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Mention the negotiated SSH-2 MAC algorithm(s) in the Event Log.
[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
ae0500e5 830 if (st->biglen < 0) {
831 bombout(("Extremely large packet length from server suggests"
832 " data stream corruption"));
833 crStop(0);
834 }
835
51470298 836 if (ssh->pktin.maxlen < st->biglen) {
837 ssh->pktin.maxlen = st->biglen;
3d88e64d 838 ssh->pktin.data = sresize(ssh->pktin.data, st->biglen + APIEXTRA,
839 unsigned char);
fb09bf1c 840 }
374330e2 841
57476f6b 842 st->to_read = st->biglen;
51470298 843 st->p = ssh->pktin.data;
57476f6b 844 while (st->to_read > 0) {
32874aea 845 st->chunk = st->to_read;
fb09bf1c 846 while ((*datalen) == 0)
57476f6b 847 crReturn(st->to_read);
848 if (st->chunk > (*datalen))
849 st->chunk = (*datalen);
850 memcpy(st->p, *data, st->chunk);
851 *data += st->chunk;
852 *datalen -= st->chunk;
853 st->p += st->chunk;
854 st->to_read -= st->chunk;
fb09bf1c 855 }
374330e2 856
0183b242 857 if (ssh->cipher && detect_attack(ssh->crcda_ctx, ssh->pktin.data,
858 st->biglen, NULL)) {
6b5cf8b4 859 bombout(("Network attack (CRC compensation) detected!"));
7ffdbc1a 860 crStop(0);
9a3a93a5 861 }
862
51470298 863 if (ssh->cipher)
371e569c 864 ssh->cipher->decrypt(ssh->v1_cipher_ctx, ssh->pktin.data, st->biglen);
374330e2 865
71bedafe 866 st->realcrc = crc32_compute(ssh->pktin.data, st->biglen - 4);
51470298 867 st->gotcrc = GET_32BIT(ssh->pktin.data + st->biglen - 4);
57476f6b 868 if (st->gotcrc != st->realcrc) {
6b5cf8b4 869 bombout(("Incorrect CRC received on packet"));
7ffdbc1a 870 crStop(0);
fb09bf1c 871 }
572f871e 872
51470298 873 ssh->pktin.body = ssh->pktin.data + st->pad + 1;
0016d70b 874 ssh->pktin.savedpos = 0;
4ba9b64b 875
51470298 876 if (ssh->v1_compressing) {
4ba9b64b 877 unsigned char *decompblk;
878 int decomplen;
36b8d9bb 879 if (!zlib_decompress_block(ssh->sc_comp_ctx,
880 ssh->pktin.body - 1, ssh->pktin.length + 1,
881 &decompblk, &decomplen)) {
882 bombout(("Zlib decompression encountered invalid data"));
883 crStop(0);
884 }
4ba9b64b 885
51470298 886 if (ssh->pktin.maxlen < st->pad + decomplen) {
887 ssh->pktin.maxlen = st->pad + decomplen;
3d88e64d 888 ssh->pktin.data = sresize(ssh->pktin.data,
889 ssh->pktin.maxlen + APIEXTRA,
890 unsigned char);
51470298 891 ssh->pktin.body = ssh->pktin.data + st->pad + 1;
4ba9b64b 892 }
893
51470298 894 memcpy(ssh->pktin.body - 1, decompblk, decomplen);
dcbde236 895 sfree(decompblk);
51470298 896 ssh->pktin.length = decomplen - 1;
4ba9b64b 897 }
898
51470298 899 ssh->pktin.type = ssh->pktin.body[-1];
00db133f 900
a8327734 901 if (ssh->logctx)
902 log_packet(ssh->logctx,
903 PKT_INCOMING, ssh->pktin.type,
904 ssh1_pkt_type(ssh->pktin.type),
905 ssh->pktin.body, ssh->pktin.length);
00db133f 906
51470298 907 if (ssh->pktin.type == SSH1_SMSG_STDOUT_DATA ||
908 ssh->pktin.type == SSH1_SMSG_STDERR_DATA ||
909 ssh->pktin.type == SSH1_MSG_DEBUG ||
910 ssh->pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE ||
911 ssh->pktin.type == SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
912 long stringlen = GET_32BIT(ssh->pktin.body);
913 if (stringlen + 4 != ssh->pktin.length) {
6b5cf8b4 914 bombout(("Received data packet with bogus string length"));
7ffdbc1a 915 crStop(0);
32874aea 916 }
fb09bf1c 917 }
918
51470298 919 if (ssh->pktin.type == SSH1_MSG_DEBUG) {
fb09bf1c 920 /* log debug message */
eb4504cc 921 char buf[512];
51470298 922 int stringlen = GET_32BIT(ssh->pktin.body);
eb4504cc 923 strcpy(buf, "Remote debug message: ");
924 if (stringlen > 480)
925 stringlen = 480;
51470298 926 memcpy(buf + 8, ssh->pktin.body + 4, stringlen);
3d63ca2e 927 buf[8 + stringlen] = '\0';
fb09bf1c 928 logevent(buf);
929 goto next_packet;
51470298 930 } else if (ssh->pktin.type == SSH1_MSG_IGNORE) {
fb09bf1c 931 /* do nothing */
932 goto next_packet;
933 }
934
51470298 935 if (ssh->pktin.type == SSH1_MSG_DISCONNECT) {
38c4a8da 936 /* log reason code in disconnect message */
937 char buf[256];
51470298 938 unsigned msglen = GET_32BIT(ssh->pktin.body);
260f3dec 939 unsigned nowlen;
38c4a8da 940 strcpy(buf, "Remote sent disconnect: ");
941 nowlen = strlen(buf);
32874aea 942 if (msglen > sizeof(buf) - nowlen - 1)
943 msglen = sizeof(buf) - nowlen - 1;
51470298 944 memcpy(buf + nowlen, ssh->pktin.body + 4, msglen);
32874aea 945 buf[nowlen + msglen] = '\0';
247308b5 946 /* logevent(buf); (this is now done within the bombout macro) */
6b5cf8b4 947 bombout(("Server sent disconnect message:\n\"%s\"", buf+nowlen));
7ffdbc1a 948 crStop(0);
38c4a8da 949 }
950
fb09bf1c 951 crFinish(0);
952}
953
51470298 954static int ssh2_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
e5574168 955{
51470298 956 struct rdpkt2_state_tag *st = &ssh->rdpkt2_state;
e5574168 957
51470298 958 crBegin(ssh->ssh2_rdpkt_crstate);
e5574168 959
32874aea 960 next_packet:
51470298 961 ssh->pktin.type = 0;
962 ssh->pktin.length = 0;
963 if (ssh->sccipher)
964 st->cipherblk = ssh->sccipher->blksize;
e5574168 965 else
32874aea 966 st->cipherblk = 8;
960e736a 967 if (st->cipherblk < 8)
32874aea 968 st->cipherblk = 8;
960e736a 969
51470298 970 if (ssh->pktin.maxlen < st->cipherblk) {
971 ssh->pktin.maxlen = st->cipherblk;
3d88e64d 972 ssh->pktin.data = sresize(ssh->pktin.data, st->cipherblk + APIEXTRA,
973 unsigned char);
e5574168 974 }
975
976 /*
977 * Acquire and decrypt the first block of the packet. This will
978 * contain the length and padding details.
979 */
32874aea 980 for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) {
e5574168 981 while ((*datalen) == 0)
32874aea 982 crReturn(st->cipherblk - st->i);
51470298 983 ssh->pktin.data[st->i] = *(*data)++;
32874aea 984 (*datalen)--;
e5574168 985 }
4252c9cc 986
51470298 987 if (ssh->sccipher)
371e569c 988 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
989 ssh->pktin.data, st->cipherblk);
e5574168 990
991 /*
992 * Now get the length and padding figures.
993 */
51470298 994 st->len = GET_32BIT(ssh->pktin.data);
995 st->pad = ssh->pktin.data[4];
e5574168 996
997 /*
717dc483 998 * _Completely_ silly lengths should be stomped on before they
999 * do us any more damage.
1000 */
1001 if (st->len < 0 || st->pad < 0 || st->len + st->pad < 0) {
6b5cf8b4 1002 bombout(("Incoming packet was garbled on decryption"));
7ffdbc1a 1003 crStop(0);
717dc483 1004 }
1005
1006 /*
e5574168 1007 * This enables us to deduce the payload length.
1008 */
960e736a 1009 st->payload = st->len - st->pad - 1;
e5574168 1010
51470298 1011 ssh->pktin.length = st->payload + 5;
e5574168 1012
1013 /*
1014 * So now we can work out the total packet length.
1015 */
960e736a 1016 st->packetlen = st->len + 4;
51470298 1017 st->maclen = ssh->scmac ? ssh->scmac->len : 0;
e5574168 1018
1019 /*
1020 * Adjust memory allocation if packet is too big.
1021 */
51470298 1022 if (ssh->pktin.maxlen < st->packetlen + st->maclen) {
1023 ssh->pktin.maxlen = st->packetlen + st->maclen;
3d88e64d 1024 ssh->pktin.data = sresize(ssh->pktin.data,
1025 ssh->pktin.maxlen + APIEXTRA,
1026 unsigned char);
e5574168 1027 }
1028
1029 /*
1030 * Read and decrypt the remainder of the packet.
1031 */
32874aea 1032 for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen;
1033 st->i++) {
e5574168 1034 while ((*datalen) == 0)
960e736a 1035 crReturn(st->packetlen + st->maclen - st->i);
51470298 1036 ssh->pktin.data[st->i] = *(*data)++;
32874aea 1037 (*datalen)--;
e5574168 1038 }
1039 /* Decrypt everything _except_ the MAC. */
51470298 1040 if (ssh->sccipher)
371e569c 1041 ssh->sccipher->decrypt(ssh->sc_cipher_ctx,
1042 ssh->pktin.data + st->cipherblk,
51470298 1043 st->packetlen - st->cipherblk);
e5574168 1044
1045 /*
1046 * Check the MAC.
1047 */
51470298 1048 if (ssh->scmac
e0e1a00d 1049 && !ssh->scmac->verify(ssh->sc_mac_ctx, ssh->pktin.data, st->len + 4,
51470298 1050 st->incoming_sequence)) {
6b5cf8b4 1051 bombout(("Incorrect MAC received on packet"));
7ffdbc1a 1052 crStop(0);
8d5de777 1053 }
32874aea 1054 st->incoming_sequence++; /* whether or not we MACed */
e5574168 1055
4ba9b64b 1056 /*
1057 * Decompress packet payload.
1058 */
1059 {
1060 unsigned char *newpayload;
1061 int newlen;
51470298 1062 if (ssh->sccomp &&
5366aed8 1063 ssh->sccomp->decompress(ssh->sc_comp_ctx,
1064 ssh->pktin.data + 5, ssh->pktin.length - 5,
51470298 1065 &newpayload, &newlen)) {
1066 if (ssh->pktin.maxlen < newlen + 5) {
1067 ssh->pktin.maxlen = newlen + 5;
3d88e64d 1068 ssh->pktin.data = sresize(ssh->pktin.data,
1069 ssh->pktin.maxlen + APIEXTRA,
1070 unsigned char);
4ba9b64b 1071 }
51470298 1072 ssh->pktin.length = 5 + newlen;
1073 memcpy(ssh->pktin.data + 5, newpayload, newlen);
dcbde236 1074 sfree(newpayload);
4ba9b64b 1075 }
1076 }
1077
51470298 1078 ssh->pktin.savedpos = 6;
0016d70b 1079 ssh->pktin.body = ssh->pktin.data;
51470298 1080 ssh->pktin.type = ssh->pktin.data[5];
e5574168 1081
a8327734 1082 if (ssh->logctx)
1083 log_packet(ssh->logctx, PKT_INCOMING, ssh->pktin.type,
1084 ssh2_pkt_type(ssh->pkt_ctx, ssh->pktin.type),
1085 ssh->pktin.data+6, ssh->pktin.length-6);
00db133f 1086
51470298 1087 switch (ssh->pktin.type) {
3d63ca2e 1088 /*
1089 * These packets we must handle instantly.
1090 */
1091 case SSH2_MSG_DISCONNECT:
1092 {
1093 /* log reason code in disconnect message */
57356d63 1094 char *buf;
1095 int nowlen;
51470298 1096 int reason = GET_32BIT(ssh->pktin.data + 6);
1097 unsigned msglen = GET_32BIT(ssh->pktin.data + 10);
57356d63 1098
3d63ca2e 1099 if (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) {
57356d63 1100 buf = dupprintf("Received disconnect message (%s)",
1101 ssh2_disconnect_reasons[reason]);
3d63ca2e 1102 } else {
57356d63 1103 buf = dupprintf("Received disconnect message (unknown"
1104 " type %d)", reason);
3d63ca2e 1105 }
1106 logevent(buf);
57356d63 1107 sfree(buf);
1108 buf = dupprintf("Disconnection message text: %n%.*s",
33b82b22 1109 &nowlen, msglen, ssh->pktin.data + 14);
3d63ca2e 1110 logevent(buf);
6b5cf8b4 1111 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
3d63ca2e 1112 reason,
1113 (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) ?
1114 ssh2_disconnect_reasons[reason] : "unknown",
1115 buf+nowlen));
57356d63 1116 sfree(buf);
7ffdbc1a 1117 crStop(0);
3d63ca2e 1118 }
1119 break;
1120 case SSH2_MSG_IGNORE:
1121 goto next_packet;
1122 case SSH2_MSG_DEBUG:
1123 {
1124 /* log the debug message */
1125 char buf[512];
51470298 1126 /* int display = ssh->pktin.body[6]; */
1127 int stringlen = GET_32BIT(ssh->pktin.data+7);
3d63ca2e 1128 int prefix;
1129 strcpy(buf, "Remote debug message: ");
1130 prefix = strlen(buf);
51470298 1131 if (stringlen > (int)(sizeof(buf)-prefix-1))
3d63ca2e 1132 stringlen = sizeof(buf)-prefix-1;
51470298 1133 memcpy(buf + prefix, ssh->pktin.data + 11, stringlen);
3d63ca2e 1134 buf[prefix + stringlen] = '\0';
1135 logevent(buf);
38c4a8da 1136 }
3d63ca2e 1137 goto next_packet; /* FIXME: print the debug message */
1138
1139 /*
1140 * These packets we need do nothing about here.
1141 */
1142 case SSH2_MSG_UNIMPLEMENTED:
1143 case SSH2_MSG_SERVICE_REQUEST:
1144 case SSH2_MSG_SERVICE_ACCEPT:
1145 case SSH2_MSG_KEXINIT:
1146 case SSH2_MSG_NEWKEYS:
1147 case SSH2_MSG_KEXDH_INIT:
1148 case SSH2_MSG_KEXDH_REPLY:
1149 /* case SSH2_MSG_KEX_DH_GEX_REQUEST: duplicate case value */
1150 /* case SSH2_MSG_KEX_DH_GEX_GROUP: duplicate case value */
1151 case SSH2_MSG_KEX_DH_GEX_INIT:
1152 case SSH2_MSG_KEX_DH_GEX_REPLY:
1153 case SSH2_MSG_USERAUTH_REQUEST:
1154 case SSH2_MSG_USERAUTH_FAILURE:
1155 case SSH2_MSG_USERAUTH_SUCCESS:
1156 case SSH2_MSG_USERAUTH_BANNER:
1157 case SSH2_MSG_USERAUTH_PK_OK:
1158 /* case SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: duplicate case value */
1159 /* case SSH2_MSG_USERAUTH_INFO_REQUEST: duplicate case value */
1160 case SSH2_MSG_USERAUTH_INFO_RESPONSE:
1161 case SSH2_MSG_GLOBAL_REQUEST:
1162 case SSH2_MSG_REQUEST_SUCCESS:
1163 case SSH2_MSG_REQUEST_FAILURE:
1164 case SSH2_MSG_CHANNEL_OPEN:
1165 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
1166 case SSH2_MSG_CHANNEL_OPEN_FAILURE:
1167 case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
1168 case SSH2_MSG_CHANNEL_DATA:
1169 case SSH2_MSG_CHANNEL_EXTENDED_DATA:
1170 case SSH2_MSG_CHANNEL_EOF:
1171 case SSH2_MSG_CHANNEL_CLOSE:
1172 case SSH2_MSG_CHANNEL_REQUEST:
1173 case SSH2_MSG_CHANNEL_SUCCESS:
1174 case SSH2_MSG_CHANNEL_FAILURE:
1175 break;
1176
1177 /*
1178 * For anything else we send SSH2_MSG_UNIMPLEMENTED.
1179 */
1180 default:
51470298 1181 ssh2_pkt_init(ssh, SSH2_MSG_UNIMPLEMENTED);
1182 ssh2_pkt_adduint32(ssh, st->incoming_sequence - 1);
1183 ssh2_pkt_send(ssh);
3d63ca2e 1184 break;
38c4a8da 1185 }
1186
e5574168 1187 crFinish(0);
1188}
1189
51470298 1190static void ssh1_pktout_size(Ssh ssh, int len)
32874aea 1191{
374330e2 1192 int pad, biglen;
1193
1194 len += 5; /* type and CRC */
32874aea 1195 pad = 8 - (len % 8);
374330e2 1196 biglen = len + pad;
1197
51470298 1198 ssh->pktout.length = len - 5;
1199 if (ssh->pktout.maxlen < biglen) {
1200 ssh->pktout.maxlen = biglen;
8f203108 1201#ifdef MSCRYPTOAPI
fb09bf1c 1202 /* Allocate enough buffer space for extra block
8f203108 1203 * for MS CryptEncrypt() */
3d88e64d 1204 ssh->pktout.data = sresize(ssh->pktout.data, biglen + 12,
1205 unsigned char);
8f203108 1206#else
3d88e64d 1207 ssh->pktout.data = sresize(ssh->pktout.data, biglen + 4,
1208 unsigned char);
8f203108 1209#endif
374330e2 1210 }
51470298 1211 ssh->pktout.body = ssh->pktout.data + 4 + pad + 1;
4ba9b64b 1212}
374330e2 1213
51470298 1214static void s_wrpkt_start(Ssh ssh, int type, int len)
32874aea 1215{
51470298 1216 ssh1_pktout_size(ssh, len);
1217 ssh->pktout.type = type;
374330e2 1218}
1219
51470298 1220static int s_wrpkt_prepare(Ssh ssh)
32874aea 1221{
fd7a4aad 1222 int pad, biglen, i;
374330e2 1223 unsigned long crc;
fd7a4aad 1224#ifdef __SC__
1225 /*
1226 * XXX various versions of SC (including 8.8.4) screw up the
1227 * register allocation in this function and use the same register
1228 * (D6) for len and as a temporary, with predictable results. The
1229 * following sledgehammer prevents this.
1230 */
1231 volatile
1232#endif
1233 int len;
374330e2 1234
51470298 1235 ssh->pktout.body[-1] = ssh->pktout.type;
4ba9b64b 1236
a8327734 1237 if (ssh->logctx)
1238 log_packet(ssh->logctx, PKT_OUTGOING, ssh->pktout.type,
1239 ssh1_pkt_type(ssh->pktout.type),
1240 ssh->pktout.body, ssh->pktout.length);
00db133f 1241
51470298 1242 if (ssh->v1_compressing) {
4ba9b64b 1243 unsigned char *compblk;
1244 int complen;
5366aed8 1245 zlib_compress_block(ssh->cs_comp_ctx,
1246 ssh->pktout.body - 1, ssh->pktout.length + 1,
4ba9b64b 1247 &compblk, &complen);
51470298 1248 ssh1_pktout_size(ssh, complen - 1);
1249 memcpy(ssh->pktout.body - 1, compblk, complen);
dcbde236 1250 sfree(compblk);
4ba9b64b 1251 }
1252
51470298 1253 len = ssh->pktout.length + 5; /* type and CRC */
32874aea 1254 pad = 8 - (len % 8);
374330e2 1255 biglen = len + pad;
1256
32874aea 1257 for (i = 0; i < pad; i++)
51470298 1258 ssh->pktout.data[i + 4] = random_byte();
71bedafe 1259 crc = crc32_compute(ssh->pktout.data + 4, biglen - 4);
51470298 1260 PUT_32BIT(ssh->pktout.data + biglen, crc);
1261 PUT_32BIT(ssh->pktout.data, len);
374330e2 1262
51470298 1263 if (ssh->cipher)
371e569c 1264 ssh->cipher->encrypt(ssh->v1_cipher_ctx, ssh->pktout.data + 4, biglen);
374330e2 1265
32874aea 1266 return biglen + 4;
39065bed 1267}
1268
51470298 1269static void s_wrpkt(Ssh ssh)
32874aea 1270{
5471d09a 1271 int len, backlog;
51470298 1272 len = s_wrpkt_prepare(ssh);
d8baa528 1273 backlog = sk_write(ssh->s, (char *)ssh->pktout.data, len);
5471d09a 1274 if (backlog > SSH_MAX_BACKLOG)
51470298 1275 ssh_throttle_all(ssh, 1, backlog);
39065bed 1276}
1277
51470298 1278static void s_wrpkt_defer(Ssh ssh)
32874aea 1279{
39065bed 1280 int len;
51470298 1281 len = s_wrpkt_prepare(ssh);
1282 if (ssh->deferred_len + len > ssh->deferred_size) {
1283 ssh->deferred_size = ssh->deferred_len + len + 128;
3d88e64d 1284 ssh->deferred_send_data = sresize(ssh->deferred_send_data,
1285 ssh->deferred_size,
1286 unsigned char);
39065bed 1287 }
51470298 1288 memcpy(ssh->deferred_send_data + ssh->deferred_len, ssh->pktout.data, len);
1289 ssh->deferred_len += len;
374330e2 1290}
1291
fb09bf1c 1292/*
39065bed 1293 * Construct a packet with the specified contents.
fb09bf1c 1294 */
51470298 1295static void construct_packet(Ssh ssh, int pkttype, va_list ap1, va_list ap2)
fb09bf1c 1296{
fb09bf1c 1297 unsigned char *p, *argp, argchar;
1298 unsigned long argint;
1299 int pktlen, argtype, arglen;
7cca0d81 1300 Bignum bn;
fb09bf1c 1301
1302 pktlen = 0;
39065bed 1303 while ((argtype = va_arg(ap1, int)) != PKT_END) {
fb09bf1c 1304 switch (argtype) {
1305 case PKT_INT:
39065bed 1306 (void) va_arg(ap1, int);
fb09bf1c 1307 pktlen += 4;
1308 break;
1309 case PKT_CHAR:
1ec39246 1310 (void) va_arg(ap1, int);
fb09bf1c 1311 pktlen++;
1312 break;
1313 case PKT_DATA:
39065bed 1314 (void) va_arg(ap1, unsigned char *);
1315 arglen = va_arg(ap1, int);
fb09bf1c 1316 pktlen += arglen;
1317 break;
1318 case PKT_STR:
39065bed 1319 argp = va_arg(ap1, unsigned char *);
d8baa528 1320 arglen = strlen((char *)argp);
fb09bf1c 1321 pktlen += 4 + arglen;
1322 break;
7cca0d81 1323 case PKT_BIGNUM:
39065bed 1324 bn = va_arg(ap1, Bignum);
32874aea 1325 pktlen += ssh1_bignum_length(bn);
7cca0d81 1326 break;
fb09bf1c 1327 default:
1328 assert(0);
1329 }
1330 }
fb09bf1c 1331
51470298 1332 s_wrpkt_start(ssh, pkttype, pktlen);
1333 p = ssh->pktout.body;
fb09bf1c 1334
39065bed 1335 while ((argtype = va_arg(ap2, int)) != PKT_END) {
fb09bf1c 1336 switch (argtype) {
1337 case PKT_INT:
39065bed 1338 argint = va_arg(ap2, int);
fb09bf1c 1339 PUT_32BIT(p, argint);
1340 p += 4;
1341 break;
1342 case PKT_CHAR:
1ec39246 1343 argchar = (unsigned char) va_arg(ap2, int);
fb09bf1c 1344 *p = argchar;
1345 p++;
1346 break;
1347 case PKT_DATA:
39065bed 1348 argp = va_arg(ap2, unsigned char *);
1349 arglen = va_arg(ap2, int);
fb09bf1c 1350 memcpy(p, argp, arglen);
1351 p += arglen;
1352 break;
1353 case PKT_STR:
39065bed 1354 argp = va_arg(ap2, unsigned char *);
d8baa528 1355 arglen = strlen((char *)argp);
fb09bf1c 1356 PUT_32BIT(p, arglen);
1357 memcpy(p + 4, argp, arglen);
1358 p += 4 + arglen;
1359 break;
7cca0d81 1360 case PKT_BIGNUM:
39065bed 1361 bn = va_arg(ap2, Bignum);
32874aea 1362 p += ssh1_write_bignum(p, bn);
7cca0d81 1363 break;
fb09bf1c 1364 }
1365 }
39065bed 1366}
fb09bf1c 1367
51470298 1368static void send_packet(Ssh ssh, int pkttype, ...)
32874aea 1369{
39065bed 1370 va_list ap1, ap2;
1371 va_start(ap1, pkttype);
1372 va_start(ap2, pkttype);
51470298 1373 construct_packet(ssh, pkttype, ap1, ap2);
1374 s_wrpkt(ssh);
fb09bf1c 1375}
1376
51470298 1377static void defer_packet(Ssh ssh, int pkttype, ...)
32874aea 1378{
39065bed 1379 va_list ap1, ap2;
1380 va_start(ap1, pkttype);
1381 va_start(ap2, pkttype);
51470298 1382 construct_packet(ssh, pkttype, ap1, ap2);
1383 s_wrpkt_defer(ssh);
39065bed 1384}
1385
32874aea 1386static int ssh_versioncmp(char *a, char *b)
1387{
9697bfd2 1388 char *ae, *be;
1389 unsigned long av, bv;
1390
43aa02a7 1391 av = strtoul(a, &ae, 10);
1392 bv = strtoul(b, &be, 10);
32874aea 1393 if (av != bv)
1394 return (av < bv ? -1 : +1);
1395 if (*ae == '.')
1396 ae++;
1397 if (*be == '.')
1398 be++;
43aa02a7 1399 av = strtoul(ae, &ae, 10);
1400 bv = strtoul(be, &be, 10);
32874aea 1401 if (av != bv)
1402 return (av < bv ? -1 : +1);
9697bfd2 1403 return 0;
1404}
1405
e5574168 1406/*
a92dd380 1407 * Utility routines for putting an SSH-protocol `string' and
1408 * `uint32' into a SHA state.
e5574168 1409 */
1410#include <stdio.h>
32874aea 1411static void sha_string(SHA_State * s, void *str, int len)
1412{
e5574168 1413 unsigned char lenblk[4];
e5574168 1414 PUT_32BIT(lenblk, len);
e5574168 1415 SHA_Bytes(s, lenblk, 4);
e5574168 1416 SHA_Bytes(s, str, len);
1417}
1418
32874aea 1419static void sha_uint32(SHA_State * s, unsigned i)
1420{
a92dd380 1421 unsigned char intblk[4];
1422 PUT_32BIT(intblk, i);
1423 SHA_Bytes(s, intblk, 4);
1424}
1425
7cca0d81 1426/*
1427 * SSH2 packet construction functions.
1428 */
51470298 1429static void ssh2_pkt_ensure(Ssh ssh, int length)
32874aea 1430{
51470298 1431 if (ssh->pktout.maxlen < length) {
1432 ssh->pktout.maxlen = length + 256;
3d88e64d 1433 ssh->pktout.data = sresize(ssh->pktout.data,
1434 ssh->pktout.maxlen + APIEXTRA,
1435 unsigned char);
51470298 1436 if (!ssh->pktout.data)
32874aea 1437 fatalbox("Out of memory");
7cca0d81 1438 }
783415f8 1439}
51470298 1440static void ssh2_pkt_adddata(Ssh ssh, void *data, int len)
32874aea 1441{
51470298 1442 ssh->pktout.length += len;
1443 ssh2_pkt_ensure(ssh, ssh->pktout.length);
1444 memcpy(ssh->pktout.data + ssh->pktout.length - len, data, len);
7cca0d81 1445}
51470298 1446static void ssh2_pkt_addbyte(Ssh ssh, unsigned char byte)
32874aea 1447{
51470298 1448 ssh2_pkt_adddata(ssh, &byte, 1);
7cca0d81 1449}
51470298 1450static void ssh2_pkt_init(Ssh ssh, int pkt_type)
32874aea 1451{
51470298 1452 ssh->pktout.length = 5;
1453 ssh2_pkt_addbyte(ssh, (unsigned char) pkt_type);
7cca0d81 1454}
51470298 1455static void ssh2_pkt_addbool(Ssh ssh, unsigned char value)
32874aea 1456{
51470298 1457 ssh2_pkt_adddata(ssh, &value, 1);
7cca0d81 1458}
51470298 1459static void ssh2_pkt_adduint32(Ssh ssh, unsigned long value)
32874aea 1460{
7cca0d81 1461 unsigned char x[4];
1462 PUT_32BIT(x, value);
51470298 1463 ssh2_pkt_adddata(ssh, x, 4);
7cca0d81 1464}
51470298 1465static void ssh2_pkt_addstring_start(Ssh ssh)
32874aea 1466{
51470298 1467 ssh2_pkt_adduint32(ssh, 0);
1468 ssh->pktout.savedpos = ssh->pktout.length;
7cca0d81 1469}
51470298 1470static void ssh2_pkt_addstring_str(Ssh ssh, char *data)
32874aea 1471{
51470298 1472 ssh2_pkt_adddata(ssh, data, strlen(data));
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_data(Ssh ssh, char *data, int len)
32874aea 1477{
51470298 1478 ssh2_pkt_adddata(ssh, data, len);
1479 PUT_32BIT(ssh->pktout.data + ssh->pktout.savedpos - 4,
1480 ssh->pktout.length - ssh->pktout.savedpos);
7cca0d81 1481}
51470298 1482static void ssh2_pkt_addstring(Ssh ssh, char *data)
32874aea 1483{
51470298 1484 ssh2_pkt_addstring_start(ssh);
1485 ssh2_pkt_addstring_str(ssh, data);
7cca0d81 1486}
d8baa528 1487static unsigned char *ssh2_mpint_fmt(Bignum b, int *len)
32874aea 1488{
7cca0d81 1489 unsigned char *p;
32874aea 1490 int i, n = (bignum_bitcount(b) + 7) / 8;
3d88e64d 1491 p = snewn(n + 1, unsigned char);
7cca0d81 1492 if (!p)
32874aea 1493 fatalbox("out of memory");
7cca0d81 1494 p[0] = 0;
3709bfe9 1495 for (i = 1; i <= n; i++)
32874aea 1496 p[i] = bignum_byte(b, n - i);
7cca0d81 1497 i = 0;
32874aea 1498 while (i <= n && p[i] == 0 && (p[i + 1] & 0x80) == 0)
1499 i++;
1500 memmove(p, p + i, n + 1 - i);
1501 *len = n + 1 - i;
7cca0d81 1502 return p;
1503}
51470298 1504static void ssh2_pkt_addmp(Ssh ssh, Bignum b)
32874aea 1505{
7cca0d81 1506 unsigned char *p;
1507 int len;
1508 p = ssh2_mpint_fmt(b, &len);
51470298 1509 ssh2_pkt_addstring_start(ssh);
d8baa528 1510 ssh2_pkt_addstring_data(ssh, (char *)p, len);
dcbde236 1511 sfree(p);
7cca0d81 1512}
b185170a 1513
1514/*
1515 * Construct an SSH2 final-form packet: compress it, encrypt it,
1516 * put the MAC on it. Final packet, ready to be sent, is stored in
51470298 1517 * ssh->pktout.data. Total length is returned.
b185170a 1518 */
51470298 1519static int ssh2_pkt_construct(Ssh ssh)
32874aea 1520{
7cca0d81 1521 int cipherblk, maclen, padding, i;
7cca0d81 1522
a8327734 1523 if (ssh->logctx)
1524 log_packet(ssh->logctx, PKT_OUTGOING, ssh->pktout.data[5],
1525 ssh2_pkt_type(ssh->pkt_ctx, ssh->pktout.data[5]),
1526 ssh->pktout.data + 6, ssh->pktout.length - 6);
00db133f 1527
7cca0d81 1528 /*
4ba9b64b 1529 * Compress packet payload.
1530 */
4ba9b64b 1531 {
1532 unsigned char *newpayload;
1533 int newlen;
51470298 1534 if (ssh->cscomp &&
5366aed8 1535 ssh->cscomp->compress(ssh->cs_comp_ctx, ssh->pktout.data + 5,
1536 ssh->pktout.length - 5,
51470298 1537 &newpayload, &newlen)) {
1538 ssh->pktout.length = 5;
1539 ssh2_pkt_adddata(ssh, newpayload, newlen);
dcbde236 1540 sfree(newpayload);
4ba9b64b 1541 }
1542 }
1543
1544 /*
7cca0d81 1545 * Add padding. At least four bytes, and must also bring total
1546 * length (minus MAC) up to a multiple of the block size.
1547 */
51470298 1548 cipherblk = ssh->cscipher ? ssh->cscipher->blksize : 8; /* block size */
32874aea 1549 cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
7cca0d81 1550 padding = 4;
32874aea 1551 padding +=
51470298 1552 (cipherblk - (ssh->pktout.length + padding) % cipherblk) % cipherblk;
1553 maclen = ssh->csmac ? ssh->csmac->len : 0;
1554 ssh2_pkt_ensure(ssh, ssh->pktout.length + padding + maclen);
1555 ssh->pktout.data[4] = padding;
7cca0d81 1556 for (i = 0; i < padding; i++)
51470298 1557 ssh->pktout.data[ssh->pktout.length + i] = random_byte();
1558 PUT_32BIT(ssh->pktout.data, ssh->pktout.length + padding - 4);
1559 if (ssh->csmac)
e0e1a00d 1560 ssh->csmac->generate(ssh->cs_mac_ctx, ssh->pktout.data,
1561 ssh->pktout.length + padding,
51470298 1562 ssh->v2_outgoing_sequence);
1563 ssh->v2_outgoing_sequence++; /* whether or not we MACed */
1564
1565 if (ssh->cscipher)
371e569c 1566 ssh->cscipher->encrypt(ssh->cs_cipher_ctx,
1567 ssh->pktout.data, ssh->pktout.length + padding);
51470298 1568
1569 /* Ready-to-send packet starts at ssh->pktout.data. We return length. */
1570 return ssh->pktout.length + padding + maclen;
b185170a 1571}
1572
1573/*
1574 * Construct and send an SSH2 packet immediately.
1575 */
51470298 1576static void ssh2_pkt_send(Ssh ssh)
32874aea 1577{
5471d09a 1578 int len;
1579 int backlog;
51470298 1580 len = ssh2_pkt_construct(ssh);
d8baa528 1581 backlog = sk_write(ssh->s, (char *)ssh->pktout.data, len);
5471d09a 1582 if (backlog > SSH_MAX_BACKLOG)
51470298 1583 ssh_throttle_all(ssh, 1, backlog);
b185170a 1584}
1585
1586/*
1587 * Construct an SSH2 packet and add it to a deferred data block.
1588 * Useful for sending multiple packets in a single sk_write() call,
1589 * to prevent a traffic-analysing listener from being able to work
1590 * out the length of any particular packet (such as the password
1591 * packet).
1592 *
1593 * Note that because SSH2 sequence-numbers its packets, this can
1594 * NOT be used as an m4-style `defer' allowing packets to be
1595 * constructed in one order and sent in another.
1596 */
51470298 1597static void ssh2_pkt_defer(Ssh ssh)
32874aea 1598{
51470298 1599 int len = ssh2_pkt_construct(ssh);
1600 if (ssh->deferred_len + len > ssh->deferred_size) {
1601 ssh->deferred_size = ssh->deferred_len + len + 128;
3d88e64d 1602 ssh->deferred_send_data = sresize(ssh->deferred_send_data,
1603 ssh->deferred_size,
1604 unsigned char);
b185170a 1605 }
51470298 1606 memcpy(ssh->deferred_send_data + ssh->deferred_len, ssh->pktout.data, len);
1607 ssh->deferred_len += len;
b185170a 1608}
1609
1610/*
1611 * Send the whole deferred data block constructed by
39065bed 1612 * ssh2_pkt_defer() or SSH1's defer_packet().
b185170a 1613 */
51470298 1614static void ssh_pkt_defersend(Ssh ssh)
32874aea 1615{
5471d09a 1616 int backlog;
d8baa528 1617 backlog = sk_write(ssh->s, (char *)ssh->deferred_send_data,
1618 ssh->deferred_len);
51470298 1619 ssh->deferred_len = ssh->deferred_size = 0;
1620 sfree(ssh->deferred_send_data);
1621 ssh->deferred_send_data = NULL;
5471d09a 1622 if (backlog > SSH_MAX_BACKLOG)
51470298 1623 ssh_throttle_all(ssh, 1, backlog);
7cca0d81 1624}
1625
1626#if 0
32874aea 1627void bndebug(char *string, Bignum b)
1628{
7cca0d81 1629 unsigned char *p;
1630 int i, len;
1631 p = ssh2_mpint_fmt(b, &len);
1632 debug(("%s", string));
1633 for (i = 0; i < len; i++)
32874aea 1634 debug((" %02x", p[i]));
765c4200 1635 debug(("\n"));
dcbde236 1636 sfree(p);
7cca0d81 1637}
1638#endif
1639
32874aea 1640static void sha_mpint(SHA_State * s, Bignum b)
1641{
7cca0d81 1642 unsigned char *p;
1643 int len;
1644 p = ssh2_mpint_fmt(b, &len);
1645 sha_string(s, p, len);
dcbde236 1646 sfree(p);
7cca0d81 1647}
1648
1649/*
0016d70b 1650 * Packet decode functions for both SSH1 and SSH2.
7cca0d81 1651 */
0016d70b 1652static unsigned long ssh_pkt_getuint32(Ssh ssh)
32874aea 1653{
7cca0d81 1654 unsigned long value;
51470298 1655 if (ssh->pktin.length - ssh->pktin.savedpos < 4)
32874aea 1656 return 0; /* arrgh, no way to decline (FIXME?) */
0016d70b 1657 value = GET_32BIT(ssh->pktin.body + ssh->pktin.savedpos);
51470298 1658 ssh->pktin.savedpos += 4;
7cca0d81 1659 return value;
1660}
51470298 1661static int ssh2_pkt_getbool(Ssh ssh)
32874aea 1662{
65a22376 1663 unsigned long value;
51470298 1664 if (ssh->pktin.length - ssh->pktin.savedpos < 1)
32874aea 1665 return 0; /* arrgh, no way to decline (FIXME?) */
0016d70b 1666 value = ssh->pktin.body[ssh->pktin.savedpos] != 0;
51470298 1667 ssh->pktin.savedpos++;
65a22376 1668 return value;
1669}
0016d70b 1670static void ssh_pkt_getstring(Ssh ssh, char **p, int *length)
32874aea 1671{
57356d63 1672 int len;
7cca0d81 1673 *p = NULL;
45068b27 1674 *length = 0;
51470298 1675 if (ssh->pktin.length - ssh->pktin.savedpos < 4)
32874aea 1676 return;
0016d70b 1677 len = GET_32BIT(ssh->pktin.body + ssh->pktin.savedpos);
57356d63 1678 if (len < 0)
1679 return;
1680 *length = len;
51470298 1681 ssh->pktin.savedpos += 4;
1682 if (ssh->pktin.length - ssh->pktin.savedpos < *length)
32874aea 1683 return;
0016d70b 1684 *p = (char *)(ssh->pktin.body + ssh->pktin.savedpos);
51470298 1685 ssh->pktin.savedpos += *length;
7cca0d81 1686}
0016d70b 1687static void *ssh_pkt_getdata(Ssh ssh, int length)
1688{
1689 if (ssh->pktin.length - ssh->pktin.savedpos < length)
1690 return NULL;
1691 ssh->pktin.savedpos += length;
1692 return ssh->pktin.body + (ssh->pktin.savedpos - length);
1693}
1694static int ssh1_pkt_getrsakey(Ssh ssh, struct RSAKey *key,
1695 unsigned char **keystr)
1696{
1697 int j;
1698
1699 j = makekey(ssh->pktin.body + ssh->pktin.savedpos,
1700 ssh->pktin.length - ssh->pktin.savedpos,
1701 key, keystr, 0);
1702
1703 if (j < 0)
1704 return FALSE;
1705
1706 ssh->pktin.savedpos += j;
1707 assert(ssh->pktin.savedpos < ssh->pktin.length);
1708
1709 return TRUE;
1710}
1711static Bignum ssh1_pkt_getmp(Ssh ssh)
1712{
1713 int j;
1714 Bignum b;
1715
1716 j = ssh1_read_bignum(ssh->pktin.body + ssh->pktin.savedpos,
1717 ssh->pktin.length - ssh->pktin.savedpos, &b);
1718
1719 if (j < 0)
1720 return NULL;
1721
1722 ssh->pktin.savedpos += j;
1723 return b;
1724}
51470298 1725static Bignum ssh2_pkt_getmp(Ssh ssh)
32874aea 1726{
7cca0d81 1727 char *p;
3709bfe9 1728 int length;
7cca0d81 1729 Bignum b;
1730
0016d70b 1731 ssh_pkt_getstring(ssh, &p, &length);
7cca0d81 1732 if (!p)
32874aea 1733 return NULL;
8d5de777 1734 if (p[0] & 0x80) {
6b5cf8b4 1735 bombout(("internal error: Can't handle negative mpints"));
32874aea 1736 return NULL;
8d5de777 1737 }
d8baa528 1738 b = bignum_from_bytes((unsigned char *)p, length);
7cca0d81 1739 return b;
1740}
1741
7d503c31 1742/*
1dd353b5 1743 * Helper function to add an SSH2 signature blob to a packet.
1744 * Expects to be shown the public key blob as well as the signature
1745 * blob. Normally works just like ssh2_pkt_addstring, but will
1746 * fiddle with the signature packet if necessary for
1747 * BUG_SSH2_RSA_PADDING.
1748 */
51470298 1749static void ssh2_add_sigblob(Ssh ssh, void *pkblob_v, int pkblob_len,
1dd353b5 1750 void *sigblob_v, int sigblob_len)
1751{
1752 unsigned char *pkblob = (unsigned char *)pkblob_v;
1753 unsigned char *sigblob = (unsigned char *)sigblob_v;
1754
1755 /* dmemdump(pkblob, pkblob_len); */
1756 /* dmemdump(sigblob, sigblob_len); */
1757
1758 /*
1759 * See if this is in fact an ssh-rsa signature and a buggy
1760 * server; otherwise we can just do this the easy way.
1761 */
51470298 1762 if ((ssh->remote_bugs & BUG_SSH2_RSA_PADDING) &&
1dd353b5 1763 (GET_32BIT(pkblob) == 7 && !memcmp(pkblob+4, "ssh-rsa", 7))) {
1764 int pos, len, siglen;
1765
1766 /*
1767 * Find the byte length of the modulus.
1768 */
1769
1770 pos = 4+7; /* skip over "ssh-rsa" */
1771 pos += 4 + GET_32BIT(pkblob+pos); /* skip over exponent */
1772 len = GET_32BIT(pkblob+pos); /* find length of modulus */
1773 pos += 4; /* find modulus itself */
1774 while (len > 0 && pkblob[pos] == 0)
1775 len--, pos++;
1776 /* debug(("modulus length is %d\n", len)); */
1777
1778 /*
1779 * Now find the signature integer.
1780 */
1781 pos = 4+7; /* skip over "ssh-rsa" */
1782 siglen = GET_32BIT(sigblob+pos);
1783 /* debug(("signature length is %d\n", siglen)); */
1784
1785 if (len != siglen) {
1786 unsigned char newlen[4];
51470298 1787 ssh2_pkt_addstring_start(ssh);
d8baa528 1788 ssh2_pkt_addstring_data(ssh, (char *)sigblob, pos);
1dd353b5 1789 /* dmemdump(sigblob, pos); */
1790 pos += 4; /* point to start of actual sig */
1791 PUT_32BIT(newlen, len);
d8baa528 1792 ssh2_pkt_addstring_data(ssh, (char *)newlen, 4);
1dd353b5 1793 /* dmemdump(newlen, 4); */
1794 newlen[0] = 0;
1795 while (len-- > siglen) {
d8baa528 1796 ssh2_pkt_addstring_data(ssh, (char *)newlen, 1);
1dd353b5 1797 /* dmemdump(newlen, 1); */
1798 }
d8baa528 1799 ssh2_pkt_addstring_data(ssh, (char *)(sigblob+pos), siglen);
1dd353b5 1800 /* dmemdump(sigblob+pos, siglen); */
1801 return;
1802 }
1803
1804 /* Otherwise fall through and do it the easy way. */
1805 }
1806
51470298 1807 ssh2_pkt_addstring_start(ssh);
d8baa528 1808 ssh2_pkt_addstring_data(ssh, (char *)sigblob, sigblob_len);
1dd353b5 1809}
1810
1811/*
7d503c31 1812 * Examine the remote side's version string and compare it against
1813 * a list of known buggy implementations.
1814 */
51470298 1815static void ssh_detect_bugs(Ssh ssh, char *vstring)
32874aea 1816{
1817 char *imp; /* pointer to implementation part */
7d503c31 1818 imp = vstring;
1819 imp += strcspn(imp, "-");
bd358db1 1820 if (*imp) imp++;
7d503c31 1821 imp += strcspn(imp, "-");
bd358db1 1822 if (*imp) imp++;
7d503c31 1823
51470298 1824 ssh->remote_bugs = 0;
7d503c31 1825
5ecd7ad0 1826 if (ssh->cfg.sshbug_ignore1 == FORCE_ON ||
1827 (ssh->cfg.sshbug_ignore1 == AUTO &&
2c9c6388 1828 (!strcmp(imp, "1.2.18") || !strcmp(imp, "1.2.19") ||
1829 !strcmp(imp, "1.2.20") || !strcmp(imp, "1.2.21") ||
46ac09aa 1830 !strcmp(imp, "1.2.22") || !strcmp(imp, "Cisco-1.25") ||
bd0b4caf 1831 !strcmp(imp, "OSU_1.4alpha3") || !strcmp(imp, "OSU_1.5alpha4")))) {
32874aea 1832 /*
1833 * These versions don't support SSH1_MSG_IGNORE, so we have
1834 * to use a different defence against password length
1835 * sniffing.
1836 */
51470298 1837 ssh->remote_bugs |= BUG_CHOKES_ON_SSH1_IGNORE;
32874aea 1838 logevent("We believe remote version has SSH1 ignore bug");
7d503c31 1839 }
1840
5ecd7ad0 1841 if (ssh->cfg.sshbug_plainpw1 == FORCE_ON ||
1842 (ssh->cfg.sshbug_plainpw1 == AUTO &&
46ac09aa 1843 (!strcmp(imp, "Cisco-1.25") || !strcmp(imp, "OSU_1.4alpha3")))) {
bd358db1 1844 /*
1845 * These versions need a plain password sent; they can't
1846 * handle having a null and a random length of data after
1847 * the password.
1848 */
51470298 1849 ssh->remote_bugs |= BUG_NEEDS_SSH1_PLAIN_PASSWORD;
bd358db1 1850 logevent("We believe remote version needs a plain SSH1 password");
1851 }
1852
5ecd7ad0 1853 if (ssh->cfg.sshbug_rsa1 == FORCE_ON ||
1854 (ssh->cfg.sshbug_rsa1 == AUTO &&
2c9c6388 1855 (!strcmp(imp, "Cisco-1.25")))) {
0df73905 1856 /*
1857 * These versions apparently have no clue whatever about
1858 * RSA authentication and will panic and die if they see
1859 * an AUTH_RSA message.
1860 */
51470298 1861 ssh->remote_bugs |= BUG_CHOKES_ON_RSA;
0df73905 1862 logevent("We believe remote version can't handle RSA authentication");
1863 }
1864
5ecd7ad0 1865 if (ssh->cfg.sshbug_hmac2 == FORCE_ON ||
1866 (ssh->cfg.sshbug_hmac2 == AUTO &&
b9f387af 1867 !wc_match("* VShell", imp) &&
831301f6 1868 (wc_match("2.1.0*", imp) || wc_match("2.0.*", imp) ||
1869 wc_match("2.2.0*", imp) || wc_match("2.3.0*", imp) ||
1870 wc_match("2.1 *", imp)))) {
32874aea 1871 /*
1872 * These versions have the HMAC bug.
1873 */
51470298 1874 ssh->remote_bugs |= BUG_SSH2_HMAC;
32874aea 1875 logevent("We believe remote version has SSH2 HMAC bug");
7d503c31 1876 }
1dd353b5 1877
5ecd7ad0 1878 if (ssh->cfg.sshbug_derivekey2 == FORCE_ON ||
1879 (ssh->cfg.sshbug_derivekey2 == AUTO &&
b9f387af 1880 !wc_match("* VShell", imp) &&
2856a1b9 1881 (wc_match("2.0.0*", imp) || wc_match("2.0.10*", imp) ))) {
088bde77 1882 /*
1883 * These versions have the key-derivation bug (failing to
1884 * include the literal shared secret in the hashes that
1885 * generate the keys).
1886 */
51470298 1887 ssh->remote_bugs |= BUG_SSH2_DERIVEKEY;
088bde77 1888 logevent("We believe remote version has SSH2 key-derivation bug");
1889 }
1890
5ecd7ad0 1891 if (ssh->cfg.sshbug_rsapad2 == FORCE_ON ||
1892 (ssh->cfg.sshbug_rsapad2 == AUTO &&
831301f6 1893 (wc_match("OpenSSH_2.[5-9]*", imp) ||
1894 wc_match("OpenSSH_3.[0-2]*", imp)))) {
1dd353b5 1895 /*
1896 * These versions have the SSH2 RSA padding bug.
1897 */
51470298 1898 ssh->remote_bugs |= BUG_SSH2_RSA_PADDING;
1dd353b5 1899 logevent("We believe remote version has SSH2 RSA padding bug");
1900 }
8e975795 1901
dda87a28 1902 if (ssh->cfg.sshbug_pksessid2 == FORCE_ON ||
1903 (ssh->cfg.sshbug_pksessid2 == AUTO &&
1904 wc_match("OpenSSH_2.[0-2]*", imp))) {
1905 /*
1906 * These versions have the SSH2 session-ID bug in
1907 * public-key authentication.
1908 */
1909 ssh->remote_bugs |= BUG_SSH2_PK_SESSIONID;
1910 logevent("We believe remote version has SSH2 public-key-session-ID bug");
1911 }
1912
5ecd7ad0 1913 if (ssh->cfg.sshbug_dhgex2 == FORCE_ON) {
8e975795 1914 /*
831301f6 1915 * User specified the SSH2 DH GEX bug.
8e975795 1916 */
51470298 1917 ssh->remote_bugs |= BUG_SSH2_DH_GEX;
8e975795 1918 logevent("We believe remote version has SSH2 DH group exchange bug");
1919 }
7d503c31 1920}
1921
51470298 1922static int do_ssh_init(Ssh ssh, unsigned char c)
32874aea 1923{
51470298 1924 struct do_ssh_init_state {
1925 int vslen;
1926 char version[10];
1927 char *vstring;
1928 int vstrsize;
1929 int i;
1930 int proto1, proto2;
1931 };
1932 crState(do_ssh_init_state);
374330e2 1933
51470298 1934 crBegin(ssh->do_ssh_init_crstate);
8df7a775 1935
1936 /* Search for the string "SSH-" in the input. */
51470298 1937 s->i = 0;
8df7a775 1938 while (1) {
1939 static const int transS[] = { 1, 2, 2, 1 };
1940 static const int transH[] = { 0, 0, 3, 0 };
1941 static const int transminus[] = { 0, 0, 0, -1 };
32874aea 1942 if (c == 'S')
51470298 1943 s->i = transS[s->i];
32874aea 1944 else if (c == 'H')
51470298 1945 s->i = transH[s->i];
32874aea 1946 else if (c == '-')
51470298 1947 s->i = transminus[s->i];
32874aea 1948 else
51470298 1949 s->i = 0;
1950 if (s->i < 0)
8df7a775 1951 break;
1952 crReturn(1); /* get another character */
374330e2 1953 }
8df7a775 1954
51470298 1955 s->vstrsize = 16;
3d88e64d 1956 s->vstring = snewn(s->vstrsize, char);
51470298 1957 strcpy(s->vstring, "SSH-");
1958 s->vslen = 4;
1959 s->i = 0;
374330e2 1960 while (1) {
8df7a775 1961 crReturn(1); /* get another char */
51470298 1962 if (s->vslen >= s->vstrsize - 1) {
1963 s->vstrsize += 16;
3d88e64d 1964 s->vstring = sresize(s->vstring, s->vstrsize, char);
32874aea 1965 }
51470298 1966 s->vstring[s->vslen++] = c;
1967 if (s->i >= 0) {
374330e2 1968 if (c == '-') {
51470298 1969 s->version[s->i] = '\0';
1970 s->i = -1;
1971 } else if (s->i < sizeof(s->version) - 1)
1972 s->version[s->i++] = c;
c4ffc4d0 1973 } else if (c == '\012')
374330e2 1974 break;
1975 }
1976
51470298 1977 ssh->agentfwd_enabled = FALSE;
1978 ssh->rdpkt2_state.incoming_sequence = 0;
960e736a 1979
51470298 1980 s->vstring[s->vslen] = 0;
1981 s->vstring[strcspn(s->vstring, "\r\n")] = '\0';/* remove EOL chars */
1982 {
1983 char *vlog;
3d88e64d 1984 vlog = snewn(20 + s->vslen, char);
51470298 1985 sprintf(vlog, "Server version: %s", s->vstring);
1986 logevent(vlog);
1987 sfree(vlog);
1988 }
1989 ssh_detect_bugs(ssh, s->vstring);
c5e9c988 1990
adf799dd 1991 /*
38d228a2 1992 * Decide which SSH protocol version to support.
adf799dd 1993 */
38d228a2 1994
1995 /* Anything strictly below "2.0" means protocol 1 is supported. */
51470298 1996 s->proto1 = ssh_versioncmp(s->version, "2.0") < 0;
38d228a2 1997 /* Anything greater or equal to "1.99" means protocol 2 is supported. */
51470298 1998 s->proto2 = ssh_versioncmp(s->version, "1.99") >= 0;
38d228a2 1999
86916870 2000 if (ssh->cfg.sshprot == 0 && !s->proto1) {
6b5cf8b4 2001 bombout(("SSH protocol version 1 required by user but not provided by server"));
7ffdbc1a 2002 crStop(0);
38d228a2 2003 }
86916870 2004 if (ssh->cfg.sshprot == 3 && !s->proto2) {
6b5cf8b4 2005 bombout(("SSH protocol version 2 required by user but not provided by server"));
7ffdbc1a 2006 crStop(0);
38d228a2 2007 }
2008
86916870 2009 if (s->proto2 && (ssh->cfg.sshprot >= 2 || !s->proto1)) {
32874aea 2010 /*
38d228a2 2011 * Use v2 protocol.
32874aea 2012 */
2013 char verstring[80], vlog[100];
2014 sprintf(verstring, "SSH-2.0-%s", sshver);
51470298 2015 SHA_Init(&ssh->exhashbase);
32874aea 2016 /*
2017 * Hash our version string and their version string.
2018 */
51470298 2019 sha_string(&ssh->exhashbase, verstring, strlen(verstring));
2020 sha_string(&ssh->exhashbase, s->vstring, strcspn(s->vstring, "\r\n"));
32874aea 2021 sprintf(vlog, "We claim version: %s", verstring);
2022 logevent(vlog);
c4ffc4d0 2023 strcat(verstring, "\012");
32874aea 2024 logevent("Using SSH protocol version 2");
51470298 2025 sk_write(ssh->s, verstring, strlen(verstring));
2026 ssh->protocol = ssh2_protocol;
2027 ssh->version = 2;
2028 ssh->s_rdpkt = ssh2_rdpkt;
e5574168 2029 } else {
32874aea 2030 /*
38d228a2 2031 * Use v1 protocol.
32874aea 2032 */
2033 char verstring[80], vlog[100];
2034 sprintf(verstring, "SSH-%s-%s",
51470298 2035 (ssh_versioncmp(s->version, "1.5") <= 0 ? s->version : "1.5"),
32874aea 2036 sshver);
2037 sprintf(vlog, "We claim version: %s", verstring);
2038 logevent(vlog);
c4ffc4d0 2039 strcat(verstring, "\012");
759712a6 2040
32874aea 2041 logevent("Using SSH protocol version 1");
51470298 2042 sk_write(ssh->s, verstring, strlen(verstring));
2043 ssh->protocol = ssh1_protocol;
2044 ssh->version = 1;
2045 ssh->s_rdpkt = ssh1_rdpkt;
e5574168 2046 }
125105d1 2047 update_specials_menu(ssh->frontend);
51470298 2048 ssh->state = SSH_STATE_BEFORE_SIZE;
8df7a775 2049
51470298 2050 sfree(s->vstring);
50526e47 2051
8df7a775 2052 crFinish(0);
2053}
2054
51470298 2055static void ssh_gotdata(Ssh ssh, unsigned char *data, int datalen)
8df7a775 2056{
51470298 2057 crBegin(ssh->ssh_gotdata_crstate);
8df7a775 2058
2059 /*
2060 * To begin with, feed the characters one by one to the
2061 * protocol initialisation / selection function do_ssh_init().
2062 * When that returns 0, we're done with the initial greeting
2063 * exchange and can move on to packet discipline.
2064 */
2065 while (1) {
51470298 2066 int ret; /* need not be kept across crReturn */
8df7a775 2067 if (datalen == 0)
2068 crReturnV; /* more data please */
51470298 2069 ret = do_ssh_init(ssh, *data);
32874aea 2070 data++;
2071 datalen--;
8df7a775 2072 if (ret == 0)
2073 break;
2074 }
2075
2076 /*
2077 * We emerge from that loop when the initial negotiation is
2078 * over and we have selected an s_rdpkt function. Now pass
2079 * everything to s_rdpkt, and then pass the resulting packets
2080 * to the proper protocol handler.
2081 */
2082 if (datalen == 0)
2083 crReturnV;
2084 while (1) {
2085 while (datalen > 0) {
51470298 2086 if (ssh->s_rdpkt(ssh, &data, &datalen) == 0) {
2087 if (ssh->state == SSH_STATE_CLOSED) {
e14d0f19 2088 return;
2089 }
51470298 2090 ssh->protocol(ssh, NULL, 0, 1);
2091 if (ssh->state == SSH_STATE_CLOSED) {
8df7a775 2092 return;
2093 }
2094 }
2095 }
2096 crReturnV;
2097 }
2098 crFinishV;
2099}
2100
36f94d1f 2101static void ssh_do_close(Ssh ssh)
32874aea 2102{
36f94d1f 2103 int i;
2104 struct ssh_channel *c;
2105
51470298 2106 ssh->state = SSH_STATE_CLOSED;
2107 if (ssh->s) {
2108 sk_close(ssh->s);
2109 ssh->s = NULL;
f3ab576e 2110 }
36f94d1f 2111 /*
2112 * Now we must shut down any port and X forwardings going
2113 * through this connection.
2114 */
74a98066 2115 if (ssh->channels) {
2116 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
2117 switch (c->type) {
2118 case CHAN_X11:
2119 x11_close(c->u.x11.s);
2120 break;
2121 case CHAN_SOCKDATA:
2122 pfd_close(c->u.pfd.s);
2123 break;
2124 }
2125 del234(ssh->channels, c);
2126 if (ssh->version == 2)
2127 bufchain_clear(&c->v.v2.outbuffer);
2128 sfree(c);
36f94d1f 2129 }
36f94d1f 2130 }
2131}
2132
cbe2d68f 2133static int ssh_closing(Plug plug, const char *error_msg, int error_code,
36f94d1f 2134 int calling_back)
2135{
2136 Ssh ssh = (Ssh) plug;
2137 ssh_do_close(ssh);
7e78000d 2138 if (error_msg) {
32874aea 2139 /* A socket error has occurred. */
247308b5 2140 logevent(error_msg);
971bcc0a 2141 connection_fatal(ssh->frontend, "%s", error_msg);
7e78000d 2142 } else {
2143 /* Otherwise, the remote side closed the connection normally. */
8df7a775 2144 }
7e78000d 2145 return 0;
2146}
2147
32874aea 2148static int ssh_receive(Plug plug, int urgent, char *data, int len)
2149{
51470298 2150 Ssh ssh = (Ssh) plug;
d8baa528 2151 ssh_gotdata(ssh, (unsigned char *)data, len);
51470298 2152 if (ssh->state == SSH_STATE_CLOSED) {
36f94d1f 2153 ssh_do_close(ssh);
32874aea 2154 return 0;
3257deae 2155 }
fef97f43 2156 return 1;
374330e2 2157}
2158
5471d09a 2159static void ssh_sent(Plug plug, int bufsize)
2160{
51470298 2161 Ssh ssh = (Ssh) plug;
5471d09a 2162 /*
2163 * If the send backlog on the SSH socket itself clears, we
2164 * should unthrottle the whole world if it was throttled.
2165 */
2166 if (bufsize < SSH_MAX_BACKLOG)
51470298 2167 ssh_throttle_all(ssh, 0, bufsize);
5471d09a 2168}
2169
fb09bf1c 2170/*
8df7a775 2171 * Connect to specified host and port.
2172 * Returns an error message, or NULL on success.
6e1ebb76 2173 * Also places the canonical host name into `realhost'. It must be
2174 * freed by the caller.
8df7a775 2175 */
cbe2d68f 2176static const char *connect_to_host(Ssh ssh, char *host, int port,
79bf227b 2177 char **realhost, int nodelay, int keepalive)
8df7a775 2178{
51470298 2179 static const struct plug_function_table fn_table = {
7e78000d 2180 ssh_closing,
5471d09a 2181 ssh_receive,
2182 ssh_sent,
2183 NULL
51470298 2184 };
7e78000d 2185
8df7a775 2186 SockAddr addr;
cbe2d68f 2187 const char *err;
8df7a775 2188
3d88e64d 2189 ssh->savedhost = snewn(1 + strlen(host), char);
51470298 2190 if (!ssh->savedhost)
8df7a775 2191 fatalbox("Out of memory");
51470298 2192 strcpy(ssh->savedhost, host);
8df7a775 2193
2194 if (port < 0)
2195 port = 22; /* default ssh port */
51470298 2196 ssh->savedport = port;
8df7a775 2197
2198 /*
2199 * Try to find host.
2200 */
57356d63 2201 logeventf(ssh, "Looking up host \"%s\"", host);
e8fa8f62 2202 addr = name_lookup(host, port, realhost, &ssh->cfg);
170c1e6e 2203 if ((err = sk_addr_error(addr)) != NULL) {
2204 sk_addr_free(addr);
8df7a775 2205 return err;
170c1e6e 2206 }
8df7a775 2207
8df7a775 2208 /*
2209 * Open socket.
2210 */
3ad9d396 2211 {
57356d63 2212 char addrbuf[100];
3ad9d396 2213 sk_getaddr(addr, addrbuf, 100);
57356d63 2214 logeventf(ssh, "Connecting to %s port %d", addrbuf, port);
3ad9d396 2215 }
51470298 2216 ssh->fn = &fn_table;
e8fa8f62 2217 ssh->s = new_connection(addr, *realhost, port,
79bf227b 2218 0, 1, nodelay, keepalive, (Plug) ssh, &ssh->cfg);
70e5d0fd 2219 if ((err = sk_socket_error(ssh->s)) != NULL) {
51470298 2220 ssh->s = NULL;
8df7a775 2221 return err;
67c4ba2e 2222 }
8df7a775 2223
8df7a775 2224 return NULL;
2225}
2226
2227/*
5471d09a 2228 * Throttle or unthrottle the SSH connection.
2229 */
51470298 2230static void ssh1_throttle(Ssh ssh, int adjust)
5471d09a 2231{
51470298 2232 int old_count = ssh->v1_throttle_count;
2233 ssh->v1_throttle_count += adjust;
2234 assert(ssh->v1_throttle_count >= 0);
2235 if (ssh->v1_throttle_count && !old_count) {
2236 sk_set_frozen(ssh->s, 1);
2237 } else if (!ssh->v1_throttle_count && old_count) {
2238 sk_set_frozen(ssh->s, 0);
5471d09a 2239 }
2240}
2241
2242/*
2243 * Throttle or unthrottle _all_ local data streams (for when sends
2244 * on the SSH connection itself back up).
2245 */
51470298 2246static void ssh_throttle_all(Ssh ssh, int enable, int bufsize)
5471d09a 2247{
2248 int i;
2249 struct ssh_channel *c;
2250
51470298 2251 if (enable == ssh->throttled_all)
5471d09a 2252 return;
51470298 2253 ssh->throttled_all = enable;
2254 ssh->overall_bufsize = bufsize;
2255 if (!ssh->channels)
5471d09a 2256 return;
51470298 2257 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
5471d09a 2258 switch (c->type) {
2259 case CHAN_MAINSESSION:
2260 /*
2261 * This is treated separately, outside the switch.
2262 */
2263 break;
2264 case CHAN_X11:
2265 x11_override_throttle(c->u.x11.s, enable);
2266 break;
2267 case CHAN_AGENT:
2268 /* Agent channels require no buffer management. */
2269 break;
2270 case CHAN_SOCKDATA:
36f94d1f 2271 pfd_override_throttle(c->u.pfd.s, enable);
5471d09a 2272 break;
2273 }
2274 }
2275}
2276
2277/*
51470298 2278 * Username and password input, abstracted off into routines
2279 * reusable in several places - even between SSH1 and SSH2.
0405e71f 2280 */
0405e71f 2281
2282/* Set up a username or password input loop on a given buffer. */
ae9ae89f 2283static void setup_userpass_input(Ssh ssh, char *buffer, int buflen, int echo)
0405e71f 2284{
51470298 2285 ssh->userpass_input_buffer = buffer;
2286 ssh->userpass_input_buflen = buflen;
2287 ssh->userpass_input_bufpos = 0;
2288 ssh->userpass_input_echo = echo;
0405e71f 2289}
2290
2291/*
2292 * Process some terminal data in the course of username/password
2293 * input. Returns >0 for success (line of input returned in
2294 * buffer), <0 for failure (user hit ^C/^D, bomb out and exit), 0
2295 * for inconclusive (keep waiting for more input please).
2296 */
ae9ae89f 2297static int process_userpass_input(Ssh ssh, unsigned char *in, int inlen)
0405e71f 2298{
2299 char c;
2300
2301 while (inlen--) {
2302 switch (c = *in++) {
2303 case 10:
2304 case 13:
51470298 2305 ssh->userpass_input_buffer[ssh->userpass_input_bufpos] = 0;
2306 ssh->userpass_input_buffer[ssh->userpass_input_buflen-1] = 0;
0405e71f 2307 return +1;
2308 break;
2309 case 8:
2310 case 127:
51470298 2311 if (ssh->userpass_input_bufpos > 0) {
2312 if (ssh->userpass_input_echo)
2313 c_write_str(ssh, "\b \b");
2314 ssh->userpass_input_bufpos--;
0405e71f 2315 }
2316 break;
2317 case 21:
2318 case 27:
51470298 2319 while (ssh->userpass_input_bufpos > 0) {
2320 if (ssh->userpass_input_echo)
2321 c_write_str(ssh, "\b \b");
2322 ssh->userpass_input_bufpos--;
0405e71f 2323 }
2324 break;
2325 case 3:
2326 case 4:
2327 return -1;
2328 break;
2329 default:
4692a14a 2330 /*
2331 * This simplistic check for printability is disabled
2332 * when we're doing password input, because some people
2333 * have control characters in their passwords.o
2334 */
2335 if ((!ssh->userpass_input_echo ||
2336 (c >= ' ' && c <= '~') ||
0405e71f 2337 ((unsigned char) c >= 160))
51470298 2338 && ssh->userpass_input_bufpos < ssh->userpass_input_buflen-1) {
2339 ssh->userpass_input_buffer[ssh->userpass_input_bufpos++] = c;
2340 if (ssh->userpass_input_echo)
2341 c_write(ssh, &c, 1);
0405e71f 2342 }
2343 break;
2344 }
2345 }
2346 return 0;
2347}
2348
f11d78f2 2349static void ssh_agent_callback(void *sshv, void *reply, int replylen)
839f10db 2350{
2351 Ssh ssh = (Ssh) sshv;
2352
2353 ssh->agent_response = reply;
2354 ssh->agent_response_len = replylen;
2355
2356 if (ssh->version == 1)
2357 do_ssh1_login(ssh, NULL, -1, 0);
2358 else
2359 do_ssh2_authconn(ssh, NULL, -1, 0);
2360}
2361
f11d78f2 2362static void ssh_agentf_callback(void *cv, void *reply, int replylen)
839f10db 2363{
2364 struct ssh_channel *c = (struct ssh_channel *)cv;
2365 Ssh ssh = c->ssh;
2366 void *sentreply = reply;
2367
2368 if (!sentreply) {
2369 /* Fake SSH_AGENT_FAILURE. */
2370 sentreply = "\0\0\0\1\5";
2371 replylen = 5;
2372 }
2373 if (ssh->version == 2) {
2374 ssh2_add_channel_data(c, sentreply, replylen);
2375 ssh2_try_send(c);
2376 } else {
2377 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
2378 PKT_INT, c->remoteid,
2379 PKT_INT, replylen,
2380 PKT_DATA, sentreply, replylen,
2381 PKT_END);
2382 }
2383 if (reply)
2384 sfree(reply);
2385}
2386
0405e71f 2387/*
fb09bf1c 2388 * Handle the key exchange and user authentication phases.
2389 */
51470298 2390static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
fb09bf1c 2391{
0016d70b 2392 int i, j, ret;
2393 unsigned char cookie[8], *ptr;
374330e2 2394 struct RSAKey servkey, hostkey;
2395 struct MD5Context md5c;
51470298 2396 struct do_ssh1_login_state {
2397 int len;
2398 unsigned char *rsabuf, *keystr1, *keystr2;
2399 unsigned long supported_ciphers_mask, supported_auths_mask;
2400 int tried_publickey, tried_agent;
2401 int tis_auth_refused, ccard_auth_refused;
2402 unsigned char session_id[16];
2403 int cipher_type;
2404 char username[100];
2405 void *publickey_blob;
2406 int publickey_bloblen;
2407 char password[100];
2408 char prompt[200];
2409 int pos;
2410 char c;
2411 int pwpkt_type;
2412 unsigned char request[5], *response, *p;
2413 int responselen;
2414 int keyi, nkeys;
2415 int authed;
2416 struct RSAKey key;
2417 Bignum challenge;
2418 char *commentp;
2419 int commentlen;
2420 };
2421 crState(do_ssh1_login_state);
2422
2423 crBegin(ssh->do_ssh1_login_crstate);
374330e2 2424
32874aea 2425 if (!ispkt)
2426 crWaitUntil(ispkt);
374330e2 2427
51470298 2428 if (ssh->pktin.type != SSH1_SMSG_PUBLIC_KEY) {
6b5cf8b4 2429 bombout(("Public key packet not received"));
7ffdbc1a 2430 crStop(0);
8d5de777 2431 }
374330e2 2432
c5e9c988 2433 logevent("Received public keys");
374330e2 2434
0016d70b 2435 ptr = ssh_pkt_getdata(ssh, 8);
2436 if (!ptr) {
2437 bombout(("SSH1 public key packet stopped before random cookie"));
2438 crStop(0);
2439 }
2440 memcpy(cookie, ptr, 8);
374330e2 2441
0016d70b 2442 if (!ssh1_pkt_getrsakey(ssh, &servkey, &s->keystr1) ||
2443 !ssh1_pkt_getrsakey(ssh, &hostkey, &s->keystr2)) {
ae0500e5 2444 bombout(("Failed to read SSH1 public keys from public key packet"));
0016d70b 2445 crStop(0);
2446 }
374330e2 2447
c5e9c988 2448 /*
1c2a93c4 2449 * Log the host key fingerprint.
c5e9c988 2450 */
c5e9c988 2451 {
2452 char logmsg[80];
1c2a93c4 2453 logevent("Host key fingerprint is:");
c5e9c988 2454 strcpy(logmsg, " ");
32874aea 2455 hostkey.comment = NULL;
2456 rsa_fingerprint(logmsg + strlen(logmsg),
2457 sizeof(logmsg) - strlen(logmsg), &hostkey);
c5e9c988 2458 logevent(logmsg);
2459 }
2460
0016d70b 2461 ssh->v1_remote_protoflags = ssh_pkt_getuint32(ssh);
2462 s->supported_ciphers_mask = ssh_pkt_getuint32(ssh);
2463 s->supported_auths_mask = ssh_pkt_getuint32(ssh);
bea1ef5f 2464
51470298 2465 ssh->v1_local_protoflags =
2466 ssh->v1_remote_protoflags & SSH1_PROTOFLAGS_SUPPORTED;
2467 ssh->v1_local_protoflags |= SSH1_PROTOFLAG_SCREEN_NUMBER;
b96dc54c 2468
c5e9c988 2469 MD5Init(&md5c);
51470298 2470 MD5Update(&md5c, s->keystr2, hostkey.bytes);
2471 MD5Update(&md5c, s->keystr1, servkey.bytes);
0016d70b 2472 MD5Update(&md5c, cookie, 8);
51470298 2473 MD5Final(s->session_id, &md5c);
374330e2 2474
32874aea 2475 for (i = 0; i < 32; i++)
51470298 2476 ssh->session_key[i] = random_byte();
374330e2 2477
0016d70b 2478 /*
2479 * Verify that the `bits' and `bytes' parameters match.
2480 */
2481 if (hostkey.bits > hostkey.bytes * 8 ||
2482 servkey.bits > servkey.bytes * 8) {
2483 bombout(("SSH1 public keys were badly formatted"));
2484 crStop(0);
2485 }
2486
51470298 2487 s->len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
374330e2 2488
3d88e64d 2489 s->rsabuf = snewn(s->len, unsigned char);
51470298 2490 if (!s->rsabuf)
374330e2 2491 fatalbox("Out of memory");
2492
89ee5268 2493 /*
2494 * Verify the host key.
2495 */
2496 {
32874aea 2497 /*
2498 * First format the key into a string.
2499 */
2500 int len = rsastr_len(&hostkey);
2501 char fingerprint[100];
3d88e64d 2502 char *keystr = snewn(len, char);
32874aea 2503 if (!keystr)
2504 fatalbox("Out of memory");
2505 rsastr_fmt(keystr, &hostkey);
2506 rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
a8327734 2507 verify_ssh_host_key(ssh->frontend,
2508 ssh->savedhost, ssh->savedport, "rsa", keystr,
32874aea 2509 fingerprint);
2510 sfree(keystr);
2511 }
2512
2513 for (i = 0; i < 32; i++) {
51470298 2514 s->rsabuf[i] = ssh->session_key[i];
374330e2 2515 if (i < 16)
51470298 2516 s->rsabuf[i] ^= s->session_id[i];
374330e2 2517 }
2518
2519 if (hostkey.bytes > servkey.bytes) {
0016d70b 2520 ret = rsaencrypt(s->rsabuf, 32, &servkey);
2521 if (ret)
2522 ret = rsaencrypt(s->rsabuf, servkey.bytes, &hostkey);
374330e2 2523 } else {
0016d70b 2524 ret = rsaencrypt(s->rsabuf, 32, &hostkey);
2525 if (ret)
2526 ret = rsaencrypt(s->rsabuf, hostkey.bytes, &servkey);
2527 }
2528 if (!ret) {
2529 bombout(("SSH1 public key encryptions failed due to bad formatting"));
2530 crStop(0);
374330e2 2531 }
2532
c5e9c988 2533 logevent("Encrypted session key");
2534
ca20bfcf 2535 {
2536 int cipher_chosen = 0, warn = 0;
2537 char *cipher_string = NULL;
51470298 2538 int i;
ca20bfcf 2539 for (i = 0; !cipher_chosen && i < CIPHER_MAX; i++) {
86916870 2540 int next_cipher = ssh->cfg.ssh_cipherlist[i];
ca20bfcf 2541 if (next_cipher == CIPHER_WARN) {
2542 /* If/when we choose a cipher, warn about it */
2543 warn = 1;
2544 } else if (next_cipher == CIPHER_AES) {
2545 /* XXX Probably don't need to mention this. */
2546 logevent("AES not supported in SSH1, skipping");
2547 } else {
2548 switch (next_cipher) {
51470298 2549 case CIPHER_3DES: s->cipher_type = SSH_CIPHER_3DES;
ca20bfcf 2550 cipher_string = "3DES"; break;
51470298 2551 case CIPHER_BLOWFISH: s->cipher_type = SSH_CIPHER_BLOWFISH;
ca20bfcf 2552 cipher_string = "Blowfish"; break;
51470298 2553 case CIPHER_DES: s->cipher_type = SSH_CIPHER_DES;
ca20bfcf 2554 cipher_string = "single-DES"; break;
2555 }
51470298 2556 if (s->supported_ciphers_mask & (1 << s->cipher_type))
ca20bfcf 2557 cipher_chosen = 1;
2558 }
2559 }
2560 if (!cipher_chosen) {
51470298 2561 if ((s->supported_ciphers_mask & (1 << SSH_CIPHER_3DES)) == 0)
6b5cf8b4 2562 bombout(("Server violates SSH 1 protocol by not "
ca20bfcf 2563 "supporting 3DES encryption"));
2564 else
2565 /* shouldn't happen */
6b5cf8b4 2566 bombout(("No supported ciphers found"));
7ffdbc1a 2567 crStop(0);
a99a05c0 2568 }
ca20bfcf 2569
2570 /* Warn about chosen cipher if necessary. */
2571 if (warn)
a8327734 2572 askcipher(ssh->frontend, cipher_string, 0);
bea1ef5f 2573 }
ca20bfcf 2574
51470298 2575 switch (s->cipher_type) {
32874aea 2576 case SSH_CIPHER_3DES:
2577 logevent("Using 3DES encryption");
2578 break;
2579 case SSH_CIPHER_DES:
2580 logevent("Using single-DES encryption");
2581 break;
2582 case SSH_CIPHER_BLOWFISH:
2583 logevent("Using Blowfish encryption");
2584 break;
c5e9c988 2585 }
bea1ef5f 2586
51470298 2587 send_packet(ssh, SSH1_CMSG_SESSION_KEY,
2588 PKT_CHAR, s->cipher_type,
32874aea 2589 PKT_DATA, cookie, 8,
51470298 2590 PKT_CHAR, (s->len * 8) >> 8, PKT_CHAR, (s->len * 8) & 0xFF,
2591 PKT_DATA, s->rsabuf, s->len,
2592 PKT_INT, ssh->v1_local_protoflags, PKT_END);
fb09bf1c 2593
c5e9c988 2594 logevent("Trying to enable encryption...");
374330e2 2595
51470298 2596 sfree(s->rsabuf);
374330e2 2597
51470298 2598 ssh->cipher = (s->cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
2599 s->cipher_type == SSH_CIPHER_DES ? &ssh_des :
2600 &ssh_3des);
371e569c 2601 ssh->v1_cipher_ctx = ssh->cipher->make_context();
2602 ssh->cipher->sesskey(ssh->v1_cipher_ctx, ssh->session_key);
57356d63 2603 logeventf(ssh, "Initialised %s encryption", ssh->cipher->text_name);
374330e2 2604
0183b242 2605 ssh->crcda_ctx = crcda_make_context();
2606 logevent("Installing CRC compensation attack detector");
2607
679539d7 2608 if (servkey.modulus) {
2609 sfree(servkey.modulus);
2610 servkey.modulus = NULL;
2611 }
2612 if (servkey.exponent) {
2613 sfree(servkey.exponent);
2614 servkey.exponent = NULL;
2615 }
2616 if (hostkey.modulus) {
2617 sfree(hostkey.modulus);
2618 hostkey.modulus = NULL;
2619 }
2620 if (hostkey.exponent) {
2621 sfree(hostkey.exponent);
2622 hostkey.exponent = NULL;
2623 }
fb09bf1c 2624 crWaitUntil(ispkt);
374330e2 2625
51470298 2626 if (ssh->pktin.type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 2627 bombout(("Encryption not successfully enabled"));
7ffdbc1a 2628 crStop(0);
8d5de777 2629 }
374330e2 2630
c5e9c988 2631 logevent("Successfully started encryption");
2632
374330e2 2633 fflush(stdout);
2634 {
86916870 2635 if ((flags & FLAG_INTERACTIVE) && !*ssh->cfg.username) {
c0a81592 2636 if (ssh_get_line && !ssh_getline_pw_only) {
32874aea 2637 if (!ssh_get_line("login as: ",
51470298 2638 s->username, sizeof(s->username), FALSE)) {
32874aea 2639 /*
2640 * get_line failed to get a username.
2641 * Terminate.
2642 */
2643 logevent("No username provided. Abandoning session.");
3bb2f322 2644 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 2645 crStop(1);
32874aea 2646 }
2647 } else {
51470298 2648 int ret; /* need not be kept over crReturn */
2649 c_write_str(ssh, "login as: ");
2650 ssh->send_ok = 1;
0405e71f 2651
51470298 2652 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
0405e71f 2653 do {
32874aea 2654 crWaitUntil(!ispkt);
51470298 2655 ret = process_userpass_input(ssh, in, inlen);
0405e71f 2656 } while (ret == 0);
2657 if (ret < 0)
2658 cleanup_exit(0);
51470298 2659 c_write_str(ssh, "\r\n");
32874aea 2660 }
2661 } else {
86916870 2662 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
51470298 2663 s->username[sizeof(s->username)-1] = '\0';
374330e2 2664 }
fb09bf1c 2665
51470298 2666 send_packet(ssh, SSH1_CMSG_USER, PKT_STR, s->username, PKT_END);
c5e9c988 2667 {
51470298 2668 char userlog[22 + sizeof(s->username)];
2669 sprintf(userlog, "Sent username \"%s\"", s->username);
c5e9c988 2670 logevent(userlog);
32874aea 2671 if (flags & FLAG_INTERACTIVE &&
2672 (!((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)))) {
3c8e959b 2673 strcat(userlog, "\r\n");
51470298 2674 c_write_str(ssh, userlog);
3c8e959b 2675 }
c5e9c988 2676 }
374330e2 2677 }
2678
fb09bf1c 2679 crWaitUntil(ispkt);
374330e2 2680
51470298 2681 if ((ssh->remote_bugs & BUG_CHOKES_ON_RSA)) {
0df73905 2682 /* We must not attempt PK auth. Pretend we've already tried it. */
51470298 2683 s->tried_publickey = s->tried_agent = 1;
0df73905 2684 } else {
51470298 2685 s->tried_publickey = s->tried_agent = 0;
0df73905 2686 }
51470298 2687 s->tis_auth_refused = s->ccard_auth_refused = 0;
86916870 2688 /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
9a30e26b 2689 if (!filename_is_null(ssh->cfg.keyfile)) {
2690 if (!rsakey_pubblob(&ssh->cfg.keyfile,
222d54dc 2691 &s->publickey_blob, &s->publickey_bloblen, NULL))
51470298 2692 s->publickey_blob = NULL;
396778f1 2693 } else
51470298 2694 s->publickey_blob = NULL;
7cca0d81 2695
51470298 2696 while (ssh->pktin.type == SSH1_SMSG_FAILURE) {
2697 s->pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
614a20a0 2698
51470298 2699 if (agent_exists() && !s->tried_agent) {
32874aea 2700 /*
2701 * Attempt RSA authentication using Pageant.
2702 */
32874aea 2703 void *r;
2704
51470298 2705 s->authed = FALSE;
2706 s->tried_agent = 1;
32874aea 2707 logevent("Pageant is running. Requesting keys.");
2708
2709 /* Request the keys held by the agent. */
51470298 2710 PUT_32BIT(s->request, 1);
2711 s->request[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES;
839f10db 2712 if (!agent_query(s->request, 5, &r, &s->responselen,
2713 ssh_agent_callback, ssh)) {
2714 do {
2715 crReturn(0);
2716 if (ispkt) {
2717 bombout(("Unexpected data from server while waiting"
2718 " for agent response"));
2719 crStop(0);
2720 }
2721 } while (ispkt || inlen > 0);
2722 r = ssh->agent_response;
2723 s->responselen = ssh->agent_response_len;
2724 }
51470298 2725 s->response = (unsigned char *) r;
2726 if (s->response && s->responselen >= 5 &&
2727 s->response[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER) {
2728 s->p = s->response + 5;
2729 s->nkeys = GET_32BIT(s->p);
2730 s->p += 4;
32874aea 2731 {
2732 char buf[64];
51470298 2733 sprintf(buf, "Pageant has %d SSH1 keys", s->nkeys);
32874aea 2734 logevent(buf);
2735 }
51470298 2736 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
32874aea 2737 {
2738 char buf[64];
51470298 2739 sprintf(buf, "Trying Pageant key #%d", s->keyi);
32874aea 2740 logevent(buf);
2741 }
51470298 2742 if (s->publickey_blob &&
2743 !memcmp(s->p, s->publickey_blob,
2744 s->publickey_bloblen)) {
396778f1 2745 logevent("This key matches configured key file");
51470298 2746 s->tried_publickey = 1;
396778f1 2747 }
51470298 2748 s->p += 4;
0016d70b 2749 {
2750 int n, ok = FALSE;
2751 do { /* do while (0) to make breaking easy */
2752 n = ssh1_read_bignum
2753 (s->p, s->responselen-(s->p-s->response),
2754 &s->key.exponent);
2755 if (n < 0)
2756 break;
2757 s->p += n;
2758 n = ssh1_read_bignum
2759 (s->p, s->responselen-(s->p-s->response),
2760 &s->key.modulus);
2761 if (n < 0)
2762 break;
2763 s->p += n;
2764 if (s->responselen - (s->p-s->response) < 4)
2765 break;
2766 s->commentlen = GET_32BIT(s->p);
2767 s->p += 4;
2768 if (s->responselen - (s->p-s->response) <
2769 s->commentlen)
2770 break;
2771 s->commentp = (char *)s->p;
2772 s->p += s->commentlen;
2773 ok = TRUE;
2774 } while (0);
2775 if (!ok) {
2776 logevent("Pageant key list packet was truncated");
2777 break;
2778 }
2779 }
51470298 2780 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
2781 PKT_BIGNUM, s->key.modulus, PKT_END);
32874aea 2782 crWaitUntil(ispkt);
51470298 2783 if (ssh->pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
32874aea 2784 logevent("Key refused");
2785 continue;
2786 }
2787 logevent("Received RSA challenge");
0016d70b 2788 if ((s->challenge = ssh1_pkt_getmp(ssh)) == NULL) {
2789 bombout(("Server's RSA challenge was badly formatted"));
2790 crStop(0);
2791 }
2792
32874aea 2793 {
2794 char *agentreq, *q, *ret;
2d466ffd 2795 void *vret;
32874aea 2796 int len, retlen;
2797 len = 1 + 4; /* message type, bit count */
51470298 2798 len += ssh1_bignum_length(s->key.exponent);
2799 len += ssh1_bignum_length(s->key.modulus);
2800 len += ssh1_bignum_length(s->challenge);
32874aea 2801 len += 16; /* session id */
2802 len += 4; /* response format */
3d88e64d 2803 agentreq = snewn(4 + len, char);
32874aea 2804 PUT_32BIT(agentreq, len);
2805 q = agentreq + 4;
2806 *q++ = SSH1_AGENTC_RSA_CHALLENGE;
51470298 2807 PUT_32BIT(q, bignum_bitcount(s->key.modulus));
32874aea 2808 q += 4;
51470298 2809 q += ssh1_write_bignum(q, s->key.exponent);
2810 q += ssh1_write_bignum(q, s->key.modulus);
2811 q += ssh1_write_bignum(q, s->challenge);
2812 memcpy(q, s->session_id, 16);
32874aea 2813 q += 16;
2814 PUT_32BIT(q, 1); /* response format */
839f10db 2815 if (!agent_query(agentreq, len + 4, &vret, &retlen,
2816 ssh_agent_callback, ssh)) {
2817 sfree(agentreq);
2818 do {
2819 crReturn(0);
2820 if (ispkt) {
2821 bombout(("Unexpected data from server"
2822 " while waiting for agent"
2823 " response"));
2824 crStop(0);
2825 }
2826 } while (ispkt || inlen > 0);
2827 vret = ssh->agent_response;
2828 retlen = ssh->agent_response_len;
2829 } else
2830 sfree(agentreq);
2d466ffd 2831 ret = vret;
32874aea 2832 if (ret) {
2833 if (ret[4] == SSH1_AGENT_RSA_RESPONSE) {
2834 logevent("Sending Pageant's response");
51470298 2835 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
32874aea 2836 PKT_DATA, ret + 5, 16,
2837 PKT_END);
2838 sfree(ret);
2839 crWaitUntil(ispkt);
51470298 2840 if (ssh->pktin.type == SSH1_SMSG_SUCCESS) {
32874aea 2841 logevent
2842 ("Pageant's response accepted");
2843 if (flags & FLAG_VERBOSE) {
51470298 2844 c_write_str(ssh, "Authenticated using"
2845 " RSA key \"");
2846 c_write(ssh, s->commentp,
2847 s->commentlen);
2848 c_write_str(ssh, "\" from agent\r\n");
32874aea 2849 }
51470298 2850 s->authed = TRUE;
32874aea 2851 } else
2852 logevent
2853 ("Pageant's response not accepted");
2854 } else {
2855 logevent
2856 ("Pageant failed to answer challenge");
2857 sfree(ret);
2858 }
2859 } else {
2860 logevent("No reply received from Pageant");
2861 }
2862 }
51470298 2863 freebn(s->key.exponent);
2864 freebn(s->key.modulus);
2865 freebn(s->challenge);
2866 if (s->authed)
32874aea 2867 break;
2868 }
29b1d0b3 2869 sfree(s->response);
32874aea 2870 }
51470298 2871 if (s->authed)
32874aea 2872 break;
2873 }
9a30e26b 2874 if (!filename_is_null(ssh->cfg.keyfile) && !s->tried_publickey)
51470298 2875 s->pwpkt_type = SSH1_CMSG_AUTH_RSA;
32874aea 2876
86916870 2877 if (ssh->cfg.try_tis_auth &&
51470298 2878 (s->supported_auths_mask & (1 << SSH1_AUTH_TIS)) &&
2879 !s->tis_auth_refused) {
2880 s->pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
32874aea 2881 logevent("Requested TIS authentication");
51470298 2882 send_packet(ssh, SSH1_CMSG_AUTH_TIS, PKT_END);
32874aea 2883 crWaitUntil(ispkt);
51470298 2884 if (ssh->pktin.type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
32874aea 2885 logevent("TIS authentication declined");
2886 if (flags & FLAG_INTERACTIVE)
51470298 2887 c_write_str(ssh, "TIS authentication refused.\r\n");
2888 s->tis_auth_refused = 1;
614a20a0 2889 continue;
32874aea 2890 } else {
0016d70b 2891 char *challenge;
2892 int challengelen;
2893
2894 ssh_pkt_getstring(ssh, &challenge, &challengelen);
2895 if (!challenge) {
2896 bombout(("TIS challenge packet was badly formed"));
2897 crStop(0);
2898 }
32874aea 2899 logevent("Received TIS challenge");
51470298 2900 if (challengelen > sizeof(s->prompt) - 1)
2901 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
0016d70b 2902 memcpy(s->prompt, challenge, challengelen);
614a20a0 2903 /* Prompt heuristic comes from OpenSSH */
51470298 2904 strncpy(s->prompt + challengelen,
2905 memchr(s->prompt, '\n', challengelen) ?
614a20a0 2906 "": "\r\nResponse: ",
51470298 2907 (sizeof s->prompt) - challengelen);
2908 s->prompt[(sizeof s->prompt) - 1] = '\0';
32874aea 2909 }
2910 }
86916870 2911 if (ssh->cfg.try_tis_auth &&
51470298 2912 (s->supported_auths_mask & (1 << SSH1_AUTH_CCARD)) &&
2913 !s->ccard_auth_refused) {
2914 s->pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
32874aea 2915 logevent("Requested CryptoCard authentication");
51470298 2916 send_packet(ssh, SSH1_CMSG_AUTH_CCARD, PKT_END);
32874aea 2917 crWaitUntil(ispkt);
51470298 2918 if (ssh->pktin.type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
32874aea 2919 logevent("CryptoCard authentication declined");
51470298 2920 c_write_str(ssh, "CryptoCard authentication refused.\r\n");
2921 s->ccard_auth_refused = 1;
614a20a0 2922 continue;
32874aea 2923 } else {
0016d70b 2924 char *challenge;
2925 int challengelen;
2926
2927 ssh_pkt_getstring(ssh, &challenge, &challengelen);
2928 if (!challenge) {
2929 bombout(("CryptoCard challenge packet was badly formed"));
2930 crStop(0);
2931 }
32874aea 2932 logevent("Received CryptoCard challenge");
51470298 2933 if (challengelen > sizeof(s->prompt) - 1)
2934 challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
0016d70b 2935 memcpy(s->prompt, challenge, challengelen);
51470298 2936 strncpy(s->prompt + challengelen,
2937 memchr(s->prompt, '\n', challengelen) ?
614a20a0 2938 "" : "\r\nResponse: ",
51470298 2939 sizeof(s->prompt) - challengelen);
2940 s->prompt[sizeof(s->prompt) - 1] = '\0';
32874aea 2941 }
2942 }
51470298 2943 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
2944 sprintf(s->prompt, "%.90s@%.90s's password: ",
2945 s->username, ssh->savedhost);
32874aea 2946 }
51470298 2947 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
32874aea 2948 char *comment = NULL;
231ee168 2949 int type;
2950 char msgbuf[256];
32874aea 2951 if (flags & FLAG_VERBOSE)
51470298 2952 c_write_str(ssh, "Trying public key authentication.\r\n");
6c6d9ed9 2953 logeventf(ssh, "Trying public key \"%s\"",
2954 filename_to_str(&ssh->cfg.keyfile));
9a30e26b 2955 type = key_type(&ssh->cfg.keyfile);
231ee168 2956 if (type != SSH_KEYTYPE_SSH1) {
2957 sprintf(msgbuf, "Key is of wrong type (%s)",
2958 key_type_to_str(type));
2959 logevent(msgbuf);
51470298 2960 c_write_str(ssh, msgbuf);
2961 c_write_str(ssh, "\r\n");
2962 s->tried_publickey = 1;
231ee168 2963 continue;
2964 }
9a30e26b 2965 if (!rsakey_encrypted(&ssh->cfg.keyfile, &comment)) {
32874aea 2966 if (flags & FLAG_VERBOSE)
51470298 2967 c_write_str(ssh, "No passphrase required.\r\n");
32874aea 2968 goto tryauth;
2969 }
51470298 2970 sprintf(s->prompt, "Passphrase for key \"%.100s\": ", comment);
32874aea 2971 sfree(comment);
2972 }
a52f067e 2973
614a20a0 2974 /*
2975 * Show password prompt, having first obtained it via a TIS
2976 * or CryptoCard exchange if we're doing TIS or CryptoCard
2977 * authentication.
2978 */
fa17a66e 2979 if (ssh_get_line) {
51470298 2980 if (!ssh_get_line(s->prompt, s->password,
2981 sizeof(s->password), TRUE)) {
32874aea 2982 /*
2983 * get_line failed to get a password (for example
2984 * because one was supplied on the command line
2985 * which has already failed to work). Terminate.
2986 */
51470298 2987 send_packet(ssh, SSH1_MSG_DISCONNECT,
2bc6a386 2988 PKT_STR, "No more passwords available to try",
2989 PKT_END);
247308b5 2990 logevent("Unable to authenticate");
a8327734 2991 connection_fatal(ssh->frontend, "Unable to authenticate");
3bb2f322 2992 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 2993 crStop(1);
32874aea 2994 }
fb09bf1c 2995 } else {
614a20a0 2996 /* Prompt may have come from server. We've munged it a bit, so
2997 * we know it to be zero-terminated at least once. */
51470298 2998 int ret; /* need not be saved over crReturn */
2999 c_write_untrusted(ssh, s->prompt, strlen(s->prompt));
3000 s->pos = 0;
0405e71f 3001
51470298 3002 setup_userpass_input(ssh, s->password, sizeof(s->password), 0);
0405e71f 3003 do {
32874aea 3004 crWaitUntil(!ispkt);
51470298 3005 ret = process_userpass_input(ssh, in, inlen);
0405e71f 3006 } while (ret == 0);
3007 if (ret < 0)
3008 cleanup_exit(0);
51470298 3009 c_write_str(ssh, "\r\n");
32874aea 3010 }
3011
3012 tryauth:
51470298 3013 if (s->pwpkt_type == SSH1_CMSG_AUTH_RSA) {
32874aea 3014 /*
3015 * Try public key authentication with the specified
3016 * key file.
3017 */
51470298 3018 s->tried_publickey = 1;
3019
3020 {
222d54dc 3021 const char *error = NULL;
3022 int ret = loadrsakey(&ssh->cfg.keyfile, &s->key, s->password,
3023 &error);
51470298 3024 if (ret == 0) {
3025 c_write_str(ssh, "Couldn't load private key from ");
9fab77dc 3026 c_write_str(ssh, filename_to_str(&ssh->cfg.keyfile));
222d54dc 3027 c_write_str(ssh, " (");
3028 c_write_str(ssh, error);
3029 c_write_str(ssh, ").\r\n");
51470298 3030 continue; /* go and try password */
3031 }
3032 if (ret == -1) {
3033 c_write_str(ssh, "Wrong passphrase.\r\n");
3034 s->tried_publickey = 0;
3035 continue; /* try again */
3036 }
32874aea 3037 }
3038
3039 /*
3040 * Send a public key attempt.
3041 */
51470298 3042 send_packet(ssh, SSH1_CMSG_AUTH_RSA,
3043 PKT_BIGNUM, s->key.modulus, PKT_END);
32874aea 3044
3045 crWaitUntil(ispkt);
51470298 3046 if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
3047 c_write_str(ssh, "Server refused our public key.\r\n");
32874aea 3048 continue; /* go and try password */
3049 }
51470298 3050 if (ssh->pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
6b5cf8b4 3051 bombout(("Bizarre response to offer of public key"));
7ffdbc1a 3052 crStop(0);
32874aea 3053 }
32874aea 3054
51470298 3055 {
3056 int i;
3057 unsigned char buffer[32];
3058 Bignum challenge, response;
3059
0016d70b 3060 if ((challenge = ssh1_pkt_getmp(ssh)) == NULL) {
3061 bombout(("Server's RSA challenge was badly formatted"));
3062 crStop(0);
3063 }
51470298 3064 response = rsadecrypt(challenge, &s->key);
3065 freebn(s->key.private_exponent);/* burn the evidence */
32874aea 3066
51470298 3067 for (i = 0; i < 32; i++) {
3068 buffer[i] = bignum_byte(response, 31 - i);
3069 }
3070
3071 MD5Init(&md5c);
3072 MD5Update(&md5c, buffer, 32);
3073 MD5Update(&md5c, s->session_id, 16);
3074 MD5Final(buffer, &md5c);
32874aea 3075
51470298 3076 send_packet(ssh, SSH1_CMSG_AUTH_RSA_RESPONSE,
3077 PKT_DATA, buffer, 16, PKT_END);
3078
3079 freebn(challenge);
3080 freebn(response);
3081 }
32874aea 3082
3083 crWaitUntil(ispkt);
51470298 3084 if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
32874aea 3085 if (flags & FLAG_VERBOSE)
51470298 3086 c_write_str(ssh, "Failed to authenticate with"
3087 " our public key.\r\n");
32874aea 3088 continue; /* go and try password */
51470298 3089 } else if (ssh->pktin.type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 3090 bombout(("Bizarre response to RSA authentication response"));
7ffdbc1a 3091 crStop(0);
32874aea 3092 }
3093
3094 break; /* we're through! */
3095 } else {
51470298 3096 if (s->pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
32874aea 3097 /*
3098 * Defence against traffic analysis: we send a
3099 * whole bunch of packets containing strings of
3100 * different lengths. One of these strings is the
3101 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
3102 * The others are all random data in
3103 * SSH1_MSG_IGNORE packets. This way a passive
3104 * listener can't tell which is the password, and
3105 * hence can't deduce the password length.
3106 *
3107 * Anybody with a password length greater than 16
3108 * bytes is going to have enough entropy in their
3109 * password that a listener won't find it _that_
3110 * much help to know how long it is. So what we'll
3111 * do is:
3112 *
3113 * - if password length < 16, we send 15 packets
3114 * containing string lengths 1 through 15
3115 *
3116 * - otherwise, we let N be the nearest multiple
3117 * of 8 below the password length, and send 8
3118 * packets containing string lengths N through
3119 * N+7. This won't obscure the order of
3120 * magnitude of the password length, but it will
3121 * introduce a bit of extra uncertainty.
3122 *
3123 * A few servers (the old 1.2.18 through 1.2.22)
3124 * can't deal with SSH1_MSG_IGNORE. For these
3125 * servers, we need an alternative defence. We make
3126 * use of the fact that the password is interpreted
3127 * as a C string: so we can append a NUL, then some
3128 * random data.
bd358db1 3129 *
3130 * One server (a Cisco one) can deal with neither
3131 * SSH1_MSG_IGNORE _nor_ a padded password string.
3132 * For this server we are left with no defences
3133 * against password length sniffing.
32874aea 3134 */
51470298 3135 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE)) {
b17c8428 3136 /*
3137 * The server can deal with SSH1_MSG_IGNORE, so
3138 * we can use the primary defence.
3139 */
32874aea 3140 int bottom, top, pwlen, i;
3141 char *randomstr;
3142
51470298 3143 pwlen = strlen(s->password);
32874aea 3144 if (pwlen < 16) {
3145 bottom = 0; /* zero length passwords are OK! :-) */
3146 top = 15;
3147 } else {
3148 bottom = pwlen & ~7;
3149 top = bottom + 7;
3150 }
3151
3152 assert(pwlen >= bottom && pwlen <= top);
3153
3d88e64d 3154 randomstr = snewn(top + 1, char);
32874aea 3155
3156 for (i = bottom; i <= top; i++) {
3157 if (i == pwlen)
51470298 3158 defer_packet(ssh, s->pwpkt_type,
3159 PKT_STR, s->password, PKT_END);
32874aea 3160 else {
3161 for (j = 0; j < i; j++) {
3162 do {
3163 randomstr[j] = random_byte();
3164 } while (randomstr[j] == '\0');
3165 }
3166 randomstr[i] = '\0';
51470298 3167 defer_packet(ssh, SSH1_MSG_IGNORE,
32874aea 3168 PKT_STR, randomstr, PKT_END);
3169 }
3170 }
bd358db1 3171 logevent("Sending password with camouflage packets");
51470298 3172 ssh_pkt_defersend(ssh);
679539d7 3173 sfree(randomstr);
bd358db1 3174 }
51470298 3175 else if (!(ssh->remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
b17c8428 3176 /*
3177 * The server can't deal with SSH1_MSG_IGNORE
3178 * but can deal with padded passwords, so we
3179 * can use the secondary defence.
3180 */
bd358db1 3181 char string[64];
51470298 3182 char *ss;
bd358db1 3183 int len;
3184
51470298 3185 len = strlen(s->password);
bd358db1 3186 if (len < sizeof(string)) {
51470298 3187 ss = string;
3188 strcpy(string, s->password);
bd358db1 3189 len++; /* cover the zero byte */
3190 while (len < sizeof(string)) {
3191 string[len++] = (char) random_byte();
3192 }
3193 } else {
51470298 3194 ss = s->password;
bd358db1 3195 }
3196 logevent("Sending length-padded password");
51470298 3197 send_packet(ssh, s->pwpkt_type, PKT_INT, len,
3198 PKT_DATA, ss, len, PKT_END);
bd358db1 3199 } else {
3200 /*
3201 * The server has _both_
3202 * BUG_CHOKES_ON_SSH1_IGNORE and
3203 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
3204 * therefore nothing we can do.
3205 */
3206 int len;
51470298 3207 len = strlen(s->password);
bd358db1 3208 logevent("Sending unpadded password");
51470298 3209 send_packet(ssh, s->pwpkt_type, PKT_INT, len,
3210 PKT_DATA, s->password, len, PKT_END);
32874aea 3211 }
3212 } else {
51470298 3213 send_packet(ssh, s->pwpkt_type, PKT_STR, s->password, PKT_END);
32874aea 3214 }
3215 }
c5e9c988 3216 logevent("Sent password");
51470298 3217 memset(s->password, 0, strlen(s->password));
fb09bf1c 3218 crWaitUntil(ispkt);
51470298 3219 if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
32874aea 3220 if (flags & FLAG_VERBOSE)
51470298 3221 c_write_str(ssh, "Access denied\r\n");
c5e9c988 3222 logevent("Authentication refused");
51470298 3223 } else if (ssh->pktin.type != SSH1_SMSG_SUCCESS) {
6b5cf8b4 3224 bombout(("Strange packet received, type %d", ssh->pktin.type));
7ffdbc1a 3225 crStop(0);
374330e2 3226 }
3227 }
3228
c5e9c988 3229 logevent("Authentication successful");
3230
fb09bf1c 3231 crFinish(1);
3232}
3233
32874aea 3234void sshfwd_close(struct ssh_channel *c)
3235{
51470298 3236 Ssh ssh = c->ssh;
3237
36f94d1f 3238 if (ssh->state != SSH_STATE_SESSION) {
3239 assert(ssh->state == SSH_STATE_CLOSED);
3240 return;
3241 }
3242
80e48603 3243 if (c && !c->closes) {
4ed34d25 3244 /*
3245 * If the channel's remoteid is -1, we have sent
3246 * CHANNEL_OPEN for this channel, but it hasn't even been
3247 * acknowledged by the server. So we must set a close flag
3248 * on it now, and then when the server acks the channel
3249 * open, we can close it then.
3250 */
36cac739 3251 if (((int)c->remoteid) != -1) {
51470298 3252 if (ssh->version == 1) {
3253 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid,
4ed34d25 3254 PKT_END);
3255 } else {
51470298 3256 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_CLOSE);
3257 ssh2_pkt_adduint32(ssh, c->remoteid);
3258 ssh2_pkt_send(ssh);
4ed34d25 3259 }
32874aea 3260 }
0357890f 3261 c->closes = 1; /* sent MSG_CLOSE */
32874aea 3262 if (c->type == CHAN_X11) {
3263 c->u.x11.s = NULL;
d74d141c 3264 logevent("Forwarded X11 connection terminated");
4ed34d25 3265 } else if (c->type == CHAN_SOCKDATA ||
3266 c->type == CHAN_SOCKDATA_DORMANT) {
d74d141c 3267 c->u.pfd.s = NULL;
3268 logevent("Forwarded port closed");
32874aea 3269 }
3270 }
3271}
3272
5471d09a 3273int sshfwd_write(struct ssh_channel *c, char *buf, int len)
32874aea 3274{
51470298 3275 Ssh ssh = c->ssh;
3276
36f94d1f 3277 if (ssh->state != SSH_STATE_SESSION) {
3278 assert(ssh->state == SSH_STATE_CLOSED);
3279 return 0;
3280 }
3281
51470298 3282 if (ssh->version == 1) {
3283 send_packet(ssh, SSH1_MSG_CHANNEL_DATA,
32874aea 3284 PKT_INT, c->remoteid,
3285 PKT_INT, len, PKT_DATA, buf, len, PKT_END);
5471d09a 3286 /*
3287 * In SSH1 we can return 0 here - implying that forwarded
3288 * connections are never individually throttled - because
3289 * the only circumstance that can cause throttling will be
3290 * the whole SSH connection backing up, in which case
3291 * _everything_ will be throttled as a whole.
3292 */
3293 return 0;
783415f8 3294 } else {
32874aea 3295 ssh2_add_channel_data(c, buf, len);
5471d09a 3296 return ssh2_try_send(c);
3297 }
3298}
3299
3300void sshfwd_unthrottle(struct ssh_channel *c, int bufsize)
3301{
51470298 3302 Ssh ssh = c->ssh;
3303
36f94d1f 3304 if (ssh->state != SSH_STATE_SESSION) {
3305 assert(ssh->state == SSH_STATE_CLOSED);
3306 return;
3307 }
3308
51470298 3309 if (ssh->version == 1) {
5471d09a 3310 if (c->v.v1.throttling && bufsize < SSH1_BUFFER_LIMIT) {
3311 c->v.v1.throttling = 0;
51470298 3312 ssh1_throttle(ssh, -1);
5471d09a 3313 }
3314 } else {
3315 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
783415f8 3316 }
9c964e85 3317}
3318
51470298 3319static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
32874aea 3320{
51470298 3321 crBegin(ssh->ssh1_protocol_crstate);
fb09bf1c 3322
3323 random_init();
3324
51470298 3325 while (!do_ssh1_login(ssh, in, inlen, ispkt)) {
fb09bf1c 3326 crReturnV;
85ee8208 3327 }
51470298 3328 if (ssh->state == SSH_STATE_CLOSED)
32874aea 3329 crReturnV;
fb09bf1c 3330
86916870 3331 if (ssh->cfg.agentfwd && agent_exists()) {
32874aea 3332 logevent("Requesting agent forwarding");
51470298 3333 send_packet(ssh, SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
32874aea 3334 do {
3335 crReturnV;
3336 } while (!ispkt);
51470298 3337 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3338 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
6b5cf8b4 3339 bombout(("Protocol confusion"));
7ffdbc1a 3340 crStopV;
51470298 3341 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
32874aea 3342 logevent("Agent forwarding refused");
3343 } else {
3344 logevent("Agent forwarding enabled");
51470298 3345 ssh->agentfwd_enabled = TRUE;
db7d555c 3346 }
dacbd0e8 3347 }
3348
86916870 3349 if (ssh->cfg.x11_forward) {
32874aea 3350 char proto[20], data[64];
3351 logevent("Requesting X11 forwarding");
302121de 3352 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
86916870 3353 data, sizeof(data), ssh->cfg.x11_auth);
3354 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
51470298 3355 if (ssh->v1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) {
3356 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
32874aea 3357 PKT_STR, proto, PKT_STR, data,
86916870 3358 PKT_INT, x11_get_screen_number(ssh->cfg.x11_display),
421d6835 3359 PKT_END);
32874aea 3360 } else {
51470298 3361 send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
32874aea 3362 PKT_STR, proto, PKT_STR, data, PKT_END);
3363 }
3364 do {
3365 crReturnV;
3366 } while (!ispkt);
51470298 3367 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3368 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
6b5cf8b4 3369 bombout(("Protocol confusion"));
7ffdbc1a 3370 crStopV;
51470298 3371 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
32874aea 3372 logevent("X11 forwarding refused");
3373 } else {
3374 logevent("X11 forwarding enabled");
51470298 3375 ssh->X11_fwd_enabled = TRUE;
9c964e85 3376 }
3377 }
3378
d74d141c 3379 {
9bf696b1 3380 char type;
d74d141c 3381 int n;
a4fc0d74 3382 int sport,dport,sserv,dserv;
6ee9b735 3383 char sports[256], dports[256], saddr[256], host[256];
d74d141c 3384
51470298 3385 ssh->rportfwds = newtree234(ssh_rportcmp_ssh1);
d74d141c 3386 /* Add port forwardings. */
86916870 3387 ssh->portfwd_strptr = ssh->cfg.portfwd;
51470298 3388 while (*ssh->portfwd_strptr) {
3389 type = *ssh->portfwd_strptr++;
6ee9b735 3390 saddr[0] = '\0';
d74d141c 3391 n = 0;
6ee9b735 3392 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != '\t') {
3393 if (*ssh->portfwd_strptr == ':') {
3394 /*
3395 * We've seen a colon in the middle of the
3396 * source port number. This means that
3397 * everything we've seen until now is the
3398 * source _address_, so we'll move it into
3399 * saddr and start sports from the beginning
3400 * again.
3401 */
3402 ssh->portfwd_strptr++;
3403 sports[n] = '\0';
3404 strcpy(saddr, sports);
3405 n = 0;
3406 }
3407 if (n < 255) sports[n++] = *ssh->portfwd_strptr++;
3408 }
d74d141c 3409 sports[n] = 0;
820ebe3b 3410 if (type != 'D') {
3411 if (*ssh->portfwd_strptr == '\t')
3412 ssh->portfwd_strptr++;
3413 n = 0;
3414 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != ':') {
3415 if (n < 255) host[n++] = *ssh->portfwd_strptr++;
3416 }
3417 host[n] = 0;
3418 if (*ssh->portfwd_strptr == ':')
3419 ssh->portfwd_strptr++;
3420 n = 0;
3421 while (*ssh->portfwd_strptr) {
3422 if (n < 255) dports[n++] = *ssh->portfwd_strptr++;
3423 }
3424 dports[n] = 0;
51470298 3425 ssh->portfwd_strptr++;
820ebe3b 3426 dport = atoi(dports);
3427 dserv = 0;
3428 if (dport == 0) {
3429 dserv = 1;
3430 dport = net_service_lookup(dports);
3431 if (!dport) {
3432 logeventf(ssh, "Service lookup failed for"
3433 " destination port \"%s\"", dports);
3434 }
a4fc0d74 3435 }
820ebe3b 3436 } else {
3437 while (*ssh->portfwd_strptr) ssh->portfwd_strptr++;
7ffdbc1a 3438 dport = dserv = -1;
7d5b0f4d 3439 ssh->portfwd_strptr++; /* eat the NUL and move to next one */
a4fc0d74 3440 }
d74d141c 3441 sport = atoi(sports);
a4fc0d74 3442 sserv = 0;
3443 if (sport == 0) {
3444 sserv = 1;
68a49acb 3445 sport = net_service_lookup(sports);
3446 if (!sport) {
57356d63 3447 logeventf(ssh, "Service lookup failed for source"
3448 " port \"%s\"", sports);
a4fc0d74 3449 }
3450 }
d74d141c 3451 if (sport && dport) {
94ab1ddf 3452 /* Set up a description of the source port. */
3453 char *sportdesc = dupprintf("%.*s%.*s%.*s%.*s%d%.*s",
3454 (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
3455 (int)(*saddr?1:0), ":",
3456 (int)(sserv ? strlen(sports) : 0), sports,
3457 sserv, "(", sport, sserv, ")");
d74d141c 3458 if (type == 'L') {
94ab1ddf 3459 /* Verbose description of the destination port */
3460 char *dportdesc = dupprintf("%s:%.*s%.*s%d%.*s",
3461 host,
3462 (int)(dserv ? strlen(dports) : 0), dports,
3463 dserv, "(", dport, dserv, ")");
3464 const char *err = pfd_addforward(host, dport,
3465 *saddr ? saddr : NULL,
3466 sport, ssh, &ssh->cfg);
3467 if (err) {
3468 logeventf(ssh, "Local port %s forward to %s"
3469 " failed: %s", sportdesc, dportdesc, err);
3470 } else {
3471 logeventf(ssh, "Local port %s forwarding to %s",
3472 sportdesc, dportdesc);
3473 }
3474 sfree(dportdesc);
820ebe3b 3475 } else if (type == 'D') {
94ab1ddf 3476 const char *err = pfd_addforward(NULL, -1,
3477 *saddr ? saddr : NULL,
3478 sport, ssh, &ssh->cfg);
3479 if (err) {
3480 logeventf(ssh, "Local port %s SOCKS dynamic forward"
3481 " setup failed: %s", sportdesc, err);
3482 } else {
3483 logeventf(ssh, "Local port %s doing SOCKS"
3484 " dynamic forwarding", sportdesc);
3485 }
d74d141c 3486 } else {
3487 struct ssh_rportfwd *pf;
3d88e64d 3488 pf = snew(struct ssh_rportfwd);
bc240b21 3489 strcpy(pf->dhost, host);
3490 pf->dport = dport;
0cd494d7 3491 if (*saddr) {
6ee9b735 3492 logeventf(ssh,
3493 "SSH1 cannot handle source address spec \"%s:%d\"; ignoring",
3494 saddr, sport);
3495 }
51470298 3496 if (add234(ssh->rportfwds, pf) != pf) {
57356d63 3497 logeventf(ssh,
3498 "Duplicate remote port forwarding to %s:%d",
3499 host, dport);
bc240b21 3500 sfree(pf);
d74d141c 3501 } else {
57356d63 3502 logeventf(ssh, "Requesting remote port %.*s%.*s%d%.*s"
3503 " forward to %s:%.*s%.*s%d%.*s",
3504 (int)(sserv ? strlen(sports) : 0), sports,
3505 sserv, "(", sport, sserv, ")",
3506 host,
3507 (int)(dserv ? strlen(dports) : 0), dports,
3508 dserv, "(", dport, dserv, ")");
51470298 3509 send_packet(ssh, SSH1_CMSG_PORT_FORWARD_REQUEST,
d74d141c 3510 PKT_INT, sport,
3511 PKT_STR, host,
3512 PKT_INT, dport,
3513 PKT_END);
9bf696b1 3514 do {
3515 crReturnV;
3516 } while (!ispkt);
51470298 3517 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3518 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
6b5cf8b4 3519 bombout(("Protocol confusion"));
7ffdbc1a 3520 crStopV;
51470298 3521 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
3522 c_write_str(ssh, "Server refused port"
3523 " forwarding\r\n");
9bf696b1 3524 }
3525 logevent("Remote port forwarding enabled");
d74d141c 3526 }
3527 }
94ab1ddf 3528 sfree(sportdesc);
d74d141c 3529 }
3530 }
3531 }
3532
86916870 3533 if (!ssh->cfg.nopty) {
a5dd8467 3534 /* Unpick the terminal-speed string. */
3535 /* XXX perhaps we should allow no speeds to be sent. */
db219738 3536 ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
3537 sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
a5dd8467 3538 /* Send the pty request. */
51470298 3539 send_packet(ssh, SSH1_CMSG_REQUEST_PTY,
86916870 3540 PKT_STR, ssh->cfg.termtype,
51470298 3541 PKT_INT, ssh->term_height,
3542 PKT_INT, ssh->term_width,
a5dd8467 3543 PKT_INT, 0, PKT_INT, 0, /* width,height in pixels */
db219738 3544 PKT_CHAR, 192, PKT_INT, ssh->ispeed, /* TTY_OP_ISPEED */
3545 PKT_CHAR, 193, PKT_INT, ssh->ospeed, /* TTY_OP_OSPEED */
a5dd8467 3546 PKT_CHAR, 0, PKT_END);
51470298 3547 ssh->state = SSH_STATE_INTERMED;
32874aea 3548 do {
3549 crReturnV;
3550 } while (!ispkt);
51470298 3551 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3552 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
6b5cf8b4 3553 bombout(("Protocol confusion"));
7ffdbc1a 3554 crStopV;
51470298 3555 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
3556 c_write_str(ssh, "Server refused to allocate pty\r\n");
3557 ssh->editing = ssh->echoing = 1;
32874aea 3558 }
a5dd8467 3559 logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
db219738 3560 ssh->ospeed, ssh->ispeed);
0965bee0 3561 } else {
51470298 3562 ssh->editing = ssh->echoing = 1;
374330e2 3563 }
3564
86916870 3565 if (ssh->cfg.compression) {
51470298 3566 send_packet(ssh, SSH1_CMSG_REQUEST_COMPRESSION, PKT_INT, 6, PKT_END);
32874aea 3567 do {
3568 crReturnV;
3569 } while (!ispkt);
51470298 3570 if (ssh->pktin.type != SSH1_SMSG_SUCCESS
3571 && ssh->pktin.type != SSH1_SMSG_FAILURE) {
6b5cf8b4 3572 bombout(("Protocol confusion"));
7ffdbc1a 3573 crStopV;
51470298 3574 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
3575 c_write_str(ssh, "Server refused to compress\r\n");
32874aea 3576 }
4ba9b64b 3577 logevent("Started compression");
51470298 3578 ssh->v1_compressing = TRUE;
5366aed8 3579 ssh->cs_comp_ctx = zlib_compress_init();
3580 logevent("Initialised zlib (RFC1950) compression");
3581 ssh->sc_comp_ctx = zlib_decompress_init();
3582 logevent("Initialised zlib (RFC1950) decompression");
4ba9b64b 3583 }
3584
fd5e5847 3585 /*
3586 * Start the shell or command.
3587 *
3588 * Special case: if the first-choice command is an SSH2
3589 * subsystem (hence not usable here) and the second choice
3590 * exists, we fall straight back to that.
3591 */
3592 {
86916870 3593 char *cmd = ssh->cfg.remote_cmd_ptr;
fd5e5847 3594
86916870 3595 if (ssh->cfg.ssh_subsys && ssh->cfg.remote_cmd_ptr2) {
3596 cmd = ssh->cfg.remote_cmd_ptr2;
51470298 3597 ssh->fallback_cmd = TRUE;
fd5e5847 3598 }
3599 if (*cmd)
51470298 3600 send_packet(ssh, SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END);
fd5e5847 3601 else
51470298 3602 send_packet(ssh, SSH1_CMSG_EXEC_SHELL, PKT_END);
fd5e5847 3603 logevent("Started session");
3604 }
374330e2 3605
51470298 3606 ssh->state = SSH_STATE_SESSION;
3607 if (ssh->size_needed)
3608 ssh_size(ssh, ssh->term_width, ssh->term_height);
3609 if (ssh->eof_needed)
3610 ssh_special(ssh, TS_EOF);
374330e2 3611
b9d7bcad 3612 if (ssh->ldisc)
3613 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
51470298 3614 ssh->send_ok = 1;
3615 ssh->channels = newtree234(ssh_channelcmp);
374330e2 3616 while (1) {
3617 crReturnV;
3618 if (ispkt) {
51470298 3619 if (ssh->pktin.type == SSH1_SMSG_STDOUT_DATA ||
3620 ssh->pktin.type == SSH1_SMSG_STDERR_DATA) {
0016d70b 3621 char *string;
3622 int stringlen, bufsize;
3623
3624 ssh_pkt_getstring(ssh, &string, &stringlen);
3625 if (string == NULL) {
3626 bombout(("Incoming terminal data packet was badly formed"));
3627 crStopV;
3628 }
3629
3630 bufsize =
51470298 3631 from_backend(ssh->frontend,
3632 ssh->pktin.type == SSH1_SMSG_STDERR_DATA,
0016d70b 3633 string, stringlen);
51470298 3634 if (!ssh->v1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
3635 ssh->v1_stdout_throttling = 1;
3636 ssh1_throttle(ssh, +1);
5471d09a 3637 }
51470298 3638 } else if (ssh->pktin.type == SSH1_MSG_DISCONNECT) {
3bb2f322 3639 ssh_closing((Plug)ssh, NULL, 0, 0);
c5e9c988 3640 logevent("Received disconnect request");
7ffdbc1a 3641 crStopV;
51470298 3642 } else if (ssh->pktin.type == SSH1_SMSG_X11_OPEN) {
32874aea 3643 /* Remote side is trying to open a channel to talk to our
3644 * X-Server. Give them back a local channel number. */
3645 struct ssh_channel *c;
0016d70b 3646 int remoteid = ssh_pkt_getuint32(ssh);
9c964e85 3647
3648 logevent("Received X11 connect request");
3649 /* Refuse if X11 forwarding is disabled. */
51470298 3650 if (!ssh->X11_fwd_enabled) {
3651 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
0016d70b 3652 PKT_INT, remoteid, PKT_END);
9c964e85 3653 logevent("Rejected X11 connect request");
3654 } else {
3d88e64d 3655 c = snew(struct ssh_channel);
51470298 3656 c->ssh = ssh;
9c964e85 3657
86916870 3658 if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
e8fa8f62 3659 ssh->x11auth, NULL, -1, &ssh->cfg) != NULL) {
0016d70b 3660 logevent("Opening X11 forward connection failed");
32874aea 3661 sfree(c);
51470298 3662 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
0016d70b 3663 PKT_INT, remoteid, PKT_END);
9c964e85 3664 } else {
32874aea 3665 logevent
0016d70b 3666 ("Opening X11 forward connection succeeded");
3667 c->remoteid = remoteid;
51470298 3668 c->localid = alloc_channel_id(ssh);
32874aea 3669 c->closes = 0;
5471d09a 3670 c->v.v1.throttling = 0;
32874aea 3671 c->type = CHAN_X11; /* identify channel type */
51470298 3672 add234(ssh->channels, c);
3673 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
32874aea 3674 PKT_INT, c->remoteid, PKT_INT,
3675 c->localid, PKT_END);
3676 logevent("Opened X11 forward channel");
9c964e85 3677 }
3678 }
51470298 3679 } else if (ssh->pktin.type == SSH1_SMSG_AGENT_OPEN) {
32874aea 3680 /* Remote side is trying to open a channel to talk to our
3681 * agent. Give them back a local channel number. */
3682 struct ssh_channel *c;
0016d70b 3683 int remoteid = ssh_pkt_getuint32(ssh);
db7d555c 3684
3685 /* Refuse if agent forwarding is disabled. */
51470298 3686 if (!ssh->agentfwd_enabled) {
3687 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
0016d70b 3688 PKT_INT, remoteid, PKT_END);
db7d555c 3689 } else {
3d88e64d 3690 c = snew(struct ssh_channel);
51470298 3691 c->ssh = ssh;
0016d70b 3692 c->remoteid = remoteid;
51470298 3693 c->localid = alloc_channel_id(ssh);
db7d555c 3694 c->closes = 0;
5471d09a 3695 c->v.v1.throttling = 0;
32874aea 3696 c->type = CHAN_AGENT; /* identify channel type */
db7d555c 3697 c->u.a.lensofar = 0;
51470298 3698 add234(ssh->channels, c);
3699 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
db7d555c 3700 PKT_INT, c->remoteid, PKT_INT, c->localid,
3701 PKT_END);
3702 }
51470298 3703 } else if (ssh->pktin.type == SSH1_MSG_PORT_OPEN) {
d74d141c 3704 /* Remote side is trying to open a channel to talk to a
3705 * forwarded port. Give them back a local channel number. */
3706 struct ssh_channel *c;
3707 struct ssh_rportfwd pf;
0016d70b 3708 int remoteid;
d74d141c 3709 int hostsize, port;
0016d70b 3710 char *host, buf[1024];
cbe2d68f 3711 const char *e;
3d88e64d 3712 c = snew(struct ssh_channel);
51470298 3713 c->ssh = ssh;
d74d141c 3714
0016d70b 3715 remoteid = ssh_pkt_getuint32(ssh);
3716 ssh_pkt_getstring(ssh, &host, &hostsize);
3717 port = ssh_pkt_getuint32(ssh);
d74d141c 3718
0016d70b 3719 if (hostsize >= lenof(pf.dhost))
3720 hostsize = lenof(pf.dhost)-1;
3721 memcpy(pf.dhost, host, hostsize);
3722 pf.dhost[hostsize] = '\0';
bc240b21 3723 pf.dport = port;
d74d141c 3724
51470298 3725 if (find234(ssh->rportfwds, &pf, NULL) == NULL) {
d74d141c 3726 sprintf(buf, "Rejected remote port open request for %s:%d",
0016d70b 3727 pf.dhost, port);
d74d141c 3728 logevent(buf);
51470298 3729 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
0016d70b 3730 PKT_INT, remoteid, PKT_END);
d74d141c 3731 } else {
3732 sprintf(buf, "Received remote port open request for %s:%d",
0016d70b 3733 pf.dhost, port);
d74d141c 3734 logevent(buf);
0016d70b 3735 e = pfd_newconnect(&c->u.pfd.s, pf.dhost, port,
3736 c, &ssh->cfg);
d74d141c 3737 if (e != NULL) {
3738 char buf[256];
3739 sprintf(buf, "Port open failed: %s", e);
3740 logevent(buf);
3741 sfree(c);
51470298 3742 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
0016d70b 3743 PKT_INT, remoteid, PKT_END);
d74d141c 3744 } else {
0016d70b 3745 c->remoteid = remoteid;
51470298 3746 c->localid = alloc_channel_id(ssh);
d74d141c 3747 c->closes = 0;
5471d09a 3748 c->v.v1.throttling = 0;
d74d141c 3749 c->type = CHAN_SOCKDATA; /* identify channel type */
51470298 3750 add234(ssh->channels, c);
3751 send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
d74d141c 3752 PKT_INT, c->remoteid, PKT_INT,
3753 c->localid, PKT_END);
3754 logevent("Forwarded port opened successfully");
3755 }
3756 }
3757
51470298 3758 } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_OPEN_CONFIRMATION) {
0016d70b 3759 unsigned int remoteid = ssh_pkt_getuint32(ssh);
3760 unsigned int localid = ssh_pkt_getuint32(ssh);
bc240b21 3761 struct ssh_channel *c;
3762
51470298 3763 c = find234(ssh->channels, &remoteid, ssh_channelfind);
bc240b21 3764 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
3765 c->remoteid = localid;
3766 c->type = CHAN_SOCKDATA;
7781f316 3767 c->v.v1.throttling = 0;
bc240b21 3768 pfd_confirm(c->u.pfd.s);
3769 }
d74d141c 3770
4ed34d25 3771 if (c && c->closes) {
3772 /*
3773 * We have a pending close on this channel,
3774 * which we decided on before the server acked
3775 * the channel open. So now we know the
3776 * remoteid, we can close it again.
3777 */
51470298 3778 send_packet(ssh, SSH1_MSG_CHANNEL_CLOSE,
3779 PKT_INT, c->remoteid, PKT_END);
4ed34d25 3780 }
3781
51470298 3782 } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_OPEN_FAILURE) {
0016d70b 3783 unsigned int remoteid = ssh_pkt_getuint32(ssh);
724cface 3784 struct ssh_channel *c;
3785
51470298 3786 c = find234(ssh->channels, &remoteid, ssh_channelfind);
724cface 3787 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
3788 logevent("Forwarded connection refused by server");
3789 pfd_close(c->u.pfd.s);
51470298 3790 del234(ssh->channels, c);
724cface 3791 sfree(c);
3792 }
3793
51470298 3794 } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE ||
3795 ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) {
32874aea 3796 /* Remote side closes a channel. */
0016d70b 3797 unsigned i = ssh_pkt_getuint32(ssh);
32874aea 3798 struct ssh_channel *c;
51470298 3799 c = find234(ssh->channels, &i, ssh_channelfind);
d0d844c1 3800 if (c && ((int)c->remoteid) != -1) {
32874aea 3801 int closetype;
3802 closetype =
51470298 3803 (ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
0357890f 3804
783415f8 3805 if ((c->closes == 0) && (c->type == CHAN_X11)) {
d74d141c 3806 logevent("Forwarded X11 connection terminated");
9c964e85 3807 assert(c->u.x11.s != NULL);
3808 x11_close(c->u.x11.s);
3809 c->u.x11.s = NULL;
3810 }
d74d141c 3811 if ((c->closes == 0) && (c->type == CHAN_SOCKDATA)) {
3812 logevent("Forwarded port closed");
3813 assert(c->u.pfd.s != NULL);
3814 pfd_close(c->u.pfd.s);
3815 c->u.pfd.s = NULL;
3816 }
0357890f 3817
3818 c->closes |= (closetype << 2); /* seen this message */
3819 if (!(c->closes & closetype)) {
51470298 3820 send_packet(ssh, ssh->pktin.type, PKT_INT, c->remoteid,
0357890f 3821 PKT_END);
3822 c->closes |= closetype; /* sent it too */
3823 }
3824
3825 if (c->closes == 15) {
51470298 3826 del234(ssh->channels, c);
32874aea 3827 sfree(c);
3828 }
d0d844c1 3829 } else {
6b5cf8b4 3830 bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
51470298 3831 ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE ? "" :
d0d844c1 3832 "_CONFIRMATION", c ? "half-open" : "nonexistent",
3833 i));
7ffdbc1a 3834 crStopV;
32874aea 3835 }
51470298 3836 } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_DATA) {
32874aea 3837 /* Data sent down one of our channels. */
0016d70b 3838 int i = ssh_pkt_getuint32(ssh);
3839 char *p;
3840 int len;
32874aea 3841 struct ssh_channel *c;
0016d70b 3842
3843 ssh_pkt_getstring(ssh, &p, &len);
3844
51470298 3845 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 3846 if (c) {
7ffdbc1a 3847 int bufsize = 0;
32874aea 3848 switch (c->type) {
3849 case CHAN_X11:
0016d70b 3850 bufsize = x11_send(c->u.x11.s, p, len);
9c964e85 3851 break;
d74d141c 3852 case CHAN_SOCKDATA:
0016d70b 3853 bufsize = pfd_send(c->u.pfd.s, p, len);
bc240b21 3854 break;
32874aea 3855 case CHAN_AGENT:
3856 /* Data for an agent message. Buffer it. */
3857 while (len > 0) {
3858 if (c->u.a.lensofar < 4) {
3859 int l = min(4 - c->u.a.lensofar, len);
3860 memcpy(c->u.a.msglen + c->u.a.lensofar, p,
3861 l);
3862 p += l;
3863 len -= l;
3864 c->u.a.lensofar += l;
3865 }
3866 if (c->u.a.lensofar == 4) {
3867 c->u.a.totallen =
3868 4 + GET_32BIT(c->u.a.msglen);
3d88e64d 3869 c->u.a.message = snewn(c->u.a.totallen,
3870 unsigned char);
32874aea 3871 memcpy(c->u.a.message, c->u.a.msglen, 4);
3872 }
3873 if (c->u.a.lensofar >= 4 && len > 0) {
3874 int l =
3875 min(c->u.a.totallen - c->u.a.lensofar,
3876 len);
3877 memcpy(c->u.a.message + c->u.a.lensofar, p,
3878 l);
3879 p += l;
3880 len -= l;
3881 c->u.a.lensofar += l;
3882 }
3883 if (c->u.a.lensofar == c->u.a.totallen) {
839f10db 3884 void *reply;
32874aea 3885 int replylen;
839f10db 3886 if (agent_query(c->u.a.message,
3887 c->u.a.totallen,
3888 &reply, &replylen,
3889 ssh_agentf_callback, c))
3890 ssh_agentf_callback(c, reply, replylen);
32874aea 3891 sfree(c->u.a.message);
3892 c->u.a.lensofar = 0;
3893 }
3894 }
5471d09a 3895 bufsize = 0; /* agent channels never back up */
32874aea 3896 break;
3897 }
90347b95 3898 if (!c->v.v1.throttling && bufsize > SSH1_BUFFER_LIMIT) {
5471d09a 3899 c->v.v1.throttling = 1;
51470298 3900 ssh1_throttle(ssh, +1);
5471d09a 3901 }
32874aea 3902 }
51470298 3903 } else if (ssh->pktin.type == SSH1_SMSG_SUCCESS) {
972a41c8 3904 /* may be from EXEC_SHELL on some servers */
51470298 3905 } else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
972a41c8 3906 /* may be from EXEC_SHELL on some servers
374330e2 3907 * if no pty is available or in other odd cases. Ignore */
51470298 3908 } else if (ssh->pktin.type == SSH1_SMSG_EXIT_STATUS) {
d8d6c7e5 3909 char buf[100];
0016d70b 3910 ssh->exitcode = ssh_pkt_getuint32(ssh);
d8d6c7e5 3911 sprintf(buf, "Server sent command exit status %d",
51470298 3912 ssh->exitcode);
d8d6c7e5 3913 logevent(buf);
51470298 3914 send_packet(ssh, SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
4252c9cc 3915 /*
3916 * In case `helpful' firewalls or proxies tack
3917 * extra human-readable text on the end of the
3918 * session which we might mistake for another
3919 * encrypted packet, we close the session once
3920 * we've sent EXIT_CONFIRMATION.
3921 */
3bb2f322 3922 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 3923 crStopV;
374330e2 3924 } else {
6b5cf8b4 3925 bombout(("Strange packet received: type %d", ssh->pktin.type));
7ffdbc1a 3926 crStopV;
374330e2 3927 }
3928 } else {
8df7a775 3929 while (inlen > 0) {
3930 int len = min(inlen, 512);
51470298 3931 send_packet(ssh, SSH1_CMSG_STDIN_DATA,
8df7a775 3932 PKT_INT, len, PKT_DATA, in, len, PKT_END);
3933 in += len;
3934 inlen -= len;
3935 }
374330e2 3936 }
3937 }
3938
3939 crFinishV;
3940}
3941
3942/*
e5574168 3943 * Utility routine for decoding comma-separated strings in KEXINIT.
3944 */
32874aea 3945static int in_commasep_string(char *needle, char *haystack, int haylen)
3946{
57356d63 3947 int needlen;
3948 if (!needle || !haystack) /* protect against null pointers */
3949 return 0;
3950 needlen = strlen(needle);
e5574168 3951 while (1) {
32874aea 3952 /*
3953 * Is it at the start of the string?
3954 */
3955 if (haylen >= needlen && /* haystack is long enough */
3956 !memcmp(needle, haystack, needlen) && /* initial match */
3957 (haylen == needlen || haystack[needlen] == ',')
3958 /* either , or EOS follows */
3959 )
3960 return 1;
3961 /*
3962 * If not, search for the next comma and resume after that.
3963 * If no comma found, terminate.
3964 */
3965 while (haylen > 0 && *haystack != ',')
3966 haylen--, haystack++;
3967 if (haylen == 0)
3968 return 0;
3969 haylen--, haystack++; /* skip over comma itself */
e5574168 3970 }
3971}
3972
3973/*
d39f364a 3974 * SSH2 key creation method.
3975 */
d8baa528 3976static void ssh2_mkkey(Ssh ssh, Bignum K, unsigned char *H,
3977 unsigned char *sessid, char chr,
3978 unsigned char *keyspace)
32874aea 3979{
d39f364a 3980 SHA_State s;
3981 /* First 20 bytes. */
3982 SHA_Init(&s);
51470298 3983 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
088bde77 3984 sha_mpint(&s, K);
d39f364a 3985 SHA_Bytes(&s, H, 20);
3986 SHA_Bytes(&s, &chr, 1);
5e0d7cb8 3987 SHA_Bytes(&s, sessid, 20);
d39f364a 3988 SHA_Final(&s, keyspace);
3989 /* Next 20 bytes. */
3990 SHA_Init(&s);
51470298 3991 if (!(ssh->remote_bugs & BUG_SSH2_DERIVEKEY))
088bde77 3992 sha_mpint(&s, K);
d39f364a 3993 SHA_Bytes(&s, H, 20);
3994 SHA_Bytes(&s, keyspace, 20);
32874aea 3995 SHA_Final(&s, keyspace + 20);
d39f364a 3996}
3997
3998/*
7cca0d81 3999 * Handle the SSH2 transport layer.
e5574168 4000 */
51470298 4001static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
e5574168 4002{
51470298 4003 struct do_ssh2_transport_state {
4004 int nbits, pbits, warn;
4005 Bignum p, g, e, f, K;
4006 int kex_init_value, kex_reply_value;
4007 const struct ssh_mac **maclist;
4008 int nmacs;
4009 const struct ssh2_cipher *cscipher_tobe;
4010 const struct ssh2_cipher *sccipher_tobe;
4011 const struct ssh_mac *csmac_tobe;
4012 const struct ssh_mac *scmac_tobe;
4013 const struct ssh_compress *cscomp_tobe;
4014 const struct ssh_compress *sccomp_tobe;
4015 char *hostkeydata, *sigdata, *keystr, *fingerprint;
4016 int hostkeylen, siglen;
4017 void *hkey; /* actual host key */
4018 unsigned char exchange_hash[20];
4019 int n_preferred_ciphers;
4020 const struct ssh2_ciphers *preferred_ciphers[CIPHER_MAX];
4021 const struct ssh_compress *preferred_comp;
4022 int first_kex;
4023 };
4024 crState(do_ssh2_transport_state);
4025
4026 crBegin(ssh->do_ssh2_transport_crstate);
4027
4028 s->cscipher_tobe = s->sccipher_tobe = NULL;
4029 s->csmac_tobe = s->scmac_tobe = NULL;
4030 s->cscomp_tobe = s->sccomp_tobe = NULL;
4031
7cca0d81 4032 random_init();
51470298 4033 s->first_kex = 1;
e5574168 4034
51470298 4035 {
4036 int i;
4037 /*
4038 * Set up the preferred ciphers. (NULL => warn below here)
4039 */
4040 s->n_preferred_ciphers = 0;
4041 for (i = 0; i < CIPHER_MAX; i++) {
86916870 4042 switch (ssh->cfg.ssh_cipherlist[i]) {
51470298 4043 case CIPHER_BLOWFISH:
4044 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_blowfish;
4045 break;
4046 case CIPHER_DES:
86916870 4047 if (ssh->cfg.ssh2_des_cbc) {
51470298 4048 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_des;
4049 }
4050 break;
4051 case CIPHER_3DES:
4052 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_3des;
4053 break;
4054 case CIPHER_AES:
4055 s->preferred_ciphers[s->n_preferred_ciphers++] = &ssh2_aes;
4056 break;
4057 case CIPHER_WARN:
4058 /* Flag for later. Don't bother if it's the last in
4059 * the list. */
4060 if (i < CIPHER_MAX - 1) {
4061 s->preferred_ciphers[s->n_preferred_ciphers++] = NULL;
4062 }
4063 break;
ca20bfcf 4064 }
ca20bfcf 4065 }
5e8358ad 4066 }
ca20bfcf 4067
4068 /*
4069 * Set up preferred compression.
4070 */
86916870 4071 if (ssh->cfg.compression)
51470298 4072 s->preferred_comp = &ssh_zlib;
4ba9b64b 4073 else
51470298 4074 s->preferred_comp = &ssh_comp_none;
5e8358ad 4075
7591b9ff 4076 /*
4077 * Be prepared to work around the buggy MAC problem.
4078 */
51470298 4079 if (ssh->remote_bugs & BUG_SSH2_HMAC)
4080 s->maclist = buggymacs, s->nmacs = lenof(buggymacs);
7591b9ff 4081 else
51470298 4082 s->maclist = macs, s->nmacs = lenof(macs);
7591b9ff 4083
32874aea 4084 begin_key_exchange:
51470298 4085 {
4086 int i, j, cipherstr_started;
4087
4088 /*
4089 * Construct and send our key exchange packet.
4090 */
4091 ssh2_pkt_init(ssh, SSH2_MSG_KEXINIT);
4092 for (i = 0; i < 16; i++)
4093 ssh2_pkt_addbyte(ssh, (unsigned char) random_byte());
4094 /* List key exchange algorithms. */
4095 ssh2_pkt_addstring_start(ssh);
4096 for (i = 0; i < lenof(kex_algs); i++) {
4097 if (kex_algs[i] == &ssh_diffiehellman_gex &&
4098 (ssh->remote_bugs & BUG_SSH2_DH_GEX))
4099 continue;
4100 ssh2_pkt_addstring_str(ssh, kex_algs[i]->name);
4101 if (i < lenof(kex_algs) - 1)
4102 ssh2_pkt_addstring_str(ssh, ",");
32874aea 4103 }
51470298 4104 /* List server host key algorithms. */
4105 ssh2_pkt_addstring_start(ssh);
4106 for (i = 0; i < lenof(hostkey_algs); i++) {
4107 ssh2_pkt_addstring_str(ssh, hostkey_algs[i]->name);
4108 if (i < lenof(hostkey_algs) - 1)
4109 ssh2_pkt_addstring_str(ssh, ",");
32874aea 4110 }
51470298 4111 /* List client->server encryption algorithms. */
4112 ssh2_pkt_addstring_start(ssh);
4113 cipherstr_started = 0;
4114 for (i = 0; i < s->n_preferred_ciphers; i++) {
4115 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4116 if (!c) continue; /* warning flag */
4117 for (j = 0; j < c->nciphers; j++) {
4118 if (cipherstr_started)
4119 ssh2_pkt_addstring_str(ssh, ",");
4120 ssh2_pkt_addstring_str(ssh, c->list[j]->name);
4121 cipherstr_started = 1;
4122 }
4123 }
4124 /* List server->client encryption algorithms. */
4125 ssh2_pkt_addstring_start(ssh);
4126 cipherstr_started = 0;
4127 for (i = 0; i < s->n_preferred_ciphers; i++) {
4128 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4129 if (!c) continue; /* warning flag */
4130 for (j = 0; j < c->nciphers; j++) {
4131 if (cipherstr_started)
4132 ssh2_pkt_addstring_str(ssh, ",");
4133 ssh2_pkt_addstring_str(ssh, c->list[j]->name);
4134 cipherstr_started = 1;
4135 }
4136 }
4137 /* List client->server MAC algorithms. */
4138 ssh2_pkt_addstring_start(ssh);
4139 for (i = 0; i < s->nmacs; i++) {
4140 ssh2_pkt_addstring_str(ssh, s->maclist[i]->name);
4141 if (i < s->nmacs - 1)
4142 ssh2_pkt_addstring_str(ssh, ",");
4143 }
4144 /* List server->client MAC algorithms. */
4145 ssh2_pkt_addstring_start(ssh);
4146 for (i = 0; i < s->nmacs; i++) {
4147 ssh2_pkt_addstring_str(ssh, s->maclist[i]->name);
4148 if (i < s->nmacs - 1)
4149 ssh2_pkt_addstring_str(ssh, ",");
4150 }
4151 /* List client->server compression algorithms. */
4152 ssh2_pkt_addstring_start(ssh);
f6e0abe2 4153 assert(lenof(compressions) > 1);
4154 ssh2_pkt_addstring_str(ssh, s->preferred_comp->name);
4155 for (i = 0; i < lenof(compressions); i++) {
4156 const struct ssh_compress *c = compressions[i];
4157 if (c != s->preferred_comp) {
51470298 4158 ssh2_pkt_addstring_str(ssh, ",");
f6e0abe2 4159 ssh2_pkt_addstring_str(ssh, c->name);
4160 }
51470298 4161 }
4162 /* List server->client compression algorithms. */
4163 ssh2_pkt_addstring_start(ssh);
f6e0abe2 4164 assert(lenof(compressions) > 1);
4165 ssh2_pkt_addstring_str(ssh, s->preferred_comp->name);
4166 for (i = 0; i < lenof(compressions); i++) {
4167 const struct ssh_compress *c = compressions[i];
4168 if (c != s->preferred_comp) {
51470298 4169 ssh2_pkt_addstring_str(ssh, ",");
f6e0abe2 4170 ssh2_pkt_addstring_str(ssh, c->name);
4171 }
51470298 4172 }
4173 /* List client->server languages. Empty list. */
4174 ssh2_pkt_addstring_start(ssh);
4175 /* List server->client languages. Empty list. */
4176 ssh2_pkt_addstring_start(ssh);
4177 /* First KEX packet does _not_ follow, because we're not that brave. */
4178 ssh2_pkt_addbool(ssh, FALSE);
4179 /* Reserved. */
4180 ssh2_pkt_adduint32(ssh, 0);
e5574168 4181 }
0db56f73 4182
51470298 4183 ssh->exhash = ssh->exhashbase;
4184 sha_string(&ssh->exhash, ssh->pktout.data + 5, ssh->pktout.length - 5);
0db56f73 4185
51470298 4186 ssh2_pkt_send(ssh);
e5574168 4187
32874aea 4188 if (!ispkt)
4189 crWaitUntil(ispkt);
57356d63 4190 if (ssh->pktin.length > 5)
4191 sha_string(&ssh->exhash, ssh->pktin.data + 5, ssh->pktin.length - 5);
e5574168 4192
4193 /*
4194 * Now examine the other side's KEXINIT to see what we're up
4195 * to.
4196 */
51470298 4197 {
4198 char *str;
4199 int i, j, len;
4200
4201 if (ssh->pktin.type != SSH2_MSG_KEXINIT) {
6b5cf8b4 4202 bombout(("expected key exchange packet from server"));
7ffdbc1a 4203 crStop(0);
32874aea 4204 }
51470298 4205 ssh->kex = NULL;
4206 ssh->hostkey = NULL;
4207 s->cscipher_tobe = NULL;
4208 s->sccipher_tobe = NULL;
4209 s->csmac_tobe = NULL;
4210 s->scmac_tobe = NULL;
4211 s->cscomp_tobe = NULL;
4212 s->sccomp_tobe = NULL;
4213 ssh->pktin.savedpos += 16; /* skip garbage cookie */
0016d70b 4214 ssh_pkt_getstring(ssh, &str, &len); /* key exchange algorithms */
51470298 4215 for (i = 0; i < lenof(kex_algs); i++) {
4216 if (kex_algs[i] == &ssh_diffiehellman_gex &&
4217 (ssh->remote_bugs & BUG_SSH2_DH_GEX))
4218 continue;
4219 if (in_commasep_string(kex_algs[i]->name, str, len)) {
4220 ssh->kex = kex_algs[i];
4221 break;
4222 }
32874aea 4223 }
0016d70b 4224 ssh_pkt_getstring(ssh, &str, &len); /* host key algorithms */
51470298 4225 for (i = 0; i < lenof(hostkey_algs); i++) {
4226 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
4227 ssh->hostkey = hostkey_algs[i];
4228 break;
4229 }
4230 }
0016d70b 4231 ssh_pkt_getstring(ssh, &str, &len); /* client->server cipher */
51470298 4232 s->warn = 0;
4233 for (i = 0; i < s->n_preferred_ciphers; i++) {
4234 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4235 if (!c) {
4236 s->warn = 1;
4237 } else {
4238 for (j = 0; j < c->nciphers; j++) {
4239 if (in_commasep_string(c->list[j]->name, str, len)) {
4240 s->cscipher_tobe = c->list[j];
4241 break;
4242 }
ca20bfcf 4243 }
32874aea 4244 }
51470298 4245 if (s->cscipher_tobe) {
4246 if (s->warn)
a8327734 4247 askcipher(ssh->frontend, s->cscipher_tobe->name, 1);
51470298 4248 break;
4249 }
32874aea 4250 }
51470298 4251 if (!s->cscipher_tobe) {
6b5cf8b4 4252 bombout(("Couldn't agree a client-to-server cipher (available: %s)",
57356d63 4253 str ? str : "(null)"));
7ffdbc1a 4254 crStop(0);
ca20bfcf 4255 }
0ef8f407 4256
0016d70b 4257 ssh_pkt_getstring(ssh, &str, &len); /* server->client cipher */
51470298 4258 s->warn = 0;
4259 for (i = 0; i < s->n_preferred_ciphers; i++) {
4260 const struct ssh2_ciphers *c = s->preferred_ciphers[i];
4261 if (!c) {
4262 s->warn = 1;
4263 } else {
4264 for (j = 0; j < c->nciphers; j++) {
4265 if (in_commasep_string(c->list[j]->name, str, len)) {
4266 s->sccipher_tobe = c->list[j];
4267 break;
4268 }
ca20bfcf 4269 }
32874aea 4270 }
51470298 4271 if (s->sccipher_tobe) {
4272 if (s->warn)
a8327734 4273 askcipher(ssh->frontend, s->sccipher_tobe->name, 2);
51470298 4274 break;
4275 }
32874aea 4276 }
51470298 4277 if (!s->sccipher_tobe) {
6b5cf8b4 4278 bombout(("Couldn't agree a server-to-client cipher (available: %s)",
57356d63 4279 str ? str : "(null)"));
7ffdbc1a 4280 crStop(0);
ca20bfcf 4281 }
0ef8f407 4282
0016d70b 4283 ssh_pkt_getstring(ssh, &str, &len); /* client->server mac */
51470298 4284 for (i = 0; i < s->nmacs; i++) {
4285 if (in_commasep_string(s->maclist[i]->name, str, len)) {
4286 s->csmac_tobe = s->maclist[i];
4287 break;
4288 }
32874aea 4289 }
0016d70b 4290 ssh_pkt_getstring(ssh, &str, &len); /* server->client mac */
51470298 4291 for (i = 0; i < s->nmacs; i++) {
4292 if (in_commasep_string(s->maclist[i]->name, str, len)) {
4293 s->scmac_tobe = s->maclist[i];
4294 break;
4295 }
32874aea 4296 }
0016d70b 4297 ssh_pkt_getstring(ssh, &str, &len); /* client->server compression */
51470298 4298 for (i = 0; i < lenof(compressions) + 1; i++) {
4299 const struct ssh_compress *c =
4300 i == 0 ? s->preferred_comp : compressions[i - 1];
4301 if (in_commasep_string(c->name, str, len)) {
4302 s->cscomp_tobe = c;
4303 break;
4304 }
32874aea 4305 }
0016d70b 4306 ssh_pkt_getstring(ssh, &str, &len); /* server->client compression */
51470298 4307 for (i = 0; i < lenof(compressions) + 1; i++) {
4308 const struct ssh_compress *c =
4309 i == 0 ? s->preferred_comp : compressions[i - 1];
4310 if (in_commasep_string(c->name, str, len)) {
4311 s->sccomp_tobe = c;
4312 break;
4313 }
32874aea 4314 }
e5574168 4315 }
e5574168 4316
4317 /*
7bd5a860 4318 * Work out the number of bits of key we will need from the key
4319 * exchange. We start with the maximum key length of either
4320 * cipher...
4321 */
4322 {
32874aea 4323 int csbits, scbits;
7bd5a860 4324
51470298 4325 csbits = s->cscipher_tobe->keylen;
4326 scbits = s->sccipher_tobe->keylen;
4327 s->nbits = (csbits > scbits ? csbits : scbits);
7bd5a860 4328 }
4329 /* The keys only have 160-bit entropy, since they're based on
4330 * a SHA-1 hash. So cap the key size at 160 bits. */
51470298 4331 if (s->nbits > 160)
4332 s->nbits = 160;
7bd5a860 4333
4334 /*
a92dd380 4335 * If we're doing Diffie-Hellman group exchange, start by
4336 * requesting a group.
e5574168 4337 */
51470298 4338 if (ssh->kex == &ssh_diffiehellman_gex) {
32874aea 4339 logevent("Doing Diffie-Hellman group exchange");
51470298 4340 ssh->pkt_ctx |= SSH2_PKTCTX_DHGEX;
32874aea 4341 /*
4342 * Work out how big a DH group we will need to allow that
4343 * much data.
7bd5a860 4344 */
51470298 4345 s->pbits = 512 << ((s->nbits - 1) / 64);
4346 ssh2_pkt_init(ssh, SSH2_MSG_KEX_DH_GEX_REQUEST);
4347 ssh2_pkt_adduint32(ssh, s->pbits);
4348 ssh2_pkt_send(ssh);
32874aea 4349
4350 crWaitUntil(ispkt);
51470298 4351 if (ssh->pktin.type != SSH2_MSG_KEX_DH_GEX_GROUP) {
6b5cf8b4 4352 bombout(("expected key exchange group packet from server"));
7ffdbc1a 4353 crStop(0);
32874aea 4354 }
51470298 4355 s->p = ssh2_pkt_getmp(ssh);
4356 s->g = ssh2_pkt_getmp(ssh);
27cd7fc2 4357 ssh->kex_ctx = dh_setup_group(s->p, s->g);
51470298 4358 s->kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
4359 s->kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY;
a92dd380 4360 } else {
51470298 4361 ssh->pkt_ctx |= SSH2_PKTCTX_DHGROUP1;
27cd7fc2 4362 ssh->kex_ctx = dh_setup_group1();
51470298 4363 s->kex_init_value = SSH2_MSG_KEXDH_INIT;
4364 s->kex_reply_value = SSH2_MSG_KEXDH_REPLY;
8d5de777 4365 }
e5574168 4366
a92dd380 4367 logevent("Doing Diffie-Hellman key exchange");
e5574168 4368 /*
a92dd380 4369 * Now generate and send e for Diffie-Hellman.
e5574168 4370 */
27cd7fc2 4371 s->e = dh_create_e(ssh->kex_ctx, s->nbits * 2);
51470298 4372 ssh2_pkt_init(ssh, s->kex_init_value);
4373 ssh2_pkt_addmp(ssh, s->e);
4374 ssh2_pkt_send(ssh);
e5574168 4375
4376 crWaitUntil(ispkt);
51470298 4377 if (ssh->pktin.type != s->kex_reply_value) {
6b5cf8b4 4378 bombout(("expected key exchange reply packet from server"));
7ffdbc1a 4379 crStop(0);
7cca0d81 4380 }
0016d70b 4381 ssh_pkt_getstring(ssh, &s->hostkeydata, &s->hostkeylen);
51470298 4382 s->f = ssh2_pkt_getmp(ssh);
0016d70b 4383 ssh_pkt_getstring(ssh, &s->sigdata, &s->siglen);
e5574168 4384
27cd7fc2 4385 s->K = dh_find_K(ssh->kex_ctx, s->f);
e5574168 4386
51470298 4387 sha_string(&ssh->exhash, s->hostkeydata, s->hostkeylen);
4388 if (ssh->kex == &ssh_diffiehellman_gex) {
4389 sha_uint32(&ssh->exhash, s->pbits);
4390 sha_mpint(&ssh->exhash, s->p);
4391 sha_mpint(&ssh->exhash, s->g);
a92dd380 4392 }
51470298 4393 sha_mpint(&ssh->exhash, s->e);
4394 sha_mpint(&ssh->exhash, s->f);
4395 sha_mpint(&ssh->exhash, s->K);
4396 SHA_Final(&ssh->exhash, s->exchange_hash);
e5574168 4397
27cd7fc2 4398 dh_cleanup(ssh->kex_ctx);
fabd1805 4399 ssh->kex_ctx = NULL;
3709bfe9 4400
7cca0d81 4401#if 0
765c4200 4402 debug(("Exchange hash is:\n"));
51470298 4403 dmemdump(s->exchange_hash, 20);
7cca0d81 4404#endif
4405
51470298 4406 s->hkey = ssh->hostkey->newkey(s->hostkeydata, s->hostkeylen);
4407 if (!s->hkey ||
4408 !ssh->hostkey->verifysig(s->hkey, s->sigdata, s->siglen,
d8baa528 4409 (char *)s->exchange_hash, 20)) {
6b5cf8b4 4410 bombout(("Server's host key did not match the signature supplied"));
7ffdbc1a 4411 crStop(0);
8d5de777 4412 }
e5574168 4413
4414 /*
7cca0d81 4415 * Authenticate remote host: verify host key. (We've already
4416 * checked the signature of the exchange hash.)
e5574168 4417 */
51470298 4418 s->keystr = ssh->hostkey->fmtkey(s->hkey);
4419 s->fingerprint = ssh->hostkey->fingerprint(s->hkey);
a8327734 4420 verify_ssh_host_key(ssh->frontend,
4421 ssh->savedhost, ssh->savedport, ssh->hostkey->keytype,
51470298 4422 s->keystr, s->fingerprint);
4423 if (s->first_kex) { /* don't bother logging this in rekeys */
5e0d7cb8 4424 logevent("Host key fingerprint is:");
51470298 4425 logevent(s->fingerprint);
5e0d7cb8 4426 }
51470298 4427 sfree(s->fingerprint);
4428 sfree(s->keystr);
4429 ssh->hostkey->freekey(s->hkey);
d39f364a 4430
4431 /*
7cca0d81 4432 * Send SSH2_MSG_NEWKEYS.
d39f364a 4433 */
51470298 4434 ssh2_pkt_init(ssh, SSH2_MSG_NEWKEYS);
4435 ssh2_pkt_send(ssh);
d39f364a 4436
4437 /*
8406eaf9 4438 * Expect SSH2_MSG_NEWKEYS from server.
4439 */
4440 crWaitUntil(ispkt);
51470298 4441 if (ssh->pktin.type != SSH2_MSG_NEWKEYS) {
6b5cf8b4 4442 bombout(("expected new-keys packet from server"));
7ffdbc1a 4443 crStop(0);
8406eaf9 4444 }
4445
4446 /*
d39f364a 4447 * Create and initialise session keys.
4448 */
371e569c 4449 if (ssh->cs_cipher_ctx)
4450 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
51470298 4451 ssh->cscipher = s->cscipher_tobe;
371e569c 4452 ssh->cs_cipher_ctx = ssh->cscipher->make_context();
e0e1a00d 4453
371e569c 4454 if (ssh->sc_cipher_ctx)
4455 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
51470298 4456 ssh->sccipher = s->sccipher_tobe;
371e569c 4457 ssh->sc_cipher_ctx = ssh->sccipher->make_context();
e0e1a00d 4458
4459 if (ssh->cs_mac_ctx)
4460 ssh->csmac->free_context(ssh->cs_mac_ctx);
51470298 4461 ssh->csmac = s->csmac_tobe;
e0e1a00d 4462 ssh->cs_mac_ctx = ssh->csmac->make_context();
4463
4464 if (ssh->sc_mac_ctx)
4465 ssh->scmac->free_context(ssh->sc_mac_ctx);
51470298 4466 ssh->scmac = s->scmac_tobe;
e0e1a00d 4467 ssh->sc_mac_ctx = ssh->scmac->make_context();
4468
5366aed8 4469 if (ssh->cs_comp_ctx)
4470 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
51470298 4471 ssh->cscomp = s->cscomp_tobe;
5366aed8 4472 ssh->cs_comp_ctx = ssh->cscomp->compress_init();
4473
4474 if (ssh->sc_comp_ctx)
4475 ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
51470298 4476 ssh->sccomp = s->sccomp_tobe;
5366aed8 4477 ssh->sc_comp_ctx = ssh->sccomp->decompress_init();
4478
d39f364a 4479 /*
5e0d7cb8 4480 * Set IVs after keys. Here we use the exchange hash from the
4481 * _first_ key exchange.
d39f364a 4482 */
51470298 4483 {
4484 unsigned char keyspace[40];
4485 if (s->first_kex)
4486 memcpy(ssh->v2_session_id, s->exchange_hash,
4487 sizeof(s->exchange_hash));
4488 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'C',keyspace);
371e569c 4489 ssh->cscipher->setkey(ssh->cs_cipher_ctx, keyspace);
51470298 4490 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'D',keyspace);
371e569c 4491 ssh->sccipher->setkey(ssh->sc_cipher_ctx, keyspace);
51470298 4492 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'A',keyspace);
371e569c 4493 ssh->cscipher->setiv(ssh->cs_cipher_ctx, keyspace);
51470298 4494 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'B',keyspace);
371e569c 4495 ssh->sccipher->setiv(ssh->sc_cipher_ctx, keyspace);
51470298 4496 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'E',keyspace);
e0e1a00d 4497 ssh->csmac->setkey(ssh->cs_mac_ctx, keyspace);
51470298 4498 ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'F',keyspace);
e0e1a00d 4499 ssh->scmac->setkey(ssh->sc_mac_ctx, keyspace);
51470298 4500 }
57356d63 4501 logeventf(ssh, "Initialised %.200s client->server encryption",
4502 ssh->cscipher->text_name);
4503 logeventf(ssh, "Initialised %.200s server->client encryption",
4504 ssh->sccipher->text_name);
6c135243 4505 logeventf(ssh, "Initialised %.200s client->server MAC algorithm",
4506 ssh->csmac->text_name);
4507 logeventf(ssh, "Initialised %.200s server->client MAC algorithm",
4508 ssh->scmac->text_name);
57356d63 4509 if (ssh->cscomp->text_name)
4510 logeventf(ssh, "Initialised %s compression",
4511 ssh->cscomp->text_name);
4512 if (ssh->sccomp->text_name)
4513 logeventf(ssh, "Initialised %s decompression",
4514 ssh->sccomp->text_name);
679539d7 4515 freebn(s->f);
679539d7 4516 freebn(s->K);
b3949e7e 4517 if (ssh->kex == &ssh_diffiehellman_gex) {
4518 freebn(s->g);
4519 freebn(s->p);
4520 }
d39f364a 4521
033b4cef 4522 /*
0db56f73 4523 * If this is the first key exchange phase, we must pass the
4524 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
4525 * wants to see it but because it will need time to initialise
4526 * itself before it sees an actual packet. In subsequent key
4527 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
4528 * it would only confuse the layer above.
4529 */
51470298 4530 if (!s->first_kex) {
32874aea 4531 crReturn(0);
0db56f73 4532 }
51470298 4533 s->first_kex = 0;
0db56f73 4534
4535 /*
7cca0d81 4536 * Now we're encrypting. Begin returning 1 to the protocol main
4537 * function so that other things can run on top of the
4538 * transport. If we ever see a KEXINIT, we must go back to the
4539 * start.
033b4cef 4540 */
51470298 4541 while (!(ispkt && ssh->pktin.type == SSH2_MSG_KEXINIT)) {
32874aea 4542 crReturn(1);
e96adf72 4543 }
5e0d7cb8 4544 logevent("Server initiated key re-exchange");
7cca0d81 4545 goto begin_key_exchange;
e5574168 4546
4547 crFinish(1);
4548}
4549
7cca0d81 4550/*
783415f8 4551 * Add data to an SSH2 channel output buffer.
4552 */
32874aea 4553static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
4554 int len)
4555{
5471d09a 4556 bufchain_add(&c->v.v2.outbuffer, buf, len);
783415f8 4557}
4558
4559/*
4560 * Attempt to send data on an SSH2 channel.
4561 */
5471d09a 4562static int ssh2_try_send(struct ssh_channel *c)
32874aea 4563{
51470298 4564 Ssh ssh = c->ssh;
4565
5471d09a 4566 while (c->v.v2.remwindow > 0 && bufchain_size(&c->v.v2.outbuffer) > 0) {
4567 int len;
4568 void *data;
4569 bufchain_prefix(&c->v.v2.outbuffer, &data, &len);
4570 if ((unsigned)len > c->v.v2.remwindow)
4571 len = c->v.v2.remwindow;
4572 if ((unsigned)len > c->v.v2.remmaxpkt)
4573 len = c->v.v2.remmaxpkt;
51470298 4574 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_DATA);
4575 ssh2_pkt_adduint32(ssh, c->remoteid);
4576 ssh2_pkt_addstring_start(ssh);
4577 ssh2_pkt_addstring_data(ssh, data, len);
4578 ssh2_pkt_send(ssh);
5471d09a 4579 bufchain_consume(&c->v.v2.outbuffer, len);
4580 c->v.v2.remwindow -= len;
4581 }
4582
4583 /*
4584 * After having sent as much data as we can, return the amount
4585 * still buffered.
4586 */
4587 return bufchain_size(&c->v.v2.outbuffer);
4588}
4589
4590/*
4591 * Potentially enlarge the window on an SSH2 channel.
4592 */
4593static void ssh2_set_window(struct ssh_channel *c, unsigned newwin)
4594{
51470298 4595 Ssh ssh = c->ssh;
4596
6b69f42e 4597 /*
4598 * Never send WINDOW_ADJUST for a channel that the remote side
4599 * already thinks it's closed; there's no point, since it won't
4600 * be sending any more data anyway.
4601 */
4602 if (c->closes != 0)
4603 return;
4604
5471d09a 4605 if (newwin > c->v.v2.locwindow) {
51470298 4606 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST);
4607 ssh2_pkt_adduint32(ssh, c->remoteid);
4608 ssh2_pkt_adduint32(ssh, newwin - c->v.v2.locwindow);
4609 ssh2_pkt_send(ssh);
5471d09a 4610 c->v.v2.locwindow = newwin;
783415f8 4611 }
4612}
4613
4614/*
7cca0d81 4615 * Handle the SSH2 userauth and connection layers.
4616 */
51470298 4617static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
7cca0d81 4618{
51470298 4619 struct do_ssh2_authconn_state {
4620 enum {
4621 AUTH_INVALID, AUTH_PUBLICKEY_AGENT, AUTH_PUBLICKEY_FILE,
4622 AUTH_PASSWORD,
4623 AUTH_KEYBOARD_INTERACTIVE
4624 } method;
4625 enum {
4626 AUTH_TYPE_NONE,
4627 AUTH_TYPE_PUBLICKEY,
4628 AUTH_TYPE_PUBLICKEY_OFFER_LOUD,
4629 AUTH_TYPE_PUBLICKEY_OFFER_QUIET,
4630 AUTH_TYPE_PASSWORD,
4631 AUTH_TYPE_KEYBOARD_INTERACTIVE,
4632 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
4633 } type;
4634 int gotit, need_pw, can_pubkey, can_passwd, can_keyb_inter;
4635 int tried_pubkey_config, tried_agent, tried_keyb_inter;
4636 int kbd_inter_running;
4637 int we_are_in;
4638 int num_prompts, curr_prompt, echo;
4639 char username[100];
4640 int got_username;
85fdbe25 4641 char pwprompt[512];
51470298 4642 char password[100];
4643 void *publickey_blob;
4644 int publickey_bloblen;
4645 unsigned char request[5], *response, *p;
4646 int responselen;
4647 int keyi, nkeys;
4648 int authed;
4649 char *pkblob, *alg, *commentp;
4650 int pklen, alglen, commentlen;
4651 int siglen, retlen, len;
4652 char *q, *agentreq, *ret;
4653 int try_send;
4654 };
4655 crState(do_ssh2_authconn_state);
4656
4657 crBegin(ssh->do_ssh2_authconn_crstate);
e5574168 4658
7cca0d81 4659 /*
4660 * Request userauth protocol, and await a response to it.
4661 */
51470298 4662 ssh2_pkt_init(ssh, SSH2_MSG_SERVICE_REQUEST);
4663 ssh2_pkt_addstring(ssh, "ssh-userauth");
4664 ssh2_pkt_send(ssh);
7cca0d81 4665 crWaitUntilV(ispkt);
51470298 4666 if (ssh->pktin.type != SSH2_MSG_SERVICE_ACCEPT) {
6b5cf8b4 4667 bombout(("Server refused user authentication protocol"));
7ffdbc1a 4668 crStopV;
8d5de777 4669 }
7cca0d81 4670
4671 /*
1408a877 4672 * We repeat this whole loop, including the username prompt,
4673 * until we manage a successful authentication. If the user
51470298 4674 * types the wrong _password_, they can be sent back to the
4675 * beginning to try another username, if this is configured on.
4676 * (If they specify a username in the config, they are never
4677 * asked, even if they do give a wrong password.)
1408a877 4678 *
4679 * I think this best serves the needs of
4680 *
4681 * - the people who have no configuration, no keys, and just
4682 * want to try repeated (username,password) pairs until they
4683 * type both correctly
4684 *
4685 * - people who have keys and configuration but occasionally
4686 * need to fall back to passwords
4687 *
4688 * - people with a key held in Pageant, who might not have
4689 * logged in to a particular machine before; so they want to
4690 * type a username, and then _either_ their key will be
4691 * accepted, _or_ they will type a password. If they mistype
4692 * the username they will want to be able to get back and
4693 * retype it!
7cca0d81 4694 */
51470298 4695 s->username[0] = '\0';
4696 s->got_username = FALSE;
1408a877 4697 do {
1408a877 4698 /*
4699 * Get a username.
4700 */
86916870 4701 if (s->got_username && !ssh->cfg.change_username) {
5bb641e1 4702 /*
4703 * We got a username last time round this loop, and
4704 * with change_username turned off we don't try to get
4705 * it again.
4706 */
86916870 4707 } else if ((flags & FLAG_INTERACTIVE) && !*ssh->cfg.username) {
c0a81592 4708 if (ssh_get_line && !ssh_getline_pw_only) {
32874aea 4709 if (!ssh_get_line("login as: ",
51470298 4710 s->username, sizeof(s->username), FALSE)) {
32874aea 4711 /*
4712 * get_line failed to get a username.
4713 * Terminate.
4714 */
4715 logevent("No username provided. Abandoning session.");
3bb2f322 4716 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 4717 crStopV;
32874aea 4718 }
4719 } else {
51470298 4720 int ret; /* need not be saved across crReturn */
4721 c_write_str(ssh, "login as: ");
4722 ssh->send_ok = 1;
4723 setup_userpass_input(ssh, s->username, sizeof(s->username), 1);
0405e71f 4724 do {
32874aea 4725 crWaitUntilV(!ispkt);
51470298 4726 ret = process_userpass_input(ssh, in, inlen);
0405e71f 4727 } while (ret == 0);
4728 if (ret < 0)
4729 cleanup_exit(0);
4ca0c9d1 4730 c_write_str(ssh, "\r\n");
32874aea 4731 }
51470298 4732 s->username[strcspn(s->username, "\n\r")] = '\0';
7cca0d81 4733 } else {
57356d63 4734 char *stuff;
86916870 4735 strncpy(s->username, ssh->cfg.username, sizeof(s->username));
51470298 4736 s->username[sizeof(s->username)-1] = '\0';
65a22376 4737 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
57356d63 4738 stuff = dupprintf("Using username \"%s\".\r\n", s->username);
51470298 4739 c_write_str(ssh, stuff);
57356d63 4740 sfree(stuff);
7cca0d81 4741 }
4742 }
51470298 4743 s->got_username = TRUE;
7cca0d81 4744
65a22376 4745 /*
1408a877 4746 * Send an authentication request using method "none": (a)
4747 * just in case it succeeds, and (b) so that we know what
4748 * authentication methods we can usefully try next.
65a22376 4749 */
51470298 4750 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4751
4752 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
4753 ssh2_pkt_addstring(ssh, s->username);
4754 ssh2_pkt_addstring(ssh, "ssh-connection");/* service requested */
4755 ssh2_pkt_addstring(ssh, "none"); /* method */
4756 ssh2_pkt_send(ssh);
4757 s->type = AUTH_TYPE_NONE;
4758 s->gotit = FALSE;
4759 s->we_are_in = FALSE;
4760
4761 s->tried_pubkey_config = FALSE;
4762 s->tried_agent = FALSE;
4763 s->tried_keyb_inter = FALSE;
4764 s->kbd_inter_running = FALSE;
86916870 4765 /* Load the pub half of ssh->cfg.keyfile so we notice if it's in Pageant */
9a30e26b 4766 if (!filename_is_null(ssh->cfg.keyfile)) {
231ee168 4767 int keytype;
6c6d9ed9 4768 logeventf(ssh, "Reading private key file \"%.150s\"",
4769 filename_to_str(&ssh->cfg.keyfile));
9a30e26b 4770 keytype = key_type(&ssh->cfg.keyfile);
51470298 4771 if (keytype == SSH_KEYTYPE_SSH2) {
4772 s->publickey_blob =
9a30e26b 4773 ssh2_userkey_loadpub(&ssh->cfg.keyfile, NULL,
222d54dc 4774 &s->publickey_bloblen, NULL);
51470298 4775 } else {
57356d63 4776 char *msgbuf;
c2ad7d0d 4777 logeventf(ssh, "Unable to use this key file (%s)",
a8327734 4778 key_type_to_str(keytype));
57356d63 4779 msgbuf = dupprintf("Unable to use key file \"%.150s\""
6c6d9ed9 4780 " (%s)\r\n",
4781 filename_to_str(&ssh->cfg.keyfile),
57356d63 4782 key_type_to_str(keytype));
51470298 4783 c_write_str(ssh, msgbuf);
57356d63 4784 sfree(msgbuf);
51470298 4785 s->publickey_blob = NULL;
231ee168 4786 }
396778f1 4787 } else
51470298 4788 s->publickey_blob = NULL;
65a22376 4789
1408a877 4790 while (1) {
4791 /*
4792 * Wait for the result of the last authentication request.
4793 */
51470298 4794 if (!s->gotit)
1408a877 4795 crWaitUntilV(ispkt);
51470298 4796 while (ssh->pktin.type == SSH2_MSG_USERAUTH_BANNER) {
32874aea 4797 char *banner;
4798 int size;
4799 /*
4800 * Don't show the banner if we're operating in
4801 * non-verbose non-interactive mode. (It's probably
4802 * a script, which means nobody will read the
4803 * banner _anyway_, and moreover the printing of
4804 * the banner will screw up processing on the
4805 * output of (say) plink.)
4806 */
4807 if (flags & (FLAG_VERBOSE | FLAG_INTERACTIVE)) {
0016d70b 4808 ssh_pkt_getstring(ssh, &banner, &size);
32874aea 4809 if (banner)
51470298 4810 c_write_untrusted(ssh, banner, size);
32874aea 4811 }
1408a877 4812 crWaitUntilV(ispkt);
4813 }
51470298 4814 if (ssh->pktin.type == SSH2_MSG_USERAUTH_SUCCESS) {
1408a877 4815 logevent("Access granted");
51470298 4816 s->we_are_in = TRUE;
1408a877 4817 break;
4818 }
65a22376 4819
51470298 4820 if (s->kbd_inter_running &&
4821 ssh->pktin.type == SSH2_MSG_USERAUTH_INFO_REQUEST) {
b3186d64 4822 /*
45068b27 4823 * This is either a further set-of-prompts packet
4824 * in keyboard-interactive authentication, or it's
4825 * the same one and we came back here with `gotit'
4826 * set. In the former case, we must reset the
4827 * curr_prompt variable.
b3186d64 4828 */
51470298 4829 if (!s->gotit)
4830 s->curr_prompt = 0;
4831 } else if (ssh->pktin.type != SSH2_MSG_USERAUTH_FAILURE) {
6b5cf8b4 4832 bombout(("Strange packet received during authentication: type %d",
51470298 4833 ssh->pktin.type));
7ffdbc1a 4834 crStopV;
65a22376 4835 }
4836
51470298 4837 s->gotit = FALSE;
65a22376 4838
1408a877 4839 /*
4840 * OK, we're now sitting on a USERAUTH_FAILURE message, so
4841 * we can look at the string in it and know what we can
4842 * helpfully try next.
4843 */
51470298 4844 if (ssh->pktin.type == SSH2_MSG_USERAUTH_FAILURE) {
1408a877 4845 char *methods;
4846 int methlen;
0016d70b 4847 ssh_pkt_getstring(ssh, &methods, &methlen);
51470298 4848 s->kbd_inter_running = FALSE;
4849 if (!ssh2_pkt_getbool(ssh)) {
1408a877 4850 /*
4851 * We have received an unequivocal Access
4852 * Denied. This can translate to a variety of
4853 * messages:
4854 *
4855 * - if we'd just tried "none" authentication,
4856 * it's not worth printing anything at all
4857 *
4858 * - if we'd just tried a public key _offer_,
4859 * the message should be "Server refused our
4860 * key" (or no message at all if the key
4861 * came from Pageant)
4862 *
4863 * - if we'd just tried anything else, the
4864 * message really should be "Access denied".
4865 *
4866 * Additionally, if we'd just tried password
4867 * authentication, we should break out of this
4868 * whole loop so as to go back to the username
4869 * prompt.
4870 */
51470298 4871 if (s->type == AUTH_TYPE_NONE) {
1408a877 4872 /* do nothing */
51470298 4873 } else if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD ||
4874 s->type == AUTH_TYPE_PUBLICKEY_OFFER_QUIET) {
4875 if (s->type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD)
4876 c_write_str(ssh, "Server refused our key\r\n");
1408a877 4877 logevent("Server refused public key");
51470298 4878 } else if (s->type==AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET) {
4bdf7c46 4879 /* server declined keyboard-interactive; ignore */
1408a877 4880 } else {
51470298 4881 c_write_str(ssh, "Access denied\r\n");
1408a877 4882 logevent("Access denied");
51470298 4883 if (s->type == AUTH_TYPE_PASSWORD) {
4884 s->we_are_in = FALSE;
1408a877 4885 break;
4886 }
4887 }
4888 } else {
51470298 4889 c_write_str(ssh, "Further authentication required\r\n");
1408a877 4890 logevent("Further authentication required");
4891 }
65a22376 4892
51470298 4893 s->can_pubkey =
32874aea 4894 in_commasep_string("publickey", methods, methlen);
51470298 4895 s->can_passwd =
32874aea 4896 in_commasep_string("password", methods, methlen);
86916870 4897 s->can_keyb_inter = ssh->cfg.try_ki_auth &&
761187b6 4898 in_commasep_string("keyboard-interactive", methods, methlen);
1408a877 4899 }
65a22376 4900
51470298 4901 s->method = 0;
4902 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
954a9540 4903 s->need_pw = FALSE;
65a22376 4904
0405e71f 4905 /*
4906 * Most password/passphrase prompts will be
4907 * non-echoing, so we set this to 0 by default.
4908 * Exception is that some keyboard-interactive prompts
4909 * can be echoing, in which case we'll set this to 1.
4910 */
51470298 4911 s->echo = 0;
0405e71f 4912
51470298 4913 if (!s->method && s->can_pubkey &&
4914 agent_exists() && !s->tried_agent) {
1983e559 4915 /*
4916 * Attempt public-key authentication using Pageant.
4917 */
1983e559 4918 void *r;
51470298 4919 s->authed = FALSE;
1983e559 4920
51470298 4921 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4922 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
00db133f 4923
51470298 4924 s->tried_agent = TRUE;
1983e559 4925
4926 logevent("Pageant is running. Requesting keys.");
4927
4928 /* Request the keys held by the agent. */
51470298 4929 PUT_32BIT(s->request, 1);
4930 s->request[4] = SSH2_AGENTC_REQUEST_IDENTITIES;
839f10db 4931 if (!agent_query(s->request, 5, &r, &s->responselen,
4932 ssh_agent_callback, ssh)) {
4933 do {
4934 crReturnV;
4935 if (ispkt) {
4936 bombout(("Unexpected data from server while"
4937 " waiting for agent response"));
4938 crStopV;
4939 }
4940 } while (ispkt || inlen > 0);
4941 r = ssh->agent_response;
4942 s->responselen = ssh->agent_response_len;
4943 }
51470298 4944 s->response = (unsigned char *) r;
4945 if (s->response && s->responselen >= 5 &&
4946 s->response[4] == SSH2_AGENT_IDENTITIES_ANSWER) {
4947 s->p = s->response + 5;
4948 s->nkeys = GET_32BIT(s->p);
4949 s->p += 4;
32874aea 4950 {
4951 char buf[64];
51470298 4952 sprintf(buf, "Pageant has %d SSH2 keys", s->nkeys);
32874aea 4953 logevent(buf);
4954 }
51470298 4955 for (s->keyi = 0; s->keyi < s->nkeys; s->keyi++) {
2d466ffd 4956 void *vret;
1983e559 4957
32874aea 4958 {
4959 char buf[64];
51470298 4960 sprintf(buf, "Trying Pageant key #%d", s->keyi);
32874aea 4961 logevent(buf);
4962 }
51470298 4963 s->pklen = GET_32BIT(s->p);
4964 s->p += 4;
4965 if (s->publickey_blob &&
4966 s->pklen == s->publickey_bloblen &&
4967 !memcmp(s->p, s->publickey_blob,
4968 s->publickey_bloblen)) {
396778f1 4969 logevent("This key matches configured key file");
51470298 4970 s->tried_pubkey_config = 1;
396778f1 4971 }
d8baa528 4972 s->pkblob = (char *)s->p;
51470298 4973 s->p += s->pklen;
4974 s->alglen = GET_32BIT(s->pkblob);
4975 s->alg = s->pkblob + 4;
4976 s->commentlen = GET_32BIT(s->p);
4977 s->p += 4;
d8baa528 4978 s->commentp = (char *)s->p;
51470298 4979 s->p += s->commentlen;
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, FALSE); /* no signature included */
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 ssh2_pkt_send(ssh);
1983e559 4990
4991 crWaitUntilV(ispkt);
51470298 4992 if (ssh->pktin.type != SSH2_MSG_USERAUTH_PK_OK) {
1983e559 4993 logevent("Key refused");
4994 continue;
4995 }
4996
32874aea 4997 if (flags & FLAG_VERBOSE) {
51470298 4998 c_write_str(ssh, "Authenticating with "
4999 "public key \"");
5000 c_write(ssh, s->commentp, s->commentlen);
5001 c_write_str(ssh, "\" from agent\r\n");
32874aea 5002 }
1983e559 5003
5004 /*
5005 * Server is willing to accept the key.
5006 * Construct a SIGN_REQUEST.
5007 */
51470298 5008 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
5009 ssh2_pkt_addstring(ssh, s->username);
5010 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
5011 ssh2_pkt_addstring(ssh, "publickey"); /* method */
5012 ssh2_pkt_addbool(ssh, TRUE);
5013 ssh2_pkt_addstring_start(ssh);
5014 ssh2_pkt_addstring_data(ssh, s->alg, s->alglen);
5015 ssh2_pkt_addstring_start(ssh);
5016 ssh2_pkt_addstring_data(ssh, s->pkblob, s->pklen);
5017
5018 s->siglen = ssh->pktout.length - 5 + 4 + 20;
dda87a28 5019 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
5020 s->siglen -= 4;
51470298 5021 s->len = 1; /* message type */
5022 s->len += 4 + s->pklen; /* key blob */
5023 s->len += 4 + s->siglen; /* data to sign */
5024 s->len += 4; /* flags */
3d88e64d 5025 s->agentreq = snewn(4 + s->len, char);
51470298 5026 PUT_32BIT(s->agentreq, s->len);
5027 s->q = s->agentreq + 4;
5028 *s->q++ = SSH2_AGENTC_SIGN_REQUEST;
5029 PUT_32BIT(s->q, s->pklen);
5030 s->q += 4;
5031 memcpy(s->q, s->pkblob, s->pklen);
5032 s->q += s->pklen;
5033 PUT_32BIT(s->q, s->siglen);
5034 s->q += 4;
1983e559 5035 /* Now the data to be signed... */
dda87a28 5036 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
5037 PUT_32BIT(s->q, 20);
5038 s->q += 4;
5039 }
51470298 5040 memcpy(s->q, ssh->v2_session_id, 20);
5041 s->q += 20;
5042 memcpy(s->q, ssh->pktout.data + 5,
5043 ssh->pktout.length - 5);
5044 s->q += ssh->pktout.length - 5;
1983e559 5045 /* And finally the (zero) flags word. */
51470298 5046 PUT_32BIT(s->q, 0);
839f10db 5047 if (!agent_query(s->agentreq, s->len + 4,
5048 &vret, &s->retlen,
5049 ssh_agent_callback, ssh)) {
5050 do {
5051 crReturnV;
5052 if (ispkt) {
5053 bombout(("Unexpected data from server"
5054 " while waiting for agent"
5055 " response"));
5056 crStopV;
5057 }
5058 } while (ispkt || inlen > 0);
5059 vret = ssh->agent_response;
5060 s->retlen = ssh->agent_response_len;
5061 }
51470298 5062 s->ret = vret;
5063 sfree(s->agentreq);
5064 if (s->ret) {
5065 if (s->ret[4] == SSH2_AGENT_SIGN_RESPONSE) {
1983e559 5066 logevent("Sending Pageant's response");
51470298 5067 ssh2_add_sigblob(ssh, s->pkblob, s->pklen,
5068 s->ret + 9,
5069 GET_32BIT(s->ret + 5));
5070 ssh2_pkt_send(ssh);
5071 s->authed = TRUE;
1983e559 5072 break;
5073 } else {
32874aea 5074 logevent
5075 ("Pageant failed to answer challenge");
51470298 5076 sfree(s->ret);
1983e559 5077 }
5078 }
5079 }
51470298 5080 if (s->authed)
1983e559 5081 continue;
5082 }
29b1d0b3 5083 sfree(s->response);
1983e559 5084 }
5085
51470298 5086 if (!s->method && s->can_pubkey && s->publickey_blob
5087 && !s->tried_pubkey_config) {
1408a877 5088 unsigned char *pub_blob;
5089 char *algorithm, *comment;
5090 int pub_blob_len;
65a22376 5091
51470298 5092 s->tried_pubkey_config = TRUE;
65a22376 5093
51470298 5094 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
5095 ssh->pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
00db133f 5096
65a22376 5097 /*
1408a877 5098 * Try the public key supplied in the configuration.
5099 *
5100 * First, offer the public blob to see if the server is
5101 * willing to accept it.
65a22376 5102 */
d8baa528 5103 pub_blob =
9a30e26b 5104 (unsigned char *)ssh2_userkey_loadpub(&ssh->cfg.keyfile,
d8baa528 5105 &algorithm,
222d54dc 5106 &pub_blob_len,
5107 NULL);
1408a877 5108 if (pub_blob) {
51470298 5109 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
5110 ssh2_pkt_addstring(ssh, s->username);
5111 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
5112 ssh2_pkt_addstring(ssh, "publickey"); /* method */
5113 ssh2_pkt_addbool(ssh, FALSE); /* no signature included */
5114 ssh2_pkt_addstring(ssh, algorithm);
5115 ssh2_pkt_addstring_start(ssh);
d8baa528 5116 ssh2_pkt_addstring_data(ssh, (char *)pub_blob,
5117 pub_blob_len);
51470298 5118 ssh2_pkt_send(ssh);
32874aea 5119 logevent("Offered public key"); /* FIXME */
1408a877 5120
5121 crWaitUntilV(ispkt);
51470298 5122 if (ssh->pktin.type != SSH2_MSG_USERAUTH_PK_OK) {
5123 s->gotit = TRUE;
5124 s->type = AUTH_TYPE_PUBLICKEY_OFFER_LOUD;
32874aea 5125 continue; /* key refused; give up on it */
1408a877 5126 }
65a22376 5127
1408a877 5128 logevent("Offer of public key accepted");
65a22376 5129 /*
1408a877 5130 * Actually attempt a serious authentication using
5131 * the key.
65a22376 5132 */
9a30e26b 5133 if (ssh2_userkey_encrypted(&ssh->cfg.keyfile, &comment)) {
51470298 5134 sprintf(s->pwprompt,
32874aea 5135 "Passphrase for key \"%.100s\": ",
5136 comment);
51470298 5137 s->need_pw = TRUE;
1408a877 5138 } else {
51470298 5139 s->need_pw = FALSE;
1408a877 5140 }
4e520718 5141 if (flags & FLAG_VERBOSE) {
5142 c_write_str(ssh, "Authenticating with public key \"");
5143 c_write_str(ssh, comment);
5144 c_write_str(ssh, "\"\r\n");
5145 }
51470298 5146 s->method = AUTH_PUBLICKEY_FILE;
65a22376 5147 }
1408a877 5148 }
5149
51470298 5150 if (!s->method && s->can_keyb_inter && !s->tried_keyb_inter) {
5151 s->method = AUTH_KEYBOARD_INTERACTIVE;
5152 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
5153 s->tried_keyb_inter = TRUE;
af659722 5154
51470298 5155 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
5156 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
00db133f 5157
51470298 5158 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
5159 ssh2_pkt_addstring(ssh, s->username);
5160 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
5161 ssh2_pkt_addstring(ssh, "keyboard-interactive"); /* method */
5162 ssh2_pkt_addstring(ssh, ""); /* lang */
5163 ssh2_pkt_addstring(ssh, "");
5164 ssh2_pkt_send(ssh);
af659722 5165
5166 crWaitUntilV(ispkt);
51470298 5167 if (ssh->pktin.type != SSH2_MSG_USERAUTH_INFO_REQUEST) {
5168 if (ssh->pktin.type == SSH2_MSG_USERAUTH_FAILURE)
5169 s->gotit = TRUE;
af659722 5170 logevent("Keyboard-interactive authentication refused");
51470298 5171 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET;
af659722 5172 continue;
5173 }
5174
51470298 5175 s->kbd_inter_running = TRUE;
5176 s->curr_prompt = 0;
af659722 5177 }
5178
51470298 5179 if (s->kbd_inter_running) {
5180 s->method = AUTH_KEYBOARD_INTERACTIVE;
5181 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
5182 s->tried_keyb_inter = TRUE;
af659722 5183
51470298 5184 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
5185 ssh->pkt_ctx |= SSH2_PKTCTX_KBDINTER;
00db133f 5186
51470298 5187 if (s->curr_prompt == 0) {
45068b27 5188 /*
5189 * We've got a fresh USERAUTH_INFO_REQUEST.
5190 * Display header data, and start going through
5191 * the prompts.
5192 */
5193 char *name, *inst, *lang;
5194 int name_len, inst_len, lang_len;
5195
0016d70b 5196 ssh_pkt_getstring(ssh, &name, &name_len);
5197 ssh_pkt_getstring(ssh, &inst, &inst_len);
5198 ssh_pkt_getstring(ssh, &lang, &lang_len);
45068b27 5199 if (name_len > 0) {
51470298 5200 c_write_untrusted(ssh, name, name_len);
5201 c_write_str(ssh, "\r\n");
45068b27 5202 }
5203 if (inst_len > 0) {
51470298 5204 c_write_untrusted(ssh, inst, inst_len);
5205 c_write_str(ssh, "\r\n");
45068b27 5206 }
0016d70b 5207 s->num_prompts = ssh_pkt_getuint32(ssh);
45068b27 5208 }
af659722 5209
45068b27 5210 /*
5211 * If there are prompts remaining in the packet,
5212 * display one and get a response.
5213 */
51470298 5214 if (s->curr_prompt < s->num_prompts) {
45068b27 5215 char *prompt;
5216 int prompt_len;
af659722 5217
0016d70b 5218 ssh_pkt_getstring(ssh, &prompt, &prompt_len);
45068b27 5219 if (prompt_len > 0) {
85fdbe25 5220 static const char trunc[] = "<prompt truncated>: ";
5221 static const int prlen = sizeof(s->pwprompt) -
5222 lenof(trunc);
5223 if (prompt_len > prlen) {
5224 memcpy(s->pwprompt, prompt, prlen);
5225 strcpy(s->pwprompt + prlen, trunc);
5226 } else {
5227 memcpy(s->pwprompt, prompt, prompt_len);
5228 s->pwprompt[prompt_len] = '\0';
5229 }
45068b27 5230 } else {
51470298 5231 strcpy(s->pwprompt,
45068b27 5232 "<server failed to send prompt>: ");
5233 }
51470298 5234 s->echo = ssh2_pkt_getbool(ssh);
5235 s->need_pw = TRUE;
45068b27 5236 } else
51470298 5237 s->need_pw = FALSE;
af659722 5238 }
5239
51470298 5240 if (!s->method && s->can_passwd) {
5241 s->method = AUTH_PASSWORD;
5242 ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
5243 ssh->pkt_ctx |= SSH2_PKTCTX_PASSWORD;
5244 sprintf(s->pwprompt, "%.90s@%.90s's password: ", s->username,
5245 ssh->savedhost);
5246 s->need_pw = TRUE;
1408a877 5247 }
5248
51470298 5249 if (s->need_pw) {
fa17a66e 5250 if (ssh_get_line) {
51470298 5251 if (!ssh_get_line(s->pwprompt, s->password,
5252 sizeof(s->password), TRUE)) {
1408a877 5253 /*
fa17a66e 5254 * get_line failed to get a password (for
5255 * example because one was supplied on the
5256 * command line which has already failed to
5257 * work). Terminate.
1408a877 5258 */
51470298 5259 ssh2_pkt_init(ssh, SSH2_MSG_DISCONNECT);
5260 ssh2_pkt_adduint32(ssh,SSH2_DISCONNECT_BY_APPLICATION);
5261 ssh2_pkt_addstring(ssh, "No more passwords available"
5262 " to try");
5263 ssh2_pkt_addstring(ssh, "en"); /* language tag */
5264 ssh2_pkt_send(ssh);
247308b5 5265 logevent("Unable to authenticate");
a8327734 5266 connection_fatal(ssh->frontend,
5267 "Unable to authenticate");
3bb2f322 5268 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 5269 crStopV;
1408a877 5270 }
5271 } else {
51470298 5272 int ret; /* need not be saved across crReturn */
5273 c_write_untrusted(ssh, s->pwprompt, strlen(s->pwprompt));
5274 ssh->send_ok = 1;
1408a877 5275
51470298 5276 setup_userpass_input(ssh, s->password,
5277 sizeof(s->password), s->echo);
0405e71f 5278 do {
1408a877 5279 crWaitUntilV(!ispkt);
51470298 5280 ret = process_userpass_input(ssh, in, inlen);
0405e71f 5281 } while (ret == 0);
5282 if (ret < 0)
5283 cleanup_exit(0);
51470298 5284 c_write_str(ssh, "\r\n");
65a22376 5285 }
65a22376 5286 }
65a22376 5287
51470298 5288 if (s->method == AUTH_PUBLICKEY_FILE) {
1408a877 5289 /*
5290 * We have our passphrase. Now try the actual authentication.
5291 */
5292 struct ssh2_userkey *key;
222d54dc 5293 const char *error = NULL;
65a22376 5294
222d54dc 5295 key = ssh2_load_userkey(&ssh->cfg.keyfile, s->password,
5296 &error);
1408a877 5297 if (key == SSH2_WRONG_PASSPHRASE || key == NULL) {
5298 if (key == SSH2_WRONG_PASSPHRASE) {
51470298 5299 c_write_str(ssh, "Wrong passphrase\r\n");
5300 s->tried_pubkey_config = FALSE;
1408a877 5301 } else {
222d54dc 5302 c_write_str(ssh, "Unable to load private key (");
5303 c_write_str(ssh, error);
5304 c_write_str(ssh, ")\r\n");
51470298 5305 s->tried_pubkey_config = TRUE;
1408a877 5306 }
5307 /* Send a spurious AUTH_NONE to return to the top. */
51470298 5308 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
5309 ssh2_pkt_addstring(ssh, s->username);
5310 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
5311 ssh2_pkt_addstring(ssh, "none"); /* method */
5312 ssh2_pkt_send(ssh);
5313 s->type = AUTH_TYPE_NONE;
1408a877 5314 } else {
1dd353b5 5315 unsigned char *pkblob, *sigblob, *sigdata;
5316 int pkblob_len, sigblob_len, sigdata_len;
dda87a28 5317 int p;
65a22376 5318
1408a877 5319 /*
5320 * We have loaded the private key and the server
5321 * has announced that it's willing to accept it.
5322 * Hallelujah. Generate a signature and send it.
5323 */
51470298 5324 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
5325 ssh2_pkt_addstring(ssh, s->username);
5326 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
5327 ssh2_pkt_addstring(ssh, "publickey"); /* method */
5328 ssh2_pkt_addbool(ssh, TRUE);
5329 ssh2_pkt_addstring(ssh, key->alg->name);
1dd353b5 5330 pkblob = key->alg->public_blob(key->data, &pkblob_len);
51470298 5331 ssh2_pkt_addstring_start(ssh);
d8baa528 5332 ssh2_pkt_addstring_data(ssh, (char *)pkblob, pkblob_len);
1408a877 5333
5334 /*
5335 * The data to be signed is:
5336 *
5337 * string session-id
5338 *
5339 * followed by everything so far placed in the
5340 * outgoing packet.
5341 */
51470298 5342 sigdata_len = ssh->pktout.length - 5 + 4 + 20;
dda87a28 5343 if (ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)
5344 sigdata_len -= 4;
92d60585 5345 sigdata = snewn(sigdata_len, unsigned char);
dda87a28 5346 p = 0;
5347 if (!(ssh->remote_bugs & BUG_SSH2_PK_SESSIONID)) {
5348 PUT_32BIT(sigdata+p, 20);
5349 p += 4;
5350 }
5351 memcpy(sigdata+p, ssh->v2_session_id, 20); p += 20;
5352 memcpy(sigdata+p, ssh->pktout.data + 5,
51470298 5353 ssh->pktout.length - 5);
dda87a28 5354 p += ssh->pktout.length - 5;
5355 assert(p == sigdata_len);
d8baa528 5356 sigblob = key->alg->sign(key->data, (char *)sigdata,
1dd353b5 5357 sigdata_len, &sigblob_len);
51470298 5358 ssh2_add_sigblob(ssh, pkblob, pkblob_len,
1dd353b5 5359 sigblob, sigblob_len);
5360 sfree(pkblob);
5361 sfree(sigblob);
1408a877 5362 sfree(sigdata);
5363
51470298 5364 ssh2_pkt_send(ssh);
5365 s->type = AUTH_TYPE_PUBLICKEY;
75374b2f 5366 key->alg->freekey(key->data);
1408a877 5367 }
51470298 5368 } else if (s->method == AUTH_PASSWORD) {
65a22376 5369 /*
1408a877 5370 * We send the password packet lumped tightly together with
5371 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
5372 * string long enough to make the total length of the two
5373 * packets constant. This should ensure that a passive
5374 * listener doing traffic analyis can't work out the length
5375 * of the password.
5376 *
5377 * For this to work, we need an assumption about the
5378 * maximum length of the password packet. I think 256 is
5379 * pretty conservative. Anyone using a password longer than
5380 * that probably doesn't have much to worry about from
5381 * people who find out how long their password is!
65a22376 5382 */
51470298 5383 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
5384 ssh2_pkt_addstring(ssh, s->username);
5385 ssh2_pkt_addstring(ssh, "ssh-connection"); /* service requested */
5386 ssh2_pkt_addstring(ssh, "password");
5387 ssh2_pkt_addbool(ssh, FALSE);
5388 ssh2_pkt_addstring(ssh, s->password);
1409c1b3 5389 memset(s->password, 0, sizeof(s->password));
51470298 5390 ssh2_pkt_defer(ssh);
65a22376 5391 /*
1408a877 5392 * We'll include a string that's an exact multiple of the
5393 * cipher block size. If the cipher is NULL for some
5394 * reason, we don't do this trick at all because we gain
5395 * nothing by it.
65a22376 5396 */
51470298 5397 if (ssh->cscipher) {
32874aea 5398 int stringlen, i;
5399
51470298 5400 stringlen = (256 - ssh->deferred_len);
5401 stringlen += ssh->cscipher->blksize - 1;
5402 stringlen -= (stringlen % ssh->cscipher->blksize);
5403 if (ssh->cscomp) {
32874aea 5404 /*
5405 * Temporarily disable actual compression,
5406 * so we can guarantee to get this string
5407 * exactly the length we want it. The
5408 * compression-disabling routine should
5409 * return an integer indicating how many
5410 * bytes we should adjust our string length
5411 * by.
5412 */
5366aed8 5413 stringlen -=
5414 ssh->cscomp->disable_compression(ssh->cs_comp_ctx);
32874aea 5415 }
51470298 5416 ssh2_pkt_init(ssh, SSH2_MSG_IGNORE);
5417 ssh2_pkt_addstring_start(ssh);
6e9e9520 5418 for (i = 0; i < stringlen; i++) {
32874aea 5419 char c = (char) random_byte();
51470298 5420 ssh2_pkt_addstring_data(ssh, &c, 1);
65a22376 5421 }
51470298 5422 ssh2_pkt_defer(ssh);
65a22376 5423 }
51470298 5424 ssh_pkt_defersend(ssh);
0d43337a 5425 logevent("Sent password");
51470298 5426 s->type = AUTH_TYPE_PASSWORD;
5427 } else if (s->method == AUTH_KEYBOARD_INTERACTIVE) {
5428 if (s->curr_prompt == 0) {
5429 ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_INFO_RESPONSE);
5430 ssh2_pkt_adduint32(ssh, s->num_prompts);
45068b27 5431 }
51470298 5432 if (s->need_pw) { /* only add pw if we just got one! */
5433 ssh2_pkt_addstring(ssh, s->password);
5434 memset(s->password, 0, sizeof(s->password));
5435 s->curr_prompt++;
45068b27 5436 }
51470298 5437 if (s->curr_prompt >= s->num_prompts) {
5438 ssh2_pkt_send(ssh);
45068b27 5439 } else {
5440 /*
5441 * If there are prompts remaining, we set
5442 * `gotit' so that we won't attempt to get
5443 * another packet. Then we go back round the
5444 * loop and will end up retrieving another
5445 * prompt out of the existing packet. Funky or
5446 * what?
5447 */
51470298 5448 s->gotit = TRUE;
45068b27 5449 }
51470298 5450 s->type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
1408a877 5451 } else {
51470298 5452 c_write_str(ssh, "No supported authentication methods"
5453 " left to try!\r\n");
5454 logevent("No supported authentications offered."
5455 " Disconnecting");
5456 ssh2_pkt_init(ssh, SSH2_MSG_DISCONNECT);
5457 ssh2_pkt_adduint32(ssh, SSH2_DISCONNECT_BY_APPLICATION);
5458 ssh2_pkt_addstring(ssh, "No supported authentication"
5459 " methods available");
5460 ssh2_pkt_addstring(ssh, "en"); /* language tag */
5461 ssh2_pkt_send(ssh);
3bb2f322 5462 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 5463 crStopV;
65a22376 5464 }
65a22376 5465 }
51470298 5466 } while (!s->we_are_in);
7cca0d81 5467
5468 /*
5469 * Now we're authenticated for the connection protocol. The
5470 * connection protocol will automatically have started at this
5471 * point; there's no need to send SERVICE_REQUEST.
5472 */
5473
5474 /*
5475 * So now create a channel with a session in it.
5476 */
51470298 5477 ssh->channels = newtree234(ssh_channelcmp);
3d88e64d 5478 ssh->mainchan = snew(struct ssh_channel);
51470298 5479 ssh->mainchan->ssh = ssh;
5480 ssh->mainchan->localid = alloc_channel_id(ssh);
5481 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_OPEN);
5482 ssh2_pkt_addstring(ssh, "session");
5483 ssh2_pkt_adduint32(ssh, ssh->mainchan->localid);
5484 ssh->mainchan->v.v2.locwindow = OUR_V2_WINSIZE;
5485 ssh2_pkt_adduint32(ssh, ssh->mainchan->v.v2.locwindow);/* our window size */
5486 ssh2_pkt_adduint32(ssh, 0x4000UL); /* our max pkt size */
5487 ssh2_pkt_send(ssh);
7cca0d81 5488 crWaitUntilV(ispkt);
51470298 5489 if (ssh->pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
6b5cf8b4 5490 bombout(("Server refused to open a session"));
7ffdbc1a 5491 crStopV;
32874aea 5492 /* FIXME: error data comes back in FAILURE packet */
7cca0d81 5493 }
0016d70b 5494 if (ssh_pkt_getuint32(ssh) != ssh->mainchan->localid) {
6b5cf8b4 5495 bombout(("Server's channel confirmation cited wrong channel"));
7ffdbc1a 5496 crStopV;
7cca0d81 5497 }
0016d70b 5498 ssh->mainchan->remoteid = ssh_pkt_getuint32(ssh);
51470298 5499 ssh->mainchan->type = CHAN_MAINSESSION;
5500 ssh->mainchan->closes = 0;
0016d70b 5501 ssh->mainchan->v.v2.remwindow = ssh_pkt_getuint32(ssh);
5502 ssh->mainchan->v.v2.remmaxpkt = ssh_pkt_getuint32(ssh);
51470298 5503 bufchain_init(&ssh->mainchan->v.v2.outbuffer);
5504 add234(ssh->channels, ssh->mainchan);
7cca0d81 5505 logevent("Opened channel for session");
5506
5507 /*
783415f8 5508 * Potentially enable X11 forwarding.
5509 */
86916870 5510 if (ssh->cfg.x11_forward) {
32874aea 5511 char proto[20], data[64];
5512 logevent("Requesting X11 forwarding");
302121de 5513 ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
86916870 5514 data, sizeof(data), ssh->cfg.x11_auth);
5515 x11_get_real_auth(ssh->x11auth, ssh->cfg.x11_display);
51470298 5516 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
5517 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
5518 ssh2_pkt_addstring(ssh, "x11-req");
5519 ssh2_pkt_addbool(ssh, 1); /* want reply */
5520 ssh2_pkt_addbool(ssh, 0); /* many connections */
5521 ssh2_pkt_addstring(ssh, proto);
5522 ssh2_pkt_addstring(ssh, data);
86916870 5523 ssh2_pkt_adduint32(ssh, x11_get_screen_number(ssh->cfg.x11_display));
51470298 5524 ssh2_pkt_send(ssh);
32874aea 5525
5526 do {
5527 crWaitUntilV(ispkt);
51470298 5528 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
0016d70b 5529 unsigned i = ssh_pkt_getuint32(ssh);
32874aea 5530 struct ssh_channel *c;
51470298 5531 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5532 if (!c)
5533 continue; /* nonexistent channel */
0016d70b 5534 c->v.v2.remwindow += ssh_pkt_getuint32(ssh);
32874aea 5535 }
51470298 5536 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
32874aea 5537
51470298 5538 if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
5539 if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 5540 bombout(("Unexpected response to X11 forwarding request:"
51470298 5541 " packet type %d", ssh->pktin.type));
7ffdbc1a 5542 crStopV;
32874aea 5543 }
5544 logevent("X11 forwarding refused");
5545 } else {
5546 logevent("X11 forwarding enabled");
51470298 5547 ssh->X11_fwd_enabled = TRUE;
32874aea 5548 }
783415f8 5549 }
5550
5551 /*
bc240b21 5552 * Enable port forwardings.
5553 */
5554 {
bc240b21 5555 char type;
5556 int n;
a4fc0d74 5557 int sport,dport,sserv,dserv;
6ee9b735 5558 char sports[256], dports[256], saddr[256], host[256];
bc240b21 5559
51470298 5560 ssh->rportfwds = newtree234(ssh_rportcmp_ssh2);
bc240b21 5561 /* Add port forwardings. */
86916870 5562 ssh->portfwd_strptr = ssh->cfg.portfwd;
51470298 5563 while (*ssh->portfwd_strptr) {
5564 type = *ssh->portfwd_strptr++;
6ee9b735 5565 saddr[0] = '\0';
bc240b21 5566 n = 0;
6ee9b735 5567 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != '\t') {
5568 if (*ssh->portfwd_strptr == ':') {
5569 /*
5570 * We've seen a colon in the middle of the
5571 * source port number. This means that
5572 * everything we've seen until now is the
5573 * source _address_, so we'll move it into
5574 * saddr and start sports from the beginning
5575 * again.
5576 */
5577 ssh->portfwd_strptr++;
5578 sports[n] = '\0';
5579 strcpy(saddr, sports);
5580 n = 0;
5581 }
5582 if (n < 255) sports[n++] = *ssh->portfwd_strptr++;
5583 }
bc240b21 5584 sports[n] = 0;
820ebe3b 5585 if (type != 'D') {
5586 if (*ssh->portfwd_strptr == '\t')
5587 ssh->portfwd_strptr++;
5588 n = 0;
5589 while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != ':') {
5590 if (n < 255) host[n++] = *ssh->portfwd_strptr++;
5591 }
5592 host[n] = 0;
5593 if (*ssh->portfwd_strptr == ':')
5594 ssh->portfwd_strptr++;
5595 n = 0;
5596 while (*ssh->portfwd_strptr) {
5597 if (n < 255) dports[n++] = *ssh->portfwd_strptr++;
5598 }
5599 dports[n] = 0;
51470298 5600 ssh->portfwd_strptr++;
820ebe3b 5601 dport = atoi(dports);
5602 dserv = 0;
5603 if (dport == 0) {
5604 dserv = 1;
5605 dport = net_service_lookup(dports);
5606 if (!dport) {
5607 logeventf(ssh, "Service lookup failed for destination"
5608 " port \"%s\"", dports);
5609 }
a4fc0d74 5610 }
820ebe3b 5611 } else {
5612 while (*ssh->portfwd_strptr) ssh->portfwd_strptr++;
7ffdbc1a 5613 dport = dserv = -1;
7d5b0f4d 5614 ssh->portfwd_strptr++; /* eat the NUL and move to next one */
a4fc0d74 5615 }
bc240b21 5616 sport = atoi(sports);
a4fc0d74 5617 sserv = 0;
5618 if (sport == 0) {
5619 sserv = 1;
68a49acb 5620 sport = net_service_lookup(sports);
5621 if (!sport) {
57356d63 5622 logeventf(ssh, "Service lookup failed for source"
5623 " port \"%s\"", sports);
a4fc0d74 5624 }
5625 }
bc240b21 5626 if (sport && dport) {
94ab1ddf 5627 /* Set up a description of the source port. */
5628 char *sportdesc = dupprintf("%.*s%.*s%.*s%.*s%d%.*s",
5629 (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
5630 (int)(*saddr?1:0), ":",
5631 (int)(sserv ? strlen(sports) : 0), sports,
5632 sserv, "(", sport, sserv, ")");
bc240b21 5633 if (type == 'L') {
94ab1ddf 5634 /* Verbose description of the destination port */
5635 char *dportdesc = dupprintf("%s:%.*s%.*s%d%.*s",
5636 host,
5637 (int)(dserv ? strlen(dports) : 0), dports,
5638 dserv, "(", dport, dserv, ")");
5639 const char *err = pfd_addforward(host, dport,
5640 *saddr ? saddr : NULL,
5641 sport, ssh, &ssh->cfg);
5642 if (err) {
5643 logeventf(ssh, "Local port %s forward to %s"
5644 " failed: %s", sportdesc, dportdesc, err);
5645 } else {
5646 logeventf(ssh, "Local port %s forwarding to %s",
5647 sportdesc, dportdesc);
5648 }
5649 sfree(dportdesc);
820ebe3b 5650 } else if (type == 'D') {
94ab1ddf 5651 const char *err = pfd_addforward(NULL, -1,
5652 *saddr ? saddr : NULL,
5653 sport, ssh, &ssh->cfg);
5654 if (err) {
5655 logeventf(ssh, "Local port %s SOCKS dynamic forward"
5656 " setup failed: %s", sportdesc, err);
5657 } else {
5658 logeventf(ssh, "Local port %s doing SOCKS"
5659 " dynamic forwarding", sportdesc);
5660 }
bc240b21 5661 } else {
5662 struct ssh_rportfwd *pf;
3d88e64d 5663 pf = snew(struct ssh_rportfwd);
bc240b21 5664 strcpy(pf->dhost, host);
5665 pf->dport = dport;
5666 pf->sport = sport;
51470298 5667 if (add234(ssh->rportfwds, pf) != pf) {
57356d63 5668 logeventf(ssh, "Duplicate remote port forwarding"
5669 " to %s:%d", host, dport);
bc240b21 5670 sfree(pf);
5671 } else {
94ab1ddf 5672 logeventf(ssh, "Requesting remote port %s"
57356d63 5673 " forward to %s:%.*s%.*s%d%.*s",
94ab1ddf 5674 sportdesc,
57356d63 5675 host,
5676 (int)(dserv ? strlen(dports) : 0), dports,
5677 dserv, "(", dport, dserv, ")");
51470298 5678 ssh2_pkt_init(ssh, SSH2_MSG_GLOBAL_REQUEST);
5679 ssh2_pkt_addstring(ssh, "tcpip-forward");
5680 ssh2_pkt_addbool(ssh, 1);/* want reply */
6ee9b735 5681 if (*saddr)
5682 ssh2_pkt_addstring(ssh, saddr);
86916870 5683 if (ssh->cfg.rport_acceptall)
51470298 5684 ssh2_pkt_addstring(ssh, "0.0.0.0");
beefa433 5685 else
51470298 5686 ssh2_pkt_addstring(ssh, "127.0.0.1");
5687 ssh2_pkt_adduint32(ssh, sport);
5688 ssh2_pkt_send(ssh);
bc240b21 5689
5690 do {
5691 crWaitUntilV(ispkt);
51470298 5692 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
0016d70b 5693 unsigned i = ssh_pkt_getuint32(ssh);
bc240b21 5694 struct ssh_channel *c;
51470298 5695 c = find234(ssh->channels, &i, ssh_channelfind);
bc240b21 5696 if (!c)
5697 continue;/* nonexistent channel */
0016d70b 5698 c->v.v2.remwindow += ssh_pkt_getuint32(ssh);
bc240b21 5699 }
51470298 5700 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
bc240b21 5701
51470298 5702 if (ssh->pktin.type != SSH2_MSG_REQUEST_SUCCESS) {
5703 if (ssh->pktin.type != SSH2_MSG_REQUEST_FAILURE) {
6b5cf8b4 5704 bombout(("Unexpected response to port "
c9886e66 5705 "forwarding request: packet type %d",
51470298 5706 ssh->pktin.type));
7ffdbc1a 5707 crStopV;
bc240b21 5708 }
5709 logevent("Server refused this port forwarding");
5710 } else {
5711 logevent("Remote port forwarding enabled");
5712 }
5713 }
5714 }
94ab1ddf 5715 sfree(sportdesc);
bc240b21 5716 }
5717 }
5718 }
5719
5720 /*
36c2a3e9 5721 * Potentially enable agent forwarding.
5722 */
86916870 5723 if (ssh->cfg.agentfwd && agent_exists()) {
32874aea 5724 logevent("Requesting OpenSSH-style agent forwarding");
51470298 5725 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
5726 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
5727 ssh2_pkt_addstring(ssh, "auth-agent-req@openssh.com");
5728 ssh2_pkt_addbool(ssh, 1); /* want reply */
5729 ssh2_pkt_send(ssh);
32874aea 5730
5731 do {
5732 crWaitUntilV(ispkt);
51470298 5733 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
0016d70b 5734 unsigned i = ssh_pkt_getuint32(ssh);
32874aea 5735 struct ssh_channel *c;
51470298 5736 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5737 if (!c)
5738 continue; /* nonexistent channel */
0016d70b 5739 c->v.v2.remwindow += ssh_pkt_getuint32(ssh);
32874aea 5740 }
51470298 5741 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
32874aea 5742
51470298 5743 if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
5744 if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 5745 bombout(("Unexpected response to agent forwarding request:"
51470298 5746 " packet type %d", ssh->pktin.type));
7ffdbc1a 5747 crStopV;
32874aea 5748 }
5749 logevent("Agent forwarding refused");
5750 } else {
5751 logevent("Agent forwarding enabled");
51470298 5752 ssh->agentfwd_enabled = TRUE;
32874aea 5753 }
36c2a3e9 5754 }
5755
5756 /*
7cca0d81 5757 * Now allocate a pty for the session.
5758 */
86916870 5759 if (!ssh->cfg.nopty) {
a5dd8467 5760 /* Unpick the terminal-speed string. */
5761 /* XXX perhaps we should allow no speeds to be sent. */
db219738 5762 ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
5763 sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
a5dd8467 5764 /* Build the pty request. */
51470298 5765 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
5766 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid); /* recipient channel */
5767 ssh2_pkt_addstring(ssh, "pty-req");
5768 ssh2_pkt_addbool(ssh, 1); /* want reply */
86916870 5769 ssh2_pkt_addstring(ssh, ssh->cfg.termtype);
51470298 5770 ssh2_pkt_adduint32(ssh, ssh->term_width);
5771 ssh2_pkt_adduint32(ssh, ssh->term_height);
5772 ssh2_pkt_adduint32(ssh, 0); /* pixel width */
5773 ssh2_pkt_adduint32(ssh, 0); /* pixel height */
5774 ssh2_pkt_addstring_start(ssh);
a5dd8467 5775 ssh2_pkt_addbyte(ssh, 128); /* TTY_OP_ISPEED */
db219738 5776 ssh2_pkt_adduint32(ssh, ssh->ispeed);
a5dd8467 5777 ssh2_pkt_addbyte(ssh, 129); /* TTY_OP_OSPEED */
db219738 5778 ssh2_pkt_adduint32(ssh, ssh->ospeed);
a5dd8467 5779 ssh2_pkt_addstring_data(ssh, "\0", 1); /* TTY_OP_END */
51470298 5780 ssh2_pkt_send(ssh);
5781 ssh->state = SSH_STATE_INTERMED;
32874aea 5782
5783 do {
5784 crWaitUntilV(ispkt);
51470298 5785 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
0016d70b 5786 unsigned i = ssh_pkt_getuint32(ssh);
32874aea 5787 struct ssh_channel *c;
51470298 5788 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5789 if (!c)
5790 continue; /* nonexistent channel */
0016d70b 5791 c->v.v2.remwindow += ssh_pkt_getuint32(ssh);
32874aea 5792 }
51470298 5793 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
32874aea 5794
51470298 5795 if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
5796 if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 5797 bombout(("Unexpected response to pty request:"
51470298 5798 " packet type %d", ssh->pktin.type));
7ffdbc1a 5799 crStopV;
32874aea 5800 }
51470298 5801 c_write_str(ssh, "Server refused to allocate pty\r\n");
5802 ssh->editing = ssh->echoing = 1;
32874aea 5803 } else {
a5dd8467 5804 logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
db219738 5805 ssh->ospeed, ssh->ispeed);
32874aea 5806 }
0965bee0 5807 } else {
51470298 5808 ssh->editing = ssh->echoing = 1;
7cca0d81 5809 }
5810
5811 /*
fd5e5847 5812 * Start a shell or a remote command. We may have to attempt
5813 * this twice if the config data has provided a second choice
5814 * of command.
7cca0d81 5815 */
fd5e5847 5816 while (1) {
5817 int subsys;
5818 char *cmd;
5819
51470298 5820 if (ssh->fallback_cmd) {
86916870 5821 subsys = ssh->cfg.ssh_subsys2;
5822 cmd = ssh->cfg.remote_cmd_ptr2;
fd5e5847 5823 } else {
86916870 5824 subsys = ssh->cfg.ssh_subsys;
5825 cmd = ssh->cfg.remote_cmd_ptr;
fd5e5847 5826 }
5827
51470298 5828 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
5829 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid); /* recipient channel */
fd5e5847 5830 if (subsys) {
51470298 5831 ssh2_pkt_addstring(ssh, "subsystem");
5832 ssh2_pkt_addbool(ssh, 1); /* want reply */
5833 ssh2_pkt_addstring(ssh, cmd);
fd5e5847 5834 } else if (*cmd) {
51470298 5835 ssh2_pkt_addstring(ssh, "exec");
5836 ssh2_pkt_addbool(ssh, 1); /* want reply */
5837 ssh2_pkt_addstring(ssh, cmd);
fd5e5847 5838 } else {
51470298 5839 ssh2_pkt_addstring(ssh, "shell");
5840 ssh2_pkt_addbool(ssh, 1); /* want reply */
32874aea 5841 }
51470298 5842 ssh2_pkt_send(ssh);
fd5e5847 5843 do {
5844 crWaitUntilV(ispkt);
51470298 5845 if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
0016d70b 5846 unsigned i = ssh_pkt_getuint32(ssh);
fd5e5847 5847 struct ssh_channel *c;
51470298 5848 c = find234(ssh->channels, &i, ssh_channelfind);
fd5e5847 5849 if (!c)
5850 continue; /* nonexistent channel */
0016d70b 5851 c->v.v2.remwindow += ssh_pkt_getuint32(ssh);
fd5e5847 5852 }
51470298 5853 } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
5854 if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
5855 if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
6b5cf8b4 5856 bombout(("Unexpected response to shell/command request:"
51470298 5857 " packet type %d", ssh->pktin.type));
7ffdbc1a 5858 crStopV;
fd5e5847 5859 }
5860 /*
5861 * We failed to start the command. If this is the
5862 * fallback command, we really are finished; if it's
5863 * not, and if the fallback command exists, try falling
5864 * back to it before complaining.
5865 */
86916870 5866 if (!ssh->fallback_cmd && ssh->cfg.remote_cmd_ptr2 != NULL) {
fd5e5847 5867 logevent("Primary command failed; attempting fallback");
51470298 5868 ssh->fallback_cmd = TRUE;
fd5e5847 5869 continue;
5870 }
6b5cf8b4 5871 bombout(("Server refused to start a shell/command"));
7ffdbc1a 5872 crStopV;
fd5e5847 5873 } else {
5874 logevent("Started a shell/command");
32874aea 5875 }
fd5e5847 5876 break;
7cca0d81 5877 }
5878
51470298 5879 ssh->state = SSH_STATE_SESSION;
5880 if (ssh->size_needed)
5881 ssh_size(ssh, ssh->term_width, ssh->term_height);
5882 if (ssh->eof_needed)
5883 ssh_special(ssh, TS_EOF);
6e48c3fe 5884
7cca0d81 5885 /*
5886 * Transfer data!
5887 */
b9d7bcad 5888 if (ssh->ldisc)
5889 ldisc_send(ssh->ldisc, NULL, 0, 0);/* cause ldisc to notice changes */
51470298 5890 ssh->send_ok = 1;
7cca0d81 5891 while (1) {
e5574168 5892 crReturnV;
51470298 5893 s->try_send = FALSE;
7cca0d81 5894 if (ispkt) {
51470298 5895 if (ssh->pktin.type == SSH2_MSG_CHANNEL_DATA ||
5896 ssh->pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
32874aea 5897 char *data;
5898 int length;
0016d70b 5899 unsigned i = ssh_pkt_getuint32(ssh);
32874aea 5900 struct ssh_channel *c;
51470298 5901 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5902 if (!c)
5903 continue; /* nonexistent channel */
51470298 5904 if (ssh->pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
0016d70b 5905 ssh_pkt_getuint32(ssh) != SSH2_EXTENDED_DATA_STDERR)
32874aea 5906 continue; /* extended but not stderr */
0016d70b 5907 ssh_pkt_getstring(ssh, &data, &length);
32874aea 5908 if (data) {
7ffdbc1a 5909 int bufsize = 0;
5471d09a 5910 c->v.v2.locwindow -= length;
32874aea 5911 switch (c->type) {
5912 case CHAN_MAINSESSION:
5471d09a 5913 bufsize =
51470298 5914 from_backend(ssh->frontend, ssh->pktin.type ==
5471d09a 5915 SSH2_MSG_CHANNEL_EXTENDED_DATA,
5916 data, length);
32874aea 5917 break;
5918 case CHAN_X11:
5471d09a 5919 bufsize = x11_send(c->u.x11.s, data, length);
32874aea 5920 break;
d74d141c 5921 case CHAN_SOCKDATA:
5471d09a 5922 bufsize = pfd_send(c->u.pfd.s, data, length);
bc240b21 5923 break;
36c2a3e9 5924 case CHAN_AGENT:
32874aea 5925 while (length > 0) {
5926 if (c->u.a.lensofar < 4) {
5927 int l = min(4 - c->u.a.lensofar, length);
5928 memcpy(c->u.a.msglen + c->u.a.lensofar,
5929 data, l);
5930 data += l;
5931 length -= l;
5932 c->u.a.lensofar += l;
5933 }
5934 if (c->u.a.lensofar == 4) {
5935 c->u.a.totallen =
5936 4 + GET_32BIT(c->u.a.msglen);
3d88e64d 5937 c->u.a.message = snewn(c->u.a.totallen,
5938 unsigned char);
32874aea 5939 memcpy(c->u.a.message, c->u.a.msglen, 4);
5940 }
5941 if (c->u.a.lensofar >= 4 && length > 0) {
5942 int l =
5943 min(c->u.a.totallen - c->u.a.lensofar,
5944 length);
5945 memcpy(c->u.a.message + c->u.a.lensofar,
5946 data, l);
5947 data += l;
5948 length -= l;
5949 c->u.a.lensofar += l;
5950 }
5951 if (c->u.a.lensofar == c->u.a.totallen) {
839f10db 5952 void *reply;
32874aea 5953 int replylen;
839f10db 5954 if (agent_query(c->u.a.message,
5955 c->u.a.totallen,
5956 &reply, &replylen,
5957 ssh_agentf_callback, c))
5958 ssh_agentf_callback(c, reply, replylen);
32874aea 5959 sfree(c->u.a.message);
5960 c->u.a.lensofar = 0;
5961 }
5962 }
5471d09a 5963 bufsize = 0;
32874aea 5964 break;
5965 }
5966 /*
5471d09a 5967 * If we are not buffering too much data,
5968 * enlarge the window again at the remote side.
32874aea 5969 */
5471d09a 5970 if (bufsize < OUR_V2_WINSIZE)
5971 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
32874aea 5972 }
51470298 5973 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_EOF) {
0016d70b 5974 unsigned i = ssh_pkt_getuint32(ssh);
32874aea 5975 struct ssh_channel *c;
5976
51470298 5977 c = find234(ssh->channels, &i, ssh_channelfind);
32874aea 5978 if (!c)
5979 continue; /* nonexistent channel */
5980
5981 if (c->type == CHAN_X11) {
5982 /*
5983 * Remote EOF on an X11 channel means we should
5984 * wrap up and close the channel ourselves.
5985 */
5986 x11_close(c->u.x11.s);
5987 sshfwd_close(c);
5988 } else if (c->type == CHAN_AGENT) {
36c2a3e9 5989 sshfwd_close(c);
d74d141c 5990 } else if (c->type == CHAN_SOCKDATA) {
bc240b21 5991 pfd_close(c->u.pfd.s);
5992 sshfwd_close(c);
36c2a3e9 5993 }
51470298 5994 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_CLOSE) {
0016d70b 5995 unsigned i = ssh_pkt_getuint32(ssh);
32874aea 5996 struct ssh_channel *c;
5997
51470298 5998 c = find234(ssh->channels, &i, ssh_channelfind);
d0d844c1 5999 if (!c || ((int)c->remoteid) == -1) {
6b5cf8b4 6000 bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
d0d844c1 6001 c ? "half-open" : "nonexistent", i));
7ffdbc1a 6002 crStopV;
d0d844c1 6003 }
32874aea 6004 /* Do pre-close processing on the channel. */
6005 switch (c->type) {
6006 case CHAN_MAINSESSION:
6007 break; /* nothing to see here, move along */
6008 case CHAN_X11:
92f157bd 6009 if (c->u.x11.s != NULL)
6010 x11_close(c->u.x11.s);
6011 sshfwd_close(c);
32874aea 6012 break;
6013 case CHAN_AGENT:
92f157bd 6014 sshfwd_close(c);
32874aea 6015 break;
d74d141c 6016 case CHAN_SOCKDATA:
92f157bd 6017 if (c->u.pfd.s != NULL)
6018 pfd_close(c->u.pfd.s);
6019 sshfwd_close(c);
bc240b21 6020 break;
32874aea 6021 }
92f157bd 6022 if (c->closes == 0) {
51470298 6023 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_CLOSE);
6024 ssh2_pkt_adduint32(ssh, c->remoteid);
6025 ssh2_pkt_send(ssh);
92f157bd 6026 }
51470298 6027 del234(ssh->channels, c);
5471d09a 6028 bufchain_clear(&c->v.v2.outbuffer);
32874aea 6029 sfree(c);
6030
6031 /*
6032 * See if that was the last channel left open.
6033 */
51470298 6034 if (count234(ssh->channels) == 0) {
3bb2f322 6035 logevent("All channels closed. Disconnecting");
ca2914d1 6036#if 0
6037 /*
6038 * We used to send SSH_MSG_DISCONNECT here,
6039 * because I'd believed that _every_ conforming
6040 * SSH2 connection had to end with a disconnect
6041 * being sent by at least one side; apparently
6042 * I was wrong and it's perfectly OK to
6043 * unceremoniously slam the connection shut
6044 * when you're done, and indeed OpenSSH feels
6045 * this is more polite than sending a
6046 * DISCONNECT. So now we don't.
6047 */
51470298 6048 ssh2_pkt_init(ssh, SSH2_MSG_DISCONNECT);
6049 ssh2_pkt_adduint32(ssh, SSH2_DISCONNECT_BY_APPLICATION);
6050 ssh2_pkt_addstring(ssh, "All open channels closed");
6051 ssh2_pkt_addstring(ssh, "en"); /* language tag */
6052 ssh2_pkt_send(ssh);
ca2914d1 6053#endif
3bb2f322 6054 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 6055 crStopV;
32874aea 6056 }
6057 continue; /* remote sends close; ignore (FIXME) */
51470298 6058 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
0016d70b 6059 unsigned i = ssh_pkt_getuint32(ssh);
32874aea 6060 struct ssh_channel *c;
51470298 6061 c = find234(ssh->channels, &i, ssh_channelfind);
a6253970 6062 if (!c || c->closes)
6063 continue; /* nonexistent or closing channel */
0016d70b 6064 c->v.v2.remwindow += ssh_pkt_getuint32(ssh);
51470298 6065 s->try_send = TRUE;
6066 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
0016d70b 6067 unsigned i = ssh_pkt_getuint32(ssh);
bc240b21 6068 struct ssh_channel *c;
51470298 6069 c = find234(ssh->channels, &i, ssh_channelfind);
bc240b21 6070 if (!c)
6071 continue; /* nonexistent channel */
6072 if (c->type != CHAN_SOCKDATA_DORMANT)
6073 continue; /* dunno why they're confirming this */
0016d70b 6074 c->remoteid = ssh_pkt_getuint32(ssh);
bc240b21 6075 c->type = CHAN_SOCKDATA;
0016d70b 6076 c->v.v2.remwindow = ssh_pkt_getuint32(ssh);
6077 c->v.v2.remmaxpkt = ssh_pkt_getuint32(ssh);
4ed34d25 6078 if (c->u.pfd.s)
6079 pfd_confirm(c->u.pfd.s);
6080 if (c->closes) {
6081 /*
6082 * We have a pending close on this channel,
6083 * which we decided on before the server acked
6084 * the channel open. So now we know the
6085 * remoteid, we can close it again.
6086 */
51470298 6087 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_CLOSE);
6088 ssh2_pkt_adduint32(ssh, c->remoteid);
6089 ssh2_pkt_send(ssh);
4ed34d25 6090 }
51470298 6091 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_OPEN_FAILURE) {
e595953d 6092 static const char *const reasons[] = {
6093 "<unknown reason code>",
6094 "Administratively prohibited",
6095 "Connect failed",
6096 "Unknown channel type",
6097 "Resource shortage",
6098 };
0016d70b 6099 unsigned i = ssh_pkt_getuint32(ssh);
e595953d 6100 unsigned reason_code;
6101 char *reason_string;
6102 int reason_length;
6103 char *message;
724cface 6104 struct ssh_channel *c;
51470298 6105 c = find234(ssh->channels, &i, ssh_channelfind);
724cface 6106 if (!c)
6107 continue; /* nonexistent channel */
6108 if (c->type != CHAN_SOCKDATA_DORMANT)
6109 continue; /* dunno why they're failing this */
6110
e595953d 6111 reason_code = ssh_pkt_getuint32(ssh);
6112 if (reason_code >= lenof(reasons))
6113 reason_code = 0; /* ensure reasons[reason_code] in range */
6114 ssh_pkt_getstring(ssh, &reason_string, &reason_length);
6115 message = dupprintf("Forwarded connection refused by"
6116 " server: %s [%.*s]", reasons[reason_code],
6117 reason_length, reason_string);
6118 logevent(message);
6119 sfree(message);
724cface 6120
6121 pfd_close(c->u.pfd.s);
6122
51470298 6123 del234(ssh->channels, c);
724cface 6124 sfree(c);
51470298 6125 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_REQUEST) {
ebb0a590 6126 unsigned localid;
6127 char *type;
6128 int typelen, want_reply;
6129 struct ssh_channel *c;
6130
0016d70b 6131 localid = ssh_pkt_getuint32(ssh);
6132 ssh_pkt_getstring(ssh, &type, &typelen);
51470298 6133 want_reply = ssh2_pkt_getbool(ssh);
ebb0a590 6134
6135 /*
6136 * First, check that the channel exists. Otherwise,
6137 * we can instantly disconnect with a rude message.
6138 */
51470298 6139 c = find234(ssh->channels, &localid, ssh_channelfind);
ebb0a590 6140 if (!c) {
6141 char buf[80];
6142 sprintf(buf, "Received channel request for nonexistent"
6143 " channel %d", localid);
6144 logevent(buf);
51470298 6145 ssh2_pkt_init(ssh, SSH2_MSG_DISCONNECT);
6146 ssh2_pkt_adduint32(ssh, SSH2_DISCONNECT_BY_APPLICATION);
6147 ssh2_pkt_addstring(ssh, buf);
6148 ssh2_pkt_addstring(ssh, "en"); /* language tag */
6149 ssh2_pkt_send(ssh);
6b5cf8b4 6150 connection_fatal(ssh->frontend, "%s", buf);
3bb2f322 6151 ssh_closing((Plug)ssh, NULL, 0, 0);
7ffdbc1a 6152 crStopV;
ebb0a590 6153 }
6154
6155 /*
d8d6c7e5 6156 * Having got the channel number, we now look at
6157 * the request type string to see if it's something
6158 * we recognise.
ebb0a590 6159 */
d8d6c7e5 6160 if (typelen == 11 && !memcmp(type, "exit-status", 11) &&
51470298 6161 c == ssh->mainchan) {
d8d6c7e5 6162 /* We recognise "exit-status" on the primary channel. */
6163 char buf[100];
0016d70b 6164 ssh->exitcode = ssh_pkt_getuint32(ssh);
d8d6c7e5 6165 sprintf(buf, "Server sent command exit status %d",
51470298 6166 ssh->exitcode);
d8d6c7e5 6167 logevent(buf);
6168 if (want_reply) {
51470298 6169 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_SUCCESS);
6170 ssh2_pkt_adduint32(ssh, c->remoteid);
6171 ssh2_pkt_send(ssh);
d8d6c7e5 6172 }
6173 } else {
6174 /*
6175 * This is a channel request we don't know
6176 * about, so we now either ignore the request
6177 * or respond with CHANNEL_FAILURE, depending
6178 * on want_reply.
6179 */
6180 if (want_reply) {
51470298 6181 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_FAILURE);
6182 ssh2_pkt_adduint32(ssh, c->remoteid);
6183 ssh2_pkt_send(ssh);
d8d6c7e5 6184 }
ebb0a590 6185 }
51470298 6186 } else if (ssh->pktin.type == SSH2_MSG_GLOBAL_REQUEST) {
697d4856 6187 char *type;
6188 int typelen, want_reply;
6189
0016d70b 6190 ssh_pkt_getstring(ssh, &type, &typelen);
51470298 6191 want_reply = ssh2_pkt_getbool(ssh);
697d4856 6192
6193 /*
6194 * We currently don't support any global requests
6195 * at all, so we either ignore the request or
6196 * respond with REQUEST_FAILURE, depending on
6197 * want_reply.
6198 */
6199 if (want_reply) {
51470298 6200 ssh2_pkt_init(ssh, SSH2_MSG_REQUEST_FAILURE);
6201 ssh2_pkt_send(ssh);
697d4856 6202 }
51470298 6203 } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_OPEN) {
32874aea 6204 char *type;
6205 int typelen;
b3ebaa28 6206 char *peeraddr;
6207 int peeraddrlen;
2e5b14c0 6208 int peerport;
32874aea 6209 char *error = NULL;
6210 struct ssh_channel *c;
bc240b21 6211 unsigned remid, winsize, pktsize;
0016d70b 6212 ssh_pkt_getstring(ssh, &type, &typelen);
3d88e64d 6213 c = snew(struct ssh_channel);
51470298 6214 c->ssh = ssh;
32874aea 6215
0016d70b 6216 remid = ssh_pkt_getuint32(ssh);
6217 winsize = ssh_pkt_getuint32(ssh);
6218 pktsize = ssh_pkt_getuint32(ssh);
bc240b21 6219
32874aea 6220 if (typelen == 3 && !memcmp(type, "x11", 3)) {
df85f78b 6221 char *addrstr;
6222
0016d70b 6223 ssh_pkt_getstring(ssh, &peeraddr, &peeraddrlen);
df85f78b 6224 addrstr = snewn(peeraddrlen+1, char);
b3ebaa28 6225 memcpy(addrstr, peeraddr, peeraddrlen);
5a9bf764 6226 addrstr[peeraddrlen] = '\0';
0016d70b 6227 peerport = ssh_pkt_getuint32(ssh);
b3ebaa28 6228
5a9bf764 6229 logeventf(ssh, "Received X11 connect request from %s:%d",
6230 addrstr, peerport);
6231
51470298 6232 if (!ssh->X11_fwd_enabled)
32874aea 6233 error = "X11 forwarding is not enabled";
86916870 6234 else if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
2e5b14c0 6235 ssh->x11auth, addrstr, peerport,
e8fa8f62 6236 &ssh->cfg) != NULL) {
32874aea 6237 error = "Unable to open an X11 connection";
6238 } else {
5a9bf764 6239 logevent("Opening X11 forward connection succeeded");
32874aea 6240 c->type = CHAN_X11;
6241 }
b3ebaa28 6242
6243 sfree(addrstr);
bc240b21 6244 } else if (typelen == 15 &&
6245 !memcmp(type, "forwarded-tcpip", 15)) {
6246 struct ssh_rportfwd pf, *realpf;
6247 char *dummy;
6248 int dummylen;
0016d70b 6249 ssh_pkt_getstring(ssh, &dummy, &dummylen);/* skip address */
6250 pf.sport = ssh_pkt_getuint32(ssh);
6251 ssh_pkt_getstring(ssh, &peeraddr, &peeraddrlen);
6252 peerport = ssh_pkt_getuint32(ssh);
51470298 6253 realpf = find234(ssh->rportfwds, &pf, NULL);
5a9bf764 6254 logeventf(ssh, "Received remote port %d open request "
6255 "from %s:%d", pf.sport, peeraddr, peerport);
bc240b21 6256 if (realpf == NULL) {
6257 error = "Remote port is not recognised";
6258 } else {
cbe2d68f 6259 const char *e = pfd_newconnect(&c->u.pfd.s,
6260 realpf->dhost,
6261 realpf->dport, c,
6262 &ssh->cfg);
5a9bf764 6263 logeventf(ssh, "Attempting to forward remote port to "
6264 "%s:%d", realpf->dhost, realpf->dport);
bc240b21 6265 if (e != NULL) {
57356d63 6266 logeventf(ssh, "Port open failed: %s", e);
bc240b21 6267 error = "Port open failed";
6268 } else {
6269 logevent("Forwarded port opened successfully");
6270 c->type = CHAN_SOCKDATA;
6271 }
6272 }
32874aea 6273 } else if (typelen == 22 &&
36c2a3e9 6274 !memcmp(type, "auth-agent@openssh.com", 3)) {
51470298 6275 if (!ssh->agentfwd_enabled)
32874aea 6276 error = "Agent forwarding is not enabled";
36c2a3e9 6277 else {
32874aea 6278 c->type = CHAN_AGENT; /* identify channel type */
36c2a3e9 6279 c->u.a.lensofar = 0;
32874aea 6280 }
6281 } else {
6282 error = "Unsupported channel type requested";
6283 }
6284
bc240b21 6285 c->remoteid = remid;
32874aea 6286 if (error) {
51470298 6287 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_OPEN_FAILURE);
6288 ssh2_pkt_adduint32(ssh, c->remoteid);
6289 ssh2_pkt_adduint32(ssh, SSH2_OPEN_CONNECT_FAILED);
6290 ssh2_pkt_addstring(ssh, error);
6291 ssh2_pkt_addstring(ssh, "en"); /* language tag */
6292 ssh2_pkt_send(ssh);
5a9bf764 6293 logeventf(ssh, "Rejected channel open: %s", error);
32874aea 6294 sfree(c);
6295 } else {
51470298 6296 c->localid = alloc_channel_id(ssh);
32874aea 6297 c->closes = 0;
5471d09a 6298 c->v.v2.locwindow = OUR_V2_WINSIZE;
6299 c->v.v2.remwindow = winsize;
6300 c->v.v2.remmaxpkt = pktsize;
6301 bufchain_init(&c->v.v2.outbuffer);
51470298 6302 add234(ssh->channels, c);
6303 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
6304 ssh2_pkt_adduint32(ssh, c->remoteid);
6305 ssh2_pkt_adduint32(ssh, c->localid);
6306 ssh2_pkt_adduint32(ssh, c->v.v2.locwindow);
6307 ssh2_pkt_adduint32(ssh, 0x4000UL); /* our max pkt size */
6308 ssh2_pkt_send(ssh);
32874aea 6309 }
7cca0d81 6310 } else {
6b5cf8b4 6311 bombout(("Strange packet received: type %d", ssh->pktin.type));
7ffdbc1a 6312 crStopV;
7cca0d81 6313 }
6314 } else {
32874aea 6315 /*
6316 * We have spare data. Add it to the channel buffer.
6317 */
d8baa528 6318 ssh2_add_channel_data(ssh->mainchan, (char *)in, inlen);
51470298 6319 s->try_send = TRUE;
32874aea 6320 }
51470298 6321 if (s->try_send) {
32874aea 6322 int i;
6323 struct ssh_channel *c;
6324 /*
6325 * Try to send data on all channels if we can.
6326 */
51470298 6327 for (i = 0; NULL != (c = index234(ssh->channels, i)); i++) {
a6253970 6328 int bufsize;
6329 if (c->closes)
6330 continue; /* don't send on closing channels */
6331 bufsize = ssh2_try_send(c);
5471d09a 6332 if (bufsize == 0) {
6333 switch (c->type) {
6334 case CHAN_MAINSESSION:
6335 /* stdin need not receive an unthrottle
6336 * notification since it will be polled */
6337 break;
6338 case CHAN_X11:
6339 x11_unthrottle(c->u.x11.s);
6340 break;
6341 case CHAN_AGENT:
6342 /* agent sockets are request/response and need no
6343 * buffer management */
6344 break;
6345 case CHAN_SOCKDATA:
6346 pfd_unthrottle(c->u.pfd.s);
6347 break;
6348 }
6349 }
6350 }
7cca0d81 6351 }
e5574168 6352 }
6353
6354 crFinishV;
6355}
6356
6357/*
7cca0d81 6358 * Handle the top-level SSH2 protocol.
6359 */
51470298 6360static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
7cca0d81 6361{
51470298 6362 if (do_ssh2_transport(ssh, in, inlen, ispkt) == 0)
32874aea 6363 return;
51470298 6364 do_ssh2_authconn(ssh, in, inlen, ispkt);
7cca0d81 6365}
6366
6367/*
8df7a775 6368 * Called to set up the connection.
374330e2 6369 *
6370 * Returns an error message, or NULL on success.
374330e2 6371 */
cbe2d68f 6372static const char *ssh_init(void *frontend_handle, void **backend_handle,
6373 Config *cfg,
79bf227b 6374 char *host, int port, char **realhost, int nodelay,
6375 int keepalive)
32874aea 6376{
cbe2d68f 6377 const char *p;
51470298 6378 Ssh ssh;
6379
3d88e64d 6380 ssh = snew(struct ssh_tag);
86916870 6381 ssh->cfg = *cfg; /* STRUCTURE COPY */
125105d1 6382 ssh->version = 0; /* when not ready yet */
51470298 6383 ssh->s = NULL;
6384 ssh->cipher = NULL;
371e569c 6385 ssh->v1_cipher_ctx = NULL;
0183b242 6386 ssh->crcda_ctx = NULL;
51470298 6387 ssh->cscipher = NULL;
371e569c 6388 ssh->cs_cipher_ctx = NULL;
51470298 6389 ssh->sccipher = NULL;
371e569c 6390 ssh->sc_cipher_ctx = NULL;
51470298 6391 ssh->csmac = NULL;
a8327734 6392 ssh->cs_mac_ctx = NULL;
51470298 6393 ssh->scmac = NULL;
e0e1a00d 6394 ssh->sc_mac_ctx = NULL;
51470298 6395 ssh->cscomp = NULL;
5366aed8 6396 ssh->cs_comp_ctx = NULL;
51470298 6397 ssh->sccomp = NULL;
5366aed8 6398 ssh->sc_comp_ctx = NULL;
51470298 6399 ssh->kex = NULL;
389aa499 6400 ssh->kex_ctx = NULL;
51470298 6401 ssh->hostkey = NULL;
6402 ssh->exitcode = -1;
6403 ssh->state = SSH_STATE_PREPACKET;
6404 ssh->size_needed = FALSE;
6405 ssh->eof_needed = FALSE;
b9d7bcad 6406 ssh->ldisc = NULL;
a8327734 6407 ssh->logctx = NULL;
51470298 6408 {
6409 static const struct Packet empty = { 0, 0, NULL, NULL, 0 };
6410 ssh->pktin = ssh->pktout = empty;
6411 }
6412 ssh->deferred_send_data = NULL;
6413 ssh->deferred_len = 0;
6414 ssh->deferred_size = 0;
6415 ssh->fallback_cmd = 0;
6416 ssh->pkt_ctx = 0;
302121de 6417 ssh->x11auth = NULL;
be738459 6418 ssh->v1_compressing = FALSE;
51470298 6419 ssh->v2_outgoing_sequence = 0;
6420 ssh->ssh1_rdpkt_crstate = 0;
6421 ssh->ssh2_rdpkt_crstate = 0;
6422 ssh->do_ssh_init_crstate = 0;
6423 ssh->ssh_gotdata_crstate = 0;
6424 ssh->ssh1_protocol_crstate = 0;
6425 ssh->do_ssh1_login_crstate = 0;
6426 ssh->do_ssh2_transport_crstate = 0;
6427 ssh->do_ssh2_authconn_crstate = 0;
6428 ssh->do_ssh_init_state = NULL;
6429 ssh->do_ssh1_login_state = NULL;
6430 ssh->do_ssh2_transport_state = NULL;
6431 ssh->do_ssh2_authconn_state = NULL;
6571dbfd 6432 ssh->mainchan = NULL;
968d2d92 6433 ssh->throttled_all = 0;
6434 ssh->v1_stdout_throttling = 0;
51470298 6435
6436 *backend_handle = ssh;
32874aea 6437
8f203108 6438#ifdef MSCRYPTOAPI
32874aea 6439 if (crypto_startup() == 0)
8f203108 6440 return "Microsoft high encryption pack not installed!";
6441#endif
374330e2 6442
51470298 6443 ssh->frontend = frontend_handle;
86916870 6444 ssh->term_width = ssh->cfg.width;
6445 ssh->term_height = ssh->cfg.height;
887035a5 6446
fabd1805 6447 ssh->channels = NULL;
6448 ssh->rportfwds = NULL;
6449
51470298 6450 ssh->send_ok = 0;
6451 ssh->editing = 0;
6452 ssh->echoing = 0;
6453 ssh->v1_throttle_count = 0;
6454 ssh->overall_bufsize = 0;
6455 ssh->fallback_cmd = 0;
8df7a775 6456
3648d4c5 6457 ssh->protocol = NULL;
6458
79bf227b 6459 p = connect_to_host(ssh, host, port, realhost, nodelay, keepalive);
fb09bf1c 6460 if (p != NULL)
6461 return p;
374330e2 6462
374330e2 6463 return NULL;
6464}
6465
fabd1805 6466static void ssh_free(void *handle)
6467{
6468 Ssh ssh = (Ssh) handle;
6469 struct ssh_channel *c;
6470 struct ssh_rportfwd *pf;
6471
6472 if (ssh->v1_cipher_ctx)
6473 ssh->cipher->free_context(ssh->v1_cipher_ctx);
6474 if (ssh->cs_cipher_ctx)
6475 ssh->cscipher->free_context(ssh->cs_cipher_ctx);
6476 if (ssh->sc_cipher_ctx)
6477 ssh->sccipher->free_context(ssh->sc_cipher_ctx);
6478 if (ssh->cs_mac_ctx)
6479 ssh->csmac->free_context(ssh->cs_mac_ctx);
6480 if (ssh->sc_mac_ctx)
6481 ssh->scmac->free_context(ssh->sc_mac_ctx);
29b1d0b3 6482 if (ssh->cs_comp_ctx) {
6483 if (ssh->cscomp)
6484 ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
6485 else
6486 zlib_compress_cleanup(ssh->cs_comp_ctx);
6487 }
6488 if (ssh->sc_comp_ctx) {
6489 if (ssh->sccomp)
6490 ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
6491 else
6492 zlib_decompress_cleanup(ssh->sc_comp_ctx);
6493 }
fabd1805 6494 if (ssh->kex_ctx)
6495 dh_cleanup(ssh->kex_ctx);
6496 sfree(ssh->savedhost);
6497
6498 if (ssh->channels) {
6499 while ((c = delpos234(ssh->channels, 0)) != NULL) {
6500 switch (c->type) {
6501 case CHAN_X11:
6502 if (c->u.x11.s != NULL)
6503 x11_close(c->u.x11.s);
6504 break;
6505 case CHAN_SOCKDATA:
6506 if (c->u.pfd.s != NULL)
6507 pfd_close(c->u.pfd.s);
6508 break;
6509 }
6510 sfree(c);
6511 }
6512 freetree234(ssh->channels);
6513 }
6514
6515 if (ssh->rportfwds) {
6516 while ((pf = delpos234(ssh->rportfwds, 0)) != NULL)
6517 sfree(pf);
6518 freetree234(ssh->rportfwds);
6519 }
6520 sfree(ssh->deferred_send_data);
6521 if (ssh->x11auth)
6522 x11_free_auth(ssh->x11auth);
6523 sfree(ssh->do_ssh_init_state);
6524 sfree(ssh->do_ssh1_login_state);
6525 sfree(ssh->do_ssh2_transport_state);
6526 sfree(ssh->do_ssh2_authconn_state);
679539d7 6527 if (ssh->pktout.data) {
6528 sfree(ssh->pktout.data);
6529 ssh->pktout.data = NULL;
6530 }
6531 if (ssh->pktin.data) {
6532 sfree(ssh->pktin.data);
6533 ssh->pktin.data = NULL;
6534 }
6535 if (ssh->crcda_ctx) {
6536 crcda_free_context(ssh->crcda_ctx);
6537 ssh->crcda_ctx = NULL;
6538 }
fabd1805 6539 if (ssh->s)
36f94d1f 6540 ssh_do_close(ssh);
fabd1805 6541 sfree(ssh);
6542}
6543
374330e2 6544/*
86916870 6545 * Reconfigure the SSH backend.
6546 *
6547 * Currently, this function does nothing very useful. In future,
6548 * however, we could do some handy things with it. For example, we
6549 * could make the port forwarding configurer active in the Change
6550 * Settings box, and this routine could close down existing
6551 * forwardings and open up new ones in response to changes.
6552 */
6553static void ssh_reconfig(void *handle, Config *cfg)
6554{
6555 Ssh ssh = (Ssh) handle;
6556 ssh->cfg = *cfg; /* STRUCTURE COPY */
6557}
6558
6559/*
374330e2 6560 * Called to send data down the Telnet connection.
6561 */
51470298 6562static int ssh_send(void *handle, char *buf, int len)
32874aea 6563{
51470298 6564 Ssh ssh = (Ssh) handle;
6565
6566 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
5471d09a 6567 return 0;
374330e2 6568
d8baa528 6569 ssh->protocol(ssh, (unsigned char *)buf, len, 0);
5471d09a 6570
51470298 6571 return ssh_sendbuffer(ssh);
5471d09a 6572}
6573
6574/*
6575 * Called to query the current amount of buffered stdin data.
6576 */
51470298 6577static int ssh_sendbuffer(void *handle)
5471d09a 6578{
51470298 6579 Ssh ssh = (Ssh) handle;
5471d09a 6580 int override_value;
6581
51470298 6582 if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
5471d09a 6583 return 0;
6584
6585 /*
6586 * If the SSH socket itself has backed up, add the total backup
6587 * size on that to any individual buffer on the stdin channel.
6588 */
6589 override_value = 0;
51470298 6590 if (ssh->throttled_all)
6591 override_value = ssh->overall_bufsize;
5471d09a 6592
51470298 6593 if (ssh->version == 1) {
5471d09a 6594 return override_value;
51470298 6595 } else if (ssh->version == 2) {
6596 if (!ssh->mainchan || ssh->mainchan->closes > 0)
5471d09a 6597 return override_value;
6598 else
51470298 6599 return (override_value +
6600 bufchain_size(&ssh->mainchan->v.v2.outbuffer));
5471d09a 6601 }
6602
6603 return 0;
374330e2 6604}
6605
6606/*
6e48c3fe 6607 * Called to set the size of the window from SSH's POV.
374330e2 6608 */
51470298 6609static void ssh_size(void *handle, int width, int height)
32874aea 6610{
51470298 6611 Ssh ssh = (Ssh) handle;
6612
6613 ssh->term_width = width;
6614 ssh->term_height = height;
f278d6f8 6615
51470298 6616 switch (ssh->state) {
374330e2 6617 case SSH_STATE_BEFORE_SIZE:
3687d221 6618 case SSH_STATE_PREPACKET:
21248260 6619 case SSH_STATE_CLOSED:
374330e2 6620 break; /* do nothing */
6621 case SSH_STATE_INTERMED:
51470298 6622 ssh->size_needed = TRUE; /* buffer for later */
374330e2 6623 break;
6624 case SSH_STATE_SESSION:
86916870 6625 if (!ssh->cfg.nopty) {
51470298 6626 if (ssh->version == 1) {
6627 send_packet(ssh, SSH1_CMSG_WINDOW_SIZE,
6628 PKT_INT, ssh->term_height,
6629 PKT_INT, ssh->term_width,
32874aea 6630 PKT_INT, 0, PKT_INT, 0, PKT_END);
6631 } else {
51470298 6632 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
6633 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
6634 ssh2_pkt_addstring(ssh, "window-change");
6635 ssh2_pkt_addbool(ssh, 0);
6636 ssh2_pkt_adduint32(ssh, ssh->term_width);
6637 ssh2_pkt_adduint32(ssh, ssh->term_height);
6638 ssh2_pkt_adduint32(ssh, 0);
6639 ssh2_pkt_adduint32(ssh, 0);
6640 ssh2_pkt_send(ssh);
32874aea 6641 }
6642 }
6643 break;
374330e2 6644 }
6645}
6646
6647/*
125105d1 6648 * Return a list of the special codes that make sense in this
6649 * protocol.
6650 */
6651static const struct telnet_special *ssh_get_specials(void *handle)
6652{
6653 Ssh ssh = (Ssh) handle;
6654
6655 if (ssh->version == 1) {
6656 static const struct telnet_special ssh1_specials[] = {
6657 {"IGNORE message", TS_NOP},
6658 {NULL, 0}
6659 };
6660 return ssh1_specials;
6661 } else if (ssh->version == 2) {
6662 static const struct telnet_special ssh2_specials[] = {
6663 {"Break", TS_BRK},
6664 {"IGNORE message", TS_NOP},
6665 {NULL, 0}
6666 };
6667 return ssh2_specials;
6668 } else
6669 return NULL;
6670}
6671
6672/*
6abbf9e3 6673 * Send Telnet special codes. TS_EOF is useful for `plink', so you
6674 * can send an EOF and collect resulting output (e.g. `plink
6675 * hostname sort').
374330e2 6676 */
51470298 6677static void ssh_special(void *handle, Telnet_Special code)
32874aea 6678{
51470298 6679 Ssh ssh = (Ssh) handle;
6680
6abbf9e3 6681 if (code == TS_EOF) {
51470298 6682 if (ssh->state != SSH_STATE_SESSION) {
32874aea 6683 /*
6684 * Buffer the EOF in case we are pre-SESSION, so we can
6685 * send it as soon as we reach SESSION.
6686 */
6687 if (code == TS_EOF)
51470298 6688 ssh->eof_needed = TRUE;
32874aea 6689 return;
6690 }
51470298 6691 if (ssh->version == 1) {
6692 send_packet(ssh, SSH1_CMSG_EOF, PKT_END);
32874aea 6693 } else {
51470298 6694 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_EOF);
6695 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
6696 ssh2_pkt_send(ssh);
32874aea 6697 }
6698 logevent("Sent EOF message");
125105d1 6699 } else if (code == TS_PING || code == TS_NOP) {
51470298 6700 if (ssh->state == SSH_STATE_CLOSED
6701 || ssh->state == SSH_STATE_PREPACKET) return;
6702 if (ssh->version == 1) {
6703 if (!(ssh->remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE))
6704 send_packet(ssh, SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
32874aea 6705 } else {
51470298 6706 ssh2_pkt_init(ssh, SSH2_MSG_IGNORE);
6707 ssh2_pkt_addstring_start(ssh);
6708 ssh2_pkt_send(ssh);
32874aea 6709 }
125105d1 6710 } else if (code == TS_BRK) {
6711 if (ssh->state == SSH_STATE_CLOSED
6712 || ssh->state == SSH_STATE_PREPACKET) return;
6713 if (ssh->version == 1) {
6714 logevent("Unable to send BREAK signal in SSH1");
6715 } else {
6716 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
6717 ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
6718 ssh2_pkt_addstring(ssh, "break");
6719 ssh2_pkt_addbool(ssh, 0);
6720 ssh2_pkt_adduint32(ssh, 0); /* default break length */
6721 ssh2_pkt_send(ssh);
6722 }
6abbf9e3 6723 } else {
32874aea 6724 /* do nothing */
6abbf9e3 6725 }
374330e2 6726}
6727
51470298 6728void *new_sock_channel(void *handle, Socket s)
d74d141c 6729{
51470298 6730 Ssh ssh = (Ssh) handle;
d74d141c 6731 struct ssh_channel *c;
3d88e64d 6732 c = snew(struct ssh_channel);
51470298 6733 c->ssh = ssh;
d74d141c 6734
6735 if (c) {
bc240b21 6736 c->remoteid = -1; /* to be set when open confirmed */
51470298 6737 c->localid = alloc_channel_id(ssh);
d74d141c 6738 c->closes = 0;
bc240b21 6739 c->type = CHAN_SOCKDATA_DORMANT;/* identify channel type */
d74d141c 6740 c->u.pfd.s = s;
013dd8c0 6741 bufchain_init(&c->v.v2.outbuffer);
51470298 6742 add234(ssh->channels, c);
d74d141c 6743 }
6744 return c;
6745}
6746
5471d09a 6747/*
6748 * This is called when stdout/stderr (the entity to which
6749 * from_backend sends data) manages to clear some backlog.
6750 */
ae9ae89f 6751static void ssh_unthrottle(void *handle, int bufsize)
5471d09a 6752{
51470298 6753 Ssh ssh = (Ssh) handle;
6754 if (ssh->version == 1) {
6755 if (ssh->v1_stdout_throttling && bufsize < SSH1_BUFFER_LIMIT) {
6756 ssh->v1_stdout_throttling = 0;
6757 ssh1_throttle(ssh, -1);
5471d09a 6758 }
6759 } else {
51470298 6760 if (ssh->mainchan && ssh->mainchan->closes == 0)
6761 ssh2_set_window(ssh->mainchan, OUR_V2_WINSIZE - bufsize);
5471d09a 6762 }
6763}
6764
6b78788a 6765void ssh_send_port_open(void *channel, char *hostname, int port, char *org)
d74d141c 6766{
6767 struct ssh_channel *c = (struct ssh_channel *)channel;
6b78788a 6768 Ssh ssh = c->ssh;
d74d141c 6769
57356d63 6770 logeventf(ssh, "Opening forwarded connection to %s:%d", hostname, port);
d74d141c 6771
51470298 6772 if (ssh->version == 1) {
6773 send_packet(ssh, SSH1_MSG_PORT_OPEN,
bc240b21 6774 PKT_INT, c->localid,
6775 PKT_STR, hostname,
6776 PKT_INT, port,
6777 //PKT_STR, <org:orgport>,
6778 PKT_END);
6779 } else {
51470298 6780 ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_OPEN);
6781 ssh2_pkt_addstring(ssh, "direct-tcpip");
6782 ssh2_pkt_adduint32(ssh, c->localid);
5471d09a 6783 c->v.v2.locwindow = OUR_V2_WINSIZE;
51470298 6784 ssh2_pkt_adduint32(ssh, c->v.v2.locwindow);/* our window size */
6785 ssh2_pkt_adduint32(ssh, 0x4000UL); /* our max pkt size */
6786 ssh2_pkt_addstring(ssh, hostname);
6787 ssh2_pkt_adduint32(ssh, port);
bc240b21 6788 /*
6789 * We make up values for the originator data; partly it's
6790 * too much hassle to keep track, and partly I'm not
6791 * convinced the server should be told details like that
6792 * about my local network configuration.
6793 */
51470298 6794 ssh2_pkt_addstring(ssh, "client-side-connection");
6795 ssh2_pkt_adduint32(ssh, 0);
6796 ssh2_pkt_send(ssh);
bc240b21 6797 }
d74d141c 6798}
6799
6800
51470298 6801static Socket ssh_socket(void *handle)
32874aea 6802{
51470298 6803 Ssh ssh = (Ssh) handle;
6804 return ssh->s;
32874aea 6805}
8ccc75b0 6806
51470298 6807static int ssh_sendok(void *handle)
32874aea 6808{
51470298 6809 Ssh ssh = (Ssh) handle;
6810 return ssh->send_ok;
32874aea 6811}
fb09bf1c 6812
51470298 6813static int ssh_ldisc(void *handle, int option)
32874aea 6814{
51470298 6815 Ssh ssh = (Ssh) handle;
32874aea 6816 if (option == LD_ECHO)
51470298 6817 return ssh->echoing;
32874aea 6818 if (option == LD_EDIT)
51470298 6819 return ssh->editing;
0965bee0 6820 return FALSE;
6821}
6822
b9d7bcad 6823static void ssh_provide_ldisc(void *handle, void *ldisc)
6824{
6825 Ssh ssh = (Ssh) handle;
6826 ssh->ldisc = ldisc;
6827}
6828
a8327734 6829static void ssh_provide_logctx(void *handle, void *logctx)
6830{
6831 Ssh ssh = (Ssh) handle;
6832 ssh->logctx = logctx;
6833}
6834
51470298 6835static int ssh_return_exitcode(void *handle)
6836{
6837 Ssh ssh = (Ssh) handle;
3bb2f322 6838 if (ssh->s != NULL)
6839 return -1;
6840 else
6841 return (ssh->exitcode >= 0 ? ssh->exitcode : 0);
51470298 6842}
6843
6844/*
6845 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
6846 * that fails. This variable is the means by which scp.c can reach
6847 * into the SSH code and find out which one it got.
6848 */
6849extern int ssh_fallback_cmd(void *handle)
d8d6c7e5 6850{
51470298 6851 Ssh ssh = (Ssh) handle;
6852 return ssh->fallback_cmd;
d8d6c7e5 6853}
6854
374330e2 6855Backend ssh_backend = {
6856 ssh_init,
fabd1805 6857 ssh_free,
86916870 6858 ssh_reconfig,
374330e2 6859 ssh_send,
5471d09a 6860 ssh_sendbuffer,
374330e2 6861 ssh_size,
4017be6d 6862 ssh_special,
125105d1 6863 ssh_get_specials,
8ccc75b0 6864 ssh_socket,
d8d6c7e5 6865 ssh_return_exitcode,
97db3be4 6866 ssh_sendok,
0965bee0 6867 ssh_ldisc,
b9d7bcad 6868 ssh_provide_ldisc,
a8327734 6869 ssh_provide_logctx,
5471d09a 6870 ssh_unthrottle,
97db3be4 6871 22
bc240b21 6872};
Local modifications for Simon Tatham's `PuTTY' SSH client and terminal emulator