]> andersk Git - openssh.git/blame - channels.c
andersk / openssh.git / blame
? search:
summary | shortlog | log | commit | commitdiff | tree
blob | blame (incremental) | history | HEAD
- reyk@cvs.openbsd.org 2009/10/28 16:38:18
[openssh.git] / channels.c
CommitLineData
fe7dba42 1/* $OpenBSD: channels.c,v 1.297 2009/10/28 16:38:18 reyk Exp $ */
8efc0c15 2/*
5260325f 3 * Author: Tatu Ylonen <ylo@cs.hut.fi>
5260325f 4 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5 * All rights reserved
5260325f 6 * This file contains functions for generic socket connection forwarding.
7 * There is also code for initiating connection forwarding for X11 connections,
8 * arbitrary tcp/ip connections, and the authentication agent connection.
6ae2364d 9 *
bcbf86ec 10 * As far as I am concerned, the code I have written for this software
11 * can be used freely for any purpose. Any derived versions of this
12 * software must be clearly marked as such, and if the derived work is
13 * incompatible with the protocol description in the RFC file, it must be
14 * called by a name other than "ssh" or "Secure Shell".
15 *
7e7327a1 16 * SSH2 support added by Markus Friedl.
8341f420 17 * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
bcbf86ec 18 * Copyright (c) 1999 Dug Song. All rights reserved.
19 * Copyright (c) 1999 Theo de Raadt. All rights reserved.
20 *
21 * Redistribution and use in source and binary forms, with or without
22 * modification, are permitted provided that the following conditions
23 * are met:
24 * 1. Redistributions of source code must retain the above copyright
25 * notice, this list of conditions and the following disclaimer.
26 * 2. Redistributions in binary form must reproduce the above copyright
27 * notice, this list of conditions and the following disclaimer in the
28 * documentation and/or other materials provided with the distribution.
29 *
30 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
31 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
33 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
34 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
35 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
39 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
5260325f 40 */
8efc0c15 41
42#include "includes.h"
bd7c69ea 43
cebb4c24 44#include <sys/types.h>
31652869 45#include <sys/ioctl.h>
cebb4c24 46#include <sys/un.h>
319d6b41 47#include <sys/socket.h>
e264ac72 48#ifdef HAVE_SYS_TIME_H
49# include <sys/time.h>
50#endif
319d6b41 51
52#include <netinet/in.h>
53#include <arpa/inet.h>
1d3e026f 54
028094f4 55#include <errno.h>
28cb0a43 56#include <netdb.h>
cf851879 57#include <stdio.h>
ffa517a8 58#include <stdlib.h>
00146caa 59#include <string.h>
1d3e026f 60#include <termios.h>
5188ba17 61#include <unistd.h>
31652869 62#include <stdarg.h>
8efc0c15 63
3593bdc0 64#include "openbsd-compat/sys-queue.h"
31652869 65#include "xmalloc.h"
8efc0c15 66#include "ssh.h"
42f11eb2 67#include "ssh1.h"
68#include "ssh2.h"
8efc0c15 69#include "packet.h"
42f11eb2 70#include "log.h"
71#include "misc.h"
31652869 72#include "buffer.h"
8efc0c15 73#include "channels.h"
8efc0c15 74#include "compat.h"
42f11eb2 75#include "canohost.h"
4c8722d9 76#include "key.h"
77#include "authfd.h"
805e659f 78#include "pathnames.h"
8efc0c15 79
8e7895b8 80/* -- channel core */
8efc0c15 81
aa3378df 82/*
83 * Pointer to an array containing all allocated channels. The array is
84 * dynamically extended as needed.
85 */
719fc62f 86static Channel **channels = NULL;
8efc0c15 87
aa3378df 88/*
89 * Size of the channel array. All slots of the array must always be
719fc62f 90 * initialized (at least the type field); unused slots set to NULL
aa3378df 91 */
9a995072 92static u_int channels_alloc = 0;
8efc0c15 93
aa3378df 94/*
95 * Maximum file descriptor value used in any of the channels. This is
719fc62f 96 * updated in channel_new.
aa3378df 97 */
39929cdb 98static int channel_max_fd = 0;
8efc0c15 99
8efc0c15 100
8e7895b8 101/* -- tcp forwarding */
8efc0c15 102
aa3378df 103/*
104 * Data structure for storing which hosts are permitted for forward requests.
105 * The local sides of any remote forwards are stored in this array to prevent
106 * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
107 * network (which might be behind a firewall).
108 */
5260325f 109typedef struct {
7368a6c8 110 char *host_to_connect; /* Connect to 'host'. */
111 u_short port_to_connect; /* Connect to 'port'. */
112 u_short listen_port; /* Remote side should listen port number. */
8efc0c15 113} ForwardPermission;
114
2fefbadf 115/* List of all permitted host/port pairs to connect by the user. */
8efc0c15 116static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
8e7895b8 117
2fefbadf 118/* List of all permitted host/port pairs to connect by the admin. */
119static ForwardPermission permitted_adm_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
120
121/* Number of permitted host/port pairs in the array permitted by the user. */
8efc0c15 122static int num_permitted_opens = 0;
2fefbadf 123
124/* Number of permitted host/port pair in the array permitted by the admin. */
125static int num_adm_permitted_opens = 0;
126
aa3378df 127/*
128 * If this is true, all opens are permitted. This is the case on the server
129 * on which we have to trust the client anyway, and the user could do
130 * anything after logging in anyway.
131 */
8efc0c15 132static int all_opens_permitted = 0;
133
8efc0c15 134
8e7895b8 135/* -- X11 forwarding */
42f11eb2 136
8e7895b8 137/* Maximum number of fake X11 displays to try. */
138#define MAX_DISPLAYS 1000
0490e609 139
ef07103c 140/* Saved X11 local (client) display. */
141static char *x11_saved_display = NULL;
142
8e7895b8 143/* Saved X11 authentication protocol name. */
144static char *x11_saved_proto = NULL;
8efc0c15 145
8e7895b8 146/* Saved X11 authentication data. This is the real data. */
147static char *x11_saved_data = NULL;
148static u_int x11_saved_data_len = 0;
149
150/*
151 * Fake X11 authentication data. This is what the server will be sending us;
152 * we should replace any occurrences of this by the real data.
153 */
338eb2ab 154static u_char *x11_fake_data = NULL;
8e7895b8 155static u_int x11_fake_data_len;
156
157
158/* -- agent forwarding */
8efc0c15 159
8e7895b8 160#define NUM_SOCKS 10
161
8e7895b8 162/* AF_UNSPEC or AF_INET or AF_INET6 */
5e4a7219 163static int IPv4or6 = AF_UNSPEC;
8e7895b8 164
fe7dba42 165/* Set the routing domain a.k.a. VRF */
166static int channel_rdomain = -1;
167
8e7895b8 168/* helper */
396c147e 169static void port_open_helper(Channel *c, char *rtype);
8e7895b8 170
e07e21ad 171/* non-blocking connect helpers */
172static int connect_next(struct channel_connect *);
173static void channel_connect_ctx_free(struct channel_connect *);
174
8e7895b8 175/* -- channel core */
7368a6c8 176
177Channel *
b872f7f0 178channel_by_id(int id)
7368a6c8 179{
180 Channel *c;
719fc62f 181
9a995072 182 if (id < 0 || (u_int)id >= channels_alloc) {
b872f7f0 183 logit("channel_by_id: %d: bad id", id);
7368a6c8 184 return NULL;
185 }
719fc62f 186 c = channels[id];
187 if (c == NULL) {
b872f7f0 188 logit("channel_by_id: %d: bad id: channel free", id);
7368a6c8 189 return NULL;
190 }
191 return c;
192}
193
b872f7f0 194/*
195 * Returns the channel if it is allowed to receive protocol messages.
196 * Private channels, like listening sockets, may not receive messages.
197 */
198Channel *
199channel_lookup(int id)
200{
201 Channel *c;
202
203 if ((c = channel_by_id(id)) == NULL)
204 return (NULL);
205
c8e9c167 206 switch (c->type) {
b872f7f0 207 case SSH_CHANNEL_X11_OPEN:
208 case SSH_CHANNEL_LARVAL:
209 case SSH_CHANNEL_CONNECTING:
210 case SSH_CHANNEL_DYNAMIC:
211 case SSH_CHANNEL_OPENING:
212 case SSH_CHANNEL_OPEN:
213 case SSH_CHANNEL_INPUT_DRAINING:
214 case SSH_CHANNEL_OUTPUT_DRAINING:
215 return (c);
b872f7f0 216 }
217 logit("Non-public channel %d, type %d.", id, c->type);
218 return (NULL);
219}
220
aa3378df 221/*
1d1ffb87 222 * Register filedescriptors for a channel, used when allocating a channel or
0fbe8c74 223 * when the channel consumer/producer is ready, e.g. shell exec'd
aa3378df 224 */
396c147e 225static void
a22aff1f 226channel_register_fds(Channel *c, int rfd, int wfd, int efd,
b3784859 227 int extusage, int nonblock, int is_tty)
8efc0c15 228{
5260325f 229 /* Update the maximum file descriptor value. */
39929cdb 230 channel_max_fd = MAX(channel_max_fd, rfd);
231 channel_max_fd = MAX(channel_max_fd, wfd);
232 channel_max_fd = MAX(channel_max_fd, efd);
233
aa3378df 234 /* XXX set close-on-exec -markus */
1d1ffb87 235
0fbe8c74 236 c->rfd = rfd;
237 c->wfd = wfd;
238 c->sock = (rfd == wfd) ? rfd : -1;
5e96b616 239 c->ctl_fd = -1; /* XXX: set elsewhere */
0fbe8c74 240 c->efd = efd;
241 c->extended_usage = extusage;
a22aff1f 242
b3784859 243 if ((c->isatty = is_tty) != 0)
d7ac5f18 244 debug2("channel %d: rfd %d isatty", c->self, c->rfd);
245f4d36 245 c->wfd_isatty = is_tty || isatty(c->wfd);
0ae4fe1d 246
a22aff1f 247 /* enable nonblocking mode */
248 if (nonblock) {
249 if (rfd != -1)
250 set_nonblock(rfd);
251 if (wfd != -1)
252 set_nonblock(wfd);
253 if (efd != -1)
254 set_nonblock(efd);
255 }
0fbe8c74 256}
257
258/*
259 * Allocate a new channel object and set its type and socket. This will cause
260 * remote_name to be freed.
261 */
719fc62f 262Channel *
0fbe8c74 263channel_new(char *ctype, int type, int rfd, int wfd, int efd,
f91d9a89 264 u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
0fbe8c74 265{
9a995072 266 int found;
267 u_int i;
0fbe8c74 268 Channel *c;
5260325f 269
270 /* Do initial allocation if this is the first call. */
271 if (channels_alloc == 0) {
272 channels_alloc = 10;
52e3daed 273 channels = xcalloc(channels_alloc, sizeof(Channel *));
5260325f 274 for (i = 0; i < channels_alloc; i++)
719fc62f 275 channels[i] = NULL;
5260325f 276 }
277 /* Try to find a free slot where to put the new channel. */
278 for (found = -1, i = 0; i < channels_alloc; i++)
719fc62f 279 if (channels[i] == NULL) {
5260325f 280 /* Found a free slot. */
9a995072 281 found = (int)i;
5260325f 282 break;
283 }
9a995072 284 if (found < 0) {
aa3378df 285 /* There are no free slots. Take last+1 slot and expand the array. */
5260325f 286 found = channels_alloc;
5df8c731 287 if (channels_alloc > 10000)
288 fatal("channel_new: internal error: channels_alloc %d "
289 "too big.", channels_alloc);
c5d10563 290 channels = xrealloc(channels, channels_alloc + 10,
291 sizeof(Channel *));
20419cc1 292 channels_alloc += 10;
de273eef 293 debug2("channel: expanding %d", channels_alloc);
5260325f 294 for (i = found; i < channels_alloc; i++)
719fc62f 295 channels[i] = NULL;
5260325f 296 }
719fc62f 297 /* Initialize and return new channel. */
52e3daed 298 c = channels[found] = xcalloc(1, sizeof(Channel));
5260325f 299 buffer_init(&c->input);
300 buffer_init(&c->output);
7368a6c8 301 buffer_init(&c->extended);
1338ba77 302 c->path = NULL;
70bef40e 303 c->ostate = CHAN_OUTPUT_OPEN;
304 c->istate = CHAN_INPUT_OPEN;
305 c->flags = 0;
c9478090 306 channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, 0);
5260325f 307 c->self = found;
308 c->type = type;
7368a6c8 309 c->ctype = ctype;
0b242b12 310 c->local_window = window;
311 c->local_window_max = window;
312 c->local_consumed = 0;
313 c->local_maxpacket = maxpack;
5260325f 314 c->remote_id = -1;
0d942eff 315 c->remote_name = xstrdup(remote_name);
7368a6c8 316 c->remote_window = 0;
317 c->remote_maxpacket = 0;
a5f82435 318 c->force_drain = 0;
ac151b18 319 c->single_connection = 0;
3cf2be58 320 c->detach_user = NULL;
8cd0437d 321 c->detach_close = 0;
3593bdc0 322 c->open_confirm = NULL;
323 c->open_confirm_ctx = NULL;
2e73a022 324 c->input_filter = NULL;
c1c6a032 325 c->output_filter = NULL;
e74caf1e 326 c->filter_ctx = NULL;
327 c->filter_cleanup = NULL;
3593bdc0 328 TAILQ_INIT(&c->status_confirms);
5260325f 329 debug("channel %d: new [%s]", found, remote_name);
719fc62f 330 return c;
7368a6c8 331}
8efc0c15 332
489aa2e9 333static int
334channel_find_maxfd(void)
335{
9a995072 336 u_int i;
337 int max = 0;
489aa2e9 338 Channel *c;
339
340 for (i = 0; i < channels_alloc; i++) {
341 c = channels[i];
342 if (c != NULL) {
343 max = MAX(max, c->rfd);
344 max = MAX(max, c->wfd);
345 max = MAX(max, c->efd);
346 }
347 }
348 return max;
349}
350
351int
352channel_close_fd(int *fdp)
353{
354 int ret = 0, fd = *fdp;
355
356 if (fd != -1) {
357 ret = close(fd);
358 *fdp = -1;
359 if (fd == channel_max_fd)
360 channel_max_fd = channel_find_maxfd();
361 }
362 return ret;
363}
364
0fbe8c74 365/* Close all channel fd/socket. */
396c147e 366static void
0fbe8c74 367channel_close_fds(Channel *c)
368{
5e96b616 369 debug3("channel %d: close_fds r %d w %d e %d c %d",
370 c->self, c->rfd, c->wfd, c->efd, c->ctl_fd);
6fd8622b 371
489aa2e9 372 channel_close_fd(&c->sock);
5e96b616 373 channel_close_fd(&c->ctl_fd);
489aa2e9 374 channel_close_fd(&c->rfd);
375 channel_close_fd(&c->wfd);
376 channel_close_fd(&c->efd);
0fbe8c74 377}
378
8e7895b8 379/* Free the channel and close its fd/socket. */
8e7895b8 380void
381channel_free(Channel *c)
382{
383 char *s;
9a995072 384 u_int i, n;
3593bdc0 385 struct channel_confirm *cc;
8e7895b8 386
387 for (n = 0, i = 0; i < channels_alloc; i++)
388 if (channels[i])
389 n++;
9a995072 390 debug("channel %d: free: %s, nchannels %u", c->self,
8e7895b8 391 c->remote_name ? c->remote_name : "???", n);
392
393 s = channel_open_message();
d7ac5f18 394 debug3("channel %d: status: %s", c->self, s);
8e7895b8 395 xfree(s);
396
8e7895b8 397 if (c->sock != -1)
398 shutdown(c->sock, SHUT_RDWR);
5e96b616 399 if (c->ctl_fd != -1)
400 shutdown(c->ctl_fd, SHUT_RDWR);
8e7895b8 401 channel_close_fds(c);
402 buffer_free(&c->input);
403 buffer_free(&c->output);
404 buffer_free(&c->extended);
405 if (c->remote_name) {
406 xfree(c->remote_name);
407 c->remote_name = NULL;
408 }
1338ba77 409 if (c->path) {
410 xfree(c->path);
411 c->path = NULL;
412 }
3593bdc0 413 while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
414 if (cc->abandon_cb != NULL)
415 cc->abandon_cb(c, cc->ctx);
416 TAILQ_REMOVE(&c->status_confirms, cc, entry);
417 bzero(cc, sizeof(*cc));
418 xfree(cc);
419 }
e74caf1e 420 if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
421 c->filter_cleanup(c->self, c->filter_ctx);
8e7895b8 422 channels[c->self] = NULL;
423 xfree(c);
424}
425
8e7895b8 426void
d6746a0b 427channel_free_all(void)
8e7895b8 428{
9a995072 429 u_int i;
8e7895b8 430
d6746a0b 431 for (i = 0; i < channels_alloc; i++)
432 if (channels[i] != NULL)
433 channel_free(channels[i]);
8e7895b8 434}
435
436/*
437 * Closes the sockets/fds of all channels. This is used to close extra file
438 * descriptors after a fork.
439 */
8e7895b8 440void
d5bb9418 441channel_close_all(void)
8e7895b8 442{
9a995072 443 u_int i;
8e7895b8 444
445 for (i = 0; i < channels_alloc; i++)
446 if (channels[i] != NULL)
447 channel_close_fds(channels[i]);
448}
449
3cf2be58 450/*
451 * Stop listening to channels.
452 */
3cf2be58 453void
454channel_stop_listening(void)
455{
9a995072 456 u_int i;
3cf2be58 457 Channel *c;
458
459 for (i = 0; i < channels_alloc; i++) {
460 c = channels[i];
461 if (c != NULL) {
462 switch (c->type) {
463 case SSH_CHANNEL_AUTH_SOCKET:
464 case SSH_CHANNEL_PORT_LISTENER:
465 case SSH_CHANNEL_RPORT_LISTENER:
466 case SSH_CHANNEL_X11_LISTENER:
489aa2e9 467 channel_close_fd(&c->sock);
3cf2be58 468 channel_free(c);
469 break;
470 }
471 }
472 }
473}
474
8e7895b8 475/*
476 * Returns true if no channel has too much buffered data, and false if one or
477 * more channel is overfull.
478 */
8e7895b8 479int
d5bb9418 480channel_not_very_much_buffered_data(void)
8e7895b8 481{
482 u_int i;
483 Channel *c;
484
485 for (i = 0; i < channels_alloc; i++) {
486 c = channels[i];
487 if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
0c139bd1 488#if 0
489 if (!compat20 &&
490 buffer_len(&c->input) > packet_get_maxsize()) {
faa483fa 491 debug2("channel %d: big input buffer %d",
8e7895b8 492 c->self, buffer_len(&c->input));
493 return 0;
494 }
0c139bd1 495#endif
8e7895b8 496 if (buffer_len(&c->output) > packet_get_maxsize()) {
a27002e5 497 debug2("channel %d: big output buffer %u > %u",
0c139bd1 498 c->self, buffer_len(&c->output),
499 packet_get_maxsize());
8e7895b8 500 return 0;
501 }
502 }
503 }
504 return 1;
505}
506
507/* Returns true if any channel is still open. */
8e7895b8 508int
d5bb9418 509channel_still_open(void)
8e7895b8 510{
9a995072 511 u_int i;
8e7895b8 512 Channel *c;
513
514 for (i = 0; i < channels_alloc; i++) {
515 c = channels[i];
516 if (c == NULL)
517 continue;
518 switch (c->type) {
519 case SSH_CHANNEL_X11_LISTENER:
520 case SSH_CHANNEL_PORT_LISTENER:
521 case SSH_CHANNEL_RPORT_LISTENER:
522 case SSH_CHANNEL_CLOSED:
523 case SSH_CHANNEL_AUTH_SOCKET:
524 case SSH_CHANNEL_DYNAMIC:
525 case SSH_CHANNEL_CONNECTING:
526 case SSH_CHANNEL_ZOMBIE:
527 continue;
528 case SSH_CHANNEL_LARVAL:
529 if (!compat20)
530 fatal("cannot happen: SSH_CHANNEL_LARVAL");
531 continue;
532 case SSH_CHANNEL_OPENING:
533 case SSH_CHANNEL_OPEN:
534 case SSH_CHANNEL_X11_OPEN:
535 return 1;
536 case SSH_CHANNEL_INPUT_DRAINING:
537 case SSH_CHANNEL_OUTPUT_DRAINING:
538 if (!compat13)
539 fatal("cannot happen: OUT_DRAIN");
540 return 1;
541 default:
542 fatal("channel_still_open: bad channel type %d", c->type);
543 /* NOTREACHED */
544 }
545 }
546 return 0;
547}
548
549/* Returns the id of an open channel suitable for keepaliving */
8e7895b8 550int
d5bb9418 551channel_find_open(void)
8e7895b8 552{
9a995072 553 u_int i;
8e7895b8 554 Channel *c;
555
556 for (i = 0; i < channels_alloc; i++) {
557 c = channels[i];
13de3560 558 if (c == NULL || c->remote_id < 0)
8e7895b8 559 continue;
560 switch (c->type) {
561 case SSH_CHANNEL_CLOSED:
562 case SSH_CHANNEL_DYNAMIC:
563 case SSH_CHANNEL_X11_LISTENER:
564 case SSH_CHANNEL_PORT_LISTENER:
565 case SSH_CHANNEL_RPORT_LISTENER:
566 case SSH_CHANNEL_OPENING:
567 case SSH_CHANNEL_CONNECTING:
568 case SSH_CHANNEL_ZOMBIE:
569 continue;
570 case SSH_CHANNEL_LARVAL:
571 case SSH_CHANNEL_AUTH_SOCKET:
572 case SSH_CHANNEL_OPEN:
573 case SSH_CHANNEL_X11_OPEN:
574 return i;
575 case SSH_CHANNEL_INPUT_DRAINING:
576 case SSH_CHANNEL_OUTPUT_DRAINING:
577 if (!compat13)
578 fatal("cannot happen: OUT_DRAIN");
579 return i;
580 default:
581 fatal("channel_find_open: bad channel type %d", c->type);
582 /* NOTREACHED */
583 }
584 }
585 return -1;
586}
587
588
589/*
590 * Returns a message describing the currently open forwarded connections,
591 * suitable for sending to the client. The message contains crlf pairs for
592 * newlines.
593 */
8e7895b8 594char *
d5bb9418 595channel_open_message(void)
8e7895b8 596{
597 Buffer buffer;
598 Channel *c;
599 char buf[1024], *cp;
9a995072 600 u_int i;
8e7895b8 601
602 buffer_init(&buffer);
603 snprintf(buf, sizeof buf, "The following connections are open:\r\n");
604 buffer_append(&buffer, buf, strlen(buf));
605 for (i = 0; i < channels_alloc; i++) {
606 c = channels[i];
607 if (c == NULL)
608 continue;
609 switch (c->type) {
610 case SSH_CHANNEL_X11_LISTENER:
611 case SSH_CHANNEL_PORT_LISTENER:
612 case SSH_CHANNEL_RPORT_LISTENER:
613 case SSH_CHANNEL_CLOSED:
614 case SSH_CHANNEL_AUTH_SOCKET:
615 case SSH_CHANNEL_ZOMBIE:
616 continue;
617 case SSH_CHANNEL_LARVAL:
618 case SSH_CHANNEL_OPENING:
619 case SSH_CHANNEL_CONNECTING:
620 case SSH_CHANNEL_DYNAMIC:
621 case SSH_CHANNEL_OPEN:
622 case SSH_CHANNEL_X11_OPEN:
623 case SSH_CHANNEL_INPUT_DRAINING:
624 case SSH_CHANNEL_OUTPUT_DRAINING:
5e96b616 625 snprintf(buf, sizeof buf,
626 " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d cfd %d)\r\n",
8e7895b8 627 c->self, c->remote_name,
628 c->type, c->remote_id,
629 c->istate, buffer_len(&c->input),
630 c->ostate, buffer_len(&c->output),
5e96b616 631 c->rfd, c->wfd, c->ctl_fd);
8e7895b8 632 buffer_append(&buffer, buf, strlen(buf));
633 continue;
634 default:
635 fatal("channel_open_message: bad channel type %d", c->type);
636 /* NOTREACHED */
637 }
638 }
639 buffer_append(&buffer, "\0", 1);
640 cp = xstrdup(buffer_ptr(&buffer));
641 buffer_free(&buffer);
642 return cp;
643}
644
645void
646channel_send_open(int id)
647{
648 Channel *c = channel_lookup(id);
e1feb9bf 649
8e7895b8 650 if (c == NULL) {
bbe88b6d 651 logit("channel_send_open: %d: bad id", id);
8e7895b8 652 return;
653 }
6226a8f8 654 debug2("channel %d: send open", id);
8e7895b8 655 packet_start(SSH2_MSG_CHANNEL_OPEN);
656 packet_put_cstring(c->ctype);
657 packet_put_int(c->self);
658 packet_put_int(c->local_window);
659 packet_put_int(c->local_maxpacket);
660 packet_send();
661}
662
663void
6226a8f8 664channel_request_start(int id, char *service, int wantconfirm)
8e7895b8 665{
6226a8f8 666 Channel *c = channel_lookup(id);
e1feb9bf 667
8e7895b8 668 if (c == NULL) {
bbe88b6d 669 logit("channel_request_start: %d: unknown channel id", id);
8e7895b8 670 return;
671 }
5e96b616 672 debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
8e7895b8 673 packet_start(SSH2_MSG_CHANNEL_REQUEST);
674 packet_put_int(c->remote_id);
675 packet_put_cstring(service);
676 packet_put_char(wantconfirm);
677}
a7137f6b 678
8e7895b8 679void
3593bdc0 680channel_register_status_confirm(int id, channel_confirm_cb *cb,
681 channel_confirm_abandon_cb *abandon_cb, void *ctx)
682{
683 struct channel_confirm *cc;
684 Channel *c;
685
686 if ((c = channel_lookup(id)) == NULL)
687 fatal("channel_register_expect: %d: bad id", id);
688
689 cc = xmalloc(sizeof(*cc));
690 cc->cb = cb;
691 cc->abandon_cb = abandon_cb;
692 cc->ctx = ctx;
693 TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
694}
695
696void
697channel_register_open_confirm(int id, channel_callback_fn *fn, void *ctx)
8e7895b8 698{
699 Channel *c = channel_lookup(id);
e1feb9bf 700
8e7895b8 701 if (c == NULL) {
2ea438c2 702 logit("channel_register_open_confirm: %d: bad id", id);
8e7895b8 703 return;
704 }
3593bdc0 705 c->open_confirm = fn;
706 c->open_confirm_ctx = ctx;
8e7895b8 707}
a7137f6b 708
8e7895b8 709void
8cd0437d 710channel_register_cleanup(int id, channel_callback_fn *fn, int do_close)
8e7895b8 711{
b872f7f0 712 Channel *c = channel_by_id(id);
e1feb9bf 713
8e7895b8 714 if (c == NULL) {
bbe88b6d 715 logit("channel_register_cleanup: %d: bad id", id);
8e7895b8 716 return;
717 }
3cf2be58 718 c->detach_user = fn;
8cd0437d 719 c->detach_close = do_close;
8e7895b8 720}
a7137f6b 721
8e7895b8 722void
723channel_cancel_cleanup(int id)
724{
b872f7f0 725 Channel *c = channel_by_id(id);
e1feb9bf 726
8e7895b8 727 if (c == NULL) {
bbe88b6d 728 logit("channel_cancel_cleanup: %d: bad id", id);
8e7895b8 729 return;
730 }
3cf2be58 731 c->detach_user = NULL;
8cd0437d 732 c->detach_close = 0;
8e7895b8 733}
a7137f6b 734
8e7895b8 735void
c1c6a032 736channel_register_filter(int id, channel_infilter_fn *ifn,
e74caf1e 737 channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
8e7895b8 738{
739 Channel *c = channel_lookup(id);
e1feb9bf 740
8e7895b8 741 if (c == NULL) {
bbe88b6d 742 logit("channel_register_filter: %d: bad id", id);
8e7895b8 743 return;
744 }
c1c6a032 745 c->input_filter = ifn;
746 c->output_filter = ofn;
f17f705b 747 c->filter_ctx = ctx;
e74caf1e 748 c->filter_cleanup = cfn;
8e7895b8 749}
750
6ae2364d 751void
8e7895b8 752channel_set_fds(int id, int rfd, int wfd, int efd,
b3784859 753 int extusage, int nonblock, int is_tty, u_int window_max)
8efc0c15 754{
8e7895b8 755 Channel *c = channel_lookup(id);
e1feb9bf 756
8e7895b8 757 if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
758 fatal("channel_activate for non-larval channel %d.", id);
b3784859 759 channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, is_tty);
8e7895b8 760 c->type = SSH_CHANNEL_OPEN;
399d1ea6 761 c->local_window = c->local_window_max = window_max;
8e7895b8 762 packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
763 packet_put_int(c->remote_id);
764 packet_put_int(c->local_window);
765 packet_send();
8efc0c15 766}
767
aa3378df 768/*
7368a6c8 769 * 'channel_pre*' are called just before select() to add any bits relevant to
770 * channels in the select bitmasks.
aa3378df 771 */
7368a6c8 772/*
773 * 'channel_post*': perform any appropriate operations for channels which
774 * have events pending.
775 */
c8e9c167 776typedef void chan_fn(Channel *c, fd_set *readset, fd_set *writeset);
7368a6c8 777chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
778chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
8efc0c15 779
ebb90778 780/* ARGSUSED */
396c147e 781static void
c8e9c167 782channel_pre_listener(Channel *c, fd_set *readset, fd_set *writeset)
8efc0c15 783{
7368a6c8 784 FD_SET(c->sock, readset);
785}
5260325f 786
ebb90778 787/* ARGSUSED */
396c147e 788static void
c8e9c167 789channel_pre_connecting(Channel *c, fd_set *readset, fd_set *writeset)
97fb6912 790{
791 debug3("channel %d: waiting for connection", c->self);
792 FD_SET(c->sock, writeset);
793}
794
396c147e 795static void
c8e9c167 796channel_pre_open_13(Channel *c, fd_set *readset, fd_set *writeset)
7368a6c8 797{
798 if (buffer_len(&c->input) < packet_get_maxsize())
799 FD_SET(c->sock, readset);
800 if (buffer_len(&c->output) > 0)
801 FD_SET(c->sock, writeset);
802}
5260325f 803
396c147e 804static void
c8e9c167 805channel_pre_open(Channel *c, fd_set *readset, fd_set *writeset)
7368a6c8 806{
0c0738d5 807 u_int limit = compat20 ? c->remote_window : packet_get_maxsize();
5260325f 808
7e7327a1 809 if (c->istate == CHAN_INPUT_OPEN &&
0c0738d5 810 limit > 0 &&
69d9d413 811 buffer_len(&c->input) < limit &&
812 buffer_check_alloc(&c->input, CHAN_RBUF))
7e7327a1 813 FD_SET(c->rfd, readset);
814 if (c->ostate == CHAN_OUTPUT_OPEN ||
815 c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
816 if (buffer_len(&c->output) > 0) {
817 FD_SET(c->wfd, writeset);
818 } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
d2296ed7 819 if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
4e2e5cfd 820 debug2("channel %d: obuf_empty delayed efd %d/(%d)",
821 c->self, c->efd, buffer_len(&c->extended));
d2296ed7 822 else
823 chan_obuf_empty(c);
7e7327a1 824 }
825 }
826 /** XXX check close conditions, too */
271f4a13 827 if (compat20 && c->efd != -1 &&
828 !(c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED)) {
7e7327a1 829 if (c->extended_usage == CHAN_EXTENDED_WRITE &&
830 buffer_len(&c->extended) > 0)
831 FD_SET(c->efd, writeset);
d2296ed7 832 else if (!(c->flags & CHAN_EOF_SENT) &&
833 c->extended_usage == CHAN_EXTENDED_READ &&
7e7327a1 834 buffer_len(&c->extended) < c->remote_window)
835 FD_SET(c->efd, readset);
836 }
5e96b616 837 /* XXX: What about efd? races? */
f2107e97 838 if (compat20 && c->ctl_fd != -1 &&
5e96b616 839 c->istate == CHAN_INPUT_OPEN && c->ostate == CHAN_OUTPUT_OPEN)
840 FD_SET(c->ctl_fd, readset);
7e7327a1 841}
842
ebb90778 843/* ARGSUSED */
396c147e 844static void
c8e9c167 845channel_pre_input_draining(Channel *c, fd_set *readset, fd_set *writeset)
7368a6c8 846{
847 if (buffer_len(&c->input) == 0) {
848 packet_start(SSH_MSG_CHANNEL_CLOSE);
849 packet_put_int(c->remote_id);
850 packet_send();
851 c->type = SSH_CHANNEL_CLOSED;
d7ac5f18 852 debug2("channel %d: closing after input drain.", c->self);
7368a6c8 853 }
854}
5260325f 855
ebb90778 856/* ARGSUSED */
396c147e 857static void
c8e9c167 858channel_pre_output_draining(Channel *c, fd_set *readset, fd_set *writeset)
7368a6c8 859{
860 if (buffer_len(&c->output) == 0)
719fc62f 861 chan_mark_dead(c);
6ae2364d 862 else
7368a6c8 863 FD_SET(c->sock, writeset);
864}
5260325f 865
7368a6c8 866/*
867 * This is a special state for X11 authentication spoofing. An opened X11
868 * connection (when authentication spoofing is being done) remains in this
869 * state until the first packet has been completely read. The authentication
870 * data in that packet is then substituted by the real data if it matches the
871 * fake data, and the channel is put into normal mode.
0b242b12 872 * XXX All this happens at the client side.
8e7895b8 873 * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
7368a6c8 874 */
396c147e 875static int
8e7895b8 876x11_open_helper(Buffer *b)
7368a6c8 877{
1e3b8b07 878 u_char *ucp;
879 u_int proto_len, data_len;
5260325f 880
7368a6c8 881 /* Check if the fixed size part of the packet is in buffer. */
8e7895b8 882 if (buffer_len(b) < 12)
7368a6c8 883 return 0;
884
885 /* Parse the lengths of variable-length fields. */
20905a8e 886 ucp = buffer_ptr(b);
7368a6c8 887 if (ucp[0] == 0x42) { /* Byte order MSB first. */
888 proto_len = 256 * ucp[6] + ucp[7];
889 data_len = 256 * ucp[8] + ucp[9];
890 } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
891 proto_len = ucp[6] + 256 * ucp[7];
892 data_len = ucp[8] + 256 * ucp[9];
893 } else {
d7ac5f18 894 debug2("Initial X11 packet contains bad byte order byte: 0x%x",
184eed6a 895 ucp[0]);
7368a6c8 896 return -1;
897 }
5260325f 898
7368a6c8 899 /* Check if the whole packet is in buffer. */
8e7895b8 900 if (buffer_len(b) <
7368a6c8 901 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
902 return 0;
5260325f 903
7368a6c8 904 /* Check if authentication protocol matches. */
905 if (proto_len != strlen(x11_saved_proto) ||
906 memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
d7ac5f18 907 debug2("X11 connection uses different authentication protocol.");
7368a6c8 908 return -1;
909 }
910 /* Check if authentication data matches our fake data. */
911 if (data_len != x11_fake_data_len ||
912 memcmp(ucp + 12 + ((proto_len + 3) & ~3),
913 x11_fake_data, x11_fake_data_len) != 0) {
d7ac5f18 914 debug2("X11 auth data does not match fake data.");
7368a6c8 915 return -1;
916 }
917 /* Check fake data length */
918 if (x11_fake_data_len != x11_saved_data_len) {
919 error("X11 fake_data_len %d != saved_data_len %d",
920 x11_fake_data_len, x11_saved_data_len);
921 return -1;
922 }
923 /*
924 * Received authentication protocol and data match
925 * our fake data. Substitute the fake data with real
926 * data.
927 */
928 memcpy(ucp + 12 + ((proto_len + 3) & ~3),
929 x11_saved_data, x11_saved_data_len);
930 return 1;
931}
5260325f 932
396c147e 933static void
c8e9c167 934channel_pre_x11_open_13(Channel *c, fd_set *readset, fd_set *writeset)
7368a6c8 935{
8e7895b8 936 int ret = x11_open_helper(&c->output);
e1feb9bf 937
7368a6c8 938 if (ret == 1) {
939 /* Start normal processing for the channel. */
940 c->type = SSH_CHANNEL_OPEN;
a8be9f80 941 channel_pre_open_13(c, readset, writeset);
7368a6c8 942 } else if (ret == -1) {
943 /*
944 * We have received an X11 connection that has bad
945 * authentication information.
946 */
bbe88b6d 947 logit("X11 connection rejected because of wrong authentication.");
7368a6c8 948 buffer_clear(&c->input);
949 buffer_clear(&c->output);
489aa2e9 950 channel_close_fd(&c->sock);
7368a6c8 951 c->sock = -1;
952 c->type = SSH_CHANNEL_CLOSED;
953 packet_start(SSH_MSG_CHANNEL_CLOSE);
954 packet_put_int(c->remote_id);
955 packet_send();
956 }
957}
5260325f 958
396c147e 959static void
c8e9c167 960channel_pre_x11_open(Channel *c, fd_set *readset, fd_set *writeset)
7368a6c8 961{
8e7895b8 962 int ret = x11_open_helper(&c->output);
a5f82435 963
964 /* c->force_drain = 1; */
965
7368a6c8 966 if (ret == 1) {
967 c->type = SSH_CHANNEL_OPEN;
0c0738d5 968 channel_pre_open(c, readset, writeset);
7368a6c8 969 } else if (ret == -1) {
bbe88b6d 970 logit("X11 connection rejected because of wrong authentication.");
d7ac5f18 971 debug2("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
8341f420 972 chan_read_failed(c);
973 buffer_clear(&c->input);
974 chan_ibuf_empty(c);
975 buffer_clear(&c->output);
976 /* for proto v1, the peer will send an IEOF */
977 if (compat20)
978 chan_write_failed(c);
979 else
980 c->type = SSH_CHANNEL_OPEN;
d7ac5f18 981 debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
7368a6c8 982 }
983}
5260325f 984
28b9cb4d 985/* try to decode a socks4 header */
ebb90778 986/* ARGSUSED */
396c147e 987static int
c8e9c167 988channel_decode_socks4(Channel *c, fd_set *readset, fd_set *writeset)
0490e609 989{
661e45a0 990 char *p, *host;
4866a6d6 991 u_int len, have, i, found, need;
184eed6a 992 char username[256];
0490e609 993 struct {
994 u_int8_t version;
995 u_int8_t command;
996 u_int16_t dest_port;
28b9cb4d 997 struct in_addr dest_addr;
0490e609 998 } s4_req, s4_rsp;
999
28b9cb4d 1000 debug2("channel %d: decode socks4", c->self);
53b8fe68 1001
1002 have = buffer_len(&c->input);
1003 len = sizeof(s4_req);
1004 if (have < len)
1005 return 0;
1006 p = buffer_ptr(&c->input);
4866a6d6 1007
1008 need = 1;
1009 /* SOCKS4A uses an invalid IP address 0.0.0.x */
1010 if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1011 debug2("channel %d: socks4a request", c->self);
1012 /* ... and needs an extra string (the hostname) */
1013 need = 2;
1014 }
1015 /* Check for terminating NUL on the string(s) */
53b8fe68 1016 for (found = 0, i = len; i < have; i++) {
1017 if (p[i] == '\0') {
4866a6d6 1018 found++;
1019 if (found == need)
1020 break;
53b8fe68 1021 }
1022 if (i > 1024) {
1023 /* the peer is probably sending garbage */
1024 debug("channel %d: decode socks4: too long",
1025 c->self);
1026 return -1;
1027 }
1028 }
4866a6d6 1029 if (found < need)
53b8fe68 1030 return 0;
0490e609 1031 buffer_get(&c->input, (char *)&s4_req.version, 1);
1032 buffer_get(&c->input, (char *)&s4_req.command, 1);
1033 buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
28b9cb4d 1034 buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
53b8fe68 1035 have = buffer_len(&c->input);
0490e609 1036 p = buffer_ptr(&c->input);
1037 len = strlen(p);
6683b40f 1038 debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
4866a6d6 1039 len++; /* trailing '\0' */
0490e609 1040 if (len > have)
28b9cb4d 1041 fatal("channel %d: decode socks4: len %d > have %d",
0490e609 1042 c->self, len, have);
1043 strlcpy(username, p, sizeof(username));
1044 buffer_consume(&c->input, len);
0490e609 1045
1338ba77 1046 if (c->path != NULL) {
1047 xfree(c->path);
1048 c->path = NULL;
1049 }
4866a6d6 1050 if (need == 1) { /* SOCKS4: one string */
1051 host = inet_ntoa(s4_req.dest_addr);
1338ba77 1052 c->path = xstrdup(host);
4866a6d6 1053 } else { /* SOCKS4A: two strings */
1054 have = buffer_len(&c->input);
1055 p = buffer_ptr(&c->input);
1056 len = strlen(p);
1057 debug2("channel %d: decode socks4a: host %s/%d",
1058 c->self, p, len);
1059 len++; /* trailing '\0' */
1060 if (len > have)
1061 fatal("channel %d: decode socks4a: len %d > have %d",
1062 c->self, len, have);
1338ba77 1063 if (len > NI_MAXHOST) {
4866a6d6 1064 error("channel %d: hostname \"%.100s\" too long",
1065 c->self, p);
1066 return -1;
1067 }
1338ba77 1068 c->path = xstrdup(p);
4866a6d6 1069 buffer_consume(&c->input, len);
1070 }
0490e609 1071 c->host_port = ntohs(s4_req.dest_port);
184eed6a 1072
d7ac5f18 1073 debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
4866a6d6 1074 c->self, c->path, c->host_port, s4_req.command);
0490e609 1075
28b9cb4d 1076 if (s4_req.command != 1) {
4866a6d6 1077 debug("channel %d: cannot handle: %s cn %d",
1078 c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
28b9cb4d 1079 return -1;
0490e609 1080 }
28b9cb4d 1081 s4_rsp.version = 0; /* vn: 0 for reply */
1082 s4_rsp.command = 90; /* cd: req granted */
0490e609 1083 s4_rsp.dest_port = 0; /* ignored */
28b9cb4d 1084 s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
15dd2c4f 1085 buffer_append(&c->output, &s4_rsp, sizeof(s4_rsp));
28b9cb4d 1086 return 1;
0490e609 1087}
1088
f49658f5 1089/* try to decode a socks5 header */
1090#define SSH_SOCKS5_AUTHDONE 0x1000
1091#define SSH_SOCKS5_NOAUTH 0x00
1092#define SSH_SOCKS5_IPV4 0x01
1093#define SSH_SOCKS5_DOMAIN 0x03
1094#define SSH_SOCKS5_IPV6 0x04
1095#define SSH_SOCKS5_CONNECT 0x01
1096#define SSH_SOCKS5_SUCCESS 0x00
1097
ebb90778 1098/* ARGSUSED */
f49658f5 1099static int
c8e9c167 1100channel_decode_socks5(Channel *c, fd_set *readset, fd_set *writeset)
f49658f5 1101{
1102 struct {
1103 u_int8_t version;
1104 u_int8_t command;
1105 u_int8_t reserved;
1106 u_int8_t atyp;
1107 } s5_req, s5_rsp;
1108 u_int16_t dest_port;
1338ba77 1109 u_char *p, dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
a217e418 1110 u_int have, need, i, found, nmethods, addrlen, af;
f49658f5 1111
1112 debug2("channel %d: decode socks5", c->self);
1113 p = buffer_ptr(&c->input);
1114 if (p[0] != 0x05)
1115 return -1;
1116 have = buffer_len(&c->input);
1117 if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1118 /* format: ver | nmethods | methods */
aff51935 1119 if (have < 2)
f49658f5 1120 return 0;
1121 nmethods = p[1];
1122 if (have < nmethods + 2)
1123 return 0;
1124 /* look for method: "NO AUTHENTICATION REQUIRED" */
4f6e2ba9 1125 for (found = 0, i = 2; i < nmethods + 2; i++) {
d4f40d92 1126 if (p[i] == SSH_SOCKS5_NOAUTH) {
f49658f5 1127 found = 1;
1128 break;
1129 }
1130 }
1131 if (!found) {
1132 debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1133 c->self);
1134 return -1;
1135 }
1136 buffer_consume(&c->input, nmethods + 2);
1137 buffer_put_char(&c->output, 0x05); /* version */
1138 buffer_put_char(&c->output, SSH_SOCKS5_NOAUTH); /* method */
1139 FD_SET(c->sock, writeset);
1140 c->flags |= SSH_SOCKS5_AUTHDONE;
1141 debug2("channel %d: socks5 auth done", c->self);
1142 return 0; /* need more */
1143 }
1144 debug2("channel %d: socks5 post auth", c->self);
1145 if (have < sizeof(s5_req)+1)
1146 return 0; /* need more */
5b5f6af7 1147 memcpy(&s5_req, p, sizeof(s5_req));
f49658f5 1148 if (s5_req.version != 0x05 ||
1149 s5_req.command != SSH_SOCKS5_CONNECT ||
1150 s5_req.reserved != 0x00) {
d7ac5f18 1151 debug2("channel %d: only socks5 connect supported", c->self);
f49658f5 1152 return -1;
1153 }
f8cc7664 1154 switch (s5_req.atyp){
f49658f5 1155 case SSH_SOCKS5_IPV4:
1156 addrlen = 4;
1157 af = AF_INET;
1158 break;
1159 case SSH_SOCKS5_DOMAIN:
1160 addrlen = p[sizeof(s5_req)];
1161 af = -1;
1162 break;
1163 case SSH_SOCKS5_IPV6:
1164 addrlen = 16;
1165 af = AF_INET6;
1166 break;
1167 default:
d7ac5f18 1168 debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
f49658f5 1169 return -1;
1170 }
a217e418 1171 need = sizeof(s5_req) + addrlen + 2;
1172 if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1173 need++;
1174 if (have < need)
f49658f5 1175 return 0;
1176 buffer_consume(&c->input, sizeof(s5_req));
1177 if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1178 buffer_consume(&c->input, 1); /* host string length */
1179 buffer_get(&c->input, (char *)&dest_addr, addrlen);
1180 buffer_get(&c->input, (char *)&dest_port, 2);
1181 dest_addr[addrlen] = '\0';
1338ba77 1182 if (c->path != NULL) {
1183 xfree(c->path);
1184 c->path = NULL;
1185 }
1186 if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
920706fd 1187 if (addrlen >= NI_MAXHOST) {
1338ba77 1188 error("channel %d: dynamic request: socks5 hostname "
1189 "\"%.100s\" too long", c->self, dest_addr);
1190 return -1;
1191 }
1192 c->path = xstrdup(dest_addr);
1193 } else {
1194 if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1195 return -1;
1196 c->path = xstrdup(ntop);
1197 }
f49658f5 1198 c->host_port = ntohs(dest_port);
b6453d99 1199
d7ac5f18 1200 debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
f49658f5 1201 c->self, c->path, c->host_port, s5_req.command);
1202
1203 s5_rsp.version = 0x05;
1204 s5_rsp.command = SSH_SOCKS5_SUCCESS;
1205 s5_rsp.reserved = 0; /* ignored */
1206 s5_rsp.atyp = SSH_SOCKS5_IPV4;
1207 ((struct in_addr *)&dest_addr)->s_addr = INADDR_ANY;
1208 dest_port = 0; /* ignored */
1209
15dd2c4f 1210 buffer_append(&c->output, &s5_rsp, sizeof(s5_rsp));
1211 buffer_append(&c->output, &dest_addr, sizeof(struct in_addr));
1212 buffer_append(&c->output, &dest_port, sizeof(dest_port));
f49658f5 1213 return 1;
1214}
1215
28b9cb4d 1216/* dynamic port forwarding */
396c147e 1217static void
c8e9c167 1218channel_pre_dynamic(Channel *c, fd_set *readset, fd_set *writeset)
28b9cb4d 1219{
1220 u_char *p;
2ceb8101 1221 u_int have;
1222 int ret;
28b9cb4d 1223
1224 have = buffer_len(&c->input);
639cb8ab 1225 c->delayed = 0;
28b9cb4d 1226 debug2("channel %d: pre_dynamic: have %d", c->self, have);
070adba2 1227 /* buffer_dump(&c->input); */
28b9cb4d 1228 /* check if the fixed size part of the packet is in buffer. */
f49658f5 1229 if (have < 3) {
28b9cb4d 1230 /* need more */
1231 FD_SET(c->sock, readset);
1232 return;
1233 }
1234 /* try to guess the protocol */
1235 p = buffer_ptr(&c->input);
1236 switch (p[0]) {
6683b40f 1237 case 0x04:
1238 ret = channel_decode_socks4(c, readset, writeset);
1239 break;
f49658f5 1240 case 0x05:
1241 ret = channel_decode_socks5(c, readset, writeset);
1242 break;
28b9cb4d 1243 default:
1244 ret = -1;
1245 break;
1246 }
1247 if (ret < 0) {
719fc62f 1248 chan_mark_dead(c);
28b9cb4d 1249 } else if (ret == 0) {
1250 debug2("channel %d: pre_dynamic: need more", c->self);
1251 /* need more */
1252 FD_SET(c->sock, readset);
1253 } else {
1254 /* switch to the next state */
1255 c->type = SSH_CHANNEL_OPENING;
1256 port_open_helper(c, "direct-tcpip");
1257 }
1258}
0490e609 1259
7368a6c8 1260/* This is our fake X11 server socket. */
ebb90778 1261/* ARGSUSED */
396c147e 1262static void
c8e9c167 1263channel_post_x11_listener(Channel *c, fd_set *readset, fd_set *writeset)
7368a6c8 1264{
719fc62f 1265 Channel *nc;
9fb764ab 1266 struct sockaddr_storage addr;
bcc0381e 1267 int newsock;
7368a6c8 1268 socklen_t addrlen;
865ac82e 1269 char buf[16384], *remote_ipaddr;
0b242b12 1270 int remote_port;
7368a6c8 1271
1272 if (FD_ISSET(c->sock, readset)) {
1273 debug("X11 connection requested.");
1274 addrlen = sizeof(addr);
9fb764ab 1275 newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
ac151b18 1276 if (c->single_connection) {
d7ac5f18 1277 debug2("single_connection: closing X11 listener.");
ac151b18 1278 channel_close_fd(&c->sock);
1279 chan_mark_dead(c);
1280 }
7368a6c8 1281 if (newsock < 0) {
1282 error("accept: %.100s", strerror(errno));
1283 return;
5260325f 1284 }
bcc0381e 1285 set_nodelay(newsock);
865ac82e 1286 remote_ipaddr = get_peer_ipaddr(newsock);
0b242b12 1287 remote_port = get_peer_port(newsock);
7368a6c8 1288 snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
865ac82e 1289 remote_ipaddr, remote_port);
0b242b12 1290
719fc62f 1291 nc = channel_new("accepted x11 socket",
0b242b12 1292 SSH_CHANNEL_OPENING, newsock, newsock, -1,
0d942eff 1293 c->local_window_max, c->local_maxpacket, 0, buf, 1);
0b242b12 1294 if (compat20) {
1295 packet_start(SSH2_MSG_CHANNEL_OPEN);
1296 packet_put_cstring("x11");
719fc62f 1297 packet_put_int(nc->self);
ac151b18 1298 packet_put_int(nc->local_window_max);
1299 packet_put_int(nc->local_maxpacket);
865ac82e 1300 /* originator ipaddr and port */
1301 packet_put_cstring(remote_ipaddr);
d0c832f3 1302 if (datafellows & SSH_BUG_X11FWD) {
d7ac5f18 1303 debug2("ssh2 x11 bug compat mode");
d0c832f3 1304 } else {
1305 packet_put_int(remote_port);
1306 }
0b242b12 1307 packet_send();
1308 } else {
1309 packet_start(SSH_SMSG_X11_OPEN);
719fc62f 1310 packet_put_int(nc->self);
8e7895b8 1311 if (packet_get_protocol_flags() &
1312 SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
449c5ba5 1313 packet_put_cstring(buf);
0b242b12 1314 packet_send();
1315 }
865ac82e 1316 xfree(remote_ipaddr);
8efc0c15 1317 }
8efc0c15 1318}
1319
396c147e 1320static void
0490e609 1321port_open_helper(Channel *c, char *rtype)
1322{
1323 int direct;
1324 char buf[1024];
1325 char *remote_ipaddr = get_peer_ipaddr(c->sock);
29798ed0 1326 int remote_port = get_peer_port(c->sock);
0490e609 1327
1328 direct = (strcmp(rtype, "direct-tcpip") == 0);
1329
1330 snprintf(buf, sizeof buf,
1331 "%s: listening port %d for %.100s port %d, "
1332 "connect from %.200s port %d",
1333 rtype, c->listening_port, c->path, c->host_port,
1334 remote_ipaddr, remote_port);
1335
1336 xfree(c->remote_name);
1337 c->remote_name = xstrdup(buf);
1338
1339 if (compat20) {
1340 packet_start(SSH2_MSG_CHANNEL_OPEN);
1341 packet_put_cstring(rtype);
1342 packet_put_int(c->self);
1343 packet_put_int(c->local_window_max);
1344 packet_put_int(c->local_maxpacket);
1345 if (direct) {
1346 /* target host, port */
1347 packet_put_cstring(c->path);
1348 packet_put_int(c->host_port);
1349 } else {
1350 /* listen address, port */
1351 packet_put_cstring(c->path);
1352 packet_put_int(c->listening_port);
1353 }
1354 /* originator host and port */
1355 packet_put_cstring(remote_ipaddr);
29798ed0 1356 packet_put_int((u_int)remote_port);
0490e609 1357 packet_send();
1358 } else {
1359 packet_start(SSH_MSG_PORT_OPEN);
1360 packet_put_int(c->self);
1361 packet_put_cstring(c->path);
1362 packet_put_int(c->host_port);
8e7895b8 1363 if (packet_get_protocol_flags() &
1364 SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
0490e609 1365 packet_put_cstring(c->remote_name);
1366 packet_send();
1367 }
1368 xfree(remote_ipaddr);
1369}
1370
442aee3a 1371static void
1372channel_set_reuseaddr(int fd)
1373{
1374 int on = 1;
1375
1376 /*
1377 * Set socket options.
1378 * Allow local port reuse in TIME_WAIT.
1379 */
1380 if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
1381 error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
1382}
1383
aa3378df 1384/*
7368a6c8 1385 * This socket is listening for connections to a forwarded TCP/IP port.
aa3378df 1386 */
ebb90778 1387/* ARGSUSED */
396c147e 1388static void
c8e9c167 1389channel_post_port_listener(Channel *c, fd_set *readset, fd_set *writeset)
7368a6c8 1390{
0490e609 1391 Channel *nc;
9fb764ab 1392 struct sockaddr_storage addr;
719fc62f 1393 int newsock, nextstate;
7368a6c8 1394 socklen_t addrlen;
0490e609 1395 char *rtype;
fa08c86b 1396
7368a6c8 1397 if (FD_ISSET(c->sock, readset)) {
1398 debug("Connection to port %d forwarding "
1399 "to %.100s port %d requested.",
1400 c->listening_port, c->path, c->host_port);
0490e609 1401
639cb8ab 1402 if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1403 nextstate = SSH_CHANNEL_OPENING;
1404 rtype = "forwarded-tcpip";
1405 } else {
1406 if (c->host_port == 0) {
1407 nextstate = SSH_CHANNEL_DYNAMIC;
f3964cb9 1408 rtype = "dynamic-tcpip";
639cb8ab 1409 } else {
1410 nextstate = SSH_CHANNEL_OPENING;
1411 rtype = "direct-tcpip";
1412 }
1413 }
0490e609 1414
7368a6c8 1415 addrlen = sizeof(addr);
9fb764ab 1416 newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
7368a6c8 1417 if (newsock < 0) {
1418 error("accept: %.100s", strerror(errno));
1419 return;
1420 }
811a6342 1421 set_nodelay(newsock);
0d942eff 1422 nc = channel_new(rtype, nextstate, newsock, newsock, -1,
1423 c->local_window_max, c->local_maxpacket, 0, rtype, 1);
0490e609 1424 nc->listening_port = c->listening_port;
1425 nc->host_port = c->host_port;
1338ba77 1426 if (c->path != NULL)
1427 nc->path = xstrdup(c->path);
0490e609 1428
639cb8ab 1429 if (nextstate == SSH_CHANNEL_DYNAMIC) {
1430 /*
1431 * do not call the channel_post handler until
1432 * this flag has been reset by a pre-handler.
1433 * otherwise the FD_ISSET calls might overflow
1434 */
1435 nc->delayed = 1;
1436 } else {
0490e609 1437 port_open_helper(nc, rtype);
639cb8ab 1438 }
7368a6c8 1439 }
1440}
8efc0c15 1441
7368a6c8 1442/*
1443 * This is the authentication agent socket listening for connections from
1444 * clients.
1445 */
ebb90778 1446/* ARGSUSED */
396c147e 1447static void
c8e9c167 1448channel_post_auth_listener(Channel *c, fd_set *readset, fd_set *writeset)
8efc0c15 1449{
719fc62f 1450 Channel *nc;
1451 int newsock;
9fb764ab 1452 struct sockaddr_storage addr;
48e671d5 1453 socklen_t addrlen;
5260325f 1454
7368a6c8 1455 if (FD_ISSET(c->sock, readset)) {
1456 addrlen = sizeof(addr);
9fb764ab 1457 newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
7368a6c8 1458 if (newsock < 0) {
1459 error("accept from auth socket: %.100s", strerror(errno));
1460 return;
1461 }
719fc62f 1462 nc = channel_new("accepted auth socket",
fa08c86b 1463 SSH_CHANNEL_OPENING, newsock, newsock, -1,
1464 c->local_window_max, c->local_maxpacket,
0d942eff 1465 0, "accepted auth socket", 1);
fa08c86b 1466 if (compat20) {
1467 packet_start(SSH2_MSG_CHANNEL_OPEN);
1468 packet_put_cstring("auth-agent@openssh.com");
719fc62f 1469 packet_put_int(nc->self);
fa08c86b 1470 packet_put_int(c->local_window_max);
1471 packet_put_int(c->local_maxpacket);
1472 } else {
1473 packet_start(SSH_SMSG_AGENT_OPEN);
719fc62f 1474 packet_put_int(nc->self);
fa08c86b 1475 }
7368a6c8 1476 packet_send();
1477 }
1478}
5260325f 1479
ebb90778 1480/* ARGSUSED */
396c147e 1481static void
c8e9c167 1482channel_post_connecting(Channel *c, fd_set *readset, fd_set *writeset)
97fb6912 1483{
e07e21ad 1484 int err = 0, sock;
8ab2cb35 1485 socklen_t sz = sizeof(err);
d18e0850 1486
97fb6912 1487 if (FD_ISSET(c->sock, writeset)) {
db518d9b 1488 if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
d18e0850 1489 err = errno;
1490 error("getsockopt SO_ERROR failed");
1491 }
1492 if (err == 0) {
e07e21ad 1493 debug("channel %d: connected to %s port %d",
1494 c->self, c->connect_ctx.host, c->connect_ctx.port);
1495 channel_connect_ctx_free(&c->connect_ctx);
d18e0850 1496 c->type = SSH_CHANNEL_OPEN;
1497 if (compat20) {
1498 packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1499 packet_put_int(c->remote_id);
1500 packet_put_int(c->self);
1501 packet_put_int(c->local_window);
1502 packet_put_int(c->local_maxpacket);
1503 } else {
1504 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1505 packet_put_int(c->remote_id);
1506 packet_put_int(c->self);
1507 }
97fb6912 1508 } else {
e07e21ad 1509 debug("channel %d: connection failed: %s",
d18e0850 1510 c->self, strerror(err));
e07e21ad 1511 /* Try next address, if any */
1512 if ((sock = connect_next(&c->connect_ctx)) > 0) {
1513 close(c->sock);
1514 c->sock = c->rfd = c->wfd = sock;
1515 channel_max_fd = channel_find_maxfd();
1516 return;
1517 }
1518 /* Exhausted all addresses */
1519 error("connect_to %.100s port %d: failed.",
1520 c->connect_ctx.host, c->connect_ctx.port);
1521 channel_connect_ctx_free(&c->connect_ctx);
d18e0850 1522 if (compat20) {
1523 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1524 packet_put_int(c->remote_id);
1525 packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1526 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1527 packet_put_cstring(strerror(err));
1528 packet_put_cstring("");
1529 }
97fb6912 1530 } else {
d18e0850 1531 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1532 packet_put_int(c->remote_id);
97fb6912 1533 }
d18e0850 1534 chan_mark_dead(c);
97fb6912 1535 }
d18e0850 1536 packet_send();
97fb6912 1537 }
1538}
1539
ebb90778 1540/* ARGSUSED */
396c147e 1541static int
c8e9c167 1542channel_handle_rfd(Channel *c, fd_set *readset, fd_set *writeset)
7368a6c8 1543{
fa1d7d85 1544 char buf[CHAN_RBUF];
bd6a1355 1545 int len, force;
7368a6c8 1546
bd6a1355 1547 force = c->isatty && c->detach_close && c->istate != CHAN_INPUT_CLOSED;
1548 if (c->rfd != -1 && (force || FD_ISSET(c->rfd, readset))) {
ea8c44d9 1549 errno = 0;
7368a6c8 1550 len = read(c->rfd, buf, sizeof(buf));
5a0c8771 1551 if (len < 0 && (errno == EINTR ||
1552 ((errno == EAGAIN || errno == EWOULDBLOCK) && !force)))
0fbe8c74 1553 return 1;
ea8c44d9 1554#ifndef PTY_ZEROREAD
7368a6c8 1555 if (len <= 0) {
ea8c44d9 1556#else
9c04d67d 1557 if ((!c->isatty && len <= 0) ||
1558 (c->isatty && (len < 0 || (len == 0 && errno != 0)))) {
ea8c44d9 1559#endif
d7ac5f18 1560 debug2("channel %d: read<=0 rfd %d len %d",
7368a6c8 1561 c->self, c->rfd, len);
28b9cb4d 1562 if (c->type != SSH_CHANNEL_OPEN) {
d7ac5f18 1563 debug2("channel %d: not open", c->self);
719fc62f 1564 chan_mark_dead(c);
0490e609 1565 return -1;
28b9cb4d 1566 } else if (compat13) {
9c50edcf 1567 buffer_clear(&c->output);
7368a6c8 1568 c->type = SSH_CHANNEL_INPUT_DRAINING;
d7ac5f18 1569 debug2("channel %d: input draining.", c->self);
7368a6c8 1570 } else {
1571 chan_read_failed(c);
5260325f 1572 }
7368a6c8 1573 return -1;
1574 }
6aacefa7 1575 if (c->input_filter != NULL) {
2e73a022 1576 if (c->input_filter(c, buf, len) == -1) {
d7ac5f18 1577 debug2("channel %d: filter stops", c->self);
2e73a022 1578 chan_read_failed(c);
1579 }
d20f3c9e 1580 } else if (c->datagram) {
1581 buffer_put_string(&c->input, buf, len);
2e73a022 1582 } else {
1583 buffer_append(&c->input, buf, len);
1584 }
7368a6c8 1585 }
1586 return 1;
1587}
a7137f6b 1588
ebb90778 1589/* ARGSUSED */
396c147e 1590static int
c8e9c167 1591channel_handle_wfd(Channel *c, fd_set *readset, fd_set *writeset)
7368a6c8 1592{
95ce5599 1593 struct termios tio;
c1c6a032 1594 u_char *data = NULL, *buf;
780a9951 1595 u_int dlen;
7368a6c8 1596 int len;
1597
1598 /* Send buffered output data to the socket. */
6fd8622b 1599 if (c->wfd != -1 &&
7368a6c8 1600 FD_ISSET(c->wfd, writeset) &&
1601 buffer_len(&c->output) > 0) {
c1c6a032 1602 if (c->output_filter != NULL) {
1603 if ((buf = c->output_filter(c, &data, &dlen)) == NULL) {
1604 debug2("channel %d: filter stops", c->self);
d7b37427 1605 if (c->type != SSH_CHANNEL_OPEN)
1606 chan_mark_dead(c);
1607 else
1608 chan_write_failed(c);
1609 return -1;
c1c6a032 1610 }
1611 } else if (c->datagram) {
1612 buf = data = buffer_get_string(&c->output, &dlen);
1613 } else {
1614 buf = data = buffer_ptr(&c->output);
1615 dlen = buffer_len(&c->output);
1616 }
1617
d20f3c9e 1618 if (c->datagram) {
d20f3c9e 1619 /* ignore truncated writes, datagrams might get lost */
1620 c->local_consumed += dlen + 4;
c1c6a032 1621 len = write(c->wfd, buf, dlen);
d20f3c9e 1622 xfree(data);
5a0c8771 1623 if (len < 0 && (errno == EINTR || errno == EAGAIN ||
1624 errno == EWOULDBLOCK))
d20f3c9e 1625 return 1;
1626 if (len <= 0) {
1627 if (c->type != SSH_CHANNEL_OPEN)
1628 chan_mark_dead(c);
1629 else
1630 chan_write_failed(c);
1631 return -1;
1632 }
1633 return 1;
1634 }
64c0ce80 1635#ifdef _AIX
aff51935 1636 /* XXX: Later AIX versions can't push as much data to tty */
7fbb4189 1637 if (compat20 && c->wfd_isatty)
1638 dlen = MIN(dlen, 8*1024);
64c0ce80 1639#endif
c1c6a032 1640
1641 len = write(c->wfd, buf, dlen);
5a0c8771 1642 if (len < 0 &&
1643 (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK))
0fbe8c74 1644 return 1;
7368a6c8 1645 if (len <= 0) {
28b9cb4d 1646 if (c->type != SSH_CHANNEL_OPEN) {
d7ac5f18 1647 debug2("channel %d: not open", c->self);
719fc62f 1648 chan_mark_dead(c);
28b9cb4d 1649 return -1;
1650 } else if (compat13) {
9c50edcf 1651 buffer_clear(&c->output);
d7ac5f18 1652 debug2("channel %d: input draining.", c->self);
7368a6c8 1653 c->type = SSH_CHANNEL_INPUT_DRAINING;
1654 } else {
1655 chan_write_failed(c);
5260325f 1656 }
7368a6c8 1657 return -1;
1658 }
5e934f78 1659#ifndef BROKEN_TCGETATTR_ICANON
c1c6a032 1660 if (compat20 && c->isatty && dlen >= 1 && buf[0] != '\r') {
0ae4fe1d 1661 if (tcgetattr(c->wfd, &tio) == 0 &&
1662 !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1663 /*
1664 * Simulate echo to reduce the impact of
355724fc 1665 * traffic analysis. We need to match the
95ce5599 1666 * size of a SSH2_MSG_CHANNEL_DATA message
c1c6a032 1667 * (4 byte channel id + buf)
0ae4fe1d 1668 */
95ce5599 1669 packet_send_ignore(4 + len);
0ae4fe1d 1670 packet_send();
0ae4fe1d 1671 }
1672 }
5e934f78 1673#endif
7368a6c8 1674 buffer_consume(&c->output, len);
7e7327a1 1675 if (compat20 && len > 0) {
1676 c->local_consumed += len;
1677 }
1678 }
1679 return 1;
1680}
a7137f6b 1681
396c147e 1682static int
c8e9c167 1683channel_handle_efd(Channel *c, fd_set *readset, fd_set *writeset)
7e7327a1 1684{
fa1d7d85 1685 char buf[CHAN_RBUF];
7e7327a1 1686 int len;
1687
8ce64345 1688/** XXX handle drain efd, too */
7e7327a1 1689 if (c->efd != -1) {
1690 if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1691 FD_ISSET(c->efd, writeset) &&
1692 buffer_len(&c->extended) > 0) {
1693 len = write(c->efd, buffer_ptr(&c->extended),
1694 buffer_len(&c->extended));
de273eef 1695 debug2("channel %d: written %d to efd %d",
7e7327a1 1696 c->self, len, c->efd);
5a0c8771 1697 if (len < 0 && (errno == EINTR || errno == EAGAIN ||
1698 errno == EWOULDBLOCK))
ee55dacf 1699 return 1;
1700 if (len <= 0) {
1701 debug2("channel %d: closing write-efd %d",
1702 c->self, c->efd);
489aa2e9 1703 channel_close_fd(&c->efd);
ee55dacf 1704 } else {
7e7327a1 1705 buffer_consume(&c->extended, len);
1706 c->local_consumed += len;
1707 }
1708 } else if (c->extended_usage == CHAN_EXTENDED_READ &&
34640ce6 1709 (c->detach_close || FD_ISSET(c->efd, readset))) {
7e7327a1 1710 len = read(c->efd, buf, sizeof(buf));
de273eef 1711 debug2("channel %d: read %d from efd %d",
184eed6a 1712 c->self, len, c->efd);
5a0c8771 1713 if (len < 0 && (errno == EINTR || ((errno == EAGAIN ||
1714 errno == EWOULDBLOCK) && !c->detach_close)))
ee55dacf 1715 return 1;
1716 if (len <= 0) {
1717 debug2("channel %d: closing read-efd %d",
8ce64345 1718 c->self, c->efd);
489aa2e9 1719 channel_close_fd(&c->efd);
ee55dacf 1720 } else {
7e7327a1 1721 buffer_append(&c->extended, buf, len);
ee55dacf 1722 }
7e7327a1 1723 }
1724 }
1725 return 1;
1726}
a7137f6b 1727
ebb90778 1728/* ARGSUSED */
396c147e 1729static int
c8e9c167 1730channel_handle_ctl(Channel *c, fd_set *readset, fd_set *writeset)
5e96b616 1731{
1732 char buf[16];
1733 int len;
1734
1735 /* Monitor control fd to detect if the slave client exits */
1736 if (c->ctl_fd != -1 && FD_ISSET(c->ctl_fd, readset)) {
1737 len = read(c->ctl_fd, buf, sizeof(buf));
5a0c8771 1738 if (len < 0 &&
1739 (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK))
5e96b616 1740 return 1;
1741 if (len <= 0) {
1742 debug2("channel %d: ctl read<=0", c->self);
1743 if (c->type != SSH_CHANNEL_OPEN) {
1744 debug2("channel %d: not open", c->self);
1745 chan_mark_dead(c);
1746 return -1;
1747 } else {
1748 chan_read_failed(c);
1749 chan_write_failed(c);
1750 }
1751 return -1;
1752 } else
1753 fatal("%s: unexpected data on ctl fd", __func__);
1754 }
1755 return 1;
1756}
a7137f6b 1757
5e96b616 1758static int
ee55dacf 1759channel_check_window(Channel *c)
7e7327a1 1760{
28b9cb4d 1761 if (c->type == SSH_CHANNEL_OPEN &&
1762 !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
d9245683 1763 ((c->local_window_max - c->local_window >
68a73f53 1764 c->local_maxpacket*3) ||
1765 c->local_window < c->local_window_max/2) &&
7e7327a1 1766 c->local_consumed > 0) {
1767 packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1768 packet_put_int(c->remote_id);
1769 packet_put_int(c->local_consumed);
1770 packet_send();
de273eef 1771 debug2("channel %d: window %d sent adjust %d",
7e7327a1 1772 c->self, c->local_window,
1773 c->local_consumed);
1774 c->local_window += c->local_consumed;
1775 c->local_consumed = 0;
7368a6c8 1776 }
1777 return 1;
1778}
5260325f 1779
396c147e 1780static void
c8e9c167 1781channel_post_open(Channel *c, fd_set *readset, fd_set *writeset)
7368a6c8 1782{
639cb8ab 1783 if (c->delayed)
1784 return;
7368a6c8 1785 channel_handle_rfd(c, readset, writeset);
1786 channel_handle_wfd(c, readset, writeset);
0c0738d5 1787 if (!compat20)
639cb8ab 1788 return;
7e7327a1 1789 channel_handle_efd(c, readset, writeset);
5e96b616 1790 channel_handle_ctl(c, readset, writeset);
ee55dacf 1791 channel_check_window(c);
7e7327a1 1792}
1793
ebb90778 1794/* ARGSUSED */
396c147e 1795static void
c8e9c167 1796channel_post_output_drain_13(Channel *c, fd_set *readset, fd_set *writeset)
7368a6c8 1797{
1798 int len;
e1feb9bf 1799
7368a6c8 1800 /* Send buffered output data to the socket. */
1801 if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
1802 len = write(c->sock, buffer_ptr(&c->output),
1803 buffer_len(&c->output));
1804 if (len <= 0)
9c50edcf 1805 buffer_clear(&c->output);
7368a6c8 1806 else
1807 buffer_consume(&c->output, len);
1808 }
1809}
5260325f 1810
396c147e 1811static void
7e7327a1 1812channel_handler_init_20(void)
1813{
0c0738d5 1814 channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
0b242b12 1815 channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
7e7327a1 1816 channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
fa08c86b 1817 channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
0b242b12 1818 channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
fa08c86b 1819 channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
97fb6912 1820 channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
0490e609 1821 channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
7e7327a1 1822
0c0738d5 1823 channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
7e7327a1 1824 channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
fa08c86b 1825 channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
0b242b12 1826 channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
fa08c86b 1827 channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
97fb6912 1828 channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
0c0738d5 1829 channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
7e7327a1 1830}
1831
396c147e 1832static void
7368a6c8 1833channel_handler_init_13(void)
1834{
1835 channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
1836 channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
1837 channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1838 channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1839 channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1840 channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
1841 channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
97fb6912 1842 channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
0490e609 1843 channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
7368a6c8 1844
0c0738d5 1845 channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
7368a6c8 1846 channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1847 channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1848 channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1849 channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
97fb6912 1850 channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
0c0738d5 1851 channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
7368a6c8 1852}
5260325f 1853
396c147e 1854static void
7368a6c8 1855channel_handler_init_15(void)
1856{
0c0738d5 1857 channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
0b242b12 1858 channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
7368a6c8 1859 channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1860 channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1861 channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
97fb6912 1862 channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
0490e609 1863 channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
7368a6c8 1864
1865 channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1866 channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1867 channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
0c0738d5 1868 channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
97fb6912 1869 channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
0c0738d5 1870 channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
7368a6c8 1871}
1872
396c147e 1873static void
7368a6c8 1874channel_handler_init(void)
1875{
1876 int i;
e1feb9bf 1877
184eed6a 1878 for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
7368a6c8 1879 channel_pre[i] = NULL;
1880 channel_post[i] = NULL;
1881 }
7e7327a1 1882 if (compat20)
1883 channel_handler_init_20();
1884 else if (compat13)
7368a6c8 1885 channel_handler_init_13();
1886 else
1887 channel_handler_init_15();
1888}
1889
418e724c 1890/* gc dead channels */
1891static void
1892channel_garbage_collect(Channel *c)
1893{
1894 if (c == NULL)
1895 return;
1896 if (c->detach_user != NULL) {
8cd0437d 1897 if (!chan_is_dead(c, c->detach_close))
418e724c 1898 return;
d7ac5f18 1899 debug2("channel %d: gc: notify user", c->self);
418e724c 1900 c->detach_user(c->self, NULL);
1901 /* if we still have a callback */
1902 if (c->detach_user != NULL)
1903 return;
d7ac5f18 1904 debug2("channel %d: gc: user detached", c->self);
418e724c 1905 }
1906 if (!chan_is_dead(c, 1))
1907 return;
d7ac5f18 1908 debug2("channel %d: garbage collecting", c->self);
418e724c 1909 channel_free(c);
1910}
1911
396c147e 1912static void
c8e9c167 1913channel_handler(chan_fn *ftab[], fd_set *readset, fd_set *writeset)
7368a6c8 1914{
1915 static int did_init = 0;
9a995072 1916 u_int i;
7368a6c8 1917 Channel *c;
1918
1919 if (!did_init) {
1920 channel_handler_init();
1921 did_init = 1;
1922 }
1923 for (i = 0; i < channels_alloc; i++) {
719fc62f 1924 c = channels[i];
1925 if (c == NULL)
5260325f 1926 continue;
6fd8622b 1927 if (ftab[c->type] != NULL)
1928 (*ftab[c->type])(c, readset, writeset);
418e724c 1929 channel_garbage_collect(c);
8efc0c15 1930 }
8efc0c15 1931}
1932
8e7895b8 1933/*
1934 * Allocate/update select bitmasks and add any bits relevant to channels in
1935 * select bitmasks.
1936 */
6ae2364d 1937void
c422989b 1938channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
9a995072 1939 u_int *nallocp, int rekeying)
7368a6c8 1940{
c5d10563 1941 u_int n, sz, nfdset;
39929cdb 1942
1943 n = MAX(*maxfdp, channel_max_fd);
1944
c5d10563 1945 nfdset = howmany(n+1, NFDBITS);
1946 /* Explicitly test here, because xrealloc isn't always called */
1947 if (nfdset && SIZE_T_MAX / nfdset < sizeof(fd_mask))
1948 fatal("channel_prepare_select: max_fd (%d) is too large", n);
1949 sz = nfdset * sizeof(fd_mask);
1950
489aa2e9 1951 /* perhaps check sz < nalloc/2 and shrink? */
1952 if (*readsetp == NULL || sz > *nallocp) {
c5d10563 1953 *readsetp = xrealloc(*readsetp, nfdset, sizeof(fd_mask));
1954 *writesetp = xrealloc(*writesetp, nfdset, sizeof(fd_mask));
489aa2e9 1955 *nallocp = sz;
39929cdb 1956 }
489aa2e9 1957 *maxfdp = n;
39929cdb 1958 memset(*readsetp, 0, sz);
1959 memset(*writesetp, 0, sz);
1960
c422989b 1961 if (!rekeying)
1962 channel_handler(channel_pre, *readsetp, *writesetp);
7368a6c8 1963}
1964
8e7895b8 1965/*
1966 * After select, perform any appropriate operations for channels which have
1967 * events pending.
1968 */
6ae2364d 1969void
c8e9c167 1970channel_after_select(fd_set *readset, fd_set *writeset)
7368a6c8 1971{
1972 channel_handler(channel_post, readset, writeset);
1973}
1974
8e7895b8 1975
39929cdb 1976/* If there is data to send to the connection, enqueue some of it now. */
6ae2364d 1977void
d5bb9418 1978channel_output_poll(void)
8efc0c15 1979{
7368a6c8 1980 Channel *c;
9a995072 1981 u_int i, len;
5260325f 1982
1983 for (i = 0; i < channels_alloc; i++) {
719fc62f 1984 c = channels[i];
1985 if (c == NULL)
1986 continue;
48e671d5 1987
8e7895b8 1988 /*
1989 * We are only interested in channels that can have buffered
1990 * incoming data.
1991 */
48e671d5 1992 if (compat13) {
7368a6c8 1993 if (c->type != SSH_CHANNEL_OPEN &&
1994 c->type != SSH_CHANNEL_INPUT_DRAINING)
48e671d5 1995 continue;
1996 } else {
7368a6c8 1997 if (c->type != SSH_CHANNEL_OPEN)
48e671d5 1998 continue;
48e671d5 1999 }
e78a59f5 2000 if (compat20 &&
2001 (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
ee55dacf 2002 /* XXX is this true? */
418e724c 2003 debug3("channel %d: will not send data after close", c->self);
7e7327a1 2004 continue;
2005 }
5260325f 2006
2007 /* Get the amount of buffered data for this channel. */
ee55dacf 2008 if ((c->istate == CHAN_INPUT_OPEN ||
2009 c->istate == CHAN_INPUT_WAIT_DRAIN) &&
2010 (len = buffer_len(&c->input)) > 0) {
d20f3c9e 2011 if (c->datagram) {
2012 if (len > 0) {
2013 u_char *data;
2014 u_int dlen;
2015
2016 data = buffer_get_string(&c->input,
2017 &dlen);
2018 packet_start(SSH2_MSG_CHANNEL_DATA);
2019 packet_put_int(c->remote_id);
2020 packet_put_string(data, dlen);
2021 packet_send();
2022 c->remote_window -= dlen + 4;
2023 xfree(data);
2024 }
2025 continue;
2026 }
8e7895b8 2027 /*
2028 * Send some data for the other side over the secure
2029 * connection.
2030 */
7e7327a1 2031 if (compat20) {
2032 if (len > c->remote_window)
2033 len = c->remote_window;
2034 if (len > c->remote_maxpacket)
2035 len = c->remote_maxpacket;
5260325f 2036 } else {
7e7327a1 2037 if (packet_is_interactive()) {
2038 if (len > 1024)
2039 len = 512;
2040 } else {
2041 /* Keep the packets at reasonable size. */
2042 if (len > packet_get_maxsize()/2)
2043 len = packet_get_maxsize()/2;
2044 }
5260325f 2045 }
7368a6c8 2046 if (len > 0) {
7e7327a1 2047 packet_start(compat20 ?
2048 SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
7368a6c8 2049 packet_put_int(c->remote_id);
2050 packet_put_string(buffer_ptr(&c->input), len);
2051 packet_send();
2052 buffer_consume(&c->input, len);
2053 c->remote_window -= len;
7368a6c8 2054 }
2055 } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
5260325f 2056 if (compat13)
2057 fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
aa3378df 2058 /*
2059 * input-buffer is empty and read-socket shutdown:
d2296ed7 2060 * tell peer, that we will not send more data: send IEOF.
2061 * hack for extended data: delay EOF if EFD still in use.
aa3378df 2062 */
d2296ed7 2063 if (CHANNEL_EFD_INPUT_ACTIVE(c))
4e2e5cfd 2064 debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
2065 c->self, c->efd, buffer_len(&c->extended));
d2296ed7 2066 else
2067 chan_ibuf_empty(c);
5260325f 2068 }
7e7327a1 2069 /* Send extended data, i.e. stderr */
2070 if (compat20 &&
d2296ed7 2071 !(c->flags & CHAN_EOF_SENT) &&
7e7327a1 2072 c->remote_window > 0 &&
2073 (len = buffer_len(&c->extended)) > 0 &&
2074 c->extended_usage == CHAN_EXTENDED_READ) {
f91d9a89 2075 debug2("channel %d: rwin %u elen %u euse %d",
ee55dacf 2076 c->self, c->remote_window, buffer_len(&c->extended),
2077 c->extended_usage);
7e7327a1 2078 if (len > c->remote_window)
2079 len = c->remote_window;
2080 if (len > c->remote_maxpacket)
2081 len = c->remote_maxpacket;
2082 packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
2083 packet_put_int(c->remote_id);
2084 packet_put_int(SSH2_EXTENDED_DATA_STDERR);
2085 packet_put_string(buffer_ptr(&c->extended), len);
2086 packet_send();
2087 buffer_consume(&c->extended, len);
2088 c->remote_window -= len;
ee55dacf 2089 debug2("channel %d: sent ext data %d", c->self, len);
7e7327a1 2090 }
8efc0c15 2091 }
8efc0c15 2092}
2093
8e7895b8 2094
2095/* -- protocol input */
04aa9e67 2096
2097/* ARGSUSED */
6ae2364d 2098void
7819b5c3 2099channel_input_data(int type, u_int32_t seq, void *ctxt)
8efc0c15 2100{
48e671d5 2101 int id;
5260325f 2102 char *data;
1e3b8b07 2103 u_int data_len;
7368a6c8 2104 Channel *c;
5260325f 2105
2106 /* Get the channel number and verify it. */
48e671d5 2107 id = packet_get_int();
7368a6c8 2108 c = channel_lookup(id);
2109 if (c == NULL)
48e671d5 2110 packet_disconnect("Received data for nonexistent channel %d.", id);
5260325f 2111
2112 /* Ignore any data for non-open channels (might happen on close) */
7368a6c8 2113 if (c->type != SSH_CHANNEL_OPEN &&
2114 c->type != SSH_CHANNEL_X11_OPEN)
48e671d5 2115 return;
2116
5260325f 2117 /* Get the data. */
17f02f0a 2118 data = packet_get_string_ptr(&data_len);
7368a6c8 2119
7741e239 2120 /*
2121 * Ignore data for protocol > 1.3 if output end is no longer open.
2122 * For protocol 2 the sending side is reducing its window as it sends
2123 * data, so we must 'fake' consumption of the data in order to ensure
2124 * that window updates are sent back. Otherwise the connection might
2125 * deadlock.
2126 */
2127 if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) {
2128 if (compat20) {
2129 c->local_window -= data_len;
2130 c->local_consumed += data_len;
2131 }
7741e239 2132 return;
2133 }
2134
6aacefa7 2135 if (compat20) {
7e7327a1 2136 if (data_len > c->local_maxpacket) {
bbe88b6d 2137 logit("channel %d: rcvd big packet %d, maxpack %d",
7e7327a1 2138 c->self, data_len, c->local_maxpacket);
2139 }
2140 if (data_len > c->local_window) {
bbe88b6d 2141 logit("channel %d: rcvd too much data %d, win %d",
7e7327a1 2142 c->self, data_len, c->local_window);
7e7327a1 2143 return;
2144 }
2145 c->local_window -= data_len;
7e7327a1 2146 }
d20f3c9e 2147 if (c->datagram)
2148 buffer_put_string(&c->output, data, data_len);
2149 else
2150 buffer_append(&c->output, data, data_len);
17f02f0a 2151 packet_check_eom();
8efc0c15 2152}
8e7895b8 2153
04aa9e67 2154/* ARGSUSED */
6ae2364d 2155void
7819b5c3 2156channel_input_extended_data(int type, u_int32_t seq, void *ctxt)
7e7327a1 2157{
2158 int id;
7e7327a1 2159 char *data;
a594fa74 2160 u_int data_len, tcode;
7e7327a1 2161 Channel *c;
2162
2163 /* Get the channel number and verify it. */
2164 id = packet_get_int();
2165 c = channel_lookup(id);
2166
2167 if (c == NULL)
2168 packet_disconnect("Received extended_data for bad channel %d.", id);
2169 if (c->type != SSH_CHANNEL_OPEN) {
bbe88b6d 2170 logit("channel %d: ext data for non open", id);
7e7327a1 2171 return;
2172 }
d2296ed7 2173 if (c->flags & CHAN_EOF_RCVD) {
2174 if (datafellows & SSH_BUG_EXTEOF)
2175 debug("channel %d: accepting ext data after eof", id);
2176 else
2177 packet_disconnect("Received extended_data after EOF "
2178 "on channel %d.", id);
2179 }
7e7327a1 2180 tcode = packet_get_int();
2181 if (c->efd == -1 ||
2182 c->extended_usage != CHAN_EXTENDED_WRITE ||
2183 tcode != SSH2_EXTENDED_DATA_STDERR) {
bbe88b6d 2184 logit("channel %d: bad ext data", c->self);
7e7327a1 2185 return;
2186 }
2187 data = packet_get_string(&data_len);
95500969 2188 packet_check_eom();
7e7327a1 2189 if (data_len > c->local_window) {
bbe88b6d 2190 logit("channel %d: rcvd too much extended_data %d, win %d",
7e7327a1 2191 c->self, data_len, c->local_window);
2192 xfree(data);
2193 return;
2194 }
de273eef 2195 debug2("channel %d: rcvd ext data %d", c->self, data_len);
7e7327a1 2196 c->local_window -= data_len;
2197 buffer_append(&c->extended, data, data_len);
2198 xfree(data);
2199}
2200
04aa9e67 2201/* ARGSUSED */
6ae2364d 2202void
7819b5c3 2203channel_input_ieof(int type, u_int32_t seq, void *ctxt)
7368a6c8 2204{
2205 int id;
2206 Channel *c;
2207
7368a6c8 2208 id = packet_get_int();
95500969 2209 packet_check_eom();
7368a6c8 2210 c = channel_lookup(id);
2211 if (c == NULL)
2212 packet_disconnect("Received ieof for nonexistent channel %d.", id);
2213 chan_rcvd_ieof(c);
a5f82435 2214
2215 /* XXX force input close */
8341f420 2216 if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
a5f82435 2217 debug("channel %d: FORCE input drain", c->self);
2218 c->istate = CHAN_INPUT_WAIT_DRAIN;
32e7d71f 2219 if (buffer_len(&c->input) == 0)
2220 chan_ibuf_empty(c);
a5f82435 2221 }
2222
7368a6c8 2223}
8efc0c15 2224
04aa9e67 2225/* ARGSUSED */
6ae2364d 2226void
7819b5c3 2227channel_input_close(int type, u_int32_t seq, void *ctxt)
8efc0c15 2228{
7368a6c8 2229 int id;
2230 Channel *c;
5260325f 2231
7368a6c8 2232 id = packet_get_int();
95500969 2233 packet_check_eom();
7368a6c8 2234 c = channel_lookup(id);
2235 if (c == NULL)
2236 packet_disconnect("Received close for nonexistent channel %d.", id);
aa3378df 2237
2238 /*
2239 * Send a confirmation that we have closed the channel and no more
2240 * data is coming for it.
2241 */
5260325f 2242 packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
7368a6c8 2243 packet_put_int(c->remote_id);
5260325f 2244 packet_send();
2245
aa3378df 2246 /*
2247 * If the channel is in closed state, we have sent a close request,
2248 * and the other side will eventually respond with a confirmation.
2249 * Thus, we cannot free the channel here, because then there would be
2250 * no-one to receive the confirmation. The channel gets freed when
2251 * the confirmation arrives.
2252 */
7368a6c8 2253 if (c->type != SSH_CHANNEL_CLOSED) {
aa3378df 2254 /*
2255 * Not a closed channel - mark it as draining, which will
2256 * cause it to be freed later.
2257 */
9c50edcf 2258 buffer_clear(&c->input);
7368a6c8 2259 c->type = SSH_CHANNEL_OUTPUT_DRAINING;
5260325f 2260 }
8efc0c15 2261}
2262
7368a6c8 2263/* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
04aa9e67 2264/* ARGSUSED */
6ae2364d 2265void
7819b5c3 2266channel_input_oclose(int type, u_int32_t seq, void *ctxt)
8efc0c15 2267{
7368a6c8 2268 int id = packet_get_int();
2269 Channel *c = channel_lookup(id);
a8a21a53 2270
95500969 2271 packet_check_eom();
7368a6c8 2272 if (c == NULL)
2273 packet_disconnect("Received oclose for nonexistent channel %d.", id);
2274 chan_rcvd_oclose(c);
8efc0c15 2275}
2276
04aa9e67 2277/* ARGSUSED */
6ae2364d 2278void
7819b5c3 2279channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt)
7368a6c8 2280{
2281 int id = packet_get_int();
2282 Channel *c = channel_lookup(id);
2283
95500969 2284 packet_check_eom();
7368a6c8 2285 if (c == NULL)
2286 packet_disconnect("Received close confirmation for "
2287 "out-of-range channel %d.", id);
2288 if (c->type != SSH_CHANNEL_CLOSED)
2289 packet_disconnect("Received close confirmation for "
2290 "non-closed channel %d (type %d).", id, c->type);
719fc62f 2291 channel_free(c);
7368a6c8 2292}
8efc0c15 2293
04aa9e67 2294/* ARGSUSED */
6ae2364d 2295void
7819b5c3 2296channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt)
8efc0c15 2297{
7368a6c8 2298 int id, remote_id;
2299 Channel *c;
5260325f 2300
7368a6c8 2301 id = packet_get_int();
2302 c = channel_lookup(id);
5260325f 2303
7368a6c8 2304 if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2305 packet_disconnect("Received open confirmation for "
2306 "non-opening channel %d.", id);
2307 remote_id = packet_get_int();
aa3378df 2308 /* Record the remote channel number and mark that the channel is now open. */
7368a6c8 2309 c->remote_id = remote_id;
2310 c->type = SSH_CHANNEL_OPEN;
7e7327a1 2311
2312 if (compat20) {
2313 c->remote_window = packet_get_int();
2314 c->remote_maxpacket = packet_get_int();
3593bdc0 2315 if (c->open_confirm) {
de273eef 2316 debug2("callback start");
3593bdc0 2317 c->open_confirm(c->self, c->open_confirm_ctx);
de273eef 2318 debug2("callback done");
7e7327a1 2319 }
d7ac5f18 2320 debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
7e7327a1 2321 c->remote_window, c->remote_maxpacket);
2322 }
95500969 2323 packet_check_eom();
8efc0c15 2324}
2325
396c147e 2326static char *
d18e0850 2327reason2txt(int reason)
2328{
6aacefa7 2329 switch (reason) {
d18e0850 2330 case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
2331 return "administratively prohibited";
2332 case SSH2_OPEN_CONNECT_FAILED:
2333 return "connect failed";
2334 case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
2335 return "unknown channel type";
2336 case SSH2_OPEN_RESOURCE_SHORTAGE:
2337 return "resource shortage";
2338 }
7e8c18e9 2339 return "unknown reason";
d18e0850 2340}
2341
04aa9e67 2342/* ARGSUSED */
6ae2364d 2343void
7819b5c3 2344channel_input_open_failure(int type, u_int32_t seq, void *ctxt)
8efc0c15 2345{
02a024dd 2346 int id, reason;
2347 char *msg = NULL, *lang = NULL;
7368a6c8 2348 Channel *c;
5260325f 2349
7368a6c8 2350 id = packet_get_int();
2351 c = channel_lookup(id);
2352
2353 if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2354 packet_disconnect("Received open failure for "
2355 "non-opening channel %d.", id);
7e7327a1 2356 if (compat20) {
02a024dd 2357 reason = packet_get_int();
fbe90f7b 2358 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
02a024dd 2359 msg = packet_get_string(NULL);
2360 lang = packet_get_string(NULL);
2361 }
bbe88b6d 2362 logit("channel %d: open failed: %s%s%s", id,
d18e0850 2363 reason2txt(reason), msg ? ": ": "", msg ? msg : "");
02a024dd 2364 if (msg != NULL)
2365 xfree(msg);
2366 if (lang != NULL)
2367 xfree(lang);
7e7327a1 2368 }
95500969 2369 packet_check_eom();
6cf44b6a 2370 /* Schedule the channel for cleanup/deletion. */
2371 chan_mark_dead(c);
8efc0c15 2372}
2373
04aa9e67 2374/* ARGSUSED */
8e7895b8 2375void
7819b5c3 2376channel_input_window_adjust(int type, u_int32_t seq, void *ctxt)
8e7895b8 2377{
2378 Channel *c;
f91d9a89 2379 int id;
2380 u_int adjust;
3ffc6336 2381
8e7895b8 2382 if (!compat20)
2383 return;
8efc0c15 2384
8e7895b8 2385 /* Get the channel number and verify it. */
2386 id = packet_get_int();
2387 c = channel_lookup(id);
2388
b872f7f0 2389 if (c == NULL) {
2390 logit("Received window adjust for non-open channel %d.", id);
8e7895b8 2391 return;
2392 }
2393 adjust = packet_get_int();
95500969 2394 packet_check_eom();
f91d9a89 2395 debug2("channel %d: rcvd adjust %u", id, adjust);
8e7895b8 2396 c->remote_window += adjust;
2397}
2398
04aa9e67 2399/* ARGSUSED */
8e7895b8 2400void
7819b5c3 2401channel_input_port_open(int type, u_int32_t seq, void *ctxt)
8efc0c15 2402{
8e7895b8 2403 Channel *c = NULL;
2404 u_short host_port;
2405 char *host, *originator_string;
e07e21ad 2406 int remote_id;
5260325f 2407
8e7895b8 2408 remote_id = packet_get_int();
2409 host = packet_get_string(NULL);
2410 host_port = packet_get_int();
2411
2412 if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
2413 originator_string = packet_get_string(NULL);
2414 } else {
2415 originator_string = xstrdup("unknown (remote did not supply name)");
2416 }
95500969 2417 packet_check_eom();
e07e21ad 2418 c = channel_connect_to(host, host_port,
2419 "connected socket", originator_string);
0d942eff 2420 xfree(originator_string);
e07e21ad 2421 xfree(host);
8e7895b8 2422 if (c == NULL) {
2423 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2424 packet_put_int(remote_id);
2425 packet_send();
e07e21ad 2426 } else
2427 c->remote_id = remote_id;
8efc0c15 2428}
2429
3593bdc0 2430/* ARGSUSED */
2431void
2432channel_input_status_confirm(int type, u_int32_t seq, void *ctxt)
2433{
2434 Channel *c;
2435 struct channel_confirm *cc;
b09b559d 2436 int id;
3593bdc0 2437
2438 /* Reset keepalive timeout */
dc1f1948 2439 packet_set_alive_timeouts(0);
3593bdc0 2440
b09b559d 2441 id = packet_get_int();
3593bdc0 2442 packet_check_eom();
2443
b09b559d 2444 debug2("channel_input_status_confirm: type %d id %d", type, id);
3593bdc0 2445
b09b559d 2446 if ((c = channel_lookup(id)) == NULL) {
2447 logit("channel_input_status_confirm: %d: unknown", id);
3593bdc0 2448 return;
2449 }
2450 ;
2451 if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
2452 return;
2453 cc->cb(type, c, cc->ctx);
2454 TAILQ_REMOVE(&c->status_confirms, cc, entry);
2455 bzero(cc, sizeof(*cc));
2456 xfree(cc);
2457}
8e7895b8 2458
2459/* -- tcp forwarding */
2460
5e4a7219 2461void
2462channel_set_af(int af)
2463{
2464 IPv4or6 = af;
2465}
2466
fe7dba42 2467void
2468channel_set_rdomain(int rdomain)
2469{
2470 channel_rdomain = rdomain;
2471}
2472
5641aefa 2473static int
17525a70 2474channel_setup_fwd_listener(int type, const char *listen_addr,
2475 u_short listen_port, int *allocated_listen_port,
5641aefa 2476 const char *host_to_connect, u_short port_to_connect, int gateway_ports)
8efc0c15 2477{
719fc62f 2478 Channel *c;
442aee3a 2479 int sock, r, success = 0, wildcard = 0, is_client;
48e671d5 2480 struct addrinfo hints, *ai, *aitop;
3867aa0a 2481 const char *host, *addr;
5641aefa 2482 char ntop[NI_MAXHOST], strport[NI_MAXSERV];
17525a70 2483 in_port_t *lport_p;
5260325f 2484
5641aefa 2485 host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
2486 listen_addr : host_to_connect;
3867aa0a 2487 is_client = (type == SSH_CHANNEL_PORT_LISTENER);
02a024dd 2488
5641aefa 2489 if (host == NULL) {
2490 error("No forward host name.");
38946c65 2491 return 0;
fa08c86b 2492 }
920706fd 2493 if (strlen(host) >= NI_MAXHOST) {
02a024dd 2494 error("Forward host name too long.");
38946c65 2495 return 0;
02a024dd 2496 }
5260325f 2497
3867aa0a 2498 /*
2499 * Determine whether or not a port forward listens to loopback,
f8cc7664 2500 * specified address or wildcard. On the client, a specified bind
2501 * address will always override gateway_ports. On the server, a
2502 * gateway_ports of 1 (``yes'') will override the client's
2503 * specification and force a wildcard bind, whereas a value of 2
2504 * (``clientspecified'') will bind to whatever address the client
3867aa0a 2505 * asked for.
2506 *
2507 * Special-case listen_addrs are:
2508 *
2509 * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
2510 * "" (empty string), "*" -> wildcard v4/v6
2511 * "localhost" -> loopback v4/v6
2512 */
2513 addr = NULL;
2514 if (listen_addr == NULL) {
2515 /* No address specified: default to gateway_ports setting */
2516 if (gateway_ports)
2517 wildcard = 1;
2518 } else if (gateway_ports || is_client) {
2519 if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
bc4cc956 2520 strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
3867aa0a 2521 *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
2522 (!is_client && gateway_ports == 1))
2523 wildcard = 1;
2524 else if (strcmp(listen_addr, "localhost") != 0)
2525 addr = listen_addr;
2526 }
2527
2528 debug3("channel_setup_fwd_listener: type %d wildcard %d addr %s",
2529 type, wildcard, (addr == NULL) ? "NULL" : addr);
2530
aa3378df 2531 /*
48e671d5 2532 * getaddrinfo returns a loopback address if the hostname is
2533 * set to NULL and hints.ai_flags is not AI_PASSIVE
aa3378df 2534 */
48e671d5 2535 memset(&hints, 0, sizeof(hints));
2536 hints.ai_family = IPv4or6;
3867aa0a 2537 hints.ai_flags = wildcard ? AI_PASSIVE : 0;
48e671d5 2538 hints.ai_socktype = SOCK_STREAM;
fa08c86b 2539 snprintf(strport, sizeof strport, "%d", listen_port);
3867aa0a 2540 if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
2541 if (addr == NULL) {
2542 /* This really shouldn't happen */
2543 packet_disconnect("getaddrinfo: fatal error: %s",
bb4626fe 2544 ssh_gai_strerror(r));
3867aa0a 2545 } else {
38946c65 2546 error("channel_setup_fwd_listener: "
bb4626fe 2547 "getaddrinfo(%.64s): %s", addr,
2548 ssh_gai_strerror(r));
3867aa0a 2549 }
38946c65 2550 return 0;
3867aa0a 2551 }
17525a70 2552 if (allocated_listen_port != NULL)
2553 *allocated_listen_port = 0;
48e671d5 2554 for (ai = aitop; ai; ai = ai->ai_next) {
17525a70 2555 switch (ai->ai_family) {
2556 case AF_INET:
2557 lport_p = &((struct sockaddr_in *)ai->ai_addr)->
2558 sin_port;
2559 break;
2560 case AF_INET6:
2561 lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
2562 sin6_port;
2563 break;
2564 default:
48e671d5 2565 continue;
17525a70 2566 }
2567 /*
2568 * If allocating a port for -R forwards, then use the
2569 * same port for all address families.
2570 */
2571 if (type == SSH_CHANNEL_RPORT_LISTENER && listen_port == 0 &&
2572 allocated_listen_port != NULL && *allocated_listen_port > 0)
2573 *lport_p = htons(*allocated_listen_port);
2574
48e671d5 2575 if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2576 strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
5641aefa 2577 error("channel_setup_fwd_listener: getnameinfo failed");
48e671d5 2578 continue;
2579 }
2580 /* Create a port to listen for the host. */
fe7dba42 2581 sock = socket_rdomain(ai->ai_family, ai->ai_socktype,
2582 ai->ai_protocol, channel_rdomain);
48e671d5 2583 if (sock < 0) {
2584 /* this is no error since kernel may not support ipv6 */
2585 verbose("socket: %.100s", strerror(errno));
2586 continue;
2587 }
442aee3a 2588
2589 channel_set_reuseaddr(sock);
4e1082aa 2590 if (ai->ai_family == AF_INET6)
2591 sock_set_v6only(sock);
facfd613 2592
17525a70 2593 debug("Local forwarding listening on %s port %s.",
2594 ntop, strport);
48e671d5 2595
2596 /* Bind the socket to the address. */
2597 if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2598 /* address can be in use ipv6 address is already bound */
16218745 2599 if (!ai->ai_next)
2600 error("bind: %.100s", strerror(errno));
2601 else
2602 verbose("bind: %.100s", strerror(errno));
2b87da3b 2603
48e671d5 2604 close(sock);
2605 continue;
2606 }
2607 /* Start listening for connections on the socket. */
fce39749 2608 if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
48e671d5 2609 error("listen: %.100s", strerror(errno));
2610 close(sock);
2611 continue;
2612 }
17525a70 2613
2614 /*
2615 * listen_port == 0 requests a dynamically allocated port -
2616 * record what we got.
2617 */
2618 if (type == SSH_CHANNEL_RPORT_LISTENER && listen_port == 0 &&
2619 allocated_listen_port != NULL &&
2620 *allocated_listen_port == 0) {
2621 *allocated_listen_port = get_sock_port(sock, 1);
2622 debug("Allocated listen port %d",
2623 *allocated_listen_port);
2624 }
2625
48e671d5 2626 /* Allocate a channel number for the socket. */
8e7895b8 2627 c = channel_new("port listener", type, sock, sock, -1,
0b242b12 2628 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
0d942eff 2629 0, "port listener", 1);
1338ba77 2630 c->path = xstrdup(host);
719fc62f 2631 c->host_port = port_to_connect;
2632 c->listening_port = listen_port;
48e671d5 2633 success = 1;
2634 }
2635 if (success == 0)
5641aefa 2636 error("channel_setup_fwd_listener: cannot listen to port: %d",
02a024dd 2637 listen_port);
48e671d5 2638 freeaddrinfo(aitop);
02a024dd 2639 return success;
5260325f 2640}
8efc0c15 2641
d740ec16 2642int
2643channel_cancel_rport_listener(const char *host, u_short port)
2644{
9a995072 2645 u_int i;
2646 int found = 0;
d740ec16 2647
f8cc7664 2648 for (i = 0; i < channels_alloc; i++) {
d740ec16 2649 Channel *c = channels[i];
2650
2651 if (c != NULL && c->type == SSH_CHANNEL_RPORT_LISTENER &&
1338ba77 2652 strcmp(c->path, host) == 0 && c->listening_port == port) {
2912cbd6 2653 debug2("%s: close channel %d", __func__, i);
d740ec16 2654 channel_free(c);
2655 found = 1;
2656 }
2657 }
2658
2659 return (found);
2660}
2661
5641aefa 2662/* protocol local port fwd, used by ssh (and sshd in v1) */
2663int
3867aa0a 2664channel_setup_local_fwd_listener(const char *listen_host, u_short listen_port,
5641aefa 2665 const char *host_to_connect, u_short port_to_connect, int gateway_ports)
2666{
2667 return channel_setup_fwd_listener(SSH_CHANNEL_PORT_LISTENER,
17525a70 2668 listen_host, listen_port, NULL, host_to_connect, port_to_connect,
3867aa0a 2669 gateway_ports);
5641aefa 2670}
2671
2672/* protocol v2 remote port fwd, used by sshd */
2673int
2674channel_setup_remote_fwd_listener(const char *listen_address,
17525a70 2675 u_short listen_port, int *allocated_listen_port, int gateway_ports)
5641aefa 2676{
2677 return channel_setup_fwd_listener(SSH_CHANNEL_RPORT_LISTENER,
17525a70 2678 listen_address, listen_port, allocated_listen_port,
2679 NULL, 0, gateway_ports);
5641aefa 2680}
2681
aa3378df 2682/*
2683 * Initiate forwarding of connections to port "port" on remote host through
2684 * the secure channel to host:port from local side.
2685 */
8efc0c15 2686
42ea6f5e 2687int
3867aa0a 2688channel_request_remote_forwarding(const char *listen_host, u_short listen_port,
fa08c86b 2689 const char *host_to_connect, u_short port_to_connect)
8efc0c15 2690{
54a5250f 2691 int type, success = 0;
fa08c86b 2692
5260325f 2693 /* Record locally that connection to this host/port is permitted. */
2694 if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2695 fatal("channel_request_remote_forwarding: too many forwards");
2696
5260325f 2697 /* Send the forward request to the remote side. */
7e7327a1 2698 if (compat20) {
3867aa0a 2699 const char *address_to_bind;
04efe9b0 2700 if (listen_host == NULL) {
2701 if (datafellows & SSH_BUG_RFWD_ADDR)
2702 address_to_bind = "127.0.0.1";
2703 else
2704 address_to_bind = "localhost";
2705 } else if (*listen_host == '\0' ||
2706 strcmp(listen_host, "*") == 0) {
2707 if (datafellows & SSH_BUG_RFWD_ADDR)
2708 address_to_bind = "0.0.0.0";
2709 else
2710 address_to_bind = "";
2711 } else
3867aa0a 2712 address_to_bind = listen_host;
2713
7e7327a1 2714 packet_start(SSH2_MSG_GLOBAL_REQUEST);
2715 packet_put_cstring("tcpip-forward");
e0ae8728 2716 packet_put_char(1); /* boolean: want reply */
7e7327a1 2717 packet_put_cstring(address_to_bind);
2718 packet_put_int(listen_port);
fa08c86b 2719 packet_send();
2720 packet_write_wait();
2721 /* Assume that server accepts the request */
2722 success = 1;
7e7327a1 2723 } else {
2724 packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
7e7327a1 2725 packet_put_int(listen_port);
d6f24e45 2726 packet_put_cstring(host_to_connect);
2727 packet_put_int(port_to_connect);
7e7327a1 2728 packet_send();
2729 packet_write_wait();
fa08c86b 2730
2731 /* Wait for response from the remote side. */
54a5250f 2732 type = packet_read();
fa08c86b 2733 switch (type) {
2734 case SSH_SMSG_SUCCESS:
2735 success = 1;
2736 break;
2737 case SSH_SMSG_FAILURE:
fa08c86b 2738 break;
2739 default:
2740 /* Unknown packet */
2741 packet_disconnect("Protocol error for port forward request:"
2742 "received packet type %d.", type);
2743 }
2744 }
2745 if (success) {
2746 permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
2747 permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
2748 permitted_opens[num_permitted_opens].listen_port = listen_port;
2749 num_permitted_opens++;
7e7327a1 2750 }
42ea6f5e 2751 return (success ? 0 : -1);
8efc0c15 2752}
2753
d740ec16 2754/*
f2107e97 2755 * Request cancellation of remote forwarding of connection host:port from
d740ec16 2756 * local side.
2757 */
d740ec16 2758void
3867aa0a 2759channel_request_rforward_cancel(const char *host, u_short port)
d740ec16 2760{
2761 int i;
d740ec16 2762
2763 if (!compat20)
2764 return;
2765
2766 for (i = 0; i < num_permitted_opens; i++) {
f2107e97 2767 if (permitted_opens[i].host_to_connect != NULL &&
d740ec16 2768 permitted_opens[i].listen_port == port)
2769 break;
2770 }
2771 if (i >= num_permitted_opens) {
2772 debug("%s: requested forward not found", __func__);
2773 return;
2774 }
2775 packet_start(SSH2_MSG_GLOBAL_REQUEST);
2776 packet_put_cstring("cancel-tcpip-forward");
2777 packet_put_char(0);
3867aa0a 2778 packet_put_cstring(host == NULL ? "" : host);
d740ec16 2779 packet_put_int(port);
2780 packet_send();
2781
2782 permitted_opens[i].listen_port = 0;
2783 permitted_opens[i].port_to_connect = 0;
8c4bd764 2784 xfree(permitted_opens[i].host_to_connect);
d740ec16 2785 permitted_opens[i].host_to_connect = NULL;
2786}
2787
aa3378df 2788/*
2789 * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
2790 * listening for the port, and sends back a success reply (or disconnect
42ea6f5e 2791 * message if there was an error).
aa3378df 2792 */
42ea6f5e 2793int
1d1ffb87 2794channel_input_port_forward_request(int is_root, int gateway_ports)
8efc0c15 2795{
57112b5a 2796 u_short port, host_port;
42ea6f5e 2797 int success = 0;
5260325f 2798 char *hostname;
2799
2800 /* Get arguments from the packet. */
2801 port = packet_get_int();
2802 hostname = packet_get_string(NULL);
2803 host_port = packet_get_int();
2804
3c62e7eb 2805#ifndef HAVE_CYGWIN
aa3378df 2806 /*
2807 * Check that an unprivileged user is not trying to forward a
2808 * privileged port.
2809 */
5260325f 2810 if (port < IPPORT_RESERVED && !is_root)
8e7c9afc 2811 packet_disconnect(
2812 "Requested forwarding of port %d but user is not root.",
2813 port);
2814 if (host_port == 0)
2815 packet_disconnect("Dynamic forwarding denied.");
3c62e7eb 2816#endif
8e7c9afc 2817
fa08c86b 2818 /* Initiate forwarding */
42ea6f5e 2819 success = channel_setup_local_fwd_listener(NULL, port, hostname,
3867aa0a 2820 host_port, gateway_ports);
5260325f 2821
2822 /* Free the argument string. */
2823 xfree(hostname);
42ea6f5e 2824
2825 return (success ? 0 : -1);
8efc0c15 2826}
2827
01794848 2828/*
2829 * Permits opening to any host/port if permitted_opens[] is empty. This is
2830 * usually called by the server, because the user could connect to any port
2831 * anyway, and the server has no way to know but to trust the client anyway.
2832 */
2833void
d5bb9418 2834channel_permit_all_opens(void)
01794848 2835{
2836 if (num_permitted_opens == 0)
2837 all_opens_permitted = 1;
2838}
2839
cd332296 2840void
01794848 2841channel_add_permitted_opens(char *host, int port)
2842{
2843 if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
42ea6f5e 2844 fatal("channel_add_permitted_opens: too many forwards");
01794848 2845 debug("allow port forwarding to host %s port %d", host, port);
2846
2847 permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
2848 permitted_opens[num_permitted_opens].port_to_connect = port;
2849 num_permitted_opens++;
2850
2851 all_opens_permitted = 0;
2852}
2853
ea46e550 2854int
2fefbadf 2855channel_add_adm_permitted_opens(char *host, int port)
2856{
2857 if (num_adm_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2858 fatal("channel_add_adm_permitted_opens: too many forwards");
ea46e550 2859 debug("config allows port forwarding to host %s port %d", host, port);
2fefbadf 2860
2861 permitted_adm_opens[num_adm_permitted_opens].host_to_connect
2862 = xstrdup(host);
2863 permitted_adm_opens[num_adm_permitted_opens].port_to_connect = port;
ea46e550 2864 return ++num_adm_permitted_opens;
2fefbadf 2865}
2866
cd332296 2867void
01794848 2868channel_clear_permitted_opens(void)
2869{
2870 int i;
2871
2872 for (i = 0; i < num_permitted_opens; i++)
d740ec16 2873 if (permitted_opens[i].host_to_connect != NULL)
2874 xfree(permitted_opens[i].host_to_connect);
01794848 2875 num_permitted_opens = 0;
2fefbadf 2876}
2877
2878void
2879channel_clear_adm_permitted_opens(void)
2880{
2881 int i;
01794848 2882
2fefbadf 2883 for (i = 0; i < num_adm_permitted_opens; i++)
2884 if (permitted_adm_opens[i].host_to_connect != NULL)
2885 xfree(permitted_adm_opens[i].host_to_connect);
2886 num_adm_permitted_opens = 0;
01794848 2887}
2888
1760c982 2889void
2890channel_print_adm_permitted_opens(void)
2891{
cdfbc829 2892 int i;
1760c982 2893
68405671 2894 printf("permitopen");
861e9e53 2895 if (num_adm_permitted_opens == 0) {
68405671 2896 printf(" any\n");
861e9e53 2897 return;
2898 }
1760c982 2899 for (i = 0; i < num_adm_permitted_opens; i++)
2900 if (permitted_adm_opens[i].host_to_connect != NULL)
2901 printf(" %s:%d", permitted_adm_opens[i].host_to_connect,
2902 permitted_adm_opens[i].port_to_connect);
68405671 2903 printf("\n");
1760c982 2904}
2905
e07e21ad 2906/* Try to start non-blocking connect to next host in cctx list */
396c147e 2907static int
e07e21ad 2908connect_next(struct channel_connect *cctx)
8efc0c15 2909{
e07e21ad 2910 int sock, saved_errno;
48e671d5 2911 char ntop[NI_MAXHOST], strport[NI_MAXSERV];
48e671d5 2912
e07e21ad 2913 for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
2914 if (cctx->ai->ai_family != AF_INET &&
2915 cctx->ai->ai_family != AF_INET6)
48e671d5 2916 continue;
e07e21ad 2917 if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
2918 ntop, sizeof(ntop), strport, sizeof(strport),
2919 NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
2920 error("connect_next: getnameinfo failed");
48e671d5 2921 continue;
5260325f 2922 }
fe7dba42 2923 if ((sock = socket_rdomain(cctx->ai->ai_family,
2924 cctx->ai->ai_socktype, cctx->ai->ai_protocol,
2925 channel_rdomain)) == -1) {
e07e21ad 2926 if (cctx->ai->ai_next == NULL)
4940c411 2927 error("socket: %.100s", strerror(errno));
2928 else
2929 verbose("socket: %.100s", strerror(errno));
48e671d5 2930 continue;
5260325f 2931 }
170694d7 2932 if (set_nonblock(sock) == -1)
2933 fatal("%s: set_nonblock(%d)", __func__, sock);
e07e21ad 2934 if (connect(sock, cctx->ai->ai_addr,
2935 cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
2936 debug("connect_next: host %.100s ([%.100s]:%s): "
2937 "%.100s", cctx->host, ntop, strport,
48e671d5 2938 strerror(errno));
e07e21ad 2939 saved_errno = errno;
48e671d5 2940 close(sock);
e07e21ad 2941 errno = saved_errno;
2b87da3b 2942 continue; /* fail -- try next */
48e671d5 2943 }
e07e21ad 2944 debug("connect_next: host %.100s ([%.100s]:%s) "
2945 "in progress, fd=%d", cctx->host, ntop, strport, sock);
2946 cctx->ai = cctx->ai->ai_next;
2947 set_nodelay(sock);
2948 return sock;
2949 }
2950 return -1;
2951}
2952
2953static void
2954channel_connect_ctx_free(struct channel_connect *cctx)
2955{
2956 xfree(cctx->host);
2957 if (cctx->aitop)
2958 freeaddrinfo(cctx->aitop);
2959 bzero(cctx, sizeof(*cctx));
2960 cctx->host = NULL;
2961 cctx->ai = cctx->aitop = NULL;
2962}
2963
2964/* Return CONNECTING channel to remote host, port */
2965static Channel *
2966connect_to(const char *host, u_short port, char *ctype, char *rname)
2967{
2968 struct addrinfo hints;
2969 int gaierr;
2970 int sock = -1;
2971 char strport[NI_MAXSERV];
2972 struct channel_connect cctx;
2973 Channel *c;
5260325f 2974
267d5589 2975 memset(&cctx, 0, sizeof(cctx));
e07e21ad 2976 memset(&hints, 0, sizeof(hints));
2977 hints.ai_family = IPv4or6;
2978 hints.ai_socktype = SOCK_STREAM;
2979 snprintf(strport, sizeof strport, "%d", port);
2980 if ((gaierr = getaddrinfo(host, strport, &hints, &cctx.aitop)) != 0) {
2981 error("connect_to %.100s: unknown host (%s)", host,
2982 ssh_gai_strerror(gaierr));
2983 return NULL;
5260325f 2984 }
e07e21ad 2985
2986 cctx.host = xstrdup(host);
2987 cctx.port = port;
2988 cctx.ai = cctx.aitop;
2989
2990 if ((sock = connect_next(&cctx)) == -1) {
2991 error("connect to %.100s port %d failed: %s",
2992 host, port, strerror(errno));
2993 channel_connect_ctx_free(&cctx);
2994 return NULL;
8efc0c15 2995 }
e07e21ad 2996 c = channel_new(ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
2997 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
2998 c->connect_ctx = cctx;
2999 return c;
7368a6c8 3000}
01794848 3001
e07e21ad 3002Channel *
3003channel_connect_by_listen_address(u_short listen_port, char *ctype, char *rname)
fa08c86b 3004{
3005 int i;
01794848 3006
e07e21ad 3007 for (i = 0; i < num_permitted_opens; i++) {
d740ec16 3008 if (permitted_opens[i].host_to_connect != NULL &&
e07e21ad 3009 permitted_opens[i].listen_port == listen_port) {
01794848 3010 return connect_to(
fa08c86b 3011 permitted_opens[i].host_to_connect,
e07e21ad 3012 permitted_opens[i].port_to_connect, ctype, rname);
3013 }
3014 }
0b6fbf03 3015 error("WARNING: Server requests forwarding for unknown listen_port %d",
3016 listen_port);
e07e21ad 3017 return NULL;
fa08c86b 3018}
48e671d5 3019
01794848 3020/* Check if connecting to that port is permitted and connect. */
e07e21ad 3021Channel *
3022channel_connect_to(const char *host, u_short port, char *ctype, char *rname)
01794848 3023{
2fefbadf 3024 int i, permit, permit_adm = 1;
01794848 3025
3026 permit = all_opens_permitted;
3027 if (!permit) {
3028 for (i = 0; i < num_permitted_opens; i++)
d740ec16 3029 if (permitted_opens[i].host_to_connect != NULL &&
3030 permitted_opens[i].port_to_connect == port &&
01794848 3031 strcmp(permitted_opens[i].host_to_connect, host) == 0)
3032 permit = 1;
2fefbadf 3033 }
01794848 3034
2fefbadf 3035 if (num_adm_permitted_opens > 0) {
3036 permit_adm = 0;
3037 for (i = 0; i < num_adm_permitted_opens; i++)
3038 if (permitted_adm_opens[i].host_to_connect != NULL &&
3039 permitted_adm_opens[i].port_to_connect == port &&
3040 strcmp(permitted_adm_opens[i].host_to_connect, host)
3041 == 0)
3042 permit_adm = 1;
01794848 3043 }
2fefbadf 3044
3045 if (!permit || !permit_adm) {
bbe88b6d 3046 logit("Received request to connect to host %.100s port %d, "
01794848 3047 "but the request was denied.", host, port);
e07e21ad 3048 return NULL;
01794848 3049 }
e07e21ad 3050 return connect_to(host, port, ctype, rname);
01794848 3051}
3052
5e96b616 3053void
3054channel_send_window_changes(void)
3055{
9a995072 3056 u_int i;
5e96b616 3057 struct winsize ws;
3058
3059 for (i = 0; i < channels_alloc; i++) {
f8cc7664 3060 if (channels[i] == NULL || !channels[i]->client_tty ||
5e96b616 3061 channels[i]->type != SSH_CHANNEL_OPEN)
3062 continue;
3063 if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
3064 continue;
3065 channel_request_start(i, "window-change", 0);
148de80c 3066 packet_put_int((u_int)ws.ws_col);
3067 packet_put_int((u_int)ws.ws_row);
3068 packet_put_int((u_int)ws.ws_xpixel);
3069 packet_put_int((u_int)ws.ws_ypixel);
5e96b616 3070 packet_send();
3071 }
3072}
3073
8e7895b8 3074/* -- X11 forwarding */
8efc0c15 3075
aa3378df 3076/*
3077 * Creates an internet domain socket for listening for X11 connections.
57f228e8 3078 * Returns 0 and a suitable display number for the DISPLAY variable
3079 * stored in display_numberp , or -1 if an error occurs.
aa3378df 3080 */
c9d0ad9b 3081int
e6e573bd 3082x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
d08341e6 3083 int single_connection, u_int *display_numberp, int **chanids)
8efc0c15 3084{
ac151b18 3085 Channel *nc = NULL;
57112b5a 3086 int display_number, sock;
3087 u_short port;
48e671d5 3088 struct addrinfo hints, *ai, *aitop;
3089 char strport[NI_MAXSERV];
3090 int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
5260325f 3091
59e5aff5 3092 if (chanids == NULL)
3093 return -1;
3094
95f1eccc 3095 for (display_number = x11_display_offset;
184eed6a 3096 display_number < MAX_DISPLAYS;
3097 display_number++) {
5260325f 3098 port = 6000 + display_number;
48e671d5 3099 memset(&hints, 0, sizeof(hints));
3100 hints.ai_family = IPv4or6;
e6e573bd 3101 hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
48e671d5 3102 hints.ai_socktype = SOCK_STREAM;
3103 snprintf(strport, sizeof strport, "%d", port);
3104 if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
bb4626fe 3105 error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
c9d0ad9b 3106 return -1;
5260325f 3107 }
48e671d5 3108 for (ai = aitop; ai; ai = ai->ai_next) {
3109 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
3110 continue;
fe7dba42 3111 sock = socket_rdomain(ai->ai_family, ai->ai_socktype,
3112 ai->ai_protocol, channel_rdomain);
48e671d5 3113 if (sock < 0) {
4ee81249 3114 if ((errno != EINVAL) && (errno != EAFNOSUPPORT)) {
80a44451 3115 error("socket: %.100s", strerror(errno));
0ea89f7e 3116 freeaddrinfo(aitop);
c9d0ad9b 3117 return -1;
80a44451 3118 } else {
22d89d24 3119 debug("x11_create_display_inet: Socket family %d not supported",
3120 ai->ai_family);
80a44451 3121 continue;
3122 }
48e671d5 3123 }
4e1082aa 3124 if (ai->ai_family == AF_INET6)
3125 sock_set_v6only(sock);
554ebbed 3126 if (x11_use_localhost)
3127 channel_set_reuseaddr(sock);
48e671d5 3128 if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
d7ac5f18 3129 debug2("bind port %d: %.100s", port, strerror(errno));
48e671d5 3130 close(sock);
16218745 3131
48e671d5 3132 for (n = 0; n < num_socks; n++) {
48e671d5 3133 close(socks[n]);
3134 }
3135 num_socks = 0;
3136 break;
3137 }
3138 socks[num_socks++] = sock;
3139 if (num_socks == NUM_SOCKS)
3140 break;
5260325f 3141 }
4ccb01d6 3142 freeaddrinfo(aitop);
48e671d5 3143 if (num_socks > 0)
3144 break;
5260325f 3145 }
3146 if (display_number >= MAX_DISPLAYS) {
3147 error("Failed to allocate internet-domain X11 display socket.");
c9d0ad9b 3148 return -1;
8efc0c15 3149 }
5260325f 3150 /* Start listening for connections on the socket. */
48e671d5 3151 for (n = 0; n < num_socks; n++) {
3152 sock = socks[n];
fce39749 3153 if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
48e671d5 3154 error("listen: %.100s", strerror(errno));
48e671d5 3155 close(sock);
c9d0ad9b 3156 return -1;
a7effaac 3157 }
a7effaac 3158 }
5260325f 3159
48e671d5 3160 /* Allocate a channel for each socket. */
52e3daed 3161 *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
48e671d5 3162 for (n = 0; n < num_socks; n++) {
3163 sock = socks[n];
ac151b18 3164 nc = channel_new("x11 listener",
0b242b12 3165 SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
3166 CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
0d942eff 3167 0, "X11 inet listener", 1);
3a0d3d54 3168 nc->single_connection = single_connection;
59e5aff5 3169 (*chanids)[n] = nc->self;
48e671d5 3170 }
59e5aff5 3171 (*chanids)[n] = -1;
5260325f 3172
c9d0ad9b 3173 /* Return the display number for the DISPLAY environment variable. */
57f228e8 3174 *display_numberp = display_number;
3175 return (0);
8efc0c15 3176}
3177
396c147e 3178static int
b5a1596f 3179connect_local_xsocket_path(const char *pathname)
8efc0c15 3180{
5260325f 3181 int sock;
3182 struct sockaddr_un addr;
5260325f 3183
805e659f 3184 sock = socket(AF_UNIX, SOCK_STREAM, 0);
3185 if (sock < 0)
3186 error("socket: %.100s", strerror(errno));
3187 memset(&addr, 0, sizeof(addr));
3188 addr.sun_family = AF_UNIX;
b5a1596f 3189 strlcpy(addr.sun_path, pathname, sizeof addr.sun_path);
32596c7b 3190 if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
805e659f 3191 return sock;
3192 close(sock);
5260325f 3193 error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
3194 return -1;
8efc0c15 3195}
3196
b5a1596f 3197static int
3198connect_local_xsocket(u_int dnr)
3199{
3200 char buf[1024];
3201 snprintf(buf, sizeof buf, _PATH_UNIX_X, dnr);
3202 return connect_local_xsocket_path(buf);
3203}
3204
0b242b12 3205int
3206x11_connect_display(void)
8efc0c15 3207{
4f16046f 3208 u_int display_number;
5260325f 3209 const char *display;
0b242b12 3210 char buf[1024], *cp;
48e671d5 3211 struct addrinfo hints, *ai, *aitop;
3212 char strport[NI_MAXSERV];
4f16046f 3213 int gaierr, sock = 0;
5260325f 3214
5260325f 3215 /* Try to open a socket for the local X server. */
3216 display = getenv("DISPLAY");
3217 if (!display) {
3218 error("DISPLAY not set.");
0b242b12 3219 return -1;
5260325f 3220 }
aa3378df 3221 /*
3222 * Now we decode the value of the DISPLAY variable and make a
3223 * connection to the real X server.
3224 */
3225
b5a1596f 3226 /* Check if the display is from launchd. */
3227#ifdef __APPLE__
3228 if (strncmp(display, "/tmp/launch", 11) == 0) {
3229 sock = connect_local_xsocket_path(display);
3230 if (sock < 0)
3231 return -1;
3232
3233 /* OK, we now have a connection to the display. */
3234 return sock;
3235 }
3236#endif
aa3378df 3237 /*
3238 * Check if it is a unix domain socket. Unix domain displays are in
3239 * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
3240 */
5260325f 3241 if (strncmp(display, "unix:", 5) == 0 ||
3242 display[0] == ':') {
3243 /* Connect to the unix domain socket. */
4f16046f 3244 if (sscanf(strrchr(display, ':') + 1, "%u", &display_number) != 1) {
5260325f 3245 error("Could not parse display number from DISPLAY: %.100s",
184eed6a 3246 display);
0b242b12 3247 return -1;
5260325f 3248 }
3249 /* Create a socket. */
3250 sock = connect_local_xsocket(display_number);
3251 if (sock < 0)
0b242b12 3252 return -1;
5260325f 3253
3254 /* OK, we now have a connection to the display. */
0b242b12 3255 return sock;
5260325f 3256 }
aa3378df 3257 /*
3258 * Connect to an inet socket. The DISPLAY value is supposedly
3259 * hostname:d[.s], where hostname may also be numeric IP address.
3260 */
74860245 3261 strlcpy(buf, display, sizeof(buf));
5260325f 3262 cp = strchr(buf, ':');
3263 if (!cp) {
3264 error("Could not find ':' in DISPLAY: %.100s", display);
0b242b12 3265 return -1;
5260325f 3266 }
3267 *cp = 0;
aa3378df 3268 /* buf now contains the host name. But first we parse the display number. */
4f16046f 3269 if (sscanf(cp + 1, "%u", &display_number) != 1) {
5260325f 3270 error("Could not parse display number from DISPLAY: %.100s",
184eed6a 3271 display);
0b242b12 3272 return -1;
5260325f 3273 }
5260325f 3274
48e671d5 3275 /* Look up the host address */
3276 memset(&hints, 0, sizeof(hints));
3277 hints.ai_family = IPv4or6;
3278 hints.ai_socktype = SOCK_STREAM;
4f16046f 3279 snprintf(strport, sizeof strport, "%u", 6000 + display_number);
48e671d5 3280 if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
bb4626fe 3281 error("%.100s: unknown host. (%s)", buf,
3282 ssh_gai_strerror(gaierr));
0b242b12 3283 return -1;
8efc0c15 3284 }
48e671d5 3285 for (ai = aitop; ai; ai = ai->ai_next) {
3286 /* Create a socket. */
fe7dba42 3287 sock = socket_rdomain(ai->ai_family, ai->ai_socktype,
3288 ai->ai_protocol, channel_rdomain);
48e671d5 3289 if (sock < 0) {
d7ac5f18 3290 debug2("socket: %.100s", strerror(errno));
7368a6c8 3291 continue;
3292 }
3293 /* Connect it to the display. */
3294 if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
4f16046f 3295 debug2("connect %.100s port %u: %.100s", buf,
7368a6c8 3296 6000 + display_number, strerror(errno));
3297 close(sock);
3298 continue;
3299 }
3300 /* Success */
3301 break;
48e671d5 3302 }
48e671d5 3303 freeaddrinfo(aitop);
3304 if (!ai) {
4f16046f 3305 error("connect %.100s port %u: %.100s", buf, 6000 + display_number,
48e671d5 3306 strerror(errno));
0b242b12 3307 return -1;
8efc0c15 3308 }
bcc0381e 3309 set_nodelay(sock);
0b242b12 3310 return sock;
3311}
5260325f 3312
0b242b12 3313/*
3314 * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
3315 * the remote channel number. We should do whatever we want, and respond
3316 * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
3317 */
5260325f 3318
ebb90778 3319/* ARGSUSED */
0b242b12 3320void
7819b5c3 3321x11_input_open(int type, u_int32_t seq, void *ctxt)
0b242b12 3322{
719fc62f 3323 Channel *c = NULL;
3324 int remote_id, sock = 0;
0b242b12 3325 char *remote_host;
5260325f 3326
719fc62f 3327 debug("Received X11 open request.");
5260325f 3328
719fc62f 3329 remote_id = packet_get_int();
8e7895b8 3330
3331 if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
719fc62f 3332 remote_host = packet_get_string(NULL);
0b242b12 3333 } else {
3334 remote_host = xstrdup("unknown (remote did not supply name)");
0b242b12 3335 }
95500969 3336 packet_check_eom();
0b242b12 3337
3338 /* Obtain a connection to the real X display. */
3339 sock = x11_connect_display();
719fc62f 3340 if (sock != -1) {
3341 /* Allocate a channel for this connection. */
3342 c = channel_new("connected x11 socket",
3343 SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
3344 remote_host, 1);
3a0d3d54 3345 c->remote_id = remote_id;
3346 c->force_drain = 1;
719fc62f 3347 }
0d942eff 3348 xfree(remote_host);
719fc62f 3349 if (c == NULL) {
0b242b12 3350 /* Send refusal to the remote host. */
3351 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
719fc62f 3352 packet_put_int(remote_id);
0b242b12 3353 } else {
0b242b12 3354 /* Send a confirmation to the remote host. */
3355 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
719fc62f 3356 packet_put_int(remote_id);
3357 packet_put_int(c->self);
0b242b12 3358 }
719fc62f 3359 packet_send();
8efc0c15 3360}
3361
a22aff1f 3362/* dummy protocol handler that denies SSH-1 requests (agent/x11) */
ebb90778 3363/* ARGSUSED */
a22aff1f 3364void
7819b5c3 3365deny_input_open(int type, u_int32_t seq, void *ctxt)
a22aff1f 3366{
3367 int rchan = packet_get_int();
e1feb9bf 3368
6aacefa7 3369 switch (type) {
a22aff1f 3370 case SSH_SMSG_AGENT_OPEN:
3371 error("Warning: ssh server tried agent forwarding.");
3372 break;
3373 case SSH_SMSG_X11_OPEN:
3374 error("Warning: ssh server tried X11 forwarding.");
3375 break;
3376 default:
7819b5c3 3377 error("deny_input_open: type %d", type);
a22aff1f 3378 break;
3379 }
1908529f 3380 error("Warning: this is probably a break-in attempt by a malicious server.");
a22aff1f 3381 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
3382 packet_put_int(rchan);
3383 packet_send();
3384}
3385
aa3378df 3386/*
3387 * Requests forwarding of X11 connections, generates fake authentication
3388 * data, and enables authentication spoofing.
8e7895b8 3389 * This should be called in the client only.
aa3378df 3390 */
6ae2364d 3391void
9bf083eb 3392x11_request_forwarding_with_spoofing(int client_session_id, const char *disp,
0b242b12 3393 const char *proto, const char *data)
8efc0c15 3394{
1e3b8b07 3395 u_int data_len = (u_int) strlen(data) / 2;
ef07103c 3396 u_int i, value;
5260325f 3397 char *new_data;
3398 int screen_number;
3399 const char *cp;
ca75d7de 3400 u_int32_t rnd = 0;
5260325f 3401
4297b666 3402 if (x11_saved_display == NULL)
3403 x11_saved_display = xstrdup(disp);
3404 else if (strcmp(disp, x11_saved_display) != 0) {
ef07103c 3405 error("x11_request_forwarding_with_spoofing: different "
3406 "$DISPLAY already forwarded");
3407 return;
3408 }
3409
0875ae22 3410 cp = strchr(disp, ':');
5260325f 3411 if (cp)
3412 cp = strchr(cp, '.');
3413 if (cp)
d6d4897e 3414 screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
5260325f 3415 else
3416 screen_number = 0;
3417
ef07103c 3418 if (x11_saved_proto == NULL) {
3419 /* Save protocol name. */
3420 x11_saved_proto = xstrdup(proto);
3421 /*
56964485 3422 * Extract real authentication data and generate fake data
ef07103c 3423 * of the same length.
3424 */
3425 x11_saved_data = xmalloc(data_len);
3426 x11_fake_data = xmalloc(data_len);
3427 for (i = 0; i < data_len; i++) {
3428 if (sscanf(data + 2 * i, "%2x", &value) != 1)
3429 fatal("x11_request_forwarding: bad "
3430 "authentication data: %.100s", data);
3431 if (i % 4 == 0)
3432 rnd = arc4random();
3433 x11_saved_data[i] = value;
3434 x11_fake_data[i] = rnd & 0xff;
3435 rnd >>= 8;
3436 }
3437 x11_saved_data_len = data_len;
3438 x11_fake_data_len = data_len;
3439 }
5260325f 3440
3441 /* Convert the fake data into hex. */
ef07103c 3442 new_data = tohex(x11_fake_data, data_len);
5260325f 3443
3444 /* Send the request packet. */
0b242b12 3445 if (compat20) {
3446 channel_request_start(client_session_id, "x11-req", 0);
3447 packet_put_char(0); /* XXX bool single connection */
3448 } else {
3449 packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
3450 }
3451 packet_put_cstring(proto);
3452 packet_put_cstring(new_data);
5260325f 3453 packet_put_int(screen_number);
3454 packet_send();
3455 packet_write_wait();
3456 xfree(new_data);
8efc0c15 3457}
3458
8e7895b8 3459
3460/* -- agent forwarding */
3461
8efc0c15 3462/* Sends a message to the server to request authentication fd forwarding. */
3463
6ae2364d 3464void
d5bb9418 3465auth_request_forwarding(void)
8efc0c15 3466{
5260325f 3467 packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
3468 packet_send();
3469 packet_write_wait();
8efc0c15 3470}
git-cvsimport mirror of OpenSSH
This page took 0.960267 seconds and 5 git commands to generate.