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8efc0c15 | 1 | /* |
5260325f | 2 | * Author: Tatu Ylonen <ylo@cs.hut.fi> |
5260325f | 3 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland |
4 | * All rights reserved | |
5260325f | 5 | * This file contains functions for generic socket connection forwarding. |
6 | * There is also code for initiating connection forwarding for X11 connections, | |
7 | * arbitrary tcp/ip connections, and the authentication agent connection. | |
6ae2364d | 8 | * |
bcbf86ec | 9 | * As far as I am concerned, the code I have written for this software |
10 | * can be used freely for any purpose. Any derived versions of this | |
11 | * software must be clearly marked as such, and if the derived work is | |
12 | * incompatible with the protocol description in the RFC file, it must be | |
13 | * called by a name other than "ssh" or "Secure Shell". | |
14 | * | |
7e7327a1 | 15 | * SSH2 support added by Markus Friedl. |
8341f420 | 16 | * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved. |
bcbf86ec | 17 | * Copyright (c) 1999 Dug Song. All rights reserved. |
18 | * Copyright (c) 1999 Theo de Raadt. All rights reserved. | |
19 | * | |
20 | * Redistribution and use in source and binary forms, with or without | |
21 | * modification, are permitted provided that the following conditions | |
22 | * are met: | |
23 | * 1. Redistributions of source code must retain the above copyright | |
24 | * notice, this list of conditions and the following disclaimer. | |
25 | * 2. Redistributions in binary form must reproduce the above copyright | |
26 | * notice, this list of conditions and the following disclaimer in the | |
27 | * documentation and/or other materials provided with the distribution. | |
28 | * | |
29 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR | |
30 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES | |
31 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. | |
32 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, | |
33 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | |
34 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | |
35 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | |
36 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
37 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | |
38 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
5260325f | 39 | */ |
8efc0c15 | 40 | |
41 | #include "includes.h" | |
70bef40e | 42 | RCSID("$OpenBSD: channels.c,v 1.159 2002/01/14 13:55:55 markus Exp $"); |
8efc0c15 | 43 | |
44 | #include "ssh.h" | |
42f11eb2 | 45 | #include "ssh1.h" |
46 | #include "ssh2.h" | |
8efc0c15 | 47 | #include "packet.h" |
48 | #include "xmalloc.h" | |
8efc0c15 | 49 | #include "uidswap.h" |
42f11eb2 | 50 | #include "log.h" |
51 | #include "misc.h" | |
8efc0c15 | 52 | #include "channels.h" |
8efc0c15 | 53 | #include "compat.h" |
42f11eb2 | 54 | #include "canohost.h" |
4c8722d9 | 55 | #include "key.h" |
56 | #include "authfd.h" | |
805e659f | 57 | #include "pathnames.h" |
7e7327a1 | 58 | |
8efc0c15 | 59 | |
8e7895b8 | 60 | /* -- channel core */ |
8efc0c15 | 61 | |
aa3378df | 62 | /* |
63 | * Pointer to an array containing all allocated channels. The array is | |
64 | * dynamically extended as needed. | |
65 | */ | |
719fc62f | 66 | static Channel **channels = NULL; |
8efc0c15 | 67 | |
aa3378df | 68 | /* |
69 | * Size of the channel array. All slots of the array must always be | |
719fc62f | 70 | * initialized (at least the type field); unused slots set to NULL |
aa3378df | 71 | */ |
8efc0c15 | 72 | static int channels_alloc = 0; |
73 | ||
aa3378df | 74 | /* |
75 | * Maximum file descriptor value used in any of the channels. This is | |
719fc62f | 76 | * updated in channel_new. |
aa3378df | 77 | */ |
39929cdb | 78 | static int channel_max_fd = 0; |
8efc0c15 | 79 | |
8efc0c15 | 80 | |
8e7895b8 | 81 | /* -- tcp forwarding */ |
8efc0c15 | 82 | |
aa3378df | 83 | /* |
84 | * Data structure for storing which hosts are permitted for forward requests. | |
85 | * The local sides of any remote forwards are stored in this array to prevent | |
86 | * a corrupt remote server from accessing arbitrary TCP/IP ports on our local | |
87 | * network (which might be behind a firewall). | |
88 | */ | |
5260325f | 89 | typedef struct { |
7368a6c8 | 90 | char *host_to_connect; /* Connect to 'host'. */ |
91 | u_short port_to_connect; /* Connect to 'port'. */ | |
92 | u_short listen_port; /* Remote side should listen port number. */ | |
8efc0c15 | 93 | } ForwardPermission; |
94 | ||
95 | /* List of all permitted host/port pairs to connect. */ | |
96 | static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION]; | |
8e7895b8 | 97 | |
8efc0c15 | 98 | /* Number of permitted host/port pairs in the array. */ |
99 | static int num_permitted_opens = 0; | |
aa3378df | 100 | /* |
101 | * If this is true, all opens are permitted. This is the case on the server | |
102 | * on which we have to trust the client anyway, and the user could do | |
103 | * anything after logging in anyway. | |
104 | */ | |
8efc0c15 | 105 | static int all_opens_permitted = 0; |
106 | ||
8efc0c15 | 107 | |
8e7895b8 | 108 | /* -- X11 forwarding */ |
42f11eb2 | 109 | |
8e7895b8 | 110 | /* Maximum number of fake X11 displays to try. */ |
111 | #define MAX_DISPLAYS 1000 | |
0490e609 | 112 | |
8e7895b8 | 113 | /* Saved X11 authentication protocol name. */ |
114 | static char *x11_saved_proto = NULL; | |
8efc0c15 | 115 | |
8e7895b8 | 116 | /* Saved X11 authentication data. This is the real data. */ |
117 | static char *x11_saved_data = NULL; | |
118 | static u_int x11_saved_data_len = 0; | |
119 | ||
120 | /* | |
121 | * Fake X11 authentication data. This is what the server will be sending us; | |
122 | * we should replace any occurrences of this by the real data. | |
123 | */ | |
124 | static char *x11_fake_data = NULL; | |
125 | static u_int x11_fake_data_len; | |
126 | ||
127 | ||
128 | /* -- agent forwarding */ | |
8efc0c15 | 129 | |
8e7895b8 | 130 | #define NUM_SOCKS 10 |
131 | ||
132 | /* Name and directory of socket for authentication agent forwarding. */ | |
133 | static char *auth_sock_name = NULL; | |
134 | static char *auth_sock_dir = NULL; | |
135 | ||
8e7895b8 | 136 | /* AF_UNSPEC or AF_INET or AF_INET6 */ |
5e4a7219 | 137 | static int IPv4or6 = AF_UNSPEC; |
8e7895b8 | 138 | |
139 | /* helper */ | |
396c147e | 140 | static void port_open_helper(Channel *c, char *rtype); |
8e7895b8 | 141 | |
142 | /* -- channel core */ | |
7368a6c8 | 143 | |
144 | Channel * | |
145 | channel_lookup(int id) | |
146 | { | |
147 | Channel *c; | |
719fc62f | 148 | |
3e98362e | 149 | if (id < 0 || id > channels_alloc) { |
7368a6c8 | 150 | log("channel_lookup: %d: bad id", id); |
151 | return NULL; | |
152 | } | |
719fc62f | 153 | c = channels[id]; |
154 | if (c == NULL) { | |
7368a6c8 | 155 | log("channel_lookup: %d: bad id: channel free", id); |
156 | return NULL; | |
157 | } | |
158 | return c; | |
159 | } | |
160 | ||
aa3378df | 161 | /* |
1d1ffb87 | 162 | * Register filedescriptors for a channel, used when allocating a channel or |
0fbe8c74 | 163 | * when the channel consumer/producer is ready, e.g. shell exec'd |
aa3378df | 164 | */ |
8efc0c15 | 165 | |
396c147e | 166 | static void |
a22aff1f | 167 | channel_register_fds(Channel *c, int rfd, int wfd, int efd, |
168 | int extusage, int nonblock) | |
8efc0c15 | 169 | { |
5260325f | 170 | /* Update the maximum file descriptor value. */ |
39929cdb | 171 | channel_max_fd = MAX(channel_max_fd, rfd); |
172 | channel_max_fd = MAX(channel_max_fd, wfd); | |
173 | channel_max_fd = MAX(channel_max_fd, efd); | |
174 | ||
aa3378df | 175 | /* XXX set close-on-exec -markus */ |
1d1ffb87 | 176 | |
0fbe8c74 | 177 | c->rfd = rfd; |
178 | c->wfd = wfd; | |
179 | c->sock = (rfd == wfd) ? rfd : -1; | |
180 | c->efd = efd; | |
181 | c->extended_usage = extusage; | |
a22aff1f | 182 | |
0ae4fe1d | 183 | /* XXX ugly hack: nonblock is only set by the server */ |
184 | if (nonblock && isatty(c->rfd)) { | |
94dfb550 | 185 | debug("channel %d: rfd %d isatty", c->self, c->rfd); |
0ae4fe1d | 186 | c->isatty = 1; |
187 | if (!isatty(c->wfd)) { | |
94dfb550 | 188 | error("channel %d: wfd %d is not a tty?", |
0ae4fe1d | 189 | c->self, c->wfd); |
190 | } | |
191 | } else { | |
192 | c->isatty = 0; | |
193 | } | |
194 | ||
a22aff1f | 195 | /* enable nonblocking mode */ |
196 | if (nonblock) { | |
197 | if (rfd != -1) | |
198 | set_nonblock(rfd); | |
199 | if (wfd != -1) | |
200 | set_nonblock(wfd); | |
201 | if (efd != -1) | |
202 | set_nonblock(efd); | |
203 | } | |
0fbe8c74 | 204 | } |
205 | ||
206 | /* | |
207 | * Allocate a new channel object and set its type and socket. This will cause | |
208 | * remote_name to be freed. | |
209 | */ | |
210 | ||
719fc62f | 211 | Channel * |
0fbe8c74 | 212 | channel_new(char *ctype, int type, int rfd, int wfd, int efd, |
a22aff1f | 213 | int window, int maxpack, int extusage, char *remote_name, int nonblock) |
0fbe8c74 | 214 | { |
215 | int i, found; | |
216 | Channel *c; | |
5260325f | 217 | |
218 | /* Do initial allocation if this is the first call. */ | |
219 | if (channels_alloc == 0) { | |
220 | channels_alloc = 10; | |
719fc62f | 221 | channels = xmalloc(channels_alloc * sizeof(Channel *)); |
5260325f | 222 | for (i = 0; i < channels_alloc; i++) |
719fc62f | 223 | channels[i] = NULL; |
d6746a0b | 224 | fatal_add_cleanup((void (*) (void *)) channel_free_all, NULL); |
5260325f | 225 | } |
226 | /* Try to find a free slot where to put the new channel. */ | |
227 | for (found = -1, i = 0; i < channels_alloc; i++) | |
719fc62f | 228 | if (channels[i] == NULL) { |
5260325f | 229 | /* Found a free slot. */ |
230 | found = i; | |
231 | break; | |
232 | } | |
233 | if (found == -1) { | |
aa3378df | 234 | /* There are no free slots. Take last+1 slot and expand the array. */ |
5260325f | 235 | found = channels_alloc; |
236 | channels_alloc += 10; | |
de273eef | 237 | debug2("channel: expanding %d", channels_alloc); |
719fc62f | 238 | channels = xrealloc(channels, channels_alloc * sizeof(Channel *)); |
5260325f | 239 | for (i = found; i < channels_alloc; i++) |
719fc62f | 240 | channels[i] = NULL; |
5260325f | 241 | } |
719fc62f | 242 | /* Initialize and return new channel. */ |
243 | c = channels[found] = xmalloc(sizeof(Channel)); | |
639cb8ab | 244 | memset(c, 0, sizeof(Channel)); |
5260325f | 245 | buffer_init(&c->input); |
246 | buffer_init(&c->output); | |
7368a6c8 | 247 | buffer_init(&c->extended); |
70bef40e | 248 | c->ostate = CHAN_OUTPUT_OPEN; |
249 | c->istate = CHAN_INPUT_OPEN; | |
250 | c->flags = 0; | |
a22aff1f | 251 | channel_register_fds(c, rfd, wfd, efd, extusage, nonblock); |
5260325f | 252 | c->self = found; |
253 | c->type = type; | |
7368a6c8 | 254 | c->ctype = ctype; |
0b242b12 | 255 | c->local_window = window; |
256 | c->local_window_max = window; | |
257 | c->local_consumed = 0; | |
258 | c->local_maxpacket = maxpack; | |
5260325f | 259 | c->remote_id = -1; |
260 | c->remote_name = remote_name; | |
7368a6c8 | 261 | c->remote_window = 0; |
262 | c->remote_maxpacket = 0; | |
263 | c->cb_fn = NULL; | |
264 | c->cb_arg = NULL; | |
265 | c->cb_event = 0; | |
a5f82435 | 266 | c->force_drain = 0; |
ac151b18 | 267 | c->single_connection = 0; |
3cf2be58 | 268 | c->detach_user = NULL; |
2e73a022 | 269 | c->input_filter = NULL; |
5260325f | 270 | debug("channel %d: new [%s]", found, remote_name); |
719fc62f | 271 | return c; |
7368a6c8 | 272 | } |
8efc0c15 | 273 | |
489aa2e9 | 274 | static int |
275 | channel_find_maxfd(void) | |
276 | { | |
277 | int i, max = 0; | |
278 | Channel *c; | |
279 | ||
280 | for (i = 0; i < channels_alloc; i++) { | |
281 | c = channels[i]; | |
282 | if (c != NULL) { | |
283 | max = MAX(max, c->rfd); | |
284 | max = MAX(max, c->wfd); | |
285 | max = MAX(max, c->efd); | |
286 | } | |
287 | } | |
288 | return max; | |
289 | } | |
290 | ||
291 | int | |
292 | channel_close_fd(int *fdp) | |
293 | { | |
294 | int ret = 0, fd = *fdp; | |
295 | ||
296 | if (fd != -1) { | |
297 | ret = close(fd); | |
298 | *fdp = -1; | |
299 | if (fd == channel_max_fd) | |
300 | channel_max_fd = channel_find_maxfd(); | |
301 | } | |
302 | return ret; | |
303 | } | |
304 | ||
0fbe8c74 | 305 | /* Close all channel fd/socket. */ |
306 | ||
396c147e | 307 | static void |
0fbe8c74 | 308 | channel_close_fds(Channel *c) |
309 | { | |
6fd8622b | 310 | debug3("channel_close_fds: channel %d: r %d w %d e %d", |
311 | c->self, c->rfd, c->wfd, c->efd); | |
312 | ||
489aa2e9 | 313 | channel_close_fd(&c->sock); |
314 | channel_close_fd(&c->rfd); | |
315 | channel_close_fd(&c->wfd); | |
316 | channel_close_fd(&c->efd); | |
0fbe8c74 | 317 | } |
318 | ||
8e7895b8 | 319 | /* Free the channel and close its fd/socket. */ |
320 | ||
321 | void | |
322 | channel_free(Channel *c) | |
323 | { | |
324 | char *s; | |
325 | int i, n; | |
326 | ||
327 | for (n = 0, i = 0; i < channels_alloc; i++) | |
328 | if (channels[i]) | |
329 | n++; | |
330 | debug("channel_free: channel %d: %s, nchannels %d", c->self, | |
331 | c->remote_name ? c->remote_name : "???", n); | |
332 | ||
333 | s = channel_open_message(); | |
334 | debug3("channel_free: status: %s", s); | |
335 | xfree(s); | |
336 | ||
8e7895b8 | 337 | if (c->sock != -1) |
338 | shutdown(c->sock, SHUT_RDWR); | |
339 | channel_close_fds(c); | |
340 | buffer_free(&c->input); | |
341 | buffer_free(&c->output); | |
342 | buffer_free(&c->extended); | |
343 | if (c->remote_name) { | |
344 | xfree(c->remote_name); | |
345 | c->remote_name = NULL; | |
346 | } | |
347 | channels[c->self] = NULL; | |
348 | xfree(c); | |
349 | } | |
350 | ||
8e7895b8 | 351 | void |
d6746a0b | 352 | channel_free_all(void) |
8e7895b8 | 353 | { |
354 | int i; | |
8e7895b8 | 355 | |
d6746a0b | 356 | for (i = 0; i < channels_alloc; i++) |
357 | if (channels[i] != NULL) | |
358 | channel_free(channels[i]); | |
8e7895b8 | 359 | } |
360 | ||
361 | /* | |
362 | * Closes the sockets/fds of all channels. This is used to close extra file | |
363 | * descriptors after a fork. | |
364 | */ | |
365 | ||
366 | void | |
d5bb9418 | 367 | channel_close_all(void) |
8e7895b8 | 368 | { |
369 | int i; | |
370 | ||
371 | for (i = 0; i < channels_alloc; i++) | |
372 | if (channels[i] != NULL) | |
373 | channel_close_fds(channels[i]); | |
374 | } | |
375 | ||
3cf2be58 | 376 | /* |
377 | * Stop listening to channels. | |
378 | */ | |
379 | ||
380 | void | |
381 | channel_stop_listening(void) | |
382 | { | |
383 | int i; | |
384 | Channel *c; | |
385 | ||
386 | for (i = 0; i < channels_alloc; i++) { | |
387 | c = channels[i]; | |
388 | if (c != NULL) { | |
389 | switch (c->type) { | |
390 | case SSH_CHANNEL_AUTH_SOCKET: | |
391 | case SSH_CHANNEL_PORT_LISTENER: | |
392 | case SSH_CHANNEL_RPORT_LISTENER: | |
393 | case SSH_CHANNEL_X11_LISTENER: | |
489aa2e9 | 394 | channel_close_fd(&c->sock); |
3cf2be58 | 395 | channel_free(c); |
396 | break; | |
397 | } | |
398 | } | |
399 | } | |
400 | } | |
401 | ||
8e7895b8 | 402 | /* |
403 | * Returns true if no channel has too much buffered data, and false if one or | |
404 | * more channel is overfull. | |
405 | */ | |
406 | ||
407 | int | |
d5bb9418 | 408 | channel_not_very_much_buffered_data(void) |
8e7895b8 | 409 | { |
410 | u_int i; | |
411 | Channel *c; | |
412 | ||
413 | for (i = 0; i < channels_alloc; i++) { | |
414 | c = channels[i]; | |
415 | if (c != NULL && c->type == SSH_CHANNEL_OPEN) { | |
0c139bd1 | 416 | #if 0 |
417 | if (!compat20 && | |
418 | buffer_len(&c->input) > packet_get_maxsize()) { | |
8e7895b8 | 419 | debug("channel %d: big input buffer %d", |
420 | c->self, buffer_len(&c->input)); | |
421 | return 0; | |
422 | } | |
0c139bd1 | 423 | #endif |
8e7895b8 | 424 | if (buffer_len(&c->output) > packet_get_maxsize()) { |
0c139bd1 | 425 | debug("channel %d: big output buffer %d > %d", |
426 | c->self, buffer_len(&c->output), | |
427 | packet_get_maxsize()); | |
8e7895b8 | 428 | return 0; |
429 | } | |
430 | } | |
431 | } | |
432 | return 1; | |
433 | } | |
434 | ||
435 | /* Returns true if any channel is still open. */ | |
436 | ||
437 | int | |
d5bb9418 | 438 | channel_still_open(void) |
8e7895b8 | 439 | { |
440 | int i; | |
441 | Channel *c; | |
442 | ||
443 | for (i = 0; i < channels_alloc; i++) { | |
444 | c = channels[i]; | |
445 | if (c == NULL) | |
446 | continue; | |
447 | switch (c->type) { | |
448 | case SSH_CHANNEL_X11_LISTENER: | |
449 | case SSH_CHANNEL_PORT_LISTENER: | |
450 | case SSH_CHANNEL_RPORT_LISTENER: | |
451 | case SSH_CHANNEL_CLOSED: | |
452 | case SSH_CHANNEL_AUTH_SOCKET: | |
453 | case SSH_CHANNEL_DYNAMIC: | |
454 | case SSH_CHANNEL_CONNECTING: | |
455 | case SSH_CHANNEL_ZOMBIE: | |
456 | continue; | |
457 | case SSH_CHANNEL_LARVAL: | |
458 | if (!compat20) | |
459 | fatal("cannot happen: SSH_CHANNEL_LARVAL"); | |
460 | continue; | |
461 | case SSH_CHANNEL_OPENING: | |
462 | case SSH_CHANNEL_OPEN: | |
463 | case SSH_CHANNEL_X11_OPEN: | |
464 | return 1; | |
465 | case SSH_CHANNEL_INPUT_DRAINING: | |
466 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
467 | if (!compat13) | |
468 | fatal("cannot happen: OUT_DRAIN"); | |
469 | return 1; | |
470 | default: | |
471 | fatal("channel_still_open: bad channel type %d", c->type); | |
472 | /* NOTREACHED */ | |
473 | } | |
474 | } | |
475 | return 0; | |
476 | } | |
477 | ||
478 | /* Returns the id of an open channel suitable for keepaliving */ | |
479 | ||
480 | int | |
d5bb9418 | 481 | channel_find_open(void) |
8e7895b8 | 482 | { |
483 | int i; | |
484 | Channel *c; | |
485 | ||
486 | for (i = 0; i < channels_alloc; i++) { | |
487 | c = channels[i]; | |
488 | if (c == NULL) | |
489 | continue; | |
490 | switch (c->type) { | |
491 | case SSH_CHANNEL_CLOSED: | |
492 | case SSH_CHANNEL_DYNAMIC: | |
493 | case SSH_CHANNEL_X11_LISTENER: | |
494 | case SSH_CHANNEL_PORT_LISTENER: | |
495 | case SSH_CHANNEL_RPORT_LISTENER: | |
496 | case SSH_CHANNEL_OPENING: | |
497 | case SSH_CHANNEL_CONNECTING: | |
498 | case SSH_CHANNEL_ZOMBIE: | |
499 | continue; | |
500 | case SSH_CHANNEL_LARVAL: | |
501 | case SSH_CHANNEL_AUTH_SOCKET: | |
502 | case SSH_CHANNEL_OPEN: | |
503 | case SSH_CHANNEL_X11_OPEN: | |
504 | return i; | |
505 | case SSH_CHANNEL_INPUT_DRAINING: | |
506 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
507 | if (!compat13) | |
508 | fatal("cannot happen: OUT_DRAIN"); | |
509 | return i; | |
510 | default: | |
511 | fatal("channel_find_open: bad channel type %d", c->type); | |
512 | /* NOTREACHED */ | |
513 | } | |
514 | } | |
515 | return -1; | |
516 | } | |
517 | ||
518 | ||
519 | /* | |
520 | * Returns a message describing the currently open forwarded connections, | |
521 | * suitable for sending to the client. The message contains crlf pairs for | |
522 | * newlines. | |
523 | */ | |
524 | ||
525 | char * | |
d5bb9418 | 526 | channel_open_message(void) |
8e7895b8 | 527 | { |
528 | Buffer buffer; | |
529 | Channel *c; | |
530 | char buf[1024], *cp; | |
531 | int i; | |
532 | ||
533 | buffer_init(&buffer); | |
534 | snprintf(buf, sizeof buf, "The following connections are open:\r\n"); | |
535 | buffer_append(&buffer, buf, strlen(buf)); | |
536 | for (i = 0; i < channels_alloc; i++) { | |
537 | c = channels[i]; | |
538 | if (c == NULL) | |
539 | continue; | |
540 | switch (c->type) { | |
541 | case SSH_CHANNEL_X11_LISTENER: | |
542 | case SSH_CHANNEL_PORT_LISTENER: | |
543 | case SSH_CHANNEL_RPORT_LISTENER: | |
544 | case SSH_CHANNEL_CLOSED: | |
545 | case SSH_CHANNEL_AUTH_SOCKET: | |
546 | case SSH_CHANNEL_ZOMBIE: | |
547 | continue; | |
548 | case SSH_CHANNEL_LARVAL: | |
549 | case SSH_CHANNEL_OPENING: | |
550 | case SSH_CHANNEL_CONNECTING: | |
551 | case SSH_CHANNEL_DYNAMIC: | |
552 | case SSH_CHANNEL_OPEN: | |
553 | case SSH_CHANNEL_X11_OPEN: | |
554 | case SSH_CHANNEL_INPUT_DRAINING: | |
555 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
556 | snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n", | |
557 | c->self, c->remote_name, | |
558 | c->type, c->remote_id, | |
559 | c->istate, buffer_len(&c->input), | |
560 | c->ostate, buffer_len(&c->output), | |
561 | c->rfd, c->wfd); | |
562 | buffer_append(&buffer, buf, strlen(buf)); | |
563 | continue; | |
564 | default: | |
565 | fatal("channel_open_message: bad channel type %d", c->type); | |
566 | /* NOTREACHED */ | |
567 | } | |
568 | } | |
569 | buffer_append(&buffer, "\0", 1); | |
570 | cp = xstrdup(buffer_ptr(&buffer)); | |
571 | buffer_free(&buffer); | |
572 | return cp; | |
573 | } | |
574 | ||
575 | void | |
576 | channel_send_open(int id) | |
577 | { | |
578 | Channel *c = channel_lookup(id); | |
579 | if (c == NULL) { | |
580 | log("channel_send_open: %d: bad id", id); | |
581 | return; | |
582 | } | |
583 | debug("send channel open %d", id); | |
584 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
585 | packet_put_cstring(c->ctype); | |
586 | packet_put_int(c->self); | |
587 | packet_put_int(c->local_window); | |
588 | packet_put_int(c->local_maxpacket); | |
589 | packet_send(); | |
590 | } | |
591 | ||
592 | void | |
593 | channel_request(int id, char *service, int wantconfirm) | |
594 | { | |
595 | channel_request_start(id, service, wantconfirm); | |
596 | packet_send(); | |
597 | debug("channel request %d: %s", id, service) ; | |
598 | } | |
599 | void | |
600 | channel_request_start(int id, char *service, int wantconfirm) | |
601 | { | |
602 | Channel *c = channel_lookup(id); | |
603 | if (c == NULL) { | |
604 | log("channel_request: %d: bad id", id); | |
605 | return; | |
606 | } | |
607 | packet_start(SSH2_MSG_CHANNEL_REQUEST); | |
608 | packet_put_int(c->remote_id); | |
609 | packet_put_cstring(service); | |
610 | packet_put_char(wantconfirm); | |
611 | } | |
612 | void | |
613 | channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg) | |
614 | { | |
615 | Channel *c = channel_lookup(id); | |
616 | if (c == NULL) { | |
617 | log("channel_register_callback: %d: bad id", id); | |
618 | return; | |
619 | } | |
620 | c->cb_event = mtype; | |
621 | c->cb_fn = fn; | |
622 | c->cb_arg = arg; | |
623 | } | |
624 | void | |
625 | channel_register_cleanup(int id, channel_callback_fn *fn) | |
626 | { | |
627 | Channel *c = channel_lookup(id); | |
628 | if (c == NULL) { | |
629 | log("channel_register_cleanup: %d: bad id", id); | |
630 | return; | |
631 | } | |
3cf2be58 | 632 | c->detach_user = fn; |
8e7895b8 | 633 | } |
634 | void | |
635 | channel_cancel_cleanup(int id) | |
636 | { | |
637 | Channel *c = channel_lookup(id); | |
638 | if (c == NULL) { | |
639 | log("channel_cancel_cleanup: %d: bad id", id); | |
640 | return; | |
641 | } | |
3cf2be58 | 642 | c->detach_user = NULL; |
8e7895b8 | 643 | } |
644 | void | |
645 | channel_register_filter(int id, channel_filter_fn *fn) | |
646 | { | |
647 | Channel *c = channel_lookup(id); | |
648 | if (c == NULL) { | |
649 | log("channel_register_filter: %d: bad id", id); | |
650 | return; | |
651 | } | |
652 | c->input_filter = fn; | |
653 | } | |
654 | ||
6ae2364d | 655 | void |
8e7895b8 | 656 | channel_set_fds(int id, int rfd, int wfd, int efd, |
657 | int extusage, int nonblock) | |
8efc0c15 | 658 | { |
8e7895b8 | 659 | Channel *c = channel_lookup(id); |
660 | if (c == NULL || c->type != SSH_CHANNEL_LARVAL) | |
661 | fatal("channel_activate for non-larval channel %d.", id); | |
662 | channel_register_fds(c, rfd, wfd, efd, extusage, nonblock); | |
663 | c->type = SSH_CHANNEL_OPEN; | |
664 | /* XXX window size? */ | |
665 | c->local_window = c->local_window_max = c->local_maxpacket * 2; | |
666 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); | |
667 | packet_put_int(c->remote_id); | |
668 | packet_put_int(c->local_window); | |
669 | packet_send(); | |
8efc0c15 | 670 | } |
671 | ||
aa3378df | 672 | /* |
7368a6c8 | 673 | * 'channel_pre*' are called just before select() to add any bits relevant to |
674 | * channels in the select bitmasks. | |
aa3378df | 675 | */ |
7368a6c8 | 676 | /* |
677 | * 'channel_post*': perform any appropriate operations for channels which | |
678 | * have events pending. | |
679 | */ | |
680 | typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset); | |
681 | chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE]; | |
682 | chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE]; | |
8efc0c15 | 683 | |
396c147e | 684 | static void |
7368a6c8 | 685 | channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset) |
8efc0c15 | 686 | { |
7368a6c8 | 687 | FD_SET(c->sock, readset); |
688 | } | |
5260325f | 689 | |
396c147e | 690 | static void |
97fb6912 | 691 | channel_pre_connecting(Channel *c, fd_set * readset, fd_set * writeset) |
692 | { | |
693 | debug3("channel %d: waiting for connection", c->self); | |
694 | FD_SET(c->sock, writeset); | |
695 | } | |
696 | ||
396c147e | 697 | static void |
7368a6c8 | 698 | channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset) |
699 | { | |
700 | if (buffer_len(&c->input) < packet_get_maxsize()) | |
701 | FD_SET(c->sock, readset); | |
702 | if (buffer_len(&c->output) > 0) | |
703 | FD_SET(c->sock, writeset); | |
704 | } | |
5260325f | 705 | |
396c147e | 706 | static void |
0c0738d5 | 707 | channel_pre_open(Channel *c, fd_set * readset, fd_set * writeset) |
7368a6c8 | 708 | { |
0c0738d5 | 709 | u_int limit = compat20 ? c->remote_window : packet_get_maxsize(); |
5260325f | 710 | |
7e7327a1 | 711 | if (c->istate == CHAN_INPUT_OPEN && |
0c0738d5 | 712 | limit > 0 && |
713 | buffer_len(&c->input) < limit) | |
7e7327a1 | 714 | FD_SET(c->rfd, readset); |
715 | if (c->ostate == CHAN_OUTPUT_OPEN || | |
716 | c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
717 | if (buffer_len(&c->output) > 0) { | |
718 | FD_SET(c->wfd, writeset); | |
719 | } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
720 | chan_obuf_empty(c); | |
721 | } | |
722 | } | |
723 | /** XXX check close conditions, too */ | |
0c0738d5 | 724 | if (compat20 && c->efd != -1) { |
7e7327a1 | 725 | if (c->extended_usage == CHAN_EXTENDED_WRITE && |
726 | buffer_len(&c->extended) > 0) | |
727 | FD_SET(c->efd, writeset); | |
728 | else if (c->extended_usage == CHAN_EXTENDED_READ && | |
729 | buffer_len(&c->extended) < c->remote_window) | |
730 | FD_SET(c->efd, readset); | |
731 | } | |
732 | } | |
733 | ||
396c147e | 734 | static void |
7368a6c8 | 735 | channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset) |
736 | { | |
737 | if (buffer_len(&c->input) == 0) { | |
738 | packet_start(SSH_MSG_CHANNEL_CLOSE); | |
739 | packet_put_int(c->remote_id); | |
740 | packet_send(); | |
741 | c->type = SSH_CHANNEL_CLOSED; | |
070adba2 | 742 | debug("channel %d: closing after input drain.", c->self); |
7368a6c8 | 743 | } |
744 | } | |
5260325f | 745 | |
396c147e | 746 | static void |
7368a6c8 | 747 | channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset) |
748 | { | |
749 | if (buffer_len(&c->output) == 0) | |
719fc62f | 750 | chan_mark_dead(c); |
6ae2364d | 751 | else |
7368a6c8 | 752 | FD_SET(c->sock, writeset); |
753 | } | |
5260325f | 754 | |
7368a6c8 | 755 | /* |
756 | * This is a special state for X11 authentication spoofing. An opened X11 | |
757 | * connection (when authentication spoofing is being done) remains in this | |
758 | * state until the first packet has been completely read. The authentication | |
759 | * data in that packet is then substituted by the real data if it matches the | |
760 | * fake data, and the channel is put into normal mode. | |
0b242b12 | 761 | * XXX All this happens at the client side. |
8e7895b8 | 762 | * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok |
7368a6c8 | 763 | */ |
396c147e | 764 | static int |
8e7895b8 | 765 | x11_open_helper(Buffer *b) |
7368a6c8 | 766 | { |
1e3b8b07 | 767 | u_char *ucp; |
768 | u_int proto_len, data_len; | |
5260325f | 769 | |
7368a6c8 | 770 | /* Check if the fixed size part of the packet is in buffer. */ |
8e7895b8 | 771 | if (buffer_len(b) < 12) |
7368a6c8 | 772 | return 0; |
773 | ||
774 | /* Parse the lengths of variable-length fields. */ | |
20905a8e | 775 | ucp = buffer_ptr(b); |
7368a6c8 | 776 | if (ucp[0] == 0x42) { /* Byte order MSB first. */ |
777 | proto_len = 256 * ucp[6] + ucp[7]; | |
778 | data_len = 256 * ucp[8] + ucp[9]; | |
779 | } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */ | |
780 | proto_len = ucp[6] + 256 * ucp[7]; | |
781 | data_len = ucp[8] + 256 * ucp[9]; | |
782 | } else { | |
783 | debug("Initial X11 packet contains bad byte order byte: 0x%x", | |
184eed6a | 784 | ucp[0]); |
7368a6c8 | 785 | return -1; |
786 | } | |
5260325f | 787 | |
7368a6c8 | 788 | /* Check if the whole packet is in buffer. */ |
8e7895b8 | 789 | if (buffer_len(b) < |
7368a6c8 | 790 | 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3)) |
791 | return 0; | |
5260325f | 792 | |
7368a6c8 | 793 | /* Check if authentication protocol matches. */ |
794 | if (proto_len != strlen(x11_saved_proto) || | |
795 | memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) { | |
796 | debug("X11 connection uses different authentication protocol."); | |
797 | return -1; | |
798 | } | |
799 | /* Check if authentication data matches our fake data. */ | |
800 | if (data_len != x11_fake_data_len || | |
801 | memcmp(ucp + 12 + ((proto_len + 3) & ~3), | |
802 | x11_fake_data, x11_fake_data_len) != 0) { | |
803 | debug("X11 auth data does not match fake data."); | |
804 | return -1; | |
805 | } | |
806 | /* Check fake data length */ | |
807 | if (x11_fake_data_len != x11_saved_data_len) { | |
808 | error("X11 fake_data_len %d != saved_data_len %d", | |
809 | x11_fake_data_len, x11_saved_data_len); | |
810 | return -1; | |
811 | } | |
812 | /* | |
813 | * Received authentication protocol and data match | |
814 | * our fake data. Substitute the fake data with real | |
815 | * data. | |
816 | */ | |
817 | memcpy(ucp + 12 + ((proto_len + 3) & ~3), | |
818 | x11_saved_data, x11_saved_data_len); | |
819 | return 1; | |
820 | } | |
5260325f | 821 | |
396c147e | 822 | static void |
7368a6c8 | 823 | channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset) |
824 | { | |
8e7895b8 | 825 | int ret = x11_open_helper(&c->output); |
7368a6c8 | 826 | if (ret == 1) { |
827 | /* Start normal processing for the channel. */ | |
828 | c->type = SSH_CHANNEL_OPEN; | |
a8be9f80 | 829 | channel_pre_open_13(c, readset, writeset); |
7368a6c8 | 830 | } else if (ret == -1) { |
831 | /* | |
832 | * We have received an X11 connection that has bad | |
833 | * authentication information. | |
834 | */ | |
54b974dc | 835 | log("X11 connection rejected because of wrong authentication."); |
7368a6c8 | 836 | buffer_clear(&c->input); |
837 | buffer_clear(&c->output); | |
489aa2e9 | 838 | channel_close_fd(&c->sock); |
7368a6c8 | 839 | c->sock = -1; |
840 | c->type = SSH_CHANNEL_CLOSED; | |
841 | packet_start(SSH_MSG_CHANNEL_CLOSE); | |
842 | packet_put_int(c->remote_id); | |
843 | packet_send(); | |
844 | } | |
845 | } | |
5260325f | 846 | |
396c147e | 847 | static void |
0b242b12 | 848 | channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset) |
7368a6c8 | 849 | { |
8e7895b8 | 850 | int ret = x11_open_helper(&c->output); |
a5f82435 | 851 | |
852 | /* c->force_drain = 1; */ | |
853 | ||
7368a6c8 | 854 | if (ret == 1) { |
855 | c->type = SSH_CHANNEL_OPEN; | |
0c0738d5 | 856 | channel_pre_open(c, readset, writeset); |
7368a6c8 | 857 | } else if (ret == -1) { |
8341f420 | 858 | log("X11 connection rejected because of wrong authentication."); |
7368a6c8 | 859 | debug("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate); |
8341f420 | 860 | chan_read_failed(c); |
861 | buffer_clear(&c->input); | |
862 | chan_ibuf_empty(c); | |
863 | buffer_clear(&c->output); | |
864 | /* for proto v1, the peer will send an IEOF */ | |
865 | if (compat20) | |
866 | chan_write_failed(c); | |
867 | else | |
868 | c->type = SSH_CHANNEL_OPEN; | |
7368a6c8 | 869 | debug("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate); |
870 | } | |
871 | } | |
5260325f | 872 | |
28b9cb4d | 873 | /* try to decode a socks4 header */ |
396c147e | 874 | static int |
28b9cb4d | 875 | channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset) |
0490e609 | 876 | { |
877 | u_char *p, *host; | |
53b8fe68 | 878 | int len, have, i, found; |
184eed6a | 879 | char username[256]; |
0490e609 | 880 | struct { |
881 | u_int8_t version; | |
882 | u_int8_t command; | |
883 | u_int16_t dest_port; | |
28b9cb4d | 884 | struct in_addr dest_addr; |
0490e609 | 885 | } s4_req, s4_rsp; |
886 | ||
28b9cb4d | 887 | debug2("channel %d: decode socks4", c->self); |
53b8fe68 | 888 | |
889 | have = buffer_len(&c->input); | |
890 | len = sizeof(s4_req); | |
891 | if (have < len) | |
892 | return 0; | |
893 | p = buffer_ptr(&c->input); | |
894 | for (found = 0, i = len; i < have; i++) { | |
895 | if (p[i] == '\0') { | |
896 | found = 1; | |
897 | break; | |
898 | } | |
899 | if (i > 1024) { | |
900 | /* the peer is probably sending garbage */ | |
901 | debug("channel %d: decode socks4: too long", | |
902 | c->self); | |
903 | return -1; | |
904 | } | |
905 | } | |
906 | if (!found) | |
907 | return 0; | |
0490e609 | 908 | buffer_get(&c->input, (char *)&s4_req.version, 1); |
909 | buffer_get(&c->input, (char *)&s4_req.command, 1); | |
910 | buffer_get(&c->input, (char *)&s4_req.dest_port, 2); | |
28b9cb4d | 911 | buffer_get(&c->input, (char *)&s4_req.dest_addr, 4); |
53b8fe68 | 912 | have = buffer_len(&c->input); |
0490e609 | 913 | p = buffer_ptr(&c->input); |
914 | len = strlen(p); | |
6683b40f | 915 | debug2("channel %d: decode socks4: user %s/%d", c->self, p, len); |
0490e609 | 916 | if (len > have) |
28b9cb4d | 917 | fatal("channel %d: decode socks4: len %d > have %d", |
0490e609 | 918 | c->self, len, have); |
919 | strlcpy(username, p, sizeof(username)); | |
920 | buffer_consume(&c->input, len); | |
921 | buffer_consume(&c->input, 1); /* trailing '\0' */ | |
922 | ||
28b9cb4d | 923 | host = inet_ntoa(s4_req.dest_addr); |
0490e609 | 924 | strlcpy(c->path, host, sizeof(c->path)); |
925 | c->host_port = ntohs(s4_req.dest_port); | |
184eed6a | 926 | |
6683b40f | 927 | debug("channel %d: dynamic request: socks4 host %s port %u command %u", |
928 | c->self, host, c->host_port, s4_req.command); | |
0490e609 | 929 | |
28b9cb4d | 930 | if (s4_req.command != 1) { |
931 | debug("channel %d: cannot handle: socks4 cn %d", | |
932 | c->self, s4_req.command); | |
933 | return -1; | |
0490e609 | 934 | } |
28b9cb4d | 935 | s4_rsp.version = 0; /* vn: 0 for reply */ |
936 | s4_rsp.command = 90; /* cd: req granted */ | |
0490e609 | 937 | s4_rsp.dest_port = 0; /* ignored */ |
28b9cb4d | 938 | s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */ |
0490e609 | 939 | buffer_append(&c->output, (char *)&s4_rsp, sizeof(s4_rsp)); |
28b9cb4d | 940 | return 1; |
0490e609 | 941 | } |
942 | ||
28b9cb4d | 943 | /* dynamic port forwarding */ |
396c147e | 944 | static void |
28b9cb4d | 945 | channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset) |
946 | { | |
947 | u_char *p; | |
948 | int have, ret; | |
949 | ||
950 | have = buffer_len(&c->input); | |
639cb8ab | 951 | c->delayed = 0; |
28b9cb4d | 952 | debug2("channel %d: pre_dynamic: have %d", c->self, have); |
070adba2 | 953 | /* buffer_dump(&c->input); */ |
28b9cb4d | 954 | /* check if the fixed size part of the packet is in buffer. */ |
955 | if (have < 4) { | |
956 | /* need more */ | |
957 | FD_SET(c->sock, readset); | |
958 | return; | |
959 | } | |
960 | /* try to guess the protocol */ | |
961 | p = buffer_ptr(&c->input); | |
962 | switch (p[0]) { | |
6683b40f | 963 | case 0x04: |
964 | ret = channel_decode_socks4(c, readset, writeset); | |
965 | break; | |
28b9cb4d | 966 | default: |
967 | ret = -1; | |
968 | break; | |
969 | } | |
970 | if (ret < 0) { | |
719fc62f | 971 | chan_mark_dead(c); |
28b9cb4d | 972 | } else if (ret == 0) { |
973 | debug2("channel %d: pre_dynamic: need more", c->self); | |
974 | /* need more */ | |
975 | FD_SET(c->sock, readset); | |
976 | } else { | |
977 | /* switch to the next state */ | |
978 | c->type = SSH_CHANNEL_OPENING; | |
979 | port_open_helper(c, "direct-tcpip"); | |
980 | } | |
981 | } | |
0490e609 | 982 | |
7368a6c8 | 983 | /* This is our fake X11 server socket. */ |
396c147e | 984 | static void |
7368a6c8 | 985 | channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset) |
986 | { | |
719fc62f | 987 | Channel *nc; |
7368a6c8 | 988 | struct sockaddr addr; |
d24631c9 | 989 | int newsock, on = 1; |
7368a6c8 | 990 | socklen_t addrlen; |
865ac82e | 991 | char buf[16384], *remote_ipaddr; |
0b242b12 | 992 | int remote_port; |
7368a6c8 | 993 | |
994 | if (FD_ISSET(c->sock, readset)) { | |
995 | debug("X11 connection requested."); | |
996 | addrlen = sizeof(addr); | |
997 | newsock = accept(c->sock, &addr, &addrlen); | |
ac151b18 | 998 | if (c->single_connection) { |
999 | debug("single_connection: closing X11 listener."); | |
1000 | channel_close_fd(&c->sock); | |
1001 | chan_mark_dead(c); | |
1002 | } | |
7368a6c8 | 1003 | if (newsock < 0) { |
1004 | error("accept: %.100s", strerror(errno)); | |
1005 | return; | |
5260325f | 1006 | } |
d24631c9 | 1007 | if (setsockopt(newsock, IPPROTO_TCP, TCP_NODELAY, &on, |
1008 | sizeof on) == -1) | |
1009 | error("setsockopt TCP_NODELAY: %.100s", | |
1010 | strerror(errno)); | |
865ac82e | 1011 | remote_ipaddr = get_peer_ipaddr(newsock); |
0b242b12 | 1012 | remote_port = get_peer_port(newsock); |
7368a6c8 | 1013 | snprintf(buf, sizeof buf, "X11 connection from %.200s port %d", |
865ac82e | 1014 | remote_ipaddr, remote_port); |
0b242b12 | 1015 | |
719fc62f | 1016 | nc = channel_new("accepted x11 socket", |
0b242b12 | 1017 | SSH_CHANNEL_OPENING, newsock, newsock, -1, |
1018 | c->local_window_max, c->local_maxpacket, | |
a22aff1f | 1019 | 0, xstrdup(buf), 1); |
719fc62f | 1020 | if (nc == NULL) { |
1021 | close(newsock); | |
1022 | xfree(remote_ipaddr); | |
1023 | return; | |
1024 | } | |
0b242b12 | 1025 | if (compat20) { |
1026 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
1027 | packet_put_cstring("x11"); | |
719fc62f | 1028 | packet_put_int(nc->self); |
ac151b18 | 1029 | packet_put_int(nc->local_window_max); |
1030 | packet_put_int(nc->local_maxpacket); | |
865ac82e | 1031 | /* originator ipaddr and port */ |
1032 | packet_put_cstring(remote_ipaddr); | |
d0c832f3 | 1033 | if (datafellows & SSH_BUG_X11FWD) { |
1034 | debug("ssh2 x11 bug compat mode"); | |
1035 | } else { | |
1036 | packet_put_int(remote_port); | |
1037 | } | |
0b242b12 | 1038 | packet_send(); |
1039 | } else { | |
1040 | packet_start(SSH_SMSG_X11_OPEN); | |
719fc62f | 1041 | packet_put_int(nc->self); |
8e7895b8 | 1042 | if (packet_get_protocol_flags() & |
1043 | SSH_PROTOFLAG_HOST_IN_FWD_OPEN) | |
449c5ba5 | 1044 | packet_put_cstring(buf); |
0b242b12 | 1045 | packet_send(); |
1046 | } | |
865ac82e | 1047 | xfree(remote_ipaddr); |
8efc0c15 | 1048 | } |
8efc0c15 | 1049 | } |
1050 | ||
396c147e | 1051 | static void |
0490e609 | 1052 | port_open_helper(Channel *c, char *rtype) |
1053 | { | |
1054 | int direct; | |
1055 | char buf[1024]; | |
1056 | char *remote_ipaddr = get_peer_ipaddr(c->sock); | |
1057 | u_short remote_port = get_peer_port(c->sock); | |
1058 | ||
1059 | direct = (strcmp(rtype, "direct-tcpip") == 0); | |
1060 | ||
1061 | snprintf(buf, sizeof buf, | |
1062 | "%s: listening port %d for %.100s port %d, " | |
1063 | "connect from %.200s port %d", | |
1064 | rtype, c->listening_port, c->path, c->host_port, | |
1065 | remote_ipaddr, remote_port); | |
1066 | ||
1067 | xfree(c->remote_name); | |
1068 | c->remote_name = xstrdup(buf); | |
1069 | ||
1070 | if (compat20) { | |
1071 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
1072 | packet_put_cstring(rtype); | |
1073 | packet_put_int(c->self); | |
1074 | packet_put_int(c->local_window_max); | |
1075 | packet_put_int(c->local_maxpacket); | |
1076 | if (direct) { | |
1077 | /* target host, port */ | |
1078 | packet_put_cstring(c->path); | |
1079 | packet_put_int(c->host_port); | |
1080 | } else { | |
1081 | /* listen address, port */ | |
1082 | packet_put_cstring(c->path); | |
1083 | packet_put_int(c->listening_port); | |
1084 | } | |
1085 | /* originator host and port */ | |
1086 | packet_put_cstring(remote_ipaddr); | |
1087 | packet_put_int(remote_port); | |
1088 | packet_send(); | |
1089 | } else { | |
1090 | packet_start(SSH_MSG_PORT_OPEN); | |
1091 | packet_put_int(c->self); | |
1092 | packet_put_cstring(c->path); | |
1093 | packet_put_int(c->host_port); | |
8e7895b8 | 1094 | if (packet_get_protocol_flags() & |
1095 | SSH_PROTOFLAG_HOST_IN_FWD_OPEN) | |
0490e609 | 1096 | packet_put_cstring(c->remote_name); |
1097 | packet_send(); | |
1098 | } | |
1099 | xfree(remote_ipaddr); | |
1100 | } | |
1101 | ||
aa3378df | 1102 | /* |
7368a6c8 | 1103 | * This socket is listening for connections to a forwarded TCP/IP port. |
aa3378df | 1104 | */ |
396c147e | 1105 | static void |
7368a6c8 | 1106 | channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset) |
1107 | { | |
0490e609 | 1108 | Channel *nc; |
7368a6c8 | 1109 | struct sockaddr addr; |
719fc62f | 1110 | int newsock, nextstate; |
7368a6c8 | 1111 | socklen_t addrlen; |
0490e609 | 1112 | char *rtype; |
fa08c86b | 1113 | |
7368a6c8 | 1114 | if (FD_ISSET(c->sock, readset)) { |
1115 | debug("Connection to port %d forwarding " | |
1116 | "to %.100s port %d requested.", | |
1117 | c->listening_port, c->path, c->host_port); | |
0490e609 | 1118 | |
639cb8ab | 1119 | if (c->type == SSH_CHANNEL_RPORT_LISTENER) { |
1120 | nextstate = SSH_CHANNEL_OPENING; | |
1121 | rtype = "forwarded-tcpip"; | |
1122 | } else { | |
1123 | if (c->host_port == 0) { | |
1124 | nextstate = SSH_CHANNEL_DYNAMIC; | |
f3964cb9 | 1125 | rtype = "dynamic-tcpip"; |
639cb8ab | 1126 | } else { |
1127 | nextstate = SSH_CHANNEL_OPENING; | |
1128 | rtype = "direct-tcpip"; | |
1129 | } | |
1130 | } | |
0490e609 | 1131 | |
7368a6c8 | 1132 | addrlen = sizeof(addr); |
1133 | newsock = accept(c->sock, &addr, &addrlen); | |
1134 | if (newsock < 0) { | |
1135 | error("accept: %.100s", strerror(errno)); | |
1136 | return; | |
1137 | } | |
719fc62f | 1138 | nc = channel_new(rtype, |
0490e609 | 1139 | nextstate, newsock, newsock, -1, |
7368a6c8 | 1140 | c->local_window_max, c->local_maxpacket, |
0490e609 | 1141 | 0, xstrdup(rtype), 1); |
0490e609 | 1142 | if (nc == NULL) { |
719fc62f | 1143 | error("channel_post_port_listener: no new channel:"); |
1144 | close(newsock); | |
0490e609 | 1145 | return; |
7368a6c8 | 1146 | } |
0490e609 | 1147 | nc->listening_port = c->listening_port; |
1148 | nc->host_port = c->host_port; | |
1149 | strlcpy(nc->path, c->path, sizeof(nc->path)); | |
1150 | ||
639cb8ab | 1151 | if (nextstate == SSH_CHANNEL_DYNAMIC) { |
1152 | /* | |
1153 | * do not call the channel_post handler until | |
1154 | * this flag has been reset by a pre-handler. | |
1155 | * otherwise the FD_ISSET calls might overflow | |
1156 | */ | |
1157 | nc->delayed = 1; | |
1158 | } else { | |
0490e609 | 1159 | port_open_helper(nc, rtype); |
639cb8ab | 1160 | } |
7368a6c8 | 1161 | } |
1162 | } | |
8efc0c15 | 1163 | |
7368a6c8 | 1164 | /* |
1165 | * This is the authentication agent socket listening for connections from | |
1166 | * clients. | |
1167 | */ | |
396c147e | 1168 | static void |
7368a6c8 | 1169 | channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset) |
8efc0c15 | 1170 | { |
719fc62f | 1171 | Channel *nc; |
8e7895b8 | 1172 | char *name; |
719fc62f | 1173 | int newsock; |
5260325f | 1174 | struct sockaddr addr; |
48e671d5 | 1175 | socklen_t addrlen; |
5260325f | 1176 | |
7368a6c8 | 1177 | if (FD_ISSET(c->sock, readset)) { |
1178 | addrlen = sizeof(addr); | |
1179 | newsock = accept(c->sock, &addr, &addrlen); | |
1180 | if (newsock < 0) { | |
1181 | error("accept from auth socket: %.100s", strerror(errno)); | |
1182 | return; | |
1183 | } | |
8e7895b8 | 1184 | name = xstrdup("accepted auth socket"); |
719fc62f | 1185 | nc = channel_new("accepted auth socket", |
fa08c86b | 1186 | SSH_CHANNEL_OPENING, newsock, newsock, -1, |
1187 | c->local_window_max, c->local_maxpacket, | |
8e7895b8 | 1188 | 0, name, 1); |
719fc62f | 1189 | if (nc == NULL) { |
1190 | error("channel_post_auth_listener: channel_new failed"); | |
8e7895b8 | 1191 | xfree(name); |
719fc62f | 1192 | close(newsock); |
1193 | } | |
fa08c86b | 1194 | if (compat20) { |
1195 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
1196 | packet_put_cstring("auth-agent@openssh.com"); | |
719fc62f | 1197 | packet_put_int(nc->self); |
fa08c86b | 1198 | packet_put_int(c->local_window_max); |
1199 | packet_put_int(c->local_maxpacket); | |
1200 | } else { | |
1201 | packet_start(SSH_SMSG_AGENT_OPEN); | |
719fc62f | 1202 | packet_put_int(nc->self); |
fa08c86b | 1203 | } |
7368a6c8 | 1204 | packet_send(); |
1205 | } | |
1206 | } | |
5260325f | 1207 | |
396c147e | 1208 | static void |
97fb6912 | 1209 | channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset) |
1210 | { | |
d18e0850 | 1211 | int err = 0; |
8ab2cb35 | 1212 | socklen_t sz = sizeof(err); |
d18e0850 | 1213 | |
97fb6912 | 1214 | if (FD_ISSET(c->sock, writeset)) { |
d18e0850 | 1215 | if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, (char *)&err, |
1216 | &sz) < 0) { | |
1217 | err = errno; | |
1218 | error("getsockopt SO_ERROR failed"); | |
1219 | } | |
1220 | if (err == 0) { | |
1221 | debug("channel %d: connected", c->self); | |
1222 | c->type = SSH_CHANNEL_OPEN; | |
1223 | if (compat20) { | |
1224 | packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1225 | packet_put_int(c->remote_id); | |
1226 | packet_put_int(c->self); | |
1227 | packet_put_int(c->local_window); | |
1228 | packet_put_int(c->local_maxpacket); | |
1229 | } else { | |
1230 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1231 | packet_put_int(c->remote_id); | |
1232 | packet_put_int(c->self); | |
1233 | } | |
97fb6912 | 1234 | } else { |
d18e0850 | 1235 | debug("channel %d: not connected: %s", |
1236 | c->self, strerror(err)); | |
1237 | if (compat20) { | |
1238 | packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE); | |
1239 | packet_put_int(c->remote_id); | |
1240 | packet_put_int(SSH2_OPEN_CONNECT_FAILED); | |
1241 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { | |
1242 | packet_put_cstring(strerror(err)); | |
1243 | packet_put_cstring(""); | |
1244 | } | |
97fb6912 | 1245 | } else { |
d18e0850 | 1246 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); |
1247 | packet_put_int(c->remote_id); | |
97fb6912 | 1248 | } |
d18e0850 | 1249 | chan_mark_dead(c); |
97fb6912 | 1250 | } |
d18e0850 | 1251 | packet_send(); |
97fb6912 | 1252 | } |
1253 | } | |
1254 | ||
396c147e | 1255 | static int |
7368a6c8 | 1256 | channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset) |
1257 | { | |
1258 | char buf[16*1024]; | |
1259 | int len; | |
1260 | ||
6fd8622b | 1261 | if (c->rfd != -1 && |
7368a6c8 | 1262 | FD_ISSET(c->rfd, readset)) { |
1263 | len = read(c->rfd, buf, sizeof(buf)); | |
0fbe8c74 | 1264 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1265 | return 1; | |
7368a6c8 | 1266 | if (len <= 0) { |
0b242b12 | 1267 | debug("channel %d: read<=0 rfd %d len %d", |
7368a6c8 | 1268 | c->self, c->rfd, len); |
28b9cb4d | 1269 | if (c->type != SSH_CHANNEL_OPEN) { |
1270 | debug("channel %d: not open", c->self); | |
719fc62f | 1271 | chan_mark_dead(c); |
0490e609 | 1272 | return -1; |
28b9cb4d | 1273 | } else if (compat13) { |
9c50edcf | 1274 | buffer_clear(&c->output); |
7368a6c8 | 1275 | c->type = SSH_CHANNEL_INPUT_DRAINING; |
8e7895b8 | 1276 | debug("channel %d: input draining.", c->self); |
7368a6c8 | 1277 | } else { |
1278 | chan_read_failed(c); | |
5260325f | 1279 | } |
7368a6c8 | 1280 | return -1; |
1281 | } | |
6aacefa7 | 1282 | if (c->input_filter != NULL) { |
2e73a022 | 1283 | if (c->input_filter(c, buf, len) == -1) { |
070adba2 | 1284 | debug("channel %d: filter stops", c->self); |
2e73a022 | 1285 | chan_read_failed(c); |
1286 | } | |
1287 | } else { | |
1288 | buffer_append(&c->input, buf, len); | |
1289 | } | |
7368a6c8 | 1290 | } |
1291 | return 1; | |
1292 | } | |
396c147e | 1293 | static int |
7368a6c8 | 1294 | channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset) |
1295 | { | |
95ce5599 | 1296 | struct termios tio; |
780a9951 | 1297 | u_char *data; |
1298 | u_int dlen; | |
7368a6c8 | 1299 | int len; |
1300 | ||
1301 | /* Send buffered output data to the socket. */ | |
6fd8622b | 1302 | if (c->wfd != -1 && |
7368a6c8 | 1303 | FD_ISSET(c->wfd, writeset) && |
1304 | buffer_len(&c->output) > 0) { | |
780a9951 | 1305 | data = buffer_ptr(&c->output); |
1306 | dlen = buffer_len(&c->output); | |
1307 | len = write(c->wfd, data, dlen); | |
0fbe8c74 | 1308 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1309 | return 1; | |
7368a6c8 | 1310 | if (len <= 0) { |
28b9cb4d | 1311 | if (c->type != SSH_CHANNEL_OPEN) { |
1312 | debug("channel %d: not open", c->self); | |
719fc62f | 1313 | chan_mark_dead(c); |
28b9cb4d | 1314 | return -1; |
1315 | } else if (compat13) { | |
9c50edcf | 1316 | buffer_clear(&c->output); |
8e7895b8 | 1317 | debug("channel %d: input draining.", c->self); |
7368a6c8 | 1318 | c->type = SSH_CHANNEL_INPUT_DRAINING; |
1319 | } else { | |
1320 | chan_write_failed(c); | |
5260325f | 1321 | } |
7368a6c8 | 1322 | return -1; |
1323 | } | |
780a9951 | 1324 | if (compat20 && c->isatty && dlen >= 1 && data[0] != '\r') { |
0ae4fe1d | 1325 | if (tcgetattr(c->wfd, &tio) == 0 && |
1326 | !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) { | |
1327 | /* | |
1328 | * Simulate echo to reduce the impact of | |
355724fc | 1329 | * traffic analysis. We need to match the |
95ce5599 | 1330 | * size of a SSH2_MSG_CHANNEL_DATA message |
1331 | * (4 byte channel id + data) | |
0ae4fe1d | 1332 | */ |
95ce5599 | 1333 | packet_send_ignore(4 + len); |
0ae4fe1d | 1334 | packet_send(); |
0ae4fe1d | 1335 | } |
1336 | } | |
7368a6c8 | 1337 | buffer_consume(&c->output, len); |
7e7327a1 | 1338 | if (compat20 && len > 0) { |
1339 | c->local_consumed += len; | |
1340 | } | |
1341 | } | |
1342 | return 1; | |
1343 | } | |
396c147e | 1344 | static int |
7e7327a1 | 1345 | channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset) |
1346 | { | |
1347 | char buf[16*1024]; | |
1348 | int len; | |
1349 | ||
8ce64345 | 1350 | /** XXX handle drain efd, too */ |
7e7327a1 | 1351 | if (c->efd != -1) { |
1352 | if (c->extended_usage == CHAN_EXTENDED_WRITE && | |
1353 | FD_ISSET(c->efd, writeset) && | |
1354 | buffer_len(&c->extended) > 0) { | |
1355 | len = write(c->efd, buffer_ptr(&c->extended), | |
1356 | buffer_len(&c->extended)); | |
de273eef | 1357 | debug2("channel %d: written %d to efd %d", |
7e7327a1 | 1358 | c->self, len, c->efd); |
ee55dacf | 1359 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1360 | return 1; | |
1361 | if (len <= 0) { | |
1362 | debug2("channel %d: closing write-efd %d", | |
1363 | c->self, c->efd); | |
489aa2e9 | 1364 | channel_close_fd(&c->efd); |
ee55dacf | 1365 | } else { |
7e7327a1 | 1366 | buffer_consume(&c->extended, len); |
1367 | c->local_consumed += len; | |
1368 | } | |
1369 | } else if (c->extended_usage == CHAN_EXTENDED_READ && | |
1370 | FD_ISSET(c->efd, readset)) { | |
1371 | len = read(c->efd, buf, sizeof(buf)); | |
de273eef | 1372 | debug2("channel %d: read %d from efd %d", |
184eed6a | 1373 | c->self, len, c->efd); |
ee55dacf | 1374 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1375 | return 1; | |
1376 | if (len <= 0) { | |
1377 | debug2("channel %d: closing read-efd %d", | |
8ce64345 | 1378 | c->self, c->efd); |
489aa2e9 | 1379 | channel_close_fd(&c->efd); |
ee55dacf | 1380 | } else { |
7e7327a1 | 1381 | buffer_append(&c->extended, buf, len); |
ee55dacf | 1382 | } |
7e7327a1 | 1383 | } |
1384 | } | |
1385 | return 1; | |
1386 | } | |
396c147e | 1387 | static int |
ee55dacf | 1388 | channel_check_window(Channel *c) |
7e7327a1 | 1389 | { |
28b9cb4d | 1390 | if (c->type == SSH_CHANNEL_OPEN && |
1391 | !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) && | |
7e7327a1 | 1392 | c->local_window < c->local_window_max/2 && |
1393 | c->local_consumed > 0) { | |
1394 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); | |
1395 | packet_put_int(c->remote_id); | |
1396 | packet_put_int(c->local_consumed); | |
1397 | packet_send(); | |
de273eef | 1398 | debug2("channel %d: window %d sent adjust %d", |
7e7327a1 | 1399 | c->self, c->local_window, |
1400 | c->local_consumed); | |
1401 | c->local_window += c->local_consumed; | |
1402 | c->local_consumed = 0; | |
7368a6c8 | 1403 | } |
1404 | return 1; | |
1405 | } | |
5260325f | 1406 | |
396c147e | 1407 | static void |
0c0738d5 | 1408 | channel_post_open(Channel *c, fd_set * readset, fd_set * writeset) |
7368a6c8 | 1409 | { |
639cb8ab | 1410 | if (c->delayed) |
1411 | return; | |
7368a6c8 | 1412 | channel_handle_rfd(c, readset, writeset); |
1413 | channel_handle_wfd(c, readset, writeset); | |
0c0738d5 | 1414 | if (!compat20) |
639cb8ab | 1415 | return; |
7e7327a1 | 1416 | channel_handle_efd(c, readset, writeset); |
ee55dacf | 1417 | channel_check_window(c); |
7e7327a1 | 1418 | } |
1419 | ||
396c147e | 1420 | static void |
7368a6c8 | 1421 | channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset) |
1422 | { | |
1423 | int len; | |
1424 | /* Send buffered output data to the socket. */ | |
1425 | if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) { | |
1426 | len = write(c->sock, buffer_ptr(&c->output), | |
1427 | buffer_len(&c->output)); | |
1428 | if (len <= 0) | |
9c50edcf | 1429 | buffer_clear(&c->output); |
7368a6c8 | 1430 | else |
1431 | buffer_consume(&c->output, len); | |
1432 | } | |
1433 | } | |
5260325f | 1434 | |
396c147e | 1435 | static void |
7e7327a1 | 1436 | channel_handler_init_20(void) |
1437 | { | |
0c0738d5 | 1438 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open; |
0b242b12 | 1439 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; |
7e7327a1 | 1440 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; |
fa08c86b | 1441 | channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener; |
0b242b12 | 1442 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; |
fa08c86b | 1443 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; |
97fb6912 | 1444 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1445 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7e7327a1 | 1446 | |
0c0738d5 | 1447 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open; |
7e7327a1 | 1448 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; |
fa08c86b | 1449 | channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener; |
0b242b12 | 1450 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; |
fa08c86b | 1451 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; |
97fb6912 | 1452 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
0c0738d5 | 1453 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open; |
7e7327a1 | 1454 | } |
1455 | ||
396c147e | 1456 | static void |
7368a6c8 | 1457 | channel_handler_init_13(void) |
1458 | { | |
1459 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13; | |
1460 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13; | |
1461 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; | |
1462 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; | |
1463 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; | |
1464 | channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining; | |
1465 | channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining; | |
97fb6912 | 1466 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1467 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7368a6c8 | 1468 | |
0c0738d5 | 1469 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open; |
7368a6c8 | 1470 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; |
1471 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
1472 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; | |
1473 | channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13; | |
97fb6912 | 1474 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
0c0738d5 | 1475 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open; |
7368a6c8 | 1476 | } |
5260325f | 1477 | |
396c147e | 1478 | static void |
7368a6c8 | 1479 | channel_handler_init_15(void) |
1480 | { | |
0c0738d5 | 1481 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open; |
0b242b12 | 1482 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; |
7368a6c8 | 1483 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; |
1484 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; | |
1485 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; | |
97fb6912 | 1486 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1487 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7368a6c8 | 1488 | |
1489 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; | |
1490 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
1491 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; | |
0c0738d5 | 1492 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open; |
97fb6912 | 1493 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
0c0738d5 | 1494 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open; |
7368a6c8 | 1495 | } |
1496 | ||
396c147e | 1497 | static void |
7368a6c8 | 1498 | channel_handler_init(void) |
1499 | { | |
1500 | int i; | |
184eed6a | 1501 | for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) { |
7368a6c8 | 1502 | channel_pre[i] = NULL; |
1503 | channel_post[i] = NULL; | |
1504 | } | |
7e7327a1 | 1505 | if (compat20) |
1506 | channel_handler_init_20(); | |
1507 | else if (compat13) | |
7368a6c8 | 1508 | channel_handler_init_13(); |
1509 | else | |
1510 | channel_handler_init_15(); | |
1511 | } | |
1512 | ||
418e724c | 1513 | /* gc dead channels */ |
1514 | static void | |
1515 | channel_garbage_collect(Channel *c) | |
1516 | { | |
1517 | if (c == NULL) | |
1518 | return; | |
1519 | if (c->detach_user != NULL) { | |
1520 | if (!chan_is_dead(c, 0)) | |
1521 | return; | |
1522 | debug("channel %d: gc: notify user", c->self); | |
1523 | c->detach_user(c->self, NULL); | |
1524 | /* if we still have a callback */ | |
1525 | if (c->detach_user != NULL) | |
1526 | return; | |
1527 | debug("channel %d: gc: user detached", c->self); | |
1528 | } | |
1529 | if (!chan_is_dead(c, 1)) | |
1530 | return; | |
1531 | debug("channel %d: garbage collecting", c->self); | |
1532 | channel_free(c); | |
1533 | } | |
1534 | ||
396c147e | 1535 | static void |
7368a6c8 | 1536 | channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset) |
1537 | { | |
1538 | static int did_init = 0; | |
1539 | int i; | |
1540 | Channel *c; | |
1541 | ||
1542 | if (!did_init) { | |
1543 | channel_handler_init(); | |
1544 | did_init = 1; | |
1545 | } | |
1546 | for (i = 0; i < channels_alloc; i++) { | |
719fc62f | 1547 | c = channels[i]; |
1548 | if (c == NULL) | |
5260325f | 1549 | continue; |
6fd8622b | 1550 | if (ftab[c->type] != NULL) |
1551 | (*ftab[c->type])(c, readset, writeset); | |
418e724c | 1552 | channel_garbage_collect(c); |
8efc0c15 | 1553 | } |
8efc0c15 | 1554 | } |
1555 | ||
8e7895b8 | 1556 | /* |
1557 | * Allocate/update select bitmasks and add any bits relevant to channels in | |
1558 | * select bitmasks. | |
1559 | */ | |
6ae2364d | 1560 | void |
c422989b | 1561 | channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp, |
489aa2e9 | 1562 | int *nallocp, int rekeying) |
7368a6c8 | 1563 | { |
39929cdb | 1564 | int n; |
1565 | u_int sz; | |
1566 | ||
1567 | n = MAX(*maxfdp, channel_max_fd); | |
1568 | ||
1569 | sz = howmany(n+1, NFDBITS) * sizeof(fd_mask); | |
489aa2e9 | 1570 | /* perhaps check sz < nalloc/2 and shrink? */ |
1571 | if (*readsetp == NULL || sz > *nallocp) { | |
1572 | *readsetp = xrealloc(*readsetp, sz); | |
1573 | *writesetp = xrealloc(*writesetp, sz); | |
1574 | *nallocp = sz; | |
39929cdb | 1575 | } |
489aa2e9 | 1576 | *maxfdp = n; |
39929cdb | 1577 | memset(*readsetp, 0, sz); |
1578 | memset(*writesetp, 0, sz); | |
1579 | ||
c422989b | 1580 | if (!rekeying) |
1581 | channel_handler(channel_pre, *readsetp, *writesetp); | |
7368a6c8 | 1582 | } |
1583 | ||
8e7895b8 | 1584 | /* |
1585 | * After select, perform any appropriate operations for channels which have | |
1586 | * events pending. | |
1587 | */ | |
6ae2364d | 1588 | void |
7368a6c8 | 1589 | channel_after_select(fd_set * readset, fd_set * writeset) |
1590 | { | |
1591 | channel_handler(channel_post, readset, writeset); | |
1592 | } | |
1593 | ||
8e7895b8 | 1594 | |
39929cdb | 1595 | /* If there is data to send to the connection, enqueue some of it now. */ |
8efc0c15 | 1596 | |
6ae2364d | 1597 | void |
d5bb9418 | 1598 | channel_output_poll(void) |
8efc0c15 | 1599 | { |
5260325f | 1600 | int len, i; |
7368a6c8 | 1601 | Channel *c; |
5260325f | 1602 | |
1603 | for (i = 0; i < channels_alloc; i++) { | |
719fc62f | 1604 | c = channels[i]; |
1605 | if (c == NULL) | |
1606 | continue; | |
48e671d5 | 1607 | |
8e7895b8 | 1608 | /* |
1609 | * We are only interested in channels that can have buffered | |
1610 | * incoming data. | |
1611 | */ | |
48e671d5 | 1612 | if (compat13) { |
7368a6c8 | 1613 | if (c->type != SSH_CHANNEL_OPEN && |
1614 | c->type != SSH_CHANNEL_INPUT_DRAINING) | |
48e671d5 | 1615 | continue; |
1616 | } else { | |
7368a6c8 | 1617 | if (c->type != SSH_CHANNEL_OPEN) |
48e671d5 | 1618 | continue; |
48e671d5 | 1619 | } |
e78a59f5 | 1620 | if (compat20 && |
1621 | (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) { | |
ee55dacf | 1622 | /* XXX is this true? */ |
418e724c | 1623 | debug3("channel %d: will not send data after close", c->self); |
7e7327a1 | 1624 | continue; |
1625 | } | |
5260325f | 1626 | |
1627 | /* Get the amount of buffered data for this channel. */ | |
ee55dacf | 1628 | if ((c->istate == CHAN_INPUT_OPEN || |
1629 | c->istate == CHAN_INPUT_WAIT_DRAIN) && | |
1630 | (len = buffer_len(&c->input)) > 0) { | |
8e7895b8 | 1631 | /* |
1632 | * Send some data for the other side over the secure | |
1633 | * connection. | |
1634 | */ | |
7e7327a1 | 1635 | if (compat20) { |
1636 | if (len > c->remote_window) | |
1637 | len = c->remote_window; | |
1638 | if (len > c->remote_maxpacket) | |
1639 | len = c->remote_maxpacket; | |
5260325f | 1640 | } else { |
7e7327a1 | 1641 | if (packet_is_interactive()) { |
1642 | if (len > 1024) | |
1643 | len = 512; | |
1644 | } else { | |
1645 | /* Keep the packets at reasonable size. */ | |
1646 | if (len > packet_get_maxsize()/2) | |
1647 | len = packet_get_maxsize()/2; | |
1648 | } | |
5260325f | 1649 | } |
7368a6c8 | 1650 | if (len > 0) { |
7e7327a1 | 1651 | packet_start(compat20 ? |
1652 | SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA); | |
7368a6c8 | 1653 | packet_put_int(c->remote_id); |
1654 | packet_put_string(buffer_ptr(&c->input), len); | |
1655 | packet_send(); | |
1656 | buffer_consume(&c->input, len); | |
1657 | c->remote_window -= len; | |
7368a6c8 | 1658 | } |
1659 | } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) { | |
5260325f | 1660 | if (compat13) |
1661 | fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3"); | |
aa3378df | 1662 | /* |
1663 | * input-buffer is empty and read-socket shutdown: | |
1664 | * tell peer, that we will not send more data: send IEOF | |
1665 | */ | |
7368a6c8 | 1666 | chan_ibuf_empty(c); |
5260325f | 1667 | } |
7e7327a1 | 1668 | /* Send extended data, i.e. stderr */ |
1669 | if (compat20 && | |
1670 | c->remote_window > 0 && | |
1671 | (len = buffer_len(&c->extended)) > 0 && | |
1672 | c->extended_usage == CHAN_EXTENDED_READ) { | |
ee55dacf | 1673 | debug2("channel %d: rwin %d elen %d euse %d", |
1674 | c->self, c->remote_window, buffer_len(&c->extended), | |
1675 | c->extended_usage); | |
7e7327a1 | 1676 | if (len > c->remote_window) |
1677 | len = c->remote_window; | |
1678 | if (len > c->remote_maxpacket) | |
1679 | len = c->remote_maxpacket; | |
1680 | packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA); | |
1681 | packet_put_int(c->remote_id); | |
1682 | packet_put_int(SSH2_EXTENDED_DATA_STDERR); | |
1683 | packet_put_string(buffer_ptr(&c->extended), len); | |
1684 | packet_send(); | |
1685 | buffer_consume(&c->extended, len); | |
1686 | c->remote_window -= len; | |
ee55dacf | 1687 | debug2("channel %d: sent ext data %d", c->self, len); |
7e7327a1 | 1688 | } |
8efc0c15 | 1689 | } |
8efc0c15 | 1690 | } |
1691 | ||
8e7895b8 | 1692 | |
1693 | /* -- protocol input */ | |
8efc0c15 | 1694 | |
6ae2364d | 1695 | void |
7819b5c3 | 1696 | channel_input_data(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 1697 | { |
48e671d5 | 1698 | int id; |
5260325f | 1699 | char *data; |
1e3b8b07 | 1700 | u_int data_len; |
7368a6c8 | 1701 | Channel *c; |
5260325f | 1702 | |
1703 | /* Get the channel number and verify it. */ | |
48e671d5 | 1704 | id = packet_get_int(); |
7368a6c8 | 1705 | c = channel_lookup(id); |
1706 | if (c == NULL) | |
48e671d5 | 1707 | packet_disconnect("Received data for nonexistent channel %d.", id); |
5260325f | 1708 | |
1709 | /* Ignore any data for non-open channels (might happen on close) */ | |
7368a6c8 | 1710 | if (c->type != SSH_CHANNEL_OPEN && |
1711 | c->type != SSH_CHANNEL_X11_OPEN) | |
48e671d5 | 1712 | return; |
1713 | ||
1714 | /* same for protocol 1.5 if output end is no longer open */ | |
7368a6c8 | 1715 | if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) |
5260325f | 1716 | return; |
1717 | ||
1718 | /* Get the data. */ | |
1719 | data = packet_get_string(&data_len); | |
7368a6c8 | 1720 | |
6aacefa7 | 1721 | if (compat20) { |
7e7327a1 | 1722 | if (data_len > c->local_maxpacket) { |
1723 | log("channel %d: rcvd big packet %d, maxpack %d", | |
1724 | c->self, data_len, c->local_maxpacket); | |
1725 | } | |
1726 | if (data_len > c->local_window) { | |
1727 | log("channel %d: rcvd too much data %d, win %d", | |
1728 | c->self, data_len, c->local_window); | |
1729 | xfree(data); | |
1730 | return; | |
1731 | } | |
1732 | c->local_window -= data_len; | |
7e7327a1 | 1733 | } |
95500969 | 1734 | packet_check_eom(); |
7368a6c8 | 1735 | buffer_append(&c->output, data, data_len); |
5260325f | 1736 | xfree(data); |
8efc0c15 | 1737 | } |
8e7895b8 | 1738 | |
6ae2364d | 1739 | void |
7819b5c3 | 1740 | channel_input_extended_data(int type, u_int32_t seq, void *ctxt) |
7e7327a1 | 1741 | { |
1742 | int id; | |
1743 | int tcode; | |
1744 | char *data; | |
1e3b8b07 | 1745 | u_int data_len; |
7e7327a1 | 1746 | Channel *c; |
1747 | ||
1748 | /* Get the channel number and verify it. */ | |
1749 | id = packet_get_int(); | |
1750 | c = channel_lookup(id); | |
1751 | ||
1752 | if (c == NULL) | |
1753 | packet_disconnect("Received extended_data for bad channel %d.", id); | |
1754 | if (c->type != SSH_CHANNEL_OPEN) { | |
1755 | log("channel %d: ext data for non open", id); | |
1756 | return; | |
1757 | } | |
1758 | tcode = packet_get_int(); | |
1759 | if (c->efd == -1 || | |
1760 | c->extended_usage != CHAN_EXTENDED_WRITE || | |
1761 | tcode != SSH2_EXTENDED_DATA_STDERR) { | |
1762 | log("channel %d: bad ext data", c->self); | |
1763 | return; | |
1764 | } | |
1765 | data = packet_get_string(&data_len); | |
95500969 | 1766 | packet_check_eom(); |
7e7327a1 | 1767 | if (data_len > c->local_window) { |
1768 | log("channel %d: rcvd too much extended_data %d, win %d", | |
1769 | c->self, data_len, c->local_window); | |
1770 | xfree(data); | |
1771 | return; | |
1772 | } | |
de273eef | 1773 | debug2("channel %d: rcvd ext data %d", c->self, data_len); |
7e7327a1 | 1774 | c->local_window -= data_len; |
1775 | buffer_append(&c->extended, data, data_len); | |
1776 | xfree(data); | |
1777 | } | |
1778 | ||
6ae2364d | 1779 | void |
7819b5c3 | 1780 | channel_input_ieof(int type, u_int32_t seq, void *ctxt) |
7368a6c8 | 1781 | { |
1782 | int id; | |
1783 | Channel *c; | |
1784 | ||
7368a6c8 | 1785 | id = packet_get_int(); |
95500969 | 1786 | packet_check_eom(); |
7368a6c8 | 1787 | c = channel_lookup(id); |
1788 | if (c == NULL) | |
1789 | packet_disconnect("Received ieof for nonexistent channel %d.", id); | |
1790 | chan_rcvd_ieof(c); | |
a5f82435 | 1791 | |
1792 | /* XXX force input close */ | |
8341f420 | 1793 | if (c->force_drain && c->istate == CHAN_INPUT_OPEN) { |
a5f82435 | 1794 | debug("channel %d: FORCE input drain", c->self); |
1795 | c->istate = CHAN_INPUT_WAIT_DRAIN; | |
1796 | } | |
1797 | ||
7368a6c8 | 1798 | } |
8efc0c15 | 1799 | |
6ae2364d | 1800 | void |
7819b5c3 | 1801 | channel_input_close(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 1802 | { |
7368a6c8 | 1803 | int id; |
1804 | Channel *c; | |
5260325f | 1805 | |
7368a6c8 | 1806 | id = packet_get_int(); |
95500969 | 1807 | packet_check_eom(); |
7368a6c8 | 1808 | c = channel_lookup(id); |
1809 | if (c == NULL) | |
1810 | packet_disconnect("Received close for nonexistent channel %d.", id); | |
aa3378df | 1811 | |
1812 | /* | |
1813 | * Send a confirmation that we have closed the channel and no more | |
1814 | * data is coming for it. | |
1815 | */ | |
5260325f | 1816 | packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION); |
7368a6c8 | 1817 | packet_put_int(c->remote_id); |
5260325f | 1818 | packet_send(); |
1819 | ||
aa3378df | 1820 | /* |
1821 | * If the channel is in closed state, we have sent a close request, | |
1822 | * and the other side will eventually respond with a confirmation. | |
1823 | * Thus, we cannot free the channel here, because then there would be | |
1824 | * no-one to receive the confirmation. The channel gets freed when | |
1825 | * the confirmation arrives. | |
1826 | */ | |
7368a6c8 | 1827 | if (c->type != SSH_CHANNEL_CLOSED) { |
aa3378df | 1828 | /* |
1829 | * Not a closed channel - mark it as draining, which will | |
1830 | * cause it to be freed later. | |
1831 | */ | |
9c50edcf | 1832 | buffer_clear(&c->input); |
7368a6c8 | 1833 | c->type = SSH_CHANNEL_OUTPUT_DRAINING; |
5260325f | 1834 | } |
8efc0c15 | 1835 | } |
1836 | ||
7368a6c8 | 1837 | /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */ |
6ae2364d | 1838 | void |
7819b5c3 | 1839 | channel_input_oclose(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 1840 | { |
7368a6c8 | 1841 | int id = packet_get_int(); |
1842 | Channel *c = channel_lookup(id); | |
a8a21a53 | 1843 | |
95500969 | 1844 | packet_check_eom(); |
7368a6c8 | 1845 | if (c == NULL) |
1846 | packet_disconnect("Received oclose for nonexistent channel %d.", id); | |
1847 | chan_rcvd_oclose(c); | |
8efc0c15 | 1848 | } |
1849 | ||
6ae2364d | 1850 | void |
7819b5c3 | 1851 | channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt) |
7368a6c8 | 1852 | { |
1853 | int id = packet_get_int(); | |
1854 | Channel *c = channel_lookup(id); | |
1855 | ||
95500969 | 1856 | packet_check_eom(); |
7368a6c8 | 1857 | if (c == NULL) |
1858 | packet_disconnect("Received close confirmation for " | |
1859 | "out-of-range channel %d.", id); | |
1860 | if (c->type != SSH_CHANNEL_CLOSED) | |
1861 | packet_disconnect("Received close confirmation for " | |
1862 | "non-closed channel %d (type %d).", id, c->type); | |
719fc62f | 1863 | channel_free(c); |
7368a6c8 | 1864 | } |
8efc0c15 | 1865 | |
6ae2364d | 1866 | void |
7819b5c3 | 1867 | channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 1868 | { |
7368a6c8 | 1869 | int id, remote_id; |
1870 | Channel *c; | |
5260325f | 1871 | |
7368a6c8 | 1872 | id = packet_get_int(); |
1873 | c = channel_lookup(id); | |
5260325f | 1874 | |
7368a6c8 | 1875 | if (c==NULL || c->type != SSH_CHANNEL_OPENING) |
1876 | packet_disconnect("Received open confirmation for " | |
1877 | "non-opening channel %d.", id); | |
1878 | remote_id = packet_get_int(); | |
aa3378df | 1879 | /* Record the remote channel number and mark that the channel is now open. */ |
7368a6c8 | 1880 | c->remote_id = remote_id; |
1881 | c->type = SSH_CHANNEL_OPEN; | |
7e7327a1 | 1882 | |
1883 | if (compat20) { | |
1884 | c->remote_window = packet_get_int(); | |
1885 | c->remote_maxpacket = packet_get_int(); | |
1886 | if (c->cb_fn != NULL && c->cb_event == type) { | |
de273eef | 1887 | debug2("callback start"); |
7e7327a1 | 1888 | c->cb_fn(c->self, c->cb_arg); |
de273eef | 1889 | debug2("callback done"); |
7e7327a1 | 1890 | } |
1891 | debug("channel %d: open confirm rwindow %d rmax %d", c->self, | |
1892 | c->remote_window, c->remote_maxpacket); | |
1893 | } | |
95500969 | 1894 | packet_check_eom(); |
8efc0c15 | 1895 | } |
1896 | ||
396c147e | 1897 | static char * |
d18e0850 | 1898 | reason2txt(int reason) |
1899 | { | |
6aacefa7 | 1900 | switch (reason) { |
d18e0850 | 1901 | case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED: |
1902 | return "administratively prohibited"; | |
1903 | case SSH2_OPEN_CONNECT_FAILED: | |
1904 | return "connect failed"; | |
1905 | case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE: | |
1906 | return "unknown channel type"; | |
1907 | case SSH2_OPEN_RESOURCE_SHORTAGE: | |
1908 | return "resource shortage"; | |
1909 | } | |
7e8c18e9 | 1910 | return "unknown reason"; |
d18e0850 | 1911 | } |
1912 | ||
6ae2364d | 1913 | void |
7819b5c3 | 1914 | channel_input_open_failure(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 1915 | { |
02a024dd | 1916 | int id, reason; |
1917 | char *msg = NULL, *lang = NULL; | |
7368a6c8 | 1918 | Channel *c; |
5260325f | 1919 | |
7368a6c8 | 1920 | id = packet_get_int(); |
1921 | c = channel_lookup(id); | |
1922 | ||
1923 | if (c==NULL || c->type != SSH_CHANNEL_OPENING) | |
1924 | packet_disconnect("Received open failure for " | |
1925 | "non-opening channel %d.", id); | |
7e7327a1 | 1926 | if (compat20) { |
02a024dd | 1927 | reason = packet_get_int(); |
fbe90f7b | 1928 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { |
02a024dd | 1929 | msg = packet_get_string(NULL); |
1930 | lang = packet_get_string(NULL); | |
1931 | } | |
d18e0850 | 1932 | log("channel %d: open failed: %s%s%s", id, |
1933 | reason2txt(reason), msg ? ": ": "", msg ? msg : ""); | |
02a024dd | 1934 | if (msg != NULL) |
1935 | xfree(msg); | |
1936 | if (lang != NULL) | |
1937 | xfree(lang); | |
7e7327a1 | 1938 | } |
95500969 | 1939 | packet_check_eom(); |
5260325f | 1940 | /* Free the channel. This will also close the socket. */ |
719fc62f | 1941 | channel_free(c); |
8efc0c15 | 1942 | } |
1943 | ||
7e7327a1 | 1944 | void |
7819b5c3 | 1945 | channel_input_channel_request(int type, u_int32_t seq, void *ctxt) |
7e7327a1 | 1946 | { |
1947 | int id; | |
1948 | Channel *c; | |
1949 | ||
1950 | id = packet_get_int(); | |
1951 | c = channel_lookup(id); | |
1952 | ||
1953 | if (c == NULL || | |
1954 | (c->type != SSH_CHANNEL_OPEN && c->type != SSH_CHANNEL_LARVAL)) | |
1955 | packet_disconnect("Received request for " | |
1956 | "non-open channel %d.", id); | |
1957 | if (c->cb_fn != NULL && c->cb_event == type) { | |
de273eef | 1958 | debug2("callback start"); |
7e7327a1 | 1959 | c->cb_fn(c->self, c->cb_arg); |
de273eef | 1960 | debug2("callback done"); |
8e7895b8 | 1961 | } else { |
1962 | char *service = packet_get_string(NULL); | |
1963 | debug("channel %d: rcvd request for %s", c->self, service); | |
1964 | debug("cb_fn %p cb_event %d", c->cb_fn , c->cb_event); | |
1965 | xfree(service); | |
719fc62f | 1966 | } |
3ffc6336 | 1967 | } |
1968 | ||
8e7895b8 | 1969 | void |
7819b5c3 | 1970 | channel_input_window_adjust(int type, u_int32_t seq, void *ctxt) |
8e7895b8 | 1971 | { |
1972 | Channel *c; | |
1973 | int id, adjust; | |
3ffc6336 | 1974 | |
8e7895b8 | 1975 | if (!compat20) |
1976 | return; | |
8efc0c15 | 1977 | |
8e7895b8 | 1978 | /* Get the channel number and verify it. */ |
1979 | id = packet_get_int(); | |
1980 | c = channel_lookup(id); | |
1981 | ||
1982 | if (c == NULL || c->type != SSH_CHANNEL_OPEN) { | |
1983 | log("Received window adjust for " | |
1984 | "non-open channel %d.", id); | |
1985 | return; | |
1986 | } | |
1987 | adjust = packet_get_int(); | |
95500969 | 1988 | packet_check_eom(); |
8e7895b8 | 1989 | debug2("channel %d: rcvd adjust %d", id, adjust); |
1990 | c->remote_window += adjust; | |
1991 | } | |
1992 | ||
1993 | void | |
7819b5c3 | 1994 | channel_input_port_open(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 1995 | { |
8e7895b8 | 1996 | Channel *c = NULL; |
1997 | u_short host_port; | |
1998 | char *host, *originator_string; | |
1999 | int remote_id, sock = -1; | |
5260325f | 2000 | |
8e7895b8 | 2001 | remote_id = packet_get_int(); |
2002 | host = packet_get_string(NULL); | |
2003 | host_port = packet_get_int(); | |
2004 | ||
2005 | if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) { | |
2006 | originator_string = packet_get_string(NULL); | |
2007 | } else { | |
2008 | originator_string = xstrdup("unknown (remote did not supply name)"); | |
2009 | } | |
95500969 | 2010 | packet_check_eom(); |
8e7895b8 | 2011 | sock = channel_connect_to(host, host_port); |
2012 | if (sock != -1) { | |
2013 | c = channel_new("connected socket", | |
2014 | SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0, | |
2015 | originator_string, 1); | |
2016 | if (c == NULL) { | |
2017 | error("channel_input_port_open: channel_new failed"); | |
2018 | close(sock); | |
2019 | } else { | |
2020 | c->remote_id = remote_id; | |
5260325f | 2021 | } |
2022 | } | |
8e7895b8 | 2023 | if (c == NULL) { |
2024 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
2025 | packet_put_int(remote_id); | |
2026 | packet_send(); | |
2027 | } | |
2028 | xfree(host); | |
8efc0c15 | 2029 | } |
2030 | ||
8e7895b8 | 2031 | |
2032 | /* -- tcp forwarding */ | |
2033 | ||
5e4a7219 | 2034 | void |
2035 | channel_set_af(int af) | |
2036 | { | |
2037 | IPv4or6 = af; | |
2038 | } | |
2039 | ||
aa3378df | 2040 | /* |
2041 | * Initiate forwarding of connections to local port "port" through the secure | |
2042 | * channel to host:port from remote side. | |
2043 | */ | |
02a024dd | 2044 | int |
fa08c86b | 2045 | channel_request_local_forwarding(u_short listen_port, const char *host_to_connect, |
2046 | u_short port_to_connect, int gateway_ports) | |
2047 | { | |
02a024dd | 2048 | return channel_request_forwarding( |
fa08c86b | 2049 | NULL, listen_port, |
2050 | host_to_connect, port_to_connect, | |
2051 | gateway_ports, /*remote_fwd*/ 0); | |
2052 | } | |
8efc0c15 | 2053 | |
fa08c86b | 2054 | /* |
2055 | * If 'remote_fwd' is true we have a '-R style' listener for protocol 2 | |
2056 | * (SSH_CHANNEL_RPORT_LISTENER). | |
2057 | */ | |
02a024dd | 2058 | int |
fa08c86b | 2059 | channel_request_forwarding( |
2060 | const char *listen_address, u_short listen_port, | |
2061 | const char *host_to_connect, u_short port_to_connect, | |
2062 | int gateway_ports, int remote_fwd) | |
8efc0c15 | 2063 | { |
719fc62f | 2064 | Channel *c; |
8e7895b8 | 2065 | int success, sock, on = 1, type; |
48e671d5 | 2066 | struct addrinfo hints, *ai, *aitop; |
2067 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; | |
fa08c86b | 2068 | const char *host; |
aa3378df | 2069 | struct linger linger; |
5260325f | 2070 | |
02a024dd | 2071 | success = 0; |
2072 | ||
fa08c86b | 2073 | if (remote_fwd) { |
2074 | host = listen_address; | |
8e7895b8 | 2075 | type = SSH_CHANNEL_RPORT_LISTENER; |
fa08c86b | 2076 | } else { |
2077 | host = host_to_connect; | |
8e7895b8 | 2078 | type = SSH_CHANNEL_PORT_LISTENER; |
fa08c86b | 2079 | } |
2080 | ||
719fc62f | 2081 | if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) { |
02a024dd | 2082 | error("Forward host name too long."); |
2083 | return success; | |
2084 | } | |
5260325f | 2085 | |
fa08c86b | 2086 | /* XXX listen_address is currently ignored */ |
aa3378df | 2087 | /* |
48e671d5 | 2088 | * getaddrinfo returns a loopback address if the hostname is |
2089 | * set to NULL and hints.ai_flags is not AI_PASSIVE | |
aa3378df | 2090 | */ |
48e671d5 | 2091 | memset(&hints, 0, sizeof(hints)); |
2092 | hints.ai_family = IPv4or6; | |
2093 | hints.ai_flags = gateway_ports ? AI_PASSIVE : 0; | |
2094 | hints.ai_socktype = SOCK_STREAM; | |
fa08c86b | 2095 | snprintf(strport, sizeof strport, "%d", listen_port); |
48e671d5 | 2096 | if (getaddrinfo(NULL, strport, &hints, &aitop) != 0) |
2097 | packet_disconnect("getaddrinfo: fatal error"); | |
2098 | ||
48e671d5 | 2099 | for (ai = aitop; ai; ai = ai->ai_next) { |
2100 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2101 | continue; | |
2102 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), | |
2103 | strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
fa08c86b | 2104 | error("channel_request_forwarding: getnameinfo failed"); |
48e671d5 | 2105 | continue; |
2106 | } | |
2107 | /* Create a port to listen for the host. */ | |
2108 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
2109 | if (sock < 0) { | |
2110 | /* this is no error since kernel may not support ipv6 */ | |
2111 | verbose("socket: %.100s", strerror(errno)); | |
2112 | continue; | |
2113 | } | |
2114 | /* | |
2115 | * Set socket options. We would like the socket to disappear | |
2116 | * as soon as it has been closed for whatever reason. | |
2117 | */ | |
2118 | setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on)); | |
2119 | linger.l_onoff = 1; | |
2120 | linger.l_linger = 5; | |
2121 | setsockopt(sock, SOL_SOCKET, SO_LINGER, (void *)&linger, sizeof(linger)); | |
2122 | debug("Local forwarding listening on %s port %s.", ntop, strport); | |
2123 | ||
2124 | /* Bind the socket to the address. */ | |
2125 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
2126 | /* address can be in use ipv6 address is already bound */ | |
16218745 | 2127 | if (!ai->ai_next) |
2128 | error("bind: %.100s", strerror(errno)); | |
2129 | else | |
2130 | verbose("bind: %.100s", strerror(errno)); | |
2b87da3b | 2131 | |
48e671d5 | 2132 | close(sock); |
2133 | continue; | |
2134 | } | |
2135 | /* Start listening for connections on the socket. */ | |
2136 | if (listen(sock, 5) < 0) { | |
2137 | error("listen: %.100s", strerror(errno)); | |
2138 | close(sock); | |
2139 | continue; | |
2140 | } | |
2141 | /* Allocate a channel number for the socket. */ | |
8e7895b8 | 2142 | c = channel_new("port listener", type, sock, sock, -1, |
0b242b12 | 2143 | CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, |
a22aff1f | 2144 | 0, xstrdup("port listener"), 1); |
719fc62f | 2145 | if (c == NULL) { |
2146 | error("channel_request_forwarding: channel_new failed"); | |
2147 | close(sock); | |
2148 | continue; | |
2149 | } | |
2150 | strlcpy(c->path, host, sizeof(c->path)); | |
2151 | c->host_port = port_to_connect; | |
2152 | c->listening_port = listen_port; | |
48e671d5 | 2153 | success = 1; |
2154 | } | |
2155 | if (success == 0) | |
02a024dd | 2156 | error("channel_request_forwarding: cannot listen to port: %d", |
2157 | listen_port); | |
48e671d5 | 2158 | freeaddrinfo(aitop); |
02a024dd | 2159 | return success; |
5260325f | 2160 | } |
8efc0c15 | 2161 | |
aa3378df | 2162 | /* |
2163 | * Initiate forwarding of connections to port "port" on remote host through | |
2164 | * the secure channel to host:port from local side. | |
2165 | */ | |
8efc0c15 | 2166 | |
6ae2364d | 2167 | void |
fa08c86b | 2168 | channel_request_remote_forwarding(u_short listen_port, |
2169 | const char *host_to_connect, u_short port_to_connect) | |
8efc0c15 | 2170 | { |
54a5250f | 2171 | int type, success = 0; |
fa08c86b | 2172 | |
5260325f | 2173 | /* Record locally that connection to this host/port is permitted. */ |
2174 | if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION) | |
2175 | fatal("channel_request_remote_forwarding: too many forwards"); | |
2176 | ||
5260325f | 2177 | /* Send the forward request to the remote side. */ |
7e7327a1 | 2178 | if (compat20) { |
2179 | const char *address_to_bind = "0.0.0.0"; | |
2180 | packet_start(SSH2_MSG_GLOBAL_REQUEST); | |
2181 | packet_put_cstring("tcpip-forward"); | |
2182 | packet_put_char(0); /* boolean: want reply */ | |
2183 | packet_put_cstring(address_to_bind); | |
2184 | packet_put_int(listen_port); | |
fa08c86b | 2185 | packet_send(); |
2186 | packet_write_wait(); | |
2187 | /* Assume that server accepts the request */ | |
2188 | success = 1; | |
7e7327a1 | 2189 | } else { |
2190 | packet_start(SSH_CMSG_PORT_FORWARD_REQUEST); | |
7e7327a1 | 2191 | packet_put_int(listen_port); |
d6f24e45 | 2192 | packet_put_cstring(host_to_connect); |
2193 | packet_put_int(port_to_connect); | |
7e7327a1 | 2194 | packet_send(); |
2195 | packet_write_wait(); | |
fa08c86b | 2196 | |
2197 | /* Wait for response from the remote side. */ | |
54a5250f | 2198 | type = packet_read(); |
fa08c86b | 2199 | switch (type) { |
2200 | case SSH_SMSG_SUCCESS: | |
2201 | success = 1; | |
2202 | break; | |
2203 | case SSH_SMSG_FAILURE: | |
2204 | log("Warning: Server denied remote port forwarding."); | |
2205 | break; | |
2206 | default: | |
2207 | /* Unknown packet */ | |
2208 | packet_disconnect("Protocol error for port forward request:" | |
2209 | "received packet type %d.", type); | |
2210 | } | |
2211 | } | |
2212 | if (success) { | |
2213 | permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect); | |
2214 | permitted_opens[num_permitted_opens].port_to_connect = port_to_connect; | |
2215 | permitted_opens[num_permitted_opens].listen_port = listen_port; | |
2216 | num_permitted_opens++; | |
7e7327a1 | 2217 | } |
8efc0c15 | 2218 | } |
2219 | ||
aa3378df | 2220 | /* |
2221 | * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates | |
2222 | * listening for the port, and sends back a success reply (or disconnect | |
2223 | * message if there was an error). This never returns if there was an error. | |
2224 | */ | |
8efc0c15 | 2225 | |
6ae2364d | 2226 | void |
1d1ffb87 | 2227 | channel_input_port_forward_request(int is_root, int gateway_ports) |
8efc0c15 | 2228 | { |
57112b5a | 2229 | u_short port, host_port; |
5260325f | 2230 | char *hostname; |
2231 | ||
2232 | /* Get arguments from the packet. */ | |
2233 | port = packet_get_int(); | |
2234 | hostname = packet_get_string(NULL); | |
2235 | host_port = packet_get_int(); | |
2236 | ||
3c62e7eb | 2237 | #ifndef HAVE_CYGWIN |
aa3378df | 2238 | /* |
2239 | * Check that an unprivileged user is not trying to forward a | |
2240 | * privileged port. | |
2241 | */ | |
5260325f | 2242 | if (port < IPPORT_RESERVED && !is_root) |
2243 | packet_disconnect("Requested forwarding of port %d but user is not root.", | |
2244 | port); | |
3c62e7eb | 2245 | #endif |
fa08c86b | 2246 | /* Initiate forwarding */ |
1d1ffb87 | 2247 | channel_request_local_forwarding(port, hostname, host_port, gateway_ports); |
5260325f | 2248 | |
2249 | /* Free the argument string. */ | |
2250 | xfree(hostname); | |
8efc0c15 | 2251 | } |
2252 | ||
01794848 | 2253 | /* |
2254 | * Permits opening to any host/port if permitted_opens[] is empty. This is | |
2255 | * usually called by the server, because the user could connect to any port | |
2256 | * anyway, and the server has no way to know but to trust the client anyway. | |
2257 | */ | |
2258 | void | |
d5bb9418 | 2259 | channel_permit_all_opens(void) |
01794848 | 2260 | { |
2261 | if (num_permitted_opens == 0) | |
2262 | all_opens_permitted = 1; | |
2263 | } | |
2264 | ||
cd332296 | 2265 | void |
01794848 | 2266 | channel_add_permitted_opens(char *host, int port) |
2267 | { | |
2268 | if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION) | |
2269 | fatal("channel_request_remote_forwarding: too many forwards"); | |
2270 | debug("allow port forwarding to host %s port %d", host, port); | |
2271 | ||
2272 | permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host); | |
2273 | permitted_opens[num_permitted_opens].port_to_connect = port; | |
2274 | num_permitted_opens++; | |
2275 | ||
2276 | all_opens_permitted = 0; | |
2277 | } | |
2278 | ||
cd332296 | 2279 | void |
01794848 | 2280 | channel_clear_permitted_opens(void) |
2281 | { | |
2282 | int i; | |
2283 | ||
2284 | for (i = 0; i < num_permitted_opens; i++) | |
2285 | xfree(permitted_opens[i].host_to_connect); | |
2286 | num_permitted_opens = 0; | |
2287 | ||
2288 | } | |
2289 | ||
2290 | ||
2291 | /* return socket to remote host, port */ | |
396c147e | 2292 | static int |
01794848 | 2293 | connect_to(const char *host, u_short port) |
8efc0c15 | 2294 | { |
48e671d5 | 2295 | struct addrinfo hints, *ai, *aitop; |
2296 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; | |
2297 | int gaierr; | |
7368a6c8 | 2298 | int sock = -1; |
48e671d5 | 2299 | |
2300 | memset(&hints, 0, sizeof(hints)); | |
2301 | hints.ai_family = IPv4or6; | |
2302 | hints.ai_socktype = SOCK_STREAM; | |
01794848 | 2303 | snprintf(strport, sizeof strport, "%d", port); |
48e671d5 | 2304 | if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) { |
01794848 | 2305 | error("connect_to %.100s: unknown host (%s)", host, |
2306 | gai_strerror(gaierr)); | |
7368a6c8 | 2307 | return -1; |
48e671d5 | 2308 | } |
48e671d5 | 2309 | for (ai = aitop; ai; ai = ai->ai_next) { |
2310 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2311 | continue; | |
2312 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), | |
2313 | strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
01794848 | 2314 | error("connect_to: getnameinfo failed"); |
48e671d5 | 2315 | continue; |
5260325f | 2316 | } |
48e671d5 | 2317 | sock = socket(ai->ai_family, SOCK_STREAM, 0); |
2318 | if (sock < 0) { | |
2319 | error("socket: %.100s", strerror(errno)); | |
2320 | continue; | |
5260325f | 2321 | } |
eea39c02 | 2322 | if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0) |
97fb6912 | 2323 | fatal("connect_to: F_SETFL: %s", strerror(errno)); |
97fb6912 | 2324 | if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 && |
2325 | errno != EINPROGRESS) { | |
01794848 | 2326 | error("connect_to %.100s port %s: %.100s", ntop, strport, |
48e671d5 | 2327 | strerror(errno)); |
2328 | close(sock); | |
2b87da3b | 2329 | continue; /* fail -- try next */ |
48e671d5 | 2330 | } |
2331 | break; /* success */ | |
5260325f | 2332 | |
5260325f | 2333 | } |
48e671d5 | 2334 | freeaddrinfo(aitop); |
48e671d5 | 2335 | if (!ai) { |
01794848 | 2336 | error("connect_to %.100s port %d: failed.", host, port); |
7368a6c8 | 2337 | return -1; |
8efc0c15 | 2338 | } |
7368a6c8 | 2339 | /* success */ |
2340 | return sock; | |
2341 | } | |
01794848 | 2342 | |
fa08c86b | 2343 | int |
b3f8a79c | 2344 | channel_connect_by_listen_address(u_short listen_port) |
fa08c86b | 2345 | { |
2346 | int i; | |
01794848 | 2347 | |
fa08c86b | 2348 | for (i = 0; i < num_permitted_opens; i++) |
2349 | if (permitted_opens[i].listen_port == listen_port) | |
01794848 | 2350 | return connect_to( |
fa08c86b | 2351 | permitted_opens[i].host_to_connect, |
2352 | permitted_opens[i].port_to_connect); | |
0b6fbf03 | 2353 | error("WARNING: Server requests forwarding for unknown listen_port %d", |
2354 | listen_port); | |
fa08c86b | 2355 | return -1; |
2356 | } | |
48e671d5 | 2357 | |
01794848 | 2358 | /* Check if connecting to that port is permitted and connect. */ |
2359 | int | |
2360 | channel_connect_to(const char *host, u_short port) | |
2361 | { | |
2362 | int i, permit; | |
2363 | ||
2364 | permit = all_opens_permitted; | |
2365 | if (!permit) { | |
2366 | for (i = 0; i < num_permitted_opens; i++) | |
2367 | if (permitted_opens[i].port_to_connect == port && | |
2368 | strcmp(permitted_opens[i].host_to_connect, host) == 0) | |
2369 | permit = 1; | |
2370 | ||
2371 | } | |
2372 | if (!permit) { | |
2373 | log("Received request to connect to host %.100s port %d, " | |
2374 | "but the request was denied.", host, port); | |
2375 | return -1; | |
2376 | } | |
2377 | return connect_to(host, port); | |
2378 | } | |
2379 | ||
8e7895b8 | 2380 | /* -- X11 forwarding */ |
8efc0c15 | 2381 | |
aa3378df | 2382 | /* |
2383 | * Creates an internet domain socket for listening for X11 connections. | |
c9d0ad9b | 2384 | * Returns a suitable display number for the DISPLAY variable, or -1 if |
2385 | * an error occurs. | |
aa3378df | 2386 | */ |
c9d0ad9b | 2387 | int |
ac151b18 | 2388 | x11_create_display_inet(int x11_display_offset, int gateway_ports, |
2389 | int single_connection) | |
8efc0c15 | 2390 | { |
ac151b18 | 2391 | Channel *nc = NULL; |
57112b5a | 2392 | int display_number, sock; |
2393 | u_short port; | |
48e671d5 | 2394 | struct addrinfo hints, *ai, *aitop; |
2395 | char strport[NI_MAXSERV]; | |
2396 | int gaierr, n, num_socks = 0, socks[NUM_SOCKS]; | |
5260325f | 2397 | |
95f1eccc | 2398 | for (display_number = x11_display_offset; |
184eed6a | 2399 | display_number < MAX_DISPLAYS; |
2400 | display_number++) { | |
5260325f | 2401 | port = 6000 + display_number; |
48e671d5 | 2402 | memset(&hints, 0, sizeof(hints)); |
2403 | hints.ai_family = IPv4or6; | |
c9d0ad9b | 2404 | hints.ai_flags = gateway_ports ? AI_PASSIVE : 0; |
48e671d5 | 2405 | hints.ai_socktype = SOCK_STREAM; |
2406 | snprintf(strport, sizeof strport, "%d", port); | |
2407 | if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) { | |
2408 | error("getaddrinfo: %.100s", gai_strerror(gaierr)); | |
c9d0ad9b | 2409 | return -1; |
5260325f | 2410 | } |
48e671d5 | 2411 | for (ai = aitop; ai; ai = ai->ai_next) { |
2412 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2413 | continue; | |
2414 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
2415 | if (sock < 0) { | |
4ee81249 | 2416 | if ((errno != EINVAL) && (errno != EAFNOSUPPORT)) { |
80a44451 | 2417 | error("socket: %.100s", strerror(errno)); |
c9d0ad9b | 2418 | return -1; |
80a44451 | 2419 | } else { |
22d89d24 | 2420 | debug("x11_create_display_inet: Socket family %d not supported", |
2421 | ai->ai_family); | |
80a44451 | 2422 | continue; |
2423 | } | |
48e671d5 | 2424 | } |
2425 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
2426 | debug("bind port %d: %.100s", port, strerror(errno)); | |
48e671d5 | 2427 | close(sock); |
16218745 | 2428 | |
2429 | if (ai->ai_next) | |
2430 | continue; | |
2431 | ||
48e671d5 | 2432 | for (n = 0; n < num_socks; n++) { |
48e671d5 | 2433 | close(socks[n]); |
2434 | } | |
2435 | num_socks = 0; | |
2436 | break; | |
2437 | } | |
2438 | socks[num_socks++] = sock; | |
80faa19f | 2439 | #ifndef DONT_TRY_OTHER_AF |
48e671d5 | 2440 | if (num_socks == NUM_SOCKS) |
2441 | break; | |
80faa19f | 2442 | #else |
2443 | break; | |
2444 | #endif | |
5260325f | 2445 | } |
4ccb01d6 | 2446 | freeaddrinfo(aitop); |
48e671d5 | 2447 | if (num_socks > 0) |
2448 | break; | |
5260325f | 2449 | } |
2450 | if (display_number >= MAX_DISPLAYS) { | |
2451 | error("Failed to allocate internet-domain X11 display socket."); | |
c9d0ad9b | 2452 | return -1; |
8efc0c15 | 2453 | } |
5260325f | 2454 | /* Start listening for connections on the socket. */ |
48e671d5 | 2455 | for (n = 0; n < num_socks; n++) { |
2456 | sock = socks[n]; | |
2457 | if (listen(sock, 5) < 0) { | |
2458 | error("listen: %.100s", strerror(errno)); | |
48e671d5 | 2459 | close(sock); |
c9d0ad9b | 2460 | return -1; |
a7effaac | 2461 | } |
a7effaac | 2462 | } |
5260325f | 2463 | |
48e671d5 | 2464 | /* Allocate a channel for each socket. */ |
2465 | for (n = 0; n < num_socks; n++) { | |
2466 | sock = socks[n]; | |
ac151b18 | 2467 | nc = channel_new("x11 listener", |
0b242b12 | 2468 | SSH_CHANNEL_X11_LISTENER, sock, sock, -1, |
2469 | CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, | |
a22aff1f | 2470 | 0, xstrdup("X11 inet listener"), 1); |
ac151b18 | 2471 | if (nc != NULL) |
2472 | nc->single_connection = single_connection; | |
48e671d5 | 2473 | } |
5260325f | 2474 | |
c9d0ad9b | 2475 | /* Return the display number for the DISPLAY environment variable. */ |
2476 | return display_number; | |
8efc0c15 | 2477 | } |
2478 | ||
396c147e | 2479 | static int |
1e3b8b07 | 2480 | connect_local_xsocket(u_int dnr) |
8efc0c15 | 2481 | { |
5260325f | 2482 | int sock; |
2483 | struct sockaddr_un addr; | |
5260325f | 2484 | |
805e659f | 2485 | sock = socket(AF_UNIX, SOCK_STREAM, 0); |
2486 | if (sock < 0) | |
2487 | error("socket: %.100s", strerror(errno)); | |
2488 | memset(&addr, 0, sizeof(addr)); | |
2489 | addr.sun_family = AF_UNIX; | |
2490 | snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr); | |
2491 | if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0) | |
2492 | return sock; | |
2493 | close(sock); | |
5260325f | 2494 | error("connect %.100s: %.100s", addr.sun_path, strerror(errno)); |
2495 | return -1; | |
8efc0c15 | 2496 | } |
2497 | ||
0b242b12 | 2498 | int |
2499 | x11_connect_display(void) | |
8efc0c15 | 2500 | { |
d24631c9 | 2501 | int display_number, sock = 0, on = 1; |
5260325f | 2502 | const char *display; |
0b242b12 | 2503 | char buf[1024], *cp; |
48e671d5 | 2504 | struct addrinfo hints, *ai, *aitop; |
2505 | char strport[NI_MAXSERV]; | |
2506 | int gaierr; | |
5260325f | 2507 | |
5260325f | 2508 | /* Try to open a socket for the local X server. */ |
2509 | display = getenv("DISPLAY"); | |
2510 | if (!display) { | |
2511 | error("DISPLAY not set."); | |
0b242b12 | 2512 | return -1; |
5260325f | 2513 | } |
aa3378df | 2514 | /* |
2515 | * Now we decode the value of the DISPLAY variable and make a | |
2516 | * connection to the real X server. | |
2517 | */ | |
2518 | ||
2519 | /* | |
2520 | * Check if it is a unix domain socket. Unix domain displays are in | |
2521 | * one of the following formats: unix:d[.s], :d[.s], ::d[.s] | |
2522 | */ | |
5260325f | 2523 | if (strncmp(display, "unix:", 5) == 0 || |
2524 | display[0] == ':') { | |
2525 | /* Connect to the unix domain socket. */ | |
2526 | if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) { | |
2527 | error("Could not parse display number from DISPLAY: %.100s", | |
184eed6a | 2528 | display); |
0b242b12 | 2529 | return -1; |
5260325f | 2530 | } |
2531 | /* Create a socket. */ | |
2532 | sock = connect_local_xsocket(display_number); | |
2533 | if (sock < 0) | |
0b242b12 | 2534 | return -1; |
5260325f | 2535 | |
2536 | /* OK, we now have a connection to the display. */ | |
0b242b12 | 2537 | return sock; |
5260325f | 2538 | } |
aa3378df | 2539 | /* |
2540 | * Connect to an inet socket. The DISPLAY value is supposedly | |
2541 | * hostname:d[.s], where hostname may also be numeric IP address. | |
2542 | */ | |
74860245 | 2543 | strlcpy(buf, display, sizeof(buf)); |
5260325f | 2544 | cp = strchr(buf, ':'); |
2545 | if (!cp) { | |
2546 | error("Could not find ':' in DISPLAY: %.100s", display); | |
0b242b12 | 2547 | return -1; |
5260325f | 2548 | } |
2549 | *cp = 0; | |
aa3378df | 2550 | /* buf now contains the host name. But first we parse the display number. */ |
5260325f | 2551 | if (sscanf(cp + 1, "%d", &display_number) != 1) { |
2552 | error("Could not parse display number from DISPLAY: %.100s", | |
184eed6a | 2553 | display); |
0b242b12 | 2554 | return -1; |
5260325f | 2555 | } |
5260325f | 2556 | |
48e671d5 | 2557 | /* Look up the host address */ |
2558 | memset(&hints, 0, sizeof(hints)); | |
2559 | hints.ai_family = IPv4or6; | |
2560 | hints.ai_socktype = SOCK_STREAM; | |
2561 | snprintf(strport, sizeof strport, "%d", 6000 + display_number); | |
2562 | if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) { | |
2563 | error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr)); | |
0b242b12 | 2564 | return -1; |
8efc0c15 | 2565 | } |
48e671d5 | 2566 | for (ai = aitop; ai; ai = ai->ai_next) { |
2567 | /* Create a socket. */ | |
2568 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
2569 | if (sock < 0) { | |
2570 | debug("socket: %.100s", strerror(errno)); | |
7368a6c8 | 2571 | continue; |
2572 | } | |
2573 | /* Connect it to the display. */ | |
2574 | if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
2575 | debug("connect %.100s port %d: %.100s", buf, | |
2576 | 6000 + display_number, strerror(errno)); | |
2577 | close(sock); | |
2578 | continue; | |
2579 | } | |
2580 | /* Success */ | |
2581 | break; | |
48e671d5 | 2582 | } |
48e671d5 | 2583 | freeaddrinfo(aitop); |
2584 | if (!ai) { | |
6ae2364d | 2585 | error("connect %.100s port %d: %.100s", buf, 6000 + display_number, |
48e671d5 | 2586 | strerror(errno)); |
0b242b12 | 2587 | return -1; |
8efc0c15 | 2588 | } |
d24631c9 | 2589 | if (setsockopt(sock, IPPROTO_TCP, TCP_NODELAY, &on, sizeof on) == -1) |
2590 | error("setsockopt TCP_NODELAY: %.100s", strerror(errno)); | |
0b242b12 | 2591 | return sock; |
2592 | } | |
5260325f | 2593 | |
0b242b12 | 2594 | /* |
2595 | * This is called when SSH_SMSG_X11_OPEN is received. The packet contains | |
2596 | * the remote channel number. We should do whatever we want, and respond | |
2597 | * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE. | |
2598 | */ | |
5260325f | 2599 | |
0b242b12 | 2600 | void |
7819b5c3 | 2601 | x11_input_open(int type, u_int32_t seq, void *ctxt) |
0b242b12 | 2602 | { |
719fc62f | 2603 | Channel *c = NULL; |
2604 | int remote_id, sock = 0; | |
0b242b12 | 2605 | char *remote_host; |
5260325f | 2606 | |
719fc62f | 2607 | debug("Received X11 open request."); |
5260325f | 2608 | |
719fc62f | 2609 | remote_id = packet_get_int(); |
8e7895b8 | 2610 | |
2611 | if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) { | |
719fc62f | 2612 | remote_host = packet_get_string(NULL); |
0b242b12 | 2613 | } else { |
2614 | remote_host = xstrdup("unknown (remote did not supply name)"); | |
0b242b12 | 2615 | } |
95500969 | 2616 | packet_check_eom(); |
0b242b12 | 2617 | |
2618 | /* Obtain a connection to the real X display. */ | |
2619 | sock = x11_connect_display(); | |
719fc62f | 2620 | if (sock != -1) { |
2621 | /* Allocate a channel for this connection. */ | |
2622 | c = channel_new("connected x11 socket", | |
2623 | SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0, | |
2624 | remote_host, 1); | |
2625 | if (c == NULL) { | |
2626 | error("x11_input_open: channel_new failed"); | |
2627 | close(sock); | |
2628 | } else { | |
2629 | c->remote_id = remote_id; | |
a5f82435 | 2630 | c->force_drain = 1; |
719fc62f | 2631 | } |
2632 | } | |
2633 | if (c == NULL) { | |
0b242b12 | 2634 | /* Send refusal to the remote host. */ |
2635 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
719fc62f | 2636 | packet_put_int(remote_id); |
0b242b12 | 2637 | } else { |
0b242b12 | 2638 | /* Send a confirmation to the remote host. */ |
2639 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
719fc62f | 2640 | packet_put_int(remote_id); |
2641 | packet_put_int(c->self); | |
0b242b12 | 2642 | } |
719fc62f | 2643 | packet_send(); |
8efc0c15 | 2644 | } |
2645 | ||
a22aff1f | 2646 | /* dummy protocol handler that denies SSH-1 requests (agent/x11) */ |
2647 | void | |
7819b5c3 | 2648 | deny_input_open(int type, u_int32_t seq, void *ctxt) |
a22aff1f | 2649 | { |
2650 | int rchan = packet_get_int(); | |
6aacefa7 | 2651 | switch (type) { |
a22aff1f | 2652 | case SSH_SMSG_AGENT_OPEN: |
2653 | error("Warning: ssh server tried agent forwarding."); | |
2654 | break; | |
2655 | case SSH_SMSG_X11_OPEN: | |
2656 | error("Warning: ssh server tried X11 forwarding."); | |
2657 | break; | |
2658 | default: | |
7819b5c3 | 2659 | error("deny_input_open: type %d", type); |
a22aff1f | 2660 | break; |
2661 | } | |
2662 | error("Warning: this is probably a break in attempt by a malicious server."); | |
2663 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
2664 | packet_put_int(rchan); | |
2665 | packet_send(); | |
2666 | } | |
2667 | ||
aa3378df | 2668 | /* |
2669 | * Requests forwarding of X11 connections, generates fake authentication | |
2670 | * data, and enables authentication spoofing. | |
8e7895b8 | 2671 | * This should be called in the client only. |
aa3378df | 2672 | */ |
6ae2364d | 2673 | void |
0b242b12 | 2674 | x11_request_forwarding_with_spoofing(int client_session_id, |
2675 | const char *proto, const char *data) | |
8efc0c15 | 2676 | { |
1e3b8b07 | 2677 | u_int data_len = (u_int) strlen(data) / 2; |
ca910e13 | 2678 | u_int i, value, len; |
5260325f | 2679 | char *new_data; |
2680 | int screen_number; | |
2681 | const char *cp; | |
2682 | u_int32_t rand = 0; | |
2683 | ||
2684 | cp = getenv("DISPLAY"); | |
2685 | if (cp) | |
2686 | cp = strchr(cp, ':'); | |
2687 | if (cp) | |
2688 | cp = strchr(cp, '.'); | |
2689 | if (cp) | |
2690 | screen_number = atoi(cp + 1); | |
2691 | else | |
2692 | screen_number = 0; | |
2693 | ||
2694 | /* Save protocol name. */ | |
2695 | x11_saved_proto = xstrdup(proto); | |
2696 | ||
aa3378df | 2697 | /* |
2698 | * Extract real authentication data and generate fake data of the | |
2699 | * same length. | |
2700 | */ | |
5260325f | 2701 | x11_saved_data = xmalloc(data_len); |
2702 | x11_fake_data = xmalloc(data_len); | |
2703 | for (i = 0; i < data_len; i++) { | |
2704 | if (sscanf(data + 2 * i, "%2x", &value) != 1) | |
2705 | fatal("x11_request_forwarding: bad authentication data: %.100s", data); | |
2706 | if (i % 4 == 0) | |
2707 | rand = arc4random(); | |
2708 | x11_saved_data[i] = value; | |
2709 | x11_fake_data[i] = rand & 0xff; | |
2710 | rand >>= 8; | |
2711 | } | |
2712 | x11_saved_data_len = data_len; | |
2713 | x11_fake_data_len = data_len; | |
2714 | ||
2715 | /* Convert the fake data into hex. */ | |
ca910e13 | 2716 | len = 2 * data_len + 1; |
2717 | new_data = xmalloc(len); | |
5260325f | 2718 | for (i = 0; i < data_len; i++) |
ca910e13 | 2719 | snprintf(new_data + 2 * i, len - 2 * i, |
2720 | "%02x", (u_char) x11_fake_data[i]); | |
5260325f | 2721 | |
2722 | /* Send the request packet. */ | |
0b242b12 | 2723 | if (compat20) { |
2724 | channel_request_start(client_session_id, "x11-req", 0); | |
2725 | packet_put_char(0); /* XXX bool single connection */ | |
2726 | } else { | |
2727 | packet_start(SSH_CMSG_X11_REQUEST_FORWARDING); | |
2728 | } | |
2729 | packet_put_cstring(proto); | |
2730 | packet_put_cstring(new_data); | |
5260325f | 2731 | packet_put_int(screen_number); |
2732 | packet_send(); | |
2733 | packet_write_wait(); | |
2734 | xfree(new_data); | |
8efc0c15 | 2735 | } |
2736 | ||
8e7895b8 | 2737 | |
2738 | /* -- agent forwarding */ | |
2739 | ||
8efc0c15 | 2740 | /* Sends a message to the server to request authentication fd forwarding. */ |
2741 | ||
6ae2364d | 2742 | void |
d5bb9418 | 2743 | auth_request_forwarding(void) |
8efc0c15 | 2744 | { |
5260325f | 2745 | packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING); |
2746 | packet_send(); | |
2747 | packet_write_wait(); | |
8efc0c15 | 2748 | } |
2749 | ||
aa3378df | 2750 | /* |
2751 | * Returns the name of the forwarded authentication socket. Returns NULL if | |
2752 | * there is no forwarded authentication socket. The returned value points to | |
2753 | * a static buffer. | |
2754 | */ | |
8efc0c15 | 2755 | |
5260325f | 2756 | char * |
d5bb9418 | 2757 | auth_get_socket_name(void) |
8efc0c15 | 2758 | { |
8e7895b8 | 2759 | return auth_sock_name; |
8efc0c15 | 2760 | } |
2761 | ||
2762 | /* removes the agent forwarding socket */ | |
2763 | ||
6ae2364d | 2764 | void |
f0f32b8e | 2765 | auth_sock_cleanup_proc(void *_pw) |
5260325f | 2766 | { |
f0f32b8e | 2767 | struct passwd *pw = _pw; |
2768 | ||
e4f7282d | 2769 | if (auth_sock_name) { |
f0f32b8e | 2770 | temporarily_use_uid(pw); |
e4f7282d | 2771 | unlink(auth_sock_name); |
2772 | rmdir(auth_sock_dir); | |
2773 | auth_sock_name = NULL; | |
f0f32b8e | 2774 | restore_uid(); |
e4f7282d | 2775 | } |
8efc0c15 | 2776 | } |
2777 | ||
aa3378df | 2778 | /* |
fa649821 | 2779 | * This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server. |
aa3378df | 2780 | * This starts forwarding authentication requests. |
2781 | */ | |
8efc0c15 | 2782 | |
fa649821 | 2783 | int |
5260325f | 2784 | auth_input_request_forwarding(struct passwd * pw) |
8efc0c15 | 2785 | { |
719fc62f | 2786 | Channel *nc; |
2787 | int sock; | |
5260325f | 2788 | struct sockaddr_un sunaddr; |
2789 | ||
8e7895b8 | 2790 | if (auth_get_socket_name() != NULL) { |
2791 | error("authentication forwarding requested twice."); | |
2792 | return 0; | |
2793 | } | |
5260325f | 2794 | |
2795 | /* Temporarily drop privileged uid for mkdir/bind. */ | |
63bd8c36 | 2796 | temporarily_use_uid(pw); |
5260325f | 2797 | |
2798 | /* Allocate a buffer for the socket name, and format the name. */ | |
8e7895b8 | 2799 | auth_sock_name = xmalloc(MAXPATHLEN); |
2800 | auth_sock_dir = xmalloc(MAXPATHLEN); | |
2801 | strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXX", MAXPATHLEN); | |
5260325f | 2802 | |
2803 | /* Create private directory for socket */ | |
8e7895b8 | 2804 | if (mkdtemp(auth_sock_dir) == NULL) { |
2805 | packet_send_debug("Agent forwarding disabled: " | |
2806 | "mkdtemp() failed: %.100s", strerror(errno)); | |
fa649821 | 2807 | restore_uid(); |
8e7895b8 | 2808 | xfree(auth_sock_name); |
2809 | xfree(auth_sock_dir); | |
2810 | auth_sock_name = NULL; | |
2811 | auth_sock_dir = NULL; | |
fa649821 | 2812 | return 0; |
2813 | } | |
8e7895b8 | 2814 | snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%d", |
2815 | auth_sock_dir, (int) getpid()); | |
5260325f | 2816 | |
e4f7282d | 2817 | /* delete agent socket on fatal() */ |
f0f32b8e | 2818 | fatal_add_cleanup(auth_sock_cleanup_proc, pw); |
e4f7282d | 2819 | |
5260325f | 2820 | /* Create the socket. */ |
2821 | sock = socket(AF_UNIX, SOCK_STREAM, 0); | |
2822 | if (sock < 0) | |
2823 | packet_disconnect("socket: %.100s", strerror(errno)); | |
2824 | ||
2825 | /* Bind it to the name. */ | |
2826 | memset(&sunaddr, 0, sizeof(sunaddr)); | |
2827 | sunaddr.sun_family = AF_UNIX; | |
74860245 | 2828 | strlcpy(sunaddr.sun_path, auth_sock_name, sizeof(sunaddr.sun_path)); |
5260325f | 2829 | |
2830 | if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) | |
2831 | packet_disconnect("bind: %.100s", strerror(errno)); | |
2832 | ||
2833 | /* Restore the privileged uid. */ | |
2834 | restore_uid(); | |
2835 | ||
2836 | /* Start listening on the socket. */ | |
2837 | if (listen(sock, 5) < 0) | |
2838 | packet_disconnect("listen: %.100s", strerror(errno)); | |
2839 | ||
2840 | /* Allocate a channel for the authentication agent socket. */ | |
719fc62f | 2841 | nc = channel_new("auth socket", |
fa08c86b | 2842 | SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1, |
2843 | CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, | |
2844 | 0, xstrdup("auth socket"), 1); | |
719fc62f | 2845 | if (nc == NULL) { |
2846 | error("auth_input_request_forwarding: channel_new failed"); | |
f0f32b8e | 2847 | auth_sock_cleanup_proc(pw); |
750c256a | 2848 | fatal_remove_cleanup(auth_sock_cleanup_proc, pw); |
719fc62f | 2849 | close(sock); |
2850 | return 0; | |
2851 | } | |
8e7895b8 | 2852 | strlcpy(nc->path, auth_sock_name, sizeof(nc->path)); |
fa649821 | 2853 | return 1; |
8efc0c15 | 2854 | } |
2855 | ||
2856 | /* This is called to process an SSH_SMSG_AGENT_OPEN message. */ | |
2857 | ||
6ae2364d | 2858 | void |
7819b5c3 | 2859 | auth_input_open_request(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 2860 | { |
719fc62f | 2861 | Channel *c = NULL; |
2862 | int remote_id, sock; | |
8e7895b8 | 2863 | char *name; |
5260325f | 2864 | |
2865 | /* Read the remote channel number from the message. */ | |
719fc62f | 2866 | remote_id = packet_get_int(); |
95500969 | 2867 | packet_check_eom(); |
5260325f | 2868 | |
aa3378df | 2869 | /* |
2870 | * Get a connection to the local authentication agent (this may again | |
2871 | * get forwarded). | |
2872 | */ | |
5260325f | 2873 | sock = ssh_get_authentication_socket(); |
2874 | ||
aa3378df | 2875 | /* |
2876 | * If we could not connect the agent, send an error message back to | |
2877 | * the server. This should never happen unless the agent dies, | |
2878 | * because authentication forwarding is only enabled if we have an | |
2879 | * agent. | |
2880 | */ | |
719fc62f | 2881 | if (sock >= 0) { |
8e7895b8 | 2882 | name = xstrdup("authentication agent connection"); |
2883 | c = channel_new("", SSH_CHANNEL_OPEN, sock, sock, | |
2884 | -1, 0, 0, 0, name, 1); | |
719fc62f | 2885 | if (c == NULL) { |
2886 | error("auth_input_open_request: channel_new failed"); | |
8e7895b8 | 2887 | xfree(name); |
719fc62f | 2888 | close(sock); |
2889 | } else { | |
2890 | c->remote_id = remote_id; | |
a5f82435 | 2891 | c->force_drain = 1; |
719fc62f | 2892 | } |
2893 | } | |
2894 | if (c == NULL) { | |
5260325f | 2895 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); |
719fc62f | 2896 | packet_put_int(remote_id); |
2897 | } else { | |
2898 | /* Send a confirmation to the remote host. */ | |
2899 | debug("Forwarding authentication connection."); | |
2900 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
2901 | packet_put_int(remote_id); | |
2902 | packet_put_int(c->self); | |
5260325f | 2903 | } |
5260325f | 2904 | packet_send(); |
8efc0c15 | 2905 | } |