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faq-alternate-localhost language tweak
[u/mdw/putty] / ssh.c
CommitLineData
374330e2 1#include <stdio.h>
2#include <stdlib.h>
fb09bf1c 3#include <stdarg.h>
4#include <assert.h>
374330e2 5
6#include "putty.h"
dacbd0e8 7#include "tree234.h"
fb09bf1c 8#include "ssh.h"
374330e2 9
10#ifndef FALSE
11#define FALSE 0
12#endif
13#ifndef TRUE
14#define TRUE 1
15#endif
16
32874aea 17#define SSH1_MSG_DISCONNECT 1 /* 0x1 */
18#define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
19#define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
20#define SSH1_CMSG_USER 4 /* 0x4 */
21#define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
22#define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
23#define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
24#define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
25#define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
26#define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
27#define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
28#define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
29#define SSH1_SMSG_SUCCESS 14 /* 0xe */
30#define SSH1_SMSG_FAILURE 15 /* 0xf */
31#define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
32#define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
33#define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
34#define SSH1_CMSG_EOF 19 /* 0x13 */
35#define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
36#define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
37#define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
38#define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
39#define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
40#define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
41#define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
42#define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
43#define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
44#define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
45#define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
46#define SSH1_MSG_IGNORE 32 /* 0x20 */
47#define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
48#define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
49#define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
50#define SSH1_MSG_DEBUG 36 /* 0x24 */
51#define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
52#define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
53#define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
54#define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
55#define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
56#define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
57#define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
58
59#define SSH1_AUTH_TIS 5 /* 0x5 */
60#define SSH1_AUTH_CCARD 16 /* 0x10 */
61
62#define SSH1_PROTOFLAG_SCREEN_NUMBER 1 /* 0x1 */
b96dc54c 63/* Mask for protoflags we will echo back to server if seen */
32874aea 64#define SSH1_PROTOFLAGS_SUPPORTED 0 /* 0x1 */
65
66#define SSH2_MSG_DISCONNECT 1 /* 0x1 */
67#define SSH2_MSG_IGNORE 2 /* 0x2 */
68#define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
69#define SSH2_MSG_DEBUG 4 /* 0x4 */
70#define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
71#define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
72#define SSH2_MSG_KEXINIT 20 /* 0x14 */
73#define SSH2_MSG_NEWKEYS 21 /* 0x15 */
74#define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
75#define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
76#define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */
77#define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
78#define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
79#define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
80#define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
81#define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
82#define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
83#define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
84#define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
85#define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
761187b6 86#define SSH2_MSG_USERAUTH_INFO_REQUEST 60 /* 0x3c */
87#define SSH2_MSG_USERAUTH_INFO_RESPONSE 61 /* 0x3d */
32874aea 88#define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
89#define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
90#define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
91#define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
92#define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
93#define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
94#define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
95#define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
96#define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
97#define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
98#define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
99#define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
100#define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
101#define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
102
00db133f 103/*
104 * Packet type contexts, so that ssh2_pkt_type can correctly decode
105 * the ambiguous type numbers back into the correct type strings.
106 */
107#define SSH2_PKTCTX_DHGROUP1 0x0001
108#define SSH2_PKTCTX_DHGEX 0x0002
109#define SSH2_PKTCTX_PUBLICKEY 0x0010
110#define SSH2_PKTCTX_PASSWORD 0x0020
111#define SSH2_PKTCTX_KBDINTER 0x0040
112#define SSH2_PKTCTX_AUTH_MASK 0x00F0
113
32874aea 114#define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
115#define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
116#define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
117#define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
118#define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
119#define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
120#define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
121#define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
122#define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
123#define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
124#define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
125#define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */
126#define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */
127#define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */
128#define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */
38c4a8da 129
130static const char *const ssh2_disconnect_reasons[] = {
131 NULL,
132 "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
133 "SSH_DISCONNECT_PROTOCOL_ERROR",
134 "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
135 "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
136 "SSH_DISCONNECT_MAC_ERROR",
137 "SSH_DISCONNECT_COMPRESSION_ERROR",
138 "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
139 "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
140 "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
141 "SSH_DISCONNECT_CONNECTION_LOST",
142 "SSH_DISCONNECT_BY_APPLICATION",
143 "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
144 "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
145 "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
146 "SSH_DISCONNECT_ILLEGAL_USER_NAME",
147};
9005f3ba 148
32874aea 149#define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
150#define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
151#define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
152#define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
d211621f 153
32874aea 154#define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
fb09bf1c 155
7d503c31 156/*
157 * Various remote-bug flags.
158 */
159#define BUG_CHOKES_ON_SSH1_IGNORE 1
160#define BUG_SSH2_HMAC 2
bd358db1 161#define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
0df73905 162#define BUG_CHOKES_ON_RSA 8
1dd353b5 163#define BUG_SSH2_RSA_PADDING 16
088bde77 164#define BUG_SSH2_DERIVEKEY 32
8e975795 165#define BUG_SSH2_DH_GEX 64
dda87a28 166#define BUG_SSH2_PK_SESSIONID 128
bd358db1 167
00db133f 168#define translate(x) if (type == x) return #x
51470298 169#define translatec(x,ctx) if (type == x && (pkt_ctx & ctx)) return #x
ae9ae89f 170static char *ssh1_pkt_type(int type)
00db133f 171{
172 translate(SSH1_MSG_DISCONNECT);
173 translate(SSH1_SMSG_PUBLIC_KEY);
174 translate(SSH1_CMSG_SESSION_KEY);
175 translate(SSH1_CMSG_USER);
176 translate(SSH1_CMSG_AUTH_RSA);
177 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE);
178 translate(SSH1_CMSG_AUTH_RSA_RESPONSE);
179 translate(SSH1_CMSG_AUTH_PASSWORD);
180 translate(SSH1_CMSG_REQUEST_PTY);
181 translate(SSH1_CMSG_WINDOW_SIZE);
182 translate(SSH1_CMSG_EXEC_SHELL);
183 translate(SSH1_CMSG_EXEC_CMD);
184 translate(SSH1_SMSG_SUCCESS);
185 translate(SSH1_SMSG_FAILURE);
186 translate(SSH1_CMSG_STDIN_DATA);
187 translate(SSH1_SMSG_STDOUT_DATA);
188 translate(SSH1_SMSG_STDERR_DATA);
189 translate(SSH1_CMSG_EOF);
190 translate(SSH1_SMSG_EXIT_STATUS);
191 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION);
192 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE);
193 translate(SSH1_MSG_CHANNEL_DATA);
194 translate(SSH1_MSG_CHANNEL_CLOSE);
195 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION);
196 translate(SSH1_SMSG_X11_OPEN);
197 translate(SSH1_CMSG_PORT_FORWARD_REQUEST);
198 translate(SSH1_MSG_PORT_OPEN);
199 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING);
200 translate(SSH1_SMSG_AGENT_OPEN);
201 translate(SSH1_MSG_IGNORE);
202 translate(SSH1_CMSG_EXIT_CONFIRMATION);
203 translate(SSH1_CMSG_X11_REQUEST_FORWARDING);
204 translate(SSH1_CMSG_AUTH_RHOSTS_RSA);
205 translate(SSH1_MSG_DEBUG);
206 translate(SSH1_CMSG_REQUEST_COMPRESSION);
207 translate(SSH1_CMSG_AUTH_TIS);
208 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE);
209 translate(SSH1_CMSG_AUTH_TIS_RESPONSE);
210 translate(SSH1_CMSG_AUTH_CCARD);
211 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE);
212 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE);
213 return "unknown";
214}
ae9ae89f 215static char *ssh2_pkt_type(int pkt_ctx, int type)
00db133f 216{
217 translate(SSH2_MSG_DISCONNECT);
218 translate(SSH2_MSG_IGNORE);
219 translate(SSH2_MSG_UNIMPLEMENTED);
220 translate(SSH2_MSG_DEBUG);
221 translate(SSH2_MSG_SERVICE_REQUEST);
222 translate(SSH2_MSG_SERVICE_ACCEPT);
223 translate(SSH2_MSG_KEXINIT);
224 translate(SSH2_MSG_NEWKEYS);
225 translatec(SSH2_MSG_KEXDH_INIT, SSH2_PKTCTX_DHGROUP1);
226 translatec(SSH2_MSG_KEXDH_REPLY, SSH2_PKTCTX_DHGROUP1);
227 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST, SSH2_PKTCTX_DHGEX);
228 translatec(SSH2_MSG_KEX_DH_GEX_GROUP, SSH2_PKTCTX_DHGEX);
229 translatec(SSH2_MSG_KEX_DH_GEX_INIT, SSH2_PKTCTX_DHGEX);
230 translatec(SSH2_MSG_KEX_DH_GEX_REPLY, SSH2_PKTCTX_DHGEX);
231 translate(SSH2_MSG_USERAUTH_REQUEST);
232 translate(SSH2_MSG_USERAUTH_FAILURE);
233 translate(SSH2_MSG_USERAUTH_SUCCESS);
234 translate(SSH2_MSG_USERAUTH_BANNER);
235 translatec(SSH2_MSG_USERAUTH_PK_OK, SSH2_PKTCTX_PUBLICKEY);
236 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, SSH2_PKTCTX_PASSWORD);
237 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST, SSH2_PKTCTX_KBDINTER);
238 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE, SSH2_PKTCTX_KBDINTER);
239 translate(SSH2_MSG_GLOBAL_REQUEST);
240 translate(SSH2_MSG_REQUEST_SUCCESS);
241 translate(SSH2_MSG_REQUEST_FAILURE);
242 translate(SSH2_MSG_CHANNEL_OPEN);
243 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
244 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE);
245 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
246 translate(SSH2_MSG_CHANNEL_DATA);
247 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA);
248 translate(SSH2_MSG_CHANNEL_EOF);
249 translate(SSH2_MSG_CHANNEL_CLOSE);
250 translate(SSH2_MSG_CHANNEL_REQUEST);
251 translate(SSH2_MSG_CHANNEL_SUCCESS);
252 translate(SSH2_MSG_CHANNEL_FAILURE);
253 return "unknown";
254}
255#undef translate
256#undef translatec
7d503c31 257
fb09bf1c 258#define GET_32BIT(cp) \
259 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
260 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
261 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
262 ((unsigned long)(unsigned char)(cp)[3]))
263
264#define PUT_32BIT(cp, value) { \
265 (cp)[0] = (unsigned char)((value) >> 24); \
266 (cp)[1] = (unsigned char)((value) >> 16); \
267 (cp)[2] = (unsigned char)((value) >> 8); \
268 (cp)[3] = (unsigned char)(value); }
269
7cca0d81 270enum { PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR, PKT_BIGNUM };
972a41c8 271
acddebd9 272/*
273 * Coroutine mechanics for the sillier bits of the code. If these
274 * macros look impenetrable to you, you might find it helpful to
275 * read
276 *
277 * http://www.chiark.greenend.org.uk/~sgtatham/coroutines.html
278 *
279 * which explains the theory behind these macros.
b624d1e6 280 *
281 * In particular, if you are getting `case expression not constant'
282 * errors when building with MS Visual Studio, this is because MS's
283 * Edit and Continue debugging feature causes their compiler to
284 * violate ANSI C. To disable Edit and Continue debugging:
285 *
286 * - right-click ssh.c in the FileView
287 * - click Settings
288 * - select the C/C++ tab and the General category
289 * - under `Debug info:', select anything _other_ than `Program
290 * Database for Edit and Continue'.
acddebd9 291 */
51470298 292#define crBegin(v) { int *crLine = &v; switch(v) { case 0:;
293#define crState(t) \
294 struct t *s; \
3d88e64d 295 if (!ssh->t) ssh->t = snew(struct t); \
51470298 296 s = ssh->t;
297#define crFinish(z) } *crLine = 0; return (z); }
298#define crFinishV } *crLine = 0; return; }
374330e2 299#define crReturn(z) \
300 do {\
51470298 301 *crLine =__LINE__; return (z); case __LINE__:;\
374330e2 302 } while (0)
303#define crReturnV \
304 do {\
51470298 305 *crLine=__LINE__; return; case __LINE__:;\
374330e2 306 } while (0)
51470298 307#define crStop(z) do{ *crLine = 0; return (z); }while(0)
308#define crStopV do{ *crLine = 0; return; }while(0)
fb09bf1c 309#define crWaitUntil(c) do { crReturn(0); } while (!(c))
7cca0d81 310#define crWaitUntilV(c) do { crReturnV; } while (!(c))
374330e2 311
51470298 312typedef struct ssh_tag *Ssh;
313
51470298 314static void ssh2_pkt_init(Ssh, int pkt_type);
315static void ssh2_pkt_addbool(Ssh, unsigned char value);
316static void ssh2_pkt_adduint32(Ssh, unsigned long value);
317static void ssh2_pkt_addstring_start(Ssh);
318static void ssh2_pkt_addstring_str(Ssh, char *data);
319static void ssh2_pkt_addstring_data(Ssh, char *data, int len);
320static void ssh2_pkt_addstring(Ssh, char *data);
d8baa528 321static unsigned char *ssh2_mpint_fmt(Bignum b, int *len);
51470298 322static void ssh2_pkt_addmp(Ssh, Bignum b);
323static int ssh2_pkt_construct(Ssh);
324static void ssh2_pkt_send(Ssh);
839f10db 325static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt);
326static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt);
3d63ca2e 327
5471d09a 328/*
329 * Buffer management constants. There are several of these for
330 * various different purposes:
331 *
332 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
333 * on a local data stream before we throttle the whole SSH
334 * connection (in SSH1 only). Throttling the whole connection is
335 * pretty drastic so we set this high in the hope it won't
336 * happen very often.
337 *
338 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
339 * on the SSH connection itself before we defensively throttle
340 * _all_ local data streams. This is pretty drastic too (though
341 * thankfully unlikely in SSH2 since the window mechanism should
342 * ensure that the server never has any need to throttle its end
343 * of the connection), so we set this high as well.
344 *
345 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
346 * channels.
347 */
348
349#define SSH1_BUFFER_LIMIT 32768
350#define SSH_MAX_BACKLOG 32768
351#define OUR_V2_WINSIZE 16384
d74d141c 352
a92dd380 353const static struct ssh_kex *kex_algs[] = {
a92dd380 354 &ssh_diffiehellman_gex,
32874aea 355 &ssh_diffiehellman
356};
e5574168 357
85cc02bb 358const static struct ssh_signkey *hostkey_algs[] = { &ssh_rsa, &ssh_dss };
e5574168 359
e0e1a00d 360static void *nullmac_make_context(void)
361{
362 return NULL;
363}
364static void nullmac_free_context(void *handle)
365{
366}
367static void nullmac_key(void *handle, unsigned char *key)
32874aea 368{
369}
e0e1a00d 370static void nullmac_generate(void *handle, unsigned char *blk, int len,
32874aea 371 unsigned long seq)
372{
373}
e0e1a00d 374static int nullmac_verify(void *handle, unsigned char *blk, int len,
375 unsigned long seq)
32874aea 376{
377 return 1;
378}
57476f6b 379const static struct ssh_mac ssh_mac_none = {
e0e1a00d 380 nullmac_make_context, nullmac_free_context, nullmac_key,
381 nullmac_generate, nullmac_verify, "none", 0
e5574168 382};
8b2715b2 383const static struct ssh_mac *macs[] = {
32874aea 384 &ssh_sha1, &ssh_md5, &ssh_mac_none
385};
8b2715b2 386const static struct ssh_mac *buggymacs[] = {
32874aea 387 &ssh_sha1_buggy, &ssh_md5, &ssh_mac_none
388};
e5574168 389
5366aed8 390static void *ssh_comp_none_init(void)
391{
392 return NULL;
393}
394static void ssh_comp_none_cleanup(void *handle)
32874aea 395{
396}
5366aed8 397static int ssh_comp_none_block(void *handle, unsigned char *block, int len,
32874aea 398 unsigned char **outblock, int *outlen)
399{
400 return 0;
401}
5366aed8 402static int ssh_comp_none_disable(void *handle)
32874aea 403{
4ba9b64b 404 return 0;
405}
57476f6b 406const static struct ssh_compress ssh_comp_none = {
4ba9b64b 407 "none",
5366aed8 408 ssh_comp_none_init, ssh_comp_none_cleanup, ssh_comp_none_block,
409 ssh_comp_none_init, ssh_comp_none_cleanup, ssh_comp_none_block,
410 ssh_comp_none_disable, NULL
e5574168 411};
4ba9b64b 412extern const struct ssh_compress ssh_zlib;
413const static struct ssh_compress *compressions[] = {
32874aea 414 &ssh_zlib, &ssh_comp_none
415};
374330e2 416
32874aea 417enum { /* channel types */
783415f8 418 CHAN_MAINSESSION,
419 CHAN_X11,
420 CHAN_AGENT,
bc240b21 421 CHAN_SOCKDATA,
422 CHAN_SOCKDATA_DORMANT /* one the remote hasn't confirmed */
783415f8 423};
424
dacbd0e8 425/*
426 * 2-3-4 tree storing channels.
427 */
428struct ssh_channel {
51470298 429 Ssh ssh; /* pointer back to main context */
d211621f 430 unsigned remoteid, localid;
dacbd0e8 431 int type;
0357890f 432 /*
433 * In SSH1, this value contains four bits:
434 *
435 * 1 We have sent SSH1_MSG_CHANNEL_CLOSE.
436 * 2 We have sent SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
437 * 4 We have received SSH1_MSG_CHANNEL_CLOSE.
438 * 8 We have received SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION.
439 *
440 * A channel is completely finished with when all four bits are set.
441 */
dacbd0e8 442 int closes;
5471d09a 443 union {
444 struct ssh1_data_channel {
445 int throttling;
446 } v1;
447 struct ssh2_data_channel {
448 bufchain outbuffer;
449 unsigned remwindow, remmaxpkt;
450 unsigned locwindow;
451 } v2;
452 } v;
dacbd0e8 453 union {
32874aea 454 struct ssh_agent_channel {
455 unsigned char *message;
456 unsigned char msglen[4];
457 int lensofar, totallen;
458 } a;
459 struct ssh_x11_channel {
460 Socket s;
461 } x11;
d74d141c 462 struct ssh_pfd_channel {
463 Socket s;
464 } pfd;
dacbd0e8 465 } u;
466};
57476f6b 467
d74d141c 468/*
bc240b21 469 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
470 * 2 use this structure in different ways, reflecting SSH 2's
471 * altogether saner approach to port forwarding.
472 *
473 * In SSH 1, you arrange a remote forwarding by sending the server
474 * the remote port number, and the local destination host:port.
475 * When a connection comes in, the server sends you back that
476 * host:port pair, and you connect to it. This is a ready-made
477 * security hole if you're not on the ball: a malicious server
478 * could send you back _any_ host:port pair, so if you trustingly
479 * connect to the address it gives you then you've just opened the
480 * entire inside of your corporate network just by connecting
481 * through it to a dodgy SSH server. Hence, we must store a list of
482 * host:port pairs we _are_ trying to forward to, and reject a
483 * connection request from the server if it's not in the list.
484 *
485 * In SSH 2, each side of the connection minds its own business and
486 * doesn't send unnecessary information to the other. You arrange a
487 * remote forwarding by sending the server just the remote port
488 * number. When a connection comes in, the server tells you which
489 * of its ports was connected to; and _you_ have to remember what
490 * local host:port pair went with that port number.
491 *
492 * Hence: in SSH 1 this structure stores host:port pairs we intend
493 * to allow connections to, and is indexed by those host:port
494 * pairs. In SSH 2 it stores a mapping from source port to
495 * destination host:port pair, and is indexed by source port.
d74d141c 496 */
497struct ssh_rportfwd {
bc240b21 498 unsigned sport, dport;
499 char dhost[256];
d74d141c 500};
501
57476f6b 502struct Packet {
503 long length;
504 int type;
505 unsigned char *data;
506 unsigned char *body;
507 long savedpos;
508 long maxlen;
509};
510
51470298 511static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt);
512static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt);
513static void ssh_size(void *handle, int width, int height);
514static void ssh_special(void *handle, Telnet_Special);
5471d09a 515static int ssh2_try_send(struct ssh_channel *c);
51470298 516static void ssh2_add_channel_data(struct ssh_channel *c, char *buf, int len);
517static void ssh_throttle_all(Ssh ssh, int enable, int bufsize);
5471d09a 518static void ssh2_set_window(struct ssh_channel *c, unsigned newwin);
51470298 519static int ssh_sendbuffer(void *handle);
36f94d1f 520static void ssh_do_close(Ssh ssh);
57476f6b 521
51470298 522struct rdpkt1_state_tag {
57476f6b 523 long len, pad, biglen, to_read;
524 unsigned long realcrc, gotcrc;
525 unsigned char *p;
526 int i;
527 int chunk;
51470298 528};
57476f6b 529
51470298 530struct rdpkt2_state_tag {
960e736a 531 long len, pad, payload, packetlen, maclen;
532 int i;
533 int cipherblk;
534 unsigned long incoming_sequence;
51470298 535};
536
537struct ssh_tag {
538 const struct plug_function_table *fn;
539 /* the above field _must_ be first in the structure */
540
541 SHA_State exhash, exhashbase;
542
543 Socket s;
544
b9d7bcad 545 void *ldisc;
a8327734 546 void *logctx;
b9d7bcad 547
51470298 548 unsigned char session_key[32];
549 int v1_compressing;
550 int v1_remote_protoflags;
551 int v1_local_protoflags;
552 int agentfwd_enabled;
553 int X11_fwd_enabled;
554 int remote_bugs;
555 const struct ssh_cipher *cipher;
371e569c 556 void *v1_cipher_ctx;
0183b242 557 void *crcda_ctx;
51470298 558 const struct ssh2_cipher *cscipher, *sccipher;
371e569c 559 void *cs_cipher_ctx, *sc_cipher_ctx;
51470298 560 const struct ssh_mac *csmac, *scmac;
e0e1a00d 561 void *cs_mac_ctx, *sc_mac_ctx;
51470298 562 const struct ssh_compress *cscomp, *sccomp;
5366aed8 563 void *cs_comp_ctx, *sc_comp_ctx;
51470298 564 const struct ssh_kex *kex;
565 const struct ssh_signkey *hostkey;
566 unsigned char v2_session_id[20];
27cd7fc2 567 void *kex_ctx;
51470298 568
569 char *savedhost;
570 int savedport;
571 int send_ok;
572 int echoing, editing;
573
574 void *frontend;
575
db219738 576 int ospeed, ispeed; /* temporaries */
51470298 577 int term_width, term_height;
578
579 tree234 *channels; /* indexed by local id */
580 struct ssh_channel *mainchan; /* primary session channel */
581 int exitcode;
582
583 tree234 *rportfwds;
584
585 enum {
586 SSH_STATE_PREPACKET,
587 SSH_STATE_BEFORE_SIZE,
588 SSH_STATE_INTERMED,
589 SSH_STATE_SESSION,
590 SSH_STATE_CLOSED
591 } state;
592
593 int size_needed, eof_needed;
594
595 struct Packet pktin;
596 struct Packet pktout;
597 unsigned char *deferred_send_data;
598 int deferred_len, deferred_size;
599
600 /*
601 * Gross hack: pscp will try to start SFTP but fall back to
602 * scp1 if that fails. This variable is the means by which
603 * scp.c can reach into the SSH code and find out which one it
604 * got.
605 */
606 int fallback_cmd;
607
608 /*
609 * Used for username and password input.
610 */
611 char *userpass_input_buffer;
612 int userpass_input_buflen;
613 int userpass_input_bufpos;
614 int userpass_input_echo;
615
616 char *portfwd_strptr;
617 int pkt_ctx;
618
302121de 619 void *x11auth;
620
51470298 621 int version;
622 int v1_throttle_count;
623 int overall_bufsize;
624 int throttled_all;
625 int v1_stdout_throttling;
626 int v2_outgoing_sequence;
627
628 int ssh1_rdpkt_crstate;
629 int ssh2_rdpkt_crstate;
630 int do_ssh_init_crstate;
631 int ssh_gotdata_crstate;
632 int ssh1_protocol_crstate;
633 int do_ssh1_login_crstate;
634 int do_ssh2_transport_crstate;
635 int do_ssh2_authconn_crstate;
636
637 void *do_ssh_init_state;
638 void *do_ssh1_login_state;
639 void *do_ssh2_transport_state;
640 void *do_ssh2_authconn_state;
641
642 struct rdpkt1_state_tag rdpkt1_state;
643 struct rdpkt2_state_tag rdpkt2_state;
644
645 void (*protocol) (Ssh ssh, unsigned char *in, int inlen, int ispkt);
646 int (*s_rdpkt) (Ssh ssh, unsigned char **data, int *datalen);
86916870 647
648 /*
649 * We maintain a full _copy_ of a Config structure here, not
650 * merely a pointer to it. That way, when we're passed a new
651 * one for reconfiguration, we can check the differences and
652 * potentially reconfigure port forwardings etc in mid-session.
653 */
654 Config cfg;
839f10db 655
656 /*
657 * Used to transfer data back from async agent callbacks.
658 */
659 void *agent_response;
660 int agent_response_len;
51470298 661};
960e736a 662
382908ad 663#define logevent(s) logevent(ssh->frontend, s)
a8327734 664
665/* logevent, only printf-formatted. */
cbe2d68f 666static void logeventf(Ssh ssh, const char *fmt, ...)
a8327734 667{
668 va_list ap;
57356d63 669 char *buf;
a8327734 670
671 va_start(ap, fmt);
57356d63 672 buf = dupvprintf(fmt, ap);
a8327734 673 va_end(ap);
57356d63 674 logevent(buf);
57356d63 675 sfree(buf);
a8327734 676}
677
6b5cf8b4 678#define bombout(msg) \
679 do { \
680 char *text = dupprintf msg; \
36f94d1f 681 ssh_do_close(ssh); \
6b5cf8b4 682 logevent(text); \
683 connection_fatal(ssh->frontend, "%s", text); \
684 sfree(text); \
685 } while (0)
a8327734 686
32874aea 687static int ssh_channelcmp(void *av, void *bv)
688{
689 struct ssh_channel *a = (struct ssh_channel *) av;
690 struct ssh_channel *b = (struct ssh_channel *) bv;
691 if (a->localid < b->localid)
692 return -1;
693 if (a->localid > b->localid)
694 return +1;
dacbd0e8 695 return 0;
696}
32874aea 697static int ssh_channelfind(void *av, void *bv)
698{
699 unsigned *a = (unsigned *) av;
700 struct ssh_channel *b = (struct ssh_channel *) bv;
701 if (*a < b->localid)
702 return -1;
703 if (*a > b->localid)
704 return +1;
dacbd0e8 705 return 0;
706}
707
bc240b21 708static int ssh_rportcmp_ssh1(void *av, void *bv)
d74d141c 709{
710 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
711 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
712 int i;
bc240b21 713 if ( (i = strcmp(a->dhost, b->dhost)) != 0)
d74d141c 714 return i < 0 ? -1 : +1;
bc240b21 715 if (a->dport > b->dport)
716 return +1;
717 if (a->dport < b->dport)
718 return -1;
719 return 0;
720}
721
722static int ssh_rportcmp_ssh2(void *av, void *bv)
723{
724 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
725 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
cdcbdf3b 726
bc240b21 727 if (a->sport > b->sport)
d74d141c 728 return +1;
bc240b21 729 if (a->sport < b->sport)
730 return -1;
d74d141c 731 return 0;
732}
733
51470298 734static int alloc_channel_id(Ssh ssh)
32874aea 735{
260f3dec 736 const unsigned CHANNEL_NUMBER_OFFSET = 256;
737 unsigned low, high, mid;
d2371c81 738 int tsize;
739 struct ssh_channel *c;
740
741 /*
742 * First-fit allocation of channel numbers: always pick the
743 * lowest unused one. To do this, binary-search using the
744 * counted B-tree to find the largest channel ID which is in a
745 * contiguous sequence from the beginning. (Precisely
746 * everything in that sequence must have ID equal to its tree
747 * index plus CHANNEL_NUMBER_OFFSET.)
748 */
51470298 749 tsize = count234(ssh->channels);
d2371c81 750
32874aea 751 low = -1;
752 high = tsize;
d2371c81 753 while (high - low > 1) {
754 mid = (high + low) / 2;
51470298 755 c = index234(ssh->channels, mid);
d2371c81 756 if (c->localid == mid + CHANNEL_NUMBER_OFFSET)
757 low = mid; /* this one is fine */
758 else
759 high = mid; /* this one is past it */
760 }
761 /*
762 * Now low points to either -1, or the tree index of the
763 * largest ID in the initial sequence.
764 */
765 {
766 unsigned i = low + 1 + CHANNEL_NUMBER_OFFSET;
51470298 767 assert(NULL == find234(ssh->channels, &i, ssh_channelfind));
d2371c81 768 }
769 return low + 1 + CHANNEL_NUMBER_OFFSET;
770}
771
9fab77dc 772static void c_write(Ssh ssh, const char *buf, int len)
32874aea 773{
67779be7 774 if ((flags & FLAG_STDERR)) {
32874aea 775 int i;
776 for (i = 0; i < len; i++)
777 if (buf[i] != '\r')
778 fputc(buf[i], stderr);
fb09bf1c 779 return;
780 }
51470298 781 from_backend(ssh->frontend, 1, buf, len);
3bdaf79d 782}
783
9fab77dc 784static void c_write_untrusted(Ssh ssh, const char *buf, int len)
32874aea 785{
a209e957 786 int i;
787 for (i = 0; i < len; i++) {
32874aea 788 if (buf[i] == '\n')
51470298 789 c_write(ssh, "\r\n", 2);
32874aea 790 else if ((buf[i] & 0x60) || (buf[i] == '\r'))
51470298 791 c_write(ssh, buf + i, 1);
a209e957 792 }
793}
794
9fab77dc 795static void c_write_str(Ssh ssh, const char *buf)
32874aea 796{
51470298 797 c_write(ssh, buf, strlen(buf));
1408a877 798}
799
fb09bf1c 800/*
801 * Collect incoming data in the incoming packet buffer.
e5574168 802 * Decipher and verify the packet when it is completely read.
803 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
fb09bf1c 804 * Update the *data and *datalen variables.
805 * Return the additional nr of bytes needed, or 0 when
806 * a complete packet is available.
807 */
51470298 808static int ssh1_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
fb09bf1c 809{
51470298 810 struct rdpkt1_state_tag *st = &ssh->rdpkt1_state;
374330e2 811
51470298 812 crBegin(ssh->ssh1_rdpkt_crstate);
374330e2 813
32874aea 814 next_packet:
37508af4 815
51470298 816 ssh->pktin.type = 0;
817 ssh->pktin.length = 0;
374330e2 818
57476f6b 819 for (st->i = st->len = 0; st->i < 4; st->i++) {
fb09bf1c 820 while ((*datalen) == 0)
32874aea 821 crReturn(4 - st->i);
57476f6b 822 st->len = (st->len << 8) + **data;
fb09bf1c 823 (*data)++, (*datalen)--;
824 }
374330e2 825
57476f6b 826 st->pad = 8 - (st->len % 8);
827 st->biglen = st->len + st->pad;
51470298 828 ssh->pktin.length = st->len - 5;
fb09bf1c 829
51470298 830 if (ssh->pktin.maxlen < st->biglen) {
831 ssh->pktin.maxlen = st->biglen;
3d88e64d 832 ssh->pktin.data = sresize(ssh->pktin.data, st->biglen + APIEXTRA,
833 unsigned char);
fb09bf1c 834 }
374330e2 835
57476f6b 836 st->to_read = st->biglen;
51470298 837 st->p = ssh->pktin.data;
57476f6b 838 while (st->to_read > 0) {
32874aea 839 st->chunk = st->to_read;
fb09bf1c 840 while ((*datalen) == 0)
57476f6b 841 crReturn(st->to_read);
842 if (st->chunk > (*datalen))
843 st->chunk = (*datalen);
844 memcpy(st->p, *data, st->chunk);
845 *data += st->chunk;
846 *datalen -= st->chunk;
847 st->p += st->chunk;
848 st->to_read -= st->chunk;
fb09bf1c 849 }
374330e2 850
0183b242 851 if (ssh->cipher && detect_attack(ssh->crcda_ctx, ssh->pktin.data,
852 st->biglen, NULL)) {
6b5cf8b4 853 bombout(("Network attack (CRC compensation) detected!"));
7ffdbc1a 854 crStop(0);
9a3a93a5 855 }
856
51470298 857 if (ssh->cipher)
371e569c 858 ssh->cipher->decrypt(ssh->v1_cipher_ctx, ssh->pktin.data, st->biglen);
374330e2 859
71bedafe 860 st->realcrc = crc32_compute(ssh->pktin.data, st->biglen - 4);
51470298 861 st->gotcrc = GET_32BIT(ssh->pktin.data + st->biglen - 4);
57476f6b 862 if (st->gotcrc != st->realcrc) {
6b5cf8b4 863 bombout(("Incorrect CRC received on packet"));
7ffdbc1a 864 crStop(0);
fb09bf1c 865 }
572f871e 866
51470298 867 ssh->pktin.body = ssh->pktin.data + st->pad + 1;
0016d70b 868 ssh->pktin.savedpos = 0;
4ba9b64b 869
51470298 870 if (ssh->v1_compressing) {
4ba9b64b 871 unsigned char *decompblk;
872 int decomplen;
36b8d9bb 873 if (!zlib_decompress_block(ssh->sc_comp_ctx,
874 ssh->pktin.body - 1, ssh->pktin.length + 1,
875 &decompblk, &decomplen)) {
876 bombout(("Zlib decompression encountered invalid data"));
877 crStop(0);
878 }
4ba9b64b 879
51470298 880 if (ssh->pktin.maxlen < st->pad + decomplen) {
881 ssh->pktin.maxlen = st->pad + decomplen;
3d88e64d 882 ssh->pktin.data = sresize(ssh->pktin.data,
883 ssh->pktin.maxlen + APIEXTRA,
884 unsigned char);
51470298 885 ssh->pktin.body = ssh->pktin.data + st->pad + 1;
4ba9b64b 886 }
887
51470298 888 memcpy(ssh->pktin.body - 1, decompblk, decomplen);
dcbde236 889 sfree(decompblk);
51470298 890 ssh->pktin.length = decomplen - 1;
4ba9b64b 891 }
892
51470298 893 ssh->pktin.type = ssh->pktin.body[-1];
00db133f 894
a8327734 895 if (ssh->logctx)
896 log_packet(ssh->logctx,
897 PKT_INCOMING, ssh->pktin.type,
898 ssh1_pkt_type(ssh->pktin.type),
899 ssh->pktin.body, ssh->pktin.length);
00db133f 900
51470298 901 if (ssh->pktin.type == SSH1_SMSG_STDOUT_DATA ||
902 ssh->pktin.type == SSH1_SMSG_STDERR_DATA ||
903 ssh->pktin.type == SSH1_MSG_DEBUG ||
904 ssh->pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE ||
905 ssh->pktin.type == SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
906 long stringlen = GET_32BIT(ssh->pktin.body);
907 if (stringlen + 4 != ssh->pktin.length) {
6b5cf8b4 908 bombout(("Received data packet with bogus string length"));
7ffdbc1a 909 crStop(0);
32874aea 910 }
fb09bf1c 911 }
912
51470298 913 if (ssh->pktin.type == SSH1_MSG_DEBUG) {
fb09bf1c 914 /* log debug message */
eb4504cc 915 char buf[512];
51470298 916 int stringlen = GET_32BIT(ssh->pktin.body);
eb4504cc 917 strcpy(buf, "Remote debug message: ");
918 if (stringlen > 480)
919 stringlen = 480;
51470298 920 memcpy(buf + 8, ssh->pktin.body + 4, stringlen);
3d63ca2e 921 buf[8 + stringlen] = '\0';
fb09bf1c 922 logevent(buf);
923 goto next_packet;
51470298 924 } else if (ssh->pktin.type == SSH1_MSG_IGNORE) {
fb09bf1c 925 /* do nothing */
926 goto next_packet;
927 }
928
51470298 929 if (ssh->pktin.type == SSH1_MSG_DISCONNECT) {
38c4a8da 930 /* log reason code in disconnect message */
931 char buf[256];
51470298 932 unsigned msglen = GET_32BIT(ssh->pktin.body);
260f3dec 933 unsigned nowlen;
38c4a8da 934 strcpy(buf, "Remote sent disconnect: ");
935 nowlen = strlen(buf);
32874aea 936 if (msglen > sizeof(buf) - nowlen - 1)
937 msglen = sizeof(buf) - nowlen - 1;
51470298 938 memcpy(buf + nowlen, ssh->pktin.body + 4, msglen);
32874aea 939 buf[nowlen + msglen] = '\0';
247308b5 940 /* logevent(buf); (this is now done within the bombout macro) */
6b5cf8b4 941 bombout(("Server sent disconnect message:\n\"%s\"", buf+nowlen));
7ffdbc1a 942 crStop(0);
38c4a8da 943 }
944
fb09bf1c 945 crFinish(0);
946}
947
51470298 948static int ssh2_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
e5574168 949{
51470298 950 struct rdpkt2_state_tag *st = &ssh->rdpkt2_state;
e5574168 951
51470298 952 crBegin(ssh->ssh2_rdpkt_crstate);
e5574168 953
32874aea 954 next_packet:
51470298 955 ssh->pktin.type = 0;
956 ssh->pktin.length = 0;
957 if (ssh->sccipher)
958 st->cipherblk = ssh->sccipher->blksize;
e5574168 959 else
32874aea 960 st->cipherblk = 8;
960e736a 961 if (st->cipherblk < 8)
32874aea 962 st->cipherblk = 8;
960e736a 963
51470298 964 if (ssh->pktin.maxlen < st->cipherblk) {
965 ssh->pktin.maxlen = st->cipherblk;
3d88e64d 966 ssh->pktin.data = sresize(ssh->pktin.data, st->cipherblk + APIEXTRA,
967 unsigned char);
e5574168 968 }
969
970 /*
971 * Acquire and decrypt the first block of the packet. This will
972 * contain the length and padding details.
973 */
32874aea 974 for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) {
e5574168 975 while ((*datalen) == 0)
32874aea 976 crReturn(st->cipherblk - st->i);
51470298 977 ssh->pktin.data[st->i] = *(*data)++;
32874aea 978 (*datalen)--;
e5574168 979 }
4252c9cc 980
51470298 981 if (ssh->sccipher)
371e569c 982 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
983 ssh->pktin.data, st->cipherblk);
e5574168 984
985 /*
986 * Now get the length and padding figures.
987 */
51470298 988 st->len = GET_32BIT(ssh->pktin.data);
989 st->pad = ssh->pktin.data[4];
e5574168 990
991 /*
717dc483 992 * _Completely_ silly lengths should be stomped on before they
993 * do us any more damage.
994 */
995 if (st->len < 0 || st->pad < 0 || st->len + st->pad < 0) {
6b5cf8b4 996 bombout(("Incoming packet was garbled on decryption"));
7ffdbc1a 997 crStop(0);
717dc483 998 }
999
1000 /*
e5574168 1001 * This enables us to deduce the payload length.
1002 */
960e736a 1003 st->payload = st->len - st->pad - 1;
e5574168 1004
51470298 1005 ssh->pktin.length = st->payload + 5;
e5574168 1006
1007 /*
1008 * So now we can work out the total packet length.
1009 */
960e736a 1010 st->packetlen = st->len + 4;
51470298 1011 st->maclen = ssh->scmac ? ssh->scmac->len : 0;
e5574168 1012
1013 /*
1014 * Adjust memory allocation if packet is too big.
1015 */
51470298 1016 if (ssh->pktin.maxlen < st->packetlen + st->maclen) {
1017 ssh->pktin.maxlen = st->packetlen + st->maclen;
3d88e64d 1018 ssh->pktin.data = sresize(ssh->pktin.data,
1019 ssh->pktin.maxlen + APIEXTRA,
1020 unsigned char);
e5574168 1021 }
1022
1023 /*
1024 * Read and decrypt the remainder of the packet.
1025 */
32874aea 1026 for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen;
1027 st->i++) {
e5574168 1028 while ((*datalen) == 0)
960e736a 1029 crReturn(st->packetlen + st->maclen - st->i);
51470298 1030 ssh->pktin.data[st->i] = *(*data)++;
32874aea 1031 (*datalen)--;
e5574168 1032 }
1033 /* Decrypt everything _except_ the MAC. */
51470298 1034 if (ssh->sccipher)
371e569c 1035 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
1036 ssh->pktin.data + st->cipherblk,
51470298 1037 st->packetlen - st->cipherblk);
e5574168 1038
1039 /*
1040 * Check the MAC.
1041 */
51470298 1042 if (ssh->scmac
e0e1a00d 1043 && !ssh->scmac->verify(ssh->sc_mac_ctx, ssh->pktin.data, st->len + 4,
51470298 1044 st->incoming_sequence)) {
6b5cf8b4 1045 bombout(("Incorrect MAC received on packet"));
7ffdbc1a 1046 crStop(0);
8d5de777 1047 }
32874aea 1048 st->incoming_sequence++; /* whether or not we MACed */
e5574168 1049
4ba9b64b 1050 /*
1051 * Decompress packet payload.
1052 */
1053 {
1054 unsigned char *newpayload;
1055 int newlen;
51470298 1056 if (ssh->sccomp &&
5366aed8 1057 ssh->sccomp->decompress(ssh->sc_comp_ctx,
1058 ssh->pktin.data + 5, ssh->pktin.length - 5,
51470298 1059 &newpayload, &newlen)) {
1060 if (ssh->pktin.maxlen < newlen + 5) {
1061 ssh->pktin.maxlen = newlen + 5;
3d88e64d 1062 ssh->pktin.data = sresize(ssh->pktin.data,
1063 ssh->pktin.maxlen + APIEXTRA,
1064 unsigned char);
4ba9b64b 1065 }
51470298 1066 ssh->pktin.length = 5 + newlen;
1067 memcpy(ssh->pktin.data + 5, newpayload, newlen);
dcbde236 1068 sfree(newpayload);
4ba9b64b 1069 }
1070 }
1071
51470298 1072 ssh->pktin.savedpos = 6;
0016d70b 1073 ssh->pktin.body = ssh->pktin.data;
51470298 1074 ssh->pktin.type = ssh->pktin.data[5];
e5574168 1075
a8327734 1076 if (ssh->logctx)
1077 log_packet(ssh->logctx, PKT_INCOMING, ssh->pktin.type,
1078 ssh2_pkt_type(ssh->pkt_ctx, ssh->pktin.type),
1079 ssh->pktin.data+6, ssh->pktin.length-6);
00db133f 1080
51470298 1081 switch (ssh->pktin.type) {
3d63ca2e 1082 /*
1083 * These packets we must handle instantly.
1084 */
1085 case SSH2_MSG_DISCONNECT:
1086 {
1087 /* log reason code in disconnect message */
57356d63 1088 char *buf;
1089 int nowlen;
51470298 1090 int reason = GET_32BIT(ssh->pktin.data + 6);
1091 unsigned msglen = GET_32BIT(ssh->pktin.data + 10);
57356d63 1092
3d63ca2e 1093 if (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) {
57356d63 1094 buf = dupprintf("Received disconnect message (%s)",
1095 ssh2_disconnect_reasons[reason]);
3d63ca2e 1096 } else {
57356d63 1097 buf = dupprintf("Received disconnect message (unknown"
1098 " type %d)", reason);
3d63ca2e 1099 }
1100 logevent(buf);
57356d63 1101 sfree(buf);
1102 buf = dupprintf("Disconnection message text: %n%.*s",
33b82b22 1103 &nowlen, msglen, ssh->pktin.data + 14);
3d63ca2e 1104 logevent(buf);
6b5cf8b4 1105 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
3d63ca2e 1106 reason,
1107 (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) ?
1108 ssh2_disconnect_reasons[reason] : "unknown",
1109 buf+nowlen));
57356d63 1110 sfree(buf);
7ffdbc1a 1111 crStop(0);
3d63ca2e 1112 }
1113 break;
1114 case SSH2_MSG_IGNORE:
1115 goto next_packet;
1116 case SSH2_MSG_DEBUG:
1117 {
1118 /* log the debug message */
1119 char buf[512];
51470298 1120 /* int display = ssh->pktin.body[6]; */
1121 int stringlen = GET_32BIT(ssh->pktin.data+7);
3d63ca2e 1122 int prefix;
1123 strcpy(buf, "Remote debug message: ");
1124 prefix = strlen(buf);
51470298 1125 if (stringlen > (int)(sizeof(buf)-prefix-1))
3d63ca2e 1126 stringlen = sizeof(buf)-prefix-1;
51470298 1127 memcpy(buf + prefix, ssh->pktin.data + 11, stringlen);
3d63ca2e 1128 buf[prefix + stringlen] = '\0';
1129 logevent(buf);
38c4a8da 1130 }
3d63ca2e 1131 goto next_packet; /* FIXME: print the debug message */
1132
1133 /*
1134 * These packets we need do nothing about here.
1135 */
1136 case SSH2_MSG_UNIMPLEMENTED:
1137 case SSH2_MSG_SERVICE_REQUEST:
1138 case SSH2_MSG_SERVICE_ACCEPT:
1139 case SSH2_MSG_KEXINIT:
1140 case SSH2_MSG_NEWKEYS:
1141 case SSH2_MSG_KEXDH_INIT:
1142 case SSH2_MSG_KEXDH_REPLY:
1143 /* case SSH2_MSG_KEX_DH_GEX_REQUEST: duplicate case value */
1144 /* case SSH2_MSG_KEX_DH_GEX_GROUP: duplicate case value */
1145 case SSH2_MSG_KEX_DH_GEX_INIT:
1146 case SSH2_MSG_KEX_DH_GEX_REPLY:
1147 case SSH2_MSG_USERAUTH_REQUEST:
1148 case SSH2_MSG_USERAUTH_FAILURE:
1149 case SSH2_MSG_USERAUTH_SUCCESS:
1150 case SSH2_MSG_USERAUTH_BANNER:
1151 case SSH2_MSG_USERAUTH_PK_OK:
1152 /* case SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: duplicate case value */
1153 /* case SSH2_MSG_USERAUTH_INFO_REQUEST: duplicate case value */
1154 case SSH2_MSG_USERAUTH_INFO_RESPONSE:
1155 case SSH2_MSG_GLOBAL_REQUEST:
1156 case SSH2_MSG_REQUEST_SUCCESS:
1157 case SSH2_MSG_REQUEST_FAILURE:
1158 case SSH2_MSG_CHANNEL_OPEN:
1159 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
1160 case SSH2_MSG_CHANNEL_OPEN_FAILURE:
1161 case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
1162 case SSH2_MSG_CHANNEL_DATA:
1163 case SSH2_MSG_CHANNEL_EXTENDED_DATA:
1164 case SSH2_MSG_CHANNEL_EOF:
1165 case SSH2_MSG_CHANNEL_CLOSE:
1166 case SSH2_MSG_CHANNEL_REQUEST:
1167 case SSH2_MSG_CHANNEL_SUCCESS:
1168 case SSH2_MSG_CHANNEL_FAILURE:
1169 break;
1170
1171 /*
1172 * For anything else we send SSH2_MSG_UNIMPLEMENTED.
1173 */
1174 default:
51470298 1175 ssh2_pkt_init(ssh, SSH2_MSG_UNIMPLEMENTED);
1176 ssh2_pkt_adduint32(ssh, st->incoming_sequence - 1);
1177 ssh2_pkt_send(ssh);
3d63ca2e 1178 break;
38c4a8da 1179 }
1180
e5574168 1181 crFinish(0);
1182}
1183
51470298 1184static void ssh1_pktout_size(Ssh ssh, int len)
32874aea 1185{
374330e2 1186 int pad, biglen;
1187
1188 len += 5; /* type and CRC */
32874aea 1189 pad = 8 - (len % 8);
374330e2 1190 biglen = len + pad;
1191
51470298 1192 ssh->pktout.length = len - 5;
1193 if (ssh->pktout.maxlen < biglen) {
1194 ssh->pktout.maxlen = biglen;
8f203108 1195#ifdef MSCRYPTOAPI
fb09bf1c 1196 /* Allocate enough buffer space for extra block
8f203108 1197 * for MS CryptEncrypt() */
3d88e64d 1198 ssh->pktout.data = sresize(ssh->pktout.data, biglen + 12,
1199 unsigned char);
8f203108 1200#else
3d88e64d 1201 ssh->pktout.data = sresize(ssh->pktout.data, biglen + 4,
1202 unsigned char);
8f203108 1203#endif
374330e2 1204 }
51470298 1205 ssh->pktout.body = ssh->pktout.data + 4 + pad + 1;
4ba9b64b 1206}
374330e2 1207
51470298 1208static void s_wrpkt_start(Ssh ssh, int type, int len)
32874aea 1209{
51470298 1210 ssh1_pktout_size(ssh, len);
1211 ssh->pktout.type = type;
374330e2 1212}
1213
51470298 1214static int s_wrpkt_prepare(Ssh ssh)
32874aea 1215{
fd7a4aad 1216 int pad, biglen, i;
374330e2 1217 unsigned long crc;
fd7a4aad 1218#ifdef __SC__
1219 /*
1220 * XXX various versions of SC (including 8.8.4) screw up the
1221 * register allocation in this function and use the same register
1222 * (D6) for len and as a temporary, with predictable results. The
1223 * following sledgehammer prevents this.
1224 */
1225 volatile
1226#endif
1227 int len;
374330e2 1228
51470298 1229 ssh->pktout.body[-1] = ssh->pktout.type;
4ba9b64b 1230
a8327734 1231 if (ssh->logctx)
1232 log_packet(ssh->logctx, PKT_OUTGOING, ssh->pktout.type,
1233 ssh1_pkt_type(ssh->pktout.type),
1234 ssh->pktout.body, ssh->pktout.length);
00db133f 1235
51470298 1236 if (ssh->v1_compressing) {
4ba9b64b 1237 unsigned char *compblk;
1238 int complen;
5366aed8 1239 zlib_compress_block(ssh->cs_comp_ctx,
1240 ssh->pktout.body - 1, ssh->pktout.length + 1,
4ba9b64b 1241 &compblk, &complen);
51470298 1242 ssh1_pktout_size(ssh, complen - 1);
1243 memcpy(ssh->pktout.body - 1, compblk, complen);
dcbde236 1244 sfree(compblk);
4ba9b64b 1245 }
1246
51470298 1247 len = ssh->pktout.length + 5; /* type and CRC */
32874aea 1248 pad = 8 - (len % 8);
374330e2 1249 biglen = len + pad;
1250
32874aea 1251 for (i = 0; i < pad; i++)
51470298 1252 ssh->pktout.data[i + 4] = random_byte();
71bedafe 1253 crc = crc32_compute(ssh->pktout.data + 4, biglen - 4);
51470298 1254 PUT_32BIT(ssh->pktout.data + biglen, crc);
1255 PUT_32BIT(ssh->pktout.data, len);
374330e2 1256
51470298 1257 if (ssh->cipher)
371e569c 1258 ssh->cipher->encrypt(ssh->v1_cipher_ctx, ssh->pktout.data + 4, biglen);
374330e2 1259
32874aea 1260 return biglen + 4;
39065bed 1261}
1262
51470298 1263static void s_wrpkt(Ssh ssh)
32874aea 1264{
5471d09a 1265 int len, backlog;
51470298 1266 len = s_wrpkt_prepare(ssh);
d8baa528 1267 backlog = sk_write(ssh->s, (char *)ssh->pktout.data, len);
5471d09a 1268 if (backlog > SSH_MAX_BACKLOG)
51470298 1269 ssh_throttle_all(ssh, 1, backlog);
39065bed 1270}
1271
51470298 1272static void s_wrpkt_defer(Ssh ssh)
32874aea 1273{
39065bed 1274 int len;
51470298 1275 len = s_wrpkt_prepare(ssh);
1276 if (ssh->deferred_len + len > ssh->deferred_size) {
1277 ssh->deferred_size = ssh->deferred_len + len + 128;
3d88e64d 1278 ssh->deferred_send_data = sresize(ssh->deferred_send_data,
1279 ssh->deferred_size,
1280 unsigned char);
39065bed 1281 }
51470298 1282 memcpy(ssh->deferred_send_data + ssh->deferred_len, ssh->pktout.data, len);
1283 ssh->deferred_len += len;
374330e2 1284}
1285
fb09bf1c 1286/*
39065bed 1287 * Construct a packet with the specified contents.
fb09bf1c 1288 */
51470298 1289static void construct_packet(Ssh ssh, int pkttype, va_list ap1, va_list ap2)
fb09bf1c 1290{
fb09bf1c 1291 unsigned char *p, *argp, argchar;
1292 unsigned long argint;
1293 int pktlen, argtype, arglen;
7cca0d81 1294 Bignum bn;
fb09bf1c 1295
1296 pktlen = 0;
39065bed 1297 while ((argtype = va_arg(ap1, int)) != PKT_END) {
fb09bf1c 1298 switch (argtype) {
1299 case PKT_INT:
39065bed 1300 (void) va_arg(ap1, int);
fb09bf1c 1301 pktlen += 4;
1302 break;
1303 case PKT_CHAR:
1ec39246 1304 (void) va_arg(ap1, int);
fb09bf1c 1305 pktlen++;
1306 break;
1307 case PKT_DATA:
39065bed 1308 (void) va_arg(ap1, unsigned char *);
1309 arglen = va_arg(ap1, int);
fb09bf1c 1310 pktlen += arglen;
1311 break;
1312 case PKT_STR:
39065bed 1313 argp = va_arg(ap1, unsigned char *);
d8baa528 1314 arglen = strlen((char *)argp);
fb09bf1c 1315 pktlen += 4 + arglen;
1316 break;
7cca0d81 1317 case PKT_BIGNUM:
39065bed 1318 bn = va_arg(ap1, Bignum);
32874aea 1319 pktlen += ssh1_bignum_length(bn);
7cca0d81 1320 break;
fb09bf1c 1321 default:
1322 assert(0);
1323 }
1324 }
fb09bf1c 1325
51470298 1326 s_wrpkt_start(ssh, pkttype, pktlen);
1327 p = ssh->pktout.body;
fb09bf1c 1328
39065bed 1329 while ((argtype = va_arg(ap2, int)) != PKT_END) {
fb09bf1c 1330 switch (argtype) {
1331 case PKT_INT:
39065bed 1332 argint = va_arg(ap2, int);
fb09bf1c 1333 PUT_32BIT(p, argint);
1334 p += 4;
1335 break;
1336 case PKT_CHAR:
1ec39246 1337 argchar = (unsigned char) va_arg(ap2, int);
fb09bf1c 1338 *p = argchar;
1339 p++;
1340 break;
1341 case PKT_DATA:
39065bed 1342 argp = va_arg(ap2, unsigned char *);
1343 arglen = va_arg(ap2, int);
fb09bf1c 1344 memcpy(p, argp, arglen);
1345 p += arglen;
1346 break;
1347 case PKT_STR:
39065bed 1348 argp = va_arg(ap2, unsigned char *);
d8baa528 1349 arglen = strlen((char *)argp);
fb09bf1c 1350 PUT_32BIT(p, arglen);
1351 memcpy(p + 4, argp, arglen);
1352 p += 4 + arglen;
1353 break;
7cca0d81 1354 case PKT_BIGNUM:
39065bed 1355 bn = va_arg(ap2, Bignum);
32874aea 1356 p += ssh1_write_bignum(p, bn);
7cca0d81 1357 break;
fb09bf1c 1358 }
1359 }
39065bed 1360}
fb09bf1c 1361
51470298 1362static void send_packet(Ssh ssh, int pkttype, ...)
32874aea 1363{
39065bed 1364 va_list ap1, ap2;
1365 va_start(ap1, pkttype);
1366 va_start(ap2, pkttype);
51470298 1367 construct_packet(ssh, pkttype, ap1, ap2);
1368 s_wrpkt(ssh);
fb09bf1c 1369}
1370
51470298 1371static void defer_packet(Ssh ssh, int pkttype, ...)
32874aea 1372{
39065bed 1373 va_list ap1, ap2;
1374 va_start(ap1, pkttype);
1375 va_start(ap2, pkttype);
51470298 1376 construct_packet(ssh, pkttype, ap1, ap2);
1377 s_wrpkt_defer(ssh);
39065bed 1378}
1379
32874aea 1380static int ssh_versioncmp(char *a, char *b)
1381{
9697bfd2 1382 char *ae, *be;
1383 unsigned long av, bv;
1384
43aa02a7 1385 av = strtoul(a, &ae, 10);
1386 bv = strtoul(b, &be, 10);
32874aea 1387 if (av != bv)
1388 return (av < bv ? -1 : +1);
1389 if (*ae == '.')
1390 ae++;
1391 if (*be == '.')
1392 be++;
43aa02a7 1393 av = strtoul(ae, &ae, 10);
1394 bv = strtoul(be, &be, 10);
32874aea 1395 if (av != bv)
1396 return (av < bv ? -1 : +1);
9697bfd2 1397 return 0;
1398}
1399
e5574168 1400/*
a92dd380 1401 * Utility routines for putting an SSH-protocol `string' and
1402 * `uint32' into a SHA state.
e5574168 1403 */
1404#include <stdio.h>
32874aea 1405static void sha_string(SHA_State * s, void *str, int len)
1406{
e5574168 1407 unsigned char lenblk[4];
e5574168 1408 PUT_32BIT(lenblk, len);
e5574168 1409 SHA_Bytes(s, lenblk, 4);
e5574168 1410 SHA_Bytes(s, str, len);
1411}
1412
32874aea 1413static void sha_uint32(SHA_State * s, unsigned i)
1414{
a92dd380 1415 unsigned char intblk[4];
1416 PUT_32BIT(intblk, i);
1417 SHA_Bytes(s, intblk, 4);
1418}
1419
7cca0d81 1420/*
1421 * SSH2 packet construction functions.
1422 */
51470298 1423static void ssh2_pkt_ensure(Ssh ssh, int length)
32874aea 1424{
51470298 1425 if (ssh->pktout.maxlen < length) {
1426 ssh->pktout.maxlen = length + 256;
3d88e64d 1427 ssh->pktout.data = sresize(ssh->pktout.data,
1428 ssh->pktout.maxlen + APIEXTRA,
1429 unsigned char);
51470298 1430 if (!ssh->pktout.data)
32874aea 1431 fatalbox("Out of memory");
7cca0d81 1432 }
783415f8 1433}
51470298 1434static void ssh2_pkt_adddata(Ssh ssh, void *data, int len)
32874aea 1435{
51470298 1436 ssh->pktout.length += len;
1437 ssh2_pkt_ensure(ssh, ssh->pktout.length);
1438 memcpy(ssh->pktout.data + ssh->pktout.length - len, data, len);
7cca0d81 1439}
51470298 1440static void ssh2_pkt_addbyte(Ssh ssh, unsigned char byte)
32874aea 1441{
51470298 1442 ssh2_pkt_adddata(ssh, &byte, 1);
7cca0d81 1443}
51470298 1444static void ssh2_pkt_init(Ssh ssh, int pkt_type)
32874aea 1445{
51470298 1446 ssh->pktout.length = 5;
1447 ssh2_pkt_addbyte(ssh, (unsigned char) pkt_type);
7cca0d81 1448}
51470298 1449static void ssh2_pkt_addbool(Ssh ssh, unsigned char value)
32874aea 1450{
51470298 1451 ssh2_pkt_adddata(ssh, &value, 1);
7cca0d81 1452}
51470298 1453static void ssh2_pkt_adduint32(Ssh ssh, unsigned long value)
32874aea 1454{
7cca0d81 1455 unsigned char x[4];
1456 PUT_32BIT(x, value);
51470298 1457 ssh2_pkt_adddata(ssh, x, 4);
7cca0d81 1458}
51470298 1459static void ssh2_pkt_addstring_start(Ssh ssh)
32874aea 1460{
51470298 1461 ssh2_pkt_adduint32(ssh, 0);
1462 ssh->pktout.savedpos = ssh->pktout.length;
7cca0d81 1463}
51470298 1464static void ssh2_pkt_addstring_str(Ssh ssh, char *data)
32874aea 1465{
51470298 1466 ssh2_pkt_adddata(ssh, data, strlen(data));
1467 PUT_32BIT(ssh->pktout.data + ssh->pktout.savedpos - 4,
1468 ssh->pktout.length - ssh->pktout.savedpos);
7cca0d81 1469}
51470298 1470static void ssh2_pkt_addstring_data(Ssh ssh, char *data, int len)
32874aea 1471{
51470298 1472 ssh2_pkt_adddata(ssh, data, len);
1473 PUT_32BIT(ssh->pktout.data + ssh->pktout.savedpos - 4,
1474 ssh->pktout.length - ssh->pktout.savedpos);
7cca0d81 1475}
51470298 1476static void ssh2_pkt_addstring(Ssh ssh, char *data)
32874aea 1477{
51470298 1478 ssh2_pkt_addstring_start(ssh);
1479 ssh2_pkt_addstring_str(ssh, data);
7cca0d81 1480}
d8baa528 1481static unsigned char *ssh2_mpint_fmt(Bignum b, int *len)
32874aea 1482{
7cca0d81 1483 unsigned char *p;
32874aea 1484 int i, n = (bignum_bitcount(b) + 7) / 8;
3d88e64d 1485 p = snewn(n + 1, unsigned char);
7cca0d81 1486 if (!p)
32874aea 1487 fatalbox("out of memory");
7cca0d81 1488 p[0] = 0;
3709bfe9 1489 for (i = 1; i <= n; i++)
32874aea 1490 p[i] = bignum_byte(b, n - i);
7cca0d81 1491 i = 0;
32874aea 1492 while (i <= n && p[i] == 0 && (p[i + 1] & 0x80) == 0)
1493 i++;
1494 memmove(p, p + i, n + 1 - i);
1495 *len = n + 1 - i;
7cca0d81 1496 return p;
1497}
51470298 1498static void ssh2_pkt_addmp(Ssh ssh, Bignum b)
32874aea 1499{
7cca0d81 1500 unsigned char *p;
1501 int len;
1502 p = ssh2_mpint_fmt(b, &len);
51470298 1503 ssh2_pkt_addstring_start(ssh);
d8baa528 1504 ssh2_pkt_addstring_data(ssh, (char *)p, len);
dcbde236 1505 sfree(p);
7cca0d81 1506}
b185170a 1507
1508/*
1509 * Construct an SSH2 final-form packet: compress it, encrypt it,
1510 * put the MAC on it. Final packet, ready to be sent, is stored in
51470298 1511 * ssh->pktout.data. Total length is returned.
b185170a 1512 */
51470298 1513static int ssh2_pkt_construct(Ssh ssh)
32874aea 1514{
7cca0d81 1515 int cipherblk, maclen, padding, i;
7cca0d81 1516
a8327734 1517 if (ssh->logctx)
1518 log_packet(ssh->logctx, PKT_OUTGOING, ssh->pktout.data[5],
1519 ssh2_pkt_type(ssh->pkt_ctx, ssh->pktout.data[5]),
1520 ssh->pktout.data + 6, ssh->pktout.length - 6);
00db133f 1521
7cca0d81 1522 /*
4ba9b64b 1523 * Compress packet payload.
1524 */
4ba9b64b 1525 {
1526 unsigned char *newpayload;
1527 int newlen;
51470298 1528 if (ssh->cscomp &&
5366aed8 1529 ssh->cscomp->compress(ssh->cs_comp_ctx, ssh->pktout.data + 5,
1530 ssh->pktout.length - 5,
51470298 1531 &newpayload, &newlen)) {
1532 ssh->pktout.length = 5;
1533 ssh2_pkt_adddata(ssh, newpayload, newlen);
dcbde236 1534 sfree(newpayload);
4ba9b64b 1535 }
1536 }
1537
1538 /*
7cca0d81 1539 * Add padding. At least four bytes, and must also bring total
1540 * length (minus MAC) up to a multiple of the block size.
1541 */
51470298 1542 cipherblk = ssh->cscipher ? ssh->cscipher->blksize : 8; /* block size */
32874aea 1543 cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
7cca0d81 1544 padding = 4;
32874aea 1545 padding +=
51470298 1546 (cipherblk - (ssh->pktout.length + padding) % cipherblk) % cipherblk;
1547 maclen = ssh->csmac ? ssh->csmac->len : 0;
1548 ssh2_pkt_ensure(ssh, ssh->pktout.length + padding + maclen);
1549 ssh->pktout.data[4] = padding;
7cca0d81 1550 for (i = 0; i < padding; i++)
51470298 1551 ssh->pktout.data[ssh->pktout.length + i] = random_byte();
1552 PUT_32BIT(ssh->pktout.data, ssh->pktout.length + padding - 4);
1553 if (ssh->csmac)
e0e1a00d 1554 ssh->csmac->generate(ssh->cs_mac_ctx, ssh->pktout.data,
1555 ssh->pktout.length + padding,
51470298 1556 ssh->v2_outgoing_sequence);
1557 ssh->v2_outgoing_sequence++; /* whether or not we MACed */
1558
1559 if (ssh->cscipher)
371e569c 1560 ssh->cscipher->encrypt(ssh->cs_cipher_ctx,
1561 ssh->pktout.data, ssh->pktout.length + padding);
51470298 1562
1563 /* Ready-to-send packet starts at ssh->pktout.data. We return length. */
1564 return ssh->pktout.length + padding + maclen;
b185170a 1565}
1566
1567/*
1568 * Construct and send an SSH2 packet immediately.
1569 */
51470298 1570static void ssh2_pkt_send(Ssh ssh)
32874aea 1571{
5471d09a 1572 int len;
1573 int backlog;
51470298 1574 len = ssh2_pkt_construct(ssh);
d8baa528 1575 backlog = sk_write(ssh->s, (char *)ssh->pktout.data, len);
5471d09a 1576 if (backlog > SSH_MAX_BACKLOG)
51470298 1577 ssh_throttle_all(ssh, 1, backlog);
b185170a 1578}
1579
1580/*
1581 * Construct an SSH2 packet and add it to a deferred data block.
1582 * Useful for sending multiple packets in a single sk_write() call,
1583 * to prevent a traffic-analysing listener from being able to work
1584 * out the length of any particular packet (such as the password
1585 * packet).
1586 *
1587 * Note that because SSH2 sequence-numbers its packets, this can
1588 * NOT be used as an m4-style `defer' allowing packets to be
1589 * constructed in one order and sent in another.
1590 */
51470298 1591static void ssh2_pkt_defer(Ssh ssh)
32874aea 1592{
51470298 1593 int len = ssh2_pkt_construct(ssh);
1594 if (ssh->deferred_len + len > ssh->deferred_size) {
1595 ssh->deferred_size = ssh->deferred_len + len + 128;
3d88e64d 1596 ssh->deferred_send_data = sresize(ssh->deferred_send_data,
1597 ssh->deferred_size,
1598 unsigned char);
b185170a 1599 }
51470298 1600 memcpy(ssh->deferred_send_data + ssh->deferred_len, ssh->pktout.data, len);
1601 ssh->deferred_len += len;
b185170a 1602}
1603
1604/*
1605 * Send the whole deferred data block constructed by
39065bed 1606 * ssh2_pkt_defer() or SSH1's defer_packet().
b185170a 1607 */
51470298 1608static void ssh_pkt_defersend(Ssh ssh)
32874aea 1609{
5471d09a 1610 int backlog;
d8baa528 1611 backlog = sk_write(ssh->s, (char *)ssh->deferred_send_data,
1612 ssh->deferred_len);
51470298 1613 ssh->deferred_len = ssh->deferred_size = 0;
1614 sfree(ssh->deferred_send_data);
1615 ssh->deferred_send_data = NULL;
5471d09a 1616 if (backlog > SSH_MAX_BACKLOG)
51470298 1617 ssh_throttle_all(ssh, 1, backlog);
7cca0d81 1618}
1619
1620#if 0
32874aea 1621void bndebug(char *string, Bignum b)
1622{
7cca0d81 1623 unsigned char *p;
1624 int i, len;
1625 p = ssh2_mpint_fmt(b, &len);
1626 debug(("%s", string));
1627 for (i = 0; i < len; i++)
32874aea 1628 debug((" %02x", p[i]));
765c4200 1629 debug(("\n"));
dcbde236 1630 sfree(p);
7cca0d81 1631}
1632#endif
1633
32874aea 1634static void sha_mpint(SHA_State * s, Bignum b)
1635{
7cca0d81 1636 unsigned char *p;
1637 int len;
1638 p = ssh2_mpint_fmt(b, &len);
1639 sha_string(s, p, len);
dcbde236 1640 sfree(p);
7cca0d81 1641}
1642
1643/*
0016d70b 1644 * Packet decode functions for both SSH1 and SSH2.
7cca0d81 1645 */
0016d70b 1646static unsigned long ssh_pkt_getuint32(Ssh ssh)
32874aea 1647{
7cca0d81 1648 unsigned long value;
51470298 1649 if (ssh->pktin.length - ssh->pktin.savedpos < 4)
32874aea 1650 return 0; /* arrgh, no way to decline (FIXME?) */
0016d70b 1651 value = GET_32BIT(ssh->pktin.body + ssh->pktin.savedpos);
51470298 1652 ssh->pktin.savedpos += 4;
7cca0d81 1653 return value;
1654}
51470298 1655static int ssh2_pkt_getbool(Ssh ssh)
32874aea 1656{
65a22376 1657 unsigned long value;
51470298 1658 if (ssh->pktin.length - ssh->pktin.savedpos < 1)
32874aea 1659 return 0; /* arrgh, no way to decline (FIXME?) */
0016d70b 1660 value = ssh->pktin.body[ssh->pktin.savedpos] != 0;
51470298 1661 ssh->pktin.savedpos++;
65a22376 1662 return value;
1663}
0016d70b 1664static void ssh_pkt_getstring(Ssh ssh, char **p, int *length)
32874aea 1665{
57356d63 1666 int len;
7cca0d81 1667 *p = NULL;
45068b27 1668 *length = 0;
51470298 1669 if (ssh->pktin.length - ssh->pktin.savedpos < 4)
32874aea 1670 return;
0016d70b 1671 len = GET_32BIT(ssh->pktin.body + ssh->pktin.savedpos);
57356d63 1672 if (len < 0)
1673 return;
1674 *length = len;
51470298 1675 ssh->pktin.savedpos += 4;
1676 if (ssh->pktin.length - ssh->pktin.savedpos < *length)
32874aea 1677 return;
0016d70b 1678 *p = (char *)(ssh->pktin.body + ssh->pktin.savedpos);
51470298 1679 ssh->pktin.savedpos += *length;
7cca0d81 1680}
0016d70b 1681static void *ssh_pkt_getdata(Ssh ssh, int length)
1682{
1683 if (ssh->pktin.length - ssh->pktin.savedpos < length)
1684 return NULL;
1685 ssh->pktin.savedpos += length;
1686 return ssh->pktin.body + (ssh->pktin.savedpos - length);
1687}
1688static int ssh1_pkt_getrsakey(Ssh ssh, struct RSAKey *key,
1689 unsigned char **keystr)
1690{
1691 int j;
1692
1693 j = makekey(ssh->pktin.body + ssh->pktin.savedpos,
1694 ssh->pktin.length - ssh->pktin.savedpos,
1695 key, keystr, 0);
1696
1697 if (j < 0)
1698 return FALSE;
1699
1700 ssh->pktin.savedpos += j;
1701 assert(ssh->pktin.savedpos < ssh->pktin.length);
1702
1703 return TRUE;
1704}
1705static Bignum ssh1_pkt_getmp(Ssh ssh)
1706{
1707 int j;
1708 Bignum b;
1709
1710 j = ssh1_read_bignum(ssh->pktin.body + ssh->pktin.savedpos,
1711 ssh->pktin.length - ssh->pktin.savedpos, &b);
1712
1713 if (j < 0)
1714 return NULL;
1715
1716 ssh->pktin.savedpos += j;
1717 return b;
1718}
51470298 1719static Bignum ssh2_pkt_getmp(Ssh ssh)
32874aea 1720{
7cca0d81 1721 char *p;
3709bfe9 1722 int length;
7cca0d81 1723 Bignum b;
1724
0016d70b 1725 ssh_pkt_getstring(ssh, &p, &length);
7cca0d81 1726 if (!p)
32874aea 1727 return NULL;
8d5de777 1728 if (p[0] & 0x80) {
6b5cf8b4 1729 bombout(("internal error: Can't handle negative mpints"));
32874aea 1730 return NULL;
8d5de777 1731 }
d8baa528 1732 b = bignum_from_bytes((unsigned char *)p, length);
7cca0d81 1733 return b;
1734}
1735
7d503c31 1736/*
1dd353b5 1737 * Helper function to add an SSH2 signature blob to a packet.
1738 * Expects to be shown the public key blob as well as the signature
1739 * blob. Normally works just like ssh2_pkt_addstring, but will
1740 * fiddle with the signature packet if necessary for
1741 * BUG_SSH2_RSA_PADDING.
1742 */
51470298 1743static void ssh2_add_sigblob(Ssh ssh, void *pkblob_v, int pkblob_len,
1dd353b5 1744 void *sigblob_v, int sigblob_len)
1745{
1746 unsigned char *pkblob = (unsigned char *)pkblob_v;
1747 unsigned char *sigblob = (unsigned char *)sigblob_v;
1748
1749 /* dmemdump(pkblob, pkblob_len); */
1750 /* dmemdump(sigblob, sigblob_len); */
1751
1752 /*
1753 * See if this is in fact an ssh-rsa signature and a buggy
1754 * server; otherwise we can just do this the easy way.
1755 */
51470298 1756 if ((ssh->remote_bugs & BUG_SSH2_RSA_PADDING) &&
1dd353b5 1757 (GET_32BIT(pkblob) == 7 && !memcmp(pkblob+4, "ssh-rsa", 7))) {
1758 int pos, len, siglen;
1759
1760 /*
1761 * Find the byte length of the modulus.
1762 */
1763
1764 pos = 4+7; /* skip over "ssh-rsa" */
1765 pos += 4 + GET_32BIT(pkblob+pos); /* skip over exponent */
1766 len = GET_32BIT(pkblob+pos); /* find length of modulus */
1767 pos += 4; /* find modulus itself */
1768 while (len > 0 && pkblob[pos] == 0)
1769 len--, pos++;
1770 /* debug(("modulus length is %d\n", len)); */
1771
1772 /*
1773 * Now find the signature integer.
1774 */
1775 pos = 4+7; /* skip over "ssh-rsa" */
1776 siglen = GET_32BIT(sigblob+pos);
1777 /* debug(("signature length is %d\n", siglen)); */
1778
1779 if (len != siglen) {
1780 unsigned char newlen[4];
51470298 1781 ssh2_pkt_addstring_start(ssh);
d8baa528 1782 ssh2_pkt_addstring_data(ssh, (char *)sigblob, pos);
1dd353b5 1783 /* dmemdump(sigblob, pos); */
1784 pos += 4; /* point to start of actual sig */
1785 PUT_32BIT(newlen, len);
d8baa528 1786 ssh2_pkt_addstring_data(ssh, (char *)newlen, 4);
1dd353b5 1787 /* dmemdump(newlen, 4); */
1788 newlen[0] = 0;
1789 while (len-- > siglen) {
d8baa528 1790 ssh2_pkt_addstring_data(ssh, (char *)newlen, 1);
1dd353b5 1791 /* dmemdump(newlen, 1); */
1792 }
d8baa528 1793 ssh2_pkt_addstring_data(ssh, (char *)(sigblob+pos), siglen);
1dd353b5 1794 /* dmemdump(sigblob+pos, siglen); */
1795 return;
1796 }
1797
1798 /* Otherwise fall through and do it the easy way. */
1799 }
1800
51470298 1801 ssh2_pkt_addstring_start(ssh);
d8baa528 1802 ssh2_pkt_addstring_data(ssh, (char *)sigblob, sigblob_len);
1dd353b5 1803}
1804
1805/*
7d503c31 1806 * Examine the remote side's version string and compare it against
1807 * a list of known buggy implementations.
1808 */
51470298 1809static void ssh_detect_bugs(Ssh ssh, char *vstring)
32874aea 1810{
1811 char *imp; /* pointer to implementation part */
7d503c31 1812 imp = vstring;
1813 imp += strcspn(imp, "-");
bd358db1 1814 if (*imp) imp++;
7d503c31 1815 imp += strcspn(imp, "-");
bd358db1 1816 if (*imp) imp++;
7d503c31 1817
51470298 1818 ssh->remote_bugs = 0;
7d503c31 1819
5ecd7ad0 1820 if (ssh->cfg.sshbug_ignore1 == FORCE_ON ||
1821 (ssh->cfg.sshbug_ignore1 == AUTO &&
2c9c6388 1822 (!strcmp(imp, "1.2.18") || !strcmp(imp, "1.2.19") ||
1823 !strcmp(imp, "1.2.20") || !strcmp(imp, "1.2.21") ||
46ac09aa 1824 !strcmp(imp, "1.2.22") || !strcmp(imp, "Cisco-1.25") ||
1825 !strcmp(imp, "OSU_1.4alpha3")))) {
32874aea 1826 /*
1827 * These versions don't support SSH1_MSG_IGNORE, so we have
1828 * to use a different defence against password length
1829 * sniffing.
1830 */
51470298 1831 ssh->remote_bugs |= BUG_CHOKES_ON_SSH1_IGNORE;
32874aea 1832 logevent("We believe remote version has SSH1 ignore bug");
7d503c31 1833 }
1834
5ecd7ad0 1835 if (ssh->cfg.sshbug_plainpw1 == FORCE_ON ||
1836 (ssh->cfg.sshbug_plainpw1 == AUTO &&
46ac09aa 1837 (!strcmp(imp, "Cisco-1.25") || !strcmp(imp, "OSU_1.4alpha3")))) {
bd358db1 1838 /*
1839 * These versions need a plain password sent; they can't
1840 * handle having a null and a random length of data after
1841 * the password.
1842 */
51470298 1843 ssh->remote_bugs |= BUG_NEEDS_SSH1_PLAIN_PASSWORD;
bd358db1 1844 logevent("We believe remote version needs a plain SSH1 password");
1845 }
1846
5ecd7ad0 1847 if (ssh->cfg.sshbug_rsa1 == FORCE_ON ||
1848 (ssh->cfg.sshbug_rsa1 == AUTO &&
2c9c6388 1849 (!strcmp(imp, "Cisco-1.25")))) {
0df73905 1850 /*
1851 * These versions apparently have no clue whatever about
1852 * RSA authentication and will panic and die if they see
1853 * an AUTH_RSA message.
1854 */
51470298 1855 ssh->remote_bugs |= BUG_CHOKES_ON_RSA;
0df73905 1856 logevent("We believe remote version can't handle RSA authentication");
1857 }
1858
5ecd7ad0 1859 if (ssh->cfg.sshbug_hmac2 == FORCE_ON ||
1860 (ssh->cfg.sshbug_hmac2 == AUTO &&
b9f387af 1861 !wc_match("* VShell", imp) &&
831301f6 1862 (wc_match("2.1.0*", imp) || wc_match("2.0.*", imp) ||
1863 wc_match("2.2.0*", imp) || wc_match("2.3.0*", imp) ||
1864 wc_match("2.1 *", imp)))) {
32874aea 1865 /*
1866 * These versions have the HMAC bug.
1867 */
51470298 1868 ssh->remote_bugs |= BUG_SSH2_HMAC;
32874aea 1869 logevent("We believe remote version has SSH2 HMAC bug");
7d503c31 1870 }
1dd353b5 1871
5ecd7ad0 1872 if (ssh->cfg.sshbug_derivekey2 == FORCE_ON ||
1873 (ssh->cfg.sshbug_derivekey2 == AUTO &&
b9f387af 1874 !wc_match("* VShell", imp) &&
2856a1b9 1875 (wc_match("2.0.0*", imp) || wc_match("2.0.10*", imp) ))) {
088bde77 1876 /*
1877 * These versions have the key-derivation bug (failing to
1878 * include the literal shared secret in the hashes that
1879 * generate the keys).
1880 */
51470298 1881 ssh->remote_bugs |= BUG_SSH2_DERIVEKEY;
088bde77 1882 logevent("We believe remote version has SSH2 key-derivation bug");
1883 }
1884
5ecd7ad0 1885 if (ssh->cfg.sshbug_rsapad2 == FORCE_ON ||
1886 (ssh->cfg.sshbug_rsapad2 == AUTO &&
831301f6 1887 (wc_match("OpenSSH_2.[5-9]*", imp) ||
1888 wc_match("OpenSSH_3.[0-2]*", imp)))) {
1dd353b5 1889 /*
1890 * These versions have the SSH2 RSA padding bug.
1891 */
51470298 1892 ssh->remote_bugs |= BUG_SSH2_RSA_PADDING;
1dd353b5 1893 logevent("We believe remote version has SSH2 RSA padding bug");
1894 }
8e975795 1895
dda87a28 1896 if (ssh->cfg.sshbug_pksessid2 == FORCE_ON ||
1897 (ssh->cfg.sshbug_pksessid2 == AUTO &&
1898 wc_match("OpenSSH_2.[0-2]*", imp))) {
1899 /*
1900 * These versions have the SSH2 session-ID bug in
1901 * public-key authentication.
1902 */
1903 ssh->remote_bugs |= BUG_SSH2_PK_SESSIONID;
1904 logevent("We believe remote version has SSH2 public-key-session-ID bug");
1905 }
1906
5ecd7ad0 1907 if (ssh->cfg.sshbug_dhgex2 == FORCE_ON) {
8e975795 1908 /*
831301f6 1909 * User specified the SSH2 DH GEX bug.
8e975795 1910 */
51470298 1911 ssh->remote_bugs |= BUG_SSH2_DH_GEX;
8e975795 1912 logevent("We believe remote version has SSH2 DH group exchange bug");
1913 }
7d503c31 1914}
1915
51470298 1916static int do_ssh_init(Ssh ssh, unsigned char c)
32874aea 1917{
51470298 1918 struct do_ssh_init_state {
1919 int vslen;
1920 char version[10];
1921 char *vstring;
1922 int vstrsize;
1923 int i;
1924 int proto1, proto2;
1925 };
1926 crState(do_ssh_init_state);
374330e2 1927
51470298 1928 crBegin(ssh->do_ssh_init_crstate);
8df7a775 1929
1930 /* Search for the string "SSH-" in the input. */
51470298 1931 s->i = 0;
8df7a775 1932 while (1) {
1933 static const int transS[] = { 1, 2, 2, 1 };
1934 static const int transH[] = { 0, 0, 3, 0 };
1935 static const int transminus[] = { 0, 0, 0, -1 };
32874aea 1936 if (c == 'S')
51470298 1937 s->i = transS[s->i];
32874aea 1938 else if (c == 'H')
51470298 1939 s->i = transH[s->i];
32874aea 1940 else if (c == '-')
51470298 1941 s->i = transminus[s->i];
32874aea 1942 else
51470298 1943 s->i = 0;
1944 if (s->i < 0)
8df7a775 1945 break;
1946 crReturn(1); /* get another character */
374330e2 1947 }
8df7a775 1948
51470298 1949 s->vstrsize = 16;
3d88e64d 1950 s->vstring = snewn(s->vstrsize, char);
51470298 1951 strcpy(s->vstring, "SSH-");
1952 s->vslen = 4;
1953 s->i = 0;
374330e2 1954 while (1) {
8df7a775 1955 crReturn(1); /* get another char */
51470298 1956 if (s->vslen >= s->vstrsize - 1) {
1957 s->vstrsize += 16;
3d88e64d 1958 s->vstring = sresize(s->vstring, s->vstrsize, char);
32874aea 1959 }
51470298 1960 s->vstring[s->vslen++] = c;
1961 if (s->i >= 0) {
374330e2 1962 if (c == '-') {
51470298 1963 s->version[s->i] = '\0';
1964 s->i = -1;
1965 } else if (s->i < sizeof(s->version) - 1)
1966 s->version[s->i++] = c;
c4ffc4d0 1967 } else if (c == '\012')
374330e2 1968 break;
1969 }
1970
51470298 1971 ssh->agentfwd_enabled = FALSE;
1972 ssh->rdpkt2_state.incoming_sequence = 0;
960e736a 1973
51470298 1974 s->vstring[s->vslen] = 0;
1975 s->vstring[strcspn(s->vstring, "\r\n")] = '\0';/* remove EOL chars */
1976 {
1977 char *vlog;
3d88e64d 1978 vlog = snewn(20 + s->vslen, char);
51470298 1979 sprintf(vlog, "Server version: %s", s->vstring);
1980 logevent(vlog);
1981 sfree(vlog);
1982 }
1983 ssh_detect_bugs(ssh, s->vstring);
c5e9c988 1984
adf799dd 1985 /*
38d228a2 1986 * Decide which SSH protocol version to support.
adf799dd 1987 */
38d228a2 1988
1989 /* Anything strictly below "2.0" means protocol 1 is supported. */
51470298 1990 s->proto1 = ssh_versioncmp(s->version, "2.0") < 0;
38d228a2 1991 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
51470298 1992 s->proto2 = ssh_versioncmp(s->version, "1.99") >= 0;
38d228a2 1993
86916870 1994 if (ssh->cfg.sshprot == 0 && !s->proto1) {
6b5cf8b4 1995 bombout(("SSH protocol version 1 required by user but not provided by server"));
7ffdbc1a 1996 crStop(0);
38d228a2 1997 }
86916870 1998 if (ssh->cfg.sshprot == 3 && !s->proto2) {
6b5cf8b4 1999 bombout(("SSH protocol version 2 required by user but not provided by server"));
7ffdbc1a 2000 crStop(0);
38d228a2 2001 }
2002
86916870 2003 if (s->proto2 && (ssh->cfg.sshprot >= 2 || !s->proto1)) {
32874aea 2004 /*
38d228a2 2005 * Use v2 protocol.
32874aea 2006 */
2007 char verstring[80], vlog[100];
2008 sprintf(verstring, "SSH-2.0-%s", sshver);
51470298 2009 SHA_Init(&ssh->exhashbase);
32874aea 2010 /*
2011 * Hash our version string and their version string.
2012 */
51470298 2013 sha_string(&ssh->exhashbase, verstring, strlen(verstring));
2014 sha_string(&ssh->exhashbase, s->vstring, strcspn(s->vstring, "\r\n"));
32874aea 2015 sprintf(vlog, "We claim version: %s", verstring);
2016 logevent(vlog);
c4ffc4d0 2017 strcat(verstring, "\012");
32874aea 2018 logevent("Using SSH protocol version 2");
51470298 2019 sk_write(ssh->s, verstring, strlen(verstring));
2020 ssh->protocol = ssh2_protocol;
2021 ssh->version = 2;
2022 ssh->s_rdpkt = ssh2_rdpkt;
e5574168 2023 } else {
32874aea 2024 /*
38d228a2 2025 * Use v1 protocol.
32874aea 2026 */
2027 char verstring[80], vlog[100];
2028 sprintf(verstring, "SSH-%s-%s",
51470298 2029 (ssh_versioncmp(s->version, "1.5") <= 0 ? s->version : "1.5"),
32874aea 2030 sshver);
2031 sprintf(vlog, "We claim version: %s", verstring);
2032 logevent(vlog);
c4ffc4d0 2033 strcat(verstring, "\012");
759712a6 2034
32874aea 2035 logevent("Using SSH protocol version 1");
51470298 2036 sk_write(ssh->s, verstring, strlen(verstring));
2037 ssh->protocol = ssh1_protocol;
2038 ssh->version = 1;
2039 ssh->s_rdpkt = ssh1_rdpkt;
e5574168 2040 }
125105d1 2041 update_specials_menu(ssh->frontend);
51470298 2042 ssh->state = SSH_STATE_BEFORE_SIZE;
8df7a775 2043
51470298 2044 sfree(s->vstring);
50526e47 2045
8df7a775 2046 crFinish(0);
2047}
2048
51470298 2049static void ssh_gotdata(Ssh ssh, unsigned char *data, int datalen)
8df7a775 2050{
51470298 2051 crBegin(ssh->ssh_gotdata_crstate);
8df7a775 2052
2053 /*
2054 * To begin with, feed the characters one by one to the
2055 * protocol initialisation / selection function do_ssh_init().
2056 * When that returns 0, we're done with the initial greeting
2057 * exchange and can move on to packet discipline.
2058 */
2059 while (1) {
51470298 2060 int ret; /* need not be kept across crReturn */
8df7a775 2061 if (datalen == 0)
2062 crReturnV; /* more data please */
51470298 2063 ret = do_ssh_init(ssh, *data);
32874aea 2064 data++;
2065 datalen--;
8df7a775 2066 if (ret == 0)
2067 break;
2068 }
2069
2070 /*
2071 * We emerge from that loop when the initial negotiation is
2072 * over and we have selected an s_rdpkt function. Now pass
2073 * everything to s_rdpkt, and then pass the resulting packets
2074 * to the proper protocol handler.
2075 */
2076 if (datalen == 0)
2077 crReturnV;
2078 while (1) {
2079 while (datalen > 0) {
51470298 2080 if (ssh->s_rdpkt(ssh, &data, &datalen) == 0) {
2081 if (ssh->state == SSH_STATE_CLOSED) {
e14d0f19 2082 return;
2083 }
51470298 2084 ssh->protocol(ssh, NULL, 0, 1);
2085 if (ssh->state == SSH_STATE_CLOSED) {
8df7a775 2086 return;
2087 }
2088 }
2089 }
2090 crReturnV;
2091 }
2092 crFinishV;
2093}
2094
36f94d1f 2095static void ssh_do_close(Ssh ssh)
32874aea 2096{
36f94d1f 2097 int i;
2098 struct ssh_channel *c;
2099
51470298 2100 ssh->state = SSH_STATE_CLOSED;
2101 if (ssh->s) {
2102 sk_close(ssh->s);
2103 ssh->s = NULL;
f3ab576e 2104 }
36f94d1f 2105 /*
2106 * Now we must shut down any port and X forwardings going
2107 * through this connection.
2108 */
74a98066 2109 if (ssh->channels) {
2110 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
2111 switch (c->type) {
2112 case CHAN_X11:
2113 x11_close(c->u.x11.s);
2114 break;
2115 case CHAN_SOCKDATA:
2116 pfd_close(c->u.pfd.s);
2117 break;
2118 }
2119 del234(ssh->channels, c);
2120 if (ssh->version == 2)
2121 bufchain_clear(&c->v.v2.outbuffer);
2122 sfree(c);
36f94d1f 2123 }
36f94d1f 2124 }
2125}
2126
cbe2d68f 2127static int ssh_closing(Plug plug, const char *error_msg, int error_code,
36f94d1f 2128 int calling_back)
2129{
2130 Ssh ssh = (Ssh) plug;
2131 ssh_do_close(ssh);
7e78000d 2132 if (error_msg) {
32874aea 2133 /* A socket error has occurred. */
247308b5 2134 logevent(error_msg);
971bcc0a 2135 connection_fatal(ssh->frontend, "%s", error_msg);
7e78000d 2136 } else {
2137 /* Otherwise, the remote side closed the connection normally. */
8df7a775 2138 }
7e78000d 2139 return 0;
2140}
2141
32874aea 2142static int ssh_receive(Plug plug, int urgent, char *data, int len)
2143{
51470298 2144 Ssh ssh = (Ssh) plug;
d8baa528 2145 ssh_gotdata(ssh, (unsigned char *)data, len);
51470298 2146 if (ssh->state == SSH_STATE_CLOSED) {
36f94d1f 2147 ssh_do_close(ssh);
32874aea 2148 return 0;
3257deae 2149 }
fef97f43 2150 return 1;
374330e2 2151}
2152
5471d09a 2153static void ssh_sent(Plug plug, int bufsize)
2154{
51470298 2155 Ssh ssh = (Ssh) plug;
5471d09a 2156 /*
2157 * If the send backlog on the SSH socket itself clears, we
2158 * should unthrottle the whole world if it was throttled.
2159 */
2160 if (bufsize < SSH_MAX_BACKLOG)
51470298 2161 ssh_throttle_all(ssh, 0, bufsize);
5471d09a 2162}
2163
fb09bf1c 2164/*
8df7a775 2165 * Connect to specified host and port.
2166 * Returns an error message, or NULL on success.
6e1ebb76 2167 * Also places the canonical host name into `realhost'. It must be
2168 * freed by the caller.
8df7a775 2169 */
cbe2d68f 2170static const char *connect_to_host(Ssh ssh, char *host, int port,
79bf227b 2171 char **realhost, int nodelay, int keepalive)
8df7a775 2172{
51470298 2173 static const struct plug_function_table fn_table = {
7e78000d 2174 ssh_closing,
5471d09a 2175 ssh_receive,
2176 ssh_sent,
2177 NULL
51470298 2178 };
7e78000d 2179
8df7a775 2180 SockAddr addr;
cbe2d68f 2181 const char *err;
8df7a775 2182
3d88e64d 2183 ssh->savedhost = snewn(1 + strlen(host), char);
51470298 2184 if (!ssh->savedhost)
8df7a775 2185 fatalbox("Out of memory");
51470298 2186 strcpy(ssh->savedhost, host);
8df7a775 2187
2188 if (port < 0)
2189 port = 22; /* default ssh port */
51470298 2190 ssh->savedport = port;
8df7a775 2191
2192 /*
2193 * Try to find host.
2194 */
57356d63 2195 logeventf(ssh, "Looking up host \"%s\"", host);
e8fa8f62 2196 addr = name_lookup(host, port, realhost, &ssh->cfg);
170c1e6e 2197 if ((err = sk_addr_error(addr)) != NULL) {
2198 sk_addr_free(addr);
8df7a775 2199 return err;
170c1e6e 2200 }
8df7a775 2201
8df7a775 2202 /*
2203 * Open socket.
2204 */
3ad9d396 2205 {
57356d63 2206 char addrbuf[100];
3ad9d396 2207 sk_getaddr(addr, addrbuf, 100);
57356d63 2208 logeventf(ssh, "Connecting to %s port %d", addrbuf, port);
3ad9d396 2209 }
51470298 2210 ssh->fn = &fn_table;
e8fa8f62 2211 ssh->s = new_connection(addr, *realhost, port,
79bf227b 2212 0, 1, nodelay, keepalive, (Plug) ssh, &ssh->cfg);
70e5d0fd 2213 if ((err = sk_socket_error(ssh->s)) != NULL) {
51470298 2214 ssh->s = NULL;
8df7a775 2215 return err;
67c4ba2e 2216 }
8df7a775 2217
8df7a775 2218 return NULL;
2219}
2220
2221/*
5471d09a 2222 * Throttle or unthrottle the SSH connection.
2223 */
51470298 2224static void ssh1_throttle(Ssh ssh, int adjust)
5471d09a 2225{
51470298 2226 int old_count = ssh->v1_throttle_count;
2227 ssh->v1_throttle_count += adjust;
2228 assert(ssh->v1_throttle_count >= 0);
2229 if (ssh->v1_throttle_count && !old_count) {
2230 sk_set_frozen(ssh->s, 1);
2231 } else if (!ssh->v1_throttle_count && old_count) {
2232 sk_set_frozen(ssh->s, 0);
5471d09a 2233 }
2234}
2235
2236/*
2237 * Throttle or unthrottle _all_ local data streams (for when sends
2238 * on the SSH connection itself back up).
2239 */
51470298 2240static void ssh_throttle_all(Ssh ssh, int enable, int bufsize)
5471d09a 2241{
2242 int i;
2243 struct ssh_channel *c;
2244
51470298 2245 if (enable == ssh->throttled_all)
5471d09a 2246 return;
51470298 2247 ssh->throttled_all = enable;
2248 ssh->overall_bufsize = bufsize;
2249 if (!ssh->channels)
5471d09a 2250 return;
51470298 2251 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
5471d09a 2252 switch (c->type) {
2253 case CHAN_MAINSESSION:
2254 /*
2255 * This is treated separately, outside the switch.
2256 */
2257 break;
2258 case CHAN_X11:
2259 x11_override_throttle(c->u.x11.s, enable);
2260 break;
2261 case CHAN_AGENT:
2262 /* Agent channels require no buffer management. */
2263 break;
2264 case CHAN_SOCKDATA:
36f94d1f 2265 pfd_override_throttle(c->u.pfd.s, enable);
5471d09a 2266 break;
2267 }
2268 }
2269}
2270
2271/*
51470298 2272 * Username and password input, abstracted off into routines
2273 * reusable in several places - even between SSH1 and SSH2.
0405e71f 2274 */
0405e71f 2275
2276/* Set up a username or password input loop on a given buffer. */
ae9ae89f 2277static void setup_userpass_input(Ssh ssh, char *buffer, int buflen, int echo)
0405e71f 2278{
51470298 2279 ssh->userpass_input_buffer = buffer;
2280 ssh->userpass_input_buflen = buflen;
2281 ssh->userpass_input_bufpos = 0;
2282 ssh->userpass_input_echo = echo;
0405e71f 2283}
2284
2285/*
2286 * Process some terminal data in the course of username/password
2287 * input. Returns >0 for success (line of input returned in
2288 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2289 * for inconclusive (keep waiting for more input please).
2290 */
ae9ae89f 2291static int process_userpass_input(Ssh ssh, unsigned char *in, int inlen)
0405e71f 2292{
2293 char c;
2294
2295 while (inlen--) {
2296 switch (c = *in++) {
2297 case 10:
2298 case 13:
51470298 2299 ssh->userpass_input_buffer[ssh->userpass_input_bufpos] = 0;
2300 ssh->userpass_input_buffer[ssh->userpass_input_buflen-1] = 0;
0405e71f 2301 return +1;
2302 break;
2303 case 8:
2304 case 127:
51470298 2305 if (ssh->userpass_input_bufpos > 0) {
2306 if (ssh->userpass_input_echo)
2307 c_write_str(ssh, "\b \b");
2308 ssh->userpass_input_bufpos--;
0405e71f 2309 }
2310 break;
2311 case 21:
2312 case 27:
51470298 2313 while (ssh->userpass_input_bufpos > 0) {
2314 if (ssh->userpass_input_echo)
2315 c_write_str(ssh, "\b \b");
2316 ssh->userpass_input_bufpos--;
0405e71f 2317 }
2318 break;
2319 case 3:
2320 case 4:
2321 return -1;
2322 break;
2323 default:
4692a14a 2324 /*
2325 * This simplistic check for printability is disabled
2326 * when we're doing password input, because some people
2327 * have control characters in their passwords.o
2328 */
2329 if ((!ssh->userpass_input_echo ||
2330 (c >= ' ' && c <= '~') ||
0405e71f 2331 ((unsigned char) c >= 160))
51470298 2332 && ssh->userpass_input_bufpos < ssh->userpass_input_buflen-1) {
2333 ssh->userpass_input_buffer[ssh->userpass_input_bufpos++] = c;
2334 if (ssh->userpass_input_echo)
2335 c_write(ssh, &c, 1);
0405e71f 2336 }
2337 break;
2338 }
2339 }
2340 return 0;
2341}
2342
f11d78f2 2343static void ssh_agent_callback(void *sshv, void *reply, int replylen)
839f10db 2344{
2345 Ssh ssh = (Ssh) sshv;
2346
2347 ssh->agent_response = reply;
2348 ssh->agent_response_len = replylen;
2349
2350 if (ssh->version == 1)
2351 do_ssh1_login(ssh, NULL, -1, 0);
2352 else
2353 do_ssh2_authconn(ssh, NULL, -1, 0);
2354}
2355
f11d78f2 2356static void ssh_agentf_callback(void *cv, void *reply, int replylen)
839f10db 2357{
2358 struct ssh_channel *c = (struct ssh_channel *)cv;
2359 Ssh ssh = c->ssh;
2360 void *sentreply = reply;
2361
2362 if (!sentreply) {
2363 /* Fake SSH_AGENT_FAILURE. */
2364 sentreply = "\0\0\0\1\5";
2365 replylen = 5;
2366 }
2367 if (ssh->version == 2) {
2368 ssh2_add_channel_data(c, sentreply, replylen);
2369 ssh2_try_send(c);
2370 } else {
2371 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
2372 PKT_INT, c->remoteid,
2373 PKT_INT, replylen,
2374 PKT_DATA, sentreply, replylen,
2375 PKT_END);
2376 }
2377 if (reply)
2378 sfree(reply);
2379}
2380
0405e71f 2381/*
fb09bf1c 2382 * Handle the key exchange and user authentication phases.
2383 */
51470298 2384static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
fb09bf1c 2385{
0016d70b 2386 int i, j, ret;
2387 unsigned char cookie[8], *ptr;
374330e2 2388 struct RSAKey servkey, hostkey;
2389 struct MD5Context md5c;
51470298 2390 struct do_ssh1_login_state {
2391 int len;
2392 unsigned char *rsabuf, *keystr1, *keystr2;
2393 unsigned long supported_ciphers_mask, supported_auths_mask;
2394 int tried_publickey, tried_agent;
2395 int tis_auth_refused, ccard_auth_refused;
2396 unsigned char session_id[16];
2397 int cipher_type;
2398 char username[100];
2399 void *publickey_blob;
2400 int publickey_bloblen;
2401 char password[100];
2402 char prompt[200];
2403 int pos;
2404 char c;
2405 int pwpkt_type;
2406 unsigned char request[5], *response, *p;
2407 int responselen;
2408 int keyi, nkeys;
2409 int authed;
2410 struct RSAKey key;
2411 Bignum challenge;
2412 char *commentp;
2413 int commentlen;
2414 };
2415 crState(do_ssh1_login_state);
2416
2417 crBegin(ssh->do_ssh1_login_crstate);
374330e2 2418
32874aea 2419 if (!ispkt)
2420 crWaitUntil(ispkt);
374330e2 2421
51470298 2422 if (ssh->pktin.type != SSH1_SMSG_PUBLIC_KEY) {
6b5cf8b4 2423 bombout(("Public key packet not received"));
7ffdbc1a 2424 crStop(0);
8d5de777 2425 }
374330e2 2426
c5e9c988 2427 logevent("Received public keys");
374330e2 2428
0016d70b 2429 ptr = ssh_pkt_getdata(ssh, 8);
2430 if (!ptr) {
2431 bombout(("SSH1 public key packet stopped before random cookie"));
2432 crStop(0);
2433 }
2434 memcpy(cookie, ptr, 8);
374330e2 2435
0016d70b 2436 if (!ssh1_pkt_getrsakey(ssh, &servkey, &s->keystr1) ||
2437 !ssh1_pkt_getrsakey(ssh, &hostkey, &s->keystr2)) {
2438 bombout(("SSH1 public key packet stopped before public keys"));
2439 crStop(0);
2440 }
374330e2 2441
c5e9c988 2442 /*
1c2a93c4 2443 * Log the host key fingerprint.
c5e9c988 2444 */
c5e9c988 2445 {
2446 char logmsg[80];
1c2a93c4 2447 logevent("Host key fingerprint is:");
c5e9c988 2448 strcpy(logmsg, " ");
32874aea 2449 hostkey.comment = NULL;
2450 rsa_fingerprint(logmsg + strlen(logmsg),
2451 sizeof(logmsg) - strlen(logmsg), &hostkey);
c5e9c988 2452 logevent(logmsg);
2453 }
2454
0016d70b 2455 ssh->v1_remote_protoflags = ssh_pkt_getuint32(ssh);
2456 s->supported_ciphers_mask = ssh_pkt_getuint32(ssh);
2457 s->supported_auths_mask = ssh_pkt_getuint32(ssh);
bea1ef5f 2458
51470298 2459 ssh->v1_local_protoflags =
2460 ssh->v1_remote_protoflags & SSH1_PROTOFLAGS_SUPPORTED;
2461 ssh->v1_local_protoflags |= SSH1_PROTOFLAG_SCREEN_NUMBER;
b96dc54c 2462
c5e9c988 2463 MD5Init(&md5c);
51470298 2464 MD5Update(&md5c, s->keystr2, hostkey.bytes);
2465 MD5Update(&md5c, s->keystr1, servkey.bytes);
0016d70b 2466 MD5Update(&md5c, cookie, 8);
51470298 2467 MD5Final(s->session_id, &md5c);
374330e2 2468
32874aea 2469 for (i = 0; i < 32; i++)
51470298 2470 ssh->session_key[i] = random_byte();
374330e2 2471
0016d70b 2472 /*
2473 * Verify that the `bits' and `bytes' parameters match.
2474 */
2475 if (hostkey.bits > hostkey.bytes * 8 ||
2476 servkey.bits > servkey.bytes * 8) {
2477 bombout(("SSH1 public keys were badly formatted"));
2478 crStop(0);
2479 }
2480
51470298 2481 s->len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
374330e2 2482
3d88e64d 2483 s->rsabuf = snewn(s->len, unsigned char);
51470298 2484 if (!s->rsabuf)
374330e2 2485 fatalbox("Out of memory");
2486
89ee5268 2487 /*
2488 * Verify the host key.
2489 */
2490 {
32874aea 2491 /*
2492 * First format the key into a string.
2493 */
2494 int len = rsastr_len(&hostkey);
2495 char fingerprint[100];
3d88e64d 2496 char *keystr = snewn(len, char);
32874aea 2497 if (!keystr)
2498 fatalbox("Out of memory");
2499 rsastr_fmt(keystr, &hostkey);
2500 rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
a8327734 2501 verify_ssh_host_key(ssh->frontend,
2502 ssh->savedhost, ssh->savedport, "rsa", keystr,
32874aea 2503 fingerprint);
2504 sfree(keystr);
2505 }
2506
2507 for (i = 0; i < 32; i++) {
51470298 2508 s->rsabuf[i] = ssh->session_key[i];
374330e2 2509 if (i < 16)
51470298 2510 s->rsabuf[i] ^= s->session_id[i];
374330e2 2511 }
2512
2513 if (hostkey.bytes > servkey.bytes) {
0016d70b 2514 ret = rsaencrypt(s->rsabuf, 32, &servkey);
2515 if (ret)
2516 ret = rsaencrypt(s->rsabuf, servkey.bytes, &hostkey);
374330e2 2517 } else {
0016d70b 2518 ret = rsaencrypt(s->rsabuf, 32, &hostkey);
2519 if (ret)
2520 ret = rsaencrypt(s->rsabuf, hostkey.bytes, &servkey);
2521 }
2522 if (!ret) {
2523 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2524 crStop(0);
374330e2 2525 }
2526
c5e9c988 2527 logevent("Encrypted session key");
2528
ca20bfcf 2529 {
2530 int cipher_chosen = 0, warn = 0;
2531 char *cipher_string = NULL;
51470298 2532 int i;
ca20bfcf 2533 for (i = 0; !cipher_chosen && i < CIPHER_MAX; i++) {
86916870 2534 int next_cipher = ssh->cfg.ssh_cipherlist[i];
ca20bfcf 2535 if (next_cipher == CIPHER_WARN) {
2536 /* If/when we choose a cipher, warn about it */
2537 warn = 1;
2538 } else if (next_cipher == CIPHER_AES) {
2539 /* XXX Probably don't need to mention this. */
2540 logevent("AES not supported in SSH1, skipping");
2541 } else {
2542 switch (next_cipher) {
51470298 2543 case CIPHER_3DES: s->cipher_type = SSH_CIPHER_3DES;
ca20bfcf 2544 cipher_string = "3DES"; break;
51470298 2545 case CIPHER_BLOWFISH: s->cipher_type = SSH_CIPHER_BLOWFISH;
ca20bfcf 2546 cipher_string = "Blowfish"; break;
51470298 2547 case CIPHER_DES: s->cipher_type = SSH_CIPHER_DES;
ca20bfcf 2548 cipher_string = "single-DES"; break;
2549 }
51470298 2550 if (s->supported_ciphers_mask & (1 << s->cipher_type))
ca20bfcf 2551 cipher_chosen = 1;
2552 }
2553 }
2554 if (!cipher_chosen) {
51470298 2555 if ((s->supported_ciphers_mask & (1 << SSH_CIPHER_3DES)) == 0)
6b5cf8b4 2556 bombout(("Server violates SSH 1 protocol by not "
ca20bfcf 2557 "supporting 3DES encryption"));
2558 else
2559 /* shouldn't happen */
6b5cf8b4 2560 bombout(("No supported ciphers found"));
7ffdbc1a 2561 crStop(0);
a99a05c0 2562 }
ca20bfcf 2563
2564 /* Warn about chosen cipher if necessary. */
2565 if (warn)
a8327734 2566 askcipher(ssh->frontend, cipher_string, 0);
bea1ef5f 2567 }
ca20bfcf 2568
51470298 2569 switch (s->cipher_type) {
32874aea 2570 case SSH_CIPHER_3DES:
2571 logevent("Using 3DES encryption");
2572 break;
2573 case SSH_CIPHER_DES:
2574 logevent("Using single-DES encryption");
2575 break;
2576 case SSH_CIPHER_BLOWFISH:
2577 logevent("Using Blowfish encryption");
2578 break;
c5e9c988 2579 }
bea1ef5f 2580
51470298 2581 send_packet(ssh, SSH1_CMSG_SESSION_KEY,
2582 PKT_CHAR, s->cipher_type,
32874aea 2583 PKT_DATA, cookie, 8,
51470298 2584 PKT_CHAR, (s->len * 8) >> 8, PKT_CHAR, (s->len * 8) & 0xFF,
2585 PKT_DATA, s->rsabuf, s->len,
2586 PKT_INT, ssh->v1_local_protoflags, PKT_END);
fb09bf1c 2587
c5e9c988 2588 logevent("Trying to enable encryption...");
374330e2 2589
51470298 2590 sfree(s->rsabuf);
374330e2 2591
51470298 2592 ssh->cipher = (s->cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
2593 s->cipher_type == SSH_CIPHER_DES ? &ssh_des :
2594 &ssh_3des);
371e569c 2595 ssh->v1_cipher_ctx = ssh->cipher->make_context();
2596 ssh->cipher->sesskey(ssh->v1_cipher_ctx, ssh->session_key);
57356d63 2597 logeventf(ssh, "Initialised %s encryption", ssh->cipher->text_name);
374330e2 2598
0183b242 2599 ssh->crcda_ctx = crcda_make_context();
2600 logevent("Installing CRC compensation attack detector");
2601
679539d7 2602 if (servkey.modulus) {
2603 sfree(servkey.modulus);
2604 servkey.modulus = NULL;
2605 }
2606 if (servkey.exponent) {
2607 sfree(servkey.exponent);
2608 servkey.exponent = NULL;
2609 }
2610 if (hostkey.modulus) {
2611 sfree(hostkey.modulus);
2612 hostkey.modulus = NULL;
2613 }
2614 if (hostkey.exponent) {
2615 sfree(hostkey.exponent);
2616 hostkey.exponent = NULL;
2617 }
fb09bf1c 2618 crWaitUntil(ispkt);
374330e2 2619
51470298 2620 if (ssh->pktin.type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 2621 bombout(("Encryption not successfully enabled"));
7ffdbc1a 2622 crStop(0);
8d5de777 2623 }
374330e2 2624
c5e9c988 2625 logevent("Successfully started encryption");
2626
374330e2 2627 fflush(stdout);
2628 {
86916870 2629 if ((flags & FLAG_INTERACTIVE) && !*ssh->cfg.username) {
c0a81592 2630 if (ssh_get_line && !ssh_getline_pw_only) {
32874aea 2631 if (!ssh_get_line("login as: ",
51470298 2632 s->username, sizeof(s->username), FALSE)) {
32874aea 2633 /*
2634 * get_line failed to get a username.
2635 * Terminate.
2636 */
2637 logevent("No username provided. Abandoning session.");
3bb2f322 2638 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 2639 crStop(1);
32874aea 2640 }
2641 } else {
51470298 2642 int ret; /* need not be kept over crReturn */
2643 c_write_str(ssh, "login as: ");
2644 ssh->send_ok = 1;
0405e71f 2645
51470298 2646 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
0405e71f 2647 do {
32874aea 2648 crWaitUntil(!ispkt);
51470298 2649 ret = process_userpass_input(ssh, in, inlen);
0405e71f 2650 } while (ret == 0);
2651 if (ret < 0)
2652 cleanup_exit(0);
51470298 2653 c_write_str(ssh, "\r\n");
32874aea 2654 }
2655 } else {
86916870 2656 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
51470298 2657 s->username[sizeof(s->username)-1] = '\0';
374330e2 2658 }
fb09bf1c 2659
51470298 2660 send_packet(ssh, SSH1_CMSG_USER, PKT_STR, s->username, PKT_END);
c5e9c988 2661 {
51470298 2662 char userlog[22 + sizeof(s->username)];
2663 sprintf(userlog, "Sent username \"%s\"", s->username);
c5e9c988 2664 logevent(userlog);
32874aea 2665 if (flags & FLAG_INTERACTIVE &&
2666 (!((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)))) {
3c8e959b 2667 strcat(userlog, "\r\n");
51470298 2668 c_write_str(ssh, userlog);
3c8e959b 2669 }
c5e9c988 2670 }
374330e2 2671 }
2672
fb09bf1c 2673 crWaitUntil(ispkt);
374330e2 2674
51470298 2675 if ((ssh->remote_bugs & BUG_CHOKES_ON_RSA)) {
0df73905 2676 /* We must not attempt PK auth. Pretend we've already tried it. */
51470298 2677 s->tried_publickey = s->tried_agent = 1;
0df73905 2678 } else {
51470298 2679 s->tried_publickey = s->tried_agent = 0;
0df73905 2680 }
51470298 2681 s->tis_auth_refused = s->ccard_auth_refused = 0;
86916870 2682 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
9a30e26b 2683 if (!filename_is_null(ssh->cfg.keyfile)) {
2684 if (!rsakey_pubblob(&ssh->cfg.keyfile,
222d54dc 2685 &s->publickey_blob, &s->publickey_bloblen, NULL))
51470298 2686 s->publickey_blob = NULL;
396778f1 2687 } else
51470298 2688 s->publickey_blob = NULL;
7cca0d81 2689
51470298 2690 while (ssh->pktin.type == SSH1_SMSG_FAILURE) {
2691 s->pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
614a20a0 2692
51470298 2693 if (agent_exists() && !s->tried_agent) {
32874aea 2694 /*
2695 * Attempt RSA authentication using Pageant.
2696 */
32874aea 2697 void *r;
2698
51470298 2699 s->authed = FALSE;
2700 s->tried_agent = 1;
32874aea 2701 logevent("Pageant is running. Requesting keys.");
2702
2703 /* Request the keys held by the agent. */
51470298 2704 PUT_32BIT(s->request, 1);
2705 s->request[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES;
839f10db 2706 if (!agent_query(s->request, 5, &r, &s->responselen,
2707 ssh_agent_callback, ssh)) {
2708 do {
2709 crReturn(0);
2710 if (ispkt) {
2711 bombout(("Unexpected data from server while waiting"
2712 " for agent response"));
2713 crStop(0);
2714 }
2715 } while (ispkt || inlen > 0);
2716 r = ssh->agent_response;
2717 s->responselen = ssh->agent_response_len;
2718 }
51470298 2719 s->response = (unsigned char *) r;
2720 if (s->response && s->responselen >= 5 &&
2721 s->response[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER) {
2722 s->p = s->response + 5;
2723 s->nkeys = GET_32BIT(s->p);
2724 s->p += 4;
32874aea 2725 {
2726 char buf[64];
51470298 2727 sprintf(buf, "Pageant has %d SSH1 keys", s->nkeys);
32874aea 2728 logevent(buf);
2729 }
51470298 2730 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
32874aea 2731 {
2732 char buf[64];
51470298 2733 sprintf(buf, "Trying Pageant key #%d", s->keyi);
32874aea 2734 logevent(buf);
2735 }
51470298 2736 if (s->publickey_blob &&
2737 !memcmp(s->p, s->publickey_blob,
2738 s->publickey_bloblen)) {
396778f1 2739 logevent("This key matches configured key file");
51470298 2740 s->tried_publickey = 1;
396778f1 2741 }
51470298 2742 s->p += 4;
0016d70b 2743 {
2744 int n, ok = FALSE;
2745 do { /* do while (0) to make breaking easy */
2746 n = ssh1_read_bignum
2747 (s->p, s->responselen-(s->p-s->response),
2748 &s->key.exponent);
2749 if (n < 0)
2750 break;
2751 s->p += n;
2752 n = ssh1_read_bignum
2753 (s->p, s->responselen-(s->p-s->response),
2754 &s->key.modulus);
2755 if (n < 0)
2756 break;
2757 s->p += n;
2758 if (s->responselen - (s->p-s->response) < 4)
2759 break;
2760 s->commentlen = GET_32BIT(s->p);
2761 s->p += 4;
2762 if (s->responselen - (s->p-s->response) <
2763 s->commentlen)
2764 break;
2765 s->commentp = (char *)s->p;
2766 s->p += s->commentlen;
2767 ok = TRUE;
2768 } while (0);
2769 if (!ok) {
2770 logevent("Pageant key list packet was truncated");
2771 break;
2772 }
2773 }
51470298 2774 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
2775 PKT_BIGNUM, s->key.modulus, PKT_END);
32874aea 2776 crWaitUntil(ispkt);
51470298 2777 if (ssh->pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
32874aea 2778 logevent("Key refused");
2779 continue;
2780 }
2781 logevent("Received RSA challenge");
0016d70b 2782 if ((s->challenge = ssh1_pkt_getmp(ssh)) == NULL) {
2783 bombout(("Server's RSA challenge was badly formatted"));
2784 crStop(0);
2785 }
2786
32874aea 2787 {
2788 char *agentreq, *q, *ret;
2d466ffd 2789 void *vret;
32874aea 2790 int len, retlen;
2791 len = 1 + 4; /* message type, bit count */
51470298 2792 len += ssh1_bignum_length(s->key.exponent);
2793 len += ssh1_bignum_length(s->key.modulus);
2794 len += ssh1_bignum_length(s->challenge);
32874aea 2795 len += 16; /* session id */
2796 len += 4; /* response format */
3d88e64d 2797 agentreq = snewn(4 + len, char);
32874aea 2798 PUT_32BIT(agentreq, len);
2799 q = agentreq + 4;
2800 *q++ = SSH1_AGENTC_RSA_CHALLENGE;
51470298 2801 PUT_32BIT(q, bignum_bitcount(s->key.modulus));
32874aea 2802 q += 4;
51470298 2803 q += ssh1_write_bignum(q, s->key.exponent);
2804 q += ssh1_write_bignum(q, s->key.modulus);
2805 q += ssh1_write_bignum(q, s->challenge);
2806 memcpy(q, s->session_id, 16);
32874aea 2807 q += 16;
2808 PUT_32BIT(q, 1); /* response format */
839f10db 2809 if (!agent_query(agentreq, len + 4, &vret, &retlen,
2810 ssh_agent_callback, ssh)) {
2811 sfree(agentreq);
2812 do {
2813 crReturn(0);
2814 if (ispkt) {
2815 bombout(("Unexpected data from server"
2816 " while waiting for agent"
2817 " response"));
2818 crStop(0);
2819 }
2820 } while (ispkt || inlen > 0);
2821 vret = ssh->agent_response;
2822 retlen = ssh->agent_response_len;
2823 } else
2824 sfree(agentreq);
2d466ffd 2825 ret = vret;
32874aea 2826 if (ret) {
2827 if (ret[4] == SSH1_AGENT_RSA_RESPONSE) {
2828 logevent("Sending Pageant's response");
51470298 2829 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
32874aea 2830 PKT_DATA, ret + 5, 16,
2831 PKT_END);
2832 sfree(ret);
2833 crWaitUntil(ispkt);
51470298 2834 if (ssh->pktin.type == SSH1_SMSG_SUCCESS) {
32874aea 2835 logevent
2836 ("Pageant's response accepted");
2837 if (flags & FLAG_VERBOSE) {
51470298 2838 c_write_str(ssh, "Authenticated using"
2839 " RSA key \"");
2840 c_write(ssh, s->commentp,
2841 s->commentlen);
2842 c_write_str(ssh, "\" from agent\r\n");
32874aea 2843 }
51470298 2844 s->authed = TRUE;
32874aea 2845 } else
2846 logevent
2847 ("Pageant's response not accepted");
2848 } else {
2849 logevent
2850 ("Pageant failed to answer challenge");
2851 sfree(ret);
2852 }
2853 } else {
2854 logevent("No reply received from Pageant");
2855 }
2856 }
51470298 2857 freebn(s->key.exponent);
2858 freebn(s->key.modulus);
2859 freebn(s->challenge);
2860 if (s->authed)
32874aea 2861 break;
2862 }
29b1d0b3 2863 sfree(s->response);
32874aea 2864 }
51470298 2865 if (s->authed)
32874aea 2866 break;
2867 }
9a30e26b 2868 if (!filename_is_null(ssh->cfg.keyfile) && !s->tried_publickey)
51470298 2869 s->pwpkt_type = SSH1_CMSG_AUTH_RSA;
32874aea 2870
86916870 2871 if (ssh->cfg.try_tis_auth &&
51470298 2872 (s->supported_auths_mask & (1 << SSH1_AUTH_TIS)) &&
2873 !s->tis_auth_refused) {
2874 s->pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
32874aea 2875 logevent("Requested TIS authentication");
51470298 2876 send_packet(ssh, SSH1_CMSG_AUTH_TIS, PKT_END);
32874aea 2877 crWaitUntil(ispkt);
51470298 2878 if (ssh->pktin.type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
32874aea 2879 logevent("TIS authentication declined");
2880 if (flags & FLAG_INTERACTIVE)
51470298 2881 c_write_str(ssh, "TIS authentication refused.\r\n");
2882 s->tis_auth_refused = 1;
614a20a0 2883 continue;
32874aea 2884 } else {
0016d70b 2885 char *challenge;
2886 int challengelen;
2887
2888 ssh_pkt_getstring(ssh, &challenge, &challengelen);
2889 if (!challenge) {
2890 bombout(("TIS challenge packet was badly formed"));
2891 crStop(0);
2892 }
32874aea 2893 logevent("Received TIS challenge");
51470298 2894 if (challengelen > sizeof(s->prompt) - 1)
2895 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
0016d70b 2896 memcpy(s->prompt, challenge, challengelen);
614a20a0 2897 /* Prompt heuristic comes from OpenSSH */
51470298 2898 strncpy(s->prompt + challengelen,
2899 memchr(s->prompt, '\n', challengelen) ?
614a20a0 2900 "": "\r\nResponse: ",
51470298 2901 (sizeof s->prompt) - challengelen);
2902 s->prompt[(sizeof s->prompt) - 1] = '\0';
32874aea 2903 }
2904 }
86916870 2905 if (ssh->cfg.try_tis_auth &&
51470298 2906 (s->supported_auths_mask & (1 << SSH1_AUTH_CCARD)) &&
2907 !s->ccard_auth_refused) {
2908 s->pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
32874aea 2909 logevent("Requested CryptoCard authentication");
51470298 2910 send_packet(ssh, SSH1_CMSG_AUTH_CCARD, PKT_END);
32874aea 2911 crWaitUntil(ispkt);
51470298 2912 if (ssh->pktin.type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
32874aea 2913 logevent("CryptoCard authentication declined");
51470298 2914 c_write_str(ssh, "CryptoCard authentication refused.\r\n");
2915 s->ccard_auth_refused = 1;
614a20a0 2916 continue;
32874aea 2917 } else {
0016d70b 2918 char *challenge;
2919 int challengelen;
2920
2921 ssh_pkt_getstring(ssh, &challenge, &challengelen);
2922 if (!challenge) {
2923 bombout(("CryptoCard challenge packet was badly formed"));
2924 crStop(0);
2925 }
32874aea 2926 logevent("Received CryptoCard challenge");
51470298 2927 if (challengelen > sizeof(s->prompt) - 1)
2928 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
0016d70b 2929 memcpy(s->prompt, challenge, challengelen);
51470298 2930 strncpy(s->prompt + challengelen,
2931 memchr(s->prompt, '\n', challengelen) ?
614a20a0 2932 "" : "\r\nResponse: ",
51470298 2933 sizeof(s->prompt) - challengelen);
2934 s->prompt[sizeof(s->prompt) - 1] = '\0';
32874aea 2935 }
2936 }
51470298 2937 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
2938 sprintf(s->prompt, "%.90s@%.90s's password: ",
2939 s->username, ssh->savedhost);
32874aea 2940 }
51470298 2941 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
32874aea 2942 char *comment = NULL;
231ee168 2943 int type;
2944 char msgbuf[256];
32874aea 2945 if (flags & FLAG_VERBOSE)
51470298 2946 c_write_str(ssh, "Trying public key authentication.\r\n");
6c6d9ed9 2947 logeventf(ssh, "Trying public key \"%s\"",
2948 filename_to_str(&ssh->cfg.keyfile));
9a30e26b 2949 type = key_type(&ssh->cfg.keyfile);
231ee168 2950 if (type != SSH_KEYTYPE_SSH1) {
2951 sprintf(msgbuf, "Key is of wrong type (%s)",
2952 key_type_to_str(type));
2953 logevent(msgbuf);
51470298 2954 c_write_str(ssh, msgbuf);
2955 c_write_str(ssh, "\r\n");
2956 s->tried_publickey = 1;
231ee168 2957 continue;
2958 }
9a30e26b 2959 if (!rsakey_encrypted(&ssh->cfg.keyfile, &comment)) {
32874aea 2960 if (flags & FLAG_VERBOSE)
51470298 2961 c_write_str(ssh, "No passphrase required.\r\n");
32874aea 2962 goto tryauth;
2963 }
51470298 2964 sprintf(s->prompt, "Passphrase for key \"%.100s\": ", comment);
32874aea 2965 sfree(comment);
2966 }
a52f067e 2967
614a20a0 2968 /*
2969 * Show password prompt, having first obtained it via a TIS
2970 * or CryptoCard exchange if we're doing TIS or CryptoCard
2971 * authentication.
2972 */
fa17a66e 2973 if (ssh_get_line) {
51470298 2974 if (!ssh_get_line(s->prompt, s->password,
2975 sizeof(s->password), TRUE)) {
32874aea 2976 /*
2977 * get_line failed to get a password (for example
2978 * because one was supplied on the command line
2979 * which has already failed to work). Terminate.
2980 */
51470298 2981 send_packet(ssh, SSH1_MSG_DISCONNECT,
2bc6a386 2982 PKT_STR, "No more passwords available to try",
2983 PKT_END);
247308b5 2984 logevent("Unable to authenticate");
a8327734 2985 connection_fatal(ssh->frontend, "Unable to authenticate");
3bb2f322 2986 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 2987 crStop(1);
32874aea 2988 }
fb09bf1c 2989 } else {
614a20a0 2990 /* Prompt may have come from server. We've munged it a bit, so
2991 * we know it to be zero-terminated at least once. */
51470298 2992 int ret; /* need not be saved over crReturn */
2993 c_write_untrusted(ssh, s->prompt, strlen(s->prompt));
2994 s->pos = 0;
0405e71f 2995
51470298 2996 setup_userpass_input(ssh, s->password, sizeof(s->password), 0);
0405e71f 2997 do {
32874aea 2998 crWaitUntil(!ispkt);
51470298 2999 ret = process_userpass_input(ssh, in, inlen);
0405e71f 3000 } while (ret == 0);
3001 if (ret < 0)
3002 cleanup_exit(0);
51470298 3003 c_write_str(ssh, "\r\n");
32874aea 3004 }
3005
3006 tryauth:
51470298 3007 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
32874aea 3008 /*
3009 * Try public key authentication with the specified
3010 * key file.
3011 */
51470298 3012 s->tried_publickey = 1;
3013
3014 {
222d54dc 3015 const char *error = NULL;
3016 int ret = loadrsakey(&ssh->cfg.keyfile, &s->key, s->password,
3017 &error);
51470298 3018 if (ret == 0) {
3019 c_write_str(ssh, "Couldn't load private key from ");
9fab77dc 3020 c_write_str(ssh, filename_to_str(&ssh->cfg.keyfile));
222d54dc 3021 c_write_str(ssh, " (");
3022 c_write_str(ssh, error);
3023 c_write_str(ssh, ").\r\n");
51470298 3024 continue; /* go and try password */
3025 }
3026 if (ret == -1) {
3027 c_write_str(ssh, "Wrong passphrase.\r\n");
3028 s->tried_publickey = 0;
3029 continue; /* try again */
3030 }
32874aea 3031 }
3032
3033 /*
3034 * Send a public key attempt.
3035 */
51470298 3036 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
3037 PKT_BIGNUM, s->key.modulus, PKT_END);
32874aea 3038
3039 crWaitUntil(ispkt);
51470298 3040 if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
3041 c_write_str(ssh, "Server refused our public key.\r\n");
32874aea 3042 continue; /* go and try password */
3043 }
51470298 3044 if (ssh->pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
6b5cf8b4 3045 bombout(("Bizarre response to offer of public key"));
7ffdbc1a 3046 crStop(0);
32874aea 3047 }
32874aea 3048
51470298 3049 {
3050 int i;
3051 unsigned char buffer[32];
3052 Bignum challenge, response;
3053
0016d70b 3054 if ((challenge = ssh1_pkt_getmp(ssh)) == NULL) {
3055 bombout(("Server's RSA challenge was badly formatted"));
3056 crStop(0);
3057 }
51470298 3058 response = rsadecrypt(challenge, &s->key);
3059 freebn(s->key.private_exponent);/* burn the evidence */
32874aea 3060
51470298 3061 for (i = 0; i < 32; i++) {
3062 buffer[i] = bignum_byte(response, 31 - i);
3063 }
3064
3065 MD5Init(&md5c);
3066 MD5Update(&md5c, buffer, 32);
3067 MD5Update(&md5c, s->session_id, 16);
3068 MD5Final(buffer, &md5c);
32874aea 3069
51470298 3070 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
3071 PKT_DATA, buffer, 16, PKT_END);
3072
3073 freebn(challenge);
3074 freebn(response);
3075 }
32874aea 3076
3077 crWaitUntil(ispkt);
51470298 3078 if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
32874aea 3079 if (flags & FLAG_VERBOSE)
51470298 3080 c_write_str(ssh, "Failed to authenticate with"
3081 " our public key.\r\n");
32874aea 3082 continue; /* go and try password */
51470298 3083 } else if (ssh->pktin.type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 3084 bombout(("Bizarre response to RSA authentication response"));
7ffdbc1a 3085 crStop(0);
32874aea 3086 }
3087
3088 break; /* we're through! */
3089 } else {
51470298 3090 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
32874aea 3091 /*
3092 * Defence against traffic analysis: we send a
3093 * whole bunch of packets containing strings of
3094 * different lengths. One of these strings is the
3095 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3096 * The others are all random data in
3097 * SSH1_MSG_IGNORE packets. This way a passive
3098 * listener can't tell which is the password, and
3099 * hence can't deduce the password length.
3100 *
3101 * Anybody with a password length greater than 16
3102 * bytes is going to have enough entropy in their
3103 * password that a listener won't find it _that_
3104 * much help to know how long it is. So what we'll
3105 * do is:
3106 *
3107 * - if password length < 16, we send 15 packets
3108 * containing string lengths 1 through 15
3109 *
3110 * - otherwise, we let N be the nearest multiple
3111 * of 8 below the password length, and send 8
3112 * packets containing string lengths N through
3113 * N+7. This won't obscure the order of
3114 * magnitude of the password length, but it will
3115 * introduce a bit of extra uncertainty.
3116 *
3117 * A few servers (the old 1.2.18 through 1.2.22)
3118 * can't deal with SSH1_MSG_IGNORE. For these
3119 * servers, we need an alternative defence. We make
3120 * use of the fact that the password is interpreted
3121 * as a C string: so we can append a NUL, then some
3122 * random data.
bd358db1 3123 *
3124 * One server (a Cisco one) can deal with neither
3125 * SSH1_MSG_IGNORE _nor_ a padded password string.
3126 * For this server we are left with no defences
3127 * against password length sniffing.
32874aea 3128 */
51470298 3129 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE)) {
b17c8428 3130 /*
3131 * The server can deal with SSH1_MSG_IGNORE, so
3132 * we can use the primary defence.
3133 */
32874aea 3134 int bottom, top, pwlen, i;
3135 char *randomstr;
3136
51470298 3137 pwlen = strlen(s->password);
32874aea 3138 if (pwlen < 16) {
3139 bottom = 0; /* zero length passwords are OK! :-) */
3140 top = 15;
3141 } else {
3142 bottom = pwlen & ~7;
3143 top = bottom + 7;
3144 }
3145
3146 assert(pwlen >= bottom && pwlen <= top);
3147
3d88e64d 3148 randomstr = snewn(top + 1, char);
32874aea 3149
3150 for (i = bottom; i <= top; i++) {
3151 if (i == pwlen)
51470298 3152 defer_packet(ssh, s->pwpkt_type,
3153 PKT_STR, s->password, PKT_END);
32874aea 3154 else {
3155 for (j = 0; j < i; j++) {
3156 do {
3157 randomstr[j] = random_byte();
3158 } while (randomstr[j] == '\0');
3159 }
3160 randomstr[i] = '\0';
51470298 3161 defer_packet(ssh, SSH1_MSG_IGNORE,
32874aea 3162 PKT_STR, randomstr, PKT_END);
3163 }
3164 }
bd358db1 3165 logevent("Sending password with camouflage packets");
51470298 3166 ssh_pkt_defersend(ssh);
679539d7 3167 sfree(randomstr);
bd358db1 3168 }
51470298 3169 else if (!(ssh->remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
b17c8428 3170 /*
3171 * The server can't deal with SSH1_MSG_IGNORE
3172 * but can deal with padded passwords, so we
3173 * can use the secondary defence.
3174 */
bd358db1 3175 char string[64];
51470298 3176 char *ss;
bd358db1 3177 int len;
3178
51470298 3179 len = strlen(s->password);
bd358db1 3180 if (len < sizeof(string)) {
51470298 3181 ss = string;
3182 strcpy(string, s->password);
bd358db1 3183 len++; /* cover the zero byte */
3184 while (len < sizeof(string)) {
3185 string[len++] = (char) random_byte();
3186 }
3187 } else {
51470298 3188 ss = s->password;
bd358db1 3189 }
3190 logevent("Sending length-padded password");
51470298 3191 send_packet(ssh, s->pwpkt_type, PKT_INT, len,
3192 PKT_DATA, ss, len, PKT_END);
bd358db1 3193 } else {
3194 /*
3195 * The server has _both_
3196 * BUG_CHOKES_ON_SSH1_IGNORE and
3197 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3198 * therefore nothing we can do.
3199 */
3200 int len;
51470298 3201 len = strlen(s->password);
bd358db1 3202 logevent("Sending unpadded password");
51470298 3203 send_packet(ssh, s->pwpkt_type, PKT_INT, len,
3204 PKT_DATA, s->password, len, PKT_END);
32874aea 3205 }
3206 } else {
51470298 3207 send_packet(ssh, s->pwpkt_type, PKT_STR, s->password, PKT_END);
32874aea 3208 }
3209 }
c5e9c988 3210 logevent("Sent password");
51470298 3211 memset(s->password, 0, strlen(s->password));
fb09bf1c 3212 crWaitUntil(ispkt);
51470298 3213 if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
32874aea 3214 if (flags & FLAG_VERBOSE)
51470298 3215 c_write_str(ssh, "Access denied\r\n");
c5e9c988 3216 logevent("Authentication refused");
51470298 3217 } else if (ssh->pktin.type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 3218 bombout(("Strange packet received, type %d", ssh->pktin.type));
7ffdbc1a 3219 crStop(0);
374330e2 3220 }
3221 }
3222
c5e9c988 3223 logevent("Authentication successful");
3224
fb09bf1c 3225 crFinish(1);
3226}
3227
32874aea 3228void sshfwd_close(struct ssh_channel *c)
3229{
51470298 3230 Ssh ssh = c->ssh;
3231
36f94d1f 3232 if (ssh->state != SSH_STATE_SESSION) {
3233 assert(ssh->state == SSH_STATE_CLOSED);
3234 return;
3235 }
3236
80e48603 3237 if (c && !c->closes) {
4ed34d25 3238 /*
3239 * If the channel's remoteid is -1, we have sent
3240 * CHANNEL_OPEN for this channel, but it hasn't even been
3241 * acknowledged by the server. So we must set a close flag
3242 * on it now, and then when the server acks the channel
3243 * open, we can close it then.
3244 */
36cac739 3245 if (((int)c->remoteid) != -1) {
51470298 3246 if (ssh->version == 1) {
3247 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid,
4ed34d25 3248 PKT_END);
3249 } else {
51470298 3250 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_CLOSE);
3251 ssh2_pkt_adduint32(ssh, c->remoteid);
3252 ssh2_pkt_send(ssh);
4ed34d25 3253 }
32874aea 3254 }
0357890f 3255 c->closes = 1; /* sent MSG_CLOSE */
32874aea 3256 if (c->type == CHAN_X11) {
3257 c->u.x11.s = NULL;
d74d141c 3258 logevent("Forwarded X11 connection terminated");
4ed34d25 3259 } else if (c->type == CHAN_SOCKDATA ||
3260 c->type == CHAN_SOCKDATA_DORMANT) {
d74d141c 3261 c->u.pfd.s = NULL;
3262 logevent("Forwarded port closed");
32874aea 3263 }
3264 }
3265}
3266
5471d09a 3267int sshfwd_write(struct ssh_channel *c, char *buf, int len)
32874aea 3268{
51470298 3269 Ssh ssh = c->ssh;
3270
36f94d1f 3271 if (ssh->state != SSH_STATE_SESSION) {
3272 assert(ssh->state == SSH_STATE_CLOSED);
3273 return 0;
3274 }
3275
51470298 3276 if (ssh->version == 1) {
3277 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
32874aea 3278 PKT_INT, c->remoteid,
3279 PKT_INT, len, PKT_DATA, buf, len, PKT_END);
5471d09a 3280 /*
3281 * In SSH1 we can return 0 here - implying that forwarded
3282 * connections are never individually throttled - because
3283 * the only circumstance that can cause throttling will be
3284 * the whole SSH connection backing up, in which case
3285 * _everything_ will be throttled as a whole.
3286 */
3287 return 0;
783415f8 3288 } else {
32874aea 3289 ssh2_add_channel_data(c, buf, len);
5471d09a 3290 return ssh2_try_send(c);
3291 }
3292}
3293
3294void sshfwd_unthrottle(struct ssh_channel *c, int bufsize)
3295{
51470298 3296 Ssh ssh = c->ssh;
3297
36f94d1f 3298 if (ssh->state != SSH_STATE_SESSION) {
3299 assert(ssh->state == SSH_STATE_CLOSED);
3300 return;
3301 }
3302
51470298 3303 if (ssh->version == 1) {
5471d09a 3304 if (c->v.v1.throttling && bufsize < SSH1_BUFFER_LIMIT) {
3305 c->v.v1.throttling = 0;
51470298 3306 ssh1_throttle(ssh, -1);
5471d09a 3307 }
3308 } else {
3309 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
783415f8 3310 }
9c964e85 3311}
3312
51470298 3313static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
32874aea 3314{
51470298 3315 crBegin(ssh->ssh1_protocol_crstate);
fb09bf1c 3316
3317 random_init();
3318
51470298 3319 while (!do_ssh1_login(ssh, in, inlen, ispkt)) {
fb09bf1c 3320 crReturnV;
85ee8208 3321 }
51470298 3322 if (ssh->state == SSH_STATE_CLOSED)
32874aea 3323 crReturnV;
fb09bf1c 3324
86916870 3325 if (ssh->cfg.agentfwd && agent_exists()) {
32874aea 3326 logevent("Requesting agent forwarding");
51470298 3327 send_packet(ssh, SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
32874aea 3328 do {
3329 crReturnV;
3330 } while (!ispkt);
51470298 3331 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3332 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
6b5cf8b4 3333 bombout(("Protocol confusion"));
7ffdbc1a 3334 crStopV;
51470298 3335 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
32874aea 3336 logevent("Agent forwarding refused");
3337 } else {
3338 logevent("Agent forwarding enabled");
51470298 3339 ssh->agentfwd_enabled = TRUE;
db7d555c 3340 }
dacbd0e8 3341 }
3342
86916870 3343 if (ssh->cfg.x11_forward) {
32874aea 3344 char proto[20], data[64];
3345 logevent("Requesting X11 forwarding");
302121de 3346 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
86916870 3347 data, sizeof(data), ssh->cfg.x11_auth);
3348 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
51470298 3349 if (ssh->v1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) {
3350 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
32874aea 3351 PKT_STR, proto, PKT_STR, data,
86916870 3352 PKT_INT, x11_get_screen_number(ssh->cfg.x11_display),
421d6835 3353 PKT_END);
32874aea 3354 } else {
51470298 3355 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
32874aea 3356 PKT_STR, proto, PKT_STR, data, PKT_END);
3357 }
3358 do {
3359 crReturnV;
3360 } while (!ispkt);
51470298 3361 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3362 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
6b5cf8b4 3363 bombout(("Protocol confusion"));
7ffdbc1a 3364 crStopV;
51470298 3365 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
32874aea 3366 logevent("X11 forwarding refused");
3367 } else {
3368 logevent("X11 forwarding enabled");
51470298 3369 ssh->X11_fwd_enabled = TRUE;
9c964e85 3370 }
3371 }
3372
d74d141c 3373 {
9bf696b1 3374 char type;
d74d141c 3375 int n;
a4fc0d74 3376 int sport,dport,sserv,dserv;
6ee9b735 3377 char sports[256], dports[256], saddr[256], host[256];
d74d141c 3378
51470298 3379 ssh->rportfwds = newtree234(ssh_rportcmp_ssh1);
d74d141c 3380 /* Add port forwardings. */
86916870 3381 ssh->portfwd_strptr = ssh->cfg.portfwd;
51470298 3382 while (*ssh->portfwd_strptr) {
3383 type = *ssh->portfwd_strptr++;
6ee9b735 3384 saddr[0] = '\0';
d74d141c 3385 n = 0;
6ee9b735 3386 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != '\t') {
3387 if (*ssh->portfwd_strptr == ':') {
3388 /*
3389 * We've seen a colon in the middle of the
3390 * source port number. This means that
3391 * everything we've seen until now is the
3392 * source _address_, so we'll move it into
3393 * saddr and start sports from the beginning
3394 * again.
3395 */
3396 ssh->portfwd_strptr++;
3397 sports[n] = '\0';
3398 strcpy(saddr, sports);
3399 n = 0;
3400 }
3401 if (n < 255) sports[n++] = *ssh->portfwd_strptr++;
3402 }
d74d141c 3403 sports[n] = 0;
820ebe3b 3404 if (type != 'D') {
3405 if (*ssh->portfwd_strptr == '\t')
3406 ssh->portfwd_strptr++;
3407 n = 0;
3408 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != ':') {
3409 if (n < 255) host[n++] = *ssh->portfwd_strptr++;
3410 }
3411 host[n] = 0;
3412 if (*ssh->portfwd_strptr == ':')
3413 ssh->portfwd_strptr++;
3414 n = 0;
3415 while (*ssh->portfwd_strptr) {
3416 if (n < 255) dports[n++] = *ssh->portfwd_strptr++;
3417 }
3418 dports[n] = 0;
51470298 3419 ssh->portfwd_strptr++;
820ebe3b 3420 dport = atoi(dports);
3421 dserv = 0;
3422 if (dport == 0) {
3423 dserv = 1;
3424 dport = net_service_lookup(dports);
3425 if (!dport) {
3426 logeventf(ssh, "Service lookup failed for"
3427 " destination port \"%s\"", dports);
3428 }
a4fc0d74 3429 }
820ebe3b 3430 } else {
3431 while (*ssh->portfwd_strptr) ssh->portfwd_strptr++;
7ffdbc1a 3432 dport = dserv = -1;
7d5b0f4d 3433 ssh->portfwd_strptr++; /* eat the NUL and move to next one */
a4fc0d74 3434 }
d74d141c 3435 sport = atoi(sports);
a4fc0d74 3436 sserv = 0;
3437 if (sport == 0) {
3438 sserv = 1;
68a49acb 3439 sport = net_service_lookup(sports);
3440 if (!sport) {
57356d63 3441 logeventf(ssh, "Service lookup failed for source"
3442 " port \"%s\"", sports);
a4fc0d74 3443 }
3444 }
d74d141c 3445 if (sport && dport) {
3446 if (type == 'L') {
6ee9b735 3447 pfd_addforward(host, dport, *saddr ? saddr : NULL,
e8fa8f62 3448 sport, ssh, &ssh->cfg);
6ee9b735 3449 logeventf(ssh, "Local port %.*s%.*s%.*s%.*s%d%.*s"
3450 " forwarding to %s:%.*s%.*s%d%.*s",
3451 (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
3452 (int)(*saddr?1:0), ":",
57356d63 3453 (int)(sserv ? strlen(sports) : 0), sports,
3454 sserv, "(", sport, sserv, ")",
3455 host,
3456 (int)(dserv ? strlen(dports) : 0), dports,
3457 dserv, "(", dport, dserv, ")");
820ebe3b 3458 } else if (type == 'D') {
3459 pfd_addforward(NULL, -1, *saddr ? saddr : NULL,
3460 sport, ssh, &ssh->cfg);
3461 logeventf(ssh, "Local port %.*s%.*s%.*s%.*s%d%.*s"
3462 " doing SOCKS dynamic forwarding",
3463 (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
3464 (int)(*saddr?1:0), ":",
3465 (int)(sserv ? strlen(sports) : 0), sports,
3466 sserv, "(", sport, sserv, ")");
d74d141c 3467 } else {
3468 struct ssh_rportfwd *pf;
3d88e64d 3469 pf = snew(struct ssh_rportfwd);
bc240b21 3470 strcpy(pf->dhost, host);
3471 pf->dport = dport;
0cd494d7 3472 if (*saddr) {
6ee9b735 3473 logeventf(ssh,
3474 "SSH1 cannot handle source address spec \"%s:%d\"; ignoring",
3475 saddr, sport);
3476 }
51470298 3477 if (add234(ssh->rportfwds, pf) != pf) {
57356d63 3478 logeventf(ssh,
3479 "Duplicate remote port forwarding to %s:%d",
3480 host, dport);
bc240b21 3481 sfree(pf);
d74d141c 3482 } else {
57356d63 3483 logeventf(ssh, "Requesting remote port %.*s%.*s%d%.*s"
3484 " forward to %s:%.*s%.*s%d%.*s",
3485 (int)(sserv ? strlen(sports) : 0), sports,
3486 sserv, "(", sport, sserv, ")",
3487 host,
3488 (int)(dserv ? strlen(dports) : 0), dports,
3489 dserv, "(", dport, dserv, ")");
51470298 3490 send_packet(ssh, SSH1_CMSG_PORT_FORWARD_REQUEST,
d74d141c 3491 PKT_INT, sport,
3492 PKT_STR, host,
3493 PKT_INT, dport,
3494 PKT_END);
9bf696b1 3495 do {
3496 crReturnV;
3497 } while (!ispkt);
51470298 3498 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3499 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
6b5cf8b4 3500 bombout(("Protocol confusion"));
7ffdbc1a 3501 crStopV;
51470298 3502 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
3503 c_write_str(ssh, "Server refused port"
3504 " forwarding\r\n");
9bf696b1 3505 }
3506 logevent("Remote port forwarding enabled");
d74d141c 3507 }
3508 }
3509 }
3510 }
3511 }
3512
86916870 3513 if (!ssh->cfg.nopty) {
a5dd8467 3514 /* Unpick the terminal-speed string. */
3515 /* XXX perhaps we should allow no speeds to be sent. */
db219738 3516 ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
3517 sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
a5dd8467 3518 /* Send the pty request. */
51470298 3519 send_packet(ssh, SSH1_CMSG_REQUEST_PTY,
86916870 3520 PKT_STR, ssh->cfg.termtype,
51470298 3521 PKT_INT, ssh->term_height,
3522 PKT_INT, ssh->term_width,
a5dd8467 3523 PKT_INT, 0, PKT_INT, 0, /* width,height in pixels */
db219738 3524 PKT_CHAR, 192, PKT_INT, ssh->ispeed, /* TTY_OP_ISPEED */
3525 PKT_CHAR, 193, PKT_INT, ssh->ospeed, /* TTY_OP_OSPEED */
a5dd8467 3526 PKT_CHAR, 0, PKT_END);
51470298 3527 ssh->state = SSH_STATE_INTERMED;
32874aea 3528 do {
3529 crReturnV;
3530 } while (!ispkt);
51470298 3531 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3532 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
6b5cf8b4 3533 bombout(("Protocol confusion"));
7ffdbc1a 3534 crStopV;
51470298 3535 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
3536 c_write_str(ssh, "Server refused to allocate pty\r\n");
3537 ssh->editing = ssh->echoing = 1;
32874aea 3538 }
a5dd8467 3539 logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
db219738 3540 ssh->ospeed, ssh->ispeed);
0965bee0 3541 } else {
51470298 3542 ssh->editing = ssh->echoing = 1;
374330e2 3543 }
3544
86916870 3545 if (ssh->cfg.compression) {
51470298 3546 send_packet(ssh, SSH1_CMSG_REQUEST_COMPRESSION, PKT_INT, 6, PKT_END);
32874aea 3547 do {
3548 crReturnV;
3549 } while (!ispkt);
51470298 3550 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3551 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
6b5cf8b4 3552 bombout(("Protocol confusion"));
7ffdbc1a 3553 crStopV;
51470298 3554 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
3555 c_write_str(ssh, "Server refused to compress\r\n");
32874aea 3556 }
4ba9b64b 3557 logevent("Started compression");
51470298 3558 ssh->v1_compressing = TRUE;
5366aed8 3559 ssh->cs_comp_ctx = zlib_compress_init();
3560 logevent("Initialised zlib (RFC1950) compression");
3561 ssh->sc_comp_ctx = zlib_decompress_init();
3562 logevent("Initialised zlib (RFC1950) decompression");
4ba9b64b 3563 }
3564
fd5e5847 3565 /*
3566 * Start the shell or command.
3567 *
3568 * Special case: if the first-choice command is an SSH2
3569 * subsystem (hence not usable here) and the second choice
3570 * exists, we fall straight back to that.
3571 */
3572 {
86916870 3573 char *cmd = ssh->cfg.remote_cmd_ptr;
fd5e5847 3574
86916870 3575 if (ssh->cfg.ssh_subsys && ssh->cfg.remote_cmd_ptr2) {
3576 cmd = ssh->cfg.remote_cmd_ptr2;
51470298 3577 ssh->fallback_cmd = TRUE;
fd5e5847 3578 }
3579 if (*cmd)
51470298 3580 send_packet(ssh, SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END);
fd5e5847 3581 else
51470298 3582 send_packet(ssh, SSH1_CMSG_EXEC_SHELL, PKT_END);
fd5e5847 3583 logevent("Started session");
3584 }
374330e2 3585
51470298 3586 ssh->state = SSH_STATE_SESSION;
3587 if (ssh->size_needed)
3588 ssh_size(ssh, ssh->term_width, ssh->term_height);
3589 if (ssh->eof_needed)
3590 ssh_special(ssh, TS_EOF);
374330e2 3591
b9d7bcad 3592 if (ssh->ldisc)
3593 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
51470298 3594 ssh->send_ok = 1;
3595 ssh->channels = newtree234(ssh_channelcmp);
374330e2 3596 while (1) {
3597 crReturnV;
3598 if (ispkt) {
51470298 3599 if (ssh->pktin.type == SSH1_SMSG_STDOUT_DATA ||
3600 ssh->pktin.type == SSH1_SMSG_STDERR_DATA) {
0016d70b 3601 char *string;
3602 int stringlen, bufsize;
3603
3604 ssh_pkt_getstring(ssh, &string, &stringlen);
3605 if (string == NULL) {
3606 bombout(("Incoming terminal data packet was badly formed"));
3607 crStopV;
3608 }
3609
3610 bufsize =
51470298 3611 from_backend(ssh->frontend,
3612 ssh->pktin.type == SSH1_SMSG_STDERR_DATA,
0016d70b 3613 string, stringlen);
51470298 3614 if (!ssh->v1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
3615 ssh->v1_stdout_throttling = 1;
3616 ssh1_throttle(ssh, +1);
5471d09a 3617 }
51470298 3618 } else if (ssh->pktin.type == SSH1_MSG_DISCONNECT) {
3bb2f322 3619 ssh_closing((Plug)ssh, NULL, 0, 0);
c5e9c988 3620 logevent("Received disconnect request");
7ffdbc1a 3621 crStopV;
51470298 3622 } else if (ssh->pktin.type == SSH1_SMSG_X11_OPEN) {
32874aea 3623 /* Remote side is trying to open a channel to talk to our
3624 * X-Server. Give them back a local channel number. */
3625 struct ssh_channel *c;
0016d70b 3626 int remoteid = ssh_pkt_getuint32(ssh);
9c964e85 3627
3628 logevent("Received X11 connect request");
3629 /* Refuse if X11 forwarding is disabled. */
51470298 3630 if (!ssh->X11_fwd_enabled) {
3631 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
0016d70b 3632 PKT_INT, remoteid, PKT_END);
9c964e85 3633 logevent("Rejected X11 connect request");
3634 } else {
3d88e64d 3635 c = snew(struct ssh_channel);
51470298 3636 c->ssh = ssh;
9c964e85 3637
86916870 3638 if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
e8fa8f62 3639 ssh->x11auth, NULL, -1, &ssh->cfg) != NULL) {
0016d70b 3640 logevent("Opening X11 forward connection failed");
32874aea 3641 sfree(c);
51470298 3642 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
0016d70b 3643 PKT_INT, remoteid, PKT_END);
9c964e85 3644 } else {
32874aea 3645 logevent
0016d70b 3646 ("Opening X11 forward connection succeeded");
3647 c->remoteid = remoteid;
51470298 3648 c->localid = alloc_channel_id(ssh);
32874aea 3649 c->closes = 0;
5471d09a 3650 c->v.v1.throttling = 0;
32874aea 3651 c->type = CHAN_X11; /* identify channel type */
51470298 3652 add234(ssh->channels, c);
3653 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
32874aea 3654 PKT_INT, c->remoteid, PKT_INT,
3655 c->localid, PKT_END);
3656 logevent("Opened X11 forward channel");
9c964e85 3657 }
3658 }
51470298 3659 } else if (ssh->pktin.type == SSH1_SMSG_AGENT_OPEN) {
32874aea 3660 /* Remote side is trying to open a channel to talk to our
3661 * agent. Give them back a local channel number. */
3662 struct ssh_channel *c;
0016d70b 3663 int remoteid = ssh_pkt_getuint32(ssh);
db7d555c 3664
3665 /* Refuse if agent forwarding is disabled. */
51470298 3666 if (!ssh->agentfwd_enabled) {
3667 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
0016d70b 3668 PKT_INT, remoteid, PKT_END);
db7d555c 3669 } else {
3d88e64d 3670 c = snew(struct ssh_channel);
51470298 3671 c->ssh = ssh;
0016d70b 3672 c->remoteid = remoteid;
51470298 3673 c->localid = alloc_channel_id(ssh);
db7d555c 3674 c->closes = 0;
5471d09a 3675 c->v.v1.throttling = 0;
32874aea 3676 c->type = CHAN_AGENT; /* identify channel type */
db7d555c 3677 c->u.a.lensofar = 0;
51470298 3678 add234(ssh->channels, c);
3679 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
db7d555c 3680 PKT_INT, c->remoteid, PKT_INT, c->localid,
3681 PKT_END);
3682 }
51470298 3683 } else if (ssh->pktin.type == SSH1_MSG_PORT_OPEN) {
d74d141c 3684 /* Remote side is trying to open a channel to talk to a
3685 * forwarded port. Give them back a local channel number. */
3686 struct ssh_channel *c;
3687 struct ssh_rportfwd pf;
0016d70b 3688 int remoteid;
d74d141c 3689 int hostsize, port;
0016d70b 3690 char *host, buf[1024];
cbe2d68f 3691 const char *e;
3d88e64d 3692 c = snew(struct ssh_channel);
51470298 3693 c->ssh = ssh;
d74d141c 3694
0016d70b 3695 remoteid = ssh_pkt_getuint32(ssh);
3696 ssh_pkt_getstring(ssh, &host, &hostsize);
3697 port = ssh_pkt_getuint32(ssh);
d74d141c 3698
0016d70b 3699 if (hostsize >= lenof(pf.dhost))
3700 hostsize = lenof(pf.dhost)-1;
3701 memcpy(pf.dhost, host, hostsize);
3702 pf.dhost[hostsize] = '\0';
bc240b21 3703 pf.dport = port;
d74d141c 3704
51470298 3705 if (find234(ssh->rportfwds, &pf, NULL) == NULL) {
d74d141c 3706 sprintf(buf, "Rejected remote port open request for %s:%d",
0016d70b 3707 pf.dhost, port);
d74d141c 3708 logevent(buf);
51470298 3709 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
0016d70b 3710 PKT_INT, remoteid, PKT_END);
d74d141c 3711 } else {
3712 sprintf(buf, "Received remote port open request for %s:%d",
0016d70b 3713 pf.dhost, port);
d74d141c 3714 logevent(buf);
0016d70b 3715 e = pfd_newconnect(&c->u.pfd.s, pf.dhost, port,
3716 c, &ssh->cfg);
d74d141c 3717 if (e != NULL) {
3718 char buf[256];
3719 sprintf(buf, "Port open failed: %s", e);
3720 logevent(buf);
3721 sfree(c);
51470298 3722 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
0016d70b 3723 PKT_INT, remoteid, PKT_END);
d74d141c 3724 } else {
0016d70b 3725 c->remoteid = remoteid;
51470298 3726 c->localid = alloc_channel_id(ssh);
d74d141c 3727 c->closes = 0;
5471d09a 3728 c->v.v1.throttling = 0;
d74d141c 3729 c->type = CHAN_SOCKDATA; /* identify channel type */
51470298 3730 add234(ssh->channels, c);
3731 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
d74d141c 3732 PKT_INT, c->remoteid, PKT_INT,
3733 c->localid, PKT_END);
3734 logevent("Forwarded port opened successfully");
3735 }
3736 }
3737
51470298 3738 } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_OPEN_CONFIRMATION) {
0016d70b 3739 unsigned int remoteid = ssh_pkt_getuint32(ssh);
3740 unsigned int localid = ssh_pkt_getuint32(ssh);
bc240b21 3741 struct ssh_channel *c;
3742
51470298 3743 c = find234(ssh->channels, &remoteid, ssh_channelfind);
bc240b21 3744 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
3745 c->remoteid = localid;
3746 c->type = CHAN_SOCKDATA;
7781f316 3747 c->v.v1.throttling = 0;
bc240b21 3748 pfd_confirm(c->u.pfd.s);
3749 }
d74d141c 3750
4ed34d25 3751 if (c && c->closes) {
3752 /*
3753 * We have a pending close on this channel,
3754 * which we decided on before the server acked
3755 * the channel open. So now we know the
3756 * remoteid, we can close it again.
3757 */
51470298 3758 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE,
3759 PKT_INT, c->remoteid, PKT_END);
4ed34d25 3760 }
3761
51470298 3762 } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_OPEN_FAILURE) {
0016d70b 3763 unsigned int remoteid = ssh_pkt_getuint32(ssh);
724cface 3764 struct ssh_channel *c;
3765
51470298 3766 c = find234(ssh->channels, &remoteid, ssh_channelfind);
724cface 3767 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
3768 logevent("Forwarded connection refused by server");
3769 pfd_close(c->u.pfd.s);
51470298 3770 del234(ssh->channels, c);
724cface 3771 sfree(c);
3772 }
3773
51470298 3774 } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE ||
3775 ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) {
32874aea 3776 /* Remote side closes a channel. */
0016d70b 3777 unsigned i = ssh_pkt_getuint32(ssh);
32874aea 3778 struct ssh_channel *c;
51470298 3779 c = find234(ssh->channels, &i, ssh_channelfind);
d0d844c1 3780 if (c && ((int)c->remoteid) != -1) {
32874aea 3781 int closetype;
3782 closetype =
51470298 3783 (ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
0357890f 3784
783415f8 3785 if ((c->closes == 0) && (c->type == CHAN_X11)) {
d74d141c 3786 logevent("Forwarded X11 connection terminated");
9c964e85 3787 assert(c->u.x11.s != NULL);
3788 x11_close(c->u.x11.s);
3789 c->u.x11.s = NULL;
3790 }
d74d141c 3791 if ((c->closes == 0) && (c->type == CHAN_SOCKDATA)) {
3792 logevent("Forwarded port closed");
3793 assert(c->u.pfd.s != NULL);
3794 pfd_close(c->u.pfd.s);
3795 c->u.pfd.s = NULL;
3796 }
0357890f 3797
3798 c->closes |= (closetype << 2); /* seen this message */
3799 if (!(c->closes & closetype)) {
51470298 3800 send_packet(ssh, ssh->pktin.type, PKT_INT, c->remoteid,
0357890f 3801 PKT_END);
3802 c->closes |= closetype; /* sent it too */
3803 }
3804
3805 if (c->closes == 15) {
51470298 3806 del234(ssh->channels, c);
32874aea 3807 sfree(c);
3808 }
d0d844c1 3809 } else {
6b5cf8b4 3810 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
51470298 3811 ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE ? "" :
d0d844c1 3812 "_CONFIRMATION", c ? "half-open" : "nonexistent",
3813 i));
7ffdbc1a 3814 crStopV;
32874aea 3815 }
51470298 3816 } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_DATA) {
32874aea 3817 /* Data sent down one of our channels. */
0016d70b 3818 int i = ssh_pkt_getuint32(ssh);
3819 char *p;
3820 int len;
32874aea 3821 struct ssh_channel *c;
0016d70b 3822
3823 ssh_pkt_getstring(ssh, &p, &len);
3824
51470298 3825 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 3826 if (c) {
7ffdbc1a 3827 int bufsize = 0;
32874aea 3828 switch (c->type) {
3829 case CHAN_X11:
0016d70b 3830 bufsize = x11_send(c->u.x11.s, p, len);
9c964e85 3831 break;
d74d141c 3832 case CHAN_SOCKDATA:
0016d70b 3833 bufsize = pfd_send(c->u.pfd.s, p, len);
bc240b21 3834 break;
32874aea 3835 case CHAN_AGENT:
3836 /* Data for an agent message. Buffer it. */
3837 while (len > 0) {
3838 if (c->u.a.lensofar < 4) {
3839 int l = min(4 - c->u.a.lensofar, len);
3840 memcpy(c->u.a.msglen + c->u.a.lensofar, p,
3841 l);
3842 p += l;
3843 len -= l;
3844 c->u.a.lensofar += l;
3845 }
3846 if (c->u.a.lensofar == 4) {
3847 c->u.a.totallen =
3848 4 + GET_32BIT(c->u.a.msglen);
3d88e64d 3849 c->u.a.message = snewn(c->u.a.totallen,
3850 unsigned char);
32874aea 3851 memcpy(c->u.a.message, c->u.a.msglen, 4);
3852 }
3853 if (c->u.a.lensofar >= 4 && len > 0) {
3854 int l =
3855 min(c->u.a.totallen - c->u.a.lensofar,
3856 len);
3857 memcpy(c->u.a.message + c->u.a.lensofar, p,
3858 l);
3859 p += l;
3860 len -= l;
3861 c->u.a.lensofar += l;
3862 }
3863 if (c->u.a.lensofar == c->u.a.totallen) {
839f10db 3864 void *reply;
32874aea 3865 int replylen;
839f10db 3866 if (agent_query(c->u.a.message,
3867 c->u.a.totallen,
3868 &reply, &replylen,
3869 ssh_agentf_callback, c))
3870 ssh_agentf_callback(c, reply, replylen);
32874aea 3871 sfree(c->u.a.message);
3872 c->u.a.lensofar = 0;
3873 }
3874 }
5471d09a 3875 bufsize = 0; /* agent channels never back up */
32874aea 3876 break;
3877 }
90347b95 3878 if (!c->v.v1.throttling && bufsize > SSH1_BUFFER_LIMIT) {
5471d09a 3879 c->v.v1.throttling = 1;
51470298 3880 ssh1_throttle(ssh, +1);
5471d09a 3881 }
32874aea 3882 }
51470298 3883 } else if (ssh->pktin.type == SSH1_SMSG_SUCCESS) {
972a41c8 3884 /* may be from EXEC_SHELL on some servers */
51470298 3885 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
972a41c8 3886 /* may be from EXEC_SHELL on some servers
374330e2 3887 * if no pty is available or in other odd cases. Ignore */
51470298 3888 } else if (ssh->pktin.type == SSH1_SMSG_EXIT_STATUS) {
d8d6c7e5 3889 char buf[100];
0016d70b 3890 ssh->exitcode = ssh_pkt_getuint32(ssh);
d8d6c7e5 3891 sprintf(buf, "Server sent command exit status %d",
51470298 3892 ssh->exitcode);
d8d6c7e5 3893 logevent(buf);
51470298 3894 send_packet(ssh, SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
4252c9cc 3895 /*
3896 * In case `helpful' firewalls or proxies tack
3897 * extra human-readable text on the end of the
3898 * session which we might mistake for another
3899 * encrypted packet, we close the session once
3900 * we've sent EXIT_CONFIRMATION.
3901 */
3bb2f322 3902 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 3903 crStopV;
374330e2 3904 } else {
6b5cf8b4 3905 bombout(("Strange packet received: type %d", ssh->pktin.type));
7ffdbc1a 3906 crStopV;
374330e2 3907 }
3908 } else {
8df7a775 3909 while (inlen > 0) {
3910 int len = min(inlen, 512);
51470298 3911 send_packet(ssh, SSH1_CMSG_STDIN_DATA,
8df7a775 3912 PKT_INT, len, PKT_DATA, in, len, PKT_END);
3913 in += len;
3914 inlen -= len;
3915 }
374330e2 3916 }
3917 }
3918
3919 crFinishV;
3920}
3921
3922/*
e5574168 3923 * Utility routine for decoding comma-separated strings in KEXINIT.
3924 */
32874aea 3925static int in_commasep_string(char *needle, char *haystack, int haylen)
3926{
57356d63 3927 int needlen;
3928 if (!needle || !haystack) /* protect against null pointers */
3929 return 0;
3930 needlen = strlen(needle);
e5574168 3931 while (1) {
32874aea 3932 /*
3933 * Is it at the start of the string?
3934 */
3935 if (haylen >= needlen && /* haystack is long enough */
3936 !memcmp(needle, haystack, needlen) && /* initial match */
3937 (haylen == needlen || haystack[needlen] == ',')
3938 /* either , or EOS follows */
3939 )
3940 return 1;
3941 /*
3942 * If not, search for the next comma and resume after that.
3943 * If no comma found, terminate.
3944 */
3945 while (haylen > 0 && *haystack != ',')
3946 haylen--, haystack++;
3947 if (haylen == 0)
3948 return 0;
3949 haylen--, haystack++; /* skip over comma itself */
e5574168 3950 }
3951}
3952
3953/*
d39f364a 3954 * SSH2 key creation method.
3955 */
d8baa528 3956static void ssh2_mkkey(Ssh ssh, Bignum K, unsigned char *H,
3957 unsigned char *sessid, char chr,
3958 unsigned char *keyspace)
32874aea 3959{
d39f364a 3960 SHA_State s;
3961 /* First 20 bytes. */
3962 SHA_Init(&s);
51470298 3963 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
088bde77 3964 sha_mpint(&s, K);
d39f364a 3965 SHA_Bytes(&s, H, 20);
3966 SHA_Bytes(&s, &chr, 1);
5e0d7cb8 3967 SHA_Bytes(&s, sessid, 20);
d39f364a 3968 SHA_Final(&s, keyspace);
3969 /* Next 20 bytes. */
3970 SHA_Init(&s);
51470298 3971 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
088bde77 3972 sha_mpint(&s, K);
d39f364a 3973 SHA_Bytes(&s, H, 20);
3974 SHA_Bytes(&s, keyspace, 20);
32874aea 3975 SHA_Final(&s, keyspace + 20);
d39f364a 3976}
3977
3978/*
7cca0d81 3979 * Handle the SSH2 transport layer.
e5574168 3980 */
51470298 3981static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
e5574168 3982{
51470298 3983 struct do_ssh2_transport_state {
3984 int nbits, pbits, warn;
3985 Bignum p, g, e, f, K;
3986 int kex_init_value, kex_reply_value;
3987 const struct ssh_mac **maclist;
3988 int nmacs;
3989 const struct ssh2_cipher *cscipher_tobe;
3990 const struct ssh2_cipher *sccipher_tobe;
3991 const struct ssh_mac *csmac_tobe;
3992 const struct ssh_mac *scmac_tobe;
3993 const struct ssh_compress *cscomp_tobe;
3994 const struct ssh_compress *sccomp_tobe;
3995 char *hostkeydata, *sigdata, *keystr, *fingerprint;
3996 int hostkeylen, siglen;
3997 void *hkey; /* actual host key */
3998 unsigned char exchange_hash[20];
3999 int n_preferred_ciphers;
4000 const struct ssh2_ciphers *preferred_ciphers[CIPHER_MAX];
4001 const struct ssh_compress *preferred_comp;
4002 int first_kex;
4003 };
4004 crState(do_ssh2_transport_state);
4005
4006 crBegin(ssh->do_ssh2_transport_crstate);
4007
4008 s->cscipher_tobe = s->sccipher_tobe = NULL;
4009 s->csmac_tobe = s->scmac_tobe = NULL;
4010 s->cscomp_tobe = s->sccomp_tobe = NULL;
4011
7cca0d81 4012 random_init();
51470298 4013 s->first_kex = 1;
e5574168 4014
51470298 4015 {
4016 int i;
4017 /*
4018 * Set up the preferred ciphers. (NULL => warn below here)
4019 */
4020 s->n_preferred_ciphers = 0;
4021 for (i = 0; i < CIPHER_MAX; i++) {
86916870 4022 switch (ssh->cfg.ssh_cipherlist[i]) {
51470298 4023 case CIPHER_BLOWFISH:
4024 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_blowfish;
4025 break;
4026 case CIPHER_DES:
86916870 4027 if (ssh->cfg.ssh2_des_cbc) {
51470298 4028 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_des;
4029 }
4030 break;
4031 case CIPHER_3DES:
4032 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_3des;
4033 break;
4034 case CIPHER_AES:
4035 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_aes;
4036 break;
4037 case CIPHER_WARN:
4038 /* Flag for later. Don't bother if it's the last in
4039 * the list. */
4040 if (i < CIPHER_MAX - 1) {
4041 s->preferred_ciphers[s->n_preferred_ciphers++] = NULL;
4042 }
4043 break;
ca20bfcf 4044 }
ca20bfcf 4045 }
5e8358ad 4046 }
ca20bfcf 4047
4048 /*
4049 * Set up preferred compression.
4050 */
86916870 4051 if (ssh->cfg.compression)
51470298 4052 s->preferred_comp = &ssh_zlib;
4ba9b64b 4053 else
51470298 4054 s->preferred_comp = &ssh_comp_none;
5e8358ad 4055
7591b9ff 4056 /*
4057 * Be prepared to work around the buggy MAC problem.
4058 */
51470298 4059 if (ssh->remote_bugs & BUG_SSH2_HMAC)
4060 s->maclist = buggymacs, s->nmacs = lenof(buggymacs);
7591b9ff 4061 else
51470298 4062 s->maclist = macs, s->nmacs = lenof(macs);
7591b9ff 4063
32874aea 4064 begin_key_exchange:
51470298 4065 {
4066 int i, j, cipherstr_started;
4067
4068 /*
4069 * Construct and send our key exchange packet.
4070 */
4071 ssh2_pkt_init(ssh, SSH2_MSG_KEXINIT);
4072 for (i = 0; i < 16; i++)
4073 ssh2_pkt_addbyte(ssh, (unsigned char) random_byte());
4074 /* List key exchange algorithms. */
4075 ssh2_pkt_addstring_start(ssh);
4076 for (i = 0; i < lenof(kex_algs); i++) {
4077 if (kex_algs[i] == &ssh_diffiehellman_gex &&
4078 (ssh->remote_bugs & BUG_SSH2_DH_GEX))
4079 continue;
4080 ssh2_pkt_addstring_str(ssh, kex_algs[i]->name);
4081 if (i < lenof(kex_algs) - 1)
4082 ssh2_pkt_addstring_str(ssh, ",");
32874aea 4083 }
51470298 4084 /* List server host key algorithms. */
4085 ssh2_pkt_addstring_start(ssh);
4086 for (i = 0; i < lenof(hostkey_algs); i++) {
4087 ssh2_pkt_addstring_str(ssh, hostkey_algs[i]->name);
4088 if (i < lenof(hostkey_algs) - 1)
4089 ssh2_pkt_addstring_str(ssh, ",");
32874aea 4090 }
51470298 4091 /* List client->server encryption algorithms. */
4092 ssh2_pkt_addstring_start(ssh);
4093 cipherstr_started = 0;
4094 for (i = 0; i < s->n_preferred_ciphers; i++) {
4095 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4096 if (!c) continue; /* warning flag */
4097 for (j = 0; j < c->nciphers; j++) {
4098 if (cipherstr_started)
4099 ssh2_pkt_addstring_str(ssh, ",");
4100 ssh2_pkt_addstring_str(ssh, c->list[j]->name);
4101 cipherstr_started = 1;
4102 }
4103 }
4104 /* List server->client encryption algorithms. */
4105 ssh2_pkt_addstring_start(ssh);
4106 cipherstr_started = 0;
4107 for (i = 0; i < s->n_preferred_ciphers; i++) {
4108 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4109 if (!c) continue; /* warning flag */
4110 for (j = 0; j < c->nciphers; j++) {
4111 if (cipherstr_started)
4112 ssh2_pkt_addstring_str(ssh, ",");
4113 ssh2_pkt_addstring_str(ssh, c->list[j]->name);
4114 cipherstr_started = 1;
4115 }
4116 }
4117 /* List client->server MAC algorithms. */
4118 ssh2_pkt_addstring_start(ssh);
4119 for (i = 0; i < s->nmacs; i++) {
4120 ssh2_pkt_addstring_str(ssh, s->maclist[i]->name);
4121 if (i < s->nmacs - 1)
4122 ssh2_pkt_addstring_str(ssh, ",");
4123 }
4124 /* List server->client MAC algorithms. */
4125 ssh2_pkt_addstring_start(ssh);
4126 for (i = 0; i < s->nmacs; i++) {
4127 ssh2_pkt_addstring_str(ssh, s->maclist[i]->name);
4128 if (i < s->nmacs - 1)
4129 ssh2_pkt_addstring_str(ssh, ",");
4130 }
4131 /* List client->server compression algorithms. */
4132 ssh2_pkt_addstring_start(ssh);
4133 for (i = 0; i < lenof(compressions) + 1; i++) {
4134 const struct ssh_compress *c =
4135 i == 0 ? s->preferred_comp : compressions[i - 1];
4136 ssh2_pkt_addstring_str(ssh, c->name);
4137 if (i < lenof(compressions))
4138 ssh2_pkt_addstring_str(ssh, ",");
4139 }
4140 /* List server->client compression algorithms. */
4141 ssh2_pkt_addstring_start(ssh);
4142 for (i = 0; i < lenof(compressions) + 1; i++) {
4143 const struct ssh_compress *c =
4144 i == 0 ? s->preferred_comp : compressions[i - 1];
4145 ssh2_pkt_addstring_str(ssh, c->name);
4146 if (i < lenof(compressions))
4147 ssh2_pkt_addstring_str(ssh, ",");
4148 }
4149 /* List client->server languages. Empty list. */
4150 ssh2_pkt_addstring_start(ssh);
4151 /* List server->client languages. Empty list. */
4152 ssh2_pkt_addstring_start(ssh);
4153 /* First KEX packet does _not_ follow, because we're not that brave. */
4154 ssh2_pkt_addbool(ssh, FALSE);
4155 /* Reserved. */
4156 ssh2_pkt_adduint32(ssh, 0);
e5574168 4157 }
0db56f73 4158
51470298 4159 ssh->exhash = ssh->exhashbase;
4160 sha_string(&ssh->exhash, ssh->pktout.data + 5, ssh->pktout.length - 5);
0db56f73 4161
51470298 4162 ssh2_pkt_send(ssh);
e5574168 4163
32874aea 4164 if (!ispkt)
4165 crWaitUntil(ispkt);
57356d63 4166 if (ssh->pktin.length > 5)
4167 sha_string(&ssh->exhash, ssh->pktin.data + 5, ssh->pktin.length - 5);
e5574168 4168
4169 /*
4170 * Now examine the other side's KEXINIT to see what we're up
4171 * to.
4172 */
51470298 4173 {
4174 char *str;
4175 int i, j, len;
4176
4177 if (ssh->pktin.type != SSH2_MSG_KEXINIT) {
6b5cf8b4 4178 bombout(("expected key exchange packet from server"));
7ffdbc1a 4179 crStop(0);
32874aea 4180 }
51470298 4181 ssh->kex = NULL;
4182 ssh->hostkey = NULL;
4183 s->cscipher_tobe = NULL;
4184 s->sccipher_tobe = NULL;
4185 s->csmac_tobe = NULL;
4186 s->scmac_tobe = NULL;
4187 s->cscomp_tobe = NULL;
4188 s->sccomp_tobe = NULL;
4189 ssh->pktin.savedpos += 16; /* skip garbage cookie */
0016d70b 4190 ssh_pkt_getstring(ssh, &str, &len); /* key exchange algorithms */
51470298 4191 for (i = 0; i < lenof(kex_algs); i++) {
4192 if (kex_algs[i] == &ssh_diffiehellman_gex &&
4193 (ssh->remote_bugs & BUG_SSH2_DH_GEX))
4194 continue;
4195 if (in_commasep_string(kex_algs[i]->name, str, len)) {
4196 ssh->kex = kex_algs[i];
4197 break;
4198 }
32874aea 4199 }
0016d70b 4200 ssh_pkt_getstring(ssh, &str, &len); /* host key algorithms */
51470298 4201 for (i = 0; i < lenof(hostkey_algs); i++) {
4202 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
4203 ssh->hostkey = hostkey_algs[i];
4204 break;
4205 }
4206 }
0016d70b 4207 ssh_pkt_getstring(ssh, &str, &len); /* client->server cipher */
51470298 4208 s->warn = 0;
4209 for (i = 0; i < s->n_preferred_ciphers; i++) {
4210 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4211 if (!c) {
4212 s->warn = 1;
4213 } else {
4214 for (j = 0; j < c->nciphers; j++) {
4215 if (in_commasep_string(c->list[j]->name, str, len)) {
4216 s->cscipher_tobe = c->list[j];
4217 break;
4218 }
ca20bfcf 4219 }
32874aea 4220 }
51470298 4221 if (s->cscipher_tobe) {
4222 if (s->warn)
a8327734 4223 askcipher(ssh->frontend, s->cscipher_tobe->name, 1);
51470298 4224 break;
4225 }
32874aea 4226 }
51470298 4227 if (!s->cscipher_tobe) {
6b5cf8b4 4228 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
57356d63 4229 str ? str : "(null)"));
7ffdbc1a 4230 crStop(0);
ca20bfcf 4231 }
0ef8f407 4232
0016d70b 4233 ssh_pkt_getstring(ssh, &str, &len); /* server->client cipher */
51470298 4234 s->warn = 0;
4235 for (i = 0; i < s->n_preferred_ciphers; i++) {
4236 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4237 if (!c) {
4238 s->warn = 1;
4239 } else {
4240 for (j = 0; j < c->nciphers; j++) {
4241 if (in_commasep_string(c->list[j]->name, str, len)) {
4242 s->sccipher_tobe = c->list[j];
4243 break;
4244 }
ca20bfcf 4245 }
32874aea 4246 }
51470298 4247 if (s->sccipher_tobe) {
4248 if (s->warn)
a8327734 4249 askcipher(ssh->frontend, s->sccipher_tobe->name, 2);
51470298 4250 break;
4251 }
32874aea 4252 }
51470298 4253 if (!s->sccipher_tobe) {
6b5cf8b4 4254 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
57356d63 4255 str ? str : "(null)"));
7ffdbc1a 4256 crStop(0);
ca20bfcf 4257 }
0ef8f407 4258
0016d70b 4259 ssh_pkt_getstring(ssh, &str, &len); /* client->server mac */
51470298 4260 for (i = 0; i < s->nmacs; i++) {
4261 if (in_commasep_string(s->maclist[i]->name, str, len)) {
4262 s->csmac_tobe = s->maclist[i];
4263 break;
4264 }
32874aea 4265 }
0016d70b 4266 ssh_pkt_getstring(ssh, &str, &len); /* server->client mac */
51470298 4267 for (i = 0; i < s->nmacs; i++) {
4268 if (in_commasep_string(s->maclist[i]->name, str, len)) {
4269 s->scmac_tobe = s->maclist[i];
4270 break;
4271 }
32874aea 4272 }
0016d70b 4273 ssh_pkt_getstring(ssh, &str, &len); /* client->server compression */
51470298 4274 for (i = 0; i < lenof(compressions) + 1; i++) {
4275 const struct ssh_compress *c =
4276 i == 0 ? s->preferred_comp : compressions[i - 1];
4277 if (in_commasep_string(c->name, str, len)) {
4278 s->cscomp_tobe = c;
4279 break;
4280 }
32874aea 4281 }
0016d70b 4282 ssh_pkt_getstring(ssh, &str, &len); /* server->client compression */
51470298 4283 for (i = 0; i < lenof(compressions) + 1; i++) {
4284 const struct ssh_compress *c =
4285 i == 0 ? s->preferred_comp : compressions[i - 1];
4286 if (in_commasep_string(c->name, str, len)) {
4287 s->sccomp_tobe = c;
4288 break;
4289 }
32874aea 4290 }
e5574168 4291 }
e5574168 4292
4293 /*
7bd5a860 4294 * Work out the number of bits of key we will need from the key
4295 * exchange. We start with the maximum key length of either
4296 * cipher...
4297 */
4298 {
32874aea 4299 int csbits, scbits;
7bd5a860 4300
51470298 4301 csbits = s->cscipher_tobe->keylen;
4302 scbits = s->sccipher_tobe->keylen;
4303 s->nbits = (csbits > scbits ? csbits : scbits);
7bd5a860 4304 }
4305 /* The keys only have 160-bit entropy, since they're based on
4306 * a SHA-1 hash. So cap the key size at 160 bits. */
51470298 4307 if (s->nbits > 160)
4308 s->nbits = 160;
7bd5a860 4309
4310 /*
a92dd380 4311 * If we're doing Diffie-Hellman group exchange, start by
4312 * requesting a group.
e5574168 4313 */
51470298 4314 if (ssh->kex == &ssh_diffiehellman_gex) {
32874aea 4315 logevent("Doing Diffie-Hellman group exchange");
51470298 4316 ssh->pkt_ctx |= SSH2_PKTCTX_DHGEX;
32874aea 4317 /*
4318 * Work out how big a DH group we will need to allow that
4319 * much data.
7bd5a860 4320 */
51470298 4321 s->pbits = 512 << ((s->nbits - 1) / 64);
4322 ssh2_pkt_init(ssh, SSH2_MSG_KEX_DH_GEX_REQUEST);
4323 ssh2_pkt_adduint32(ssh, s->pbits);
4324 ssh2_pkt_send(ssh);
32874aea 4325
4326 crWaitUntil(ispkt);
51470298 4327 if (ssh->pktin.type != SSH2_MSG_KEX_DH_GEX_GROUP) {
6b5cf8b4 4328 bombout(("expected key exchange group packet from server"));
7ffdbc1a 4329 crStop(0);
32874aea 4330 }
51470298 4331 s->p = ssh2_pkt_getmp(ssh);
4332 s->g = ssh2_pkt_getmp(ssh);
27cd7fc2 4333 ssh->kex_ctx = dh_setup_group(s->p, s->g);
51470298 4334 s->kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
4335 s->kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY;
a92dd380 4336 } else {
51470298 4337 ssh->pkt_ctx |= SSH2_PKTCTX_DHGROUP1;
27cd7fc2 4338 ssh->kex_ctx = dh_setup_group1();
51470298 4339 s->kex_init_value = SSH2_MSG_KEXDH_INIT;
4340 s->kex_reply_value = SSH2_MSG_KEXDH_REPLY;
8d5de777 4341 }
e5574168 4342
a92dd380 4343 logevent("Doing Diffie-Hellman key exchange");
e5574168 4344 /*
a92dd380 4345 * Now generate and send e for Diffie-Hellman.
e5574168 4346 */
27cd7fc2 4347 s->e = dh_create_e(ssh->kex_ctx, s->nbits * 2);
51470298 4348 ssh2_pkt_init(ssh, s->kex_init_value);
4349 ssh2_pkt_addmp(ssh, s->e);
4350 ssh2_pkt_send(ssh);
e5574168 4351
4352 crWaitUntil(ispkt);
51470298 4353 if (ssh->pktin.type != s->kex_reply_value) {
6b5cf8b4 4354 bombout(("expected key exchange reply packet from server"));
7ffdbc1a 4355 crStop(0);
7cca0d81 4356 }
0016d70b 4357 ssh_pkt_getstring(ssh, &s->hostkeydata, &s->hostkeylen);
51470298 4358 s->f = ssh2_pkt_getmp(ssh);
0016d70b 4359 ssh_pkt_getstring(ssh, &s->sigdata, &s->siglen);
e5574168 4360
27cd7fc2 4361 s->K = dh_find_K(ssh->kex_ctx, s->f);
e5574168 4362
51470298 4363 sha_string(&ssh->exhash, s->hostkeydata, s->hostkeylen);
4364 if (ssh->kex == &ssh_diffiehellman_gex) {
4365 sha_uint32(&ssh->exhash, s->pbits);
4366 sha_mpint(&ssh->exhash, s->p);
4367 sha_mpint(&ssh->exhash, s->g);
a92dd380 4368 }
51470298 4369 sha_mpint(&ssh->exhash, s->e);
4370 sha_mpint(&ssh->exhash, s->f);
4371 sha_mpint(&ssh->exhash, s->K);
4372 SHA_Final(&ssh->exhash, s->exchange_hash);
e5574168 4373
27cd7fc2 4374 dh_cleanup(ssh->kex_ctx);
fabd1805 4375 ssh->kex_ctx = NULL;
3709bfe9 4376
7cca0d81 4377#if 0
765c4200 4378 debug(("Exchange hash is:\n"));
51470298 4379 dmemdump(s->exchange_hash, 20);
7cca0d81 4380#endif
4381
51470298 4382 s->hkey = ssh->hostkey->newkey(s->hostkeydata, s->hostkeylen);
4383 if (!s->hkey ||
4384 !ssh->hostkey->verifysig(s->hkey, s->sigdata, s->siglen,
d8baa528 4385 (char *)s->exchange_hash, 20)) {
6b5cf8b4 4386 bombout(("Server's host key did not match the signature supplied"));
7ffdbc1a 4387 crStop(0);
8d5de777 4388 }
e5574168 4389
4390 /*
7cca0d81 4391 * Authenticate remote host: verify host key. (We've already
4392 * checked the signature of the exchange hash.)
e5574168 4393 */
51470298 4394 s->keystr = ssh->hostkey->fmtkey(s->hkey);
4395 s->fingerprint = ssh->hostkey->fingerprint(s->hkey);
a8327734 4396 verify_ssh_host_key(ssh->frontend,
4397 ssh->savedhost, ssh->savedport, ssh->hostkey->keytype,
51470298 4398 s->keystr, s->fingerprint);
4399 if (s->first_kex) { /* don't bother logging this in rekeys */
5e0d7cb8 4400 logevent("Host key fingerprint is:");
51470298 4401 logevent(s->fingerprint);
5e0d7cb8 4402 }
51470298 4403 sfree(s->fingerprint);
4404 sfree(s->keystr);
4405 ssh->hostkey->freekey(s->hkey);
d39f364a 4406
4407 /*
7cca0d81 4408 * Send SSH2_MSG_NEWKEYS.
d39f364a 4409 */
51470298 4410 ssh2_pkt_init(ssh, SSH2_MSG_NEWKEYS);
4411 ssh2_pkt_send(ssh);
d39f364a 4412
4413 /*
8406eaf9 4414 * Expect SSH2_MSG_NEWKEYS from server.
4415 */
4416 crWaitUntil(ispkt);
51470298 4417 if (ssh->pktin.type != SSH2_MSG_NEWKEYS) {
6b5cf8b4 4418 bombout(("expected new-keys packet from server"));
7ffdbc1a 4419 crStop(0);
8406eaf9 4420 }
4421
4422 /*
d39f364a 4423 * Create and initialise session keys.
4424 */
371e569c 4425 if (ssh->cs_cipher_ctx)
4426 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
51470298 4427 ssh->cscipher = s->cscipher_tobe;
371e569c 4428 ssh->cs_cipher_ctx = ssh->cscipher->make_context();
e0e1a00d 4429
371e569c 4430 if (ssh->sc_cipher_ctx)
4431 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
51470298 4432 ssh->sccipher = s->sccipher_tobe;
371e569c 4433 ssh->sc_cipher_ctx = ssh->sccipher->make_context();
e0e1a00d 4434
4435 if (ssh->cs_mac_ctx)
4436 ssh->csmac->free_context(ssh->cs_mac_ctx);
51470298 4437 ssh->csmac = s->csmac_tobe;
e0e1a00d 4438 ssh->cs_mac_ctx = ssh->csmac->make_context();
4439
4440 if (ssh->sc_mac_ctx)
4441 ssh->scmac->free_context(ssh->sc_mac_ctx);
51470298 4442 ssh->scmac = s->scmac_tobe;
e0e1a00d 4443 ssh->sc_mac_ctx = ssh->scmac->make_context();
4444
5366aed8 4445 if (ssh->cs_comp_ctx)
4446 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
51470298 4447 ssh->cscomp = s->cscomp_tobe;
5366aed8 4448 ssh->cs_comp_ctx = ssh->cscomp->compress_init();
4449
4450 if (ssh->sc_comp_ctx)
4451 ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
51470298 4452 ssh->sccomp = s->sccomp_tobe;
5366aed8 4453 ssh->sc_comp_ctx = ssh->sccomp->decompress_init();
4454
d39f364a 4455 /*
5e0d7cb8 4456 * Set IVs after keys. Here we use the exchange hash from the
4457 * _first_ key exchange.
d39f364a 4458 */
51470298 4459 {
4460 unsigned char keyspace[40];
4461 if (s->first_kex)
4462 memcpy(ssh->v2_session_id, s->exchange_hash,
4463 sizeof(s->exchange_hash));
4464 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'C',keyspace);
371e569c 4465 ssh->cscipher->setkey(ssh->cs_cipher_ctx, keyspace);
51470298 4466 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'D',keyspace);
371e569c 4467 ssh->sccipher->setkey(ssh->sc_cipher_ctx, keyspace);
51470298 4468 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'A',keyspace);
371e569c 4469 ssh->cscipher->setiv(ssh->cs_cipher_ctx, keyspace);
51470298 4470 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'B',keyspace);
371e569c 4471 ssh->sccipher->setiv(ssh->sc_cipher_ctx, keyspace);
51470298 4472 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'E',keyspace);
e0e1a00d 4473 ssh->csmac->setkey(ssh->cs_mac_ctx, keyspace);
51470298 4474 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'F',keyspace);
e0e1a00d 4475 ssh->scmac->setkey(ssh->sc_mac_ctx, keyspace);
51470298 4476 }
57356d63 4477 logeventf(ssh, "Initialised %.200s client->server encryption",
4478 ssh->cscipher->text_name);
4479 logeventf(ssh, "Initialised %.200s server->client encryption",
4480 ssh->sccipher->text_name);
4481 if (ssh->cscomp->text_name)
4482 logeventf(ssh, "Initialised %s compression",
4483 ssh->cscomp->text_name);
4484 if (ssh->sccomp->text_name)
4485 logeventf(ssh, "Initialised %s decompression",
4486 ssh->sccomp->text_name);
679539d7 4487 freebn(s->f);
679539d7 4488 freebn(s->K);
b3949e7e 4489 if (ssh->kex == &ssh_diffiehellman_gex) {
4490 freebn(s->g);
4491 freebn(s->p);
4492 }
d39f364a 4493
033b4cef 4494 /*
0db56f73 4495 * If this is the first key exchange phase, we must pass the
4496 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
4497 * wants to see it but because it will need time to initialise
4498 * itself before it sees an actual packet. In subsequent key
4499 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
4500 * it would only confuse the layer above.
4501 */
51470298 4502 if (!s->first_kex) {
32874aea 4503 crReturn(0);
0db56f73 4504 }
51470298 4505 s->first_kex = 0;
0db56f73 4506
4507 /*
7cca0d81 4508 * Now we're encrypting. Begin returning 1 to the protocol main
4509 * function so that other things can run on top of the
4510 * transport. If we ever see a KEXINIT, we must go back to the
4511 * start.
033b4cef 4512 */
51470298 4513 while (!(ispkt && ssh->pktin.type == SSH2_MSG_KEXINIT)) {
32874aea 4514 crReturn(1);
e96adf72 4515 }
5e0d7cb8 4516 logevent("Server initiated key re-exchange");
7cca0d81 4517 goto begin_key_exchange;
e5574168 4518
4519 crFinish(1);
4520}
4521
7cca0d81 4522/*
783415f8 4523 * Add data to an SSH2 channel output buffer.
4524 */
32874aea 4525static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
4526 int len)
4527{
5471d09a 4528 bufchain_add(&c->v.v2.outbuffer, buf, len);
783415f8 4529}
4530
4531/*
4532 * Attempt to send data on an SSH2 channel.
4533 */
5471d09a 4534static int ssh2_try_send(struct ssh_channel *c)
32874aea 4535{
51470298 4536 Ssh ssh = c->ssh;
4537
5471d09a 4538 while (c->v.v2.remwindow > 0 && bufchain_size(&c->v.v2.outbuffer) > 0) {
4539 int len;
4540 void *data;
4541 bufchain_prefix(&c->v.v2.outbuffer, &data, &len);
4542 if ((unsigned)len > c->v.v2.remwindow)
4543 len = c->v.v2.remwindow;
4544 if ((unsigned)len > c->v.v2.remmaxpkt)
4545 len = c->v.v2.remmaxpkt;
51470298 4546 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_DATA);
4547 ssh2_pkt_adduint32(ssh, c->remoteid);
4548 ssh2_pkt_addstring_start(ssh);
4549 ssh2_pkt_addstring_data(ssh, data, len);
4550 ssh2_pkt_send(ssh);
5471d09a 4551 bufchain_consume(&c->v.v2.outbuffer, len);
4552 c->v.v2.remwindow -= len;
4553 }
4554
4555 /*
4556 * After having sent as much data as we can, return the amount
4557 * still buffered.
4558 */
4559 return bufchain_size(&c->v.v2.outbuffer);
4560}
4561
4562/*
4563 * Potentially enlarge the window on an SSH2 channel.
4564 */
4565static void ssh2_set_window(struct ssh_channel *c, unsigned newwin)
4566{
51470298 4567 Ssh ssh = c->ssh;
4568
6b69f42e 4569 /*
4570 * Never send WINDOW_ADJUST for a channel that the remote side
4571 * already thinks it's closed; there's no point, since it won't
4572 * be sending any more data anyway.
4573 */
4574 if (c->closes != 0)
4575 return;
4576
5471d09a 4577 if (newwin > c->v.v2.locwindow) {
51470298 4578 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST);
4579 ssh2_pkt_adduint32(ssh, c->remoteid);
4580 ssh2_pkt_adduint32(ssh, newwin - c->v.v2.locwindow);
4581 ssh2_pkt_send(ssh);
5471d09a 4582 c->v.v2.locwindow = newwin;
783415f8 4583 }
4584}
4585
4586/*
7cca0d81 4587 * Handle the SSH2 userauth and connection layers.
4588 */
51470298 4589static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
7cca0d81 4590{
51470298 4591 struct do_ssh2_authconn_state {
4592 enum {
4593 AUTH_INVALID, AUTH_PUBLICKEY_AGENT, AUTH_PUBLICKEY_FILE,
4594 AUTH_PASSWORD,
4595 AUTH_KEYBOARD_INTERACTIVE
4596 } method;
4597 enum {
4598 AUTH_TYPE_NONE,
4599 AUTH_TYPE_PUBLICKEY,
4600 AUTH_TYPE_PUBLICKEY_OFFER_LOUD,
4601 AUTH_TYPE_PUBLICKEY_OFFER_QUIET,
4602 AUTH_TYPE_PASSWORD,
4603 AUTH_TYPE_KEYBOARD_INTERACTIVE,
4604 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
4605 } type;
4606 int gotit, need_pw, can_pubkey, can_passwd, can_keyb_inter;
4607 int tried_pubkey_config, tried_agent, tried_keyb_inter;
4608 int kbd_inter_running;
4609 int we_are_in;
4610 int num_prompts, curr_prompt, echo;
4611 char username[100];
4612 int got_username;
85fdbe25 4613 char pwprompt[512];
51470298 4614 char password[100];
4615 void *publickey_blob;
4616 int publickey_bloblen;
4617 unsigned char request[5], *response, *p;
4618 int responselen;
4619 int keyi, nkeys;
4620 int authed;
4621 char *pkblob, *alg, *commentp;
4622 int pklen, alglen, commentlen;
4623 int siglen, retlen, len;
4624 char *q, *agentreq, *ret;
4625 int try_send;
4626 };
4627 crState(do_ssh2_authconn_state);
4628
4629 crBegin(ssh->do_ssh2_authconn_crstate);
e5574168 4630
7cca0d81 4631 /*
4632 * Request userauth protocol, and await a response to it.
4633 */
51470298 4634 ssh2_pkt_init(ssh, SSH2_MSG_SERVICE_REQUEST);
4635 ssh2_pkt_addstring(ssh, "ssh-userauth");
4636 ssh2_pkt_send(ssh);
7cca0d81 4637 crWaitUntilV(ispkt);
51470298 4638 if (ssh->pktin.type != SSH2_MSG_SERVICE_ACCEPT) {
6b5cf8b4 4639 bombout(("Server refused user authentication protocol"));
7ffdbc1a 4640 crStopV;
8d5de777 4641 }
7cca0d81 4642
4643 /*
1408a877 4644 * We repeat this whole loop, including the username prompt,
4645 * until we manage a successful authentication. If the user
51470298 4646 * types the wrong _password_, they can be sent back to the
4647 * beginning to try another username, if this is configured on.
4648 * (If they specify a username in the config, they are never
4649 * asked, even if they do give a wrong password.)
1408a877 4650 *
4651 * I think this best serves the needs of
4652 *
4653 * - the people who have no configuration, no keys, and just
4654 * want to try repeated (username,password) pairs until they
4655 * type both correctly
4656 *
4657 * - people who have keys and configuration but occasionally
4658 * need to fall back to passwords
4659 *
4660 * - people with a key held in Pageant, who might not have
4661 * logged in to a particular machine before; so they want to
4662 * type a username, and then _either_ their key will be
4663 * accepted, _or_ they will type a password. If they mistype
4664 * the username they will want to be able to get back and
4665 * retype it!
7cca0d81 4666 */
51470298 4667 s->username[0] = '\0';
4668 s->got_username = FALSE;
1408a877 4669 do {
1408a877 4670 /*
4671 * Get a username.
4672 */
86916870 4673 if (s->got_username && !ssh->cfg.change_username) {
5bb641e1 4674 /*
4675 * We got a username last time round this loop, and
4676 * with change_username turned off we don't try to get
4677 * it again.
4678 */
86916870 4679 } else if ((flags & FLAG_INTERACTIVE) && !*ssh->cfg.username) {
c0a81592 4680 if (ssh_get_line && !ssh_getline_pw_only) {
32874aea 4681 if (!ssh_get_line("login as: ",
51470298 4682 s->username, sizeof(s->username), FALSE)) {
32874aea 4683 /*
4684 * get_line failed to get a username.
4685 * Terminate.
4686 */
4687 logevent("No username provided. Abandoning session.");
3bb2f322 4688 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 4689 crStopV;
32874aea 4690 }
4691 } else {
51470298 4692 int ret; /* need not be saved across crReturn */
4693 c_write_str(ssh, "login as: ");
4694 ssh->send_ok = 1;
4695 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
0405e71f 4696 do {
32874aea 4697 crWaitUntilV(!ispkt);
51470298 4698 ret = process_userpass_input(ssh, in, inlen);
0405e71f 4699 } while (ret == 0);
4700 if (ret < 0)
4701 cleanup_exit(0);
4ca0c9d1 4702 c_write_str(ssh, "\r\n");
32874aea 4703 }
51470298 4704 s->username[strcspn(s->username, "\n\r")] = '\0';
7cca0d81 4705 } else {
57356d63 4706 char *stuff;
86916870 4707 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
51470298 4708 s->username[sizeof(s->username)-1] = '\0';
65a22376 4709 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
57356d63 4710 stuff = dupprintf("Using username \"%s\".\r\n", s->username);
51470298 4711 c_write_str(ssh, stuff);
57356d63 4712 sfree(stuff);
7cca0d81 4713 }
4714 }
51470298 4715 s->got_username = TRUE;
7cca0d81 4716
65a22376 4717 /*
1408a877 4718 * Send an authentication request using method "none": (a)
4719 * just in case it succeeds, and (b) so that we know what
4720 * authentication methods we can usefully try next.
65a22376 4721 */
51470298 4722 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4723
4724 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4725 ssh2_pkt_addstring(ssh, s->username);
4726 ssh2_pkt_addstring(ssh, "ssh-connection");/* service requested */
4727 ssh2_pkt_addstring(ssh, "none"); /* method */
4728 ssh2_pkt_send(ssh);
4729 s->type = AUTH_TYPE_NONE;
4730 s->gotit = FALSE;
4731 s->we_are_in = FALSE;
4732
4733 s->tried_pubkey_config = FALSE;
4734 s->tried_agent = FALSE;
4735 s->tried_keyb_inter = FALSE;
4736 s->kbd_inter_running = FALSE;
86916870 4737 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
9a30e26b 4738 if (!filename_is_null(ssh->cfg.keyfile)) {
231ee168 4739 int keytype;
6c6d9ed9 4740 logeventf(ssh, "Reading private key file \"%.150s\"",
4741 filename_to_str(&ssh->cfg.keyfile));
9a30e26b 4742 keytype = key_type(&ssh->cfg.keyfile);
51470298 4743 if (keytype == SSH_KEYTYPE_SSH2) {
4744 s->publickey_blob =
9a30e26b 4745 ssh2_userkey_loadpub(&ssh->cfg.keyfile, NULL,
222d54dc 4746 &s->publickey_bloblen, NULL);
51470298 4747 } else {
57356d63 4748 char *msgbuf;
c2ad7d0d 4749 logeventf(ssh, "Unable to use this key file (%s)",
a8327734 4750 key_type_to_str(keytype));
57356d63 4751 msgbuf = dupprintf("Unable to use key file \"%.150s\""
6c6d9ed9 4752 " (%s)\r\n",
4753 filename_to_str(&ssh->cfg.keyfile),
57356d63 4754 key_type_to_str(keytype));
51470298 4755 c_write_str(ssh, msgbuf);
57356d63 4756 sfree(msgbuf);
51470298 4757 s->publickey_blob = NULL;
231ee168 4758 }
396778f1 4759 } else
51470298 4760 s->publickey_blob = NULL;
65a22376 4761
1408a877 4762 while (1) {
4763 /*
4764 * Wait for the result of the last authentication request.
4765 */
51470298 4766 if (!s->gotit)
1408a877 4767 crWaitUntilV(ispkt);
51470298 4768 while (ssh->pktin.type == SSH2_MSG_USERAUTH_BANNER) {
32874aea 4769 char *banner;
4770 int size;
4771 /*
4772 * Don't show the banner if we're operating in
4773 * non-verbose non-interactive mode. (It's probably
4774 * a script, which means nobody will read the
4775 * banner _anyway_, and moreover the printing of
4776 * the banner will screw up processing on the
4777 * output of (say) plink.)
4778 */
4779 if (flags & (FLAG_VERBOSE | FLAG_INTERACTIVE)) {
0016d70b 4780 ssh_pkt_getstring(ssh, &banner, &size);
32874aea 4781 if (banner)
51470298 4782 c_write_untrusted(ssh, banner, size);
32874aea 4783 }
1408a877 4784 crWaitUntilV(ispkt);
4785 }
51470298 4786 if (ssh->pktin.type == SSH2_MSG_USERAUTH_SUCCESS) {
1408a877 4787 logevent("Access granted");
51470298 4788 s->we_are_in = TRUE;
1408a877 4789 break;
4790 }
65a22376 4791
51470298 4792 if (s->kbd_inter_running &&
4793 ssh->pktin.type == SSH2_MSG_USERAUTH_INFO_REQUEST) {
b3186d64 4794 /*
45068b27 4795 * This is either a further set-of-prompts packet
4796 * in keyboard-interactive authentication, or it's
4797 * the same one and we came back here with `gotit'
4798 * set. In the former case, we must reset the
4799 * curr_prompt variable.
b3186d64 4800 */
51470298 4801 if (!s->gotit)
4802 s->curr_prompt = 0;
4803 } else if (ssh->pktin.type != SSH2_MSG_USERAUTH_FAILURE) {
6b5cf8b4 4804 bombout(("Strange packet received during authentication: type %d",
51470298 4805 ssh->pktin.type));
7ffdbc1a 4806 crStopV;
65a22376 4807 }
4808
51470298 4809 s->gotit = FALSE;
65a22376 4810
1408a877 4811 /*
4812 * OK, we're now sitting on a USERAUTH_FAILURE message, so
4813 * we can look at the string in it and know what we can
4814 * helpfully try next.
4815 */
51470298 4816 if (ssh->pktin.type == SSH2_MSG_USERAUTH_FAILURE) {
1408a877 4817 char *methods;
4818 int methlen;
0016d70b 4819 ssh_pkt_getstring(ssh, &methods, &methlen);
51470298 4820 s->kbd_inter_running = FALSE;
4821 if (!ssh2_pkt_getbool(ssh)) {
1408a877 4822 /*
4823 * We have received an unequivocal Access
4824 * Denied. This can translate to a variety of
4825 * messages:
4826 *
4827 * - if we'd just tried "none" authentication,
4828 * it's not worth printing anything at all
4829 *
4830 * - if we'd just tried a public key _offer_,
4831 * the message should be "Server refused our
4832 * key" (or no message at all if the key
4833 * came from Pageant)
4834 *
4835 * - if we'd just tried anything else, the
4836 * message really should be "Access denied".
4837 *
4838 * Additionally, if we'd just tried password
4839 * authentication, we should break out of this
4840 * whole loop so as to go back to the username
4841 * prompt.
4842 */
51470298 4843 if (s->type == AUTH_TYPE_NONE) {
1408a877 4844 /* do nothing */
51470298 4845 } else if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD ||
4846 s->type == AUTH_TYPE_PUBLICKEY_OFFER_QUIET) {
4847 if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD)
4848 c_write_str(ssh, "Server refused our key\r\n");
1408a877 4849 logevent("Server refused public key");
51470298 4850 } else if (s->type==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET) {
4bdf7c46 4851 /* server declined keyboard-interactive; ignore */
1408a877 4852 } else {
51470298 4853 c_write_str(ssh, "Access denied\r\n");
1408a877 4854 logevent("Access denied");
51470298 4855 if (s->type == AUTH_TYPE_PASSWORD) {
4856 s->we_are_in = FALSE;
1408a877 4857 break;
4858 }
4859 }
4860 } else {
51470298 4861 c_write_str(ssh, "Further authentication required\r\n");
1408a877 4862 logevent("Further authentication required");
4863 }
65a22376 4864
51470298 4865 s->can_pubkey =
32874aea 4866 in_commasep_string("publickey", methods, methlen);
51470298 4867 s->can_passwd =
32874aea 4868 in_commasep_string("password", methods, methlen);
86916870 4869 s->can_keyb_inter = ssh->cfg.try_ki_auth &&
761187b6 4870 in_commasep_string("keyboard-interactive", methods, methlen);
1408a877 4871 }
65a22376 4872
51470298 4873 s->method = 0;
4874 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
954a9540 4875 s->need_pw = FALSE;
65a22376 4876
0405e71f 4877 /*
4878 * Most password/passphrase prompts will be
4879 * non-echoing, so we set this to 0 by default.
4880 * Exception is that some keyboard-interactive prompts
4881 * can be echoing, in which case we'll set this to 1.
4882 */
51470298 4883 s->echo = 0;
0405e71f 4884
51470298 4885 if (!s->method && s->can_pubkey &&
4886 agent_exists() && !s->tried_agent) {
1983e559 4887 /*
4888 * Attempt public-key authentication using Pageant.
4889 */
1983e559 4890 void *r;
51470298 4891 s->authed = FALSE;
1983e559 4892
51470298 4893 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4894 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
00db133f 4895
51470298 4896 s->tried_agent = TRUE;
1983e559 4897
4898 logevent("Pageant is running. Requesting keys.");
4899
4900 /* Request the keys held by the agent. */
51470298 4901 PUT_32BIT(s->request, 1);
4902 s->request[4] = SSH2_AGENTC_REQUEST_IDENTITIES;
839f10db 4903 if (!agent_query(s->request, 5, &r, &s->responselen,
4904 ssh_agent_callback, ssh)) {
4905 do {
4906 crReturnV;
4907 if (ispkt) {
4908 bombout(("Unexpected data from server while"
4909 " waiting for agent response"));
4910 crStopV;
4911 }
4912 } while (ispkt || inlen > 0);
4913 r = ssh->agent_response;
4914 s->responselen = ssh->agent_response_len;
4915 }
51470298 4916 s->response = (unsigned char *) r;
4917 if (s->response && s->responselen >= 5 &&
4918 s->response[4] == SSH2_AGENT_IDENTITIES_ANSWER) {
4919 s->p = s->response + 5;
4920 s->nkeys = GET_32BIT(s->p);
4921 s->p += 4;
32874aea 4922 {
4923 char buf[64];
51470298 4924 sprintf(buf, "Pageant has %d SSH2 keys", s->nkeys);
32874aea 4925 logevent(buf);
4926 }
51470298 4927 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
2d466ffd 4928 void *vret;
1983e559 4929
32874aea 4930 {
4931 char buf[64];
51470298 4932 sprintf(buf, "Trying Pageant key #%d", s->keyi);
32874aea 4933 logevent(buf);
4934 }
51470298 4935 s->pklen = GET_32BIT(s->p);
4936 s->p += 4;
4937 if (s->publickey_blob &&
4938 s->pklen == s->publickey_bloblen &&
4939 !memcmp(s->p, s->publickey_blob,
4940 s->publickey_bloblen)) {
396778f1 4941 logevent("This key matches configured key file");
51470298 4942 s->tried_pubkey_config = 1;
396778f1 4943 }
d8baa528 4944 s->pkblob = (char *)s->p;
51470298 4945 s->p += s->pklen;
4946 s->alglen = GET_32BIT(s->pkblob);
4947 s->alg = s->pkblob + 4;
4948 s->commentlen = GET_32BIT(s->p);
4949 s->p += 4;
d8baa528 4950 s->commentp = (char *)s->p;
51470298 4951 s->p += s->commentlen;
4952 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4953 ssh2_pkt_addstring(ssh, s->username);
4954 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
4955 ssh2_pkt_addstring(ssh, "publickey"); /* method */
4956 ssh2_pkt_addbool(ssh, FALSE); /* no signature included */
4957 ssh2_pkt_addstring_start(ssh);
4958 ssh2_pkt_addstring_data(ssh, s->alg, s->alglen);
4959 ssh2_pkt_addstring_start(ssh);
4960 ssh2_pkt_addstring_data(ssh, s->pkblob, s->pklen);
4961 ssh2_pkt_send(ssh);
1983e559 4962
4963 crWaitUntilV(ispkt);
51470298 4964 if (ssh->pktin.type != SSH2_MSG_USERAUTH_PK_OK) {
1983e559 4965 logevent("Key refused");
4966 continue;
4967 }
4968
32874aea 4969 if (flags & FLAG_VERBOSE) {
51470298 4970 c_write_str(ssh, "Authenticating with "
4971 "public key \"");
4972 c_write(ssh, s->commentp, s->commentlen);
4973 c_write_str(ssh, "\" from agent\r\n");
32874aea 4974 }
1983e559 4975
4976 /*
4977 * Server is willing to accept the key.
4978 * Construct a SIGN_REQUEST.
4979 */
51470298 4980 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4981 ssh2_pkt_addstring(ssh, s->username);
4982 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
4983 ssh2_pkt_addstring(ssh, "publickey"); /* method */
4984 ssh2_pkt_addbool(ssh, TRUE);
4985 ssh2_pkt_addstring_start(ssh);
4986 ssh2_pkt_addstring_data(ssh, s->alg, s->alglen);
4987 ssh2_pkt_addstring_start(ssh);
4988 ssh2_pkt_addstring_data(ssh, s->pkblob, s->pklen);
4989
4990 s->siglen = ssh->pktout.length - 5 + 4 + 20;
dda87a28 4991 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
4992 s->siglen -= 4;
51470298 4993 s->len = 1; /* message type */
4994 s->len += 4 + s->pklen; /* key blob */
4995 s->len += 4 + s->siglen; /* data to sign */
4996 s->len += 4; /* flags */
3d88e64d 4997 s->agentreq = snewn(4 + s->len, char);
51470298 4998 PUT_32BIT(s->agentreq, s->len);
4999 s->q = s->agentreq + 4;
5000 *s->q++ = SSH2_AGENTC_SIGN_REQUEST;
5001 PUT_32BIT(s->q, s->pklen);
5002 s->q += 4;
5003 memcpy(s->q, s->pkblob, s->pklen);
5004 s->q += s->pklen;
5005 PUT_32BIT(s->q, s->siglen);
5006 s->q += 4;
1983e559 5007 /* Now the data to be signed... */
dda87a28 5008 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
5009 PUT_32BIT(s->q, 20);
5010 s->q += 4;
5011 }
51470298 5012 memcpy(s->q, ssh->v2_session_id, 20);
5013 s->q += 20;
5014 memcpy(s->q, ssh->pktout.data + 5,
5015 ssh->pktout.length - 5);
5016 s->q += ssh->pktout.length - 5;
1983e559 5017 /* And finally the (zero) flags word. */
51470298 5018 PUT_32BIT(s->q, 0);
839f10db 5019 if (!agent_query(s->agentreq, s->len + 4,
5020 &vret, &s->retlen,
5021 ssh_agent_callback, ssh)) {
5022 do {
5023 crReturnV;
5024 if (ispkt) {
5025 bombout(("Unexpected data from server"
5026 " while waiting for agent"
5027 " response"));
5028 crStopV;
5029 }
5030 } while (ispkt || inlen > 0);
5031 vret = ssh->agent_response;
5032 s->retlen = ssh->agent_response_len;
5033 }
51470298 5034 s->ret = vret;
5035 sfree(s->agentreq);
5036 if (s->ret) {
5037 if (s->ret[4] == SSH2_AGENT_SIGN_RESPONSE) {
1983e559 5038 logevent("Sending Pageant's response");
51470298 5039 ssh2_add_sigblob(ssh, s->pkblob, s->pklen,
5040 s->ret + 9,
5041 GET_32BIT(s->ret + 5));
5042 ssh2_pkt_send(ssh);
5043 s->authed = TRUE;
1983e559 5044 break;
5045 } else {
32874aea 5046 logevent
5047 ("Pageant failed to answer challenge");
51470298 5048 sfree(s->ret);
1983e559 5049 }
5050 }
5051 }
51470298 5052 if (s->authed)
1983e559 5053 continue;
5054 }
29b1d0b3 5055 sfree(s->response);
1983e559 5056 }
5057
51470298 5058 if (!s->method && s->can_pubkey && s->publickey_blob
5059 && !s->tried_pubkey_config) {
1408a877 5060 unsigned char *pub_blob;
5061 char *algorithm, *comment;
5062 int pub_blob_len;
65a22376 5063
51470298 5064 s->tried_pubkey_config = TRUE;
65a22376 5065
51470298 5066 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
5067 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
00db133f 5068
65a22376 5069 /*
1408a877 5070 * Try the public key supplied in the configuration.
5071 *
5072 * First, offer the public blob to see if the server is
5073 * willing to accept it.
65a22376 5074 */
d8baa528 5075 pub_blob =
9a30e26b 5076 (unsigned char *)ssh2_userkey_loadpub(&ssh->cfg.keyfile,
d8baa528 5077 &algorithm,
222d54dc 5078 &pub_blob_len,
5079 NULL);
1408a877 5080 if (pub_blob) {
51470298 5081 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
5082 ssh2_pkt_addstring(ssh, s->username);
5083 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
5084 ssh2_pkt_addstring(ssh, "publickey"); /* method */
5085 ssh2_pkt_addbool(ssh, FALSE); /* no signature included */
5086 ssh2_pkt_addstring(ssh, algorithm);
5087 ssh2_pkt_addstring_start(ssh);
d8baa528 5088 ssh2_pkt_addstring_data(ssh, (char *)pub_blob,
5089 pub_blob_len);
51470298 5090 ssh2_pkt_send(ssh);
32874aea 5091 logevent("Offered public key"); /* FIXME */
1408a877 5092
5093 crWaitUntilV(ispkt);
51470298 5094 if (ssh->pktin.type != SSH2_MSG_USERAUTH_PK_OK) {
5095 s->gotit = TRUE;
5096 s->type = AUTH_TYPE_PUBLICKEY_OFFER_LOUD;
32874aea 5097 continue; /* key refused; give up on it */
1408a877 5098 }
65a22376 5099
1408a877 5100 logevent("Offer of public key accepted");
65a22376 5101 /*
1408a877 5102 * Actually attempt a serious authentication using
5103 * the key.
65a22376 5104 */
9a30e26b 5105 if (ssh2_userkey_encrypted(&ssh->cfg.keyfile, &comment)) {
51470298 5106 sprintf(s->pwprompt,
32874aea 5107 "Passphrase for key \"%.100s\": ",
5108 comment);
51470298 5109 s->need_pw = TRUE;
1408a877 5110 } else {
51470298 5111 s->need_pw = FALSE;
1408a877 5112 }
4e520718 5113 if (flags & FLAG_VERBOSE) {
5114 c_write_str(ssh, "Authenticating with public key \"");
5115 c_write_str(ssh, comment);
5116 c_write_str(ssh, "\"\r\n");
5117 }
51470298 5118 s->method = AUTH_PUBLICKEY_FILE;
65a22376 5119 }
1408a877 5120 }
5121
51470298 5122 if (!s->method && s->can_keyb_inter && !s->tried_keyb_inter) {
5123 s->method = AUTH_KEYBOARD_INTERACTIVE;
5124 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
5125 s->tried_keyb_inter = TRUE;
af659722 5126
51470298 5127 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
5128 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
00db133f 5129
51470298 5130 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
5131 ssh2_pkt_addstring(ssh, s->username);
5132 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
5133 ssh2_pkt_addstring(ssh, "keyboard-interactive"); /* method */
5134 ssh2_pkt_addstring(ssh, ""); /* lang */
5135 ssh2_pkt_addstring(ssh, "");
5136 ssh2_pkt_send(ssh);
af659722 5137
5138 crWaitUntilV(ispkt);
51470298 5139 if (ssh->pktin.type != SSH2_MSG_USERAUTH_INFO_REQUEST) {
5140 if (ssh->pktin.type == SSH2_MSG_USERAUTH_FAILURE)
5141 s->gotit = TRUE;
af659722 5142 logevent("Keyboard-interactive authentication refused");
51470298 5143 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET;
af659722 5144 continue;
5145 }
5146
51470298 5147 s->kbd_inter_running = TRUE;
5148 s->curr_prompt = 0;
af659722 5149 }
5150
51470298 5151 if (s->kbd_inter_running) {
5152 s->method = AUTH_KEYBOARD_INTERACTIVE;
5153 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
5154 s->tried_keyb_inter = TRUE;
af659722 5155
51470298 5156 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
5157 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
00db133f 5158
51470298 5159 if (s->curr_prompt == 0) {
45068b27 5160 /*
5161 * We've got a fresh USERAUTH_INFO_REQUEST.
5162 * Display header data, and start going through
5163 * the prompts.
5164 */
5165 char *name, *inst, *lang;
5166 int name_len, inst_len, lang_len;
5167
0016d70b 5168 ssh_pkt_getstring(ssh, &name, &name_len);
5169 ssh_pkt_getstring(ssh, &inst, &inst_len);
5170 ssh_pkt_getstring(ssh, &lang, &lang_len);
45068b27 5171 if (name_len > 0) {
51470298 5172 c_write_untrusted(ssh, name, name_len);
5173 c_write_str(ssh, "\r\n");
45068b27 5174 }
5175 if (inst_len > 0) {
51470298 5176 c_write_untrusted(ssh, inst, inst_len);
5177 c_write_str(ssh, "\r\n");
45068b27 5178 }
0016d70b 5179 s->num_prompts = ssh_pkt_getuint32(ssh);
45068b27 5180 }
af659722 5181
45068b27 5182 /*
5183 * If there are prompts remaining in the packet,
5184 * display one and get a response.
5185 */
51470298 5186 if (s->curr_prompt < s->num_prompts) {
45068b27 5187 char *prompt;
5188 int prompt_len;
af659722 5189
0016d70b 5190 ssh_pkt_getstring(ssh, &prompt, &prompt_len);
45068b27 5191 if (prompt_len > 0) {
85fdbe25 5192 static const char trunc[] = "<prompt truncated>: ";
5193 static const int prlen = sizeof(s->pwprompt) -
5194 lenof(trunc);
5195 if (prompt_len > prlen) {
5196 memcpy(s->pwprompt, prompt, prlen);
5197 strcpy(s->pwprompt + prlen, trunc);
5198 } else {
5199 memcpy(s->pwprompt, prompt, prompt_len);
5200 s->pwprompt[prompt_len] = '\0';
5201 }
45068b27 5202 } else {
51470298 5203 strcpy(s->pwprompt,
45068b27 5204 "<server failed to send prompt>: ");
5205 }
51470298 5206 s->echo = ssh2_pkt_getbool(ssh);
5207 s->need_pw = TRUE;
45068b27 5208 } else
51470298 5209 s->need_pw = FALSE;
af659722 5210 }
5211
51470298 5212 if (!s->method && s->can_passwd) {
5213 s->method = AUTH_PASSWORD;
5214 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
5215 ssh->pkt_ctx |= SSH2_PKTCTX_PASSWORD;
5216 sprintf(s->pwprompt, "%.90s@%.90s's password: ", s->username,
5217 ssh->savedhost);
5218 s->need_pw = TRUE;
1408a877 5219 }
5220
51470298 5221 if (s->need_pw) {
fa17a66e 5222 if (ssh_get_line) {
51470298 5223 if (!ssh_get_line(s->pwprompt, s->password,
5224 sizeof(s->password), TRUE)) {
1408a877 5225 /*
fa17a66e 5226 * get_line failed to get a password (for
5227 * example because one was supplied on the
5228 * command line which has already failed to
5229 * work). Terminate.
1408a877 5230 */
51470298 5231 ssh2_pkt_init(ssh, SSH2_MSG_DISCONNECT);
5232 ssh2_pkt_adduint32(ssh,SSH2_DISCONNECT_BY_APPLICATION);
5233 ssh2_pkt_addstring(ssh, "No more passwords available"
5234 " to try");
5235 ssh2_pkt_addstring(ssh, "en"); /* language tag */
5236 ssh2_pkt_send(ssh);
247308b5 5237 logevent("Unable to authenticate");
a8327734 5238 connection_fatal(ssh->frontend,
5239 "Unable to authenticate");
3bb2f322 5240 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 5241 crStopV;
1408a877 5242 }
5243 } else {
51470298 5244 int ret; /* need not be saved across crReturn */
5245 c_write_untrusted(ssh, s->pwprompt, strlen(s->pwprompt));
5246 ssh->send_ok = 1;
1408a877 5247
51470298 5248 setup_userpass_input(ssh, s->password,
5249 sizeof(s->password), s->echo);
0405e71f 5250 do {
1408a877 5251 crWaitUntilV(!ispkt);
51470298 5252 ret = process_userpass_input(ssh, in, inlen);
0405e71f 5253 } while (ret == 0);
5254 if (ret < 0)
5255 cleanup_exit(0);
51470298 5256 c_write_str(ssh, "\r\n");
65a22376 5257 }
65a22376 5258 }
65a22376 5259
51470298 5260 if (s->method == AUTH_PUBLICKEY_FILE) {
1408a877 5261 /*
5262 * We have our passphrase. Now try the actual authentication.
5263 */
5264 struct ssh2_userkey *key;
222d54dc 5265 const char *error = NULL;
65a22376 5266
222d54dc 5267 key = ssh2_load_userkey(&ssh->cfg.keyfile, s->password,
5268 &error);
1408a877 5269 if (key == SSH2_WRONG_PASSPHRASE || key == NULL) {
5270 if (key == SSH2_WRONG_PASSPHRASE) {
51470298 5271 c_write_str(ssh, "Wrong passphrase\r\n");
5272 s->tried_pubkey_config = FALSE;
1408a877 5273 } else {
222d54dc 5274 c_write_str(ssh, "Unable to load private key (");
5275 c_write_str(ssh, error);
5276 c_write_str(ssh, ")\r\n");
51470298 5277 s->tried_pubkey_config = TRUE;
1408a877 5278 }
5279 /* Send a spurious AUTH_NONE to return to the top. */
51470298 5280 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
5281 ssh2_pkt_addstring(ssh, s->username);
5282 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
5283 ssh2_pkt_addstring(ssh, "none"); /* method */
5284 ssh2_pkt_send(ssh);
5285 s->type = AUTH_TYPE_NONE;
1408a877 5286 } else {
1dd353b5 5287 unsigned char *pkblob, *sigblob, *sigdata;
5288 int pkblob_len, sigblob_len, sigdata_len;
dda87a28 5289 int p;
65a22376 5290
1408a877 5291 /*
5292 * We have loaded the private key and the server
5293 * has announced that it's willing to accept it.
5294 * Hallelujah. Generate a signature and send it.
5295 */
51470298 5296 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
5297 ssh2_pkt_addstring(ssh, s->username);
5298 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
5299 ssh2_pkt_addstring(ssh, "publickey"); /* method */
5300 ssh2_pkt_addbool(ssh, TRUE);
5301 ssh2_pkt_addstring(ssh, key->alg->name);
1dd353b5 5302 pkblob = key->alg->public_blob(key->data, &pkblob_len);
51470298 5303 ssh2_pkt_addstring_start(ssh);
d8baa528 5304 ssh2_pkt_addstring_data(ssh, (char *)pkblob, pkblob_len);
1408a877 5305
5306 /*
5307 * The data to be signed is:
5308 *
5309 * string session-id
5310 *
5311 * followed by everything so far placed in the
5312 * outgoing packet.
5313 */
51470298 5314 sigdata_len = ssh->pktout.length - 5 + 4 + 20;
dda87a28 5315 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
5316 sigdata_len -= 4;
92d60585 5317 sigdata = snewn(sigdata_len, unsigned char);
dda87a28 5318 p = 0;
5319 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
5320 PUT_32BIT(sigdata+p, 20);
5321 p += 4;
5322 }
5323 memcpy(sigdata+p, ssh->v2_session_id, 20); p += 20;
5324 memcpy(sigdata+p, ssh->pktout.data + 5,
51470298 5325 ssh->pktout.length - 5);
dda87a28 5326 p += ssh->pktout.length - 5;
5327 assert(p == sigdata_len);
d8baa528 5328 sigblob = key->alg->sign(key->data, (char *)sigdata,
1dd353b5 5329 sigdata_len, &sigblob_len);
51470298 5330 ssh2_add_sigblob(ssh, pkblob, pkblob_len,
1dd353b5 5331 sigblob, sigblob_len);
5332 sfree(pkblob);
5333 sfree(sigblob);
1408a877 5334 sfree(sigdata);
5335
51470298 5336 ssh2_pkt_send(ssh);
5337 s->type = AUTH_TYPE_PUBLICKEY;
75374b2f 5338 key->alg->freekey(key->data);
1408a877 5339 }
51470298 5340 } else if (s->method == AUTH_PASSWORD) {
65a22376 5341 /*
1408a877 5342 * We send the password packet lumped tightly together with
5343 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
5344 * string long enough to make the total length of the two
5345 * packets constant. This should ensure that a passive
5346 * listener doing traffic analyis can't work out the length
5347 * of the password.
5348 *
5349 * For this to work, we need an assumption about the
5350 * maximum length of the password packet. I think 256 is
5351 * pretty conservative. Anyone using a password longer than
5352 * that probably doesn't have much to worry about from
5353 * people who find out how long their password is!
65a22376 5354 */
51470298 5355 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
5356 ssh2_pkt_addstring(ssh, s->username);
5357 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
5358 ssh2_pkt_addstring(ssh, "password");
5359 ssh2_pkt_addbool(ssh, FALSE);
5360 ssh2_pkt_addstring(ssh, s->password);
1409c1b3 5361 memset(s->password, 0, sizeof(s->password));
51470298 5362 ssh2_pkt_defer(ssh);
65a22376 5363 /*
1408a877 5364 * We'll include a string that's an exact multiple of the
5365 * cipher block size. If the cipher is NULL for some
5366 * reason, we don't do this trick at all because we gain
5367 * nothing by it.
65a22376 5368 */
51470298 5369 if (ssh->cscipher) {
32874aea 5370 int stringlen, i;
5371
51470298 5372 stringlen = (256 - ssh->deferred_len);
5373 stringlen += ssh->cscipher->blksize - 1;
5374 stringlen -= (stringlen % ssh->cscipher->blksize);
5375 if (ssh->cscomp) {
32874aea 5376 /*
5377 * Temporarily disable actual compression,
5378 * so we can guarantee to get this string
5379 * exactly the length we want it. The
5380 * compression-disabling routine should
5381 * return an integer indicating how many
5382 * bytes we should adjust our string length
5383 * by.
5384 */
5366aed8 5385 stringlen -=
5386 ssh->cscomp->disable_compression(ssh->cs_comp_ctx);
32874aea 5387 }
51470298 5388 ssh2_pkt_init(ssh, SSH2_MSG_IGNORE);
5389 ssh2_pkt_addstring_start(ssh);
6e9e9520 5390 for (i = 0; i < stringlen; i++) {
32874aea 5391 char c = (char) random_byte();
51470298 5392 ssh2_pkt_addstring_data(ssh, &c, 1);
65a22376 5393 }
51470298 5394 ssh2_pkt_defer(ssh);
65a22376 5395 }
51470298 5396 ssh_pkt_defersend(ssh);
0d43337a 5397 logevent("Sent password");
51470298 5398 s->type = AUTH_TYPE_PASSWORD;
5399 } else if (s->method == AUTH_KEYBOARD_INTERACTIVE) {
5400 if (s->curr_prompt == 0) {
5401 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_INFO_RESPONSE);
5402 ssh2_pkt_adduint32(ssh, s->num_prompts);
45068b27 5403 }
51470298 5404 if (s->need_pw) { /* only add pw if we just got one! */
5405 ssh2_pkt_addstring(ssh, s->password);
5406 memset(s->password, 0, sizeof(s->password));
5407 s->curr_prompt++;
45068b27 5408 }
51470298 5409 if (s->curr_prompt >= s->num_prompts) {
5410 ssh2_pkt_send(ssh);
45068b27 5411 } else {
5412 /*
5413 * If there are prompts remaining, we set
5414 * `gotit' so that we won't attempt to get
5415 * another packet. Then we go back round the
5416 * loop and will end up retrieving another
5417 * prompt out of the existing packet. Funky or
5418 * what?
5419 */
51470298 5420 s->gotit = TRUE;
45068b27 5421 }
51470298 5422 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
1408a877 5423 } else {
51470298 5424 c_write_str(ssh, "No supported authentication methods"
5425 " left to try!\r\n");
5426 logevent("No supported authentications offered."
5427 " Disconnecting");
5428 ssh2_pkt_init(ssh, SSH2_MSG_DISCONNECT);
5429 ssh2_pkt_adduint32(ssh, SSH2_DISCONNECT_BY_APPLICATION);
5430 ssh2_pkt_addstring(ssh, "No supported authentication"
5431 " methods available");
5432 ssh2_pkt_addstring(ssh, "en"); /* language tag */
5433 ssh2_pkt_send(ssh);
3bb2f322 5434 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 5435 crStopV;
65a22376 5436 }
65a22376 5437 }
51470298 5438 } while (!s->we_are_in);
7cca0d81 5439
5440 /*
5441 * Now we're authenticated for the connection protocol. The
5442 * connection protocol will automatically have started at this
5443 * point; there's no need to send SERVICE_REQUEST.
5444 */
5445
5446 /*
5447 * So now create a channel with a session in it.
5448 */
51470298 5449 ssh->channels = newtree234(ssh_channelcmp);
3d88e64d 5450 ssh->mainchan = snew(struct ssh_channel);
51470298 5451 ssh->mainchan->ssh = ssh;
5452 ssh->mainchan->localid = alloc_channel_id(ssh);
5453 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_OPEN);
5454 ssh2_pkt_addstring(ssh, "session");
5455 ssh2_pkt_adduint32(ssh, ssh->mainchan->localid);
5456 ssh->mainchan->v.v2.locwindow = OUR_V2_WINSIZE;
5457 ssh2_pkt_adduint32(ssh, ssh->mainchan->v.v2.locwindow);/* our window size */
5458 ssh2_pkt_adduint32(ssh, 0x4000UL); /* our max pkt size */
5459 ssh2_pkt_send(ssh);
7cca0d81 5460 crWaitUntilV(ispkt);
51470298 5461 if (ssh->pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
6b5cf8b4 5462 bombout(("Server refused to open a session"));
7ffdbc1a 5463 crStopV;
32874aea 5464 /* FIXME: error data comes back in FAILURE packet */
7cca0d81 5465 }
0016d70b 5466 if (ssh_pkt_getuint32(ssh) != ssh->mainchan->localid) {
6b5cf8b4 5467 bombout(("Server's channel confirmation cited wrong channel"));
7ffdbc1a 5468 crStopV;
7cca0d81 5469 }
0016d70b 5470 ssh->mainchan->remoteid = ssh_pkt_getuint32(ssh);
51470298 5471 ssh->mainchan->type = CHAN_MAINSESSION;
5472 ssh->mainchan->closes = 0;
0016d70b 5473 ssh->mainchan->v.v2.remwindow = ssh_pkt_getuint32(ssh);
5474 ssh->mainchan->v.v2.remmaxpkt = ssh_pkt_getuint32(ssh);
51470298 5475 bufchain_init(&ssh->mainchan->v.v2.outbuffer);
5476 add234(ssh->channels, ssh->mainchan);
7cca0d81 5477 logevent("Opened channel for session");
5478
5479 /*
783415f8 5480 * Potentially enable X11 forwarding.
5481 */
86916870 5482 if (ssh->cfg.x11_forward) {
32874aea 5483 char proto[20], data[64];
5484 logevent("Requesting X11 forwarding");
302121de 5485 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
86916870 5486 data, sizeof(data), ssh->cfg.x11_auth);
5487 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
51470298 5488 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
5489 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
5490 ssh2_pkt_addstring(ssh, "x11-req");
5491 ssh2_pkt_addbool(ssh, 1); /* want reply */
5492 ssh2_pkt_addbool(ssh, 0); /* many connections */
5493 ssh2_pkt_addstring(ssh, proto);
5494 ssh2_pkt_addstring(ssh, data);
86916870 5495 ssh2_pkt_adduint32(ssh, x11_get_screen_number(ssh->cfg.x11_display));
51470298 5496 ssh2_pkt_send(ssh);
32874aea 5497
5498 do {
5499 crWaitUntilV(ispkt);
51470298 5500 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
0016d70b 5501 unsigned i = ssh_pkt_getuint32(ssh);
32874aea 5502 struct ssh_channel *c;
51470298 5503 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5504 if (!c)
5505 continue; /* nonexistent channel */
0016d70b 5506 c->v.v2.remwindow += ssh_pkt_getuint32(ssh);
32874aea 5507 }
51470298 5508 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
32874aea 5509
51470298 5510 if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
5511 if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 5512 bombout(("Unexpected response to X11 forwarding request:"
51470298 5513 " packet type %d", ssh->pktin.type));
7ffdbc1a 5514 crStopV;
32874aea 5515 }
5516 logevent("X11 forwarding refused");
5517 } else {
5518 logevent("X11 forwarding enabled");
51470298 5519 ssh->X11_fwd_enabled = TRUE;
32874aea 5520 }
783415f8 5521 }
5522
5523 /*
bc240b21 5524 * Enable port forwardings.
5525 */
5526 {
bc240b21 5527 char type;
5528 int n;
a4fc0d74 5529 int sport,dport,sserv,dserv;
6ee9b735 5530 char sports[256], dports[256], saddr[256], host[256];
bc240b21 5531
51470298 5532 ssh->rportfwds = newtree234(ssh_rportcmp_ssh2);
bc240b21 5533 /* Add port forwardings. */
86916870 5534 ssh->portfwd_strptr = ssh->cfg.portfwd;
51470298 5535 while (*ssh->portfwd_strptr) {
5536 type = *ssh->portfwd_strptr++;
6ee9b735 5537 saddr[0] = '\0';
bc240b21 5538 n = 0;
6ee9b735 5539 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != '\t') {
5540 if (*ssh->portfwd_strptr == ':') {
5541 /*
5542 * We've seen a colon in the middle of the
5543 * source port number. This means that
5544 * everything we've seen until now is the
5545 * source _address_, so we'll move it into
5546 * saddr and start sports from the beginning
5547 * again.
5548 */
5549 ssh->portfwd_strptr++;
5550 sports[n] = '\0';
5551 strcpy(saddr, sports);
5552 n = 0;
5553 }
5554 if (n < 255) sports[n++] = *ssh->portfwd_strptr++;
5555 }
bc240b21 5556 sports[n] = 0;
820ebe3b 5557 if (type != 'D') {
5558 if (*ssh->portfwd_strptr == '\t')
5559 ssh->portfwd_strptr++;
5560 n = 0;
5561 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != ':') {
5562 if (n < 255) host[n++] = *ssh->portfwd_strptr++;
5563 }
5564 host[n] = 0;
5565 if (*ssh->portfwd_strptr == ':')
5566 ssh->portfwd_strptr++;
5567 n = 0;
5568 while (*ssh->portfwd_strptr) {
5569 if (n < 255) dports[n++] = *ssh->portfwd_strptr++;
5570 }
5571 dports[n] = 0;
51470298 5572 ssh->portfwd_strptr++;
820ebe3b 5573 dport = atoi(dports);
5574 dserv = 0;
5575 if (dport == 0) {
5576 dserv = 1;
5577 dport = net_service_lookup(dports);
5578 if (!dport) {
5579 logeventf(ssh, "Service lookup failed for destination"
5580 " port \"%s\"", dports);
5581 }
a4fc0d74 5582 }
820ebe3b 5583 } else {
5584 while (*ssh->portfwd_strptr) ssh->portfwd_strptr++;
7ffdbc1a 5585 dport = dserv = -1;
7d5b0f4d 5586 ssh->portfwd_strptr++; /* eat the NUL and move to next one */
a4fc0d74 5587 }
bc240b21 5588 sport = atoi(sports);
a4fc0d74 5589 sserv = 0;
5590 if (sport == 0) {
5591 sserv = 1;
68a49acb 5592 sport = net_service_lookup(sports);
5593 if (!sport) {
57356d63 5594 logeventf(ssh, "Service lookup failed for source"
5595 " port \"%s\"", sports);
a4fc0d74 5596 }
5597 }
bc240b21 5598 if (sport && dport) {
5599 if (type == 'L') {
6ee9b735 5600 pfd_addforward(host, dport, *saddr ? saddr : NULL,
e8fa8f62 5601 sport, ssh, &ssh->cfg);
6ee9b735 5602 logeventf(ssh, "Local port %.*s%.*s%.*s%.*s%d%.*s"
5603 " forwarding to %s:%.*s%.*s%d%.*s",
5604 (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
5605 (int)(*saddr?1:0), ":",
57356d63 5606 (int)(sserv ? strlen(sports) : 0), sports,
5607 sserv, "(", sport, sserv, ")",
5608 host,
5609 (int)(dserv ? strlen(dports) : 0), dports,
5610 dserv, "(", dport, dserv, ")");
820ebe3b 5611 } else if (type == 'D') {
5612 pfd_addforward(NULL, -1, *saddr ? saddr : NULL,
5613 sport, ssh, &ssh->cfg);
5614 logeventf(ssh, "Local port %.*s%.*s%.*s%.*s%d%.*s"
5615 " doing SOCKS dynamic forwarding",
5616 (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
5617 (int)(*saddr?1:0), ":",
5618 (int)(sserv ? strlen(sports) : 0), sports,
5619 sserv, "(", sport, sserv, ")");
bc240b21 5620 } else {
5621 struct ssh_rportfwd *pf;
3d88e64d 5622 pf = snew(struct ssh_rportfwd);
bc240b21 5623 strcpy(pf->dhost, host);
5624 pf->dport = dport;
5625 pf->sport = sport;
51470298 5626 if (add234(ssh->rportfwds, pf) != pf) {
57356d63 5627 logeventf(ssh, "Duplicate remote port forwarding"
5628 " to %s:%d", host, dport);
bc240b21 5629 sfree(pf);
5630 } else {
6ee9b735 5631 logeventf(ssh, "Requesting remote port "
5632 "%.*s%.*s%.*s%.*s%d%.*s"
57356d63 5633 " forward to %s:%.*s%.*s%d%.*s",
6ee9b735 5634 (int)(*saddr?strlen(saddr):0),
5635 *saddr?saddr:NULL,
5636 (int)(*saddr?1:0), ":",
57356d63 5637 (int)(sserv ? strlen(sports) : 0), sports,
5638 sserv, "(", sport, sserv, ")",
5639 host,
5640 (int)(dserv ? strlen(dports) : 0), dports,
5641 dserv, "(", dport, dserv, ")");
51470298 5642 ssh2_pkt_init(ssh, SSH2_MSG_GLOBAL_REQUEST);
5643 ssh2_pkt_addstring(ssh, "tcpip-forward");
5644 ssh2_pkt_addbool(ssh, 1);/* want reply */
6ee9b735 5645 if (*saddr)
5646 ssh2_pkt_addstring(ssh, saddr);
86916870 5647 if (ssh->cfg.rport_acceptall)
51470298 5648 ssh2_pkt_addstring(ssh, "0.0.0.0");
beefa433 5649 else
51470298 5650 ssh2_pkt_addstring(ssh, "127.0.0.1");
5651 ssh2_pkt_adduint32(ssh, sport);
5652 ssh2_pkt_send(ssh);
bc240b21 5653
5654 do {
5655 crWaitUntilV(ispkt);
51470298 5656 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
0016d70b 5657 unsigned i = ssh_pkt_getuint32(ssh);
bc240b21 5658 struct ssh_channel *c;
51470298 5659 c = find234(ssh->channels, &i, ssh_channelfind);
bc240b21 5660 if (!c)
5661 continue;/* nonexistent channel */
0016d70b 5662 c->v.v2.remwindow += ssh_pkt_getuint32(ssh);
bc240b21 5663 }
51470298 5664 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
bc240b21 5665
51470298 5666 if (ssh->pktin.type != SSH2_MSG_REQUEST_SUCCESS) {
5667 if (ssh->pktin.type != SSH2_MSG_REQUEST_FAILURE) {
6b5cf8b4 5668 bombout(("Unexpected response to port "
c9886e66 5669 "forwarding request: packet type %d",
51470298 5670 ssh->pktin.type));
7ffdbc1a 5671 crStopV;
bc240b21 5672 }
5673 logevent("Server refused this port forwarding");
5674 } else {
5675 logevent("Remote port forwarding enabled");
5676 }
5677 }
5678 }
5679 }
5680 }
5681 }
5682
5683 /*
36c2a3e9 5684 * Potentially enable agent forwarding.
5685 */
86916870 5686 if (ssh->cfg.agentfwd && agent_exists()) {
32874aea 5687 logevent("Requesting OpenSSH-style agent forwarding");
51470298 5688 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
5689 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
5690 ssh2_pkt_addstring(ssh, "auth-agent-req@openssh.com");
5691 ssh2_pkt_addbool(ssh, 1); /* want reply */
5692 ssh2_pkt_send(ssh);
32874aea 5693
5694 do {
5695 crWaitUntilV(ispkt);
51470298 5696 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
0016d70b 5697 unsigned i = ssh_pkt_getuint32(ssh);
32874aea 5698 struct ssh_channel *c;
51470298 5699 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5700 if (!c)
5701 continue; /* nonexistent channel */
0016d70b 5702 c->v.v2.remwindow += ssh_pkt_getuint32(ssh);
32874aea 5703 }
51470298 5704 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
32874aea 5705
51470298 5706 if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
5707 if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 5708 bombout(("Unexpected response to agent forwarding request:"
51470298 5709 " packet type %d", ssh->pktin.type));
7ffdbc1a 5710 crStopV;
32874aea 5711 }
5712 logevent("Agent forwarding refused");
5713 } else {
5714 logevent("Agent forwarding enabled");
51470298 5715 ssh->agentfwd_enabled = TRUE;
32874aea 5716 }
36c2a3e9 5717 }
5718
5719 /*
7cca0d81 5720 * Now allocate a pty for the session.
5721 */
86916870 5722 if (!ssh->cfg.nopty) {
a5dd8467 5723 /* Unpick the terminal-speed string. */
5724 /* XXX perhaps we should allow no speeds to be sent. */
db219738 5725 ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
5726 sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
a5dd8467 5727 /* Build the pty request. */
51470298 5728 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
5729 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid); /* recipient channel */
5730 ssh2_pkt_addstring(ssh, "pty-req");
5731 ssh2_pkt_addbool(ssh, 1); /* want reply */
86916870 5732 ssh2_pkt_addstring(ssh, ssh->cfg.termtype);
51470298 5733 ssh2_pkt_adduint32(ssh, ssh->term_width);
5734 ssh2_pkt_adduint32(ssh, ssh->term_height);
5735 ssh2_pkt_adduint32(ssh, 0); /* pixel width */
5736 ssh2_pkt_adduint32(ssh, 0); /* pixel height */
5737 ssh2_pkt_addstring_start(ssh);
a5dd8467 5738 ssh2_pkt_addbyte(ssh, 128); /* TTY_OP_ISPEED */
db219738 5739 ssh2_pkt_adduint32(ssh, ssh->ispeed);
a5dd8467 5740 ssh2_pkt_addbyte(ssh, 129); /* TTY_OP_OSPEED */
db219738 5741 ssh2_pkt_adduint32(ssh, ssh->ospeed);
a5dd8467 5742 ssh2_pkt_addstring_data(ssh, "\0", 1); /* TTY_OP_END */
51470298 5743 ssh2_pkt_send(ssh);
5744 ssh->state = SSH_STATE_INTERMED;
32874aea 5745
5746 do {
5747 crWaitUntilV(ispkt);
51470298 5748 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
0016d70b 5749 unsigned i = ssh_pkt_getuint32(ssh);
32874aea 5750 struct ssh_channel *c;
51470298 5751 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5752 if (!c)
5753 continue; /* nonexistent channel */
0016d70b 5754 c->v.v2.remwindow += ssh_pkt_getuint32(ssh);
32874aea 5755 }
51470298 5756 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
32874aea 5757
51470298 5758 if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
5759 if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 5760 bombout(("Unexpected response to pty request:"
51470298 5761 " packet type %d", ssh->pktin.type));
7ffdbc1a 5762 crStopV;
32874aea 5763 }
51470298 5764 c_write_str(ssh, "Server refused to allocate pty\r\n");
5765 ssh->editing = ssh->echoing = 1;
32874aea 5766 } else {
a5dd8467 5767 logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
db219738 5768 ssh->ospeed, ssh->ispeed);
32874aea 5769 }
0965bee0 5770 } else {
51470298 5771 ssh->editing = ssh->echoing = 1;
7cca0d81 5772 }
5773
5774 /*
fd5e5847 5775 * Start a shell or a remote command. We may have to attempt
5776 * this twice if the config data has provided a second choice
5777 * of command.
7cca0d81 5778 */
fd5e5847 5779 while (1) {
5780 int subsys;
5781 char *cmd;
5782
51470298 5783 if (ssh->fallback_cmd) {
86916870 5784 subsys = ssh->cfg.ssh_subsys2;
5785 cmd = ssh->cfg.remote_cmd_ptr2;
fd5e5847 5786 } else {
86916870 5787 subsys = ssh->cfg.ssh_subsys;
5788 cmd = ssh->cfg.remote_cmd_ptr;
fd5e5847 5789 }
5790
51470298 5791 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
5792 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid); /* recipient channel */
fd5e5847 5793 if (subsys) {
51470298 5794 ssh2_pkt_addstring(ssh, "subsystem");
5795 ssh2_pkt_addbool(ssh, 1); /* want reply */
5796 ssh2_pkt_addstring(ssh, cmd);
fd5e5847 5797 } else if (*cmd) {
51470298 5798 ssh2_pkt_addstring(ssh, "exec");
5799 ssh2_pkt_addbool(ssh, 1); /* want reply */
5800 ssh2_pkt_addstring(ssh, cmd);
fd5e5847 5801 } else {
51470298 5802 ssh2_pkt_addstring(ssh, "shell");
5803 ssh2_pkt_addbool(ssh, 1); /* want reply */
32874aea 5804 }
51470298 5805 ssh2_pkt_send(ssh);
fd5e5847 5806 do {
5807 crWaitUntilV(ispkt);
51470298 5808 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
0016d70b 5809 unsigned i = ssh_pkt_getuint32(ssh);
fd5e5847 5810 struct ssh_channel *c;
51470298 5811 c = find234(ssh->channels, &i, ssh_channelfind);
fd5e5847 5812 if (!c)
5813 continue; /* nonexistent channel */
0016d70b 5814 c->v.v2.remwindow += ssh_pkt_getuint32(ssh);
fd5e5847 5815 }
51470298 5816 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
5817 if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
5818 if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 5819 bombout(("Unexpected response to shell/command request:"
51470298 5820 " packet type %d", ssh->pktin.type));
7ffdbc1a 5821 crStopV;
fd5e5847 5822 }
5823 /*
5824 * We failed to start the command. If this is the
5825 * fallback command, we really are finished; if it's
5826 * not, and if the fallback command exists, try falling
5827 * back to it before complaining.
5828 */
86916870 5829 if (!ssh->fallback_cmd && ssh->cfg.remote_cmd_ptr2 != NULL) {
fd5e5847 5830 logevent("Primary command failed; attempting fallback");
51470298 5831 ssh->fallback_cmd = TRUE;
fd5e5847 5832 continue;
5833 }
6b5cf8b4 5834 bombout(("Server refused to start a shell/command"));
7ffdbc1a 5835 crStopV;
fd5e5847 5836 } else {
5837 logevent("Started a shell/command");
32874aea 5838 }
fd5e5847 5839 break;
7cca0d81 5840 }
5841
51470298 5842 ssh->state = SSH_STATE_SESSION;
5843 if (ssh->size_needed)
5844 ssh_size(ssh, ssh->term_width, ssh->term_height);
5845 if (ssh->eof_needed)
5846 ssh_special(ssh, TS_EOF);
6e48c3fe 5847
7cca0d81 5848 /*
5849 * Transfer data!
5850 */
b9d7bcad 5851 if (ssh->ldisc)
5852 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
51470298 5853 ssh->send_ok = 1;
7cca0d81 5854 while (1) {
e5574168 5855 crReturnV;
51470298 5856 s->try_send = FALSE;
7cca0d81 5857 if (ispkt) {
51470298 5858 if (ssh->pktin.type == SSH2_MSG_CHANNEL_DATA ||
5859 ssh->pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
32874aea 5860 char *data;
5861 int length;
0016d70b 5862 unsigned i = ssh_pkt_getuint32(ssh);
32874aea 5863 struct ssh_channel *c;
51470298 5864 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5865 if (!c)
5866 continue; /* nonexistent channel */
51470298 5867 if (ssh->pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
0016d70b 5868 ssh_pkt_getuint32(ssh) != SSH2_EXTENDED_DATA_STDERR)
32874aea 5869 continue; /* extended but not stderr */
0016d70b 5870 ssh_pkt_getstring(ssh, &data, &length);
32874aea 5871 if (data) {
7ffdbc1a 5872 int bufsize = 0;
5471d09a 5873 c->v.v2.locwindow -= length;
32874aea 5874 switch (c->type) {
5875 case CHAN_MAINSESSION:
5471d09a 5876 bufsize =
51470298 5877 from_backend(ssh->frontend, ssh->pktin.type ==
5471d09a 5878 SSH2_MSG_CHANNEL_EXTENDED_DATA,
5879 data, length);
32874aea 5880 break;
5881 case CHAN_X11:
5471d09a 5882 bufsize = x11_send(c->u.x11.s, data, length);
32874aea 5883 break;
d74d141c 5884 case CHAN_SOCKDATA:
5471d09a 5885 bufsize = pfd_send(c->u.pfd.s, data, length);
bc240b21 5886 break;
36c2a3e9 5887 case CHAN_AGENT:
32874aea 5888 while (length > 0) {
5889 if (c->u.a.lensofar < 4) {
5890 int l = min(4 - c->u.a.lensofar, length);
5891 memcpy(c->u.a.msglen + c->u.a.lensofar,
5892 data, l);
5893 data += l;
5894 length -= l;
5895 c->u.a.lensofar += l;
5896 }
5897 if (c->u.a.lensofar == 4) {
5898 c->u.a.totallen =
5899 4 + GET_32BIT(c->u.a.msglen);
3d88e64d 5900 c->u.a.message = snewn(c->u.a.totallen,
5901 unsigned char);
32874aea 5902 memcpy(c->u.a.message, c->u.a.msglen, 4);
5903 }
5904 if (c->u.a.lensofar >= 4 && length > 0) {
5905 int l =
5906 min(c->u.a.totallen - c->u.a.lensofar,
5907 length);
5908 memcpy(c->u.a.message + c->u.a.lensofar,
5909 data, l);
5910 data += l;
5911 length -= l;
5912 c->u.a.lensofar += l;
5913 }
5914 if (c->u.a.lensofar == c->u.a.totallen) {
839f10db 5915 void *reply;
32874aea 5916 int replylen;
839f10db 5917 if (agent_query(c->u.a.message,
5918 c->u.a.totallen,
5919 &reply, &replylen,
5920 ssh_agentf_callback, c))
5921 ssh_agentf_callback(c, reply, replylen);
32874aea 5922 sfree(c->u.a.message);
5923 c->u.a.lensofar = 0;
5924 }
5925 }
5471d09a 5926 bufsize = 0;
32874aea 5927 break;
5928 }
5929 /*
5471d09a 5930 * If we are not buffering too much data,
5931 * enlarge the window again at the remote side.
32874aea 5932 */
5471d09a 5933 if (bufsize < OUR_V2_WINSIZE)
5934 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
32874aea 5935 }
51470298 5936 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_EOF) {
0016d70b 5937 unsigned i = ssh_pkt_getuint32(ssh);
32874aea 5938 struct ssh_channel *c;
5939
51470298 5940 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5941 if (!c)
5942 continue; /* nonexistent channel */
5943
5944 if (c->type == CHAN_X11) {
5945 /*
5946 * Remote EOF on an X11 channel means we should
5947 * wrap up and close the channel ourselves.
5948 */
5949 x11_close(c->u.x11.s);
5950 sshfwd_close(c);
5951 } else if (c->type == CHAN_AGENT) {
36c2a3e9 5952 sshfwd_close(c);
d74d141c 5953 } else if (c->type == CHAN_SOCKDATA) {
bc240b21 5954 pfd_close(c->u.pfd.s);
5955 sshfwd_close(c);
36c2a3e9 5956 }
51470298 5957 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_CLOSE) {
0016d70b 5958 unsigned i = ssh_pkt_getuint32(ssh);
32874aea 5959 struct ssh_channel *c;
5960
51470298 5961 c = find234(ssh->channels, &i, ssh_channelfind);
d0d844c1 5962 if (!c || ((int)c->remoteid) == -1) {
6b5cf8b4 5963 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
d0d844c1 5964 c ? "half-open" : "nonexistent", i));
7ffdbc1a 5965 crStopV;
d0d844c1 5966 }
32874aea 5967 /* Do pre-close processing on the channel. */
5968 switch (c->type) {
5969 case CHAN_MAINSESSION:
5970 break; /* nothing to see here, move along */
5971 case CHAN_X11:
92f157bd 5972 if (c->u.x11.s != NULL)
5973 x11_close(c->u.x11.s);
5974 sshfwd_close(c);
32874aea 5975 break;
5976 case CHAN_AGENT:
92f157bd 5977 sshfwd_close(c);
32874aea 5978 break;
d74d141c 5979 case CHAN_SOCKDATA:
92f157bd 5980 if (c->u.pfd.s != NULL)
5981 pfd_close(c->u.pfd.s);
5982 sshfwd_close(c);
bc240b21 5983 break;
32874aea 5984 }
92f157bd 5985 if (c->closes == 0) {
51470298 5986 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_CLOSE);
5987 ssh2_pkt_adduint32(ssh, c->remoteid);
5988 ssh2_pkt_send(ssh);
92f157bd 5989 }
51470298 5990 del234(ssh->channels, c);
5471d09a 5991 bufchain_clear(&c->v.v2.outbuffer);
32874aea 5992 sfree(c);
5993
5994 /*
5995 * See if that was the last channel left open.
5996 */
51470298 5997 if (count234(ssh->channels) == 0) {
3bb2f322 5998 logevent("All channels closed. Disconnecting");
ca2914d1 5999#if 0
6000 /*
6001 * We used to send SSH_MSG_DISCONNECT here,
6002 * because I'd believed that _every_ conforming
6003 * SSH2 connection had to end with a disconnect
6004 * being sent by at least one side; apparently
6005 * I was wrong and it's perfectly OK to
6006 * unceremoniously slam the connection shut
6007 * when you're done, and indeed OpenSSH feels
6008 * this is more polite than sending a
6009 * DISCONNECT. So now we don't.
6010 */
51470298 6011 ssh2_pkt_init(ssh, SSH2_MSG_DISCONNECT);
6012 ssh2_pkt_adduint32(ssh, SSH2_DISCONNECT_BY_APPLICATION);
6013 ssh2_pkt_addstring(ssh, "All open channels closed");
6014 ssh2_pkt_addstring(ssh, "en"); /* language tag */
6015 ssh2_pkt_send(ssh);
ca2914d1 6016#endif
3bb2f322 6017 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 6018 crStopV;
32874aea 6019 }
6020 continue; /* remote sends close; ignore (FIXME) */
51470298 6021 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
0016d70b 6022 unsigned i = ssh_pkt_getuint32(ssh);
32874aea 6023 struct ssh_channel *c;
51470298 6024 c = find234(ssh->channels, &i, ssh_channelfind);
a6253970 6025 if (!c || c->closes)
6026 continue; /* nonexistent or closing channel */
0016d70b 6027 c->v.v2.remwindow += ssh_pkt_getuint32(ssh);
51470298 6028 s->try_send = TRUE;
6029 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
0016d70b 6030 unsigned i = ssh_pkt_getuint32(ssh);
bc240b21 6031 struct ssh_channel *c;
51470298 6032 c = find234(ssh->channels, &i, ssh_channelfind);
bc240b21 6033 if (!c)
6034 continue; /* nonexistent channel */
6035 if (c->type != CHAN_SOCKDATA_DORMANT)
6036 continue; /* dunno why they're confirming this */
0016d70b 6037 c->remoteid = ssh_pkt_getuint32(ssh);
bc240b21 6038 c->type = CHAN_SOCKDATA;
0016d70b 6039 c->v.v2.remwindow = ssh_pkt_getuint32(ssh);
6040 c->v.v2.remmaxpkt = ssh_pkt_getuint32(ssh);
4ed34d25 6041 if (c->u.pfd.s)
6042 pfd_confirm(c->u.pfd.s);
6043 if (c->closes) {
6044 /*
6045 * We have a pending close on this channel,
6046 * which we decided on before the server acked
6047 * the channel open. So now we know the
6048 * remoteid, we can close it again.
6049 */
51470298 6050 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_CLOSE);
6051 ssh2_pkt_adduint32(ssh, c->remoteid);
6052 ssh2_pkt_send(ssh);
4ed34d25 6053 }
51470298 6054 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_OPEN_FAILURE) {
0016d70b 6055 unsigned i = ssh_pkt_getuint32(ssh);
724cface 6056 struct ssh_channel *c;
51470298 6057 c = find234(ssh->channels, &i, ssh_channelfind);
724cface 6058 if (!c)
6059 continue; /* nonexistent channel */
6060 if (c->type != CHAN_SOCKDATA_DORMANT)
6061 continue; /* dunno why they're failing this */
6062
6063 logevent("Forwarded connection refused by server");
6064
6065 pfd_close(c->u.pfd.s);
6066
51470298 6067 del234(ssh->channels, c);
724cface 6068 sfree(c);
51470298 6069 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_REQUEST) {
ebb0a590 6070 unsigned localid;
6071 char *type;
6072 int typelen, want_reply;
6073 struct ssh_channel *c;
6074
0016d70b 6075 localid = ssh_pkt_getuint32(ssh);
6076 ssh_pkt_getstring(ssh, &type, &typelen);
51470298 6077 want_reply = ssh2_pkt_getbool(ssh);
ebb0a590 6078
6079 /*
6080 * First, check that the channel exists. Otherwise,
6081 * we can instantly disconnect with a rude message.
6082 */
51470298 6083 c = find234(ssh->channels, &localid, ssh_channelfind);
ebb0a590 6084 if (!c) {
6085 char buf[80];
6086 sprintf(buf, "Received channel request for nonexistent"
6087 " channel %d", localid);
6088 logevent(buf);
51470298 6089 ssh2_pkt_init(ssh, SSH2_MSG_DISCONNECT);
6090 ssh2_pkt_adduint32(ssh, SSH2_DISCONNECT_BY_APPLICATION);
6091 ssh2_pkt_addstring(ssh, buf);
6092 ssh2_pkt_addstring(ssh, "en"); /* language tag */
6093 ssh2_pkt_send(ssh);
6b5cf8b4 6094 connection_fatal(ssh->frontend, "%s", buf);
3bb2f322 6095 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 6096 crStopV;
ebb0a590 6097 }
6098
6099 /*
d8d6c7e5 6100 * Having got the channel number, we now look at
6101 * the request type string to see if it's something
6102 * we recognise.
ebb0a590 6103 */
d8d6c7e5 6104 if (typelen == 11 && !memcmp(type, "exit-status", 11) &&
51470298 6105 c == ssh->mainchan) {
d8d6c7e5 6106 /* We recognise "exit-status" on the primary channel. */
6107 char buf[100];
0016d70b 6108 ssh->exitcode = ssh_pkt_getuint32(ssh);
d8d6c7e5 6109 sprintf(buf, "Server sent command exit status %d",
51470298 6110 ssh->exitcode);
d8d6c7e5 6111 logevent(buf);
6112 if (want_reply) {
51470298 6113 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_SUCCESS);
6114 ssh2_pkt_adduint32(ssh, c->remoteid);
6115 ssh2_pkt_send(ssh);
d8d6c7e5 6116 }
6117 } else {
6118 /*
6119 * This is a channel request we don't know
6120 * about, so we now either ignore the request
6121 * or respond with CHANNEL_FAILURE, depending
6122 * on want_reply.
6123 */
6124 if (want_reply) {
51470298 6125 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_FAILURE);
6126 ssh2_pkt_adduint32(ssh, c->remoteid);
6127 ssh2_pkt_send(ssh);
d8d6c7e5 6128 }
ebb0a590 6129 }
51470298 6130 } else if (ssh->pktin.type == SSH2_MSG_GLOBAL_REQUEST) {
697d4856 6131 char *type;
6132 int typelen, want_reply;
6133
0016d70b 6134 ssh_pkt_getstring(ssh, &type, &typelen);
51470298 6135 want_reply = ssh2_pkt_getbool(ssh);
697d4856 6136
6137 /*
6138 * We currently don't support any global requests
6139 * at all, so we either ignore the request or
6140 * respond with REQUEST_FAILURE, depending on
6141 * want_reply.
6142 */
6143 if (want_reply) {
51470298 6144 ssh2_pkt_init(ssh, SSH2_MSG_REQUEST_FAILURE);
6145 ssh2_pkt_send(ssh);
697d4856 6146 }
51470298 6147 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_OPEN) {
32874aea 6148 char *type;
6149 int typelen;
b3ebaa28 6150 char *peeraddr;
6151 int peeraddrlen;
2e5b14c0 6152 int peerport;
32874aea 6153 char *error = NULL;
6154 struct ssh_channel *c;
bc240b21 6155 unsigned remid, winsize, pktsize;
0016d70b 6156 ssh_pkt_getstring(ssh, &type, &typelen);
3d88e64d 6157 c = snew(struct ssh_channel);
51470298 6158 c->ssh = ssh;
32874aea 6159
0016d70b 6160 remid = ssh_pkt_getuint32(ssh);
6161 winsize = ssh_pkt_getuint32(ssh);
6162 pktsize = ssh_pkt_getuint32(ssh);
bc240b21 6163
32874aea 6164 if (typelen == 3 && !memcmp(type, "x11", 3)) {
df85f78b 6165 char *addrstr;
6166
0016d70b 6167 ssh_pkt_getstring(ssh, &peeraddr, &peeraddrlen);
df85f78b 6168 addrstr = snewn(peeraddrlen+1, char);
b3ebaa28 6169 memcpy(addrstr, peeraddr, peeraddrlen);
5a9bf764 6170 addrstr[peeraddrlen] = '\0';
0016d70b 6171 peerport = ssh_pkt_getuint32(ssh);
b3ebaa28 6172
5a9bf764 6173 logeventf(ssh, "Received X11 connect request from %s:%d",
6174 addrstr, peerport);
6175
51470298 6176 if (!ssh->X11_fwd_enabled)
32874aea 6177 error = "X11 forwarding is not enabled";
86916870 6178 else if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
2e5b14c0 6179 ssh->x11auth, addrstr, peerport,
e8fa8f62 6180 &ssh->cfg) != NULL) {
32874aea 6181 error = "Unable to open an X11 connection";
6182 } else {
5a9bf764 6183 logevent("Opening X11 forward connection succeeded");
32874aea 6184 c->type = CHAN_X11;
6185 }
b3ebaa28 6186
6187 sfree(addrstr);
bc240b21 6188 } else if (typelen == 15 &&
6189 !memcmp(type, "forwarded-tcpip", 15)) {
6190 struct ssh_rportfwd pf, *realpf;
6191 char *dummy;
6192 int dummylen;
0016d70b 6193 ssh_pkt_getstring(ssh, &dummy, &dummylen);/* skip address */
6194 pf.sport = ssh_pkt_getuint32(ssh);
6195 ssh_pkt_getstring(ssh, &peeraddr, &peeraddrlen);
6196 peerport = ssh_pkt_getuint32(ssh);
51470298 6197 realpf = find234(ssh->rportfwds, &pf, NULL);
5a9bf764 6198 logeventf(ssh, "Received remote port %d open request "
6199 "from %s:%d", pf.sport, peeraddr, peerport);
bc240b21 6200 if (realpf == NULL) {
6201 error = "Remote port is not recognised";
6202 } else {
cbe2d68f 6203 const char *e = pfd_newconnect(&c->u.pfd.s,
6204 realpf->dhost,
6205 realpf->dport, c,
6206 &ssh->cfg);
5a9bf764 6207 logeventf(ssh, "Attempting to forward remote port to "
6208 "%s:%d", realpf->dhost, realpf->dport);
bc240b21 6209 if (e != NULL) {
57356d63 6210 logeventf(ssh, "Port open failed: %s", e);
bc240b21 6211 error = "Port open failed";
6212 } else {
6213 logevent("Forwarded port opened successfully");
6214 c->type = CHAN_SOCKDATA;
6215 }
6216 }
32874aea 6217 } else if (typelen == 22 &&
36c2a3e9 6218 !memcmp(type, "auth-agent@openssh.com", 3)) {
51470298 6219 if (!ssh->agentfwd_enabled)
32874aea 6220 error = "Agent forwarding is not enabled";
36c2a3e9 6221 else {
32874aea 6222 c->type = CHAN_AGENT; /* identify channel type */
36c2a3e9 6223 c->u.a.lensofar = 0;
32874aea 6224 }
6225 } else {
6226 error = "Unsupported channel type requested";
6227 }
6228
bc240b21 6229 c->remoteid = remid;
32874aea 6230 if (error) {
51470298 6231 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_OPEN_FAILURE);
6232 ssh2_pkt_adduint32(ssh, c->remoteid);
6233 ssh2_pkt_adduint32(ssh, SSH2_OPEN_CONNECT_FAILED);
6234 ssh2_pkt_addstring(ssh, error);
6235 ssh2_pkt_addstring(ssh, "en"); /* language tag */
6236 ssh2_pkt_send(ssh);
5a9bf764 6237 logeventf(ssh, "Rejected channel open: %s", error);
32874aea 6238 sfree(c);
6239 } else {
51470298 6240 c->localid = alloc_channel_id(ssh);
32874aea 6241 c->closes = 0;
5471d09a 6242 c->v.v2.locwindow = OUR_V2_WINSIZE;
6243 c->v.v2.remwindow = winsize;
6244 c->v.v2.remmaxpkt = pktsize;
6245 bufchain_init(&c->v.v2.outbuffer);
51470298 6246 add234(ssh->channels, c);
6247 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
6248 ssh2_pkt_adduint32(ssh, c->remoteid);
6249 ssh2_pkt_adduint32(ssh, c->localid);
6250 ssh2_pkt_adduint32(ssh, c->v.v2.locwindow);
6251 ssh2_pkt_adduint32(ssh, 0x4000UL); /* our max pkt size */
6252 ssh2_pkt_send(ssh);
32874aea 6253 }
7cca0d81 6254 } else {
6b5cf8b4 6255 bombout(("Strange packet received: type %d", ssh->pktin.type));
7ffdbc1a 6256 crStopV;
7cca0d81 6257 }
6258 } else {
32874aea 6259 /*
6260 * We have spare data. Add it to the channel buffer.
6261 */
d8baa528 6262 ssh2_add_channel_data(ssh->mainchan, (char *)in, inlen);
51470298 6263 s->try_send = TRUE;
32874aea 6264 }
51470298 6265 if (s->try_send) {
32874aea 6266 int i;
6267 struct ssh_channel *c;
6268 /*
6269 * Try to send data on all channels if we can.
6270 */
51470298 6271 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
a6253970 6272 int bufsize;
6273 if (c->closes)
6274 continue; /* don't send on closing channels */
6275 bufsize = ssh2_try_send(c);
5471d09a 6276 if (bufsize == 0) {
6277 switch (c->type) {
6278 case CHAN_MAINSESSION:
6279 /* stdin need not receive an unthrottle
6280 * notification since it will be polled */
6281 break;
6282 case CHAN_X11:
6283 x11_unthrottle(c->u.x11.s);
6284 break;
6285 case CHAN_AGENT:
6286 /* agent sockets are request/response and need no
6287 * buffer management */
6288 break;
6289 case CHAN_SOCKDATA:
6290 pfd_unthrottle(c->u.pfd.s);
6291 break;
6292 }
6293 }
6294 }
7cca0d81 6295 }
e5574168 6296 }
6297
6298 crFinishV;
6299}
6300
6301/*
7cca0d81 6302 * Handle the top-level SSH2 protocol.
6303 */
51470298 6304static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
7cca0d81 6305{
51470298 6306 if (do_ssh2_transport(ssh, in, inlen, ispkt) == 0)
32874aea 6307 return;
51470298 6308 do_ssh2_authconn(ssh, in, inlen, ispkt);
7cca0d81 6309}
6310
6311/*
8df7a775 6312 * Called to set up the connection.
374330e2 6313 *
6314 * Returns an error message, or NULL on success.
374330e2 6315 */
cbe2d68f 6316static const char *ssh_init(void *frontend_handle, void **backend_handle,
6317 Config *cfg,
79bf227b 6318 char *host, int port, char **realhost, int nodelay,
6319 int keepalive)
32874aea 6320{
cbe2d68f 6321 const char *p;
51470298 6322 Ssh ssh;
6323
3d88e64d 6324 ssh = snew(struct ssh_tag);
86916870 6325 ssh->cfg = *cfg; /* STRUCTURE COPY */
125105d1 6326 ssh->version = 0; /* when not ready yet */
51470298 6327 ssh->s = NULL;
6328 ssh->cipher = NULL;
371e569c 6329 ssh->v1_cipher_ctx = NULL;
0183b242 6330 ssh->crcda_ctx = NULL;
51470298 6331 ssh->cscipher = NULL;
371e569c 6332 ssh->cs_cipher_ctx = NULL;
51470298 6333 ssh->sccipher = NULL;
371e569c 6334 ssh->sc_cipher_ctx = NULL;
51470298 6335 ssh->csmac = NULL;
a8327734 6336 ssh->cs_mac_ctx = NULL;
51470298 6337 ssh->scmac = NULL;
e0e1a00d 6338 ssh->sc_mac_ctx = NULL;
51470298 6339 ssh->cscomp = NULL;
5366aed8 6340 ssh->cs_comp_ctx = NULL;
51470298 6341 ssh->sccomp = NULL;
5366aed8 6342 ssh->sc_comp_ctx = NULL;
51470298 6343 ssh->kex = NULL;
389aa499 6344 ssh->kex_ctx = NULL;
51470298 6345 ssh->hostkey = NULL;
6346 ssh->exitcode = -1;
6347 ssh->state = SSH_STATE_PREPACKET;
6348 ssh->size_needed = FALSE;
6349 ssh->eof_needed = FALSE;
b9d7bcad 6350 ssh->ldisc = NULL;
a8327734 6351 ssh->logctx = NULL;
51470298 6352 {
6353 static const struct Packet empty = { 0, 0, NULL, NULL, 0 };
6354 ssh->pktin = ssh->pktout = empty;
6355 }
6356 ssh->deferred_send_data = NULL;
6357 ssh->deferred_len = 0;
6358 ssh->deferred_size = 0;
6359 ssh->fallback_cmd = 0;
6360 ssh->pkt_ctx = 0;
302121de 6361 ssh->x11auth = NULL;
be738459 6362 ssh->v1_compressing = FALSE;
51470298 6363 ssh->v2_outgoing_sequence = 0;
6364 ssh->ssh1_rdpkt_crstate = 0;
6365 ssh->ssh2_rdpkt_crstate = 0;
6366 ssh->do_ssh_init_crstate = 0;
6367 ssh->ssh_gotdata_crstate = 0;
6368 ssh->ssh1_protocol_crstate = 0;
6369 ssh->do_ssh1_login_crstate = 0;
6370 ssh->do_ssh2_transport_crstate = 0;
6371 ssh->do_ssh2_authconn_crstate = 0;
6372 ssh->do_ssh_init_state = NULL;
6373 ssh->do_ssh1_login_state = NULL;
6374 ssh->do_ssh2_transport_state = NULL;
6375 ssh->do_ssh2_authconn_state = NULL;
6571dbfd 6376 ssh->mainchan = NULL;
968d2d92 6377 ssh->throttled_all = 0;
6378 ssh->v1_stdout_throttling = 0;
51470298 6379
6380 *backend_handle = ssh;
32874aea 6381
8f203108 6382#ifdef MSCRYPTOAPI
32874aea 6383 if (crypto_startup() == 0)
8f203108 6384 return "Microsoft high encryption pack not installed!";
6385#endif
374330e2 6386
51470298 6387 ssh->frontend = frontend_handle;
86916870 6388 ssh->term_width = ssh->cfg.width;
6389 ssh->term_height = ssh->cfg.height;
887035a5 6390
fabd1805 6391 ssh->channels = NULL;
6392 ssh->rportfwds = NULL;
6393
51470298 6394 ssh->send_ok = 0;
6395 ssh->editing = 0;
6396 ssh->echoing = 0;
6397 ssh->v1_throttle_count = 0;
6398 ssh->overall_bufsize = 0;
6399 ssh->fallback_cmd = 0;
8df7a775 6400
3648d4c5 6401 ssh->protocol = NULL;
6402
79bf227b 6403 p = connect_to_host(ssh, host, port, realhost, nodelay, keepalive);
fb09bf1c 6404 if (p != NULL)
6405 return p;
374330e2 6406
374330e2 6407 return NULL;
6408}
6409
fabd1805 6410static void ssh_free(void *handle)
6411{
6412 Ssh ssh = (Ssh) handle;
6413 struct ssh_channel *c;
6414 struct ssh_rportfwd *pf;
6415
6416 if (ssh->v1_cipher_ctx)
6417 ssh->cipher->free_context(ssh->v1_cipher_ctx);
6418 if (ssh->cs_cipher_ctx)
6419 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
6420 if (ssh->sc_cipher_ctx)
6421 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
6422 if (ssh->cs_mac_ctx)
6423 ssh->csmac->free_context(ssh->cs_mac_ctx);
6424 if (ssh->sc_mac_ctx)
6425 ssh->scmac->free_context(ssh->sc_mac_ctx);
29b1d0b3 6426 if (ssh->cs_comp_ctx) {
6427 if (ssh->cscomp)
6428 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
6429 else
6430 zlib_compress_cleanup(ssh->cs_comp_ctx);
6431 }
6432 if (ssh->sc_comp_ctx) {
6433 if (ssh->sccomp)
6434 ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
6435 else
6436 zlib_decompress_cleanup(ssh->sc_comp_ctx);
6437 }
fabd1805 6438 if (ssh->kex_ctx)
6439 dh_cleanup(ssh->kex_ctx);
6440 sfree(ssh->savedhost);
6441
6442 if (ssh->channels) {
6443 while ((c = delpos234(ssh->channels, 0)) != NULL) {
6444 switch (c->type) {
6445 case CHAN_X11:
6446 if (c->u.x11.s != NULL)
6447 x11_close(c->u.x11.s);
6448 break;
6449 case CHAN_SOCKDATA:
6450 if (c->u.pfd.s != NULL)
6451 pfd_close(c->u.pfd.s);
6452 break;
6453 }
6454 sfree(c);
6455 }
6456 freetree234(ssh->channels);
6457 }
6458
6459 if (ssh->rportfwds) {
6460 while ((pf = delpos234(ssh->rportfwds, 0)) != NULL)
6461 sfree(pf);
6462 freetree234(ssh->rportfwds);
6463 }
6464 sfree(ssh->deferred_send_data);
6465 if (ssh->x11auth)
6466 x11_free_auth(ssh->x11auth);
6467 sfree(ssh->do_ssh_init_state);
6468 sfree(ssh->do_ssh1_login_state);
6469 sfree(ssh->do_ssh2_transport_state);
6470 sfree(ssh->do_ssh2_authconn_state);
679539d7 6471 if (ssh->pktout.data) {
6472 sfree(ssh->pktout.data);
6473 ssh->pktout.data = NULL;
6474 }
6475 if (ssh->pktin.data) {
6476 sfree(ssh->pktin.data);
6477 ssh->pktin.data = NULL;
6478 }
6479 if (ssh->crcda_ctx) {
6480 crcda_free_context(ssh->crcda_ctx);
6481 ssh->crcda_ctx = NULL;
6482 }
fabd1805 6483 if (ssh->s)
36f94d1f 6484 ssh_do_close(ssh);
fabd1805 6485 sfree(ssh);
6486}
6487
374330e2 6488/*
86916870 6489 * Reconfigure the SSH backend.
6490 *
6491 * Currently, this function does nothing very useful. In future,
6492 * however, we could do some handy things with it. For example, we
6493 * could make the port forwarding configurer active in the Change
6494 * Settings box, and this routine could close down existing
6495 * forwardings and open up new ones in response to changes.
6496 */
6497static void ssh_reconfig(void *handle, Config *cfg)
6498{
6499 Ssh ssh = (Ssh) handle;
6500 ssh->cfg = *cfg; /* STRUCTURE COPY */
6501}
6502
6503/*
374330e2 6504 * Called to send data down the Telnet connection.
6505 */
51470298 6506static int ssh_send(void *handle, char *buf, int len)
32874aea 6507{
51470298 6508 Ssh ssh = (Ssh) handle;
6509
6510 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
5471d09a 6511 return 0;
374330e2 6512
d8baa528 6513 ssh->protocol(ssh, (unsigned char *)buf, len, 0);
5471d09a 6514
51470298 6515 return ssh_sendbuffer(ssh);
5471d09a 6516}
6517
6518/*
6519 * Called to query the current amount of buffered stdin data.
6520 */
51470298 6521static int ssh_sendbuffer(void *handle)
5471d09a 6522{
51470298 6523 Ssh ssh = (Ssh) handle;
5471d09a 6524 int override_value;
6525
51470298 6526 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
5471d09a 6527 return 0;
6528
6529 /*
6530 * If the SSH socket itself has backed up, add the total backup
6531 * size on that to any individual buffer on the stdin channel.
6532 */
6533 override_value = 0;
51470298 6534 if (ssh->throttled_all)
6535 override_value = ssh->overall_bufsize;
5471d09a 6536
51470298 6537 if (ssh->version == 1) {
5471d09a 6538 return override_value;
51470298 6539 } else if (ssh->version == 2) {
6540 if (!ssh->mainchan || ssh->mainchan->closes > 0)
5471d09a 6541 return override_value;
6542 else
51470298 6543 return (override_value +
6544 bufchain_size(&ssh->mainchan->v.v2.outbuffer));
5471d09a 6545 }
6546
6547 return 0;
374330e2 6548}
6549
6550/*
6e48c3fe 6551 * Called to set the size of the window from SSH's POV.
374330e2 6552 */
51470298 6553static void ssh_size(void *handle, int width, int height)
32874aea 6554{
51470298 6555 Ssh ssh = (Ssh) handle;
6556
6557 ssh->term_width = width;
6558 ssh->term_height = height;
f278d6f8 6559
51470298 6560 switch (ssh->state) {
374330e2 6561 case SSH_STATE_BEFORE_SIZE:
3687d221 6562 case SSH_STATE_PREPACKET:
21248260 6563 case SSH_STATE_CLOSED:
374330e2 6564 break; /* do nothing */
6565 case SSH_STATE_INTERMED:
51470298 6566 ssh->size_needed = TRUE; /* buffer for later */
374330e2 6567 break;
6568 case SSH_STATE_SESSION:
86916870 6569 if (!ssh->cfg.nopty) {
51470298 6570 if (ssh->version == 1) {
6571 send_packet(ssh, SSH1_CMSG_WINDOW_SIZE,
6572 PKT_INT, ssh->term_height,
6573 PKT_INT, ssh->term_width,
32874aea 6574 PKT_INT, 0, PKT_INT, 0, PKT_END);
6575 } else {
51470298 6576 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
6577 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
6578 ssh2_pkt_addstring(ssh, "window-change");
6579 ssh2_pkt_addbool(ssh, 0);
6580 ssh2_pkt_adduint32(ssh, ssh->term_width);
6581 ssh2_pkt_adduint32(ssh, ssh->term_height);
6582 ssh2_pkt_adduint32(ssh, 0);
6583 ssh2_pkt_adduint32(ssh, 0);
6584 ssh2_pkt_send(ssh);
32874aea 6585 }
6586 }
6587 break;
374330e2 6588 }
6589}
6590
6591/*
125105d1 6592 * Return a list of the special codes that make sense in this
6593 * protocol.
6594 */
6595static const struct telnet_special *ssh_get_specials(void *handle)
6596{
6597 Ssh ssh = (Ssh) handle;
6598
6599 if (ssh->version == 1) {
6600 static const struct telnet_special ssh1_specials[] = {
6601 {"IGNORE message", TS_NOP},
6602 {NULL, 0}
6603 };
6604 return ssh1_specials;
6605 } else if (ssh->version == 2) {
6606 static const struct telnet_special ssh2_specials[] = {
6607 {"Break", TS_BRK},
6608 {"IGNORE message", TS_NOP},
6609 {NULL, 0}
6610 };
6611 return ssh2_specials;
6612 } else
6613 return NULL;
6614}
6615
6616/*
6abbf9e3 6617 * Send Telnet special codes. TS_EOF is useful for `plink', so you
6618 * can send an EOF and collect resulting output (e.g. `plink
6619 * hostname sort').
374330e2 6620 */
51470298 6621static void ssh_special(void *handle, Telnet_Special code)
32874aea 6622{
51470298 6623 Ssh ssh = (Ssh) handle;
6624
6abbf9e3 6625 if (code == TS_EOF) {
51470298 6626 if (ssh->state != SSH_STATE_SESSION) {
32874aea 6627 /*
6628 * Buffer the EOF in case we are pre-SESSION, so we can
6629 * send it as soon as we reach SESSION.
6630 */
6631 if (code == TS_EOF)
51470298 6632 ssh->eof_needed = TRUE;
32874aea 6633 return;
6634 }
51470298 6635 if (ssh->version == 1) {
6636 send_packet(ssh, SSH1_CMSG_EOF, PKT_END);
32874aea 6637 } else {
51470298 6638 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_EOF);
6639 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
6640 ssh2_pkt_send(ssh);
32874aea 6641 }
6642 logevent("Sent EOF message");
125105d1 6643 } else if (code == TS_PING || code == TS_NOP) {
51470298 6644 if (ssh->state == SSH_STATE_CLOSED
6645 || ssh->state == SSH_STATE_PREPACKET) return;
6646 if (ssh->version == 1) {
6647 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE))
6648 send_packet(ssh, SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
32874aea 6649 } else {
51470298 6650 ssh2_pkt_init(ssh, SSH2_MSG_IGNORE);
6651 ssh2_pkt_addstring_start(ssh);
6652 ssh2_pkt_send(ssh);
32874aea 6653 }
125105d1 6654 } else if (code == TS_BRK) {
6655 if (ssh->state == SSH_STATE_CLOSED
6656 || ssh->state == SSH_STATE_PREPACKET) return;
6657 if (ssh->version == 1) {
6658 logevent("Unable to send BREAK signal in SSH1");
6659 } else {
6660 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
6661 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
6662 ssh2_pkt_addstring(ssh, "break");
6663 ssh2_pkt_addbool(ssh, 0);
6664 ssh2_pkt_adduint32(ssh, 0); /* default break length */
6665 ssh2_pkt_send(ssh);
6666 }
6abbf9e3 6667 } else {
32874aea 6668 /* do nothing */
6abbf9e3 6669 }
374330e2 6670}
6671
51470298 6672void *new_sock_channel(void *handle, Socket s)
d74d141c 6673{
51470298 6674 Ssh ssh = (Ssh) handle;
d74d141c 6675 struct ssh_channel *c;
3d88e64d 6676 c = snew(struct ssh_channel);
51470298 6677 c->ssh = ssh;
d74d141c 6678
6679 if (c) {
bc240b21 6680 c->remoteid = -1; /* to be set when open confirmed */
51470298 6681 c->localid = alloc_channel_id(ssh);
d74d141c 6682 c->closes = 0;
bc240b21 6683 c->type = CHAN_SOCKDATA_DORMANT;/* identify channel type */
d74d141c 6684 c->u.pfd.s = s;
013dd8c0 6685 bufchain_init(&c->v.v2.outbuffer);
51470298 6686 add234(ssh->channels, c);
d74d141c 6687 }
6688 return c;
6689}
6690
5471d09a 6691/*
6692 * This is called when stdout/stderr (the entity to which
6693 * from_backend sends data) manages to clear some backlog.
6694 */
ae9ae89f 6695static void ssh_unthrottle(void *handle, int bufsize)
5471d09a 6696{
51470298 6697 Ssh ssh = (Ssh) handle;
6698 if (ssh->version == 1) {
6699 if (ssh->v1_stdout_throttling && bufsize < SSH1_BUFFER_LIMIT) {
6700 ssh->v1_stdout_throttling = 0;
6701 ssh1_throttle(ssh, -1);
5471d09a 6702 }
6703 } else {
51470298 6704 if (ssh->mainchan && ssh->mainchan->closes == 0)
6705 ssh2_set_window(ssh->mainchan, OUR_V2_WINSIZE - bufsize);
5471d09a 6706 }
6707}
6708
6b78788a 6709void ssh_send_port_open(void *channel, char *hostname, int port, char *org)
d74d141c 6710{
6711 struct ssh_channel *c = (struct ssh_channel *)channel;
6b78788a 6712 Ssh ssh = c->ssh;
d74d141c 6713
57356d63 6714 logeventf(ssh, "Opening forwarded connection to %s:%d", hostname, port);
d74d141c 6715
51470298 6716 if (ssh->version == 1) {
6717 send_packet(ssh, SSH1_MSG_PORT_OPEN,
bc240b21 6718 PKT_INT, c->localid,
6719 PKT_STR, hostname,
6720 PKT_INT, port,
6721 //PKT_STR, <org:orgport>,
6722 PKT_END);
6723 } else {
51470298 6724 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_OPEN);
6725 ssh2_pkt_addstring(ssh, "direct-tcpip");
6726 ssh2_pkt_adduint32(ssh, c->localid);
5471d09a 6727 c->v.v2.locwindow = OUR_V2_WINSIZE;
51470298 6728 ssh2_pkt_adduint32(ssh, c->v.v2.locwindow);/* our window size */
6729 ssh2_pkt_adduint32(ssh, 0x4000UL); /* our max pkt size */
6730 ssh2_pkt_addstring(ssh, hostname);
6731 ssh2_pkt_adduint32(ssh, port);
bc240b21 6732 /*
6733 * We make up values for the originator data; partly it's
6734 * too much hassle to keep track, and partly I'm not
6735 * convinced the server should be told details like that
6736 * about my local network configuration.
6737 */
51470298 6738 ssh2_pkt_addstring(ssh, "client-side-connection");
6739 ssh2_pkt_adduint32(ssh, 0);
6740 ssh2_pkt_send(ssh);
bc240b21 6741 }
d74d141c 6742}
6743
6744
51470298 6745static Socket ssh_socket(void *handle)
32874aea 6746{
51470298 6747 Ssh ssh = (Ssh) handle;
6748 return ssh->s;
32874aea 6749}
8ccc75b0 6750
51470298 6751static int ssh_sendok(void *handle)
32874aea 6752{
51470298 6753 Ssh ssh = (Ssh) handle;
6754 return ssh->send_ok;
32874aea 6755}
fb09bf1c 6756
51470298 6757static int ssh_ldisc(void *handle, int option)
32874aea 6758{
51470298 6759 Ssh ssh = (Ssh) handle;
32874aea 6760 if (option == LD_ECHO)
51470298 6761 return ssh->echoing;
32874aea 6762 if (option == LD_EDIT)
51470298 6763 return ssh->editing;
0965bee0 6764 return FALSE;
6765}
6766
b9d7bcad 6767static void ssh_provide_ldisc(void *handle, void *ldisc)
6768{
6769 Ssh ssh = (Ssh) handle;
6770 ssh->ldisc = ldisc;
6771}
6772
a8327734 6773static void ssh_provide_logctx(void *handle, void *logctx)
6774{
6775 Ssh ssh = (Ssh) handle;
6776 ssh->logctx = logctx;
6777}
6778
51470298 6779static int ssh_return_exitcode(void *handle)
6780{
6781 Ssh ssh = (Ssh) handle;
3bb2f322 6782 if (ssh->s != NULL)
6783 return -1;
6784 else
6785 return (ssh->exitcode >= 0 ? ssh->exitcode : 0);
51470298 6786}
6787
6788/*
6789 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
6790 * that fails. This variable is the means by which scp.c can reach
6791 * into the SSH code and find out which one it got.
6792 */
6793extern int ssh_fallback_cmd(void *handle)
d8d6c7e5 6794{
51470298 6795 Ssh ssh = (Ssh) handle;
6796 return ssh->fallback_cmd;
d8d6c7e5 6797}
6798
374330e2 6799Backend ssh_backend = {
6800 ssh_init,
fabd1805 6801 ssh_free,
86916870 6802 ssh_reconfig,
374330e2 6803 ssh_send,
5471d09a 6804 ssh_sendbuffer,
374330e2 6805 ssh_size,
4017be6d 6806 ssh_special,
125105d1 6807 ssh_get_specials,
8ccc75b0 6808 ssh_socket,
d8d6c7e5 6809 ssh_return_exitcode,
97db3be4 6810 ssh_sendok,
0965bee0 6811 ssh_ldisc,
b9d7bcad 6812 ssh_provide_ldisc,
a8327734 6813 ssh_provide_logctx,
5471d09a 6814 ssh_unthrottle,
97db3be4 6815 22
bc240b21 6816};
Local modifications for Simon Tatham's `PuTTY' SSH client and terminal emulator