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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" | |
1d3e026f | 42 | RCSID("$OpenBSD: channels.c,v 1.233 2006/02/07 01:42:00 stevesk Exp $"); |
43 | ||
44 | #include <termios.h> | |
8efc0c15 | 45 | |
46 | #include "ssh.h" | |
42f11eb2 | 47 | #include "ssh1.h" |
48 | #include "ssh2.h" | |
8efc0c15 | 49 | #include "packet.h" |
50 | #include "xmalloc.h" | |
42f11eb2 | 51 | #include "log.h" |
52 | #include "misc.h" | |
8efc0c15 | 53 | #include "channels.h" |
8efc0c15 | 54 | #include "compat.h" |
42f11eb2 | 55 | #include "canohost.h" |
4c8722d9 | 56 | #include "key.h" |
57 | #include "authfd.h" | |
805e659f | 58 | #include "pathnames.h" |
f49658f5 | 59 | #include "bufaux.h" |
8efc0c15 | 60 | |
8e7895b8 | 61 | /* -- channel core */ |
8efc0c15 | 62 | |
aa3378df | 63 | /* |
64 | * Pointer to an array containing all allocated channels. The array is | |
65 | * dynamically extended as needed. | |
66 | */ | |
719fc62f | 67 | static Channel **channels = NULL; |
8efc0c15 | 68 | |
aa3378df | 69 | /* |
70 | * Size of the channel array. All slots of the array must always be | |
719fc62f | 71 | * initialized (at least the type field); unused slots set to NULL |
aa3378df | 72 | */ |
9a995072 | 73 | static u_int channels_alloc = 0; |
8efc0c15 | 74 | |
aa3378df | 75 | /* |
76 | * Maximum file descriptor value used in any of the channels. This is | |
719fc62f | 77 | * updated in channel_new. |
aa3378df | 78 | */ |
39929cdb | 79 | static int channel_max_fd = 0; |
8efc0c15 | 80 | |
8efc0c15 | 81 | |
8e7895b8 | 82 | /* -- tcp forwarding */ |
8efc0c15 | 83 | |
aa3378df | 84 | /* |
85 | * Data structure for storing which hosts are permitted for forward requests. | |
86 | * The local sides of any remote forwards are stored in this array to prevent | |
87 | * a corrupt remote server from accessing arbitrary TCP/IP ports on our local | |
88 | * network (which might be behind a firewall). | |
89 | */ | |
5260325f | 90 | typedef struct { |
7368a6c8 | 91 | char *host_to_connect; /* Connect to 'host'. */ |
92 | u_short port_to_connect; /* Connect to 'port'. */ | |
93 | u_short listen_port; /* Remote side should listen port number. */ | |
8efc0c15 | 94 | } ForwardPermission; |
95 | ||
96 | /* List of all permitted host/port pairs to connect. */ | |
97 | static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION]; | |
8e7895b8 | 98 | |
8efc0c15 | 99 | /* Number of permitted host/port pairs in the array. */ |
100 | static int num_permitted_opens = 0; | |
aa3378df | 101 | /* |
102 | * If this is true, all opens are permitted. This is the case on the server | |
103 | * on which we have to trust the client anyway, and the user could do | |
104 | * anything after logging in anyway. | |
105 | */ | |
8efc0c15 | 106 | static int all_opens_permitted = 0; |
107 | ||
8efc0c15 | 108 | |
8e7895b8 | 109 | /* -- X11 forwarding */ |
42f11eb2 | 110 | |
8e7895b8 | 111 | /* Maximum number of fake X11 displays to try. */ |
112 | #define MAX_DISPLAYS 1000 | |
0490e609 | 113 | |
ef07103c | 114 | /* Saved X11 local (client) display. */ |
115 | static char *x11_saved_display = NULL; | |
116 | ||
8e7895b8 | 117 | /* Saved X11 authentication protocol name. */ |
118 | static char *x11_saved_proto = NULL; | |
8efc0c15 | 119 | |
8e7895b8 | 120 | /* Saved X11 authentication data. This is the real data. */ |
121 | static char *x11_saved_data = NULL; | |
122 | static u_int x11_saved_data_len = 0; | |
123 | ||
124 | /* | |
125 | * Fake X11 authentication data. This is what the server will be sending us; | |
126 | * we should replace any occurrences of this by the real data. | |
127 | */ | |
128 | static char *x11_fake_data = NULL; | |
129 | static u_int x11_fake_data_len; | |
130 | ||
131 | ||
132 | /* -- agent forwarding */ | |
8efc0c15 | 133 | |
8e7895b8 | 134 | #define NUM_SOCKS 10 |
135 | ||
8e7895b8 | 136 | /* AF_UNSPEC or AF_INET or AF_INET6 */ |
5e4a7219 | 137 | static int IPv4or6 = AF_UNSPEC; |
8e7895b8 | 138 | |
139 | /* helper */ | |
396c147e | 140 | static void port_open_helper(Channel *c, char *rtype); |
8e7895b8 | 141 | |
142 | /* -- channel core */ | |
7368a6c8 | 143 | |
144 | Channel * | |
b872f7f0 | 145 | channel_by_id(int id) |
7368a6c8 | 146 | { |
147 | Channel *c; | |
719fc62f | 148 | |
9a995072 | 149 | if (id < 0 || (u_int)id >= channels_alloc) { |
b872f7f0 | 150 | logit("channel_by_id: %d: bad id", id); |
7368a6c8 | 151 | return NULL; |
152 | } | |
719fc62f | 153 | c = channels[id]; |
154 | if (c == NULL) { | |
b872f7f0 | 155 | logit("channel_by_id: %d: bad id: channel free", id); |
7368a6c8 | 156 | return NULL; |
157 | } | |
158 | return c; | |
159 | } | |
160 | ||
b872f7f0 | 161 | /* |
162 | * Returns the channel if it is allowed to receive protocol messages. | |
163 | * Private channels, like listening sockets, may not receive messages. | |
164 | */ | |
165 | Channel * | |
166 | channel_lookup(int id) | |
167 | { | |
168 | Channel *c; | |
169 | ||
170 | if ((c = channel_by_id(id)) == NULL) | |
171 | return (NULL); | |
172 | ||
173 | switch(c->type) { | |
174 | case SSH_CHANNEL_X11_OPEN: | |
175 | case SSH_CHANNEL_LARVAL: | |
176 | case SSH_CHANNEL_CONNECTING: | |
177 | case SSH_CHANNEL_DYNAMIC: | |
178 | case SSH_CHANNEL_OPENING: | |
179 | case SSH_CHANNEL_OPEN: | |
180 | case SSH_CHANNEL_INPUT_DRAINING: | |
181 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
182 | return (c); | |
183 | break; | |
184 | } | |
185 | logit("Non-public channel %d, type %d.", id, c->type); | |
186 | return (NULL); | |
187 | } | |
188 | ||
aa3378df | 189 | /* |
1d1ffb87 | 190 | * Register filedescriptors for a channel, used when allocating a channel or |
0fbe8c74 | 191 | * when the channel consumer/producer is ready, e.g. shell exec'd |
aa3378df | 192 | */ |
8efc0c15 | 193 | |
396c147e | 194 | static void |
a22aff1f | 195 | channel_register_fds(Channel *c, int rfd, int wfd, int efd, |
196 | int extusage, int nonblock) | |
8efc0c15 | 197 | { |
5260325f | 198 | /* Update the maximum file descriptor value. */ |
39929cdb | 199 | channel_max_fd = MAX(channel_max_fd, rfd); |
200 | channel_max_fd = MAX(channel_max_fd, wfd); | |
201 | channel_max_fd = MAX(channel_max_fd, efd); | |
202 | ||
aa3378df | 203 | /* XXX set close-on-exec -markus */ |
1d1ffb87 | 204 | |
0fbe8c74 | 205 | c->rfd = rfd; |
206 | c->wfd = wfd; | |
207 | c->sock = (rfd == wfd) ? rfd : -1; | |
5e96b616 | 208 | c->ctl_fd = -1; /* XXX: set elsewhere */ |
0fbe8c74 | 209 | c->efd = efd; |
210 | c->extended_usage = extusage; | |
a22aff1f | 211 | |
0ae4fe1d | 212 | /* XXX ugly hack: nonblock is only set by the server */ |
213 | if (nonblock && isatty(c->rfd)) { | |
d7ac5f18 | 214 | debug2("channel %d: rfd %d isatty", c->self, c->rfd); |
0ae4fe1d | 215 | c->isatty = 1; |
216 | if (!isatty(c->wfd)) { | |
94dfb550 | 217 | error("channel %d: wfd %d is not a tty?", |
0ae4fe1d | 218 | c->self, c->wfd); |
219 | } | |
220 | } else { | |
221 | c->isatty = 0; | |
222 | } | |
21c2c5cd | 223 | c->wfd_isatty = isatty(c->wfd); |
0ae4fe1d | 224 | |
a22aff1f | 225 | /* enable nonblocking mode */ |
226 | if (nonblock) { | |
227 | if (rfd != -1) | |
228 | set_nonblock(rfd); | |
229 | if (wfd != -1) | |
230 | set_nonblock(wfd); | |
231 | if (efd != -1) | |
232 | set_nonblock(efd); | |
233 | } | |
0fbe8c74 | 234 | } |
235 | ||
236 | /* | |
237 | * Allocate a new channel object and set its type and socket. This will cause | |
238 | * remote_name to be freed. | |
239 | */ | |
240 | ||
719fc62f | 241 | Channel * |
0fbe8c74 | 242 | channel_new(char *ctype, int type, int rfd, int wfd, int efd, |
f91d9a89 | 243 | u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock) |
0fbe8c74 | 244 | { |
9a995072 | 245 | int found; |
246 | u_int i; | |
0fbe8c74 | 247 | Channel *c; |
5260325f | 248 | |
249 | /* Do initial allocation if this is the first call. */ | |
250 | if (channels_alloc == 0) { | |
251 | channels_alloc = 10; | |
719fc62f | 252 | channels = xmalloc(channels_alloc * sizeof(Channel *)); |
5260325f | 253 | for (i = 0; i < channels_alloc; i++) |
719fc62f | 254 | channels[i] = NULL; |
5260325f | 255 | } |
256 | /* Try to find a free slot where to put the new channel. */ | |
257 | for (found = -1, i = 0; i < channels_alloc; i++) | |
719fc62f | 258 | if (channels[i] == NULL) { |
5260325f | 259 | /* Found a free slot. */ |
9a995072 | 260 | found = (int)i; |
5260325f | 261 | break; |
262 | } | |
9a995072 | 263 | if (found < 0) { |
aa3378df | 264 | /* There are no free slots. Take last+1 slot and expand the array. */ |
5260325f | 265 | found = channels_alloc; |
5df8c731 | 266 | if (channels_alloc > 10000) |
267 | fatal("channel_new: internal error: channels_alloc %d " | |
268 | "too big.", channels_alloc); | |
20419cc1 | 269 | channels = xrealloc(channels, |
270 | (channels_alloc + 10) * sizeof(Channel *)); | |
271 | channels_alloc += 10; | |
de273eef | 272 | debug2("channel: expanding %d", channels_alloc); |
5260325f | 273 | for (i = found; i < channels_alloc; i++) |
719fc62f | 274 | channels[i] = NULL; |
5260325f | 275 | } |
719fc62f | 276 | /* Initialize and return new channel. */ |
277 | c = channels[found] = xmalloc(sizeof(Channel)); | |
639cb8ab | 278 | memset(c, 0, sizeof(Channel)); |
5260325f | 279 | buffer_init(&c->input); |
280 | buffer_init(&c->output); | |
7368a6c8 | 281 | buffer_init(&c->extended); |
70bef40e | 282 | c->ostate = CHAN_OUTPUT_OPEN; |
283 | c->istate = CHAN_INPUT_OPEN; | |
284 | c->flags = 0; | |
a22aff1f | 285 | channel_register_fds(c, rfd, wfd, efd, extusage, nonblock); |
5260325f | 286 | c->self = found; |
287 | c->type = type; | |
7368a6c8 | 288 | c->ctype = ctype; |
0b242b12 | 289 | c->local_window = window; |
290 | c->local_window_max = window; | |
291 | c->local_consumed = 0; | |
292 | c->local_maxpacket = maxpack; | |
5260325f | 293 | c->remote_id = -1; |
0d942eff | 294 | c->remote_name = xstrdup(remote_name); |
7368a6c8 | 295 | c->remote_window = 0; |
296 | c->remote_maxpacket = 0; | |
a5f82435 | 297 | c->force_drain = 0; |
ac151b18 | 298 | c->single_connection = 0; |
3cf2be58 | 299 | c->detach_user = NULL; |
8cd0437d | 300 | c->detach_close = 0; |
05ca0898 | 301 | c->confirm = NULL; |
5e96b616 | 302 | c->confirm_ctx = NULL; |
2e73a022 | 303 | c->input_filter = NULL; |
c1c6a032 | 304 | c->output_filter = NULL; |
5260325f | 305 | debug("channel %d: new [%s]", found, remote_name); |
719fc62f | 306 | return c; |
7368a6c8 | 307 | } |
8efc0c15 | 308 | |
489aa2e9 | 309 | static int |
310 | channel_find_maxfd(void) | |
311 | { | |
9a995072 | 312 | u_int i; |
313 | int max = 0; | |
489aa2e9 | 314 | Channel *c; |
315 | ||
316 | for (i = 0; i < channels_alloc; i++) { | |
317 | c = channels[i]; | |
318 | if (c != NULL) { | |
319 | max = MAX(max, c->rfd); | |
320 | max = MAX(max, c->wfd); | |
321 | max = MAX(max, c->efd); | |
322 | } | |
323 | } | |
324 | return max; | |
325 | } | |
326 | ||
327 | int | |
328 | channel_close_fd(int *fdp) | |
329 | { | |
330 | int ret = 0, fd = *fdp; | |
331 | ||
332 | if (fd != -1) { | |
333 | ret = close(fd); | |
334 | *fdp = -1; | |
335 | if (fd == channel_max_fd) | |
336 | channel_max_fd = channel_find_maxfd(); | |
337 | } | |
338 | return ret; | |
339 | } | |
340 | ||
0fbe8c74 | 341 | /* Close all channel fd/socket. */ |
342 | ||
396c147e | 343 | static void |
0fbe8c74 | 344 | channel_close_fds(Channel *c) |
345 | { | |
5e96b616 | 346 | debug3("channel %d: close_fds r %d w %d e %d c %d", |
347 | c->self, c->rfd, c->wfd, c->efd, c->ctl_fd); | |
6fd8622b | 348 | |
489aa2e9 | 349 | channel_close_fd(&c->sock); |
5e96b616 | 350 | channel_close_fd(&c->ctl_fd); |
489aa2e9 | 351 | channel_close_fd(&c->rfd); |
352 | channel_close_fd(&c->wfd); | |
353 | channel_close_fd(&c->efd); | |
0fbe8c74 | 354 | } |
355 | ||
8e7895b8 | 356 | /* Free the channel and close its fd/socket. */ |
357 | ||
358 | void | |
359 | channel_free(Channel *c) | |
360 | { | |
361 | char *s; | |
9a995072 | 362 | u_int i, n; |
8e7895b8 | 363 | |
364 | for (n = 0, i = 0; i < channels_alloc; i++) | |
365 | if (channels[i]) | |
366 | n++; | |
9a995072 | 367 | debug("channel %d: free: %s, nchannels %u", c->self, |
8e7895b8 | 368 | c->remote_name ? c->remote_name : "???", n); |
369 | ||
370 | s = channel_open_message(); | |
d7ac5f18 | 371 | debug3("channel %d: status: %s", c->self, s); |
8e7895b8 | 372 | xfree(s); |
373 | ||
8e7895b8 | 374 | if (c->sock != -1) |
375 | shutdown(c->sock, SHUT_RDWR); | |
5e96b616 | 376 | if (c->ctl_fd != -1) |
377 | shutdown(c->ctl_fd, SHUT_RDWR); | |
8e7895b8 | 378 | channel_close_fds(c); |
379 | buffer_free(&c->input); | |
380 | buffer_free(&c->output); | |
381 | buffer_free(&c->extended); | |
382 | if (c->remote_name) { | |
383 | xfree(c->remote_name); | |
384 | c->remote_name = NULL; | |
385 | } | |
386 | channels[c->self] = NULL; | |
387 | xfree(c); | |
388 | } | |
389 | ||
8e7895b8 | 390 | void |
d6746a0b | 391 | channel_free_all(void) |
8e7895b8 | 392 | { |
9a995072 | 393 | u_int i; |
8e7895b8 | 394 | |
d6746a0b | 395 | for (i = 0; i < channels_alloc; i++) |
396 | if (channels[i] != NULL) | |
397 | channel_free(channels[i]); | |
8e7895b8 | 398 | } |
399 | ||
400 | /* | |
401 | * Closes the sockets/fds of all channels. This is used to close extra file | |
402 | * descriptors after a fork. | |
403 | */ | |
404 | ||
405 | void | |
d5bb9418 | 406 | channel_close_all(void) |
8e7895b8 | 407 | { |
9a995072 | 408 | u_int i; |
8e7895b8 | 409 | |
410 | for (i = 0; i < channels_alloc; i++) | |
411 | if (channels[i] != NULL) | |
412 | channel_close_fds(channels[i]); | |
413 | } | |
414 | ||
3cf2be58 | 415 | /* |
416 | * Stop listening to channels. | |
417 | */ | |
418 | ||
419 | void | |
420 | channel_stop_listening(void) | |
421 | { | |
9a995072 | 422 | u_int i; |
3cf2be58 | 423 | Channel *c; |
424 | ||
425 | for (i = 0; i < channels_alloc; i++) { | |
426 | c = channels[i]; | |
427 | if (c != NULL) { | |
428 | switch (c->type) { | |
429 | case SSH_CHANNEL_AUTH_SOCKET: | |
430 | case SSH_CHANNEL_PORT_LISTENER: | |
431 | case SSH_CHANNEL_RPORT_LISTENER: | |
432 | case SSH_CHANNEL_X11_LISTENER: | |
489aa2e9 | 433 | channel_close_fd(&c->sock); |
3cf2be58 | 434 | channel_free(c); |
435 | break; | |
436 | } | |
437 | } | |
438 | } | |
439 | } | |
440 | ||
8e7895b8 | 441 | /* |
442 | * Returns true if no channel has too much buffered data, and false if one or | |
443 | * more channel is overfull. | |
444 | */ | |
445 | ||
446 | int | |
d5bb9418 | 447 | channel_not_very_much_buffered_data(void) |
8e7895b8 | 448 | { |
449 | u_int i; | |
450 | Channel *c; | |
451 | ||
452 | for (i = 0; i < channels_alloc; i++) { | |
453 | c = channels[i]; | |
454 | if (c != NULL && c->type == SSH_CHANNEL_OPEN) { | |
0c139bd1 | 455 | #if 0 |
456 | if (!compat20 && | |
457 | buffer_len(&c->input) > packet_get_maxsize()) { | |
faa483fa | 458 | debug2("channel %d: big input buffer %d", |
8e7895b8 | 459 | c->self, buffer_len(&c->input)); |
460 | return 0; | |
461 | } | |
0c139bd1 | 462 | #endif |
8e7895b8 | 463 | if (buffer_len(&c->output) > packet_get_maxsize()) { |
a27002e5 | 464 | debug2("channel %d: big output buffer %u > %u", |
0c139bd1 | 465 | c->self, buffer_len(&c->output), |
466 | packet_get_maxsize()); | |
8e7895b8 | 467 | return 0; |
468 | } | |
469 | } | |
470 | } | |
471 | return 1; | |
472 | } | |
473 | ||
474 | /* Returns true if any channel is still open. */ | |
475 | ||
476 | int | |
d5bb9418 | 477 | channel_still_open(void) |
8e7895b8 | 478 | { |
9a995072 | 479 | u_int i; |
8e7895b8 | 480 | Channel *c; |
481 | ||
482 | for (i = 0; i < channels_alloc; i++) { | |
483 | c = channels[i]; | |
484 | if (c == NULL) | |
485 | continue; | |
486 | switch (c->type) { | |
487 | case SSH_CHANNEL_X11_LISTENER: | |
488 | case SSH_CHANNEL_PORT_LISTENER: | |
489 | case SSH_CHANNEL_RPORT_LISTENER: | |
490 | case SSH_CHANNEL_CLOSED: | |
491 | case SSH_CHANNEL_AUTH_SOCKET: | |
492 | case SSH_CHANNEL_DYNAMIC: | |
493 | case SSH_CHANNEL_CONNECTING: | |
494 | case SSH_CHANNEL_ZOMBIE: | |
495 | continue; | |
496 | case SSH_CHANNEL_LARVAL: | |
497 | if (!compat20) | |
498 | fatal("cannot happen: SSH_CHANNEL_LARVAL"); | |
499 | continue; | |
500 | case SSH_CHANNEL_OPENING: | |
501 | case SSH_CHANNEL_OPEN: | |
502 | case SSH_CHANNEL_X11_OPEN: | |
503 | return 1; | |
504 | case SSH_CHANNEL_INPUT_DRAINING: | |
505 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
506 | if (!compat13) | |
507 | fatal("cannot happen: OUT_DRAIN"); | |
508 | return 1; | |
509 | default: | |
510 | fatal("channel_still_open: bad channel type %d", c->type); | |
511 | /* NOTREACHED */ | |
512 | } | |
513 | } | |
514 | return 0; | |
515 | } | |
516 | ||
517 | /* Returns the id of an open channel suitable for keepaliving */ | |
518 | ||
519 | int | |
d5bb9418 | 520 | channel_find_open(void) |
8e7895b8 | 521 | { |
9a995072 | 522 | u_int i; |
8e7895b8 | 523 | Channel *c; |
524 | ||
525 | for (i = 0; i < channels_alloc; i++) { | |
526 | c = channels[i]; | |
13de3560 | 527 | if (c == NULL || c->remote_id < 0) |
8e7895b8 | 528 | continue; |
529 | switch (c->type) { | |
530 | case SSH_CHANNEL_CLOSED: | |
531 | case SSH_CHANNEL_DYNAMIC: | |
532 | case SSH_CHANNEL_X11_LISTENER: | |
533 | case SSH_CHANNEL_PORT_LISTENER: | |
534 | case SSH_CHANNEL_RPORT_LISTENER: | |
535 | case SSH_CHANNEL_OPENING: | |
536 | case SSH_CHANNEL_CONNECTING: | |
537 | case SSH_CHANNEL_ZOMBIE: | |
538 | continue; | |
539 | case SSH_CHANNEL_LARVAL: | |
540 | case SSH_CHANNEL_AUTH_SOCKET: | |
541 | case SSH_CHANNEL_OPEN: | |
542 | case SSH_CHANNEL_X11_OPEN: | |
543 | return i; | |
544 | case SSH_CHANNEL_INPUT_DRAINING: | |
545 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
546 | if (!compat13) | |
547 | fatal("cannot happen: OUT_DRAIN"); | |
548 | return i; | |
549 | default: | |
550 | fatal("channel_find_open: bad channel type %d", c->type); | |
551 | /* NOTREACHED */ | |
552 | } | |
553 | } | |
554 | return -1; | |
555 | } | |
556 | ||
557 | ||
558 | /* | |
559 | * Returns a message describing the currently open forwarded connections, | |
560 | * suitable for sending to the client. The message contains crlf pairs for | |
561 | * newlines. | |
562 | */ | |
563 | ||
564 | char * | |
d5bb9418 | 565 | channel_open_message(void) |
8e7895b8 | 566 | { |
567 | Buffer buffer; | |
568 | Channel *c; | |
569 | char buf[1024], *cp; | |
9a995072 | 570 | u_int i; |
8e7895b8 | 571 | |
572 | buffer_init(&buffer); | |
573 | snprintf(buf, sizeof buf, "The following connections are open:\r\n"); | |
574 | buffer_append(&buffer, buf, strlen(buf)); | |
575 | for (i = 0; i < channels_alloc; i++) { | |
576 | c = channels[i]; | |
577 | if (c == NULL) | |
578 | continue; | |
579 | switch (c->type) { | |
580 | case SSH_CHANNEL_X11_LISTENER: | |
581 | case SSH_CHANNEL_PORT_LISTENER: | |
582 | case SSH_CHANNEL_RPORT_LISTENER: | |
583 | case SSH_CHANNEL_CLOSED: | |
584 | case SSH_CHANNEL_AUTH_SOCKET: | |
585 | case SSH_CHANNEL_ZOMBIE: | |
586 | continue; | |
587 | case SSH_CHANNEL_LARVAL: | |
588 | case SSH_CHANNEL_OPENING: | |
589 | case SSH_CHANNEL_CONNECTING: | |
590 | case SSH_CHANNEL_DYNAMIC: | |
591 | case SSH_CHANNEL_OPEN: | |
592 | case SSH_CHANNEL_X11_OPEN: | |
593 | case SSH_CHANNEL_INPUT_DRAINING: | |
594 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
5e96b616 | 595 | snprintf(buf, sizeof buf, |
596 | " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d cfd %d)\r\n", | |
8e7895b8 | 597 | c->self, c->remote_name, |
598 | c->type, c->remote_id, | |
599 | c->istate, buffer_len(&c->input), | |
600 | c->ostate, buffer_len(&c->output), | |
5e96b616 | 601 | c->rfd, c->wfd, c->ctl_fd); |
8e7895b8 | 602 | buffer_append(&buffer, buf, strlen(buf)); |
603 | continue; | |
604 | default: | |
605 | fatal("channel_open_message: bad channel type %d", c->type); | |
606 | /* NOTREACHED */ | |
607 | } | |
608 | } | |
609 | buffer_append(&buffer, "\0", 1); | |
610 | cp = xstrdup(buffer_ptr(&buffer)); | |
611 | buffer_free(&buffer); | |
612 | return cp; | |
613 | } | |
614 | ||
615 | void | |
616 | channel_send_open(int id) | |
617 | { | |
618 | Channel *c = channel_lookup(id); | |
e1feb9bf | 619 | |
8e7895b8 | 620 | if (c == NULL) { |
bbe88b6d | 621 | logit("channel_send_open: %d: bad id", id); |
8e7895b8 | 622 | return; |
623 | } | |
6226a8f8 | 624 | debug2("channel %d: send open", id); |
8e7895b8 | 625 | packet_start(SSH2_MSG_CHANNEL_OPEN); |
626 | packet_put_cstring(c->ctype); | |
627 | packet_put_int(c->self); | |
628 | packet_put_int(c->local_window); | |
629 | packet_put_int(c->local_maxpacket); | |
630 | packet_send(); | |
631 | } | |
632 | ||
633 | void | |
6226a8f8 | 634 | channel_request_start(int id, char *service, int wantconfirm) |
8e7895b8 | 635 | { |
6226a8f8 | 636 | Channel *c = channel_lookup(id); |
e1feb9bf | 637 | |
8e7895b8 | 638 | if (c == NULL) { |
bbe88b6d | 639 | logit("channel_request_start: %d: unknown channel id", id); |
8e7895b8 | 640 | return; |
641 | } | |
5e96b616 | 642 | debug2("channel %d: request %s confirm %d", id, service, wantconfirm); |
8e7895b8 | 643 | packet_start(SSH2_MSG_CHANNEL_REQUEST); |
644 | packet_put_int(c->remote_id); | |
645 | packet_put_cstring(service); | |
646 | packet_put_char(wantconfirm); | |
647 | } | |
648 | void | |
5e96b616 | 649 | channel_register_confirm(int id, channel_callback_fn *fn, void *ctx) |
8e7895b8 | 650 | { |
651 | Channel *c = channel_lookup(id); | |
e1feb9bf | 652 | |
8e7895b8 | 653 | if (c == NULL) { |
bbe88b6d | 654 | logit("channel_register_comfirm: %d: bad id", id); |
8e7895b8 | 655 | return; |
656 | } | |
05ca0898 | 657 | c->confirm = fn; |
5e96b616 | 658 | c->confirm_ctx = ctx; |
8e7895b8 | 659 | } |
660 | void | |
8cd0437d | 661 | channel_register_cleanup(int id, channel_callback_fn *fn, int do_close) |
8e7895b8 | 662 | { |
b872f7f0 | 663 | Channel *c = channel_by_id(id); |
e1feb9bf | 664 | |
8e7895b8 | 665 | if (c == NULL) { |
bbe88b6d | 666 | logit("channel_register_cleanup: %d: bad id", id); |
8e7895b8 | 667 | return; |
668 | } | |
3cf2be58 | 669 | c->detach_user = fn; |
8cd0437d | 670 | c->detach_close = do_close; |
8e7895b8 | 671 | } |
672 | void | |
673 | channel_cancel_cleanup(int id) | |
674 | { | |
b872f7f0 | 675 | Channel *c = channel_by_id(id); |
e1feb9bf | 676 | |
8e7895b8 | 677 | if (c == NULL) { |
bbe88b6d | 678 | logit("channel_cancel_cleanup: %d: bad id", id); |
8e7895b8 | 679 | return; |
680 | } | |
3cf2be58 | 681 | c->detach_user = NULL; |
8cd0437d | 682 | c->detach_close = 0; |
8e7895b8 | 683 | } |
684 | void | |
c1c6a032 | 685 | channel_register_filter(int id, channel_infilter_fn *ifn, |
686 | channel_outfilter_fn *ofn) | |
8e7895b8 | 687 | { |
688 | Channel *c = channel_lookup(id); | |
e1feb9bf | 689 | |
8e7895b8 | 690 | if (c == NULL) { |
bbe88b6d | 691 | logit("channel_register_filter: %d: bad id", id); |
8e7895b8 | 692 | return; |
693 | } | |
c1c6a032 | 694 | c->input_filter = ifn; |
695 | c->output_filter = ofn; | |
8e7895b8 | 696 | } |
697 | ||
6ae2364d | 698 | void |
8e7895b8 | 699 | channel_set_fds(int id, int rfd, int wfd, int efd, |
399d1ea6 | 700 | int extusage, int nonblock, u_int window_max) |
8efc0c15 | 701 | { |
8e7895b8 | 702 | Channel *c = channel_lookup(id); |
e1feb9bf | 703 | |
8e7895b8 | 704 | if (c == NULL || c->type != SSH_CHANNEL_LARVAL) |
705 | fatal("channel_activate for non-larval channel %d.", id); | |
706 | channel_register_fds(c, rfd, wfd, efd, extusage, nonblock); | |
707 | c->type = SSH_CHANNEL_OPEN; | |
399d1ea6 | 708 | c->local_window = c->local_window_max = window_max; |
8e7895b8 | 709 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); |
710 | packet_put_int(c->remote_id); | |
711 | packet_put_int(c->local_window); | |
712 | packet_send(); | |
8efc0c15 | 713 | } |
714 | ||
aa3378df | 715 | /* |
7368a6c8 | 716 | * 'channel_pre*' are called just before select() to add any bits relevant to |
717 | * channels in the select bitmasks. | |
aa3378df | 718 | */ |
7368a6c8 | 719 | /* |
720 | * 'channel_post*': perform any appropriate operations for channels which | |
721 | * have events pending. | |
722 | */ | |
723 | typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset); | |
724 | chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE]; | |
725 | chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE]; | |
8efc0c15 | 726 | |
396c147e | 727 | static void |
7368a6c8 | 728 | channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset) |
8efc0c15 | 729 | { |
7368a6c8 | 730 | FD_SET(c->sock, readset); |
731 | } | |
5260325f | 732 | |
396c147e | 733 | static void |
97fb6912 | 734 | channel_pre_connecting(Channel *c, fd_set * readset, fd_set * writeset) |
735 | { | |
736 | debug3("channel %d: waiting for connection", c->self); | |
737 | FD_SET(c->sock, writeset); | |
738 | } | |
739 | ||
396c147e | 740 | static void |
7368a6c8 | 741 | channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset) |
742 | { | |
743 | if (buffer_len(&c->input) < packet_get_maxsize()) | |
744 | FD_SET(c->sock, readset); | |
745 | if (buffer_len(&c->output) > 0) | |
746 | FD_SET(c->sock, writeset); | |
747 | } | |
5260325f | 748 | |
396c147e | 749 | static void |
0c0738d5 | 750 | channel_pre_open(Channel *c, fd_set * readset, fd_set * writeset) |
7368a6c8 | 751 | { |
0c0738d5 | 752 | u_int limit = compat20 ? c->remote_window : packet_get_maxsize(); |
5260325f | 753 | |
fa1d7d85 | 754 | /* check buffer limits */ |
755 | limit = MIN(limit, (BUFFER_MAX_LEN - BUFFER_MAX_CHUNK - CHAN_RBUF)); | |
756 | ||
7e7327a1 | 757 | if (c->istate == CHAN_INPUT_OPEN && |
0c0738d5 | 758 | limit > 0 && |
759 | buffer_len(&c->input) < limit) | |
7e7327a1 | 760 | FD_SET(c->rfd, readset); |
761 | if (c->ostate == CHAN_OUTPUT_OPEN || | |
762 | c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
763 | if (buffer_len(&c->output) > 0) { | |
764 | FD_SET(c->wfd, writeset); | |
765 | } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
d2296ed7 | 766 | if (CHANNEL_EFD_OUTPUT_ACTIVE(c)) |
4e2e5cfd | 767 | debug2("channel %d: obuf_empty delayed efd %d/(%d)", |
768 | c->self, c->efd, buffer_len(&c->extended)); | |
d2296ed7 | 769 | else |
770 | chan_obuf_empty(c); | |
7e7327a1 | 771 | } |
772 | } | |
773 | /** XXX check close conditions, too */ | |
0c0738d5 | 774 | if (compat20 && c->efd != -1) { |
7e7327a1 | 775 | if (c->extended_usage == CHAN_EXTENDED_WRITE && |
776 | buffer_len(&c->extended) > 0) | |
777 | FD_SET(c->efd, writeset); | |
d2296ed7 | 778 | else if (!(c->flags & CHAN_EOF_SENT) && |
779 | c->extended_usage == CHAN_EXTENDED_READ && | |
7e7327a1 | 780 | buffer_len(&c->extended) < c->remote_window) |
781 | FD_SET(c->efd, readset); | |
782 | } | |
5e96b616 | 783 | /* XXX: What about efd? races? */ |
f2107e97 | 784 | if (compat20 && c->ctl_fd != -1 && |
5e96b616 | 785 | c->istate == CHAN_INPUT_OPEN && c->ostate == CHAN_OUTPUT_OPEN) |
786 | FD_SET(c->ctl_fd, readset); | |
7e7327a1 | 787 | } |
788 | ||
396c147e | 789 | static void |
7368a6c8 | 790 | channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset) |
791 | { | |
792 | if (buffer_len(&c->input) == 0) { | |
793 | packet_start(SSH_MSG_CHANNEL_CLOSE); | |
794 | packet_put_int(c->remote_id); | |
795 | packet_send(); | |
796 | c->type = SSH_CHANNEL_CLOSED; | |
d7ac5f18 | 797 | debug2("channel %d: closing after input drain.", c->self); |
7368a6c8 | 798 | } |
799 | } | |
5260325f | 800 | |
396c147e | 801 | static void |
7368a6c8 | 802 | channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset) |
803 | { | |
804 | if (buffer_len(&c->output) == 0) | |
719fc62f | 805 | chan_mark_dead(c); |
6ae2364d | 806 | else |
7368a6c8 | 807 | FD_SET(c->sock, writeset); |
808 | } | |
5260325f | 809 | |
7368a6c8 | 810 | /* |
811 | * This is a special state for X11 authentication spoofing. An opened X11 | |
812 | * connection (when authentication spoofing is being done) remains in this | |
813 | * state until the first packet has been completely read. The authentication | |
814 | * data in that packet is then substituted by the real data if it matches the | |
815 | * fake data, and the channel is put into normal mode. | |
0b242b12 | 816 | * XXX All this happens at the client side. |
8e7895b8 | 817 | * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok |
7368a6c8 | 818 | */ |
396c147e | 819 | static int |
8e7895b8 | 820 | x11_open_helper(Buffer *b) |
7368a6c8 | 821 | { |
1e3b8b07 | 822 | u_char *ucp; |
823 | u_int proto_len, data_len; | |
5260325f | 824 | |
7368a6c8 | 825 | /* Check if the fixed size part of the packet is in buffer. */ |
8e7895b8 | 826 | if (buffer_len(b) < 12) |
7368a6c8 | 827 | return 0; |
828 | ||
829 | /* Parse the lengths of variable-length fields. */ | |
20905a8e | 830 | ucp = buffer_ptr(b); |
7368a6c8 | 831 | if (ucp[0] == 0x42) { /* Byte order MSB first. */ |
832 | proto_len = 256 * ucp[6] + ucp[7]; | |
833 | data_len = 256 * ucp[8] + ucp[9]; | |
834 | } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */ | |
835 | proto_len = ucp[6] + 256 * ucp[7]; | |
836 | data_len = ucp[8] + 256 * ucp[9]; | |
837 | } else { | |
d7ac5f18 | 838 | debug2("Initial X11 packet contains bad byte order byte: 0x%x", |
184eed6a | 839 | ucp[0]); |
7368a6c8 | 840 | return -1; |
841 | } | |
5260325f | 842 | |
7368a6c8 | 843 | /* Check if the whole packet is in buffer. */ |
8e7895b8 | 844 | if (buffer_len(b) < |
7368a6c8 | 845 | 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3)) |
846 | return 0; | |
5260325f | 847 | |
7368a6c8 | 848 | /* Check if authentication protocol matches. */ |
849 | if (proto_len != strlen(x11_saved_proto) || | |
850 | memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) { | |
d7ac5f18 | 851 | debug2("X11 connection uses different authentication protocol."); |
7368a6c8 | 852 | return -1; |
853 | } | |
854 | /* Check if authentication data matches our fake data. */ | |
855 | if (data_len != x11_fake_data_len || | |
856 | memcmp(ucp + 12 + ((proto_len + 3) & ~3), | |
857 | x11_fake_data, x11_fake_data_len) != 0) { | |
d7ac5f18 | 858 | debug2("X11 auth data does not match fake data."); |
7368a6c8 | 859 | return -1; |
860 | } | |
861 | /* Check fake data length */ | |
862 | if (x11_fake_data_len != x11_saved_data_len) { | |
863 | error("X11 fake_data_len %d != saved_data_len %d", | |
864 | x11_fake_data_len, x11_saved_data_len); | |
865 | return -1; | |
866 | } | |
867 | /* | |
868 | * Received authentication protocol and data match | |
869 | * our fake data. Substitute the fake data with real | |
870 | * data. | |
871 | */ | |
872 | memcpy(ucp + 12 + ((proto_len + 3) & ~3), | |
873 | x11_saved_data, x11_saved_data_len); | |
874 | return 1; | |
875 | } | |
5260325f | 876 | |
396c147e | 877 | static void |
7368a6c8 | 878 | channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset) |
879 | { | |
8e7895b8 | 880 | int ret = x11_open_helper(&c->output); |
e1feb9bf | 881 | |
7368a6c8 | 882 | if (ret == 1) { |
883 | /* Start normal processing for the channel. */ | |
884 | c->type = SSH_CHANNEL_OPEN; | |
a8be9f80 | 885 | channel_pre_open_13(c, readset, writeset); |
7368a6c8 | 886 | } else if (ret == -1) { |
887 | /* | |
888 | * We have received an X11 connection that has bad | |
889 | * authentication information. | |
890 | */ | |
bbe88b6d | 891 | logit("X11 connection rejected because of wrong authentication."); |
7368a6c8 | 892 | buffer_clear(&c->input); |
893 | buffer_clear(&c->output); | |
489aa2e9 | 894 | channel_close_fd(&c->sock); |
7368a6c8 | 895 | c->sock = -1; |
896 | c->type = SSH_CHANNEL_CLOSED; | |
897 | packet_start(SSH_MSG_CHANNEL_CLOSE); | |
898 | packet_put_int(c->remote_id); | |
899 | packet_send(); | |
900 | } | |
901 | } | |
5260325f | 902 | |
396c147e | 903 | static void |
0b242b12 | 904 | channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset) |
7368a6c8 | 905 | { |
8e7895b8 | 906 | int ret = x11_open_helper(&c->output); |
a5f82435 | 907 | |
908 | /* c->force_drain = 1; */ | |
909 | ||
7368a6c8 | 910 | if (ret == 1) { |
911 | c->type = SSH_CHANNEL_OPEN; | |
0c0738d5 | 912 | channel_pre_open(c, readset, writeset); |
7368a6c8 | 913 | } else if (ret == -1) { |
bbe88b6d | 914 | logit("X11 connection rejected because of wrong authentication."); |
d7ac5f18 | 915 | debug2("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate); |
8341f420 | 916 | chan_read_failed(c); |
917 | buffer_clear(&c->input); | |
918 | chan_ibuf_empty(c); | |
919 | buffer_clear(&c->output); | |
920 | /* for proto v1, the peer will send an IEOF */ | |
921 | if (compat20) | |
922 | chan_write_failed(c); | |
923 | else | |
924 | c->type = SSH_CHANNEL_OPEN; | |
d7ac5f18 | 925 | debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate); |
7368a6c8 | 926 | } |
927 | } | |
5260325f | 928 | |
28b9cb4d | 929 | /* try to decode a socks4 header */ |
396c147e | 930 | static int |
28b9cb4d | 931 | channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset) |
0490e609 | 932 | { |
661e45a0 | 933 | char *p, *host; |
2ceb8101 | 934 | u_int len, have, i, found; |
184eed6a | 935 | char username[256]; |
0490e609 | 936 | struct { |
937 | u_int8_t version; | |
938 | u_int8_t command; | |
939 | u_int16_t dest_port; | |
28b9cb4d | 940 | struct in_addr dest_addr; |
0490e609 | 941 | } s4_req, s4_rsp; |
942 | ||
28b9cb4d | 943 | debug2("channel %d: decode socks4", c->self); |
53b8fe68 | 944 | |
945 | have = buffer_len(&c->input); | |
946 | len = sizeof(s4_req); | |
947 | if (have < len) | |
948 | return 0; | |
949 | p = buffer_ptr(&c->input); | |
950 | for (found = 0, i = len; i < have; i++) { | |
951 | if (p[i] == '\0') { | |
952 | found = 1; | |
953 | break; | |
954 | } | |
955 | if (i > 1024) { | |
956 | /* the peer is probably sending garbage */ | |
957 | debug("channel %d: decode socks4: too long", | |
958 | c->self); | |
959 | return -1; | |
960 | } | |
961 | } | |
962 | if (!found) | |
963 | return 0; | |
0490e609 | 964 | buffer_get(&c->input, (char *)&s4_req.version, 1); |
965 | buffer_get(&c->input, (char *)&s4_req.command, 1); | |
966 | buffer_get(&c->input, (char *)&s4_req.dest_port, 2); | |
28b9cb4d | 967 | buffer_get(&c->input, (char *)&s4_req.dest_addr, 4); |
53b8fe68 | 968 | have = buffer_len(&c->input); |
0490e609 | 969 | p = buffer_ptr(&c->input); |
970 | len = strlen(p); | |
6683b40f | 971 | debug2("channel %d: decode socks4: user %s/%d", c->self, p, len); |
0490e609 | 972 | if (len > have) |
28b9cb4d | 973 | fatal("channel %d: decode socks4: len %d > have %d", |
0490e609 | 974 | c->self, len, have); |
975 | strlcpy(username, p, sizeof(username)); | |
976 | buffer_consume(&c->input, len); | |
977 | buffer_consume(&c->input, 1); /* trailing '\0' */ | |
978 | ||
28b9cb4d | 979 | host = inet_ntoa(s4_req.dest_addr); |
0490e609 | 980 | strlcpy(c->path, host, sizeof(c->path)); |
981 | c->host_port = ntohs(s4_req.dest_port); | |
184eed6a | 982 | |
d7ac5f18 | 983 | debug2("channel %d: dynamic request: socks4 host %s port %u command %u", |
6683b40f | 984 | c->self, host, c->host_port, s4_req.command); |
0490e609 | 985 | |
28b9cb4d | 986 | if (s4_req.command != 1) { |
987 | debug("channel %d: cannot handle: socks4 cn %d", | |
988 | c->self, s4_req.command); | |
989 | return -1; | |
0490e609 | 990 | } |
28b9cb4d | 991 | s4_rsp.version = 0; /* vn: 0 for reply */ |
992 | s4_rsp.command = 90; /* cd: req granted */ | |
0490e609 | 993 | s4_rsp.dest_port = 0; /* ignored */ |
28b9cb4d | 994 | s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */ |
0490e609 | 995 | buffer_append(&c->output, (char *)&s4_rsp, sizeof(s4_rsp)); |
28b9cb4d | 996 | return 1; |
0490e609 | 997 | } |
998 | ||
f49658f5 | 999 | /* try to decode a socks5 header */ |
1000 | #define SSH_SOCKS5_AUTHDONE 0x1000 | |
1001 | #define SSH_SOCKS5_NOAUTH 0x00 | |
1002 | #define SSH_SOCKS5_IPV4 0x01 | |
1003 | #define SSH_SOCKS5_DOMAIN 0x03 | |
1004 | #define SSH_SOCKS5_IPV6 0x04 | |
1005 | #define SSH_SOCKS5_CONNECT 0x01 | |
1006 | #define SSH_SOCKS5_SUCCESS 0x00 | |
1007 | ||
1008 | static int | |
1009 | channel_decode_socks5(Channel *c, fd_set * readset, fd_set * writeset) | |
1010 | { | |
1011 | struct { | |
1012 | u_int8_t version; | |
1013 | u_int8_t command; | |
1014 | u_int8_t reserved; | |
1015 | u_int8_t atyp; | |
1016 | } s5_req, s5_rsp; | |
1017 | u_int16_t dest_port; | |
1018 | u_char *p, dest_addr[255+1]; | |
2ceb8101 | 1019 | u_int have, i, found, nmethods, addrlen, af; |
f49658f5 | 1020 | |
1021 | debug2("channel %d: decode socks5", c->self); | |
1022 | p = buffer_ptr(&c->input); | |
1023 | if (p[0] != 0x05) | |
1024 | return -1; | |
1025 | have = buffer_len(&c->input); | |
1026 | if (!(c->flags & SSH_SOCKS5_AUTHDONE)) { | |
1027 | /* format: ver | nmethods | methods */ | |
aff51935 | 1028 | if (have < 2) |
f49658f5 | 1029 | return 0; |
1030 | nmethods = p[1]; | |
1031 | if (have < nmethods + 2) | |
1032 | return 0; | |
1033 | /* look for method: "NO AUTHENTICATION REQUIRED" */ | |
1034 | for (found = 0, i = 2 ; i < nmethods + 2; i++) { | |
1035 | if (p[i] == SSH_SOCKS5_NOAUTH ) { | |
1036 | found = 1; | |
1037 | break; | |
1038 | } | |
1039 | } | |
1040 | if (!found) { | |
1041 | debug("channel %d: method SSH_SOCKS5_NOAUTH not found", | |
1042 | c->self); | |
1043 | return -1; | |
1044 | } | |
1045 | buffer_consume(&c->input, nmethods + 2); | |
1046 | buffer_put_char(&c->output, 0x05); /* version */ | |
1047 | buffer_put_char(&c->output, SSH_SOCKS5_NOAUTH); /* method */ | |
1048 | FD_SET(c->sock, writeset); | |
1049 | c->flags |= SSH_SOCKS5_AUTHDONE; | |
1050 | debug2("channel %d: socks5 auth done", c->self); | |
1051 | return 0; /* need more */ | |
1052 | } | |
1053 | debug2("channel %d: socks5 post auth", c->self); | |
1054 | if (have < sizeof(s5_req)+1) | |
1055 | return 0; /* need more */ | |
1056 | memcpy((char *)&s5_req, p, sizeof(s5_req)); | |
1057 | if (s5_req.version != 0x05 || | |
1058 | s5_req.command != SSH_SOCKS5_CONNECT || | |
1059 | s5_req.reserved != 0x00) { | |
d7ac5f18 | 1060 | debug2("channel %d: only socks5 connect supported", c->self); |
f49658f5 | 1061 | return -1; |
1062 | } | |
f8cc7664 | 1063 | switch (s5_req.atyp){ |
f49658f5 | 1064 | case SSH_SOCKS5_IPV4: |
1065 | addrlen = 4; | |
1066 | af = AF_INET; | |
1067 | break; | |
1068 | case SSH_SOCKS5_DOMAIN: | |
1069 | addrlen = p[sizeof(s5_req)]; | |
1070 | af = -1; | |
1071 | break; | |
1072 | case SSH_SOCKS5_IPV6: | |
1073 | addrlen = 16; | |
1074 | af = AF_INET6; | |
1075 | break; | |
1076 | default: | |
d7ac5f18 | 1077 | debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp); |
f49658f5 | 1078 | return -1; |
1079 | } | |
1080 | if (have < 4 + addrlen + 2) | |
1081 | return 0; | |
1082 | buffer_consume(&c->input, sizeof(s5_req)); | |
1083 | if (s5_req.atyp == SSH_SOCKS5_DOMAIN) | |
1084 | buffer_consume(&c->input, 1); /* host string length */ | |
1085 | buffer_get(&c->input, (char *)&dest_addr, addrlen); | |
1086 | buffer_get(&c->input, (char *)&dest_port, 2); | |
1087 | dest_addr[addrlen] = '\0'; | |
1088 | if (s5_req.atyp == SSH_SOCKS5_DOMAIN) | |
f6be21a0 | 1089 | strlcpy(c->path, (char *)dest_addr, sizeof(c->path)); |
f49658f5 | 1090 | else if (inet_ntop(af, dest_addr, c->path, sizeof(c->path)) == NULL) |
1091 | return -1; | |
1092 | c->host_port = ntohs(dest_port); | |
b6453d99 | 1093 | |
d7ac5f18 | 1094 | debug2("channel %d: dynamic request: socks5 host %s port %u command %u", |
f49658f5 | 1095 | c->self, c->path, c->host_port, s5_req.command); |
1096 | ||
1097 | s5_rsp.version = 0x05; | |
1098 | s5_rsp.command = SSH_SOCKS5_SUCCESS; | |
1099 | s5_rsp.reserved = 0; /* ignored */ | |
1100 | s5_rsp.atyp = SSH_SOCKS5_IPV4; | |
1101 | ((struct in_addr *)&dest_addr)->s_addr = INADDR_ANY; | |
1102 | dest_port = 0; /* ignored */ | |
1103 | ||
1104 | buffer_append(&c->output, (char *)&s5_rsp, sizeof(s5_rsp)); | |
1105 | buffer_append(&c->output, (char *)&dest_addr, sizeof(struct in_addr)); | |
1106 | buffer_append(&c->output, (char *)&dest_port, sizeof(dest_port)); | |
1107 | return 1; | |
1108 | } | |
1109 | ||
28b9cb4d | 1110 | /* dynamic port forwarding */ |
396c147e | 1111 | static void |
28b9cb4d | 1112 | channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset) |
1113 | { | |
1114 | u_char *p; | |
2ceb8101 | 1115 | u_int have; |
1116 | int ret; | |
28b9cb4d | 1117 | |
1118 | have = buffer_len(&c->input); | |
639cb8ab | 1119 | c->delayed = 0; |
28b9cb4d | 1120 | debug2("channel %d: pre_dynamic: have %d", c->self, have); |
070adba2 | 1121 | /* buffer_dump(&c->input); */ |
28b9cb4d | 1122 | /* check if the fixed size part of the packet is in buffer. */ |
f49658f5 | 1123 | if (have < 3) { |
28b9cb4d | 1124 | /* need more */ |
1125 | FD_SET(c->sock, readset); | |
1126 | return; | |
1127 | } | |
1128 | /* try to guess the protocol */ | |
1129 | p = buffer_ptr(&c->input); | |
1130 | switch (p[0]) { | |
6683b40f | 1131 | case 0x04: |
1132 | ret = channel_decode_socks4(c, readset, writeset); | |
1133 | break; | |
f49658f5 | 1134 | case 0x05: |
1135 | ret = channel_decode_socks5(c, readset, writeset); | |
1136 | break; | |
28b9cb4d | 1137 | default: |
1138 | ret = -1; | |
1139 | break; | |
1140 | } | |
1141 | if (ret < 0) { | |
719fc62f | 1142 | chan_mark_dead(c); |
28b9cb4d | 1143 | } else if (ret == 0) { |
1144 | debug2("channel %d: pre_dynamic: need more", c->self); | |
1145 | /* need more */ | |
1146 | FD_SET(c->sock, readset); | |
1147 | } else { | |
1148 | /* switch to the next state */ | |
1149 | c->type = SSH_CHANNEL_OPENING; | |
1150 | port_open_helper(c, "direct-tcpip"); | |
1151 | } | |
1152 | } | |
0490e609 | 1153 | |
7368a6c8 | 1154 | /* This is our fake X11 server socket. */ |
396c147e | 1155 | static void |
7368a6c8 | 1156 | channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset) |
1157 | { | |
719fc62f | 1158 | Channel *nc; |
7368a6c8 | 1159 | struct sockaddr addr; |
bcc0381e | 1160 | int newsock; |
7368a6c8 | 1161 | socklen_t addrlen; |
865ac82e | 1162 | char buf[16384], *remote_ipaddr; |
0b242b12 | 1163 | int remote_port; |
7368a6c8 | 1164 | |
1165 | if (FD_ISSET(c->sock, readset)) { | |
1166 | debug("X11 connection requested."); | |
1167 | addrlen = sizeof(addr); | |
1168 | newsock = accept(c->sock, &addr, &addrlen); | |
ac151b18 | 1169 | if (c->single_connection) { |
d7ac5f18 | 1170 | debug2("single_connection: closing X11 listener."); |
ac151b18 | 1171 | channel_close_fd(&c->sock); |
1172 | chan_mark_dead(c); | |
1173 | } | |
7368a6c8 | 1174 | if (newsock < 0) { |
1175 | error("accept: %.100s", strerror(errno)); | |
1176 | return; | |
5260325f | 1177 | } |
bcc0381e | 1178 | set_nodelay(newsock); |
865ac82e | 1179 | remote_ipaddr = get_peer_ipaddr(newsock); |
0b242b12 | 1180 | remote_port = get_peer_port(newsock); |
7368a6c8 | 1181 | snprintf(buf, sizeof buf, "X11 connection from %.200s port %d", |
865ac82e | 1182 | remote_ipaddr, remote_port); |
0b242b12 | 1183 | |
719fc62f | 1184 | nc = channel_new("accepted x11 socket", |
0b242b12 | 1185 | SSH_CHANNEL_OPENING, newsock, newsock, -1, |
0d942eff | 1186 | c->local_window_max, c->local_maxpacket, 0, buf, 1); |
0b242b12 | 1187 | if (compat20) { |
1188 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
1189 | packet_put_cstring("x11"); | |
719fc62f | 1190 | packet_put_int(nc->self); |
ac151b18 | 1191 | packet_put_int(nc->local_window_max); |
1192 | packet_put_int(nc->local_maxpacket); | |
865ac82e | 1193 | /* originator ipaddr and port */ |
1194 | packet_put_cstring(remote_ipaddr); | |
d0c832f3 | 1195 | if (datafellows & SSH_BUG_X11FWD) { |
d7ac5f18 | 1196 | debug2("ssh2 x11 bug compat mode"); |
d0c832f3 | 1197 | } else { |
1198 | packet_put_int(remote_port); | |
1199 | } | |
0b242b12 | 1200 | packet_send(); |
1201 | } else { | |
1202 | packet_start(SSH_SMSG_X11_OPEN); | |
719fc62f | 1203 | packet_put_int(nc->self); |
8e7895b8 | 1204 | if (packet_get_protocol_flags() & |
1205 | SSH_PROTOFLAG_HOST_IN_FWD_OPEN) | |
449c5ba5 | 1206 | packet_put_cstring(buf); |
0b242b12 | 1207 | packet_send(); |
1208 | } | |
865ac82e | 1209 | xfree(remote_ipaddr); |
8efc0c15 | 1210 | } |
8efc0c15 | 1211 | } |
1212 | ||
396c147e | 1213 | static void |
0490e609 | 1214 | port_open_helper(Channel *c, char *rtype) |
1215 | { | |
1216 | int direct; | |
1217 | char buf[1024]; | |
1218 | char *remote_ipaddr = get_peer_ipaddr(c->sock); | |
29798ed0 | 1219 | int remote_port = get_peer_port(c->sock); |
0490e609 | 1220 | |
1221 | direct = (strcmp(rtype, "direct-tcpip") == 0); | |
1222 | ||
1223 | snprintf(buf, sizeof buf, | |
1224 | "%s: listening port %d for %.100s port %d, " | |
1225 | "connect from %.200s port %d", | |
1226 | rtype, c->listening_port, c->path, c->host_port, | |
1227 | remote_ipaddr, remote_port); | |
1228 | ||
1229 | xfree(c->remote_name); | |
1230 | c->remote_name = xstrdup(buf); | |
1231 | ||
1232 | if (compat20) { | |
1233 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
1234 | packet_put_cstring(rtype); | |
1235 | packet_put_int(c->self); | |
1236 | packet_put_int(c->local_window_max); | |
1237 | packet_put_int(c->local_maxpacket); | |
1238 | if (direct) { | |
1239 | /* target host, port */ | |
1240 | packet_put_cstring(c->path); | |
1241 | packet_put_int(c->host_port); | |
1242 | } else { | |
1243 | /* listen address, port */ | |
1244 | packet_put_cstring(c->path); | |
1245 | packet_put_int(c->listening_port); | |
1246 | } | |
1247 | /* originator host and port */ | |
1248 | packet_put_cstring(remote_ipaddr); | |
29798ed0 | 1249 | packet_put_int((u_int)remote_port); |
0490e609 | 1250 | packet_send(); |
1251 | } else { | |
1252 | packet_start(SSH_MSG_PORT_OPEN); | |
1253 | packet_put_int(c->self); | |
1254 | packet_put_cstring(c->path); | |
1255 | packet_put_int(c->host_port); | |
8e7895b8 | 1256 | if (packet_get_protocol_flags() & |
1257 | SSH_PROTOFLAG_HOST_IN_FWD_OPEN) | |
0490e609 | 1258 | packet_put_cstring(c->remote_name); |
1259 | packet_send(); | |
1260 | } | |
1261 | xfree(remote_ipaddr); | |
1262 | } | |
1263 | ||
442aee3a | 1264 | static void |
1265 | channel_set_reuseaddr(int fd) | |
1266 | { | |
1267 | int on = 1; | |
1268 | ||
1269 | /* | |
1270 | * Set socket options. | |
1271 | * Allow local port reuse in TIME_WAIT. | |
1272 | */ | |
1273 | if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1) | |
1274 | error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno)); | |
1275 | } | |
1276 | ||
aa3378df | 1277 | /* |
7368a6c8 | 1278 | * This socket is listening for connections to a forwarded TCP/IP port. |
aa3378df | 1279 | */ |
396c147e | 1280 | static void |
7368a6c8 | 1281 | channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset) |
1282 | { | |
0490e609 | 1283 | Channel *nc; |
7368a6c8 | 1284 | struct sockaddr addr; |
719fc62f | 1285 | int newsock, nextstate; |
7368a6c8 | 1286 | socklen_t addrlen; |
0490e609 | 1287 | char *rtype; |
fa08c86b | 1288 | |
7368a6c8 | 1289 | if (FD_ISSET(c->sock, readset)) { |
1290 | debug("Connection to port %d forwarding " | |
1291 | "to %.100s port %d requested.", | |
1292 | c->listening_port, c->path, c->host_port); | |
0490e609 | 1293 | |
639cb8ab | 1294 | if (c->type == SSH_CHANNEL_RPORT_LISTENER) { |
1295 | nextstate = SSH_CHANNEL_OPENING; | |
1296 | rtype = "forwarded-tcpip"; | |
1297 | } else { | |
1298 | if (c->host_port == 0) { | |
1299 | nextstate = SSH_CHANNEL_DYNAMIC; | |
f3964cb9 | 1300 | rtype = "dynamic-tcpip"; |
639cb8ab | 1301 | } else { |
1302 | nextstate = SSH_CHANNEL_OPENING; | |
1303 | rtype = "direct-tcpip"; | |
1304 | } | |
1305 | } | |
0490e609 | 1306 | |
7368a6c8 | 1307 | addrlen = sizeof(addr); |
1308 | newsock = accept(c->sock, &addr, &addrlen); | |
1309 | if (newsock < 0) { | |
1310 | error("accept: %.100s", strerror(errno)); | |
1311 | return; | |
1312 | } | |
811a6342 | 1313 | set_nodelay(newsock); |
0d942eff | 1314 | nc = channel_new(rtype, nextstate, newsock, newsock, -1, |
1315 | c->local_window_max, c->local_maxpacket, 0, rtype, 1); | |
0490e609 | 1316 | nc->listening_port = c->listening_port; |
1317 | nc->host_port = c->host_port; | |
1318 | strlcpy(nc->path, c->path, sizeof(nc->path)); | |
1319 | ||
639cb8ab | 1320 | if (nextstate == SSH_CHANNEL_DYNAMIC) { |
1321 | /* | |
1322 | * do not call the channel_post handler until | |
1323 | * this flag has been reset by a pre-handler. | |
1324 | * otherwise the FD_ISSET calls might overflow | |
1325 | */ | |
1326 | nc->delayed = 1; | |
1327 | } else { | |
0490e609 | 1328 | port_open_helper(nc, rtype); |
639cb8ab | 1329 | } |
7368a6c8 | 1330 | } |
1331 | } | |
8efc0c15 | 1332 | |
7368a6c8 | 1333 | /* |
1334 | * This is the authentication agent socket listening for connections from | |
1335 | * clients. | |
1336 | */ | |
396c147e | 1337 | static void |
7368a6c8 | 1338 | channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset) |
8efc0c15 | 1339 | { |
719fc62f | 1340 | Channel *nc; |
1341 | int newsock; | |
5260325f | 1342 | struct sockaddr addr; |
48e671d5 | 1343 | socklen_t addrlen; |
5260325f | 1344 | |
7368a6c8 | 1345 | if (FD_ISSET(c->sock, readset)) { |
1346 | addrlen = sizeof(addr); | |
1347 | newsock = accept(c->sock, &addr, &addrlen); | |
1348 | if (newsock < 0) { | |
1349 | error("accept from auth socket: %.100s", strerror(errno)); | |
1350 | return; | |
1351 | } | |
719fc62f | 1352 | nc = channel_new("accepted auth socket", |
fa08c86b | 1353 | SSH_CHANNEL_OPENING, newsock, newsock, -1, |
1354 | c->local_window_max, c->local_maxpacket, | |
0d942eff | 1355 | 0, "accepted auth socket", 1); |
fa08c86b | 1356 | if (compat20) { |
1357 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
1358 | packet_put_cstring("auth-agent@openssh.com"); | |
719fc62f | 1359 | packet_put_int(nc->self); |
fa08c86b | 1360 | packet_put_int(c->local_window_max); |
1361 | packet_put_int(c->local_maxpacket); | |
1362 | } else { | |
1363 | packet_start(SSH_SMSG_AGENT_OPEN); | |
719fc62f | 1364 | packet_put_int(nc->self); |
fa08c86b | 1365 | } |
7368a6c8 | 1366 | packet_send(); |
1367 | } | |
1368 | } | |
5260325f | 1369 | |
396c147e | 1370 | static void |
97fb6912 | 1371 | channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset) |
1372 | { | |
d18e0850 | 1373 | int err = 0; |
8ab2cb35 | 1374 | socklen_t sz = sizeof(err); |
d18e0850 | 1375 | |
97fb6912 | 1376 | if (FD_ISSET(c->sock, writeset)) { |
db518d9b | 1377 | if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) { |
d18e0850 | 1378 | err = errno; |
1379 | error("getsockopt SO_ERROR failed"); | |
1380 | } | |
1381 | if (err == 0) { | |
1382 | debug("channel %d: connected", c->self); | |
1383 | c->type = SSH_CHANNEL_OPEN; | |
1384 | if (compat20) { | |
1385 | packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1386 | packet_put_int(c->remote_id); | |
1387 | packet_put_int(c->self); | |
1388 | packet_put_int(c->local_window); | |
1389 | packet_put_int(c->local_maxpacket); | |
1390 | } else { | |
1391 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1392 | packet_put_int(c->remote_id); | |
1393 | packet_put_int(c->self); | |
1394 | } | |
97fb6912 | 1395 | } else { |
d18e0850 | 1396 | debug("channel %d: not connected: %s", |
1397 | c->self, strerror(err)); | |
1398 | if (compat20) { | |
1399 | packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE); | |
1400 | packet_put_int(c->remote_id); | |
1401 | packet_put_int(SSH2_OPEN_CONNECT_FAILED); | |
1402 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { | |
1403 | packet_put_cstring(strerror(err)); | |
1404 | packet_put_cstring(""); | |
1405 | } | |
97fb6912 | 1406 | } else { |
d18e0850 | 1407 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); |
1408 | packet_put_int(c->remote_id); | |
97fb6912 | 1409 | } |
d18e0850 | 1410 | chan_mark_dead(c); |
97fb6912 | 1411 | } |
d18e0850 | 1412 | packet_send(); |
97fb6912 | 1413 | } |
1414 | } | |
1415 | ||
396c147e | 1416 | static int |
7368a6c8 | 1417 | channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset) |
1418 | { | |
fa1d7d85 | 1419 | char buf[CHAN_RBUF]; |
7368a6c8 | 1420 | int len; |
1421 | ||
6fd8622b | 1422 | if (c->rfd != -1 && |
7368a6c8 | 1423 | FD_ISSET(c->rfd, readset)) { |
1424 | len = read(c->rfd, buf, sizeof(buf)); | |
0fbe8c74 | 1425 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1426 | return 1; | |
7368a6c8 | 1427 | if (len <= 0) { |
d7ac5f18 | 1428 | debug2("channel %d: read<=0 rfd %d len %d", |
7368a6c8 | 1429 | c->self, c->rfd, len); |
28b9cb4d | 1430 | if (c->type != SSH_CHANNEL_OPEN) { |
d7ac5f18 | 1431 | debug2("channel %d: not open", c->self); |
719fc62f | 1432 | chan_mark_dead(c); |
0490e609 | 1433 | return -1; |
28b9cb4d | 1434 | } else if (compat13) { |
9c50edcf | 1435 | buffer_clear(&c->output); |
7368a6c8 | 1436 | c->type = SSH_CHANNEL_INPUT_DRAINING; |
d7ac5f18 | 1437 | debug2("channel %d: input draining.", c->self); |
7368a6c8 | 1438 | } else { |
1439 | chan_read_failed(c); | |
5260325f | 1440 | } |
7368a6c8 | 1441 | return -1; |
1442 | } | |
6aacefa7 | 1443 | if (c->input_filter != NULL) { |
2e73a022 | 1444 | if (c->input_filter(c, buf, len) == -1) { |
d7ac5f18 | 1445 | debug2("channel %d: filter stops", c->self); |
2e73a022 | 1446 | chan_read_failed(c); |
1447 | } | |
d20f3c9e | 1448 | } else if (c->datagram) { |
1449 | buffer_put_string(&c->input, buf, len); | |
2e73a022 | 1450 | } else { |
1451 | buffer_append(&c->input, buf, len); | |
1452 | } | |
7368a6c8 | 1453 | } |
1454 | return 1; | |
1455 | } | |
396c147e | 1456 | static int |
7368a6c8 | 1457 | channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset) |
1458 | { | |
95ce5599 | 1459 | struct termios tio; |
c1c6a032 | 1460 | u_char *data = NULL, *buf; |
780a9951 | 1461 | u_int dlen; |
7368a6c8 | 1462 | int len; |
1463 | ||
1464 | /* Send buffered output data to the socket. */ | |
6fd8622b | 1465 | if (c->wfd != -1 && |
7368a6c8 | 1466 | FD_ISSET(c->wfd, writeset) && |
1467 | buffer_len(&c->output) > 0) { | |
c1c6a032 | 1468 | if (c->output_filter != NULL) { |
1469 | if ((buf = c->output_filter(c, &data, &dlen)) == NULL) { | |
1470 | debug2("channel %d: filter stops", c->self); | |
d7b37427 | 1471 | if (c->type != SSH_CHANNEL_OPEN) |
1472 | chan_mark_dead(c); | |
1473 | else | |
1474 | chan_write_failed(c); | |
1475 | return -1; | |
c1c6a032 | 1476 | } |
1477 | } else if (c->datagram) { | |
1478 | buf = data = buffer_get_string(&c->output, &dlen); | |
1479 | } else { | |
1480 | buf = data = buffer_ptr(&c->output); | |
1481 | dlen = buffer_len(&c->output); | |
1482 | } | |
1483 | ||
d20f3c9e | 1484 | if (c->datagram) { |
d20f3c9e | 1485 | /* ignore truncated writes, datagrams might get lost */ |
1486 | c->local_consumed += dlen + 4; | |
c1c6a032 | 1487 | len = write(c->wfd, buf, dlen); |
d20f3c9e | 1488 | xfree(data); |
1489 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) | |
1490 | return 1; | |
1491 | if (len <= 0) { | |
1492 | if (c->type != SSH_CHANNEL_OPEN) | |
1493 | chan_mark_dead(c); | |
1494 | else | |
1495 | chan_write_failed(c); | |
1496 | return -1; | |
1497 | } | |
1498 | return 1; | |
1499 | } | |
64c0ce80 | 1500 | #ifdef _AIX |
aff51935 | 1501 | /* XXX: Later AIX versions can't push as much data to tty */ |
7fbb4189 | 1502 | if (compat20 && c->wfd_isatty) |
1503 | dlen = MIN(dlen, 8*1024); | |
64c0ce80 | 1504 | #endif |
c1c6a032 | 1505 | |
1506 | len = write(c->wfd, buf, dlen); | |
0fbe8c74 | 1507 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1508 | return 1; | |
7368a6c8 | 1509 | if (len <= 0) { |
28b9cb4d | 1510 | if (c->type != SSH_CHANNEL_OPEN) { |
d7ac5f18 | 1511 | debug2("channel %d: not open", c->self); |
719fc62f | 1512 | chan_mark_dead(c); |
28b9cb4d | 1513 | return -1; |
1514 | } else if (compat13) { | |
9c50edcf | 1515 | buffer_clear(&c->output); |
d7ac5f18 | 1516 | debug2("channel %d: input draining.", c->self); |
7368a6c8 | 1517 | c->type = SSH_CHANNEL_INPUT_DRAINING; |
1518 | } else { | |
1519 | chan_write_failed(c); | |
5260325f | 1520 | } |
7368a6c8 | 1521 | return -1; |
1522 | } | |
c1c6a032 | 1523 | if (compat20 && c->isatty && dlen >= 1 && buf[0] != '\r') { |
0ae4fe1d | 1524 | if (tcgetattr(c->wfd, &tio) == 0 && |
1525 | !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) { | |
1526 | /* | |
1527 | * Simulate echo to reduce the impact of | |
355724fc | 1528 | * traffic analysis. We need to match the |
95ce5599 | 1529 | * size of a SSH2_MSG_CHANNEL_DATA message |
c1c6a032 | 1530 | * (4 byte channel id + buf) |
0ae4fe1d | 1531 | */ |
95ce5599 | 1532 | packet_send_ignore(4 + len); |
0ae4fe1d | 1533 | packet_send(); |
0ae4fe1d | 1534 | } |
1535 | } | |
7368a6c8 | 1536 | buffer_consume(&c->output, len); |
7e7327a1 | 1537 | if (compat20 && len > 0) { |
1538 | c->local_consumed += len; | |
1539 | } | |
1540 | } | |
1541 | return 1; | |
1542 | } | |
396c147e | 1543 | static int |
7e7327a1 | 1544 | channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset) |
1545 | { | |
fa1d7d85 | 1546 | char buf[CHAN_RBUF]; |
7e7327a1 | 1547 | int len; |
1548 | ||
8ce64345 | 1549 | /** XXX handle drain efd, too */ |
7e7327a1 | 1550 | if (c->efd != -1) { |
1551 | if (c->extended_usage == CHAN_EXTENDED_WRITE && | |
1552 | FD_ISSET(c->efd, writeset) && | |
1553 | buffer_len(&c->extended) > 0) { | |
1554 | len = write(c->efd, buffer_ptr(&c->extended), | |
1555 | buffer_len(&c->extended)); | |
de273eef | 1556 | debug2("channel %d: written %d to efd %d", |
7e7327a1 | 1557 | c->self, len, c->efd); |
ee55dacf | 1558 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1559 | return 1; | |
1560 | if (len <= 0) { | |
1561 | debug2("channel %d: closing write-efd %d", | |
1562 | c->self, c->efd); | |
489aa2e9 | 1563 | channel_close_fd(&c->efd); |
ee55dacf | 1564 | } else { |
7e7327a1 | 1565 | buffer_consume(&c->extended, len); |
1566 | c->local_consumed += len; | |
1567 | } | |
1568 | } else if (c->extended_usage == CHAN_EXTENDED_READ && | |
1569 | FD_ISSET(c->efd, readset)) { | |
1570 | len = read(c->efd, buf, sizeof(buf)); | |
de273eef | 1571 | debug2("channel %d: read %d from efd %d", |
184eed6a | 1572 | c->self, len, c->efd); |
ee55dacf | 1573 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1574 | return 1; | |
1575 | if (len <= 0) { | |
1576 | debug2("channel %d: closing read-efd %d", | |
8ce64345 | 1577 | c->self, c->efd); |
489aa2e9 | 1578 | channel_close_fd(&c->efd); |
ee55dacf | 1579 | } else { |
7e7327a1 | 1580 | buffer_append(&c->extended, buf, len); |
ee55dacf | 1581 | } |
7e7327a1 | 1582 | } |
1583 | } | |
1584 | return 1; | |
1585 | } | |
396c147e | 1586 | static int |
5e96b616 | 1587 | channel_handle_ctl(Channel *c, fd_set * readset, fd_set * writeset) |
1588 | { | |
1589 | char buf[16]; | |
1590 | int len; | |
1591 | ||
1592 | /* Monitor control fd to detect if the slave client exits */ | |
1593 | if (c->ctl_fd != -1 && FD_ISSET(c->ctl_fd, readset)) { | |
1594 | len = read(c->ctl_fd, buf, sizeof(buf)); | |
1595 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) | |
1596 | return 1; | |
1597 | if (len <= 0) { | |
1598 | debug2("channel %d: ctl read<=0", c->self); | |
1599 | if (c->type != SSH_CHANNEL_OPEN) { | |
1600 | debug2("channel %d: not open", c->self); | |
1601 | chan_mark_dead(c); | |
1602 | return -1; | |
1603 | } else { | |
1604 | chan_read_failed(c); | |
1605 | chan_write_failed(c); | |
1606 | } | |
1607 | return -1; | |
1608 | } else | |
1609 | fatal("%s: unexpected data on ctl fd", __func__); | |
1610 | } | |
1611 | return 1; | |
1612 | } | |
1613 | static int | |
ee55dacf | 1614 | channel_check_window(Channel *c) |
7e7327a1 | 1615 | { |
28b9cb4d | 1616 | if (c->type == SSH_CHANNEL_OPEN && |
1617 | !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) && | |
7e7327a1 | 1618 | c->local_window < c->local_window_max/2 && |
1619 | c->local_consumed > 0) { | |
1620 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); | |
1621 | packet_put_int(c->remote_id); | |
1622 | packet_put_int(c->local_consumed); | |
1623 | packet_send(); | |
de273eef | 1624 | debug2("channel %d: window %d sent adjust %d", |
7e7327a1 | 1625 | c->self, c->local_window, |
1626 | c->local_consumed); | |
1627 | c->local_window += c->local_consumed; | |
1628 | c->local_consumed = 0; | |
7368a6c8 | 1629 | } |
1630 | return 1; | |
1631 | } | |
5260325f | 1632 | |
396c147e | 1633 | static void |
0c0738d5 | 1634 | channel_post_open(Channel *c, fd_set * readset, fd_set * writeset) |
7368a6c8 | 1635 | { |
639cb8ab | 1636 | if (c->delayed) |
1637 | return; | |
7368a6c8 | 1638 | channel_handle_rfd(c, readset, writeset); |
1639 | channel_handle_wfd(c, readset, writeset); | |
0c0738d5 | 1640 | if (!compat20) |
639cb8ab | 1641 | return; |
7e7327a1 | 1642 | channel_handle_efd(c, readset, writeset); |
5e96b616 | 1643 | channel_handle_ctl(c, readset, writeset); |
ee55dacf | 1644 | channel_check_window(c); |
7e7327a1 | 1645 | } |
1646 | ||
396c147e | 1647 | static void |
7368a6c8 | 1648 | channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset) |
1649 | { | |
1650 | int len; | |
e1feb9bf | 1651 | |
7368a6c8 | 1652 | /* Send buffered output data to the socket. */ |
1653 | if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) { | |
1654 | len = write(c->sock, buffer_ptr(&c->output), | |
1655 | buffer_len(&c->output)); | |
1656 | if (len <= 0) | |
9c50edcf | 1657 | buffer_clear(&c->output); |
7368a6c8 | 1658 | else |
1659 | buffer_consume(&c->output, len); | |
1660 | } | |
1661 | } | |
5260325f | 1662 | |
396c147e | 1663 | static void |
7e7327a1 | 1664 | channel_handler_init_20(void) |
1665 | { | |
0c0738d5 | 1666 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open; |
0b242b12 | 1667 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; |
7e7327a1 | 1668 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; |
fa08c86b | 1669 | channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener; |
0b242b12 | 1670 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; |
fa08c86b | 1671 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; |
97fb6912 | 1672 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1673 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7e7327a1 | 1674 | |
0c0738d5 | 1675 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open; |
7e7327a1 | 1676 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; |
fa08c86b | 1677 | channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener; |
0b242b12 | 1678 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; |
fa08c86b | 1679 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; |
97fb6912 | 1680 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
0c0738d5 | 1681 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open; |
7e7327a1 | 1682 | } |
1683 | ||
396c147e | 1684 | static void |
7368a6c8 | 1685 | channel_handler_init_13(void) |
1686 | { | |
1687 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13; | |
1688 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13; | |
1689 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; | |
1690 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; | |
1691 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; | |
1692 | channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining; | |
1693 | channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining; | |
97fb6912 | 1694 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1695 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7368a6c8 | 1696 | |
0c0738d5 | 1697 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open; |
7368a6c8 | 1698 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; |
1699 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
1700 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; | |
1701 | channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13; | |
97fb6912 | 1702 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
0c0738d5 | 1703 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open; |
7368a6c8 | 1704 | } |
5260325f | 1705 | |
396c147e | 1706 | static void |
7368a6c8 | 1707 | channel_handler_init_15(void) |
1708 | { | |
0c0738d5 | 1709 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open; |
0b242b12 | 1710 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; |
7368a6c8 | 1711 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; |
1712 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; | |
1713 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; | |
97fb6912 | 1714 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1715 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7368a6c8 | 1716 | |
1717 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; | |
1718 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
1719 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; | |
0c0738d5 | 1720 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open; |
97fb6912 | 1721 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
0c0738d5 | 1722 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open; |
7368a6c8 | 1723 | } |
1724 | ||
396c147e | 1725 | static void |
7368a6c8 | 1726 | channel_handler_init(void) |
1727 | { | |
1728 | int i; | |
e1feb9bf | 1729 | |
184eed6a | 1730 | for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) { |
7368a6c8 | 1731 | channel_pre[i] = NULL; |
1732 | channel_post[i] = NULL; | |
1733 | } | |
7e7327a1 | 1734 | if (compat20) |
1735 | channel_handler_init_20(); | |
1736 | else if (compat13) | |
7368a6c8 | 1737 | channel_handler_init_13(); |
1738 | else | |
1739 | channel_handler_init_15(); | |
1740 | } | |
1741 | ||
418e724c | 1742 | /* gc dead channels */ |
1743 | static void | |
1744 | channel_garbage_collect(Channel *c) | |
1745 | { | |
1746 | if (c == NULL) | |
1747 | return; | |
1748 | if (c->detach_user != NULL) { | |
8cd0437d | 1749 | if (!chan_is_dead(c, c->detach_close)) |
418e724c | 1750 | return; |
d7ac5f18 | 1751 | debug2("channel %d: gc: notify user", c->self); |
418e724c | 1752 | c->detach_user(c->self, NULL); |
1753 | /* if we still have a callback */ | |
1754 | if (c->detach_user != NULL) | |
1755 | return; | |
d7ac5f18 | 1756 | debug2("channel %d: gc: user detached", c->self); |
418e724c | 1757 | } |
1758 | if (!chan_is_dead(c, 1)) | |
1759 | return; | |
d7ac5f18 | 1760 | debug2("channel %d: garbage collecting", c->self); |
418e724c | 1761 | channel_free(c); |
1762 | } | |
1763 | ||
396c147e | 1764 | static void |
7368a6c8 | 1765 | channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset) |
1766 | { | |
1767 | static int did_init = 0; | |
9a995072 | 1768 | u_int i; |
7368a6c8 | 1769 | Channel *c; |
1770 | ||
1771 | if (!did_init) { | |
1772 | channel_handler_init(); | |
1773 | did_init = 1; | |
1774 | } | |
1775 | for (i = 0; i < channels_alloc; i++) { | |
719fc62f | 1776 | c = channels[i]; |
1777 | if (c == NULL) | |
5260325f | 1778 | continue; |
6fd8622b | 1779 | if (ftab[c->type] != NULL) |
1780 | (*ftab[c->type])(c, readset, writeset); | |
418e724c | 1781 | channel_garbage_collect(c); |
8efc0c15 | 1782 | } |
8efc0c15 | 1783 | } |
1784 | ||
8e7895b8 | 1785 | /* |
1786 | * Allocate/update select bitmasks and add any bits relevant to channels in | |
1787 | * select bitmasks. | |
1788 | */ | |
6ae2364d | 1789 | void |
c422989b | 1790 | channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp, |
9a995072 | 1791 | u_int *nallocp, int rekeying) |
7368a6c8 | 1792 | { |
9a995072 | 1793 | u_int n, sz; |
39929cdb | 1794 | |
1795 | n = MAX(*maxfdp, channel_max_fd); | |
1796 | ||
1797 | sz = howmany(n+1, NFDBITS) * sizeof(fd_mask); | |
489aa2e9 | 1798 | /* perhaps check sz < nalloc/2 and shrink? */ |
1799 | if (*readsetp == NULL || sz > *nallocp) { | |
1800 | *readsetp = xrealloc(*readsetp, sz); | |
1801 | *writesetp = xrealloc(*writesetp, sz); | |
1802 | *nallocp = sz; | |
39929cdb | 1803 | } |
489aa2e9 | 1804 | *maxfdp = n; |
39929cdb | 1805 | memset(*readsetp, 0, sz); |
1806 | memset(*writesetp, 0, sz); | |
1807 | ||
c422989b | 1808 | if (!rekeying) |
1809 | channel_handler(channel_pre, *readsetp, *writesetp); | |
7368a6c8 | 1810 | } |
1811 | ||
8e7895b8 | 1812 | /* |
1813 | * After select, perform any appropriate operations for channels which have | |
1814 | * events pending. | |
1815 | */ | |
6ae2364d | 1816 | void |
7368a6c8 | 1817 | channel_after_select(fd_set * readset, fd_set * writeset) |
1818 | { | |
1819 | channel_handler(channel_post, readset, writeset); | |
1820 | } | |
1821 | ||
8e7895b8 | 1822 | |
39929cdb | 1823 | /* If there is data to send to the connection, enqueue some of it now. */ |
8efc0c15 | 1824 | |
6ae2364d | 1825 | void |
d5bb9418 | 1826 | channel_output_poll(void) |
8efc0c15 | 1827 | { |
7368a6c8 | 1828 | Channel *c; |
9a995072 | 1829 | u_int i, len; |
5260325f | 1830 | |
1831 | for (i = 0; i < channels_alloc; i++) { | |
719fc62f | 1832 | c = channels[i]; |
1833 | if (c == NULL) | |
1834 | continue; | |
48e671d5 | 1835 | |
8e7895b8 | 1836 | /* |
1837 | * We are only interested in channels that can have buffered | |
1838 | * incoming data. | |
1839 | */ | |
48e671d5 | 1840 | if (compat13) { |
7368a6c8 | 1841 | if (c->type != SSH_CHANNEL_OPEN && |
1842 | c->type != SSH_CHANNEL_INPUT_DRAINING) | |
48e671d5 | 1843 | continue; |
1844 | } else { | |
7368a6c8 | 1845 | if (c->type != SSH_CHANNEL_OPEN) |
48e671d5 | 1846 | continue; |
48e671d5 | 1847 | } |
e78a59f5 | 1848 | if (compat20 && |
1849 | (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) { | |
ee55dacf | 1850 | /* XXX is this true? */ |
418e724c | 1851 | debug3("channel %d: will not send data after close", c->self); |
7e7327a1 | 1852 | continue; |
1853 | } | |
5260325f | 1854 | |
1855 | /* Get the amount of buffered data for this channel. */ | |
ee55dacf | 1856 | if ((c->istate == CHAN_INPUT_OPEN || |
1857 | c->istate == CHAN_INPUT_WAIT_DRAIN) && | |
1858 | (len = buffer_len(&c->input)) > 0) { | |
d20f3c9e | 1859 | if (c->datagram) { |
1860 | if (len > 0) { | |
1861 | u_char *data; | |
1862 | u_int dlen; | |
1863 | ||
1864 | data = buffer_get_string(&c->input, | |
1865 | &dlen); | |
1866 | packet_start(SSH2_MSG_CHANNEL_DATA); | |
1867 | packet_put_int(c->remote_id); | |
1868 | packet_put_string(data, dlen); | |
1869 | packet_send(); | |
1870 | c->remote_window -= dlen + 4; | |
1871 | xfree(data); | |
1872 | } | |
1873 | continue; | |
1874 | } | |
8e7895b8 | 1875 | /* |
1876 | * Send some data for the other side over the secure | |
1877 | * connection. | |
1878 | */ | |
7e7327a1 | 1879 | if (compat20) { |
1880 | if (len > c->remote_window) | |
1881 | len = c->remote_window; | |
1882 | if (len > c->remote_maxpacket) | |
1883 | len = c->remote_maxpacket; | |
5260325f | 1884 | } else { |
7e7327a1 | 1885 | if (packet_is_interactive()) { |
1886 | if (len > 1024) | |
1887 | len = 512; | |
1888 | } else { | |
1889 | /* Keep the packets at reasonable size. */ | |
1890 | if (len > packet_get_maxsize()/2) | |
1891 | len = packet_get_maxsize()/2; | |
1892 | } | |
5260325f | 1893 | } |
7368a6c8 | 1894 | if (len > 0) { |
7e7327a1 | 1895 | packet_start(compat20 ? |
1896 | SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA); | |
7368a6c8 | 1897 | packet_put_int(c->remote_id); |
1898 | packet_put_string(buffer_ptr(&c->input), len); | |
1899 | packet_send(); | |
1900 | buffer_consume(&c->input, len); | |
1901 | c->remote_window -= len; | |
7368a6c8 | 1902 | } |
1903 | } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) { | |
5260325f | 1904 | if (compat13) |
1905 | fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3"); | |
aa3378df | 1906 | /* |
1907 | * input-buffer is empty and read-socket shutdown: | |
d2296ed7 | 1908 | * tell peer, that we will not send more data: send IEOF. |
1909 | * hack for extended data: delay EOF if EFD still in use. | |
aa3378df | 1910 | */ |
d2296ed7 | 1911 | if (CHANNEL_EFD_INPUT_ACTIVE(c)) |
4e2e5cfd | 1912 | debug2("channel %d: ibuf_empty delayed efd %d/(%d)", |
1913 | c->self, c->efd, buffer_len(&c->extended)); | |
d2296ed7 | 1914 | else |
1915 | chan_ibuf_empty(c); | |
5260325f | 1916 | } |
7e7327a1 | 1917 | /* Send extended data, i.e. stderr */ |
1918 | if (compat20 && | |
d2296ed7 | 1919 | !(c->flags & CHAN_EOF_SENT) && |
7e7327a1 | 1920 | c->remote_window > 0 && |
1921 | (len = buffer_len(&c->extended)) > 0 && | |
1922 | c->extended_usage == CHAN_EXTENDED_READ) { | |
f91d9a89 | 1923 | debug2("channel %d: rwin %u elen %u euse %d", |
ee55dacf | 1924 | c->self, c->remote_window, buffer_len(&c->extended), |
1925 | c->extended_usage); | |
7e7327a1 | 1926 | if (len > c->remote_window) |
1927 | len = c->remote_window; | |
1928 | if (len > c->remote_maxpacket) | |
1929 | len = c->remote_maxpacket; | |
1930 | packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA); | |
1931 | packet_put_int(c->remote_id); | |
1932 | packet_put_int(SSH2_EXTENDED_DATA_STDERR); | |
1933 | packet_put_string(buffer_ptr(&c->extended), len); | |
1934 | packet_send(); | |
1935 | buffer_consume(&c->extended, len); | |
1936 | c->remote_window -= len; | |
ee55dacf | 1937 | debug2("channel %d: sent ext data %d", c->self, len); |
7e7327a1 | 1938 | } |
8efc0c15 | 1939 | } |
8efc0c15 | 1940 | } |
1941 | ||
8e7895b8 | 1942 | |
1943 | /* -- protocol input */ | |
8efc0c15 | 1944 | |
6ae2364d | 1945 | void |
7819b5c3 | 1946 | channel_input_data(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 1947 | { |
48e671d5 | 1948 | int id; |
5260325f | 1949 | char *data; |
1e3b8b07 | 1950 | u_int data_len; |
7368a6c8 | 1951 | Channel *c; |
5260325f | 1952 | |
1953 | /* Get the channel number and verify it. */ | |
48e671d5 | 1954 | id = packet_get_int(); |
7368a6c8 | 1955 | c = channel_lookup(id); |
1956 | if (c == NULL) | |
48e671d5 | 1957 | packet_disconnect("Received data for nonexistent channel %d.", id); |
5260325f | 1958 | |
1959 | /* Ignore any data for non-open channels (might happen on close) */ | |
7368a6c8 | 1960 | if (c->type != SSH_CHANNEL_OPEN && |
1961 | c->type != SSH_CHANNEL_X11_OPEN) | |
48e671d5 | 1962 | return; |
1963 | ||
5260325f | 1964 | /* Get the data. */ |
1965 | data = packet_get_string(&data_len); | |
7368a6c8 | 1966 | |
7741e239 | 1967 | /* |
1968 | * Ignore data for protocol > 1.3 if output end is no longer open. | |
1969 | * For protocol 2 the sending side is reducing its window as it sends | |
1970 | * data, so we must 'fake' consumption of the data in order to ensure | |
1971 | * that window updates are sent back. Otherwise the connection might | |
1972 | * deadlock. | |
1973 | */ | |
1974 | if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) { | |
1975 | if (compat20) { | |
1976 | c->local_window -= data_len; | |
1977 | c->local_consumed += data_len; | |
1978 | } | |
1979 | xfree(data); | |
1980 | return; | |
1981 | } | |
1982 | ||
6aacefa7 | 1983 | if (compat20) { |
7e7327a1 | 1984 | if (data_len > c->local_maxpacket) { |
bbe88b6d | 1985 | logit("channel %d: rcvd big packet %d, maxpack %d", |
7e7327a1 | 1986 | c->self, data_len, c->local_maxpacket); |
1987 | } | |
1988 | if (data_len > c->local_window) { | |
bbe88b6d | 1989 | logit("channel %d: rcvd too much data %d, win %d", |
7e7327a1 | 1990 | c->self, data_len, c->local_window); |
1991 | xfree(data); | |
1992 | return; | |
1993 | } | |
1994 | c->local_window -= data_len; | |
7e7327a1 | 1995 | } |
95500969 | 1996 | packet_check_eom(); |
d20f3c9e | 1997 | if (c->datagram) |
1998 | buffer_put_string(&c->output, data, data_len); | |
1999 | else | |
2000 | buffer_append(&c->output, data, data_len); | |
5260325f | 2001 | xfree(data); |
8efc0c15 | 2002 | } |
8e7895b8 | 2003 | |
6ae2364d | 2004 | void |
7819b5c3 | 2005 | channel_input_extended_data(int type, u_int32_t seq, void *ctxt) |
7e7327a1 | 2006 | { |
2007 | int id; | |
7e7327a1 | 2008 | char *data; |
a594fa74 | 2009 | u_int data_len, tcode; |
7e7327a1 | 2010 | Channel *c; |
2011 | ||
2012 | /* Get the channel number and verify it. */ | |
2013 | id = packet_get_int(); | |
2014 | c = channel_lookup(id); | |
2015 | ||
2016 | if (c == NULL) | |
2017 | packet_disconnect("Received extended_data for bad channel %d.", id); | |
2018 | if (c->type != SSH_CHANNEL_OPEN) { | |
bbe88b6d | 2019 | logit("channel %d: ext data for non open", id); |
7e7327a1 | 2020 | return; |
2021 | } | |
d2296ed7 | 2022 | if (c->flags & CHAN_EOF_RCVD) { |
2023 | if (datafellows & SSH_BUG_EXTEOF) | |
2024 | debug("channel %d: accepting ext data after eof", id); | |
2025 | else | |
2026 | packet_disconnect("Received extended_data after EOF " | |
2027 | "on channel %d.", id); | |
2028 | } | |
7e7327a1 | 2029 | tcode = packet_get_int(); |
2030 | if (c->efd == -1 || | |
2031 | c->extended_usage != CHAN_EXTENDED_WRITE || | |
2032 | tcode != SSH2_EXTENDED_DATA_STDERR) { | |
bbe88b6d | 2033 | logit("channel %d: bad ext data", c->self); |
7e7327a1 | 2034 | return; |
2035 | } | |
2036 | data = packet_get_string(&data_len); | |
95500969 | 2037 | packet_check_eom(); |
7e7327a1 | 2038 | if (data_len > c->local_window) { |
bbe88b6d | 2039 | logit("channel %d: rcvd too much extended_data %d, win %d", |
7e7327a1 | 2040 | c->self, data_len, c->local_window); |
2041 | xfree(data); | |
2042 | return; | |
2043 | } | |
de273eef | 2044 | debug2("channel %d: rcvd ext data %d", c->self, data_len); |
7e7327a1 | 2045 | c->local_window -= data_len; |
2046 | buffer_append(&c->extended, data, data_len); | |
2047 | xfree(data); | |
2048 | } | |
2049 | ||
6ae2364d | 2050 | void |
7819b5c3 | 2051 | channel_input_ieof(int type, u_int32_t seq, void *ctxt) |
7368a6c8 | 2052 | { |
2053 | int id; | |
2054 | Channel *c; | |
2055 | ||
7368a6c8 | 2056 | id = packet_get_int(); |
95500969 | 2057 | packet_check_eom(); |
7368a6c8 | 2058 | c = channel_lookup(id); |
2059 | if (c == NULL) | |
2060 | packet_disconnect("Received ieof for nonexistent channel %d.", id); | |
2061 | chan_rcvd_ieof(c); | |
a5f82435 | 2062 | |
2063 | /* XXX force input close */ | |
8341f420 | 2064 | if (c->force_drain && c->istate == CHAN_INPUT_OPEN) { |
a5f82435 | 2065 | debug("channel %d: FORCE input drain", c->self); |
2066 | c->istate = CHAN_INPUT_WAIT_DRAIN; | |
32e7d71f | 2067 | if (buffer_len(&c->input) == 0) |
2068 | chan_ibuf_empty(c); | |
a5f82435 | 2069 | } |
2070 | ||
7368a6c8 | 2071 | } |
8efc0c15 | 2072 | |
6ae2364d | 2073 | void |
7819b5c3 | 2074 | channel_input_close(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 2075 | { |
7368a6c8 | 2076 | int id; |
2077 | Channel *c; | |
5260325f | 2078 | |
7368a6c8 | 2079 | id = packet_get_int(); |
95500969 | 2080 | packet_check_eom(); |
7368a6c8 | 2081 | c = channel_lookup(id); |
2082 | if (c == NULL) | |
2083 | packet_disconnect("Received close for nonexistent channel %d.", id); | |
aa3378df | 2084 | |
2085 | /* | |
2086 | * Send a confirmation that we have closed the channel and no more | |
2087 | * data is coming for it. | |
2088 | */ | |
5260325f | 2089 | packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION); |
7368a6c8 | 2090 | packet_put_int(c->remote_id); |
5260325f | 2091 | packet_send(); |
2092 | ||
aa3378df | 2093 | /* |
2094 | * If the channel is in closed state, we have sent a close request, | |
2095 | * and the other side will eventually respond with a confirmation. | |
2096 | * Thus, we cannot free the channel here, because then there would be | |
2097 | * no-one to receive the confirmation. The channel gets freed when | |
2098 | * the confirmation arrives. | |
2099 | */ | |
7368a6c8 | 2100 | if (c->type != SSH_CHANNEL_CLOSED) { |
aa3378df | 2101 | /* |
2102 | * Not a closed channel - mark it as draining, which will | |
2103 | * cause it to be freed later. | |
2104 | */ | |
9c50edcf | 2105 | buffer_clear(&c->input); |
7368a6c8 | 2106 | c->type = SSH_CHANNEL_OUTPUT_DRAINING; |
5260325f | 2107 | } |
8efc0c15 | 2108 | } |
2109 | ||
7368a6c8 | 2110 | /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */ |
6ae2364d | 2111 | void |
7819b5c3 | 2112 | channel_input_oclose(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 2113 | { |
7368a6c8 | 2114 | int id = packet_get_int(); |
2115 | Channel *c = channel_lookup(id); | |
a8a21a53 | 2116 | |
95500969 | 2117 | packet_check_eom(); |
7368a6c8 | 2118 | if (c == NULL) |
2119 | packet_disconnect("Received oclose for nonexistent channel %d.", id); | |
2120 | chan_rcvd_oclose(c); | |
8efc0c15 | 2121 | } |
2122 | ||
6ae2364d | 2123 | void |
7819b5c3 | 2124 | channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt) |
7368a6c8 | 2125 | { |
2126 | int id = packet_get_int(); | |
2127 | Channel *c = channel_lookup(id); | |
2128 | ||
95500969 | 2129 | packet_check_eom(); |
7368a6c8 | 2130 | if (c == NULL) |
2131 | packet_disconnect("Received close confirmation for " | |
2132 | "out-of-range channel %d.", id); | |
2133 | if (c->type != SSH_CHANNEL_CLOSED) | |
2134 | packet_disconnect("Received close confirmation for " | |
2135 | "non-closed channel %d (type %d).", id, c->type); | |
719fc62f | 2136 | channel_free(c); |
7368a6c8 | 2137 | } |
8efc0c15 | 2138 | |
6ae2364d | 2139 | void |
7819b5c3 | 2140 | channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 2141 | { |
7368a6c8 | 2142 | int id, remote_id; |
2143 | Channel *c; | |
5260325f | 2144 | |
7368a6c8 | 2145 | id = packet_get_int(); |
2146 | c = channel_lookup(id); | |
5260325f | 2147 | |
7368a6c8 | 2148 | if (c==NULL || c->type != SSH_CHANNEL_OPENING) |
2149 | packet_disconnect("Received open confirmation for " | |
2150 | "non-opening channel %d.", id); | |
2151 | remote_id = packet_get_int(); | |
aa3378df | 2152 | /* Record the remote channel number and mark that the channel is now open. */ |
7368a6c8 | 2153 | c->remote_id = remote_id; |
2154 | c->type = SSH_CHANNEL_OPEN; | |
7e7327a1 | 2155 | |
2156 | if (compat20) { | |
2157 | c->remote_window = packet_get_int(); | |
2158 | c->remote_maxpacket = packet_get_int(); | |
05ca0898 | 2159 | if (c->confirm) { |
de273eef | 2160 | debug2("callback start"); |
5e96b616 | 2161 | c->confirm(c->self, c->confirm_ctx); |
de273eef | 2162 | debug2("callback done"); |
7e7327a1 | 2163 | } |
d7ac5f18 | 2164 | debug2("channel %d: open confirm rwindow %u rmax %u", c->self, |
7e7327a1 | 2165 | c->remote_window, c->remote_maxpacket); |
2166 | } | |
95500969 | 2167 | packet_check_eom(); |
8efc0c15 | 2168 | } |
2169 | ||
396c147e | 2170 | static char * |
d18e0850 | 2171 | reason2txt(int reason) |
2172 | { | |
6aacefa7 | 2173 | switch (reason) { |
d18e0850 | 2174 | case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED: |
2175 | return "administratively prohibited"; | |
2176 | case SSH2_OPEN_CONNECT_FAILED: | |
2177 | return "connect failed"; | |
2178 | case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE: | |
2179 | return "unknown channel type"; | |
2180 | case SSH2_OPEN_RESOURCE_SHORTAGE: | |
2181 | return "resource shortage"; | |
2182 | } | |
7e8c18e9 | 2183 | return "unknown reason"; |
d18e0850 | 2184 | } |
2185 | ||
6ae2364d | 2186 | void |
7819b5c3 | 2187 | channel_input_open_failure(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 2188 | { |
02a024dd | 2189 | int id, reason; |
2190 | char *msg = NULL, *lang = NULL; | |
7368a6c8 | 2191 | Channel *c; |
5260325f | 2192 | |
7368a6c8 | 2193 | id = packet_get_int(); |
2194 | c = channel_lookup(id); | |
2195 | ||
2196 | if (c==NULL || c->type != SSH_CHANNEL_OPENING) | |
2197 | packet_disconnect("Received open failure for " | |
2198 | "non-opening channel %d.", id); | |
7e7327a1 | 2199 | if (compat20) { |
02a024dd | 2200 | reason = packet_get_int(); |
fbe90f7b | 2201 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { |
02a024dd | 2202 | msg = packet_get_string(NULL); |
2203 | lang = packet_get_string(NULL); | |
2204 | } | |
bbe88b6d | 2205 | logit("channel %d: open failed: %s%s%s", id, |
d18e0850 | 2206 | reason2txt(reason), msg ? ": ": "", msg ? msg : ""); |
02a024dd | 2207 | if (msg != NULL) |
2208 | xfree(msg); | |
2209 | if (lang != NULL) | |
2210 | xfree(lang); | |
7e7327a1 | 2211 | } |
95500969 | 2212 | packet_check_eom(); |
5260325f | 2213 | /* Free the channel. This will also close the socket. */ |
719fc62f | 2214 | channel_free(c); |
8efc0c15 | 2215 | } |
2216 | ||
8e7895b8 | 2217 | void |
7819b5c3 | 2218 | channel_input_window_adjust(int type, u_int32_t seq, void *ctxt) |
8e7895b8 | 2219 | { |
2220 | Channel *c; | |
f91d9a89 | 2221 | int id; |
2222 | u_int adjust; | |
3ffc6336 | 2223 | |
8e7895b8 | 2224 | if (!compat20) |
2225 | return; | |
8efc0c15 | 2226 | |
8e7895b8 | 2227 | /* Get the channel number and verify it. */ |
2228 | id = packet_get_int(); | |
2229 | c = channel_lookup(id); | |
2230 | ||
b872f7f0 | 2231 | if (c == NULL) { |
2232 | logit("Received window adjust for non-open channel %d.", id); | |
8e7895b8 | 2233 | return; |
2234 | } | |
2235 | adjust = packet_get_int(); | |
95500969 | 2236 | packet_check_eom(); |
f91d9a89 | 2237 | debug2("channel %d: rcvd adjust %u", id, adjust); |
8e7895b8 | 2238 | c->remote_window += adjust; |
2239 | } | |
2240 | ||
2241 | void | |
7819b5c3 | 2242 | channel_input_port_open(int type, u_int32_t seq, void *ctxt) |
8efc0c15 | 2243 | { |
8e7895b8 | 2244 | Channel *c = NULL; |
2245 | u_short host_port; | |
2246 | char *host, *originator_string; | |
2247 | int remote_id, sock = -1; | |
5260325f | 2248 | |
8e7895b8 | 2249 | remote_id = packet_get_int(); |
2250 | host = packet_get_string(NULL); | |
2251 | host_port = packet_get_int(); | |
2252 | ||
2253 | if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) { | |
2254 | originator_string = packet_get_string(NULL); | |
2255 | } else { | |
2256 | originator_string = xstrdup("unknown (remote did not supply name)"); | |
2257 | } | |
95500969 | 2258 | packet_check_eom(); |
8e7895b8 | 2259 | sock = channel_connect_to(host, host_port); |
2260 | if (sock != -1) { | |
2261 | c = channel_new("connected socket", | |
2262 | SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0, | |
2263 | originator_string, 1); | |
3a0d3d54 | 2264 | c->remote_id = remote_id; |
5260325f | 2265 | } |
0d942eff | 2266 | xfree(originator_string); |
8e7895b8 | 2267 | if (c == NULL) { |
2268 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
2269 | packet_put_int(remote_id); | |
2270 | packet_send(); | |
2271 | } | |
2272 | xfree(host); | |
8efc0c15 | 2273 | } |
2274 | ||
8e7895b8 | 2275 | |
2276 | /* -- tcp forwarding */ | |
2277 | ||
5e4a7219 | 2278 | void |
2279 | channel_set_af(int af) | |
2280 | { | |
2281 | IPv4or6 = af; | |
2282 | } | |
2283 | ||
5641aefa | 2284 | static int |
2285 | channel_setup_fwd_listener(int type, const char *listen_addr, u_short listen_port, | |
2286 | const char *host_to_connect, u_short port_to_connect, int gateway_ports) | |
8efc0c15 | 2287 | { |
719fc62f | 2288 | Channel *c; |
442aee3a | 2289 | int sock, r, success = 0, wildcard = 0, is_client; |
48e671d5 | 2290 | struct addrinfo hints, *ai, *aitop; |
3867aa0a | 2291 | const char *host, *addr; |
5641aefa | 2292 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; |
5260325f | 2293 | |
5641aefa | 2294 | host = (type == SSH_CHANNEL_RPORT_LISTENER) ? |
2295 | listen_addr : host_to_connect; | |
3867aa0a | 2296 | is_client = (type == SSH_CHANNEL_PORT_LISTENER); |
02a024dd | 2297 | |
5641aefa | 2298 | if (host == NULL) { |
2299 | error("No forward host name."); | |
38946c65 | 2300 | return 0; |
fa08c86b | 2301 | } |
719fc62f | 2302 | if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) { |
02a024dd | 2303 | error("Forward host name too long."); |
38946c65 | 2304 | return 0; |
02a024dd | 2305 | } |
5260325f | 2306 | |
3867aa0a | 2307 | /* |
2308 | * Determine whether or not a port forward listens to loopback, | |
f8cc7664 | 2309 | * specified address or wildcard. On the client, a specified bind |
2310 | * address will always override gateway_ports. On the server, a | |
2311 | * gateway_ports of 1 (``yes'') will override the client's | |
2312 | * specification and force a wildcard bind, whereas a value of 2 | |
2313 | * (``clientspecified'') will bind to whatever address the client | |
3867aa0a | 2314 | * asked for. |
2315 | * | |
2316 | * Special-case listen_addrs are: | |
2317 | * | |
2318 | * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR | |
2319 | * "" (empty string), "*" -> wildcard v4/v6 | |
2320 | * "localhost" -> loopback v4/v6 | |
2321 | */ | |
2322 | addr = NULL; | |
2323 | if (listen_addr == NULL) { | |
2324 | /* No address specified: default to gateway_ports setting */ | |
2325 | if (gateway_ports) | |
2326 | wildcard = 1; | |
2327 | } else if (gateway_ports || is_client) { | |
2328 | if (((datafellows & SSH_OLD_FORWARD_ADDR) && | |
2329 | strcmp(listen_addr, "0.0.0.0") == 0) || | |
2330 | *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 || | |
2331 | (!is_client && gateway_ports == 1)) | |
2332 | wildcard = 1; | |
2333 | else if (strcmp(listen_addr, "localhost") != 0) | |
2334 | addr = listen_addr; | |
2335 | } | |
2336 | ||
2337 | debug3("channel_setup_fwd_listener: type %d wildcard %d addr %s", | |
2338 | type, wildcard, (addr == NULL) ? "NULL" : addr); | |
2339 | ||
aa3378df | 2340 | /* |
48e671d5 | 2341 | * getaddrinfo returns a loopback address if the hostname is |
2342 | * set to NULL and hints.ai_flags is not AI_PASSIVE | |
aa3378df | 2343 | */ |
48e671d5 | 2344 | memset(&hints, 0, sizeof(hints)); |
2345 | hints.ai_family = IPv4or6; | |
3867aa0a | 2346 | hints.ai_flags = wildcard ? AI_PASSIVE : 0; |
48e671d5 | 2347 | hints.ai_socktype = SOCK_STREAM; |
fa08c86b | 2348 | snprintf(strport, sizeof strport, "%d", listen_port); |
3867aa0a | 2349 | if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) { |
2350 | if (addr == NULL) { | |
2351 | /* This really shouldn't happen */ | |
2352 | packet_disconnect("getaddrinfo: fatal error: %s", | |
2353 | gai_strerror(r)); | |
2354 | } else { | |
38946c65 | 2355 | error("channel_setup_fwd_listener: " |
3867aa0a | 2356 | "getaddrinfo(%.64s): %s", addr, gai_strerror(r)); |
2357 | } | |
38946c65 | 2358 | return 0; |
3867aa0a | 2359 | } |
48e671d5 | 2360 | |
48e671d5 | 2361 | for (ai = aitop; ai; ai = ai->ai_next) { |
2362 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2363 | continue; | |
2364 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), | |
2365 | strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
5641aefa | 2366 | error("channel_setup_fwd_listener: getnameinfo failed"); |
48e671d5 | 2367 | continue; |
2368 | } | |
2369 | /* Create a port to listen for the host. */ | |
3e131a6d | 2370 | sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); |
48e671d5 | 2371 | if (sock < 0) { |
2372 | /* this is no error since kernel may not support ipv6 */ | |
2373 | verbose("socket: %.100s", strerror(errno)); | |
2374 | continue; | |
2375 | } | |
442aee3a | 2376 | |
2377 | channel_set_reuseaddr(sock); | |
facfd613 | 2378 | |
48e671d5 | 2379 | debug("Local forwarding listening on %s port %s.", ntop, strport); |
2380 | ||
2381 | /* Bind the socket to the address. */ | |
2382 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
2383 | /* address can be in use ipv6 address is already bound */ | |
16218745 | 2384 | if (!ai->ai_next) |
2385 | error("bind: %.100s", strerror(errno)); | |
2386 | else | |
2387 | verbose("bind: %.100s", strerror(errno)); | |
2b87da3b | 2388 | |
48e671d5 | 2389 | close(sock); |
2390 | continue; | |
2391 | } | |
2392 | /* Start listening for connections on the socket. */ | |
fce39749 | 2393 | if (listen(sock, SSH_LISTEN_BACKLOG) < 0) { |
48e671d5 | 2394 | error("listen: %.100s", strerror(errno)); |
2395 | close(sock); | |
2396 | continue; | |
2397 | } | |
2398 | /* Allocate a channel number for the socket. */ | |
8e7895b8 | 2399 | c = channel_new("port listener", type, sock, sock, -1, |
0b242b12 | 2400 | CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, |
0d942eff | 2401 | 0, "port listener", 1); |
719fc62f | 2402 | strlcpy(c->path, host, sizeof(c->path)); |
2403 | c->host_port = port_to_connect; | |
2404 | c->listening_port = listen_port; | |
48e671d5 | 2405 | success = 1; |
2406 | } | |
2407 | if (success == 0) | |
5641aefa | 2408 | error("channel_setup_fwd_listener: cannot listen to port: %d", |
02a024dd | 2409 | listen_port); |
48e671d5 | 2410 | freeaddrinfo(aitop); |
02a024dd | 2411 | return success; |
5260325f | 2412 | } |
8efc0c15 | 2413 | |
d740ec16 | 2414 | int |
2415 | channel_cancel_rport_listener(const char *host, u_short port) | |
2416 | { | |
9a995072 | 2417 | u_int i; |
2418 | int found = 0; | |
d740ec16 | 2419 | |
f8cc7664 | 2420 | for (i = 0; i < channels_alloc; i++) { |
d740ec16 | 2421 | Channel *c = channels[i]; |
2422 | ||
2423 | if (c != NULL && c->type == SSH_CHANNEL_RPORT_LISTENER && | |
2424 | strncmp(c->path, host, sizeof(c->path)) == 0 && | |
f2107e97 | 2425 | c->listening_port == port) { |
2912cbd6 | 2426 | debug2("%s: close channel %d", __func__, i); |
d740ec16 | 2427 | channel_free(c); |
2428 | found = 1; | |
2429 | } | |
2430 | } | |
2431 | ||
2432 | return (found); | |
2433 | } | |
2434 | ||
5641aefa | 2435 | /* protocol local port fwd, used by ssh (and sshd in v1) */ |
2436 | int | |
3867aa0a | 2437 | channel_setup_local_fwd_listener(const char *listen_host, u_short listen_port, |
5641aefa | 2438 | const char *host_to_connect, u_short port_to_connect, int gateway_ports) |
2439 | { | |
2440 | return channel_setup_fwd_listener(SSH_CHANNEL_PORT_LISTENER, | |
3867aa0a | 2441 | listen_host, listen_port, host_to_connect, port_to_connect, |
2442 | gateway_ports); | |
5641aefa | 2443 | } |
2444 | ||
2445 | /* protocol v2 remote port fwd, used by sshd */ | |
2446 | int | |
2447 | channel_setup_remote_fwd_listener(const char *listen_address, | |
2448 | u_short listen_port, int gateway_ports) | |
2449 | { | |
2450 | return channel_setup_fwd_listener(SSH_CHANNEL_RPORT_LISTENER, | |
2451 | listen_address, listen_port, NULL, 0, gateway_ports); | |
2452 | } | |
2453 | ||
aa3378df | 2454 | /* |
2455 | * Initiate forwarding of connections to port "port" on remote host through | |
2456 | * the secure channel to host:port from local side. | |
2457 | */ | |
8efc0c15 | 2458 | |
6ae2364d | 2459 | void |
3867aa0a | 2460 | channel_request_remote_forwarding(const char *listen_host, u_short listen_port, |
fa08c86b | 2461 | const char *host_to_connect, u_short port_to_connect) |
8efc0c15 | 2462 | { |
54a5250f | 2463 | int type, success = 0; |
fa08c86b | 2464 | |
5260325f | 2465 | /* Record locally that connection to this host/port is permitted. */ |
2466 | if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION) | |
2467 | fatal("channel_request_remote_forwarding: too many forwards"); | |
2468 | ||
5260325f | 2469 | /* Send the forward request to the remote side. */ |
7e7327a1 | 2470 | if (compat20) { |
3867aa0a | 2471 | const char *address_to_bind; |
2472 | if (listen_host == NULL) | |
2473 | address_to_bind = "localhost"; | |
2474 | else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) | |
2475 | address_to_bind = ""; | |
2476 | else | |
2477 | address_to_bind = listen_host; | |
2478 | ||
7e7327a1 | 2479 | packet_start(SSH2_MSG_GLOBAL_REQUEST); |
2480 | packet_put_cstring("tcpip-forward"); | |
e0ae8728 | 2481 | packet_put_char(1); /* boolean: want reply */ |
7e7327a1 | 2482 | packet_put_cstring(address_to_bind); |
2483 | packet_put_int(listen_port); | |
fa08c86b | 2484 | packet_send(); |
2485 | packet_write_wait(); | |
2486 | /* Assume that server accepts the request */ | |
2487 | success = 1; | |
7e7327a1 | 2488 | } else { |
2489 | packet_start(SSH_CMSG_PORT_FORWARD_REQUEST); | |
7e7327a1 | 2490 | packet_put_int(listen_port); |
d6f24e45 | 2491 | packet_put_cstring(host_to_connect); |
2492 | packet_put_int(port_to_connect); | |
7e7327a1 | 2493 | packet_send(); |
2494 | packet_write_wait(); | |
fa08c86b | 2495 | |
2496 | /* Wait for response from the remote side. */ | |
54a5250f | 2497 | type = packet_read(); |
fa08c86b | 2498 | switch (type) { |
2499 | case SSH_SMSG_SUCCESS: | |
2500 | success = 1; | |
2501 | break; | |
2502 | case SSH_SMSG_FAILURE: | |
bbe88b6d | 2503 | logit("Warning: Server denied remote port forwarding."); |
fa08c86b | 2504 | break; |
2505 | default: | |
2506 | /* Unknown packet */ | |
2507 | packet_disconnect("Protocol error for port forward request:" | |
2508 | "received packet type %d.", type); | |
2509 | } | |
2510 | } | |
2511 | if (success) { | |
2512 | permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect); | |
2513 | permitted_opens[num_permitted_opens].port_to_connect = port_to_connect; | |
2514 | permitted_opens[num_permitted_opens].listen_port = listen_port; | |
2515 | num_permitted_opens++; | |
7e7327a1 | 2516 | } |
8efc0c15 | 2517 | } |
2518 | ||
d740ec16 | 2519 | /* |
f2107e97 | 2520 | * Request cancellation of remote forwarding of connection host:port from |
d740ec16 | 2521 | * local side. |
2522 | */ | |
d740ec16 | 2523 | void |
3867aa0a | 2524 | channel_request_rforward_cancel(const char *host, u_short port) |
d740ec16 | 2525 | { |
2526 | int i; | |
d740ec16 | 2527 | |
2528 | if (!compat20) | |
2529 | return; | |
2530 | ||
2531 | for (i = 0; i < num_permitted_opens; i++) { | |
f2107e97 | 2532 | if (permitted_opens[i].host_to_connect != NULL && |
d740ec16 | 2533 | permitted_opens[i].listen_port == port) |
2534 | break; | |
2535 | } | |
2536 | if (i >= num_permitted_opens) { | |
2537 | debug("%s: requested forward not found", __func__); | |
2538 | return; | |
2539 | } | |
2540 | packet_start(SSH2_MSG_GLOBAL_REQUEST); | |
2541 | packet_put_cstring("cancel-tcpip-forward"); | |
2542 | packet_put_char(0); | |
3867aa0a | 2543 | packet_put_cstring(host == NULL ? "" : host); |
d740ec16 | 2544 | packet_put_int(port); |
2545 | packet_send(); | |
2546 | ||
2547 | permitted_opens[i].listen_port = 0; | |
2548 | permitted_opens[i].port_to_connect = 0; | |
8c4bd764 | 2549 | xfree(permitted_opens[i].host_to_connect); |
d740ec16 | 2550 | permitted_opens[i].host_to_connect = NULL; |
2551 | } | |
2552 | ||
aa3378df | 2553 | /* |
2554 | * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates | |
2555 | * listening for the port, and sends back a success reply (or disconnect | |
2556 | * message if there was an error). This never returns if there was an error. | |
2557 | */ | |
8efc0c15 | 2558 | |
6ae2364d | 2559 | void |
1d1ffb87 | 2560 | channel_input_port_forward_request(int is_root, int gateway_ports) |
8efc0c15 | 2561 | { |
57112b5a | 2562 | u_short port, host_port; |
5260325f | 2563 | char *hostname; |
2564 | ||
2565 | /* Get arguments from the packet. */ | |
2566 | port = packet_get_int(); | |
2567 | hostname = packet_get_string(NULL); | |
2568 | host_port = packet_get_int(); | |
2569 | ||
3c62e7eb | 2570 | #ifndef HAVE_CYGWIN |
aa3378df | 2571 | /* |
2572 | * Check that an unprivileged user is not trying to forward a | |
2573 | * privileged port. | |
2574 | */ | |
5260325f | 2575 | if (port < IPPORT_RESERVED && !is_root) |
8e7c9afc | 2576 | packet_disconnect( |
2577 | "Requested forwarding of port %d but user is not root.", | |
2578 | port); | |
2579 | if (host_port == 0) | |
2580 | packet_disconnect("Dynamic forwarding denied."); | |
3c62e7eb | 2581 | #endif |
8e7c9afc | 2582 | |
fa08c86b | 2583 | /* Initiate forwarding */ |
3867aa0a | 2584 | channel_setup_local_fwd_listener(NULL, port, hostname, |
2585 | host_port, gateway_ports); | |
5260325f | 2586 | |
2587 | /* Free the argument string. */ | |
2588 | xfree(hostname); | |
8efc0c15 | 2589 | } |
2590 | ||
01794848 | 2591 | /* |
2592 | * Permits opening to any host/port if permitted_opens[] is empty. This is | |
2593 | * usually called by the server, because the user could connect to any port | |
2594 | * anyway, and the server has no way to know but to trust the client anyway. | |
2595 | */ | |
2596 | void | |
d5bb9418 | 2597 | channel_permit_all_opens(void) |
01794848 | 2598 | { |
2599 | if (num_permitted_opens == 0) | |
2600 | all_opens_permitted = 1; | |
2601 | } | |
2602 | ||
cd332296 | 2603 | void |
01794848 | 2604 | channel_add_permitted_opens(char *host, int port) |
2605 | { | |
2606 | if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION) | |
2607 | fatal("channel_request_remote_forwarding: too many forwards"); | |
2608 | debug("allow port forwarding to host %s port %d", host, port); | |
2609 | ||
2610 | permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host); | |
2611 | permitted_opens[num_permitted_opens].port_to_connect = port; | |
2612 | num_permitted_opens++; | |
2613 | ||
2614 | all_opens_permitted = 0; | |
2615 | } | |
2616 | ||
cd332296 | 2617 | void |
01794848 | 2618 | channel_clear_permitted_opens(void) |
2619 | { | |
2620 | int i; | |
2621 | ||
2622 | for (i = 0; i < num_permitted_opens; i++) | |
d740ec16 | 2623 | if (permitted_opens[i].host_to_connect != NULL) |
2624 | xfree(permitted_opens[i].host_to_connect); | |
01794848 | 2625 | num_permitted_opens = 0; |
2626 | ||
2627 | } | |
2628 | ||
2629 | ||
2630 | /* return socket to remote host, port */ | |
396c147e | 2631 | static int |
01794848 | 2632 | connect_to(const char *host, u_short port) |
8efc0c15 | 2633 | { |
48e671d5 | 2634 | struct addrinfo hints, *ai, *aitop; |
2635 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; | |
2636 | int gaierr; | |
7368a6c8 | 2637 | int sock = -1; |
48e671d5 | 2638 | |
2639 | memset(&hints, 0, sizeof(hints)); | |
2640 | hints.ai_family = IPv4or6; | |
2641 | hints.ai_socktype = SOCK_STREAM; | |
01794848 | 2642 | snprintf(strport, sizeof strport, "%d", port); |
48e671d5 | 2643 | if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) { |
01794848 | 2644 | error("connect_to %.100s: unknown host (%s)", host, |
2645 | gai_strerror(gaierr)); | |
7368a6c8 | 2646 | return -1; |
48e671d5 | 2647 | } |
48e671d5 | 2648 | for (ai = aitop; ai; ai = ai->ai_next) { |
2649 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2650 | continue; | |
2651 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), | |
2652 | strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
01794848 | 2653 | error("connect_to: getnameinfo failed"); |
48e671d5 | 2654 | continue; |
5260325f | 2655 | } |
3e131a6d | 2656 | sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); |
48e671d5 | 2657 | if (sock < 0) { |
4940c411 | 2658 | if (ai->ai_next == NULL) |
2659 | error("socket: %.100s", strerror(errno)); | |
2660 | else | |
2661 | verbose("socket: %.100s", strerror(errno)); | |
48e671d5 | 2662 | continue; |
5260325f | 2663 | } |
170694d7 | 2664 | if (set_nonblock(sock) == -1) |
2665 | fatal("%s: set_nonblock(%d)", __func__, sock); | |
97fb6912 | 2666 | if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 && |
2667 | errno != EINPROGRESS) { | |
01794848 | 2668 | error("connect_to %.100s port %s: %.100s", ntop, strport, |
48e671d5 | 2669 | strerror(errno)); |
2670 | close(sock); | |
2b87da3b | 2671 | continue; /* fail -- try next */ |
48e671d5 | 2672 | } |
2673 | break; /* success */ | |
5260325f | 2674 | |
5260325f | 2675 | } |
48e671d5 | 2676 | freeaddrinfo(aitop); |
48e671d5 | 2677 | if (!ai) { |
01794848 | 2678 | error("connect_to %.100s port %d: failed.", host, port); |
7368a6c8 | 2679 | return -1; |
8efc0c15 | 2680 | } |
7368a6c8 | 2681 | /* success */ |
811a6342 | 2682 | set_nodelay(sock); |
7368a6c8 | 2683 | return sock; |
2684 | } | |
01794848 | 2685 | |
fa08c86b | 2686 | int |
b3f8a79c | 2687 | channel_connect_by_listen_address(u_short listen_port) |
fa08c86b | 2688 | { |
2689 | int i; | |
01794848 | 2690 | |
fa08c86b | 2691 | for (i = 0; i < num_permitted_opens; i++) |
d740ec16 | 2692 | if (permitted_opens[i].host_to_connect != NULL && |
2693 | permitted_opens[i].listen_port == listen_port) | |
01794848 | 2694 | return connect_to( |
fa08c86b | 2695 | permitted_opens[i].host_to_connect, |
2696 | permitted_opens[i].port_to_connect); | |
0b6fbf03 | 2697 | error("WARNING: Server requests forwarding for unknown listen_port %d", |
2698 | listen_port); | |
fa08c86b | 2699 | return -1; |
2700 | } | |
48e671d5 | 2701 | |
01794848 | 2702 | /* Check if connecting to that port is permitted and connect. */ |
2703 | int | |
2704 | channel_connect_to(const char *host, u_short port) | |
2705 | { | |
2706 | int i, permit; | |
2707 | ||
2708 | permit = all_opens_permitted; | |
2709 | if (!permit) { | |
2710 | for (i = 0; i < num_permitted_opens; i++) | |
d740ec16 | 2711 | if (permitted_opens[i].host_to_connect != NULL && |
2712 | permitted_opens[i].port_to_connect == port && | |
01794848 | 2713 | strcmp(permitted_opens[i].host_to_connect, host) == 0) |
2714 | permit = 1; | |
2715 | ||
2716 | } | |
2717 | if (!permit) { | |
bbe88b6d | 2718 | logit("Received request to connect to host %.100s port %d, " |
01794848 | 2719 | "but the request was denied.", host, port); |
2720 | return -1; | |
2721 | } | |
2722 | return connect_to(host, port); | |
2723 | } | |
2724 | ||
5e96b616 | 2725 | void |
2726 | channel_send_window_changes(void) | |
2727 | { | |
9a995072 | 2728 | u_int i; |
5e96b616 | 2729 | struct winsize ws; |
2730 | ||
2731 | for (i = 0; i < channels_alloc; i++) { | |
f8cc7664 | 2732 | if (channels[i] == NULL || !channels[i]->client_tty || |
5e96b616 | 2733 | channels[i]->type != SSH_CHANNEL_OPEN) |
2734 | continue; | |
2735 | if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0) | |
2736 | continue; | |
2737 | channel_request_start(i, "window-change", 0); | |
2738 | packet_put_int(ws.ws_col); | |
2739 | packet_put_int(ws.ws_row); | |
2740 | packet_put_int(ws.ws_xpixel); | |
2741 | packet_put_int(ws.ws_ypixel); | |
2742 | packet_send(); | |
2743 | } | |
2744 | } | |
2745 | ||
8e7895b8 | 2746 | /* -- X11 forwarding */ |
8efc0c15 | 2747 | |
aa3378df | 2748 | /* |
2749 | * Creates an internet domain socket for listening for X11 connections. | |
57f228e8 | 2750 | * Returns 0 and a suitable display number for the DISPLAY variable |
2751 | * stored in display_numberp , or -1 if an error occurs. | |
aa3378df | 2752 | */ |
c9d0ad9b | 2753 | int |
e6e573bd | 2754 | x11_create_display_inet(int x11_display_offset, int x11_use_localhost, |
d08341e6 | 2755 | int single_connection, u_int *display_numberp, int **chanids) |
8efc0c15 | 2756 | { |
ac151b18 | 2757 | Channel *nc = NULL; |
57112b5a | 2758 | int display_number, sock; |
2759 | u_short port; | |
48e671d5 | 2760 | struct addrinfo hints, *ai, *aitop; |
2761 | char strport[NI_MAXSERV]; | |
2762 | int gaierr, n, num_socks = 0, socks[NUM_SOCKS]; | |
5260325f | 2763 | |
59e5aff5 | 2764 | if (chanids == NULL) |
2765 | return -1; | |
2766 | ||
95f1eccc | 2767 | for (display_number = x11_display_offset; |
184eed6a | 2768 | display_number < MAX_DISPLAYS; |
2769 | display_number++) { | |
5260325f | 2770 | port = 6000 + display_number; |
48e671d5 | 2771 | memset(&hints, 0, sizeof(hints)); |
2772 | hints.ai_family = IPv4or6; | |
e6e573bd | 2773 | hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE; |
48e671d5 | 2774 | hints.ai_socktype = SOCK_STREAM; |
2775 | snprintf(strport, sizeof strport, "%d", port); | |
2776 | if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) { | |
2777 | error("getaddrinfo: %.100s", gai_strerror(gaierr)); | |
c9d0ad9b | 2778 | return -1; |
5260325f | 2779 | } |
48e671d5 | 2780 | for (ai = aitop; ai; ai = ai->ai_next) { |
2781 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2782 | continue; | |
3e131a6d | 2783 | sock = socket(ai->ai_family, ai->ai_socktype, |
2784 | ai->ai_protocol); | |
48e671d5 | 2785 | if (sock < 0) { |
4ee81249 | 2786 | if ((errno != EINVAL) && (errno != EAFNOSUPPORT)) { |
80a44451 | 2787 | error("socket: %.100s", strerror(errno)); |
0ea89f7e | 2788 | freeaddrinfo(aitop); |
c9d0ad9b | 2789 | return -1; |
80a44451 | 2790 | } else { |
22d89d24 | 2791 | debug("x11_create_display_inet: Socket family %d not supported", |
2792 | ai->ai_family); | |
80a44451 | 2793 | continue; |
2794 | } | |
48e671d5 | 2795 | } |
688aaeda | 2796 | #ifdef IPV6_V6ONLY |
2797 | if (ai->ai_family == AF_INET6) { | |
2798 | int on = 1; | |
2799 | if (setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) < 0) | |
2800 | error("setsockopt IPV6_V6ONLY: %.100s", strerror(errno)); | |
2801 | } | |
2802 | #endif | |
442aee3a | 2803 | channel_set_reuseaddr(sock); |
48e671d5 | 2804 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { |
d7ac5f18 | 2805 | debug2("bind port %d: %.100s", port, strerror(errno)); |
48e671d5 | 2806 | close(sock); |
16218745 | 2807 | |
2808 | if (ai->ai_next) | |
2809 | continue; | |
2810 | ||
48e671d5 | 2811 | for (n = 0; n < num_socks; n++) { |
48e671d5 | 2812 | close(socks[n]); |
2813 | } | |
2814 | num_socks = 0; | |
2815 | break; | |
2816 | } | |
2817 | socks[num_socks++] = sock; | |
80faa19f | 2818 | #ifndef DONT_TRY_OTHER_AF |
48e671d5 | 2819 | if (num_socks == NUM_SOCKS) |
2820 | break; | |
80faa19f | 2821 | #else |
688aaeda | 2822 | if (x11_use_localhost) { |
2823 | if (num_socks == NUM_SOCKS) | |
2824 | break; | |
2825 | } else { | |
2826 | break; | |
2827 | } | |
80faa19f | 2828 | #endif |
5260325f | 2829 | } |
4ccb01d6 | 2830 | freeaddrinfo(aitop); |
48e671d5 | 2831 | if (num_socks > 0) |
2832 | break; | |
5260325f | 2833 | } |
2834 | if (display_number >= MAX_DISPLAYS) { | |
2835 | error("Failed to allocate internet-domain X11 display socket."); | |
c9d0ad9b | 2836 | return -1; |
8efc0c15 | 2837 | } |
5260325f | 2838 | /* Start listening for connections on the socket. */ |
48e671d5 | 2839 | for (n = 0; n < num_socks; n++) { |
2840 | sock = socks[n]; | |
fce39749 | 2841 | if (listen(sock, SSH_LISTEN_BACKLOG) < 0) { |
48e671d5 | 2842 | error("listen: %.100s", strerror(errno)); |
48e671d5 | 2843 | close(sock); |
c9d0ad9b | 2844 | return -1; |
a7effaac | 2845 | } |
a7effaac | 2846 | } |
5260325f | 2847 | |
48e671d5 | 2848 | /* Allocate a channel for each socket. */ |
59e5aff5 | 2849 | *chanids = xmalloc(sizeof(**chanids) * (num_socks + 1)); |
48e671d5 | 2850 | for (n = 0; n < num_socks; n++) { |
2851 | sock = socks[n]; | |
ac151b18 | 2852 | nc = channel_new("x11 listener", |
0b242b12 | 2853 | SSH_CHANNEL_X11_LISTENER, sock, sock, -1, |
2854 | CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, | |
0d942eff | 2855 | 0, "X11 inet listener", 1); |
3a0d3d54 | 2856 | nc->single_connection = single_connection; |
59e5aff5 | 2857 | (*chanids)[n] = nc->self; |
48e671d5 | 2858 | } |
59e5aff5 | 2859 | (*chanids)[n] = -1; |
5260325f | 2860 | |
c9d0ad9b | 2861 | /* Return the display number for the DISPLAY environment variable. */ |
57f228e8 | 2862 | *display_numberp = display_number; |
2863 | return (0); | |
8efc0c15 | 2864 | } |
2865 | ||
396c147e | 2866 | static int |
1e3b8b07 | 2867 | connect_local_xsocket(u_int dnr) |
8efc0c15 | 2868 | { |
5260325f | 2869 | int sock; |
2870 | struct sockaddr_un addr; | |
5260325f | 2871 | |
805e659f | 2872 | sock = socket(AF_UNIX, SOCK_STREAM, 0); |
2873 | if (sock < 0) | |
2874 | error("socket: %.100s", strerror(errno)); | |
2875 | memset(&addr, 0, sizeof(addr)); | |
2876 | addr.sun_family = AF_UNIX; | |
2877 | snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr); | |
2878 | if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0) | |
2879 | return sock; | |
2880 | close(sock); | |
5260325f | 2881 | error("connect %.100s: %.100s", addr.sun_path, strerror(errno)); |
2882 | return -1; | |
8efc0c15 | 2883 | } |
2884 | ||
0b242b12 | 2885 | int |
2886 | x11_connect_display(void) | |
8efc0c15 | 2887 | { |
bcc0381e | 2888 | int display_number, sock = 0; |
5260325f | 2889 | const char *display; |
0b242b12 | 2890 | char buf[1024], *cp; |
48e671d5 | 2891 | struct addrinfo hints, *ai, *aitop; |
2892 | char strport[NI_MAXSERV]; | |
2893 | int gaierr; | |
5260325f | 2894 | |
5260325f | 2895 | /* Try to open a socket for the local X server. */ |
2896 | display = getenv("DISPLAY"); | |
2897 | if (!display) { | |
2898 | error("DISPLAY not set."); | |
0b242b12 | 2899 | return -1; |
5260325f | 2900 | } |
aa3378df | 2901 | /* |
2902 | * Now we decode the value of the DISPLAY variable and make a | |
2903 | * connection to the real X server. | |
2904 | */ | |
2905 | ||
2906 | /* | |
2907 | * Check if it is a unix domain socket. Unix domain displays are in | |
2908 | * one of the following formats: unix:d[.s], :d[.s], ::d[.s] | |
2909 | */ | |
5260325f | 2910 | if (strncmp(display, "unix:", 5) == 0 || |
2911 | display[0] == ':') { | |
2912 | /* Connect to the unix domain socket. */ | |
2913 | if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) { | |
2914 | error("Could not parse display number from DISPLAY: %.100s", | |
184eed6a | 2915 | display); |
0b242b12 | 2916 | return -1; |
5260325f | 2917 | } |
2918 | /* Create a socket. */ | |
2919 | sock = connect_local_xsocket(display_number); | |
2920 | if (sock < 0) | |
0b242b12 | 2921 | return -1; |
5260325f | 2922 | |
2923 | /* OK, we now have a connection to the display. */ | |
0b242b12 | 2924 | return sock; |
5260325f | 2925 | } |
aa3378df | 2926 | /* |
2927 | * Connect to an inet socket. The DISPLAY value is supposedly | |
2928 | * hostname:d[.s], where hostname may also be numeric IP address. | |
2929 | */ | |
74860245 | 2930 | strlcpy(buf, display, sizeof(buf)); |
5260325f | 2931 | cp = strchr(buf, ':'); |
2932 | if (!cp) { | |
2933 | error("Could not find ':' in DISPLAY: %.100s", display); | |
0b242b12 | 2934 | return -1; |
5260325f | 2935 | } |
2936 | *cp = 0; | |
aa3378df | 2937 | /* buf now contains the host name. But first we parse the display number. */ |
5260325f | 2938 | if (sscanf(cp + 1, "%d", &display_number) != 1) { |
2939 | error("Could not parse display number from DISPLAY: %.100s", | |
184eed6a | 2940 | display); |
0b242b12 | 2941 | return -1; |
5260325f | 2942 | } |
5260325f | 2943 | |
48e671d5 | 2944 | /* Look up the host address */ |
2945 | memset(&hints, 0, sizeof(hints)); | |
2946 | hints.ai_family = IPv4or6; | |
2947 | hints.ai_socktype = SOCK_STREAM; | |
2948 | snprintf(strport, sizeof strport, "%d", 6000 + display_number); | |
2949 | if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) { | |
2950 | error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr)); | |
0b242b12 | 2951 | return -1; |
8efc0c15 | 2952 | } |
48e671d5 | 2953 | for (ai = aitop; ai; ai = ai->ai_next) { |
2954 | /* Create a socket. */ | |
3e131a6d | 2955 | sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); |
48e671d5 | 2956 | if (sock < 0) { |
d7ac5f18 | 2957 | debug2("socket: %.100s", strerror(errno)); |
7368a6c8 | 2958 | continue; |
2959 | } | |
2960 | /* Connect it to the display. */ | |
2961 | if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
d7ac5f18 | 2962 | debug2("connect %.100s port %d: %.100s", buf, |
7368a6c8 | 2963 | 6000 + display_number, strerror(errno)); |
2964 | close(sock); | |
2965 | continue; | |
2966 | } | |
2967 | /* Success */ | |
2968 | break; | |
48e671d5 | 2969 | } |
48e671d5 | 2970 | freeaddrinfo(aitop); |
2971 | if (!ai) { | |
6ae2364d | 2972 | error("connect %.100s port %d: %.100s", buf, 6000 + display_number, |
48e671d5 | 2973 | strerror(errno)); |
0b242b12 | 2974 | return -1; |
8efc0c15 | 2975 | } |
bcc0381e | 2976 | set_nodelay(sock); |
0b242b12 | 2977 | return sock; |
2978 | } | |
5260325f | 2979 | |
0b242b12 | 2980 | /* |
2981 | * This is called when SSH_SMSG_X11_OPEN is received. The packet contains | |
2982 | * the remote channel number. We should do whatever we want, and respond | |
2983 | * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE. | |
2984 | */ | |
5260325f | 2985 | |
0b242b12 | 2986 | void |
7819b5c3 | 2987 | x11_input_open(int type, u_int32_t seq, void *ctxt) |
0b242b12 | 2988 | { |
719fc62f | 2989 | Channel *c = NULL; |
2990 | int remote_id, sock = 0; | |
0b242b12 | 2991 | char *remote_host; |
5260325f | 2992 | |
719fc62f | 2993 | debug("Received X11 open request."); |
5260325f | 2994 | |
719fc62f | 2995 | remote_id = packet_get_int(); |
8e7895b8 | 2996 | |
2997 | if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) { | |
719fc62f | 2998 | remote_host = packet_get_string(NULL); |
0b242b12 | 2999 | } else { |
3000 | remote_host = xstrdup("unknown (remote did not supply name)"); | |
0b242b12 | 3001 | } |
95500969 | 3002 | packet_check_eom(); |
0b242b12 | 3003 | |
3004 | /* Obtain a connection to the real X display. */ | |
3005 | sock = x11_connect_display(); | |
719fc62f | 3006 | if (sock != -1) { |
3007 | /* Allocate a channel for this connection. */ | |
3008 | c = channel_new("connected x11 socket", | |
3009 | SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0, | |
3010 | remote_host, 1); | |
3a0d3d54 | 3011 | c->remote_id = remote_id; |
3012 | c->force_drain = 1; | |
719fc62f | 3013 | } |
0d942eff | 3014 | xfree(remote_host); |
719fc62f | 3015 | if (c == NULL) { |
0b242b12 | 3016 | /* Send refusal to the remote host. */ |
3017 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
719fc62f | 3018 | packet_put_int(remote_id); |
0b242b12 | 3019 | } else { |
0b242b12 | 3020 | /* Send a confirmation to the remote host. */ |
3021 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
719fc62f | 3022 | packet_put_int(remote_id); |
3023 | packet_put_int(c->self); | |
0b242b12 | 3024 | } |
719fc62f | 3025 | packet_send(); |
8efc0c15 | 3026 | } |
3027 | ||
a22aff1f | 3028 | /* dummy protocol handler that denies SSH-1 requests (agent/x11) */ |
3029 | void | |
7819b5c3 | 3030 | deny_input_open(int type, u_int32_t seq, void *ctxt) |
a22aff1f | 3031 | { |
3032 | int rchan = packet_get_int(); | |
e1feb9bf | 3033 | |
6aacefa7 | 3034 | switch (type) { |
a22aff1f | 3035 | case SSH_SMSG_AGENT_OPEN: |
3036 | error("Warning: ssh server tried agent forwarding."); | |
3037 | break; | |
3038 | case SSH_SMSG_X11_OPEN: | |
3039 | error("Warning: ssh server tried X11 forwarding."); | |
3040 | break; | |
3041 | default: | |
7819b5c3 | 3042 | error("deny_input_open: type %d", type); |
a22aff1f | 3043 | break; |
3044 | } | |
1908529f | 3045 | error("Warning: this is probably a break-in attempt by a malicious server."); |
a22aff1f | 3046 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); |
3047 | packet_put_int(rchan); | |
3048 | packet_send(); | |
3049 | } | |
3050 | ||
aa3378df | 3051 | /* |
3052 | * Requests forwarding of X11 connections, generates fake authentication | |
3053 | * data, and enables authentication spoofing. | |
8e7895b8 | 3054 | * This should be called in the client only. |
aa3378df | 3055 | */ |
6ae2364d | 3056 | void |
9bf083eb | 3057 | x11_request_forwarding_with_spoofing(int client_session_id, const char *disp, |
0b242b12 | 3058 | const char *proto, const char *data) |
8efc0c15 | 3059 | { |
1e3b8b07 | 3060 | u_int data_len = (u_int) strlen(data) / 2; |
ef07103c | 3061 | u_int i, value; |
5260325f | 3062 | char *new_data; |
3063 | int screen_number; | |
3064 | const char *cp; | |
ca75d7de | 3065 | u_int32_t rnd = 0; |
5260325f | 3066 | |
4297b666 | 3067 | if (x11_saved_display == NULL) |
3068 | x11_saved_display = xstrdup(disp); | |
3069 | else if (strcmp(disp, x11_saved_display) != 0) { | |
ef07103c | 3070 | error("x11_request_forwarding_with_spoofing: different " |
3071 | "$DISPLAY already forwarded"); | |
3072 | return; | |
3073 | } | |
3074 | ||
9bf083eb | 3075 | cp = disp; |
3076 | if (disp) | |
3077 | cp = strchr(disp, ':'); | |
5260325f | 3078 | if (cp) |
3079 | cp = strchr(cp, '.'); | |
3080 | if (cp) | |
3081 | screen_number = atoi(cp + 1); | |
3082 | else | |
3083 | screen_number = 0; | |
3084 | ||
ef07103c | 3085 | if (x11_saved_proto == NULL) { |
3086 | /* Save protocol name. */ | |
3087 | x11_saved_proto = xstrdup(proto); | |
3088 | /* | |
56964485 | 3089 | * Extract real authentication data and generate fake data |
ef07103c | 3090 | * of the same length. |
3091 | */ | |
3092 | x11_saved_data = xmalloc(data_len); | |
3093 | x11_fake_data = xmalloc(data_len); | |
3094 | for (i = 0; i < data_len; i++) { | |
3095 | if (sscanf(data + 2 * i, "%2x", &value) != 1) | |
3096 | fatal("x11_request_forwarding: bad " | |
3097 | "authentication data: %.100s", data); | |
3098 | if (i % 4 == 0) | |
3099 | rnd = arc4random(); | |
3100 | x11_saved_data[i] = value; | |
3101 | x11_fake_data[i] = rnd & 0xff; | |
3102 | rnd >>= 8; | |
3103 | } | |
3104 | x11_saved_data_len = data_len; | |
3105 | x11_fake_data_len = data_len; | |
3106 | } | |
5260325f | 3107 | |
3108 | /* Convert the fake data into hex. */ | |
ef07103c | 3109 | new_data = tohex(x11_fake_data, data_len); |
5260325f | 3110 | |
3111 | /* Send the request packet. */ | |
0b242b12 | 3112 | if (compat20) { |
3113 | channel_request_start(client_session_id, "x11-req", 0); | |
3114 | packet_put_char(0); /* XXX bool single connection */ | |
3115 | } else { | |
3116 | packet_start(SSH_CMSG_X11_REQUEST_FORWARDING); | |
3117 | } | |
3118 | packet_put_cstring(proto); | |
3119 | packet_put_cstring(new_data); | |
5260325f | 3120 | packet_put_int(screen_number); |
3121 | packet_send(); | |
3122 | packet_write_wait(); | |
3123 | xfree(new_data); | |
8efc0c15 | 3124 | } |
3125 | ||
8e7895b8 | 3126 | |
3127 | /* -- agent forwarding */ | |
3128 | ||
8efc0c15 | 3129 | /* Sends a message to the server to request authentication fd forwarding. */ |
3130 | ||
6ae2364d | 3131 | void |
d5bb9418 | 3132 | auth_request_forwarding(void) |
8efc0c15 | 3133 | { |
5260325f | 3134 | packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING); |
3135 | packet_send(); | |
3136 | packet_write_wait(); | |
8efc0c15 | 3137 | } |