blob: cf6742ae35a7dee780e0cfc1daadc371b6af1338 [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.
Damien Millera90fc082002-01-22 23:19:38 +110016 * Copyright (c) 1999, 2000, 2001, 2002 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 Lindstrom8b2eecd2002-07-07 22:11:51 +000042RCSID("$OpenBSD: channels.c,v 1.180 2002/07/04 08:12:15 deraadt 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"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000049#include "log.h"
50#include "misc.h"
Damien Millerd4a8b7e1999-10-27 13:42:43 +100051#include "channels.h"
Damien Millerd4a8b7e1999-10-27 13:42:43 +100052#include "compat.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000053#include "canohost.h"
Damien Miller994cf142000-07-21 10:19:44 +100054#include "key.h"
55#include "authfd.h"
Damien Miller3afe3752001-12-21 12:39:51 +110056#include "pathnames.h"
Damien Miller994cf142000-07-21 10:19:44 +100057
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
Ben Lindstrom226cfa02001-01-22 05:34:40 +0000131/* AF_UNSPEC or AF_INET or AF_INET6 */
Ben Lindstrom908afed2001-10-03 17:34:59 +0000132static int IPv4or6 = AF_UNSPEC;
Ben Lindstrom226cfa02001-01-22 05:34:40 +0000133
Ben Lindstrome9c99912001-06-09 00:41:05 +0000134/* helper */
Ben Lindstrombba81212001-06-25 05:01:22 +0000135static void port_open_helper(Channel *c, char *rtype);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000136
Ben Lindstrome9c99912001-06-09 00:41:05 +0000137/* -- channel core */
Damien Millerb38eff82000-04-01 11:09:21 +1000138
139Channel *
140channel_lookup(int id)
141{
142 Channel *c;
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000143
Ben Lindstrom79548872002-03-05 01:57:44 +0000144 if (id < 0 || id >= channels_alloc) {
Damien Millerb38eff82000-04-01 11:09:21 +1000145 log("channel_lookup: %d: bad id", id);
146 return NULL;
147 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000148 c = channels[id];
149 if (c == NULL) {
Damien Millerb38eff82000-04-01 11:09:21 +1000150 log("channel_lookup: %d: bad id: channel free", id);
151 return NULL;
152 }
153 return c;
154}
155
Damien Miller5428f641999-11-25 11:54:57 +1100156/*
Damien Millere247cc42000-05-07 12:03:14 +1000157 * Register filedescriptors for a channel, used when allocating a channel or
Damien Miller6f83b8e2000-05-02 09:23:45 +1000158 * when the channel consumer/producer is ready, e.g. shell exec'd
Damien Miller5428f641999-11-25 11:54:57 +1100159 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000160
Ben Lindstrombba81212001-06-25 05:01:22 +0000161static void
Damien Miller69b69aa2000-10-28 14:19:58 +1100162channel_register_fds(Channel *c, int rfd, int wfd, int efd,
163 int extusage, int nonblock)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000164{
Damien Miller95def091999-11-25 00:26:21 +1100165 /* Update the maximum file descriptor value. */
Damien Miller5e953212001-01-30 09:14:00 +1100166 channel_max_fd = MAX(channel_max_fd, rfd);
167 channel_max_fd = MAX(channel_max_fd, wfd);
168 channel_max_fd = MAX(channel_max_fd, efd);
169
Damien Miller5428f641999-11-25 11:54:57 +1100170 /* XXX set close-on-exec -markus */
Damien Millere247cc42000-05-07 12:03:14 +1000171
Damien Miller6f83b8e2000-05-02 09:23:45 +1000172 c->rfd = rfd;
173 c->wfd = wfd;
174 c->sock = (rfd == wfd) ? rfd : -1;
175 c->efd = efd;
176 c->extended_usage = extusage;
Damien Miller69b69aa2000-10-28 14:19:58 +1100177
Damien Miller79438cc2001-02-16 12:34:57 +1100178 /* XXX ugly hack: nonblock is only set by the server */
179 if (nonblock && isatty(c->rfd)) {
Ben Lindstromcc74df72001-03-05 06:20:14 +0000180 debug("channel %d: rfd %d isatty", c->self, c->rfd);
Damien Miller79438cc2001-02-16 12:34:57 +1100181 c->isatty = 1;
182 if (!isatty(c->wfd)) {
Ben Lindstromcc74df72001-03-05 06:20:14 +0000183 error("channel %d: wfd %d is not a tty?",
Damien Miller79438cc2001-02-16 12:34:57 +1100184 c->self, c->wfd);
185 }
186 } else {
187 c->isatty = 0;
188 }
189
Damien Miller69b69aa2000-10-28 14:19:58 +1100190 /* enable nonblocking mode */
191 if (nonblock) {
192 if (rfd != -1)
193 set_nonblock(rfd);
194 if (wfd != -1)
195 set_nonblock(wfd);
196 if (efd != -1)
197 set_nonblock(efd);
198 }
Damien Miller6f83b8e2000-05-02 09:23:45 +1000199}
200
201/*
202 * Allocate a new channel object and set its type and socket. This will cause
203 * remote_name to be freed.
204 */
205
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000206Channel *
Damien Miller6f83b8e2000-05-02 09:23:45 +1000207channel_new(char *ctype, int type, int rfd, int wfd, int efd,
Ben Lindstrom4fed2be2002-06-25 23:17:36 +0000208 u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
Damien Miller6f83b8e2000-05-02 09:23:45 +1000209{
210 int i, found;
211 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000212
Damien Miller95def091999-11-25 00:26:21 +1100213 /* Do initial allocation if this is the first call. */
214 if (channels_alloc == 0) {
215 channels_alloc = 10;
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000216 channels = xmalloc(channels_alloc * sizeof(Channel *));
Damien Miller95def091999-11-25 00:26:21 +1100217 for (i = 0; i < channels_alloc; i++)
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000218 channels[i] = NULL;
Ben Lindstrom601e4362001-06-21 03:19:23 +0000219 fatal_add_cleanup((void (*) (void *)) channel_free_all, NULL);
Damien Miller95def091999-11-25 00:26:21 +1100220 }
221 /* Try to find a free slot where to put the new channel. */
222 for (found = -1, i = 0; i < channels_alloc; i++)
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000223 if (channels[i] == NULL) {
Damien Miller95def091999-11-25 00:26:21 +1100224 /* Found a free slot. */
225 found = i;
226 break;
227 }
228 if (found == -1) {
Damien Miller5428f641999-11-25 11:54:57 +1100229 /* There are no free slots. Take last+1 slot and expand the array. */
Damien Miller95def091999-11-25 00:26:21 +1100230 found = channels_alloc;
231 channels_alloc += 10;
Damien Miller9403aa22002-06-26 19:14:43 +1000232 if (channels_alloc > 10000)
233 fatal("channel_new: internal error: channels_alloc %d "
234 "too big.", channels_alloc);
Damien Millerd3444942000-09-30 14:20:03 +1100235 debug2("channel: expanding %d", channels_alloc);
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000236 channels = xrealloc(channels, channels_alloc * sizeof(Channel *));
Damien Miller95def091999-11-25 00:26:21 +1100237 for (i = found; i < channels_alloc; i++)
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000238 channels[i] = NULL;
Damien Miller95def091999-11-25 00:26:21 +1100239 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000240 /* Initialize and return new channel. */
241 c = channels[found] = xmalloc(sizeof(Channel));
Damien Miller4623a752001-10-10 15:03:58 +1000242 memset(c, 0, sizeof(Channel));
Damien Miller95def091999-11-25 00:26:21 +1100243 buffer_init(&c->input);
244 buffer_init(&c->output);
Damien Millerb38eff82000-04-01 11:09:21 +1000245 buffer_init(&c->extended);
Damien Miller5144df92002-01-22 23:28:45 +1100246 c->ostate = CHAN_OUTPUT_OPEN;
247 c->istate = CHAN_INPUT_OPEN;
248 c->flags = 0;
Damien Miller69b69aa2000-10-28 14:19:58 +1100249 channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
Damien Miller95def091999-11-25 00:26:21 +1100250 c->self = found;
251 c->type = type;
Damien Millerb38eff82000-04-01 11:09:21 +1000252 c->ctype = ctype;
Damien Millerbd483e72000-04-30 10:00:53 +1000253 c->local_window = window;
254 c->local_window_max = window;
255 c->local_consumed = 0;
256 c->local_maxpacket = maxpack;
Damien Miller95def091999-11-25 00:26:21 +1100257 c->remote_id = -1;
258 c->remote_name = remote_name;
Damien Millerb38eff82000-04-01 11:09:21 +1000259 c->remote_window = 0;
260 c->remote_maxpacket = 0;
Ben Lindstrom944c4f02001-09-18 05:51:13 +0000261 c->force_drain = 0;
Damien Millere7378562001-12-21 14:58:35 +1100262 c->single_connection = 0;
Ben Lindstrom809744e2001-07-04 05:26:06 +0000263 c->detach_user = NULL;
Damien Miller67f0bc02002-02-05 12:23:08 +1100264 c->confirm = NULL;
Damien Millerad833b32000-08-23 10:46:23 +1000265 c->input_filter = NULL;
Damien Miller95def091999-11-25 00:26:21 +1100266 debug("channel %d: new [%s]", found, remote_name);
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000267 return c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000268}
Damien Miller6f83b8e2000-05-02 09:23:45 +1000269
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000270static int
271channel_find_maxfd(void)
272{
273 int i, max = 0;
274 Channel *c;
275
276 for (i = 0; i < channels_alloc; i++) {
277 c = channels[i];
278 if (c != NULL) {
279 max = MAX(max, c->rfd);
280 max = MAX(max, c->wfd);
281 max = MAX(max, c->efd);
282 }
283 }
284 return max;
285}
286
287int
288channel_close_fd(int *fdp)
289{
290 int ret = 0, fd = *fdp;
291
292 if (fd != -1) {
293 ret = close(fd);
294 *fdp = -1;
295 if (fd == channel_max_fd)
296 channel_max_fd = channel_find_maxfd();
297 }
298 return ret;
299}
300
Damien Miller6f83b8e2000-05-02 09:23:45 +1000301/* Close all channel fd/socket. */
302
Ben Lindstrombba81212001-06-25 05:01:22 +0000303static void
Damien Miller6f83b8e2000-05-02 09:23:45 +1000304channel_close_fds(Channel *c)
305{
Ben Lindstromc0dee1a2001-06-05 20:52:50 +0000306 debug3("channel_close_fds: channel %d: r %d w %d e %d",
307 c->self, c->rfd, c->wfd, c->efd);
308
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000309 channel_close_fd(&c->sock);
310 channel_close_fd(&c->rfd);
311 channel_close_fd(&c->wfd);
312 channel_close_fd(&c->efd);
Damien Miller6f83b8e2000-05-02 09:23:45 +1000313}
314
315/* Free the channel and close its fd/socket. */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000316
Damien Miller4af51302000-04-16 11:18:38 +1000317void
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000318channel_free(Channel *c)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000319{
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000320 char *s;
Ben Lindstromc0dee1a2001-06-05 20:52:50 +0000321 int i, n;
322
323 for (n = 0, i = 0; i < channels_alloc; i++)
324 if (channels[i])
325 n++;
Ben Lindstrom4c247552001-06-05 20:56:47 +0000326 debug("channel_free: channel %d: %s, nchannels %d", c->self,
Ben Lindstromc0dee1a2001-06-05 20:52:50 +0000327 c->remote_name ? c->remote_name : "???", n);
Ben Lindstrom6c3ae2b2000-12-30 03:25:14 +0000328
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000329 s = channel_open_message();
Ben Lindstrom4c247552001-06-05 20:56:47 +0000330 debug3("channel_free: status: %s", s);
Ben Lindstrom6c3ae2b2000-12-30 03:25:14 +0000331 xfree(s);
332
Damien Miller6f83b8e2000-05-02 09:23:45 +1000333 if (c->sock != -1)
Damien Millerb38eff82000-04-01 11:09:21 +1000334 shutdown(c->sock, SHUT_RDWR);
Damien Miller6f83b8e2000-05-02 09:23:45 +1000335 channel_close_fds(c);
Damien Millerb38eff82000-04-01 11:09:21 +1000336 buffer_free(&c->input);
337 buffer_free(&c->output);
338 buffer_free(&c->extended);
Damien Millerb38eff82000-04-01 11:09:21 +1000339 if (c->remote_name) {
340 xfree(c->remote_name);
341 c->remote_name = NULL;
Damien Miller95def091999-11-25 00:26:21 +1100342 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000343 channels[c->self] = NULL;
344 xfree(c);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000345}
346
Ben Lindstrome9c99912001-06-09 00:41:05 +0000347void
Ben Lindstrom601e4362001-06-21 03:19:23 +0000348channel_free_all(void)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000349{
350 int i;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000351
Ben Lindstrom601e4362001-06-21 03:19:23 +0000352 for (i = 0; i < channels_alloc; i++)
353 if (channels[i] != NULL)
354 channel_free(channels[i]);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000355}
356
357/*
358 * Closes the sockets/fds of all channels. This is used to close extra file
359 * descriptors after a fork.
360 */
361
362void
Ben Lindstrom3c36bb22001-12-06 17:55:26 +0000363channel_close_all(void)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000364{
365 int i;
366
367 for (i = 0; i < channels_alloc; i++)
368 if (channels[i] != NULL)
369 channel_close_fds(channels[i]);
370}
371
372/*
Ben Lindstrom809744e2001-07-04 05:26:06 +0000373 * Stop listening to channels.
374 */
375
376void
377channel_stop_listening(void)
378{
379 int i;
380 Channel *c;
381
382 for (i = 0; i < channels_alloc; i++) {
383 c = channels[i];
384 if (c != NULL) {
385 switch (c->type) {
386 case SSH_CHANNEL_AUTH_SOCKET:
387 case SSH_CHANNEL_PORT_LISTENER:
388 case SSH_CHANNEL_RPORT_LISTENER:
389 case SSH_CHANNEL_X11_LISTENER:
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000390 channel_close_fd(&c->sock);
Ben Lindstrom809744e2001-07-04 05:26:06 +0000391 channel_free(c);
392 break;
393 }
394 }
395 }
396}
397
398/*
Ben Lindstrome9c99912001-06-09 00:41:05 +0000399 * Returns true if no channel has too much buffered data, and false if one or
400 * more channel is overfull.
401 */
402
403int
Ben Lindstrom3c36bb22001-12-06 17:55:26 +0000404channel_not_very_much_buffered_data(void)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000405{
406 u_int i;
407 Channel *c;
408
409 for (i = 0; i < channels_alloc; i++) {
410 c = channels[i];
411 if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
Damien Milleraf5f2e62001-10-10 15:01:16 +1000412#if 0
413 if (!compat20 &&
414 buffer_len(&c->input) > packet_get_maxsize()) {
Ben Lindstrome9c99912001-06-09 00:41:05 +0000415 debug("channel %d: big input buffer %d",
416 c->self, buffer_len(&c->input));
417 return 0;
418 }
Damien Milleraf5f2e62001-10-10 15:01:16 +1000419#endif
Ben Lindstrome9c99912001-06-09 00:41:05 +0000420 if (buffer_len(&c->output) > packet_get_maxsize()) {
Damien Milleraf5f2e62001-10-10 15:01:16 +1000421 debug("channel %d: big output buffer %d > %d",
422 c->self, buffer_len(&c->output),
423 packet_get_maxsize());
Ben Lindstrome9c99912001-06-09 00:41:05 +0000424 return 0;
425 }
426 }
427 }
428 return 1;
429}
430
431/* Returns true if any channel is still open. */
432
433int
Ben Lindstrom3c36bb22001-12-06 17:55:26 +0000434channel_still_open(void)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000435{
436 int i;
437 Channel *c;
438
439 for (i = 0; i < channels_alloc; i++) {
440 c = channels[i];
441 if (c == NULL)
442 continue;
443 switch (c->type) {
444 case SSH_CHANNEL_X11_LISTENER:
445 case SSH_CHANNEL_PORT_LISTENER:
446 case SSH_CHANNEL_RPORT_LISTENER:
447 case SSH_CHANNEL_CLOSED:
448 case SSH_CHANNEL_AUTH_SOCKET:
449 case SSH_CHANNEL_DYNAMIC:
450 case SSH_CHANNEL_CONNECTING:
451 case SSH_CHANNEL_ZOMBIE:
452 continue;
453 case SSH_CHANNEL_LARVAL:
454 if (!compat20)
455 fatal("cannot happen: SSH_CHANNEL_LARVAL");
456 continue;
457 case SSH_CHANNEL_OPENING:
458 case SSH_CHANNEL_OPEN:
459 case SSH_CHANNEL_X11_OPEN:
460 return 1;
461 case SSH_CHANNEL_INPUT_DRAINING:
462 case SSH_CHANNEL_OUTPUT_DRAINING:
463 if (!compat13)
464 fatal("cannot happen: OUT_DRAIN");
465 return 1;
466 default:
467 fatal("channel_still_open: bad channel type %d", c->type);
468 /* NOTREACHED */
469 }
470 }
471 return 0;
472}
473
474/* Returns the id of an open channel suitable for keepaliving */
475
476int
Ben Lindstrom3c36bb22001-12-06 17:55:26 +0000477channel_find_open(void)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000478{
479 int i;
480 Channel *c;
481
482 for (i = 0; i < channels_alloc; i++) {
483 c = channels[i];
484 if (c == NULL)
485 continue;
486 switch (c->type) {
487 case SSH_CHANNEL_CLOSED:
488 case SSH_CHANNEL_DYNAMIC:
489 case SSH_CHANNEL_X11_LISTENER:
490 case SSH_CHANNEL_PORT_LISTENER:
491 case SSH_CHANNEL_RPORT_LISTENER:
492 case SSH_CHANNEL_OPENING:
493 case SSH_CHANNEL_CONNECTING:
494 case SSH_CHANNEL_ZOMBIE:
495 continue;
496 case SSH_CHANNEL_LARVAL:
497 case SSH_CHANNEL_AUTH_SOCKET:
498 case SSH_CHANNEL_OPEN:
499 case SSH_CHANNEL_X11_OPEN:
500 return i;
501 case SSH_CHANNEL_INPUT_DRAINING:
502 case SSH_CHANNEL_OUTPUT_DRAINING:
503 if (!compat13)
504 fatal("cannot happen: OUT_DRAIN");
505 return i;
506 default:
507 fatal("channel_find_open: bad channel type %d", c->type);
508 /* NOTREACHED */
509 }
510 }
511 return -1;
512}
513
514
515/*
516 * Returns a message describing the currently open forwarded connections,
517 * suitable for sending to the client. The message contains crlf pairs for
518 * newlines.
519 */
520
521char *
Ben Lindstrom3c36bb22001-12-06 17:55:26 +0000522channel_open_message(void)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000523{
524 Buffer buffer;
525 Channel *c;
526 char buf[1024], *cp;
527 int i;
528
529 buffer_init(&buffer);
530 snprintf(buf, sizeof buf, "The following connections are open:\r\n");
531 buffer_append(&buffer, buf, strlen(buf));
532 for (i = 0; i < channels_alloc; i++) {
533 c = channels[i];
534 if (c == NULL)
535 continue;
536 switch (c->type) {
537 case SSH_CHANNEL_X11_LISTENER:
538 case SSH_CHANNEL_PORT_LISTENER:
539 case SSH_CHANNEL_RPORT_LISTENER:
540 case SSH_CHANNEL_CLOSED:
541 case SSH_CHANNEL_AUTH_SOCKET:
542 case SSH_CHANNEL_ZOMBIE:
543 continue;
544 case SSH_CHANNEL_LARVAL:
545 case SSH_CHANNEL_OPENING:
546 case SSH_CHANNEL_CONNECTING:
547 case SSH_CHANNEL_DYNAMIC:
548 case SSH_CHANNEL_OPEN:
549 case SSH_CHANNEL_X11_OPEN:
550 case SSH_CHANNEL_INPUT_DRAINING:
551 case SSH_CHANNEL_OUTPUT_DRAINING:
552 snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n",
553 c->self, c->remote_name,
554 c->type, c->remote_id,
555 c->istate, buffer_len(&c->input),
556 c->ostate, buffer_len(&c->output),
557 c->rfd, c->wfd);
558 buffer_append(&buffer, buf, strlen(buf));
559 continue;
560 default:
561 fatal("channel_open_message: bad channel type %d", c->type);
562 /* NOTREACHED */
563 }
564 }
565 buffer_append(&buffer, "\0", 1);
566 cp = xstrdup(buffer_ptr(&buffer));
567 buffer_free(&buffer);
568 return cp;
569}
570
571void
572channel_send_open(int id)
573{
574 Channel *c = channel_lookup(id);
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000575
Ben Lindstrome9c99912001-06-09 00:41:05 +0000576 if (c == NULL) {
577 log("channel_send_open: %d: bad id", id);
578 return;
579 }
580 debug("send channel open %d", id);
581 packet_start(SSH2_MSG_CHANNEL_OPEN);
582 packet_put_cstring(c->ctype);
583 packet_put_int(c->self);
584 packet_put_int(c->local_window);
585 packet_put_int(c->local_maxpacket);
586 packet_send();
587}
588
589void
Damien Millera500cd62002-02-08 22:04:26 +1100590channel_request_start(int local_id, char *service, int wantconfirm)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000591{
Damien Millera500cd62002-02-08 22:04:26 +1100592 Channel *c = channel_lookup(local_id);
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000593
Ben Lindstrome9c99912001-06-09 00:41:05 +0000594 if (c == NULL) {
Damien Millera500cd62002-02-08 22:04:26 +1100595 log("channel_request_start: %d: unknown channel id", local_id);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000596 return;
597 }
Damien Millera500cd62002-02-08 22:04:26 +1100598 debug("channel request %d: %s", local_id, service) ;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000599 packet_start(SSH2_MSG_CHANNEL_REQUEST);
600 packet_put_int(c->remote_id);
601 packet_put_cstring(service);
602 packet_put_char(wantconfirm);
603}
604void
Damien Miller67f0bc02002-02-05 12:23:08 +1100605channel_register_confirm(int id, channel_callback_fn *fn)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000606{
607 Channel *c = channel_lookup(id);
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000608
Ben Lindstrome9c99912001-06-09 00:41:05 +0000609 if (c == NULL) {
Damien Miller67f0bc02002-02-05 12:23:08 +1100610 log("channel_register_comfirm: %d: bad id", id);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000611 return;
612 }
Damien Miller67f0bc02002-02-05 12:23:08 +1100613 c->confirm = fn;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000614}
615void
616channel_register_cleanup(int id, channel_callback_fn *fn)
617{
618 Channel *c = channel_lookup(id);
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000619
Ben Lindstrome9c99912001-06-09 00:41:05 +0000620 if (c == NULL) {
621 log("channel_register_cleanup: %d: bad id", id);
622 return;
623 }
Ben Lindstrom809744e2001-07-04 05:26:06 +0000624 c->detach_user = fn;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000625}
626void
627channel_cancel_cleanup(int id)
628{
629 Channel *c = channel_lookup(id);
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000630
Ben Lindstrome9c99912001-06-09 00:41:05 +0000631 if (c == NULL) {
632 log("channel_cancel_cleanup: %d: bad id", id);
633 return;
634 }
Ben Lindstrom809744e2001-07-04 05:26:06 +0000635 c->detach_user = NULL;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000636}
637void
638channel_register_filter(int id, channel_filter_fn *fn)
639{
640 Channel *c = channel_lookup(id);
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000641
Ben Lindstrome9c99912001-06-09 00:41:05 +0000642 if (c == NULL) {
643 log("channel_register_filter: %d: bad id", id);
644 return;
645 }
646 c->input_filter = fn;
647}
648
649void
650channel_set_fds(int id, int rfd, int wfd, int efd,
Damien Miller2aa0c192002-02-19 15:20:08 +1100651 int extusage, int nonblock, u_int window_max)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000652{
653 Channel *c = channel_lookup(id);
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000654
Ben Lindstrome9c99912001-06-09 00:41:05 +0000655 if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
656 fatal("channel_activate for non-larval channel %d.", id);
657 channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
658 c->type = SSH_CHANNEL_OPEN;
Damien Miller2aa0c192002-02-19 15:20:08 +1100659 c->local_window = c->local_window_max = window_max;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000660 packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
661 packet_put_int(c->remote_id);
662 packet_put_int(c->local_window);
663 packet_send();
664}
665
Damien Miller5428f641999-11-25 11:54:57 +1100666/*
Damien Millerb38eff82000-04-01 11:09:21 +1000667 * 'channel_pre*' are called just before select() to add any bits relevant to
668 * channels in the select bitmasks.
Damien Miller5428f641999-11-25 11:54:57 +1100669 */
Damien Millerb38eff82000-04-01 11:09:21 +1000670/*
671 * 'channel_post*': perform any appropriate operations for channels which
672 * have events pending.
673 */
674typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset);
675chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
676chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
677
Ben Lindstrombba81212001-06-25 05:01:22 +0000678static void
Damien Millerb38eff82000-04-01 11:09:21 +1000679channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset)
680{
681 FD_SET(c->sock, readset);
682}
683
Ben Lindstrombba81212001-06-25 05:01:22 +0000684static void
Ben Lindstrom7ad97102000-12-06 01:42:49 +0000685channel_pre_connecting(Channel *c, fd_set * readset, fd_set * writeset)
686{
687 debug3("channel %d: waiting for connection", c->self);
688 FD_SET(c->sock, writeset);
689}
690
Ben Lindstrombba81212001-06-25 05:01:22 +0000691static void
Damien Millerb38eff82000-04-01 11:09:21 +1000692channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset)
693{
694 if (buffer_len(&c->input) < packet_get_maxsize())
695 FD_SET(c->sock, readset);
696 if (buffer_len(&c->output) > 0)
697 FD_SET(c->sock, writeset);
698}
699
Ben Lindstrombba81212001-06-25 05:01:22 +0000700static void
Damien Millerde6987c2002-01-22 23:20:40 +1100701channel_pre_open(Channel *c, fd_set * readset, fd_set * writeset)
Damien Millerb38eff82000-04-01 11:09:21 +1000702{
Damien Millerde6987c2002-01-22 23:20:40 +1100703 u_int limit = compat20 ? c->remote_window : packet_get_maxsize();
Damien Millerb38eff82000-04-01 11:09:21 +1000704
Damien Miller33b13562000-04-04 14:38:59 +1000705 if (c->istate == CHAN_INPUT_OPEN &&
Damien Millerde6987c2002-01-22 23:20:40 +1100706 limit > 0 &&
707 buffer_len(&c->input) < limit)
Damien Miller33b13562000-04-04 14:38:59 +1000708 FD_SET(c->rfd, readset);
709 if (c->ostate == CHAN_OUTPUT_OPEN ||
710 c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
711 if (buffer_len(&c->output) > 0) {
712 FD_SET(c->wfd, writeset);
713 } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
Ben Lindstromcf159442002-03-26 03:26:24 +0000714 if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
Ben Lindstrom5a6abda2002-06-09 19:41:48 +0000715 debug2("channel %d: obuf_empty delayed efd %d/(%d)",
716 c->self, c->efd, buffer_len(&c->extended));
Ben Lindstromcf159442002-03-26 03:26:24 +0000717 else
718 chan_obuf_empty(c);
Damien Miller33b13562000-04-04 14:38:59 +1000719 }
720 }
721 /** XXX check close conditions, too */
Damien Millerde6987c2002-01-22 23:20:40 +1100722 if (compat20 && c->efd != -1) {
Damien Miller33b13562000-04-04 14:38:59 +1000723 if (c->extended_usage == CHAN_EXTENDED_WRITE &&
724 buffer_len(&c->extended) > 0)
725 FD_SET(c->efd, writeset);
Ben Lindstromcf159442002-03-26 03:26:24 +0000726 else if (!(c->flags & CHAN_EOF_SENT) &&
727 c->extended_usage == CHAN_EXTENDED_READ &&
Damien Miller33b13562000-04-04 14:38:59 +1000728 buffer_len(&c->extended) < c->remote_window)
729 FD_SET(c->efd, readset);
730 }
731}
732
Ben Lindstrombba81212001-06-25 05:01:22 +0000733static void
Damien Millerb38eff82000-04-01 11:09:21 +1000734channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset)
735{
736 if (buffer_len(&c->input) == 0) {
737 packet_start(SSH_MSG_CHANNEL_CLOSE);
738 packet_put_int(c->remote_id);
739 packet_send();
740 c->type = SSH_CHANNEL_CLOSED;
Ben Lindstromc486d882001-04-11 16:08:34 +0000741 debug("channel %d: closing after input drain.", c->self);
Damien Millerb38eff82000-04-01 11:09:21 +1000742 }
743}
744
Ben Lindstrombba81212001-06-25 05:01:22 +0000745static void
Damien Millerb38eff82000-04-01 11:09:21 +1000746channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset)
747{
748 if (buffer_len(&c->output) == 0)
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000749 chan_mark_dead(c);
Damien Miller4af51302000-04-16 11:18:38 +1000750 else
Damien Millerb38eff82000-04-01 11:09:21 +1000751 FD_SET(c->sock, writeset);
752}
753
754/*
755 * This is a special state for X11 authentication spoofing. An opened X11
756 * connection (when authentication spoofing is being done) remains in this
757 * state until the first packet has been completely read. The authentication
758 * data in that packet is then substituted by the real data if it matches the
759 * fake data, and the channel is put into normal mode.
Damien Millerbd483e72000-04-30 10:00:53 +1000760 * XXX All this happens at the client side.
Ben Lindstrome9c99912001-06-09 00:41:05 +0000761 * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
Damien Millerb38eff82000-04-01 11:09:21 +1000762 */
Ben Lindstrombba81212001-06-25 05:01:22 +0000763static int
Ben Lindstrome9c99912001-06-09 00:41:05 +0000764x11_open_helper(Buffer *b)
Damien Millerb38eff82000-04-01 11:09:21 +1000765{
Ben Lindstrom46c16222000-12-22 01:43:59 +0000766 u_char *ucp;
767 u_int proto_len, data_len;
Damien Millerb38eff82000-04-01 11:09:21 +1000768
769 /* Check if the fixed size part of the packet is in buffer. */
Ben Lindstrome9c99912001-06-09 00:41:05 +0000770 if (buffer_len(b) < 12)
Damien Millerb38eff82000-04-01 11:09:21 +1000771 return 0;
772
773 /* Parse the lengths of variable-length fields. */
Damien Miller708d21c2002-01-22 23:18:15 +1100774 ucp = buffer_ptr(b);
Damien Millerb38eff82000-04-01 11:09:21 +1000775 if (ucp[0] == 0x42) { /* Byte order MSB first. */
776 proto_len = 256 * ucp[6] + ucp[7];
777 data_len = 256 * ucp[8] + ucp[9];
778 } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
779 proto_len = ucp[6] + 256 * ucp[7];
780 data_len = ucp[8] + 256 * ucp[9];
781 } else {
782 debug("Initial X11 packet contains bad byte order byte: 0x%x",
Damien Miller9f0f5c62001-12-21 14:45:46 +1100783 ucp[0]);
Damien Millerb38eff82000-04-01 11:09:21 +1000784 return -1;
785 }
786
787 /* Check if the whole packet is in buffer. */
Ben Lindstrome9c99912001-06-09 00:41:05 +0000788 if (buffer_len(b) <
Damien Millerb38eff82000-04-01 11:09:21 +1000789 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
790 return 0;
791
792 /* Check if authentication protocol matches. */
793 if (proto_len != strlen(x11_saved_proto) ||
794 memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
795 debug("X11 connection uses different authentication protocol.");
796 return -1;
797 }
798 /* Check if authentication data matches our fake data. */
799 if (data_len != x11_fake_data_len ||
800 memcmp(ucp + 12 + ((proto_len + 3) & ~3),
801 x11_fake_data, x11_fake_data_len) != 0) {
802 debug("X11 auth data does not match fake data.");
803 return -1;
804 }
805 /* Check fake data length */
806 if (x11_fake_data_len != x11_saved_data_len) {
807 error("X11 fake_data_len %d != saved_data_len %d",
808 x11_fake_data_len, x11_saved_data_len);
809 return -1;
810 }
811 /*
812 * Received authentication protocol and data match
813 * our fake data. Substitute the fake data with real
814 * data.
815 */
816 memcpy(ucp + 12 + ((proto_len + 3) & ~3),
817 x11_saved_data, x11_saved_data_len);
818 return 1;
819}
820
Ben Lindstrombba81212001-06-25 05:01:22 +0000821static void
Damien Millerb38eff82000-04-01 11:09:21 +1000822channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset)
823{
Ben Lindstrome9c99912001-06-09 00:41:05 +0000824 int ret = x11_open_helper(&c->output);
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000825
Damien Millerb38eff82000-04-01 11:09:21 +1000826 if (ret == 1) {
827 /* Start normal processing for the channel. */
828 c->type = SSH_CHANNEL_OPEN;
Damien Miller78928792000-04-12 20:17:38 +1000829 channel_pre_open_13(c, readset, writeset);
Damien Millerb38eff82000-04-01 11:09:21 +1000830 } else if (ret == -1) {
831 /*
832 * We have received an X11 connection that has bad
833 * authentication information.
834 */
Ben Lindstrom6df8ef42001-03-05 07:47:23 +0000835 log("X11 connection rejected because of wrong authentication.");
Damien Millerb38eff82000-04-01 11:09:21 +1000836 buffer_clear(&c->input);
837 buffer_clear(&c->output);
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000838 channel_close_fd(&c->sock);
Damien Millerb38eff82000-04-01 11:09:21 +1000839 c->sock = -1;
840 c->type = SSH_CHANNEL_CLOSED;
841 packet_start(SSH_MSG_CHANNEL_CLOSE);
842 packet_put_int(c->remote_id);
843 packet_send();
844 }
845}
846
Ben Lindstrombba81212001-06-25 05:01:22 +0000847static void
Damien Millerbd483e72000-04-30 10:00:53 +1000848channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset)
Damien Millerb38eff82000-04-01 11:09:21 +1000849{
Ben Lindstrome9c99912001-06-09 00:41:05 +0000850 int ret = x11_open_helper(&c->output);
Ben Lindstrom944c4f02001-09-18 05:51:13 +0000851
852 /* c->force_drain = 1; */
853
Damien Millerb38eff82000-04-01 11:09:21 +1000854 if (ret == 1) {
855 c->type = SSH_CHANNEL_OPEN;
Damien Millerde6987c2002-01-22 23:20:40 +1100856 channel_pre_open(c, readset, writeset);
Damien Millerb38eff82000-04-01 11:09:21 +1000857 } else if (ret == -1) {
Damien Millera90fc082002-01-22 23:19:38 +1100858 log("X11 connection rejected because of wrong authentication.");
Damien Millerb38eff82000-04-01 11:09:21 +1000859 debug("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
Damien Millera90fc082002-01-22 23:19:38 +1100860 chan_read_failed(c);
861 buffer_clear(&c->input);
862 chan_ibuf_empty(c);
863 buffer_clear(&c->output);
864 /* for proto v1, the peer will send an IEOF */
865 if (compat20)
866 chan_write_failed(c);
867 else
868 c->type = SSH_CHANNEL_OPEN;
Damien Millerb38eff82000-04-01 11:09:21 +1000869 debug("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
870 }
871}
872
Ben Lindstromb3921512001-04-11 15:57:50 +0000873/* try to decode a socks4 header */
Ben Lindstrombba81212001-06-25 05:01:22 +0000874static int
Ben Lindstromb3921512001-04-11 15:57:50 +0000875channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset)
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000876{
877 u_char *p, *host;
Ben Lindstrom2b261b92001-04-17 18:14:34 +0000878 int len, have, i, found;
Damien Miller9f0f5c62001-12-21 14:45:46 +1100879 char username[256];
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000880 struct {
881 u_int8_t version;
882 u_int8_t command;
883 u_int16_t dest_port;
Ben Lindstromb3921512001-04-11 15:57:50 +0000884 struct in_addr dest_addr;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000885 } s4_req, s4_rsp;
886
Ben Lindstromb3921512001-04-11 15:57:50 +0000887 debug2("channel %d: decode socks4", c->self);
Ben Lindstrom2b261b92001-04-17 18:14:34 +0000888
889 have = buffer_len(&c->input);
890 len = sizeof(s4_req);
891 if (have < len)
892 return 0;
893 p = buffer_ptr(&c->input);
894 for (found = 0, i = len; i < have; i++) {
895 if (p[i] == '\0') {
896 found = 1;
897 break;
898 }
899 if (i > 1024) {
900 /* the peer is probably sending garbage */
901 debug("channel %d: decode socks4: too long",
902 c->self);
903 return -1;
904 }
905 }
906 if (!found)
907 return 0;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000908 buffer_get(&c->input, (char *)&s4_req.version, 1);
909 buffer_get(&c->input, (char *)&s4_req.command, 1);
910 buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
Ben Lindstromb3921512001-04-11 15:57:50 +0000911 buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
Ben Lindstrom2b261b92001-04-17 18:14:34 +0000912 have = buffer_len(&c->input);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000913 p = buffer_ptr(&c->input);
914 len = strlen(p);
Ben Lindstrom6fa9d102001-04-11 23:08:17 +0000915 debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000916 if (len > have)
Ben Lindstromb3921512001-04-11 15:57:50 +0000917 fatal("channel %d: decode socks4: len %d > have %d",
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000918 c->self, len, have);
919 strlcpy(username, p, sizeof(username));
920 buffer_consume(&c->input, len);
921 buffer_consume(&c->input, 1); /* trailing '\0' */
922
Ben Lindstromb3921512001-04-11 15:57:50 +0000923 host = inet_ntoa(s4_req.dest_addr);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000924 strlcpy(c->path, host, sizeof(c->path));
925 c->host_port = ntohs(s4_req.dest_port);
Damien Miller9f0f5c62001-12-21 14:45:46 +1100926
Ben Lindstrom6fa9d102001-04-11 23:08:17 +0000927 debug("channel %d: dynamic request: socks4 host %s port %u command %u",
928 c->self, host, c->host_port, s4_req.command);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000929
Ben Lindstromb3921512001-04-11 15:57:50 +0000930 if (s4_req.command != 1) {
931 debug("channel %d: cannot handle: socks4 cn %d",
932 c->self, s4_req.command);
933 return -1;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000934 }
Ben Lindstromb3921512001-04-11 15:57:50 +0000935 s4_rsp.version = 0; /* vn: 0 for reply */
936 s4_rsp.command = 90; /* cd: req granted */
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000937 s4_rsp.dest_port = 0; /* ignored */
Ben Lindstromb3921512001-04-11 15:57:50 +0000938 s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000939 buffer_append(&c->output, (char *)&s4_rsp, sizeof(s4_rsp));
Ben Lindstromb3921512001-04-11 15:57:50 +0000940 return 1;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000941}
942
Ben Lindstromb3921512001-04-11 15:57:50 +0000943/* dynamic port forwarding */
Ben Lindstrombba81212001-06-25 05:01:22 +0000944static void
Ben Lindstromb3921512001-04-11 15:57:50 +0000945channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset)
946{
947 u_char *p;
948 int have, ret;
949
950 have = buffer_len(&c->input);
Damien Miller4623a752001-10-10 15:03:58 +1000951 c->delayed = 0;
Ben Lindstromb3921512001-04-11 15:57:50 +0000952 debug2("channel %d: pre_dynamic: have %d", c->self, have);
Ben Lindstromc486d882001-04-11 16:08:34 +0000953 /* buffer_dump(&c->input); */
Ben Lindstromb3921512001-04-11 15:57:50 +0000954 /* check if the fixed size part of the packet is in buffer. */
955 if (have < 4) {
956 /* need more */
957 FD_SET(c->sock, readset);
958 return;
959 }
960 /* try to guess the protocol */
961 p = buffer_ptr(&c->input);
962 switch (p[0]) {
Ben Lindstrom6fa9d102001-04-11 23:08:17 +0000963 case 0x04:
964 ret = channel_decode_socks4(c, readset, writeset);
965 break;
Ben Lindstromb3921512001-04-11 15:57:50 +0000966 default:
967 ret = -1;
968 break;
969 }
970 if (ret < 0) {
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000971 chan_mark_dead(c);
Ben Lindstromb3921512001-04-11 15:57:50 +0000972 } else if (ret == 0) {
973 debug2("channel %d: pre_dynamic: need more", c->self);
974 /* need more */
975 FD_SET(c->sock, readset);
976 } else {
977 /* switch to the next state */
978 c->type = SSH_CHANNEL_OPENING;
979 port_open_helper(c, "direct-tcpip");
980 }
981}
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000982
Damien Millerb38eff82000-04-01 11:09:21 +1000983/* This is our fake X11 server socket. */
Ben Lindstrombba81212001-06-25 05:01:22 +0000984static void
Damien Millerb38eff82000-04-01 11:09:21 +1000985channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset)
986{
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000987 Channel *nc;
Damien Millerb38eff82000-04-01 11:09:21 +1000988 struct sockaddr addr;
Damien Miller398e1cf2002-02-05 11:52:13 +1100989 int newsock;
Damien Millerb38eff82000-04-01 11:09:21 +1000990 socklen_t addrlen;
Damien Millerd83ff352001-01-30 09:19:34 +1100991 char buf[16384], *remote_ipaddr;
Damien Millerbd483e72000-04-30 10:00:53 +1000992 int remote_port;
Damien Millerb38eff82000-04-01 11:09:21 +1000993
994 if (FD_ISSET(c->sock, readset)) {
995 debug("X11 connection requested.");
996 addrlen = sizeof(addr);
997 newsock = accept(c->sock, &addr, &addrlen);
Damien Millere7378562001-12-21 14:58:35 +1100998 if (c->single_connection) {
999 debug("single_connection: closing X11 listener.");
1000 channel_close_fd(&c->sock);
1001 chan_mark_dead(c);
1002 }
Damien Millerb38eff82000-04-01 11:09:21 +10001003 if (newsock < 0) {
1004 error("accept: %.100s", strerror(errno));
1005 return;
1006 }
Damien Miller398e1cf2002-02-05 11:52:13 +11001007 set_nodelay(newsock);
Damien Millerd83ff352001-01-30 09:19:34 +11001008 remote_ipaddr = get_peer_ipaddr(newsock);
Damien Millerbd483e72000-04-30 10:00:53 +10001009 remote_port = get_peer_port(newsock);
Damien Millerb38eff82000-04-01 11:09:21 +10001010 snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
Damien Millerd83ff352001-01-30 09:19:34 +11001011 remote_ipaddr, remote_port);
Damien Millerbd483e72000-04-30 10:00:53 +10001012
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001013 nc = channel_new("accepted x11 socket",
Damien Millerbd483e72000-04-30 10:00:53 +10001014 SSH_CHANNEL_OPENING, newsock, newsock, -1,
1015 c->local_window_max, c->local_maxpacket,
Damien Miller69b69aa2000-10-28 14:19:58 +11001016 0, xstrdup(buf), 1);
Damien Millerbd483e72000-04-30 10:00:53 +10001017 if (compat20) {
1018 packet_start(SSH2_MSG_CHANNEL_OPEN);
1019 packet_put_cstring("x11");
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001020 packet_put_int(nc->self);
Damien Millere7378562001-12-21 14:58:35 +11001021 packet_put_int(nc->local_window_max);
1022 packet_put_int(nc->local_maxpacket);
Damien Millerd83ff352001-01-30 09:19:34 +11001023 /* originator ipaddr and port */
1024 packet_put_cstring(remote_ipaddr);
Damien Miller30c3d422000-05-09 11:02:59 +10001025 if (datafellows & SSH_BUG_X11FWD) {
1026 debug("ssh2 x11 bug compat mode");
1027 } else {
1028 packet_put_int(remote_port);
1029 }
Damien Millerbd483e72000-04-30 10:00:53 +10001030 packet_send();
1031 } else {
1032 packet_start(SSH_SMSG_X11_OPEN);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001033 packet_put_int(nc->self);
Ben Lindstrome9c99912001-06-09 00:41:05 +00001034 if (packet_get_protocol_flags() &
1035 SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
Ben Lindstrom664408d2001-06-09 01:42:01 +00001036 packet_put_cstring(buf);
Damien Millerbd483e72000-04-30 10:00:53 +10001037 packet_send();
1038 }
Damien Millerd83ff352001-01-30 09:19:34 +11001039 xfree(remote_ipaddr);
Damien Millerb38eff82000-04-01 11:09:21 +10001040 }
1041}
1042
Ben Lindstrombba81212001-06-25 05:01:22 +00001043static void
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001044port_open_helper(Channel *c, char *rtype)
1045{
1046 int direct;
1047 char buf[1024];
1048 char *remote_ipaddr = get_peer_ipaddr(c->sock);
1049 u_short remote_port = get_peer_port(c->sock);
1050
1051 direct = (strcmp(rtype, "direct-tcpip") == 0);
1052
1053 snprintf(buf, sizeof buf,
1054 "%s: listening port %d for %.100s port %d, "
1055 "connect from %.200s port %d",
1056 rtype, c->listening_port, c->path, c->host_port,
1057 remote_ipaddr, remote_port);
1058
1059 xfree(c->remote_name);
1060 c->remote_name = xstrdup(buf);
1061
1062 if (compat20) {
1063 packet_start(SSH2_MSG_CHANNEL_OPEN);
1064 packet_put_cstring(rtype);
1065 packet_put_int(c->self);
1066 packet_put_int(c->local_window_max);
1067 packet_put_int(c->local_maxpacket);
1068 if (direct) {
1069 /* target host, port */
1070 packet_put_cstring(c->path);
1071 packet_put_int(c->host_port);
1072 } else {
1073 /* listen address, port */
1074 packet_put_cstring(c->path);
1075 packet_put_int(c->listening_port);
1076 }
1077 /* originator host and port */
1078 packet_put_cstring(remote_ipaddr);
1079 packet_put_int(remote_port);
1080 packet_send();
1081 } else {
1082 packet_start(SSH_MSG_PORT_OPEN);
1083 packet_put_int(c->self);
1084 packet_put_cstring(c->path);
1085 packet_put_int(c->host_port);
Ben Lindstrome9c99912001-06-09 00:41:05 +00001086 if (packet_get_protocol_flags() &
1087 SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001088 packet_put_cstring(c->remote_name);
1089 packet_send();
1090 }
1091 xfree(remote_ipaddr);
1092}
1093
Damien Millerb38eff82000-04-01 11:09:21 +10001094/*
1095 * This socket is listening for connections to a forwarded TCP/IP port.
1096 */
Ben Lindstrombba81212001-06-25 05:01:22 +00001097static void
Damien Millerb38eff82000-04-01 11:09:21 +10001098channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset)
1099{
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001100 Channel *nc;
Damien Millerb38eff82000-04-01 11:09:21 +10001101 struct sockaddr addr;
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001102 int newsock, nextstate;
Damien Millerb38eff82000-04-01 11:09:21 +10001103 socklen_t addrlen;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001104 char *rtype;
Damien Miller0bc1bd82000-11-13 22:57:25 +11001105
Damien Millerb38eff82000-04-01 11:09:21 +10001106 if (FD_ISSET(c->sock, readset)) {
1107 debug("Connection to port %d forwarding "
1108 "to %.100s port %d requested.",
1109 c->listening_port, c->path, c->host_port);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001110
Damien Miller4623a752001-10-10 15:03:58 +10001111 if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1112 nextstate = SSH_CHANNEL_OPENING;
1113 rtype = "forwarded-tcpip";
1114 } else {
1115 if (c->host_port == 0) {
1116 nextstate = SSH_CHANNEL_DYNAMIC;
Damien Millerd3c04b92001-10-10 15:04:20 +10001117 rtype = "dynamic-tcpip";
Damien Miller4623a752001-10-10 15:03:58 +10001118 } else {
1119 nextstate = SSH_CHANNEL_OPENING;
1120 rtype = "direct-tcpip";
1121 }
1122 }
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001123
Damien Millerb38eff82000-04-01 11:09:21 +10001124 addrlen = sizeof(addr);
1125 newsock = accept(c->sock, &addr, &addrlen);
1126 if (newsock < 0) {
1127 error("accept: %.100s", strerror(errno));
1128 return;
1129 }
Ben Lindstrom1ebd7a52002-02-26 18:12:51 +00001130 set_nodelay(newsock);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001131 nc = channel_new(rtype,
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001132 nextstate, newsock, newsock, -1,
Damien Millerb38eff82000-04-01 11:09:21 +10001133 c->local_window_max, c->local_maxpacket,
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001134 0, xstrdup(rtype), 1);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001135 nc->listening_port = c->listening_port;
1136 nc->host_port = c->host_port;
1137 strlcpy(nc->path, c->path, sizeof(nc->path));
1138
Damien Miller4623a752001-10-10 15:03:58 +10001139 if (nextstate == SSH_CHANNEL_DYNAMIC) {
1140 /*
1141 * do not call the channel_post handler until
1142 * this flag has been reset by a pre-handler.
1143 * otherwise the FD_ISSET calls might overflow
1144 */
1145 nc->delayed = 1;
1146 } else {
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001147 port_open_helper(nc, rtype);
Damien Miller4623a752001-10-10 15:03:58 +10001148 }
Damien Millerb38eff82000-04-01 11:09:21 +10001149 }
1150}
1151
1152/*
1153 * This is the authentication agent socket listening for connections from
1154 * clients.
1155 */
Ben Lindstrombba81212001-06-25 05:01:22 +00001156static void
Damien Millerb38eff82000-04-01 11:09:21 +10001157channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset)
1158{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001159 Channel *nc;
Ben Lindstrome9c99912001-06-09 00:41:05 +00001160 char *name;
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001161 int newsock;
Damien Millerb38eff82000-04-01 11:09:21 +10001162 struct sockaddr addr;
Damien Millerb38eff82000-04-01 11:09:21 +10001163 socklen_t addrlen;
1164
1165 if (FD_ISSET(c->sock, readset)) {
1166 addrlen = sizeof(addr);
1167 newsock = accept(c->sock, &addr, &addrlen);
1168 if (newsock < 0) {
1169 error("accept from auth socket: %.100s", strerror(errno));
1170 return;
1171 }
Ben Lindstrome9c99912001-06-09 00:41:05 +00001172 name = xstrdup("accepted auth socket");
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001173 nc = channel_new("accepted auth socket",
Damien Miller0bc1bd82000-11-13 22:57:25 +11001174 SSH_CHANNEL_OPENING, newsock, newsock, -1,
1175 c->local_window_max, c->local_maxpacket,
Ben Lindstrome9c99912001-06-09 00:41:05 +00001176 0, name, 1);
Damien Miller0bc1bd82000-11-13 22:57:25 +11001177 if (compat20) {
1178 packet_start(SSH2_MSG_CHANNEL_OPEN);
1179 packet_put_cstring("auth-agent@openssh.com");
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001180 packet_put_int(nc->self);
Damien Miller0bc1bd82000-11-13 22:57:25 +11001181 packet_put_int(c->local_window_max);
1182 packet_put_int(c->local_maxpacket);
1183 } else {
1184 packet_start(SSH_SMSG_AGENT_OPEN);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001185 packet_put_int(nc->self);
Damien Miller0bc1bd82000-11-13 22:57:25 +11001186 }
Damien Millerb38eff82000-04-01 11:09:21 +10001187 packet_send();
1188 }
1189}
1190
Ben Lindstrombba81212001-06-25 05:01:22 +00001191static void
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001192channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset)
1193{
Ben Lindstrom69128662001-05-08 20:07:39 +00001194 int err = 0;
Ben Lindstrom11180952001-07-04 05:13:35 +00001195 socklen_t sz = sizeof(err);
Ben Lindstrom69128662001-05-08 20:07:39 +00001196
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001197 if (FD_ISSET(c->sock, writeset)) {
Ben Lindstrom733a2352002-03-05 01:31:28 +00001198 if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
Ben Lindstrom69128662001-05-08 20:07:39 +00001199 err = errno;
1200 error("getsockopt SO_ERROR failed");
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001201 }
Ben Lindstrom69128662001-05-08 20:07:39 +00001202 if (err == 0) {
1203 debug("channel %d: connected", c->self);
1204 c->type = SSH_CHANNEL_OPEN;
1205 if (compat20) {
1206 packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1207 packet_put_int(c->remote_id);
1208 packet_put_int(c->self);
1209 packet_put_int(c->local_window);
1210 packet_put_int(c->local_maxpacket);
1211 } else {
1212 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1213 packet_put_int(c->remote_id);
1214 packet_put_int(c->self);
1215 }
1216 } else {
1217 debug("channel %d: not connected: %s",
1218 c->self, strerror(err));
1219 if (compat20) {
1220 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1221 packet_put_int(c->remote_id);
1222 packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1223 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1224 packet_put_cstring(strerror(err));
1225 packet_put_cstring("");
1226 }
1227 } else {
1228 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1229 packet_put_int(c->remote_id);
1230 }
1231 chan_mark_dead(c);
1232 }
1233 packet_send();
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001234 }
1235}
1236
Ben Lindstrombba81212001-06-25 05:01:22 +00001237static int
Damien Millerb38eff82000-04-01 11:09:21 +10001238channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset)
1239{
1240 char buf[16*1024];
1241 int len;
1242
Ben Lindstromc0dee1a2001-06-05 20:52:50 +00001243 if (c->rfd != -1 &&
Damien Millerb38eff82000-04-01 11:09:21 +10001244 FD_ISSET(c->rfd, readset)) {
1245 len = read(c->rfd, buf, sizeof(buf));
Damien Miller6f83b8e2000-05-02 09:23:45 +10001246 if (len < 0 && (errno == EINTR || errno == EAGAIN))
1247 return 1;
Damien Millerb38eff82000-04-01 11:09:21 +10001248 if (len <= 0) {
Damien Millerbd483e72000-04-30 10:00:53 +10001249 debug("channel %d: read<=0 rfd %d len %d",
Damien Millerb38eff82000-04-01 11:09:21 +10001250 c->self, c->rfd, len);
Ben Lindstromb3921512001-04-11 15:57:50 +00001251 if (c->type != SSH_CHANNEL_OPEN) {
1252 debug("channel %d: not open", c->self);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001253 chan_mark_dead(c);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001254 return -1;
Ben Lindstromb3921512001-04-11 15:57:50 +00001255 } else if (compat13) {
Damien Miller76765c02002-01-22 23:21:15 +11001256 buffer_clear(&c->output);
Damien Millerb38eff82000-04-01 11:09:21 +10001257 c->type = SSH_CHANNEL_INPUT_DRAINING;
Ben Lindstrome9c99912001-06-09 00:41:05 +00001258 debug("channel %d: input draining.", c->self);
Damien Millerb38eff82000-04-01 11:09:21 +10001259 } else {
1260 chan_read_failed(c);
1261 }
1262 return -1;
1263 }
Ben Lindstrom1c37c6a2001-12-06 18:00:18 +00001264 if (c->input_filter != NULL) {
Damien Millerad833b32000-08-23 10:46:23 +10001265 if (c->input_filter(c, buf, len) == -1) {
Ben Lindstromc486d882001-04-11 16:08:34 +00001266 debug("channel %d: filter stops", c->self);
Damien Millerad833b32000-08-23 10:46:23 +10001267 chan_read_failed(c);
1268 }
1269 } else {
1270 buffer_append(&c->input, buf, len);
1271 }
Damien Millerb38eff82000-04-01 11:09:21 +10001272 }
1273 return 1;
1274}
Ben Lindstrombba81212001-06-25 05:01:22 +00001275static int
Damien Millerb38eff82000-04-01 11:09:21 +10001276channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset)
1277{
Ben Lindstrome229b252001-03-05 06:28:06 +00001278 struct termios tio;
Ben Lindstrom6d218f42001-09-18 05:53:12 +00001279 u_char *data;
1280 u_int dlen;
Damien Millerb38eff82000-04-01 11:09:21 +10001281 int len;
1282
1283 /* Send buffered output data to the socket. */
Ben Lindstromc0dee1a2001-06-05 20:52:50 +00001284 if (c->wfd != -1 &&
Damien Millerb38eff82000-04-01 11:09:21 +10001285 FD_ISSET(c->wfd, writeset) &&
1286 buffer_len(&c->output) > 0) {
Ben Lindstrom6d218f42001-09-18 05:53:12 +00001287 data = buffer_ptr(&c->output);
1288 dlen = buffer_len(&c->output);
1289 len = write(c->wfd, data, dlen);
Ben Lindstrom92ea0ea2002-07-04 18:11:09 +00001290#ifdef _AIX
1291 /* XXX: Later AIX versions can't push as much data to tty */
1292 if (compat20 && c->isatty && dlen >= 8*1024)
1293 dlen = 8*1024;
1294#endif
Damien Miller6f83b8e2000-05-02 09:23:45 +10001295 if (len < 0 && (errno == EINTR || errno == EAGAIN))
1296 return 1;
Damien Millerb38eff82000-04-01 11:09:21 +10001297 if (len <= 0) {
Ben Lindstromb3921512001-04-11 15:57:50 +00001298 if (c->type != SSH_CHANNEL_OPEN) {
1299 debug("channel %d: not open", c->self);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001300 chan_mark_dead(c);
Ben Lindstromb3921512001-04-11 15:57:50 +00001301 return -1;
1302 } else if (compat13) {
Damien Miller76765c02002-01-22 23:21:15 +11001303 buffer_clear(&c->output);
Ben Lindstrome9c99912001-06-09 00:41:05 +00001304 debug("channel %d: input draining.", c->self);
Damien Millerb38eff82000-04-01 11:09:21 +10001305 c->type = SSH_CHANNEL_INPUT_DRAINING;
1306 } else {
1307 chan_write_failed(c);
1308 }
1309 return -1;
1310 }
Ben Lindstrom6d218f42001-09-18 05:53:12 +00001311 if (compat20 && c->isatty && dlen >= 1 && data[0] != '\r') {
Damien Miller79438cc2001-02-16 12:34:57 +11001312 if (tcgetattr(c->wfd, &tio) == 0 &&
1313 !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1314 /*
1315 * Simulate echo to reduce the impact of
Ben Lindstromb40204b2001-03-05 06:29:44 +00001316 * traffic analysis. We need to match the
Ben Lindstrome229b252001-03-05 06:28:06 +00001317 * size of a SSH2_MSG_CHANNEL_DATA message
1318 * (4 byte channel id + data)
Damien Miller79438cc2001-02-16 12:34:57 +11001319 */
Ben Lindstrome229b252001-03-05 06:28:06 +00001320 packet_send_ignore(4 + len);
Damien Miller79438cc2001-02-16 12:34:57 +11001321 packet_send();
Damien Miller79438cc2001-02-16 12:34:57 +11001322 }
1323 }
Damien Millerb38eff82000-04-01 11:09:21 +10001324 buffer_consume(&c->output, len);
Damien Miller33b13562000-04-04 14:38:59 +10001325 if (compat20 && len > 0) {
1326 c->local_consumed += len;
1327 }
1328 }
1329 return 1;
1330}
Ben Lindstrombba81212001-06-25 05:01:22 +00001331static int
Damien Miller33b13562000-04-04 14:38:59 +10001332channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset)
1333{
1334 char buf[16*1024];
1335 int len;
1336
Damien Miller1383bd82000-04-06 12:32:37 +10001337/** XXX handle drain efd, too */
Damien Miller33b13562000-04-04 14:38:59 +10001338 if (c->efd != -1) {
1339 if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1340 FD_ISSET(c->efd, writeset) &&
1341 buffer_len(&c->extended) > 0) {
1342 len = write(c->efd, buffer_ptr(&c->extended),
1343 buffer_len(&c->extended));
Damien Millerd3444942000-09-30 14:20:03 +11001344 debug2("channel %d: written %d to efd %d",
Damien Miller33b13562000-04-04 14:38:59 +10001345 c->self, len, c->efd);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001346 if (len < 0 && (errno == EINTR || errno == EAGAIN))
1347 return 1;
1348 if (len <= 0) {
1349 debug2("channel %d: closing write-efd %d",
1350 c->self, c->efd);
Ben Lindstrom16d29d52001-07-18 16:01:46 +00001351 channel_close_fd(&c->efd);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001352 } else {
Damien Miller33b13562000-04-04 14:38:59 +10001353 buffer_consume(&c->extended, len);
1354 c->local_consumed += len;
1355 }
1356 } else if (c->extended_usage == CHAN_EXTENDED_READ &&
1357 FD_ISSET(c->efd, readset)) {
1358 len = read(c->efd, buf, sizeof(buf));
Damien Millerd3444942000-09-30 14:20:03 +11001359 debug2("channel %d: read %d from efd %d",
Damien Miller9f0f5c62001-12-21 14:45:46 +11001360 c->self, len, c->efd);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001361 if (len < 0 && (errno == EINTR || errno == EAGAIN))
1362 return 1;
1363 if (len <= 0) {
1364 debug2("channel %d: closing read-efd %d",
Damien Miller1383bd82000-04-06 12:32:37 +10001365 c->self, c->efd);
Ben Lindstrom16d29d52001-07-18 16:01:46 +00001366 channel_close_fd(&c->efd);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001367 } else {
Damien Miller33b13562000-04-04 14:38:59 +10001368 buffer_append(&c->extended, buf, len);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001369 }
Damien Miller33b13562000-04-04 14:38:59 +10001370 }
1371 }
1372 return 1;
1373}
Ben Lindstrombba81212001-06-25 05:01:22 +00001374static int
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001375channel_check_window(Channel *c)
Damien Miller33b13562000-04-04 14:38:59 +10001376{
Ben Lindstromb3921512001-04-11 15:57:50 +00001377 if (c->type == SSH_CHANNEL_OPEN &&
1378 !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
Damien Miller33b13562000-04-04 14:38:59 +10001379 c->local_window < c->local_window_max/2 &&
1380 c->local_consumed > 0) {
1381 packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1382 packet_put_int(c->remote_id);
1383 packet_put_int(c->local_consumed);
1384 packet_send();
Damien Millerd3444942000-09-30 14:20:03 +11001385 debug2("channel %d: window %d sent adjust %d",
Damien Miller33b13562000-04-04 14:38:59 +10001386 c->self, c->local_window,
1387 c->local_consumed);
1388 c->local_window += c->local_consumed;
1389 c->local_consumed = 0;
Damien Millerb38eff82000-04-01 11:09:21 +10001390 }
1391 return 1;
1392}
1393
Ben Lindstrombba81212001-06-25 05:01:22 +00001394static void
Damien Millerde6987c2002-01-22 23:20:40 +11001395channel_post_open(Channel *c, fd_set * readset, fd_set * writeset)
Damien Millerb38eff82000-04-01 11:09:21 +10001396{
Damien Miller4623a752001-10-10 15:03:58 +10001397 if (c->delayed)
1398 return;
Damien Millerb38eff82000-04-01 11:09:21 +10001399 channel_handle_rfd(c, readset, writeset);
1400 channel_handle_wfd(c, readset, writeset);
Damien Millerde6987c2002-01-22 23:20:40 +11001401 if (!compat20)
Damien Miller4623a752001-10-10 15:03:58 +10001402 return;
Damien Miller33b13562000-04-04 14:38:59 +10001403 channel_handle_efd(c, readset, writeset);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001404 channel_check_window(c);
Damien Miller33b13562000-04-04 14:38:59 +10001405}
1406
Ben Lindstrombba81212001-06-25 05:01:22 +00001407static void
Damien Millerb38eff82000-04-01 11:09:21 +10001408channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset)
1409{
1410 int len;
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +00001411
Damien Millerb38eff82000-04-01 11:09:21 +10001412 /* Send buffered output data to the socket. */
1413 if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
1414 len = write(c->sock, buffer_ptr(&c->output),
1415 buffer_len(&c->output));
1416 if (len <= 0)
Damien Miller76765c02002-01-22 23:21:15 +11001417 buffer_clear(&c->output);
Damien Millerb38eff82000-04-01 11:09:21 +10001418 else
1419 buffer_consume(&c->output, len);
1420 }
1421}
1422
Ben Lindstrombba81212001-06-25 05:01:22 +00001423static void
Damien Miller33b13562000-04-04 14:38:59 +10001424channel_handler_init_20(void)
1425{
Damien Millerde6987c2002-01-22 23:20:40 +11001426 channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
Damien Millerbd483e72000-04-30 10:00:53 +10001427 channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
Damien Miller33b13562000-04-04 14:38:59 +10001428 channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
Damien Miller0bc1bd82000-11-13 22:57:25 +11001429 channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
Damien Millerbd483e72000-04-30 10:00:53 +10001430 channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
Damien Miller0bc1bd82000-11-13 22:57:25 +11001431 channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001432 channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001433 channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
Damien Miller33b13562000-04-04 14:38:59 +10001434
Damien Millerde6987c2002-01-22 23:20:40 +11001435 channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
Damien Miller33b13562000-04-04 14:38:59 +10001436 channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
Damien Miller0bc1bd82000-11-13 22:57:25 +11001437 channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
Damien Millerbd483e72000-04-30 10:00:53 +10001438 channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
Damien Miller0bc1bd82000-11-13 22:57:25 +11001439 channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001440 channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
Damien Millerde6987c2002-01-22 23:20:40 +11001441 channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
Damien Miller33b13562000-04-04 14:38:59 +10001442}
1443
Ben Lindstrombba81212001-06-25 05:01:22 +00001444static void
Damien Millerb38eff82000-04-01 11:09:21 +10001445channel_handler_init_13(void)
1446{
1447 channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
1448 channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
1449 channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1450 channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1451 channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1452 channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
1453 channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001454 channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001455 channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
Damien Millerb38eff82000-04-01 11:09:21 +10001456
Damien Millerde6987c2002-01-22 23:20:40 +11001457 channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
Damien Millerb38eff82000-04-01 11:09:21 +10001458 channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1459 channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1460 channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1461 channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001462 channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
Damien Millerde6987c2002-01-22 23:20:40 +11001463 channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
Damien Millerb38eff82000-04-01 11:09:21 +10001464}
1465
Ben Lindstrombba81212001-06-25 05:01:22 +00001466static void
Damien Millerb38eff82000-04-01 11:09:21 +10001467channel_handler_init_15(void)
1468{
Damien Millerde6987c2002-01-22 23:20:40 +11001469 channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
Damien Millerbd483e72000-04-30 10:00:53 +10001470 channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
Damien Millerb38eff82000-04-01 11:09:21 +10001471 channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1472 channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1473 channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001474 channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001475 channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
Damien Millerb38eff82000-04-01 11:09:21 +10001476
1477 channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1478 channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1479 channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
Damien Millerde6987c2002-01-22 23:20:40 +11001480 channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001481 channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
Damien Millerde6987c2002-01-22 23:20:40 +11001482 channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
Damien Millerb38eff82000-04-01 11:09:21 +10001483}
1484
Ben Lindstrombba81212001-06-25 05:01:22 +00001485static void
Damien Millerb38eff82000-04-01 11:09:21 +10001486channel_handler_init(void)
1487{
1488 int i;
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +00001489
Damien Miller9f0f5c62001-12-21 14:45:46 +11001490 for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
Damien Millerb38eff82000-04-01 11:09:21 +10001491 channel_pre[i] = NULL;
1492 channel_post[i] = NULL;
1493 }
Damien Miller33b13562000-04-04 14:38:59 +10001494 if (compat20)
1495 channel_handler_init_20();
1496 else if (compat13)
Damien Millerb38eff82000-04-01 11:09:21 +10001497 channel_handler_init_13();
1498 else
1499 channel_handler_init_15();
1500}
1501
Damien Miller3ec27592001-10-12 11:35:04 +10001502/* gc dead channels */
1503static void
1504channel_garbage_collect(Channel *c)
1505{
1506 if (c == NULL)
1507 return;
1508 if (c->detach_user != NULL) {
1509 if (!chan_is_dead(c, 0))
1510 return;
1511 debug("channel %d: gc: notify user", c->self);
1512 c->detach_user(c->self, NULL);
1513 /* if we still have a callback */
1514 if (c->detach_user != NULL)
1515 return;
1516 debug("channel %d: gc: user detached", c->self);
1517 }
1518 if (!chan_is_dead(c, 1))
1519 return;
1520 debug("channel %d: garbage collecting", c->self);
1521 channel_free(c);
1522}
1523
Ben Lindstrombba81212001-06-25 05:01:22 +00001524static void
Damien Millerb38eff82000-04-01 11:09:21 +10001525channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset)
1526{
1527 static int did_init = 0;
1528 int i;
1529 Channel *c;
1530
1531 if (!did_init) {
1532 channel_handler_init();
1533 did_init = 1;
1534 }
1535 for (i = 0; i < channels_alloc; i++) {
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001536 c = channels[i];
1537 if (c == NULL)
Damien Millerb38eff82000-04-01 11:09:21 +10001538 continue;
Ben Lindstromc0dee1a2001-06-05 20:52:50 +00001539 if (ftab[c->type] != NULL)
1540 (*ftab[c->type])(c, readset, writeset);
Damien Miller3ec27592001-10-12 11:35:04 +10001541 channel_garbage_collect(c);
Damien Millerb38eff82000-04-01 11:09:21 +10001542 }
1543}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001544
Ben Lindstrome9c99912001-06-09 00:41:05 +00001545/*
1546 * Allocate/update select bitmasks and add any bits relevant to channels in
1547 * select bitmasks.
1548 */
Damien Miller4af51302000-04-16 11:18:38 +10001549void
Ben Lindstrombe2cc432001-04-04 23:46:07 +00001550channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
Ben Lindstrom16d29d52001-07-18 16:01:46 +00001551 int *nallocp, int rekeying)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001552{
Damien Miller5e953212001-01-30 09:14:00 +11001553 int n;
1554 u_int sz;
1555
1556 n = MAX(*maxfdp, channel_max_fd);
1557
1558 sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
Ben Lindstrom16d29d52001-07-18 16:01:46 +00001559 /* perhaps check sz < nalloc/2 and shrink? */
1560 if (*readsetp == NULL || sz > *nallocp) {
1561 *readsetp = xrealloc(*readsetp, sz);
1562 *writesetp = xrealloc(*writesetp, sz);
1563 *nallocp = sz;
Damien Miller5e953212001-01-30 09:14:00 +11001564 }
Ben Lindstrom16d29d52001-07-18 16:01:46 +00001565 *maxfdp = n;
Damien Miller5e953212001-01-30 09:14:00 +11001566 memset(*readsetp, 0, sz);
1567 memset(*writesetp, 0, sz);
1568
Ben Lindstrombe2cc432001-04-04 23:46:07 +00001569 if (!rekeying)
1570 channel_handler(channel_pre, *readsetp, *writesetp);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001571}
1572
Ben Lindstrome9c99912001-06-09 00:41:05 +00001573/*
1574 * After select, perform any appropriate operations for channels which have
1575 * events pending.
1576 */
Damien Miller4af51302000-04-16 11:18:38 +10001577void
Damien Miller95def091999-11-25 00:26:21 +11001578channel_after_select(fd_set * readset, fd_set * writeset)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001579{
Damien Millerb38eff82000-04-01 11:09:21 +10001580 channel_handler(channel_post, readset, writeset);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001581}
1582
Ben Lindstrome9c99912001-06-09 00:41:05 +00001583
Damien Miller5e953212001-01-30 09:14:00 +11001584/* If there is data to send to the connection, enqueue some of it now. */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001585
Damien Miller4af51302000-04-16 11:18:38 +10001586void
Ben Lindstrom3c36bb22001-12-06 17:55:26 +00001587channel_output_poll(void)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001588{
Damien Millerb38eff82000-04-01 11:09:21 +10001589 Channel *c;
Ben Lindstrom4fed2be2002-06-25 23:17:36 +00001590 int i;
1591 u_int len;
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? */
Damien Miller3ec27592001-10-12 11:35:04 +10001613 debug3("channel %d: will not send 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:
Ben Lindstromcf159442002-03-26 03:26:24 +00001654 * tell peer, that we will not send more data: send IEOF.
1655 * hack for extended data: delay EOF if EFD still in use.
Damien Miller5428f641999-11-25 11:54:57 +11001656 */
Ben Lindstromcf159442002-03-26 03:26:24 +00001657 if (CHANNEL_EFD_INPUT_ACTIVE(c))
Ben Lindstrom5a6abda2002-06-09 19:41:48 +00001658 debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
1659 c->self, c->efd, buffer_len(&c->extended));
Ben Lindstromcf159442002-03-26 03:26:24 +00001660 else
1661 chan_ibuf_empty(c);
Damien Miller95def091999-11-25 00:26:21 +11001662 }
Damien Miller33b13562000-04-04 14:38:59 +10001663 /* Send extended data, i.e. stderr */
1664 if (compat20 &&
Ben Lindstromcf159442002-03-26 03:26:24 +00001665 !(c->flags & CHAN_EOF_SENT) &&
Damien Miller33b13562000-04-04 14:38:59 +10001666 c->remote_window > 0 &&
1667 (len = buffer_len(&c->extended)) > 0 &&
1668 c->extended_usage == CHAN_EXTENDED_READ) {
Ben Lindstrom4fed2be2002-06-25 23:17:36 +00001669 debug2("channel %d: rwin %u elen %u euse %d",
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001670 c->self, c->remote_window, buffer_len(&c->extended),
1671 c->extended_usage);
Damien Miller33b13562000-04-04 14:38:59 +10001672 if (len > c->remote_window)
1673 len = c->remote_window;
1674 if (len > c->remote_maxpacket)
1675 len = c->remote_maxpacket;
1676 packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
1677 packet_put_int(c->remote_id);
1678 packet_put_int(SSH2_EXTENDED_DATA_STDERR);
1679 packet_put_string(buffer_ptr(&c->extended), len);
1680 packet_send();
1681 buffer_consume(&c->extended, len);
1682 c->remote_window -= len;
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001683 debug2("channel %d: sent ext data %d", c->self, len);
Damien Miller33b13562000-04-04 14:38:59 +10001684 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001685 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001686}
1687
Ben Lindstrome9c99912001-06-09 00:41:05 +00001688
1689/* -- protocol input */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001690
Damien Miller4af51302000-04-16 11:18:38 +10001691void
Damien Miller630d6f42002-01-22 23:17:30 +11001692channel_input_data(int type, u_int32_t seq, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001693{
Damien Miller34132e52000-01-14 15:45:46 +11001694 int id;
Damien Miller95def091999-11-25 00:26:21 +11001695 char *data;
Ben Lindstrom46c16222000-12-22 01:43:59 +00001696 u_int data_len;
Damien Millerb38eff82000-04-01 11:09:21 +10001697 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001698
Damien Miller95def091999-11-25 00:26:21 +11001699 /* Get the channel number and verify it. */
Damien Miller34132e52000-01-14 15:45:46 +11001700 id = packet_get_int();
Damien Millerb38eff82000-04-01 11:09:21 +10001701 c = channel_lookup(id);
1702 if (c == NULL)
Damien Miller34132e52000-01-14 15:45:46 +11001703 packet_disconnect("Received data for nonexistent channel %d.", id);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001704
Damien Miller95def091999-11-25 00:26:21 +11001705 /* Ignore any data for non-open channels (might happen on close) */
Damien Millerb38eff82000-04-01 11:09:21 +10001706 if (c->type != SSH_CHANNEL_OPEN &&
1707 c->type != SSH_CHANNEL_X11_OPEN)
Damien Miller34132e52000-01-14 15:45:46 +11001708 return;
1709
1710 /* same for protocol 1.5 if output end is no longer open */
Damien Millerb38eff82000-04-01 11:09:21 +10001711 if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN)
Damien Miller95def091999-11-25 00:26:21 +11001712 return;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001713
Damien Miller95def091999-11-25 00:26:21 +11001714 /* Get the data. */
1715 data = packet_get_string(&data_len);
Damien Millerb38eff82000-04-01 11:09:21 +10001716
Ben Lindstrom1c37c6a2001-12-06 18:00:18 +00001717 if (compat20) {
Damien Miller33b13562000-04-04 14:38:59 +10001718 if (data_len > c->local_maxpacket) {
1719 log("channel %d: rcvd big packet %d, maxpack %d",
1720 c->self, data_len, c->local_maxpacket);
1721 }
1722 if (data_len > c->local_window) {
1723 log("channel %d: rcvd too much data %d, win %d",
1724 c->self, data_len, c->local_window);
1725 xfree(data);
1726 return;
1727 }
1728 c->local_window -= data_len;
Damien Miller33b13562000-04-04 14:38:59 +10001729 }
Damien Miller48b03fc2002-01-22 23:11:40 +11001730 packet_check_eom();
Damien Millerb38eff82000-04-01 11:09:21 +10001731 buffer_append(&c->output, data, data_len);
Damien Miller95def091999-11-25 00:26:21 +11001732 xfree(data);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001733}
Ben Lindstrome9c99912001-06-09 00:41:05 +00001734
Damien Miller4af51302000-04-16 11:18:38 +10001735void
Damien Miller630d6f42002-01-22 23:17:30 +11001736channel_input_extended_data(int type, u_int32_t seq, void *ctxt)
Damien Miller33b13562000-04-04 14:38:59 +10001737{
1738 int id;
Damien Miller33b13562000-04-04 14:38:59 +10001739 char *data;
Ben Lindstromdaa21792002-06-25 23:15:30 +00001740 u_int data_len, tcode;
Damien Miller33b13562000-04-04 14:38:59 +10001741 Channel *c;
1742
1743 /* Get the channel number and verify it. */
1744 id = packet_get_int();
1745 c = channel_lookup(id);
1746
1747 if (c == NULL)
1748 packet_disconnect("Received extended_data for bad channel %d.", id);
1749 if (c->type != SSH_CHANNEL_OPEN) {
1750 log("channel %d: ext data for non open", id);
1751 return;
1752 }
Ben Lindstromcf159442002-03-26 03:26:24 +00001753 if (c->flags & CHAN_EOF_RCVD) {
1754 if (datafellows & SSH_BUG_EXTEOF)
1755 debug("channel %d: accepting ext data after eof", id);
1756 else
1757 packet_disconnect("Received extended_data after EOF "
1758 "on channel %d.", id);
1759 }
Damien Miller33b13562000-04-04 14:38:59 +10001760 tcode = packet_get_int();
1761 if (c->efd == -1 ||
1762 c->extended_usage != CHAN_EXTENDED_WRITE ||
1763 tcode != SSH2_EXTENDED_DATA_STDERR) {
1764 log("channel %d: bad ext data", c->self);
1765 return;
1766 }
1767 data = packet_get_string(&data_len);
Damien Miller48b03fc2002-01-22 23:11:40 +11001768 packet_check_eom();
Damien Miller33b13562000-04-04 14:38:59 +10001769 if (data_len > c->local_window) {
1770 log("channel %d: rcvd too much extended_data %d, win %d",
1771 c->self, data_len, c->local_window);
1772 xfree(data);
1773 return;
1774 }
Damien Millerd3444942000-09-30 14:20:03 +11001775 debug2("channel %d: rcvd ext data %d", c->self, data_len);
Damien Miller33b13562000-04-04 14:38:59 +10001776 c->local_window -= data_len;
1777 buffer_append(&c->extended, data, data_len);
1778 xfree(data);
1779}
1780
Damien Miller4af51302000-04-16 11:18:38 +10001781void
Damien Miller630d6f42002-01-22 23:17:30 +11001782channel_input_ieof(int type, u_int32_t seq, void *ctxt)
Damien Millerb38eff82000-04-01 11:09:21 +10001783{
1784 int id;
1785 Channel *c;
1786
Damien Millerb38eff82000-04-01 11:09:21 +10001787 id = packet_get_int();
Damien Miller48b03fc2002-01-22 23:11:40 +11001788 packet_check_eom();
Damien Millerb38eff82000-04-01 11:09:21 +10001789 c = channel_lookup(id);
1790 if (c == NULL)
1791 packet_disconnect("Received ieof for nonexistent channel %d.", id);
1792 chan_rcvd_ieof(c);
Ben Lindstrom944c4f02001-09-18 05:51:13 +00001793
1794 /* XXX force input close */
Damien Millera90fc082002-01-22 23:19:38 +11001795 if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
Ben Lindstrom944c4f02001-09-18 05:51:13 +00001796 debug("channel %d: FORCE input drain", c->self);
1797 c->istate = CHAN_INPUT_WAIT_DRAIN;
Damien Miller73f10742002-01-22 23:34:52 +11001798 if (buffer_len(&c->input) == 0)
1799 chan_ibuf_empty(c);
Ben Lindstrom944c4f02001-09-18 05:51:13 +00001800 }
1801
Damien Millerb38eff82000-04-01 11:09:21 +10001802}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001803
Damien Miller4af51302000-04-16 11:18:38 +10001804void
Damien Miller630d6f42002-01-22 23:17:30 +11001805channel_input_close(int type, u_int32_t seq, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001806{
Damien Millerb38eff82000-04-01 11:09:21 +10001807 int id;
1808 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001809
Damien Millerb38eff82000-04-01 11:09:21 +10001810 id = packet_get_int();
Damien Miller48b03fc2002-01-22 23:11:40 +11001811 packet_check_eom();
Damien Millerb38eff82000-04-01 11:09:21 +10001812 c = channel_lookup(id);
1813 if (c == NULL)
1814 packet_disconnect("Received close for nonexistent channel %d.", id);
Damien Miller5428f641999-11-25 11:54:57 +11001815
1816 /*
1817 * Send a confirmation that we have closed the channel and no more
1818 * data is coming for it.
1819 */
Damien Miller95def091999-11-25 00:26:21 +11001820 packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
Damien Millerb38eff82000-04-01 11:09:21 +10001821 packet_put_int(c->remote_id);
Damien Miller95def091999-11-25 00:26:21 +11001822 packet_send();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001823
Damien Miller5428f641999-11-25 11:54:57 +11001824 /*
1825 * If the channel is in closed state, we have sent a close request,
1826 * and the other side will eventually respond with a confirmation.
1827 * Thus, we cannot free the channel here, because then there would be
1828 * no-one to receive the confirmation. The channel gets freed when
1829 * the confirmation arrives.
1830 */
Damien Millerb38eff82000-04-01 11:09:21 +10001831 if (c->type != SSH_CHANNEL_CLOSED) {
Damien Miller5428f641999-11-25 11:54:57 +11001832 /*
1833 * Not a closed channel - mark it as draining, which will
1834 * cause it to be freed later.
1835 */
Damien Miller76765c02002-01-22 23:21:15 +11001836 buffer_clear(&c->input);
Damien Millerb38eff82000-04-01 11:09:21 +10001837 c->type = SSH_CHANNEL_OUTPUT_DRAINING;
Damien Miller95def091999-11-25 00:26:21 +11001838 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001839}
1840
Damien Millerb38eff82000-04-01 11:09:21 +10001841/* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
Damien Miller4af51302000-04-16 11:18:38 +10001842void
Damien Miller630d6f42002-01-22 23:17:30 +11001843channel_input_oclose(int type, u_int32_t seq, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001844{
Damien Millerb38eff82000-04-01 11:09:21 +10001845 int id = packet_get_int();
1846 Channel *c = channel_lookup(id);
Damien Miller66823cd2002-01-22 23:11:38 +11001847
Damien Miller48b03fc2002-01-22 23:11:40 +11001848 packet_check_eom();
Damien Millerb38eff82000-04-01 11:09:21 +10001849 if (c == NULL)
1850 packet_disconnect("Received oclose for nonexistent channel %d.", id);
1851 chan_rcvd_oclose(c);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001852}
1853
Damien Miller4af51302000-04-16 11:18:38 +10001854void
Damien Miller630d6f42002-01-22 23:17:30 +11001855channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt)
Damien Millerb38eff82000-04-01 11:09:21 +10001856{
1857 int id = packet_get_int();
1858 Channel *c = channel_lookup(id);
1859
Damien Miller48b03fc2002-01-22 23:11:40 +11001860 packet_check_eom();
Damien Millerb38eff82000-04-01 11:09:21 +10001861 if (c == NULL)
1862 packet_disconnect("Received close confirmation for "
1863 "out-of-range channel %d.", id);
1864 if (c->type != SSH_CHANNEL_CLOSED)
1865 packet_disconnect("Received close confirmation for "
1866 "non-closed channel %d (type %d).", id, c->type);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001867 channel_free(c);
Damien Millerb38eff82000-04-01 11:09:21 +10001868}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001869
Damien Miller4af51302000-04-16 11:18:38 +10001870void
Damien Miller630d6f42002-01-22 23:17:30 +11001871channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001872{
Damien Millerb38eff82000-04-01 11:09:21 +10001873 int id, remote_id;
1874 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001875
Damien Millerb38eff82000-04-01 11:09:21 +10001876 id = packet_get_int();
1877 c = channel_lookup(id);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001878
Damien Millerb38eff82000-04-01 11:09:21 +10001879 if (c==NULL || c->type != SSH_CHANNEL_OPENING)
1880 packet_disconnect("Received open confirmation for "
1881 "non-opening channel %d.", id);
1882 remote_id = packet_get_int();
Damien Miller5428f641999-11-25 11:54:57 +11001883 /* Record the remote channel number and mark that the channel is now open. */
Damien Millerb38eff82000-04-01 11:09:21 +10001884 c->remote_id = remote_id;
1885 c->type = SSH_CHANNEL_OPEN;
Damien Miller33b13562000-04-04 14:38:59 +10001886
1887 if (compat20) {
1888 c->remote_window = packet_get_int();
1889 c->remote_maxpacket = packet_get_int();
Damien Miller67f0bc02002-02-05 12:23:08 +11001890 if (c->confirm) {
Damien Millerd3444942000-09-30 14:20:03 +11001891 debug2("callback start");
Damien Miller67f0bc02002-02-05 12:23:08 +11001892 c->confirm(c->self, NULL);
Damien Millerd3444942000-09-30 14:20:03 +11001893 debug2("callback done");
Damien Miller33b13562000-04-04 14:38:59 +10001894 }
Ben Lindstrom4fed2be2002-06-25 23:17:36 +00001895 debug("channel %d: open confirm rwindow %u rmax %u", c->self,
Damien Miller33b13562000-04-04 14:38:59 +10001896 c->remote_window, c->remote_maxpacket);
1897 }
Damien Miller48b03fc2002-01-22 23:11:40 +11001898 packet_check_eom();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001899}
1900
Ben Lindstrombba81212001-06-25 05:01:22 +00001901static char *
Ben Lindstrom69128662001-05-08 20:07:39 +00001902reason2txt(int reason)
1903{
Ben Lindstrom1c37c6a2001-12-06 18:00:18 +00001904 switch (reason) {
Ben Lindstrom69128662001-05-08 20:07:39 +00001905 case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
1906 return "administratively prohibited";
1907 case SSH2_OPEN_CONNECT_FAILED:
1908 return "connect failed";
1909 case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
1910 return "unknown channel type";
1911 case SSH2_OPEN_RESOURCE_SHORTAGE:
1912 return "resource shortage";
1913 }
Ben Lindstrome2595442001-06-05 20:01:39 +00001914 return "unknown reason";
Ben Lindstrom69128662001-05-08 20:07:39 +00001915}
1916
Damien Miller4af51302000-04-16 11:18:38 +10001917void
Damien Miller630d6f42002-01-22 23:17:30 +11001918channel_input_open_failure(int type, u_int32_t seq, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001919{
Kevin Steves12057502001-02-05 14:54:34 +00001920 int id, reason;
1921 char *msg = NULL, *lang = NULL;
Damien Millerb38eff82000-04-01 11:09:21 +10001922 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001923
Damien Millerb38eff82000-04-01 11:09:21 +10001924 id = packet_get_int();
1925 c = channel_lookup(id);
1926
1927 if (c==NULL || c->type != SSH_CHANNEL_OPENING)
1928 packet_disconnect("Received open failure for "
1929 "non-opening channel %d.", id);
Damien Miller33b13562000-04-04 14:38:59 +10001930 if (compat20) {
Kevin Steves12057502001-02-05 14:54:34 +00001931 reason = packet_get_int();
Ben Lindstromf3436742001-04-29 19:52:00 +00001932 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
Kevin Steves12057502001-02-05 14:54:34 +00001933 msg = packet_get_string(NULL);
1934 lang = packet_get_string(NULL);
1935 }
Ben Lindstrom69128662001-05-08 20:07:39 +00001936 log("channel %d: open failed: %s%s%s", id,
1937 reason2txt(reason), msg ? ": ": "", msg ? msg : "");
Kevin Steves12057502001-02-05 14:54:34 +00001938 if (msg != NULL)
1939 xfree(msg);
1940 if (lang != NULL)
1941 xfree(lang);
Damien Miller33b13562000-04-04 14:38:59 +10001942 }
Damien Miller48b03fc2002-01-22 23:11:40 +11001943 packet_check_eom();
Damien Miller95def091999-11-25 00:26:21 +11001944 /* Free the channel. This will also close the socket. */
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001945 channel_free(c);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001946}
1947
Damien Miller33b13562000-04-04 14:38:59 +10001948void
Damien Miller630d6f42002-01-22 23:17:30 +11001949channel_input_window_adjust(int type, u_int32_t seq, void *ctxt)
Damien Miller33b13562000-04-04 14:38:59 +10001950{
1951 Channel *c;
Ben Lindstrom4fed2be2002-06-25 23:17:36 +00001952 int id;
1953 u_int adjust;
Damien Miller33b13562000-04-04 14:38:59 +10001954
1955 if (!compat20)
1956 return;
1957
1958 /* Get the channel number and verify it. */
1959 id = packet_get_int();
1960 c = channel_lookup(id);
1961
1962 if (c == NULL || c->type != SSH_CHANNEL_OPEN) {
1963 log("Received window adjust for "
1964 "non-open channel %d.", id);
1965 return;
1966 }
1967 adjust = packet_get_int();
Damien Miller48b03fc2002-01-22 23:11:40 +11001968 packet_check_eom();
Ben Lindstrom4fed2be2002-06-25 23:17:36 +00001969 debug2("channel %d: rcvd adjust %u", id, adjust);
Damien Miller33b13562000-04-04 14:38:59 +10001970 c->remote_window += adjust;
1971}
1972
Damien Miller4af51302000-04-16 11:18:38 +10001973void
Damien Miller630d6f42002-01-22 23:17:30 +11001974channel_input_port_open(int type, u_int32_t seq, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001975{
Ben Lindstrome9c99912001-06-09 00:41:05 +00001976 Channel *c = NULL;
1977 u_short host_port;
1978 char *host, *originator_string;
1979 int remote_id, sock = -1;
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001980
Ben Lindstrome9c99912001-06-09 00:41:05 +00001981 remote_id = packet_get_int();
1982 host = packet_get_string(NULL);
1983 host_port = packet_get_int();
1984
1985 if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
1986 originator_string = packet_get_string(NULL);
1987 } else {
1988 originator_string = xstrdup("unknown (remote did not supply name)");
1989 }
Damien Miller48b03fc2002-01-22 23:11:40 +11001990 packet_check_eom();
Ben Lindstrome9c99912001-06-09 00:41:05 +00001991 sock = channel_connect_to(host, host_port);
1992 if (sock != -1) {
1993 c = channel_new("connected socket",
1994 SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0,
1995 originator_string, 1);
Damien Miller699d0032002-02-08 22:07:16 +11001996 c->remote_id = remote_id;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001997 }
Ben Lindstrome9c99912001-06-09 00:41:05 +00001998 if (c == NULL) {
1999 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2000 packet_put_int(remote_id);
2001 packet_send();
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002002 }
Ben Lindstrome9c99912001-06-09 00:41:05 +00002003 xfree(host);
Ben Lindstrom5744dc42001-04-13 23:28:01 +00002004}
2005
2006
Ben Lindstrome9c99912001-06-09 00:41:05 +00002007/* -- tcp forwarding */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002008
Ben Lindstrom908afed2001-10-03 17:34:59 +00002009void
2010channel_set_af(int af)
2011{
2012 IPv4or6 = af;
2013}
2014
Damien Millerb16461c2002-01-22 23:29:22 +11002015static int
2016channel_setup_fwd_listener(int type, const char *listen_addr, u_short listen_port,
2017 const char *host_to_connect, u_short port_to_connect, int gateway_ports)
Damien Miller0bc1bd82000-11-13 22:57:25 +11002018{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002019 Channel *c;
Damien Millerb16461c2002-01-22 23:29:22 +11002020 int success, sock, on = 1;
Damien Miller34132e52000-01-14 15:45:46 +11002021 struct addrinfo hints, *ai, *aitop;
Damien Miller0bc1bd82000-11-13 22:57:25 +11002022 const char *host;
Damien Millerb16461c2002-01-22 23:29:22 +11002023 char ntop[NI_MAXHOST], strport[NI_MAXSERV];
Damien Miller5428f641999-11-25 11:54:57 +11002024 struct linger linger;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002025
Kevin Steves12057502001-02-05 14:54:34 +00002026 success = 0;
Damien Millerb16461c2002-01-22 23:29:22 +11002027 host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
2028 listen_addr : host_to_connect;
Kevin Steves12057502001-02-05 14:54:34 +00002029
Damien Millerb16461c2002-01-22 23:29:22 +11002030 if (host == NULL) {
2031 error("No forward host name.");
2032 return success;
Damien Miller0bc1bd82000-11-13 22:57:25 +11002033 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002034 if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) {
Kevin Steves12057502001-02-05 14:54:34 +00002035 error("Forward host name too long.");
2036 return success;
2037 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002038
Damien Miller5428f641999-11-25 11:54:57 +11002039 /*
Damien Miller34132e52000-01-14 15:45:46 +11002040 * getaddrinfo returns a loopback address if the hostname is
2041 * set to NULL and hints.ai_flags is not AI_PASSIVE
Damien Miller5428f641999-11-25 11:54:57 +11002042 */
Damien Miller34132e52000-01-14 15:45:46 +11002043 memset(&hints, 0, sizeof(hints));
2044 hints.ai_family = IPv4or6;
2045 hints.ai_flags = gateway_ports ? AI_PASSIVE : 0;
2046 hints.ai_socktype = SOCK_STREAM;
Damien Miller0bc1bd82000-11-13 22:57:25 +11002047 snprintf(strport, sizeof strport, "%d", listen_port);
Damien Miller34132e52000-01-14 15:45:46 +11002048 if (getaddrinfo(NULL, strport, &hints, &aitop) != 0)
2049 packet_disconnect("getaddrinfo: fatal error");
Damien Miller5428f641999-11-25 11:54:57 +11002050
Damien Miller34132e52000-01-14 15:45:46 +11002051 for (ai = aitop; ai; ai = ai->ai_next) {
2052 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2053 continue;
2054 if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2055 strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
Damien Millerb16461c2002-01-22 23:29:22 +11002056 error("channel_setup_fwd_listener: getnameinfo failed");
Damien Miller34132e52000-01-14 15:45:46 +11002057 continue;
2058 }
2059 /* Create a port to listen for the host. */
2060 sock = socket(ai->ai_family, SOCK_STREAM, 0);
2061 if (sock < 0) {
2062 /* this is no error since kernel may not support ipv6 */
2063 verbose("socket: %.100s", strerror(errno));
2064 continue;
2065 }
2066 /*
2067 * Set socket options. We would like the socket to disappear
2068 * as soon as it has been closed for whatever reason.
2069 */
Ben Lindstrom733a2352002-03-05 01:31:28 +00002070 setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
Damien Miller34132e52000-01-14 15:45:46 +11002071 linger.l_onoff = 1;
2072 linger.l_linger = 5;
Ben Lindstrom733a2352002-03-05 01:31:28 +00002073 setsockopt(sock, SOL_SOCKET, SO_LINGER, &linger, sizeof(linger));
Damien Miller34132e52000-01-14 15:45:46 +11002074 debug("Local forwarding listening on %s port %s.", ntop, strport);
Damien Miller95def091999-11-25 00:26:21 +11002075
Damien Miller34132e52000-01-14 15:45:46 +11002076 /* Bind the socket to the address. */
2077 if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2078 /* address can be in use ipv6 address is already bound */
Damien Miller3c7eeb22000-03-03 22:35:33 +11002079 if (!ai->ai_next)
2080 error("bind: %.100s", strerror(errno));
2081 else
2082 verbose("bind: %.100s", strerror(errno));
Kevin Stevesef4eea92001-02-05 12:42:17 +00002083
Damien Miller34132e52000-01-14 15:45:46 +11002084 close(sock);
2085 continue;
2086 }
2087 /* Start listening for connections on the socket. */
2088 if (listen(sock, 5) < 0) {
2089 error("listen: %.100s", strerror(errno));
2090 close(sock);
2091 continue;
2092 }
2093 /* Allocate a channel number for the socket. */
Ben Lindstrome9c99912001-06-09 00:41:05 +00002094 c = channel_new("port listener", type, sock, sock, -1,
Damien Millerbd483e72000-04-30 10:00:53 +10002095 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
Damien Miller69b69aa2000-10-28 14:19:58 +11002096 0, xstrdup("port listener"), 1);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002097 strlcpy(c->path, host, sizeof(c->path));
2098 c->host_port = port_to_connect;
2099 c->listening_port = listen_port;
Damien Miller34132e52000-01-14 15:45:46 +11002100 success = 1;
2101 }
2102 if (success == 0)
Damien Millerb16461c2002-01-22 23:29:22 +11002103 error("channel_setup_fwd_listener: cannot listen to port: %d",
Kevin Steves12057502001-02-05 14:54:34 +00002104 listen_port);
Damien Miller34132e52000-01-14 15:45:46 +11002105 freeaddrinfo(aitop);
Kevin Steves12057502001-02-05 14:54:34 +00002106 return success;
Damien Miller95def091999-11-25 00:26:21 +11002107}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002108
Damien Millerb16461c2002-01-22 23:29:22 +11002109/* protocol local port fwd, used by ssh (and sshd in v1) */
2110int
2111channel_setup_local_fwd_listener(u_short listen_port,
2112 const char *host_to_connect, u_short port_to_connect, int gateway_ports)
2113{
2114 return channel_setup_fwd_listener(SSH_CHANNEL_PORT_LISTENER,
2115 NULL, listen_port, host_to_connect, port_to_connect, gateway_ports);
2116}
2117
2118/* protocol v2 remote port fwd, used by sshd */
2119int
2120channel_setup_remote_fwd_listener(const char *listen_address,
2121 u_short listen_port, int gateway_ports)
2122{
2123 return channel_setup_fwd_listener(SSH_CHANNEL_RPORT_LISTENER,
2124 listen_address, listen_port, NULL, 0, gateway_ports);
2125}
2126
Damien Miller5428f641999-11-25 11:54:57 +11002127/*
2128 * Initiate forwarding of connections to port "port" on remote host through
2129 * the secure channel to host:port from local side.
2130 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002131
Damien Miller4af51302000-04-16 11:18:38 +10002132void
Damien Miller0bc1bd82000-11-13 22:57:25 +11002133channel_request_remote_forwarding(u_short listen_port,
2134 const char *host_to_connect, u_short port_to_connect)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002135{
Damien Millerdff50992002-01-22 23:16:32 +11002136 int type, success = 0;
Damien Miller0bc1bd82000-11-13 22:57:25 +11002137
Damien Miller95def091999-11-25 00:26:21 +11002138 /* Record locally that connection to this host/port is permitted. */
2139 if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2140 fatal("channel_request_remote_forwarding: too many forwards");
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002141
Damien Miller95def091999-11-25 00:26:21 +11002142 /* Send the forward request to the remote side. */
Damien Miller33b13562000-04-04 14:38:59 +10002143 if (compat20) {
2144 const char *address_to_bind = "0.0.0.0";
2145 packet_start(SSH2_MSG_GLOBAL_REQUEST);
2146 packet_put_cstring("tcpip-forward");
Damien Miller2797f7f2002-04-23 21:09:44 +10002147 packet_put_char(1); /* boolean: want reply */
Damien Miller33b13562000-04-04 14:38:59 +10002148 packet_put_cstring(address_to_bind);
2149 packet_put_int(listen_port);
Damien Miller0bc1bd82000-11-13 22:57:25 +11002150 packet_send();
2151 packet_write_wait();
2152 /* Assume that server accepts the request */
2153 success = 1;
Damien Miller33b13562000-04-04 14:38:59 +10002154 } else {
2155 packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
Damien Miller33b13562000-04-04 14:38:59 +10002156 packet_put_int(listen_port);
Damien Miller8bb73be2000-04-19 16:26:12 +10002157 packet_put_cstring(host_to_connect);
2158 packet_put_int(port_to_connect);
Damien Miller33b13562000-04-04 14:38:59 +10002159 packet_send();
2160 packet_write_wait();
Damien Miller0bc1bd82000-11-13 22:57:25 +11002161
2162 /* Wait for response from the remote side. */
Damien Millerdff50992002-01-22 23:16:32 +11002163 type = packet_read();
Damien Miller0bc1bd82000-11-13 22:57:25 +11002164 switch (type) {
2165 case SSH_SMSG_SUCCESS:
2166 success = 1;
2167 break;
2168 case SSH_SMSG_FAILURE:
2169 log("Warning: Server denied remote port forwarding.");
2170 break;
2171 default:
2172 /* Unknown packet */
2173 packet_disconnect("Protocol error for port forward request:"
2174 "received packet type %d.", type);
2175 }
2176 }
2177 if (success) {
2178 permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
2179 permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
2180 permitted_opens[num_permitted_opens].listen_port = listen_port;
2181 num_permitted_opens++;
Damien Miller33b13562000-04-04 14:38:59 +10002182 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002183}
2184
Damien Miller5428f641999-11-25 11:54:57 +11002185/*
2186 * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
2187 * listening for the port, and sends back a success reply (or disconnect
2188 * message if there was an error). This never returns if there was an error.
2189 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002190
Damien Miller4af51302000-04-16 11:18:38 +10002191void
Damien Millere247cc42000-05-07 12:03:14 +10002192channel_input_port_forward_request(int is_root, int gateway_ports)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002193{
Damien Milleraae6c611999-12-06 11:47:28 +11002194 u_short port, host_port;
Damien Miller95def091999-11-25 00:26:21 +11002195 char *hostname;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002196
Damien Miller95def091999-11-25 00:26:21 +11002197 /* Get arguments from the packet. */
2198 port = packet_get_int();
2199 hostname = packet_get_string(NULL);
2200 host_port = packet_get_int();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002201
Damien Millerbac2d8a2000-09-05 16:13:06 +11002202#ifndef HAVE_CYGWIN
Damien Miller5428f641999-11-25 11:54:57 +11002203 /*
2204 * Check that an unprivileged user is not trying to forward a
2205 * privileged port.
2206 */
Damien Miller95def091999-11-25 00:26:21 +11002207 if (port < IPPORT_RESERVED && !is_root)
2208 packet_disconnect("Requested forwarding of port %d but user is not root.",
2209 port);
Damien Millerbac2d8a2000-09-05 16:13:06 +11002210#endif
Damien Miller0bc1bd82000-11-13 22:57:25 +11002211 /* Initiate forwarding */
Damien Millerb16461c2002-01-22 23:29:22 +11002212 channel_setup_local_fwd_listener(port, hostname, host_port, gateway_ports);
Damien Miller95def091999-11-25 00:26:21 +11002213
2214 /* Free the argument string. */
2215 xfree(hostname);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002216}
2217
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002218/*
2219 * Permits opening to any host/port if permitted_opens[] is empty. This is
2220 * usually called by the server, because the user could connect to any port
2221 * anyway, and the server has no way to know but to trust the client anyway.
2222 */
2223void
Ben Lindstrom3c36bb22001-12-06 17:55:26 +00002224channel_permit_all_opens(void)
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002225{
2226 if (num_permitted_opens == 0)
2227 all_opens_permitted = 1;
2228}
2229
Ben Lindstroma3700052001-04-05 23:26:32 +00002230void
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002231channel_add_permitted_opens(char *host, int port)
2232{
2233 if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2234 fatal("channel_request_remote_forwarding: too many forwards");
2235 debug("allow port forwarding to host %s port %d", host, port);
2236
2237 permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
2238 permitted_opens[num_permitted_opens].port_to_connect = port;
2239 num_permitted_opens++;
2240
2241 all_opens_permitted = 0;
2242}
2243
Ben Lindstroma3700052001-04-05 23:26:32 +00002244void
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002245channel_clear_permitted_opens(void)
2246{
2247 int i;
2248
2249 for (i = 0; i < num_permitted_opens; i++)
2250 xfree(permitted_opens[i].host_to_connect);
2251 num_permitted_opens = 0;
2252
2253}
2254
2255
2256/* return socket to remote host, port */
Ben Lindstrombba81212001-06-25 05:01:22 +00002257static int
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002258connect_to(const char *host, u_short port)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002259{
Damien Miller34132e52000-01-14 15:45:46 +11002260 struct addrinfo hints, *ai, *aitop;
2261 char ntop[NI_MAXHOST], strport[NI_MAXSERV];
2262 int gaierr;
Damien Millerb38eff82000-04-01 11:09:21 +10002263 int sock = -1;
Damien Miller95def091999-11-25 00:26:21 +11002264
Damien Miller34132e52000-01-14 15:45:46 +11002265 memset(&hints, 0, sizeof(hints));
2266 hints.ai_family = IPv4or6;
2267 hints.ai_socktype = SOCK_STREAM;
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002268 snprintf(strport, sizeof strport, "%d", port);
Damien Miller34132e52000-01-14 15:45:46 +11002269 if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) {
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002270 error("connect_to %.100s: unknown host (%s)", host,
2271 gai_strerror(gaierr));
Damien Millerb38eff82000-04-01 11:09:21 +10002272 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002273 }
Damien Miller34132e52000-01-14 15:45:46 +11002274 for (ai = aitop; ai; ai = ai->ai_next) {
2275 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2276 continue;
2277 if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2278 strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002279 error("connect_to: getnameinfo failed");
Damien Miller34132e52000-01-14 15:45:46 +11002280 continue;
2281 }
Damien Miller34132e52000-01-14 15:45:46 +11002282 sock = socket(ai->ai_family, SOCK_STREAM, 0);
2283 if (sock < 0) {
2284 error("socket: %.100s", strerror(errno));
2285 continue;
2286 }
Ben Lindstrom48bd7c12001-01-09 00:35:42 +00002287 if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0)
Ben Lindstrom7ad97102000-12-06 01:42:49 +00002288 fatal("connect_to: F_SETFL: %s", strerror(errno));
Ben Lindstrom7ad97102000-12-06 01:42:49 +00002289 if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 &&
2290 errno != EINPROGRESS) {
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002291 error("connect_to %.100s port %s: %.100s", ntop, strport,
Damien Miller34132e52000-01-14 15:45:46 +11002292 strerror(errno));
2293 close(sock);
Kevin Stevesef4eea92001-02-05 12:42:17 +00002294 continue; /* fail -- try next */
Damien Miller34132e52000-01-14 15:45:46 +11002295 }
2296 break; /* success */
2297
2298 }
2299 freeaddrinfo(aitop);
Damien Miller34132e52000-01-14 15:45:46 +11002300 if (!ai) {
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002301 error("connect_to %.100s port %d: failed.", host, port);
Damien Millerb38eff82000-04-01 11:09:21 +10002302 return -1;
2303 }
2304 /* success */
Ben Lindstrom1ebd7a52002-02-26 18:12:51 +00002305 set_nodelay(sock);
Damien Millerb38eff82000-04-01 11:09:21 +10002306 return sock;
2307}
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002308
Damien Miller0bc1bd82000-11-13 22:57:25 +11002309int
Ben Lindstrom173e6462001-07-04 05:15:15 +00002310channel_connect_by_listen_address(u_short listen_port)
Damien Miller0bc1bd82000-11-13 22:57:25 +11002311{
2312 int i;
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002313
Damien Miller0bc1bd82000-11-13 22:57:25 +11002314 for (i = 0; i < num_permitted_opens; i++)
2315 if (permitted_opens[i].listen_port == listen_port)
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002316 return connect_to(
Damien Miller0bc1bd82000-11-13 22:57:25 +11002317 permitted_opens[i].host_to_connect,
2318 permitted_opens[i].port_to_connect);
Ben Lindstromc72745a2000-12-02 19:03:54 +00002319 error("WARNING: Server requests forwarding for unknown listen_port %d",
2320 listen_port);
Damien Miller0bc1bd82000-11-13 22:57:25 +11002321 return -1;
2322}
Damien Millerb38eff82000-04-01 11:09:21 +10002323
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002324/* Check if connecting to that port is permitted and connect. */
2325int
2326channel_connect_to(const char *host, u_short port)
2327{
2328 int i, permit;
2329
2330 permit = all_opens_permitted;
2331 if (!permit) {
2332 for (i = 0; i < num_permitted_opens; i++)
2333 if (permitted_opens[i].port_to_connect == port &&
2334 strcmp(permitted_opens[i].host_to_connect, host) == 0)
2335 permit = 1;
2336
2337 }
2338 if (!permit) {
2339 log("Received request to connect to host %.100s port %d, "
2340 "but the request was denied.", host, port);
2341 return -1;
2342 }
2343 return connect_to(host, port);
2344}
2345
Ben Lindstrome9c99912001-06-09 00:41:05 +00002346/* -- X11 forwarding */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002347
Damien Miller5428f641999-11-25 11:54:57 +11002348/*
2349 * Creates an internet domain socket for listening for X11 connections.
Ben Lindstroma9d2c892002-06-23 21:48:28 +00002350 * Returns 0 and a suitable display number for the DISPLAY variable
2351 * stored in display_numberp , or -1 if an error occurs.
Damien Miller5428f641999-11-25 11:54:57 +11002352 */
Kevin Steves366298c2001-12-19 17:58:01 +00002353int
Damien Miller95c249f2002-02-05 12:11:34 +11002354x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
Ben Lindstroma9d2c892002-06-23 21:48:28 +00002355 int single_connection, u_int *display_numberp)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002356{
Damien Millere7378562001-12-21 14:58:35 +11002357 Channel *nc = NULL;
Damien Milleraae6c611999-12-06 11:47:28 +11002358 int display_number, sock;
2359 u_short port;
Damien Miller34132e52000-01-14 15:45:46 +11002360 struct addrinfo hints, *ai, *aitop;
2361 char strport[NI_MAXSERV];
2362 int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002363
Damien Millera34a28b1999-12-14 10:47:15 +11002364 for (display_number = x11_display_offset;
Damien Miller9f0f5c62001-12-21 14:45:46 +11002365 display_number < MAX_DISPLAYS;
2366 display_number++) {
Damien Miller95def091999-11-25 00:26:21 +11002367 port = 6000 + display_number;
Damien Miller34132e52000-01-14 15:45:46 +11002368 memset(&hints, 0, sizeof(hints));
2369 hints.ai_family = IPv4or6;
Damien Miller95c249f2002-02-05 12:11:34 +11002370 hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
Damien Miller34132e52000-01-14 15:45:46 +11002371 hints.ai_socktype = SOCK_STREAM;
2372 snprintf(strport, sizeof strport, "%d", port);
2373 if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
2374 error("getaddrinfo: %.100s", gai_strerror(gaierr));
Kevin Steves366298c2001-12-19 17:58:01 +00002375 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002376 }
Damien Miller34132e52000-01-14 15:45:46 +11002377 for (ai = aitop; ai; ai = ai->ai_next) {
2378 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2379 continue;
2380 sock = socket(ai->ai_family, SOCK_STREAM, 0);
2381 if (sock < 0) {
Damien Miller89d97962000-10-14 12:37:19 +11002382 if ((errno != EINVAL) && (errno != EAFNOSUPPORT)) {
Damien Millere2192732000-01-17 13:22:55 +11002383 error("socket: %.100s", strerror(errno));
Kevin Steves366298c2001-12-19 17:58:01 +00002384 return -1;
Damien Millere2192732000-01-17 13:22:55 +11002385 } else {
Damien Millercb5e44a2000-09-29 12:12:36 +11002386 debug("x11_create_display_inet: Socket family %d not supported",
2387 ai->ai_family);
Damien Millere2192732000-01-17 13:22:55 +11002388 continue;
2389 }
Damien Miller34132e52000-01-14 15:45:46 +11002390 }
Kevin Stevesdf75dd22002-06-04 20:52:19 +00002391#ifdef IPV6_V6ONLY
2392 if (ai->ai_family == AF_INET6) {
2393 int on = 1;
2394 if (setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) < 0)
2395 error("setsockopt IPV6_V6ONLY: %.100s", strerror(errno));
2396 }
2397#endif
Damien Miller34132e52000-01-14 15:45:46 +11002398 if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2399 debug("bind port %d: %.100s", port, strerror(errno));
Damien Miller34132e52000-01-14 15:45:46 +11002400 close(sock);
Damien Miller3c7eeb22000-03-03 22:35:33 +11002401
2402 if (ai->ai_next)
2403 continue;
2404
Damien Miller34132e52000-01-14 15:45:46 +11002405 for (n = 0; n < num_socks; n++) {
Damien Miller34132e52000-01-14 15:45:46 +11002406 close(socks[n]);
2407 }
2408 num_socks = 0;
2409 break;
2410 }
2411 socks[num_socks++] = sock;
Damien Miller7bcb0892000-03-11 20:45:40 +11002412#ifndef DONT_TRY_OTHER_AF
Damien Miller34132e52000-01-14 15:45:46 +11002413 if (num_socks == NUM_SOCKS)
2414 break;
Damien Miller7bcb0892000-03-11 20:45:40 +11002415#else
Kevin Stevesdf75dd22002-06-04 20:52:19 +00002416 if (x11_use_localhost) {
2417 if (num_socks == NUM_SOCKS)
2418 break;
2419 } else {
2420 break;
2421 }
Damien Miller7bcb0892000-03-11 20:45:40 +11002422#endif
Damien Miller95def091999-11-25 00:26:21 +11002423 }
Ben Lindstrom87b147f2001-01-25 00:41:12 +00002424 freeaddrinfo(aitop);
Damien Miller34132e52000-01-14 15:45:46 +11002425 if (num_socks > 0)
2426 break;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002427 }
Damien Miller95def091999-11-25 00:26:21 +11002428 if (display_number >= MAX_DISPLAYS) {
2429 error("Failed to allocate internet-domain X11 display socket.");
Kevin Steves366298c2001-12-19 17:58:01 +00002430 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002431 }
Damien Miller95def091999-11-25 00:26:21 +11002432 /* Start listening for connections on the socket. */
Damien Miller34132e52000-01-14 15:45:46 +11002433 for (n = 0; n < num_socks; n++) {
2434 sock = socks[n];
2435 if (listen(sock, 5) < 0) {
2436 error("listen: %.100s", strerror(errno));
Damien Miller34132e52000-01-14 15:45:46 +11002437 close(sock);
Kevin Steves366298c2001-12-19 17:58:01 +00002438 return -1;
Damien Miller34132e52000-01-14 15:45:46 +11002439 }
Damien Miller95def091999-11-25 00:26:21 +11002440 }
Damien Miller34132e52000-01-14 15:45:46 +11002441
Damien Miller34132e52000-01-14 15:45:46 +11002442 /* Allocate a channel for each socket. */
2443 for (n = 0; n < num_socks; n++) {
2444 sock = socks[n];
Damien Millere7378562001-12-21 14:58:35 +11002445 nc = channel_new("x11 listener",
Damien Millerbd483e72000-04-30 10:00:53 +10002446 SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
2447 CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
Damien Miller69b69aa2000-10-28 14:19:58 +11002448 0, xstrdup("X11 inet listener"), 1);
Damien Miller699d0032002-02-08 22:07:16 +11002449 nc->single_connection = single_connection;
Damien Miller34132e52000-01-14 15:45:46 +11002450 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002451
Kevin Steves366298c2001-12-19 17:58:01 +00002452 /* Return the display number for the DISPLAY environment variable. */
Ben Lindstroma9d2c892002-06-23 21:48:28 +00002453 *display_numberp = display_number;
2454 return (0);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002455}
2456
Ben Lindstrombba81212001-06-25 05:01:22 +00002457static int
Ben Lindstrom46c16222000-12-22 01:43:59 +00002458connect_local_xsocket(u_int dnr)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002459{
Damien Miller95def091999-11-25 00:26:21 +11002460 int sock;
2461 struct sockaddr_un addr;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002462
Damien Miller3afe3752001-12-21 12:39:51 +11002463 sock = socket(AF_UNIX, SOCK_STREAM, 0);
2464 if (sock < 0)
2465 error("socket: %.100s", strerror(errno));
2466 memset(&addr, 0, sizeof(addr));
2467 addr.sun_family = AF_UNIX;
2468 snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
2469 if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0)
2470 return sock;
2471 close(sock);
Damien Miller95def091999-11-25 00:26:21 +11002472 error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
2473 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002474}
2475
Damien Millerbd483e72000-04-30 10:00:53 +10002476int
2477x11_connect_display(void)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002478{
Damien Miller398e1cf2002-02-05 11:52:13 +11002479 int display_number, sock = 0;
Damien Miller95def091999-11-25 00:26:21 +11002480 const char *display;
Damien Millerbd483e72000-04-30 10:00:53 +10002481 char buf[1024], *cp;
Damien Miller34132e52000-01-14 15:45:46 +11002482 struct addrinfo hints, *ai, *aitop;
2483 char strport[NI_MAXSERV];
2484 int gaierr;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002485
Damien Miller95def091999-11-25 00:26:21 +11002486 /* Try to open a socket for the local X server. */
2487 display = getenv("DISPLAY");
2488 if (!display) {
2489 error("DISPLAY not set.");
Damien Millerbd483e72000-04-30 10:00:53 +10002490 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002491 }
Damien Miller5428f641999-11-25 11:54:57 +11002492 /*
2493 * Now we decode the value of the DISPLAY variable and make a
2494 * connection to the real X server.
2495 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002496
Damien Miller5428f641999-11-25 11:54:57 +11002497 /*
2498 * Check if it is a unix domain socket. Unix domain displays are in
2499 * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
2500 */
Damien Miller95def091999-11-25 00:26:21 +11002501 if (strncmp(display, "unix:", 5) == 0 ||
2502 display[0] == ':') {
2503 /* Connect to the unix domain socket. */
2504 if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) {
2505 error("Could not parse display number from DISPLAY: %.100s",
Damien Miller9f0f5c62001-12-21 14:45:46 +11002506 display);
Damien Millerbd483e72000-04-30 10:00:53 +10002507 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002508 }
2509 /* Create a socket. */
2510 sock = connect_local_xsocket(display_number);
2511 if (sock < 0)
Damien Millerbd483e72000-04-30 10:00:53 +10002512 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002513
2514 /* OK, we now have a connection to the display. */
Damien Millerbd483e72000-04-30 10:00:53 +10002515 return sock;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002516 }
Damien Miller5428f641999-11-25 11:54:57 +11002517 /*
2518 * Connect to an inet socket. The DISPLAY value is supposedly
2519 * hostname:d[.s], where hostname may also be numeric IP address.
2520 */
Ben Lindstromccd8d072001-12-07 17:26:48 +00002521 strlcpy(buf, display, sizeof(buf));
Damien Miller95def091999-11-25 00:26:21 +11002522 cp = strchr(buf, ':');
2523 if (!cp) {
2524 error("Could not find ':' in DISPLAY: %.100s", display);
Damien Millerbd483e72000-04-30 10:00:53 +10002525 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002526 }
Damien Miller95def091999-11-25 00:26:21 +11002527 *cp = 0;
Damien Miller5428f641999-11-25 11:54:57 +11002528 /* buf now contains the host name. But first we parse the display number. */
Damien Miller95def091999-11-25 00:26:21 +11002529 if (sscanf(cp + 1, "%d", &display_number) != 1) {
2530 error("Could not parse display number from DISPLAY: %.100s",
Damien Miller9f0f5c62001-12-21 14:45:46 +11002531 display);
Damien Millerbd483e72000-04-30 10:00:53 +10002532 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002533 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002534
Damien Miller34132e52000-01-14 15:45:46 +11002535 /* Look up the host address */
2536 memset(&hints, 0, sizeof(hints));
2537 hints.ai_family = IPv4or6;
2538 hints.ai_socktype = SOCK_STREAM;
2539 snprintf(strport, sizeof strport, "%d", 6000 + display_number);
2540 if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
2541 error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr));
Damien Millerbd483e72000-04-30 10:00:53 +10002542 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002543 }
Damien Miller34132e52000-01-14 15:45:46 +11002544 for (ai = aitop; ai; ai = ai->ai_next) {
2545 /* Create a socket. */
2546 sock = socket(ai->ai_family, SOCK_STREAM, 0);
2547 if (sock < 0) {
2548 debug("socket: %.100s", strerror(errno));
Damien Millerb38eff82000-04-01 11:09:21 +10002549 continue;
2550 }
2551 /* Connect it to the display. */
2552 if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2553 debug("connect %.100s port %d: %.100s", buf,
2554 6000 + display_number, strerror(errno));
2555 close(sock);
2556 continue;
2557 }
2558 /* Success */
2559 break;
Damien Miller34132e52000-01-14 15:45:46 +11002560 }
Damien Miller34132e52000-01-14 15:45:46 +11002561 freeaddrinfo(aitop);
2562 if (!ai) {
Damien Miller4af51302000-04-16 11:18:38 +10002563 error("connect %.100s port %d: %.100s", buf, 6000 + display_number,
Damien Miller34132e52000-01-14 15:45:46 +11002564 strerror(errno));
Damien Millerbd483e72000-04-30 10:00:53 +10002565 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002566 }
Damien Miller398e1cf2002-02-05 11:52:13 +11002567 set_nodelay(sock);
Damien Millerbd483e72000-04-30 10:00:53 +10002568 return sock;
2569}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002570
Damien Millerbd483e72000-04-30 10:00:53 +10002571/*
2572 * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
2573 * the remote channel number. We should do whatever we want, and respond
2574 * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
2575 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002576
Damien Millerbd483e72000-04-30 10:00:53 +10002577void
Damien Miller630d6f42002-01-22 23:17:30 +11002578x11_input_open(int type, u_int32_t seq, void *ctxt)
Damien Millerbd483e72000-04-30 10:00:53 +10002579{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002580 Channel *c = NULL;
2581 int remote_id, sock = 0;
Damien Millerbd483e72000-04-30 10:00:53 +10002582 char *remote_host;
Damien Millerbd483e72000-04-30 10:00:53 +10002583
2584 debug("Received X11 open request.");
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002585
2586 remote_id = packet_get_int();
Ben Lindstrome9c99912001-06-09 00:41:05 +00002587
2588 if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002589 remote_host = packet_get_string(NULL);
2590 } else {
2591 remote_host = xstrdup("unknown (remote did not supply name)");
2592 }
Damien Miller48b03fc2002-01-22 23:11:40 +11002593 packet_check_eom();
Damien Millerbd483e72000-04-30 10:00:53 +10002594
2595 /* Obtain a connection to the real X display. */
2596 sock = x11_connect_display();
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002597 if (sock != -1) {
2598 /* Allocate a channel for this connection. */
2599 c = channel_new("connected x11 socket",
2600 SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
2601 remote_host, 1);
Damien Miller699d0032002-02-08 22:07:16 +11002602 c->remote_id = remote_id;
2603 c->force_drain = 1;
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002604 }
2605 if (c == NULL) {
Damien Millerbd483e72000-04-30 10:00:53 +10002606 /* Send refusal to the remote host. */
2607 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002608 packet_put_int(remote_id);
Damien Millerbd483e72000-04-30 10:00:53 +10002609 } else {
Damien Millerbd483e72000-04-30 10:00:53 +10002610 /* Send a confirmation to the remote host. */
2611 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002612 packet_put_int(remote_id);
2613 packet_put_int(c->self);
Damien Millerbd483e72000-04-30 10:00:53 +10002614 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002615 packet_send();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002616}
2617
Damien Miller69b69aa2000-10-28 14:19:58 +11002618/* dummy protocol handler that denies SSH-1 requests (agent/x11) */
2619void
Damien Miller630d6f42002-01-22 23:17:30 +11002620deny_input_open(int type, u_int32_t seq, void *ctxt)
Damien Miller69b69aa2000-10-28 14:19:58 +11002621{
2622 int rchan = packet_get_int();
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +00002623
Ben Lindstrom1c37c6a2001-12-06 18:00:18 +00002624 switch (type) {
Damien Miller69b69aa2000-10-28 14:19:58 +11002625 case SSH_SMSG_AGENT_OPEN:
2626 error("Warning: ssh server tried agent forwarding.");
2627 break;
2628 case SSH_SMSG_X11_OPEN:
2629 error("Warning: ssh server tried X11 forwarding.");
2630 break;
2631 default:
Damien Miller630d6f42002-01-22 23:17:30 +11002632 error("deny_input_open: type %d", type);
Damien Miller69b69aa2000-10-28 14:19:58 +11002633 break;
2634 }
2635 error("Warning: this is probably a break in attempt by a malicious server.");
2636 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2637 packet_put_int(rchan);
2638 packet_send();
2639}
2640
Damien Miller5428f641999-11-25 11:54:57 +11002641/*
2642 * Requests forwarding of X11 connections, generates fake authentication
2643 * data, and enables authentication spoofing.
Ben Lindstrome9c99912001-06-09 00:41:05 +00002644 * This should be called in the client only.
Damien Miller5428f641999-11-25 11:54:57 +11002645 */
Damien Miller4af51302000-04-16 11:18:38 +10002646void
Damien Millerbd483e72000-04-30 10:00:53 +10002647x11_request_forwarding_with_spoofing(int client_session_id,
2648 const char *proto, const char *data)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002649{
Ben Lindstrom46c16222000-12-22 01:43:59 +00002650 u_int data_len = (u_int) strlen(data) / 2;
Ben Lindstromb3211a82001-02-10 22:33:19 +00002651 u_int i, value, len;
Damien Miller95def091999-11-25 00:26:21 +11002652 char *new_data;
2653 int screen_number;
2654 const char *cp;
2655 u_int32_t rand = 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002656
Damien Miller95def091999-11-25 00:26:21 +11002657 cp = getenv("DISPLAY");
2658 if (cp)
2659 cp = strchr(cp, ':');
2660 if (cp)
2661 cp = strchr(cp, '.');
2662 if (cp)
2663 screen_number = atoi(cp + 1);
2664 else
2665 screen_number = 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002666
Damien Miller95def091999-11-25 00:26:21 +11002667 /* Save protocol name. */
2668 x11_saved_proto = xstrdup(proto);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002669
Damien Miller5428f641999-11-25 11:54:57 +11002670 /*
2671 * Extract real authentication data and generate fake data of the
2672 * same length.
2673 */
Damien Miller95def091999-11-25 00:26:21 +11002674 x11_saved_data = xmalloc(data_len);
2675 x11_fake_data = xmalloc(data_len);
2676 for (i = 0; i < data_len; i++) {
2677 if (sscanf(data + 2 * i, "%2x", &value) != 1)
2678 fatal("x11_request_forwarding: bad authentication data: %.100s", data);
2679 if (i % 4 == 0)
2680 rand = arc4random();
2681 x11_saved_data[i] = value;
2682 x11_fake_data[i] = rand & 0xff;
2683 rand >>= 8;
2684 }
2685 x11_saved_data_len = data_len;
2686 x11_fake_data_len = data_len;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002687
Damien Miller95def091999-11-25 00:26:21 +11002688 /* Convert the fake data into hex. */
Ben Lindstromb3211a82001-02-10 22:33:19 +00002689 len = 2 * data_len + 1;
2690 new_data = xmalloc(len);
Damien Miller95def091999-11-25 00:26:21 +11002691 for (i = 0; i < data_len; i++)
Ben Lindstromb3211a82001-02-10 22:33:19 +00002692 snprintf(new_data + 2 * i, len - 2 * i,
2693 "%02x", (u_char) x11_fake_data[i]);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002694
Damien Miller95def091999-11-25 00:26:21 +11002695 /* Send the request packet. */
Damien Millerbd483e72000-04-30 10:00:53 +10002696 if (compat20) {
2697 channel_request_start(client_session_id, "x11-req", 0);
2698 packet_put_char(0); /* XXX bool single connection */
2699 } else {
2700 packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
2701 }
2702 packet_put_cstring(proto);
2703 packet_put_cstring(new_data);
Damien Miller95def091999-11-25 00:26:21 +11002704 packet_put_int(screen_number);
2705 packet_send();
2706 packet_write_wait();
2707 xfree(new_data);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002708}
2709
Ben Lindstrome9c99912001-06-09 00:41:05 +00002710
2711/* -- agent forwarding */
2712
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002713/* Sends a message to the server to request authentication fd forwarding. */
2714
Damien Miller4af51302000-04-16 11:18:38 +10002715void
Ben Lindstrom3c36bb22001-12-06 17:55:26 +00002716auth_request_forwarding(void)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002717{
Damien Miller95def091999-11-25 00:26:21 +11002718 packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
2719 packet_send();
2720 packet_write_wait();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002721}
2722
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002723/* This is called to process an SSH_SMSG_AGENT_OPEN message. */
2724
Damien Miller4af51302000-04-16 11:18:38 +10002725void
Damien Miller630d6f42002-01-22 23:17:30 +11002726auth_input_open_request(int type, u_int32_t seq, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002727{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002728 Channel *c = NULL;
2729 int remote_id, sock;
Ben Lindstrome9c99912001-06-09 00:41:05 +00002730 char *name;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002731
Damien Miller95def091999-11-25 00:26:21 +11002732 /* Read the remote channel number from the message. */
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002733 remote_id = packet_get_int();
Damien Miller48b03fc2002-01-22 23:11:40 +11002734 packet_check_eom();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002735
Damien Miller5428f641999-11-25 11:54:57 +11002736 /*
2737 * Get a connection to the local authentication agent (this may again
2738 * get forwarded).
2739 */
Damien Miller95def091999-11-25 00:26:21 +11002740 sock = ssh_get_authentication_socket();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002741
Damien Miller5428f641999-11-25 11:54:57 +11002742 /*
2743 * If we could not connect the agent, send an error message back to
2744 * the server. This should never happen unless the agent dies,
2745 * because authentication forwarding is only enabled if we have an
2746 * agent.
2747 */
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002748 if (sock >= 0) {
Ben Lindstrome9c99912001-06-09 00:41:05 +00002749 name = xstrdup("authentication agent connection");
2750 c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
2751 -1, 0, 0, 0, name, 1);
Damien Miller699d0032002-02-08 22:07:16 +11002752 c->remote_id = remote_id;
2753 c->force_drain = 1;
Damien Miller95def091999-11-25 00:26:21 +11002754 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002755 if (c == NULL) {
2756 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2757 packet_put_int(remote_id);
2758 } else {
2759 /* Send a confirmation to the remote host. */
2760 debug("Forwarding authentication connection.");
2761 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
2762 packet_put_int(remote_id);
2763 packet_put_int(c->self);
2764 }
Damien Miller95def091999-11-25 00:26:21 +11002765 packet_send();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002766}