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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. |
a96070d4 | 16 | * Copyright (c) 1999, 2000, 2001 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" | |
780a9951 | 42 | RCSID("$OpenBSD: channels.c,v 1.134 2001/09/17 21:04:01 markus Exp $"); |
8efc0c15 | 43 | |
44 | #include "ssh.h" | |
42f11eb2 | 45 | #include "ssh1.h" |
46 | #include "ssh2.h" | |
8efc0c15 | 47 | #include "packet.h" |
48 | #include "xmalloc.h" | |
8efc0c15 | 49 | #include "uidswap.h" |
42f11eb2 | 50 | #include "log.h" |
51 | #include "misc.h" | |
8efc0c15 | 52 | #include "channels.h" |
8efc0c15 | 53 | #include "compat.h" |
42f11eb2 | 54 | #include "canohost.h" |
4c8722d9 | 55 | #include "key.h" |
56 | #include "authfd.h" | |
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 | ||
131 | /* Name and directory of socket for authentication agent forwarding. */ | |
132 | static char *auth_sock_name = NULL; | |
133 | static char *auth_sock_dir = NULL; | |
134 | ||
8e7895b8 | 135 | /* AF_UNSPEC or AF_INET or AF_INET6 */ |
136 | extern int IPv4or6; | |
137 | ||
138 | /* helper */ | |
396c147e | 139 | static void port_open_helper(Channel *c, char *rtype); |
8e7895b8 | 140 | |
141 | /* -- channel core */ | |
7368a6c8 | 142 | |
143 | Channel * | |
144 | channel_lookup(int id) | |
145 | { | |
146 | Channel *c; | |
719fc62f | 147 | |
3e98362e | 148 | if (id < 0 || id > channels_alloc) { |
7368a6c8 | 149 | log("channel_lookup: %d: bad id", id); |
150 | return NULL; | |
151 | } | |
719fc62f | 152 | c = channels[id]; |
153 | if (c == NULL) { | |
7368a6c8 | 154 | log("channel_lookup: %d: bad id: channel free", id); |
155 | return NULL; | |
156 | } | |
157 | return c; | |
158 | } | |
159 | ||
aa3378df | 160 | /* |
1d1ffb87 | 161 | * Register filedescriptors for a channel, used when allocating a channel or |
0fbe8c74 | 162 | * when the channel consumer/producer is ready, e.g. shell exec'd |
aa3378df | 163 | */ |
8efc0c15 | 164 | |
396c147e | 165 | static void |
a22aff1f | 166 | channel_register_fds(Channel *c, int rfd, int wfd, int efd, |
167 | int extusage, int nonblock) | |
8efc0c15 | 168 | { |
5260325f | 169 | /* Update the maximum file descriptor value. */ |
39929cdb | 170 | channel_max_fd = MAX(channel_max_fd, rfd); |
171 | channel_max_fd = MAX(channel_max_fd, wfd); | |
172 | channel_max_fd = MAX(channel_max_fd, efd); | |
173 | ||
aa3378df | 174 | /* XXX set close-on-exec -markus */ |
1d1ffb87 | 175 | |
0fbe8c74 | 176 | c->rfd = rfd; |
177 | c->wfd = wfd; | |
178 | c->sock = (rfd == wfd) ? rfd : -1; | |
179 | c->efd = efd; | |
180 | c->extended_usage = extusage; | |
a22aff1f | 181 | |
0ae4fe1d | 182 | /* XXX ugly hack: nonblock is only set by the server */ |
183 | if (nonblock && isatty(c->rfd)) { | |
94dfb550 | 184 | debug("channel %d: rfd %d isatty", c->self, c->rfd); |
0ae4fe1d | 185 | c->isatty = 1; |
186 | if (!isatty(c->wfd)) { | |
94dfb550 | 187 | error("channel %d: wfd %d is not a tty?", |
0ae4fe1d | 188 | c->self, c->wfd); |
189 | } | |
190 | } else { | |
191 | c->isatty = 0; | |
192 | } | |
193 | ||
a22aff1f | 194 | /* enable nonblocking mode */ |
195 | if (nonblock) { | |
196 | if (rfd != -1) | |
197 | set_nonblock(rfd); | |
198 | if (wfd != -1) | |
199 | set_nonblock(wfd); | |
200 | if (efd != -1) | |
201 | set_nonblock(efd); | |
202 | } | |
0fbe8c74 | 203 | } |
204 | ||
205 | /* | |
206 | * Allocate a new channel object and set its type and socket. This will cause | |
207 | * remote_name to be freed. | |
208 | */ | |
209 | ||
719fc62f | 210 | Channel * |
0fbe8c74 | 211 | channel_new(char *ctype, int type, int rfd, int wfd, int efd, |
a22aff1f | 212 | int window, int maxpack, int extusage, char *remote_name, int nonblock) |
0fbe8c74 | 213 | { |
214 | int i, found; | |
215 | Channel *c; | |
5260325f | 216 | |
217 | /* Do initial allocation if this is the first call. */ | |
218 | if (channels_alloc == 0) { | |
7e7327a1 | 219 | chan_init(); |
5260325f | 220 | channels_alloc = 10; |
719fc62f | 221 | channels = xmalloc(channels_alloc * sizeof(Channel *)); |
5260325f | 222 | for (i = 0; i < channels_alloc; i++) |
719fc62f | 223 | channels[i] = NULL; |
d6746a0b | 224 | fatal_add_cleanup((void (*) (void *)) channel_free_all, NULL); |
5260325f | 225 | } |
226 | /* Try to find a free slot where to put the new channel. */ | |
227 | for (found = -1, i = 0; i < channels_alloc; i++) | |
719fc62f | 228 | if (channels[i] == NULL) { |
5260325f | 229 | /* Found a free slot. */ |
230 | found = i; | |
231 | break; | |
232 | } | |
233 | if (found == -1) { | |
aa3378df | 234 | /* There are no free slots. Take last+1 slot and expand the array. */ |
5260325f | 235 | found = channels_alloc; |
236 | channels_alloc += 10; | |
de273eef | 237 | debug2("channel: expanding %d", channels_alloc); |
719fc62f | 238 | channels = xrealloc(channels, channels_alloc * sizeof(Channel *)); |
5260325f | 239 | for (i = found; i < channels_alloc; i++) |
719fc62f | 240 | channels[i] = NULL; |
5260325f | 241 | } |
719fc62f | 242 | /* Initialize and return new channel. */ |
243 | c = channels[found] = xmalloc(sizeof(Channel)); | |
5260325f | 244 | buffer_init(&c->input); |
245 | buffer_init(&c->output); | |
7368a6c8 | 246 | buffer_init(&c->extended); |
5260325f | 247 | chan_init_iostates(c); |
a22aff1f | 248 | channel_register_fds(c, rfd, wfd, efd, extusage, nonblock); |
5260325f | 249 | c->self = found; |
250 | c->type = type; | |
7368a6c8 | 251 | c->ctype = ctype; |
0b242b12 | 252 | c->local_window = window; |
253 | c->local_window_max = window; | |
254 | c->local_consumed = 0; | |
255 | c->local_maxpacket = maxpack; | |
5260325f | 256 | c->remote_id = -1; |
257 | c->remote_name = remote_name; | |
7368a6c8 | 258 | c->remote_window = 0; |
259 | c->remote_maxpacket = 0; | |
260 | c->cb_fn = NULL; | |
261 | c->cb_arg = NULL; | |
262 | c->cb_event = 0; | |
a5f82435 | 263 | c->force_drain = 0; |
3cf2be58 | 264 | c->detach_user = 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 | ||
3cf2be58 | 333 | if (c->detach_user != NULL) { |
334 | debug("channel_free: channel %d: detaching channel user", c->self); | |
335 | c->detach_user(c->self, NULL); | |
8e7895b8 | 336 | } |
337 | if (c->sock != -1) | |
338 | shutdown(c->sock, SHUT_RDWR); | |
339 | channel_close_fds(c); | |
340 | buffer_free(&c->input); | |
341 | buffer_free(&c->output); | |
342 | buffer_free(&c->extended); | |
343 | if (c->remote_name) { | |
344 | xfree(c->remote_name); | |
345 | c->remote_name = NULL; | |
346 | } | |
347 | channels[c->self] = NULL; | |
348 | xfree(c); | |
349 | } | |
350 | ||
8e7895b8 | 351 | void |
d6746a0b | 352 | channel_free_all(void) |
8e7895b8 | 353 | { |
354 | int i; | |
8e7895b8 | 355 | |
d6746a0b | 356 | for (i = 0; i < channels_alloc; i++) |
357 | if (channels[i] != NULL) | |
358 | channel_free(channels[i]); | |
8e7895b8 | 359 | } |
360 | ||
3cf2be58 | 361 | void |
362 | channel_detach_all(void) | |
363 | { | |
364 | int i; | |
365 | Channel *c; | |
366 | ||
367 | for (i = 0; i < channels_alloc; i++) { | |
368 | c = channels[i]; | |
369 | if (c != NULL && c->detach_user != NULL) { | |
370 | debug("channel_detach_all: channel %d", c->self); | |
371 | c->detach_user(c->self, NULL); | |
372 | c->detach_user = NULL; | |
373 | } | |
374 | } | |
375 | } | |
376 | ||
8e7895b8 | 377 | /* |
378 | * Closes the sockets/fds of all channels. This is used to close extra file | |
379 | * descriptors after a fork. | |
380 | */ | |
381 | ||
382 | void | |
383 | channel_close_all() | |
384 | { | |
385 | int i; | |
386 | ||
387 | for (i = 0; i < channels_alloc; i++) | |
388 | if (channels[i] != NULL) | |
389 | channel_close_fds(channels[i]); | |
390 | } | |
391 | ||
3cf2be58 | 392 | /* |
393 | * Stop listening to channels. | |
394 | */ | |
395 | ||
396 | void | |
397 | channel_stop_listening(void) | |
398 | { | |
399 | int i; | |
400 | Channel *c; | |
401 | ||
402 | for (i = 0; i < channels_alloc; i++) { | |
403 | c = channels[i]; | |
404 | if (c != NULL) { | |
405 | switch (c->type) { | |
406 | case SSH_CHANNEL_AUTH_SOCKET: | |
407 | case SSH_CHANNEL_PORT_LISTENER: | |
408 | case SSH_CHANNEL_RPORT_LISTENER: | |
409 | case SSH_CHANNEL_X11_LISTENER: | |
489aa2e9 | 410 | channel_close_fd(&c->sock); |
3cf2be58 | 411 | channel_free(c); |
412 | break; | |
413 | } | |
414 | } | |
415 | } | |
416 | } | |
417 | ||
8e7895b8 | 418 | /* |
419 | * Returns true if no channel has too much buffered data, and false if one or | |
420 | * more channel is overfull. | |
421 | */ | |
422 | ||
423 | int | |
424 | channel_not_very_much_buffered_data() | |
425 | { | |
426 | u_int i; | |
427 | Channel *c; | |
428 | ||
429 | for (i = 0; i < channels_alloc; i++) { | |
430 | c = channels[i]; | |
431 | if (c != NULL && c->type == SSH_CHANNEL_OPEN) { | |
432 | if (!compat20 && buffer_len(&c->input) > packet_get_maxsize()) { | |
433 | debug("channel %d: big input buffer %d", | |
434 | c->self, buffer_len(&c->input)); | |
435 | return 0; | |
436 | } | |
437 | if (buffer_len(&c->output) > packet_get_maxsize()) { | |
438 | debug("channel %d: big output buffer %d", | |
439 | c->self, buffer_len(&c->output)); | |
440 | return 0; | |
441 | } | |
442 | } | |
443 | } | |
444 | return 1; | |
445 | } | |
446 | ||
447 | /* Returns true if any channel is still open. */ | |
448 | ||
449 | int | |
450 | channel_still_open() | |
451 | { | |
452 | int i; | |
453 | Channel *c; | |
454 | ||
455 | for (i = 0; i < channels_alloc; i++) { | |
456 | c = channels[i]; | |
457 | if (c == NULL) | |
458 | continue; | |
459 | switch (c->type) { | |
460 | case SSH_CHANNEL_X11_LISTENER: | |
461 | case SSH_CHANNEL_PORT_LISTENER: | |
462 | case SSH_CHANNEL_RPORT_LISTENER: | |
463 | case SSH_CHANNEL_CLOSED: | |
464 | case SSH_CHANNEL_AUTH_SOCKET: | |
465 | case SSH_CHANNEL_DYNAMIC: | |
466 | case SSH_CHANNEL_CONNECTING: | |
467 | case SSH_CHANNEL_ZOMBIE: | |
468 | continue; | |
469 | case SSH_CHANNEL_LARVAL: | |
470 | if (!compat20) | |
471 | fatal("cannot happen: SSH_CHANNEL_LARVAL"); | |
472 | continue; | |
473 | case SSH_CHANNEL_OPENING: | |
474 | case SSH_CHANNEL_OPEN: | |
475 | case SSH_CHANNEL_X11_OPEN: | |
476 | return 1; | |
477 | case SSH_CHANNEL_INPUT_DRAINING: | |
478 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
479 | if (!compat13) | |
480 | fatal("cannot happen: OUT_DRAIN"); | |
481 | return 1; | |
482 | default: | |
483 | fatal("channel_still_open: bad channel type %d", c->type); | |
484 | /* NOTREACHED */ | |
485 | } | |
486 | } | |
487 | return 0; | |
488 | } | |
489 | ||
490 | /* Returns the id of an open channel suitable for keepaliving */ | |
491 | ||
492 | int | |
493 | channel_find_open() | |
494 | { | |
495 | int i; | |
496 | Channel *c; | |
497 | ||
498 | for (i = 0; i < channels_alloc; i++) { | |
499 | c = channels[i]; | |
500 | if (c == NULL) | |
501 | continue; | |
502 | switch (c->type) { | |
503 | case SSH_CHANNEL_CLOSED: | |
504 | case SSH_CHANNEL_DYNAMIC: | |
505 | case SSH_CHANNEL_X11_LISTENER: | |
506 | case SSH_CHANNEL_PORT_LISTENER: | |
507 | case SSH_CHANNEL_RPORT_LISTENER: | |
508 | case SSH_CHANNEL_OPENING: | |
509 | case SSH_CHANNEL_CONNECTING: | |
510 | case SSH_CHANNEL_ZOMBIE: | |
511 | continue; | |
512 | case SSH_CHANNEL_LARVAL: | |
513 | case SSH_CHANNEL_AUTH_SOCKET: | |
514 | case SSH_CHANNEL_OPEN: | |
515 | case SSH_CHANNEL_X11_OPEN: | |
516 | return i; | |
517 | case SSH_CHANNEL_INPUT_DRAINING: | |
518 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
519 | if (!compat13) | |
520 | fatal("cannot happen: OUT_DRAIN"); | |
521 | return i; | |
522 | default: | |
523 | fatal("channel_find_open: bad channel type %d", c->type); | |
524 | /* NOTREACHED */ | |
525 | } | |
526 | } | |
527 | return -1; | |
528 | } | |
529 | ||
530 | ||
531 | /* | |
532 | * Returns a message describing the currently open forwarded connections, | |
533 | * suitable for sending to the client. The message contains crlf pairs for | |
534 | * newlines. | |
535 | */ | |
536 | ||
537 | char * | |
538 | channel_open_message() | |
539 | { | |
540 | Buffer buffer; | |
541 | Channel *c; | |
542 | char buf[1024], *cp; | |
543 | int i; | |
544 | ||
545 | buffer_init(&buffer); | |
546 | snprintf(buf, sizeof buf, "The following connections are open:\r\n"); | |
547 | buffer_append(&buffer, buf, strlen(buf)); | |
548 | for (i = 0; i < channels_alloc; i++) { | |
549 | c = channels[i]; | |
550 | if (c == NULL) | |
551 | continue; | |
552 | switch (c->type) { | |
553 | case SSH_CHANNEL_X11_LISTENER: | |
554 | case SSH_CHANNEL_PORT_LISTENER: | |
555 | case SSH_CHANNEL_RPORT_LISTENER: | |
556 | case SSH_CHANNEL_CLOSED: | |
557 | case SSH_CHANNEL_AUTH_SOCKET: | |
558 | case SSH_CHANNEL_ZOMBIE: | |
559 | continue; | |
560 | case SSH_CHANNEL_LARVAL: | |
561 | case SSH_CHANNEL_OPENING: | |
562 | case SSH_CHANNEL_CONNECTING: | |
563 | case SSH_CHANNEL_DYNAMIC: | |
564 | case SSH_CHANNEL_OPEN: | |
565 | case SSH_CHANNEL_X11_OPEN: | |
566 | case SSH_CHANNEL_INPUT_DRAINING: | |
567 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
568 | snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n", | |
569 | c->self, c->remote_name, | |
570 | c->type, c->remote_id, | |
571 | c->istate, buffer_len(&c->input), | |
572 | c->ostate, buffer_len(&c->output), | |
573 | c->rfd, c->wfd); | |
574 | buffer_append(&buffer, buf, strlen(buf)); | |
575 | continue; | |
576 | default: | |
577 | fatal("channel_open_message: bad channel type %d", c->type); | |
578 | /* NOTREACHED */ | |
579 | } | |
580 | } | |
581 | buffer_append(&buffer, "\0", 1); | |
582 | cp = xstrdup(buffer_ptr(&buffer)); | |
583 | buffer_free(&buffer); | |
584 | return cp; | |
585 | } | |
586 | ||
587 | void | |
588 | channel_send_open(int id) | |
589 | { | |
590 | Channel *c = channel_lookup(id); | |
591 | if (c == NULL) { | |
592 | log("channel_send_open: %d: bad id", id); | |
593 | return; | |
594 | } | |
595 | debug("send channel open %d", id); | |
596 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
597 | packet_put_cstring(c->ctype); | |
598 | packet_put_int(c->self); | |
599 | packet_put_int(c->local_window); | |
600 | packet_put_int(c->local_maxpacket); | |
601 | packet_send(); | |
602 | } | |
603 | ||
604 | void | |
605 | channel_request(int id, char *service, int wantconfirm) | |
606 | { | |
607 | channel_request_start(id, service, wantconfirm); | |
608 | packet_send(); | |
609 | debug("channel request %d: %s", id, service) ; | |
610 | } | |
611 | void | |
612 | channel_request_start(int id, char *service, int wantconfirm) | |
613 | { | |
614 | Channel *c = channel_lookup(id); | |
615 | if (c == NULL) { | |
616 | log("channel_request: %d: bad id", id); | |
617 | return; | |
618 | } | |
619 | packet_start(SSH2_MSG_CHANNEL_REQUEST); | |
620 | packet_put_int(c->remote_id); | |
621 | packet_put_cstring(service); | |
622 | packet_put_char(wantconfirm); | |
623 | } | |
624 | void | |
625 | channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg) | |
626 | { | |
627 | Channel *c = channel_lookup(id); | |
628 | if (c == NULL) { | |
629 | log("channel_register_callback: %d: bad id", id); | |
630 | return; | |
631 | } | |
632 | c->cb_event = mtype; | |
633 | c->cb_fn = fn; | |
634 | c->cb_arg = arg; | |
635 | } | |
636 | void | |
637 | channel_register_cleanup(int id, channel_callback_fn *fn) | |
638 | { | |
639 | Channel *c = channel_lookup(id); | |
640 | if (c == NULL) { | |
641 | log("channel_register_cleanup: %d: bad id", id); | |
642 | return; | |
643 | } | |
3cf2be58 | 644 | c->detach_user = fn; |
8e7895b8 | 645 | } |
646 | void | |
647 | channel_cancel_cleanup(int id) | |
648 | { | |
649 | Channel *c = channel_lookup(id); | |
650 | if (c == NULL) { | |
651 | log("channel_cancel_cleanup: %d: bad id", id); | |
652 | return; | |
653 | } | |
3cf2be58 | 654 | c->detach_user = NULL; |
8e7895b8 | 655 | } |
656 | void | |
657 | channel_register_filter(int id, channel_filter_fn *fn) | |
658 | { | |
659 | Channel *c = channel_lookup(id); | |
660 | if (c == NULL) { | |
661 | log("channel_register_filter: %d: bad id", id); | |
662 | return; | |
663 | } | |
664 | c->input_filter = fn; | |
665 | } | |
666 | ||
6ae2364d | 667 | void |
8e7895b8 | 668 | channel_set_fds(int id, int rfd, int wfd, int efd, |
669 | int extusage, int nonblock) | |
8efc0c15 | 670 | { |
8e7895b8 | 671 | Channel *c = channel_lookup(id); |
672 | if (c == NULL || c->type != SSH_CHANNEL_LARVAL) | |
673 | fatal("channel_activate for non-larval channel %d.", id); | |
674 | channel_register_fds(c, rfd, wfd, efd, extusage, nonblock); | |
675 | c->type = SSH_CHANNEL_OPEN; | |
676 | /* XXX window size? */ | |
677 | c->local_window = c->local_window_max = c->local_maxpacket * 2; | |
678 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); | |
679 | packet_put_int(c->remote_id); | |
680 | packet_put_int(c->local_window); | |
681 | packet_send(); | |
8efc0c15 | 682 | } |
683 | ||
aa3378df | 684 | /* |
7368a6c8 | 685 | * 'channel_pre*' are called just before select() to add any bits relevant to |
686 | * channels in the select bitmasks. | |
aa3378df | 687 | */ |
7368a6c8 | 688 | /* |
689 | * 'channel_post*': perform any appropriate operations for channels which | |
690 | * have events pending. | |
691 | */ | |
692 | typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset); | |
693 | chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE]; | |
694 | chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE]; | |
8efc0c15 | 695 | |
396c147e | 696 | static void |
7368a6c8 | 697 | channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset) |
8efc0c15 | 698 | { |
7368a6c8 | 699 | FD_SET(c->sock, readset); |
700 | } | |
5260325f | 701 | |
396c147e | 702 | static void |
97fb6912 | 703 | channel_pre_connecting(Channel *c, fd_set * readset, fd_set * writeset) |
704 | { | |
705 | debug3("channel %d: waiting for connection", c->self); | |
706 | FD_SET(c->sock, writeset); | |
707 | } | |
708 | ||
396c147e | 709 | static void |
7368a6c8 | 710 | channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset) |
711 | { | |
712 | if (buffer_len(&c->input) < packet_get_maxsize()) | |
713 | FD_SET(c->sock, readset); | |
714 | if (buffer_len(&c->output) > 0) | |
715 | FD_SET(c->sock, writeset); | |
716 | } | |
5260325f | 717 | |
396c147e | 718 | static void |
7368a6c8 | 719 | channel_pre_open_15(Channel *c, fd_set * readset, fd_set * writeset) |
720 | { | |
721 | /* test whether sockets are 'alive' for read/write */ | |
722 | if (c->istate == CHAN_INPUT_OPEN) | |
723 | if (buffer_len(&c->input) < packet_get_maxsize()) | |
724 | FD_SET(c->sock, readset); | |
725 | if (c->ostate == CHAN_OUTPUT_OPEN || | |
726 | c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
727 | if (buffer_len(&c->output) > 0) { | |
728 | FD_SET(c->sock, writeset); | |
729 | } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
730 | chan_obuf_empty(c); | |
731 | } | |
732 | } | |
733 | } | |
5260325f | 734 | |
396c147e | 735 | static void |
7e7327a1 | 736 | channel_pre_open_20(Channel *c, fd_set * readset, fd_set * writeset) |
737 | { | |
738 | if (c->istate == CHAN_INPUT_OPEN && | |
739 | c->remote_window > 0 && | |
740 | buffer_len(&c->input) < c->remote_window) | |
741 | FD_SET(c->rfd, readset); | |
742 | if (c->ostate == CHAN_OUTPUT_OPEN || | |
743 | c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
744 | if (buffer_len(&c->output) > 0) { | |
745 | FD_SET(c->wfd, writeset); | |
746 | } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
747 | chan_obuf_empty(c); | |
748 | } | |
749 | } | |
750 | /** XXX check close conditions, too */ | |
751 | if (c->efd != -1) { | |
752 | if (c->extended_usage == CHAN_EXTENDED_WRITE && | |
753 | buffer_len(&c->extended) > 0) | |
754 | FD_SET(c->efd, writeset); | |
755 | else if (c->extended_usage == CHAN_EXTENDED_READ && | |
756 | buffer_len(&c->extended) < c->remote_window) | |
757 | FD_SET(c->efd, readset); | |
758 | } | |
759 | } | |
760 | ||
396c147e | 761 | static void |
7368a6c8 | 762 | channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset) |
763 | { | |
764 | if (buffer_len(&c->input) == 0) { | |
765 | packet_start(SSH_MSG_CHANNEL_CLOSE); | |
766 | packet_put_int(c->remote_id); | |
767 | packet_send(); | |
768 | c->type = SSH_CHANNEL_CLOSED; | |
070adba2 | 769 | debug("channel %d: closing after input drain.", c->self); |
7368a6c8 | 770 | } |
771 | } | |
5260325f | 772 | |
396c147e | 773 | static void |
7368a6c8 | 774 | channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset) |
775 | { | |
776 | if (buffer_len(&c->output) == 0) | |
719fc62f | 777 | chan_mark_dead(c); |
6ae2364d | 778 | else |
7368a6c8 | 779 | FD_SET(c->sock, writeset); |
780 | } | |
5260325f | 781 | |
7368a6c8 | 782 | /* |
783 | * This is a special state for X11 authentication spoofing. An opened X11 | |
784 | * connection (when authentication spoofing is being done) remains in this | |
785 | * state until the first packet has been completely read. The authentication | |
786 | * data in that packet is then substituted by the real data if it matches the | |
787 | * fake data, and the channel is put into normal mode. | |
0b242b12 | 788 | * XXX All this happens at the client side. |
8e7895b8 | 789 | * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok |
7368a6c8 | 790 | */ |
396c147e | 791 | static int |
8e7895b8 | 792 | x11_open_helper(Buffer *b) |
7368a6c8 | 793 | { |
1e3b8b07 | 794 | u_char *ucp; |
795 | u_int proto_len, data_len; | |
5260325f | 796 | |
7368a6c8 | 797 | /* Check if the fixed size part of the packet is in buffer. */ |
8e7895b8 | 798 | if (buffer_len(b) < 12) |
7368a6c8 | 799 | return 0; |
800 | ||
801 | /* Parse the lengths of variable-length fields. */ | |
8e7895b8 | 802 | ucp = (u_char *) buffer_ptr(b); |
7368a6c8 | 803 | if (ucp[0] == 0x42) { /* Byte order MSB first. */ |
804 | proto_len = 256 * ucp[6] + ucp[7]; | |
805 | data_len = 256 * ucp[8] + ucp[9]; | |
806 | } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */ | |
807 | proto_len = ucp[6] + 256 * ucp[7]; | |
808 | data_len = ucp[8] + 256 * ucp[9]; | |
809 | } else { | |
810 | debug("Initial X11 packet contains bad byte order byte: 0x%x", | |
811 | ucp[0]); | |
812 | return -1; | |
813 | } | |
5260325f | 814 | |
7368a6c8 | 815 | /* Check if the whole packet is in buffer. */ |
8e7895b8 | 816 | if (buffer_len(b) < |
7368a6c8 | 817 | 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3)) |
818 | return 0; | |
5260325f | 819 | |
7368a6c8 | 820 | /* Check if authentication protocol matches. */ |
821 | if (proto_len != strlen(x11_saved_proto) || | |
822 | memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) { | |
823 | debug("X11 connection uses different authentication protocol."); | |
824 | return -1; | |
825 | } | |
826 | /* Check if authentication data matches our fake data. */ | |
827 | if (data_len != x11_fake_data_len || | |
828 | memcmp(ucp + 12 + ((proto_len + 3) & ~3), | |
829 | x11_fake_data, x11_fake_data_len) != 0) { | |
830 | debug("X11 auth data does not match fake data."); | |
831 | return -1; | |
832 | } | |
833 | /* Check fake data length */ | |
834 | if (x11_fake_data_len != x11_saved_data_len) { | |
835 | error("X11 fake_data_len %d != saved_data_len %d", | |
836 | x11_fake_data_len, x11_saved_data_len); | |
837 | return -1; | |
838 | } | |
839 | /* | |
840 | * Received authentication protocol and data match | |
841 | * our fake data. Substitute the fake data with real | |
842 | * data. | |
843 | */ | |
844 | memcpy(ucp + 12 + ((proto_len + 3) & ~3), | |
845 | x11_saved_data, x11_saved_data_len); | |
846 | return 1; | |
847 | } | |
5260325f | 848 | |
396c147e | 849 | static void |
7368a6c8 | 850 | channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset) |
851 | { | |
8e7895b8 | 852 | int ret = x11_open_helper(&c->output); |
7368a6c8 | 853 | if (ret == 1) { |
854 | /* Start normal processing for the channel. */ | |
855 | c->type = SSH_CHANNEL_OPEN; | |
a8be9f80 | 856 | channel_pre_open_13(c, readset, writeset); |
7368a6c8 | 857 | } else if (ret == -1) { |
858 | /* | |
859 | * We have received an X11 connection that has bad | |
860 | * authentication information. | |
861 | */ | |
54b974dc | 862 | log("X11 connection rejected because of wrong authentication."); |
7368a6c8 | 863 | buffer_clear(&c->input); |
864 | buffer_clear(&c->output); | |
489aa2e9 | 865 | channel_close_fd(&c->sock); |
7368a6c8 | 866 | c->sock = -1; |
867 | c->type = SSH_CHANNEL_CLOSED; | |
868 | packet_start(SSH_MSG_CHANNEL_CLOSE); | |
869 | packet_put_int(c->remote_id); | |
870 | packet_send(); | |
871 | } | |
872 | } | |
5260325f | 873 | |
396c147e | 874 | static void |
0b242b12 | 875 | channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset) |
7368a6c8 | 876 | { |
8e7895b8 | 877 | int ret = x11_open_helper(&c->output); |
a5f82435 | 878 | |
879 | /* c->force_drain = 1; */ | |
880 | ||
7368a6c8 | 881 | if (ret == 1) { |
882 | c->type = SSH_CHANNEL_OPEN; | |
d0c832f3 | 883 | if (compat20) |
884 | channel_pre_open_20(c, readset, writeset); | |
885 | else | |
886 | channel_pre_open_15(c, readset, writeset); | |
7368a6c8 | 887 | } else if (ret == -1) { |
888 | debug("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate); | |
0b242b12 | 889 | chan_read_failed(c); /** force close? */ |
7368a6c8 | 890 | chan_write_failed(c); |
891 | debug("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate); | |
892 | } | |
893 | } | |
5260325f | 894 | |
28b9cb4d | 895 | /* try to decode a socks4 header */ |
396c147e | 896 | static int |
28b9cb4d | 897 | channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset) |
0490e609 | 898 | { |
899 | u_char *p, *host; | |
53b8fe68 | 900 | int len, have, i, found; |
28b9cb4d | 901 | char username[256]; |
0490e609 | 902 | struct { |
903 | u_int8_t version; | |
904 | u_int8_t command; | |
905 | u_int16_t dest_port; | |
28b9cb4d | 906 | struct in_addr dest_addr; |
0490e609 | 907 | } s4_req, s4_rsp; |
908 | ||
28b9cb4d | 909 | debug2("channel %d: decode socks4", c->self); |
53b8fe68 | 910 | |
911 | have = buffer_len(&c->input); | |
912 | len = sizeof(s4_req); | |
913 | if (have < len) | |
914 | return 0; | |
915 | p = buffer_ptr(&c->input); | |
916 | for (found = 0, i = len; i < have; i++) { | |
917 | if (p[i] == '\0') { | |
918 | found = 1; | |
919 | break; | |
920 | } | |
921 | if (i > 1024) { | |
922 | /* the peer is probably sending garbage */ | |
923 | debug("channel %d: decode socks4: too long", | |
924 | c->self); | |
925 | return -1; | |
926 | } | |
927 | } | |
928 | if (!found) | |
929 | return 0; | |
0490e609 | 930 | buffer_get(&c->input, (char *)&s4_req.version, 1); |
931 | buffer_get(&c->input, (char *)&s4_req.command, 1); | |
932 | buffer_get(&c->input, (char *)&s4_req.dest_port, 2); | |
28b9cb4d | 933 | buffer_get(&c->input, (char *)&s4_req.dest_addr, 4); |
53b8fe68 | 934 | have = buffer_len(&c->input); |
0490e609 | 935 | p = buffer_ptr(&c->input); |
936 | len = strlen(p); | |
6683b40f | 937 | debug2("channel %d: decode socks4: user %s/%d", c->self, p, len); |
0490e609 | 938 | if (len > have) |
28b9cb4d | 939 | fatal("channel %d: decode socks4: len %d > have %d", |
0490e609 | 940 | c->self, len, have); |
941 | strlcpy(username, p, sizeof(username)); | |
942 | buffer_consume(&c->input, len); | |
943 | buffer_consume(&c->input, 1); /* trailing '\0' */ | |
944 | ||
28b9cb4d | 945 | host = inet_ntoa(s4_req.dest_addr); |
0490e609 | 946 | strlcpy(c->path, host, sizeof(c->path)); |
947 | c->host_port = ntohs(s4_req.dest_port); | |
948 | ||
6683b40f | 949 | debug("channel %d: dynamic request: socks4 host %s port %u command %u", |
950 | c->self, host, c->host_port, s4_req.command); | |
0490e609 | 951 | |
28b9cb4d | 952 | if (s4_req.command != 1) { |
953 | debug("channel %d: cannot handle: socks4 cn %d", | |
954 | c->self, s4_req.command); | |
955 | return -1; | |
0490e609 | 956 | } |
28b9cb4d | 957 | s4_rsp.version = 0; /* vn: 0 for reply */ |
958 | s4_rsp.command = 90; /* cd: req granted */ | |
0490e609 | 959 | s4_rsp.dest_port = 0; /* ignored */ |
28b9cb4d | 960 | s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */ |
0490e609 | 961 | buffer_append(&c->output, (char *)&s4_rsp, sizeof(s4_rsp)); |
28b9cb4d | 962 | return 1; |
0490e609 | 963 | } |
964 | ||
28b9cb4d | 965 | /* dynamic port forwarding */ |
396c147e | 966 | static void |
28b9cb4d | 967 | channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset) |
968 | { | |
969 | u_char *p; | |
970 | int have, ret; | |
971 | ||
972 | have = buffer_len(&c->input); | |
973 | ||
974 | debug2("channel %d: pre_dynamic: have %d", c->self, have); | |
070adba2 | 975 | /* buffer_dump(&c->input); */ |
28b9cb4d | 976 | /* check if the fixed size part of the packet is in buffer. */ |
977 | if (have < 4) { | |
978 | /* need more */ | |
979 | FD_SET(c->sock, readset); | |
980 | return; | |
981 | } | |
982 | /* try to guess the protocol */ | |
983 | p = buffer_ptr(&c->input); | |
984 | switch (p[0]) { | |
6683b40f | 985 | case 0x04: |
986 | ret = channel_decode_socks4(c, readset, writeset); | |
987 | break; | |
28b9cb4d | 988 | default: |
989 | ret = -1; | |
990 | break; | |
991 | } | |
992 | if (ret < 0) { | |
719fc62f | 993 | chan_mark_dead(c); |
28b9cb4d | 994 | } else if (ret == 0) { |
995 | debug2("channel %d: pre_dynamic: need more", c->self); | |
996 | /* need more */ | |
997 | FD_SET(c->sock, readset); | |
998 | } else { | |
999 | /* switch to the next state */ | |
1000 | c->type = SSH_CHANNEL_OPENING; | |
1001 | port_open_helper(c, "direct-tcpip"); | |
1002 | } | |
1003 | } | |
0490e609 | 1004 | |
7368a6c8 | 1005 | /* This is our fake X11 server socket. */ |
396c147e | 1006 | static void |
7368a6c8 | 1007 | channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset) |
1008 | { | |
719fc62f | 1009 | Channel *nc; |
7368a6c8 | 1010 | struct sockaddr addr; |
719fc62f | 1011 | int newsock; |
7368a6c8 | 1012 | socklen_t addrlen; |
865ac82e | 1013 | char buf[16384], *remote_ipaddr; |
0b242b12 | 1014 | int remote_port; |
7368a6c8 | 1015 | |
1016 | if (FD_ISSET(c->sock, readset)) { | |
1017 | debug("X11 connection requested."); | |
1018 | addrlen = sizeof(addr); | |
1019 | newsock = accept(c->sock, &addr, &addrlen); | |
1020 | if (newsock < 0) { | |
1021 | error("accept: %.100s", strerror(errno)); | |
1022 | return; | |
5260325f | 1023 | } |
865ac82e | 1024 | remote_ipaddr = get_peer_ipaddr(newsock); |
0b242b12 | 1025 | remote_port = get_peer_port(newsock); |
7368a6c8 | 1026 | snprintf(buf, sizeof buf, "X11 connection from %.200s port %d", |
865ac82e | 1027 | remote_ipaddr, remote_port); |
0b242b12 | 1028 | |
719fc62f | 1029 | nc = channel_new("accepted x11 socket", |
0b242b12 | 1030 | SSH_CHANNEL_OPENING, newsock, newsock, -1, |
1031 | c->local_window_max, c->local_maxpacket, | |
a22aff1f | 1032 | 0, xstrdup(buf), 1); |
719fc62f | 1033 | if (nc == NULL) { |
1034 | close(newsock); | |
1035 | xfree(remote_ipaddr); | |
1036 | return; | |
1037 | } | |
0b242b12 | 1038 | if (compat20) { |
1039 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
1040 | packet_put_cstring("x11"); | |
719fc62f | 1041 | packet_put_int(nc->self); |
0b242b12 | 1042 | packet_put_int(c->local_window_max); |
1043 | packet_put_int(c->local_maxpacket); | |
865ac82e | 1044 | /* originator ipaddr and port */ |
1045 | packet_put_cstring(remote_ipaddr); | |
d0c832f3 | 1046 | if (datafellows & SSH_BUG_X11FWD) { |
1047 | debug("ssh2 x11 bug compat mode"); | |
1048 | } else { | |
1049 | packet_put_int(remote_port); | |
1050 | } | |
0b242b12 | 1051 | packet_send(); |
1052 | } else { | |
1053 | packet_start(SSH_SMSG_X11_OPEN); | |
719fc62f | 1054 | packet_put_int(nc->self); |
8e7895b8 | 1055 | if (packet_get_protocol_flags() & |
1056 | SSH_PROTOFLAG_HOST_IN_FWD_OPEN) | |
449c5ba5 | 1057 | packet_put_cstring(buf); |
0b242b12 | 1058 | packet_send(); |
1059 | } | |
865ac82e | 1060 | xfree(remote_ipaddr); |
8efc0c15 | 1061 | } |
8efc0c15 | 1062 | } |
1063 | ||
396c147e | 1064 | static void |
0490e609 | 1065 | port_open_helper(Channel *c, char *rtype) |
1066 | { | |
1067 | int direct; | |
1068 | char buf[1024]; | |
1069 | char *remote_ipaddr = get_peer_ipaddr(c->sock); | |
1070 | u_short remote_port = get_peer_port(c->sock); | |
1071 | ||
1072 | direct = (strcmp(rtype, "direct-tcpip") == 0); | |
1073 | ||
1074 | snprintf(buf, sizeof buf, | |
1075 | "%s: listening port %d for %.100s port %d, " | |
1076 | "connect from %.200s port %d", | |
1077 | rtype, c->listening_port, c->path, c->host_port, | |
1078 | remote_ipaddr, remote_port); | |
1079 | ||
1080 | xfree(c->remote_name); | |
1081 | c->remote_name = xstrdup(buf); | |
1082 | ||
1083 | if (compat20) { | |
1084 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
1085 | packet_put_cstring(rtype); | |
1086 | packet_put_int(c->self); | |
1087 | packet_put_int(c->local_window_max); | |
1088 | packet_put_int(c->local_maxpacket); | |
1089 | if (direct) { | |
1090 | /* target host, port */ | |
1091 | packet_put_cstring(c->path); | |
1092 | packet_put_int(c->host_port); | |
1093 | } else { | |
1094 | /* listen address, port */ | |
1095 | packet_put_cstring(c->path); | |
1096 | packet_put_int(c->listening_port); | |
1097 | } | |
1098 | /* originator host and port */ | |
1099 | packet_put_cstring(remote_ipaddr); | |
1100 | packet_put_int(remote_port); | |
1101 | packet_send(); | |
1102 | } else { | |
1103 | packet_start(SSH_MSG_PORT_OPEN); | |
1104 | packet_put_int(c->self); | |
1105 | packet_put_cstring(c->path); | |
1106 | packet_put_int(c->host_port); | |
8e7895b8 | 1107 | if (packet_get_protocol_flags() & |
1108 | SSH_PROTOFLAG_HOST_IN_FWD_OPEN) | |
0490e609 | 1109 | packet_put_cstring(c->remote_name); |
1110 | packet_send(); | |
1111 | } | |
1112 | xfree(remote_ipaddr); | |
1113 | } | |
1114 | ||
aa3378df | 1115 | /* |
7368a6c8 | 1116 | * This socket is listening for connections to a forwarded TCP/IP port. |
aa3378df | 1117 | */ |
396c147e | 1118 | static void |
7368a6c8 | 1119 | channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset) |
1120 | { | |
0490e609 | 1121 | Channel *nc; |
7368a6c8 | 1122 | struct sockaddr addr; |
719fc62f | 1123 | int newsock, nextstate; |
7368a6c8 | 1124 | socklen_t addrlen; |
0490e609 | 1125 | char *rtype; |
fa08c86b | 1126 | |
7368a6c8 | 1127 | if (FD_ISSET(c->sock, readset)) { |
1128 | debug("Connection to port %d forwarding " | |
1129 | "to %.100s port %d requested.", | |
1130 | c->listening_port, c->path, c->host_port); | |
0490e609 | 1131 | |
1132 | rtype = (c->type == SSH_CHANNEL_RPORT_LISTENER) ? | |
1133 | "forwarded-tcpip" : "direct-tcpip"; | |
97430469 | 1134 | nextstate = (c->host_port == 0 && |
1135 | c->type != SSH_CHANNEL_RPORT_LISTENER) ? | |
1136 | SSH_CHANNEL_DYNAMIC : SSH_CHANNEL_OPENING; | |
0490e609 | 1137 | |
7368a6c8 | 1138 | addrlen = sizeof(addr); |
1139 | newsock = accept(c->sock, &addr, &addrlen); | |
1140 | if (newsock < 0) { | |
1141 | error("accept: %.100s", strerror(errno)); | |
1142 | return; | |
1143 | } | |
719fc62f | 1144 | nc = channel_new(rtype, |
0490e609 | 1145 | nextstate, newsock, newsock, -1, |
7368a6c8 | 1146 | c->local_window_max, c->local_maxpacket, |
0490e609 | 1147 | 0, xstrdup(rtype), 1); |
0490e609 | 1148 | if (nc == NULL) { |
719fc62f | 1149 | error("channel_post_port_listener: no new channel:"); |
1150 | close(newsock); | |
0490e609 | 1151 | return; |
7368a6c8 | 1152 | } |
0490e609 | 1153 | nc->listening_port = c->listening_port; |
1154 | nc->host_port = c->host_port; | |
1155 | strlcpy(nc->path, c->path, sizeof(nc->path)); | |
1156 | ||
1157 | if (nextstate != SSH_CHANNEL_DYNAMIC) | |
1158 | port_open_helper(nc, rtype); | |
7368a6c8 | 1159 | } |
1160 | } | |
8efc0c15 | 1161 | |
7368a6c8 | 1162 | /* |
1163 | * This is the authentication agent socket listening for connections from | |
1164 | * clients. | |
1165 | */ | |
396c147e | 1166 | static void |
7368a6c8 | 1167 | channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset) |
8efc0c15 | 1168 | { |
719fc62f | 1169 | Channel *nc; |
8e7895b8 | 1170 | char *name; |
719fc62f | 1171 | int newsock; |
5260325f | 1172 | struct sockaddr addr; |
48e671d5 | 1173 | socklen_t addrlen; |
5260325f | 1174 | |
7368a6c8 | 1175 | if (FD_ISSET(c->sock, readset)) { |
1176 | addrlen = sizeof(addr); | |
1177 | newsock = accept(c->sock, &addr, &addrlen); | |
1178 | if (newsock < 0) { | |
1179 | error("accept from auth socket: %.100s", strerror(errno)); | |
1180 | return; | |
1181 | } | |
8e7895b8 | 1182 | name = xstrdup("accepted auth socket"); |
719fc62f | 1183 | nc = channel_new("accepted auth socket", |
fa08c86b | 1184 | SSH_CHANNEL_OPENING, newsock, newsock, -1, |
1185 | c->local_window_max, c->local_maxpacket, | |
8e7895b8 | 1186 | 0, name, 1); |
719fc62f | 1187 | if (nc == NULL) { |
1188 | error("channel_post_auth_listener: channel_new failed"); | |
8e7895b8 | 1189 | xfree(name); |
719fc62f | 1190 | close(newsock); |
1191 | } | |
fa08c86b | 1192 | if (compat20) { |
1193 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
1194 | packet_put_cstring("auth-agent@openssh.com"); | |
719fc62f | 1195 | packet_put_int(nc->self); |
fa08c86b | 1196 | packet_put_int(c->local_window_max); |
1197 | packet_put_int(c->local_maxpacket); | |
1198 | } else { | |
1199 | packet_start(SSH_SMSG_AGENT_OPEN); | |
719fc62f | 1200 | packet_put_int(nc->self); |
fa08c86b | 1201 | } |
7368a6c8 | 1202 | packet_send(); |
1203 | } | |
1204 | } | |
5260325f | 1205 | |
396c147e | 1206 | static void |
97fb6912 | 1207 | channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset) |
1208 | { | |
d18e0850 | 1209 | int err = 0; |
8ab2cb35 | 1210 | socklen_t sz = sizeof(err); |
d18e0850 | 1211 | |
97fb6912 | 1212 | if (FD_ISSET(c->sock, writeset)) { |
d18e0850 | 1213 | if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, (char *)&err, |
1214 | &sz) < 0) { | |
1215 | err = errno; | |
1216 | error("getsockopt SO_ERROR failed"); | |
1217 | } | |
1218 | if (err == 0) { | |
1219 | debug("channel %d: connected", c->self); | |
1220 | c->type = SSH_CHANNEL_OPEN; | |
1221 | if (compat20) { | |
1222 | packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1223 | packet_put_int(c->remote_id); | |
1224 | packet_put_int(c->self); | |
1225 | packet_put_int(c->local_window); | |
1226 | packet_put_int(c->local_maxpacket); | |
1227 | } else { | |
1228 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1229 | packet_put_int(c->remote_id); | |
1230 | packet_put_int(c->self); | |
1231 | } | |
97fb6912 | 1232 | } else { |
d18e0850 | 1233 | debug("channel %d: not connected: %s", |
1234 | c->self, strerror(err)); | |
1235 | if (compat20) { | |
1236 | packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE); | |
1237 | packet_put_int(c->remote_id); | |
1238 | packet_put_int(SSH2_OPEN_CONNECT_FAILED); | |
1239 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { | |
1240 | packet_put_cstring(strerror(err)); | |
1241 | packet_put_cstring(""); | |
1242 | } | |
97fb6912 | 1243 | } else { |
d18e0850 | 1244 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); |
1245 | packet_put_int(c->remote_id); | |
97fb6912 | 1246 | } |
d18e0850 | 1247 | chan_mark_dead(c); |
97fb6912 | 1248 | } |
d18e0850 | 1249 | packet_send(); |
97fb6912 | 1250 | } |
1251 | } | |
1252 | ||
396c147e | 1253 | static int |
7368a6c8 | 1254 | channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset) |
1255 | { | |
1256 | char buf[16*1024]; | |
1257 | int len; | |
1258 | ||
6fd8622b | 1259 | if (c->rfd != -1 && |
7368a6c8 | 1260 | FD_ISSET(c->rfd, readset)) { |
1261 | len = read(c->rfd, buf, sizeof(buf)); | |
0fbe8c74 | 1262 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1263 | return 1; | |
7368a6c8 | 1264 | if (len <= 0) { |
0b242b12 | 1265 | debug("channel %d: read<=0 rfd %d len %d", |
7368a6c8 | 1266 | c->self, c->rfd, len); |
28b9cb4d | 1267 | if (c->type != SSH_CHANNEL_OPEN) { |
1268 | debug("channel %d: not open", c->self); | |
719fc62f | 1269 | chan_mark_dead(c); |
0490e609 | 1270 | return -1; |
28b9cb4d | 1271 | } else if (compat13) { |
7368a6c8 | 1272 | buffer_consume(&c->output, buffer_len(&c->output)); |
1273 | c->type = SSH_CHANNEL_INPUT_DRAINING; | |
8e7895b8 | 1274 | debug("channel %d: input draining.", c->self); |
7368a6c8 | 1275 | } else { |
1276 | chan_read_failed(c); | |
5260325f | 1277 | } |
7368a6c8 | 1278 | return -1; |
1279 | } | |
2e73a022 | 1280 | if(c->input_filter != NULL) { |
1281 | if (c->input_filter(c, buf, len) == -1) { | |
070adba2 | 1282 | debug("channel %d: filter stops", c->self); |
2e73a022 | 1283 | chan_read_failed(c); |
1284 | } | |
1285 | } else { | |
1286 | buffer_append(&c->input, buf, len); | |
1287 | } | |
7368a6c8 | 1288 | } |
1289 | return 1; | |
1290 | } | |
396c147e | 1291 | static int |
7368a6c8 | 1292 | channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset) |
1293 | { | |
95ce5599 | 1294 | struct termios tio; |
780a9951 | 1295 | u_char *data; |
1296 | u_int dlen; | |
7368a6c8 | 1297 | int len; |
1298 | ||
1299 | /* Send buffered output data to the socket. */ | |
6fd8622b | 1300 | if (c->wfd != -1 && |
7368a6c8 | 1301 | FD_ISSET(c->wfd, writeset) && |
1302 | buffer_len(&c->output) > 0) { | |
780a9951 | 1303 | data = buffer_ptr(&c->output); |
1304 | dlen = buffer_len(&c->output); | |
1305 | len = write(c->wfd, data, dlen); | |
0fbe8c74 | 1306 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1307 | return 1; | |
7368a6c8 | 1308 | if (len <= 0) { |
28b9cb4d | 1309 | if (c->type != SSH_CHANNEL_OPEN) { |
1310 | debug("channel %d: not open", c->self); | |
719fc62f | 1311 | chan_mark_dead(c); |
28b9cb4d | 1312 | return -1; |
1313 | } else if (compat13) { | |
7368a6c8 | 1314 | buffer_consume(&c->output, buffer_len(&c->output)); |
8e7895b8 | 1315 | debug("channel %d: input draining.", c->self); |
7368a6c8 | 1316 | c->type = SSH_CHANNEL_INPUT_DRAINING; |
1317 | } else { | |
1318 | chan_write_failed(c); | |
5260325f | 1319 | } |
7368a6c8 | 1320 | return -1; |
1321 | } | |
780a9951 | 1322 | if (compat20 && c->isatty && dlen >= 1 && data[0] != '\r') { |
0ae4fe1d | 1323 | if (tcgetattr(c->wfd, &tio) == 0 && |
1324 | !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) { | |
1325 | /* | |
1326 | * Simulate echo to reduce the impact of | |
355724fc | 1327 | * traffic analysis. We need to match the |
95ce5599 | 1328 | * size of a SSH2_MSG_CHANNEL_DATA message |
1329 | * (4 byte channel id + data) | |
0ae4fe1d | 1330 | */ |
95ce5599 | 1331 | packet_send_ignore(4 + len); |
0ae4fe1d | 1332 | packet_send(); |
0ae4fe1d | 1333 | } |
1334 | } | |
7368a6c8 | 1335 | buffer_consume(&c->output, len); |
7e7327a1 | 1336 | if (compat20 && len > 0) { |
1337 | c->local_consumed += len; | |
1338 | } | |
1339 | } | |
1340 | return 1; | |
1341 | } | |
396c147e | 1342 | static int |
7e7327a1 | 1343 | channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset) |
1344 | { | |
1345 | char buf[16*1024]; | |
1346 | int len; | |
1347 | ||
8ce64345 | 1348 | /** XXX handle drain efd, too */ |
7e7327a1 | 1349 | if (c->efd != -1) { |
1350 | if (c->extended_usage == CHAN_EXTENDED_WRITE && | |
1351 | FD_ISSET(c->efd, writeset) && | |
1352 | buffer_len(&c->extended) > 0) { | |
1353 | len = write(c->efd, buffer_ptr(&c->extended), | |
1354 | buffer_len(&c->extended)); | |
de273eef | 1355 | debug2("channel %d: written %d to efd %d", |
7e7327a1 | 1356 | c->self, len, c->efd); |
ee55dacf | 1357 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1358 | return 1; | |
1359 | if (len <= 0) { | |
1360 | debug2("channel %d: closing write-efd %d", | |
1361 | c->self, c->efd); | |
489aa2e9 | 1362 | channel_close_fd(&c->efd); |
ee55dacf | 1363 | } else { |
7e7327a1 | 1364 | buffer_consume(&c->extended, len); |
1365 | c->local_consumed += len; | |
1366 | } | |
1367 | } else if (c->extended_usage == CHAN_EXTENDED_READ && | |
1368 | FD_ISSET(c->efd, readset)) { | |
1369 | len = read(c->efd, buf, sizeof(buf)); | |
de273eef | 1370 | debug2("channel %d: read %d from efd %d", |
7e7327a1 | 1371 | c->self, len, c->efd); |
ee55dacf | 1372 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1373 | return 1; | |
1374 | if (len <= 0) { | |
1375 | debug2("channel %d: closing read-efd %d", | |
8ce64345 | 1376 | c->self, c->efd); |
489aa2e9 | 1377 | channel_close_fd(&c->efd); |
ee55dacf | 1378 | } else { |
7e7327a1 | 1379 | buffer_append(&c->extended, buf, len); |
ee55dacf | 1380 | } |
7e7327a1 | 1381 | } |
1382 | } | |
1383 | return 1; | |
1384 | } | |
396c147e | 1385 | static int |
ee55dacf | 1386 | channel_check_window(Channel *c) |
7e7327a1 | 1387 | { |
28b9cb4d | 1388 | if (c->type == SSH_CHANNEL_OPEN && |
1389 | !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) && | |
7e7327a1 | 1390 | c->local_window < c->local_window_max/2 && |
1391 | c->local_consumed > 0) { | |
1392 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); | |
1393 | packet_put_int(c->remote_id); | |
1394 | packet_put_int(c->local_consumed); | |
1395 | packet_send(); | |
de273eef | 1396 | debug2("channel %d: window %d sent adjust %d", |
7e7327a1 | 1397 | c->self, c->local_window, |
1398 | c->local_consumed); | |
1399 | c->local_window += c->local_consumed; | |
1400 | c->local_consumed = 0; | |
7368a6c8 | 1401 | } |
1402 | return 1; | |
1403 | } | |
5260325f | 1404 | |
396c147e | 1405 | static void |
7368a6c8 | 1406 | channel_post_open_1(Channel *c, fd_set * readset, fd_set * writeset) |
1407 | { | |
1408 | channel_handle_rfd(c, readset, writeset); | |
1409 | channel_handle_wfd(c, readset, writeset); | |
1410 | } | |
aa3378df | 1411 | |
396c147e | 1412 | static void |
7e7327a1 | 1413 | channel_post_open_2(Channel *c, fd_set * readset, fd_set * writeset) |
1414 | { | |
1415 | channel_handle_rfd(c, readset, writeset); | |
1416 | channel_handle_wfd(c, readset, writeset); | |
1417 | channel_handle_efd(c, readset, writeset); | |
ee55dacf | 1418 | |
1419 | channel_check_window(c); | |
7e7327a1 | 1420 | } |
1421 | ||
396c147e | 1422 | static void |
7368a6c8 | 1423 | channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset) |
1424 | { | |
1425 | int len; | |
1426 | /* Send buffered output data to the socket. */ | |
1427 | if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) { | |
1428 | len = write(c->sock, buffer_ptr(&c->output), | |
1429 | buffer_len(&c->output)); | |
1430 | if (len <= 0) | |
1431 | buffer_consume(&c->output, buffer_len(&c->output)); | |
1432 | else | |
1433 | buffer_consume(&c->output, len); | |
1434 | } | |
1435 | } | |
5260325f | 1436 | |
396c147e | 1437 | static void |
7e7327a1 | 1438 | channel_handler_init_20(void) |
1439 | { | |
1440 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_20; | |
0b242b12 | 1441 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; |
7e7327a1 | 1442 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; |
fa08c86b | 1443 | channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener; |
0b242b12 | 1444 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; |
fa08c86b | 1445 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; |
97fb6912 | 1446 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1447 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7e7327a1 | 1448 | |
1449 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_2; | |
1450 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
fa08c86b | 1451 | channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener; |
0b242b12 | 1452 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; |
fa08c86b | 1453 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; |
97fb6912 | 1454 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
28b9cb4d | 1455 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_2; |
7e7327a1 | 1456 | } |
1457 | ||
396c147e | 1458 | static void |
7368a6c8 | 1459 | channel_handler_init_13(void) |
1460 | { | |
1461 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13; | |
1462 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13; | |
1463 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; | |
1464 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; | |
1465 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; | |
1466 | channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining; | |
1467 | channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining; | |
97fb6912 | 1468 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1469 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7368a6c8 | 1470 | |
1471 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1; | |
1472 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; | |
1473 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
1474 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; | |
1475 | channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13; | |
97fb6912 | 1476 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
28b9cb4d | 1477 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1; |
7368a6c8 | 1478 | } |
5260325f | 1479 | |
396c147e | 1480 | static void |
7368a6c8 | 1481 | channel_handler_init_15(void) |
1482 | { | |
1483 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_15; | |
0b242b12 | 1484 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; |
7368a6c8 | 1485 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; |
1486 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; | |
1487 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; | |
97fb6912 | 1488 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1489 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7368a6c8 | 1490 | |
1491 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; | |
1492 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
1493 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; | |
1494 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1; | |
97fb6912 | 1495 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
28b9cb4d | 1496 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1; |
7368a6c8 | 1497 | } |
1498 | ||
396c147e | 1499 | static void |
7368a6c8 | 1500 | channel_handler_init(void) |
1501 | { | |
1502 | int i; | |
1503 | for(i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) { | |
1504 | channel_pre[i] = NULL; | |
1505 | channel_post[i] = NULL; | |
1506 | } | |
7e7327a1 | 1507 | if (compat20) |
1508 | channel_handler_init_20(); | |
1509 | else if (compat13) | |
7368a6c8 | 1510 | channel_handler_init_13(); |
1511 | else | |
1512 | channel_handler_init_15(); | |
1513 | } | |
1514 | ||
396c147e | 1515 | static void |
7368a6c8 | 1516 | channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset) |
1517 | { | |
1518 | static int did_init = 0; | |
1519 | int i; | |
1520 | Channel *c; | |
1521 | ||
1522 | if (!did_init) { | |
1523 | channel_handler_init(); | |
1524 | did_init = 1; | |
1525 | } | |
1526 | for (i = 0; i < channels_alloc; i++) { | |
719fc62f | 1527 | c = channels[i]; |
1528 | if (c == NULL) | |
5260325f | 1529 | continue; |
6fd8622b | 1530 | if (ftab[c->type] != NULL) |
1531 | (*ftab[c->type])(c, readset, writeset); | |
ee55dacf | 1532 | if (chan_is_dead(c)) { |
1533 | /* | |
1534 | * we have to remove the fd's from the select mask | |
1535 | * before the channels are free'd and the fd's are | |
1536 | * closed | |
1537 | */ | |
1538 | if (c->wfd != -1) | |
1539 | FD_CLR(c->wfd, writeset); | |
1540 | if (c->rfd != -1) | |
1541 | FD_CLR(c->rfd, readset); | |
1542 | if (c->efd != -1) { | |
1543 | if (c->extended_usage == CHAN_EXTENDED_READ) | |
1544 | FD_CLR(c->efd, readset); | |
1545 | if (c->extended_usage == CHAN_EXTENDED_WRITE) | |
1546 | FD_CLR(c->efd, writeset); | |
1547 | } | |
719fc62f | 1548 | channel_free(c); |
ee55dacf | 1549 | } |
8efc0c15 | 1550 | } |
8efc0c15 | 1551 | } |
1552 | ||
8e7895b8 | 1553 | /* |
1554 | * Allocate/update select bitmasks and add any bits relevant to channels in | |
1555 | * select bitmasks. | |
1556 | */ | |
6ae2364d | 1557 | void |
c422989b | 1558 | channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp, |
489aa2e9 | 1559 | int *nallocp, int rekeying) |
7368a6c8 | 1560 | { |
39929cdb | 1561 | int n; |
1562 | u_int sz; | |
1563 | ||
1564 | n = MAX(*maxfdp, channel_max_fd); | |
1565 | ||
1566 | sz = howmany(n+1, NFDBITS) * sizeof(fd_mask); | |
489aa2e9 | 1567 | /* perhaps check sz < nalloc/2 and shrink? */ |
1568 | if (*readsetp == NULL || sz > *nallocp) { | |
1569 | *readsetp = xrealloc(*readsetp, sz); | |
1570 | *writesetp = xrealloc(*writesetp, sz); | |
1571 | *nallocp = sz; | |
39929cdb | 1572 | } |
489aa2e9 | 1573 | *maxfdp = n; |
39929cdb | 1574 | memset(*readsetp, 0, sz); |
1575 | memset(*writesetp, 0, sz); | |
1576 | ||
c422989b | 1577 | if (!rekeying) |
1578 | channel_handler(channel_pre, *readsetp, *writesetp); | |
7368a6c8 | 1579 | } |
1580 | ||
8e7895b8 | 1581 | /* |
1582 | * After select, perform any appropriate operations for channels which have | |
1583 | * events pending. | |
1584 | */ | |
6ae2364d | 1585 | void |
7368a6c8 | 1586 | channel_after_select(fd_set * readset, fd_set * writeset) |
1587 | { | |
1588 | channel_handler(channel_post, readset, writeset); | |
1589 | } | |
1590 | ||
8e7895b8 | 1591 | |
39929cdb | 1592 | /* If there is data to send to the connection, enqueue some of it now. */ |
8efc0c15 | 1593 | |
6ae2364d | 1594 | void |
5260325f | 1595 | channel_output_poll() |
8efc0c15 | 1596 | { |
5260325f | 1597 | int len, i; |
7368a6c8 | 1598 | Channel *c; |
5260325f | 1599 | |
1600 | for (i = 0; i < channels_alloc; i++) { | |
719fc62f | 1601 | c = channels[i]; |
1602 | if (c == NULL) | |
1603 | continue; | |
48e671d5 | 1604 | |
8e7895b8 | 1605 | /* |
1606 | * We are only interested in channels that can have buffered | |
1607 | * incoming data. | |
1608 | */ | |
48e671d5 | 1609 | if (compat13) { |
7368a6c8 | 1610 | if (c->type != SSH_CHANNEL_OPEN && |
1611 | c->type != SSH_CHANNEL_INPUT_DRAINING) | |
48e671d5 | 1612 | continue; |
1613 | } else { | |
7368a6c8 | 1614 | if (c->type != SSH_CHANNEL_OPEN) |
48e671d5 | 1615 | continue; |
48e671d5 | 1616 | } |
e78a59f5 | 1617 | if (compat20 && |
1618 | (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) { | |
ee55dacf | 1619 | /* XXX is this true? */ |
61f8a1d1 | 1620 | debug2("channel %d: no data after CLOSE", c->self); |
7e7327a1 | 1621 | continue; |
1622 | } | |
5260325f | 1623 | |
1624 | /* Get the amount of buffered data for this channel. */ | |
ee55dacf | 1625 | if ((c->istate == CHAN_INPUT_OPEN || |
1626 | c->istate == CHAN_INPUT_WAIT_DRAIN) && | |
1627 | (len = buffer_len(&c->input)) > 0) { | |
8e7895b8 | 1628 | /* |
1629 | * Send some data for the other side over the secure | |
1630 | * connection. | |
1631 | */ | |
7e7327a1 | 1632 | if (compat20) { |
1633 | if (len > c->remote_window) | |
1634 | len = c->remote_window; | |
1635 | if (len > c->remote_maxpacket) | |
1636 | len = c->remote_maxpacket; | |
5260325f | 1637 | } else { |
7e7327a1 | 1638 | if (packet_is_interactive()) { |
1639 | if (len > 1024) | |
1640 | len = 512; | |
1641 | } else { | |
1642 | /* Keep the packets at reasonable size. */ | |
1643 | if (len > packet_get_maxsize()/2) | |
1644 | len = packet_get_maxsize()/2; | |
1645 | } | |
5260325f | 1646 | } |
7368a6c8 | 1647 | if (len > 0) { |
7e7327a1 | 1648 | packet_start(compat20 ? |
1649 | SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA); | |
7368a6c8 | 1650 | packet_put_int(c->remote_id); |
1651 | packet_put_string(buffer_ptr(&c->input), len); | |
1652 | packet_send(); | |
1653 | buffer_consume(&c->input, len); | |
1654 | c->remote_window -= len; | |
7368a6c8 | 1655 | } |
1656 | } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) { | |
5260325f | 1657 | if (compat13) |
1658 | fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3"); | |
aa3378df | 1659 | /* |
1660 | * input-buffer is empty and read-socket shutdown: | |
1661 | * tell peer, that we will not send more data: send IEOF | |
1662 | */ | |
7368a6c8 | 1663 | chan_ibuf_empty(c); |
5260325f | 1664 | } |
7e7327a1 | 1665 | /* Send extended data, i.e. stderr */ |
1666 | if (compat20 && | |
1667 | c->remote_window > 0 && | |
1668 | (len = buffer_len(&c->extended)) > 0 && | |
1669 | c->extended_usage == CHAN_EXTENDED_READ) { | |
ee55dacf | 1670 | debug2("channel %d: rwin %d elen %d euse %d", |
1671 | c->self, c->remote_window, buffer_len(&c->extended), | |
1672 | c->extended_usage); | |
7e7327a1 | 1673 | if (len > c->remote_window) |
1674 | len = c->remote_window; | |
1675 | if (len > c->remote_maxpacket) | |
1676 | len = c->remote_maxpacket; | |
1677 | packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA); | |
1678 | packet_put_int(c->remote_id); | |
1679 | packet_put_int(SSH2_EXTENDED_DATA_STDERR); | |
1680 | packet_put_string(buffer_ptr(&c->extended), len); | |
1681 | packet_send(); | |
1682 | buffer_consume(&c->extended, len); | |
1683 | c->remote_window -= len; | |
ee55dacf | 1684 | debug2("channel %d: sent ext data %d", c->self, len); |
7e7327a1 | 1685 | } |
8efc0c15 | 1686 | } |
8efc0c15 | 1687 | } |
1688 | ||
8e7895b8 | 1689 | |
1690 | /* -- protocol input */ | |
8efc0c15 | 1691 | |
6ae2364d | 1692 | void |
188adeb2 | 1693 | channel_input_data(int type, int plen, void *ctxt) |
8efc0c15 | 1694 | { |
48e671d5 | 1695 | int id; |
5260325f | 1696 | char *data; |
1e3b8b07 | 1697 | u_int data_len; |
7368a6c8 | 1698 | Channel *c; |
5260325f | 1699 | |
1700 | /* Get the channel number and verify it. */ | |
48e671d5 | 1701 | id = packet_get_int(); |
7368a6c8 | 1702 | c = channel_lookup(id); |
1703 | if (c == NULL) | |
48e671d5 | 1704 | packet_disconnect("Received data for nonexistent channel %d.", id); |
5260325f | 1705 | |
1706 | /* Ignore any data for non-open channels (might happen on close) */ | |
7368a6c8 | 1707 | if (c->type != SSH_CHANNEL_OPEN && |
1708 | c->type != SSH_CHANNEL_X11_OPEN) | |
48e671d5 | 1709 | return; |
1710 | ||
1711 | /* same for protocol 1.5 if output end is no longer open */ | |
7368a6c8 | 1712 | if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) |
5260325f | 1713 | return; |
1714 | ||
1715 | /* Get the data. */ | |
1716 | data = packet_get_string(&data_len); | |
6ae2364d | 1717 | packet_done(); |
7368a6c8 | 1718 | |
7e7327a1 | 1719 | if (compat20){ |
1720 | if (data_len > c->local_maxpacket) { | |
1721 | log("channel %d: rcvd big packet %d, maxpack %d", | |
1722 | c->self, data_len, c->local_maxpacket); | |
1723 | } | |
1724 | if (data_len > c->local_window) { | |
1725 | log("channel %d: rcvd too much data %d, win %d", | |
1726 | c->self, data_len, c->local_window); | |
1727 | xfree(data); | |
1728 | return; | |
1729 | } | |
1730 | c->local_window -= data_len; | |
1731 | }else{ | |
1732 | packet_integrity_check(plen, 4 + 4 + data_len, type); | |
1733 | } | |
7368a6c8 | 1734 | buffer_append(&c->output, data, data_len); |
5260325f | 1735 | xfree(data); |
8efc0c15 | 1736 | } |
8e7895b8 | 1737 | |
6ae2364d | 1738 | void |
188adeb2 | 1739 | channel_input_extended_data(int type, int plen, void *ctxt) |
7e7327a1 | 1740 | { |
1741 | int id; | |
1742 | int tcode; | |
1743 | char *data; | |
1e3b8b07 | 1744 | u_int data_len; |
7e7327a1 | 1745 | Channel *c; |
1746 | ||
1747 | /* Get the channel number and verify it. */ | |
1748 | id = packet_get_int(); | |
1749 | c = channel_lookup(id); | |
1750 | ||
1751 | if (c == NULL) | |
1752 | packet_disconnect("Received extended_data for bad channel %d.", id); | |
1753 | if (c->type != SSH_CHANNEL_OPEN) { | |
1754 | log("channel %d: ext data for non open", id); | |
1755 | return; | |
1756 | } | |
1757 | tcode = packet_get_int(); | |
1758 | if (c->efd == -1 || | |
1759 | c->extended_usage != CHAN_EXTENDED_WRITE || | |
1760 | tcode != SSH2_EXTENDED_DATA_STDERR) { | |
1761 | log("channel %d: bad ext data", c->self); | |
1762 | return; | |
1763 | } | |
1764 | data = packet_get_string(&data_len); | |
6ae2364d | 1765 | packet_done(); |
7e7327a1 | 1766 | if (data_len > c->local_window) { |
1767 | log("channel %d: rcvd too much extended_data %d, win %d", | |
1768 | c->self, data_len, c->local_window); | |
1769 | xfree(data); | |
1770 | return; | |
1771 | } | |
de273eef | 1772 | debug2("channel %d: rcvd ext data %d", c->self, data_len); |
7e7327a1 | 1773 | c->local_window -= data_len; |
1774 | buffer_append(&c->extended, data, data_len); | |
1775 | xfree(data); | |
1776 | } | |
1777 | ||
6ae2364d | 1778 | void |
188adeb2 | 1779 | channel_input_ieof(int type, int plen, void *ctxt) |
7368a6c8 | 1780 | { |
1781 | int id; | |
1782 | Channel *c; | |
1783 | ||
1784 | packet_integrity_check(plen, 4, type); | |
1785 | ||
1786 | id = packet_get_int(); | |
1787 | c = channel_lookup(id); | |
1788 | if (c == NULL) | |
1789 | packet_disconnect("Received ieof for nonexistent channel %d.", id); | |
1790 | chan_rcvd_ieof(c); | |
a5f82435 | 1791 | |
1792 | /* XXX force input close */ | |
1793 | if (c->force_drain) { | |
1794 | debug("channel %d: FORCE input drain", c->self); | |
1795 | c->istate = CHAN_INPUT_WAIT_DRAIN; | |
1796 | } | |
1797 | ||
7368a6c8 | 1798 | } |
8efc0c15 | 1799 | |
6ae2364d | 1800 | void |
188adeb2 | 1801 | channel_input_close(int type, int plen, void *ctxt) |
8efc0c15 | 1802 | { |
7368a6c8 | 1803 | int id; |
1804 | Channel *c; | |
5260325f | 1805 | |
7368a6c8 | 1806 | packet_integrity_check(plen, 4, type); |
1807 | ||
1808 | id = packet_get_int(); | |
1809 | c = channel_lookup(id); | |
1810 | if (c == NULL) | |
1811 | packet_disconnect("Received close for nonexistent channel %d.", id); | |
aa3378df | 1812 | |
1813 | /* | |
1814 | * Send a confirmation that we have closed the channel and no more | |
1815 | * data is coming for it. | |
1816 | */ | |
5260325f | 1817 | packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION); |
7368a6c8 | 1818 | packet_put_int(c->remote_id); |
5260325f | 1819 | packet_send(); |
1820 | ||
aa3378df | 1821 | /* |
1822 | * If the channel is in closed state, we have sent a close request, | |
1823 | * and the other side will eventually respond with a confirmation. | |
1824 | * Thus, we cannot free the channel here, because then there would be | |
1825 | * no-one to receive the confirmation. The channel gets freed when | |
1826 | * the confirmation arrives. | |
1827 | */ | |
7368a6c8 | 1828 | if (c->type != SSH_CHANNEL_CLOSED) { |
aa3378df | 1829 | /* |
1830 | * Not a closed channel - mark it as draining, which will | |
1831 | * cause it to be freed later. | |
1832 | */ | |
7368a6c8 | 1833 | buffer_consume(&c->input, buffer_len(&c->input)); |
1834 | c->type = SSH_CHANNEL_OUTPUT_DRAINING; | |
5260325f | 1835 | } |
8efc0c15 | 1836 | } |
1837 | ||
7368a6c8 | 1838 | /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */ |
6ae2364d | 1839 | void |
188adeb2 | 1840 | channel_input_oclose(int type, int plen, void *ctxt) |
8efc0c15 | 1841 | { |
7368a6c8 | 1842 | int id = packet_get_int(); |
1843 | Channel *c = channel_lookup(id); | |
1844 | packet_integrity_check(plen, 4, type); | |
1845 | if (c == NULL) | |
1846 | packet_disconnect("Received oclose for nonexistent channel %d.", id); | |
1847 | chan_rcvd_oclose(c); | |
8efc0c15 | 1848 | } |
1849 | ||
6ae2364d | 1850 | void |
188adeb2 | 1851 | channel_input_close_confirmation(int type, int plen, void *ctxt) |
7368a6c8 | 1852 | { |
1853 | int id = packet_get_int(); | |
1854 | Channel *c = channel_lookup(id); | |
1855 | ||
6ae2364d | 1856 | packet_done(); |
7368a6c8 | 1857 | if (c == NULL) |
1858 | packet_disconnect("Received close confirmation for " | |
1859 | "out-of-range channel %d.", id); | |
1860 | if (c->type != SSH_CHANNEL_CLOSED) | |
1861 | packet_disconnect("Received close confirmation for " | |
1862 | "non-closed channel %d (type %d).", id, c->type); | |
719fc62f | 1863 | channel_free(c); |
7368a6c8 | 1864 | } |
8efc0c15 | 1865 | |
6ae2364d | 1866 | void |
188adeb2 | 1867 | channel_input_open_confirmation(int type, int plen, void *ctxt) |
8efc0c15 | 1868 | { |
7368a6c8 | 1869 | int id, remote_id; |
1870 | Channel *c; | |
5260325f | 1871 | |
7e7327a1 | 1872 | if (!compat20) |
1873 | packet_integrity_check(plen, 4 + 4, type); | |
5260325f | 1874 | |
7368a6c8 | 1875 | id = packet_get_int(); |
1876 | c = channel_lookup(id); | |
5260325f | 1877 | |
7368a6c8 | 1878 | if (c==NULL || c->type != SSH_CHANNEL_OPENING) |
1879 | packet_disconnect("Received open confirmation for " | |
1880 | "non-opening channel %d.", id); | |
1881 | remote_id = packet_get_int(); | |
aa3378df | 1882 | /* Record the remote channel number and mark that the channel is now open. */ |
7368a6c8 | 1883 | c->remote_id = remote_id; |
1884 | c->type = SSH_CHANNEL_OPEN; | |
7e7327a1 | 1885 | |
1886 | if (compat20) { | |
1887 | c->remote_window = packet_get_int(); | |
1888 | c->remote_maxpacket = packet_get_int(); | |
6ae2364d | 1889 | packet_done(); |
7e7327a1 | 1890 | if (c->cb_fn != NULL && c->cb_event == type) { |
de273eef | 1891 | debug2("callback start"); |
7e7327a1 | 1892 | c->cb_fn(c->self, c->cb_arg); |
de273eef | 1893 | debug2("callback done"); |
7e7327a1 | 1894 | } |
1895 | debug("channel %d: open confirm rwindow %d rmax %d", c->self, | |
1896 | c->remote_window, c->remote_maxpacket); | |
1897 | } | |
8efc0c15 | 1898 | } |
1899 | ||
396c147e | 1900 | static char * |
d18e0850 | 1901 | reason2txt(int reason) |
1902 | { | |
1903 | switch(reason) { | |
1904 | case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED: | |
1905 | return "administratively prohibited"; | |
1906 | case SSH2_OPEN_CONNECT_FAILED: | |
1907 | return "connect failed"; | |
1908 | case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE: | |
1909 | return "unknown channel type"; | |
1910 | case SSH2_OPEN_RESOURCE_SHORTAGE: | |
1911 | return "resource shortage"; | |
1912 | } | |
7e8c18e9 | 1913 | return "unknown reason"; |
d18e0850 | 1914 | } |
1915 | ||
6ae2364d | 1916 | void |
188adeb2 | 1917 | channel_input_open_failure(int type, int plen, void *ctxt) |
8efc0c15 | 1918 | { |
02a024dd | 1919 | int id, reason; |
1920 | char *msg = NULL, *lang = NULL; | |
7368a6c8 | 1921 | Channel *c; |
5260325f | 1922 | |
7e7327a1 | 1923 | if (!compat20) |
1924 | packet_integrity_check(plen, 4, type); | |
7368a6c8 | 1925 | |
1926 | id = packet_get_int(); | |
1927 | c = channel_lookup(id); | |
1928 | ||
1929 | if (c==NULL || c->type != SSH_CHANNEL_OPENING) | |
1930 | packet_disconnect("Received open failure for " | |
1931 | "non-opening channel %d.", id); | |
7e7327a1 | 1932 | if (compat20) { |
02a024dd | 1933 | reason = packet_get_int(); |
fbe90f7b | 1934 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { |
02a024dd | 1935 | msg = packet_get_string(NULL); |
1936 | lang = packet_get_string(NULL); | |
1937 | } | |
6ae2364d | 1938 | packet_done(); |
d18e0850 | 1939 | log("channel %d: open failed: %s%s%s", id, |
1940 | reason2txt(reason), msg ? ": ": "", msg ? msg : ""); | |
02a024dd | 1941 | if (msg != NULL) |
1942 | xfree(msg); | |
1943 | if (lang != NULL) | |
1944 | xfree(lang); | |
7e7327a1 | 1945 | } |
5260325f | 1946 | /* Free the channel. This will also close the socket. */ |
719fc62f | 1947 | channel_free(c); |
8efc0c15 | 1948 | } |
1949 | ||
7e7327a1 | 1950 | void |
188adeb2 | 1951 | channel_input_channel_request(int type, int plen, void *ctxt) |
7e7327a1 | 1952 | { |
1953 | int id; | |
1954 | Channel *c; | |
1955 | ||
1956 | id = packet_get_int(); | |
1957 | c = channel_lookup(id); | |
1958 | ||
1959 | if (c == NULL || | |
1960 | (c->type != SSH_CHANNEL_OPEN && c->type != SSH_CHANNEL_LARVAL)) | |
1961 | packet_disconnect("Received request for " | |
1962 | "non-open channel %d.", id); | |
1963 | if (c->cb_fn != NULL && c->cb_event == type) { | |
de273eef | 1964 | debug2("callback start"); |
7e7327a1 | 1965 | c->cb_fn(c->self, c->cb_arg); |
de273eef | 1966 | debug2("callback done"); |
8e7895b8 | 1967 | } else { |
1968 | char *service = packet_get_string(NULL); | |
1969 | debug("channel %d: rcvd request for %s", c->self, service); | |
1970 | debug("cb_fn %p cb_event %d", c->cb_fn , c->cb_event); | |
1971 | xfree(service); | |
719fc62f | 1972 | } |
3ffc6336 | 1973 | } |
1974 | ||
8e7895b8 | 1975 | void |
1976 | channel_input_window_adjust(int type, int plen, void *ctxt) | |
1977 | { | |
1978 | Channel *c; | |
1979 | int id, adjust; | |
3ffc6336 | 1980 | |
8e7895b8 | 1981 | if (!compat20) |
1982 | return; | |
8efc0c15 | 1983 | |
8e7895b8 | 1984 | /* Get the channel number and verify it. */ |
1985 | id = packet_get_int(); | |
1986 | c = channel_lookup(id); | |
1987 | ||
1988 | if (c == NULL || c->type != SSH_CHANNEL_OPEN) { | |
1989 | log("Received window adjust for " | |
1990 | "non-open channel %d.", id); | |
1991 | return; | |
1992 | } | |
1993 | adjust = packet_get_int(); | |
1994 | packet_done(); | |
1995 | debug2("channel %d: rcvd adjust %d", id, adjust); | |
1996 | c->remote_window += adjust; | |
1997 | } | |
1998 | ||
1999 | void | |
2000 | channel_input_port_open(int type, int plen, void *ctxt) | |
8efc0c15 | 2001 | { |
8e7895b8 | 2002 | Channel *c = NULL; |
2003 | u_short host_port; | |
2004 | char *host, *originator_string; | |
2005 | int remote_id, sock = -1; | |
5260325f | 2006 | |
8e7895b8 | 2007 | remote_id = packet_get_int(); |
2008 | host = packet_get_string(NULL); | |
2009 | host_port = packet_get_int(); | |
2010 | ||
2011 | if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) { | |
2012 | originator_string = packet_get_string(NULL); | |
2013 | } else { | |
2014 | originator_string = xstrdup("unknown (remote did not supply name)"); | |
2015 | } | |
2016 | packet_done(); | |
2017 | sock = channel_connect_to(host, host_port); | |
2018 | if (sock != -1) { | |
2019 | c = channel_new("connected socket", | |
2020 | SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0, | |
2021 | originator_string, 1); | |
2022 | if (c == NULL) { | |
2023 | error("channel_input_port_open: channel_new failed"); | |
2024 | close(sock); | |
2025 | } else { | |
2026 | c->remote_id = remote_id; | |
5260325f | 2027 | } |
2028 | } | |
8e7895b8 | 2029 | if (c == NULL) { |
2030 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
2031 | packet_put_int(remote_id); | |
2032 | packet_send(); | |
2033 | } | |
2034 | xfree(host); | |
8efc0c15 | 2035 | } |
2036 | ||
8e7895b8 | 2037 | |
2038 | /* -- tcp forwarding */ | |
2039 | ||
aa3378df | 2040 | /* |
2041 | * Initiate forwarding of connections to local port "port" through the secure | |
2042 | * channel to host:port from remote side. | |
2043 | */ | |
02a024dd | 2044 | int |
fa08c86b | 2045 | channel_request_local_forwarding(u_short listen_port, const char *host_to_connect, |
2046 | u_short port_to_connect, int gateway_ports) | |
2047 | { | |
02a024dd | 2048 | return channel_request_forwarding( |
fa08c86b | 2049 | NULL, listen_port, |
2050 | host_to_connect, port_to_connect, | |
2051 | gateway_ports, /*remote_fwd*/ 0); | |
2052 | } | |
8efc0c15 | 2053 | |
fa08c86b | 2054 | /* |
2055 | * If 'remote_fwd' is true we have a '-R style' listener for protocol 2 | |
2056 | * (SSH_CHANNEL_RPORT_LISTENER). | |
2057 | */ | |
02a024dd | 2058 | int |
fa08c86b | 2059 | channel_request_forwarding( |
2060 | const char *listen_address, u_short listen_port, | |
2061 | const char *host_to_connect, u_short port_to_connect, | |
2062 | int gateway_ports, int remote_fwd) | |
8efc0c15 | 2063 | { |
719fc62f | 2064 | Channel *c; |
8e7895b8 | 2065 | int success, sock, on = 1, type; |
48e671d5 | 2066 | struct addrinfo hints, *ai, *aitop; |
2067 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; | |
fa08c86b | 2068 | const char *host; |
aa3378df | 2069 | struct linger linger; |
5260325f | 2070 | |
02a024dd | 2071 | success = 0; |
2072 | ||
fa08c86b | 2073 | if (remote_fwd) { |
2074 | host = listen_address; | |
8e7895b8 | 2075 | type = SSH_CHANNEL_RPORT_LISTENER; |
fa08c86b | 2076 | } else { |
2077 | host = host_to_connect; | |
8e7895b8 | 2078 | type = SSH_CHANNEL_PORT_LISTENER; |
fa08c86b | 2079 | } |
2080 | ||
719fc62f | 2081 | if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) { |
02a024dd | 2082 | error("Forward host name too long."); |
2083 | return success; | |
2084 | } | |
5260325f | 2085 | |
fa08c86b | 2086 | /* XXX listen_address is currently ignored */ |
aa3378df | 2087 | /* |
48e671d5 | 2088 | * getaddrinfo returns a loopback address if the hostname is |
2089 | * set to NULL and hints.ai_flags is not AI_PASSIVE | |
aa3378df | 2090 | */ |
48e671d5 | 2091 | memset(&hints, 0, sizeof(hints)); |
2092 | hints.ai_family = IPv4or6; | |
2093 | hints.ai_flags = gateway_ports ? AI_PASSIVE : 0; | |
2094 | hints.ai_socktype = SOCK_STREAM; | |
fa08c86b | 2095 | snprintf(strport, sizeof strport, "%d", listen_port); |
48e671d5 | 2096 | if (getaddrinfo(NULL, strport, &hints, &aitop) != 0) |
2097 | packet_disconnect("getaddrinfo: fatal error"); | |
2098 | ||
48e671d5 | 2099 | for (ai = aitop; ai; ai = ai->ai_next) { |
2100 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2101 | continue; | |
2102 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), | |
2103 | strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
fa08c86b | 2104 | error("channel_request_forwarding: getnameinfo failed"); |
48e671d5 | 2105 | continue; |
2106 | } | |
2107 | /* Create a port to listen for the host. */ | |
2108 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
2109 | if (sock < 0) { | |
2110 | /* this is no error since kernel may not support ipv6 */ | |
2111 | verbose("socket: %.100s", strerror(errno)); | |
2112 | continue; | |
2113 | } | |
2114 | /* | |
2115 | * Set socket options. We would like the socket to disappear | |
2116 | * as soon as it has been closed for whatever reason. | |
2117 | */ | |
2118 | setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on)); | |
2119 | linger.l_onoff = 1; | |
2120 | linger.l_linger = 5; | |
2121 | setsockopt(sock, SOL_SOCKET, SO_LINGER, (void *)&linger, sizeof(linger)); | |
2122 | debug("Local forwarding listening on %s port %s.", ntop, strport); | |
2123 | ||
2124 | /* Bind the socket to the address. */ | |
2125 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
2126 | /* address can be in use ipv6 address is already bound */ | |
16218745 | 2127 | if (!ai->ai_next) |
2128 | error("bind: %.100s", strerror(errno)); | |
2129 | else | |
2130 | verbose("bind: %.100s", strerror(errno)); | |
2b87da3b | 2131 | |
48e671d5 | 2132 | close(sock); |
2133 | continue; | |
2134 | } | |
2135 | /* Start listening for connections on the socket. */ | |
2136 | if (listen(sock, 5) < 0) { | |
2137 | error("listen: %.100s", strerror(errno)); | |
2138 | close(sock); | |
2139 | continue; | |
2140 | } | |
2141 | /* Allocate a channel number for the socket. */ | |
8e7895b8 | 2142 | c = channel_new("port listener", type, sock, sock, -1, |
0b242b12 | 2143 | CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, |
a22aff1f | 2144 | 0, xstrdup("port listener"), 1); |
719fc62f | 2145 | if (c == NULL) { |
2146 | error("channel_request_forwarding: channel_new failed"); | |
2147 | close(sock); | |
2148 | continue; | |
2149 | } | |
2150 | strlcpy(c->path, host, sizeof(c->path)); | |
2151 | c->host_port = port_to_connect; | |
2152 | c->listening_port = listen_port; | |
48e671d5 | 2153 | success = 1; |
2154 | } | |
2155 | if (success == 0) | |
02a024dd | 2156 | error("channel_request_forwarding: cannot listen to port: %d", |
2157 | listen_port); | |
48e671d5 | 2158 | freeaddrinfo(aitop); |
02a024dd | 2159 | return success; |
5260325f | 2160 | } |
8efc0c15 | 2161 | |
aa3378df | 2162 | /* |
2163 | * Initiate forwarding of connections to port "port" on remote host through | |
2164 | * the secure channel to host:port from local side. | |
2165 | */ | |
8efc0c15 | 2166 | |
6ae2364d | 2167 | void |
fa08c86b | 2168 | channel_request_remote_forwarding(u_short listen_port, |
2169 | const char *host_to_connect, u_short port_to_connect) | |
8efc0c15 | 2170 | { |
fa08c86b | 2171 | int payload_len, type, success = 0; |
2172 | ||
5260325f | 2173 | /* Record locally that connection to this host/port is permitted. */ |
2174 | if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION) | |
2175 | fatal("channel_request_remote_forwarding: too many forwards"); | |
2176 | ||
5260325f | 2177 | /* Send the forward request to the remote side. */ |
7e7327a1 | 2178 | if (compat20) { |
2179 | const char *address_to_bind = "0.0.0.0"; | |
2180 | packet_start(SSH2_MSG_GLOBAL_REQUEST); | |
2181 | packet_put_cstring("tcpip-forward"); | |
2182 | packet_put_char(0); /* boolean: want reply */ | |
2183 | packet_put_cstring(address_to_bind); | |
2184 | packet_put_int(listen_port); | |
fa08c86b | 2185 | packet_send(); |
2186 | packet_write_wait(); | |
2187 | /* Assume that server accepts the request */ | |
2188 | success = 1; | |
7e7327a1 | 2189 | } else { |
2190 | packet_start(SSH_CMSG_PORT_FORWARD_REQUEST); | |
7e7327a1 | 2191 | packet_put_int(listen_port); |
d6f24e45 | 2192 | packet_put_cstring(host_to_connect); |
2193 | packet_put_int(port_to_connect); | |
7e7327a1 | 2194 | packet_send(); |
2195 | packet_write_wait(); | |
fa08c86b | 2196 | |
2197 | /* Wait for response from the remote side. */ | |
2198 | type = packet_read(&payload_len); | |
2199 | switch (type) { | |
2200 | case SSH_SMSG_SUCCESS: | |
2201 | success = 1; | |
2202 | break; | |
2203 | case SSH_SMSG_FAILURE: | |
2204 | log("Warning: Server denied remote port forwarding."); | |
2205 | break; | |
2206 | default: | |
2207 | /* Unknown packet */ | |
2208 | packet_disconnect("Protocol error for port forward request:" | |
2209 | "received packet type %d.", type); | |
2210 | } | |
2211 | } | |
2212 | if (success) { | |
2213 | permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect); | |
2214 | permitted_opens[num_permitted_opens].port_to_connect = port_to_connect; | |
2215 | permitted_opens[num_permitted_opens].listen_port = listen_port; | |
2216 | num_permitted_opens++; | |
7e7327a1 | 2217 | } |
8efc0c15 | 2218 | } |
2219 | ||
aa3378df | 2220 | /* |
2221 | * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates | |
2222 | * listening for the port, and sends back a success reply (or disconnect | |
2223 | * message if there was an error). This never returns if there was an error. | |
2224 | */ | |
8efc0c15 | 2225 | |
6ae2364d | 2226 | void |
1d1ffb87 | 2227 | channel_input_port_forward_request(int is_root, int gateway_ports) |
8efc0c15 | 2228 | { |
57112b5a | 2229 | u_short port, host_port; |
5260325f | 2230 | char *hostname; |
2231 | ||
2232 | /* Get arguments from the packet. */ | |
2233 | port = packet_get_int(); | |
2234 | hostname = packet_get_string(NULL); | |
2235 | host_port = packet_get_int(); | |
2236 | ||
3c62e7eb | 2237 | #ifndef HAVE_CYGWIN |
aa3378df | 2238 | /* |
2239 | * Check that an unprivileged user is not trying to forward a | |
2240 | * privileged port. | |
2241 | */ | |
5260325f | 2242 | if (port < IPPORT_RESERVED && !is_root) |
2243 | packet_disconnect("Requested forwarding of port %d but user is not root.", | |
2244 | port); | |
3c62e7eb | 2245 | #endif |
fa08c86b | 2246 | /* Initiate forwarding */ |
1d1ffb87 | 2247 | channel_request_local_forwarding(port, hostname, host_port, gateway_ports); |
5260325f | 2248 | |
2249 | /* Free the argument string. */ | |
2250 | xfree(hostname); | |
8efc0c15 | 2251 | } |
2252 | ||
01794848 | 2253 | /* |
2254 | * Permits opening to any host/port if permitted_opens[] is empty. This is | |
2255 | * usually called by the server, because the user could connect to any port | |
2256 | * anyway, and the server has no way to know but to trust the client anyway. | |
2257 | */ | |
2258 | void | |
2259 | channel_permit_all_opens() | |
2260 | { | |
2261 | if (num_permitted_opens == 0) | |
2262 | all_opens_permitted = 1; | |
2263 | } | |
2264 | ||
cd332296 | 2265 | void |
01794848 | 2266 | channel_add_permitted_opens(char *host, int port) |
2267 | { | |
2268 | if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION) | |
2269 | fatal("channel_request_remote_forwarding: too many forwards"); | |
2270 | debug("allow port forwarding to host %s port %d", host, port); | |
2271 | ||
2272 | permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host); | |
2273 | permitted_opens[num_permitted_opens].port_to_connect = port; | |
2274 | num_permitted_opens++; | |
2275 | ||
2276 | all_opens_permitted = 0; | |
2277 | } | |
2278 | ||
cd332296 | 2279 | void |
01794848 | 2280 | channel_clear_permitted_opens(void) |
2281 | { | |
2282 | int i; | |
2283 | ||
2284 | for (i = 0; i < num_permitted_opens; i++) | |
2285 | xfree(permitted_opens[i].host_to_connect); | |
2286 | num_permitted_opens = 0; | |
2287 | ||
2288 | } | |
2289 | ||
2290 | ||
2291 | /* return socket to remote host, port */ | |
396c147e | 2292 | static int |
01794848 | 2293 | connect_to(const char *host, u_short port) |
8efc0c15 | 2294 | { |
48e671d5 | 2295 | struct addrinfo hints, *ai, *aitop; |
2296 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; | |
2297 | int gaierr; | |
7368a6c8 | 2298 | int sock = -1; |
48e671d5 | 2299 | |
2300 | memset(&hints, 0, sizeof(hints)); | |
2301 | hints.ai_family = IPv4or6; | |
2302 | hints.ai_socktype = SOCK_STREAM; | |
01794848 | 2303 | snprintf(strport, sizeof strport, "%d", port); |
48e671d5 | 2304 | if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) { |
01794848 | 2305 | error("connect_to %.100s: unknown host (%s)", host, |
2306 | gai_strerror(gaierr)); | |
7368a6c8 | 2307 | return -1; |
48e671d5 | 2308 | } |
48e671d5 | 2309 | for (ai = aitop; ai; ai = ai->ai_next) { |
2310 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2311 | continue; | |
2312 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), | |
2313 | strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
01794848 | 2314 | error("connect_to: getnameinfo failed"); |
48e671d5 | 2315 | continue; |
5260325f | 2316 | } |
48e671d5 | 2317 | sock = socket(ai->ai_family, SOCK_STREAM, 0); |
2318 | if (sock < 0) { | |
2319 | error("socket: %.100s", strerror(errno)); | |
2320 | continue; | |
5260325f | 2321 | } |
eea39c02 | 2322 | if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0) |
97fb6912 | 2323 | fatal("connect_to: F_SETFL: %s", strerror(errno)); |
97fb6912 | 2324 | if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 && |
2325 | errno != EINPROGRESS) { | |
01794848 | 2326 | error("connect_to %.100s port %s: %.100s", ntop, strport, |
48e671d5 | 2327 | strerror(errno)); |
2328 | close(sock); | |
2b87da3b | 2329 | continue; /* fail -- try next */ |
48e671d5 | 2330 | } |
2331 | break; /* success */ | |
5260325f | 2332 | |
5260325f | 2333 | } |
48e671d5 | 2334 | freeaddrinfo(aitop); |
48e671d5 | 2335 | if (!ai) { |
01794848 | 2336 | error("connect_to %.100s port %d: failed.", host, port); |
7368a6c8 | 2337 | return -1; |
8efc0c15 | 2338 | } |
7368a6c8 | 2339 | /* success */ |
2340 | return sock; | |
2341 | } | |
01794848 | 2342 | |
fa08c86b | 2343 | int |
b3f8a79c | 2344 | channel_connect_by_listen_address(u_short listen_port) |
fa08c86b | 2345 | { |
2346 | int i; | |
01794848 | 2347 | |
fa08c86b | 2348 | for (i = 0; i < num_permitted_opens; i++) |
2349 | if (permitted_opens[i].listen_port == listen_port) | |
01794848 | 2350 | return connect_to( |
fa08c86b | 2351 | permitted_opens[i].host_to_connect, |
2352 | permitted_opens[i].port_to_connect); | |
0b6fbf03 | 2353 | error("WARNING: Server requests forwarding for unknown listen_port %d", |
2354 | listen_port); | |
fa08c86b | 2355 | return -1; |
2356 | } | |
48e671d5 | 2357 | |
01794848 | 2358 | /* Check if connecting to that port is permitted and connect. */ |
2359 | int | |
2360 | channel_connect_to(const char *host, u_short port) | |
2361 | { | |
2362 | int i, permit; | |
2363 | ||
2364 | permit = all_opens_permitted; | |
2365 | if (!permit) { | |
2366 | for (i = 0; i < num_permitted_opens; i++) | |
2367 | if (permitted_opens[i].port_to_connect == port && | |
2368 | strcmp(permitted_opens[i].host_to_connect, host) == 0) | |
2369 | permit = 1; | |
2370 | ||
2371 | } | |
2372 | if (!permit) { | |
2373 | log("Received request to connect to host %.100s port %d, " | |
2374 | "but the request was denied.", host, port); | |
2375 | return -1; | |
2376 | } | |
2377 | return connect_to(host, port); | |
2378 | } | |
2379 | ||
8e7895b8 | 2380 | /* -- X11 forwarding */ |
8efc0c15 | 2381 | |
aa3378df | 2382 | /* |
2383 | * Creates an internet domain socket for listening for X11 connections. | |
2384 | * Returns a suitable value for the DISPLAY variable, or NULL if an error | |
2385 | * occurs. | |
2386 | */ | |
5260325f | 2387 | char * |
95f1eccc | 2388 | x11_create_display_inet(int screen_number, int x11_display_offset) |
8efc0c15 | 2389 | { |
57112b5a | 2390 | int display_number, sock; |
2391 | u_short port; | |
48e671d5 | 2392 | struct addrinfo hints, *ai, *aitop; |
2393 | char strport[NI_MAXSERV]; | |
2394 | int gaierr, n, num_socks = 0, socks[NUM_SOCKS]; | |
2395 | char display[512]; | |
5260325f | 2396 | char hostname[MAXHOSTNAMELEN]; |
2397 | ||
95f1eccc | 2398 | for (display_number = x11_display_offset; |
5260325f | 2399 | display_number < MAX_DISPLAYS; |
2400 | display_number++) { | |
2401 | port = 6000 + display_number; | |
48e671d5 | 2402 | memset(&hints, 0, sizeof(hints)); |
2403 | hints.ai_family = IPv4or6; | |
2404 | hints.ai_flags = AI_PASSIVE; /* XXX loopback only ? */ | |
2405 | hints.ai_socktype = SOCK_STREAM; | |
2406 | snprintf(strport, sizeof strport, "%d", port); | |
2407 | if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) { | |
2408 | error("getaddrinfo: %.100s", gai_strerror(gaierr)); | |
5260325f | 2409 | return NULL; |
2410 | } | |
48e671d5 | 2411 | for (ai = aitop; ai; ai = ai->ai_next) { |
2412 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2413 | continue; | |
2414 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
2415 | if (sock < 0) { | |
4ee81249 | 2416 | if ((errno != EINVAL) && (errno != EAFNOSUPPORT)) { |
80a44451 | 2417 | error("socket: %.100s", strerror(errno)); |
2418 | return NULL; | |
2419 | } else { | |
22d89d24 | 2420 | debug("x11_create_display_inet: Socket family %d not supported", |
2421 | ai->ai_family); | |
80a44451 | 2422 | continue; |
2423 | } | |
48e671d5 | 2424 | } |
2425 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
2426 | debug("bind port %d: %.100s", port, strerror(errno)); | |
2427 | shutdown(sock, SHUT_RDWR); | |
2428 | close(sock); | |
16218745 | 2429 | |
2430 | if (ai->ai_next) | |
2431 | continue; | |
2432 | ||
48e671d5 | 2433 | for (n = 0; n < num_socks; n++) { |
2434 | shutdown(socks[n], SHUT_RDWR); | |
2435 | close(socks[n]); | |
2436 | } | |
2437 | num_socks = 0; | |
2438 | break; | |
2439 | } | |
2440 | socks[num_socks++] = sock; | |
80faa19f | 2441 | #ifndef DONT_TRY_OTHER_AF |
48e671d5 | 2442 | if (num_socks == NUM_SOCKS) |
2443 | break; | |
80faa19f | 2444 | #else |
2445 | break; | |
2446 | #endif | |
5260325f | 2447 | } |
4ccb01d6 | 2448 | freeaddrinfo(aitop); |
48e671d5 | 2449 | if (num_socks > 0) |
2450 | break; | |
5260325f | 2451 | } |
2452 | if (display_number >= MAX_DISPLAYS) { | |
2453 | error("Failed to allocate internet-domain X11 display socket."); | |
2454 | return NULL; | |
8efc0c15 | 2455 | } |
5260325f | 2456 | /* Start listening for connections on the socket. */ |
48e671d5 | 2457 | for (n = 0; n < num_socks; n++) { |
2458 | sock = socks[n]; | |
2459 | if (listen(sock, 5) < 0) { | |
2460 | error("listen: %.100s", strerror(errno)); | |
2461 | shutdown(sock, SHUT_RDWR); | |
2462 | close(sock); | |
2463 | return NULL; | |
2464 | } | |
8efc0c15 | 2465 | } |
48e671d5 | 2466 | |
5260325f | 2467 | /* Set up a suitable value for the DISPLAY variable. */ |
2468 | if (gethostname(hostname, sizeof(hostname)) < 0) | |
2469 | fatal("gethostname: %.100s", strerror(errno)); | |
a7effaac | 2470 | |
2471 | #ifdef IPADDR_IN_DISPLAY | |
2b87da3b | 2472 | /* |
a7effaac | 2473 | * HPUX detects the local hostname in the DISPLAY variable and tries |
2474 | * to set up a shared memory connection to the server, which it | |
2475 | * incorrectly supposes to be local. | |
2476 | * | |
2477 | * The workaround - as used in later $$H and other programs - is | |
2478 | * is to set display to the host's IP address. | |
2479 | */ | |
2480 | { | |
2481 | struct hostent *he; | |
2482 | struct in_addr my_addr; | |
2483 | ||
2484 | he = gethostbyname(hostname); | |
2485 | if (he == NULL) { | |
2486 | error("[X11-broken-fwd-hostname-workaround] Could not get " | |
2487 | "IP address for hostname %s.", hostname); | |
2488 | ||
2489 | packet_send_debug("[X11-broken-fwd-hostname-workaround]" | |
2490 | "Could not get IP address for hostname %s.", hostname); | |
2491 | ||
2492 | shutdown(sock, SHUT_RDWR); | |
2493 | close(sock); | |
2494 | ||
2495 | return NULL; | |
2496 | } | |
2497 | ||
2498 | memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr)); | |
2499 | ||
2500 | /* Set DISPLAY to <ip address>:screen.display */ | |
2b87da3b | 2501 | snprintf(display, sizeof(display), "%.50s:%d.%d", inet_ntoa(my_addr), |
74141647 | 2502 | display_number, screen_number); |
a7effaac | 2503 | } |
2504 | #else /* IPADDR_IN_DISPLAY */ | |
2505 | /* Just set DISPLAY to hostname:screen.display */ | |
48e671d5 | 2506 | snprintf(display, sizeof display, "%.400s:%d.%d", hostname, |
74141647 | 2507 | display_number, screen_number); |
a7effaac | 2508 | #endif /* IPADDR_IN_DISPLAY */ |
5260325f | 2509 | |
48e671d5 | 2510 | /* Allocate a channel for each socket. */ |
2511 | for (n = 0; n < num_socks; n++) { | |
2512 | sock = socks[n]; | |
0b242b12 | 2513 | (void) channel_new("x11 listener", |
2514 | SSH_CHANNEL_X11_LISTENER, sock, sock, -1, | |
2515 | CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, | |
a22aff1f | 2516 | 0, xstrdup("X11 inet listener"), 1); |
48e671d5 | 2517 | } |
5260325f | 2518 | |
2519 | /* Return a suitable value for the DISPLAY environment variable. */ | |
48e671d5 | 2520 | return xstrdup(display); |
8efc0c15 | 2521 | } |
2522 | ||
2523 | #ifndef X_UNIX_PATH | |
2524 | #define X_UNIX_PATH "/tmp/.X11-unix/X" | |
2525 | #endif | |
2526 | ||
396c147e | 2527 | static int |
1e3b8b07 | 2528 | connect_local_xsocket(u_int dnr) |
8efc0c15 | 2529 | { |
5260325f | 2530 | static const char *const x_sockets[] = { |
2531 | X_UNIX_PATH "%u", | |
2532 | "/var/X/.X11-unix/X" "%u", | |
2533 | "/usr/spool/sockets/X11/" "%u", | |
2534 | NULL | |
2535 | }; | |
2536 | int sock; | |
2537 | struct sockaddr_un addr; | |
2538 | const char *const * path; | |
2539 | ||
2540 | for (path = x_sockets; *path; ++path) { | |
2541 | sock = socket(AF_UNIX, SOCK_STREAM, 0); | |
2542 | if (sock < 0) | |
2543 | error("socket: %.100s", strerror(errno)); | |
2544 | memset(&addr, 0, sizeof(addr)); | |
2545 | addr.sun_family = AF_UNIX; | |
2546 | snprintf(addr.sun_path, sizeof addr.sun_path, *path, dnr); | |
2547 | if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0) | |
2548 | return sock; | |
2549 | close(sock); | |
2550 | } | |
2551 | error("connect %.100s: %.100s", addr.sun_path, strerror(errno)); | |
2552 | return -1; | |
8efc0c15 | 2553 | } |
2554 | ||
0b242b12 | 2555 | int |
2556 | x11_connect_display(void) | |
8efc0c15 | 2557 | { |
0b242b12 | 2558 | int display_number, sock = 0; |
5260325f | 2559 | const char *display; |
0b242b12 | 2560 | char buf[1024], *cp; |
48e671d5 | 2561 | struct addrinfo hints, *ai, *aitop; |
2562 | char strport[NI_MAXSERV]; | |
2563 | int gaierr; | |
5260325f | 2564 | |
5260325f | 2565 | /* Try to open a socket for the local X server. */ |
2566 | display = getenv("DISPLAY"); | |
2567 | if (!display) { | |
2568 | error("DISPLAY not set."); | |
0b242b12 | 2569 | return -1; |
5260325f | 2570 | } |
aa3378df | 2571 | /* |
2572 | * Now we decode the value of the DISPLAY variable and make a | |
2573 | * connection to the real X server. | |
2574 | */ | |
2575 | ||
2576 | /* | |
2577 | * Check if it is a unix domain socket. Unix domain displays are in | |
2578 | * one of the following formats: unix:d[.s], :d[.s], ::d[.s] | |
2579 | */ | |
5260325f | 2580 | if (strncmp(display, "unix:", 5) == 0 || |
2581 | display[0] == ':') { | |
2582 | /* Connect to the unix domain socket. */ | |
2583 | if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) { | |
2584 | error("Could not parse display number from DISPLAY: %.100s", | |
2585 | display); | |
0b242b12 | 2586 | return -1; |
5260325f | 2587 | } |
2588 | /* Create a socket. */ | |
2589 | sock = connect_local_xsocket(display_number); | |
2590 | if (sock < 0) | |
0b242b12 | 2591 | return -1; |
5260325f | 2592 | |
2593 | /* OK, we now have a connection to the display. */ | |
0b242b12 | 2594 | return sock; |
5260325f | 2595 | } |
aa3378df | 2596 | /* |
2597 | * Connect to an inet socket. The DISPLAY value is supposedly | |
2598 | * hostname:d[.s], where hostname may also be numeric IP address. | |
2599 | */ | |
5260325f | 2600 | strncpy(buf, display, sizeof(buf)); |
2601 | buf[sizeof(buf) - 1] = 0; | |
2602 | cp = strchr(buf, ':'); | |
2603 | if (!cp) { | |
2604 | error("Could not find ':' in DISPLAY: %.100s", display); | |
0b242b12 | 2605 | return -1; |
5260325f | 2606 | } |
2607 | *cp = 0; | |
aa3378df | 2608 | /* buf now contains the host name. But first we parse the display number. */ |
5260325f | 2609 | if (sscanf(cp + 1, "%d", &display_number) != 1) { |
2610 | error("Could not parse display number from DISPLAY: %.100s", | |
2611 | display); | |
0b242b12 | 2612 | return -1; |
5260325f | 2613 | } |
5260325f | 2614 | |
48e671d5 | 2615 | /* Look up the host address */ |
2616 | memset(&hints, 0, sizeof(hints)); | |
2617 | hints.ai_family = IPv4or6; | |
2618 | hints.ai_socktype = SOCK_STREAM; | |
2619 | snprintf(strport, sizeof strport, "%d", 6000 + display_number); | |
2620 | if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) { | |
2621 | error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr)); | |
0b242b12 | 2622 | return -1; |
8efc0c15 | 2623 | } |
48e671d5 | 2624 | for (ai = aitop; ai; ai = ai->ai_next) { |
2625 | /* Create a socket. */ | |
2626 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
2627 | if (sock < 0) { | |
2628 | debug("socket: %.100s", strerror(errno)); | |
7368a6c8 | 2629 | continue; |
2630 | } | |
2631 | /* Connect it to the display. */ | |
2632 | if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
2633 | debug("connect %.100s port %d: %.100s", buf, | |
2634 | 6000 + display_number, strerror(errno)); | |
2635 | close(sock); | |
2636 | continue; | |
2637 | } | |
2638 | /* Success */ | |
2639 | break; | |
48e671d5 | 2640 | } |
48e671d5 | 2641 | freeaddrinfo(aitop); |
2642 | if (!ai) { | |
6ae2364d | 2643 | error("connect %.100s port %d: %.100s", buf, 6000 + display_number, |
48e671d5 | 2644 | strerror(errno)); |
0b242b12 | 2645 | return -1; |
8efc0c15 | 2646 | } |
0b242b12 | 2647 | return sock; |
2648 | } | |
5260325f | 2649 | |
0b242b12 | 2650 | /* |
2651 | * This is called when SSH_SMSG_X11_OPEN is received. The packet contains | |
2652 | * the remote channel number. We should do whatever we want, and respond | |
2653 | * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE. | |
2654 | */ | |
5260325f | 2655 | |
0b242b12 | 2656 | void |
188adeb2 | 2657 | x11_input_open(int type, int plen, void *ctxt) |
0b242b12 | 2658 | { |
719fc62f | 2659 | Channel *c = NULL; |
2660 | int remote_id, sock = 0; | |
0b242b12 | 2661 | char *remote_host; |
5260325f | 2662 | |
719fc62f | 2663 | debug("Received X11 open request."); |
5260325f | 2664 | |
719fc62f | 2665 | remote_id = packet_get_int(); |
8e7895b8 | 2666 | |
2667 | if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) { | |
719fc62f | 2668 | remote_host = packet_get_string(NULL); |
0b242b12 | 2669 | } else { |
2670 | remote_host = xstrdup("unknown (remote did not supply name)"); | |
0b242b12 | 2671 | } |
719fc62f | 2672 | packet_done(); |
0b242b12 | 2673 | |
2674 | /* Obtain a connection to the real X display. */ | |
2675 | sock = x11_connect_display(); | |
719fc62f | 2676 | if (sock != -1) { |
2677 | /* Allocate a channel for this connection. */ | |
2678 | c = channel_new("connected x11 socket", | |
2679 | SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0, | |
2680 | remote_host, 1); | |
2681 | if (c == NULL) { | |
2682 | error("x11_input_open: channel_new failed"); | |
2683 | close(sock); | |
2684 | } else { | |
2685 | c->remote_id = remote_id; | |
a5f82435 | 2686 | c->force_drain = 1; |
719fc62f | 2687 | } |
2688 | } | |
2689 | if (c == NULL) { | |
0b242b12 | 2690 | /* Send refusal to the remote host. */ |
2691 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
719fc62f | 2692 | packet_put_int(remote_id); |
0b242b12 | 2693 | } else { |
0b242b12 | 2694 | /* Send a confirmation to the remote host. */ |
2695 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
719fc62f | 2696 | packet_put_int(remote_id); |
2697 | packet_put_int(c->self); | |
0b242b12 | 2698 | } |
719fc62f | 2699 | packet_send(); |
8efc0c15 | 2700 | } |
2701 | ||
a22aff1f | 2702 | /* dummy protocol handler that denies SSH-1 requests (agent/x11) */ |
2703 | void | |
2704 | deny_input_open(int type, int plen, void *ctxt) | |
2705 | { | |
2706 | int rchan = packet_get_int(); | |
2707 | switch(type){ | |
2708 | case SSH_SMSG_AGENT_OPEN: | |
2709 | error("Warning: ssh server tried agent forwarding."); | |
2710 | break; | |
2711 | case SSH_SMSG_X11_OPEN: | |
2712 | error("Warning: ssh server tried X11 forwarding."); | |
2713 | break; | |
2714 | default: | |
2715 | error("deny_input_open: type %d plen %d", type, plen); | |
2716 | break; | |
2717 | } | |
2718 | error("Warning: this is probably a break in attempt by a malicious server."); | |
2719 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
2720 | packet_put_int(rchan); | |
2721 | packet_send(); | |
2722 | } | |
2723 | ||
aa3378df | 2724 | /* |
2725 | * Requests forwarding of X11 connections, generates fake authentication | |
2726 | * data, and enables authentication spoofing. | |
8e7895b8 | 2727 | * This should be called in the client only. |
aa3378df | 2728 | */ |
6ae2364d | 2729 | void |
0b242b12 | 2730 | x11_request_forwarding_with_spoofing(int client_session_id, |
2731 | const char *proto, const char *data) | |
8efc0c15 | 2732 | { |
1e3b8b07 | 2733 | u_int data_len = (u_int) strlen(data) / 2; |
ca910e13 | 2734 | u_int i, value, len; |
5260325f | 2735 | char *new_data; |
2736 | int screen_number; | |
2737 | const char *cp; | |
2738 | u_int32_t rand = 0; | |
2739 | ||
2740 | cp = getenv("DISPLAY"); | |
2741 | if (cp) | |
2742 | cp = strchr(cp, ':'); | |
2743 | if (cp) | |
2744 | cp = strchr(cp, '.'); | |
2745 | if (cp) | |
2746 | screen_number = atoi(cp + 1); | |
2747 | else | |
2748 | screen_number = 0; | |
2749 | ||
2750 | /* Save protocol name. */ | |
2751 | x11_saved_proto = xstrdup(proto); | |
2752 | ||
aa3378df | 2753 | /* |
2754 | * Extract real authentication data and generate fake data of the | |
2755 | * same length. | |
2756 | */ | |
5260325f | 2757 | x11_saved_data = xmalloc(data_len); |
2758 | x11_fake_data = xmalloc(data_len); | |
2759 | for (i = 0; i < data_len; i++) { | |
2760 | if (sscanf(data + 2 * i, "%2x", &value) != 1) | |
2761 | fatal("x11_request_forwarding: bad authentication data: %.100s", data); | |
2762 | if (i % 4 == 0) | |
2763 | rand = arc4random(); | |
2764 | x11_saved_data[i] = value; | |
2765 | x11_fake_data[i] = rand & 0xff; | |
2766 | rand >>= 8; | |
2767 | } | |
2768 | x11_saved_data_len = data_len; | |
2769 | x11_fake_data_len = data_len; | |
2770 | ||
2771 | /* Convert the fake data into hex. */ | |
ca910e13 | 2772 | len = 2 * data_len + 1; |
2773 | new_data = xmalloc(len); | |
5260325f | 2774 | for (i = 0; i < data_len; i++) |
ca910e13 | 2775 | snprintf(new_data + 2 * i, len - 2 * i, |
2776 | "%02x", (u_char) x11_fake_data[i]); | |
5260325f | 2777 | |
2778 | /* Send the request packet. */ | |
0b242b12 | 2779 | if (compat20) { |
2780 | channel_request_start(client_session_id, "x11-req", 0); | |
2781 | packet_put_char(0); /* XXX bool single connection */ | |
2782 | } else { | |
2783 | packet_start(SSH_CMSG_X11_REQUEST_FORWARDING); | |
2784 | } | |
2785 | packet_put_cstring(proto); | |
2786 | packet_put_cstring(new_data); | |
5260325f | 2787 | packet_put_int(screen_number); |
2788 | packet_send(); | |
2789 | packet_write_wait(); | |
2790 | xfree(new_data); | |
8efc0c15 | 2791 | } |
2792 | ||
8e7895b8 | 2793 | |
2794 | /* -- agent forwarding */ | |
2795 | ||
8efc0c15 | 2796 | /* Sends a message to the server to request authentication fd forwarding. */ |
2797 | ||
6ae2364d | 2798 | void |
5260325f | 2799 | auth_request_forwarding() |
8efc0c15 | 2800 | { |
5260325f | 2801 | packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING); |
2802 | packet_send(); | |
2803 | packet_write_wait(); | |
8efc0c15 | 2804 | } |
2805 | ||
aa3378df | 2806 | /* |
2807 | * Returns the name of the forwarded authentication socket. Returns NULL if | |
2808 | * there is no forwarded authentication socket. The returned value points to | |
2809 | * a static buffer. | |
2810 | */ | |
8efc0c15 | 2811 | |
5260325f | 2812 | char * |
2813 | auth_get_socket_name() | |
8efc0c15 | 2814 | { |
8e7895b8 | 2815 | return auth_sock_name; |
8efc0c15 | 2816 | } |
2817 | ||
2818 | /* removes the agent forwarding socket */ | |
2819 | ||
6ae2364d | 2820 | void |
f0f32b8e | 2821 | auth_sock_cleanup_proc(void *_pw) |
5260325f | 2822 | { |
f0f32b8e | 2823 | struct passwd *pw = _pw; |
2824 | ||
e4f7282d | 2825 | if (auth_sock_name) { |
f0f32b8e | 2826 | temporarily_use_uid(pw); |
e4f7282d | 2827 | unlink(auth_sock_name); |
2828 | rmdir(auth_sock_dir); | |
2829 | auth_sock_name = NULL; | |
f0f32b8e | 2830 | restore_uid(); |
e4f7282d | 2831 | } |
8efc0c15 | 2832 | } |
2833 | ||
aa3378df | 2834 | /* |
fa649821 | 2835 | * This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server. |
aa3378df | 2836 | * This starts forwarding authentication requests. |
2837 | */ | |
8efc0c15 | 2838 | |
fa649821 | 2839 | int |
5260325f | 2840 | auth_input_request_forwarding(struct passwd * pw) |
8efc0c15 | 2841 | { |
719fc62f | 2842 | Channel *nc; |
2843 | int sock; | |
5260325f | 2844 | struct sockaddr_un sunaddr; |
2845 | ||
8e7895b8 | 2846 | if (auth_get_socket_name() != NULL) { |
2847 | error("authentication forwarding requested twice."); | |
2848 | return 0; | |
2849 | } | |
5260325f | 2850 | |
2851 | /* Temporarily drop privileged uid for mkdir/bind. */ | |
63bd8c36 | 2852 | temporarily_use_uid(pw); |
5260325f | 2853 | |
2854 | /* Allocate a buffer for the socket name, and format the name. */ | |
8e7895b8 | 2855 | auth_sock_name = xmalloc(MAXPATHLEN); |
2856 | auth_sock_dir = xmalloc(MAXPATHLEN); | |
2857 | strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXX", MAXPATHLEN); | |
5260325f | 2858 | |
2859 | /* Create private directory for socket */ | |
8e7895b8 | 2860 | if (mkdtemp(auth_sock_dir) == NULL) { |
2861 | packet_send_debug("Agent forwarding disabled: " | |
2862 | "mkdtemp() failed: %.100s", strerror(errno)); | |
fa649821 | 2863 | restore_uid(); |
8e7895b8 | 2864 | xfree(auth_sock_name); |
2865 | xfree(auth_sock_dir); | |
2866 | auth_sock_name = NULL; | |
2867 | auth_sock_dir = NULL; | |
fa649821 | 2868 | return 0; |
2869 | } | |
8e7895b8 | 2870 | snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%d", |
2871 | auth_sock_dir, (int) getpid()); | |
5260325f | 2872 | |
e4f7282d | 2873 | /* delete agent socket on fatal() */ |
f0f32b8e | 2874 | fatal_add_cleanup(auth_sock_cleanup_proc, pw); |
e4f7282d | 2875 | |
5260325f | 2876 | /* Create the socket. */ |
2877 | sock = socket(AF_UNIX, SOCK_STREAM, 0); | |
2878 | if (sock < 0) | |
2879 | packet_disconnect("socket: %.100s", strerror(errno)); | |
2880 | ||
2881 | /* Bind it to the name. */ | |
2882 | memset(&sunaddr, 0, sizeof(sunaddr)); | |
2883 | sunaddr.sun_family = AF_UNIX; | |
8e7895b8 | 2884 | strncpy(sunaddr.sun_path, auth_sock_name, |
5260325f | 2885 | sizeof(sunaddr.sun_path)); |
2886 | ||
2887 | if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) | |
2888 | packet_disconnect("bind: %.100s", strerror(errno)); | |
2889 | ||
2890 | /* Restore the privileged uid. */ | |
2891 | restore_uid(); | |
2892 | ||
2893 | /* Start listening on the socket. */ | |
2894 | if (listen(sock, 5) < 0) | |
2895 | packet_disconnect("listen: %.100s", strerror(errno)); | |
2896 | ||
2897 | /* Allocate a channel for the authentication agent socket. */ | |
719fc62f | 2898 | nc = channel_new("auth socket", |
fa08c86b | 2899 | SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1, |
2900 | CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, | |
2901 | 0, xstrdup("auth socket"), 1); | |
719fc62f | 2902 | if (nc == NULL) { |
2903 | error("auth_input_request_forwarding: channel_new failed"); | |
f0f32b8e | 2904 | auth_sock_cleanup_proc(pw); |
750c256a | 2905 | fatal_remove_cleanup(auth_sock_cleanup_proc, pw); |
719fc62f | 2906 | close(sock); |
2907 | return 0; | |
2908 | } | |
8e7895b8 | 2909 | strlcpy(nc->path, auth_sock_name, sizeof(nc->path)); |
fa649821 | 2910 | return 1; |
8efc0c15 | 2911 | } |
2912 | ||
2913 | /* This is called to process an SSH_SMSG_AGENT_OPEN message. */ | |
2914 | ||
6ae2364d | 2915 | void |
188adeb2 | 2916 | auth_input_open_request(int type, int plen, void *ctxt) |
8efc0c15 | 2917 | { |
719fc62f | 2918 | Channel *c = NULL; |
2919 | int remote_id, sock; | |
8e7895b8 | 2920 | char *name; |
5260325f | 2921 | |
7368a6c8 | 2922 | packet_integrity_check(plen, 4, type); |
2923 | ||
5260325f | 2924 | /* Read the remote channel number from the message. */ |
719fc62f | 2925 | remote_id = packet_get_int(); |
5260325f | 2926 | |
aa3378df | 2927 | /* |
2928 | * Get a connection to the local authentication agent (this may again | |
2929 | * get forwarded). | |
2930 | */ | |
5260325f | 2931 | sock = ssh_get_authentication_socket(); |
2932 | ||
aa3378df | 2933 | /* |
2934 | * If we could not connect the agent, send an error message back to | |
2935 | * the server. This should never happen unless the agent dies, | |
2936 | * because authentication forwarding is only enabled if we have an | |
2937 | * agent. | |
2938 | */ | |
719fc62f | 2939 | if (sock >= 0) { |
8e7895b8 | 2940 | name = xstrdup("authentication agent connection"); |
2941 | c = channel_new("", SSH_CHANNEL_OPEN, sock, sock, | |
2942 | -1, 0, 0, 0, name, 1); | |
719fc62f | 2943 | if (c == NULL) { |
2944 | error("auth_input_open_request: channel_new failed"); | |
8e7895b8 | 2945 | xfree(name); |
719fc62f | 2946 | close(sock); |
2947 | } else { | |
2948 | c->remote_id = remote_id; | |
a5f82435 | 2949 | c->force_drain = 1; |
719fc62f | 2950 | } |
2951 | } | |
2952 | if (c == NULL) { | |
5260325f | 2953 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); |
719fc62f | 2954 | packet_put_int(remote_id); |
2955 | } else { | |
2956 | /* Send a confirmation to the remote host. */ | |
2957 | debug("Forwarding authentication connection."); | |
2958 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
2959 | packet_put_int(remote_id); | |
2960 | packet_put_int(c->self); | |
5260325f | 2961 | } |
5260325f | 2962 | packet_send(); |
8efc0c15 | 2963 | } |