blob: 7bf127d91571c59bae4da3e6f5e9068e208c5c58 [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 Lindstrom16d29d52001-07-18 16:01:46 +000042RCSID("$OpenBSD: channels.c,v 1.132 2001/07/17 21:04:56 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;
Ben Lindstrom809744e2001-07-04 05:26:06 +0000263 c->detach_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
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000269static int
270channel_find_maxfd(void)
271{
272 int i, max = 0;
273 Channel *c;
274
275 for (i = 0; i < channels_alloc; i++) {
276 c = channels[i];
277 if (c != NULL) {
278 max = MAX(max, c->rfd);
279 max = MAX(max, c->wfd);
280 max = MAX(max, c->efd);
281 }
282 }
283 return max;
284}
285
286int
287channel_close_fd(int *fdp)
288{
289 int ret = 0, fd = *fdp;
290
291 if (fd != -1) {
292 ret = close(fd);
293 *fdp = -1;
294 if (fd == channel_max_fd)
295 channel_max_fd = channel_find_maxfd();
296 }
297 return ret;
298}
299
Damien Miller6f83b8e2000-05-02 09:23:45 +1000300/* Close all channel fd/socket. */
301
Ben Lindstrombba81212001-06-25 05:01:22 +0000302static void
Damien Miller6f83b8e2000-05-02 09:23:45 +1000303channel_close_fds(Channel *c)
304{
Ben Lindstromc0dee1a2001-06-05 20:52:50 +0000305 debug3("channel_close_fds: channel %d: r %d w %d e %d",
306 c->self, c->rfd, c->wfd, c->efd);
307
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000308 channel_close_fd(&c->sock);
309 channel_close_fd(&c->rfd);
310 channel_close_fd(&c->wfd);
311 channel_close_fd(&c->efd);
Damien Miller6f83b8e2000-05-02 09:23:45 +1000312}
313
314/* Free the channel and close its fd/socket. */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000315
Damien Miller4af51302000-04-16 11:18:38 +1000316void
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000317channel_free(Channel *c)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000318{
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000319 char *s;
Ben Lindstromc0dee1a2001-06-05 20:52:50 +0000320 int i, n;
321
322 for (n = 0, i = 0; i < channels_alloc; i++)
323 if (channels[i])
324 n++;
Ben Lindstrom4c247552001-06-05 20:56:47 +0000325 debug("channel_free: channel %d: %s, nchannels %d", c->self,
Ben Lindstromc0dee1a2001-06-05 20:52:50 +0000326 c->remote_name ? c->remote_name : "???", n);
Ben Lindstrom6c3ae2b2000-12-30 03:25:14 +0000327
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000328 s = channel_open_message();
Ben Lindstrom4c247552001-06-05 20:56:47 +0000329 debug3("channel_free: status: %s", s);
Ben Lindstrom6c3ae2b2000-12-30 03:25:14 +0000330 xfree(s);
331
Ben Lindstrom809744e2001-07-04 05:26:06 +0000332 if (c->detach_user != NULL) {
333 debug("channel_free: channel %d: detaching channel user", c->self);
334 c->detach_user(c->self, NULL);
Damien Miller33b13562000-04-04 14:38:59 +1000335 }
Damien Miller6f83b8e2000-05-02 09:23:45 +1000336 if (c->sock != -1)
Damien Millerb38eff82000-04-01 11:09:21 +1000337 shutdown(c->sock, SHUT_RDWR);
Damien Miller6f83b8e2000-05-02 09:23:45 +1000338 channel_close_fds(c);
Damien Millerb38eff82000-04-01 11:09:21 +1000339 buffer_free(&c->input);
340 buffer_free(&c->output);
341 buffer_free(&c->extended);
Damien Millerb38eff82000-04-01 11:09:21 +1000342 if (c->remote_name) {
343 xfree(c->remote_name);
344 c->remote_name = NULL;
Damien Miller95def091999-11-25 00:26:21 +1100345 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000346 channels[c->self] = NULL;
347 xfree(c);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000348}
349
Ben Lindstrome9c99912001-06-09 00:41:05 +0000350void
Ben Lindstrom601e4362001-06-21 03:19:23 +0000351channel_free_all(void)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000352{
353 int i;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000354
Ben Lindstrom601e4362001-06-21 03:19:23 +0000355 for (i = 0; i < channels_alloc; i++)
356 if (channels[i] != NULL)
357 channel_free(channels[i]);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000358}
359
Ben Lindstrom809744e2001-07-04 05:26:06 +0000360void
361channel_detach_all(void)
362{
363 int i;
364 Channel *c;
365
366 for (i = 0; i < channels_alloc; i++) {
367 c = channels[i];
368 if (c != NULL && c->detach_user != NULL) {
369 debug("channel_detach_all: channel %d", c->self);
370 c->detach_user(c->self, NULL);
371 c->detach_user = NULL;
372 }
373 }
374}
375
Ben Lindstrome9c99912001-06-09 00:41:05 +0000376/*
377 * Closes the sockets/fds of all channels. This is used to close extra file
378 * descriptors after a fork.
379 */
380
381void
382channel_close_all()
383{
384 int i;
385
386 for (i = 0; i < channels_alloc; i++)
387 if (channels[i] != NULL)
388 channel_close_fds(channels[i]);
389}
390
391/*
Ben Lindstrom809744e2001-07-04 05:26:06 +0000392 * Stop listening to channels.
393 */
394
395void
396channel_stop_listening(void)
397{
398 int i;
399 Channel *c;
400
401 for (i = 0; i < channels_alloc; i++) {
402 c = channels[i];
403 if (c != NULL) {
404 switch (c->type) {
405 case SSH_CHANNEL_AUTH_SOCKET:
406 case SSH_CHANNEL_PORT_LISTENER:
407 case SSH_CHANNEL_RPORT_LISTENER:
408 case SSH_CHANNEL_X11_LISTENER:
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000409 channel_close_fd(&c->sock);
Ben Lindstrom809744e2001-07-04 05:26:06 +0000410 channel_free(c);
411 break;
412 }
413 }
414 }
415}
416
417/*
Ben Lindstrome9c99912001-06-09 00:41:05 +0000418 * Returns true if no channel has too much buffered data, and false if one or
419 * more channel is overfull.
420 */
421
422int
423channel_not_very_much_buffered_data()
424{
425 u_int i;
426 Channel *c;
427
428 for (i = 0; i < channels_alloc; i++) {
429 c = channels[i];
430 if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
431 if (!compat20 && buffer_len(&c->input) > packet_get_maxsize()) {
432 debug("channel %d: big input buffer %d",
433 c->self, buffer_len(&c->input));
434 return 0;
435 }
436 if (buffer_len(&c->output) > packet_get_maxsize()) {
437 debug("channel %d: big output buffer %d",
438 c->self, buffer_len(&c->output));
439 return 0;
440 }
441 }
442 }
443 return 1;
444}
445
446/* Returns true if any channel is still open. */
447
448int
449channel_still_open()
450{
451 int i;
452 Channel *c;
453
454 for (i = 0; i < channels_alloc; i++) {
455 c = channels[i];
456 if (c == NULL)
457 continue;
458 switch (c->type) {
459 case SSH_CHANNEL_X11_LISTENER:
460 case SSH_CHANNEL_PORT_LISTENER:
461 case SSH_CHANNEL_RPORT_LISTENER:
462 case SSH_CHANNEL_CLOSED:
463 case SSH_CHANNEL_AUTH_SOCKET:
464 case SSH_CHANNEL_DYNAMIC:
465 case SSH_CHANNEL_CONNECTING:
466 case SSH_CHANNEL_ZOMBIE:
467 continue;
468 case SSH_CHANNEL_LARVAL:
469 if (!compat20)
470 fatal("cannot happen: SSH_CHANNEL_LARVAL");
471 continue;
472 case SSH_CHANNEL_OPENING:
473 case SSH_CHANNEL_OPEN:
474 case SSH_CHANNEL_X11_OPEN:
475 return 1;
476 case SSH_CHANNEL_INPUT_DRAINING:
477 case SSH_CHANNEL_OUTPUT_DRAINING:
478 if (!compat13)
479 fatal("cannot happen: OUT_DRAIN");
480 return 1;
481 default:
482 fatal("channel_still_open: bad channel type %d", c->type);
483 /* NOTREACHED */
484 }
485 }
486 return 0;
487}
488
489/* Returns the id of an open channel suitable for keepaliving */
490
491int
492channel_find_open()
493{
494 int i;
495 Channel *c;
496
497 for (i = 0; i < channels_alloc; i++) {
498 c = channels[i];
499 if (c == NULL)
500 continue;
501 switch (c->type) {
502 case SSH_CHANNEL_CLOSED:
503 case SSH_CHANNEL_DYNAMIC:
504 case SSH_CHANNEL_X11_LISTENER:
505 case SSH_CHANNEL_PORT_LISTENER:
506 case SSH_CHANNEL_RPORT_LISTENER:
507 case SSH_CHANNEL_OPENING:
508 case SSH_CHANNEL_CONNECTING:
509 case SSH_CHANNEL_ZOMBIE:
510 continue;
511 case SSH_CHANNEL_LARVAL:
512 case SSH_CHANNEL_AUTH_SOCKET:
513 case SSH_CHANNEL_OPEN:
514 case SSH_CHANNEL_X11_OPEN:
515 return i;
516 case SSH_CHANNEL_INPUT_DRAINING:
517 case SSH_CHANNEL_OUTPUT_DRAINING:
518 if (!compat13)
519 fatal("cannot happen: OUT_DRAIN");
520 return i;
521 default:
522 fatal("channel_find_open: bad channel type %d", c->type);
523 /* NOTREACHED */
524 }
525 }
526 return -1;
527}
528
529
530/*
531 * Returns a message describing the currently open forwarded connections,
532 * suitable for sending to the client. The message contains crlf pairs for
533 * newlines.
534 */
535
536char *
537channel_open_message()
538{
539 Buffer buffer;
540 Channel *c;
541 char buf[1024], *cp;
542 int i;
543
544 buffer_init(&buffer);
545 snprintf(buf, sizeof buf, "The following connections are open:\r\n");
546 buffer_append(&buffer, buf, strlen(buf));
547 for (i = 0; i < channels_alloc; i++) {
548 c = channels[i];
549 if (c == NULL)
550 continue;
551 switch (c->type) {
552 case SSH_CHANNEL_X11_LISTENER:
553 case SSH_CHANNEL_PORT_LISTENER:
554 case SSH_CHANNEL_RPORT_LISTENER:
555 case SSH_CHANNEL_CLOSED:
556 case SSH_CHANNEL_AUTH_SOCKET:
557 case SSH_CHANNEL_ZOMBIE:
558 continue;
559 case SSH_CHANNEL_LARVAL:
560 case SSH_CHANNEL_OPENING:
561 case SSH_CHANNEL_CONNECTING:
562 case SSH_CHANNEL_DYNAMIC:
563 case SSH_CHANNEL_OPEN:
564 case SSH_CHANNEL_X11_OPEN:
565 case SSH_CHANNEL_INPUT_DRAINING:
566 case SSH_CHANNEL_OUTPUT_DRAINING:
567 snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n",
568 c->self, c->remote_name,
569 c->type, c->remote_id,
570 c->istate, buffer_len(&c->input),
571 c->ostate, buffer_len(&c->output),
572 c->rfd, c->wfd);
573 buffer_append(&buffer, buf, strlen(buf));
574 continue;
575 default:
576 fatal("channel_open_message: bad channel type %d", c->type);
577 /* NOTREACHED */
578 }
579 }
580 buffer_append(&buffer, "\0", 1);
581 cp = xstrdup(buffer_ptr(&buffer));
582 buffer_free(&buffer);
583 return cp;
584}
585
586void
587channel_send_open(int id)
588{
589 Channel *c = channel_lookup(id);
590 if (c == NULL) {
591 log("channel_send_open: %d: bad id", id);
592 return;
593 }
594 debug("send channel open %d", id);
595 packet_start(SSH2_MSG_CHANNEL_OPEN);
596 packet_put_cstring(c->ctype);
597 packet_put_int(c->self);
598 packet_put_int(c->local_window);
599 packet_put_int(c->local_maxpacket);
600 packet_send();
601}
602
603void
604channel_request(int id, char *service, int wantconfirm)
605{
606 channel_request_start(id, service, wantconfirm);
607 packet_send();
608 debug("channel request %d: %s", id, service) ;
609}
610void
611channel_request_start(int id, char *service, int wantconfirm)
612{
613 Channel *c = channel_lookup(id);
614 if (c == NULL) {
615 log("channel_request: %d: bad id", id);
616 return;
617 }
618 packet_start(SSH2_MSG_CHANNEL_REQUEST);
619 packet_put_int(c->remote_id);
620 packet_put_cstring(service);
621 packet_put_char(wantconfirm);
622}
623void
624channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg)
625{
626 Channel *c = channel_lookup(id);
627 if (c == NULL) {
628 log("channel_register_callback: %d: bad id", id);
629 return;
630 }
631 c->cb_event = mtype;
632 c->cb_fn = fn;
633 c->cb_arg = arg;
634}
635void
636channel_register_cleanup(int id, channel_callback_fn *fn)
637{
638 Channel *c = channel_lookup(id);
639 if (c == NULL) {
640 log("channel_register_cleanup: %d: bad id", id);
641 return;
642 }
Ben Lindstrom809744e2001-07-04 05:26:06 +0000643 c->detach_user = fn;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000644}
645void
646channel_cancel_cleanup(int id)
647{
648 Channel *c = channel_lookup(id);
649 if (c == NULL) {
650 log("channel_cancel_cleanup: %d: bad id", id);
651 return;
652 }
Ben Lindstrom809744e2001-07-04 05:26:06 +0000653 c->detach_user = NULL;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000654}
655void
656channel_register_filter(int id, channel_filter_fn *fn)
657{
658 Channel *c = channel_lookup(id);
659 if (c == NULL) {
660 log("channel_register_filter: %d: bad id", id);
661 return;
662 }
663 c->input_filter = fn;
664}
665
666void
667channel_set_fds(int id, int rfd, int wfd, int efd,
668 int extusage, int nonblock)
669{
670 Channel *c = channel_lookup(id);
671 if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
672 fatal("channel_activate for non-larval channel %d.", id);
673 channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
674 c->type = SSH_CHANNEL_OPEN;
675 /* XXX window size? */
676 c->local_window = c->local_window_max = c->local_maxpacket * 2;
677 packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
678 packet_put_int(c->remote_id);
679 packet_put_int(c->local_window);
680 packet_send();
681}
682
Damien Miller5428f641999-11-25 11:54:57 +1100683/*
Damien Millerb38eff82000-04-01 11:09:21 +1000684 * 'channel_pre*' are called just before select() to add any bits relevant to
685 * channels in the select bitmasks.
Damien Miller5428f641999-11-25 11:54:57 +1100686 */
Damien Millerb38eff82000-04-01 11:09:21 +1000687/*
688 * 'channel_post*': perform any appropriate operations for channels which
689 * have events pending.
690 */
691typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset);
692chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
693chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
694
Ben Lindstrombba81212001-06-25 05:01:22 +0000695static void
Damien Millerb38eff82000-04-01 11:09:21 +1000696channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset)
697{
698 FD_SET(c->sock, readset);
699}
700
Ben Lindstrombba81212001-06-25 05:01:22 +0000701static void
Ben Lindstrom7ad97102000-12-06 01:42:49 +0000702channel_pre_connecting(Channel *c, fd_set * readset, fd_set * writeset)
703{
704 debug3("channel %d: waiting for connection", c->self);
705 FD_SET(c->sock, writeset);
706}
707
Ben Lindstrombba81212001-06-25 05:01:22 +0000708static void
Damien Millerb38eff82000-04-01 11:09:21 +1000709channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset)
710{
711 if (buffer_len(&c->input) < packet_get_maxsize())
712 FD_SET(c->sock, readset);
713 if (buffer_len(&c->output) > 0)
714 FD_SET(c->sock, writeset);
715}
716
Ben Lindstrombba81212001-06-25 05:01:22 +0000717static void
Damien Millerb38eff82000-04-01 11:09:21 +1000718channel_pre_open_15(Channel *c, fd_set * readset, fd_set * writeset)
719{
720 /* test whether sockets are 'alive' for read/write */
721 if (c->istate == CHAN_INPUT_OPEN)
722 if (buffer_len(&c->input) < packet_get_maxsize())
723 FD_SET(c->sock, readset);
724 if (c->ostate == CHAN_OUTPUT_OPEN ||
725 c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
726 if (buffer_len(&c->output) > 0) {
727 FD_SET(c->sock, writeset);
728 } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
729 chan_obuf_empty(c);
730 }
731 }
732}
733
Ben Lindstrombba81212001-06-25 05:01:22 +0000734static void
Damien Miller33b13562000-04-04 14:38:59 +1000735channel_pre_open_20(Channel *c, fd_set * readset, fd_set * writeset)
736{
737 if (c->istate == CHAN_INPUT_OPEN &&
738 c->remote_window > 0 &&
739 buffer_len(&c->input) < c->remote_window)
740 FD_SET(c->rfd, readset);
741 if (c->ostate == CHAN_OUTPUT_OPEN ||
742 c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
743 if (buffer_len(&c->output) > 0) {
744 FD_SET(c->wfd, writeset);
745 } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
746 chan_obuf_empty(c);
747 }
748 }
749 /** XXX check close conditions, too */
750 if (c->efd != -1) {
751 if (c->extended_usage == CHAN_EXTENDED_WRITE &&
752 buffer_len(&c->extended) > 0)
753 FD_SET(c->efd, writeset);
754 else if (c->extended_usage == CHAN_EXTENDED_READ &&
755 buffer_len(&c->extended) < c->remote_window)
756 FD_SET(c->efd, readset);
757 }
758}
759
Ben Lindstrombba81212001-06-25 05:01:22 +0000760static void
Damien Millerb38eff82000-04-01 11:09:21 +1000761channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset)
762{
763 if (buffer_len(&c->input) == 0) {
764 packet_start(SSH_MSG_CHANNEL_CLOSE);
765 packet_put_int(c->remote_id);
766 packet_send();
767 c->type = SSH_CHANNEL_CLOSED;
Ben Lindstromc486d882001-04-11 16:08:34 +0000768 debug("channel %d: closing after input drain.", c->self);
Damien Millerb38eff82000-04-01 11:09:21 +1000769 }
770}
771
Ben Lindstrombba81212001-06-25 05:01:22 +0000772static void
Damien Millerb38eff82000-04-01 11:09:21 +1000773channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset)
774{
775 if (buffer_len(&c->output) == 0)
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000776 chan_mark_dead(c);
Damien Miller4af51302000-04-16 11:18:38 +1000777 else
Damien Millerb38eff82000-04-01 11:09:21 +1000778 FD_SET(c->sock, writeset);
779}
780
781/*
782 * This is a special state for X11 authentication spoofing. An opened X11
783 * connection (when authentication spoofing is being done) remains in this
784 * state until the first packet has been completely read. The authentication
785 * data in that packet is then substituted by the real data if it matches the
786 * fake data, and the channel is put into normal mode.
Damien Millerbd483e72000-04-30 10:00:53 +1000787 * XXX All this happens at the client side.
Ben Lindstrome9c99912001-06-09 00:41:05 +0000788 * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
Damien Millerb38eff82000-04-01 11:09:21 +1000789 */
Ben Lindstrombba81212001-06-25 05:01:22 +0000790static int
Ben Lindstrome9c99912001-06-09 00:41:05 +0000791x11_open_helper(Buffer *b)
Damien Millerb38eff82000-04-01 11:09:21 +1000792{
Ben Lindstrom46c16222000-12-22 01:43:59 +0000793 u_char *ucp;
794 u_int proto_len, data_len;
Damien Millerb38eff82000-04-01 11:09:21 +1000795
796 /* Check if the fixed size part of the packet is in buffer. */
Ben Lindstrome9c99912001-06-09 00:41:05 +0000797 if (buffer_len(b) < 12)
Damien Millerb38eff82000-04-01 11:09:21 +1000798 return 0;
799
800 /* Parse the lengths of variable-length fields. */
Ben Lindstrome9c99912001-06-09 00:41:05 +0000801 ucp = (u_char *) buffer_ptr(b);
Damien Millerb38eff82000-04-01 11:09:21 +1000802 if (ucp[0] == 0x42) { /* Byte order MSB first. */
803 proto_len = 256 * ucp[6] + ucp[7];
804 data_len = 256 * ucp[8] + ucp[9];
805 } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
806 proto_len = ucp[6] + 256 * ucp[7];
807 data_len = ucp[8] + 256 * ucp[9];
808 } else {
809 debug("Initial X11 packet contains bad byte order byte: 0x%x",
810 ucp[0]);
811 return -1;
812 }
813
814 /* Check if the whole packet is in buffer. */
Ben Lindstrome9c99912001-06-09 00:41:05 +0000815 if (buffer_len(b) <
Damien Millerb38eff82000-04-01 11:09:21 +1000816 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
817 return 0;
818
819 /* Check if authentication protocol matches. */
820 if (proto_len != strlen(x11_saved_proto) ||
821 memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
822 debug("X11 connection uses different authentication protocol.");
823 return -1;
824 }
825 /* Check if authentication data matches our fake data. */
826 if (data_len != x11_fake_data_len ||
827 memcmp(ucp + 12 + ((proto_len + 3) & ~3),
828 x11_fake_data, x11_fake_data_len) != 0) {
829 debug("X11 auth data does not match fake data.");
830 return -1;
831 }
832 /* Check fake data length */
833 if (x11_fake_data_len != x11_saved_data_len) {
834 error("X11 fake_data_len %d != saved_data_len %d",
835 x11_fake_data_len, x11_saved_data_len);
836 return -1;
837 }
838 /*
839 * Received authentication protocol and data match
840 * our fake data. Substitute the fake data with real
841 * data.
842 */
843 memcpy(ucp + 12 + ((proto_len + 3) & ~3),
844 x11_saved_data, x11_saved_data_len);
845 return 1;
846}
847
Ben Lindstrombba81212001-06-25 05:01:22 +0000848static void
Damien Millerb38eff82000-04-01 11:09:21 +1000849channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset)
850{
Ben Lindstrome9c99912001-06-09 00:41:05 +0000851 int ret = x11_open_helper(&c->output);
Damien Millerb38eff82000-04-01 11:09:21 +1000852 if (ret == 1) {
853 /* Start normal processing for the channel. */
854 c->type = SSH_CHANNEL_OPEN;
Damien Miller78928792000-04-12 20:17:38 +1000855 channel_pre_open_13(c, readset, writeset);
Damien Millerb38eff82000-04-01 11:09:21 +1000856 } else if (ret == -1) {
857 /*
858 * We have received an X11 connection that has bad
859 * authentication information.
860 */
Ben Lindstrom6df8ef42001-03-05 07:47:23 +0000861 log("X11 connection rejected because of wrong authentication.");
Damien Millerb38eff82000-04-01 11:09:21 +1000862 buffer_clear(&c->input);
863 buffer_clear(&c->output);
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000864 channel_close_fd(&c->sock);
Damien Millerb38eff82000-04-01 11:09:21 +1000865 c->sock = -1;
866 c->type = SSH_CHANNEL_CLOSED;
867 packet_start(SSH_MSG_CHANNEL_CLOSE);
868 packet_put_int(c->remote_id);
869 packet_send();
870 }
871}
872
Ben Lindstrombba81212001-06-25 05:01:22 +0000873static void
Damien Millerbd483e72000-04-30 10:00:53 +1000874channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset)
Damien Millerb38eff82000-04-01 11:09:21 +1000875{
Ben Lindstrome9c99912001-06-09 00:41:05 +0000876 int ret = x11_open_helper(&c->output);
Damien Millerb38eff82000-04-01 11:09:21 +1000877 if (ret == 1) {
878 c->type = SSH_CHANNEL_OPEN;
Damien Miller30c3d422000-05-09 11:02:59 +1000879 if (compat20)
880 channel_pre_open_20(c, readset, writeset);
881 else
882 channel_pre_open_15(c, readset, writeset);
Damien Millerb38eff82000-04-01 11:09:21 +1000883 } else if (ret == -1) {
884 debug("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
Damien Millerbd483e72000-04-30 10:00:53 +1000885 chan_read_failed(c); /** force close? */
Damien Millerb38eff82000-04-01 11:09:21 +1000886 chan_write_failed(c);
887 debug("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
888 }
889}
890
Ben Lindstromb3921512001-04-11 15:57:50 +0000891/* try to decode a socks4 header */
Ben Lindstrombba81212001-06-25 05:01:22 +0000892static int
Ben Lindstromb3921512001-04-11 15:57:50 +0000893channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset)
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000894{
895 u_char *p, *host;
Ben Lindstrom2b261b92001-04-17 18:14:34 +0000896 int len, have, i, found;
Ben Lindstromb3921512001-04-11 15:57:50 +0000897 char username[256];
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000898 struct {
899 u_int8_t version;
900 u_int8_t command;
901 u_int16_t dest_port;
Ben Lindstromb3921512001-04-11 15:57:50 +0000902 struct in_addr dest_addr;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000903 } s4_req, s4_rsp;
904
Ben Lindstromb3921512001-04-11 15:57:50 +0000905 debug2("channel %d: decode socks4", c->self);
Ben Lindstrom2b261b92001-04-17 18:14:34 +0000906
907 have = buffer_len(&c->input);
908 len = sizeof(s4_req);
909 if (have < len)
910 return 0;
911 p = buffer_ptr(&c->input);
912 for (found = 0, i = len; i < have; i++) {
913 if (p[i] == '\0') {
914 found = 1;
915 break;
916 }
917 if (i > 1024) {
918 /* the peer is probably sending garbage */
919 debug("channel %d: decode socks4: too long",
920 c->self);
921 return -1;
922 }
923 }
924 if (!found)
925 return 0;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000926 buffer_get(&c->input, (char *)&s4_req.version, 1);
927 buffer_get(&c->input, (char *)&s4_req.command, 1);
928 buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
Ben Lindstromb3921512001-04-11 15:57:50 +0000929 buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
Ben Lindstrom2b261b92001-04-17 18:14:34 +0000930 have = buffer_len(&c->input);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000931 p = buffer_ptr(&c->input);
932 len = strlen(p);
Ben Lindstrom6fa9d102001-04-11 23:08:17 +0000933 debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000934 if (len > have)
Ben Lindstromb3921512001-04-11 15:57:50 +0000935 fatal("channel %d: decode socks4: len %d > have %d",
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000936 c->self, len, have);
937 strlcpy(username, p, sizeof(username));
938 buffer_consume(&c->input, len);
939 buffer_consume(&c->input, 1); /* trailing '\0' */
940
Ben Lindstromb3921512001-04-11 15:57:50 +0000941 host = inet_ntoa(s4_req.dest_addr);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000942 strlcpy(c->path, host, sizeof(c->path));
943 c->host_port = ntohs(s4_req.dest_port);
944
Ben Lindstrom6fa9d102001-04-11 23:08:17 +0000945 debug("channel %d: dynamic request: socks4 host %s port %u command %u",
946 c->self, host, c->host_port, s4_req.command);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000947
Ben Lindstromb3921512001-04-11 15:57:50 +0000948 if (s4_req.command != 1) {
949 debug("channel %d: cannot handle: socks4 cn %d",
950 c->self, s4_req.command);
951 return -1;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000952 }
Ben Lindstromb3921512001-04-11 15:57:50 +0000953 s4_rsp.version = 0; /* vn: 0 for reply */
954 s4_rsp.command = 90; /* cd: req granted */
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000955 s4_rsp.dest_port = 0; /* ignored */
Ben Lindstromb3921512001-04-11 15:57:50 +0000956 s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000957 buffer_append(&c->output, (char *)&s4_rsp, sizeof(s4_rsp));
Ben Lindstromb3921512001-04-11 15:57:50 +0000958 return 1;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000959}
960
Ben Lindstromb3921512001-04-11 15:57:50 +0000961/* dynamic port forwarding */
Ben Lindstrombba81212001-06-25 05:01:22 +0000962static void
Ben Lindstromb3921512001-04-11 15:57:50 +0000963channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset)
964{
965 u_char *p;
966 int have, ret;
967
968 have = buffer_len(&c->input);
969
970 debug2("channel %d: pre_dynamic: have %d", c->self, have);
Ben Lindstromc486d882001-04-11 16:08:34 +0000971 /* buffer_dump(&c->input); */
Ben Lindstromb3921512001-04-11 15:57:50 +0000972 /* check if the fixed size part of the packet is in buffer. */
973 if (have < 4) {
974 /* need more */
975 FD_SET(c->sock, readset);
976 return;
977 }
978 /* try to guess the protocol */
979 p = buffer_ptr(&c->input);
980 switch (p[0]) {
Ben Lindstrom6fa9d102001-04-11 23:08:17 +0000981 case 0x04:
982 ret = channel_decode_socks4(c, readset, writeset);
983 break;
Ben Lindstromb3921512001-04-11 15:57:50 +0000984 default:
985 ret = -1;
986 break;
987 }
988 if (ret < 0) {
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000989 chan_mark_dead(c);
Ben Lindstromb3921512001-04-11 15:57:50 +0000990 } else if (ret == 0) {
991 debug2("channel %d: pre_dynamic: need more", c->self);
992 /* need more */
993 FD_SET(c->sock, readset);
994 } else {
995 /* switch to the next state */
996 c->type = SSH_CHANNEL_OPENING;
997 port_open_helper(c, "direct-tcpip");
998 }
999}
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001000
Damien Millerb38eff82000-04-01 11:09:21 +10001001/* This is our fake X11 server socket. */
Ben Lindstrombba81212001-06-25 05:01:22 +00001002static void
Damien Millerb38eff82000-04-01 11:09:21 +10001003channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset)
1004{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001005 Channel *nc;
Damien Millerb38eff82000-04-01 11:09:21 +10001006 struct sockaddr addr;
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001007 int newsock;
Damien Millerb38eff82000-04-01 11:09:21 +10001008 socklen_t addrlen;
Damien Millerd83ff352001-01-30 09:19:34 +11001009 char buf[16384], *remote_ipaddr;
Damien Millerbd483e72000-04-30 10:00:53 +10001010 int remote_port;
Damien Millerb38eff82000-04-01 11:09:21 +10001011
1012 if (FD_ISSET(c->sock, readset)) {
1013 debug("X11 connection requested.");
1014 addrlen = sizeof(addr);
1015 newsock = accept(c->sock, &addr, &addrlen);
1016 if (newsock < 0) {
1017 error("accept: %.100s", strerror(errno));
1018 return;
1019 }
Damien Millerd83ff352001-01-30 09:19:34 +11001020 remote_ipaddr = get_peer_ipaddr(newsock);
Damien Millerbd483e72000-04-30 10:00:53 +10001021 remote_port = get_peer_port(newsock);
Damien Millerb38eff82000-04-01 11:09:21 +10001022 snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
Damien Millerd83ff352001-01-30 09:19:34 +11001023 remote_ipaddr, remote_port);
Damien Millerbd483e72000-04-30 10:00:53 +10001024
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001025 nc = channel_new("accepted x11 socket",
Damien Millerbd483e72000-04-30 10:00:53 +10001026 SSH_CHANNEL_OPENING, newsock, newsock, -1,
1027 c->local_window_max, c->local_maxpacket,
Damien Miller69b69aa2000-10-28 14:19:58 +11001028 0, xstrdup(buf), 1);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001029 if (nc == NULL) {
1030 close(newsock);
1031 xfree(remote_ipaddr);
1032 return;
1033 }
Damien Millerbd483e72000-04-30 10:00:53 +10001034 if (compat20) {
1035 packet_start(SSH2_MSG_CHANNEL_OPEN);
1036 packet_put_cstring("x11");
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001037 packet_put_int(nc->self);
Damien Millerbd483e72000-04-30 10:00:53 +10001038 packet_put_int(c->local_window_max);
1039 packet_put_int(c->local_maxpacket);
Damien Millerd83ff352001-01-30 09:19:34 +11001040 /* originator ipaddr and port */
1041 packet_put_cstring(remote_ipaddr);
Damien Miller30c3d422000-05-09 11:02:59 +10001042 if (datafellows & SSH_BUG_X11FWD) {
1043 debug("ssh2 x11 bug compat mode");
1044 } else {
1045 packet_put_int(remote_port);
1046 }
Damien Millerbd483e72000-04-30 10:00:53 +10001047 packet_send();
1048 } else {
1049 packet_start(SSH_SMSG_X11_OPEN);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001050 packet_put_int(nc->self);
Ben Lindstrome9c99912001-06-09 00:41:05 +00001051 if (packet_get_protocol_flags() &
1052 SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
Ben Lindstrom664408d2001-06-09 01:42:01 +00001053 packet_put_cstring(buf);
Damien Millerbd483e72000-04-30 10:00:53 +10001054 packet_send();
1055 }
Damien Millerd83ff352001-01-30 09:19:34 +11001056 xfree(remote_ipaddr);
Damien Millerb38eff82000-04-01 11:09:21 +10001057 }
1058}
1059
Ben Lindstrombba81212001-06-25 05:01:22 +00001060static void
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001061port_open_helper(Channel *c, char *rtype)
1062{
1063 int direct;
1064 char buf[1024];
1065 char *remote_ipaddr = get_peer_ipaddr(c->sock);
1066 u_short remote_port = get_peer_port(c->sock);
1067
1068 direct = (strcmp(rtype, "direct-tcpip") == 0);
1069
1070 snprintf(buf, sizeof buf,
1071 "%s: listening port %d for %.100s port %d, "
1072 "connect from %.200s port %d",
1073 rtype, c->listening_port, c->path, c->host_port,
1074 remote_ipaddr, remote_port);
1075
1076 xfree(c->remote_name);
1077 c->remote_name = xstrdup(buf);
1078
1079 if (compat20) {
1080 packet_start(SSH2_MSG_CHANNEL_OPEN);
1081 packet_put_cstring(rtype);
1082 packet_put_int(c->self);
1083 packet_put_int(c->local_window_max);
1084 packet_put_int(c->local_maxpacket);
1085 if (direct) {
1086 /* target host, port */
1087 packet_put_cstring(c->path);
1088 packet_put_int(c->host_port);
1089 } else {
1090 /* listen address, port */
1091 packet_put_cstring(c->path);
1092 packet_put_int(c->listening_port);
1093 }
1094 /* originator host and port */
1095 packet_put_cstring(remote_ipaddr);
1096 packet_put_int(remote_port);
1097 packet_send();
1098 } else {
1099 packet_start(SSH_MSG_PORT_OPEN);
1100 packet_put_int(c->self);
1101 packet_put_cstring(c->path);
1102 packet_put_int(c->host_port);
Ben Lindstrome9c99912001-06-09 00:41:05 +00001103 if (packet_get_protocol_flags() &
1104 SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001105 packet_put_cstring(c->remote_name);
1106 packet_send();
1107 }
1108 xfree(remote_ipaddr);
1109}
1110
Damien Millerb38eff82000-04-01 11:09:21 +10001111/*
1112 * This socket is listening for connections to a forwarded TCP/IP port.
1113 */
Ben Lindstrombba81212001-06-25 05:01:22 +00001114static void
Damien Millerb38eff82000-04-01 11:09:21 +10001115channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset)
1116{
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001117 Channel *nc;
Damien Millerb38eff82000-04-01 11:09:21 +10001118 struct sockaddr addr;
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001119 int newsock, nextstate;
Damien Millerb38eff82000-04-01 11:09:21 +10001120 socklen_t addrlen;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001121 char *rtype;
Damien Miller0bc1bd82000-11-13 22:57:25 +11001122
Damien Millerb38eff82000-04-01 11:09:21 +10001123 if (FD_ISSET(c->sock, readset)) {
1124 debug("Connection to port %d forwarding "
1125 "to %.100s port %d requested.",
1126 c->listening_port, c->path, c->host_port);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001127
1128 rtype = (c->type == SSH_CHANNEL_RPORT_LISTENER) ?
1129 "forwarded-tcpip" : "direct-tcpip";
Ben Lindstrom6d618462001-05-10 23:24:49 +00001130 nextstate = (c->host_port == 0 &&
1131 c->type != SSH_CHANNEL_RPORT_LISTENER) ?
1132 SSH_CHANNEL_DYNAMIC : SSH_CHANNEL_OPENING;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001133
Damien Millerb38eff82000-04-01 11:09:21 +10001134 addrlen = sizeof(addr);
1135 newsock = accept(c->sock, &addr, &addrlen);
1136 if (newsock < 0) {
1137 error("accept: %.100s", strerror(errno));
1138 return;
1139 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001140 nc = channel_new(rtype,
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001141 nextstate, newsock, newsock, -1,
Damien Millerb38eff82000-04-01 11:09:21 +10001142 c->local_window_max, c->local_maxpacket,
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001143 0, xstrdup(rtype), 1);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001144 if (nc == NULL) {
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001145 error("channel_post_port_listener: no new channel:");
1146 close(newsock);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001147 return;
Damien Millerb38eff82000-04-01 11:09:21 +10001148 }
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001149 nc->listening_port = c->listening_port;
1150 nc->host_port = c->host_port;
1151 strlcpy(nc->path, c->path, sizeof(nc->path));
1152
1153 if (nextstate != SSH_CHANNEL_DYNAMIC)
1154 port_open_helper(nc, rtype);
Damien Millerb38eff82000-04-01 11:09:21 +10001155 }
1156}
1157
1158/*
1159 * This is the authentication agent socket listening for connections from
1160 * clients.
1161 */
Ben Lindstrombba81212001-06-25 05:01:22 +00001162static void
Damien Millerb38eff82000-04-01 11:09:21 +10001163channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset)
1164{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001165 Channel *nc;
Ben Lindstrome9c99912001-06-09 00:41:05 +00001166 char *name;
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001167 int newsock;
Damien Millerb38eff82000-04-01 11:09:21 +10001168 struct sockaddr addr;
Damien Millerb38eff82000-04-01 11:09:21 +10001169 socklen_t addrlen;
1170
1171 if (FD_ISSET(c->sock, readset)) {
1172 addrlen = sizeof(addr);
1173 newsock = accept(c->sock, &addr, &addrlen);
1174 if (newsock < 0) {
1175 error("accept from auth socket: %.100s", strerror(errno));
1176 return;
1177 }
Ben Lindstrome9c99912001-06-09 00:41:05 +00001178 name = xstrdup("accepted auth socket");
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001179 nc = channel_new("accepted auth socket",
Damien Miller0bc1bd82000-11-13 22:57:25 +11001180 SSH_CHANNEL_OPENING, newsock, newsock, -1,
1181 c->local_window_max, c->local_maxpacket,
Ben Lindstrome9c99912001-06-09 00:41:05 +00001182 0, name, 1);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001183 if (nc == NULL) {
1184 error("channel_post_auth_listener: channel_new failed");
Ben Lindstrome9c99912001-06-09 00:41:05 +00001185 xfree(name);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001186 close(newsock);
1187 }
Damien Miller0bc1bd82000-11-13 22:57:25 +11001188 if (compat20) {
1189 packet_start(SSH2_MSG_CHANNEL_OPEN);
1190 packet_put_cstring("auth-agent@openssh.com");
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001191 packet_put_int(nc->self);
Damien Miller0bc1bd82000-11-13 22:57:25 +11001192 packet_put_int(c->local_window_max);
1193 packet_put_int(c->local_maxpacket);
1194 } else {
1195 packet_start(SSH_SMSG_AGENT_OPEN);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001196 packet_put_int(nc->self);
Damien Miller0bc1bd82000-11-13 22:57:25 +11001197 }
Damien Millerb38eff82000-04-01 11:09:21 +10001198 packet_send();
1199 }
1200}
1201
Ben Lindstrombba81212001-06-25 05:01:22 +00001202static void
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001203channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset)
1204{
Ben Lindstrom69128662001-05-08 20:07:39 +00001205 int err = 0;
Ben Lindstrom11180952001-07-04 05:13:35 +00001206 socklen_t sz = sizeof(err);
Ben Lindstrom69128662001-05-08 20:07:39 +00001207
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001208 if (FD_ISSET(c->sock, writeset)) {
Ben Lindstrom69128662001-05-08 20:07:39 +00001209 if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, (char *)&err,
1210 &sz) < 0) {
1211 err = errno;
1212 error("getsockopt SO_ERROR failed");
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001213 }
Ben Lindstrom69128662001-05-08 20:07:39 +00001214 if (err == 0) {
1215 debug("channel %d: connected", c->self);
1216 c->type = SSH_CHANNEL_OPEN;
1217 if (compat20) {
1218 packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1219 packet_put_int(c->remote_id);
1220 packet_put_int(c->self);
1221 packet_put_int(c->local_window);
1222 packet_put_int(c->local_maxpacket);
1223 } else {
1224 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1225 packet_put_int(c->remote_id);
1226 packet_put_int(c->self);
1227 }
1228 } else {
1229 debug("channel %d: not connected: %s",
1230 c->self, strerror(err));
1231 if (compat20) {
1232 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1233 packet_put_int(c->remote_id);
1234 packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1235 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1236 packet_put_cstring(strerror(err));
1237 packet_put_cstring("");
1238 }
1239 } else {
1240 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1241 packet_put_int(c->remote_id);
1242 }
1243 chan_mark_dead(c);
1244 }
1245 packet_send();
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001246 }
1247}
1248
Ben Lindstrombba81212001-06-25 05:01:22 +00001249static int
Damien Millerb38eff82000-04-01 11:09:21 +10001250channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset)
1251{
1252 char buf[16*1024];
1253 int len;
1254
Ben Lindstromc0dee1a2001-06-05 20:52:50 +00001255 if (c->rfd != -1 &&
Damien Millerb38eff82000-04-01 11:09:21 +10001256 FD_ISSET(c->rfd, readset)) {
1257 len = read(c->rfd, buf, sizeof(buf));
Damien Miller6f83b8e2000-05-02 09:23:45 +10001258 if (len < 0 && (errno == EINTR || errno == EAGAIN))
1259 return 1;
Damien Millerb38eff82000-04-01 11:09:21 +10001260 if (len <= 0) {
Damien Millerbd483e72000-04-30 10:00:53 +10001261 debug("channel %d: read<=0 rfd %d len %d",
Damien Millerb38eff82000-04-01 11:09:21 +10001262 c->self, c->rfd, len);
Ben Lindstromb3921512001-04-11 15:57:50 +00001263 if (c->type != SSH_CHANNEL_OPEN) {
1264 debug("channel %d: not open", c->self);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001265 chan_mark_dead(c);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001266 return -1;
Ben Lindstromb3921512001-04-11 15:57:50 +00001267 } else if (compat13) {
Damien Millerb38eff82000-04-01 11:09:21 +10001268 buffer_consume(&c->output, buffer_len(&c->output));
1269 c->type = SSH_CHANNEL_INPUT_DRAINING;
Ben Lindstrome9c99912001-06-09 00:41:05 +00001270 debug("channel %d: input draining.", c->self);
Damien Millerb38eff82000-04-01 11:09:21 +10001271 } else {
1272 chan_read_failed(c);
1273 }
1274 return -1;
1275 }
Damien Millerad833b32000-08-23 10:46:23 +10001276 if(c->input_filter != NULL) {
1277 if (c->input_filter(c, buf, len) == -1) {
Ben Lindstromc486d882001-04-11 16:08:34 +00001278 debug("channel %d: filter stops", c->self);
Damien Millerad833b32000-08-23 10:46:23 +10001279 chan_read_failed(c);
1280 }
1281 } else {
1282 buffer_append(&c->input, buf, len);
1283 }
Damien Millerb38eff82000-04-01 11:09:21 +10001284 }
1285 return 1;
1286}
Ben Lindstrombba81212001-06-25 05:01:22 +00001287static int
Damien Millerb38eff82000-04-01 11:09:21 +10001288channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset)
1289{
Ben Lindstrome229b252001-03-05 06:28:06 +00001290 struct termios tio;
Damien Millerb38eff82000-04-01 11:09:21 +10001291 int len;
1292
1293 /* Send buffered output data to the socket. */
Ben Lindstromc0dee1a2001-06-05 20:52:50 +00001294 if (c->wfd != -1 &&
Damien Millerb38eff82000-04-01 11:09:21 +10001295 FD_ISSET(c->wfd, writeset) &&
1296 buffer_len(&c->output) > 0) {
1297 len = write(c->wfd, buffer_ptr(&c->output),
Damien Miller6f83b8e2000-05-02 09:23:45 +10001298 buffer_len(&c->output));
1299 if (len < 0 && (errno == EINTR || errno == EAGAIN))
1300 return 1;
Damien Millerb38eff82000-04-01 11:09:21 +10001301 if (len <= 0) {
Ben Lindstromb3921512001-04-11 15:57:50 +00001302 if (c->type != SSH_CHANNEL_OPEN) {
1303 debug("channel %d: not open", c->self);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001304 chan_mark_dead(c);
Ben Lindstromb3921512001-04-11 15:57:50 +00001305 return -1;
1306 } else if (compat13) {
Damien Millerb38eff82000-04-01 11:09:21 +10001307 buffer_consume(&c->output, buffer_len(&c->output));
Ben Lindstrome9c99912001-06-09 00:41:05 +00001308 debug("channel %d: input draining.", c->self);
Damien Millerb38eff82000-04-01 11:09:21 +10001309 c->type = SSH_CHANNEL_INPUT_DRAINING;
1310 } else {
1311 chan_write_failed(c);
1312 }
1313 return -1;
1314 }
Damien Miller79438cc2001-02-16 12:34:57 +11001315 if (compat20 && c->isatty) {
Damien Miller79438cc2001-02-16 12:34:57 +11001316 if (tcgetattr(c->wfd, &tio) == 0 &&
1317 !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1318 /*
1319 * Simulate echo to reduce the impact of
Ben Lindstromb40204b2001-03-05 06:29:44 +00001320 * traffic analysis. We need to match the
Ben Lindstrome229b252001-03-05 06:28:06 +00001321 * size of a SSH2_MSG_CHANNEL_DATA message
1322 * (4 byte channel id + data)
Damien Miller79438cc2001-02-16 12:34:57 +11001323 */
Ben Lindstrome229b252001-03-05 06:28:06 +00001324 packet_send_ignore(4 + len);
Damien Miller79438cc2001-02-16 12:34:57 +11001325 packet_send();
Damien Miller79438cc2001-02-16 12:34:57 +11001326 }
1327 }
Damien Millerb38eff82000-04-01 11:09:21 +10001328 buffer_consume(&c->output, len);
Damien Miller33b13562000-04-04 14:38:59 +10001329 if (compat20 && len > 0) {
1330 c->local_consumed += len;
1331 }
1332 }
1333 return 1;
1334}
Ben Lindstrombba81212001-06-25 05:01:22 +00001335static int
Damien Miller33b13562000-04-04 14:38:59 +10001336channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset)
1337{
1338 char buf[16*1024];
1339 int len;
1340
Damien Miller1383bd82000-04-06 12:32:37 +10001341/** XXX handle drain efd, too */
Damien Miller33b13562000-04-04 14:38:59 +10001342 if (c->efd != -1) {
1343 if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1344 FD_ISSET(c->efd, writeset) &&
1345 buffer_len(&c->extended) > 0) {
1346 len = write(c->efd, buffer_ptr(&c->extended),
1347 buffer_len(&c->extended));
Damien Millerd3444942000-09-30 14:20:03 +11001348 debug2("channel %d: written %d to efd %d",
Damien Miller33b13562000-04-04 14:38:59 +10001349 c->self, len, c->efd);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001350 if (len < 0 && (errno == EINTR || errno == EAGAIN))
1351 return 1;
1352 if (len <= 0) {
1353 debug2("channel %d: closing write-efd %d",
1354 c->self, c->efd);
Ben Lindstrom16d29d52001-07-18 16:01:46 +00001355 channel_close_fd(&c->efd);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001356 } else {
Damien Miller33b13562000-04-04 14:38:59 +10001357 buffer_consume(&c->extended, len);
1358 c->local_consumed += len;
1359 }
1360 } else if (c->extended_usage == CHAN_EXTENDED_READ &&
1361 FD_ISSET(c->efd, readset)) {
1362 len = read(c->efd, buf, sizeof(buf));
Damien Millerd3444942000-09-30 14:20:03 +11001363 debug2("channel %d: read %d from efd %d",
Damien Miller33b13562000-04-04 14:38:59 +10001364 c->self, len, c->efd);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001365 if (len < 0 && (errno == EINTR || errno == EAGAIN))
1366 return 1;
1367 if (len <= 0) {
1368 debug2("channel %d: closing read-efd %d",
Damien Miller1383bd82000-04-06 12:32:37 +10001369 c->self, c->efd);
Ben Lindstrom16d29d52001-07-18 16:01:46 +00001370 channel_close_fd(&c->efd);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001371 } else {
Damien Miller33b13562000-04-04 14:38:59 +10001372 buffer_append(&c->extended, buf, len);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001373 }
Damien Miller33b13562000-04-04 14:38:59 +10001374 }
1375 }
1376 return 1;
1377}
Ben Lindstrombba81212001-06-25 05:01:22 +00001378static int
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001379channel_check_window(Channel *c)
Damien Miller33b13562000-04-04 14:38:59 +10001380{
Ben Lindstromb3921512001-04-11 15:57:50 +00001381 if (c->type == SSH_CHANNEL_OPEN &&
1382 !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
Damien Miller33b13562000-04-04 14:38:59 +10001383 c->local_window < c->local_window_max/2 &&
1384 c->local_consumed > 0) {
1385 packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1386 packet_put_int(c->remote_id);
1387 packet_put_int(c->local_consumed);
1388 packet_send();
Damien Millerd3444942000-09-30 14:20:03 +11001389 debug2("channel %d: window %d sent adjust %d",
Damien Miller33b13562000-04-04 14:38:59 +10001390 c->self, c->local_window,
1391 c->local_consumed);
1392 c->local_window += c->local_consumed;
1393 c->local_consumed = 0;
Damien Millerb38eff82000-04-01 11:09:21 +10001394 }
1395 return 1;
1396}
1397
Ben Lindstrombba81212001-06-25 05:01:22 +00001398static void
Damien Millerb38eff82000-04-01 11:09:21 +10001399channel_post_open_1(Channel *c, fd_set * readset, fd_set * writeset)
1400{
1401 channel_handle_rfd(c, readset, writeset);
1402 channel_handle_wfd(c, readset, writeset);
1403}
1404
Ben Lindstrombba81212001-06-25 05:01:22 +00001405static void
Damien Miller33b13562000-04-04 14:38:59 +10001406channel_post_open_2(Channel *c, fd_set * readset, fd_set * writeset)
1407{
1408 channel_handle_rfd(c, readset, writeset);
1409 channel_handle_wfd(c, readset, writeset);
1410 channel_handle_efd(c, readset, writeset);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001411
1412 channel_check_window(c);
Damien Miller33b13562000-04-04 14:38:59 +10001413}
1414
Ben Lindstrombba81212001-06-25 05:01:22 +00001415static void
Damien Millerb38eff82000-04-01 11:09:21 +10001416channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset)
1417{
1418 int len;
1419 /* Send buffered output data to the socket. */
1420 if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
1421 len = write(c->sock, buffer_ptr(&c->output),
1422 buffer_len(&c->output));
1423 if (len <= 0)
1424 buffer_consume(&c->output, buffer_len(&c->output));
1425 else
1426 buffer_consume(&c->output, len);
1427 }
1428}
1429
Ben Lindstrombba81212001-06-25 05:01:22 +00001430static void
Damien Miller33b13562000-04-04 14:38:59 +10001431channel_handler_init_20(void)
1432{
1433 channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_20;
Damien Millerbd483e72000-04-30 10:00:53 +10001434 channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
Damien Miller33b13562000-04-04 14:38:59 +10001435 channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
Damien Miller0bc1bd82000-11-13 22:57:25 +11001436 channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
Damien Millerbd483e72000-04-30 10:00:53 +10001437 channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
Damien Miller0bc1bd82000-11-13 22:57:25 +11001438 channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001439 channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001440 channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
Damien Miller33b13562000-04-04 14:38:59 +10001441
1442 channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_2;
1443 channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
Damien Miller0bc1bd82000-11-13 22:57:25 +11001444 channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
Damien Millerbd483e72000-04-30 10:00:53 +10001445 channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
Damien Miller0bc1bd82000-11-13 22:57:25 +11001446 channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001447 channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
Ben Lindstromb3921512001-04-11 15:57:50 +00001448 channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_2;
Damien Miller33b13562000-04-04 14:38:59 +10001449}
1450
Ben Lindstrombba81212001-06-25 05:01:22 +00001451static void
Damien Millerb38eff82000-04-01 11:09:21 +10001452channel_handler_init_13(void)
1453{
1454 channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
1455 channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
1456 channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1457 channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1458 channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1459 channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
1460 channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001461 channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001462 channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
Damien Millerb38eff82000-04-01 11:09:21 +10001463
1464 channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1;
1465 channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1466 channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1467 channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1468 channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001469 channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
Ben Lindstromb3921512001-04-11 15:57:50 +00001470 channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1;
Damien Millerb38eff82000-04-01 11:09:21 +10001471}
1472
Ben Lindstrombba81212001-06-25 05:01:22 +00001473static void
Damien Millerb38eff82000-04-01 11:09:21 +10001474channel_handler_init_15(void)
1475{
1476 channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_15;
Damien Millerbd483e72000-04-30 10:00:53 +10001477 channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
Damien Millerb38eff82000-04-01 11:09:21 +10001478 channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1479 channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1480 channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001481 channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001482 channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
Damien Millerb38eff82000-04-01 11:09:21 +10001483
1484 channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1485 channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1486 channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1487 channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001488 channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
Ben Lindstromb3921512001-04-11 15:57:50 +00001489 channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1;
Damien Millerb38eff82000-04-01 11:09:21 +10001490}
1491
Ben Lindstrombba81212001-06-25 05:01:22 +00001492static void
Damien Millerb38eff82000-04-01 11:09:21 +10001493channel_handler_init(void)
1494{
1495 int i;
1496 for(i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
1497 channel_pre[i] = NULL;
1498 channel_post[i] = NULL;
1499 }
Damien Miller33b13562000-04-04 14:38:59 +10001500 if (compat20)
1501 channel_handler_init_20();
1502 else if (compat13)
Damien Millerb38eff82000-04-01 11:09:21 +10001503 channel_handler_init_13();
1504 else
1505 channel_handler_init_15();
1506}
1507
Ben Lindstrombba81212001-06-25 05:01:22 +00001508static void
Damien Millerb38eff82000-04-01 11:09:21 +10001509channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset)
1510{
1511 static int did_init = 0;
1512 int i;
1513 Channel *c;
1514
1515 if (!did_init) {
1516 channel_handler_init();
1517 did_init = 1;
1518 }
1519 for (i = 0; i < channels_alloc; i++) {
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001520 c = channels[i];
1521 if (c == NULL)
Damien Millerb38eff82000-04-01 11:09:21 +10001522 continue;
Ben Lindstromc0dee1a2001-06-05 20:52:50 +00001523 if (ftab[c->type] != NULL)
1524 (*ftab[c->type])(c, readset, writeset);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001525 if (chan_is_dead(c)) {
1526 /*
1527 * we have to remove the fd's from the select mask
1528 * before the channels are free'd and the fd's are
1529 * closed
1530 */
1531 if (c->wfd != -1)
1532 FD_CLR(c->wfd, writeset);
1533 if (c->rfd != -1)
1534 FD_CLR(c->rfd, readset);
1535 if (c->efd != -1) {
1536 if (c->extended_usage == CHAN_EXTENDED_READ)
1537 FD_CLR(c->efd, readset);
1538 if (c->extended_usage == CHAN_EXTENDED_WRITE)
1539 FD_CLR(c->efd, writeset);
1540 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001541 channel_free(c);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001542 }
Damien Millerb38eff82000-04-01 11:09:21 +10001543 }
1544}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001545
Ben Lindstrome9c99912001-06-09 00:41:05 +00001546/*
1547 * Allocate/update select bitmasks and add any bits relevant to channels in
1548 * select bitmasks.
1549 */
Damien Miller4af51302000-04-16 11:18:38 +10001550void
Ben Lindstrombe2cc432001-04-04 23:46:07 +00001551channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
Ben Lindstrom16d29d52001-07-18 16:01:46 +00001552 int *nallocp, int rekeying)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001553{
Damien Miller5e953212001-01-30 09:14:00 +11001554 int n;
1555 u_int sz;
1556
1557 n = MAX(*maxfdp, channel_max_fd);
1558
1559 sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
Ben Lindstrom16d29d52001-07-18 16:01:46 +00001560 /* perhaps check sz < nalloc/2 and shrink? */
1561 if (*readsetp == NULL || sz > *nallocp) {
1562 *readsetp = xrealloc(*readsetp, sz);
1563 *writesetp = xrealloc(*writesetp, sz);
1564 *nallocp = sz;
Damien Miller5e953212001-01-30 09:14:00 +11001565 }
Ben Lindstrom16d29d52001-07-18 16:01:46 +00001566 *maxfdp = n;
Damien Miller5e953212001-01-30 09:14:00 +11001567 memset(*readsetp, 0, sz);
1568 memset(*writesetp, 0, sz);
1569
Ben Lindstrombe2cc432001-04-04 23:46:07 +00001570 if (!rekeying)
1571 channel_handler(channel_pre, *readsetp, *writesetp);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001572}
1573
Ben Lindstrome9c99912001-06-09 00:41:05 +00001574/*
1575 * After select, perform any appropriate operations for channels which have
1576 * events pending.
1577 */
Damien Miller4af51302000-04-16 11:18:38 +10001578void
Damien Miller95def091999-11-25 00:26:21 +11001579channel_after_select(fd_set * readset, fd_set * writeset)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001580{
Damien Millerb38eff82000-04-01 11:09:21 +10001581 channel_handler(channel_post, readset, writeset);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001582}
1583
Ben Lindstrome9c99912001-06-09 00:41:05 +00001584
Damien Miller5e953212001-01-30 09:14:00 +11001585/* If there is data to send to the connection, enqueue some of it now. */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001586
Damien Miller4af51302000-04-16 11:18:38 +10001587void
Damien Miller95def091999-11-25 00:26:21 +11001588channel_output_poll()
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001589{
Damien Miller95def091999-11-25 00:26:21 +11001590 int len, i;
Damien Millerb38eff82000-04-01 11:09:21 +10001591 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001592
Damien Miller95def091999-11-25 00:26:21 +11001593 for (i = 0; i < channels_alloc; i++) {
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001594 c = channels[i];
1595 if (c == NULL)
1596 continue;
Damien Miller34132e52000-01-14 15:45:46 +11001597
Ben Lindstrome9c99912001-06-09 00:41:05 +00001598 /*
1599 * We are only interested in channels that can have buffered
1600 * incoming data.
1601 */
Damien Miller34132e52000-01-14 15:45:46 +11001602 if (compat13) {
Damien Millerb38eff82000-04-01 11:09:21 +10001603 if (c->type != SSH_CHANNEL_OPEN &&
1604 c->type != SSH_CHANNEL_INPUT_DRAINING)
Damien Miller34132e52000-01-14 15:45:46 +11001605 continue;
1606 } else {
Damien Millerb38eff82000-04-01 11:09:21 +10001607 if (c->type != SSH_CHANNEL_OPEN)
Damien Miller34132e52000-01-14 15:45:46 +11001608 continue;
Damien Miller34132e52000-01-14 15:45:46 +11001609 }
Damien Millerefb4afe2000-04-12 18:45:05 +10001610 if (compat20 &&
1611 (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001612 /* XXX is this true? */
Ben Lindstromb1131e92001-03-05 07:27:13 +00001613 debug2("channel %d: no data after CLOSE", c->self);
Damien Miller33b13562000-04-04 14:38:59 +10001614 continue;
1615 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001616
Damien Miller95def091999-11-25 00:26:21 +11001617 /* Get the amount of buffered data for this channel. */
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001618 if ((c->istate == CHAN_INPUT_OPEN ||
1619 c->istate == CHAN_INPUT_WAIT_DRAIN) &&
1620 (len = buffer_len(&c->input)) > 0) {
Ben Lindstrome9c99912001-06-09 00:41:05 +00001621 /*
1622 * Send some data for the other side over the secure
1623 * connection.
1624 */
Damien Miller33b13562000-04-04 14:38:59 +10001625 if (compat20) {
1626 if (len > c->remote_window)
1627 len = c->remote_window;
1628 if (len > c->remote_maxpacket)
1629 len = c->remote_maxpacket;
Damien Miller95def091999-11-25 00:26:21 +11001630 } else {
Damien Miller33b13562000-04-04 14:38:59 +10001631 if (packet_is_interactive()) {
1632 if (len > 1024)
1633 len = 512;
1634 } else {
1635 /* Keep the packets at reasonable size. */
1636 if (len > packet_get_maxsize()/2)
1637 len = packet_get_maxsize()/2;
1638 }
Damien Miller95def091999-11-25 00:26:21 +11001639 }
Damien Millerb38eff82000-04-01 11:09:21 +10001640 if (len > 0) {
Damien Miller33b13562000-04-04 14:38:59 +10001641 packet_start(compat20 ?
1642 SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
Damien Millerb38eff82000-04-01 11:09:21 +10001643 packet_put_int(c->remote_id);
1644 packet_put_string(buffer_ptr(&c->input), len);
1645 packet_send();
1646 buffer_consume(&c->input, len);
1647 c->remote_window -= len;
Damien Millerb38eff82000-04-01 11:09:21 +10001648 }
1649 } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
Damien Miller95def091999-11-25 00:26:21 +11001650 if (compat13)
1651 fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
Damien Miller5428f641999-11-25 11:54:57 +11001652 /*
1653 * input-buffer is empty and read-socket shutdown:
1654 * tell peer, that we will not send more data: send IEOF
1655 */
Damien Millerb38eff82000-04-01 11:09:21 +10001656 chan_ibuf_empty(c);
Damien Miller95def091999-11-25 00:26:21 +11001657 }
Damien Miller33b13562000-04-04 14:38:59 +10001658 /* Send extended data, i.e. stderr */
1659 if (compat20 &&
1660 c->remote_window > 0 &&
1661 (len = buffer_len(&c->extended)) > 0 &&
1662 c->extended_usage == CHAN_EXTENDED_READ) {
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001663 debug2("channel %d: rwin %d elen %d euse %d",
1664 c->self, c->remote_window, buffer_len(&c->extended),
1665 c->extended_usage);
Damien Miller33b13562000-04-04 14:38:59 +10001666 if (len > c->remote_window)
1667 len = c->remote_window;
1668 if (len > c->remote_maxpacket)
1669 len = c->remote_maxpacket;
1670 packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
1671 packet_put_int(c->remote_id);
1672 packet_put_int(SSH2_EXTENDED_DATA_STDERR);
1673 packet_put_string(buffer_ptr(&c->extended), len);
1674 packet_send();
1675 buffer_consume(&c->extended, len);
1676 c->remote_window -= len;
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001677 debug2("channel %d: sent ext data %d", c->self, len);
Damien Miller33b13562000-04-04 14:38:59 +10001678 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001679 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001680}
1681
Ben Lindstrome9c99912001-06-09 00:41:05 +00001682
1683/* -- protocol input */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001684
Damien Miller4af51302000-04-16 11:18:38 +10001685void
Damien Miller62cee002000-09-23 17:15:56 +11001686channel_input_data(int type, int plen, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001687{
Damien Miller34132e52000-01-14 15:45:46 +11001688 int id;
Damien Miller95def091999-11-25 00:26:21 +11001689 char *data;
Ben Lindstrom46c16222000-12-22 01:43:59 +00001690 u_int data_len;
Damien Millerb38eff82000-04-01 11:09:21 +10001691 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001692
Damien Miller95def091999-11-25 00:26:21 +11001693 /* Get the channel number and verify it. */
Damien Miller34132e52000-01-14 15:45:46 +11001694 id = packet_get_int();
Damien Millerb38eff82000-04-01 11:09:21 +10001695 c = channel_lookup(id);
1696 if (c == NULL)
Damien Miller34132e52000-01-14 15:45:46 +11001697 packet_disconnect("Received data for nonexistent channel %d.", id);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001698
Damien Miller95def091999-11-25 00:26:21 +11001699 /* Ignore any data for non-open channels (might happen on close) */
Damien Millerb38eff82000-04-01 11:09:21 +10001700 if (c->type != SSH_CHANNEL_OPEN &&
1701 c->type != SSH_CHANNEL_X11_OPEN)
Damien Miller34132e52000-01-14 15:45:46 +11001702 return;
1703
1704 /* same for protocol 1.5 if output end is no longer open */
Damien Millerb38eff82000-04-01 11:09:21 +10001705 if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN)
Damien Miller95def091999-11-25 00:26:21 +11001706 return;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001707
Damien Miller95def091999-11-25 00:26:21 +11001708 /* Get the data. */
1709 data = packet_get_string(&data_len);
Damien Miller4af51302000-04-16 11:18:38 +10001710 packet_done();
Damien Millerb38eff82000-04-01 11:09:21 +10001711
Damien Miller33b13562000-04-04 14:38:59 +10001712 if (compat20){
1713 if (data_len > c->local_maxpacket) {
1714 log("channel %d: rcvd big packet %d, maxpack %d",
1715 c->self, data_len, c->local_maxpacket);
1716 }
1717 if (data_len > c->local_window) {
1718 log("channel %d: rcvd too much data %d, win %d",
1719 c->self, data_len, c->local_window);
1720 xfree(data);
1721 return;
1722 }
1723 c->local_window -= data_len;
1724 }else{
1725 packet_integrity_check(plen, 4 + 4 + data_len, type);
1726 }
Damien Millerb38eff82000-04-01 11:09:21 +10001727 buffer_append(&c->output, data, data_len);
Damien Miller95def091999-11-25 00:26:21 +11001728 xfree(data);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001729}
Ben Lindstrome9c99912001-06-09 00:41:05 +00001730
Damien Miller4af51302000-04-16 11:18:38 +10001731void
Damien Miller62cee002000-09-23 17:15:56 +11001732channel_input_extended_data(int type, int plen, void *ctxt)
Damien Miller33b13562000-04-04 14:38:59 +10001733{
1734 int id;
1735 int tcode;
1736 char *data;
Ben Lindstrom46c16222000-12-22 01:43:59 +00001737 u_int data_len;
Damien Miller33b13562000-04-04 14:38:59 +10001738 Channel *c;
1739
1740 /* Get the channel number and verify it. */
1741 id = packet_get_int();
1742 c = channel_lookup(id);
1743
1744 if (c == NULL)
1745 packet_disconnect("Received extended_data for bad channel %d.", id);
1746 if (c->type != SSH_CHANNEL_OPEN) {
1747 log("channel %d: ext data for non open", id);
1748 return;
1749 }
1750 tcode = packet_get_int();
1751 if (c->efd == -1 ||
1752 c->extended_usage != CHAN_EXTENDED_WRITE ||
1753 tcode != SSH2_EXTENDED_DATA_STDERR) {
1754 log("channel %d: bad ext data", c->self);
1755 return;
1756 }
1757 data = packet_get_string(&data_len);
Damien Miller4af51302000-04-16 11:18:38 +10001758 packet_done();
Damien Miller33b13562000-04-04 14:38:59 +10001759 if (data_len > c->local_window) {
1760 log("channel %d: rcvd too much extended_data %d, win %d",
1761 c->self, data_len, c->local_window);
1762 xfree(data);
1763 return;
1764 }
Damien Millerd3444942000-09-30 14:20:03 +11001765 debug2("channel %d: rcvd ext data %d", c->self, data_len);
Damien Miller33b13562000-04-04 14:38:59 +10001766 c->local_window -= data_len;
1767 buffer_append(&c->extended, data, data_len);
1768 xfree(data);
1769}
1770
Damien Miller4af51302000-04-16 11:18:38 +10001771void
Damien Miller62cee002000-09-23 17:15:56 +11001772channel_input_ieof(int type, int plen, void *ctxt)
Damien Millerb38eff82000-04-01 11:09:21 +10001773{
1774 int id;
1775 Channel *c;
1776
1777 packet_integrity_check(plen, 4, type);
1778
1779 id = packet_get_int();
1780 c = channel_lookup(id);
1781 if (c == NULL)
1782 packet_disconnect("Received ieof for nonexistent channel %d.", id);
1783 chan_rcvd_ieof(c);
1784}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001785
Damien Miller4af51302000-04-16 11:18:38 +10001786void
Damien Miller62cee002000-09-23 17:15:56 +11001787channel_input_close(int type, int plen, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001788{
Damien Millerb38eff82000-04-01 11:09:21 +10001789 int id;
1790 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001791
Damien Millerb38eff82000-04-01 11:09:21 +10001792 packet_integrity_check(plen, 4, type);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001793
Damien Millerb38eff82000-04-01 11:09:21 +10001794 id = packet_get_int();
1795 c = channel_lookup(id);
1796 if (c == NULL)
1797 packet_disconnect("Received close for nonexistent channel %d.", id);
Damien Miller5428f641999-11-25 11:54:57 +11001798
1799 /*
1800 * Send a confirmation that we have closed the channel and no more
1801 * data is coming for it.
1802 */
Damien Miller95def091999-11-25 00:26:21 +11001803 packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
Damien Millerb38eff82000-04-01 11:09:21 +10001804 packet_put_int(c->remote_id);
Damien Miller95def091999-11-25 00:26:21 +11001805 packet_send();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001806
Damien Miller5428f641999-11-25 11:54:57 +11001807 /*
1808 * If the channel is in closed state, we have sent a close request,
1809 * and the other side will eventually respond with a confirmation.
1810 * Thus, we cannot free the channel here, because then there would be
1811 * no-one to receive the confirmation. The channel gets freed when
1812 * the confirmation arrives.
1813 */
Damien Millerb38eff82000-04-01 11:09:21 +10001814 if (c->type != SSH_CHANNEL_CLOSED) {
Damien Miller5428f641999-11-25 11:54:57 +11001815 /*
1816 * Not a closed channel - mark it as draining, which will
1817 * cause it to be freed later.
1818 */
Damien Millerb38eff82000-04-01 11:09:21 +10001819 buffer_consume(&c->input, buffer_len(&c->input));
1820 c->type = SSH_CHANNEL_OUTPUT_DRAINING;
Damien Miller95def091999-11-25 00:26:21 +11001821 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001822}
1823
Damien Millerb38eff82000-04-01 11:09:21 +10001824/* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
Damien Miller4af51302000-04-16 11:18:38 +10001825void
Damien Miller62cee002000-09-23 17:15:56 +11001826channel_input_oclose(int type, int plen, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001827{
Damien Millerb38eff82000-04-01 11:09:21 +10001828 int id = packet_get_int();
1829 Channel *c = channel_lookup(id);
1830 packet_integrity_check(plen, 4, type);
1831 if (c == NULL)
1832 packet_disconnect("Received oclose for nonexistent channel %d.", id);
1833 chan_rcvd_oclose(c);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001834}
1835
Damien Miller4af51302000-04-16 11:18:38 +10001836void
Damien Miller62cee002000-09-23 17:15:56 +11001837channel_input_close_confirmation(int type, int plen, void *ctxt)
Damien Millerb38eff82000-04-01 11:09:21 +10001838{
1839 int id = packet_get_int();
1840 Channel *c = channel_lookup(id);
1841
Damien Miller4af51302000-04-16 11:18:38 +10001842 packet_done();
Damien Millerb38eff82000-04-01 11:09:21 +10001843 if (c == NULL)
1844 packet_disconnect("Received close confirmation for "
1845 "out-of-range channel %d.", id);
1846 if (c->type != SSH_CHANNEL_CLOSED)
1847 packet_disconnect("Received close confirmation for "
1848 "non-closed channel %d (type %d).", id, c->type);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001849 channel_free(c);
Damien Millerb38eff82000-04-01 11:09:21 +10001850}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001851
Damien Miller4af51302000-04-16 11:18:38 +10001852void
Damien Miller62cee002000-09-23 17:15:56 +11001853channel_input_open_confirmation(int type, int plen, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001854{
Damien Millerb38eff82000-04-01 11:09:21 +10001855 int id, remote_id;
1856 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001857
Damien Miller33b13562000-04-04 14:38:59 +10001858 if (!compat20)
1859 packet_integrity_check(plen, 4 + 4, type);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001860
Damien Millerb38eff82000-04-01 11:09:21 +10001861 id = packet_get_int();
1862 c = channel_lookup(id);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001863
Damien Millerb38eff82000-04-01 11:09:21 +10001864 if (c==NULL || c->type != SSH_CHANNEL_OPENING)
1865 packet_disconnect("Received open confirmation for "
1866 "non-opening channel %d.", id);
1867 remote_id = packet_get_int();
Damien Miller5428f641999-11-25 11:54:57 +11001868 /* Record the remote channel number and mark that the channel is now open. */
Damien Millerb38eff82000-04-01 11:09:21 +10001869 c->remote_id = remote_id;
1870 c->type = SSH_CHANNEL_OPEN;
Damien Miller33b13562000-04-04 14:38:59 +10001871
1872 if (compat20) {
1873 c->remote_window = packet_get_int();
1874 c->remote_maxpacket = packet_get_int();
Damien Miller4af51302000-04-16 11:18:38 +10001875 packet_done();
Damien Miller33b13562000-04-04 14:38:59 +10001876 if (c->cb_fn != NULL && c->cb_event == type) {
Damien Millerd3444942000-09-30 14:20:03 +11001877 debug2("callback start");
Damien Miller33b13562000-04-04 14:38:59 +10001878 c->cb_fn(c->self, c->cb_arg);
Damien Millerd3444942000-09-30 14:20:03 +11001879 debug2("callback done");
Damien Miller33b13562000-04-04 14:38:59 +10001880 }
1881 debug("channel %d: open confirm rwindow %d rmax %d", c->self,
1882 c->remote_window, c->remote_maxpacket);
1883 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001884}
1885
Ben Lindstrombba81212001-06-25 05:01:22 +00001886static char *
Ben Lindstrom69128662001-05-08 20:07:39 +00001887reason2txt(int reason)
1888{
1889 switch(reason) {
1890 case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
1891 return "administratively prohibited";
1892 case SSH2_OPEN_CONNECT_FAILED:
1893 return "connect failed";
1894 case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
1895 return "unknown channel type";
1896 case SSH2_OPEN_RESOURCE_SHORTAGE:
1897 return "resource shortage";
1898 }
Ben Lindstrome2595442001-06-05 20:01:39 +00001899 return "unknown reason";
Ben Lindstrom69128662001-05-08 20:07:39 +00001900}
1901
Damien Miller4af51302000-04-16 11:18:38 +10001902void
Damien Miller62cee002000-09-23 17:15:56 +11001903channel_input_open_failure(int type, int plen, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001904{
Kevin Steves12057502001-02-05 14:54:34 +00001905 int id, reason;
1906 char *msg = NULL, *lang = NULL;
Damien Millerb38eff82000-04-01 11:09:21 +10001907 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001908
Damien Miller33b13562000-04-04 14:38:59 +10001909 if (!compat20)
1910 packet_integrity_check(plen, 4, type);
Damien Millerb38eff82000-04-01 11:09:21 +10001911
1912 id = packet_get_int();
1913 c = channel_lookup(id);
1914
1915 if (c==NULL || c->type != SSH_CHANNEL_OPENING)
1916 packet_disconnect("Received open failure for "
1917 "non-opening channel %d.", id);
Damien Miller33b13562000-04-04 14:38:59 +10001918 if (compat20) {
Kevin Steves12057502001-02-05 14:54:34 +00001919 reason = packet_get_int();
Ben Lindstromf3436742001-04-29 19:52:00 +00001920 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
Kevin Steves12057502001-02-05 14:54:34 +00001921 msg = packet_get_string(NULL);
1922 lang = packet_get_string(NULL);
1923 }
Damien Miller4af51302000-04-16 11:18:38 +10001924 packet_done();
Ben Lindstrom69128662001-05-08 20:07:39 +00001925 log("channel %d: open failed: %s%s%s", id,
1926 reason2txt(reason), msg ? ": ": "", msg ? msg : "");
Kevin Steves12057502001-02-05 14:54:34 +00001927 if (msg != NULL)
1928 xfree(msg);
1929 if (lang != NULL)
1930 xfree(lang);
Damien Miller33b13562000-04-04 14:38:59 +10001931 }
Damien Miller95def091999-11-25 00:26:21 +11001932 /* Free the channel. This will also close the socket. */
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001933 channel_free(c);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001934}
1935
Damien Miller33b13562000-04-04 14:38:59 +10001936void
Damien Miller62cee002000-09-23 17:15:56 +11001937channel_input_channel_request(int type, int plen, void *ctxt)
Damien Miller33b13562000-04-04 14:38:59 +10001938{
1939 int id;
1940 Channel *c;
1941
1942 id = packet_get_int();
1943 c = channel_lookup(id);
1944
1945 if (c == NULL ||
1946 (c->type != SSH_CHANNEL_OPEN && c->type != SSH_CHANNEL_LARVAL))
1947 packet_disconnect("Received request for "
1948 "non-open channel %d.", id);
1949 if (c->cb_fn != NULL && c->cb_event == type) {
Damien Millerd3444942000-09-30 14:20:03 +11001950 debug2("callback start");
Damien Miller33b13562000-04-04 14:38:59 +10001951 c->cb_fn(c->self, c->cb_arg);
Damien Millerd3444942000-09-30 14:20:03 +11001952 debug2("callback done");
Damien Miller33b13562000-04-04 14:38:59 +10001953 } else {
1954 char *service = packet_get_string(NULL);
Ben Lindstromcc74df72001-03-05 06:20:14 +00001955 debug("channel %d: rcvd request for %s", c->self, service);
Damien Millerd3444942000-09-30 14:20:03 +11001956 debug("cb_fn %p cb_event %d", c->cb_fn , c->cb_event);
Damien Miller33b13562000-04-04 14:38:59 +10001957 xfree(service);
1958 }
1959}
1960
Damien Miller4af51302000-04-16 11:18:38 +10001961void
Damien Miller62cee002000-09-23 17:15:56 +11001962channel_input_window_adjust(int type, int plen, void *ctxt)
Damien Miller33b13562000-04-04 14:38:59 +10001963{
1964 Channel *c;
1965 int id, adjust;
1966
1967 if (!compat20)
1968 return;
1969
1970 /* Get the channel number and verify it. */
1971 id = packet_get_int();
1972 c = channel_lookup(id);
1973
1974 if (c == NULL || c->type != SSH_CHANNEL_OPEN) {
1975 log("Received window adjust for "
1976 "non-open channel %d.", id);
1977 return;
1978 }
1979 adjust = packet_get_int();
Damien Miller4af51302000-04-16 11:18:38 +10001980 packet_done();
Damien Millerd3444942000-09-30 14:20:03 +11001981 debug2("channel %d: rcvd adjust %d", id, adjust);
Damien Miller33b13562000-04-04 14:38:59 +10001982 c->remote_window += adjust;
1983}
1984
Damien Miller4af51302000-04-16 11:18:38 +10001985void
Ben Lindstrome9c99912001-06-09 00:41:05 +00001986channel_input_port_open(int type, int plen, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001987{
Ben Lindstrome9c99912001-06-09 00:41:05 +00001988 Channel *c = NULL;
1989 u_short host_port;
1990 char *host, *originator_string;
1991 int remote_id, sock = -1;
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001992
Ben Lindstrome9c99912001-06-09 00:41:05 +00001993 remote_id = packet_get_int();
1994 host = packet_get_string(NULL);
1995 host_port = packet_get_int();
1996
1997 if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
1998 originator_string = packet_get_string(NULL);
1999 } else {
2000 originator_string = xstrdup("unknown (remote did not supply name)");
2001 }
2002 packet_done();
2003 sock = channel_connect_to(host, host_port);
2004 if (sock != -1) {
2005 c = channel_new("connected socket",
2006 SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0,
2007 originator_string, 1);
2008 if (c == NULL) {
2009 error("channel_input_port_open: channel_new failed");
2010 close(sock);
2011 } else {
2012 c->remote_id = remote_id;
Damien Miller95def091999-11-25 00:26:21 +11002013 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002014 }
Ben Lindstrome9c99912001-06-09 00:41:05 +00002015 if (c == NULL) {
2016 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2017 packet_put_int(remote_id);
2018 packet_send();
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002019 }
Ben Lindstrome9c99912001-06-09 00:41:05 +00002020 xfree(host);
Ben Lindstrom5744dc42001-04-13 23:28:01 +00002021}
2022
2023
Ben Lindstrome9c99912001-06-09 00:41:05 +00002024/* -- tcp forwarding */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002025
Damien Miller5428f641999-11-25 11:54:57 +11002026/*
2027 * Initiate forwarding of connections to local port "port" through the secure
2028 * channel to host:port from remote side.
2029 */
Kevin Steves12057502001-02-05 14:54:34 +00002030int
Damien Miller0bc1bd82000-11-13 22:57:25 +11002031channel_request_local_forwarding(u_short listen_port, const char *host_to_connect,
2032 u_short port_to_connect, int gateway_ports)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002033{
Kevin Steves12057502001-02-05 14:54:34 +00002034 return channel_request_forwarding(
Damien Miller0bc1bd82000-11-13 22:57:25 +11002035 NULL, listen_port,
2036 host_to_connect, port_to_connect,
2037 gateway_ports, /*remote_fwd*/ 0);
2038}
2039
2040/*
2041 * If 'remote_fwd' is true we have a '-R style' listener for protocol 2
2042 * (SSH_CHANNEL_RPORT_LISTENER).
2043 */
Kevin Steves12057502001-02-05 14:54:34 +00002044int
Damien Miller0bc1bd82000-11-13 22:57:25 +11002045channel_request_forwarding(
2046 const char *listen_address, u_short listen_port,
2047 const char *host_to_connect, u_short port_to_connect,
2048 int gateway_ports, int remote_fwd)
2049{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002050 Channel *c;
Ben Lindstrome9c99912001-06-09 00:41:05 +00002051 int success, sock, on = 1, type;
Damien Miller34132e52000-01-14 15:45:46 +11002052 struct addrinfo hints, *ai, *aitop;
2053 char ntop[NI_MAXHOST], strport[NI_MAXSERV];
Damien Miller0bc1bd82000-11-13 22:57:25 +11002054 const char *host;
Damien Miller5428f641999-11-25 11:54:57 +11002055 struct linger linger;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002056
Kevin Steves12057502001-02-05 14:54:34 +00002057 success = 0;
2058
Damien Miller0bc1bd82000-11-13 22:57:25 +11002059 if (remote_fwd) {
2060 host = listen_address;
Ben Lindstrome9c99912001-06-09 00:41:05 +00002061 type = SSH_CHANNEL_RPORT_LISTENER;
Damien Miller0bc1bd82000-11-13 22:57:25 +11002062 } else {
2063 host = host_to_connect;
Ben Lindstrome9c99912001-06-09 00:41:05 +00002064 type = SSH_CHANNEL_PORT_LISTENER;
Damien Miller0bc1bd82000-11-13 22:57:25 +11002065 }
2066
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002067 if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) {
Kevin Steves12057502001-02-05 14:54:34 +00002068 error("Forward host name too long.");
2069 return success;
2070 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002071
Damien Miller0bc1bd82000-11-13 22:57:25 +11002072 /* XXX listen_address is currently ignored */
Damien Miller5428f641999-11-25 11:54:57 +11002073 /*
Damien Miller34132e52000-01-14 15:45:46 +11002074 * getaddrinfo returns a loopback address if the hostname is
2075 * set to NULL and hints.ai_flags is not AI_PASSIVE
Damien Miller5428f641999-11-25 11:54:57 +11002076 */
Damien Miller34132e52000-01-14 15:45:46 +11002077 memset(&hints, 0, sizeof(hints));
2078 hints.ai_family = IPv4or6;
2079 hints.ai_flags = gateway_ports ? AI_PASSIVE : 0;
2080 hints.ai_socktype = SOCK_STREAM;
Damien Miller0bc1bd82000-11-13 22:57:25 +11002081 snprintf(strport, sizeof strport, "%d", listen_port);
Damien Miller34132e52000-01-14 15:45:46 +11002082 if (getaddrinfo(NULL, strport, &hints, &aitop) != 0)
2083 packet_disconnect("getaddrinfo: fatal error");
Damien Miller5428f641999-11-25 11:54:57 +11002084
Damien Miller34132e52000-01-14 15:45:46 +11002085 for (ai = aitop; ai; ai = ai->ai_next) {
2086 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2087 continue;
2088 if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2089 strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
Damien Miller0bc1bd82000-11-13 22:57:25 +11002090 error("channel_request_forwarding: getnameinfo failed");
Damien Miller34132e52000-01-14 15:45:46 +11002091 continue;
2092 }
2093 /* Create a port to listen for the host. */
2094 sock = socket(ai->ai_family, SOCK_STREAM, 0);
2095 if (sock < 0) {
2096 /* this is no error since kernel may not support ipv6 */
2097 verbose("socket: %.100s", strerror(errno));
2098 continue;
2099 }
2100 /*
2101 * Set socket options. We would like the socket to disappear
2102 * as soon as it has been closed for whatever reason.
2103 */
2104 setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on));
2105 linger.l_onoff = 1;
2106 linger.l_linger = 5;
2107 setsockopt(sock, SOL_SOCKET, SO_LINGER, (void *)&linger, sizeof(linger));
2108 debug("Local forwarding listening on %s port %s.", ntop, strport);
Damien Miller95def091999-11-25 00:26:21 +11002109
Damien Miller34132e52000-01-14 15:45:46 +11002110 /* Bind the socket to the address. */
2111 if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2112 /* address can be in use ipv6 address is already bound */
Damien Miller3c7eeb22000-03-03 22:35:33 +11002113 if (!ai->ai_next)
2114 error("bind: %.100s", strerror(errno));
2115 else
2116 verbose("bind: %.100s", strerror(errno));
Kevin Stevesef4eea92001-02-05 12:42:17 +00002117
Damien Miller34132e52000-01-14 15:45:46 +11002118 close(sock);
2119 continue;
2120 }
2121 /* Start listening for connections on the socket. */
2122 if (listen(sock, 5) < 0) {
2123 error("listen: %.100s", strerror(errno));
2124 close(sock);
2125 continue;
2126 }
2127 /* Allocate a channel number for the socket. */
Ben Lindstrome9c99912001-06-09 00:41:05 +00002128 c = channel_new("port listener", type, sock, sock, -1,
Damien Millerbd483e72000-04-30 10:00:53 +10002129 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
Damien Miller69b69aa2000-10-28 14:19:58 +11002130 0, xstrdup("port listener"), 1);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002131 if (c == NULL) {
2132 error("channel_request_forwarding: channel_new failed");
2133 close(sock);
2134 continue;
2135 }
2136 strlcpy(c->path, host, sizeof(c->path));
2137 c->host_port = port_to_connect;
2138 c->listening_port = listen_port;
Damien Miller34132e52000-01-14 15:45:46 +11002139 success = 1;
2140 }
2141 if (success == 0)
Kevin Steves12057502001-02-05 14:54:34 +00002142 error("channel_request_forwarding: cannot listen to port: %d",
2143 listen_port);
Damien Miller34132e52000-01-14 15:45:46 +11002144 freeaddrinfo(aitop);
Kevin Steves12057502001-02-05 14:54:34 +00002145 return success;
Damien Miller95def091999-11-25 00:26:21 +11002146}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002147
Damien Miller5428f641999-11-25 11:54:57 +11002148/*
2149 * Initiate forwarding of connections to port "port" on remote host through
2150 * the secure channel to host:port from local side.
2151 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002152
Damien Miller4af51302000-04-16 11:18:38 +10002153void
Damien Miller0bc1bd82000-11-13 22:57:25 +11002154channel_request_remote_forwarding(u_short listen_port,
2155 const char *host_to_connect, u_short port_to_connect)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002156{
Damien Miller0bc1bd82000-11-13 22:57:25 +11002157 int payload_len, type, success = 0;
2158
Damien Miller95def091999-11-25 00:26:21 +11002159 /* Record locally that connection to this host/port is permitted. */
2160 if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2161 fatal("channel_request_remote_forwarding: too many forwards");
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002162
Damien Miller95def091999-11-25 00:26:21 +11002163 /* Send the forward request to the remote side. */
Damien Miller33b13562000-04-04 14:38:59 +10002164 if (compat20) {
2165 const char *address_to_bind = "0.0.0.0";
2166 packet_start(SSH2_MSG_GLOBAL_REQUEST);
2167 packet_put_cstring("tcpip-forward");
2168 packet_put_char(0); /* boolean: want reply */
2169 packet_put_cstring(address_to_bind);
2170 packet_put_int(listen_port);
Damien Miller0bc1bd82000-11-13 22:57:25 +11002171 packet_send();
2172 packet_write_wait();
2173 /* Assume that server accepts the request */
2174 success = 1;
Damien Miller33b13562000-04-04 14:38:59 +10002175 } else {
2176 packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
Damien Miller33b13562000-04-04 14:38:59 +10002177 packet_put_int(listen_port);
Damien Miller8bb73be2000-04-19 16:26:12 +10002178 packet_put_cstring(host_to_connect);
2179 packet_put_int(port_to_connect);
Damien Miller33b13562000-04-04 14:38:59 +10002180 packet_send();
2181 packet_write_wait();
Damien Miller0bc1bd82000-11-13 22:57:25 +11002182
2183 /* Wait for response from the remote side. */
2184 type = packet_read(&payload_len);
2185 switch (type) {
2186 case SSH_SMSG_SUCCESS:
2187 success = 1;
2188 break;
2189 case SSH_SMSG_FAILURE:
2190 log("Warning: Server denied remote port forwarding.");
2191 break;
2192 default:
2193 /* Unknown packet */
2194 packet_disconnect("Protocol error for port forward request:"
2195 "received packet type %d.", type);
2196 }
2197 }
2198 if (success) {
2199 permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
2200 permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
2201 permitted_opens[num_permitted_opens].listen_port = listen_port;
2202 num_permitted_opens++;
Damien Miller33b13562000-04-04 14:38:59 +10002203 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002204}
2205
Damien Miller5428f641999-11-25 11:54:57 +11002206/*
2207 * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
2208 * listening for the port, and sends back a success reply (or disconnect
2209 * message if there was an error). This never returns if there was an error.
2210 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002211
Damien Miller4af51302000-04-16 11:18:38 +10002212void
Damien Millere247cc42000-05-07 12:03:14 +10002213channel_input_port_forward_request(int is_root, int gateway_ports)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002214{
Damien Milleraae6c611999-12-06 11:47:28 +11002215 u_short port, host_port;
Damien Miller95def091999-11-25 00:26:21 +11002216 char *hostname;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002217
Damien Miller95def091999-11-25 00:26:21 +11002218 /* Get arguments from the packet. */
2219 port = packet_get_int();
2220 hostname = packet_get_string(NULL);
2221 host_port = packet_get_int();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002222
Damien Millerbac2d8a2000-09-05 16:13:06 +11002223#ifndef HAVE_CYGWIN
Damien Miller5428f641999-11-25 11:54:57 +11002224 /*
2225 * Check that an unprivileged user is not trying to forward a
2226 * privileged port.
2227 */
Damien Miller95def091999-11-25 00:26:21 +11002228 if (port < IPPORT_RESERVED && !is_root)
2229 packet_disconnect("Requested forwarding of port %d but user is not root.",
2230 port);
Damien Millerbac2d8a2000-09-05 16:13:06 +11002231#endif
Damien Miller0bc1bd82000-11-13 22:57:25 +11002232 /* Initiate forwarding */
Damien Millere247cc42000-05-07 12:03:14 +10002233 channel_request_local_forwarding(port, hostname, host_port, gateway_ports);
Damien Miller95def091999-11-25 00:26:21 +11002234
2235 /* Free the argument string. */
2236 xfree(hostname);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002237}
2238
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002239/*
2240 * Permits opening to any host/port if permitted_opens[] is empty. This is
2241 * usually called by the server, because the user could connect to any port
2242 * anyway, and the server has no way to know but to trust the client anyway.
2243 */
2244void
2245channel_permit_all_opens()
2246{
2247 if (num_permitted_opens == 0)
2248 all_opens_permitted = 1;
2249}
2250
Ben Lindstroma3700052001-04-05 23:26:32 +00002251void
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002252channel_add_permitted_opens(char *host, int port)
2253{
2254 if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2255 fatal("channel_request_remote_forwarding: too many forwards");
2256 debug("allow port forwarding to host %s port %d", host, port);
2257
2258 permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
2259 permitted_opens[num_permitted_opens].port_to_connect = port;
2260 num_permitted_opens++;
2261
2262 all_opens_permitted = 0;
2263}
2264
Ben Lindstroma3700052001-04-05 23:26:32 +00002265void
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002266channel_clear_permitted_opens(void)
2267{
2268 int i;
2269
2270 for (i = 0; i < num_permitted_opens; i++)
2271 xfree(permitted_opens[i].host_to_connect);
2272 num_permitted_opens = 0;
2273
2274}
2275
2276
2277/* return socket to remote host, port */
Ben Lindstrombba81212001-06-25 05:01:22 +00002278static int
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002279connect_to(const char *host, u_short port)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002280{
Damien Miller34132e52000-01-14 15:45:46 +11002281 struct addrinfo hints, *ai, *aitop;
2282 char ntop[NI_MAXHOST], strport[NI_MAXSERV];
2283 int gaierr;
Damien Millerb38eff82000-04-01 11:09:21 +10002284 int sock = -1;
Damien Miller95def091999-11-25 00:26:21 +11002285
Damien Miller34132e52000-01-14 15:45:46 +11002286 memset(&hints, 0, sizeof(hints));
2287 hints.ai_family = IPv4or6;
2288 hints.ai_socktype = SOCK_STREAM;
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002289 snprintf(strport, sizeof strport, "%d", port);
Damien Miller34132e52000-01-14 15:45:46 +11002290 if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) {
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002291 error("connect_to %.100s: unknown host (%s)", host,
2292 gai_strerror(gaierr));
Damien Millerb38eff82000-04-01 11:09:21 +10002293 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002294 }
Damien Miller34132e52000-01-14 15:45:46 +11002295 for (ai = aitop; ai; ai = ai->ai_next) {
2296 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2297 continue;
2298 if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2299 strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002300 error("connect_to: getnameinfo failed");
Damien Miller34132e52000-01-14 15:45:46 +11002301 continue;
2302 }
Damien Miller34132e52000-01-14 15:45:46 +11002303 sock = socket(ai->ai_family, SOCK_STREAM, 0);
2304 if (sock < 0) {
2305 error("socket: %.100s", strerror(errno));
2306 continue;
2307 }
Ben Lindstrom48bd7c12001-01-09 00:35:42 +00002308 if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0)
Ben Lindstrom7ad97102000-12-06 01:42:49 +00002309 fatal("connect_to: F_SETFL: %s", strerror(errno));
Ben Lindstrom7ad97102000-12-06 01:42:49 +00002310 if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 &&
2311 errno != EINPROGRESS) {
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002312 error("connect_to %.100s port %s: %.100s", ntop, strport,
Damien Miller34132e52000-01-14 15:45:46 +11002313 strerror(errno));
2314 close(sock);
Kevin Stevesef4eea92001-02-05 12:42:17 +00002315 continue; /* fail -- try next */
Damien Miller34132e52000-01-14 15:45:46 +11002316 }
2317 break; /* success */
2318
2319 }
2320 freeaddrinfo(aitop);
Damien Miller34132e52000-01-14 15:45:46 +11002321 if (!ai) {
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002322 error("connect_to %.100s port %d: failed.", host, port);
Damien Millerb38eff82000-04-01 11:09:21 +10002323 return -1;
2324 }
2325 /* success */
2326 return sock;
2327}
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002328
Damien Miller0bc1bd82000-11-13 22:57:25 +11002329int
Ben Lindstrom173e6462001-07-04 05:15:15 +00002330channel_connect_by_listen_address(u_short listen_port)
Damien Miller0bc1bd82000-11-13 22:57:25 +11002331{
2332 int i;
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002333
Damien Miller0bc1bd82000-11-13 22:57:25 +11002334 for (i = 0; i < num_permitted_opens; i++)
2335 if (permitted_opens[i].listen_port == listen_port)
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002336 return connect_to(
Damien Miller0bc1bd82000-11-13 22:57:25 +11002337 permitted_opens[i].host_to_connect,
2338 permitted_opens[i].port_to_connect);
Ben Lindstromc72745a2000-12-02 19:03:54 +00002339 error("WARNING: Server requests forwarding for unknown listen_port %d",
2340 listen_port);
Damien Miller0bc1bd82000-11-13 22:57:25 +11002341 return -1;
2342}
Damien Millerb38eff82000-04-01 11:09:21 +10002343
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002344/* Check if connecting to that port is permitted and connect. */
2345int
2346channel_connect_to(const char *host, u_short port)
2347{
2348 int i, permit;
2349
2350 permit = all_opens_permitted;
2351 if (!permit) {
2352 for (i = 0; i < num_permitted_opens; i++)
2353 if (permitted_opens[i].port_to_connect == port &&
2354 strcmp(permitted_opens[i].host_to_connect, host) == 0)
2355 permit = 1;
2356
2357 }
2358 if (!permit) {
2359 log("Received request to connect to host %.100s port %d, "
2360 "but the request was denied.", host, port);
2361 return -1;
2362 }
2363 return connect_to(host, port);
2364}
2365
Ben Lindstrome9c99912001-06-09 00:41:05 +00002366/* -- X11 forwarding */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002367
Damien Miller5428f641999-11-25 11:54:57 +11002368/*
2369 * Creates an internet domain socket for listening for X11 connections.
2370 * Returns a suitable value for the DISPLAY variable, or NULL if an error
2371 * occurs.
2372 */
Damien Miller95def091999-11-25 00:26:21 +11002373char *
Damien Millera34a28b1999-12-14 10:47:15 +11002374x11_create_display_inet(int screen_number, int x11_display_offset)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002375{
Damien Milleraae6c611999-12-06 11:47:28 +11002376 int display_number, sock;
2377 u_short port;
Damien Miller34132e52000-01-14 15:45:46 +11002378 struct addrinfo hints, *ai, *aitop;
2379 char strport[NI_MAXSERV];
2380 int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
2381 char display[512];
Damien Miller95def091999-11-25 00:26:21 +11002382 char hostname[MAXHOSTNAMELEN];
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002383
Damien Millera34a28b1999-12-14 10:47:15 +11002384 for (display_number = x11_display_offset;
Damien Miller95def091999-11-25 00:26:21 +11002385 display_number < MAX_DISPLAYS;
2386 display_number++) {
2387 port = 6000 + display_number;
Damien Miller34132e52000-01-14 15:45:46 +11002388 memset(&hints, 0, sizeof(hints));
2389 hints.ai_family = IPv4or6;
2390 hints.ai_flags = AI_PASSIVE; /* XXX loopback only ? */
2391 hints.ai_socktype = SOCK_STREAM;
2392 snprintf(strport, sizeof strport, "%d", port);
2393 if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
2394 error("getaddrinfo: %.100s", gai_strerror(gaierr));
Damien Miller95def091999-11-25 00:26:21 +11002395 return NULL;
2396 }
Damien Miller34132e52000-01-14 15:45:46 +11002397 for (ai = aitop; ai; ai = ai->ai_next) {
2398 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2399 continue;
2400 sock = socket(ai->ai_family, SOCK_STREAM, 0);
2401 if (sock < 0) {
Damien Miller89d97962000-10-14 12:37:19 +11002402 if ((errno != EINVAL) && (errno != EAFNOSUPPORT)) {
Damien Millere2192732000-01-17 13:22:55 +11002403 error("socket: %.100s", strerror(errno));
2404 return NULL;
2405 } else {
Damien Millercb5e44a2000-09-29 12:12:36 +11002406 debug("x11_create_display_inet: Socket family %d not supported",
2407 ai->ai_family);
Damien Millere2192732000-01-17 13:22:55 +11002408 continue;
2409 }
Damien Miller34132e52000-01-14 15:45:46 +11002410 }
2411 if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2412 debug("bind port %d: %.100s", port, strerror(errno));
2413 shutdown(sock, SHUT_RDWR);
2414 close(sock);
Damien Miller3c7eeb22000-03-03 22:35:33 +11002415
2416 if (ai->ai_next)
2417 continue;
2418
Damien Miller34132e52000-01-14 15:45:46 +11002419 for (n = 0; n < num_socks; n++) {
2420 shutdown(socks[n], SHUT_RDWR);
2421 close(socks[n]);
2422 }
2423 num_socks = 0;
2424 break;
2425 }
2426 socks[num_socks++] = sock;
Damien Miller7bcb0892000-03-11 20:45:40 +11002427#ifndef DONT_TRY_OTHER_AF
Damien Miller34132e52000-01-14 15:45:46 +11002428 if (num_socks == NUM_SOCKS)
2429 break;
Damien Miller7bcb0892000-03-11 20:45:40 +11002430#else
2431 break;
2432#endif
Damien Miller95def091999-11-25 00:26:21 +11002433 }
Ben Lindstrom87b147f2001-01-25 00:41:12 +00002434 freeaddrinfo(aitop);
Damien Miller34132e52000-01-14 15:45:46 +11002435 if (num_socks > 0)
2436 break;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002437 }
Damien Miller95def091999-11-25 00:26:21 +11002438 if (display_number >= MAX_DISPLAYS) {
2439 error("Failed to allocate internet-domain X11 display socket.");
2440 return NULL;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002441 }
Damien Miller95def091999-11-25 00:26:21 +11002442 /* Start listening for connections on the socket. */
Damien Miller34132e52000-01-14 15:45:46 +11002443 for (n = 0; n < num_socks; n++) {
2444 sock = socks[n];
2445 if (listen(sock, 5) < 0) {
2446 error("listen: %.100s", strerror(errno));
2447 shutdown(sock, SHUT_RDWR);
2448 close(sock);
2449 return NULL;
2450 }
Damien Miller95def091999-11-25 00:26:21 +11002451 }
Damien Miller34132e52000-01-14 15:45:46 +11002452
Damien Miller95def091999-11-25 00:26:21 +11002453 /* Set up a suitable value for the DISPLAY variable. */
2454 if (gethostname(hostname, sizeof(hostname)) < 0)
2455 fatal("gethostname: %.100s", strerror(errno));
Damien Miller76112de1999-12-21 11:18:08 +11002456
2457#ifdef IPADDR_IN_DISPLAY
Kevin Stevesef4eea92001-02-05 12:42:17 +00002458 /*
Damien Miller76112de1999-12-21 11:18:08 +11002459 * HPUX detects the local hostname in the DISPLAY variable and tries
2460 * to set up a shared memory connection to the server, which it
2461 * incorrectly supposes to be local.
2462 *
2463 * The workaround - as used in later $$H and other programs - is
2464 * is to set display to the host's IP address.
2465 */
2466 {
2467 struct hostent *he;
2468 struct in_addr my_addr;
2469
2470 he = gethostbyname(hostname);
2471 if (he == NULL) {
2472 error("[X11-broken-fwd-hostname-workaround] Could not get "
2473 "IP address for hostname %s.", hostname);
2474
2475 packet_send_debug("[X11-broken-fwd-hostname-workaround]"
2476 "Could not get IP address for hostname %s.", hostname);
2477
2478 shutdown(sock, SHUT_RDWR);
2479 close(sock);
2480
2481 return NULL;
2482 }
2483
2484 memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr));
2485
2486 /* Set DISPLAY to <ip address>:screen.display */
Kevin Stevesef4eea92001-02-05 12:42:17 +00002487 snprintf(display, sizeof(display), "%.50s:%d.%d", inet_ntoa(my_addr),
Kevin Stevesda6cd592000-12-29 18:41:21 +00002488 display_number, screen_number);
Damien Miller76112de1999-12-21 11:18:08 +11002489 }
2490#else /* IPADDR_IN_DISPLAY */
2491 /* Just set DISPLAY to hostname:screen.display */
Damien Miller34132e52000-01-14 15:45:46 +11002492 snprintf(display, sizeof display, "%.400s:%d.%d", hostname,
Kevin Stevesda6cd592000-12-29 18:41:21 +00002493 display_number, screen_number);
Damien Miller76112de1999-12-21 11:18:08 +11002494#endif /* IPADDR_IN_DISPLAY */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002495
Damien Miller34132e52000-01-14 15:45:46 +11002496 /* Allocate a channel for each socket. */
2497 for (n = 0; n < num_socks; n++) {
2498 sock = socks[n];
Damien Millerbd483e72000-04-30 10:00:53 +10002499 (void) channel_new("x11 listener",
2500 SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
2501 CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
Damien Miller69b69aa2000-10-28 14:19:58 +11002502 0, xstrdup("X11 inet listener"), 1);
Damien Miller34132e52000-01-14 15:45:46 +11002503 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002504
Damien Miller95def091999-11-25 00:26:21 +11002505 /* Return a suitable value for the DISPLAY environment variable. */
Damien Miller34132e52000-01-14 15:45:46 +11002506 return xstrdup(display);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002507}
2508
2509#ifndef X_UNIX_PATH
2510#define X_UNIX_PATH "/tmp/.X11-unix/X"
2511#endif
2512
Ben Lindstrombba81212001-06-25 05:01:22 +00002513static int
Ben Lindstrom46c16222000-12-22 01:43:59 +00002514connect_local_xsocket(u_int dnr)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002515{
Damien Miller95def091999-11-25 00:26:21 +11002516 static const char *const x_sockets[] = {
2517 X_UNIX_PATH "%u",
2518 "/var/X/.X11-unix/X" "%u",
2519 "/usr/spool/sockets/X11/" "%u",
2520 NULL
2521 };
2522 int sock;
2523 struct sockaddr_un addr;
2524 const char *const * path;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002525
Damien Miller95def091999-11-25 00:26:21 +11002526 for (path = x_sockets; *path; ++path) {
2527 sock = socket(AF_UNIX, SOCK_STREAM, 0);
2528 if (sock < 0)
2529 error("socket: %.100s", strerror(errno));
2530 memset(&addr, 0, sizeof(addr));
2531 addr.sun_family = AF_UNIX;
2532 snprintf(addr.sun_path, sizeof addr.sun_path, *path, dnr);
2533 if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0)
2534 return sock;
2535 close(sock);
2536 }
2537 error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
2538 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002539}
2540
Damien Millerbd483e72000-04-30 10:00:53 +10002541int
2542x11_connect_display(void)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002543{
Damien Millerbd483e72000-04-30 10:00:53 +10002544 int display_number, sock = 0;
Damien Miller95def091999-11-25 00:26:21 +11002545 const char *display;
Damien Millerbd483e72000-04-30 10:00:53 +10002546 char buf[1024], *cp;
Damien Miller34132e52000-01-14 15:45:46 +11002547 struct addrinfo hints, *ai, *aitop;
2548 char strport[NI_MAXSERV];
2549 int gaierr;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002550
Damien Miller95def091999-11-25 00:26:21 +11002551 /* Try to open a socket for the local X server. */
2552 display = getenv("DISPLAY");
2553 if (!display) {
2554 error("DISPLAY not set.");
Damien Millerbd483e72000-04-30 10:00:53 +10002555 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002556 }
Damien Miller5428f641999-11-25 11:54:57 +11002557 /*
2558 * Now we decode the value of the DISPLAY variable and make a
2559 * connection to the real X server.
2560 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002561
Damien Miller5428f641999-11-25 11:54:57 +11002562 /*
2563 * Check if it is a unix domain socket. Unix domain displays are in
2564 * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
2565 */
Damien Miller95def091999-11-25 00:26:21 +11002566 if (strncmp(display, "unix:", 5) == 0 ||
2567 display[0] == ':') {
2568 /* Connect to the unix domain socket. */
2569 if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) {
2570 error("Could not parse display number from DISPLAY: %.100s",
2571 display);
Damien Millerbd483e72000-04-30 10:00:53 +10002572 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002573 }
2574 /* Create a socket. */
2575 sock = connect_local_xsocket(display_number);
2576 if (sock < 0)
Damien Millerbd483e72000-04-30 10:00:53 +10002577 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002578
2579 /* OK, we now have a connection to the display. */
Damien Millerbd483e72000-04-30 10:00:53 +10002580 return sock;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002581 }
Damien Miller5428f641999-11-25 11:54:57 +11002582 /*
2583 * Connect to an inet socket. The DISPLAY value is supposedly
2584 * hostname:d[.s], where hostname may also be numeric IP address.
2585 */
Damien Miller95def091999-11-25 00:26:21 +11002586 strncpy(buf, display, sizeof(buf));
2587 buf[sizeof(buf) - 1] = 0;
2588 cp = strchr(buf, ':');
2589 if (!cp) {
2590 error("Could not find ':' in DISPLAY: %.100s", display);
Damien Millerbd483e72000-04-30 10:00:53 +10002591 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002592 }
Damien Miller95def091999-11-25 00:26:21 +11002593 *cp = 0;
Damien Miller5428f641999-11-25 11:54:57 +11002594 /* buf now contains the host name. But first we parse the display number. */
Damien Miller95def091999-11-25 00:26:21 +11002595 if (sscanf(cp + 1, "%d", &display_number) != 1) {
2596 error("Could not parse display number from DISPLAY: %.100s",
2597 display);
Damien Millerbd483e72000-04-30 10:00:53 +10002598 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002599 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002600
Damien Miller34132e52000-01-14 15:45:46 +11002601 /* Look up the host address */
2602 memset(&hints, 0, sizeof(hints));
2603 hints.ai_family = IPv4or6;
2604 hints.ai_socktype = SOCK_STREAM;
2605 snprintf(strport, sizeof strport, "%d", 6000 + display_number);
2606 if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
2607 error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr));
Damien Millerbd483e72000-04-30 10:00:53 +10002608 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002609 }
Damien Miller34132e52000-01-14 15:45:46 +11002610 for (ai = aitop; ai; ai = ai->ai_next) {
2611 /* Create a socket. */
2612 sock = socket(ai->ai_family, SOCK_STREAM, 0);
2613 if (sock < 0) {
2614 debug("socket: %.100s", strerror(errno));
Damien Millerb38eff82000-04-01 11:09:21 +10002615 continue;
2616 }
2617 /* Connect it to the display. */
2618 if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2619 debug("connect %.100s port %d: %.100s", buf,
2620 6000 + display_number, strerror(errno));
2621 close(sock);
2622 continue;
2623 }
2624 /* Success */
2625 break;
Damien Miller34132e52000-01-14 15:45:46 +11002626 }
Damien Miller34132e52000-01-14 15:45:46 +11002627 freeaddrinfo(aitop);
2628 if (!ai) {
Damien Miller4af51302000-04-16 11:18:38 +10002629 error("connect %.100s port %d: %.100s", buf, 6000 + display_number,
Damien Miller34132e52000-01-14 15:45:46 +11002630 strerror(errno));
Damien Millerbd483e72000-04-30 10:00:53 +10002631 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002632 }
Damien Millerbd483e72000-04-30 10:00:53 +10002633 return sock;
2634}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002635
Damien Millerbd483e72000-04-30 10:00:53 +10002636/*
2637 * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
2638 * the remote channel number. We should do whatever we want, and respond
2639 * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
2640 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002641
Damien Millerbd483e72000-04-30 10:00:53 +10002642void
Damien Miller62cee002000-09-23 17:15:56 +11002643x11_input_open(int type, int plen, void *ctxt)
Damien Millerbd483e72000-04-30 10:00:53 +10002644{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002645 Channel *c = NULL;
2646 int remote_id, sock = 0;
Damien Millerbd483e72000-04-30 10:00:53 +10002647 char *remote_host;
Damien Millerbd483e72000-04-30 10:00:53 +10002648
2649 debug("Received X11 open request.");
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002650
2651 remote_id = packet_get_int();
Ben Lindstrome9c99912001-06-09 00:41:05 +00002652
2653 if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002654 remote_host = packet_get_string(NULL);
2655 } else {
2656 remote_host = xstrdup("unknown (remote did not supply name)");
2657 }
2658 packet_done();
Damien Millerbd483e72000-04-30 10:00:53 +10002659
2660 /* Obtain a connection to the real X display. */
2661 sock = x11_connect_display();
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002662 if (sock != -1) {
2663 /* Allocate a channel for this connection. */
2664 c = channel_new("connected x11 socket",
2665 SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
2666 remote_host, 1);
2667 if (c == NULL) {
2668 error("x11_input_open: channel_new failed");
2669 close(sock);
2670 } else {
2671 c->remote_id = remote_id;
2672 }
2673 }
2674 if (c == NULL) {
Damien Millerbd483e72000-04-30 10:00:53 +10002675 /* Send refusal to the remote host. */
2676 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002677 packet_put_int(remote_id);
Damien Millerbd483e72000-04-30 10:00:53 +10002678 } else {
Damien Millerbd483e72000-04-30 10:00:53 +10002679 /* Send a confirmation to the remote host. */
2680 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002681 packet_put_int(remote_id);
2682 packet_put_int(c->self);
Damien Millerbd483e72000-04-30 10:00:53 +10002683 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002684 packet_send();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002685}
2686
Damien Miller69b69aa2000-10-28 14:19:58 +11002687/* dummy protocol handler that denies SSH-1 requests (agent/x11) */
2688void
2689deny_input_open(int type, int plen, void *ctxt)
2690{
2691 int rchan = packet_get_int();
2692 switch(type){
2693 case SSH_SMSG_AGENT_OPEN:
2694 error("Warning: ssh server tried agent forwarding.");
2695 break;
2696 case SSH_SMSG_X11_OPEN:
2697 error("Warning: ssh server tried X11 forwarding.");
2698 break;
2699 default:
2700 error("deny_input_open: type %d plen %d", type, plen);
2701 break;
2702 }
2703 error("Warning: this is probably a break in attempt by a malicious server.");
2704 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2705 packet_put_int(rchan);
2706 packet_send();
2707}
2708
Damien Miller5428f641999-11-25 11:54:57 +11002709/*
2710 * Requests forwarding of X11 connections, generates fake authentication
2711 * data, and enables authentication spoofing.
Ben Lindstrome9c99912001-06-09 00:41:05 +00002712 * This should be called in the client only.
Damien Miller5428f641999-11-25 11:54:57 +11002713 */
Damien Miller4af51302000-04-16 11:18:38 +10002714void
Damien Millerbd483e72000-04-30 10:00:53 +10002715x11_request_forwarding_with_spoofing(int client_session_id,
2716 const char *proto, const char *data)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002717{
Ben Lindstrom46c16222000-12-22 01:43:59 +00002718 u_int data_len = (u_int) strlen(data) / 2;
Ben Lindstromb3211a82001-02-10 22:33:19 +00002719 u_int i, value, len;
Damien Miller95def091999-11-25 00:26:21 +11002720 char *new_data;
2721 int screen_number;
2722 const char *cp;
2723 u_int32_t rand = 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002724
Damien Miller95def091999-11-25 00:26:21 +11002725 cp = getenv("DISPLAY");
2726 if (cp)
2727 cp = strchr(cp, ':');
2728 if (cp)
2729 cp = strchr(cp, '.');
2730 if (cp)
2731 screen_number = atoi(cp + 1);
2732 else
2733 screen_number = 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002734
Damien Miller95def091999-11-25 00:26:21 +11002735 /* Save protocol name. */
2736 x11_saved_proto = xstrdup(proto);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002737
Damien Miller5428f641999-11-25 11:54:57 +11002738 /*
2739 * Extract real authentication data and generate fake data of the
2740 * same length.
2741 */
Damien Miller95def091999-11-25 00:26:21 +11002742 x11_saved_data = xmalloc(data_len);
2743 x11_fake_data = xmalloc(data_len);
2744 for (i = 0; i < data_len; i++) {
2745 if (sscanf(data + 2 * i, "%2x", &value) != 1)
2746 fatal("x11_request_forwarding: bad authentication data: %.100s", data);
2747 if (i % 4 == 0)
2748 rand = arc4random();
2749 x11_saved_data[i] = value;
2750 x11_fake_data[i] = rand & 0xff;
2751 rand >>= 8;
2752 }
2753 x11_saved_data_len = data_len;
2754 x11_fake_data_len = data_len;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002755
Damien Miller95def091999-11-25 00:26:21 +11002756 /* Convert the fake data into hex. */
Ben Lindstromb3211a82001-02-10 22:33:19 +00002757 len = 2 * data_len + 1;
2758 new_data = xmalloc(len);
Damien Miller95def091999-11-25 00:26:21 +11002759 for (i = 0; i < data_len; i++)
Ben Lindstromb3211a82001-02-10 22:33:19 +00002760 snprintf(new_data + 2 * i, len - 2 * i,
2761 "%02x", (u_char) x11_fake_data[i]);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002762
Damien Miller95def091999-11-25 00:26:21 +11002763 /* Send the request packet. */
Damien Millerbd483e72000-04-30 10:00:53 +10002764 if (compat20) {
2765 channel_request_start(client_session_id, "x11-req", 0);
2766 packet_put_char(0); /* XXX bool single connection */
2767 } else {
2768 packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
2769 }
2770 packet_put_cstring(proto);
2771 packet_put_cstring(new_data);
Damien Miller95def091999-11-25 00:26:21 +11002772 packet_put_int(screen_number);
2773 packet_send();
2774 packet_write_wait();
2775 xfree(new_data);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002776}
2777
Ben Lindstrome9c99912001-06-09 00:41:05 +00002778
2779/* -- agent forwarding */
2780
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002781/* Sends a message to the server to request authentication fd forwarding. */
2782
Damien Miller4af51302000-04-16 11:18:38 +10002783void
Damien Miller95def091999-11-25 00:26:21 +11002784auth_request_forwarding()
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002785{
Damien Miller95def091999-11-25 00:26:21 +11002786 packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
2787 packet_send();
2788 packet_write_wait();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002789}
2790
Damien Miller5428f641999-11-25 11:54:57 +11002791/*
2792 * Returns the name of the forwarded authentication socket. Returns NULL if
2793 * there is no forwarded authentication socket. The returned value points to
2794 * a static buffer.
2795 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002796
Damien Miller95def091999-11-25 00:26:21 +11002797char *
2798auth_get_socket_name()
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002799{
Ben Lindstrome9c99912001-06-09 00:41:05 +00002800 return auth_sock_name;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002801}
2802
2803/* removes the agent forwarding socket */
2804
Damien Miller4af51302000-04-16 11:18:38 +10002805void
Ben Lindstrom983c0982001-06-09 01:20:06 +00002806auth_sock_cleanup_proc(void *_pw)
Damien Miller95def091999-11-25 00:26:21 +11002807{
Ben Lindstrom983c0982001-06-09 01:20:06 +00002808 struct passwd *pw = _pw;
2809
Ben Lindstrom838394c2001-06-09 01:11:59 +00002810 if (auth_sock_name) {
Ben Lindstrom983c0982001-06-09 01:20:06 +00002811 temporarily_use_uid(pw);
Ben Lindstrom838394c2001-06-09 01:11:59 +00002812 unlink(auth_sock_name);
2813 rmdir(auth_sock_dir);
2814 auth_sock_name = NULL;
Ben Lindstrom983c0982001-06-09 01:20:06 +00002815 restore_uid();
Ben Lindstrom838394c2001-06-09 01:11:59 +00002816 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002817}
2818
Damien Miller5428f641999-11-25 11:54:57 +11002819/*
Damien Millerd3a18572000-06-07 19:55:44 +10002820 * This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server.
Damien Miller5428f641999-11-25 11:54:57 +11002821 * This starts forwarding authentication requests.
2822 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002823
Damien Millerd3a18572000-06-07 19:55:44 +10002824int
Damien Miller95def091999-11-25 00:26:21 +11002825auth_input_request_forwarding(struct passwd * pw)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002826{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002827 Channel *nc;
2828 int sock;
Damien Miller95def091999-11-25 00:26:21 +11002829 struct sockaddr_un sunaddr;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002830
Ben Lindstrome9c99912001-06-09 00:41:05 +00002831 if (auth_get_socket_name() != NULL) {
2832 error("authentication forwarding requested twice.");
2833 return 0;
2834 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002835
Damien Miller95def091999-11-25 00:26:21 +11002836 /* Temporarily drop privileged uid for mkdir/bind. */
Ben Lindstrom3fcf1a22001-04-08 18:26:59 +00002837 temporarily_use_uid(pw);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002838
Damien Miller95def091999-11-25 00:26:21 +11002839 /* Allocate a buffer for the socket name, and format the name. */
Ben Lindstrome9c99912001-06-09 00:41:05 +00002840 auth_sock_name = xmalloc(MAXPATHLEN);
2841 auth_sock_dir = xmalloc(MAXPATHLEN);
2842 strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXX", MAXPATHLEN);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002843
Damien Miller95def091999-11-25 00:26:21 +11002844 /* Create private directory for socket */
Ben Lindstrome9c99912001-06-09 00:41:05 +00002845 if (mkdtemp(auth_sock_dir) == NULL) {
2846 packet_send_debug("Agent forwarding disabled: "
2847 "mkdtemp() failed: %.100s", strerror(errno));
Damien Millerd3a18572000-06-07 19:55:44 +10002848 restore_uid();
Ben Lindstrome9c99912001-06-09 00:41:05 +00002849 xfree(auth_sock_name);
2850 xfree(auth_sock_dir);
2851 auth_sock_name = NULL;
2852 auth_sock_dir = NULL;
Damien Millerd3a18572000-06-07 19:55:44 +10002853 return 0;
2854 }
Ben Lindstrome9c99912001-06-09 00:41:05 +00002855 snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%d",
2856 auth_sock_dir, (int) getpid());
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002857
Ben Lindstrom838394c2001-06-09 01:11:59 +00002858 /* delete agent socket on fatal() */
Ben Lindstrom983c0982001-06-09 01:20:06 +00002859 fatal_add_cleanup(auth_sock_cleanup_proc, pw);
Ben Lindstrom838394c2001-06-09 01:11:59 +00002860
Damien Miller95def091999-11-25 00:26:21 +11002861 /* Create the socket. */
2862 sock = socket(AF_UNIX, SOCK_STREAM, 0);
2863 if (sock < 0)
2864 packet_disconnect("socket: %.100s", strerror(errno));
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002865
Damien Miller95def091999-11-25 00:26:21 +11002866 /* Bind it to the name. */
2867 memset(&sunaddr, 0, sizeof(sunaddr));
2868 sunaddr.sun_family = AF_UNIX;
Ben Lindstrome9c99912001-06-09 00:41:05 +00002869 strncpy(sunaddr.sun_path, auth_sock_name,
Damien Miller95def091999-11-25 00:26:21 +11002870 sizeof(sunaddr.sun_path));
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002871
Damien Miller95def091999-11-25 00:26:21 +11002872 if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0)
2873 packet_disconnect("bind: %.100s", strerror(errno));
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002874
Damien Miller95def091999-11-25 00:26:21 +11002875 /* Restore the privileged uid. */
2876 restore_uid();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002877
Damien Miller95def091999-11-25 00:26:21 +11002878 /* Start listening on the socket. */
2879 if (listen(sock, 5) < 0)
2880 packet_disconnect("listen: %.100s", strerror(errno));
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002881
Damien Miller95def091999-11-25 00:26:21 +11002882 /* Allocate a channel for the authentication agent socket. */
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002883 nc = channel_new("auth socket",
Damien Miller0bc1bd82000-11-13 22:57:25 +11002884 SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1,
2885 CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
2886 0, xstrdup("auth socket"), 1);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002887 if (nc == NULL) {
2888 error("auth_input_request_forwarding: channel_new failed");
Ben Lindstrom983c0982001-06-09 01:20:06 +00002889 auth_sock_cleanup_proc(pw);
Ben Lindstromdf4981b2001-06-09 01:32:29 +00002890 fatal_remove_cleanup(auth_sock_cleanup_proc, pw);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002891 close(sock);
2892 return 0;
2893 }
Ben Lindstrome9c99912001-06-09 00:41:05 +00002894 strlcpy(nc->path, auth_sock_name, sizeof(nc->path));
Damien Millerd3a18572000-06-07 19:55:44 +10002895 return 1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002896}
2897
2898/* This is called to process an SSH_SMSG_AGENT_OPEN message. */
2899
Damien Miller4af51302000-04-16 11:18:38 +10002900void
Damien Miller62cee002000-09-23 17:15:56 +11002901auth_input_open_request(int type, int plen, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002902{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002903 Channel *c = NULL;
2904 int remote_id, sock;
Ben Lindstrome9c99912001-06-09 00:41:05 +00002905 char *name;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002906
Damien Millerb38eff82000-04-01 11:09:21 +10002907 packet_integrity_check(plen, 4, type);
2908
Damien Miller95def091999-11-25 00:26:21 +11002909 /* Read the remote channel number from the message. */
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002910 remote_id = packet_get_int();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002911
Damien Miller5428f641999-11-25 11:54:57 +11002912 /*
2913 * Get a connection to the local authentication agent (this may again
2914 * get forwarded).
2915 */
Damien Miller95def091999-11-25 00:26:21 +11002916 sock = ssh_get_authentication_socket();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002917
Damien Miller5428f641999-11-25 11:54:57 +11002918 /*
2919 * If we could not connect the agent, send an error message back to
2920 * the server. This should never happen unless the agent dies,
2921 * because authentication forwarding is only enabled if we have an
2922 * agent.
2923 */
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002924 if (sock >= 0) {
Ben Lindstrome9c99912001-06-09 00:41:05 +00002925 name = xstrdup("authentication agent connection");
2926 c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
2927 -1, 0, 0, 0, name, 1);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002928 if (c == NULL) {
2929 error("auth_input_open_request: channel_new failed");
Ben Lindstrome9c99912001-06-09 00:41:05 +00002930 xfree(name);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002931 close(sock);
2932 } else {
2933 c->remote_id = remote_id;
2934 }
Damien Miller95def091999-11-25 00:26:21 +11002935 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002936 if (c == NULL) {
2937 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2938 packet_put_int(remote_id);
2939 } else {
2940 /* Send a confirmation to the remote host. */
2941 debug("Forwarding authentication connection.");
2942 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
2943 packet_put_int(remote_id);
2944 packet_put_int(c->self);
2945 }
Damien Miller95def091999-11-25 00:26:21 +11002946 packet_send();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002947}