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djm@openbsd.org218e6f92017-09-24 13:45:34 +00001/* $OpenBSD: channels.c,v 1.375 2017/09/24 13:45:34 djm Exp $ */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002/*
Damien Miller95def091999-11-25 00:26:21 +11003 * Author: Tatu Ylonen <ylo@cs.hut.fi>
Damien Miller95def091999-11-25 00:26:21 +11004 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5 * All rights reserved
Damien Miller95def091999-11-25 00:26:21 +11006 * This file contains functions for generic socket connection forwarding.
7 * There is also code for initiating connection forwarding for X11 connections,
8 * arbitrary tcp/ip connections, and the authentication agent connection.
Damien Miller4af51302000-04-16 11:18:38 +10009 *
Damien Millere4340be2000-09-16 13:29:08 +110010 * As far as I am concerned, the code I have written for this software
11 * can be used freely for any purpose. Any derived versions of this
12 * software must be clearly marked as such, and if the derived work is
13 * incompatible with the protocol description in the RFC file, it must be
14 * called by a name other than "ssh" or "Secure Shell".
15 *
Damien Miller33b13562000-04-04 14:38:59 +100016 * SSH2 support added by Markus Friedl.
Damien Millera90fc082002-01-22 23:19:38 +110017 * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
Damien Millere4340be2000-09-16 13:29:08 +110018 * Copyright (c) 1999 Dug Song. All rights reserved.
19 * Copyright (c) 1999 Theo de Raadt. All rights reserved.
20 *
21 * Redistribution and use in source and binary forms, with or without
22 * modification, are permitted provided that the following conditions
23 * are met:
24 * 1. Redistributions of source code must retain the above copyright
25 * notice, this list of conditions and the following disclaimer.
26 * 2. Redistributions in binary form must reproduce the above copyright
27 * notice, this list of conditions and the following disclaimer in the
28 * documentation and/or other materials provided with the distribution.
29 *
30 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
31 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
33 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
34 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
35 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
39 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
Damien Miller95def091999-11-25 00:26:21 +110040 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +100041
42#include "includes.h"
Damien Miller17e91c02006-03-15 11:28:34 +110043
Damien Miller574c41f2006-03-15 11:40:10 +110044#include <sys/types.h>
Damien Miller7acefbb2014-07-18 14:11:24 +100045#include <sys/stat.h>
Damien Millerd7834352006-08-05 12:39:39 +100046#include <sys/ioctl.h>
Damien Miller574c41f2006-03-15 11:40:10 +110047#include <sys/un.h>
Damien Millerefc04e72006-07-10 20:26:27 +100048#include <sys/socket.h>
Damien Miller9aec9192006-08-05 10:57:45 +100049#ifdef HAVE_SYS_TIME_H
50# include <sys/time.h>
51#endif
Damien Millerefc04e72006-07-10 20:26:27 +100052
53#include <netinet/in.h>
54#include <arpa/inet.h>
Damien Miller99bd21e2006-03-15 11:11:28 +110055
Darren Tucker39972492006-07-12 22:22:46 +100056#include <errno.h>
Darren Tucker6e7fe1c2010-01-08 17:07:22 +110057#include <fcntl.h>
djm@openbsd.orgdbee4112017-09-12 06:32:07 +000058#include <limits.h>
Damien Millerb8fe89c2006-07-24 14:51:00 +100059#include <netdb.h>
djm@openbsd.orgdbee4112017-09-12 06:32:07 +000060#include <stdarg.h>
Darren Tucker37f92202015-02-23 03:07:24 +110061#ifdef HAVE_STDINT_H
djm@openbsd.orgdbee4112017-09-12 06:32:07 +000062 #include <stdint.h>
Darren Tucker37f92202015-02-23 03:07:24 +110063#endif
Damien Millera7a73ee2006-08-05 11:37:59 +100064#include <stdio.h>
Damien Millere7a1e5c2006-08-05 11:34:19 +100065#include <stdlib.h>
Damien Millere3476ed2006-07-24 14:13:33 +100066#include <string.h>
Damien Miller99bd21e2006-03-15 11:11:28 +110067#include <termios.h>
Damien Millere6b3b612006-07-24 14:01:23 +100068#include <unistd.h>
Damien Millerd4a8b7e1999-10-27 13:42:43 +100069
Damien Millerb84886b2008-05-19 15:05:07 +100070#include "openbsd-compat/sys-queue.h"
Damien Millerd7834352006-08-05 12:39:39 +100071#include "xmalloc.h"
Damien Millerd4a8b7e1999-10-27 13:42:43 +100072#include "ssh.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000073#include "ssh2.h"
markus@openbsd.org8d057842016-09-30 09:19:13 +000074#include "ssherr.h"
djm@openbsd.orgdbee4112017-09-12 06:32:07 +000075#include "sshbuf.h"
Damien Millerd4a8b7e1999-10-27 13:42:43 +100076#include "packet.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000077#include "log.h"
78#include "misc.h"
Damien Millerd4a8b7e1999-10-27 13:42:43 +100079#include "channels.h"
Damien Millerd4a8b7e1999-10-27 13:42:43 +100080#include "compat.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000081#include "canohost.h"
Damien Miller994cf142000-07-21 10:19:44 +100082#include "key.h"
83#include "authfd.h"
Damien Miller3afe3752001-12-21 12:39:51 +110084#include "pathnames.h"
Damien Millerd4a8b7e1999-10-27 13:42:43 +100085
djm@openbsd.orgdbee4112017-09-12 06:32:07 +000086/* -- agent forwarding */
87#define NUM_SOCKS 10
Damien Millerd4a8b7e1999-10-27 13:42:43 +100088
Ben Lindstrome9c99912001-06-09 00:41:05 +000089/* -- tcp forwarding */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +000090/* special-case port number meaning allow any port */
91#define FWD_PERMIT_ANY_PORT 0
92
93/* special-case wildcard meaning allow any host */
94#define FWD_PERMIT_ANY_HOST "*"
95
96/* -- X11 forwarding */
97/* Maximum number of fake X11 displays to try. */
98#define MAX_DISPLAYS 1000
Damien Millerd4a8b7e1999-10-27 13:42:43 +100099
Damien Miller5428f641999-11-25 11:54:57 +1100100/*
101 * Data structure for storing which hosts are permitted for forward requests.
102 * The local sides of any remote forwards are stored in this array to prevent
103 * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
104 * network (which might be behind a firewall).
105 */
Damien Miller7acefbb2014-07-18 14:11:24 +1000106/* XXX: streamlocal wants a path instead of host:port */
107/* Overload host_to_connect; we could just make this match Forward */
108/* XXX - can we use listen_host instead of listen_path? */
Damien Miller95def091999-11-25 00:26:21 +1100109typedef struct {
Damien Millerb38eff82000-04-01 11:09:21 +1000110 char *host_to_connect; /* Connect to 'host'. */
Damien Miller7acefbb2014-07-18 14:11:24 +1000111 int port_to_connect; /* Connect to 'port'. */
Damien Miller4b3ed642014-07-02 15:29:40 +1000112 char *listen_host; /* Remote side should listen address. */
Damien Miller7acefbb2014-07-18 14:11:24 +1000113 char *listen_path; /* Remote side should listen path. */
114 int listen_port; /* Remote side should listen port. */
markus@openbsd.org8d057842016-09-30 09:19:13 +0000115 Channel *downstream; /* Downstream mux*/
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000116} ForwardPermission;
117
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000118typedef void chan_fn(struct ssh *, Channel *c,
119 fd_set *readset, fd_set *writeset);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000120
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000121/* Master structure for channels state */
122struct ssh_channels {
123 /*
124 * Pointer to an array containing all allocated channels. The array
125 * is dynamically extended as needed.
126 */
127 Channel **channels;
Damien Miller9b439df2006-07-24 14:04:00 +1000128
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000129 /*
130 * Size of the channel array. All slots of the array must always be
131 * initialized (at least the type field); unused slots set to NULL
132 */
133 u_int channels_alloc;
Damien Miller9b439df2006-07-24 14:04:00 +1000134
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000135 /*
136 * Maximum file descriptor value used in any of the channels. This is
137 * updated in channel_new.
138 */
139 int channel_max_fd;
Damien Miller9b439df2006-07-24 14:04:00 +1000140
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000141 /*
142 * 'channel_pre*' are called just before select() to add any bits
143 * relevant to channels in the select bitmasks.
144 *
145 * 'channel_post*': perform any appropriate operations for
146 * channels which have events pending.
147 */
148 chan_fn **channel_pre;
149 chan_fn **channel_post;
Darren Tucker1338b9e2011-10-02 18:57:35 +1100150
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000151 /* -- tcp forwarding */
dtucker@openbsd.orgd7eabc82016-07-19 11:38:53 +0000152
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000153 /* List of all permitted host/port pairs to connect by the user. */
154 ForwardPermission *permitted_opens;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000155
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000156 /* List of all permitted host/port pairs to connect by the admin. */
157 ForwardPermission *permitted_adm_opens;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000158
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000159 /*
160 * Number of permitted host/port pairs in the array permitted by
161 * the user.
162 */
163 u_int num_permitted_opens;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000164
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000165 /*
166 * Number of permitted host/port pair in the array permitted by
167 * the admin.
168 */
169 u_int num_adm_permitted_opens;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000170
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000171 /*
172 * If this is true, all opens are permitted. This is the case on
173 * the server on which we have to trust the client anyway, and the
174 * user could do anything after logging in anyway.
175 */
176 int all_opens_permitted;
Damien Miller13390022005-07-06 09:44:19 +1000177
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000178 /* -- X11 forwarding */
Ben Lindstrome9c99912001-06-09 00:41:05 +0000179
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000180 /* Saved X11 local (client) display. */
181 char *x11_saved_display;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000182
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000183 /* Saved X11 authentication protocol name. */
184 char *x11_saved_proto;
djm@openbsd.org1bf477d2015-07-01 02:26:31 +0000185
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000186 /* Saved X11 authentication data. This is the real data. */
187 char *x11_saved_data;
188 u_int x11_saved_data_len;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000189
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000190 /* Deadline after which all X11 connections are refused */
191 u_int x11_refuse_time;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000192
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000193 /*
194 * Fake X11 authentication data. This is what the server will be
195 * sending us; we should replace any occurrences of this by the
196 * real data.
197 */
198 u_char *x11_fake_data;
199 u_int x11_fake_data_len;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000200
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000201 /* AF_UNSPEC or AF_INET or AF_INET6 */
202 int IPv4or6;
203};
Ben Lindstrom226cfa02001-01-22 05:34:40 +0000204
Ben Lindstrome9c99912001-06-09 00:41:05 +0000205/* helper */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000206static void port_open_helper(struct ssh *ssh, Channel *c, char *rtype);
markus@openbsd.org8d057842016-09-30 09:19:13 +0000207static const char *channel_rfwd_bind_host(const char *listen_host);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000208
Damien Millerbd740252008-05-19 15:37:09 +1000209/* non-blocking connect helpers */
210static int connect_next(struct channel_connect *);
211static void channel_connect_ctx_free(struct channel_connect *);
markus@openbsd.org609d7a62017-09-21 19:16:53 +0000212static Channel *rdynamic_connect_prepare(struct ssh *, char *, char *);
213static int rdynamic_connect_finish(struct ssh *, Channel *);
Damien Millerbd740252008-05-19 15:37:09 +1000214
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000215/* Setup helper */
216static void channel_handler_init(struct ssh_channels *sc);
217
Ben Lindstrome9c99912001-06-09 00:41:05 +0000218/* -- channel core */
Damien Millerb38eff82000-04-01 11:09:21 +1000219
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000220void
221channel_init_channels(struct ssh *ssh)
222{
223 struct ssh_channels *sc;
224
225 if ((sc = calloc(1, sizeof(*sc))) == NULL ||
226 (sc->channel_pre = calloc(SSH_CHANNEL_MAX_TYPE,
227 sizeof(*sc->channel_pre))) == NULL ||
228 (sc->channel_post = calloc(SSH_CHANNEL_MAX_TYPE,
229 sizeof(*sc->channel_post))) == NULL)
230 fatal("%s: allocation failed", __func__);
231 sc->channels_alloc = 10;
232 sc->channels = xcalloc(sc->channels_alloc, sizeof(*sc->channels));
233 sc->IPv4or6 = AF_UNSPEC;
234 channel_handler_init(sc);
235
236 ssh->chanctxt = sc;
237}
238
Damien Millerb38eff82000-04-01 11:09:21 +1000239Channel *
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000240channel_by_id(struct ssh *ssh, int id)
Damien Millerb38eff82000-04-01 11:09:21 +1000241{
242 Channel *c;
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000243
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000244 if (id < 0 || (u_int)id >= ssh->chanctxt->channels_alloc) {
245 logit("%s: %d: bad id", __func__, id);
Damien Millerb38eff82000-04-01 11:09:21 +1000246 return NULL;
247 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000248 c = ssh->chanctxt->channels[id];
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000249 if (c == NULL) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000250 logit("%s: %d: bad id: channel free", __func__, id);
Damien Millerb38eff82000-04-01 11:09:21 +1000251 return NULL;
252 }
253 return c;
254}
255
markus@openbsd.org8d057842016-09-30 09:19:13 +0000256Channel *
djm@openbsd.org9f532292017-09-12 06:35:31 +0000257channel_by_remote_id(struct ssh *ssh, u_int remote_id)
markus@openbsd.org8d057842016-09-30 09:19:13 +0000258{
259 Channel *c;
260 u_int i;
261
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000262 for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
263 c = ssh->chanctxt->channels[i];
djm@openbsd.org9f532292017-09-12 06:35:31 +0000264 if (c != NULL && c->have_remote_id && c->remote_id == remote_id)
markus@openbsd.org8d057842016-09-30 09:19:13 +0000265 return c;
266 }
267 return NULL;
268}
269
Damien Miller5428f641999-11-25 11:54:57 +1100270/*
Damien Millerd47c62a2005-12-13 19:33:57 +1100271 * Returns the channel if it is allowed to receive protocol messages.
272 * Private channels, like listening sockets, may not receive messages.
273 */
274Channel *
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000275channel_lookup(struct ssh *ssh, int id)
Damien Millerd47c62a2005-12-13 19:33:57 +1100276{
277 Channel *c;
278
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000279 if ((c = channel_by_id(ssh, id)) == NULL)
280 return NULL;
Damien Millerd47c62a2005-12-13 19:33:57 +1100281
Damien Millerd62f2ca2006-03-26 13:57:41 +1100282 switch (c->type) {
Damien Millerd47c62a2005-12-13 19:33:57 +1100283 case SSH_CHANNEL_X11_OPEN:
284 case SSH_CHANNEL_LARVAL:
285 case SSH_CHANNEL_CONNECTING:
286 case SSH_CHANNEL_DYNAMIC:
markus@openbsd.org609d7a62017-09-21 19:16:53 +0000287 case SSH_CHANNEL_RDYNAMIC_OPEN:
288 case SSH_CHANNEL_RDYNAMIC_FINISH:
Damien Millerd47c62a2005-12-13 19:33:57 +1100289 case SSH_CHANNEL_OPENING:
290 case SSH_CHANNEL_OPEN:
Damien Miller36187092013-06-10 13:07:11 +1000291 case SSH_CHANNEL_ABANDONED:
markus@openbsd.org8d057842016-09-30 09:19:13 +0000292 case SSH_CHANNEL_MUX_PROXY:
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000293 return c;
Damien Millerd47c62a2005-12-13 19:33:57 +1100294 }
295 logit("Non-public channel %d, type %d.", id, c->type);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000296 return NULL;
Damien Millerd47c62a2005-12-13 19:33:57 +1100297}
298
299/*
Damien Millere247cc42000-05-07 12:03:14 +1000300 * Register filedescriptors for a channel, used when allocating a channel or
Damien Miller6f83b8e2000-05-02 09:23:45 +1000301 * when the channel consumer/producer is ready, e.g. shell exec'd
Damien Miller5428f641999-11-25 11:54:57 +1100302 */
Ben Lindstrombba81212001-06-25 05:01:22 +0000303static void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000304channel_register_fds(struct ssh *ssh, Channel *c, int rfd, int wfd, int efd,
Darren Tuckered3cdc02008-06-16 23:29:18 +1000305 int extusage, int nonblock, int is_tty)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000306{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000307 struct ssh_channels *sc = ssh->chanctxt;
308
Damien Miller95def091999-11-25 00:26:21 +1100309 /* Update the maximum file descriptor value. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000310 sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, rfd);
311 sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, wfd);
312 sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, efd);
Damien Miller5e953212001-01-30 09:14:00 +1100313
Darren Tucker6e7fe1c2010-01-08 17:07:22 +1100314 if (rfd != -1)
315 fcntl(rfd, F_SETFD, FD_CLOEXEC);
316 if (wfd != -1 && wfd != rfd)
317 fcntl(wfd, F_SETFD, FD_CLOEXEC);
318 if (efd != -1 && efd != rfd && efd != wfd)
319 fcntl(efd, F_SETFD, FD_CLOEXEC);
Damien Millere247cc42000-05-07 12:03:14 +1000320
Damien Miller6f83b8e2000-05-02 09:23:45 +1000321 c->rfd = rfd;
322 c->wfd = wfd;
323 c->sock = (rfd == wfd) ? rfd : -1;
324 c->efd = efd;
325 c->extended_usage = extusage;
Damien Miller69b69aa2000-10-28 14:19:58 +1100326
Darren Tuckered3cdc02008-06-16 23:29:18 +1000327 if ((c->isatty = is_tty) != 0)
Damien Millerfbdeece2003-09-02 22:52:31 +1000328 debug2("channel %d: rfd %d isatty", c->self, c->rfd);
Damien Millerc192a4c2013-08-01 14:29:20 +1000329#ifdef _AIX
330 /* XXX: Later AIX versions can't push as much data to tty */
Darren Tucker1a48aec2008-06-16 23:35:56 +1000331 c->wfd_isatty = is_tty || isatty(c->wfd);
Damien Millerc192a4c2013-08-01 14:29:20 +1000332#endif
Damien Miller79438cc2001-02-16 12:34:57 +1100333
Damien Miller69b69aa2000-10-28 14:19:58 +1100334 /* enable nonblocking mode */
335 if (nonblock) {
336 if (rfd != -1)
337 set_nonblock(rfd);
338 if (wfd != -1)
339 set_nonblock(wfd);
340 if (efd != -1)
341 set_nonblock(efd);
342 }
Damien Miller6f83b8e2000-05-02 09:23:45 +1000343}
344
345/*
346 * Allocate a new channel object and set its type and socket. This will cause
347 * remote_name to be freed.
348 */
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000349Channel *
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000350channel_new(struct ssh *ssh, char *ctype, int type, int rfd, int wfd, int efd,
Ben Lindstrom4fed2be2002-06-25 23:17:36 +0000351 u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
Damien Miller6f83b8e2000-05-02 09:23:45 +1000352{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000353 struct ssh_channels *sc = ssh->chanctxt;
354 u_int i, found;
Damien Miller6f83b8e2000-05-02 09:23:45 +1000355 Channel *c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000356
Damien Miller95def091999-11-25 00:26:21 +1100357 /* Try to find a free slot where to put the new channel. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000358 for (i = 0; i < sc->channels_alloc; i++) {
359 if (sc->channels[i] == NULL) {
Damien Miller95def091999-11-25 00:26:21 +1100360 /* Found a free slot. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000361 found = i;
Damien Miller95def091999-11-25 00:26:21 +1100362 break;
363 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000364 }
365 if (i >= sc->channels_alloc) {
366 /*
367 * There are no free slots. Take last+1 slot and expand
368 * the array.
369 */
370 found = sc->channels_alloc;
371 if (sc->channels_alloc > CHANNELS_MAX_CHANNELS)
372 fatal("%s: internal error: channels_alloc %d too big",
373 __func__, sc->channels_alloc);
374 sc->channels = xrecallocarray(sc->channels, sc->channels_alloc,
375 sc->channels_alloc + 10, sizeof(*sc->channels));
376 sc->channels_alloc += 10;
377 debug2("channel: expanding %d", sc->channels_alloc);
Damien Miller95def091999-11-25 00:26:21 +1100378 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000379 /* Initialize and return new channel. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000380 c = sc->channels[found] = xcalloc(1, sizeof(Channel));
381 if ((c->input = sshbuf_new()) == NULL ||
382 (c->output = sshbuf_new()) == NULL ||
383 (c->extended = sshbuf_new()) == NULL)
384 fatal("%s: sshbuf_new failed", __func__);
Damien Miller5144df92002-01-22 23:28:45 +1100385 c->ostate = CHAN_OUTPUT_OPEN;
386 c->istate = CHAN_INPUT_OPEN;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000387 channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, 0);
Damien Miller95def091999-11-25 00:26:21 +1100388 c->self = found;
389 c->type = type;
Damien Millerb38eff82000-04-01 11:09:21 +1000390 c->ctype = ctype;
Damien Millerbd483e72000-04-30 10:00:53 +1000391 c->local_window = window;
392 c->local_window_max = window;
Damien Millerbd483e72000-04-30 10:00:53 +1000393 c->local_maxpacket = maxpack;
Damien Millerb1ca8bb2003-05-14 13:45:42 +1000394 c->remote_name = xstrdup(remote_name);
Damien Millere1537f92010-01-26 13:26:22 +1100395 c->ctl_chan = -1;
Darren Tucker876045b2010-01-08 17:08:00 +1100396 c->delayed = 1; /* prevent call to channel_post handler */
Damien Millerb84886b2008-05-19 15:05:07 +1000397 TAILQ_INIT(&c->status_confirms);
Damien Miller95def091999-11-25 00:26:21 +1100398 debug("channel %d: new [%s]", found, remote_name);
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000399 return c;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000400}
Damien Miller6f83b8e2000-05-02 09:23:45 +1000401
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000402static void
403channel_find_maxfd(struct ssh_channels *sc)
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000404{
Darren Tuckerc7a6fc42004-08-13 21:18:00 +1000405 u_int i;
406 int max = 0;
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000407 Channel *c;
408
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000409 for (i = 0; i < sc->channels_alloc; i++) {
410 c = sc->channels[i];
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000411 if (c != NULL) {
deraadt@openbsd.org9136ec12016-09-12 01:22:38 +0000412 max = MAXIMUM(max, c->rfd);
413 max = MAXIMUM(max, c->wfd);
414 max = MAXIMUM(max, c->efd);
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000415 }
416 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000417 sc->channel_max_fd = max;
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000418}
419
420int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000421channel_close_fd(struct ssh *ssh, int *fdp)
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000422{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000423 struct ssh_channels *sc = ssh->chanctxt;
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000424 int ret = 0, fd = *fdp;
425
426 if (fd != -1) {
427 ret = close(fd);
428 *fdp = -1;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000429 if (fd == sc->channel_max_fd)
430 channel_find_maxfd(sc);
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000431 }
432 return ret;
433}
434
Damien Miller6f83b8e2000-05-02 09:23:45 +1000435/* Close all channel fd/socket. */
Ben Lindstrombba81212001-06-25 05:01:22 +0000436static void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000437channel_close_fds(struct ssh *ssh, Channel *c)
Damien Miller6f83b8e2000-05-02 09:23:45 +1000438{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000439 channel_close_fd(ssh, &c->sock);
440 channel_close_fd(ssh, &c->rfd);
441 channel_close_fd(ssh, &c->wfd);
442 channel_close_fd(ssh, &c->efd);
443}
444
445static void
446fwd_perm_clear(ForwardPermission *fp)
447{
448 free(fp->host_to_connect);
449 free(fp->listen_host);
450 free(fp->listen_path);
451 bzero(fp, sizeof(*fp));
452}
453
454enum { FWDPERM_USER, FWDPERM_ADMIN };
455
456static int
457fwd_perm_list_add(struct ssh *ssh, int which,
458 const char *host_to_connect, int port_to_connect,
459 const char *listen_host, const char *listen_path, int listen_port,
460 Channel *downstream)
461{
462 ForwardPermission **fpl;
463 u_int n, *nfpl;
464
465 switch (which) {
466 case FWDPERM_USER:
467 fpl = &ssh->chanctxt->permitted_opens;
468 nfpl = &ssh->chanctxt->num_permitted_opens;
469 break;
470 case FWDPERM_ADMIN:
471 fpl = &ssh->chanctxt->permitted_adm_opens;
472 nfpl = &ssh->chanctxt->num_adm_permitted_opens;
473 break;
474 default:
475 fatal("%s: invalid list %d", __func__, which);
476 }
477
478 if (*nfpl >= INT_MAX)
479 fatal("%s: overflow", __func__);
480
481 *fpl = xrecallocarray(*fpl, *nfpl, *nfpl + 1, sizeof(**fpl));
482 n = (*nfpl)++;
483#define MAYBE_DUP(s) ((s == NULL) ? NULL : xstrdup(s))
484 (*fpl)[n].host_to_connect = MAYBE_DUP(host_to_connect);
485 (*fpl)[n].port_to_connect = port_to_connect;
486 (*fpl)[n].listen_host = MAYBE_DUP(listen_host);
487 (*fpl)[n].listen_path = MAYBE_DUP(listen_path);
488 (*fpl)[n].listen_port = listen_port;
489 (*fpl)[n].downstream = downstream;
490#undef MAYBE_DUP
491 return (int)n;
492}
493
494static void
495mux_remove_remote_forwardings(struct ssh *ssh, Channel *c)
496{
497 struct ssh_channels *sc = ssh->chanctxt;
498 ForwardPermission *fp;
499 int r;
500 u_int i;
501
502 for (i = 0; i < sc->num_permitted_opens; i++) {
503 fp = &sc->permitted_opens[i];
504 if (fp->downstream != c)
505 continue;
506
507 /* cancel on the server, since mux client is gone */
508 debug("channel %d: cleanup remote forward for %s:%u",
509 c->self, fp->listen_host, fp->listen_port);
510 if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
511 (r = sshpkt_put_cstring(ssh,
512 "cancel-tcpip-forward")) != 0 ||
513 (r = sshpkt_put_u8(ssh, 0)) != 0 ||
514 (r = sshpkt_put_cstring(ssh,
515 channel_rfwd_bind_host(fp->listen_host))) != 0 ||
516 (r = sshpkt_put_u32(ssh, fp->listen_port)) != 0 ||
517 (r = sshpkt_send(ssh)) != 0) {
518 fatal("%s: channel %i: %s", __func__,
519 c->self, ssh_err(r));
520 }
521 fwd_perm_clear(fp); /* unregister */
522 }
Damien Miller6f83b8e2000-05-02 09:23:45 +1000523}
524
525/* Free the channel and close its fd/socket. */
Damien Miller4af51302000-04-16 11:18:38 +1000526void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000527channel_free(struct ssh *ssh, Channel *c)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000528{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000529 struct ssh_channels *sc = ssh->chanctxt;
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000530 char *s;
Darren Tuckerc7a6fc42004-08-13 21:18:00 +1000531 u_int i, n;
markus@openbsd.org8d057842016-09-30 09:19:13 +0000532 Channel *other;
Damien Millerb84886b2008-05-19 15:05:07 +1000533 struct channel_confirm *cc;
Ben Lindstromc0dee1a2001-06-05 20:52:50 +0000534
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000535 for (n = 0, i = 0; i < sc->channels_alloc; i++) {
536 if ((other = sc->channels[i]) == NULL)
537 continue;
538 n++;
539 /* detach from mux client and prepare for closing */
540 if (c->type == SSH_CHANNEL_MUX_CLIENT &&
541 other->type == SSH_CHANNEL_MUX_PROXY &&
542 other->mux_ctx == c) {
543 other->mux_ctx = NULL;
544 other->type = SSH_CHANNEL_OPEN;
545 other->istate = CHAN_INPUT_CLOSED;
546 other->ostate = CHAN_OUTPUT_CLOSED;
markus@openbsd.org8d057842016-09-30 09:19:13 +0000547 }
548 }
Darren Tuckerc7a6fc42004-08-13 21:18:00 +1000549 debug("channel %d: free: %s, nchannels %u", c->self,
Ben Lindstromc0dee1a2001-06-05 20:52:50 +0000550 c->remote_name ? c->remote_name : "???", n);
Ben Lindstrom6c3ae2b2000-12-30 03:25:14 +0000551
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000552 if (c->type == SSH_CHANNEL_MUX_CLIENT)
553 mux_remove_remote_forwardings(ssh, c);
markus@openbsd.org8d057842016-09-30 09:19:13 +0000554
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000555 s = channel_open_message(ssh);
Damien Millerfbdeece2003-09-02 22:52:31 +1000556 debug3("channel %d: status: %s", c->self, s);
Darren Tuckera627d422013-06-02 07:31:17 +1000557 free(s);
Ben Lindstrom6c3ae2b2000-12-30 03:25:14 +0000558
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000559 channel_close_fds(ssh, c);
560 sshbuf_free(c->input);
561 sshbuf_free(c->output);
562 sshbuf_free(c->extended);
563 c->input = c->output = c->extended = NULL;
Darren Tuckera627d422013-06-02 07:31:17 +1000564 free(c->remote_name);
565 c->remote_name = NULL;
566 free(c->path);
567 c->path = NULL;
568 free(c->listening_addr);
569 c->listening_addr = NULL;
Damien Millerb84886b2008-05-19 15:05:07 +1000570 while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
571 if (cc->abandon_cb != NULL)
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000572 cc->abandon_cb(ssh, c, cc->ctx);
Damien Millerb84886b2008-05-19 15:05:07 +1000573 TAILQ_REMOVE(&c->status_confirms, cc, entry);
Damien Miller1d2c4562014-02-04 11:18:20 +1100574 explicit_bzero(cc, sizeof(*cc));
Darren Tuckera627d422013-06-02 07:31:17 +1000575 free(cc);
Damien Millerb84886b2008-05-19 15:05:07 +1000576 }
Darren Tucker84c56f52008-06-13 04:55:46 +1000577 if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000578 c->filter_cleanup(ssh, c->self, c->filter_ctx);
579 sc->channels[c->self] = NULL;
millert@openbsd.org3e8d1852017-09-19 12:10:30 +0000580 explicit_bzero(c, sizeof(*c));
Darren Tuckera627d422013-06-02 07:31:17 +1000581 free(c);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000582}
583
Ben Lindstrome9c99912001-06-09 00:41:05 +0000584void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000585channel_free_all(struct ssh *ssh)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000586{
Darren Tuckerc7a6fc42004-08-13 21:18:00 +1000587 u_int i;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000588
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000589 for (i = 0; i < ssh->chanctxt->channels_alloc; i++)
590 if (ssh->chanctxt->channels[i] != NULL)
591 channel_free(ssh, ssh->chanctxt->channels[i]);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000592}
593
594/*
595 * Closes the sockets/fds of all channels. This is used to close extra file
596 * descriptors after a fork.
597 */
Ben Lindstrome9c99912001-06-09 00:41:05 +0000598void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000599channel_close_all(struct ssh *ssh)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000600{
Darren Tuckerc7a6fc42004-08-13 21:18:00 +1000601 u_int i;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000602
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000603 for (i = 0; i < ssh->chanctxt->channels_alloc; i++)
604 if (ssh->chanctxt->channels[i] != NULL)
605 channel_close_fds(ssh, ssh->chanctxt->channels[i]);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000606}
607
608/*
Ben Lindstrom809744e2001-07-04 05:26:06 +0000609 * Stop listening to channels.
610 */
Ben Lindstrom809744e2001-07-04 05:26:06 +0000611void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000612channel_stop_listening(struct ssh *ssh)
Ben Lindstrom809744e2001-07-04 05:26:06 +0000613{
Darren Tuckerc7a6fc42004-08-13 21:18:00 +1000614 u_int i;
Ben Lindstrom809744e2001-07-04 05:26:06 +0000615 Channel *c;
616
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000617 for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
618 c = ssh->chanctxt->channels[i];
Ben Lindstrom809744e2001-07-04 05:26:06 +0000619 if (c != NULL) {
620 switch (c->type) {
621 case SSH_CHANNEL_AUTH_SOCKET:
622 case SSH_CHANNEL_PORT_LISTENER:
623 case SSH_CHANNEL_RPORT_LISTENER:
624 case SSH_CHANNEL_X11_LISTENER:
Damien Miller7acefbb2014-07-18 14:11:24 +1000625 case SSH_CHANNEL_UNIX_LISTENER:
626 case SSH_CHANNEL_RUNIX_LISTENER:
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000627 channel_close_fd(ssh, &c->sock);
628 channel_free(ssh, c);
Ben Lindstrom809744e2001-07-04 05:26:06 +0000629 break;
630 }
631 }
632 }
633}
634
635/*
Ben Lindstrome9c99912001-06-09 00:41:05 +0000636 * Returns true if no channel has too much buffered data, and false if one or
637 * more channel is overfull.
638 */
Ben Lindstrome9c99912001-06-09 00:41:05 +0000639int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000640channel_not_very_much_buffered_data(struct ssh *ssh)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000641{
642 u_int i;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000643 u_int maxsize = ssh_packet_get_maxsize(ssh);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000644 Channel *c;
645
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000646 for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
647 c = ssh->chanctxt->channels[i];
648 if (c == NULL || c->type != SSH_CHANNEL_OPEN)
649 continue;
650 if (sshbuf_len(c->output) > maxsize) {
651 debug2("channel %d: big output buffer %zu > %u",
652 c->self, sshbuf_len(c->output), maxsize);
653 return 0;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000654 }
655 }
656 return 1;
657}
658
659/* Returns true if any channel is still open. */
Ben Lindstrome9c99912001-06-09 00:41:05 +0000660int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000661channel_still_open(struct ssh *ssh)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000662{
Darren Tuckerc7a6fc42004-08-13 21:18:00 +1000663 u_int i;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000664 Channel *c;
665
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000666 for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
667 c = ssh->chanctxt->channels[i];
Ben Lindstrome9c99912001-06-09 00:41:05 +0000668 if (c == NULL)
669 continue;
670 switch (c->type) {
671 case SSH_CHANNEL_X11_LISTENER:
672 case SSH_CHANNEL_PORT_LISTENER:
673 case SSH_CHANNEL_RPORT_LISTENER:
Damien Millere1537f92010-01-26 13:26:22 +1100674 case SSH_CHANNEL_MUX_LISTENER:
Ben Lindstrome9c99912001-06-09 00:41:05 +0000675 case SSH_CHANNEL_CLOSED:
676 case SSH_CHANNEL_AUTH_SOCKET:
677 case SSH_CHANNEL_DYNAMIC:
markus@openbsd.org609d7a62017-09-21 19:16:53 +0000678 case SSH_CHANNEL_RDYNAMIC_OPEN:
Ben Lindstrome9c99912001-06-09 00:41:05 +0000679 case SSH_CHANNEL_CONNECTING:
680 case SSH_CHANNEL_ZOMBIE:
Damien Miller36187092013-06-10 13:07:11 +1000681 case SSH_CHANNEL_ABANDONED:
Damien Miller7acefbb2014-07-18 14:11:24 +1000682 case SSH_CHANNEL_UNIX_LISTENER:
683 case SSH_CHANNEL_RUNIX_LISTENER:
Ben Lindstrome9c99912001-06-09 00:41:05 +0000684 continue;
685 case SSH_CHANNEL_LARVAL:
Ben Lindstrome9c99912001-06-09 00:41:05 +0000686 continue;
687 case SSH_CHANNEL_OPENING:
688 case SSH_CHANNEL_OPEN:
markus@openbsd.org609d7a62017-09-21 19:16:53 +0000689 case SSH_CHANNEL_RDYNAMIC_FINISH:
Ben Lindstrome9c99912001-06-09 00:41:05 +0000690 case SSH_CHANNEL_X11_OPEN:
Damien Millere1537f92010-01-26 13:26:22 +1100691 case SSH_CHANNEL_MUX_CLIENT:
markus@openbsd.org8d057842016-09-30 09:19:13 +0000692 case SSH_CHANNEL_MUX_PROXY:
Ben Lindstrome9c99912001-06-09 00:41:05 +0000693 return 1;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000694 default:
djm@openbsd.org97f4d302017-04-30 23:13:25 +0000695 fatal("%s: bad channel type %d", __func__, c->type);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000696 /* NOTREACHED */
697 }
698 }
699 return 0;
700}
701
702/* Returns the id of an open channel suitable for keepaliving */
Ben Lindstrome9c99912001-06-09 00:41:05 +0000703int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000704channel_find_open(struct ssh *ssh)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000705{
Darren Tuckerc7a6fc42004-08-13 21:18:00 +1000706 u_int i;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000707 Channel *c;
708
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000709 for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
710 c = ssh->chanctxt->channels[i];
djm@openbsd.org9f532292017-09-12 06:35:31 +0000711 if (c == NULL || !c->have_remote_id)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000712 continue;
713 switch (c->type) {
714 case SSH_CHANNEL_CLOSED:
715 case SSH_CHANNEL_DYNAMIC:
markus@openbsd.org609d7a62017-09-21 19:16:53 +0000716 case SSH_CHANNEL_RDYNAMIC_OPEN:
717 case SSH_CHANNEL_RDYNAMIC_FINISH:
Ben Lindstrome9c99912001-06-09 00:41:05 +0000718 case SSH_CHANNEL_X11_LISTENER:
719 case SSH_CHANNEL_PORT_LISTENER:
720 case SSH_CHANNEL_RPORT_LISTENER:
Damien Millere1537f92010-01-26 13:26:22 +1100721 case SSH_CHANNEL_MUX_LISTENER:
722 case SSH_CHANNEL_MUX_CLIENT:
markus@openbsd.org8d057842016-09-30 09:19:13 +0000723 case SSH_CHANNEL_MUX_PROXY:
Ben Lindstrome9c99912001-06-09 00:41:05 +0000724 case SSH_CHANNEL_OPENING:
725 case SSH_CHANNEL_CONNECTING:
726 case SSH_CHANNEL_ZOMBIE:
Damien Miller36187092013-06-10 13:07:11 +1000727 case SSH_CHANNEL_ABANDONED:
Damien Miller7acefbb2014-07-18 14:11:24 +1000728 case SSH_CHANNEL_UNIX_LISTENER:
729 case SSH_CHANNEL_RUNIX_LISTENER:
Ben Lindstrome9c99912001-06-09 00:41:05 +0000730 continue;
731 case SSH_CHANNEL_LARVAL:
732 case SSH_CHANNEL_AUTH_SOCKET:
733 case SSH_CHANNEL_OPEN:
734 case SSH_CHANNEL_X11_OPEN:
735 return i;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000736 default:
djm@openbsd.org97f4d302017-04-30 23:13:25 +0000737 fatal("%s: bad channel type %d", __func__, c->type);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000738 /* NOTREACHED */
739 }
740 }
741 return -1;
742}
743
Ben Lindstrome9c99912001-06-09 00:41:05 +0000744/*
745 * Returns a message describing the currently open forwarded connections,
746 * suitable for sending to the client. The message contains crlf pairs for
747 * newlines.
748 */
Ben Lindstrome9c99912001-06-09 00:41:05 +0000749char *
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000750channel_open_message(struct ssh *ssh)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000751{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000752 struct sshbuf *buf;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000753 Channel *c;
Darren Tuckerc7a6fc42004-08-13 21:18:00 +1000754 u_int i;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000755 int r;
756 char *ret;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000757
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000758 if ((buf = sshbuf_new()) == NULL)
759 fatal("%s: sshbuf_new", __func__);
760 if ((r = sshbuf_putf(buf,
761 "The following connections are open:\r\n")) != 0)
762 fatal("%s: sshbuf_putf: %s", __func__, ssh_err(r));
763 for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
764 c = ssh->chanctxt->channels[i];
Ben Lindstrome9c99912001-06-09 00:41:05 +0000765 if (c == NULL)
766 continue;
767 switch (c->type) {
768 case SSH_CHANNEL_X11_LISTENER:
769 case SSH_CHANNEL_PORT_LISTENER:
770 case SSH_CHANNEL_RPORT_LISTENER:
771 case SSH_CHANNEL_CLOSED:
772 case SSH_CHANNEL_AUTH_SOCKET:
773 case SSH_CHANNEL_ZOMBIE:
Damien Miller36187092013-06-10 13:07:11 +1000774 case SSH_CHANNEL_ABANDONED:
Damien Millere1537f92010-01-26 13:26:22 +1100775 case SSH_CHANNEL_MUX_LISTENER:
Damien Miller7acefbb2014-07-18 14:11:24 +1000776 case SSH_CHANNEL_UNIX_LISTENER:
777 case SSH_CHANNEL_RUNIX_LISTENER:
Ben Lindstrome9c99912001-06-09 00:41:05 +0000778 continue;
779 case SSH_CHANNEL_LARVAL:
780 case SSH_CHANNEL_OPENING:
781 case SSH_CHANNEL_CONNECTING:
782 case SSH_CHANNEL_DYNAMIC:
markus@openbsd.org609d7a62017-09-21 19:16:53 +0000783 case SSH_CHANNEL_RDYNAMIC_OPEN:
784 case SSH_CHANNEL_RDYNAMIC_FINISH:
Ben Lindstrome9c99912001-06-09 00:41:05 +0000785 case SSH_CHANNEL_OPEN:
786 case SSH_CHANNEL_X11_OPEN:
markus@openbsd.org8d057842016-09-30 09:19:13 +0000787 case SSH_CHANNEL_MUX_PROXY:
788 case SSH_CHANNEL_MUX_CLIENT:
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000789 if ((r = sshbuf_putf(buf, " #%d %.300s "
djm@openbsd.org9f532292017-09-12 06:35:31 +0000790 "(t%d %s%u i%u/%zu o%u/%zu fd %d/%d cc %d)\r\n",
Ben Lindstrome9c99912001-06-09 00:41:05 +0000791 c->self, c->remote_name,
djm@openbsd.org9f532292017-09-12 06:35:31 +0000792 c->type,
793 c->have_remote_id ? "r" : "nr", c->remote_id,
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000794 c->istate, sshbuf_len(c->input),
795 c->ostate, sshbuf_len(c->output),
796 c->rfd, c->wfd, c->ctl_chan)) != 0)
797 fatal("%s: sshbuf_putf: %s",
798 __func__, ssh_err(r));
Ben Lindstrome9c99912001-06-09 00:41:05 +0000799 continue;
800 default:
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000801 fatal("%s: bad channel type %d", __func__, c->type);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000802 /* NOTREACHED */
803 }
804 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000805 if ((ret = sshbuf_dup_string(buf)) == NULL)
806 fatal("%s: sshbuf_dup_string", __func__);
807 sshbuf_free(buf);
808 return ret;
809}
810
811static void
812open_preamble(struct ssh *ssh, const char *where, Channel *c, const char *type)
813{
814 int r;
815
816 if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN)) != 0 ||
817 (r = sshpkt_put_cstring(ssh, type)) != 0 ||
818 (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
819 (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
820 (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
821 fatal("%s: channel %i: open: %s", where, c->self, ssh_err(r));
822 }
Ben Lindstrome9c99912001-06-09 00:41:05 +0000823}
824
825void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000826channel_send_open(struct ssh *ssh, int id)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000827{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000828 Channel *c = channel_lookup(ssh, id);
829 int r;
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000830
Ben Lindstrome9c99912001-06-09 00:41:05 +0000831 if (c == NULL) {
Damien Miller996acd22003-04-09 20:59:48 +1000832 logit("channel_send_open: %d: bad id", id);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000833 return;
834 }
Ben Lindstrom1d568f92002-12-23 02:44:36 +0000835 debug2("channel %d: send open", id);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000836 open_preamble(ssh, __func__, c, c->ctype);
837 if ((r = sshpkt_send(ssh)) != 0)
838 fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
Ben Lindstrome9c99912001-06-09 00:41:05 +0000839}
840
841void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000842channel_request_start(struct ssh *ssh, int id, char *service, int wantconfirm)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000843{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000844 Channel *c = channel_lookup(ssh, id);
845 int r;
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000846
Ben Lindstrome9c99912001-06-09 00:41:05 +0000847 if (c == NULL) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000848 logit("%s: %d: unknown channel id", __func__, id);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000849 return;
850 }
djm@openbsd.org9f532292017-09-12 06:35:31 +0000851 if (!c->have_remote_id)
852 fatal(":%s: channel %d: no remote id", __func__, c->self);
853
Damien Miller0e220db2004-06-15 10:34:08 +1000854 debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000855 if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_REQUEST)) != 0 ||
856 (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
857 (r = sshpkt_put_cstring(ssh, service)) != 0 ||
858 (r = sshpkt_put_u8(ssh, wantconfirm)) != 0) {
859 fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
860 }
Ben Lindstrome9c99912001-06-09 00:41:05 +0000861}
Damien Miller4f7becb2006-03-26 14:10:14 +1100862
Ben Lindstrome9c99912001-06-09 00:41:05 +0000863void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000864channel_register_status_confirm(struct ssh *ssh, int id,
865 channel_confirm_cb *cb, channel_confirm_abandon_cb *abandon_cb, void *ctx)
Damien Millerb84886b2008-05-19 15:05:07 +1000866{
867 struct channel_confirm *cc;
868 Channel *c;
869
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000870 if ((c = channel_lookup(ssh, id)) == NULL)
871 fatal("%s: %d: bad id", __func__, id);
Damien Millerb84886b2008-05-19 15:05:07 +1000872
Damien Miller6c81fee2013-11-08 12:19:55 +1100873 cc = xcalloc(1, sizeof(*cc));
Damien Millerb84886b2008-05-19 15:05:07 +1000874 cc->cb = cb;
875 cc->abandon_cb = abandon_cb;
876 cc->ctx = ctx;
877 TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
878}
879
880void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000881channel_register_open_confirm(struct ssh *ssh, int id,
882 channel_open_fn *fn, void *ctx)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000883{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000884 Channel *c = channel_lookup(ssh, id);
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000885
Ben Lindstrome9c99912001-06-09 00:41:05 +0000886 if (c == NULL) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000887 logit("%s: %d: bad id", __func__, id);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000888 return;
889 }
Damien Millerb84886b2008-05-19 15:05:07 +1000890 c->open_confirm = fn;
891 c->open_confirm_ctx = ctx;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000892}
Damien Miller4f7becb2006-03-26 14:10:14 +1100893
Ben Lindstrome9c99912001-06-09 00:41:05 +0000894void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000895channel_register_cleanup(struct ssh *ssh, int id,
896 channel_callback_fn *fn, int do_close)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000897{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000898 Channel *c = channel_by_id(ssh, id);
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000899
Ben Lindstrome9c99912001-06-09 00:41:05 +0000900 if (c == NULL) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000901 logit("%s: %d: bad id", __func__, id);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000902 return;
903 }
Ben Lindstrom809744e2001-07-04 05:26:06 +0000904 c->detach_user = fn;
Damien Miller39eda6e2005-11-05 14:52:50 +1100905 c->detach_close = do_close;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000906}
Damien Miller4f7becb2006-03-26 14:10:14 +1100907
Ben Lindstrome9c99912001-06-09 00:41:05 +0000908void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000909channel_cancel_cleanup(struct ssh *ssh, int id)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000910{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000911 Channel *c = channel_by_id(ssh, id);
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000912
Ben Lindstrome9c99912001-06-09 00:41:05 +0000913 if (c == NULL) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000914 logit("%s: %d: bad id", __func__, id);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000915 return;
916 }
Ben Lindstrom809744e2001-07-04 05:26:06 +0000917 c->detach_user = NULL;
Damien Miller39eda6e2005-11-05 14:52:50 +1100918 c->detach_close = 0;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000919}
Damien Miller4f7becb2006-03-26 14:10:14 +1100920
Ben Lindstrome9c99912001-06-09 00:41:05 +0000921void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000922channel_register_filter(struct ssh *ssh, int id, channel_infilter_fn *ifn,
Darren Tucker84c56f52008-06-13 04:55:46 +1000923 channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000924{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000925 Channel *c = channel_lookup(ssh, id);
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000926
Ben Lindstrome9c99912001-06-09 00:41:05 +0000927 if (c == NULL) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000928 logit("%s: %d: bad id", __func__, id);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000929 return;
930 }
Damien Miller077b2382005-12-31 16:22:32 +1100931 c->input_filter = ifn;
932 c->output_filter = ofn;
Darren Tucker2fb66ca2008-06-13 04:49:33 +1000933 c->filter_ctx = ctx;
Darren Tucker84c56f52008-06-13 04:55:46 +1000934 c->filter_cleanup = cfn;
Ben Lindstrome9c99912001-06-09 00:41:05 +0000935}
936
937void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000938channel_set_fds(struct ssh *ssh, int id, int rfd, int wfd, int efd,
Darren Tuckered3cdc02008-06-16 23:29:18 +1000939 int extusage, int nonblock, int is_tty, u_int window_max)
Ben Lindstrome9c99912001-06-09 00:41:05 +0000940{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000941 Channel *c = channel_lookup(ssh, id);
942 int r;
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +0000943
Ben Lindstrome9c99912001-06-09 00:41:05 +0000944 if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
945 fatal("channel_activate for non-larval channel %d.", id);
djm@openbsd.org9f532292017-09-12 06:35:31 +0000946 if (!c->have_remote_id)
947 fatal(":%s: channel %d: no remote id", __func__, c->self);
948
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000949 channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, is_tty);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000950 c->type = SSH_CHANNEL_OPEN;
Damien Miller2aa0c192002-02-19 15:20:08 +1100951 c->local_window = c->local_window_max = window_max;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000952
953 if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
954 (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
955 (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
956 (r = sshpkt_send(ssh)) != 0)
957 fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
Ben Lindstrome9c99912001-06-09 00:41:05 +0000958}
959
Ben Lindstrombba81212001-06-25 05:01:22 +0000960static void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000961channel_pre_listener(struct ssh *ssh, Channel *c,
962 fd_set *readset, fd_set *writeset)
Damien Millerb38eff82000-04-01 11:09:21 +1000963{
964 FD_SET(c->sock, readset);
965}
966
Ben Lindstrombba81212001-06-25 05:01:22 +0000967static void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000968channel_pre_connecting(struct ssh *ssh, Channel *c,
969 fd_set *readset, fd_set *writeset)
Ben Lindstrom7ad97102000-12-06 01:42:49 +0000970{
971 debug3("channel %d: waiting for connection", c->self);
972 FD_SET(c->sock, writeset);
973}
974
Ben Lindstrombba81212001-06-25 05:01:22 +0000975static void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000976channel_pre_open(struct ssh *ssh, Channel *c,
977 fd_set *readset, fd_set *writeset)
Damien Millerb38eff82000-04-01 11:09:21 +1000978{
Damien Miller33b13562000-04-04 14:38:59 +1000979 if (c->istate == CHAN_INPUT_OPEN &&
djm@openbsd.org97f4d302017-04-30 23:13:25 +0000980 c->remote_window > 0 &&
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000981 sshbuf_len(c->input) < c->remote_window &&
982 sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
Damien Miller33b13562000-04-04 14:38:59 +1000983 FD_SET(c->rfd, readset);
984 if (c->ostate == CHAN_OUTPUT_OPEN ||
985 c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000986 if (sshbuf_len(c->output) > 0) {
Damien Miller33b13562000-04-04 14:38:59 +1000987 FD_SET(c->wfd, writeset);
988 } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
Ben Lindstromcf159442002-03-26 03:26:24 +0000989 if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000990 debug2("channel %d: "
991 "obuf_empty delayed efd %d/(%zu)", c->self,
992 c->efd, sshbuf_len(c->extended));
Ben Lindstromcf159442002-03-26 03:26:24 +0000993 else
djm@openbsd.orgdbee4112017-09-12 06:32:07 +0000994 chan_obuf_empty(ssh, c);
Damien Miller33b13562000-04-04 14:38:59 +1000995 }
996 }
997 /** XXX check close conditions, too */
djm@openbsd.org97f4d302017-04-30 23:13:25 +0000998 if (c->efd != -1 && !(c->istate == CHAN_INPUT_CLOSED &&
999 c->ostate == CHAN_OUTPUT_CLOSED)) {
Damien Miller33b13562000-04-04 14:38:59 +10001000 if (c->extended_usage == CHAN_EXTENDED_WRITE &&
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001001 sshbuf_len(c->extended) > 0)
Damien Miller33b13562000-04-04 14:38:59 +10001002 FD_SET(c->efd, writeset);
Damien Miller8853ca52010-06-26 10:00:14 +10001003 else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
1004 (c->extended_usage == CHAN_EXTENDED_READ ||
1005 c->extended_usage == CHAN_EXTENDED_IGNORE) &&
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001006 sshbuf_len(c->extended) < c->remote_window)
Damien Miller33b13562000-04-04 14:38:59 +10001007 FD_SET(c->efd, readset);
1008 }
Damien Miller0e220db2004-06-15 10:34:08 +10001009 /* XXX: What about efd? races? */
Damien Miller33b13562000-04-04 14:38:59 +10001010}
1011
Damien Millerb38eff82000-04-01 11:09:21 +10001012/*
1013 * This is a special state for X11 authentication spoofing. An opened X11
1014 * connection (when authentication spoofing is being done) remains in this
1015 * state until the first packet has been completely read. The authentication
1016 * data in that packet is then substituted by the real data if it matches the
1017 * fake data, and the channel is put into normal mode.
Damien Millerbd483e72000-04-30 10:00:53 +10001018 * XXX All this happens at the client side.
Ben Lindstrome9c99912001-06-09 00:41:05 +00001019 * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
Damien Millerb38eff82000-04-01 11:09:21 +10001020 */
Ben Lindstrombba81212001-06-25 05:01:22 +00001021static int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001022x11_open_helper(struct ssh *ssh, struct sshbuf *b)
Damien Millerb38eff82000-04-01 11:09:21 +10001023{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001024 struct ssh_channels *sc = ssh->chanctxt;
Ben Lindstrom46c16222000-12-22 01:43:59 +00001025 u_char *ucp;
1026 u_int proto_len, data_len;
Damien Millerb38eff82000-04-01 11:09:21 +10001027
djm@openbsd.org1bf477d2015-07-01 02:26:31 +00001028 /* Is this being called after the refusal deadline? */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001029 if (sc->x11_refuse_time != 0 &&
1030 (u_int)monotime() >= sc->x11_refuse_time) {
djm@openbsd.org1bf477d2015-07-01 02:26:31 +00001031 verbose("Rejected X11 connection after ForwardX11Timeout "
1032 "expired");
1033 return -1;
1034 }
1035
Damien Millerb38eff82000-04-01 11:09:21 +10001036 /* Check if the fixed size part of the packet is in buffer. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001037 if (sshbuf_len(b) < 12)
Damien Millerb38eff82000-04-01 11:09:21 +10001038 return 0;
1039
1040 /* Parse the lengths of variable-length fields. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001041 ucp = sshbuf_mutable_ptr(b);
Damien Millerb38eff82000-04-01 11:09:21 +10001042 if (ucp[0] == 0x42) { /* Byte order MSB first. */
1043 proto_len = 256 * ucp[6] + ucp[7];
1044 data_len = 256 * ucp[8] + ucp[9];
1045 } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
1046 proto_len = ucp[6] + 256 * ucp[7];
1047 data_len = ucp[8] + 256 * ucp[9];
1048 } else {
Damien Millerfbdeece2003-09-02 22:52:31 +10001049 debug2("Initial X11 packet contains bad byte order byte: 0x%x",
Damien Miller9f0f5c62001-12-21 14:45:46 +11001050 ucp[0]);
Damien Millerb38eff82000-04-01 11:09:21 +10001051 return -1;
1052 }
1053
1054 /* Check if the whole packet is in buffer. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001055 if (sshbuf_len(b) <
Damien Millerb38eff82000-04-01 11:09:21 +10001056 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
1057 return 0;
1058
1059 /* Check if authentication protocol matches. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001060 if (proto_len != strlen(sc->x11_saved_proto) ||
1061 memcmp(ucp + 12, sc->x11_saved_proto, proto_len) != 0) {
Damien Millerfbdeece2003-09-02 22:52:31 +10001062 debug2("X11 connection uses different authentication protocol.");
Damien Millerb38eff82000-04-01 11:09:21 +10001063 return -1;
1064 }
1065 /* Check if authentication data matches our fake data. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001066 if (data_len != sc->x11_fake_data_len ||
Damien Millerea1651c2010-07-16 13:58:37 +10001067 timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001068 sc->x11_fake_data, sc->x11_fake_data_len) != 0) {
Damien Millerfbdeece2003-09-02 22:52:31 +10001069 debug2("X11 auth data does not match fake data.");
Damien Millerb38eff82000-04-01 11:09:21 +10001070 return -1;
1071 }
1072 /* Check fake data length */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001073 if (sc->x11_fake_data_len != sc->x11_saved_data_len) {
Damien Millerb38eff82000-04-01 11:09:21 +10001074 error("X11 fake_data_len %d != saved_data_len %d",
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001075 sc->x11_fake_data_len, sc->x11_saved_data_len);
Damien Millerb38eff82000-04-01 11:09:21 +10001076 return -1;
1077 }
1078 /*
1079 * Received authentication protocol and data match
1080 * our fake data. Substitute the fake data with real
1081 * data.
1082 */
1083 memcpy(ucp + 12 + ((proto_len + 3) & ~3),
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001084 sc->x11_saved_data, sc->x11_saved_data_len);
Damien Millerb38eff82000-04-01 11:09:21 +10001085 return 1;
1086}
1087
Ben Lindstrombba81212001-06-25 05:01:22 +00001088static void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001089channel_pre_x11_open(struct ssh *ssh, Channel *c,
1090 fd_set *readset, fd_set *writeset)
Damien Millerb38eff82000-04-01 11:09:21 +10001091{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001092 int ret = x11_open_helper(ssh, c->output);
Ben Lindstrom944c4f02001-09-18 05:51:13 +00001093
1094 /* c->force_drain = 1; */
1095
Damien Millerb38eff82000-04-01 11:09:21 +10001096 if (ret == 1) {
1097 c->type = SSH_CHANNEL_OPEN;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001098 channel_pre_open(ssh, c, readset, writeset);
Damien Millerb38eff82000-04-01 11:09:21 +10001099 } else if (ret == -1) {
Damien Miller996acd22003-04-09 20:59:48 +10001100 logit("X11 connection rejected because of wrong authentication.");
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001101 debug2("X11 rejected %d i%d/o%d",
1102 c->self, c->istate, c->ostate);
1103 chan_read_failed(ssh, c);
1104 sshbuf_reset(c->input);
1105 chan_ibuf_empty(ssh, c);
1106 sshbuf_reset(c->output);
1107 chan_write_failed(ssh, c);
Damien Millerfbdeece2003-09-02 22:52:31 +10001108 debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
Damien Millerb38eff82000-04-01 11:09:21 +10001109 }
1110}
1111
Damien Millere1537f92010-01-26 13:26:22 +11001112static void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001113channel_pre_mux_client(struct ssh *ssh,
1114 Channel *c, fd_set *readset, fd_set *writeset)
Damien Millere1537f92010-01-26 13:26:22 +11001115{
Damien Millerd530f5f2010-05-21 14:57:10 +10001116 if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001117 sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
Damien Millere1537f92010-01-26 13:26:22 +11001118 FD_SET(c->rfd, readset);
1119 if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1120 /* clear buffer immediately (discard any partial packet) */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001121 sshbuf_reset(c->input);
1122 chan_ibuf_empty(ssh, c);
Damien Millere1537f92010-01-26 13:26:22 +11001123 /* Start output drain. XXX just kill chan? */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001124 chan_rcvd_oclose(ssh, c);
Damien Millere1537f92010-01-26 13:26:22 +11001125 }
1126 if (c->ostate == CHAN_OUTPUT_OPEN ||
1127 c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001128 if (sshbuf_len(c->output) > 0)
Damien Millere1537f92010-01-26 13:26:22 +11001129 FD_SET(c->wfd, writeset);
1130 else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001131 chan_obuf_empty(ssh, c);
Damien Millere1537f92010-01-26 13:26:22 +11001132 }
1133}
1134
Ben Lindstromb3921512001-04-11 15:57:50 +00001135/* try to decode a socks4 header */
Ben Lindstrombba81212001-06-25 05:01:22 +00001136static int
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001137channel_decode_socks4(Channel *c, struct sshbuf *input, struct sshbuf *output)
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001138{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001139 const u_char *p;
1140 char *host;
Damien Miller1781f532009-01-28 16:24:41 +11001141 u_int len, have, i, found, need;
Damien Miller9f0f5c62001-12-21 14:45:46 +11001142 char username[256];
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001143 struct {
1144 u_int8_t version;
1145 u_int8_t command;
1146 u_int16_t dest_port;
Ben Lindstromb3921512001-04-11 15:57:50 +00001147 struct in_addr dest_addr;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001148 } s4_req, s4_rsp;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001149 int r;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001150
Ben Lindstromb3921512001-04-11 15:57:50 +00001151 debug2("channel %d: decode socks4", c->self);
Ben Lindstrom2b261b92001-04-17 18:14:34 +00001152
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001153 have = sshbuf_len(input);
Ben Lindstrom2b261b92001-04-17 18:14:34 +00001154 len = sizeof(s4_req);
1155 if (have < len)
1156 return 0;
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001157 p = sshbuf_ptr(input);
Damien Miller1781f532009-01-28 16:24:41 +11001158
1159 need = 1;
1160 /* SOCKS4A uses an invalid IP address 0.0.0.x */
1161 if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1162 debug2("channel %d: socks4a request", c->self);
1163 /* ... and needs an extra string (the hostname) */
1164 need = 2;
1165 }
1166 /* Check for terminating NUL on the string(s) */
Ben Lindstrom2b261b92001-04-17 18:14:34 +00001167 for (found = 0, i = len; i < have; i++) {
1168 if (p[i] == '\0') {
Damien Miller1781f532009-01-28 16:24:41 +11001169 found++;
1170 if (found == need)
1171 break;
Ben Lindstrom2b261b92001-04-17 18:14:34 +00001172 }
1173 if (i > 1024) {
1174 /* the peer is probably sending garbage */
1175 debug("channel %d: decode socks4: too long",
1176 c->self);
1177 return -1;
1178 }
1179 }
Damien Miller1781f532009-01-28 16:24:41 +11001180 if (found < need)
Ben Lindstrom2b261b92001-04-17 18:14:34 +00001181 return 0;
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001182 if ((r = sshbuf_get(input, &s4_req.version, 1)) != 0 ||
1183 (r = sshbuf_get(input, &s4_req.command, 1)) != 0 ||
1184 (r = sshbuf_get(input, &s4_req.dest_port, 2)) != 0 ||
1185 (r = sshbuf_get(input, &s4_req.dest_addr, 4)) != 0) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001186 debug("channels %d: decode socks4: %s", c->self, ssh_err(r));
1187 return -1;
1188 }
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001189 have = sshbuf_len(input);
1190 p = sshbuf_ptr(input);
djm@openbsd.orgc04e9792017-05-31 00:43:04 +00001191 if (memchr(p, '\0', have) == NULL) {
1192 error("channel %d: decode socks4: user not nul terminated",
Damien Miller13481292014-02-27 10:18:32 +11001193 c->self);
djm@openbsd.orgc04e9792017-05-31 00:43:04 +00001194 return -1;
1195 }
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001196 len = strlen(p);
Ben Lindstrom6fa9d102001-04-11 23:08:17 +00001197 debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001198 len++; /* trailing '\0' */
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001199 strlcpy(username, p, sizeof(username));
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001200 if ((r = sshbuf_consume(input, len)) != 0) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001201 fatal("%s: channel %d: consume: %s", __func__,
1202 c->self, ssh_err(r));
1203 }
Darren Tuckera627d422013-06-02 07:31:17 +10001204 free(c->path);
1205 c->path = NULL;
Damien Miller1781f532009-01-28 16:24:41 +11001206 if (need == 1) { /* SOCKS4: one string */
1207 host = inet_ntoa(s4_req.dest_addr);
Damien Millera1c1b6c2009-01-28 16:29:49 +11001208 c->path = xstrdup(host);
Damien Miller1781f532009-01-28 16:24:41 +11001209 } else { /* SOCKS4A: two strings */
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001210 have = sshbuf_len(input);
1211 p = sshbuf_ptr(input);
djm@openbsd.orgc04e9792017-05-31 00:43:04 +00001212 if (memchr(p, '\0', have) == NULL) {
1213 error("channel %d: decode socks4a: host not nul "
1214 "terminated", c->self);
1215 return -1;
1216 }
Damien Miller1781f532009-01-28 16:24:41 +11001217 len = strlen(p);
1218 debug2("channel %d: decode socks4a: host %s/%d",
1219 c->self, p, len);
1220 len++; /* trailing '\0' */
Damien Millera1c1b6c2009-01-28 16:29:49 +11001221 if (len > NI_MAXHOST) {
Damien Miller1781f532009-01-28 16:24:41 +11001222 error("channel %d: hostname \"%.100s\" too long",
1223 c->self, p);
1224 return -1;
1225 }
Damien Millera1c1b6c2009-01-28 16:29:49 +11001226 c->path = xstrdup(p);
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001227 if ((r = sshbuf_consume(input, len)) != 0) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001228 fatal("%s: channel %d: consume: %s", __func__,
1229 c->self, ssh_err(r));
1230 }
Damien Miller1781f532009-01-28 16:24:41 +11001231 }
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001232 c->host_port = ntohs(s4_req.dest_port);
Damien Miller9f0f5c62001-12-21 14:45:46 +11001233
Damien Millerfbdeece2003-09-02 22:52:31 +10001234 debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
Damien Miller1781f532009-01-28 16:24:41 +11001235 c->self, c->path, c->host_port, s4_req.command);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001236
Ben Lindstromb3921512001-04-11 15:57:50 +00001237 if (s4_req.command != 1) {
Damien Miller1781f532009-01-28 16:24:41 +11001238 debug("channel %d: cannot handle: %s cn %d",
1239 c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
Ben Lindstromb3921512001-04-11 15:57:50 +00001240 return -1;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001241 }
Ben Lindstromb3921512001-04-11 15:57:50 +00001242 s4_rsp.version = 0; /* vn: 0 for reply */
1243 s4_rsp.command = 90; /* cd: req granted */
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001244 s4_rsp.dest_port = 0; /* ignored */
Ben Lindstromb3921512001-04-11 15:57:50 +00001245 s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001246 if ((r = sshbuf_put(output, &s4_rsp, sizeof(s4_rsp))) != 0) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001247 fatal("%s: channel %d: append reply: %s", __func__,
1248 c->self, ssh_err(r));
1249 }
Ben Lindstromb3921512001-04-11 15:57:50 +00001250 return 1;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001251}
1252
Darren Tucker46471c92003-07-03 13:55:19 +10001253/* try to decode a socks5 header */
1254#define SSH_SOCKS5_AUTHDONE 0x1000
1255#define SSH_SOCKS5_NOAUTH 0x00
1256#define SSH_SOCKS5_IPV4 0x01
1257#define SSH_SOCKS5_DOMAIN 0x03
1258#define SSH_SOCKS5_IPV6 0x04
1259#define SSH_SOCKS5_CONNECT 0x01
1260#define SSH_SOCKS5_SUCCESS 0x00
1261
1262static int
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001263channel_decode_socks5(Channel *c, struct sshbuf *input, struct sshbuf *output)
Darren Tucker46471c92003-07-03 13:55:19 +10001264{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001265 /* XXX use get/put_u8 instead of trusting struct padding */
Darren Tucker46471c92003-07-03 13:55:19 +10001266 struct {
1267 u_int8_t version;
1268 u_int8_t command;
1269 u_int8_t reserved;
1270 u_int8_t atyp;
1271 } s5_req, s5_rsp;
1272 u_int16_t dest_port;
Damien Millerce986542013-07-18 16:12:44 +10001273 char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001274 const u_char *p;
Damien Miller0f077072006-07-10 22:21:02 +10001275 u_int have, need, i, found, nmethods, addrlen, af;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001276 int r;
Darren Tucker46471c92003-07-03 13:55:19 +10001277
1278 debug2("channel %d: decode socks5", c->self);
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001279 p = sshbuf_ptr(input);
Darren Tucker46471c92003-07-03 13:55:19 +10001280 if (p[0] != 0x05)
1281 return -1;
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001282 have = sshbuf_len(input);
Darren Tucker46471c92003-07-03 13:55:19 +10001283 if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1284 /* format: ver | nmethods | methods */
Damien Millera8e06ce2003-11-21 23:48:55 +11001285 if (have < 2)
Darren Tucker46471c92003-07-03 13:55:19 +10001286 return 0;
1287 nmethods = p[1];
1288 if (have < nmethods + 2)
1289 return 0;
1290 /* look for method: "NO AUTHENTICATION REQUIRED" */
Damien Miller80163902007-01-05 16:30:16 +11001291 for (found = 0, i = 2; i < nmethods + 2; i++) {
Damien Miller4dec5d72006-08-05 11:38:40 +10001292 if (p[i] == SSH_SOCKS5_NOAUTH) {
Darren Tucker46471c92003-07-03 13:55:19 +10001293 found = 1;
1294 break;
1295 }
1296 }
1297 if (!found) {
1298 debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1299 c->self);
1300 return -1;
1301 }
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001302 if ((r = sshbuf_consume(input, nmethods + 2)) != 0) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001303 fatal("%s: channel %d: consume: %s", __func__,
1304 c->self, ssh_err(r));
1305 }
1306 /* version, method */
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001307 if ((r = sshbuf_put_u8(output, 0x05)) != 0 ||
1308 (r = sshbuf_put_u8(output, SSH_SOCKS5_NOAUTH)) != 0) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001309 fatal("%s: channel %d: append reply: %s", __func__,
1310 c->self, ssh_err(r));
1311 }
Darren Tucker46471c92003-07-03 13:55:19 +10001312 c->flags |= SSH_SOCKS5_AUTHDONE;
1313 debug2("channel %d: socks5 auth done", c->self);
1314 return 0; /* need more */
1315 }
1316 debug2("channel %d: socks5 post auth", c->self);
1317 if (have < sizeof(s5_req)+1)
1318 return 0; /* need more */
Damien Millere3b21a52006-03-26 14:29:06 +11001319 memcpy(&s5_req, p, sizeof(s5_req));
Darren Tucker46471c92003-07-03 13:55:19 +10001320 if (s5_req.version != 0x05 ||
1321 s5_req.command != SSH_SOCKS5_CONNECT ||
1322 s5_req.reserved != 0x00) {
Damien Millerfbdeece2003-09-02 22:52:31 +10001323 debug2("channel %d: only socks5 connect supported", c->self);
Darren Tucker46471c92003-07-03 13:55:19 +10001324 return -1;
1325 }
Darren Tucker47eede72005-03-14 23:08:12 +11001326 switch (s5_req.atyp){
Darren Tucker46471c92003-07-03 13:55:19 +10001327 case SSH_SOCKS5_IPV4:
1328 addrlen = 4;
1329 af = AF_INET;
1330 break;
1331 case SSH_SOCKS5_DOMAIN:
1332 addrlen = p[sizeof(s5_req)];
1333 af = -1;
1334 break;
1335 case SSH_SOCKS5_IPV6:
1336 addrlen = 16;
1337 af = AF_INET6;
1338 break;
1339 default:
Damien Millerfbdeece2003-09-02 22:52:31 +10001340 debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
Darren Tucker46471c92003-07-03 13:55:19 +10001341 return -1;
1342 }
Damien Miller0f077072006-07-10 22:21:02 +10001343 need = sizeof(s5_req) + addrlen + 2;
1344 if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1345 need++;
1346 if (have < need)
Darren Tucker46471c92003-07-03 13:55:19 +10001347 return 0;
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001348 if ((r = sshbuf_consume(input, sizeof(s5_req))) != 0) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001349 fatal("%s: channel %d: consume: %s", __func__,
1350 c->self, ssh_err(r));
1351 }
1352 if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1353 /* host string length */
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001354 if ((r = sshbuf_consume(input, 1)) != 0) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001355 fatal("%s: channel %d: consume: %s", __func__,
1356 c->self, ssh_err(r));
1357 }
1358 }
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001359 if ((r = sshbuf_get(input, &dest_addr, addrlen)) != 0 ||
1360 (r = sshbuf_get(input, &dest_port, 2)) != 0) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001361 debug("channel %d: parse addr/port: %s", c->self, ssh_err(r));
1362 return -1;
1363 }
Darren Tucker46471c92003-07-03 13:55:19 +10001364 dest_addr[addrlen] = '\0';
Darren Tuckera627d422013-06-02 07:31:17 +10001365 free(c->path);
1366 c->path = NULL;
Damien Millera1c1b6c2009-01-28 16:29:49 +11001367 if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
Damien Miller9576ac42009-01-28 16:30:33 +11001368 if (addrlen >= NI_MAXHOST) {
Damien Millera1c1b6c2009-01-28 16:29:49 +11001369 error("channel %d: dynamic request: socks5 hostname "
1370 "\"%.100s\" too long", c->self, dest_addr);
1371 return -1;
1372 }
1373 c->path = xstrdup(dest_addr);
1374 } else {
1375 if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1376 return -1;
1377 c->path = xstrdup(ntop);
1378 }
Darren Tucker46471c92003-07-03 13:55:19 +10001379 c->host_port = ntohs(dest_port);
Damien Miller787b2ec2003-11-21 23:56:47 +11001380
Damien Millerfbdeece2003-09-02 22:52:31 +10001381 debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
Darren Tucker46471c92003-07-03 13:55:19 +10001382 c->self, c->path, c->host_port, s5_req.command);
1383
1384 s5_rsp.version = 0x05;
1385 s5_rsp.command = SSH_SOCKS5_SUCCESS;
1386 s5_rsp.reserved = 0; /* ignored */
1387 s5_rsp.atyp = SSH_SOCKS5_IPV4;
Darren Tucker46471c92003-07-03 13:55:19 +10001388 dest_port = 0; /* ignored */
1389
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001390 if ((r = sshbuf_put(output, &s5_rsp, sizeof(s5_rsp))) != 0 ||
1391 (r = sshbuf_put_u32(output, ntohl(INADDR_ANY))) != 0 ||
1392 (r = sshbuf_put(output, &dest_port, sizeof(dest_port))) != 0)
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001393 fatal("%s: channel %d: append reply: %s", __func__,
1394 c->self, ssh_err(r));
Darren Tucker46471c92003-07-03 13:55:19 +10001395 return 1;
1396}
1397
Darren Tucker7ad8dd22010-01-12 19:40:27 +11001398Channel *
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001399channel_connect_stdio_fwd(struct ssh *ssh,
1400 const char *host_to_connect, u_short port_to_connect, int in, int out)
Darren Tucker7ad8dd22010-01-12 19:40:27 +11001401{
1402 Channel *c;
Darren Tucker7ad8dd22010-01-12 19:40:27 +11001403
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001404 debug("%s %s:%d", __func__, host_to_connect, port_to_connect);
Darren Tucker7ad8dd22010-01-12 19:40:27 +11001405
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001406 c = channel_new(ssh, "stdio-forward", SSH_CHANNEL_OPENING, in, out,
Darren Tucker7ad8dd22010-01-12 19:40:27 +11001407 -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1408 0, "stdio-forward", /*nonblock*/0);
1409
1410 c->path = xstrdup(host_to_connect);
1411 c->host_port = port_to_connect;
1412 c->listening_port = 0;
1413 c->force_drain = 1;
1414
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001415 channel_register_fds(ssh, c, in, out, -1, 0, 1, 0);
1416 port_open_helper(ssh, c, "direct-tcpip");
Darren Tucker7ad8dd22010-01-12 19:40:27 +11001417
1418 return c;
1419}
1420
Ben Lindstromb3921512001-04-11 15:57:50 +00001421/* dynamic port forwarding */
Ben Lindstrombba81212001-06-25 05:01:22 +00001422static void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001423channel_pre_dynamic(struct ssh *ssh, Channel *c,
1424 fd_set *readset, fd_set *writeset)
Ben Lindstromb3921512001-04-11 15:57:50 +00001425{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001426 const u_char *p;
Damien Millereccb9de2005-06-17 12:59:34 +10001427 u_int have;
1428 int ret;
Ben Lindstromb3921512001-04-11 15:57:50 +00001429
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001430 have = sshbuf_len(c->input);
Ben Lindstromb3921512001-04-11 15:57:50 +00001431 debug2("channel %d: pre_dynamic: have %d", c->self, have);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001432 /* sshbuf_dump(c->input, stderr); */
Ben Lindstromb3921512001-04-11 15:57:50 +00001433 /* check if the fixed size part of the packet is in buffer. */
Darren Tucker46471c92003-07-03 13:55:19 +10001434 if (have < 3) {
Ben Lindstromb3921512001-04-11 15:57:50 +00001435 /* need more */
1436 FD_SET(c->sock, readset);
1437 return;
1438 }
1439 /* try to guess the protocol */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001440 p = sshbuf_ptr(c->input);
1441 /* XXX sshbuf_peek_u8? */
Ben Lindstromb3921512001-04-11 15:57:50 +00001442 switch (p[0]) {
Ben Lindstrom6fa9d102001-04-11 23:08:17 +00001443 case 0x04:
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001444 ret = channel_decode_socks4(c, c->input, c->output);
Ben Lindstrom6fa9d102001-04-11 23:08:17 +00001445 break;
Darren Tucker46471c92003-07-03 13:55:19 +10001446 case 0x05:
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001447 ret = channel_decode_socks5(c, c->input, c->output);
Darren Tucker46471c92003-07-03 13:55:19 +10001448 break;
Ben Lindstromb3921512001-04-11 15:57:50 +00001449 default:
1450 ret = -1;
1451 break;
1452 }
1453 if (ret < 0) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001454 chan_mark_dead(ssh, c);
Ben Lindstromb3921512001-04-11 15:57:50 +00001455 } else if (ret == 0) {
1456 debug2("channel %d: pre_dynamic: need more", c->self);
1457 /* need more */
1458 FD_SET(c->sock, readset);
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001459 if (sshbuf_len(c->output))
1460 FD_SET(c->sock, writeset);
Ben Lindstromb3921512001-04-11 15:57:50 +00001461 } else {
1462 /* switch to the next state */
1463 c->type = SSH_CHANNEL_OPENING;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001464 port_open_helper(ssh, c, "direct-tcpip");
Ben Lindstromb3921512001-04-11 15:57:50 +00001465 }
1466}
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001467
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001468/* simulate read-error */
1469static void
1470rdynamic_close(struct ssh *ssh, Channel *c)
1471{
1472 c->type = SSH_CHANNEL_OPEN;
1473 chan_read_failed(ssh, c);
1474 sshbuf_reset(c->input);
1475 chan_ibuf_empty(ssh, c);
1476 sshbuf_reset(c->output);
1477 chan_write_failed(ssh, c);
1478}
1479
1480/* reverse dynamic port forwarding */
1481static void
1482channel_before_prepare_select_rdynamic(struct ssh *ssh, Channel *c)
1483{
1484 const u_char *p;
1485 u_int have, len;
1486 int r, ret;
1487
1488 have = sshbuf_len(c->output);
1489 debug2("channel %d: pre_rdynamic: have %d", c->self, have);
1490 /* sshbuf_dump(c->output, stderr); */
1491 /* EOF received */
1492 if (c->flags & CHAN_EOF_RCVD) {
1493 if ((r = sshbuf_consume(c->output, have)) != 0) {
1494 fatal("%s: channel %d: consume: %s",
1495 __func__, c->self, ssh_err(r));
1496 }
1497 rdynamic_close(ssh, c);
1498 return;
1499 }
1500 /* check if the fixed size part of the packet is in buffer. */
1501 if (have < 3)
1502 return;
1503 /* try to guess the protocol */
1504 p = sshbuf_ptr(c->output);
1505 switch (p[0]) {
1506 case 0x04:
1507 /* switch input/output for reverse forwarding */
1508 ret = channel_decode_socks4(c, c->output, c->input);
1509 break;
1510 case 0x05:
1511 ret = channel_decode_socks5(c, c->output, c->input);
1512 break;
1513 default:
1514 ret = -1;
1515 break;
1516 }
1517 if (ret < 0) {
1518 rdynamic_close(ssh, c);
1519 } else if (ret == 0) {
1520 debug2("channel %d: pre_rdynamic: need more", c->self);
1521 /* send socks request to peer */
1522 len = sshbuf_len(c->input);
1523 if (len > 0 && len < c->remote_window) {
1524 if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
1525 (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1526 (r = sshpkt_put_stringb(ssh, c->input)) != 0 ||
1527 (r = sshpkt_send(ssh)) != 0) {
1528 fatal("%s: channel %i: rdynamic: %s", __func__,
1529 c->self, ssh_err(r));
1530 }
1531 if ((r = sshbuf_consume(c->input, len)) != 0) {
1532 fatal("%s: channel %d: consume: %s",
1533 __func__, c->self, ssh_err(r));
1534 }
1535 c->remote_window -= len;
1536 }
1537 } else if (rdynamic_connect_finish(ssh, c) < 0) {
1538 /* the connect failed */
1539 rdynamic_close(ssh, c);
1540 }
1541}
1542
Damien Millerb38eff82000-04-01 11:09:21 +10001543/* This is our fake X11 server socket. */
Ben Lindstrombba81212001-06-25 05:01:22 +00001544static void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001545channel_post_x11_listener(struct ssh *ssh, Channel *c,
1546 fd_set *readset, fd_set *writeset)
Damien Millerb38eff82000-04-01 11:09:21 +10001547{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001548 Channel *nc;
Damien Miller163886f2008-07-14 11:28:58 +10001549 struct sockaddr_storage addr;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001550 int r, newsock, oerrno, remote_port;
Damien Millerb38eff82000-04-01 11:09:21 +10001551 socklen_t addrlen;
Damien Millerd83ff352001-01-30 09:19:34 +11001552 char buf[16384], *remote_ipaddr;
Damien Millerb38eff82000-04-01 11:09:21 +10001553
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001554 if (!FD_ISSET(c->sock, readset))
1555 return;
Damien Millerbd483e72000-04-30 10:00:53 +10001556
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001557 debug("X11 connection requested.");
1558 addrlen = sizeof(addr);
1559 newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1560 if (c->single_connection) {
1561 oerrno = errno;
1562 debug2("single_connection: closing X11 listener.");
1563 channel_close_fd(ssh, &c->sock);
1564 chan_mark_dead(ssh, c);
1565 errno = oerrno;
Damien Millerb38eff82000-04-01 11:09:21 +10001566 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001567 if (newsock < 0) {
1568 if (errno != EINTR && errno != EWOULDBLOCK &&
1569 errno != ECONNABORTED)
1570 error("accept: %.100s", strerror(errno));
1571 if (errno == EMFILE || errno == ENFILE)
1572 c->notbefore = monotime() + 1;
1573 return;
1574 }
1575 set_nodelay(newsock);
1576 remote_ipaddr = get_peer_ipaddr(newsock);
1577 remote_port = get_peer_port(newsock);
1578 snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1579 remote_ipaddr, remote_port);
1580
1581 nc = channel_new(ssh, "accepted x11 socket",
1582 SSH_CHANNEL_OPENING, newsock, newsock, -1,
1583 c->local_window_max, c->local_maxpacket, 0, buf, 1);
1584 open_preamble(ssh, __func__, nc, "x11");
1585 if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0) {
1586 fatal("%s: channel %i: reply %s", __func__,
1587 c->self, ssh_err(r));
1588 }
1589 if ((datafellows & SSH_BUG_X11FWD) != 0)
1590 debug2("channel %d: ssh2 x11 bug compat mode", nc->self);
1591 else if ((r = sshpkt_put_u32(ssh, remote_port)) != 0) {
1592 fatal("%s: channel %i: reply %s", __func__,
1593 c->self, ssh_err(r));
1594 }
1595 if ((r = sshpkt_send(ssh)) != 0)
1596 fatal("%s: channel %i: send %s", __func__, c->self, ssh_err(r));
1597 free(remote_ipaddr);
Damien Millerb38eff82000-04-01 11:09:21 +10001598}
1599
Ben Lindstrombba81212001-06-25 05:01:22 +00001600static void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001601port_open_helper(struct ssh *ssh, Channel *c, char *rtype)
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001602{
Damien Miller4def1842013-12-29 17:45:26 +11001603 char *local_ipaddr = get_local_ipaddr(c->sock);
djm@openbsd.org95767262016-03-07 19:02:43 +00001604 int local_port = c->sock == -1 ? 65536 : get_local_port(c->sock);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001605 char *remote_ipaddr = get_peer_ipaddr(c->sock);
Damien Miller677257f2005-06-17 12:55:03 +10001606 int remote_port = get_peer_port(c->sock);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001607 int r;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001608
Damien Millerd6369432010-02-02 17:02:07 +11001609 if (remote_port == -1) {
1610 /* Fake addr/port to appease peers that validate it (Tectia) */
Darren Tuckera627d422013-06-02 07:31:17 +10001611 free(remote_ipaddr);
Damien Millerd6369432010-02-02 17:02:07 +11001612 remote_ipaddr = xstrdup("127.0.0.1");
1613 remote_port = 65535;
1614 }
1615
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001616 free(c->remote_name);
1617 xasprintf(&c->remote_name,
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001618 "%s: listening port %d for %.100s port %d, "
Damien Miller4def1842013-12-29 17:45:26 +11001619 "connect from %.200s port %d to %.100s port %d",
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001620 rtype, c->listening_port, c->path, c->host_port,
Damien Miller4def1842013-12-29 17:45:26 +11001621 remote_ipaddr, remote_port, local_ipaddr, local_port);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001622
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001623 open_preamble(ssh, __func__, c, rtype);
djm@openbsd.org97f4d302017-04-30 23:13:25 +00001624 if (strcmp(rtype, "direct-tcpip") == 0) {
1625 /* target host, port */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001626 if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1627 (r = sshpkt_put_u32(ssh, c->host_port)) != 0) {
1628 fatal("%s: channel %i: reply %s", __func__,
1629 c->self, ssh_err(r));
1630 }
djm@openbsd.org97f4d302017-04-30 23:13:25 +00001631 } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1632 /* target path */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001633 if ((r = sshpkt_put_cstring(ssh, c->path)) != 0) {
1634 fatal("%s: channel %i: reply %s", __func__,
1635 c->self, ssh_err(r));
1636 }
djm@openbsd.org97f4d302017-04-30 23:13:25 +00001637 } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1638 /* listen path */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001639 if ((r = sshpkt_put_cstring(ssh, c->path)) != 0) {
1640 fatal("%s: channel %i: reply %s", __func__,
1641 c->self, ssh_err(r));
1642 }
djm@openbsd.org97f4d302017-04-30 23:13:25 +00001643 } else {
1644 /* listen address, port */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001645 if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1646 (r = sshpkt_put_u32(ssh, local_port)) != 0) {
1647 fatal("%s: channel %i: reply %s", __func__,
1648 c->self, ssh_err(r));
1649 }
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001650 }
djm@openbsd.org97f4d302017-04-30 23:13:25 +00001651 if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1652 /* reserved for future owner/mode info */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001653 if ((r = sshpkt_put_cstring(ssh, "")) != 0) {
1654 fatal("%s: channel %i: reply %s", __func__,
1655 c->self, ssh_err(r));
1656 }
djm@openbsd.org97f4d302017-04-30 23:13:25 +00001657 } else {
1658 /* originator host and port */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001659 if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1660 (r = sshpkt_put_u32(ssh, (u_int)remote_port)) != 0) {
1661 fatal("%s: channel %i: reply %s", __func__,
1662 c->self, ssh_err(r));
1663 }
djm@openbsd.org97f4d302017-04-30 23:13:25 +00001664 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001665 if ((r = sshpkt_send(ssh)) != 0)
1666 fatal("%s: channel %i: send %s", __func__, c->self, ssh_err(r));
Darren Tuckera627d422013-06-02 07:31:17 +10001667 free(remote_ipaddr);
Damien Miller4def1842013-12-29 17:45:26 +11001668 free(local_ipaddr);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001669}
1670
Damien Miller5e7fd072005-11-05 14:53:39 +11001671static void
1672channel_set_reuseaddr(int fd)
1673{
1674 int on = 1;
1675
1676 /*
1677 * Set socket options.
1678 * Allow local port reuse in TIME_WAIT.
1679 */
1680 if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
1681 error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
1682}
1683
djm@openbsd.org1bf477d2015-07-01 02:26:31 +00001684void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001685channel_set_x11_refuse_time(struct ssh *ssh, u_int refuse_time)
djm@openbsd.org1bf477d2015-07-01 02:26:31 +00001686{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001687 ssh->chanctxt->x11_refuse_time = refuse_time;
djm@openbsd.org1bf477d2015-07-01 02:26:31 +00001688}
1689
Damien Millerb38eff82000-04-01 11:09:21 +10001690/*
1691 * This socket is listening for connections to a forwarded TCP/IP port.
1692 */
Ben Lindstrombba81212001-06-25 05:01:22 +00001693static void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001694channel_post_port_listener(struct ssh *ssh, Channel *c,
1695 fd_set *readset, fd_set *writeset)
Damien Millerb38eff82000-04-01 11:09:21 +10001696{
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001697 Channel *nc;
Damien Miller163886f2008-07-14 11:28:58 +10001698 struct sockaddr_storage addr;
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001699 int newsock, nextstate;
Damien Millerb38eff82000-04-01 11:09:21 +10001700 socklen_t addrlen;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001701 char *rtype;
Damien Miller0bc1bd82000-11-13 22:57:25 +11001702
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001703 if (!FD_ISSET(c->sock, readset))
1704 return;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001705
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001706 debug("Connection to port %d forwarding to %.100s port %d requested.",
1707 c->listening_port, c->path, c->host_port);
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +00001708
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001709 if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1710 nextstate = SSH_CHANNEL_OPENING;
1711 rtype = "forwarded-tcpip";
1712 } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1713 nextstate = SSH_CHANNEL_OPENING;
1714 rtype = "forwarded-streamlocal@openssh.com";
1715 } else if (c->host_port == PORT_STREAMLOCAL) {
1716 nextstate = SSH_CHANNEL_OPENING;
1717 rtype = "direct-streamlocal@openssh.com";
1718 } else if (c->host_port == 0) {
1719 nextstate = SSH_CHANNEL_DYNAMIC;
1720 rtype = "dynamic-tcpip";
1721 } else {
1722 nextstate = SSH_CHANNEL_OPENING;
1723 rtype = "direct-tcpip";
Damien Millerb38eff82000-04-01 11:09:21 +10001724 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001725
1726 addrlen = sizeof(addr);
1727 newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1728 if (newsock < 0) {
1729 if (errno != EINTR && errno != EWOULDBLOCK &&
1730 errno != ECONNABORTED)
1731 error("accept: %.100s", strerror(errno));
1732 if (errno == EMFILE || errno == ENFILE)
1733 c->notbefore = monotime() + 1;
1734 return;
1735 }
1736 if (c->host_port != PORT_STREAMLOCAL)
1737 set_nodelay(newsock);
1738 nc = channel_new(ssh, rtype, nextstate, newsock, newsock, -1,
1739 c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1740 nc->listening_port = c->listening_port;
1741 nc->host_port = c->host_port;
1742 if (c->path != NULL)
1743 nc->path = xstrdup(c->path);
1744
1745 if (nextstate != SSH_CHANNEL_DYNAMIC)
1746 port_open_helper(ssh, nc, rtype);
Damien Millerb38eff82000-04-01 11:09:21 +10001747}
1748
1749/*
1750 * This is the authentication agent socket listening for connections from
1751 * clients.
1752 */
Ben Lindstrombba81212001-06-25 05:01:22 +00001753static void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001754channel_post_auth_listener(struct ssh *ssh, Channel *c,
1755 fd_set *readset, fd_set *writeset)
Damien Millerb38eff82000-04-01 11:09:21 +10001756{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00001757 Channel *nc;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001758 int r, newsock;
Damien Miller163886f2008-07-14 11:28:58 +10001759 struct sockaddr_storage addr;
Damien Millerb38eff82000-04-01 11:09:21 +10001760 socklen_t addrlen;
1761
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001762 if (!FD_ISSET(c->sock, readset))
1763 return;
1764
1765 addrlen = sizeof(addr);
1766 newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1767 if (newsock < 0) {
1768 error("accept from auth socket: %.100s", strerror(errno));
1769 if (errno == EMFILE || errno == ENFILE)
1770 c->notbefore = monotime() + 1;
1771 return;
Damien Millerb38eff82000-04-01 11:09:21 +10001772 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001773 nc = channel_new(ssh, "accepted auth socket",
1774 SSH_CHANNEL_OPENING, newsock, newsock, -1,
1775 c->local_window_max, c->local_maxpacket,
1776 0, "accepted auth socket", 1);
1777 open_preamble(ssh, __func__, nc, "auth-agent@openssh.com");
1778 if ((r = sshpkt_send(ssh)) != 0)
1779 fatal("%s: channel %i: %s", __func__, c->self, ssh_err(r));
Damien Millerb38eff82000-04-01 11:09:21 +10001780}
1781
Ben Lindstrombba81212001-06-25 05:01:22 +00001782static void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001783channel_post_connecting(struct ssh *ssh, Channel *c,
1784 fd_set *readset, fd_set *writeset)
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001785{
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001786 int err = 0, sock, isopen, r;
Ben Lindstrom11180952001-07-04 05:13:35 +00001787 socklen_t sz = sizeof(err);
Ben Lindstrom69128662001-05-08 20:07:39 +00001788
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001789 if (!FD_ISSET(c->sock, writeset))
1790 return;
djm@openbsd.org9f532292017-09-12 06:35:31 +00001791 if (!c->have_remote_id)
1792 fatal(":%s: channel %d: no remote id", __func__, c->self);
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001793 /* for rdynamic the OPEN_CONFIRMATION has been sent already */
1794 isopen = (c->type == SSH_CHANNEL_RDYNAMIC_FINISH);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001795 if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
1796 err = errno;
1797 error("getsockopt SO_ERROR failed");
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001798 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001799 if (err == 0) {
1800 debug("channel %d: connected to %s port %d",
1801 c->self, c->connect_ctx.host, c->connect_ctx.port);
1802 channel_connect_ctx_free(&c->connect_ctx);
1803 c->type = SSH_CHANNEL_OPEN;
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001804 if (isopen) {
1805 /* no message necessary */
1806 } else {
1807 if ((r = sshpkt_start(ssh,
1808 SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
1809 (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1810 (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
1811 (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1812 (r = sshpkt_put_u32(ssh, c->local_maxpacket))
1813 != 0)
1814 fatal("%s: channel %i: confirm: %s", __func__,
1815 c->self, ssh_err(r));
1816 if ((r = sshpkt_send(ssh)) != 0)
1817 fatal("%s: channel %i: %s", __func__, c->self,
1818 ssh_err(r));
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001819 }
1820 } else {
1821 debug("channel %d: connection failed: %s",
1822 c->self, strerror(err));
1823 /* Try next address, if any */
1824 if ((sock = connect_next(&c->connect_ctx)) > 0) {
1825 close(c->sock);
1826 c->sock = c->rfd = c->wfd = sock;
1827 channel_find_maxfd(ssh->chanctxt);
1828 return;
1829 }
1830 /* Exhausted all addresses */
1831 error("connect_to %.100s port %d: failed.",
1832 c->connect_ctx.host, c->connect_ctx.port);
1833 channel_connect_ctx_free(&c->connect_ctx);
markus@openbsd.org609d7a62017-09-21 19:16:53 +00001834 if (isopen) {
1835 rdynamic_close(ssh, c);
1836 } else {
1837 if ((r = sshpkt_start(ssh,
1838 SSH2_MSG_CHANNEL_OPEN_FAILURE)) != 0 ||
1839 (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1840 (r = sshpkt_put_u32(ssh, SSH2_OPEN_CONNECT_FAILED))
1841 != 0)
1842 fatal("%s: channel %i: failure: %s", __func__,
1843 c->self, ssh_err(r));
1844 if ((datafellows & SSH_BUG_OPENFAILURE) == 0 &&
1845 ((r = sshpkt_put_cstring(ssh, strerror(err))) != 0 ||
1846 (r = sshpkt_put_cstring(ssh, "")) != 0))
1847 fatal("%s: channel %i: failure: %s", __func__,
1848 c->self, ssh_err(r));
1849 if ((r = sshpkt_send(ssh)) != 0)
1850 fatal("%s: channel %i: %s", __func__, c->self,
1851 ssh_err(r));
1852 chan_mark_dead(ssh, c);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001853 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001854 }
Ben Lindstrom7ad97102000-12-06 01:42:49 +00001855}
1856
Ben Lindstrombba81212001-06-25 05:01:22 +00001857static int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001858channel_handle_rfd(struct ssh *ssh, Channel *c,
1859 fd_set *readset, fd_set *writeset)
Damien Millerb38eff82000-04-01 11:09:21 +10001860{
Darren Tucker11327cc2005-03-14 23:22:25 +11001861 char buf[CHAN_RBUF];
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001862 ssize_t len;
1863 int r, force;
Damien Millerb38eff82000-04-01 11:09:21 +10001864
Damien Miller835284b2007-06-11 13:03:16 +10001865 force = c->isatty && c->detach_close && c->istate != CHAN_INPUT_CLOSED;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001866
1867 if (c->rfd == -1 || (!force && !FD_ISSET(c->rfd, readset)))
1868 return 1;
1869
1870 errno = 0;
1871 len = read(c->rfd, buf, sizeof(buf));
1872 if (len < 0 && (errno == EINTR ||
1873 ((errno == EAGAIN || errno == EWOULDBLOCK) && !force)))
1874 return 1;
Darren Tucker9afe1152006-06-23 21:24:12 +10001875#ifndef PTY_ZEROREAD
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001876 if (len <= 0) {
Darren Tucker9afe1152006-06-23 21:24:12 +10001877#else
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001878 if ((!c->isatty && len <= 0) ||
1879 (c->isatty && (len < 0 || (len == 0 && errno != 0)))) {
Darren Tucker9afe1152006-06-23 21:24:12 +10001880#endif
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001881 debug2("channel %d: read<=0 rfd %d len %zd",
1882 c->self, c->rfd, len);
1883 if (c->type != SSH_CHANNEL_OPEN) {
1884 debug2("channel %d: not open", c->self);
1885 chan_mark_dead(ssh, c);
Damien Millerb38eff82000-04-01 11:09:21 +10001886 return -1;
Damien Millerad833b32000-08-23 10:46:23 +10001887 } else {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001888 chan_read_failed(ssh, c);
Damien Millerad833b32000-08-23 10:46:23 +10001889 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001890 return -1;
1891 }
1892 if (c->input_filter != NULL) {
1893 if (c->input_filter(ssh, c, buf, len) == -1) {
1894 debug2("channel %d: filter stops", c->self);
1895 chan_read_failed(ssh, c);
1896 }
1897 } else if (c->datagram) {
1898 if ((r = sshbuf_put_string(c->input, buf, len)) != 0)
1899 fatal("%s: channel %d: put datagram: %s", __func__,
1900 c->self, ssh_err(r));
1901 } else if ((r = sshbuf_put(c->input, buf, len)) != 0) {
1902 fatal("%s: channel %d: put data: %s", __func__,
1903 c->self, ssh_err(r));
Damien Millerb38eff82000-04-01 11:09:21 +10001904 }
1905 return 1;
1906}
Damien Miller4f7becb2006-03-26 14:10:14 +11001907
Ben Lindstrombba81212001-06-25 05:01:22 +00001908static int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001909channel_handle_wfd(struct ssh *ssh, Channel *c,
1910 fd_set *readset, fd_set *writeset)
Damien Millerb38eff82000-04-01 11:09:21 +10001911{
Ben Lindstrome229b252001-03-05 06:28:06 +00001912 struct termios tio;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001913 u_char *data = NULL, *buf; /* XXX const; need filter API change */
1914 size_t dlen, olen = 0;
1915 int r, len;
1916
1917 if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
1918 sshbuf_len(c->output) == 0)
1919 return 1;
Damien Millerb38eff82000-04-01 11:09:21 +10001920
1921 /* Send buffered output data to the socket. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001922 olen = sshbuf_len(c->output);
1923 if (c->output_filter != NULL) {
1924 if ((buf = c->output_filter(ssh, c, &data, &dlen)) == NULL) {
1925 debug2("channel %d: filter stops", c->self);
1926 if (c->type != SSH_CHANNEL_OPEN)
1927 chan_mark_dead(ssh, c);
1928 else
1929 chan_write_failed(ssh, c);
Damien Millerb38eff82000-04-01 11:09:21 +10001930 return -1;
1931 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001932 } else if (c->datagram) {
1933 if ((r = sshbuf_get_string(c->output, &data, &dlen)) != 0)
1934 fatal("%s: channel %d: get datagram: %s", __func__,
1935 c->self, ssh_err(r));
djm@openbsd.org9145a732017-09-12 07:32:04 +00001936 buf = data;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001937 } else {
1938 buf = data = sshbuf_mutable_ptr(c->output);
1939 dlen = sshbuf_len(c->output);
1940 }
1941
1942 if (c->datagram) {
1943 /* ignore truncated writes, datagrams might get lost */
djm@openbsd.orgc704f642017-09-24 09:50:01 +00001944 len = write(c->wfd, buf, dlen);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001945 free(data);
1946 if (len < 0 && (errno == EINTR || errno == EAGAIN ||
1947 errno == EWOULDBLOCK))
1948 return 1;
1949 if (len <= 0)
1950 goto write_fail;
1951 goto out;
1952 }
1953
1954#ifdef _AIX
1955 /* XXX: Later AIX versions can't push as much data to tty */
1956 if (c->wfd_isatty)
1957 dlen = MIN(dlen, 8*1024);
Darren Tucker3980b632009-08-28 11:02:37 +10001958#endif
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001959
1960 len = write(c->wfd, buf, dlen);
1961 if (len < 0 &&
1962 (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK))
1963 return 1;
1964 if (len <= 0) {
1965 write_fail:
1966 if (c->type != SSH_CHANNEL_OPEN) {
1967 debug2("channel %d: not open", c->self);
1968 chan_mark_dead(ssh, c);
1969 return -1;
1970 } else {
1971 chan_write_failed(ssh, c);
1972 }
1973 return -1;
1974 }
1975#ifndef BROKEN_TCGETATTR_ICANON
1976 if (c->isatty && dlen >= 1 && buf[0] != '\r') {
1977 if (tcgetattr(c->wfd, &tio) == 0 &&
1978 !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1979 /*
1980 * Simulate echo to reduce the impact of
1981 * traffic analysis. We need to match the
1982 * size of a SSH2_MSG_CHANNEL_DATA message
1983 * (4 byte channel id + buf)
1984 */
1985 if ((r = sshpkt_msg_ignore(ssh, 4+len)) != 0 ||
1986 (r = sshpkt_send(ssh)) != 0)
1987 fatal("%s: channel %d: ignore: %s",
1988 __func__, c->self, ssh_err(r));
1989 }
1990 }
1991#endif /* BROKEN_TCGETATTR_ICANON */
1992 if ((r = sshbuf_consume(c->output, len)) != 0) {
1993 fatal("%s: channel %d: consume: %s",
1994 __func__, c->self, ssh_err(r));
Damien Miller33b13562000-04-04 14:38:59 +10001995 }
Damien Miller7d457182010-08-05 23:09:48 +10001996 out:
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00001997 c->local_consumed += olen - sshbuf_len(c->output);
1998
Damien Miller33b13562000-04-04 14:38:59 +10001999 return 1;
2000}
Damien Miller4f7becb2006-03-26 14:10:14 +11002001
Ben Lindstrombba81212001-06-25 05:01:22 +00002002static int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002003channel_handle_efd_write(struct ssh *ssh, Channel *c,
2004 fd_set *readset, fd_set *writeset)
2005{
2006 int r;
2007 ssize_t len;
2008
2009 if (!FD_ISSET(c->efd, writeset) || sshbuf_len(c->extended) == 0)
2010 return 1;
2011
2012 len = write(c->efd, sshbuf_ptr(c->extended),
2013 sshbuf_len(c->extended));
2014 debug2("channel %d: written %zd to efd %d", c->self, len, c->efd);
2015 if (len < 0 && (errno == EINTR || errno == EAGAIN ||
2016 errno == EWOULDBLOCK))
2017 return 1;
2018 if (len <= 0) {
2019 debug2("channel %d: closing write-efd %d", c->self, c->efd);
2020 channel_close_fd(ssh, &c->efd);
2021 } else {
2022 if ((r = sshbuf_consume(c->extended, len)) != 0) {
2023 fatal("%s: channel %d: consume: %s",
2024 __func__, c->self, ssh_err(r));
2025 }
2026 c->local_consumed += len;
2027 }
2028 return 1;
2029}
2030
2031static int
2032channel_handle_efd_read(struct ssh *ssh, Channel *c,
2033 fd_set *readset, fd_set *writeset)
Damien Miller33b13562000-04-04 14:38:59 +10002034{
Darren Tucker11327cc2005-03-14 23:22:25 +11002035 char buf[CHAN_RBUF];
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002036 int r;
2037 ssize_t len;
Damien Miller33b13562000-04-04 14:38:59 +10002038
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002039 if (!c->detach_close && !FD_ISSET(c->efd, readset))
2040 return 1;
2041
2042 len = read(c->efd, buf, sizeof(buf));
2043 debug2("channel %d: read %zd from efd %d", c->self, len, c->efd);
2044 if (len < 0 && (errno == EINTR || ((errno == EAGAIN ||
2045 errno == EWOULDBLOCK) && !c->detach_close)))
2046 return 1;
2047 if (len <= 0) {
2048 debug2("channel %d: closing read-efd %d",
2049 c->self, c->efd);
2050 channel_close_fd(ssh, &c->efd);
2051 } else {
2052 if (c->extended_usage == CHAN_EXTENDED_IGNORE) {
2053 debug3("channel %d: discard efd",
2054 c->self);
2055 } else if ((r = sshbuf_put(c->extended, buf, len)) != 0) {
2056 fatal("%s: channel %d: append: %s",
2057 __func__, c->self, ssh_err(r));
Damien Miller33b13562000-04-04 14:38:59 +10002058 }
2059 }
2060 return 1;
2061}
Damien Miller4f7becb2006-03-26 14:10:14 +11002062
Damien Miller0e220db2004-06-15 10:34:08 +10002063static int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002064channel_handle_efd(struct ssh *ssh, Channel *c,
2065 fd_set *readset, fd_set *writeset)
Damien Miller33b13562000-04-04 14:38:59 +10002066{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002067 if (c->efd == -1)
2068 return 1;
2069
2070 /** XXX handle drain efd, too */
2071
2072 if (c->extended_usage == CHAN_EXTENDED_WRITE)
2073 return channel_handle_efd_write(ssh, c, readset, writeset);
2074 else if (c->extended_usage == CHAN_EXTENDED_READ ||
2075 c->extended_usage == CHAN_EXTENDED_IGNORE)
2076 return channel_handle_efd_read(ssh, c, readset, writeset);
2077
2078 return 1;
2079}
2080
2081static int
2082channel_check_window(struct ssh *ssh, Channel *c)
2083{
2084 int r;
2085
Ben Lindstromb3921512001-04-11 15:57:50 +00002086 if (c->type == SSH_CHANNEL_OPEN &&
2087 !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
Darren Tuckerae09cb82007-06-25 19:04:46 +10002088 ((c->local_window_max - c->local_window >
Damien Miller3191a8e2007-06-11 18:33:15 +10002089 c->local_maxpacket*3) ||
2090 c->local_window < c->local_window_max/2) &&
Damien Miller33b13562000-04-04 14:38:59 +10002091 c->local_consumed > 0) {
djm@openbsd.org9f532292017-09-12 06:35:31 +00002092 if (!c->have_remote_id)
2093 fatal(":%s: channel %d: no remote id",
2094 __func__, c->self);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002095 if ((r = sshpkt_start(ssh,
2096 SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
2097 (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2098 (r = sshpkt_put_u32(ssh, c->local_consumed)) != 0 ||
2099 (r = sshpkt_send(ssh)) != 0) {
2100 fatal("%s: channel %i: %s", __func__,
2101 c->self, ssh_err(r));
2102 }
Damien Millerd3444942000-09-30 14:20:03 +11002103 debug2("channel %d: window %d sent adjust %d",
Damien Miller33b13562000-04-04 14:38:59 +10002104 c->self, c->local_window,
2105 c->local_consumed);
2106 c->local_window += c->local_consumed;
2107 c->local_consumed = 0;
Damien Millerb38eff82000-04-01 11:09:21 +10002108 }
2109 return 1;
2110}
2111
Ben Lindstrombba81212001-06-25 05:01:22 +00002112static void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002113channel_post_open(struct ssh *ssh, Channel *c,
2114 fd_set *readset, fd_set *writeset)
Damien Millerb38eff82000-04-01 11:09:21 +10002115{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002116 channel_handle_rfd(ssh, c, readset, writeset);
2117 channel_handle_wfd(ssh, c, readset, writeset);
2118 channel_handle_efd(ssh, c, readset, writeset);
2119 channel_check_window(ssh, c);
Damien Miller33b13562000-04-04 14:38:59 +10002120}
2121
Damien Millere1537f92010-01-26 13:26:22 +11002122static u_int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002123read_mux(struct ssh *ssh, Channel *c, u_int need)
Damien Millere1537f92010-01-26 13:26:22 +11002124{
2125 char buf[CHAN_RBUF];
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002126 ssize_t len;
Damien Millere1537f92010-01-26 13:26:22 +11002127 u_int rlen;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002128 int r;
Damien Millere1537f92010-01-26 13:26:22 +11002129
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002130 if (sshbuf_len(c->input) < need) {
2131 rlen = need - sshbuf_len(c->input);
deraadt@openbsd.org9136ec12016-09-12 01:22:38 +00002132 len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF));
naddy@openbsd.org603ba412016-02-05 13:28:19 +00002133 if (len < 0 && (errno == EINTR || errno == EAGAIN))
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002134 return sshbuf_len(c->input);
Damien Millere1537f92010-01-26 13:26:22 +11002135 if (len <= 0) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002136 debug2("channel %d: ctl read<=0 rfd %d len %zd",
naddy@openbsd.org603ba412016-02-05 13:28:19 +00002137 c->self, c->rfd, len);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002138 chan_read_failed(ssh, c);
naddy@openbsd.org603ba412016-02-05 13:28:19 +00002139 return 0;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002140 } else if ((r = sshbuf_put(c->input, buf, len)) != 0) {
2141 fatal("%s: channel %d: append: %s",
2142 __func__, c->self, ssh_err(r));
2143 }
Damien Millere1537f92010-01-26 13:26:22 +11002144 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002145 return sshbuf_len(c->input);
Damien Millere1537f92010-01-26 13:26:22 +11002146}
2147
2148static void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002149channel_post_mux_client_read(struct ssh *ssh, Channel *c,
2150 fd_set *readset, fd_set *writeset)
Damien Millere1537f92010-01-26 13:26:22 +11002151{
2152 u_int need;
Damien Millere1537f92010-01-26 13:26:22 +11002153
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002154 if (c->rfd == -1 || !FD_ISSET(c->rfd, readset))
2155 return;
2156 if (c->istate != CHAN_INPUT_OPEN && c->istate != CHAN_INPUT_WAIT_DRAIN)
2157 return;
2158 if (c->mux_pause)
2159 return;
2160
2161 /*
2162 * Don't not read past the precise end of packets to
2163 * avoid disrupting fd passing.
2164 */
2165 if (read_mux(ssh, c, 4) < 4) /* read header */
2166 return;
2167 /* XXX sshbuf_peek_u32 */
2168 need = PEEK_U32(sshbuf_ptr(c->input));
Damien Millere1537f92010-01-26 13:26:22 +11002169#define CHANNEL_MUX_MAX_PACKET (256 * 1024)
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002170 if (need > CHANNEL_MUX_MAX_PACKET) {
2171 debug2("channel %d: packet too big %u > %u",
2172 c->self, CHANNEL_MUX_MAX_PACKET, need);
2173 chan_rcvd_oclose(ssh, c);
2174 return;
Damien Millere1537f92010-01-26 13:26:22 +11002175 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002176 if (read_mux(ssh, c, need + 4) < need + 4) /* read body */
2177 return;
2178 if (c->mux_rcb(ssh, c) != 0) {
2179 debug("channel %d: mux_rcb failed", c->self);
2180 chan_mark_dead(ssh, c);
2181 return;
Damien Millere1537f92010-01-26 13:26:22 +11002182 }
2183}
2184
2185static void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002186channel_post_mux_client_write(struct ssh *ssh, Channel *c,
2187 fd_set *readset, fd_set *writeset)
2188{
2189 ssize_t len;
2190 int r;
2191
2192 if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
2193 sshbuf_len(c->output) == 0)
2194 return;
2195
2196 len = write(c->wfd, sshbuf_ptr(c->output), sshbuf_len(c->output));
2197 if (len < 0 && (errno == EINTR || errno == EAGAIN))
2198 return;
2199 if (len <= 0) {
2200 chan_mark_dead(ssh, c);
2201 return;
2202 }
2203 if ((r = sshbuf_consume(c->output, len)) != 0)
2204 fatal("%s: channel %d: consume: %s", __func__,
2205 c->self, ssh_err(r));
2206}
2207
2208static void
2209channel_post_mux_client(struct ssh *ssh, Channel *c,
2210 fd_set *readset, fd_set *writeset)
2211{
2212 channel_post_mux_client_read(ssh, c, readset, writeset);
2213 channel_post_mux_client_write(ssh, c, readset, writeset);
2214}
2215
2216static void
2217channel_post_mux_listener(struct ssh *ssh, Channel *c,
2218 fd_set *readset, fd_set *writeset)
Damien Millere1537f92010-01-26 13:26:22 +11002219{
2220 Channel *nc;
2221 struct sockaddr_storage addr;
2222 socklen_t addrlen;
2223 int newsock;
2224 uid_t euid;
2225 gid_t egid;
2226
2227 if (!FD_ISSET(c->sock, readset))
2228 return;
2229
2230 debug("multiplexing control connection");
2231
2232 /*
2233 * Accept connection on control socket
2234 */
2235 memset(&addr, 0, sizeof(addr));
2236 addrlen = sizeof(addr);
2237 if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
2238 &addrlen)) == -1) {
2239 error("%s accept: %s", __func__, strerror(errno));
Damien Millera6508752012-04-22 11:21:10 +10002240 if (errno == EMFILE || errno == ENFILE)
Darren Tuckerb759c9c2013-06-02 07:46:16 +10002241 c->notbefore = monotime() + 1;
Damien Millere1537f92010-01-26 13:26:22 +11002242 return;
2243 }
2244
2245 if (getpeereid(newsock, &euid, &egid) < 0) {
2246 error("%s getpeereid failed: %s", __func__,
2247 strerror(errno));
2248 close(newsock);
2249 return;
2250 }
2251 if ((euid != 0) && (getuid() != euid)) {
2252 error("multiplex uid mismatch: peer euid %u != uid %u",
2253 (u_int)euid, (u_int)getuid());
2254 close(newsock);
2255 return;
2256 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002257 nc = channel_new(ssh, "multiplex client", SSH_CHANNEL_MUX_CLIENT,
Damien Millere1537f92010-01-26 13:26:22 +11002258 newsock, newsock, -1, c->local_window_max,
2259 c->local_maxpacket, 0, "mux-control", 1);
2260 nc->mux_rcb = c->mux_rcb;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002261 debug3("%s: new mux channel %d fd %d", __func__, nc->self, nc->sock);
Damien Millere1537f92010-01-26 13:26:22 +11002262 /* establish state */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002263 nc->mux_rcb(ssh, nc);
Damien Millere1537f92010-01-26 13:26:22 +11002264 /* mux state transitions must not elicit protocol messages */
2265 nc->flags |= CHAN_LOCAL;
2266}
2267
Ben Lindstrombba81212001-06-25 05:01:22 +00002268static void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002269channel_handler_init(struct ssh_channels *sc)
Damien Millerb38eff82000-04-01 11:09:21 +10002270{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002271 chan_fn **pre, **post;
Ben Lindstrom8b2eecd2002-07-07 22:11:51 +00002272
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002273 if ((pre = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*pre))) == NULL ||
2274 (post = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*post))) == NULL)
2275 fatal("%s: allocation failed", __func__);
Damien Miller33b13562000-04-04 14:38:59 +10002276
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002277 pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
2278 pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
2279 pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2280 pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
2281 pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
2282 pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
2283 pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2284 pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
2285 pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
2286 pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
markus@openbsd.org609d7a62017-09-21 19:16:53 +00002287 pre[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_pre_connecting;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002288 pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
2289 pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
2290
2291 post[SSH_CHANNEL_OPEN] = &channel_post_open;
2292 post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2293 post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
2294 post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
2295 post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
2296 post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2297 post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2298 post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
2299 post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
markus@openbsd.org609d7a62017-09-21 19:16:53 +00002300 post[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_post_connecting;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002301 post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
2302 post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
2303
2304 sc->channel_pre = pre;
2305 sc->channel_post = post;
Damien Miller33b13562000-04-04 14:38:59 +10002306}
2307
Damien Miller3ec27592001-10-12 11:35:04 +10002308/* gc dead channels */
2309static void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002310channel_garbage_collect(struct ssh *ssh, Channel *c)
Damien Miller3ec27592001-10-12 11:35:04 +10002311{
2312 if (c == NULL)
2313 return;
2314 if (c->detach_user != NULL) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002315 if (!chan_is_dead(ssh, c, c->detach_close))
Damien Miller3ec27592001-10-12 11:35:04 +10002316 return;
Damien Millerfbdeece2003-09-02 22:52:31 +10002317 debug2("channel %d: gc: notify user", c->self);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002318 c->detach_user(ssh, c->self, NULL);
Damien Miller3ec27592001-10-12 11:35:04 +10002319 /* if we still have a callback */
2320 if (c->detach_user != NULL)
2321 return;
Damien Millerfbdeece2003-09-02 22:52:31 +10002322 debug2("channel %d: gc: user detached", c->self);
Damien Miller3ec27592001-10-12 11:35:04 +10002323 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002324 if (!chan_is_dead(ssh, c, 1))
Damien Miller3ec27592001-10-12 11:35:04 +10002325 return;
Damien Millerfbdeece2003-09-02 22:52:31 +10002326 debug2("channel %d: garbage collecting", c->self);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002327 channel_free(ssh, c);
Damien Miller3ec27592001-10-12 11:35:04 +10002328}
2329
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002330enum channel_table { CHAN_PRE, CHAN_POST };
2331
Ben Lindstrombba81212001-06-25 05:01:22 +00002332static void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002333channel_handler(struct ssh *ssh, int table,
djm@openbsd.org71e5a532017-08-30 03:59:08 +00002334 fd_set *readset, fd_set *writeset, time_t *unpause_secs)
Damien Millerb38eff82000-04-01 11:09:21 +10002335{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002336 struct ssh_channels *sc = ssh->chanctxt;
2337 chan_fn **ftab = table == CHAN_PRE ? sc->channel_pre : sc->channel_post;
Darren Tucker876045b2010-01-08 17:08:00 +11002338 u_int i, oalloc;
Damien Millerb38eff82000-04-01 11:09:21 +10002339 Channel *c;
Damien Millera6508752012-04-22 11:21:10 +10002340 time_t now;
Damien Millerb38eff82000-04-01 11:09:21 +10002341
Darren Tuckerb759c9c2013-06-02 07:46:16 +10002342 now = monotime();
Damien Millera6508752012-04-22 11:21:10 +10002343 if (unpause_secs != NULL)
2344 *unpause_secs = 0;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002345 for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2346 c = sc->channels[i];
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002347 if (c == NULL)
Damien Millerb38eff82000-04-01 11:09:21 +10002348 continue;
Darren Tucker876045b2010-01-08 17:08:00 +11002349 if (c->delayed) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002350 if (table == CHAN_PRE)
Darren Tucker876045b2010-01-08 17:08:00 +11002351 c->delayed = 0;
2352 else
2353 continue;
2354 }
Damien Millera6508752012-04-22 11:21:10 +10002355 if (ftab[c->type] != NULL) {
2356 /*
2357 * Run handlers that are not paused.
2358 */
2359 if (c->notbefore <= now)
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002360 (*ftab[c->type])(ssh, c, readset, writeset);
Damien Millera6508752012-04-22 11:21:10 +10002361 else if (unpause_secs != NULL) {
2362 /*
2363 * Collect the time that the earliest
2364 * channel comes off pause.
2365 */
2366 debug3("%s: chan %d: skip for %d more seconds",
2367 __func__, c->self,
2368 (int)(c->notbefore - now));
2369 if (*unpause_secs == 0 ||
2370 (c->notbefore - now) < *unpause_secs)
2371 *unpause_secs = c->notbefore - now;
2372 }
2373 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002374 channel_garbage_collect(ssh, c);
Damien Millerb38eff82000-04-01 11:09:21 +10002375 }
Damien Millera6508752012-04-22 11:21:10 +10002376 if (unpause_secs != NULL && *unpause_secs != 0)
2377 debug3("%s: first channel unpauses in %d seconds",
2378 __func__, (int)*unpause_secs);
Damien Millerb38eff82000-04-01 11:09:21 +10002379}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002380
Ben Lindstrome9c99912001-06-09 00:41:05 +00002381/*
markus@openbsd.org609d7a62017-09-21 19:16:53 +00002382 * Create sockets before allocating the select bitmasks.
2383 * This is necessary for things that need to happen after reading
2384 * the network-input but before channel_prepare_select().
2385 */
2386static void
2387channel_before_prepare_select(struct ssh *ssh)
2388{
2389 struct ssh_channels *sc = ssh->chanctxt;
2390 Channel *c;
2391 u_int i, oalloc;
2392
2393 for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2394 c = sc->channels[i];
2395 if (c == NULL)
2396 continue;
2397 if (c->type == SSH_CHANNEL_RDYNAMIC_OPEN)
2398 channel_before_prepare_select_rdynamic(ssh, c);
2399 }
2400}
2401
2402/*
Ben Lindstrome9c99912001-06-09 00:41:05 +00002403 * Allocate/update select bitmasks and add any bits relevant to channels in
2404 * select bitmasks.
2405 */
Damien Miller4af51302000-04-16 11:18:38 +10002406void
djm@openbsd.org71e5a532017-08-30 03:59:08 +00002407channel_prepare_select(struct ssh *ssh, fd_set **readsetp, fd_set **writesetp,
2408 int *maxfdp, u_int *nallocp, time_t *minwait_secs)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002409{
Damien Miller36812092006-03-26 14:22:47 +11002410 u_int n, sz, nfdset;
Damien Miller5e953212001-01-30 09:14:00 +11002411
markus@openbsd.org609d7a62017-09-21 19:16:53 +00002412 channel_before_prepare_select(ssh); /* might update channel_max_fd */
2413
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002414 n = MAXIMUM(*maxfdp, ssh->chanctxt->channel_max_fd);
Damien Miller5e953212001-01-30 09:14:00 +11002415
Damien Miller36812092006-03-26 14:22:47 +11002416 nfdset = howmany(n+1, NFDBITS);
2417 /* Explicitly test here, because xrealloc isn't always called */
millert@openbsd.orgfd368342015-02-06 23:21:59 +00002418 if (nfdset && SIZE_MAX / nfdset < sizeof(fd_mask))
Damien Miller36812092006-03-26 14:22:47 +11002419 fatal("channel_prepare_select: max_fd (%d) is too large", n);
2420 sz = nfdset * sizeof(fd_mask);
2421
Ben Lindstrom16d29d52001-07-18 16:01:46 +00002422 /* perhaps check sz < nalloc/2 and shrink? */
2423 if (*readsetp == NULL || sz > *nallocp) {
deraadt@openbsd.org657a5fb2015-04-24 01:36:00 +00002424 *readsetp = xreallocarray(*readsetp, nfdset, sizeof(fd_mask));
2425 *writesetp = xreallocarray(*writesetp, nfdset, sizeof(fd_mask));
Ben Lindstrom16d29d52001-07-18 16:01:46 +00002426 *nallocp = sz;
Damien Miller5e953212001-01-30 09:14:00 +11002427 }
Ben Lindstrom16d29d52001-07-18 16:01:46 +00002428 *maxfdp = n;
Damien Miller5e953212001-01-30 09:14:00 +11002429 memset(*readsetp, 0, sz);
2430 memset(*writesetp, 0, sz);
2431
djm@openbsd.org71e5a532017-08-30 03:59:08 +00002432 if (!ssh_packet_is_rekeying(ssh))
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002433 channel_handler(ssh, CHAN_PRE, *readsetp, *writesetp,
Damien Millera6508752012-04-22 11:21:10 +10002434 minwait_secs);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002435}
2436
Ben Lindstrome9c99912001-06-09 00:41:05 +00002437/*
2438 * After select, perform any appropriate operations for channels which have
2439 * events pending.
2440 */
Damien Miller4af51302000-04-16 11:18:38 +10002441void
djm@openbsd.org71e5a532017-08-30 03:59:08 +00002442channel_after_select(struct ssh *ssh, fd_set *readset, fd_set *writeset)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002443{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002444 channel_handler(ssh, CHAN_POST, readset, writeset, NULL);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002445}
2446
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002447/*
2448 * Enqueue data for channels with open or draining c->input.
2449 */
2450static void
2451channel_output_poll_input_open(struct ssh *ssh, Channel *c)
2452{
djm@openbsd.org55486f52017-09-23 22:04:07 +00002453 size_t len, plen;
2454 const u_char *pkt;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002455 int r;
2456
2457 if ((len = sshbuf_len(c->input)) == 0) {
2458 if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
2459 /*
2460 * input-buffer is empty and read-socket shutdown:
2461 * tell peer, that we will not send more data:
2462 * send IEOF.
2463 * hack for extended data: delay EOF if EFD still
2464 * in use.
2465 */
2466 if (CHANNEL_EFD_INPUT_ACTIVE(c))
2467 debug2("channel %d: "
2468 "ibuf_empty delayed efd %d/(%zu)",
2469 c->self, c->efd, sshbuf_len(c->extended));
2470 else
2471 chan_ibuf_empty(ssh, c);
2472 }
2473 return;
2474 }
2475
djm@openbsd.org9f532292017-09-12 06:35:31 +00002476 if (!c->have_remote_id)
2477 fatal(":%s: channel %d: no remote id", __func__, c->self);
2478
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002479 if (c->datagram) {
2480 /* Check datagram will fit; drop if not */
djm@openbsd.org55486f52017-09-23 22:04:07 +00002481 if ((r = sshbuf_get_string_direct(c->input, &pkt, &plen)) != 0)
2482 fatal("%s: channel %d: get datagram: %s", __func__,
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002483 c->self, ssh_err(r));
2484 /*
2485 * XXX this does tail-drop on the datagram queue which is
2486 * usually suboptimal compared to head-drop. Better to have
2487 * backpressure at read time? (i.e. read + discard)
2488 */
djm@openbsd.org55486f52017-09-23 22:04:07 +00002489 if (plen > c->remote_window || plen > c->remote_maxpacket) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002490 debug("channel %d: datagram too big", c->self);
2491 return;
2492 }
2493 /* Enqueue it */
2494 if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2495 (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
djm@openbsd.org55486f52017-09-23 22:04:07 +00002496 (r = sshpkt_put_string(ssh, pkt, plen)) != 0 ||
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002497 (r = sshpkt_send(ssh)) != 0) {
2498 fatal("%s: channel %i: datagram: %s", __func__,
2499 c->self, ssh_err(r));
2500 }
djm@openbsd.org55486f52017-09-23 22:04:07 +00002501 c->remote_window -= plen;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002502 return;
2503 }
2504
2505 /* Enqueue packet for buffered data. */
2506 if (len > c->remote_window)
2507 len = c->remote_window;
2508 if (len > c->remote_maxpacket)
2509 len = c->remote_maxpacket;
2510 if (len == 0)
2511 return;
2512 if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2513 (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2514 (r = sshpkt_put_string(ssh, sshbuf_ptr(c->input), len)) != 0 ||
2515 (r = sshpkt_send(ssh)) != 0) {
2516 fatal("%s: channel %i: data: %s", __func__,
2517 c->self, ssh_err(r));
2518 }
2519 if ((r = sshbuf_consume(c->input, len)) != 0)
2520 fatal("%s: channel %i: consume: %s", __func__,
2521 c->self, ssh_err(r));
2522 c->remote_window -= len;
2523}
2524
2525/*
2526 * Enqueue data for channels with open c->extended in read mode.
2527 */
2528static void
2529channel_output_poll_extended_read(struct ssh *ssh, Channel *c)
2530{
2531 size_t len;
2532 int r;
2533
2534 if ((len = sshbuf_len(c->extended)) == 0)
2535 return;
2536
2537 debug2("channel %d: rwin %u elen %zu euse %d", c->self,
2538 c->remote_window, sshbuf_len(c->extended), c->extended_usage);
2539 if (len > c->remote_window)
2540 len = c->remote_window;
2541 if (len > c->remote_maxpacket)
2542 len = c->remote_maxpacket;
2543 if (len == 0)
2544 return;
djm@openbsd.org9f532292017-09-12 06:35:31 +00002545 if (!c->have_remote_id)
2546 fatal(":%s: channel %d: no remote id", __func__, c->self);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002547 if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_EXTENDED_DATA)) != 0 ||
2548 (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2549 (r = sshpkt_put_u32(ssh, SSH2_EXTENDED_DATA_STDERR)) != 0 ||
2550 (r = sshpkt_put_string(ssh, sshbuf_ptr(c->extended), len)) != 0 ||
2551 (r = sshpkt_send(ssh)) != 0) {
2552 fatal("%s: channel %i: data: %s", __func__,
2553 c->self, ssh_err(r));
2554 }
2555 if ((r = sshbuf_consume(c->extended, len)) != 0)
2556 fatal("%s: channel %i: consume: %s", __func__,
2557 c->self, ssh_err(r));
2558 c->remote_window -= len;
2559 debug2("channel %d: sent ext data %zu", c->self, len);
2560}
Ben Lindstrome9c99912001-06-09 00:41:05 +00002561
Damien Miller5e953212001-01-30 09:14:00 +11002562/* If there is data to send to the connection, enqueue some of it now. */
Damien Miller4af51302000-04-16 11:18:38 +10002563void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002564channel_output_poll(struct ssh *ssh)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002565{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002566 struct ssh_channels *sc = ssh->chanctxt;
Damien Millerb38eff82000-04-01 11:09:21 +10002567 Channel *c;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002568 u_int i;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002569
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002570 for (i = 0; i < sc->channels_alloc; i++) {
2571 c = sc->channels[i];
Ben Lindstrom99c73b32001-05-05 04:09:47 +00002572 if (c == NULL)
2573 continue;
Damien Miller34132e52000-01-14 15:45:46 +11002574
Ben Lindstrome9c99912001-06-09 00:41:05 +00002575 /*
2576 * We are only interested in channels that can have buffered
2577 * incoming data.
2578 */
djm@openbsd.org97f4d302017-04-30 23:13:25 +00002579 if (c->type != SSH_CHANNEL_OPEN)
2580 continue;
2581 if ((c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
Ben Lindstrom7fbd4552001-03-05 06:16:11 +00002582 /* XXX is this true? */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002583 debug3("channel %d: will not send data after close",
2584 c->self);
Damien Miller33b13562000-04-04 14:38:59 +10002585 continue;
2586 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002587
Damien Miller95def091999-11-25 00:26:21 +11002588 /* Get the amount of buffered data for this channel. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002589 if (c->istate == CHAN_INPUT_OPEN ||
2590 c->istate == CHAN_INPUT_WAIT_DRAIN)
2591 channel_output_poll_input_open(ssh, c);
Damien Miller33b13562000-04-04 14:38:59 +10002592 /* Send extended data, i.e. stderr */
djm@openbsd.org97f4d302017-04-30 23:13:25 +00002593 if (!(c->flags & CHAN_EOF_SENT) &&
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002594 c->extended_usage == CHAN_EXTENDED_READ)
2595 channel_output_poll_extended_read(ssh, c);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002596 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002597}
2598
markus@openbsd.org8d057842016-09-30 09:19:13 +00002599/* -- mux proxy support */
2600
2601/*
2602 * When multiplexing channel messages for mux clients we have to deal
2603 * with downstream messages from the mux client and upstream messages
2604 * from the ssh server:
2605 * 1) Handling downstream messages is straightforward and happens
2606 * in channel_proxy_downstream():
2607 * - We forward all messages (mostly) unmodified to the server.
2608 * - However, in order to route messages from upstream to the correct
2609 * downstream client, we have to replace the channel IDs used by the
2610 * mux clients with a unique channel ID because the mux clients might
2611 * use conflicting channel IDs.
2612 * - so we inspect and change both SSH2_MSG_CHANNEL_OPEN and
2613 * SSH2_MSG_CHANNEL_OPEN_CONFIRMATION messages, create a local
2614 * SSH_CHANNEL_MUX_PROXY channel and replace the mux clients ID
2615 * with the newly allocated channel ID.
2616 * 2) Upstream messages are received by matching SSH_CHANNEL_MUX_PROXY
2617 * channels and procesed by channel_proxy_upstream(). The local channel ID
2618 * is then translated back to the original mux client ID.
2619 * 3) In both cases we need to keep track of matching SSH2_MSG_CHANNEL_CLOSE
2620 * messages so we can clean up SSH_CHANNEL_MUX_PROXY channels.
2621 * 4) The SSH_CHANNEL_MUX_PROXY channels also need to closed when the
2622 * downstream mux client are removed.
2623 * 5) Handling SSH2_MSG_CHANNEL_OPEN messages from the upstream server
2624 * requires more work, because they are not addressed to a specific
2625 * channel. E.g. client_request_forwarded_tcpip() needs to figure
2626 * out whether the request is addressed to the local client or a
2627 * specific downstream client based on the listen-address/port.
2628 * 6) Agent and X11-Forwarding have a similar problem and are currenly
2629 * not supported as the matching session/channel cannot be identified
2630 * easily.
2631 */
2632
2633/*
2634 * receive packets from downstream mux clients:
2635 * channel callback fired on read from mux client, creates
2636 * SSH_CHANNEL_MUX_PROXY channels and translates channel IDs
2637 * on channel creation.
2638 */
2639int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002640channel_proxy_downstream(struct ssh *ssh, Channel *downstream)
markus@openbsd.org8d057842016-09-30 09:19:13 +00002641{
2642 Channel *c = NULL;
markus@openbsd.org8d057842016-09-30 09:19:13 +00002643 struct sshbuf *original = NULL, *modified = NULL;
2644 const u_char *cp;
2645 char *ctype = NULL, *listen_host = NULL;
2646 u_char type;
2647 size_t have;
djm@openbsd.org4ec0bb92017-09-12 07:55:48 +00002648 int ret = -1, r;
djm@openbsd.org2f78a2a2016-09-30 20:24:46 +00002649 u_int id, remote_id, listen_port;
markus@openbsd.org8d057842016-09-30 09:19:13 +00002650
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002651 /* sshbuf_dump(downstream->input, stderr); */
2652 if ((r = sshbuf_get_string_direct(downstream->input, &cp, &have))
markus@openbsd.org8d057842016-09-30 09:19:13 +00002653 != 0) {
2654 error("%s: malformed message: %s", __func__, ssh_err(r));
2655 return -1;
2656 }
2657 if (have < 2) {
2658 error("%s: short message", __func__);
2659 return -1;
2660 }
2661 type = cp[1];
2662 /* skip padlen + type */
2663 cp += 2;
2664 have -= 2;
2665 if (ssh_packet_log_type(type))
2666 debug3("%s: channel %u: down->up: type %u", __func__,
2667 downstream->self, type);
2668
2669 switch (type) {
2670 case SSH2_MSG_CHANNEL_OPEN:
2671 if ((original = sshbuf_from(cp, have)) == NULL ||
2672 (modified = sshbuf_new()) == NULL) {
2673 error("%s: alloc", __func__);
2674 goto out;
2675 }
2676 if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0 ||
2677 (r = sshbuf_get_u32(original, &id)) != 0) {
2678 error("%s: parse error %s", __func__, ssh_err(r));
2679 goto out;
2680 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002681 c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
markus@openbsd.org8d057842016-09-30 09:19:13 +00002682 -1, -1, -1, 0, 0, 0, ctype, 1);
2683 c->mux_ctx = downstream; /* point to mux client */
2684 c->mux_downstream_id = id; /* original downstream id */
2685 if ((r = sshbuf_put_cstring(modified, ctype)) != 0 ||
2686 (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2687 (r = sshbuf_putb(modified, original)) != 0) {
2688 error("%s: compose error %s", __func__, ssh_err(r));
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002689 channel_free(ssh, c);
markus@openbsd.org8d057842016-09-30 09:19:13 +00002690 goto out;
2691 }
2692 break;
2693 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2694 /*
2695 * Almost the same as SSH2_MSG_CHANNEL_OPEN, except then we
2696 * need to parse 'remote_id' instead of 'ctype'.
2697 */
2698 if ((original = sshbuf_from(cp, have)) == NULL ||
2699 (modified = sshbuf_new()) == NULL) {
2700 error("%s: alloc", __func__);
2701 goto out;
2702 }
2703 if ((r = sshbuf_get_u32(original, &remote_id)) != 0 ||
2704 (r = sshbuf_get_u32(original, &id)) != 0) {
2705 error("%s: parse error %s", __func__, ssh_err(r));
2706 goto out;
2707 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002708 c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
markus@openbsd.org8d057842016-09-30 09:19:13 +00002709 -1, -1, -1, 0, 0, 0, "mux-down-connect", 1);
2710 c->mux_ctx = downstream; /* point to mux client */
2711 c->mux_downstream_id = id;
2712 c->remote_id = remote_id;
djm@openbsd.org9f532292017-09-12 06:35:31 +00002713 c->have_remote_id = 1;
markus@openbsd.org8d057842016-09-30 09:19:13 +00002714 if ((r = sshbuf_put_u32(modified, remote_id)) != 0 ||
2715 (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2716 (r = sshbuf_putb(modified, original)) != 0) {
2717 error("%s: compose error %s", __func__, ssh_err(r));
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002718 channel_free(ssh, c);
markus@openbsd.org8d057842016-09-30 09:19:13 +00002719 goto out;
2720 }
2721 break;
2722 case SSH2_MSG_GLOBAL_REQUEST:
2723 if ((original = sshbuf_from(cp, have)) == NULL) {
2724 error("%s: alloc", __func__);
2725 goto out;
2726 }
2727 if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0) {
2728 error("%s: parse error %s", __func__, ssh_err(r));
2729 goto out;
2730 }
2731 if (strcmp(ctype, "tcpip-forward") != 0) {
2732 error("%s: unsupported request %s", __func__, ctype);
2733 goto out;
2734 }
2735 if ((r = sshbuf_get_u8(original, NULL)) != 0 ||
2736 (r = sshbuf_get_cstring(original, &listen_host, NULL)) != 0 ||
2737 (r = sshbuf_get_u32(original, &listen_port)) != 0) {
2738 error("%s: parse error %s", __func__, ssh_err(r));
2739 goto out;
2740 }
djm@openbsd.org2f78a2a2016-09-30 20:24:46 +00002741 if (listen_port > 65535) {
2742 error("%s: tcpip-forward for %s: bad port %u",
2743 __func__, listen_host, listen_port);
2744 goto out;
2745 }
markus@openbsd.org8d057842016-09-30 09:19:13 +00002746 /* Record that connection to this host/port is permitted. */
djm@openbsd.org4ec0bb92017-09-12 07:55:48 +00002747 fwd_perm_list_add(ssh, FWDPERM_USER, "<mux>", -1,
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002748 listen_host, NULL, (int)listen_port, downstream);
markus@openbsd.org8d057842016-09-30 09:19:13 +00002749 listen_host = NULL;
2750 break;
2751 case SSH2_MSG_CHANNEL_CLOSE:
2752 if (have < 4)
2753 break;
2754 remote_id = PEEK_U32(cp);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002755 if ((c = channel_by_remote_id(ssh, remote_id)) != NULL) {
markus@openbsd.org8d057842016-09-30 09:19:13 +00002756 if (c->flags & CHAN_CLOSE_RCVD)
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002757 channel_free(ssh, c);
markus@openbsd.org8d057842016-09-30 09:19:13 +00002758 else
2759 c->flags |= CHAN_CLOSE_SENT;
2760 }
2761 break;
2762 }
2763 if (modified) {
2764 if ((r = sshpkt_start(ssh, type)) != 0 ||
2765 (r = sshpkt_putb(ssh, modified)) != 0 ||
2766 (r = sshpkt_send(ssh)) != 0) {
2767 error("%s: send %s", __func__, ssh_err(r));
2768 goto out;
2769 }
2770 } else {
2771 if ((r = sshpkt_start(ssh, type)) != 0 ||
2772 (r = sshpkt_put(ssh, cp, have)) != 0 ||
2773 (r = sshpkt_send(ssh)) != 0) {
2774 error("%s: send %s", __func__, ssh_err(r));
2775 goto out;
2776 }
2777 }
2778 ret = 0;
2779 out:
2780 free(ctype);
2781 free(listen_host);
2782 sshbuf_free(original);
2783 sshbuf_free(modified);
2784 return ret;
2785}
2786
2787/*
2788 * receive packets from upstream server and de-multiplex packets
2789 * to correct downstream:
2790 * implemented as a helper for channel input handlers,
2791 * replaces local (proxy) channel ID with downstream channel ID.
2792 */
2793int
markus@openbsd.org2ae666a2017-05-30 14:23:52 +00002794channel_proxy_upstream(Channel *c, int type, u_int32_t seq, struct ssh *ssh)
markus@openbsd.org8d057842016-09-30 09:19:13 +00002795{
markus@openbsd.org8d057842016-09-30 09:19:13 +00002796 struct sshbuf *b = NULL;
2797 Channel *downstream;
2798 const u_char *cp = NULL;
2799 size_t len;
2800 int r;
2801
2802 /*
2803 * When receiving packets from the peer we need to check whether we
2804 * need to forward the packets to the mux client. In this case we
2805 * restore the orignal channel id and keep track of CLOSE messages,
2806 * so we can cleanup the channel.
2807 */
2808 if (c == NULL || c->type != SSH_CHANNEL_MUX_PROXY)
2809 return 0;
2810 if ((downstream = c->mux_ctx) == NULL)
2811 return 0;
2812 switch (type) {
2813 case SSH2_MSG_CHANNEL_CLOSE:
2814 case SSH2_MSG_CHANNEL_DATA:
2815 case SSH2_MSG_CHANNEL_EOF:
2816 case SSH2_MSG_CHANNEL_EXTENDED_DATA:
2817 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2818 case SSH2_MSG_CHANNEL_OPEN_FAILURE:
2819 case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
2820 case SSH2_MSG_CHANNEL_SUCCESS:
2821 case SSH2_MSG_CHANNEL_FAILURE:
2822 case SSH2_MSG_CHANNEL_REQUEST:
2823 break;
2824 default:
2825 debug2("%s: channel %u: unsupported type %u", __func__,
2826 c->self, type);
2827 return 0;
2828 }
2829 if ((b = sshbuf_new()) == NULL) {
2830 error("%s: alloc reply", __func__);
2831 goto out;
2832 }
2833 /* get remaining payload (after id) */
2834 cp = sshpkt_ptr(ssh, &len);
2835 if (cp == NULL) {
2836 error("%s: no packet", __func__);
2837 goto out;
2838 }
2839 /* translate id and send to muxclient */
2840 if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */
2841 (r = sshbuf_put_u8(b, type)) != 0 ||
2842 (r = sshbuf_put_u32(b, c->mux_downstream_id)) != 0 ||
2843 (r = sshbuf_put(b, cp, len)) != 0 ||
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002844 (r = sshbuf_put_stringb(downstream->output, b)) != 0) {
markus@openbsd.org8d057842016-09-30 09:19:13 +00002845 error("%s: compose for muxclient %s", __func__, ssh_err(r));
2846 goto out;
2847 }
2848 /* sshbuf_dump(b, stderr); */
2849 if (ssh_packet_log_type(type))
2850 debug3("%s: channel %u: up->down: type %u", __func__, c->self,
2851 type);
2852 out:
2853 /* update state */
2854 switch (type) {
2855 case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2856 /* record remote_id for SSH2_MSG_CHANNEL_CLOSE */
djm@openbsd.org9f532292017-09-12 06:35:31 +00002857 if (cp && len > 4) {
markus@openbsd.org8d057842016-09-30 09:19:13 +00002858 c->remote_id = PEEK_U32(cp);
djm@openbsd.org9f532292017-09-12 06:35:31 +00002859 c->have_remote_id = 1;
2860 }
markus@openbsd.org8d057842016-09-30 09:19:13 +00002861 break;
2862 case SSH2_MSG_CHANNEL_CLOSE:
2863 if (c->flags & CHAN_CLOSE_SENT)
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002864 channel_free(ssh, c);
markus@openbsd.org8d057842016-09-30 09:19:13 +00002865 else
2866 c->flags |= CHAN_CLOSE_RCVD;
2867 break;
2868 }
2869 sshbuf_free(b);
2870 return 1;
2871}
Ben Lindstrome9c99912001-06-09 00:41:05 +00002872
2873/* -- protocol input */
Damien Millerd79b4242006-03-31 23:11:44 +11002874
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002875/* Parse a channel ID from the current packet */
2876static int
2877channel_parse_id(struct ssh *ssh, const char *where, const char *what)
2878{
2879 u_int32_t id;
2880 int r;
2881
2882 if ((r = sshpkt_get_u32(ssh, &id)) != 0) {
2883 error("%s: parse id: %s", where, ssh_err(r));
2884 ssh_packet_disconnect(ssh, "Invalid %s message", what);
2885 }
2886 if (id > INT_MAX) {
2887 error("%s: bad channel id %u: %s", where, id, ssh_err(r));
2888 ssh_packet_disconnect(ssh, "Invalid %s channel id", what);
2889 }
2890 return (int)id;
2891}
2892
2893/* Lookup a channel from an ID in the current packet */
2894static Channel *
2895channel_from_packet_id(struct ssh *ssh, const char *where, const char *what)
2896{
2897 int id = channel_parse_id(ssh, where, what);
2898 Channel *c;
2899
2900 if ((c = channel_lookup(ssh, id)) == NULL) {
2901 ssh_packet_disconnect(ssh,
2902 "%s packet referred to nonexistent channel %d", what, id);
2903 }
2904 return c;
2905}
2906
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00002907int
markus@openbsd.org2ae666a2017-05-30 14:23:52 +00002908channel_input_data(int type, u_int32_t seq, struct ssh *ssh)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002909{
Damien Miller633de332014-05-15 13:48:26 +10002910 const u_char *data;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002911 size_t data_len, win_len;
2912 Channel *c = channel_from_packet_id(ssh, __func__, "data");
2913 int r;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002914
markus@openbsd.org2ae666a2017-05-30 14:23:52 +00002915 if (channel_proxy_upstream(c, type, seq, ssh))
markus@openbsd.org8d057842016-09-30 09:19:13 +00002916 return 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002917
Damien Miller95def091999-11-25 00:26:21 +11002918 /* Ignore any data for non-open channels (might happen on close) */
Damien Millerb38eff82000-04-01 11:09:21 +10002919 if (c->type != SSH_CHANNEL_OPEN &&
markus@openbsd.org609d7a62017-09-21 19:16:53 +00002920 c->type != SSH_CHANNEL_RDYNAMIC_OPEN &&
2921 c->type != SSH_CHANNEL_RDYNAMIC_FINISH &&
Damien Millerb38eff82000-04-01 11:09:21 +10002922 c->type != SSH_CHANNEL_X11_OPEN)
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00002923 return 0;
Damien Miller34132e52000-01-14 15:45:46 +11002924
Damien Miller95def091999-11-25 00:26:21 +11002925 /* Get the data. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002926 if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0)
2927 fatal("%s: channel %d: get data: %s", __func__,
2928 c->self, ssh_err(r));
2929 ssh_packet_check_eom(ssh);
2930
Damien Miller7d457182010-08-05 23:09:48 +10002931 win_len = data_len;
2932 if (c->datagram)
2933 win_len += 4; /* string length header */
Damien Millerb38eff82000-04-01 11:09:21 +10002934
Damien Millera04ad492004-01-21 11:02:09 +11002935 /*
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002936 * The sending side reduces its window as it sends data, so we
2937 * must 'fake' consumption of the data in order to ensure that window
2938 * updates are sent back. Otherwise the connection might deadlock.
Damien Millera04ad492004-01-21 11:02:09 +11002939 */
djm@openbsd.org97f4d302017-04-30 23:13:25 +00002940 if (c->ostate != CHAN_OUTPUT_OPEN) {
2941 c->local_window -= win_len;
2942 c->local_consumed += win_len;
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00002943 return 0;
Damien Millera04ad492004-01-21 11:02:09 +11002944 }
2945
djm@openbsd.org97f4d302017-04-30 23:13:25 +00002946 if (win_len > c->local_maxpacket) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002947 logit("channel %d: rcvd big packet %zu, maxpack %u",
djm@openbsd.org97f4d302017-04-30 23:13:25 +00002948 c->self, win_len, c->local_maxpacket);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002949 return 0;
Damien Miller33b13562000-04-04 14:38:59 +10002950 }
djm@openbsd.org97f4d302017-04-30 23:13:25 +00002951 if (win_len > c->local_window) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002952 logit("channel %d: rcvd too much data %zu, win %u",
djm@openbsd.org97f4d302017-04-30 23:13:25 +00002953 c->self, win_len, c->local_window);
2954 return 0;
2955 }
2956 c->local_window -= win_len;
2957
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002958 if (c->datagram) {
2959 if ((r = sshbuf_put_string(c->output, data, data_len)) != 0)
2960 fatal("%s: channel %d: append datagram: %s",
2961 __func__, c->self, ssh_err(r));
2962 } else if ((r = sshbuf_put(c->output, data, data_len)) != 0)
2963 fatal("%s: channel %d: append data: %s",
2964 __func__, c->self, ssh_err(r));
2965
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00002966 return 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002967}
Ben Lindstrome9c99912001-06-09 00:41:05 +00002968
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00002969int
markus@openbsd.org2ae666a2017-05-30 14:23:52 +00002970channel_input_extended_data(int type, u_int32_t seq, struct ssh *ssh)
Damien Miller33b13562000-04-04 14:38:59 +10002971{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002972 const u_char *data;
2973 size_t data_len;
2974 u_int32_t tcode;
2975 Channel *c = channel_from_packet_id(ssh, __func__, "extended data");
2976 int r;
Damien Miller33b13562000-04-04 14:38:59 +10002977
markus@openbsd.org2ae666a2017-05-30 14:23:52 +00002978 if (channel_proxy_upstream(c, type, seq, ssh))
markus@openbsd.org8d057842016-09-30 09:19:13 +00002979 return 0;
Damien Miller33b13562000-04-04 14:38:59 +10002980 if (c->type != SSH_CHANNEL_OPEN) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002981 logit("channel %d: ext data for non open", c->self);
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00002982 return 0;
Damien Miller33b13562000-04-04 14:38:59 +10002983 }
Ben Lindstromcf159442002-03-26 03:26:24 +00002984 if (c->flags & CHAN_EOF_RCVD) {
2985 if (datafellows & SSH_BUG_EXTEOF)
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002986 debug("channel %d: accepting ext data after eof",
2987 c->self);
Ben Lindstromcf159442002-03-26 03:26:24 +00002988 else
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002989 ssh_packet_disconnect(ssh, "Received extended_data "
2990 "after EOF on channel %d.", c->self);
Ben Lindstromcf159442002-03-26 03:26:24 +00002991 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00002992
2993 if ((r = sshpkt_get_u32(ssh, &tcode)) != 0) {
2994 error("%s: parse tcode: %s", __func__, ssh_err(r));
2995 ssh_packet_disconnect(ssh, "Invalid extended_data message");
2996 }
Damien Miller33b13562000-04-04 14:38:59 +10002997 if (c->efd == -1 ||
2998 c->extended_usage != CHAN_EXTENDED_WRITE ||
2999 tcode != SSH2_EXTENDED_DATA_STDERR) {
Damien Miller996acd22003-04-09 20:59:48 +10003000 logit("channel %d: bad ext data", c->self);
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00003001 return 0;
Damien Miller33b13562000-04-04 14:38:59 +10003002 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003003 if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0) {
3004 error("%s: parse data: %s", __func__, ssh_err(r));
3005 ssh_packet_disconnect(ssh, "Invalid extended_data message");
3006 }
3007 ssh_packet_check_eom(ssh);
3008
Damien Miller33b13562000-04-04 14:38:59 +10003009 if (data_len > c->local_window) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003010 logit("channel %d: rcvd too much extended_data %zu, win %u",
Damien Miller33b13562000-04-04 14:38:59 +10003011 c->self, data_len, c->local_window);
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00003012 return 0;
Damien Miller33b13562000-04-04 14:38:59 +10003013 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003014 debug2("channel %d: rcvd ext data %zu", c->self, data_len);
3015 /* XXX sshpkt_getb? */
3016 if ((r = sshbuf_put(c->extended, data, data_len)) != 0)
3017 error("%s: append: %s", __func__, ssh_err(r));
Damien Miller33b13562000-04-04 14:38:59 +10003018 c->local_window -= data_len;
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00003019 return 0;
Damien Miller33b13562000-04-04 14:38:59 +10003020}
3021
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00003022int
markus@openbsd.org2ae666a2017-05-30 14:23:52 +00003023channel_input_ieof(int type, u_int32_t seq, struct ssh *ssh)
Damien Millerb38eff82000-04-01 11:09:21 +10003024{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003025 Channel *c = channel_from_packet_id(ssh, __func__, "ieof");
Damien Millerb38eff82000-04-01 11:09:21 +10003026
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003027 ssh_packet_check_eom(ssh);
3028
markus@openbsd.org2ae666a2017-05-30 14:23:52 +00003029 if (channel_proxy_upstream(c, type, seq, ssh))
markus@openbsd.org8d057842016-09-30 09:19:13 +00003030 return 0;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003031 chan_rcvd_ieof(ssh, c);
Ben Lindstrom944c4f02001-09-18 05:51:13 +00003032
3033 /* XXX force input close */
Damien Millera90fc082002-01-22 23:19:38 +11003034 if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
Ben Lindstrom944c4f02001-09-18 05:51:13 +00003035 debug("channel %d: FORCE input drain", c->self);
3036 c->istate = CHAN_INPUT_WAIT_DRAIN;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003037 if (sshbuf_len(c->input) == 0)
3038 chan_ibuf_empty(ssh, c);
Ben Lindstrom944c4f02001-09-18 05:51:13 +00003039 }
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00003040 return 0;
Damien Millerb38eff82000-04-01 11:09:21 +10003041}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10003042
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00003043int
markus@openbsd.org2ae666a2017-05-30 14:23:52 +00003044channel_input_oclose(int type, u_int32_t seq, struct ssh *ssh)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10003045{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003046 Channel *c = channel_from_packet_id(ssh, __func__, "oclose");
Damien Miller66823cd2002-01-22 23:11:38 +11003047
markus@openbsd.org2ae666a2017-05-30 14:23:52 +00003048 if (channel_proxy_upstream(c, type, seq, ssh))
markus@openbsd.org8d057842016-09-30 09:19:13 +00003049 return 0;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003050 ssh_packet_check_eom(ssh);
3051 chan_rcvd_oclose(ssh, c);
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00003052 return 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10003053}
3054
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00003055int
markus@openbsd.org2ae666a2017-05-30 14:23:52 +00003056channel_input_open_confirmation(int type, u_int32_t seq, struct ssh *ssh)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10003057{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003058 Channel *c = channel_from_packet_id(ssh, __func__, "open confirmation");
3059 u_int32_t remote_window, remote_maxpacket;
3060 int r;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10003061
markus@openbsd.org2ae666a2017-05-30 14:23:52 +00003062 if (channel_proxy_upstream(c, type, seq, ssh))
markus@openbsd.org8d057842016-09-30 09:19:13 +00003063 return 0;
3064 if (c->type != SSH_CHANNEL_OPENING)
Damien Millerb38eff82000-04-01 11:09:21 +10003065 packet_disconnect("Received open confirmation for "
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003066 "non-opening channel %d.", c->self);
3067 /*
3068 * Record the remote channel number and mark that the channel
3069 * is now open.
3070 */
djm@openbsd.org9f532292017-09-12 06:35:31 +00003071 if ((r = sshpkt_get_u32(ssh, &c->remote_id)) != 0 ||
3072 (r = sshpkt_get_u32(ssh, &remote_window)) != 0 ||
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003073 (r = sshpkt_get_u32(ssh, &remote_maxpacket)) != 0) {
3074 error("%s: window/maxpacket: %s", __func__, ssh_err(r));
3075 packet_disconnect("Invalid open confirmation message");
3076 }
3077 ssh_packet_check_eom(ssh);
Damien Miller33b13562000-04-04 14:38:59 +10003078
djm@openbsd.org9f532292017-09-12 06:35:31 +00003079 c->have_remote_id = 1;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003080 c->remote_window = remote_window;
3081 c->remote_maxpacket = remote_maxpacket;
3082 c->type = SSH_CHANNEL_OPEN;
djm@openbsd.org97f4d302017-04-30 23:13:25 +00003083 if (c->open_confirm) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003084 debug2("%s: channel %d: callback start", __func__, c->self);
3085 c->open_confirm(ssh, c->self, 1, c->open_confirm_ctx);
3086 debug2("%s: channel %d: callback done", __func__, c->self);
Damien Miller33b13562000-04-04 14:38:59 +10003087 }
djm@openbsd.org97f4d302017-04-30 23:13:25 +00003088 debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
3089 c->remote_window, c->remote_maxpacket);
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00003090 return 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10003091}
3092
Ben Lindstrombba81212001-06-25 05:01:22 +00003093static char *
Ben Lindstrom69128662001-05-08 20:07:39 +00003094reason2txt(int reason)
3095{
Ben Lindstrom1c37c6a2001-12-06 18:00:18 +00003096 switch (reason) {
Ben Lindstrom69128662001-05-08 20:07:39 +00003097 case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
3098 return "administratively prohibited";
3099 case SSH2_OPEN_CONNECT_FAILED:
3100 return "connect failed";
3101 case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
3102 return "unknown channel type";
3103 case SSH2_OPEN_RESOURCE_SHORTAGE:
3104 return "resource shortage";
3105 }
Ben Lindstrome2595442001-06-05 20:01:39 +00003106 return "unknown reason";
Ben Lindstrom69128662001-05-08 20:07:39 +00003107}
3108
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00003109int
markus@openbsd.org2ae666a2017-05-30 14:23:52 +00003110channel_input_open_failure(int type, u_int32_t seq, struct ssh *ssh)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10003111{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003112 Channel *c = channel_from_packet_id(ssh, __func__, "open failure");
3113 u_int32_t reason;
3114 char *msg = NULL;
3115 int r;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10003116
markus@openbsd.org2ae666a2017-05-30 14:23:52 +00003117 if (channel_proxy_upstream(c, type, seq, ssh))
markus@openbsd.org8d057842016-09-30 09:19:13 +00003118 return 0;
3119 if (c->type != SSH_CHANNEL_OPENING)
Damien Millerb38eff82000-04-01 11:09:21 +10003120 packet_disconnect("Received open failure for "
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003121 "non-opening channel %d.", c->self);
3122 if ((r = sshpkt_get_u32(ssh, &reason)) != 0) {
3123 error("%s: reason: %s", __func__, ssh_err(r));
3124 packet_disconnect("Invalid open failure message");
djm@openbsd.org97f4d302017-04-30 23:13:25 +00003125 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003126 if ((datafellows & SSH_BUG_OPENFAILURE) == 0) {
3127 /* skip language */
3128 if ((r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
djm@openbsd.org218e6f92017-09-24 13:45:34 +00003129 (r = sshpkt_get_string_direct(ssh, NULL, NULL)) != 0) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003130 error("%s: message/lang: %s", __func__, ssh_err(r));
3131 packet_disconnect("Invalid open failure message");
3132 }
3133 }
3134 ssh_packet_check_eom(ssh);
3135 logit("channel %d: open failed: %s%s%s", c->self,
djm@openbsd.org97f4d302017-04-30 23:13:25 +00003136 reason2txt(reason), msg ? ": ": "", msg ? msg : "");
3137 free(msg);
djm@openbsd.org97f4d302017-04-30 23:13:25 +00003138 if (c->open_confirm) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003139 debug2("%s: channel %d: callback start", __func__, c->self);
3140 c->open_confirm(ssh, c->self, 0, c->open_confirm_ctx);
3141 debug2("%s: channel %d: callback done", __func__, c->self);
Damien Miller33b13562000-04-04 14:38:59 +10003142 }
Damien Miller7a606212009-01-28 16:22:34 +11003143 /* Schedule the channel for cleanup/deletion. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003144 chan_mark_dead(ssh, c);
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00003145 return 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10003146}
3147
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00003148int
markus@openbsd.org2ae666a2017-05-30 14:23:52 +00003149channel_input_window_adjust(int type, u_int32_t seq, struct ssh *ssh)
Damien Miller33b13562000-04-04 14:38:59 +10003150{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003151 int id = channel_parse_id(ssh, __func__, "window adjust");
Damien Miller33b13562000-04-04 14:38:59 +10003152 Channel *c;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003153 u_int32_t adjust;
3154 u_int new_rwin;
3155 int r;
Damien Miller33b13562000-04-04 14:38:59 +10003156
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003157 if ((c = channel_lookup(ssh, id)) == NULL) {
Damien Millerd47c62a2005-12-13 19:33:57 +11003158 logit("Received window adjust for non-open channel %d.", id);
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00003159 return 0;
markus@openbsd.org609d7a62017-09-21 19:16:53 +00003160 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003161
markus@openbsd.org2ae666a2017-05-30 14:23:52 +00003162 if (channel_proxy_upstream(c, type, seq, ssh))
markus@openbsd.org8d057842016-09-30 09:19:13 +00003163 return 0;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003164 if ((r = sshpkt_get_u32(ssh, &adjust)) != 0) {
3165 error("%s: adjust: %s", __func__, ssh_err(r));
3166 packet_disconnect("Invalid window adjust message");
3167 }
3168 ssh_packet_check_eom(ssh);
3169 debug2("channel %d: rcvd adjust %u", c->self, adjust);
3170 if ((new_rwin = c->remote_window + adjust) < c->remote_window) {
djm@openbsd.org629df772015-06-30 05:25:07 +00003171 fatal("channel %d: adjust %u overflows remote window %u",
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003172 c->self, adjust, c->remote_window);
3173 }
3174 c->remote_window = new_rwin;
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00003175 return 0;
Damien Miller33b13562000-04-04 14:38:59 +10003176}
3177
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00003178int
markus@openbsd.org2ae666a2017-05-30 14:23:52 +00003179channel_input_status_confirm(int type, u_int32_t seq, struct ssh *ssh)
Damien Millerb84886b2008-05-19 15:05:07 +10003180{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003181 int id = channel_parse_id(ssh, __func__, "status confirm");
Damien Millerb84886b2008-05-19 15:05:07 +10003182 Channel *c;
3183 struct channel_confirm *cc;
Damien Millerb84886b2008-05-19 15:05:07 +10003184
3185 /* Reset keepalive timeout */
Darren Tuckerf7288d72009-06-21 18:12:20 +10003186 packet_set_alive_timeouts(0);
Damien Millerb84886b2008-05-19 15:05:07 +10003187
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003188 debug2("%s: type %d id %d", __func__, type, id);
Damien Millerb84886b2008-05-19 15:05:07 +10003189
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003190 if ((c = channel_lookup(ssh, id)) == NULL) {
3191 logit("%s: %d: unknown", __func__, id);
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00003192 return 0;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003193 }
markus@openbsd.org2ae666a2017-05-30 14:23:52 +00003194 if (channel_proxy_upstream(c, type, seq, ssh))
markus@openbsd.org8d057842016-09-30 09:19:13 +00003195 return 0;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003196 ssh_packet_check_eom(ssh);
Damien Millerb84886b2008-05-19 15:05:07 +10003197 if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00003198 return 0;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003199 cc->cb(ssh, type, c, cc->ctx);
Damien Millerb84886b2008-05-19 15:05:07 +10003200 TAILQ_REMOVE(&c->status_confirms, cc, entry);
Damien Miller1d2c4562014-02-04 11:18:20 +11003201 explicit_bzero(cc, sizeof(*cc));
Darren Tuckera627d422013-06-02 07:31:17 +10003202 free(cc);
markus@openbsd.org3fdc88a2015-01-19 20:07:45 +00003203 return 0;
Damien Millerb84886b2008-05-19 15:05:07 +10003204}
Ben Lindstrom5744dc42001-04-13 23:28:01 +00003205
Ben Lindstrome9c99912001-06-09 00:41:05 +00003206/* -- tcp forwarding */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10003207
Ben Lindstrom908afed2001-10-03 17:34:59 +00003208void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003209channel_set_af(struct ssh *ssh, int af)
Ben Lindstrom908afed2001-10-03 17:34:59 +00003210{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003211 ssh->chanctxt->IPv4or6 = af;
Ben Lindstrom908afed2001-10-03 17:34:59 +00003212}
3213
Damien Millerf6dff7c2011-09-22 21:38:52 +10003214
3215/*
3216 * Determine whether or not a port forward listens to loopback, the
3217 * specified address or wildcard. On the client, a specified bind
3218 * address will always override gateway_ports. On the server, a
3219 * gateway_ports of 1 (``yes'') will override the client's specification
3220 * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
3221 * will bind to whatever address the client asked for.
3222 *
3223 * Special-case listen_addrs are:
3224 *
3225 * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
3226 * "" (empty string), "*" -> wildcard v4/v6
3227 * "localhost" -> loopback v4/v6
Damien Miller602943d2014-07-04 08:59:41 +10003228 * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
Damien Millerf6dff7c2011-09-22 21:38:52 +10003229 */
3230static const char *
3231channel_fwd_bind_addr(const char *listen_addr, int *wildcardp,
Damien Miller7acefbb2014-07-18 14:11:24 +10003232 int is_client, struct ForwardOptions *fwd_opts)
Damien Millerf6dff7c2011-09-22 21:38:52 +10003233{
3234 const char *addr = NULL;
3235 int wildcard = 0;
3236
3237 if (listen_addr == NULL) {
3238 /* No address specified: default to gateway_ports setting */
Damien Miller7acefbb2014-07-18 14:11:24 +10003239 if (fwd_opts->gateway_ports)
Damien Millerf6dff7c2011-09-22 21:38:52 +10003240 wildcard = 1;
Damien Miller7acefbb2014-07-18 14:11:24 +10003241 } else if (fwd_opts->gateway_ports || is_client) {
Damien Millerf6dff7c2011-09-22 21:38:52 +10003242 if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
3243 strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
3244 *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
Damien Miller7acefbb2014-07-18 14:11:24 +10003245 (!is_client && fwd_opts->gateway_ports == 1)) {
Damien Millerf6dff7c2011-09-22 21:38:52 +10003246 wildcard = 1;
Darren Tucker71152bc2013-10-10 10:27:21 +11003247 /*
3248 * Notify client if they requested a specific listen
3249 * address and it was overridden.
3250 */
3251 if (*listen_addr != '\0' &&
3252 strcmp(listen_addr, "0.0.0.0") != 0 &&
3253 strcmp(listen_addr, "*") != 0) {
3254 packet_send_debug("Forwarding listen address "
3255 "\"%s\" overridden by server "
3256 "GatewayPorts", listen_addr);
3257 }
Damien Miller602943d2014-07-04 08:59:41 +10003258 } else if (strcmp(listen_addr, "localhost") != 0 ||
3259 strcmp(listen_addr, "127.0.0.1") == 0 ||
3260 strcmp(listen_addr, "::1") == 0) {
3261 /* Accept localhost address when GatewayPorts=yes */
Damien Millere84d1032014-05-21 17:13:36 +10003262 addr = listen_addr;
Damien Miller602943d2014-07-04 08:59:41 +10003263 }
3264 } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
3265 strcmp(listen_addr, "::1") == 0) {
3266 /*
3267 * If a specific IPv4/IPv6 localhost address has been
3268 * requested then accept it even if gateway_ports is in
3269 * effect. This allows the client to prefer IPv4 or IPv6.
3270 */
3271 addr = listen_addr;
Damien Millerf6dff7c2011-09-22 21:38:52 +10003272 }
3273 if (wildcardp != NULL)
3274 *wildcardp = wildcard;
3275 return addr;
3276}
3277
Damien Millerb16461c2002-01-22 23:29:22 +11003278static int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003279channel_setup_fwd_listener_tcpip(struct ssh *ssh, int type,
3280 struct Forward *fwd, int *allocated_listen_port,
3281 struct ForwardOptions *fwd_opts)
Damien Miller0bc1bd82000-11-13 22:57:25 +11003282{
Ben Lindstrom99c73b32001-05-05 04:09:47 +00003283 Channel *c;
Damien Miller5e7fd072005-11-05 14:53:39 +11003284 int sock, r, success = 0, wildcard = 0, is_client;
Damien Miller34132e52000-01-14 15:45:46 +11003285 struct addrinfo hints, *ai, *aitop;
Damien Millerf91ee4c2005-03-01 21:24:33 +11003286 const char *host, *addr;
Damien Millerb16461c2002-01-22 23:29:22 +11003287 char ntop[NI_MAXHOST], strport[NI_MAXSERV];
Damien Miller4bf648f2009-02-14 16:28:21 +11003288 in_port_t *lport_p;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10003289
Damien Millerf91ee4c2005-03-01 21:24:33 +11003290 is_client = (type == SSH_CHANNEL_PORT_LISTENER);
Kevin Steves12057502001-02-05 14:54:34 +00003291
millert@openbsd.orgec04dc42015-06-05 15:13:13 +00003292 if (is_client && fwd->connect_path != NULL) {
3293 host = fwd->connect_path;
3294 } else {
3295 host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
3296 fwd->listen_host : fwd->connect_host;
3297 if (host == NULL) {
3298 error("No forward host name.");
3299 return 0;
3300 }
3301 if (strlen(host) >= NI_MAXHOST) {
3302 error("Forward host name too long.");
3303 return 0;
3304 }
Kevin Steves12057502001-02-05 14:54:34 +00003305 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10003306
Damien Millerf6dff7c2011-09-22 21:38:52 +10003307 /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
Damien Miller7acefbb2014-07-18 14:11:24 +10003308 addr = channel_fwd_bind_addr(fwd->listen_host, &wildcard,
3309 is_client, fwd_opts);
3310 debug3("%s: type %d wildcard %d addr %s", __func__,
Damien Millerf91ee4c2005-03-01 21:24:33 +11003311 type, wildcard, (addr == NULL) ? "NULL" : addr);
3312
3313 /*
Damien Miller34132e52000-01-14 15:45:46 +11003314 * getaddrinfo returns a loopback address if the hostname is
3315 * set to NULL and hints.ai_flags is not AI_PASSIVE
Damien Miller5428f641999-11-25 11:54:57 +11003316 */
Damien Miller34132e52000-01-14 15:45:46 +11003317 memset(&hints, 0, sizeof(hints));
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003318 hints.ai_family = ssh->chanctxt->IPv4or6;
Damien Millerf91ee4c2005-03-01 21:24:33 +11003319 hints.ai_flags = wildcard ? AI_PASSIVE : 0;
Damien Miller34132e52000-01-14 15:45:46 +11003320 hints.ai_socktype = SOCK_STREAM;
Damien Miller7acefbb2014-07-18 14:11:24 +10003321 snprintf(strport, sizeof strport, "%d", fwd->listen_port);
Damien Millerf91ee4c2005-03-01 21:24:33 +11003322 if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
3323 if (addr == NULL) {
3324 /* This really shouldn't happen */
3325 packet_disconnect("getaddrinfo: fatal error: %s",
Darren Tucker4abde772007-12-29 02:43:51 +11003326 ssh_gai_strerror(r));
Damien Millerf91ee4c2005-03-01 21:24:33 +11003327 } else {
Damien Miller7acefbb2014-07-18 14:11:24 +10003328 error("%s: getaddrinfo(%.64s): %s", __func__, addr,
Darren Tucker4abde772007-12-29 02:43:51 +11003329 ssh_gai_strerror(r));
Damien Millerf91ee4c2005-03-01 21:24:33 +11003330 }
Damien Millera7270302005-07-06 09:36:05 +10003331 return 0;
Damien Millerf91ee4c2005-03-01 21:24:33 +11003332 }
Damien Miller4bf648f2009-02-14 16:28:21 +11003333 if (allocated_listen_port != NULL)
3334 *allocated_listen_port = 0;
Damien Miller34132e52000-01-14 15:45:46 +11003335 for (ai = aitop; ai; ai = ai->ai_next) {
Damien Miller4bf648f2009-02-14 16:28:21 +11003336 switch (ai->ai_family) {
3337 case AF_INET:
3338 lport_p = &((struct sockaddr_in *)ai->ai_addr)->
3339 sin_port;
3340 break;
3341 case AF_INET6:
3342 lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
3343 sin6_port;
3344 break;
3345 default:
Damien Miller34132e52000-01-14 15:45:46 +11003346 continue;
Damien Miller4bf648f2009-02-14 16:28:21 +11003347 }
3348 /*
3349 * If allocating a port for -R forwards, then use the
3350 * same port for all address families.
3351 */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003352 if (type == SSH_CHANNEL_RPORT_LISTENER &&
3353 fwd->listen_port == 0 && allocated_listen_port != NULL &&
3354 *allocated_listen_port > 0)
Damien Miller4bf648f2009-02-14 16:28:21 +11003355 *lport_p = htons(*allocated_listen_port);
3356
Damien Miller34132e52000-01-14 15:45:46 +11003357 if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003358 strport, sizeof(strport),
3359 NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
Damien Miller7acefbb2014-07-18 14:11:24 +10003360 error("%s: getnameinfo failed", __func__);
Damien Miller34132e52000-01-14 15:45:46 +11003361 continue;
3362 }
3363 /* Create a port to listen for the host. */
Darren Tucker7bd98e72010-01-10 10:31:12 +11003364 sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
Damien Miller34132e52000-01-14 15:45:46 +11003365 if (sock < 0) {
3366 /* this is no error since kernel may not support ipv6 */
3367 verbose("socket: %.100s", strerror(errno));
3368 continue;
3369 }
Damien Miller5e7fd072005-11-05 14:53:39 +11003370
3371 channel_set_reuseaddr(sock);
Damien Miller04ee0f82009-11-18 17:48:30 +11003372 if (ai->ai_family == AF_INET6)
3373 sock_set_v6only(sock);
Damien Millere1383ce2002-09-19 11:49:37 +10003374
Damien Miller4bf648f2009-02-14 16:28:21 +11003375 debug("Local forwarding listening on %s port %s.",
3376 ntop, strport);
Damien Miller95def091999-11-25 00:26:21 +11003377
Damien Miller34132e52000-01-14 15:45:46 +11003378 /* Bind the socket to the address. */
3379 if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003380 /*
3381 * address can be in if use ipv6 address is
3382 * already bound
3383 */
Damien Miller3c7eeb22000-03-03 22:35:33 +11003384 if (!ai->ai_next)
3385 error("bind: %.100s", strerror(errno));
3386 else
3387 verbose("bind: %.100s", strerror(errno));
Kevin Stevesef4eea92001-02-05 12:42:17 +00003388
Damien Miller34132e52000-01-14 15:45:46 +11003389 close(sock);
3390 continue;
3391 }
3392 /* Start listening for connections on the socket. */
Darren Tucker3175eb92003-12-09 19:15:11 +11003393 if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
Damien Miller34132e52000-01-14 15:45:46 +11003394 error("listen: %.100s", strerror(errno));
3395 close(sock);
3396 continue;
3397 }
Damien Miller4bf648f2009-02-14 16:28:21 +11003398
3399 /*
Damien Miller7acefbb2014-07-18 14:11:24 +10003400 * fwd->listen_port == 0 requests a dynamically allocated port -
Damien Miller4bf648f2009-02-14 16:28:21 +11003401 * record what we got.
3402 */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003403 if (type == SSH_CHANNEL_RPORT_LISTENER &&
3404 fwd->listen_port == 0 &&
Damien Miller4bf648f2009-02-14 16:28:21 +11003405 allocated_listen_port != NULL &&
3406 *allocated_listen_port == 0) {
djm@openbsd.org95767262016-03-07 19:02:43 +00003407 *allocated_listen_port = get_local_port(sock);
Damien Miller4bf648f2009-02-14 16:28:21 +11003408 debug("Allocated listen port %d",
3409 *allocated_listen_port);
3410 }
3411
Damien Miller34132e52000-01-14 15:45:46 +11003412 /* Allocate a channel number for the socket. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003413 c = channel_new(ssh, "port listener", type, sock, sock, -1,
Damien Millerbd483e72000-04-30 10:00:53 +10003414 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
Damien Millerb1ca8bb2003-05-14 13:45:42 +10003415 0, "port listener", 1);
Damien Millera1c1b6c2009-01-28 16:29:49 +11003416 c->path = xstrdup(host);
Damien Miller7acefbb2014-07-18 14:11:24 +10003417 c->host_port = fwd->connect_port;
Damien Millerf6dff7c2011-09-22 21:38:52 +10003418 c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
Damien Miller7acefbb2014-07-18 14:11:24 +10003419 if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
Darren Tucker68afb8c2011-10-02 18:59:03 +11003420 !(datafellows & SSH_BUG_DYNAMIC_RPORT))
3421 c->listening_port = *allocated_listen_port;
3422 else
Damien Miller7acefbb2014-07-18 14:11:24 +10003423 c->listening_port = fwd->listen_port;
Damien Miller34132e52000-01-14 15:45:46 +11003424 success = 1;
3425 }
3426 if (success == 0)
Damien Miller7acefbb2014-07-18 14:11:24 +10003427 error("%s: cannot listen to port: %d", __func__,
3428 fwd->listen_port);
Damien Miller34132e52000-01-14 15:45:46 +11003429 freeaddrinfo(aitop);
Kevin Steves12057502001-02-05 14:54:34 +00003430 return success;
Damien Miller95def091999-11-25 00:26:21 +11003431}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10003432
Damien Miller7acefbb2014-07-18 14:11:24 +10003433static int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003434channel_setup_fwd_listener_streamlocal(struct ssh *ssh, int type,
3435 struct Forward *fwd, struct ForwardOptions *fwd_opts)
Damien Miller7acefbb2014-07-18 14:11:24 +10003436{
3437 struct sockaddr_un sunaddr;
3438 const char *path;
3439 Channel *c;
3440 int port, sock;
3441 mode_t omask;
3442
3443 switch (type) {
3444 case SSH_CHANNEL_UNIX_LISTENER:
3445 if (fwd->connect_path != NULL) {
3446 if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
3447 error("Local connecting path too long: %s",
3448 fwd->connect_path);
3449 return 0;
3450 }
3451 path = fwd->connect_path;
3452 port = PORT_STREAMLOCAL;
3453 } else {
3454 if (fwd->connect_host == NULL) {
3455 error("No forward host name.");
3456 return 0;
3457 }
3458 if (strlen(fwd->connect_host) >= NI_MAXHOST) {
3459 error("Forward host name too long.");
3460 return 0;
3461 }
3462 path = fwd->connect_host;
3463 port = fwd->connect_port;
3464 }
3465 break;
3466 case SSH_CHANNEL_RUNIX_LISTENER:
3467 path = fwd->listen_path;
3468 port = PORT_STREAMLOCAL;
3469 break;
3470 default:
3471 error("%s: unexpected channel type %d", __func__, type);
3472 return 0;
3473 }
3474
3475 if (fwd->listen_path == NULL) {
3476 error("No forward path name.");
3477 return 0;
3478 }
3479 if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
3480 error("Local listening path too long: %s", fwd->listen_path);
3481 return 0;
3482 }
3483
3484 debug3("%s: type %d path %s", __func__, type, fwd->listen_path);
3485
3486 /* Start a Unix domain listener. */
3487 omask = umask(fwd_opts->streamlocal_bind_mask);
3488 sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
3489 fwd_opts->streamlocal_bind_unlink);
3490 umask(omask);
3491 if (sock < 0)
3492 return 0;
3493
3494 debug("Local forwarding listening on path %s.", fwd->listen_path);
3495
3496 /* Allocate a channel number for the socket. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003497 c = channel_new(ssh, "unix listener", type, sock, sock, -1,
Damien Miller7acefbb2014-07-18 14:11:24 +10003498 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
3499 0, "unix listener", 1);
3500 c->path = xstrdup(path);
3501 c->host_port = port;
3502 c->listening_port = PORT_STREAMLOCAL;
3503 c->listening_addr = xstrdup(fwd->listen_path);
3504 return 1;
3505}
3506
3507static int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003508channel_cancel_rport_listener_tcpip(struct ssh *ssh,
3509 const char *host, u_short port)
Darren Tuckere7066df2004-05-24 10:18:05 +10003510{
Darren Tuckerc7a6fc42004-08-13 21:18:00 +10003511 u_int i;
3512 int found = 0;
Darren Tuckere7066df2004-05-24 10:18:05 +10003513
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003514 for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3515 Channel *c = ssh->chanctxt->channels[i];
Damien Millerf6dff7c2011-09-22 21:38:52 +10003516 if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
3517 continue;
3518 if (strcmp(c->path, host) == 0 && c->listening_port == port) {
3519 debug2("%s: close channel %d", __func__, i);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003520 channel_free(ssh, c);
Damien Millerf6dff7c2011-09-22 21:38:52 +10003521 found = 1;
3522 }
3523 }
Darren Tuckere7066df2004-05-24 10:18:05 +10003524
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003525 return found;
Damien Millerf6dff7c2011-09-22 21:38:52 +10003526}
3527
Damien Miller7acefbb2014-07-18 14:11:24 +10003528static int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003529channel_cancel_rport_listener_streamlocal(struct ssh *ssh, const char *path)
Damien Millerf6dff7c2011-09-22 21:38:52 +10003530{
3531 u_int i;
3532 int found = 0;
Damien Miller7acefbb2014-07-18 14:11:24 +10003533
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003534 for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3535 Channel *c = ssh->chanctxt->channels[i];
Damien Miller7acefbb2014-07-18 14:11:24 +10003536 if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3537 continue;
3538 if (c->path == NULL)
3539 continue;
3540 if (strcmp(c->path, path) == 0) {
3541 debug2("%s: close channel %d", __func__, i);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003542 channel_free(ssh, c);
Damien Miller7acefbb2014-07-18 14:11:24 +10003543 found = 1;
3544 }
3545 }
3546
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003547 return found;
Damien Miller7acefbb2014-07-18 14:11:24 +10003548}
3549
3550int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003551channel_cancel_rport_listener(struct ssh *ssh, struct Forward *fwd)
Damien Miller7acefbb2014-07-18 14:11:24 +10003552{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003553 if (fwd->listen_path != NULL) {
3554 return channel_cancel_rport_listener_streamlocal(ssh,
3555 fwd->listen_path);
3556 } else {
3557 return channel_cancel_rport_listener_tcpip(ssh,
3558 fwd->listen_host, fwd->listen_port);
3559 }
Damien Miller7acefbb2014-07-18 14:11:24 +10003560}
3561
3562static int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003563channel_cancel_lport_listener_tcpip(struct ssh *ssh,
3564 const char *lhost, u_short lport, int cport,
3565 struct ForwardOptions *fwd_opts)
Damien Miller7acefbb2014-07-18 14:11:24 +10003566{
3567 u_int i;
3568 int found = 0;
3569 const char *addr = channel_fwd_bind_addr(lhost, NULL, 1, fwd_opts);
Damien Millerf6dff7c2011-09-22 21:38:52 +10003570
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003571 for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3572 Channel *c = ssh->chanctxt->channels[i];
Damien Millerf6dff7c2011-09-22 21:38:52 +10003573 if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
3574 continue;
Damien Millerff773642011-09-22 21:39:48 +10003575 if (c->listening_port != lport)
Damien Millerf6dff7c2011-09-22 21:38:52 +10003576 continue;
Damien Millerff773642011-09-22 21:39:48 +10003577 if (cport == CHANNEL_CANCEL_PORT_STATIC) {
3578 /* skip dynamic forwardings */
3579 if (c->host_port == 0)
3580 continue;
3581 } else {
3582 if (c->host_port != cport)
3583 continue;
3584 }
Damien Millerf6dff7c2011-09-22 21:38:52 +10003585 if ((c->listening_addr == NULL && addr != NULL) ||
3586 (c->listening_addr != NULL && addr == NULL))
3587 continue;
3588 if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
Darren Tuckere6ed8392004-08-29 16:29:44 +10003589 debug2("%s: close channel %d", __func__, i);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003590 channel_free(ssh, c);
Darren Tuckere7066df2004-05-24 10:18:05 +10003591 found = 1;
3592 }
3593 }
3594
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003595 return found;
Darren Tuckere7066df2004-05-24 10:18:05 +10003596}
3597
Damien Miller7acefbb2014-07-18 14:11:24 +10003598static int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003599channel_cancel_lport_listener_streamlocal(struct ssh *ssh, const char *path)
Damien Miller7acefbb2014-07-18 14:11:24 +10003600{
3601 u_int i;
3602 int found = 0;
3603
3604 if (path == NULL) {
3605 error("%s: no path specified.", __func__);
3606 return 0;
3607 }
3608
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003609 for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3610 Channel *c = ssh->chanctxt->channels[i];
Damien Miller7acefbb2014-07-18 14:11:24 +10003611 if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
3612 continue;
3613 if (c->listening_addr == NULL)
3614 continue;
3615 if (strcmp(c->listening_addr, path) == 0) {
3616 debug2("%s: close channel %d", __func__, i);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003617 channel_free(ssh, c);
Damien Miller7acefbb2014-07-18 14:11:24 +10003618 found = 1;
3619 }
3620 }
3621
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003622 return found;
Damien Miller7acefbb2014-07-18 14:11:24 +10003623}
3624
3625int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003626channel_cancel_lport_listener(struct ssh *ssh,
3627 struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
Damien Miller7acefbb2014-07-18 14:11:24 +10003628{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003629 if (fwd->listen_path != NULL) {
3630 return channel_cancel_lport_listener_streamlocal(ssh,
3631 fwd->listen_path);
3632 } else {
3633 return channel_cancel_lport_listener_tcpip(ssh,
3634 fwd->listen_host, fwd->listen_port, cport, fwd_opts);
3635 }
Damien Miller7acefbb2014-07-18 14:11:24 +10003636}
3637
markus@openbsd.orgc2212192017-05-30 08:49:58 +00003638/* protocol local port fwd, used by ssh */
Damien Millerb16461c2002-01-22 23:29:22 +11003639int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003640channel_setup_local_fwd_listener(struct ssh *ssh,
3641 struct Forward *fwd, struct ForwardOptions *fwd_opts)
Damien Millerb16461c2002-01-22 23:29:22 +11003642{
Damien Miller7acefbb2014-07-18 14:11:24 +10003643 if (fwd->listen_path != NULL) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003644 return channel_setup_fwd_listener_streamlocal(ssh,
Damien Miller7acefbb2014-07-18 14:11:24 +10003645 SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
3646 } else {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003647 return channel_setup_fwd_listener_tcpip(ssh,
3648 SSH_CHANNEL_PORT_LISTENER, fwd, NULL, fwd_opts);
Damien Miller7acefbb2014-07-18 14:11:24 +10003649 }
Damien Millerb16461c2002-01-22 23:29:22 +11003650}
3651
3652/* protocol v2 remote port fwd, used by sshd */
3653int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003654channel_setup_remote_fwd_listener(struct ssh *ssh, struct Forward *fwd,
Damien Miller7acefbb2014-07-18 14:11:24 +10003655 int *allocated_listen_port, struct ForwardOptions *fwd_opts)
Damien Millerb16461c2002-01-22 23:29:22 +11003656{
Damien Miller7acefbb2014-07-18 14:11:24 +10003657 if (fwd->listen_path != NULL) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003658 return channel_setup_fwd_listener_streamlocal(ssh,
Damien Miller7acefbb2014-07-18 14:11:24 +10003659 SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
3660 } else {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003661 return channel_setup_fwd_listener_tcpip(ssh,
Damien Miller7acefbb2014-07-18 14:11:24 +10003662 SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
3663 fwd_opts);
3664 }
Damien Millerb16461c2002-01-22 23:29:22 +11003665}
3666
Damien Miller5428f641999-11-25 11:54:57 +11003667/*
Damien Millerf6dff7c2011-09-22 21:38:52 +10003668 * Translate the requested rfwd listen host to something usable for
3669 * this server.
3670 */
3671static const char *
3672channel_rfwd_bind_host(const char *listen_host)
3673{
3674 if (listen_host == NULL) {
3675 if (datafellows & SSH_BUG_RFWD_ADDR)
3676 return "127.0.0.1";
3677 else
3678 return "localhost";
3679 } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
3680 if (datafellows & SSH_BUG_RFWD_ADDR)
3681 return "0.0.0.0";
3682 else
3683 return "";
3684 } else
3685 return listen_host;
3686}
3687
3688/*
Damien Miller5428f641999-11-25 11:54:57 +11003689 * Initiate forwarding of connections to port "port" on remote host through
3690 * the secure channel to host:port from local side.
Darren Tucker68afb8c2011-10-02 18:59:03 +11003691 * Returns handle (index) for updating the dynamic listen port with
3692 * channel_update_permitted_opens().
Damien Miller5428f641999-11-25 11:54:57 +11003693 */
Darren Tuckere7d4b192006-07-12 22:17:10 +10003694int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003695channel_request_remote_forwarding(struct ssh *ssh, struct Forward *fwd)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10003696{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003697 int r, success = 0, idx = -1;
3698 char *host_to_connect, *listen_host, *listen_path;
3699 int port_to_connect, listen_port;
Damien Miller0bc1bd82000-11-13 22:57:25 +11003700
Damien Miller95def091999-11-25 00:26:21 +11003701 /* Send the forward request to the remote side. */
djm@openbsd.org97f4d302017-04-30 23:13:25 +00003702 if (fwd->listen_path != NULL) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003703 if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3704 (r = sshpkt_put_cstring(ssh,
3705 "streamlocal-forward@openssh.com")) != 0 ||
3706 (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3707 (r = sshpkt_put_cstring(ssh, fwd->listen_path)) != 0 ||
3708 (r = sshpkt_send(ssh)) != 0 ||
3709 (r = ssh_packet_write_wait(ssh)) != 0)
3710 fatal("%s: request streamlocal: %s",
3711 __func__, ssh_err(r));
Damien Miller7acefbb2014-07-18 14:11:24 +10003712 } else {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003713 if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3714 (r = sshpkt_put_cstring(ssh, "tcpip-forward")) != 0 ||
3715 (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3716 (r = sshpkt_put_cstring(ssh,
3717 channel_rfwd_bind_host(fwd->listen_host))) != 0 ||
3718 (r = sshpkt_put_u32(ssh, fwd->listen_port)) != 0 ||
3719 (r = sshpkt_send(ssh)) != 0 ||
3720 (r = ssh_packet_write_wait(ssh)) != 0)
3721 fatal("%s: request tcpip-forward: %s",
3722 __func__, ssh_err(r));
Damien Miller0bc1bd82000-11-13 22:57:25 +11003723 }
djm@openbsd.org97f4d302017-04-30 23:13:25 +00003724 /* Assume that server accepts the request */
3725 success = 1;
Damien Miller0bc1bd82000-11-13 22:57:25 +11003726 if (success) {
Damien Miller232cfb12010-06-26 09:50:30 +10003727 /* Record that connection to this host/port is permitted. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003728 host_to_connect = listen_host = listen_path = NULL;
3729 port_to_connect = listen_port = 0;
Damien Miller7acefbb2014-07-18 14:11:24 +10003730 if (fwd->connect_path != NULL) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003731 host_to_connect = xstrdup(fwd->connect_path);
3732 port_to_connect = PORT_STREAMLOCAL;
Damien Miller7acefbb2014-07-18 14:11:24 +10003733 } else {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003734 host_to_connect = xstrdup(fwd->connect_host);
3735 port_to_connect = fwd->connect_port;
Damien Miller7acefbb2014-07-18 14:11:24 +10003736 }
3737 if (fwd->listen_path != NULL) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003738 listen_path = xstrdup(fwd->listen_path);
3739 listen_port = PORT_STREAMLOCAL;
Damien Miller7acefbb2014-07-18 14:11:24 +10003740 } else {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003741 if (fwd->listen_host != NULL)
3742 listen_host = xstrdup(fwd->listen_host);
3743 listen_port = fwd->listen_port;
Damien Miller7acefbb2014-07-18 14:11:24 +10003744 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003745 idx = fwd_perm_list_add(ssh, FWDPERM_USER,
3746 host_to_connect, port_to_connect,
3747 listen_host, listen_path, listen_port, NULL);
Damien Miller33b13562000-04-04 14:38:59 +10003748 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003749 return idx;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10003750}
3751
Damien Miller4b3ed642014-07-02 15:29:40 +10003752static int
3753open_match(ForwardPermission *allowed_open, const char *requestedhost,
Damien Miller7acefbb2014-07-18 14:11:24 +10003754 int requestedport)
Damien Miller4b3ed642014-07-02 15:29:40 +10003755{
3756 if (allowed_open->host_to_connect == NULL)
3757 return 0;
3758 if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
3759 allowed_open->port_to_connect != requestedport)
3760 return 0;
dtucker@openbsd.orgd7eabc82016-07-19 11:38:53 +00003761 if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 &&
3762 strcmp(allowed_open->host_to_connect, requestedhost) != 0)
Damien Miller4b3ed642014-07-02 15:29:40 +10003763 return 0;
3764 return 1;
3765}
3766
3767/*
Damien Miller7acefbb2014-07-18 14:11:24 +10003768 * Note that in the listen host/port case
Damien Miller4b3ed642014-07-02 15:29:40 +10003769 * we don't support FWD_PERMIT_ANY_PORT and
3770 * need to translate between the configured-host (listen_host)
3771 * and what we've sent to the remote server (channel_rfwd_bind_host)
3772 */
3773static int
Damien Miller7acefbb2014-07-18 14:11:24 +10003774open_listen_match_tcpip(ForwardPermission *allowed_open,
3775 const char *requestedhost, u_short requestedport, int translate)
Damien Miller4b3ed642014-07-02 15:29:40 +10003776{
3777 const char *allowed_host;
3778
3779 if (allowed_open->host_to_connect == NULL)
3780 return 0;
3781 if (allowed_open->listen_port != requestedport)
3782 return 0;
Damien Miller3a48cc02014-07-06 09:32:49 +10003783 if (!translate && allowed_open->listen_host == NULL &&
3784 requestedhost == NULL)
3785 return 1;
Damien Miller4b3ed642014-07-02 15:29:40 +10003786 allowed_host = translate ?
3787 channel_rfwd_bind_host(allowed_open->listen_host) :
3788 allowed_open->listen_host;
3789 if (allowed_host == NULL ||
3790 strcmp(allowed_host, requestedhost) != 0)
3791 return 0;
3792 return 1;
3793}
3794
Damien Miller7acefbb2014-07-18 14:11:24 +10003795static int
3796open_listen_match_streamlocal(ForwardPermission *allowed_open,
3797 const char *requestedpath)
3798{
3799 if (allowed_open->host_to_connect == NULL)
3800 return 0;
3801 if (allowed_open->listen_port != PORT_STREAMLOCAL)
3802 return 0;
3803 if (allowed_open->listen_path == NULL ||
3804 strcmp(allowed_open->listen_path, requestedpath) != 0)
3805 return 0;
3806 return 1;
3807}
3808
Damien Miller5428f641999-11-25 11:54:57 +11003809/*
Darren Tuckerfc959702004-07-17 16:12:08 +10003810 * Request cancellation of remote forwarding of connection host:port from
Darren Tuckere7066df2004-05-24 10:18:05 +10003811 * local side.
3812 */
Damien Miller7acefbb2014-07-18 14:11:24 +10003813static int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003814channel_request_rforward_cancel_tcpip(struct ssh *ssh,
3815 const char *host, u_short port)
Darren Tuckere7066df2004-05-24 10:18:05 +10003816{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003817 struct ssh_channels *sc = ssh->chanctxt;
3818 int r;
3819 u_int i;
3820 ForwardPermission *fp;
Darren Tuckere7066df2004-05-24 10:18:05 +10003821
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003822 for (i = 0; i < sc->num_permitted_opens; i++) {
3823 fp = &sc->permitted_opens[i];
3824 if (open_listen_match_tcpip(fp, host, port, 0))
Darren Tuckere7066df2004-05-24 10:18:05 +10003825 break;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003826 fp = NULL;
Darren Tuckere7066df2004-05-24 10:18:05 +10003827 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003828 if (fp == NULL) {
Darren Tuckere7066df2004-05-24 10:18:05 +10003829 debug("%s: requested forward not found", __func__);
Damien Millerf6dff7c2011-09-22 21:38:52 +10003830 return -1;
Darren Tuckere7066df2004-05-24 10:18:05 +10003831 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003832 if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3833 (r = sshpkt_put_cstring(ssh, "cancel-tcpip-forward")) != 0 ||
3834 (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
3835 (r = sshpkt_put_cstring(ssh, channel_rfwd_bind_host(host))) != 0 ||
3836 (r = sshpkt_put_u32(ssh, port)) != 0 ||
3837 (r = sshpkt_send(ssh)) != 0)
3838 fatal("%s: send cancel: %s", __func__, ssh_err(r));
Darren Tuckere7066df2004-05-24 10:18:05 +10003839
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003840 fwd_perm_clear(fp); /* unregister */
Damien Millerf6dff7c2011-09-22 21:38:52 +10003841
3842 return 0;
Darren Tuckere7066df2004-05-24 10:18:05 +10003843}
3844
3845/*
Damien Miller7acefbb2014-07-18 14:11:24 +10003846 * Request cancellation of remote forwarding of Unix domain socket
3847 * path from local side.
3848 */
3849static int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003850channel_request_rforward_cancel_streamlocal(struct ssh *ssh, const char *path)
Damien Miller7acefbb2014-07-18 14:11:24 +10003851{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003852 struct ssh_channels *sc = ssh->chanctxt;
3853 int r;
3854 u_int i;
3855 ForwardPermission *fp;
Damien Miller7acefbb2014-07-18 14:11:24 +10003856
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003857 for (i = 0; i < sc->num_permitted_opens; i++) {
3858 fp = &sc->permitted_opens[i];
3859 if (open_listen_match_streamlocal(fp, path))
Damien Miller7acefbb2014-07-18 14:11:24 +10003860 break;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003861 fp = NULL;
Damien Miller7acefbb2014-07-18 14:11:24 +10003862 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003863 if (fp == NULL) {
Damien Miller7acefbb2014-07-18 14:11:24 +10003864 debug("%s: requested forward not found", __func__);
3865 return -1;
3866 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003867 if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3868 (r = sshpkt_put_cstring(ssh,
3869 "cancel-streamlocal-forward@openssh.com")) != 0 ||
3870 (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
3871 (r = sshpkt_put_cstring(ssh, path)) != 0 ||
3872 (r = sshpkt_send(ssh)) != 0)
3873 fatal("%s: send cancel: %s", __func__, ssh_err(r));
Damien Miller7acefbb2014-07-18 14:11:24 +10003874
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003875 fwd_perm_clear(fp); /* unregister */
Damien Miller7acefbb2014-07-18 14:11:24 +10003876
3877 return 0;
3878}
3879
3880/*
3881 * Request cancellation of remote forwarding of a connection from local side.
3882 */
3883int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003884channel_request_rforward_cancel(struct ssh *ssh, struct Forward *fwd)
Damien Miller7acefbb2014-07-18 14:11:24 +10003885{
3886 if (fwd->listen_path != NULL) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003887 return channel_request_rforward_cancel_streamlocal(ssh,
3888 fwd->listen_path);
Damien Miller7acefbb2014-07-18 14:11:24 +10003889 } else {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003890 return channel_request_rforward_cancel_tcpip(ssh,
3891 fwd->listen_host,
3892 fwd->listen_port ? fwd->listen_port : fwd->allocated_port);
Damien Miller7acefbb2014-07-18 14:11:24 +10003893 }
3894}
3895
3896/*
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00003897 * Permits opening to any host/port if permitted_opens[] is empty. This is
3898 * usually called by the server, because the user could connect to any port
3899 * anyway, and the server has no way to know but to trust the client anyway.
3900 */
3901void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003902channel_permit_all_opens(struct ssh *ssh)
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00003903{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003904 if (ssh->chanctxt->num_permitted_opens == 0)
3905 ssh->chanctxt->all_opens_permitted = 1;
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00003906}
3907
Ben Lindstroma3700052001-04-05 23:26:32 +00003908void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003909channel_add_permitted_opens(struct ssh *ssh, char *host, int port)
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00003910{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003911 struct ssh_channels *sc = ssh->chanctxt;
3912
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00003913 debug("allow port forwarding to host %s port %d", host, port);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003914 fwd_perm_list_add(ssh, FWDPERM_USER, host, port, NULL, NULL, 0, NULL);
3915 sc->all_opens_permitted = 0;
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00003916}
3917
Darren Tucker68afb8c2011-10-02 18:59:03 +11003918/*
3919 * Update the listen port for a dynamic remote forward, after
3920 * the actual 'newport' has been allocated. If 'newport' < 0 is
3921 * passed then they entry will be invalidated.
3922 */
3923void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003924channel_update_permitted_opens(struct ssh *ssh, int idx, int newport)
Darren Tucker68afb8c2011-10-02 18:59:03 +11003925{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003926 struct ssh_channels *sc = ssh->chanctxt;
3927
3928 if (idx < 0 || (u_int)idx >= sc->num_permitted_opens) {
3929 debug("%s: index out of range: %d num_permitted_opens %d",
3930 __func__, idx, sc->num_permitted_opens);
Darren Tucker68afb8c2011-10-02 18:59:03 +11003931 return;
3932 }
3933 debug("%s allowed port %d for forwarding to host %s port %d",
3934 newport > 0 ? "Updating" : "Removing",
3935 newport,
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003936 sc->permitted_opens[idx].host_to_connect,
3937 sc->permitted_opens[idx].port_to_connect);
3938 if (newport <= 0)
3939 fwd_perm_clear(&sc->permitted_opens[idx]);
3940 else {
3941 sc->permitted_opens[idx].listen_port =
Darren Tucker68afb8c2011-10-02 18:59:03 +11003942 (datafellows & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
Darren Tucker68afb8c2011-10-02 18:59:03 +11003943 }
3944}
3945
Damien Millera765cf42006-07-24 14:08:13 +10003946int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003947channel_add_adm_permitted_opens(struct ssh *ssh, char *host, int port)
Damien Miller9b439df2006-07-24 14:04:00 +10003948{
Damien Millera765cf42006-07-24 14:08:13 +10003949 debug("config allows port forwarding to host %s port %d", host, port);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003950 return fwd_perm_list_add(ssh, FWDPERM_ADMIN, host, port,
3951 NULL, NULL, 0, NULL);
Damien Miller9b439df2006-07-24 14:04:00 +10003952}
3953
3954void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003955channel_disable_adm_local_opens(struct ssh *ssh)
Damien Millerc6081482012-04-22 11:18:53 +10003956{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003957 channel_clear_adm_permitted_opens(ssh);
3958 fwd_perm_list_add(ssh, FWDPERM_ADMIN, NULL, 0, NULL, NULL, 0, NULL);
Damien Millerc6081482012-04-22 11:18:53 +10003959}
3960
3961void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003962channel_clear_permitted_opens(struct ssh *ssh)
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00003963{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003964 struct ssh_channels *sc = ssh->chanctxt;
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00003965
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003966 sc->permitted_opens = xrecallocarray(sc->permitted_opens,
3967 sc->num_permitted_opens, 0, sizeof(*sc->permitted_opens));
3968 sc->num_permitted_opens = 0;
Damien Miller9b439df2006-07-24 14:04:00 +10003969}
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00003970
Damien Miller9b439df2006-07-24 14:04:00 +10003971void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003972channel_clear_adm_permitted_opens(struct ssh *ssh)
Damien Miller9b439df2006-07-24 14:04:00 +10003973{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003974 struct ssh_channels *sc = ssh->chanctxt;
Damien Miller9b439df2006-07-24 14:04:00 +10003975
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00003976 sc->permitted_adm_opens = xrecallocarray(sc->permitted_adm_opens,
3977 sc->num_adm_permitted_opens, 0, sizeof(*sc->permitted_adm_opens));
3978 sc->num_adm_permitted_opens = 0;
Darren Tuckere7140f22008-06-10 23:01:51 +10003979}
3980
Darren Tucker1338b9e2011-10-02 18:57:35 +11003981/* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
3982int
3983permitopen_port(const char *p)
3984{
3985 int port;
3986
3987 if (strcmp(p, "*") == 0)
3988 return FWD_PERMIT_ANY_PORT;
3989 if ((port = a2port(p)) > 0)
3990 return port;
3991 return -1;
3992}
3993
Damien Millerbd740252008-05-19 15:37:09 +10003994/* Try to start non-blocking connect to next host in cctx list */
Ben Lindstrombba81212001-06-25 05:01:22 +00003995static int
Damien Millerbd740252008-05-19 15:37:09 +10003996connect_next(struct channel_connect *cctx)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10003997{
Damien Millerbd740252008-05-19 15:37:09 +10003998 int sock, saved_errno;
Damien Miller7acefbb2014-07-18 14:11:24 +10003999 struct sockaddr_un *sunaddr;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004000 char ntop[NI_MAXHOST];
4001 char strport[MAXIMUM(NI_MAXSERV, sizeof(sunaddr->sun_path))];
Damien Miller95def091999-11-25 00:26:21 +11004002
Damien Millerbd740252008-05-19 15:37:09 +10004003 for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
Damien Miller7acefbb2014-07-18 14:11:24 +10004004 switch (cctx->ai->ai_family) {
4005 case AF_UNIX:
4006 /* unix:pathname instead of host:port */
4007 sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
4008 strlcpy(ntop, "unix", sizeof(ntop));
4009 strlcpy(strport, sunaddr->sun_path, sizeof(strport));
4010 break;
4011 case AF_INET:
4012 case AF_INET6:
4013 if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
4014 ntop, sizeof(ntop), strport, sizeof(strport),
4015 NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
4016 error("connect_next: getnameinfo failed");
4017 continue;
4018 }
4019 break;
4020 default:
Damien Miller34132e52000-01-14 15:45:46 +11004021 continue;
4022 }
Darren Tucker7bd98e72010-01-10 10:31:12 +11004023 if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
4024 cctx->ai->ai_protocol)) == -1) {
Damien Millerbd740252008-05-19 15:37:09 +10004025 if (cctx->ai->ai_next == NULL)
Damien Millerb46b9f32003-01-10 21:45:12 +11004026 error("socket: %.100s", strerror(errno));
4027 else
4028 verbose("socket: %.100s", strerror(errno));
Damien Miller34132e52000-01-14 15:45:46 +11004029 continue;
4030 }
Damien Miller232711f2004-06-15 10:35:30 +10004031 if (set_nonblock(sock) == -1)
4032 fatal("%s: set_nonblock(%d)", __func__, sock);
Damien Millerbd740252008-05-19 15:37:09 +10004033 if (connect(sock, cctx->ai->ai_addr,
4034 cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
4035 debug("connect_next: host %.100s ([%.100s]:%s): "
4036 "%.100s", cctx->host, ntop, strport,
Damien Miller34132e52000-01-14 15:45:46 +11004037 strerror(errno));
Damien Millerbd740252008-05-19 15:37:09 +10004038 saved_errno = errno;
Damien Miller34132e52000-01-14 15:45:46 +11004039 close(sock);
Damien Millerbd740252008-05-19 15:37:09 +10004040 errno = saved_errno;
Kevin Stevesef4eea92001-02-05 12:42:17 +00004041 continue; /* fail -- try next */
Damien Miller34132e52000-01-14 15:45:46 +11004042 }
Damien Miller7acefbb2014-07-18 14:11:24 +10004043 if (cctx->ai->ai_family != AF_UNIX)
4044 set_nodelay(sock);
Damien Millerbd740252008-05-19 15:37:09 +10004045 debug("connect_next: host %.100s ([%.100s]:%s) "
4046 "in progress, fd=%d", cctx->host, ntop, strport, sock);
4047 cctx->ai = cctx->ai->ai_next;
Damien Millerbd740252008-05-19 15:37:09 +10004048 return sock;
Damien Miller34132e52000-01-14 15:45:46 +11004049 }
Damien Miller0bc1bd82000-11-13 22:57:25 +11004050 return -1;
4051}
Damien Millerb38eff82000-04-01 11:09:21 +10004052
Damien Millerbd740252008-05-19 15:37:09 +10004053static void
4054channel_connect_ctx_free(struct channel_connect *cctx)
4055{
Darren Tuckera627d422013-06-02 07:31:17 +10004056 free(cctx->host);
Damien Miller7acefbb2014-07-18 14:11:24 +10004057 if (cctx->aitop) {
4058 if (cctx->aitop->ai_family == AF_UNIX)
4059 free(cctx->aitop);
4060 else
4061 freeaddrinfo(cctx->aitop);
4062 }
Damien Miller1d2c4562014-02-04 11:18:20 +11004063 memset(cctx, 0, sizeof(*cctx));
Damien Millerbd740252008-05-19 15:37:09 +10004064}
4065
dtucker@openbsd.org858252f2017-02-01 02:59:09 +00004066/*
markus@openbsd.org609d7a62017-09-21 19:16:53 +00004067 * Return connecting socket to remote host:port or local socket path,
dtucker@openbsd.org858252f2017-02-01 02:59:09 +00004068 * passing back the failure reason if appropriate.
4069 */
markus@openbsd.org609d7a62017-09-21 19:16:53 +00004070static int
4071connect_to_helper(struct ssh *ssh, const char *name, int port, int socktype,
4072 char *ctype, char *rname, struct channel_connect *cctx,
4073 int *reason, const char **errmsg)
Damien Millerbd740252008-05-19 15:37:09 +10004074{
4075 struct addrinfo hints;
4076 int gaierr;
4077 int sock = -1;
4078 char strport[NI_MAXSERV];
Damien Miller7acefbb2014-07-18 14:11:24 +10004079
4080 if (port == PORT_STREAMLOCAL) {
4081 struct sockaddr_un *sunaddr;
4082 struct addrinfo *ai;
4083
4084 if (strlen(name) > sizeof(sunaddr->sun_path)) {
4085 error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
markus@openbsd.org609d7a62017-09-21 19:16:53 +00004086 return -1;
Damien Miller7acefbb2014-07-18 14:11:24 +10004087 }
4088
4089 /*
4090 * Fake up a struct addrinfo for AF_UNIX connections.
4091 * channel_connect_ctx_free() must check ai_family
4092 * and use free() not freeaddirinfo() for AF_UNIX.
4093 */
4094 ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
4095 memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
4096 ai->ai_addr = (struct sockaddr *)(ai + 1);
4097 ai->ai_addrlen = sizeof(*sunaddr);
4098 ai->ai_family = AF_UNIX;
markus@openbsd.org609d7a62017-09-21 19:16:53 +00004099 ai->ai_socktype = socktype;
Damien Miller7acefbb2014-07-18 14:11:24 +10004100 ai->ai_protocol = PF_UNSPEC;
4101 sunaddr = (struct sockaddr_un *)ai->ai_addr;
4102 sunaddr->sun_family = AF_UNIX;
4103 strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
markus@openbsd.org609d7a62017-09-21 19:16:53 +00004104 cctx->aitop = ai;
Damien Miller7acefbb2014-07-18 14:11:24 +10004105 } else {
4106 memset(&hints, 0, sizeof(hints));
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004107 hints.ai_family = ssh->chanctxt->IPv4or6;
markus@openbsd.org609d7a62017-09-21 19:16:53 +00004108 hints.ai_socktype = socktype;
Damien Miller7acefbb2014-07-18 14:11:24 +10004109 snprintf(strport, sizeof strport, "%d", port);
markus@openbsd.org609d7a62017-09-21 19:16:53 +00004110 if ((gaierr = getaddrinfo(name, strport, &hints, &cctx->aitop))
dtucker@openbsd.org858252f2017-02-01 02:59:09 +00004111 != 0) {
4112 if (errmsg != NULL)
4113 *errmsg = ssh_gai_strerror(gaierr);
4114 if (reason != NULL)
4115 *reason = SSH2_OPEN_CONNECT_FAILED;
Damien Miller7acefbb2014-07-18 14:11:24 +10004116 error("connect_to %.100s: unknown host (%s)", name,
4117 ssh_gai_strerror(gaierr));
markus@openbsd.org609d7a62017-09-21 19:16:53 +00004118 return -1;
Damien Miller7acefbb2014-07-18 14:11:24 +10004119 }
Damien Millerbd740252008-05-19 15:37:09 +10004120 }
4121
markus@openbsd.org609d7a62017-09-21 19:16:53 +00004122 cctx->host = xstrdup(name);
4123 cctx->port = port;
4124 cctx->ai = cctx->aitop;
Damien Millerbd740252008-05-19 15:37:09 +10004125
markus@openbsd.org609d7a62017-09-21 19:16:53 +00004126 if ((sock = connect_next(cctx)) == -1) {
Damien Millerbd740252008-05-19 15:37:09 +10004127 error("connect to %.100s port %d failed: %s",
Damien Miller7acefbb2014-07-18 14:11:24 +10004128 name, port, strerror(errno));
markus@openbsd.org609d7a62017-09-21 19:16:53 +00004129 return -1;
4130 }
4131
4132 return sock;
4133}
4134
4135/* Return CONNECTING channel to remote host:port or local socket path */
4136static Channel *
4137connect_to(struct ssh *ssh, const char *host, int port,
4138 char *ctype, char *rname)
4139{
4140 struct channel_connect cctx;
4141 Channel *c;
4142 int sock;
4143
4144 memset(&cctx, 0, sizeof(cctx));
4145 sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4146 &cctx, NULL, NULL);
4147 if (sock == -1) {
Damien Millerbd740252008-05-19 15:37:09 +10004148 channel_connect_ctx_free(&cctx);
4149 return NULL;
4150 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004151 c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
Damien Millerbd740252008-05-19 15:37:09 +10004152 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
markus@openbsd.org609d7a62017-09-21 19:16:53 +00004153 c->host_port = port;
4154 c->path = xstrdup(host);
Damien Millerbd740252008-05-19 15:37:09 +10004155 c->connect_ctx = cctx;
Damien Millerbd740252008-05-19 15:37:09 +10004156
markus@openbsd.org609d7a62017-09-21 19:16:53 +00004157 return c;
dtucker@openbsd.org858252f2017-02-01 02:59:09 +00004158}
4159
markus@openbsd.org8d057842016-09-30 09:19:13 +00004160/*
4161 * returns either the newly connected channel or the downstream channel
4162 * that needs to deal with this connection.
4163 */
Damien Millerbd740252008-05-19 15:37:09 +10004164Channel *
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004165channel_connect_by_listen_address(struct ssh *ssh, const char *listen_host,
Damien Miller4b3ed642014-07-02 15:29:40 +10004166 u_short listen_port, char *ctype, char *rname)
Damien Millerbd740252008-05-19 15:37:09 +10004167{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004168 struct ssh_channels *sc = ssh->chanctxt;
4169 u_int i;
4170 ForwardPermission *fp;
Damien Millerbd740252008-05-19 15:37:09 +10004171
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004172 for (i = 0; i < sc->num_permitted_opens; i++) {
4173 fp = &sc->permitted_opens[i];
4174 if (open_listen_match_tcpip(fp, listen_host, listen_port, 1)) {
4175 if (fp->downstream)
4176 return fp->downstream;
markus@openbsd.org609d7a62017-09-21 19:16:53 +00004177 if (fp->port_to_connect == 0)
4178 return rdynamic_connect_prepare(ssh,
4179 ctype, rname);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004180 return connect_to(ssh,
4181 fp->host_to_connect, fp->port_to_connect,
4182 ctype, rname);
Damien Millerbd740252008-05-19 15:37:09 +10004183 }
4184 }
4185 error("WARNING: Server requests forwarding for unknown listen_port %d",
4186 listen_port);
4187 return NULL;
4188}
4189
Damien Miller7acefbb2014-07-18 14:11:24 +10004190Channel *
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004191channel_connect_by_listen_path(struct ssh *ssh, const char *path,
4192 char *ctype, char *rname)
Damien Miller7acefbb2014-07-18 14:11:24 +10004193{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004194 struct ssh_channels *sc = ssh->chanctxt;
4195 u_int i;
4196 ForwardPermission *fp;
Damien Miller7acefbb2014-07-18 14:11:24 +10004197
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004198 for (i = 0; i < sc->num_permitted_opens; i++) {
4199 fp = &sc->permitted_opens[i];
4200 if (open_listen_match_streamlocal(fp, path)) {
4201 return connect_to(ssh,
4202 fp->host_to_connect, fp->port_to_connect,
4203 ctype, rname);
Damien Miller7acefbb2014-07-18 14:11:24 +10004204 }
4205 }
4206 error("WARNING: Server requests forwarding for unknown path %.100s",
4207 path);
4208 return NULL;
4209}
4210
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00004211/* Check if connecting to that port is permitted and connect. */
Damien Millerbd740252008-05-19 15:37:09 +10004212Channel *
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004213channel_connect_to_port(struct ssh *ssh, const char *host, u_short port,
4214 char *ctype, char *rname, int *reason, const char **errmsg)
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00004215{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004216 struct ssh_channels *sc = ssh->chanctxt;
markus@openbsd.org609d7a62017-09-21 19:16:53 +00004217 struct channel_connect cctx;
4218 Channel *c;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004219 u_int i, permit, permit_adm = 1;
markus@openbsd.org609d7a62017-09-21 19:16:53 +00004220 int sock;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004221 ForwardPermission *fp;
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00004222
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004223 permit = sc->all_opens_permitted;
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00004224 if (!permit) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004225 for (i = 0; i < sc->num_permitted_opens; i++) {
4226 fp = &sc->permitted_opens[i];
4227 if (open_match(fp, host, port)) {
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00004228 permit = 1;
Damien Miller4b3ed642014-07-02 15:29:40 +10004229 break;
4230 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004231 }
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00004232 }
Damien Miller9b439df2006-07-24 14:04:00 +10004233
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004234 if (sc->num_adm_permitted_opens > 0) {
Damien Miller9b439df2006-07-24 14:04:00 +10004235 permit_adm = 0;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004236 for (i = 0; i < sc->num_adm_permitted_opens; i++) {
4237 fp = &sc->permitted_adm_opens[i];
4238 if (open_match(fp, host, port)) {
Damien Miller9b439df2006-07-24 14:04:00 +10004239 permit_adm = 1;
Damien Miller4b3ed642014-07-02 15:29:40 +10004240 break;
4241 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004242 }
Damien Miller9b439df2006-07-24 14:04:00 +10004243 }
4244
4245 if (!permit || !permit_adm) {
Damien Miller996acd22003-04-09 20:59:48 +10004246 logit("Received request to connect to host %.100s port %d, "
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00004247 "but the request was denied.", host, port);
dtucker@openbsd.org858252f2017-02-01 02:59:09 +00004248 if (reason != NULL)
4249 *reason = SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED;
Damien Millerbd740252008-05-19 15:37:09 +10004250 return NULL;
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00004251 }
markus@openbsd.org609d7a62017-09-21 19:16:53 +00004252
4253 memset(&cctx, 0, sizeof(cctx));
4254 sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4255 &cctx, reason, errmsg);
4256 if (sock == -1) {
4257 channel_connect_ctx_free(&cctx);
4258 return NULL;
4259 }
4260
4261 c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
4262 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4263 c->host_port = port;
4264 c->path = xstrdup(host);
4265 c->connect_ctx = cctx;
4266
4267 return c;
Ben Lindstrom7bb8b492001-03-17 00:47:54 +00004268}
4269
Damien Miller7acefbb2014-07-18 14:11:24 +10004270/* Check if connecting to that path is permitted and connect. */
4271Channel *
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004272channel_connect_to_path(struct ssh *ssh, const char *path,
4273 char *ctype, char *rname)
Damien Miller7acefbb2014-07-18 14:11:24 +10004274{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004275 struct ssh_channels *sc = ssh->chanctxt;
4276 u_int i, permit, permit_adm = 1;
4277 ForwardPermission *fp;
Damien Miller7acefbb2014-07-18 14:11:24 +10004278
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004279 permit = sc->all_opens_permitted;
Damien Miller7acefbb2014-07-18 14:11:24 +10004280 if (!permit) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004281 for (i = 0; i < sc->num_permitted_opens; i++) {
4282 fp = &sc->permitted_opens[i];
4283 if (open_match(fp, path, PORT_STREAMLOCAL)) {
Damien Miller7acefbb2014-07-18 14:11:24 +10004284 permit = 1;
4285 break;
4286 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004287 }
Damien Miller7acefbb2014-07-18 14:11:24 +10004288 }
4289
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004290 if (sc->num_adm_permitted_opens > 0) {
Damien Miller7acefbb2014-07-18 14:11:24 +10004291 permit_adm = 0;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004292 for (i = 0; i < sc->num_adm_permitted_opens; i++) {
4293 fp = &sc->permitted_adm_opens[i];
4294 if (open_match(fp, path, PORT_STREAMLOCAL)) {
Damien Miller7acefbb2014-07-18 14:11:24 +10004295 permit_adm = 1;
4296 break;
4297 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004298 }
Damien Miller7acefbb2014-07-18 14:11:24 +10004299 }
4300
4301 if (!permit || !permit_adm) {
4302 logit("Received request to connect to path %.100s, "
4303 "but the request was denied.", path);
4304 return NULL;
4305 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004306 return connect_to(ssh, path, PORT_STREAMLOCAL, ctype, rname);
Damien Miller7acefbb2014-07-18 14:11:24 +10004307}
4308
Damien Miller0e220db2004-06-15 10:34:08 +10004309void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004310channel_send_window_changes(struct ssh *ssh)
Damien Miller0e220db2004-06-15 10:34:08 +10004311{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004312 struct ssh_channels *sc = ssh->chanctxt;
Damien Miller0e220db2004-06-15 10:34:08 +10004313 struct winsize ws;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004314 int r;
4315 u_int i;
Damien Miller0e220db2004-06-15 10:34:08 +10004316
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004317 for (i = 0; i < sc->channels_alloc; i++) {
4318 if (sc->channels[i] == NULL || !sc->channels[i]->client_tty ||
4319 sc->channels[i]->type != SSH_CHANNEL_OPEN)
Damien Miller0e220db2004-06-15 10:34:08 +10004320 continue;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004321 if (ioctl(sc->channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
Damien Miller0e220db2004-06-15 10:34:08 +10004322 continue;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004323 channel_request_start(ssh, i, "window-change", 0);
4324 if ((r = sshpkt_put_u32(ssh, (u_int)ws.ws_col)) != 0 ||
4325 (r = sshpkt_put_u32(ssh, (u_int)ws.ws_row)) != 0 ||
4326 (r = sshpkt_put_u32(ssh, (u_int)ws.ws_xpixel)) != 0 ||
4327 (r = sshpkt_put_u32(ssh, (u_int)ws.ws_ypixel)) != 0 ||
4328 (r = sshpkt_send(ssh)) != 0)
4329 fatal("%s: channel %u: send window-change: %s",
4330 __func__, i, ssh_err(r));
Damien Miller0e220db2004-06-15 10:34:08 +10004331 }
4332}
4333
markus@openbsd.org609d7a62017-09-21 19:16:53 +00004334/* Return RDYNAMIC_OPEN channel: channel allows SOCKS, but is not connected */
4335static Channel *
4336rdynamic_connect_prepare(struct ssh *ssh, char *ctype, char *rname)
4337{
4338 Channel *c;
4339 int r;
4340
4341 c = channel_new(ssh, ctype, SSH_CHANNEL_RDYNAMIC_OPEN, -1, -1, -1,
4342 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4343 c->host_port = 0;
4344 c->path = NULL;
4345
4346 /*
4347 * We need to open the channel before we have a FD,
4348 * so that we can get SOCKS header from peer.
4349 */
4350 if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
4351 (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
4352 (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
4353 (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
4354 (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
4355 fatal("%s: channel %i: confirm: %s", __func__,
4356 c->self, ssh_err(r));
4357 }
4358 return c;
4359}
4360
4361/* Return CONNECTING socket to remote host:port or local socket path */
4362static int
4363rdynamic_connect_finish(struct ssh *ssh, Channel *c)
4364{
4365 struct channel_connect cctx;
4366 int sock;
4367
4368 memset(&cctx, 0, sizeof(cctx));
4369 sock = connect_to_helper(ssh, c->path, c->host_port, SOCK_STREAM, NULL,
4370 NULL, &cctx, NULL, NULL);
4371 if (sock == -1)
4372 channel_connect_ctx_free(&cctx);
4373 else {
4374 /* similar to SSH_CHANNEL_CONNECTING but we've already sent the open */
4375 c->type = SSH_CHANNEL_RDYNAMIC_FINISH;
4376 c->connect_ctx = cctx;
4377 channel_register_fds(ssh, c, sock, sock, -1, 0, 1, 0);
4378 }
4379 return sock;
4380}
4381
Ben Lindstrome9c99912001-06-09 00:41:05 +00004382/* -- X11 forwarding */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004383
Damien Miller5428f641999-11-25 11:54:57 +11004384/*
4385 * Creates an internet domain socket for listening for X11 connections.
Ben Lindstroma9d2c892002-06-23 21:48:28 +00004386 * Returns 0 and a suitable display number for the DISPLAY variable
4387 * stored in display_numberp , or -1 if an error occurs.
Damien Miller5428f641999-11-25 11:54:57 +11004388 */
Kevin Steves366298c2001-12-19 17:58:01 +00004389int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004390x11_create_display_inet(struct ssh *ssh, int x11_display_offset,
4391 int x11_use_localhost, int single_connection,
4392 u_int *display_numberp, int **chanids)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004393{
Damien Millere7378562001-12-21 14:58:35 +11004394 Channel *nc = NULL;
Damien Milleraae6c611999-12-06 11:47:28 +11004395 int display_number, sock;
4396 u_short port;
Damien Miller34132e52000-01-14 15:45:46 +11004397 struct addrinfo hints, *ai, *aitop;
4398 char strport[NI_MAXSERV];
4399 int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004400
Darren Tuckerd3d0fa12005-10-03 18:03:05 +10004401 if (chanids == NULL)
4402 return -1;
4403
Damien Millera34a28b1999-12-14 10:47:15 +11004404 for (display_number = x11_display_offset;
Damien Miller9f0f5c62001-12-21 14:45:46 +11004405 display_number < MAX_DISPLAYS;
4406 display_number++) {
Damien Miller95def091999-11-25 00:26:21 +11004407 port = 6000 + display_number;
Damien Miller34132e52000-01-14 15:45:46 +11004408 memset(&hints, 0, sizeof(hints));
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004409 hints.ai_family = ssh->chanctxt->IPv4or6;
Damien Miller95c249f2002-02-05 12:11:34 +11004410 hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
Damien Miller34132e52000-01-14 15:45:46 +11004411 hints.ai_socktype = SOCK_STREAM;
4412 snprintf(strport, sizeof strport, "%d", port);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004413 if ((gaierr = getaddrinfo(NULL, strport,
4414 &hints, &aitop)) != 0) {
Darren Tucker4abde772007-12-29 02:43:51 +11004415 error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
Kevin Steves366298c2001-12-19 17:58:01 +00004416 return -1;
Damien Miller95def091999-11-25 00:26:21 +11004417 }
Damien Miller34132e52000-01-14 15:45:46 +11004418 for (ai = aitop; ai; ai = ai->ai_next) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004419 if (ai->ai_family != AF_INET &&
4420 ai->ai_family != AF_INET6)
Damien Miller34132e52000-01-14 15:45:46 +11004421 continue;
Darren Tucker7bd98e72010-01-10 10:31:12 +11004422 sock = socket(ai->ai_family, ai->ai_socktype,
4423 ai->ai_protocol);
Damien Miller34132e52000-01-14 15:45:46 +11004424 if (sock < 0) {
Damien Miller6480c632010-03-26 11:09:44 +11004425 if ((errno != EINVAL) && (errno != EAFNOSUPPORT)
4426#ifdef EPFNOSUPPORT
4427 && (errno != EPFNOSUPPORT)
4428#endif
4429 ) {
Damien Millere2192732000-01-17 13:22:55 +11004430 error("socket: %.100s", strerror(errno));
Damien Miller3e4dffb2004-06-15 10:27:15 +10004431 freeaddrinfo(aitop);
Kevin Steves366298c2001-12-19 17:58:01 +00004432 return -1;
Damien Millere2192732000-01-17 13:22:55 +11004433 } else {
Damien Millercb5e44a2000-09-29 12:12:36 +11004434 debug("x11_create_display_inet: Socket family %d not supported",
4435 ai->ai_family);
Damien Millere2192732000-01-17 13:22:55 +11004436 continue;
4437 }
Damien Miller34132e52000-01-14 15:45:46 +11004438 }
Damien Miller04ee0f82009-11-18 17:48:30 +11004439 if (ai->ai_family == AF_INET6)
4440 sock_set_v6only(sock);
Damien Miller4401e452008-06-12 06:05:12 +10004441 if (x11_use_localhost)
4442 channel_set_reuseaddr(sock);
Damien Miller34132e52000-01-14 15:45:46 +11004443 if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004444 debug2("%s: bind port %d: %.100s", __func__,
4445 port, strerror(errno));
Damien Miller34132e52000-01-14 15:45:46 +11004446 close(sock);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004447 for (n = 0; n < num_socks; n++)
Damien Miller34132e52000-01-14 15:45:46 +11004448 close(socks[n]);
Damien Miller34132e52000-01-14 15:45:46 +11004449 num_socks = 0;
4450 break;
4451 }
4452 socks[num_socks++] = sock;
4453 if (num_socks == NUM_SOCKS)
4454 break;
Damien Miller95def091999-11-25 00:26:21 +11004455 }
Ben Lindstrom87b147f2001-01-25 00:41:12 +00004456 freeaddrinfo(aitop);
Damien Miller34132e52000-01-14 15:45:46 +11004457 if (num_socks > 0)
4458 break;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004459 }
Damien Miller95def091999-11-25 00:26:21 +11004460 if (display_number >= MAX_DISPLAYS) {
4461 error("Failed to allocate internet-domain X11 display socket.");
Kevin Steves366298c2001-12-19 17:58:01 +00004462 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004463 }
Damien Miller95def091999-11-25 00:26:21 +11004464 /* Start listening for connections on the socket. */
Damien Miller34132e52000-01-14 15:45:46 +11004465 for (n = 0; n < num_socks; n++) {
4466 sock = socks[n];
Darren Tucker3175eb92003-12-09 19:15:11 +11004467 if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
Damien Miller34132e52000-01-14 15:45:46 +11004468 error("listen: %.100s", strerror(errno));
Damien Miller34132e52000-01-14 15:45:46 +11004469 close(sock);
Kevin Steves366298c2001-12-19 17:58:01 +00004470 return -1;
Damien Miller34132e52000-01-14 15:45:46 +11004471 }
Damien Miller95def091999-11-25 00:26:21 +11004472 }
Damien Miller34132e52000-01-14 15:45:46 +11004473
Damien Miller34132e52000-01-14 15:45:46 +11004474 /* Allocate a channel for each socket. */
Damien Miller07d86be2006-03-26 14:19:21 +11004475 *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
Damien Miller34132e52000-01-14 15:45:46 +11004476 for (n = 0; n < num_socks; n++) {
4477 sock = socks[n];
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004478 nc = channel_new(ssh, "x11 listener",
Damien Millerbd483e72000-04-30 10:00:53 +10004479 SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
4480 CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
Damien Millerb1ca8bb2003-05-14 13:45:42 +10004481 0, "X11 inet listener", 1);
Damien Miller699d0032002-02-08 22:07:16 +11004482 nc->single_connection = single_connection;
Darren Tuckerd3d0fa12005-10-03 18:03:05 +10004483 (*chanids)[n] = nc->self;
Damien Miller34132e52000-01-14 15:45:46 +11004484 }
Darren Tuckerd3d0fa12005-10-03 18:03:05 +10004485 (*chanids)[n] = -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004486
Kevin Steves366298c2001-12-19 17:58:01 +00004487 /* Return the display number for the DISPLAY environment variable. */
Ben Lindstroma9d2c892002-06-23 21:48:28 +00004488 *display_numberp = display_number;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004489 return 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004490}
4491
Ben Lindstrombba81212001-06-25 05:01:22 +00004492static int
Damien Miller819dbb62009-01-21 16:46:26 +11004493connect_local_xsocket_path(const char *pathname)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004494{
Damien Miller95def091999-11-25 00:26:21 +11004495 int sock;
4496 struct sockaddr_un addr;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004497
Damien Miller3afe3752001-12-21 12:39:51 +11004498 sock = socket(AF_UNIX, SOCK_STREAM, 0);
4499 if (sock < 0)
4500 error("socket: %.100s", strerror(errno));
4501 memset(&addr, 0, sizeof(addr));
4502 addr.sun_family = AF_UNIX;
Damien Miller819dbb62009-01-21 16:46:26 +11004503 strlcpy(addr.sun_path, pathname, sizeof addr.sun_path);
Damien Miller90967402006-03-26 14:07:26 +11004504 if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
Damien Miller3afe3752001-12-21 12:39:51 +11004505 return sock;
4506 close(sock);
Damien Miller95def091999-11-25 00:26:21 +11004507 error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
4508 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004509}
4510
Damien Miller819dbb62009-01-21 16:46:26 +11004511static int
4512connect_local_xsocket(u_int dnr)
4513{
4514 char buf[1024];
4515 snprintf(buf, sizeof buf, _PATH_UNIX_X, dnr);
4516 return connect_local_xsocket_path(buf);
4517}
4518
Darren Tuckerda39b092017-03-10 13:22:32 +11004519#ifdef __APPLE__
4520static int
4521is_path_to_xsocket(const char *display, char *path, size_t pathlen)
4522{
4523 struct stat sbuf;
4524
4525 if (strlcpy(path, display, pathlen) >= pathlen) {
4526 error("%s: display path too long", __func__);
4527 return 0;
4528 }
4529 if (display[0] != '/')
4530 return 0;
4531 if (stat(path, &sbuf) == 0) {
4532 return 1;
4533 } else {
4534 char *dot = strrchr(path, '.');
4535 if (dot != NULL) {
4536 *dot = '\0';
4537 if (stat(path, &sbuf) == 0) {
4538 return 1;
4539 }
4540 }
4541 }
4542 return 0;
4543}
4544#endif
4545
Damien Millerbd483e72000-04-30 10:00:53 +10004546int
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004547x11_connect_display(struct ssh *ssh)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004548{
Damien Miller57c4e872006-03-31 23:11:07 +11004549 u_int display_number;
Damien Miller95def091999-11-25 00:26:21 +11004550 const char *display;
Damien Millerbd483e72000-04-30 10:00:53 +10004551 char buf[1024], *cp;
Damien Miller34132e52000-01-14 15:45:46 +11004552 struct addrinfo hints, *ai, *aitop;
4553 char strport[NI_MAXSERV];
Damien Miller57c4e872006-03-31 23:11:07 +11004554 int gaierr, sock = 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004555
Damien Miller95def091999-11-25 00:26:21 +11004556 /* Try to open a socket for the local X server. */
4557 display = getenv("DISPLAY");
4558 if (!display) {
4559 error("DISPLAY not set.");
Damien Millerbd483e72000-04-30 10:00:53 +10004560 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004561 }
Damien Miller5428f641999-11-25 11:54:57 +11004562 /*
4563 * Now we decode the value of the DISPLAY variable and make a
4564 * connection to the real X server.
4565 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004566
Damien Miller819dbb62009-01-21 16:46:26 +11004567#ifdef __APPLE__
Darren Tuckerda39b092017-03-10 13:22:32 +11004568 /* Check if display is a path to a socket (as set by launchd). */
4569 {
4570 char path[PATH_MAX];
Damien Miller819dbb62009-01-21 16:46:26 +11004571
Darren Tuckerda39b092017-03-10 13:22:32 +11004572 if (is_path_to_xsocket(display, path, sizeof(path))) {
4573 debug("x11_connect_display: $DISPLAY is launchd");
4574
4575 /* Create a socket. */
4576 sock = connect_local_xsocket_path(path);
4577 if (sock < 0)
4578 return -1;
4579
4580 /* OK, we now have a connection to the display. */
4581 return sock;
4582 }
Damien Miller819dbb62009-01-21 16:46:26 +11004583 }
4584#endif
Damien Miller5428f641999-11-25 11:54:57 +11004585 /*
4586 * Check if it is a unix domain socket. Unix domain displays are in
4587 * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
4588 */
Damien Miller95def091999-11-25 00:26:21 +11004589 if (strncmp(display, "unix:", 5) == 0 ||
4590 display[0] == ':') {
4591 /* Connect to the unix domain socket. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004592 if (sscanf(strrchr(display, ':') + 1, "%u",
4593 &display_number) != 1) {
4594 error("Could not parse display number from DISPLAY: "
4595 "%.100s", display);
Damien Millerbd483e72000-04-30 10:00:53 +10004596 return -1;
Damien Miller95def091999-11-25 00:26:21 +11004597 }
4598 /* Create a socket. */
4599 sock = connect_local_xsocket(display_number);
4600 if (sock < 0)
Damien Millerbd483e72000-04-30 10:00:53 +10004601 return -1;
Damien Miller95def091999-11-25 00:26:21 +11004602
4603 /* OK, we now have a connection to the display. */
Damien Millerbd483e72000-04-30 10:00:53 +10004604 return sock;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004605 }
Damien Miller5428f641999-11-25 11:54:57 +11004606 /*
4607 * Connect to an inet socket. The DISPLAY value is supposedly
4608 * hostname:d[.s], where hostname may also be numeric IP address.
4609 */
Ben Lindstromccd8d072001-12-07 17:26:48 +00004610 strlcpy(buf, display, sizeof(buf));
Damien Miller95def091999-11-25 00:26:21 +11004611 cp = strchr(buf, ':');
4612 if (!cp) {
4613 error("Could not find ':' in DISPLAY: %.100s", display);
Damien Millerbd483e72000-04-30 10:00:53 +10004614 return -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004615 }
Damien Miller95def091999-11-25 00:26:21 +11004616 *cp = 0;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004617 /*
4618 * buf now contains the host name. But first we parse the
4619 * display number.
4620 */
Damien Miller57c4e872006-03-31 23:11:07 +11004621 if (sscanf(cp + 1, "%u", &display_number) != 1) {
Damien Miller95def091999-11-25 00:26:21 +11004622 error("Could not parse display number from DISPLAY: %.100s",
Damien Miller9f0f5c62001-12-21 14:45:46 +11004623 display);
Damien Millerbd483e72000-04-30 10:00:53 +10004624 return -1;
Damien Miller95def091999-11-25 00:26:21 +11004625 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004626
Damien Miller34132e52000-01-14 15:45:46 +11004627 /* Look up the host address */
4628 memset(&hints, 0, sizeof(hints));
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004629 hints.ai_family = ssh->chanctxt->IPv4or6;
Damien Miller34132e52000-01-14 15:45:46 +11004630 hints.ai_socktype = SOCK_STREAM;
Damien Miller57c4e872006-03-31 23:11:07 +11004631 snprintf(strport, sizeof strport, "%u", 6000 + display_number);
Damien Miller34132e52000-01-14 15:45:46 +11004632 if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
Darren Tucker4abde772007-12-29 02:43:51 +11004633 error("%.100s: unknown host. (%s)", buf,
4634 ssh_gai_strerror(gaierr));
Damien Millerbd483e72000-04-30 10:00:53 +10004635 return -1;
Damien Miller95def091999-11-25 00:26:21 +11004636 }
Damien Miller34132e52000-01-14 15:45:46 +11004637 for (ai = aitop; ai; ai = ai->ai_next) {
4638 /* Create a socket. */
Darren Tucker7bd98e72010-01-10 10:31:12 +11004639 sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
Damien Miller34132e52000-01-14 15:45:46 +11004640 if (sock < 0) {
Damien Millerfbdeece2003-09-02 22:52:31 +10004641 debug2("socket: %.100s", strerror(errno));
Damien Millerb38eff82000-04-01 11:09:21 +10004642 continue;
4643 }
4644 /* Connect it to the display. */
4645 if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
Damien Miller57c4e872006-03-31 23:11:07 +11004646 debug2("connect %.100s port %u: %.100s", buf,
Damien Millerb38eff82000-04-01 11:09:21 +10004647 6000 + display_number, strerror(errno));
4648 close(sock);
4649 continue;
4650 }
4651 /* Success */
4652 break;
Damien Miller34132e52000-01-14 15:45:46 +11004653 }
Damien Miller34132e52000-01-14 15:45:46 +11004654 freeaddrinfo(aitop);
4655 if (!ai) {
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004656 error("connect %.100s port %u: %.100s", buf,
4657 6000 + display_number, strerror(errno));
Damien Millerbd483e72000-04-30 10:00:53 +10004658 return -1;
Damien Miller95def091999-11-25 00:26:21 +11004659 }
Damien Miller398e1cf2002-02-05 11:52:13 +11004660 set_nodelay(sock);
Damien Millerbd483e72000-04-30 10:00:53 +10004661 return sock;
4662}
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004663
Damien Millerbd483e72000-04-30 10:00:53 +10004664/*
Damien Miller5428f641999-11-25 11:54:57 +11004665 * Requests forwarding of X11 connections, generates fake authentication
4666 * data, and enables authentication spoofing.
Ben Lindstrome9c99912001-06-09 00:41:05 +00004667 * This should be called in the client only.
Damien Miller5428f641999-11-25 11:54:57 +11004668 */
Damien Miller4af51302000-04-16 11:18:38 +10004669void
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004670x11_request_forwarding_with_spoofing(struct ssh *ssh, int client_session_id,
4671 const char *disp, const char *proto, const char *data, int want_reply)
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004672{
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004673 struct ssh_channels *sc = ssh->chanctxt;
Ben Lindstrom46c16222000-12-22 01:43:59 +00004674 u_int data_len = (u_int) strlen(data) / 2;
Damien Miller13390022005-07-06 09:44:19 +10004675 u_int i, value;
Damien Miller95def091999-11-25 00:26:21 +11004676 const char *cp;
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004677 char *new_data;
4678 int r, screen_number;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004679
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004680 if (sc->x11_saved_display == NULL)
4681 sc->x11_saved_display = xstrdup(disp);
4682 else if (strcmp(disp, sc->x11_saved_display) != 0) {
Damien Miller13390022005-07-06 09:44:19 +10004683 error("x11_request_forwarding_with_spoofing: different "
4684 "$DISPLAY already forwarded");
4685 return;
4686 }
4687
Damien Millerd5fe0ba2006-08-30 11:07:39 +10004688 cp = strchr(disp, ':');
Damien Miller95def091999-11-25 00:26:21 +11004689 if (cp)
4690 cp = strchr(cp, '.');
4691 if (cp)
Damien Miller08d61502006-03-26 14:28:32 +11004692 screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
Damien Miller95def091999-11-25 00:26:21 +11004693 else
4694 screen_number = 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004695
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004696 if (sc->x11_saved_proto == NULL) {
Damien Miller13390022005-07-06 09:44:19 +10004697 /* Save protocol name. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004698 sc->x11_saved_proto = xstrdup(proto);
natano@openbsd.org49271082016-09-19 07:52:42 +00004699
4700 /* Extract real authentication data. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004701 sc->x11_saved_data = xmalloc(data_len);
Damien Miller13390022005-07-06 09:44:19 +10004702 for (i = 0; i < data_len; i++) {
4703 if (sscanf(data + 2 * i, "%2x", &value) != 1)
4704 fatal("x11_request_forwarding: bad "
4705 "authentication data: %.100s", data);
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004706 sc->x11_saved_data[i] = value;
Damien Miller13390022005-07-06 09:44:19 +10004707 }
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004708 sc->x11_saved_data_len = data_len;
natano@openbsd.org49271082016-09-19 07:52:42 +00004709
4710 /* Generate fake data of the same length. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004711 sc->x11_fake_data = xmalloc(data_len);
4712 arc4random_buf(sc->x11_fake_data, data_len);
4713 sc->x11_fake_data_len = data_len;
Damien Miller95def091999-11-25 00:26:21 +11004714 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004715
Damien Miller95def091999-11-25 00:26:21 +11004716 /* Convert the fake data into hex. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004717 new_data = tohex(sc->x11_fake_data, data_len);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004718
Damien Miller95def091999-11-25 00:26:21 +11004719 /* Send the request packet. */
djm@openbsd.orgdbee4112017-09-12 06:32:07 +00004720 channel_request_start(ssh, client_session_id, "x11-req", want_reply);
4721 if ((r = sshpkt_put_u8(ssh, 0)) != 0 || /* bool: single connection */
4722 (r = sshpkt_put_cstring(ssh, proto)) != 0 ||
4723 (r = sshpkt_put_cstring(ssh, new_data)) != 0 ||
4724 (r = sshpkt_put_u32(ssh, screen_number)) != 0 ||
4725 (r = sshpkt_send(ssh)) != 0 ||
4726 (r = ssh_packet_write_wait(ssh)) != 0)
4727 fatal("%s: send x11-req: %s", __func__, ssh_err(r));
Darren Tuckera627d422013-06-02 07:31:17 +10004728 free(new_data);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10004729}