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8efc0c15 | 1 | /* |
5260325f | 2 | * Author: Tatu Ylonen <ylo@cs.hut.fi> |
5260325f | 3 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland |
4 | * All rights reserved | |
5260325f | 5 | * This file contains functions for generic socket connection forwarding. |
6 | * There is also code for initiating connection forwarding for X11 connections, | |
7 | * arbitrary tcp/ip connections, and the authentication agent connection. | |
6ae2364d | 8 | * |
bcbf86ec | 9 | * As far as I am concerned, the code I have written for this software |
10 | * can be used freely for any purpose. Any derived versions of this | |
11 | * software must be clearly marked as such, and if the derived work is | |
12 | * incompatible with the protocol description in the RFC file, it must be | |
13 | * called by a name other than "ssh" or "Secure Shell". | |
14 | * | |
7e7327a1 | 15 | * SSH2 support added by Markus Friedl. |
8341f420 | 16 | * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved. |
bcbf86ec | 17 | * Copyright (c) 1999 Dug Song. All rights reserved. |
18 | * Copyright (c) 1999 Theo de Raadt. All rights reserved. | |
19 | * | |
20 | * Redistribution and use in source and binary forms, with or without | |
21 | * modification, are permitted provided that the following conditions | |
22 | * are met: | |
23 | * 1. Redistributions of source code must retain the above copyright | |
24 | * notice, this list of conditions and the following disclaimer. | |
25 | * 2. Redistributions in binary form must reproduce the above copyright | |
26 | * notice, this list of conditions and the following disclaimer in the | |
27 | * documentation and/or other materials provided with the distribution. | |
28 | * | |
29 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR | |
30 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES | |
31 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. | |
32 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, | |
33 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | |
34 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | |
35 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | |
36 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
37 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | |
38 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
5260325f | 39 | */ |
8efc0c15 | 40 | |
41 | #include "includes.h" | |
d7b37427 | 42 | RCSID("$OpenBSD: channels.c,v 1.232 2006/01/30 12:22:22 reyk Exp $"); |
8efc0c15 | 43 | |
44 | #include "ssh.h" | |
42f11eb2 | 45 | #include "ssh1.h" |
46 | #include "ssh2.h" | |
8efc0c15 | 47 | #include "packet.h" |
48 | #include "xmalloc.h" | |
42f11eb2 | 49 | #include "log.h" |
50 | #include "misc.h" | |
8efc0c15 | 51 | #include "channels.h" |
8efc0c15 | 52 | #include "compat.h" |
42f11eb2 | 53 | #include "canohost.h" |
4c8722d9 | 54 | #include "key.h" |
55 | #include "authfd.h" | |
805e659f | 56 | #include "pathnames.h" |
f49658f5 | 57 | #include "bufaux.h" |
8efc0c15 | 58 | |
8e7895b8 | 59 | /* -- channel core */ |
8efc0c15 | 60 | |
aa3378df | 61 | /* |
62 | * Pointer to an array containing all allocated channels. The array is | |
63 | * dynamically extended as needed. | |
64 | */ | |
719fc62f | 65 | static Channel **channels = NULL; |
8efc0c15 | 66 | |
aa3378df | 67 | /* |
68 | * Size of the channel array. All slots of the array must always be | |
719fc62f | 69 | * initialized (at least the type field); unused slots set to NULL |
aa3378df | 70 | */ |
9a995072 | 71 | static u_int channels_alloc = 0; |
8efc0c15 | 72 | |
aa3378df | 73 | /* |
74 | * Maximum file descriptor value used in any of the channels. This is | |
719fc62f | 75 | * updated in channel_new. |
aa3378df | 76 | */ |
39929cdb | 77 | static int channel_max_fd = 0; |
8efc0c15 | 78 | |
8efc0c15 | 79 | |
8e7895b8 | 80 | /* -- tcp forwarding */ |
8efc0c15 | 81 | |
aa3378df | 82 | /* |
83 | * Data structure for storing which hosts are permitted for forward requests. | |
84 | * The local sides of any remote forwards are stored in this array to prevent | |
85 | * a corrupt remote server from accessing arbitrary TCP/IP ports on our local | |
86 | * network (which might be behind a firewall). | |
87 | */ | |
5260325f | 88 | typedef struct { |
7368a6c8 | 89 | char *host_to_connect; /* Connect to 'host'. */ |
90 | u_short port_to_connect; /* Connect to 'port'. */ | |
91 | u_short listen_port; /* Remote side should listen port number. */ | |
8efc0c15 | 92 | } ForwardPermission; |
93 | ||
94 | /* List of all permitted host/port pairs to connect. */ | |
95 | static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION]; | |
8e7895b8 | 96 | |
8efc0c15 | 97 | /* Number of permitted host/port pairs in the array. */ |
98 | static int num_permitted_opens = 0; | |
aa3378df | 99 | /* |
100 | * If this is true, all opens are permitted. This is the case on the server | |
101 | * on which we have to trust the client anyway, and the user could do | |
102 | * anything after logging in anyway. | |
103 | */ | |
8efc0c15 | 104 | static int all_opens_permitted = 0; |
105 | ||
8efc0c15 | 106 | |
8e7895b8 | 107 | /* -- X11 forwarding */ |
42f11eb2 | 108 | |
8e7895b8 | 109 | /* Maximum number of fake X11 displays to try. */ |
110 | #define MAX_DISPLAYS 1000 | |
0490e609 | 111 | |
ef07103c | 112 | /* Saved X11 local (client) display. */ |
113 | static char *x11_saved_display = NULL; | |
114 | ||
8e7895b8 | 115 | /* Saved X11 authentication protocol name. */ |
116 | static char *x11_saved_proto = NULL; | |
8efc0c15 | 117 | |
8e7895b8 | 118 | /* Saved X11 authentication data. This is the real data. */ |
119 | static char *x11_saved_data = NULL; | |
120 | static u_int x11_saved_data_len = 0; | |
121 | ||
122 | /* | |
123 | * Fake X11 authentication data. This is what the server will be sending us; | |
124 | * we should replace any occurrences of this by the real data. | |
125 | */ | |
126 | static char *x11_fake_data = NULL; | |
127 | static u_int x11_fake_data_len; | |
128 | ||
129 | ||
130 | /* -- agent forwarding */ | |
8efc0c15 | 131 | |
8e7895b8 | 132 | #define NUM_SOCKS 10 |
133 | ||
8e7895b8 | 134 | /* AF_UNSPEC or AF_INET or AF_INET6 */ |
5e4a7219 | 135 | static int IPv4or6 = AF_UNSPEC; |
8e7895b8 | 136 | |
137 | /* helper */ | |
396c147e | 138 | static void port_open_helper(Channel *c, char *rtype); |
8e7895b8 | 139 | |
140 | /* -- channel core */ | |
7368a6c8 | 141 | |
142 | Channel * | |
b872f7f0 | 143 | channel_by_id(int id) |
7368a6c8 | 144 | { |
145 | Channel *c; | |
719fc62f | 146 | |
9a995072 | 147 | if (id < 0 || (u_int)id >= channels_alloc) { |
b872f7f0 | 148 | logit("channel_by_id: %d: bad id", id); |
7368a6c8 | 149 | return NULL; |
150 | } | |
719fc62f | 151 | c = channels[id]; |
152 | if (c == NULL) { | |
b872f7f0 | 153 | logit("channel_by_id: %d: bad id: channel free", id); |
7368a6c8 | 154 | return NULL; |
155 | } | |
156 | return c; | |
157 | } | |
158 | ||
b872f7f0 | 159 | /* |
160 | * Returns the channel if it is allowed to receive protocol messages. | |
161 | * Private channels, like listening sockets, may not receive messages. | |
162 | */ | |
163 | Channel * | |
164 | channel_lookup(int id) | |
165 | { | |
166 | Channel *c; | |
167 | ||
168 | if ((c = channel_by_id(id)) == NULL) | |
169 | return (NULL); | |
170 | ||
171 | switch(c->type) { | |
172 | case SSH_CHANNEL_X11_OPEN: | |
173 | case SSH_CHANNEL_LARVAL: | |
174 | case SSH_CHANNEL_CONNECTING: | |
175 | case SSH_CHANNEL_DYNAMIC: | |
176 | case SSH_CHANNEL_OPENING: | |
177 | case SSH_CHANNEL_OPEN: | |
178 | case SSH_CHANNEL_INPUT_DRAINING: | |
179 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
180 | return (c); | |
181 | break; | |
182 | } | |
183 | logit("Non-public channel %d, type %d.", id, c->type); | |
184 | return (NULL); | |
185 | } | |
186 | ||
aa3378df | 187 | /* |
1d1ffb87 | 188 | * Register filedescriptors for a channel, used when allocating a channel or |
0fbe8c74 | 189 | * when the channel consumer/producer is ready, e.g. shell exec'd |
aa3378df | 190 | */ |
8efc0c15 | 191 | |
396c147e | 192 | static void |
a22aff1f | 193 | channel_register_fds(Channel *c, int rfd, int wfd, int efd, |
194 | int extusage, int nonblock) | |
8efc0c15 | 195 | { |
5260325f | 196 | /* Update the maximum file descriptor value. */ |
39929cdb | 197 | channel_max_fd = MAX(channel_max_fd, rfd); |
198 | channel_max_fd = MAX(channel_max_fd, wfd); | |
199 | channel_max_fd = MAX(channel_max_fd, efd); | |
200 | ||
aa3378df | 201 | /* XXX set close-on-exec -markus */ |
1d1ffb87 | 202 | |
0fbe8c74 | 203 | c->rfd = rfd; |
204 | c->wfd = wfd; | |
205 | c->sock = (rfd == wfd) ? rfd : -1; | |
5e96b616 | 206 | c->ctl_fd = -1; /* XXX: set elsewhere */ |
0fbe8c74 | 207 | c->efd = efd; |
208 | c->extended_usage = extusage; | |
a22aff1f | 209 | |
0ae4fe1d | 210 | /* XXX ugly hack: nonblock is only set by the server */ |
211 | if (nonblock && isatty(c->rfd)) { | |
d7ac5f18 | 212 | debug2("channel %d: rfd %d isatty", c->self, c->rfd); |
0ae4fe1d | 213 | c->isatty = 1; |
214 | if (!isatty(c->wfd)) { | |
94dfb550 | 215 | error("channel %d: wfd %d is not a tty?", |
0ae4fe1d | 216 | c->self, c->wfd); |
217 | } | |
218 | } else { | |
219 | c->isatty = 0; | |
220 | } | |
21c2c5cd | 221 | c->wfd_isatty = isatty(c->wfd); |
0ae4fe1d | 222 | |
a22aff1f | 223 | /* enable nonblocking mode */ |
224 | if (nonblock) { | |
225 | if (rfd != -1) | |
226 | set_nonblock(rfd); | |
227 | if (wfd != -1) | |
228 | set_nonblock(wfd); | |
229 | if (efd != -1) | |
230 | set_nonblock(efd); | |
231 | } | |
0fbe8c74 | 232 | } |
233 | ||
234 | /* | |
235 | * Allocate a new channel object and set its type and socket. This will cause | |
236 | * remote_name to be freed. | |
237 | */ | |
238 | ||
719fc62f | 239 | Channel * |
0fbe8c74 | 240 | channel_new(char *ctype, int type, int rfd, int wfd, int efd, |
f91d9a89 | 241 | u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock) |
0fbe8c74 | 242 | { |
9a995072 | 243 | int found; |
244 | u_int i; | |
0fbe8c74 | 245 | Channel *c; |
5260325f | 246 | |
247 | /* Do initial allocation if this is the first call. */ | |
248 | if (channels_alloc == 0) { | |
249 | channels_alloc = 10; | |
719fc62f | 250 | channels = xmalloc(channels_alloc * sizeof(Channel *)); |
5260325f | 251 | for (i = 0; i < channels_alloc; i++) |
719fc62f | 252 | channels[i] = NULL; |
5260325f | 253 | } |
254 | /* Try to find a free slot where to put the new channel. */ | |
255 | for (found = -1, i = 0; i < channels_alloc; i++) | |
719fc62f | 256 | if (channels[i] == NULL) { |
5260325f | 257 | /* Found a free slot. */ |
9a995072 | 258 | found = (int)i; |
5260325f | 259 | break; |
260 | } | |
9a995072 | 261 | if (found < 0) { |
aa3378df | 262 | /* There are no free slots. Take last+1 slot and expand the array. */ |
5260325f | 263 | found = channels_alloc; |
5df8c731 | 264 | if (channels_alloc > 10000) |
265 | fatal("channel_new: internal error: channels_alloc %d " | |
266 | "too big.", channels_alloc); | |
20419cc1 | 267 | channels = xrealloc(channels, |
268 | (channels_alloc + 10) * sizeof(Channel *)); | |
269 | channels_alloc += 10; | |
de273eef | 270 | debug2("channel: expanding %d", channels_alloc); |
5260325f | 271 | for (i = found; i < channels_alloc; i++) |
719fc62f | 272 | channels[i] = NULL; |
5260325f | 273 | } |
719fc62f | 274 | /* Initialize and return new channel. */ |
275 | c = channels[found] = xmalloc(sizeof(Channel)); | |
639cb8ab | 276 | memset(c, 0, sizeof(Channel)); |
5260325f | 277 | buffer_init(&c->input); |
278 | buffer_init(&c->output); | |
7368a6c8 | 279 | buffer_init(&c->extended); |
70bef40e | 280 | c->ostate = CHAN_OUTPUT_OPEN; |
281 | c->istate = CHAN_INPUT_OPEN; | |
282 | c->flags = 0; | |
a22aff1f | 283 | channel_register_fds(c, rfd, wfd, efd, extusage, nonblock); |
5260325f | 284 | c->self = found; |
285 | c->type = type; | |
7368a6c8 | 286 | c->ctype = ctype; |
0b242b12 | 287 | c->local_window = window; |
288 | c->local_window_max = window; | |
289 | c->local_consumed = 0; | |
290 | c->local_maxpacket = maxpack; | |
5260325f | 291 | c->remote_id = -1; |
0d942eff | 292 | c->remote_name = xstrdup(remote_name); |
7368a6c8 | 293 | c->remote_window = 0; |
294 | c->remote_maxpacket = 0; | |
a5f82435 | 295 | c->force_drain = 0; |
ac151b18 | 296 | c->single_connection = 0; |
3cf2be58 | 297 | c->detach_user = NULL; |
8cd0437d | 298 | c->detach_close = 0; |
05ca0898 | 299 | c->confirm = NULL; |
5e96b616 | 300 | c->confirm_ctx = NULL; |
2e73a022 | 301 | c->input_filter = NULL; |
c1c6a032 | 302 | c->output_filter = NULL; |
5260325f | 303 | debug("channel %d: new [%s]", found, remote_name); |
719fc62f | 304 | return c; |
7368a6c8 | 305 | } |
8efc0c15 | 306 | |
489aa2e9 | 307 | static int |
308 | channel_find_maxfd(void) | |
309 | { | |
9a995072 | 310 | u_int i; |
311 | int max = 0; | |
489aa2e9 | 312 | Channel *c; |
313 | ||
314 | for (i = 0; i < channels_alloc; i++) { | |
315 | c = channels[i]; | |
316 | if (c != NULL) { | |
317 | max = MAX(max, c->rfd); | |
318 | max = MAX(max, c->wfd); | |
319 | max = MAX(max, c->efd); | |
320 | } | |
321 | } | |
322 | return max; | |
323 | } | |
324 | ||
325 | int | |
326 | channel_close_fd(int *fdp) | |
327 | { | |
328 | int ret = 0, fd = *fdp; | |
329 | ||
330 | if (fd != -1) { | |
331 | ret = close(fd); | |
332 | *fdp = -1; | |
333 | if (fd == channel_max_fd) | |
334 | channel_max_fd = channel_find_maxfd(); | |
335 | } | |
336 | return ret; | |
337 | } | |
338 | ||
0fbe8c74 | 339 | /* Close all channel fd/socket. */ |
340 | ||
396c147e | 341 | static void |
0fbe8c74 | 342 | channel_close_fds(Channel *c) |
343 | { | |
5e96b616 | 344 | debug3("channel %d: close_fds r %d w %d e %d c %d", |
345 | c->self, c->rfd, c->wfd, c->efd, c->ctl_fd); | |
6fd8622b | 346 | |
489aa2e9 | 347 | channel_close_fd(&c->sock); |
5e96b616 | 348 | channel_close_fd(&c->ctl_fd); |
489aa2e9 | 349 | channel_close_fd(&c->rfd); |
350 | channel_close_fd(&c->wfd); | |
351 | channel_close_fd(&c->efd); | |
0fbe8c74 | 352 | } |
353 | ||
8e7895b8 | 354 | /* Free the channel and close its fd/socket. */ |
355 | ||
356 | void | |
357 | channel_free(Channel *c) | |
358 | { | |
359 | char *s; | |
9a995072 | 360 | u_int i, n; |
8e7895b8 | 361 | |
362 | for (n = 0, i = 0; i < channels_alloc; i++) | |
363 | if (channels[i]) | |
364 | n++; | |
9a995072 | 365 | debug("channel %d: free: %s, nchannels %u", c->self, |
8e7895b8 | 366 | c->remote_name ? c->remote_name : "???", n); |
367 | ||
368 | s = channel_open_message(); | |
d7ac5f18 | 369 | debug3("channel %d: status: %s", c->self, s); |
8e7895b8 | 370 | xfree(s); |
371 | ||
8e7895b8 | 372 | if (c->sock != -1) |
373 | shutdown(c->sock, SHUT_RDWR); | |
5e96b616 | 374 | if (c->ctl_fd != -1) |
375 | shutdown(c->ctl_fd, SHUT_RDWR); | |
8e7895b8 | 376 | channel_close_fds(c); |
377 | buffer_free(&c->input); | |
378 | buffer_free(&c->output); | |
379 | buffer_free(&c->extended); | |
380 | if (c->remote_name) { | |
381 | xfree(c->remote_name); | |
382 | c->remote_name = NULL; | |
383 | } | |
384 | channels[c->self] = NULL; | |
385 | xfree(c); | |
386 | } | |
387 | ||
8e7895b8 | 388 | void |
d6746a0b | 389 | channel_free_all(void) |
8e7895b8 | 390 | { |
9a995072 | 391 | u_int i; |
8e7895b8 | 392 | |
d6746a0b | 393 | for (i = 0; i < channels_alloc; i++) |
394 | if (channels[i] != NULL) | |
395 | channel_free(channels[i]); | |
8e7895b8 | 396 | } |
397 | ||
398 | /* | |
399 | * Closes the sockets/fds of all channels. This is used to close extra file | |
400 | * descriptors after a fork. | |
401 | */ | |
402 | ||
403 | void | |
d5bb9418 | 404 | channel_close_all(void) |
8e7895b8 | 405 | { |
9a995072 | 406 | u_int i; |
8e7895b8 | 407 | |
408 | for (i = 0; i < channels_alloc; i++) | |
409 | if (channels[i] != NULL) | |
410 | channel_close_fds(channels[i]); | |
411 | } | |
412 | ||
3cf2be58 | 413 | /* |
414 | * Stop listening to channels. | |
415 | */ | |
416 | ||
417 | void | |
418 | channel_stop_listening(void) | |
419 | { | |
9a995072 | 420 | u_int i; |
3cf2be58 | 421 | Channel *c; |
422 | ||
423 | for (i = 0; i < channels_alloc; i++) { | |
424 | c = channels[i]; | |
425 | if (c != NULL) { | |
426 | switch (c->type) { | |
427 | case SSH_CHANNEL_AUTH_SOCKET: | |
428 | case SSH_CHANNEL_PORT_LISTENER: | |
429 | case SSH_CHANNEL_RPORT_LISTENER: | |
430 | case SSH_CHANNEL_X11_LISTENER: | |
489aa2e9 | 431 | channel_close_fd(&c->sock); |
3cf2be58 | 432 | channel_free(c); |
433 | break; | |
434 | } | |
435 | } | |
436 | } | |
437 | } | |
438 | ||
8e7895b8 | 439 | /* |
440 | * Returns true if no channel has too much buffered data, and false if one or | |
441 | * more channel is overfull. | |
442 | */ | |
443 | ||
444 | int | |
d5bb9418 | 445 | channel_not_very_much_buffered_data(void) |
8e7895b8 | 446 | { |
447 | u_int i; | |
448 | Channel *c; | |
449 | ||
450 | for (i = 0; i < channels_alloc; i++) { | |
451 | c = channels[i]; | |
452 | if (c != NULL && c->type == SSH_CHANNEL_OPEN) { | |
0c139bd1 | 453 | #if 0 |
454 | if (!compat20 && | |
455 | buffer_len(&c->input) > packet_get_maxsize()) { | |
faa483fa | 456 | debug2("channel %d: big input buffer %d", |
8e7895b8 | 457 | c->self, buffer_len(&c->input)); |
458 | return 0; | |
459 | } | |
0c139bd1 | 460 | #endif |
8e7895b8 | 461 | if (buffer_len(&c->output) > packet_get_maxsize()) { |
a27002e5 | 462 | debug2("channel %d: big output buffer %u > %u", |
0c139bd1 | 463 | c->self, buffer_len(&c->output), |
464 | packet_get_maxsize()); | |
8e7895b8 | 465 | return 0; |
466 | } | |
467 | } | |
468 | } | |
469 | return 1; | |
470 | } | |
471 | ||
472 | /* Returns true if any channel is still open. */ | |
473 | ||
474 | int | |
d5bb9418 | 475 | channel_still_open(void) |
8e7895b8 | 476 | { |
9a995072 | 477 | u_int i; |
8e7895b8 | 478 | Channel *c; |
479 | ||
480 | for (i = 0; i < channels_alloc; i++) { | |
481 | c = channels[i]; | |
482 | if (c == NULL) | |
483 | continue; | |
484 | switch (c->type) { | |
485 | case SSH_CHANNEL_X11_LISTENER: | |
486 | case SSH_CHANNEL_PORT_LISTENER: | |
487 | case SSH_CHANNEL_RPORT_LISTENER: | |
488 | case SSH_CHANNEL_CLOSED: | |
489 | case SSH_CHANNEL_AUTH_SOCKET: | |
490 | case SSH_CHANNEL_DYNAMIC: | |
491 | case SSH_CHANNEL_CONNECTING: | |
492 | case SSH_CHANNEL_ZOMBIE: | |
493 | continue; | |
494 | case SSH_CHANNEL_LARVAL: | |
495 | if (!compat20) | |
496 | fatal("cannot happen: SSH_CHANNEL_LARVAL"); | |
497 | continue; | |
498 | case SSH_CHANNEL_OPENING: | |
499 | case SSH_CHANNEL_OPEN: | |
500 | case SSH_CHANNEL_X11_OPEN: | |
501 | return 1; | |
502 | case SSH_CHANNEL_INPUT_DRAINING: | |
503 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
504 | if (!compat13) | |
505 | fatal("cannot happen: OUT_DRAIN"); | |
506 | return 1; | |
507 | default: | |
508 | fatal("channel_still_open: bad channel type %d", c->type); | |
509 | /* NOTREACHED */ | |
510 | } | |
511 | } | |
512 | return 0; | |
513 | } | |
514 | ||
515 | /* Returns the id of an open channel suitable for keepaliving */ | |
516 | ||
517 | int | |
d5bb9418 | 518 | channel_find_open(void) |
8e7895b8 | 519 | { |
9a995072 | 520 | u_int i; |
8e7895b8 | 521 | Channel *c; |
522 | ||
523 | for (i = 0; i < channels_alloc; i++) { | |
524 | c = channels[i]; | |
13de3560 | 525 | if (c == NULL || c->remote_id < 0) |
8e7895b8 | 526 | continue; |
527 | switch (c->type) { | |
528 | case SSH_CHANNEL_CLOSED: | |
529 | case SSH_CHANNEL_DYNAMIC: | |
530 | case SSH_CHANNEL_X11_LISTENER: | |
531 | case SSH_CHANNEL_PORT_LISTENER: | |
532 | case SSH_CHANNEL_RPORT_LISTENER: | |
533 | case SSH_CHANNEL_OPENING: | |
534 | case SSH_CHANNEL_CONNECTING: | |
535 | case SSH_CHANNEL_ZOMBIE: | |
536 | continue; | |
537 | case SSH_CHANNEL_LARVAL: | |
538 | case SSH_CHANNEL_AUTH_SOCKET: | |
539 | case SSH_CHANNEL_OPEN: | |
540 | case SSH_CHANNEL_X11_OPEN: | |
541 | return i; | |
542 | case SSH_CHANNEL_INPUT_DRAINING: | |
543 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
544 | if (!compat13) | |
545 | fatal("cannot happen: OUT_DRAIN"); | |
546 | return i; | |
547 | default: | |
548 | fatal("channel_find_open: bad channel type %d", c->type); | |
549 | /* NOTREACHED */ | |
550 | } | |
551 | } | |
552 | return -1; | |
553 | } | |
554 | ||
555 | ||
556 | /* | |
557 | * Returns a message describing the currently open forwarded connections, | |
558 | * suitable for sending to the client. The message contains crlf pairs for | |
559 | * newlines. | |
560 | */ | |
561 | ||
562 | char * | |
d5bb9418 | 563 | channel_open_message(void) |
8e7895b8 | 564 | { |
565 | Buffer buffer; | |
566 | Channel *c; | |
567 | char buf[1024], *cp; | |
9a995072 | 568 | u_int i; |
8e7895b8 | 569 | |
570 | buffer_init(&buffer); | |
571 | snprintf(buf, sizeof buf, "The following connections are open:\r\n"); | |
572 | buffer_append(&buffer, buf, strlen(buf)); | |
573 | for (i = 0; i < channels_alloc; i++) { | |
574 | c = channels[i]; | |
575 | if (c == NULL) | |
576 | continue; | |
577 | switch (c->type) { | |
578 | case SSH_CHANNEL_X11_LISTENER: | |
579 | case SSH_CHANNEL_PORT_LISTENER: | |
580 | case SSH_CHANNEL_RPORT_LISTENER: | |
581 | case SSH_CHANNEL_CLOSED: | |
582 | case SSH_CHANNEL_AUTH_SOCKET: | |
583 | case SSH_CHANNEL_ZOMBIE: | |
584 | continue; | |
585 | case SSH_CHANNEL_LARVAL: | |
586 | case SSH_CHANNEL_OPENING: | |
587 | case SSH_CHANNEL_CONNECTING: | |
588 | case SSH_CHANNEL_DYNAMIC: | |
589 | case SSH_CHANNEL_OPEN: | |
590 | case SSH_CHANNEL_X11_OPEN: | |
591 | case SSH_CHANNEL_INPUT_DRAINING: | |
592 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
5e96b616 | 593 | snprintf(buf, sizeof buf, |
594 | " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d cfd %d)\r\n", | |
8e7895b8 | 595 | c->self, c->remote_name, |
596 | c->type, c->remote_id, | |
597 | c->istate, buffer_len(&c->input), | |
598 | c->ostate, buffer_len(&c->output), | |
5e96b616 | 599 | c->rfd, c->wfd, c->ctl_fd); |
8e7895b8 | 600 | buffer_append(&buffer, buf, strlen(buf)); |
601 | continue; | |
602 | default: | |
603 | fatal("channel_open_message: bad channel type %d", c->type); | |
604 | /* NOTREACHED */ | |
605 | } | |
606 | } | |
607 | buffer_append(&buffer, "\0", 1); | |
608 | cp = xstrdup(buffer_ptr(&buffer)); | |
609 | buffer_free(&buffer); | |
610 | return cp; | |
611 | } | |
612 | ||
613 | void | |
614 | channel_send_open(int id) | |
615 | { | |
616 | Channel *c = channel_lookup(id); | |
e1feb9bf | 617 | |
8e7895b8 | 618 | if (c == NULL) { |
bbe88b6d | 619 | logit("channel_send_open: %d: bad id", id); |
8e7895b8 | 620 | return; |
621 | } | |
6226a8f8 | 622 | debug2("channel %d: send open", id); |
8e7895b8 | 623 | packet_start(SSH2_MSG_CHANNEL_OPEN); |
624 | packet_put_cstring(c->ctype); | |
625 | packet_put_int(c->self); | |
626 | packet_put_int(c->local_window); | |
627 | packet_put_int(c->local_maxpacket); | |
628 | packet_send(); | |
629 | } | |
630 | ||
631 | void | |
6226a8f8 | 632 | channel_request_start(int id, char *service, int wantconfirm) |
8e7895b8 | 633 | { |
6226a8f8 | 634 | Channel *c = channel_lookup(id); |
e1feb9bf | 635 | |
8e7895b8 | 636 | if (c == NULL) { |
bbe88b6d | 637 | logit("channel_request_start: %d: unknown channel id", id); |
8e7895b8 | 638 | return; |
639 | } | |
5e96b616 | 640 | debug2("channel %d: request %s confirm %d", id, service, wantconfirm); |
8e7895b8 | 641 | packet_start(SSH2_MSG_CHANNEL_REQUEST); |
642 | packet_put_int(c->remote_id); | |
643 | packet_put_cstring(service); | |
644 | packet_put_char(wantconfirm); | |
645 | } | |
646 | void | |
5e96b616 | 647 | channel_register_confirm(int id, channel_callback_fn *fn, void *ctx) |
8e7895b8 | 648 | { |
649 | Channel *c = channel_lookup(id); | |
e1feb9bf | 650 | |
8e7895b8 | 651 | if (c == NULL) { |
bbe88b6d | 652 | logit("channel_register_comfirm: %d: bad id", id); |
8e7895b8 | 653 | return; |
654 | } | |
05ca0898 | 655 | c->confirm = fn; |
5e96b616 | 656 | c->confirm_ctx = ctx; |
8e7895b8 | 657 | } |
658 | void | |
8cd0437d | 659 | channel_register_cleanup(int id, channel_callback_fn *fn, int do_close) |
8e7895b8 | 660 | { |
b872f7f0 | 661 | Channel *c = channel_by_id(id); |
e1feb9bf | 662 | |
8e7895b8 | 663 | if (c == NULL) { |
bbe88b6d | 664 | logit("channel_register_cleanup: %d: bad id", id); |
8e7895b8 | 665 | return; |
666 | } | |
3cf2be58 | 667 | c->detach_user = fn; |
8cd0437d | 668 | c->detach_close = do_close; |
8e7895b8 | 669 | } |
670 | void | |
671 | channel_cancel_cleanup(int id) | |
672 | { | |
b872f7f0 | 673 | Channel *c = channel_by_id(id); |
e1feb9bf | 674 | |
8e7895b8 | 675 | if (c == NULL) { |
bbe88b6d | 676 | logit("channel_cancel_cleanup: %d: bad id", id); |
8e7895b8 | 677 | return; |
678 | } | |
3cf2be58 | 679 | c->detach_user = NULL; |
8cd0437d | 680 | c->detach_close = 0; |
8e7895b8 | 681 | } |
682 | void | |
c1c6a032 | 683 | channel_register_filter(int id, channel_infilter_fn *ifn, |
684 | channel_outfilter_fn *ofn) | |
8e7895b8 | 685 | { |
686 | Channel *c = channel_lookup(id); | |
e1feb9bf | 687 | |
8e7895b8 | 688 | if (c == NULL) { |
bbe88b6d | 689 | logit("channel_register_filter: %d: bad id", id); |
8e7895b8 | 690 | return; |
691 | } | |
c1c6a032 | 692 | c->input_filter = ifn; |
693 | c->output_filter = ofn; | |
8e7895b8 | 694 | } |
695 | ||
6ae2364d | 696 | void |
8e7895b8 | 697 | channel_set_fds(int id, int rfd, int wfd, int efd, |
399d1ea6 | 698 | int extusage, int nonblock, u_int window_max) |
8efc0c15 | 699 | { |
8e7895b8 | 700 | Channel *c = channel_lookup(id); |
e1feb9bf | 701 | |
8e7895b8 | 702 | if (c == NULL || c->type != SSH_CHANNEL_LARVAL) |
703 | fatal("channel_activate for non-larval channel %d.", id); | |
704 | channel_register_fds(c, rfd, wfd, efd, extusage, nonblock); | |
705 | c->type = SSH_CHANNEL_OPEN; | |
399d1ea6 | 706 | c->local_window = c->local_window_max = window_max; |
8e7895b8 | 707 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); |
708 | packet_put_int(c->remote_id); | |
709 | packet_put_int(c->local_window); | |
710 | packet_send(); | |
8efc0c15 | 711 | } |
712 | ||
aa3378df | 713 | /* |
7368a6c8 | 714 | * 'channel_pre*' are called just before select() to add any bits relevant to |
715 | * channels in the select bitmasks. | |
aa3378df | 716 | */ |
7368a6c8 | 717 | /* |
718 | * 'channel_post*': perform any appropriate operations for channels which | |
719 | * have events pending. | |
720 | */ | |
721 | typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset); | |
722 | chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE]; | |
723 | chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE]; | |
8efc0c15 | 724 | |
396c147e | 725 | static void |
7368a6c8 | 726 | channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset) |
8efc0c15 | 727 | { |
7368a6c8 | 728 | FD_SET(c->sock, readset); |
729 | } | |
5260325f | 730 | |
396c147e | 731 | static void |
97fb6912 | 732 | channel_pre_connecting(Channel *c, fd_set * readset, fd_set * writeset) |
733 | { | |
734 | debug3("channel %d: waiting for connection", c->self); | |
735 | FD_SET(c->sock, writeset); | |
736 | } | |
737 | ||
396c147e | 738 | static void |
7368a6c8 | 739 | channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset) |
740 | { | |
741 | if (buffer_len(&c->input) < packet_get_maxsize()) | |
742 | FD_SET(c->sock, readset); | |
743 | if (buffer_len(&c->output) > 0) | |
744 | FD_SET(c->sock, writeset); | |
745 | } | |
5260325f | 746 | |
396c147e | 747 | static void |
0c0738d5 | 748 | channel_pre_open(Channel *c, fd_set * readset, fd_set * writeset) |
7368a6c8 | 749 | { |
0c0738d5 | 750 | u_int limit = compat20 ? c->remote_window : packet_get_maxsize(); |
5260325f | 751 | |
fa1d7d85 | 752 | /* check buffer limits */ |
753 | limit = MIN(limit, (BUFFER_MAX_LEN - BUFFER_MAX_CHUNK - CHAN_RBUF)); | |
754 | ||
7e7327a1 | 755 | if (c->istate == CHAN_INPUT_OPEN && |
0c0738d5 | 756 | limit > 0 && |
757 | buffer_len(&c->input) < limit) | |
7e7327a1 | 758 | FD_SET(c->rfd, readset); |
759 | if (c->ostate == CHAN_OUTPUT_OPEN || | |
760 | c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
761 | if (buffer_len(&c->output) > 0) { | |
762 | FD_SET(c->wfd, writeset); | |
763 | } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
d2296ed7 | 764 | if (CHANNEL_EFD_OUTPUT_ACTIVE(c)) |
4e2e5cfd | 765 | debug2("channel %d: obuf_empty delayed efd %d/(%d)", |
766 | c->self, c->efd, buffer_len(&c->extended)); | |
d2296ed7 | 767 | else |
768 | chan_obuf_empty(c); | |
7e7327a1 | 769 | } |
770 | } | |
771 | /** XXX check close conditions, too */ | |
0c0738d5 | 772 | if (compat20 && c->efd != -1) { |
7e7327a1 | 773 | if (c->extended_usage == CHAN_EXTENDED_WRITE && |
774 | buffer_len(&c->extended) > 0) | |
775 | FD_SET(c->efd, writeset); | |
d2296ed7 | 776 | else if (!(c->flags & CHAN_EOF_SENT) && |
777 | c->extended_usage == CHAN_EXTENDED_READ && | |
7e7327a1 | 778 | buffer_len(&c->extended) < c->remote_window) |
779 | FD_SET(c->efd, readset); | |
780 | } | |
5e96b616 | 781 | /* XXX: What about efd? races? */ |
f2107e97 | 782 | if (compat20 && c->ctl_fd != -1 && |
5e96b616 | 783 | c->istate == CHAN_INPUT_OPEN && c->ostate == CHAN_OUTPUT_OPEN) |
784 | FD_SET(c->ctl_fd, readset); | |
7e7327a1 | 785 | } |
786 | ||
396c147e | 787 | static void |
7368a6c8 | 788 | channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset) |
789 | { | |
790 | if (buffer_len(&c->input) == 0) { | |
791 | packet_start(SSH_MSG_CHANNEL_CLOSE); | |
792 | packet_put_int(c->remote_id); | |
793 | packet_send(); | |
794 | c->type = SSH_CHANNEL_CLOSED; | |
d7ac5f18 | 795 | debug2("channel %d: closing after input drain.", c->self); |
7368a6c8 | 796 | } |
797 | } | |
5260325f | 798 | |
396c147e | 799 | static void |
7368a6c8 | 800 | channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset) |
801 | { | |
802 | if (buffer_len(&c->output) == 0) | |
719fc62f | 803 | chan_mark_dead(c); |
6ae2364d | 804 | else |
7368a6c8 | 805 | FD_SET(c->sock, writeset); |
806 | } | |
5260325f | 807 | |
7368a6c8 | 808 | /* |
809 | * This is a special state for X11 authentication spoofing. An opened X11 | |
810 | * connection (when authentication spoofing is being done) remains in this | |
811 | * state until the first packet has been completely read. The authentication | |
812 | * data in that packet is then substituted by the real data if it matches the | |
813 | * fake data, and the channel is put into normal mode. | |
0b242b12 | 814 | * XXX All this happens at the client side. |
8e7895b8 | 815 | * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok |
7368a6c8 | 816 | */ |
396c147e | 817 | static int |
8e7895b8 | 818 | x11_open_helper(Buffer *b) |
7368a6c8 | 819 | { |
1e3b8b07 | 820 | u_char *ucp; |
821 | u_int proto_len, data_len; | |
5260325f | 822 | |
7368a6c8 | 823 | /* Check if the fixed size part of the packet is in buffer. */ |
8e7895b8 | 824 | if (buffer_len(b) < 12) |
7368a6c8 | 825 | return 0; |
826 | ||
827 | /* Parse the lengths of variable-length fields. */ | |
20905a8e | 828 | ucp = buffer_ptr(b); |
7368a6c8 | 829 | if (ucp[0] == 0x42) { /* Byte order MSB first. */ |
830 | proto_len = 256 * ucp[6] + ucp[7]; | |
831 | data_len = 256 * ucp[8] + ucp[9]; | |
832 | } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */ | |
833 | proto_len = ucp[6] + 256 * ucp[7]; | |
834 | data_len = ucp[8] + 256 * ucp[9]; | |
835 | } else { | |
d7ac5f18 | 836 | debug2("Initial X11 packet contains bad byte order byte: 0x%x", |
184eed6a | 837 | ucp[0]); |
7368a6c8 | 838 | return -1; |
839 | } | |
5260325f | 840 | |
7368a6c8 | 841 | /* Check if the whole packet is in buffer. */ |
8e7895b8 | 842 | if (buffer_len(b) < |
7368a6c8 | 843 | 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3)) |
844 | return 0; | |
5260325f | 845 | |
7368a6c8 | 846 | /* Check if authentication protocol matches. */ |
847 | if (proto_len != strlen(x11_saved_proto) || | |
848 | memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) { | |
d7ac5f18 | 849 | debug2("X11 connection uses different authentication protocol."); |
7368a6c8 | 850 | return -1; |
851 | } | |
852 | /* Check if authentication data matches our fake data. */ | |
853 | if (data_len != x11_fake_data_len || | |
854 | memcmp(ucp + 12 + ((proto_len + 3) & ~3), | |
855 | x11_fake_data, x11_fake_data_len) != 0) { | |
d7ac5f18 | 856 | debug2("X11 auth data does not match fake data."); |
7368a6c8 | 857 | return -1; |
858 | } | |
859 | /* Check fake data length */ | |
860 | if (x11_fake_data_len != x11_saved_data_len) { | |
861 | error("X11 fake_data_len %d != saved_data_len %d", | |
862 | x11_fake_data_len, x11_saved_data_len); | |
863 | return -1; | |
864 | } | |
865 | /* | |
866 | * Received authentication protocol and data match | |
867 | * our fake data. Substitute the fake data with real | |
868 | * data. | |
869 | */ | |
870 | memcpy(ucp + 12 + ((proto_len + 3) & ~3), | |
871 | x11_saved_data, x11_saved_data_len); | |
872 | return 1; | |
873 | } | |
5260325f | 874 | |
396c147e | 875 | static void |
7368a6c8 | 876 | channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset) |
877 | { | |
8e7895b8 | 878 | int ret = x11_open_helper(&c->output); |
e1feb9bf | 879 | |
7368a6c8 | 880 | if (ret == 1) { |
881 | /* Start normal processing for the channel. */ | |
882 | c->type = SSH_CHANNEL_OPEN; | |
a8be9f80 | 883 | channel_pre_open_13(c, readset, writeset); |
7368a6c8 | 884 | } else if (ret == -1) { |
885 | /* | |
886 | * We have received an X11 connection that has bad | |
887 | * authentication information. | |
888 | */ | |
bbe88b6d | 889 | logit("X11 connection rejected because of wrong authentication."); |
7368a6c8 | 890 | buffer_clear(&c->input); |
891 | buffer_clear(&c->output); | |
489aa2e9 | 892 | channel_close_fd(&c->sock); |
7368a6c8 | 893 | c->sock = -1; |
894 | c->type = SSH_CHANNEL_CLOSED; | |
895 | packet_start(SSH_MSG_CHANNEL_CLOSE); | |
896 | packet_put_int(c->remote_id); | |
897 | packet_send(); | |
898 | } | |
899 | } | |
5260325f | 900 | |
396c147e | 901 | static void |
0b242b12 | 902 | channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset) |
7368a6c8 | 903 | { |
8e7895b8 | 904 | int ret = x11_open_helper(&c->output); |
a5f82435 | 905 | |
906 | /* c->force_drain = 1; */ | |
907 | ||
7368a6c8 | 908 | if (ret == 1) { |
909 | c->type = SSH_CHANNEL_OPEN; | |
0c0738d5 | 910 | channel_pre_open(c, readset, writeset); |
7368a6c8 | 911 | } else if (ret == -1) { |
bbe88b6d | 912 | logit("X11 connection rejected because of wrong authentication."); |
d7ac5f18 | 913 | debug2("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate); |
8341f420 | 914 | chan_read_failed(c); |
915 | buffer_clear(&c->input); | |
916 | chan_ibuf_empty(c); | |
917 | buffer_clear(&c->output); | |
918 | /* for proto v1, the peer will send an IEOF */ | |
919 | if (compat20) | |
920 | chan_write_failed(c); | |
921 | else | |
922 | c->type = SSH_CHANNEL_OPEN; | |
d7ac5f18 | 923 | debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate); |
7368a6c8 | 924 | } |
925 | } | |
5260325f | 926 | |
28b9cb4d | 927 | /* try to decode a socks4 header */ |
396c147e | 928 | static int |
28b9cb4d | 929 | channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset) |
0490e609 | 930 | { |
661e45a0 | 931 | char *p, *host; |
2ceb8101 | 932 | u_int len, have, i, found; |
184eed6a | 933 | char username[256]; |
0490e609 | 934 | struct { |
935 | u_int8_t version; | |
936 | u_int8_t command; | |
937 | u_int16_t dest_port; | |
28b9cb4d | 938 | struct in_addr dest_addr; |
0490e609 | 939 | } s4_req, s4_rsp; |
940 | ||
28b9cb4d | 941 | debug2("channel %d: decode socks4", c->self); |
53b8fe68 | 942 | |
943 | have = buffer_len(&c->input); | |
944 | len = sizeof(s4_req); | |
945 | if (have < len) | |
946 | return 0; | |
947 | p = buffer_ptr(&c->input); | |
948 | for (found = 0, i = len; i < have; i++) { | |
949 | if (p[i] == '\0') { | |
950 | found = 1; | |
951 | break; | |
952 | } | |
953 | if (i > 1024) { | |
954 | /* the peer is probably sending garbage */ | |
955 | debug("channel %d: decode socks4: too long", | |
956 | c->self); | |
957 | return -1; | |
958 | } | |
959 | } | |
960 | if (!found) | |
961 | return 0; | |
0490e609 | 962 | buffer_get(&c->input, (char *)&s4_req.version, 1); |
963 | buffer_get(&c->input, (char *)&s4_req.command, 1); | |
964 | buffer_get(&c->input, (char *)&s4_req.dest_port, 2); | |
28b9cb4d | 965 | buffer_get(&c->input, (char *)&s4_req.dest_addr, 4); |
53b8fe68 | 966 | have = buffer_len(&c->input); |
0490e609 | 967 | p = buffer_ptr(&c->input); |
968 | len = strlen(p); | |
6683b40f | 969 | debug2("channel %d: decode socks4: user %s/%d", c->self, p, len); |
0490e609 | 970 | if (len > have) |
28b9cb4d | 971 | fatal("channel %d: decode socks4: len %d > have %d", |
0490e609 | 972 | c->self, len, have); |
973 | strlcpy(username, p, sizeof(username)); | |
974 | buffer_consume(&c->input, len); | |
975 | buffer_consume(&c->input, 1); /* trailing '\0' */ | |
976 | ||
28b9cb4d | 977 | host = inet_ntoa(s4_req.dest_addr); |
0490e609 | 978 | strlcpy(c->path, host, sizeof(c->path)); |
979 | c->host_port = ntohs(s4_req.dest_port); | |
184eed6a | 980 | |
d7ac5f18 | 981 | debug2("channel %d: dynamic request: socks4 host %s port %u command %u", |
6683b40f | 982 | c->self, host, c->host_port, s4_req.command); |
0490e609 | 983 | |
28b9cb4d | 984 | if (s4_req.command != 1) { |
985 | debug("channel %d: cannot handle: socks4 cn %d", | |
986 | c->self, s4_req.command); | |
987 | return -1; | |
0490e609 | 988 | } |
28b9cb4d | 989 | s4_rsp.version = 0; /* vn: 0 for reply */ |
990 | s4_rsp.command = 90; /* cd: req granted */ | |
0490e609 | 991 | s4_rsp.dest_port = 0; /* ignored */ |
28b9cb4d | 992 | s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */ |
0490e609 | 993 | buffer_append(&c->output, (char *)&s4_rsp, sizeof(s4_rsp)); |
28b9cb4d | 994 | return 1; |
0490e609 | 995 | } |
996 | ||
f49658f5 | 997 | /* try to decode a socks5 header */ |
998 | #define SSH_SOCKS5_AUTHDONE 0x1000 | |
999 | #define SSH_SOCKS5_NOAUTH 0x00 | |
1000 | #define SSH_SOCKS5_IPV4 0x01 | |
1001 | #define SSH_SOCKS5_DOMAIN 0x03 | |
1002 | #define SSH_SOCKS5_IPV6 0x04 | |
1003 | #define SSH_SOCKS5_CONNECT 0x01 | |
1004 | #define SSH_SOCKS5_SUCCESS 0x00 | |
1005 | ||
1006 | static int | |
1007 | channel_decode_socks5(Channel *c, fd_set * readset, fd_set * writeset) | |
1008 | { | |
1009 | struct { | |
1010 | u_int8_t version; | |
1011 | u_int8_t command; | |
1012 | u_int8_t reserved; | |
1013 | u_int8_t atyp; | |
1014 | } s5_req, s5_rsp; | |
1015 | u_int16_t dest_port; | |
1016 | u_char *p, dest_addr[255+1]; | |
2ceb8101 | 1017 | u_int have, i, found, nmethods, addrlen, af; |
f49658f5 | 1018 | |
1019 | debug2("channel %d: decode socks5", c->self); | |
1020 | p = buffer_ptr(&c->input); | |
1021 | if (p[0] != 0x05) | |
1022 | return -1; | |
1023 | have = buffer_len(&c->input); | |
1024 | if (!(c->flags & SSH_SOCKS5_AUTHDONE)) { | |
1025 | /* format: ver | nmethods | methods */ | |
aff51935 | 1026 | if (have < 2) |
f49658f5 | 1027 | return 0; |
1028 | nmethods = p[1]; | |
1029 | if (have < nmethods + 2) | |
1030 | return 0; | |
1031 | /* look for method: "NO AUTHENTICATION REQUIRED" */ | |
1032 | for (found = 0, i = 2 ; i < nmethods + 2; i++) { | |
1033 | if (p[i] == SSH_SOCKS5_NOAUTH ) { | |
1034 | found = 1; | |
1035 | break; | |
1036 | } | |
1037 | } | |
1038 | if (!found) { | |
1039 | debug("channel %d: method SSH_SOCKS5_NOAUTH not found", | |
1040 | c->self); | |
1041 | return -1; | |
1042 | } | |
1043 | buffer_consume(&c->input, nmethods + 2); | |
1044 | buffer_put_char(&c->output, 0x05); /* version */ | |
1045 | buffer_put_char(&c->output, SSH_SOCKS5_NOAUTH); /* method */ | |
1046 | FD_SET(c->sock, writeset); | |
1047 | c->flags |= SSH_SOCKS5_AUTHDONE; | |
1048 | debug2("channel %d: socks5 auth done", c->self); | |
1049 | return 0; /* need more */ | |
1050 | } | |
1051 | debug2("channel %d: socks5 post auth", c->self); | |
1052 | if (have < sizeof(s5_req)+1) | |
1053 | return 0; /* need more */ | |
1054 | memcpy((char *)&s5_req, p, sizeof(s5_req)); | |
1055 | if (s5_req.version != 0x05 || | |
1056 | s5_req.command != SSH_SOCKS5_CONNECT || | |
1057 | s5_req.reserved != 0x00) { | |
d7ac5f18 | 1058 | debug2("channel %d: only socks5 connect supported", c->self); |
f49658f5 | 1059 | return -1; |
1060 | } | |
f8cc7664 | 1061 | switch (s5_req.atyp){ |
f49658f5 | 1062 | case SSH_SOCKS5_IPV4: |
1063 | addrlen = 4; | |
1064 | af = AF_INET; | |
1065 | break; | |
1066 | case SSH_SOCKS5_DOMAIN: | |
1067 | addrlen = p[sizeof(s5_req)]; | |
1068 | af = -1; | |
1069 | break; | |
1070 | case SSH_SOCKS5_IPV6: | |
1071 | addrlen = 16; | |
1072 | af = AF_INET6; | |
1073 | break; | |
1074 | default: | |
d7ac5f18 | 1075 | debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp); |
f49658f5 | 1076 | return -1; |
1077 | } | |
1078 | if (have < 4 + addrlen + 2) | |
1079 | return 0; | |
1080 | buffer_consume(&c->input, sizeof(s5_req)); | |
1081 | if (s5_req.atyp == SSH_SOCKS5_DOMAIN) | |
1082 | buffer_consume(&c->input, 1); /* host string length */ | |
1083 | buffer_get(&c->input, (char *)&dest_addr, addrlen); | |
1084 | buffer_get(&c->input, (char *)&dest_port, 2); | |
1085 | dest_addr[addrlen] = '\0'; | |
1086 | if (s5_req.atyp == SSH_SOCKS5_DOMAIN) | |
f6be21a0 | 1087 | strlcpy(c->path, (char *)dest_addr, sizeof(c->path)); |
f49658f5 | 1088 | else if (inet_ntop(af, dest_addr, c->path, sizeof(c->path)) == NULL) |
1089 | return -1; | |
1090 | c->host_port = ntohs(dest_port); | |
b6453d99 | 1091 | |
d7ac5f18 | 1092 | debug2("channel %d: dynamic request: socks5 host %s port %u command %u", |
f49658f5 | 1093 | c->self, c->path, c->host_port, s5_req.command); |
1094 | ||
1095 | s5_rsp.version = 0x05; | |
1096 | s5_rsp.command = SSH_SOCKS5_SUCCESS; | |
1097 | s5_rsp.reserved = 0; /* ignored */ | |
1098 | s5_rsp.atyp = SSH_SOCKS5_IPV4; | |
1099 | ((struct in_addr *)&dest_addr)->s_addr = INADDR_ANY; | |
1100 | dest_port = 0; /* ignored */ | |
1101 | ||
1102 | buffer_append(&c->output, (char *)&s5_rsp, sizeof(s5_rsp)); | |
1103 | buffer_append(&c->output, (char *)&dest_addr, sizeof(struct in_addr)); | |
1104 | buffer_append(&c->output, (char *)&dest_port, sizeof(dest_port)); | |
1105 | return 1; | |
1106 | } | |
1107 | ||
28b9cb4d | 1108 | /* dynamic port forwarding */ |
396c147e | 1109 | static void |
28b9cb4d | 1110 | channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset) |
1111 | { | |
1112 | u_char *p; | |
2ceb8101 | 1113 | u_int have; |
1114 | int ret; | |
28b9cb4d | 1115 | |
1116 | have = buffer_len(&c->input); | |
639cb8ab | 1117 | c->delayed = 0; |
28b9cb4d | 1118 | debug2("channel %d: pre_dynamic: have %d", c->self, have); |
070adba2 | 1119 | /* buffer_dump(&c->input); */ |
28b9cb4d | 1120 | /* check if the fixed size part of the packet is in buffer. */ |
f49658f5 | 1121 | if (have < 3) { |
28b9cb4d | 1122 | /* need more */ |
1123 | FD_SET(c->sock, readset); | |
1124 | return; | |
1125 | } | |
1126 | /* try to guess the protocol */ | |
1127 | p = buffer_ptr(&c->input); | |
1128 | switch (p[0]) { | |
6683b40f | 1129 | case 0x04: |
1130 | ret = channel_decode_socks4(c, readset, writeset); | |
1131 | break; | |
f49658f5 | 1132 | case 0x05: |
1133 | ret = channel_decode_socks5(c, readset, writeset); | |
1134 | break; | |
28b9cb4d | 1135 | default: |
1136 | ret = -1; | |
1137 | break; | |
1138 | } | |
1139 | if (ret < 0) { | |
719fc62f | 1140 | chan_mark_dead(c); |
28b9cb4d | 1141 | } else if (ret == 0) { |
1142 | debug2("channel %d: pre_dynamic: need more", c->self); | |
1143 | /* need more */ | |
1144 | FD_SET(c->sock, readset); | |
1145 | } else { | |
1146 | /* switch to the next state */ | |
1147 | c->type = SSH_CHANNEL_OPENING; | |
1148 | port_open_helper(c, "direct-tcpip"); | |
1149 | } | |
1150 | } | |
0490e609 | 1151 | |
7368a6c8 | 1152 | /* This is our fake X11 server socket. */ |
396c147e | 1153 | static void |
7368a6c8 | 1154 | channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset) |
1155 | { | |
719fc62f | 1156 | Channel *nc; |
7368a6c8 | 1157 | struct sockaddr addr; |
bcc0381e | 1158 | int newsock; |
7368a6c8 | 1159 | socklen_t addrlen; |
865ac82e | 1160 | char buf[16384], *remote_ipaddr; |
0b242b12 | 1161 | int remote_port; |
7368a6c8 | 1162 | |
1163 | if (FD_ISSET(c->sock, readset)) { | |
1164 | debug("X11 connection requested."); | |
1165 | addrlen = sizeof(addr); | |
1166 | newsock = accept(c->sock, &addr, &addrlen); | |
ac151b18 | 1167 | if (c->single_connection) { |
d7ac5f18 | 1168 | debug2("single_connection: closing X11 listener."); |
ac151b18 | 1169 | channel_close_fd(&c->sock); |
1170 | chan_mark_dead(c); | |
1171 | } | |
7368a6c8 | 1172 | if (newsock < 0) { |
1173 | error("accept: %.100s", strerror(errno)); | |
1174 | return; | |
5260325f | 1175 | } |
bcc0381e | 1176 | set_nodelay(newsock); |
865ac82e | 1177 | remote_ipaddr = get_peer_ipaddr(newsock); |
0b242b12 | 1178 | remote_port = get_peer_port(newsock); |
7368a6c8 | 1179 | snprintf(buf, sizeof buf, "X11 connection from %.200s port %d", |
865ac82e | 1180 | remote_ipaddr, remote_port); |
0b242b12 | 1181 | |
719fc62f | 1182 | nc = channel_new("accepted x11 socket", |
0b242b12 | 1183 | SSH_CHANNEL_OPENING, newsock, newsock, -1, |
0d942eff | 1184 | c->local_window_max, c->local_maxpacket, 0, buf, 1); |
0b242b12 | 1185 | if (compat20) { |
1186 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
1187 | packet_put_cstring("x11"); | |
719fc62f | 1188 | packet_put_int(nc->self); |
ac151b18 | 1189 | packet_put_int(nc->local_window_max); |
1190 | packet_put_int(nc->local_maxpacket); | |
865ac82e | 1191 | /* originator ipaddr and port */ |
1192 | packet_put_cstring(remote_ipaddr); | |
d0c832f3 | 1193 | if (datafellows & SSH_BUG_X11FWD) { |
d7ac5f18 | 1194 | debug2("ssh2 x11 bug compat mode"); |
d0c832f3 | 1195 | } else { |
1196 | packet_put_int(remote_port); | |
1197 | } | |
0b242b12 | 1198 | packet_send(); |
1199 | } else { | |
1200 | packet_start(SSH_SMSG_X11_OPEN); | |
719fc62f | 1201 | packet_put_int(nc->self); |
8e7895b8 | 1202 | if (packet_get_protocol_flags() & |
1203 | SSH_PROTOFLAG_HOST_IN_FWD_OPEN) | |
449c5ba5 | 1204 | packet_put_cstring(buf); |
0b242b12 | 1205 | packet_send(); |
1206 | } | |
865ac82e | 1207 | xfree(remote_ipaddr); |
8efc0c15 | 1208 | } |
8efc0c15 | 1209 | } |
1210 | ||
396c147e | 1211 | static void |
0490e609 | 1212 | port_open_helper(Channel *c, char *rtype) |
1213 | { | |
1214 | int direct; | |
1215 | char buf[1024]; | |
1216 | char *remote_ipaddr = get_peer_ipaddr(c->sock); | |
29798ed0 | 1217 | int remote_port = get_peer_port(c->sock); |
0490e609 | 1218 | |
1219 | direct = (strcmp(rtype, "direct-tcpip") == 0); | |
1220 | ||
1221 | snprintf(buf, sizeof buf, | |
1222 | "%s: listening port %d for %.100s port %d, " | |
1223 | "connect from %.200s port %d", | |
1224 | rtype, c->listening_port, c->path, c->host_port, | |
1225 | remote_ipaddr, remote_port); | |
1226 | ||
1227 | xfree(c->remote_name); | |
1228 | c->remote_name = xstrdup(buf); | |
1229 | ||
1230 | if (compat20) { | |
1231 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
1232 | packet_put_cstring(rtype); | |
1233 | packet_put_int(c->self); | |
1234 | packet_put_int(c->local_window_max); | |
1235 | packet_put_int(c->local_maxpacket); | |
1236 | if (direct) { | |
1237 | /* target host, port */ | |
1238 | packet_put_cstring(c->path); | |
1239 | packet_put_int(c->host_port); | |
1240 | } else { | |
1241 | /* listen address, port */ | |
1242 | packet_put_cstring(c->path); | |
1243 | packet_put_int(c->listening_port); | |
1244 | } | |
1245 | /* originator host and port */ | |
1246 | packet_put_cstring(remote_ipaddr); | |
29798ed0 | 1247 | packet_put_int((u_int)remote_port); |
0490e609 | 1248 | packet_send(); |
1249 | } else { | |
1250 | packet_start(SSH_MSG_PORT_OPEN); | |
1251 | packet_put_int(c->self); | |
1252 | packet_put_cstring(c->path); | |
1253 | packet_put_int(c->host_port); | |
8e7895b8 | 1254 | if (packet_get_protocol_flags() & |
1255 | SSH_PROTOFLAG_HOST_IN_FWD_OPEN) | |
0490e609 | 1256 | packet_put_cstring(c->remote_name); |
1257 | packet_send(); | |
1258 | } | |
1259 | xfree(remote_ipaddr); | |
1260 | } | |
1261 | ||
442aee3a | 1262 | static void |
1263 | channel_set_reuseaddr(int fd) | |
1264 | { | |
1265 | int on = 1; | |
1266 | ||
1267 | /* | |
1268 | * Set socket options. | |
1269 | * Allow local port reuse in TIME_WAIT. | |
1270 | */ | |
1271 | if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1) | |
1272 | error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno)); | |
1273 | } | |
1274 | ||
aa3378df | 1275 | /* |
7368a6c8 | 1276 | * This socket is listening for connections to a forwarded TCP/IP port. |
aa3378df | 1277 | */ |
396c147e | 1278 | static void |
7368a6c8 | 1279 | channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset) |
1280 | { | |
0490e609 | 1281 | Channel *nc; |
7368a6c8 | 1282 | struct sockaddr addr; |
719fc62f | 1283 | int newsock, nextstate; |
7368a6c8 | 1284 | socklen_t addrlen; |
0490e609 | 1285 | char *rtype; |
fa08c86b | 1286 | |
7368a6c8 | 1287 | if (FD_ISSET(c->sock, readset)) { |
1288 | debug("Connection to port %d forwarding " | |
1289 | "to %.100s port %d requested.", | |
1290 | c->listening_port, c->path, c->host_port); | |
0490e609 | 1291 | |
639cb8ab | 1292 | if (c->type == SSH_CHANNEL_RPORT_LISTENER) { |
1293 | nextstate = SSH_CHANNEL_OPENING; | |
1294 | rtype = "forwarded-tcpip"; | |
1295 | } else { | |
1296 | if (c->host_port == 0) { | |
1297 | nextstate = SSH_CHANNEL_DYNAMIC; | |
f3964cb9 | 1298 | rtype = "dynamic-tcpip"; |
639cb8ab | 1299 | } else { |
1300 | nextstate = SSH_CHANNEL_OPENING; | |
1301 | rtype = "direct-tcpip"; | |
1302 | } | |
1303 | } | |
0490e609 | 1304 | |
7368a6c8 | 1305 | addrlen = sizeof(addr); |
1306 | newsock = accept(c->sock, &addr, &addrlen); | |
1307 | if (newsock < 0) { | |
1308 | error("accept: %.100s", strerror(errno)); | |
1309 | return; | |
1310 | } | |
811a6342 | 1311 | set_nodelay(newsock); |
0d942eff | 1312 | nc = channel_new(rtype, nextstate, newsock, newsock, -1, |
1313 | c->local_window_max, c->local_maxpacket, 0, rtype, 1); | |
0490e609 | 1314 | nc->listening_port = c->listening_port; |
1315 | nc->host_port = c->host_port; | |
1316 | strlcpy(nc->path, c->path, sizeof(nc->path)); | |
1317 | ||
639cb8ab | 1318 | if (nextstate == SSH_CHANNEL_DYNAMIC) { |
1319 | /* | |
1320 | * do not call the channel_post handler until | |
1321 | * this flag has been reset by a pre-handler. | |
1322 | * otherwise the FD_ISSET calls might overflow | |
1323 | */ | |
1324 | nc->delayed = 1; | |
1325 | } else { | |
0490e609 | 1326 | port_open_helper(nc, rtype); |
639cb8ab | 1327 | } |
7368a6c8 | 1328 | } |
1329 | } | |
8efc0c15 | 1330 | |
7368a6c8 | 1331 | /* |
1332 | * This is the authentication agent socket listening for connections from | |
1333 | * clients. | |
1334 | */ | |
396c147e | 1335 | static void |
7368a6c8 | 1336 | channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset) |
8efc0c15 | 1337 | { |
719fc62f | 1338 | Channel *nc; |
1339 | int newsock; | |
5260325f | 1340 | struct sockaddr addr; |
48e671d5 | 1341 | socklen_t addrlen; |
5260325f | 1342 | |
7368a6c8 | 1343 | if (FD_ISSET(c->sock, readset)) { |
1344 | addrlen = sizeof(addr); | |
1345 | newsock = accept(c->sock, &addr, &addrlen); | |
1346 | if (newsock < 0) { | |
1347 | error("accept from auth socket: %.100s", strerror(errno)); | |
1348 | return; | |
1349 | } | |
719fc62f | 1350 | nc = channel_new("accepted auth socket", |
fa08c86b | 1351 | SSH_CHANNEL_OPENING, newsock, newsock, -1, |
1352 | c->local_window_max, c->local_maxpacket, | |
0d942eff | 1353 | 0, "accepted auth socket", 1); |
fa08c86b | 1354 | if (compat20) { |
1355 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
1356 | packet_put_cstring("auth-agent@openssh.com"); | |
719fc62f | 1357 | packet_put_int(nc->self); |
fa08c86b | 1358 | packet_put_int(c->local_window_max); |
1359 | packet_put_int(c->local_maxpacket); | |
1360 | } else { | |
1361 | packet_start(SSH_SMSG_AGENT_OPEN); | |
719fc62f | 1362 | packet_put_int(nc->self); |
fa08c86b | 1363 | } |
7368a6c8 | 1364 | packet_send(); |
1365 | } | |
1366 | } | |
5260325f | 1367 | |
396c147e | 1368 | static void |
97fb6912 | 1369 | channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset) |
1370 | { | |
d18e0850 | 1371 | int err = 0; |
8ab2cb35 | 1372 | socklen_t sz = sizeof(err); |
d18e0850 | 1373 | |
97fb6912 | 1374 | if (FD_ISSET(c->sock, writeset)) { |
db518d9b | 1375 | if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) { |
d18e0850 | 1376 | err = errno; |
1377 | error("getsockopt SO_ERROR failed"); | |
1378 | } | |
1379 | if (err == 0) { | |
1380 | debug("channel %d: connected", c->self); | |
1381 | c->type = SSH_CHANNEL_OPEN; | |
1382 | if (compat20) { | |
1383 | packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1384 | packet_put_int(c->remote_id); | |
1385 | packet_put_int(c->self); | |
1386 | packet_put_int(c->local_window); | |
1387 | packet_put_int(c->local_maxpacket); | |
1388 | } else { | |
1389 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1390 | packet_put_int(c->remote_id); | |
1391 | packet_put_int(c->self); | |
1392 | } | |
97fb6912 | 1393 | } else { |
d18e0850 | 1394 | debug("channel %d: not connected: %s", |
1395 | c->self, strerror(err)); | |
1396 | if (compat20) { | |
1397 | packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE); | |
1398 | packet_put_int(c->remote_id); | |
1399 | packet_put_int(SSH2_OPEN_CONNECT_FAILED); | |
1400 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { | |
1401 | packet_put_cstring(strerror(err)); | |
1402 | packet_put_cstring(""); | |
1403 | } | |
97fb6912 | 1404 | } else { |
d18e0850 | 1405 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); |
1406 | packet_put_int(c->remote_id); | |
97fb6912 | 1407 | } |
d18e0850 | 1408 | chan_mark_dead(c); |
97fb6912 | 1409 | } |
d18e0850 | 1410 | packet_send(); |
97fb6912 | 1411 | } |
1412 | } | |
1413 | ||
396c147e | 1414 | static int |
7368a6c8 | 1415 | channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset) |
1416 | { | |
fa1d7d85 | 1417 | char buf[CHAN_RBUF]; |
7368a6c8 | 1418 | int len; |
1419 | ||
6fd8622b | 1420 | if (c->rfd != -1 && |
7368a6c8 | 1421 | FD_ISSET(c->rfd, readset)) { |
1422 | len = read(c->rfd, buf, sizeof(buf)); | |
0fbe8c74 | 1423 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1424 | return 1; | |
7368a6c8 | 1425 | if (len <= 0) { |
d7ac5f18 | 1426 | debug2("channel %d: read<=0 rfd %d len %d", |
7368a6c8 | 1427 | c->self, c->rfd, len); |
28b9cb4d | 1428 | if (c->type != SSH_CHANNEL_OPEN) { |
d7ac5f18 | 1429 | debug2("channel %d: not open", c->self); |
719fc62f | 1430 | chan_mark_dead(c); |
0490e609 | 1431 | return -1; |
28b9cb4d | 1432 | } else if (compat13) { |
9c50edcf | 1433 | buffer_clear(&c->output); |
7368a6c8 | 1434 | c->type = SSH_CHANNEL_INPUT_DRAINING; |
d7ac5f18 | 1435 | debug2("channel %d: input draining.", c->self); |
7368a6c8 | 1436 | } else { |
1437 | chan_read_failed(c); | |
5260325f | 1438 | } |
7368a6c8 | 1439 | return -1; |
1440 | } | |
6aacefa7 | 1441 | if (c->input_filter != NULL) { |
2e73a022 | 1442 | if (c->input_filter(c, buf, len) == -1) { |
d7ac5f18 | 1443 | debug2("channel %d: filter stops", c->self); |
2e73a022 | 1444 | chan_read_failed(c); |
1445 | } | |
d20f3c9e | 1446 | } else if (c->datagram) { |
1447 | buffer_put_string(&c->input, buf, len); | |
2e73a022 | 1448 | } else { |
1449 | buffer_append(&c->input, buf, len); | |
1450 | } | |
7368a6c8 | 1451 | } |
1452 | return 1; | |
1453 | } | |
396c147e | 1454 | static int |
7368a6c8 | 1455 | channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset) |
1456 | { | |
95ce5599 | 1457 | struct termios tio; |
c1c6a032 | 1458 | u_char *data = NULL, *buf; |
780a9951 | 1459 | u_int dlen; |
7368a6c8 | 1460 | int len; |
1461 | ||
1462 | /* Send buffered output data to the socket. */ | |
6fd8622b | 1463 | if (c->wfd != -1 && |
7368a6c8 | 1464 | FD_ISSET(c->wfd, writeset) && |
1465 | buffer_len(&c->output) > 0) { | |
c1c6a032 | 1466 | if (c->output_filter != NULL) { |
1467 | if ((buf = c->output_filter(c, &data, &dlen)) == NULL) { | |
1468 | debug2("channel %d: filter stops", c->self); | |
d7b37427 | 1469 | if (c->type != SSH_CHANNEL_OPEN) |
1470 | chan_mark_dead(c); | |
1471 | else | |
1472 | chan_write_failed(c); | |
1473 | return -1; | |
c1c6a032 | 1474 | } |
1475 | } else if (c->datagram) { | |
1476 | buf = data = buffer_get_string(&c->output, &dlen); | |
1477 | } else { | |
1478 | buf = data = buffer_ptr(&c->output); | |
1479 | dlen = buffer_len(&c->output); | |
1480 | } | |
1481 | ||
d20f3c9e | 1482 | if (c->datagram) { |
d20f3c9e | 1483 | /* ignore truncated writes, datagrams might get lost */ |
1484 | c->local_consumed += dlen + 4; | |
c1c6a032 | 1485 | len = write(c->wfd, buf, dlen); |
d20f3c9e | 1486 | xfree(data); |
1487 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) | |
1488 | return 1; | |
1489 | if (len <= 0) { | |
1490 | if (c->type != SSH_CHANNEL_OPEN) | |
1491 | chan_mark_dead(c); | |
1492 | else | |
1493 | chan_write_failed(c); | |
1494 | return -1; | |
1495 | } | |
1496 | return 1; | |
1497 | } | |
64c0ce80 | 1498 | #ifdef _AIX |
aff51935 | 1499 | /* XXX: Later AIX versions can't push as much data to tty */ |
7fbb4189 | 1500 | if (compat20 && c->wfd_isatty) |
1501 | dlen = MIN(dlen, 8*1024); | |
64c0ce80 | 1502 | #endif |
c1c6a032 | 1503 | |
1504 | len = write(c->wfd, buf, dlen); | |
0fbe8c74 | 1505 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1506 | return 1; | |
7368a6c8 | 1507 | if (len <= 0) { |
28b9cb4d | 1508 | if (c->type != SSH_CHANNEL_OPEN) { |
d7ac5f18 | 1509 | debug2("channel %d: not open", c->self); |
719fc62f | 1510 | chan_mark_dead(c); |
28b9cb4d | 1511 | return -1; |
1512 | } else if (compat13) { | |
9c50edcf | 1513 | buffer_clear(&c->output); |
d7ac5f18 | 1514 | debug2("channel %d: input draining.", c->self); |
7368a6c8 | 1515 | c->type = SSH_CHANNEL_INPUT_DRAINING; |
1516 | } else { | |
1517 | chan_write_failed(c); | |
5260325f | 1518 | } |
7368a6c8 | 1519 | return -1; |
1520 | } | |
c1c6a032 | 1521 | if (compat20 && c->isatty && dlen >= 1 && buf[0] != '\r') { |
0ae4fe1d | 1522 | if (tcgetattr(c->wfd, &tio) == 0 && |
1523 | !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) { | |
1524 | /* | |
1525 | * Simulate echo to reduce the impact of | |
355724fc | 1526 | * traffic analysis. We need to match the |
95ce5599 | 1527 | * size of a SSH2_MSG_CHANNEL_DATA message |
c1c6a032 | 1528 | * (4 byte channel id + buf) |
0ae4fe1d | 1529 | */ |
95ce5599 | 1530 | packet_send_ignore(4 + len); |
0ae4fe1d | 1531 | packet_send(); |
0ae4fe1d | 1532 | } |
1533 | } | |
7368a6c8 | 1534 | buffer_consume(&c->output, len); |
7e7327a1 | 1535 | if (compat20 && len > 0) { |
1536 | c->local_consumed += len; | |
1537 | } | |
1538 | } | |
1539 | return 1; | |
1540 | } | |
396c147e | 1541 | static int |
7e7327a1 | 1542 | channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset) |
1543 | { | |
fa1d7d85 | 1544 | char buf[CHAN_RBUF]; |
7e7327a1 | 1545 | int len; |
1546 | ||
8ce64345 | 1547 | /** XXX handle drain efd, too */ |
7e7327a1 | 1548 | if (c->efd != -1) { |
1549 | if (c->extended_usage == CHAN_EXTENDED_WRITE && | |
1550 | FD_ISSET(c->efd, writeset) && | |
1551 | buffer_len(&c->extended) > 0) { | |
1552 | len = write(c->efd, buffer_ptr(&c->extended), | |
1553 | buffer_len(&c->extended)); | |
de273eef | 1554 | debug2("channel %d: written %d to efd %d", |
7e7327a1 | 1555 | c->self, len, c->efd); |
ee55dacf | 1556 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1557 | return 1; | |
1558 | if (len <= 0) { | |
1559 | debug2("channel %d: closing write-efd %d", | |
1560 | c->self, c->efd); | |
489aa2e9 | 1561 | channel_close_fd(&c->efd); |
ee55dacf | 1562 | } else { |
7e7327a1 | 1563 | buffer_consume(&c->extended, len); |
1564 | c->local_consumed += len; | |
1565 | } | |
1566 | } else if (c->extended_usage == CHAN_EXTENDED_READ && | |
1567 | FD_ISSET(c->efd, readset)) { | |
1568 | len = read(c->efd, buf, sizeof(buf)); | |
de273eef | 1569 | debug2("channel %d: read %d from efd %d", |
184eed6a | 1570 | c->self, len, c->efd); |
ee55dacf | 1571 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1572 | return 1; | |
1573 | if (len <= 0) { | |
1574 | debug2("channel %d: closing read-efd %d", | |
8ce64345 | 1575 | c->self, c->efd); |
489aa2e9 | 1576 | channel_close_fd(&c->efd); |
ee55dacf | 1577 | } else { |
7e7327a1 | 1578 | buffer_append(&c->extended, buf, len); |
ee55dacf | 1579 | } |
7e7327a1 | 1580 | } |
1581 | } | |
1582 | return 1; | |
1583 | } | |
396c147e | 1584 | static int |
5e96b616 | 1585 | channel_handle_ctl(Channel *c, fd_set * readset, fd_set * writeset) |
1586 | { | |
1587 | char buf[16]; | |
1588 | int len; | |
1589 | ||
1590 | /* Monitor control fd to detect if the slave client exits */ | |
1591 | if (c->ctl_fd != -1 && FD_ISSET(c->ctl_fd, readset)) { | |
1592 | len = read(c->ctl_fd, buf, sizeof(buf)); | |
1593 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) | |
1594 | return 1; | |
1595 | if (len <= 0) { | |
1596 | debug2("channel %d: ctl read<=0", c->self); | |
1597 | if (c->type != SSH_CHANNEL_OPEN) { | |
1598 | debug2("channel %d: not open", c->self); | |
1599 | chan_mark_dead(c); | |
1600 | return -1; | |
1601 | } else { | |
1602 | chan_read_failed(c); | |
1603 | chan_write_failed(c); | |
1604 | } | |
1605 | return -1; | |
1606 | } else | |
1607 | fatal("%s: unexpected data on ctl fd", __func__); | |
1608 | } | |
1609 | return 1; | |
1610 | } | |
1611 | static int | |
ee55dacf | 1612 | channel_check_window(Channel *c) |
7e7327a1 | 1613 | { |
28b9cb4d | 1614 | if (c->type == SSH_CHANNEL_OPEN && |
1615 | !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) && | |
7e7327a1 | 1616 | c->local_window < c->local_window_max/2 && |
1617 | c->local_consumed > 0) { | |
1618 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); | |
1619 | packet_put_int(c->remote_id); | |
1620 | packet_put_int(c->local_consumed); | |
1621 | packet_send(); | |
de273eef | 1622 | debug2("channel %d: window %d sent adjust %d", |
7e7327a1 | 1623 | c->self, c->local_window, |
1624 | c->local_consumed); | |
1625 | c->local_window += c->local_consumed; | |
1626 | c->local_consumed = 0; | |
7368a6c8 | 1627 | } |
1628 | return 1; | |
1629 | } | |
5260325f | 1630 | |
396c147e | 1631 | static void |
0c0738d5 | 1632 | channel_post_open(Channel *c, fd_set * readset, fd_set * writeset) |
7368a6c8 | 1633 | { |
639cb8ab | 1634 | if (c->delayed) |
1635 | return; | |
7368a6c8 | 1636 | channel_handle_rfd(c, readset, writeset); |
1637 | channel_handle_wfd(c, readset, writeset); | |
0c0738d5 | 1638 | if (!compat20) |
639cb8ab | 1639 | return; |
7e7327a1 | 1640 | channel_handle_efd(c, readset, writeset); |
5e96b616 | 1641 | channel_handle_ctl(c, readset, writeset); |
ee55dacf | 1642 | channel_check_window(c); |
7e7327a1 | 1643 | } |
1644 | ||
396c147e | 1645 | static void |
7368a6c8 | 1646 | channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset) |
1647 | { | |
1648 | int len; | |
e1feb9bf | 1649 | |
7368a6c8 | 1650 | /* Send buffered output data to the socket. */ |
1651 | if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) { | |
1652 | len = write(c->sock, buffer_ptr(&c->output), | |
1653 | buffer_len(&c->output)); | |
1654 | if (len <= 0) | |
9c50edcf | 1655 | buffer_clear(&c->output); |
7368a6c8 | 1656 | else |
1657 | buffer_consume(&c->output, len); | |
1658 | } | |
1659 | } | |
5260325f | 1660 | |
396c147e | 1661 | static void |
7e7327a1 | 1662 | channel_handler_init_20(void) |
1663 | { | |
0c0738d5 | 1664 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open; |
0b242b12 | 1665 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; |
7e7327a1 | 1666 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; |
fa08c86b | 1667 | channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener; |
0b242b12 | 1668 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; |
fa08c86b | 1669 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; |
97fb6912 | 1670 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1671 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7e7327a1 | 1672 | |
0c0738d5 | 1673 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open; |
7e7327a1 | 1674 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; |
fa08c86b | 1675 | channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener; |
0b242b12 | 1676 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; |
fa08c86b | 1677 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; |
97fb6912 | 1678 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
0c0738d5 | 1679 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open; |
7e7327a1 | 1680 | } |
1681 | ||
396c147e | 1682 | static void |
7368a6c8 | 1683 | channel_handler_init_13(void) |
1684 | { | |
1685 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13; | |
1686 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13; | |
1687 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; | |
1688 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; | |
1689 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; | |
1690 | channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining; | |
1691 | channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining; | |
97fb6912 | 1692 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1693 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7368a6c8 | 1694 | |
0c0738d5 | 1695 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open; |
7368a6c8 | 1696 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; |
1697 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
1698 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; | |
1699 | channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13; | |
97fb6912 | 1700 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
0c0738d5 | 1701 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open; |
7368a6c8 | 1702 | } |
5260325f | 1703 | |
396c147e | 1704 | static void |
7368a6c8 | 1705 | channel_handler_init_15(void) |
1706 | { | |
0c0738d5 | 1707 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open; |
0b242b12 | 1708 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; |
7368a6c8 | 1709 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; |
1710 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; | |
1711 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; | |
97fb6912 | 1712 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1713 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7368a6c8 | 1714 | |
1715 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; | |
1716 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
1717 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; | |
0c0738d5 | 1718 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open; |
97fb6912 | 1719 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
0c0738d5 | 1720 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open; |
7368a6c8 | 1721 | } |
1722 | ||
396c147e | 1723 | static void |
7368a6c8 | 1724 | channel_handler_init(void) |
1725 | { | |
1726 | int i; | |
e1feb9bf | 1727 | |
184eed6a | 1728 | for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) { |
7368a6c8 | 1729 | channel_pre[i] = NULL; |
1730 | channel_post[i] = NULL; | |
1731 | } | |
7e7327a1 | 1732 | if (compat20) |
1733 | channel_handler_init_20(); | |
1734 | else if (compat13) | |
7368a6c8 | 1735 | channel_handler_init_13(); |
1736 | else | |
1737 | channel_handler_init_15(); | |
1738 | } | |
1739 | ||
418e724c | 1740 | /* gc dead channels */ |
1741 | static void | |
1742 | channel_garbage_collect(Channel *c) | |
1743 | { | |
1744 | if (c == NULL) | |
1745 | return; | |
1746 | if (c->detach_user != NULL) { | |
8cd0437d | 1747 | if (!chan_is_dead(c, c->detach_close)) |
418e724c | 1748 | return; |
d7ac5f18 | 1749 | debug2("channel %d: gc: notify user", c->self); |
418e724c | 1750 | c->detach_user(c->self, NULL); |
1751 | /* if we still have a callback */ | |
1752 | if (c->detach_user != NULL) | |
1753 | return; | |
d7ac5f18 | 1754 | debug2("channel %d: gc: user detached", c->self); |
418e724c | 1755 | } |
1756 | if (!chan_is_dead(c, 1)) | |
1757 | return; | |
d7ac5f18 | 1758 | debug2("channel %d: garbage collecting", c->self); |
418e724c | 1759 | channel_free(c); |
1760 | } | |
1761 | ||
396c147e | 1762 | static void |
7368a6c8 | 1763 | channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset) |
1764 | { | |
1765 | static int did_init = 0; | |
9a995072 | 1766 | u_int i; |
7368a6c8 | 1767 | Channel *c; |
1768 | ||
1769 | if (!did_init) { | |
1770 | channel_handler_init(); | |
1771 | did_init = 1; | |
1772 | } | |
1773 | for (i = 0; i < channels_alloc; i++) { | |
719fc62f | 1774 | c = channels[i]; |
1775 | if (c == NULL) | |
5260325f | 1776 | continue; |
6fd8622b | 1777 | if (ftab[c->type] != NULL) |
1778 | (*ftab[c->type])(c, readset, writeset); | |
418e724c | 1779 | channel_garbage_collect(c); |
8efc0c15 | 1780 | } |
8efc0c15 | 1781 | } |
1782 | ||
8e7895b8 | 1783 | /* |
1784 | * Allocate/update select bitmasks and add any bits relevant to channels in | |
1785 | * select bitmasks. | |
1786 | */ | |
6ae2364d | 1787 | void |
c422989b | 1788 | channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp, |
9a995072 | 1789 | u_int *nallocp, int rekeying) |
7368a6c8 | 1790 | { |
9a995072 | 1791 | u_int n, sz; |
39929cdb | 1792 | |
1793 | n = MAX(*maxfdp, channel_max_fd); | |
1794 | ||
1795 | sz = howmany(n+1, NFDBITS) * sizeof(fd_mask); | |
489aa2e9 | 1796 | /* perhaps check sz < nalloc/2 and shrink? */ |
1797 | if (*readsetp == NULL || sz > *nallocp) { | |
1798 | *readsetp = xrealloc(*readsetp, sz); | |
1799 | *writesetp = xrealloc(*writesetp, sz); | |
1800 | *nallocp = sz; | |
39929cdb | 1801 | } |
489aa2e9 | 1802 | *maxfdp = n; |
39929cdb | 1803 | memset(*readsetp, 0, sz); |
1804 | memset(*writesetp, 0, sz); | |
1805 | ||
c422989b | 1806 | if (!rekeying) |
1807 | channel_handler(channel_pre, *readsetp, *writesetp); | |
7368a6c8 | 1808 | } |
1809 | ||
8e7895b8 | 1810 | /* |
1811 | * After select, perform any appropriate operations for channels which have | |
1812 | * events pending. | |
1813 | */ | |
6ae2364d | 1814 | void |
7368a6c8 | 1815 | channel_after_select(fd_set * readset, fd_set * writeset) |
1816 | { | |
1817 | channel_handler(channel_post, readset, writeset); | |
1818 | } | |
1819 | ||
8e7895b8 | 1820 | |
39929cdb | 1821 | /* If there is data to send to the connection, enqueue some of it now. */ |
8efc0c15 | 1822 | |
6ae2364d | 1823 | void |
d5bb9418 | 1824 | channel_output_poll(void) |
8efc0c15 | 1825 | { |
7368a6c8 | 1826 | Channel *c; |
9a995072 | 1827 | u_int i, len; |
5260325f | 1828 | |
1829 | for (i = 0; i < channels_alloc; i++) { | |
719fc62f | 1830 | c = channels[i]; |
1831 | if (c == NULL) | |
1832 | continue; | |
48e671d5 | 1833 | |
8e7895b8 | 1834 | /* |
1835 | * We are only interested in channels that can have buffered | |
1836 | * incoming data. | |
1837 | */ | |
48e671d5 | 1838 | if (compat13) { |
7368a6c8 | 1839 | if (c->type != SSH_CHANNEL_OPEN && |
1840 | c->type != SSH_CHANNEL_INPUT_DRAINING) | |
48e671d5 | 1841 | continue; |
1842 | } else { | |
7368a6c8 | 1843 | if (c->type != SSH_CHANNEL_OPEN) |
48e671d5 | 1844 | continue; |
48e671d5 | 1845 | } |
e78a59f5 | 1846 | if (compat20 && |
1847 | (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) { | |
ee55dacf | 1848 | /* XXX is this true? */ |
418e724c | 1849 | debug3("channel %d: will not send data after close", c->self); |
7e7327a1 | 1850 | continue; |
1851 | } | |
5260325f | 1852 | |
1853 | /* Get the amount of buffered data for this channel. */ | |
ee55dacf | 1854 | if ((c->istate == CHAN_INPUT_OPEN || |
1855 | c->istate == CHAN_INPUT_WAIT_DRAIN) && | |
1856 | (len = buffer_len(&c->input)) > 0) { | |
d20f3c9e | 1857 | if (c->datagram) { |
1858 | if (len > 0) { | |
1859 | u_char *data; | |
1860 | u_int dlen; | |
1861 | ||
1862 | data = buffer_get_string(&c->input, | |
1863 | &dlen); | |
1864 | packet_start(SSH2_MSG_CHANNEL_DATA); | |
1865 | packet_put_int(c->remote_id); | |
1866 | packet_put_string(data, dlen); | |
1867 | packet_send(); | |
1868 | c->remote_window -= dlen + 4; | |
1869 | xfree(data); | |
1870 | } | |
1871 | continue; | |
1872 | } | |
8e7895b8 | 1873 | /* |
1874 | * Send some data for the other side over the secure | |
1875 | * connection. | |
1876 | */ | |
7e7327a1 | 1877 | if (compat20) { |
1878 | if (len > c->remote_window) | |
1879 | len = c->remote_window; | |
1880 | if (len > c->remote_maxpacket) | |
1881 | len = c->remote_maxpacket; | |
5260325f | 1882 | } else { |
7e7327a1 | 1883 | if (packet_is_interactive()) { |
1884 | if (len > 1024) | |
1885 | len = 512; | |
1886 | } else { | |
1887 | /* Keep the packets at reasonable size. */ | |
1888 | if (len > packet_get_maxsize()/2) | |
1889 | len = packet_get_maxsize()/2; | |
1890 | } | |
5260325f | 1891 | } |
7368a6c8 | 1892 | if (len > 0) { |
7e7327a1 | 1893 | packet_start(compat20 ? |
1894 | SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA); | |
7368a6c8 | 1895 | packet_put_int(c->remote_id); |
1896 | packet_put_string(buffer_ptr(&c->input), len); | |
1897 | packet_send(); | |
1898 | buffer_consume(&c->input, len); | |
1899 | c->remote_window -= len; | |
7368a6c8 | 1900 | } |
1901 | } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) { | |
5260325f | 1902 | if (compat13) |
1903 | fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3"); | |
aa3378df | 1904 | /* |
1905 | * input-buffer is empty and read-socket shutdown: | |
d2296ed7 | 1906 | * tell peer, that we will not send more data: send IEOF. |
1907 | * hack for extended data: delay EOF if EFD still in use. | |
aa3378df | 1908 | */ |
d2296ed7 | 1909 | if (CHANNEL_EFD_INPUT_ACTIVE(c)) |
4e2e5cfd | 1910 | debug2("channel %d: ibuf_empty delayed efd %d/(%d)", |
1911 | c->self, c->efd, buffer_len(&c->extended)); | |
d2296ed7 | 1912 | else |
1913 | chan_ibuf_empty(c); | |
5260325f | 1914 | } |
7e7327a1 | 1915 | /* Send extended data, i.e. stderr */ |
1916 | if (compat20 && | |
d2296ed7 | 1917 | !(c->flags & CHAN_EOF_SENT) && |
7e7327a1 | 1918 | c->remote_window > 0 && |
1919 | (len = buffer_len(&c->extended)) > 0 && | |
1920 | c->extended_usage == CHAN_EXTENDED_READ) { | |
f91d9a89 | 1921 | debug2("channel %d: rwin %u elen %u euse %d", |
ee55dacf | 1922 | c->self, c->remote_window, buffer_len(&c->extended), |
1923 | c->extended_usage); | |
7e7327a1 | 1924 | if (len > c->remote_window) |
1925 | len = c->remote_window; | |
1926 | if (len > c->remote_maxpacket) | |
1927 | len = c->remote_maxpacket; | |
1928 | packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA); | |
1929 | packet_put_int(c->remote_id); | |
1930 | packet_put_int(SSH2_EXTENDED_DATA_STDERR); | |
1931 | packet_put_string(buffer_ptr(&c->extended), len); | |
1932 | packet_send(); | |
1933 | buffer_consume(&c->extended, len); | |
1934 | c->remote_window -= len; | |
ee55dacf | 1935 | debug2("channel %d: sent ext data %d", c->self, len); |
7e7327a1 | 1936 | } |
8efc0c15 | 1937 | } |
8efc0c15 | 1938 | } |
1939 | ||
8e7895b8 | 1940 | |
1941 | /* -- protocol input */ | |
8efc0c15 | 1942 | |
6ae2364d | 1943 | void |
7819b5c3 | 1944 | channel_input_data(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 1945 | { |
48e671d5 | 1946 | int id; |
5260325f | 1947 | char *data; |
1e3b8b07 | 1948 | u_int data_len; |
7368a6c8 | 1949 | Channel *c; |
5260325f | 1950 | |
1951 | /* Get the channel number and verify it. */ | |
48e671d5 | 1952 | id = packet_get_int(); |
7368a6c8 | 1953 | c = channel_lookup(id); |
1954 | if (c == NULL) | |
48e671d5 | 1955 | packet_disconnect("Received data for nonexistent channel %d.", id); |
5260325f | 1956 | |
1957 | /* Ignore any data for non-open channels (might happen on close) */ | |
7368a6c8 | 1958 | if (c->type != SSH_CHANNEL_OPEN && |
1959 | c->type != SSH_CHANNEL_X11_OPEN) | |
48e671d5 | 1960 | return; |
1961 | ||
5260325f | 1962 | /* Get the data. */ |
1963 | data = packet_get_string(&data_len); | |
7368a6c8 | 1964 | |
7741e239 | 1965 | /* |
1966 | * Ignore data for protocol > 1.3 if output end is no longer open. | |
1967 | * For protocol 2 the sending side is reducing its window as it sends | |
1968 | * data, so we must 'fake' consumption of the data in order to ensure | |
1969 | * that window updates are sent back. Otherwise the connection might | |
1970 | * deadlock. | |
1971 | */ | |
1972 | if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) { | |
1973 | if (compat20) { | |
1974 | c->local_window -= data_len; | |
1975 | c->local_consumed += data_len; | |
1976 | } | |
1977 | xfree(data); | |
1978 | return; | |
1979 | } | |
1980 | ||
6aacefa7 | 1981 | if (compat20) { |
7e7327a1 | 1982 | if (data_len > c->local_maxpacket) { |
bbe88b6d | 1983 | logit("channel %d: rcvd big packet %d, maxpack %d", |
7e7327a1 | 1984 | c->self, data_len, c->local_maxpacket); |
1985 | } | |
1986 | if (data_len > c->local_window) { | |
bbe88b6d | 1987 | logit("channel %d: rcvd too much data %d, win %d", |
7e7327a1 | 1988 | c->self, data_len, c->local_window); |
1989 | xfree(data); | |
1990 | return; | |
1991 | } | |
1992 | c->local_window -= data_len; | |
7e7327a1 | 1993 | } |
95500969 | 1994 | packet_check_eom(); |
d20f3c9e | 1995 | if (c->datagram) |
1996 | buffer_put_string(&c->output, data, data_len); | |
1997 | else | |
1998 | buffer_append(&c->output, data, data_len); | |
5260325f | 1999 | xfree(data); |
8efc0c15 | 2000 | } |
8e7895b8 | 2001 | |
6ae2364d | 2002 | void |
7819b5c3 | 2003 | channel_input_extended_data(int type, u_int32_t seq, void *ctxt) |
7e7327a1 | 2004 | { |
2005 | int id; | |
7e7327a1 | 2006 | char *data; |
a594fa74 | 2007 | u_int data_len, tcode; |
7e7327a1 | 2008 | Channel *c; |
2009 | ||
2010 | /* Get the channel number and verify it. */ | |
2011 | id = packet_get_int(); | |
2012 | c = channel_lookup(id); | |
2013 | ||
2014 | if (c == NULL) | |
2015 | packet_disconnect("Received extended_data for bad channel %d.", id); | |
2016 | if (c->type != SSH_CHANNEL_OPEN) { | |
bbe88b6d | 2017 | logit("channel %d: ext data for non open", id); |
7e7327a1 | 2018 | return; |
2019 | } | |
d2296ed7 | 2020 | if (c->flags & CHAN_EOF_RCVD) { |
2021 | if (datafellows & SSH_BUG_EXTEOF) | |
2022 | debug("channel %d: accepting ext data after eof", id); | |
2023 | else | |
2024 | packet_disconnect("Received extended_data after EOF " | |
2025 | "on channel %d.", id); | |
2026 | } | |
7e7327a1 | 2027 | tcode = packet_get_int(); |
2028 | if (c->efd == -1 || | |
2029 | c->extended_usage != CHAN_EXTENDED_WRITE || | |
2030 | tcode != SSH2_EXTENDED_DATA_STDERR) { | |
bbe88b6d | 2031 | logit("channel %d: bad ext data", c->self); |
7e7327a1 | 2032 | return; |
2033 | } | |
2034 | data = packet_get_string(&data_len); | |
95500969 | 2035 | packet_check_eom(); |
7e7327a1 | 2036 | if (data_len > c->local_window) { |
bbe88b6d | 2037 | logit("channel %d: rcvd too much extended_data %d, win %d", |
7e7327a1 | 2038 | c->self, data_len, c->local_window); |
2039 | xfree(data); | |
2040 | return; | |
2041 | } | |
de273eef | 2042 | debug2("channel %d: rcvd ext data %d", c->self, data_len); |
7e7327a1 | 2043 | c->local_window -= data_len; |
2044 | buffer_append(&c->extended, data, data_len); | |
2045 | xfree(data); | |
2046 | } | |
2047 | ||
6ae2364d | 2048 | void |
7819b5c3 | 2049 | channel_input_ieof(int type, u_int32_t seq, void *ctxt) |
7368a6c8 | 2050 | { |
2051 | int id; | |
2052 | Channel *c; | |
2053 | ||
7368a6c8 | 2054 | id = packet_get_int(); |
95500969 | 2055 | packet_check_eom(); |
7368a6c8 | 2056 | c = channel_lookup(id); |
2057 | if (c == NULL) | |
2058 | packet_disconnect("Received ieof for nonexistent channel %d.", id); | |
2059 | chan_rcvd_ieof(c); | |
a5f82435 | 2060 | |
2061 | /* XXX force input close */ | |
8341f420 | 2062 | if (c->force_drain && c->istate == CHAN_INPUT_OPEN) { |
a5f82435 | 2063 | debug("channel %d: FORCE input drain", c->self); |
2064 | c->istate = CHAN_INPUT_WAIT_DRAIN; | |
32e7d71f | 2065 | if (buffer_len(&c->input) == 0) |
2066 | chan_ibuf_empty(c); | |
a5f82435 | 2067 | } |
2068 | ||
7368a6c8 | 2069 | } |
8efc0c15 | 2070 | |
6ae2364d | 2071 | void |
7819b5c3 | 2072 | channel_input_close(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 2073 | { |
7368a6c8 | 2074 | int id; |
2075 | Channel *c; | |
5260325f | 2076 | |
7368a6c8 | 2077 | id = packet_get_int(); |
95500969 | 2078 | packet_check_eom(); |
7368a6c8 | 2079 | c = channel_lookup(id); |
2080 | if (c == NULL) | |
2081 | packet_disconnect("Received close for nonexistent channel %d.", id); | |
aa3378df | 2082 | |
2083 | /* | |
2084 | * Send a confirmation that we have closed the channel and no more | |
2085 | * data is coming for it. | |
2086 | */ | |
5260325f | 2087 | packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION); |
7368a6c8 | 2088 | packet_put_int(c->remote_id); |
5260325f | 2089 | packet_send(); |
2090 | ||
aa3378df | 2091 | /* |
2092 | * If the channel is in closed state, we have sent a close request, | |
2093 | * and the other side will eventually respond with a confirmation. | |
2094 | * Thus, we cannot free the channel here, because then there would be | |
2095 | * no-one to receive the confirmation. The channel gets freed when | |
2096 | * the confirmation arrives. | |
2097 | */ | |
7368a6c8 | 2098 | if (c->type != SSH_CHANNEL_CLOSED) { |
aa3378df | 2099 | /* |
2100 | * Not a closed channel - mark it as draining, which will | |
2101 | * cause it to be freed later. | |
2102 | */ | |
9c50edcf | 2103 | buffer_clear(&c->input); |
7368a6c8 | 2104 | c->type = SSH_CHANNEL_OUTPUT_DRAINING; |
5260325f | 2105 | } |
8efc0c15 | 2106 | } |
2107 | ||
7368a6c8 | 2108 | /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */ |
6ae2364d | 2109 | void |
7819b5c3 | 2110 | channel_input_oclose(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 2111 | { |
7368a6c8 | 2112 | int id = packet_get_int(); |
2113 | Channel *c = channel_lookup(id); | |
a8a21a53 | 2114 | |
95500969 | 2115 | packet_check_eom(); |
7368a6c8 | 2116 | if (c == NULL) |
2117 | packet_disconnect("Received oclose for nonexistent channel %d.", id); | |
2118 | chan_rcvd_oclose(c); | |
8efc0c15 | 2119 | } |
2120 | ||
6ae2364d | 2121 | void |
7819b5c3 | 2122 | channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt) |
7368a6c8 | 2123 | { |
2124 | int id = packet_get_int(); | |
2125 | Channel *c = channel_lookup(id); | |
2126 | ||
95500969 | 2127 | packet_check_eom(); |
7368a6c8 | 2128 | if (c == NULL) |
2129 | packet_disconnect("Received close confirmation for " | |
2130 | "out-of-range channel %d.", id); | |
2131 | if (c->type != SSH_CHANNEL_CLOSED) | |
2132 | packet_disconnect("Received close confirmation for " | |
2133 | "non-closed channel %d (type %d).", id, c->type); | |
719fc62f | 2134 | channel_free(c); |
7368a6c8 | 2135 | } |
8efc0c15 | 2136 | |
6ae2364d | 2137 | void |
7819b5c3 | 2138 | channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 2139 | { |
7368a6c8 | 2140 | int id, remote_id; |
2141 | Channel *c; | |
5260325f | 2142 | |
7368a6c8 | 2143 | id = packet_get_int(); |
2144 | c = channel_lookup(id); | |
5260325f | 2145 | |
7368a6c8 | 2146 | if (c==NULL || c->type != SSH_CHANNEL_OPENING) |
2147 | packet_disconnect("Received open confirmation for " | |
2148 | "non-opening channel %d.", id); | |
2149 | remote_id = packet_get_int(); | |
aa3378df | 2150 | /* Record the remote channel number and mark that the channel is now open. */ |
7368a6c8 | 2151 | c->remote_id = remote_id; |
2152 | c->type = SSH_CHANNEL_OPEN; | |
7e7327a1 | 2153 | |
2154 | if (compat20) { | |
2155 | c->remote_window = packet_get_int(); | |
2156 | c->remote_maxpacket = packet_get_int(); | |
05ca0898 | 2157 | if (c->confirm) { |
de273eef | 2158 | debug2("callback start"); |
5e96b616 | 2159 | c->confirm(c->self, c->confirm_ctx); |
de273eef | 2160 | debug2("callback done"); |
7e7327a1 | 2161 | } |
d7ac5f18 | 2162 | debug2("channel %d: open confirm rwindow %u rmax %u", c->self, |
7e7327a1 | 2163 | c->remote_window, c->remote_maxpacket); |
2164 | } | |
95500969 | 2165 | packet_check_eom(); |
8efc0c15 | 2166 | } |
2167 | ||
396c147e | 2168 | static char * |
d18e0850 | 2169 | reason2txt(int reason) |
2170 | { | |
6aacefa7 | 2171 | switch (reason) { |
d18e0850 | 2172 | case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED: |
2173 | return "administratively prohibited"; | |
2174 | case SSH2_OPEN_CONNECT_FAILED: | |
2175 | return "connect failed"; | |
2176 | case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE: | |
2177 | return "unknown channel type"; | |
2178 | case SSH2_OPEN_RESOURCE_SHORTAGE: | |
2179 | return "resource shortage"; | |
2180 | } | |
7e8c18e9 | 2181 | return "unknown reason"; |
d18e0850 | 2182 | } |
2183 | ||
6ae2364d | 2184 | void |
7819b5c3 | 2185 | channel_input_open_failure(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 2186 | { |
02a024dd | 2187 | int id, reason; |
2188 | char *msg = NULL, *lang = NULL; | |
7368a6c8 | 2189 | Channel *c; |
5260325f | 2190 | |
7368a6c8 | 2191 | id = packet_get_int(); |
2192 | c = channel_lookup(id); | |
2193 | ||
2194 | if (c==NULL || c->type != SSH_CHANNEL_OPENING) | |
2195 | packet_disconnect("Received open failure for " | |
2196 | "non-opening channel %d.", id); | |
7e7327a1 | 2197 | if (compat20) { |
02a024dd | 2198 | reason = packet_get_int(); |
fbe90f7b | 2199 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { |
02a024dd | 2200 | msg = packet_get_string(NULL); |
2201 | lang = packet_get_string(NULL); | |
2202 | } | |
bbe88b6d | 2203 | logit("channel %d: open failed: %s%s%s", id, |
d18e0850 | 2204 | reason2txt(reason), msg ? ": ": "", msg ? msg : ""); |
02a024dd | 2205 | if (msg != NULL) |
2206 | xfree(msg); | |
2207 | if (lang != NULL) | |
2208 | xfree(lang); | |
7e7327a1 | 2209 | } |
95500969 | 2210 | packet_check_eom(); |
5260325f | 2211 | /* Free the channel. This will also close the socket. */ |
719fc62f | 2212 | channel_free(c); |
8efc0c15 | 2213 | } |
2214 | ||
8e7895b8 | 2215 | void |
7819b5c3 | 2216 | channel_input_window_adjust(int type, u_int32_t seq, void *ctxt) |
8e7895b8 | 2217 | { |
2218 | Channel *c; | |
f91d9a89 | 2219 | int id; |
2220 | u_int adjust; | |
3ffc6336 | 2221 | |
8e7895b8 | 2222 | if (!compat20) |
2223 | return; | |
8efc0c15 | 2224 | |
8e7895b8 | 2225 | /* Get the channel number and verify it. */ |
2226 | id = packet_get_int(); | |
2227 | c = channel_lookup(id); | |
2228 | ||
b872f7f0 | 2229 | if (c == NULL) { |
2230 | logit("Received window adjust for non-open channel %d.", id); | |
8e7895b8 | 2231 | return; |
2232 | } | |
2233 | adjust = packet_get_int(); | |
95500969 | 2234 | packet_check_eom(); |
f91d9a89 | 2235 | debug2("channel %d: rcvd adjust %u", id, adjust); |
8e7895b8 | 2236 | c->remote_window += adjust; |
2237 | } | |
2238 | ||
2239 | void | |
7819b5c3 | 2240 | channel_input_port_open(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 2241 | { |
8e7895b8 | 2242 | Channel *c = NULL; |
2243 | u_short host_port; | |
2244 | char *host, *originator_string; | |
2245 | int remote_id, sock = -1; | |
5260325f | 2246 | |
8e7895b8 | 2247 | remote_id = packet_get_int(); |
2248 | host = packet_get_string(NULL); | |
2249 | host_port = packet_get_int(); | |
2250 | ||
2251 | if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) { | |
2252 | originator_string = packet_get_string(NULL); | |
2253 | } else { | |
2254 | originator_string = xstrdup("unknown (remote did not supply name)"); | |
2255 | } | |
95500969 | 2256 | packet_check_eom(); |
8e7895b8 | 2257 | sock = channel_connect_to(host, host_port); |
2258 | if (sock != -1) { | |
2259 | c = channel_new("connected socket", | |
2260 | SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0, | |
2261 | originator_string, 1); | |
3a0d3d54 | 2262 | c->remote_id = remote_id; |
5260325f | 2263 | } |
0d942eff | 2264 | xfree(originator_string); |
8e7895b8 | 2265 | if (c == NULL) { |
2266 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
2267 | packet_put_int(remote_id); | |
2268 | packet_send(); | |
2269 | } | |
2270 | xfree(host); | |
8efc0c15 | 2271 | } |
2272 | ||
8e7895b8 | 2273 | |
2274 | /* -- tcp forwarding */ | |
2275 | ||
5e4a7219 | 2276 | void |
2277 | channel_set_af(int af) | |
2278 | { | |
2279 | IPv4or6 = af; | |
2280 | } | |
2281 | ||
5641aefa | 2282 | static int |
2283 | channel_setup_fwd_listener(int type, const char *listen_addr, u_short listen_port, | |
2284 | const char *host_to_connect, u_short port_to_connect, int gateway_ports) | |
8efc0c15 | 2285 | { |
719fc62f | 2286 | Channel *c; |
442aee3a | 2287 | int sock, r, success = 0, wildcard = 0, is_client; |
48e671d5 | 2288 | struct addrinfo hints, *ai, *aitop; |
3867aa0a | 2289 | const char *host, *addr; |
5641aefa | 2290 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; |
5260325f | 2291 | |
5641aefa | 2292 | host = (type == SSH_CHANNEL_RPORT_LISTENER) ? |
2293 | listen_addr : host_to_connect; | |
3867aa0a | 2294 | is_client = (type == SSH_CHANNEL_PORT_LISTENER); |
02a024dd | 2295 | |
5641aefa | 2296 | if (host == NULL) { |
2297 | error("No forward host name."); | |
38946c65 | 2298 | return 0; |
fa08c86b | 2299 | } |
719fc62f | 2300 | if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) { |
02a024dd | 2301 | error("Forward host name too long."); |
38946c65 | 2302 | return 0; |
02a024dd | 2303 | } |
5260325f | 2304 | |
3867aa0a | 2305 | /* |
2306 | * Determine whether or not a port forward listens to loopback, | |
f8cc7664 | 2307 | * specified address or wildcard. On the client, a specified bind |
2308 | * address will always override gateway_ports. On the server, a | |
2309 | * gateway_ports of 1 (``yes'') will override the client's | |
2310 | * specification and force a wildcard bind, whereas a value of 2 | |
2311 | * (``clientspecified'') will bind to whatever address the client | |
3867aa0a | 2312 | * asked for. |
2313 | * | |
2314 | * Special-case listen_addrs are: | |
2315 | * | |
2316 | * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR | |
2317 | * "" (empty string), "*" -> wildcard v4/v6 | |
2318 | * "localhost" -> loopback v4/v6 | |
2319 | */ | |
2320 | addr = NULL; | |
2321 | if (listen_addr == NULL) { | |
2322 | /* No address specified: default to gateway_ports setting */ | |
2323 | if (gateway_ports) | |
2324 | wildcard = 1; | |
2325 | } else if (gateway_ports || is_client) { | |
2326 | if (((datafellows & SSH_OLD_FORWARD_ADDR) && | |
2327 | strcmp(listen_addr, "0.0.0.0") == 0) || | |
2328 | *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 || | |
2329 | (!is_client && gateway_ports == 1)) | |
2330 | wildcard = 1; | |
2331 | else if (strcmp(listen_addr, "localhost") != 0) | |
2332 | addr = listen_addr; | |
2333 | } | |
2334 | ||
2335 | debug3("channel_setup_fwd_listener: type %d wildcard %d addr %s", | |
2336 | type, wildcard, (addr == NULL) ? "NULL" : addr); | |
2337 | ||
aa3378df | 2338 | /* |
48e671d5 | 2339 | * getaddrinfo returns a loopback address if the hostname is |
2340 | * set to NULL and hints.ai_flags is not AI_PASSIVE | |
aa3378df | 2341 | */ |
48e671d5 | 2342 | memset(&hints, 0, sizeof(hints)); |
2343 | hints.ai_family = IPv4or6; | |
3867aa0a | 2344 | hints.ai_flags = wildcard ? AI_PASSIVE : 0; |
48e671d5 | 2345 | hints.ai_socktype = SOCK_STREAM; |
fa08c86b | 2346 | snprintf(strport, sizeof strport, "%d", listen_port); |
3867aa0a | 2347 | if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) { |
2348 | if (addr == NULL) { | |
2349 | /* This really shouldn't happen */ | |
2350 | packet_disconnect("getaddrinfo: fatal error: %s", | |
2351 | gai_strerror(r)); | |
2352 | } else { | |
38946c65 | 2353 | error("channel_setup_fwd_listener: " |
3867aa0a | 2354 | "getaddrinfo(%.64s): %s", addr, gai_strerror(r)); |
2355 | } | |
38946c65 | 2356 | return 0; |
3867aa0a | 2357 | } |
48e671d5 | 2358 | |
48e671d5 | 2359 | for (ai = aitop; ai; ai = ai->ai_next) { |
2360 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2361 | continue; | |
2362 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), | |
2363 | strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
5641aefa | 2364 | error("channel_setup_fwd_listener: getnameinfo failed"); |
48e671d5 | 2365 | continue; |
2366 | } | |
2367 | /* Create a port to listen for the host. */ | |
3e131a6d | 2368 | sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); |
48e671d5 | 2369 | if (sock < 0) { |
2370 | /* this is no error since kernel may not support ipv6 */ | |
2371 | verbose("socket: %.100s", strerror(errno)); | |
2372 | continue; | |
2373 | } | |
442aee3a | 2374 | |
2375 | channel_set_reuseaddr(sock); | |
facfd613 | 2376 | |
48e671d5 | 2377 | debug("Local forwarding listening on %s port %s.", ntop, strport); |
2378 | ||
2379 | /* Bind the socket to the address. */ | |
2380 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
2381 | /* address can be in use ipv6 address is already bound */ | |
16218745 | 2382 | if (!ai->ai_next) |
2383 | error("bind: %.100s", strerror(errno)); | |
2384 | else | |
2385 | verbose("bind: %.100s", strerror(errno)); | |
2b87da3b | 2386 | |
48e671d5 | 2387 | close(sock); |
2388 | continue; | |
2389 | } | |
2390 | /* Start listening for connections on the socket. */ | |
fce39749 | 2391 | if (listen(sock, SSH_LISTEN_BACKLOG) < 0) { |
48e671d5 | 2392 | error("listen: %.100s", strerror(errno)); |
2393 | close(sock); | |
2394 | continue; | |
2395 | } | |
2396 | /* Allocate a channel number for the socket. */ | |
8e7895b8 | 2397 | c = channel_new("port listener", type, sock, sock, -1, |
0b242b12 | 2398 | CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, |
0d942eff | 2399 | 0, "port listener", 1); |
719fc62f | 2400 | strlcpy(c->path, host, sizeof(c->path)); |
2401 | c->host_port = port_to_connect; | |
2402 | c->listening_port = listen_port; | |
48e671d5 | 2403 | success = 1; |
2404 | } | |
2405 | if (success == 0) | |
5641aefa | 2406 | error("channel_setup_fwd_listener: cannot listen to port: %d", |
02a024dd | 2407 | listen_port); |
48e671d5 | 2408 | freeaddrinfo(aitop); |
02a024dd | 2409 | return success; |
5260325f | 2410 | } |
8efc0c15 | 2411 | |
d740ec16 | 2412 | int |
2413 | channel_cancel_rport_listener(const char *host, u_short port) | |
2414 | { | |
9a995072 | 2415 | u_int i; |
2416 | int found = 0; | |
d740ec16 | 2417 | |
f8cc7664 | 2418 | for (i = 0; i < channels_alloc; i++) { |
d740ec16 | 2419 | Channel *c = channels[i]; |
2420 | ||
2421 | if (c != NULL && c->type == SSH_CHANNEL_RPORT_LISTENER && | |
2422 | strncmp(c->path, host, sizeof(c->path)) == 0 && | |
f2107e97 | 2423 | c->listening_port == port) { |
2912cbd6 | 2424 | debug2("%s: close channel %d", __func__, i); |
d740ec16 | 2425 | channel_free(c); |
2426 | found = 1; | |
2427 | } | |
2428 | } | |
2429 | ||
2430 | return (found); | |
2431 | } | |
2432 | ||
5641aefa | 2433 | /* protocol local port fwd, used by ssh (and sshd in v1) */ |
2434 | int | |
3867aa0a | 2435 | channel_setup_local_fwd_listener(const char *listen_host, u_short listen_port, |
5641aefa | 2436 | const char *host_to_connect, u_short port_to_connect, int gateway_ports) |
2437 | { | |
2438 | return channel_setup_fwd_listener(SSH_CHANNEL_PORT_LISTENER, | |
3867aa0a | 2439 | listen_host, listen_port, host_to_connect, port_to_connect, |
2440 | gateway_ports); | |
5641aefa | 2441 | } |
2442 | ||
2443 | /* protocol v2 remote port fwd, used by sshd */ | |
2444 | int | |
2445 | channel_setup_remote_fwd_listener(const char *listen_address, | |
2446 | u_short listen_port, int gateway_ports) | |
2447 | { | |
2448 | return channel_setup_fwd_listener(SSH_CHANNEL_RPORT_LISTENER, | |
2449 | listen_address, listen_port, NULL, 0, gateway_ports); | |
2450 | } | |
2451 | ||
aa3378df | 2452 | /* |
2453 | * Initiate forwarding of connections to port "port" on remote host through | |
2454 | * the secure channel to host:port from local side. | |
2455 | */ | |
8efc0c15 | 2456 | |
6ae2364d | 2457 | void |
3867aa0a | 2458 | channel_request_remote_forwarding(const char *listen_host, u_short listen_port, |
fa08c86b | 2459 | const char *host_to_connect, u_short port_to_connect) |
8efc0c15 | 2460 | { |
54a5250f | 2461 | int type, success = 0; |
fa08c86b | 2462 | |
5260325f | 2463 | /* Record locally that connection to this host/port is permitted. */ |
2464 | if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION) | |
2465 | fatal("channel_request_remote_forwarding: too many forwards"); | |
2466 | ||
5260325f | 2467 | /* Send the forward request to the remote side. */ |
7e7327a1 | 2468 | if (compat20) { |
3867aa0a | 2469 | const char *address_to_bind; |
2470 | if (listen_host == NULL) | |
2471 | address_to_bind = "localhost"; | |
2472 | else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) | |
2473 | address_to_bind = ""; | |
2474 | else | |
2475 | address_to_bind = listen_host; | |
2476 | ||
7e7327a1 | 2477 | packet_start(SSH2_MSG_GLOBAL_REQUEST); |
2478 | packet_put_cstring("tcpip-forward"); | |
e0ae8728 | 2479 | packet_put_char(1); /* boolean: want reply */ |
7e7327a1 | 2480 | packet_put_cstring(address_to_bind); |
2481 | packet_put_int(listen_port); | |
fa08c86b | 2482 | packet_send(); |
2483 | packet_write_wait(); | |
2484 | /* Assume that server accepts the request */ | |
2485 | success = 1; | |
7e7327a1 | 2486 | } else { |
2487 | packet_start(SSH_CMSG_PORT_FORWARD_REQUEST); | |
7e7327a1 | 2488 | packet_put_int(listen_port); |
d6f24e45 | 2489 | packet_put_cstring(host_to_connect); |
2490 | packet_put_int(port_to_connect); | |
7e7327a1 | 2491 | packet_send(); |
2492 | packet_write_wait(); | |
fa08c86b | 2493 | |
2494 | /* Wait for response from the remote side. */ | |
54a5250f | 2495 | type = packet_read(); |
fa08c86b | 2496 | switch (type) { |
2497 | case SSH_SMSG_SUCCESS: | |
2498 | success = 1; | |
2499 | break; | |
2500 | case SSH_SMSG_FAILURE: | |
bbe88b6d | 2501 | logit("Warning: Server denied remote port forwarding."); |
fa08c86b | 2502 | break; |
2503 | default: | |
2504 | /* Unknown packet */ | |
2505 | packet_disconnect("Protocol error for port forward request:" | |
2506 | "received packet type %d.", type); | |
2507 | } | |
2508 | } | |
2509 | if (success) { | |
2510 | permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect); | |
2511 | permitted_opens[num_permitted_opens].port_to_connect = port_to_connect; | |
2512 | permitted_opens[num_permitted_opens].listen_port = listen_port; | |
2513 | num_permitted_opens++; | |
7e7327a1 | 2514 | } |
8efc0c15 | 2515 | } |
2516 | ||
d740ec16 | 2517 | /* |
f2107e97 | 2518 | * Request cancellation of remote forwarding of connection host:port from |
d740ec16 | 2519 | * local side. |
2520 | */ | |
d740ec16 | 2521 | void |
3867aa0a | 2522 | channel_request_rforward_cancel(const char *host, u_short port) |
d740ec16 | 2523 | { |
2524 | int i; | |
d740ec16 | 2525 | |
2526 | if (!compat20) | |
2527 | return; | |
2528 | ||
2529 | for (i = 0; i < num_permitted_opens; i++) { | |
f2107e97 | 2530 | if (permitted_opens[i].host_to_connect != NULL && |
d740ec16 | 2531 | permitted_opens[i].listen_port == port) |
2532 | break; | |
2533 | } | |
2534 | if (i >= num_permitted_opens) { | |
2535 | debug("%s: requested forward not found", __func__); | |
2536 | return; | |
2537 | } | |
2538 | packet_start(SSH2_MSG_GLOBAL_REQUEST); | |
2539 | packet_put_cstring("cancel-tcpip-forward"); | |
2540 | packet_put_char(0); | |
3867aa0a | 2541 | packet_put_cstring(host == NULL ? "" : host); |
d740ec16 | 2542 | packet_put_int(port); |
2543 | packet_send(); | |
2544 | ||
2545 | permitted_opens[i].listen_port = 0; | |
2546 | permitted_opens[i].port_to_connect = 0; | |
8c4bd764 | 2547 | xfree(permitted_opens[i].host_to_connect); |
d740ec16 | 2548 | permitted_opens[i].host_to_connect = NULL; |
2549 | } | |
2550 | ||
aa3378df | 2551 | /* |
2552 | * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates | |
2553 | * listening for the port, and sends back a success reply (or disconnect | |
2554 | * message if there was an error). This never returns if there was an error. | |
2555 | */ | |
8efc0c15 | 2556 | |
6ae2364d | 2557 | void |
1d1ffb87 | 2558 | channel_input_port_forward_request(int is_root, int gateway_ports) |
8efc0c15 | 2559 | { |
57112b5a | 2560 | u_short port, host_port; |
5260325f | 2561 | char *hostname; |
2562 | ||
2563 | /* Get arguments from the packet. */ | |
2564 | port = packet_get_int(); | |
2565 | hostname = packet_get_string(NULL); | |
2566 | host_port = packet_get_int(); | |
2567 | ||
3c62e7eb | 2568 | #ifndef HAVE_CYGWIN |
aa3378df | 2569 | /* |
2570 | * Check that an unprivileged user is not trying to forward a | |
2571 | * privileged port. | |
2572 | */ | |
5260325f | 2573 | if (port < IPPORT_RESERVED && !is_root) |
8e7c9afc | 2574 | packet_disconnect( |
2575 | "Requested forwarding of port %d but user is not root.", | |
2576 | port); | |
2577 | if (host_port == 0) | |
2578 | packet_disconnect("Dynamic forwarding denied."); | |
3c62e7eb | 2579 | #endif |
8e7c9afc | 2580 | |
fa08c86b | 2581 | /* Initiate forwarding */ |
3867aa0a | 2582 | channel_setup_local_fwd_listener(NULL, port, hostname, |
2583 | host_port, gateway_ports); | |
5260325f | 2584 | |
2585 | /* Free the argument string. */ | |
2586 | xfree(hostname); | |
8efc0c15 | 2587 | } |
2588 | ||
01794848 | 2589 | /* |
2590 | * Permits opening to any host/port if permitted_opens[] is empty. This is | |
2591 | * usually called by the server, because the user could connect to any port | |
2592 | * anyway, and the server has no way to know but to trust the client anyway. | |
2593 | */ | |
2594 | void | |
d5bb9418 | 2595 | channel_permit_all_opens(void) |
01794848 | 2596 | { |
2597 | if (num_permitted_opens == 0) | |
2598 | all_opens_permitted = 1; | |
2599 | } | |
2600 | ||
cd332296 | 2601 | void |
01794848 | 2602 | channel_add_permitted_opens(char *host, int port) |
2603 | { | |
2604 | if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION) | |
2605 | fatal("channel_request_remote_forwarding: too many forwards"); | |
2606 | debug("allow port forwarding to host %s port %d", host, port); | |
2607 | ||
2608 | permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host); | |
2609 | permitted_opens[num_permitted_opens].port_to_connect = port; | |
2610 | num_permitted_opens++; | |
2611 | ||
2612 | all_opens_permitted = 0; | |
2613 | } | |
2614 | ||
cd332296 | 2615 | void |
01794848 | 2616 | channel_clear_permitted_opens(void) |
2617 | { | |
2618 | int i; | |
2619 | ||
2620 | for (i = 0; i < num_permitted_opens; i++) | |
d740ec16 | 2621 | if (permitted_opens[i].host_to_connect != NULL) |
2622 | xfree(permitted_opens[i].host_to_connect); | |
01794848 | 2623 | num_permitted_opens = 0; |
2624 | ||
2625 | } | |
2626 | ||
2627 | ||
2628 | /* return socket to remote host, port */ | |
396c147e | 2629 | static int |
01794848 | 2630 | connect_to(const char *host, u_short port) |
8efc0c15 | 2631 | { |
48e671d5 | 2632 | struct addrinfo hints, *ai, *aitop; |
2633 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; | |
2634 | int gaierr; | |
7368a6c8 | 2635 | int sock = -1; |
48e671d5 | 2636 | |
2637 | memset(&hints, 0, sizeof(hints)); | |
2638 | hints.ai_family = IPv4or6; | |
2639 | hints.ai_socktype = SOCK_STREAM; | |
01794848 | 2640 | snprintf(strport, sizeof strport, "%d", port); |
48e671d5 | 2641 | if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) { |
01794848 | 2642 | error("connect_to %.100s: unknown host (%s)", host, |
2643 | gai_strerror(gaierr)); | |
7368a6c8 | 2644 | return -1; |
48e671d5 | 2645 | } |
48e671d5 | 2646 | for (ai = aitop; ai; ai = ai->ai_next) { |
2647 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2648 | continue; | |
2649 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), | |
2650 | strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
01794848 | 2651 | error("connect_to: getnameinfo failed"); |
48e671d5 | 2652 | continue; |
5260325f | 2653 | } |
3e131a6d | 2654 | sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); |
48e671d5 | 2655 | if (sock < 0) { |
4940c411 | 2656 | if (ai->ai_next == NULL) |
2657 | error("socket: %.100s", strerror(errno)); | |
2658 | else | |
2659 | verbose("socket: %.100s", strerror(errno)); | |
48e671d5 | 2660 | continue; |
5260325f | 2661 | } |
170694d7 | 2662 | if (set_nonblock(sock) == -1) |
2663 | fatal("%s: set_nonblock(%d)", __func__, sock); | |
97fb6912 | 2664 | if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 && |
2665 | errno != EINPROGRESS) { | |
01794848 | 2666 | error("connect_to %.100s port %s: %.100s", ntop, strport, |
48e671d5 | 2667 | strerror(errno)); |
2668 | close(sock); | |
2b87da3b | 2669 | continue; /* fail -- try next */ |
48e671d5 | 2670 | } |
2671 | break; /* success */ | |
5260325f | 2672 | |
5260325f | 2673 | } |
48e671d5 | 2674 | freeaddrinfo(aitop); |
48e671d5 | 2675 | if (!ai) { |
01794848 | 2676 | error("connect_to %.100s port %d: failed.", host, port); |
7368a6c8 | 2677 | return -1; |
8efc0c15 | 2678 | } |
7368a6c8 | 2679 | /* success */ |
811a6342 | 2680 | set_nodelay(sock); |
7368a6c8 | 2681 | return sock; |
2682 | } | |
01794848 | 2683 | |
fa08c86b | 2684 | int |
b3f8a79c | 2685 | channel_connect_by_listen_address(u_short listen_port) |
fa08c86b | 2686 | { |
2687 | int i; | |
01794848 | 2688 | |
fa08c86b | 2689 | for (i = 0; i < num_permitted_opens; i++) |
d740ec16 | 2690 | if (permitted_opens[i].host_to_connect != NULL && |
2691 | permitted_opens[i].listen_port == listen_port) | |
01794848 | 2692 | return connect_to( |
fa08c86b | 2693 | permitted_opens[i].host_to_connect, |
2694 | permitted_opens[i].port_to_connect); | |
0b6fbf03 | 2695 | error("WARNING: Server requests forwarding for unknown listen_port %d", |
2696 | listen_port); | |
fa08c86b | 2697 | return -1; |
2698 | } | |
48e671d5 | 2699 | |
01794848 | 2700 | /* Check if connecting to that port is permitted and connect. */ |
2701 | int | |
2702 | channel_connect_to(const char *host, u_short port) | |
2703 | { | |
2704 | int i, permit; | |
2705 | ||
2706 | permit = all_opens_permitted; | |
2707 | if (!permit) { | |
2708 | for (i = 0; i < num_permitted_opens; i++) | |
d740ec16 | 2709 | if (permitted_opens[i].host_to_connect != NULL && |
2710 | permitted_opens[i].port_to_connect == port && | |
01794848 | 2711 | strcmp(permitted_opens[i].host_to_connect, host) == 0) |
2712 | permit = 1; | |
2713 | ||
2714 | } | |
2715 | if (!permit) { | |
bbe88b6d | 2716 | logit("Received request to connect to host %.100s port %d, " |
01794848 | 2717 | "but the request was denied.", host, port); |
2718 | return -1; | |
2719 | } | |
2720 | return connect_to(host, port); | |
2721 | } | |
2722 | ||
5e96b616 | 2723 | void |
2724 | channel_send_window_changes(void) | |
2725 | { | |
9a995072 | 2726 | u_int i; |
5e96b616 | 2727 | struct winsize ws; |
2728 | ||
2729 | for (i = 0; i < channels_alloc; i++) { | |
f8cc7664 | 2730 | if (channels[i] == NULL || !channels[i]->client_tty || |
5e96b616 | 2731 | channels[i]->type != SSH_CHANNEL_OPEN) |
2732 | continue; | |
2733 | if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0) | |
2734 | continue; | |
2735 | channel_request_start(i, "window-change", 0); | |
2736 | packet_put_int(ws.ws_col); | |
2737 | packet_put_int(ws.ws_row); | |
2738 | packet_put_int(ws.ws_xpixel); | |
2739 | packet_put_int(ws.ws_ypixel); | |
2740 | packet_send(); | |
2741 | } | |
2742 | } | |
2743 | ||
8e7895b8 | 2744 | /* -- X11 forwarding */ |
8efc0c15 | 2745 | |
aa3378df | 2746 | /* |
2747 | * Creates an internet domain socket for listening for X11 connections. | |
57f228e8 | 2748 | * Returns 0 and a suitable display number for the DISPLAY variable |
2749 | * stored in display_numberp , or -1 if an error occurs. | |
aa3378df | 2750 | */ |
c9d0ad9b | 2751 | int |
e6e573bd | 2752 | x11_create_display_inet(int x11_display_offset, int x11_use_localhost, |
d08341e6 | 2753 | int single_connection, u_int *display_numberp, int **chanids) |
8efc0c15 | 2754 | { |
ac151b18 | 2755 | Channel *nc = NULL; |
57112b5a | 2756 | int display_number, sock; |
2757 | u_short port; | |
48e671d5 | 2758 | struct addrinfo hints, *ai, *aitop; |
2759 | char strport[NI_MAXSERV]; | |
2760 | int gaierr, n, num_socks = 0, socks[NUM_SOCKS]; | |
5260325f | 2761 | |
59e5aff5 | 2762 | if (chanids == NULL) |
2763 | return -1; | |
2764 | ||
95f1eccc | 2765 | for (display_number = x11_display_offset; |
184eed6a | 2766 | display_number < MAX_DISPLAYS; |
2767 | display_number++) { | |
5260325f | 2768 | port = 6000 + display_number; |
48e671d5 | 2769 | memset(&hints, 0, sizeof(hints)); |
2770 | hints.ai_family = IPv4or6; | |
e6e573bd | 2771 | hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE; |
48e671d5 | 2772 | hints.ai_socktype = SOCK_STREAM; |
2773 | snprintf(strport, sizeof strport, "%d", port); | |
2774 | if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) { | |
2775 | error("getaddrinfo: %.100s", gai_strerror(gaierr)); | |
c9d0ad9b | 2776 | return -1; |
5260325f | 2777 | } |
48e671d5 | 2778 | for (ai = aitop; ai; ai = ai->ai_next) { |
2779 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2780 | continue; | |
3e131a6d | 2781 | sock = socket(ai->ai_family, ai->ai_socktype, |
2782 | ai->ai_protocol); | |
48e671d5 | 2783 | if (sock < 0) { |
4ee81249 | 2784 | if ((errno != EINVAL) && (errno != EAFNOSUPPORT)) { |
80a44451 | 2785 | error("socket: %.100s", strerror(errno)); |
0ea89f7e | 2786 | freeaddrinfo(aitop); |
c9d0ad9b | 2787 | return -1; |
80a44451 | 2788 | } else { |
22d89d24 | 2789 | debug("x11_create_display_inet: Socket family %d not supported", |
2790 | ai->ai_family); | |
80a44451 | 2791 | continue; |
2792 | } | |
48e671d5 | 2793 | } |
688aaeda | 2794 | #ifdef IPV6_V6ONLY |
2795 | if (ai->ai_family == AF_INET6) { | |
2796 | int on = 1; | |
2797 | if (setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) < 0) | |
2798 | error("setsockopt IPV6_V6ONLY: %.100s", strerror(errno)); | |
2799 | } | |
2800 | #endif | |
442aee3a | 2801 | channel_set_reuseaddr(sock); |
48e671d5 | 2802 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { |
d7ac5f18 | 2803 | debug2("bind port %d: %.100s", port, strerror(errno)); |
48e671d5 | 2804 | close(sock); |
16218745 | 2805 | |
2806 | if (ai->ai_next) | |
2807 | continue; | |
2808 | ||
48e671d5 | 2809 | for (n = 0; n < num_socks; n++) { |
48e671d5 | 2810 | close(socks[n]); |
2811 | } | |
2812 | num_socks = 0; | |
2813 | break; | |
2814 | } | |
2815 | socks[num_socks++] = sock; | |
80faa19f | 2816 | #ifndef DONT_TRY_OTHER_AF |
48e671d5 | 2817 | if (num_socks == NUM_SOCKS) |
2818 | break; | |
80faa19f | 2819 | #else |
688aaeda | 2820 | if (x11_use_localhost) { |
2821 | if (num_socks == NUM_SOCKS) | |
2822 | break; | |
2823 | } else { | |
2824 | break; | |
2825 | } | |
80faa19f | 2826 | #endif |
5260325f | 2827 | } |
4ccb01d6 | 2828 | freeaddrinfo(aitop); |
48e671d5 | 2829 | if (num_socks > 0) |
2830 | break; | |
5260325f | 2831 | } |
2832 | if (display_number >= MAX_DISPLAYS) { | |
2833 | error("Failed to allocate internet-domain X11 display socket."); | |
c9d0ad9b | 2834 | return -1; |
8efc0c15 | 2835 | } |
5260325f | 2836 | /* Start listening for connections on the socket. */ |
48e671d5 | 2837 | for (n = 0; n < num_socks; n++) { |
2838 | sock = socks[n]; | |
fce39749 | 2839 | if (listen(sock, SSH_LISTEN_BACKLOG) < 0) { |
48e671d5 | 2840 | error("listen: %.100s", strerror(errno)); |
48e671d5 | 2841 | close(sock); |
c9d0ad9b | 2842 | return -1; |
a7effaac | 2843 | } |
a7effaac | 2844 | } |
5260325f | 2845 | |
48e671d5 | 2846 | /* Allocate a channel for each socket. */ |
59e5aff5 | 2847 | *chanids = xmalloc(sizeof(**chanids) * (num_socks + 1)); |
48e671d5 | 2848 | for (n = 0; n < num_socks; n++) { |
2849 | sock = socks[n]; | |
ac151b18 | 2850 | nc = channel_new("x11 listener", |
0b242b12 | 2851 | SSH_CHANNEL_X11_LISTENER, sock, sock, -1, |
2852 | CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, | |
0d942eff | 2853 | 0, "X11 inet listener", 1); |
3a0d3d54 | 2854 | nc->single_connection = single_connection; |
59e5aff5 | 2855 | (*chanids)[n] = nc->self; |
48e671d5 | 2856 | } |
59e5aff5 | 2857 | (*chanids)[n] = -1; |
5260325f | 2858 | |
c9d0ad9b | 2859 | /* Return the display number for the DISPLAY environment variable. */ |
57f228e8 | 2860 | *display_numberp = display_number; |
2861 | return (0); | |
8efc0c15 | 2862 | } |
2863 | ||
396c147e | 2864 | static int |
1e3b8b07 | 2865 | connect_local_xsocket(u_int dnr) |
8efc0c15 | 2866 | { |
5260325f | 2867 | int sock; |
2868 | struct sockaddr_un addr; | |
5260325f | 2869 | |
805e659f | 2870 | sock = socket(AF_UNIX, SOCK_STREAM, 0); |
2871 | if (sock < 0) | |
2872 | error("socket: %.100s", strerror(errno)); | |
2873 | memset(&addr, 0, sizeof(addr)); | |
2874 | addr.sun_family = AF_UNIX; | |
2875 | snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr); | |
2876 | if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0) | |
2877 | return sock; | |
2878 | close(sock); | |
5260325f | 2879 | error("connect %.100s: %.100s", addr.sun_path, strerror(errno)); |
2880 | return -1; | |
8efc0c15 | 2881 | } |
2882 | ||
0b242b12 | 2883 | int |
2884 | x11_connect_display(void) | |
8efc0c15 | 2885 | { |
bcc0381e | 2886 | int display_number, sock = 0; |
5260325f | 2887 | const char *display; |
0b242b12 | 2888 | char buf[1024], *cp; |
48e671d5 | 2889 | struct addrinfo hints, *ai, *aitop; |
2890 | char strport[NI_MAXSERV]; | |
2891 | int gaierr; | |
5260325f | 2892 | |
5260325f | 2893 | /* Try to open a socket for the local X server. */ |
2894 | display = getenv("DISPLAY"); | |
2895 | if (!display) { | |
2896 | error("DISPLAY not set."); | |
0b242b12 | 2897 | return -1; |
5260325f | 2898 | } |
aa3378df | 2899 | /* |
2900 | * Now we decode the value of the DISPLAY variable and make a | |
2901 | * connection to the real X server. | |
2902 | */ | |
2903 | ||
2904 | /* | |
2905 | * Check if it is a unix domain socket. Unix domain displays are in | |
2906 | * one of the following formats: unix:d[.s], :d[.s], ::d[.s] | |
2907 | */ | |
5260325f | 2908 | if (strncmp(display, "unix:", 5) == 0 || |
2909 | display[0] == ':') { | |
2910 | /* Connect to the unix domain socket. */ | |
2911 | if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) { | |
2912 | error("Could not parse display number from DISPLAY: %.100s", | |
184eed6a | 2913 | display); |
0b242b12 | 2914 | return -1; |
5260325f | 2915 | } |
2916 | /* Create a socket. */ | |
2917 | sock = connect_local_xsocket(display_number); | |
2918 | if (sock < 0) | |
0b242b12 | 2919 | return -1; |
5260325f | 2920 | |
2921 | /* OK, we now have a connection to the display. */ | |
0b242b12 | 2922 | return sock; |
5260325f | 2923 | } |
aa3378df | 2924 | /* |
2925 | * Connect to an inet socket. The DISPLAY value is supposedly | |
2926 | * hostname:d[.s], where hostname may also be numeric IP address. | |
2927 | */ | |
74860245 | 2928 | strlcpy(buf, display, sizeof(buf)); |
5260325f | 2929 | cp = strchr(buf, ':'); |
2930 | if (!cp) { | |
2931 | error("Could not find ':' in DISPLAY: %.100s", display); | |
0b242b12 | 2932 | return -1; |
5260325f | 2933 | } |
2934 | *cp = 0; | |
aa3378df | 2935 | /* buf now contains the host name. But first we parse the display number. */ |
5260325f | 2936 | if (sscanf(cp + 1, "%d", &display_number) != 1) { |
2937 | error("Could not parse display number from DISPLAY: %.100s", | |
184eed6a | 2938 | display); |
0b242b12 | 2939 | return -1; |
5260325f | 2940 | } |
5260325f | 2941 | |
48e671d5 | 2942 | /* Look up the host address */ |
2943 | memset(&hints, 0, sizeof(hints)); | |
2944 | hints.ai_family = IPv4or6; | |
2945 | hints.ai_socktype = SOCK_STREAM; | |
2946 | snprintf(strport, sizeof strport, "%d", 6000 + display_number); | |
2947 | if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) { | |
2948 | error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr)); | |
0b242b12 | 2949 | return -1; |
8efc0c15 | 2950 | } |
48e671d5 | 2951 | for (ai = aitop; ai; ai = ai->ai_next) { |
2952 | /* Create a socket. */ | |
3e131a6d | 2953 | sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); |
48e671d5 | 2954 | if (sock < 0) { |
d7ac5f18 | 2955 | debug2("socket: %.100s", strerror(errno)); |
7368a6c8 | 2956 | continue; |
2957 | } | |
2958 | /* Connect it to the display. */ | |
2959 | if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
d7ac5f18 | 2960 | debug2("connect %.100s port %d: %.100s", buf, |
7368a6c8 | 2961 | 6000 + display_number, strerror(errno)); |
2962 | close(sock); | |
2963 | continue; | |
2964 | } | |
2965 | /* Success */ | |
2966 | break; | |
48e671d5 | 2967 | } |
48e671d5 | 2968 | freeaddrinfo(aitop); |
2969 | if (!ai) { | |
6ae2364d | 2970 | error("connect %.100s port %d: %.100s", buf, 6000 + display_number, |
48e671d5 | 2971 | strerror(errno)); |
0b242b12 | 2972 | return -1; |
8efc0c15 | 2973 | } |
bcc0381e | 2974 | set_nodelay(sock); |
0b242b12 | 2975 | return sock; |
2976 | } | |
5260325f | 2977 | |
0b242b12 | 2978 | /* |
2979 | * This is called when SSH_SMSG_X11_OPEN is received. The packet contains | |
2980 | * the remote channel number. We should do whatever we want, and respond | |
2981 | * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE. | |
2982 | */ | |
5260325f | 2983 | |
0b242b12 | 2984 | void |
7819b5c3 | 2985 | x11_input_open(int type, u_int32_t seq, void *ctxt) |
0b242b12 | 2986 | { |
719fc62f | 2987 | Channel *c = NULL; |
2988 | int remote_id, sock = 0; | |
0b242b12 | 2989 | char *remote_host; |
5260325f | 2990 | |
719fc62f | 2991 | debug("Received X11 open request."); |
5260325f | 2992 | |
719fc62f | 2993 | remote_id = packet_get_int(); |
8e7895b8 | 2994 | |
2995 | if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) { | |
719fc62f | 2996 | remote_host = packet_get_string(NULL); |
0b242b12 | 2997 | } else { |
2998 | remote_host = xstrdup("unknown (remote did not supply name)"); | |
0b242b12 | 2999 | } |
95500969 | 3000 | packet_check_eom(); |
0b242b12 | 3001 | |
3002 | /* Obtain a connection to the real X display. */ | |
3003 | sock = x11_connect_display(); | |
719fc62f | 3004 | if (sock != -1) { |
3005 | /* Allocate a channel for this connection. */ | |
3006 | c = channel_new("connected x11 socket", | |
3007 | SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0, | |
3008 | remote_host, 1); | |
3a0d3d54 | 3009 | c->remote_id = remote_id; |
3010 | c->force_drain = 1; | |
719fc62f | 3011 | } |
0d942eff | 3012 | xfree(remote_host); |
719fc62f | 3013 | if (c == NULL) { |
0b242b12 | 3014 | /* Send refusal to the remote host. */ |
3015 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
719fc62f | 3016 | packet_put_int(remote_id); |
0b242b12 | 3017 | } else { |
0b242b12 | 3018 | /* Send a confirmation to the remote host. */ |
3019 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
719fc62f | 3020 | packet_put_int(remote_id); |
3021 | packet_put_int(c->self); | |
0b242b12 | 3022 | } |
719fc62f | 3023 | packet_send(); |
8efc0c15 | 3024 | } |
3025 | ||
a22aff1f | 3026 | /* dummy protocol handler that denies SSH-1 requests (agent/x11) */ |
3027 | void | |
7819b5c3 | 3028 | deny_input_open(int type, u_int32_t seq, void *ctxt) |
a22aff1f | 3029 | { |
3030 | int rchan = packet_get_int(); | |
e1feb9bf | 3031 | |
6aacefa7 | 3032 | switch (type) { |
a22aff1f | 3033 | case SSH_SMSG_AGENT_OPEN: |
3034 | error("Warning: ssh server tried agent forwarding."); | |
3035 | break; | |
3036 | case SSH_SMSG_X11_OPEN: | |
3037 | error("Warning: ssh server tried X11 forwarding."); | |
3038 | break; | |
3039 | default: | |
7819b5c3 | 3040 | error("deny_input_open: type %d", type); |
a22aff1f | 3041 | break; |
3042 | } | |
1908529f | 3043 | error("Warning: this is probably a break-in attempt by a malicious server."); |
a22aff1f | 3044 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); |
3045 | packet_put_int(rchan); | |
3046 | packet_send(); | |
3047 | } | |
3048 | ||
aa3378df | 3049 | /* |
3050 | * Requests forwarding of X11 connections, generates fake authentication | |
3051 | * data, and enables authentication spoofing. | |
8e7895b8 | 3052 | * This should be called in the client only. |
aa3378df | 3053 | */ |
6ae2364d | 3054 | void |
9bf083eb | 3055 | x11_request_forwarding_with_spoofing(int client_session_id, const char *disp, |
0b242b12 | 3056 | const char *proto, const char *data) |
8efc0c15 | 3057 | { |
1e3b8b07 | 3058 | u_int data_len = (u_int) strlen(data) / 2; |
ef07103c | 3059 | u_int i, value; |
5260325f | 3060 | char *new_data; |
3061 | int screen_number; | |
3062 | const char *cp; | |
ca75d7de | 3063 | u_int32_t rnd = 0; |
5260325f | 3064 | |
4297b666 | 3065 | if (x11_saved_display == NULL) |
3066 | x11_saved_display = xstrdup(disp); | |
3067 | else if (strcmp(disp, x11_saved_display) != 0) { | |
ef07103c | 3068 | error("x11_request_forwarding_with_spoofing: different " |
3069 | "$DISPLAY already forwarded"); | |
3070 | return; | |
3071 | } | |
3072 | ||
9bf083eb | 3073 | cp = disp; |
3074 | if (disp) | |
3075 | cp = strchr(disp, ':'); | |
5260325f | 3076 | if (cp) |
3077 | cp = strchr(cp, '.'); | |
3078 | if (cp) | |
3079 | screen_number = atoi(cp + 1); | |
3080 | else | |
3081 | screen_number = 0; | |
3082 | ||
ef07103c | 3083 | if (x11_saved_proto == NULL) { |
3084 | /* Save protocol name. */ | |
3085 | x11_saved_proto = xstrdup(proto); | |
3086 | /* | |
56964485 | 3087 | * Extract real authentication data and generate fake data |
ef07103c | 3088 | * of the same length. |
3089 | */ | |
3090 | x11_saved_data = xmalloc(data_len); | |
3091 | x11_fake_data = xmalloc(data_len); | |
3092 | for (i = 0; i < data_len; i++) { | |
3093 | if (sscanf(data + 2 * i, "%2x", &value) != 1) | |
3094 | fatal("x11_request_forwarding: bad " | |
3095 | "authentication data: %.100s", data); | |
3096 | if (i % 4 == 0) | |
3097 | rnd = arc4random(); | |
3098 | x11_saved_data[i] = value; | |
3099 | x11_fake_data[i] = rnd & 0xff; | |
3100 | rnd >>= 8; | |
3101 | } | |
3102 | x11_saved_data_len = data_len; | |
3103 | x11_fake_data_len = data_len; | |
3104 | } | |
5260325f | 3105 | |
3106 | /* Convert the fake data into hex. */ | |
ef07103c | 3107 | new_data = tohex(x11_fake_data, data_len); |
5260325f | 3108 | |
3109 | /* Send the request packet. */ | |
0b242b12 | 3110 | if (compat20) { |
3111 | channel_request_start(client_session_id, "x11-req", 0); | |
3112 | packet_put_char(0); /* XXX bool single connection */ | |
3113 | } else { | |
3114 | packet_start(SSH_CMSG_X11_REQUEST_FORWARDING); | |
3115 | } | |
3116 | packet_put_cstring(proto); | |
3117 | packet_put_cstring(new_data); | |
5260325f | 3118 | packet_put_int(screen_number); |
3119 | packet_send(); | |
3120 | packet_write_wait(); | |
3121 | xfree(new_data); | |
8efc0c15 | 3122 | } |
3123 | ||
8e7895b8 | 3124 | |
3125 | /* -- agent forwarding */ | |
3126 | ||
8efc0c15 | 3127 | /* Sends a message to the server to request authentication fd forwarding. */ |
3128 | ||
6ae2364d | 3129 | void |
d5bb9418 | 3130 | auth_request_forwarding(void) |
8efc0c15 | 3131 | { |
5260325f | 3132 | packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING); |
3133 | packet_send(); | |
3134 | packet_write_wait(); | |
8efc0c15 | 3135 | } |