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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" | |
e1feb9bf | 42 | RCSID("$OpenBSD: channels.c,v 1.180 2002/07/04 08:12:15 deraadt 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" | |
42f11eb2 | 49 | #include "log.h" |
50 | #include "misc.h" | |
8efc0c15 | 51 | #include "channels.h" |
8efc0c15 | 52 | #include "compat.h" |
42f11eb2 | 53 | #include "canohost.h" |
4c8722d9 | 54 | #include "key.h" |
55 | #include "authfd.h" | |
805e659f | 56 | #include "pathnames.h" |
7e7327a1 | 57 | |
8efc0c15 | 58 | |
8e7895b8 | 59 | /* -- channel core */ |
8efc0c15 | 60 | |
aa3378df | 61 | /* |
62 | * Pointer to an array containing all allocated channels. The array is | |
63 | * dynamically extended as needed. | |
64 | */ | |
719fc62f | 65 | static Channel **channels = NULL; |
8efc0c15 | 66 | |
aa3378df | 67 | /* |
68 | * Size of the channel array. All slots of the array must always be | |
719fc62f | 69 | * initialized (at least the type field); unused slots set to NULL |
aa3378df | 70 | */ |
8efc0c15 | 71 | static int channels_alloc = 0; |
72 | ||
aa3378df | 73 | /* |
74 | * Maximum file descriptor value used in any of the channels. This is | |
719fc62f | 75 | * updated in channel_new. |
aa3378df | 76 | */ |
39929cdb | 77 | static int channel_max_fd = 0; |
8efc0c15 | 78 | |
8efc0c15 | 79 | |
8e7895b8 | 80 | /* -- tcp forwarding */ |
8efc0c15 | 81 | |
aa3378df | 82 | /* |
83 | * Data structure for storing which hosts are permitted for forward requests. | |
84 | * The local sides of any remote forwards are stored in this array to prevent | |
85 | * a corrupt remote server from accessing arbitrary TCP/IP ports on our local | |
86 | * network (which might be behind a firewall). | |
87 | */ | |
5260325f | 88 | typedef struct { |
7368a6c8 | 89 | char *host_to_connect; /* Connect to 'host'. */ |
90 | u_short port_to_connect; /* Connect to 'port'. */ | |
91 | u_short listen_port; /* Remote side should listen port number. */ | |
8efc0c15 | 92 | } ForwardPermission; |
93 | ||
94 | /* List of all permitted host/port pairs to connect. */ | |
95 | static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION]; | |
8e7895b8 | 96 | |
8efc0c15 | 97 | /* Number of permitted host/port pairs in the array. */ |
98 | static int num_permitted_opens = 0; | |
aa3378df | 99 | /* |
100 | * If this is true, all opens are permitted. This is the case on the server | |
101 | * on which we have to trust the client anyway, and the user could do | |
102 | * anything after logging in anyway. | |
103 | */ | |
8efc0c15 | 104 | static int all_opens_permitted = 0; |
105 | ||
8efc0c15 | 106 | |
8e7895b8 | 107 | /* -- X11 forwarding */ |
42f11eb2 | 108 | |
8e7895b8 | 109 | /* Maximum number of fake X11 displays to try. */ |
110 | #define MAX_DISPLAYS 1000 | |
0490e609 | 111 | |
8e7895b8 | 112 | /* Saved X11 authentication protocol name. */ |
113 | static char *x11_saved_proto = NULL; | |
8efc0c15 | 114 | |
8e7895b8 | 115 | /* Saved X11 authentication data. This is the real data. */ |
116 | static char *x11_saved_data = NULL; | |
117 | static u_int x11_saved_data_len = 0; | |
118 | ||
119 | /* | |
120 | * Fake X11 authentication data. This is what the server will be sending us; | |
121 | * we should replace any occurrences of this by the real data. | |
122 | */ | |
123 | static char *x11_fake_data = NULL; | |
124 | static u_int x11_fake_data_len; | |
125 | ||
126 | ||
127 | /* -- agent forwarding */ | |
8efc0c15 | 128 | |
8e7895b8 | 129 | #define NUM_SOCKS 10 |
130 | ||
8e7895b8 | 131 | /* AF_UNSPEC or AF_INET or AF_INET6 */ |
5e4a7219 | 132 | static int IPv4or6 = AF_UNSPEC; |
8e7895b8 | 133 | |
134 | /* helper */ | |
396c147e | 135 | static void port_open_helper(Channel *c, char *rtype); |
8e7895b8 | 136 | |
137 | /* -- channel core */ | |
7368a6c8 | 138 | |
139 | Channel * | |
140 | channel_lookup(int id) | |
141 | { | |
142 | Channel *c; | |
719fc62f | 143 | |
c77d2e56 | 144 | if (id < 0 || id >= channels_alloc) { |
7368a6c8 | 145 | log("channel_lookup: %d: bad id", id); |
146 | return NULL; | |
147 | } | |
719fc62f | 148 | c = channels[id]; |
149 | if (c == NULL) { | |
7368a6c8 | 150 | log("channel_lookup: %d: bad id: channel free", id); |
151 | return NULL; | |
152 | } | |
153 | return c; | |
154 | } | |
155 | ||
aa3378df | 156 | /* |
1d1ffb87 | 157 | * Register filedescriptors for a channel, used when allocating a channel or |
0fbe8c74 | 158 | * when the channel consumer/producer is ready, e.g. shell exec'd |
aa3378df | 159 | */ |
8efc0c15 | 160 | |
396c147e | 161 | static void |
a22aff1f | 162 | channel_register_fds(Channel *c, int rfd, int wfd, int efd, |
163 | int extusage, int nonblock) | |
8efc0c15 | 164 | { |
5260325f | 165 | /* Update the maximum file descriptor value. */ |
39929cdb | 166 | channel_max_fd = MAX(channel_max_fd, rfd); |
167 | channel_max_fd = MAX(channel_max_fd, wfd); | |
168 | channel_max_fd = MAX(channel_max_fd, efd); | |
169 | ||
aa3378df | 170 | /* XXX set close-on-exec -markus */ |
1d1ffb87 | 171 | |
0fbe8c74 | 172 | c->rfd = rfd; |
173 | c->wfd = wfd; | |
174 | c->sock = (rfd == wfd) ? rfd : -1; | |
175 | c->efd = efd; | |
176 | c->extended_usage = extusage; | |
a22aff1f | 177 | |
0ae4fe1d | 178 | /* XXX ugly hack: nonblock is only set by the server */ |
179 | if (nonblock && isatty(c->rfd)) { | |
94dfb550 | 180 | debug("channel %d: rfd %d isatty", c->self, c->rfd); |
0ae4fe1d | 181 | c->isatty = 1; |
182 | if (!isatty(c->wfd)) { | |
94dfb550 | 183 | error("channel %d: wfd %d is not a tty?", |
0ae4fe1d | 184 | c->self, c->wfd); |
185 | } | |
186 | } else { | |
187 | c->isatty = 0; | |
188 | } | |
189 | ||
a22aff1f | 190 | /* enable nonblocking mode */ |
191 | if (nonblock) { | |
192 | if (rfd != -1) | |
193 | set_nonblock(rfd); | |
194 | if (wfd != -1) | |
195 | set_nonblock(wfd); | |
196 | if (efd != -1) | |
197 | set_nonblock(efd); | |
198 | } | |
0fbe8c74 | 199 | } |
200 | ||
201 | /* | |
202 | * Allocate a new channel object and set its type and socket. This will cause | |
203 | * remote_name to be freed. | |
204 | */ | |
205 | ||
719fc62f | 206 | Channel * |
0fbe8c74 | 207 | channel_new(char *ctype, int type, int rfd, int wfd, int efd, |
f91d9a89 | 208 | u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock) |
0fbe8c74 | 209 | { |
210 | int i, found; | |
211 | Channel *c; | |
5260325f | 212 | |
213 | /* Do initial allocation if this is the first call. */ | |
214 | if (channels_alloc == 0) { | |
215 | channels_alloc = 10; | |
719fc62f | 216 | channels = xmalloc(channels_alloc * sizeof(Channel *)); |
5260325f | 217 | for (i = 0; i < channels_alloc; i++) |
719fc62f | 218 | channels[i] = NULL; |
d6746a0b | 219 | fatal_add_cleanup((void (*) (void *)) channel_free_all, NULL); |
5260325f | 220 | } |
221 | /* Try to find a free slot where to put the new channel. */ | |
222 | for (found = -1, i = 0; i < channels_alloc; i++) | |
719fc62f | 223 | if (channels[i] == NULL) { |
5260325f | 224 | /* Found a free slot. */ |
225 | found = i; | |
226 | break; | |
227 | } | |
228 | if (found == -1) { | |
aa3378df | 229 | /* There are no free slots. Take last+1 slot and expand the array. */ |
5260325f | 230 | found = channels_alloc; |
231 | channels_alloc += 10; | |
5df8c731 | 232 | if (channels_alloc > 10000) |
233 | fatal("channel_new: internal error: channels_alloc %d " | |
234 | "too big.", channels_alloc); | |
de273eef | 235 | debug2("channel: expanding %d", channels_alloc); |
719fc62f | 236 | channels = xrealloc(channels, channels_alloc * sizeof(Channel *)); |
5260325f | 237 | for (i = found; i < channels_alloc; i++) |
719fc62f | 238 | channels[i] = NULL; |
5260325f | 239 | } |
719fc62f | 240 | /* Initialize and return new channel. */ |
241 | c = channels[found] = xmalloc(sizeof(Channel)); | |
639cb8ab | 242 | memset(c, 0, sizeof(Channel)); |
5260325f | 243 | buffer_init(&c->input); |
244 | buffer_init(&c->output); | |
7368a6c8 | 245 | buffer_init(&c->extended); |
70bef40e | 246 | c->ostate = CHAN_OUTPUT_OPEN; |
247 | c->istate = CHAN_INPUT_OPEN; | |
248 | c->flags = 0; | |
a22aff1f | 249 | channel_register_fds(c, rfd, wfd, efd, extusage, nonblock); |
5260325f | 250 | c->self = found; |
251 | c->type = type; | |
7368a6c8 | 252 | c->ctype = ctype; |
0b242b12 | 253 | c->local_window = window; |
254 | c->local_window_max = window; | |
255 | c->local_consumed = 0; | |
256 | c->local_maxpacket = maxpack; | |
5260325f | 257 | c->remote_id = -1; |
258 | c->remote_name = remote_name; | |
7368a6c8 | 259 | c->remote_window = 0; |
260 | c->remote_maxpacket = 0; | |
a5f82435 | 261 | c->force_drain = 0; |
ac151b18 | 262 | c->single_connection = 0; |
3cf2be58 | 263 | c->detach_user = NULL; |
05ca0898 | 264 | c->confirm = NULL; |
2e73a022 | 265 | c->input_filter = NULL; |
5260325f | 266 | debug("channel %d: new [%s]", found, remote_name); |
719fc62f | 267 | return c; |
7368a6c8 | 268 | } |
8efc0c15 | 269 | |
489aa2e9 | 270 | static int |
271 | channel_find_maxfd(void) | |
272 | { | |
273 | int i, max = 0; | |
274 | Channel *c; | |
275 | ||
276 | for (i = 0; i < channels_alloc; i++) { | |
277 | c = channels[i]; | |
278 | if (c != NULL) { | |
279 | max = MAX(max, c->rfd); | |
280 | max = MAX(max, c->wfd); | |
281 | max = MAX(max, c->efd); | |
282 | } | |
283 | } | |
284 | return max; | |
285 | } | |
286 | ||
287 | int | |
288 | channel_close_fd(int *fdp) | |
289 | { | |
290 | int ret = 0, fd = *fdp; | |
291 | ||
292 | if (fd != -1) { | |
293 | ret = close(fd); | |
294 | *fdp = -1; | |
295 | if (fd == channel_max_fd) | |
296 | channel_max_fd = channel_find_maxfd(); | |
297 | } | |
298 | return ret; | |
299 | } | |
300 | ||
0fbe8c74 | 301 | /* Close all channel fd/socket. */ |
302 | ||
396c147e | 303 | static void |
0fbe8c74 | 304 | channel_close_fds(Channel *c) |
305 | { | |
6fd8622b | 306 | debug3("channel_close_fds: channel %d: r %d w %d e %d", |
307 | c->self, c->rfd, c->wfd, c->efd); | |
308 | ||
489aa2e9 | 309 | channel_close_fd(&c->sock); |
310 | channel_close_fd(&c->rfd); | |
311 | channel_close_fd(&c->wfd); | |
312 | channel_close_fd(&c->efd); | |
0fbe8c74 | 313 | } |
314 | ||
8e7895b8 | 315 | /* Free the channel and close its fd/socket. */ |
316 | ||
317 | void | |
318 | channel_free(Channel *c) | |
319 | { | |
320 | char *s; | |
321 | int i, n; | |
322 | ||
323 | for (n = 0, i = 0; i < channels_alloc; i++) | |
324 | if (channels[i]) | |
325 | n++; | |
326 | debug("channel_free: channel %d: %s, nchannels %d", c->self, | |
327 | c->remote_name ? c->remote_name : "???", n); | |
328 | ||
329 | s = channel_open_message(); | |
330 | debug3("channel_free: status: %s", s); | |
331 | xfree(s); | |
332 | ||
8e7895b8 | 333 | if (c->sock != -1) |
334 | shutdown(c->sock, SHUT_RDWR); | |
335 | channel_close_fds(c); | |
336 | buffer_free(&c->input); | |
337 | buffer_free(&c->output); | |
338 | buffer_free(&c->extended); | |
339 | if (c->remote_name) { | |
340 | xfree(c->remote_name); | |
341 | c->remote_name = NULL; | |
342 | } | |
343 | channels[c->self] = NULL; | |
344 | xfree(c); | |
345 | } | |
346 | ||
8e7895b8 | 347 | void |
d6746a0b | 348 | channel_free_all(void) |
8e7895b8 | 349 | { |
350 | int i; | |
8e7895b8 | 351 | |
d6746a0b | 352 | for (i = 0; i < channels_alloc; i++) |
353 | if (channels[i] != NULL) | |
354 | channel_free(channels[i]); | |
8e7895b8 | 355 | } |
356 | ||
357 | /* | |
358 | * Closes the sockets/fds of all channels. This is used to close extra file | |
359 | * descriptors after a fork. | |
360 | */ | |
361 | ||
362 | void | |
d5bb9418 | 363 | channel_close_all(void) |
8e7895b8 | 364 | { |
365 | int i; | |
366 | ||
367 | for (i = 0; i < channels_alloc; i++) | |
368 | if (channels[i] != NULL) | |
369 | channel_close_fds(channels[i]); | |
370 | } | |
371 | ||
3cf2be58 | 372 | /* |
373 | * Stop listening to channels. | |
374 | */ | |
375 | ||
376 | void | |
377 | channel_stop_listening(void) | |
378 | { | |
379 | int i; | |
380 | Channel *c; | |
381 | ||
382 | for (i = 0; i < channels_alloc; i++) { | |
383 | c = channels[i]; | |
384 | if (c != NULL) { | |
385 | switch (c->type) { | |
386 | case SSH_CHANNEL_AUTH_SOCKET: | |
387 | case SSH_CHANNEL_PORT_LISTENER: | |
388 | case SSH_CHANNEL_RPORT_LISTENER: | |
389 | case SSH_CHANNEL_X11_LISTENER: | |
489aa2e9 | 390 | channel_close_fd(&c->sock); |
3cf2be58 | 391 | channel_free(c); |
392 | break; | |
393 | } | |
394 | } | |
395 | } | |
396 | } | |
397 | ||
8e7895b8 | 398 | /* |
399 | * Returns true if no channel has too much buffered data, and false if one or | |
400 | * more channel is overfull. | |
401 | */ | |
402 | ||
403 | int | |
d5bb9418 | 404 | channel_not_very_much_buffered_data(void) |
8e7895b8 | 405 | { |
406 | u_int i; | |
407 | Channel *c; | |
408 | ||
409 | for (i = 0; i < channels_alloc; i++) { | |
410 | c = channels[i]; | |
411 | if (c != NULL && c->type == SSH_CHANNEL_OPEN) { | |
0c139bd1 | 412 | #if 0 |
413 | if (!compat20 && | |
414 | buffer_len(&c->input) > packet_get_maxsize()) { | |
8e7895b8 | 415 | debug("channel %d: big input buffer %d", |
416 | c->self, buffer_len(&c->input)); | |
417 | return 0; | |
418 | } | |
0c139bd1 | 419 | #endif |
8e7895b8 | 420 | if (buffer_len(&c->output) > packet_get_maxsize()) { |
0c139bd1 | 421 | debug("channel %d: big output buffer %d > %d", |
422 | c->self, buffer_len(&c->output), | |
423 | packet_get_maxsize()); | |
8e7895b8 | 424 | return 0; |
425 | } | |
426 | } | |
427 | } | |
428 | return 1; | |
429 | } | |
430 | ||
431 | /* Returns true if any channel is still open. */ | |
432 | ||
433 | int | |
d5bb9418 | 434 | channel_still_open(void) |
8e7895b8 | 435 | { |
436 | int i; | |
437 | Channel *c; | |
438 | ||
439 | for (i = 0; i < channels_alloc; i++) { | |
440 | c = channels[i]; | |
441 | if (c == NULL) | |
442 | continue; | |
443 | switch (c->type) { | |
444 | case SSH_CHANNEL_X11_LISTENER: | |
445 | case SSH_CHANNEL_PORT_LISTENER: | |
446 | case SSH_CHANNEL_RPORT_LISTENER: | |
447 | case SSH_CHANNEL_CLOSED: | |
448 | case SSH_CHANNEL_AUTH_SOCKET: | |
449 | case SSH_CHANNEL_DYNAMIC: | |
450 | case SSH_CHANNEL_CONNECTING: | |
451 | case SSH_CHANNEL_ZOMBIE: | |
452 | continue; | |
453 | case SSH_CHANNEL_LARVAL: | |
454 | if (!compat20) | |
455 | fatal("cannot happen: SSH_CHANNEL_LARVAL"); | |
456 | continue; | |
457 | case SSH_CHANNEL_OPENING: | |
458 | case SSH_CHANNEL_OPEN: | |
459 | case SSH_CHANNEL_X11_OPEN: | |
460 | return 1; | |
461 | case SSH_CHANNEL_INPUT_DRAINING: | |
462 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
463 | if (!compat13) | |
464 | fatal("cannot happen: OUT_DRAIN"); | |
465 | return 1; | |
466 | default: | |
467 | fatal("channel_still_open: bad channel type %d", c->type); | |
468 | /* NOTREACHED */ | |
469 | } | |
470 | } | |
471 | return 0; | |
472 | } | |
473 | ||
474 | /* Returns the id of an open channel suitable for keepaliving */ | |
475 | ||
476 | int | |
d5bb9418 | 477 | channel_find_open(void) |
8e7895b8 | 478 | { |
479 | int i; | |
480 | Channel *c; | |
481 | ||
482 | for (i = 0; i < channels_alloc; i++) { | |
483 | c = channels[i]; | |
484 | if (c == NULL) | |
485 | continue; | |
486 | switch (c->type) { | |
487 | case SSH_CHANNEL_CLOSED: | |
488 | case SSH_CHANNEL_DYNAMIC: | |
489 | case SSH_CHANNEL_X11_LISTENER: | |
490 | case SSH_CHANNEL_PORT_LISTENER: | |
491 | case SSH_CHANNEL_RPORT_LISTENER: | |
492 | case SSH_CHANNEL_OPENING: | |
493 | case SSH_CHANNEL_CONNECTING: | |
494 | case SSH_CHANNEL_ZOMBIE: | |
495 | continue; | |
496 | case SSH_CHANNEL_LARVAL: | |
497 | case SSH_CHANNEL_AUTH_SOCKET: | |
498 | case SSH_CHANNEL_OPEN: | |
499 | case SSH_CHANNEL_X11_OPEN: | |
500 | return i; | |
501 | case SSH_CHANNEL_INPUT_DRAINING: | |
502 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
503 | if (!compat13) | |
504 | fatal("cannot happen: OUT_DRAIN"); | |
505 | return i; | |
506 | default: | |
507 | fatal("channel_find_open: bad channel type %d", c->type); | |
508 | /* NOTREACHED */ | |
509 | } | |
510 | } | |
511 | return -1; | |
512 | } | |
513 | ||
514 | ||
515 | /* | |
516 | * Returns a message describing the currently open forwarded connections, | |
517 | * suitable for sending to the client. The message contains crlf pairs for | |
518 | * newlines. | |
519 | */ | |
520 | ||
521 | char * | |
d5bb9418 | 522 | channel_open_message(void) |
8e7895b8 | 523 | { |
524 | Buffer buffer; | |
525 | Channel *c; | |
526 | char buf[1024], *cp; | |
527 | int i; | |
528 | ||
529 | buffer_init(&buffer); | |
530 | snprintf(buf, sizeof buf, "The following connections are open:\r\n"); | |
531 | buffer_append(&buffer, buf, strlen(buf)); | |
532 | for (i = 0; i < channels_alloc; i++) { | |
533 | c = channels[i]; | |
534 | if (c == NULL) | |
535 | continue; | |
536 | switch (c->type) { | |
537 | case SSH_CHANNEL_X11_LISTENER: | |
538 | case SSH_CHANNEL_PORT_LISTENER: | |
539 | case SSH_CHANNEL_RPORT_LISTENER: | |
540 | case SSH_CHANNEL_CLOSED: | |
541 | case SSH_CHANNEL_AUTH_SOCKET: | |
542 | case SSH_CHANNEL_ZOMBIE: | |
543 | continue; | |
544 | case SSH_CHANNEL_LARVAL: | |
545 | case SSH_CHANNEL_OPENING: | |
546 | case SSH_CHANNEL_CONNECTING: | |
547 | case SSH_CHANNEL_DYNAMIC: | |
548 | case SSH_CHANNEL_OPEN: | |
549 | case SSH_CHANNEL_X11_OPEN: | |
550 | case SSH_CHANNEL_INPUT_DRAINING: | |
551 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
552 | snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n", | |
553 | c->self, c->remote_name, | |
554 | c->type, c->remote_id, | |
555 | c->istate, buffer_len(&c->input), | |
556 | c->ostate, buffer_len(&c->output), | |
557 | c->rfd, c->wfd); | |
558 | buffer_append(&buffer, buf, strlen(buf)); | |
559 | continue; | |
560 | default: | |
561 | fatal("channel_open_message: bad channel type %d", c->type); | |
562 | /* NOTREACHED */ | |
563 | } | |
564 | } | |
565 | buffer_append(&buffer, "\0", 1); | |
566 | cp = xstrdup(buffer_ptr(&buffer)); | |
567 | buffer_free(&buffer); | |
568 | return cp; | |
569 | } | |
570 | ||
571 | void | |
572 | channel_send_open(int id) | |
573 | { | |
574 | Channel *c = channel_lookup(id); | |
e1feb9bf | 575 | |
8e7895b8 | 576 | if (c == NULL) { |
577 | log("channel_send_open: %d: bad id", id); | |
578 | return; | |
579 | } | |
580 | debug("send channel open %d", id); | |
581 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
582 | packet_put_cstring(c->ctype); | |
583 | packet_put_int(c->self); | |
584 | packet_put_int(c->local_window); | |
585 | packet_put_int(c->local_maxpacket); | |
586 | packet_send(); | |
587 | } | |
588 | ||
589 | void | |
06ee33fb | 590 | channel_request_start(int local_id, char *service, int wantconfirm) |
8e7895b8 | 591 | { |
06ee33fb | 592 | Channel *c = channel_lookup(local_id); |
e1feb9bf | 593 | |
8e7895b8 | 594 | if (c == NULL) { |
06ee33fb | 595 | log("channel_request_start: %d: unknown channel id", local_id); |
8e7895b8 | 596 | return; |
597 | } | |
06ee33fb | 598 | debug("channel request %d: %s", local_id, service) ; |
8e7895b8 | 599 | packet_start(SSH2_MSG_CHANNEL_REQUEST); |
600 | packet_put_int(c->remote_id); | |
601 | packet_put_cstring(service); | |
602 | packet_put_char(wantconfirm); | |
603 | } | |
604 | void | |
05ca0898 | 605 | channel_register_confirm(int id, channel_callback_fn *fn) |
8e7895b8 | 606 | { |
607 | Channel *c = channel_lookup(id); | |
e1feb9bf | 608 | |
8e7895b8 | 609 | if (c == NULL) { |
05ca0898 | 610 | log("channel_register_comfirm: %d: bad id", id); |
8e7895b8 | 611 | return; |
612 | } | |
05ca0898 | 613 | c->confirm = fn; |
8e7895b8 | 614 | } |
615 | void | |
616 | channel_register_cleanup(int id, channel_callback_fn *fn) | |
617 | { | |
618 | Channel *c = channel_lookup(id); | |
e1feb9bf | 619 | |
8e7895b8 | 620 | if (c == NULL) { |
621 | log("channel_register_cleanup: %d: bad id", id); | |
622 | return; | |
623 | } | |
3cf2be58 | 624 | c->detach_user = fn; |
8e7895b8 | 625 | } |
626 | void | |
627 | channel_cancel_cleanup(int id) | |
628 | { | |
629 | Channel *c = channel_lookup(id); | |
e1feb9bf | 630 | |
8e7895b8 | 631 | if (c == NULL) { |
632 | log("channel_cancel_cleanup: %d: bad id", id); | |
633 | return; | |
634 | } | |
3cf2be58 | 635 | c->detach_user = NULL; |
8e7895b8 | 636 | } |
637 | void | |
638 | channel_register_filter(int id, channel_filter_fn *fn) | |
639 | { | |
640 | Channel *c = channel_lookup(id); | |
e1feb9bf | 641 | |
8e7895b8 | 642 | if (c == NULL) { |
643 | log("channel_register_filter: %d: bad id", id); | |
644 | return; | |
645 | } | |
646 | c->input_filter = fn; | |
647 | } | |
648 | ||
6ae2364d | 649 | void |
8e7895b8 | 650 | channel_set_fds(int id, int rfd, int wfd, int efd, |
399d1ea6 | 651 | int extusage, int nonblock, u_int window_max) |
8efc0c15 | 652 | { |
8e7895b8 | 653 | Channel *c = channel_lookup(id); |
e1feb9bf | 654 | |
8e7895b8 | 655 | if (c == NULL || c->type != SSH_CHANNEL_LARVAL) |
656 | fatal("channel_activate for non-larval channel %d.", id); | |
657 | channel_register_fds(c, rfd, wfd, efd, extusage, nonblock); | |
658 | c->type = SSH_CHANNEL_OPEN; | |
399d1ea6 | 659 | c->local_window = c->local_window_max = window_max; |
8e7895b8 | 660 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); |
661 | packet_put_int(c->remote_id); | |
662 | packet_put_int(c->local_window); | |
663 | packet_send(); | |
8efc0c15 | 664 | } |
665 | ||
aa3378df | 666 | /* |
7368a6c8 | 667 | * 'channel_pre*' are called just before select() to add any bits relevant to |
668 | * channels in the select bitmasks. | |
aa3378df | 669 | */ |
7368a6c8 | 670 | /* |
671 | * 'channel_post*': perform any appropriate operations for channels which | |
672 | * have events pending. | |
673 | */ | |
674 | typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset); | |
675 | chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE]; | |
676 | chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE]; | |
8efc0c15 | 677 | |
396c147e | 678 | static void |
7368a6c8 | 679 | channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset) |
8efc0c15 | 680 | { |
7368a6c8 | 681 | FD_SET(c->sock, readset); |
682 | } | |
5260325f | 683 | |
396c147e | 684 | static void |
97fb6912 | 685 | channel_pre_connecting(Channel *c, fd_set * readset, fd_set * writeset) |
686 | { | |
687 | debug3("channel %d: waiting for connection", c->self); | |
688 | FD_SET(c->sock, writeset); | |
689 | } | |
690 | ||
396c147e | 691 | static void |
7368a6c8 | 692 | channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset) |
693 | { | |
694 | if (buffer_len(&c->input) < packet_get_maxsize()) | |
695 | FD_SET(c->sock, readset); | |
696 | if (buffer_len(&c->output) > 0) | |
697 | FD_SET(c->sock, writeset); | |
698 | } | |
5260325f | 699 | |
396c147e | 700 | static void |
0c0738d5 | 701 | channel_pre_open(Channel *c, fd_set * readset, fd_set * writeset) |
7368a6c8 | 702 | { |
0c0738d5 | 703 | u_int limit = compat20 ? c->remote_window : packet_get_maxsize(); |
5260325f | 704 | |
7e7327a1 | 705 | if (c->istate == CHAN_INPUT_OPEN && |
0c0738d5 | 706 | limit > 0 && |
707 | buffer_len(&c->input) < limit) | |
7e7327a1 | 708 | FD_SET(c->rfd, readset); |
709 | if (c->ostate == CHAN_OUTPUT_OPEN || | |
710 | c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
711 | if (buffer_len(&c->output) > 0) { | |
712 | FD_SET(c->wfd, writeset); | |
713 | } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
d2296ed7 | 714 | if (CHANNEL_EFD_OUTPUT_ACTIVE(c)) |
875ec275 | 715 | debug2("channel %d: obuf_empty delayed efd %d/(%d)", |
716 | c->self, c->efd, buffer_len(&c->extended)); | |
d2296ed7 | 717 | else |
718 | chan_obuf_empty(c); | |
7e7327a1 | 719 | } |
720 | } | |
721 | /** XXX check close conditions, too */ | |
0c0738d5 | 722 | if (compat20 && c->efd != -1) { |
7e7327a1 | 723 | if (c->extended_usage == CHAN_EXTENDED_WRITE && |
724 | buffer_len(&c->extended) > 0) | |
725 | FD_SET(c->efd, writeset); | |
d2296ed7 | 726 | else if (!(c->flags & CHAN_EOF_SENT) && |
727 | c->extended_usage == CHAN_EXTENDED_READ && | |
7e7327a1 | 728 | buffer_len(&c->extended) < c->remote_window) |
729 | FD_SET(c->efd, readset); | |
730 | } | |
731 | } | |
732 | ||
396c147e | 733 | static void |
7368a6c8 | 734 | channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset) |
735 | { | |
736 | if (buffer_len(&c->input) == 0) { | |
737 | packet_start(SSH_MSG_CHANNEL_CLOSE); | |
738 | packet_put_int(c->remote_id); | |
739 | packet_send(); | |
740 | c->type = SSH_CHANNEL_CLOSED; | |
070adba2 | 741 | debug("channel %d: closing after input drain.", c->self); |
7368a6c8 | 742 | } |
743 | } | |
5260325f | 744 | |
396c147e | 745 | static void |
7368a6c8 | 746 | channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset) |
747 | { | |
748 | if (buffer_len(&c->output) == 0) | |
719fc62f | 749 | chan_mark_dead(c); |
6ae2364d | 750 | else |
7368a6c8 | 751 | FD_SET(c->sock, writeset); |
752 | } | |
5260325f | 753 | |
7368a6c8 | 754 | /* |
755 | * This is a special state for X11 authentication spoofing. An opened X11 | |
756 | * connection (when authentication spoofing is being done) remains in this | |
757 | * state until the first packet has been completely read. The authentication | |
758 | * data in that packet is then substituted by the real data if it matches the | |
759 | * fake data, and the channel is put into normal mode. | |
0b242b12 | 760 | * XXX All this happens at the client side. |
8e7895b8 | 761 | * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok |
7368a6c8 | 762 | */ |
396c147e | 763 | static int |
8e7895b8 | 764 | x11_open_helper(Buffer *b) |
7368a6c8 | 765 | { |
1e3b8b07 | 766 | u_char *ucp; |
767 | u_int proto_len, data_len; | |
5260325f | 768 | |
7368a6c8 | 769 | /* Check if the fixed size part of the packet is in buffer. */ |
8e7895b8 | 770 | if (buffer_len(b) < 12) |
7368a6c8 | 771 | return 0; |
772 | ||
773 | /* Parse the lengths of variable-length fields. */ | |
20905a8e | 774 | ucp = buffer_ptr(b); |
7368a6c8 | 775 | if (ucp[0] == 0x42) { /* Byte order MSB first. */ |
776 | proto_len = 256 * ucp[6] + ucp[7]; | |
777 | data_len = 256 * ucp[8] + ucp[9]; | |
778 | } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */ | |
779 | proto_len = ucp[6] + 256 * ucp[7]; | |
780 | data_len = ucp[8] + 256 * ucp[9]; | |
781 | } else { | |
782 | debug("Initial X11 packet contains bad byte order byte: 0x%x", | |
184eed6a | 783 | ucp[0]); |
7368a6c8 | 784 | return -1; |
785 | } | |
5260325f | 786 | |
7368a6c8 | 787 | /* Check if the whole packet is in buffer. */ |
8e7895b8 | 788 | if (buffer_len(b) < |
7368a6c8 | 789 | 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3)) |
790 | return 0; | |
5260325f | 791 | |
7368a6c8 | 792 | /* Check if authentication protocol matches. */ |
793 | if (proto_len != strlen(x11_saved_proto) || | |
794 | memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) { | |
795 | debug("X11 connection uses different authentication protocol."); | |
796 | return -1; | |
797 | } | |
798 | /* Check if authentication data matches our fake data. */ | |
799 | if (data_len != x11_fake_data_len || | |
800 | memcmp(ucp + 12 + ((proto_len + 3) & ~3), | |
801 | x11_fake_data, x11_fake_data_len) != 0) { | |
802 | debug("X11 auth data does not match fake data."); | |
803 | return -1; | |
804 | } | |
805 | /* Check fake data length */ | |
806 | if (x11_fake_data_len != x11_saved_data_len) { | |
807 | error("X11 fake_data_len %d != saved_data_len %d", | |
808 | x11_fake_data_len, x11_saved_data_len); | |
809 | return -1; | |
810 | } | |
811 | /* | |
812 | * Received authentication protocol and data match | |
813 | * our fake data. Substitute the fake data with real | |
814 | * data. | |
815 | */ | |
816 | memcpy(ucp + 12 + ((proto_len + 3) & ~3), | |
817 | x11_saved_data, x11_saved_data_len); | |
818 | return 1; | |
819 | } | |
5260325f | 820 | |
396c147e | 821 | static void |
7368a6c8 | 822 | channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset) |
823 | { | |
8e7895b8 | 824 | int ret = x11_open_helper(&c->output); |
e1feb9bf | 825 | |
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; |
bcc0381e | 989 | int newsock; |
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 | } |
bcc0381e | 1007 | set_nodelay(newsock); |
865ac82e | 1008 | remote_ipaddr = get_peer_ipaddr(newsock); |
0b242b12 | 1009 | remote_port = get_peer_port(newsock); |
7368a6c8 | 1010 | snprintf(buf, sizeof buf, "X11 connection from %.200s port %d", |
865ac82e | 1011 | remote_ipaddr, remote_port); |
0b242b12 | 1012 | |
719fc62f | 1013 | nc = channel_new("accepted x11 socket", |
0b242b12 | 1014 | SSH_CHANNEL_OPENING, newsock, newsock, -1, |
1015 | c->local_window_max, c->local_maxpacket, | |
a22aff1f | 1016 | 0, xstrdup(buf), 1); |
0b242b12 | 1017 | if (compat20) { |
1018 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
1019 | packet_put_cstring("x11"); | |
719fc62f | 1020 | packet_put_int(nc->self); |
ac151b18 | 1021 | packet_put_int(nc->local_window_max); |
1022 | packet_put_int(nc->local_maxpacket); | |
865ac82e | 1023 | /* originator ipaddr and port */ |
1024 | packet_put_cstring(remote_ipaddr); | |
d0c832f3 | 1025 | if (datafellows & SSH_BUG_X11FWD) { |
1026 | debug("ssh2 x11 bug compat mode"); | |
1027 | } else { | |
1028 | packet_put_int(remote_port); | |
1029 | } | |
0b242b12 | 1030 | packet_send(); |
1031 | } else { | |
1032 | packet_start(SSH_SMSG_X11_OPEN); | |
719fc62f | 1033 | packet_put_int(nc->self); |
8e7895b8 | 1034 | if (packet_get_protocol_flags() & |
1035 | SSH_PROTOFLAG_HOST_IN_FWD_OPEN) | |
449c5ba5 | 1036 | packet_put_cstring(buf); |
0b242b12 | 1037 | packet_send(); |
1038 | } | |
865ac82e | 1039 | xfree(remote_ipaddr); |
8efc0c15 | 1040 | } |
8efc0c15 | 1041 | } |
1042 | ||
396c147e | 1043 | static void |
0490e609 | 1044 | port_open_helper(Channel *c, char *rtype) |
1045 | { | |
1046 | int direct; | |
1047 | char buf[1024]; | |
1048 | char *remote_ipaddr = get_peer_ipaddr(c->sock); | |
1049 | u_short remote_port = get_peer_port(c->sock); | |
1050 | ||
1051 | direct = (strcmp(rtype, "direct-tcpip") == 0); | |
1052 | ||
1053 | snprintf(buf, sizeof buf, | |
1054 | "%s: listening port %d for %.100s port %d, " | |
1055 | "connect from %.200s port %d", | |
1056 | rtype, c->listening_port, c->path, c->host_port, | |
1057 | remote_ipaddr, remote_port); | |
1058 | ||
1059 | xfree(c->remote_name); | |
1060 | c->remote_name = xstrdup(buf); | |
1061 | ||
1062 | if (compat20) { | |
1063 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
1064 | packet_put_cstring(rtype); | |
1065 | packet_put_int(c->self); | |
1066 | packet_put_int(c->local_window_max); | |
1067 | packet_put_int(c->local_maxpacket); | |
1068 | if (direct) { | |
1069 | /* target host, port */ | |
1070 | packet_put_cstring(c->path); | |
1071 | packet_put_int(c->host_port); | |
1072 | } else { | |
1073 | /* listen address, port */ | |
1074 | packet_put_cstring(c->path); | |
1075 | packet_put_int(c->listening_port); | |
1076 | } | |
1077 | /* originator host and port */ | |
1078 | packet_put_cstring(remote_ipaddr); | |
1079 | packet_put_int(remote_port); | |
1080 | packet_send(); | |
1081 | } else { | |
1082 | packet_start(SSH_MSG_PORT_OPEN); | |
1083 | packet_put_int(c->self); | |
1084 | packet_put_cstring(c->path); | |
1085 | packet_put_int(c->host_port); | |
8e7895b8 | 1086 | if (packet_get_protocol_flags() & |
1087 | SSH_PROTOFLAG_HOST_IN_FWD_OPEN) | |
0490e609 | 1088 | packet_put_cstring(c->remote_name); |
1089 | packet_send(); | |
1090 | } | |
1091 | xfree(remote_ipaddr); | |
1092 | } | |
1093 | ||
aa3378df | 1094 | /* |
7368a6c8 | 1095 | * This socket is listening for connections to a forwarded TCP/IP port. |
aa3378df | 1096 | */ |
396c147e | 1097 | static void |
7368a6c8 | 1098 | channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset) |
1099 | { | |
0490e609 | 1100 | Channel *nc; |
7368a6c8 | 1101 | struct sockaddr addr; |
719fc62f | 1102 | int newsock, nextstate; |
7368a6c8 | 1103 | socklen_t addrlen; |
0490e609 | 1104 | char *rtype; |
fa08c86b | 1105 | |
7368a6c8 | 1106 | if (FD_ISSET(c->sock, readset)) { |
1107 | debug("Connection to port %d forwarding " | |
1108 | "to %.100s port %d requested.", | |
1109 | c->listening_port, c->path, c->host_port); | |
0490e609 | 1110 | |
639cb8ab | 1111 | if (c->type == SSH_CHANNEL_RPORT_LISTENER) { |
1112 | nextstate = SSH_CHANNEL_OPENING; | |
1113 | rtype = "forwarded-tcpip"; | |
1114 | } else { | |
1115 | if (c->host_port == 0) { | |
1116 | nextstate = SSH_CHANNEL_DYNAMIC; | |
f3964cb9 | 1117 | rtype = "dynamic-tcpip"; |
639cb8ab | 1118 | } else { |
1119 | nextstate = SSH_CHANNEL_OPENING; | |
1120 | rtype = "direct-tcpip"; | |
1121 | } | |
1122 | } | |
0490e609 | 1123 | |
7368a6c8 | 1124 | addrlen = sizeof(addr); |
1125 | newsock = accept(c->sock, &addr, &addrlen); | |
1126 | if (newsock < 0) { | |
1127 | error("accept: %.100s", strerror(errno)); | |
1128 | return; | |
1129 | } | |
811a6342 | 1130 | set_nodelay(newsock); |
719fc62f | 1131 | nc = channel_new(rtype, |
0490e609 | 1132 | nextstate, newsock, newsock, -1, |
7368a6c8 | 1133 | c->local_window_max, c->local_maxpacket, |
0490e609 | 1134 | 0, xstrdup(rtype), 1); |
0490e609 | 1135 | nc->listening_port = c->listening_port; |
1136 | nc->host_port = c->host_port; | |
1137 | strlcpy(nc->path, c->path, sizeof(nc->path)); | |
1138 | ||
639cb8ab | 1139 | if (nextstate == SSH_CHANNEL_DYNAMIC) { |
1140 | /* | |
1141 | * do not call the channel_post handler until | |
1142 | * this flag has been reset by a pre-handler. | |
1143 | * otherwise the FD_ISSET calls might overflow | |
1144 | */ | |
1145 | nc->delayed = 1; | |
1146 | } else { | |
0490e609 | 1147 | port_open_helper(nc, rtype); |
639cb8ab | 1148 | } |
7368a6c8 | 1149 | } |
1150 | } | |
8efc0c15 | 1151 | |
7368a6c8 | 1152 | /* |
1153 | * This is the authentication agent socket listening for connections from | |
1154 | * clients. | |
1155 | */ | |
396c147e | 1156 | static void |
7368a6c8 | 1157 | channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset) |
8efc0c15 | 1158 | { |
719fc62f | 1159 | Channel *nc; |
8e7895b8 | 1160 | char *name; |
719fc62f | 1161 | int newsock; |
5260325f | 1162 | struct sockaddr addr; |
48e671d5 | 1163 | socklen_t addrlen; |
5260325f | 1164 | |
7368a6c8 | 1165 | if (FD_ISSET(c->sock, readset)) { |
1166 | addrlen = sizeof(addr); | |
1167 | newsock = accept(c->sock, &addr, &addrlen); | |
1168 | if (newsock < 0) { | |
1169 | error("accept from auth socket: %.100s", strerror(errno)); | |
1170 | return; | |
1171 | } | |
8e7895b8 | 1172 | name = xstrdup("accepted auth socket"); |
719fc62f | 1173 | nc = channel_new("accepted auth socket", |
fa08c86b | 1174 | SSH_CHANNEL_OPENING, newsock, newsock, -1, |
1175 | c->local_window_max, c->local_maxpacket, | |
8e7895b8 | 1176 | 0, name, 1); |
fa08c86b | 1177 | if (compat20) { |
1178 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
1179 | packet_put_cstring("auth-agent@openssh.com"); | |
719fc62f | 1180 | packet_put_int(nc->self); |
fa08c86b | 1181 | packet_put_int(c->local_window_max); |
1182 | packet_put_int(c->local_maxpacket); | |
1183 | } else { | |
1184 | packet_start(SSH_SMSG_AGENT_OPEN); | |
719fc62f | 1185 | packet_put_int(nc->self); |
fa08c86b | 1186 | } |
7368a6c8 | 1187 | packet_send(); |
1188 | } | |
1189 | } | |
5260325f | 1190 | |
396c147e | 1191 | static void |
97fb6912 | 1192 | channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset) |
1193 | { | |
d18e0850 | 1194 | int err = 0; |
8ab2cb35 | 1195 | socklen_t sz = sizeof(err); |
d18e0850 | 1196 | |
97fb6912 | 1197 | if (FD_ISSET(c->sock, writeset)) { |
db518d9b | 1198 | if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) { |
d18e0850 | 1199 | err = errno; |
1200 | error("getsockopt SO_ERROR failed"); | |
1201 | } | |
1202 | if (err == 0) { | |
1203 | debug("channel %d: connected", c->self); | |
1204 | c->type = SSH_CHANNEL_OPEN; | |
1205 | if (compat20) { | |
1206 | packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1207 | packet_put_int(c->remote_id); | |
1208 | packet_put_int(c->self); | |
1209 | packet_put_int(c->local_window); | |
1210 | packet_put_int(c->local_maxpacket); | |
1211 | } else { | |
1212 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1213 | packet_put_int(c->remote_id); | |
1214 | packet_put_int(c->self); | |
1215 | } | |
97fb6912 | 1216 | } else { |
d18e0850 | 1217 | debug("channel %d: not connected: %s", |
1218 | c->self, strerror(err)); | |
1219 | if (compat20) { | |
1220 | packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE); | |
1221 | packet_put_int(c->remote_id); | |
1222 | packet_put_int(SSH2_OPEN_CONNECT_FAILED); | |
1223 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { | |
1224 | packet_put_cstring(strerror(err)); | |
1225 | packet_put_cstring(""); | |
1226 | } | |
97fb6912 | 1227 | } else { |
d18e0850 | 1228 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); |
1229 | packet_put_int(c->remote_id); | |
97fb6912 | 1230 | } |
d18e0850 | 1231 | chan_mark_dead(c); |
97fb6912 | 1232 | } |
d18e0850 | 1233 | packet_send(); |
97fb6912 | 1234 | } |
1235 | } | |
1236 | ||
396c147e | 1237 | static int |
7368a6c8 | 1238 | channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset) |
1239 | { | |
1240 | char buf[16*1024]; | |
1241 | int len; | |
1242 | ||
6fd8622b | 1243 | if (c->rfd != -1 && |
7368a6c8 | 1244 | FD_ISSET(c->rfd, readset)) { |
1245 | len = read(c->rfd, buf, sizeof(buf)); | |
0fbe8c74 | 1246 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1247 | return 1; | |
7368a6c8 | 1248 | if (len <= 0) { |
0b242b12 | 1249 | debug("channel %d: read<=0 rfd %d len %d", |
7368a6c8 | 1250 | c->self, c->rfd, len); |
28b9cb4d | 1251 | if (c->type != SSH_CHANNEL_OPEN) { |
1252 | debug("channel %d: not open", c->self); | |
719fc62f | 1253 | chan_mark_dead(c); |
0490e609 | 1254 | return -1; |
28b9cb4d | 1255 | } else if (compat13) { |
9c50edcf | 1256 | buffer_clear(&c->output); |
7368a6c8 | 1257 | c->type = SSH_CHANNEL_INPUT_DRAINING; |
8e7895b8 | 1258 | debug("channel %d: input draining.", c->self); |
7368a6c8 | 1259 | } else { |
1260 | chan_read_failed(c); | |
5260325f | 1261 | } |
7368a6c8 | 1262 | return -1; |
1263 | } | |
6aacefa7 | 1264 | if (c->input_filter != NULL) { |
2e73a022 | 1265 | if (c->input_filter(c, buf, len) == -1) { |
070adba2 | 1266 | debug("channel %d: filter stops", c->self); |
2e73a022 | 1267 | chan_read_failed(c); |
1268 | } | |
1269 | } else { | |
1270 | buffer_append(&c->input, buf, len); | |
1271 | } | |
7368a6c8 | 1272 | } |
1273 | return 1; | |
1274 | } | |
396c147e | 1275 | static int |
7368a6c8 | 1276 | channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset) |
1277 | { | |
95ce5599 | 1278 | struct termios tio; |
780a9951 | 1279 | u_char *data; |
1280 | u_int dlen; | |
7368a6c8 | 1281 | int len; |
1282 | ||
1283 | /* Send buffered output data to the socket. */ | |
6fd8622b | 1284 | if (c->wfd != -1 && |
7368a6c8 | 1285 | FD_ISSET(c->wfd, writeset) && |
1286 | buffer_len(&c->output) > 0) { | |
780a9951 | 1287 | data = buffer_ptr(&c->output); |
1288 | dlen = buffer_len(&c->output); | |
1289 | len = write(c->wfd, data, dlen); | |
64c0ce80 | 1290 | #ifdef _AIX |
1291 | /* XXX: Later AIX versions can't push as much data to tty */ | |
1292 | if (compat20 && c->isatty && dlen >= 8*1024) | |
1293 | dlen = 8*1024; | |
1294 | #endif | |
0fbe8c74 | 1295 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1296 | return 1; | |
7368a6c8 | 1297 | if (len <= 0) { |
28b9cb4d | 1298 | if (c->type != SSH_CHANNEL_OPEN) { |
1299 | debug("channel %d: not open", c->self); | |
719fc62f | 1300 | chan_mark_dead(c); |
28b9cb4d | 1301 | return -1; |
1302 | } else if (compat13) { | |
9c50edcf | 1303 | buffer_clear(&c->output); |
8e7895b8 | 1304 | debug("channel %d: input draining.", c->self); |
7368a6c8 | 1305 | c->type = SSH_CHANNEL_INPUT_DRAINING; |
1306 | } else { | |
1307 | chan_write_failed(c); | |
5260325f | 1308 | } |
7368a6c8 | 1309 | return -1; |
1310 | } | |
780a9951 | 1311 | if (compat20 && c->isatty && dlen >= 1 && data[0] != '\r') { |
0ae4fe1d | 1312 | if (tcgetattr(c->wfd, &tio) == 0 && |
1313 | !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) { | |
1314 | /* | |
1315 | * Simulate echo to reduce the impact of | |
355724fc | 1316 | * traffic analysis. We need to match the |
95ce5599 | 1317 | * size of a SSH2_MSG_CHANNEL_DATA message |
1318 | * (4 byte channel id + data) | |
0ae4fe1d | 1319 | */ |
95ce5599 | 1320 | packet_send_ignore(4 + len); |
0ae4fe1d | 1321 | packet_send(); |
0ae4fe1d | 1322 | } |
1323 | } | |
7368a6c8 | 1324 | buffer_consume(&c->output, len); |
7e7327a1 | 1325 | if (compat20 && len > 0) { |
1326 | c->local_consumed += len; | |
1327 | } | |
1328 | } | |
1329 | return 1; | |
1330 | } | |
396c147e | 1331 | static int |
7e7327a1 | 1332 | channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset) |
1333 | { | |
1334 | char buf[16*1024]; | |
1335 | int len; | |
1336 | ||
8ce64345 | 1337 | /** XXX handle drain efd, too */ |
7e7327a1 | 1338 | if (c->efd != -1) { |
1339 | if (c->extended_usage == CHAN_EXTENDED_WRITE && | |
1340 | FD_ISSET(c->efd, writeset) && | |
1341 | buffer_len(&c->extended) > 0) { | |
1342 | len = write(c->efd, buffer_ptr(&c->extended), | |
1343 | buffer_len(&c->extended)); | |
de273eef | 1344 | debug2("channel %d: written %d to efd %d", |
7e7327a1 | 1345 | c->self, len, c->efd); |
ee55dacf | 1346 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1347 | return 1; | |
1348 | if (len <= 0) { | |
1349 | debug2("channel %d: closing write-efd %d", | |
1350 | c->self, c->efd); | |
489aa2e9 | 1351 | channel_close_fd(&c->efd); |
ee55dacf | 1352 | } else { |
7e7327a1 | 1353 | buffer_consume(&c->extended, len); |
1354 | c->local_consumed += len; | |
1355 | } | |
1356 | } else if (c->extended_usage == CHAN_EXTENDED_READ && | |
1357 | FD_ISSET(c->efd, readset)) { | |
1358 | len = read(c->efd, buf, sizeof(buf)); | |
de273eef | 1359 | debug2("channel %d: read %d from efd %d", |
184eed6a | 1360 | c->self, len, c->efd); |
ee55dacf | 1361 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1362 | return 1; | |
1363 | if (len <= 0) { | |
1364 | debug2("channel %d: closing read-efd %d", | |
8ce64345 | 1365 | c->self, c->efd); |
489aa2e9 | 1366 | channel_close_fd(&c->efd); |
ee55dacf | 1367 | } else { |
7e7327a1 | 1368 | buffer_append(&c->extended, buf, len); |
ee55dacf | 1369 | } |
7e7327a1 | 1370 | } |
1371 | } | |
1372 | return 1; | |
1373 | } | |
396c147e | 1374 | static int |
ee55dacf | 1375 | channel_check_window(Channel *c) |
7e7327a1 | 1376 | { |
28b9cb4d | 1377 | if (c->type == SSH_CHANNEL_OPEN && |
1378 | !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) && | |
7e7327a1 | 1379 | c->local_window < c->local_window_max/2 && |
1380 | c->local_consumed > 0) { | |
1381 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); | |
1382 | packet_put_int(c->remote_id); | |
1383 | packet_put_int(c->local_consumed); | |
1384 | packet_send(); | |
de273eef | 1385 | debug2("channel %d: window %d sent adjust %d", |
7e7327a1 | 1386 | c->self, c->local_window, |
1387 | c->local_consumed); | |
1388 | c->local_window += c->local_consumed; | |
1389 | c->local_consumed = 0; | |
7368a6c8 | 1390 | } |
1391 | return 1; | |
1392 | } | |
5260325f | 1393 | |
396c147e | 1394 | static void |
0c0738d5 | 1395 | channel_post_open(Channel *c, fd_set * readset, fd_set * writeset) |
7368a6c8 | 1396 | { |
639cb8ab | 1397 | if (c->delayed) |
1398 | return; | |
7368a6c8 | 1399 | channel_handle_rfd(c, readset, writeset); |
1400 | channel_handle_wfd(c, readset, writeset); | |
0c0738d5 | 1401 | if (!compat20) |
639cb8ab | 1402 | return; |
7e7327a1 | 1403 | channel_handle_efd(c, readset, writeset); |
ee55dacf | 1404 | channel_check_window(c); |
7e7327a1 | 1405 | } |
1406 | ||
396c147e | 1407 | static void |
7368a6c8 | 1408 | channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset) |
1409 | { | |
1410 | int len; | |
e1feb9bf | 1411 | |
7368a6c8 | 1412 | /* Send buffered output data to the socket. */ |
1413 | if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) { | |
1414 | len = write(c->sock, buffer_ptr(&c->output), | |
1415 | buffer_len(&c->output)); | |
1416 | if (len <= 0) | |
9c50edcf | 1417 | buffer_clear(&c->output); |
7368a6c8 | 1418 | else |
1419 | buffer_consume(&c->output, len); | |
1420 | } | |
1421 | } | |
5260325f | 1422 | |
396c147e | 1423 | static void |
7e7327a1 | 1424 | channel_handler_init_20(void) |
1425 | { | |
0c0738d5 | 1426 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open; |
0b242b12 | 1427 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; |
7e7327a1 | 1428 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; |
fa08c86b | 1429 | channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener; |
0b242b12 | 1430 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; |
fa08c86b | 1431 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; |
97fb6912 | 1432 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1433 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7e7327a1 | 1434 | |
0c0738d5 | 1435 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open; |
7e7327a1 | 1436 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; |
fa08c86b | 1437 | channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener; |
0b242b12 | 1438 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; |
fa08c86b | 1439 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; |
97fb6912 | 1440 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
0c0738d5 | 1441 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open; |
7e7327a1 | 1442 | } |
1443 | ||
396c147e | 1444 | static void |
7368a6c8 | 1445 | channel_handler_init_13(void) |
1446 | { | |
1447 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13; | |
1448 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13; | |
1449 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; | |
1450 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; | |
1451 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; | |
1452 | channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining; | |
1453 | channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining; | |
97fb6912 | 1454 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1455 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7368a6c8 | 1456 | |
0c0738d5 | 1457 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open; |
7368a6c8 | 1458 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; |
1459 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
1460 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; | |
1461 | channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13; | |
97fb6912 | 1462 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
0c0738d5 | 1463 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open; |
7368a6c8 | 1464 | } |
5260325f | 1465 | |
396c147e | 1466 | static void |
7368a6c8 | 1467 | channel_handler_init_15(void) |
1468 | { | |
0c0738d5 | 1469 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open; |
0b242b12 | 1470 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; |
7368a6c8 | 1471 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; |
1472 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; | |
1473 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; | |
97fb6912 | 1474 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1475 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7368a6c8 | 1476 | |
1477 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; | |
1478 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
1479 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; | |
0c0738d5 | 1480 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open; |
97fb6912 | 1481 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
0c0738d5 | 1482 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open; |
7368a6c8 | 1483 | } |
1484 | ||
396c147e | 1485 | static void |
7368a6c8 | 1486 | channel_handler_init(void) |
1487 | { | |
1488 | int i; | |
e1feb9bf | 1489 | |
184eed6a | 1490 | for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) { |
7368a6c8 | 1491 | channel_pre[i] = NULL; |
1492 | channel_post[i] = NULL; | |
1493 | } | |
7e7327a1 | 1494 | if (compat20) |
1495 | channel_handler_init_20(); | |
1496 | else if (compat13) | |
7368a6c8 | 1497 | channel_handler_init_13(); |
1498 | else | |
1499 | channel_handler_init_15(); | |
1500 | } | |
1501 | ||
418e724c | 1502 | /* gc dead channels */ |
1503 | static void | |
1504 | channel_garbage_collect(Channel *c) | |
1505 | { | |
1506 | if (c == NULL) | |
1507 | return; | |
1508 | if (c->detach_user != NULL) { | |
1509 | if (!chan_is_dead(c, 0)) | |
1510 | return; | |
1511 | debug("channel %d: gc: notify user", c->self); | |
1512 | c->detach_user(c->self, NULL); | |
1513 | /* if we still have a callback */ | |
1514 | if (c->detach_user != NULL) | |
1515 | return; | |
1516 | debug("channel %d: gc: user detached", c->self); | |
1517 | } | |
1518 | if (!chan_is_dead(c, 1)) | |
1519 | return; | |
1520 | debug("channel %d: garbage collecting", c->self); | |
1521 | channel_free(c); | |
1522 | } | |
1523 | ||
396c147e | 1524 | static void |
7368a6c8 | 1525 | channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset) |
1526 | { | |
1527 | static int did_init = 0; | |
1528 | int i; | |
1529 | Channel *c; | |
1530 | ||
1531 | if (!did_init) { | |
1532 | channel_handler_init(); | |
1533 | did_init = 1; | |
1534 | } | |
1535 | for (i = 0; i < channels_alloc; i++) { | |
719fc62f | 1536 | c = channels[i]; |
1537 | if (c == NULL) | |
5260325f | 1538 | continue; |
6fd8622b | 1539 | if (ftab[c->type] != NULL) |
1540 | (*ftab[c->type])(c, readset, writeset); | |
418e724c | 1541 | channel_garbage_collect(c); |
8efc0c15 | 1542 | } |
8efc0c15 | 1543 | } |
1544 | ||
8e7895b8 | 1545 | /* |
1546 | * Allocate/update select bitmasks and add any bits relevant to channels in | |
1547 | * select bitmasks. | |
1548 | */ | |
6ae2364d | 1549 | void |
c422989b | 1550 | channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp, |
489aa2e9 | 1551 | int *nallocp, int rekeying) |
7368a6c8 | 1552 | { |
39929cdb | 1553 | int n; |
1554 | u_int sz; | |
1555 | ||
1556 | n = MAX(*maxfdp, channel_max_fd); | |
1557 | ||
1558 | sz = howmany(n+1, NFDBITS) * sizeof(fd_mask); | |
489aa2e9 | 1559 | /* perhaps check sz < nalloc/2 and shrink? */ |
1560 | if (*readsetp == NULL || sz > *nallocp) { | |
1561 | *readsetp = xrealloc(*readsetp, sz); | |
1562 | *writesetp = xrealloc(*writesetp, sz); | |
1563 | *nallocp = sz; | |
39929cdb | 1564 | } |
489aa2e9 | 1565 | *maxfdp = n; |
39929cdb | 1566 | memset(*readsetp, 0, sz); |
1567 | memset(*writesetp, 0, sz); | |
1568 | ||
c422989b | 1569 | if (!rekeying) |
1570 | channel_handler(channel_pre, *readsetp, *writesetp); | |
7368a6c8 | 1571 | } |
1572 | ||
8e7895b8 | 1573 | /* |
1574 | * After select, perform any appropriate operations for channels which have | |
1575 | * events pending. | |
1576 | */ | |
6ae2364d | 1577 | void |
7368a6c8 | 1578 | channel_after_select(fd_set * readset, fd_set * writeset) |
1579 | { | |
1580 | channel_handler(channel_post, readset, writeset); | |
1581 | } | |
1582 | ||
8e7895b8 | 1583 | |
39929cdb | 1584 | /* If there is data to send to the connection, enqueue some of it now. */ |
8efc0c15 | 1585 | |
6ae2364d | 1586 | void |
d5bb9418 | 1587 | channel_output_poll(void) |
8efc0c15 | 1588 | { |
7368a6c8 | 1589 | Channel *c; |
f91d9a89 | 1590 | int i; |
1591 | u_int len; | |
5260325f | 1592 | |
1593 | for (i = 0; i < channels_alloc; i++) { | |
719fc62f | 1594 | c = channels[i]; |
1595 | if (c == NULL) | |
1596 | continue; | |
48e671d5 | 1597 | |
8e7895b8 | 1598 | /* |
1599 | * We are only interested in channels that can have buffered | |
1600 | * incoming data. | |
1601 | */ | |
48e671d5 | 1602 | if (compat13) { |
7368a6c8 | 1603 | if (c->type != SSH_CHANNEL_OPEN && |
1604 | c->type != SSH_CHANNEL_INPUT_DRAINING) | |
48e671d5 | 1605 | continue; |
1606 | } else { | |
7368a6c8 | 1607 | if (c->type != SSH_CHANNEL_OPEN) |
48e671d5 | 1608 | continue; |
48e671d5 | 1609 | } |
e78a59f5 | 1610 | if (compat20 && |
1611 | (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) { | |
ee55dacf | 1612 | /* XXX is this true? */ |
418e724c | 1613 | debug3("channel %d: will not send data after close", c->self); |
7e7327a1 | 1614 | continue; |
1615 | } | |
5260325f | 1616 | |
1617 | /* Get the amount of buffered data for this channel. */ | |
ee55dacf | 1618 | if ((c->istate == CHAN_INPUT_OPEN || |
1619 | c->istate == CHAN_INPUT_WAIT_DRAIN) && | |
1620 | (len = buffer_len(&c->input)) > 0) { | |
8e7895b8 | 1621 | /* |
1622 | * Send some data for the other side over the secure | |
1623 | * connection. | |
1624 | */ | |
7e7327a1 | 1625 | if (compat20) { |
1626 | if (len > c->remote_window) | |
1627 | len = c->remote_window; | |
1628 | if (len > c->remote_maxpacket) | |
1629 | len = c->remote_maxpacket; | |
5260325f | 1630 | } else { |
7e7327a1 | 1631 | if (packet_is_interactive()) { |
1632 | if (len > 1024) | |
1633 | len = 512; | |
1634 | } else { | |
1635 | /* Keep the packets at reasonable size. */ | |
1636 | if (len > packet_get_maxsize()/2) | |
1637 | len = packet_get_maxsize()/2; | |
1638 | } | |
5260325f | 1639 | } |
7368a6c8 | 1640 | if (len > 0) { |
7e7327a1 | 1641 | packet_start(compat20 ? |
1642 | SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA); | |
7368a6c8 | 1643 | packet_put_int(c->remote_id); |
1644 | packet_put_string(buffer_ptr(&c->input), len); | |
1645 | packet_send(); | |
1646 | buffer_consume(&c->input, len); | |
1647 | c->remote_window -= len; | |
7368a6c8 | 1648 | } |
1649 | } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) { | |
5260325f | 1650 | if (compat13) |
1651 | fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3"); | |
aa3378df | 1652 | /* |
1653 | * input-buffer is empty and read-socket shutdown: | |
d2296ed7 | 1654 | * tell peer, that we will not send more data: send IEOF. |
1655 | * hack for extended data: delay EOF if EFD still in use. | |
aa3378df | 1656 | */ |
d2296ed7 | 1657 | if (CHANNEL_EFD_INPUT_ACTIVE(c)) |
875ec275 | 1658 | debug2("channel %d: ibuf_empty delayed efd %d/(%d)", |
1659 | c->self, c->efd, buffer_len(&c->extended)); | |
d2296ed7 | 1660 | else |
1661 | chan_ibuf_empty(c); | |
5260325f | 1662 | } |
7e7327a1 | 1663 | /* Send extended data, i.e. stderr */ |
1664 | if (compat20 && | |
d2296ed7 | 1665 | !(c->flags & CHAN_EOF_SENT) && |
7e7327a1 | 1666 | c->remote_window > 0 && |
1667 | (len = buffer_len(&c->extended)) > 0 && | |
1668 | c->extended_usage == CHAN_EXTENDED_READ) { | |
f91d9a89 | 1669 | debug2("channel %d: rwin %u elen %u euse %d", |
ee55dacf | 1670 | c->self, c->remote_window, buffer_len(&c->extended), |
1671 | c->extended_usage); | |
7e7327a1 | 1672 | if (len > c->remote_window) |
1673 | len = c->remote_window; | |
1674 | if (len > c->remote_maxpacket) | |
1675 | len = c->remote_maxpacket; | |
1676 | packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA); | |
1677 | packet_put_int(c->remote_id); | |
1678 | packet_put_int(SSH2_EXTENDED_DATA_STDERR); | |
1679 | packet_put_string(buffer_ptr(&c->extended), len); | |
1680 | packet_send(); | |
1681 | buffer_consume(&c->extended, len); | |
1682 | c->remote_window -= len; | |
ee55dacf | 1683 | debug2("channel %d: sent ext data %d", c->self, len); |
7e7327a1 | 1684 | } |
8efc0c15 | 1685 | } |
8efc0c15 | 1686 | } |
1687 | ||
8e7895b8 | 1688 | |
1689 | /* -- protocol input */ | |
8efc0c15 | 1690 | |
6ae2364d | 1691 | void |
7819b5c3 | 1692 | channel_input_data(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 1693 | { |
48e671d5 | 1694 | int id; |
5260325f | 1695 | char *data; |
1e3b8b07 | 1696 | u_int data_len; |
7368a6c8 | 1697 | Channel *c; |
5260325f | 1698 | |
1699 | /* Get the channel number and verify it. */ | |
48e671d5 | 1700 | id = packet_get_int(); |
7368a6c8 | 1701 | c = channel_lookup(id); |
1702 | if (c == NULL) | |
48e671d5 | 1703 | packet_disconnect("Received data for nonexistent channel %d.", id); |
5260325f | 1704 | |
1705 | /* Ignore any data for non-open channels (might happen on close) */ | |
7368a6c8 | 1706 | if (c->type != SSH_CHANNEL_OPEN && |
1707 | c->type != SSH_CHANNEL_X11_OPEN) | |
48e671d5 | 1708 | return; |
1709 | ||
1710 | /* same for protocol 1.5 if output end is no longer open */ | |
7368a6c8 | 1711 | if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) |
5260325f | 1712 | return; |
1713 | ||
1714 | /* Get the data. */ | |
1715 | data = packet_get_string(&data_len); | |
7368a6c8 | 1716 | |
6aacefa7 | 1717 | if (compat20) { |
7e7327a1 | 1718 | if (data_len > c->local_maxpacket) { |
1719 | log("channel %d: rcvd big packet %d, maxpack %d", | |
1720 | c->self, data_len, c->local_maxpacket); | |
1721 | } | |
1722 | if (data_len > c->local_window) { | |
1723 | log("channel %d: rcvd too much data %d, win %d", | |
1724 | c->self, data_len, c->local_window); | |
1725 | xfree(data); | |
1726 | return; | |
1727 | } | |
1728 | c->local_window -= data_len; | |
7e7327a1 | 1729 | } |
95500969 | 1730 | packet_check_eom(); |
7368a6c8 | 1731 | buffer_append(&c->output, data, data_len); |
5260325f | 1732 | xfree(data); |
8efc0c15 | 1733 | } |
8e7895b8 | 1734 | |
6ae2364d | 1735 | void |
7819b5c3 | 1736 | channel_input_extended_data(int type, u_int32_t seq, void *ctxt) |
7e7327a1 | 1737 | { |
1738 | int id; | |
7e7327a1 | 1739 | char *data; |
a594fa74 | 1740 | u_int data_len, tcode; |
7e7327a1 | 1741 | Channel *c; |
1742 | ||
1743 | /* Get the channel number and verify it. */ | |
1744 | id = packet_get_int(); | |
1745 | c = channel_lookup(id); | |
1746 | ||
1747 | if (c == NULL) | |
1748 | packet_disconnect("Received extended_data for bad channel %d.", id); | |
1749 | if (c->type != SSH_CHANNEL_OPEN) { | |
1750 | log("channel %d: ext data for non open", id); | |
1751 | return; | |
1752 | } | |
d2296ed7 | 1753 | if (c->flags & CHAN_EOF_RCVD) { |
1754 | if (datafellows & SSH_BUG_EXTEOF) | |
1755 | debug("channel %d: accepting ext data after eof", id); | |
1756 | else | |
1757 | packet_disconnect("Received extended_data after EOF " | |
1758 | "on channel %d.", id); | |
1759 | } | |
7e7327a1 | 1760 | tcode = packet_get_int(); |
1761 | if (c->efd == -1 || | |
1762 | c->extended_usage != CHAN_EXTENDED_WRITE || | |
1763 | tcode != SSH2_EXTENDED_DATA_STDERR) { | |
1764 | log("channel %d: bad ext data", c->self); | |
1765 | return; | |
1766 | } | |
1767 | data = packet_get_string(&data_len); | |
95500969 | 1768 | packet_check_eom(); |
7e7327a1 | 1769 | if (data_len > c->local_window) { |
1770 | log("channel %d: rcvd too much extended_data %d, win %d", | |
1771 | c->self, data_len, c->local_window); | |
1772 | xfree(data); | |
1773 | return; | |
1774 | } | |
de273eef | 1775 | debug2("channel %d: rcvd ext data %d", c->self, data_len); |
7e7327a1 | 1776 | c->local_window -= data_len; |
1777 | buffer_append(&c->extended, data, data_len); | |
1778 | xfree(data); | |
1779 | } | |
1780 | ||
6ae2364d | 1781 | void |
7819b5c3 | 1782 | channel_input_ieof(int type, u_int32_t seq, void *ctxt) |
7368a6c8 | 1783 | { |
1784 | int id; | |
1785 | Channel *c; | |
1786 | ||
7368a6c8 | 1787 | id = packet_get_int(); |
95500969 | 1788 | packet_check_eom(); |
7368a6c8 | 1789 | c = channel_lookup(id); |
1790 | if (c == NULL) | |
1791 | packet_disconnect("Received ieof for nonexistent channel %d.", id); | |
1792 | chan_rcvd_ieof(c); | |
a5f82435 | 1793 | |
1794 | /* XXX force input close */ | |
8341f420 | 1795 | if (c->force_drain && c->istate == CHAN_INPUT_OPEN) { |
a5f82435 | 1796 | debug("channel %d: FORCE input drain", c->self); |
1797 | c->istate = CHAN_INPUT_WAIT_DRAIN; | |
32e7d71f | 1798 | if (buffer_len(&c->input) == 0) |
1799 | chan_ibuf_empty(c); | |
a5f82435 | 1800 | } |
1801 | ||
7368a6c8 | 1802 | } |
8efc0c15 | 1803 | |
6ae2364d | 1804 | void |
7819b5c3 | 1805 | channel_input_close(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 1806 | { |
7368a6c8 | 1807 | int id; |
1808 | Channel *c; | |
5260325f | 1809 | |
7368a6c8 | 1810 | id = packet_get_int(); |
95500969 | 1811 | packet_check_eom(); |
7368a6c8 | 1812 | c = channel_lookup(id); |
1813 | if (c == NULL) | |
1814 | packet_disconnect("Received close for nonexistent channel %d.", id); | |
aa3378df | 1815 | |
1816 | /* | |
1817 | * Send a confirmation that we have closed the channel and no more | |
1818 | * data is coming for it. | |
1819 | */ | |
5260325f | 1820 | packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION); |
7368a6c8 | 1821 | packet_put_int(c->remote_id); |
5260325f | 1822 | packet_send(); |
1823 | ||
aa3378df | 1824 | /* |
1825 | * If the channel is in closed state, we have sent a close request, | |
1826 | * and the other side will eventually respond with a confirmation. | |
1827 | * Thus, we cannot free the channel here, because then there would be | |
1828 | * no-one to receive the confirmation. The channel gets freed when | |
1829 | * the confirmation arrives. | |
1830 | */ | |
7368a6c8 | 1831 | if (c->type != SSH_CHANNEL_CLOSED) { |
aa3378df | 1832 | /* |
1833 | * Not a closed channel - mark it as draining, which will | |
1834 | * cause it to be freed later. | |
1835 | */ | |
9c50edcf | 1836 | buffer_clear(&c->input); |
7368a6c8 | 1837 | c->type = SSH_CHANNEL_OUTPUT_DRAINING; |
5260325f | 1838 | } |
8efc0c15 | 1839 | } |
1840 | ||
7368a6c8 | 1841 | /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */ |
6ae2364d | 1842 | void |
7819b5c3 | 1843 | channel_input_oclose(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 1844 | { |
7368a6c8 | 1845 | int id = packet_get_int(); |
1846 | Channel *c = channel_lookup(id); | |
a8a21a53 | 1847 | |
95500969 | 1848 | packet_check_eom(); |
7368a6c8 | 1849 | if (c == NULL) |
1850 | packet_disconnect("Received oclose for nonexistent channel %d.", id); | |
1851 | chan_rcvd_oclose(c); | |
8efc0c15 | 1852 | } |
1853 | ||
6ae2364d | 1854 | void |
7819b5c3 | 1855 | channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt) |
7368a6c8 | 1856 | { |
1857 | int id = packet_get_int(); | |
1858 | Channel *c = channel_lookup(id); | |
1859 | ||
95500969 | 1860 | packet_check_eom(); |
7368a6c8 | 1861 | if (c == NULL) |
1862 | packet_disconnect("Received close confirmation for " | |
1863 | "out-of-range channel %d.", id); | |
1864 | if (c->type != SSH_CHANNEL_CLOSED) | |
1865 | packet_disconnect("Received close confirmation for " | |
1866 | "non-closed channel %d (type %d).", id, c->type); | |
719fc62f | 1867 | channel_free(c); |
7368a6c8 | 1868 | } |
8efc0c15 | 1869 | |
6ae2364d | 1870 | void |
7819b5c3 | 1871 | channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 1872 | { |
7368a6c8 | 1873 | int id, remote_id; |
1874 | Channel *c; | |
5260325f | 1875 | |
7368a6c8 | 1876 | id = packet_get_int(); |
1877 | c = channel_lookup(id); | |
5260325f | 1878 | |
7368a6c8 | 1879 | if (c==NULL || c->type != SSH_CHANNEL_OPENING) |
1880 | packet_disconnect("Received open confirmation for " | |
1881 | "non-opening channel %d.", id); | |
1882 | remote_id = packet_get_int(); | |
aa3378df | 1883 | /* Record the remote channel number and mark that the channel is now open. */ |
7368a6c8 | 1884 | c->remote_id = remote_id; |
1885 | c->type = SSH_CHANNEL_OPEN; | |
7e7327a1 | 1886 | |
1887 | if (compat20) { | |
1888 | c->remote_window = packet_get_int(); | |
1889 | c->remote_maxpacket = packet_get_int(); | |
05ca0898 | 1890 | if (c->confirm) { |
de273eef | 1891 | debug2("callback start"); |
05ca0898 | 1892 | c->confirm(c->self, NULL); |
de273eef | 1893 | debug2("callback done"); |
7e7327a1 | 1894 | } |
f91d9a89 | 1895 | debug("channel %d: open confirm rwindow %u rmax %u", c->self, |
7e7327a1 | 1896 | c->remote_window, c->remote_maxpacket); |
1897 | } | |
95500969 | 1898 | packet_check_eom(); |
8efc0c15 | 1899 | } |
1900 | ||
396c147e | 1901 | static char * |
d18e0850 | 1902 | reason2txt(int reason) |
1903 | { | |
6aacefa7 | 1904 | switch (reason) { |
d18e0850 | 1905 | case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED: |
1906 | return "administratively prohibited"; | |
1907 | case SSH2_OPEN_CONNECT_FAILED: | |
1908 | return "connect failed"; | |
1909 | case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE: | |
1910 | return "unknown channel type"; | |
1911 | case SSH2_OPEN_RESOURCE_SHORTAGE: | |
1912 | return "resource shortage"; | |
1913 | } | |
7e8c18e9 | 1914 | return "unknown reason"; |
d18e0850 | 1915 | } |
1916 | ||
6ae2364d | 1917 | void |
7819b5c3 | 1918 | channel_input_open_failure(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 1919 | { |
02a024dd | 1920 | int id, reason; |
1921 | char *msg = NULL, *lang = NULL; | |
7368a6c8 | 1922 | Channel *c; |
5260325f | 1923 | |
7368a6c8 | 1924 | id = packet_get_int(); |
1925 | c = channel_lookup(id); | |
1926 | ||
1927 | if (c==NULL || c->type != SSH_CHANNEL_OPENING) | |
1928 | packet_disconnect("Received open failure for " | |
1929 | "non-opening channel %d.", id); | |
7e7327a1 | 1930 | if (compat20) { |
02a024dd | 1931 | reason = packet_get_int(); |
fbe90f7b | 1932 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { |
02a024dd | 1933 | msg = packet_get_string(NULL); |
1934 | lang = packet_get_string(NULL); | |
1935 | } | |
d18e0850 | 1936 | log("channel %d: open failed: %s%s%s", id, |
1937 | reason2txt(reason), msg ? ": ": "", msg ? msg : ""); | |
02a024dd | 1938 | if (msg != NULL) |
1939 | xfree(msg); | |
1940 | if (lang != NULL) | |
1941 | xfree(lang); | |
7e7327a1 | 1942 | } |
95500969 | 1943 | packet_check_eom(); |
5260325f | 1944 | /* Free the channel. This will also close the socket. */ |
719fc62f | 1945 | channel_free(c); |
8efc0c15 | 1946 | } |
1947 | ||
8e7895b8 | 1948 | void |
7819b5c3 | 1949 | channel_input_window_adjust(int type, u_int32_t seq, void *ctxt) |
8e7895b8 | 1950 | { |
1951 | Channel *c; | |
f91d9a89 | 1952 | int id; |
1953 | u_int adjust; | |
3ffc6336 | 1954 | |
8e7895b8 | 1955 | if (!compat20) |
1956 | return; | |
8efc0c15 | 1957 | |
8e7895b8 | 1958 | /* Get the channel number and verify it. */ |
1959 | id = packet_get_int(); | |
1960 | c = channel_lookup(id); | |
1961 | ||
1962 | if (c == NULL || c->type != SSH_CHANNEL_OPEN) { | |
1963 | log("Received window adjust for " | |
1964 | "non-open channel %d.", id); | |
1965 | return; | |
1966 | } | |
1967 | adjust = packet_get_int(); | |
95500969 | 1968 | packet_check_eom(); |
f91d9a89 | 1969 | debug2("channel %d: rcvd adjust %u", id, adjust); |
8e7895b8 | 1970 | c->remote_window += adjust; |
1971 | } | |
1972 | ||
1973 | void | |
7819b5c3 | 1974 | channel_input_port_open(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 1975 | { |
8e7895b8 | 1976 | Channel *c = NULL; |
1977 | u_short host_port; | |
1978 | char *host, *originator_string; | |
1979 | int remote_id, sock = -1; | |
5260325f | 1980 | |
8e7895b8 | 1981 | remote_id = packet_get_int(); |
1982 | host = packet_get_string(NULL); | |
1983 | host_port = packet_get_int(); | |
1984 | ||
1985 | if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) { | |
1986 | originator_string = packet_get_string(NULL); | |
1987 | } else { | |
1988 | originator_string = xstrdup("unknown (remote did not supply name)"); | |
1989 | } | |
95500969 | 1990 | packet_check_eom(); |
8e7895b8 | 1991 | sock = channel_connect_to(host, host_port); |
1992 | if (sock != -1) { | |
1993 | c = channel_new("connected socket", | |
1994 | SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0, | |
1995 | originator_string, 1); | |
3a0d3d54 | 1996 | c->remote_id = remote_id; |
5260325f | 1997 | } |
8e7895b8 | 1998 | if (c == NULL) { |
1999 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
2000 | packet_put_int(remote_id); | |
2001 | packet_send(); | |
2002 | } | |
2003 | xfree(host); | |
8efc0c15 | 2004 | } |
2005 | ||
8e7895b8 | 2006 | |
2007 | /* -- tcp forwarding */ | |
2008 | ||
5e4a7219 | 2009 | void |
2010 | channel_set_af(int af) | |
2011 | { | |
2012 | IPv4or6 = af; | |
2013 | } | |
2014 | ||
5641aefa | 2015 | static int |
2016 | channel_setup_fwd_listener(int type, const char *listen_addr, u_short listen_port, | |
2017 | const char *host_to_connect, u_short port_to_connect, int gateway_ports) | |
8efc0c15 | 2018 | { |
719fc62f | 2019 | Channel *c; |
5641aefa | 2020 | int success, sock, on = 1; |
48e671d5 | 2021 | struct addrinfo hints, *ai, *aitop; |
fa08c86b | 2022 | const char *host; |
5641aefa | 2023 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; |
aa3378df | 2024 | struct linger linger; |
5260325f | 2025 | |
02a024dd | 2026 | success = 0; |
5641aefa | 2027 | host = (type == SSH_CHANNEL_RPORT_LISTENER) ? |
2028 | listen_addr : host_to_connect; | |
02a024dd | 2029 | |
5641aefa | 2030 | if (host == NULL) { |
2031 | error("No forward host name."); | |
2032 | return success; | |
fa08c86b | 2033 | } |
719fc62f | 2034 | if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) { |
02a024dd | 2035 | error("Forward host name too long."); |
2036 | return success; | |
2037 | } | |
5260325f | 2038 | |
aa3378df | 2039 | /* |
48e671d5 | 2040 | * getaddrinfo returns a loopback address if the hostname is |
2041 | * set to NULL and hints.ai_flags is not AI_PASSIVE | |
aa3378df | 2042 | */ |
48e671d5 | 2043 | memset(&hints, 0, sizeof(hints)); |
2044 | hints.ai_family = IPv4or6; | |
2045 | hints.ai_flags = gateway_ports ? AI_PASSIVE : 0; | |
2046 | hints.ai_socktype = SOCK_STREAM; | |
fa08c86b | 2047 | snprintf(strport, sizeof strport, "%d", listen_port); |
48e671d5 | 2048 | if (getaddrinfo(NULL, strport, &hints, &aitop) != 0) |
2049 | packet_disconnect("getaddrinfo: fatal error"); | |
2050 | ||
48e671d5 | 2051 | for (ai = aitop; ai; ai = ai->ai_next) { |
2052 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2053 | continue; | |
2054 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), | |
2055 | strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
5641aefa | 2056 | error("channel_setup_fwd_listener: getnameinfo failed"); |
48e671d5 | 2057 | continue; |
2058 | } | |
2059 | /* Create a port to listen for the host. */ | |
2060 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
2061 | if (sock < 0) { | |
2062 | /* this is no error since kernel may not support ipv6 */ | |
2063 | verbose("socket: %.100s", strerror(errno)); | |
2064 | continue; | |
2065 | } | |
2066 | /* | |
2067 | * Set socket options. We would like the socket to disappear | |
2068 | * as soon as it has been closed for whatever reason. | |
2069 | */ | |
db518d9b | 2070 | setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)); |
48e671d5 | 2071 | linger.l_onoff = 1; |
2072 | linger.l_linger = 5; | |
db518d9b | 2073 | setsockopt(sock, SOL_SOCKET, SO_LINGER, &linger, sizeof(linger)); |
48e671d5 | 2074 | debug("Local forwarding listening on %s port %s.", ntop, strport); |
2075 | ||
2076 | /* Bind the socket to the address. */ | |
2077 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
2078 | /* address can be in use ipv6 address is already bound */ | |
16218745 | 2079 | if (!ai->ai_next) |
2080 | error("bind: %.100s", strerror(errno)); | |
2081 | else | |
2082 | verbose("bind: %.100s", strerror(errno)); | |
2b87da3b | 2083 | |
48e671d5 | 2084 | close(sock); |
2085 | continue; | |
2086 | } | |
2087 | /* Start listening for connections on the socket. */ | |
2088 | if (listen(sock, 5) < 0) { | |
2089 | error("listen: %.100s", strerror(errno)); | |
2090 | close(sock); | |
2091 | continue; | |
2092 | } | |
2093 | /* Allocate a channel number for the socket. */ | |
8e7895b8 | 2094 | c = channel_new("port listener", type, sock, sock, -1, |
0b242b12 | 2095 | CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, |
a22aff1f | 2096 | 0, xstrdup("port listener"), 1); |
719fc62f | 2097 | strlcpy(c->path, host, sizeof(c->path)); |
2098 | c->host_port = port_to_connect; | |
2099 | c->listening_port = listen_port; | |
48e671d5 | 2100 | success = 1; |
2101 | } | |
2102 | if (success == 0) | |
5641aefa | 2103 | error("channel_setup_fwd_listener: cannot listen to port: %d", |
02a024dd | 2104 | listen_port); |
48e671d5 | 2105 | freeaddrinfo(aitop); |
02a024dd | 2106 | return success; |
5260325f | 2107 | } |
8efc0c15 | 2108 | |
5641aefa | 2109 | /* protocol local port fwd, used by ssh (and sshd in v1) */ |
2110 | int | |
2111 | channel_setup_local_fwd_listener(u_short listen_port, | |
2112 | const char *host_to_connect, u_short port_to_connect, int gateway_ports) | |
2113 | { | |
2114 | return channel_setup_fwd_listener(SSH_CHANNEL_PORT_LISTENER, | |
2115 | NULL, listen_port, host_to_connect, port_to_connect, gateway_ports); | |
2116 | } | |
2117 | ||
2118 | /* protocol v2 remote port fwd, used by sshd */ | |
2119 | int | |
2120 | channel_setup_remote_fwd_listener(const char *listen_address, | |
2121 | u_short listen_port, int gateway_ports) | |
2122 | { | |
2123 | return channel_setup_fwd_listener(SSH_CHANNEL_RPORT_LISTENER, | |
2124 | listen_address, listen_port, NULL, 0, gateway_ports); | |
2125 | } | |
2126 | ||
aa3378df | 2127 | /* |
2128 | * Initiate forwarding of connections to port "port" on remote host through | |
2129 | * the secure channel to host:port from local side. | |
2130 | */ | |
8efc0c15 | 2131 | |
6ae2364d | 2132 | void |
fa08c86b | 2133 | channel_request_remote_forwarding(u_short listen_port, |
2134 | const char *host_to_connect, u_short port_to_connect) | |
8efc0c15 | 2135 | { |
54a5250f | 2136 | int type, success = 0; |
fa08c86b | 2137 | |
5260325f | 2138 | /* Record locally that connection to this host/port is permitted. */ |
2139 | if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION) | |
2140 | fatal("channel_request_remote_forwarding: too many forwards"); | |
2141 | ||
5260325f | 2142 | /* Send the forward request to the remote side. */ |
7e7327a1 | 2143 | if (compat20) { |
2144 | const char *address_to_bind = "0.0.0.0"; | |
2145 | packet_start(SSH2_MSG_GLOBAL_REQUEST); | |
2146 | packet_put_cstring("tcpip-forward"); | |
e0ae8728 | 2147 | packet_put_char(1); /* boolean: want reply */ |
7e7327a1 | 2148 | packet_put_cstring(address_to_bind); |
2149 | packet_put_int(listen_port); | |
fa08c86b | 2150 | packet_send(); |
2151 | packet_write_wait(); | |
2152 | /* Assume that server accepts the request */ | |
2153 | success = 1; | |
7e7327a1 | 2154 | } else { |
2155 | packet_start(SSH_CMSG_PORT_FORWARD_REQUEST); | |
7e7327a1 | 2156 | packet_put_int(listen_port); |
d6f24e45 | 2157 | packet_put_cstring(host_to_connect); |
2158 | packet_put_int(port_to_connect); | |
7e7327a1 | 2159 | packet_send(); |
2160 | packet_write_wait(); | |
fa08c86b | 2161 | |
2162 | /* Wait for response from the remote side. */ | |
54a5250f | 2163 | type = packet_read(); |
fa08c86b | 2164 | switch (type) { |
2165 | case SSH_SMSG_SUCCESS: | |
2166 | success = 1; | |
2167 | break; | |
2168 | case SSH_SMSG_FAILURE: | |
2169 | log("Warning: Server denied remote port forwarding."); | |
2170 | break; | |
2171 | default: | |
2172 | /* Unknown packet */ | |
2173 | packet_disconnect("Protocol error for port forward request:" | |
2174 | "received packet type %d.", type); | |
2175 | } | |
2176 | } | |
2177 | if (success) { | |
2178 | permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect); | |
2179 | permitted_opens[num_permitted_opens].port_to_connect = port_to_connect; | |
2180 | permitted_opens[num_permitted_opens].listen_port = listen_port; | |
2181 | num_permitted_opens++; | |
7e7327a1 | 2182 | } |
8efc0c15 | 2183 | } |
2184 | ||
aa3378df | 2185 | /* |
2186 | * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates | |
2187 | * listening for the port, and sends back a success reply (or disconnect | |
2188 | * message if there was an error). This never returns if there was an error. | |
2189 | */ | |
8efc0c15 | 2190 | |
6ae2364d | 2191 | void |
1d1ffb87 | 2192 | channel_input_port_forward_request(int is_root, int gateway_ports) |
8efc0c15 | 2193 | { |
57112b5a | 2194 | u_short port, host_port; |
5260325f | 2195 | char *hostname; |
2196 | ||
2197 | /* Get arguments from the packet. */ | |
2198 | port = packet_get_int(); | |
2199 | hostname = packet_get_string(NULL); | |
2200 | host_port = packet_get_int(); | |
2201 | ||
3c62e7eb | 2202 | #ifndef HAVE_CYGWIN |
aa3378df | 2203 | /* |
2204 | * Check that an unprivileged user is not trying to forward a | |
2205 | * privileged port. | |
2206 | */ | |
5260325f | 2207 | if (port < IPPORT_RESERVED && !is_root) |
2208 | packet_disconnect("Requested forwarding of port %d but user is not root.", | |
2209 | port); | |
3c62e7eb | 2210 | #endif |
fa08c86b | 2211 | /* Initiate forwarding */ |
5641aefa | 2212 | channel_setup_local_fwd_listener(port, hostname, host_port, gateway_ports); |
5260325f | 2213 | |
2214 | /* Free the argument string. */ | |
2215 | xfree(hostname); | |
8efc0c15 | 2216 | } |
2217 | ||
01794848 | 2218 | /* |
2219 | * Permits opening to any host/port if permitted_opens[] is empty. This is | |
2220 | * usually called by the server, because the user could connect to any port | |
2221 | * anyway, and the server has no way to know but to trust the client anyway. | |
2222 | */ | |
2223 | void | |
d5bb9418 | 2224 | channel_permit_all_opens(void) |
01794848 | 2225 | { |
2226 | if (num_permitted_opens == 0) | |
2227 | all_opens_permitted = 1; | |
2228 | } | |
2229 | ||
cd332296 | 2230 | void |
01794848 | 2231 | channel_add_permitted_opens(char *host, int port) |
2232 | { | |
2233 | if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION) | |
2234 | fatal("channel_request_remote_forwarding: too many forwards"); | |
2235 | debug("allow port forwarding to host %s port %d", host, port); | |
2236 | ||
2237 | permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host); | |
2238 | permitted_opens[num_permitted_opens].port_to_connect = port; | |
2239 | num_permitted_opens++; | |
2240 | ||
2241 | all_opens_permitted = 0; | |
2242 | } | |
2243 | ||
cd332296 | 2244 | void |
01794848 | 2245 | channel_clear_permitted_opens(void) |
2246 | { | |
2247 | int i; | |
2248 | ||
2249 | for (i = 0; i < num_permitted_opens; i++) | |
2250 | xfree(permitted_opens[i].host_to_connect); | |
2251 | num_permitted_opens = 0; | |
2252 | ||
2253 | } | |
2254 | ||
2255 | ||
2256 | /* return socket to remote host, port */ | |
396c147e | 2257 | static int |
01794848 | 2258 | connect_to(const char *host, u_short port) |
8efc0c15 | 2259 | { |
48e671d5 | 2260 | struct addrinfo hints, *ai, *aitop; |
2261 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; | |
2262 | int gaierr; | |
7368a6c8 | 2263 | int sock = -1; |
48e671d5 | 2264 | |
2265 | memset(&hints, 0, sizeof(hints)); | |
2266 | hints.ai_family = IPv4or6; | |
2267 | hints.ai_socktype = SOCK_STREAM; | |
01794848 | 2268 | snprintf(strport, sizeof strport, "%d", port); |
48e671d5 | 2269 | if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) { |
01794848 | 2270 | error("connect_to %.100s: unknown host (%s)", host, |
2271 | gai_strerror(gaierr)); | |
7368a6c8 | 2272 | return -1; |
48e671d5 | 2273 | } |
48e671d5 | 2274 | for (ai = aitop; ai; ai = ai->ai_next) { |
2275 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2276 | continue; | |
2277 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), | |
2278 | strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
01794848 | 2279 | error("connect_to: getnameinfo failed"); |
48e671d5 | 2280 | continue; |
5260325f | 2281 | } |
48e671d5 | 2282 | sock = socket(ai->ai_family, SOCK_STREAM, 0); |
2283 | if (sock < 0) { | |
2284 | error("socket: %.100s", strerror(errno)); | |
2285 | continue; | |
5260325f | 2286 | } |
eea39c02 | 2287 | if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0) |
97fb6912 | 2288 | fatal("connect_to: F_SETFL: %s", strerror(errno)); |
97fb6912 | 2289 | if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 && |
2290 | errno != EINPROGRESS) { | |
01794848 | 2291 | error("connect_to %.100s port %s: %.100s", ntop, strport, |
48e671d5 | 2292 | strerror(errno)); |
2293 | close(sock); | |
2b87da3b | 2294 | continue; /* fail -- try next */ |
48e671d5 | 2295 | } |
2296 | break; /* success */ | |
5260325f | 2297 | |
5260325f | 2298 | } |
48e671d5 | 2299 | freeaddrinfo(aitop); |
48e671d5 | 2300 | if (!ai) { |
01794848 | 2301 | error("connect_to %.100s port %d: failed.", host, port); |
7368a6c8 | 2302 | return -1; |
8efc0c15 | 2303 | } |
7368a6c8 | 2304 | /* success */ |
811a6342 | 2305 | set_nodelay(sock); |
7368a6c8 | 2306 | return sock; |
2307 | } | |
01794848 | 2308 | |
fa08c86b | 2309 | int |
b3f8a79c | 2310 | channel_connect_by_listen_address(u_short listen_port) |
fa08c86b | 2311 | { |
2312 | int i; | |
01794848 | 2313 | |
fa08c86b | 2314 | for (i = 0; i < num_permitted_opens; i++) |
2315 | if (permitted_opens[i].listen_port == listen_port) | |
01794848 | 2316 | return connect_to( |
fa08c86b | 2317 | permitted_opens[i].host_to_connect, |
2318 | permitted_opens[i].port_to_connect); | |
0b6fbf03 | 2319 | error("WARNING: Server requests forwarding for unknown listen_port %d", |
2320 | listen_port); | |
fa08c86b | 2321 | return -1; |
2322 | } | |
48e671d5 | 2323 | |
01794848 | 2324 | /* Check if connecting to that port is permitted and connect. */ |
2325 | int | |
2326 | channel_connect_to(const char *host, u_short port) | |
2327 | { | |
2328 | int i, permit; | |
2329 | ||
2330 | permit = all_opens_permitted; | |
2331 | if (!permit) { | |
2332 | for (i = 0; i < num_permitted_opens; i++) | |
2333 | if (permitted_opens[i].port_to_connect == port && | |
2334 | strcmp(permitted_opens[i].host_to_connect, host) == 0) | |
2335 | permit = 1; | |
2336 | ||
2337 | } | |
2338 | if (!permit) { | |
2339 | log("Received request to connect to host %.100s port %d, " | |
2340 | "but the request was denied.", host, port); | |
2341 | return -1; | |
2342 | } | |
2343 | return connect_to(host, port); | |
2344 | } | |
2345 | ||
8e7895b8 | 2346 | /* -- X11 forwarding */ |
8efc0c15 | 2347 | |
aa3378df | 2348 | /* |
2349 | * Creates an internet domain socket for listening for X11 connections. | |
57f228e8 | 2350 | * Returns 0 and a suitable display number for the DISPLAY variable |
2351 | * stored in display_numberp , or -1 if an error occurs. | |
aa3378df | 2352 | */ |
c9d0ad9b | 2353 | int |
e6e573bd | 2354 | x11_create_display_inet(int x11_display_offset, int x11_use_localhost, |
57f228e8 | 2355 | int single_connection, u_int *display_numberp) |
8efc0c15 | 2356 | { |
ac151b18 | 2357 | Channel *nc = NULL; |
57112b5a | 2358 | int display_number, sock; |
2359 | u_short port; | |
48e671d5 | 2360 | struct addrinfo hints, *ai, *aitop; |
2361 | char strport[NI_MAXSERV]; | |
2362 | int gaierr, n, num_socks = 0, socks[NUM_SOCKS]; | |
5260325f | 2363 | |
95f1eccc | 2364 | for (display_number = x11_display_offset; |
184eed6a | 2365 | display_number < MAX_DISPLAYS; |
2366 | display_number++) { | |
5260325f | 2367 | port = 6000 + display_number; |
48e671d5 | 2368 | memset(&hints, 0, sizeof(hints)); |
2369 | hints.ai_family = IPv4or6; | |
e6e573bd | 2370 | hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE; |
48e671d5 | 2371 | hints.ai_socktype = SOCK_STREAM; |
2372 | snprintf(strport, sizeof strport, "%d", port); | |
2373 | if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) { | |
2374 | error("getaddrinfo: %.100s", gai_strerror(gaierr)); | |
c9d0ad9b | 2375 | return -1; |
5260325f | 2376 | } |
48e671d5 | 2377 | for (ai = aitop; ai; ai = ai->ai_next) { |
2378 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2379 | continue; | |
2380 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
2381 | if (sock < 0) { | |
4ee81249 | 2382 | if ((errno != EINVAL) && (errno != EAFNOSUPPORT)) { |
80a44451 | 2383 | error("socket: %.100s", strerror(errno)); |
c9d0ad9b | 2384 | return -1; |
80a44451 | 2385 | } else { |
22d89d24 | 2386 | debug("x11_create_display_inet: Socket family %d not supported", |
2387 | ai->ai_family); | |
80a44451 | 2388 | continue; |
2389 | } | |
48e671d5 | 2390 | } |
688aaeda | 2391 | #ifdef IPV6_V6ONLY |
2392 | if (ai->ai_family == AF_INET6) { | |
2393 | int on = 1; | |
2394 | if (setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) < 0) | |
2395 | error("setsockopt IPV6_V6ONLY: %.100s", strerror(errno)); | |
2396 | } | |
2397 | #endif | |
48e671d5 | 2398 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { |
2399 | debug("bind port %d: %.100s", port, strerror(errno)); | |
48e671d5 | 2400 | close(sock); |
16218745 | 2401 | |
2402 | if (ai->ai_next) | |
2403 | continue; | |
2404 | ||
48e671d5 | 2405 | for (n = 0; n < num_socks; n++) { |
48e671d5 | 2406 | close(socks[n]); |
2407 | } | |
2408 | num_socks = 0; | |
2409 | break; | |
2410 | } | |
2411 | socks[num_socks++] = sock; | |
80faa19f | 2412 | #ifndef DONT_TRY_OTHER_AF |
48e671d5 | 2413 | if (num_socks == NUM_SOCKS) |
2414 | break; | |
80faa19f | 2415 | #else |
688aaeda | 2416 | if (x11_use_localhost) { |
2417 | if (num_socks == NUM_SOCKS) | |
2418 | break; | |
2419 | } else { | |
2420 | break; | |
2421 | } | |
80faa19f | 2422 | #endif |
5260325f | 2423 | } |
4ccb01d6 | 2424 | freeaddrinfo(aitop); |
48e671d5 | 2425 | if (num_socks > 0) |
2426 | break; | |
5260325f | 2427 | } |
2428 | if (display_number >= MAX_DISPLAYS) { | |
2429 | error("Failed to allocate internet-domain X11 display socket."); | |
c9d0ad9b | 2430 | return -1; |
8efc0c15 | 2431 | } |
5260325f | 2432 | /* Start listening for connections on the socket. */ |
48e671d5 | 2433 | for (n = 0; n < num_socks; n++) { |
2434 | sock = socks[n]; | |
2435 | if (listen(sock, 5) < 0) { | |
2436 | error("listen: %.100s", strerror(errno)); | |
48e671d5 | 2437 | close(sock); |
c9d0ad9b | 2438 | return -1; |
a7effaac | 2439 | } |
a7effaac | 2440 | } |
5260325f | 2441 | |
48e671d5 | 2442 | /* Allocate a channel for each socket. */ |
2443 | for (n = 0; n < num_socks; n++) { | |
2444 | sock = socks[n]; | |
ac151b18 | 2445 | nc = channel_new("x11 listener", |
0b242b12 | 2446 | SSH_CHANNEL_X11_LISTENER, sock, sock, -1, |
2447 | CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, | |
a22aff1f | 2448 | 0, xstrdup("X11 inet listener"), 1); |
3a0d3d54 | 2449 | nc->single_connection = single_connection; |
48e671d5 | 2450 | } |
5260325f | 2451 | |
c9d0ad9b | 2452 | /* Return the display number for the DISPLAY environment variable. */ |
57f228e8 | 2453 | *display_numberp = display_number; |
2454 | return (0); | |
8efc0c15 | 2455 | } |
2456 | ||
396c147e | 2457 | static int |
1e3b8b07 | 2458 | connect_local_xsocket(u_int dnr) |
8efc0c15 | 2459 | { |
5260325f | 2460 | int sock; |
2461 | struct sockaddr_un addr; | |
5260325f | 2462 | |
805e659f | 2463 | sock = socket(AF_UNIX, SOCK_STREAM, 0); |
2464 | if (sock < 0) | |
2465 | error("socket: %.100s", strerror(errno)); | |
2466 | memset(&addr, 0, sizeof(addr)); | |
2467 | addr.sun_family = AF_UNIX; | |
2468 | snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr); | |
2469 | if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0) | |
2470 | return sock; | |
2471 | close(sock); | |
5260325f | 2472 | error("connect %.100s: %.100s", addr.sun_path, strerror(errno)); |
2473 | return -1; | |
8efc0c15 | 2474 | } |
2475 | ||
0b242b12 | 2476 | int |
2477 | x11_connect_display(void) | |
8efc0c15 | 2478 | { |
bcc0381e | 2479 | int display_number, sock = 0; |
5260325f | 2480 | const char *display; |
0b242b12 | 2481 | char buf[1024], *cp; |
48e671d5 | 2482 | struct addrinfo hints, *ai, *aitop; |
2483 | char strport[NI_MAXSERV]; | |
2484 | int gaierr; | |
5260325f | 2485 | |
5260325f | 2486 | /* Try to open a socket for the local X server. */ |
2487 | display = getenv("DISPLAY"); | |
2488 | if (!display) { | |
2489 | error("DISPLAY not set."); | |
0b242b12 | 2490 | return -1; |
5260325f | 2491 | } |
aa3378df | 2492 | /* |
2493 | * Now we decode the value of the DISPLAY variable and make a | |
2494 | * connection to the real X server. | |
2495 | */ | |
2496 | ||
2497 | /* | |
2498 | * Check if it is a unix domain socket. Unix domain displays are in | |
2499 | * one of the following formats: unix:d[.s], :d[.s], ::d[.s] | |
2500 | */ | |
5260325f | 2501 | if (strncmp(display, "unix:", 5) == 0 || |
2502 | display[0] == ':') { | |
2503 | /* Connect to the unix domain socket. */ | |
2504 | if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) { | |
2505 | error("Could not parse display number from DISPLAY: %.100s", | |
184eed6a | 2506 | display); |
0b242b12 | 2507 | return -1; |
5260325f | 2508 | } |
2509 | /* Create a socket. */ | |
2510 | sock = connect_local_xsocket(display_number); | |
2511 | if (sock < 0) | |
0b242b12 | 2512 | return -1; |
5260325f | 2513 | |
2514 | /* OK, we now have a connection to the display. */ | |
0b242b12 | 2515 | return sock; |
5260325f | 2516 | } |
aa3378df | 2517 | /* |
2518 | * Connect to an inet socket. The DISPLAY value is supposedly | |
2519 | * hostname:d[.s], where hostname may also be numeric IP address. | |
2520 | */ | |
74860245 | 2521 | strlcpy(buf, display, sizeof(buf)); |
5260325f | 2522 | cp = strchr(buf, ':'); |
2523 | if (!cp) { | |
2524 | error("Could not find ':' in DISPLAY: %.100s", display); | |
0b242b12 | 2525 | return -1; |
5260325f | 2526 | } |
2527 | *cp = 0; | |
aa3378df | 2528 | /* buf now contains the host name. But first we parse the display number. */ |
5260325f | 2529 | if (sscanf(cp + 1, "%d", &display_number) != 1) { |
2530 | error("Could not parse display number from DISPLAY: %.100s", | |
184eed6a | 2531 | display); |
0b242b12 | 2532 | return -1; |
5260325f | 2533 | } |
5260325f | 2534 | |
48e671d5 | 2535 | /* Look up the host address */ |
2536 | memset(&hints, 0, sizeof(hints)); | |
2537 | hints.ai_family = IPv4or6; | |
2538 | hints.ai_socktype = SOCK_STREAM; | |
2539 | snprintf(strport, sizeof strport, "%d", 6000 + display_number); | |
2540 | if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) { | |
2541 | error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr)); | |
0b242b12 | 2542 | return -1; |
8efc0c15 | 2543 | } |
48e671d5 | 2544 | for (ai = aitop; ai; ai = ai->ai_next) { |
2545 | /* Create a socket. */ | |
2546 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
2547 | if (sock < 0) { | |
2548 | debug("socket: %.100s", strerror(errno)); | |
7368a6c8 | 2549 | continue; |
2550 | } | |
2551 | /* Connect it to the display. */ | |
2552 | if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
2553 | debug("connect %.100s port %d: %.100s", buf, | |
2554 | 6000 + display_number, strerror(errno)); | |
2555 | close(sock); | |
2556 | continue; | |
2557 | } | |
2558 | /* Success */ | |
2559 | break; | |
48e671d5 | 2560 | } |
48e671d5 | 2561 | freeaddrinfo(aitop); |
2562 | if (!ai) { | |
6ae2364d | 2563 | error("connect %.100s port %d: %.100s", buf, 6000 + display_number, |
48e671d5 | 2564 | strerror(errno)); |
0b242b12 | 2565 | return -1; |
8efc0c15 | 2566 | } |
bcc0381e | 2567 | set_nodelay(sock); |
0b242b12 | 2568 | return sock; |
2569 | } | |
5260325f | 2570 | |
0b242b12 | 2571 | /* |
2572 | * This is called when SSH_SMSG_X11_OPEN is received. The packet contains | |
2573 | * the remote channel number. We should do whatever we want, and respond | |
2574 | * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE. | |
2575 | */ | |
5260325f | 2576 | |
0b242b12 | 2577 | void |
7819b5c3 | 2578 | x11_input_open(int type, u_int32_t seq, void *ctxt) |
0b242b12 | 2579 | { |
719fc62f | 2580 | Channel *c = NULL; |
2581 | int remote_id, sock = 0; | |
0b242b12 | 2582 | char *remote_host; |
5260325f | 2583 | |
719fc62f | 2584 | debug("Received X11 open request."); |
5260325f | 2585 | |
719fc62f | 2586 | remote_id = packet_get_int(); |
8e7895b8 | 2587 | |
2588 | if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) { | |
719fc62f | 2589 | remote_host = packet_get_string(NULL); |
0b242b12 | 2590 | } else { |
2591 | remote_host = xstrdup("unknown (remote did not supply name)"); | |
0b242b12 | 2592 | } |
95500969 | 2593 | packet_check_eom(); |
0b242b12 | 2594 | |
2595 | /* Obtain a connection to the real X display. */ | |
2596 | sock = x11_connect_display(); | |
719fc62f | 2597 | if (sock != -1) { |
2598 | /* Allocate a channel for this connection. */ | |
2599 | c = channel_new("connected x11 socket", | |
2600 | SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0, | |
2601 | remote_host, 1); | |
3a0d3d54 | 2602 | c->remote_id = remote_id; |
2603 | c->force_drain = 1; | |
719fc62f | 2604 | } |
2605 | if (c == NULL) { | |
0b242b12 | 2606 | /* Send refusal to the remote host. */ |
2607 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
719fc62f | 2608 | packet_put_int(remote_id); |
0b242b12 | 2609 | } else { |
0b242b12 | 2610 | /* Send a confirmation to the remote host. */ |
2611 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
719fc62f | 2612 | packet_put_int(remote_id); |
2613 | packet_put_int(c->self); | |
0b242b12 | 2614 | } |
719fc62f | 2615 | packet_send(); |
8efc0c15 | 2616 | } |
2617 | ||
a22aff1f | 2618 | /* dummy protocol handler that denies SSH-1 requests (agent/x11) */ |
2619 | void | |
7819b5c3 | 2620 | deny_input_open(int type, u_int32_t seq, void *ctxt) |
a22aff1f | 2621 | { |
2622 | int rchan = packet_get_int(); | |
e1feb9bf | 2623 | |
6aacefa7 | 2624 | switch (type) { |
a22aff1f | 2625 | case SSH_SMSG_AGENT_OPEN: |
2626 | error("Warning: ssh server tried agent forwarding."); | |
2627 | break; | |
2628 | case SSH_SMSG_X11_OPEN: | |
2629 | error("Warning: ssh server tried X11 forwarding."); | |
2630 | break; | |
2631 | default: | |
7819b5c3 | 2632 | error("deny_input_open: type %d", type); |
a22aff1f | 2633 | break; |
2634 | } | |
2635 | error("Warning: this is probably a break in attempt by a malicious server."); | |
2636 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
2637 | packet_put_int(rchan); | |
2638 | packet_send(); | |
2639 | } | |
2640 | ||
aa3378df | 2641 | /* |
2642 | * Requests forwarding of X11 connections, generates fake authentication | |
2643 | * data, and enables authentication spoofing. | |
8e7895b8 | 2644 | * This should be called in the client only. |
aa3378df | 2645 | */ |
6ae2364d | 2646 | void |
0b242b12 | 2647 | x11_request_forwarding_with_spoofing(int client_session_id, |
2648 | const char *proto, const char *data) | |
8efc0c15 | 2649 | { |
1e3b8b07 | 2650 | u_int data_len = (u_int) strlen(data) / 2; |
ca910e13 | 2651 | u_int i, value, len; |
5260325f | 2652 | char *new_data; |
2653 | int screen_number; | |
2654 | const char *cp; | |
2655 | u_int32_t rand = 0; | |
2656 | ||
2657 | cp = getenv("DISPLAY"); | |
2658 | if (cp) | |
2659 | cp = strchr(cp, ':'); | |
2660 | if (cp) | |
2661 | cp = strchr(cp, '.'); | |
2662 | if (cp) | |
2663 | screen_number = atoi(cp + 1); | |
2664 | else | |
2665 | screen_number = 0; | |
2666 | ||
2667 | /* Save protocol name. */ | |
2668 | x11_saved_proto = xstrdup(proto); | |
2669 | ||
aa3378df | 2670 | /* |
2671 | * Extract real authentication data and generate fake data of the | |
2672 | * same length. | |
2673 | */ | |
5260325f | 2674 | x11_saved_data = xmalloc(data_len); |
2675 | x11_fake_data = xmalloc(data_len); | |
2676 | for (i = 0; i < data_len; i++) { | |
2677 | if (sscanf(data + 2 * i, "%2x", &value) != 1) | |
2678 | fatal("x11_request_forwarding: bad authentication data: %.100s", data); | |
2679 | if (i % 4 == 0) | |
2680 | rand = arc4random(); | |
2681 | x11_saved_data[i] = value; | |
2682 | x11_fake_data[i] = rand & 0xff; | |
2683 | rand >>= 8; | |
2684 | } | |
2685 | x11_saved_data_len = data_len; | |
2686 | x11_fake_data_len = data_len; | |
2687 | ||
2688 | /* Convert the fake data into hex. */ | |
ca910e13 | 2689 | len = 2 * data_len + 1; |
2690 | new_data = xmalloc(len); | |
5260325f | 2691 | for (i = 0; i < data_len; i++) |
ca910e13 | 2692 | snprintf(new_data + 2 * i, len - 2 * i, |
2693 | "%02x", (u_char) x11_fake_data[i]); | |
5260325f | 2694 | |
2695 | /* Send the request packet. */ | |
0b242b12 | 2696 | if (compat20) { |
2697 | channel_request_start(client_session_id, "x11-req", 0); | |
2698 | packet_put_char(0); /* XXX bool single connection */ | |
2699 | } else { | |
2700 | packet_start(SSH_CMSG_X11_REQUEST_FORWARDING); | |
2701 | } | |
2702 | packet_put_cstring(proto); | |
2703 | packet_put_cstring(new_data); | |
5260325f | 2704 | packet_put_int(screen_number); |
2705 | packet_send(); | |
2706 | packet_write_wait(); | |
2707 | xfree(new_data); | |
8efc0c15 | 2708 | } |
2709 | ||
8e7895b8 | 2710 | |
2711 | /* -- agent forwarding */ | |
2712 | ||
8efc0c15 | 2713 | /* Sends a message to the server to request authentication fd forwarding. */ |
2714 | ||
6ae2364d | 2715 | void |
d5bb9418 | 2716 | auth_request_forwarding(void) |
8efc0c15 | 2717 | { |
5260325f | 2718 | packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING); |
2719 | packet_send(); | |
2720 | packet_write_wait(); | |
8efc0c15 | 2721 | } |
2722 | ||
8efc0c15 | 2723 | /* This is called to process an SSH_SMSG_AGENT_OPEN message. */ |
2724 | ||
6ae2364d | 2725 | void |
7819b5c3 | 2726 | auth_input_open_request(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 2727 | { |
719fc62f | 2728 | Channel *c = NULL; |
2729 | int remote_id, sock; | |
8e7895b8 | 2730 | char *name; |
5260325f | 2731 | |
2732 | /* Read the remote channel number from the message. */ | |
719fc62f | 2733 | remote_id = packet_get_int(); |
95500969 | 2734 | packet_check_eom(); |
5260325f | 2735 | |
aa3378df | 2736 | /* |
2737 | * Get a connection to the local authentication agent (this may again | |
2738 | * get forwarded). | |
2739 | */ | |
5260325f | 2740 | sock = ssh_get_authentication_socket(); |
2741 | ||
aa3378df | 2742 | /* |
2743 | * If we could not connect the agent, send an error message back to | |
2744 | * the server. This should never happen unless the agent dies, | |
2745 | * because authentication forwarding is only enabled if we have an | |
2746 | * agent. | |
2747 | */ | |
719fc62f | 2748 | if (sock >= 0) { |
8e7895b8 | 2749 | name = xstrdup("authentication agent connection"); |
2750 | c = channel_new("", SSH_CHANNEL_OPEN, sock, sock, | |
2751 | -1, 0, 0, 0, name, 1); | |
3a0d3d54 | 2752 | c->remote_id = remote_id; |
2753 | c->force_drain = 1; | |
719fc62f | 2754 | } |
2755 | if (c == NULL) { | |
5260325f | 2756 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); |
719fc62f | 2757 | packet_put_int(remote_id); |
2758 | } else { | |
2759 | /* Send a confirmation to the remote host. */ | |
2760 | debug("Forwarding authentication connection."); | |
2761 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
2762 | packet_put_int(remote_id); | |
2763 | packet_put_int(c->self); | |
5260325f | 2764 | } |
5260325f | 2765 | packet_send(); |
8efc0c15 | 2766 | } |