERACTIVE)) {
ff3187f6 6146 ssh_pkt_getstring(pktin, &banner, &size);
32874aea 6147 if (banner)
51470298 6148 c_write_untrusted(ssh, banner, size);
32874aea 6149 }
ff3187f6 6150 crWaitUntilV(pktin);
1408a877 6151 }
ff3187f6 6152 if (pktin->type == SSH2_MSG_USERAUTH_SUCCESS) {
1408a877 6153 logevent("Access granted");
51470298 6154 s->we_are_in = TRUE;
1408a877 6155 break;
6156 }
65a22376 6157
51470298 6158 if (s->kbd_inter_running &&
ff3187f6 6159 pktin->type == SSH2_MSG_USERAUTH_INFO_REQUEST) {
b3186d64 6160 /*
45068b27 6161 * This is either a further set-of-prompts packet
6162 * in keyboard-interactive authentication, or it's
6163 * the same one and we came back here with `gotit'
6164 * set. In the former case, we must reset the
6165 * curr_prompt variable.
b3186d64 6166 */
51470298 6167 if (!s->gotit)
6168 s->curr_prompt = 0;
4c6e53e3 6169 } else if (pktin->type == SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ) {
6170 /* FIXME: perhaps we should support this? */
6171 bombout(("PASSWD_CHANGEREQ not yet supported"));
6172 crStopV;
ff3187f6 6173 } else if (pktin->type != SSH2_MSG_USERAUTH_FAILURE) {
6b5cf8b4 6174 bombout(("Strange packet received during authentication: type %d",
ff3187f6 6175 pktin->type));
7ffdbc1a 6176 crStopV;
65a22376 6177 }
6178
51470298 6179 s->gotit = FALSE;
65a22376 6180
1408a877 6181 /*
6182 * OK, we're now sitting on a USERAUTH_FAILURE message, so
6183 * we can look at the string in it and know what we can
6184 * helpfully try next.
6185 */
ff3187f6 6186 if (pktin->type == SSH2_MSG_USERAUTH_FAILURE) {
1408a877 6187 char *methods;
6188 int methlen;
ff3187f6 6189 ssh_pkt_getstring(pktin, &methods, &methlen);
51470298 6190 s->kbd_inter_running = FALSE;
ff3187f6 6191 if (!ssh2_pkt_getbool(pktin)) {
1408a877 6192 /*
6193 * We have received an unequivocal Access
6194 * Denied. This can translate to a variety of
6195 * messages:
6196 *
6197 * - if we'd just tried "none" authentication,
6198 * it's not worth printing anything at all
6199 *
6200 * - if we'd just tried a public key _offer_,
6201 * the message should be "Server refused our
6202 * key" (or no message at all if the key
6203 * came from Pageant)
6204 *
6205 * - if we'd just tried anything else, the
6206 * message really should be "Access denied".
6207 *
6208 * Additionally, if we'd just tried password
6209 * authentication, we should break out of this
6210 * whole loop so as to go back to the username
91f57d1f 6211 * prompt (iff we're configured to allow
6212 * username change attempts).
1408a877 6213 */
51470298 6214 if (s->type == AUTH_TYPE_NONE) {
1408a877 6215 /* do nothing */
51470298 6216 } else if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD ||
6217 s->type == AUTH_TYPE_PUBLICKEY_OFFER_QUIET) {
6218 if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD)
6219 c_write_str(ssh, "Server refused our key\r\n");
1408a877 6220 logevent("Server refused public key");
51470298 6221 } else if (s->type==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET) {
4bdf7c46 6222 /* server declined keyboard-interactive; ignore */
1408a877 6223 } else {
51470298 6224 c_write_str(ssh, "Access denied\r\n");
1408a877 6225 logevent("Access denied");
91f57d1f 6226 if (s->type == AUTH_TYPE_PASSWORD &&
6227 ssh->cfg.change_username) {
6c9dce7c 6228 /* XXX perhaps we should allow
6229 * keyboard-interactive to do this too? */
51470298 6230 s->we_are_in = FALSE;
1408a877 6231 break;
6232 }
6233 }
6234 } else {
51470298 6235 c_write_str(ssh, "Further authentication required\r\n");
1408a877 6236 logevent("Further authentication required");
6237 }
65a22376 6238
51470298 6239 s->can_pubkey =
32874aea 6240 in_commasep_string("publickey", methods, methlen);
51470298 6241 s->can_passwd =
32874aea 6242 in_commasep_string("password", methods, methlen);
86916870 6243 s->can_keyb_inter = ssh->cfg.try_ki_auth &&
761187b6 6244 in_commasep_string("keyboard-interactive", methods, methlen);
1408a877 6245 }
65a22376 6246
51470298 6247 s->method = 0;
6248 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
954a9540 6249 s->need_pw = FALSE;
65a22376 6250
0405e71f 6251 /*
6252 * Most password/passphrase prompts will be
6253 * non-echoing, so we set this to 0 by default.
6254 * Exception is that some keyboard-interactive prompts
6255 * can be echoing, in which case we'll set this to 1.
6256 */
51470298 6257 s->echo = 0;
0405e71f 6258
51470298 6259 if (!s->method && s->can_pubkey &&
6260 agent_exists() && !s->tried_agent) {
1983e559 6261 /*
6262 * Attempt public-key authentication using Pageant.
6263 */
1983e559 6264 void *r;
51470298 6265 s->authed = FALSE;
1983e559 6266
51470298 6267 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6268 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
00db133f 6269
51470298 6270 s->tried_agent = TRUE;
1983e559 6271
6272 logevent("Pageant is running. Requesting keys.");
6273
6274 /* Request the keys held by the agent. */
51470298 6275 PUT_32BIT(s->request, 1);
6276 s->request[4] = SSH2_AGENTC_REQUEST_IDENTITIES;
839f10db 6277 if (!agent_query(s->request, 5, &r, &s->responselen,
6278 ssh_agent_callback, ssh)) {
6279 do {
6280 crReturnV;
ff3187f6 6281 if (pktin) {
839f10db 6282 bombout(("Unexpected data from server while"
6283 " waiting for agent response"));
6284 crStopV;
6285 }
ff3187f6 6286 } while (pktin || inlen > 0);
839f10db 6287 r = ssh->agent_response;
6288 s->responselen = ssh->agent_response_len;
6289 }
51470298 6290 s->response = (unsigned char *) r;
6291 if (s->response && s->responselen >= 5 &&
6292 s->response[4] == SSH2_AGENT_IDENTITIES_ANSWER) {
6293 s->p = s->response + 5;
6294 s->nkeys = GET_32BIT(s->p);
6295 s->p += 4;
32874aea 6296 {
6297 char buf[64];
51470298 6298 sprintf(buf, "Pageant has %d SSH2 keys", s->nkeys);
32874aea 6299 logevent(buf);
6300 }
51470298 6301 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
2d466ffd 6302 void *vret;
1983e559 6303
32874aea 6304 {
6305 char buf[64];
51470298 6306 sprintf(buf, "Trying Pageant key #%d", s->keyi);
32874aea 6307 logevent(buf);
6308 }
51470298 6309 s->pklen = GET_32BIT(s->p);
6310 s->p += 4;
6311 if (s->publickey_blob &&
6312 s->pklen == s->publickey_bloblen &&
6313 !memcmp(s->p, s->publickey_blob,
6314 s->publickey_bloblen)) {
396778f1 6315 logevent("This key matches configured key file");
51470298 6316 s->tried_pubkey_config = 1;
396778f1 6317 }
d8baa528 6318 s->pkblob = (char *)s->p;
51470298 6319 s->p += s->pklen;
6320 s->alglen = GET_32BIT(s->pkblob);
6321 s->alg = s->pkblob + 4;
6322 s->commentlen = GET_32BIT(s->p);
6323 s->p += 4;
d8baa528 6324 s->commentp = (char *)s->p;
51470298 6325 s->p += s->commentlen;
ff3187f6 6326 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6327 ssh2_pkt_addstring(s->pktout, s->username);
6328 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6329 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6330 ssh2_pkt_addbool(s->pktout, FALSE); /* no signature included */
6331 ssh2_pkt_addstring_start(s->pktout);
6332 ssh2_pkt_addstring_data(s->pktout, s->alg, s->alglen);
6333 ssh2_pkt_addstring_start(s->pktout);
6334 ssh2_pkt_addstring_data(s->pktout, s->pkblob, s->pklen);
6335 ssh2_pkt_send(ssh, s->pktout);
6336
6337 crWaitUntilV(pktin);
6338 if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
1983e559 6339 logevent("Key refused");
6340 continue;
6341 }
6342
32874aea 6343 if (flags & FLAG_VERBOSE) {
51470298 6344 c_write_str(ssh, "Authenticating with "
6345 "public key \"");
6346 c_write(ssh, s->commentp, s->commentlen);
6347 c_write_str(ssh, "\" from agent\r\n");
32874aea 6348 }
1983e559 6349
6350 /*
6351 * Server is willing to accept the key.
6352 * Construct a SIGN_REQUEST.
6353 */
ff3187f6 6354 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6355 ssh2_pkt_addstring(s->pktout, s->username);
6356 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6357 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6358 ssh2_pkt_addbool(s->pktout, TRUE);
6359 ssh2_pkt_addstring_start(s->pktout);
6360 ssh2_pkt_addstring_data(s->pktout, s->alg, s->alglen);
6361 ssh2_pkt_addstring_start(s->pktout);
6362 ssh2_pkt_addstring_data(s->pktout, s->pkblob, s->pklen);
6363
6364 s->siglen = s->pktout->length - 5 + 4 + 20;
dda87a28 6365 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
6366 s->siglen -= 4;
51470298 6367 s->len = 1; /* message type */
6368 s->len += 4 + s->pklen; /* key blob */
6369 s->len += 4 + s->siglen; /* data to sign */
6370 s->len += 4; /* flags */
3d88e64d 6371 s->agentreq = snewn(4 + s->len, char);
51470298 6372 PUT_32BIT(s->agentreq, s->len);
6373 s->q = s->agentreq + 4;
6374 *s->q++ = SSH2_AGENTC_SIGN_REQUEST;
6375 PUT_32BIT(s->q, s->pklen);
6376 s->q += 4;
6377 memcpy(s->q, s->pkblob, s->pklen);
6378 s->q += s->pklen;
6379 PUT_32BIT(s->q, s->siglen);
6380 s->q += 4;
1983e559 6381 /* Now the data to be signed... */
dda87a28 6382 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
6383 PUT_32BIT(s->q, 20);
6384 s->q += 4;
6385 }
51470298 6386 memcpy(s->q, ssh->v2_session_id, 20);
6387 s->q += 20;
ff3187f6 6388 memcpy(s->q, s->pktout->data + 5,
6389 s->pktout->length - 5);
6390 s->q += s->pktout->length - 5;
1983e559 6391 /* And finally the (zero) flags word. */
51470298 6392 PUT_32BIT(s->q, 0);
839f10db 6393 if (!agent_query(s->agentreq, s->len + 4,
6394 &vret, &s->retlen,
6395 ssh_agent_callback, ssh)) {
6396 do {
6397 crReturnV;
ff3187f6 6398 if (pktin) {
839f10db 6399 bombout(("Unexpected data from server"
6400 " while waiting for agent"
6401 " response"));
6402 crStopV;
6403 }
ff3187f6 6404 } while (pktin || inlen > 0);
839f10db 6405 vret = ssh->agent_response;
6406 s->retlen = ssh->agent_response_len;
6407 }
51470298 6408 s->ret = vret;
6409 sfree(s->agentreq);
6410 if (s->ret) {
6411 if (s->ret[4] == SSH2_AGENT_SIGN_RESPONSE) {
1983e559 6412 logevent("Sending Pageant's response");
ff3187f6 6413 ssh2_add_sigblob(ssh, s->pktout,
6414 s->pkblob, s->pklen,
51470298 6415 s->ret + 9,
6416 GET_32BIT(s->ret + 5));
ff3187f6 6417 ssh2_pkt_send(ssh, s->pktout);
51470298 6418 s->authed = TRUE;
1983e559 6419 break;
6420 } else {
32874aea 6421 logevent
6422 ("Pageant failed to answer challenge");
51470298 6423 sfree(s->ret);
1983e559 6424 }
6425 }
6426 }
51470298 6427 if (s->authed)
1983e559 6428 continue;
6429 }
29b1d0b3 6430 sfree(s->response);
1983e559 6431 }
6432
51470298 6433 if (!s->method && s->can_pubkey && s->publickey_blob
6434 && !s->tried_pubkey_config) {
1408a877 6435 unsigned char *pub_blob;
6436 char *algorithm, *comment;
6437 int pub_blob_len;
65a22376 6438
51470298 6439 s->tried_pubkey_config = TRUE;
65a22376 6440
51470298 6441 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6442 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
00db133f 6443
65a22376 6444 /*
1408a877 6445 * Try the public key supplied in the configuration.
6446 *
6447 * First, offer the public blob to see if the server is
6448 * willing to accept it.
65a22376 6449 */
d8baa528 6450 pub_blob =
9a30e26b 6451 (unsigned char *)ssh2_userkey_loadpub(&ssh->cfg.keyfile,
d8baa528 6452 &algorithm,
222d54dc 6453 &pub_blob_len,
6454 NULL);
1408a877 6455 if (pub_blob) {
ff3187f6 6456 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6457 ssh2_pkt_addstring(s->pktout, s->username);
6458 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6459 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6460 ssh2_pkt_addbool(s->pktout, FALSE); /* no signature included */
6461 ssh2_pkt_addstring(s->pktout, algorithm);
6462 ssh2_pkt_addstring_start(s->pktout);
6463 ssh2_pkt_addstring_data(s->pktout, (char *)pub_blob,
d8baa528 6464 pub_blob_len);
ff3187f6 6465 ssh2_pkt_send(ssh, s->pktout);
a03c9f9c 6466 logevent("Offered public key");
1408a877 6467
ff3187f6 6468 crWaitUntilV(pktin);
6469 if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
51470298 6470 s->gotit = TRUE;
6471 s->type = AUTH_TYPE_PUBLICKEY_OFFER_LOUD;
32874aea 6472 continue; /* key refused; give up on it */
1408a877 6473 }
65a22376 6474
1408a877 6475 logevent("Offer of public key accepted");
65a22376 6476 /*
1408a877 6477 * Actually attempt a serious authentication using
6478 * the key.
65a22376 6479 */
9a30e26b 6480 if (ssh2_userkey_encrypted(&ssh->cfg.keyfile, &comment)) {
51470298 6481 sprintf(s->pwprompt,
32874aea 6482 "Passphrase for key \"%.100s\": ",
6483 comment);
51470298 6484 s->need_pw = TRUE;
1408a877 6485 } else {
51470298 6486 s->need_pw = FALSE;
1408a877 6487 }
4e520718 6488 if (flags & FLAG_VERBOSE) {
6489 c_write_str(ssh, "Authenticating with public key \"");
6490 c_write_str(ssh, comment);
6491 c_write_str(ssh, "\"\r\n");
6492 }
51470298 6493 s->method = AUTH_PUBLICKEY_FILE;
65a22376 6494 }
1408a877 6495 }
6496
6f64ce13 6497 if (!s->method && s->can_keyb_inter && !s->kbd_inter_refused &&
6498 !s->kbd_inter_running) {
51470298 6499 s->method = AUTH_KEYBOARD_INTERACTIVE;
6500 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
af659722 6501
51470298 6502 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6503 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
00db133f 6504
ff3187f6 6505 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6506 ssh2_pkt_addstring(s->pktout, s->username);
6507 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6508 ssh2_pkt_addstring(s->pktout, "keyboard-interactive"); /* method */
6509 ssh2_pkt_addstring(s->pktout, ""); /* lang */
6510 ssh2_pkt_addstring(s->pktout, "");
6511 ssh2_pkt_send(ssh, s->pktout);
6512
6513 crWaitUntilV(pktin);
6514 if (pktin->type != SSH2_MSG_USERAUTH_INFO_REQUEST) {
6515 if (pktin->type == SSH2_MSG_USERAUTH_FAILURE)
51470298 6516 s->gotit = TRUE;
af659722 6517 logevent("Keyboard-interactive authentication refused");
51470298 6518 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET;
6ac3a551 6519 s->kbd_inter_refused = TRUE; /* don't try it again */
af659722 6520 continue;
6521 }
6522
51470298 6523 s->kbd_inter_running = TRUE;
6524 s->curr_prompt = 0;
af659722 6525 }
6526
51470298 6527 if (s->kbd_inter_running) {
6528 s->method = AUTH_KEYBOARD_INTERACTIVE;
6529 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
af659722 6530
51470298 6531 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6532 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
00db133f 6533
51470298 6534 if (s->curr_prompt == 0) {
45068b27 6535 /*
6536 * We've got a fresh USERAUTH_INFO_REQUEST.
6537 * Display header data, and start going through
6538 * the prompts.
6539 */
6540 char *name, *inst, *lang;
6541 int name_len, inst_len, lang_len;
6542
ff3187f6 6543 ssh_pkt_getstring(pktin, &name, &name_len);
6544 ssh_pkt_getstring(pktin, &inst, &inst_len);
6545 ssh_pkt_getstring(pktin, &lang, &lang_len);
45068b27 6546 if (name_len > 0) {
51470298 6547 c_write_untrusted(ssh, name, name_len);
6548 c_write_str(ssh, "\r\n");
45068b27 6549 }
6550 if (inst_len > 0) {
51470298 6551 c_write_untrusted(ssh, inst, inst_len);
6552 c_write_str(ssh, "\r\n");
45068b27 6553 }
ff3187f6 6554 s->num_prompts = ssh_pkt_getuint32(pktin);
45068b27 6555 }
af659722 6556
45068b27 6557 /*
6558 * If there are prompts remaining in the packet,
6559 * display one and get a response.
6560 */
51470298 6561 if (s->curr_prompt < s->num_prompts) {
45068b27 6562 char *prompt;
6563 int prompt_len;
af659722 6564
ff3187f6 6565 ssh_pkt_getstring(pktin, &prompt, &prompt_len);
45068b27 6566 if (prompt_len > 0) {
85fdbe25 6567 static const char trunc[] = "<prompt truncated>: ";
6568 static const int prlen = sizeof(s->pwprompt) -
6569 lenof(trunc);
6570 if (prompt_len > prlen) {
6571 memcpy(s->pwprompt, prompt, prlen);
6572 strcpy(s->pwprompt + prlen, trunc);
6573 } else {
6574 memcpy(s->pwprompt, prompt, prompt_len);
6575 s->pwprompt[prompt_len] = '\0';
6576 }
45068b27 6577 } else {
51470298 6578 strcpy(s->pwprompt,
45068b27 6579 "<server failed to send prompt>: ");
6580 }
ff3187f6 6581 s->echo = ssh2_pkt_getbool(pktin);
51470298 6582 s->need_pw = TRUE;
45068b27 6583 } else
51470298 6584 s->need_pw = FALSE;
af659722 6585 }
6586
51470298 6587 if (!s->method && s->can_passwd) {
6588 s->method = AUTH_PASSWORD;
6589 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6590 ssh->pkt_ctx |= SSH2_PKTCTX_PASSWORD;
6591 sprintf(s->pwprompt, "%.90s@%.90s's password: ", s->username,
6592 ssh->savedhost);
6593 s->need_pw = TRUE;
1408a877 6594 }
6595
51470298 6596 if (s->need_pw) {
fa17a66e 6597 if (ssh_get_line) {
51470298 6598 if (!ssh_get_line(s->pwprompt, s->password,
6599 sizeof(s->password), TRUE)) {
1408a877 6600 /*
fa17a66e 6601 * get_line failed to get a password (for
6602 * example because one was supplied on the
6603 * command line which has already failed to
6604 * work). Terminate.
1408a877 6605 */
ff3187f6 6606 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
6607 ssh2_pkt_adduint32(s->pktout,SSH2_DISCONNECT_BY_APPLICATION);
6608 ssh2_pkt_addstring(s->pktout, "No more passwords available"
51470298 6609 " to try");
ff3187f6 6610 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
590f6a5f 6611 ssh2_pkt_send_noqueue(ssh, s->pktout);
247308b5 6612 logevent("Unable to authenticate");
a8327734 6613 connection_fatal(ssh->frontend,
6614 "Unable to authenticate");
3bb2f322 6615 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 6616 crStopV;
1408a877 6617 }
6618 } else {
51470298 6619 int ret; /* need not be saved across crReturn */
6620 c_write_untrusted(ssh, s->pwprompt, strlen(s->pwprompt));
6621 ssh->send_ok = 1;
1408a877 6622
51470298 6623 setup_userpass_input(ssh, s->password,
6624 sizeof(s->password), s->echo);
0405e71f 6625 do {
ff3187f6 6626 crWaitUntilV(!pktin);
51470298 6627 ret = process_userpass_input(ssh, in, inlen);
0405e71f 6628 } while (ret == 0);
6629 if (ret < 0)
6630 cleanup_exit(0);
51470298 6631 c_write_str(ssh, "\r\n");
65a22376 6632 }
65a22376 6633 }
65a22376 6634
51470298 6635 if (s->method == AUTH_PUBLICKEY_FILE) {
1408a877 6636 /*
6637 * We have our passphrase. Now try the actual authentication.
6638 */
6639 struct ssh2_userkey *key;
222d54dc 6640 const char *error = NULL;
65a22376 6641
222d54dc 6642 key = ssh2_load_userkey(&ssh->cfg.keyfile, s->password,
6643 &error);
1408a877 6644 if (key == SSH2_WRONG_PASSPHRASE || key == NULL) {
6645 if (key == SSH2_WRONG_PASSPHRASE) {
51470298 6646 c_write_str(ssh, "Wrong passphrase\r\n");
6647 s->tried_pubkey_config = FALSE;
1408a877 6648 } else {
222d54dc 6649 c_write_str(ssh, "Unable to load private key (");
6650 c_write_str(ssh, error);
6651 c_write_str(ssh, ")\r\n");
51470298 6652 s->tried_pubkey_config = TRUE;
1408a877 6653 }
6654 /* Send a spurious AUTH_NONE to return to the top. */
ff3187f6 6655 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6656 ssh2_pkt_addstring(s->pktout, s->username);
6657 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6658 ssh2_pkt_addstring(s->pktout, "none"); /* method */
6659 ssh2_pkt_send(ssh, s->pktout);
51470298 6660 s->type = AUTH_TYPE_NONE;
1408a877 6661 } else {
1dd353b5 6662 unsigned char *pkblob, *sigblob, *sigdata;
6663 int pkblob_len, sigblob_len, sigdata_len;
dda87a28 6664 int p;
65a22376 6665
1408a877 6666 /*
6667 * We have loaded the private key and the server
6668 * has announced that it's willing to accept it.
6669 * Hallelujah. Generate a signature and send it.
6670 */
ff3187f6 6671 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6672 ssh2_pkt_addstring(s->pktout, s->username);
6673 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6674 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6675 ssh2_pkt_addbool(s->pktout, TRUE);
6676 ssh2_pkt_addstring(s->pktout, key->alg->name);
1dd353b5 6677 pkblob = key->alg->public_blob(key->data, &pkblob_len);
ff3187f6 6678 ssh2_pkt_addstring_start(s->pktout);
6679 ssh2_pkt_addstring_data(s->pktout, (char *)pkblob, pkblob_len);
1408a877 6680
6681 /*
6682 * The data to be signed is:
6683 *
6684 * string session-id
6685 *
6686 * followed by everything so far placed in the
6687 * outgoing packet.
6688 */
ff3187f6 6689 sigdata_len = s->pktout->length - 5 + 4 + 20;
dda87a28 6690 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
6691 sigdata_len -= 4;
92d60585 6692 sigdata = snewn(sigdata_len, unsigned char);
dda87a28 6693 p = 0;
6694 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
6695 PUT_32BIT(sigdata+p, 20);
6696 p += 4;
6697 }
6698 memcpy(sigdata+p, ssh->v2_session_id, 20); p += 20;
ff3187f6 6699 memcpy(sigdata+p, s->pktout->data + 5,
6700 s->pktout->length - 5);
6701 p += s->pktout->length - 5;
dda87a28 6702 assert(p == sigdata_len);
d8baa528 6703 sigblob = key->alg->sign(key->data, (char *)sigdata,
1dd353b5 6704 sigdata_len, &sigblob_len);
ff3187f6 6705 ssh2_add_sigblob(ssh, s->pktout, pkblob, pkblob_len,
1dd353b5 6706 sigblob, sigblob_len);
6707 sfree(pkblob);
6708 sfree(sigblob);
1408a877 6709 sfree(sigdata);
6710
ff3187f6 6711 ssh2_pkt_send(ssh, s->pktout);
51470298 6712 s->type = AUTH_TYPE_PUBLICKEY;
75374b2f 6713 key->alg->freekey(key->data);
1408a877 6714 }
51470298 6715 } else if (s->method == AUTH_PASSWORD) {
65a22376 6716 /*
1408a877 6717 * We send the password packet lumped tightly together with
6718 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
6719 * string long enough to make the total length of the two
6720 * packets constant. This should ensure that a passive
6721 * listener doing traffic analyis can't work out the length
6722 * of the password.
6723 *
6724 * For this to work, we need an assumption about the
6725 * maximum length of the password packet. I think 256 is
6726 * pretty conservative. Anyone using a password longer than
6727 * that probably doesn't have much to worry about from
6728 * people who find out how long their password is!
65a22376 6729 */
ff3187f6 6730 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6731 ssh2_pkt_addstring(s->pktout, s->username);
6732 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6733 ssh2_pkt_addstring(s->pktout, "password");
6734 ssh2_pkt_addbool(s->pktout, FALSE);
6735 dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
6736 ssh2_pkt_addstring(s->pktout, s->password);
1409c1b3 6737 memset(s->password, 0, sizeof(s->password));
ff3187f6 6738 end_log_omission(ssh, s->pktout);
6739 ssh2_pkt_defer(ssh, s->pktout);
65a22376 6740 /*
1408a877 6741 * We'll include a string that's an exact multiple of the
6742 * cipher block size. If the cipher is NULL for some
6743 * reason, we don't do this trick at all because we gain
6744 * nothing by it.
65a22376 6745 */
51470298 6746 if (ssh->cscipher) {
32874aea 6747 int stringlen, i;
6748
51470298 6749 stringlen = (256 - ssh->deferred_len);
6750 stringlen += ssh->cscipher->blksize - 1;
6751 stringlen -= (stringlen % ssh->cscipher->blksize);
6752 if (ssh->cscomp) {
32874aea 6753 /*
6754 * Temporarily disable actual compression,
6755 * so we can guarantee to get this string
6756 * exactly the length we want it. The
6757 * compression-disabling routine should
6758 * return an integer indicating how many
6759 * bytes we should adjust our string length
6760 * by.
6761 */
5366aed8 6762 stringlen -=
6763 ssh->cscomp->disable_compression(ssh->cs_comp_ctx);
32874aea 6764 }
ff3187f6 6765 s->pktout = ssh2_pkt_init(SSH2_MSG_IGNORE);
6766 ssh2_pkt_addstring_start(s->pktout);
6e9e9520 6767 for (i = 0; i < stringlen; i++) {
32874aea 6768 char c = (char) random_byte();
ff3187f6 6769 ssh2_pkt_addstring_data(s->pktout, &c, 1);
65a22376 6770 }
ff3187f6 6771 ssh2_pkt_defer(ssh, s->pktout);
65a22376 6772 }
51470298 6773 ssh_pkt_defersend(ssh);
0d43337a 6774 logevent("Sent password");
51470298 6775 s->type = AUTH_TYPE_PASSWORD;
6776 } else if (s->method == AUTH_KEYBOARD_INTERACTIVE) {
6777 if (s->curr_prompt == 0) {
ff3187f6 6778 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE);
6779 ssh2_pkt_adduint32(s->pktout, s->num_prompts);
45068b27 6780 }
51470298 6781 if (s->need_pw) { /* only add pw if we just got one! */
ff3187f6 6782 dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
6783 ssh2_pkt_addstring(s->pktout, s->password);
51470298 6784 memset(s->password, 0, sizeof(s->password));
ff3187f6 6785 end_log_omission(ssh, s->pktout);
51470298 6786 s->curr_prompt++;
45068b27 6787 }
51470298 6788 if (s->curr_prompt >= s->num_prompts) {
ff3187f6 6789 ssh2_pkt_send(ssh, s->pktout);
45068b27 6790 } else {
6791 /*
6792 * If there are prompts remaining, we set
6793 * `gotit' so that we won't attempt to get
6794 * another packet. Then we go back round the
6795 * loop and will end up retrieving another
6796 * prompt out of the existing packet. Funky or
6797 * what?
6798 */
51470298 6799 s->gotit = TRUE;
45068b27 6800 }
51470298 6801 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
1408a877 6802 } else {
51470298 6803 c_write_str(ssh, "No supported authentication methods"
6804 " left to try!\r\n");
6805 logevent("No supported authentications offered."
6806 " Disconnecting");
ff3187f6 6807 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
6808 ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
6809 ssh2_pkt_addstring(s->pktout, "No supported authentication"
51470298 6810 " methods available");
ff3187f6 6811 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
590f6a5f 6812 ssh2_pkt_send_noqueue(ssh, s->pktout);
3bb2f322 6813 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 6814 crStopV;
65a22376 6815 }
65a22376 6816 }
51470298 6817 } while (!s->we_are_in);
7cca0d81 6818
6819 /*
6820 * Now we're authenticated for the connection protocol. The
6821 * connection protocol will automatically have started at this
6822 * point; there's no need to send SERVICE_REQUEST.
6823 */
6824
0ed48730 6825 ssh->channels = newtree234(ssh_channelcmp);
6826
7cca0d81 6827 /*
b09eaa88 6828 * Set up handlers for some connection protocol messages, so we
6829 * don't have to handle them repeatedly in this coroutine.
6830 */
6831 ssh->packet_dispatch[SSH2_MSG_CHANNEL_WINDOW_ADJUST] =
6832 ssh2_msg_channel_window_adjust;
51df0ab5 6833 ssh->packet_dispatch[SSH2_MSG_GLOBAL_REQUEST] =
6834 ssh2_msg_global_request;
b09eaa88 6835
6836 /*
0ed48730 6837 * Create the main session channel.
7cca0d81 6838 */
0ed48730 6839 if (!ssh->cfg.ssh_no_shell) {
6840 ssh->mainchan = snew(struct ssh_channel);
6841 ssh->mainchan->ssh = ssh;
6842 ssh->mainchan->localid = alloc_channel_id(ssh);
ff3187f6 6843 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
6844 ssh2_pkt_addstring(s->pktout, "session");
6845 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->localid);
0ed48730 6846 ssh->mainchan->v.v2.locwindow = OUR_V2_WINSIZE;
ff3187f6 6847 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->v.v2.locwindow);/* our window size */
6848 ssh2_pkt_adduint32(s->pktout, 0x4000UL); /* our max pkt size */
6849 ssh2_pkt_send(ssh, s->pktout);
6850 crWaitUntilV(pktin);
6851 if (pktin->type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
0ed48730 6852 bombout(("Server refused to open a session"));
6853 crStopV;
6854 /* FIXME: error data comes back in FAILURE packet */
6855 }
ff3187f6 6856 if (ssh_pkt_getuint32(pktin) != ssh->mainchan->localid) {
0ed48730 6857 bombout(("Server's channel confirmation cited wrong channel"));
6858 crStopV;
6859 }
ff3187f6 6860 ssh->mainchan->remoteid = ssh_pkt_getuint32(pktin);
0ed48730 6861 ssh->mainchan->type = CHAN_MAINSESSION;
6862 ssh->mainchan->closes = 0;
ff3187f6 6863 ssh->mainchan->v.v2.remwindow = ssh_pkt_getuint32(pktin);
6864 ssh->mainchan->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin);
0ed48730 6865 bufchain_init(&ssh->mainchan->v.v2.outbuffer);
6866 add234(ssh->channels, ssh->mainchan);
62638676 6867 update_specials_menu(ssh->frontend);
0ed48730 6868 logevent("Opened channel for session");
6869 } else
6870 ssh->mainchan = NULL;
7cca0d81 6871
6872 /*
51df0ab5 6873 * Now we have a channel, make dispatch table entries for
6874 * general channel-based messages.
6875 */
6876 ssh->packet_dispatch[SSH2_MSG_CHANNEL_DATA] =
6877 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EXTENDED_DATA] =
6878 ssh2_msg_channel_data;
6879 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EOF] = ssh2_msg_channel_eof;
6880 ssh->packet_dispatch[SSH2_MSG_CHANNEL_CLOSE] = ssh2_msg_channel_close;
6881 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION] =
6882 ssh2_msg_channel_open_confirmation;
6883 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_FAILURE] =
6884 ssh2_msg_channel_open_failure;
6885 ssh->packet_dispatch[SSH2_MSG_CHANNEL_REQUEST] =
6886 ssh2_msg_channel_request;
6887 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN] =
6888 ssh2_msg_channel_open;
6889
6890 /*
783415f8 6891 * Potentially enable X11 forwarding.
6892 */
0ed48730 6893 if (ssh->mainchan && ssh->cfg.x11_forward) {
32874aea 6894 char proto[20], data[64];
6895 logevent("Requesting X11 forwarding");
302121de 6896 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
86916870 6897 data, sizeof(data), ssh->cfg.x11_auth);
6898 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
ff3187f6 6899 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
6900 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
6901 ssh2_pkt_addstring(s->pktout, "x11-req");
6902 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
6903 ssh2_pkt_addbool(s->pktout, 0); /* many connections */
6904 ssh2_pkt_addstring(s->pktout, proto);
6905 ssh2_pkt_addstring(s->pktout, data);
6906 ssh2_pkt_adduint32(s->pktout, x11_get_screen_number(ssh->cfg.x11_display));
6907 ssh2_pkt_send(ssh, s->pktout);
32874aea 6908
b09eaa88 6909 crWaitUntilV(pktin);
32874aea 6910
ff3187f6 6911 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
6912 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 6913 bombout(("Unexpected response to X11 forwarding request:"
ff3187f6 6914 " packet type %d", pktin->type));
7ffdbc1a 6915 crStopV;
32874aea 6916 }
6917 logevent("X11 forwarding refused");
6918 } else {
6919 logevent("X11 forwarding enabled");
51470298 6920 ssh->X11_fwd_enabled = TRUE;
32874aea 6921 }
783415f8 6922 }
6923
6924 /*
bc240b21 6925 * Enable port forwardings.
6926 */
06fadff5 6927 ssh_setup_portfwd(ssh, &ssh->cfg);
bc240b21 6928
6929 /*
36c2a3e9 6930 * Potentially enable agent forwarding.
6931 */
0ed48730 6932 if (ssh->mainchan && ssh->cfg.agentfwd && agent_exists()) {
32874aea 6933 logevent("Requesting OpenSSH-style agent forwarding");
ff3187f6 6934 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
6935 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
6936 ssh2_pkt_addstring(s->pktout, "auth-agent-req@openssh.com");
6937 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
6938 ssh2_pkt_send(ssh, s->pktout);
32874aea 6939
b09eaa88 6940 crWaitUntilV(pktin);
32874aea 6941
ff3187f6 6942 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
6943 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 6944 bombout(("Unexpected response to agent forwarding request:"
ff3187f6 6945 " packet type %d", pktin->type));
7ffdbc1a 6946 crStopV;
32874aea 6947 }
6948 logevent("Agent forwarding refused");
6949 } else {
6950 logevent("Agent forwarding enabled");
51470298 6951 ssh->agentfwd_enabled = TRUE;
32874aea 6952 }
36c2a3e9 6953 }
6954
6955 /*
7cca0d81 6956 * Now allocate a pty for the session.
6957 */
0ed48730 6958 if (ssh->mainchan && !ssh->cfg.nopty) {
a5dd8467 6959 /* Unpick the terminal-speed string. */
6960 /* XXX perhaps we should allow no speeds to be sent. */
db219738 6961 ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
6962 sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
a5dd8467 6963 /* Build the pty request. */
ff3187f6 6964 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
6965 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid); /* recipient channel */
6966 ssh2_pkt_addstring(s->pktout, "pty-req");
6967 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
6968 ssh2_pkt_addstring(s->pktout, ssh->cfg.termtype);
6969 ssh2_pkt_adduint32(s->pktout, ssh->term_width);
6970 ssh2_pkt_adduint32(s->pktout, ssh->term_height);
6971 ssh2_pkt_adduint32(s->pktout, 0); /* pixel width */
6972 ssh2_pkt_adduint32(s->pktout, 0); /* pixel height */
6973 ssh2_pkt_addstring_start(s->pktout);
6974 ssh2_pkt_addbyte(s->pktout, 128); /* TTY_OP_ISPEED */
6975 ssh2_pkt_adduint32(s->pktout, ssh->ispeed);
6976 ssh2_pkt_addbyte(s->pktout, 129); /* TTY_OP_OSPEED */
6977 ssh2_pkt_adduint32(s->pktout, ssh->ospeed);
6978 ssh2_pkt_addstring_data(s->pktout, "\0", 1); /* TTY_OP_END */
6979 ssh2_pkt_send(ssh, s->pktout);
51470298 6980 ssh->state = SSH_STATE_INTERMED;
32874aea 6981
b09eaa88 6982 crWaitUntilV(pktin);
32874aea 6983
ff3187f6 6984 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
6985 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 6986 bombout(("Unexpected response to pty request:"
ff3187f6 6987 " packet type %d", pktin->type));
7ffdbc1a 6988 crStopV;
32874aea 6989 }
51470298 6990 c_write_str(ssh, "Server refused to allocate pty\r\n");
6991 ssh->editing = ssh->echoing = 1;
32874aea 6992 } else {
a5dd8467 6993 logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
db219738 6994 ssh->ospeed, ssh->ispeed);
32874aea 6995 }
0965bee0 6996 } else {
51470298 6997 ssh->editing = ssh->echoing = 1;
7cca0d81 6998 }
6999
7000 /*
73feed4f 7001 * Send environment variables.
7002 *
7003 * Simplest thing here is to send all the requests at once, and
7004 * then wait for a whole bunch of successes or failures.
7005 */
7006 if (ssh->mainchan && *ssh->cfg.environmt) {
7007 char *e = ssh->cfg.environmt;
7008 char *var, *varend, *val;
7009
7010 s->num_env = 0;
7011
7012 while (*e) {
7013 var = e;
7014 while (*e && *e != '\t') e++;
7015 varend = e;
7016 if (*e == '\t') e++;
7017 val = e;
7018 while (*e) e++;
7019 e++;
7020
ff3187f6 7021 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7022 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
7023 ssh2_pkt_addstring(s->pktout, "env");
7024 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7025 ssh2_pkt_addstring_start(s->pktout);
7026 ssh2_pkt_addstring_data(s->pktout, var, varend-var);
7027 ssh2_pkt_addstring(s->pktout, val);
7028 ssh2_pkt_send(ssh, s->pktout);
73feed4f 7029
7030 s->num_env++;
7031 }
7032
7033 logeventf(ssh, "Sent %d environment variables", s->num_env);
7034
7035 s->env_ok = 0;
7036 s->env_left = s->num_env;
7037
7038 while (s->env_left > 0) {
b09eaa88 7039 crWaitUntilV(pktin);
73feed4f 7040
ff3187f6 7041 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
7042 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
73feed4f 7043 bombout(("Unexpected response to environment request:"
ff3187f6 7044 " packet type %d", pktin->type));
73feed4f 7045 crStopV;
7046 }
7047 } else {
7048 s->env_ok++;
7049 }
7050
7051 s->env_left--;
7052 }
7053
7054 if (s->env_ok == s->num_env) {
7055 logevent("All environment variables successfully set");
7056 } else if (s->env_ok == 0) {
7057 logevent("All environment variables refused");
7058 c_write_str(ssh, "Server refused to set environment variables\r\n");
7059 } else {
7060 logeventf(ssh, "%d environment variables refused",
7061 s->num_env - s->env_ok);
7062 c_write_str(ssh, "Server refused to set all environment variables\r\n");
7063 }
7064 }
7065
7066 /*
fd5e5847 7067 * Start a shell or a remote command. We may have to attempt
7068 * this twice if the config data has provided a second choice
7069 * of command.
7cca0d81 7070 */
0ed48730 7071 if (ssh->mainchan) while (1) {
fd5e5847 7072 int subsys;
7073 char *cmd;
7074
51470298 7075 if (ssh->fallback_cmd) {
86916870 7076 subsys = ssh->cfg.ssh_subsys2;
7077 cmd = ssh->cfg.remote_cmd_ptr2;
fd5e5847 7078 } else {
86916870 7079 subsys = ssh->cfg.ssh_subsys;
7080 cmd = ssh->cfg.remote_cmd_ptr;
fd5e5847 7081 }
7082
ff3187f6 7083 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7084 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid); /* recipient channel */
fd5e5847 7085 if (subsys) {
ff3187f6 7086 ssh2_pkt_addstring(s->pktout, "subsystem");
7087 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7088 ssh2_pkt_addstring(s->pktout, cmd);
fd5e5847 7089 } else if (*cmd) {
ff3187f6 7090 ssh2_pkt_addstring(s->pktout, "exec");
7091 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7092 ssh2_pkt_addstring(s->pktout, cmd);
fd5e5847 7093 } else {
ff3187f6 7094 ssh2_pkt_addstring(s->pktout, "shell");
7095 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
32874aea 7096 }
ff3187f6 7097 ssh2_pkt_send(ssh, s->pktout);
b09eaa88 7098
7099 crWaitUntilV(pktin);
7100
ff3187f6 7101 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
7102 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 7103 bombout(("Unexpected response to shell/command request:"
ff3187f6 7104 " packet type %d", pktin->type));
7ffdbc1a 7105 crStopV;
fd5e5847 7106 }
7107 /*
7108 * We failed to start the command. If this is the
7109 * fallback command, we really are finished; if it's
7110 * not, and if the fallback command exists, try falling
7111 * back to it before complaining.
7112 */
86916870 7113 if (!ssh->fallback_cmd && ssh->cfg.remote_cmd_ptr2 != NULL) {
fd5e5847 7114 logevent("Primary command failed; attempting fallback");
51470298 7115 ssh->fallback_cmd = TRUE;
fd5e5847 7116 continue;
7117 }
6b5cf8b4 7118 bombout(("Server refused to start a shell/command"));
7ffdbc1a 7119 crStopV;
fd5e5847 7120 } else {
7121 logevent("Started a shell/command");
32874aea 7122 }
fd5e5847 7123 break;
7cca0d81 7124 }
7125
51470298 7126 ssh->state = SSH_STATE_SESSION;
7127 if (ssh->size_needed)
7128 ssh_size(ssh, ssh->term_width, ssh->term_height);
7129 if (ssh->eof_needed)
7130 ssh_special(ssh, TS_EOF);
6e48c3fe 7131
7cca0d81 7132 /*
7133 * Transfer data!
7134 */
b9d7bcad 7135 if (ssh->ldisc)
7136 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
0ed48730 7137 if (ssh->mainchan)
7138 ssh->send_ok = 1;
7cca0d81 7139 while (1) {
e5574168 7140 crReturnV;
51470298 7141 s->try_send = FALSE;
ff3187f6 7142 if (pktin) {
2b7540a7 7143
51df0ab5 7144 /*
7145 * _All_ the connection-layer packets we expect to
7146 * receive are now handled by the dispatch table.
7147 * Anything that reaches here must be bogus.
7148 */
32874aea 7149
51df0ab5 7150 bombout(("Strange packet received: type %d", pktin->type));
7151 crStopV;
0ed48730 7152 } else if (ssh->mainchan) {
32874aea 7153 /*
7154 * We have spare data. Add it to the channel buffer.
7155 */
d8baa528 7156 ssh2_add_channel_data(ssh->mainchan, (char *)in, inlen);
51470298 7157 s->try_send = TRUE;
32874aea 7158 }
51470298 7159 if (s->try_send) {
32874aea 7160 int i;
7161 struct ssh_channel *c;
7162 /*
7163 * Try to send data on all channels if we can.
7164 */
51470298 7165 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
a6253970 7166 int bufsize;
7167 if (c->closes)
7168 continue; /* don't send on closing channels */
7169 bufsize = ssh2_try_send(c);
5471d09a 7170 if (bufsize == 0) {
7171 switch (c->type) {
7172 case CHAN_MAINSESSION:
7173 /* stdin need not receive an unthrottle
7174 * notification since it will be polled */
7175 break;
7176 case CHAN_X11:
7177 x11_unthrottle(c->u.x11.s);
7178 break;
7179 case CHAN_AGENT:
7180 /* agent sockets are request/response and need no
7181 * buffer management */
7182 break;
7183 case CHAN_SOCKDATA:
7184 pfd_unthrottle(c->u.pfd.s);
7185 break;
7186 }
7187 }
7188 }
7cca0d81 7189 }
e5574168 7190 }
7191
7192 crFinishV;
7193}
7194
7195/*
b09eaa88 7196 * Handlers for SSH2 messages that might arrive at any moment.
7197 */
7198void ssh2_msg_disconnect(Ssh ssh, struct Packet *pktin)
7199{
7200 /* log reason code in disconnect message */
7201 char *buf, *msg;
7202 int nowlen, reason, msglen;
7203
7204 reason = ssh_pkt_getuint32(pktin);
7205 ssh_pkt_getstring(pktin, &msg, &msglen);
7206
7207 if (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) {
7208 buf = dupprintf("Received disconnect message (%s)",
7209 ssh2_disconnect_reasons[reason]);
7210 } else {
7211 buf = dupprintf("Received disconnect message (unknown"
7212 " type %d)", reason);
7213 }
7214 logevent(buf);
7215 sfree(buf);
7216 buf = dupprintf("Disconnection message text: %n%.*s",
7217 &nowlen, msglen, msg);
7218 logevent(buf);
7219 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
7220 reason,
7221 (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) ?
7222 ssh2_disconnect_reasons[reason] : "unknown",
7223 buf+nowlen));
7224 sfree(buf);
7225}
7226
7227void ssh2_msg_debug(Ssh ssh, struct Packet *pktin)
7228{
7229 /* log the debug message */
7230 char *buf, *msg;
7231 int msglen;
7232 int always_display;
7233
7234 /* XXX maybe we should actually take notice of this */
7235 always_display = ssh2_pkt_getbool(pktin);
7236 ssh_pkt_getstring(pktin, &msg, &msglen);
7237
7238 buf = dupprintf("Remote debug message: %.*s", msglen, msg);
7239 logevent(buf);
7240 sfree(buf);
7241}
7242
7243void ssh2_msg_something_unimplemented(Ssh ssh, struct Packet *pktin)
7244{
7245 struct Packet *pktout;
7246 pktout = ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED);
7247 ssh2_pkt_adduint32(pktout, pktin->sequence);
7248 /*
7249 * UNIMPLEMENTED messages MUST appear in the same order as the
7250 * messages they respond to. Hence, never queue them.
7251 */
7252 ssh2_pkt_send_noqueue(ssh, pktout);
7253}
7254
7255/*
7cca0d81 7256 * Handle the top-level SSH2 protocol.
7257 */
b09eaa88 7258static void ssh2_protocol_setup(Ssh ssh)
7259{
7260 int i;
7261
7262 /*
7263 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
7264 */
7265 for (i = 0; i < 256; i++)
7266 ssh->packet_dispatch[i] = ssh2_msg_something_unimplemented;
7267
7268 /*
7269 * Any message we actually understand, we set to NULL so that
7270 * the coroutines will get it.
7271 */
7272 ssh->packet_dispatch[SSH2_MSG_UNIMPLEMENTED] = NULL;
7273 ssh->packet_dispatch[SSH2_MSG_SERVICE_REQUEST] = NULL;
7274 ssh->packet_dispatch[SSH2_MSG_SERVICE_ACCEPT] = NULL;
7275 ssh->packet_dispatch[SSH2_MSG_KEXINIT] = NULL;
7276 ssh->packet_dispatch[SSH2_MSG_NEWKEYS] = NULL;
7277 ssh->packet_dispatch[SSH2_MSG_KEXDH_INIT] = NULL;
7278 ssh->packet_dispatch[SSH2_MSG_KEXDH_REPLY] = NULL;
7279 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
7280 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
7281 ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_INIT] = NULL;
7282 ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REPLY] = NULL;
7283 ssh->packet_dispatch[SSH2_MSG_USERAUTH_REQUEST] = NULL;
7284 ssh->packet_dispatch[SSH2_MSG_USERAUTH_FAILURE] = NULL;
7285 ssh->packet_dispatch[SSH2_MSG_USERAUTH_SUCCESS] = NULL;
7286 ssh->packet_dispatch[SSH2_MSG_USERAUTH_BANNER] = NULL;
7287 ssh->packet_dispatch[SSH2_MSG_USERAUTH_PK_OK] = NULL;
7288 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
7289 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
7290 ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_RESPONSE] = NULL;
7291 ssh->packet_dispatch[SSH2_MSG_GLOBAL_REQUEST] = NULL;
7292 ssh->packet_dispatch[SSH2_MSG_REQUEST_SUCCESS] = NULL;
7293 ssh->packet_dispatch[SSH2_MSG_REQUEST_FAILURE] = NULL;
7294 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN] = NULL;
7295 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION] = NULL;
7296 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_FAILURE] = NULL;
7297 ssh->packet_dispatch[SSH2_MSG_CHANNEL_WINDOW_ADJUST] = NULL;
7298 ssh->packet_dispatch[SSH2_MSG_CHANNEL_DATA] = NULL;
7299 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EXTENDED_DATA] = NULL;
7300 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EOF] = NULL;
7301 ssh->packet_dispatch[SSH2_MSG_CHANNEL_CLOSE] = NULL;
7302 ssh->packet_dispatch[SSH2_MSG_CHANNEL_REQUEST] = NULL;
7303 ssh->packet_dispatch[SSH2_MSG_CHANNEL_SUCCESS] = NULL;
7304 ssh->packet_dispatch[SSH2_MSG_CHANNEL_FAILURE] = NULL;
7305
7306 /*
7307 * These special message types we install handlers for.
7308 */
7309 ssh->packet_dispatch[SSH2_MSG_DISCONNECT] = ssh2_msg_disconnect;
7310 ssh->packet_dispatch[SSH2_MSG_IGNORE] = ssh_msg_ignore; /* shared with ssh1 */
7311 ssh->packet_dispatch[SSH2_MSG_DEBUG] = ssh2_msg_debug;
7312}
7313
9442dd57 7314static void ssh2_timer(void *ctx, long now)
7315{
7316 Ssh ssh = (Ssh)ctx;
7317
e6c1536e 7318 if (!ssh->kex_in_progress && ssh->cfg.ssh_rekey_time != 0 &&
9442dd57 7319 now - ssh->next_rekey >= 0) {
f382c87d 7320 do_ssh2_transport(ssh, "timeout", -1, NULL);
9442dd57 7321 }
7322}
7323
ff3187f6 7324static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen,
7325 struct Packet *pktin)
7cca0d81 7326{
b09eaa88 7327 if (ssh->state == SSH_STATE_CLOSED)
7328 return;
7329
9442dd57 7330 if (pktin) {
7331 ssh->incoming_data_size += pktin->encrypted_len;
7332 if (!ssh->kex_in_progress &&
d57f70af 7333 ssh->max_data_size != 0 &&
7334 ssh->incoming_data_size > ssh->max_data_size)
f382c87d 7335 do_ssh2_transport(ssh, "too much data received", -1, NULL);
9442dd57 7336 }
7337
b09eaa88 7338 if (pktin && ssh->packet_dispatch[pktin->type]) {
7339 ssh->packet_dispatch[pktin->type](ssh, pktin);
32874aea 7340 return;
b09eaa88 7341 }
7342
7343 if (!ssh->protocol_initial_phase_done ||
7344 (pktin && pktin->type >= 20 && pktin->type < 50)) {
7345 if (do_ssh2_transport(ssh, in, inlen, pktin) &&
7346 !ssh->protocol_initial_phase_done) {
7347 ssh->protocol_initial_phase_done = TRUE;
7348 /*
7349 * Allow authconn to initialise itself.
7350 */
7351 do_ssh2_authconn(ssh, NULL, 0, NULL);
7352 }
7353 } else {
7354 do_ssh2_authconn(ssh, in, inlen, pktin);
7355 }
7cca0d81 7356}
7357
7358/*
8df7a775 7359 * Called to set up the connection.
374330e2 7360 *
7361 * Returns an error message, or NULL on success.
374330e2 7362 */
cbe2d68f 7363static const char *ssh_init(void *frontend_handle, void **backend_handle,
7364 Config *cfg,
79bf227b 7365 char *host, int port, char **realhost, int nodelay,
7366 int keepalive)
32874aea 7367{
cbe2d68f 7368 const char *p;
51470298 7369 Ssh ssh;
7370
3d88e64d 7371 ssh = snew(struct ssh_tag);
86916870 7372 ssh->cfg = *cfg; /* STRUCTURE COPY */
125105d1 7373 ssh->version = 0; /* when not ready yet */
51470298 7374 ssh->s = NULL;
7375 ssh->cipher = NULL;
371e569c 7376 ssh->v1_cipher_ctx = NULL;
0183b242 7377 ssh->crcda_ctx = NULL;
51470298 7378 ssh->cscipher = NULL;
371e569c 7379 ssh->cs_cipher_ctx = NULL;
51470298 7380 ssh->sccipher = NULL;
371e569c 7381 ssh->sc_cipher_ctx = NULL;
51470298 7382 ssh->csmac = NULL;
a8327734 7383 ssh->cs_mac_ctx = NULL;
51470298 7384 ssh->scmac = NULL;
e0e1a00d 7385 ssh->sc_mac_ctx = NULL;
51470298 7386 ssh->cscomp = NULL;
5366aed8 7387 ssh->cs_comp_ctx = NULL;
51470298 7388 ssh->sccomp = NULL;
5366aed8 7389 ssh->sc_comp_ctx = NULL;
51470298 7390 ssh->kex = NULL;
389aa499 7391 ssh->kex_ctx = NULL;
51470298 7392 ssh->hostkey = NULL;
7393 ssh->exitcode = -1;
7394 ssh->state = SSH_STATE_PREPACKET;
7395 ssh->size_needed = FALSE;
7396 ssh->eof_needed = FALSE;
b9d7bcad 7397 ssh->ldisc = NULL;
a8327734 7398 ssh->logctx = NULL;
51470298 7399 ssh->deferred_send_data = NULL;
7400 ssh->deferred_len = 0;
7401 ssh->deferred_size = 0;
7402 ssh->fallback_cmd = 0;
7403 ssh->pkt_ctx = 0;
302121de 7404 ssh->x11auth = NULL;
be738459 7405 ssh->v1_compressing = FALSE;
51470298 7406 ssh->v2_outgoing_sequence = 0;
7407 ssh->ssh1_rdpkt_crstate = 0;
7408 ssh->ssh2_rdpkt_crstate = 0;
7409 ssh->do_ssh_init_crstate = 0;
7410 ssh->ssh_gotdata_crstate = 0;
b09eaa88 7411 ssh->do_ssh1_connection_crstate = 0;
51470298 7412 ssh->do_ssh1_login_crstate = 0;
7413 ssh->do_ssh2_transport_crstate = 0;
7414 ssh->do_ssh2_authconn_crstate = 0;
7415 ssh->do_ssh_init_state = NULL;
7416 ssh->do_ssh1_login_state = NULL;
7417 ssh->do_ssh2_transport_state = NULL;
7418 ssh->do_ssh2_authconn_state = NULL;
6571dbfd 7419 ssh->mainchan = NULL;
968d2d92 7420 ssh->throttled_all = 0;
7421 ssh->v1_stdout_throttling = 0;
590f6a5f 7422 ssh->queue = NULL;
7423 ssh->queuelen = ssh->queuesize = 0;
7424 ssh->queueing = FALSE;
06fadff5 7425 ssh->qhead = ssh->qtail = NULL;
e13bba36 7426 ssh->deferred_rekey_reason = NULL;
51470298 7427
7428 *backend_handle = ssh;
32874aea 7429
8f203108 7430#ifdef MSCRYPTOAPI
32874aea 7431 if (crypto_startup() == 0)
8f203108 7432 return "Microsoft high encryption pack not installed!";
7433#endif
374330e2 7434
51470298 7435 ssh->frontend = frontend_handle;
86916870 7436 ssh->term_width = ssh->cfg.width;
7437 ssh->term_height = ssh->cfg.height;
887035a5 7438
fabd1805 7439 ssh->channels = NULL;
7440 ssh->rportfwds = NULL;
f47a5ffb 7441 ssh->portfwds = NULL;
fabd1805 7442
51470298 7443 ssh->send_ok = 0;
7444 ssh->editing = 0;
7445 ssh->echoing = 0;
7446 ssh->v1_throttle_count = 0;
7447 ssh->overall_bufsize = 0;
7448 ssh->fallback_cmd = 0;
8df7a775 7449
3648d4c5 7450 ssh->protocol = NULL;
7451
b09eaa88 7452 ssh->protocol_initial_phase_done = FALSE;
7453
39934deb 7454 ssh->pinger = NULL;
7455
9442dd57 7456 ssh->incoming_data_size = ssh->outgoing_data_size =
7457 ssh->deferred_data_size = 0L;
d57f70af 7458 ssh->max_data_size = parse_blocksize(ssh->cfg.ssh_rekey_data);
9442dd57 7459 ssh->kex_in_progress = FALSE;
7460
79bf227b 7461 p = connect_to_host(ssh, host, port, realhost, nodelay, keepalive);
fb09bf1c 7462 if (p != NULL)
7463 return p;
374330e2 7464
5d17ccfc 7465 random_ref();
7466
374330e2 7467 return NULL;
7468}
7469
fabd1805 7470static void ssh_free(void *handle)
7471{
7472 Ssh ssh = (Ssh) handle;
7473 struct ssh_channel *c;
7474 struct ssh_rportfwd *pf;
7475
7476 if (ssh->v1_cipher_ctx)
7477 ssh->cipher->free_context(ssh->v1_cipher_ctx);
7478 if (ssh->cs_cipher_ctx)
7479 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
7480 if (ssh->sc_cipher_ctx)
7481 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
7482 if (ssh->cs_mac_ctx)
7483 ssh->csmac->free_context(ssh->cs_mac_ctx);
7484 if (ssh->sc_mac_ctx)
7485 ssh->scmac->free_context(ssh->sc_mac_ctx);
29b1d0b3 7486 if (ssh->cs_comp_ctx) {
7487 if (ssh->cscomp)
7488 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
7489 else
7490 zlib_compress_cleanup(ssh->cs_comp_ctx);
7491 }
7492 if (ssh->sc_comp_ctx) {
7493 if (ssh->sccomp)
7494 ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
7495 else
7496 zlib_decompress_cleanup(ssh->sc_comp_ctx);
7497 }
fabd1805 7498 if (ssh->kex_ctx)
7499 dh_cleanup(ssh->kex_ctx);
7500 sfree(ssh->savedhost);
7501
590f6a5f 7502 while (ssh->queuelen-- > 0)
7503 ssh_free_packet(ssh->queue[ssh->queuelen]);
7504 sfree(ssh->queue);
7505
06fadff5 7506 while (ssh->qhead) {
7507 struct queued_handler *qh = ssh->qhead;
7508 ssh->qhead = qh->next;
7509 sfree(ssh->qhead);
7510 }
7511 ssh->qhead = ssh->qtail = NULL;
7512
fabd1805 7513 if (ssh->channels) {
7514 while ((c = delpos234(ssh->channels, 0)) != NULL) {
7515 switch (c->type) {
7516 case CHAN_X11:
7517 if (c->u.x11.s != NULL)
7518 x11_close(c->u.x11.s);
7519 break;
7520 case CHAN_SOCKDATA:
7521 if (c->u.pfd.s != NULL)
7522 pfd_close(c->u.pfd.s);
7523 break;
7524 }
7525 sfree(c);
7526 }
7527 freetree234(ssh->channels);
cdb52705 7528 ssh->channels = NULL;
fabd1805 7529 }
7530
7531 if (ssh->rportfwds) {
7532 while ((pf = delpos234(ssh->rportfwds, 0)) != NULL)
7533 sfree(pf);
7534 freetree234(ssh->rportfwds);
cdb52705 7535 ssh->rportfwds = NULL;
fabd1805 7536 }
7537 sfree(ssh->deferred_send_data);
7538 if (ssh->x11auth)
7539 x11_free_auth(ssh->x11auth);
7540 sfree(ssh->do_ssh_init_state);
7541 sfree(ssh->do_ssh1_login_state);
7542 sfree(ssh->do_ssh2_transport_state);
7543 sfree(ssh->do_ssh2_authconn_state);
679539d7 7544 if (ssh->crcda_ctx) {
7545 crcda_free_context(ssh->crcda_ctx);
7546 ssh->crcda_ctx = NULL;
7547 }
fabd1805 7548 if (ssh->s)
36f94d1f 7549 ssh_do_close(ssh);
9442dd57 7550 expire_timer_context(ssh);
39934deb 7551 if (ssh->pinger)
7552 pinger_free(ssh->pinger);
ee50e8b6 7553 sfree(ssh);
5d17ccfc 7554
7555 random_unref();
fabd1805 7556}
7557
374330e2 7558/*
86916870 7559 * Reconfigure the SSH backend.
86916870 7560 */
7561static void ssh_reconfig(void *handle, Config *cfg)
7562{
7563 Ssh ssh = (Ssh) handle;
e13bba36 7564 char *rekeying = NULL, rekey_mandatory = FALSE;
e6c1536e 7565 unsigned long old_max_data_size;
7566
39934deb 7567 pinger_reconfig(ssh->pinger, &ssh->cfg, cfg);
fda2feb1 7568 ssh_setup_portfwd(ssh, cfg);
e6c1536e 7569
7570 if (ssh->cfg.ssh_rekey_time != cfg->ssh_rekey_time &&
7571 cfg->ssh_rekey_time != 0) {
7572 long new_next = ssh->last_rekey + cfg->ssh_rekey_time*60*TICKSPERSEC;
7573 long now = GETTICKCOUNT();
7574
7575 if (new_next - now < 0) {
f382c87d 7576 rekeying = "timeout shortened";
e6c1536e 7577 } else {
7578 ssh->next_rekey = schedule_timer(new_next - now, ssh2_timer, ssh);
7579 }
7580 }
7581
7582 old_max_data_size = ssh->max_data_size;
7583 ssh->max_data_size = parse_blocksize(cfg->ssh_rekey_data);
7584 if (old_max_data_size != ssh->max_data_size &&
7585 ssh->max_data_size != 0) {
7586 if (ssh->outgoing_data_size > ssh->max_data_size ||
7587 ssh->incoming_data_size > ssh->max_data_size)
f382c87d 7588 rekeying = "data limit lowered";
e6c1536e 7589 }
7590
e13bba36 7591 if (ssh->cfg.compression != cfg->compression) {
f382c87d 7592 rekeying = "compression setting changed";
e13bba36 7593 rekey_mandatory = TRUE;
7594 }
7595
7596 if (ssh->cfg.ssh2_des_cbc != cfg->ssh2_des_cbc ||
7597 memcmp(ssh->cfg.ssh_cipherlist, cfg->ssh_cipherlist,
7598 sizeof(ssh->cfg.ssh_cipherlist))) {
f382c87d 7599 rekeying = "cipher settings changed";
e13bba36 7600 rekey_mandatory = TRUE;
e6c1536e 7601 }
7602
86916870 7603 ssh->cfg = *cfg; /* STRUCTURE COPY */
e13bba36 7604
7605 if (rekeying) {
7606 if (!ssh->kex_in_progress) {
7607 do_ssh2_transport(ssh, rekeying, -1, NULL);
7608 } else if (rekey_mandatory) {
7609 ssh->deferred_rekey_reason = rekeying;
7610 }
7611 }
86916870 7612}
7613
7614/*
374330e2 7615 * Called to send data down the Telnet connection.
7616 */
51470298 7617static int ssh_send(void *handle, char *buf, int len)
32874aea 7618{
51470298 7619 Ssh ssh = (Ssh) handle;
7620
7621 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
5471d09a 7622 return 0;
374330e2 7623
d8baa528 7624 ssh->protocol(ssh, (unsigned char *)buf, len, 0);
5471d09a 7625
51470298 7626 return ssh_sendbuffer(ssh);
5471d09a 7627}
7628
7629/*
7630 * Called to query the current amount of buffered stdin data.
7631 */
51470298 7632static int ssh_sendbuffer(void *handle)
5471d09a 7633{
51470298 7634 Ssh ssh = (Ssh) handle;
5471d09a 7635 int override_value;
7636
51470298 7637 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
5471d09a 7638 return 0;
7639
7640 /*
7641 * If the SSH socket itself has backed up, add the total backup
7642 * size on that to any individual buffer on the stdin channel.
7643 */
7644 override_value = 0;
51470298 7645 if (ssh->throttled_all)
7646 override_value = ssh->overall_bufsize;
5471d09a 7647
51470298 7648 if (ssh->version == 1) {
5471d09a 7649 return override_value;
51470298 7650 } else if (ssh->version == 2) {
7651 if (!ssh->mainchan || ssh->mainchan->closes > 0)
5471d09a 7652 return override_value;
7653 else
51470298 7654 return (override_value +
7655 bufchain_size(&ssh->mainchan->v.v2.outbuffer));
5471d09a 7656 }
7657
7658 return 0;
374330e2 7659}
7660
7661/*
6e48c3fe 7662 * Called to set the size of the window from SSH's POV.
374330e2 7663 */
51470298 7664static void ssh_size(void *handle, int width, int height)
32874aea 7665{
51470298 7666 Ssh ssh = (Ssh) handle;
ff3187f6 7667 struct Packet *pktout;
51470298 7668
7669 ssh->term_width = width;
7670 ssh->term_height = height;
f278d6f8 7671
51470298 7672 switch (ssh->state) {
374330e2 7673 case SSH_STATE_BEFORE_SIZE:
3687d221 7674 case SSH_STATE_PREPACKET:
21248260 7675 case SSH_STATE_CLOSED:
374330e2 7676 break; /* do nothing */
7677 case SSH_STATE_INTERMED:
51470298 7678 ssh->size_needed = TRUE; /* buffer for later */
374330e2 7679 break;
7680 case SSH_STATE_SESSION:
86916870 7681 if (!ssh->cfg.nopty) {
51470298 7682 if (ssh->version == 1) {
7683 send_packet(ssh, SSH1_CMSG_WINDOW_SIZE,
7684 PKT_INT, ssh->term_height,
7685 PKT_INT, ssh->term_width,
32874aea 7686 PKT_INT, 0, PKT_INT, 0, PKT_END);
0ed48730 7687 } else if (ssh->mainchan) {
ff3187f6 7688 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7689 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7690 ssh2_pkt_addstring(pktout, "window-change");
7691 ssh2_pkt_addbool(pktout, 0);
7692 ssh2_pkt_adduint32(pktout, ssh->term_width);
7693 ssh2_pkt_adduint32(pktout, ssh->term_height);
7694 ssh2_pkt_adduint32(pktout, 0);
7695 ssh2_pkt_adduint32(pktout, 0);
7696 ssh2_pkt_send(ssh, pktout);
32874aea 7697 }
7698 }
7699 break;
374330e2 7700 }
7701}
7702
7703/*
125105d1 7704 * Return a list of the special codes that make sense in this
7705 * protocol.
7706 */
7707static const struct telnet_special *ssh_get_specials(void *handle)
7708{
786ba75e 7709 static const struct telnet_special ssh1_ignore_special[] = {
7710 {"IGNORE message", TS_NOP}
7711 };
7712 static const struct telnet_special ssh2_transport_specials[] = {
62638676 7713 {"IGNORE message", TS_NOP},
9442dd57 7714 {"Repeat key exchange", TS_REKEY},
62638676 7715 };
7716 static const struct telnet_special ssh2_session_specials[] = {
6f2d0cde 7717 {NULL, TS_SEP},
7718 {"Break", TS_BRK},
786ba75e 7719 /* These are the signal names defined by draft-ietf-secsh-connect-23.
6f2d0cde 7720 * They include all the ISO C signals, but are a subset of the POSIX
7721 * required signals. */
7722 {"SIGINT (Interrupt)", TS_SIGINT},
7723 {"SIGTERM (Terminate)", TS_SIGTERM},
7724 {"SIGKILL (Kill)", TS_SIGKILL},
7725 {"SIGQUIT (Quit)", TS_SIGQUIT},
7726 {"SIGHUP (Hangup)", TS_SIGHUP},
7727 {"More signals", TS_SUBMENU},
7728 {"SIGABRT", TS_SIGABRT}, {"SIGALRM", TS_SIGALRM},
7729 {"SIGFPE", TS_SIGFPE}, {"SIGILL", TS_SIGILL},
7730 {"SIGPIPE", TS_SIGPIPE}, {"SIGSEGV", TS_SIGSEGV},
7731 {"SIGUSR1", TS_SIGUSR1}, {"SIGUSR2", TS_SIGUSR2},
7732 {NULL, TS_EXITMENU}
62638676 7733 };
7734 static const struct telnet_special specials_end[] = {
6f2d0cde 7735 {NULL, TS_EXITMENU}
62638676 7736 };
786ba75e 7737 /* XXX review this length for any changes: */
7738 static struct telnet_special ssh_specials[lenof(ssh2_transport_specials) +
62638676 7739 lenof(ssh2_session_specials) +
7740 lenof(specials_end)];
125105d1 7741 Ssh ssh = (Ssh) handle;
62638676 7742 int i = 0;
7743#define ADD_SPECIALS(name) \
7744 do { \
7745 assert((i + lenof(name)) <= lenof(ssh_specials)); \
7746 memcpy(&ssh_specials[i], name, sizeof name); \
7747 i += lenof(name); \
7748 } while(0)
125105d1 7749
7750 if (ssh->version == 1) {
62638676 7751 /* Don't bother offering IGNORE if we've decided the remote
7752 * won't cope with it, since we wouldn't bother sending it if
7753 * asked anyway. */
7754 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE))
786ba75e 7755 ADD_SPECIALS(ssh1_ignore_special);
125105d1 7756 } else if (ssh->version == 2) {
786ba75e 7757 ADD_SPECIALS(ssh2_transport_specials);
62638676 7758 if (ssh->mainchan)
7759 ADD_SPECIALS(ssh2_session_specials);
7760 } /* else we're not ready yet */
7761
7762 if (i) {
7763 ADD_SPECIALS(specials_end);
7764 return ssh_specials;
7765 } else {
125105d1 7766 return NULL;
62638676 7767 }
7768#undef ADD_SPECIALS
125105d1 7769}
7770
7771/*
6abbf9e3 7772 * Send Telnet special codes. TS_EOF is useful for `plink', so you
7773 * can send an EOF and collect resulting output (e.g. `plink
7774 * hostname sort').
374330e2 7775 */
51470298 7776static void ssh_special(void *handle, Telnet_Special code)
32874aea 7777{
51470298 7778 Ssh ssh = (Ssh) handle;
ff3187f6 7779 struct Packet *pktout;
51470298 7780
6abbf9e3 7781 if (code == TS_EOF) {
51470298 7782 if (ssh->state != SSH_STATE_SESSION) {
32874aea 7783 /*
7784 * Buffer the EOF in case we are pre-SESSION, so we can
7785 * send it as soon as we reach SESSION.
7786 */
7787 if (code == TS_EOF)
51470298 7788 ssh->eof_needed = TRUE;
32874aea 7789 return;
7790 }
51470298 7791 if (ssh->version == 1) {
7792 send_packet(ssh, SSH1_CMSG_EOF, PKT_END);
0ed48730 7793 } else if (ssh->mainchan) {
ff3187f6 7794 struct Packet *pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF);
7795 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7796 ssh2_pkt_send(ssh, pktout);
32874aea 7797 }
7798 logevent("Sent EOF message");
125105d1 7799 } else if (code == TS_PING || code == TS_NOP) {
51470298 7800 if (ssh->state == SSH_STATE_CLOSED
7801 || ssh->state == SSH_STATE_PREPACKET) return;
7802 if (ssh->version == 1) {
7803 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE))
7804 send_packet(ssh, SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
32874aea 7805 } else {
ff3187f6 7806 pktout = ssh2_pkt_init(SSH2_MSG_IGNORE);
7807 ssh2_pkt_addstring_start(pktout);
590f6a5f 7808 ssh2_pkt_send_noqueue(ssh, pktout);
32874aea 7809 }
9442dd57 7810 } else if (code == TS_REKEY) {
7811 if (!ssh->kex_in_progress && ssh->version == 2) {
f382c87d 7812 do_ssh2_transport(ssh, "at user request", -1, NULL);
9442dd57 7813 }
125105d1 7814 } else if (code == TS_BRK) {
7815 if (ssh->state == SSH_STATE_CLOSED
7816 || ssh->state == SSH_STATE_PREPACKET) return;
7817 if (ssh->version == 1) {
7818 logevent("Unable to send BREAK signal in SSH1");
0ed48730 7819 } else if (ssh->mainchan) {
ff3187f6 7820 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7821 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7822 ssh2_pkt_addstring(pktout, "break");
7823 ssh2_pkt_addbool(pktout, 0);
7824 ssh2_pkt_adduint32(pktout, 0); /* default break length */
7825 ssh2_pkt_send(ssh, pktout);
125105d1 7826 }
6abbf9e3 7827 } else {
6f2d0cde 7828 /* Is is a POSIX signal? */
7829 char *signame = NULL;
7830 if (code == TS_SIGABRT) signame = "ABRT";
7831 if (code == TS_SIGALRM) signame = "ALRM";
7832 if (code == TS_SIGFPE) signame = "FPE";
7833 if (code == TS_SIGHUP) signame = "HUP";
7834 if (code == TS_SIGILL) signame = "ILL";
7835 if (code == TS_SIGINT) signame = "INT";
7836 if (code == TS_SIGKILL) signame = "KILL";
7837 if (code == TS_SIGPIPE) signame = "PIPE";
7838 if (code == TS_SIGQUIT) signame = "QUIT";
7839 if (code == TS_SIGSEGV) signame = "SEGV";
7840 if (code == TS_SIGTERM) signame = "TERM";
7841 if (code == TS_SIGUSR1) signame = "USR1";
7842 if (code == TS_SIGUSR2) signame = "USR2";
7843 /* The SSH-2 protocol does in principle support arbitrary named
7844 * signals, including signame@domain, but we don't support those. */
7845 if (signame) {
7846 /* It's a signal. */
7847 if (ssh->version == 2 && ssh->mainchan) {
ff3187f6 7848 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7849 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7850 ssh2_pkt_addstring(pktout, "signal");
7851 ssh2_pkt_addbool(pktout, 0);
7852 ssh2_pkt_addstring(pktout, signame);
7853 ssh2_pkt_send(ssh, pktout);
6f2d0cde 7854 logeventf(ssh, "Sent signal SIG%s", signame);
7855 }
7856 } else {
7857 /* Never heard of it. Do nothing */
7858 }
6abbf9e3 7859 }
374330e2 7860}
7861
51470298 7862void *new_sock_channel(void *handle, Socket s)
d74d141c 7863{
51470298 7864 Ssh ssh = (Ssh) handle;
d74d141c 7865 struct ssh_channel *c;
3d88e64d 7866 c = snew(struct ssh_channel);
51470298 7867 c->ssh = ssh;
d74d141c 7868
7869 if (c) {
bc240b21 7870 c->remoteid = -1; /* to be set when open confirmed */
51470298 7871 c->localid = alloc_channel_id(ssh);
d74d141c 7872 c->closes = 0;
bc240b21 7873 c->type = CHAN_SOCKDATA_DORMANT;/* identify channel type */
d74d141c 7874 c->u.pfd.s = s;
013dd8c0 7875 bufchain_init(&c->v.v2.outbuffer);
51470298 7876 add234(ssh->channels, c);
d74d141c 7877 }
7878 return c;
7879}
7880
5471d09a 7881/*
7882 * This is called when stdout/stderr (the entity to which
7883 * from_backend sends data) manages to clear some backlog.
7884 */
ae9ae89f 7885static void ssh_unthrottle(void *handle, int bufsize)
5471d09a 7886{
51470298 7887 Ssh ssh = (Ssh) handle;
7888 if (ssh->version == 1) {
7889 if (ssh->v1_stdout_throttling && bufsize < SSH1_BUFFER_LIMIT) {
7890 ssh->v1_stdout_throttling = 0;
7891 ssh1_throttle(ssh, -1);
5471d09a 7892 }
7893 } else {
51470298 7894 if (ssh->mainchan && ssh->mainchan->closes == 0)
7895 ssh2_set_window(ssh->mainchan, OUR_V2_WINSIZE - bufsize);
5471d09a 7896 }
7897}
7898
6b78788a 7899void ssh_send_port_open(void *channel, char *hostname, int port, char *org)
d74d141c 7900{
7901 struct ssh_channel *c = (struct ssh_channel *)channel;
6b78788a 7902 Ssh ssh = c->ssh;
ff3187f6 7903 struct Packet *pktout;
d74d141c 7904
57356d63 7905 logeventf(ssh, "Opening forwarded connection to %s:%d", hostname, port);
d74d141c 7906
51470298 7907 if (ssh->version == 1) {
7908 send_packet(ssh, SSH1_MSG_PORT_OPEN,
bc240b21 7909 PKT_INT, c->localid,
7910 PKT_STR, hostname,
7911 PKT_INT, port,
31fb1866 7912 /* PKT_STR, <org:orgport>, */
bc240b21 7913 PKT_END);
7914 } else {
ff3187f6 7915 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
7916 ssh2_pkt_addstring(pktout, "direct-tcpip");
7917 ssh2_pkt_adduint32(pktout, c->localid);
5471d09a 7918 c->v.v2.locwindow = OUR_V2_WINSIZE;
ff3187f6 7919 ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);/* our window size */
7920 ssh2_pkt_adduint32(pktout, 0x4000UL); /* our max pkt size */
7921 ssh2_pkt_addstring(pktout, hostname);
7922 ssh2_pkt_adduint32(pktout, port);
bc240b21 7923 /*
7924 * We make up values for the originator data; partly it's
7925 * too much hassle to keep track, and partly I'm not
7926 * convinced the server should be told details like that
7927 * about my local network configuration.
7928 */
ff3187f6 7929 ssh2_pkt_addstring(pktout, "client-side-connection");
7930 ssh2_pkt_adduint32(pktout, 0);
7931 ssh2_pkt_send(ssh, pktout);
bc240b21 7932 }
d74d141c 7933}
7934
51470298 7935static Socket ssh_socket(void *handle)
32874aea 7936{
51470298 7937 Ssh ssh = (Ssh) handle;
7938 return ssh->s;
32874aea 7939}
8ccc75b0 7940
51470298 7941static int ssh_sendok(void *handle)
32874aea 7942{
51470298 7943 Ssh ssh = (Ssh) handle;
7944 return ssh->send_ok;
32874aea 7945}
fb09bf1c 7946
51470298 7947static int ssh_ldisc(void *handle, int option)
32874aea 7948{
51470298 7949 Ssh ssh = (Ssh) handle;
32874aea 7950 if (option == LD_ECHO)
51470298 7951 return ssh->echoing;
32874aea 7952 if (option == LD_EDIT)
51470298 7953 return ssh->editing;
0965bee0 7954 return FALSE;
7955}
7956
b9d7bcad 7957static void ssh_provide_ldisc(void *handle, void *ldisc)
7958{
7959 Ssh ssh = (Ssh) handle;
7960 ssh->ldisc = ldisc;
7961}
7962
a8327734 7963static void ssh_provide_logctx(void *handle, void *logctx)
7964{
7965 Ssh ssh = (Ssh) handle;
7966 ssh->logctx = logctx;
7967}
7968
51470298 7969static int ssh_return_exitcode(void *handle)
7970{
7971 Ssh ssh = (Ssh) handle;
3bb2f322 7972 if (ssh->s != NULL)
7973 return -1;
7974 else
7975 return (ssh->exitcode >= 0 ? ssh->exitcode : 0);
51470298 7976}
7977
7978/*
f89c3294 7979 * cfg_info for SSH is the currently running version of the
7980 * protocol. (1 for 1; 2 for 2; 0 for not-decided-yet.)
7981 */
7982static int ssh_cfg_info(void *handle)
7983{
7984 Ssh ssh = (Ssh) handle;
7985 return ssh->version;
7986}
7987
7988/*
51470298 7989 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
7990 * that fails. This variable is the means by which scp.c can reach
7991 * into the SSH code and find out which one it got.
7992 */
7993extern int ssh_fallback_cmd(void *handle)
d8d6c7e5 7994{
51470298 7995 Ssh ssh = (Ssh) handle;
7996 return ssh->fallback_cmd;
d8d6c7e5 7997}
7998
374330e2 7999Backend ssh_backend = {
8000 ssh_init,
fabd1805 8001 ssh_free,
86916870 8002 ssh_reconfig,
374330e2 8003 ssh_send,
5471d09a 8004 ssh_sendbuffer,
374330e2 8005 ssh_size,
4017be6d 8006 ssh_special,
125105d1 8007 ssh_get_specials,
8ccc75b0 8008 ssh_socket,
d8d6c7e5 8009 ssh_return_exitcode,
97db3be4 8010 ssh_sendok,
0965bee0 8011 ssh_ldisc,
b9d7bcad 8012 ssh_provide_ldisc,
a8327734 8013 ssh_provide_logctx,
5471d09a 8014 ssh_unthrottle,
f89c3294 8015 ssh_cfg_info,
97db3be4 8016 22
bc240b21 8017};
Local modifications for Simon Tatham's `PuTTY' SSH client and terminal emulator