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Owen tells me the Mac compiler complains at a char / unsigned char
[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);
ac934965 564static int ssh_do_close(Ssh ssh, int notify_exit);
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;
ac934965 645 int close_expected;
51470298 646
fda2feb1 647 tree234 *rportfwds, *portfwds;
51470298 648
649 enum {
650 SSH_STATE_PREPACKET,
651 SSH_STATE_BEFORE_SIZE,
652 SSH_STATE_INTERMED,
653 SSH_STATE_SESSION,
654 SSH_STATE_CLOSED
655 } state;
656
657 int size_needed, eof_needed;
658
590f6a5f 659 struct Packet **queue;
660 int queuelen, queuesize;
661 int queueing;
51470298 662 unsigned char *deferred_send_data;
663 int deferred_len, deferred_size;
664
665 /*
666 * Gross hack: pscp will try to start SFTP but fall back to
667 * scp1 if that fails. This variable is the means by which
668 * scp.c can reach into the SSH code and find out which one it
669 * got.
670 */
671 int fallback_cmd;
672
673 /*
674 * Used for username and password input.
675 */
676 char *userpass_input_buffer;
677 int userpass_input_buflen;
678 int userpass_input_bufpos;
679 int userpass_input_echo;
680
51470298 681 int pkt_ctx;
682
302121de 683 void *x11auth;
684
51470298 685 int version;
686 int v1_throttle_count;
687 int overall_bufsize;
688 int throttled_all;
689 int v1_stdout_throttling;
690 int v2_outgoing_sequence;
691
692 int ssh1_rdpkt_crstate;
693 int ssh2_rdpkt_crstate;
694 int do_ssh_init_crstate;
695 int ssh_gotdata_crstate;
51470298 696 int do_ssh1_login_crstate;
b09eaa88 697 int do_ssh1_connection_crstate;
51470298 698 int do_ssh2_transport_crstate;
699 int do_ssh2_authconn_crstate;
700
701 void *do_ssh_init_state;
702 void *do_ssh1_login_state;
703 void *do_ssh2_transport_state;
704 void *do_ssh2_authconn_state;
705
706 struct rdpkt1_state_tag rdpkt1_state;
707 struct rdpkt2_state_tag rdpkt2_state;
708
b09eaa88 709 /* ssh1 and ssh2 use this for different things, but both use it */
710 int protocol_initial_phase_done;
711
ff3187f6 712 void (*protocol) (Ssh ssh, unsigned char *in, int inlen,
713 struct Packet *pkt);
714 struct Packet *(*s_rdpkt) (Ssh ssh, unsigned char **data, int *datalen);
86916870 715
716 /*
717 * We maintain a full _copy_ of a Config structure here, not
718 * merely a pointer to it. That way, when we're passed a new
719 * one for reconfiguration, we can check the differences and
720 * potentially reconfigure port forwardings etc in mid-session.
721 */
722 Config cfg;
839f10db 723
724 /*
725 * Used to transfer data back from async agent callbacks.
726 */
727 void *agent_response;
728 int agent_response_len;
b09eaa88 729
730 /*
731 * Dispatch table for packet types that we may have to deal
732 * with at any time.
733 */
734 handler_fn_t packet_dispatch[256];
39934deb 735
736 /*
06fadff5 737 * Queues of one-off handler functions for success/failure
738 * indications from a request.
739 */
740 struct queued_handler *qhead, *qtail;
741
742 /*
39934deb 743 * This module deals with sending keepalives.
744 */
745 Pinger pinger;
9442dd57 746
747 /*
748 * Track incoming and outgoing data sizes and time, for
749 * size-based rekeys.
750 */
751 unsigned long incoming_data_size, outgoing_data_size, deferred_data_size;
d57f70af 752 unsigned long max_data_size;
9442dd57 753 int kex_in_progress;
e6c1536e 754 long next_rekey, last_rekey;
e13bba36 755 char *deferred_rekey_reason; /* points to STATIC string; don't free */
51470298 756};
960e736a 757
382908ad 758#define logevent(s) logevent(ssh->frontend, s)
a8327734 759
760/* logevent, only printf-formatted. */
cbe2d68f 761static void logeventf(Ssh ssh, const char *fmt, ...)
a8327734 762{
763 va_list ap;
57356d63 764 char *buf;
a8327734 765
766 va_start(ap, fmt);
57356d63 767 buf = dupvprintf(fmt, ap);
a8327734 768 va_end(ap);
57356d63 769 logevent(buf);
57356d63 770 sfree(buf);
a8327734 771}
772
6b5cf8b4 773#define bombout(msg) \
774 do { \
775 char *text = dupprintf msg; \
ac934965 776 ssh_do_close(ssh, FALSE); \
6b5cf8b4 777 logevent(text); \
778 connection_fatal(ssh->frontend, "%s", text); \
779 sfree(text); \
780 } while (0)
a8327734 781
9a10ecf4 782/* Functions to leave bits out of the SSH packet log file. */
783
ff3187f6 784static void dont_log_password(Ssh ssh, struct Packet *pkt, int blanktype)
9a10ecf4 785{
786 if (ssh->cfg.logomitpass)
ff3187f6 787 pkt->logmode = blanktype;
9a10ecf4 788}
789
ff3187f6 790static void dont_log_data(Ssh ssh, struct Packet *pkt, int blanktype)
9a10ecf4 791{
792 if (ssh->cfg.logomitdata)
ff3187f6 793 pkt->logmode = blanktype;
9a10ecf4 794}
795
ff3187f6 796static void end_log_omission(Ssh ssh, struct Packet *pkt)
9a10ecf4 797{
ff3187f6 798 pkt->logmode = PKTLOG_EMIT;
9a10ecf4 799}
800
32874aea 801static int ssh_channelcmp(void *av, void *bv)
802{
803 struct ssh_channel *a = (struct ssh_channel *) av;
804 struct ssh_channel *b = (struct ssh_channel *) bv;
805 if (a->localid < b->localid)
806 return -1;
807 if (a->localid > b->localid)
808 return +1;
dacbd0e8 809 return 0;
810}
32874aea 811static int ssh_channelfind(void *av, void *bv)
812{
813 unsigned *a = (unsigned *) av;
814 struct ssh_channel *b = (struct ssh_channel *) bv;
815 if (*a < b->localid)
816 return -1;
817 if (*a > b->localid)
818 return +1;
dacbd0e8 819 return 0;
820}
821
bc240b21 822static int ssh_rportcmp_ssh1(void *av, void *bv)
d74d141c 823{
824 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
825 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
826 int i;
bc240b21 827 if ( (i = strcmp(a->dhost, b->dhost)) != 0)
d74d141c 828 return i < 0 ? -1 : +1;
bc240b21 829 if (a->dport > b->dport)
830 return +1;
831 if (a->dport < b->dport)
832 return -1;
833 return 0;
834}
835
836static int ssh_rportcmp_ssh2(void *av, void *bv)
837{
838 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
839 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
cdcbdf3b 840
bc240b21 841 if (a->sport > b->sport)
d74d141c 842 return +1;
bc240b21 843 if (a->sport < b->sport)
844 return -1;
d74d141c 845 return 0;
846}
847
fda2feb1 848/*
849 * Special form of strcmp which can cope with NULL inputs. NULL is
850 * defined to sort before even the empty string.
851 */
852static int nullstrcmp(const char *a, const char *b)
853{
854 if (a == NULL && b == NULL)
855 return 0;
856 if (a == NULL)
857 return -1;
858 if (b == NULL)
859 return +1;
860 return strcmp(a, b);
861}
862
863static int ssh_portcmp(void *av, void *bv)
864{
865 struct ssh_portfwd *a = (struct ssh_portfwd *) av;
866 struct ssh_portfwd *b = (struct ssh_portfwd *) bv;
867 int i;
868 if (a->type > b->type)
869 return +1;
870 if (a->type < b->type)
871 return -1;
84328ddb 872 if (a->addressfamily > b->addressfamily)
873 return +1;
874 if (a->addressfamily < b->addressfamily)
875 return -1;
fda2feb1 876 if ( (i = nullstrcmp(a->saddr, b->saddr)) != 0)
877 return i < 0 ? -1 : +1;
878 if (a->sport > b->sport)
879 return +1;
880 if (a->sport < b->sport)
881 return -1;
882 if (a->type != 'D') {
883 if ( (i = nullstrcmp(a->daddr, b->daddr)) != 0)
884 return i < 0 ? -1 : +1;
885 if (a->dport > b->dport)
886 return +1;
887 if (a->dport < b->dport)
888 return -1;
889 }
890 return 0;
891}
892
51470298 893static int alloc_channel_id(Ssh ssh)
32874aea 894{
260f3dec 895 const unsigned CHANNEL_NUMBER_OFFSET = 256;
896 unsigned low, high, mid;
d2371c81 897 int tsize;
898 struct ssh_channel *c;
899
900 /*
901 * First-fit allocation of channel numbers: always pick the
902 * lowest unused one. To do this, binary-search using the
903 * counted B-tree to find the largest channel ID which is in a
904 * contiguous sequence from the beginning. (Precisely
905 * everything in that sequence must have ID equal to its tree
906 * index plus CHANNEL_NUMBER_OFFSET.)
907 */
51470298 908 tsize = count234(ssh->channels);
d2371c81 909
32874aea 910 low = -1;
911 high = tsize;
d2371c81 912 while (high - low > 1) {
913 mid = (high + low) / 2;
51470298 914 c = index234(ssh->channels, mid);
d2371c81 915 if (c->localid == mid + CHANNEL_NUMBER_OFFSET)
916 low = mid; /* this one is fine */
917 else
918 high = mid; /* this one is past it */
919 }
920 /*
921 * Now low points to either -1, or the tree index of the
922 * largest ID in the initial sequence.
923 */
924 {
925 unsigned i = low + 1 + CHANNEL_NUMBER_OFFSET;
51470298 926 assert(NULL == find234(ssh->channels, &i, ssh_channelfind));
d2371c81 927 }
928 return low + 1 + CHANNEL_NUMBER_OFFSET;
929}
930
9fab77dc 931static void c_write(Ssh ssh, const char *buf, int len)
32874aea 932{
67779be7 933 if ((flags & FLAG_STDERR)) {
32874aea 934 int i;
935 for (i = 0; i < len; i++)
936 if (buf[i] != '\r')
937 fputc(buf[i], stderr);
fb09bf1c 938 return;
939 }
51470298 940 from_backend(ssh->frontend, 1, buf, len);
3bdaf79d 941}
942
9fab77dc 943static void c_write_untrusted(Ssh ssh, const char *buf, int len)
32874aea 944{
a209e957 945 int i;
946 for (i = 0; i < len; i++) {
32874aea 947 if (buf[i] == '\n')
51470298 948 c_write(ssh, "\r\n", 2);
32874aea 949 else if ((buf[i] & 0x60) || (buf[i] == '\r'))
51470298 950 c_write(ssh, buf + i, 1);
a209e957 951 }
952}
953
9fab77dc 954static void c_write_str(Ssh ssh, const char *buf)
32874aea 955{
51470298 956 c_write(ssh, buf, strlen(buf));
1408a877 957}
958
ff3187f6 959static void ssh_free_packet(struct Packet *pkt)
960{
961 sfree(pkt->data);
962 sfree(pkt);
963}
964static struct Packet *ssh_new_packet(void)
965{
966 struct Packet *pkt = snew(struct Packet);
967
968 pkt->data = NULL;
969 pkt->maxlen = 0;
970 pkt->logmode = PKTLOG_EMIT;
971 pkt->nblanks = 0;
972 pkt->blanks = NULL;
973
974 return pkt;
975}
976
fb09bf1c 977/*
978 * Collect incoming data in the incoming packet buffer.
e5574168 979 * Decipher and verify the packet when it is completely read.
980 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
fb09bf1c 981 * Update the *data and *datalen variables.
ff3187f6 982 * Return a Packet structure when a packet is completed.
fb09bf1c 983 */
ff3187f6 984static struct Packet *ssh1_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
fb09bf1c 985{
51470298 986 struct rdpkt1_state_tag *st = &ssh->rdpkt1_state;
374330e2 987
51470298 988 crBegin(ssh->ssh1_rdpkt_crstate);
374330e2 989
ff3187f6 990 st->pktin = ssh_new_packet();
991
992 st->pktin->type = 0;
993 st->pktin->length = 0;
374330e2 994
57476f6b 995 for (st->i = st->len = 0; st->i < 4; st->i++) {
fb09bf1c 996 while ((*datalen) == 0)
ff3187f6 997 crReturn(NULL);
57476f6b 998 st->len = (st->len << 8) + **data;
fb09bf1c 999 (*data)++, (*datalen)--;
1000 }
374330e2 1001
57476f6b 1002 st->pad = 8 - (st->len % 8);
1003 st->biglen = st->len + st->pad;
ff3187f6 1004 st->pktin->length = st->len - 5;
fb09bf1c 1005
ae0500e5 1006 if (st->biglen < 0) {
1007 bombout(("Extremely large packet length from server suggests"
1008 " data stream corruption"));
ff3187f6 1009 ssh_free_packet(st->pktin);
1010 crStop(NULL);
ae0500e5 1011 }
1012
ff3187f6 1013 st->pktin->maxlen = st->biglen;
1014 st->pktin->data = snewn(st->biglen + APIEXTRA, unsigned char);
374330e2 1015
57476f6b 1016 st->to_read = st->biglen;
ff3187f6 1017 st->p = st->pktin->data;
57476f6b 1018 while (st->to_read > 0) {
32874aea 1019 st->chunk = st->to_read;
fb09bf1c 1020 while ((*datalen) == 0)
ff3187f6 1021 crReturn(NULL);
57476f6b 1022 if (st->chunk > (*datalen))
1023 st->chunk = (*datalen);
1024 memcpy(st->p, *data, st->chunk);
1025 *data += st->chunk;
1026 *datalen -= st->chunk;
1027 st->p += st->chunk;
1028 st->to_read -= st->chunk;
fb09bf1c 1029 }
374330e2 1030
ff3187f6 1031 if (ssh->cipher && detect_attack(ssh->crcda_ctx, st->pktin->data,
0183b242 1032 st->biglen, NULL)) {
6b5cf8b4 1033 bombout(("Network attack (CRC compensation) detected!"));
ff3187f6 1034 ssh_free_packet(st->pktin);
1035 crStop(NULL);
9a3a93a5 1036 }
1037
51470298 1038 if (ssh->cipher)
ff3187f6 1039 ssh->cipher->decrypt(ssh->v1_cipher_ctx, st->pktin->data, st->biglen);
374330e2 1040
ff3187f6 1041 st->realcrc = crc32_compute(st->pktin->data, st->biglen - 4);
1042 st->gotcrc = GET_32BIT(st->pktin->data + st->biglen - 4);
57476f6b 1043 if (st->gotcrc != st->realcrc) {
6b5cf8b4 1044 bombout(("Incorrect CRC received on packet"));
ff3187f6 1045 ssh_free_packet(st->pktin);
1046 crStop(NULL);
fb09bf1c 1047 }
572f871e 1048
ff3187f6 1049 st->pktin->body = st->pktin->data + st->pad + 1;
1050 st->pktin->savedpos = 0;
4ba9b64b 1051
51470298 1052 if (ssh->v1_compressing) {
4ba9b64b 1053 unsigned char *decompblk;
1054 int decomplen;
36b8d9bb 1055 if (!zlib_decompress_block(ssh->sc_comp_ctx,
ff3187f6 1056 st->pktin->body - 1, st->pktin->length + 1,
36b8d9bb 1057 &decompblk, &decomplen)) {
1058 bombout(("Zlib decompression encountered invalid data"));
ff3187f6 1059 ssh_free_packet(st->pktin);
1060 crStop(NULL);
36b8d9bb 1061 }
4ba9b64b 1062
ff3187f6 1063 if (st->pktin->maxlen < st->pad + decomplen) {
1064 st->pktin->maxlen = st->pad + decomplen;
1065 st->pktin->data = sresize(st->pktin->data,
1066 st->pktin->maxlen + APIEXTRA,
3d88e64d 1067 unsigned char);
ff3187f6 1068 st->pktin->body = st->pktin->data + st->pad + 1;
4ba9b64b 1069 }
1070
ff3187f6 1071 memcpy(st->pktin->body - 1, decompblk, decomplen);
dcbde236 1072 sfree(decompblk);
ff3187f6 1073 st->pktin->length = decomplen - 1;
4ba9b64b 1074 }
1075
ff3187f6 1076 st->pktin->type = st->pktin->body[-1];
00db133f 1077
9a10ecf4 1078 /*
1079 * Log incoming packet, possibly omitting sensitive fields.
1080 */
1081 if (ssh->logctx) {
1082 int nblanks = 0;
1083 struct logblank_t blank;
1084 if (ssh->cfg.logomitdata) {
1085 int do_blank = FALSE, blank_prefix = 0;
1086 /* "Session data" packets - omit the data field */
ff3187f6 1087 if ((st->pktin->type == SSH1_SMSG_STDOUT_DATA) ||
1088 (st->pktin->type == SSH1_SMSG_STDERR_DATA)) {
9a10ecf4 1089 do_blank = TRUE; blank_prefix = 0;
ff3187f6 1090 } else if (st->pktin->type == SSH1_MSG_CHANNEL_DATA) {
9a10ecf4 1091 do_blank = TRUE; blank_prefix = 4;
1092 }
1093 if (do_blank) {
1094 blank.offset = blank_prefix;
ff3187f6 1095 blank.len = st->pktin->length;
9a10ecf4 1096 blank.type = PKTLOG_OMIT;
1097 nblanks = 1;
1098 }
1099 }
a8327734 1100 log_packet(ssh->logctx,
ff3187f6 1101 PKT_INCOMING, st->pktin->type,
1102 ssh1_pkt_type(st->pktin->type),
1103 st->pktin->body, st->pktin->length,
9a10ecf4 1104 nblanks, &blank);
1105 }
00db133f 1106
ff3187f6 1107 crFinish(st->pktin);
fb09bf1c 1108}
1109
ff3187f6 1110static struct Packet *ssh2_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
e5574168 1111{
51470298 1112 struct rdpkt2_state_tag *st = &ssh->rdpkt2_state;
e5574168 1113
51470298 1114 crBegin(ssh->ssh2_rdpkt_crstate);
e5574168 1115
ff3187f6 1116 st->pktin = ssh_new_packet();
1117
1118 st->pktin->type = 0;
1119 st->pktin->length = 0;
51470298 1120 if (ssh->sccipher)
1121 st->cipherblk = ssh->sccipher->blksize;
e5574168 1122 else
32874aea 1123 st->cipherblk = 8;
960e736a 1124 if (st->cipherblk < 8)
32874aea 1125 st->cipherblk = 8;
960e736a 1126
ff3187f6 1127 st->pktin->data = snewn(st->cipherblk + APIEXTRA, unsigned char);
e5574168 1128
1129 /*
1130 * Acquire and decrypt the first block of the packet. This will
1131 * contain the length and padding details.
1132 */
32874aea 1133 for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) {
e5574168 1134 while ((*datalen) == 0)
ff3187f6 1135 crReturn(NULL);
1136 st->pktin->data[st->i] = *(*data)++;
32874aea 1137 (*datalen)--;
e5574168 1138 }
4252c9cc 1139
51470298 1140 if (ssh->sccipher)
371e569c 1141 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
ff3187f6 1142 st->pktin->data, st->cipherblk);
e5574168 1143
1144 /*
1145 * Now get the length and padding figures.
1146 */
ff3187f6 1147 st->len = GET_32BIT(st->pktin->data);
1148 st->pad = st->pktin->data[4];
e5574168 1149
1150 /*
717dc483 1151 * _Completely_ silly lengths should be stomped on before they
1152 * do us any more damage.
1153 */
1154 if (st->len < 0 || st->pad < 0 || st->len + st->pad < 0) {
6b5cf8b4 1155 bombout(("Incoming packet was garbled on decryption"));
ff3187f6 1156 ssh_free_packet(st->pktin);
1157 crStop(NULL);
717dc483 1158 }
1159
1160 /*
e5574168 1161 * This enables us to deduce the payload length.
1162 */
960e736a 1163 st->payload = st->len - st->pad - 1;
e5574168 1164
ff3187f6 1165 st->pktin->length = st->payload + 5;
e5574168 1166
1167 /*
1168 * So now we can work out the total packet length.
1169 */
960e736a 1170 st->packetlen = st->len + 4;
51470298 1171 st->maclen = ssh->scmac ? ssh->scmac->len : 0;
e5574168 1172
1173 /*
ff3187f6 1174 * Allocate memory for the rest of the packet.
e5574168 1175 */
ff3187f6 1176 st->pktin->maxlen = st->packetlen + st->maclen;
1177 st->pktin->data = sresize(st->pktin->data,
1178 st->pktin->maxlen + APIEXTRA,
1179 unsigned char);
e5574168 1180
1181 /*
1182 * Read and decrypt the remainder of the packet.
1183 */
32874aea 1184 for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen;
1185 st->i++) {
e5574168 1186 while ((*datalen) == 0)
ff3187f6 1187 crReturn(NULL);
1188 st->pktin->data[st->i] = *(*data)++;
32874aea 1189 (*datalen)--;
e5574168 1190 }
1191 /* Decrypt everything _except_ the MAC. */
51470298 1192 if (ssh->sccipher)
371e569c 1193 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
ff3187f6 1194 st->pktin->data + st->cipherblk,
51470298 1195 st->packetlen - st->cipherblk);
e5574168 1196
9442dd57 1197 st->pktin->encrypted_len = st->packetlen;
1198
e5574168 1199 /*
1200 * Check the MAC.
1201 */
51470298 1202 if (ssh->scmac
ff3187f6 1203 && !ssh->scmac->verify(ssh->sc_mac_ctx, st->pktin->data, st->len + 4,
51470298 1204 st->incoming_sequence)) {
6b5cf8b4 1205 bombout(("Incorrect MAC received on packet"));
ff3187f6 1206 ssh_free_packet(st->pktin);
1207 crStop(NULL);
8d5de777 1208 }
b09eaa88 1209
1210 st->pktin->sequence = st->incoming_sequence++;
e5574168 1211
4ba9b64b 1212 /*
1213 * Decompress packet payload.
1214 */
1215 {
1216 unsigned char *newpayload;
1217 int newlen;
51470298 1218 if (ssh->sccomp &&
5366aed8 1219 ssh->sccomp->decompress(ssh->sc_comp_ctx,
ff3187f6 1220 st->pktin->data + 5, st->pktin->length - 5,
51470298 1221 &newpayload, &newlen)) {
ff3187f6 1222 if (st->pktin->maxlen < newlen + 5) {
1223 st->pktin->maxlen = newlen + 5;
1224 st->pktin->data = sresize(st->pktin->data,
1225 st->pktin->maxlen + APIEXTRA,
3d88e64d 1226 unsigned char);
4ba9b64b 1227 }
ff3187f6 1228 st->pktin->length = 5 + newlen;
1229 memcpy(st->pktin->data + 5, newpayload, newlen);
dcbde236 1230 sfree(newpayload);
4ba9b64b 1231 }
1232 }
1233
ff3187f6 1234 st->pktin->savedpos = 6;
1235 st->pktin->body = st->pktin->data;
1236 st->pktin->type = st->pktin->data[5];
e5574168 1237
9a10ecf4 1238 /*
1239 * Log incoming packet, possibly omitting sensitive fields.
1240 */
1241 if (ssh->logctx) {
1242 int nblanks = 0;
1243 struct logblank_t blank;
1244 if (ssh->cfg.logomitdata) {
1245 int do_blank = FALSE, blank_prefix = 0;
1246 /* "Session data" packets - omit the data field */
ff3187f6 1247 if (st->pktin->type == SSH2_MSG_CHANNEL_DATA) {
9a10ecf4 1248 do_blank = TRUE; blank_prefix = 4;
ff3187f6 1249 } else if (st->pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
9a10ecf4 1250 do_blank = TRUE; blank_prefix = 8;
1251 }
1252 if (do_blank) {
1253 blank.offset = blank_prefix;
ff3187f6 1254 blank.len = (st->pktin->length-6) - blank_prefix;
9a10ecf4 1255 blank.type = PKTLOG_OMIT;
1256 nblanks = 1;
1257 }
1258 }
ff3187f6 1259 log_packet(ssh->logctx, PKT_INCOMING, st->pktin->type,
1260 ssh2_pkt_type(ssh->pkt_ctx, st->pktin->type),
1261 st->pktin->data+6, st->pktin->length-6,
9a10ecf4 1262 nblanks, &blank);
1263 }
00db133f 1264
ff3187f6 1265 crFinish(st->pktin);
e5574168 1266}
1267
ff3187f6 1268static void ssh1_pktout_size(struct Packet *pkt, int len)
32874aea 1269{
374330e2 1270 int pad, biglen;
1271
1272 len += 5; /* type and CRC */
32874aea 1273 pad = 8 - (len % 8);
374330e2 1274 biglen = len + pad;
1275
ff3187f6 1276 pkt->length = len - 5;
1277 if (pkt->maxlen < biglen) {
1278 pkt->maxlen = biglen;
1279 pkt->data = sresize(pkt->data, biglen + 4 + APIEXTRA, unsigned char);
374330e2 1280 }
ff3187f6 1281 pkt->body = pkt->data + 4 + pad + 1;
4ba9b64b 1282}
374330e2 1283
ff3187f6 1284static struct Packet *s_wrpkt_start(int type, int len)
32874aea 1285{
ff3187f6 1286 struct Packet *pkt = ssh_new_packet();
1287 ssh1_pktout_size(pkt, len);
1288 pkt->type = type;
9a10ecf4 1289 /* Initialise log omission state */
ff3187f6 1290 pkt->nblanks = 0;
1291 pkt->blanks = NULL;
1292 return pkt;
374330e2 1293}
1294
ff3187f6 1295static int s_wrpkt_prepare(Ssh ssh, struct Packet *pkt)
32874aea 1296{
fd7a4aad 1297 int pad, biglen, i;
374330e2 1298 unsigned long crc;
fd7a4aad 1299#ifdef __SC__
1300 /*
1301 * XXX various versions of SC (including 8.8.4) screw up the
1302 * register allocation in this function and use the same register
1303 * (D6) for len and as a temporary, with predictable results. The
1304 * following sledgehammer prevents this.
1305 */
1306 volatile
1307#endif
1308 int len;
374330e2 1309
ff3187f6 1310 pkt->body[-1] = pkt->type;
4ba9b64b 1311
a8327734 1312 if (ssh->logctx)
ff3187f6 1313 log_packet(ssh->logctx, PKT_OUTGOING, pkt->type,
1314 ssh1_pkt_type(pkt->type),
1315 pkt->body, pkt->length,
1316 pkt->nblanks, pkt->blanks);
1317 sfree(pkt->blanks); pkt->blanks = NULL;
1318 pkt->nblanks = 0;
00db133f 1319
51470298 1320 if (ssh->v1_compressing) {
4ba9b64b 1321 unsigned char *compblk;
1322 int complen;
5366aed8 1323 zlib_compress_block(ssh->cs_comp_ctx,
ff3187f6 1324 pkt->body - 1, pkt->length + 1,
4ba9b64b 1325 &compblk, &complen);
ff3187f6 1326 ssh1_pktout_size(pkt, complen - 1);
1327 memcpy(pkt->body - 1, compblk, complen);
dcbde236 1328 sfree(compblk);
4ba9b64b 1329 }
1330
ff3187f6 1331 len = pkt->length + 5; /* type and CRC */
32874aea 1332 pad = 8 - (len % 8);
374330e2 1333 biglen = len + pad;
1334
32874aea 1335 for (i = 0; i < pad; i++)
ff3187f6 1336 pkt->data[i + 4] = random_byte();
1337 crc = crc32_compute(pkt->data + 4, biglen - 4);
1338 PUT_32BIT(pkt->data + biglen, crc);
1339 PUT_32BIT(pkt->data, len);
374330e2 1340
51470298 1341 if (ssh->cipher)
ff3187f6 1342 ssh->cipher->encrypt(ssh->v1_cipher_ctx, pkt->data + 4, biglen);
374330e2 1343
32874aea 1344 return biglen + 4;
39065bed 1345}
1346
ff3187f6 1347static void s_wrpkt(Ssh ssh, struct Packet *pkt)
32874aea 1348{
5471d09a 1349 int len, backlog;
ff3187f6 1350 len = s_wrpkt_prepare(ssh, pkt);
1351 backlog = sk_write(ssh->s, (char *)pkt->data, len);
5471d09a 1352 if (backlog > SSH_MAX_BACKLOG)
51470298 1353 ssh_throttle_all(ssh, 1, backlog);
39065bed 1354}
1355
ff3187f6 1356static void s_wrpkt_defer(Ssh ssh, struct Packet *pkt)
32874aea 1357{
39065bed 1358 int len;
ff3187f6 1359 len = s_wrpkt_prepare(ssh, pkt);
51470298 1360 if (ssh->deferred_len + len > ssh->deferred_size) {
1361 ssh->deferred_size = ssh->deferred_len + len + 128;
3d88e64d 1362 ssh->deferred_send_data = sresize(ssh->deferred_send_data,
1363 ssh->deferred_size,
1364 unsigned char);
39065bed 1365 }
ff3187f6 1366 memcpy(ssh->deferred_send_data + ssh->deferred_len, pkt->data, len);
51470298 1367 ssh->deferred_len += len;
374330e2 1368}
1369
fb09bf1c 1370/*
39065bed 1371 * Construct a packet with the specified contents.
fb09bf1c 1372 */
ff3187f6 1373static struct Packet *construct_packet(Ssh ssh, int pkttype,
1374 va_list ap1, va_list ap2)
fb09bf1c 1375{
fb09bf1c 1376 unsigned char *p, *argp, argchar;
1377 unsigned long argint;
1378 int pktlen, argtype, arglen;
7cca0d81 1379 Bignum bn;
ff3187f6 1380 struct Packet *pkt;
fb09bf1c 1381
1382 pktlen = 0;
39065bed 1383 while ((argtype = va_arg(ap1, int)) != PKT_END) {
fb09bf1c 1384 switch (argtype) {
1385 case PKT_INT:
39065bed 1386 (void) va_arg(ap1, int);
fb09bf1c 1387 pktlen += 4;
1388 break;
1389 case PKT_CHAR:
1ec39246 1390 (void) va_arg(ap1, int);
fb09bf1c 1391 pktlen++;
1392 break;
1393 case PKT_DATA:
39065bed 1394 (void) va_arg(ap1, unsigned char *);
1395 arglen = va_arg(ap1, int);
fb09bf1c 1396 pktlen += arglen;
1397 break;
1398 case PKT_STR:
39065bed 1399 argp = va_arg(ap1, unsigned char *);
d8baa528 1400 arglen = strlen((char *)argp);
fb09bf1c 1401 pktlen += 4 + arglen;
1402 break;
7cca0d81 1403 case PKT_BIGNUM:
39065bed 1404 bn = va_arg(ap1, Bignum);
32874aea 1405 pktlen += ssh1_bignum_length(bn);
7cca0d81 1406 break;
9a10ecf4 1407 case PKTT_PASSWORD:
1408 case PKTT_DATA:
1409 case PKTT_OTHER:
1410 /* ignore this pass */
1411 break;
fb09bf1c 1412 default:
1413 assert(0);
1414 }
1415 }
fb09bf1c 1416
ff3187f6 1417 pkt = s_wrpkt_start(pkttype, pktlen);
1418 p = pkt->body;
fb09bf1c 1419
39065bed 1420 while ((argtype = va_arg(ap2, int)) != PKT_END) {
ff3187f6 1421 int offset = p - pkt->body, len = 0;
fb09bf1c 1422 switch (argtype) {
9a10ecf4 1423 /* Actual fields in the packet */
fb09bf1c 1424 case PKT_INT:
39065bed 1425 argint = va_arg(ap2, int);
fb09bf1c 1426 PUT_32BIT(p, argint);
9a10ecf4 1427 len = 4;
fb09bf1c 1428 break;
1429 case PKT_CHAR:
1ec39246 1430 argchar = (unsigned char) va_arg(ap2, int);
fb09bf1c 1431 *p = argchar;
9a10ecf4 1432 len = 1;
fb09bf1c 1433 break;
1434 case PKT_DATA:
39065bed 1435 argp = va_arg(ap2, unsigned char *);
1436 arglen = va_arg(ap2, int);
fb09bf1c 1437 memcpy(p, argp, arglen);
9a10ecf4 1438 len = arglen;
fb09bf1c 1439 break;
1440 case PKT_STR:
39065bed 1441 argp = va_arg(ap2, unsigned char *);
d8baa528 1442 arglen = strlen((char *)argp);
fb09bf1c 1443 PUT_32BIT(p, arglen);
1444 memcpy(p + 4, argp, arglen);
9a10ecf4 1445 len = arglen + 4;
fb09bf1c 1446 break;
7cca0d81 1447 case PKT_BIGNUM:
39065bed 1448 bn = va_arg(ap2, Bignum);
9a10ecf4 1449 len = ssh1_write_bignum(p, bn);
1450 break;
1451 /* Tokens for modifications to packet logging */
1452 case PKTT_PASSWORD:
ff3187f6 1453 dont_log_password(ssh, pkt, PKTLOG_BLANK);
9a10ecf4 1454 break;
1455 case PKTT_DATA:
ff3187f6 1456 dont_log_data(ssh, pkt, PKTLOG_OMIT);
7cca0d81 1457 break;
9a10ecf4 1458 case PKTT_OTHER:
ff3187f6 1459 end_log_omission(ssh, pkt);
9a10ecf4 1460 break;
1461 }
1462 p += len;
1463 /* Deal with logfile omission, if required. */
ff3187f6 1464 if (len && (pkt->logmode != PKTLOG_EMIT)) {
1465 pkt->nblanks++;
1466 pkt->blanks = sresize(pkt->blanks, pkt->nblanks,
1467 struct logblank_t);
1468 pkt->blanks[pkt->nblanks-1].offset = offset;
1469 pkt->blanks[pkt->nblanks-1].len = len;
1470 pkt->blanks[pkt->nblanks-1].type = pkt->logmode;
fb09bf1c 1471 }
1472 }
ff3187f6 1473
1474 return pkt;
39065bed 1475}
fb09bf1c 1476
51470298 1477static void send_packet(Ssh ssh, int pkttype, ...)
32874aea 1478{
ff3187f6 1479 struct Packet *pkt;
39065bed 1480 va_list ap1, ap2;
1481 va_start(ap1, pkttype);
1482 va_start(ap2, pkttype);
ff3187f6 1483 pkt = construct_packet(ssh, pkttype, ap1, ap2);
1484 va_end(ap2);
1485 va_end(ap1);
1486 s_wrpkt(ssh, pkt);
1487 ssh_free_packet(pkt);
fb09bf1c 1488}
1489
51470298 1490static void defer_packet(Ssh ssh, int pkttype, ...)
32874aea 1491{
ff3187f6 1492 struct Packet *pkt;
39065bed 1493 va_list ap1, ap2;
1494 va_start(ap1, pkttype);
1495 va_start(ap2, pkttype);
ff3187f6 1496 pkt = construct_packet(ssh, pkttype, ap1, ap2);
1497 va_end(ap2);
1498 va_end(ap1);
1499 s_wrpkt_defer(ssh, pkt);
1500 ssh_free_packet(pkt);
39065bed 1501}
1502
32874aea 1503static int ssh_versioncmp(char *a, char *b)
1504{
9697bfd2 1505 char *ae, *be;
1506 unsigned long av, bv;
1507
43aa02a7 1508 av = strtoul(a, &ae, 10);
1509 bv = strtoul(b, &be, 10);
32874aea 1510 if (av != bv)
1511 return (av < bv ? -1 : +1);
1512 if (*ae == '.')
1513 ae++;
1514 if (*be == '.')
1515 be++;
43aa02a7 1516 av = strtoul(ae, &ae, 10);
1517 bv = strtoul(be, &be, 10);
32874aea 1518 if (av != bv)
1519 return (av < bv ? -1 : +1);
9697bfd2 1520 return 0;
1521}
1522
e5574168 1523/*
a92dd380 1524 * Utility routines for putting an SSH-protocol `string' and
1525 * `uint32' into a SHA state.
e5574168 1526 */
1527#include <stdio.h>
32874aea 1528static void sha_string(SHA_State * s, void *str, int len)
1529{
e5574168 1530 unsigned char lenblk[4];
e5574168 1531 PUT_32BIT(lenblk, len);
e5574168 1532 SHA_Bytes(s, lenblk, 4);
e5574168 1533 SHA_Bytes(s, str, len);
1534}
1535
32874aea 1536static void sha_uint32(SHA_State * s, unsigned i)
1537{
a92dd380 1538 unsigned char intblk[4];
1539 PUT_32BIT(intblk, i);
1540 SHA_Bytes(s, intblk, 4);
1541}
1542
7cca0d81 1543/*
1544 * SSH2 packet construction functions.
1545 */
ff3187f6 1546static void ssh2_pkt_ensure(struct Packet *pkt, int length)
32874aea 1547{
ff3187f6 1548 if (pkt->maxlen < length) {
1549 pkt->maxlen = length + 256;
1550 pkt->data = sresize(pkt->data, pkt->maxlen + APIEXTRA, unsigned char);
7cca0d81 1551 }
783415f8 1552}
ff3187f6 1553static void ssh2_pkt_adddata(struct Packet *pkt, void *data, int len)
32874aea 1554{
ff3187f6 1555 if (pkt->logmode != PKTLOG_EMIT) {
1556 pkt->nblanks++;
1557 pkt->blanks = sresize(pkt->blanks, pkt->nblanks, struct logblank_t);
1558 pkt->blanks[pkt->nblanks-1].offset = pkt->length - 6;
1559 pkt->blanks[pkt->nblanks-1].len = len;
1560 pkt->blanks[pkt->nblanks-1].type = pkt->logmode;
1561 }
1562 pkt->length += len;
1563 ssh2_pkt_ensure(pkt, pkt->length);
1564 memcpy(pkt->data + pkt->length - len, data, len);
7cca0d81 1565}
ff3187f6 1566static void ssh2_pkt_addbyte(struct Packet *pkt, unsigned char byte)
32874aea 1567{
ff3187f6 1568 ssh2_pkt_adddata(pkt, &byte, 1);
7cca0d81 1569}
ff3187f6 1570static struct Packet *ssh2_pkt_init(int pkt_type)
32874aea 1571{
ff3187f6 1572 struct Packet *pkt = ssh_new_packet();
1573 pkt->length = 5;
1574 ssh2_pkt_addbyte(pkt, (unsigned char) pkt_type);
1575 return pkt;
7cca0d81 1576}
ff3187f6 1577static void ssh2_pkt_addbool(struct Packet *pkt, unsigned char value)
32874aea 1578{
ff3187f6 1579 ssh2_pkt_adddata(pkt, &value, 1);
7cca0d81 1580}
ff3187f6 1581static void ssh2_pkt_adduint32(struct Packet *pkt, unsigned long value)
32874aea 1582{
7cca0d81 1583 unsigned char x[4];
1584 PUT_32BIT(x, value);
ff3187f6 1585 ssh2_pkt_adddata(pkt, x, 4);
7cca0d81 1586}
ff3187f6 1587static void ssh2_pkt_addstring_start(struct Packet *pkt)
32874aea 1588{
ff3187f6 1589 ssh2_pkt_adduint32(pkt, 0);
1590 pkt->savedpos = pkt->length;
7cca0d81 1591}
ff3187f6 1592static void ssh2_pkt_addstring_str(struct Packet *pkt, char *data)
32874aea 1593{
ff3187f6 1594 ssh2_pkt_adddata(pkt, data, strlen(data));
1595 PUT_32BIT(pkt->data + pkt->savedpos - 4, pkt->length - pkt->savedpos);
7cca0d81 1596}
ff3187f6 1597static void ssh2_pkt_addstring_data(struct Packet *pkt, char *data, int len)
32874aea 1598{
ff3187f6 1599 ssh2_pkt_adddata(pkt, data, len);
1600 PUT_32BIT(pkt->data + pkt->savedpos - 4, pkt->length - pkt->savedpos);
7cca0d81 1601}
ff3187f6 1602static void ssh2_pkt_addstring(struct Packet *pkt, char *data)
32874aea 1603{
ff3187f6 1604 ssh2_pkt_addstring_start(pkt);
1605 ssh2_pkt_addstring_str(pkt, data);
7cca0d81 1606}
d8baa528 1607static unsigned char *ssh2_mpint_fmt(Bignum b, int *len)
32874aea 1608{
7cca0d81 1609 unsigned char *p;
32874aea 1610 int i, n = (bignum_bitcount(b) + 7) / 8;
3d88e64d 1611 p = snewn(n + 1, unsigned char);
7cca0d81 1612 if (!p)
32874aea 1613 fatalbox("out of memory");
7cca0d81 1614 p[0] = 0;
3709bfe9 1615 for (i = 1; i <= n; i++)
32874aea 1616 p[i] = bignum_byte(b, n - i);
7cca0d81 1617 i = 0;
32874aea 1618 while (i <= n && p[i] == 0 && (p[i + 1] & 0x80) == 0)
1619 i++;
1620 memmove(p, p + i, n + 1 - i);
1621 *len = n + 1 - i;
7cca0d81 1622 return p;
1623}
ff3187f6 1624static void ssh2_pkt_addmp(struct Packet *pkt, Bignum b)
32874aea 1625{
7cca0d81 1626 unsigned char *p;
1627 int len;
1628 p = ssh2_mpint_fmt(b, &len);
ff3187f6 1629 ssh2_pkt_addstring_start(pkt);
1630 ssh2_pkt_addstring_data(pkt, (char *)p, len);
dcbde236 1631 sfree(p);
7cca0d81 1632}
b185170a 1633
1634/*
1635 * Construct an SSH2 final-form packet: compress it, encrypt it,
1636 * put the MAC on it. Final packet, ready to be sent, is stored in
ff3187f6 1637 * pkt->data. Total length is returned.
b185170a 1638 */
ff3187f6 1639static int ssh2_pkt_construct(Ssh ssh, struct Packet *pkt)
32874aea 1640{
7cca0d81 1641 int cipherblk, maclen, padding, i;
7cca0d81 1642
a8327734 1643 if (ssh->logctx)
ff3187f6 1644 log_packet(ssh->logctx, PKT_OUTGOING, pkt->data[5],
1645 ssh2_pkt_type(ssh->pkt_ctx, pkt->data[5]),
1646 pkt->data + 6, pkt->length - 6,
1647 pkt->nblanks, pkt->blanks);
1648 sfree(pkt->blanks); pkt->blanks = NULL;
1649 pkt->nblanks = 0;
00db133f 1650
7cca0d81 1651 /*
4ba9b64b 1652 * Compress packet payload.
1653 */
4ba9b64b 1654 {
1655 unsigned char *newpayload;
1656 int newlen;
51470298 1657 if (ssh->cscomp &&
ff3187f6 1658 ssh->cscomp->compress(ssh->cs_comp_ctx, pkt->data + 5,
1659 pkt->length - 5,
51470298 1660 &newpayload, &newlen)) {
ff3187f6 1661 pkt->length = 5;
1662 ssh2_pkt_adddata(pkt, newpayload, newlen);
dcbde236 1663 sfree(newpayload);
4ba9b64b 1664 }
1665 }
1666
1667 /*
7cca0d81 1668 * Add padding. At least four bytes, and must also bring total
1669 * length (minus MAC) up to a multiple of the block size.
1670 */
51470298 1671 cipherblk = ssh->cscipher ? ssh->cscipher->blksize : 8; /* block size */
32874aea 1672 cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
7cca0d81 1673 padding = 4;
32874aea 1674 padding +=
ff3187f6 1675 (cipherblk - (pkt->length + padding) % cipherblk) % cipherblk;
51470298 1676 maclen = ssh->csmac ? ssh->csmac->len : 0;
ff3187f6 1677 ssh2_pkt_ensure(pkt, pkt->length + padding + maclen);
1678 pkt->data[4] = padding;
7cca0d81 1679 for (i = 0; i < padding; i++)
ff3187f6 1680 pkt->data[pkt->length + i] = random_byte();
1681 PUT_32BIT(pkt->data, pkt->length + padding - 4);
51470298 1682 if (ssh->csmac)
ff3187f6 1683 ssh->csmac->generate(ssh->cs_mac_ctx, pkt->data,
1684 pkt->length + padding,
51470298 1685 ssh->v2_outgoing_sequence);
1686 ssh->v2_outgoing_sequence++; /* whether or not we MACed */
1687
1688 if (ssh->cscipher)
371e569c 1689 ssh->cscipher->encrypt(ssh->cs_cipher_ctx,
ff3187f6 1690 pkt->data, pkt->length + padding);
51470298 1691
9442dd57 1692 pkt->encrypted_len = pkt->length + padding;
1693
ff3187f6 1694 /* Ready-to-send packet starts at pkt->data. We return length. */
1695 return pkt->length + padding + maclen;
b185170a 1696}
1697
1698/*
590f6a5f 1699 * Routines called from the main SSH code to send packets. There
1700 * are quite a few of these, because we have two separate
1701 * mechanisms for delaying the sending of packets:
1702 *
1703 * - In order to send an IGNORE message and a password message in
1704 * a single fixed-length blob, we require the ability to
1705 * concatenate the encrypted forms of those two packets _into_ a
1706 * single blob and then pass it to our <network.h> transport
1707 * layer in one go. Hence, there's a deferment mechanism which
1708 * works after packet encryption.
1709 *
1710 * - In order to avoid sending any connection-layer messages
1711 * during repeat key exchange, we have to queue up any such
1712 * outgoing messages _before_ they are encrypted (and in
1713 * particular before they're allocated sequence numbers), and
1714 * then send them once we've finished.
1715 *
1716 * I call these mechanisms `defer' and `queue' respectively, so as
1717 * to distinguish them reasonably easily.
1718 *
1719 * The functions send_noqueue() and defer_noqueue() free the packet
1720 * structure they are passed. Every outgoing packet goes through
1721 * precisely one of these functions in its life; packets passed to
1722 * ssh2_pkt_send() or ssh2_pkt_defer() either go straight to one of
1723 * these or get queued, and then when the queue is later emptied
1724 * the packets are all passed to defer_noqueue().
b185170a 1725 */
590f6a5f 1726
1727/*
1728 * Send an SSH2 packet immediately, without queuing or deferring.
1729 */
1730static void ssh2_pkt_send_noqueue(Ssh ssh, struct Packet *pkt)
32874aea 1731{
5471d09a 1732 int len;
1733 int backlog;
ff3187f6 1734 len = ssh2_pkt_construct(ssh, pkt);
1735 backlog = sk_write(ssh->s, (char *)pkt->data, len);
5471d09a 1736 if (backlog > SSH_MAX_BACKLOG)
51470298 1737 ssh_throttle_all(ssh, 1, backlog);
9442dd57 1738
1739 ssh->outgoing_data_size += pkt->encrypted_len;
1740 if (!ssh->kex_in_progress &&
d57f70af 1741 ssh->max_data_size != 0 &&
1742 ssh->outgoing_data_size > ssh->max_data_size)
f382c87d 1743 do_ssh2_transport(ssh, "too much data sent", -1, NULL);
9442dd57 1744
ff3187f6 1745 ssh_free_packet(pkt);
b185170a 1746}
1747
1748/*
590f6a5f 1749 * Defer an SSH2 packet.
b185170a 1750 */
590f6a5f 1751static void ssh2_pkt_defer_noqueue(Ssh ssh, struct Packet *pkt)
32874aea 1752{
ff3187f6 1753 int len = ssh2_pkt_construct(ssh, pkt);
51470298 1754 if (ssh->deferred_len + len > ssh->deferred_size) {
1755 ssh->deferred_size = ssh->deferred_len + len + 128;
3d88e64d 1756 ssh->deferred_send_data = sresize(ssh->deferred_send_data,
1757 ssh->deferred_size,
1758 unsigned char);
b185170a 1759 }
ff3187f6 1760 memcpy(ssh->deferred_send_data + ssh->deferred_len, pkt->data, len);
51470298 1761 ssh->deferred_len += len;
9442dd57 1762 ssh->deferred_data_size += pkt->encrypted_len;
ff3187f6 1763 ssh_free_packet(pkt);
b185170a 1764}
1765
1766/*
590f6a5f 1767 * Queue an SSH2 packet.
1768 */
1769static void ssh2_pkt_queue(Ssh ssh, struct Packet *pkt)
1770{
1771 assert(ssh->queueing);
1772
1773 if (ssh->queuelen >= ssh->queuesize) {
1774 ssh->queuesize = ssh->queuelen + 32;
1775 ssh->queue = sresize(ssh->queue, ssh->queuesize, struct Packet *);
1776 }
1777
1778 ssh->queue[ssh->queuelen++] = pkt;
1779}
1780
1781/*
1782 * Either queue or send a packet, depending on whether queueing is
1783 * set.
1784 */
1785static void ssh2_pkt_send(Ssh ssh, struct Packet *pkt)
1786{
1787 if (ssh->queueing)
1788 ssh2_pkt_queue(ssh, pkt);
1789 else
1790 ssh2_pkt_send_noqueue(ssh, pkt);
1791}
1792
1793/*
1794 * Either queue or defer a packet, depending on whether queueing is
1795 * set.
1796 */
1797static void ssh2_pkt_defer(Ssh ssh, struct Packet *pkt)
1798{
1799 if (ssh->queueing)
1800 ssh2_pkt_queue(ssh, pkt);
1801 else
1802 ssh2_pkt_defer_noqueue(ssh, pkt);
1803}
1804
1805/*
b185170a 1806 * Send the whole deferred data block constructed by
39065bed 1807 * ssh2_pkt_defer() or SSH1's defer_packet().
590f6a5f 1808 *
1809 * The expected use of the defer mechanism is that you call
1810 * ssh2_pkt_defer() a few times, then call ssh_pkt_defersend(). If
1811 * not currently queueing, this simply sets up deferred_send_data
1812 * and then sends it. If we _are_ currently queueing, the calls to
1813 * ssh2_pkt_defer() put the deferred packets on to the queue
1814 * instead, and therefore ssh_pkt_defersend() has no deferred data
1815 * to send. Hence, there's no need to make it conditional on
1816 * ssh->queueing.
b185170a 1817 */
51470298 1818static void ssh_pkt_defersend(Ssh ssh)
32874aea 1819{
5471d09a 1820 int backlog;
d8baa528 1821 backlog = sk_write(ssh->s, (char *)ssh->deferred_send_data,
1822 ssh->deferred_len);
51470298 1823 ssh->deferred_len = ssh->deferred_size = 0;
1824 sfree(ssh->deferred_send_data);
1825 ssh->deferred_send_data = NULL;
5471d09a 1826 if (backlog > SSH_MAX_BACKLOG)
51470298 1827 ssh_throttle_all(ssh, 1, backlog);
9442dd57 1828
1829 ssh->outgoing_data_size += ssh->deferred_data_size;
1830 if (!ssh->kex_in_progress &&
d57f70af 1831 ssh->max_data_size != 0 &&
1832 ssh->outgoing_data_size > ssh->max_data_size)
f382c87d 1833 do_ssh2_transport(ssh, "too much data sent", -1, NULL);
9442dd57 1834 ssh->deferred_data_size = 0;
7cca0d81 1835}
1836
590f6a5f 1837/*
1838 * Send all queued SSH2 packets. We send them by means of
1839 * ssh2_pkt_defer_noqueue(), in case they included a pair of
1840 * packets that needed to be lumped together.
1841 */
1842static void ssh2_pkt_queuesend(Ssh ssh)
1843{
1844 int i;
1845
1846 assert(!ssh->queueing);
1847
1848 for (i = 0; i < ssh->queuelen; i++)
1849 ssh2_pkt_defer_noqueue(ssh, ssh->queue[i]);
1850 ssh->queuelen = 0;
1851
1852 ssh_pkt_defersend(ssh);
1853}
1854
7cca0d81 1855#if 0
32874aea 1856void bndebug(char *string, Bignum b)
1857{
7cca0d81 1858 unsigned char *p;
1859 int i, len;
1860 p = ssh2_mpint_fmt(b, &len);
1861 debug(("%s", string));
1862 for (i = 0; i < len; i++)
32874aea 1863 debug((" %02x", p[i]));
765c4200 1864 debug(("\n"));
dcbde236 1865 sfree(p);
7cca0d81 1866}
1867#endif
1868
32874aea 1869static void sha_mpint(SHA_State * s, Bignum b)
1870{
7cca0d81 1871 unsigned char *p;
1872 int len;
1873 p = ssh2_mpint_fmt(b, &len);
1874 sha_string(s, p, len);
dcbde236 1875 sfree(p);
7cca0d81 1876}
1877
1878/*
0016d70b 1879 * Packet decode functions for both SSH1 and SSH2.
7cca0d81 1880 */
ff3187f6 1881static unsigned long ssh_pkt_getuint32(struct Packet *pkt)
32874aea 1882{
7cca0d81 1883 unsigned long value;
ff3187f6 1884 if (pkt->length - pkt->savedpos < 4)
32874aea 1885 return 0; /* arrgh, no way to decline (FIXME?) */
ff3187f6 1886 value = GET_32BIT(pkt->body + pkt->savedpos);
1887 pkt->savedpos += 4;
7cca0d81 1888 return value;
1889}
ff3187f6 1890static int ssh2_pkt_getbool(struct Packet *pkt)
32874aea 1891{
65a22376 1892 unsigned long value;
ff3187f6 1893 if (pkt->length - pkt->savedpos < 1)
32874aea 1894 return 0; /* arrgh, no way to decline (FIXME?) */
ff3187f6 1895 value = pkt->body[pkt->savedpos] != 0;
1896 pkt->savedpos++;
65a22376 1897 return value;
1898}
ff3187f6 1899static void ssh_pkt_getstring(struct Packet *pkt, char **p, int *length)
32874aea 1900{
57356d63 1901 int len;
7cca0d81 1902 *p = NULL;
45068b27 1903 *length = 0;
ff3187f6 1904 if (pkt->length - pkt->savedpos < 4)
32874aea 1905 return;
ff3187f6 1906 len = GET_32BIT(pkt->body + pkt->savedpos);
57356d63 1907 if (len < 0)
1908 return;
1909 *length = len;
ff3187f6 1910 pkt->savedpos += 4;
1911 if (pkt->length - pkt->savedpos < *length)
32874aea 1912 return;
ff3187f6 1913 *p = (char *)(pkt->body + pkt->savedpos);
1914 pkt->savedpos += *length;
7cca0d81 1915}
ff3187f6 1916static void *ssh_pkt_getdata(struct Packet *pkt, int length)
0016d70b 1917{
ff3187f6 1918 if (pkt->length - pkt->savedpos < length)
0016d70b 1919 return NULL;
ff3187f6 1920 pkt->savedpos += length;
1921 return pkt->body + (pkt->savedpos - length);
0016d70b 1922}
ff3187f6 1923static int ssh1_pkt_getrsakey(struct Packet *pkt, struct RSAKey *key,
0016d70b 1924 unsigned char **keystr)
1925{
1926 int j;
1927
ff3187f6 1928 j = makekey(pkt->body + pkt->savedpos,
1929 pkt->length - pkt->savedpos,
0016d70b 1930 key, keystr, 0);
1931
1932 if (j < 0)
1933 return FALSE;
1934
ff3187f6 1935 pkt->savedpos += j;
1936 assert(pkt->savedpos < pkt->length);
0016d70b 1937
1938 return TRUE;
1939}
ff3187f6 1940static Bignum ssh1_pkt_getmp(struct Packet *pkt)
0016d70b 1941{
1942 int j;
1943 Bignum b;
1944
ff3187f6 1945 j = ssh1_read_bignum(pkt->body + pkt->savedpos,
1946 pkt->length - pkt->savedpos, &b);
0016d70b 1947
1948 if (j < 0)
1949 return NULL;
1950
ff3187f6 1951 pkt->savedpos += j;
0016d70b 1952 return b;
1953}
ff3187f6 1954static Bignum ssh2_pkt_getmp(struct Packet *pkt)
32874aea 1955{
7cca0d81 1956 char *p;
3709bfe9 1957 int length;
7cca0d81 1958 Bignum b;
1959
ff3187f6 1960 ssh_pkt_getstring(pkt, &p, &length);
7cca0d81 1961 if (!p)
32874aea 1962 return NULL;
ff3187f6 1963 if (p[0] & 0x80)
32874aea 1964 return NULL;
d8baa528 1965 b = bignum_from_bytes((unsigned char *)p, length);
7cca0d81 1966 return b;
1967}
1968
7d503c31 1969/*
1dd353b5 1970 * Helper function to add an SSH2 signature blob to a packet.
1971 * Expects to be shown the public key blob as well as the signature
1972 * blob. Normally works just like ssh2_pkt_addstring, but will
1973 * fiddle with the signature packet if necessary for
1974 * BUG_SSH2_RSA_PADDING.
1975 */
ff3187f6 1976static void ssh2_add_sigblob(Ssh ssh, struct Packet *pkt,
1977 void *pkblob_v, int pkblob_len,
1dd353b5 1978 void *sigblob_v, int sigblob_len)
1979{
1980 unsigned char *pkblob = (unsigned char *)pkblob_v;
1981 unsigned char *sigblob = (unsigned char *)sigblob_v;
1982
1983 /* dmemdump(pkblob, pkblob_len); */
1984 /* dmemdump(sigblob, sigblob_len); */
1985
1986 /*
1987 * See if this is in fact an ssh-rsa signature and a buggy
1988 * server; otherwise we can just do this the easy way.
1989 */
51470298 1990 if ((ssh->remote_bugs & BUG_SSH2_RSA_PADDING) &&
1dd353b5 1991 (GET_32BIT(pkblob) == 7 && !memcmp(pkblob+4, "ssh-rsa", 7))) {
1992 int pos, len, siglen;
1993
1994 /*
1995 * Find the byte length of the modulus.
1996 */
1997
1998 pos = 4+7; /* skip over "ssh-rsa" */
1999 pos += 4 + GET_32BIT(pkblob+pos); /* skip over exponent */
2000 len = GET_32BIT(pkblob+pos); /* find length of modulus */
2001 pos += 4; /* find modulus itself */
2002 while (len > 0 && pkblob[pos] == 0)
2003 len--, pos++;
2004 /* debug(("modulus length is %d\n", len)); */
2005
2006 /*
2007 * Now find the signature integer.
2008 */
2009 pos = 4+7; /* skip over "ssh-rsa" */
2010 siglen = GET_32BIT(sigblob+pos);
2011 /* debug(("signature length is %d\n", siglen)); */
2012
2013 if (len != siglen) {
2014 unsigned char newlen[4];
ff3187f6 2015 ssh2_pkt_addstring_start(pkt);
2016 ssh2_pkt_addstring_data(pkt, (char *)sigblob, pos);
1dd353b5 2017 /* dmemdump(sigblob, pos); */
2018 pos += 4; /* point to start of actual sig */
2019 PUT_32BIT(newlen, len);
ff3187f6 2020 ssh2_pkt_addstring_data(pkt, (char *)newlen, 4);
1dd353b5 2021 /* dmemdump(newlen, 4); */
2022 newlen[0] = 0;
2023 while (len-- > siglen) {
ff3187f6 2024 ssh2_pkt_addstring_data(pkt, (char *)newlen, 1);
1dd353b5 2025 /* dmemdump(newlen, 1); */
2026 }
ff3187f6 2027 ssh2_pkt_addstring_data(pkt, (char *)(sigblob+pos), siglen);
1dd353b5 2028 /* dmemdump(sigblob+pos, siglen); */
2029 return;
2030 }
2031
2032 /* Otherwise fall through and do it the easy way. */
2033 }
2034
ff3187f6 2035 ssh2_pkt_addstring_start(pkt);
2036 ssh2_pkt_addstring_data(pkt, (char *)sigblob, sigblob_len);
1dd353b5 2037}
2038
2039/*
7d503c31 2040 * Examine the remote side's version string and compare it against
2041 * a list of known buggy implementations.
2042 */
51470298 2043static void ssh_detect_bugs(Ssh ssh, char *vstring)
32874aea 2044{
2045 char *imp; /* pointer to implementation part */
7d503c31 2046 imp = vstring;
2047 imp += strcspn(imp, "-");
bd358db1 2048 if (*imp) imp++;
7d503c31 2049 imp += strcspn(imp, "-");
bd358db1 2050 if (*imp) imp++;
7d503c31 2051
51470298 2052 ssh->remote_bugs = 0;
7d503c31 2053
5ecd7ad0 2054 if (ssh->cfg.sshbug_ignore1 == FORCE_ON ||
2055 (ssh->cfg.sshbug_ignore1 == AUTO &&
2c9c6388 2056 (!strcmp(imp, "1.2.18") || !strcmp(imp, "1.2.19") ||
2057 !strcmp(imp, "1.2.20") || !strcmp(imp, "1.2.21") ||
46ac09aa 2058 !strcmp(imp, "1.2.22") || !strcmp(imp, "Cisco-1.25") ||
bd0b4caf 2059 !strcmp(imp, "OSU_1.4alpha3") || !strcmp(imp, "OSU_1.5alpha4")))) {
32874aea 2060 /*
2061 * These versions don't support SSH1_MSG_IGNORE, so we have
2062 * to use a different defence against password length
2063 * sniffing.
2064 */
51470298 2065 ssh->remote_bugs |= BUG_CHOKES_ON_SSH1_IGNORE;
32874aea 2066 logevent("We believe remote version has SSH1 ignore bug");
7d503c31 2067 }
2068
5ecd7ad0 2069 if (ssh->cfg.sshbug_plainpw1 == FORCE_ON ||
2070 (ssh->cfg.sshbug_plainpw1 == AUTO &&
46ac09aa 2071 (!strcmp(imp, "Cisco-1.25") || !strcmp(imp, "OSU_1.4alpha3")))) {
bd358db1 2072 /*
2073 * These versions need a plain password sent; they can't
2074 * handle having a null and a random length of data after
2075 * the password.
2076 */
51470298 2077 ssh->remote_bugs |= BUG_NEEDS_SSH1_PLAIN_PASSWORD;
bd358db1 2078 logevent("We believe remote version needs a plain SSH1 password");
2079 }
2080
5ecd7ad0 2081 if (ssh->cfg.sshbug_rsa1 == FORCE_ON ||
2082 (ssh->cfg.sshbug_rsa1 == AUTO &&
2c9c6388 2083 (!strcmp(imp, "Cisco-1.25")))) {
0df73905 2084 /*
2085 * These versions apparently have no clue whatever about
2086 * RSA authentication and will panic and die if they see
2087 * an AUTH_RSA message.
2088 */
51470298 2089 ssh->remote_bugs |= BUG_CHOKES_ON_RSA;
0df73905 2090 logevent("We believe remote version can't handle RSA authentication");
2091 }
2092
5ecd7ad0 2093 if (ssh->cfg.sshbug_hmac2 == FORCE_ON ||
2094 (ssh->cfg.sshbug_hmac2 == AUTO &&
b9f387af 2095 !wc_match("* VShell", imp) &&
831301f6 2096 (wc_match("2.1.0*", imp) || wc_match("2.0.*", imp) ||
2097 wc_match("2.2.0*", imp) || wc_match("2.3.0*", imp) ||
2098 wc_match("2.1 *", imp)))) {
32874aea 2099 /*
2100 * These versions have the HMAC bug.
2101 */
51470298 2102 ssh->remote_bugs |= BUG_SSH2_HMAC;
32874aea 2103 logevent("We believe remote version has SSH2 HMAC bug");
7d503c31 2104 }
1dd353b5 2105
5ecd7ad0 2106 if (ssh->cfg.sshbug_derivekey2 == FORCE_ON ||
2107 (ssh->cfg.sshbug_derivekey2 == AUTO &&
b9f387af 2108 !wc_match("* VShell", imp) &&
2856a1b9 2109 (wc_match("2.0.0*", imp) || wc_match("2.0.10*", imp) ))) {
088bde77 2110 /*
2111 * These versions have the key-derivation bug (failing to
2112 * include the literal shared secret in the hashes that
2113 * generate the keys).
2114 */
51470298 2115 ssh->remote_bugs |= BUG_SSH2_DERIVEKEY;
088bde77 2116 logevent("We believe remote version has SSH2 key-derivation bug");
2117 }
2118
5ecd7ad0 2119 if (ssh->cfg.sshbug_rsapad2 == FORCE_ON ||
2120 (ssh->cfg.sshbug_rsapad2 == AUTO &&
831301f6 2121 (wc_match("OpenSSH_2.[5-9]*", imp) ||
2122 wc_match("OpenSSH_3.[0-2]*", imp)))) {
1dd353b5 2123 /*
2124 * These versions have the SSH2 RSA padding bug.
2125 */
51470298 2126 ssh->remote_bugs |= BUG_SSH2_RSA_PADDING;
1dd353b5 2127 logevent("We believe remote version has SSH2 RSA padding bug");
2128 }
8e975795 2129
dda87a28 2130 if (ssh->cfg.sshbug_pksessid2 == FORCE_ON ||
2131 (ssh->cfg.sshbug_pksessid2 == AUTO &&
2132 wc_match("OpenSSH_2.[0-2]*", imp))) {
2133 /*
2134 * These versions have the SSH2 session-ID bug in
2135 * public-key authentication.
2136 */
2137 ssh->remote_bugs |= BUG_SSH2_PK_SESSIONID;
2138 logevent("We believe remote version has SSH2 public-key-session-ID bug");
2139 }
f382c87d 2140
2141 if (ssh->cfg.sshbug_rekey2 == FORCE_ON ||
2142 (ssh->cfg.sshbug_rekey2 == AUTO &&
e12d95a5 2143 (wc_match("OpenSSH_2.[0-4]*", imp) ||
2144 wc_match("OpenSSH_2.5.[0-3]*", imp) ||
2145 wc_match("Sun_SSH_1.0", imp) ||
7cb41bb2 2146 wc_match("Sun_SSH_1.0.1", imp)))) {
f382c87d 2147 /*
e12d95a5 2148 * These versions have the SSH2 rekey bug.
f382c87d 2149 */
2150 ssh->remote_bugs |= BUG_SSH2_REKEY;
e12d95a5 2151 logevent("We believe remote version has SSH2 rekey bug");
f382c87d 2152 }
7d503c31 2153}
2154
d38d6a1f 2155/*
2156 * The `software version' part of an SSH version string is required
2157 * to contain no spaces or minus signs.
2158 */
2159static void ssh_fix_verstring(char *str)
2160{
2161 /* Eat "SSH-<protoversion>-". */
2162 assert(*str == 'S'); str++;
2163 assert(*str == 'S'); str++;
2164 assert(*str == 'H'); str++;
2165 assert(*str == '-'); str++;
2166 while (*str && *str != '-') str++;
2167 assert(*str == '-'); str++;
2168
2169 /* Convert minus signs and spaces in the remaining string into
2170 * underscores. */
2171 while (*str) {
2172 if (*str == '-' || *str == ' ')
2173 *str = '_';
2174 str++;
2175 }
2176}
2177
51470298 2178static int do_ssh_init(Ssh ssh, unsigned char c)
32874aea 2179{
51470298 2180 struct do_ssh_init_state {
2181 int vslen;
2182 char version[10];
2183 char *vstring;
2184 int vstrsize;
2185 int i;
2186 int proto1, proto2;
2187 };
2188 crState(do_ssh_init_state);
374330e2 2189
51470298 2190 crBegin(ssh->do_ssh_init_crstate);
8df7a775 2191
2192 /* Search for the string "SSH-" in the input. */
51470298 2193 s->i = 0;
8df7a775 2194 while (1) {
2195 static const int transS[] = { 1, 2, 2, 1 };
2196 static const int transH[] = { 0, 0, 3, 0 };
2197 static const int transminus[] = { 0, 0, 0, -1 };
32874aea 2198 if (c == 'S')
51470298 2199 s->i = transS[s->i];
32874aea 2200 else if (c == 'H')
51470298 2201 s->i = transH[s->i];
32874aea 2202 else if (c == '-')
51470298 2203 s->i = transminus[s->i];
32874aea 2204 else
51470298 2205 s->i = 0;
2206 if (s->i < 0)
8df7a775 2207 break;
2208 crReturn(1); /* get another character */
374330e2 2209 }
8df7a775 2210
51470298 2211 s->vstrsize = 16;
3d88e64d 2212 s->vstring = snewn(s->vstrsize, char);
51470298 2213 strcpy(s->vstring, "SSH-");
2214 s->vslen = 4;
2215 s->i = 0;
374330e2 2216 while (1) {
8df7a775 2217 crReturn(1); /* get another char */
51470298 2218 if (s->vslen >= s->vstrsize - 1) {
2219 s->vstrsize += 16;
3d88e64d 2220 s->vstring = sresize(s->vstring, s->vstrsize, char);
32874aea 2221 }
51470298 2222 s->vstring[s->vslen++] = c;
2223 if (s->i >= 0) {
374330e2 2224 if (c == '-') {
51470298 2225 s->version[s->i] = '\0';
2226 s->i = -1;
2227 } else if (s->i < sizeof(s->version) - 1)
2228 s->version[s->i++] = c;
c4ffc4d0 2229 } else if (c == '\012')
374330e2 2230 break;
2231 }
2232
51470298 2233 ssh->agentfwd_enabled = FALSE;
2234 ssh->rdpkt2_state.incoming_sequence = 0;
960e736a 2235
51470298 2236 s->vstring[s->vslen] = 0;
a7d4653a 2237 s->vstring[strcspn(s->vstring, "\015\012")] = '\0';/* remove EOL chars */
51470298 2238 {
2239 char *vlog;
3d88e64d 2240 vlog = snewn(20 + s->vslen, char);
51470298 2241 sprintf(vlog, "Server version: %s", s->vstring);
2242 logevent(vlog);
2243 sfree(vlog);
2244 }
2245 ssh_detect_bugs(ssh, s->vstring);
c5e9c988 2246
adf799dd 2247 /*
38d228a2 2248 * Decide which SSH protocol version to support.
adf799dd 2249 */
38d228a2 2250
2251 /* Anything strictly below "2.0" means protocol 1 is supported. */
51470298 2252 s->proto1 = ssh_versioncmp(s->version, "2.0") < 0;
38d228a2 2253 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
51470298 2254 s->proto2 = ssh_versioncmp(s->version, "1.99") >= 0;
38d228a2 2255
86916870 2256 if (ssh->cfg.sshprot == 0 && !s->proto1) {
6b5cf8b4 2257 bombout(("SSH protocol version 1 required by user but not provided by server"));
7ffdbc1a 2258 crStop(0);
38d228a2 2259 }
86916870 2260 if (ssh->cfg.sshprot == 3 && !s->proto2) {
6b5cf8b4 2261 bombout(("SSH protocol version 2 required by user but not provided by server"));
7ffdbc1a 2262 crStop(0);
38d228a2 2263 }
2264
d38d6a1f 2265 {
2266 char *verstring;
2267
2268 if (s->proto2 && (ssh->cfg.sshprot >= 2 || !s->proto1)) {
2269 /*
2270 * Construct a v2 version string.
2271 */
a7d4653a 2272 verstring = dupprintf("SSH-2.0-%s\015\012", sshver);
d38d6a1f 2273 ssh->version = 2;
2274 } else {
2275 /*
2276 * Construct a v1 version string.
2277 */
a7d4653a 2278 verstring = dupprintf("SSH-%s-%s\012",
d38d6a1f 2279 (ssh_versioncmp(s->version, "1.5") <= 0 ?
2280 s->version : "1.5"),
2281 sshver);
2282 ssh->version = 1;
2283 }
2284
2285 ssh_fix_verstring(verstring);
2286
2287 if (ssh->version == 2) {
2288 /*
2289 * Hash our version string and their version string.
2290 */
2291 SHA_Init(&ssh->exhashbase);
0b351b6b 2292 sha_string(&ssh->exhashbase, verstring,
a7d4653a 2293 strcspn(verstring, "\015\012"));
0b351b6b 2294 sha_string(&ssh->exhashbase, s->vstring,
a7d4653a 2295 strcspn(s->vstring, "\015\012"));
d38d6a1f 2296
2297 /*
2298 * Initialise SSHv2 protocol.
2299 */
2300 ssh->protocol = ssh2_protocol;
2301 ssh2_protocol_setup(ssh);
2302 ssh->s_rdpkt = ssh2_rdpkt;
2303 } else {
2304 /*
2305 * Initialise SSHv1 protocol.
2306 */
2307 ssh->protocol = ssh1_protocol;
2308 ssh1_protocol_setup(ssh);
2309 ssh->s_rdpkt = ssh1_rdpkt;
2310 }
2311 logeventf(ssh, "We claim version: %.*s",
a7d4653a 2312 strcspn(verstring, "\015\012"), verstring);
51470298 2313 sk_write(ssh->s, verstring, strlen(verstring));
d38d6a1f 2314 sfree(verstring);
e5574168 2315 }
d38d6a1f 2316
2317 logeventf(ssh, "Using SSH protocol version %d", ssh->version);
2318
125105d1 2319 update_specials_menu(ssh->frontend);
51470298 2320 ssh->state = SSH_STATE_BEFORE_SIZE;
39934deb 2321 ssh->pinger = pinger_new(&ssh->cfg, &ssh_backend, ssh);
8df7a775 2322
51470298 2323 sfree(s->vstring);
50526e47 2324
8df7a775 2325 crFinish(0);
2326}
2327
51470298 2328static void ssh_gotdata(Ssh ssh, unsigned char *data, int datalen)
8df7a775 2329{
51470298 2330 crBegin(ssh->ssh_gotdata_crstate);
8df7a775 2331
2332 /*
2333 * To begin with, feed the characters one by one to the
2334 * protocol initialisation / selection function do_ssh_init().
2335 * When that returns 0, we're done with the initial greeting
2336 * exchange and can move on to packet discipline.
2337 */
2338 while (1) {
51470298 2339 int ret; /* need not be kept across crReturn */
8df7a775 2340 if (datalen == 0)
2341 crReturnV; /* more data please */
51470298 2342 ret = do_ssh_init(ssh, *data);
32874aea 2343 data++;
2344 datalen--;
8df7a775 2345 if (ret == 0)
2346 break;
2347 }
2348
2349 /*
2350 * We emerge from that loop when the initial negotiation is
2351 * over and we have selected an s_rdpkt function. Now pass
2352 * everything to s_rdpkt, and then pass the resulting packets
2353 * to the proper protocol handler.
2354 */
2355 if (datalen == 0)
2356 crReturnV;
2357 while (1) {
2358 while (datalen > 0) {
ff3187f6 2359 struct Packet *pktin = ssh->s_rdpkt(ssh, &data, &datalen);
2360 if (pktin) {
2361 ssh->protocol(ssh, NULL, 0, pktin);
2362 ssh_free_packet(pktin);
8df7a775 2363 }
ff3187f6 2364 if (ssh->state == SSH_STATE_CLOSED)
2365 return;
8df7a775 2366 }
2367 crReturnV;
2368 }
2369 crFinishV;
2370}
2371
ac934965 2372static int ssh_do_close(Ssh ssh, int notify_exit)
32874aea 2373{
ac934965 2374 int i, ret = 0;
36f94d1f 2375 struct ssh_channel *c;
2376
51470298 2377 ssh->state = SSH_STATE_CLOSED;
2378 if (ssh->s) {
2379 sk_close(ssh->s);
2380 ssh->s = NULL;
ac934965 2381 if (notify_exit)
2382 notify_remote_exit(ssh->frontend);
2383 else
2384 ret = 1;
f3ab576e 2385 }
36f94d1f 2386 /*
2387 * Now we must shut down any port and X forwardings going
2388 * through this connection.
2389 */
74a98066 2390 if (ssh->channels) {
2391 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
2392 switch (c->type) {
2393 case CHAN_X11:
2394 x11_close(c->u.x11.s);
2395 break;
2396 case CHAN_SOCKDATA:
2397 pfd_close(c->u.pfd.s);
2398 break;
2399 }
2400 del234(ssh->channels, c);
2401 if (ssh->version == 2)
2402 bufchain_clear(&c->v.v2.outbuffer);
2403 sfree(c);
36f94d1f 2404 }
36f94d1f 2405 }
ac934965 2406
2407 return ret;
36f94d1f 2408}
2409
cbe2d68f 2410static int ssh_closing(Plug plug, const char *error_msg, int error_code,
36f94d1f 2411 int calling_back)
2412{
2413 Ssh ssh = (Ssh) plug;
ac934965 2414 int need_notify = ssh_do_close(ssh, FALSE);
2415
2416 if (!error_msg && !ssh->close_expected) {
2417 error_msg = "Server unexpectedly closed network connection";
2418 }
2419
7e78000d 2420 if (error_msg) {
32874aea 2421 /* A socket error has occurred. */
247308b5 2422 logevent(error_msg);
971bcc0a 2423 connection_fatal(ssh->frontend, "%s", error_msg);
7e78000d 2424 } else {
ac934965 2425 logevent("Server closed network connection");
8df7a775 2426 }
ac934965 2427 if (need_notify)
2428 notify_remote_exit(ssh->frontend);
7e78000d 2429 return 0;
2430}
2431
32874aea 2432static int ssh_receive(Plug plug, int urgent, char *data, int len)
2433{
51470298 2434 Ssh ssh = (Ssh) plug;
d8baa528 2435 ssh_gotdata(ssh, (unsigned char *)data, len);
51470298 2436 if (ssh->state == SSH_STATE_CLOSED) {
ac934965 2437 ssh_do_close(ssh, TRUE);
32874aea 2438 return 0;
3257deae 2439 }
fef97f43 2440 return 1;
374330e2 2441}
2442
5471d09a 2443static void ssh_sent(Plug plug, int bufsize)
2444{
51470298 2445 Ssh ssh = (Ssh) plug;
5471d09a 2446 /*
2447 * If the send backlog on the SSH socket itself clears, we
2448 * should unthrottle the whole world if it was throttled.
2449 */
2450 if (bufsize < SSH_MAX_BACKLOG)
51470298 2451 ssh_throttle_all(ssh, 0, bufsize);
5471d09a 2452}
2453
fb09bf1c 2454/*
8df7a775 2455 * Connect to specified host and port.
2456 * Returns an error message, or NULL on success.
6e1ebb76 2457 * Also places the canonical host name into `realhost'. It must be
2458 * freed by the caller.
8df7a775 2459 */
cbe2d68f 2460static const char *connect_to_host(Ssh ssh, char *host, int port,
79bf227b 2461 char **realhost, int nodelay, int keepalive)
8df7a775 2462{
51470298 2463 static const struct plug_function_table fn_table = {
7e78000d 2464 ssh_closing,
5471d09a 2465 ssh_receive,
2466 ssh_sent,
2467 NULL
51470298 2468 };
7e78000d 2469
8df7a775 2470 SockAddr addr;
cbe2d68f 2471 const char *err;
8df7a775 2472
3d88e64d 2473 ssh->savedhost = snewn(1 + strlen(host), char);
51470298 2474 if (!ssh->savedhost)
8df7a775 2475 fatalbox("Out of memory");
51470298 2476 strcpy(ssh->savedhost, host);
8df7a775 2477
2478 if (port < 0)
2479 port = 22; /* default ssh port */
51470298 2480 ssh->savedport = port;
8df7a775 2481
2482 /*
2483 * Try to find host.
2484 */
05581745 2485 logeventf(ssh, "Looking up host \"%s\"%s", host,
2486 (ssh->cfg.addressfamily == ADDRTYPE_IPV4 ? " (IPv4)" :
2487 (ssh->cfg.addressfamily == ADDRTYPE_IPV6 ? " (IPv6)" : "")));
2488 addr = name_lookup(host, port, realhost, &ssh->cfg,
2489 ssh->cfg.addressfamily);
170c1e6e 2490 if ((err = sk_addr_error(addr)) != NULL) {
2491 sk_addr_free(addr);
8df7a775 2492 return err;
170c1e6e 2493 }
8df7a775 2494
8df7a775 2495 /*
2496 * Open socket.
2497 */
3ad9d396 2498 {
57356d63 2499 char addrbuf[100];
3ad9d396 2500 sk_getaddr(addr, addrbuf, 100);
57356d63 2501 logeventf(ssh, "Connecting to %s port %d", addrbuf, port);
3ad9d396 2502 }
51470298 2503 ssh->fn = &fn_table;
e8fa8f62 2504 ssh->s = new_connection(addr, *realhost, port,
79bf227b 2505 0, 1, nodelay, keepalive, (Plug) ssh, &ssh->cfg);
70e5d0fd 2506 if ((err = sk_socket_error(ssh->s)) != NULL) {
51470298 2507 ssh->s = NULL;
39934deb 2508 notify_remote_exit(ssh->frontend);
8df7a775 2509 return err;
67c4ba2e 2510 }
8df7a775 2511
8df7a775 2512 return NULL;
2513}
2514
2515/*
5471d09a 2516 * Throttle or unthrottle the SSH connection.
2517 */
51470298 2518static void ssh1_throttle(Ssh ssh, int adjust)
5471d09a 2519{
51470298 2520 int old_count = ssh->v1_throttle_count;
2521 ssh->v1_throttle_count += adjust;
2522 assert(ssh->v1_throttle_count >= 0);
2523 if (ssh->v1_throttle_count && !old_count) {
2524 sk_set_frozen(ssh->s, 1);
2525 } else if (!ssh->v1_throttle_count && old_count) {
2526 sk_set_frozen(ssh->s, 0);
5471d09a 2527 }
2528}
2529
2530/*
2531 * Throttle or unthrottle _all_ local data streams (for when sends
2532 * on the SSH connection itself back up).
2533 */
51470298 2534static void ssh_throttle_all(Ssh ssh, int enable, int bufsize)
5471d09a 2535{
2536 int i;
2537 struct ssh_channel *c;
2538
51470298 2539 if (enable == ssh->throttled_all)
5471d09a 2540 return;
51470298 2541 ssh->throttled_all = enable;
2542 ssh->overall_bufsize = bufsize;
2543 if (!ssh->channels)
5471d09a 2544 return;
51470298 2545 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
5471d09a 2546 switch (c->type) {
2547 case CHAN_MAINSESSION:
2548 /*
2549 * This is treated separately, outside the switch.
2550 */
2551 break;
2552 case CHAN_X11:
2553 x11_override_throttle(c->u.x11.s, enable);
2554 break;
2555 case CHAN_AGENT:
2556 /* Agent channels require no buffer management. */
2557 break;
2558 case CHAN_SOCKDATA:
36f94d1f 2559 pfd_override_throttle(c->u.pfd.s, enable);
5471d09a 2560 break;
2561 }
2562 }
2563}
2564
2565/*
51470298 2566 * Username and password input, abstracted off into routines
2567 * reusable in several places - even between SSH1 and SSH2.
0405e71f 2568 */
0405e71f 2569
2570/* Set up a username or password input loop on a given buffer. */
ae9ae89f 2571static void setup_userpass_input(Ssh ssh, char *buffer, int buflen, int echo)
0405e71f 2572{
51470298 2573 ssh->userpass_input_buffer = buffer;
2574 ssh->userpass_input_buflen = buflen;
2575 ssh->userpass_input_bufpos = 0;
2576 ssh->userpass_input_echo = echo;
0405e71f 2577}
2578
2579/*
2580 * Process some terminal data in the course of username/password
2581 * input. Returns >0 for success (line of input returned in
2582 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2583 * for inconclusive (keep waiting for more input please).
2584 */
ae9ae89f 2585static int process_userpass_input(Ssh ssh, unsigned char *in, int inlen)
0405e71f 2586{
2587 char c;
2588
2589 while (inlen--) {
2590 switch (c = *in++) {
2591 case 10:
2592 case 13:
51470298 2593 ssh->userpass_input_buffer[ssh->userpass_input_bufpos] = 0;
2594 ssh->userpass_input_buffer[ssh->userpass_input_buflen-1] = 0;
0405e71f 2595 return +1;
2596 break;
2597 case 8:
2598 case 127:
51470298 2599 if (ssh->userpass_input_bufpos > 0) {
2600 if (ssh->userpass_input_echo)
2601 c_write_str(ssh, "\b \b");
2602 ssh->userpass_input_bufpos--;
0405e71f 2603 }
2604 break;
2605 case 21:
2606 case 27:
51470298 2607 while (ssh->userpass_input_bufpos > 0) {
2608 if (ssh->userpass_input_echo)
2609 c_write_str(ssh, "\b \b");
2610 ssh->userpass_input_bufpos--;
0405e71f 2611 }
2612 break;
2613 case 3:
2614 case 4:
2615 return -1;
2616 break;
2617 default:
4692a14a 2618 /*
2619 * This simplistic check for printability is disabled
2620 * when we're doing password input, because some people
2621 * have control characters in their passwords.o
2622 */
2623 if ((!ssh->userpass_input_echo ||
2624 (c >= ' ' && c <= '~') ||
0405e71f 2625 ((unsigned char) c >= 160))
51470298 2626 && ssh->userpass_input_bufpos < ssh->userpass_input_buflen-1) {
2627 ssh->userpass_input_buffer[ssh->userpass_input_bufpos++] = c;
2628 if (ssh->userpass_input_echo)
2629 c_write(ssh, &c, 1);
0405e71f 2630 }
2631 break;
2632 }
2633 }
2634 return 0;
2635}
2636
f11d78f2 2637static void ssh_agent_callback(void *sshv, void *reply, int replylen)
839f10db 2638{
2639 Ssh ssh = (Ssh) sshv;
2640
2641 ssh->agent_response = reply;
2642 ssh->agent_response_len = replylen;
2643
2644 if (ssh->version == 1)
ff3187f6 2645 do_ssh1_login(ssh, NULL, -1, NULL);
839f10db 2646 else
ff3187f6 2647 do_ssh2_authconn(ssh, NULL, -1, NULL);
839f10db 2648}
2649
f11d78f2 2650static void ssh_agentf_callback(void *cv, void *reply, int replylen)
839f10db 2651{
2652 struct ssh_channel *c = (struct ssh_channel *)cv;
2653 Ssh ssh = c->ssh;
2654 void *sentreply = reply;
2655
2656 if (!sentreply) {
2657 /* Fake SSH_AGENT_FAILURE. */
2658 sentreply = "\0\0\0\1\5";
2659 replylen = 5;
2660 }
2661 if (ssh->version == 2) {
2662 ssh2_add_channel_data(c, sentreply, replylen);
2663 ssh2_try_send(c);
2664 } else {
2665 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
2666 PKT_INT, c->remoteid,
9a10ecf4 2667 PKTT_DATA,
839f10db 2668 PKT_INT, replylen,
2669 PKT_DATA, sentreply, replylen,
9a10ecf4 2670 PKTT_OTHER,
839f10db 2671 PKT_END);
2672 }
2673 if (reply)
2674 sfree(reply);
2675}
2676
0405e71f 2677/*
fb09bf1c 2678 * Handle the key exchange and user authentication phases.
2679 */
ff3187f6 2680static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen,
2681 struct Packet *pktin)
fb09bf1c 2682{
0016d70b 2683 int i, j, ret;
2684 unsigned char cookie[8], *ptr;
374330e2 2685 struct RSAKey servkey, hostkey;
2686 struct MD5Context md5c;
51470298 2687 struct do_ssh1_login_state {
2688 int len;
2689 unsigned char *rsabuf, *keystr1, *keystr2;
2690 unsigned long supported_ciphers_mask, supported_auths_mask;
2691 int tried_publickey, tried_agent;
2692 int tis_auth_refused, ccard_auth_refused;
2693 unsigned char session_id[16];
2694 int cipher_type;
2695 char username[100];
2696 void *publickey_blob;
2697 int publickey_bloblen;
2698 char password[100];
2699 char prompt[200];
2700 int pos;
2701 char c;
2702 int pwpkt_type;
2703 unsigned char request[5], *response, *p;
2704 int responselen;
2705 int keyi, nkeys;
2706 int authed;
2707 struct RSAKey key;
2708 Bignum challenge;
2709 char *commentp;
2710 int commentlen;
2711 };
2712 crState(do_ssh1_login_state);
2713
2714 crBegin(ssh->do_ssh1_login_crstate);
374330e2 2715
ff3187f6 2716 if (!pktin)
2717 crWaitUntil(pktin);
374330e2 2718
ff3187f6 2719 if (pktin->type != SSH1_SMSG_PUBLIC_KEY) {
6b5cf8b4 2720 bombout(("Public key packet not received"));
7ffdbc1a 2721 crStop(0);
8d5de777 2722 }
374330e2 2723
c5e9c988 2724 logevent("Received public keys");
374330e2 2725
ff3187f6 2726 ptr = ssh_pkt_getdata(pktin, 8);
0016d70b 2727 if (!ptr) {
2728 bombout(("SSH1 public key packet stopped before random cookie"));
2729 crStop(0);
2730 }
2731 memcpy(cookie, ptr, 8);
374330e2 2732
ff3187f6 2733 if (!ssh1_pkt_getrsakey(pktin, &servkey, &s->keystr1) ||
2734 !ssh1_pkt_getrsakey(pktin, &hostkey, &s->keystr2)) {
ae0500e5 2735 bombout(("Failed to read SSH1 public keys from public key packet"));
0016d70b 2736 crStop(0);
2737 }
374330e2 2738
c5e9c988 2739 /*
1c2a93c4 2740 * Log the host key fingerprint.
c5e9c988 2741 */
c5e9c988 2742 {
2743 char logmsg[80];
1c2a93c4 2744 logevent("Host key fingerprint is:");
c5e9c988 2745 strcpy(logmsg, " ");
32874aea 2746 hostkey.comment = NULL;
2747 rsa_fingerprint(logmsg + strlen(logmsg),
2748 sizeof(logmsg) - strlen(logmsg), &hostkey);
c5e9c988 2749 logevent(logmsg);
2750 }
2751
ff3187f6 2752 ssh->v1_remote_protoflags = ssh_pkt_getuint32(pktin);
2753 s->supported_ciphers_mask = ssh_pkt_getuint32(pktin);
2754 s->supported_auths_mask = ssh_pkt_getuint32(pktin);
bea1ef5f 2755
51470298 2756 ssh->v1_local_protoflags =
2757 ssh->v1_remote_protoflags & SSH1_PROTOFLAGS_SUPPORTED;
2758 ssh->v1_local_protoflags |= SSH1_PROTOFLAG_SCREEN_NUMBER;
b96dc54c 2759
c5e9c988 2760 MD5Init(&md5c);
51470298 2761 MD5Update(&md5c, s->keystr2, hostkey.bytes);
2762 MD5Update(&md5c, s->keystr1, servkey.bytes);
0016d70b 2763 MD5Update(&md5c, cookie, 8);
51470298 2764 MD5Final(s->session_id, &md5c);
374330e2 2765
32874aea 2766 for (i = 0; i < 32; i++)
51470298 2767 ssh->session_key[i] = random_byte();
374330e2 2768
0016d70b 2769 /*
2770 * Verify that the `bits' and `bytes' parameters match.
2771 */
2772 if (hostkey.bits > hostkey.bytes * 8 ||
2773 servkey.bits > servkey.bytes * 8) {
2774 bombout(("SSH1 public keys were badly formatted"));
2775 crStop(0);
2776 }
2777
51470298 2778 s->len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
374330e2 2779
3d88e64d 2780 s->rsabuf = snewn(s->len, unsigned char);
51470298 2781 if (!s->rsabuf)
374330e2 2782 fatalbox("Out of memory");
2783
89ee5268 2784 /*
2785 * Verify the host key.
2786 */
2787 {
32874aea 2788 /*
2789 * First format the key into a string.
2790 */
2791 int len = rsastr_len(&hostkey);
2792 char fingerprint[100];
3d88e64d 2793 char *keystr = snewn(len, char);
32874aea 2794 if (!keystr)
2795 fatalbox("Out of memory");
2796 rsastr_fmt(keystr, &hostkey);
2797 rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
a8327734 2798 verify_ssh_host_key(ssh->frontend,
2799 ssh->savedhost, ssh->savedport, "rsa", keystr,
32874aea 2800 fingerprint);
2801 sfree(keystr);
2802 }
2803
2804 for (i = 0; i < 32; i++) {
51470298 2805 s->rsabuf[i] = ssh->session_key[i];
374330e2 2806 if (i < 16)
51470298 2807 s->rsabuf[i] ^= s->session_id[i];
374330e2 2808 }
2809
2810 if (hostkey.bytes > servkey.bytes) {
0016d70b 2811 ret = rsaencrypt(s->rsabuf, 32, &servkey);
2812 if (ret)
2813 ret = rsaencrypt(s->rsabuf, servkey.bytes, &hostkey);
374330e2 2814 } else {
0016d70b 2815 ret = rsaencrypt(s->rsabuf, 32, &hostkey);
2816 if (ret)
2817 ret = rsaencrypt(s->rsabuf, hostkey.bytes, &servkey);
2818 }
2819 if (!ret) {
2820 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2821 crStop(0);
374330e2 2822 }
2823
c5e9c988 2824 logevent("Encrypted session key");
2825
ca20bfcf 2826 {
2827 int cipher_chosen = 0, warn = 0;
2828 char *cipher_string = NULL;
51470298 2829 int i;
ca20bfcf 2830 for (i = 0; !cipher_chosen && i < CIPHER_MAX; i++) {
86916870 2831 int next_cipher = ssh->cfg.ssh_cipherlist[i];
ca20bfcf 2832 if (next_cipher == CIPHER_WARN) {
2833 /* If/when we choose a cipher, warn about it */
2834 warn = 1;
2835 } else if (next_cipher == CIPHER_AES) {
2836 /* XXX Probably don't need to mention this. */
2837 logevent("AES not supported in SSH1, skipping");
2838 } else {
2839 switch (next_cipher) {
51470298 2840 case CIPHER_3DES: s->cipher_type = SSH_CIPHER_3DES;
ca20bfcf 2841 cipher_string = "3DES"; break;
51470298 2842 case CIPHER_BLOWFISH: s->cipher_type = SSH_CIPHER_BLOWFISH;
ca20bfcf 2843 cipher_string = "Blowfish"; break;
51470298 2844 case CIPHER_DES: s->cipher_type = SSH_CIPHER_DES;
ca20bfcf 2845 cipher_string = "single-DES"; break;
2846 }
51470298 2847 if (s->supported_ciphers_mask & (1 << s->cipher_type))
ca20bfcf 2848 cipher_chosen = 1;
2849 }
2850 }
2851 if (!cipher_chosen) {
51470298 2852 if ((s->supported_ciphers_mask & (1 << SSH_CIPHER_3DES)) == 0)
6b5cf8b4 2853 bombout(("Server violates SSH 1 protocol by not "
ca20bfcf 2854 "supporting 3DES encryption"));
2855 else
2856 /* shouldn't happen */
6b5cf8b4 2857 bombout(("No supported ciphers found"));
7ffdbc1a 2858 crStop(0);
a99a05c0 2859 }
ca20bfcf 2860
2861 /* Warn about chosen cipher if necessary. */
bb348ab1 2862 if (warn) {
2863 sk_set_frozen(ssh->s, 1);
83e7d008 2864 askalg(ssh->frontend, "cipher", cipher_string);
bb348ab1 2865 sk_set_frozen(ssh->s, 0);
2866 }
bea1ef5f 2867 }
ca20bfcf 2868
51470298 2869 switch (s->cipher_type) {
32874aea 2870 case SSH_CIPHER_3DES:
2871 logevent("Using 3DES encryption");
2872 break;
2873 case SSH_CIPHER_DES:
2874 logevent("Using single-DES encryption");
2875 break;
2876 case SSH_CIPHER_BLOWFISH:
2877 logevent("Using Blowfish encryption");
2878 break;
c5e9c988 2879 }
bea1ef5f 2880
51470298 2881 send_packet(ssh, SSH1_CMSG_SESSION_KEY,
2882 PKT_CHAR, s->cipher_type,
32874aea 2883 PKT_DATA, cookie, 8,
51470298 2884 PKT_CHAR, (s->len * 8) >> 8, PKT_CHAR, (s->len * 8) & 0xFF,
2885 PKT_DATA, s->rsabuf, s->len,
2886 PKT_INT, ssh->v1_local_protoflags, PKT_END);
fb09bf1c 2887
c5e9c988 2888 logevent("Trying to enable encryption...");
374330e2 2889
51470298 2890 sfree(s->rsabuf);
374330e2 2891
51470298 2892 ssh->cipher = (s->cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
2893 s->cipher_type == SSH_CIPHER_DES ? &ssh_des :
2894 &ssh_3des);
371e569c 2895 ssh->v1_cipher_ctx = ssh->cipher->make_context();
2896 ssh->cipher->sesskey(ssh->v1_cipher_ctx, ssh->session_key);
57356d63 2897 logeventf(ssh, "Initialised %s encryption", ssh->cipher->text_name);
374330e2 2898
0183b242 2899 ssh->crcda_ctx = crcda_make_context();
2900 logevent("Installing CRC compensation attack detector");
2901
679539d7 2902 if (servkey.modulus) {
2903 sfree(servkey.modulus);
2904 servkey.modulus = NULL;
2905 }
2906 if (servkey.exponent) {
2907 sfree(servkey.exponent);
2908 servkey.exponent = NULL;
2909 }
2910 if (hostkey.modulus) {
2911 sfree(hostkey.modulus);
2912 hostkey.modulus = NULL;
2913 }
2914 if (hostkey.exponent) {
2915 sfree(hostkey.exponent);
2916 hostkey.exponent = NULL;
2917 }
ff3187f6 2918 crWaitUntil(pktin);
374330e2 2919
ff3187f6 2920 if (pktin->type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 2921 bombout(("Encryption not successfully enabled"));
7ffdbc1a 2922 crStop(0);
8d5de777 2923 }
374330e2 2924
c5e9c988 2925 logevent("Successfully started encryption");
2926
374330e2 2927 fflush(stdout);
2928 {
aa09f7d0 2929 if (!*ssh->cfg.username) {
c0a81592 2930 if (ssh_get_line && !ssh_getline_pw_only) {
32874aea 2931 if (!ssh_get_line("login as: ",
51470298 2932 s->username, sizeof(s->username), FALSE)) {
32874aea 2933 /*
2934 * get_line failed to get a username.
2935 * Terminate.
2936 */
2937 logevent("No username provided. Abandoning session.");
ac934965 2938 ssh->close_expected = TRUE;
3bb2f322 2939 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 2940 crStop(1);
32874aea 2941 }
2942 } else {
51470298 2943 int ret; /* need not be kept over crReturn */
2944 c_write_str(ssh, "login as: ");
2945 ssh->send_ok = 1;
0405e71f 2946
51470298 2947 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
0405e71f 2948 do {
ff3187f6 2949 crWaitUntil(!pktin);
51470298 2950 ret = process_userpass_input(ssh, in, inlen);
0405e71f 2951 } while (ret == 0);
2952 if (ret < 0)
2953 cleanup_exit(0);
51470298 2954 c_write_str(ssh, "\r\n");
32874aea 2955 }
2956 } else {
86916870 2957 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
51470298 2958 s->username[sizeof(s->username)-1] = '\0';
374330e2 2959 }
fb09bf1c 2960
51470298 2961 send_packet(ssh, SSH1_CMSG_USER, PKT_STR, s->username, PKT_END);
c5e9c988 2962 {
51470298 2963 char userlog[22 + sizeof(s->username)];
2964 sprintf(userlog, "Sent username \"%s\"", s->username);
c5e9c988 2965 logevent(userlog);
32874aea 2966 if (flags & FLAG_INTERACTIVE &&
2967 (!((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)))) {
3c8e959b 2968 strcat(userlog, "\r\n");
51470298 2969 c_write_str(ssh, userlog);
3c8e959b 2970 }
c5e9c988 2971 }
374330e2 2972 }
2973
ff3187f6 2974 crWaitUntil(pktin);
374330e2 2975
51470298 2976 if ((ssh->remote_bugs & BUG_CHOKES_ON_RSA)) {
0df73905 2977 /* We must not attempt PK auth. Pretend we've already tried it. */
51470298 2978 s->tried_publickey = s->tried_agent = 1;
0df73905 2979 } else {
51470298 2980 s->tried_publickey = s->tried_agent = 0;
0df73905 2981 }
51470298 2982 s->tis_auth_refused = s->ccard_auth_refused = 0;
86916870 2983 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
9a30e26b 2984 if (!filename_is_null(ssh->cfg.keyfile)) {
2985 if (!rsakey_pubblob(&ssh->cfg.keyfile,
222d54dc 2986 &s->publickey_blob, &s->publickey_bloblen, NULL))
51470298 2987 s->publickey_blob = NULL;
396778f1 2988 } else
51470298 2989 s->publickey_blob = NULL;
7cca0d81 2990
ff3187f6 2991 while (pktin->type == SSH1_SMSG_FAILURE) {
51470298 2992 s->pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
614a20a0 2993
51470298 2994 if (agent_exists() && !s->tried_agent) {
32874aea 2995 /*
2996 * Attempt RSA authentication using Pageant.
2997 */
32874aea 2998 void *r;
2999
51470298 3000 s->authed = FALSE;
3001 s->tried_agent = 1;
32874aea 3002 logevent("Pageant is running. Requesting keys.");
3003
3004 /* Request the keys held by the agent. */
51470298 3005 PUT_32BIT(s->request, 1);
3006 s->request[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES;
839f10db 3007 if (!agent_query(s->request, 5, &r, &s->responselen,
3008 ssh_agent_callback, ssh)) {
3009 do {
3010 crReturn(0);
ff3187f6 3011 if (pktin) {
839f10db 3012 bombout(("Unexpected data from server while waiting"
3013 " for agent response"));
3014 crStop(0);
3015 }
ff3187f6 3016 } while (pktin || inlen > 0);
839f10db 3017 r = ssh->agent_response;
3018 s->responselen = ssh->agent_response_len;
3019 }
51470298 3020 s->response = (unsigned char *) r;
3021 if (s->response && s->responselen >= 5 &&
3022 s->response[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER) {
3023 s->p = s->response + 5;
3024 s->nkeys = GET_32BIT(s->p);
3025 s->p += 4;
32874aea 3026 {
3027 char buf[64];
51470298 3028 sprintf(buf, "Pageant has %d SSH1 keys", s->nkeys);
32874aea 3029 logevent(buf);
3030 }
51470298 3031 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
32874aea 3032 {
3033 char buf[64];
51470298 3034 sprintf(buf, "Trying Pageant key #%d", s->keyi);
32874aea 3035 logevent(buf);
3036 }
51470298 3037 if (s->publickey_blob &&
3038 !memcmp(s->p, s->publickey_blob,
3039 s->publickey_bloblen)) {
396778f1 3040 logevent("This key matches configured key file");
51470298 3041 s->tried_publickey = 1;
396778f1 3042 }
51470298 3043 s->p += 4;
0016d70b 3044 {
3045 int n, ok = FALSE;
3046 do { /* do while (0) to make breaking easy */
3047 n = ssh1_read_bignum
3048 (s->p, s->responselen-(s->p-s->response),
3049 &s->key.exponent);
3050 if (n < 0)
3051 break;
3052 s->p += n;
3053 n = ssh1_read_bignum
3054 (s->p, s->responselen-(s->p-s->response),
3055 &s->key.modulus);
3056 if (n < 0)
3057 break;
3058 s->p += n;
3059 if (s->responselen - (s->p-s->response) < 4)
3060 break;
3061 s->commentlen = GET_32BIT(s->p);
3062 s->p += 4;
3063 if (s->responselen - (s->p-s->response) <
3064 s->commentlen)
3065 break;
3066 s->commentp = (char *)s->p;
3067 s->p += s->commentlen;
3068 ok = TRUE;
3069 } while (0);
3070 if (!ok) {
3071 logevent("Pageant key list packet was truncated");
3072 break;
3073 }
3074 }
51470298 3075 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
3076 PKT_BIGNUM, s->key.modulus, PKT_END);
ff3187f6 3077 crWaitUntil(pktin);
3078 if (pktin->type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
32874aea 3079 logevent("Key refused");
3080 continue;
3081 }
3082 logevent("Received RSA challenge");
ff3187f6 3083 if ((s->challenge = ssh1_pkt_getmp(pktin)) == NULL) {
0016d70b 3084 bombout(("Server's RSA challenge was badly formatted"));
3085 crStop(0);
3086 }
3087
32874aea 3088 {
3089 char *agentreq, *q, *ret;
2d466ffd 3090 void *vret;
32874aea 3091 int len, retlen;
3092 len = 1 + 4; /* message type, bit count */
51470298 3093 len += ssh1_bignum_length(s->key.exponent);
3094 len += ssh1_bignum_length(s->key.modulus);
3095 len += ssh1_bignum_length(s->challenge);
32874aea 3096 len += 16; /* session id */
3097 len += 4; /* response format */
3d88e64d 3098 agentreq = snewn(4 + len, char);
32874aea 3099 PUT_32BIT(agentreq, len);
3100 q = agentreq + 4;
3101 *q++ = SSH1_AGENTC_RSA_CHALLENGE;
51470298 3102 PUT_32BIT(q, bignum_bitcount(s->key.modulus));
32874aea 3103 q += 4;
51470298 3104 q += ssh1_write_bignum(q, s->key.exponent);
3105 q += ssh1_write_bignum(q, s->key.modulus);
3106 q += ssh1_write_bignum(q, s->challenge);
3107 memcpy(q, s->session_id, 16);
32874aea 3108 q += 16;
3109 PUT_32BIT(q, 1); /* response format */
839f10db 3110 if (!agent_query(agentreq, len + 4, &vret, &retlen,
3111 ssh_agent_callback, ssh)) {
3112 sfree(agentreq);
3113 do {
3114 crReturn(0);
ff3187f6 3115 if (pktin) {
839f10db 3116 bombout(("Unexpected data from server"
3117 " while waiting for agent"
3118 " response"));
3119 crStop(0);
3120 }
ff3187f6 3121 } while (pktin || inlen > 0);
839f10db 3122 vret = ssh->agent_response;
3123 retlen = ssh->agent_response_len;
3124 } else
3125 sfree(agentreq);
2d466ffd 3126 ret = vret;
32874aea 3127 if (ret) {
3128 if (ret[4] == SSH1_AGENT_RSA_RESPONSE) {
3129 logevent("Sending Pageant's response");
51470298 3130 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
32874aea 3131 PKT_DATA, ret + 5, 16,
3132 PKT_END);
3133 sfree(ret);
ff3187f6 3134 crWaitUntil(pktin);
3135 if (pktin->type == SSH1_SMSG_SUCCESS) {
32874aea 3136 logevent
3137 ("Pageant's response accepted");
3138 if (flags & FLAG_VERBOSE) {
51470298 3139 c_write_str(ssh, "Authenticated using"
3140 " RSA key \"");
3141 c_write(ssh, s->commentp,
3142 s->commentlen);
3143 c_write_str(ssh, "\" from agent\r\n");
32874aea 3144 }
51470298 3145 s->authed = TRUE;
32874aea 3146 } else
3147 logevent
3148 ("Pageant's response not accepted");
3149 } else {
3150 logevent
3151 ("Pageant failed to answer challenge");
3152 sfree(ret);
3153 }
3154 } else {
3155 logevent("No reply received from Pageant");
3156 }
3157 }
51470298 3158 freebn(s->key.exponent);
3159 freebn(s->key.modulus);
3160 freebn(s->challenge);
3161 if (s->authed)
32874aea 3162 break;
3163 }
29b1d0b3 3164 sfree(s->response);
32874aea 3165 }
51470298 3166 if (s->authed)
32874aea 3167 break;
3168 }
9a30e26b 3169 if (!filename_is_null(ssh->cfg.keyfile) && !s->tried_publickey)
51470298 3170 s->pwpkt_type = SSH1_CMSG_AUTH_RSA;
32874aea 3171
86916870 3172 if (ssh->cfg.try_tis_auth &&
51470298 3173 (s->supported_auths_mask & (1 << SSH1_AUTH_TIS)) &&
3174 !s->tis_auth_refused) {
3175 s->pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
32874aea 3176 logevent("Requested TIS authentication");
51470298 3177 send_packet(ssh, SSH1_CMSG_AUTH_TIS, PKT_END);
ff3187f6 3178 crWaitUntil(pktin);
3179 if (pktin->type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
32874aea 3180 logevent("TIS authentication declined");
3181 if (flags & FLAG_INTERACTIVE)
51470298 3182 c_write_str(ssh, "TIS authentication refused.\r\n");
3183 s->tis_auth_refused = 1;
614a20a0 3184 continue;
32874aea 3185 } else {
0016d70b 3186 char *challenge;
3187 int challengelen;
3188
ff3187f6 3189 ssh_pkt_getstring(pktin, &challenge, &challengelen);
0016d70b 3190 if (!challenge) {
3191 bombout(("TIS challenge packet was badly formed"));
3192 crStop(0);
3193 }
32874aea 3194 logevent("Received TIS challenge");
51470298 3195 if (challengelen > sizeof(s->prompt) - 1)
3196 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
0016d70b 3197 memcpy(s->prompt, challenge, challengelen);
614a20a0 3198 /* Prompt heuristic comes from OpenSSH */
51470298 3199 strncpy(s->prompt + challengelen,
3200 memchr(s->prompt, '\n', challengelen) ?
614a20a0 3201 "": "\r\nResponse: ",
51470298 3202 (sizeof s->prompt) - challengelen);
3203 s->prompt[(sizeof s->prompt) - 1] = '\0';
32874aea 3204 }
3205 }
86916870 3206 if (ssh->cfg.try_tis_auth &&
51470298 3207 (s->supported_auths_mask & (1 << SSH1_AUTH_CCARD)) &&
3208 !s->ccard_auth_refused) {
3209 s->pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
32874aea 3210 logevent("Requested CryptoCard authentication");
51470298 3211 send_packet(ssh, SSH1_CMSG_AUTH_CCARD, PKT_END);
ff3187f6 3212 crWaitUntil(pktin);
3213 if (pktin->type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
32874aea 3214 logevent("CryptoCard authentication declined");
51470298 3215 c_write_str(ssh, "CryptoCard authentication refused.\r\n");
3216 s->ccard_auth_refused = 1;
614a20a0 3217 continue;
32874aea 3218 } else {
0016d70b 3219 char *challenge;
3220 int challengelen;
3221
ff3187f6 3222 ssh_pkt_getstring(pktin, &challenge, &challengelen);
0016d70b 3223 if (!challenge) {
3224 bombout(("CryptoCard challenge packet was badly formed"));
3225 crStop(0);
3226 }
32874aea 3227 logevent("Received CryptoCard challenge");
51470298 3228 if (challengelen > sizeof(s->prompt) - 1)
3229 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
0016d70b 3230 memcpy(s->prompt, challenge, challengelen);
51470298 3231 strncpy(s->prompt + challengelen,
3232 memchr(s->prompt, '\n', challengelen) ?
614a20a0 3233 "" : "\r\nResponse: ",
51470298 3234 sizeof(s->prompt) - challengelen);
3235 s->prompt[sizeof(s->prompt) - 1] = '\0';
32874aea 3236 }
3237 }
51470298 3238 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
3239 sprintf(s->prompt, "%.90s@%.90s's password: ",
3240 s->username, ssh->savedhost);
32874aea 3241 }
51470298 3242 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
32874aea 3243 char *comment = NULL;
231ee168 3244 int type;
3245 char msgbuf[256];
32874aea 3246 if (flags & FLAG_VERBOSE)
51470298 3247 c_write_str(ssh, "Trying public key authentication.\r\n");
6c6d9ed9 3248 logeventf(ssh, "Trying public key \"%s\"",
3249 filename_to_str(&ssh->cfg.keyfile));
9a30e26b 3250 type = key_type(&ssh->cfg.keyfile);
231ee168 3251 if (type != SSH_KEYTYPE_SSH1) {
3252 sprintf(msgbuf, "Key is of wrong type (%s)",
3253 key_type_to_str(type));
3254 logevent(msgbuf);
51470298 3255 c_write_str(ssh, msgbuf);
3256 c_write_str(ssh, "\r\n");
3257 s->tried_publickey = 1;
231ee168 3258 continue;
3259 }
9a30e26b 3260 if (!rsakey_encrypted(&ssh->cfg.keyfile, &comment)) {
32874aea 3261 if (flags & FLAG_VERBOSE)
51470298 3262 c_write_str(ssh, "No passphrase required.\r\n");
32874aea 3263 goto tryauth;
3264 }
51470298 3265 sprintf(s->prompt, "Passphrase for key \"%.100s\": ", comment);
32874aea 3266 sfree(comment);
3267 }
a52f067e 3268
614a20a0 3269 /*
3270 * Show password prompt, having first obtained it via a TIS
3271 * or CryptoCard exchange if we're doing TIS or CryptoCard
3272 * authentication.
3273 */
fa17a66e 3274 if (ssh_get_line) {
51470298 3275 if (!ssh_get_line(s->prompt, s->password,
3276 sizeof(s->password), TRUE)) {
32874aea 3277 /*
3278 * get_line failed to get a password (for example
3279 * because one was supplied on the command line
3280 * which has already failed to work). Terminate.
3281 */
51470298 3282 send_packet(ssh, SSH1_MSG_DISCONNECT,
2bc6a386 3283 PKT_STR, "No more passwords available to try",
3284 PKT_END);
247308b5 3285 logevent("Unable to authenticate");
a8327734 3286 connection_fatal(ssh->frontend, "Unable to authenticate");
ac934965 3287 ssh->close_expected = TRUE;
3bb2f322 3288 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 3289 crStop(1);
32874aea 3290 }
fb09bf1c 3291 } else {
614a20a0 3292 /* Prompt may have come from server. We've munged it a bit, so
3293 * we know it to be zero-terminated at least once. */
51470298 3294 int ret; /* need not be saved over crReturn */
3295 c_write_untrusted(ssh, s->prompt, strlen(s->prompt));
3296 s->pos = 0;
0405e71f 3297
51470298 3298 setup_userpass_input(ssh, s->password, sizeof(s->password), 0);
0405e71f 3299 do {
ff3187f6 3300 crWaitUntil(!pktin);
51470298 3301 ret = process_userpass_input(ssh, in, inlen);
0405e71f 3302 } while (ret == 0);
3303 if (ret < 0)
3304 cleanup_exit(0);
51470298 3305 c_write_str(ssh, "\r\n");
32874aea 3306 }
3307
3308 tryauth:
51470298 3309 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
32874aea 3310 /*
3311 * Try public key authentication with the specified
3312 * key file.
3313 */
51470298 3314 s->tried_publickey = 1;
3315
3316 {
222d54dc 3317 const char *error = NULL;
3318 int ret = loadrsakey(&ssh->cfg.keyfile, &s->key, s->password,
3319 &error);
51470298 3320 if (ret == 0) {
3321 c_write_str(ssh, "Couldn't load private key from ");
9fab77dc 3322 c_write_str(ssh, filename_to_str(&ssh->cfg.keyfile));
222d54dc 3323 c_write_str(ssh, " (");
3324 c_write_str(ssh, error);
3325 c_write_str(ssh, ").\r\n");
51470298 3326 continue; /* go and try password */
3327 }
3328 if (ret == -1) {
3329 c_write_str(ssh, "Wrong passphrase.\r\n");
3330 s->tried_publickey = 0;
3331 continue; /* try again */
3332 }
32874aea 3333 }
3334
3335 /*
3336 * Send a public key attempt.
3337 */
51470298 3338 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
3339 PKT_BIGNUM, s->key.modulus, PKT_END);
32874aea 3340
ff3187f6 3341 crWaitUntil(pktin);
3342 if (pktin->type == SSH1_SMSG_FAILURE) {
51470298 3343 c_write_str(ssh, "Server refused our public key.\r\n");
32874aea 3344 continue; /* go and try password */
3345 }
ff3187f6 3346 if (pktin->type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
6b5cf8b4 3347 bombout(("Bizarre response to offer of public key"));
7ffdbc1a 3348 crStop(0);
32874aea 3349 }
32874aea 3350
51470298 3351 {
3352 int i;
3353 unsigned char buffer[32];
3354 Bignum challenge, response;
3355
ff3187f6 3356 if ((challenge = ssh1_pkt_getmp(pktin)) == NULL) {
0016d70b 3357 bombout(("Server's RSA challenge was badly formatted"));
3358 crStop(0);
3359 }
51470298 3360 response = rsadecrypt(challenge, &s->key);
3361 freebn(s->key.private_exponent);/* burn the evidence */
32874aea 3362
51470298 3363 for (i = 0; i < 32; i++) {
3364 buffer[i] = bignum_byte(response, 31 - i);
3365 }
3366
3367 MD5Init(&md5c);
3368 MD5Update(&md5c, buffer, 32);
3369 MD5Update(&md5c, s->session_id, 16);
3370 MD5Final(buffer, &md5c);
32874aea 3371
51470298 3372 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
3373 PKT_DATA, buffer, 16, PKT_END);
3374
3375 freebn(challenge);
3376 freebn(response);
3377 }
32874aea 3378
ff3187f6 3379 crWaitUntil(pktin);
3380 if (pktin->type == SSH1_SMSG_FAILURE) {
32874aea 3381 if (flags & FLAG_VERBOSE)
51470298 3382 c_write_str(ssh, "Failed to authenticate with"
3383 " our public key.\r\n");
32874aea 3384 continue; /* go and try password */
ff3187f6 3385 } else if (pktin->type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 3386 bombout(("Bizarre response to RSA authentication response"));
7ffdbc1a 3387 crStop(0);
32874aea 3388 }
3389
3390 break; /* we're through! */
3391 } else {
51470298 3392 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
32874aea 3393 /*
3394 * Defence against traffic analysis: we send a
3395 * whole bunch of packets containing strings of
3396 * different lengths. One of these strings is the
3397 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3398 * The others are all random data in
3399 * SSH1_MSG_IGNORE packets. This way a passive
3400 * listener can't tell which is the password, and
3401 * hence can't deduce the password length.
3402 *
3403 * Anybody with a password length greater than 16
3404 * bytes is going to have enough entropy in their
3405 * password that a listener won't find it _that_
3406 * much help to know how long it is. So what we'll
3407 * do is:
3408 *
3409 * - if password length < 16, we send 15 packets
3410 * containing string lengths 1 through 15
3411 *
3412 * - otherwise, we let N be the nearest multiple
3413 * of 8 below the password length, and send 8
3414 * packets containing string lengths N through
3415 * N+7. This won't obscure the order of
3416 * magnitude of the password length, but it will
3417 * introduce a bit of extra uncertainty.
3418 *
3419 * A few servers (the old 1.2.18 through 1.2.22)
3420 * can't deal with SSH1_MSG_IGNORE. For these
3421 * servers, we need an alternative defence. We make
3422 * use of the fact that the password is interpreted
3423 * as a C string: so we can append a NUL, then some
3424 * random data.
bd358db1 3425 *
3426 * One server (a Cisco one) can deal with neither
3427 * SSH1_MSG_IGNORE _nor_ a padded password string.
3428 * For this server we are left with no defences
3429 * against password length sniffing.
32874aea 3430 */
51470298 3431 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE)) {
b17c8428 3432 /*
3433 * The server can deal with SSH1_MSG_IGNORE, so
3434 * we can use the primary defence.
3435 */
32874aea 3436 int bottom, top, pwlen, i;
3437 char *randomstr;
3438
51470298 3439 pwlen = strlen(s->password);
32874aea 3440 if (pwlen < 16) {
3441 bottom = 0; /* zero length passwords are OK! :-) */
3442 top = 15;
3443 } else {
3444 bottom = pwlen & ~7;
3445 top = bottom + 7;
3446 }
3447
3448 assert(pwlen >= bottom && pwlen <= top);
3449
3d88e64d 3450 randomstr = snewn(top + 1, char);
32874aea 3451
3452 for (i = bottom; i <= top; i++) {
9a10ecf4 3453 if (i == pwlen) {
51470298 3454 defer_packet(ssh, s->pwpkt_type,
9a10ecf4 3455 PKTT_PASSWORD, PKT_STR, s->password,
3456 PKTT_OTHER, PKT_END);
3457 } else {
32874aea 3458 for (j = 0; j < i; j++) {
3459 do {
3460 randomstr[j] = random_byte();
3461 } while (randomstr[j] == '\0');
3462 }
3463 randomstr[i] = '\0';
51470298 3464 defer_packet(ssh, SSH1_MSG_IGNORE,
32874aea 3465 PKT_STR, randomstr, PKT_END);
3466 }
3467 }
bd358db1 3468 logevent("Sending password with camouflage packets");
51470298 3469 ssh_pkt_defersend(ssh);
679539d7 3470 sfree(randomstr);
bd358db1 3471 }
51470298 3472 else if (!(ssh->remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
b17c8428 3473 /*
3474 * The server can't deal with SSH1_MSG_IGNORE
3475 * but can deal with padded passwords, so we
3476 * can use the secondary defence.
3477 */
bd358db1 3478 char string[64];
51470298 3479 char *ss;
bd358db1 3480 int len;
3481
51470298 3482 len = strlen(s->password);
bd358db1 3483 if (len < sizeof(string)) {
51470298 3484 ss = string;
3485 strcpy(string, s->password);
bd358db1 3486 len++; /* cover the zero byte */
3487 while (len < sizeof(string)) {
3488 string[len++] = (char) random_byte();
3489 }
3490 } else {
51470298 3491 ss = s->password;
bd358db1 3492 }
3493 logevent("Sending length-padded password");
9a10ecf4 3494 send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
3495 PKT_INT, len, PKT_DATA, ss, len,
3496 PKTT_OTHER, PKT_END);
bd358db1 3497 } else {
3498 /*
3499 * The server has _both_
3500 * BUG_CHOKES_ON_SSH1_IGNORE and
3501 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3502 * therefore nothing we can do.
3503 */
3504 int len;
51470298 3505 len = strlen(s->password);
bd358db1 3506 logevent("Sending unpadded password");
9a10ecf4 3507 send_packet(ssh, s->pwpkt_type,
3508 PKTT_PASSWORD, PKT_INT, len,
3509 PKT_DATA, s->password, len,
3510 PKTT_OTHER, PKT_END);
32874aea 3511 }
3512 } else {
9a10ecf4 3513 send_packet(ssh, s->pwpkt_type, PKTT_PASSWORD,
3514 PKT_STR, s->password, PKTT_OTHER, PKT_END);
32874aea 3515 }
3516 }
c5e9c988 3517 logevent("Sent password");
51470298 3518 memset(s->password, 0, strlen(s->password));
ff3187f6 3519 crWaitUntil(pktin);
3520 if (pktin->type == SSH1_SMSG_FAILURE) {
32874aea 3521 if (flags & FLAG_VERBOSE)
51470298 3522 c_write_str(ssh, "Access denied\r\n");
c5e9c988 3523 logevent("Authentication refused");
ff3187f6 3524 } else if (pktin->type != SSH1_SMSG_SUCCESS) {
3525 bombout(("Strange packet received, type %d", pktin->type));
7ffdbc1a 3526 crStop(0);
374330e2 3527 }
3528 }
3529
c5e9c988 3530 logevent("Authentication successful");
3531
fb09bf1c 3532 crFinish(1);
3533}
3534
32874aea 3535void sshfwd_close(struct ssh_channel *c)
3536{
51470298 3537 Ssh ssh = c->ssh;
3538
36f94d1f 3539 if (ssh->state != SSH_STATE_SESSION) {
3540 assert(ssh->state == SSH_STATE_CLOSED);
3541 return;
3542 }
3543
80e48603 3544 if (c && !c->closes) {
4ed34d25 3545 /*
3546 * If the channel's remoteid is -1, we have sent
3547 * CHANNEL_OPEN for this channel, but it hasn't even been
3548 * acknowledged by the server. So we must set a close flag
3549 * on it now, and then when the server acks the channel
3550 * open, we can close it then.
3551 */
36cac739 3552 if (((int)c->remoteid) != -1) {
51470298 3553 if (ssh->version == 1) {
3554 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid,
4ed34d25 3555 PKT_END);
3556 } else {
ff3187f6 3557 struct Packet *pktout;
3558 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
3559 ssh2_pkt_adduint32(pktout, c->remoteid);
3560 ssh2_pkt_send(ssh, pktout);
4ed34d25 3561 }
32874aea 3562 }
0357890f 3563 c->closes = 1; /* sent MSG_CLOSE */
32874aea 3564 if (c->type == CHAN_X11) {
3565 c->u.x11.s = NULL;
d74d141c 3566 logevent("Forwarded X11 connection terminated");
4ed34d25 3567 } else if (c->type == CHAN_SOCKDATA ||
3568 c->type == CHAN_SOCKDATA_DORMANT) {
d74d141c 3569 c->u.pfd.s = NULL;
3570 logevent("Forwarded port closed");
32874aea 3571 }
3572 }
3573}
3574
5471d09a 3575int sshfwd_write(struct ssh_channel *c, char *buf, int len)
32874aea 3576{
51470298 3577 Ssh ssh = c->ssh;
3578
36f94d1f 3579 if (ssh->state != SSH_STATE_SESSION) {
3580 assert(ssh->state == SSH_STATE_CLOSED);
3581 return 0;
3582 }
3583
51470298 3584 if (ssh->version == 1) {
3585 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
32874aea 3586 PKT_INT, c->remoteid,
9a10ecf4 3587 PKTT_DATA,
3588 PKT_INT, len, PKT_DATA, buf, len,
3589 PKTT_OTHER, PKT_END);
5471d09a 3590 /*
3591 * In SSH1 we can return 0 here - implying that forwarded
3592 * connections are never individually throttled - because
3593 * the only circumstance that can cause throttling will be
3594 * the whole SSH connection backing up, in which case
3595 * _everything_ will be throttled as a whole.
3596 */
3597 return 0;
783415f8 3598 } else {
32874aea 3599 ssh2_add_channel_data(c, buf, len);
5471d09a 3600 return ssh2_try_send(c);
3601 }
3602}
3603
3604void sshfwd_unthrottle(struct ssh_channel *c, int bufsize)
3605{
51470298 3606 Ssh ssh = c->ssh;
3607
36f94d1f 3608 if (ssh->state != SSH_STATE_SESSION) {
3609 assert(ssh->state == SSH_STATE_CLOSED);
3610 return;
3611 }
3612
51470298 3613 if (ssh->version == 1) {
5471d09a 3614 if (c->v.v1.throttling && bufsize < SSH1_BUFFER_LIMIT) {
3615 c->v.v1.throttling = 0;
51470298 3616 ssh1_throttle(ssh, -1);
5471d09a 3617 }
3618 } else {
3619 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
783415f8 3620 }
9c964e85 3621}
3622
06fadff5 3623static void ssh_queueing_handler(Ssh ssh, struct Packet *pktin)
3624{
3625 struct queued_handler *qh = ssh->qhead;
3626
3627 assert(qh != NULL);
3628
3629 assert(pktin->type == qh->msg1 || pktin->type == qh->msg2);
3630
3631 if (qh->msg1 > 0) {
3632 assert(ssh->packet_dispatch[qh->msg1] == ssh_queueing_handler);
3633 ssh->packet_dispatch[qh->msg1] = NULL;
3634 }
3635 if (qh->msg2 > 0) {
3636 assert(ssh->packet_dispatch[qh->msg2] == ssh_queueing_handler);
3637 ssh->packet_dispatch[qh->msg2] = NULL;
3638 }
3639
3640 if (qh->next) {
3641 ssh->qhead = qh->next;
3642
3643 if (ssh->qhead->msg1 > 0) {
3644 assert(ssh->packet_dispatch[ssh->qhead->msg1] == NULL);
3645 ssh->packet_dispatch[ssh->qhead->msg1] = ssh_queueing_handler;
3646 }
3647 if (ssh->qhead->msg2 > 0) {
3648 assert(ssh->packet_dispatch[ssh->qhead->msg2] == NULL);
3649 ssh->packet_dispatch[ssh->qhead->msg2] = ssh_queueing_handler;
3650 }
3651 } else {
3652 ssh->qhead = ssh->qtail = NULL;
3653 ssh->packet_dispatch[pktin->type] = NULL;
3654 }
3655
3656 qh->handler(ssh, pktin, qh->ctx);
3657
3658 sfree(qh);
3659}
3660
3661static void ssh_queue_handler(Ssh ssh, int msg1, int msg2,
3662 chandler_fn_t handler, void *ctx)
3663{
3664 struct queued_handler *qh;
3665
3666 qh = snew(struct queued_handler);
3667 qh->msg1 = msg1;
3668 qh->msg2 = msg2;
3669 qh->handler = handler;
3670 qh->ctx = ctx;
3671 qh->next = NULL;
3672
3673 if (ssh->qtail == NULL) {
3674 ssh->qhead = qh;
3675
3676 if (qh->msg1 > 0) {
3677 assert(ssh->packet_dispatch[qh->msg1] == NULL);
3678 ssh->packet_dispatch[qh->msg1] = ssh_queueing_handler;
3679 }
3680 if (qh->msg2 > 0) {
3681 assert(ssh->packet_dispatch[qh->msg2] == NULL);
3682 ssh->packet_dispatch[qh->msg2] = ssh_queueing_handler;
3683 }
3684 } else {
3685 ssh->qtail->next = qh;
3686 }
3687 ssh->qtail = qh;
3688}
3689
3690static void ssh_rportfwd_succfail(Ssh ssh, struct Packet *pktin, void *ctx)
3691{
3692 struct ssh_rportfwd *rpf, *pf = (struct ssh_rportfwd *)ctx;
3693
3694 if (pktin->type == (ssh->version == 1 ? SSH1_SMSG_SUCCESS :
3695 SSH2_MSG_REQUEST_SUCCESS)) {
3696 logeventf(ssh, "Remote port forwarding from %s enabled",
3697 pf->sportdesc);
3698 } else {
3699 logeventf(ssh, "Remote port forwarding from %s refused",
3700 pf->sportdesc);
3701
3702 rpf = del234(ssh->rportfwds, pf);
3703 assert(rpf == pf);
fda2feb1 3704 free_rportfwd(pf);
06fadff5 3705 }
3706}
3707
3708static void ssh_setup_portfwd(Ssh ssh, const Config *cfg)
3709{
84328ddb 3710 const char *portfwd_strptr = cfg->portfwd;
3711 struct ssh_portfwd *epf;
3712 int i;
06fadff5 3713
fda2feb1 3714 if (!ssh->portfwds) {
3715 ssh->portfwds = newtree234(ssh_portcmp);
3716 } else {
3717 /*
3718 * Go through the existing port forwardings and tag them
84328ddb 3719 * with status==DESTROY. Any that we want to keep will be
3720 * re-enabled (status==KEEP) as we go through the
3721 * configuration and find out which bits are the same as
3722 * they were before.
fda2feb1 3723 */
3724 struct ssh_portfwd *epf;
3725 int i;
3726 for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
84328ddb 3727 epf->status = DESTROY;
fda2feb1 3728 }
3729
06fadff5 3730 while (*portfwd_strptr) {
84328ddb 3731 char address_family, type;
3732 int sport,dport,sserv,dserv;
3733 char sports[256], dports[256], saddr[256], host[256];
3734 int n;
3735
05581745 3736 address_family = 'A';
3737 type = 'L';
84328ddb 3738 if (*portfwd_strptr == 'A' ||
3739 *portfwd_strptr == '4' ||
3740 *portfwd_strptr == '6')
3741 address_family = *portfwd_strptr++;
3742 if (*portfwd_strptr == 'L' ||
3743 *portfwd_strptr == 'R' ||
3744 *portfwd_strptr == 'D')
3745 type = *portfwd_strptr++;
05581745 3746
06fadff5 3747 saddr[0] = '\0';
05581745 3748
06fadff5 3749 n = 0;
3750 while (*portfwd_strptr && *portfwd_strptr != '\t') {
3751 if (*portfwd_strptr == ':') {
3752 /*
3753 * We've seen a colon in the middle of the
3754 * source port number. This means that
3755 * everything we've seen until now is the
3756 * source _address_, so we'll move it into
3757 * saddr and start sports from the beginning
3758 * again.
3759 */
3760 portfwd_strptr++;
3761 sports[n] = '\0';
3762 if (ssh->version == 1 && type == 'R') {
3763 logeventf(ssh, "SSH1 cannot handle remote source address "
3764 "spec \"%s\"; ignoring", sports);
3765 } else
3766 strcpy(saddr, sports);
3767 n = 0;
3768 }
3769 if (n < 255) sports[n++] = *portfwd_strptr++;
3770 }
3771 sports[n] = 0;
3772 if (type != 'D') {
3773 if (*portfwd_strptr == '\t')
3774 portfwd_strptr++;
3775 n = 0;
3776 while (*portfwd_strptr && *portfwd_strptr != ':') {
3777 if (n < 255) host[n++] = *portfwd_strptr++;
3778 }
3779 host[n] = 0;
3780 if (*portfwd_strptr == ':')
3781 portfwd_strptr++;
3782 n = 0;
3783 while (*portfwd_strptr) {
3784 if (n < 255) dports[n++] = *portfwd_strptr++;
3785 }
3786 dports[n] = 0;
3787 portfwd_strptr++;
3788 dport = atoi(dports);
3789 dserv = 0;
3790 if (dport == 0) {
3791 dserv = 1;
3792 dport = net_service_lookup(dports);
3793 if (!dport) {
3794 logeventf(ssh, "Service lookup failed for destination"
3795 " port \"%s\"", dports);
3796 }
3797 }
3798 } else {
3799 while (*portfwd_strptr) portfwd_strptr++;
3800 dport = dserv = -1;
3801 portfwd_strptr++; /* eat the NUL and move to next one */
3802 }
3803 sport = atoi(sports);
3804 sserv = 0;
3805 if (sport == 0) {
3806 sserv = 1;
3807 sport = net_service_lookup(sports);
3808 if (!sport) {
3809 logeventf(ssh, "Service lookup failed for source"
3810 " port \"%s\"", sports);
3811 }
3812 }
3813 if (sport && dport) {
3814 /* Set up a description of the source port. */
fda2feb1 3815 struct ssh_portfwd *pfrec, *epfrec;
fda2feb1 3816
3817 pfrec = snew(struct ssh_portfwd);
3818 pfrec->type = type;
3819 pfrec->saddr = *saddr ? dupstr(saddr) : NULL;
3fe92132 3820 pfrec->sserv = sserv ? dupstr(sports) : NULL;
fda2feb1 3821 pfrec->sport = sport;
84328ddb 3822 pfrec->daddr = *host ? dupstr(host) : NULL;
3fe92132 3823 pfrec->dserv = dserv ? dupstr(dports) : NULL;
fda2feb1 3824 pfrec->dport = dport;
3825 pfrec->local = NULL;
3826 pfrec->remote = NULL;
05581745 3827 pfrec->addressfamily = (address_family == '4' ? ADDRTYPE_IPV4 :
3828 address_family == '6' ? ADDRTYPE_IPV6 :
3829 ADDRTYPE_UNSPEC);
fda2feb1 3830
3831 epfrec = add234(ssh->portfwds, pfrec);
3832 if (epfrec != pfrec) {
3833 /*
3834 * We already have a port forwarding with precisely
3835 * these parameters. Hence, no need to do anything;
84328ddb 3836 * simply tag the existing one as KEEP.
fda2feb1 3837 */
84328ddb 3838 epfrec->status = KEEP;
fda2feb1 3839 free_portfwd(pfrec);
84328ddb 3840 } else {
3841 pfrec->status = CREATE;
3842 }
3843 }
3844 }
3845
3846 /*
3847 * Now go through and destroy any port forwardings which were
3848 * not re-enabled.
3849 */
3850 for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
3851 if (epf->status == DESTROY) {
3852 char *message;
3853
3854 message = dupprintf("%s port forwarding from %s%s%d",
3855 epf->type == 'L' ? "local" :
3856 epf->type == 'R' ? "remote" : "dynamic",
3857 epf->saddr ? epf->saddr : "",
3858 epf->saddr ? ":" : "",
3859 epf->sport);
3860
3861 if (epf->type != 'D') {
3862 char *msg2 = dupprintf("%s to %s:%d", message,
3863 epf->daddr, epf->dport);
3864 sfree(message);
3865 message = msg2;
3866 }
3867
3868 logeventf(ssh, "Cancelling %s", message);
3869 sfree(message);
3870
3871 if (epf->remote) {
3872 struct ssh_rportfwd *rpf = epf->remote;
3873 struct Packet *pktout;
3874
3875 /*
3876 * Cancel the port forwarding at the server
3877 * end.
3878 */
3879 if (ssh->version == 1) {
3880 /*
3881 * We cannot cancel listening ports on the
3882 * server side in SSH1! There's no message
3883 * to support it. Instead, we simply remove
3884 * the rportfwd record from the local end
3885 * so that any connections the server tries
3886 * to make on it are rejected.
3887 */
3888 } else {
3889 pktout = ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST);
3890 ssh2_pkt_addstring(pktout, "cancel-tcpip-forward");
3891 ssh2_pkt_addbool(pktout, 0);/* _don't_ want reply */
3892 if (epf->saddr) {
3893 ssh2_pkt_addstring(pktout, epf->saddr);
3894 } else if (ssh->cfg.rport_acceptall) {
3895 ssh2_pkt_addstring(pktout, "0.0.0.0");
3896 } else {
3897 ssh2_pkt_addstring(pktout, "127.0.0.1");
3898 }
3899 ssh2_pkt_adduint32(pktout, epf->sport);
3900 ssh2_pkt_send(ssh, pktout);
3901 }
3902
3903 del234(ssh->rportfwds, rpf);
3904 free_rportfwd(rpf);
3905 } else if (epf->local) {
3906 pfd_terminate(epf->local);
3907 }
3908
3909 delpos234(ssh->portfwds, i);
3910 free_portfwd(epf);
3911 i--; /* so we don't skip one in the list */
3912 }
3913
3914 /*
3915 * And finally, set up any new port forwardings (status==CREATE).
3916 */
3917 for (i = 0; (epf = index234(ssh->portfwds, i)) != NULL; i++)
3918 if (epf->status == CREATE) {
3919 char *sportdesc, *dportdesc;
3fe92132 3920 sportdesc = dupprintf("%s%s%s%s%d%s",
84328ddb 3921 epf->saddr ? epf->saddr : "",
3922 epf->saddr ? ":" : "",
3fe92132 3923 epf->sserv ? epf->sserv : "",
3924 epf->sserv ? "(" : "",
3925 epf->sport,
3926 epf->sserv ? ")" : "");
84328ddb 3927 if (epf->type == 'D') {
3928 dportdesc = NULL;
3929 } else {
3fe92132 3930 dportdesc = dupprintf("%s:%s%s%d%s",
3931 epf->daddr,
3932 epf->dserv ? epf->dserv : "",
3933 epf->dserv ? "(" : "",
3934 epf->dport,
3935 epf->dserv ? ")" : "");
84328ddb 3936 }
05581745 3937
84328ddb 3938 if (epf->type == 'L') {
3939 const char *err = pfd_addforward(epf->daddr, epf->dport,
3940 epf->saddr, epf->sport,
3941 ssh, &ssh->cfg,
3942 &epf->local,
3943 epf->addressfamily);
3944
3945 logeventf(ssh, "Local %sport %s forwarding to %s%s%s",
3946 epf->addressfamily == ADDRTYPE_IPV4 ? "IPv4 " :
3947 epf->addressfamily == ADDRTYPE_IPV6 ? "IPv6 " : "",
3948 sportdesc, dportdesc,
3949 err ? " failed: " : "", err ? err : "");
3950 } else if (epf->type == 'D') {
06fadff5 3951 const char *err = pfd_addforward(NULL, -1,
84328ddb 3952 epf->saddr, epf->sport,
3953 ssh, &ssh->cfg,
3954 &epf->local,
3955 epf->addressfamily);
3956
3957 logeventf(ssh, "Local %sport %s SOCKS dynamic forwarding%s%s",
3958 epf->addressfamily == ADDRTYPE_IPV4 ? "IPv4 " :
3959 epf->addressfamily == ADDRTYPE_IPV6 ? "IPv6 " : "",
3960 sportdesc,
3961 err ? " failed: " : "", err ? err : "");
06fadff5 3962 } else {
3963 struct ssh_rportfwd *pf;
3964
3965 /*
3966 * Ensure the remote port forwardings tree exists.
3967 */
3968 if (!ssh->rportfwds) {
3969 if (ssh->version == 1)
3970 ssh->rportfwds = newtree234(ssh_rportcmp_ssh1);
3971 else
3972 ssh->rportfwds = newtree234(ssh_rportcmp_ssh2);
3973 }
3974
3975 pf = snew(struct ssh_rportfwd);
84328ddb 3976 strncpy(pf->dhost, epf->daddr, lenof(pf->dhost)-1);
3977 pf->dhost[lenof(pf->dhost)-1] = '\0';
3978 pf->dport = epf->dport;
3979 pf->sport = epf->sport;
06fadff5 3980 if (add234(ssh->rportfwds, pf) != pf) {
3981 logeventf(ssh, "Duplicate remote port forwarding to %s:%d",
84328ddb 3982 epf->daddr, epf->dport);
06fadff5 3983 sfree(pf);
3984 } else {
3985 logeventf(ssh, "Requesting remote port %s"
84328ddb 3986 " forward to %s", sportdesc, dportdesc);
06fadff5 3987
3988 pf->sportdesc = sportdesc;
3989 sportdesc = NULL;
84328ddb 3990 epf->remote = pf;
3991 pf->pfrec = epf;
06fadff5 3992
3993 if (ssh->version == 1) {
3994 send_packet(ssh, SSH1_CMSG_PORT_FORWARD_REQUEST,
84328ddb 3995 PKT_INT, epf->sport,
3996 PKT_STR, epf->daddr,
3997 PKT_INT, epf->dport,
06fadff5 3998 PKT_END);
3999 ssh_queue_handler(ssh, SSH1_SMSG_SUCCESS,
4000 SSH1_SMSG_FAILURE,
4001 ssh_rportfwd_succfail, pf);
4002 } else {
4003 struct Packet *pktout;
4004 pktout = ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST);
4005 ssh2_pkt_addstring(pktout, "tcpip-forward");
4006 ssh2_pkt_addbool(pktout, 1);/* want reply */
84328ddb 4007 if (epf->saddr) {
4008 ssh2_pkt_addstring(pktout, epf->saddr);
06fadff5 4009 } else if (ssh->cfg.rport_acceptall) {
4010 ssh2_pkt_addstring(pktout, "0.0.0.0");
4011 } else {
4012 ssh2_pkt_addstring(pktout, "127.0.0.1");
4013 }
84328ddb 4014 ssh2_pkt_adduint32(pktout, epf->sport);
06fadff5 4015 ssh2_pkt_send(ssh, pktout);
4016
4017 ssh_queue_handler(ssh, SSH2_MSG_REQUEST_SUCCESS,
4018 SSH2_MSG_REQUEST_FAILURE,
4019 ssh_rportfwd_succfail, pf);
4020 }
4021 }
4022 }
4023 sfree(sportdesc);
84328ddb 4024 sfree(dportdesc);
06fadff5 4025 }
06fadff5 4026}
4027
51df0ab5 4028static void ssh1_smsg_stdout_stderr_data(Ssh ssh, struct Packet *pktin)
4029{
4030 char *string;
4031 int stringlen, bufsize;
4032
4033 ssh_pkt_getstring(pktin, &string, &stringlen);
4034 if (string == NULL) {
4035 bombout(("Incoming terminal data packet was badly formed"));
4036 return;
4037 }
4038
4039 bufsize = from_backend(ssh->frontend, pktin->type == SSH1_SMSG_STDERR_DATA,
4040 string, stringlen);
4041 if (!ssh->v1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
4042 ssh->v1_stdout_throttling = 1;
4043 ssh1_throttle(ssh, +1);
4044 }
4045}
4046
4047static void ssh1_smsg_x11_open(Ssh ssh, struct Packet *pktin)
4048{
4049 /* Remote side is trying to open a channel to talk to our
4050 * X-Server. Give them back a local channel number. */
4051 struct ssh_channel *c;
4052 int remoteid = ssh_pkt_getuint32(pktin);
4053
4054 logevent("Received X11 connect request");
4055 /* Refuse if X11 forwarding is disabled. */
4056 if (!ssh->X11_fwd_enabled) {
4057 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4058 PKT_INT, remoteid, PKT_END);
4059 logevent("Rejected X11 connect request");
4060 } else {
4061 c = snew(struct ssh_channel);
4062 c->ssh = ssh;
4063
4064 if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
4065 ssh->x11auth, NULL, -1, &ssh->cfg) != NULL) {
4066 logevent("Opening X11 forward connection failed");
4067 sfree(c);
4068 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4069 PKT_INT, remoteid, PKT_END);
4070 } else {
4071 logevent
4072 ("Opening X11 forward connection succeeded");
4073 c->remoteid = remoteid;
4074 c->localid = alloc_channel_id(ssh);
4075 c->closes = 0;
4076 c->v.v1.throttling = 0;
4077 c->type = CHAN_X11; /* identify channel type */
4078 add234(ssh->channels, c);
4079 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
4080 PKT_INT, c->remoteid, PKT_INT,
4081 c->localid, PKT_END);
4082 logevent("Opened X11 forward channel");
4083 }
4084 }
4085}
4086
4087static void ssh1_smsg_agent_open(Ssh ssh, struct Packet *pktin)
4088{
4089 /* Remote side is trying to open a channel to talk to our
4090 * agent. Give them back a local channel number. */
4091 struct ssh_channel *c;
4092 int remoteid = ssh_pkt_getuint32(pktin);
4093
4094 /* Refuse if agent forwarding is disabled. */
4095 if (!ssh->agentfwd_enabled) {
4096 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4097 PKT_INT, remoteid, PKT_END);
4098 } else {
4099 c = snew(struct ssh_channel);
4100 c->ssh = ssh;
4101 c->remoteid = remoteid;
4102 c->localid = alloc_channel_id(ssh);
4103 c->closes = 0;
4104 c->v.v1.throttling = 0;
4105 c->type = CHAN_AGENT; /* identify channel type */
4106 c->u.a.lensofar = 0;
4107 add234(ssh->channels, c);
4108 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
4109 PKT_INT, c->remoteid, PKT_INT, c->localid,
4110 PKT_END);
4111 }
4112}
4113
4114static void ssh1_msg_port_open(Ssh ssh, struct Packet *pktin)
4115{
4116 /* Remote side is trying to open a channel to talk to a
4117 * forwarded port. Give them back a local channel number. */
4118 struct ssh_channel *c;
05581745 4119 struct ssh_rportfwd pf, *pfp;
51df0ab5 4120 int remoteid;
4121 int hostsize, port;
4122 char *host, buf[1024];
4123 const char *e;
4124 c = snew(struct ssh_channel);
4125 c->ssh = ssh;
4126
4127 remoteid = ssh_pkt_getuint32(pktin);
4128 ssh_pkt_getstring(pktin, &host, &hostsize);
4129 port = ssh_pkt_getuint32(pktin);
4130
4131 if (hostsize >= lenof(pf.dhost))
4132 hostsize = lenof(pf.dhost)-1;
4133 memcpy(pf.dhost, host, hostsize);
4134 pf.dhost[hostsize] = '\0';
4135 pf.dport = port;
05581745 4136 pfp = find234(ssh->rportfwds, &pf, NULL);
51df0ab5 4137
05581745 4138 if (pfp == NULL) {
51df0ab5 4139 sprintf(buf, "Rejected remote port open request for %s:%d",
4140 pf.dhost, port);
4141 logevent(buf);
4142 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4143 PKT_INT, remoteid, PKT_END);
4144 } else {
4145 sprintf(buf, "Received remote port open request for %s:%d",
4146 pf.dhost, port);
4147 logevent(buf);
4148 e = pfd_newconnect(&c->u.pfd.s, pf.dhost, port,
05581745 4149 c, &ssh->cfg, pfp->pfrec->addressfamily);
51df0ab5 4150 if (e != NULL) {
4151 char buf[256];
4152 sprintf(buf, "Port open failed: %s", e);
4153 logevent(buf);
4154 sfree(c);
4155 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
4156 PKT_INT, remoteid, PKT_END);
4157 } else {
4158 c->remoteid = remoteid;
4159 c->localid = alloc_channel_id(ssh);
4160 c->closes = 0;
4161 c->v.v1.throttling = 0;
4162 c->type = CHAN_SOCKDATA; /* identify channel type */
4163 add234(ssh->channels, c);
4164 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
4165 PKT_INT, c->remoteid, PKT_INT,
4166 c->localid, PKT_END);
4167 logevent("Forwarded port opened successfully");
4168 }
4169 }
4170}
4171
4172static void ssh1_msg_channel_open_confirmation(Ssh ssh, struct Packet *pktin)
4173{
4174 unsigned int remoteid = ssh_pkt_getuint32(pktin);
4175 unsigned int localid = ssh_pkt_getuint32(pktin);
4176 struct ssh_channel *c;
4177
4178 c = find234(ssh->channels, &remoteid, ssh_channelfind);
4179 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
4180 c->remoteid = localid;
4181 c->type = CHAN_SOCKDATA;
4182 c->v.v1.throttling = 0;
4183 pfd_confirm(c->u.pfd.s);
4184 }
4185
4186 if (c && c->closes) {
4187 /*
4188 * We have a pending close on this channel,
4189 * which we decided on before the server acked
4190 * the channel open. So now we know the
4191 * remoteid, we can close it again.
4192 */
4193 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE,
4194 PKT_INT, c->remoteid, PKT_END);
4195 }
4196}
4197
4198static void ssh1_msg_channel_open_failure(Ssh ssh, struct Packet *pktin)
4199{
4200 unsigned int remoteid = ssh_pkt_getuint32(pktin);
4201 struct ssh_channel *c;
4202
4203 c = find234(ssh->channels, &remoteid, ssh_channelfind);
4204 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
4205 logevent("Forwarded connection refused by server");
4206 pfd_close(c->u.pfd.s);
4207 del234(ssh->channels, c);
4208 sfree(c);
4209 }
4210}
4211
4212static void ssh1_msg_channel_close(Ssh ssh, struct Packet *pktin)
4213{
4214 /* Remote side closes a channel. */
4215 unsigned i = ssh_pkt_getuint32(pktin);
4216 struct ssh_channel *c;
4217 c = find234(ssh->channels, &i, ssh_channelfind);
4218 if (c && ((int)c->remoteid) != -1) {
4219 int closetype;
4220 closetype =
4221 (pktin->type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
4222
4223 if ((c->closes == 0) && (c->type == CHAN_X11)) {
4224 logevent("Forwarded X11 connection terminated");
4225 assert(c->u.x11.s != NULL);
4226 x11_close(c->u.x11.s);
4227 c->u.x11.s = NULL;
4228 }
4229 if ((c->closes == 0) && (c->type == CHAN_SOCKDATA)) {
4230 logevent("Forwarded port closed");
4231 assert(c->u.pfd.s != NULL);
4232 pfd_close(c->u.pfd.s);
4233 c->u.pfd.s = NULL;
4234 }
4235
4236 c->closes |= (closetype << 2); /* seen this message */
4237 if (!(c->closes & closetype)) {
4238 send_packet(ssh, pktin->type, PKT_INT, c->remoteid,
4239 PKT_END);
4240 c->closes |= closetype; /* sent it too */
4241 }
4242
4243 if (c->closes == 15) {
4244 del234(ssh->channels, c);
4245 sfree(c);
4246 }
4247 } else {
4248 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
4249 pktin->type == SSH1_MSG_CHANNEL_CLOSE ? "" :
4250 "_CONFIRMATION", c ? "half-open" : "nonexistent",
4251 i));
4252 }
4253}
4254
4255static void ssh1_msg_channel_data(Ssh ssh, struct Packet *pktin)
4256{
4257 /* Data sent down one of our channels. */
4258 int i = ssh_pkt_getuint32(pktin);
4259 char *p;
aa63ab7e 4260 unsigned int len;
51df0ab5 4261 struct ssh_channel *c;
4262
4263 ssh_pkt_getstring(pktin, &p, &len);
4264
4265 c = find234(ssh->channels, &i, ssh_channelfind);
4266 if (c) {
4267 int bufsize = 0;
4268 switch (c->type) {
4269 case CHAN_X11:
4270 bufsize = x11_send(c->u.x11.s, p, len);
4271 break;
4272 case CHAN_SOCKDATA:
4273 bufsize = pfd_send(c->u.pfd.s, p, len);
4274 break;
4275 case CHAN_AGENT:
4276 /* Data for an agent message. Buffer it. */
4277 while (len > 0) {
4278 if (c->u.a.lensofar < 4) {
aa63ab7e 4279 unsigned int l = min(4 - c->u.a.lensofar, len);
51df0ab5 4280 memcpy(c->u.a.msglen + 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 == 4) {
4287 c->u.a.totallen =
4288 4 + GET_32BIT(c->u.a.msglen);
4289 c->u.a.message = snewn(c->u.a.totallen,
4290 unsigned char);
4291 memcpy(c->u.a.message, c->u.a.msglen, 4);
4292 }
4293 if (c->u.a.lensofar >= 4 && len > 0) {
aa63ab7e 4294 unsigned int l =
51df0ab5 4295 min(c->u.a.totallen - c->u.a.lensofar,
4296 len);
4297 memcpy(c->u.a.message + c->u.a.lensofar, p,
4298 l);
4299 p += l;
4300 len -= l;
4301 c->u.a.lensofar += l;
4302 }
4303 if (c->u.a.lensofar == c->u.a.totallen) {
4304 void *reply;
4305 int replylen;
4306 if (agent_query(c->u.a.message,
4307 c->u.a.totallen,
4308 &reply, &replylen,
4309 ssh_agentf_callback, c))
4310 ssh_agentf_callback(c, reply, replylen);
4311 sfree(c->u.a.message);
4312 c->u.a.lensofar = 0;
4313 }
4314 }
4315 bufsize = 0; /* agent channels never back up */
4316 break;
4317 }
4318 if (!c->v.v1.throttling && bufsize > SSH1_BUFFER_LIMIT) {
4319 c->v.v1.throttling = 1;
4320 ssh1_throttle(ssh, +1);
4321 }
4322 }
4323}
4324
4325static void ssh1_smsg_exit_status(Ssh ssh, struct Packet *pktin)
4326{
4327 char buf[100];
4328 ssh->exitcode = ssh_pkt_getuint32(pktin);
4329 sprintf(buf, "Server sent command exit status %d",
4330 ssh->exitcode);
4331 logevent(buf);
4332 send_packet(ssh, SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
4333 /*
4334 * In case `helpful' firewalls or proxies tack
4335 * extra human-readable text on the end of the
4336 * session which we might mistake for another
4337 * encrypted packet, we close the session once
4338 * we've sent EXIT_CONFIRMATION.
4339 */
ac934965 4340 ssh->close_expected = TRUE;
51df0ab5 4341 ssh_closing((Plug)ssh, NULL, 0, 0);
4342}
4343
b09eaa88 4344static void do_ssh1_connection(Ssh ssh, unsigned char *in, int inlen,
4345 struct Packet *pktin)
32874aea 4346{
b09eaa88 4347 crBegin(ssh->do_ssh1_connection_crstate);
fb09bf1c 4348
51df0ab5 4349 ssh->packet_dispatch[SSH1_SMSG_STDOUT_DATA] =
4350 ssh->packet_dispatch[SSH1_SMSG_STDERR_DATA] =
4351 ssh1_smsg_stdout_stderr_data;
4352
4353 ssh->packet_dispatch[SSH1_MSG_CHANNEL_OPEN_CONFIRMATION] =
4354 ssh1_msg_channel_open_confirmation;
4355 ssh->packet_dispatch[SSH1_MSG_CHANNEL_OPEN_FAILURE] =
4356 ssh1_msg_channel_open_failure;
4357 ssh->packet_dispatch[SSH1_MSG_CHANNEL_CLOSE] =
4358 ssh->packet_dispatch[SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION] =
4359 ssh1_msg_channel_close;
4360 ssh->packet_dispatch[SSH1_MSG_CHANNEL_DATA] = ssh1_msg_channel_data;
4361 ssh->packet_dispatch[SSH1_SMSG_EXIT_STATUS] = ssh1_smsg_exit_status;
4362
86916870 4363 if (ssh->cfg.agentfwd && agent_exists()) {
32874aea 4364 logevent("Requesting agent forwarding");
51470298 4365 send_packet(ssh, SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
32874aea 4366 do {
4367 crReturnV;
ff3187f6 4368 } while (!pktin);
4369 if (pktin->type != SSH1_SMSG_SUCCESS
4370 && pktin->type != SSH1_SMSG_FAILURE) {
6b5cf8b4 4371 bombout(("Protocol confusion"));
7ffdbc1a 4372 crStopV;
ff3187f6 4373 } else if (pktin->type == SSH1_SMSG_FAILURE) {
32874aea 4374 logevent("Agent forwarding refused");
4375 } else {
4376 logevent("Agent forwarding enabled");
51470298 4377 ssh->agentfwd_enabled = TRUE;
51df0ab5 4378 ssh->packet_dispatch[SSH1_SMSG_AGENT_OPEN] = ssh1_smsg_agent_open;
db7d555c 4379 }
dacbd0e8 4380 }
4381
86916870 4382 if (ssh->cfg.x11_forward) {
32874aea 4383 char proto[20], data[64];
4384 logevent("Requesting X11 forwarding");
302121de 4385 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
86916870 4386 data, sizeof(data), ssh->cfg.x11_auth);
4387 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
51470298 4388 if (ssh->v1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) {
4389 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
32874aea 4390 PKT_STR, proto, PKT_STR, data,
86916870 4391 PKT_INT, x11_get_screen_number(ssh->cfg.x11_display),
421d6835 4392 PKT_END);
32874aea 4393 } else {
51470298 4394 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
32874aea 4395 PKT_STR, proto, PKT_STR, data, PKT_END);
4396 }
4397 do {
4398 crReturnV;
ff3187f6 4399 } while (!pktin);
4400 if (pktin->type != SSH1_SMSG_SUCCESS
4401 && pktin->type != SSH1_SMSG_FAILURE) {
6b5cf8b4 4402 bombout(("Protocol confusion"));
7ffdbc1a 4403 crStopV;
ff3187f6 4404 } else if (pktin->type == SSH1_SMSG_FAILURE) {
32874aea 4405 logevent("X11 forwarding refused");
4406 } else {
4407 logevent("X11 forwarding enabled");
51470298 4408 ssh->X11_fwd_enabled = TRUE;
51df0ab5 4409 ssh->packet_dispatch[SSH1_SMSG_X11_OPEN] = ssh1_smsg_x11_open;
9c964e85 4410 }
4411 }
4412
06fadff5 4413 ssh_setup_portfwd(ssh, &ssh->cfg);
4414 ssh->packet_dispatch[SSH1_MSG_PORT_OPEN] = ssh1_msg_port_open;
d74d141c 4415
86916870 4416 if (!ssh->cfg.nopty) {
a5dd8467 4417 /* Unpick the terminal-speed string. */
4418 /* XXX perhaps we should allow no speeds to be sent. */
db219738 4419 ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
4420 sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
a5dd8467 4421 /* Send the pty request. */
51470298 4422 send_packet(ssh, SSH1_CMSG_REQUEST_PTY,
86916870 4423 PKT_STR, ssh->cfg.termtype,
51470298 4424 PKT_INT, ssh->term_height,
4425 PKT_INT, ssh->term_width,
a5dd8467 4426 PKT_INT, 0, PKT_INT, 0, /* width,height in pixels */
db219738 4427 PKT_CHAR, 192, PKT_INT, ssh->ispeed, /* TTY_OP_ISPEED */
4428 PKT_CHAR, 193, PKT_INT, ssh->ospeed, /* TTY_OP_OSPEED */
a5dd8467 4429 PKT_CHAR, 0, PKT_END);
51470298 4430 ssh->state = SSH_STATE_INTERMED;
32874aea 4431 do {
4432 crReturnV;
ff3187f6 4433 } while (!pktin);
4434 if (pktin->type != SSH1_SMSG_SUCCESS
4435 && pktin->type != SSH1_SMSG_FAILURE) {
6b5cf8b4 4436 bombout(("Protocol confusion"));
7ffdbc1a 4437 crStopV;
ff3187f6 4438 } else if (pktin->type == SSH1_SMSG_FAILURE) {
51470298 4439 c_write_str(ssh, "Server refused to allocate pty\r\n");
4440 ssh->editing = ssh->echoing = 1;
32874aea 4441 }
a5dd8467 4442 logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
db219738 4443 ssh->ospeed, ssh->ispeed);
0965bee0 4444 } else {
51470298 4445 ssh->editing = ssh->echoing = 1;
374330e2 4446 }
4447
86916870 4448 if (ssh->cfg.compression) {
51470298 4449 send_packet(ssh, SSH1_CMSG_REQUEST_COMPRESSION, PKT_INT, 6, PKT_END);
32874aea 4450 do {
4451 crReturnV;
ff3187f6 4452 } while (!pktin);
4453 if (pktin->type != SSH1_SMSG_SUCCESS
4454 && pktin->type != SSH1_SMSG_FAILURE) {
6b5cf8b4 4455 bombout(("Protocol confusion"));
7ffdbc1a 4456 crStopV;
ff3187f6 4457 } else if (pktin->type == SSH1_SMSG_FAILURE) {
51470298 4458 c_write_str(ssh, "Server refused to compress\r\n");
32874aea 4459 }
4ba9b64b 4460 logevent("Started compression");
51470298 4461 ssh->v1_compressing = TRUE;
5366aed8 4462 ssh->cs_comp_ctx = zlib_compress_init();
4463 logevent("Initialised zlib (RFC1950) compression");
4464 ssh->sc_comp_ctx = zlib_decompress_init();
4465 logevent("Initialised zlib (RFC1950) decompression");
4ba9b64b 4466 }
4467
fd5e5847 4468 /*
4469 * Start the shell or command.
4470 *
4471 * Special case: if the first-choice command is an SSH2
4472 * subsystem (hence not usable here) and the second choice
4473 * exists, we fall straight back to that.
4474 */
4475 {
86916870 4476 char *cmd = ssh->cfg.remote_cmd_ptr;
fd5e5847 4477
86916870 4478 if (ssh->cfg.ssh_subsys && ssh->cfg.remote_cmd_ptr2) {
4479 cmd = ssh->cfg.remote_cmd_ptr2;
51470298 4480 ssh->fallback_cmd = TRUE;
fd5e5847 4481 }
4482 if (*cmd)
51470298 4483 send_packet(ssh, SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END);
fd5e5847 4484 else
51470298 4485 send_packet(ssh, SSH1_CMSG_EXEC_SHELL, PKT_END);
fd5e5847 4486 logevent("Started session");
4487 }
374330e2 4488
51470298 4489 ssh->state = SSH_STATE_SESSION;
4490 if (ssh->size_needed)
4491 ssh_size(ssh, ssh->term_width, ssh->term_height);
4492 if (ssh->eof_needed)
4493 ssh_special(ssh, TS_EOF);
374330e2 4494
b9d7bcad 4495 if (ssh->ldisc)
4496 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
51470298 4497 ssh->send_ok = 1;
4498 ssh->channels = newtree234(ssh_channelcmp);
374330e2 4499 while (1) {
d74d141c 4500
51df0ab5 4501 /*
4502 * By this point, most incoming packets are already being
4503 * handled by the dispatch table, and we need only pay
4504 * attention to the unusual ones.
4505 */
0357890f 4506
51df0ab5 4507 crReturnV;
4508 if (pktin) {
4509 if (pktin->type == SSH1_SMSG_SUCCESS) {
972a41c8 4510 /* may be from EXEC_SHELL on some servers */
ff3187f6 4511 } else if (pktin->type == SSH1_SMSG_FAILURE) {
972a41c8 4512 /* may be from EXEC_SHELL on some servers
374330e2 4513 * if no pty is available or in other odd cases. Ignore */
374330e2 4514 } else {
ff3187f6 4515 bombout(("Strange packet received: type %d", pktin->type));
7ffdbc1a 4516 crStopV;
374330e2 4517 }
4518 } else {
8df7a775 4519 while (inlen > 0) {
4520 int len = min(inlen, 512);
9a10ecf4 4521 send_packet(ssh, SSH1_CMSG_STDIN_DATA, PKTT_DATA,
4522 PKT_INT, len, PKT_DATA, in, len,
4523 PKTT_OTHER, PKT_END);
8df7a775 4524 in += len;
4525 inlen -= len;
4526 }
374330e2 4527 }
4528 }
4529
4530 crFinishV;
4531}
4532
4533/*
b09eaa88 4534 * Handle the top-level SSH2 protocol.
4535 */
4536static void ssh1_msg_debug(Ssh ssh, struct Packet *pktin)
4537{
4538 char *buf, *msg;
4539 int msglen;
4540
4541 ssh_pkt_getstring(pktin, &msg, &msglen);
4542 buf = dupprintf("Remote debug message: %.*s", msglen, msg);
4543 logevent(buf);
4544 sfree(buf);
4545}
4546
4547static void ssh1_msg_disconnect(Ssh ssh, struct Packet *pktin)
4548{
4549 /* log reason code in disconnect message */
4550 char *msg;
4551 int msglen;
4552
4553 ssh_pkt_getstring(pktin, &msg, &msglen);
4554 bombout(("Server sent disconnect message:\n\"%.*s\"", msglen, msg));
4555}
4556
4557void ssh_msg_ignore(Ssh ssh, struct Packet *pktin)
4558{
4559 /* Do nothing, because we're ignoring it! Duhh. */
4560}
4561
4562static void ssh1_protocol_setup(Ssh ssh)
4563{
4564 int i;
4565
4566 /*
4567 * Most messages are handled by the coroutines.
4568 */
4569 for (i = 0; i < 256; i++)
4570 ssh->packet_dispatch[i] = NULL;
4571
4572 /*
4573 * These special message types we install handlers for.
4574 */
4575 ssh->packet_dispatch[SSH1_MSG_DISCONNECT] = ssh1_msg_disconnect;
4576 ssh->packet_dispatch[SSH1_MSG_IGNORE] = ssh_msg_ignore;
4577 ssh->packet_dispatch[SSH1_MSG_DEBUG] = ssh1_msg_debug;
4578}
4579
4580static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen,
4581 struct Packet *pktin)
4582{
4583 if (ssh->state == SSH_STATE_CLOSED)
4584 return;
4585
4586 if (pktin && ssh->packet_dispatch[pktin->type]) {
4587 ssh->packet_dispatch[pktin->type](ssh, pktin);
4588 return;
4589 }
4590
4591 if (!ssh->protocol_initial_phase_done) {
4592 if (do_ssh1_login(ssh, in, inlen, pktin))
4593 ssh->protocol_initial_phase_done = TRUE;
4594 else
4595 return;
4596 }
4597
4598 do_ssh1_connection(ssh, in, inlen, pktin);
4599}
4600
4601/*
e5574168 4602 * Utility routine for decoding comma-separated strings in KEXINIT.
4603 */
32874aea 4604static int in_commasep_string(char *needle, char *haystack, int haylen)
4605{
57356d63 4606 int needlen;
4607 if (!needle || !haystack) /* protect against null pointers */
4608 return 0;
4609 needlen = strlen(needle);
e5574168 4610 while (1) {
32874aea 4611 /*
4612 * Is it at the start of the string?
4613 */
4614 if (haylen >= needlen && /* haystack is long enough */
4615 !memcmp(needle, haystack, needlen) && /* initial match */
4616 (haylen == needlen || haystack[needlen] == ',')
4617 /* either , or EOS follows */
4618 )
4619 return 1;
4620 /*
4621 * If not, search for the next comma and resume after that.
4622 * If no comma found, terminate.
4623 */
4624 while (haylen > 0 && *haystack != ',')
4625 haylen--, haystack++;
4626 if (haylen == 0)
4627 return 0;
4628 haylen--, haystack++; /* skip over comma itself */
e5574168 4629 }
4630}
4631
4632/*
d39f364a 4633 * SSH2 key creation method.
4634 */
d8baa528 4635static void ssh2_mkkey(Ssh ssh, Bignum K, unsigned char *H,
4636 unsigned char *sessid, char chr,
4637 unsigned char *keyspace)
32874aea 4638{
d39f364a 4639 SHA_State s;
4640 /* First 20 bytes. */
4641 SHA_Init(&s);
51470298 4642 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
088bde77 4643 sha_mpint(&s, K);
d39f364a 4644 SHA_Bytes(&s, H, 20);
4645 SHA_Bytes(&s, &chr, 1);
5e0d7cb8 4646 SHA_Bytes(&s, sessid, 20);
d39f364a 4647 SHA_Final(&s, keyspace);
4648 /* Next 20 bytes. */
4649 SHA_Init(&s);
51470298 4650 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
088bde77 4651 sha_mpint(&s, K);
d39f364a 4652 SHA_Bytes(&s, H, 20);
4653 SHA_Bytes(&s, keyspace, 20);
32874aea 4654 SHA_Final(&s, keyspace + 20);
d39f364a 4655}
4656
4657/*
7cca0d81 4658 * Handle the SSH2 transport layer.
e5574168 4659 */
ff3187f6 4660static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen,
4661 struct Packet *pktin)
e5574168 4662{
51470298 4663 struct do_ssh2_transport_state {
4664 int nbits, pbits, warn;
4665 Bignum p, g, e, f, K;
4666 int kex_init_value, kex_reply_value;
4667 const struct ssh_mac **maclist;
4668 int nmacs;
4669 const struct ssh2_cipher *cscipher_tobe;
4670 const struct ssh2_cipher *sccipher_tobe;
4671 const struct ssh_mac *csmac_tobe;
4672 const struct ssh_mac *scmac_tobe;
4673 const struct ssh_compress *cscomp_tobe;
4674 const struct ssh_compress *sccomp_tobe;
4675 char *hostkeydata, *sigdata, *keystr, *fingerprint;
4676 int hostkeylen, siglen;
4677 void *hkey; /* actual host key */
4678 unsigned char exchange_hash[20];
83e7d008 4679 int n_preferred_kex;
4680 const struct ssh_kex *preferred_kex[KEX_MAX];
51470298 4681 int n_preferred_ciphers;
4682 const struct ssh2_ciphers *preferred_ciphers[CIPHER_MAX];
4683 const struct ssh_compress *preferred_comp;
e13bba36 4684 int got_session_id, activated_authconn;
ff3187f6 4685 struct Packet *pktout;
51470298 4686 };
4687 crState(do_ssh2_transport_state);
4688
4689 crBegin(ssh->do_ssh2_transport_crstate);
4690
4691 s->cscipher_tobe = s->sccipher_tobe = NULL;
4692 s->csmac_tobe = s->scmac_tobe = NULL;
4693 s->cscomp_tobe = s->sccomp_tobe = NULL;
4694
e13bba36 4695 s->got_session_id = s->activated_authconn = FALSE;
e5574168 4696
e13bba36 4697 /*
4698 * Be prepared to work around the buggy MAC problem.
4699 */
4700 if (ssh->remote_bugs & BUG_SSH2_HMAC)
4701 s->maclist = buggymacs, s->nmacs = lenof(buggymacs);
4702 else
4703 s->maclist = macs, s->nmacs = lenof(macs);
4704
4705 begin_key_exchange:
149d2abc 4706 ssh->pkt_ctx &= ~SSH2_PKTCTX_KEX_MASK;
51470298 4707 {
e13bba36 4708 int i, j, commalist_started;
4709
51470298 4710 /*
83e7d008 4711 * Set up the preferred key exchange. (NULL => warn below here)
4712 */
4713 s->n_preferred_kex = 0;
4714 for (i = 0; i < KEX_MAX; i++) {
4715 switch (ssh->cfg.ssh_kexlist[i]) {
4716 case KEX_DHGEX:
4717 s->preferred_kex[s->n_preferred_kex++] =
4718 &ssh_diffiehellman_gex;
4719 break;
4720 case KEX_DHGROUP14:
4721 s->preferred_kex[s->n_preferred_kex++] =
4722 &ssh_diffiehellman_group14;
4723 break;
4724 case KEX_DHGROUP1:
4725 s->preferred_kex[s->n_preferred_kex++] =
4726 &ssh_diffiehellman_group1;
4727 break;
4728 case CIPHER_WARN:
4729 /* Flag for later. Don't bother if it's the last in
4730 * the list. */
4731 if (i < KEX_MAX - 1) {
4732 s->preferred_kex[s->n_preferred_kex++] = NULL;
4733 }
4734 break;
4735 }
4736 }
83e7d008 4737
83e7d008 4738 /*
51470298 4739 * Set up the preferred ciphers. (NULL => warn below here)
4740 */
4741 s->n_preferred_ciphers = 0;
4742 for (i = 0; i < CIPHER_MAX; i++) {
86916870 4743 switch (ssh->cfg.ssh_cipherlist[i]) {
51470298 4744 case CIPHER_BLOWFISH:
4745 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_blowfish;
4746 break;
4747 case CIPHER_DES:
86916870 4748 if (ssh->cfg.ssh2_des_cbc) {
51470298 4749 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_des;
4750 }
4751 break;
4752 case CIPHER_3DES:
4753 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_3des;
4754 break;
4755 case CIPHER_AES:
4756 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_aes;
4757 break;
4758 case CIPHER_WARN:
4759 /* Flag for later. Don't bother if it's the last in
4760 * the list. */
4761 if (i < CIPHER_MAX - 1) {
4762 s->preferred_ciphers[s->n_preferred_ciphers++] = NULL;
4763 }
4764 break;
ca20bfcf 4765 }
ca20bfcf 4766 }
7591b9ff 4767
e13bba36 4768 /*
4769 * Set up preferred compression.
4770 */
4771 if (ssh->cfg.compression)
4772 s->preferred_comp = &ssh_zlib;
4773 else
4774 s->preferred_comp = &ssh_comp_none;
51470298 4775
4776 /*
590f6a5f 4777 * Enable queueing of outgoing auth- or connection-layer
4778 * packets while we are in the middle of a key exchange.
4779 */
4780 ssh->queueing = TRUE;
4781
4782 /*
9442dd57 4783 * Flag that KEX is in progress.
4784 */
4785 ssh->kex_in_progress = TRUE;
4786
4787 /*
51470298 4788 * Construct and send our key exchange packet.
4789 */
ff3187f6 4790 s->pktout = ssh2_pkt_init(SSH2_MSG_KEXINIT);
51470298 4791 for (i = 0; i < 16; i++)
ff3187f6 4792 ssh2_pkt_addbyte(s->pktout, (unsigned char) random_byte());
51470298 4793 /* List key exchange algorithms. */
ff3187f6 4794 ssh2_pkt_addstring_start(s->pktout);
83e7d008 4795 commalist_started = 0;
4796 for (i = 0; i < s->n_preferred_kex; i++) {
4797 const struct ssh_kex *k = s->preferred_kex[i];
4798 if (!k) continue; /* warning flag */
4799 if (commalist_started)
ff3187f6 4800 ssh2_pkt_addstring_str(s->pktout, ",");
83e7d008 4801 ssh2_pkt_addstring_str(s->pktout, s->preferred_kex[i]->name);
4802 commalist_started = 1;
32874aea 4803 }
51470298 4804 /* List server host key algorithms. */
ff3187f6 4805 ssh2_pkt_addstring_start(s->pktout);
51470298 4806 for (i = 0; i < lenof(hostkey_algs); i++) {
ff3187f6 4807 ssh2_pkt_addstring_str(s->pktout, hostkey_algs[i]->name);
51470298 4808 if (i < lenof(hostkey_algs) - 1)
ff3187f6 4809 ssh2_pkt_addstring_str(s->pktout, ",");
32874aea 4810 }
51470298 4811 /* List client->server encryption algorithms. */
ff3187f6 4812 ssh2_pkt_addstring_start(s->pktout);
83e7d008 4813 commalist_started = 0;
51470298 4814 for (i = 0; i < s->n_preferred_ciphers; i++) {
4815 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4816 if (!c) continue; /* warning flag */
4817 for (j = 0; j < c->nciphers; j++) {
83e7d008 4818 if (commalist_started)
ff3187f6 4819 ssh2_pkt_addstring_str(s->pktout, ",");
4820 ssh2_pkt_addstring_str(s->pktout, c->list[j]->name);
83e7d008 4821 commalist_started = 1;
51470298 4822 }
4823 }
4824 /* List server->client encryption algorithms. */
ff3187f6 4825 ssh2_pkt_addstring_start(s->pktout);
83e7d008 4826 commalist_started = 0;
51470298 4827 for (i = 0; i < s->n_preferred_ciphers; i++) {
4828 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4829 if (!c) continue; /* warning flag */
4830 for (j = 0; j < c->nciphers; j++) {
83e7d008 4831 if (commalist_started)
ff3187f6 4832 ssh2_pkt_addstring_str(s->pktout, ",");
4833 ssh2_pkt_addstring_str(s->pktout, c->list[j]->name);
83e7d008 4834 commalist_started = 1;
51470298 4835 }
4836 }
4837 /* List client->server MAC algorithms. */
ff3187f6 4838 ssh2_pkt_addstring_start(s->pktout);
51470298 4839 for (i = 0; i < s->nmacs; i++) {
ff3187f6 4840 ssh2_pkt_addstring_str(s->pktout, s->maclist[i]->name);
51470298 4841 if (i < s->nmacs - 1)
ff3187f6 4842 ssh2_pkt_addstring_str(s->pktout, ",");
51470298 4843 }
4844 /* List server->client MAC algorithms. */
ff3187f6 4845 ssh2_pkt_addstring_start(s->pktout);
51470298 4846 for (i = 0; i < s->nmacs; i++) {
ff3187f6 4847 ssh2_pkt_addstring_str(s->pktout, s->maclist[i]->name);
51470298 4848 if (i < s->nmacs - 1)
ff3187f6 4849 ssh2_pkt_addstring_str(s->pktout, ",");
51470298 4850 }
4851 /* List client->server compression algorithms. */
ff3187f6 4852 ssh2_pkt_addstring_start(s->pktout);
f6e0abe2 4853 assert(lenof(compressions) > 1);
ff3187f6 4854 ssh2_pkt_addstring_str(s->pktout, s->preferred_comp->name);
f6e0abe2 4855 for (i = 0; i < lenof(compressions); i++) {
4856 const struct ssh_compress *c = compressions[i];
4857 if (c != s->preferred_comp) {
ff3187f6 4858 ssh2_pkt_addstring_str(s->pktout, ",");
4859 ssh2_pkt_addstring_str(s->pktout, c->name);
f6e0abe2 4860 }
51470298 4861 }
4862 /* List server->client compression algorithms. */
ff3187f6 4863 ssh2_pkt_addstring_start(s->pktout);
f6e0abe2 4864 assert(lenof(compressions) > 1);
ff3187f6 4865 ssh2_pkt_addstring_str(s->pktout, s->preferred_comp->name);
f6e0abe2 4866 for (i = 0; i < lenof(compressions); i++) {
4867 const struct ssh_compress *c = compressions[i];
4868 if (c != s->preferred_comp) {
ff3187f6 4869 ssh2_pkt_addstring_str(s->pktout, ",");
4870 ssh2_pkt_addstring_str(s->pktout, c->name);
f6e0abe2 4871 }
51470298 4872 }
4873 /* List client->server languages. Empty list. */
ff3187f6 4874 ssh2_pkt_addstring_start(s->pktout);
51470298 4875 /* List server->client languages. Empty list. */
ff3187f6 4876 ssh2_pkt_addstring_start(s->pktout);
51470298 4877 /* First KEX packet does _not_ follow, because we're not that brave. */
ff3187f6 4878 ssh2_pkt_addbool(s->pktout, FALSE);
51470298 4879 /* Reserved. */
ff3187f6 4880 ssh2_pkt_adduint32(s->pktout, 0);
e5574168 4881 }
0db56f73 4882
51470298 4883 ssh->exhash = ssh->exhashbase;
ff3187f6 4884 sha_string(&ssh->exhash, s->pktout->data + 5, s->pktout->length - 5);
0db56f73 4885
590f6a5f 4886 ssh2_pkt_send_noqueue(ssh, s->pktout);
e5574168 4887
ff3187f6 4888 if (!pktin)
4889 crWaitUntil(pktin);
4890 if (pktin->length > 5)
4891 sha_string(&ssh->exhash, pktin->data + 5, pktin->length - 5);
e5574168 4892
4893 /*
4894 * Now examine the other side's KEXINIT to see what we're up
4895 * to.
4896 */
51470298 4897 {
4898 char *str;
4899 int i, j, len;
4900
ff3187f6 4901 if (pktin->type != SSH2_MSG_KEXINIT) {
6b5cf8b4 4902 bombout(("expected key exchange packet from server"));
7ffdbc1a 4903 crStop(0);
32874aea 4904 }
51470298 4905 ssh->kex = NULL;
4906 ssh->hostkey = NULL;
4907 s->cscipher_tobe = NULL;
4908 s->sccipher_tobe = NULL;
4909 s->csmac_tobe = NULL;
4910 s->scmac_tobe = NULL;
4911 s->cscomp_tobe = NULL;
4912 s->sccomp_tobe = NULL;
ff3187f6 4913 pktin->savedpos += 16; /* skip garbage cookie */
4914 ssh_pkt_getstring(pktin, &str, &len); /* key exchange algorithms */
83e7d008 4915 s->warn = 0;
4916 for (i = 0; i < s->n_preferred_kex; i++) {
4917 const struct ssh_kex *k = s->preferred_kex[i];
4918 if (!k) {
4919 s->warn = 1;
4920 } else if (in_commasep_string(k->name, str, len)) {
4921 ssh->kex = k;
4922 }
4923 if (ssh->kex) {
bb348ab1 4924 if (s->warn) {
4925 sk_set_frozen(ssh->s, 1);
83e7d008 4926 askalg(ssh->frontend, "key-exchange algorithm",
4927 ssh->kex->name);
bb348ab1 4928 sk_set_frozen(ssh->s, 0);
4929 }
51470298 4930 break;
4931 }
32874aea 4932 }
83e7d008 4933 if (!ssh->kex) {
4934 bombout(("Couldn't agree a key exchange algorithm (available: %s)",
4935 str ? str : "(null)"));
4936 crStop(0);
4937 }
ff3187f6 4938 ssh_pkt_getstring(pktin, &str, &len); /* host key algorithms */
51470298 4939 for (i = 0; i < lenof(hostkey_algs); i++) {
4940 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
4941 ssh->hostkey = hostkey_algs[i];
4942 break;
4943 }
4944 }
ff3187f6 4945 ssh_pkt_getstring(pktin, &str, &len); /* client->server cipher */
51470298 4946 s->warn = 0;
4947 for (i = 0; i < s->n_preferred_ciphers; i++) {
4948 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4949 if (!c) {
4950 s->warn = 1;
4951 } else {
4952 for (j = 0; j < c->nciphers; j++) {
4953 if (in_commasep_string(c->list[j]->name, str, len)) {
4954 s->cscipher_tobe = c->list[j];
4955 break;
4956 }
ca20bfcf 4957 }
32874aea 4958 }
51470298 4959 if (s->cscipher_tobe) {
bb348ab1 4960 if (s->warn) {
4961 sk_set_frozen(ssh->s, 1);
83e7d008 4962 askalg(ssh->frontend, "client-to-server cipher",
4963 s->cscipher_tobe->name);
bb348ab1 4964 sk_set_frozen(ssh->s, 0);
4965 }
51470298 4966 break;
4967 }
32874aea 4968 }
51470298 4969 if (!s->cscipher_tobe) {
6b5cf8b4 4970 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
57356d63 4971 str ? str : "(null)"));
7ffdbc1a 4972 crStop(0);
ca20bfcf 4973 }
0ef8f407 4974
ff3187f6 4975 ssh_pkt_getstring(pktin, &str, &len); /* server->client cipher */
51470298 4976 s->warn = 0;
4977 for (i = 0; i < s->n_preferred_ciphers; i++) {
4978 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4979 if (!c) {
4980 s->warn = 1;
4981 } else {
4982 for (j = 0; j < c->nciphers; j++) {
4983 if (in_commasep_string(c->list[j]->name, str, len)) {
4984 s->sccipher_tobe = c->list[j];
4985 break;
4986 }
ca20bfcf 4987 }
32874aea 4988 }
51470298 4989 if (s->sccipher_tobe) {
bb348ab1 4990 if (s->warn) {
4991 sk_set_frozen(ssh->s, 1);
83e7d008 4992 askalg(ssh->frontend, "server-to-client cipher",
4993 s->sccipher_tobe->name);
bb348ab1 4994 sk_set_frozen(ssh->s, 0);
4995 }
51470298 4996 break;
4997 }
32874aea 4998 }
51470298 4999 if (!s->sccipher_tobe) {
6b5cf8b4 5000 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
57356d63 5001 str ? str : "(null)"));
7ffdbc1a 5002 crStop(0);
ca20bfcf 5003 }
0ef8f407 5004
ff3187f6 5005 ssh_pkt_getstring(pktin, &str, &len); /* client->server mac */
51470298 5006 for (i = 0; i < s->nmacs; i++) {
5007 if (in_commasep_string(s->maclist[i]->name, str, len)) {
5008 s->csmac_tobe = s->maclist[i];
5009 break;
5010 }
32874aea 5011 }
ff3187f6 5012 ssh_pkt_getstring(pktin, &str, &len); /* server->client mac */
51470298 5013 for (i = 0; i < s->nmacs; i++) {
5014 if (in_commasep_string(s->maclist[i]->name, str, len)) {
5015 s->scmac_tobe = s->maclist[i];
5016 break;
5017 }
32874aea 5018 }
ff3187f6 5019 ssh_pkt_getstring(pktin, &str, &len); /* client->server compression */
51470298 5020 for (i = 0; i < lenof(compressions) + 1; i++) {
5021 const struct ssh_compress *c =
5022 i == 0 ? s->preferred_comp : compressions[i - 1];
5023 if (in_commasep_string(c->name, str, len)) {
5024 s->cscomp_tobe = c;
5025 break;
5026 }
32874aea 5027 }
ff3187f6 5028 ssh_pkt_getstring(pktin, &str, &len); /* server->client compression */
51470298 5029 for (i = 0; i < lenof(compressions) + 1; i++) {
5030 const struct ssh_compress *c =
5031 i == 0 ? s->preferred_comp : compressions[i - 1];
5032 if (in_commasep_string(c->name, str, len)) {
5033 s->sccomp_tobe = c;
5034 break;
5035 }
32874aea 5036 }
e5574168 5037 }
e5574168 5038
5039 /*
7bd5a860 5040 * Work out the number of bits of key we will need from the key
5041 * exchange. We start with the maximum key length of either
5042 * cipher...
5043 */
5044 {
32874aea 5045 int csbits, scbits;
7bd5a860 5046
51470298 5047 csbits = s->cscipher_tobe->keylen;
5048 scbits = s->sccipher_tobe->keylen;
5049 s->nbits = (csbits > scbits ? csbits : scbits);
7bd5a860 5050 }
5051 /* The keys only have 160-bit entropy, since they're based on
5052 * a SHA-1 hash. So cap the key size at 160 bits. */
51470298 5053 if (s->nbits > 160)
5054 s->nbits = 160;
7bd5a860 5055
5056 /*
a92dd380 5057 * If we're doing Diffie-Hellman group exchange, start by
5058 * requesting a group.
e5574168 5059 */
d1aaf71d 5060 if (!ssh->kex->pdata) {
32874aea 5061 logevent("Doing Diffie-Hellman group exchange");
51470298 5062 ssh->pkt_ctx |= SSH2_PKTCTX_DHGEX;
32874aea 5063 /*
5064 * Work out how big a DH group we will need to allow that
5065 * much data.
7bd5a860 5066 */
51470298 5067 s->pbits = 512 << ((s->nbits - 1) / 64);
ff3187f6 5068 s->pktout = ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST);
5069 ssh2_pkt_adduint32(s->pktout, s->pbits);
590f6a5f 5070 ssh2_pkt_send_noqueue(ssh, s->pktout);
32874aea 5071
ff3187f6 5072 crWaitUntil(pktin);
5073 if (pktin->type != SSH2_MSG_KEX_DH_GEX_GROUP) {
6b5cf8b4 5074 bombout(("expected key exchange group packet from server"));
7ffdbc1a 5075 crStop(0);
32874aea 5076 }
ff3187f6 5077 s->p = ssh2_pkt_getmp(pktin);
5078 s->g = ssh2_pkt_getmp(pktin);
5079 if (!s->p || !s->g) {
5080 bombout(("unable to read mp-ints from incoming group packet"));
5081 crStop(0);
5082 }
d1aaf71d 5083 ssh->kex_ctx = dh_setup_gex(s->p, s->g);
51470298 5084 s->kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
5085 s->kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY;
a92dd380 5086 } else {
d1aaf71d 5087 ssh->pkt_ctx |= SSH2_PKTCTX_DHGROUP;
5088 ssh->kex_ctx = dh_setup_group(ssh->kex);
51470298 5089 s->kex_init_value = SSH2_MSG_KEXDH_INIT;
5090 s->kex_reply_value = SSH2_MSG_KEXDH_REPLY;
d1aaf71d 5091 logeventf(ssh, "Using Diffie-Hellman with standard group \"%s\"",
5092 ssh->kex->groupname);
8d5de777 5093 }
e5574168 5094
a92dd380 5095 logevent("Doing Diffie-Hellman key exchange");
e5574168 5096 /*
a92dd380 5097 * Now generate and send e for Diffie-Hellman.
e5574168 5098 */
27cd7fc2 5099 s->e = dh_create_e(ssh->kex_ctx, s->nbits * 2);
ff3187f6 5100 s->pktout = ssh2_pkt_init(s->kex_init_value);
5101 ssh2_pkt_addmp(s->pktout, s->e);
590f6a5f 5102 ssh2_pkt_send_noqueue(ssh, s->pktout);
e5574168 5103
ff3187f6 5104 crWaitUntil(pktin);
5105 if (pktin->type != s->kex_reply_value) {
6b5cf8b4 5106 bombout(("expected key exchange reply packet from server"));
7ffdbc1a 5107 crStop(0);
7cca0d81 5108 }
ff3187f6 5109 ssh_pkt_getstring(pktin, &s->hostkeydata, &s->hostkeylen);
5110 s->f = ssh2_pkt_getmp(pktin);
5111 if (!s->f) {
5112 bombout(("unable to parse key exchange reply packet"));
5113 crStop(0);
5114 }
5115 ssh_pkt_getstring(pktin, &s->sigdata, &s->siglen);
e5574168 5116
27cd7fc2 5117 s->K = dh_find_K(ssh->kex_ctx, s->f);
e5574168 5118
51470298 5119 sha_string(&ssh->exhash, s->hostkeydata, s->hostkeylen);
5120 if (ssh->kex == &ssh_diffiehellman_gex) {
5121 sha_uint32(&ssh->exhash, s->pbits);
5122 sha_mpint(&ssh->exhash, s->p);
5123 sha_mpint(&ssh->exhash, s->g);
a92dd380 5124 }
51470298 5125 sha_mpint(&ssh->exhash, s->e);
5126 sha_mpint(&ssh->exhash, s->f);
5127 sha_mpint(&ssh->exhash, s->K);
5128 SHA_Final(&ssh->exhash, s->exchange_hash);
e5574168 5129
27cd7fc2 5130 dh_cleanup(ssh->kex_ctx);
fabd1805 5131 ssh->kex_ctx = NULL;
3709bfe9 5132
7cca0d81 5133#if 0
765c4200 5134 debug(("Exchange hash is:\n"));
51470298 5135 dmemdump(s->exchange_hash, 20);
7cca0d81 5136#endif
5137
51470298 5138 s->hkey = ssh->hostkey->newkey(s->hostkeydata, s->hostkeylen);
5139 if (!s->hkey ||
5140 !ssh->hostkey->verifysig(s->hkey, s->sigdata, s->siglen,
d8baa528 5141 (char *)s->exchange_hash, 20)) {
6b5cf8b4 5142 bombout(("Server's host key did not match the signature supplied"));
7ffdbc1a 5143 crStop(0);
8d5de777 5144 }
e5574168 5145
5146 /*
7cca0d81 5147 * Authenticate remote host: verify host key. (We've already
5148 * checked the signature of the exchange hash.)
e5574168 5149 */
51470298 5150 s->keystr = ssh->hostkey->fmtkey(s->hkey);
5151 s->fingerprint = ssh->hostkey->fingerprint(s->hkey);
bb348ab1 5152 sk_set_frozen(ssh->s, 1);
a8327734 5153 verify_ssh_host_key(ssh->frontend,
5154 ssh->savedhost, ssh->savedport, ssh->hostkey->keytype,
51470298 5155 s->keystr, s->fingerprint);
bb348ab1 5156 sk_set_frozen(ssh->s, 0);
e13bba36 5157 if (!s->got_session_id) { /* don't bother logging this in rekeys */
5e0d7cb8 5158 logevent("Host key fingerprint is:");
51470298 5159 logevent(s->fingerprint);
5e0d7cb8 5160 }
51470298 5161 sfree(s->fingerprint);
5162 sfree(s->keystr);
5163 ssh->hostkey->freekey(s->hkey);
d39f364a 5164
5165 /*
9442dd57 5166 * The exchange hash from the very first key exchange is also
5167 * the session id, used in session key construction and
5168 * authentication.
5169 */
e13bba36 5170 if (!s->got_session_id) {
9442dd57 5171 memcpy(ssh->v2_session_id, s->exchange_hash,
5172 sizeof(s->exchange_hash));
e13bba36 5173 s->got_session_id = TRUE;
5174 }
9442dd57 5175
5176 /*
7cca0d81 5177 * Send SSH2_MSG_NEWKEYS.
d39f364a 5178 */
ff3187f6 5179 s->pktout = ssh2_pkt_init(SSH2_MSG_NEWKEYS);
590f6a5f 5180 ssh2_pkt_send_noqueue(ssh, s->pktout);
9442dd57 5181 ssh->outgoing_data_size = 0; /* start counting from here */
5182
5183 /*
5184 * We've sent client NEWKEYS, so create and initialise
c64fe7d4 5185 * client-to-server session keys.
9442dd57 5186 */
5187 if (ssh->cs_cipher_ctx)
5188 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
5189 ssh->cscipher = s->cscipher_tobe;
5190 ssh->cs_cipher_ctx = ssh->cscipher->make_context();
5191
5192 if (ssh->cs_mac_ctx)
5193 ssh->csmac->free_context(ssh->cs_mac_ctx);
5194 ssh->csmac = s->csmac_tobe;
5195 ssh->cs_mac_ctx = ssh->csmac->make_context();
5196
5197 if (ssh->cs_comp_ctx)
5198 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
5199 ssh->cscomp = s->cscomp_tobe;
5200 ssh->cs_comp_ctx = ssh->cscomp->compress_init();
5201
5202 /*
5203 * Set IVs on client-to-server keys. Here we use the exchange
5204 * hash from the _first_ key exchange.
5205 */
5206 {
5207 unsigned char keyspace[40];
5208 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'C',keyspace);
5209 ssh->cscipher->setkey(ssh->cs_cipher_ctx, keyspace);
5210 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'A',keyspace);
5211 ssh->cscipher->setiv(ssh->cs_cipher_ctx, keyspace);
5212 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'E',keyspace);
5213 ssh->csmac->setkey(ssh->cs_mac_ctx, keyspace);
5214 }
5215
5216 logeventf(ssh, "Initialised %.200s client->server encryption",
5217 ssh->cscipher->text_name);
5218 logeventf(ssh, "Initialised %.200s client->server MAC algorithm",
5219 ssh->csmac->text_name);
5220 if (ssh->cscomp->text_name)
5221 logeventf(ssh, "Initialised %s compression",
5222 ssh->cscomp->text_name);
590f6a5f 5223
5224 /*
5225 * Now our end of the key exchange is complete, we can send all
5226 * our queued higher-layer packets.
5227 */
5228 ssh->queueing = FALSE;
5229 ssh2_pkt_queuesend(ssh);
d39f364a 5230
5231 /*
8406eaf9 5232 * Expect SSH2_MSG_NEWKEYS from server.
5233 */
ff3187f6 5234 crWaitUntil(pktin);
5235 if (pktin->type != SSH2_MSG_NEWKEYS) {
6b5cf8b4 5236 bombout(("expected new-keys packet from server"));
7ffdbc1a 5237 crStop(0);
8406eaf9 5238 }
9442dd57 5239 ssh->incoming_data_size = 0; /* start counting from here */
8406eaf9 5240
5241 /*
9442dd57 5242 * We've seen server NEWKEYS, so create and initialise
5243 * server-to-client session keys.
d39f364a 5244 */
371e569c 5245 if (ssh->sc_cipher_ctx)
5246 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
51470298 5247 ssh->sccipher = s->sccipher_tobe;
371e569c 5248 ssh->sc_cipher_ctx = ssh->sccipher->make_context();
e0e1a00d 5249
e0e1a00d 5250 if (ssh->sc_mac_ctx)
5251 ssh->scmac->free_context(ssh->sc_mac_ctx);
51470298 5252 ssh->scmac = s->scmac_tobe;
e0e1a00d 5253 ssh->sc_mac_ctx = ssh->scmac->make_context();
5254
5366aed8 5255 if (ssh->sc_comp_ctx)
5256 ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
51470298 5257 ssh->sccomp = s->sccomp_tobe;
5366aed8 5258 ssh->sc_comp_ctx = ssh->sccomp->decompress_init();
5259
d39f364a 5260 /*
9442dd57 5261 * Set IVs on server-to-client keys. Here we use the exchange
5262 * hash from the _first_ key exchange.
d39f364a 5263 */
51470298 5264 {
5265 unsigned char keyspace[40];
51470298 5266 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'D',keyspace);
371e569c 5267 ssh->sccipher->setkey(ssh->sc_cipher_ctx, keyspace);
51470298 5268 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'B',keyspace);
371e569c 5269 ssh->sccipher->setiv(ssh->sc_cipher_ctx, keyspace);
51470298 5270 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'F',keyspace);
e0e1a00d 5271 ssh->scmac->setkey(ssh->sc_mac_ctx, keyspace);
51470298 5272 }
57356d63 5273 logeventf(ssh, "Initialised %.200s server->client encryption",
5274 ssh->sccipher->text_name);
6c135243 5275 logeventf(ssh, "Initialised %.200s server->client MAC algorithm",
5276 ssh->scmac->text_name);
57356d63 5277 if (ssh->sccomp->text_name)
5278 logeventf(ssh, "Initialised %s decompression",
5279 ssh->sccomp->text_name);
9442dd57 5280
5281 /*
5282 * Free key exchange data.
5283 */
679539d7 5284 freebn(s->f);
679539d7 5285 freebn(s->K);
b3949e7e 5286 if (ssh->kex == &ssh_diffiehellman_gex) {
5287 freebn(s->g);
5288 freebn(s->p);
5289 }
d39f364a 5290
033b4cef 5291 /*
e13bba36 5292 * Key exchange is over. Loop straight back round if we have a
5293 * deferred rekey reason.
5294 */
5295 if (ssh->deferred_rekey_reason) {
5296 logevent(ssh->deferred_rekey_reason);
5297 pktin = NULL;
5298 ssh->deferred_rekey_reason = NULL;
5299 goto begin_key_exchange;
5300 }
5301
5302 /*
5303 * Otherwise, schedule a timer for our next rekey.
9442dd57 5304 */
5305 ssh->kex_in_progress = FALSE;
e6c1536e 5306 ssh->last_rekey = GETTICKCOUNT();
d57f70af 5307 if (ssh->cfg.ssh_rekey_time != 0)
5308 ssh->next_rekey = schedule_timer(ssh->cfg.ssh_rekey_time*60*TICKSPERSEC,
5309 ssh2_timer, ssh);
e13bba36 5310
9442dd57 5311 /*
0db56f73 5312 * If this is the first key exchange phase, we must pass the
5313 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
5314 * wants to see it but because it will need time to initialise
5315 * itself before it sees an actual packet. In subsequent key
5316 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
5317 * it would only confuse the layer above.
5318 */
e13bba36 5319 if (s->activated_authconn) {
b09eaa88 5320 crReturn(1);
0db56f73 5321 }
e13bba36 5322 s->activated_authconn = TRUE;
0db56f73 5323
5324 /*
7cca0d81 5325 * Now we're encrypting. Begin returning 1 to the protocol main
5326 * function so that other things can run on top of the
5327 * transport. If we ever see a KEXINIT, we must go back to the
5328 * start.
9442dd57 5329 *
5330 * We _also_ go back to the start if we see pktin==NULL and
5331 * inlen==-1, because this is a special signal meaning
5332 * `initiate client-driven rekey', and `in' contains a message
5333 * giving the reason for the rekey.
033b4cef 5334 */
9442dd57 5335 while (!((pktin && pktin->type == SSH2_MSG_KEXINIT) ||
5336 (!pktin && inlen == -1))) {
f382c87d 5337 wait_for_rekey:
32874aea 5338 crReturn(1);
e96adf72 5339 }
9442dd57 5340 if (pktin) {
5341 logevent("Server initiated key re-exchange");
5342 } else {
f382c87d 5343 /*
5344 * Special case: if the server bug is set that doesn't
5345 * allow rekeying, we give a different log message and
5346 * continue waiting. (If such a server _initiates_ a rekey,
5347 * we process it anyway!)
5348 */
5349 if ((ssh->remote_bugs & BUG_SSH2_REKEY)) {
5350 logeventf(ssh, "Server bug prevents key re-exchange (%s)",
5351 (char *)in);
5352 /* Reset the counters, so that at least this message doesn't
5353 * hit the event log _too_ often. */
5354 ssh->outgoing_data_size = 0;
5355 ssh->incoming_data_size = 0;
5356 if (ssh->cfg.ssh_rekey_time != 0) {
5357 ssh->next_rekey =
5358 schedule_timer(ssh->cfg.ssh_rekey_time*60*TICKSPERSEC,
5359 ssh2_timer, ssh);
5360 }
5361 goto wait_for_rekey; /* this is utterly horrid */
5362 } else {
5363 logeventf(ssh, "Initiating key re-exchange (%s)", (char *)in);
f382c87d 5364 }
9442dd57 5365 }
7cca0d81 5366 goto begin_key_exchange;
e5574168 5367
5368 crFinish(1);
5369}
5370
7cca0d81 5371/*
783415f8 5372 * Add data to an SSH2 channel output buffer.
5373 */
32874aea 5374static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
5375 int len)
5376{
5471d09a 5377 bufchain_add(&c->v.v2.outbuffer, buf, len);
783415f8 5378}
5379
5380/*
5381 * Attempt to send data on an SSH2 channel.
5382 */
5471d09a 5383static int ssh2_try_send(struct ssh_channel *c)
32874aea 5384{
51470298 5385 Ssh ssh = c->ssh;
ff3187f6 5386 struct Packet *pktout;
51470298 5387
5471d09a 5388 while (c->v.v2.remwindow > 0 && bufchain_size(&c->v.v2.outbuffer) > 0) {
5389 int len;
5390 void *data;
5391 bufchain_prefix(&c->v.v2.outbuffer, &data, &len);
5392 if ((unsigned)len > c->v.v2.remwindow)
5393 len = c->v.v2.remwindow;
5394 if ((unsigned)len > c->v.v2.remmaxpkt)
5395 len = c->v.v2.remmaxpkt;
ff3187f6 5396 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
5397 ssh2_pkt_adduint32(pktout, c->remoteid);
5398 dont_log_data(ssh, pktout, PKTLOG_OMIT);
5399 ssh2_pkt_addstring_start(pktout);
5400 ssh2_pkt_addstring_data(pktout, data, len);
5401 end_log_omission(ssh, pktout);
5402 ssh2_pkt_send(ssh, pktout);
5471d09a 5403 bufchain_consume(&c->v.v2.outbuffer, len);
5404 c->v.v2.remwindow -= len;
5405 }
5406
5407 /*
5408 * After having sent as much data as we can, return the amount
5409 * still buffered.
5410 */
5411 return bufchain_size(&c->v.v2.outbuffer);
5412}
5413
5414/*
5415 * Potentially enlarge the window on an SSH2 channel.
5416 */
5417static void ssh2_set_window(struct ssh_channel *c, unsigned newwin)
5418{
51470298 5419 Ssh ssh = c->ssh;
5420
6b69f42e 5421 /*
5422 * Never send WINDOW_ADJUST for a channel that the remote side
5423 * already thinks it's closed; there's no point, since it won't
5424 * be sending any more data anyway.
5425 */
5426 if (c->closes != 0)
5427 return;
5428
5471d09a 5429 if (newwin > c->v.v2.locwindow) {
ff3187f6 5430 struct Packet *pktout;
5431
5432 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
5433 ssh2_pkt_adduint32(pktout, c->remoteid);
5434 ssh2_pkt_adduint32(pktout, newwin - c->v.v2.locwindow);
5435 ssh2_pkt_send(ssh, pktout);
5471d09a 5436 c->v.v2.locwindow = newwin;
783415f8 5437 }
5438}
5439
51df0ab5 5440static void ssh2_msg_channel_window_adjust(Ssh ssh, struct Packet *pktin)
b09eaa88 5441{
5442 unsigned i = ssh_pkt_getuint32(pktin);
5443 struct ssh_channel *c;
5444 c = find234(ssh->channels, &i, ssh_channelfind);
5445 if (c && !c->closes)
5446 c->v.v2.remwindow += ssh_pkt_getuint32(pktin);
5447}
5448
51df0ab5 5449static void ssh2_msg_channel_data(Ssh ssh, struct Packet *pktin)
5450{
5451 char *data;
aa63ab7e 5452 unsigned int length;
51df0ab5 5453 unsigned i = ssh_pkt_getuint32(pktin);
5454 struct ssh_channel *c;
5455 c = find234(ssh->channels, &i, ssh_channelfind);
5456 if (!c)
5457 return; /* nonexistent channel */
5458 if (pktin->type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
5459 ssh_pkt_getuint32(pktin) != SSH2_EXTENDED_DATA_STDERR)
5460 return; /* extended but not stderr */
5461 ssh_pkt_getstring(pktin, &data, &length);
5462 if (data) {
5463 int bufsize = 0;
5464 c->v.v2.locwindow -= length;
5465 switch (c->type) {
5466 case CHAN_MAINSESSION:
5467 bufsize =
5468 from_backend(ssh->frontend, pktin->type ==
5469 SSH2_MSG_CHANNEL_EXTENDED_DATA,
5470 data, length);
5471 break;
5472 case CHAN_X11:
5473 bufsize = x11_send(c->u.x11.s, data, length);
5474 break;
5475 case CHAN_SOCKDATA:
5476 bufsize = pfd_send(c->u.pfd.s, data, length);
5477 break;
5478 case CHAN_AGENT:
5479 while (length > 0) {
5480 if (c->u.a.lensofar < 4) {
aa63ab7e 5481 unsigned int l = min(4 - c->u.a.lensofar, length);
51df0ab5 5482 memcpy(c->u.a.msglen + c->u.a.lensofar,
5483 data, l);
5484 data += l;
5485 length -= l;
5486 c->u.a.lensofar += l;
5487 }
5488 if (c->u.a.lensofar == 4) {
5489 c->u.a.totallen =
5490 4 + GET_32BIT(c->u.a.msglen);
5491 c->u.a.message = snewn(c->u.a.totallen,
5492 unsigned char);
5493 memcpy(c->u.a.message, c->u.a.msglen, 4);
5494 }
5495 if (c->u.a.lensofar >= 4 && length > 0) {
aa63ab7e 5496 unsigned int l =
51df0ab5 5497 min(c->u.a.totallen - c->u.a.lensofar,
5498 length);
5499 memcpy(c->u.a.message + c->u.a.lensofar,
5500 data, l);
5501 data += l;
5502 length -= l;
5503 c->u.a.lensofar += l;
5504 }
5505 if (c->u.a.lensofar == c->u.a.totallen) {
5506 void *reply;
5507 int replylen;
5508 if (agent_query(c->u.a.message,
5509 c->u.a.totallen,
5510 &reply, &replylen,
5511 ssh_agentf_callback, c))
5512 ssh_agentf_callback(c, reply, replylen);
5513 sfree(c->u.a.message);
5514 c->u.a.lensofar = 0;
5515 }
5516 }
5517 bufsize = 0;
5518 break;
5519 }
5520 /*
5521 * If we are not buffering too much data,
5522 * enlarge the window again at the remote side.
5523 */
5524 if (bufsize < OUR_V2_WINSIZE)
5525 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
5526 }
5527}
5528
5529static void ssh2_msg_channel_eof(Ssh ssh, struct Packet *pktin)
5530{
5531 unsigned i = ssh_pkt_getuint32(pktin);
5532 struct ssh_channel *c;
5533
5534 c = find234(ssh->channels, &i, ssh_channelfind);
5535 if (!c)
5536 return; /* nonexistent channel */
5537
5538 if (c->type == CHAN_X11) {
5539 /*
5540 * Remote EOF on an X11 channel means we should
5541 * wrap up and close the channel ourselves.
5542 */
5543 x11_close(c->u.x11.s);
5544 sshfwd_close(c);
5545 } else if (c->type == CHAN_AGENT) {
5546 sshfwd_close(c);
5547 } else if (c->type == CHAN_SOCKDATA) {
5548 pfd_close(c->u.pfd.s);
5549 sshfwd_close(c);
5550 }
5551}
5552
5553static void ssh2_msg_channel_close(Ssh ssh, struct Packet *pktin)
5554{
5555 unsigned i = ssh_pkt_getuint32(pktin);
5556 struct ssh_channel *c;
5557 struct Packet *pktout;
5558
5559 c = find234(ssh->channels, &i, ssh_channelfind);
5560 if (!c || ((int)c->remoteid) == -1) {
5561 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
5562 c ? "half-open" : "nonexistent", i));
5563 return;
5564 }
5565 /* Do pre-close processing on the channel. */
5566 switch (c->type) {
5567 case CHAN_MAINSESSION:
5568 ssh->mainchan = NULL;
5569 update_specials_menu(ssh->frontend);
5570 break;
5571 case CHAN_X11:
5572 if (c->u.x11.s != NULL)
5573 x11_close(c->u.x11.s);
5574 sshfwd_close(c);
5575 break;
5576 case CHAN_AGENT:
5577 sshfwd_close(c);
5578 break;
5579 case CHAN_SOCKDATA:
5580 if (c->u.pfd.s != NULL)
5581 pfd_close(c->u.pfd.s);
5582 sshfwd_close(c);
5583 break;
5584 }
5585 if (c->closes == 0) {
5586 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
5587 ssh2_pkt_adduint32(pktout, c->remoteid);
5588 ssh2_pkt_send(ssh, pktout);
5589 }
5590 del234(ssh->channels, c);
5591 bufchain_clear(&c->v.v2.outbuffer);
5592 sfree(c);
5593
5594 /*
5595 * See if that was the last channel left open.
5596 * (This is only our termination condition if we're
5597 * not running in -N mode.)
5598 */
5599 if (!ssh->cfg.ssh_no_shell && count234(ssh->channels) == 0) {
5600 logevent("All channels closed. Disconnecting");
5601#if 0
5602 /*
5603 * We used to send SSH_MSG_DISCONNECT here,
5604 * because I'd believed that _every_ conforming
5605 * SSH2 connection had to end with a disconnect
5606 * being sent by at least one side; apparently
5607 * I was wrong and it's perfectly OK to
5608 * unceremoniously slam the connection shut
5609 * when you're done, and indeed OpenSSH feels
5610 * this is more polite than sending a
5611 * DISCONNECT. So now we don't.
5612 */
5613 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
5614 ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
5615 ssh2_pkt_addstring(s->pktout, "All open channels closed");
5616 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
5617 ssh2_pkt_send_noqueue(ssh, s->pktout);
5618#endif
ac934965 5619 ssh->close_expected = TRUE;
51df0ab5 5620 ssh_closing((Plug)ssh, NULL, 0, 0);
5621 }
5622}
5623
5624static void ssh2_msg_channel_open_confirmation(Ssh ssh, struct Packet *pktin)
5625{
5626 unsigned i = ssh_pkt_getuint32(pktin);
5627 struct ssh_channel *c;
5628 struct Packet *pktout;
5629
5630 c = find234(ssh->channels, &i, ssh_channelfind);
5631 if (!c)
5632 return; /* nonexistent channel */
5633 if (c->type != CHAN_SOCKDATA_DORMANT)
5634 return; /* dunno why they're confirming this */
5635 c->remoteid = ssh_pkt_getuint32(pktin);
5636 c->type = CHAN_SOCKDATA;
5637 c->v.v2.remwindow = ssh_pkt_getuint32(pktin);
5638 c->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin);
5639 if (c->u.pfd.s)
5640 pfd_confirm(c->u.pfd.s);
5641 if (c->closes) {
5642 /*
5643 * We have a pending close on this channel,
5644 * which we decided on before the server acked
5645 * the channel open. So now we know the
5646 * remoteid, we can close it again.
5647 */
5648 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
5649 ssh2_pkt_adduint32(pktout, c->remoteid);
5650 ssh2_pkt_send(ssh, pktout);
5651 }
5652}
5653
5654static void ssh2_msg_channel_open_failure(Ssh ssh, struct Packet *pktin)
5655{
5656 static const char *const reasons[] = {
5657 "<unknown reason code>",
5658 "Administratively prohibited",
5659 "Connect failed",
5660 "Unknown channel type",
5661 "Resource shortage",
5662 };
5663 unsigned i = ssh_pkt_getuint32(pktin);
5664 unsigned reason_code;
5665 char *reason_string;
5666 int reason_length;
5667 char *message;
5668 struct ssh_channel *c;
5669 c = find234(ssh->channels, &i, ssh_channelfind);
5670 if (!c)
5671 return; /* nonexistent channel */
5672 if (c->type != CHAN_SOCKDATA_DORMANT)
5673 return; /* dunno why they're failing this */
5674
5675 reason_code = ssh_pkt_getuint32(pktin);
5676 if (reason_code >= lenof(reasons))
5677 reason_code = 0; /* ensure reasons[reason_code] in range */
5678 ssh_pkt_getstring(pktin, &reason_string, &reason_length);
5679 message = dupprintf("Forwarded connection refused by"
5680 " server: %s [%.*s]", reasons[reason_code],
5681 reason_length, reason_string);
5682 logevent(message);
5683 sfree(message);
5684
5685 pfd_close(c->u.pfd.s);
5686
5687 del234(ssh->channels, c);
5688 sfree(c);
5689}
5690
5691static void ssh2_msg_channel_request(Ssh ssh, struct Packet *pktin)
5692{
5693 unsigned localid;
5694 char *type;
5695 int typelen, want_reply;
5696 int reply = SSH2_MSG_CHANNEL_FAILURE; /* default */
5697 struct ssh_channel *c;
5698 struct Packet *pktout;
5699
5700 localid = ssh_pkt_getuint32(pktin);
5701 ssh_pkt_getstring(pktin, &type, &typelen);
5702 want_reply = ssh2_pkt_getbool(pktin);
5703
5704 /*
5705 * First, check that the channel exists. Otherwise,
5706 * we can instantly disconnect with a rude message.
5707 */
5708 c = find234(ssh->channels, &localid, ssh_channelfind);
5709 if (!c) {
5710 char buf[80];
5711 sprintf(buf, "Received channel request for nonexistent"
5712 " channel %d", localid);
5713 logevent(buf);
5714 pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
5715 ssh2_pkt_adduint32(pktout, SSH2_DISCONNECT_BY_APPLICATION);
5716 ssh2_pkt_addstring(pktout, buf);
5717 ssh2_pkt_addstring(pktout, "en"); /* language tag */
5718 ssh2_pkt_send_noqueue(ssh, pktout);
5719 connection_fatal(ssh->frontend, "%s", buf);
ac934965 5720 ssh->close_expected = TRUE;
51df0ab5 5721 ssh_closing((Plug)ssh, NULL, 0, 0);
5722 return;
5723 }
5724
5725 /*
5726 * Having got the channel number, we now look at
5727 * the request type string to see if it's something
5728 * we recognise.
5729 */
5730 if (c == ssh->mainchan) {
5731 /*
5732 * We recognise "exit-status" and "exit-signal" on
5733 * the primary channel.
5734 */
5735 if (typelen == 11 &&
5736 !memcmp(type, "exit-status", 11)) {
5737
5738 ssh->exitcode = ssh_pkt_getuint32(pktin);
5739 logeventf(ssh, "Server sent command exit status %d",
5740 ssh->exitcode);
5741 reply = SSH2_MSG_CHANNEL_SUCCESS;
5742
5743 } else if (typelen == 11 &&
5744 !memcmp(type, "exit-signal", 11)) {
5745
5746 int is_plausible = TRUE, is_int = FALSE;
5747 char *fmt_sig = "", *fmt_msg = "";
5748 char *msg;
5749 int msglen = 0, core = FALSE;
5750 /* ICK: older versions of OpenSSH (e.g. 3.4p1)
5751 * provide an `int' for the signal, despite its
5752 * having been a `string' in the drafts since at
5753 * least 2001. (Fixed in session.c 1.147.) Try to
5754 * infer which we can safely parse it as. */
5755 {
5756 unsigned char *p = pktin->body +
5757 pktin->savedpos;
5758 long len = pktin->length - pktin->savedpos;
5759 unsigned long num = GET_32BIT(p); /* what is it? */
5760 /* If it's 0, it hardly matters; assume string */
5761 if (num == 0) {
5762 is_int = FALSE;
5763 } else {
5764 int maybe_int = FALSE, maybe_str = FALSE;
5765#define CHECK_HYPOTHESIS(offset, result) \
5766 do { \
5767 long q = offset; \
5768 if (q >= 0 && q+4 <= len) { \
5769 q = q + 4 + GET_32BIT(p+q); \
5770 if (q >= 0 && q+4 <= len && \
5771 (q = q + 4 + GET_32BIT(p+q)) && q == len) \
5772 result = TRUE; \
5773 } \
5774 } while(0)
5775 CHECK_HYPOTHESIS(4+1, maybe_int);
5776 CHECK_HYPOTHESIS(4+num+1, maybe_str);
5777#undef CHECK_HYPOTHESIS
5778 if (maybe_int && !maybe_str)
5779 is_int = TRUE;
5780 else if (!maybe_int && maybe_str)
5781 is_int = FALSE;
5782 else
5783 /* Crikey. Either or neither. Panic. */
5784 is_plausible = FALSE;
5785 }
5786 }
5787 if (is_plausible) {
5788 if (is_int) {
5789 /* Old non-standard OpenSSH. */
5790 int signum = ssh_pkt_getuint32(pktin);
5791 fmt_sig = dupprintf(" %d", signum);
5792 } else {
5793 /* As per the drafts. */
5794 char *sig;
5795 int siglen;
5796 ssh_pkt_getstring(pktin, &sig, &siglen);
5797 /* Signal name isn't supposed to be blank, but
5798 * let's cope gracefully if it is. */
5799 if (siglen) {
5800 fmt_sig = dupprintf(" \"%.*s\"",
5801 siglen, sig);
5802 }
5803 }
5804 core = ssh2_pkt_getbool(pktin);
5805 ssh_pkt_getstring(pktin, &msg, &msglen);
5806 if (msglen) {
5807 fmt_msg = dupprintf(" (\"%.*s\")", msglen, msg);
5808 }
5809 /* ignore lang tag */
5810 } /* else don't attempt to parse */
5811 logeventf(ssh, "Server exited on signal%s%s%s",
5812 fmt_sig, core ? " (core dumped)" : "",
5813 fmt_msg);
5814 if (*fmt_sig) sfree(fmt_sig);
5815 if (*fmt_msg) sfree(fmt_msg);
5816 reply = SSH2_MSG_CHANNEL_SUCCESS;
5817
5818 }
5819 } else {
5820 /*
5821 * This is a channel request we don't know
5822 * about, so we now either ignore the request
5823 * or respond with CHANNEL_FAILURE, depending
5824 * on want_reply.
5825 */
5826 reply = SSH2_MSG_CHANNEL_FAILURE;
5827 }
5828 if (want_reply) {
5829 pktout = ssh2_pkt_init(reply);
5830 ssh2_pkt_adduint32(pktout, c->remoteid);
5831 ssh2_pkt_send(ssh, pktout);
5832 }
5833}
5834
5835static void ssh2_msg_global_request(Ssh ssh, struct Packet *pktin)
5836{
5837 char *type;
5838 int typelen, want_reply;
5839 struct Packet *pktout;
5840
5841 ssh_pkt_getstring(pktin, &type, &typelen);
5842 want_reply = ssh2_pkt_getbool(pktin);
5843
5844 /*
5845 * We currently don't support any global requests
5846 * at all, so we either ignore the request or
5847 * respond with REQUEST_FAILURE, depending on
5848 * want_reply.
5849 */
5850 if (want_reply) {
5851 pktout = ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE);
5852 ssh2_pkt_send(ssh, pktout);
5853 }
5854}
5855
5856static void ssh2_msg_channel_open(Ssh ssh, struct Packet *pktin)
5857{
5858 char *type;
5859 int typelen;
5860 char *peeraddr;
5861 int peeraddrlen;
5862 int peerport;
5863 char *error = NULL;
5864 struct ssh_channel *c;
5865 unsigned remid, winsize, pktsize;
5866 struct Packet *pktout;
5867
5868 ssh_pkt_getstring(pktin, &type, &typelen);
5869 c = snew(struct ssh_channel);
5870 c->ssh = ssh;
5871
5872 remid = ssh_pkt_getuint32(pktin);
5873 winsize = ssh_pkt_getuint32(pktin);
5874 pktsize = ssh_pkt_getuint32(pktin);
5875
5876 if (typelen == 3 && !memcmp(type, "x11", 3)) {
5877 char *addrstr;
5878
5879 ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
5880 addrstr = snewn(peeraddrlen+1, char);
5881 memcpy(addrstr, peeraddr, peeraddrlen);
5882 addrstr[peeraddrlen] = '\0';
5883 peerport = ssh_pkt_getuint32(pktin);
5884
5885 logeventf(ssh, "Received X11 connect request from %s:%d",
5886 addrstr, peerport);
5887
5888 if (!ssh->X11_fwd_enabled)
5889 error = "X11 forwarding is not enabled";
5890 else if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
5891 ssh->x11auth, addrstr, peerport,
5892 &ssh->cfg) != NULL) {
5893 error = "Unable to open an X11 connection";
5894 } else {
5895 logevent("Opening X11 forward connection succeeded");
5896 c->type = CHAN_X11;
5897 }
5898
5899 sfree(addrstr);
5900 } else if (typelen == 15 &&
5901 !memcmp(type, "forwarded-tcpip", 15)) {
5902 struct ssh_rportfwd pf, *realpf;
5903 char *dummy;
5904 int dummylen;
5905 ssh_pkt_getstring(pktin, &dummy, &dummylen);/* skip address */
5906 pf.sport = ssh_pkt_getuint32(pktin);
5907 ssh_pkt_getstring(pktin, &peeraddr, &peeraddrlen);
5908 peerport = ssh_pkt_getuint32(pktin);
5909 realpf = find234(ssh->rportfwds, &pf, NULL);
5910 logeventf(ssh, "Received remote port %d open request "
5911 "from %s:%d", pf.sport, peeraddr, peerport);
5912 if (realpf == NULL) {
5913 error = "Remote port is not recognised";
5914 } else {
5915 const char *e = pfd_newconnect(&c->u.pfd.s,
5916 realpf->dhost,
5917 realpf->dport, c,
05581745 5918 &ssh->cfg,
5919 realpf->pfrec->addressfamily);
51df0ab5 5920 logeventf(ssh, "Attempting to forward remote port to "
5921 "%s:%d", realpf->dhost, realpf->dport);
5922 if (e != NULL) {
5923 logeventf(ssh, "Port open failed: %s", e);
5924 error = "Port open failed";
5925 } else {
5926 logevent("Forwarded port opened successfully");
5927 c->type = CHAN_SOCKDATA;
5928 }
5929 }
5930 } else if (typelen == 22 &&
5931 !memcmp(type, "auth-agent@openssh.com", 3)) {
5932 if (!ssh->agentfwd_enabled)
5933 error = "Agent forwarding is not enabled";
5934 else {
5935 c->type = CHAN_AGENT; /* identify channel type */
5936 c->u.a.lensofar = 0;
5937 }
5938 } else {
5939 error = "Unsupported channel type requested";
5940 }
5941
5942 c->remoteid = remid;
5943 if (error) {
5944 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE);
5945 ssh2_pkt_adduint32(pktout, c->remoteid);
5946 ssh2_pkt_adduint32(pktout, SSH2_OPEN_CONNECT_FAILED);
5947 ssh2_pkt_addstring(pktout, error);
5948 ssh2_pkt_addstring(pktout, "en"); /* language tag */
5949 ssh2_pkt_send(ssh, pktout);
5950 logeventf(ssh, "Rejected channel open: %s", error);
5951 sfree(c);
5952 } else {
5953 c->localid = alloc_channel_id(ssh);
5954 c->closes = 0;
5955 c->v.v2.locwindow = OUR_V2_WINSIZE;
5956 c->v.v2.remwindow = winsize;
5957 c->v.v2.remmaxpkt = pktsize;
5958 bufchain_init(&c->v.v2.outbuffer);
5959 add234(ssh->channels, c);
5960 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
5961 ssh2_pkt_adduint32(pktout, c->remoteid);
5962 ssh2_pkt_adduint32(pktout, c->localid);
5963 ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);
5964 ssh2_pkt_adduint32(pktout, 0x4000UL); /* our max pkt size */
5965 ssh2_pkt_send(ssh, pktout);
5966 }
5967}
5968
783415f8 5969/*
7cca0d81 5970 * Handle the SSH2 userauth and connection layers.
5971 */
ff3187f6 5972static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen,
5973 struct Packet *pktin)
7cca0d81 5974{
51470298 5975 struct do_ssh2_authconn_state {
5976 enum {
5977 AUTH_INVALID, AUTH_PUBLICKEY_AGENT, AUTH_PUBLICKEY_FILE,
5978 AUTH_PASSWORD,
5979 AUTH_KEYBOARD_INTERACTIVE
5980 } method;
5981 enum {
5982 AUTH_TYPE_NONE,
5983 AUTH_TYPE_PUBLICKEY,
5984 AUTH_TYPE_PUBLICKEY_OFFER_LOUD,
5985 AUTH_TYPE_PUBLICKEY_OFFER_QUIET,
5986 AUTH_TYPE_PASSWORD,
5987 AUTH_TYPE_KEYBOARD_INTERACTIVE,
5988 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
5989 } type;
5990 int gotit, need_pw, can_pubkey, can_passwd, can_keyb_inter;
6ac3a551 5991 int tried_pubkey_config, tried_agent;
5992 int kbd_inter_running, kbd_inter_refused;
51470298 5993 int we_are_in;
5994 int num_prompts, curr_prompt, echo;
5995 char username[100];
5996 int got_username;
85fdbe25 5997 char pwprompt[512];
51470298 5998 char password[100];
5999 void *publickey_blob;
6000 int publickey_bloblen;
6001 unsigned char request[5], *response, *p;
6002 int responselen;
6003 int keyi, nkeys;
6004 int authed;
6005 char *pkblob, *alg, *commentp;
6006 int pklen, alglen, commentlen;
6007 int siglen, retlen, len;
6008 char *q, *agentreq, *ret;
6009 int try_send;
73feed4f 6010 int num_env, env_left, env_ok;
ff3187f6 6011 struct Packet *pktout;
51470298 6012 };
6013 crState(do_ssh2_authconn_state);
6014
6015 crBegin(ssh->do_ssh2_authconn_crstate);
e5574168 6016
7cca0d81 6017 /*
6018 * Request userauth protocol, and await a response to it.
6019 */
ff3187f6 6020 s->pktout = ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
6021 ssh2_pkt_addstring(s->pktout, "ssh-userauth");
6022 ssh2_pkt_send(ssh, s->pktout);
6023 crWaitUntilV(pktin);
6024 if (pktin->type != SSH2_MSG_SERVICE_ACCEPT) {
6b5cf8b4 6025 bombout(("Server refused user authentication protocol"));
7ffdbc1a 6026 crStopV;
8d5de777 6027 }
7cca0d81 6028
6029 /*
1408a877 6030 * We repeat this whole loop, including the username prompt,
6031 * until we manage a successful authentication. If the user
51470298 6032 * types the wrong _password_, they can be sent back to the
6033 * beginning to try another username, if this is configured on.
6034 * (If they specify a username in the config, they are never
6035 * asked, even if they do give a wrong password.)
1408a877 6036 *
6037 * I think this best serves the needs of
6038 *
6039 * - the people who have no configuration, no keys, and just
6040 * want to try repeated (username,password) pairs until they
6041 * type both correctly
6042 *
6043 * - people who have keys and configuration but occasionally
6044 * need to fall back to passwords
6045 *
6046 * - people with a key held in Pageant, who might not have
6047 * logged in to a particular machine before; so they want to
6048 * type a username, and then _either_ their key will be
6049 * accepted, _or_ they will type a password. If they mistype
6050 * the username they will want to be able to get back and
6051 * retype it!
7cca0d81 6052 */
51470298 6053 s->username[0] = '\0';
6054 s->got_username = FALSE;
1408a877 6055 do {
1408a877 6056 /*
6057 * Get a username.
6058 */
86916870 6059 if (s->got_username && !ssh->cfg.change_username) {
5bb641e1 6060 /*
6061 * We got a username last time round this loop, and
6062 * with change_username turned off we don't try to get
6063 * it again.
6064 */
aa09f7d0 6065 } else if (!*ssh->cfg.username) {
c0a81592 6066 if (ssh_get_line && !ssh_getline_pw_only) {
32874aea 6067 if (!ssh_get_line("login as: ",
51470298 6068 s->username, sizeof(s->username), FALSE)) {
32874aea 6069 /*
6070 * get_line failed to get a username.
6071 * Terminate.
6072 */
6073 logevent("No username provided. Abandoning session.");
ac934965 6074 ssh->close_expected = TRUE;
3bb2f322 6075 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 6076 crStopV;
32874aea 6077 }
6078 } else {
51470298 6079 int ret; /* need not be saved across crReturn */
6080 c_write_str(ssh, "login as: ");
6081 ssh->send_ok = 1;
6082 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
0405e71f 6083 do {
ff3187f6 6084 crWaitUntilV(!pktin);
51470298 6085 ret = process_userpass_input(ssh, in, inlen);
0405e71f 6086 } while (ret == 0);
6087 if (ret < 0)
6088 cleanup_exit(0);
4ca0c9d1 6089 c_write_str(ssh, "\r\n");
32874aea 6090 }
51470298 6091 s->username[strcspn(s->username, "\n\r")] = '\0';
7cca0d81 6092 } else {
57356d63 6093 char *stuff;
86916870 6094 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
51470298 6095 s->username[sizeof(s->username)-1] = '\0';
65a22376 6096 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
57356d63 6097 stuff = dupprintf("Using username \"%s\".\r\n", s->username);
51470298 6098 c_write_str(ssh, stuff);
57356d63 6099 sfree(stuff);
7cca0d81 6100 }
6101 }
51470298 6102 s->got_username = TRUE;
7cca0d81 6103
65a22376 6104 /*
1408a877 6105 * Send an authentication request using method "none": (a)
6106 * just in case it succeeds, and (b) so that we know what
6107 * authentication methods we can usefully try next.
65a22376 6108 */
51470298 6109 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6110
ff3187f6 6111 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6112 ssh2_pkt_addstring(s->pktout, s->username);
6113 ssh2_pkt_addstring(s->pktout, "ssh-connection");/* service requested */
6114 ssh2_pkt_addstring(s->pktout, "none"); /* method */
6115 ssh2_pkt_send(ssh, s->pktout);
51470298 6116 s->type = AUTH_TYPE_NONE;
6117 s->gotit = FALSE;
6118 s->we_are_in = FALSE;
6119
6120 s->tried_pubkey_config = FALSE;
6121 s->tried_agent = FALSE;
51470298 6122 s->kbd_inter_running = FALSE;
6ac3a551 6123 s->kbd_inter_refused = FALSE;
86916870 6124 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
9a30e26b 6125 if (!filename_is_null(ssh->cfg.keyfile)) {
231ee168 6126 int keytype;
6c6d9ed9 6127 logeventf(ssh, "Reading private key file \"%.150s\"",
6128 filename_to_str(&ssh->cfg.keyfile));
9a30e26b 6129 keytype = key_type(&ssh->cfg.keyfile);
51470298 6130 if (keytype == SSH_KEYTYPE_SSH2) {
6131 s->publickey_blob =
9a30e26b 6132 ssh2_userkey_loadpub(&ssh->cfg.keyfile, NULL,
222d54dc 6133 &s->publickey_bloblen, NULL);
51470298 6134 } else {
57356d63 6135 char *msgbuf;
c2ad7d0d 6136 logeventf(ssh, "Unable to use this key file (%s)",
a8327734 6137 key_type_to_str(keytype));
57356d63 6138 msgbuf = dupprintf("Unable to use key file \"%.150s\""
6c6d9ed9 6139 " (%s)\r\n",
6140 filename_to_str(&ssh->cfg.keyfile),
57356d63 6141 key_type_to_str(keytype));
51470298 6142 c_write_str(ssh, msgbuf);
57356d63 6143 sfree(msgbuf);
51470298 6144 s->publickey_blob = NULL;
231ee168 6145 }
396778f1 6146 } else
51470298 6147 s->publickey_blob = NULL;
65a22376 6148
1408a877 6149 while (1) {
6150 /*
6151 * Wait for the result of the last authentication request.
6152 */
51470298 6153 if (!s->gotit)
ff3187f6 6154 crWaitUntilV(pktin);
6155 while (pktin->type == SSH2_MSG_USERAUTH_BANNER) {
32874aea 6156 char *banner;
6157 int size;
6158 /*
6159 * Don't show the banner if we're operating in
6160 * non-verbose non-interactive mode. (It's probably
6161 * a script, which means nobody will read the
6162 * banner _anyway_, and moreover the printing of
6163 * the banner will screw up processing on the
6164 * output of (say) plink.)
6165 */
6166 if (flags & (FLAG_VERBOSE | FLAG_INTERACTIVE)) {
ff3187f6 6167 ssh_pkt_getstring(pktin, &banner, &size);
32874aea 6168 if (banner)
51470298 6169 c_write_untrusted(ssh, banner, size);
32874aea 6170 }
ff3187f6 6171 crWaitUntilV(pktin);
1408a877 6172 }
ff3187f6 6173 if (pktin->type == SSH2_MSG_USERAUTH_SUCCESS) {
1408a877 6174 logevent("Access granted");
51470298 6175 s->we_are_in = TRUE;
1408a877 6176 break;
6177 }
65a22376 6178
51470298 6179 if (s->kbd_inter_running &&
ff3187f6 6180 pktin->type == SSH2_MSG_USERAUTH_INFO_REQUEST) {
b3186d64 6181 /*
45068b27 6182 * This is either a further set-of-prompts packet
6183 * in keyboard-interactive authentication, or it's
6184 * the same one and we came back here with `gotit'
6185 * set. In the former case, we must reset the
6186 * curr_prompt variable.
b3186d64 6187 */
51470298 6188 if (!s->gotit)
6189 s->curr_prompt = 0;
4c6e53e3 6190 } else if (pktin->type == SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ) {
6191 /* FIXME: perhaps we should support this? */
6192 bombout(("PASSWD_CHANGEREQ not yet supported"));
6193 crStopV;
ff3187f6 6194 } else if (pktin->type != SSH2_MSG_USERAUTH_FAILURE) {
6b5cf8b4 6195 bombout(("Strange packet received during authentication: type %d",
ff3187f6 6196 pktin->type));
7ffdbc1a 6197 crStopV;
65a22376 6198 }
6199
51470298 6200 s->gotit = FALSE;
65a22376 6201
1408a877 6202 /*
6203 * OK, we're now sitting on a USERAUTH_FAILURE message, so
6204 * we can look at the string in it and know what we can
6205 * helpfully try next.
6206 */
ff3187f6 6207 if (pktin->type == SSH2_MSG_USERAUTH_FAILURE) {
1408a877 6208 char *methods;
6209 int methlen;
ff3187f6 6210 ssh_pkt_getstring(pktin, &methods, &methlen);
51470298 6211 s->kbd_inter_running = FALSE;
ff3187f6 6212 if (!ssh2_pkt_getbool(pktin)) {
1408a877 6213 /*
6214 * We have received an unequivocal Access
6215 * Denied. This can translate to a variety of
6216 * messages:
6217 *
6218 * - if we'd just tried "none" authentication,
6219 * it's not worth printing anything at all
6220 *
6221 * - if we'd just tried a public key _offer_,
6222 * the message should be "Server refused our
6223 * key" (or no message at all if the key
6224 * came from Pageant)
6225 *
6226 * - if we'd just tried anything else, the
6227 * message really should be "Access denied".
6228 *
6229 * Additionally, if we'd just tried password
6230 * authentication, we should break out of this
6231 * whole loop so as to go back to the username
91f57d1f 6232 * prompt (iff we're configured to allow
6233 * username change attempts).
1408a877 6234 */
51470298 6235 if (s->type == AUTH_TYPE_NONE) {
1408a877 6236 /* do nothing */
51470298 6237 } else if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD ||
6238 s->type == AUTH_TYPE_PUBLICKEY_OFFER_QUIET) {
6239 if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD)
6240 c_write_str(ssh, "Server refused our key\r\n");
1408a877 6241 logevent("Server refused public key");
51470298 6242 } else if (s->type==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET) {
4bdf7c46 6243 /* server declined keyboard-interactive; ignore */
1408a877 6244 } else {
51470298 6245 c_write_str(ssh, "Access denied\r\n");
1408a877 6246 logevent("Access denied");
91f57d1f 6247 if (s->type == AUTH_TYPE_PASSWORD &&
6248 ssh->cfg.change_username) {
6c9dce7c 6249 /* XXX perhaps we should allow
6250 * keyboard-interactive to do this too? */
51470298 6251 s->we_are_in = FALSE;
1408a877 6252 break;
6253 }
6254 }
6255 } else {
51470298 6256 c_write_str(ssh, "Further authentication required\r\n");
1408a877 6257 logevent("Further authentication required");
6258 }
65a22376 6259
51470298 6260 s->can_pubkey =
32874aea 6261 in_commasep_string("publickey", methods, methlen);
51470298 6262 s->can_passwd =
32874aea 6263 in_commasep_string("password", methods, methlen);
86916870 6264 s->can_keyb_inter = ssh->cfg.try_ki_auth &&
761187b6 6265 in_commasep_string("keyboard-interactive", methods, methlen);
1408a877 6266 }
65a22376 6267
51470298 6268 s->method = 0;
6269 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
954a9540 6270 s->need_pw = FALSE;
65a22376 6271
0405e71f 6272 /*
6273 * Most password/passphrase prompts will be
6274 * non-echoing, so we set this to 0 by default.
6275 * Exception is that some keyboard-interactive prompts
6276 * can be echoing, in which case we'll set this to 1.
6277 */
51470298 6278 s->echo = 0;
0405e71f 6279
51470298 6280 if (!s->method && s->can_pubkey &&
6281 agent_exists() && !s->tried_agent) {
1983e559 6282 /*
6283 * Attempt public-key authentication using Pageant.
6284 */
1983e559 6285 void *r;
51470298 6286 s->authed = FALSE;
1983e559 6287
51470298 6288 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6289 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
00db133f 6290
51470298 6291 s->tried_agent = TRUE;
1983e559 6292
6293 logevent("Pageant is running. Requesting keys.");
6294
6295 /* Request the keys held by the agent. */
51470298 6296 PUT_32BIT(s->request, 1);
6297 s->request[4] = SSH2_AGENTC_REQUEST_IDENTITIES;
839f10db 6298 if (!agent_query(s->request, 5, &r, &s->responselen,
6299 ssh_agent_callback, ssh)) {
6300 do {
6301 crReturnV;
ff3187f6 6302 if (pktin) {
839f10db 6303 bombout(("Unexpected data from server while"
6304 " waiting for agent response"));
6305 crStopV;
6306 }
ff3187f6 6307 } while (pktin || inlen > 0);
839f10db 6308 r = ssh->agent_response;
6309 s->responselen = ssh->agent_response_len;
6310 }
51470298 6311 s->response = (unsigned char *) r;
6312 if (s->response && s->responselen >= 5 &&
6313 s->response[4] == SSH2_AGENT_IDENTITIES_ANSWER) {
6314 s->p = s->response + 5;
6315 s->nkeys = GET_32BIT(s->p);
6316 s->p += 4;
32874aea 6317 {
6318 char buf[64];
51470298 6319 sprintf(buf, "Pageant has %d SSH2 keys", s->nkeys);
32874aea 6320 logevent(buf);
6321 }
51470298 6322 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
2d466ffd 6323 void *vret;
1983e559 6324
32874aea 6325 {
6326 char buf[64];
51470298 6327 sprintf(buf, "Trying Pageant key #%d", s->keyi);
32874aea 6328 logevent(buf);
6329 }
51470298 6330 s->pklen = GET_32BIT(s->p);
6331 s->p += 4;
6332 if (s->publickey_blob &&
6333 s->pklen == s->publickey_bloblen &&
6334 !memcmp(s->p, s->publickey_blob,
6335 s->publickey_bloblen)) {
396778f1 6336 logevent("This key matches configured key file");
51470298 6337 s->tried_pubkey_config = 1;
396778f1 6338 }
d8baa528 6339 s->pkblob = (char *)s->p;
51470298 6340 s->p += s->pklen;
6341 s->alglen = GET_32BIT(s->pkblob);
6342 s->alg = s->pkblob + 4;
6343 s->commentlen = GET_32BIT(s->p);
6344 s->p += 4;
d8baa528 6345 s->commentp = (char *)s->p;
51470298 6346 s->p += s->commentlen;
ff3187f6 6347 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6348 ssh2_pkt_addstring(s->pktout, s->username);
6349 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6350 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6351 ssh2_pkt_addbool(s->pktout, FALSE); /* no signature included */
6352 ssh2_pkt_addstring_start(s->pktout);
6353 ssh2_pkt_addstring_data(s->pktout, s->alg, s->alglen);
6354 ssh2_pkt_addstring_start(s->pktout);
6355 ssh2_pkt_addstring_data(s->pktout, s->pkblob, s->pklen);
6356 ssh2_pkt_send(ssh, s->pktout);
6357
6358 crWaitUntilV(pktin);
6359 if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
1983e559 6360 logevent("Key refused");
6361 continue;
6362 }
6363
32874aea 6364 if (flags & FLAG_VERBOSE) {
51470298 6365 c_write_str(ssh, "Authenticating with "
6366 "public key \"");
6367 c_write(ssh, s->commentp, s->commentlen);
6368 c_write_str(ssh, "\" from agent\r\n");
32874aea 6369 }
1983e559 6370
6371 /*
6372 * Server is willing to accept the key.
6373 * Construct a SIGN_REQUEST.
6374 */
ff3187f6 6375 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6376 ssh2_pkt_addstring(s->pktout, s->username);
6377 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6378 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6379 ssh2_pkt_addbool(s->pktout, TRUE);
6380 ssh2_pkt_addstring_start(s->pktout);
6381 ssh2_pkt_addstring_data(s->pktout, s->alg, s->alglen);
6382 ssh2_pkt_addstring_start(s->pktout);
6383 ssh2_pkt_addstring_data(s->pktout, s->pkblob, s->pklen);
6384
6385 s->siglen = s->pktout->length - 5 + 4 + 20;
dda87a28 6386 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
6387 s->siglen -= 4;
51470298 6388 s->len = 1; /* message type */
6389 s->len += 4 + s->pklen; /* key blob */
6390 s->len += 4 + s->siglen; /* data to sign */
6391 s->len += 4; /* flags */
3d88e64d 6392 s->agentreq = snewn(4 + s->len, char);
51470298 6393 PUT_32BIT(s->agentreq, s->len);
6394 s->q = s->agentreq + 4;
6395 *s->q++ = SSH2_AGENTC_SIGN_REQUEST;
6396 PUT_32BIT(s->q, s->pklen);
6397 s->q += 4;
6398 memcpy(s->q, s->pkblob, s->pklen);
6399 s->q += s->pklen;
6400 PUT_32BIT(s->q, s->siglen);
6401 s->q += 4;
1983e559 6402 /* Now the data to be signed... */
dda87a28 6403 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
6404 PUT_32BIT(s->q, 20);
6405 s->q += 4;
6406 }
51470298 6407 memcpy(s->q, ssh->v2_session_id, 20);
6408 s->q += 20;
ff3187f6 6409 memcpy(s->q, s->pktout->data + 5,
6410 s->pktout->length - 5);
6411 s->q += s->pktout->length - 5;
1983e559 6412 /* And finally the (zero) flags word. */
51470298 6413 PUT_32BIT(s->q, 0);
839f10db 6414 if (!agent_query(s->agentreq, s->len + 4,
6415 &vret, &s->retlen,
6416 ssh_agent_callback, ssh)) {
6417 do {
6418 crReturnV;
ff3187f6 6419 if (pktin) {
839f10db 6420 bombout(("Unexpected data from server"
6421 " while waiting for agent"
6422 " response"));
6423 crStopV;
6424 }
ff3187f6 6425 } while (pktin || inlen > 0);
839f10db 6426 vret = ssh->agent_response;
6427 s->retlen = ssh->agent_response_len;
6428 }
51470298 6429 s->ret = vret;
6430 sfree(s->agentreq);
6431 if (s->ret) {
6432 if (s->ret[4] == SSH2_AGENT_SIGN_RESPONSE) {
1983e559 6433 logevent("Sending Pageant's response");
ff3187f6 6434 ssh2_add_sigblob(ssh, s->pktout,
6435 s->pkblob, s->pklen,
51470298 6436 s->ret + 9,
6437 GET_32BIT(s->ret + 5));
ff3187f6 6438 ssh2_pkt_send(ssh, s->pktout);
51470298 6439 s->authed = TRUE;
1983e559 6440 break;
6441 } else {
32874aea 6442 logevent
6443 ("Pageant failed to answer challenge");
51470298 6444 sfree(s->ret);
1983e559 6445 }
6446 }
6447 }
51470298 6448 if (s->authed)
1983e559 6449 continue;
6450 }
29b1d0b3 6451 sfree(s->response);
1983e559 6452 }
6453
51470298 6454 if (!s->method && s->can_pubkey && s->publickey_blob
6455 && !s->tried_pubkey_config) {
1408a877 6456 unsigned char *pub_blob;
6457 char *algorithm, *comment;
6458 int pub_blob_len;
65a22376 6459
51470298 6460 s->tried_pubkey_config = TRUE;
65a22376 6461
51470298 6462 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6463 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
00db133f 6464
65a22376 6465 /*
1408a877 6466 * Try the public key supplied in the configuration.
6467 *
6468 * First, offer the public blob to see if the server is
6469 * willing to accept it.
65a22376 6470 */
d8baa528 6471 pub_blob =
9a30e26b 6472 (unsigned char *)ssh2_userkey_loadpub(&ssh->cfg.keyfile,
d8baa528 6473 &algorithm,
222d54dc 6474 &pub_blob_len,
6475 NULL);
1408a877 6476 if (pub_blob) {
ff3187f6 6477 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6478 ssh2_pkt_addstring(s->pktout, s->username);
6479 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6480 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6481 ssh2_pkt_addbool(s->pktout, FALSE); /* no signature included */
6482 ssh2_pkt_addstring(s->pktout, algorithm);
6483 ssh2_pkt_addstring_start(s->pktout);
6484 ssh2_pkt_addstring_data(s->pktout, (char *)pub_blob,
d8baa528 6485 pub_blob_len);
ff3187f6 6486 ssh2_pkt_send(ssh, s->pktout);
a03c9f9c 6487 logevent("Offered public key");
1408a877 6488
ff3187f6 6489 crWaitUntilV(pktin);
6490 if (pktin->type != SSH2_MSG_USERAUTH_PK_OK) {
51470298 6491 s->gotit = TRUE;
6492 s->type = AUTH_TYPE_PUBLICKEY_OFFER_LOUD;
32874aea 6493 continue; /* key refused; give up on it */
1408a877 6494 }
65a22376 6495
1408a877 6496 logevent("Offer of public key accepted");
65a22376 6497 /*
1408a877 6498 * Actually attempt a serious authentication using
6499 * the key.
65a22376 6500 */
9a30e26b 6501 if (ssh2_userkey_encrypted(&ssh->cfg.keyfile, &comment)) {
51470298 6502 sprintf(s->pwprompt,
32874aea 6503 "Passphrase for key \"%.100s\": ",
6504 comment);
51470298 6505 s->need_pw = TRUE;
1408a877 6506 } else {
51470298 6507 s->need_pw = FALSE;
1408a877 6508 }
4e520718 6509 if (flags & FLAG_VERBOSE) {
6510 c_write_str(ssh, "Authenticating with public key \"");
6511 c_write_str(ssh, comment);
6512 c_write_str(ssh, "\"\r\n");
6513 }
51470298 6514 s->method = AUTH_PUBLICKEY_FILE;
65a22376 6515 }
1408a877 6516 }
6517
6f64ce13 6518 if (!s->method && s->can_keyb_inter && !s->kbd_inter_refused &&
6519 !s->kbd_inter_running) {
51470298 6520 s->method = AUTH_KEYBOARD_INTERACTIVE;
6521 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
af659722 6522
51470298 6523 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6524 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
00db133f 6525
ff3187f6 6526 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6527 ssh2_pkt_addstring(s->pktout, s->username);
6528 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6529 ssh2_pkt_addstring(s->pktout, "keyboard-interactive"); /* method */
6530 ssh2_pkt_addstring(s->pktout, ""); /* lang */
6531 ssh2_pkt_addstring(s->pktout, "");
6532 ssh2_pkt_send(ssh, s->pktout);
6533
6534 crWaitUntilV(pktin);
6535 if (pktin->type != SSH2_MSG_USERAUTH_INFO_REQUEST) {
6536 if (pktin->type == SSH2_MSG_USERAUTH_FAILURE)
51470298 6537 s->gotit = TRUE;
af659722 6538 logevent("Keyboard-interactive authentication refused");
51470298 6539 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET;
6ac3a551 6540 s->kbd_inter_refused = TRUE; /* don't try it again */
af659722 6541 continue;
6542 }
6543
51470298 6544 s->kbd_inter_running = TRUE;
6545 s->curr_prompt = 0;
af659722 6546 }
6547
51470298 6548 if (s->kbd_inter_running) {
6549 s->method = AUTH_KEYBOARD_INTERACTIVE;
6550 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
af659722 6551
51470298 6552 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6553 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
00db133f 6554
51470298 6555 if (s->curr_prompt == 0) {
45068b27 6556 /*
6557 * We've got a fresh USERAUTH_INFO_REQUEST.
6558 * Display header data, and start going through
6559 * the prompts.
6560 */
6561 char *name, *inst, *lang;
6562 int name_len, inst_len, lang_len;
6563
ff3187f6 6564 ssh_pkt_getstring(pktin, &name, &name_len);
6565 ssh_pkt_getstring(pktin, &inst, &inst_len);
6566 ssh_pkt_getstring(pktin, &lang, &lang_len);
45068b27 6567 if (name_len > 0) {
51470298 6568 c_write_untrusted(ssh, name, name_len);
6569 c_write_str(ssh, "\r\n");
45068b27 6570 }
6571 if (inst_len > 0) {
51470298 6572 c_write_untrusted(ssh, inst, inst_len);
6573 c_write_str(ssh, "\r\n");
45068b27 6574 }
ff3187f6 6575 s->num_prompts = ssh_pkt_getuint32(pktin);
45068b27 6576 }
af659722 6577
45068b27 6578 /*
6579 * If there are prompts remaining in the packet,
6580 * display one and get a response.
6581 */
51470298 6582 if (s->curr_prompt < s->num_prompts) {
45068b27 6583 char *prompt;
6584 int prompt_len;
af659722 6585
ff3187f6 6586 ssh_pkt_getstring(pktin, &prompt, &prompt_len);
45068b27 6587 if (prompt_len > 0) {
85fdbe25 6588 static const char trunc[] = "<prompt truncated>: ";
6589 static const int prlen = sizeof(s->pwprompt) -
6590 lenof(trunc);
6591 if (prompt_len > prlen) {
6592 memcpy(s->pwprompt, prompt, prlen);
6593 strcpy(s->pwprompt + prlen, trunc);
6594 } else {
6595 memcpy(s->pwprompt, prompt, prompt_len);
6596 s->pwprompt[prompt_len] = '\0';
6597 }
45068b27 6598 } else {
51470298 6599 strcpy(s->pwprompt,
45068b27 6600 "<server failed to send prompt>: ");
6601 }
ff3187f6 6602 s->echo = ssh2_pkt_getbool(pktin);
51470298 6603 s->need_pw = TRUE;
45068b27 6604 } else
51470298 6605 s->need_pw = FALSE;
af659722 6606 }
6607
51470298 6608 if (!s->method && s->can_passwd) {
6609 s->method = AUTH_PASSWORD;
6610 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
6611 ssh->pkt_ctx |= SSH2_PKTCTX_PASSWORD;
6612 sprintf(s->pwprompt, "%.90s@%.90s's password: ", s->username,
6613 ssh->savedhost);
6614 s->need_pw = TRUE;
1408a877 6615 }
6616
51470298 6617 if (s->need_pw) {
fa17a66e 6618 if (ssh_get_line) {
51470298 6619 if (!ssh_get_line(s->pwprompt, s->password,
6620 sizeof(s->password), TRUE)) {
1408a877 6621 /*
fa17a66e 6622 * get_line failed to get a password (for
6623 * example because one was supplied on the
6624 * command line which has already failed to
6625 * work). Terminate.
1408a877 6626 */
ff3187f6 6627 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
6628 ssh2_pkt_adduint32(s->pktout,SSH2_DISCONNECT_BY_APPLICATION);
6629 ssh2_pkt_addstring(s->pktout, "No more passwords available"
51470298 6630 " to try");
ff3187f6 6631 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
590f6a5f 6632 ssh2_pkt_send_noqueue(ssh, s->pktout);
247308b5 6633 logevent("Unable to authenticate");
a8327734 6634 connection_fatal(ssh->frontend,
6635 "Unable to authenticate");
ac934965 6636 ssh->close_expected = TRUE;
3bb2f322 6637 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 6638 crStopV;
1408a877 6639 }
6640 } else {
51470298 6641 int ret; /* need not be saved across crReturn */
6642 c_write_untrusted(ssh, s->pwprompt, strlen(s->pwprompt));
6643 ssh->send_ok = 1;
1408a877 6644
51470298 6645 setup_userpass_input(ssh, s->password,
6646 sizeof(s->password), s->echo);
0405e71f 6647 do {
ff3187f6 6648 crWaitUntilV(!pktin);
51470298 6649 ret = process_userpass_input(ssh, in, inlen);
0405e71f 6650 } while (ret == 0);
6651 if (ret < 0)
6652 cleanup_exit(0);
51470298 6653 c_write_str(ssh, "\r\n");
65a22376 6654 }
65a22376 6655 }
65a22376 6656
51470298 6657 if (s->method == AUTH_PUBLICKEY_FILE) {
1408a877 6658 /*
6659 * We have our passphrase. Now try the actual authentication.
6660 */
6661 struct ssh2_userkey *key;
222d54dc 6662 const char *error = NULL;
65a22376 6663
222d54dc 6664 key = ssh2_load_userkey(&ssh->cfg.keyfile, s->password,
6665 &error);
1408a877 6666 if (key == SSH2_WRONG_PASSPHRASE || key == NULL) {
6667 if (key == SSH2_WRONG_PASSPHRASE) {
51470298 6668 c_write_str(ssh, "Wrong passphrase\r\n");
6669 s->tried_pubkey_config = FALSE;
1408a877 6670 } else {
222d54dc 6671 c_write_str(ssh, "Unable to load private key (");
6672 c_write_str(ssh, error);
6673 c_write_str(ssh, ")\r\n");
51470298 6674 s->tried_pubkey_config = TRUE;
1408a877 6675 }
6676 /* Send a spurious AUTH_NONE to return to the top. */
ff3187f6 6677 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6678 ssh2_pkt_addstring(s->pktout, s->username);
6679 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6680 ssh2_pkt_addstring(s->pktout, "none"); /* method */
6681 ssh2_pkt_send(ssh, s->pktout);
51470298 6682 s->type = AUTH_TYPE_NONE;
1408a877 6683 } else {
1dd353b5 6684 unsigned char *pkblob, *sigblob, *sigdata;
6685 int pkblob_len, sigblob_len, sigdata_len;
dda87a28 6686 int p;
65a22376 6687
1408a877 6688 /*
6689 * We have loaded the private key and the server
6690 * has announced that it's willing to accept it.
6691 * Hallelujah. Generate a signature and send it.
6692 */
ff3187f6 6693 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6694 ssh2_pkt_addstring(s->pktout, s->username);
6695 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6696 ssh2_pkt_addstring(s->pktout, "publickey"); /* method */
6697 ssh2_pkt_addbool(s->pktout, TRUE);
6698 ssh2_pkt_addstring(s->pktout, key->alg->name);
1dd353b5 6699 pkblob = key->alg->public_blob(key->data, &pkblob_len);
ff3187f6 6700 ssh2_pkt_addstring_start(s->pktout);
6701 ssh2_pkt_addstring_data(s->pktout, (char *)pkblob, pkblob_len);
1408a877 6702
6703 /*
6704 * The data to be signed is:
6705 *
6706 * string session-id
6707 *
6708 * followed by everything so far placed in the
6709 * outgoing packet.
6710 */
ff3187f6 6711 sigdata_len = s->pktout->length - 5 + 4 + 20;
dda87a28 6712 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
6713 sigdata_len -= 4;
92d60585 6714 sigdata = snewn(sigdata_len, unsigned char);
dda87a28 6715 p = 0;
6716 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
6717 PUT_32BIT(sigdata+p, 20);
6718 p += 4;
6719 }
6720 memcpy(sigdata+p, ssh->v2_session_id, 20); p += 20;
ff3187f6 6721 memcpy(sigdata+p, s->pktout->data + 5,
6722 s->pktout->length - 5);
6723 p += s->pktout->length - 5;
dda87a28 6724 assert(p == sigdata_len);
d8baa528 6725 sigblob = key->alg->sign(key->data, (char *)sigdata,
1dd353b5 6726 sigdata_len, &sigblob_len);
ff3187f6 6727 ssh2_add_sigblob(ssh, s->pktout, pkblob, pkblob_len,
1dd353b5 6728 sigblob, sigblob_len);
6729 sfree(pkblob);
6730 sfree(sigblob);
1408a877 6731 sfree(sigdata);
6732
ff3187f6 6733 ssh2_pkt_send(ssh, s->pktout);
51470298 6734 s->type = AUTH_TYPE_PUBLICKEY;
75374b2f 6735 key->alg->freekey(key->data);
1408a877 6736 }
51470298 6737 } else if (s->method == AUTH_PASSWORD) {
65a22376 6738 /*
1408a877 6739 * We send the password packet lumped tightly together with
6740 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
6741 * string long enough to make the total length of the two
6742 * packets constant. This should ensure that a passive
6743 * listener doing traffic analyis can't work out the length
6744 * of the password.
6745 *
6746 * For this to work, we need an assumption about the
6747 * maximum length of the password packet. I think 256 is
6748 * pretty conservative. Anyone using a password longer than
6749 * that probably doesn't have much to worry about from
6750 * people who find out how long their password is!
65a22376 6751 */
ff3187f6 6752 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
6753 ssh2_pkt_addstring(s->pktout, s->username);
6754 ssh2_pkt_addstring(s->pktout, "ssh-connection"); /* service requested */
6755 ssh2_pkt_addstring(s->pktout, "password");
6756 ssh2_pkt_addbool(s->pktout, FALSE);
6757 dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
6758 ssh2_pkt_addstring(s->pktout, s->password);
1409c1b3 6759 memset(s->password, 0, sizeof(s->password));
ff3187f6 6760 end_log_omission(ssh, s->pktout);
6761 ssh2_pkt_defer(ssh, s->pktout);
65a22376 6762 /*
1408a877 6763 * We'll include a string that's an exact multiple of the
6764 * cipher block size. If the cipher is NULL for some
6765 * reason, we don't do this trick at all because we gain
6766 * nothing by it.
65a22376 6767 */
51470298 6768 if (ssh->cscipher) {
32874aea 6769 int stringlen, i;
6770
51470298 6771 stringlen = (256 - ssh->deferred_len);
6772 stringlen += ssh->cscipher->blksize - 1;
6773 stringlen -= (stringlen % ssh->cscipher->blksize);
6774 if (ssh->cscomp) {
32874aea 6775 /*
6776 * Temporarily disable actual compression,
6777 * so we can guarantee to get this string
6778 * exactly the length we want it. The
6779 * compression-disabling routine should
6780 * return an integer indicating how many
6781 * bytes we should adjust our string length
6782 * by.
6783 */
5366aed8 6784 stringlen -=
6785 ssh->cscomp->disable_compression(ssh->cs_comp_ctx);
32874aea 6786 }
ff3187f6 6787 s->pktout = ssh2_pkt_init(SSH2_MSG_IGNORE);
6788 ssh2_pkt_addstring_start(s->pktout);
6e9e9520 6789 for (i = 0; i < stringlen; i++) {
32874aea 6790 char c = (char) random_byte();
ff3187f6 6791 ssh2_pkt_addstring_data(s->pktout, &c, 1);
65a22376 6792 }
ff3187f6 6793 ssh2_pkt_defer(ssh, s->pktout);
65a22376 6794 }
51470298 6795 ssh_pkt_defersend(ssh);
0d43337a 6796 logevent("Sent password");
51470298 6797 s->type = AUTH_TYPE_PASSWORD;
6798 } else if (s->method == AUTH_KEYBOARD_INTERACTIVE) {
6799 if (s->curr_prompt == 0) {
ff3187f6 6800 s->pktout = ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE);
6801 ssh2_pkt_adduint32(s->pktout, s->num_prompts);
45068b27 6802 }
51470298 6803 if (s->need_pw) { /* only add pw if we just got one! */
ff3187f6 6804 dont_log_password(ssh, s->pktout, PKTLOG_BLANK);
6805 ssh2_pkt_addstring(s->pktout, s->password);
51470298 6806 memset(s->password, 0, sizeof(s->password));
ff3187f6 6807 end_log_omission(ssh, s->pktout);
51470298 6808 s->curr_prompt++;
45068b27 6809 }
51470298 6810 if (s->curr_prompt >= s->num_prompts) {
ff3187f6 6811 ssh2_pkt_send(ssh, s->pktout);
45068b27 6812 } else {
6813 /*
6814 * If there are prompts remaining, we set
6815 * `gotit' so that we won't attempt to get
6816 * another packet. Then we go back round the
6817 * loop and will end up retrieving another
6818 * prompt out of the existing packet. Funky or
6819 * what?
6820 */
51470298 6821 s->gotit = TRUE;
45068b27 6822 }
51470298 6823 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
1408a877 6824 } else {
51470298 6825 c_write_str(ssh, "No supported authentication methods"
6826 " left to try!\r\n");
6827 logevent("No supported authentications offered."
6828 " Disconnecting");
ff3187f6 6829 s->pktout = ssh2_pkt_init(SSH2_MSG_DISCONNECT);
6830 ssh2_pkt_adduint32(s->pktout, SSH2_DISCONNECT_BY_APPLICATION);
6831 ssh2_pkt_addstring(s->pktout, "No supported authentication"
51470298 6832 " methods available");
ff3187f6 6833 ssh2_pkt_addstring(s->pktout, "en"); /* language tag */
590f6a5f 6834 ssh2_pkt_send_noqueue(ssh, s->pktout);
ac934965 6835 ssh->close_expected = TRUE;
3bb2f322 6836 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 6837 crStopV;
65a22376 6838 }
65a22376 6839 }
51470298 6840 } while (!s->we_are_in);
7cca0d81 6841
6842 /*
6843 * Now we're authenticated for the connection protocol. The
6844 * connection protocol will automatically have started at this
6845 * point; there's no need to send SERVICE_REQUEST.
6846 */
6847
0ed48730 6848 ssh->channels = newtree234(ssh_channelcmp);
6849
7cca0d81 6850 /*
b09eaa88 6851 * Set up handlers for some connection protocol messages, so we
6852 * don't have to handle them repeatedly in this coroutine.
6853 */
6854 ssh->packet_dispatch[SSH2_MSG_CHANNEL_WINDOW_ADJUST] =
6855 ssh2_msg_channel_window_adjust;
51df0ab5 6856 ssh->packet_dispatch[SSH2_MSG_GLOBAL_REQUEST] =
6857 ssh2_msg_global_request;
b09eaa88 6858
6859 /*
0ed48730 6860 * Create the main session channel.
7cca0d81 6861 */
0ed48730 6862 if (!ssh->cfg.ssh_no_shell) {
6863 ssh->mainchan = snew(struct ssh_channel);
6864 ssh->mainchan->ssh = ssh;
6865 ssh->mainchan->localid = alloc_channel_id(ssh);
ff3187f6 6866 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
6867 ssh2_pkt_addstring(s->pktout, "session");
6868 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->localid);
0ed48730 6869 ssh->mainchan->v.v2.locwindow = OUR_V2_WINSIZE;
ff3187f6 6870 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->v.v2.locwindow);/* our window size */
6871 ssh2_pkt_adduint32(s->pktout, 0x4000UL); /* our max pkt size */
6872 ssh2_pkt_send(ssh, s->pktout);
6873 crWaitUntilV(pktin);
6874 if (pktin->type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
0ed48730 6875 bombout(("Server refused to open a session"));
6876 crStopV;
6877 /* FIXME: error data comes back in FAILURE packet */
6878 }
ff3187f6 6879 if (ssh_pkt_getuint32(pktin) != ssh->mainchan->localid) {
0ed48730 6880 bombout(("Server's channel confirmation cited wrong channel"));
6881 crStopV;
6882 }
ff3187f6 6883 ssh->mainchan->remoteid = ssh_pkt_getuint32(pktin);
0ed48730 6884 ssh->mainchan->type = CHAN_MAINSESSION;
6885 ssh->mainchan->closes = 0;
ff3187f6 6886 ssh->mainchan->v.v2.remwindow = ssh_pkt_getuint32(pktin);
6887 ssh->mainchan->v.v2.remmaxpkt = ssh_pkt_getuint32(pktin);
0ed48730 6888 bufchain_init(&ssh->mainchan->v.v2.outbuffer);
6889 add234(ssh->channels, ssh->mainchan);
62638676 6890 update_specials_menu(ssh->frontend);
0ed48730 6891 logevent("Opened channel for session");
6892 } else
6893 ssh->mainchan = NULL;
7cca0d81 6894
6895 /*
51df0ab5 6896 * Now we have a channel, make dispatch table entries for
6897 * general channel-based messages.
6898 */
6899 ssh->packet_dispatch[SSH2_MSG_CHANNEL_DATA] =
6900 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EXTENDED_DATA] =
6901 ssh2_msg_channel_data;
6902 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EOF] = ssh2_msg_channel_eof;
6903 ssh->packet_dispatch[SSH2_MSG_CHANNEL_CLOSE] = ssh2_msg_channel_close;
6904 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION] =
6905 ssh2_msg_channel_open_confirmation;
6906 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_FAILURE] =
6907 ssh2_msg_channel_open_failure;
6908 ssh->packet_dispatch[SSH2_MSG_CHANNEL_REQUEST] =
6909 ssh2_msg_channel_request;
6910 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN] =
6911 ssh2_msg_channel_open;
6912
6913 /*
783415f8 6914 * Potentially enable X11 forwarding.
6915 */
0ed48730 6916 if (ssh->mainchan && ssh->cfg.x11_forward) {
32874aea 6917 char proto[20], data[64];
6918 logevent("Requesting X11 forwarding");
302121de 6919 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
86916870 6920 data, sizeof(data), ssh->cfg.x11_auth);
6921 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
ff3187f6 6922 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
6923 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
6924 ssh2_pkt_addstring(s->pktout, "x11-req");
6925 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
6926 ssh2_pkt_addbool(s->pktout, 0); /* many connections */
6927 ssh2_pkt_addstring(s->pktout, proto);
6928 ssh2_pkt_addstring(s->pktout, data);
6929 ssh2_pkt_adduint32(s->pktout, x11_get_screen_number(ssh->cfg.x11_display));
6930 ssh2_pkt_send(ssh, s->pktout);
32874aea 6931
b09eaa88 6932 crWaitUntilV(pktin);
32874aea 6933
ff3187f6 6934 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
6935 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 6936 bombout(("Unexpected response to X11 forwarding request:"
ff3187f6 6937 " packet type %d", pktin->type));
7ffdbc1a 6938 crStopV;
32874aea 6939 }
6940 logevent("X11 forwarding refused");
6941 } else {
6942 logevent("X11 forwarding enabled");
51470298 6943 ssh->X11_fwd_enabled = TRUE;
32874aea 6944 }
783415f8 6945 }
6946
6947 /*
bc240b21 6948 * Enable port forwardings.
6949 */
06fadff5 6950 ssh_setup_portfwd(ssh, &ssh->cfg);
bc240b21 6951
6952 /*
36c2a3e9 6953 * Potentially enable agent forwarding.
6954 */
0ed48730 6955 if (ssh->mainchan && ssh->cfg.agentfwd && agent_exists()) {
32874aea 6956 logevent("Requesting OpenSSH-style agent forwarding");
ff3187f6 6957 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
6958 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
6959 ssh2_pkt_addstring(s->pktout, "auth-agent-req@openssh.com");
6960 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
6961 ssh2_pkt_send(ssh, s->pktout);
32874aea 6962
b09eaa88 6963 crWaitUntilV(pktin);
32874aea 6964
ff3187f6 6965 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
6966 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 6967 bombout(("Unexpected response to agent forwarding request:"
ff3187f6 6968 " packet type %d", pktin->type));
7ffdbc1a 6969 crStopV;
32874aea 6970 }
6971 logevent("Agent forwarding refused");
6972 } else {
6973 logevent("Agent forwarding enabled");
51470298 6974 ssh->agentfwd_enabled = TRUE;
32874aea 6975 }
36c2a3e9 6976 }
6977
6978 /*
7cca0d81 6979 * Now allocate a pty for the session.
6980 */
0ed48730 6981 if (ssh->mainchan && !ssh->cfg.nopty) {
a5dd8467 6982 /* Unpick the terminal-speed string. */
6983 /* XXX perhaps we should allow no speeds to be sent. */
db219738 6984 ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
6985 sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
a5dd8467 6986 /* Build the pty request. */
ff3187f6 6987 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
6988 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid); /* recipient channel */
6989 ssh2_pkt_addstring(s->pktout, "pty-req");
6990 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
6991 ssh2_pkt_addstring(s->pktout, ssh->cfg.termtype);
6992 ssh2_pkt_adduint32(s->pktout, ssh->term_width);
6993 ssh2_pkt_adduint32(s->pktout, ssh->term_height);
6994 ssh2_pkt_adduint32(s->pktout, 0); /* pixel width */
6995 ssh2_pkt_adduint32(s->pktout, 0); /* pixel height */
6996 ssh2_pkt_addstring_start(s->pktout);
6997 ssh2_pkt_addbyte(s->pktout, 128); /* TTY_OP_ISPEED */
6998 ssh2_pkt_adduint32(s->pktout, ssh->ispeed);
6999 ssh2_pkt_addbyte(s->pktout, 129); /* TTY_OP_OSPEED */
7000 ssh2_pkt_adduint32(s->pktout, ssh->ospeed);
7001 ssh2_pkt_addstring_data(s->pktout, "\0", 1); /* TTY_OP_END */
7002 ssh2_pkt_send(ssh, s->pktout);
51470298 7003 ssh->state = SSH_STATE_INTERMED;
32874aea 7004
b09eaa88 7005 crWaitUntilV(pktin);
32874aea 7006
ff3187f6 7007 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
7008 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 7009 bombout(("Unexpected response to pty request:"
ff3187f6 7010 " packet type %d", pktin->type));
7ffdbc1a 7011 crStopV;
32874aea 7012 }
51470298 7013 c_write_str(ssh, "Server refused to allocate pty\r\n");
7014 ssh->editing = ssh->echoing = 1;
32874aea 7015 } else {
a5dd8467 7016 logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
db219738 7017 ssh->ospeed, ssh->ispeed);
32874aea 7018 }
0965bee0 7019 } else {
51470298 7020 ssh->editing = ssh->echoing = 1;
7cca0d81 7021 }
7022
7023 /*
73feed4f 7024 * Send environment variables.
7025 *
7026 * Simplest thing here is to send all the requests at once, and
7027 * then wait for a whole bunch of successes or failures.
7028 */
7029 if (ssh->mainchan && *ssh->cfg.environmt) {
7030 char *e = ssh->cfg.environmt;
7031 char *var, *varend, *val;
7032
7033 s->num_env = 0;
7034
7035 while (*e) {
7036 var = e;
7037 while (*e && *e != '\t') e++;
7038 varend = e;
7039 if (*e == '\t') e++;
7040 val = e;
7041 while (*e) e++;
7042 e++;
7043
ff3187f6 7044 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7045 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid);
7046 ssh2_pkt_addstring(s->pktout, "env");
7047 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7048 ssh2_pkt_addstring_start(s->pktout);
7049 ssh2_pkt_addstring_data(s->pktout, var, varend-var);
7050 ssh2_pkt_addstring(s->pktout, val);
7051 ssh2_pkt_send(ssh, s->pktout);
73feed4f 7052
7053 s->num_env++;
7054 }
7055
7056 logeventf(ssh, "Sent %d environment variables", s->num_env);
7057
7058 s->env_ok = 0;
7059 s->env_left = s->num_env;
7060
7061 while (s->env_left > 0) {
b09eaa88 7062 crWaitUntilV(pktin);
73feed4f 7063
ff3187f6 7064 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
7065 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
73feed4f 7066 bombout(("Unexpected response to environment request:"
ff3187f6 7067 " packet type %d", pktin->type));
73feed4f 7068 crStopV;
7069 }
7070 } else {
7071 s->env_ok++;
7072 }
7073
7074 s->env_left--;
7075 }
7076
7077 if (s->env_ok == s->num_env) {
7078 logevent("All environment variables successfully set");
7079 } else if (s->env_ok == 0) {
7080 logevent("All environment variables refused");
7081 c_write_str(ssh, "Server refused to set environment variables\r\n");
7082 } else {
7083 logeventf(ssh, "%d environment variables refused",
7084 s->num_env - s->env_ok);
7085 c_write_str(ssh, "Server refused to set all environment variables\r\n");
7086 }
7087 }
7088
7089 /*
fd5e5847 7090 * Start a shell or a remote command. We may have to attempt
7091 * this twice if the config data has provided a second choice
7092 * of command.
7cca0d81 7093 */
0ed48730 7094 if (ssh->mainchan) while (1) {
fd5e5847 7095 int subsys;
7096 char *cmd;
7097
51470298 7098 if (ssh->fallback_cmd) {
86916870 7099 subsys = ssh->cfg.ssh_subsys2;
7100 cmd = ssh->cfg.remote_cmd_ptr2;
fd5e5847 7101 } else {
86916870 7102 subsys = ssh->cfg.ssh_subsys;
7103 cmd = ssh->cfg.remote_cmd_ptr;
fd5e5847 7104 }
7105
ff3187f6 7106 s->pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7107 ssh2_pkt_adduint32(s->pktout, ssh->mainchan->remoteid); /* recipient channel */
fd5e5847 7108 if (subsys) {
ff3187f6 7109 ssh2_pkt_addstring(s->pktout, "subsystem");
7110 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7111 ssh2_pkt_addstring(s->pktout, cmd);
fd5e5847 7112 } else if (*cmd) {
ff3187f6 7113 ssh2_pkt_addstring(s->pktout, "exec");
7114 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
7115 ssh2_pkt_addstring(s->pktout, cmd);
fd5e5847 7116 } else {
ff3187f6 7117 ssh2_pkt_addstring(s->pktout, "shell");
7118 ssh2_pkt_addbool(s->pktout, 1); /* want reply */
32874aea 7119 }
ff3187f6 7120 ssh2_pkt_send(ssh, s->pktout);
b09eaa88 7121
7122 crWaitUntilV(pktin);
7123
ff3187f6 7124 if (pktin->type != SSH2_MSG_CHANNEL_SUCCESS) {
7125 if (pktin->type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 7126 bombout(("Unexpected response to shell/command request:"
ff3187f6 7127 " packet type %d", pktin->type));
7ffdbc1a 7128 crStopV;
fd5e5847 7129 }
7130 /*
7131 * We failed to start the command. If this is the
7132 * fallback command, we really are finished; if it's
7133 * not, and if the fallback command exists, try falling
7134 * back to it before complaining.
7135 */
86916870 7136 if (!ssh->fallback_cmd && ssh->cfg.remote_cmd_ptr2 != NULL) {
fd5e5847 7137 logevent("Primary command failed; attempting fallback");
51470298 7138 ssh->fallback_cmd = TRUE;
fd5e5847 7139 continue;
7140 }
6b5cf8b4 7141 bombout(("Server refused to start a shell/command"));
7ffdbc1a 7142 crStopV;
fd5e5847 7143 } else {
7144 logevent("Started a shell/command");
32874aea 7145 }
fd5e5847 7146 break;
7cca0d81 7147 }
7148
51470298 7149 ssh->state = SSH_STATE_SESSION;
7150 if (ssh->size_needed)
7151 ssh_size(ssh, ssh->term_width, ssh->term_height);
7152 if (ssh->eof_needed)
7153 ssh_special(ssh, TS_EOF);
6e48c3fe 7154
7cca0d81 7155 /*
7156 * Transfer data!
7157 */
b9d7bcad 7158 if (ssh->ldisc)
7159 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
0ed48730 7160 if (ssh->mainchan)
7161 ssh->send_ok = 1;
7cca0d81 7162 while (1) {
e5574168 7163 crReturnV;
51470298 7164 s->try_send = FALSE;
ff3187f6 7165 if (pktin) {
2b7540a7 7166
51df0ab5 7167 /*
7168 * _All_ the connection-layer packets we expect to
7169 * receive are now handled by the dispatch table.
7170 * Anything that reaches here must be bogus.
7171 */
32874aea 7172
51df0ab5 7173 bombout(("Strange packet received: type %d", pktin->type));
7174 crStopV;
0ed48730 7175 } else if (ssh->mainchan) {
32874aea 7176 /*
7177 * We have spare data. Add it to the channel buffer.
7178 */
d8baa528 7179 ssh2_add_channel_data(ssh->mainchan, (char *)in, inlen);
51470298 7180 s->try_send = TRUE;
32874aea 7181 }
51470298 7182 if (s->try_send) {
32874aea 7183 int i;
7184 struct ssh_channel *c;
7185 /*
7186 * Try to send data on all channels if we can.
7187 */
51470298 7188 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
a6253970 7189 int bufsize;
7190 if (c->closes)
7191 continue; /* don't send on closing channels */
7192 bufsize = ssh2_try_send(c);
5471d09a 7193 if (bufsize == 0) {
7194 switch (c->type) {
7195 case CHAN_MAINSESSION:
7196 /* stdin need not receive an unthrottle
7197 * notification since it will be polled */
7198 break;
7199 case CHAN_X11:
7200 x11_unthrottle(c->u.x11.s);
7201 break;
7202 case CHAN_AGENT:
7203 /* agent sockets are request/response and need no
7204 * buffer management */
7205 break;
7206 case CHAN_SOCKDATA:
7207 pfd_unthrottle(c->u.pfd.s);
7208 break;
7209 }
7210 }
7211 }
7cca0d81 7212 }
e5574168 7213 }
7214
7215 crFinishV;
7216}
7217
7218/*
b09eaa88 7219 * Handlers for SSH2 messages that might arrive at any moment.
7220 */
7221void ssh2_msg_disconnect(Ssh ssh, struct Packet *pktin)
7222{
7223 /* log reason code in disconnect message */
7224 char *buf, *msg;
7225 int nowlen, reason, msglen;
7226
7227 reason = ssh_pkt_getuint32(pktin);
7228 ssh_pkt_getstring(pktin, &msg, &msglen);
7229
7230 if (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) {
7231 buf = dupprintf("Received disconnect message (%s)",
7232 ssh2_disconnect_reasons[reason]);
7233 } else {
7234 buf = dupprintf("Received disconnect message (unknown"
7235 " type %d)", reason);
7236 }
7237 logevent(buf);
7238 sfree(buf);
7239 buf = dupprintf("Disconnection message text: %n%.*s",
7240 &nowlen, msglen, msg);
7241 logevent(buf);
7242 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
7243 reason,
7244 (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) ?
7245 ssh2_disconnect_reasons[reason] : "unknown",
7246 buf+nowlen));
7247 sfree(buf);
7248}
7249
7250void ssh2_msg_debug(Ssh ssh, struct Packet *pktin)
7251{
7252 /* log the debug message */
7253 char *buf, *msg;
7254 int msglen;
7255 int always_display;
7256
7257 /* XXX maybe we should actually take notice of this */
7258 always_display = ssh2_pkt_getbool(pktin);
7259 ssh_pkt_getstring(pktin, &msg, &msglen);
7260
7261 buf = dupprintf("Remote debug message: %.*s", msglen, msg);
7262 logevent(buf);
7263 sfree(buf);
7264}
7265
7266void ssh2_msg_something_unimplemented(Ssh ssh, struct Packet *pktin)
7267{
7268 struct Packet *pktout;
7269 pktout = ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED);
7270 ssh2_pkt_adduint32(pktout, pktin->sequence);
7271 /*
7272 * UNIMPLEMENTED messages MUST appear in the same order as the
7273 * messages they respond to. Hence, never queue them.
7274 */
7275 ssh2_pkt_send_noqueue(ssh, pktout);
7276}
7277
7278/*
7cca0d81 7279 * Handle the top-level SSH2 protocol.
7280 */
b09eaa88 7281static void ssh2_protocol_setup(Ssh ssh)
7282{
7283 int i;
7284
7285 /*
7286 * Most messages cause SSH2_MSG_UNIMPLEMENTED.
7287 */
7288 for (i = 0; i < 256; i++)
7289 ssh->packet_dispatch[i] = ssh2_msg_something_unimplemented;
7290
7291 /*
7292 * Any message we actually understand, we set to NULL so that
7293 * the coroutines will get it.
7294 */
7295 ssh->packet_dispatch[SSH2_MSG_UNIMPLEMENTED] = NULL;
7296 ssh->packet_dispatch[SSH2_MSG_SERVICE_REQUEST] = NULL;
7297 ssh->packet_dispatch[SSH2_MSG_SERVICE_ACCEPT] = NULL;
7298 ssh->packet_dispatch[SSH2_MSG_KEXINIT] = NULL;
7299 ssh->packet_dispatch[SSH2_MSG_NEWKEYS] = NULL;
7300 ssh->packet_dispatch[SSH2_MSG_KEXDH_INIT] = NULL;
7301 ssh->packet_dispatch[SSH2_MSG_KEXDH_REPLY] = NULL;
7302 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REQUEST] = NULL; duplicate case value */
7303 /* ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_GROUP] = NULL; duplicate case value */
7304 ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_INIT] = NULL;
7305 ssh->packet_dispatch[SSH2_MSG_KEX_DH_GEX_REPLY] = NULL;
7306 ssh->packet_dispatch[SSH2_MSG_USERAUTH_REQUEST] = NULL;
7307 ssh->packet_dispatch[SSH2_MSG_USERAUTH_FAILURE] = NULL;
7308 ssh->packet_dispatch[SSH2_MSG_USERAUTH_SUCCESS] = NULL;
7309 ssh->packet_dispatch[SSH2_MSG_USERAUTH_BANNER] = NULL;
7310 ssh->packet_dispatch[SSH2_MSG_USERAUTH_PK_OK] = NULL;
7311 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ] = NULL; duplicate case value */
7312 /* ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_REQUEST] = NULL; duplicate case value */
7313 ssh->packet_dispatch[SSH2_MSG_USERAUTH_INFO_RESPONSE] = NULL;
7314 ssh->packet_dispatch[SSH2_MSG_GLOBAL_REQUEST] = NULL;
7315 ssh->packet_dispatch[SSH2_MSG_REQUEST_SUCCESS] = NULL;
7316 ssh->packet_dispatch[SSH2_MSG_REQUEST_FAILURE] = NULL;
7317 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN] = NULL;
7318 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_CONFIRMATION] = NULL;
7319 ssh->packet_dispatch[SSH2_MSG_CHANNEL_OPEN_FAILURE] = NULL;
7320 ssh->packet_dispatch[SSH2_MSG_CHANNEL_WINDOW_ADJUST] = NULL;
7321 ssh->packet_dispatch[SSH2_MSG_CHANNEL_DATA] = NULL;
7322 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EXTENDED_DATA] = NULL;
7323 ssh->packet_dispatch[SSH2_MSG_CHANNEL_EOF] = NULL;
7324 ssh->packet_dispatch[SSH2_MSG_CHANNEL_CLOSE] = NULL;
7325 ssh->packet_dispatch[SSH2_MSG_CHANNEL_REQUEST] = NULL;
7326 ssh->packet_dispatch[SSH2_MSG_CHANNEL_SUCCESS] = NULL;
7327 ssh->packet_dispatch[SSH2_MSG_CHANNEL_FAILURE] = NULL;
7328
7329 /*
7330 * These special message types we install handlers for.
7331 */
7332 ssh->packet_dispatch[SSH2_MSG_DISCONNECT] = ssh2_msg_disconnect;
7333 ssh->packet_dispatch[SSH2_MSG_IGNORE] = ssh_msg_ignore; /* shared with ssh1 */
7334 ssh->packet_dispatch[SSH2_MSG_DEBUG] = ssh2_msg_debug;
7335}
7336
9442dd57 7337static void ssh2_timer(void *ctx, long now)
7338{
7339 Ssh ssh = (Ssh)ctx;
7340
e6c1536e 7341 if (!ssh->kex_in_progress && ssh->cfg.ssh_rekey_time != 0 &&
9442dd57 7342 now - ssh->next_rekey >= 0) {
f382c87d 7343 do_ssh2_transport(ssh, "timeout", -1, NULL);
9442dd57 7344 }
7345}
7346
ff3187f6 7347static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen,
7348 struct Packet *pktin)
7cca0d81 7349{
b09eaa88 7350 if (ssh->state == SSH_STATE_CLOSED)
7351 return;
7352
9442dd57 7353 if (pktin) {
7354 ssh->incoming_data_size += pktin->encrypted_len;
7355 if (!ssh->kex_in_progress &&
d57f70af 7356 ssh->max_data_size != 0 &&
7357 ssh->incoming_data_size > ssh->max_data_size)
f382c87d 7358 do_ssh2_transport(ssh, "too much data received", -1, NULL);
9442dd57 7359 }
7360
b09eaa88 7361 if (pktin && ssh->packet_dispatch[pktin->type]) {
7362 ssh->packet_dispatch[pktin->type](ssh, pktin);
32874aea 7363 return;
b09eaa88 7364 }
7365
7366 if (!ssh->protocol_initial_phase_done ||
7367 (pktin && pktin->type >= 20 && pktin->type < 50)) {
7368 if (do_ssh2_transport(ssh, in, inlen, pktin) &&
7369 !ssh->protocol_initial_phase_done) {
7370 ssh->protocol_initial_phase_done = TRUE;
7371 /*
7372 * Allow authconn to initialise itself.
7373 */
7374 do_ssh2_authconn(ssh, NULL, 0, NULL);
7375 }
7376 } else {
7377 do_ssh2_authconn(ssh, in, inlen, pktin);
7378 }
7cca0d81 7379}
7380
7381/*
8df7a775 7382 * Called to set up the connection.
374330e2 7383 *
7384 * Returns an error message, or NULL on success.
374330e2 7385 */
cbe2d68f 7386static const char *ssh_init(void *frontend_handle, void **backend_handle,
7387 Config *cfg,
79bf227b 7388 char *host, int port, char **realhost, int nodelay,
7389 int keepalive)
32874aea 7390{
cbe2d68f 7391 const char *p;
51470298 7392 Ssh ssh;
7393
3d88e64d 7394 ssh = snew(struct ssh_tag);
86916870 7395 ssh->cfg = *cfg; /* STRUCTURE COPY */
125105d1 7396 ssh->version = 0; /* when not ready yet */
51470298 7397 ssh->s = NULL;
7398 ssh->cipher = NULL;
371e569c 7399 ssh->v1_cipher_ctx = NULL;
0183b242 7400 ssh->crcda_ctx = NULL;
51470298 7401 ssh->cscipher = NULL;
371e569c 7402 ssh->cs_cipher_ctx = NULL;
51470298 7403 ssh->sccipher = NULL;
371e569c 7404 ssh->sc_cipher_ctx = NULL;
51470298 7405 ssh->csmac = NULL;
a8327734 7406 ssh->cs_mac_ctx = NULL;
51470298 7407 ssh->scmac = NULL;
e0e1a00d 7408 ssh->sc_mac_ctx = NULL;
51470298 7409 ssh->cscomp = NULL;
5366aed8 7410 ssh->cs_comp_ctx = NULL;
51470298 7411 ssh->sccomp = NULL;
5366aed8 7412 ssh->sc_comp_ctx = NULL;
51470298 7413 ssh->kex = NULL;
389aa499 7414 ssh->kex_ctx = NULL;
51470298 7415 ssh->hostkey = NULL;
7416 ssh->exitcode = -1;
ac934965 7417 ssh->close_expected = FALSE;
51470298 7418 ssh->state = SSH_STATE_PREPACKET;
7419 ssh->size_needed = FALSE;
7420 ssh->eof_needed = FALSE;
b9d7bcad 7421 ssh->ldisc = NULL;
a8327734 7422 ssh->logctx = NULL;
51470298 7423 ssh->deferred_send_data = NULL;
7424 ssh->deferred_len = 0;
7425 ssh->deferred_size = 0;
7426 ssh->fallback_cmd = 0;
7427 ssh->pkt_ctx = 0;
302121de 7428 ssh->x11auth = NULL;
be738459 7429 ssh->v1_compressing = FALSE;
51470298 7430 ssh->v2_outgoing_sequence = 0;
7431 ssh->ssh1_rdpkt_crstate = 0;
7432 ssh->ssh2_rdpkt_crstate = 0;
7433 ssh->do_ssh_init_crstate = 0;
7434 ssh->ssh_gotdata_crstate = 0;
b09eaa88 7435 ssh->do_ssh1_connection_crstate = 0;
51470298 7436 ssh->do_ssh1_login_crstate = 0;
7437 ssh->do_ssh2_transport_crstate = 0;
7438 ssh->do_ssh2_authconn_crstate = 0;
7439 ssh->do_ssh_init_state = NULL;
7440 ssh->do_ssh1_login_state = NULL;
7441 ssh->do_ssh2_transport_state = NULL;
7442 ssh->do_ssh2_authconn_state = NULL;
6571dbfd 7443 ssh->mainchan = NULL;
968d2d92 7444 ssh->throttled_all = 0;
7445 ssh->v1_stdout_throttling = 0;
590f6a5f 7446 ssh->queue = NULL;
7447 ssh->queuelen = ssh->queuesize = 0;
7448 ssh->queueing = FALSE;
06fadff5 7449 ssh->qhead = ssh->qtail = NULL;
e13bba36 7450 ssh->deferred_rekey_reason = NULL;
51470298 7451
7452 *backend_handle = ssh;
32874aea 7453
8f203108 7454#ifdef MSCRYPTOAPI
32874aea 7455 if (crypto_startup() == 0)
8f203108 7456 return "Microsoft high encryption pack not installed!";
7457#endif
374330e2 7458
51470298 7459 ssh->frontend = frontend_handle;
86916870 7460 ssh->term_width = ssh->cfg.width;
7461 ssh->term_height = ssh->cfg.height;
887035a5 7462
fabd1805 7463 ssh->channels = NULL;
7464 ssh->rportfwds = NULL;
f47a5ffb 7465 ssh->portfwds = NULL;
fabd1805 7466
51470298 7467 ssh->send_ok = 0;
7468 ssh->editing = 0;
7469 ssh->echoing = 0;
7470 ssh->v1_throttle_count = 0;
7471 ssh->overall_bufsize = 0;
7472 ssh->fallback_cmd = 0;
8df7a775 7473
3648d4c5 7474 ssh->protocol = NULL;
7475
b09eaa88 7476 ssh->protocol_initial_phase_done = FALSE;
7477
39934deb 7478 ssh->pinger = NULL;
7479
9442dd57 7480 ssh->incoming_data_size = ssh->outgoing_data_size =
7481 ssh->deferred_data_size = 0L;
d57f70af 7482 ssh->max_data_size = parse_blocksize(ssh->cfg.ssh_rekey_data);
9442dd57 7483 ssh->kex_in_progress = FALSE;
7484
79bf227b 7485 p = connect_to_host(ssh, host, port, realhost, nodelay, keepalive);
fb09bf1c 7486 if (p != NULL)
7487 return p;
374330e2 7488
5d17ccfc 7489 random_ref();
7490
374330e2 7491 return NULL;
7492}
7493
fabd1805 7494static void ssh_free(void *handle)
7495{
7496 Ssh ssh = (Ssh) handle;
7497 struct ssh_channel *c;
7498 struct ssh_rportfwd *pf;
7499
7500 if (ssh->v1_cipher_ctx)
7501 ssh->cipher->free_context(ssh->v1_cipher_ctx);
7502 if (ssh->cs_cipher_ctx)
7503 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
7504 if (ssh->sc_cipher_ctx)
7505 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
7506 if (ssh->cs_mac_ctx)
7507 ssh->csmac->free_context(ssh->cs_mac_ctx);
7508 if (ssh->sc_mac_ctx)
7509 ssh->scmac->free_context(ssh->sc_mac_ctx);
29b1d0b3 7510 if (ssh->cs_comp_ctx) {
7511 if (ssh->cscomp)
7512 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
7513 else
7514 zlib_compress_cleanup(ssh->cs_comp_ctx);
7515 }
7516 if (ssh->sc_comp_ctx) {
7517 if (ssh->sccomp)
7518 ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
7519 else
7520 zlib_decompress_cleanup(ssh->sc_comp_ctx);
7521 }
fabd1805 7522 if (ssh->kex_ctx)
7523 dh_cleanup(ssh->kex_ctx);
7524 sfree(ssh->savedhost);
7525
590f6a5f 7526 while (ssh->queuelen-- > 0)
7527 ssh_free_packet(ssh->queue[ssh->queuelen]);
7528 sfree(ssh->queue);
7529
06fadff5 7530 while (ssh->qhead) {
7531 struct queued_handler *qh = ssh->qhead;
7532 ssh->qhead = qh->next;
7533 sfree(ssh->qhead);
7534 }
7535 ssh->qhead = ssh->qtail = NULL;
7536
fabd1805 7537 if (ssh->channels) {
7538 while ((c = delpos234(ssh->channels, 0)) != NULL) {
7539 switch (c->type) {
7540 case CHAN_X11:
7541 if (c->u.x11.s != NULL)
7542 x11_close(c->u.x11.s);
7543 break;
7544 case CHAN_SOCKDATA:
7545 if (c->u.pfd.s != NULL)
7546 pfd_close(c->u.pfd.s);
7547 break;
7548 }
7549 sfree(c);
7550 }
7551 freetree234(ssh->channels);
cdb52705 7552 ssh->channels = NULL;
fabd1805 7553 }
7554
7555 if (ssh->rportfwds) {
7556 while ((pf = delpos234(ssh->rportfwds, 0)) != NULL)
7557 sfree(pf);
7558 freetree234(ssh->rportfwds);
cdb52705 7559 ssh->rportfwds = NULL;
fabd1805 7560 }
7561 sfree(ssh->deferred_send_data);
7562 if (ssh->x11auth)
7563 x11_free_auth(ssh->x11auth);
7564 sfree(ssh->do_ssh_init_state);
7565 sfree(ssh->do_ssh1_login_state);
7566 sfree(ssh->do_ssh2_transport_state);
7567 sfree(ssh->do_ssh2_authconn_state);
679539d7 7568 if (ssh->crcda_ctx) {
7569 crcda_free_context(ssh->crcda_ctx);
7570 ssh->crcda_ctx = NULL;
7571 }
fabd1805 7572 if (ssh->s)
ac934965 7573 ssh_do_close(ssh, TRUE);
9442dd57 7574 expire_timer_context(ssh);
39934deb 7575 if (ssh->pinger)
7576 pinger_free(ssh->pinger);
ee50e8b6 7577 sfree(ssh);
5d17ccfc 7578
7579 random_unref();
fabd1805 7580}
7581
374330e2 7582/*
86916870 7583 * Reconfigure the SSH backend.
86916870 7584 */
7585static void ssh_reconfig(void *handle, Config *cfg)
7586{
7587 Ssh ssh = (Ssh) handle;
e13bba36 7588 char *rekeying = NULL, rekey_mandatory = FALSE;
e6c1536e 7589 unsigned long old_max_data_size;
7590
39934deb 7591 pinger_reconfig(ssh->pinger, &ssh->cfg, cfg);
fda2feb1 7592 ssh_setup_portfwd(ssh, cfg);
e6c1536e 7593
7594 if (ssh->cfg.ssh_rekey_time != cfg->ssh_rekey_time &&
7595 cfg->ssh_rekey_time != 0) {
7596 long new_next = ssh->last_rekey + cfg->ssh_rekey_time*60*TICKSPERSEC;
7597 long now = GETTICKCOUNT();
7598
7599 if (new_next - now < 0) {
f382c87d 7600 rekeying = "timeout shortened";
e6c1536e 7601 } else {
7602 ssh->next_rekey = schedule_timer(new_next - now, ssh2_timer, ssh);
7603 }
7604 }
7605
7606 old_max_data_size = ssh->max_data_size;
7607 ssh->max_data_size = parse_blocksize(cfg->ssh_rekey_data);
7608 if (old_max_data_size != ssh->max_data_size &&
7609 ssh->max_data_size != 0) {
7610 if (ssh->outgoing_data_size > ssh->max_data_size ||
7611 ssh->incoming_data_size > ssh->max_data_size)
f382c87d 7612 rekeying = "data limit lowered";
e6c1536e 7613 }
7614
e13bba36 7615 if (ssh->cfg.compression != cfg->compression) {
f382c87d 7616 rekeying = "compression setting changed";
e13bba36 7617 rekey_mandatory = TRUE;
7618 }
7619
7620 if (ssh->cfg.ssh2_des_cbc != cfg->ssh2_des_cbc ||
7621 memcmp(ssh->cfg.ssh_cipherlist, cfg->ssh_cipherlist,
7622 sizeof(ssh->cfg.ssh_cipherlist))) {
f382c87d 7623 rekeying = "cipher settings changed";
e13bba36 7624 rekey_mandatory = TRUE;
e6c1536e 7625 }
7626
86916870 7627 ssh->cfg = *cfg; /* STRUCTURE COPY */
e13bba36 7628
7629 if (rekeying) {
7630 if (!ssh->kex_in_progress) {
7631 do_ssh2_transport(ssh, rekeying, -1, NULL);
7632 } else if (rekey_mandatory) {
7633 ssh->deferred_rekey_reason = rekeying;
7634 }
7635 }
86916870 7636}
7637
7638/*
374330e2 7639 * Called to send data down the Telnet connection.
7640 */
51470298 7641static int ssh_send(void *handle, char *buf, int len)
32874aea 7642{
51470298 7643 Ssh ssh = (Ssh) handle;
7644
7645 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
5471d09a 7646 return 0;
374330e2 7647
d8baa528 7648 ssh->protocol(ssh, (unsigned char *)buf, len, 0);
5471d09a 7649
51470298 7650 return ssh_sendbuffer(ssh);
5471d09a 7651}
7652
7653/*
7654 * Called to query the current amount of buffered stdin data.
7655 */
51470298 7656static int ssh_sendbuffer(void *handle)
5471d09a 7657{
51470298 7658 Ssh ssh = (Ssh) handle;
5471d09a 7659 int override_value;
7660
51470298 7661 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
5471d09a 7662 return 0;
7663
7664 /*
7665 * If the SSH socket itself has backed up, add the total backup
7666 * size on that to any individual buffer on the stdin channel.
7667 */
7668 override_value = 0;
51470298 7669 if (ssh->throttled_all)
7670 override_value = ssh->overall_bufsize;
5471d09a 7671
51470298 7672 if (ssh->version == 1) {
5471d09a 7673 return override_value;
51470298 7674 } else if (ssh->version == 2) {
7675 if (!ssh->mainchan || ssh->mainchan->closes > 0)
5471d09a 7676 return override_value;
7677 else
51470298 7678 return (override_value +
7679 bufchain_size(&ssh->mainchan->v.v2.outbuffer));
5471d09a 7680 }
7681
7682 return 0;
374330e2 7683}
7684
7685/*
6e48c3fe 7686 * Called to set the size of the window from SSH's POV.
374330e2 7687 */
51470298 7688static void ssh_size(void *handle, int width, int height)
32874aea 7689{
51470298 7690 Ssh ssh = (Ssh) handle;
ff3187f6 7691 struct Packet *pktout;
51470298 7692
7693 ssh->term_width = width;
7694 ssh->term_height = height;
f278d6f8 7695
51470298 7696 switch (ssh->state) {
374330e2 7697 case SSH_STATE_BEFORE_SIZE:
3687d221 7698 case SSH_STATE_PREPACKET:
21248260 7699 case SSH_STATE_CLOSED:
374330e2 7700 break; /* do nothing */
7701 case SSH_STATE_INTERMED:
51470298 7702 ssh->size_needed = TRUE; /* buffer for later */
374330e2 7703 break;
7704 case SSH_STATE_SESSION:
86916870 7705 if (!ssh->cfg.nopty) {
51470298 7706 if (ssh->version == 1) {
7707 send_packet(ssh, SSH1_CMSG_WINDOW_SIZE,
7708 PKT_INT, ssh->term_height,
7709 PKT_INT, ssh->term_width,
32874aea 7710 PKT_INT, 0, PKT_INT, 0, PKT_END);
0ed48730 7711 } else if (ssh->mainchan) {
ff3187f6 7712 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7713 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7714 ssh2_pkt_addstring(pktout, "window-change");
7715 ssh2_pkt_addbool(pktout, 0);
7716 ssh2_pkt_adduint32(pktout, ssh->term_width);
7717 ssh2_pkt_adduint32(pktout, ssh->term_height);
7718 ssh2_pkt_adduint32(pktout, 0);
7719 ssh2_pkt_adduint32(pktout, 0);
7720 ssh2_pkt_send(ssh, pktout);
32874aea 7721 }
7722 }
7723 break;
374330e2 7724 }
7725}
7726
7727/*
125105d1 7728 * Return a list of the special codes that make sense in this
7729 * protocol.
7730 */
7731static const struct telnet_special *ssh_get_specials(void *handle)
7732{
786ba75e 7733 static const struct telnet_special ssh1_ignore_special[] = {
7734 {"IGNORE message", TS_NOP}
7735 };
7736 static const struct telnet_special ssh2_transport_specials[] = {
62638676 7737 {"IGNORE message", TS_NOP},
9442dd57 7738 {"Repeat key exchange", TS_REKEY},
62638676 7739 };
7740 static const struct telnet_special ssh2_session_specials[] = {
6f2d0cde 7741 {NULL, TS_SEP},
7742 {"Break", TS_BRK},
786ba75e 7743 /* These are the signal names defined by draft-ietf-secsh-connect-23.
6f2d0cde 7744 * They include all the ISO C signals, but are a subset of the POSIX
7745 * required signals. */
7746 {"SIGINT (Interrupt)", TS_SIGINT},
7747 {"SIGTERM (Terminate)", TS_SIGTERM},
7748 {"SIGKILL (Kill)", TS_SIGKILL},
7749 {"SIGQUIT (Quit)", TS_SIGQUIT},
7750 {"SIGHUP (Hangup)", TS_SIGHUP},
7751 {"More signals", TS_SUBMENU},
7752 {"SIGABRT", TS_SIGABRT}, {"SIGALRM", TS_SIGALRM},
7753 {"SIGFPE", TS_SIGFPE}, {"SIGILL", TS_SIGILL},
7754 {"SIGPIPE", TS_SIGPIPE}, {"SIGSEGV", TS_SIGSEGV},
7755 {"SIGUSR1", TS_SIGUSR1}, {"SIGUSR2", TS_SIGUSR2},
7756 {NULL, TS_EXITMENU}
62638676 7757 };
7758 static const struct telnet_special specials_end[] = {
6f2d0cde 7759 {NULL, TS_EXITMENU}
62638676 7760 };
786ba75e 7761 /* XXX review this length for any changes: */
7762 static struct telnet_special ssh_specials[lenof(ssh2_transport_specials) +
62638676 7763 lenof(ssh2_session_specials) +
7764 lenof(specials_end)];
125105d1 7765 Ssh ssh = (Ssh) handle;
62638676 7766 int i = 0;
7767#define ADD_SPECIALS(name) \
7768 do { \
7769 assert((i + lenof(name)) <= lenof(ssh_specials)); \
7770 memcpy(&ssh_specials[i], name, sizeof name); \
7771 i += lenof(name); \
7772 } while(0)
125105d1 7773
7774 if (ssh->version == 1) {
62638676 7775 /* Don't bother offering IGNORE if we've decided the remote
7776 * won't cope with it, since we wouldn't bother sending it if
7777 * asked anyway. */
7778 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE))
786ba75e 7779 ADD_SPECIALS(ssh1_ignore_special);
125105d1 7780 } else if (ssh->version == 2) {
786ba75e 7781 ADD_SPECIALS(ssh2_transport_specials);
62638676 7782 if (ssh->mainchan)
7783 ADD_SPECIALS(ssh2_session_specials);
7784 } /* else we're not ready yet */
7785
7786 if (i) {
7787 ADD_SPECIALS(specials_end);
7788 return ssh_specials;
7789 } else {
125105d1 7790 return NULL;
62638676 7791 }
7792#undef ADD_SPECIALS
125105d1 7793}
7794
7795/*
6abbf9e3 7796 * Send Telnet special codes. TS_EOF is useful for `plink', so you
7797 * can send an EOF and collect resulting output (e.g. `plink
7798 * hostname sort').
374330e2 7799 */
51470298 7800static void ssh_special(void *handle, Telnet_Special code)
32874aea 7801{
51470298 7802 Ssh ssh = (Ssh) handle;
ff3187f6 7803 struct Packet *pktout;
51470298 7804
6abbf9e3 7805 if (code == TS_EOF) {
51470298 7806 if (ssh->state != SSH_STATE_SESSION) {
32874aea 7807 /*
7808 * Buffer the EOF in case we are pre-SESSION, so we can
7809 * send it as soon as we reach SESSION.
7810 */
7811 if (code == TS_EOF)
51470298 7812 ssh->eof_needed = TRUE;
32874aea 7813 return;
7814 }
51470298 7815 if (ssh->version == 1) {
7816 send_packet(ssh, SSH1_CMSG_EOF, PKT_END);
0ed48730 7817 } else if (ssh->mainchan) {
ff3187f6 7818 struct Packet *pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF);
7819 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7820 ssh2_pkt_send(ssh, pktout);
32874aea 7821 }
7822 logevent("Sent EOF message");
125105d1 7823 } else if (code == TS_PING || code == TS_NOP) {
51470298 7824 if (ssh->state == SSH_STATE_CLOSED
7825 || ssh->state == SSH_STATE_PREPACKET) return;
7826 if (ssh->version == 1) {
7827 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE))
7828 send_packet(ssh, SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
32874aea 7829 } else {
ff3187f6 7830 pktout = ssh2_pkt_init(SSH2_MSG_IGNORE);
7831 ssh2_pkt_addstring_start(pktout);
590f6a5f 7832 ssh2_pkt_send_noqueue(ssh, pktout);
32874aea 7833 }
9442dd57 7834 } else if (code == TS_REKEY) {
7835 if (!ssh->kex_in_progress && ssh->version == 2) {
f382c87d 7836 do_ssh2_transport(ssh, "at user request", -1, NULL);
9442dd57 7837 }
125105d1 7838 } else if (code == TS_BRK) {
7839 if (ssh->state == SSH_STATE_CLOSED
7840 || ssh->state == SSH_STATE_PREPACKET) return;
7841 if (ssh->version == 1) {
7842 logevent("Unable to send BREAK signal in SSH1");
0ed48730 7843 } else if (ssh->mainchan) {
ff3187f6 7844 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7845 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7846 ssh2_pkt_addstring(pktout, "break");
7847 ssh2_pkt_addbool(pktout, 0);
7848 ssh2_pkt_adduint32(pktout, 0); /* default break length */
7849 ssh2_pkt_send(ssh, pktout);
125105d1 7850 }
6abbf9e3 7851 } else {
6f2d0cde 7852 /* Is is a POSIX signal? */
7853 char *signame = NULL;
7854 if (code == TS_SIGABRT) signame = "ABRT";
7855 if (code == TS_SIGALRM) signame = "ALRM";
7856 if (code == TS_SIGFPE) signame = "FPE";
7857 if (code == TS_SIGHUP) signame = "HUP";
7858 if (code == TS_SIGILL) signame = "ILL";
7859 if (code == TS_SIGINT) signame = "INT";
7860 if (code == TS_SIGKILL) signame = "KILL";
7861 if (code == TS_SIGPIPE) signame = "PIPE";
7862 if (code == TS_SIGQUIT) signame = "QUIT";
7863 if (code == TS_SIGSEGV) signame = "SEGV";
7864 if (code == TS_SIGTERM) signame = "TERM";
7865 if (code == TS_SIGUSR1) signame = "USR1";
7866 if (code == TS_SIGUSR2) signame = "USR2";
7867 /* The SSH-2 protocol does in principle support arbitrary named
7868 * signals, including signame@domain, but we don't support those. */
7869 if (signame) {
7870 /* It's a signal. */
7871 if (ssh->version == 2 && ssh->mainchan) {
ff3187f6 7872 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
7873 ssh2_pkt_adduint32(pktout, ssh->mainchan->remoteid);
7874 ssh2_pkt_addstring(pktout, "signal");
7875 ssh2_pkt_addbool(pktout, 0);
7876 ssh2_pkt_addstring(pktout, signame);
7877 ssh2_pkt_send(ssh, pktout);
6f2d0cde 7878 logeventf(ssh, "Sent signal SIG%s", signame);
7879 }
7880 } else {
7881 /* Never heard of it. Do nothing */
7882 }
6abbf9e3 7883 }
374330e2 7884}
7885
51470298 7886void *new_sock_channel(void *handle, Socket s)
d74d141c 7887{
51470298 7888 Ssh ssh = (Ssh) handle;
d74d141c 7889 struct ssh_channel *c;
3d88e64d 7890 c = snew(struct ssh_channel);
51470298 7891 c->ssh = ssh;
d74d141c 7892
7893 if (c) {
bc240b21 7894 c->remoteid = -1; /* to be set when open confirmed */
51470298 7895 c->localid = alloc_channel_id(ssh);
d74d141c 7896 c->closes = 0;
bc240b21 7897 c->type = CHAN_SOCKDATA_DORMANT;/* identify channel type */
d74d141c 7898 c->u.pfd.s = s;
013dd8c0 7899 bufchain_init(&c->v.v2.outbuffer);
51470298 7900 add234(ssh->channels, c);
d74d141c 7901 }
7902 return c;
7903}
7904
5471d09a 7905/*
7906 * This is called when stdout/stderr (the entity to which
7907 * from_backend sends data) manages to clear some backlog.
7908 */
ae9ae89f 7909static void ssh_unthrottle(void *handle, int bufsize)
5471d09a 7910{
51470298 7911 Ssh ssh = (Ssh) handle;
7912 if (ssh->version == 1) {
7913 if (ssh->v1_stdout_throttling && bufsize < SSH1_BUFFER_LIMIT) {
7914 ssh->v1_stdout_throttling = 0;
7915 ssh1_throttle(ssh, -1);
5471d09a 7916 }
7917 } else {
51470298 7918 if (ssh->mainchan && ssh->mainchan->closes == 0)
7919 ssh2_set_window(ssh->mainchan, OUR_V2_WINSIZE - bufsize);
5471d09a 7920 }
7921}
7922
6b78788a 7923void ssh_send_port_open(void *channel, char *hostname, int port, char *org)
d74d141c 7924{
7925 struct ssh_channel *c = (struct ssh_channel *)channel;
6b78788a 7926 Ssh ssh = c->ssh;
ff3187f6 7927 struct Packet *pktout;
d74d141c 7928
57356d63 7929 logeventf(ssh, "Opening forwarded connection to %s:%d", hostname, port);
d74d141c 7930
51470298 7931 if (ssh->version == 1) {
7932 send_packet(ssh, SSH1_MSG_PORT_OPEN,
bc240b21 7933 PKT_INT, c->localid,
7934 PKT_STR, hostname,
7935 PKT_INT, port,
31fb1866 7936 /* PKT_STR, <org:orgport>, */
bc240b21 7937 PKT_END);
7938 } else {
ff3187f6 7939 pktout = ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
7940 ssh2_pkt_addstring(pktout, "direct-tcpip");
7941 ssh2_pkt_adduint32(pktout, c->localid);
5471d09a 7942 c->v.v2.locwindow = OUR_V2_WINSIZE;
ff3187f6 7943 ssh2_pkt_adduint32(pktout, c->v.v2.locwindow);/* our window size */
7944 ssh2_pkt_adduint32(pktout, 0x4000UL); /* our max pkt size */
7945 ssh2_pkt_addstring(pktout, hostname);
7946 ssh2_pkt_adduint32(pktout, port);
bc240b21 7947 /*
7948 * We make up values for the originator data; partly it's
7949 * too much hassle to keep track, and partly I'm not
7950 * convinced the server should be told details like that
7951 * about my local network configuration.
7952 */
ff3187f6 7953 ssh2_pkt_addstring(pktout, "client-side-connection");
7954 ssh2_pkt_adduint32(pktout, 0);
7955 ssh2_pkt_send(ssh, pktout);
bc240b21 7956 }
d74d141c 7957}
7958
51470298 7959static Socket ssh_socket(void *handle)
32874aea 7960{
51470298 7961 Ssh ssh = (Ssh) handle;
7962 return ssh->s;
32874aea 7963}
8ccc75b0 7964
51470298 7965static int ssh_sendok(void *handle)
32874aea 7966{
51470298 7967 Ssh ssh = (Ssh) handle;
7968 return ssh->send_ok;
32874aea 7969}
fb09bf1c 7970
51470298 7971static int ssh_ldisc(void *handle, int option)
32874aea 7972{
51470298 7973 Ssh ssh = (Ssh) handle;
32874aea 7974 if (option == LD_ECHO)
51470298 7975 return ssh->echoing;
32874aea 7976 if (option == LD_EDIT)
51470298 7977 return ssh->editing;
0965bee0 7978 return FALSE;
7979}
7980
b9d7bcad 7981static void ssh_provide_ldisc(void *handle, void *ldisc)
7982{
7983 Ssh ssh = (Ssh) handle;
7984 ssh->ldisc = ldisc;
7985}
7986
a8327734 7987static void ssh_provide_logctx(void *handle, void *logctx)
7988{
7989 Ssh ssh = (Ssh) handle;
7990 ssh->logctx = logctx;
7991}
7992
51470298 7993static int ssh_return_exitcode(void *handle)
7994{
7995 Ssh ssh = (Ssh) handle;
3bb2f322 7996 if (ssh->s != NULL)
7997 return -1;
7998 else
7999 return (ssh->exitcode >= 0 ? ssh->exitcode : 0);
51470298 8000}
8001
8002/*
f89c3294 8003 * cfg_info for SSH is the currently running version of the
8004 * protocol. (1 for 1; 2 for 2; 0 for not-decided-yet.)
8005 */
8006static int ssh_cfg_info(void *handle)
8007{
8008 Ssh ssh = (Ssh) handle;
8009 return ssh->version;
8010}
8011
8012/*
51470298 8013 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
8014 * that fails. This variable is the means by which scp.c can reach
8015 * into the SSH code and find out which one it got.
8016 */
8017extern int ssh_fallback_cmd(void *handle)
d8d6c7e5 8018{
51470298 8019 Ssh ssh = (Ssh) handle;
8020 return ssh->fallback_cmd;
d8d6c7e5 8021}
8022
374330e2 8023Backend ssh_backend = {
8024 ssh_init,
fabd1805 8025 ssh_free,
86916870 8026 ssh_reconfig,
374330e2 8027 ssh_send,
5471d09a 8028 ssh_sendbuffer,
374330e2 8029 ssh_size,
4017be6d 8030 ssh_special,
125105d1 8031 ssh_get_specials,
8ccc75b0 8032 ssh_socket,
d8d6c7e5 8033 ssh_return_exitcode,
97db3be4 8034 ssh_sendok,
0965bee0 8035 ssh_ldisc,
b9d7bcad 8036 ssh_provide_ldisc,
a8327734 8037 ssh_provide_logctx,
5471d09a 8038 ssh_unthrottle,
f89c3294 8039 ssh_cfg_info,
97db3be4 8040 22
bc240b21 8041};
Local modifications for Simon Tatham's `PuTTY' SSH client and terminal emulator