blob: 2721ec6bc466205c036719a324331f65d16c80f4 [file] [log] [blame]
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001/*
Damien Miller95def091999-11-25 00:26:21 +11002 * Author: Tatu Ylonen <ylo@cs.hut.fi>
Damien Miller95def091999-11-25 00:26:21 +11003 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
4 * All rights reserved
Damien Miller95def091999-11-25 00:26:21 +11005 * This file contains functions for generic socket connection forwarding.
6 * There is also code for initiating connection forwarding for X11 connections,
7 * arbitrary tcp/ip connections, and the authentication agent connection.
Damien Miller4af51302000-04-16 11:18:38 +10008 *
Damien Millere4340be2000-09-16 13:29:08 +11009 * As far as I am concerned, the code I have written for this software
10 * can be used freely for any purpose. Any derived versions of this
11 * software must be clearly marked as such, and if the derived work is
12 * incompatible with the protocol description in the RFC file, it must be
13 * called by a name other than "ssh" or "Secure Shell".
14 *
Damien Miller33b13562000-04-04 14:38:59 +100015 * SSH2 support added by Markus Friedl.
Ben Lindstrom44697232001-07-04 03:32:30 +000016 * Copyright (c) 1999, 2000, 2001 Markus Friedl. All rights reserved.
Damien Millere4340be2000-09-16 13:29:08 +110017 * Copyright (c) 1999 Dug Song. All rights reserved.
18 * Copyright (c) 1999 Theo de Raadt. All rights reserved.
19 *
20 * Redistribution and use in source and binary forms, with or without
21 * modification, are permitted provided that the following conditions
22 * are met:
23 * 1. Redistributions of source code must retain the above copyright
24 * notice, this list of conditions and the following disclaimer.
25 * 2. Redistributions in binary form must reproduce the above copyright
26 * notice, this list of conditions and the following disclaimer in the
27 * documentation and/or other materials provided with the distribution.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
30 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
31 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
32 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
33 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
34 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
38 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
Damien Miller95def091999-11-25 00:26:21 +110039 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +100040
41#include "includes.h"
Ben Lindstrom44697232001-07-04 03:32:30 +000042RCSID("$OpenBSD: channels.c,v 1.128 2001/06/25 08:25:35 markus Exp $");
Damien Millerd4a8b7e1999-10-27 13:42:43 +100043
44#include "ssh.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000045#include "ssh1.h"
46#include "ssh2.h"
Damien Millerd4a8b7e1999-10-27 13:42:43 +100047#include "packet.h"
48#include "xmalloc.h"
Damien Millerd4a8b7e1999-10-27 13:42:43 +100049#include "uidswap.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000050#include "log.h"
51#include "misc.h"
Damien Millerd4a8b7e1999-10-27 13:42:43 +100052#include "channels.h"
Damien Millerd4a8b7e1999-10-27 13:42:43 +100053#include "compat.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000054#include "canohost.h"
Damien Miller994cf142000-07-21 10:19:44 +100055#include "key.h"
56#include "authfd.h"
57
Damien Millerd4a8b7e1999-10-27 13:42:43 +100058
Ben Lindstrome9c99912001-06-09 00:41:05 +000059/* -- channel core */
Damien Millerd4a8b7e1999-10-27 13:42:43 +100060
Damien Miller5428f641999-11-25 11:54:57 +110061/*
62 * Pointer to an array containing all allocated channels. The array is
63 * dynamically extended as needed.
64 */
Ben Lindstrom99c73b32001-05-05 04:09:47 +000065static Channel **channels = NULL;
Damien Millerd4a8b7e1999-10-27 13:42:43 +100066
Damien Miller5428f641999-11-25 11:54:57 +110067/*
68 * Size of the channel array. All slots of the array must always be
Ben Lindstrom99c73b32001-05-05 04:09:47 +000069 * initialized (at least the type field); unused slots set to NULL
Damien Miller5428f641999-11-25 11:54:57 +110070 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +100071static int channels_alloc = 0;
72
Damien Miller5428f641999-11-25 11:54:57 +110073/*
74 * Maximum file descriptor value used in any of the channels. This is
Ben Lindstrom99c73b32001-05-05 04:09:47 +000075 * updated in channel_new.
Damien Miller5428f641999-11-25 11:54:57 +110076 */
Damien Miller5e953212001-01-30 09:14:00 +110077static int channel_max_fd = 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +100078
Damien Millerd4a8b7e1999-10-27 13:42:43 +100079
Ben Lindstrome9c99912001-06-09 00:41:05 +000080/* -- tcp forwarding */
Damien Millerd4a8b7e1999-10-27 13:42:43 +100081
Damien Miller5428f641999-11-25 11:54:57 +110082/*
83 * Data structure for storing which hosts are permitted for forward requests.
84 * The local sides of any remote forwards are stored in this array to prevent
85 * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
86 * network (which might be behind a firewall).
87 */
Damien Miller95def091999-11-25 00:26:21 +110088typedef struct {
Damien Millerb38eff82000-04-01 11:09:21 +100089 char *host_to_connect; /* Connect to 'host'. */
90 u_short port_to_connect; /* Connect to 'port'. */
91 u_short listen_port; /* Remote side should listen port number. */
Damien Millerd4a8b7e1999-10-27 13:42:43 +100092} ForwardPermission;
93
94/* List of all permitted host/port pairs to connect. */
95static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
Ben Lindstrome9c99912001-06-09 00:41:05 +000096
Damien Millerd4a8b7e1999-10-27 13:42:43 +100097/* Number of permitted host/port pairs in the array. */
98static int num_permitted_opens = 0;
Damien Miller5428f641999-11-25 11:54:57 +110099/*
100 * If this is true, all opens are permitted. This is the case on the server
101 * on which we have to trust the client anyway, and the user could do
102 * anything after logging in anyway.
103 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000104static int all_opens_permitted = 0;
105
Ben Lindstrome9c99912001-06-09 00:41:05 +0000106
107/* -- X11 forwarding */
108
109/* Maximum number of fake X11 displays to try. */
110#define MAX_DISPLAYS 1000
111
112/* Saved X11 authentication protocol name. */
113static char *x11_saved_proto = NULL;
114
115/* Saved X11 authentication data. This is the real data. */
116static char *x11_saved_data = NULL;
117static u_int x11_saved_data_len = 0;
118
119/*
120 * Fake X11 authentication data. This is what the server will be sending us;
121 * we should replace any occurrences of this by the real data.
122 */
123static char *x11_fake_data = NULL;
124static u_int x11_fake_data_len;
125
126
127/* -- agent forwarding */
128
129#define NUM_SOCKS 10
130
131/* Name and directory of socket for authentication agent forwarding. */
132static char *auth_sock_name = NULL;
133static char *auth_sock_dir = NULL;
134
Ben Lindstrom226cfa02001-01-22 05:34:40 +0000135/* AF_UNSPEC or AF_INET or AF_INET6 */
136extern int IPv4or6;
137
Ben Lindstrome9c99912001-06-09 00:41:05 +0000138/* helper */
Ben Lindstrombba81212001-06-25 05:01:22 +0000139static void port_open_helper(Channel *c, char *rtype);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000140
Ben Lindstrome9c99912001-06-09 00:41:05 +0000141/* -- channel core */
Damien Millerb38eff82000-04-01 11:09:21 +1000142
143Channel *
144channel_lookup(int id)
145{
146 Channel *c;
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000147
Damien Millerc0fd17f2000-06-26 10:22:53 +1000148 if (id < 0 || id > channels_alloc) {
Damien Millerb38eff82000-04-01 11:09:21 +1000149 log("channel_lookup: %d: bad id", id);
150 return NULL;
151 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000152 c = channels[id];
153 if (c == NULL) {
Damien Millerb38eff82000-04-01 11:09:21 +1000154 log("channel_lookup: %d: bad id: channel free", id);
155 return NULL;
156 }
157 return c;
158}
159
Damien Miller5428f641999-11-25 11:54:57 +1100160/*
Damien Millere247cc42000-05-07 12:03:14 +1000161 * Register filedescriptors for a channel, used when allocating a channel or
Damien Miller6f83b8e2000-05-02 09:23:45 +1000162 * when the channel consumer/producer is ready, e.g. shell exec'd
Damien Miller5428f641999-11-25 11:54:57 +1100163 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000164
Ben Lindstrombba81212001-06-25 05:01:22 +0000165static void
Damien Miller69b69aa2000-10-28 14:19:58 +1100166channel_register_fds(Channel *c, int rfd, int wfd, int efd,
167 int extusage, int nonblock)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000168{
Damien Miller95def091999-11-25 00:26:21 +1100169 /* Update the maximum file descriptor value. */
Damien Miller5e953212001-01-30 09:14:00 +1100170 channel_max_fd = MAX(channel_max_fd, rfd);
171 channel_max_fd = MAX(channel_max_fd, wfd);
172 channel_max_fd = MAX(channel_max_fd, efd);
173
Damien Miller5428f641999-11-25 11:54:57 +1100174 /* XXX set close-on-exec -markus */
Damien Millere247cc42000-05-07 12:03:14 +1000175
Damien Miller6f83b8e2000-05-02 09:23:45 +1000176 c->rfd = rfd;
177 c->wfd = wfd;
178 c->sock = (rfd == wfd) ? rfd : -1;
179 c->efd = efd;
180 c->extended_usage = extusage;
Damien Miller69b69aa2000-10-28 14:19:58 +1100181
Damien Miller79438cc2001-02-16 12:34:57 +1100182 /* XXX ugly hack: nonblock is only set by the server */
183 if (nonblock && isatty(c->rfd)) {
Ben Lindstromcc74df72001-03-05 06:20:14 +0000184 debug("channel %d: rfd %d isatty", c->self, c->rfd);
Damien Miller79438cc2001-02-16 12:34:57 +1100185 c->isatty = 1;
186 if (!isatty(c->wfd)) {
Ben Lindstromcc74df72001-03-05 06:20:14 +0000187 error("channel %d: wfd %d is not a tty?",
Damien Miller79438cc2001-02-16 12:34:57 +1100188 c->self, c->wfd);
189 }
190 } else {
191 c->isatty = 0;
192 }
193
Damien Miller69b69aa2000-10-28 14:19:58 +1100194 /* enable nonblocking mode */
195 if (nonblock) {
196 if (rfd != -1)
197 set_nonblock(rfd);
198 if (wfd != -1)
199 set_nonblock(wfd);
200 if (efd != -1)
201 set_nonblock(efd);
202 }
Damien Miller6f83b8e2000-05-02 09:23:45 +1000203}
204
205/*
206 * Allocate a new channel object and set its type and socket. This will cause
207 * remote_name to be freed.
208 */
209
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000210Channel *
Damien Miller6f83b8e2000-05-02 09:23:45 +1000211channel_new(char *ctype, int type, int rfd, int wfd, int efd,
Damien Miller69b69aa2000-10-28 14:19:58 +1100212 int window, int maxpack, int extusage, char *remote_name, int nonblock)
Damien Miller6f83b8e2000-05-02 09:23:45 +1000213{
214 int i, found;
215 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000216
Damien Miller95def091999-11-25 00:26:21 +1100217 /* Do initial allocation if this is the first call. */
218 if (channels_alloc == 0) {
Damien Miller33b13562000-04-04 14:38:59 +1000219 chan_init();
Damien Miller95def091999-11-25 00:26:21 +1100220 channels_alloc = 10;
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000221 channels = xmalloc(channels_alloc * sizeof(Channel *));
Damien Miller95def091999-11-25 00:26:21 +1100222 for (i = 0; i < channels_alloc; i++)
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000223 channels[i] = NULL;
Ben Lindstrom601e4362001-06-21 03:19:23 +0000224 fatal_add_cleanup((void (*) (void *)) channel_free_all, NULL);
Damien Miller95def091999-11-25 00:26:21 +1100225 }
226 /* Try to find a free slot where to put the new channel. */
227 for (found = -1, i = 0; i < channels_alloc; i++)
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000228 if (channels[i] == NULL) {
Damien Miller95def091999-11-25 00:26:21 +1100229 /* Found a free slot. */
230 found = i;
231 break;
232 }
233 if (found == -1) {
Damien Miller5428f641999-11-25 11:54:57 +1100234 /* There are no free slots. Take last+1 slot and expand the array. */
Damien Miller95def091999-11-25 00:26:21 +1100235 found = channels_alloc;
236 channels_alloc += 10;
Damien Millerd3444942000-09-30 14:20:03 +1100237 debug2("channel: expanding %d", channels_alloc);
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000238 channels = xrealloc(channels, channels_alloc * sizeof(Channel *));
Damien Miller95def091999-11-25 00:26:21 +1100239 for (i = found; i < channels_alloc; i++)
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000240 channels[i] = NULL;
Damien Miller95def091999-11-25 00:26:21 +1100241 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000242 /* Initialize and return new channel. */
243 c = channels[found] = xmalloc(sizeof(Channel));
Damien Miller95def091999-11-25 00:26:21 +1100244 buffer_init(&c->input);
245 buffer_init(&c->output);
Damien Millerb38eff82000-04-01 11:09:21 +1000246 buffer_init(&c->extended);
Damien Miller95def091999-11-25 00:26:21 +1100247 chan_init_iostates(c);
Damien Miller69b69aa2000-10-28 14:19:58 +1100248 channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
Damien Miller95def091999-11-25 00:26:21 +1100249 c->self = found;
250 c->type = type;
Damien Millerb38eff82000-04-01 11:09:21 +1000251 c->ctype = ctype;
Damien Millerbd483e72000-04-30 10:00:53 +1000252 c->local_window = window;
253 c->local_window_max = window;
254 c->local_consumed = 0;
255 c->local_maxpacket = maxpack;
Damien Miller95def091999-11-25 00:26:21 +1100256 c->remote_id = -1;
257 c->remote_name = remote_name;
Damien Millerb38eff82000-04-01 11:09:21 +1000258 c->remote_window = 0;
259 c->remote_maxpacket = 0;
260 c->cb_fn = NULL;
261 c->cb_arg = NULL;
262 c->cb_event = 0;
263 c->dettach_user = NULL;
Damien Millerad833b32000-08-23 10:46:23 +1000264 c->input_filter = NULL;
Damien Miller95def091999-11-25 00:26:21 +1100265 debug("channel %d: new [%s]", found, remote_name);
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000266 return c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000267}
Damien Miller6f83b8e2000-05-02 09:23:45 +1000268
269/* Close all channel fd/socket. */
270
Ben Lindstrombba81212001-06-25 05:01:22 +0000271static void
Damien Miller6f83b8e2000-05-02 09:23:45 +1000272channel_close_fds(Channel *c)
273{
Ben Lindstromc0dee1a2001-06-05 20:52:50 +0000274 debug3("channel_close_fds: channel %d: r %d w %d e %d",
275 c->self, c->rfd, c->wfd, c->efd);
276
Damien Miller6f83b8e2000-05-02 09:23:45 +1000277 if (c->sock != -1) {
278 close(c->sock);
279 c->sock = -1;
280 }
281 if (c->rfd != -1) {
282 close(c->rfd);
283 c->rfd = -1;
284 }
285 if (c->wfd != -1) {
286 close(c->wfd);
287 c->wfd = -1;
288 }
289 if (c->efd != -1) {
290 close(c->efd);
291 c->efd = -1;
292 }
293}
294
295/* Free the channel and close its fd/socket. */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000296
Damien Miller4af51302000-04-16 11:18:38 +1000297void
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000298channel_free(Channel *c)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000299{
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000300 char *s;
Ben Lindstromc0dee1a2001-06-05 20:52:50 +0000301 int i, n;
302
303 for (n = 0, i = 0; i < channels_alloc; i++)
304 if (channels[i])
305 n++;
Ben Lindstrom4c247552001-06-05 20:56:47 +0000306 debug("channel_free: channel %d: %s, nchannels %d", c->self,
Ben Lindstromc0dee1a2001-06-05 20:52:50 +0000307 c->remote_name ? c->remote_name : "???", n);
Ben Lindstrom6c3ae2b2000-12-30 03:25:14 +0000308
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000309 s = channel_open_message();
Ben Lindstrom4c247552001-06-05 20:56:47 +0000310 debug3("channel_free: status: %s", s);
Ben Lindstrom6c3ae2b2000-12-30 03:25:14 +0000311 xfree(s);
312
Damien Miller33b13562000-04-04 14:38:59 +1000313 if (c->dettach_user != NULL) {
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000314 debug("channel_free: channel %d: dettaching channel user", c->self);
Damien Miller33b13562000-04-04 14:38:59 +1000315 c->dettach_user(c->self, NULL);
316 }
Damien Miller6f83b8e2000-05-02 09:23:45 +1000317 if (c->sock != -1)
Damien Millerb38eff82000-04-01 11:09:21 +1000318 shutdown(c->sock, SHUT_RDWR);
Damien Miller6f83b8e2000-05-02 09:23:45 +1000319 channel_close_fds(c);
Damien Millerb38eff82000-04-01 11:09:21 +1000320 buffer_free(&c->input);
321 buffer_free(&c->output);
322 buffer_free(&c->extended);
Damien Millerb38eff82000-04-01 11:09:21 +1000323 if (c->remote_name) {
324 xfree(c->remote_name);
325 c->remote_name = NULL;
Damien Miller95def091999-11-25 00:26:21 +1100326 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000327 channels[c->self] = NULL;
328 xfree(c);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000329}
330
Ben Lindstrome9c99912001-06-09 00:41:05 +0000331void
Ben Lindstrom601e4362001-06-21 03:19:23 +0000332channel_free_all(void)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000333{
334 int i;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000335
Ben Lindstrom601e4362001-06-21 03:19:23 +0000336 for (i = 0; i < channels_alloc; i++)
337 if (channels[i] != NULL)
338 channel_free(channels[i]);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000339}
340
341/*
342 * Closes the sockets/fds of all channels. This is used to close extra file
343 * descriptors after a fork.
344 */
345
346void
347channel_close_all()
348{
349 int i;
350
351 for (i = 0; i < channels_alloc; i++)
352 if (channels[i] != NULL)
353 channel_close_fds(channels[i]);
354}
355
356/*
357 * Returns true if no channel has too much buffered data, and false if one or
358 * more channel is overfull.
359 */
360
361int
362channel_not_very_much_buffered_data()
363{
364 u_int i;
365 Channel *c;
366
367 for (i = 0; i < channels_alloc; i++) {
368 c = channels[i];
369 if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
370 if (!compat20 && buffer_len(&c->input) > packet_get_maxsize()) {
371 debug("channel %d: big input buffer %d",
372 c->self, buffer_len(&c->input));
373 return 0;
374 }
375 if (buffer_len(&c->output) > packet_get_maxsize()) {
376 debug("channel %d: big output buffer %d",
377 c->self, buffer_len(&c->output));
378 return 0;
379 }
380 }
381 }
382 return 1;
383}
384
385/* Returns true if any channel is still open. */
386
387int
388channel_still_open()
389{
390 int i;
391 Channel *c;
392
393 for (i = 0; i < channels_alloc; i++) {
394 c = channels[i];
395 if (c == NULL)
396 continue;
397 switch (c->type) {
398 case SSH_CHANNEL_X11_LISTENER:
399 case SSH_CHANNEL_PORT_LISTENER:
400 case SSH_CHANNEL_RPORT_LISTENER:
401 case SSH_CHANNEL_CLOSED:
402 case SSH_CHANNEL_AUTH_SOCKET:
403 case SSH_CHANNEL_DYNAMIC:
404 case SSH_CHANNEL_CONNECTING:
405 case SSH_CHANNEL_ZOMBIE:
406 continue;
407 case SSH_CHANNEL_LARVAL:
408 if (!compat20)
409 fatal("cannot happen: SSH_CHANNEL_LARVAL");
410 continue;
411 case SSH_CHANNEL_OPENING:
412 case SSH_CHANNEL_OPEN:
413 case SSH_CHANNEL_X11_OPEN:
414 return 1;
415 case SSH_CHANNEL_INPUT_DRAINING:
416 case SSH_CHANNEL_OUTPUT_DRAINING:
417 if (!compat13)
418 fatal("cannot happen: OUT_DRAIN");
419 return 1;
420 default:
421 fatal("channel_still_open: bad channel type %d", c->type);
422 /* NOTREACHED */
423 }
424 }
425 return 0;
426}
427
428/* Returns the id of an open channel suitable for keepaliving */
429
430int
431channel_find_open()
432{
433 int i;
434 Channel *c;
435
436 for (i = 0; i < channels_alloc; i++) {
437 c = channels[i];
438 if (c == NULL)
439 continue;
440 switch (c->type) {
441 case SSH_CHANNEL_CLOSED:
442 case SSH_CHANNEL_DYNAMIC:
443 case SSH_CHANNEL_X11_LISTENER:
444 case SSH_CHANNEL_PORT_LISTENER:
445 case SSH_CHANNEL_RPORT_LISTENER:
446 case SSH_CHANNEL_OPENING:
447 case SSH_CHANNEL_CONNECTING:
448 case SSH_CHANNEL_ZOMBIE:
449 continue;
450 case SSH_CHANNEL_LARVAL:
451 case SSH_CHANNEL_AUTH_SOCKET:
452 case SSH_CHANNEL_OPEN:
453 case SSH_CHANNEL_X11_OPEN:
454 return i;
455 case SSH_CHANNEL_INPUT_DRAINING:
456 case SSH_CHANNEL_OUTPUT_DRAINING:
457 if (!compat13)
458 fatal("cannot happen: OUT_DRAIN");
459 return i;
460 default:
461 fatal("channel_find_open: bad channel type %d", c->type);
462 /* NOTREACHED */
463 }
464 }
465 return -1;
466}
467
468
469/*
470 * Returns a message describing the currently open forwarded connections,
471 * suitable for sending to the client. The message contains crlf pairs for
472 * newlines.
473 */
474
475char *
476channel_open_message()
477{
478 Buffer buffer;
479 Channel *c;
480 char buf[1024], *cp;
481 int i;
482
483 buffer_init(&buffer);
484 snprintf(buf, sizeof buf, "The following connections are open:\r\n");
485 buffer_append(&buffer, buf, strlen(buf));
486 for (i = 0; i < channels_alloc; i++) {
487 c = channels[i];
488 if (c == NULL)
489 continue;
490 switch (c->type) {
491 case SSH_CHANNEL_X11_LISTENER:
492 case SSH_CHANNEL_PORT_LISTENER:
493 case SSH_CHANNEL_RPORT_LISTENER:
494 case SSH_CHANNEL_CLOSED:
495 case SSH_CHANNEL_AUTH_SOCKET:
496 case SSH_CHANNEL_ZOMBIE:
497 continue;
498 case SSH_CHANNEL_LARVAL:
499 case SSH_CHANNEL_OPENING:
500 case SSH_CHANNEL_CONNECTING:
501 case SSH_CHANNEL_DYNAMIC:
502 case SSH_CHANNEL_OPEN:
503 case SSH_CHANNEL_X11_OPEN:
504 case SSH_CHANNEL_INPUT_DRAINING:
505 case SSH_CHANNEL_OUTPUT_DRAINING:
506 snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n",
507 c->self, c->remote_name,
508 c->type, c->remote_id,
509 c->istate, buffer_len(&c->input),
510 c->ostate, buffer_len(&c->output),
511 c->rfd, c->wfd);
512 buffer_append(&buffer, buf, strlen(buf));
513 continue;
514 default:
515 fatal("channel_open_message: bad channel type %d", c->type);
516 /* NOTREACHED */
517 }
518 }
519 buffer_append(&buffer, "\0", 1);
520 cp = xstrdup(buffer_ptr(&buffer));
521 buffer_free(&buffer);
522 return cp;
523}
524
525void
526channel_send_open(int id)
527{
528 Channel *c = channel_lookup(id);
529 if (c == NULL) {
530 log("channel_send_open: %d: bad id", id);
531 return;
532 }
533 debug("send channel open %d", id);
534 packet_start(SSH2_MSG_CHANNEL_OPEN);
535 packet_put_cstring(c->ctype);
536 packet_put_int(c->self);
537 packet_put_int(c->local_window);
538 packet_put_int(c->local_maxpacket);
539 packet_send();
540}
541
542void
543channel_request(int id, char *service, int wantconfirm)
544{
545 channel_request_start(id, service, wantconfirm);
546 packet_send();
547 debug("channel request %d: %s", id, service) ;
548}
549void
550channel_request_start(int id, char *service, int wantconfirm)
551{
552 Channel *c = channel_lookup(id);
553 if (c == NULL) {
554 log("channel_request: %d: bad id", id);
555 return;
556 }
557 packet_start(SSH2_MSG_CHANNEL_REQUEST);
558 packet_put_int(c->remote_id);
559 packet_put_cstring(service);
560 packet_put_char(wantconfirm);
561}
562void
563channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg)
564{
565 Channel *c = channel_lookup(id);
566 if (c == NULL) {
567 log("channel_register_callback: %d: bad id", id);
568 return;
569 }
570 c->cb_event = mtype;
571 c->cb_fn = fn;
572 c->cb_arg = arg;
573}
574void
575channel_register_cleanup(int id, channel_callback_fn *fn)
576{
577 Channel *c = channel_lookup(id);
578 if (c == NULL) {
579 log("channel_register_cleanup: %d: bad id", id);
580 return;
581 }
582 c->dettach_user = fn;
583}
584void
585channel_cancel_cleanup(int id)
586{
587 Channel *c = channel_lookup(id);
588 if (c == NULL) {
589 log("channel_cancel_cleanup: %d: bad id", id);
590 return;
591 }
592 c->dettach_user = NULL;
593}
594void
595channel_register_filter(int id, channel_filter_fn *fn)
596{
597 Channel *c = channel_lookup(id);
598 if (c == NULL) {
599 log("channel_register_filter: %d: bad id", id);
600 return;
601 }
602 c->input_filter = fn;
603}
604
605void
606channel_set_fds(int id, int rfd, int wfd, int efd,
607 int extusage, int nonblock)
608{
609 Channel *c = channel_lookup(id);
610 if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
611 fatal("channel_activate for non-larval channel %d.", id);
612 channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
613 c->type = SSH_CHANNEL_OPEN;
614 /* XXX window size? */
615 c->local_window = c->local_window_max = c->local_maxpacket * 2;
616 packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
617 packet_put_int(c->remote_id);
618 packet_put_int(c->local_window);
619 packet_send();
620}
621
Damien Miller5428f641999-11-25 11:54:57 +1100622/*
Damien Millerb38eff82000-04-01 11:09:21 +1000623 * 'channel_pre*' are called just before select() to add any bits relevant to
624 * channels in the select bitmasks.
Damien Miller5428f641999-11-25 11:54:57 +1100625 */
Damien Millerb38eff82000-04-01 11:09:21 +1000626/*
627 * 'channel_post*': perform any appropriate operations for channels which
628 * have events pending.
629 */
630typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset);
631chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
632chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
633
Ben Lindstrombba81212001-06-25 05:01:22 +0000634static void
Damien Millerb38eff82000-04-01 11:09:21 +1000635channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset)
636{
637 FD_SET(c->sock, readset);
638}
639
Ben Lindstrombba81212001-06-25 05:01:22 +0000640static void
Ben Lindstrom7ad97102000-12-06 01:42:49 +0000641channel_pre_connecting(Channel *c, fd_set * readset, fd_set * writeset)
642{
643 debug3("channel %d: waiting for connection", c->self);
644 FD_SET(c->sock, writeset);
645}
646
Ben Lindstrombba81212001-06-25 05:01:22 +0000647static void
Damien Millerb38eff82000-04-01 11:09:21 +1000648channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset)
649{
650 if (buffer_len(&c->input) < packet_get_maxsize())
651 FD_SET(c->sock, readset);
652 if (buffer_len(&c->output) > 0)
653 FD_SET(c->sock, writeset);
654}
655
Ben Lindstrombba81212001-06-25 05:01:22 +0000656static void
Damien Millerb38eff82000-04-01 11:09:21 +1000657channel_pre_open_15(Channel *c, fd_set * readset, fd_set * writeset)
658{
659 /* test whether sockets are 'alive' for read/write */
660 if (c->istate == CHAN_INPUT_OPEN)
661 if (buffer_len(&c->input) < packet_get_maxsize())
662 FD_SET(c->sock, readset);
663 if (c->ostate == CHAN_OUTPUT_OPEN ||
664 c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
665 if (buffer_len(&c->output) > 0) {
666 FD_SET(c->sock, writeset);
667 } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
668 chan_obuf_empty(c);
669 }
670 }
671}
672
Ben Lindstrombba81212001-06-25 05:01:22 +0000673static void
Damien Miller33b13562000-04-04 14:38:59 +1000674channel_pre_open_20(Channel *c, fd_set * readset, fd_set * writeset)
675{
676 if (c->istate == CHAN_INPUT_OPEN &&
677 c->remote_window > 0 &&
678 buffer_len(&c->input) < c->remote_window)
679 FD_SET(c->rfd, readset);
680 if (c->ostate == CHAN_OUTPUT_OPEN ||
681 c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
682 if (buffer_len(&c->output) > 0) {
683 FD_SET(c->wfd, writeset);
684 } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
685 chan_obuf_empty(c);
686 }
687 }
688 /** XXX check close conditions, too */
689 if (c->efd != -1) {
690 if (c->extended_usage == CHAN_EXTENDED_WRITE &&
691 buffer_len(&c->extended) > 0)
692 FD_SET(c->efd, writeset);
693 else if (c->extended_usage == CHAN_EXTENDED_READ &&
694 buffer_len(&c->extended) < c->remote_window)
695 FD_SET(c->efd, readset);
696 }
697}
698
Ben Lindstrombba81212001-06-25 05:01:22 +0000699static void
Damien Millerb38eff82000-04-01 11:09:21 +1000700channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset)
701{
702 if (buffer_len(&c->input) == 0) {
703 packet_start(SSH_MSG_CHANNEL_CLOSE);
704 packet_put_int(c->remote_id);
705 packet_send();
706 c->type = SSH_CHANNEL_CLOSED;
Ben Lindstromc486d882001-04-11 16:08:34 +0000707 debug("channel %d: closing after input drain.", c->self);
Damien Millerb38eff82000-04-01 11:09:21 +1000708 }
709}
710
Ben Lindstrombba81212001-06-25 05:01:22 +0000711static void
Damien Millerb38eff82000-04-01 11:09:21 +1000712channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset)
713{
714 if (buffer_len(&c->output) == 0)
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000715 chan_mark_dead(c);
Damien Miller4af51302000-04-16 11:18:38 +1000716 else
Damien Millerb38eff82000-04-01 11:09:21 +1000717 FD_SET(c->sock, writeset);
718}
719
720/*
721 * This is a special state for X11 authentication spoofing. An opened X11
722 * connection (when authentication spoofing is being done) remains in this
723 * state until the first packet has been completely read. The authentication
724 * data in that packet is then substituted by the real data if it matches the
725 * fake data, and the channel is put into normal mode.
Damien Millerbd483e72000-04-30 10:00:53 +1000726 * XXX All this happens at the client side.
Ben Lindstrome9c99912001-06-09 00:41:05 +0000727 * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
Damien Millerb38eff82000-04-01 11:09:21 +1000728 */
Ben Lindstrombba81212001-06-25 05:01:22 +0000729static int
Ben Lindstrome9c99912001-06-09 00:41:05 +0000730x11_open_helper(Buffer *b)
Damien Millerb38eff82000-04-01 11:09:21 +1000731{
Ben Lindstrom46c16222000-12-22 01:43:59 +0000732 u_char *ucp;
733 u_int proto_len, data_len;
Damien Millerb38eff82000-04-01 11:09:21 +1000734
735 /* Check if the fixed size part of the packet is in buffer. */
Ben Lindstrome9c99912001-06-09 00:41:05 +0000736 if (buffer_len(b) < 12)
Damien Millerb38eff82000-04-01 11:09:21 +1000737 return 0;
738
739 /* Parse the lengths of variable-length fields. */
Ben Lindstrome9c99912001-06-09 00:41:05 +0000740 ucp = (u_char *) buffer_ptr(b);
Damien Millerb38eff82000-04-01 11:09:21 +1000741 if (ucp[0] == 0x42) { /* Byte order MSB first. */
742 proto_len = 256 * ucp[6] + ucp[7];
743 data_len = 256 * ucp[8] + ucp[9];
744 } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
745 proto_len = ucp[6] + 256 * ucp[7];
746 data_len = ucp[8] + 256 * ucp[9];
747 } else {
748 debug("Initial X11 packet contains bad byte order byte: 0x%x",
749 ucp[0]);
750 return -1;
751 }
752
753 /* Check if the whole packet is in buffer. */
Ben Lindstrome9c99912001-06-09 00:41:05 +0000754 if (buffer_len(b) <
Damien Millerb38eff82000-04-01 11:09:21 +1000755 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
756 return 0;
757
758 /* Check if authentication protocol matches. */
759 if (proto_len != strlen(x11_saved_proto) ||
760 memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
761 debug("X11 connection uses different authentication protocol.");
762 return -1;
763 }
764 /* Check if authentication data matches our fake data. */
765 if (data_len != x11_fake_data_len ||
766 memcmp(ucp + 12 + ((proto_len + 3) & ~3),
767 x11_fake_data, x11_fake_data_len) != 0) {
768 debug("X11 auth data does not match fake data.");
769 return -1;
770 }
771 /* Check fake data length */
772 if (x11_fake_data_len != x11_saved_data_len) {
773 error("X11 fake_data_len %d != saved_data_len %d",
774 x11_fake_data_len, x11_saved_data_len);
775 return -1;
776 }
777 /*
778 * Received authentication protocol and data match
779 * our fake data. Substitute the fake data with real
780 * data.
781 */
782 memcpy(ucp + 12 + ((proto_len + 3) & ~3),
783 x11_saved_data, x11_saved_data_len);
784 return 1;
785}
786
Ben Lindstrombba81212001-06-25 05:01:22 +0000787static void
Damien Millerb38eff82000-04-01 11:09:21 +1000788channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset)
789{
Ben Lindstrome9c99912001-06-09 00:41:05 +0000790 int ret = x11_open_helper(&c->output);
Damien Millerb38eff82000-04-01 11:09:21 +1000791 if (ret == 1) {
792 /* Start normal processing for the channel. */
793 c->type = SSH_CHANNEL_OPEN;
Damien Miller78928792000-04-12 20:17:38 +1000794 channel_pre_open_13(c, readset, writeset);
Damien Millerb38eff82000-04-01 11:09:21 +1000795 } else if (ret == -1) {
796 /*
797 * We have received an X11 connection that has bad
798 * authentication information.
799 */
Ben Lindstrom6df8ef42001-03-05 07:47:23 +0000800 log("X11 connection rejected because of wrong authentication.");
Damien Millerb38eff82000-04-01 11:09:21 +1000801 buffer_clear(&c->input);
802 buffer_clear(&c->output);
803 close(c->sock);
804 c->sock = -1;
805 c->type = SSH_CHANNEL_CLOSED;
806 packet_start(SSH_MSG_CHANNEL_CLOSE);
807 packet_put_int(c->remote_id);
808 packet_send();
809 }
810}
811
Ben Lindstrombba81212001-06-25 05:01:22 +0000812static void
Damien Millerbd483e72000-04-30 10:00:53 +1000813channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset)
Damien Millerb38eff82000-04-01 11:09:21 +1000814{
Ben Lindstrome9c99912001-06-09 00:41:05 +0000815 int ret = x11_open_helper(&c->output);
Damien Millerb38eff82000-04-01 11:09:21 +1000816 if (ret == 1) {
817 c->type = SSH_CHANNEL_OPEN;
Damien Miller30c3d422000-05-09 11:02:59 +1000818 if (compat20)
819 channel_pre_open_20(c, readset, writeset);
820 else
821 channel_pre_open_15(c, readset, writeset);
Damien Millerb38eff82000-04-01 11:09:21 +1000822 } else if (ret == -1) {
823 debug("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
Damien Millerbd483e72000-04-30 10:00:53 +1000824 chan_read_failed(c); /** force close? */
Damien Millerb38eff82000-04-01 11:09:21 +1000825 chan_write_failed(c);
826 debug("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
827 }
828}
829
Ben Lindstromb3921512001-04-11 15:57:50 +0000830/* try to decode a socks4 header */
Ben Lindstrombba81212001-06-25 05:01:22 +0000831static int
Ben Lindstromb3921512001-04-11 15:57:50 +0000832channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset)
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000833{
834 u_char *p, *host;
Ben Lindstrom2b261b92001-04-17 18:14:34 +0000835 int len, have, i, found;
Ben Lindstromb3921512001-04-11 15:57:50 +0000836 char username[256];
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000837 struct {
838 u_int8_t version;
839 u_int8_t command;
840 u_int16_t dest_port;
Ben Lindstromb3921512001-04-11 15:57:50 +0000841 struct in_addr dest_addr;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000842 } s4_req, s4_rsp;
843
Ben Lindstromb3921512001-04-11 15:57:50 +0000844 debug2("channel %d: decode socks4", c->self);
Ben Lindstrom2b261b92001-04-17 18:14:34 +0000845
846 have = buffer_len(&c->input);
847 len = sizeof(s4_req);
848 if (have < len)
849 return 0;
850 p = buffer_ptr(&c->input);
851 for (found = 0, i = len; i < have; i++) {
852 if (p[i] == '\0') {
853 found = 1;
854 break;
855 }
856 if (i > 1024) {
857 /* the peer is probably sending garbage */
858 debug("channel %d: decode socks4: too long",
859 c->self);
860 return -1;
861 }
862 }
863 if (!found)
864 return 0;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000865 buffer_get(&c->input, (char *)&s4_req.version, 1);
866 buffer_get(&c->input, (char *)&s4_req.command, 1);
867 buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
Ben Lindstromb3921512001-04-11 15:57:50 +0000868 buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
Ben Lindstrom2b261b92001-04-17 18:14:34 +0000869 have = buffer_len(&c->input);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000870 p = buffer_ptr(&c->input);
871 len = strlen(p);
Ben Lindstrom6fa9d102001-04-11 23:08:17 +0000872 debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000873 if (len > have)
Ben Lindstromb3921512001-04-11 15:57:50 +0000874 fatal("channel %d: decode socks4: len %d > have %d",
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000875 c->self, len, have);
876 strlcpy(username, p, sizeof(username));
877 buffer_consume(&c->input, len);
878 buffer_consume(&c->input, 1); /* trailing '\0' */
879
Ben Lindstromb3921512001-04-11 15:57:50 +0000880 host = inet_ntoa(s4_req.dest_addr);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000881 strlcpy(c->path, host, sizeof(c->path));
882 c->host_port = ntohs(s4_req.dest_port);
883
Ben Lindstrom6fa9d102001-04-11 23:08:17 +0000884 debug("channel %d: dynamic request: socks4 host %s port %u command %u",
885 c->self, host, c->host_port, s4_req.command);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000886
Ben Lindstromb3921512001-04-11 15:57:50 +0000887 if (s4_req.command != 1) {
888 debug("channel %d: cannot handle: socks4 cn %d",
889 c->self, s4_req.command);
890 return -1;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000891 }
Ben Lindstromb3921512001-04-11 15:57:50 +0000892 s4_rsp.version = 0; /* vn: 0 for reply */
893 s4_rsp.command = 90; /* cd: req granted */
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000894 s4_rsp.dest_port = 0; /* ignored */
Ben Lindstromb3921512001-04-11 15:57:50 +0000895 s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000896 buffer_append(&c->output, (char *)&s4_rsp, sizeof(s4_rsp));
Ben Lindstromb3921512001-04-11 15:57:50 +0000897 return 1;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000898}
899
Ben Lindstromb3921512001-04-11 15:57:50 +0000900/* dynamic port forwarding */
Ben Lindstrombba81212001-06-25 05:01:22 +0000901static void
Ben Lindstromb3921512001-04-11 15:57:50 +0000902channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset)
903{
904 u_char *p;
905 int have, ret;
906
907 have = buffer_len(&c->input);
908
909 debug2("channel %d: pre_dynamic: have %d", c->self, have);
Ben Lindstromc486d882001-04-11 16:08:34 +0000910 /* buffer_dump(&c->input); */
Ben Lindstromb3921512001-04-11 15:57:50 +0000911 /* check if the fixed size part of the packet is in buffer. */
912 if (have < 4) {
913 /* need more */
914 FD_SET(c->sock, readset);
915 return;
916 }
917 /* try to guess the protocol */
918 p = buffer_ptr(&c->input);
919 switch (p[0]) {
Ben Lindstrom6fa9d102001-04-11 23:08:17 +0000920 case 0x04:
921 ret = channel_decode_socks4(c, readset, writeset);
922 break;
Ben Lindstromb3921512001-04-11 15:57:50 +0000923 default:
924 ret = -1;
925 break;
926 }
927 if (ret < 0) {
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000928 chan_mark_dead(c);
Ben Lindstromb3921512001-04-11 15:57:50 +0000929 } else if (ret == 0) {
930 debug2("channel %d: pre_dynamic: need more", c->self);
931 /* need more */
932 FD_SET(c->sock, readset);
933 } else {
934 /* switch to the next state */
935 c->type = SSH_CHANNEL_OPENING;
936 port_open_helper(c, "direct-tcpip");
937 }
938}
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000939
Damien Millerb38eff82000-04-01 11:09:21 +1000940/* This is our fake X11 server socket. */
Ben Lindstrombba81212001-06-25 05:01:22 +0000941static void
Damien Millerb38eff82000-04-01 11:09:21 +1000942channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset)
943{
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000944 Channel *nc;
Damien Millerb38eff82000-04-01 11:09:21 +1000945 struct sockaddr addr;
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000946 int newsock;
Damien Millerb38eff82000-04-01 11:09:21 +1000947 socklen_t addrlen;
Damien Millerd83ff352001-01-30 09:19:34 +1100948 char buf[16384], *remote_ipaddr;
Damien Millerbd483e72000-04-30 10:00:53 +1000949 int remote_port;
Damien Millerb38eff82000-04-01 11:09:21 +1000950
951 if (FD_ISSET(c->sock, readset)) {
952 debug("X11 connection requested.");
953 addrlen = sizeof(addr);
954 newsock = accept(c->sock, &addr, &addrlen);
955 if (newsock < 0) {
956 error("accept: %.100s", strerror(errno));
957 return;
958 }
Damien Millerd83ff352001-01-30 09:19:34 +1100959 remote_ipaddr = get_peer_ipaddr(newsock);
Damien Millerbd483e72000-04-30 10:00:53 +1000960 remote_port = get_peer_port(newsock);
Damien Millerb38eff82000-04-01 11:09:21 +1000961 snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
Damien Millerd83ff352001-01-30 09:19:34 +1100962 remote_ipaddr, remote_port);
Damien Millerbd483e72000-04-30 10:00:53 +1000963
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000964 nc = channel_new("accepted x11 socket",
Damien Millerbd483e72000-04-30 10:00:53 +1000965 SSH_CHANNEL_OPENING, newsock, newsock, -1,
966 c->local_window_max, c->local_maxpacket,
Damien Miller69b69aa2000-10-28 14:19:58 +1100967 0, xstrdup(buf), 1);
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000968 if (nc == NULL) {
969 close(newsock);
970 xfree(remote_ipaddr);
971 return;
972 }
Damien Millerbd483e72000-04-30 10:00:53 +1000973 if (compat20) {
974 packet_start(SSH2_MSG_CHANNEL_OPEN);
975 packet_put_cstring("x11");
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000976 packet_put_int(nc->self);
Damien Millerbd483e72000-04-30 10:00:53 +1000977 packet_put_int(c->local_window_max);
978 packet_put_int(c->local_maxpacket);
Damien Millerd83ff352001-01-30 09:19:34 +1100979 /* originator ipaddr and port */
980 packet_put_cstring(remote_ipaddr);
Damien Miller30c3d422000-05-09 11:02:59 +1000981 if (datafellows & SSH_BUG_X11FWD) {
982 debug("ssh2 x11 bug compat mode");
983 } else {
984 packet_put_int(remote_port);
985 }
Damien Millerbd483e72000-04-30 10:00:53 +1000986 packet_send();
987 } else {
988 packet_start(SSH_SMSG_X11_OPEN);
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000989 packet_put_int(nc->self);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000990 if (packet_get_protocol_flags() &
991 SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
Ben Lindstrom664408d2001-06-09 01:42:01 +0000992 packet_put_cstring(buf);
Damien Millerbd483e72000-04-30 10:00:53 +1000993 packet_send();
994 }
Damien Millerd83ff352001-01-30 09:19:34 +1100995 xfree(remote_ipaddr);
Damien Millerb38eff82000-04-01 11:09:21 +1000996 }
997}
998
Ben Lindstrombba81212001-06-25 05:01:22 +0000999static void
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001000port_open_helper(Channel *c, char *rtype)
1001{
1002 int direct;
1003 char buf[1024];
1004 char *remote_ipaddr = get_peer_ipaddr(c->sock);
1005 u_short remote_port = get_peer_port(c->sock);
1006
1007 direct = (strcmp(rtype, "direct-tcpip") == 0);
1008
1009 snprintf(buf, sizeof buf,
1010 "%s: listening port %d for %.100s port %d, "
1011 "connect from %.200s port %d",
1012 rtype, c->listening_port, c->path, c->host_port,
1013 remote_ipaddr, remote_port);
1014
1015 xfree(c->remote_name);
1016 c->remote_name = xstrdup(buf);
1017
1018 if (compat20) {
1019 packet_start(SSH2_MSG_CHANNEL_OPEN);
1020 packet_put_cstring(rtype);
1021 packet_put_int(c->self);
1022 packet_put_int(c->local_window_max);
1023 packet_put_int(c->local_maxpacket);
1024 if (direct) {
1025 /* target host, port */
1026 packet_put_cstring(c->path);
1027 packet_put_int(c->host_port);
1028 } else {
1029 /* listen address, port */
1030 packet_put_cstring(c->path);
1031 packet_put_int(c->listening_port);
1032 }
1033 /* originator host and port */
1034 packet_put_cstring(remote_ipaddr);
1035 packet_put_int(remote_port);
1036 packet_send();
1037 } else {
1038 packet_start(SSH_MSG_PORT_OPEN);
1039 packet_put_int(c->self);
1040 packet_put_cstring(c->path);
1041 packet_put_int(c->host_port);
Ben Lindstrome9c99912001-06-09 00:41:05 +00001042 if (packet_get_protocol_flags() &
1043 SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001044 packet_put_cstring(c->remote_name);
1045 packet_send();
1046 }
1047 xfree(remote_ipaddr);
1048}
1049
Damien Millerb38eff82000-04-01 11:09:21 +10001050/*
1051 * This socket is listening for connections to a forwarded TCP/IP port.
1052 */
Ben Lindstrombba81212001-06-25 05:01:22 +00001053static void
Damien Millerb38eff82000-04-01 11:09:21 +10001054channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset)
1055{
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001056 Channel *nc;
Damien Millerb38eff82000-04-01 11:09:21 +10001057 struct sockaddr addr;
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001058 int newsock, nextstate;
Damien Millerb38eff82000-04-01 11:09:21 +10001059 socklen_t addrlen;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001060 char *rtype;
Damien Miller0bc1bd82000-11-13 22:57:25 +11001061
Damien Millerb38eff82000-04-01 11:09:21 +10001062 if (FD_ISSET(c->sock, readset)) {
1063 debug("Connection to port %d forwarding "
1064 "to %.100s port %d requested.",
1065 c->listening_port, c->path, c->host_port);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001066
1067 rtype = (c->type == SSH_CHANNEL_RPORT_LISTENER) ?
1068 "forwarded-tcpip" : "direct-tcpip";
Ben Lindstrom6d618462001-05-10 23:24:49 +00001069 nextstate = (c->host_port == 0 &&
1070 c->type != SSH_CHANNEL_RPORT_LISTENER) ?
1071 SSH_CHANNEL_DYNAMIC : SSH_CHANNEL_OPENING;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001072
Damien Millerb38eff82000-04-01 11:09:21 +10001073 addrlen = sizeof(addr);
1074 newsock = accept(c->sock, &addr, &addrlen);
1075 if (newsock < 0) {
1076 error("accept: %.100s", strerror(errno));
1077 return;
1078 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001079 nc = channel_new(rtype,
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001080 nextstate, newsock, newsock, -1,
Damien Millerb38eff82000-04-01 11:09:21 +10001081 c->local_window_max, c->local_maxpacket,
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001082 0, xstrdup(rtype), 1);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001083 if (nc == NULL) {
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001084 error("channel_post_port_listener: no new channel:");
1085 close(newsock);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001086 return;
Damien Millerb38eff82000-04-01 11:09:21 +10001087 }
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001088 nc->listening_port = c->listening_port;
1089 nc->host_port = c->host_port;
1090 strlcpy(nc->path, c->path, sizeof(nc->path));
1091
1092 if (nextstate != SSH_CHANNEL_DYNAMIC)
1093 port_open_helper(nc, rtype);
Damien Millerb38eff82000-04-01 11:09:21 +10001094 }
1095}
1096
1097/*
1098 * This is the authentication agent socket listening for connections from
1099 * clients.
1100 */
Ben Lindstrombba81212001-06-25 05:01:22 +00001101static void
Damien Millerb38eff82000-04-01 11:09:21 +10001102channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset)
1103{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001104 Channel *nc;
Ben Lindstrome9c99912001-06-09 00:41:05 +00001105 char *name;
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001106 int newsock;
Damien Millerb38eff82000-04-01 11:09:21 +10001107 struct sockaddr addr;
Damien Millerb38eff82000-04-01 11:09:21 +10001108 socklen_t addrlen;
1109
1110 if (FD_ISSET(c->sock, readset)) {
1111 addrlen = sizeof(addr);
1112 newsock = accept(c->sock, &addr, &addrlen);
1113 if (newsock < 0) {
1114 error("accept from auth socket: %.100s", strerror(errno));
1115 return;
1116 }
Ben Lindstrome9c99912001-06-09 00:41:05 +00001117 name = xstrdup("accepted auth socket");
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001118 nc = channel_new("accepted auth socket",
Damien Miller0bc1bd82000-11-13 22:57:25 +11001119 SSH_CHANNEL_OPENING, newsock, newsock, -1,
1120 c->local_window_max, c->local_maxpacket,
Ben Lindstrome9c99912001-06-09 00:41:05 +00001121 0, name, 1);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001122 if (nc == NULL) {
1123 error("channel_post_auth_listener: channel_new failed");
Ben Lindstrome9c99912001-06-09 00:41:05 +00001124 xfree(name);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001125 close(newsock);
1126 }
Damien Miller0bc1bd82000-11-13 22:57:25 +11001127 if (compat20) {
1128 packet_start(SSH2_MSG_CHANNEL_OPEN);
1129 packet_put_cstring("auth-agent@openssh.com");
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001130 packet_put_int(nc->self);
Damien Miller0bc1bd82000-11-13 22:57:25 +11001131 packet_put_int(c->local_window_max);
1132 packet_put_int(c->local_maxpacket);
1133 } else {
1134 packet_start(SSH_SMSG_AGENT_OPEN);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001135 packet_put_int(nc->self);
Damien Miller0bc1bd82000-11-13 22:57:25 +11001136 }
Damien Millerb38eff82000-04-01 11:09:21 +10001137 packet_send();
1138 }
1139}
1140
Ben Lindstrombba81212001-06-25 05:01:22 +00001141static void
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001142channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset)
1143{
Ben Lindstrom69128662001-05-08 20:07:39 +00001144 int err = 0;
1145 int sz = sizeof(err);
1146
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001147 if (FD_ISSET(c->sock, writeset)) {
Ben Lindstrom69128662001-05-08 20:07:39 +00001148 if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, (char *)&err,
1149 &sz) < 0) {
1150 err = errno;
1151 error("getsockopt SO_ERROR failed");
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001152 }
Ben Lindstrom69128662001-05-08 20:07:39 +00001153 if (err == 0) {
1154 debug("channel %d: connected", c->self);
1155 c->type = SSH_CHANNEL_OPEN;
1156 if (compat20) {
1157 packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1158 packet_put_int(c->remote_id);
1159 packet_put_int(c->self);
1160 packet_put_int(c->local_window);
1161 packet_put_int(c->local_maxpacket);
1162 } else {
1163 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1164 packet_put_int(c->remote_id);
1165 packet_put_int(c->self);
1166 }
1167 } else {
1168 debug("channel %d: not connected: %s",
1169 c->self, strerror(err));
1170 if (compat20) {
1171 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1172 packet_put_int(c->remote_id);
1173 packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1174 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1175 packet_put_cstring(strerror(err));
1176 packet_put_cstring("");
1177 }
1178 } else {
1179 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1180 packet_put_int(c->remote_id);
1181 }
1182 chan_mark_dead(c);
1183 }
1184 packet_send();
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001185 }
1186}
1187
Ben Lindstrombba81212001-06-25 05:01:22 +00001188static int
Damien Millerb38eff82000-04-01 11:09:21 +10001189channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset)
1190{
1191 char buf[16*1024];
1192 int len;
1193
Ben Lindstromc0dee1a2001-06-05 20:52:50 +00001194 if (c->rfd != -1 &&
Damien Millerb38eff82000-04-01 11:09:21 +10001195 FD_ISSET(c->rfd, readset)) {
1196 len = read(c->rfd, buf, sizeof(buf));
Damien Miller6f83b8e2000-05-02 09:23:45 +10001197 if (len < 0 && (errno == EINTR || errno == EAGAIN))
1198 return 1;
Damien Millerb38eff82000-04-01 11:09:21 +10001199 if (len <= 0) {
Damien Millerbd483e72000-04-30 10:00:53 +10001200 debug("channel %d: read<=0 rfd %d len %d",
Damien Millerb38eff82000-04-01 11:09:21 +10001201 c->self, c->rfd, len);
Ben Lindstromb3921512001-04-11 15:57:50 +00001202 if (c->type != SSH_CHANNEL_OPEN) {
1203 debug("channel %d: not open", c->self);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001204 chan_mark_dead(c);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001205 return -1;
Ben Lindstromb3921512001-04-11 15:57:50 +00001206 } else if (compat13) {
Damien Millerb38eff82000-04-01 11:09:21 +10001207 buffer_consume(&c->output, buffer_len(&c->output));
1208 c->type = SSH_CHANNEL_INPUT_DRAINING;
Ben Lindstrome9c99912001-06-09 00:41:05 +00001209 debug("channel %d: input draining.", c->self);
Damien Millerb38eff82000-04-01 11:09:21 +10001210 } else {
1211 chan_read_failed(c);
1212 }
1213 return -1;
1214 }
Damien Millerad833b32000-08-23 10:46:23 +10001215 if(c->input_filter != NULL) {
1216 if (c->input_filter(c, buf, len) == -1) {
Ben Lindstromc486d882001-04-11 16:08:34 +00001217 debug("channel %d: filter stops", c->self);
Damien Millerad833b32000-08-23 10:46:23 +10001218 chan_read_failed(c);
1219 }
1220 } else {
1221 buffer_append(&c->input, buf, len);
1222 }
Damien Millerb38eff82000-04-01 11:09:21 +10001223 }
1224 return 1;
1225}
Ben Lindstrombba81212001-06-25 05:01:22 +00001226static int
Damien Millerb38eff82000-04-01 11:09:21 +10001227channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset)
1228{
Ben Lindstrome229b252001-03-05 06:28:06 +00001229 struct termios tio;
Damien Millerb38eff82000-04-01 11:09:21 +10001230 int len;
1231
1232 /* Send buffered output data to the socket. */
Ben Lindstromc0dee1a2001-06-05 20:52:50 +00001233 if (c->wfd != -1 &&
Damien Millerb38eff82000-04-01 11:09:21 +10001234 FD_ISSET(c->wfd, writeset) &&
1235 buffer_len(&c->output) > 0) {
1236 len = write(c->wfd, buffer_ptr(&c->output),
Damien Miller6f83b8e2000-05-02 09:23:45 +10001237 buffer_len(&c->output));
1238 if (len < 0 && (errno == EINTR || errno == EAGAIN))
1239 return 1;
Damien Millerb38eff82000-04-01 11:09:21 +10001240 if (len <= 0) {
Ben Lindstromb3921512001-04-11 15:57:50 +00001241 if (c->type != SSH_CHANNEL_OPEN) {
1242 debug("channel %d: not open", c->self);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001243 chan_mark_dead(c);
Ben Lindstromb3921512001-04-11 15:57:50 +00001244 return -1;
1245 } else if (compat13) {
Damien Millerb38eff82000-04-01 11:09:21 +10001246 buffer_consume(&c->output, buffer_len(&c->output));
Ben Lindstrome9c99912001-06-09 00:41:05 +00001247 debug("channel %d: input draining.", c->self);
Damien Millerb38eff82000-04-01 11:09:21 +10001248 c->type = SSH_CHANNEL_INPUT_DRAINING;
1249 } else {
1250 chan_write_failed(c);
1251 }
1252 return -1;
1253 }
Damien Miller79438cc2001-02-16 12:34:57 +11001254 if (compat20 && c->isatty) {
Damien Miller79438cc2001-02-16 12:34:57 +11001255 if (tcgetattr(c->wfd, &tio) == 0 &&
1256 !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1257 /*
1258 * Simulate echo to reduce the impact of
Ben Lindstromb40204b2001-03-05 06:29:44 +00001259 * traffic analysis. We need to match the
Ben Lindstrome229b252001-03-05 06:28:06 +00001260 * size of a SSH2_MSG_CHANNEL_DATA message
1261 * (4 byte channel id + data)
Damien Miller79438cc2001-02-16 12:34:57 +11001262 */
Ben Lindstrome229b252001-03-05 06:28:06 +00001263 packet_send_ignore(4 + len);
Damien Miller79438cc2001-02-16 12:34:57 +11001264 packet_send();
Damien Miller79438cc2001-02-16 12:34:57 +11001265 }
1266 }
Damien Millerb38eff82000-04-01 11:09:21 +10001267 buffer_consume(&c->output, len);
Damien Miller33b13562000-04-04 14:38:59 +10001268 if (compat20 && len > 0) {
1269 c->local_consumed += len;
1270 }
1271 }
1272 return 1;
1273}
Ben Lindstrombba81212001-06-25 05:01:22 +00001274static int
Damien Miller33b13562000-04-04 14:38:59 +10001275channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset)
1276{
1277 char buf[16*1024];
1278 int len;
1279
Damien Miller1383bd82000-04-06 12:32:37 +10001280/** XXX handle drain efd, too */
Damien Miller33b13562000-04-04 14:38:59 +10001281 if (c->efd != -1) {
1282 if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1283 FD_ISSET(c->efd, writeset) &&
1284 buffer_len(&c->extended) > 0) {
1285 len = write(c->efd, buffer_ptr(&c->extended),
1286 buffer_len(&c->extended));
Damien Millerd3444942000-09-30 14:20:03 +11001287 debug2("channel %d: written %d to efd %d",
Damien Miller33b13562000-04-04 14:38:59 +10001288 c->self, len, c->efd);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001289 if (len < 0 && (errno == EINTR || errno == EAGAIN))
1290 return 1;
1291 if (len <= 0) {
1292 debug2("channel %d: closing write-efd %d",
1293 c->self, c->efd);
1294 close(c->efd);
1295 c->efd = -1;
1296 } else {
Damien Miller33b13562000-04-04 14:38:59 +10001297 buffer_consume(&c->extended, len);
1298 c->local_consumed += len;
1299 }
1300 } else if (c->extended_usage == CHAN_EXTENDED_READ &&
1301 FD_ISSET(c->efd, readset)) {
1302 len = read(c->efd, buf, sizeof(buf));
Damien Millerd3444942000-09-30 14:20:03 +11001303 debug2("channel %d: read %d from efd %d",
Damien Miller33b13562000-04-04 14:38:59 +10001304 c->self, len, c->efd);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001305 if (len < 0 && (errno == EINTR || errno == EAGAIN))
1306 return 1;
1307 if (len <= 0) {
1308 debug2("channel %d: closing read-efd %d",
Damien Miller1383bd82000-04-06 12:32:37 +10001309 c->self, c->efd);
1310 close(c->efd);
1311 c->efd = -1;
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001312 } else {
Damien Miller33b13562000-04-04 14:38:59 +10001313 buffer_append(&c->extended, buf, len);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001314 }
Damien Miller33b13562000-04-04 14:38:59 +10001315 }
1316 }
1317 return 1;
1318}
Ben Lindstrombba81212001-06-25 05:01:22 +00001319static int
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001320channel_check_window(Channel *c)
Damien Miller33b13562000-04-04 14:38:59 +10001321{
Ben Lindstromb3921512001-04-11 15:57:50 +00001322 if (c->type == SSH_CHANNEL_OPEN &&
1323 !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
Damien Miller33b13562000-04-04 14:38:59 +10001324 c->local_window < c->local_window_max/2 &&
1325 c->local_consumed > 0) {
1326 packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1327 packet_put_int(c->remote_id);
1328 packet_put_int(c->local_consumed);
1329 packet_send();
Damien Millerd3444942000-09-30 14:20:03 +11001330 debug2("channel %d: window %d sent adjust %d",
Damien Miller33b13562000-04-04 14:38:59 +10001331 c->self, c->local_window,
1332 c->local_consumed);
1333 c->local_window += c->local_consumed;
1334 c->local_consumed = 0;
Damien Millerb38eff82000-04-01 11:09:21 +10001335 }
1336 return 1;
1337}
1338
Ben Lindstrombba81212001-06-25 05:01:22 +00001339static void
Damien Millerb38eff82000-04-01 11:09:21 +10001340channel_post_open_1(Channel *c, fd_set * readset, fd_set * writeset)
1341{
1342 channel_handle_rfd(c, readset, writeset);
1343 channel_handle_wfd(c, readset, writeset);
1344}
1345
Ben Lindstrombba81212001-06-25 05:01:22 +00001346static void
Damien Miller33b13562000-04-04 14:38:59 +10001347channel_post_open_2(Channel *c, fd_set * readset, fd_set * writeset)
1348{
1349 channel_handle_rfd(c, readset, writeset);
1350 channel_handle_wfd(c, readset, writeset);
1351 channel_handle_efd(c, readset, writeset);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001352
1353 channel_check_window(c);
Damien Miller33b13562000-04-04 14:38:59 +10001354}
1355
Ben Lindstrombba81212001-06-25 05:01:22 +00001356static void
Damien Millerb38eff82000-04-01 11:09:21 +10001357channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset)
1358{
1359 int len;
1360 /* Send buffered output data to the socket. */
1361 if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
1362 len = write(c->sock, buffer_ptr(&c->output),
1363 buffer_len(&c->output));
1364 if (len <= 0)
1365 buffer_consume(&c->output, buffer_len(&c->output));
1366 else
1367 buffer_consume(&c->output, len);
1368 }
1369}
1370
Ben Lindstrombba81212001-06-25 05:01:22 +00001371static void
Damien Miller33b13562000-04-04 14:38:59 +10001372channel_handler_init_20(void)
1373{
1374 channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_20;
Damien Millerbd483e72000-04-30 10:00:53 +10001375 channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
Damien Miller33b13562000-04-04 14:38:59 +10001376 channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
Damien Miller0bc1bd82000-11-13 22:57:25 +11001377 channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
Damien Millerbd483e72000-04-30 10:00:53 +10001378 channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
Damien Miller0bc1bd82000-11-13 22:57:25 +11001379 channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001380 channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001381 channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
Damien Miller33b13562000-04-04 14:38:59 +10001382
1383 channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_2;
1384 channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
Damien Miller0bc1bd82000-11-13 22:57:25 +11001385 channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
Damien Millerbd483e72000-04-30 10:00:53 +10001386 channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
Damien Miller0bc1bd82000-11-13 22:57:25 +11001387 channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001388 channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
Ben Lindstromb3921512001-04-11 15:57:50 +00001389 channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_2;
Damien Miller33b13562000-04-04 14:38:59 +10001390}
1391
Ben Lindstrombba81212001-06-25 05:01:22 +00001392static void
Damien Millerb38eff82000-04-01 11:09:21 +10001393channel_handler_init_13(void)
1394{
1395 channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
1396 channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
1397 channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1398 channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1399 channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1400 channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
1401 channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001402 channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001403 channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
Damien Millerb38eff82000-04-01 11:09:21 +10001404
1405 channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1;
1406 channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1407 channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1408 channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1409 channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001410 channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
Ben Lindstromb3921512001-04-11 15:57:50 +00001411 channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1;
Damien Millerb38eff82000-04-01 11:09:21 +10001412}
1413
Ben Lindstrombba81212001-06-25 05:01:22 +00001414static void
Damien Millerb38eff82000-04-01 11:09:21 +10001415channel_handler_init_15(void)
1416{
1417 channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_15;
Damien Millerbd483e72000-04-30 10:00:53 +10001418 channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
Damien Millerb38eff82000-04-01 11:09:21 +10001419 channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1420 channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1421 channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001422 channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001423 channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
Damien Millerb38eff82000-04-01 11:09:21 +10001424
1425 channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1426 channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1427 channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1428 channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001429 channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
Ben Lindstromb3921512001-04-11 15:57:50 +00001430 channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1;
Damien Millerb38eff82000-04-01 11:09:21 +10001431}
1432
Ben Lindstrombba81212001-06-25 05:01:22 +00001433static void
Damien Millerb38eff82000-04-01 11:09:21 +10001434channel_handler_init(void)
1435{
1436 int i;
1437 for(i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
1438 channel_pre[i] = NULL;
1439 channel_post[i] = NULL;
1440 }
Damien Miller33b13562000-04-04 14:38:59 +10001441 if (compat20)
1442 channel_handler_init_20();
1443 else if (compat13)
Damien Millerb38eff82000-04-01 11:09:21 +10001444 channel_handler_init_13();
1445 else
1446 channel_handler_init_15();
1447}
1448
Ben Lindstrombba81212001-06-25 05:01:22 +00001449static void
Damien Millerb38eff82000-04-01 11:09:21 +10001450channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset)
1451{
1452 static int did_init = 0;
1453 int i;
1454 Channel *c;
1455
1456 if (!did_init) {
1457 channel_handler_init();
1458 did_init = 1;
1459 }
1460 for (i = 0; i < channels_alloc; i++) {
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001461 c = channels[i];
1462 if (c == NULL)
Damien Millerb38eff82000-04-01 11:09:21 +10001463 continue;
Ben Lindstromc0dee1a2001-06-05 20:52:50 +00001464 if (ftab[c->type] != NULL)
1465 (*ftab[c->type])(c, readset, writeset);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001466 if (chan_is_dead(c)) {
1467 /*
1468 * we have to remove the fd's from the select mask
1469 * before the channels are free'd and the fd's are
1470 * closed
1471 */
1472 if (c->wfd != -1)
1473 FD_CLR(c->wfd, writeset);
1474 if (c->rfd != -1)
1475 FD_CLR(c->rfd, readset);
1476 if (c->efd != -1) {
1477 if (c->extended_usage == CHAN_EXTENDED_READ)
1478 FD_CLR(c->efd, readset);
1479 if (c->extended_usage == CHAN_EXTENDED_WRITE)
1480 FD_CLR(c->efd, writeset);
1481 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001482 channel_free(c);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001483 }
Damien Millerb38eff82000-04-01 11:09:21 +10001484 }
1485}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001486
Ben Lindstrome9c99912001-06-09 00:41:05 +00001487/*
1488 * Allocate/update select bitmasks and add any bits relevant to channels in
1489 * select bitmasks.
1490 */
Damien Miller4af51302000-04-16 11:18:38 +10001491void
Ben Lindstrombe2cc432001-04-04 23:46:07 +00001492channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
1493 int rekeying)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001494{
Damien Miller5e953212001-01-30 09:14:00 +11001495 int n;
1496 u_int sz;
1497
1498 n = MAX(*maxfdp, channel_max_fd);
1499
1500 sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
1501 if (*readsetp == NULL || n > *maxfdp) {
1502 if (*readsetp)
1503 xfree(*readsetp);
1504 if (*writesetp)
1505 xfree(*writesetp);
1506 *readsetp = xmalloc(sz);
1507 *writesetp = xmalloc(sz);
1508 *maxfdp = n;
1509 }
1510 memset(*readsetp, 0, sz);
1511 memset(*writesetp, 0, sz);
1512
Ben Lindstrombe2cc432001-04-04 23:46:07 +00001513 if (!rekeying)
1514 channel_handler(channel_pre, *readsetp, *writesetp);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001515}
1516
Ben Lindstrome9c99912001-06-09 00:41:05 +00001517/*
1518 * After select, perform any appropriate operations for channels which have
1519 * events pending.
1520 */
Damien Miller4af51302000-04-16 11:18:38 +10001521void
Damien Miller95def091999-11-25 00:26:21 +11001522channel_after_select(fd_set * readset, fd_set * writeset)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001523{
Damien Millerb38eff82000-04-01 11:09:21 +10001524 channel_handler(channel_post, readset, writeset);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001525}
1526
Ben Lindstrome9c99912001-06-09 00:41:05 +00001527
Damien Miller5e953212001-01-30 09:14:00 +11001528/* If there is data to send to the connection, enqueue some of it now. */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001529
Damien Miller4af51302000-04-16 11:18:38 +10001530void
Damien Miller95def091999-11-25 00:26:21 +11001531channel_output_poll()
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001532{
Damien Miller95def091999-11-25 00:26:21 +11001533 int len, i;
Damien Millerb38eff82000-04-01 11:09:21 +10001534 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001535
Damien Miller95def091999-11-25 00:26:21 +11001536 for (i = 0; i < channels_alloc; i++) {
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001537 c = channels[i];
1538 if (c == NULL)
1539 continue;
Damien Miller34132e52000-01-14 15:45:46 +11001540
Ben Lindstrome9c99912001-06-09 00:41:05 +00001541 /*
1542 * We are only interested in channels that can have buffered
1543 * incoming data.
1544 */
Damien Miller34132e52000-01-14 15:45:46 +11001545 if (compat13) {
Damien Millerb38eff82000-04-01 11:09:21 +10001546 if (c->type != SSH_CHANNEL_OPEN &&
1547 c->type != SSH_CHANNEL_INPUT_DRAINING)
Damien Miller34132e52000-01-14 15:45:46 +11001548 continue;
1549 } else {
Damien Millerb38eff82000-04-01 11:09:21 +10001550 if (c->type != SSH_CHANNEL_OPEN)
Damien Miller34132e52000-01-14 15:45:46 +11001551 continue;
Damien Miller34132e52000-01-14 15:45:46 +11001552 }
Damien Millerefb4afe2000-04-12 18:45:05 +10001553 if (compat20 &&
1554 (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001555 /* XXX is this true? */
Ben Lindstromb1131e92001-03-05 07:27:13 +00001556 debug2("channel %d: no data after CLOSE", c->self);
Damien Miller33b13562000-04-04 14:38:59 +10001557 continue;
1558 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001559
Damien Miller95def091999-11-25 00:26:21 +11001560 /* Get the amount of buffered data for this channel. */
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001561 if ((c->istate == CHAN_INPUT_OPEN ||
1562 c->istate == CHAN_INPUT_WAIT_DRAIN) &&
1563 (len = buffer_len(&c->input)) > 0) {
Ben Lindstrome9c99912001-06-09 00:41:05 +00001564 /*
1565 * Send some data for the other side over the secure
1566 * connection.
1567 */
Damien Miller33b13562000-04-04 14:38:59 +10001568 if (compat20) {
1569 if (len > c->remote_window)
1570 len = c->remote_window;
1571 if (len > c->remote_maxpacket)
1572 len = c->remote_maxpacket;
Damien Miller95def091999-11-25 00:26:21 +11001573 } else {
Damien Miller33b13562000-04-04 14:38:59 +10001574 if (packet_is_interactive()) {
1575 if (len > 1024)
1576 len = 512;
1577 } else {
1578 /* Keep the packets at reasonable size. */
1579 if (len > packet_get_maxsize()/2)
1580 len = packet_get_maxsize()/2;
1581 }
Damien Miller95def091999-11-25 00:26:21 +11001582 }
Damien Millerb38eff82000-04-01 11:09:21 +10001583 if (len > 0) {
Damien Miller33b13562000-04-04 14:38:59 +10001584 packet_start(compat20 ?
1585 SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
Damien Millerb38eff82000-04-01 11:09:21 +10001586 packet_put_int(c->remote_id);
1587 packet_put_string(buffer_ptr(&c->input), len);
1588 packet_send();
1589 buffer_consume(&c->input, len);
1590 c->remote_window -= len;
Damien Millerb38eff82000-04-01 11:09:21 +10001591 }
1592 } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
Damien Miller95def091999-11-25 00:26:21 +11001593 if (compat13)
1594 fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
Damien Miller5428f641999-11-25 11:54:57 +11001595 /*
1596 * input-buffer is empty and read-socket shutdown:
1597 * tell peer, that we will not send more data: send IEOF
1598 */
Damien Millerb38eff82000-04-01 11:09:21 +10001599 chan_ibuf_empty(c);
Damien Miller95def091999-11-25 00:26:21 +11001600 }
Damien Miller33b13562000-04-04 14:38:59 +10001601 /* Send extended data, i.e. stderr */
1602 if (compat20 &&
1603 c->remote_window > 0 &&
1604 (len = buffer_len(&c->extended)) > 0 &&
1605 c->extended_usage == CHAN_EXTENDED_READ) {
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001606 debug2("channel %d: rwin %d elen %d euse %d",
1607 c->self, c->remote_window, buffer_len(&c->extended),
1608 c->extended_usage);
Damien Miller33b13562000-04-04 14:38:59 +10001609 if (len > c->remote_window)
1610 len = c->remote_window;
1611 if (len > c->remote_maxpacket)
1612 len = c->remote_maxpacket;
1613 packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
1614 packet_put_int(c->remote_id);
1615 packet_put_int(SSH2_EXTENDED_DATA_STDERR);
1616 packet_put_string(buffer_ptr(&c->extended), len);
1617 packet_send();
1618 buffer_consume(&c->extended, len);
1619 c->remote_window -= len;
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001620 debug2("channel %d: sent ext data %d", c->self, len);
Damien Miller33b13562000-04-04 14:38:59 +10001621 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001622 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001623}
1624
Ben Lindstrome9c99912001-06-09 00:41:05 +00001625
1626/* -- protocol input */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001627
Damien Miller4af51302000-04-16 11:18:38 +10001628void
Damien Miller62cee002000-09-23 17:15:56 +11001629channel_input_data(int type, int plen, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001630{
Damien Miller34132e52000-01-14 15:45:46 +11001631 int id;
Damien Miller95def091999-11-25 00:26:21 +11001632 char *data;
Ben Lindstrom46c16222000-12-22 01:43:59 +00001633 u_int data_len;
Damien Millerb38eff82000-04-01 11:09:21 +10001634 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001635
Damien Miller95def091999-11-25 00:26:21 +11001636 /* Get the channel number and verify it. */
Damien Miller34132e52000-01-14 15:45:46 +11001637 id = packet_get_int();
Damien Millerb38eff82000-04-01 11:09:21 +10001638 c = channel_lookup(id);
1639 if (c == NULL)
Damien Miller34132e52000-01-14 15:45:46 +11001640 packet_disconnect("Received data for nonexistent channel %d.", id);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001641
Damien Miller95def091999-11-25 00:26:21 +11001642 /* Ignore any data for non-open channels (might happen on close) */
Damien Millerb38eff82000-04-01 11:09:21 +10001643 if (c->type != SSH_CHANNEL_OPEN &&
1644 c->type != SSH_CHANNEL_X11_OPEN)
Damien Miller34132e52000-01-14 15:45:46 +11001645 return;
1646
1647 /* same for protocol 1.5 if output end is no longer open */
Damien Millerb38eff82000-04-01 11:09:21 +10001648 if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN)
Damien Miller95def091999-11-25 00:26:21 +11001649 return;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001650
Damien Miller95def091999-11-25 00:26:21 +11001651 /* Get the data. */
1652 data = packet_get_string(&data_len);
Damien Miller4af51302000-04-16 11:18:38 +10001653 packet_done();
Damien Millerb38eff82000-04-01 11:09:21 +10001654
Damien Miller33b13562000-04-04 14:38:59 +10001655 if (compat20){
1656 if (data_len > c->local_maxpacket) {
1657 log("channel %d: rcvd big packet %d, maxpack %d",
1658 c->self, data_len, c->local_maxpacket);
1659 }
1660 if (data_len > c->local_window) {
1661 log("channel %d: rcvd too much data %d, win %d",
1662 c->self, data_len, c->local_window);
1663 xfree(data);
1664 return;
1665 }
1666 c->local_window -= data_len;
1667 }else{
1668 packet_integrity_check(plen, 4 + 4 + data_len, type);
1669 }
Damien Millerb38eff82000-04-01 11:09:21 +10001670 buffer_append(&c->output, data, data_len);
Damien Miller95def091999-11-25 00:26:21 +11001671 xfree(data);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001672}
Ben Lindstrome9c99912001-06-09 00:41:05 +00001673
Damien Miller4af51302000-04-16 11:18:38 +10001674void
Damien Miller62cee002000-09-23 17:15:56 +11001675channel_input_extended_data(int type, int plen, void *ctxt)
Damien Miller33b13562000-04-04 14:38:59 +10001676{
1677 int id;
1678 int tcode;
1679 char *data;
Ben Lindstrom46c16222000-12-22 01:43:59 +00001680 u_int data_len;
Damien Miller33b13562000-04-04 14:38:59 +10001681 Channel *c;
1682
1683 /* Get the channel number and verify it. */
1684 id = packet_get_int();
1685 c = channel_lookup(id);
1686
1687 if (c == NULL)
1688 packet_disconnect("Received extended_data for bad channel %d.", id);
1689 if (c->type != SSH_CHANNEL_OPEN) {
1690 log("channel %d: ext data for non open", id);
1691 return;
1692 }
1693 tcode = packet_get_int();
1694 if (c->efd == -1 ||
1695 c->extended_usage != CHAN_EXTENDED_WRITE ||
1696 tcode != SSH2_EXTENDED_DATA_STDERR) {
1697 log("channel %d: bad ext data", c->self);
1698 return;
1699 }
1700 data = packet_get_string(&data_len);
Damien Miller4af51302000-04-16 11:18:38 +10001701 packet_done();
Damien Miller33b13562000-04-04 14:38:59 +10001702 if (data_len > c->local_window) {
1703 log("channel %d: rcvd too much extended_data %d, win %d",
1704 c->self, data_len, c->local_window);
1705 xfree(data);
1706 return;
1707 }
Damien Millerd3444942000-09-30 14:20:03 +11001708 debug2("channel %d: rcvd ext data %d", c->self, data_len);
Damien Miller33b13562000-04-04 14:38:59 +10001709 c->local_window -= data_len;
1710 buffer_append(&c->extended, data, data_len);
1711 xfree(data);
1712}
1713
Damien Miller4af51302000-04-16 11:18:38 +10001714void
Damien Miller62cee002000-09-23 17:15:56 +11001715channel_input_ieof(int type, int plen, void *ctxt)
Damien Millerb38eff82000-04-01 11:09:21 +10001716{
1717 int id;
1718 Channel *c;
1719
1720 packet_integrity_check(plen, 4, type);
1721
1722 id = packet_get_int();
1723 c = channel_lookup(id);
1724 if (c == NULL)
1725 packet_disconnect("Received ieof for nonexistent channel %d.", id);
1726 chan_rcvd_ieof(c);
1727}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001728
Damien Miller4af51302000-04-16 11:18:38 +10001729void
Damien Miller62cee002000-09-23 17:15:56 +11001730channel_input_close(int type, int plen, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001731{
Damien Millerb38eff82000-04-01 11:09:21 +10001732 int id;
1733 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001734
Damien Millerb38eff82000-04-01 11:09:21 +10001735 packet_integrity_check(plen, 4, type);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001736
Damien Millerb38eff82000-04-01 11:09:21 +10001737 id = packet_get_int();
1738 c = channel_lookup(id);
1739 if (c == NULL)
1740 packet_disconnect("Received close for nonexistent channel %d.", id);
Damien Miller5428f641999-11-25 11:54:57 +11001741
1742 /*
1743 * Send a confirmation that we have closed the channel and no more
1744 * data is coming for it.
1745 */
Damien Miller95def091999-11-25 00:26:21 +11001746 packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
Damien Millerb38eff82000-04-01 11:09:21 +10001747 packet_put_int(c->remote_id);
Damien Miller95def091999-11-25 00:26:21 +11001748 packet_send();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001749
Damien Miller5428f641999-11-25 11:54:57 +11001750 /*
1751 * If the channel is in closed state, we have sent a close request,
1752 * and the other side will eventually respond with a confirmation.
1753 * Thus, we cannot free the channel here, because then there would be
1754 * no-one to receive the confirmation. The channel gets freed when
1755 * the confirmation arrives.
1756 */
Damien Millerb38eff82000-04-01 11:09:21 +10001757 if (c->type != SSH_CHANNEL_CLOSED) {
Damien Miller5428f641999-11-25 11:54:57 +11001758 /*
1759 * Not a closed channel - mark it as draining, which will
1760 * cause it to be freed later.
1761 */
Damien Millerb38eff82000-04-01 11:09:21 +10001762 buffer_consume(&c->input, buffer_len(&c->input));
1763 c->type = SSH_CHANNEL_OUTPUT_DRAINING;
Damien Miller95def091999-11-25 00:26:21 +11001764 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001765}
1766
Damien Millerb38eff82000-04-01 11:09:21 +10001767/* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
Damien Miller4af51302000-04-16 11:18:38 +10001768void
Damien Miller62cee002000-09-23 17:15:56 +11001769channel_input_oclose(int type, int plen, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001770{
Damien Millerb38eff82000-04-01 11:09:21 +10001771 int id = packet_get_int();
1772 Channel *c = channel_lookup(id);
1773 packet_integrity_check(plen, 4, type);
1774 if (c == NULL)
1775 packet_disconnect("Received oclose for nonexistent channel %d.", id);
1776 chan_rcvd_oclose(c);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001777}
1778
Damien Miller4af51302000-04-16 11:18:38 +10001779void
Damien Miller62cee002000-09-23 17:15:56 +11001780channel_input_close_confirmation(int type, int plen, void *ctxt)
Damien Millerb38eff82000-04-01 11:09:21 +10001781{
1782 int id = packet_get_int();
1783 Channel *c = channel_lookup(id);
1784
Damien Miller4af51302000-04-16 11:18:38 +10001785 packet_done();
Damien Millerb38eff82000-04-01 11:09:21 +10001786 if (c == NULL)
1787 packet_disconnect("Received close confirmation for "
1788 "out-of-range channel %d.", id);
1789 if (c->type != SSH_CHANNEL_CLOSED)
1790 packet_disconnect("Received close confirmation for "
1791 "non-closed channel %d (type %d).", id, c->type);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001792 channel_free(c);
Damien Millerb38eff82000-04-01 11:09:21 +10001793}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001794
Damien Miller4af51302000-04-16 11:18:38 +10001795void
Damien Miller62cee002000-09-23 17:15:56 +11001796channel_input_open_confirmation(int type, int plen, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001797{
Damien Millerb38eff82000-04-01 11:09:21 +10001798 int id, remote_id;
1799 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001800
Damien Miller33b13562000-04-04 14:38:59 +10001801 if (!compat20)
1802 packet_integrity_check(plen, 4 + 4, type);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001803
Damien Millerb38eff82000-04-01 11:09:21 +10001804 id = packet_get_int();
1805 c = channel_lookup(id);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001806
Damien Millerb38eff82000-04-01 11:09:21 +10001807 if (c==NULL || c->type != SSH_CHANNEL_OPENING)
1808 packet_disconnect("Received open confirmation for "
1809 "non-opening channel %d.", id);
1810 remote_id = packet_get_int();
Damien Miller5428f641999-11-25 11:54:57 +11001811 /* Record the remote channel number and mark that the channel is now open. */
Damien Millerb38eff82000-04-01 11:09:21 +10001812 c->remote_id = remote_id;
1813 c->type = SSH_CHANNEL_OPEN;
Damien Miller33b13562000-04-04 14:38:59 +10001814
1815 if (compat20) {
1816 c->remote_window = packet_get_int();
1817 c->remote_maxpacket = packet_get_int();
Damien Miller4af51302000-04-16 11:18:38 +10001818 packet_done();
Damien Miller33b13562000-04-04 14:38:59 +10001819 if (c->cb_fn != NULL && c->cb_event == type) {
Damien Millerd3444942000-09-30 14:20:03 +11001820 debug2("callback start");
Damien Miller33b13562000-04-04 14:38:59 +10001821 c->cb_fn(c->self, c->cb_arg);
Damien Millerd3444942000-09-30 14:20:03 +11001822 debug2("callback done");
Damien Miller33b13562000-04-04 14:38:59 +10001823 }
1824 debug("channel %d: open confirm rwindow %d rmax %d", c->self,
1825 c->remote_window, c->remote_maxpacket);
1826 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001827}
1828
Ben Lindstrombba81212001-06-25 05:01:22 +00001829static char *
Ben Lindstrom69128662001-05-08 20:07:39 +00001830reason2txt(int reason)
1831{
1832 switch(reason) {
1833 case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
1834 return "administratively prohibited";
1835 case SSH2_OPEN_CONNECT_FAILED:
1836 return "connect failed";
1837 case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
1838 return "unknown channel type";
1839 case SSH2_OPEN_RESOURCE_SHORTAGE:
1840 return "resource shortage";
1841 }
Ben Lindstrome2595442001-06-05 20:01:39 +00001842 return "unknown reason";
Ben Lindstrom69128662001-05-08 20:07:39 +00001843}
1844
Damien Miller4af51302000-04-16 11:18:38 +10001845void
Damien Miller62cee002000-09-23 17:15:56 +11001846channel_input_open_failure(int type, int plen, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001847{
Kevin Steves12057502001-02-05 14:54:34 +00001848 int id, reason;
1849 char *msg = NULL, *lang = NULL;
Damien Millerb38eff82000-04-01 11:09:21 +10001850 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001851
Damien Miller33b13562000-04-04 14:38:59 +10001852 if (!compat20)
1853 packet_integrity_check(plen, 4, type);
Damien Millerb38eff82000-04-01 11:09:21 +10001854
1855 id = packet_get_int();
1856 c = channel_lookup(id);
1857
1858 if (c==NULL || c->type != SSH_CHANNEL_OPENING)
1859 packet_disconnect("Received open failure for "
1860 "non-opening channel %d.", id);
Damien Miller33b13562000-04-04 14:38:59 +10001861 if (compat20) {
Kevin Steves12057502001-02-05 14:54:34 +00001862 reason = packet_get_int();
Ben Lindstromf3436742001-04-29 19:52:00 +00001863 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
Kevin Steves12057502001-02-05 14:54:34 +00001864 msg = packet_get_string(NULL);
1865 lang = packet_get_string(NULL);
1866 }
Damien Miller4af51302000-04-16 11:18:38 +10001867 packet_done();
Ben Lindstrom69128662001-05-08 20:07:39 +00001868 log("channel %d: open failed: %s%s%s", id,
1869 reason2txt(reason), msg ? ": ": "", msg ? msg : "");
Kevin Steves12057502001-02-05 14:54:34 +00001870 if (msg != NULL)
1871 xfree(msg);
1872 if (lang != NULL)
1873 xfree(lang);
Damien Miller33b13562000-04-04 14:38:59 +10001874 }
Damien Miller95def091999-11-25 00:26:21 +11001875 /* Free the channel. This will also close the socket. */
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001876 channel_free(c);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001877}
1878
Damien Miller33b13562000-04-04 14:38:59 +10001879void
Damien Miller62cee002000-09-23 17:15:56 +11001880channel_input_channel_request(int type, int plen, void *ctxt)
Damien Miller33b13562000-04-04 14:38:59 +10001881{
1882 int id;
1883 Channel *c;
1884
1885 id = packet_get_int();
1886 c = channel_lookup(id);
1887
1888 if (c == NULL ||
1889 (c->type != SSH_CHANNEL_OPEN && c->type != SSH_CHANNEL_LARVAL))
1890 packet_disconnect("Received request for "
1891 "non-open channel %d.", id);
1892 if (c->cb_fn != NULL && c->cb_event == type) {
Damien Millerd3444942000-09-30 14:20:03 +11001893 debug2("callback start");
Damien Miller33b13562000-04-04 14:38:59 +10001894 c->cb_fn(c->self, c->cb_arg);
Damien Millerd3444942000-09-30 14:20:03 +11001895 debug2("callback done");
Damien Miller33b13562000-04-04 14:38:59 +10001896 } else {
1897 char *service = packet_get_string(NULL);
Ben Lindstromcc74df72001-03-05 06:20:14 +00001898 debug("channel %d: rcvd request for %s", c->self, service);
Damien Millerd3444942000-09-30 14:20:03 +11001899 debug("cb_fn %p cb_event %d", c->cb_fn , c->cb_event);
Damien Miller33b13562000-04-04 14:38:59 +10001900 xfree(service);
1901 }
1902}
1903
Damien Miller4af51302000-04-16 11:18:38 +10001904void
Damien Miller62cee002000-09-23 17:15:56 +11001905channel_input_window_adjust(int type, int plen, void *ctxt)
Damien Miller33b13562000-04-04 14:38:59 +10001906{
1907 Channel *c;
1908 int id, adjust;
1909
1910 if (!compat20)
1911 return;
1912
1913 /* Get the channel number and verify it. */
1914 id = packet_get_int();
1915 c = channel_lookup(id);
1916
1917 if (c == NULL || c->type != SSH_CHANNEL_OPEN) {
1918 log("Received window adjust for "
1919 "non-open channel %d.", id);
1920 return;
1921 }
1922 adjust = packet_get_int();
Damien Miller4af51302000-04-16 11:18:38 +10001923 packet_done();
Damien Millerd3444942000-09-30 14:20:03 +11001924 debug2("channel %d: rcvd adjust %d", id, adjust);
Damien Miller33b13562000-04-04 14:38:59 +10001925 c->remote_window += adjust;
1926}
1927
Damien Miller4af51302000-04-16 11:18:38 +10001928void
Ben Lindstrome9c99912001-06-09 00:41:05 +00001929channel_input_port_open(int type, int plen, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001930{
Ben Lindstrome9c99912001-06-09 00:41:05 +00001931 Channel *c = NULL;
1932 u_short host_port;
1933 char *host, *originator_string;
1934 int remote_id, sock = -1;
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001935
Ben Lindstrome9c99912001-06-09 00:41:05 +00001936 remote_id = packet_get_int();
1937 host = packet_get_string(NULL);
1938 host_port = packet_get_int();
1939
1940 if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
1941 originator_string = packet_get_string(NULL);
1942 } else {
1943 originator_string = xstrdup("unknown (remote did not supply name)");
1944 }
1945 packet_done();
1946 sock = channel_connect_to(host, host_port);
1947 if (sock != -1) {
1948 c = channel_new("connected socket",
1949 SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0,
1950 originator_string, 1);
1951 if (c == NULL) {
1952 error("channel_input_port_open: channel_new failed");
1953 close(sock);
1954 } else {
1955 c->remote_id = remote_id;
Damien Miller95def091999-11-25 00:26:21 +11001956 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001957 }
Ben Lindstrome9c99912001-06-09 00:41:05 +00001958 if (c == NULL) {
1959 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1960 packet_put_int(remote_id);
1961 packet_send();
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001962 }
Ben Lindstrome9c99912001-06-09 00:41:05 +00001963 xfree(host);
Ben Lindstrom5744dc42001-04-13 23:28:01 +00001964}
1965
1966
Ben Lindstrome9c99912001-06-09 00:41:05 +00001967/* -- tcp forwarding */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001968
Damien Miller5428f641999-11-25 11:54:57 +11001969/*
1970 * Initiate forwarding of connections to local port "port" through the secure
1971 * channel to host:port from remote side.
1972 */
Kevin Steves12057502001-02-05 14:54:34 +00001973int
Damien Miller0bc1bd82000-11-13 22:57:25 +11001974channel_request_local_forwarding(u_short listen_port, const char *host_to_connect,
1975 u_short port_to_connect, int gateway_ports)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001976{
Kevin Steves12057502001-02-05 14:54:34 +00001977 return channel_request_forwarding(
Damien Miller0bc1bd82000-11-13 22:57:25 +11001978 NULL, listen_port,
1979 host_to_connect, port_to_connect,
1980 gateway_ports, /*remote_fwd*/ 0);
1981}
1982
1983/*
1984 * If 'remote_fwd' is true we have a '-R style' listener for protocol 2
1985 * (SSH_CHANNEL_RPORT_LISTENER).
1986 */
Kevin Steves12057502001-02-05 14:54:34 +00001987int
Damien Miller0bc1bd82000-11-13 22:57:25 +11001988channel_request_forwarding(
1989 const char *listen_address, u_short listen_port,
1990 const char *host_to_connect, u_short port_to_connect,
1991 int gateway_ports, int remote_fwd)
1992{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001993 Channel *c;
Ben Lindstrome9c99912001-06-09 00:41:05 +00001994 int success, sock, on = 1, type;
Damien Miller34132e52000-01-14 15:45:46 +11001995 struct addrinfo hints, *ai, *aitop;
1996 char ntop[NI_MAXHOST], strport[NI_MAXSERV];
Damien Miller0bc1bd82000-11-13 22:57:25 +11001997 const char *host;
Damien Miller5428f641999-11-25 11:54:57 +11001998 struct linger linger;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001999
Kevin Steves12057502001-02-05 14:54:34 +00002000 success = 0;
2001
Damien Miller0bc1bd82000-11-13 22:57:25 +11002002 if (remote_fwd) {
2003 host = listen_address;
Ben Lindstrome9c99912001-06-09 00:41:05 +00002004 type = SSH_CHANNEL_RPORT_LISTENER;
Damien Miller0bc1bd82000-11-13 22:57:25 +11002005 } else {
2006 host = host_to_connect;
Ben Lindstrome9c99912001-06-09 00:41:05 +00002007 type = SSH_CHANNEL_PORT_LISTENER;
Damien Miller0bc1bd82000-11-13 22:57:25 +11002008 }
2009
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002010 if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) {
Kevin Steves12057502001-02-05 14:54:34 +00002011 error("Forward host name too long.");
2012 return success;
2013 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002014
Damien Miller0bc1bd82000-11-13 22:57:25 +11002015 /* XXX listen_address is currently ignored */
Damien Miller5428f641999-11-25 11:54:57 +11002016 /*
Damien Miller34132e52000-01-14 15:45:46 +11002017 * getaddrinfo returns a loopback address if the hostname is
2018 * set to NULL and hints.ai_flags is not AI_PASSIVE
Damien Miller5428f641999-11-25 11:54:57 +11002019 */
Damien Miller34132e52000-01-14 15:45:46 +11002020 memset(&hints, 0, sizeof(hints));
2021 hints.ai_family = IPv4or6;
2022 hints.ai_flags = gateway_ports ? AI_PASSIVE : 0;
2023 hints.ai_socktype = SOCK_STREAM;
Damien Miller0bc1bd82000-11-13 22:57:25 +11002024 snprintf(strport, sizeof strport, "%d", listen_port);
Damien Miller34132e52000-01-14 15:45:46 +11002025 if (getaddrinfo(NULL, strport, &hints, &aitop) != 0)
2026 packet_disconnect("getaddrinfo: fatal error");
Damien Miller5428f641999-11-25 11:54:57 +11002027
Damien Miller34132e52000-01-14 15:45:46 +11002028 for (ai = aitop; ai; ai = ai->ai_next) {
2029 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2030 continue;
2031 if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2032 strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
Damien Miller0bc1bd82000-11-13 22:57:25 +11002033 error("channel_request_forwarding: getnameinfo failed");
Damien Miller34132e52000-01-14 15:45:46 +11002034 continue;
2035 }
2036 /* Create a port to listen for the host. */
2037 sock = socket(ai->ai_family, SOCK_STREAM, 0);
2038 if (sock < 0) {
2039 /* this is no error since kernel may not support ipv6 */
2040 verbose("socket: %.100s", strerror(errno));
2041 continue;
2042 }
2043 /*
2044 * Set socket options. We would like the socket to disappear
2045 * as soon as it has been closed for whatever reason.
2046 */
2047 setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on));
2048 linger.l_onoff = 1;
2049 linger.l_linger = 5;
2050 setsockopt(sock, SOL_SOCKET, SO_LINGER, (void *)&linger, sizeof(linger));
2051 debug("Local forwarding listening on %s port %s.", ntop, strport);
Damien Miller95def091999-11-25 00:26:21 +11002052
Damien Miller34132e52000-01-14 15:45:46 +11002053 /* Bind the socket to the address. */
2054 if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2055 /* address can be in use ipv6 address is already bound */
Damien Miller3c7eeb22000-03-03 22:35:33 +11002056 if (!ai->ai_next)
2057 error("bind: %.100s", strerror(errno));
2058 else
2059 verbose("bind: %.100s", strerror(errno));
Kevin Stevesef4eea92001-02-05 12:42:17 +00002060
Damien Miller34132e52000-01-14 15:45:46 +11002061 close(sock);
2062 continue;
2063 }
2064 /* Start listening for connections on the socket. */
2065 if (listen(sock, 5) < 0) {
2066 error("listen: %.100s", strerror(errno));
2067 close(sock);
2068 continue;
2069 }
2070 /* Allocate a channel number for the socket. */
Ben Lindstrome9c99912001-06-09 00:41:05 +00002071 c = channel_new("port listener", type, sock, sock, -1,
Damien Millerbd483e72000-04-30 10:00:53 +10002072 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
Damien Miller69b69aa2000-10-28 14:19:58 +11002073 0, xstrdup("port listener"), 1);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002074 if (c == NULL) {
2075 error("channel_request_forwarding: channel_new failed");
2076 close(sock);
2077 continue;
2078 }
2079 strlcpy(c->path, host, sizeof(c->path));
2080 c->host_port = port_to_connect;
2081 c->listening_port = listen_port;
Damien Miller34132e52000-01-14 15:45:46 +11002082 success = 1;
2083 }
2084 if (success == 0)
Kevin Steves12057502001-02-05 14:54:34 +00002085 error("channel_request_forwarding: cannot listen to port: %d",
2086 listen_port);
Damien Miller34132e52000-01-14 15:45:46 +11002087 freeaddrinfo(aitop);
Kevin Steves12057502001-02-05 14:54:34 +00002088 return success;
Damien Miller95def091999-11-25 00:26:21 +11002089}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002090
Damien Miller5428f641999-11-25 11:54:57 +11002091/*
2092 * Initiate forwarding of connections to port "port" on remote host through
2093 * the secure channel to host:port from local side.
2094 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002095
Damien Miller4af51302000-04-16 11:18:38 +10002096void
Damien Miller0bc1bd82000-11-13 22:57:25 +11002097channel_request_remote_forwarding(u_short listen_port,
2098 const char *host_to_connect, u_short port_to_connect)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002099{
Damien Miller0bc1bd82000-11-13 22:57:25 +11002100 int payload_len, type, success = 0;
2101
Damien Miller95def091999-11-25 00:26:21 +11002102 /* Record locally that connection to this host/port is permitted. */
2103 if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2104 fatal("channel_request_remote_forwarding: too many forwards");
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002105
Damien Miller95def091999-11-25 00:26:21 +11002106 /* Send the forward request to the remote side. */
Damien Miller33b13562000-04-04 14:38:59 +10002107 if (compat20) {
2108 const char *address_to_bind = "0.0.0.0";
2109 packet_start(SSH2_MSG_GLOBAL_REQUEST);
2110 packet_put_cstring("tcpip-forward");
2111 packet_put_char(0); /* boolean: want reply */
2112 packet_put_cstring(address_to_bind);
2113 packet_put_int(listen_port);
Damien Miller0bc1bd82000-11-13 22:57:25 +11002114 packet_send();
2115 packet_write_wait();
2116 /* Assume that server accepts the request */
2117 success = 1;
Damien Miller33b13562000-04-04 14:38:59 +10002118 } else {
2119 packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
Damien Miller33b13562000-04-04 14:38:59 +10002120 packet_put_int(listen_port);
Damien Miller8bb73be2000-04-19 16:26:12 +10002121 packet_put_cstring(host_to_connect);
2122 packet_put_int(port_to_connect);
Damien Miller33b13562000-04-04 14:38:59 +10002123 packet_send();
2124 packet_write_wait();
Damien Miller0bc1bd82000-11-13 22:57:25 +11002125
2126 /* Wait for response from the remote side. */
2127 type = packet_read(&payload_len);
2128 switch (type) {
2129 case SSH_SMSG_SUCCESS:
2130 success = 1;
2131 break;
2132 case SSH_SMSG_FAILURE:
2133 log("Warning: Server denied remote port forwarding.");
2134 break;
2135 default:
2136 /* Unknown packet */
2137 packet_disconnect("Protocol error for port forward request:"
2138 "received packet type %d.", type);
2139 }
2140 }
2141 if (success) {
2142 permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
2143 permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
2144 permitted_opens[num_permitted_opens].listen_port = listen_port;
2145 num_permitted_opens++;
Damien Miller33b13562000-04-04 14:38:59 +10002146 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002147}
2148
Damien Miller5428f641999-11-25 11:54:57 +11002149/*
2150 * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
2151 * listening for the port, and sends back a success reply (or disconnect
2152 * message if there was an error). This never returns if there was an error.
2153 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002154
Damien Miller4af51302000-04-16 11:18:38 +10002155void
Damien Millere247cc42000-05-07 12:03:14 +10002156channel_input_port_forward_request(int is_root, int gateway_ports)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002157{
Damien Milleraae6c611999-12-06 11:47:28 +11002158 u_short port, host_port;
Damien Miller95def091999-11-25 00:26:21 +11002159 char *hostname;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002160
Damien Miller95def091999-11-25 00:26:21 +11002161 /* Get arguments from the packet. */
2162 port = packet_get_int();
2163 hostname = packet_get_string(NULL);
2164 host_port = packet_get_int();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002165
Damien Millerbac2d8a2000-09-05 16:13:06 +11002166#ifndef HAVE_CYGWIN
Damien Miller5428f641999-11-25 11:54:57 +11002167 /*
2168 * Check that an unprivileged user is not trying to forward a
2169 * privileged port.
2170 */
Damien Miller95def091999-11-25 00:26:21 +11002171 if (port < IPPORT_RESERVED && !is_root)
2172 packet_disconnect("Requested forwarding of port %d but user is not root.",
2173 port);
Damien Millerbac2d8a2000-09-05 16:13:06 +11002174#endif
Damien Miller0bc1bd82000-11-13 22:57:25 +11002175 /* Initiate forwarding */
Damien Millere247cc42000-05-07 12:03:14 +10002176 channel_request_local_forwarding(port, hostname, host_port, gateway_ports);
Damien Miller95def091999-11-25 00:26:21 +11002177
2178 /* Free the argument string. */
2179 xfree(hostname);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002180}
2181
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002182/*
2183 * Permits opening to any host/port if permitted_opens[] is empty. This is
2184 * usually called by the server, because the user could connect to any port
2185 * anyway, and the server has no way to know but to trust the client anyway.
2186 */
2187void
2188channel_permit_all_opens()
2189{
2190 if (num_permitted_opens == 0)
2191 all_opens_permitted = 1;
2192}
2193
Ben Lindstroma3700052001-04-05 23:26:32 +00002194void
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002195channel_add_permitted_opens(char *host, int port)
2196{
2197 if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2198 fatal("channel_request_remote_forwarding: too many forwards");
2199 debug("allow port forwarding to host %s port %d", host, port);
2200
2201 permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
2202 permitted_opens[num_permitted_opens].port_to_connect = port;
2203 num_permitted_opens++;
2204
2205 all_opens_permitted = 0;
2206}
2207
Ben Lindstroma3700052001-04-05 23:26:32 +00002208void
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002209channel_clear_permitted_opens(void)
2210{
2211 int i;
2212
2213 for (i = 0; i < num_permitted_opens; i++)
2214 xfree(permitted_opens[i].host_to_connect);
2215 num_permitted_opens = 0;
2216
2217}
2218
2219
2220/* return socket to remote host, port */
Ben Lindstrombba81212001-06-25 05:01:22 +00002221static int
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002222connect_to(const char *host, u_short port)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002223{
Damien Miller34132e52000-01-14 15:45:46 +11002224 struct addrinfo hints, *ai, *aitop;
2225 char ntop[NI_MAXHOST], strport[NI_MAXSERV];
2226 int gaierr;
Damien Millerb38eff82000-04-01 11:09:21 +10002227 int sock = -1;
Damien Miller95def091999-11-25 00:26:21 +11002228
Damien Miller34132e52000-01-14 15:45:46 +11002229 memset(&hints, 0, sizeof(hints));
2230 hints.ai_family = IPv4or6;
2231 hints.ai_socktype = SOCK_STREAM;
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002232 snprintf(strport, sizeof strport, "%d", port);
Damien Miller34132e52000-01-14 15:45:46 +11002233 if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) {
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002234 error("connect_to %.100s: unknown host (%s)", host,
2235 gai_strerror(gaierr));
Damien Millerb38eff82000-04-01 11:09:21 +10002236 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002237 }
Damien Miller34132e52000-01-14 15:45:46 +11002238 for (ai = aitop; ai; ai = ai->ai_next) {
2239 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2240 continue;
2241 if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2242 strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002243 error("connect_to: getnameinfo failed");
Damien Miller34132e52000-01-14 15:45:46 +11002244 continue;
2245 }
Damien Miller34132e52000-01-14 15:45:46 +11002246 sock = socket(ai->ai_family, SOCK_STREAM, 0);
2247 if (sock < 0) {
2248 error("socket: %.100s", strerror(errno));
2249 continue;
2250 }
Ben Lindstrom48bd7c12001-01-09 00:35:42 +00002251 if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0)
Ben Lindstrom7ad97102000-12-06 01:42:49 +00002252 fatal("connect_to: F_SETFL: %s", strerror(errno));
Ben Lindstrom7ad97102000-12-06 01:42:49 +00002253 if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 &&
2254 errno != EINPROGRESS) {
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002255 error("connect_to %.100s port %s: %.100s", ntop, strport,
Damien Miller34132e52000-01-14 15:45:46 +11002256 strerror(errno));
2257 close(sock);
Kevin Stevesef4eea92001-02-05 12:42:17 +00002258 continue; /* fail -- try next */
Damien Miller34132e52000-01-14 15:45:46 +11002259 }
2260 break; /* success */
2261
2262 }
2263 freeaddrinfo(aitop);
Damien Miller34132e52000-01-14 15:45:46 +11002264 if (!ai) {
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002265 error("connect_to %.100s port %d: failed.", host, port);
Damien Millerb38eff82000-04-01 11:09:21 +10002266 return -1;
2267 }
2268 /* success */
2269 return sock;
2270}
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002271
Damien Miller0bc1bd82000-11-13 22:57:25 +11002272int
2273channel_connect_by_listen_adress(u_short listen_port)
2274{
2275 int i;
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002276
Damien Miller0bc1bd82000-11-13 22:57:25 +11002277 for (i = 0; i < num_permitted_opens; i++)
2278 if (permitted_opens[i].listen_port == listen_port)
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002279 return connect_to(
Damien Miller0bc1bd82000-11-13 22:57:25 +11002280 permitted_opens[i].host_to_connect,
2281 permitted_opens[i].port_to_connect);
Ben Lindstromc72745a2000-12-02 19:03:54 +00002282 error("WARNING: Server requests forwarding for unknown listen_port %d",
2283 listen_port);
Damien Miller0bc1bd82000-11-13 22:57:25 +11002284 return -1;
2285}
Damien Millerb38eff82000-04-01 11:09:21 +10002286
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002287/* Check if connecting to that port is permitted and connect. */
2288int
2289channel_connect_to(const char *host, u_short port)
2290{
2291 int i, permit;
2292
2293 permit = all_opens_permitted;
2294 if (!permit) {
2295 for (i = 0; i < num_permitted_opens; i++)
2296 if (permitted_opens[i].port_to_connect == port &&
2297 strcmp(permitted_opens[i].host_to_connect, host) == 0)
2298 permit = 1;
2299
2300 }
2301 if (!permit) {
2302 log("Received request to connect to host %.100s port %d, "
2303 "but the request was denied.", host, port);
2304 return -1;
2305 }
2306 return connect_to(host, port);
2307}
2308
Ben Lindstrome9c99912001-06-09 00:41:05 +00002309/* -- X11 forwarding */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002310
Damien Miller5428f641999-11-25 11:54:57 +11002311/*
2312 * Creates an internet domain socket for listening for X11 connections.
2313 * Returns a suitable value for the DISPLAY variable, or NULL if an error
2314 * occurs.
2315 */
Damien Miller95def091999-11-25 00:26:21 +11002316char *
Damien Millera34a28b1999-12-14 10:47:15 +11002317x11_create_display_inet(int screen_number, int x11_display_offset)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002318{
Damien Milleraae6c611999-12-06 11:47:28 +11002319 int display_number, sock;
2320 u_short port;
Damien Miller34132e52000-01-14 15:45:46 +11002321 struct addrinfo hints, *ai, *aitop;
2322 char strport[NI_MAXSERV];
2323 int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
2324 char display[512];
Damien Miller95def091999-11-25 00:26:21 +11002325 char hostname[MAXHOSTNAMELEN];
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002326
Damien Millera34a28b1999-12-14 10:47:15 +11002327 for (display_number = x11_display_offset;
Damien Miller95def091999-11-25 00:26:21 +11002328 display_number < MAX_DISPLAYS;
2329 display_number++) {
2330 port = 6000 + display_number;
Damien Miller34132e52000-01-14 15:45:46 +11002331 memset(&hints, 0, sizeof(hints));
2332 hints.ai_family = IPv4or6;
2333 hints.ai_flags = AI_PASSIVE; /* XXX loopback only ? */
2334 hints.ai_socktype = SOCK_STREAM;
2335 snprintf(strport, sizeof strport, "%d", port);
2336 if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
2337 error("getaddrinfo: %.100s", gai_strerror(gaierr));
Damien Miller95def091999-11-25 00:26:21 +11002338 return NULL;
2339 }
Damien Miller34132e52000-01-14 15:45:46 +11002340 for (ai = aitop; ai; ai = ai->ai_next) {
2341 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2342 continue;
2343 sock = socket(ai->ai_family, SOCK_STREAM, 0);
2344 if (sock < 0) {
Damien Miller89d97962000-10-14 12:37:19 +11002345 if ((errno != EINVAL) && (errno != EAFNOSUPPORT)) {
Damien Millere2192732000-01-17 13:22:55 +11002346 error("socket: %.100s", strerror(errno));
2347 return NULL;
2348 } else {
Damien Millercb5e44a2000-09-29 12:12:36 +11002349 debug("x11_create_display_inet: Socket family %d not supported",
2350 ai->ai_family);
Damien Millere2192732000-01-17 13:22:55 +11002351 continue;
2352 }
Damien Miller34132e52000-01-14 15:45:46 +11002353 }
2354 if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2355 debug("bind port %d: %.100s", port, strerror(errno));
2356 shutdown(sock, SHUT_RDWR);
2357 close(sock);
Damien Miller3c7eeb22000-03-03 22:35:33 +11002358
2359 if (ai->ai_next)
2360 continue;
2361
Damien Miller34132e52000-01-14 15:45:46 +11002362 for (n = 0; n < num_socks; n++) {
2363 shutdown(socks[n], SHUT_RDWR);
2364 close(socks[n]);
2365 }
2366 num_socks = 0;
2367 break;
2368 }
2369 socks[num_socks++] = sock;
Damien Miller7bcb0892000-03-11 20:45:40 +11002370#ifndef DONT_TRY_OTHER_AF
Damien Miller34132e52000-01-14 15:45:46 +11002371 if (num_socks == NUM_SOCKS)
2372 break;
Damien Miller7bcb0892000-03-11 20:45:40 +11002373#else
2374 break;
2375#endif
Damien Miller95def091999-11-25 00:26:21 +11002376 }
Ben Lindstrom87b147f2001-01-25 00:41:12 +00002377 freeaddrinfo(aitop);
Damien Miller34132e52000-01-14 15:45:46 +11002378 if (num_socks > 0)
2379 break;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002380 }
Damien Miller95def091999-11-25 00:26:21 +11002381 if (display_number >= MAX_DISPLAYS) {
2382 error("Failed to allocate internet-domain X11 display socket.");
2383 return NULL;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002384 }
Damien Miller95def091999-11-25 00:26:21 +11002385 /* Start listening for connections on the socket. */
Damien Miller34132e52000-01-14 15:45:46 +11002386 for (n = 0; n < num_socks; n++) {
2387 sock = socks[n];
2388 if (listen(sock, 5) < 0) {
2389 error("listen: %.100s", strerror(errno));
2390 shutdown(sock, SHUT_RDWR);
2391 close(sock);
2392 return NULL;
2393 }
Damien Miller95def091999-11-25 00:26:21 +11002394 }
Damien Miller34132e52000-01-14 15:45:46 +11002395
Damien Miller95def091999-11-25 00:26:21 +11002396 /* Set up a suitable value for the DISPLAY variable. */
2397 if (gethostname(hostname, sizeof(hostname)) < 0)
2398 fatal("gethostname: %.100s", strerror(errno));
Damien Miller76112de1999-12-21 11:18:08 +11002399
2400#ifdef IPADDR_IN_DISPLAY
Kevin Stevesef4eea92001-02-05 12:42:17 +00002401 /*
Damien Miller76112de1999-12-21 11:18:08 +11002402 * HPUX detects the local hostname in the DISPLAY variable and tries
2403 * to set up a shared memory connection to the server, which it
2404 * incorrectly supposes to be local.
2405 *
2406 * The workaround - as used in later $$H and other programs - is
2407 * is to set display to the host's IP address.
2408 */
2409 {
2410 struct hostent *he;
2411 struct in_addr my_addr;
2412
2413 he = gethostbyname(hostname);
2414 if (he == NULL) {
2415 error("[X11-broken-fwd-hostname-workaround] Could not get "
2416 "IP address for hostname %s.", hostname);
2417
2418 packet_send_debug("[X11-broken-fwd-hostname-workaround]"
2419 "Could not get IP address for hostname %s.", hostname);
2420
2421 shutdown(sock, SHUT_RDWR);
2422 close(sock);
2423
2424 return NULL;
2425 }
2426
2427 memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr));
2428
2429 /* Set DISPLAY to <ip address>:screen.display */
Kevin Stevesef4eea92001-02-05 12:42:17 +00002430 snprintf(display, sizeof(display), "%.50s:%d.%d", inet_ntoa(my_addr),
Kevin Stevesda6cd592000-12-29 18:41:21 +00002431 display_number, screen_number);
Damien Miller76112de1999-12-21 11:18:08 +11002432 }
2433#else /* IPADDR_IN_DISPLAY */
2434 /* Just set DISPLAY to hostname:screen.display */
Damien Miller34132e52000-01-14 15:45:46 +11002435 snprintf(display, sizeof display, "%.400s:%d.%d", hostname,
Kevin Stevesda6cd592000-12-29 18:41:21 +00002436 display_number, screen_number);
Damien Miller76112de1999-12-21 11:18:08 +11002437#endif /* IPADDR_IN_DISPLAY */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002438
Damien Miller34132e52000-01-14 15:45:46 +11002439 /* Allocate a channel for each socket. */
2440 for (n = 0; n < num_socks; n++) {
2441 sock = socks[n];
Damien Millerbd483e72000-04-30 10:00:53 +10002442 (void) channel_new("x11 listener",
2443 SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
2444 CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
Damien Miller69b69aa2000-10-28 14:19:58 +11002445 0, xstrdup("X11 inet listener"), 1);
Damien Miller34132e52000-01-14 15:45:46 +11002446 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002447
Damien Miller95def091999-11-25 00:26:21 +11002448 /* Return a suitable value for the DISPLAY environment variable. */
Damien Miller34132e52000-01-14 15:45:46 +11002449 return xstrdup(display);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002450}
2451
2452#ifndef X_UNIX_PATH
2453#define X_UNIX_PATH "/tmp/.X11-unix/X"
2454#endif
2455
Ben Lindstrombba81212001-06-25 05:01:22 +00002456static int
Ben Lindstrom46c16222000-12-22 01:43:59 +00002457connect_local_xsocket(u_int dnr)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002458{
Damien Miller95def091999-11-25 00:26:21 +11002459 static const char *const x_sockets[] = {
2460 X_UNIX_PATH "%u",
2461 "/var/X/.X11-unix/X" "%u",
2462 "/usr/spool/sockets/X11/" "%u",
2463 NULL
2464 };
2465 int sock;
2466 struct sockaddr_un addr;
2467 const char *const * path;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002468
Damien Miller95def091999-11-25 00:26:21 +11002469 for (path = x_sockets; *path; ++path) {
2470 sock = socket(AF_UNIX, SOCK_STREAM, 0);
2471 if (sock < 0)
2472 error("socket: %.100s", strerror(errno));
2473 memset(&addr, 0, sizeof(addr));
2474 addr.sun_family = AF_UNIX;
2475 snprintf(addr.sun_path, sizeof addr.sun_path, *path, dnr);
2476 if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0)
2477 return sock;
2478 close(sock);
2479 }
2480 error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
2481 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002482}
2483
Damien Millerbd483e72000-04-30 10:00:53 +10002484int
2485x11_connect_display(void)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002486{
Damien Millerbd483e72000-04-30 10:00:53 +10002487 int display_number, sock = 0;
Damien Miller95def091999-11-25 00:26:21 +11002488 const char *display;
Damien Millerbd483e72000-04-30 10:00:53 +10002489 char buf[1024], *cp;
Damien Miller34132e52000-01-14 15:45:46 +11002490 struct addrinfo hints, *ai, *aitop;
2491 char strport[NI_MAXSERV];
2492 int gaierr;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002493
Damien Miller95def091999-11-25 00:26:21 +11002494 /* Try to open a socket for the local X server. */
2495 display = getenv("DISPLAY");
2496 if (!display) {
2497 error("DISPLAY not set.");
Damien Millerbd483e72000-04-30 10:00:53 +10002498 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002499 }
Damien Miller5428f641999-11-25 11:54:57 +11002500 /*
2501 * Now we decode the value of the DISPLAY variable and make a
2502 * connection to the real X server.
2503 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002504
Damien Miller5428f641999-11-25 11:54:57 +11002505 /*
2506 * Check if it is a unix domain socket. Unix domain displays are in
2507 * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
2508 */
Damien Miller95def091999-11-25 00:26:21 +11002509 if (strncmp(display, "unix:", 5) == 0 ||
2510 display[0] == ':') {
2511 /* Connect to the unix domain socket. */
2512 if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) {
2513 error("Could not parse display number from DISPLAY: %.100s",
2514 display);
Damien Millerbd483e72000-04-30 10:00:53 +10002515 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002516 }
2517 /* Create a socket. */
2518 sock = connect_local_xsocket(display_number);
2519 if (sock < 0)
Damien Millerbd483e72000-04-30 10:00:53 +10002520 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002521
2522 /* OK, we now have a connection to the display. */
Damien Millerbd483e72000-04-30 10:00:53 +10002523 return sock;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002524 }
Damien Miller5428f641999-11-25 11:54:57 +11002525 /*
2526 * Connect to an inet socket. The DISPLAY value is supposedly
2527 * hostname:d[.s], where hostname may also be numeric IP address.
2528 */
Damien Miller95def091999-11-25 00:26:21 +11002529 strncpy(buf, display, sizeof(buf));
2530 buf[sizeof(buf) - 1] = 0;
2531 cp = strchr(buf, ':');
2532 if (!cp) {
2533 error("Could not find ':' in DISPLAY: %.100s", display);
Damien Millerbd483e72000-04-30 10:00:53 +10002534 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002535 }
Damien Miller95def091999-11-25 00:26:21 +11002536 *cp = 0;
Damien Miller5428f641999-11-25 11:54:57 +11002537 /* buf now contains the host name. But first we parse the display number. */
Damien Miller95def091999-11-25 00:26:21 +11002538 if (sscanf(cp + 1, "%d", &display_number) != 1) {
2539 error("Could not parse display number from DISPLAY: %.100s",
2540 display);
Damien Millerbd483e72000-04-30 10:00:53 +10002541 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002542 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002543
Damien Miller34132e52000-01-14 15:45:46 +11002544 /* Look up the host address */
2545 memset(&hints, 0, sizeof(hints));
2546 hints.ai_family = IPv4or6;
2547 hints.ai_socktype = SOCK_STREAM;
2548 snprintf(strport, sizeof strport, "%d", 6000 + display_number);
2549 if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
2550 error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr));
Damien Millerbd483e72000-04-30 10:00:53 +10002551 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002552 }
Damien Miller34132e52000-01-14 15:45:46 +11002553 for (ai = aitop; ai; ai = ai->ai_next) {
2554 /* Create a socket. */
2555 sock = socket(ai->ai_family, SOCK_STREAM, 0);
2556 if (sock < 0) {
2557 debug("socket: %.100s", strerror(errno));
Damien Millerb38eff82000-04-01 11:09:21 +10002558 continue;
2559 }
2560 /* Connect it to the display. */
2561 if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2562 debug("connect %.100s port %d: %.100s", buf,
2563 6000 + display_number, strerror(errno));
2564 close(sock);
2565 continue;
2566 }
2567 /* Success */
2568 break;
Damien Miller34132e52000-01-14 15:45:46 +11002569 }
Damien Miller34132e52000-01-14 15:45:46 +11002570 freeaddrinfo(aitop);
2571 if (!ai) {
Damien Miller4af51302000-04-16 11:18:38 +10002572 error("connect %.100s port %d: %.100s", buf, 6000 + display_number,
Damien Miller34132e52000-01-14 15:45:46 +11002573 strerror(errno));
Damien Millerbd483e72000-04-30 10:00:53 +10002574 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002575 }
Damien Millerbd483e72000-04-30 10:00:53 +10002576 return sock;
2577}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002578
Damien Millerbd483e72000-04-30 10:00:53 +10002579/*
2580 * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
2581 * the remote channel number. We should do whatever we want, and respond
2582 * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
2583 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002584
Damien Millerbd483e72000-04-30 10:00:53 +10002585void
Damien Miller62cee002000-09-23 17:15:56 +11002586x11_input_open(int type, int plen, void *ctxt)
Damien Millerbd483e72000-04-30 10:00:53 +10002587{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002588 Channel *c = NULL;
2589 int remote_id, sock = 0;
Damien Millerbd483e72000-04-30 10:00:53 +10002590 char *remote_host;
Damien Millerbd483e72000-04-30 10:00:53 +10002591
2592 debug("Received X11 open request.");
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002593
2594 remote_id = packet_get_int();
Ben Lindstrome9c99912001-06-09 00:41:05 +00002595
2596 if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002597 remote_host = packet_get_string(NULL);
2598 } else {
2599 remote_host = xstrdup("unknown (remote did not supply name)");
2600 }
2601 packet_done();
Damien Millerbd483e72000-04-30 10:00:53 +10002602
2603 /* Obtain a connection to the real X display. */
2604 sock = x11_connect_display();
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002605 if (sock != -1) {
2606 /* Allocate a channel for this connection. */
2607 c = channel_new("connected x11 socket",
2608 SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
2609 remote_host, 1);
2610 if (c == NULL) {
2611 error("x11_input_open: channel_new failed");
2612 close(sock);
2613 } else {
2614 c->remote_id = remote_id;
2615 }
2616 }
2617 if (c == NULL) {
Damien Millerbd483e72000-04-30 10:00:53 +10002618 /* Send refusal to the remote host. */
2619 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002620 packet_put_int(remote_id);
Damien Millerbd483e72000-04-30 10:00:53 +10002621 } else {
Damien Millerbd483e72000-04-30 10:00:53 +10002622 /* Send a confirmation to the remote host. */
2623 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002624 packet_put_int(remote_id);
2625 packet_put_int(c->self);
Damien Millerbd483e72000-04-30 10:00:53 +10002626 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002627 packet_send();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002628}
2629
Damien Miller69b69aa2000-10-28 14:19:58 +11002630/* dummy protocol handler that denies SSH-1 requests (agent/x11) */
2631void
2632deny_input_open(int type, int plen, void *ctxt)
2633{
2634 int rchan = packet_get_int();
2635 switch(type){
2636 case SSH_SMSG_AGENT_OPEN:
2637 error("Warning: ssh server tried agent forwarding.");
2638 break;
2639 case SSH_SMSG_X11_OPEN:
2640 error("Warning: ssh server tried X11 forwarding.");
2641 break;
2642 default:
2643 error("deny_input_open: type %d plen %d", type, plen);
2644 break;
2645 }
2646 error("Warning: this is probably a break in attempt by a malicious server.");
2647 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2648 packet_put_int(rchan);
2649 packet_send();
2650}
2651
Damien Miller5428f641999-11-25 11:54:57 +11002652/*
2653 * Requests forwarding of X11 connections, generates fake authentication
2654 * data, and enables authentication spoofing.
Ben Lindstrome9c99912001-06-09 00:41:05 +00002655 * This should be called in the client only.
Damien Miller5428f641999-11-25 11:54:57 +11002656 */
Damien Miller4af51302000-04-16 11:18:38 +10002657void
Damien Millerbd483e72000-04-30 10:00:53 +10002658x11_request_forwarding_with_spoofing(int client_session_id,
2659 const char *proto, const char *data)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002660{
Ben Lindstrom46c16222000-12-22 01:43:59 +00002661 u_int data_len = (u_int) strlen(data) / 2;
Ben Lindstromb3211a82001-02-10 22:33:19 +00002662 u_int i, value, len;
Damien Miller95def091999-11-25 00:26:21 +11002663 char *new_data;
2664 int screen_number;
2665 const char *cp;
2666 u_int32_t rand = 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002667
Damien Miller95def091999-11-25 00:26:21 +11002668 cp = getenv("DISPLAY");
2669 if (cp)
2670 cp = strchr(cp, ':');
2671 if (cp)
2672 cp = strchr(cp, '.');
2673 if (cp)
2674 screen_number = atoi(cp + 1);
2675 else
2676 screen_number = 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002677
Damien Miller95def091999-11-25 00:26:21 +11002678 /* Save protocol name. */
2679 x11_saved_proto = xstrdup(proto);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002680
Damien Miller5428f641999-11-25 11:54:57 +11002681 /*
2682 * Extract real authentication data and generate fake data of the
2683 * same length.
2684 */
Damien Miller95def091999-11-25 00:26:21 +11002685 x11_saved_data = xmalloc(data_len);
2686 x11_fake_data = xmalloc(data_len);
2687 for (i = 0; i < data_len; i++) {
2688 if (sscanf(data + 2 * i, "%2x", &value) != 1)
2689 fatal("x11_request_forwarding: bad authentication data: %.100s", data);
2690 if (i % 4 == 0)
2691 rand = arc4random();
2692 x11_saved_data[i] = value;
2693 x11_fake_data[i] = rand & 0xff;
2694 rand >>= 8;
2695 }
2696 x11_saved_data_len = data_len;
2697 x11_fake_data_len = data_len;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002698
Damien Miller95def091999-11-25 00:26:21 +11002699 /* Convert the fake data into hex. */
Ben Lindstromb3211a82001-02-10 22:33:19 +00002700 len = 2 * data_len + 1;
2701 new_data = xmalloc(len);
Damien Miller95def091999-11-25 00:26:21 +11002702 for (i = 0; i < data_len; i++)
Ben Lindstromb3211a82001-02-10 22:33:19 +00002703 snprintf(new_data + 2 * i, len - 2 * i,
2704 "%02x", (u_char) x11_fake_data[i]);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002705
Damien Miller95def091999-11-25 00:26:21 +11002706 /* Send the request packet. */
Damien Millerbd483e72000-04-30 10:00:53 +10002707 if (compat20) {
2708 channel_request_start(client_session_id, "x11-req", 0);
2709 packet_put_char(0); /* XXX bool single connection */
2710 } else {
2711 packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
2712 }
2713 packet_put_cstring(proto);
2714 packet_put_cstring(new_data);
Damien Miller95def091999-11-25 00:26:21 +11002715 packet_put_int(screen_number);
2716 packet_send();
2717 packet_write_wait();
2718 xfree(new_data);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002719}
2720
Ben Lindstrome9c99912001-06-09 00:41:05 +00002721
2722/* -- agent forwarding */
2723
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002724/* Sends a message to the server to request authentication fd forwarding. */
2725
Damien Miller4af51302000-04-16 11:18:38 +10002726void
Damien Miller95def091999-11-25 00:26:21 +11002727auth_request_forwarding()
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002728{
Damien Miller95def091999-11-25 00:26:21 +11002729 packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
2730 packet_send();
2731 packet_write_wait();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002732}
2733
Damien Miller5428f641999-11-25 11:54:57 +11002734/*
2735 * Returns the name of the forwarded authentication socket. Returns NULL if
2736 * there is no forwarded authentication socket. The returned value points to
2737 * a static buffer.
2738 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002739
Damien Miller95def091999-11-25 00:26:21 +11002740char *
2741auth_get_socket_name()
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002742{
Ben Lindstrome9c99912001-06-09 00:41:05 +00002743 return auth_sock_name;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002744}
2745
2746/* removes the agent forwarding socket */
2747
Damien Miller4af51302000-04-16 11:18:38 +10002748void
Ben Lindstrom983c0982001-06-09 01:20:06 +00002749auth_sock_cleanup_proc(void *_pw)
Damien Miller95def091999-11-25 00:26:21 +11002750{
Ben Lindstrom983c0982001-06-09 01:20:06 +00002751 struct passwd *pw = _pw;
2752
Ben Lindstrom838394c2001-06-09 01:11:59 +00002753 if (auth_sock_name) {
Ben Lindstrom983c0982001-06-09 01:20:06 +00002754 temporarily_use_uid(pw);
Ben Lindstrom838394c2001-06-09 01:11:59 +00002755 unlink(auth_sock_name);
2756 rmdir(auth_sock_dir);
2757 auth_sock_name = NULL;
Ben Lindstrom983c0982001-06-09 01:20:06 +00002758 restore_uid();
Ben Lindstrom838394c2001-06-09 01:11:59 +00002759 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002760}
2761
Damien Miller5428f641999-11-25 11:54:57 +11002762/*
Damien Millerd3a18572000-06-07 19:55:44 +10002763 * This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server.
Damien Miller5428f641999-11-25 11:54:57 +11002764 * This starts forwarding authentication requests.
2765 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002766
Damien Millerd3a18572000-06-07 19:55:44 +10002767int
Damien Miller95def091999-11-25 00:26:21 +11002768auth_input_request_forwarding(struct passwd * pw)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002769{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002770 Channel *nc;
2771 int sock;
Damien Miller95def091999-11-25 00:26:21 +11002772 struct sockaddr_un sunaddr;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002773
Ben Lindstrome9c99912001-06-09 00:41:05 +00002774 if (auth_get_socket_name() != NULL) {
2775 error("authentication forwarding requested twice.");
2776 return 0;
2777 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002778
Damien Miller95def091999-11-25 00:26:21 +11002779 /* Temporarily drop privileged uid for mkdir/bind. */
Ben Lindstrom3fcf1a22001-04-08 18:26:59 +00002780 temporarily_use_uid(pw);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002781
Damien Miller95def091999-11-25 00:26:21 +11002782 /* Allocate a buffer for the socket name, and format the name. */
Ben Lindstrome9c99912001-06-09 00:41:05 +00002783 auth_sock_name = xmalloc(MAXPATHLEN);
2784 auth_sock_dir = xmalloc(MAXPATHLEN);
2785 strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXX", MAXPATHLEN);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002786
Damien Miller95def091999-11-25 00:26:21 +11002787 /* Create private directory for socket */
Ben Lindstrome9c99912001-06-09 00:41:05 +00002788 if (mkdtemp(auth_sock_dir) == NULL) {
2789 packet_send_debug("Agent forwarding disabled: "
2790 "mkdtemp() failed: %.100s", strerror(errno));
Damien Millerd3a18572000-06-07 19:55:44 +10002791 restore_uid();
Ben Lindstrome9c99912001-06-09 00:41:05 +00002792 xfree(auth_sock_name);
2793 xfree(auth_sock_dir);
2794 auth_sock_name = NULL;
2795 auth_sock_dir = NULL;
Damien Millerd3a18572000-06-07 19:55:44 +10002796 return 0;
2797 }
Ben Lindstrome9c99912001-06-09 00:41:05 +00002798 snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%d",
2799 auth_sock_dir, (int) getpid());
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002800
Ben Lindstrom838394c2001-06-09 01:11:59 +00002801 /* delete agent socket on fatal() */
Ben Lindstrom983c0982001-06-09 01:20:06 +00002802 fatal_add_cleanup(auth_sock_cleanup_proc, pw);
Ben Lindstrom838394c2001-06-09 01:11:59 +00002803
Damien Miller95def091999-11-25 00:26:21 +11002804 /* Create the socket. */
2805 sock = socket(AF_UNIX, SOCK_STREAM, 0);
2806 if (sock < 0)
2807 packet_disconnect("socket: %.100s", strerror(errno));
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002808
Damien Miller95def091999-11-25 00:26:21 +11002809 /* Bind it to the name. */
2810 memset(&sunaddr, 0, sizeof(sunaddr));
2811 sunaddr.sun_family = AF_UNIX;
Ben Lindstrome9c99912001-06-09 00:41:05 +00002812 strncpy(sunaddr.sun_path, auth_sock_name,
Damien Miller95def091999-11-25 00:26:21 +11002813 sizeof(sunaddr.sun_path));
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002814
Damien Miller95def091999-11-25 00:26:21 +11002815 if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0)
2816 packet_disconnect("bind: %.100s", strerror(errno));
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002817
Damien Miller95def091999-11-25 00:26:21 +11002818 /* Restore the privileged uid. */
2819 restore_uid();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002820
Damien Miller95def091999-11-25 00:26:21 +11002821 /* Start listening on the socket. */
2822 if (listen(sock, 5) < 0)
2823 packet_disconnect("listen: %.100s", strerror(errno));
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002824
Damien Miller95def091999-11-25 00:26:21 +11002825 /* Allocate a channel for the authentication agent socket. */
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002826 nc = channel_new("auth socket",
Damien Miller0bc1bd82000-11-13 22:57:25 +11002827 SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1,
2828 CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
2829 0, xstrdup("auth socket"), 1);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002830 if (nc == NULL) {
2831 error("auth_input_request_forwarding: channel_new failed");
Ben Lindstrom983c0982001-06-09 01:20:06 +00002832 auth_sock_cleanup_proc(pw);
Ben Lindstromdf4981b2001-06-09 01:32:29 +00002833 fatal_remove_cleanup(auth_sock_cleanup_proc, pw);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002834 close(sock);
2835 return 0;
2836 }
Ben Lindstrome9c99912001-06-09 00:41:05 +00002837 strlcpy(nc->path, auth_sock_name, sizeof(nc->path));
Damien Millerd3a18572000-06-07 19:55:44 +10002838 return 1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002839}
2840
2841/* This is called to process an SSH_SMSG_AGENT_OPEN message. */
2842
Damien Miller4af51302000-04-16 11:18:38 +10002843void
Damien Miller62cee002000-09-23 17:15:56 +11002844auth_input_open_request(int type, int plen, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002845{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002846 Channel *c = NULL;
2847 int remote_id, sock;
Ben Lindstrome9c99912001-06-09 00:41:05 +00002848 char *name;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002849
Damien Millerb38eff82000-04-01 11:09:21 +10002850 packet_integrity_check(plen, 4, type);
2851
Damien Miller95def091999-11-25 00:26:21 +11002852 /* Read the remote channel number from the message. */
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002853 remote_id = packet_get_int();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002854
Damien Miller5428f641999-11-25 11:54:57 +11002855 /*
2856 * Get a connection to the local authentication agent (this may again
2857 * get forwarded).
2858 */
Damien Miller95def091999-11-25 00:26:21 +11002859 sock = ssh_get_authentication_socket();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002860
Damien Miller5428f641999-11-25 11:54:57 +11002861 /*
2862 * If we could not connect the agent, send an error message back to
2863 * the server. This should never happen unless the agent dies,
2864 * because authentication forwarding is only enabled if we have an
2865 * agent.
2866 */
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002867 if (sock >= 0) {
Ben Lindstrome9c99912001-06-09 00:41:05 +00002868 name = xstrdup("authentication agent connection");
2869 c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
2870 -1, 0, 0, 0, name, 1);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002871 if (c == NULL) {
2872 error("auth_input_open_request: channel_new failed");
Ben Lindstrome9c99912001-06-09 00:41:05 +00002873 xfree(name);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002874 close(sock);
2875 } else {
2876 c->remote_id = remote_id;
2877 }
Damien Miller95def091999-11-25 00:26:21 +11002878 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002879 if (c == NULL) {
2880 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2881 packet_put_int(remote_id);
2882 } else {
2883 /* Send a confirmation to the remote host. */
2884 debug("Forwarding authentication connection.");
2885 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
2886 packet_put_int(remote_id);
2887 packet_put_int(c->self);
2888 }
Damien Miller95def091999-11-25 00:26:21 +11002889 packet_send();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002890}