blob: 97c1fd31b948b51ba470585812bdc63a9832aed0 [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"
Damien Miller232711f2004-06-15 10:35:30 +100042RCSID("$OpenBSD: channels.c,v 1.205 2004/06/14 01:44:38 djm 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"
Darren Tucker46471c92003-07-03 13:55:19 +100057#include "bufaux.h"
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 Miller996acd22003-04-09 20:59:48 +1000145 logit("channel_lookup: %d: bad id", id);
Damien Millerb38eff82000-04-01 11:09:21 +1000146 return NULL;
147 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000148 c = channels[id];
149 if (c == NULL) {
Damien Miller996acd22003-04-09 20:59:48 +1000150 logit("channel_lookup: %d: bad id: channel free", id);
Damien Millerb38eff82000-04-01 11:09:21 +1000151 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;
Damien Miller0e220db2004-06-15 10:34:08 +1000175 c->ctl_fd = -1; /* XXX: set elsewhere */
Damien Miller6f83b8e2000-05-02 09:23:45 +1000176 c->efd = efd;
177 c->extended_usage = extusage;
Damien Miller69b69aa2000-10-28 14:19:58 +1100178
Damien Miller79438cc2001-02-16 12:34:57 +1100179 /* XXX ugly hack: nonblock is only set by the server */
180 if (nonblock && isatty(c->rfd)) {
Damien Millerfbdeece2003-09-02 22:52:31 +1000181 debug2("channel %d: rfd %d isatty", c->self, c->rfd);
Damien Miller79438cc2001-02-16 12:34:57 +1100182 c->isatty = 1;
183 if (!isatty(c->wfd)) {
Ben Lindstromcc74df72001-03-05 06:20:14 +0000184 error("channel %d: wfd %d is not a tty?",
Damien Miller79438cc2001-02-16 12:34:57 +1100185 c->self, c->wfd);
186 }
187 } else {
188 c->isatty = 0;
189 }
Ben Lindstrombeb5f332002-07-22 15:28:53 +0000190 c->wfd_isatty = isatty(c->wfd);
Damien Miller79438cc2001-02-16 12:34:57 +1100191
Damien Miller69b69aa2000-10-28 14:19:58 +1100192 /* enable nonblocking mode */
193 if (nonblock) {
194 if (rfd != -1)
195 set_nonblock(rfd);
196 if (wfd != -1)
197 set_nonblock(wfd);
198 if (efd != -1)
199 set_nonblock(efd);
200 }
Damien Miller6f83b8e2000-05-02 09:23:45 +1000201}
202
203/*
204 * Allocate a new channel object and set its type and socket. This will cause
205 * remote_name to be freed.
206 */
207
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000208Channel *
Damien Miller6f83b8e2000-05-02 09:23:45 +1000209channel_new(char *ctype, int type, int rfd, int wfd, int efd,
Ben Lindstrom4fed2be2002-06-25 23:17:36 +0000210 u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
Damien Miller6f83b8e2000-05-02 09:23:45 +1000211{
212 int i, found;
213 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000214
Damien Miller95def091999-11-25 00:26:21 +1100215 /* Do initial allocation if this is the first call. */
216 if (channels_alloc == 0) {
217 channels_alloc = 10;
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000218 channels = xmalloc(channels_alloc * sizeof(Channel *));
Damien Miller95def091999-11-25 00:26:21 +1100219 for (i = 0; i < channels_alloc; i++)
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000220 channels[i] = NULL;
Damien Miller95def091999-11-25 00:26:21 +1100221 }
222 /* Try to find a free slot where to put the new channel. */
223 for (found = -1, i = 0; i < channels_alloc; i++)
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000224 if (channels[i] == NULL) {
Damien Miller95def091999-11-25 00:26:21 +1100225 /* Found a free slot. */
226 found = i;
227 break;
228 }
229 if (found == -1) {
Damien Miller5428f641999-11-25 11:54:57 +1100230 /* There are no free slots. Take last+1 slot and expand the array. */
Damien Miller95def091999-11-25 00:26:21 +1100231 found = channels_alloc;
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 Miller5efcecc2003-09-17 07:31:14 +1000235 channels = xrealloc(channels,
236 (channels_alloc + 10) * sizeof(Channel *));
237 channels_alloc += 10;
Damien Millerd3444942000-09-30 14:20:03 +1100238 debug2("channel: expanding %d", channels_alloc);
Damien Miller95def091999-11-25 00:26:21 +1100239 for (i = found; i < channels_alloc; i++)
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000240 channels[i] = NULL;
Damien Miller95def091999-11-25 00:26:21 +1100241 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000242 /* Initialize and return new channel. */
243 c = channels[found] = xmalloc(sizeof(Channel));
Damien Miller4623a752001-10-10 15:03:58 +1000244 memset(c, 0, sizeof(Channel));
Damien Miller95def091999-11-25 00:26:21 +1100245 buffer_init(&c->input);
246 buffer_init(&c->output);
Damien Millerb38eff82000-04-01 11:09:21 +1000247 buffer_init(&c->extended);
Damien Miller5144df92002-01-22 23:28:45 +1100248 c->ostate = CHAN_OUTPUT_OPEN;
249 c->istate = CHAN_INPUT_OPEN;
250 c->flags = 0;
Damien Miller69b69aa2000-10-28 14:19:58 +1100251 channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
Damien Miller95def091999-11-25 00:26:21 +1100252 c->self = found;
253 c->type = type;
Damien Millerb38eff82000-04-01 11:09:21 +1000254 c->ctype = ctype;
Damien Millerbd483e72000-04-30 10:00:53 +1000255 c->local_window = window;
256 c->local_window_max = window;
257 c->local_consumed = 0;
258 c->local_maxpacket = maxpack;
Damien Miller95def091999-11-25 00:26:21 +1100259 c->remote_id = -1;
Damien Millerb1ca8bb2003-05-14 13:45:42 +1000260 c->remote_name = xstrdup(remote_name);
Damien Millerb38eff82000-04-01 11:09:21 +1000261 c->remote_window = 0;
262 c->remote_maxpacket = 0;
Ben Lindstrom944c4f02001-09-18 05:51:13 +0000263 c->force_drain = 0;
Damien Millere7378562001-12-21 14:58:35 +1100264 c->single_connection = 0;
Ben Lindstrom809744e2001-07-04 05:26:06 +0000265 c->detach_user = NULL;
Damien Miller67f0bc02002-02-05 12:23:08 +1100266 c->confirm = NULL;
Damien Miller0e220db2004-06-15 10:34:08 +1000267 c->confirm_ctx = NULL;
Damien Millerad833b32000-08-23 10:46:23 +1000268 c->input_filter = NULL;
Damien Miller95def091999-11-25 00:26:21 +1100269 debug("channel %d: new [%s]", found, remote_name);
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000270 return c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000271}
Damien Miller6f83b8e2000-05-02 09:23:45 +1000272
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000273static int
274channel_find_maxfd(void)
275{
276 int i, max = 0;
277 Channel *c;
278
279 for (i = 0; i < channels_alloc; i++) {
280 c = channels[i];
281 if (c != NULL) {
282 max = MAX(max, c->rfd);
283 max = MAX(max, c->wfd);
284 max = MAX(max, c->efd);
285 }
286 }
287 return max;
288}
289
290int
291channel_close_fd(int *fdp)
292{
293 int ret = 0, fd = *fdp;
294
295 if (fd != -1) {
296 ret = close(fd);
297 *fdp = -1;
298 if (fd == channel_max_fd)
299 channel_max_fd = channel_find_maxfd();
300 }
301 return ret;
302}
303
Damien Miller6f83b8e2000-05-02 09:23:45 +1000304/* Close all channel fd/socket. */
305
Ben Lindstrombba81212001-06-25 05:01:22 +0000306static void
Damien Miller6f83b8e2000-05-02 09:23:45 +1000307channel_close_fds(Channel *c)
308{
Damien Miller0e220db2004-06-15 10:34:08 +1000309 debug3("channel %d: close_fds r %d w %d e %d c %d",
310 c->self, c->rfd, c->wfd, c->efd, c->ctl_fd);
Ben Lindstromc0dee1a2001-06-05 20:52:50 +0000311
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000312 channel_close_fd(&c->sock);
Damien Miller0e220db2004-06-15 10:34:08 +1000313 channel_close_fd(&c->ctl_fd);
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000314 channel_close_fd(&c->rfd);
315 channel_close_fd(&c->wfd);
316 channel_close_fd(&c->efd);
Damien Miller6f83b8e2000-05-02 09:23:45 +1000317}
318
319/* Free the channel and close its fd/socket. */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000320
Damien Miller4af51302000-04-16 11:18:38 +1000321void
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000322channel_free(Channel *c)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000323{
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000324 char *s;
Ben Lindstromc0dee1a2001-06-05 20:52:50 +0000325 int i, n;
326
327 for (n = 0, i = 0; i < channels_alloc; i++)
328 if (channels[i])
329 n++;
Damien Millerfbdeece2003-09-02 22:52:31 +1000330 debug("channel %d: free: %s, nchannels %d", c->self,
Ben Lindstromc0dee1a2001-06-05 20:52:50 +0000331 c->remote_name ? c->remote_name : "???", n);
Ben Lindstrom6c3ae2b2000-12-30 03:25:14 +0000332
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000333 s = channel_open_message();
Damien Millerfbdeece2003-09-02 22:52:31 +1000334 debug3("channel %d: status: %s", c->self, s);
Ben Lindstrom6c3ae2b2000-12-30 03:25:14 +0000335 xfree(s);
336
Damien Miller6f83b8e2000-05-02 09:23:45 +1000337 if (c->sock != -1)
Damien Millerb38eff82000-04-01 11:09:21 +1000338 shutdown(c->sock, SHUT_RDWR);
Damien Miller0e220db2004-06-15 10:34:08 +1000339 if (c->ctl_fd != -1)
340 shutdown(c->ctl_fd, SHUT_RDWR);
Damien Miller6f83b8e2000-05-02 09:23:45 +1000341 channel_close_fds(c);
Damien Millerb38eff82000-04-01 11:09:21 +1000342 buffer_free(&c->input);
343 buffer_free(&c->output);
344 buffer_free(&c->extended);
Damien Millerb38eff82000-04-01 11:09:21 +1000345 if (c->remote_name) {
346 xfree(c->remote_name);
347 c->remote_name = NULL;
Damien Miller95def091999-11-25 00:26:21 +1100348 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000349 channels[c->self] = NULL;
350 xfree(c);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000351}
352
Ben Lindstrome9c99912001-06-09 00:41:05 +0000353void
Ben Lindstrom601e4362001-06-21 03:19:23 +0000354channel_free_all(void)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000355{
356 int i;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000357
Ben Lindstrom601e4362001-06-21 03:19:23 +0000358 for (i = 0; i < channels_alloc; i++)
359 if (channels[i] != NULL)
360 channel_free(channels[i]);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000361}
362
363/*
364 * Closes the sockets/fds of all channels. This is used to close extra file
365 * descriptors after a fork.
366 */
367
368void
Ben Lindstrom3c36bb22001-12-06 17:55:26 +0000369channel_close_all(void)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000370{
371 int i;
372
373 for (i = 0; i < channels_alloc; i++)
374 if (channels[i] != NULL)
375 channel_close_fds(channels[i]);
376}
377
378/*
Ben Lindstrom809744e2001-07-04 05:26:06 +0000379 * Stop listening to channels.
380 */
381
382void
383channel_stop_listening(void)
384{
385 int i;
386 Channel *c;
387
388 for (i = 0; i < channels_alloc; i++) {
389 c = channels[i];
390 if (c != NULL) {
391 switch (c->type) {
392 case SSH_CHANNEL_AUTH_SOCKET:
393 case SSH_CHANNEL_PORT_LISTENER:
394 case SSH_CHANNEL_RPORT_LISTENER:
395 case SSH_CHANNEL_X11_LISTENER:
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000396 channel_close_fd(&c->sock);
Ben Lindstrom809744e2001-07-04 05:26:06 +0000397 channel_free(c);
398 break;
399 }
400 }
401 }
402}
403
404/*
Ben Lindstrome9c99912001-06-09 00:41:05 +0000405 * Returns true if no channel has too much buffered data, and false if one or
406 * more channel is overfull.
407 */
408
409int
Ben Lindstrom3c36bb22001-12-06 17:55:26 +0000410channel_not_very_much_buffered_data(void)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000411{
412 u_int i;
413 Channel *c;
414
415 for (i = 0; i < channels_alloc; i++) {
416 c = channels[i];
417 if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
Damien Milleraf5f2e62001-10-10 15:01:16 +1000418#if 0
419 if (!compat20 &&
420 buffer_len(&c->input) > packet_get_maxsize()) {
Damien Miller275295e2003-01-08 14:04:09 +1100421 debug2("channel %d: big input buffer %d",
Ben Lindstrome9c99912001-06-09 00:41:05 +0000422 c->self, buffer_len(&c->input));
423 return 0;
424 }
Damien Milleraf5f2e62001-10-10 15:01:16 +1000425#endif
Ben Lindstrome9c99912001-06-09 00:41:05 +0000426 if (buffer_len(&c->output) > packet_get_maxsize()) {
Darren Tucker502d3842003-06-28 12:38:01 +1000427 debug2("channel %d: big output buffer %u > %u",
Damien Milleraf5f2e62001-10-10 15:01:16 +1000428 c->self, buffer_len(&c->output),
429 packet_get_maxsize());
Ben Lindstrome9c99912001-06-09 00:41:05 +0000430 return 0;
431 }
432 }
433 }
434 return 1;
435}
436
437/* Returns true if any channel is still open. */
438
439int
Ben Lindstrom3c36bb22001-12-06 17:55:26 +0000440channel_still_open(void)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000441{
442 int i;
443 Channel *c;
444
445 for (i = 0; i < channels_alloc; i++) {
446 c = channels[i];
447 if (c == NULL)
448 continue;
449 switch (c->type) {
450 case SSH_CHANNEL_X11_LISTENER:
451 case SSH_CHANNEL_PORT_LISTENER:
452 case SSH_CHANNEL_RPORT_LISTENER:
453 case SSH_CHANNEL_CLOSED:
454 case SSH_CHANNEL_AUTH_SOCKET:
455 case SSH_CHANNEL_DYNAMIC:
456 case SSH_CHANNEL_CONNECTING:
457 case SSH_CHANNEL_ZOMBIE:
458 continue;
459 case SSH_CHANNEL_LARVAL:
460 if (!compat20)
461 fatal("cannot happen: SSH_CHANNEL_LARVAL");
462 continue;
463 case SSH_CHANNEL_OPENING:
464 case SSH_CHANNEL_OPEN:
465 case SSH_CHANNEL_X11_OPEN:
466 return 1;
467 case SSH_CHANNEL_INPUT_DRAINING:
468 case SSH_CHANNEL_OUTPUT_DRAINING:
469 if (!compat13)
470 fatal("cannot happen: OUT_DRAIN");
471 return 1;
472 default:
473 fatal("channel_still_open: bad channel type %d", c->type);
474 /* NOTREACHED */
475 }
476 }
477 return 0;
478}
479
480/* Returns the id of an open channel suitable for keepaliving */
481
482int
Ben Lindstrom3c36bb22001-12-06 17:55:26 +0000483channel_find_open(void)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000484{
485 int i;
486 Channel *c;
487
488 for (i = 0; i < channels_alloc; i++) {
489 c = channels[i];
490 if (c == NULL)
491 continue;
492 switch (c->type) {
493 case SSH_CHANNEL_CLOSED:
494 case SSH_CHANNEL_DYNAMIC:
495 case SSH_CHANNEL_X11_LISTENER:
496 case SSH_CHANNEL_PORT_LISTENER:
497 case SSH_CHANNEL_RPORT_LISTENER:
498 case SSH_CHANNEL_OPENING:
499 case SSH_CHANNEL_CONNECTING:
500 case SSH_CHANNEL_ZOMBIE:
501 continue;
502 case SSH_CHANNEL_LARVAL:
503 case SSH_CHANNEL_AUTH_SOCKET:
504 case SSH_CHANNEL_OPEN:
505 case SSH_CHANNEL_X11_OPEN:
506 return i;
507 case SSH_CHANNEL_INPUT_DRAINING:
508 case SSH_CHANNEL_OUTPUT_DRAINING:
509 if (!compat13)
510 fatal("cannot happen: OUT_DRAIN");
511 return i;
512 default:
513 fatal("channel_find_open: bad channel type %d", c->type);
514 /* NOTREACHED */
515 }
516 }
517 return -1;
518}
519
520
521/*
522 * Returns a message describing the currently open forwarded connections,
523 * suitable for sending to the client. The message contains crlf pairs for
524 * newlines.
525 */
526
527char *
Ben Lindstrom3c36bb22001-12-06 17:55:26 +0000528channel_open_message(void)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000529{
530 Buffer buffer;
531 Channel *c;
532 char buf[1024], *cp;
533 int i;
534
535 buffer_init(&buffer);
536 snprintf(buf, sizeof buf, "The following connections are open:\r\n");
537 buffer_append(&buffer, buf, strlen(buf));
538 for (i = 0; i < channels_alloc; i++) {
539 c = channels[i];
540 if (c == NULL)
541 continue;
542 switch (c->type) {
543 case SSH_CHANNEL_X11_LISTENER:
544 case SSH_CHANNEL_PORT_LISTENER:
545 case SSH_CHANNEL_RPORT_LISTENER:
546 case SSH_CHANNEL_CLOSED:
547 case SSH_CHANNEL_AUTH_SOCKET:
548 case SSH_CHANNEL_ZOMBIE:
549 continue;
550 case SSH_CHANNEL_LARVAL:
551 case SSH_CHANNEL_OPENING:
552 case SSH_CHANNEL_CONNECTING:
553 case SSH_CHANNEL_DYNAMIC:
554 case SSH_CHANNEL_OPEN:
555 case SSH_CHANNEL_X11_OPEN:
556 case SSH_CHANNEL_INPUT_DRAINING:
557 case SSH_CHANNEL_OUTPUT_DRAINING:
Damien Miller0e220db2004-06-15 10:34:08 +1000558 snprintf(buf, sizeof buf,
559 " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d cfd %d)\r\n",
Ben Lindstrome9c99912001-06-09 00:41:05 +0000560 c->self, c->remote_name,
561 c->type, c->remote_id,
562 c->istate, buffer_len(&c->input),
563 c->ostate, buffer_len(&c->output),
Damien Miller0e220db2004-06-15 10:34:08 +1000564 c->rfd, c->wfd, c->ctl_fd);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000565 buffer_append(&buffer, buf, strlen(buf));
566 continue;
567 default:
568 fatal("channel_open_message: bad channel type %d", c->type);
569 /* NOTREACHED */
570 }
571 }
572 buffer_append(&buffer, "\0", 1);
573 cp = xstrdup(buffer_ptr(&buffer));
574 buffer_free(&buffer);
575 return cp;
576}
577
578void
579channel_send_open(int id)
580{
581 Channel *c = channel_lookup(id);
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000582
Ben Lindstrome9c99912001-06-09 00:41:05 +0000583 if (c == NULL) {
Damien Miller996acd22003-04-09 20:59:48 +1000584 logit("channel_send_open: %d: bad id", id);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000585 return;
586 }
Ben Lindstrom1d568f92002-12-23 02:44:36 +0000587 debug2("channel %d: send open", id);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000588 packet_start(SSH2_MSG_CHANNEL_OPEN);
589 packet_put_cstring(c->ctype);
590 packet_put_int(c->self);
591 packet_put_int(c->local_window);
592 packet_put_int(c->local_maxpacket);
593 packet_send();
594}
595
596void
Ben Lindstrom1d568f92002-12-23 02:44:36 +0000597channel_request_start(int id, char *service, int wantconfirm)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000598{
Ben Lindstrom1d568f92002-12-23 02:44:36 +0000599 Channel *c = channel_lookup(id);
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000600
Ben Lindstrome9c99912001-06-09 00:41:05 +0000601 if (c == NULL) {
Damien Miller996acd22003-04-09 20:59:48 +1000602 logit("channel_request_start: %d: unknown channel id", id);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000603 return;
604 }
Damien Miller0e220db2004-06-15 10:34:08 +1000605 debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000606 packet_start(SSH2_MSG_CHANNEL_REQUEST);
607 packet_put_int(c->remote_id);
608 packet_put_cstring(service);
609 packet_put_char(wantconfirm);
610}
611void
Damien Miller0e220db2004-06-15 10:34:08 +1000612channel_register_confirm(int id, channel_callback_fn *fn, void *ctx)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000613{
614 Channel *c = channel_lookup(id);
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000615
Ben Lindstrome9c99912001-06-09 00:41:05 +0000616 if (c == NULL) {
Damien Miller996acd22003-04-09 20:59:48 +1000617 logit("channel_register_comfirm: %d: bad id", id);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000618 return;
619 }
Damien Miller67f0bc02002-02-05 12:23:08 +1100620 c->confirm = fn;
Damien Miller0e220db2004-06-15 10:34:08 +1000621 c->confirm_ctx = ctx;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000622}
623void
624channel_register_cleanup(int id, channel_callback_fn *fn)
625{
626 Channel *c = channel_lookup(id);
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000627
Ben Lindstrome9c99912001-06-09 00:41:05 +0000628 if (c == NULL) {
Damien Miller996acd22003-04-09 20:59:48 +1000629 logit("channel_register_cleanup: %d: bad id", id);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000630 return;
631 }
Ben Lindstrom809744e2001-07-04 05:26:06 +0000632 c->detach_user = fn;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000633}
634void
635channel_cancel_cleanup(int id)
636{
637 Channel *c = channel_lookup(id);
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000638
Ben Lindstrome9c99912001-06-09 00:41:05 +0000639 if (c == NULL) {
Damien Miller996acd22003-04-09 20:59:48 +1000640 logit("channel_cancel_cleanup: %d: bad id", id);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000641 return;
642 }
Ben Lindstrom809744e2001-07-04 05:26:06 +0000643 c->detach_user = NULL;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000644}
645void
646channel_register_filter(int id, channel_filter_fn *fn)
647{
648 Channel *c = channel_lookup(id);
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000649
Ben Lindstrome9c99912001-06-09 00:41:05 +0000650 if (c == NULL) {
Damien Miller996acd22003-04-09 20:59:48 +1000651 logit("channel_register_filter: %d: bad id", id);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000652 return;
653 }
654 c->input_filter = fn;
655}
656
657void
658channel_set_fds(int id, int rfd, int wfd, int efd,
Damien Miller2aa0c192002-02-19 15:20:08 +1100659 int extusage, int nonblock, u_int window_max)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000660{
661 Channel *c = channel_lookup(id);
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000662
Ben Lindstrome9c99912001-06-09 00:41:05 +0000663 if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
664 fatal("channel_activate for non-larval channel %d.", id);
665 channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
666 c->type = SSH_CHANNEL_OPEN;
Damien Miller2aa0c192002-02-19 15:20:08 +1100667 c->local_window = c->local_window_max = window_max;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000668 packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
669 packet_put_int(c->remote_id);
670 packet_put_int(c->local_window);
671 packet_send();
672}
673
Damien Miller5428f641999-11-25 11:54:57 +1100674/*
Damien Millerb38eff82000-04-01 11:09:21 +1000675 * 'channel_pre*' are called just before select() to add any bits relevant to
676 * channels in the select bitmasks.
Damien Miller5428f641999-11-25 11:54:57 +1100677 */
Damien Millerb38eff82000-04-01 11:09:21 +1000678/*
679 * 'channel_post*': perform any appropriate operations for channels which
680 * have events pending.
681 */
682typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset);
683chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
684chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
685
Ben Lindstrombba81212001-06-25 05:01:22 +0000686static void
Damien Millerb38eff82000-04-01 11:09:21 +1000687channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset)
688{
689 FD_SET(c->sock, readset);
690}
691
Ben Lindstrombba81212001-06-25 05:01:22 +0000692static void
Ben Lindstrom7ad97102000-12-06 01:42:49 +0000693channel_pre_connecting(Channel *c, fd_set * readset, fd_set * writeset)
694{
695 debug3("channel %d: waiting for connection", c->self);
696 FD_SET(c->sock, writeset);
697}
698
Ben Lindstrombba81212001-06-25 05:01:22 +0000699static void
Damien Millerb38eff82000-04-01 11:09:21 +1000700channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset)
701{
702 if (buffer_len(&c->input) < packet_get_maxsize())
703 FD_SET(c->sock, readset);
704 if (buffer_len(&c->output) > 0)
705 FD_SET(c->sock, writeset);
706}
707
Ben Lindstrombba81212001-06-25 05:01:22 +0000708static void
Damien Millerde6987c2002-01-22 23:20:40 +1100709channel_pre_open(Channel *c, fd_set * readset, fd_set * writeset)
Damien Millerb38eff82000-04-01 11:09:21 +1000710{
Damien Millerde6987c2002-01-22 23:20:40 +1100711 u_int limit = compat20 ? c->remote_window : packet_get_maxsize();
Damien Millerb38eff82000-04-01 11:09:21 +1000712
Damien Miller33b13562000-04-04 14:38:59 +1000713 if (c->istate == CHAN_INPUT_OPEN &&
Damien Millerde6987c2002-01-22 23:20:40 +1100714 limit > 0 &&
715 buffer_len(&c->input) < limit)
Damien Miller33b13562000-04-04 14:38:59 +1000716 FD_SET(c->rfd, readset);
717 if (c->ostate == CHAN_OUTPUT_OPEN ||
718 c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
719 if (buffer_len(&c->output) > 0) {
720 FD_SET(c->wfd, writeset);
721 } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
Ben Lindstromcf159442002-03-26 03:26:24 +0000722 if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
Ben Lindstrom5a6abda2002-06-09 19:41:48 +0000723 debug2("channel %d: obuf_empty delayed efd %d/(%d)",
724 c->self, c->efd, buffer_len(&c->extended));
Ben Lindstromcf159442002-03-26 03:26:24 +0000725 else
726 chan_obuf_empty(c);
Damien Miller33b13562000-04-04 14:38:59 +1000727 }
728 }
729 /** XXX check close conditions, too */
Damien Millerde6987c2002-01-22 23:20:40 +1100730 if (compat20 && c->efd != -1) {
Damien Miller33b13562000-04-04 14:38:59 +1000731 if (c->extended_usage == CHAN_EXTENDED_WRITE &&
732 buffer_len(&c->extended) > 0)
733 FD_SET(c->efd, writeset);
Ben Lindstromcf159442002-03-26 03:26:24 +0000734 else if (!(c->flags & CHAN_EOF_SENT) &&
735 c->extended_usage == CHAN_EXTENDED_READ &&
Damien Miller33b13562000-04-04 14:38:59 +1000736 buffer_len(&c->extended) < c->remote_window)
737 FD_SET(c->efd, readset);
738 }
Damien Miller0e220db2004-06-15 10:34:08 +1000739 /* XXX: What about efd? races? */
740 if (compat20 && c->ctl_fd != -1 &&
741 c->istate == CHAN_INPUT_OPEN && c->ostate == CHAN_OUTPUT_OPEN)
742 FD_SET(c->ctl_fd, readset);
Damien Miller33b13562000-04-04 14:38:59 +1000743}
744
Ben Lindstrombba81212001-06-25 05:01:22 +0000745static void
Damien Millerb38eff82000-04-01 11:09:21 +1000746channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset)
747{
748 if (buffer_len(&c->input) == 0) {
749 packet_start(SSH_MSG_CHANNEL_CLOSE);
750 packet_put_int(c->remote_id);
751 packet_send();
752 c->type = SSH_CHANNEL_CLOSED;
Damien Millerfbdeece2003-09-02 22:52:31 +1000753 debug2("channel %d: closing after input drain.", c->self);
Damien Millerb38eff82000-04-01 11:09:21 +1000754 }
755}
756
Ben Lindstrombba81212001-06-25 05:01:22 +0000757static void
Damien Millerb38eff82000-04-01 11:09:21 +1000758channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset)
759{
760 if (buffer_len(&c->output) == 0)
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000761 chan_mark_dead(c);
Damien Miller4af51302000-04-16 11:18:38 +1000762 else
Damien Millerb38eff82000-04-01 11:09:21 +1000763 FD_SET(c->sock, writeset);
764}
765
766/*
767 * This is a special state for X11 authentication spoofing. An opened X11
768 * connection (when authentication spoofing is being done) remains in this
769 * state until the first packet has been completely read. The authentication
770 * data in that packet is then substituted by the real data if it matches the
771 * fake data, and the channel is put into normal mode.
Damien Millerbd483e72000-04-30 10:00:53 +1000772 * XXX All this happens at the client side.
Ben Lindstrome9c99912001-06-09 00:41:05 +0000773 * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
Damien Millerb38eff82000-04-01 11:09:21 +1000774 */
Ben Lindstrombba81212001-06-25 05:01:22 +0000775static int
Ben Lindstrome9c99912001-06-09 00:41:05 +0000776x11_open_helper(Buffer *b)
Damien Millerb38eff82000-04-01 11:09:21 +1000777{
Ben Lindstrom46c16222000-12-22 01:43:59 +0000778 u_char *ucp;
779 u_int proto_len, data_len;
Damien Millerb38eff82000-04-01 11:09:21 +1000780
781 /* Check if the fixed size part of the packet is in buffer. */
Ben Lindstrome9c99912001-06-09 00:41:05 +0000782 if (buffer_len(b) < 12)
Damien Millerb38eff82000-04-01 11:09:21 +1000783 return 0;
784
785 /* Parse the lengths of variable-length fields. */
Damien Miller708d21c2002-01-22 23:18:15 +1100786 ucp = buffer_ptr(b);
Damien Millerb38eff82000-04-01 11:09:21 +1000787 if (ucp[0] == 0x42) { /* Byte order MSB first. */
788 proto_len = 256 * ucp[6] + ucp[7];
789 data_len = 256 * ucp[8] + ucp[9];
790 } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
791 proto_len = ucp[6] + 256 * ucp[7];
792 data_len = ucp[8] + 256 * ucp[9];
793 } else {
Damien Millerfbdeece2003-09-02 22:52:31 +1000794 debug2("Initial X11 packet contains bad byte order byte: 0x%x",
Damien Miller9f0f5c62001-12-21 14:45:46 +1100795 ucp[0]);
Damien Millerb38eff82000-04-01 11:09:21 +1000796 return -1;
797 }
798
799 /* Check if the whole packet is in buffer. */
Ben Lindstrome9c99912001-06-09 00:41:05 +0000800 if (buffer_len(b) <
Damien Millerb38eff82000-04-01 11:09:21 +1000801 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
802 return 0;
803
804 /* Check if authentication protocol matches. */
805 if (proto_len != strlen(x11_saved_proto) ||
806 memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
Damien Millerfbdeece2003-09-02 22:52:31 +1000807 debug2("X11 connection uses different authentication protocol.");
Damien Millerb38eff82000-04-01 11:09:21 +1000808 return -1;
809 }
810 /* Check if authentication data matches our fake data. */
811 if (data_len != x11_fake_data_len ||
812 memcmp(ucp + 12 + ((proto_len + 3) & ~3),
813 x11_fake_data, x11_fake_data_len) != 0) {
Damien Millerfbdeece2003-09-02 22:52:31 +1000814 debug2("X11 auth data does not match fake data.");
Damien Millerb38eff82000-04-01 11:09:21 +1000815 return -1;
816 }
817 /* Check fake data length */
818 if (x11_fake_data_len != x11_saved_data_len) {
819 error("X11 fake_data_len %d != saved_data_len %d",
820 x11_fake_data_len, x11_saved_data_len);
821 return -1;
822 }
823 /*
824 * Received authentication protocol and data match
825 * our fake data. Substitute the fake data with real
826 * data.
827 */
828 memcpy(ucp + 12 + ((proto_len + 3) & ~3),
829 x11_saved_data, x11_saved_data_len);
830 return 1;
831}
832
Ben Lindstrombba81212001-06-25 05:01:22 +0000833static void
Damien Millerb38eff82000-04-01 11:09:21 +1000834channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset)
835{
Ben Lindstrome9c99912001-06-09 00:41:05 +0000836 int ret = x11_open_helper(&c->output);
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000837
Damien Millerb38eff82000-04-01 11:09:21 +1000838 if (ret == 1) {
839 /* Start normal processing for the channel. */
840 c->type = SSH_CHANNEL_OPEN;
Damien Miller78928792000-04-12 20:17:38 +1000841 channel_pre_open_13(c, readset, writeset);
Damien Millerb38eff82000-04-01 11:09:21 +1000842 } else if (ret == -1) {
843 /*
844 * We have received an X11 connection that has bad
845 * authentication information.
846 */
Damien Miller996acd22003-04-09 20:59:48 +1000847 logit("X11 connection rejected because of wrong authentication.");
Damien Millerb38eff82000-04-01 11:09:21 +1000848 buffer_clear(&c->input);
849 buffer_clear(&c->output);
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000850 channel_close_fd(&c->sock);
Damien Millerb38eff82000-04-01 11:09:21 +1000851 c->sock = -1;
852 c->type = SSH_CHANNEL_CLOSED;
853 packet_start(SSH_MSG_CHANNEL_CLOSE);
854 packet_put_int(c->remote_id);
855 packet_send();
856 }
857}
858
Ben Lindstrombba81212001-06-25 05:01:22 +0000859static void
Damien Millerbd483e72000-04-30 10:00:53 +1000860channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset)
Damien Millerb38eff82000-04-01 11:09:21 +1000861{
Ben Lindstrome9c99912001-06-09 00:41:05 +0000862 int ret = x11_open_helper(&c->output);
Ben Lindstrom944c4f02001-09-18 05:51:13 +0000863
864 /* c->force_drain = 1; */
865
Damien Millerb38eff82000-04-01 11:09:21 +1000866 if (ret == 1) {
867 c->type = SSH_CHANNEL_OPEN;
Damien Millerde6987c2002-01-22 23:20:40 +1100868 channel_pre_open(c, readset, writeset);
Damien Millerb38eff82000-04-01 11:09:21 +1000869 } else if (ret == -1) {
Damien Miller996acd22003-04-09 20:59:48 +1000870 logit("X11 connection rejected because of wrong authentication.");
Damien Millerfbdeece2003-09-02 22:52:31 +1000871 debug2("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
Damien Millera90fc082002-01-22 23:19:38 +1100872 chan_read_failed(c);
873 buffer_clear(&c->input);
874 chan_ibuf_empty(c);
875 buffer_clear(&c->output);
876 /* for proto v1, the peer will send an IEOF */
877 if (compat20)
878 chan_write_failed(c);
879 else
880 c->type = SSH_CHANNEL_OPEN;
Damien Millerfbdeece2003-09-02 22:52:31 +1000881 debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
Damien Millerb38eff82000-04-01 11:09:21 +1000882 }
883}
884
Ben Lindstromb3921512001-04-11 15:57:50 +0000885/* try to decode a socks4 header */
Ben Lindstrombba81212001-06-25 05:01:22 +0000886static int
Ben Lindstromb3921512001-04-11 15:57:50 +0000887channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset)
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000888{
Damien Millera10f5612002-09-12 09:49:15 +1000889 char *p, *host;
Ben Lindstrom2b261b92001-04-17 18:14:34 +0000890 int len, have, i, found;
Damien Miller9f0f5c62001-12-21 14:45:46 +1100891 char username[256];
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000892 struct {
893 u_int8_t version;
894 u_int8_t command;
895 u_int16_t dest_port;
Ben Lindstromb3921512001-04-11 15:57:50 +0000896 struct in_addr dest_addr;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000897 } s4_req, s4_rsp;
898
Ben Lindstromb3921512001-04-11 15:57:50 +0000899 debug2("channel %d: decode socks4", c->self);
Ben Lindstrom2b261b92001-04-17 18:14:34 +0000900
901 have = buffer_len(&c->input);
902 len = sizeof(s4_req);
903 if (have < len)
904 return 0;
905 p = buffer_ptr(&c->input);
906 for (found = 0, i = len; i < have; i++) {
907 if (p[i] == '\0') {
908 found = 1;
909 break;
910 }
911 if (i > 1024) {
912 /* the peer is probably sending garbage */
913 debug("channel %d: decode socks4: too long",
914 c->self);
915 return -1;
916 }
917 }
918 if (!found)
919 return 0;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000920 buffer_get(&c->input, (char *)&s4_req.version, 1);
921 buffer_get(&c->input, (char *)&s4_req.command, 1);
922 buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
Ben Lindstromb3921512001-04-11 15:57:50 +0000923 buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
Ben Lindstrom2b261b92001-04-17 18:14:34 +0000924 have = buffer_len(&c->input);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000925 p = buffer_ptr(&c->input);
926 len = strlen(p);
Ben Lindstrom6fa9d102001-04-11 23:08:17 +0000927 debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000928 if (len > have)
Ben Lindstromb3921512001-04-11 15:57:50 +0000929 fatal("channel %d: decode socks4: len %d > have %d",
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000930 c->self, len, have);
931 strlcpy(username, p, sizeof(username));
932 buffer_consume(&c->input, len);
933 buffer_consume(&c->input, 1); /* trailing '\0' */
934
Ben Lindstromb3921512001-04-11 15:57:50 +0000935 host = inet_ntoa(s4_req.dest_addr);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000936 strlcpy(c->path, host, sizeof(c->path));
937 c->host_port = ntohs(s4_req.dest_port);
Damien Miller9f0f5c62001-12-21 14:45:46 +1100938
Damien Millerfbdeece2003-09-02 22:52:31 +1000939 debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
Ben Lindstrom6fa9d102001-04-11 23:08:17 +0000940 c->self, host, c->host_port, s4_req.command);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000941
Ben Lindstromb3921512001-04-11 15:57:50 +0000942 if (s4_req.command != 1) {
943 debug("channel %d: cannot handle: socks4 cn %d",
944 c->self, s4_req.command);
945 return -1;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000946 }
Ben Lindstromb3921512001-04-11 15:57:50 +0000947 s4_rsp.version = 0; /* vn: 0 for reply */
948 s4_rsp.command = 90; /* cd: req granted */
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000949 s4_rsp.dest_port = 0; /* ignored */
Ben Lindstromb3921512001-04-11 15:57:50 +0000950 s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000951 buffer_append(&c->output, (char *)&s4_rsp, sizeof(s4_rsp));
Ben Lindstromb3921512001-04-11 15:57:50 +0000952 return 1;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000953}
954
Darren Tucker46471c92003-07-03 13:55:19 +1000955/* try to decode a socks5 header */
956#define SSH_SOCKS5_AUTHDONE 0x1000
957#define SSH_SOCKS5_NOAUTH 0x00
958#define SSH_SOCKS5_IPV4 0x01
959#define SSH_SOCKS5_DOMAIN 0x03
960#define SSH_SOCKS5_IPV6 0x04
961#define SSH_SOCKS5_CONNECT 0x01
962#define SSH_SOCKS5_SUCCESS 0x00
963
964static int
965channel_decode_socks5(Channel *c, fd_set * readset, fd_set * writeset)
966{
967 struct {
968 u_int8_t version;
969 u_int8_t command;
970 u_int8_t reserved;
971 u_int8_t atyp;
972 } s5_req, s5_rsp;
973 u_int16_t dest_port;
974 u_char *p, dest_addr[255+1];
975 int i, have, found, nmethods, addrlen, af;
976
977 debug2("channel %d: decode socks5", c->self);
978 p = buffer_ptr(&c->input);
979 if (p[0] != 0x05)
980 return -1;
981 have = buffer_len(&c->input);
982 if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
983 /* format: ver | nmethods | methods */
Damien Millera8e06ce2003-11-21 23:48:55 +1100984 if (have < 2)
Darren Tucker46471c92003-07-03 13:55:19 +1000985 return 0;
986 nmethods = p[1];
987 if (have < nmethods + 2)
988 return 0;
989 /* look for method: "NO AUTHENTICATION REQUIRED" */
990 for (found = 0, i = 2 ; i < nmethods + 2; i++) {
991 if (p[i] == SSH_SOCKS5_NOAUTH ) {
992 found = 1;
993 break;
994 }
995 }
996 if (!found) {
997 debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
998 c->self);
999 return -1;
1000 }
1001 buffer_consume(&c->input, nmethods + 2);
1002 buffer_put_char(&c->output, 0x05); /* version */
1003 buffer_put_char(&c->output, SSH_SOCKS5_NOAUTH); /* method */
1004 FD_SET(c->sock, writeset);
1005 c->flags |= SSH_SOCKS5_AUTHDONE;
1006 debug2("channel %d: socks5 auth done", c->self);
1007 return 0; /* need more */
1008 }
1009 debug2("channel %d: socks5 post auth", c->self);
1010 if (have < sizeof(s5_req)+1)
1011 return 0; /* need more */
1012 memcpy((char *)&s5_req, p, sizeof(s5_req));
1013 if (s5_req.version != 0x05 ||
1014 s5_req.command != SSH_SOCKS5_CONNECT ||
1015 s5_req.reserved != 0x00) {
Damien Millerfbdeece2003-09-02 22:52:31 +10001016 debug2("channel %d: only socks5 connect supported", c->self);
Darren Tucker46471c92003-07-03 13:55:19 +10001017 return -1;
1018 }
1019 switch(s5_req.atyp){
1020 case SSH_SOCKS5_IPV4:
1021 addrlen = 4;
1022 af = AF_INET;
1023 break;
1024 case SSH_SOCKS5_DOMAIN:
1025 addrlen = p[sizeof(s5_req)];
1026 af = -1;
1027 break;
1028 case SSH_SOCKS5_IPV6:
1029 addrlen = 16;
1030 af = AF_INET6;
1031 break;
1032 default:
Damien Millerfbdeece2003-09-02 22:52:31 +10001033 debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
Darren Tucker46471c92003-07-03 13:55:19 +10001034 return -1;
1035 }
1036 if (have < 4 + addrlen + 2)
1037 return 0;
1038 buffer_consume(&c->input, sizeof(s5_req));
1039 if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1040 buffer_consume(&c->input, 1); /* host string length */
1041 buffer_get(&c->input, (char *)&dest_addr, addrlen);
1042 buffer_get(&c->input, (char *)&dest_port, 2);
1043 dest_addr[addrlen] = '\0';
1044 if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
Darren Tucker1f8311c2004-05-13 16:39:33 +10001045 strlcpy(c->path, (char *)dest_addr, sizeof(c->path));
Darren Tucker46471c92003-07-03 13:55:19 +10001046 else if (inet_ntop(af, dest_addr, c->path, sizeof(c->path)) == NULL)
1047 return -1;
1048 c->host_port = ntohs(dest_port);
Damien Miller787b2ec2003-11-21 23:56:47 +11001049
Damien Millerfbdeece2003-09-02 22:52:31 +10001050 debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
Darren Tucker46471c92003-07-03 13:55:19 +10001051 c->self, c->path, c->host_port, s5_req.command);
1052
1053 s5_rsp.version = 0x05;
1054 s5_rsp.command = SSH_SOCKS5_SUCCESS;
1055 s5_rsp.reserved = 0; /* ignored */
1056 s5_rsp.atyp = SSH_SOCKS5_IPV4;
1057 ((struct in_addr *)&dest_addr)->s_addr = INADDR_ANY;
1058 dest_port = 0; /* ignored */
1059
1060 buffer_append(&c->output, (char *)&s5_rsp, sizeof(s5_rsp));
1061 buffer_append(&c->output, (char *)&dest_addr, sizeof(struct in_addr));
1062 buffer_append(&c->output, (char *)&dest_port, sizeof(dest_port));
1063 return 1;
1064}
1065
Ben Lindstromb3921512001-04-11 15:57:50 +00001066/* dynamic port forwarding */
Ben Lindstrombba81212001-06-25 05:01:22 +00001067static void
Ben Lindstromb3921512001-04-11 15:57:50 +00001068channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset)
1069{
1070 u_char *p;
1071 int have, ret;
1072
1073 have = buffer_len(&c->input);
Damien Miller4623a752001-10-10 15:03:58 +10001074 c->delayed = 0;
Ben Lindstromb3921512001-04-11 15:57:50 +00001075 debug2("channel %d: pre_dynamic: have %d", c->self, have);
Ben Lindstromc486d882001-04-11 16:08:34 +00001076 /* buffer_dump(&c->input); */
Ben Lindstromb3921512001-04-11 15:57:50 +00001077 /* check if the fixed size part of the packet is in buffer. */
Darren Tucker46471c92003-07-03 13:55:19 +10001078 if (have < 3) {
Ben Lindstromb3921512001-04-11 15:57:50 +00001079 /* need more */
1080 FD_SET(c->sock, readset);
1081 return;
1082 }
1083 /* try to guess the protocol */
1084 p = buffer_ptr(&c->input);
1085 switch (p[0]) {
Ben Lindstrom6fa9d102001-04-11 23:08:17 +00001086 case 0x04:
1087 ret = channel_decode_socks4(c, readset, writeset);
1088 break;
Darren Tucker46471c92003-07-03 13:55:19 +10001089 case 0x05:
1090 ret = channel_decode_socks5(c, readset, writeset);
1091 break;
Ben Lindstromb3921512001-04-11 15:57:50 +00001092 default:
1093 ret = -1;
1094 break;
1095 }
1096 if (ret < 0) {
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001097 chan_mark_dead(c);
Ben Lindstromb3921512001-04-11 15:57:50 +00001098 } else if (ret == 0) {
1099 debug2("channel %d: pre_dynamic: need more", c->self);
1100 /* need more */
1101 FD_SET(c->sock, readset);
1102 } else {
1103 /* switch to the next state */
1104 c->type = SSH_CHANNEL_OPENING;
1105 port_open_helper(c, "direct-tcpip");
1106 }
1107}
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001108
Damien Millerb38eff82000-04-01 11:09:21 +10001109/* This is our fake X11 server socket. */
Ben Lindstrombba81212001-06-25 05:01:22 +00001110static void
Damien Millerb38eff82000-04-01 11:09:21 +10001111channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset)
1112{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001113 Channel *nc;
Damien Millerb38eff82000-04-01 11:09:21 +10001114 struct sockaddr addr;
Damien Miller398e1cf2002-02-05 11:52:13 +11001115 int newsock;
Damien Millerb38eff82000-04-01 11:09:21 +10001116 socklen_t addrlen;
Damien Millerd83ff352001-01-30 09:19:34 +11001117 char buf[16384], *remote_ipaddr;
Damien Millerbd483e72000-04-30 10:00:53 +10001118 int remote_port;
Damien Millerb38eff82000-04-01 11:09:21 +10001119
1120 if (FD_ISSET(c->sock, readset)) {
1121 debug("X11 connection requested.");
1122 addrlen = sizeof(addr);
1123 newsock = accept(c->sock, &addr, &addrlen);
Damien Millere7378562001-12-21 14:58:35 +11001124 if (c->single_connection) {
Damien Millerfbdeece2003-09-02 22:52:31 +10001125 debug2("single_connection: closing X11 listener.");
Damien Millere7378562001-12-21 14:58:35 +11001126 channel_close_fd(&c->sock);
1127 chan_mark_dead(c);
1128 }
Damien Millerb38eff82000-04-01 11:09:21 +10001129 if (newsock < 0) {
1130 error("accept: %.100s", strerror(errno));
1131 return;
1132 }
Damien Miller398e1cf2002-02-05 11:52:13 +11001133 set_nodelay(newsock);
Damien Millerd83ff352001-01-30 09:19:34 +11001134 remote_ipaddr = get_peer_ipaddr(newsock);
Damien Millerbd483e72000-04-30 10:00:53 +10001135 remote_port = get_peer_port(newsock);
Damien Millerb38eff82000-04-01 11:09:21 +10001136 snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
Damien Millerd83ff352001-01-30 09:19:34 +11001137 remote_ipaddr, remote_port);
Damien Millerbd483e72000-04-30 10:00:53 +10001138
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001139 nc = channel_new("accepted x11 socket",
Damien Millerbd483e72000-04-30 10:00:53 +10001140 SSH_CHANNEL_OPENING, newsock, newsock, -1,
Damien Millerb1ca8bb2003-05-14 13:45:42 +10001141 c->local_window_max, c->local_maxpacket, 0, buf, 1);
Damien Millerbd483e72000-04-30 10:00:53 +10001142 if (compat20) {
1143 packet_start(SSH2_MSG_CHANNEL_OPEN);
1144 packet_put_cstring("x11");
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001145 packet_put_int(nc->self);
Damien Millere7378562001-12-21 14:58:35 +11001146 packet_put_int(nc->local_window_max);
1147 packet_put_int(nc->local_maxpacket);
Damien Millerd83ff352001-01-30 09:19:34 +11001148 /* originator ipaddr and port */
1149 packet_put_cstring(remote_ipaddr);
Damien Miller30c3d422000-05-09 11:02:59 +10001150 if (datafellows & SSH_BUG_X11FWD) {
Damien Millerfbdeece2003-09-02 22:52:31 +10001151 debug2("ssh2 x11 bug compat mode");
Damien Miller30c3d422000-05-09 11:02:59 +10001152 } else {
1153 packet_put_int(remote_port);
1154 }
Damien Millerbd483e72000-04-30 10:00:53 +10001155 packet_send();
1156 } else {
1157 packet_start(SSH_SMSG_X11_OPEN);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001158 packet_put_int(nc->self);
Ben Lindstrome9c99912001-06-09 00:41:05 +00001159 if (packet_get_protocol_flags() &
1160 SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
Ben Lindstrom664408d2001-06-09 01:42:01 +00001161 packet_put_cstring(buf);
Damien Millerbd483e72000-04-30 10:00:53 +10001162 packet_send();
1163 }
Damien Millerd83ff352001-01-30 09:19:34 +11001164 xfree(remote_ipaddr);
Damien Millerb38eff82000-04-01 11:09:21 +10001165 }
1166}
1167
Ben Lindstrombba81212001-06-25 05:01:22 +00001168static void
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001169port_open_helper(Channel *c, char *rtype)
1170{
1171 int direct;
1172 char buf[1024];
1173 char *remote_ipaddr = get_peer_ipaddr(c->sock);
1174 u_short remote_port = get_peer_port(c->sock);
1175
1176 direct = (strcmp(rtype, "direct-tcpip") == 0);
1177
1178 snprintf(buf, sizeof buf,
1179 "%s: listening port %d for %.100s port %d, "
1180 "connect from %.200s port %d",
1181 rtype, c->listening_port, c->path, c->host_port,
1182 remote_ipaddr, remote_port);
1183
1184 xfree(c->remote_name);
1185 c->remote_name = xstrdup(buf);
1186
1187 if (compat20) {
1188 packet_start(SSH2_MSG_CHANNEL_OPEN);
1189 packet_put_cstring(rtype);
1190 packet_put_int(c->self);
1191 packet_put_int(c->local_window_max);
1192 packet_put_int(c->local_maxpacket);
1193 if (direct) {
1194 /* target host, port */
1195 packet_put_cstring(c->path);
1196 packet_put_int(c->host_port);
1197 } else {
1198 /* listen address, port */
1199 packet_put_cstring(c->path);
1200 packet_put_int(c->listening_port);
1201 }
1202 /* originator host and port */
1203 packet_put_cstring(remote_ipaddr);
1204 packet_put_int(remote_port);
1205 packet_send();
1206 } else {
1207 packet_start(SSH_MSG_PORT_OPEN);
1208 packet_put_int(c->self);
1209 packet_put_cstring(c->path);
1210 packet_put_int(c->host_port);
Ben Lindstrome9c99912001-06-09 00:41:05 +00001211 if (packet_get_protocol_flags() &
1212 SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001213 packet_put_cstring(c->remote_name);
1214 packet_send();
1215 }
1216 xfree(remote_ipaddr);
1217}
1218
Damien Millerb38eff82000-04-01 11:09:21 +10001219/*
1220 * This socket is listening for connections to a forwarded TCP/IP port.
1221 */
Ben Lindstrombba81212001-06-25 05:01:22 +00001222static void
Damien Millerb38eff82000-04-01 11:09:21 +10001223channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset)
1224{
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001225 Channel *nc;
Damien Millerb38eff82000-04-01 11:09:21 +10001226 struct sockaddr addr;
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001227 int newsock, nextstate;
Damien Millerb38eff82000-04-01 11:09:21 +10001228 socklen_t addrlen;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001229 char *rtype;
Damien Miller0bc1bd82000-11-13 22:57:25 +11001230
Damien Millerb38eff82000-04-01 11:09:21 +10001231 if (FD_ISSET(c->sock, readset)) {
1232 debug("Connection to port %d forwarding "
1233 "to %.100s port %d requested.",
1234 c->listening_port, c->path, c->host_port);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001235
Damien Miller4623a752001-10-10 15:03:58 +10001236 if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1237 nextstate = SSH_CHANNEL_OPENING;
1238 rtype = "forwarded-tcpip";
1239 } else {
1240 if (c->host_port == 0) {
1241 nextstate = SSH_CHANNEL_DYNAMIC;
Damien Millerd3c04b92001-10-10 15:04:20 +10001242 rtype = "dynamic-tcpip";
Damien Miller4623a752001-10-10 15:03:58 +10001243 } else {
1244 nextstate = SSH_CHANNEL_OPENING;
1245 rtype = "direct-tcpip";
1246 }
1247 }
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001248
Damien Millerb38eff82000-04-01 11:09:21 +10001249 addrlen = sizeof(addr);
1250 newsock = accept(c->sock, &addr, &addrlen);
1251 if (newsock < 0) {
1252 error("accept: %.100s", strerror(errno));
1253 return;
1254 }
Ben Lindstrom1ebd7a52002-02-26 18:12:51 +00001255 set_nodelay(newsock);
Damien Millerb1ca8bb2003-05-14 13:45:42 +10001256 nc = channel_new(rtype, nextstate, newsock, newsock, -1,
1257 c->local_window_max, c->local_maxpacket, 0, rtype, 1);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001258 nc->listening_port = c->listening_port;
1259 nc->host_port = c->host_port;
1260 strlcpy(nc->path, c->path, sizeof(nc->path));
1261
Damien Miller4623a752001-10-10 15:03:58 +10001262 if (nextstate == SSH_CHANNEL_DYNAMIC) {
1263 /*
1264 * do not call the channel_post handler until
1265 * this flag has been reset by a pre-handler.
1266 * otherwise the FD_ISSET calls might overflow
1267 */
1268 nc->delayed = 1;
1269 } else {
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001270 port_open_helper(nc, rtype);
Damien Miller4623a752001-10-10 15:03:58 +10001271 }
Damien Millerb38eff82000-04-01 11:09:21 +10001272 }
1273}
1274
1275/*
1276 * This is the authentication agent socket listening for connections from
1277 * clients.
1278 */
Ben Lindstrombba81212001-06-25 05:01:22 +00001279static void
Damien Millerb38eff82000-04-01 11:09:21 +10001280channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset)
1281{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001282 Channel *nc;
1283 int newsock;
Damien Millerb38eff82000-04-01 11:09:21 +10001284 struct sockaddr addr;
Damien Millerb38eff82000-04-01 11:09:21 +10001285 socklen_t addrlen;
1286
1287 if (FD_ISSET(c->sock, readset)) {
1288 addrlen = sizeof(addr);
1289 newsock = accept(c->sock, &addr, &addrlen);
1290 if (newsock < 0) {
1291 error("accept from auth socket: %.100s", strerror(errno));
1292 return;
1293 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001294 nc = channel_new("accepted auth socket",
Damien Miller0bc1bd82000-11-13 22:57:25 +11001295 SSH_CHANNEL_OPENING, newsock, newsock, -1,
1296 c->local_window_max, c->local_maxpacket,
Damien Millerb1ca8bb2003-05-14 13:45:42 +10001297 0, "accepted auth socket", 1);
Damien Miller0bc1bd82000-11-13 22:57:25 +11001298 if (compat20) {
1299 packet_start(SSH2_MSG_CHANNEL_OPEN);
1300 packet_put_cstring("auth-agent@openssh.com");
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001301 packet_put_int(nc->self);
Damien Miller0bc1bd82000-11-13 22:57:25 +11001302 packet_put_int(c->local_window_max);
1303 packet_put_int(c->local_maxpacket);
1304 } else {
1305 packet_start(SSH_SMSG_AGENT_OPEN);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001306 packet_put_int(nc->self);
Damien Miller0bc1bd82000-11-13 22:57:25 +11001307 }
Damien Millerb38eff82000-04-01 11:09:21 +10001308 packet_send();
1309 }
1310}
1311
Ben Lindstrombba81212001-06-25 05:01:22 +00001312static void
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001313channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset)
1314{
Ben Lindstrom69128662001-05-08 20:07:39 +00001315 int err = 0;
Ben Lindstrom11180952001-07-04 05:13:35 +00001316 socklen_t sz = sizeof(err);
Ben Lindstrom69128662001-05-08 20:07:39 +00001317
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001318 if (FD_ISSET(c->sock, writeset)) {
Ben Lindstrom733a2352002-03-05 01:31:28 +00001319 if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
Ben Lindstrom69128662001-05-08 20:07:39 +00001320 err = errno;
1321 error("getsockopt SO_ERROR failed");
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001322 }
Ben Lindstrom69128662001-05-08 20:07:39 +00001323 if (err == 0) {
1324 debug("channel %d: connected", c->self);
1325 c->type = SSH_CHANNEL_OPEN;
1326 if (compat20) {
1327 packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1328 packet_put_int(c->remote_id);
1329 packet_put_int(c->self);
1330 packet_put_int(c->local_window);
1331 packet_put_int(c->local_maxpacket);
1332 } else {
1333 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1334 packet_put_int(c->remote_id);
1335 packet_put_int(c->self);
1336 }
1337 } else {
1338 debug("channel %d: not connected: %s",
1339 c->self, strerror(err));
1340 if (compat20) {
1341 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1342 packet_put_int(c->remote_id);
1343 packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1344 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1345 packet_put_cstring(strerror(err));
1346 packet_put_cstring("");
1347 }
1348 } else {
1349 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1350 packet_put_int(c->remote_id);
1351 }
1352 chan_mark_dead(c);
1353 }
1354 packet_send();
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001355 }
1356}
1357
Ben Lindstrombba81212001-06-25 05:01:22 +00001358static int
Damien Millerb38eff82000-04-01 11:09:21 +10001359channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset)
1360{
1361 char buf[16*1024];
1362 int len;
1363
Ben Lindstromc0dee1a2001-06-05 20:52:50 +00001364 if (c->rfd != -1 &&
Damien Millerb38eff82000-04-01 11:09:21 +10001365 FD_ISSET(c->rfd, readset)) {
1366 len = read(c->rfd, buf, sizeof(buf));
Damien Miller6f83b8e2000-05-02 09:23:45 +10001367 if (len < 0 && (errno == EINTR || errno == EAGAIN))
1368 return 1;
Damien Millerb38eff82000-04-01 11:09:21 +10001369 if (len <= 0) {
Damien Millerfbdeece2003-09-02 22:52:31 +10001370 debug2("channel %d: read<=0 rfd %d len %d",
Damien Millerb38eff82000-04-01 11:09:21 +10001371 c->self, c->rfd, len);
Ben Lindstromb3921512001-04-11 15:57:50 +00001372 if (c->type != SSH_CHANNEL_OPEN) {
Damien Millerfbdeece2003-09-02 22:52:31 +10001373 debug2("channel %d: not open", c->self);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001374 chan_mark_dead(c);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001375 return -1;
Ben Lindstromb3921512001-04-11 15:57:50 +00001376 } else if (compat13) {
Damien Miller76765c02002-01-22 23:21:15 +11001377 buffer_clear(&c->output);
Damien Millerb38eff82000-04-01 11:09:21 +10001378 c->type = SSH_CHANNEL_INPUT_DRAINING;
Damien Millerfbdeece2003-09-02 22:52:31 +10001379 debug2("channel %d: input draining.", c->self);
Damien Millerb38eff82000-04-01 11:09:21 +10001380 } else {
1381 chan_read_failed(c);
1382 }
1383 return -1;
1384 }
Ben Lindstrom1c37c6a2001-12-06 18:00:18 +00001385 if (c->input_filter != NULL) {
Damien Millerad833b32000-08-23 10:46:23 +10001386 if (c->input_filter(c, buf, len) == -1) {
Damien Millerfbdeece2003-09-02 22:52:31 +10001387 debug2("channel %d: filter stops", c->self);
Damien Millerad833b32000-08-23 10:46:23 +10001388 chan_read_failed(c);
1389 }
1390 } else {
1391 buffer_append(&c->input, buf, len);
1392 }
Damien Millerb38eff82000-04-01 11:09:21 +10001393 }
1394 return 1;
1395}
Ben Lindstrombba81212001-06-25 05:01:22 +00001396static int
Damien Millerb38eff82000-04-01 11:09:21 +10001397channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset)
1398{
Ben Lindstrome229b252001-03-05 06:28:06 +00001399 struct termios tio;
Ben Lindstrom6d218f42001-09-18 05:53:12 +00001400 u_char *data;
1401 u_int dlen;
Damien Millerb38eff82000-04-01 11:09:21 +10001402 int len;
1403
1404 /* Send buffered output data to the socket. */
Ben Lindstromc0dee1a2001-06-05 20:52:50 +00001405 if (c->wfd != -1 &&
Damien Millerb38eff82000-04-01 11:09:21 +10001406 FD_ISSET(c->wfd, writeset) &&
1407 buffer_len(&c->output) > 0) {
Ben Lindstrom6d218f42001-09-18 05:53:12 +00001408 data = buffer_ptr(&c->output);
1409 dlen = buffer_len(&c->output);
Ben Lindstrom92ea0ea2002-07-04 18:11:09 +00001410#ifdef _AIX
Damien Millera8e06ce2003-11-21 23:48:55 +11001411 /* XXX: Later AIX versions can't push as much data to tty */
Darren Tucker240fdfa2003-11-22 14:10:02 +11001412 if (compat20 && c->wfd_isatty)
1413 dlen = MIN(dlen, 8*1024);
Ben Lindstrom92ea0ea2002-07-04 18:11:09 +00001414#endif
Ben Lindstrombeb5f332002-07-22 15:28:53 +00001415 len = write(c->wfd, data, dlen);
Damien Miller6f83b8e2000-05-02 09:23:45 +10001416 if (len < 0 && (errno == EINTR || errno == EAGAIN))
1417 return 1;
Damien Millerb38eff82000-04-01 11:09:21 +10001418 if (len <= 0) {
Ben Lindstromb3921512001-04-11 15:57:50 +00001419 if (c->type != SSH_CHANNEL_OPEN) {
Damien Millerfbdeece2003-09-02 22:52:31 +10001420 debug2("channel %d: not open", c->self);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001421 chan_mark_dead(c);
Ben Lindstromb3921512001-04-11 15:57:50 +00001422 return -1;
1423 } else if (compat13) {
Damien Miller76765c02002-01-22 23:21:15 +11001424 buffer_clear(&c->output);
Damien Millerfbdeece2003-09-02 22:52:31 +10001425 debug2("channel %d: input draining.", c->self);
Damien Millerb38eff82000-04-01 11:09:21 +10001426 c->type = SSH_CHANNEL_INPUT_DRAINING;
1427 } else {
1428 chan_write_failed(c);
1429 }
1430 return -1;
1431 }
Ben Lindstrom6d218f42001-09-18 05:53:12 +00001432 if (compat20 && c->isatty && dlen >= 1 && data[0] != '\r') {
Damien Miller79438cc2001-02-16 12:34:57 +11001433 if (tcgetattr(c->wfd, &tio) == 0 &&
1434 !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1435 /*
1436 * Simulate echo to reduce the impact of
Ben Lindstromb40204b2001-03-05 06:29:44 +00001437 * traffic analysis. We need to match the
Ben Lindstrome229b252001-03-05 06:28:06 +00001438 * size of a SSH2_MSG_CHANNEL_DATA message
1439 * (4 byte channel id + data)
Damien Miller79438cc2001-02-16 12:34:57 +11001440 */
Ben Lindstrome229b252001-03-05 06:28:06 +00001441 packet_send_ignore(4 + len);
Damien Miller79438cc2001-02-16 12:34:57 +11001442 packet_send();
Damien Miller79438cc2001-02-16 12:34:57 +11001443 }
1444 }
Damien Millerb38eff82000-04-01 11:09:21 +10001445 buffer_consume(&c->output, len);
Damien Miller33b13562000-04-04 14:38:59 +10001446 if (compat20 && len > 0) {
1447 c->local_consumed += len;
1448 }
1449 }
1450 return 1;
1451}
Ben Lindstrombba81212001-06-25 05:01:22 +00001452static int
Damien Miller33b13562000-04-04 14:38:59 +10001453channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset)
1454{
1455 char buf[16*1024];
1456 int len;
1457
Damien Miller1383bd82000-04-06 12:32:37 +10001458/** XXX handle drain efd, too */
Damien Miller33b13562000-04-04 14:38:59 +10001459 if (c->efd != -1) {
1460 if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1461 FD_ISSET(c->efd, writeset) &&
1462 buffer_len(&c->extended) > 0) {
1463 len = write(c->efd, buffer_ptr(&c->extended),
1464 buffer_len(&c->extended));
Damien Millerd3444942000-09-30 14:20:03 +11001465 debug2("channel %d: written %d to efd %d",
Damien Miller33b13562000-04-04 14:38:59 +10001466 c->self, len, c->efd);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001467 if (len < 0 && (errno == EINTR || errno == EAGAIN))
1468 return 1;
1469 if (len <= 0) {
1470 debug2("channel %d: closing write-efd %d",
1471 c->self, c->efd);
Ben Lindstrom16d29d52001-07-18 16:01:46 +00001472 channel_close_fd(&c->efd);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001473 } else {
Damien Miller33b13562000-04-04 14:38:59 +10001474 buffer_consume(&c->extended, len);
1475 c->local_consumed += len;
1476 }
1477 } else if (c->extended_usage == CHAN_EXTENDED_READ &&
1478 FD_ISSET(c->efd, readset)) {
1479 len = read(c->efd, buf, sizeof(buf));
Damien Millerd3444942000-09-30 14:20:03 +11001480 debug2("channel %d: read %d from efd %d",
Damien Miller9f0f5c62001-12-21 14:45:46 +11001481 c->self, len, c->efd);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001482 if (len < 0 && (errno == EINTR || errno == EAGAIN))
1483 return 1;
1484 if (len <= 0) {
1485 debug2("channel %d: closing read-efd %d",
Damien Miller1383bd82000-04-06 12:32:37 +10001486 c->self, c->efd);
Ben Lindstrom16d29d52001-07-18 16:01:46 +00001487 channel_close_fd(&c->efd);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001488 } else {
Damien Miller33b13562000-04-04 14:38:59 +10001489 buffer_append(&c->extended, buf, len);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001490 }
Damien Miller33b13562000-04-04 14:38:59 +10001491 }
1492 }
1493 return 1;
1494}
Ben Lindstrombba81212001-06-25 05:01:22 +00001495static int
Damien Miller0e220db2004-06-15 10:34:08 +10001496channel_handle_ctl(Channel *c, fd_set * readset, fd_set * writeset)
1497{
1498 char buf[16];
1499 int len;
1500
1501 /* Monitor control fd to detect if the slave client exits */
1502 if (c->ctl_fd != -1 && FD_ISSET(c->ctl_fd, readset)) {
1503 len = read(c->ctl_fd, buf, sizeof(buf));
1504 if (len < 0 && (errno == EINTR || errno == EAGAIN))
1505 return 1;
1506 if (len <= 0) {
1507 debug2("channel %d: ctl read<=0", c->self);
1508 if (c->type != SSH_CHANNEL_OPEN) {
1509 debug2("channel %d: not open", c->self);
1510 chan_mark_dead(c);
1511 return -1;
1512 } else {
1513 chan_read_failed(c);
1514 chan_write_failed(c);
1515 }
1516 return -1;
1517 } else
1518 fatal("%s: unexpected data on ctl fd", __func__);
1519 }
1520 return 1;
1521}
1522static int
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001523channel_check_window(Channel *c)
Damien Miller33b13562000-04-04 14:38:59 +10001524{
Ben Lindstromb3921512001-04-11 15:57:50 +00001525 if (c->type == SSH_CHANNEL_OPEN &&
1526 !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
Damien Miller33b13562000-04-04 14:38:59 +10001527 c->local_window < c->local_window_max/2 &&
1528 c->local_consumed > 0) {
1529 packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1530 packet_put_int(c->remote_id);
1531 packet_put_int(c->local_consumed);
1532 packet_send();
Damien Millerd3444942000-09-30 14:20:03 +11001533 debug2("channel %d: window %d sent adjust %d",
Damien Miller33b13562000-04-04 14:38:59 +10001534 c->self, c->local_window,
1535 c->local_consumed);
1536 c->local_window += c->local_consumed;
1537 c->local_consumed = 0;
Damien Millerb38eff82000-04-01 11:09:21 +10001538 }
1539 return 1;
1540}
1541
Ben Lindstrombba81212001-06-25 05:01:22 +00001542static void
Damien Millerde6987c2002-01-22 23:20:40 +11001543channel_post_open(Channel *c, fd_set * readset, fd_set * writeset)
Damien Millerb38eff82000-04-01 11:09:21 +10001544{
Damien Miller4623a752001-10-10 15:03:58 +10001545 if (c->delayed)
1546 return;
Damien Millerb38eff82000-04-01 11:09:21 +10001547 channel_handle_rfd(c, readset, writeset);
1548 channel_handle_wfd(c, readset, writeset);
Damien Millerde6987c2002-01-22 23:20:40 +11001549 if (!compat20)
Damien Miller4623a752001-10-10 15:03:58 +10001550 return;
Damien Miller33b13562000-04-04 14:38:59 +10001551 channel_handle_efd(c, readset, writeset);
Damien Miller0e220db2004-06-15 10:34:08 +10001552 channel_handle_ctl(c, readset, writeset);
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001553 channel_check_window(c);
Damien Miller33b13562000-04-04 14:38:59 +10001554}
1555
Ben Lindstrombba81212001-06-25 05:01:22 +00001556static void
Damien Millerb38eff82000-04-01 11:09:21 +10001557channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset)
1558{
1559 int len;
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +00001560
Damien Millerb38eff82000-04-01 11:09:21 +10001561 /* Send buffered output data to the socket. */
1562 if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
1563 len = write(c->sock, buffer_ptr(&c->output),
1564 buffer_len(&c->output));
1565 if (len <= 0)
Damien Miller76765c02002-01-22 23:21:15 +11001566 buffer_clear(&c->output);
Damien Millerb38eff82000-04-01 11:09:21 +10001567 else
1568 buffer_consume(&c->output, len);
1569 }
1570}
1571
Ben Lindstrombba81212001-06-25 05:01:22 +00001572static void
Damien Miller33b13562000-04-04 14:38:59 +10001573channel_handler_init_20(void)
1574{
Damien Millerde6987c2002-01-22 23:20:40 +11001575 channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
Damien Millerbd483e72000-04-30 10:00:53 +10001576 channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
Damien Miller33b13562000-04-04 14:38:59 +10001577 channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
Damien Miller0bc1bd82000-11-13 22:57:25 +11001578 channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
Damien Millerbd483e72000-04-30 10:00:53 +10001579 channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
Damien Miller0bc1bd82000-11-13 22:57:25 +11001580 channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001581 channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001582 channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
Damien Miller33b13562000-04-04 14:38:59 +10001583
Damien Millerde6987c2002-01-22 23:20:40 +11001584 channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
Damien Miller33b13562000-04-04 14:38:59 +10001585 channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
Damien Miller0bc1bd82000-11-13 22:57:25 +11001586 channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
Damien Millerbd483e72000-04-30 10:00:53 +10001587 channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
Damien Miller0bc1bd82000-11-13 22:57:25 +11001588 channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001589 channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
Damien Millerde6987c2002-01-22 23:20:40 +11001590 channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
Damien Miller33b13562000-04-04 14:38:59 +10001591}
1592
Ben Lindstrombba81212001-06-25 05:01:22 +00001593static void
Damien Millerb38eff82000-04-01 11:09:21 +10001594channel_handler_init_13(void)
1595{
1596 channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
1597 channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
1598 channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1599 channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1600 channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1601 channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
1602 channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001603 channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001604 channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
Damien Millerb38eff82000-04-01 11:09:21 +10001605
Damien Millerde6987c2002-01-22 23:20:40 +11001606 channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
Damien Millerb38eff82000-04-01 11:09:21 +10001607 channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1608 channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1609 channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1610 channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001611 channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
Damien Millerde6987c2002-01-22 23:20:40 +11001612 channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
Damien Millerb38eff82000-04-01 11:09:21 +10001613}
1614
Ben Lindstrombba81212001-06-25 05:01:22 +00001615static void
Damien Millerb38eff82000-04-01 11:09:21 +10001616channel_handler_init_15(void)
1617{
Damien Millerde6987c2002-01-22 23:20:40 +11001618 channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
Damien Millerbd483e72000-04-30 10:00:53 +10001619 channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
Damien Millerb38eff82000-04-01 11:09:21 +10001620 channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1621 channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1622 channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001623 channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001624 channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
Damien Millerb38eff82000-04-01 11:09:21 +10001625
1626 channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1627 channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1628 channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
Damien Millerde6987c2002-01-22 23:20:40 +11001629 channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001630 channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
Damien Millerde6987c2002-01-22 23:20:40 +11001631 channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
Damien Millerb38eff82000-04-01 11:09:21 +10001632}
1633
Ben Lindstrombba81212001-06-25 05:01:22 +00001634static void
Damien Millerb38eff82000-04-01 11:09:21 +10001635channel_handler_init(void)
1636{
1637 int i;
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +00001638
Damien Miller9f0f5c62001-12-21 14:45:46 +11001639 for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
Damien Millerb38eff82000-04-01 11:09:21 +10001640 channel_pre[i] = NULL;
1641 channel_post[i] = NULL;
1642 }
Damien Miller33b13562000-04-04 14:38:59 +10001643 if (compat20)
1644 channel_handler_init_20();
1645 else if (compat13)
Damien Millerb38eff82000-04-01 11:09:21 +10001646 channel_handler_init_13();
1647 else
1648 channel_handler_init_15();
1649}
1650
Damien Miller3ec27592001-10-12 11:35:04 +10001651/* gc dead channels */
1652static void
1653channel_garbage_collect(Channel *c)
1654{
1655 if (c == NULL)
1656 return;
1657 if (c->detach_user != NULL) {
1658 if (!chan_is_dead(c, 0))
1659 return;
Damien Millerfbdeece2003-09-02 22:52:31 +10001660 debug2("channel %d: gc: notify user", c->self);
Damien Miller3ec27592001-10-12 11:35:04 +10001661 c->detach_user(c->self, NULL);
1662 /* if we still have a callback */
1663 if (c->detach_user != NULL)
1664 return;
Damien Millerfbdeece2003-09-02 22:52:31 +10001665 debug2("channel %d: gc: user detached", c->self);
Damien Miller3ec27592001-10-12 11:35:04 +10001666 }
1667 if (!chan_is_dead(c, 1))
1668 return;
Damien Millerfbdeece2003-09-02 22:52:31 +10001669 debug2("channel %d: garbage collecting", c->self);
Damien Miller3ec27592001-10-12 11:35:04 +10001670 channel_free(c);
1671}
1672
Ben Lindstrombba81212001-06-25 05:01:22 +00001673static void
Damien Millerb38eff82000-04-01 11:09:21 +10001674channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset)
1675{
1676 static int did_init = 0;
1677 int i;
1678 Channel *c;
1679
1680 if (!did_init) {
1681 channel_handler_init();
1682 did_init = 1;
1683 }
1684 for (i = 0; i < channels_alloc; i++) {
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001685 c = channels[i];
1686 if (c == NULL)
Damien Millerb38eff82000-04-01 11:09:21 +10001687 continue;
Ben Lindstromc0dee1a2001-06-05 20:52:50 +00001688 if (ftab[c->type] != NULL)
1689 (*ftab[c->type])(c, readset, writeset);
Damien Miller3ec27592001-10-12 11:35:04 +10001690 channel_garbage_collect(c);
Damien Millerb38eff82000-04-01 11:09:21 +10001691 }
1692}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001693
Ben Lindstrome9c99912001-06-09 00:41:05 +00001694/*
1695 * Allocate/update select bitmasks and add any bits relevant to channels in
1696 * select bitmasks.
1697 */
Damien Miller4af51302000-04-16 11:18:38 +10001698void
Ben Lindstrombe2cc432001-04-04 23:46:07 +00001699channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
Ben Lindstrom16d29d52001-07-18 16:01:46 +00001700 int *nallocp, int rekeying)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001701{
Damien Miller5e953212001-01-30 09:14:00 +11001702 int n;
1703 u_int sz;
1704
1705 n = MAX(*maxfdp, channel_max_fd);
1706
1707 sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
Ben Lindstrom16d29d52001-07-18 16:01:46 +00001708 /* perhaps check sz < nalloc/2 and shrink? */
1709 if (*readsetp == NULL || sz > *nallocp) {
1710 *readsetp = xrealloc(*readsetp, sz);
1711 *writesetp = xrealloc(*writesetp, sz);
1712 *nallocp = sz;
Damien Miller5e953212001-01-30 09:14:00 +11001713 }
Ben Lindstrom16d29d52001-07-18 16:01:46 +00001714 *maxfdp = n;
Damien Miller5e953212001-01-30 09:14:00 +11001715 memset(*readsetp, 0, sz);
1716 memset(*writesetp, 0, sz);
1717
Ben Lindstrombe2cc432001-04-04 23:46:07 +00001718 if (!rekeying)
1719 channel_handler(channel_pre, *readsetp, *writesetp);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001720}
1721
Ben Lindstrome9c99912001-06-09 00:41:05 +00001722/*
1723 * After select, perform any appropriate operations for channels which have
1724 * events pending.
1725 */
Damien Miller4af51302000-04-16 11:18:38 +10001726void
Damien Miller95def091999-11-25 00:26:21 +11001727channel_after_select(fd_set * readset, fd_set * writeset)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001728{
Damien Millerb38eff82000-04-01 11:09:21 +10001729 channel_handler(channel_post, readset, writeset);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001730}
1731
Ben Lindstrome9c99912001-06-09 00:41:05 +00001732
Damien Miller5e953212001-01-30 09:14:00 +11001733/* If there is data to send to the connection, enqueue some of it now. */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001734
Damien Miller4af51302000-04-16 11:18:38 +10001735void
Ben Lindstrom3c36bb22001-12-06 17:55:26 +00001736channel_output_poll(void)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001737{
Damien Millerb38eff82000-04-01 11:09:21 +10001738 Channel *c;
Ben Lindstrom4fed2be2002-06-25 23:17:36 +00001739 int i;
1740 u_int len;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001741
Damien Miller95def091999-11-25 00:26:21 +11001742 for (i = 0; i < channels_alloc; i++) {
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001743 c = channels[i];
1744 if (c == NULL)
1745 continue;
Damien Miller34132e52000-01-14 15:45:46 +11001746
Ben Lindstrome9c99912001-06-09 00:41:05 +00001747 /*
1748 * We are only interested in channels that can have buffered
1749 * incoming data.
1750 */
Damien Miller34132e52000-01-14 15:45:46 +11001751 if (compat13) {
Damien Millerb38eff82000-04-01 11:09:21 +10001752 if (c->type != SSH_CHANNEL_OPEN &&
1753 c->type != SSH_CHANNEL_INPUT_DRAINING)
Damien Miller34132e52000-01-14 15:45:46 +11001754 continue;
1755 } else {
Damien Millerb38eff82000-04-01 11:09:21 +10001756 if (c->type != SSH_CHANNEL_OPEN)
Damien Miller34132e52000-01-14 15:45:46 +11001757 continue;
Damien Miller34132e52000-01-14 15:45:46 +11001758 }
Damien Millerefb4afe2000-04-12 18:45:05 +10001759 if (compat20 &&
1760 (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001761 /* XXX is this true? */
Damien Miller3ec27592001-10-12 11:35:04 +10001762 debug3("channel %d: will not send data after close", c->self);
Damien Miller33b13562000-04-04 14:38:59 +10001763 continue;
1764 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001765
Damien Miller95def091999-11-25 00:26:21 +11001766 /* Get the amount of buffered data for this channel. */
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001767 if ((c->istate == CHAN_INPUT_OPEN ||
1768 c->istate == CHAN_INPUT_WAIT_DRAIN) &&
1769 (len = buffer_len(&c->input)) > 0) {
Ben Lindstrome9c99912001-06-09 00:41:05 +00001770 /*
1771 * Send some data for the other side over the secure
1772 * connection.
1773 */
Damien Miller33b13562000-04-04 14:38:59 +10001774 if (compat20) {
1775 if (len > c->remote_window)
1776 len = c->remote_window;
1777 if (len > c->remote_maxpacket)
1778 len = c->remote_maxpacket;
Damien Miller95def091999-11-25 00:26:21 +11001779 } else {
Damien Miller33b13562000-04-04 14:38:59 +10001780 if (packet_is_interactive()) {
1781 if (len > 1024)
1782 len = 512;
1783 } else {
1784 /* Keep the packets at reasonable size. */
1785 if (len > packet_get_maxsize()/2)
1786 len = packet_get_maxsize()/2;
1787 }
Damien Miller95def091999-11-25 00:26:21 +11001788 }
Damien Millerb38eff82000-04-01 11:09:21 +10001789 if (len > 0) {
Damien Miller33b13562000-04-04 14:38:59 +10001790 packet_start(compat20 ?
1791 SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
Damien Millerb38eff82000-04-01 11:09:21 +10001792 packet_put_int(c->remote_id);
1793 packet_put_string(buffer_ptr(&c->input), len);
1794 packet_send();
1795 buffer_consume(&c->input, len);
1796 c->remote_window -= len;
Damien Millerb38eff82000-04-01 11:09:21 +10001797 }
1798 } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
Damien Miller95def091999-11-25 00:26:21 +11001799 if (compat13)
1800 fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
Damien Miller5428f641999-11-25 11:54:57 +11001801 /*
1802 * input-buffer is empty and read-socket shutdown:
Ben Lindstromcf159442002-03-26 03:26:24 +00001803 * tell peer, that we will not send more data: send IEOF.
1804 * hack for extended data: delay EOF if EFD still in use.
Damien Miller5428f641999-11-25 11:54:57 +11001805 */
Ben Lindstromcf159442002-03-26 03:26:24 +00001806 if (CHANNEL_EFD_INPUT_ACTIVE(c))
Ben Lindstrom5a6abda2002-06-09 19:41:48 +00001807 debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
1808 c->self, c->efd, buffer_len(&c->extended));
Ben Lindstromcf159442002-03-26 03:26:24 +00001809 else
1810 chan_ibuf_empty(c);
Damien Miller95def091999-11-25 00:26:21 +11001811 }
Damien Miller33b13562000-04-04 14:38:59 +10001812 /* Send extended data, i.e. stderr */
1813 if (compat20 &&
Ben Lindstromcf159442002-03-26 03:26:24 +00001814 !(c->flags & CHAN_EOF_SENT) &&
Damien Miller33b13562000-04-04 14:38:59 +10001815 c->remote_window > 0 &&
1816 (len = buffer_len(&c->extended)) > 0 &&
1817 c->extended_usage == CHAN_EXTENDED_READ) {
Ben Lindstrom4fed2be2002-06-25 23:17:36 +00001818 debug2("channel %d: rwin %u elen %u euse %d",
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001819 c->self, c->remote_window, buffer_len(&c->extended),
1820 c->extended_usage);
Damien Miller33b13562000-04-04 14:38:59 +10001821 if (len > c->remote_window)
1822 len = c->remote_window;
1823 if (len > c->remote_maxpacket)
1824 len = c->remote_maxpacket;
1825 packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
1826 packet_put_int(c->remote_id);
1827 packet_put_int(SSH2_EXTENDED_DATA_STDERR);
1828 packet_put_string(buffer_ptr(&c->extended), len);
1829 packet_send();
1830 buffer_consume(&c->extended, len);
1831 c->remote_window -= len;
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00001832 debug2("channel %d: sent ext data %d", c->self, len);
Damien Miller33b13562000-04-04 14:38:59 +10001833 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001834 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001835}
1836
Ben Lindstrome9c99912001-06-09 00:41:05 +00001837
1838/* -- protocol input */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001839
Damien Miller4af51302000-04-16 11:18:38 +10001840void
Damien Miller630d6f42002-01-22 23:17:30 +11001841channel_input_data(int type, u_int32_t seq, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001842{
Damien Miller34132e52000-01-14 15:45:46 +11001843 int id;
Damien Miller95def091999-11-25 00:26:21 +11001844 char *data;
Ben Lindstrom46c16222000-12-22 01:43:59 +00001845 u_int data_len;
Damien Millerb38eff82000-04-01 11:09:21 +10001846 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001847
Damien Miller95def091999-11-25 00:26:21 +11001848 /* Get the channel number and verify it. */
Damien Miller34132e52000-01-14 15:45:46 +11001849 id = packet_get_int();
Damien Millerb38eff82000-04-01 11:09:21 +10001850 c = channel_lookup(id);
1851 if (c == NULL)
Damien Miller34132e52000-01-14 15:45:46 +11001852 packet_disconnect("Received data for nonexistent channel %d.", id);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001853
Damien Miller95def091999-11-25 00:26:21 +11001854 /* Ignore any data for non-open channels (might happen on close) */
Damien Millerb38eff82000-04-01 11:09:21 +10001855 if (c->type != SSH_CHANNEL_OPEN &&
1856 c->type != SSH_CHANNEL_X11_OPEN)
Damien Miller34132e52000-01-14 15:45:46 +11001857 return;
1858
Damien Miller95def091999-11-25 00:26:21 +11001859 /* Get the data. */
1860 data = packet_get_string(&data_len);
Damien Millerb38eff82000-04-01 11:09:21 +10001861
Damien Millera04ad492004-01-21 11:02:09 +11001862 /*
1863 * Ignore data for protocol > 1.3 if output end is no longer open.
1864 * For protocol 2 the sending side is reducing its window as it sends
1865 * data, so we must 'fake' consumption of the data in order to ensure
1866 * that window updates are sent back. Otherwise the connection might
1867 * deadlock.
1868 */
1869 if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) {
1870 if (compat20) {
1871 c->local_window -= data_len;
1872 c->local_consumed += data_len;
1873 }
1874 xfree(data);
1875 return;
1876 }
1877
Ben Lindstrom1c37c6a2001-12-06 18:00:18 +00001878 if (compat20) {
Damien Miller33b13562000-04-04 14:38:59 +10001879 if (data_len > c->local_maxpacket) {
Damien Miller996acd22003-04-09 20:59:48 +10001880 logit("channel %d: rcvd big packet %d, maxpack %d",
Damien Miller33b13562000-04-04 14:38:59 +10001881 c->self, data_len, c->local_maxpacket);
1882 }
1883 if (data_len > c->local_window) {
Damien Miller996acd22003-04-09 20:59:48 +10001884 logit("channel %d: rcvd too much data %d, win %d",
Damien Miller33b13562000-04-04 14:38:59 +10001885 c->self, data_len, c->local_window);
1886 xfree(data);
1887 return;
1888 }
1889 c->local_window -= data_len;
Damien Miller33b13562000-04-04 14:38:59 +10001890 }
Damien Miller48b03fc2002-01-22 23:11:40 +11001891 packet_check_eom();
Damien Millerb38eff82000-04-01 11:09:21 +10001892 buffer_append(&c->output, data, data_len);
Damien Miller95def091999-11-25 00:26:21 +11001893 xfree(data);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001894}
Ben Lindstrome9c99912001-06-09 00:41:05 +00001895
Damien Miller4af51302000-04-16 11:18:38 +10001896void
Damien Miller630d6f42002-01-22 23:17:30 +11001897channel_input_extended_data(int type, u_int32_t seq, void *ctxt)
Damien Miller33b13562000-04-04 14:38:59 +10001898{
1899 int id;
Damien Miller33b13562000-04-04 14:38:59 +10001900 char *data;
Ben Lindstromdaa21792002-06-25 23:15:30 +00001901 u_int data_len, tcode;
Damien Miller33b13562000-04-04 14:38:59 +10001902 Channel *c;
1903
1904 /* Get the channel number and verify it. */
1905 id = packet_get_int();
1906 c = channel_lookup(id);
1907
1908 if (c == NULL)
1909 packet_disconnect("Received extended_data for bad channel %d.", id);
1910 if (c->type != SSH_CHANNEL_OPEN) {
Damien Miller996acd22003-04-09 20:59:48 +10001911 logit("channel %d: ext data for non open", id);
Damien Miller33b13562000-04-04 14:38:59 +10001912 return;
1913 }
Ben Lindstromcf159442002-03-26 03:26:24 +00001914 if (c->flags & CHAN_EOF_RCVD) {
1915 if (datafellows & SSH_BUG_EXTEOF)
1916 debug("channel %d: accepting ext data after eof", id);
1917 else
1918 packet_disconnect("Received extended_data after EOF "
1919 "on channel %d.", id);
1920 }
Damien Miller33b13562000-04-04 14:38:59 +10001921 tcode = packet_get_int();
1922 if (c->efd == -1 ||
1923 c->extended_usage != CHAN_EXTENDED_WRITE ||
1924 tcode != SSH2_EXTENDED_DATA_STDERR) {
Damien Miller996acd22003-04-09 20:59:48 +10001925 logit("channel %d: bad ext data", c->self);
Damien Miller33b13562000-04-04 14:38:59 +10001926 return;
1927 }
1928 data = packet_get_string(&data_len);
Damien Miller48b03fc2002-01-22 23:11:40 +11001929 packet_check_eom();
Damien Miller33b13562000-04-04 14:38:59 +10001930 if (data_len > c->local_window) {
Damien Miller996acd22003-04-09 20:59:48 +10001931 logit("channel %d: rcvd too much extended_data %d, win %d",
Damien Miller33b13562000-04-04 14:38:59 +10001932 c->self, data_len, c->local_window);
1933 xfree(data);
1934 return;
1935 }
Damien Millerd3444942000-09-30 14:20:03 +11001936 debug2("channel %d: rcvd ext data %d", c->self, data_len);
Damien Miller33b13562000-04-04 14:38:59 +10001937 c->local_window -= data_len;
1938 buffer_append(&c->extended, data, data_len);
1939 xfree(data);
1940}
1941
Damien Miller4af51302000-04-16 11:18:38 +10001942void
Damien Miller630d6f42002-01-22 23:17:30 +11001943channel_input_ieof(int type, u_int32_t seq, void *ctxt)
Damien Millerb38eff82000-04-01 11:09:21 +10001944{
1945 int id;
1946 Channel *c;
1947
Damien Millerb38eff82000-04-01 11:09:21 +10001948 id = packet_get_int();
Damien Miller48b03fc2002-01-22 23:11:40 +11001949 packet_check_eom();
Damien Millerb38eff82000-04-01 11:09:21 +10001950 c = channel_lookup(id);
1951 if (c == NULL)
1952 packet_disconnect("Received ieof for nonexistent channel %d.", id);
1953 chan_rcvd_ieof(c);
Ben Lindstrom944c4f02001-09-18 05:51:13 +00001954
1955 /* XXX force input close */
Damien Millera90fc082002-01-22 23:19:38 +11001956 if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
Ben Lindstrom944c4f02001-09-18 05:51:13 +00001957 debug("channel %d: FORCE input drain", c->self);
1958 c->istate = CHAN_INPUT_WAIT_DRAIN;
Damien Miller73f10742002-01-22 23:34:52 +11001959 if (buffer_len(&c->input) == 0)
1960 chan_ibuf_empty(c);
Ben Lindstrom944c4f02001-09-18 05:51:13 +00001961 }
1962
Damien Millerb38eff82000-04-01 11:09:21 +10001963}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001964
Damien Miller4af51302000-04-16 11:18:38 +10001965void
Damien Miller630d6f42002-01-22 23:17:30 +11001966channel_input_close(int type, u_int32_t seq, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001967{
Damien Millerb38eff82000-04-01 11:09:21 +10001968 int id;
1969 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001970
Damien Millerb38eff82000-04-01 11:09:21 +10001971 id = packet_get_int();
Damien Miller48b03fc2002-01-22 23:11:40 +11001972 packet_check_eom();
Damien Millerb38eff82000-04-01 11:09:21 +10001973 c = channel_lookup(id);
1974 if (c == NULL)
1975 packet_disconnect("Received close for nonexistent channel %d.", id);
Damien Miller5428f641999-11-25 11:54:57 +11001976
1977 /*
1978 * Send a confirmation that we have closed the channel and no more
1979 * data is coming for it.
1980 */
Damien Miller95def091999-11-25 00:26:21 +11001981 packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
Damien Millerb38eff82000-04-01 11:09:21 +10001982 packet_put_int(c->remote_id);
Damien Miller95def091999-11-25 00:26:21 +11001983 packet_send();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001984
Damien Miller5428f641999-11-25 11:54:57 +11001985 /*
1986 * If the channel is in closed state, we have sent a close request,
1987 * and the other side will eventually respond with a confirmation.
1988 * Thus, we cannot free the channel here, because then there would be
1989 * no-one to receive the confirmation. The channel gets freed when
1990 * the confirmation arrives.
1991 */
Damien Millerb38eff82000-04-01 11:09:21 +10001992 if (c->type != SSH_CHANNEL_CLOSED) {
Damien Miller5428f641999-11-25 11:54:57 +11001993 /*
1994 * Not a closed channel - mark it as draining, which will
1995 * cause it to be freed later.
1996 */
Damien Miller76765c02002-01-22 23:21:15 +11001997 buffer_clear(&c->input);
Damien Millerb38eff82000-04-01 11:09:21 +10001998 c->type = SSH_CHANNEL_OUTPUT_DRAINING;
Damien Miller95def091999-11-25 00:26:21 +11001999 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002000}
2001
Damien Millerb38eff82000-04-01 11:09:21 +10002002/* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
Damien Miller4af51302000-04-16 11:18:38 +10002003void
Damien Miller630d6f42002-01-22 23:17:30 +11002004channel_input_oclose(int type, u_int32_t seq, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002005{
Damien Millerb38eff82000-04-01 11:09:21 +10002006 int id = packet_get_int();
2007 Channel *c = channel_lookup(id);
Damien Miller66823cd2002-01-22 23:11:38 +11002008
Damien Miller48b03fc2002-01-22 23:11:40 +11002009 packet_check_eom();
Damien Millerb38eff82000-04-01 11:09:21 +10002010 if (c == NULL)
2011 packet_disconnect("Received oclose for nonexistent channel %d.", id);
2012 chan_rcvd_oclose(c);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002013}
2014
Damien Miller4af51302000-04-16 11:18:38 +10002015void
Damien Miller630d6f42002-01-22 23:17:30 +11002016channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt)
Damien Millerb38eff82000-04-01 11:09:21 +10002017{
2018 int id = packet_get_int();
2019 Channel *c = channel_lookup(id);
2020
Damien Miller48b03fc2002-01-22 23:11:40 +11002021 packet_check_eom();
Damien Millerb38eff82000-04-01 11:09:21 +10002022 if (c == NULL)
2023 packet_disconnect("Received close confirmation for "
2024 "out-of-range channel %d.", id);
2025 if (c->type != SSH_CHANNEL_CLOSED)
2026 packet_disconnect("Received close confirmation for "
2027 "non-closed channel %d (type %d).", id, c->type);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002028 channel_free(c);
Damien Millerb38eff82000-04-01 11:09:21 +10002029}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002030
Damien Miller4af51302000-04-16 11:18:38 +10002031void
Damien Miller630d6f42002-01-22 23:17:30 +11002032channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002033{
Damien Millerb38eff82000-04-01 11:09:21 +10002034 int id, remote_id;
2035 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002036
Damien Millerb38eff82000-04-01 11:09:21 +10002037 id = packet_get_int();
2038 c = channel_lookup(id);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002039
Damien Millerb38eff82000-04-01 11:09:21 +10002040 if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2041 packet_disconnect("Received open confirmation for "
2042 "non-opening channel %d.", id);
2043 remote_id = packet_get_int();
Damien Miller5428f641999-11-25 11:54:57 +11002044 /* Record the remote channel number and mark that the channel is now open. */
Damien Millerb38eff82000-04-01 11:09:21 +10002045 c->remote_id = remote_id;
2046 c->type = SSH_CHANNEL_OPEN;
Damien Miller33b13562000-04-04 14:38:59 +10002047
2048 if (compat20) {
2049 c->remote_window = packet_get_int();
2050 c->remote_maxpacket = packet_get_int();
Damien Miller67f0bc02002-02-05 12:23:08 +11002051 if (c->confirm) {
Damien Millerd3444942000-09-30 14:20:03 +11002052 debug2("callback start");
Damien Miller0e220db2004-06-15 10:34:08 +10002053 c->confirm(c->self, c->confirm_ctx);
Damien Millerd3444942000-09-30 14:20:03 +11002054 debug2("callback done");
Damien Miller33b13562000-04-04 14:38:59 +10002055 }
Damien Millerfbdeece2003-09-02 22:52:31 +10002056 debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
Damien Miller33b13562000-04-04 14:38:59 +10002057 c->remote_window, c->remote_maxpacket);
2058 }
Damien Miller48b03fc2002-01-22 23:11:40 +11002059 packet_check_eom();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002060}
2061
Ben Lindstrombba81212001-06-25 05:01:22 +00002062static char *
Ben Lindstrom69128662001-05-08 20:07:39 +00002063reason2txt(int reason)
2064{
Ben Lindstrom1c37c6a2001-12-06 18:00:18 +00002065 switch (reason) {
Ben Lindstrom69128662001-05-08 20:07:39 +00002066 case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
2067 return "administratively prohibited";
2068 case SSH2_OPEN_CONNECT_FAILED:
2069 return "connect failed";
2070 case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
2071 return "unknown channel type";
2072 case SSH2_OPEN_RESOURCE_SHORTAGE:
2073 return "resource shortage";
2074 }
Ben Lindstrome2595442001-06-05 20:01:39 +00002075 return "unknown reason";
Ben Lindstrom69128662001-05-08 20:07:39 +00002076}
2077
Damien Miller4af51302000-04-16 11:18:38 +10002078void
Damien Miller630d6f42002-01-22 23:17:30 +11002079channel_input_open_failure(int type, u_int32_t seq, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002080{
Kevin Steves12057502001-02-05 14:54:34 +00002081 int id, reason;
2082 char *msg = NULL, *lang = NULL;
Damien Millerb38eff82000-04-01 11:09:21 +10002083 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002084
Damien Millerb38eff82000-04-01 11:09:21 +10002085 id = packet_get_int();
2086 c = channel_lookup(id);
2087
2088 if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2089 packet_disconnect("Received open failure for "
2090 "non-opening channel %d.", id);
Damien Miller33b13562000-04-04 14:38:59 +10002091 if (compat20) {
Kevin Steves12057502001-02-05 14:54:34 +00002092 reason = packet_get_int();
Ben Lindstromf3436742001-04-29 19:52:00 +00002093 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
Kevin Steves12057502001-02-05 14:54:34 +00002094 msg = packet_get_string(NULL);
2095 lang = packet_get_string(NULL);
2096 }
Damien Miller996acd22003-04-09 20:59:48 +10002097 logit("channel %d: open failed: %s%s%s", id,
Ben Lindstrom69128662001-05-08 20:07:39 +00002098 reason2txt(reason), msg ? ": ": "", msg ? msg : "");
Kevin Steves12057502001-02-05 14:54:34 +00002099 if (msg != NULL)
2100 xfree(msg);
2101 if (lang != NULL)
2102 xfree(lang);
Damien Miller33b13562000-04-04 14:38:59 +10002103 }
Damien Miller48b03fc2002-01-22 23:11:40 +11002104 packet_check_eom();
Damien Miller95def091999-11-25 00:26:21 +11002105 /* Free the channel. This will also close the socket. */
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002106 channel_free(c);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002107}
2108
Damien Miller33b13562000-04-04 14:38:59 +10002109void
Damien Miller630d6f42002-01-22 23:17:30 +11002110channel_input_window_adjust(int type, u_int32_t seq, void *ctxt)
Damien Miller33b13562000-04-04 14:38:59 +10002111{
2112 Channel *c;
Ben Lindstrom4fed2be2002-06-25 23:17:36 +00002113 int id;
2114 u_int adjust;
Damien Miller33b13562000-04-04 14:38:59 +10002115
2116 if (!compat20)
2117 return;
2118
2119 /* Get the channel number and verify it. */
2120 id = packet_get_int();
2121 c = channel_lookup(id);
2122
2123 if (c == NULL || c->type != SSH_CHANNEL_OPEN) {
Damien Miller996acd22003-04-09 20:59:48 +10002124 logit("Received window adjust for "
Damien Miller33b13562000-04-04 14:38:59 +10002125 "non-open channel %d.", id);
2126 return;
2127 }
2128 adjust = packet_get_int();
Damien Miller48b03fc2002-01-22 23:11:40 +11002129 packet_check_eom();
Ben Lindstrom4fed2be2002-06-25 23:17:36 +00002130 debug2("channel %d: rcvd adjust %u", id, adjust);
Damien Miller33b13562000-04-04 14:38:59 +10002131 c->remote_window += adjust;
2132}
2133
Damien Miller4af51302000-04-16 11:18:38 +10002134void
Damien Miller630d6f42002-01-22 23:17:30 +11002135channel_input_port_open(int type, u_int32_t seq, void *ctxt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002136{
Ben Lindstrome9c99912001-06-09 00:41:05 +00002137 Channel *c = NULL;
2138 u_short host_port;
2139 char *host, *originator_string;
2140 int remote_id, sock = -1;
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002141
Ben Lindstrome9c99912001-06-09 00:41:05 +00002142 remote_id = packet_get_int();
2143 host = packet_get_string(NULL);
2144 host_port = packet_get_int();
2145
2146 if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
2147 originator_string = packet_get_string(NULL);
2148 } else {
2149 originator_string = xstrdup("unknown (remote did not supply name)");
2150 }
Damien Miller48b03fc2002-01-22 23:11:40 +11002151 packet_check_eom();
Ben Lindstrome9c99912001-06-09 00:41:05 +00002152 sock = channel_connect_to(host, host_port);
2153 if (sock != -1) {
2154 c = channel_new("connected socket",
2155 SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0,
2156 originator_string, 1);
Damien Miller699d0032002-02-08 22:07:16 +11002157 c->remote_id = remote_id;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002158 }
Damien Millerb1ca8bb2003-05-14 13:45:42 +10002159 xfree(originator_string);
Ben Lindstrome9c99912001-06-09 00:41:05 +00002160 if (c == NULL) {
2161 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2162 packet_put_int(remote_id);
2163 packet_send();
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002164 }
Ben Lindstrome9c99912001-06-09 00:41:05 +00002165 xfree(host);
Ben Lindstrom5744dc42001-04-13 23:28:01 +00002166}
2167
2168
Ben Lindstrome9c99912001-06-09 00:41:05 +00002169/* -- tcp forwarding */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002170
Ben Lindstrom908afed2001-10-03 17:34:59 +00002171void
2172channel_set_af(int af)
2173{
2174 IPv4or6 = af;
2175}
2176
Damien Millerb16461c2002-01-22 23:29:22 +11002177static int
2178channel_setup_fwd_listener(int type, const char *listen_addr, u_short listen_port,
2179 const char *host_to_connect, u_short port_to_connect, int gateway_ports)
Damien Miller0bc1bd82000-11-13 22:57:25 +11002180{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002181 Channel *c;
Damien Millerb16461c2002-01-22 23:29:22 +11002182 int success, sock, on = 1;
Damien Miller34132e52000-01-14 15:45:46 +11002183 struct addrinfo hints, *ai, *aitop;
Damien Miller0bc1bd82000-11-13 22:57:25 +11002184 const char *host;
Damien Millerb16461c2002-01-22 23:29:22 +11002185 char ntop[NI_MAXHOST], strport[NI_MAXSERV];
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002186
Kevin Steves12057502001-02-05 14:54:34 +00002187 success = 0;
Damien Millerb16461c2002-01-22 23:29:22 +11002188 host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
2189 listen_addr : host_to_connect;
Kevin Steves12057502001-02-05 14:54:34 +00002190
Damien Millerb16461c2002-01-22 23:29:22 +11002191 if (host == NULL) {
2192 error("No forward host name.");
2193 return success;
Damien Miller0bc1bd82000-11-13 22:57:25 +11002194 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002195 if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) {
Kevin Steves12057502001-02-05 14:54:34 +00002196 error("Forward host name too long.");
2197 return success;
2198 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002199
Damien Miller5428f641999-11-25 11:54:57 +11002200 /*
Damien Miller34132e52000-01-14 15:45:46 +11002201 * getaddrinfo returns a loopback address if the hostname is
2202 * set to NULL and hints.ai_flags is not AI_PASSIVE
Damien Miller5428f641999-11-25 11:54:57 +11002203 */
Damien Miller34132e52000-01-14 15:45:46 +11002204 memset(&hints, 0, sizeof(hints));
2205 hints.ai_family = IPv4or6;
2206 hints.ai_flags = gateway_ports ? AI_PASSIVE : 0;
2207 hints.ai_socktype = SOCK_STREAM;
Damien Miller0bc1bd82000-11-13 22:57:25 +11002208 snprintf(strport, sizeof strport, "%d", listen_port);
Damien Miller34132e52000-01-14 15:45:46 +11002209 if (getaddrinfo(NULL, strport, &hints, &aitop) != 0)
2210 packet_disconnect("getaddrinfo: fatal error");
Damien Miller5428f641999-11-25 11:54:57 +11002211
Damien Miller34132e52000-01-14 15:45:46 +11002212 for (ai = aitop; ai; ai = ai->ai_next) {
2213 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2214 continue;
2215 if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2216 strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
Damien Millerb16461c2002-01-22 23:29:22 +11002217 error("channel_setup_fwd_listener: getnameinfo failed");
Damien Miller34132e52000-01-14 15:45:46 +11002218 continue;
2219 }
2220 /* Create a port to listen for the host. */
Damien Miller2372ace2003-05-14 13:42:23 +10002221 sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
Damien Miller34132e52000-01-14 15:45:46 +11002222 if (sock < 0) {
2223 /* this is no error since kernel may not support ipv6 */
2224 verbose("socket: %.100s", strerror(errno));
2225 continue;
2226 }
2227 /*
Damien Millere1383ce2002-09-19 11:49:37 +10002228 * Set socket options.
2229 * Allow local port reuse in TIME_WAIT.
Damien Miller34132e52000-01-14 15:45:46 +11002230 */
Damien Millere1383ce2002-09-19 11:49:37 +10002231 if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &on,
2232 sizeof(on)) == -1)
2233 error("setsockopt SO_REUSEADDR: %s", strerror(errno));
2234
Damien Miller34132e52000-01-14 15:45:46 +11002235 debug("Local forwarding listening on %s port %s.", ntop, strport);
Damien Miller95def091999-11-25 00:26:21 +11002236
Damien Miller34132e52000-01-14 15:45:46 +11002237 /* Bind the socket to the address. */
2238 if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2239 /* address can be in use ipv6 address is already bound */
Damien Miller3c7eeb22000-03-03 22:35:33 +11002240 if (!ai->ai_next)
2241 error("bind: %.100s", strerror(errno));
2242 else
2243 verbose("bind: %.100s", strerror(errno));
Kevin Stevesef4eea92001-02-05 12:42:17 +00002244
Damien Miller34132e52000-01-14 15:45:46 +11002245 close(sock);
2246 continue;
2247 }
2248 /* Start listening for connections on the socket. */
Darren Tucker3175eb92003-12-09 19:15:11 +11002249 if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
Damien Miller34132e52000-01-14 15:45:46 +11002250 error("listen: %.100s", strerror(errno));
2251 close(sock);
2252 continue;
2253 }
2254 /* Allocate a channel number for the socket. */
Ben Lindstrome9c99912001-06-09 00:41:05 +00002255 c = channel_new("port listener", type, sock, sock, -1,
Damien Millerbd483e72000-04-30 10:00:53 +10002256 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
Damien Millerb1ca8bb2003-05-14 13:45:42 +10002257 0, "port listener", 1);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002258 strlcpy(c->path, host, sizeof(c->path));
2259 c->host_port = port_to_connect;
2260 c->listening_port = listen_port;
Damien Miller34132e52000-01-14 15:45:46 +11002261 success = 1;
2262 }
2263 if (success == 0)
Damien Millerb16461c2002-01-22 23:29:22 +11002264 error("channel_setup_fwd_listener: cannot listen to port: %d",
Kevin Steves12057502001-02-05 14:54:34 +00002265 listen_port);
Damien Miller34132e52000-01-14 15:45:46 +11002266 freeaddrinfo(aitop);
Kevin Steves12057502001-02-05 14:54:34 +00002267 return success;
Damien Miller95def091999-11-25 00:26:21 +11002268}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002269
Darren Tuckere7066df2004-05-24 10:18:05 +10002270int
2271channel_cancel_rport_listener(const char *host, u_short port)
2272{
2273 int i, found = 0;
2274
2275 for(i = 0; i < channels_alloc; i++) {
2276 Channel *c = channels[i];
2277
2278 if (c != NULL && c->type == SSH_CHANNEL_RPORT_LISTENER &&
2279 strncmp(c->path, host, sizeof(c->path)) == 0 &&
2280 c->listening_port == port) {
2281 debug2("%s: close clannel %d", __func__, i);
2282 channel_free(c);
2283 found = 1;
2284 }
2285 }
2286
2287 return (found);
2288}
2289
Damien Millerb16461c2002-01-22 23:29:22 +11002290/* protocol local port fwd, used by ssh (and sshd in v1) */
2291int
2292channel_setup_local_fwd_listener(u_short listen_port,
2293 const char *host_to_connect, u_short port_to_connect, int gateway_ports)
2294{
2295 return channel_setup_fwd_listener(SSH_CHANNEL_PORT_LISTENER,
2296 NULL, listen_port, host_to_connect, port_to_connect, gateway_ports);
2297}
2298
2299/* protocol v2 remote port fwd, used by sshd */
2300int
2301channel_setup_remote_fwd_listener(const char *listen_address,
2302 u_short listen_port, int gateway_ports)
2303{
2304 return channel_setup_fwd_listener(SSH_CHANNEL_RPORT_LISTENER,
2305 listen_address, listen_port, NULL, 0, gateway_ports);
2306}
2307
Damien Miller5428f641999-11-25 11:54:57 +11002308/*
2309 * Initiate forwarding of connections to port "port" on remote host through
2310 * the secure channel to host:port from local side.
2311 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002312
Damien Miller4af51302000-04-16 11:18:38 +10002313void
Damien Miller0bc1bd82000-11-13 22:57:25 +11002314channel_request_remote_forwarding(u_short listen_port,
2315 const char *host_to_connect, u_short port_to_connect)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002316{
Damien Millerdff50992002-01-22 23:16:32 +11002317 int type, success = 0;
Damien Miller0bc1bd82000-11-13 22:57:25 +11002318
Damien Miller95def091999-11-25 00:26:21 +11002319 /* Record locally that connection to this host/port is permitted. */
2320 if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2321 fatal("channel_request_remote_forwarding: too many forwards");
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002322
Damien Miller95def091999-11-25 00:26:21 +11002323 /* Send the forward request to the remote side. */
Damien Miller33b13562000-04-04 14:38:59 +10002324 if (compat20) {
2325 const char *address_to_bind = "0.0.0.0";
2326 packet_start(SSH2_MSG_GLOBAL_REQUEST);
2327 packet_put_cstring("tcpip-forward");
Damien Miller2797f7f2002-04-23 21:09:44 +10002328 packet_put_char(1); /* boolean: want reply */
Damien Miller33b13562000-04-04 14:38:59 +10002329 packet_put_cstring(address_to_bind);
2330 packet_put_int(listen_port);
Damien Miller0bc1bd82000-11-13 22:57:25 +11002331 packet_send();
2332 packet_write_wait();
2333 /* Assume that server accepts the request */
2334 success = 1;
Damien Miller33b13562000-04-04 14:38:59 +10002335 } else {
2336 packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
Damien Miller33b13562000-04-04 14:38:59 +10002337 packet_put_int(listen_port);
Damien Miller8bb73be2000-04-19 16:26:12 +10002338 packet_put_cstring(host_to_connect);
2339 packet_put_int(port_to_connect);
Damien Miller33b13562000-04-04 14:38:59 +10002340 packet_send();
2341 packet_write_wait();
Damien Miller0bc1bd82000-11-13 22:57:25 +11002342
2343 /* Wait for response from the remote side. */
Damien Millerdff50992002-01-22 23:16:32 +11002344 type = packet_read();
Damien Miller0bc1bd82000-11-13 22:57:25 +11002345 switch (type) {
2346 case SSH_SMSG_SUCCESS:
2347 success = 1;
2348 break;
2349 case SSH_SMSG_FAILURE:
Damien Miller996acd22003-04-09 20:59:48 +10002350 logit("Warning: Server denied remote port forwarding.");
Damien Miller0bc1bd82000-11-13 22:57:25 +11002351 break;
2352 default:
2353 /* Unknown packet */
2354 packet_disconnect("Protocol error for port forward request:"
2355 "received packet type %d.", type);
2356 }
2357 }
2358 if (success) {
2359 permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
2360 permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
2361 permitted_opens[num_permitted_opens].listen_port = listen_port;
2362 num_permitted_opens++;
Damien Miller33b13562000-04-04 14:38:59 +10002363 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002364}
2365
Damien Miller5428f641999-11-25 11:54:57 +11002366/*
Darren Tuckere7066df2004-05-24 10:18:05 +10002367 * Request cancellation of remote forwarding of connection host:port from
2368 * local side.
2369 */
2370
2371void
2372channel_request_rforward_cancel(u_short port)
2373{
2374 int i;
2375 const char *address_to_bind = "0.0.0.0";
2376
2377 if (!compat20)
2378 return;
2379
2380 for (i = 0; i < num_permitted_opens; i++) {
2381 if (permitted_opens[i].host_to_connect != NULL &&
2382 permitted_opens[i].listen_port == port)
2383 break;
2384 }
2385 if (i >= num_permitted_opens) {
2386 debug("%s: requested forward not found", __func__);
2387 return;
2388 }
2389 packet_start(SSH2_MSG_GLOBAL_REQUEST);
2390 packet_put_cstring("cancel-tcpip-forward");
2391 packet_put_char(0);
2392 packet_put_cstring(address_to_bind);
2393 packet_put_int(port);
2394 packet_send();
2395
2396 permitted_opens[i].listen_port = 0;
2397 permitted_opens[i].port_to_connect = 0;
2398 free(permitted_opens[i].host_to_connect);
2399 permitted_opens[i].host_to_connect = NULL;
2400}
2401
2402/*
Damien Miller5428f641999-11-25 11:54:57 +11002403 * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
2404 * listening for the port, and sends back a success reply (or disconnect
2405 * message if there was an error). This never returns if there was an error.
2406 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002407
Damien Miller4af51302000-04-16 11:18:38 +10002408void
Damien Millere247cc42000-05-07 12:03:14 +10002409channel_input_port_forward_request(int is_root, int gateway_ports)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002410{
Damien Milleraae6c611999-12-06 11:47:28 +11002411 u_short port, host_port;
Damien Miller95def091999-11-25 00:26:21 +11002412 char *hostname;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002413
Damien Miller95def091999-11-25 00:26:21 +11002414 /* Get arguments from the packet. */
2415 port = packet_get_int();
2416 hostname = packet_get_string(NULL);
2417 host_port = packet_get_int();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002418
Damien Millerbac2d8a2000-09-05 16:13:06 +11002419#ifndef HAVE_CYGWIN
Damien Miller5428f641999-11-25 11:54:57 +11002420 /*
2421 * Check that an unprivileged user is not trying to forward a
2422 * privileged port.
2423 */
Damien Miller95def091999-11-25 00:26:21 +11002424 if (port < IPPORT_RESERVED && !is_root)
Darren Tucker9189ff82003-07-03 13:52:04 +10002425 packet_disconnect(
2426 "Requested forwarding of port %d but user is not root.",
2427 port);
2428 if (host_port == 0)
2429 packet_disconnect("Dynamic forwarding denied.");
Damien Millerbac2d8a2000-09-05 16:13:06 +11002430#endif
Darren Tucker9189ff82003-07-03 13:52:04 +10002431
Damien Miller0bc1bd82000-11-13 22:57:25 +11002432 /* Initiate forwarding */
Damien Millerb16461c2002-01-22 23:29:22 +11002433 channel_setup_local_fwd_listener(port, hostname, host_port, gateway_ports);
Damien Miller95def091999-11-25 00:26:21 +11002434
2435 /* Free the argument string. */
2436 xfree(hostname);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002437}
2438
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002439/*
2440 * Permits opening to any host/port if permitted_opens[] is empty. This is
2441 * usually called by the server, because the user could connect to any port
2442 * anyway, and the server has no way to know but to trust the client anyway.
2443 */
2444void
Ben Lindstrom3c36bb22001-12-06 17:55:26 +00002445channel_permit_all_opens(void)
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002446{
2447 if (num_permitted_opens == 0)
2448 all_opens_permitted = 1;
2449}
2450
Ben Lindstroma3700052001-04-05 23:26:32 +00002451void
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002452channel_add_permitted_opens(char *host, int port)
2453{
2454 if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2455 fatal("channel_request_remote_forwarding: too many forwards");
2456 debug("allow port forwarding to host %s port %d", host, port);
2457
2458 permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
2459 permitted_opens[num_permitted_opens].port_to_connect = port;
2460 num_permitted_opens++;
2461
2462 all_opens_permitted = 0;
2463}
2464
Ben Lindstroma3700052001-04-05 23:26:32 +00002465void
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002466channel_clear_permitted_opens(void)
2467{
2468 int i;
2469
2470 for (i = 0; i < num_permitted_opens; i++)
Darren Tuckere7066df2004-05-24 10:18:05 +10002471 if (permitted_opens[i].host_to_connect != NULL)
2472 xfree(permitted_opens[i].host_to_connect);
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002473 num_permitted_opens = 0;
2474
2475}
2476
2477
2478/* return socket to remote host, port */
Ben Lindstrombba81212001-06-25 05:01:22 +00002479static int
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002480connect_to(const char *host, u_short port)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002481{
Damien Miller34132e52000-01-14 15:45:46 +11002482 struct addrinfo hints, *ai, *aitop;
2483 char ntop[NI_MAXHOST], strport[NI_MAXSERV];
2484 int gaierr;
Damien Millerb38eff82000-04-01 11:09:21 +10002485 int sock = -1;
Damien Miller95def091999-11-25 00:26:21 +11002486
Damien Miller34132e52000-01-14 15:45:46 +11002487 memset(&hints, 0, sizeof(hints));
2488 hints.ai_family = IPv4or6;
2489 hints.ai_socktype = SOCK_STREAM;
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002490 snprintf(strport, sizeof strport, "%d", port);
Damien Miller34132e52000-01-14 15:45:46 +11002491 if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) {
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002492 error("connect_to %.100s: unknown host (%s)", host,
2493 gai_strerror(gaierr));
Damien Millerb38eff82000-04-01 11:09:21 +10002494 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002495 }
Damien Miller34132e52000-01-14 15:45:46 +11002496 for (ai = aitop; ai; ai = ai->ai_next) {
2497 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2498 continue;
2499 if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2500 strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002501 error("connect_to: getnameinfo failed");
Damien Miller34132e52000-01-14 15:45:46 +11002502 continue;
2503 }
Damien Miller2372ace2003-05-14 13:42:23 +10002504 sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
Damien Miller34132e52000-01-14 15:45:46 +11002505 if (sock < 0) {
Damien Millerb46b9f32003-01-10 21:45:12 +11002506 if (ai->ai_next == NULL)
2507 error("socket: %.100s", strerror(errno));
2508 else
2509 verbose("socket: %.100s", strerror(errno));
Damien Miller34132e52000-01-14 15:45:46 +11002510 continue;
2511 }
Damien Miller232711f2004-06-15 10:35:30 +10002512 if (set_nonblock(sock) == -1)
2513 fatal("%s: set_nonblock(%d)", __func__, sock);
Ben Lindstrom7ad97102000-12-06 01:42:49 +00002514 if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 &&
2515 errno != EINPROGRESS) {
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002516 error("connect_to %.100s port %s: %.100s", ntop, strport,
Damien Miller34132e52000-01-14 15:45:46 +11002517 strerror(errno));
2518 close(sock);
Kevin Stevesef4eea92001-02-05 12:42:17 +00002519 continue; /* fail -- try next */
Damien Miller34132e52000-01-14 15:45:46 +11002520 }
2521 break; /* success */
2522
2523 }
2524 freeaddrinfo(aitop);
Damien Miller34132e52000-01-14 15:45:46 +11002525 if (!ai) {
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002526 error("connect_to %.100s port %d: failed.", host, port);
Damien Millerb38eff82000-04-01 11:09:21 +10002527 return -1;
2528 }
2529 /* success */
Ben Lindstrom1ebd7a52002-02-26 18:12:51 +00002530 set_nodelay(sock);
Damien Millerb38eff82000-04-01 11:09:21 +10002531 return sock;
2532}
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002533
Damien Miller0bc1bd82000-11-13 22:57:25 +11002534int
Ben Lindstrom173e6462001-07-04 05:15:15 +00002535channel_connect_by_listen_address(u_short listen_port)
Damien Miller0bc1bd82000-11-13 22:57:25 +11002536{
2537 int i;
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002538
Damien Miller0bc1bd82000-11-13 22:57:25 +11002539 for (i = 0; i < num_permitted_opens; i++)
Darren Tuckere7066df2004-05-24 10:18:05 +10002540 if (permitted_opens[i].host_to_connect != NULL &&
2541 permitted_opens[i].listen_port == listen_port)
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002542 return connect_to(
Damien Miller0bc1bd82000-11-13 22:57:25 +11002543 permitted_opens[i].host_to_connect,
2544 permitted_opens[i].port_to_connect);
Ben Lindstromc72745a2000-12-02 19:03:54 +00002545 error("WARNING: Server requests forwarding for unknown listen_port %d",
2546 listen_port);
Damien Miller0bc1bd82000-11-13 22:57:25 +11002547 return -1;
2548}
Damien Millerb38eff82000-04-01 11:09:21 +10002549
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002550/* Check if connecting to that port is permitted and connect. */
2551int
2552channel_connect_to(const char *host, u_short port)
2553{
2554 int i, permit;
2555
2556 permit = all_opens_permitted;
2557 if (!permit) {
2558 for (i = 0; i < num_permitted_opens; i++)
Darren Tuckere7066df2004-05-24 10:18:05 +10002559 if (permitted_opens[i].host_to_connect != NULL &&
2560 permitted_opens[i].port_to_connect == port &&
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002561 strcmp(permitted_opens[i].host_to_connect, host) == 0)
2562 permit = 1;
2563
2564 }
2565 if (!permit) {
Damien Miller996acd22003-04-09 20:59:48 +10002566 logit("Received request to connect to host %.100s port %d, "
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00002567 "but the request was denied.", host, port);
2568 return -1;
2569 }
2570 return connect_to(host, port);
2571}
2572
Damien Miller0e220db2004-06-15 10:34:08 +10002573void
2574channel_send_window_changes(void)
2575{
2576 int i;
2577 struct winsize ws;
2578
2579 for (i = 0; i < channels_alloc; i++) {
2580 if (channels[i] == NULL ||
2581 channels[i]->type != SSH_CHANNEL_OPEN)
2582 continue;
2583 if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
2584 continue;
2585 channel_request_start(i, "window-change", 0);
2586 packet_put_int(ws.ws_col);
2587 packet_put_int(ws.ws_row);
2588 packet_put_int(ws.ws_xpixel);
2589 packet_put_int(ws.ws_ypixel);
2590 packet_send();
2591 }
2592}
2593
Ben Lindstrome9c99912001-06-09 00:41:05 +00002594/* -- X11 forwarding */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002595
Damien Miller5428f641999-11-25 11:54:57 +11002596/*
2597 * Creates an internet domain socket for listening for X11 connections.
Ben Lindstroma9d2c892002-06-23 21:48:28 +00002598 * Returns 0 and a suitable display number for the DISPLAY variable
2599 * stored in display_numberp , or -1 if an error occurs.
Damien Miller5428f641999-11-25 11:54:57 +11002600 */
Kevin Steves366298c2001-12-19 17:58:01 +00002601int
Damien Miller95c249f2002-02-05 12:11:34 +11002602x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
Ben Lindstroma9d2c892002-06-23 21:48:28 +00002603 int single_connection, u_int *display_numberp)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002604{
Damien Millere7378562001-12-21 14:58:35 +11002605 Channel *nc = NULL;
Damien Milleraae6c611999-12-06 11:47:28 +11002606 int display_number, sock;
2607 u_short port;
Damien Miller34132e52000-01-14 15:45:46 +11002608 struct addrinfo hints, *ai, *aitop;
2609 char strport[NI_MAXSERV];
2610 int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002611
Damien Millera34a28b1999-12-14 10:47:15 +11002612 for (display_number = x11_display_offset;
Damien Miller9f0f5c62001-12-21 14:45:46 +11002613 display_number < MAX_DISPLAYS;
2614 display_number++) {
Damien Miller95def091999-11-25 00:26:21 +11002615 port = 6000 + display_number;
Damien Miller34132e52000-01-14 15:45:46 +11002616 memset(&hints, 0, sizeof(hints));
2617 hints.ai_family = IPv4or6;
Damien Miller95c249f2002-02-05 12:11:34 +11002618 hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
Damien Miller34132e52000-01-14 15:45:46 +11002619 hints.ai_socktype = SOCK_STREAM;
2620 snprintf(strport, sizeof strport, "%d", port);
2621 if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
2622 error("getaddrinfo: %.100s", gai_strerror(gaierr));
Kevin Steves366298c2001-12-19 17:58:01 +00002623 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002624 }
Damien Miller34132e52000-01-14 15:45:46 +11002625 for (ai = aitop; ai; ai = ai->ai_next) {
2626 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2627 continue;
Damien Miller2372ace2003-05-14 13:42:23 +10002628 sock = socket(ai->ai_family, ai->ai_socktype,
2629 ai->ai_protocol);
Damien Miller34132e52000-01-14 15:45:46 +11002630 if (sock < 0) {
Damien Miller89d97962000-10-14 12:37:19 +11002631 if ((errno != EINVAL) && (errno != EAFNOSUPPORT)) {
Damien Millere2192732000-01-17 13:22:55 +11002632 error("socket: %.100s", strerror(errno));
Damien Miller3e4dffb2004-06-15 10:27:15 +10002633 freeaddrinfo(aitop);
Kevin Steves366298c2001-12-19 17:58:01 +00002634 return -1;
Damien Millere2192732000-01-17 13:22:55 +11002635 } else {
Damien Millercb5e44a2000-09-29 12:12:36 +11002636 debug("x11_create_display_inet: Socket family %d not supported",
2637 ai->ai_family);
Damien Millere2192732000-01-17 13:22:55 +11002638 continue;
2639 }
Damien Miller34132e52000-01-14 15:45:46 +11002640 }
Kevin Stevesdf75dd22002-06-04 20:52:19 +00002641#ifdef IPV6_V6ONLY
2642 if (ai->ai_family == AF_INET6) {
2643 int on = 1;
2644 if (setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) < 0)
2645 error("setsockopt IPV6_V6ONLY: %.100s", strerror(errno));
2646 }
2647#endif
Damien Miller34132e52000-01-14 15:45:46 +11002648 if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
Damien Millerfbdeece2003-09-02 22:52:31 +10002649 debug2("bind port %d: %.100s", port, strerror(errno));
Damien Miller34132e52000-01-14 15:45:46 +11002650 close(sock);
Damien Miller3c7eeb22000-03-03 22:35:33 +11002651
2652 if (ai->ai_next)
2653 continue;
2654
Damien Miller34132e52000-01-14 15:45:46 +11002655 for (n = 0; n < num_socks; n++) {
Damien Miller34132e52000-01-14 15:45:46 +11002656 close(socks[n]);
2657 }
2658 num_socks = 0;
2659 break;
2660 }
2661 socks[num_socks++] = sock;
Damien Miller7bcb0892000-03-11 20:45:40 +11002662#ifndef DONT_TRY_OTHER_AF
Damien Miller34132e52000-01-14 15:45:46 +11002663 if (num_socks == NUM_SOCKS)
2664 break;
Damien Miller7bcb0892000-03-11 20:45:40 +11002665#else
Kevin Stevesdf75dd22002-06-04 20:52:19 +00002666 if (x11_use_localhost) {
2667 if (num_socks == NUM_SOCKS)
2668 break;
2669 } else {
2670 break;
2671 }
Damien Miller7bcb0892000-03-11 20:45:40 +11002672#endif
Damien Miller95def091999-11-25 00:26:21 +11002673 }
Ben Lindstrom87b147f2001-01-25 00:41:12 +00002674 freeaddrinfo(aitop);
Damien Miller34132e52000-01-14 15:45:46 +11002675 if (num_socks > 0)
2676 break;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002677 }
Damien Miller95def091999-11-25 00:26:21 +11002678 if (display_number >= MAX_DISPLAYS) {
2679 error("Failed to allocate internet-domain X11 display socket.");
Kevin Steves366298c2001-12-19 17:58:01 +00002680 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002681 }
Damien Miller95def091999-11-25 00:26:21 +11002682 /* Start listening for connections on the socket. */
Damien Miller34132e52000-01-14 15:45:46 +11002683 for (n = 0; n < num_socks; n++) {
2684 sock = socks[n];
Darren Tucker3175eb92003-12-09 19:15:11 +11002685 if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
Damien Miller34132e52000-01-14 15:45:46 +11002686 error("listen: %.100s", strerror(errno));
Damien Miller34132e52000-01-14 15:45:46 +11002687 close(sock);
Kevin Steves366298c2001-12-19 17:58:01 +00002688 return -1;
Damien Miller34132e52000-01-14 15:45:46 +11002689 }
Damien Miller95def091999-11-25 00:26:21 +11002690 }
Damien Miller34132e52000-01-14 15:45:46 +11002691
Damien Miller34132e52000-01-14 15:45:46 +11002692 /* Allocate a channel for each socket. */
2693 for (n = 0; n < num_socks; n++) {
2694 sock = socks[n];
Damien Millere7378562001-12-21 14:58:35 +11002695 nc = channel_new("x11 listener",
Damien Millerbd483e72000-04-30 10:00:53 +10002696 SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
2697 CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
Damien Millerb1ca8bb2003-05-14 13:45:42 +10002698 0, "X11 inet listener", 1);
Damien Miller699d0032002-02-08 22:07:16 +11002699 nc->single_connection = single_connection;
Damien Miller34132e52000-01-14 15:45:46 +11002700 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002701
Kevin Steves366298c2001-12-19 17:58:01 +00002702 /* Return the display number for the DISPLAY environment variable. */
Ben Lindstroma9d2c892002-06-23 21:48:28 +00002703 *display_numberp = display_number;
2704 return (0);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002705}
2706
Ben Lindstrombba81212001-06-25 05:01:22 +00002707static int
Ben Lindstrom46c16222000-12-22 01:43:59 +00002708connect_local_xsocket(u_int dnr)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002709{
Damien Miller95def091999-11-25 00:26:21 +11002710 int sock;
2711 struct sockaddr_un addr;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002712
Damien Miller3afe3752001-12-21 12:39:51 +11002713 sock = socket(AF_UNIX, SOCK_STREAM, 0);
2714 if (sock < 0)
2715 error("socket: %.100s", strerror(errno));
2716 memset(&addr, 0, sizeof(addr));
2717 addr.sun_family = AF_UNIX;
2718 snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
2719 if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0)
2720 return sock;
2721 close(sock);
Damien Miller95def091999-11-25 00:26:21 +11002722 error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
2723 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002724}
2725
Damien Millerbd483e72000-04-30 10:00:53 +10002726int
2727x11_connect_display(void)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002728{
Damien Miller398e1cf2002-02-05 11:52:13 +11002729 int display_number, sock = 0;
Damien Miller95def091999-11-25 00:26:21 +11002730 const char *display;
Damien Millerbd483e72000-04-30 10:00:53 +10002731 char buf[1024], *cp;
Damien Miller34132e52000-01-14 15:45:46 +11002732 struct addrinfo hints, *ai, *aitop;
2733 char strport[NI_MAXSERV];
2734 int gaierr;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002735
Damien Miller95def091999-11-25 00:26:21 +11002736 /* Try to open a socket for the local X server. */
2737 display = getenv("DISPLAY");
2738 if (!display) {
2739 error("DISPLAY not set.");
Damien Millerbd483e72000-04-30 10:00:53 +10002740 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002741 }
Damien Miller5428f641999-11-25 11:54:57 +11002742 /*
2743 * Now we decode the value of the DISPLAY variable and make a
2744 * connection to the real X server.
2745 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002746
Damien Miller5428f641999-11-25 11:54:57 +11002747 /*
2748 * Check if it is a unix domain socket. Unix domain displays are in
2749 * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
2750 */
Damien Miller95def091999-11-25 00:26:21 +11002751 if (strncmp(display, "unix:", 5) == 0 ||
2752 display[0] == ':') {
2753 /* Connect to the unix domain socket. */
2754 if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) {
2755 error("Could not parse display number from DISPLAY: %.100s",
Damien Miller9f0f5c62001-12-21 14:45:46 +11002756 display);
Damien Millerbd483e72000-04-30 10:00:53 +10002757 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002758 }
2759 /* Create a socket. */
2760 sock = connect_local_xsocket(display_number);
2761 if (sock < 0)
Damien Millerbd483e72000-04-30 10:00:53 +10002762 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002763
2764 /* OK, we now have a connection to the display. */
Damien Millerbd483e72000-04-30 10:00:53 +10002765 return sock;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002766 }
Damien Miller5428f641999-11-25 11:54:57 +11002767 /*
2768 * Connect to an inet socket. The DISPLAY value is supposedly
2769 * hostname:d[.s], where hostname may also be numeric IP address.
2770 */
Ben Lindstromccd8d072001-12-07 17:26:48 +00002771 strlcpy(buf, display, sizeof(buf));
Damien Miller95def091999-11-25 00:26:21 +11002772 cp = strchr(buf, ':');
2773 if (!cp) {
2774 error("Could not find ':' in DISPLAY: %.100s", display);
Damien Millerbd483e72000-04-30 10:00:53 +10002775 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002776 }
Damien Miller95def091999-11-25 00:26:21 +11002777 *cp = 0;
Damien Miller5428f641999-11-25 11:54:57 +11002778 /* buf now contains the host name. But first we parse the display number. */
Damien Miller95def091999-11-25 00:26:21 +11002779 if (sscanf(cp + 1, "%d", &display_number) != 1) {
2780 error("Could not parse display number from DISPLAY: %.100s",
Damien Miller9f0f5c62001-12-21 14:45:46 +11002781 display);
Damien Millerbd483e72000-04-30 10:00:53 +10002782 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002783 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002784
Damien Miller34132e52000-01-14 15:45:46 +11002785 /* Look up the host address */
2786 memset(&hints, 0, sizeof(hints));
2787 hints.ai_family = IPv4or6;
2788 hints.ai_socktype = SOCK_STREAM;
2789 snprintf(strport, sizeof strport, "%d", 6000 + display_number);
2790 if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
2791 error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr));
Damien Millerbd483e72000-04-30 10:00:53 +10002792 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002793 }
Damien Miller34132e52000-01-14 15:45:46 +11002794 for (ai = aitop; ai; ai = ai->ai_next) {
2795 /* Create a socket. */
Damien Miller2372ace2003-05-14 13:42:23 +10002796 sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
Damien Miller34132e52000-01-14 15:45:46 +11002797 if (sock < 0) {
Damien Millerfbdeece2003-09-02 22:52:31 +10002798 debug2("socket: %.100s", strerror(errno));
Damien Millerb38eff82000-04-01 11:09:21 +10002799 continue;
2800 }
2801 /* Connect it to the display. */
2802 if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
Damien Millerfbdeece2003-09-02 22:52:31 +10002803 debug2("connect %.100s port %d: %.100s", buf,
Damien Millerb38eff82000-04-01 11:09:21 +10002804 6000 + display_number, strerror(errno));
2805 close(sock);
2806 continue;
2807 }
2808 /* Success */
2809 break;
Damien Miller34132e52000-01-14 15:45:46 +11002810 }
Damien Miller34132e52000-01-14 15:45:46 +11002811 freeaddrinfo(aitop);
2812 if (!ai) {
Damien Miller4af51302000-04-16 11:18:38 +10002813 error("connect %.100s port %d: %.100s", buf, 6000 + display_number,
Damien Miller34132e52000-01-14 15:45:46 +11002814 strerror(errno));
Damien Millerbd483e72000-04-30 10:00:53 +10002815 return -1;
Damien Miller95def091999-11-25 00:26:21 +11002816 }
Damien Miller398e1cf2002-02-05 11:52:13 +11002817 set_nodelay(sock);
Damien Millerbd483e72000-04-30 10:00:53 +10002818 return sock;
2819}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002820
Damien Millerbd483e72000-04-30 10:00:53 +10002821/*
2822 * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
2823 * the remote channel number. We should do whatever we want, and respond
2824 * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
2825 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002826
Damien Millerbd483e72000-04-30 10:00:53 +10002827void
Damien Miller630d6f42002-01-22 23:17:30 +11002828x11_input_open(int type, u_int32_t seq, void *ctxt)
Damien Millerbd483e72000-04-30 10:00:53 +10002829{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002830 Channel *c = NULL;
2831 int remote_id, sock = 0;
Damien Millerbd483e72000-04-30 10:00:53 +10002832 char *remote_host;
Damien Millerbd483e72000-04-30 10:00:53 +10002833
2834 debug("Received X11 open request.");
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002835
2836 remote_id = packet_get_int();
Ben Lindstrome9c99912001-06-09 00:41:05 +00002837
2838 if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002839 remote_host = packet_get_string(NULL);
2840 } else {
2841 remote_host = xstrdup("unknown (remote did not supply name)");
2842 }
Damien Miller48b03fc2002-01-22 23:11:40 +11002843 packet_check_eom();
Damien Millerbd483e72000-04-30 10:00:53 +10002844
2845 /* Obtain a connection to the real X display. */
2846 sock = x11_connect_display();
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002847 if (sock != -1) {
2848 /* Allocate a channel for this connection. */
2849 c = channel_new("connected x11 socket",
2850 SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
2851 remote_host, 1);
Damien Miller699d0032002-02-08 22:07:16 +11002852 c->remote_id = remote_id;
2853 c->force_drain = 1;
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002854 }
Damien Millerb1ca8bb2003-05-14 13:45:42 +10002855 xfree(remote_host);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002856 if (c == NULL) {
Damien Millerbd483e72000-04-30 10:00:53 +10002857 /* Send refusal to the remote host. */
2858 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002859 packet_put_int(remote_id);
Damien Millerbd483e72000-04-30 10:00:53 +10002860 } else {
Damien Millerbd483e72000-04-30 10:00:53 +10002861 /* Send a confirmation to the remote host. */
2862 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002863 packet_put_int(remote_id);
2864 packet_put_int(c->self);
Damien Millerbd483e72000-04-30 10:00:53 +10002865 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002866 packet_send();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002867}
2868
Damien Miller69b69aa2000-10-28 14:19:58 +11002869/* dummy protocol handler that denies SSH-1 requests (agent/x11) */
2870void
Damien Miller630d6f42002-01-22 23:17:30 +11002871deny_input_open(int type, u_int32_t seq, void *ctxt)
Damien Miller69b69aa2000-10-28 14:19:58 +11002872{
2873 int rchan = packet_get_int();
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +00002874
Ben Lindstrom1c37c6a2001-12-06 18:00:18 +00002875 switch (type) {
Damien Miller69b69aa2000-10-28 14:19:58 +11002876 case SSH_SMSG_AGENT_OPEN:
2877 error("Warning: ssh server tried agent forwarding.");
2878 break;
2879 case SSH_SMSG_X11_OPEN:
2880 error("Warning: ssh server tried X11 forwarding.");
2881 break;
2882 default:
Damien Miller630d6f42002-01-22 23:17:30 +11002883 error("deny_input_open: type %d", type);
Damien Miller69b69aa2000-10-28 14:19:58 +11002884 break;
2885 }
2886 error("Warning: this is probably a break in attempt by a malicious server.");
2887 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2888 packet_put_int(rchan);
2889 packet_send();
2890}
2891
Damien Miller5428f641999-11-25 11:54:57 +11002892/*
2893 * Requests forwarding of X11 connections, generates fake authentication
2894 * data, and enables authentication spoofing.
Ben Lindstrome9c99912001-06-09 00:41:05 +00002895 * This should be called in the client only.
Damien Miller5428f641999-11-25 11:54:57 +11002896 */
Damien Miller4af51302000-04-16 11:18:38 +10002897void
Damien Millerbd483e72000-04-30 10:00:53 +10002898x11_request_forwarding_with_spoofing(int client_session_id,
2899 const char *proto, const char *data)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002900{
Ben Lindstrom46c16222000-12-22 01:43:59 +00002901 u_int data_len = (u_int) strlen(data) / 2;
Ben Lindstromb3211a82001-02-10 22:33:19 +00002902 u_int i, value, len;
Damien Miller95def091999-11-25 00:26:21 +11002903 char *new_data;
2904 int screen_number;
2905 const char *cp;
2906 u_int32_t rand = 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002907
Damien Miller95def091999-11-25 00:26:21 +11002908 cp = getenv("DISPLAY");
2909 if (cp)
2910 cp = strchr(cp, ':');
2911 if (cp)
2912 cp = strchr(cp, '.');
2913 if (cp)
2914 screen_number = atoi(cp + 1);
2915 else
2916 screen_number = 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002917
Damien Miller95def091999-11-25 00:26:21 +11002918 /* Save protocol name. */
2919 x11_saved_proto = xstrdup(proto);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002920
Damien Miller5428f641999-11-25 11:54:57 +11002921 /*
2922 * Extract real authentication data and generate fake data of the
2923 * same length.
2924 */
Damien Miller95def091999-11-25 00:26:21 +11002925 x11_saved_data = xmalloc(data_len);
2926 x11_fake_data = xmalloc(data_len);
2927 for (i = 0; i < data_len; i++) {
2928 if (sscanf(data + 2 * i, "%2x", &value) != 1)
2929 fatal("x11_request_forwarding: bad authentication data: %.100s", data);
2930 if (i % 4 == 0)
2931 rand = arc4random();
2932 x11_saved_data[i] = value;
2933 x11_fake_data[i] = rand & 0xff;
2934 rand >>= 8;
2935 }
2936 x11_saved_data_len = data_len;
2937 x11_fake_data_len = data_len;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002938
Damien Miller95def091999-11-25 00:26:21 +11002939 /* Convert the fake data into hex. */
Ben Lindstromb3211a82001-02-10 22:33:19 +00002940 len = 2 * data_len + 1;
2941 new_data = xmalloc(len);
Damien Miller95def091999-11-25 00:26:21 +11002942 for (i = 0; i < data_len; i++)
Ben Lindstromb3211a82001-02-10 22:33:19 +00002943 snprintf(new_data + 2 * i, len - 2 * i,
2944 "%02x", (u_char) x11_fake_data[i]);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002945
Damien Miller95def091999-11-25 00:26:21 +11002946 /* Send the request packet. */
Damien Millerbd483e72000-04-30 10:00:53 +10002947 if (compat20) {
2948 channel_request_start(client_session_id, "x11-req", 0);
2949 packet_put_char(0); /* XXX bool single connection */
2950 } else {
2951 packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
2952 }
2953 packet_put_cstring(proto);
2954 packet_put_cstring(new_data);
Damien Miller95def091999-11-25 00:26:21 +11002955 packet_put_int(screen_number);
2956 packet_send();
2957 packet_write_wait();
2958 xfree(new_data);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002959}
2960
Ben Lindstrome9c99912001-06-09 00:41:05 +00002961
2962/* -- agent forwarding */
2963
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002964/* Sends a message to the server to request authentication fd forwarding. */
2965
Damien Miller4af51302000-04-16 11:18:38 +10002966void
Ben Lindstrom3c36bb22001-12-06 17:55:26 +00002967auth_request_forwarding(void)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002968{
Damien Miller95def091999-11-25 00:26:21 +11002969 packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
2970 packet_send();
2971 packet_write_wait();
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002972}