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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" | |
489aa2e9 | 42 | RCSID("$OpenBSD: channels.c,v 1.132 2001/07/17 21:04:56 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; | |
3cf2be58 | 263 | c->detach_user = NULL; |
2e73a022 | 264 | c->input_filter = NULL; |
5260325f | 265 | debug("channel %d: new [%s]", found, remote_name); |
719fc62f | 266 | return c; |
7368a6c8 | 267 | } |
8efc0c15 | 268 | |
489aa2e9 | 269 | static int |
270 | channel_find_maxfd(void) | |
271 | { | |
272 | int i, max = 0; | |
273 | Channel *c; | |
274 | ||
275 | for (i = 0; i < channels_alloc; i++) { | |
276 | c = channels[i]; | |
277 | if (c != NULL) { | |
278 | max = MAX(max, c->rfd); | |
279 | max = MAX(max, c->wfd); | |
280 | max = MAX(max, c->efd); | |
281 | } | |
282 | } | |
283 | return max; | |
284 | } | |
285 | ||
286 | int | |
287 | channel_close_fd(int *fdp) | |
288 | { | |
289 | int ret = 0, fd = *fdp; | |
290 | ||
291 | if (fd != -1) { | |
292 | ret = close(fd); | |
293 | *fdp = -1; | |
294 | if (fd == channel_max_fd) | |
295 | channel_max_fd = channel_find_maxfd(); | |
296 | } | |
297 | return ret; | |
298 | } | |
299 | ||
0fbe8c74 | 300 | /* Close all channel fd/socket. */ |
301 | ||
396c147e | 302 | static void |
0fbe8c74 | 303 | channel_close_fds(Channel *c) |
304 | { | |
6fd8622b | 305 | debug3("channel_close_fds: channel %d: r %d w %d e %d", |
306 | c->self, c->rfd, c->wfd, c->efd); | |
307 | ||
489aa2e9 | 308 | channel_close_fd(&c->sock); |
309 | channel_close_fd(&c->rfd); | |
310 | channel_close_fd(&c->wfd); | |
311 | channel_close_fd(&c->efd); | |
0fbe8c74 | 312 | } |
313 | ||
8e7895b8 | 314 | /* Free the channel and close its fd/socket. */ |
315 | ||
316 | void | |
317 | channel_free(Channel *c) | |
318 | { | |
319 | char *s; | |
320 | int i, n; | |
321 | ||
322 | for (n = 0, i = 0; i < channels_alloc; i++) | |
323 | if (channels[i]) | |
324 | n++; | |
325 | debug("channel_free: channel %d: %s, nchannels %d", c->self, | |
326 | c->remote_name ? c->remote_name : "???", n); | |
327 | ||
328 | s = channel_open_message(); | |
329 | debug3("channel_free: status: %s", s); | |
330 | xfree(s); | |
331 | ||
3cf2be58 | 332 | if (c->detach_user != NULL) { |
333 | debug("channel_free: channel %d: detaching channel user", c->self); | |
334 | c->detach_user(c->self, NULL); | |
8e7895b8 | 335 | } |
336 | if (c->sock != -1) | |
337 | shutdown(c->sock, SHUT_RDWR); | |
338 | channel_close_fds(c); | |
339 | buffer_free(&c->input); | |
340 | buffer_free(&c->output); | |
341 | buffer_free(&c->extended); | |
342 | if (c->remote_name) { | |
343 | xfree(c->remote_name); | |
344 | c->remote_name = NULL; | |
345 | } | |
346 | channels[c->self] = NULL; | |
347 | xfree(c); | |
348 | } | |
349 | ||
8e7895b8 | 350 | void |
d6746a0b | 351 | channel_free_all(void) |
8e7895b8 | 352 | { |
353 | int i; | |
8e7895b8 | 354 | |
d6746a0b | 355 | for (i = 0; i < channels_alloc; i++) |
356 | if (channels[i] != NULL) | |
357 | channel_free(channels[i]); | |
8e7895b8 | 358 | } |
359 | ||
3cf2be58 | 360 | void |
361 | channel_detach_all(void) | |
362 | { | |
363 | int i; | |
364 | Channel *c; | |
365 | ||
366 | for (i = 0; i < channels_alloc; i++) { | |
367 | c = channels[i]; | |
368 | if (c != NULL && c->detach_user != NULL) { | |
369 | debug("channel_detach_all: channel %d", c->self); | |
370 | c->detach_user(c->self, NULL); | |
371 | c->detach_user = NULL; | |
372 | } | |
373 | } | |
374 | } | |
375 | ||
8e7895b8 | 376 | /* |
377 | * Closes the sockets/fds of all channels. This is used to close extra file | |
378 | * descriptors after a fork. | |
379 | */ | |
380 | ||
381 | void | |
382 | channel_close_all() | |
383 | { | |
384 | int i; | |
385 | ||
386 | for (i = 0; i < channels_alloc; i++) | |
387 | if (channels[i] != NULL) | |
388 | channel_close_fds(channels[i]); | |
389 | } | |
390 | ||
3cf2be58 | 391 | /* |
392 | * Stop listening to channels. | |
393 | */ | |
394 | ||
395 | void | |
396 | channel_stop_listening(void) | |
397 | { | |
398 | int i; | |
399 | Channel *c; | |
400 | ||
401 | for (i = 0; i < channels_alloc; i++) { | |
402 | c = channels[i]; | |
403 | if (c != NULL) { | |
404 | switch (c->type) { | |
405 | case SSH_CHANNEL_AUTH_SOCKET: | |
406 | case SSH_CHANNEL_PORT_LISTENER: | |
407 | case SSH_CHANNEL_RPORT_LISTENER: | |
408 | case SSH_CHANNEL_X11_LISTENER: | |
489aa2e9 | 409 | channel_close_fd(&c->sock); |
3cf2be58 | 410 | channel_free(c); |
411 | break; | |
412 | } | |
413 | } | |
414 | } | |
415 | } | |
416 | ||
8e7895b8 | 417 | /* |
418 | * Returns true if no channel has too much buffered data, and false if one or | |
419 | * more channel is overfull. | |
420 | */ | |
421 | ||
422 | int | |
423 | channel_not_very_much_buffered_data() | |
424 | { | |
425 | u_int i; | |
426 | Channel *c; | |
427 | ||
428 | for (i = 0; i < channels_alloc; i++) { | |
429 | c = channels[i]; | |
430 | if (c != NULL && c->type == SSH_CHANNEL_OPEN) { | |
431 | if (!compat20 && buffer_len(&c->input) > packet_get_maxsize()) { | |
432 | debug("channel %d: big input buffer %d", | |
433 | c->self, buffer_len(&c->input)); | |
434 | return 0; | |
435 | } | |
436 | if (buffer_len(&c->output) > packet_get_maxsize()) { | |
437 | debug("channel %d: big output buffer %d", | |
438 | c->self, buffer_len(&c->output)); | |
439 | return 0; | |
440 | } | |
441 | } | |
442 | } | |
443 | return 1; | |
444 | } | |
445 | ||
446 | /* Returns true if any channel is still open. */ | |
447 | ||
448 | int | |
449 | channel_still_open() | |
450 | { | |
451 | int i; | |
452 | Channel *c; | |
453 | ||
454 | for (i = 0; i < channels_alloc; i++) { | |
455 | c = channels[i]; | |
456 | if (c == NULL) | |
457 | continue; | |
458 | switch (c->type) { | |
459 | case SSH_CHANNEL_X11_LISTENER: | |
460 | case SSH_CHANNEL_PORT_LISTENER: | |
461 | case SSH_CHANNEL_RPORT_LISTENER: | |
462 | case SSH_CHANNEL_CLOSED: | |
463 | case SSH_CHANNEL_AUTH_SOCKET: | |
464 | case SSH_CHANNEL_DYNAMIC: | |
465 | case SSH_CHANNEL_CONNECTING: | |
466 | case SSH_CHANNEL_ZOMBIE: | |
467 | continue; | |
468 | case SSH_CHANNEL_LARVAL: | |
469 | if (!compat20) | |
470 | fatal("cannot happen: SSH_CHANNEL_LARVAL"); | |
471 | continue; | |
472 | case SSH_CHANNEL_OPENING: | |
473 | case SSH_CHANNEL_OPEN: | |
474 | case SSH_CHANNEL_X11_OPEN: | |
475 | return 1; | |
476 | case SSH_CHANNEL_INPUT_DRAINING: | |
477 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
478 | if (!compat13) | |
479 | fatal("cannot happen: OUT_DRAIN"); | |
480 | return 1; | |
481 | default: | |
482 | fatal("channel_still_open: bad channel type %d", c->type); | |
483 | /* NOTREACHED */ | |
484 | } | |
485 | } | |
486 | return 0; | |
487 | } | |
488 | ||
489 | /* Returns the id of an open channel suitable for keepaliving */ | |
490 | ||
491 | int | |
492 | channel_find_open() | |
493 | { | |
494 | int i; | |
495 | Channel *c; | |
496 | ||
497 | for (i = 0; i < channels_alloc; i++) { | |
498 | c = channels[i]; | |
499 | if (c == NULL) | |
500 | continue; | |
501 | switch (c->type) { | |
502 | case SSH_CHANNEL_CLOSED: | |
503 | case SSH_CHANNEL_DYNAMIC: | |
504 | case SSH_CHANNEL_X11_LISTENER: | |
505 | case SSH_CHANNEL_PORT_LISTENER: | |
506 | case SSH_CHANNEL_RPORT_LISTENER: | |
507 | case SSH_CHANNEL_OPENING: | |
508 | case SSH_CHANNEL_CONNECTING: | |
509 | case SSH_CHANNEL_ZOMBIE: | |
510 | continue; | |
511 | case SSH_CHANNEL_LARVAL: | |
512 | case SSH_CHANNEL_AUTH_SOCKET: | |
513 | case SSH_CHANNEL_OPEN: | |
514 | case SSH_CHANNEL_X11_OPEN: | |
515 | return i; | |
516 | case SSH_CHANNEL_INPUT_DRAINING: | |
517 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
518 | if (!compat13) | |
519 | fatal("cannot happen: OUT_DRAIN"); | |
520 | return i; | |
521 | default: | |
522 | fatal("channel_find_open: bad channel type %d", c->type); | |
523 | /* NOTREACHED */ | |
524 | } | |
525 | } | |
526 | return -1; | |
527 | } | |
528 | ||
529 | ||
530 | /* | |
531 | * Returns a message describing the currently open forwarded connections, | |
532 | * suitable for sending to the client. The message contains crlf pairs for | |
533 | * newlines. | |
534 | */ | |
535 | ||
536 | char * | |
537 | channel_open_message() | |
538 | { | |
539 | Buffer buffer; | |
540 | Channel *c; | |
541 | char buf[1024], *cp; | |
542 | int i; | |
543 | ||
544 | buffer_init(&buffer); | |
545 | snprintf(buf, sizeof buf, "The following connections are open:\r\n"); | |
546 | buffer_append(&buffer, buf, strlen(buf)); | |
547 | for (i = 0; i < channels_alloc; i++) { | |
548 | c = channels[i]; | |
549 | if (c == NULL) | |
550 | continue; | |
551 | switch (c->type) { | |
552 | case SSH_CHANNEL_X11_LISTENER: | |
553 | case SSH_CHANNEL_PORT_LISTENER: | |
554 | case SSH_CHANNEL_RPORT_LISTENER: | |
555 | case SSH_CHANNEL_CLOSED: | |
556 | case SSH_CHANNEL_AUTH_SOCKET: | |
557 | case SSH_CHANNEL_ZOMBIE: | |
558 | continue; | |
559 | case SSH_CHANNEL_LARVAL: | |
560 | case SSH_CHANNEL_OPENING: | |
561 | case SSH_CHANNEL_CONNECTING: | |
562 | case SSH_CHANNEL_DYNAMIC: | |
563 | case SSH_CHANNEL_OPEN: | |
564 | case SSH_CHANNEL_X11_OPEN: | |
565 | case SSH_CHANNEL_INPUT_DRAINING: | |
566 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
567 | snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n", | |
568 | c->self, c->remote_name, | |
569 | c->type, c->remote_id, | |
570 | c->istate, buffer_len(&c->input), | |
571 | c->ostate, buffer_len(&c->output), | |
572 | c->rfd, c->wfd); | |
573 | buffer_append(&buffer, buf, strlen(buf)); | |
574 | continue; | |
575 | default: | |
576 | fatal("channel_open_message: bad channel type %d", c->type); | |
577 | /* NOTREACHED */ | |
578 | } | |
579 | } | |
580 | buffer_append(&buffer, "\0", 1); | |
581 | cp = xstrdup(buffer_ptr(&buffer)); | |
582 | buffer_free(&buffer); | |
583 | return cp; | |
584 | } | |
585 | ||
586 | void | |
587 | channel_send_open(int id) | |
588 | { | |
589 | Channel *c = channel_lookup(id); | |
590 | if (c == NULL) { | |
591 | log("channel_send_open: %d: bad id", id); | |
592 | return; | |
593 | } | |
594 | debug("send channel open %d", id); | |
595 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
596 | packet_put_cstring(c->ctype); | |
597 | packet_put_int(c->self); | |
598 | packet_put_int(c->local_window); | |
599 | packet_put_int(c->local_maxpacket); | |
600 | packet_send(); | |
601 | } | |
602 | ||
603 | void | |
604 | channel_request(int id, char *service, int wantconfirm) | |
605 | { | |
606 | channel_request_start(id, service, wantconfirm); | |
607 | packet_send(); | |
608 | debug("channel request %d: %s", id, service) ; | |
609 | } | |
610 | void | |
611 | channel_request_start(int id, char *service, int wantconfirm) | |
612 | { | |
613 | Channel *c = channel_lookup(id); | |
614 | if (c == NULL) { | |
615 | log("channel_request: %d: bad id", id); | |
616 | return; | |
617 | } | |
618 | packet_start(SSH2_MSG_CHANNEL_REQUEST); | |
619 | packet_put_int(c->remote_id); | |
620 | packet_put_cstring(service); | |
621 | packet_put_char(wantconfirm); | |
622 | } | |
623 | void | |
624 | channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg) | |
625 | { | |
626 | Channel *c = channel_lookup(id); | |
627 | if (c == NULL) { | |
628 | log("channel_register_callback: %d: bad id", id); | |
629 | return; | |
630 | } | |
631 | c->cb_event = mtype; | |
632 | c->cb_fn = fn; | |
633 | c->cb_arg = arg; | |
634 | } | |
635 | void | |
636 | channel_register_cleanup(int id, channel_callback_fn *fn) | |
637 | { | |
638 | Channel *c = channel_lookup(id); | |
639 | if (c == NULL) { | |
640 | log("channel_register_cleanup: %d: bad id", id); | |
641 | return; | |
642 | } | |
3cf2be58 | 643 | c->detach_user = fn; |
8e7895b8 | 644 | } |
645 | void | |
646 | channel_cancel_cleanup(int id) | |
647 | { | |
648 | Channel *c = channel_lookup(id); | |
649 | if (c == NULL) { | |
650 | log("channel_cancel_cleanup: %d: bad id", id); | |
651 | return; | |
652 | } | |
3cf2be58 | 653 | c->detach_user = NULL; |
8e7895b8 | 654 | } |
655 | void | |
656 | channel_register_filter(int id, channel_filter_fn *fn) | |
657 | { | |
658 | Channel *c = channel_lookup(id); | |
659 | if (c == NULL) { | |
660 | log("channel_register_filter: %d: bad id", id); | |
661 | return; | |
662 | } | |
663 | c->input_filter = fn; | |
664 | } | |
665 | ||
6ae2364d | 666 | void |
8e7895b8 | 667 | channel_set_fds(int id, int rfd, int wfd, int efd, |
668 | int extusage, int nonblock) | |
8efc0c15 | 669 | { |
8e7895b8 | 670 | Channel *c = channel_lookup(id); |
671 | if (c == NULL || c->type != SSH_CHANNEL_LARVAL) | |
672 | fatal("channel_activate for non-larval channel %d.", id); | |
673 | channel_register_fds(c, rfd, wfd, efd, extusage, nonblock); | |
674 | c->type = SSH_CHANNEL_OPEN; | |
675 | /* XXX window size? */ | |
676 | c->local_window = c->local_window_max = c->local_maxpacket * 2; | |
677 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); | |
678 | packet_put_int(c->remote_id); | |
679 | packet_put_int(c->local_window); | |
680 | packet_send(); | |
8efc0c15 | 681 | } |
682 | ||
aa3378df | 683 | /* |
7368a6c8 | 684 | * 'channel_pre*' are called just before select() to add any bits relevant to |
685 | * channels in the select bitmasks. | |
aa3378df | 686 | */ |
7368a6c8 | 687 | /* |
688 | * 'channel_post*': perform any appropriate operations for channels which | |
689 | * have events pending. | |
690 | */ | |
691 | typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset); | |
692 | chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE]; | |
693 | chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE]; | |
8efc0c15 | 694 | |
396c147e | 695 | static void |
7368a6c8 | 696 | channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset) |
8efc0c15 | 697 | { |
7368a6c8 | 698 | FD_SET(c->sock, readset); |
699 | } | |
5260325f | 700 | |
396c147e | 701 | static void |
97fb6912 | 702 | channel_pre_connecting(Channel *c, fd_set * readset, fd_set * writeset) |
703 | { | |
704 | debug3("channel %d: waiting for connection", c->self); | |
705 | FD_SET(c->sock, writeset); | |
706 | } | |
707 | ||
396c147e | 708 | static void |
7368a6c8 | 709 | channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset) |
710 | { | |
711 | if (buffer_len(&c->input) < packet_get_maxsize()) | |
712 | FD_SET(c->sock, readset); | |
713 | if (buffer_len(&c->output) > 0) | |
714 | FD_SET(c->sock, writeset); | |
715 | } | |
5260325f | 716 | |
396c147e | 717 | static void |
7368a6c8 | 718 | channel_pre_open_15(Channel *c, fd_set * readset, fd_set * writeset) |
719 | { | |
720 | /* test whether sockets are 'alive' for read/write */ | |
721 | if (c->istate == CHAN_INPUT_OPEN) | |
722 | if (buffer_len(&c->input) < packet_get_maxsize()) | |
723 | FD_SET(c->sock, readset); | |
724 | if (c->ostate == CHAN_OUTPUT_OPEN || | |
725 | c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
726 | if (buffer_len(&c->output) > 0) { | |
727 | FD_SET(c->sock, writeset); | |
728 | } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
729 | chan_obuf_empty(c); | |
730 | } | |
731 | } | |
732 | } | |
5260325f | 733 | |
396c147e | 734 | static void |
7e7327a1 | 735 | channel_pre_open_20(Channel *c, fd_set * readset, fd_set * writeset) |
736 | { | |
737 | if (c->istate == CHAN_INPUT_OPEN && | |
738 | c->remote_window > 0 && | |
739 | buffer_len(&c->input) < c->remote_window) | |
740 | FD_SET(c->rfd, readset); | |
741 | if (c->ostate == CHAN_OUTPUT_OPEN || | |
742 | c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
743 | if (buffer_len(&c->output) > 0) { | |
744 | FD_SET(c->wfd, writeset); | |
745 | } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
746 | chan_obuf_empty(c); | |
747 | } | |
748 | } | |
749 | /** XXX check close conditions, too */ | |
750 | if (c->efd != -1) { | |
751 | if (c->extended_usage == CHAN_EXTENDED_WRITE && | |
752 | buffer_len(&c->extended) > 0) | |
753 | FD_SET(c->efd, writeset); | |
754 | else if (c->extended_usage == CHAN_EXTENDED_READ && | |
755 | buffer_len(&c->extended) < c->remote_window) | |
756 | FD_SET(c->efd, readset); | |
757 | } | |
758 | } | |
759 | ||
396c147e | 760 | static void |
7368a6c8 | 761 | channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset) |
762 | { | |
763 | if (buffer_len(&c->input) == 0) { | |
764 | packet_start(SSH_MSG_CHANNEL_CLOSE); | |
765 | packet_put_int(c->remote_id); | |
766 | packet_send(); | |
767 | c->type = SSH_CHANNEL_CLOSED; | |
070adba2 | 768 | debug("channel %d: closing after input drain.", c->self); |
7368a6c8 | 769 | } |
770 | } | |
5260325f | 771 | |
396c147e | 772 | static void |
7368a6c8 | 773 | channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset) |
774 | { | |
775 | if (buffer_len(&c->output) == 0) | |
719fc62f | 776 | chan_mark_dead(c); |
6ae2364d | 777 | else |
7368a6c8 | 778 | FD_SET(c->sock, writeset); |
779 | } | |
5260325f | 780 | |
7368a6c8 | 781 | /* |
782 | * This is a special state for X11 authentication spoofing. An opened X11 | |
783 | * connection (when authentication spoofing is being done) remains in this | |
784 | * state until the first packet has been completely read. The authentication | |
785 | * data in that packet is then substituted by the real data if it matches the | |
786 | * fake data, and the channel is put into normal mode. | |
0b242b12 | 787 | * XXX All this happens at the client side. |
8e7895b8 | 788 | * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok |
7368a6c8 | 789 | */ |
396c147e | 790 | static int |
8e7895b8 | 791 | x11_open_helper(Buffer *b) |
7368a6c8 | 792 | { |
1e3b8b07 | 793 | u_char *ucp; |
794 | u_int proto_len, data_len; | |
5260325f | 795 | |
7368a6c8 | 796 | /* Check if the fixed size part of the packet is in buffer. */ |
8e7895b8 | 797 | if (buffer_len(b) < 12) |
7368a6c8 | 798 | return 0; |
799 | ||
800 | /* Parse the lengths of variable-length fields. */ | |
8e7895b8 | 801 | ucp = (u_char *) buffer_ptr(b); |
7368a6c8 | 802 | if (ucp[0] == 0x42) { /* Byte order MSB first. */ |
803 | proto_len = 256 * ucp[6] + ucp[7]; | |
804 | data_len = 256 * ucp[8] + ucp[9]; | |
805 | } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */ | |
806 | proto_len = ucp[6] + 256 * ucp[7]; | |
807 | data_len = ucp[8] + 256 * ucp[9]; | |
808 | } else { | |
809 | debug("Initial X11 packet contains bad byte order byte: 0x%x", | |
810 | ucp[0]); | |
811 | return -1; | |
812 | } | |
5260325f | 813 | |
7368a6c8 | 814 | /* Check if the whole packet is in buffer. */ |
8e7895b8 | 815 | if (buffer_len(b) < |
7368a6c8 | 816 | 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3)) |
817 | return 0; | |
5260325f | 818 | |
7368a6c8 | 819 | /* Check if authentication protocol matches. */ |
820 | if (proto_len != strlen(x11_saved_proto) || | |
821 | memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) { | |
822 | debug("X11 connection uses different authentication protocol."); | |
823 | return -1; | |
824 | } | |
825 | /* Check if authentication data matches our fake data. */ | |
826 | if (data_len != x11_fake_data_len || | |
827 | memcmp(ucp + 12 + ((proto_len + 3) & ~3), | |
828 | x11_fake_data, x11_fake_data_len) != 0) { | |
829 | debug("X11 auth data does not match fake data."); | |
830 | return -1; | |
831 | } | |
832 | /* Check fake data length */ | |
833 | if (x11_fake_data_len != x11_saved_data_len) { | |
834 | error("X11 fake_data_len %d != saved_data_len %d", | |
835 | x11_fake_data_len, x11_saved_data_len); | |
836 | return -1; | |
837 | } | |
838 | /* | |
839 | * Received authentication protocol and data match | |
840 | * our fake data. Substitute the fake data with real | |
841 | * data. | |
842 | */ | |
843 | memcpy(ucp + 12 + ((proto_len + 3) & ~3), | |
844 | x11_saved_data, x11_saved_data_len); | |
845 | return 1; | |
846 | } | |
5260325f | 847 | |
396c147e | 848 | static void |
7368a6c8 | 849 | channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset) |
850 | { | |
8e7895b8 | 851 | int ret = x11_open_helper(&c->output); |
7368a6c8 | 852 | if (ret == 1) { |
853 | /* Start normal processing for the channel. */ | |
854 | c->type = SSH_CHANNEL_OPEN; | |
a8be9f80 | 855 | channel_pre_open_13(c, readset, writeset); |
7368a6c8 | 856 | } else if (ret == -1) { |
857 | /* | |
858 | * We have received an X11 connection that has bad | |
859 | * authentication information. | |
860 | */ | |
54b974dc | 861 | log("X11 connection rejected because of wrong authentication."); |
7368a6c8 | 862 | buffer_clear(&c->input); |
863 | buffer_clear(&c->output); | |
489aa2e9 | 864 | channel_close_fd(&c->sock); |
7368a6c8 | 865 | c->sock = -1; |
866 | c->type = SSH_CHANNEL_CLOSED; | |
867 | packet_start(SSH_MSG_CHANNEL_CLOSE); | |
868 | packet_put_int(c->remote_id); | |
869 | packet_send(); | |
870 | } | |
871 | } | |
5260325f | 872 | |
396c147e | 873 | static void |
0b242b12 | 874 | channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset) |
7368a6c8 | 875 | { |
8e7895b8 | 876 | int ret = x11_open_helper(&c->output); |
7368a6c8 | 877 | if (ret == 1) { |
878 | c->type = SSH_CHANNEL_OPEN; | |
d0c832f3 | 879 | if (compat20) |
880 | channel_pre_open_20(c, readset, writeset); | |
881 | else | |
882 | channel_pre_open_15(c, readset, writeset); | |
7368a6c8 | 883 | } else if (ret == -1) { |
884 | debug("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate); | |
0b242b12 | 885 | chan_read_failed(c); /** force close? */ |
7368a6c8 | 886 | chan_write_failed(c); |
887 | debug("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate); | |
888 | } | |
889 | } | |
5260325f | 890 | |
28b9cb4d | 891 | /* try to decode a socks4 header */ |
396c147e | 892 | static int |
28b9cb4d | 893 | channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset) |
0490e609 | 894 | { |
895 | u_char *p, *host; | |
53b8fe68 | 896 | int len, have, i, found; |
28b9cb4d | 897 | char username[256]; |
0490e609 | 898 | struct { |
899 | u_int8_t version; | |
900 | u_int8_t command; | |
901 | u_int16_t dest_port; | |
28b9cb4d | 902 | struct in_addr dest_addr; |
0490e609 | 903 | } s4_req, s4_rsp; |
904 | ||
28b9cb4d | 905 | debug2("channel %d: decode socks4", c->self); |
53b8fe68 | 906 | |
907 | have = buffer_len(&c->input); | |
908 | len = sizeof(s4_req); | |
909 | if (have < len) | |
910 | return 0; | |
911 | p = buffer_ptr(&c->input); | |
912 | for (found = 0, i = len; i < have; i++) { | |
913 | if (p[i] == '\0') { | |
914 | found = 1; | |
915 | break; | |
916 | } | |
917 | if (i > 1024) { | |
918 | /* the peer is probably sending garbage */ | |
919 | debug("channel %d: decode socks4: too long", | |
920 | c->self); | |
921 | return -1; | |
922 | } | |
923 | } | |
924 | if (!found) | |
925 | return 0; | |
0490e609 | 926 | buffer_get(&c->input, (char *)&s4_req.version, 1); |
927 | buffer_get(&c->input, (char *)&s4_req.command, 1); | |
928 | buffer_get(&c->input, (char *)&s4_req.dest_port, 2); | |
28b9cb4d | 929 | buffer_get(&c->input, (char *)&s4_req.dest_addr, 4); |
53b8fe68 | 930 | have = buffer_len(&c->input); |
0490e609 | 931 | p = buffer_ptr(&c->input); |
932 | len = strlen(p); | |
6683b40f | 933 | debug2("channel %d: decode socks4: user %s/%d", c->self, p, len); |
0490e609 | 934 | if (len > have) |
28b9cb4d | 935 | fatal("channel %d: decode socks4: len %d > have %d", |
0490e609 | 936 | c->self, len, have); |
937 | strlcpy(username, p, sizeof(username)); | |
938 | buffer_consume(&c->input, len); | |
939 | buffer_consume(&c->input, 1); /* trailing '\0' */ | |
940 | ||
28b9cb4d | 941 | host = inet_ntoa(s4_req.dest_addr); |
0490e609 | 942 | strlcpy(c->path, host, sizeof(c->path)); |
943 | c->host_port = ntohs(s4_req.dest_port); | |
944 | ||
6683b40f | 945 | debug("channel %d: dynamic request: socks4 host %s port %u command %u", |
946 | c->self, host, c->host_port, s4_req.command); | |
0490e609 | 947 | |
28b9cb4d | 948 | if (s4_req.command != 1) { |
949 | debug("channel %d: cannot handle: socks4 cn %d", | |
950 | c->self, s4_req.command); | |
951 | return -1; | |
0490e609 | 952 | } |
28b9cb4d | 953 | s4_rsp.version = 0; /* vn: 0 for reply */ |
954 | s4_rsp.command = 90; /* cd: req granted */ | |
0490e609 | 955 | s4_rsp.dest_port = 0; /* ignored */ |
28b9cb4d | 956 | s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */ |
0490e609 | 957 | buffer_append(&c->output, (char *)&s4_rsp, sizeof(s4_rsp)); |
28b9cb4d | 958 | return 1; |
0490e609 | 959 | } |
960 | ||
28b9cb4d | 961 | /* dynamic port forwarding */ |
396c147e | 962 | static void |
28b9cb4d | 963 | channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset) |
964 | { | |
965 | u_char *p; | |
966 | int have, ret; | |
967 | ||
968 | have = buffer_len(&c->input); | |
969 | ||
970 | debug2("channel %d: pre_dynamic: have %d", c->self, have); | |
070adba2 | 971 | /* buffer_dump(&c->input); */ |
28b9cb4d | 972 | /* check if the fixed size part of the packet is in buffer. */ |
973 | if (have < 4) { | |
974 | /* need more */ | |
975 | FD_SET(c->sock, readset); | |
976 | return; | |
977 | } | |
978 | /* try to guess the protocol */ | |
979 | p = buffer_ptr(&c->input); | |
980 | switch (p[0]) { | |
6683b40f | 981 | case 0x04: |
982 | ret = channel_decode_socks4(c, readset, writeset); | |
983 | break; | |
28b9cb4d | 984 | default: |
985 | ret = -1; | |
986 | break; | |
987 | } | |
988 | if (ret < 0) { | |
719fc62f | 989 | chan_mark_dead(c); |
28b9cb4d | 990 | } else if (ret == 0) { |
991 | debug2("channel %d: pre_dynamic: need more", c->self); | |
992 | /* need more */ | |
993 | FD_SET(c->sock, readset); | |
994 | } else { | |
995 | /* switch to the next state */ | |
996 | c->type = SSH_CHANNEL_OPENING; | |
997 | port_open_helper(c, "direct-tcpip"); | |
998 | } | |
999 | } | |
0490e609 | 1000 | |
7368a6c8 | 1001 | /* This is our fake X11 server socket. */ |
396c147e | 1002 | static void |
7368a6c8 | 1003 | channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset) |
1004 | { | |
719fc62f | 1005 | Channel *nc; |
7368a6c8 | 1006 | struct sockaddr addr; |
719fc62f | 1007 | int newsock; |
7368a6c8 | 1008 | socklen_t addrlen; |
865ac82e | 1009 | char buf[16384], *remote_ipaddr; |
0b242b12 | 1010 | int remote_port; |
7368a6c8 | 1011 | |
1012 | if (FD_ISSET(c->sock, readset)) { | |
1013 | debug("X11 connection requested."); | |
1014 | addrlen = sizeof(addr); | |
1015 | newsock = accept(c->sock, &addr, &addrlen); | |
1016 | if (newsock < 0) { | |
1017 | error("accept: %.100s", strerror(errno)); | |
1018 | return; | |
5260325f | 1019 | } |
865ac82e | 1020 | remote_ipaddr = get_peer_ipaddr(newsock); |
0b242b12 | 1021 | remote_port = get_peer_port(newsock); |
7368a6c8 | 1022 | snprintf(buf, sizeof buf, "X11 connection from %.200s port %d", |
865ac82e | 1023 | remote_ipaddr, remote_port); |
0b242b12 | 1024 | |
719fc62f | 1025 | nc = channel_new("accepted x11 socket", |
0b242b12 | 1026 | SSH_CHANNEL_OPENING, newsock, newsock, -1, |
1027 | c->local_window_max, c->local_maxpacket, | |
a22aff1f | 1028 | 0, xstrdup(buf), 1); |
719fc62f | 1029 | if (nc == NULL) { |
1030 | close(newsock); | |
1031 | xfree(remote_ipaddr); | |
1032 | return; | |
1033 | } | |
0b242b12 | 1034 | if (compat20) { |
1035 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
1036 | packet_put_cstring("x11"); | |
719fc62f | 1037 | packet_put_int(nc->self); |
0b242b12 | 1038 | packet_put_int(c->local_window_max); |
1039 | packet_put_int(c->local_maxpacket); | |
865ac82e | 1040 | /* originator ipaddr and port */ |
1041 | packet_put_cstring(remote_ipaddr); | |
d0c832f3 | 1042 | if (datafellows & SSH_BUG_X11FWD) { |
1043 | debug("ssh2 x11 bug compat mode"); | |
1044 | } else { | |
1045 | packet_put_int(remote_port); | |
1046 | } | |
0b242b12 | 1047 | packet_send(); |
1048 | } else { | |
1049 | packet_start(SSH_SMSG_X11_OPEN); | |
719fc62f | 1050 | packet_put_int(nc->self); |
8e7895b8 | 1051 | if (packet_get_protocol_flags() & |
1052 | SSH_PROTOFLAG_HOST_IN_FWD_OPEN) | |
449c5ba5 | 1053 | packet_put_cstring(buf); |
0b242b12 | 1054 | packet_send(); |
1055 | } | |
865ac82e | 1056 | xfree(remote_ipaddr); |
8efc0c15 | 1057 | } |
8efc0c15 | 1058 | } |
1059 | ||
396c147e | 1060 | static void |
0490e609 | 1061 | port_open_helper(Channel *c, char *rtype) |
1062 | { | |
1063 | int direct; | |
1064 | char buf[1024]; | |
1065 | char *remote_ipaddr = get_peer_ipaddr(c->sock); | |
1066 | u_short remote_port = get_peer_port(c->sock); | |
1067 | ||
1068 | direct = (strcmp(rtype, "direct-tcpip") == 0); | |
1069 | ||
1070 | snprintf(buf, sizeof buf, | |
1071 | "%s: listening port %d for %.100s port %d, " | |
1072 | "connect from %.200s port %d", | |
1073 | rtype, c->listening_port, c->path, c->host_port, | |
1074 | remote_ipaddr, remote_port); | |
1075 | ||
1076 | xfree(c->remote_name); | |
1077 | c->remote_name = xstrdup(buf); | |
1078 | ||
1079 | if (compat20) { | |
1080 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
1081 | packet_put_cstring(rtype); | |
1082 | packet_put_int(c->self); | |
1083 | packet_put_int(c->local_window_max); | |
1084 | packet_put_int(c->local_maxpacket); | |
1085 | if (direct) { | |
1086 | /* target host, port */ | |
1087 | packet_put_cstring(c->path); | |
1088 | packet_put_int(c->host_port); | |
1089 | } else { | |
1090 | /* listen address, port */ | |
1091 | packet_put_cstring(c->path); | |
1092 | packet_put_int(c->listening_port); | |
1093 | } | |
1094 | /* originator host and port */ | |
1095 | packet_put_cstring(remote_ipaddr); | |
1096 | packet_put_int(remote_port); | |
1097 | packet_send(); | |
1098 | } else { | |
1099 | packet_start(SSH_MSG_PORT_OPEN); | |
1100 | packet_put_int(c->self); | |
1101 | packet_put_cstring(c->path); | |
1102 | packet_put_int(c->host_port); | |
8e7895b8 | 1103 | if (packet_get_protocol_flags() & |
1104 | SSH_PROTOFLAG_HOST_IN_FWD_OPEN) | |
0490e609 | 1105 | packet_put_cstring(c->remote_name); |
1106 | packet_send(); | |
1107 | } | |
1108 | xfree(remote_ipaddr); | |
1109 | } | |
1110 | ||
aa3378df | 1111 | /* |
7368a6c8 | 1112 | * This socket is listening for connections to a forwarded TCP/IP port. |
aa3378df | 1113 | */ |
396c147e | 1114 | static void |
7368a6c8 | 1115 | channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset) |
1116 | { | |
0490e609 | 1117 | Channel *nc; |
7368a6c8 | 1118 | struct sockaddr addr; |
719fc62f | 1119 | int newsock, nextstate; |
7368a6c8 | 1120 | socklen_t addrlen; |
0490e609 | 1121 | char *rtype; |
fa08c86b | 1122 | |
7368a6c8 | 1123 | if (FD_ISSET(c->sock, readset)) { |
1124 | debug("Connection to port %d forwarding " | |
1125 | "to %.100s port %d requested.", | |
1126 | c->listening_port, c->path, c->host_port); | |
0490e609 | 1127 | |
1128 | rtype = (c->type == SSH_CHANNEL_RPORT_LISTENER) ? | |
1129 | "forwarded-tcpip" : "direct-tcpip"; | |
97430469 | 1130 | nextstate = (c->host_port == 0 && |
1131 | c->type != SSH_CHANNEL_RPORT_LISTENER) ? | |
1132 | SSH_CHANNEL_DYNAMIC : SSH_CHANNEL_OPENING; | |
0490e609 | 1133 | |
7368a6c8 | 1134 | addrlen = sizeof(addr); |
1135 | newsock = accept(c->sock, &addr, &addrlen); | |
1136 | if (newsock < 0) { | |
1137 | error("accept: %.100s", strerror(errno)); | |
1138 | return; | |
1139 | } | |
719fc62f | 1140 | nc = channel_new(rtype, |
0490e609 | 1141 | nextstate, newsock, newsock, -1, |
7368a6c8 | 1142 | c->local_window_max, c->local_maxpacket, |
0490e609 | 1143 | 0, xstrdup(rtype), 1); |
0490e609 | 1144 | if (nc == NULL) { |
719fc62f | 1145 | error("channel_post_port_listener: no new channel:"); |
1146 | close(newsock); | |
0490e609 | 1147 | return; |
7368a6c8 | 1148 | } |
0490e609 | 1149 | nc->listening_port = c->listening_port; |
1150 | nc->host_port = c->host_port; | |
1151 | strlcpy(nc->path, c->path, sizeof(nc->path)); | |
1152 | ||
1153 | if (nextstate != SSH_CHANNEL_DYNAMIC) | |
1154 | port_open_helper(nc, rtype); | |
7368a6c8 | 1155 | } |
1156 | } | |
8efc0c15 | 1157 | |
7368a6c8 | 1158 | /* |
1159 | * This is the authentication agent socket listening for connections from | |
1160 | * clients. | |
1161 | */ | |
396c147e | 1162 | static void |
7368a6c8 | 1163 | channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset) |
8efc0c15 | 1164 | { |
719fc62f | 1165 | Channel *nc; |
8e7895b8 | 1166 | char *name; |
719fc62f | 1167 | int newsock; |
5260325f | 1168 | struct sockaddr addr; |
48e671d5 | 1169 | socklen_t addrlen; |
5260325f | 1170 | |
7368a6c8 | 1171 | if (FD_ISSET(c->sock, readset)) { |
1172 | addrlen = sizeof(addr); | |
1173 | newsock = accept(c->sock, &addr, &addrlen); | |
1174 | if (newsock < 0) { | |
1175 | error("accept from auth socket: %.100s", strerror(errno)); | |
1176 | return; | |
1177 | } | |
8e7895b8 | 1178 | name = xstrdup("accepted auth socket"); |
719fc62f | 1179 | nc = channel_new("accepted auth socket", |
fa08c86b | 1180 | SSH_CHANNEL_OPENING, newsock, newsock, -1, |
1181 | c->local_window_max, c->local_maxpacket, | |
8e7895b8 | 1182 | 0, name, 1); |
719fc62f | 1183 | if (nc == NULL) { |
1184 | error("channel_post_auth_listener: channel_new failed"); | |
8e7895b8 | 1185 | xfree(name); |
719fc62f | 1186 | close(newsock); |
1187 | } | |
fa08c86b | 1188 | if (compat20) { |
1189 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
1190 | packet_put_cstring("auth-agent@openssh.com"); | |
719fc62f | 1191 | packet_put_int(nc->self); |
fa08c86b | 1192 | packet_put_int(c->local_window_max); |
1193 | packet_put_int(c->local_maxpacket); | |
1194 | } else { | |
1195 | packet_start(SSH_SMSG_AGENT_OPEN); | |
719fc62f | 1196 | packet_put_int(nc->self); |
fa08c86b | 1197 | } |
7368a6c8 | 1198 | packet_send(); |
1199 | } | |
1200 | } | |
5260325f | 1201 | |
396c147e | 1202 | static void |
97fb6912 | 1203 | channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset) |
1204 | { | |
d18e0850 | 1205 | int err = 0; |
8ab2cb35 | 1206 | socklen_t sz = sizeof(err); |
d18e0850 | 1207 | |
97fb6912 | 1208 | if (FD_ISSET(c->sock, writeset)) { |
d18e0850 | 1209 | if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, (char *)&err, |
1210 | &sz) < 0) { | |
1211 | err = errno; | |
1212 | error("getsockopt SO_ERROR failed"); | |
1213 | } | |
1214 | if (err == 0) { | |
1215 | debug("channel %d: connected", c->self); | |
1216 | c->type = SSH_CHANNEL_OPEN; | |
1217 | if (compat20) { | |
1218 | packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1219 | packet_put_int(c->remote_id); | |
1220 | packet_put_int(c->self); | |
1221 | packet_put_int(c->local_window); | |
1222 | packet_put_int(c->local_maxpacket); | |
1223 | } else { | |
1224 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1225 | packet_put_int(c->remote_id); | |
1226 | packet_put_int(c->self); | |
1227 | } | |
97fb6912 | 1228 | } else { |
d18e0850 | 1229 | debug("channel %d: not connected: %s", |
1230 | c->self, strerror(err)); | |
1231 | if (compat20) { | |
1232 | packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE); | |
1233 | packet_put_int(c->remote_id); | |
1234 | packet_put_int(SSH2_OPEN_CONNECT_FAILED); | |
1235 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { | |
1236 | packet_put_cstring(strerror(err)); | |
1237 | packet_put_cstring(""); | |
1238 | } | |
97fb6912 | 1239 | } else { |
d18e0850 | 1240 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); |
1241 | packet_put_int(c->remote_id); | |
97fb6912 | 1242 | } |
d18e0850 | 1243 | chan_mark_dead(c); |
97fb6912 | 1244 | } |
d18e0850 | 1245 | packet_send(); |
97fb6912 | 1246 | } |
1247 | } | |
1248 | ||
396c147e | 1249 | static int |
7368a6c8 | 1250 | channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset) |
1251 | { | |
1252 | char buf[16*1024]; | |
1253 | int len; | |
1254 | ||
6fd8622b | 1255 | if (c->rfd != -1 && |
7368a6c8 | 1256 | FD_ISSET(c->rfd, readset)) { |
1257 | len = read(c->rfd, buf, sizeof(buf)); | |
0fbe8c74 | 1258 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1259 | return 1; | |
7368a6c8 | 1260 | if (len <= 0) { |
0b242b12 | 1261 | debug("channel %d: read<=0 rfd %d len %d", |
7368a6c8 | 1262 | c->self, c->rfd, len); |
28b9cb4d | 1263 | if (c->type != SSH_CHANNEL_OPEN) { |
1264 | debug("channel %d: not open", c->self); | |
719fc62f | 1265 | chan_mark_dead(c); |
0490e609 | 1266 | return -1; |
28b9cb4d | 1267 | } else if (compat13) { |
7368a6c8 | 1268 | buffer_consume(&c->output, buffer_len(&c->output)); |
1269 | c->type = SSH_CHANNEL_INPUT_DRAINING; | |
8e7895b8 | 1270 | debug("channel %d: input draining.", c->self); |
7368a6c8 | 1271 | } else { |
1272 | chan_read_failed(c); | |
5260325f | 1273 | } |
7368a6c8 | 1274 | return -1; |
1275 | } | |
2e73a022 | 1276 | if(c->input_filter != NULL) { |
1277 | if (c->input_filter(c, buf, len) == -1) { | |
070adba2 | 1278 | debug("channel %d: filter stops", c->self); |
2e73a022 | 1279 | chan_read_failed(c); |
1280 | } | |
1281 | } else { | |
1282 | buffer_append(&c->input, buf, len); | |
1283 | } | |
7368a6c8 | 1284 | } |
1285 | return 1; | |
1286 | } | |
396c147e | 1287 | static int |
7368a6c8 | 1288 | channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset) |
1289 | { | |
95ce5599 | 1290 | struct termios tio; |
7368a6c8 | 1291 | int len; |
1292 | ||
1293 | /* Send buffered output data to the socket. */ | |
6fd8622b | 1294 | if (c->wfd != -1 && |
7368a6c8 | 1295 | FD_ISSET(c->wfd, writeset) && |
1296 | buffer_len(&c->output) > 0) { | |
1297 | len = write(c->wfd, buffer_ptr(&c->output), | |
0fbe8c74 | 1298 | buffer_len(&c->output)); |
1299 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) | |
1300 | return 1; | |
7368a6c8 | 1301 | if (len <= 0) { |
28b9cb4d | 1302 | if (c->type != SSH_CHANNEL_OPEN) { |
1303 | debug("channel %d: not open", c->self); | |
719fc62f | 1304 | chan_mark_dead(c); |
28b9cb4d | 1305 | return -1; |
1306 | } else if (compat13) { | |
7368a6c8 | 1307 | buffer_consume(&c->output, buffer_len(&c->output)); |
8e7895b8 | 1308 | debug("channel %d: input draining.", c->self); |
7368a6c8 | 1309 | c->type = SSH_CHANNEL_INPUT_DRAINING; |
1310 | } else { | |
1311 | chan_write_failed(c); | |
5260325f | 1312 | } |
7368a6c8 | 1313 | return -1; |
1314 | } | |
0ae4fe1d | 1315 | if (compat20 && c->isatty) { |
0ae4fe1d | 1316 | if (tcgetattr(c->wfd, &tio) == 0 && |
1317 | !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) { | |
1318 | /* | |
1319 | * Simulate echo to reduce the impact of | |
355724fc | 1320 | * traffic analysis. We need to match the |
95ce5599 | 1321 | * size of a SSH2_MSG_CHANNEL_DATA message |
1322 | * (4 byte channel id + data) | |
0ae4fe1d | 1323 | */ |
95ce5599 | 1324 | packet_send_ignore(4 + len); |
0ae4fe1d | 1325 | packet_send(); |
0ae4fe1d | 1326 | } |
1327 | } | |
7368a6c8 | 1328 | buffer_consume(&c->output, len); |
7e7327a1 | 1329 | if (compat20 && len > 0) { |
1330 | c->local_consumed += len; | |
1331 | } | |
1332 | } | |
1333 | return 1; | |
1334 | } | |
396c147e | 1335 | static int |
7e7327a1 | 1336 | channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset) |
1337 | { | |
1338 | char buf[16*1024]; | |
1339 | int len; | |
1340 | ||
8ce64345 | 1341 | /** XXX handle drain efd, too */ |
7e7327a1 | 1342 | if (c->efd != -1) { |
1343 | if (c->extended_usage == CHAN_EXTENDED_WRITE && | |
1344 | FD_ISSET(c->efd, writeset) && | |
1345 | buffer_len(&c->extended) > 0) { | |
1346 | len = write(c->efd, buffer_ptr(&c->extended), | |
1347 | buffer_len(&c->extended)); | |
de273eef | 1348 | debug2("channel %d: written %d to efd %d", |
7e7327a1 | 1349 | c->self, len, c->efd); |
ee55dacf | 1350 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1351 | return 1; | |
1352 | if (len <= 0) { | |
1353 | debug2("channel %d: closing write-efd %d", | |
1354 | c->self, c->efd); | |
489aa2e9 | 1355 | channel_close_fd(&c->efd); |
ee55dacf | 1356 | } else { |
7e7327a1 | 1357 | buffer_consume(&c->extended, len); |
1358 | c->local_consumed += len; | |
1359 | } | |
1360 | } else if (c->extended_usage == CHAN_EXTENDED_READ && | |
1361 | FD_ISSET(c->efd, readset)) { | |
1362 | len = read(c->efd, buf, sizeof(buf)); | |
de273eef | 1363 | debug2("channel %d: read %d from efd %d", |
7e7327a1 | 1364 | c->self, len, c->efd); |
ee55dacf | 1365 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1366 | return 1; | |
1367 | if (len <= 0) { | |
1368 | debug2("channel %d: closing read-efd %d", | |
8ce64345 | 1369 | c->self, c->efd); |
489aa2e9 | 1370 | channel_close_fd(&c->efd); |
ee55dacf | 1371 | } else { |
7e7327a1 | 1372 | buffer_append(&c->extended, buf, len); |
ee55dacf | 1373 | } |
7e7327a1 | 1374 | } |
1375 | } | |
1376 | return 1; | |
1377 | } | |
396c147e | 1378 | static int |
ee55dacf | 1379 | channel_check_window(Channel *c) |
7e7327a1 | 1380 | { |
28b9cb4d | 1381 | if (c->type == SSH_CHANNEL_OPEN && |
1382 | !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) && | |
7e7327a1 | 1383 | c->local_window < c->local_window_max/2 && |
1384 | c->local_consumed > 0) { | |
1385 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); | |
1386 | packet_put_int(c->remote_id); | |
1387 | packet_put_int(c->local_consumed); | |
1388 | packet_send(); | |
de273eef | 1389 | debug2("channel %d: window %d sent adjust %d", |
7e7327a1 | 1390 | c->self, c->local_window, |
1391 | c->local_consumed); | |
1392 | c->local_window += c->local_consumed; | |
1393 | c->local_consumed = 0; | |
7368a6c8 | 1394 | } |
1395 | return 1; | |
1396 | } | |
5260325f | 1397 | |
396c147e | 1398 | static void |
7368a6c8 | 1399 | channel_post_open_1(Channel *c, fd_set * readset, fd_set * writeset) |
1400 | { | |
1401 | channel_handle_rfd(c, readset, writeset); | |
1402 | channel_handle_wfd(c, readset, writeset); | |
1403 | } | |
aa3378df | 1404 | |
396c147e | 1405 | static void |
7e7327a1 | 1406 | channel_post_open_2(Channel *c, fd_set * readset, fd_set * writeset) |
1407 | { | |
1408 | channel_handle_rfd(c, readset, writeset); | |
1409 | channel_handle_wfd(c, readset, writeset); | |
1410 | channel_handle_efd(c, readset, writeset); | |
ee55dacf | 1411 | |
1412 | channel_check_window(c); | |
7e7327a1 | 1413 | } |
1414 | ||
396c147e | 1415 | static void |
7368a6c8 | 1416 | channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset) |
1417 | { | |
1418 | int len; | |
1419 | /* Send buffered output data to the socket. */ | |
1420 | if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) { | |
1421 | len = write(c->sock, buffer_ptr(&c->output), | |
1422 | buffer_len(&c->output)); | |
1423 | if (len <= 0) | |
1424 | buffer_consume(&c->output, buffer_len(&c->output)); | |
1425 | else | |
1426 | buffer_consume(&c->output, len); | |
1427 | } | |
1428 | } | |
5260325f | 1429 | |
396c147e | 1430 | static void |
7e7327a1 | 1431 | channel_handler_init_20(void) |
1432 | { | |
1433 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_20; | |
0b242b12 | 1434 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; |
7e7327a1 | 1435 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; |
fa08c86b | 1436 | channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener; |
0b242b12 | 1437 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; |
fa08c86b | 1438 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; |
97fb6912 | 1439 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1440 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7e7327a1 | 1441 | |
1442 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_2; | |
1443 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
fa08c86b | 1444 | channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener; |
0b242b12 | 1445 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; |
fa08c86b | 1446 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; |
97fb6912 | 1447 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
28b9cb4d | 1448 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_2; |
7e7327a1 | 1449 | } |
1450 | ||
396c147e | 1451 | static void |
7368a6c8 | 1452 | channel_handler_init_13(void) |
1453 | { | |
1454 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13; | |
1455 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13; | |
1456 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; | |
1457 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; | |
1458 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; | |
1459 | channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining; | |
1460 | channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining; | |
97fb6912 | 1461 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1462 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7368a6c8 | 1463 | |
1464 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1; | |
1465 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; | |
1466 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
1467 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; | |
1468 | channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13; | |
97fb6912 | 1469 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
28b9cb4d | 1470 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1; |
7368a6c8 | 1471 | } |
5260325f | 1472 | |
396c147e | 1473 | static void |
7368a6c8 | 1474 | channel_handler_init_15(void) |
1475 | { | |
1476 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_15; | |
0b242b12 | 1477 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; |
7368a6c8 | 1478 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; |
1479 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; | |
1480 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; | |
97fb6912 | 1481 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1482 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7368a6c8 | 1483 | |
1484 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; | |
1485 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
1486 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; | |
1487 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1; | |
97fb6912 | 1488 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
28b9cb4d | 1489 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1; |
7368a6c8 | 1490 | } |
1491 | ||
396c147e | 1492 | static void |
7368a6c8 | 1493 | channel_handler_init(void) |
1494 | { | |
1495 | int i; | |
1496 | for(i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) { | |
1497 | channel_pre[i] = NULL; | |
1498 | channel_post[i] = NULL; | |
1499 | } | |
7e7327a1 | 1500 | if (compat20) |
1501 | channel_handler_init_20(); | |
1502 | else if (compat13) | |
7368a6c8 | 1503 | channel_handler_init_13(); |
1504 | else | |
1505 | channel_handler_init_15(); | |
1506 | } | |
1507 | ||
396c147e | 1508 | static void |
7368a6c8 | 1509 | channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset) |
1510 | { | |
1511 | static int did_init = 0; | |
1512 | int i; | |
1513 | Channel *c; | |
1514 | ||
1515 | if (!did_init) { | |
1516 | channel_handler_init(); | |
1517 | did_init = 1; | |
1518 | } | |
1519 | for (i = 0; i < channels_alloc; i++) { | |
719fc62f | 1520 | c = channels[i]; |
1521 | if (c == NULL) | |
5260325f | 1522 | continue; |
6fd8622b | 1523 | if (ftab[c->type] != NULL) |
1524 | (*ftab[c->type])(c, readset, writeset); | |
ee55dacf | 1525 | if (chan_is_dead(c)) { |
1526 | /* | |
1527 | * we have to remove the fd's from the select mask | |
1528 | * before the channels are free'd and the fd's are | |
1529 | * closed | |
1530 | */ | |
1531 | if (c->wfd != -1) | |
1532 | FD_CLR(c->wfd, writeset); | |
1533 | if (c->rfd != -1) | |
1534 | FD_CLR(c->rfd, readset); | |
1535 | if (c->efd != -1) { | |
1536 | if (c->extended_usage == CHAN_EXTENDED_READ) | |
1537 | FD_CLR(c->efd, readset); | |
1538 | if (c->extended_usage == CHAN_EXTENDED_WRITE) | |
1539 | FD_CLR(c->efd, writeset); | |
1540 | } | |
719fc62f | 1541 | channel_free(c); |
ee55dacf | 1542 | } |
8efc0c15 | 1543 | } |
8efc0c15 | 1544 | } |
1545 | ||
8e7895b8 | 1546 | /* |
1547 | * Allocate/update select bitmasks and add any bits relevant to channels in | |
1548 | * select bitmasks. | |
1549 | */ | |
6ae2364d | 1550 | void |
c422989b | 1551 | channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp, |
489aa2e9 | 1552 | int *nallocp, int rekeying) |
7368a6c8 | 1553 | { |
39929cdb | 1554 | int n; |
1555 | u_int sz; | |
1556 | ||
1557 | n = MAX(*maxfdp, channel_max_fd); | |
1558 | ||
1559 | sz = howmany(n+1, NFDBITS) * sizeof(fd_mask); | |
489aa2e9 | 1560 | /* perhaps check sz < nalloc/2 and shrink? */ |
1561 | if (*readsetp == NULL || sz > *nallocp) { | |
1562 | *readsetp = xrealloc(*readsetp, sz); | |
1563 | *writesetp = xrealloc(*writesetp, sz); | |
1564 | *nallocp = sz; | |
39929cdb | 1565 | } |
489aa2e9 | 1566 | *maxfdp = n; |
39929cdb | 1567 | memset(*readsetp, 0, sz); |
1568 | memset(*writesetp, 0, sz); | |
1569 | ||
c422989b | 1570 | if (!rekeying) |
1571 | channel_handler(channel_pre, *readsetp, *writesetp); | |
7368a6c8 | 1572 | } |
1573 | ||
8e7895b8 | 1574 | /* |
1575 | * After select, perform any appropriate operations for channels which have | |
1576 | * events pending. | |
1577 | */ | |
6ae2364d | 1578 | void |
7368a6c8 | 1579 | channel_after_select(fd_set * readset, fd_set * writeset) |
1580 | { | |
1581 | channel_handler(channel_post, readset, writeset); | |
1582 | } | |
1583 | ||
8e7895b8 | 1584 | |
39929cdb | 1585 | /* If there is data to send to the connection, enqueue some of it now. */ |
8efc0c15 | 1586 | |
6ae2364d | 1587 | void |
5260325f | 1588 | channel_output_poll() |
8efc0c15 | 1589 | { |
5260325f | 1590 | int len, i; |
7368a6c8 | 1591 | Channel *c; |
5260325f | 1592 | |
1593 | for (i = 0; i < channels_alloc; i++) { | |
719fc62f | 1594 | c = channels[i]; |
1595 | if (c == NULL) | |
1596 | continue; | |
48e671d5 | 1597 | |
8e7895b8 | 1598 | /* |
1599 | * We are only interested in channels that can have buffered | |
1600 | * incoming data. | |
1601 | */ | |
48e671d5 | 1602 | if (compat13) { |
7368a6c8 | 1603 | if (c->type != SSH_CHANNEL_OPEN && |
1604 | c->type != SSH_CHANNEL_INPUT_DRAINING) | |
48e671d5 | 1605 | continue; |
1606 | } else { | |
7368a6c8 | 1607 | if (c->type != SSH_CHANNEL_OPEN) |
48e671d5 | 1608 | continue; |
48e671d5 | 1609 | } |
e78a59f5 | 1610 | if (compat20 && |
1611 | (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) { | |
ee55dacf | 1612 | /* XXX is this true? */ |
61f8a1d1 | 1613 | debug2("channel %d: no data after CLOSE", c->self); |
7e7327a1 | 1614 | continue; |
1615 | } | |
5260325f | 1616 | |
1617 | /* Get the amount of buffered data for this channel. */ | |
ee55dacf | 1618 | if ((c->istate == CHAN_INPUT_OPEN || |
1619 | c->istate == CHAN_INPUT_WAIT_DRAIN) && | |
1620 | (len = buffer_len(&c->input)) > 0) { | |
8e7895b8 | 1621 | /* |
1622 | * Send some data for the other side over the secure | |
1623 | * connection. | |
1624 | */ | |
7e7327a1 | 1625 | if (compat20) { |
1626 | if (len > c->remote_window) | |
1627 | len = c->remote_window; | |
1628 | if (len > c->remote_maxpacket) | |
1629 | len = c->remote_maxpacket; | |
5260325f | 1630 | } else { |
7e7327a1 | 1631 | if (packet_is_interactive()) { |
1632 | if (len > 1024) | |
1633 | len = 512; | |
1634 | } else { | |
1635 | /* Keep the packets at reasonable size. */ | |
1636 | if (len > packet_get_maxsize()/2) | |
1637 | len = packet_get_maxsize()/2; | |
1638 | } | |
5260325f | 1639 | } |
7368a6c8 | 1640 | if (len > 0) { |
7e7327a1 | 1641 | packet_start(compat20 ? |
1642 | SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA); | |
7368a6c8 | 1643 | packet_put_int(c->remote_id); |
1644 | packet_put_string(buffer_ptr(&c->input), len); | |
1645 | packet_send(); | |
1646 | buffer_consume(&c->input, len); | |
1647 | c->remote_window -= len; | |
7368a6c8 | 1648 | } |
1649 | } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) { | |
5260325f | 1650 | if (compat13) |
1651 | fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3"); | |
aa3378df | 1652 | /* |
1653 | * input-buffer is empty and read-socket shutdown: | |
1654 | * tell peer, that we will not send more data: send IEOF | |
1655 | */ | |
7368a6c8 | 1656 | chan_ibuf_empty(c); |
5260325f | 1657 | } |
7e7327a1 | 1658 | /* Send extended data, i.e. stderr */ |
1659 | if (compat20 && | |
1660 | c->remote_window > 0 && | |
1661 | (len = buffer_len(&c->extended)) > 0 && | |
1662 | c->extended_usage == CHAN_EXTENDED_READ) { | |
ee55dacf | 1663 | debug2("channel %d: rwin %d elen %d euse %d", |
1664 | c->self, c->remote_window, buffer_len(&c->extended), | |
1665 | c->extended_usage); | |
7e7327a1 | 1666 | if (len > c->remote_window) |
1667 | len = c->remote_window; | |
1668 | if (len > c->remote_maxpacket) | |
1669 | len = c->remote_maxpacket; | |
1670 | packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA); | |
1671 | packet_put_int(c->remote_id); | |
1672 | packet_put_int(SSH2_EXTENDED_DATA_STDERR); | |
1673 | packet_put_string(buffer_ptr(&c->extended), len); | |
1674 | packet_send(); | |
1675 | buffer_consume(&c->extended, len); | |
1676 | c->remote_window -= len; | |
ee55dacf | 1677 | debug2("channel %d: sent ext data %d", c->self, len); |
7e7327a1 | 1678 | } |
8efc0c15 | 1679 | } |
8efc0c15 | 1680 | } |
1681 | ||
8e7895b8 | 1682 | |
1683 | /* -- protocol input */ | |
8efc0c15 | 1684 | |
6ae2364d | 1685 | void |
188adeb2 | 1686 | channel_input_data(int type, int plen, void *ctxt) |
8efc0c15 | 1687 | { |
48e671d5 | 1688 | int id; |
5260325f | 1689 | char *data; |
1e3b8b07 | 1690 | u_int data_len; |
7368a6c8 | 1691 | Channel *c; |
5260325f | 1692 | |
1693 | /* Get the channel number and verify it. */ | |
48e671d5 | 1694 | id = packet_get_int(); |
7368a6c8 | 1695 | c = channel_lookup(id); |
1696 | if (c == NULL) | |
48e671d5 | 1697 | packet_disconnect("Received data for nonexistent channel %d.", id); |
5260325f | 1698 | |
1699 | /* Ignore any data for non-open channels (might happen on close) */ | |
7368a6c8 | 1700 | if (c->type != SSH_CHANNEL_OPEN && |
1701 | c->type != SSH_CHANNEL_X11_OPEN) | |
48e671d5 | 1702 | return; |
1703 | ||
1704 | /* same for protocol 1.5 if output end is no longer open */ | |
7368a6c8 | 1705 | if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) |
5260325f | 1706 | return; |
1707 | ||
1708 | /* Get the data. */ | |
1709 | data = packet_get_string(&data_len); | |
6ae2364d | 1710 | packet_done(); |
7368a6c8 | 1711 | |
7e7327a1 | 1712 | if (compat20){ |
1713 | if (data_len > c->local_maxpacket) { | |
1714 | log("channel %d: rcvd big packet %d, maxpack %d", | |
1715 | c->self, data_len, c->local_maxpacket); | |
1716 | } | |
1717 | if (data_len > c->local_window) { | |
1718 | log("channel %d: rcvd too much data %d, win %d", | |
1719 | c->self, data_len, c->local_window); | |
1720 | xfree(data); | |
1721 | return; | |
1722 | } | |
1723 | c->local_window -= data_len; | |
1724 | }else{ | |
1725 | packet_integrity_check(plen, 4 + 4 + data_len, type); | |
1726 | } | |
7368a6c8 | 1727 | buffer_append(&c->output, data, data_len); |
5260325f | 1728 | xfree(data); |
8efc0c15 | 1729 | } |
8e7895b8 | 1730 | |
6ae2364d | 1731 | void |
188adeb2 | 1732 | channel_input_extended_data(int type, int plen, void *ctxt) |
7e7327a1 | 1733 | { |
1734 | int id; | |
1735 | int tcode; | |
1736 | char *data; | |
1e3b8b07 | 1737 | u_int data_len; |
7e7327a1 | 1738 | Channel *c; |
1739 | ||
1740 | /* Get the channel number and verify it. */ | |
1741 | id = packet_get_int(); | |
1742 | c = channel_lookup(id); | |
1743 | ||
1744 | if (c == NULL) | |
1745 | packet_disconnect("Received extended_data for bad channel %d.", id); | |
1746 | if (c->type != SSH_CHANNEL_OPEN) { | |
1747 | log("channel %d: ext data for non open", id); | |
1748 | return; | |
1749 | } | |
1750 | tcode = packet_get_int(); | |
1751 | if (c->efd == -1 || | |
1752 | c->extended_usage != CHAN_EXTENDED_WRITE || | |
1753 | tcode != SSH2_EXTENDED_DATA_STDERR) { | |
1754 | log("channel %d: bad ext data", c->self); | |
1755 | return; | |
1756 | } | |
1757 | data = packet_get_string(&data_len); | |
6ae2364d | 1758 | packet_done(); |
7e7327a1 | 1759 | if (data_len > c->local_window) { |
1760 | log("channel %d: rcvd too much extended_data %d, win %d", | |
1761 | c->self, data_len, c->local_window); | |
1762 | xfree(data); | |
1763 | return; | |
1764 | } | |
de273eef | 1765 | debug2("channel %d: rcvd ext data %d", c->self, data_len); |
7e7327a1 | 1766 | c->local_window -= data_len; |
1767 | buffer_append(&c->extended, data, data_len); | |
1768 | xfree(data); | |
1769 | } | |
1770 | ||
6ae2364d | 1771 | void |
188adeb2 | 1772 | channel_input_ieof(int type, int plen, void *ctxt) |
7368a6c8 | 1773 | { |
1774 | int id; | |
1775 | Channel *c; | |
1776 | ||
1777 | packet_integrity_check(plen, 4, type); | |
1778 | ||
1779 | id = packet_get_int(); | |
1780 | c = channel_lookup(id); | |
1781 | if (c == NULL) | |
1782 | packet_disconnect("Received ieof for nonexistent channel %d.", id); | |
1783 | chan_rcvd_ieof(c); | |
1784 | } | |
8efc0c15 | 1785 | |
6ae2364d | 1786 | void |
188adeb2 | 1787 | channel_input_close(int type, int plen, void *ctxt) |
8efc0c15 | 1788 | { |
7368a6c8 | 1789 | int id; |
1790 | Channel *c; | |
5260325f | 1791 | |
7368a6c8 | 1792 | packet_integrity_check(plen, 4, type); |
1793 | ||
1794 | id = packet_get_int(); | |
1795 | c = channel_lookup(id); | |
1796 | if (c == NULL) | |
1797 | packet_disconnect("Received close for nonexistent channel %d.", id); | |
aa3378df | 1798 | |
1799 | /* | |
1800 | * Send a confirmation that we have closed the channel and no more | |
1801 | * data is coming for it. | |
1802 | */ | |
5260325f | 1803 | packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION); |
7368a6c8 | 1804 | packet_put_int(c->remote_id); |
5260325f | 1805 | packet_send(); |
1806 | ||
aa3378df | 1807 | /* |
1808 | * If the channel is in closed state, we have sent a close request, | |
1809 | * and the other side will eventually respond with a confirmation. | |
1810 | * Thus, we cannot free the channel here, because then there would be | |
1811 | * no-one to receive the confirmation. The channel gets freed when | |
1812 | * the confirmation arrives. | |
1813 | */ | |
7368a6c8 | 1814 | if (c->type != SSH_CHANNEL_CLOSED) { |
aa3378df | 1815 | /* |
1816 | * Not a closed channel - mark it as draining, which will | |
1817 | * cause it to be freed later. | |
1818 | */ | |
7368a6c8 | 1819 | buffer_consume(&c->input, buffer_len(&c->input)); |
1820 | c->type = SSH_CHANNEL_OUTPUT_DRAINING; | |
5260325f | 1821 | } |
8efc0c15 | 1822 | } |
1823 | ||
7368a6c8 | 1824 | /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */ |
6ae2364d | 1825 | void |
188adeb2 | 1826 | channel_input_oclose(int type, int plen, void *ctxt) |
8efc0c15 | 1827 | { |
7368a6c8 | 1828 | int id = packet_get_int(); |
1829 | Channel *c = channel_lookup(id); | |
1830 | packet_integrity_check(plen, 4, type); | |
1831 | if (c == NULL) | |
1832 | packet_disconnect("Received oclose for nonexistent channel %d.", id); | |
1833 | chan_rcvd_oclose(c); | |
8efc0c15 | 1834 | } |
1835 | ||
6ae2364d | 1836 | void |
188adeb2 | 1837 | channel_input_close_confirmation(int type, int plen, void *ctxt) |
7368a6c8 | 1838 | { |
1839 | int id = packet_get_int(); | |
1840 | Channel *c = channel_lookup(id); | |
1841 | ||
6ae2364d | 1842 | packet_done(); |
7368a6c8 | 1843 | if (c == NULL) |
1844 | packet_disconnect("Received close confirmation for " | |
1845 | "out-of-range channel %d.", id); | |
1846 | if (c->type != SSH_CHANNEL_CLOSED) | |
1847 | packet_disconnect("Received close confirmation for " | |
1848 | "non-closed channel %d (type %d).", id, c->type); | |
719fc62f | 1849 | channel_free(c); |
7368a6c8 | 1850 | } |
8efc0c15 | 1851 | |
6ae2364d | 1852 | void |
188adeb2 | 1853 | channel_input_open_confirmation(int type, int plen, void *ctxt) |
8efc0c15 | 1854 | { |
7368a6c8 | 1855 | int id, remote_id; |
1856 | Channel *c; | |
5260325f | 1857 | |
7e7327a1 | 1858 | if (!compat20) |
1859 | packet_integrity_check(plen, 4 + 4, type); | |
5260325f | 1860 | |
7368a6c8 | 1861 | id = packet_get_int(); |
1862 | c = channel_lookup(id); | |
5260325f | 1863 | |
7368a6c8 | 1864 | if (c==NULL || c->type != SSH_CHANNEL_OPENING) |
1865 | packet_disconnect("Received open confirmation for " | |
1866 | "non-opening channel %d.", id); | |
1867 | remote_id = packet_get_int(); | |
aa3378df | 1868 | /* Record the remote channel number and mark that the channel is now open. */ |
7368a6c8 | 1869 | c->remote_id = remote_id; |
1870 | c->type = SSH_CHANNEL_OPEN; | |
7e7327a1 | 1871 | |
1872 | if (compat20) { | |
1873 | c->remote_window = packet_get_int(); | |
1874 | c->remote_maxpacket = packet_get_int(); | |
6ae2364d | 1875 | packet_done(); |
7e7327a1 | 1876 | if (c->cb_fn != NULL && c->cb_event == type) { |
de273eef | 1877 | debug2("callback start"); |
7e7327a1 | 1878 | c->cb_fn(c->self, c->cb_arg); |
de273eef | 1879 | debug2("callback done"); |
7e7327a1 | 1880 | } |
1881 | debug("channel %d: open confirm rwindow %d rmax %d", c->self, | |
1882 | c->remote_window, c->remote_maxpacket); | |
1883 | } | |
8efc0c15 | 1884 | } |
1885 | ||
396c147e | 1886 | static char * |
d18e0850 | 1887 | reason2txt(int reason) |
1888 | { | |
1889 | switch(reason) { | |
1890 | case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED: | |
1891 | return "administratively prohibited"; | |
1892 | case SSH2_OPEN_CONNECT_FAILED: | |
1893 | return "connect failed"; | |
1894 | case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE: | |
1895 | return "unknown channel type"; | |
1896 | case SSH2_OPEN_RESOURCE_SHORTAGE: | |
1897 | return "resource shortage"; | |
1898 | } | |
7e8c18e9 | 1899 | return "unknown reason"; |
d18e0850 | 1900 | } |
1901 | ||
6ae2364d | 1902 | void |
188adeb2 | 1903 | channel_input_open_failure(int type, int plen, void *ctxt) |
8efc0c15 | 1904 | { |
02a024dd | 1905 | int id, reason; |
1906 | char *msg = NULL, *lang = NULL; | |
7368a6c8 | 1907 | Channel *c; |
5260325f | 1908 | |
7e7327a1 | 1909 | if (!compat20) |
1910 | packet_integrity_check(plen, 4, type); | |
7368a6c8 | 1911 | |
1912 | id = packet_get_int(); | |
1913 | c = channel_lookup(id); | |
1914 | ||
1915 | if (c==NULL || c->type != SSH_CHANNEL_OPENING) | |
1916 | packet_disconnect("Received open failure for " | |
1917 | "non-opening channel %d.", id); | |
7e7327a1 | 1918 | if (compat20) { |
02a024dd | 1919 | reason = packet_get_int(); |
fbe90f7b | 1920 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { |
02a024dd | 1921 | msg = packet_get_string(NULL); |
1922 | lang = packet_get_string(NULL); | |
1923 | } | |
6ae2364d | 1924 | packet_done(); |
d18e0850 | 1925 | log("channel %d: open failed: %s%s%s", id, |
1926 | reason2txt(reason), msg ? ": ": "", msg ? msg : ""); | |
02a024dd | 1927 | if (msg != NULL) |
1928 | xfree(msg); | |
1929 | if (lang != NULL) | |
1930 | xfree(lang); | |
7e7327a1 | 1931 | } |
5260325f | 1932 | /* Free the channel. This will also close the socket. */ |
719fc62f | 1933 | channel_free(c); |
8efc0c15 | 1934 | } |
1935 | ||
7e7327a1 | 1936 | void |
188adeb2 | 1937 | channel_input_channel_request(int type, int plen, void *ctxt) |
7e7327a1 | 1938 | { |
1939 | int id; | |
1940 | Channel *c; | |
1941 | ||
1942 | id = packet_get_int(); | |
1943 | c = channel_lookup(id); | |
1944 | ||
1945 | if (c == NULL || | |
1946 | (c->type != SSH_CHANNEL_OPEN && c->type != SSH_CHANNEL_LARVAL)) | |
1947 | packet_disconnect("Received request for " | |
1948 | "non-open channel %d.", id); | |
1949 | if (c->cb_fn != NULL && c->cb_event == type) { | |
de273eef | 1950 | debug2("callback start"); |
7e7327a1 | 1951 | c->cb_fn(c->self, c->cb_arg); |
de273eef | 1952 | debug2("callback done"); |
8e7895b8 | 1953 | } else { |
1954 | char *service = packet_get_string(NULL); | |
1955 | debug("channel %d: rcvd request for %s", c->self, service); | |
1956 | debug("cb_fn %p cb_event %d", c->cb_fn , c->cb_event); | |
1957 | xfree(service); | |
719fc62f | 1958 | } |
3ffc6336 | 1959 | } |
1960 | ||
8e7895b8 | 1961 | void |
1962 | channel_input_window_adjust(int type, int plen, void *ctxt) | |
1963 | { | |
1964 | Channel *c; | |
1965 | int id, adjust; | |
3ffc6336 | 1966 | |
8e7895b8 | 1967 | if (!compat20) |
1968 | return; | |
8efc0c15 | 1969 | |
8e7895b8 | 1970 | /* Get the channel number and verify it. */ |
1971 | id = packet_get_int(); | |
1972 | c = channel_lookup(id); | |
1973 | ||
1974 | if (c == NULL || c->type != SSH_CHANNEL_OPEN) { | |
1975 | log("Received window adjust for " | |
1976 | "non-open channel %d.", id); | |
1977 | return; | |
1978 | } | |
1979 | adjust = packet_get_int(); | |
1980 | packet_done(); | |
1981 | debug2("channel %d: rcvd adjust %d", id, adjust); | |
1982 | c->remote_window += adjust; | |
1983 | } | |
1984 | ||
1985 | void | |
1986 | channel_input_port_open(int type, int plen, void *ctxt) | |
8efc0c15 | 1987 | { |
8e7895b8 | 1988 | Channel *c = NULL; |
1989 | u_short host_port; | |
1990 | char *host, *originator_string; | |
1991 | int remote_id, sock = -1; | |
5260325f | 1992 | |
8e7895b8 | 1993 | remote_id = packet_get_int(); |
1994 | host = packet_get_string(NULL); | |
1995 | host_port = packet_get_int(); | |
1996 | ||
1997 | if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) { | |
1998 | originator_string = packet_get_string(NULL); | |
1999 | } else { | |
2000 | originator_string = xstrdup("unknown (remote did not supply name)"); | |
2001 | } | |
2002 | packet_done(); | |
2003 | sock = channel_connect_to(host, host_port); | |
2004 | if (sock != -1) { | |
2005 | c = channel_new("connected socket", | |
2006 | SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0, | |
2007 | originator_string, 1); | |
2008 | if (c == NULL) { | |
2009 | error("channel_input_port_open: channel_new failed"); | |
2010 | close(sock); | |
2011 | } else { | |
2012 | c->remote_id = remote_id; | |
5260325f | 2013 | } |
2014 | } | |
8e7895b8 | 2015 | if (c == NULL) { |
2016 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
2017 | packet_put_int(remote_id); | |
2018 | packet_send(); | |
2019 | } | |
2020 | xfree(host); | |
8efc0c15 | 2021 | } |
2022 | ||
8e7895b8 | 2023 | |
2024 | /* -- tcp forwarding */ | |
2025 | ||
aa3378df | 2026 | /* |
2027 | * Initiate forwarding of connections to local port "port" through the secure | |
2028 | * channel to host:port from remote side. | |
2029 | */ | |
02a024dd | 2030 | int |
fa08c86b | 2031 | channel_request_local_forwarding(u_short listen_port, const char *host_to_connect, |
2032 | u_short port_to_connect, int gateway_ports) | |
2033 | { | |
02a024dd | 2034 | return channel_request_forwarding( |
fa08c86b | 2035 | NULL, listen_port, |
2036 | host_to_connect, port_to_connect, | |
2037 | gateway_ports, /*remote_fwd*/ 0); | |
2038 | } | |
8efc0c15 | 2039 | |
fa08c86b | 2040 | /* |
2041 | * If 'remote_fwd' is true we have a '-R style' listener for protocol 2 | |
2042 | * (SSH_CHANNEL_RPORT_LISTENER). | |
2043 | */ | |
02a024dd | 2044 | int |
fa08c86b | 2045 | channel_request_forwarding( |
2046 | const char *listen_address, u_short listen_port, | |
2047 | const char *host_to_connect, u_short port_to_connect, | |
2048 | int gateway_ports, int remote_fwd) | |
8efc0c15 | 2049 | { |
719fc62f | 2050 | Channel *c; |
8e7895b8 | 2051 | int success, sock, on = 1, type; |
48e671d5 | 2052 | struct addrinfo hints, *ai, *aitop; |
2053 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; | |
fa08c86b | 2054 | const char *host; |
aa3378df | 2055 | struct linger linger; |
5260325f | 2056 | |
02a024dd | 2057 | success = 0; |
2058 | ||
fa08c86b | 2059 | if (remote_fwd) { |
2060 | host = listen_address; | |
8e7895b8 | 2061 | type = SSH_CHANNEL_RPORT_LISTENER; |
fa08c86b | 2062 | } else { |
2063 | host = host_to_connect; | |
8e7895b8 | 2064 | type = SSH_CHANNEL_PORT_LISTENER; |
fa08c86b | 2065 | } |
2066 | ||
719fc62f | 2067 | if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) { |
02a024dd | 2068 | error("Forward host name too long."); |
2069 | return success; | |
2070 | } | |
5260325f | 2071 | |
fa08c86b | 2072 | /* XXX listen_address is currently ignored */ |
aa3378df | 2073 | /* |
48e671d5 | 2074 | * getaddrinfo returns a loopback address if the hostname is |
2075 | * set to NULL and hints.ai_flags is not AI_PASSIVE | |
aa3378df | 2076 | */ |
48e671d5 | 2077 | memset(&hints, 0, sizeof(hints)); |
2078 | hints.ai_family = IPv4or6; | |
2079 | hints.ai_flags = gateway_ports ? AI_PASSIVE : 0; | |
2080 | hints.ai_socktype = SOCK_STREAM; | |
fa08c86b | 2081 | snprintf(strport, sizeof strport, "%d", listen_port); |
48e671d5 | 2082 | if (getaddrinfo(NULL, strport, &hints, &aitop) != 0) |
2083 | packet_disconnect("getaddrinfo: fatal error"); | |
2084 | ||
48e671d5 | 2085 | for (ai = aitop; ai; ai = ai->ai_next) { |
2086 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2087 | continue; | |
2088 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), | |
2089 | strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
fa08c86b | 2090 | error("channel_request_forwarding: getnameinfo failed"); |
48e671d5 | 2091 | continue; |
2092 | } | |
2093 | /* Create a port to listen for the host. */ | |
2094 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
2095 | if (sock < 0) { | |
2096 | /* this is no error since kernel may not support ipv6 */ | |
2097 | verbose("socket: %.100s", strerror(errno)); | |
2098 | continue; | |
2099 | } | |
2100 | /* | |
2101 | * Set socket options. We would like the socket to disappear | |
2102 | * as soon as it has been closed for whatever reason. | |
2103 | */ | |
2104 | setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on)); | |
2105 | linger.l_onoff = 1; | |
2106 | linger.l_linger = 5; | |
2107 | setsockopt(sock, SOL_SOCKET, SO_LINGER, (void *)&linger, sizeof(linger)); | |
2108 | debug("Local forwarding listening on %s port %s.", ntop, strport); | |
2109 | ||
2110 | /* Bind the socket to the address. */ | |
2111 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
2112 | /* address can be in use ipv6 address is already bound */ | |
16218745 | 2113 | if (!ai->ai_next) |
2114 | error("bind: %.100s", strerror(errno)); | |
2115 | else | |
2116 | verbose("bind: %.100s", strerror(errno)); | |
2b87da3b | 2117 | |
48e671d5 | 2118 | close(sock); |
2119 | continue; | |
2120 | } | |
2121 | /* Start listening for connections on the socket. */ | |
2122 | if (listen(sock, 5) < 0) { | |
2123 | error("listen: %.100s", strerror(errno)); | |
2124 | close(sock); | |
2125 | continue; | |
2126 | } | |
2127 | /* Allocate a channel number for the socket. */ | |
8e7895b8 | 2128 | c = channel_new("port listener", type, sock, sock, -1, |
0b242b12 | 2129 | CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, |
a22aff1f | 2130 | 0, xstrdup("port listener"), 1); |
719fc62f | 2131 | if (c == NULL) { |
2132 | error("channel_request_forwarding: channel_new failed"); | |
2133 | close(sock); | |
2134 | continue; | |
2135 | } | |
2136 | strlcpy(c->path, host, sizeof(c->path)); | |
2137 | c->host_port = port_to_connect; | |
2138 | c->listening_port = listen_port; | |
48e671d5 | 2139 | success = 1; |
2140 | } | |
2141 | if (success == 0) | |
02a024dd | 2142 | error("channel_request_forwarding: cannot listen to port: %d", |
2143 | listen_port); | |
48e671d5 | 2144 | freeaddrinfo(aitop); |
02a024dd | 2145 | return success; |
5260325f | 2146 | } |
8efc0c15 | 2147 | |
aa3378df | 2148 | /* |
2149 | * Initiate forwarding of connections to port "port" on remote host through | |
2150 | * the secure channel to host:port from local side. | |
2151 | */ | |
8efc0c15 | 2152 | |
6ae2364d | 2153 | void |
fa08c86b | 2154 | channel_request_remote_forwarding(u_short listen_port, |
2155 | const char *host_to_connect, u_short port_to_connect) | |
8efc0c15 | 2156 | { |
fa08c86b | 2157 | int payload_len, type, success = 0; |
2158 | ||
5260325f | 2159 | /* Record locally that connection to this host/port is permitted. */ |
2160 | if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION) | |
2161 | fatal("channel_request_remote_forwarding: too many forwards"); | |
2162 | ||
5260325f | 2163 | /* Send the forward request to the remote side. */ |
7e7327a1 | 2164 | if (compat20) { |
2165 | const char *address_to_bind = "0.0.0.0"; | |
2166 | packet_start(SSH2_MSG_GLOBAL_REQUEST); | |
2167 | packet_put_cstring("tcpip-forward"); | |
2168 | packet_put_char(0); /* boolean: want reply */ | |
2169 | packet_put_cstring(address_to_bind); | |
2170 | packet_put_int(listen_port); | |
fa08c86b | 2171 | packet_send(); |
2172 | packet_write_wait(); | |
2173 | /* Assume that server accepts the request */ | |
2174 | success = 1; | |
7e7327a1 | 2175 | } else { |
2176 | packet_start(SSH_CMSG_PORT_FORWARD_REQUEST); | |
7e7327a1 | 2177 | packet_put_int(listen_port); |
d6f24e45 | 2178 | packet_put_cstring(host_to_connect); |
2179 | packet_put_int(port_to_connect); | |
7e7327a1 | 2180 | packet_send(); |
2181 | packet_write_wait(); | |
fa08c86b | 2182 | |
2183 | /* Wait for response from the remote side. */ | |
2184 | type = packet_read(&payload_len); | |
2185 | switch (type) { | |
2186 | case SSH_SMSG_SUCCESS: | |
2187 | success = 1; | |
2188 | break; | |
2189 | case SSH_SMSG_FAILURE: | |
2190 | log("Warning: Server denied remote port forwarding."); | |
2191 | break; | |
2192 | default: | |
2193 | /* Unknown packet */ | |
2194 | packet_disconnect("Protocol error for port forward request:" | |
2195 | "received packet type %d.", type); | |
2196 | } | |
2197 | } | |
2198 | if (success) { | |
2199 | permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect); | |
2200 | permitted_opens[num_permitted_opens].port_to_connect = port_to_connect; | |
2201 | permitted_opens[num_permitted_opens].listen_port = listen_port; | |
2202 | num_permitted_opens++; | |
7e7327a1 | 2203 | } |
8efc0c15 | 2204 | } |
2205 | ||
aa3378df | 2206 | /* |
2207 | * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates | |
2208 | * listening for the port, and sends back a success reply (or disconnect | |
2209 | * message if there was an error). This never returns if there was an error. | |
2210 | */ | |
8efc0c15 | 2211 | |
6ae2364d | 2212 | void |
1d1ffb87 | 2213 | channel_input_port_forward_request(int is_root, int gateway_ports) |
8efc0c15 | 2214 | { |
57112b5a | 2215 | u_short port, host_port; |
5260325f | 2216 | char *hostname; |
2217 | ||
2218 | /* Get arguments from the packet. */ | |
2219 | port = packet_get_int(); | |
2220 | hostname = packet_get_string(NULL); | |
2221 | host_port = packet_get_int(); | |
2222 | ||
3c62e7eb | 2223 | #ifndef HAVE_CYGWIN |
aa3378df | 2224 | /* |
2225 | * Check that an unprivileged user is not trying to forward a | |
2226 | * privileged port. | |
2227 | */ | |
5260325f | 2228 | if (port < IPPORT_RESERVED && !is_root) |
2229 | packet_disconnect("Requested forwarding of port %d but user is not root.", | |
2230 | port); | |
3c62e7eb | 2231 | #endif |
fa08c86b | 2232 | /* Initiate forwarding */ |
1d1ffb87 | 2233 | channel_request_local_forwarding(port, hostname, host_port, gateway_ports); |
5260325f | 2234 | |
2235 | /* Free the argument string. */ | |
2236 | xfree(hostname); | |
8efc0c15 | 2237 | } |
2238 | ||
01794848 | 2239 | /* |
2240 | * Permits opening to any host/port if permitted_opens[] is empty. This is | |
2241 | * usually called by the server, because the user could connect to any port | |
2242 | * anyway, and the server has no way to know but to trust the client anyway. | |
2243 | */ | |
2244 | void | |
2245 | channel_permit_all_opens() | |
2246 | { | |
2247 | if (num_permitted_opens == 0) | |
2248 | all_opens_permitted = 1; | |
2249 | } | |
2250 | ||
cd332296 | 2251 | void |
01794848 | 2252 | channel_add_permitted_opens(char *host, int port) |
2253 | { | |
2254 | if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION) | |
2255 | fatal("channel_request_remote_forwarding: too many forwards"); | |
2256 | debug("allow port forwarding to host %s port %d", host, port); | |
2257 | ||
2258 | permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host); | |
2259 | permitted_opens[num_permitted_opens].port_to_connect = port; | |
2260 | num_permitted_opens++; | |
2261 | ||
2262 | all_opens_permitted = 0; | |
2263 | } | |
2264 | ||
cd332296 | 2265 | void |
01794848 | 2266 | channel_clear_permitted_opens(void) |
2267 | { | |
2268 | int i; | |
2269 | ||
2270 | for (i = 0; i < num_permitted_opens; i++) | |
2271 | xfree(permitted_opens[i].host_to_connect); | |
2272 | num_permitted_opens = 0; | |
2273 | ||
2274 | } | |
2275 | ||
2276 | ||
2277 | /* return socket to remote host, port */ | |
396c147e | 2278 | static int |
01794848 | 2279 | connect_to(const char *host, u_short port) |
8efc0c15 | 2280 | { |
48e671d5 | 2281 | struct addrinfo hints, *ai, *aitop; |
2282 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; | |
2283 | int gaierr; | |
7368a6c8 | 2284 | int sock = -1; |
48e671d5 | 2285 | |
2286 | memset(&hints, 0, sizeof(hints)); | |
2287 | hints.ai_family = IPv4or6; | |
2288 | hints.ai_socktype = SOCK_STREAM; | |
01794848 | 2289 | snprintf(strport, sizeof strport, "%d", port); |
48e671d5 | 2290 | if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) { |
01794848 | 2291 | error("connect_to %.100s: unknown host (%s)", host, |
2292 | gai_strerror(gaierr)); | |
7368a6c8 | 2293 | return -1; |
48e671d5 | 2294 | } |
48e671d5 | 2295 | for (ai = aitop; ai; ai = ai->ai_next) { |
2296 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2297 | continue; | |
2298 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), | |
2299 | strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
01794848 | 2300 | error("connect_to: getnameinfo failed"); |
48e671d5 | 2301 | continue; |
5260325f | 2302 | } |
48e671d5 | 2303 | sock = socket(ai->ai_family, SOCK_STREAM, 0); |
2304 | if (sock < 0) { | |
2305 | error("socket: %.100s", strerror(errno)); | |
2306 | continue; | |
5260325f | 2307 | } |
eea39c02 | 2308 | if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0) |
97fb6912 | 2309 | fatal("connect_to: F_SETFL: %s", strerror(errno)); |
97fb6912 | 2310 | if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 && |
2311 | errno != EINPROGRESS) { | |
01794848 | 2312 | error("connect_to %.100s port %s: %.100s", ntop, strport, |
48e671d5 | 2313 | strerror(errno)); |
2314 | close(sock); | |
2b87da3b | 2315 | continue; /* fail -- try next */ |
48e671d5 | 2316 | } |
2317 | break; /* success */ | |
5260325f | 2318 | |
5260325f | 2319 | } |
48e671d5 | 2320 | freeaddrinfo(aitop); |
48e671d5 | 2321 | if (!ai) { |
01794848 | 2322 | error("connect_to %.100s port %d: failed.", host, port); |
7368a6c8 | 2323 | return -1; |
8efc0c15 | 2324 | } |
7368a6c8 | 2325 | /* success */ |
2326 | return sock; | |
2327 | } | |
01794848 | 2328 | |
fa08c86b | 2329 | int |
b3f8a79c | 2330 | channel_connect_by_listen_address(u_short listen_port) |
fa08c86b | 2331 | { |
2332 | int i; | |
01794848 | 2333 | |
fa08c86b | 2334 | for (i = 0; i < num_permitted_opens; i++) |
2335 | if (permitted_opens[i].listen_port == listen_port) | |
01794848 | 2336 | return connect_to( |
fa08c86b | 2337 | permitted_opens[i].host_to_connect, |
2338 | permitted_opens[i].port_to_connect); | |
0b6fbf03 | 2339 | error("WARNING: Server requests forwarding for unknown listen_port %d", |
2340 | listen_port); | |
fa08c86b | 2341 | return -1; |
2342 | } | |
48e671d5 | 2343 | |
01794848 | 2344 | /* Check if connecting to that port is permitted and connect. */ |
2345 | int | |
2346 | channel_connect_to(const char *host, u_short port) | |
2347 | { | |
2348 | int i, permit; | |
2349 | ||
2350 | permit = all_opens_permitted; | |
2351 | if (!permit) { | |
2352 | for (i = 0; i < num_permitted_opens; i++) | |
2353 | if (permitted_opens[i].port_to_connect == port && | |
2354 | strcmp(permitted_opens[i].host_to_connect, host) == 0) | |
2355 | permit = 1; | |
2356 | ||
2357 | } | |
2358 | if (!permit) { | |
2359 | log("Received request to connect to host %.100s port %d, " | |
2360 | "but the request was denied.", host, port); | |
2361 | return -1; | |
2362 | } | |
2363 | return connect_to(host, port); | |
2364 | } | |
2365 | ||
8e7895b8 | 2366 | /* -- X11 forwarding */ |
8efc0c15 | 2367 | |
aa3378df | 2368 | /* |
2369 | * Creates an internet domain socket for listening for X11 connections. | |
2370 | * Returns a suitable value for the DISPLAY variable, or NULL if an error | |
2371 | * occurs. | |
2372 | */ | |
5260325f | 2373 | char * |
95f1eccc | 2374 | x11_create_display_inet(int screen_number, int x11_display_offset) |
8efc0c15 | 2375 | { |
57112b5a | 2376 | int display_number, sock; |
2377 | u_short port; | |
48e671d5 | 2378 | struct addrinfo hints, *ai, *aitop; |
2379 | char strport[NI_MAXSERV]; | |
2380 | int gaierr, n, num_socks = 0, socks[NUM_SOCKS]; | |
2381 | char display[512]; | |
5260325f | 2382 | char hostname[MAXHOSTNAMELEN]; |
2383 | ||
95f1eccc | 2384 | for (display_number = x11_display_offset; |
5260325f | 2385 | display_number < MAX_DISPLAYS; |
2386 | display_number++) { | |
2387 | port = 6000 + display_number; | |
48e671d5 | 2388 | memset(&hints, 0, sizeof(hints)); |
2389 | hints.ai_family = IPv4or6; | |
2390 | hints.ai_flags = AI_PASSIVE; /* XXX loopback only ? */ | |
2391 | hints.ai_socktype = SOCK_STREAM; | |
2392 | snprintf(strport, sizeof strport, "%d", port); | |
2393 | if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) { | |
2394 | error("getaddrinfo: %.100s", gai_strerror(gaierr)); | |
5260325f | 2395 | return NULL; |
2396 | } | |
48e671d5 | 2397 | for (ai = aitop; ai; ai = ai->ai_next) { |
2398 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2399 | continue; | |
2400 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
2401 | if (sock < 0) { | |
4ee81249 | 2402 | if ((errno != EINVAL) && (errno != EAFNOSUPPORT)) { |
80a44451 | 2403 | error("socket: %.100s", strerror(errno)); |
2404 | return NULL; | |
2405 | } else { | |
22d89d24 | 2406 | debug("x11_create_display_inet: Socket family %d not supported", |
2407 | ai->ai_family); | |
80a44451 | 2408 | continue; |
2409 | } | |
48e671d5 | 2410 | } |
2411 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
2412 | debug("bind port %d: %.100s", port, strerror(errno)); | |
2413 | shutdown(sock, SHUT_RDWR); | |
2414 | close(sock); | |
16218745 | 2415 | |
2416 | if (ai->ai_next) | |
2417 | continue; | |
2418 | ||
48e671d5 | 2419 | for (n = 0; n < num_socks; n++) { |
2420 | shutdown(socks[n], SHUT_RDWR); | |
2421 | close(socks[n]); | |
2422 | } | |
2423 | num_socks = 0; | |
2424 | break; | |
2425 | } | |
2426 | socks[num_socks++] = sock; | |
80faa19f | 2427 | #ifndef DONT_TRY_OTHER_AF |
48e671d5 | 2428 | if (num_socks == NUM_SOCKS) |
2429 | break; | |
80faa19f | 2430 | #else |
2431 | break; | |
2432 | #endif | |
5260325f | 2433 | } |
4ccb01d6 | 2434 | freeaddrinfo(aitop); |
48e671d5 | 2435 | if (num_socks > 0) |
2436 | break; | |
5260325f | 2437 | } |
2438 | if (display_number >= MAX_DISPLAYS) { | |
2439 | error("Failed to allocate internet-domain X11 display socket."); | |
2440 | return NULL; | |
8efc0c15 | 2441 | } |
5260325f | 2442 | /* Start listening for connections on the socket. */ |
48e671d5 | 2443 | for (n = 0; n < num_socks; n++) { |
2444 | sock = socks[n]; | |
2445 | if (listen(sock, 5) < 0) { | |
2446 | error("listen: %.100s", strerror(errno)); | |
2447 | shutdown(sock, SHUT_RDWR); | |
2448 | close(sock); | |
2449 | return NULL; | |
2450 | } | |
8efc0c15 | 2451 | } |
48e671d5 | 2452 | |
5260325f | 2453 | /* Set up a suitable value for the DISPLAY variable. */ |
2454 | if (gethostname(hostname, sizeof(hostname)) < 0) | |
2455 | fatal("gethostname: %.100s", strerror(errno)); | |
a7effaac | 2456 | |
2457 | #ifdef IPADDR_IN_DISPLAY | |
2b87da3b | 2458 | /* |
a7effaac | 2459 | * HPUX detects the local hostname in the DISPLAY variable and tries |
2460 | * to set up a shared memory connection to the server, which it | |
2461 | * incorrectly supposes to be local. | |
2462 | * | |
2463 | * The workaround - as used in later $$H and other programs - is | |
2464 | * is to set display to the host's IP address. | |
2465 | */ | |
2466 | { | |
2467 | struct hostent *he; | |
2468 | struct in_addr my_addr; | |
2469 | ||
2470 | he = gethostbyname(hostname); | |
2471 | if (he == NULL) { | |
2472 | error("[X11-broken-fwd-hostname-workaround] Could not get " | |
2473 | "IP address for hostname %s.", hostname); | |
2474 | ||
2475 | packet_send_debug("[X11-broken-fwd-hostname-workaround]" | |
2476 | "Could not get IP address for hostname %s.", hostname); | |
2477 | ||
2478 | shutdown(sock, SHUT_RDWR); | |
2479 | close(sock); | |
2480 | ||
2481 | return NULL; | |
2482 | } | |
2483 | ||
2484 | memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr)); | |
2485 | ||
2486 | /* Set DISPLAY to <ip address>:screen.display */ | |
2b87da3b | 2487 | snprintf(display, sizeof(display), "%.50s:%d.%d", inet_ntoa(my_addr), |
74141647 | 2488 | display_number, screen_number); |
a7effaac | 2489 | } |
2490 | #else /* IPADDR_IN_DISPLAY */ | |
2491 | /* Just set DISPLAY to hostname:screen.display */ | |
48e671d5 | 2492 | snprintf(display, sizeof display, "%.400s:%d.%d", hostname, |
74141647 | 2493 | display_number, screen_number); |
a7effaac | 2494 | #endif /* IPADDR_IN_DISPLAY */ |
5260325f | 2495 | |
48e671d5 | 2496 | /* Allocate a channel for each socket. */ |
2497 | for (n = 0; n < num_socks; n++) { | |
2498 | sock = socks[n]; | |
0b242b12 | 2499 | (void) channel_new("x11 listener", |
2500 | SSH_CHANNEL_X11_LISTENER, sock, sock, -1, | |
2501 | CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, | |
a22aff1f | 2502 | 0, xstrdup("X11 inet listener"), 1); |
48e671d5 | 2503 | } |
5260325f | 2504 | |
2505 | /* Return a suitable value for the DISPLAY environment variable. */ | |
48e671d5 | 2506 | return xstrdup(display); |
8efc0c15 | 2507 | } |
2508 | ||
2509 | #ifndef X_UNIX_PATH | |
2510 | #define X_UNIX_PATH "/tmp/.X11-unix/X" | |
2511 | #endif | |
2512 | ||
396c147e | 2513 | static int |
1e3b8b07 | 2514 | connect_local_xsocket(u_int dnr) |
8efc0c15 | 2515 | { |
5260325f | 2516 | static const char *const x_sockets[] = { |
2517 | X_UNIX_PATH "%u", | |
2518 | "/var/X/.X11-unix/X" "%u", | |
2519 | "/usr/spool/sockets/X11/" "%u", | |
2520 | NULL | |
2521 | }; | |
2522 | int sock; | |
2523 | struct sockaddr_un addr; | |
2524 | const char *const * path; | |
2525 | ||
2526 | for (path = x_sockets; *path; ++path) { | |
2527 | sock = socket(AF_UNIX, SOCK_STREAM, 0); | |
2528 | if (sock < 0) | |
2529 | error("socket: %.100s", strerror(errno)); | |
2530 | memset(&addr, 0, sizeof(addr)); | |
2531 | addr.sun_family = AF_UNIX; | |
2532 | snprintf(addr.sun_path, sizeof addr.sun_path, *path, dnr); | |
2533 | if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0) | |
2534 | return sock; | |
2535 | close(sock); | |
2536 | } | |
2537 | error("connect %.100s: %.100s", addr.sun_path, strerror(errno)); | |
2538 | return -1; | |
8efc0c15 | 2539 | } |
2540 | ||
0b242b12 | 2541 | int |
2542 | x11_connect_display(void) | |
8efc0c15 | 2543 | { |
0b242b12 | 2544 | int display_number, sock = 0; |
5260325f | 2545 | const char *display; |
0b242b12 | 2546 | char buf[1024], *cp; |
48e671d5 | 2547 | struct addrinfo hints, *ai, *aitop; |
2548 | char strport[NI_MAXSERV]; | |
2549 | int gaierr; | |
5260325f | 2550 | |
5260325f | 2551 | /* Try to open a socket for the local X server. */ |
2552 | display = getenv("DISPLAY"); | |
2553 | if (!display) { | |
2554 | error("DISPLAY not set."); | |
0b242b12 | 2555 | return -1; |
5260325f | 2556 | } |
aa3378df | 2557 | /* |
2558 | * Now we decode the value of the DISPLAY variable and make a | |
2559 | * connection to the real X server. | |
2560 | */ | |
2561 | ||
2562 | /* | |
2563 | * Check if it is a unix domain socket. Unix domain displays are in | |
2564 | * one of the following formats: unix:d[.s], :d[.s], ::d[.s] | |
2565 | */ | |
5260325f | 2566 | if (strncmp(display, "unix:", 5) == 0 || |
2567 | display[0] == ':') { | |
2568 | /* Connect to the unix domain socket. */ | |
2569 | if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) { | |
2570 | error("Could not parse display number from DISPLAY: %.100s", | |
2571 | display); | |
0b242b12 | 2572 | return -1; |
5260325f | 2573 | } |
2574 | /* Create a socket. */ | |
2575 | sock = connect_local_xsocket(display_number); | |
2576 | if (sock < 0) | |
0b242b12 | 2577 | return -1; |
5260325f | 2578 | |
2579 | /* OK, we now have a connection to the display. */ | |
0b242b12 | 2580 | return sock; |
5260325f | 2581 | } |
aa3378df | 2582 | /* |
2583 | * Connect to an inet socket. The DISPLAY value is supposedly | |
2584 | * hostname:d[.s], where hostname may also be numeric IP address. | |
2585 | */ | |
5260325f | 2586 | strncpy(buf, display, sizeof(buf)); |
2587 | buf[sizeof(buf) - 1] = 0; | |
2588 | cp = strchr(buf, ':'); | |
2589 | if (!cp) { | |
2590 | error("Could not find ':' in DISPLAY: %.100s", display); | |
0b242b12 | 2591 | return -1; |
5260325f | 2592 | } |
2593 | *cp = 0; | |
aa3378df | 2594 | /* buf now contains the host name. But first we parse the display number. */ |
5260325f | 2595 | if (sscanf(cp + 1, "%d", &display_number) != 1) { |
2596 | error("Could not parse display number from DISPLAY: %.100s", | |
2597 | display); | |
0b242b12 | 2598 | return -1; |
5260325f | 2599 | } |
5260325f | 2600 | |
48e671d5 | 2601 | /* Look up the host address */ |
2602 | memset(&hints, 0, sizeof(hints)); | |
2603 | hints.ai_family = IPv4or6; | |
2604 | hints.ai_socktype = SOCK_STREAM; | |
2605 | snprintf(strport, sizeof strport, "%d", 6000 + display_number); | |
2606 | if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) { | |
2607 | error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr)); | |
0b242b12 | 2608 | return -1; |
8efc0c15 | 2609 | } |
48e671d5 | 2610 | for (ai = aitop; ai; ai = ai->ai_next) { |
2611 | /* Create a socket. */ | |
2612 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
2613 | if (sock < 0) { | |
2614 | debug("socket: %.100s", strerror(errno)); | |
7368a6c8 | 2615 | continue; |
2616 | } | |
2617 | /* Connect it to the display. */ | |
2618 | if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
2619 | debug("connect %.100s port %d: %.100s", buf, | |
2620 | 6000 + display_number, strerror(errno)); | |
2621 | close(sock); | |
2622 | continue; | |
2623 | } | |
2624 | /* Success */ | |
2625 | break; | |
48e671d5 | 2626 | } |
48e671d5 | 2627 | freeaddrinfo(aitop); |
2628 | if (!ai) { | |
6ae2364d | 2629 | error("connect %.100s port %d: %.100s", buf, 6000 + display_number, |
48e671d5 | 2630 | strerror(errno)); |
0b242b12 | 2631 | return -1; |
8efc0c15 | 2632 | } |
0b242b12 | 2633 | return sock; |
2634 | } | |
5260325f | 2635 | |
0b242b12 | 2636 | /* |
2637 | * This is called when SSH_SMSG_X11_OPEN is received. The packet contains | |
2638 | * the remote channel number. We should do whatever we want, and respond | |
2639 | * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE. | |
2640 | */ | |
5260325f | 2641 | |
0b242b12 | 2642 | void |
188adeb2 | 2643 | x11_input_open(int type, int plen, void *ctxt) |
0b242b12 | 2644 | { |
719fc62f | 2645 | Channel *c = NULL; |
2646 | int remote_id, sock = 0; | |
0b242b12 | 2647 | char *remote_host; |
5260325f | 2648 | |
719fc62f | 2649 | debug("Received X11 open request."); |
5260325f | 2650 | |
719fc62f | 2651 | remote_id = packet_get_int(); |
8e7895b8 | 2652 | |
2653 | if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) { | |
719fc62f | 2654 | remote_host = packet_get_string(NULL); |
0b242b12 | 2655 | } else { |
2656 | remote_host = xstrdup("unknown (remote did not supply name)"); | |
0b242b12 | 2657 | } |
719fc62f | 2658 | packet_done(); |
0b242b12 | 2659 | |
2660 | /* Obtain a connection to the real X display. */ | |
2661 | sock = x11_connect_display(); | |
719fc62f | 2662 | if (sock != -1) { |
2663 | /* Allocate a channel for this connection. */ | |
2664 | c = channel_new("connected x11 socket", | |
2665 | SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0, | |
2666 | remote_host, 1); | |
2667 | if (c == NULL) { | |
2668 | error("x11_input_open: channel_new failed"); | |
2669 | close(sock); | |
2670 | } else { | |
2671 | c->remote_id = remote_id; | |
2672 | } | |
2673 | } | |
2674 | if (c == NULL) { | |
0b242b12 | 2675 | /* Send refusal to the remote host. */ |
2676 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
719fc62f | 2677 | packet_put_int(remote_id); |
0b242b12 | 2678 | } else { |
0b242b12 | 2679 | /* Send a confirmation to the remote host. */ |
2680 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
719fc62f | 2681 | packet_put_int(remote_id); |
2682 | packet_put_int(c->self); | |
0b242b12 | 2683 | } |
719fc62f | 2684 | packet_send(); |
8efc0c15 | 2685 | } |
2686 | ||
a22aff1f | 2687 | /* dummy protocol handler that denies SSH-1 requests (agent/x11) */ |
2688 | void | |
2689 | deny_input_open(int type, int plen, void *ctxt) | |
2690 | { | |
2691 | int rchan = packet_get_int(); | |
2692 | switch(type){ | |
2693 | case SSH_SMSG_AGENT_OPEN: | |
2694 | error("Warning: ssh server tried agent forwarding."); | |
2695 | break; | |
2696 | case SSH_SMSG_X11_OPEN: | |
2697 | error("Warning: ssh server tried X11 forwarding."); | |
2698 | break; | |
2699 | default: | |
2700 | error("deny_input_open: type %d plen %d", type, plen); | |
2701 | break; | |
2702 | } | |
2703 | error("Warning: this is probably a break in attempt by a malicious server."); | |
2704 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
2705 | packet_put_int(rchan); | |
2706 | packet_send(); | |
2707 | } | |
2708 | ||
aa3378df | 2709 | /* |
2710 | * Requests forwarding of X11 connections, generates fake authentication | |
2711 | * data, and enables authentication spoofing. | |
8e7895b8 | 2712 | * This should be called in the client only. |
aa3378df | 2713 | */ |
6ae2364d | 2714 | void |
0b242b12 | 2715 | x11_request_forwarding_with_spoofing(int client_session_id, |
2716 | const char *proto, const char *data) | |
8efc0c15 | 2717 | { |
1e3b8b07 | 2718 | u_int data_len = (u_int) strlen(data) / 2; |
ca910e13 | 2719 | u_int i, value, len; |
5260325f | 2720 | char *new_data; |
2721 | int screen_number; | |
2722 | const char *cp; | |
2723 | u_int32_t rand = 0; | |
2724 | ||
2725 | cp = getenv("DISPLAY"); | |
2726 | if (cp) | |
2727 | cp = strchr(cp, ':'); | |
2728 | if (cp) | |
2729 | cp = strchr(cp, '.'); | |
2730 | if (cp) | |
2731 | screen_number = atoi(cp + 1); | |
2732 | else | |
2733 | screen_number = 0; | |
2734 | ||
2735 | /* Save protocol name. */ | |
2736 | x11_saved_proto = xstrdup(proto); | |
2737 | ||
aa3378df | 2738 | /* |
2739 | * Extract real authentication data and generate fake data of the | |
2740 | * same length. | |
2741 | */ | |
5260325f | 2742 | x11_saved_data = xmalloc(data_len); |
2743 | x11_fake_data = xmalloc(data_len); | |
2744 | for (i = 0; i < data_len; i++) { | |
2745 | if (sscanf(data + 2 * i, "%2x", &value) != 1) | |
2746 | fatal("x11_request_forwarding: bad authentication data: %.100s", data); | |
2747 | if (i % 4 == 0) | |
2748 | rand = arc4random(); | |
2749 | x11_saved_data[i] = value; | |
2750 | x11_fake_data[i] = rand & 0xff; | |
2751 | rand >>= 8; | |
2752 | } | |
2753 | x11_saved_data_len = data_len; | |
2754 | x11_fake_data_len = data_len; | |
2755 | ||
2756 | /* Convert the fake data into hex. */ | |
ca910e13 | 2757 | len = 2 * data_len + 1; |
2758 | new_data = xmalloc(len); | |
5260325f | 2759 | for (i = 0; i < data_len; i++) |
ca910e13 | 2760 | snprintf(new_data + 2 * i, len - 2 * i, |
2761 | "%02x", (u_char) x11_fake_data[i]); | |
5260325f | 2762 | |
2763 | /* Send the request packet. */ | |
0b242b12 | 2764 | if (compat20) { |
2765 | channel_request_start(client_session_id, "x11-req", 0); | |
2766 | packet_put_char(0); /* XXX bool single connection */ | |
2767 | } else { | |
2768 | packet_start(SSH_CMSG_X11_REQUEST_FORWARDING); | |
2769 | } | |
2770 | packet_put_cstring(proto); | |
2771 | packet_put_cstring(new_data); | |
5260325f | 2772 | packet_put_int(screen_number); |
2773 | packet_send(); | |
2774 | packet_write_wait(); | |
2775 | xfree(new_data); | |
8efc0c15 | 2776 | } |
2777 | ||
8e7895b8 | 2778 | |
2779 | /* -- agent forwarding */ | |
2780 | ||
8efc0c15 | 2781 | /* Sends a message to the server to request authentication fd forwarding. */ |
2782 | ||
6ae2364d | 2783 | void |
5260325f | 2784 | auth_request_forwarding() |
8efc0c15 | 2785 | { |
5260325f | 2786 | packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING); |
2787 | packet_send(); | |
2788 | packet_write_wait(); | |
8efc0c15 | 2789 | } |
2790 | ||
aa3378df | 2791 | /* |
2792 | * Returns the name of the forwarded authentication socket. Returns NULL if | |
2793 | * there is no forwarded authentication socket. The returned value points to | |
2794 | * a static buffer. | |
2795 | */ | |
8efc0c15 | 2796 | |
5260325f | 2797 | char * |
2798 | auth_get_socket_name() | |
8efc0c15 | 2799 | { |
8e7895b8 | 2800 | return auth_sock_name; |
8efc0c15 | 2801 | } |
2802 | ||
2803 | /* removes the agent forwarding socket */ | |
2804 | ||
6ae2364d | 2805 | void |
f0f32b8e | 2806 | auth_sock_cleanup_proc(void *_pw) |
5260325f | 2807 | { |
f0f32b8e | 2808 | struct passwd *pw = _pw; |
2809 | ||
e4f7282d | 2810 | if (auth_sock_name) { |
f0f32b8e | 2811 | temporarily_use_uid(pw); |
e4f7282d | 2812 | unlink(auth_sock_name); |
2813 | rmdir(auth_sock_dir); | |
2814 | auth_sock_name = NULL; | |
f0f32b8e | 2815 | restore_uid(); |
e4f7282d | 2816 | } |
8efc0c15 | 2817 | } |
2818 | ||
aa3378df | 2819 | /* |
fa649821 | 2820 | * This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server. |
aa3378df | 2821 | * This starts forwarding authentication requests. |
2822 | */ | |
8efc0c15 | 2823 | |
fa649821 | 2824 | int |
5260325f | 2825 | auth_input_request_forwarding(struct passwd * pw) |
8efc0c15 | 2826 | { |
719fc62f | 2827 | Channel *nc; |
2828 | int sock; | |
5260325f | 2829 | struct sockaddr_un sunaddr; |
2830 | ||
8e7895b8 | 2831 | if (auth_get_socket_name() != NULL) { |
2832 | error("authentication forwarding requested twice."); | |
2833 | return 0; | |
2834 | } | |
5260325f | 2835 | |
2836 | /* Temporarily drop privileged uid for mkdir/bind. */ | |
63bd8c36 | 2837 | temporarily_use_uid(pw); |
5260325f | 2838 | |
2839 | /* Allocate a buffer for the socket name, and format the name. */ | |
8e7895b8 | 2840 | auth_sock_name = xmalloc(MAXPATHLEN); |
2841 | auth_sock_dir = xmalloc(MAXPATHLEN); | |
2842 | strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXX", MAXPATHLEN); | |
5260325f | 2843 | |
2844 | /* Create private directory for socket */ | |
8e7895b8 | 2845 | if (mkdtemp(auth_sock_dir) == NULL) { |
2846 | packet_send_debug("Agent forwarding disabled: " | |
2847 | "mkdtemp() failed: %.100s", strerror(errno)); | |
fa649821 | 2848 | restore_uid(); |
8e7895b8 | 2849 | xfree(auth_sock_name); |
2850 | xfree(auth_sock_dir); | |
2851 | auth_sock_name = NULL; | |
2852 | auth_sock_dir = NULL; | |
fa649821 | 2853 | return 0; |
2854 | } | |
8e7895b8 | 2855 | snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%d", |
2856 | auth_sock_dir, (int) getpid()); | |
5260325f | 2857 | |
e4f7282d | 2858 | /* delete agent socket on fatal() */ |
f0f32b8e | 2859 | fatal_add_cleanup(auth_sock_cleanup_proc, pw); |
e4f7282d | 2860 | |
5260325f | 2861 | /* Create the socket. */ |
2862 | sock = socket(AF_UNIX, SOCK_STREAM, 0); | |
2863 | if (sock < 0) | |
2864 | packet_disconnect("socket: %.100s", strerror(errno)); | |
2865 | ||
2866 | /* Bind it to the name. */ | |
2867 | memset(&sunaddr, 0, sizeof(sunaddr)); | |
2868 | sunaddr.sun_family = AF_UNIX; | |
8e7895b8 | 2869 | strncpy(sunaddr.sun_path, auth_sock_name, |
5260325f | 2870 | sizeof(sunaddr.sun_path)); |
2871 | ||
2872 | if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) | |
2873 | packet_disconnect("bind: %.100s", strerror(errno)); | |
2874 | ||
2875 | /* Restore the privileged uid. */ | |
2876 | restore_uid(); | |
2877 | ||
2878 | /* Start listening on the socket. */ | |
2879 | if (listen(sock, 5) < 0) | |
2880 | packet_disconnect("listen: %.100s", strerror(errno)); | |
2881 | ||
2882 | /* Allocate a channel for the authentication agent socket. */ | |
719fc62f | 2883 | nc = channel_new("auth socket", |
fa08c86b | 2884 | SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1, |
2885 | CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, | |
2886 | 0, xstrdup("auth socket"), 1); | |
719fc62f | 2887 | if (nc == NULL) { |
2888 | error("auth_input_request_forwarding: channel_new failed"); | |
f0f32b8e | 2889 | auth_sock_cleanup_proc(pw); |
750c256a | 2890 | fatal_remove_cleanup(auth_sock_cleanup_proc, pw); |
719fc62f | 2891 | close(sock); |
2892 | return 0; | |
2893 | } | |
8e7895b8 | 2894 | strlcpy(nc->path, auth_sock_name, sizeof(nc->path)); |
fa649821 | 2895 | return 1; |
8efc0c15 | 2896 | } |
2897 | ||
2898 | /* This is called to process an SSH_SMSG_AGENT_OPEN message. */ | |
2899 | ||
6ae2364d | 2900 | void |
188adeb2 | 2901 | auth_input_open_request(int type, int plen, void *ctxt) |
8efc0c15 | 2902 | { |
719fc62f | 2903 | Channel *c = NULL; |
2904 | int remote_id, sock; | |
8e7895b8 | 2905 | char *name; |
5260325f | 2906 | |
7368a6c8 | 2907 | packet_integrity_check(plen, 4, type); |
2908 | ||
5260325f | 2909 | /* Read the remote channel number from the message. */ |
719fc62f | 2910 | remote_id = packet_get_int(); |
5260325f | 2911 | |
aa3378df | 2912 | /* |
2913 | * Get a connection to the local authentication agent (this may again | |
2914 | * get forwarded). | |
2915 | */ | |
5260325f | 2916 | sock = ssh_get_authentication_socket(); |
2917 | ||
aa3378df | 2918 | /* |
2919 | * If we could not connect the agent, send an error message back to | |
2920 | * the server. This should never happen unless the agent dies, | |
2921 | * because authentication forwarding is only enabled if we have an | |
2922 | * agent. | |
2923 | */ | |
719fc62f | 2924 | if (sock >= 0) { |
8e7895b8 | 2925 | name = xstrdup("authentication agent connection"); |
2926 | c = channel_new("", SSH_CHANNEL_OPEN, sock, sock, | |
2927 | -1, 0, 0, 0, name, 1); | |
719fc62f | 2928 | if (c == NULL) { |
2929 | error("auth_input_open_request: channel_new failed"); | |
8e7895b8 | 2930 | xfree(name); |
719fc62f | 2931 | close(sock); |
2932 | } else { | |
2933 | c->remote_id = remote_id; | |
2934 | } | |
2935 | } | |
2936 | if (c == NULL) { | |
5260325f | 2937 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); |
719fc62f | 2938 | packet_put_int(remote_id); |
2939 | } else { | |
2940 | /* Send a confirmation to the remote host. */ | |
2941 | debug("Forwarding authentication connection."); | |
2942 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
2943 | packet_put_int(remote_id); | |
2944 | packet_put_int(c->self); | |
5260325f | 2945 | } |
5260325f | 2946 | packet_send(); |
8efc0c15 | 2947 | } |