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Fix AltGr/Application/Compose/CtrlAlt discrepancies introduced in windlg.c
[u/mdw/putty] / ssh.c
CommitLineData
8df7a775 1#include <windows.h>
374330e2 2#include <stdio.h>
3#include <stdlib.h>
fb09bf1c 4#include <stdarg.h>
5#include <assert.h>
374330e2 6
7#include "putty.h"
dacbd0e8 8#include "tree234.h"
fb09bf1c 9#include "ssh.h"
374330e2 10
11#ifndef FALSE
12#define FALSE 0
13#endif
14#ifndef TRUE
15#define TRUE 1
16#endif
17
fb09bf1c 18#define logevent(s) { logevent(s); \
67779be7 19 if ((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)) \
b4453f49 20 { fprintf(stderr, "%s\n", s); fflush(stderr); } }
fb09bf1c 21
247308b5 22/* logevent, only printf-formatted. */
23void logeventf(char *fmt, ...)
24{
25 va_list ap;
26 char stuff[200];
27
28 va_start(ap, fmt);
29 vsprintf(stuff, fmt, ap);
30 va_end(ap);
31 logevent(stuff);
32}
33
3cd52910 34#define bombout(msg) ( ssh_state = SSH_STATE_CLOSED, \
4a8fc3c4 35 (s ? sk_close(s), s = NULL : 0), \
247308b5 36 logeventf msg, connection_fatal msg )
8d5de777 37
32874aea 38#define SSH1_MSG_DISCONNECT 1 /* 0x1 */
39#define SSH1_SMSG_PUBLIC_KEY 2 /* 0x2 */
40#define SSH1_CMSG_SESSION_KEY 3 /* 0x3 */
41#define SSH1_CMSG_USER 4 /* 0x4 */
42#define SSH1_CMSG_AUTH_RSA 6 /* 0x6 */
43#define SSH1_SMSG_AUTH_RSA_CHALLENGE 7 /* 0x7 */
44#define SSH1_CMSG_AUTH_RSA_RESPONSE 8 /* 0x8 */
45#define SSH1_CMSG_AUTH_PASSWORD 9 /* 0x9 */
46#define SSH1_CMSG_REQUEST_PTY 10 /* 0xa */
47#define SSH1_CMSG_WINDOW_SIZE 11 /* 0xb */
48#define SSH1_CMSG_EXEC_SHELL 12 /* 0xc */
49#define SSH1_CMSG_EXEC_CMD 13 /* 0xd */
50#define SSH1_SMSG_SUCCESS 14 /* 0xe */
51#define SSH1_SMSG_FAILURE 15 /* 0xf */
52#define SSH1_CMSG_STDIN_DATA 16 /* 0x10 */
53#define SSH1_SMSG_STDOUT_DATA 17 /* 0x11 */
54#define SSH1_SMSG_STDERR_DATA 18 /* 0x12 */
55#define SSH1_CMSG_EOF 19 /* 0x13 */
56#define SSH1_SMSG_EXIT_STATUS 20 /* 0x14 */
57#define SSH1_MSG_CHANNEL_OPEN_CONFIRMATION 21 /* 0x15 */
58#define SSH1_MSG_CHANNEL_OPEN_FAILURE 22 /* 0x16 */
59#define SSH1_MSG_CHANNEL_DATA 23 /* 0x17 */
60#define SSH1_MSG_CHANNEL_CLOSE 24 /* 0x18 */
61#define SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION 25 /* 0x19 */
62#define SSH1_SMSG_X11_OPEN 27 /* 0x1b */
63#define SSH1_CMSG_PORT_FORWARD_REQUEST 28 /* 0x1c */
64#define SSH1_MSG_PORT_OPEN 29 /* 0x1d */
65#define SSH1_CMSG_AGENT_REQUEST_FORWARDING 30 /* 0x1e */
66#define SSH1_SMSG_AGENT_OPEN 31 /* 0x1f */
67#define SSH1_MSG_IGNORE 32 /* 0x20 */
68#define SSH1_CMSG_EXIT_CONFIRMATION 33 /* 0x21 */
69#define SSH1_CMSG_X11_REQUEST_FORWARDING 34 /* 0x22 */
70#define SSH1_CMSG_AUTH_RHOSTS_RSA 35 /* 0x23 */
71#define SSH1_MSG_DEBUG 36 /* 0x24 */
72#define SSH1_CMSG_REQUEST_COMPRESSION 37 /* 0x25 */
73#define SSH1_CMSG_AUTH_TIS 39 /* 0x27 */
74#define SSH1_SMSG_AUTH_TIS_CHALLENGE 40 /* 0x28 */
75#define SSH1_CMSG_AUTH_TIS_RESPONSE 41 /* 0x29 */
76#define SSH1_CMSG_AUTH_CCARD 70 /* 0x46 */
77#define SSH1_SMSG_AUTH_CCARD_CHALLENGE 71 /* 0x47 */
78#define SSH1_CMSG_AUTH_CCARD_RESPONSE 72 /* 0x48 */
79
80#define SSH1_AUTH_TIS 5 /* 0x5 */
81#define SSH1_AUTH_CCARD 16 /* 0x10 */
82
83#define SSH1_PROTOFLAG_SCREEN_NUMBER 1 /* 0x1 */
b96dc54c 84/* Mask for protoflags we will echo back to server if seen */
32874aea 85#define SSH1_PROTOFLAGS_SUPPORTED 0 /* 0x1 */
86
87#define SSH2_MSG_DISCONNECT 1 /* 0x1 */
88#define SSH2_MSG_IGNORE 2 /* 0x2 */
89#define SSH2_MSG_UNIMPLEMENTED 3 /* 0x3 */
90#define SSH2_MSG_DEBUG 4 /* 0x4 */
91#define SSH2_MSG_SERVICE_REQUEST 5 /* 0x5 */
92#define SSH2_MSG_SERVICE_ACCEPT 6 /* 0x6 */
93#define SSH2_MSG_KEXINIT 20 /* 0x14 */
94#define SSH2_MSG_NEWKEYS 21 /* 0x15 */
95#define SSH2_MSG_KEXDH_INIT 30 /* 0x1e */
96#define SSH2_MSG_KEXDH_REPLY 31 /* 0x1f */
97#define SSH2_MSG_KEX_DH_GEX_REQUEST 30 /* 0x1e */
98#define SSH2_MSG_KEX_DH_GEX_GROUP 31 /* 0x1f */
99#define SSH2_MSG_KEX_DH_GEX_INIT 32 /* 0x20 */
100#define SSH2_MSG_KEX_DH_GEX_REPLY 33 /* 0x21 */
101#define SSH2_MSG_USERAUTH_REQUEST 50 /* 0x32 */
102#define SSH2_MSG_USERAUTH_FAILURE 51 /* 0x33 */
103#define SSH2_MSG_USERAUTH_SUCCESS 52 /* 0x34 */
104#define SSH2_MSG_USERAUTH_BANNER 53 /* 0x35 */
105#define SSH2_MSG_USERAUTH_PK_OK 60 /* 0x3c */
106#define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60 /* 0x3c */
761187b6 107#define SSH2_MSG_USERAUTH_INFO_REQUEST 60 /* 0x3c */
108#define SSH2_MSG_USERAUTH_INFO_RESPONSE 61 /* 0x3d */
32874aea 109#define SSH2_MSG_GLOBAL_REQUEST 80 /* 0x50 */
110#define SSH2_MSG_REQUEST_SUCCESS 81 /* 0x51 */
111#define SSH2_MSG_REQUEST_FAILURE 82 /* 0x52 */
112#define SSH2_MSG_CHANNEL_OPEN 90 /* 0x5a */
113#define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91 /* 0x5b */
114#define SSH2_MSG_CHANNEL_OPEN_FAILURE 92 /* 0x5c */
115#define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93 /* 0x5d */
116#define SSH2_MSG_CHANNEL_DATA 94 /* 0x5e */
117#define SSH2_MSG_CHANNEL_EXTENDED_DATA 95 /* 0x5f */
118#define SSH2_MSG_CHANNEL_EOF 96 /* 0x60 */
119#define SSH2_MSG_CHANNEL_CLOSE 97 /* 0x61 */
120#define SSH2_MSG_CHANNEL_REQUEST 98 /* 0x62 */
121#define SSH2_MSG_CHANNEL_SUCCESS 99 /* 0x63 */
122#define SSH2_MSG_CHANNEL_FAILURE 100 /* 0x64 */
123
00db133f 124/*
125 * Packet type contexts, so that ssh2_pkt_type can correctly decode
126 * the ambiguous type numbers back into the correct type strings.
127 */
128#define SSH2_PKTCTX_DHGROUP1 0x0001
129#define SSH2_PKTCTX_DHGEX 0x0002
130#define SSH2_PKTCTX_PUBLICKEY 0x0010
131#define SSH2_PKTCTX_PASSWORD 0x0020
132#define SSH2_PKTCTX_KBDINTER 0x0040
133#define SSH2_PKTCTX_AUTH_MASK 0x00F0
134
32874aea 135#define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1 /* 0x1 */
136#define SSH2_DISCONNECT_PROTOCOL_ERROR 2 /* 0x2 */
137#define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3 /* 0x3 */
138#define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4 /* 0x4 */
139#define SSH2_DISCONNECT_MAC_ERROR 5 /* 0x5 */
140#define SSH2_DISCONNECT_COMPRESSION_ERROR 6 /* 0x6 */
141#define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7 /* 0x7 */
142#define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8 /* 0x8 */
143#define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9 /* 0x9 */
144#define SSH2_DISCONNECT_CONNECTION_LOST 10 /* 0xa */
145#define SSH2_DISCONNECT_BY_APPLICATION 11 /* 0xb */
146#define SSH2_DISCONNECT_TOO_MANY_CONNECTIONS 12 /* 0xc */
147#define SSH2_DISCONNECT_AUTH_CANCELLED_BY_USER 13 /* 0xd */
148#define SSH2_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE 14 /* 0xe */
149#define SSH2_DISCONNECT_ILLEGAL_USER_NAME 15 /* 0xf */
38c4a8da 150
151static const char *const ssh2_disconnect_reasons[] = {
152 NULL,
153 "SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT",
154 "SSH_DISCONNECT_PROTOCOL_ERROR",
155 "SSH_DISCONNECT_KEY_EXCHANGE_FAILED",
156 "SSH_DISCONNECT_HOST_AUTHENTICATION_FAILED",
157 "SSH_DISCONNECT_MAC_ERROR",
158 "SSH_DISCONNECT_COMPRESSION_ERROR",
159 "SSH_DISCONNECT_SERVICE_NOT_AVAILABLE",
160 "SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED",
161 "SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE",
162 "SSH_DISCONNECT_CONNECTION_LOST",
163 "SSH_DISCONNECT_BY_APPLICATION",
164 "SSH_DISCONNECT_TOO_MANY_CONNECTIONS",
165 "SSH_DISCONNECT_AUTH_CANCELLED_BY_USER",
166 "SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE",
167 "SSH_DISCONNECT_ILLEGAL_USER_NAME",
168};
9005f3ba 169
32874aea 170#define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1 /* 0x1 */
171#define SSH2_OPEN_CONNECT_FAILED 2 /* 0x2 */
172#define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3 /* 0x3 */
173#define SSH2_OPEN_RESOURCE_SHORTAGE 4 /* 0x4 */
d211621f 174
32874aea 175#define SSH2_EXTENDED_DATA_STDERR 1 /* 0x1 */
fb09bf1c 176
7d503c31 177/*
178 * Various remote-bug flags.
179 */
180#define BUG_CHOKES_ON_SSH1_IGNORE 1
181#define BUG_SSH2_HMAC 2
bd358db1 182#define BUG_NEEDS_SSH1_PLAIN_PASSWORD 4
0df73905 183#define BUG_CHOKES_ON_RSA 8
bd358db1 184
00db133f 185static int ssh_pkt_ctx = 0;
186
187#define translate(x) if (type == x) return #x
188#define translatec(x,ctx) if (type == x && (ssh_pkt_ctx & ctx)) return #x
189char *ssh1_pkt_type(int type)
190{
191 translate(SSH1_MSG_DISCONNECT);
192 translate(SSH1_SMSG_PUBLIC_KEY);
193 translate(SSH1_CMSG_SESSION_KEY);
194 translate(SSH1_CMSG_USER);
195 translate(SSH1_CMSG_AUTH_RSA);
196 translate(SSH1_SMSG_AUTH_RSA_CHALLENGE);
197 translate(SSH1_CMSG_AUTH_RSA_RESPONSE);
198 translate(SSH1_CMSG_AUTH_PASSWORD);
199 translate(SSH1_CMSG_REQUEST_PTY);
200 translate(SSH1_CMSG_WINDOW_SIZE);
201 translate(SSH1_CMSG_EXEC_SHELL);
202 translate(SSH1_CMSG_EXEC_CMD);
203 translate(SSH1_SMSG_SUCCESS);
204 translate(SSH1_SMSG_FAILURE);
205 translate(SSH1_CMSG_STDIN_DATA);
206 translate(SSH1_SMSG_STDOUT_DATA);
207 translate(SSH1_SMSG_STDERR_DATA);
208 translate(SSH1_CMSG_EOF);
209 translate(SSH1_SMSG_EXIT_STATUS);
210 translate(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION);
211 translate(SSH1_MSG_CHANNEL_OPEN_FAILURE);
212 translate(SSH1_MSG_CHANNEL_DATA);
213 translate(SSH1_MSG_CHANNEL_CLOSE);
214 translate(SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION);
215 translate(SSH1_SMSG_X11_OPEN);
216 translate(SSH1_CMSG_PORT_FORWARD_REQUEST);
217 translate(SSH1_MSG_PORT_OPEN);
218 translate(SSH1_CMSG_AGENT_REQUEST_FORWARDING);
219 translate(SSH1_SMSG_AGENT_OPEN);
220 translate(SSH1_MSG_IGNORE);
221 translate(SSH1_CMSG_EXIT_CONFIRMATION);
222 translate(SSH1_CMSG_X11_REQUEST_FORWARDING);
223 translate(SSH1_CMSG_AUTH_RHOSTS_RSA);
224 translate(SSH1_MSG_DEBUG);
225 translate(SSH1_CMSG_REQUEST_COMPRESSION);
226 translate(SSH1_CMSG_AUTH_TIS);
227 translate(SSH1_SMSG_AUTH_TIS_CHALLENGE);
228 translate(SSH1_CMSG_AUTH_TIS_RESPONSE);
229 translate(SSH1_CMSG_AUTH_CCARD);
230 translate(SSH1_SMSG_AUTH_CCARD_CHALLENGE);
231 translate(SSH1_CMSG_AUTH_CCARD_RESPONSE);
232 return "unknown";
233}
234char *ssh2_pkt_type(int type)
235{
236 translate(SSH2_MSG_DISCONNECT);
237 translate(SSH2_MSG_IGNORE);
238 translate(SSH2_MSG_UNIMPLEMENTED);
239 translate(SSH2_MSG_DEBUG);
240 translate(SSH2_MSG_SERVICE_REQUEST);
241 translate(SSH2_MSG_SERVICE_ACCEPT);
242 translate(SSH2_MSG_KEXINIT);
243 translate(SSH2_MSG_NEWKEYS);
244 translatec(SSH2_MSG_KEXDH_INIT, SSH2_PKTCTX_DHGROUP1);
245 translatec(SSH2_MSG_KEXDH_REPLY, SSH2_PKTCTX_DHGROUP1);
246 translatec(SSH2_MSG_KEX_DH_GEX_REQUEST, SSH2_PKTCTX_DHGEX);
247 translatec(SSH2_MSG_KEX_DH_GEX_GROUP, SSH2_PKTCTX_DHGEX);
248 translatec(SSH2_MSG_KEX_DH_GEX_INIT, SSH2_PKTCTX_DHGEX);
249 translatec(SSH2_MSG_KEX_DH_GEX_REPLY, SSH2_PKTCTX_DHGEX);
250 translate(SSH2_MSG_USERAUTH_REQUEST);
251 translate(SSH2_MSG_USERAUTH_FAILURE);
252 translate(SSH2_MSG_USERAUTH_SUCCESS);
253 translate(SSH2_MSG_USERAUTH_BANNER);
254 translatec(SSH2_MSG_USERAUTH_PK_OK, SSH2_PKTCTX_PUBLICKEY);
255 translatec(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, SSH2_PKTCTX_PASSWORD);
256 translatec(SSH2_MSG_USERAUTH_INFO_REQUEST, SSH2_PKTCTX_KBDINTER);
257 translatec(SSH2_MSG_USERAUTH_INFO_RESPONSE, SSH2_PKTCTX_KBDINTER);
258 translate(SSH2_MSG_GLOBAL_REQUEST);
259 translate(SSH2_MSG_REQUEST_SUCCESS);
260 translate(SSH2_MSG_REQUEST_FAILURE);
261 translate(SSH2_MSG_CHANNEL_OPEN);
262 translate(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
263 translate(SSH2_MSG_CHANNEL_OPEN_FAILURE);
264 translate(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
265 translate(SSH2_MSG_CHANNEL_DATA);
266 translate(SSH2_MSG_CHANNEL_EXTENDED_DATA);
267 translate(SSH2_MSG_CHANNEL_EOF);
268 translate(SSH2_MSG_CHANNEL_CLOSE);
269 translate(SSH2_MSG_CHANNEL_REQUEST);
270 translate(SSH2_MSG_CHANNEL_SUCCESS);
271 translate(SSH2_MSG_CHANNEL_FAILURE);
272 return "unknown";
273}
274#undef translate
275#undef translatec
7d503c31 276
fb09bf1c 277#define GET_32BIT(cp) \
278 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
279 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
280 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
281 ((unsigned long)(unsigned char)(cp)[3]))
282
283#define PUT_32BIT(cp, value) { \
284 (cp)[0] = (unsigned char)((value) >> 24); \
285 (cp)[1] = (unsigned char)((value) >> 16); \
286 (cp)[2] = (unsigned char)((value) >> 8); \
287 (cp)[3] = (unsigned char)(value); }
288
7cca0d81 289enum { PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR, PKT_BIGNUM };
972a41c8 290
374330e2 291/* Coroutine mechanics for the sillier bits of the code */
292#define crBegin1 static int crLine = 0;
293#define crBegin2 switch(crLine) { case 0:;
294#define crBegin crBegin1; crBegin2;
295#define crFinish(z) } crLine = 0; return (z)
296#define crFinishV } crLine = 0; return
297#define crReturn(z) \
298 do {\
299 crLine=__LINE__; return (z); case __LINE__:;\
300 } while (0)
301#define crReturnV \
302 do {\
303 crLine=__LINE__; return; case __LINE__:;\
304 } while (0)
305#define crStop(z) do{ crLine = 0; return (z); }while(0)
306#define crStopV do{ crLine = 0; return; }while(0)
fb09bf1c 307#define crWaitUntil(c) do { crReturn(0); } while (!(c))
7cca0d81 308#define crWaitUntilV(c) do { crReturnV; } while (!(c))
374330e2 309
32874aea 310extern char *x11_init(Socket *, char *, void *);
311extern void x11_close(Socket);
5471d09a 312extern int x11_send(Socket, char *, int);
9c964e85 313extern void x11_invent_auth(char *, int, char *, int);
5471d09a 314extern void x11_unthrottle(Socket s);
315extern void x11_override_throttle(Socket s, int enable);
9c964e85 316
d74d141c 317extern char *pfd_newconnect(Socket * s, char *hostname, int port, void *c);
318extern char *pfd_addforward(char *desthost, int destport, int port);
319extern void pfd_close(Socket s);
5471d09a 320extern int pfd_send(Socket s, char *data, int len);
d74d141c 321extern void pfd_confirm(Socket s);
5471d09a 322extern void pfd_unthrottle(Socket s);
323extern void pfd_override_throttle(Socket s, int enable);
324
3d63ca2e 325static void ssh2_pkt_init(int pkt_type);
326static void ssh2_pkt_addbool(unsigned char value);
327static void ssh2_pkt_adduint32(unsigned long value);
328static void ssh2_pkt_addstring_start(void);
329static void ssh2_pkt_addstring_str(char *data);
330static void ssh2_pkt_addstring_data(char *data, int len);
331static void ssh2_pkt_addstring(char *data);
332static char *ssh2_mpint_fmt(Bignum b, int *len);
333static void ssh2_pkt_addmp(Bignum b);
334static int ssh2_pkt_construct(void);
335static void ssh2_pkt_send(void);
336
5471d09a 337/*
338 * Buffer management constants. There are several of these for
339 * various different purposes:
340 *
341 * - SSH1_BUFFER_LIMIT is the amount of backlog that must build up
342 * on a local data stream before we throttle the whole SSH
343 * connection (in SSH1 only). Throttling the whole connection is
344 * pretty drastic so we set this high in the hope it won't
345 * happen very often.
346 *
347 * - SSH_MAX_BACKLOG is the amount of backlog that must build up
348 * on the SSH connection itself before we defensively throttle
349 * _all_ local data streams. This is pretty drastic too (though
350 * thankfully unlikely in SSH2 since the window mechanism should
351 * ensure that the server never has any need to throttle its end
352 * of the connection), so we set this high as well.
353 *
354 * - OUR_V2_WINSIZE is the maximum window size we present on SSH2
355 * channels.
356 */
357
358#define SSH1_BUFFER_LIMIT 32768
359#define SSH_MAX_BACKLOG 32768
360#define OUR_V2_WINSIZE 16384
d74d141c 361
a92dd380 362const static struct ssh_kex *kex_algs[] = {
a92dd380 363 &ssh_diffiehellman_gex,
32874aea 364 &ssh_diffiehellman
365};
e5574168 366
85cc02bb 367const static struct ssh_signkey *hostkey_algs[] = { &ssh_rsa, &ssh_dss };
e5574168 368
32874aea 369static void nullmac_key(unsigned char *key)
370{
371}
372static void nullmac_generate(unsigned char *blk, int len,
373 unsigned long seq)
374{
375}
376static int nullmac_verify(unsigned char *blk, int len, unsigned long seq)
377{
378 return 1;
379}
57476f6b 380const static struct ssh_mac ssh_mac_none = {
d39f364a 381 nullmac_key, nullmac_key, 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
32874aea 390static void ssh_comp_none_init(void)
391{
392}
4ba9b64b 393static int ssh_comp_none_block(unsigned char *block, int len,
32874aea 394 unsigned char **outblock, int *outlen)
395{
396 return 0;
397}
398static int ssh_comp_none_disable(void)
399{
4ba9b64b 400 return 0;
401}
57476f6b 402const static struct ssh_compress ssh_comp_none = {
4ba9b64b 403 "none",
404 ssh_comp_none_init, ssh_comp_none_block,
63b00c83 405 ssh_comp_none_init, ssh_comp_none_block,
406 ssh_comp_none_disable
e5574168 407};
4ba9b64b 408extern const struct ssh_compress ssh_zlib;
409const static struct ssh_compress *compressions[] = {
32874aea 410 &ssh_zlib, &ssh_comp_none
411};
374330e2 412
32874aea 413enum { /* channel types */
783415f8 414 CHAN_MAINSESSION,
415 CHAN_X11,
416 CHAN_AGENT,
bc240b21 417 CHAN_SOCKDATA,
418 CHAN_SOCKDATA_DORMANT /* one the remote hasn't confirmed */
783415f8 419};
420
dacbd0e8 421/*
422 * 2-3-4 tree storing channels.
423 */
424struct ssh_channel {
d211621f 425 unsigned remoteid, localid;
dacbd0e8 426 int type;
427 int closes;
5471d09a 428 union {
429 struct ssh1_data_channel {
430 int throttling;
431 } v1;
432 struct ssh2_data_channel {
433 bufchain outbuffer;
434 unsigned remwindow, remmaxpkt;
435 unsigned locwindow;
436 } v2;
437 } v;
dacbd0e8 438 union {
32874aea 439 struct ssh_agent_channel {
440 unsigned char *message;
441 unsigned char msglen[4];
442 int lensofar, totallen;
443 } a;
444 struct ssh_x11_channel {
445 Socket s;
446 } x11;
d74d141c 447 struct ssh_pfd_channel {
448 Socket s;
449 } pfd;
dacbd0e8 450 } u;
451};
57476f6b 452
d74d141c 453/*
bc240b21 454 * 2-3-4 tree storing remote->local port forwardings. SSH 1 and SSH
455 * 2 use this structure in different ways, reflecting SSH 2's
456 * altogether saner approach to port forwarding.
457 *
458 * In SSH 1, you arrange a remote forwarding by sending the server
459 * the remote port number, and the local destination host:port.
460 * When a connection comes in, the server sends you back that
461 * host:port pair, and you connect to it. This is a ready-made
462 * security hole if you're not on the ball: a malicious server
463 * could send you back _any_ host:port pair, so if you trustingly
464 * connect to the address it gives you then you've just opened the
465 * entire inside of your corporate network just by connecting
466 * through it to a dodgy SSH server. Hence, we must store a list of
467 * host:port pairs we _are_ trying to forward to, and reject a
468 * connection request from the server if it's not in the list.
469 *
470 * In SSH 2, each side of the connection minds its own business and
471 * doesn't send unnecessary information to the other. You arrange a
472 * remote forwarding by sending the server just the remote port
473 * number. When a connection comes in, the server tells you which
474 * of its ports was connected to; and _you_ have to remember what
475 * local host:port pair went with that port number.
476 *
477 * Hence: in SSH 1 this structure stores host:port pairs we intend
478 * to allow connections to, and is indexed by those host:port
479 * pairs. In SSH 2 it stores a mapping from source port to
480 * destination host:port pair, and is indexed by source port.
d74d141c 481 */
482struct ssh_rportfwd {
bc240b21 483 unsigned sport, dport;
484 char dhost[256];
d74d141c 485};
486
57476f6b 487struct Packet {
488 long length;
489 int type;
490 unsigned char *data;
491 unsigned char *body;
492 long savedpos;
493 long maxlen;
494};
495
0db56f73 496static SHA_State exhash, exhashbase;
57476f6b 497
8df7a775 498static Socket s = NULL;
57476f6b 499
500static unsigned char session_key[32];
4ba9b64b 501static int ssh1_compressing;
b96dc54c 502static int ssh1_remote_protoflags;
503static int ssh1_local_protoflags;
db7d555c 504static int ssh_agentfwd_enabled;
9c964e85 505static int ssh_X11_fwd_enabled;
7d503c31 506static int ssh_remote_bugs;
57476f6b 507static const struct ssh_cipher *cipher = NULL;
0a3f1d48 508static const struct ssh2_cipher *cscipher = NULL;
509static const struct ssh2_cipher *sccipher = NULL;
57476f6b 510static const struct ssh_mac *csmac = NULL;
511static const struct ssh_mac *scmac = NULL;
512static const struct ssh_compress *cscomp = NULL;
513static const struct ssh_compress *sccomp = NULL;
514static const struct ssh_kex *kex = NULL;
e055a386 515static const struct ssh_signkey *hostkey = NULL;
65a22376 516static unsigned char ssh2_session_id[20];
32874aea 517int (*ssh_get_line) (const char *prompt, char *str, int maxlen,
518 int is_pw) = NULL;
57476f6b 519
520static char *savedhost;
521static int savedport;
522static int ssh_send_ok;
0965bee0 523static int ssh_echoing, ssh_editing;
57476f6b 524
32874aea 525static tree234 *ssh_channels; /* indexed by local id */
57476f6b 526static struct ssh_channel *mainchan; /* primary session channel */
d8d6c7e5 527static int ssh_exitcode = -1;
57476f6b 528
d74d141c 529static tree234 *ssh_rportfwds;
530
57476f6b 531static enum {
3687d221 532 SSH_STATE_PREPACKET,
57476f6b 533 SSH_STATE_BEFORE_SIZE,
534 SSH_STATE_INTERMED,
535 SSH_STATE_SESSION,
536 SSH_STATE_CLOSED
3687d221 537} ssh_state = SSH_STATE_PREPACKET;
57476f6b 538
3687d221 539static int size_needed = FALSE, eof_needed = FALSE;
57476f6b 540
541static struct Packet pktin = { 0, 0, NULL, NULL, 0 };
542static struct Packet pktout = { 0, 0, NULL, NULL, 0 };
b185170a 543static unsigned char *deferred_send_data = NULL;
544static int deferred_len = 0, deferred_size = 0;
57476f6b 545
fd5e5847 546/*
547 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
548 * that fails. This variable is the means by which scp.c can reach
549 * into the SSH code and find out which one it got.
550 */
551int ssh_fallback_cmd = 0;
552
57476f6b 553static int ssh_version;
5471d09a 554static int ssh1_throttle_count;
555static int ssh_overall_bufsize;
556static int ssh_throttled_all;
557static int ssh1_stdout_throttling;
32874aea 558static void (*ssh_protocol) (unsigned char *in, int inlen, int ispkt);
57476f6b 559static void ssh1_protocol(unsigned char *in, int inlen, int ispkt);
560static void ssh2_protocol(unsigned char *in, int inlen, int ispkt);
561static void ssh_size(void);
32874aea 562static void ssh_special(Telnet_Special);
5471d09a 563static int ssh2_try_send(struct ssh_channel *c);
32874aea 564static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
565 int len);
5471d09a 566static void ssh_throttle_all(int enable, int bufsize);
567static void ssh2_set_window(struct ssh_channel *c, unsigned newwin);
32874aea 568static int (*s_rdpkt) (unsigned char **data, int *datalen);
5471d09a 569static int ssh_sendbuffer(void);
57476f6b 570
571static struct rdpkt1_state_tag {
572 long len, pad, biglen, to_read;
573 unsigned long realcrc, gotcrc;
574 unsigned char *p;
575 int i;
576 int chunk;
577} rdpkt1_state;
578
960e736a 579static struct rdpkt2_state_tag {
580 long len, pad, payload, packetlen, maclen;
581 int i;
582 int cipherblk;
583 unsigned long incoming_sequence;
584} rdpkt2_state;
585
32874aea 586static int ssh_channelcmp(void *av, void *bv)
587{
588 struct ssh_channel *a = (struct ssh_channel *) av;
589 struct ssh_channel *b = (struct ssh_channel *) bv;
590 if (a->localid < b->localid)
591 return -1;
592 if (a->localid > b->localid)
593 return +1;
dacbd0e8 594 return 0;
595}
32874aea 596static int ssh_channelfind(void *av, void *bv)
597{
598 unsigned *a = (unsigned *) av;
599 struct ssh_channel *b = (struct ssh_channel *) bv;
600 if (*a < b->localid)
601 return -1;
602 if (*a > b->localid)
603 return +1;
dacbd0e8 604 return 0;
605}
606
bc240b21 607static int ssh_rportcmp_ssh1(void *av, void *bv)
d74d141c 608{
609 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
610 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
611 int i;
bc240b21 612 if ( (i = strcmp(a->dhost, b->dhost)) != 0)
d74d141c 613 return i < 0 ? -1 : +1;
bc240b21 614 if (a->dport > b->dport)
615 return +1;
616 if (a->dport < b->dport)
617 return -1;
618 return 0;
619}
620
621static int ssh_rportcmp_ssh2(void *av, void *bv)
622{
623 struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
624 struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
cdcbdf3b 625
bc240b21 626 if (a->sport > b->sport)
d74d141c 627 return +1;
bc240b21 628 if (a->sport < b->sport)
629 return -1;
d74d141c 630 return 0;
631}
632
32874aea 633static int alloc_channel_id(void)
634{
260f3dec 635 const unsigned CHANNEL_NUMBER_OFFSET = 256;
636 unsigned low, high, mid;
d2371c81 637 int tsize;
638 struct ssh_channel *c;
639
640 /*
641 * First-fit allocation of channel numbers: always pick the
642 * lowest unused one. To do this, binary-search using the
643 * counted B-tree to find the largest channel ID which is in a
644 * contiguous sequence from the beginning. (Precisely
645 * everything in that sequence must have ID equal to its tree
646 * index plus CHANNEL_NUMBER_OFFSET.)
647 */
648 tsize = count234(ssh_channels);
649
32874aea 650 low = -1;
651 high = tsize;
d2371c81 652 while (high - low > 1) {
653 mid = (high + low) / 2;
654 c = index234(ssh_channels, mid);
655 if (c->localid == mid + CHANNEL_NUMBER_OFFSET)
656 low = mid; /* this one is fine */
657 else
658 high = mid; /* this one is past it */
659 }
660 /*
661 * Now low points to either -1, or the tree index of the
662 * largest ID in the initial sequence.
663 */
664 {
665 unsigned i = low + 1 + CHANNEL_NUMBER_OFFSET;
666 assert(NULL == find234(ssh_channels, &i, ssh_channelfind));
667 }
668 return low + 1 + CHANNEL_NUMBER_OFFSET;
669}
670
32874aea 671static void c_write(char *buf, int len)
672{
67779be7 673 if ((flags & FLAG_STDERR)) {
32874aea 674 int i;
675 for (i = 0; i < len; i++)
676 if (buf[i] != '\r')
677 fputc(buf[i], stderr);
fb09bf1c 678 return;
679 }
fe50e814 680 from_backend(1, buf, len);
3bdaf79d 681}
682
32874aea 683static void c_write_untrusted(char *buf, int len)
684{
a209e957 685 int i;
686 for (i = 0; i < len; i++) {
32874aea 687 if (buf[i] == '\n')
688 c_write("\r\n", 2);
689 else if ((buf[i] & 0x60) || (buf[i] == '\r'))
690 c_write(buf + i, 1);
a209e957 691 }
692}
693
32874aea 694static void c_write_str(char *buf)
695{
1408a877 696 c_write(buf, strlen(buf));
697}
698
fb09bf1c 699/*
700 * Collect incoming data in the incoming packet buffer.
e5574168 701 * Decipher and verify the packet when it is completely read.
702 * Drop SSH1_MSG_DEBUG and SSH1_MSG_IGNORE packets.
fb09bf1c 703 * Update the *data and *datalen variables.
704 * Return the additional nr of bytes needed, or 0 when
705 * a complete packet is available.
706 */
e5574168 707static int ssh1_rdpkt(unsigned char **data, int *datalen)
fb09bf1c 708{
57476f6b 709 struct rdpkt1_state_tag *st = &rdpkt1_state;
374330e2 710
711 crBegin;
374330e2 712
32874aea 713 next_packet:
37508af4 714
fb09bf1c 715 pktin.type = 0;
716 pktin.length = 0;
374330e2 717
57476f6b 718 for (st->i = st->len = 0; st->i < 4; st->i++) {
fb09bf1c 719 while ((*datalen) == 0)
32874aea 720 crReturn(4 - st->i);
57476f6b 721 st->len = (st->len << 8) + **data;
fb09bf1c 722 (*data)++, (*datalen)--;
723 }
374330e2 724
57476f6b 725 st->pad = 8 - (st->len % 8);
726 st->biglen = st->len + st->pad;
727 pktin.length = st->len - 5;
fb09bf1c 728
57476f6b 729 if (pktin.maxlen < st->biglen) {
730 pktin.maxlen = st->biglen;
32874aea 731 pktin.data = (pktin.data == NULL ? smalloc(st->biglen + APIEXTRA) :
732 srealloc(pktin.data, st->biglen + APIEXTRA));
fb09bf1c 733 if (!pktin.data)
734 fatalbox("Out of memory");
735 }
374330e2 736
57476f6b 737 st->to_read = st->biglen;
738 st->p = pktin.data;
739 while (st->to_read > 0) {
32874aea 740 st->chunk = st->to_read;
fb09bf1c 741 while ((*datalen) == 0)
57476f6b 742 crReturn(st->to_read);
743 if (st->chunk > (*datalen))
744 st->chunk = (*datalen);
745 memcpy(st->p, *data, st->chunk);
746 *data += st->chunk;
747 *datalen -= st->chunk;
748 st->p += st->chunk;
749 st->to_read -= st->chunk;
fb09bf1c 750 }
374330e2 751
9a3a93a5 752 if (cipher && detect_attack(pktin.data, st->biglen, NULL)) {
753 bombout(("Network attack (CRC compensation) detected!"));
754 crReturn(0);
755 }
756
fb09bf1c 757 if (cipher)
57476f6b 758 cipher->decrypt(pktin.data, st->biglen);
374330e2 759
32874aea 760 st->realcrc = crc32(pktin.data, st->biglen - 4);
761 st->gotcrc = GET_32BIT(pktin.data + st->biglen - 4);
57476f6b 762 if (st->gotcrc != st->realcrc) {
8d5de777 763 bombout(("Incorrect CRC received on packet"));
32874aea 764 crReturn(0);
fb09bf1c 765 }
572f871e 766
4ba9b64b 767 pktin.body = pktin.data + st->pad + 1;
768
769 if (ssh1_compressing) {
770 unsigned char *decompblk;
771 int decomplen;
32874aea 772 zlib_decompress_block(pktin.body - 1, pktin.length + 1,
4ba9b64b 773 &decompblk, &decomplen);
774
775 if (pktin.maxlen < st->pad + decomplen) {
776 pktin.maxlen = st->pad + decomplen;
32874aea 777 pktin.data = srealloc(pktin.data, pktin.maxlen + APIEXTRA);
778 pktin.body = pktin.data + st->pad + 1;
4ba9b64b 779 if (!pktin.data)
780 fatalbox("Out of memory");
781 }
782
32874aea 783 memcpy(pktin.body - 1, decompblk, decomplen);
dcbde236 784 sfree(decompblk);
32874aea 785 pktin.length = decomplen - 1;
4ba9b64b 786 }
787
00db133f 788 pktin.type = pktin.body[-1];
789
790 log_packet(PKT_INCOMING, pktin.type, ssh1_pkt_type(pktin.type),
791 pktin.body, pktin.length);
792
e5574168 793 if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
32874aea 794 pktin.type == SSH1_SMSG_STDERR_DATA ||
795 pktin.type == SSH1_MSG_DEBUG ||
796 pktin.type == SSH1_SMSG_AUTH_TIS_CHALLENGE ||
797 pktin.type == SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
3d63ca2e 798 long stringlen = GET_32BIT(pktin.body);
799 if (stringlen + 4 != pktin.length) {
8d5de777 800 bombout(("Received data packet with bogus string length"));
32874aea 801 crReturn(0);
802 }
fb09bf1c 803 }
804
e5574168 805 if (pktin.type == SSH1_MSG_DEBUG) {
fb09bf1c 806 /* log debug message */
807 char buf[80];
3d63ca2e 808 int stringlen = GET_32BIT(pktin.body);
fb09bf1c 809 strcpy(buf, "Remote: ");
3d63ca2e 810 if (stringlen > 70)
811 stringlen = 70;
812 memcpy(buf + 8, pktin.body + 4, stringlen);
813 buf[8 + stringlen] = '\0';
fb09bf1c 814 logevent(buf);
815 goto next_packet;
e5574168 816 } else if (pktin.type == SSH1_MSG_IGNORE) {
fb09bf1c 817 /* do nothing */
818 goto next_packet;
819 }
820
38c4a8da 821 if (pktin.type == SSH1_MSG_DISCONNECT) {
822 /* log reason code in disconnect message */
823 char buf[256];
260f3dec 824 unsigned msglen = GET_32BIT(pktin.body);
825 unsigned nowlen;
38c4a8da 826 strcpy(buf, "Remote sent disconnect: ");
827 nowlen = strlen(buf);
32874aea 828 if (msglen > sizeof(buf) - nowlen - 1)
829 msglen = sizeof(buf) - nowlen - 1;
830 memcpy(buf + nowlen, pktin.body + 4, msglen);
831 buf[nowlen + msglen] = '\0';
247308b5 832 /* logevent(buf); (this is now done within the bombout macro) */
4eb195cc 833 bombout(("Server sent disconnect message:\n\"%s\"", buf+nowlen));
e14d0f19 834 crReturn(0);
38c4a8da 835 }
836
fb09bf1c 837 crFinish(0);
838}
839
e5574168 840static int ssh2_rdpkt(unsigned char **data, int *datalen)
841{
960e736a 842 struct rdpkt2_state_tag *st = &rdpkt2_state;
e5574168 843
844 crBegin;
845
32874aea 846 next_packet:
e5574168 847 pktin.type = 0;
848 pktin.length = 0;
960e736a 849 if (sccipher)
32874aea 850 st->cipherblk = sccipher->blksize;
e5574168 851 else
32874aea 852 st->cipherblk = 8;
960e736a 853 if (st->cipherblk < 8)
32874aea 854 st->cipherblk = 8;
960e736a 855
856 if (pktin.maxlen < st->cipherblk) {
857 pktin.maxlen = st->cipherblk;
32874aea 858 pktin.data =
859 (pktin.data ==
860 NULL ? smalloc(st->cipherblk +
861 APIEXTRA) : srealloc(pktin.data,
862 st->cipherblk +
863 APIEXTRA));
e5574168 864 if (!pktin.data)
865 fatalbox("Out of memory");
866 }
867
868 /*
869 * Acquire and decrypt the first block of the packet. This will
870 * contain the length and padding details.
871 */
32874aea 872 for (st->i = st->len = 0; st->i < st->cipherblk; st->i++) {
e5574168 873 while ((*datalen) == 0)
32874aea 874 crReturn(st->cipherblk - st->i);
960e736a 875 pktin.data[st->i] = *(*data)++;
32874aea 876 (*datalen)--;
e5574168 877 }
4252c9cc 878
e5574168 879 if (sccipher)
32874aea 880 sccipher->decrypt(pktin.data, st->cipherblk);
e5574168 881
882 /*
883 * Now get the length and padding figures.
884 */
960e736a 885 st->len = GET_32BIT(pktin.data);
886 st->pad = pktin.data[4];
e5574168 887
888 /*
889 * This enables us to deduce the payload length.
890 */
960e736a 891 st->payload = st->len - st->pad - 1;
e5574168 892
960e736a 893 pktin.length = st->payload + 5;
e5574168 894
895 /*
896 * So now we can work out the total packet length.
897 */
960e736a 898 st->packetlen = st->len + 4;
899 st->maclen = scmac ? scmac->len : 0;
e5574168 900
901 /*
902 * Adjust memory allocation if packet is too big.
903 */
32874aea 904 if (pktin.maxlen < st->packetlen + st->maclen) {
905 pktin.maxlen = st->packetlen + st->maclen;
906 pktin.data =
907 (pktin.data ==
908 NULL ? smalloc(pktin.maxlen + APIEXTRA) : srealloc(pktin.data,
909 pktin.maxlen
910 +
911 APIEXTRA));
e5574168 912 if (!pktin.data)
913 fatalbox("Out of memory");
914 }
915
916 /*
917 * Read and decrypt the remainder of the packet.
918 */
32874aea 919 for (st->i = st->cipherblk; st->i < st->packetlen + st->maclen;
920 st->i++) {
e5574168 921 while ((*datalen) == 0)
960e736a 922 crReturn(st->packetlen + st->maclen - st->i);
923 pktin.data[st->i] = *(*data)++;
32874aea 924 (*datalen)--;
e5574168 925 }
926 /* Decrypt everything _except_ the MAC. */
927 if (sccipher)
32874aea 928 sccipher->decrypt(pktin.data + st->cipherblk,
929 st->packetlen - st->cipherblk);
e5574168 930
931 /*
932 * Check the MAC.
933 */
32874aea 934 if (scmac
935 && !scmac->verify(pktin.data, st->len + 4,
936 st->incoming_sequence)) {
8d5de777 937 bombout(("Incorrect MAC received on packet"));
32874aea 938 crReturn(0);
8d5de777 939 }
32874aea 940 st->incoming_sequence++; /* whether or not we MACed */
e5574168 941
4ba9b64b 942 /*
943 * Decompress packet payload.
944 */
945 {
946 unsigned char *newpayload;
947 int newlen;
32874aea 948 if (sccomp && sccomp->decompress(pktin.data + 5, pktin.length - 5,
4ba9b64b 949 &newpayload, &newlen)) {
32874aea 950 if (pktin.maxlen < newlen + 5) {
951 pktin.maxlen = newlen + 5;
952 pktin.data =
953 (pktin.data ==
954 NULL ? smalloc(pktin.maxlen +
955 APIEXTRA) : srealloc(pktin.data,
956 pktin.maxlen +
957 APIEXTRA));
4ba9b64b 958 if (!pktin.data)
959 fatalbox("Out of memory");
960 }
961 pktin.length = 5 + newlen;
32874aea 962 memcpy(pktin.data + 5, newpayload, newlen);
dcbde236 963 sfree(newpayload);
4ba9b64b 964 }
965 }
966
e5574168 967 pktin.savedpos = 6;
968 pktin.type = pktin.data[5];
e5574168 969
00db133f 970 log_packet(PKT_INCOMING, pktin.type, ssh2_pkt_type(pktin.type),
971 pktin.data+6, pktin.length-6);
972
3d63ca2e 973 switch (pktin.type) {
974 /*
975 * These packets we must handle instantly.
976 */
977 case SSH2_MSG_DISCONNECT:
978 {
979 /* log reason code in disconnect message */
980 char buf[256];
981 int reason = GET_32BIT(pktin.data + 6);
982 unsigned msglen = GET_32BIT(pktin.data + 10);
983 unsigned nowlen;
984 if (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) {
985 sprintf(buf, "Received disconnect message (%s)",
986 ssh2_disconnect_reasons[reason]);
987 } else {
988 sprintf(buf, "Received disconnect message (unknown type %d)",
989 reason);
990 }
991 logevent(buf);
992 strcpy(buf, "Disconnection message text: ");
993 nowlen = strlen(buf);
994 if (msglen > sizeof(buf) - nowlen - 1)
995 msglen = sizeof(buf) - nowlen - 1;
996 memcpy(buf + nowlen, pktin.data + 14, msglen);
997 buf[nowlen + msglen] = '\0';
998 logevent(buf);
999 bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
1000 reason,
1001 (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) ?
1002 ssh2_disconnect_reasons[reason] : "unknown",
1003 buf+nowlen));
1004 crReturn(0);
1005 }
1006 break;
1007 case SSH2_MSG_IGNORE:
1008 goto next_packet;
1009 case SSH2_MSG_DEBUG:
1010 {
1011 /* log the debug message */
1012 char buf[512];
1013 /* int display = pktin.body[6]; */
1014 int stringlen = GET_32BIT(pktin.data+7);
1015 int prefix;
1016 strcpy(buf, "Remote debug message: ");
1017 prefix = strlen(buf);
1018 if (stringlen > sizeof(buf)-prefix-1)
1019 stringlen = sizeof(buf)-prefix-1;
1020 memcpy(buf + prefix, pktin.data + 11, stringlen);
1021 buf[prefix + stringlen] = '\0';
1022 logevent(buf);
38c4a8da 1023 }
3d63ca2e 1024 goto next_packet; /* FIXME: print the debug message */
1025
1026 /*
1027 * These packets we need do nothing about here.
1028 */
1029 case SSH2_MSG_UNIMPLEMENTED:
1030 case SSH2_MSG_SERVICE_REQUEST:
1031 case SSH2_MSG_SERVICE_ACCEPT:
1032 case SSH2_MSG_KEXINIT:
1033 case SSH2_MSG_NEWKEYS:
1034 case SSH2_MSG_KEXDH_INIT:
1035 case SSH2_MSG_KEXDH_REPLY:
1036 /* case SSH2_MSG_KEX_DH_GEX_REQUEST: duplicate case value */
1037 /* case SSH2_MSG_KEX_DH_GEX_GROUP: duplicate case value */
1038 case SSH2_MSG_KEX_DH_GEX_INIT:
1039 case SSH2_MSG_KEX_DH_GEX_REPLY:
1040 case SSH2_MSG_USERAUTH_REQUEST:
1041 case SSH2_MSG_USERAUTH_FAILURE:
1042 case SSH2_MSG_USERAUTH_SUCCESS:
1043 case SSH2_MSG_USERAUTH_BANNER:
1044 case SSH2_MSG_USERAUTH_PK_OK:
1045 /* case SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: duplicate case value */
1046 /* case SSH2_MSG_USERAUTH_INFO_REQUEST: duplicate case value */
1047 case SSH2_MSG_USERAUTH_INFO_RESPONSE:
1048 case SSH2_MSG_GLOBAL_REQUEST:
1049 case SSH2_MSG_REQUEST_SUCCESS:
1050 case SSH2_MSG_REQUEST_FAILURE:
1051 case SSH2_MSG_CHANNEL_OPEN:
1052 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
1053 case SSH2_MSG_CHANNEL_OPEN_FAILURE:
1054 case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
1055 case SSH2_MSG_CHANNEL_DATA:
1056 case SSH2_MSG_CHANNEL_EXTENDED_DATA:
1057 case SSH2_MSG_CHANNEL_EOF:
1058 case SSH2_MSG_CHANNEL_CLOSE:
1059 case SSH2_MSG_CHANNEL_REQUEST:
1060 case SSH2_MSG_CHANNEL_SUCCESS:
1061 case SSH2_MSG_CHANNEL_FAILURE:
1062 break;
1063
1064 /*
1065 * For anything else we send SSH2_MSG_UNIMPLEMENTED.
1066 */
1067 default:
1068 ssh2_pkt_init(SSH2_MSG_UNIMPLEMENTED);
1069 ssh2_pkt_adduint32(st->incoming_sequence - 1);
1070 ssh2_pkt_send();
1071 break;
38c4a8da 1072 }
1073
e5574168 1074 crFinish(0);
1075}
1076
32874aea 1077static void ssh1_pktout_size(int len)
1078{
374330e2 1079 int pad, biglen;
1080
1081 len += 5; /* type and CRC */
32874aea 1082 pad = 8 - (len % 8);
374330e2 1083 biglen = len + pad;
1084
32874aea 1085 pktout.length = len - 5;
374330e2 1086 if (pktout.maxlen < biglen) {
1087 pktout.maxlen = biglen;
8f203108 1088#ifdef MSCRYPTOAPI
fb09bf1c 1089 /* Allocate enough buffer space for extra block
8f203108 1090 * for MS CryptEncrypt() */
32874aea 1091 pktout.data = (pktout.data == NULL ? smalloc(biglen + 12) :
1092 srealloc(pktout.data, biglen + 12));
8f203108 1093#else
32874aea 1094 pktout.data = (pktout.data == NULL ? smalloc(biglen + 4) :
1095 srealloc(pktout.data, biglen + 4));
8f203108 1096#endif
374330e2 1097 if (!pktout.data)
1098 fatalbox("Out of memory");
1099 }
32874aea 1100 pktout.body = pktout.data + 4 + pad + 1;
4ba9b64b 1101}
374330e2 1102
32874aea 1103static void s_wrpkt_start(int type, int len)
1104{
4ba9b64b 1105 ssh1_pktout_size(len);
374330e2 1106 pktout.type = type;
374330e2 1107}
1108
32874aea 1109static int s_wrpkt_prepare(void)
1110{
374330e2 1111 int pad, len, biglen, i;
1112 unsigned long crc;
1113
4ba9b64b 1114 pktout.body[-1] = pktout.type;
1115
00db133f 1116 log_packet(PKT_OUTGOING, pktout.type, ssh1_pkt_type(pktout.type),
1117 pktout.body, pktout.length);
1118
4ba9b64b 1119 if (ssh1_compressing) {
1120 unsigned char *compblk;
1121 int complen;
32874aea 1122 zlib_compress_block(pktout.body - 1, pktout.length + 1,
4ba9b64b 1123 &compblk, &complen);
32874aea 1124 ssh1_pktout_size(complen - 1);
1125 memcpy(pktout.body - 1, compblk, complen);
dcbde236 1126 sfree(compblk);
4ba9b64b 1127 }
1128
374330e2 1129 len = pktout.length + 5; /* type and CRC */
32874aea 1130 pad = 8 - (len % 8);
374330e2 1131 biglen = len + pad;
1132
32874aea 1133 for (i = 0; i < pad; i++)
1134 pktout.data[i + 4] = random_byte();
1135 crc = crc32(pktout.data + 4, biglen - 4);
1136 PUT_32BIT(pktout.data + biglen, crc);
fb09bf1c 1137 PUT_32BIT(pktout.data, len);
374330e2 1138
1139 if (cipher)
32874aea 1140 cipher->encrypt(pktout.data + 4, biglen);
374330e2 1141
32874aea 1142 return biglen + 4;
39065bed 1143}
1144
32874aea 1145static void s_wrpkt(void)
1146{
5471d09a 1147 int len, backlog;
39065bed 1148 len = s_wrpkt_prepare();
5471d09a 1149 backlog = sk_write(s, pktout.data, len);
1150 if (backlog > SSH_MAX_BACKLOG)
1151 ssh_throttle_all(1, backlog);
39065bed 1152}
1153
32874aea 1154static void s_wrpkt_defer(void)
1155{
39065bed 1156 int len;
1157 len = s_wrpkt_prepare();
1158 if (deferred_len + len > deferred_size) {
32874aea 1159 deferred_size = deferred_len + len + 128;
1160 deferred_send_data = srealloc(deferred_send_data, deferred_size);
39065bed 1161 }
32874aea 1162 memcpy(deferred_send_data + deferred_len, pktout.data, len);
39065bed 1163 deferred_len += len;
374330e2 1164}
1165
fb09bf1c 1166/*
39065bed 1167 * Construct a packet with the specified contents.
fb09bf1c 1168 */
39065bed 1169static void construct_packet(int pkttype, va_list ap1, va_list ap2)
fb09bf1c 1170{
fb09bf1c 1171 unsigned char *p, *argp, argchar;
1172 unsigned long argint;
1173 int pktlen, argtype, arglen;
7cca0d81 1174 Bignum bn;
fb09bf1c 1175
1176 pktlen = 0;
39065bed 1177 while ((argtype = va_arg(ap1, int)) != PKT_END) {
fb09bf1c 1178 switch (argtype) {
1179 case PKT_INT:
39065bed 1180 (void) va_arg(ap1, int);
fb09bf1c 1181 pktlen += 4;
1182 break;
1183 case PKT_CHAR:
39065bed 1184 (void) va_arg(ap1, char);
fb09bf1c 1185 pktlen++;
1186 break;
1187 case PKT_DATA:
39065bed 1188 (void) va_arg(ap1, unsigned char *);
1189 arglen = va_arg(ap1, int);
fb09bf1c 1190 pktlen += arglen;
1191 break;
1192 case PKT_STR:
39065bed 1193 argp = va_arg(ap1, unsigned char *);
fb09bf1c 1194 arglen = strlen(argp);
1195 pktlen += 4 + arglen;
1196 break;
7cca0d81 1197 case PKT_BIGNUM:
39065bed 1198 bn = va_arg(ap1, Bignum);
32874aea 1199 pktlen += ssh1_bignum_length(bn);
7cca0d81 1200 break;
fb09bf1c 1201 default:
1202 assert(0);
1203 }
1204 }
fb09bf1c 1205
1206 s_wrpkt_start(pkttype, pktlen);
1207 p = pktout.body;
1208
39065bed 1209 while ((argtype = va_arg(ap2, int)) != PKT_END) {
fb09bf1c 1210 switch (argtype) {
1211 case PKT_INT:
39065bed 1212 argint = va_arg(ap2, int);
fb09bf1c 1213 PUT_32BIT(p, argint);
1214 p += 4;
1215 break;
1216 case PKT_CHAR:
39065bed 1217 argchar = va_arg(ap2, unsigned char);
fb09bf1c 1218 *p = argchar;
1219 p++;
1220 break;
1221 case PKT_DATA:
39065bed 1222 argp = va_arg(ap2, unsigned char *);
1223 arglen = va_arg(ap2, int);
fb09bf1c 1224 memcpy(p, argp, arglen);
1225 p += arglen;
1226 break;
1227 case PKT_STR:
39065bed 1228 argp = va_arg(ap2, unsigned char *);
fb09bf1c 1229 arglen = strlen(argp);
1230 PUT_32BIT(p, arglen);
1231 memcpy(p + 4, argp, arglen);
1232 p += 4 + arglen;
1233 break;
7cca0d81 1234 case PKT_BIGNUM:
39065bed 1235 bn = va_arg(ap2, Bignum);
32874aea 1236 p += ssh1_write_bignum(p, bn);
7cca0d81 1237 break;
fb09bf1c 1238 }
1239 }
39065bed 1240}
fb09bf1c 1241
32874aea 1242static void send_packet(int pkttype, ...)
1243{
39065bed 1244 va_list ap1, ap2;
1245 va_start(ap1, pkttype);
1246 va_start(ap2, pkttype);
1247 construct_packet(pkttype, ap1, ap2);
fb09bf1c 1248 s_wrpkt();
1249}
1250
32874aea 1251static void defer_packet(int pkttype, ...)
1252{
39065bed 1253 va_list ap1, ap2;
1254 va_start(ap1, pkttype);
1255 va_start(ap2, pkttype);
1256 construct_packet(pkttype, ap1, ap2);
1257 s_wrpkt_defer();
1258}
1259
32874aea 1260static int ssh_versioncmp(char *a, char *b)
1261{
9697bfd2 1262 char *ae, *be;
1263 unsigned long av, bv;
1264
43aa02a7 1265 av = strtoul(a, &ae, 10);
1266 bv = strtoul(b, &be, 10);
32874aea 1267 if (av != bv)
1268 return (av < bv ? -1 : +1);
1269 if (*ae == '.')
1270 ae++;
1271 if (*be == '.')
1272 be++;
43aa02a7 1273 av = strtoul(ae, &ae, 10);
1274 bv = strtoul(be, &be, 10);
32874aea 1275 if (av != bv)
1276 return (av < bv ? -1 : +1);
9697bfd2 1277 return 0;
1278}
1279
e5574168 1280
1281/*
a92dd380 1282 * Utility routines for putting an SSH-protocol `string' and
1283 * `uint32' into a SHA state.
e5574168 1284 */
1285#include <stdio.h>
32874aea 1286static void sha_string(SHA_State * s, void *str, int len)
1287{
e5574168 1288 unsigned char lenblk[4];
e5574168 1289 PUT_32BIT(lenblk, len);
e5574168 1290 SHA_Bytes(s, lenblk, 4);
e5574168 1291 SHA_Bytes(s, str, len);
1292}
1293
32874aea 1294static void sha_uint32(SHA_State * s, unsigned i)
1295{
a92dd380 1296 unsigned char intblk[4];
1297 PUT_32BIT(intblk, i);
1298 SHA_Bytes(s, intblk, 4);
1299}
1300
7cca0d81 1301/*
1302 * SSH2 packet construction functions.
1303 */
32874aea 1304static void ssh2_pkt_ensure(int length)
1305{
783415f8 1306 if (pktout.maxlen < length) {
32874aea 1307 pktout.maxlen = length + 256;
1308 pktout.data =
1309 (pktout.data ==
1310 NULL ? smalloc(pktout.maxlen +
1311 APIEXTRA) : srealloc(pktout.data,
1312 pktout.maxlen +
1313 APIEXTRA));
1314 if (!pktout.data)
1315 fatalbox("Out of memory");
7cca0d81 1316 }
783415f8 1317}
32874aea 1318static void ssh2_pkt_adddata(void *data, int len)
1319{
783415f8 1320 pktout.length += len;
1321 ssh2_pkt_ensure(pktout.length);
32874aea 1322 memcpy(pktout.data + pktout.length - len, data, len);
7cca0d81 1323}
32874aea 1324static void ssh2_pkt_addbyte(unsigned char byte)
1325{
7cca0d81 1326 ssh2_pkt_adddata(&byte, 1);
1327}
32874aea 1328static void ssh2_pkt_init(int pkt_type)
1329{
7cca0d81 1330 pktout.length = 5;
32874aea 1331 ssh2_pkt_addbyte((unsigned char) pkt_type);
7cca0d81 1332}
32874aea 1333static void ssh2_pkt_addbool(unsigned char value)
1334{
7cca0d81 1335 ssh2_pkt_adddata(&value, 1);
1336}
32874aea 1337static void ssh2_pkt_adduint32(unsigned long value)
1338{
7cca0d81 1339 unsigned char x[4];
1340 PUT_32BIT(x, value);
1341 ssh2_pkt_adddata(x, 4);
1342}
32874aea 1343static void ssh2_pkt_addstring_start(void)
1344{
7cca0d81 1345 ssh2_pkt_adduint32(0);
1346 pktout.savedpos = pktout.length;
1347}
32874aea 1348static void ssh2_pkt_addstring_str(char *data)
1349{
7cca0d81 1350 ssh2_pkt_adddata(data, strlen(data));
1351 PUT_32BIT(pktout.data + pktout.savedpos - 4,
32874aea 1352 pktout.length - pktout.savedpos);
7cca0d81 1353}
32874aea 1354static void ssh2_pkt_addstring_data(char *data, int len)
1355{
7cca0d81 1356 ssh2_pkt_adddata(data, len);
1357 PUT_32BIT(pktout.data + pktout.savedpos - 4,
32874aea 1358 pktout.length - pktout.savedpos);
7cca0d81 1359}
32874aea 1360static void ssh2_pkt_addstring(char *data)
1361{
7cca0d81 1362 ssh2_pkt_addstring_start();
1363 ssh2_pkt_addstring_str(data);
1364}
32874aea 1365static char *ssh2_mpint_fmt(Bignum b, int *len)
1366{
7cca0d81 1367 unsigned char *p;
32874aea 1368 int i, n = (bignum_bitcount(b) + 7) / 8;
3709bfe9 1369 p = smalloc(n + 1);
7cca0d81 1370 if (!p)
32874aea 1371 fatalbox("out of memory");
7cca0d81 1372 p[0] = 0;
3709bfe9 1373 for (i = 1; i <= n; i++)
32874aea 1374 p[i] = bignum_byte(b, n - i);
7cca0d81 1375 i = 0;
32874aea 1376 while (i <= n && p[i] == 0 && (p[i + 1] & 0x80) == 0)
1377 i++;
1378 memmove(p, p + i, n + 1 - i);
1379 *len = n + 1 - i;
7cca0d81 1380 return p;
1381}
32874aea 1382static void ssh2_pkt_addmp(Bignum b)
1383{
7cca0d81 1384 unsigned char *p;
1385 int len;
1386 p = ssh2_mpint_fmt(b, &len);
1387 ssh2_pkt_addstring_start();
1388 ssh2_pkt_addstring_data(p, len);
dcbde236 1389 sfree(p);
7cca0d81 1390}
b185170a 1391
1392/*
1393 * Construct an SSH2 final-form packet: compress it, encrypt it,
1394 * put the MAC on it. Final packet, ready to be sent, is stored in
1395 * pktout.data. Total length is returned.
1396 */
32874aea 1397static int ssh2_pkt_construct(void)
1398{
7cca0d81 1399 int cipherblk, maclen, padding, i;
1400 static unsigned long outgoing_sequence = 0;
1401
00db133f 1402 log_packet(PKT_OUTGOING, pktout.data[5], ssh2_pkt_type(pktout.data[5]),
1403 pktout.data + 6, pktout.length - 6);
1404
7cca0d81 1405 /*
4ba9b64b 1406 * Compress packet payload.
1407 */
4ba9b64b 1408 {
1409 unsigned char *newpayload;
1410 int newlen;
32874aea 1411 if (cscomp && cscomp->compress(pktout.data + 5, pktout.length - 5,
4ba9b64b 1412 &newpayload, &newlen)) {
1413 pktout.length = 5;
1414 ssh2_pkt_adddata(newpayload, newlen);
dcbde236 1415 sfree(newpayload);
4ba9b64b 1416 }
1417 }
1418
1419 /*
7cca0d81 1420 * Add padding. At least four bytes, and must also bring total
1421 * length (minus MAC) up to a multiple of the block size.
1422 */
32874aea 1423 cipherblk = cscipher ? cscipher->blksize : 8; /* block size */
1424 cipherblk = cipherblk < 8 ? 8 : cipherblk; /* or 8 if blksize < 8 */
7cca0d81 1425 padding = 4;
32874aea 1426 padding +=
1427 (cipherblk - (pktout.length + padding) % cipherblk) % cipherblk;
783415f8 1428 maclen = csmac ? csmac->len : 0;
1429 ssh2_pkt_ensure(pktout.length + padding + maclen);
7cca0d81 1430 pktout.data[4] = padding;
1431 for (i = 0; i < padding; i++)
32874aea 1432 pktout.data[pktout.length + i] = random_byte();
7cca0d81 1433 PUT_32BIT(pktout.data, pktout.length + padding - 4);
1434 if (csmac)
32874aea 1435 csmac->generate(pktout.data, pktout.length + padding,
1436 outgoing_sequence);
1437 outgoing_sequence++; /* whether or not we MACed */
7cca0d81 1438
7cca0d81 1439 if (cscipher)
32874aea 1440 cscipher->encrypt(pktout.data, pktout.length + padding);
7cca0d81 1441
b185170a 1442 /* Ready-to-send packet starts at pktout.data. We return length. */
1443 return pktout.length + padding + maclen;
1444}
1445
1446/*
1447 * Construct and send an SSH2 packet immediately.
1448 */
32874aea 1449static void ssh2_pkt_send(void)
1450{
5471d09a 1451 int len;
1452 int backlog;
1453 len = ssh2_pkt_construct();
1454 backlog = sk_write(s, pktout.data, len);
1455 if (backlog > SSH_MAX_BACKLOG)
1456 ssh_throttle_all(1, backlog);
b185170a 1457}
1458
1459/*
1460 * Construct an SSH2 packet and add it to a deferred data block.
1461 * Useful for sending multiple packets in a single sk_write() call,
1462 * to prevent a traffic-analysing listener from being able to work
1463 * out the length of any particular packet (such as the password
1464 * packet).
1465 *
1466 * Note that because SSH2 sequence-numbers its packets, this can
1467 * NOT be used as an m4-style `defer' allowing packets to be
1468 * constructed in one order and sent in another.
1469 */
32874aea 1470static void ssh2_pkt_defer(void)
1471{
b185170a 1472 int len = ssh2_pkt_construct();
1473 if (deferred_len + len > deferred_size) {
32874aea 1474 deferred_size = deferred_len + len + 128;
1475 deferred_send_data = srealloc(deferred_send_data, deferred_size);
b185170a 1476 }
32874aea 1477 memcpy(deferred_send_data + deferred_len, pktout.data, len);
b185170a 1478 deferred_len += len;
1479}
1480
1481/*
1482 * Send the whole deferred data block constructed by
39065bed 1483 * ssh2_pkt_defer() or SSH1's defer_packet().
b185170a 1484 */
32874aea 1485static void ssh_pkt_defersend(void)
1486{
5471d09a 1487 int backlog;
1488 backlog = sk_write(s, deferred_send_data, deferred_len);
b185170a 1489 deferred_len = deferred_size = 0;
1490 sfree(deferred_send_data);
1491 deferred_send_data = NULL;
5471d09a 1492 if (backlog > SSH_MAX_BACKLOG)
1493 ssh_throttle_all(1, backlog);
7cca0d81 1494}
1495
1496#if 0
32874aea 1497void bndebug(char *string, Bignum b)
1498{
7cca0d81 1499 unsigned char *p;
1500 int i, len;
1501 p = ssh2_mpint_fmt(b, &len);
1502 debug(("%s", string));
1503 for (i = 0; i < len; i++)
32874aea 1504 debug((" %02x", p[i]));
765c4200 1505 debug(("\n"));
dcbde236 1506 sfree(p);
7cca0d81 1507}
1508#endif
1509
32874aea 1510static void sha_mpint(SHA_State * s, Bignum b)
1511{
7cca0d81 1512 unsigned char *p;
1513 int len;
1514 p = ssh2_mpint_fmt(b, &len);
1515 sha_string(s, p, len);
dcbde236 1516 sfree(p);
7cca0d81 1517}
1518
1519/*
1520 * SSH2 packet decode functions.
1521 */
32874aea 1522static unsigned long ssh2_pkt_getuint32(void)
1523{
7cca0d81 1524 unsigned long value;
1525 if (pktin.length - pktin.savedpos < 4)
32874aea 1526 return 0; /* arrgh, no way to decline (FIXME?) */
1527 value = GET_32BIT(pktin.data + pktin.savedpos);
7cca0d81 1528 pktin.savedpos += 4;
1529 return value;
1530}
32874aea 1531static int ssh2_pkt_getbool(void)
1532{
65a22376 1533 unsigned long value;
1534 if (pktin.length - pktin.savedpos < 1)
32874aea 1535 return 0; /* arrgh, no way to decline (FIXME?) */
65a22376 1536 value = pktin.data[pktin.savedpos] != 0;
1537 pktin.savedpos++;
1538 return value;
1539}
32874aea 1540static void ssh2_pkt_getstring(char **p, int *length)
1541{
7cca0d81 1542 *p = NULL;
1543 if (pktin.length - pktin.savedpos < 4)
32874aea 1544 return;
1545 *length = GET_32BIT(pktin.data + pktin.savedpos);
7cca0d81 1546 pktin.savedpos += 4;
1547 if (pktin.length - pktin.savedpos < *length)
32874aea 1548 return;
1549 *p = pktin.data + pktin.savedpos;
7cca0d81 1550 pktin.savedpos += *length;
1551}
32874aea 1552static Bignum ssh2_pkt_getmp(void)
1553{
7cca0d81 1554 char *p;
3709bfe9 1555 int length;
7cca0d81 1556 Bignum b;
1557
1558 ssh2_pkt_getstring(&p, &length);
1559 if (!p)
32874aea 1560 return NULL;
8d5de777 1561 if (p[0] & 0x80) {
32874aea 1562 bombout(("internal error: Can't handle negative mpints"));
1563 return NULL;
8d5de777 1564 }
3709bfe9 1565 b = bignum_from_bytes(p, length);
7cca0d81 1566 return b;
1567}
1568
7d503c31 1569/*
1570 * Examine the remote side's version string and compare it against
1571 * a list of known buggy implementations.
1572 */
32874aea 1573static void ssh_detect_bugs(char *vstring)
1574{
1575 char *imp; /* pointer to implementation part */
7d503c31 1576 imp = vstring;
1577 imp += strcspn(imp, "-");
bd358db1 1578 if (*imp) imp++;
7d503c31 1579 imp += strcspn(imp, "-");
bd358db1 1580 if (*imp) imp++;
7d503c31 1581
1582 ssh_remote_bugs = 0;
1583
1584 if (!strcmp(imp, "1.2.18") || !strcmp(imp, "1.2.19") ||
32874aea 1585 !strcmp(imp, "1.2.20") || !strcmp(imp, "1.2.21") ||
bd358db1 1586 !strcmp(imp, "1.2.22") || !strcmp(imp, "Cisco-1.25")) {
32874aea 1587 /*
1588 * These versions don't support SSH1_MSG_IGNORE, so we have
1589 * to use a different defence against password length
1590 * sniffing.
1591 */
1592 ssh_remote_bugs |= BUG_CHOKES_ON_SSH1_IGNORE;
1593 logevent("We believe remote version has SSH1 ignore bug");
7d503c31 1594 }
1595
bd358db1 1596 if (!strcmp(imp, "Cisco-1.25")) {
1597 /*
1598 * These versions need a plain password sent; they can't
1599 * handle having a null and a random length of data after
1600 * the password.
1601 */
1602 ssh_remote_bugs |= BUG_NEEDS_SSH1_PLAIN_PASSWORD;
1603 logevent("We believe remote version needs a plain SSH1 password");
1604 }
1605
0df73905 1606 if (!strcmp(imp, "Cisco-1.25")) {
1607 /*
1608 * These versions apparently have no clue whatever about
1609 * RSA authentication and will panic and die if they see
1610 * an AUTH_RSA message.
1611 */
1612 ssh_remote_bugs |= BUG_CHOKES_ON_RSA;
1613 logevent("We believe remote version can't handle RSA authentication");
1614 }
1615
7d503c31 1616 if (!strncmp(imp, "2.1.0", 5) || !strncmp(imp, "2.0.", 4) ||
32874aea 1617 !strncmp(imp, "2.2.0", 5) || !strncmp(imp, "2.3.0", 5) ||
1618 !strncmp(imp, "2.1 ", 4)) {
1619 /*
1620 * These versions have the HMAC bug.
1621 */
1622 ssh_remote_bugs |= BUG_SSH2_HMAC;
1623 logevent("We believe remote version has SSH2 HMAC bug");
7d503c31 1624 }
1625}
1626
32874aea 1627static int do_ssh_init(unsigned char c)
1628{
2d466ffd 1629 static int vslen;
8df7a775 1630 static char version[10];
50526e47 1631 static char *vstring;
1632 static int vstrsize;
1633 static char *vlog;
8df7a775 1634 static int i;
374330e2 1635
8df7a775 1636 crBegin;
1637
1638 /* Search for the string "SSH-" in the input. */
374330e2 1639 i = 0;
8df7a775 1640 while (1) {
1641 static const int transS[] = { 1, 2, 2, 1 };
1642 static const int transH[] = { 0, 0, 3, 0 };
1643 static const int transminus[] = { 0, 0, 0, -1 };
32874aea 1644 if (c == 'S')
1645 i = transS[i];
1646 else if (c == 'H')
1647 i = transH[i];
1648 else if (c == '-')
1649 i = transminus[i];
1650 else
1651 i = 0;
8df7a775 1652 if (i < 0)
1653 break;
1654 crReturn(1); /* get another character */
374330e2 1655 }
8df7a775 1656
50526e47 1657 vstrsize = 16;
bd358db1 1658 vstring = smalloc(vstrsize);
c5e9c988 1659 strcpy(vstring, "SSH-");
50526e47 1660 vslen = 4;
374330e2 1661 i = 0;
1662 while (1) {
8df7a775 1663 crReturn(1); /* get another char */
32874aea 1664 if (vslen >= vstrsize - 1) {
1665 vstrsize += 16;
1666 vstring = srealloc(vstring, vstrsize);
1667 }
1668 vstring[vslen++] = c;
374330e2 1669 if (i >= 0) {
1670 if (c == '-') {
1671 version[i] = '\0';
1672 i = -1;
32874aea 1673 } else if (i < sizeof(version) - 1)
374330e2 1674 version[i++] = c;
32874aea 1675 } else if (c == '\n')
374330e2 1676 break;
1677 }
1678
db7d555c 1679 ssh_agentfwd_enabled = FALSE;
960e736a 1680 rdpkt2_state.incoming_sequence = 0;
1681
50526e47 1682 vstring[vslen] = 0;
9275ca8a 1683 vlog = smalloc(20 + vslen);
bd358db1 1684 vstring[strcspn (vstring, "\r\n")] = '\0'; /* remove end-of-line chars */
c5e9c988 1685 sprintf(vlog, "Server version: %s", vstring);
c5e9c988 1686 logevent(vlog);
bd358db1 1687 ssh_detect_bugs(vstring);
9275ca8a 1688 sfree(vlog);
c5e9c988 1689
adf799dd 1690 /*
1691 * Server version "1.99" means we can choose whether we use v1
1692 * or v2 protocol. Choice is based on cfg.sshprot.
1693 */
1694 if (ssh_versioncmp(version, cfg.sshprot == 1 ? "2.0" : "1.99") >= 0) {
32874aea 1695 /*
1696 * This is a v2 server. Begin v2 protocol.
1697 */
1698 char verstring[80], vlog[100];
1699 sprintf(verstring, "SSH-2.0-%s", sshver);
1700 SHA_Init(&exhashbase);
1701 /*
1702 * Hash our version string and their version string.
1703 */
1704 sha_string(&exhashbase, verstring, strlen(verstring));
1705 sha_string(&exhashbase, vstring, strcspn(vstring, "\r\n"));
1706 sprintf(vlog, "We claim version: %s", verstring);
1707 logevent(vlog);
1708 strcat(verstring, "\n");
1709 logevent("Using SSH protocol version 2");
1710 sk_write(s, verstring, strlen(verstring));
1711 ssh_protocol = ssh2_protocol;
1712 ssh_version = 2;
1713 s_rdpkt = ssh2_rdpkt;
e5574168 1714 } else {
32874aea 1715 /*
1716 * This is a v1 server. Begin v1 protocol.
1717 */
1718 char verstring[80], vlog[100];
1719 sprintf(verstring, "SSH-%s-%s",
1720 (ssh_versioncmp(version, "1.5") <= 0 ? version : "1.5"),
1721 sshver);
1722 sprintf(vlog, "We claim version: %s", verstring);
1723 logevent(vlog);
1724 strcat(verstring, "\n");
759712a6 1725
1726 if (cfg.sshprot == 3) {
1727 bombout(("SSH protocol version 2 required by user but not provided by server"));
1728 crReturn(0);
1729 }
1730
32874aea 1731 logevent("Using SSH protocol version 1");
1732 sk_write(s, verstring, strlen(verstring));
1733 ssh_protocol = ssh1_protocol;
1734 ssh_version = 1;
1735 s_rdpkt = ssh1_rdpkt;
e5574168 1736 }
3687d221 1737 ssh_state = SSH_STATE_BEFORE_SIZE;
8df7a775 1738
50526e47 1739 sfree(vstring);
50526e47 1740
8df7a775 1741 crFinish(0);
1742}
1743
1744static void ssh_gotdata(unsigned char *data, int datalen)
1745{
1746 crBegin;
1747
1748 /*
1749 * To begin with, feed the characters one by one to the
1750 * protocol initialisation / selection function do_ssh_init().
1751 * When that returns 0, we're done with the initial greeting
1752 * exchange and can move on to packet discipline.
1753 */
1754 while (1) {
1755 int ret;
1756 if (datalen == 0)
1757 crReturnV; /* more data please */
1758 ret = do_ssh_init(*data);
32874aea 1759 data++;
1760 datalen--;
8df7a775 1761 if (ret == 0)
1762 break;
1763 }
1764
1765 /*
1766 * We emerge from that loop when the initial negotiation is
1767 * over and we have selected an s_rdpkt function. Now pass
1768 * everything to s_rdpkt, and then pass the resulting packets
1769 * to the proper protocol handler.
1770 */
1771 if (datalen == 0)
1772 crReturnV;
1773 while (1) {
1774 while (datalen > 0) {
32874aea 1775 if (s_rdpkt(&data, &datalen) == 0) {
e14d0f19 1776 if (ssh_state == SSH_STATE_CLOSED) {
1777 return;
1778 }
8df7a775 1779 ssh_protocol(NULL, 0, 1);
1780 if (ssh_state == SSH_STATE_CLOSED) {
1781 return;
1782 }
1783 }
1784 }
1785 crReturnV;
1786 }
1787 crFinishV;
1788}
1789
32874aea 1790static int ssh_closing(Plug plug, char *error_msg, int error_code,
1791 int calling_back)
1792{
7e78000d 1793 ssh_state = SSH_STATE_CLOSED;
f3ab576e 1794 if (s) {
1795 sk_close(s);
1796 s = NULL;
1797 }
7e78000d 1798 if (error_msg) {
32874aea 1799 /* A socket error has occurred. */
247308b5 1800 logevent(error_msg);
32874aea 1801 connection_fatal(error_msg);
7e78000d 1802 } else {
1803 /* Otherwise, the remote side closed the connection normally. */
8df7a775 1804 }
7e78000d 1805 return 0;
1806}
1807
32874aea 1808static int ssh_receive(Plug plug, int urgent, char *data, int len)
1809{
1810 ssh_gotdata(data, len);
3257deae 1811 if (ssh_state == SSH_STATE_CLOSED) {
32874aea 1812 if (s) {
1813 sk_close(s);
1814 s = NULL;
1815 }
1816 return 0;
3257deae 1817 }
fef97f43 1818 return 1;
374330e2 1819}
1820
5471d09a 1821static void ssh_sent(Plug plug, int bufsize)
1822{
1823 /*
1824 * If the send backlog on the SSH socket itself clears, we
1825 * should unthrottle the whole world if it was throttled.
1826 */
1827 if (bufsize < SSH_MAX_BACKLOG)
1828 ssh_throttle_all(0, bufsize);
1829}
1830
fb09bf1c 1831/*
8df7a775 1832 * Connect to specified host and port.
1833 * Returns an error message, or NULL on success.
6e1ebb76 1834 * Also places the canonical host name into `realhost'. It must be
1835 * freed by the caller.
8df7a775 1836 */
2184a5d9 1837static char *connect_to_host(char *host, int port, char **realhost, int nodelay)
8df7a775 1838{
7e78000d 1839 static struct plug_function_table fn_table = {
1840 ssh_closing,
5471d09a 1841 ssh_receive,
1842 ssh_sent,
1843 NULL
7e78000d 1844 }, *fn_table_ptr = &fn_table;
1845
8df7a775 1846 SockAddr addr;
1847 char *err;
1848#ifdef FWHACK
1849 char *FWhost;
1850 int FWport;
1851#endif
1852
32874aea 1853 savedhost = smalloc(1 + strlen(host));
8df7a775 1854 if (!savedhost)
1855 fatalbox("Out of memory");
1856 strcpy(savedhost, host);
1857
1858 if (port < 0)
1859 port = 22; /* default ssh port */
1860 savedport = port;
1861
1862#ifdef FWHACK
1863 FWhost = host;
1864 FWport = port;
1865 host = FWSTR;
1866 port = 23;
1867#endif
1868
1869 /*
1870 * Try to find host.
1871 */
3ad9d396 1872 {
1873 char buf[200];
1874 sprintf(buf, "Looking up host \"%.170s\"", host);
1875 logevent(buf);
1876 }
8df7a775 1877 addr = sk_namelookup(host, realhost);
32874aea 1878 if ((err = sk_addr_error(addr)))
8df7a775 1879 return err;
1880
1881#ifdef FWHACK
6e1ebb76 1882 *realhost = strdup(FWhost);
8df7a775 1883#endif
1884
1885 /*
1886 * Open socket.
1887 */
3ad9d396 1888 {
1889 char buf[200], addrbuf[100];
1890 sk_getaddr(addr, addrbuf, 100);
1891 sprintf(buf, "Connecting to %.100s port %d", addrbuf, port);
1892 logevent(buf);
1893 }
8eebd221 1894 s = new_connection(addr, *realhost, port, 0, 1, nodelay, &fn_table_ptr);
67c4ba2e 1895 if ((err = sk_socket_error(s))) {
1896 s = NULL;
8df7a775 1897 return err;
67c4ba2e 1898 }
8df7a775 1899
1900#ifdef FWHACK
1901 sk_write(s, "connect ", 8);
1902 sk_write(s, FWhost, strlen(FWhost));
1903 {
1904 char buf[20];
1905 sprintf(buf, " %d\n", FWport);
1906 sk_write(s, buf, strlen(buf));
1907 }
1908#endif
1909
1910 return NULL;
1911}
1912
1913/*
5471d09a 1914 * Throttle or unthrottle the SSH connection.
1915 */
1916static void ssh1_throttle(int adjust)
1917{
1918 int old_count = ssh1_throttle_count;
1919 ssh1_throttle_count += adjust;
1920 assert(ssh1_throttle_count >= 0);
1921 if (ssh1_throttle_count && !old_count) {
1922 sk_set_frozen(s, 1);
1923 } else if (!ssh1_throttle_count && old_count) {
1924 sk_set_frozen(s, 0);
1925 }
1926}
1927
1928/*
1929 * Throttle or unthrottle _all_ local data streams (for when sends
1930 * on the SSH connection itself back up).
1931 */
1932static void ssh_throttle_all(int enable, int bufsize)
1933{
1934 int i;
1935 struct ssh_channel *c;
1936
1937 if (enable == ssh_throttled_all)
1938 return;
1939 ssh_throttled_all = enable;
1940 ssh_overall_bufsize = bufsize;
1941 if (!ssh_channels)
1942 return;
1943 for (i = 0; NULL != (c = index234(ssh_channels, i)); i++) {
1944 switch (c->type) {
1945 case CHAN_MAINSESSION:
1946 /*
1947 * This is treated separately, outside the switch.
1948 */
1949 break;
1950 case CHAN_X11:
1951 x11_override_throttle(c->u.x11.s, enable);
1952 break;
1953 case CHAN_AGENT:
1954 /* Agent channels require no buffer management. */
1955 break;
1956 case CHAN_SOCKDATA:
1957 pfd_override_throttle(c->u.x11.s, enable);
1958 break;
1959 }
1960 }
1961}
1962
1963/*
fb09bf1c 1964 * Handle the key exchange and user authentication phases.
1965 */
e5574168 1966static int do_ssh1_login(unsigned char *in, int inlen, int ispkt)
fb09bf1c 1967{
2d466ffd 1968 int i, j;
1969 static int len;
1970 static unsigned char *rsabuf, *keystr1, *keystr2;
374330e2 1971 unsigned char cookie[8];
1972 struct RSAKey servkey, hostkey;
1973 struct MD5Context md5c;
ccbfb941 1974 static unsigned long supported_ciphers_mask, supported_auths_mask;
67b59fbb 1975 static int tried_publickey, tried_agent;
614a20a0 1976 static int tis_auth_refused, ccard_auth_refused;
7cca0d81 1977 static unsigned char session_id[16];
2d466ffd 1978 static int cipher_type;
b585ec46 1979 static char username[100];
396778f1 1980 static void *publickey_blob;
1981 int publickey_bloblen;
374330e2 1982
374330e2 1983 crBegin;
1984
32874aea 1985 if (!ispkt)
1986 crWaitUntil(ispkt);
374330e2 1987
8d5de777 1988 if (pktin.type != SSH1_SMSG_PUBLIC_KEY) {
1989 bombout(("Public key packet not received"));
32874aea 1990 crReturn(0);
8d5de777 1991 }
374330e2 1992
c5e9c988 1993 logevent("Received public keys");
374330e2 1994
c5e9c988 1995 memcpy(cookie, pktin.body, 8);
374330e2 1996
32874aea 1997 i = makekey(pktin.body + 8, &servkey, &keystr1, 0);
1998 j = makekey(pktin.body + 8 + i, &hostkey, &keystr2, 0);
374330e2 1999
c5e9c988 2000 /*
1c2a93c4 2001 * Log the host key fingerprint.
c5e9c988 2002 */
c5e9c988 2003 {
2004 char logmsg[80];
1c2a93c4 2005 logevent("Host key fingerprint is:");
c5e9c988 2006 strcpy(logmsg, " ");
32874aea 2007 hostkey.comment = NULL;
2008 rsa_fingerprint(logmsg + strlen(logmsg),
2009 sizeof(logmsg) - strlen(logmsg), &hostkey);
c5e9c988 2010 logevent(logmsg);
2011 }
2012
32874aea 2013 ssh1_remote_protoflags = GET_32BIT(pktin.body + 8 + i + j);
2014 supported_ciphers_mask = GET_32BIT(pktin.body + 12 + i + j);
2015 supported_auths_mask = GET_32BIT(pktin.body + 16 + i + j);
bea1ef5f 2016
32874aea 2017 ssh1_local_protoflags =
2018 ssh1_remote_protoflags & SSH1_PROTOFLAGS_SUPPORTED;
b96dc54c 2019 ssh1_local_protoflags |= SSH1_PROTOFLAG_SCREEN_NUMBER;
2020
c5e9c988 2021 MD5Init(&md5c);
374330e2 2022 MD5Update(&md5c, keystr2, hostkey.bytes);
2023 MD5Update(&md5c, keystr1, servkey.bytes);
2024 MD5Update(&md5c, pktin.body, 8);
374330e2 2025 MD5Final(session_id, &md5c);
2026
32874aea 2027 for (i = 0; i < 32; i++)
374330e2 2028 session_key[i] = random_byte();
2029
2030 len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
2031
dcbde236 2032 rsabuf = smalloc(len);
374330e2 2033 if (!rsabuf)
2034 fatalbox("Out of memory");
2035
89ee5268 2036 /*
2037 * Verify the host key.
2038 */
2039 {
32874aea 2040 /*
2041 * First format the key into a string.
2042 */
2043 int len = rsastr_len(&hostkey);
2044 char fingerprint[100];
2045 char *keystr = smalloc(len);
2046 if (!keystr)
2047 fatalbox("Out of memory");
2048 rsastr_fmt(keystr, &hostkey);
2049 rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
2050 verify_ssh_host_key(savedhost, savedport, "rsa", keystr,
2051 fingerprint);
2052 sfree(keystr);
2053 }
2054
2055 for (i = 0; i < 32; i++) {
374330e2 2056 rsabuf[i] = session_key[i];
2057 if (i < 16)
2058 rsabuf[i] ^= session_id[i];
2059 }
2060
2061 if (hostkey.bytes > servkey.bytes) {
2062 rsaencrypt(rsabuf, 32, &servkey);
2063 rsaencrypt(rsabuf, servkey.bytes, &hostkey);
2064 } else {
2065 rsaencrypt(rsabuf, 32, &hostkey);
2066 rsaencrypt(rsabuf, hostkey.bytes, &servkey);
2067 }
2068
c5e9c988 2069 logevent("Encrypted session key");
2070
ca20bfcf 2071 {
2072 int cipher_chosen = 0, warn = 0;
2073 char *cipher_string = NULL;
2074 for (i = 0; !cipher_chosen && i < CIPHER_MAX; i++) {
2075 int next_cipher = cfg.ssh_cipherlist[i];
2076 if (next_cipher == CIPHER_WARN) {
2077 /* If/when we choose a cipher, warn about it */
2078 warn = 1;
2079 } else if (next_cipher == CIPHER_AES) {
2080 /* XXX Probably don't need to mention this. */
2081 logevent("AES not supported in SSH1, skipping");
2082 } else {
2083 switch (next_cipher) {
2084 case CIPHER_3DES: cipher_type = SSH_CIPHER_3DES;
2085 cipher_string = "3DES"; break;
2086 case CIPHER_BLOWFISH: cipher_type = SSH_CIPHER_BLOWFISH;
2087 cipher_string = "Blowfish"; break;
2088 case CIPHER_DES: cipher_type = SSH_CIPHER_DES;
2089 cipher_string = "single-DES"; break;
2090 }
2091 if (supported_ciphers_mask & (1 << cipher_type))
2092 cipher_chosen = 1;
2093 }
2094 }
2095 if (!cipher_chosen) {
2096 if ((supported_ciphers_mask & (1 << SSH_CIPHER_3DES)) == 0)
2097 bombout(("Server violates SSH 1 protocol by not "
2098 "supporting 3DES encryption"));
2099 else
2100 /* shouldn't happen */
2101 bombout(("No supported ciphers found"));
a99a05c0 2102 crReturn(0);
2103 }
ca20bfcf 2104
2105 /* Warn about chosen cipher if necessary. */
2106 if (warn)
2107 askcipher(cipher_string, 0);
bea1ef5f 2108 }
ca20bfcf 2109
c5e9c988 2110 switch (cipher_type) {
32874aea 2111 case SSH_CIPHER_3DES:
2112 logevent("Using 3DES encryption");
2113 break;
2114 case SSH_CIPHER_DES:
2115 logevent("Using single-DES encryption");
2116 break;
2117 case SSH_CIPHER_BLOWFISH:
2118 logevent("Using Blowfish encryption");
2119 break;
c5e9c988 2120 }
bea1ef5f 2121
e5574168 2122 send_packet(SSH1_CMSG_SESSION_KEY,
32874aea 2123 PKT_CHAR, cipher_type,
2124 PKT_DATA, cookie, 8,
2125 PKT_CHAR, (len * 8) >> 8, PKT_CHAR, (len * 8) & 0xFF,
2126 PKT_DATA, rsabuf, len,
2127 PKT_INT, ssh1_local_protoflags, PKT_END);
fb09bf1c 2128
c5e9c988 2129 logevent("Trying to enable encryption...");
374330e2 2130
dcbde236 2131 sfree(rsabuf);
374330e2 2132
5e8358ad 2133 cipher = cipher_type == SSH_CIPHER_BLOWFISH ? &ssh_blowfish_ssh1 :
32874aea 2134 cipher_type == SSH_CIPHER_DES ? &ssh_des : &ssh_3des;
374330e2 2135 cipher->sesskey(session_key);
2136
fb09bf1c 2137 crWaitUntil(ispkt);
374330e2 2138
8d5de777 2139 if (pktin.type != SSH1_SMSG_SUCCESS) {
2140 bombout(("Encryption not successfully enabled"));
32874aea 2141 crReturn(0);
8d5de777 2142 }
374330e2 2143
c5e9c988 2144 logevent("Successfully started encryption");
2145
374330e2 2146 fflush(stdout);
2147 {
374330e2 2148 static int pos = 0;
2149 static char c;
67779be7 2150 if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
32874aea 2151 if (ssh_get_line) {
2152 if (!ssh_get_line("login as: ",
2153 username, sizeof(username), FALSE)) {
2154 /*
2155 * get_line failed to get a username.
2156 * Terminate.
2157 */
2158 logevent("No username provided. Abandoning session.");
2159 ssh_state = SSH_STATE_CLOSED;
2160 crReturn(1);
2161 }
2162 } else {
2163 c_write_str("login as: ");
2164 ssh_send_ok = 1;
2165 while (pos >= 0) {
2166 crWaitUntil(!ispkt);
2167 while (inlen--)
2168 switch (c = *in++) {
2169 case 10:
2170 case 13:
2171 username[pos] = 0;
2172 pos = -1;
2173 break;
2174 case 8:
2175 case 127:
2176 if (pos > 0) {
2177 c_write_str("\b \b");
2178 pos--;
2179 }
2180 break;
2181 case 21:
2182 case 27:
2183 while (pos > 0) {
2184 c_write_str("\b \b");
2185 pos--;
2186 }
2187 break;
2188 case 3:
2189 case 4:
93b581bd 2190 cleanup_exit(0);
32874aea 2191 break;
2192 default:
2193 if (((c >= ' ' && c <= '~') ||
51b2fb65 2194 ((unsigned char) c >= 160))
2195 && pos < sizeof(username)-1) {
32874aea 2196 username[pos++] = c;
2197 c_write(&c, 1);
2198 }
2199 break;
2200 }
2201 }
2202 c_write_str("\r\n");
2203 username[strcspn(username, "\n\r")] = '\0';
2204 }
2205 } else {
374330e2 2206 strncpy(username, cfg.username, 99);
2207 username[99] = '\0';
374330e2 2208 }
fb09bf1c 2209
e5574168 2210 send_packet(SSH1_CMSG_USER, PKT_STR, username, PKT_END);
c5e9c988 2211 {
32874aea 2212 char userlog[22 + sizeof(username)];
c5e9c988 2213 sprintf(userlog, "Sent username \"%s\"", username);
2214 logevent(userlog);
32874aea 2215 if (flags & FLAG_INTERACTIVE &&
2216 (!((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)))) {
3c8e959b 2217 strcat(userlog, "\r\n");
32874aea 2218 c_write_str(userlog);
3c8e959b 2219 }
c5e9c988 2220 }
374330e2 2221 }
2222
fb09bf1c 2223 crWaitUntil(ispkt);
374330e2 2224
0df73905 2225 if ((ssh_remote_bugs & BUG_CHOKES_ON_RSA)) {
2226 /* We must not attempt PK auth. Pretend we've already tried it. */
2227 tried_publickey = tried_agent = 1;
2228 } else {
2229 tried_publickey = tried_agent = 0;
2230 }
614a20a0 2231 tis_auth_refused = ccard_auth_refused = 0;
396778f1 2232 /* Load the public half of cfg.keyfile so we notice if it's in Pageant */
2233 if (*cfg.keyfile) {
2234 if (!rsakey_pubblob(cfg.keyfile, &publickey_blob, &publickey_bloblen))
2235 publickey_blob = NULL;
2236 } else
2237 publickey_blob = NULL;
7cca0d81 2238
e5574168 2239 while (pktin.type == SSH1_SMSG_FAILURE) {
374330e2 2240 static char password[100];
a52f067e 2241 static char prompt[200];
374330e2 2242 static int pos;
2243 static char c;
32874aea 2244 static int pwpkt_type;
32874aea 2245 pwpkt_type = SSH1_CMSG_AUTH_PASSWORD;
614a20a0 2246
67b59fbb 2247 if (agent_exists() && !tried_agent) {
32874aea 2248 /*
2249 * Attempt RSA authentication using Pageant.
2250 */
2251 static unsigned char request[5], *response, *p;
2252 static int responselen;
2253 static int i, nkeys;
2254 static int authed = FALSE;
2255 void *r;
2256
67b59fbb 2257 tried_agent = 1;
32874aea 2258 logevent("Pageant is running. Requesting keys.");
2259
2260 /* Request the keys held by the agent. */
2261 PUT_32BIT(request, 1);
2262 request[4] = SSH1_AGENTC_REQUEST_RSA_IDENTITIES;
2263 agent_query(request, 5, &r, &responselen);
2264 response = (unsigned char *) r;
2265 if (response && responselen >= 5 &&
2266 response[4] == SSH1_AGENT_RSA_IDENTITIES_ANSWER) {
2267 p = response + 5;
2268 nkeys = GET_32BIT(p);
2269 p += 4;
2270 {
2271 char buf[64];
2272 sprintf(buf, "Pageant has %d SSH1 keys", nkeys);
2273 logevent(buf);
2274 }
2275 for (i = 0; i < nkeys; i++) {
2276 static struct RSAKey key;
2277 static Bignum challenge;
2278 static char *commentp;
2279 static int commentlen;
2280
2281 {
2282 char buf[64];
2283 sprintf(buf, "Trying Pageant key #%d", i);
2284 logevent(buf);
2285 }
396778f1 2286 if (publickey_blob &&
2287 !memcmp(p, publickey_blob, publickey_bloblen)) {
2288 logevent("This key matches configured key file");
2289 tried_publickey = 1;
2290 }
32874aea 2291 p += 4;
2292 p += ssh1_read_bignum(p, &key.exponent);
2293 p += ssh1_read_bignum(p, &key.modulus);
2294 commentlen = GET_32BIT(p);
2295 p += 4;
2296 commentp = p;
2297 p += commentlen;
2298 send_packet(SSH1_CMSG_AUTH_RSA,
2299 PKT_BIGNUM, key.modulus, PKT_END);
2300 crWaitUntil(ispkt);
2301 if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
2302 logevent("Key refused");
2303 continue;
2304 }
2305 logevent("Received RSA challenge");
2306 ssh1_read_bignum(pktin.body, &challenge);
2307 {
2308 char *agentreq, *q, *ret;
2d466ffd 2309 void *vret;
32874aea 2310 int len, retlen;
2311 len = 1 + 4; /* message type, bit count */
2312 len += ssh1_bignum_length(key.exponent);
2313 len += ssh1_bignum_length(key.modulus);
2314 len += ssh1_bignum_length(challenge);
2315 len += 16; /* session id */
2316 len += 4; /* response format */
2317 agentreq = smalloc(4 + len);
2318 PUT_32BIT(agentreq, len);
2319 q = agentreq + 4;
2320 *q++ = SSH1_AGENTC_RSA_CHALLENGE;
2321 PUT_32BIT(q, bignum_bitcount(key.modulus));
2322 q += 4;
2323 q += ssh1_write_bignum(q, key.exponent);
2324 q += ssh1_write_bignum(q, key.modulus);
2325 q += ssh1_write_bignum(q, challenge);
2326 memcpy(q, session_id, 16);
2327 q += 16;
2328 PUT_32BIT(q, 1); /* response format */
2d466ffd 2329 agent_query(agentreq, len + 4, &vret, &retlen);
2330 ret = vret;
32874aea 2331 sfree(agentreq);
2332 if (ret) {
2333 if (ret[4] == SSH1_AGENT_RSA_RESPONSE) {
2334 logevent("Sending Pageant's response");
2335 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
2336 PKT_DATA, ret + 5, 16,
2337 PKT_END);
2338 sfree(ret);
2339 crWaitUntil(ispkt);
2340 if (pktin.type == SSH1_SMSG_SUCCESS) {
2341 logevent
2342 ("Pageant's response accepted");
2343 if (flags & FLAG_VERBOSE) {
2344 c_write_str
2345 ("Authenticated using RSA key \"");
2346 c_write(commentp, commentlen);
2347 c_write_str("\" from agent\r\n");
2348 }
2349 authed = TRUE;
2350 } else
2351 logevent
2352 ("Pageant's response not accepted");
2353 } else {
2354 logevent
2355 ("Pageant failed to answer challenge");
2356 sfree(ret);
2357 }
2358 } else {
2359 logevent("No reply received from Pageant");
2360 }
2361 }
2362 freebn(key.exponent);
2363 freebn(key.modulus);
2364 freebn(challenge);
2365 if (authed)
2366 break;
2367 }
2368 }
2369 if (authed)
2370 break;
2371 }
2372 if (*cfg.keyfile && !tried_publickey)
2373 pwpkt_type = SSH1_CMSG_AUTH_RSA;
2374
614a20a0 2375 if (cfg.try_tis_auth &&
2376 (supported_auths_mask & (1 << SSH1_AUTH_TIS)) &&
2377 !tis_auth_refused) {
32874aea 2378 pwpkt_type = SSH1_CMSG_AUTH_TIS_RESPONSE;
2379 logevent("Requested TIS authentication");
2380 send_packet(SSH1_CMSG_AUTH_TIS, PKT_END);
2381 crWaitUntil(ispkt);
2382 if (pktin.type != SSH1_SMSG_AUTH_TIS_CHALLENGE) {
2383 logevent("TIS authentication declined");
2384 if (flags & FLAG_INTERACTIVE)
2385 c_write_str("TIS authentication refused.\r\n");
614a20a0 2386 tis_auth_refused = 1;
2387 continue;
32874aea 2388 } else {
2389 int challengelen = ((pktin.body[0] << 24) |
2390 (pktin.body[1] << 16) |
2391 (pktin.body[2] << 8) |
2392 (pktin.body[3]));
2393 logevent("Received TIS challenge");
2394 if (challengelen > sizeof(prompt) - 1)
2395 challengelen = sizeof(prompt) - 1; /* prevent overrun */
2396 memcpy(prompt, pktin.body + 4, challengelen);
614a20a0 2397 /* Prompt heuristic comes from OpenSSH */
2398 strncpy(prompt + challengelen,
2399 memchr(prompt, '\n', challengelen) ?
2400 "": "\r\nResponse: ",
2401 (sizeof prompt) - challengelen);
2402 prompt[(sizeof prompt) - 1] = '\0';
32874aea 2403 }
2404 }
614a20a0 2405 if (cfg.try_tis_auth &&
2406 (supported_auths_mask & (1 << SSH1_AUTH_CCARD)) &&
2407 !ccard_auth_refused) {
32874aea 2408 pwpkt_type = SSH1_CMSG_AUTH_CCARD_RESPONSE;
2409 logevent("Requested CryptoCard authentication");
2410 send_packet(SSH1_CMSG_AUTH_CCARD, PKT_END);
2411 crWaitUntil(ispkt);
2412 if (pktin.type != SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
2413 logevent("CryptoCard authentication declined");
2414 c_write_str("CryptoCard authentication refused.\r\n");
614a20a0 2415 ccard_auth_refused = 1;
2416 continue;
32874aea 2417 } else {
2418 int challengelen = ((pktin.body[0] << 24) |
2419 (pktin.body[1] << 16) |
2420 (pktin.body[2] << 8) |
2421 (pktin.body[3]));
2422 logevent("Received CryptoCard challenge");
2423 if (challengelen > sizeof(prompt) - 1)
2424 challengelen = sizeof(prompt) - 1; /* prevent overrun */
2425 memcpy(prompt, pktin.body + 4, challengelen);
614a20a0 2426 strncpy(prompt + challengelen,
2427 memchr(prompt, '\n', challengelen) ?
2428 "" : "\r\nResponse: ",
32874aea 2429 sizeof(prompt) - challengelen);
2430 prompt[sizeof(prompt) - 1] = '\0';
2431 }
2432 }
2433 if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
2434 sprintf(prompt, "%.90s@%.90s's password: ",
2435 username, savedhost);
2436 }
2437 if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
2438 char *comment = NULL;
231ee168 2439 int type;
2440 char msgbuf[256];
32874aea 2441 if (flags & FLAG_VERBOSE)
2442 c_write_str("Trying public key authentication.\r\n");
231ee168 2443 sprintf(msgbuf, "Trying public key \"%.200s\"", cfg.keyfile);
2444 logevent(msgbuf);
2445 type = key_type(cfg.keyfile);
2446 if (type != SSH_KEYTYPE_SSH1) {
2447 sprintf(msgbuf, "Key is of wrong type (%s)",
2448 key_type_to_str(type));
2449 logevent(msgbuf);
2450 c_write_str(msgbuf);
2451 c_write_str("\r\n");
2452 tried_publickey = 1;
2453 continue;
2454 }
32874aea 2455 if (!rsakey_encrypted(cfg.keyfile, &comment)) {
2456 if (flags & FLAG_VERBOSE)
2457 c_write_str("No passphrase required.\r\n");
2458 goto tryauth;
2459 }
2460 sprintf(prompt, "Passphrase for key \"%.100s\": ", comment);
2461 sfree(comment);
2462 }
a52f067e 2463
614a20a0 2464 /*
2465 * Show password prompt, having first obtained it via a TIS
2466 * or CryptoCard exchange if we're doing TIS or CryptoCard
2467 * authentication.
2468 */
fa17a66e 2469 if (ssh_get_line) {
2470 if (!ssh_get_line(prompt, password, sizeof(password), TRUE)) {
32874aea 2471 /*
2472 * get_line failed to get a password (for example
2473 * because one was supplied on the command line
2474 * which has already failed to work). Terminate.
2475 */
2bc6a386 2476 send_packet(SSH1_MSG_DISCONNECT,
2477 PKT_STR, "No more passwords available to try",
2478 PKT_END);
247308b5 2479 logevent("Unable to authenticate");
2bc6a386 2480 connection_fatal("Unable to authenticate");
32874aea 2481 ssh_state = SSH_STATE_CLOSED;
2482 crReturn(1);
2483 }
fb09bf1c 2484 } else {
614a20a0 2485 /* Prompt may have come from server. We've munged it a bit, so
2486 * we know it to be zero-terminated at least once. */
2487 c_write_untrusted(prompt, strlen(prompt));
32874aea 2488 pos = 0;
2489 ssh_send_ok = 1;
2490 while (pos >= 0) {
2491 crWaitUntil(!ispkt);
2492 while (inlen--)
2493 switch (c = *in++) {
2494 case 10:
2495 case 13:
2496 password[pos] = 0;
2497 pos = -1;
2498 break;
2499 case 8:
2500 case 127:
2501 if (pos > 0)
2502 pos--;
2503 break;
2504 case 21:
2505 case 27:
2506 pos = 0;
2507 break;
2508 case 3:
2509 case 4:
93b581bd 2510 cleanup_exit(0);
32874aea 2511 break;
2512 default:
51b2fb65 2513 if (pos < sizeof(password)-1)
32874aea 2514 password[pos++] = c;
2515 break;
2516 }
2517 }
2518 c_write_str("\r\n");
2519 }
2520
2521 tryauth:
7cca0d81 2522 if (pwpkt_type == SSH1_CMSG_AUTH_RSA) {
32874aea 2523 /*
2524 * Try public key authentication with the specified
2525 * key file.
2526 */
2527 static struct RSAKey pubkey;
2528 static Bignum challenge, response;
2529 static int i;
2530 static unsigned char buffer[32];
2531
2532 tried_publickey = 1;
2533 i = loadrsakey(cfg.keyfile, &pubkey, password);
2534 if (i == 0) {
7963af2f 2535 c_write_str("Couldn't load private key from ");
32874aea 2536 c_write_str(cfg.keyfile);
2537 c_write_str(".\r\n");
2538 continue; /* go and try password */
2539 }
2540 if (i == -1) {
2541 c_write_str("Wrong passphrase.\r\n");
2542 tried_publickey = 0;
2543 continue; /* try again */
2544 }
2545
2546 /*
2547 * Send a public key attempt.
2548 */
2549 send_packet(SSH1_CMSG_AUTH_RSA,
2550 PKT_BIGNUM, pubkey.modulus, PKT_END);
2551
2552 crWaitUntil(ispkt);
2553 if (pktin.type == SSH1_SMSG_FAILURE) {
2554 c_write_str("Server refused our public key.\r\n");
2555 continue; /* go and try password */
2556 }
2557 if (pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
2558 bombout(("Bizarre response to offer of public key"));
2559 crReturn(0);
2560 }
2561 ssh1_read_bignum(pktin.body, &challenge);
2562 response = rsadecrypt(challenge, &pubkey);
2563 freebn(pubkey.private_exponent); /* burn the evidence */
2564
2565 for (i = 0; i < 32; i++) {
2566 buffer[i] = bignum_byte(response, 31 - i);
2567 }
2568
2569 MD5Init(&md5c);
2570 MD5Update(&md5c, buffer, 32);
2571 MD5Update(&md5c, session_id, 16);
2572 MD5Final(buffer, &md5c);
2573
2574 send_packet(SSH1_CMSG_AUTH_RSA_RESPONSE,
2575 PKT_DATA, buffer, 16, PKT_END);
2576
2577 crWaitUntil(ispkt);
2578 if (pktin.type == SSH1_SMSG_FAILURE) {
2579 if (flags & FLAG_VERBOSE)
2580 c_write_str
2581 ("Failed to authenticate with our public key.\r\n");
2582 continue; /* go and try password */
2583 } else if (pktin.type != SSH1_SMSG_SUCCESS) {
2584 bombout(
2585 ("Bizarre response to RSA authentication response"));
2586 crReturn(0);
2587 }
2588
2589 break; /* we're through! */
2590 } else {
2591 if (pwpkt_type == SSH1_CMSG_AUTH_PASSWORD) {
2592 /*
2593 * Defence against traffic analysis: we send a
2594 * whole bunch of packets containing strings of
2595 * different lengths. One of these strings is the
2596 * password, in a SSH1_CMSG_AUTH_PASSWORD packet.
2597 * The others are all random data in
2598 * SSH1_MSG_IGNORE packets. This way a passive
2599 * listener can't tell which is the password, and
2600 * hence can't deduce the password length.
2601 *
2602 * Anybody with a password length greater than 16
2603 * bytes is going to have enough entropy in their
2604 * password that a listener won't find it _that_
2605 * much help to know how long it is. So what we'll
2606 * do is:
2607 *
2608 * - if password length < 16, we send 15 packets
2609 * containing string lengths 1 through 15
2610 *
2611 * - otherwise, we let N be the nearest multiple
2612 * of 8 below the password length, and send 8
2613 * packets containing string lengths N through
2614 * N+7. This won't obscure the order of
2615 * magnitude of the password length, but it will
2616 * introduce a bit of extra uncertainty.
2617 *
2618 * A few servers (the old 1.2.18 through 1.2.22)
2619 * can't deal with SSH1_MSG_IGNORE. For these
2620 * servers, we need an alternative defence. We make
2621 * use of the fact that the password is interpreted
2622 * as a C string: so we can append a NUL, then some
2623 * random data.
bd358db1 2624 *
2625 * One server (a Cisco one) can deal with neither
2626 * SSH1_MSG_IGNORE _nor_ a padded password string.
2627 * For this server we are left with no defences
2628 * against password length sniffing.
32874aea 2629 */
bd358db1 2630 if (!(ssh_remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE)) {
b17c8428 2631 /*
2632 * The server can deal with SSH1_MSG_IGNORE, so
2633 * we can use the primary defence.
2634 */
32874aea 2635 int bottom, top, pwlen, i;
2636 char *randomstr;
2637
2638 pwlen = strlen(password);
2639 if (pwlen < 16) {
2640 bottom = 0; /* zero length passwords are OK! :-) */
2641 top = 15;
2642 } else {
2643 bottom = pwlen & ~7;
2644 top = bottom + 7;
2645 }
2646
2647 assert(pwlen >= bottom && pwlen <= top);
2648
2649 randomstr = smalloc(top + 1);
2650
2651 for (i = bottom; i <= top; i++) {
2652 if (i == pwlen)
2653 defer_packet(pwpkt_type, PKT_STR, password,
2654 PKT_END);
2655 else {
2656 for (j = 0; j < i; j++) {
2657 do {
2658 randomstr[j] = random_byte();
2659 } while (randomstr[j] == '\0');
2660 }
2661 randomstr[i] = '\0';
2662 defer_packet(SSH1_MSG_IGNORE,
2663 PKT_STR, randomstr, PKT_END);
2664 }
2665 }
bd358db1 2666 logevent("Sending password with camouflage packets");
32874aea 2667 ssh_pkt_defersend();
bd358db1 2668 }
2669 else if (!(ssh_remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
b17c8428 2670 /*
2671 * The server can't deal with SSH1_MSG_IGNORE
2672 * but can deal with padded passwords, so we
2673 * can use the secondary defence.
2674 */
bd358db1 2675 char string[64];
2676 char *s;
2677 int len;
2678
2679 len = strlen(password);
2680 if (len < sizeof(string)) {
2681 s = string;
2682 strcpy(string, password);
2683 len++; /* cover the zero byte */
2684 while (len < sizeof(string)) {
2685 string[len++] = (char) random_byte();
2686 }
2687 } else {
2688 s = password;
2689 }
2690 logevent("Sending length-padded password");
2691 send_packet(pwpkt_type, PKT_INT, len,
2692 PKT_DATA, s, len, PKT_END);
2693 } else {
2694 /*
2695 * The server has _both_
2696 * BUG_CHOKES_ON_SSH1_IGNORE and
2697 * BUG_NEEDS_SSH1_PLAIN_PASSWORD. There is
2698 * therefore nothing we can do.
2699 */
2700 int len;
2701 len = strlen(password);
2702 logevent("Sending unpadded password");
2703 send_packet(pwpkt_type, PKT_INT, len,
2704 PKT_DATA, password, len, PKT_END);
32874aea 2705 }
2706 } else {
2707 send_packet(pwpkt_type, PKT_STR, password, PKT_END);
2708 }
2709 }
c5e9c988 2710 logevent("Sent password");
374330e2 2711 memset(password, 0, strlen(password));
fb09bf1c 2712 crWaitUntil(ispkt);
e5574168 2713 if (pktin.type == SSH1_SMSG_FAILURE) {
32874aea 2714 if (flags & FLAG_VERBOSE)
2715 c_write_str("Access denied\r\n");
c5e9c988 2716 logevent("Authentication refused");
e5574168 2717 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
fb09bf1c 2718 logevent("Received disconnect request");
32874aea 2719 ssh_state = SSH_STATE_CLOSED;
85ee8208 2720 crReturn(1);
e5574168 2721 } else if (pktin.type != SSH1_SMSG_SUCCESS) {
8d5de777 2722 bombout(("Strange packet received, type %d", pktin.type));
32874aea 2723 crReturn(0);
374330e2 2724 }
2725 }
2726
c5e9c988 2727 logevent("Authentication successful");
2728
fb09bf1c 2729 crFinish(1);
2730}
2731
32874aea 2732void sshfwd_close(struct ssh_channel *c)
2733{
80e48603 2734 if (c && !c->closes) {
4ed34d25 2735 /*
2736 * If the channel's remoteid is -1, we have sent
2737 * CHANNEL_OPEN for this channel, but it hasn't even been
2738 * acknowledged by the server. So we must set a close flag
2739 * on it now, and then when the server acks the channel
2740 * open, we can close it then.
2741 */
36cac739 2742 if (((int)c->remoteid) != -1) {
4ed34d25 2743 if (ssh_version == 1) {
2744 send_packet(SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid,
2745 PKT_END);
2746 } else {
2747 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
2748 ssh2_pkt_adduint32(c->remoteid);
2749 ssh2_pkt_send();
2750 }
32874aea 2751 }
2752 c->closes = 1;
2753 if (c->type == CHAN_X11) {
2754 c->u.x11.s = NULL;
d74d141c 2755 logevent("Forwarded X11 connection terminated");
4ed34d25 2756 } else if (c->type == CHAN_SOCKDATA ||
2757 c->type == CHAN_SOCKDATA_DORMANT) {
d74d141c 2758 c->u.pfd.s = NULL;
2759 logevent("Forwarded port closed");
32874aea 2760 }
2761 }
2762}
2763
5471d09a 2764int sshfwd_write(struct ssh_channel *c, char *buf, int len)
32874aea 2765{
783415f8 2766 if (ssh_version == 1) {
32874aea 2767 send_packet(SSH1_MSG_CHANNEL_DATA,
2768 PKT_INT, c->remoteid,
2769 PKT_INT, len, PKT_DATA, buf, len, PKT_END);
5471d09a 2770 /*
2771 * In SSH1 we can return 0 here - implying that forwarded
2772 * connections are never individually throttled - because
2773 * the only circumstance that can cause throttling will be
2774 * the whole SSH connection backing up, in which case
2775 * _everything_ will be throttled as a whole.
2776 */
2777 return 0;
783415f8 2778 } else {
32874aea 2779 ssh2_add_channel_data(c, buf, len);
5471d09a 2780 return ssh2_try_send(c);
2781 }
2782}
2783
2784void sshfwd_unthrottle(struct ssh_channel *c, int bufsize)
2785{
2786 if (ssh_version == 1) {
2787 if (c->v.v1.throttling && bufsize < SSH1_BUFFER_LIMIT) {
2788 c->v.v1.throttling = 0;
2789 ssh1_throttle(-1);
2790 }
2791 } else {
2792 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
783415f8 2793 }
9c964e85 2794}
2795
32874aea 2796static void ssh1_protocol(unsigned char *in, int inlen, int ispkt)
2797{
fb09bf1c 2798 crBegin;
2799
2800 random_init();
2801
e5574168 2802 while (!do_ssh1_login(in, inlen, ispkt)) {
fb09bf1c 2803 crReturnV;
85ee8208 2804 }
2805 if (ssh_state == SSH_STATE_CLOSED)
32874aea 2806 crReturnV;
fb09bf1c 2807
979310f1 2808 if (cfg.agentfwd && agent_exists()) {
32874aea 2809 logevent("Requesting agent forwarding");
2810 send_packet(SSH1_CMSG_AGENT_REQUEST_FORWARDING, PKT_END);
2811 do {
2812 crReturnV;
2813 } while (!ispkt);
2814 if (pktin.type != SSH1_SMSG_SUCCESS
2815 && pktin.type != SSH1_SMSG_FAILURE) {
2816 bombout(("Protocol confusion"));
2817 crReturnV;
2818 } else if (pktin.type == SSH1_SMSG_FAILURE) {
2819 logevent("Agent forwarding refused");
2820 } else {
2821 logevent("Agent forwarding enabled");
db7d555c 2822 ssh_agentfwd_enabled = TRUE;
2823 }
dacbd0e8 2824 }
2825
9c964e85 2826 if (cfg.x11_forward) {
32874aea 2827 char proto[20], data[64];
2828 logevent("Requesting X11 forwarding");
2829 x11_invent_auth(proto, sizeof(proto), data, sizeof(data));
2830 if (ssh1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) {
2831 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING,
2832 PKT_STR, proto, PKT_STR, data,
2833 PKT_INT, 0, PKT_END);
2834 } else {
2835 send_packet(SSH1_CMSG_X11_REQUEST_FORWARDING,
2836 PKT_STR, proto, PKT_STR, data, PKT_END);
2837 }
2838 do {
2839 crReturnV;
2840 } while (!ispkt);
2841 if (pktin.type != SSH1_SMSG_SUCCESS
2842 && pktin.type != SSH1_SMSG_FAILURE) {
2843 bombout(("Protocol confusion"));
2844 crReturnV;
2845 } else if (pktin.type == SSH1_SMSG_FAILURE) {
2846 logevent("X11 forwarding refused");
2847 } else {
2848 logevent("X11 forwarding enabled");
9c964e85 2849 ssh_X11_fwd_enabled = TRUE;
2850 }
2851 }
2852
d74d141c 2853 {
9bf696b1 2854 char type;
2855 static char *e;
d74d141c 2856 int n;
a4fc0d74 2857 int sport,dport,sserv,dserv;
d74d141c 2858 char sports[256], dports[256], host[256];
2859 char buf[1024];
a4fc0d74 2860 struct servent *se;
d74d141c 2861
bc240b21 2862 ssh_rportfwds = newtree234(ssh_rportcmp_ssh1);
d74d141c 2863 /* Add port forwardings. */
2864 e = cfg.portfwd;
2865 while (*e) {
2866 type = *e++;
2867 n = 0;
2868 while (*e && *e != '\t')
2869 sports[n++] = *e++;
2870 sports[n] = 0;
2871 if (*e == '\t')
2872 e++;
2873 n = 0;
2874 while (*e && *e != ':')
2875 host[n++] = *e++;
2876 host[n] = 0;
2877 if (*e == ':')
2878 e++;
2879 n = 0;
2880 while (*e)
2881 dports[n++] = *e++;
2882 dports[n] = 0;
2883 e++;
2884 dport = atoi(dports);
a4fc0d74 2885 dserv = 0;
2886 if (dport == 0) {
2887 dserv = 1;
2888 se = getservbyname(dports, NULL);
2889 if (se != NULL) {
2890 dport = ntohs(se->s_port);
2891 } else {
2892 sprintf(buf,
2893 "Service lookup failed for destination port \"%s\"",
2894 dports);
2895 logevent(buf);
2896 }
2897 }
d74d141c 2898 sport = atoi(sports);
a4fc0d74 2899 sserv = 0;
2900 if (sport == 0) {
2901 sserv = 1;
2902 se = getservbyname(sports, NULL);
2903 if (se != NULL) {
2904 sport = ntohs(se->s_port);
2905 } else {
2906 sprintf(buf,
2907 "Service lookup failed for source port \"%s\"",
2908 sports);
2909 logevent(buf);
2910 }
2911 }
d74d141c 2912 if (sport && dport) {
2913 if (type == 'L') {
2914 pfd_addforward(host, dport, sport);
a4fc0d74 2915 sprintf(buf, "Local port %.*s%.*s%d%.*s forwarding to"
2916 " %s:%.*s%.*s%d%.*s",
2917 sserv ? strlen(sports) : 0, sports,
2918 sserv, "(", sport, sserv, ")",
2919 host,
2920 dserv ? strlen(dports) : 0, dports,
2921 dserv, "(", dport, dserv, ")");
d74d141c 2922 logevent(buf);
2923 } else {
2924 struct ssh_rportfwd *pf;
2925 pf = smalloc(sizeof(*pf));
bc240b21 2926 strcpy(pf->dhost, host);
2927 pf->dport = dport;
d74d141c 2928 if (add234(ssh_rportfwds, pf) != pf) {
2929 sprintf(buf,
95bc8819 2930 "Duplicate remote port forwarding to %s:%d",
d74d141c 2931 host, dport);
2932 logevent(buf);
bc240b21 2933 sfree(pf);
d74d141c 2934 } else {
a4fc0d74 2935 sprintf(buf, "Requesting remote port %.*s%.*s%d%.*s"
2936 " forward to %s:%.*s%.*s%d%.*s",
2937 sserv ? strlen(sports) : 0, sports,
2938 sserv, "(", sport, sserv, ")",
2939 host,
2940 dserv ? strlen(dports) : 0, dports,
2941 dserv, "(", dport, dserv, ")");
d74d141c 2942 logevent(buf);
2943 send_packet(SSH1_CMSG_PORT_FORWARD_REQUEST,
2944 PKT_INT, sport,
2945 PKT_STR, host,
2946 PKT_INT, dport,
2947 PKT_END);
9bf696b1 2948 do {
2949 crReturnV;
2950 } while (!ispkt);
2951 if (pktin.type != SSH1_SMSG_SUCCESS
2952 && pktin.type != SSH1_SMSG_FAILURE) {
2953 bombout(("Protocol confusion"));
2954 crReturnV;
2955 } else if (pktin.type == SSH1_SMSG_FAILURE) {
2956 c_write_str("Server refused port forwarding\r\n");
2957 ssh_editing = ssh_echoing = 1;
2958 }
2959 logevent("Remote port forwarding enabled");
d74d141c 2960 }
2961 }
2962 }
2963 }
2964 }
2965
fef97f43 2966 if (!cfg.nopty) {
e5574168 2967 send_packet(SSH1_CMSG_REQUEST_PTY,
32874aea 2968 PKT_STR, cfg.termtype,
2969 PKT_INT, rows, PKT_INT, cols,
2970 PKT_INT, 0, PKT_INT, 0, PKT_CHAR, 0, PKT_END);
2971 ssh_state = SSH_STATE_INTERMED;
2972 do {
2973 crReturnV;
2974 } while (!ispkt);
2975 if (pktin.type != SSH1_SMSG_SUCCESS
2976 && pktin.type != SSH1_SMSG_FAILURE) {
2977 bombout(("Protocol confusion"));
2978 crReturnV;
2979 } else if (pktin.type == SSH1_SMSG_FAILURE) {
2980 c_write_str("Server refused to allocate pty\r\n");
2981 ssh_editing = ssh_echoing = 1;
2982 }
c5e9c988 2983 logevent("Allocated pty");
0965bee0 2984 } else {
32874aea 2985 ssh_editing = ssh_echoing = 1;
374330e2 2986 }
2987
4ba9b64b 2988 if (cfg.compression) {
32874aea 2989 send_packet(SSH1_CMSG_REQUEST_COMPRESSION, PKT_INT, 6, PKT_END);
2990 do {
2991 crReturnV;
2992 } while (!ispkt);
2993 if (pktin.type != SSH1_SMSG_SUCCESS
2994 && pktin.type != SSH1_SMSG_FAILURE) {
2995 bombout(("Protocol confusion"));
2996 crReturnV;
2997 } else if (pktin.type == SSH1_SMSG_FAILURE) {
2998 c_write_str("Server refused to compress\r\n");
2999 }
4ba9b64b 3000 logevent("Started compression");
3001 ssh1_compressing = TRUE;
3002 zlib_compress_init();
3003 zlib_decompress_init();
3004 }
3005
fd5e5847 3006 /*
3007 * Start the shell or command.
3008 *
3009 * Special case: if the first-choice command is an SSH2
3010 * subsystem (hence not usable here) and the second choice
3011 * exists, we fall straight back to that.
3012 */
3013 {
3014 char *cmd = cfg.remote_cmd_ptr;
3015
3016 if (cfg.ssh_subsys && cfg.remote_cmd_ptr2) {
3017 cmd = cfg.remote_cmd_ptr2;
3018 ssh_fallback_cmd = TRUE;
3019 }
3020 if (*cmd)
3021 send_packet(SSH1_CMSG_EXEC_CMD, PKT_STR, cmd, PKT_END);
3022 else
3023 send_packet(SSH1_CMSG_EXEC_SHELL, PKT_END);
3024 logevent("Started session");
3025 }
374330e2 3026
3027 ssh_state = SSH_STATE_SESSION;
3028 if (size_needed)
3029 ssh_size();
3687d221 3030 if (eof_needed)
32874aea 3031 ssh_special(TS_EOF);
374330e2 3032
760e88b2 3033 ldisc_send(NULL, 0, 0); /* cause ldisc to notice changes */
8ccc75b0 3034 ssh_send_ok = 1;
dacbd0e8 3035 ssh_channels = newtree234(ssh_channelcmp);
374330e2 3036 while (1) {
3037 crReturnV;
3038 if (ispkt) {
e5574168 3039 if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
32874aea 3040 pktin.type == SSH1_SMSG_STDERR_DATA) {
fb09bf1c 3041 long len = GET_32BIT(pktin.body);
5471d09a 3042 int bufsize =
3043 from_backend(pktin.type == SSH1_SMSG_STDERR_DATA,
3044 pktin.body + 4, len);
90347b95 3045 if (!ssh1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
5471d09a 3046 ssh1_stdout_throttling = 1;
3047 ssh1_throttle(+1);
3048 }
e5574168 3049 } else if (pktin.type == SSH1_MSG_DISCONNECT) {
32874aea 3050 ssh_state = SSH_STATE_CLOSED;
c5e9c988 3051 logevent("Received disconnect request");
32874aea 3052 crReturnV;
3053 } else if (pktin.type == SSH1_SMSG_X11_OPEN) {
3054 /* Remote side is trying to open a channel to talk to our
3055 * X-Server. Give them back a local channel number. */
3056 struct ssh_channel *c;
9c964e85 3057
3058 logevent("Received X11 connect request");
3059 /* Refuse if X11 forwarding is disabled. */
3060 if (!ssh_X11_fwd_enabled) {
3061 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE,
32874aea 3062 PKT_INT, GET_32BIT(pktin.body), PKT_END);
9c964e85 3063 logevent("Rejected X11 connect request");
3064 } else {
9c964e85 3065 c = smalloc(sizeof(struct ssh_channel));
3066
32874aea 3067 if (x11_init(&c->u.x11.s, cfg.x11_display, c) != NULL) {
3068 logevent("opening X11 forward connection failed");
3069 sfree(c);
3070 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE,
3071 PKT_INT, GET_32BIT(pktin.body),
3072 PKT_END);
9c964e85 3073 } else {
32874aea 3074 logevent
3075 ("opening X11 forward connection succeeded");
3076 c->remoteid = GET_32BIT(pktin.body);
3077 c->localid = alloc_channel_id();
3078 c->closes = 0;
5471d09a 3079 c->v.v1.throttling = 0;
32874aea 3080 c->type = CHAN_X11; /* identify channel type */
3081 add234(ssh_channels, c);
3082 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
3083 PKT_INT, c->remoteid, PKT_INT,
3084 c->localid, PKT_END);
3085 logevent("Opened X11 forward channel");
9c964e85 3086 }
3087 }
32874aea 3088 } else if (pktin.type == SSH1_SMSG_AGENT_OPEN) {
3089 /* Remote side is trying to open a channel to talk to our
3090 * agent. Give them back a local channel number. */
3091 struct ssh_channel *c;
db7d555c 3092
3093 /* Refuse if agent forwarding is disabled. */
3094 if (!ssh_agentfwd_enabled) {
3095 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE,
32874aea 3096 PKT_INT, GET_32BIT(pktin.body), PKT_END);
db7d555c 3097 } else {
dcbde236 3098 c = smalloc(sizeof(struct ssh_channel));
db7d555c 3099 c->remoteid = GET_32BIT(pktin.body);
d2371c81 3100 c->localid = alloc_channel_id();
db7d555c 3101 c->closes = 0;
5471d09a 3102 c->v.v1.throttling = 0;
32874aea 3103 c->type = CHAN_AGENT; /* identify channel type */
db7d555c 3104 c->u.a.lensofar = 0;
3105 add234(ssh_channels, c);
3106 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
3107 PKT_INT, c->remoteid, PKT_INT, c->localid,
3108 PKT_END);
3109 }
d74d141c 3110 } else if (pktin.type == SSH1_MSG_PORT_OPEN) {
3111 /* Remote side is trying to open a channel to talk to a
3112 * forwarded port. Give them back a local channel number. */
3113 struct ssh_channel *c;
3114 struct ssh_rportfwd pf;
3115 int hostsize, port;
3116 char host[256], buf[1024];
3117 char *p, *h, *e;
3118 c = smalloc(sizeof(struct ssh_channel));
3119
3120 hostsize = GET_32BIT(pktin.body+4);
3121 for(h = host, p = pktin.body+8; hostsize != 0; hostsize--) {
3122 if (h+1 < host+sizeof(host))
3123 *h++ = *p;
95bc8819 3124 p++;
d74d141c 3125 }
3126 *h = 0;
3127 port = GET_32BIT(p);
3128
bc240b21 3129 strcpy(pf.dhost, host);
3130 pf.dport = port;
d74d141c 3131
3132 if (find234(ssh_rportfwds, &pf, NULL) == NULL) {
3133 sprintf(buf, "Rejected remote port open request for %s:%d",
3134 host, port);
3135 logevent(buf);
3136 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE,
3137 PKT_INT, GET_32BIT(pktin.body), PKT_END);
3138 } else {
3139 sprintf(buf, "Received remote port open request for %s:%d",
3140 host, port);
3141 logevent(buf);
3142 e = pfd_newconnect(&c->u.pfd.s, host, port, c);
3143 if (e != NULL) {
3144 char buf[256];
3145 sprintf(buf, "Port open failed: %s", e);
3146 logevent(buf);
3147 sfree(c);
3148 send_packet(SSH1_MSG_CHANNEL_OPEN_FAILURE,
3149 PKT_INT, GET_32BIT(pktin.body),
3150 PKT_END);
3151 } else {
3152 c->remoteid = GET_32BIT(pktin.body);
3153 c->localid = alloc_channel_id();
3154 c->closes = 0;
5471d09a 3155 c->v.v1.throttling = 0;
d74d141c 3156 c->type = CHAN_SOCKDATA; /* identify channel type */
3157 add234(ssh_channels, c);
3158 send_packet(SSH1_MSG_CHANNEL_OPEN_CONFIRMATION,
3159 PKT_INT, c->remoteid, PKT_INT,
3160 c->localid, PKT_END);
3161 logevent("Forwarded port opened successfully");
3162 }
3163 }
3164
3165 } else if (pktin.type == SSH1_MSG_CHANNEL_OPEN_CONFIRMATION) {
bc240b21 3166 unsigned int remoteid = GET_32BIT(pktin.body);
3167 unsigned int localid = GET_32BIT(pktin.body+4);
3168 struct ssh_channel *c;
3169
3170 c = find234(ssh_channels, &remoteid, ssh_channelfind);
3171 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
3172 c->remoteid = localid;
3173 c->type = CHAN_SOCKDATA;
7781f316 3174 c->v.v1.throttling = 0;
bc240b21 3175 pfd_confirm(c->u.pfd.s);
3176 }
d74d141c 3177
4ed34d25 3178 if (c && c->closes) {
3179 /*
3180 * We have a pending close on this channel,
3181 * which we decided on before the server acked
3182 * the channel open. So now we know the
3183 * remoteid, we can close it again.
3184 */
3185 send_packet(SSH1_MSG_CHANNEL_CLOSE, PKT_INT, c->remoteid,
3186 PKT_END);
3187 }
3188
724cface 3189 } else if (pktin.type == SSH1_MSG_CHANNEL_OPEN_FAILURE) {
3190 unsigned int remoteid = GET_32BIT(pktin.body);
3191 unsigned int localid = GET_32BIT(pktin.body+4);
3192 struct ssh_channel *c;
3193
3194 c = find234(ssh_channels, &remoteid, ssh_channelfind);
3195 if (c && c->type == CHAN_SOCKDATA_DORMANT) {
3196 logevent("Forwarded connection refused by server");
3197 pfd_close(c->u.pfd.s);
3198 del234(ssh_channels, c);
3199 sfree(c);
3200 }
3201
db7d555c 3202 } else if (pktin.type == SSH1_MSG_CHANNEL_CLOSE ||
3203 pktin.type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) {
32874aea 3204 /* Remote side closes a channel. */
3205 unsigned i = GET_32BIT(pktin.body);
3206 struct ssh_channel *c;
3207 c = find234(ssh_channels, &i, ssh_channelfind);
3208 if (c) {
3209 int closetype;
3210 closetype =
3211 (pktin.type == SSH1_MSG_CHANNEL_CLOSE ? 1 : 2);
3212 if (!(c->closes & closetype))
3213 send_packet(pktin.type, PKT_INT, c->remoteid,
3214 PKT_END);
783415f8 3215 if ((c->closes == 0) && (c->type == CHAN_X11)) {
d74d141c 3216 logevent("Forwarded X11 connection terminated");
9c964e85 3217 assert(c->u.x11.s != NULL);
3218 x11_close(c->u.x11.s);
3219 c->u.x11.s = NULL;
3220 }
d74d141c 3221 if ((c->closes == 0) && (c->type == CHAN_SOCKDATA)) {
3222 logevent("Forwarded port closed");
3223 assert(c->u.pfd.s != NULL);
3224 pfd_close(c->u.pfd.s);
3225 c->u.pfd.s = NULL;
3226 }
32874aea 3227 c->closes |= closetype;
3228 if (c->closes == 3) {
3229 del234(ssh_channels, c);
3230 sfree(c);
3231 }
3232 }
3233 } else if (pktin.type == SSH1_MSG_CHANNEL_DATA) {
3234 /* Data sent down one of our channels. */
3235 int i = GET_32BIT(pktin.body);
3236 int len = GET_32BIT(pktin.body + 4);
3237 unsigned char *p = pktin.body + 8;
3238 struct ssh_channel *c;
3239 c = find234(ssh_channels, &i, ssh_channelfind);
3240 if (c) {
5471d09a 3241 int bufsize;
32874aea 3242 switch (c->type) {
3243 case CHAN_X11:
5471d09a 3244 bufsize = x11_send(c->u.x11.s, p, len);
9c964e85 3245 break;
d74d141c 3246 case CHAN_SOCKDATA:
5471d09a 3247 bufsize = pfd_send(c->u.pfd.s, p, len);
bc240b21 3248 break;
32874aea 3249 case CHAN_AGENT:
3250 /* Data for an agent message. Buffer it. */
3251 while (len > 0) {
3252 if (c->u.a.lensofar < 4) {
3253 int l = min(4 - c->u.a.lensofar, len);
3254 memcpy(c->u.a.msglen + c->u.a.lensofar, p,
3255 l);
3256 p += l;
3257 len -= l;
3258 c->u.a.lensofar += l;
3259 }
3260 if (c->u.a.lensofar == 4) {
3261 c->u.a.totallen =
3262 4 + GET_32BIT(c->u.a.msglen);
3263 c->u.a.message = smalloc(c->u.a.totallen);
3264 memcpy(c->u.a.message, c->u.a.msglen, 4);
3265 }
3266 if (c->u.a.lensofar >= 4 && len > 0) {
3267 int l =
3268 min(c->u.a.totallen - c->u.a.lensofar,
3269 len);
3270 memcpy(c->u.a.message + c->u.a.lensofar, p,
3271 l);
3272 p += l;
3273 len -= l;
3274 c->u.a.lensofar += l;
3275 }
3276 if (c->u.a.lensofar == c->u.a.totallen) {
3277 void *reply, *sentreply;
3278 int replylen;
3279 agent_query(c->u.a.message,
3280 c->u.a.totallen, &reply,
3281 &replylen);
3282 if (reply)
3283 sentreply = reply;
3284 else {
3285 /* Fake SSH_AGENT_FAILURE. */
3286 sentreply = "\0\0\0\1\5";
3287 replylen = 5;
3288 }
3289 send_packet(SSH1_MSG_CHANNEL_DATA,
3290 PKT_INT, c->remoteid,
3291 PKT_INT, replylen,
3292 PKT_DATA, sentreply, replylen,
3293 PKT_END);
3294 if (reply)
3295 sfree(reply);
3296 sfree(c->u.a.message);
3297 c->u.a.lensofar = 0;
3298 }
3299 }
5471d09a 3300 bufsize = 0; /* agent channels never back up */
32874aea 3301 break;
3302 }
90347b95 3303 if (!c->v.v1.throttling && bufsize > SSH1_BUFFER_LIMIT) {
5471d09a 3304 c->v.v1.throttling = 1;
3305 ssh1_throttle(+1);
3306 }
32874aea 3307 }
e5574168 3308 } else if (pktin.type == SSH1_SMSG_SUCCESS) {
972a41c8 3309 /* may be from EXEC_SHELL on some servers */
e5574168 3310 } else if (pktin.type == SSH1_SMSG_FAILURE) {
972a41c8 3311 /* may be from EXEC_SHELL on some servers
374330e2 3312 * if no pty is available or in other odd cases. Ignore */
e5574168 3313 } else if (pktin.type == SSH1_SMSG_EXIT_STATUS) {
d8d6c7e5 3314 char buf[100];
3315 ssh_exitcode = GET_32BIT(pktin.body);
3316 sprintf(buf, "Server sent command exit status %d",
3317 ssh_exitcode);
3318 logevent(buf);
e5574168 3319 send_packet(SSH1_CMSG_EXIT_CONFIRMATION, PKT_END);
4252c9cc 3320 /*
3321 * In case `helpful' firewalls or proxies tack
3322 * extra human-readable text on the end of the
3323 * session which we might mistake for another
3324 * encrypted packet, we close the session once
3325 * we've sent EXIT_CONFIRMATION.
3326 */
3327 ssh_state = SSH_STATE_CLOSED;
3328 crReturnV;
374330e2 3329 } else {
8d5de777 3330 bombout(("Strange packet received: type %d", pktin.type));
32874aea 3331 crReturnV;
374330e2 3332 }
3333 } else {
8df7a775 3334 while (inlen > 0) {
3335 int len = min(inlen, 512);
3336 send_packet(SSH1_CMSG_STDIN_DATA,
3337 PKT_INT, len, PKT_DATA, in, len, PKT_END);
3338 in += len;
3339 inlen -= len;
3340 }
374330e2 3341 }
3342 }
3343
3344 crFinishV;
3345}
3346
3347/*
e5574168 3348 * Utility routine for decoding comma-separated strings in KEXINIT.
3349 */
32874aea 3350static int in_commasep_string(char *needle, char *haystack, int haylen)
3351{
e5574168 3352 int needlen = strlen(needle);
3353 while (1) {
32874aea 3354 /*
3355 * Is it at the start of the string?
3356 */
3357 if (haylen >= needlen && /* haystack is long enough */
3358 !memcmp(needle, haystack, needlen) && /* initial match */
3359 (haylen == needlen || haystack[needlen] == ',')
3360 /* either , or EOS follows */
3361 )
3362 return 1;
3363 /*
3364 * If not, search for the next comma and resume after that.
3365 * If no comma found, terminate.
3366 */
3367 while (haylen > 0 && *haystack != ',')
3368 haylen--, haystack++;
3369 if (haylen == 0)
3370 return 0;
3371 haylen--, haystack++; /* skip over comma itself */
e5574168 3372 }
3373}
3374
3375/*
d39f364a 3376 * SSH2 key creation method.
3377 */
32874aea 3378static void ssh2_mkkey(Bignum K, char *H, char *sessid, char chr,
3379 char *keyspace)
3380{
d39f364a 3381 SHA_State s;
3382 /* First 20 bytes. */
3383 SHA_Init(&s);
3384 sha_mpint(&s, K);
3385 SHA_Bytes(&s, H, 20);
3386 SHA_Bytes(&s, &chr, 1);
5e0d7cb8 3387 SHA_Bytes(&s, sessid, 20);
d39f364a 3388 SHA_Final(&s, keyspace);
3389 /* Next 20 bytes. */
3390 SHA_Init(&s);
3391 sha_mpint(&s, K);
3392 SHA_Bytes(&s, H, 20);
3393 SHA_Bytes(&s, keyspace, 20);
32874aea 3394 SHA_Final(&s, keyspace + 20);
d39f364a 3395}
3396
3397/*
7cca0d81 3398 * Handle the SSH2 transport layer.
e5574168 3399 */
7cca0d81 3400static int do_ssh2_transport(unsigned char *in, int inlen, int ispkt)
e5574168 3401{
ca20bfcf 3402 static int i, j, len, nbits, pbits, warn;
e5574168 3403 static char *str;
a92dd380 3404 static Bignum p, g, e, f, K;
3405 static int kex_init_value, kex_reply_value;
7591b9ff 3406 static const struct ssh_mac **maclist;
8b2715b2 3407 static int nmacs;
0a3f1d48 3408 static const struct ssh2_cipher *cscipher_tobe = NULL;
3409 static const struct ssh2_cipher *sccipher_tobe = NULL;
57476f6b 3410 static const struct ssh_mac *csmac_tobe = NULL;
3411 static const struct ssh_mac *scmac_tobe = NULL;
3412 static const struct ssh_compress *cscomp_tobe = NULL;
3413 static const struct ssh_compress *sccomp_tobe = NULL;
d5859615 3414 static char *hostkeydata, *sigdata, *keystr, *fingerprint;
e5574168 3415 static int hostkeylen, siglen;
e055a386 3416 static void *hkey; /* actual host key */
e5574168 3417 static unsigned char exchange_hash[20];
d39f364a 3418 static unsigned char keyspace[40];
ca20bfcf 3419 static int n_preferred_ciphers;
3420 static const struct ssh2_ciphers *preferred_ciphers[CIPHER_MAX];
4ba9b64b 3421 static const struct ssh_compress *preferred_comp;
087abe1a 3422 static int cipherstr_started;
0db56f73 3423 static int first_kex;
e5574168 3424
3425 crBegin;
7cca0d81 3426 random_init();
0db56f73 3427 first_kex = 1;
e5574168 3428
5e8358ad 3429 /*
ca20bfcf 3430 * Set up the preferred ciphers. (NULL => warn below here)
5e8358ad 3431 */
ca20bfcf 3432 n_preferred_ciphers = 0;
3433 for (i = 0; i < CIPHER_MAX; i++) {
3434 switch (cfg.ssh_cipherlist[i]) {
3435 case CIPHER_BLOWFISH:
3436 preferred_ciphers[n_preferred_ciphers] = &ssh2_blowfish;
3437 n_preferred_ciphers++;
3438 break;
3439 case CIPHER_DES:
087abe1a 3440 if (cfg.ssh2_des_cbc) {
3441 preferred_ciphers[n_preferred_ciphers] = &ssh2_des;
3442 n_preferred_ciphers++;
3443 }
ca20bfcf 3444 break;
3445 case CIPHER_3DES:
3446 preferred_ciphers[n_preferred_ciphers] = &ssh2_3des;
3447 n_preferred_ciphers++;
3448 break;
3449 case CIPHER_AES:
3450 preferred_ciphers[n_preferred_ciphers] = &ssh2_aes;
3451 n_preferred_ciphers++;
3452 break;
3453 case CIPHER_WARN:
3454 /* Flag for later. Don't bother if it's the last in
3455 * the list. */
3456 if (i < CIPHER_MAX - 1) {
3457 preferred_ciphers[n_preferred_ciphers] = NULL;
3458 n_preferred_ciphers++;
3459 }
3460 break;
3461 }
5e8358ad 3462 }
ca20bfcf 3463
3464 /*
3465 * Set up preferred compression.
3466 */
4ba9b64b 3467 if (cfg.compression)
3468 preferred_comp = &ssh_zlib;
3469 else
3470 preferred_comp = &ssh_comp_none;
5e8358ad 3471
7591b9ff 3472 /*
3473 * Be prepared to work around the buggy MAC problem.
3474 */
7d503c31 3475 if (cfg.buggymac || (ssh_remote_bugs & BUG_SSH2_HMAC))
32874aea 3476 maclist = buggymacs, nmacs = lenof(buggymacs);
7591b9ff 3477 else
32874aea 3478 maclist = macs, nmacs = lenof(macs);
7591b9ff 3479
32874aea 3480 begin_key_exchange:
e5574168 3481 /*
3482 * Construct and send our key exchange packet.
3483 */
3484 ssh2_pkt_init(SSH2_MSG_KEXINIT);
3485 for (i = 0; i < 16; i++)
32874aea 3486 ssh2_pkt_addbyte((unsigned char) random_byte());
e5574168 3487 /* List key exchange algorithms. */
3488 ssh2_pkt_addstring_start();
3489 for (i = 0; i < lenof(kex_algs); i++) {
32874aea 3490 ssh2_pkt_addstring_str(kex_algs[i]->name);
3491 if (i < lenof(kex_algs) - 1)
3492 ssh2_pkt_addstring_str(",");
e5574168 3493 }
3494 /* List server host key algorithms. */
3495 ssh2_pkt_addstring_start();
3496 for (i = 0; i < lenof(hostkey_algs); i++) {
32874aea 3497 ssh2_pkt_addstring_str(hostkey_algs[i]->name);
3498 if (i < lenof(hostkey_algs) - 1)
3499 ssh2_pkt_addstring_str(",");
e5574168 3500 }
3501 /* List client->server encryption algorithms. */
3502 ssh2_pkt_addstring_start();
087abe1a 3503 cipherstr_started = 0;
ca20bfcf 3504 for (i = 0; i < n_preferred_ciphers; i++) {
3505 const struct ssh2_ciphers *c = preferred_ciphers[i];
3506 if (!c) continue; /* warning flag */
32874aea 3507 for (j = 0; j < c->nciphers; j++) {
087abe1a 3508 if (cipherstr_started)
32874aea 3509 ssh2_pkt_addstring_str(",");
087abe1a 3510 ssh2_pkt_addstring_str(c->list[j]->name);
3511 cipherstr_started = 1;
32874aea 3512 }
e5574168 3513 }
3514 /* List server->client encryption algorithms. */
3515 ssh2_pkt_addstring_start();
087abe1a 3516 cipherstr_started = 0;
ca20bfcf 3517 for (i = 0; i < n_preferred_ciphers; i++) {
3518 const struct ssh2_ciphers *c = preferred_ciphers[i];
3519 if (!c) continue; /* warning flag */
32874aea 3520 for (j = 0; j < c->nciphers; j++) {
087abe1a 3521 if (cipherstr_started)
32874aea 3522 ssh2_pkt_addstring_str(",");
087abe1a 3523 ssh2_pkt_addstring_str(c->list[j]->name);
3524 cipherstr_started = 1;
32874aea 3525 }
e5574168 3526 }
3527 /* List client->server MAC algorithms. */
3528 ssh2_pkt_addstring_start();
8b2715b2 3529 for (i = 0; i < nmacs; i++) {
32874aea 3530 ssh2_pkt_addstring_str(maclist[i]->name);
3531 if (i < nmacs - 1)
3532 ssh2_pkt_addstring_str(",");
e5574168 3533 }
3534 /* List server->client MAC algorithms. */
3535 ssh2_pkt_addstring_start();
8b2715b2 3536 for (i = 0; i < nmacs; i++) {
32874aea 3537 ssh2_pkt_addstring_str(maclist[i]->name);
3538 if (i < nmacs - 1)
3539 ssh2_pkt_addstring_str(",");
e5574168 3540 }
3541 /* List client->server compression algorithms. */
3542 ssh2_pkt_addstring_start();
32874aea 3543 for (i = 0; i < lenof(compressions) + 1; i++) {
3544 const struct ssh_compress *c =
3545 i == 0 ? preferred_comp : compressions[i - 1];
3546 ssh2_pkt_addstring_str(c->name);
3547 if (i < lenof(compressions))
3548 ssh2_pkt_addstring_str(",");
e5574168 3549 }
3550 /* List server->client compression algorithms. */
3551 ssh2_pkt_addstring_start();
32874aea 3552 for (i = 0; i < lenof(compressions) + 1; i++) {
3553 const struct ssh_compress *c =
3554 i == 0 ? preferred_comp : compressions[i - 1];
3555 ssh2_pkt_addstring_str(c->name);
3556 if (i < lenof(compressions))
3557 ssh2_pkt_addstring_str(",");
e5574168 3558 }
3559 /* List client->server languages. Empty list. */
3560 ssh2_pkt_addstring_start();
3561 /* List server->client languages. Empty list. */
3562 ssh2_pkt_addstring_start();
3563 /* First KEX packet does _not_ follow, because we're not that brave. */
3564 ssh2_pkt_addbool(FALSE);
3565 /* Reserved. */
3566 ssh2_pkt_adduint32(0);
0db56f73 3567
3568 exhash = exhashbase;
32874aea 3569 sha_string(&exhash, pktout.data + 5, pktout.length - 5);
0db56f73 3570
e5574168 3571 ssh2_pkt_send();
3572
32874aea 3573 if (!ispkt)
3574 crWaitUntil(ispkt);
3575 sha_string(&exhash, pktin.data + 5, pktin.length - 5);
e5574168 3576
3577 /*
3578 * Now examine the other side's KEXINIT to see what we're up
3579 * to.
3580 */
7cca0d81 3581 if (pktin.type != SSH2_MSG_KEXINIT) {
32874aea 3582 bombout(("expected key exchange packet from server"));
3583 crReturn(0);
7cca0d81 3584 }
32874aea 3585 kex = NULL;
3586 hostkey = NULL;
3587 cscipher_tobe = NULL;
3588 sccipher_tobe = NULL;
3589 csmac_tobe = NULL;
3590 scmac_tobe = NULL;
3591 cscomp_tobe = NULL;
3592 sccomp_tobe = NULL;
3593 pktin.savedpos += 16; /* skip garbage cookie */
e5574168 3594 ssh2_pkt_getstring(&str, &len); /* key exchange algorithms */
3595 for (i = 0; i < lenof(kex_algs); i++) {
32874aea 3596 if (in_commasep_string(kex_algs[i]->name, str, len)) {
3597 kex = kex_algs[i];
3598 break;
3599 }
e5574168 3600 }
3601 ssh2_pkt_getstring(&str, &len); /* host key algorithms */
3602 for (i = 0; i < lenof(hostkey_algs); i++) {
32874aea 3603 if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
3604 hostkey = hostkey_algs[i];
3605 break;
3606 }
e5574168 3607 }
3608 ssh2_pkt_getstring(&str, &len); /* client->server cipher */
ca20bfcf 3609 warn = 0;
3610 for (i = 0; i < n_preferred_ciphers; i++) {
3611 const struct ssh2_ciphers *c = preferred_ciphers[i];
3612 if (!c) {
3613 warn = 1;
3614 } else {
3615 for (j = 0; j < c->nciphers; j++) {
3616 if (in_commasep_string(c->list[j]->name, str, len)) {
3617 cscipher_tobe = c->list[j];
3618 break;
3619 }
32874aea 3620 }
3621 }
ca20bfcf 3622 if (cscipher_tobe) {
3623 if (warn)
3624 askcipher(cscipher_tobe->name, 1);
32874aea 3625 break;
ca20bfcf 3626 }
e5574168 3627 }
0ef8f407 3628 if (!cscipher_tobe) {
3629 bombout(("Couldn't agree a client-to-server cipher (available: %s)", str));
3630 crReturn(0);
3631 }
3632
e5574168 3633 ssh2_pkt_getstring(&str, &len); /* server->client cipher */
ca20bfcf 3634 warn = 0;
3635 for (i = 0; i < n_preferred_ciphers; i++) {
3636 const struct ssh2_ciphers *c = preferred_ciphers[i];
3637 if (!c) {
3638 warn = 1;
3639 } else {
3640 for (j = 0; j < c->nciphers; j++) {
3641 if (in_commasep_string(c->list[j]->name, str, len)) {
3642 sccipher_tobe = c->list[j];
3643 break;
3644 }
32874aea 3645 }
3646 }
ca20bfcf 3647 if (sccipher_tobe) {
3648 if (warn)
3649 askcipher(sccipher_tobe->name, 2);
32874aea 3650 break;
ca20bfcf 3651 }
e5574168 3652 }
0ef8f407 3653 if (!sccipher_tobe) {
3654 bombout(("Couldn't agree a server-to-client cipher (available: %s)", str));
3655 crReturn(0);
3656 }
3657
e5574168 3658 ssh2_pkt_getstring(&str, &len); /* client->server mac */
8b2715b2 3659 for (i = 0; i < nmacs; i++) {
32874aea 3660 if (in_commasep_string(maclist[i]->name, str, len)) {
3661 csmac_tobe = maclist[i];
3662 break;
3663 }
e5574168 3664 }
3665 ssh2_pkt_getstring(&str, &len); /* server->client mac */
8b2715b2 3666 for (i = 0; i < nmacs; i++) {
32874aea 3667 if (in_commasep_string(maclist[i]->name, str, len)) {
3668 scmac_tobe = maclist[i];
3669 break;
3670 }
e5574168 3671 }
3672 ssh2_pkt_getstring(&str, &len); /* client->server compression */
32874aea 3673 for (i = 0; i < lenof(compressions) + 1; i++) {
3674 const struct ssh_compress *c =
3675 i == 0 ? preferred_comp : compressions[i - 1];
3676 if (in_commasep_string(c->name, str, len)) {
3677 cscomp_tobe = c;
3678 break;
3679 }
e5574168 3680 }
3681 ssh2_pkt_getstring(&str, &len); /* server->client compression */
32874aea 3682 for (i = 0; i < lenof(compressions) + 1; i++) {
3683 const struct ssh_compress *c =
3684 i == 0 ? preferred_comp : compressions[i - 1];
3685 if (in_commasep_string(c->name, str, len)) {
3686 sccomp_tobe = c;
3687 break;
3688 }
e5574168 3689 }
e5574168 3690
3691 /*
7bd5a860 3692 * Work out the number of bits of key we will need from the key
3693 * exchange. We start with the maximum key length of either
3694 * cipher...
3695 */
3696 {
32874aea 3697 int csbits, scbits;
7bd5a860 3698
3699 csbits = cscipher_tobe->keylen;
3700 scbits = sccipher_tobe->keylen;
3701 nbits = (csbits > scbits ? csbits : scbits);
3702 }
3703 /* The keys only have 160-bit entropy, since they're based on
3704 * a SHA-1 hash. So cap the key size at 160 bits. */
32874aea 3705 if (nbits > 160)
3706 nbits = 160;
7bd5a860 3707
3708 /*
a92dd380 3709 * If we're doing Diffie-Hellman group exchange, start by
3710 * requesting a group.
e5574168 3711 */
a92dd380 3712 if (kex == &ssh_diffiehellman_gex) {
32874aea 3713 logevent("Doing Diffie-Hellman group exchange");
00db133f 3714 ssh_pkt_ctx |= SSH2_PKTCTX_DHGEX;
32874aea 3715 /*
3716 * Work out how big a DH group we will need to allow that
3717 * much data.
7bd5a860 3718 */
32874aea 3719 pbits = 512 << ((nbits - 1) / 64);
3720 ssh2_pkt_init(SSH2_MSG_KEX_DH_GEX_REQUEST);
3721 ssh2_pkt_adduint32(pbits);
3722 ssh2_pkt_send();
3723
3724 crWaitUntil(ispkt);
3725 if (pktin.type != SSH2_MSG_KEX_DH_GEX_GROUP) {
3726 bombout(("expected key exchange group packet from server"));
3727 crReturn(0);
3728 }
3729 p = ssh2_pkt_getmp();
3730 g = ssh2_pkt_getmp();
3731 dh_setup_group(p, g);
3732 kex_init_value = SSH2_MSG_KEX_DH_GEX_INIT;
3733 kex_reply_value = SSH2_MSG_KEX_DH_GEX_REPLY;
a92dd380 3734 } else {
00db133f 3735 ssh_pkt_ctx |= SSH2_PKTCTX_DHGROUP1;
32874aea 3736 dh_setup_group1();
3737 kex_init_value = SSH2_MSG_KEXDH_INIT;
3738 kex_reply_value = SSH2_MSG_KEXDH_REPLY;
8d5de777 3739 }
e5574168 3740
a92dd380 3741 logevent("Doing Diffie-Hellman key exchange");
e5574168 3742 /*
a92dd380 3743 * Now generate and send e for Diffie-Hellman.
e5574168 3744 */
32874aea 3745 e = dh_create_e(nbits * 2);
a92dd380 3746 ssh2_pkt_init(kex_init_value);
e5574168 3747 ssh2_pkt_addmp(e);
3748 ssh2_pkt_send();
3749
3750 crWaitUntil(ispkt);
a92dd380 3751 if (pktin.type != kex_reply_value) {
32874aea 3752 bombout(("expected key exchange reply packet from server"));
3753 crReturn(0);
7cca0d81 3754 }
e5574168 3755 ssh2_pkt_getstring(&hostkeydata, &hostkeylen);
3756 f = ssh2_pkt_getmp();
e5574168 3757 ssh2_pkt_getstring(&sigdata, &siglen);
3758
3759 K = dh_find_K(f);
e5574168 3760
3761 sha_string(&exhash, hostkeydata, hostkeylen);
a92dd380 3762 if (kex == &ssh_diffiehellman_gex) {
32874aea 3763 sha_uint32(&exhash, pbits);
3764 sha_mpint(&exhash, p);
3765 sha_mpint(&exhash, g);
a92dd380 3766 }
e5574168 3767 sha_mpint(&exhash, e);
3768 sha_mpint(&exhash, f);
3769 sha_mpint(&exhash, K);
3770 SHA_Final(&exhash, exchange_hash);
3771
3709bfe9 3772 dh_cleanup();
3773
7cca0d81 3774#if 0
765c4200 3775 debug(("Exchange hash is:\n"));
3776 dmemdump(exchange_hash, 20);
7cca0d81 3777#endif
3778
e055a386 3779 hkey = hostkey->newkey(hostkeydata, hostkeylen);
f7259d10 3780 if (!hkey ||
3781 !hostkey->verifysig(hkey, sigdata, siglen, exchange_hash, 20)) {
3782 bombout(("Server's host key did not match the signature supplied"));
32874aea 3783 crReturn(0);
8d5de777 3784 }
e5574168 3785
3786 /*
7cca0d81 3787 * Authenticate remote host: verify host key. (We've already
3788 * checked the signature of the exchange hash.)
e5574168 3789 */
e055a386 3790 keystr = hostkey->fmtkey(hkey);
3791 fingerprint = hostkey->fingerprint(hkey);
d4857987 3792 verify_ssh_host_key(savedhost, savedport, hostkey->keytype,
32874aea 3793 keystr, fingerprint);
3794 if (first_kex) { /* don't bother logging this in rekeys */
5e0d7cb8 3795 logevent("Host key fingerprint is:");
3796 logevent(fingerprint);
3797 }
dcbde236 3798 sfree(fingerprint);
3799 sfree(keystr);
e055a386 3800 hostkey->freekey(hkey);
d39f364a 3801
3802 /*
7cca0d81 3803 * Send SSH2_MSG_NEWKEYS.
d39f364a 3804 */
3805 ssh2_pkt_init(SSH2_MSG_NEWKEYS);
3806 ssh2_pkt_send();
d39f364a 3807
3808 /*
8406eaf9 3809 * Expect SSH2_MSG_NEWKEYS from server.
3810 */
3811 crWaitUntil(ispkt);
3812 if (pktin.type != SSH2_MSG_NEWKEYS) {
3813 bombout(("expected new-keys packet from server"));
3814 crReturn(0);
3815 }
3816
3817 /*
d39f364a 3818 * Create and initialise session keys.
3819 */
3820 cscipher = cscipher_tobe;
3821 sccipher = sccipher_tobe;
3822 csmac = csmac_tobe;
3823 scmac = scmac_tobe;
3824 cscomp = cscomp_tobe;
3825 sccomp = sccomp_tobe;
4ba9b64b 3826 cscomp->compress_init();
3827 sccomp->decompress_init();
d39f364a 3828 /*
5e0d7cb8 3829 * Set IVs after keys. Here we use the exchange hash from the
3830 * _first_ key exchange.
d39f364a 3831 */
5e0d7cb8 3832 if (first_kex)
65a22376 3833 memcpy(ssh2_session_id, exchange_hash, sizeof(exchange_hash));
3834 ssh2_mkkey(K, exchange_hash, ssh2_session_id, 'C', keyspace);
5e0d7cb8 3835 cscipher->setcskey(keyspace);
65a22376 3836 ssh2_mkkey(K, exchange_hash, ssh2_session_id, 'D', keyspace);
5e0d7cb8 3837 sccipher->setsckey(keyspace);
65a22376 3838 ssh2_mkkey(K, exchange_hash, ssh2_session_id, 'A', keyspace);
5e0d7cb8 3839 cscipher->setcsiv(keyspace);
65a22376 3840 ssh2_mkkey(K, exchange_hash, ssh2_session_id, 'B', keyspace);
5e0d7cb8 3841 sccipher->setsciv(keyspace);
65a22376 3842 ssh2_mkkey(K, exchange_hash, ssh2_session_id, 'E', keyspace);
5e0d7cb8 3843 csmac->setcskey(keyspace);
65a22376 3844 ssh2_mkkey(K, exchange_hash, ssh2_session_id, 'F', keyspace);
5e0d7cb8 3845 scmac->setsckey(keyspace);
d39f364a 3846
033b4cef 3847 /*
0db56f73 3848 * If this is the first key exchange phase, we must pass the
3849 * SSH2_MSG_NEWKEYS packet to the next layer, not because it
3850 * wants to see it but because it will need time to initialise
3851 * itself before it sees an actual packet. In subsequent key
3852 * exchange phases, we don't pass SSH2_MSG_NEWKEYS on, because
3853 * it would only confuse the layer above.
3854 */
3855 if (!first_kex) {
32874aea 3856 crReturn(0);
0db56f73 3857 }
3858 first_kex = 0;
3859
3860 /*
7cca0d81 3861 * Now we're encrypting. Begin returning 1 to the protocol main
3862 * function so that other things can run on top of the
3863 * transport. If we ever see a KEXINIT, we must go back to the
3864 * start.
033b4cef 3865 */
e96adf72 3866 while (!(ispkt && pktin.type == SSH2_MSG_KEXINIT)) {
32874aea 3867 crReturn(1);
e96adf72 3868 }
5e0d7cb8 3869 logevent("Server initiated key re-exchange");
7cca0d81 3870 goto begin_key_exchange;
e5574168 3871
3872 crFinish(1);
3873}
3874
7cca0d81 3875/*
783415f8 3876 * Add data to an SSH2 channel output buffer.
3877 */
32874aea 3878static void ssh2_add_channel_data(struct ssh_channel *c, char *buf,
3879 int len)
3880{
5471d09a 3881 bufchain_add(&c->v.v2.outbuffer, buf, len);
783415f8 3882}
3883
3884/*
3885 * Attempt to send data on an SSH2 channel.
3886 */
5471d09a 3887static int ssh2_try_send(struct ssh_channel *c)
32874aea 3888{
5471d09a 3889 while (c->v.v2.remwindow > 0 && bufchain_size(&c->v.v2.outbuffer) > 0) {
3890 int len;
3891 void *data;
3892 bufchain_prefix(&c->v.v2.outbuffer, &data, &len);
3893 if ((unsigned)len > c->v.v2.remwindow)
3894 len = c->v.v2.remwindow;
3895 if ((unsigned)len > c->v.v2.remmaxpkt)
3896 len = c->v.v2.remmaxpkt;
32874aea 3897 ssh2_pkt_init(SSH2_MSG_CHANNEL_DATA);
3898 ssh2_pkt_adduint32(c->remoteid);
3899 ssh2_pkt_addstring_start();
5471d09a 3900 ssh2_pkt_addstring_data(data, len);
32874aea 3901 ssh2_pkt_send();
5471d09a 3902 bufchain_consume(&c->v.v2.outbuffer, len);
3903 c->v.v2.remwindow -= len;
3904 }
3905
3906 /*
3907 * After having sent as much data as we can, return the amount
3908 * still buffered.
3909 */
3910 return bufchain_size(&c->v.v2.outbuffer);
3911}
3912
3913/*
3914 * Potentially enlarge the window on an SSH2 channel.
3915 */
3916static void ssh2_set_window(struct ssh_channel *c, unsigned newwin)
3917{
6b69f42e 3918 /*
3919 * Never send WINDOW_ADJUST for a channel that the remote side
3920 * already thinks it's closed; there's no point, since it won't
3921 * be sending any more data anyway.
3922 */
3923 if (c->closes != 0)
3924 return;
3925
5471d09a 3926 if (newwin > c->v.v2.locwindow) {
3927 ssh2_pkt_init(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
3928 ssh2_pkt_adduint32(c->remoteid);
3929 ssh2_pkt_adduint32(newwin - c->v.v2.locwindow);
3930 ssh2_pkt_send();
3931 c->v.v2.locwindow = newwin;
783415f8 3932 }
3933}
3934
3935/*
7cca0d81 3936 * Handle the SSH2 userauth and connection layers.
3937 */
3938static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
3939{
65a22376 3940 static enum {
32874aea 3941 AUTH_INVALID, AUTH_PUBLICKEY_AGENT, AUTH_PUBLICKEY_FILE,
761187b6 3942 AUTH_PASSWORD,
3943 AUTH_KEYBOARD_INTERACTIVE
65a22376 3944 } method;
1408a877 3945 static enum {
32874aea 3946 AUTH_TYPE_NONE,
3947 AUTH_TYPE_PUBLICKEY,
3948 AUTH_TYPE_PUBLICKEY_OFFER_LOUD,
3949 AUTH_TYPE_PUBLICKEY_OFFER_QUIET,
761187b6 3950 AUTH_TYPE_PASSWORD,
4bdf7c46 3951 AUTH_TYPE_KEYBOARD_INTERACTIVE,
3952 AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET
1408a877 3953 } type;
761187b6 3954 static int gotit, need_pw, can_pubkey, can_passwd, can_keyb_inter;
3955 static int tried_pubkey_config, tried_agent, tried_keyb_inter;
b3186d64 3956 static int kbd_inter_running;
1408a877 3957 static int we_are_in;
761187b6 3958 static int num_prompts, echo;
65a22376 3959 static char username[100];
7e9b7f4b 3960 static int got_username;
65a22376 3961 static char pwprompt[200];
3962 static char password[100];
396778f1 3963 static void *publickey_blob;
3964 static int publickey_bloblen;
7cca0d81 3965
e5574168 3966 crBegin;
3967
7cca0d81 3968 /*
3969 * Request userauth protocol, and await a response to it.
3970 */
3971 ssh2_pkt_init(SSH2_MSG_SERVICE_REQUEST);
3972 ssh2_pkt_addstring("ssh-userauth");
3973 ssh2_pkt_send();
3974 crWaitUntilV(ispkt);
8d5de777 3975 if (pktin.type != SSH2_MSG_SERVICE_ACCEPT) {
32874aea 3976 bombout(("Server refused user authentication protocol"));
3977 crReturnV;
8d5de777 3978 }
7cca0d81 3979
3980 /*
1408a877 3981 * We repeat this whole loop, including the username prompt,
3982 * until we manage a successful authentication. If the user
3983 * types the wrong _password_, they are sent back to the
3984 * beginning to try another username. (If they specify a
3985 * username in the config, they are never asked, even if they
3986 * do give a wrong password.)
3987 *
3988 * I think this best serves the needs of
3989 *
3990 * - the people who have no configuration, no keys, and just
3991 * want to try repeated (username,password) pairs until they
3992 * type both correctly
3993 *
3994 * - people who have keys and configuration but occasionally
3995 * need to fall back to passwords
3996 *
3997 * - people with a key held in Pageant, who might not have
3998 * logged in to a particular machine before; so they want to
3999 * type a username, and then _either_ their key will be
4000 * accepted, _or_ they will type a password. If they mistype
4001 * the username they will want to be able to get back and
4002 * retype it!
7cca0d81 4003 */
5bb641e1 4004 username[0] = '\0';
7e9b7f4b 4005 got_username = FALSE;
1408a877 4006 do {
4007 static int pos;
7cca0d81 4008 static char c;
e5574168 4009
1408a877 4010 /*
4011 * Get a username.
4012 */
4013 pos = 0;
7e9b7f4b 4014 if (got_username && !cfg.change_username) {
5bb641e1 4015 /*
4016 * We got a username last time round this loop, and
4017 * with change_username turned off we don't try to get
4018 * it again.
4019 */
4020 } else if ((flags & FLAG_INTERACTIVE) && !*cfg.username) {
32874aea 4021 if (ssh_get_line) {
4022 if (!ssh_get_line("login as: ",
4023 username, sizeof(username), FALSE)) {
4024 /*
4025 * get_line failed to get a username.
4026 * Terminate.
4027 */
4028 logevent("No username provided. Abandoning session.");
4029 ssh_state = SSH_STATE_CLOSED;
4030 crReturnV;
4031 }
4032 } else {
4033 c_write_str("login as: ");
4034 ssh_send_ok = 1;
4035 while (pos >= 0) {
4036 crWaitUntilV(!ispkt);
4037 while (inlen--)
4038 switch (c = *in++) {
4039 case 10:
4040 case 13:
4041 username[pos] = 0;
4042 pos = -1;
4043 break;
4044 case 8:
4045 case 127:
4046 if (pos > 0) {
4047 c_write_str("\b \b");
4048 pos--;
4049 }
4050 break;
4051 case 21:
4052 case 27:
4053 while (pos > 0) {
4054 c_write_str("\b \b");
4055 pos--;
4056 }
4057 break;
4058 case 3:
4059 case 4:
93b581bd 4060 cleanup_exit(0);
32874aea 4061 break;
4062 default:
4063 if (((c >= ' ' && c <= '~') ||
51b2fb65 4064 ((unsigned char) c >= 160))
4065 && pos < sizeof(username)-1) {
32874aea 4066 username[pos++] = c;
4067 c_write(&c, 1);
4068 }
4069 break;
4070 }
4071 }
4072 }
1408a877 4073 c_write_str("\r\n");
7cca0d81 4074 username[strcspn(username, "\n\r")] = '\0';
4075 } else {
4076 char stuff[200];
4077 strncpy(username, cfg.username, 99);
4078 username[99] = '\0';
65a22376 4079 if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
7cca0d81 4080 sprintf(stuff, "Using username \"%s\".\r\n", username);
1408a877 4081 c_write_str(stuff);
7cca0d81 4082 }
4083 }
7e9b7f4b 4084 got_username = TRUE;
7cca0d81 4085
65a22376 4086 /*
1408a877 4087 * Send an authentication request using method "none": (a)
4088 * just in case it succeeds, and (b) so that we know what
4089 * authentication methods we can usefully try next.
65a22376 4090 */
00db133f 4091 ssh_pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
4092
1408a877 4093 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
4094 ssh2_pkt_addstring(username);
32874aea 4095 ssh2_pkt_addstring("ssh-connection"); /* service requested */
1408a877 4096 ssh2_pkt_addstring("none"); /* method */
4097 ssh2_pkt_send();
4098 type = AUTH_TYPE_NONE;
4099 gotit = FALSE;
4100 we_are_in = FALSE;
7cca0d81 4101
1408a877 4102 tried_pubkey_config = FALSE;
1983e559 4103 tried_agent = FALSE;
b3186d64 4104 tried_keyb_inter = FALSE;
4105 kbd_inter_running = FALSE;
396778f1 4106 /* Load the pub half of cfg.keyfile so we notice if it's in Pageant */
4107 if (*cfg.keyfile) {
231ee168 4108 int keytype;
4109 logeventf("Reading private key file \"%.150s\"", cfg.keyfile);
4110 keytype = key_type(cfg.keyfile);
4111 if (keytype == SSH_KEYTYPE_SSH2)
4112 publickey_blob = ssh2_userkey_loadpub(cfg.keyfile, NULL,
4113 &publickey_bloblen);
4114 else {
4115 char msgbuf[256];
4116 logeventf("Unable to use this key file (%s)",
4117 key_type_to_str(keytype));
4118 sprintf(msgbuf, "Unable to use key file \"%.150s\" (%s)\r\n",
4119 cfg.keyfile, key_type_to_str(keytype));
4120 c_write_str(msgbuf);
4121 publickey_blob = NULL;
4122 }
396778f1 4123 } else
4124 publickey_blob = NULL;
65a22376 4125
1408a877 4126 while (1) {
4127 /*
4128 * Wait for the result of the last authentication request.
4129 */
4130 if (!gotit)
4131 crWaitUntilV(ispkt);
4132 while (pktin.type == SSH2_MSG_USERAUTH_BANNER) {
32874aea 4133 char *banner;
4134 int size;
4135 /*
4136 * Don't show the banner if we're operating in
4137 * non-verbose non-interactive mode. (It's probably
4138 * a script, which means nobody will read the
4139 * banner _anyway_, and moreover the printing of
4140 * the banner will screw up processing on the
4141 * output of (say) plink.)
4142 */
4143 if (flags & (FLAG_VERBOSE | FLAG_INTERACTIVE)) {
4144 ssh2_pkt_getstring(&banner, &size);
4145 if (banner)
4146 c_write_untrusted(banner, size);
4147 }
1408a877 4148 crWaitUntilV(ispkt);
4149 }
4150 if (pktin.type == SSH2_MSG_USERAUTH_SUCCESS) {
4151 logevent("Access granted");
4152 we_are_in = TRUE;
4153 break;
4154 }
65a22376 4155
b3186d64 4156 if (kbd_inter_running &&
4157 pktin.type == SSH2_MSG_USERAUTH_INFO_REQUEST) {
4158 /*
4159 * This is a further prompt in keyboard-interactive
4160 * authentication. Do nothing.
4161 */
6bb26b30 4162 } else if (pktin.type != SSH2_MSG_USERAUTH_FAILURE) {
b3186d64 4163 bombout(("Strange packet received during authentication: type %d",
1408a877 4164 pktin.type));
38c4a8da 4165 crReturnV;
65a22376 4166 }
4167
1408a877 4168 gotit = FALSE;
65a22376 4169
1408a877 4170 /*
4171 * OK, we're now sitting on a USERAUTH_FAILURE message, so
4172 * we can look at the string in it and know what we can
4173 * helpfully try next.
4174 */
b3186d64 4175 if (pktin.type == SSH2_MSG_USERAUTH_FAILURE) {
1408a877 4176 char *methods;
4177 int methlen;
4178 ssh2_pkt_getstring(&methods, &methlen);
b3186d64 4179 kbd_inter_running = FALSE;
1408a877 4180 if (!ssh2_pkt_getbool()) {
4181 /*
4182 * We have received an unequivocal Access
4183 * Denied. This can translate to a variety of
4184 * messages:
4185 *
4186 * - if we'd just tried "none" authentication,
4187 * it's not worth printing anything at all
4188 *
4189 * - if we'd just tried a public key _offer_,
4190 * the message should be "Server refused our
4191 * key" (or no message at all if the key
4192 * came from Pageant)
4193 *
4194 * - if we'd just tried anything else, the
4195 * message really should be "Access denied".
4196 *
4197 * Additionally, if we'd just tried password
4198 * authentication, we should break out of this
4199 * whole loop so as to go back to the username
4200 * prompt.
4201 */
4202 if (type == AUTH_TYPE_NONE) {
4203 /* do nothing */
4204 } else if (type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD ||
4205 type == AUTH_TYPE_PUBLICKEY_OFFER_QUIET) {
4206 if (type == AUTH_TYPE_PUBLICKEY_OFFER_LOUD)
4207 c_write_str("Server refused our key\r\n");
4208 logevent("Server refused public key");
4bdf7c46 4209 } else if (type == AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET) {
4210 /* server declined keyboard-interactive; ignore */
1408a877 4211 } else {
4212 c_write_str("Access denied\r\n");
4213 logevent("Access denied");
4214 if (type == AUTH_TYPE_PASSWORD) {
4215 we_are_in = FALSE;
4216 break;
4217 }
4218 }
4219 } else {
4220 c_write_str("Further authentication required\r\n");
4221 logevent("Further authentication required");
4222 }
65a22376 4223
32874aea 4224 can_pubkey =
4225 in_commasep_string("publickey", methods, methlen);
4226 can_passwd =
4227 in_commasep_string("password", methods, methlen);
f091e308 4228 can_keyb_inter = cfg.try_ki_auth &&
761187b6 4229 in_commasep_string("keyboard-interactive", methods, methlen);
1408a877 4230 }
65a22376 4231
1408a877 4232 method = 0;
00db133f 4233 ssh_pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
65a22376 4234
78afa559 4235 if (!method && can_pubkey && agent_exists() && !tried_agent) {
1983e559 4236 /*
4237 * Attempt public-key authentication using Pageant.
4238 */
4239 static unsigned char request[5], *response, *p;
4240 static int responselen;
4241 static int i, nkeys;
4242 static int authed = FALSE;
4243 void *r;
4244
00db133f 4245 ssh_pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
4246
1983e559 4247 tried_agent = TRUE;
4248
4249 logevent("Pageant is running. Requesting keys.");
4250
4251 /* Request the keys held by the agent. */
4252 PUT_32BIT(request, 1);
4253 request[4] = SSH2_AGENTC_REQUEST_IDENTITIES;
4254 agent_query(request, 5, &r, &responselen);
32874aea 4255 response = (unsigned char *) r;
95797139 4256 if (response && responselen >= 5 &&
32874aea 4257 response[4] == SSH2_AGENT_IDENTITIES_ANSWER) {
1983e559 4258 p = response + 5;
32874aea 4259 nkeys = GET_32BIT(p);
4260 p += 4;
4261 {
4262 char buf[64];
4263 sprintf(buf, "Pageant has %d SSH2 keys", nkeys);
4264 logevent(buf);
4265 }
1983e559 4266 for (i = 0; i < nkeys; i++) {
4267 static char *pkblob, *alg, *commentp;
4268 static int pklen, alglen, commentlen;
4269 static int siglen, retlen, len;
4270 static char *q, *agentreq, *ret;
2d466ffd 4271 void *vret;
1983e559 4272
32874aea 4273 {
4274 char buf[64];
4275 sprintf(buf, "Trying Pageant key #%d", i);
4276 logevent(buf);
4277 }
4278 pklen = GET_32BIT(p);
4279 p += 4;
396778f1 4280 if (publickey_blob &&
4281 pklen == publickey_bloblen &&
4282 !memcmp(p, publickey_blob, publickey_bloblen)) {
4283 logevent("This key matches configured key file");
4284 tried_pubkey_config = 1;
4285 }
32874aea 4286 pkblob = p;
4287 p += pklen;
1983e559 4288 alglen = GET_32BIT(pkblob);
4289 alg = pkblob + 4;
32874aea 4290 commentlen = GET_32BIT(p);
4291 p += 4;
4292 commentp = p;
4293 p += commentlen;
1983e559 4294 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
4295 ssh2_pkt_addstring(username);
32874aea 4296 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4297 ssh2_pkt_addstring("publickey"); /* method */
4298 ssh2_pkt_addbool(FALSE); /* no signature included */
1983e559 4299 ssh2_pkt_addstring_start();
4300 ssh2_pkt_addstring_data(alg, alglen);
4301 ssh2_pkt_addstring_start();
4302 ssh2_pkt_addstring_data(pkblob, pklen);
4303 ssh2_pkt_send();
4304
4305 crWaitUntilV(ispkt);
4306 if (pktin.type != SSH2_MSG_USERAUTH_PK_OK) {
4307 logevent("Key refused");
4308 continue;
4309 }
4310
32874aea 4311 if (flags & FLAG_VERBOSE) {
4312 c_write_str
4313 ("Authenticating with public key \"");
4314 c_write(commentp, commentlen);
4315 c_write_str("\" from agent\r\n");
4316 }
1983e559 4317
4318 /*
4319 * Server is willing to accept the key.
4320 * Construct a SIGN_REQUEST.
4321 */
4322 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
4323 ssh2_pkt_addstring(username);
32874aea 4324 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4325 ssh2_pkt_addstring("publickey"); /* method */
1983e559 4326 ssh2_pkt_addbool(TRUE);
4327 ssh2_pkt_addstring_start();
4328 ssh2_pkt_addstring_data(alg, alglen);
4329 ssh2_pkt_addstring_start();
4330 ssh2_pkt_addstring_data(pkblob, pklen);
4331
4332 siglen = pktout.length - 5 + 4 + 20;
32874aea 4333 len = 1; /* message type */
4334 len += 4 + pklen; /* key blob */
4335 len += 4 + siglen; /* data to sign */
4336 len += 4; /* flags */
1983e559 4337 agentreq = smalloc(4 + len);
4338 PUT_32BIT(agentreq, len);
4339 q = agentreq + 4;
4340 *q++ = SSH2_AGENTC_SIGN_REQUEST;
32874aea 4341 PUT_32BIT(q, pklen);
4342 q += 4;
4343 memcpy(q, pkblob, pklen);
4344 q += pklen;
4345 PUT_32BIT(q, siglen);
4346 q += 4;
1983e559 4347 /* Now the data to be signed... */
32874aea 4348 PUT_32BIT(q, 20);
4349 q += 4;
4350 memcpy(q, ssh2_session_id, 20);
4351 q += 20;
4352 memcpy(q, pktout.data + 5, pktout.length - 5);
4353 q += pktout.length - 5;
1983e559 4354 /* And finally the (zero) flags word. */
4355 PUT_32BIT(q, 0);
2d466ffd 4356 agent_query(agentreq, len + 4, &vret, &retlen);
4357 ret = vret;
1983e559 4358 sfree(agentreq);
4359 if (ret) {
4360 if (ret[4] == SSH2_AGENT_SIGN_RESPONSE) {
4361 logevent("Sending Pageant's response");
4362 ssh2_pkt_addstring_start();
32874aea 4363 ssh2_pkt_addstring_data(ret + 9,
4364 GET_32BIT(ret +
4365 5));
1983e559 4366 ssh2_pkt_send();
4367 authed = TRUE;
4368 break;
4369 } else {
32874aea 4370 logevent
4371 ("Pageant failed to answer challenge");
1983e559 4372 sfree(ret);
4373 }
4374 }
4375 }
4376 if (authed)
4377 continue;
4378 }
4379 }
4380
231ee168 4381 if (!method && can_pubkey && publickey_blob
32874aea 4382 && !tried_pubkey_config) {
1408a877 4383 unsigned char *pub_blob;
4384 char *algorithm, *comment;
4385 int pub_blob_len;
65a22376 4386
1408a877 4387 tried_pubkey_config = TRUE;
65a22376 4388
00db133f 4389 ssh_pkt_ctx |= SSH2_PKTCTX_PUBLICKEY;
4390
65a22376 4391 /*
1408a877 4392 * Try the public key supplied in the configuration.
4393 *
4394 * First, offer the public blob to see if the server is
4395 * willing to accept it.
65a22376 4396 */
1408a877 4397 pub_blob = ssh2_userkey_loadpub(cfg.keyfile, &algorithm,
4398 &pub_blob_len);
4399 if (pub_blob) {
4400 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
4401 ssh2_pkt_addstring(username);
32874aea 4402 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4403 ssh2_pkt_addstring("publickey"); /* method */
4404 ssh2_pkt_addbool(FALSE); /* no signature included */
1408a877 4405 ssh2_pkt_addstring(algorithm);
4406 ssh2_pkt_addstring_start();
4407 ssh2_pkt_addstring_data(pub_blob, pub_blob_len);
4408 ssh2_pkt_send();
32874aea 4409 logevent("Offered public key"); /* FIXME */
1408a877 4410
4411 crWaitUntilV(ispkt);
4412 if (pktin.type != SSH2_MSG_USERAUTH_PK_OK) {
4413 gotit = TRUE;
4414 type = AUTH_TYPE_PUBLICKEY_OFFER_LOUD;
32874aea 4415 continue; /* key refused; give up on it */
1408a877 4416 }
65a22376 4417
1408a877 4418 logevent("Offer of public key accepted");
65a22376 4419 /*
1408a877 4420 * Actually attempt a serious authentication using
4421 * the key.
65a22376 4422 */
1408a877 4423 if (ssh2_userkey_encrypted(cfg.keyfile, &comment)) {
32874aea 4424 sprintf(pwprompt,
4425 "Passphrase for key \"%.100s\": ",
4426 comment);
1408a877 4427 need_pw = TRUE;
4428 } else {
4429 need_pw = FALSE;
4430 }
4431 c_write_str("Authenticating with public key \"");
4432 c_write_str(comment);
4433 c_write_str("\"\r\n");
4434 method = AUTH_PUBLICKEY_FILE;
65a22376 4435 }
1408a877 4436 }
4437
af659722 4438 if (!method && can_keyb_inter && !tried_keyb_inter) {
4439 method = AUTH_KEYBOARD_INTERACTIVE;
4440 type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
4441 tried_keyb_inter = TRUE;
4442
00db133f 4443 ssh_pkt_ctx |= SSH2_PKTCTX_KBDINTER;
4444
af659722 4445 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
4446 ssh2_pkt_addstring(username);
4447 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4448 ssh2_pkt_addstring("keyboard-interactive"); /* method */
4449 ssh2_pkt_addstring(""); /* lang */
4450 ssh2_pkt_addstring("");
4451 ssh2_pkt_send();
4452
4453 crWaitUntilV(ispkt);
4454 if (pktin.type != SSH2_MSG_USERAUTH_INFO_REQUEST) {
4455 if (pktin.type == SSH2_MSG_USERAUTH_FAILURE)
4456 gotit = TRUE;
4457 logevent("Keyboard-interactive authentication refused");
4458 type = AUTH_TYPE_KEYBOARD_INTERACTIVE_QUIET;
4459 continue;
4460 }
4461
4462 kbd_inter_running = TRUE;
4463 }
4464
4465 if (kbd_inter_running) {
4466 method = AUTH_KEYBOARD_INTERACTIVE;
4467 type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
4468 tried_keyb_inter = TRUE;
4469
00db133f 4470 ssh_pkt_ctx |= SSH2_PKTCTX_KBDINTER;
4471
af659722 4472 /* We've got packet with that "interactive" info
4473 dump banners, and set its prompt as ours */
4474 {
4475 char *name, *inst, *lang, *prompt;
4476 int name_len, inst_len, lang_len, prompt_len;
4477 ssh2_pkt_getstring(&name, &name_len);
4478 ssh2_pkt_getstring(&inst, &inst_len);
4479 ssh2_pkt_getstring(&lang, &lang_len);
4480 if (name_len > 0)
4481 c_write_untrusted(name, name_len);
4482 if (inst_len > 0)
4483 c_write_untrusted(inst, inst_len);
4484 num_prompts = ssh2_pkt_getuint32();
4485
4486 ssh2_pkt_getstring(&prompt, &prompt_len);
4487 strncpy(pwprompt, prompt, sizeof(pwprompt));
2c2f4dba 4488 pwprompt[prompt_len < sizeof(pwprompt) ?
4489 prompt_len : sizeof(pwprompt)-1] = '\0';
af659722 4490 need_pw = TRUE;
4491
4492 echo = ssh2_pkt_getbool();
4493 }
4494 }
4495
1408a877 4496 if (!method && can_passwd) {
4497 method = AUTH_PASSWORD;
00db133f 4498 ssh_pkt_ctx |= SSH2_PKTCTX_PASSWORD;
32874aea 4499 sprintf(pwprompt, "%.90s@%.90s's password: ", username,
4500 savedhost);
1408a877 4501 need_pw = TRUE;
4502 }
4503
4504 if (need_pw) {
fa17a66e 4505 if (ssh_get_line) {
4506 if (!ssh_get_line(pwprompt, password,
32874aea 4507 sizeof(password), TRUE)) {
1408a877 4508 /*
fa17a66e 4509 * get_line failed to get a password (for
4510 * example because one was supplied on the
4511 * command line which has already failed to
4512 * work). Terminate.
1408a877 4513 */
2bc6a386 4514 ssh2_pkt_init(SSH2_MSG_DISCONNECT);
4515 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION);
4516 ssh2_pkt_addstring
4517 ("No more passwords available to try");
4518 ssh2_pkt_addstring("en"); /* language tag */
4519 ssh2_pkt_send();
247308b5 4520 logevent("Unable to authenticate");
2bc6a386 4521 connection_fatal("Unable to authenticate");
1408a877 4522 ssh_state = SSH_STATE_CLOSED;
4523 crReturnV;
4524 }
4525 } else {
4526 static int pos = 0;
4527 static char c;
4528
761187b6 4529 c_write_untrusted(pwprompt, strlen(pwprompt));
1408a877 4530 ssh_send_ok = 1;
4531
4532 pos = 0;
4533 while (pos >= 0) {
4534 crWaitUntilV(!ispkt);
32874aea 4535 while (inlen--)
4536 switch (c = *in++) {
4537 case 10:
4538 case 13:
4539 password[pos] = 0;
4540 pos = -1;
4541 break;
4542 case 8:
4543 case 127:
4544 if (pos > 0)
4545 pos--;
4546 break;
4547 case 21:
4548 case 27:
4549 pos = 0;
4550 break;
4551 case 3:
4552 case 4:
93b581bd 4553 cleanup_exit(0);
32874aea 4554 break;
4555 default:
51b2fb65 4556 if (pos < sizeof(password)-1)
32874aea 4557 password[pos++] = c;
4558 break;
4559 }
65a22376 4560 }
1408a877 4561 c_write_str("\r\n");
65a22376 4562 }
65a22376 4563 }
65a22376 4564
1408a877 4565 if (method == AUTH_PUBLICKEY_FILE) {
4566 /*
4567 * We have our passphrase. Now try the actual authentication.
4568 */
4569 struct ssh2_userkey *key;
65a22376 4570
1408a877 4571 key = ssh2_load_userkey(cfg.keyfile, password);
4572 if (key == SSH2_WRONG_PASSPHRASE || key == NULL) {
4573 if (key == SSH2_WRONG_PASSPHRASE) {
4574 c_write_str("Wrong passphrase\r\n");
4575 tried_pubkey_config = FALSE;
4576 } else {
4577 c_write_str("Unable to load private key\r\n");
4578 tried_pubkey_config = TRUE;
4579 }
4580 /* Send a spurious AUTH_NONE to return to the top. */
4581 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
4582 ssh2_pkt_addstring(username);
32874aea 4583 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4584 ssh2_pkt_addstring("none"); /* method */
1408a877 4585 ssh2_pkt_send();
4586 type = AUTH_TYPE_NONE;
4587 } else {
4588 unsigned char *blob, *sigdata;
4589 int blob_len, sigdata_len;
65a22376 4590
1408a877 4591 /*
4592 * We have loaded the private key and the server
4593 * has announced that it's willing to accept it.
4594 * Hallelujah. Generate a signature and send it.
4595 */
4596 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
4597 ssh2_pkt_addstring(username);
32874aea 4598 ssh2_pkt_addstring("ssh-connection"); /* service requested */
4599 ssh2_pkt_addstring("publickey"); /* method */
1408a877 4600 ssh2_pkt_addbool(TRUE);
4601 ssh2_pkt_addstring(key->alg->name);
4602 blob = key->alg->public_blob(key->data, &blob_len);
4603 ssh2_pkt_addstring_start();
4604 ssh2_pkt_addstring_data(blob, blob_len);
4605 sfree(blob);
4606
4607 /*
4608 * The data to be signed is:
4609 *
4610 * string session-id
4611 *
4612 * followed by everything so far placed in the
4613 * outgoing packet.
4614 */
4615 sigdata_len = pktout.length - 5 + 4 + 20;
4616 sigdata = smalloc(sigdata_len);
4617 PUT_32BIT(sigdata, 20);
32874aea 4618 memcpy(sigdata + 4, ssh2_session_id, 20);
4619 memcpy(sigdata + 24, pktout.data + 5,
4620 pktout.length - 5);
4621 blob =
4622 key->alg->sign(key->data, sigdata, sigdata_len,
4623 &blob_len);
1408a877 4624 ssh2_pkt_addstring_start();
4625 ssh2_pkt_addstring_data(blob, blob_len);
4626 sfree(blob);
4627 sfree(sigdata);
4628
4629 ssh2_pkt_send();
4630 type = AUTH_TYPE_PUBLICKEY;
4631 }
4632 } else if (method == AUTH_PASSWORD) {
65a22376 4633 /*
1408a877 4634 * We send the password packet lumped tightly together with
4635 * an SSH_MSG_IGNORE packet. The IGNORE packet contains a
4636 * string long enough to make the total length of the two
4637 * packets constant. This should ensure that a passive
4638 * listener doing traffic analyis can't work out the length
4639 * of the password.
4640 *
4641 * For this to work, we need an assumption about the
4642 * maximum length of the password packet. I think 256 is
4643 * pretty conservative. Anyone using a password longer than
4644 * that probably doesn't have much to worry about from
4645 * people who find out how long their password is!
65a22376 4646 */
4647 ssh2_pkt_init(SSH2_MSG_USERAUTH_REQUEST);
4648 ssh2_pkt_addstring(username);
32874aea 4649 ssh2_pkt_addstring("ssh-connection"); /* service requested */
1408a877 4650 ssh2_pkt_addstring("password");
4651 ssh2_pkt_addbool(FALSE);
4652 ssh2_pkt_addstring(password);
4653 ssh2_pkt_defer();
65a22376 4654 /*
1408a877 4655 * We'll include a string that's an exact multiple of the
4656 * cipher block size. If the cipher is NULL for some
4657 * reason, we don't do this trick at all because we gain
4658 * nothing by it.
65a22376 4659 */
32874aea 4660 if (cscipher) {
4661 int stringlen, i;
4662
4663 stringlen = (256 - deferred_len);
4664 stringlen += cscipher->blksize - 1;
4665 stringlen -= (stringlen % cscipher->blksize);
4666 if (cscomp) {
4667 /*
4668 * Temporarily disable actual compression,
4669 * so we can guarantee to get this string
4670 * exactly the length we want it. The
4671 * compression-disabling routine should
4672 * return an integer indicating how many
4673 * bytes we should adjust our string length
4674 * by.
4675 */
4676 stringlen -= cscomp->disable_compression();
4677 }
1408a877 4678 ssh2_pkt_init(SSH2_MSG_IGNORE);
4679 ssh2_pkt_addstring_start();
6e9e9520 4680 for (i = 0; i < stringlen; i++) {
32874aea 4681 char c = (char) random_byte();
4682 ssh2_pkt_addstring_data(&c, 1);
65a22376 4683 }
1408a877 4684 ssh2_pkt_defer();
65a22376 4685 }
39065bed 4686 ssh_pkt_defersend();
0d43337a 4687 logevent("Sent password");
1408a877 4688 type = AUTH_TYPE_PASSWORD;
761187b6 4689 } else if (method == AUTH_KEYBOARD_INTERACTIVE) {
4690 ssh2_pkt_init(SSH2_MSG_USERAUTH_INFO_RESPONSE);
4691 ssh2_pkt_adduint32(num_prompts);
4692 ssh2_pkt_addstring(password);
4693 memset(password, 0, sizeof(password));
4694 ssh2_pkt_send();
4695 type = AUTH_TYPE_KEYBOARD_INTERACTIVE;
1408a877 4696 } else {
32874aea 4697 c_write_str
4698 ("No supported authentication methods left to try!\r\n");
4699 logevent
4700 ("No supported authentications offered. Disconnecting");
1408a877 4701 ssh2_pkt_init(SSH2_MSG_DISCONNECT);
4702 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION);
32874aea 4703 ssh2_pkt_addstring
4704 ("No supported authentication methods available");
4705 ssh2_pkt_addstring("en"); /* language tag */
1408a877 4706 ssh2_pkt_send();
4707 ssh_state = SSH_STATE_CLOSED;
4708 crReturnV;
65a22376 4709 }
65a22376 4710 }
1408a877 4711 } while (!we_are_in);
7cca0d81 4712
4713 /*
4714 * Now we're authenticated for the connection protocol. The
4715 * connection protocol will automatically have started at this
4716 * point; there's no need to send SERVICE_REQUEST.
4717 */
4718
4719 /*
4720 * So now create a channel with a session in it.
4721 */
d2371c81 4722 ssh_channels = newtree234(ssh_channelcmp);
dcbde236 4723 mainchan = smalloc(sizeof(struct ssh_channel));
d2371c81 4724 mainchan->localid = alloc_channel_id();
7cca0d81 4725 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
4726 ssh2_pkt_addstring("session");
d211621f 4727 ssh2_pkt_adduint32(mainchan->localid);
5471d09a 4728 mainchan->v.v2.locwindow = OUR_V2_WINSIZE;
4729 ssh2_pkt_adduint32(mainchan->v.v2.locwindow); /* our window size */
32874aea 4730 ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
7cca0d81 4731 ssh2_pkt_send();
4732 crWaitUntilV(ispkt);
4733 if (pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
32874aea 4734 bombout(("Server refused to open a session"));
4735 crReturnV;
4736 /* FIXME: error data comes back in FAILURE packet */
7cca0d81 4737 }
d211621f 4738 if (ssh2_pkt_getuint32() != mainchan->localid) {
32874aea 4739 bombout(("Server's channel confirmation cited wrong channel"));
4740 crReturnV;
7cca0d81 4741 }
d211621f 4742 mainchan->remoteid = ssh2_pkt_getuint32();
783415f8 4743 mainchan->type = CHAN_MAINSESSION;
4744 mainchan->closes = 0;
5471d09a 4745 mainchan->v.v2.remwindow = ssh2_pkt_getuint32();
4746 mainchan->v.v2.remmaxpkt = ssh2_pkt_getuint32();
4747 bufchain_init(&mainchan->v.v2.outbuffer);
783415f8 4748 add234(ssh_channels, mainchan);
7cca0d81 4749 logevent("Opened channel for session");
4750
4751 /*
783415f8 4752 * Potentially enable X11 forwarding.
4753 */
4754 if (cfg.x11_forward) {
32874aea 4755 char proto[20], data[64];
4756 logevent("Requesting X11 forwarding");
4757 x11_invent_auth(proto, sizeof(proto), data, sizeof(data));
4758 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
4759 ssh2_pkt_adduint32(mainchan->remoteid);
4760 ssh2_pkt_addstring("x11-req");
4761 ssh2_pkt_addbool(1); /* want reply */
4762 ssh2_pkt_addbool(0); /* many connections */
4763 ssh2_pkt_addstring(proto);
4764 ssh2_pkt_addstring(data);
4765 ssh2_pkt_adduint32(0); /* screen number */
4766 ssh2_pkt_send();
4767
4768 do {
4769 crWaitUntilV(ispkt);
4770 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
4771 unsigned i = ssh2_pkt_getuint32();
4772 struct ssh_channel *c;
4773 c = find234(ssh_channels, &i, ssh_channelfind);
4774 if (!c)
4775 continue; /* nonexistent channel */
5471d09a 4776 c->v.v2.remwindow += ssh2_pkt_getuint32();
32874aea 4777 }
4778 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
4779
4780 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
4781 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
c9886e66 4782 bombout(("Unexpected response to X11 forwarding request:"
4783 " packet type %d", pktin.type));
32874aea 4784 crReturnV;
4785 }
4786 logevent("X11 forwarding refused");
4787 } else {
4788 logevent("X11 forwarding enabled");
783415f8 4789 ssh_X11_fwd_enabled = TRUE;
32874aea 4790 }
783415f8 4791 }
4792
4793 /*
bc240b21 4794 * Enable port forwardings.
4795 */
4796 {
4797 static char *e; /* preserve across crReturn */
4798 char type;
4799 int n;
a4fc0d74 4800 int sport,dport,sserv,dserv;
bc240b21 4801 char sports[256], dports[256], host[256];
4802 char buf[1024];
a4fc0d74 4803 struct servent *se;
bc240b21 4804
4805 ssh_rportfwds = newtree234(ssh_rportcmp_ssh2);
4806 /* Add port forwardings. */
4807 e = cfg.portfwd;
4808 while (*e) {
4809 type = *e++;
4810 n = 0;
4811 while (*e && *e != '\t')
4812 sports[n++] = *e++;
4813 sports[n] = 0;
4814 if (*e == '\t')
4815 e++;
4816 n = 0;
4817 while (*e && *e != ':')
4818 host[n++] = *e++;
4819 host[n] = 0;
4820 if (*e == ':')
4821 e++;
4822 n = 0;
4823 while (*e)
4824 dports[n++] = *e++;
4825 dports[n] = 0;
4826 e++;
4827 dport = atoi(dports);
a4fc0d74 4828 dserv = 0;
4829 if (dport == 0) {
4830 dserv = 1;
4831 se = getservbyname(dports, NULL);
4832 if (se != NULL) {
4833 dport = ntohs(se->s_port);
4834 } else {
4835 sprintf(buf,
4836 "Service lookup failed for destination port \"%s\"",
4837 dports);
4838 logevent(buf);
4839 }
4840 }
bc240b21 4841 sport = atoi(sports);
a4fc0d74 4842 sserv = 0;
4843 if (sport == 0) {
4844 sserv = 1;
4845 se = getservbyname(sports, NULL);
4846 if (se != NULL) {
4847 sport = ntohs(se->s_port);
4848 } else {
4849 sprintf(buf,
4850 "Service lookup failed for source port \"%s\"",
4851 sports);
4852 logevent(buf);
4853 }
4854 }
bc240b21 4855 if (sport && dport) {
4856 if (type == 'L') {
4857 pfd_addforward(host, dport, sport);
a4fc0d74 4858 sprintf(buf, "Local port %.*s%.*s%d%.*s forwarding to"
4859 " %s:%.*s%.*s%d%.*s",
4860 sserv ? strlen(sports) : 0, sports,
4861 sserv, "(", sport, sserv, ")",
4862 host,
4863 dserv ? strlen(dports) : 0, dports,
4864 dserv, "(", dport, dserv, ")");
bc240b21 4865 logevent(buf);
4866 } else {
4867 struct ssh_rportfwd *pf;
4868 pf = smalloc(sizeof(*pf));
4869 strcpy(pf->dhost, host);
4870 pf->dport = dport;
4871 pf->sport = sport;
4872 if (add234(ssh_rportfwds, pf) != pf) {
4873 sprintf(buf,
95bc8819 4874 "Duplicate remote port forwarding to %s:%d",
bc240b21 4875 host, dport);
4876 logevent(buf);
4877 sfree(pf);
4878 } else {
a4fc0d74 4879 sprintf(buf, "Requesting remote port %.*s%.*s%d%.*s"
4880 " forward to %s:%.*s%.*s%d%.*s",
4881 sserv ? strlen(sports) : 0, sports,
4882 sserv, "(", sport, sserv, ")",
4883 host,
4884 dserv ? strlen(dports) : 0, dports,
4885 dserv, "(", dport, dserv, ")");
bc240b21 4886 logevent(buf);
4887 ssh2_pkt_init(SSH2_MSG_GLOBAL_REQUEST);
4888 ssh2_pkt_addstring("tcpip-forward");
4889 ssh2_pkt_addbool(1);/* want reply */
beefa433 4890 if (cfg.rport_acceptall)
4891 ssh2_pkt_addstring("0.0.0.0");
4892 else
4893 ssh2_pkt_addstring("127.0.0.1");
bc240b21 4894 ssh2_pkt_adduint32(sport);
4895 ssh2_pkt_send();
4896
4897 do {
4898 crWaitUntilV(ispkt);
4899 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
4900 unsigned i = ssh2_pkt_getuint32();
4901 struct ssh_channel *c;
4902 c = find234(ssh_channels, &i, ssh_channelfind);
4903 if (!c)
4904 continue;/* nonexistent channel */
5471d09a 4905 c->v.v2.remwindow += ssh2_pkt_getuint32();
bc240b21 4906 }
4907 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
4908
4909 if (pktin.type != SSH2_MSG_REQUEST_SUCCESS) {
4910 if (pktin.type != SSH2_MSG_REQUEST_FAILURE) {
c9886e66 4911 bombout(("Unexpected response to port "
4912 "forwarding request: packet type %d",
4913 pktin.type));
bc240b21 4914 crReturnV;
4915 }
4916 logevent("Server refused this port forwarding");
4917 } else {
4918 logevent("Remote port forwarding enabled");
4919 }
4920 }
4921 }
4922 }
4923 }
4924 }
4925
4926 /*
36c2a3e9 4927 * Potentially enable agent forwarding.
4928 */
4929 if (cfg.agentfwd && agent_exists()) {
32874aea 4930 logevent("Requesting OpenSSH-style agent forwarding");
4931 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
4932 ssh2_pkt_adduint32(mainchan->remoteid);
4933 ssh2_pkt_addstring("auth-agent-req@openssh.com");
4934 ssh2_pkt_addbool(1); /* want reply */
4935 ssh2_pkt_send();
4936
4937 do {
4938 crWaitUntilV(ispkt);
4939 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
4940 unsigned i = ssh2_pkt_getuint32();
4941 struct ssh_channel *c;
4942 c = find234(ssh_channels, &i, ssh_channelfind);
4943 if (!c)
4944 continue; /* nonexistent channel */
5471d09a 4945 c->v.v2.remwindow += ssh2_pkt_getuint32();
32874aea 4946 }
4947 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
4948
4949 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
4950 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
c9886e66 4951 bombout(("Unexpected response to agent forwarding request:"
4952 " packet type %d", pktin.type));
32874aea 4953 crReturnV;
4954 }
4955 logevent("Agent forwarding refused");
4956 } else {
4957 logevent("Agent forwarding enabled");
36c2a3e9 4958 ssh_agentfwd_enabled = TRUE;
32874aea 4959 }
36c2a3e9 4960 }
4961
4962 /*
7cca0d81 4963 * Now allocate a pty for the session.
4964 */
67779be7 4965 if (!cfg.nopty) {
32874aea 4966 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
4967 ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
4968 ssh2_pkt_addstring("pty-req");
4969 ssh2_pkt_addbool(1); /* want reply */
4970 ssh2_pkt_addstring(cfg.termtype);
4971 ssh2_pkt_adduint32(cols);
4972 ssh2_pkt_adduint32(rows);
4973 ssh2_pkt_adduint32(0); /* pixel width */
4974 ssh2_pkt_adduint32(0); /* pixel height */
4975 ssh2_pkt_addstring_start();
4976 ssh2_pkt_addstring_data("\0", 1); /* TTY_OP_END, no special options */
4977 ssh2_pkt_send();
4978 ssh_state = SSH_STATE_INTERMED;
4979
4980 do {
4981 crWaitUntilV(ispkt);
4982 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
4983 unsigned i = ssh2_pkt_getuint32();
4984 struct ssh_channel *c;
4985 c = find234(ssh_channels, &i, ssh_channelfind);
4986 if (!c)
4987 continue; /* nonexistent channel */
5471d09a 4988 c->v.v2.remwindow += ssh2_pkt_getuint32();
32874aea 4989 }
4990 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
4991
4992 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
4993 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
c9886e66 4994 bombout(("Unexpected response to pty request:"
4995 " packet type %d", pktin.type));
32874aea 4996 crReturnV;
4997 }
4998 c_write_str("Server refused to allocate pty\r\n");
4999 ssh_editing = ssh_echoing = 1;
5000 } else {
5001 logevent("Allocated pty");
5002 }
0965bee0 5003 } else {
32874aea 5004 ssh_editing = ssh_echoing = 1;
7cca0d81 5005 }
5006
5007 /*
fd5e5847 5008 * Start a shell or a remote command. We may have to attempt
5009 * this twice if the config data has provided a second choice
5010 * of command.
7cca0d81 5011 */
fd5e5847 5012 while (1) {
5013 int subsys;
5014 char *cmd;
5015
5016 if (ssh_fallback_cmd) {
5017 subsys = cfg.ssh_subsys2;
5018 cmd = cfg.remote_cmd_ptr2;
5019 } else {
5020 subsys = cfg.ssh_subsys;
5021 cmd = cfg.remote_cmd_ptr;
5022 }
5023
5024 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
5025 ssh2_pkt_adduint32(mainchan->remoteid); /* recipient channel */
5026 if (subsys) {
5027 ssh2_pkt_addstring("subsystem");
5028 ssh2_pkt_addbool(1); /* want reply */
5029 ssh2_pkt_addstring(cmd);
5030 } else if (*cmd) {
5031 ssh2_pkt_addstring("exec");
5032 ssh2_pkt_addbool(1); /* want reply */
5033 ssh2_pkt_addstring(cmd);
5034 } else {
5035 ssh2_pkt_addstring("shell");
5036 ssh2_pkt_addbool(1); /* want reply */
32874aea 5037 }
fd5e5847 5038 ssh2_pkt_send();
5039 do {
5040 crWaitUntilV(ispkt);
5041 if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
5042 unsigned i = ssh2_pkt_getuint32();
5043 struct ssh_channel *c;
5044 c = find234(ssh_channels, &i, ssh_channelfind);
5045 if (!c)
5046 continue; /* nonexistent channel */
5047 c->v.v2.remwindow += ssh2_pkt_getuint32();
5048 }
5049 } while (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
5050 if (pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
5051 if (pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
c9886e66 5052 bombout(("Unexpected response to shell/command request:"
5053 " packet type %d", pktin.type));
fd5e5847 5054 crReturnV;
5055 }
5056 /*
5057 * We failed to start the command. If this is the
5058 * fallback command, we really are finished; if it's
5059 * not, and if the fallback command exists, try falling
5060 * back to it before complaining.
5061 */
5062 if (!ssh_fallback_cmd && cfg.remote_cmd_ptr2 != NULL) {
5063 logevent("Primary command failed; attempting fallback");
5064 ssh_fallback_cmd = TRUE;
5065 continue;
5066 }
5067 bombout(("Server refused to start a shell/command"));
32874aea 5068 crReturnV;
fd5e5847 5069 } else {
5070 logevent("Started a shell/command");
32874aea 5071 }
fd5e5847 5072 break;
7cca0d81 5073 }
5074
6e48c3fe 5075 ssh_state = SSH_STATE_SESSION;
5076 if (size_needed)
5077 ssh_size();
3687d221 5078 if (eof_needed)
32874aea 5079 ssh_special(TS_EOF);
6e48c3fe 5080
7cca0d81 5081 /*
5082 * Transfer data!
5083 */
760e88b2 5084 ldisc_send(NULL, 0, 0); /* cause ldisc to notice changes */
8ccc75b0 5085 ssh_send_ok = 1;
7cca0d81 5086 while (1) {
32874aea 5087 static int try_send;
e5574168 5088 crReturnV;
32874aea 5089 try_send = FALSE;
7cca0d81 5090 if (ispkt) {
5091 if (pktin.type == SSH2_MSG_CHANNEL_DATA ||
32874aea 5092 pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
5093 char *data;
5094 int length;
5095 unsigned i = ssh2_pkt_getuint32();
5096 struct ssh_channel *c;
5097 c = find234(ssh_channels, &i, ssh_channelfind);
5098 if (!c)
5099 continue; /* nonexistent channel */
5100 if (pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
5101 ssh2_pkt_getuint32() != SSH2_EXTENDED_DATA_STDERR)
5102 continue; /* extended but not stderr */
5103 ssh2_pkt_getstring(&data, &length);
5104 if (data) {
5471d09a 5105 int bufsize;
5106 c->v.v2.locwindow -= length;
32874aea 5107 switch (c->type) {
5108 case CHAN_MAINSESSION:
5471d09a 5109 bufsize =
5110 from_backend(pktin.type ==
5111 SSH2_MSG_CHANNEL_EXTENDED_DATA,
5112 data, length);
32874aea 5113 break;
5114 case CHAN_X11:
5471d09a 5115 bufsize = x11_send(c->u.x11.s, data, length);
32874aea 5116 break;
d74d141c 5117 case CHAN_SOCKDATA:
5471d09a 5118 bufsize = pfd_send(c->u.pfd.s, data, length);
bc240b21 5119 break;
36c2a3e9 5120 case CHAN_AGENT:
32874aea 5121 while (length > 0) {
5122 if (c->u.a.lensofar < 4) {
5123 int l = min(4 - c->u.a.lensofar, length);
5124 memcpy(c->u.a.msglen + c->u.a.lensofar,
5125 data, l);
5126 data += l;
5127 length -= l;
5128 c->u.a.lensofar += l;
5129 }
5130 if (c->u.a.lensofar == 4) {
5131 c->u.a.totallen =
5132 4 + GET_32BIT(c->u.a.msglen);
5133 c->u.a.message = smalloc(c->u.a.totallen);
5134 memcpy(c->u.a.message, c->u.a.msglen, 4);
5135 }
5136 if (c->u.a.lensofar >= 4 && length > 0) {
5137 int l =
5138 min(c->u.a.totallen - c->u.a.lensofar,
5139 length);
5140 memcpy(c->u.a.message + c->u.a.lensofar,
5141 data, l);
5142 data += l;
5143 length -= l;
5144 c->u.a.lensofar += l;
5145 }
5146 if (c->u.a.lensofar == c->u.a.totallen) {
5147 void *reply, *sentreply;
5148 int replylen;
5149 agent_query(c->u.a.message,
5150 c->u.a.totallen, &reply,
5151 &replylen);
5152 if (reply)
5153 sentreply = reply;
5154 else {
5155 /* Fake SSH_AGENT_FAILURE. */
5156 sentreply = "\0\0\0\1\5";
5157 replylen = 5;
5158 }
5159 ssh2_add_channel_data(c, sentreply,
5160 replylen);
36c2a3e9 5161 try_send = TRUE;
32874aea 5162 if (reply)
5163 sfree(reply);
5164 sfree(c->u.a.message);
5165 c->u.a.lensofar = 0;
5166 }
5167 }
5471d09a 5168 bufsize = 0;
32874aea 5169 break;
5170 }
5171 /*
5471d09a 5172 * If we are not buffering too much data,
5173 * enlarge the window again at the remote side.
32874aea 5174 */
5471d09a 5175 if (bufsize < OUR_V2_WINSIZE)
5176 ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
32874aea 5177 }
7cca0d81 5178 } else if (pktin.type == SSH2_MSG_DISCONNECT) {
32874aea 5179 ssh_state = SSH_STATE_CLOSED;
d211621f 5180 logevent("Received disconnect message");
32874aea 5181 crReturnV;
d211621f 5182 } else if (pktin.type == SSH2_MSG_CHANNEL_EOF) {
32874aea 5183 unsigned i = ssh2_pkt_getuint32();
5184 struct ssh_channel *c;
5185
5186 c = find234(ssh_channels, &i, ssh_channelfind);
5187 if (!c)
5188 continue; /* nonexistent channel */
5189
5190 if (c->type == CHAN_X11) {
5191 /*
5192 * Remote EOF on an X11 channel means we should
5193 * wrap up and close the channel ourselves.
5194 */
5195 x11_close(c->u.x11.s);
5196 sshfwd_close(c);
5197 } else if (c->type == CHAN_AGENT) {
36c2a3e9 5198 sshfwd_close(c);
d74d141c 5199 } else if (c->type == CHAN_SOCKDATA) {
bc240b21 5200 pfd_close(c->u.pfd.s);
5201 sshfwd_close(c);
36c2a3e9 5202 }
d211621f 5203 } else if (pktin.type == SSH2_MSG_CHANNEL_CLOSE) {
32874aea 5204 unsigned i = ssh2_pkt_getuint32();
5205 struct ssh_channel *c;
5206
5207 c = find234(ssh_channels, &i, ssh_channelfind);
5208 if (!c)
5209 continue; /* nonexistent channel */
32874aea 5210 /* Do pre-close processing on the channel. */
5211 switch (c->type) {
5212 case CHAN_MAINSESSION:
5213 break; /* nothing to see here, move along */
5214 case CHAN_X11:
92f157bd 5215 if (c->u.x11.s != NULL)
5216 x11_close(c->u.x11.s);
5217 sshfwd_close(c);
32874aea 5218 break;
5219 case CHAN_AGENT:
92f157bd 5220 sshfwd_close(c);
32874aea 5221 break;
d74d141c 5222 case CHAN_SOCKDATA:
92f157bd 5223 if (c->u.pfd.s != NULL)
5224 pfd_close(c->u.pfd.s);
5225 sshfwd_close(c);
bc240b21 5226 break;
32874aea 5227 }
92f157bd 5228 if (c->closes == 0) {
5229 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
5230 ssh2_pkt_adduint32(c->remoteid);
5231 ssh2_pkt_send();
5232 }
32874aea 5233 del234(ssh_channels, c);
5471d09a 5234 bufchain_clear(&c->v.v2.outbuffer);
32874aea 5235 sfree(c);
5236
5237 /*
5238 * See if that was the last channel left open.
5239 */
5240 if (count234(ssh_channels) == 0) {
ca2914d1 5241#if 0
5242 /*
5243 * We used to send SSH_MSG_DISCONNECT here,
5244 * because I'd believed that _every_ conforming
5245 * SSH2 connection had to end with a disconnect
5246 * being sent by at least one side; apparently
5247 * I was wrong and it's perfectly OK to
5248 * unceremoniously slam the connection shut
5249 * when you're done, and indeed OpenSSH feels
5250 * this is more polite than sending a
5251 * DISCONNECT. So now we don't.
5252 */
32874aea 5253 logevent("All channels closed. Disconnecting");
5254 ssh2_pkt_init(SSH2_MSG_DISCONNECT);
5255 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION);
5256 ssh2_pkt_addstring("All open channels closed");
5257 ssh2_pkt_addstring("en"); /* language tag */
5258 ssh2_pkt_send();
ca2914d1 5259#endif
32874aea 5260 ssh_state = SSH_STATE_CLOSED;
5261 crReturnV;
5262 }
5263 continue; /* remote sends close; ignore (FIXME) */
7cca0d81 5264 } else if (pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
32874aea 5265 unsigned i = ssh2_pkt_getuint32();
5266 struct ssh_channel *c;
5267 c = find234(ssh_channels, &i, ssh_channelfind);
5268 if (!c)
5269 continue; /* nonexistent channel */
5471d09a 5270 c->v.v2.remwindow += ssh2_pkt_getuint32();
32874aea 5271 try_send = TRUE;
bc240b21 5272 } else if (pktin.type == SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
5273 unsigned i = ssh2_pkt_getuint32();
5274 struct ssh_channel *c;
5275 c = find234(ssh_channels, &i, ssh_channelfind);
5276 if (!c)
5277 continue; /* nonexistent channel */
5278 if (c->type != CHAN_SOCKDATA_DORMANT)
5279 continue; /* dunno why they're confirming this */
5280 c->remoteid = ssh2_pkt_getuint32();
5281 c->type = CHAN_SOCKDATA;
5471d09a 5282 c->v.v2.remwindow = ssh2_pkt_getuint32();
5283 c->v.v2.remmaxpkt = ssh2_pkt_getuint32();
5284 bufchain_init(&c->v.v2.outbuffer);
4ed34d25 5285 if (c->u.pfd.s)
5286 pfd_confirm(c->u.pfd.s);
5287 if (c->closes) {
5288 /*
5289 * We have a pending close on this channel,
5290 * which we decided on before the server acked
5291 * the channel open. So now we know the
5292 * remoteid, we can close it again.
5293 */
5294 ssh2_pkt_init(SSH2_MSG_CHANNEL_CLOSE);
5295 ssh2_pkt_adduint32(c->remoteid);
5296 ssh2_pkt_send();
5297 }
724cface 5298 } else if (pktin.type == SSH2_MSG_CHANNEL_OPEN_FAILURE) {
5299 unsigned i = ssh2_pkt_getuint32();
5300 struct ssh_channel *c;
5301 c = find234(ssh_channels, &i, ssh_channelfind);
5302 if (!c)
5303 continue; /* nonexistent channel */
5304 if (c->type != CHAN_SOCKDATA_DORMANT)
5305 continue; /* dunno why they're failing this */
5306
5307 logevent("Forwarded connection refused by server");
5308
5309 pfd_close(c->u.pfd.s);
5310
5311 del234(ssh_channels, c);
5312 sfree(c);
ebb0a590 5313 } else if (pktin.type == SSH2_MSG_CHANNEL_REQUEST) {
5314 unsigned localid;
5315 char *type;
5316 int typelen, want_reply;
5317 struct ssh_channel *c;
5318
5319 localid = ssh2_pkt_getuint32();
5320 ssh2_pkt_getstring(&type, &typelen);
5321 want_reply = ssh2_pkt_getbool();
5322
5323 /*
5324 * First, check that the channel exists. Otherwise,
5325 * we can instantly disconnect with a rude message.
5326 */
5327 c = find234(ssh_channels, &localid, ssh_channelfind);
5328 if (!c) {
5329 char buf[80];
5330 sprintf(buf, "Received channel request for nonexistent"
5331 " channel %d", localid);
5332 logevent(buf);
5333 ssh2_pkt_init(SSH2_MSG_DISCONNECT);
5334 ssh2_pkt_adduint32(SSH2_DISCONNECT_BY_APPLICATION);
5335 ssh2_pkt_addstring(buf);
5336 ssh2_pkt_addstring("en"); /* language tag */
5337 ssh2_pkt_send();
247308b5 5338 connection_fatal("%s", buf);
ebb0a590 5339 ssh_state = SSH_STATE_CLOSED;
5340 crReturnV;
5341 }
5342
5343 /*
d8d6c7e5 5344 * Having got the channel number, we now look at
5345 * the request type string to see if it's something
5346 * we recognise.
ebb0a590 5347 */
d8d6c7e5 5348 if (typelen == 11 && !memcmp(type, "exit-status", 11) &&
5349 c == mainchan) {
5350 /* We recognise "exit-status" on the primary channel. */
5351 char buf[100];
5352 ssh_exitcode = ssh2_pkt_getuint32();
5353 sprintf(buf, "Server sent command exit status %d",
5354 ssh_exitcode);
5355 logevent(buf);
5356 if (want_reply) {
5357 ssh2_pkt_init(SSH2_MSG_CHANNEL_SUCCESS);
5358 ssh2_pkt_adduint32(c->remoteid);
5359 ssh2_pkt_send();
5360 }
5361 } else {
5362 /*
5363 * This is a channel request we don't know
5364 * about, so we now either ignore the request
5365 * or respond with CHANNEL_FAILURE, depending
5366 * on want_reply.
5367 */
5368 if (want_reply) {
5369 ssh2_pkt_init(SSH2_MSG_CHANNEL_FAILURE);
5370 ssh2_pkt_adduint32(c->remoteid);
5371 ssh2_pkt_send();
5372 }
ebb0a590 5373 }
697d4856 5374 } else if (pktin.type == SSH2_MSG_GLOBAL_REQUEST) {
5375 char *type;
5376 int typelen, want_reply;
5377
5378 ssh2_pkt_getstring(&type, &typelen);
5379 want_reply = ssh2_pkt_getbool();
5380
5381 /*
5382 * We currently don't support any global requests
5383 * at all, so we either ignore the request or
5384 * respond with REQUEST_FAILURE, depending on
5385 * want_reply.
5386 */
5387 if (want_reply) {
5388 ssh2_pkt_init(SSH2_MSG_REQUEST_FAILURE);
5389 ssh2_pkt_send();
5390 }
783415f8 5391 } else if (pktin.type == SSH2_MSG_CHANNEL_OPEN) {
32874aea 5392 char *type;
5393 int typelen;
5394 char *error = NULL;
5395 struct ssh_channel *c;
bc240b21 5396 unsigned remid, winsize, pktsize;
32874aea 5397 ssh2_pkt_getstring(&type, &typelen);
5398 c = smalloc(sizeof(struct ssh_channel));
5399
bc240b21 5400 remid = ssh2_pkt_getuint32();
5401 winsize = ssh2_pkt_getuint32();
5402 pktsize = ssh2_pkt_getuint32();
5403
32874aea 5404 if (typelen == 3 && !memcmp(type, "x11", 3)) {
5405 if (!ssh_X11_fwd_enabled)
5406 error = "X11 forwarding is not enabled";
5407 else if (x11_init(&c->u.x11.s, cfg.x11_display, c) !=
5408 NULL) {
5409 error = "Unable to open an X11 connection";
5410 } else {
5411 c->type = CHAN_X11;
5412 }
bc240b21 5413 } else if (typelen == 15 &&
5414 !memcmp(type, "forwarded-tcpip", 15)) {
5415 struct ssh_rportfwd pf, *realpf;
5416 char *dummy;
5417 int dummylen;
5418 ssh2_pkt_getstring(&dummy, &dummylen);/* skip address */
5419 pf.sport = ssh2_pkt_getuint32();
5420 realpf = find234(ssh_rportfwds, &pf, NULL);
5421 if (realpf == NULL) {
5422 error = "Remote port is not recognised";
5423 } else {
5424 char *e = pfd_newconnect(&c->u.pfd.s, realpf->dhost,
5425 realpf->dport, c);
5426 char buf[1024];
5427 sprintf(buf, "Received remote port open request for %s:%d",
5428 realpf->dhost, realpf->dport);
5429 logevent(buf);
5430 if (e != NULL) {
5431 sprintf(buf, "Port open failed: %s", e);
5432 logevent(buf);
5433 error = "Port open failed";
5434 } else {
5435 logevent("Forwarded port opened successfully");
5436 c->type = CHAN_SOCKDATA;
5437 }
5438 }
32874aea 5439 } else if (typelen == 22 &&
36c2a3e9 5440 !memcmp(type, "auth-agent@openssh.com", 3)) {
32874aea 5441 if (!ssh_agentfwd_enabled)
5442 error = "Agent forwarding is not enabled";
36c2a3e9 5443 else {
32874aea 5444 c->type = CHAN_AGENT; /* identify channel type */
36c2a3e9 5445 c->u.a.lensofar = 0;
32874aea 5446 }
5447 } else {
5448 error = "Unsupported channel type requested";
5449 }
5450
bc240b21 5451 c->remoteid = remid;
32874aea 5452 if (error) {
5453 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_FAILURE);
5454 ssh2_pkt_adduint32(c->remoteid);
5455 ssh2_pkt_adduint32(SSH2_OPEN_CONNECT_FAILED);
5456 ssh2_pkt_addstring(error);
5457 ssh2_pkt_addstring("en"); /* language tag */
5458 ssh2_pkt_send();
5459 sfree(c);
5460 } else {
5461 c->localid = alloc_channel_id();
5462 c->closes = 0;
5471d09a 5463 c->v.v2.locwindow = OUR_V2_WINSIZE;
5464 c->v.v2.remwindow = winsize;
5465 c->v.v2.remmaxpkt = pktsize;
5466 bufchain_init(&c->v.v2.outbuffer);
32874aea 5467 add234(ssh_channels, c);
5468 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
5469 ssh2_pkt_adduint32(c->remoteid);
5470 ssh2_pkt_adduint32(c->localid);
5471d09a 5471 ssh2_pkt_adduint32(c->v.v2.locwindow);
32874aea 5472 ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
5473 ssh2_pkt_send();
5474 }
7cca0d81 5475 } else {
8d5de777 5476 bombout(("Strange packet received: type %d", pktin.type));
32874aea 5477 crReturnV;
7cca0d81 5478 }
5479 } else {
32874aea 5480 /*
5481 * We have spare data. Add it to the channel buffer.
5482 */
5483 ssh2_add_channel_data(mainchan, in, inlen);
5484 try_send = TRUE;
5485 }
5486 if (try_send) {
5487 int i;
5488 struct ssh_channel *c;
5489 /*
5490 * Try to send data on all channels if we can.
5491 */
5471d09a 5492 for (i = 0; NULL != (c = index234(ssh_channels, i)); i++) {
5493 int bufsize = ssh2_try_send(c);
5494 if (bufsize == 0) {
5495 switch (c->type) {
5496 case CHAN_MAINSESSION:
5497 /* stdin need not receive an unthrottle
5498 * notification since it will be polled */
5499 break;
5500 case CHAN_X11:
5501 x11_unthrottle(c->u.x11.s);
5502 break;
5503 case CHAN_AGENT:
5504 /* agent sockets are request/response and need no
5505 * buffer management */
5506 break;
5507 case CHAN_SOCKDATA:
5508 pfd_unthrottle(c->u.pfd.s);
5509 break;
5510 }
5511 }
5512 }
7cca0d81 5513 }
e5574168 5514 }
5515
5516 crFinishV;
5517}
5518
5519/*
7cca0d81 5520 * Handle the top-level SSH2 protocol.
5521 */
5522static void ssh2_protocol(unsigned char *in, int inlen, int ispkt)
5523{
5524 if (do_ssh2_transport(in, inlen, ispkt) == 0)
32874aea 5525 return;
7cca0d81 5526 do_ssh2_authconn(in, inlen, ispkt);
5527}
5528
5529/*
8df7a775 5530 * Called to set up the connection.
374330e2 5531 *
5532 * Returns an error message, or NULL on success.
374330e2 5533 */
2184a5d9 5534static char *ssh_init(char *host, int port, char **realhost, int nodelay)
32874aea 5535{
fb09bf1c 5536 char *p;
32874aea 5537
8f203108 5538#ifdef MSCRYPTOAPI
32874aea 5539 if (crypto_startup() == 0)
8f203108 5540 return "Microsoft high encryption pack not installed!";
5541#endif
374330e2 5542
8df7a775 5543 ssh_send_ok = 0;
0965bee0 5544 ssh_editing = 0;
5545 ssh_echoing = 0;
5471d09a 5546 ssh1_throttle_count = 0;
5547 ssh_overall_bufsize = 0;
fd5e5847 5548 ssh_fallback_cmd = 0;
8df7a775 5549
2184a5d9 5550 p = connect_to_host(host, port, realhost, nodelay);
fb09bf1c 5551 if (p != NULL)
5552 return p;
374330e2 5553
374330e2 5554 return NULL;
5555}
5556
5557/*
374330e2 5558 * Called to send data down the Telnet connection.
5559 */
5471d09a 5560static int ssh_send(char *buf, int len)
32874aea 5561{
f78051a1 5562 if (s == NULL || ssh_protocol == NULL)
5471d09a 5563 return 0;
374330e2 5564
5565 ssh_protocol(buf, len, 0);
5471d09a 5566
5567 return ssh_sendbuffer();
5568}
5569
5570/*
5571 * Called to query the current amount of buffered stdin data.
5572 */
5573static int ssh_sendbuffer(void)
5574{
5575 int override_value;
5576
5577 if (s == NULL || ssh_protocol == NULL)
5578 return 0;
5579
5580 /*
5581 * If the SSH socket itself has backed up, add the total backup
5582 * size on that to any individual buffer on the stdin channel.
5583 */
5584 override_value = 0;
5585 if (ssh_throttled_all)
5586 override_value = ssh_overall_bufsize;
5587
5588 if (ssh_version == 1) {
5589 return override_value;
5590 } else if (ssh_version == 2) {
5591 if (!mainchan || mainchan->closes > 0)
5592 return override_value;
5593 else
5594 return override_value + bufchain_size(&mainchan->v.v2.outbuffer);
5595 }
5596
5597 return 0;
374330e2 5598}
5599
5600/*
6e48c3fe 5601 * Called to set the size of the window from SSH's POV.
374330e2 5602 */
32874aea 5603static void ssh_size(void)
5604{
374330e2 5605 switch (ssh_state) {
5606 case SSH_STATE_BEFORE_SIZE:
3687d221 5607 case SSH_STATE_PREPACKET:
21248260 5608 case SSH_STATE_CLOSED:
374330e2 5609 break; /* do nothing */
5610 case SSH_STATE_INTERMED:
5611 size_needed = TRUE; /* buffer for later */
5612 break;
5613 case SSH_STATE_SESSION:
32874aea 5614 if (!cfg.nopty) {
5615 if (ssh_version == 1) {
5616 send_packet(SSH1_CMSG_WINDOW_SIZE,
5617 PKT_INT, rows, PKT_INT, cols,
5618 PKT_INT, 0, PKT_INT, 0, PKT_END);
5619 } else {
5620 ssh2_pkt_init(SSH2_MSG_CHANNEL_REQUEST);
5621 ssh2_pkt_adduint32(mainchan->remoteid);
5622 ssh2_pkt_addstring("window-change");
5623 ssh2_pkt_addbool(0);
5624 ssh2_pkt_adduint32(cols);
5625 ssh2_pkt_adduint32(rows);
5626 ssh2_pkt_adduint32(0);
5627 ssh2_pkt_adduint32(0);
5628 ssh2_pkt_send();
5629 }
5630 }
5631 break;
374330e2 5632 }
5633}
5634
5635/*
6abbf9e3 5636 * Send Telnet special codes. TS_EOF is useful for `plink', so you
5637 * can send an EOF and collect resulting output (e.g. `plink
5638 * hostname sort').
374330e2 5639 */
32874aea 5640static void ssh_special(Telnet_Special code)
5641{
6abbf9e3 5642 if (code == TS_EOF) {
32874aea 5643 if (ssh_state != SSH_STATE_SESSION) {
5644 /*
5645 * Buffer the EOF in case we are pre-SESSION, so we can
5646 * send it as soon as we reach SESSION.
5647 */
5648 if (code == TS_EOF)
5649 eof_needed = TRUE;
5650 return;
5651 }
5652 if (ssh_version == 1) {
5653 send_packet(SSH1_CMSG_EOF, PKT_END);
5654 } else {
5655 ssh2_pkt_init(SSH2_MSG_CHANNEL_EOF);
5656 ssh2_pkt_adduint32(mainchan->remoteid);
5657 ssh2_pkt_send();
5658 }
5659 logevent("Sent EOF message");
ec55b220 5660 } else if (code == TS_PING) {
32874aea 5661 if (ssh_state == SSH_STATE_CLOSED
5662 || ssh_state == SSH_STATE_PREPACKET) return;
5663 if (ssh_version == 1) {
5664 send_packet(SSH1_MSG_IGNORE, PKT_STR, "", PKT_END);
5665 } else {
5666 ssh2_pkt_init(SSH2_MSG_IGNORE);
5667 ssh2_pkt_addstring_start();
5668 ssh2_pkt_send();
5669 }
6abbf9e3 5670 } else {
32874aea 5671 /* do nothing */
6abbf9e3 5672 }
374330e2 5673}
5674
d74d141c 5675void *new_sock_channel(Socket s)
5676{
5677 struct ssh_channel *c;
5678 c = smalloc(sizeof(struct ssh_channel));
5679
5680 if (c) {
bc240b21 5681 c->remoteid = -1; /* to be set when open confirmed */
d74d141c 5682 c->localid = alloc_channel_id();
5683 c->closes = 0;
bc240b21 5684 c->type = CHAN_SOCKDATA_DORMANT;/* identify channel type */
d74d141c 5685 c->u.pfd.s = s;
5686 add234(ssh_channels, c);
5687 }
5688 return c;
5689}
5690
5471d09a 5691/*
5692 * This is called when stdout/stderr (the entity to which
5693 * from_backend sends data) manages to clear some backlog.
5694 */
5695void ssh_unthrottle(int bufsize)
5696{
5697 if (ssh_version == 1) {
90347b95 5698 if (ssh1_stdout_throttling && bufsize < SSH1_BUFFER_LIMIT) {
5471d09a 5699 ssh1_stdout_throttling = 0;
5700 ssh1_throttle(-1);
5701 }
5702 } else {
5703 if (mainchan && mainchan->closes == 0)
5704 ssh2_set_window(mainchan, OUR_V2_WINSIZE - bufsize);
5705 }
5706}
5707
d74d141c 5708void ssh_send_port_open(void *channel, char *hostname, int port, char *org)
5709{
5710 struct ssh_channel *c = (struct ssh_channel *)channel;
5711 char buf[1024];
5712
5713 sprintf(buf, "Opening forwarded connection to %.512s:%d", hostname, port);
5714 logevent(buf);
5715
bc240b21 5716 if (ssh_version == 1) {
5717 send_packet(SSH1_MSG_PORT_OPEN,
5718 PKT_INT, c->localid,
5719 PKT_STR, hostname,
5720 PKT_INT, port,
5721 //PKT_STR, <org:orgport>,
5722 PKT_END);
5723 } else {
5724 ssh2_pkt_init(SSH2_MSG_CHANNEL_OPEN);
5725 ssh2_pkt_addstring("direct-tcpip");
5726 ssh2_pkt_adduint32(c->localid);
5471d09a 5727 c->v.v2.locwindow = OUR_V2_WINSIZE;
5728 ssh2_pkt_adduint32(c->v.v2.locwindow);/* our window size */
bc240b21 5729 ssh2_pkt_adduint32(0x4000UL); /* our max pkt size */
5730 ssh2_pkt_addstring(hostname);
5731 ssh2_pkt_adduint32(port);
5732 /*
5733 * We make up values for the originator data; partly it's
5734 * too much hassle to keep track, and partly I'm not
5735 * convinced the server should be told details like that
5736 * about my local network configuration.
5737 */
5738 ssh2_pkt_addstring("client-side-connection");
5739 ssh2_pkt_adduint32(0);
5740 ssh2_pkt_send();
5741 }
d74d141c 5742}
5743
5744
32874aea 5745static Socket ssh_socket(void)
5746{
5747 return s;
5748}
8ccc75b0 5749
32874aea 5750static int ssh_sendok(void)
5751{
5752 return ssh_send_ok;
5753}
fb09bf1c 5754
32874aea 5755static int ssh_ldisc(int option)
5756{
5757 if (option == LD_ECHO)
5758 return ssh_echoing;
5759 if (option == LD_EDIT)
5760 return ssh_editing;
0965bee0 5761 return FALSE;
5762}
5763
d8d6c7e5 5764static int ssh_return_exitcode(void)
5765{
5766 return ssh_exitcode;
5767}
5768
374330e2 5769Backend ssh_backend = {
5770 ssh_init,
374330e2 5771 ssh_send,
5471d09a 5772 ssh_sendbuffer,
374330e2 5773 ssh_size,
4017be6d 5774 ssh_special,
8ccc75b0 5775 ssh_socket,
d8d6c7e5 5776 ssh_return_exitcode,
97db3be4 5777 ssh_sendok,
0965bee0 5778 ssh_ldisc,
5471d09a 5779 ssh_unthrottle,
97db3be4 5780 22
bc240b21 5781};
Local modifications for Simon Tatham's `PuTTY' SSH client and terminal emulator