]>
Commit | Line | Data |
---|---|---|
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 | * | |
15 | * | |
7e7327a1 | 16 | * SSH2 support added by Markus Friedl. |
bcbf86ec | 17 | * Copyright (c) 1999,2000 Markus Friedl. All rights reserved. |
18 | * Copyright (c) 1999 Dug Song. All rights reserved. | |
19 | * Copyright (c) 1999 Theo de Raadt. All rights reserved. | |
20 | * | |
21 | * Redistribution and use in source and binary forms, with or without | |
22 | * modification, are permitted provided that the following conditions | |
23 | * are met: | |
24 | * 1. Redistributions of source code must retain the above copyright | |
25 | * notice, this list of conditions and the following disclaimer. | |
26 | * 2. Redistributions in binary form must reproduce the above copyright | |
27 | * notice, this list of conditions and the following disclaimer in the | |
28 | * documentation and/or other materials provided with the distribution. | |
29 | * | |
30 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR | |
31 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES | |
32 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. | |
33 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, | |
34 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | |
35 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | |
36 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | |
37 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
38 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | |
39 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
5260325f | 40 | */ |
8efc0c15 | 41 | |
42 | #include "includes.h" | |
396c147e | 43 | RCSID("$OpenBSD: channels.c,v 1.127 2001/06/23 15:12:17 itojun Exp $"); |
8efc0c15 | 44 | |
45 | #include "ssh.h" | |
42f11eb2 | 46 | #include "ssh1.h" |
47 | #include "ssh2.h" | |
8efc0c15 | 48 | #include "packet.h" |
49 | #include "xmalloc.h" | |
8efc0c15 | 50 | #include "uidswap.h" |
42f11eb2 | 51 | #include "log.h" |
52 | #include "misc.h" | |
8efc0c15 | 53 | #include "channels.h" |
8efc0c15 | 54 | #include "compat.h" |
42f11eb2 | 55 | #include "canohost.h" |
4c8722d9 | 56 | #include "key.h" |
57 | #include "authfd.h" | |
7e7327a1 | 58 | |
8efc0c15 | 59 | |
8e7895b8 | 60 | /* -- channel core */ |
8efc0c15 | 61 | |
aa3378df | 62 | /* |
63 | * Pointer to an array containing all allocated channels. The array is | |
64 | * dynamically extended as needed. | |
65 | */ | |
719fc62f | 66 | static Channel **channels = NULL; |
8efc0c15 | 67 | |
aa3378df | 68 | /* |
69 | * Size of the channel array. All slots of the array must always be | |
719fc62f | 70 | * initialized (at least the type field); unused slots set to NULL |
aa3378df | 71 | */ |
8efc0c15 | 72 | static int channels_alloc = 0; |
73 | ||
aa3378df | 74 | /* |
75 | * Maximum file descriptor value used in any of the channels. This is | |
719fc62f | 76 | * updated in channel_new. |
aa3378df | 77 | */ |
39929cdb | 78 | static int channel_max_fd = 0; |
8efc0c15 | 79 | |
8efc0c15 | 80 | |
8e7895b8 | 81 | /* -- tcp forwarding */ |
8efc0c15 | 82 | |
aa3378df | 83 | /* |
84 | * Data structure for storing which hosts are permitted for forward requests. | |
85 | * The local sides of any remote forwards are stored in this array to prevent | |
86 | * a corrupt remote server from accessing arbitrary TCP/IP ports on our local | |
87 | * network (which might be behind a firewall). | |
88 | */ | |
5260325f | 89 | typedef struct { |
7368a6c8 | 90 | char *host_to_connect; /* Connect to 'host'. */ |
91 | u_short port_to_connect; /* Connect to 'port'. */ | |
92 | u_short listen_port; /* Remote side should listen port number. */ | |
8efc0c15 | 93 | } ForwardPermission; |
94 | ||
95 | /* List of all permitted host/port pairs to connect. */ | |
96 | static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION]; | |
8e7895b8 | 97 | |
8efc0c15 | 98 | /* Number of permitted host/port pairs in the array. */ |
99 | static int num_permitted_opens = 0; | |
aa3378df | 100 | /* |
101 | * If this is true, all opens are permitted. This is the case on the server | |
102 | * on which we have to trust the client anyway, and the user could do | |
103 | * anything after logging in anyway. | |
104 | */ | |
8efc0c15 | 105 | static int all_opens_permitted = 0; |
106 | ||
8efc0c15 | 107 | |
8e7895b8 | 108 | /* -- X11 forwarding */ |
42f11eb2 | 109 | |
8e7895b8 | 110 | /* Maximum number of fake X11 displays to try. */ |
111 | #define MAX_DISPLAYS 1000 | |
0490e609 | 112 | |
8e7895b8 | 113 | /* Saved X11 authentication protocol name. */ |
114 | static char *x11_saved_proto = NULL; | |
8efc0c15 | 115 | |
8e7895b8 | 116 | /* Saved X11 authentication data. This is the real data. */ |
117 | static char *x11_saved_data = NULL; | |
118 | static u_int x11_saved_data_len = 0; | |
119 | ||
120 | /* | |
121 | * Fake X11 authentication data. This is what the server will be sending us; | |
122 | * we should replace any occurrences of this by the real data. | |
123 | */ | |
124 | static char *x11_fake_data = NULL; | |
125 | static u_int x11_fake_data_len; | |
126 | ||
127 | ||
128 | /* -- agent forwarding */ | |
8efc0c15 | 129 | |
8e7895b8 | 130 | #define NUM_SOCKS 10 |
131 | ||
132 | /* Name and directory of socket for authentication agent forwarding. */ | |
133 | static char *auth_sock_name = NULL; | |
134 | static char *auth_sock_dir = NULL; | |
135 | ||
8e7895b8 | 136 | /* AF_UNSPEC or AF_INET or AF_INET6 */ |
137 | extern int IPv4or6; | |
138 | ||
139 | /* helper */ | |
396c147e | 140 | static void port_open_helper(Channel *c, char *rtype); |
8e7895b8 | 141 | |
142 | /* -- channel core */ | |
7368a6c8 | 143 | |
144 | Channel * | |
145 | channel_lookup(int id) | |
146 | { | |
147 | Channel *c; | |
719fc62f | 148 | |
3e98362e | 149 | if (id < 0 || id > channels_alloc) { |
7368a6c8 | 150 | log("channel_lookup: %d: bad id", id); |
151 | return NULL; | |
152 | } | |
719fc62f | 153 | c = channels[id]; |
154 | if (c == NULL) { | |
7368a6c8 | 155 | log("channel_lookup: %d: bad id: channel free", id); |
156 | return NULL; | |
157 | } | |
158 | return c; | |
159 | } | |
160 | ||
aa3378df | 161 | /* |
1d1ffb87 | 162 | * Register filedescriptors for a channel, used when allocating a channel or |
0fbe8c74 | 163 | * when the channel consumer/producer is ready, e.g. shell exec'd |
aa3378df | 164 | */ |
8efc0c15 | 165 | |
396c147e | 166 | static void |
a22aff1f | 167 | channel_register_fds(Channel *c, int rfd, int wfd, int efd, |
168 | int extusage, int nonblock) | |
8efc0c15 | 169 | { |
5260325f | 170 | /* Update the maximum file descriptor value. */ |
39929cdb | 171 | channel_max_fd = MAX(channel_max_fd, rfd); |
172 | channel_max_fd = MAX(channel_max_fd, wfd); | |
173 | channel_max_fd = MAX(channel_max_fd, efd); | |
174 | ||
aa3378df | 175 | /* XXX set close-on-exec -markus */ |
1d1ffb87 | 176 | |
0fbe8c74 | 177 | c->rfd = rfd; |
178 | c->wfd = wfd; | |
179 | c->sock = (rfd == wfd) ? rfd : -1; | |
180 | c->efd = efd; | |
181 | c->extended_usage = extusage; | |
a22aff1f | 182 | |
0ae4fe1d | 183 | /* XXX ugly hack: nonblock is only set by the server */ |
184 | if (nonblock && isatty(c->rfd)) { | |
94dfb550 | 185 | debug("channel %d: rfd %d isatty", c->self, c->rfd); |
0ae4fe1d | 186 | c->isatty = 1; |
187 | if (!isatty(c->wfd)) { | |
94dfb550 | 188 | error("channel %d: wfd %d is not a tty?", |
0ae4fe1d | 189 | c->self, c->wfd); |
190 | } | |
191 | } else { | |
192 | c->isatty = 0; | |
193 | } | |
194 | ||
a22aff1f | 195 | /* enable nonblocking mode */ |
196 | if (nonblock) { | |
197 | if (rfd != -1) | |
198 | set_nonblock(rfd); | |
199 | if (wfd != -1) | |
200 | set_nonblock(wfd); | |
201 | if (efd != -1) | |
202 | set_nonblock(efd); | |
203 | } | |
0fbe8c74 | 204 | } |
205 | ||
206 | /* | |
207 | * Allocate a new channel object and set its type and socket. This will cause | |
208 | * remote_name to be freed. | |
209 | */ | |
210 | ||
719fc62f | 211 | Channel * |
0fbe8c74 | 212 | channel_new(char *ctype, int type, int rfd, int wfd, int efd, |
a22aff1f | 213 | int window, int maxpack, int extusage, char *remote_name, int nonblock) |
0fbe8c74 | 214 | { |
215 | int i, found; | |
216 | Channel *c; | |
5260325f | 217 | |
218 | /* Do initial allocation if this is the first call. */ | |
219 | if (channels_alloc == 0) { | |
7e7327a1 | 220 | chan_init(); |
5260325f | 221 | channels_alloc = 10; |
719fc62f | 222 | channels = xmalloc(channels_alloc * sizeof(Channel *)); |
5260325f | 223 | for (i = 0; i < channels_alloc; i++) |
719fc62f | 224 | channels[i] = NULL; |
d6746a0b | 225 | fatal_add_cleanup((void (*) (void *)) channel_free_all, NULL); |
5260325f | 226 | } |
227 | /* Try to find a free slot where to put the new channel. */ | |
228 | for (found = -1, i = 0; i < channels_alloc; i++) | |
719fc62f | 229 | if (channels[i] == NULL) { |
5260325f | 230 | /* Found a free slot. */ |
231 | found = i; | |
232 | break; | |
233 | } | |
234 | if (found == -1) { | |
aa3378df | 235 | /* There are no free slots. Take last+1 slot and expand the array. */ |
5260325f | 236 | found = channels_alloc; |
237 | channels_alloc += 10; | |
de273eef | 238 | debug2("channel: expanding %d", channels_alloc); |
719fc62f | 239 | channels = xrealloc(channels, channels_alloc * sizeof(Channel *)); |
5260325f | 240 | for (i = found; i < channels_alloc; i++) |
719fc62f | 241 | channels[i] = NULL; |
5260325f | 242 | } |
719fc62f | 243 | /* Initialize and return new channel. */ |
244 | c = channels[found] = xmalloc(sizeof(Channel)); | |
5260325f | 245 | buffer_init(&c->input); |
246 | buffer_init(&c->output); | |
7368a6c8 | 247 | buffer_init(&c->extended); |
5260325f | 248 | chan_init_iostates(c); |
a22aff1f | 249 | channel_register_fds(c, rfd, wfd, efd, extusage, nonblock); |
5260325f | 250 | c->self = found; |
251 | c->type = type; | |
7368a6c8 | 252 | c->ctype = ctype; |
0b242b12 | 253 | c->local_window = window; |
254 | c->local_window_max = window; | |
255 | c->local_consumed = 0; | |
256 | c->local_maxpacket = maxpack; | |
5260325f | 257 | c->remote_id = -1; |
258 | c->remote_name = remote_name; | |
7368a6c8 | 259 | c->remote_window = 0; |
260 | c->remote_maxpacket = 0; | |
261 | c->cb_fn = NULL; | |
262 | c->cb_arg = NULL; | |
263 | c->cb_event = 0; | |
264 | c->dettach_user = NULL; | |
2e73a022 | 265 | c->input_filter = NULL; |
5260325f | 266 | debug("channel %d: new [%s]", found, remote_name); |
719fc62f | 267 | return c; |
7368a6c8 | 268 | } |
8efc0c15 | 269 | |
0fbe8c74 | 270 | /* Close all channel fd/socket. */ |
271 | ||
396c147e | 272 | static void |
0fbe8c74 | 273 | channel_close_fds(Channel *c) |
274 | { | |
6fd8622b | 275 | debug3("channel_close_fds: channel %d: r %d w %d e %d", |
276 | c->self, c->rfd, c->wfd, c->efd); | |
277 | ||
0fbe8c74 | 278 | if (c->sock != -1) { |
279 | close(c->sock); | |
280 | c->sock = -1; | |
281 | } | |
282 | if (c->rfd != -1) { | |
283 | close(c->rfd); | |
284 | c->rfd = -1; | |
285 | } | |
286 | if (c->wfd != -1) { | |
287 | close(c->wfd); | |
288 | c->wfd = -1; | |
289 | } | |
290 | if (c->efd != -1) { | |
291 | close(c->efd); | |
292 | c->efd = -1; | |
293 | } | |
294 | } | |
295 | ||
8e7895b8 | 296 | /* Free the channel and close its fd/socket. */ |
297 | ||
298 | void | |
299 | channel_free(Channel *c) | |
300 | { | |
301 | char *s; | |
302 | int i, n; | |
303 | ||
304 | for (n = 0, i = 0; i < channels_alloc; i++) | |
305 | if (channels[i]) | |
306 | n++; | |
307 | debug("channel_free: channel %d: %s, nchannels %d", c->self, | |
308 | c->remote_name ? c->remote_name : "???", n); | |
309 | ||
310 | s = channel_open_message(); | |
311 | debug3("channel_free: status: %s", s); | |
312 | xfree(s); | |
313 | ||
314 | if (c->dettach_user != NULL) { | |
315 | debug("channel_free: channel %d: dettaching channel user", c->self); | |
316 | c->dettach_user(c->self, NULL); | |
317 | } | |
318 | if (c->sock != -1) | |
319 | shutdown(c->sock, SHUT_RDWR); | |
320 | channel_close_fds(c); | |
321 | buffer_free(&c->input); | |
322 | buffer_free(&c->output); | |
323 | buffer_free(&c->extended); | |
324 | if (c->remote_name) { | |
325 | xfree(c->remote_name); | |
326 | c->remote_name = NULL; | |
327 | } | |
328 | channels[c->self] = NULL; | |
329 | xfree(c); | |
330 | } | |
331 | ||
8e7895b8 | 332 | void |
d6746a0b | 333 | channel_free_all(void) |
8e7895b8 | 334 | { |
335 | int i; | |
8e7895b8 | 336 | |
d6746a0b | 337 | for (i = 0; i < channels_alloc; i++) |
338 | if (channels[i] != NULL) | |
339 | channel_free(channels[i]); | |
8e7895b8 | 340 | } |
341 | ||
342 | /* | |
343 | * Closes the sockets/fds of all channels. This is used to close extra file | |
344 | * descriptors after a fork. | |
345 | */ | |
346 | ||
347 | void | |
348 | channel_close_all() | |
349 | { | |
350 | int i; | |
351 | ||
352 | for (i = 0; i < channels_alloc; i++) | |
353 | if (channels[i] != NULL) | |
354 | channel_close_fds(channels[i]); | |
355 | } | |
356 | ||
357 | /* | |
358 | * Returns true if no channel has too much buffered data, and false if one or | |
359 | * more channel is overfull. | |
360 | */ | |
361 | ||
362 | int | |
363 | channel_not_very_much_buffered_data() | |
364 | { | |
365 | u_int i; | |
366 | Channel *c; | |
367 | ||
368 | for (i = 0; i < channels_alloc; i++) { | |
369 | c = channels[i]; | |
370 | if (c != NULL && c->type == SSH_CHANNEL_OPEN) { | |
371 | if (!compat20 && buffer_len(&c->input) > packet_get_maxsize()) { | |
372 | debug("channel %d: big input buffer %d", | |
373 | c->self, buffer_len(&c->input)); | |
374 | return 0; | |
375 | } | |
376 | if (buffer_len(&c->output) > packet_get_maxsize()) { | |
377 | debug("channel %d: big output buffer %d", | |
378 | c->self, buffer_len(&c->output)); | |
379 | return 0; | |
380 | } | |
381 | } | |
382 | } | |
383 | return 1; | |
384 | } | |
385 | ||
386 | /* Returns true if any channel is still open. */ | |
387 | ||
388 | int | |
389 | channel_still_open() | |
390 | { | |
391 | int i; | |
392 | Channel *c; | |
393 | ||
394 | for (i = 0; i < channels_alloc; i++) { | |
395 | c = channels[i]; | |
396 | if (c == NULL) | |
397 | continue; | |
398 | switch (c->type) { | |
399 | case SSH_CHANNEL_X11_LISTENER: | |
400 | case SSH_CHANNEL_PORT_LISTENER: | |
401 | case SSH_CHANNEL_RPORT_LISTENER: | |
402 | case SSH_CHANNEL_CLOSED: | |
403 | case SSH_CHANNEL_AUTH_SOCKET: | |
404 | case SSH_CHANNEL_DYNAMIC: | |
405 | case SSH_CHANNEL_CONNECTING: | |
406 | case SSH_CHANNEL_ZOMBIE: | |
407 | continue; | |
408 | case SSH_CHANNEL_LARVAL: | |
409 | if (!compat20) | |
410 | fatal("cannot happen: SSH_CHANNEL_LARVAL"); | |
411 | continue; | |
412 | case SSH_CHANNEL_OPENING: | |
413 | case SSH_CHANNEL_OPEN: | |
414 | case SSH_CHANNEL_X11_OPEN: | |
415 | return 1; | |
416 | case SSH_CHANNEL_INPUT_DRAINING: | |
417 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
418 | if (!compat13) | |
419 | fatal("cannot happen: OUT_DRAIN"); | |
420 | return 1; | |
421 | default: | |
422 | fatal("channel_still_open: bad channel type %d", c->type); | |
423 | /* NOTREACHED */ | |
424 | } | |
425 | } | |
426 | return 0; | |
427 | } | |
428 | ||
429 | /* Returns the id of an open channel suitable for keepaliving */ | |
430 | ||
431 | int | |
432 | channel_find_open() | |
433 | { | |
434 | int i; | |
435 | Channel *c; | |
436 | ||
437 | for (i = 0; i < channels_alloc; i++) { | |
438 | c = channels[i]; | |
439 | if (c == NULL) | |
440 | continue; | |
441 | switch (c->type) { | |
442 | case SSH_CHANNEL_CLOSED: | |
443 | case SSH_CHANNEL_DYNAMIC: | |
444 | case SSH_CHANNEL_X11_LISTENER: | |
445 | case SSH_CHANNEL_PORT_LISTENER: | |
446 | case SSH_CHANNEL_RPORT_LISTENER: | |
447 | case SSH_CHANNEL_OPENING: | |
448 | case SSH_CHANNEL_CONNECTING: | |
449 | case SSH_CHANNEL_ZOMBIE: | |
450 | continue; | |
451 | case SSH_CHANNEL_LARVAL: | |
452 | case SSH_CHANNEL_AUTH_SOCKET: | |
453 | case SSH_CHANNEL_OPEN: | |
454 | case SSH_CHANNEL_X11_OPEN: | |
455 | return i; | |
456 | case SSH_CHANNEL_INPUT_DRAINING: | |
457 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
458 | if (!compat13) | |
459 | fatal("cannot happen: OUT_DRAIN"); | |
460 | return i; | |
461 | default: | |
462 | fatal("channel_find_open: bad channel type %d", c->type); | |
463 | /* NOTREACHED */ | |
464 | } | |
465 | } | |
466 | return -1; | |
467 | } | |
468 | ||
469 | ||
470 | /* | |
471 | * Returns a message describing the currently open forwarded connections, | |
472 | * suitable for sending to the client. The message contains crlf pairs for | |
473 | * newlines. | |
474 | */ | |
475 | ||
476 | char * | |
477 | channel_open_message() | |
478 | { | |
479 | Buffer buffer; | |
480 | Channel *c; | |
481 | char buf[1024], *cp; | |
482 | int i; | |
483 | ||
484 | buffer_init(&buffer); | |
485 | snprintf(buf, sizeof buf, "The following connections are open:\r\n"); | |
486 | buffer_append(&buffer, buf, strlen(buf)); | |
487 | for (i = 0; i < channels_alloc; i++) { | |
488 | c = channels[i]; | |
489 | if (c == NULL) | |
490 | continue; | |
491 | switch (c->type) { | |
492 | case SSH_CHANNEL_X11_LISTENER: | |
493 | case SSH_CHANNEL_PORT_LISTENER: | |
494 | case SSH_CHANNEL_RPORT_LISTENER: | |
495 | case SSH_CHANNEL_CLOSED: | |
496 | case SSH_CHANNEL_AUTH_SOCKET: | |
497 | case SSH_CHANNEL_ZOMBIE: | |
498 | continue; | |
499 | case SSH_CHANNEL_LARVAL: | |
500 | case SSH_CHANNEL_OPENING: | |
501 | case SSH_CHANNEL_CONNECTING: | |
502 | case SSH_CHANNEL_DYNAMIC: | |
503 | case SSH_CHANNEL_OPEN: | |
504 | case SSH_CHANNEL_X11_OPEN: | |
505 | case SSH_CHANNEL_INPUT_DRAINING: | |
506 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
507 | snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n", | |
508 | c->self, c->remote_name, | |
509 | c->type, c->remote_id, | |
510 | c->istate, buffer_len(&c->input), | |
511 | c->ostate, buffer_len(&c->output), | |
512 | c->rfd, c->wfd); | |
513 | buffer_append(&buffer, buf, strlen(buf)); | |
514 | continue; | |
515 | default: | |
516 | fatal("channel_open_message: bad channel type %d", c->type); | |
517 | /* NOTREACHED */ | |
518 | } | |
519 | } | |
520 | buffer_append(&buffer, "\0", 1); | |
521 | cp = xstrdup(buffer_ptr(&buffer)); | |
522 | buffer_free(&buffer); | |
523 | return cp; | |
524 | } | |
525 | ||
526 | void | |
527 | channel_send_open(int id) | |
528 | { | |
529 | Channel *c = channel_lookup(id); | |
530 | if (c == NULL) { | |
531 | log("channel_send_open: %d: bad id", id); | |
532 | return; | |
533 | } | |
534 | debug("send channel open %d", id); | |
535 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
536 | packet_put_cstring(c->ctype); | |
537 | packet_put_int(c->self); | |
538 | packet_put_int(c->local_window); | |
539 | packet_put_int(c->local_maxpacket); | |
540 | packet_send(); | |
541 | } | |
542 | ||
543 | void | |
544 | channel_request(int id, char *service, int wantconfirm) | |
545 | { | |
546 | channel_request_start(id, service, wantconfirm); | |
547 | packet_send(); | |
548 | debug("channel request %d: %s", id, service) ; | |
549 | } | |
550 | void | |
551 | channel_request_start(int id, char *service, int wantconfirm) | |
552 | { | |
553 | Channel *c = channel_lookup(id); | |
554 | if (c == NULL) { | |
555 | log("channel_request: %d: bad id", id); | |
556 | return; | |
557 | } | |
558 | packet_start(SSH2_MSG_CHANNEL_REQUEST); | |
559 | packet_put_int(c->remote_id); | |
560 | packet_put_cstring(service); | |
561 | packet_put_char(wantconfirm); | |
562 | } | |
563 | void | |
564 | channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg) | |
565 | { | |
566 | Channel *c = channel_lookup(id); | |
567 | if (c == NULL) { | |
568 | log("channel_register_callback: %d: bad id", id); | |
569 | return; | |
570 | } | |
571 | c->cb_event = mtype; | |
572 | c->cb_fn = fn; | |
573 | c->cb_arg = arg; | |
574 | } | |
575 | void | |
576 | channel_register_cleanup(int id, channel_callback_fn *fn) | |
577 | { | |
578 | Channel *c = channel_lookup(id); | |
579 | if (c == NULL) { | |
580 | log("channel_register_cleanup: %d: bad id", id); | |
581 | return; | |
582 | } | |
583 | c->dettach_user = fn; | |
584 | } | |
585 | void | |
586 | channel_cancel_cleanup(int id) | |
587 | { | |
588 | Channel *c = channel_lookup(id); | |
589 | if (c == NULL) { | |
590 | log("channel_cancel_cleanup: %d: bad id", id); | |
591 | return; | |
592 | } | |
593 | c->dettach_user = NULL; | |
594 | } | |
595 | void | |
596 | channel_register_filter(int id, channel_filter_fn *fn) | |
597 | { | |
598 | Channel *c = channel_lookup(id); | |
599 | if (c == NULL) { | |
600 | log("channel_register_filter: %d: bad id", id); | |
601 | return; | |
602 | } | |
603 | c->input_filter = fn; | |
604 | } | |
605 | ||
6ae2364d | 606 | void |
8e7895b8 | 607 | channel_set_fds(int id, int rfd, int wfd, int efd, |
608 | int extusage, int nonblock) | |
8efc0c15 | 609 | { |
8e7895b8 | 610 | Channel *c = channel_lookup(id); |
611 | if (c == NULL || c->type != SSH_CHANNEL_LARVAL) | |
612 | fatal("channel_activate for non-larval channel %d.", id); | |
613 | channel_register_fds(c, rfd, wfd, efd, extusage, nonblock); | |
614 | c->type = SSH_CHANNEL_OPEN; | |
615 | /* XXX window size? */ | |
616 | c->local_window = c->local_window_max = c->local_maxpacket * 2; | |
617 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); | |
618 | packet_put_int(c->remote_id); | |
619 | packet_put_int(c->local_window); | |
620 | packet_send(); | |
8efc0c15 | 621 | } |
622 | ||
aa3378df | 623 | /* |
7368a6c8 | 624 | * 'channel_pre*' are called just before select() to add any bits relevant to |
625 | * channels in the select bitmasks. | |
aa3378df | 626 | */ |
7368a6c8 | 627 | /* |
628 | * 'channel_post*': perform any appropriate operations for channels which | |
629 | * have events pending. | |
630 | */ | |
631 | typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset); | |
632 | chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE]; | |
633 | chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE]; | |
8efc0c15 | 634 | |
396c147e | 635 | static void |
7368a6c8 | 636 | channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset) |
8efc0c15 | 637 | { |
7368a6c8 | 638 | FD_SET(c->sock, readset); |
639 | } | |
5260325f | 640 | |
396c147e | 641 | static void |
97fb6912 | 642 | channel_pre_connecting(Channel *c, fd_set * readset, fd_set * writeset) |
643 | { | |
644 | debug3("channel %d: waiting for connection", c->self); | |
645 | FD_SET(c->sock, writeset); | |
646 | } | |
647 | ||
396c147e | 648 | static void |
7368a6c8 | 649 | channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset) |
650 | { | |
651 | if (buffer_len(&c->input) < packet_get_maxsize()) | |
652 | FD_SET(c->sock, readset); | |
653 | if (buffer_len(&c->output) > 0) | |
654 | FD_SET(c->sock, writeset); | |
655 | } | |
5260325f | 656 | |
396c147e | 657 | static void |
7368a6c8 | 658 | channel_pre_open_15(Channel *c, fd_set * readset, fd_set * writeset) |
659 | { | |
660 | /* test whether sockets are 'alive' for read/write */ | |
661 | if (c->istate == CHAN_INPUT_OPEN) | |
662 | if (buffer_len(&c->input) < packet_get_maxsize()) | |
663 | FD_SET(c->sock, readset); | |
664 | if (c->ostate == CHAN_OUTPUT_OPEN || | |
665 | c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
666 | if (buffer_len(&c->output) > 0) { | |
667 | FD_SET(c->sock, writeset); | |
668 | } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
669 | chan_obuf_empty(c); | |
670 | } | |
671 | } | |
672 | } | |
5260325f | 673 | |
396c147e | 674 | static void |
7e7327a1 | 675 | channel_pre_open_20(Channel *c, fd_set * readset, fd_set * writeset) |
676 | { | |
677 | if (c->istate == CHAN_INPUT_OPEN && | |
678 | c->remote_window > 0 && | |
679 | buffer_len(&c->input) < c->remote_window) | |
680 | FD_SET(c->rfd, readset); | |
681 | if (c->ostate == CHAN_OUTPUT_OPEN || | |
682 | c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
683 | if (buffer_len(&c->output) > 0) { | |
684 | FD_SET(c->wfd, writeset); | |
685 | } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
686 | chan_obuf_empty(c); | |
687 | } | |
688 | } | |
689 | /** XXX check close conditions, too */ | |
690 | if (c->efd != -1) { | |
691 | if (c->extended_usage == CHAN_EXTENDED_WRITE && | |
692 | buffer_len(&c->extended) > 0) | |
693 | FD_SET(c->efd, writeset); | |
694 | else if (c->extended_usage == CHAN_EXTENDED_READ && | |
695 | buffer_len(&c->extended) < c->remote_window) | |
696 | FD_SET(c->efd, readset); | |
697 | } | |
698 | } | |
699 | ||
396c147e | 700 | static void |
7368a6c8 | 701 | channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset) |
702 | { | |
703 | if (buffer_len(&c->input) == 0) { | |
704 | packet_start(SSH_MSG_CHANNEL_CLOSE); | |
705 | packet_put_int(c->remote_id); | |
706 | packet_send(); | |
707 | c->type = SSH_CHANNEL_CLOSED; | |
070adba2 | 708 | debug("channel %d: closing after input drain.", c->self); |
7368a6c8 | 709 | } |
710 | } | |
5260325f | 711 | |
396c147e | 712 | static void |
7368a6c8 | 713 | channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset) |
714 | { | |
715 | if (buffer_len(&c->output) == 0) | |
719fc62f | 716 | chan_mark_dead(c); |
6ae2364d | 717 | else |
7368a6c8 | 718 | FD_SET(c->sock, writeset); |
719 | } | |
5260325f | 720 | |
7368a6c8 | 721 | /* |
722 | * This is a special state for X11 authentication spoofing. An opened X11 | |
723 | * connection (when authentication spoofing is being done) remains in this | |
724 | * state until the first packet has been completely read. The authentication | |
725 | * data in that packet is then substituted by the real data if it matches the | |
726 | * fake data, and the channel is put into normal mode. | |
0b242b12 | 727 | * XXX All this happens at the client side. |
8e7895b8 | 728 | * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok |
7368a6c8 | 729 | */ |
396c147e | 730 | static int |
8e7895b8 | 731 | x11_open_helper(Buffer *b) |
7368a6c8 | 732 | { |
1e3b8b07 | 733 | u_char *ucp; |
734 | u_int proto_len, data_len; | |
5260325f | 735 | |
7368a6c8 | 736 | /* Check if the fixed size part of the packet is in buffer. */ |
8e7895b8 | 737 | if (buffer_len(b) < 12) |
7368a6c8 | 738 | return 0; |
739 | ||
740 | /* Parse the lengths of variable-length fields. */ | |
8e7895b8 | 741 | ucp = (u_char *) buffer_ptr(b); |
7368a6c8 | 742 | if (ucp[0] == 0x42) { /* Byte order MSB first. */ |
743 | proto_len = 256 * ucp[6] + ucp[7]; | |
744 | data_len = 256 * ucp[8] + ucp[9]; | |
745 | } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */ | |
746 | proto_len = ucp[6] + 256 * ucp[7]; | |
747 | data_len = ucp[8] + 256 * ucp[9]; | |
748 | } else { | |
749 | debug("Initial X11 packet contains bad byte order byte: 0x%x", | |
750 | ucp[0]); | |
751 | return -1; | |
752 | } | |
5260325f | 753 | |
7368a6c8 | 754 | /* Check if the whole packet is in buffer. */ |
8e7895b8 | 755 | if (buffer_len(b) < |
7368a6c8 | 756 | 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3)) |
757 | return 0; | |
5260325f | 758 | |
7368a6c8 | 759 | /* Check if authentication protocol matches. */ |
760 | if (proto_len != strlen(x11_saved_proto) || | |
761 | memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) { | |
762 | debug("X11 connection uses different authentication protocol."); | |
763 | return -1; | |
764 | } | |
765 | /* Check if authentication data matches our fake data. */ | |
766 | if (data_len != x11_fake_data_len || | |
767 | memcmp(ucp + 12 + ((proto_len + 3) & ~3), | |
768 | x11_fake_data, x11_fake_data_len) != 0) { | |
769 | debug("X11 auth data does not match fake data."); | |
770 | return -1; | |
771 | } | |
772 | /* Check fake data length */ | |
773 | if (x11_fake_data_len != x11_saved_data_len) { | |
774 | error("X11 fake_data_len %d != saved_data_len %d", | |
775 | x11_fake_data_len, x11_saved_data_len); | |
776 | return -1; | |
777 | } | |
778 | /* | |
779 | * Received authentication protocol and data match | |
780 | * our fake data. Substitute the fake data with real | |
781 | * data. | |
782 | */ | |
783 | memcpy(ucp + 12 + ((proto_len + 3) & ~3), | |
784 | x11_saved_data, x11_saved_data_len); | |
785 | return 1; | |
786 | } | |
5260325f | 787 | |
396c147e | 788 | static void |
7368a6c8 | 789 | channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset) |
790 | { | |
8e7895b8 | 791 | int ret = x11_open_helper(&c->output); |
7368a6c8 | 792 | if (ret == 1) { |
793 | /* Start normal processing for the channel. */ | |
794 | c->type = SSH_CHANNEL_OPEN; | |
a8be9f80 | 795 | channel_pre_open_13(c, readset, writeset); |
7368a6c8 | 796 | } else if (ret == -1) { |
797 | /* | |
798 | * We have received an X11 connection that has bad | |
799 | * authentication information. | |
800 | */ | |
54b974dc | 801 | log("X11 connection rejected because of wrong authentication."); |
7368a6c8 | 802 | buffer_clear(&c->input); |
803 | buffer_clear(&c->output); | |
804 | close(c->sock); | |
805 | c->sock = -1; | |
806 | c->type = SSH_CHANNEL_CLOSED; | |
807 | packet_start(SSH_MSG_CHANNEL_CLOSE); | |
808 | packet_put_int(c->remote_id); | |
809 | packet_send(); | |
810 | } | |
811 | } | |
5260325f | 812 | |
396c147e | 813 | static void |
0b242b12 | 814 | channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset) |
7368a6c8 | 815 | { |
8e7895b8 | 816 | int ret = x11_open_helper(&c->output); |
7368a6c8 | 817 | if (ret == 1) { |
818 | c->type = SSH_CHANNEL_OPEN; | |
d0c832f3 | 819 | if (compat20) |
820 | channel_pre_open_20(c, readset, writeset); | |
821 | else | |
822 | channel_pre_open_15(c, readset, writeset); | |
7368a6c8 | 823 | } else if (ret == -1) { |
824 | debug("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate); | |
0b242b12 | 825 | chan_read_failed(c); /** force close? */ |
7368a6c8 | 826 | chan_write_failed(c); |
827 | debug("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate); | |
828 | } | |
829 | } | |
5260325f | 830 | |
28b9cb4d | 831 | /* try to decode a socks4 header */ |
396c147e | 832 | static int |
28b9cb4d | 833 | channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset) |
0490e609 | 834 | { |
835 | u_char *p, *host; | |
53b8fe68 | 836 | int len, have, i, found; |
28b9cb4d | 837 | char username[256]; |
0490e609 | 838 | struct { |
839 | u_int8_t version; | |
840 | u_int8_t command; | |
841 | u_int16_t dest_port; | |
28b9cb4d | 842 | struct in_addr dest_addr; |
0490e609 | 843 | } s4_req, s4_rsp; |
844 | ||
28b9cb4d | 845 | debug2("channel %d: decode socks4", c->self); |
53b8fe68 | 846 | |
847 | have = buffer_len(&c->input); | |
848 | len = sizeof(s4_req); | |
849 | if (have < len) | |
850 | return 0; | |
851 | p = buffer_ptr(&c->input); | |
852 | for (found = 0, i = len; i < have; i++) { | |
853 | if (p[i] == '\0') { | |
854 | found = 1; | |
855 | break; | |
856 | } | |
857 | if (i > 1024) { | |
858 | /* the peer is probably sending garbage */ | |
859 | debug("channel %d: decode socks4: too long", | |
860 | c->self); | |
861 | return -1; | |
862 | } | |
863 | } | |
864 | if (!found) | |
865 | return 0; | |
0490e609 | 866 | buffer_get(&c->input, (char *)&s4_req.version, 1); |
867 | buffer_get(&c->input, (char *)&s4_req.command, 1); | |
868 | buffer_get(&c->input, (char *)&s4_req.dest_port, 2); | |
28b9cb4d | 869 | buffer_get(&c->input, (char *)&s4_req.dest_addr, 4); |
53b8fe68 | 870 | have = buffer_len(&c->input); |
0490e609 | 871 | p = buffer_ptr(&c->input); |
872 | len = strlen(p); | |
6683b40f | 873 | debug2("channel %d: decode socks4: user %s/%d", c->self, p, len); |
0490e609 | 874 | if (len > have) |
28b9cb4d | 875 | fatal("channel %d: decode socks4: len %d > have %d", |
0490e609 | 876 | c->self, len, have); |
877 | strlcpy(username, p, sizeof(username)); | |
878 | buffer_consume(&c->input, len); | |
879 | buffer_consume(&c->input, 1); /* trailing '\0' */ | |
880 | ||
28b9cb4d | 881 | host = inet_ntoa(s4_req.dest_addr); |
0490e609 | 882 | strlcpy(c->path, host, sizeof(c->path)); |
883 | c->host_port = ntohs(s4_req.dest_port); | |
884 | ||
6683b40f | 885 | debug("channel %d: dynamic request: socks4 host %s port %u command %u", |
886 | c->self, host, c->host_port, s4_req.command); | |
0490e609 | 887 | |
28b9cb4d | 888 | if (s4_req.command != 1) { |
889 | debug("channel %d: cannot handle: socks4 cn %d", | |
890 | c->self, s4_req.command); | |
891 | return -1; | |
0490e609 | 892 | } |
28b9cb4d | 893 | s4_rsp.version = 0; /* vn: 0 for reply */ |
894 | s4_rsp.command = 90; /* cd: req granted */ | |
0490e609 | 895 | s4_rsp.dest_port = 0; /* ignored */ |
28b9cb4d | 896 | s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */ |
0490e609 | 897 | buffer_append(&c->output, (char *)&s4_rsp, sizeof(s4_rsp)); |
28b9cb4d | 898 | return 1; |
0490e609 | 899 | } |
900 | ||
28b9cb4d | 901 | /* dynamic port forwarding */ |
396c147e | 902 | static void |
28b9cb4d | 903 | channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset) |
904 | { | |
905 | u_char *p; | |
906 | int have, ret; | |
907 | ||
908 | have = buffer_len(&c->input); | |
909 | ||
910 | debug2("channel %d: pre_dynamic: have %d", c->self, have); | |
070adba2 | 911 | /* buffer_dump(&c->input); */ |
28b9cb4d | 912 | /* check if the fixed size part of the packet is in buffer. */ |
913 | if (have < 4) { | |
914 | /* need more */ | |
915 | FD_SET(c->sock, readset); | |
916 | return; | |
917 | } | |
918 | /* try to guess the protocol */ | |
919 | p = buffer_ptr(&c->input); | |
920 | switch (p[0]) { | |
6683b40f | 921 | case 0x04: |
922 | ret = channel_decode_socks4(c, readset, writeset); | |
923 | break; | |
28b9cb4d | 924 | default: |
925 | ret = -1; | |
926 | break; | |
927 | } | |
928 | if (ret < 0) { | |
719fc62f | 929 | chan_mark_dead(c); |
28b9cb4d | 930 | } else if (ret == 0) { |
931 | debug2("channel %d: pre_dynamic: need more", c->self); | |
932 | /* need more */ | |
933 | FD_SET(c->sock, readset); | |
934 | } else { | |
935 | /* switch to the next state */ | |
936 | c->type = SSH_CHANNEL_OPENING; | |
937 | port_open_helper(c, "direct-tcpip"); | |
938 | } | |
939 | } | |
0490e609 | 940 | |
7368a6c8 | 941 | /* This is our fake X11 server socket. */ |
396c147e | 942 | static void |
7368a6c8 | 943 | channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset) |
944 | { | |
719fc62f | 945 | Channel *nc; |
7368a6c8 | 946 | struct sockaddr addr; |
719fc62f | 947 | int newsock; |
7368a6c8 | 948 | socklen_t addrlen; |
865ac82e | 949 | char buf[16384], *remote_ipaddr; |
0b242b12 | 950 | int remote_port; |
7368a6c8 | 951 | |
952 | if (FD_ISSET(c->sock, readset)) { | |
953 | debug("X11 connection requested."); | |
954 | addrlen = sizeof(addr); | |
955 | newsock = accept(c->sock, &addr, &addrlen); | |
956 | if (newsock < 0) { | |
957 | error("accept: %.100s", strerror(errno)); | |
958 | return; | |
5260325f | 959 | } |
865ac82e | 960 | remote_ipaddr = get_peer_ipaddr(newsock); |
0b242b12 | 961 | remote_port = get_peer_port(newsock); |
7368a6c8 | 962 | snprintf(buf, sizeof buf, "X11 connection from %.200s port %d", |
865ac82e | 963 | remote_ipaddr, remote_port); |
0b242b12 | 964 | |
719fc62f | 965 | nc = channel_new("accepted x11 socket", |
0b242b12 | 966 | SSH_CHANNEL_OPENING, newsock, newsock, -1, |
967 | c->local_window_max, c->local_maxpacket, | |
a22aff1f | 968 | 0, xstrdup(buf), 1); |
719fc62f | 969 | if (nc == NULL) { |
970 | close(newsock); | |
971 | xfree(remote_ipaddr); | |
972 | return; | |
973 | } | |
0b242b12 | 974 | if (compat20) { |
975 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
976 | packet_put_cstring("x11"); | |
719fc62f | 977 | packet_put_int(nc->self); |
0b242b12 | 978 | packet_put_int(c->local_window_max); |
979 | packet_put_int(c->local_maxpacket); | |
865ac82e | 980 | /* originator ipaddr and port */ |
981 | packet_put_cstring(remote_ipaddr); | |
d0c832f3 | 982 | if (datafellows & SSH_BUG_X11FWD) { |
983 | debug("ssh2 x11 bug compat mode"); | |
984 | } else { | |
985 | packet_put_int(remote_port); | |
986 | } | |
0b242b12 | 987 | packet_send(); |
988 | } else { | |
989 | packet_start(SSH_SMSG_X11_OPEN); | |
719fc62f | 990 | packet_put_int(nc->self); |
8e7895b8 | 991 | if (packet_get_protocol_flags() & |
992 | SSH_PROTOFLAG_HOST_IN_FWD_OPEN) | |
449c5ba5 | 993 | packet_put_cstring(buf); |
0b242b12 | 994 | packet_send(); |
995 | } | |
865ac82e | 996 | xfree(remote_ipaddr); |
8efc0c15 | 997 | } |
8efc0c15 | 998 | } |
999 | ||
396c147e | 1000 | static void |
0490e609 | 1001 | port_open_helper(Channel *c, char *rtype) |
1002 | { | |
1003 | int direct; | |
1004 | char buf[1024]; | |
1005 | char *remote_ipaddr = get_peer_ipaddr(c->sock); | |
1006 | u_short remote_port = get_peer_port(c->sock); | |
1007 | ||
1008 | direct = (strcmp(rtype, "direct-tcpip") == 0); | |
1009 | ||
1010 | snprintf(buf, sizeof buf, | |
1011 | "%s: listening port %d for %.100s port %d, " | |
1012 | "connect from %.200s port %d", | |
1013 | rtype, c->listening_port, c->path, c->host_port, | |
1014 | remote_ipaddr, remote_port); | |
1015 | ||
1016 | xfree(c->remote_name); | |
1017 | c->remote_name = xstrdup(buf); | |
1018 | ||
1019 | if (compat20) { | |
1020 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
1021 | packet_put_cstring(rtype); | |
1022 | packet_put_int(c->self); | |
1023 | packet_put_int(c->local_window_max); | |
1024 | packet_put_int(c->local_maxpacket); | |
1025 | if (direct) { | |
1026 | /* target host, port */ | |
1027 | packet_put_cstring(c->path); | |
1028 | packet_put_int(c->host_port); | |
1029 | } else { | |
1030 | /* listen address, port */ | |
1031 | packet_put_cstring(c->path); | |
1032 | packet_put_int(c->listening_port); | |
1033 | } | |
1034 | /* originator host and port */ | |
1035 | packet_put_cstring(remote_ipaddr); | |
1036 | packet_put_int(remote_port); | |
1037 | packet_send(); | |
1038 | } else { | |
1039 | packet_start(SSH_MSG_PORT_OPEN); | |
1040 | packet_put_int(c->self); | |
1041 | packet_put_cstring(c->path); | |
1042 | packet_put_int(c->host_port); | |
8e7895b8 | 1043 | if (packet_get_protocol_flags() & |
1044 | SSH_PROTOFLAG_HOST_IN_FWD_OPEN) | |
0490e609 | 1045 | packet_put_cstring(c->remote_name); |
1046 | packet_send(); | |
1047 | } | |
1048 | xfree(remote_ipaddr); | |
1049 | } | |
1050 | ||
aa3378df | 1051 | /* |
7368a6c8 | 1052 | * This socket is listening for connections to a forwarded TCP/IP port. |
aa3378df | 1053 | */ |
396c147e | 1054 | static void |
7368a6c8 | 1055 | channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset) |
1056 | { | |
0490e609 | 1057 | Channel *nc; |
7368a6c8 | 1058 | struct sockaddr addr; |
719fc62f | 1059 | int newsock, nextstate; |
7368a6c8 | 1060 | socklen_t addrlen; |
0490e609 | 1061 | char *rtype; |
fa08c86b | 1062 | |
7368a6c8 | 1063 | if (FD_ISSET(c->sock, readset)) { |
1064 | debug("Connection to port %d forwarding " | |
1065 | "to %.100s port %d requested.", | |
1066 | c->listening_port, c->path, c->host_port); | |
0490e609 | 1067 | |
1068 | rtype = (c->type == SSH_CHANNEL_RPORT_LISTENER) ? | |
1069 | "forwarded-tcpip" : "direct-tcpip"; | |
97430469 | 1070 | nextstate = (c->host_port == 0 && |
1071 | c->type != SSH_CHANNEL_RPORT_LISTENER) ? | |
1072 | SSH_CHANNEL_DYNAMIC : SSH_CHANNEL_OPENING; | |
0490e609 | 1073 | |
7368a6c8 | 1074 | addrlen = sizeof(addr); |
1075 | newsock = accept(c->sock, &addr, &addrlen); | |
1076 | if (newsock < 0) { | |
1077 | error("accept: %.100s", strerror(errno)); | |
1078 | return; | |
1079 | } | |
719fc62f | 1080 | nc = channel_new(rtype, |
0490e609 | 1081 | nextstate, newsock, newsock, -1, |
7368a6c8 | 1082 | c->local_window_max, c->local_maxpacket, |
0490e609 | 1083 | 0, xstrdup(rtype), 1); |
0490e609 | 1084 | if (nc == NULL) { |
719fc62f | 1085 | error("channel_post_port_listener: no new channel:"); |
1086 | close(newsock); | |
0490e609 | 1087 | return; |
7368a6c8 | 1088 | } |
0490e609 | 1089 | nc->listening_port = c->listening_port; |
1090 | nc->host_port = c->host_port; | |
1091 | strlcpy(nc->path, c->path, sizeof(nc->path)); | |
1092 | ||
1093 | if (nextstate != SSH_CHANNEL_DYNAMIC) | |
1094 | port_open_helper(nc, rtype); | |
7368a6c8 | 1095 | } |
1096 | } | |
8efc0c15 | 1097 | |
7368a6c8 | 1098 | /* |
1099 | * This is the authentication agent socket listening for connections from | |
1100 | * clients. | |
1101 | */ | |
396c147e | 1102 | static void |
7368a6c8 | 1103 | channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset) |
8efc0c15 | 1104 | { |
719fc62f | 1105 | Channel *nc; |
8e7895b8 | 1106 | char *name; |
719fc62f | 1107 | int newsock; |
5260325f | 1108 | struct sockaddr addr; |
48e671d5 | 1109 | socklen_t addrlen; |
5260325f | 1110 | |
7368a6c8 | 1111 | if (FD_ISSET(c->sock, readset)) { |
1112 | addrlen = sizeof(addr); | |
1113 | newsock = accept(c->sock, &addr, &addrlen); | |
1114 | if (newsock < 0) { | |
1115 | error("accept from auth socket: %.100s", strerror(errno)); | |
1116 | return; | |
1117 | } | |
8e7895b8 | 1118 | name = xstrdup("accepted auth socket"); |
719fc62f | 1119 | nc = channel_new("accepted auth socket", |
fa08c86b | 1120 | SSH_CHANNEL_OPENING, newsock, newsock, -1, |
1121 | c->local_window_max, c->local_maxpacket, | |
8e7895b8 | 1122 | 0, name, 1); |
719fc62f | 1123 | if (nc == NULL) { |
1124 | error("channel_post_auth_listener: channel_new failed"); | |
8e7895b8 | 1125 | xfree(name); |
719fc62f | 1126 | close(newsock); |
1127 | } | |
fa08c86b | 1128 | if (compat20) { |
1129 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
1130 | packet_put_cstring("auth-agent@openssh.com"); | |
719fc62f | 1131 | packet_put_int(nc->self); |
fa08c86b | 1132 | packet_put_int(c->local_window_max); |
1133 | packet_put_int(c->local_maxpacket); | |
1134 | } else { | |
1135 | packet_start(SSH_SMSG_AGENT_OPEN); | |
719fc62f | 1136 | packet_put_int(nc->self); |
fa08c86b | 1137 | } |
7368a6c8 | 1138 | packet_send(); |
1139 | } | |
1140 | } | |
5260325f | 1141 | |
396c147e | 1142 | static void |
97fb6912 | 1143 | channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset) |
1144 | { | |
d18e0850 | 1145 | int err = 0; |
1146 | int sz = sizeof(err); | |
1147 | ||
97fb6912 | 1148 | if (FD_ISSET(c->sock, writeset)) { |
d18e0850 | 1149 | if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, (char *)&err, |
1150 | &sz) < 0) { | |
1151 | err = errno; | |
1152 | error("getsockopt SO_ERROR failed"); | |
1153 | } | |
1154 | if (err == 0) { | |
1155 | debug("channel %d: connected", c->self); | |
1156 | c->type = SSH_CHANNEL_OPEN; | |
1157 | if (compat20) { | |
1158 | packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1159 | packet_put_int(c->remote_id); | |
1160 | packet_put_int(c->self); | |
1161 | packet_put_int(c->local_window); | |
1162 | packet_put_int(c->local_maxpacket); | |
1163 | } else { | |
1164 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1165 | packet_put_int(c->remote_id); | |
1166 | packet_put_int(c->self); | |
1167 | } | |
97fb6912 | 1168 | } else { |
d18e0850 | 1169 | debug("channel %d: not connected: %s", |
1170 | c->self, strerror(err)); | |
1171 | if (compat20) { | |
1172 | packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE); | |
1173 | packet_put_int(c->remote_id); | |
1174 | packet_put_int(SSH2_OPEN_CONNECT_FAILED); | |
1175 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { | |
1176 | packet_put_cstring(strerror(err)); | |
1177 | packet_put_cstring(""); | |
1178 | } | |
97fb6912 | 1179 | } else { |
d18e0850 | 1180 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); |
1181 | packet_put_int(c->remote_id); | |
97fb6912 | 1182 | } |
d18e0850 | 1183 | chan_mark_dead(c); |
97fb6912 | 1184 | } |
d18e0850 | 1185 | packet_send(); |
97fb6912 | 1186 | } |
1187 | } | |
1188 | ||
396c147e | 1189 | static int |
7368a6c8 | 1190 | channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset) |
1191 | { | |
1192 | char buf[16*1024]; | |
1193 | int len; | |
1194 | ||
6fd8622b | 1195 | if (c->rfd != -1 && |
7368a6c8 | 1196 | FD_ISSET(c->rfd, readset)) { |
1197 | len = read(c->rfd, buf, sizeof(buf)); | |
0fbe8c74 | 1198 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1199 | return 1; | |
7368a6c8 | 1200 | if (len <= 0) { |
0b242b12 | 1201 | debug("channel %d: read<=0 rfd %d len %d", |
7368a6c8 | 1202 | c->self, c->rfd, len); |
28b9cb4d | 1203 | if (c->type != SSH_CHANNEL_OPEN) { |
1204 | debug("channel %d: not open", c->self); | |
719fc62f | 1205 | chan_mark_dead(c); |
0490e609 | 1206 | return -1; |
28b9cb4d | 1207 | } else if (compat13) { |
7368a6c8 | 1208 | buffer_consume(&c->output, buffer_len(&c->output)); |
1209 | c->type = SSH_CHANNEL_INPUT_DRAINING; | |
8e7895b8 | 1210 | debug("channel %d: input draining.", c->self); |
7368a6c8 | 1211 | } else { |
1212 | chan_read_failed(c); | |
5260325f | 1213 | } |
7368a6c8 | 1214 | return -1; |
1215 | } | |
2e73a022 | 1216 | if(c->input_filter != NULL) { |
1217 | if (c->input_filter(c, buf, len) == -1) { | |
070adba2 | 1218 | debug("channel %d: filter stops", c->self); |
2e73a022 | 1219 | chan_read_failed(c); |
1220 | } | |
1221 | } else { | |
1222 | buffer_append(&c->input, buf, len); | |
1223 | } | |
7368a6c8 | 1224 | } |
1225 | return 1; | |
1226 | } | |
396c147e | 1227 | static int |
7368a6c8 | 1228 | channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset) |
1229 | { | |
95ce5599 | 1230 | struct termios tio; |
7368a6c8 | 1231 | int len; |
1232 | ||
1233 | /* Send buffered output data to the socket. */ | |
6fd8622b | 1234 | if (c->wfd != -1 && |
7368a6c8 | 1235 | FD_ISSET(c->wfd, writeset) && |
1236 | buffer_len(&c->output) > 0) { | |
1237 | len = write(c->wfd, buffer_ptr(&c->output), | |
0fbe8c74 | 1238 | buffer_len(&c->output)); |
1239 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) | |
1240 | return 1; | |
7368a6c8 | 1241 | if (len <= 0) { |
28b9cb4d | 1242 | if (c->type != SSH_CHANNEL_OPEN) { |
1243 | debug("channel %d: not open", c->self); | |
719fc62f | 1244 | chan_mark_dead(c); |
28b9cb4d | 1245 | return -1; |
1246 | } else if (compat13) { | |
7368a6c8 | 1247 | buffer_consume(&c->output, buffer_len(&c->output)); |
8e7895b8 | 1248 | debug("channel %d: input draining.", c->self); |
7368a6c8 | 1249 | c->type = SSH_CHANNEL_INPUT_DRAINING; |
1250 | } else { | |
1251 | chan_write_failed(c); | |
5260325f | 1252 | } |
7368a6c8 | 1253 | return -1; |
1254 | } | |
0ae4fe1d | 1255 | if (compat20 && c->isatty) { |
0ae4fe1d | 1256 | if (tcgetattr(c->wfd, &tio) == 0 && |
1257 | !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) { | |
1258 | /* | |
1259 | * Simulate echo to reduce the impact of | |
355724fc | 1260 | * traffic analysis. We need to match the |
95ce5599 | 1261 | * size of a SSH2_MSG_CHANNEL_DATA message |
1262 | * (4 byte channel id + data) | |
0ae4fe1d | 1263 | */ |
95ce5599 | 1264 | packet_send_ignore(4 + len); |
0ae4fe1d | 1265 | packet_send(); |
0ae4fe1d | 1266 | } |
1267 | } | |
7368a6c8 | 1268 | buffer_consume(&c->output, len); |
7e7327a1 | 1269 | if (compat20 && len > 0) { |
1270 | c->local_consumed += len; | |
1271 | } | |
1272 | } | |
1273 | return 1; | |
1274 | } | |
396c147e | 1275 | static int |
7e7327a1 | 1276 | channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset) |
1277 | { | |
1278 | char buf[16*1024]; | |
1279 | int len; | |
1280 | ||
8ce64345 | 1281 | /** XXX handle drain efd, too */ |
7e7327a1 | 1282 | if (c->efd != -1) { |
1283 | if (c->extended_usage == CHAN_EXTENDED_WRITE && | |
1284 | FD_ISSET(c->efd, writeset) && | |
1285 | buffer_len(&c->extended) > 0) { | |
1286 | len = write(c->efd, buffer_ptr(&c->extended), | |
1287 | buffer_len(&c->extended)); | |
de273eef | 1288 | debug2("channel %d: written %d to efd %d", |
7e7327a1 | 1289 | c->self, len, c->efd); |
ee55dacf | 1290 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1291 | return 1; | |
1292 | if (len <= 0) { | |
1293 | debug2("channel %d: closing write-efd %d", | |
1294 | c->self, c->efd); | |
1295 | close(c->efd); | |
1296 | c->efd = -1; | |
1297 | } else { | |
7e7327a1 | 1298 | buffer_consume(&c->extended, len); |
1299 | c->local_consumed += len; | |
1300 | } | |
1301 | } else if (c->extended_usage == CHAN_EXTENDED_READ && | |
1302 | FD_ISSET(c->efd, readset)) { | |
1303 | len = read(c->efd, buf, sizeof(buf)); | |
de273eef | 1304 | debug2("channel %d: read %d from efd %d", |
7e7327a1 | 1305 | c->self, len, c->efd); |
ee55dacf | 1306 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1307 | return 1; | |
1308 | if (len <= 0) { | |
1309 | debug2("channel %d: closing read-efd %d", | |
8ce64345 | 1310 | c->self, c->efd); |
1311 | close(c->efd); | |
1312 | c->efd = -1; | |
ee55dacf | 1313 | } else { |
7e7327a1 | 1314 | buffer_append(&c->extended, buf, len); |
ee55dacf | 1315 | } |
7e7327a1 | 1316 | } |
1317 | } | |
1318 | return 1; | |
1319 | } | |
396c147e | 1320 | static int |
ee55dacf | 1321 | channel_check_window(Channel *c) |
7e7327a1 | 1322 | { |
28b9cb4d | 1323 | if (c->type == SSH_CHANNEL_OPEN && |
1324 | !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) && | |
7e7327a1 | 1325 | c->local_window < c->local_window_max/2 && |
1326 | c->local_consumed > 0) { | |
1327 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); | |
1328 | packet_put_int(c->remote_id); | |
1329 | packet_put_int(c->local_consumed); | |
1330 | packet_send(); | |
de273eef | 1331 | debug2("channel %d: window %d sent adjust %d", |
7e7327a1 | 1332 | c->self, c->local_window, |
1333 | c->local_consumed); | |
1334 | c->local_window += c->local_consumed; | |
1335 | c->local_consumed = 0; | |
7368a6c8 | 1336 | } |
1337 | return 1; | |
1338 | } | |
5260325f | 1339 | |
396c147e | 1340 | static void |
7368a6c8 | 1341 | channel_post_open_1(Channel *c, fd_set * readset, fd_set * writeset) |
1342 | { | |
1343 | channel_handle_rfd(c, readset, writeset); | |
1344 | channel_handle_wfd(c, readset, writeset); | |
1345 | } | |
aa3378df | 1346 | |
396c147e | 1347 | static void |
7e7327a1 | 1348 | channel_post_open_2(Channel *c, fd_set * readset, fd_set * writeset) |
1349 | { | |
1350 | channel_handle_rfd(c, readset, writeset); | |
1351 | channel_handle_wfd(c, readset, writeset); | |
1352 | channel_handle_efd(c, readset, writeset); | |
ee55dacf | 1353 | |
1354 | channel_check_window(c); | |
7e7327a1 | 1355 | } |
1356 | ||
396c147e | 1357 | static void |
7368a6c8 | 1358 | channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset) |
1359 | { | |
1360 | int len; | |
1361 | /* Send buffered output data to the socket. */ | |
1362 | if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) { | |
1363 | len = write(c->sock, buffer_ptr(&c->output), | |
1364 | buffer_len(&c->output)); | |
1365 | if (len <= 0) | |
1366 | buffer_consume(&c->output, buffer_len(&c->output)); | |
1367 | else | |
1368 | buffer_consume(&c->output, len); | |
1369 | } | |
1370 | } | |
5260325f | 1371 | |
396c147e | 1372 | static void |
7e7327a1 | 1373 | channel_handler_init_20(void) |
1374 | { | |
1375 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_20; | |
0b242b12 | 1376 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; |
7e7327a1 | 1377 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; |
fa08c86b | 1378 | channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener; |
0b242b12 | 1379 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; |
fa08c86b | 1380 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; |
97fb6912 | 1381 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1382 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7e7327a1 | 1383 | |
1384 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_2; | |
1385 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
fa08c86b | 1386 | channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener; |
0b242b12 | 1387 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; |
fa08c86b | 1388 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; |
97fb6912 | 1389 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
28b9cb4d | 1390 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_2; |
7e7327a1 | 1391 | } |
1392 | ||
396c147e | 1393 | static void |
7368a6c8 | 1394 | channel_handler_init_13(void) |
1395 | { | |
1396 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13; | |
1397 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13; | |
1398 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; | |
1399 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; | |
1400 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; | |
1401 | channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining; | |
1402 | channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining; | |
97fb6912 | 1403 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1404 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7368a6c8 | 1405 | |
1406 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1; | |
1407 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; | |
1408 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
1409 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; | |
1410 | channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13; | |
97fb6912 | 1411 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
28b9cb4d | 1412 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1; |
7368a6c8 | 1413 | } |
5260325f | 1414 | |
396c147e | 1415 | static void |
7368a6c8 | 1416 | channel_handler_init_15(void) |
1417 | { | |
1418 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_15; | |
0b242b12 | 1419 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; |
7368a6c8 | 1420 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; |
1421 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; | |
1422 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; | |
97fb6912 | 1423 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1424 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7368a6c8 | 1425 | |
1426 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; | |
1427 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
1428 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; | |
1429 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1; | |
97fb6912 | 1430 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
28b9cb4d | 1431 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1; |
7368a6c8 | 1432 | } |
1433 | ||
396c147e | 1434 | static void |
7368a6c8 | 1435 | channel_handler_init(void) |
1436 | { | |
1437 | int i; | |
1438 | for(i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) { | |
1439 | channel_pre[i] = NULL; | |
1440 | channel_post[i] = NULL; | |
1441 | } | |
7e7327a1 | 1442 | if (compat20) |
1443 | channel_handler_init_20(); | |
1444 | else if (compat13) | |
7368a6c8 | 1445 | channel_handler_init_13(); |
1446 | else | |
1447 | channel_handler_init_15(); | |
1448 | } | |
1449 | ||
396c147e | 1450 | static void |
7368a6c8 | 1451 | channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset) |
1452 | { | |
1453 | static int did_init = 0; | |
1454 | int i; | |
1455 | Channel *c; | |
1456 | ||
1457 | if (!did_init) { | |
1458 | channel_handler_init(); | |
1459 | did_init = 1; | |
1460 | } | |
1461 | for (i = 0; i < channels_alloc; i++) { | |
719fc62f | 1462 | c = channels[i]; |
1463 | if (c == NULL) | |
5260325f | 1464 | continue; |
6fd8622b | 1465 | if (ftab[c->type] != NULL) |
1466 | (*ftab[c->type])(c, readset, writeset); | |
ee55dacf | 1467 | if (chan_is_dead(c)) { |
1468 | /* | |
1469 | * we have to remove the fd's from the select mask | |
1470 | * before the channels are free'd and the fd's are | |
1471 | * closed | |
1472 | */ | |
1473 | if (c->wfd != -1) | |
1474 | FD_CLR(c->wfd, writeset); | |
1475 | if (c->rfd != -1) | |
1476 | FD_CLR(c->rfd, readset); | |
1477 | if (c->efd != -1) { | |
1478 | if (c->extended_usage == CHAN_EXTENDED_READ) | |
1479 | FD_CLR(c->efd, readset); | |
1480 | if (c->extended_usage == CHAN_EXTENDED_WRITE) | |
1481 | FD_CLR(c->efd, writeset); | |
1482 | } | |
719fc62f | 1483 | channel_free(c); |
ee55dacf | 1484 | } |
8efc0c15 | 1485 | } |
8efc0c15 | 1486 | } |
1487 | ||
8e7895b8 | 1488 | /* |
1489 | * Allocate/update select bitmasks and add any bits relevant to channels in | |
1490 | * select bitmasks. | |
1491 | */ | |
6ae2364d | 1492 | void |
c422989b | 1493 | channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp, |
1494 | int rekeying) | |
7368a6c8 | 1495 | { |
39929cdb | 1496 | int n; |
1497 | u_int sz; | |
1498 | ||
1499 | n = MAX(*maxfdp, channel_max_fd); | |
1500 | ||
1501 | sz = howmany(n+1, NFDBITS) * sizeof(fd_mask); | |
1502 | if (*readsetp == NULL || n > *maxfdp) { | |
1503 | if (*readsetp) | |
1504 | xfree(*readsetp); | |
1505 | if (*writesetp) | |
1506 | xfree(*writesetp); | |
1507 | *readsetp = xmalloc(sz); | |
1508 | *writesetp = xmalloc(sz); | |
1509 | *maxfdp = n; | |
1510 | } | |
1511 | memset(*readsetp, 0, sz); | |
1512 | memset(*writesetp, 0, sz); | |
1513 | ||
c422989b | 1514 | if (!rekeying) |
1515 | channel_handler(channel_pre, *readsetp, *writesetp); | |
7368a6c8 | 1516 | } |
1517 | ||
8e7895b8 | 1518 | /* |
1519 | * After select, perform any appropriate operations for channels which have | |
1520 | * events pending. | |
1521 | */ | |
6ae2364d | 1522 | void |
7368a6c8 | 1523 | channel_after_select(fd_set * readset, fd_set * writeset) |
1524 | { | |
1525 | channel_handler(channel_post, readset, writeset); | |
1526 | } | |
1527 | ||
8e7895b8 | 1528 | |
39929cdb | 1529 | /* If there is data to send to the connection, enqueue some of it now. */ |
8efc0c15 | 1530 | |
6ae2364d | 1531 | void |
5260325f | 1532 | channel_output_poll() |
8efc0c15 | 1533 | { |
5260325f | 1534 | int len, i; |
7368a6c8 | 1535 | Channel *c; |
5260325f | 1536 | |
1537 | for (i = 0; i < channels_alloc; i++) { | |
719fc62f | 1538 | c = channels[i]; |
1539 | if (c == NULL) | |
1540 | continue; | |
48e671d5 | 1541 | |
8e7895b8 | 1542 | /* |
1543 | * We are only interested in channels that can have buffered | |
1544 | * incoming data. | |
1545 | */ | |
48e671d5 | 1546 | if (compat13) { |
7368a6c8 | 1547 | if (c->type != SSH_CHANNEL_OPEN && |
1548 | c->type != SSH_CHANNEL_INPUT_DRAINING) | |
48e671d5 | 1549 | continue; |
1550 | } else { | |
7368a6c8 | 1551 | if (c->type != SSH_CHANNEL_OPEN) |
48e671d5 | 1552 | continue; |
48e671d5 | 1553 | } |
e78a59f5 | 1554 | if (compat20 && |
1555 | (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) { | |
ee55dacf | 1556 | /* XXX is this true? */ |
61f8a1d1 | 1557 | debug2("channel %d: no data after CLOSE", c->self); |
7e7327a1 | 1558 | continue; |
1559 | } | |
5260325f | 1560 | |
1561 | /* Get the amount of buffered data for this channel. */ | |
ee55dacf | 1562 | if ((c->istate == CHAN_INPUT_OPEN || |
1563 | c->istate == CHAN_INPUT_WAIT_DRAIN) && | |
1564 | (len = buffer_len(&c->input)) > 0) { | |
8e7895b8 | 1565 | /* |
1566 | * Send some data for the other side over the secure | |
1567 | * connection. | |
1568 | */ | |
7e7327a1 | 1569 | if (compat20) { |
1570 | if (len > c->remote_window) | |
1571 | len = c->remote_window; | |
1572 | if (len > c->remote_maxpacket) | |
1573 | len = c->remote_maxpacket; | |
5260325f | 1574 | } else { |
7e7327a1 | 1575 | if (packet_is_interactive()) { |
1576 | if (len > 1024) | |
1577 | len = 512; | |
1578 | } else { | |
1579 | /* Keep the packets at reasonable size. */ | |
1580 | if (len > packet_get_maxsize()/2) | |
1581 | len = packet_get_maxsize()/2; | |
1582 | } | |
5260325f | 1583 | } |
7368a6c8 | 1584 | if (len > 0) { |
7e7327a1 | 1585 | packet_start(compat20 ? |
1586 | SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA); | |
7368a6c8 | 1587 | packet_put_int(c->remote_id); |
1588 | packet_put_string(buffer_ptr(&c->input), len); | |
1589 | packet_send(); | |
1590 | buffer_consume(&c->input, len); | |
1591 | c->remote_window -= len; | |
7368a6c8 | 1592 | } |
1593 | } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) { | |
5260325f | 1594 | if (compat13) |
1595 | fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3"); | |
aa3378df | 1596 | /* |
1597 | * input-buffer is empty and read-socket shutdown: | |
1598 | * tell peer, that we will not send more data: send IEOF | |
1599 | */ | |
7368a6c8 | 1600 | chan_ibuf_empty(c); |
5260325f | 1601 | } |
7e7327a1 | 1602 | /* Send extended data, i.e. stderr */ |
1603 | if (compat20 && | |
1604 | c->remote_window > 0 && | |
1605 | (len = buffer_len(&c->extended)) > 0 && | |
1606 | c->extended_usage == CHAN_EXTENDED_READ) { | |
ee55dacf | 1607 | debug2("channel %d: rwin %d elen %d euse %d", |
1608 | c->self, c->remote_window, buffer_len(&c->extended), | |
1609 | c->extended_usage); | |
7e7327a1 | 1610 | if (len > c->remote_window) |
1611 | len = c->remote_window; | |
1612 | if (len > c->remote_maxpacket) | |
1613 | len = c->remote_maxpacket; | |
1614 | packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA); | |
1615 | packet_put_int(c->remote_id); | |
1616 | packet_put_int(SSH2_EXTENDED_DATA_STDERR); | |
1617 | packet_put_string(buffer_ptr(&c->extended), len); | |
1618 | packet_send(); | |
1619 | buffer_consume(&c->extended, len); | |
1620 | c->remote_window -= len; | |
ee55dacf | 1621 | debug2("channel %d: sent ext data %d", c->self, len); |
7e7327a1 | 1622 | } |
8efc0c15 | 1623 | } |
8efc0c15 | 1624 | } |
1625 | ||
8e7895b8 | 1626 | |
1627 | /* -- protocol input */ | |
8efc0c15 | 1628 | |
6ae2364d | 1629 | void |
188adeb2 | 1630 | channel_input_data(int type, int plen, void *ctxt) |
8efc0c15 | 1631 | { |
48e671d5 | 1632 | int id; |
5260325f | 1633 | char *data; |
1e3b8b07 | 1634 | u_int data_len; |
7368a6c8 | 1635 | Channel *c; |
5260325f | 1636 | |
1637 | /* Get the channel number and verify it. */ | |
48e671d5 | 1638 | id = packet_get_int(); |
7368a6c8 | 1639 | c = channel_lookup(id); |
1640 | if (c == NULL) | |
48e671d5 | 1641 | packet_disconnect("Received data for nonexistent channel %d.", id); |
5260325f | 1642 | |
1643 | /* Ignore any data for non-open channels (might happen on close) */ | |
7368a6c8 | 1644 | if (c->type != SSH_CHANNEL_OPEN && |
1645 | c->type != SSH_CHANNEL_X11_OPEN) | |
48e671d5 | 1646 | return; |
1647 | ||
1648 | /* same for protocol 1.5 if output end is no longer open */ | |
7368a6c8 | 1649 | if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) |
5260325f | 1650 | return; |
1651 | ||
1652 | /* Get the data. */ | |
1653 | data = packet_get_string(&data_len); | |
6ae2364d | 1654 | packet_done(); |
7368a6c8 | 1655 | |
7e7327a1 | 1656 | if (compat20){ |
1657 | if (data_len > c->local_maxpacket) { | |
1658 | log("channel %d: rcvd big packet %d, maxpack %d", | |
1659 | c->self, data_len, c->local_maxpacket); | |
1660 | } | |
1661 | if (data_len > c->local_window) { | |
1662 | log("channel %d: rcvd too much data %d, win %d", | |
1663 | c->self, data_len, c->local_window); | |
1664 | xfree(data); | |
1665 | return; | |
1666 | } | |
1667 | c->local_window -= data_len; | |
1668 | }else{ | |
1669 | packet_integrity_check(plen, 4 + 4 + data_len, type); | |
1670 | } | |
7368a6c8 | 1671 | buffer_append(&c->output, data, data_len); |
5260325f | 1672 | xfree(data); |
8efc0c15 | 1673 | } |
8e7895b8 | 1674 | |
6ae2364d | 1675 | void |
188adeb2 | 1676 | channel_input_extended_data(int type, int plen, void *ctxt) |
7e7327a1 | 1677 | { |
1678 | int id; | |
1679 | int tcode; | |
1680 | char *data; | |
1e3b8b07 | 1681 | u_int data_len; |
7e7327a1 | 1682 | Channel *c; |
1683 | ||
1684 | /* Get the channel number and verify it. */ | |
1685 | id = packet_get_int(); | |
1686 | c = channel_lookup(id); | |
1687 | ||
1688 | if (c == NULL) | |
1689 | packet_disconnect("Received extended_data for bad channel %d.", id); | |
1690 | if (c->type != SSH_CHANNEL_OPEN) { | |
1691 | log("channel %d: ext data for non open", id); | |
1692 | return; | |
1693 | } | |
1694 | tcode = packet_get_int(); | |
1695 | if (c->efd == -1 || | |
1696 | c->extended_usage != CHAN_EXTENDED_WRITE || | |
1697 | tcode != SSH2_EXTENDED_DATA_STDERR) { | |
1698 | log("channel %d: bad ext data", c->self); | |
1699 | return; | |
1700 | } | |
1701 | data = packet_get_string(&data_len); | |
6ae2364d | 1702 | packet_done(); |
7e7327a1 | 1703 | if (data_len > c->local_window) { |
1704 | log("channel %d: rcvd too much extended_data %d, win %d", | |
1705 | c->self, data_len, c->local_window); | |
1706 | xfree(data); | |
1707 | return; | |
1708 | } | |
de273eef | 1709 | debug2("channel %d: rcvd ext data %d", c->self, data_len); |
7e7327a1 | 1710 | c->local_window -= data_len; |
1711 | buffer_append(&c->extended, data, data_len); | |
1712 | xfree(data); | |
1713 | } | |
1714 | ||
6ae2364d | 1715 | void |
188adeb2 | 1716 | channel_input_ieof(int type, int plen, void *ctxt) |
7368a6c8 | 1717 | { |
1718 | int id; | |
1719 | Channel *c; | |
1720 | ||
1721 | packet_integrity_check(plen, 4, type); | |
1722 | ||
1723 | id = packet_get_int(); | |
1724 | c = channel_lookup(id); | |
1725 | if (c == NULL) | |
1726 | packet_disconnect("Received ieof for nonexistent channel %d.", id); | |
1727 | chan_rcvd_ieof(c); | |
1728 | } | |
8efc0c15 | 1729 | |
6ae2364d | 1730 | void |
188adeb2 | 1731 | channel_input_close(int type, int plen, void *ctxt) |
8efc0c15 | 1732 | { |
7368a6c8 | 1733 | int id; |
1734 | Channel *c; | |
5260325f | 1735 | |
7368a6c8 | 1736 | packet_integrity_check(plen, 4, type); |
1737 | ||
1738 | id = packet_get_int(); | |
1739 | c = channel_lookup(id); | |
1740 | if (c == NULL) | |
1741 | packet_disconnect("Received close for nonexistent channel %d.", id); | |
aa3378df | 1742 | |
1743 | /* | |
1744 | * Send a confirmation that we have closed the channel and no more | |
1745 | * data is coming for it. | |
1746 | */ | |
5260325f | 1747 | packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION); |
7368a6c8 | 1748 | packet_put_int(c->remote_id); |
5260325f | 1749 | packet_send(); |
1750 | ||
aa3378df | 1751 | /* |
1752 | * If the channel is in closed state, we have sent a close request, | |
1753 | * and the other side will eventually respond with a confirmation. | |
1754 | * Thus, we cannot free the channel here, because then there would be | |
1755 | * no-one to receive the confirmation. The channel gets freed when | |
1756 | * the confirmation arrives. | |
1757 | */ | |
7368a6c8 | 1758 | if (c->type != SSH_CHANNEL_CLOSED) { |
aa3378df | 1759 | /* |
1760 | * Not a closed channel - mark it as draining, which will | |
1761 | * cause it to be freed later. | |
1762 | */ | |
7368a6c8 | 1763 | buffer_consume(&c->input, buffer_len(&c->input)); |
1764 | c->type = SSH_CHANNEL_OUTPUT_DRAINING; | |
5260325f | 1765 | } |
8efc0c15 | 1766 | } |
1767 | ||
7368a6c8 | 1768 | /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */ |
6ae2364d | 1769 | void |
188adeb2 | 1770 | channel_input_oclose(int type, int plen, void *ctxt) |
8efc0c15 | 1771 | { |
7368a6c8 | 1772 | int id = packet_get_int(); |
1773 | Channel *c = channel_lookup(id); | |
1774 | packet_integrity_check(plen, 4, type); | |
1775 | if (c == NULL) | |
1776 | packet_disconnect("Received oclose for nonexistent channel %d.", id); | |
1777 | chan_rcvd_oclose(c); | |
8efc0c15 | 1778 | } |
1779 | ||
6ae2364d | 1780 | void |
188adeb2 | 1781 | channel_input_close_confirmation(int type, int plen, void *ctxt) |
7368a6c8 | 1782 | { |
1783 | int id = packet_get_int(); | |
1784 | Channel *c = channel_lookup(id); | |
1785 | ||
6ae2364d | 1786 | packet_done(); |
7368a6c8 | 1787 | if (c == NULL) |
1788 | packet_disconnect("Received close confirmation for " | |
1789 | "out-of-range channel %d.", id); | |
1790 | if (c->type != SSH_CHANNEL_CLOSED) | |
1791 | packet_disconnect("Received close confirmation for " | |
1792 | "non-closed channel %d (type %d).", id, c->type); | |
719fc62f | 1793 | channel_free(c); |
7368a6c8 | 1794 | } |
8efc0c15 | 1795 | |
6ae2364d | 1796 | void |
188adeb2 | 1797 | channel_input_open_confirmation(int type, int plen, void *ctxt) |
8efc0c15 | 1798 | { |
7368a6c8 | 1799 | int id, remote_id; |
1800 | Channel *c; | |
5260325f | 1801 | |
7e7327a1 | 1802 | if (!compat20) |
1803 | packet_integrity_check(plen, 4 + 4, type); | |
5260325f | 1804 | |
7368a6c8 | 1805 | id = packet_get_int(); |
1806 | c = channel_lookup(id); | |
5260325f | 1807 | |
7368a6c8 | 1808 | if (c==NULL || c->type != SSH_CHANNEL_OPENING) |
1809 | packet_disconnect("Received open confirmation for " | |
1810 | "non-opening channel %d.", id); | |
1811 | remote_id = packet_get_int(); | |
aa3378df | 1812 | /* Record the remote channel number and mark that the channel is now open. */ |
7368a6c8 | 1813 | c->remote_id = remote_id; |
1814 | c->type = SSH_CHANNEL_OPEN; | |
7e7327a1 | 1815 | |
1816 | if (compat20) { | |
1817 | c->remote_window = packet_get_int(); | |
1818 | c->remote_maxpacket = packet_get_int(); | |
6ae2364d | 1819 | packet_done(); |
7e7327a1 | 1820 | if (c->cb_fn != NULL && c->cb_event == type) { |
de273eef | 1821 | debug2("callback start"); |
7e7327a1 | 1822 | c->cb_fn(c->self, c->cb_arg); |
de273eef | 1823 | debug2("callback done"); |
7e7327a1 | 1824 | } |
1825 | debug("channel %d: open confirm rwindow %d rmax %d", c->self, | |
1826 | c->remote_window, c->remote_maxpacket); | |
1827 | } | |
8efc0c15 | 1828 | } |
1829 | ||
396c147e | 1830 | static char * |
d18e0850 | 1831 | reason2txt(int reason) |
1832 | { | |
1833 | switch(reason) { | |
1834 | case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED: | |
1835 | return "administratively prohibited"; | |
1836 | case SSH2_OPEN_CONNECT_FAILED: | |
1837 | return "connect failed"; | |
1838 | case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE: | |
1839 | return "unknown channel type"; | |
1840 | case SSH2_OPEN_RESOURCE_SHORTAGE: | |
1841 | return "resource shortage"; | |
1842 | } | |
7e8c18e9 | 1843 | return "unknown reason"; |
d18e0850 | 1844 | } |
1845 | ||
6ae2364d | 1846 | void |
188adeb2 | 1847 | channel_input_open_failure(int type, int plen, void *ctxt) |
8efc0c15 | 1848 | { |
02a024dd | 1849 | int id, reason; |
1850 | char *msg = NULL, *lang = NULL; | |
7368a6c8 | 1851 | Channel *c; |
5260325f | 1852 | |
7e7327a1 | 1853 | if (!compat20) |
1854 | packet_integrity_check(plen, 4, type); | |
7368a6c8 | 1855 | |
1856 | id = packet_get_int(); | |
1857 | c = channel_lookup(id); | |
1858 | ||
1859 | if (c==NULL || c->type != SSH_CHANNEL_OPENING) | |
1860 | packet_disconnect("Received open failure for " | |
1861 | "non-opening channel %d.", id); | |
7e7327a1 | 1862 | if (compat20) { |
02a024dd | 1863 | reason = packet_get_int(); |
fbe90f7b | 1864 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { |
02a024dd | 1865 | msg = packet_get_string(NULL); |
1866 | lang = packet_get_string(NULL); | |
1867 | } | |
6ae2364d | 1868 | packet_done(); |
d18e0850 | 1869 | log("channel %d: open failed: %s%s%s", id, |
1870 | reason2txt(reason), msg ? ": ": "", msg ? msg : ""); | |
02a024dd | 1871 | if (msg != NULL) |
1872 | xfree(msg); | |
1873 | if (lang != NULL) | |
1874 | xfree(lang); | |
7e7327a1 | 1875 | } |
5260325f | 1876 | /* Free the channel. This will also close the socket. */ |
719fc62f | 1877 | channel_free(c); |
8efc0c15 | 1878 | } |
1879 | ||
7e7327a1 | 1880 | void |
188adeb2 | 1881 | channel_input_channel_request(int type, int plen, void *ctxt) |
7e7327a1 | 1882 | { |
1883 | int id; | |
1884 | Channel *c; | |
1885 | ||
1886 | id = packet_get_int(); | |
1887 | c = channel_lookup(id); | |
1888 | ||
1889 | if (c == NULL || | |
1890 | (c->type != SSH_CHANNEL_OPEN && c->type != SSH_CHANNEL_LARVAL)) | |
1891 | packet_disconnect("Received request for " | |
1892 | "non-open channel %d.", id); | |
1893 | if (c->cb_fn != NULL && c->cb_event == type) { | |
de273eef | 1894 | debug2("callback start"); |
7e7327a1 | 1895 | c->cb_fn(c->self, c->cb_arg); |
de273eef | 1896 | debug2("callback done"); |
8e7895b8 | 1897 | } else { |
1898 | char *service = packet_get_string(NULL); | |
1899 | debug("channel %d: rcvd request for %s", c->self, service); | |
1900 | debug("cb_fn %p cb_event %d", c->cb_fn , c->cb_event); | |
1901 | xfree(service); | |
719fc62f | 1902 | } |
3ffc6336 | 1903 | } |
1904 | ||
8e7895b8 | 1905 | void |
1906 | channel_input_window_adjust(int type, int plen, void *ctxt) | |
1907 | { | |
1908 | Channel *c; | |
1909 | int id, adjust; | |
3ffc6336 | 1910 | |
8e7895b8 | 1911 | if (!compat20) |
1912 | return; | |
8efc0c15 | 1913 | |
8e7895b8 | 1914 | /* Get the channel number and verify it. */ |
1915 | id = packet_get_int(); | |
1916 | c = channel_lookup(id); | |
1917 | ||
1918 | if (c == NULL || c->type != SSH_CHANNEL_OPEN) { | |
1919 | log("Received window adjust for " | |
1920 | "non-open channel %d.", id); | |
1921 | return; | |
1922 | } | |
1923 | adjust = packet_get_int(); | |
1924 | packet_done(); | |
1925 | debug2("channel %d: rcvd adjust %d", id, adjust); | |
1926 | c->remote_window += adjust; | |
1927 | } | |
1928 | ||
1929 | void | |
1930 | channel_input_port_open(int type, int plen, void *ctxt) | |
8efc0c15 | 1931 | { |
8e7895b8 | 1932 | Channel *c = NULL; |
1933 | u_short host_port; | |
1934 | char *host, *originator_string; | |
1935 | int remote_id, sock = -1; | |
5260325f | 1936 | |
8e7895b8 | 1937 | remote_id = packet_get_int(); |
1938 | host = packet_get_string(NULL); | |
1939 | host_port = packet_get_int(); | |
1940 | ||
1941 | if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) { | |
1942 | originator_string = packet_get_string(NULL); | |
1943 | } else { | |
1944 | originator_string = xstrdup("unknown (remote did not supply name)"); | |
1945 | } | |
1946 | packet_done(); | |
1947 | sock = channel_connect_to(host, host_port); | |
1948 | if (sock != -1) { | |
1949 | c = channel_new("connected socket", | |
1950 | SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0, | |
1951 | originator_string, 1); | |
1952 | if (c == NULL) { | |
1953 | error("channel_input_port_open: channel_new failed"); | |
1954 | close(sock); | |
1955 | } else { | |
1956 | c->remote_id = remote_id; | |
5260325f | 1957 | } |
1958 | } | |
8e7895b8 | 1959 | if (c == NULL) { |
1960 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
1961 | packet_put_int(remote_id); | |
1962 | packet_send(); | |
1963 | } | |
1964 | xfree(host); | |
8efc0c15 | 1965 | } |
1966 | ||
8e7895b8 | 1967 | |
1968 | /* -- tcp forwarding */ | |
1969 | ||
aa3378df | 1970 | /* |
1971 | * Initiate forwarding of connections to local port "port" through the secure | |
1972 | * channel to host:port from remote side. | |
1973 | */ | |
02a024dd | 1974 | int |
fa08c86b | 1975 | channel_request_local_forwarding(u_short listen_port, const char *host_to_connect, |
1976 | u_short port_to_connect, int gateway_ports) | |
1977 | { | |
02a024dd | 1978 | return channel_request_forwarding( |
fa08c86b | 1979 | NULL, listen_port, |
1980 | host_to_connect, port_to_connect, | |
1981 | gateway_ports, /*remote_fwd*/ 0); | |
1982 | } | |
8efc0c15 | 1983 | |
fa08c86b | 1984 | /* |
1985 | * If 'remote_fwd' is true we have a '-R style' listener for protocol 2 | |
1986 | * (SSH_CHANNEL_RPORT_LISTENER). | |
1987 | */ | |
02a024dd | 1988 | int |
fa08c86b | 1989 | channel_request_forwarding( |
1990 | const char *listen_address, u_short listen_port, | |
1991 | const char *host_to_connect, u_short port_to_connect, | |
1992 | int gateway_ports, int remote_fwd) | |
8efc0c15 | 1993 | { |
719fc62f | 1994 | Channel *c; |
8e7895b8 | 1995 | int success, sock, on = 1, type; |
48e671d5 | 1996 | struct addrinfo hints, *ai, *aitop; |
1997 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; | |
fa08c86b | 1998 | const char *host; |
aa3378df | 1999 | struct linger linger; |
5260325f | 2000 | |
02a024dd | 2001 | success = 0; |
2002 | ||
fa08c86b | 2003 | if (remote_fwd) { |
2004 | host = listen_address; | |
8e7895b8 | 2005 | type = SSH_CHANNEL_RPORT_LISTENER; |
fa08c86b | 2006 | } else { |
2007 | host = host_to_connect; | |
8e7895b8 | 2008 | type = SSH_CHANNEL_PORT_LISTENER; |
fa08c86b | 2009 | } |
2010 | ||
719fc62f | 2011 | if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) { |
02a024dd | 2012 | error("Forward host name too long."); |
2013 | return success; | |
2014 | } | |
5260325f | 2015 | |
fa08c86b | 2016 | /* XXX listen_address is currently ignored */ |
aa3378df | 2017 | /* |
48e671d5 | 2018 | * getaddrinfo returns a loopback address if the hostname is |
2019 | * set to NULL and hints.ai_flags is not AI_PASSIVE | |
aa3378df | 2020 | */ |
48e671d5 | 2021 | memset(&hints, 0, sizeof(hints)); |
2022 | hints.ai_family = IPv4or6; | |
2023 | hints.ai_flags = gateway_ports ? AI_PASSIVE : 0; | |
2024 | hints.ai_socktype = SOCK_STREAM; | |
fa08c86b | 2025 | snprintf(strport, sizeof strport, "%d", listen_port); |
48e671d5 | 2026 | if (getaddrinfo(NULL, strport, &hints, &aitop) != 0) |
2027 | packet_disconnect("getaddrinfo: fatal error"); | |
2028 | ||
48e671d5 | 2029 | for (ai = aitop; ai; ai = ai->ai_next) { |
2030 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2031 | continue; | |
2032 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), | |
2033 | strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
fa08c86b | 2034 | error("channel_request_forwarding: getnameinfo failed"); |
48e671d5 | 2035 | continue; |
2036 | } | |
2037 | /* Create a port to listen for the host. */ | |
2038 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
2039 | if (sock < 0) { | |
2040 | /* this is no error since kernel may not support ipv6 */ | |
2041 | verbose("socket: %.100s", strerror(errno)); | |
2042 | continue; | |
2043 | } | |
2044 | /* | |
2045 | * Set socket options. We would like the socket to disappear | |
2046 | * as soon as it has been closed for whatever reason. | |
2047 | */ | |
2048 | setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on)); | |
2049 | linger.l_onoff = 1; | |
2050 | linger.l_linger = 5; | |
2051 | setsockopt(sock, SOL_SOCKET, SO_LINGER, (void *)&linger, sizeof(linger)); | |
2052 | debug("Local forwarding listening on %s port %s.", ntop, strport); | |
2053 | ||
2054 | /* Bind the socket to the address. */ | |
2055 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
2056 | /* address can be in use ipv6 address is already bound */ | |
16218745 | 2057 | if (!ai->ai_next) |
2058 | error("bind: %.100s", strerror(errno)); | |
2059 | else | |
2060 | verbose("bind: %.100s", strerror(errno)); | |
2b87da3b | 2061 | |
48e671d5 | 2062 | close(sock); |
2063 | continue; | |
2064 | } | |
2065 | /* Start listening for connections on the socket. */ | |
2066 | if (listen(sock, 5) < 0) { | |
2067 | error("listen: %.100s", strerror(errno)); | |
2068 | close(sock); | |
2069 | continue; | |
2070 | } | |
2071 | /* Allocate a channel number for the socket. */ | |
8e7895b8 | 2072 | c = channel_new("port listener", type, sock, sock, -1, |
0b242b12 | 2073 | CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, |
a22aff1f | 2074 | 0, xstrdup("port listener"), 1); |
719fc62f | 2075 | if (c == NULL) { |
2076 | error("channel_request_forwarding: channel_new failed"); | |
2077 | close(sock); | |
2078 | continue; | |
2079 | } | |
2080 | strlcpy(c->path, host, sizeof(c->path)); | |
2081 | c->host_port = port_to_connect; | |
2082 | c->listening_port = listen_port; | |
48e671d5 | 2083 | success = 1; |
2084 | } | |
2085 | if (success == 0) | |
02a024dd | 2086 | error("channel_request_forwarding: cannot listen to port: %d", |
2087 | listen_port); | |
48e671d5 | 2088 | freeaddrinfo(aitop); |
02a024dd | 2089 | return success; |
5260325f | 2090 | } |
8efc0c15 | 2091 | |
aa3378df | 2092 | /* |
2093 | * Initiate forwarding of connections to port "port" on remote host through | |
2094 | * the secure channel to host:port from local side. | |
2095 | */ | |
8efc0c15 | 2096 | |
6ae2364d | 2097 | void |
fa08c86b | 2098 | channel_request_remote_forwarding(u_short listen_port, |
2099 | const char *host_to_connect, u_short port_to_connect) | |
8efc0c15 | 2100 | { |
fa08c86b | 2101 | int payload_len, type, success = 0; |
2102 | ||
5260325f | 2103 | /* Record locally that connection to this host/port is permitted. */ |
2104 | if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION) | |
2105 | fatal("channel_request_remote_forwarding: too many forwards"); | |
2106 | ||
5260325f | 2107 | /* Send the forward request to the remote side. */ |
7e7327a1 | 2108 | if (compat20) { |
2109 | const char *address_to_bind = "0.0.0.0"; | |
2110 | packet_start(SSH2_MSG_GLOBAL_REQUEST); | |
2111 | packet_put_cstring("tcpip-forward"); | |
2112 | packet_put_char(0); /* boolean: want reply */ | |
2113 | packet_put_cstring(address_to_bind); | |
2114 | packet_put_int(listen_port); | |
fa08c86b | 2115 | packet_send(); |
2116 | packet_write_wait(); | |
2117 | /* Assume that server accepts the request */ | |
2118 | success = 1; | |
7e7327a1 | 2119 | } else { |
2120 | packet_start(SSH_CMSG_PORT_FORWARD_REQUEST); | |
7e7327a1 | 2121 | packet_put_int(listen_port); |
d6f24e45 | 2122 | packet_put_cstring(host_to_connect); |
2123 | packet_put_int(port_to_connect); | |
7e7327a1 | 2124 | packet_send(); |
2125 | packet_write_wait(); | |
fa08c86b | 2126 | |
2127 | /* Wait for response from the remote side. */ | |
2128 | type = packet_read(&payload_len); | |
2129 | switch (type) { | |
2130 | case SSH_SMSG_SUCCESS: | |
2131 | success = 1; | |
2132 | break; | |
2133 | case SSH_SMSG_FAILURE: | |
2134 | log("Warning: Server denied remote port forwarding."); | |
2135 | break; | |
2136 | default: | |
2137 | /* Unknown packet */ | |
2138 | packet_disconnect("Protocol error for port forward request:" | |
2139 | "received packet type %d.", type); | |
2140 | } | |
2141 | } | |
2142 | if (success) { | |
2143 | permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect); | |
2144 | permitted_opens[num_permitted_opens].port_to_connect = port_to_connect; | |
2145 | permitted_opens[num_permitted_opens].listen_port = listen_port; | |
2146 | num_permitted_opens++; | |
7e7327a1 | 2147 | } |
8efc0c15 | 2148 | } |
2149 | ||
aa3378df | 2150 | /* |
2151 | * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates | |
2152 | * listening for the port, and sends back a success reply (or disconnect | |
2153 | * message if there was an error). This never returns if there was an error. | |
2154 | */ | |
8efc0c15 | 2155 | |
6ae2364d | 2156 | void |
1d1ffb87 | 2157 | channel_input_port_forward_request(int is_root, int gateway_ports) |
8efc0c15 | 2158 | { |
57112b5a | 2159 | u_short port, host_port; |
5260325f | 2160 | char *hostname; |
2161 | ||
2162 | /* Get arguments from the packet. */ | |
2163 | port = packet_get_int(); | |
2164 | hostname = packet_get_string(NULL); | |
2165 | host_port = packet_get_int(); | |
2166 | ||
3c62e7eb | 2167 | #ifndef HAVE_CYGWIN |
aa3378df | 2168 | /* |
2169 | * Check that an unprivileged user is not trying to forward a | |
2170 | * privileged port. | |
2171 | */ | |
5260325f | 2172 | if (port < IPPORT_RESERVED && !is_root) |
2173 | packet_disconnect("Requested forwarding of port %d but user is not root.", | |
2174 | port); | |
3c62e7eb | 2175 | #endif |
fa08c86b | 2176 | /* Initiate forwarding */ |
1d1ffb87 | 2177 | channel_request_local_forwarding(port, hostname, host_port, gateway_ports); |
5260325f | 2178 | |
2179 | /* Free the argument string. */ | |
2180 | xfree(hostname); | |
8efc0c15 | 2181 | } |
2182 | ||
01794848 | 2183 | /* |
2184 | * Permits opening to any host/port if permitted_opens[] is empty. This is | |
2185 | * usually called by the server, because the user could connect to any port | |
2186 | * anyway, and the server has no way to know but to trust the client anyway. | |
2187 | */ | |
2188 | void | |
2189 | channel_permit_all_opens() | |
2190 | { | |
2191 | if (num_permitted_opens == 0) | |
2192 | all_opens_permitted = 1; | |
2193 | } | |
2194 | ||
cd332296 | 2195 | void |
01794848 | 2196 | channel_add_permitted_opens(char *host, int port) |
2197 | { | |
2198 | if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION) | |
2199 | fatal("channel_request_remote_forwarding: too many forwards"); | |
2200 | debug("allow port forwarding to host %s port %d", host, port); | |
2201 | ||
2202 | permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host); | |
2203 | permitted_opens[num_permitted_opens].port_to_connect = port; | |
2204 | num_permitted_opens++; | |
2205 | ||
2206 | all_opens_permitted = 0; | |
2207 | } | |
2208 | ||
cd332296 | 2209 | void |
01794848 | 2210 | channel_clear_permitted_opens(void) |
2211 | { | |
2212 | int i; | |
2213 | ||
2214 | for (i = 0; i < num_permitted_opens; i++) | |
2215 | xfree(permitted_opens[i].host_to_connect); | |
2216 | num_permitted_opens = 0; | |
2217 | ||
2218 | } | |
2219 | ||
2220 | ||
2221 | /* return socket to remote host, port */ | |
396c147e | 2222 | static int |
01794848 | 2223 | connect_to(const char *host, u_short port) |
8efc0c15 | 2224 | { |
48e671d5 | 2225 | struct addrinfo hints, *ai, *aitop; |
2226 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; | |
2227 | int gaierr; | |
7368a6c8 | 2228 | int sock = -1; |
48e671d5 | 2229 | |
2230 | memset(&hints, 0, sizeof(hints)); | |
2231 | hints.ai_family = IPv4or6; | |
2232 | hints.ai_socktype = SOCK_STREAM; | |
01794848 | 2233 | snprintf(strport, sizeof strport, "%d", port); |
48e671d5 | 2234 | if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) { |
01794848 | 2235 | error("connect_to %.100s: unknown host (%s)", host, |
2236 | gai_strerror(gaierr)); | |
7368a6c8 | 2237 | return -1; |
48e671d5 | 2238 | } |
48e671d5 | 2239 | for (ai = aitop; ai; ai = ai->ai_next) { |
2240 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2241 | continue; | |
2242 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), | |
2243 | strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
01794848 | 2244 | error("connect_to: getnameinfo failed"); |
48e671d5 | 2245 | continue; |
5260325f | 2246 | } |
48e671d5 | 2247 | sock = socket(ai->ai_family, SOCK_STREAM, 0); |
2248 | if (sock < 0) { | |
2249 | error("socket: %.100s", strerror(errno)); | |
2250 | continue; | |
5260325f | 2251 | } |
eea39c02 | 2252 | if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0) |
97fb6912 | 2253 | fatal("connect_to: F_SETFL: %s", strerror(errno)); |
97fb6912 | 2254 | if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 && |
2255 | errno != EINPROGRESS) { | |
01794848 | 2256 | error("connect_to %.100s port %s: %.100s", ntop, strport, |
48e671d5 | 2257 | strerror(errno)); |
2258 | close(sock); | |
2b87da3b | 2259 | continue; /* fail -- try next */ |
48e671d5 | 2260 | } |
2261 | break; /* success */ | |
5260325f | 2262 | |
5260325f | 2263 | } |
48e671d5 | 2264 | freeaddrinfo(aitop); |
48e671d5 | 2265 | if (!ai) { |
01794848 | 2266 | error("connect_to %.100s port %d: failed.", host, port); |
7368a6c8 | 2267 | return -1; |
8efc0c15 | 2268 | } |
7368a6c8 | 2269 | /* success */ |
2270 | return sock; | |
2271 | } | |
01794848 | 2272 | |
fa08c86b | 2273 | int |
2274 | channel_connect_by_listen_adress(u_short listen_port) | |
2275 | { | |
2276 | int i; | |
01794848 | 2277 | |
fa08c86b | 2278 | for (i = 0; i < num_permitted_opens; i++) |
2279 | if (permitted_opens[i].listen_port == listen_port) | |
01794848 | 2280 | return connect_to( |
fa08c86b | 2281 | permitted_opens[i].host_to_connect, |
2282 | permitted_opens[i].port_to_connect); | |
0b6fbf03 | 2283 | error("WARNING: Server requests forwarding for unknown listen_port %d", |
2284 | listen_port); | |
fa08c86b | 2285 | return -1; |
2286 | } | |
48e671d5 | 2287 | |
01794848 | 2288 | /* Check if connecting to that port is permitted and connect. */ |
2289 | int | |
2290 | channel_connect_to(const char *host, u_short port) | |
2291 | { | |
2292 | int i, permit; | |
2293 | ||
2294 | permit = all_opens_permitted; | |
2295 | if (!permit) { | |
2296 | for (i = 0; i < num_permitted_opens; i++) | |
2297 | if (permitted_opens[i].port_to_connect == port && | |
2298 | strcmp(permitted_opens[i].host_to_connect, host) == 0) | |
2299 | permit = 1; | |
2300 | ||
2301 | } | |
2302 | if (!permit) { | |
2303 | log("Received request to connect to host %.100s port %d, " | |
2304 | "but the request was denied.", host, port); | |
2305 | return -1; | |
2306 | } | |
2307 | return connect_to(host, port); | |
2308 | } | |
2309 | ||
8e7895b8 | 2310 | /* -- X11 forwarding */ |
8efc0c15 | 2311 | |
aa3378df | 2312 | /* |
2313 | * Creates an internet domain socket for listening for X11 connections. | |
2314 | * Returns a suitable value for the DISPLAY variable, or NULL if an error | |
2315 | * occurs. | |
2316 | */ | |
5260325f | 2317 | char * |
95f1eccc | 2318 | x11_create_display_inet(int screen_number, int x11_display_offset) |
8efc0c15 | 2319 | { |
57112b5a | 2320 | int display_number, sock; |
2321 | u_short port; | |
48e671d5 | 2322 | struct addrinfo hints, *ai, *aitop; |
2323 | char strport[NI_MAXSERV]; | |
2324 | int gaierr, n, num_socks = 0, socks[NUM_SOCKS]; | |
2325 | char display[512]; | |
5260325f | 2326 | char hostname[MAXHOSTNAMELEN]; |
2327 | ||
95f1eccc | 2328 | for (display_number = x11_display_offset; |
5260325f | 2329 | display_number < MAX_DISPLAYS; |
2330 | display_number++) { | |
2331 | port = 6000 + display_number; | |
48e671d5 | 2332 | memset(&hints, 0, sizeof(hints)); |
2333 | hints.ai_family = IPv4or6; | |
2334 | hints.ai_flags = AI_PASSIVE; /* XXX loopback only ? */ | |
2335 | hints.ai_socktype = SOCK_STREAM; | |
2336 | snprintf(strport, sizeof strport, "%d", port); | |
2337 | if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) { | |
2338 | error("getaddrinfo: %.100s", gai_strerror(gaierr)); | |
5260325f | 2339 | return NULL; |
2340 | } | |
48e671d5 | 2341 | for (ai = aitop; ai; ai = ai->ai_next) { |
2342 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2343 | continue; | |
2344 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
2345 | if (sock < 0) { | |
4ee81249 | 2346 | if ((errno != EINVAL) && (errno != EAFNOSUPPORT)) { |
80a44451 | 2347 | error("socket: %.100s", strerror(errno)); |
2348 | return NULL; | |
2349 | } else { | |
22d89d24 | 2350 | debug("x11_create_display_inet: Socket family %d not supported", |
2351 | ai->ai_family); | |
80a44451 | 2352 | continue; |
2353 | } | |
48e671d5 | 2354 | } |
2355 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
2356 | debug("bind port %d: %.100s", port, strerror(errno)); | |
2357 | shutdown(sock, SHUT_RDWR); | |
2358 | close(sock); | |
16218745 | 2359 | |
2360 | if (ai->ai_next) | |
2361 | continue; | |
2362 | ||
48e671d5 | 2363 | for (n = 0; n < num_socks; n++) { |
2364 | shutdown(socks[n], SHUT_RDWR); | |
2365 | close(socks[n]); | |
2366 | } | |
2367 | num_socks = 0; | |
2368 | break; | |
2369 | } | |
2370 | socks[num_socks++] = sock; | |
80faa19f | 2371 | #ifndef DONT_TRY_OTHER_AF |
48e671d5 | 2372 | if (num_socks == NUM_SOCKS) |
2373 | break; | |
80faa19f | 2374 | #else |
2375 | break; | |
2376 | #endif | |
5260325f | 2377 | } |
4ccb01d6 | 2378 | freeaddrinfo(aitop); |
48e671d5 | 2379 | if (num_socks > 0) |
2380 | break; | |
5260325f | 2381 | } |
2382 | if (display_number >= MAX_DISPLAYS) { | |
2383 | error("Failed to allocate internet-domain X11 display socket."); | |
2384 | return NULL; | |
8efc0c15 | 2385 | } |
5260325f | 2386 | /* Start listening for connections on the socket. */ |
48e671d5 | 2387 | for (n = 0; n < num_socks; n++) { |
2388 | sock = socks[n]; | |
2389 | if (listen(sock, 5) < 0) { | |
2390 | error("listen: %.100s", strerror(errno)); | |
2391 | shutdown(sock, SHUT_RDWR); | |
2392 | close(sock); | |
2393 | return NULL; | |
2394 | } | |
8efc0c15 | 2395 | } |
48e671d5 | 2396 | |
5260325f | 2397 | /* Set up a suitable value for the DISPLAY variable. */ |
2398 | if (gethostname(hostname, sizeof(hostname)) < 0) | |
2399 | fatal("gethostname: %.100s", strerror(errno)); | |
a7effaac | 2400 | |
2401 | #ifdef IPADDR_IN_DISPLAY | |
2b87da3b | 2402 | /* |
a7effaac | 2403 | * HPUX detects the local hostname in the DISPLAY variable and tries |
2404 | * to set up a shared memory connection to the server, which it | |
2405 | * incorrectly supposes to be local. | |
2406 | * | |
2407 | * The workaround - as used in later $$H and other programs - is | |
2408 | * is to set display to the host's IP address. | |
2409 | */ | |
2410 | { | |
2411 | struct hostent *he; | |
2412 | struct in_addr my_addr; | |
2413 | ||
2414 | he = gethostbyname(hostname); | |
2415 | if (he == NULL) { | |
2416 | error("[X11-broken-fwd-hostname-workaround] Could not get " | |
2417 | "IP address for hostname %s.", hostname); | |
2418 | ||
2419 | packet_send_debug("[X11-broken-fwd-hostname-workaround]" | |
2420 | "Could not get IP address for hostname %s.", hostname); | |
2421 | ||
2422 | shutdown(sock, SHUT_RDWR); | |
2423 | close(sock); | |
2424 | ||
2425 | return NULL; | |
2426 | } | |
2427 | ||
2428 | memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr)); | |
2429 | ||
2430 | /* Set DISPLAY to <ip address>:screen.display */ | |
2b87da3b | 2431 | snprintf(display, sizeof(display), "%.50s:%d.%d", inet_ntoa(my_addr), |
74141647 | 2432 | display_number, screen_number); |
a7effaac | 2433 | } |
2434 | #else /* IPADDR_IN_DISPLAY */ | |
2435 | /* Just set DISPLAY to hostname:screen.display */ | |
48e671d5 | 2436 | snprintf(display, sizeof display, "%.400s:%d.%d", hostname, |
74141647 | 2437 | display_number, screen_number); |
a7effaac | 2438 | #endif /* IPADDR_IN_DISPLAY */ |
5260325f | 2439 | |
48e671d5 | 2440 | /* Allocate a channel for each socket. */ |
2441 | for (n = 0; n < num_socks; n++) { | |
2442 | sock = socks[n]; | |
0b242b12 | 2443 | (void) channel_new("x11 listener", |
2444 | SSH_CHANNEL_X11_LISTENER, sock, sock, -1, | |
2445 | CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, | |
a22aff1f | 2446 | 0, xstrdup("X11 inet listener"), 1); |
48e671d5 | 2447 | } |
5260325f | 2448 | |
2449 | /* Return a suitable value for the DISPLAY environment variable. */ | |
48e671d5 | 2450 | return xstrdup(display); |
8efc0c15 | 2451 | } |
2452 | ||
2453 | #ifndef X_UNIX_PATH | |
2454 | #define X_UNIX_PATH "/tmp/.X11-unix/X" | |
2455 | #endif | |
2456 | ||
396c147e | 2457 | static int |
1e3b8b07 | 2458 | connect_local_xsocket(u_int dnr) |
8efc0c15 | 2459 | { |
5260325f | 2460 | static const char *const x_sockets[] = { |
2461 | X_UNIX_PATH "%u", | |
2462 | "/var/X/.X11-unix/X" "%u", | |
2463 | "/usr/spool/sockets/X11/" "%u", | |
2464 | NULL | |
2465 | }; | |
2466 | int sock; | |
2467 | struct sockaddr_un addr; | |
2468 | const char *const * path; | |
2469 | ||
2470 | for (path = x_sockets; *path; ++path) { | |
2471 | sock = socket(AF_UNIX, SOCK_STREAM, 0); | |
2472 | if (sock < 0) | |
2473 | error("socket: %.100s", strerror(errno)); | |
2474 | memset(&addr, 0, sizeof(addr)); | |
2475 | addr.sun_family = AF_UNIX; | |
2476 | snprintf(addr.sun_path, sizeof addr.sun_path, *path, dnr); | |
2477 | if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0) | |
2478 | return sock; | |
2479 | close(sock); | |
2480 | } | |
2481 | error("connect %.100s: %.100s", addr.sun_path, strerror(errno)); | |
2482 | return -1; | |
8efc0c15 | 2483 | } |
2484 | ||
0b242b12 | 2485 | int |
2486 | x11_connect_display(void) | |
8efc0c15 | 2487 | { |
0b242b12 | 2488 | int display_number, sock = 0; |
5260325f | 2489 | const char *display; |
0b242b12 | 2490 | char buf[1024], *cp; |
48e671d5 | 2491 | struct addrinfo hints, *ai, *aitop; |
2492 | char strport[NI_MAXSERV]; | |
2493 | int gaierr; | |
5260325f | 2494 | |
5260325f | 2495 | /* Try to open a socket for the local X server. */ |
2496 | display = getenv("DISPLAY"); | |
2497 | if (!display) { | |
2498 | error("DISPLAY not set."); | |
0b242b12 | 2499 | return -1; |
5260325f | 2500 | } |
aa3378df | 2501 | /* |
2502 | * Now we decode the value of the DISPLAY variable and make a | |
2503 | * connection to the real X server. | |
2504 | */ | |
2505 | ||
2506 | /* | |
2507 | * Check if it is a unix domain socket. Unix domain displays are in | |
2508 | * one of the following formats: unix:d[.s], :d[.s], ::d[.s] | |
2509 | */ | |
5260325f | 2510 | if (strncmp(display, "unix:", 5) == 0 || |
2511 | display[0] == ':') { | |
2512 | /* Connect to the unix domain socket. */ | |
2513 | if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) { | |
2514 | error("Could not parse display number from DISPLAY: %.100s", | |
2515 | display); | |
0b242b12 | 2516 | return -1; |
5260325f | 2517 | } |
2518 | /* Create a socket. */ | |
2519 | sock = connect_local_xsocket(display_number); | |
2520 | if (sock < 0) | |
0b242b12 | 2521 | return -1; |
5260325f | 2522 | |
2523 | /* OK, we now have a connection to the display. */ | |
0b242b12 | 2524 | return sock; |
5260325f | 2525 | } |
aa3378df | 2526 | /* |
2527 | * Connect to an inet socket. The DISPLAY value is supposedly | |
2528 | * hostname:d[.s], where hostname may also be numeric IP address. | |
2529 | */ | |
5260325f | 2530 | strncpy(buf, display, sizeof(buf)); |
2531 | buf[sizeof(buf) - 1] = 0; | |
2532 | cp = strchr(buf, ':'); | |
2533 | if (!cp) { | |
2534 | error("Could not find ':' in DISPLAY: %.100s", display); | |
0b242b12 | 2535 | return -1; |
5260325f | 2536 | } |
2537 | *cp = 0; | |
aa3378df | 2538 | /* buf now contains the host name. But first we parse the display number. */ |
5260325f | 2539 | if (sscanf(cp + 1, "%d", &display_number) != 1) { |
2540 | error("Could not parse display number from DISPLAY: %.100s", | |
2541 | display); | |
0b242b12 | 2542 | return -1; |
5260325f | 2543 | } |
5260325f | 2544 | |
48e671d5 | 2545 | /* Look up the host address */ |
2546 | memset(&hints, 0, sizeof(hints)); | |
2547 | hints.ai_family = IPv4or6; | |
2548 | hints.ai_socktype = SOCK_STREAM; | |
2549 | snprintf(strport, sizeof strport, "%d", 6000 + display_number); | |
2550 | if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) { | |
2551 | error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr)); | |
0b242b12 | 2552 | return -1; |
8efc0c15 | 2553 | } |
48e671d5 | 2554 | for (ai = aitop; ai; ai = ai->ai_next) { |
2555 | /* Create a socket. */ | |
2556 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
2557 | if (sock < 0) { | |
2558 | debug("socket: %.100s", strerror(errno)); | |
7368a6c8 | 2559 | continue; |
2560 | } | |
2561 | /* Connect it to the display. */ | |
2562 | if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
2563 | debug("connect %.100s port %d: %.100s", buf, | |
2564 | 6000 + display_number, strerror(errno)); | |
2565 | close(sock); | |
2566 | continue; | |
2567 | } | |
2568 | /* Success */ | |
2569 | break; | |
48e671d5 | 2570 | } |
48e671d5 | 2571 | freeaddrinfo(aitop); |
2572 | if (!ai) { | |
6ae2364d | 2573 | error("connect %.100s port %d: %.100s", buf, 6000 + display_number, |
48e671d5 | 2574 | strerror(errno)); |
0b242b12 | 2575 | return -1; |
8efc0c15 | 2576 | } |
0b242b12 | 2577 | return sock; |
2578 | } | |
5260325f | 2579 | |
0b242b12 | 2580 | /* |
2581 | * This is called when SSH_SMSG_X11_OPEN is received. The packet contains | |
2582 | * the remote channel number. We should do whatever we want, and respond | |
2583 | * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE. | |
2584 | */ | |
5260325f | 2585 | |
0b242b12 | 2586 | void |
188adeb2 | 2587 | x11_input_open(int type, int plen, void *ctxt) |
0b242b12 | 2588 | { |
719fc62f | 2589 | Channel *c = NULL; |
2590 | int remote_id, sock = 0; | |
0b242b12 | 2591 | char *remote_host; |
5260325f | 2592 | |
719fc62f | 2593 | debug("Received X11 open request."); |
5260325f | 2594 | |
719fc62f | 2595 | remote_id = packet_get_int(); |
8e7895b8 | 2596 | |
2597 | if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) { | |
719fc62f | 2598 | remote_host = packet_get_string(NULL); |
0b242b12 | 2599 | } else { |
2600 | remote_host = xstrdup("unknown (remote did not supply name)"); | |
0b242b12 | 2601 | } |
719fc62f | 2602 | packet_done(); |
0b242b12 | 2603 | |
2604 | /* Obtain a connection to the real X display. */ | |
2605 | sock = x11_connect_display(); | |
719fc62f | 2606 | if (sock != -1) { |
2607 | /* Allocate a channel for this connection. */ | |
2608 | c = channel_new("connected x11 socket", | |
2609 | SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0, | |
2610 | remote_host, 1); | |
2611 | if (c == NULL) { | |
2612 | error("x11_input_open: channel_new failed"); | |
2613 | close(sock); | |
2614 | } else { | |
2615 | c->remote_id = remote_id; | |
2616 | } | |
2617 | } | |
2618 | if (c == NULL) { | |
0b242b12 | 2619 | /* Send refusal to the remote host. */ |
2620 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
719fc62f | 2621 | packet_put_int(remote_id); |
0b242b12 | 2622 | } else { |
0b242b12 | 2623 | /* Send a confirmation to the remote host. */ |
2624 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
719fc62f | 2625 | packet_put_int(remote_id); |
2626 | packet_put_int(c->self); | |
0b242b12 | 2627 | } |
719fc62f | 2628 | packet_send(); |
8efc0c15 | 2629 | } |
2630 | ||
a22aff1f | 2631 | /* dummy protocol handler that denies SSH-1 requests (agent/x11) */ |
2632 | void | |
2633 | deny_input_open(int type, int plen, void *ctxt) | |
2634 | { | |
2635 | int rchan = packet_get_int(); | |
2636 | switch(type){ | |
2637 | case SSH_SMSG_AGENT_OPEN: | |
2638 | error("Warning: ssh server tried agent forwarding."); | |
2639 | break; | |
2640 | case SSH_SMSG_X11_OPEN: | |
2641 | error("Warning: ssh server tried X11 forwarding."); | |
2642 | break; | |
2643 | default: | |
2644 | error("deny_input_open: type %d plen %d", type, plen); | |
2645 | break; | |
2646 | } | |
2647 | error("Warning: this is probably a break in attempt by a malicious server."); | |
2648 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
2649 | packet_put_int(rchan); | |
2650 | packet_send(); | |
2651 | } | |
2652 | ||
aa3378df | 2653 | /* |
2654 | * Requests forwarding of X11 connections, generates fake authentication | |
2655 | * data, and enables authentication spoofing. | |
8e7895b8 | 2656 | * This should be called in the client only. |
aa3378df | 2657 | */ |
6ae2364d | 2658 | void |
0b242b12 | 2659 | x11_request_forwarding_with_spoofing(int client_session_id, |
2660 | const char *proto, const char *data) | |
8efc0c15 | 2661 | { |
1e3b8b07 | 2662 | u_int data_len = (u_int) strlen(data) / 2; |
ca910e13 | 2663 | u_int i, value, len; |
5260325f | 2664 | char *new_data; |
2665 | int screen_number; | |
2666 | const char *cp; | |
2667 | u_int32_t rand = 0; | |
2668 | ||
2669 | cp = getenv("DISPLAY"); | |
2670 | if (cp) | |
2671 | cp = strchr(cp, ':'); | |
2672 | if (cp) | |
2673 | cp = strchr(cp, '.'); | |
2674 | if (cp) | |
2675 | screen_number = atoi(cp + 1); | |
2676 | else | |
2677 | screen_number = 0; | |
2678 | ||
2679 | /* Save protocol name. */ | |
2680 | x11_saved_proto = xstrdup(proto); | |
2681 | ||
aa3378df | 2682 | /* |
2683 | * Extract real authentication data and generate fake data of the | |
2684 | * same length. | |
2685 | */ | |
5260325f | 2686 | x11_saved_data = xmalloc(data_len); |
2687 | x11_fake_data = xmalloc(data_len); | |
2688 | for (i = 0; i < data_len; i++) { | |
2689 | if (sscanf(data + 2 * i, "%2x", &value) != 1) | |
2690 | fatal("x11_request_forwarding: bad authentication data: %.100s", data); | |
2691 | if (i % 4 == 0) | |
2692 | rand = arc4random(); | |
2693 | x11_saved_data[i] = value; | |
2694 | x11_fake_data[i] = rand & 0xff; | |
2695 | rand >>= 8; | |
2696 | } | |
2697 | x11_saved_data_len = data_len; | |
2698 | x11_fake_data_len = data_len; | |
2699 | ||
2700 | /* Convert the fake data into hex. */ | |
ca910e13 | 2701 | len = 2 * data_len + 1; |
2702 | new_data = xmalloc(len); | |
5260325f | 2703 | for (i = 0; i < data_len; i++) |
ca910e13 | 2704 | snprintf(new_data + 2 * i, len - 2 * i, |
2705 | "%02x", (u_char) x11_fake_data[i]); | |
5260325f | 2706 | |
2707 | /* Send the request packet. */ | |
0b242b12 | 2708 | if (compat20) { |
2709 | channel_request_start(client_session_id, "x11-req", 0); | |
2710 | packet_put_char(0); /* XXX bool single connection */ | |
2711 | } else { | |
2712 | packet_start(SSH_CMSG_X11_REQUEST_FORWARDING); | |
2713 | } | |
2714 | packet_put_cstring(proto); | |
2715 | packet_put_cstring(new_data); | |
5260325f | 2716 | packet_put_int(screen_number); |
2717 | packet_send(); | |
2718 | packet_write_wait(); | |
2719 | xfree(new_data); | |
8efc0c15 | 2720 | } |
2721 | ||
8e7895b8 | 2722 | |
2723 | /* -- agent forwarding */ | |
2724 | ||
8efc0c15 | 2725 | /* Sends a message to the server to request authentication fd forwarding. */ |
2726 | ||
6ae2364d | 2727 | void |
5260325f | 2728 | auth_request_forwarding() |
8efc0c15 | 2729 | { |
5260325f | 2730 | packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING); |
2731 | packet_send(); | |
2732 | packet_write_wait(); | |
8efc0c15 | 2733 | } |
2734 | ||
aa3378df | 2735 | /* |
2736 | * Returns the name of the forwarded authentication socket. Returns NULL if | |
2737 | * there is no forwarded authentication socket. The returned value points to | |
2738 | * a static buffer. | |
2739 | */ | |
8efc0c15 | 2740 | |
5260325f | 2741 | char * |
2742 | auth_get_socket_name() | |
8efc0c15 | 2743 | { |
8e7895b8 | 2744 | return auth_sock_name; |
8efc0c15 | 2745 | } |
2746 | ||
2747 | /* removes the agent forwarding socket */ | |
2748 | ||
6ae2364d | 2749 | void |
f0f32b8e | 2750 | auth_sock_cleanup_proc(void *_pw) |
5260325f | 2751 | { |
f0f32b8e | 2752 | struct passwd *pw = _pw; |
2753 | ||
e4f7282d | 2754 | if (auth_sock_name) { |
f0f32b8e | 2755 | temporarily_use_uid(pw); |
e4f7282d | 2756 | unlink(auth_sock_name); |
2757 | rmdir(auth_sock_dir); | |
2758 | auth_sock_name = NULL; | |
f0f32b8e | 2759 | restore_uid(); |
e4f7282d | 2760 | } |
8efc0c15 | 2761 | } |
2762 | ||
aa3378df | 2763 | /* |
fa649821 | 2764 | * This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server. |
aa3378df | 2765 | * This starts forwarding authentication requests. |
2766 | */ | |
8efc0c15 | 2767 | |
fa649821 | 2768 | int |
5260325f | 2769 | auth_input_request_forwarding(struct passwd * pw) |
8efc0c15 | 2770 | { |
719fc62f | 2771 | Channel *nc; |
2772 | int sock; | |
5260325f | 2773 | struct sockaddr_un sunaddr; |
2774 | ||
8e7895b8 | 2775 | if (auth_get_socket_name() != NULL) { |
2776 | error("authentication forwarding requested twice."); | |
2777 | return 0; | |
2778 | } | |
5260325f | 2779 | |
2780 | /* Temporarily drop privileged uid for mkdir/bind. */ | |
63bd8c36 | 2781 | temporarily_use_uid(pw); |
5260325f | 2782 | |
2783 | /* Allocate a buffer for the socket name, and format the name. */ | |
8e7895b8 | 2784 | auth_sock_name = xmalloc(MAXPATHLEN); |
2785 | auth_sock_dir = xmalloc(MAXPATHLEN); | |
2786 | strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXX", MAXPATHLEN); | |
5260325f | 2787 | |
2788 | /* Create private directory for socket */ | |
8e7895b8 | 2789 | if (mkdtemp(auth_sock_dir) == NULL) { |
2790 | packet_send_debug("Agent forwarding disabled: " | |
2791 | "mkdtemp() failed: %.100s", strerror(errno)); | |
fa649821 | 2792 | restore_uid(); |
8e7895b8 | 2793 | xfree(auth_sock_name); |
2794 | xfree(auth_sock_dir); | |
2795 | auth_sock_name = NULL; | |
2796 | auth_sock_dir = NULL; | |
fa649821 | 2797 | return 0; |
2798 | } | |
8e7895b8 | 2799 | snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%d", |
2800 | auth_sock_dir, (int) getpid()); | |
5260325f | 2801 | |
e4f7282d | 2802 | /* delete agent socket on fatal() */ |
f0f32b8e | 2803 | fatal_add_cleanup(auth_sock_cleanup_proc, pw); |
e4f7282d | 2804 | |
5260325f | 2805 | /* Create the socket. */ |
2806 | sock = socket(AF_UNIX, SOCK_STREAM, 0); | |
2807 | if (sock < 0) | |
2808 | packet_disconnect("socket: %.100s", strerror(errno)); | |
2809 | ||
2810 | /* Bind it to the name. */ | |
2811 | memset(&sunaddr, 0, sizeof(sunaddr)); | |
2812 | sunaddr.sun_family = AF_UNIX; | |
8e7895b8 | 2813 | strncpy(sunaddr.sun_path, auth_sock_name, |
5260325f | 2814 | sizeof(sunaddr.sun_path)); |
2815 | ||
2816 | if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) | |
2817 | packet_disconnect("bind: %.100s", strerror(errno)); | |
2818 | ||
2819 | /* Restore the privileged uid. */ | |
2820 | restore_uid(); | |
2821 | ||
2822 | /* Start listening on the socket. */ | |
2823 | if (listen(sock, 5) < 0) | |
2824 | packet_disconnect("listen: %.100s", strerror(errno)); | |
2825 | ||
2826 | /* Allocate a channel for the authentication agent socket. */ | |
719fc62f | 2827 | nc = channel_new("auth socket", |
fa08c86b | 2828 | SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1, |
2829 | CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, | |
2830 | 0, xstrdup("auth socket"), 1); | |
719fc62f | 2831 | if (nc == NULL) { |
2832 | error("auth_input_request_forwarding: channel_new failed"); | |
f0f32b8e | 2833 | auth_sock_cleanup_proc(pw); |
750c256a | 2834 | fatal_remove_cleanup(auth_sock_cleanup_proc, pw); |
719fc62f | 2835 | close(sock); |
2836 | return 0; | |
2837 | } | |
8e7895b8 | 2838 | strlcpy(nc->path, auth_sock_name, sizeof(nc->path)); |
fa649821 | 2839 | return 1; |
8efc0c15 | 2840 | } |
2841 | ||
2842 | /* This is called to process an SSH_SMSG_AGENT_OPEN message. */ | |
2843 | ||
6ae2364d | 2844 | void |
188adeb2 | 2845 | auth_input_open_request(int type, int plen, void *ctxt) |
8efc0c15 | 2846 | { |
719fc62f | 2847 | Channel *c = NULL; |
2848 | int remote_id, sock; | |
8e7895b8 | 2849 | char *name; |
5260325f | 2850 | |
7368a6c8 | 2851 | packet_integrity_check(plen, 4, type); |
2852 | ||
5260325f | 2853 | /* Read the remote channel number from the message. */ |
719fc62f | 2854 | remote_id = packet_get_int(); |
5260325f | 2855 | |
aa3378df | 2856 | /* |
2857 | * Get a connection to the local authentication agent (this may again | |
2858 | * get forwarded). | |
2859 | */ | |
5260325f | 2860 | sock = ssh_get_authentication_socket(); |
2861 | ||
aa3378df | 2862 | /* |
2863 | * If we could not connect the agent, send an error message back to | |
2864 | * the server. This should never happen unless the agent dies, | |
2865 | * because authentication forwarding is only enabled if we have an | |
2866 | * agent. | |
2867 | */ | |
719fc62f | 2868 | if (sock >= 0) { |
8e7895b8 | 2869 | name = xstrdup("authentication agent connection"); |
2870 | c = channel_new("", SSH_CHANNEL_OPEN, sock, sock, | |
2871 | -1, 0, 0, 0, name, 1); | |
719fc62f | 2872 | if (c == NULL) { |
2873 | error("auth_input_open_request: channel_new failed"); | |
8e7895b8 | 2874 | xfree(name); |
719fc62f | 2875 | close(sock); |
2876 | } else { | |
2877 | c->remote_id = remote_id; | |
2878 | } | |
2879 | } | |
2880 | if (c == NULL) { | |
5260325f | 2881 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); |
719fc62f | 2882 | packet_put_int(remote_id); |
2883 | } else { | |
2884 | /* Send a confirmation to the remote host. */ | |
2885 | debug("Forwarding authentication connection."); | |
2886 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
2887 | packet_put_int(remote_id); | |
2888 | packet_put_int(c->self); | |
5260325f | 2889 | } |
5260325f | 2890 | packet_send(); |
8efc0c15 | 2891 | } |