blob: 912f625015d6b428a4d9cb73ca6cbf3791724a46 [file] [log] [blame]
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001/*
Damien Miller95def091999-11-25 00:26:21 +11002 * Author: Tatu Ylonen <ylo@cs.hut.fi>
3 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
4 * All rights reserved
Damien Miller95def091999-11-25 00:26:21 +11005 * Server main loop for handling the interactive session.
Damien Millere4340be2000-09-16 13:29:08 +11006 *
7 * As far as I am concerned, the code I have written for this software
8 * can be used freely for any purpose. Any derived versions of this
9 * software must be clearly marked as such, and if the derived work is
10 * incompatible with the protocol description in the RFC file, it must be
11 * called by a name other than "ssh" or "Secure Shell".
12 *
Damien Millerefb4afe2000-04-12 18:45:05 +100013 * SSH2 support by Markus Friedl.
Ben Lindstrom44697232001-07-04 03:32:30 +000014 * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
Damien Millere4340be2000-09-16 13:29:08 +110015 *
16 * Redistribution and use in source and binary forms, with or without
17 * modification, are permitted provided that the following conditions
18 * are met:
19 * 1. Redistributions of source code must retain the above copyright
20 * notice, this list of conditions and the following disclaimer.
21 * 2. Redistributions in binary form must reproduce the above copyright
22 * notice, this list of conditions and the following disclaimer in the
23 * documentation and/or other materials provided with the distribution.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
26 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
27 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
28 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
29 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
30 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
31 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
32 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
Damien Millerefb4afe2000-04-12 18:45:05 +100035 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +100036
37#include "includes.h"
Ben Lindstrom4fed2be2002-06-25 23:17:36 +000038RCSID("$OpenBSD: serverloop.c,v 1.103 2002/06/24 14:33:27 markus Exp $");
Damien Miller69b69aa2000-10-28 14:19:58 +110039
Damien Millerd4a8b7e1999-10-27 13:42:43 +100040#include "xmalloc.h"
Damien Millerd4a8b7e1999-10-27 13:42:43 +100041#include "packet.h"
42#include "buffer.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000043#include "log.h"
Damien Millerd4a8b7e1999-10-27 13:42:43 +100044#include "servconf.h"
Ben Lindstromd95c09c2001-02-18 19:13:33 +000045#include "sshpty.h"
Ben Lindstromc7637672001-06-09 00:36:26 +000046#include "channels.h"
Damien Millerb38eff82000-04-01 11:09:21 +100047#include "compat.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000048#include "ssh1.h"
Damien Millerefb4afe2000-04-12 18:45:05 +100049#include "ssh2.h"
Ben Lindstromdb65e8f2001-01-19 04:26:52 +000050#include "auth.h"
Damien Millerefb4afe2000-04-12 18:45:05 +100051#include "session.h"
Damien Millerb38eff82000-04-01 11:09:21 +100052#include "dispatch.h"
Damien Millerf6d9e222000-06-18 14:50:44 +100053#include "auth-options.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000054#include "serverloop.h"
55#include "misc.h"
Ben Lindstrom8ac91062001-04-04 17:57:54 +000056#include "kex.h"
Damien Millerd4a8b7e1999-10-27 13:42:43 +100057
Damien Miller50a41ed2000-10-16 12:14:42 +110058extern ServerOptions options;
59
Ben Lindstrom8ac91062001-04-04 17:57:54 +000060/* XXX */
61extern Kex *xxx_kex;
Ben Lindstrombddd5512001-07-04 04:53:53 +000062static Authctxt *xxx_authctxt;
Ben Lindstrom8ac91062001-04-04 17:57:54 +000063
Damien Millerd4a8b7e1999-10-27 13:42:43 +100064static Buffer stdin_buffer; /* Buffer for stdin data. */
65static Buffer stdout_buffer; /* Buffer for stdout data. */
66static Buffer stderr_buffer; /* Buffer for stderr data. */
67static int fdin; /* Descriptor for stdin (for writing) */
68static int fdout; /* Descriptor for stdout (for reading);
69 May be same number as fdin. */
70static int fderr; /* Descriptor for stderr. May be -1. */
71static long stdin_bytes = 0; /* Number of bytes written to stdin. */
72static long stdout_bytes = 0; /* Number of stdout bytes sent to client. */
73static long stderr_bytes = 0; /* Number of stderr bytes sent to client. */
74static long fdout_bytes = 0; /* Number of stdout bytes read from program. */
75static int stdin_eof = 0; /* EOF message received from client. */
76static int fdout_eof = 0; /* EOF encountered reading from fdout. */
77static int fderr_eof = 0; /* EOF encountered readung from fderr. */
Damien Miller225736c2001-02-19 21:51:08 +110078static int fdin_is_tty = 0; /* fdin points to a tty. */
Damien Millerd4a8b7e1999-10-27 13:42:43 +100079static int connection_in; /* Connection to client (input). */
80static int connection_out; /* Connection to client (output). */
Ben Lindstrome34ab4c2001-04-07 01:12:11 +000081static int connection_closed = 0; /* Connection to client closed. */
82static u_int buffer_high; /* "Soft" max buffer size. */
Damien Miller8c3902a2001-10-10 15:01:40 +100083static int client_alive_timeouts = 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +100084
Damien Miller5428f641999-11-25 11:54:57 +110085/*
86 * This SIGCHLD kludge is used to detect when the child exits. The server
87 * will exit after that, as soon as forwarded connections have terminated.
88 */
Ben Lindstrombba81212001-06-25 05:01:22 +000089
Ben Lindstrom5e71c542001-12-06 16:48:14 +000090static volatile sig_atomic_t child_terminated = 0; /* The child has terminated. */
Damien Millerd4a8b7e1999-10-27 13:42:43 +100091
Ben Lindstrombba81212001-06-25 05:01:22 +000092/* prototypes */
93static void server_init_dispatch(void);
Damien Millerb38eff82000-04-01 11:09:21 +100094
Damien Millerf6681a32001-12-21 14:53:11 +110095/*
96 * we write to this pipe if a SIGCHLD is caught in order to avoid
97 * the race between select() and child_terminated
98 */
99static int notify_pipe[2];
100static void
101notify_setup(void)
102{
103 if (pipe(notify_pipe) < 0) {
104 error("pipe(notify_pipe) failed %s", strerror(errno));
105 } else if ((fcntl(notify_pipe[0], F_SETFD, 1) == -1) ||
106 (fcntl(notify_pipe[1], F_SETFD, 1) == -1)) {
107 error("fcntl(notify_pipe, F_SETFD) failed %s", strerror(errno));
108 close(notify_pipe[0]);
109 close(notify_pipe[1]);
110 } else {
111 set_nonblock(notify_pipe[0]);
112 set_nonblock(notify_pipe[1]);
113 return;
114 }
115 notify_pipe[0] = -1; /* read end */
116 notify_pipe[1] = -1; /* write end */
117}
118static void
119notify_parent(void)
120{
121 if (notify_pipe[1] != -1)
122 write(notify_pipe[1], "", 1);
123}
124static void
125notify_prepare(fd_set *readset)
126{
127 if (notify_pipe[0] != -1)
128 FD_SET(notify_pipe[0], readset);
129}
130static void
131notify_done(fd_set *readset)
132{
133 char c;
134
135 if (notify_pipe[0] != -1 && FD_ISSET(notify_pipe[0], readset))
136 while (read(notify_pipe[0], &c, 1) != -1)
137 debug2("notify_done: reading");
138}
139
Ben Lindstrombba81212001-06-25 05:01:22 +0000140static void
Damien Miller95def091999-11-25 00:26:21 +1100141sigchld_handler(int sig)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000142{
Damien Miller95def091999-11-25 00:26:21 +1100143 int save_errno = errno;
Damien Millerefb4afe2000-04-12 18:45:05 +1000144 debug("Received SIGCHLD.");
145 child_terminated = 1;
Ben Lindstromec46e0b2001-06-09 01:27:31 +0000146 mysignal(SIGCHLD, sigchld_handler);
Damien Millerf6681a32001-12-21 14:53:11 +1100147 notify_parent();
Damien Millerefb4afe2000-04-12 18:45:05 +1000148 errno = save_errno;
149}
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000150
Damien Miller95def091999-11-25 00:26:21 +1100151/*
Damien Miller95def091999-11-25 00:26:21 +1100152 * Make packets from buffered stderr data, and buffer it for sending
153 * to the client.
154 */
Ben Lindstrombba81212001-06-25 05:01:22 +0000155static void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000156make_packets_from_stderr_data(void)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000157{
Damien Miller95def091999-11-25 00:26:21 +1100158 int len;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000159
Damien Miller95def091999-11-25 00:26:21 +1100160 /* Send buffered stderr data to the client. */
161 while (buffer_len(&stderr_buffer) > 0 &&
Damien Miller037a0dc1999-12-07 15:38:31 +1100162 packet_not_very_much_data_to_write()) {
Damien Miller95def091999-11-25 00:26:21 +1100163 len = buffer_len(&stderr_buffer);
164 if (packet_is_interactive()) {
165 if (len > 512)
166 len = 512;
167 } else {
168 /* Keep the packets at reasonable size. */
169 if (len > packet_get_maxsize())
170 len = packet_get_maxsize();
171 }
172 packet_start(SSH_SMSG_STDERR_DATA);
173 packet_put_string(buffer_ptr(&stderr_buffer), len);
174 packet_send();
175 buffer_consume(&stderr_buffer, len);
176 stderr_bytes += len;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000177 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000178}
179
Damien Miller95def091999-11-25 00:26:21 +1100180/*
181 * Make packets from buffered stdout data, and buffer it for sending to the
182 * client.
183 */
Ben Lindstrombba81212001-06-25 05:01:22 +0000184static void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000185make_packets_from_stdout_data(void)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000186{
Damien Miller95def091999-11-25 00:26:21 +1100187 int len;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000188
Damien Miller95def091999-11-25 00:26:21 +1100189 /* Send buffered stdout data to the client. */
190 while (buffer_len(&stdout_buffer) > 0 &&
Damien Miller037a0dc1999-12-07 15:38:31 +1100191 packet_not_very_much_data_to_write()) {
Damien Miller95def091999-11-25 00:26:21 +1100192 len = buffer_len(&stdout_buffer);
193 if (packet_is_interactive()) {
194 if (len > 512)
195 len = 512;
196 } else {
197 /* Keep the packets at reasonable size. */
198 if (len > packet_get_maxsize())
Kevin Stevesef4eea92001-02-05 12:42:17 +0000199 len = packet_get_maxsize();
Damien Miller95def091999-11-25 00:26:21 +1100200 }
201 packet_start(SSH_SMSG_STDOUT_DATA);
202 packet_put_string(buffer_ptr(&stdout_buffer), len);
203 packet_send();
204 buffer_consume(&stdout_buffer, len);
205 stdout_bytes += len;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000206 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000207}
208
Damien Miller8c3902a2001-10-10 15:01:40 +1000209static void
210client_alive_check(void)
211{
Damien Miller056cf732002-01-22 23:21:39 +1100212 static int had_channel = 0;
Damien Miller8c3902a2001-10-10 15:01:40 +1000213 int id;
214
Damien Miller056cf732002-01-22 23:21:39 +1100215 id = channel_find_open();
216 if (id == -1) {
217 if (!had_channel)
218 return;
219 packet_disconnect("No open channels after timeout!");
220 }
221 had_channel = 1;
222
Damien Miller8c3902a2001-10-10 15:01:40 +1000223 /* timeout, check to see how many we have had */
224 if (++client_alive_timeouts > options.client_alive_count_max)
225 packet_disconnect("Timeout, your session not responding.");
226
Damien Miller8c3902a2001-10-10 15:01:40 +1000227 /*
228 * send a bogus channel request with "wantreply",
229 * we should get back a failure
230 */
231 channel_request_start(id, "keepalive@openssh.com", 1);
232 packet_send();
233}
234
Damien Miller95def091999-11-25 00:26:21 +1100235/*
236 * Sleep in select() until we can do something. This will initialize the
237 * select masks. Upon return, the masks will indicate which descriptors
238 * have data or can accept data. Optionally, a maximum time can be specified
239 * for the duration of the wait (0 = infinite).
240 */
Ben Lindstrombba81212001-06-25 05:01:22 +0000241static void
Damien Miller5e953212001-01-30 09:14:00 +1100242wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000243 int *nallocp, u_int max_time_milliseconds)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000244{
Damien Miller95def091999-11-25 00:26:21 +1100245 struct timeval tv, *tvp;
246 int ret;
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000247 int client_alive_scheduled = 0;
248
249 /*
Damien Miller9f0f5c62001-12-21 14:45:46 +1100250 * if using client_alive, set the max timeout accordingly,
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000251 * and indicate that this particular timeout was for client
252 * alive by setting the client_alive_scheduled flag.
253 *
254 * this could be randomized somewhat to make traffic
Damien Miller9f0f5c62001-12-21 14:45:46 +1100255 * analysis more difficult, but we're not doing it yet.
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000256 */
Ben Lindstrom36857f62001-07-18 15:48:57 +0000257 if (compat20 &&
258 max_time_milliseconds == 0 && options.client_alive_interval) {
Ben Lindstrom2f0304c2001-04-29 19:49:14 +0000259 client_alive_scheduled = 1;
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000260 max_time_milliseconds = options.client_alive_interval * 1000;
Ben Lindstrom36857f62001-07-18 15:48:57 +0000261 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000262
Damien Miller5e953212001-01-30 09:14:00 +1100263 /* Allocate and update select() masks for channel descriptors. */
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000264 channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, 0);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000265
Damien Millerefb4afe2000-04-12 18:45:05 +1000266 if (compat20) {
Damien Milleraf5f2e62001-10-10 15:01:16 +1000267#if 0
Damien Millere247cc42000-05-07 12:03:14 +1000268 /* wrong: bad condition XXX */
Damien Millerefb4afe2000-04-12 18:45:05 +1000269 if (channel_not_very_much_buffered_data())
Damien Milleraf5f2e62001-10-10 15:01:16 +1000270#endif
271 FD_SET(connection_in, *readsetp);
Damien Millerefb4afe2000-04-12 18:45:05 +1000272 } else {
Damien Millerb1715dc2000-05-30 13:44:51 +1000273 /*
274 * Read packets from the client unless we have too much
275 * buffered stdin or channel data.
276 */
277 if (buffer_len(&stdin_buffer) < buffer_high &&
Damien Millerefb4afe2000-04-12 18:45:05 +1000278 channel_not_very_much_buffered_data())
Damien Miller5e953212001-01-30 09:14:00 +1100279 FD_SET(connection_in, *readsetp);
Damien Millerb1715dc2000-05-30 13:44:51 +1000280 /*
281 * If there is not too much data already buffered going to
282 * the client, try to get some more data from the program.
283 */
284 if (packet_not_very_much_data_to_write()) {
285 if (!fdout_eof)
Damien Miller5e953212001-01-30 09:14:00 +1100286 FD_SET(fdout, *readsetp);
Damien Millerb1715dc2000-05-30 13:44:51 +1000287 if (!fderr_eof)
Damien Miller5e953212001-01-30 09:14:00 +1100288 FD_SET(fderr, *readsetp);
Damien Millerb1715dc2000-05-30 13:44:51 +1000289 }
290 /*
291 * If we have buffered data, try to write some of that data
292 * to the program.
293 */
294 if (fdin != -1 && buffer_len(&stdin_buffer) > 0)
Damien Miller5e953212001-01-30 09:14:00 +1100295 FD_SET(fdin, *writesetp);
Damien Millerefb4afe2000-04-12 18:45:05 +1000296 }
Damien Millerf6681a32001-12-21 14:53:11 +1100297 notify_prepare(*readsetp);
Damien Miller95def091999-11-25 00:26:21 +1100298
Damien Miller5428f641999-11-25 11:54:57 +1100299 /*
300 * If we have buffered packet data going to the client, mark that
301 * descriptor.
302 */
Damien Miller95def091999-11-25 00:26:21 +1100303 if (packet_have_data_to_write())
Damien Miller5e953212001-01-30 09:14:00 +1100304 FD_SET(connection_out, *writesetp);
Damien Miller95def091999-11-25 00:26:21 +1100305
Damien Miller5428f641999-11-25 11:54:57 +1100306 /*
307 * If child has terminated and there is enough buffer space to read
308 * from it, then read as much as is available and exit.
309 */
Damien Miller95def091999-11-25 00:26:21 +1100310 if (child_terminated && packet_not_very_much_data_to_write())
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000311 if (max_time_milliseconds == 0 || client_alive_scheduled)
Damien Miller95def091999-11-25 00:26:21 +1100312 max_time_milliseconds = 100;
313
314 if (max_time_milliseconds == 0)
315 tvp = NULL;
316 else {
317 tv.tv_sec = max_time_milliseconds / 1000;
318 tv.tv_usec = 1000 * (max_time_milliseconds % 1000);
319 tvp = &tv;
320 }
321
322 /* Wait for something to happen, or the timeout to expire. */
Damien Miller5e953212001-01-30 09:14:00 +1100323 ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
Damien Miller95def091999-11-25 00:26:21 +1100324
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000325 if (ret == -1) {
Damien Miller79faeff2001-11-12 11:06:32 +1100326 memset(*readsetp, 0, *nallocp);
327 memset(*writesetp, 0, *nallocp);
Damien Miller95def091999-11-25 00:26:21 +1100328 if (errno != EINTR)
329 error("select: %.100s", strerror(errno));
Damien Miller3ec27592001-10-12 11:35:04 +1000330 } else if (ret == 0 && client_alive_scheduled)
Damien Miller8c3902a2001-10-10 15:01:40 +1000331 client_alive_check();
Damien Millerf6681a32001-12-21 14:53:11 +1100332
333 notify_done(*readsetp);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000334}
335
Damien Miller95def091999-11-25 00:26:21 +1100336/*
337 * Processes input from the client and the program. Input data is stored
338 * in buffers and processed later.
339 */
Ben Lindstrombba81212001-06-25 05:01:22 +0000340static void
Damien Miller95def091999-11-25 00:26:21 +1100341process_input(fd_set * readset)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000342{
Damien Miller95def091999-11-25 00:26:21 +1100343 int len;
344 char buf[16384];
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000345
Damien Miller95def091999-11-25 00:26:21 +1100346 /* Read and buffer any input data from the client. */
347 if (FD_ISSET(connection_in, readset)) {
348 len = read(connection_in, buf, sizeof(buf));
349 if (len == 0) {
350 verbose("Connection closed by remote host.");
Ben Lindstrome34ab4c2001-04-07 01:12:11 +0000351 connection_closed = 1;
352 if (compat20)
353 return;
Damien Miller95def091999-11-25 00:26:21 +1100354 fatal_cleanup();
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000355 } else if (len < 0) {
356 if (errno != EINTR && errno != EAGAIN) {
357 verbose("Read error from remote host: %.100s", strerror(errno));
358 fatal_cleanup();
359 }
360 } else {
361 /* Buffer any received data. */
362 packet_process_incoming(buf, len);
Damien Miller95def091999-11-25 00:26:21 +1100363 }
Damien Miller95def091999-11-25 00:26:21 +1100364 }
Damien Millerefb4afe2000-04-12 18:45:05 +1000365 if (compat20)
366 return;
367
Damien Miller95def091999-11-25 00:26:21 +1100368 /* Read and buffer any available stdout data from the program. */
369 if (!fdout_eof && FD_ISSET(fdout, readset)) {
370 len = read(fdout, buf, sizeof(buf));
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000371 if (len < 0 && (errno == EINTR || errno == EAGAIN)) {
372 /* do nothing */
373 } else if (len <= 0) {
Damien Miller95def091999-11-25 00:26:21 +1100374 fdout_eof = 1;
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000375 } else {
Damien Miller95def091999-11-25 00:26:21 +1100376 buffer_append(&stdout_buffer, buf, len);
377 fdout_bytes += len;
378 }
379 }
380 /* Read and buffer any available stderr data from the program. */
381 if (!fderr_eof && FD_ISSET(fderr, readset)) {
382 len = read(fderr, buf, sizeof(buf));
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000383 if (len < 0 && (errno == EINTR || errno == EAGAIN)) {
384 /* do nothing */
385 } else if (len <= 0) {
Damien Miller95def091999-11-25 00:26:21 +1100386 fderr_eof = 1;
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000387 } else {
Damien Miller95def091999-11-25 00:26:21 +1100388 buffer_append(&stderr_buffer, buf, len);
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000389 }
Damien Miller95def091999-11-25 00:26:21 +1100390 }
391}
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000392
Damien Miller95def091999-11-25 00:26:21 +1100393/*
394 * Sends data from internal buffers to client program stdin.
395 */
Ben Lindstrombba81212001-06-25 05:01:22 +0000396static void
Damien Miller95def091999-11-25 00:26:21 +1100397process_output(fd_set * writeset)
398{
Ben Lindstromaa630de2001-02-10 23:44:47 +0000399 struct termios tio;
Ben Lindstrom6d218f42001-09-18 05:53:12 +0000400 u_char *data;
401 u_int dlen;
Damien Miller95def091999-11-25 00:26:21 +1100402 int len;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000403
Damien Miller95def091999-11-25 00:26:21 +1100404 /* Write buffered data to program stdin. */
Damien Millerefb4afe2000-04-12 18:45:05 +1000405 if (!compat20 && fdin != -1 && FD_ISSET(fdin, writeset)) {
Ben Lindstrom6d218f42001-09-18 05:53:12 +0000406 data = buffer_ptr(&stdin_buffer);
407 dlen = buffer_len(&stdin_buffer);
408 len = write(fdin, data, dlen);
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000409 if (len < 0 && (errno == EINTR || errno == EAGAIN)) {
410 /* do nothing */
411 } else if (len <= 0) {
Damien Millerb38eff82000-04-01 11:09:21 +1000412 if (fdin != fdout)
Damien Miller95def091999-11-25 00:26:21 +1100413 close(fdin);
414 else
415 shutdown(fdin, SHUT_WR); /* We will no longer send. */
Damien Miller95def091999-11-25 00:26:21 +1100416 fdin = -1;
417 } else {
Ben Lindstromaa630de2001-02-10 23:44:47 +0000418 /* Successful write. */
Ben Lindstrom6d218f42001-09-18 05:53:12 +0000419 if (fdin_is_tty && dlen >= 1 && data[0] != '\r' &&
420 tcgetattr(fdin, &tio) == 0 &&
Damien Miller79438cc2001-02-16 12:34:57 +1100421 !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
Kevin Stevesb7f036f2001-02-15 17:27:15 +0000422 /*
423 * Simulate echo to reduce the impact of
424 * traffic analysis
425 */
Ben Lindstrome229b252001-03-05 06:28:06 +0000426 packet_send_ignore(len);
Ben Lindstromaa630de2001-02-10 23:44:47 +0000427 packet_send();
428 }
429 /* Consume the data from the buffer. */
Damien Miller95def091999-11-25 00:26:21 +1100430 buffer_consume(&stdin_buffer, len);
431 /* Update the count of bytes written to the program. */
432 stdin_bytes += len;
433 }
434 }
435 /* Send any buffered packet data to the client. */
436 if (FD_ISSET(connection_out, writeset))
437 packet_write_poll();
438}
439
440/*
441 * Wait until all buffered output has been sent to the client.
442 * This is used when the program terminates.
443 */
Ben Lindstrombba81212001-06-25 05:01:22 +0000444static void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000445drain_output(void)
Damien Miller95def091999-11-25 00:26:21 +1100446{
447 /* Send any buffered stdout data to the client. */
448 if (buffer_len(&stdout_buffer) > 0) {
449 packet_start(SSH_SMSG_STDOUT_DATA);
450 packet_put_string(buffer_ptr(&stdout_buffer),
451 buffer_len(&stdout_buffer));
452 packet_send();
453 /* Update the count of sent bytes. */
454 stdout_bytes += buffer_len(&stdout_buffer);
455 }
456 /* Send any buffered stderr data to the client. */
457 if (buffer_len(&stderr_buffer) > 0) {
458 packet_start(SSH_SMSG_STDERR_DATA);
459 packet_put_string(buffer_ptr(&stderr_buffer),
460 buffer_len(&stderr_buffer));
461 packet_send();
462 /* Update the count of sent bytes. */
463 stderr_bytes += buffer_len(&stderr_buffer);
464 }
465 /* Wait until all buffered data has been written to the client. */
466 packet_write_wait();
467}
468
Ben Lindstrombba81212001-06-25 05:01:22 +0000469static void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000470process_buffered_input_packets(void)
Damien Millerb38eff82000-04-01 11:09:21 +1000471{
Ben Lindstrom8ac91062001-04-04 17:57:54 +0000472 dispatch_run(DISPATCH_NONBLOCK, NULL, compat20 ? xxx_kex : NULL);
Damien Millerb38eff82000-04-01 11:09:21 +1000473}
474
Damien Miller95def091999-11-25 00:26:21 +1100475/*
476 * Performs the interactive session. This handles data transmission between
477 * the client and the program. Note that the notion of stdin, stdout, and
478 * stderr in this function is sort of reversed: this function writes to
479 * stdin (of the child program), and reads from stdout and stderr (of the
480 * child program).
481 */
Damien Miller4af51302000-04-16 11:18:38 +1000482void
Damien Miller166fca82000-04-20 07:42:21 +1000483server_loop(pid_t pid, int fdin_arg, int fdout_arg, int fderr_arg)
Damien Miller95def091999-11-25 00:26:21 +1100484{
Damien Miller5e953212001-01-30 09:14:00 +1100485 fd_set *readset = NULL, *writeset = NULL;
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000486 int max_fd = 0, nalloc = 0;
Damien Miller166fca82000-04-20 07:42:21 +1000487 int wait_status; /* Status returned by wait(). */
488 pid_t wait_pid; /* pid returned by wait(). */
Damien Miller95def091999-11-25 00:26:21 +1100489 int waiting_termination = 0; /* Have displayed waiting close message. */
Ben Lindstrom46c16222000-12-22 01:43:59 +0000490 u_int max_time_milliseconds;
491 u_int previous_stdout_buffer_bytes;
492 u_int stdout_buffer_bytes;
Damien Miller95def091999-11-25 00:26:21 +1100493 int type;
494
495 debug("Entering interactive session.");
496
497 /* Initialize the SIGCHLD kludge. */
Damien Miller95def091999-11-25 00:26:21 +1100498 child_terminated = 0;
Kevin Stevese26a1552001-07-26 17:51:49 +0000499 mysignal(SIGCHLD, sigchld_handler);
Damien Miller95def091999-11-25 00:26:21 +1100500
501 /* Initialize our global variables. */
502 fdin = fdin_arg;
503 fdout = fdout_arg;
504 fderr = fderr_arg;
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000505
506 /* nonblocking IO */
507 set_nonblock(fdin);
508 set_nonblock(fdout);
Damien Miller7d6656c2000-05-20 15:22:36 +1000509 /* we don't have stderr for interactive terminal sessions, see below */
510 if (fderr != -1)
511 set_nonblock(fderr);
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000512
Damien Miller225736c2001-02-19 21:51:08 +1100513 if (!(datafellows & SSH_BUG_IGNOREMSG) && isatty(fdin))
514 fdin_is_tty = 1;
515
Damien Miller95def091999-11-25 00:26:21 +1100516 connection_in = packet_get_connection_in();
517 connection_out = packet_get_connection_out();
518
Damien Millerf6681a32001-12-21 14:53:11 +1100519 notify_setup();
520
Damien Miller95def091999-11-25 00:26:21 +1100521 previous_stdout_buffer_bytes = 0;
522
523 /* Set approximate I/O buffer size. */
524 if (packet_is_interactive())
525 buffer_high = 4096;
526 else
527 buffer_high = 64 * 1024;
528
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000529#if 0
Damien Miller95def091999-11-25 00:26:21 +1100530 /* Initialize max_fd to the maximum of the known file descriptors. */
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000531 max_fd = MAX(connection_in, connection_out);
532 max_fd = MAX(max_fd, fdin);
533 max_fd = MAX(max_fd, fdout);
Damien Miller5e953212001-01-30 09:14:00 +1100534 if (fderr != -1)
535 max_fd = MAX(max_fd, fderr);
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000536#endif
Damien Miller95def091999-11-25 00:26:21 +1100537
538 /* Initialize Initialize buffers. */
539 buffer_init(&stdin_buffer);
540 buffer_init(&stdout_buffer);
541 buffer_init(&stderr_buffer);
542
Damien Miller5428f641999-11-25 11:54:57 +1100543 /*
544 * If we have no separate fderr (which is the case when we have a pty
545 * - there we cannot make difference between data sent to stdout and
546 * stderr), indicate that we have seen an EOF from stderr. This way
547 * we don\'t need to check the descriptor everywhere.
548 */
Damien Miller95def091999-11-25 00:26:21 +1100549 if (fderr == -1)
550 fderr_eof = 1;
551
Damien Millerb38eff82000-04-01 11:09:21 +1000552 server_init_dispatch();
553
Damien Miller95def091999-11-25 00:26:21 +1100554 /* Main loop of the server for the interactive session mode. */
555 for (;;) {
Damien Miller95def091999-11-25 00:26:21 +1100556
557 /* Process buffered packets from the client. */
558 process_buffered_input_packets();
559
Damien Miller5428f641999-11-25 11:54:57 +1100560 /*
561 * If we have received eof, and there is no more pending
562 * input data, cause a real eof by closing fdin.
563 */
Damien Miller95def091999-11-25 00:26:21 +1100564 if (stdin_eof && fdin != -1 && buffer_len(&stdin_buffer) == 0) {
Damien Millerb38eff82000-04-01 11:09:21 +1000565 if (fdin != fdout)
Damien Miller95def091999-11-25 00:26:21 +1100566 close(fdin);
567 else
568 shutdown(fdin, SHUT_WR); /* We will no longer send. */
Damien Miller95def091999-11-25 00:26:21 +1100569 fdin = -1;
570 }
Damien Miller5428f641999-11-25 11:54:57 +1100571 /* Make packets from buffered stderr data to send to the client. */
Damien Miller95def091999-11-25 00:26:21 +1100572 make_packets_from_stderr_data();
573
Damien Miller5428f641999-11-25 11:54:57 +1100574 /*
575 * Make packets from buffered stdout data to send to the
576 * client. If there is very little to send, this arranges to
577 * not send them now, but to wait a short while to see if we
578 * are getting more data. This is necessary, as some systems
579 * wake up readers from a pty after each separate character.
580 */
Damien Miller95def091999-11-25 00:26:21 +1100581 max_time_milliseconds = 0;
582 stdout_buffer_bytes = buffer_len(&stdout_buffer);
583 if (stdout_buffer_bytes != 0 && stdout_buffer_bytes < 256 &&
584 stdout_buffer_bytes != previous_stdout_buffer_bytes) {
585 /* try again after a while */
586 max_time_milliseconds = 10;
587 } else {
588 /* Send it now. */
589 make_packets_from_stdout_data();
590 }
591 previous_stdout_buffer_bytes = buffer_len(&stdout_buffer);
592
593 /* Send channel data to the client. */
594 if (packet_not_very_much_data_to_write())
595 channel_output_poll();
596
Damien Miller5428f641999-11-25 11:54:57 +1100597 /*
598 * Bail out of the loop if the program has closed its output
599 * descriptors, and we have no more data to send to the
600 * client, and there is no pending buffered data.
601 */
Damien Miller43dc8da2000-11-29 15:55:17 +1100602 if (fdout_eof && fderr_eof && !packet_have_data_to_write() &&
603 buffer_len(&stdout_buffer) == 0 && buffer_len(&stderr_buffer) == 0) {
Damien Miller95def091999-11-25 00:26:21 +1100604 if (!channel_still_open())
Damien Millerb38eff82000-04-01 11:09:21 +1000605 break;
Damien Miller95def091999-11-25 00:26:21 +1100606 if (!waiting_termination) {
607 const char *s = "Waiting for forwarded connections to terminate...\r\n";
608 char *cp;
609 waiting_termination = 1;
610 buffer_append(&stderr_buffer, s, strlen(s));
611
612 /* Display list of open channels. */
613 cp = channel_open_message();
614 buffer_append(&stderr_buffer, cp, strlen(cp));
615 xfree(cp);
616 }
617 }
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000618 max_fd = MAX(connection_in, connection_out);
619 max_fd = MAX(max_fd, fdin);
620 max_fd = MAX(max_fd, fdout);
621 max_fd = MAX(max_fd, fderr);
Damien Millerf6681a32001-12-21 14:53:11 +1100622 max_fd = MAX(max_fd, notify_pipe[0]);
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000623
Damien Miller95def091999-11-25 00:26:21 +1100624 /* Sleep in select() until we can do something. */
Damien Miller5e953212001-01-30 09:14:00 +1100625 wait_until_can_do_something(&readset, &writeset, &max_fd,
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000626 &nalloc, max_time_milliseconds);
Damien Miller95def091999-11-25 00:26:21 +1100627
628 /* Process any channel events. */
Damien Miller5e953212001-01-30 09:14:00 +1100629 channel_after_select(readset, writeset);
Damien Miller95def091999-11-25 00:26:21 +1100630
631 /* Process input from the client and from program stdout/stderr. */
Damien Miller5e953212001-01-30 09:14:00 +1100632 process_input(readset);
Damien Miller95def091999-11-25 00:26:21 +1100633
634 /* Process output to the client and to program stdin. */
Damien Miller5e953212001-01-30 09:14:00 +1100635 process_output(writeset);
Damien Miller95def091999-11-25 00:26:21 +1100636 }
Damien Miller5e953212001-01-30 09:14:00 +1100637 if (readset)
638 xfree(readset);
639 if (writeset)
640 xfree(writeset);
Damien Miller95def091999-11-25 00:26:21 +1100641
Damien Miller95def091999-11-25 00:26:21 +1100642 /* Cleanup and termination code. */
643
644 /* Wait until all output has been sent to the client. */
645 drain_output();
646
647 debug("End of interactive session; stdin %ld, stdout (read %ld, sent %ld), stderr %ld bytes.",
Damien Miller9f0f5c62001-12-21 14:45:46 +1100648 stdin_bytes, fdout_bytes, stdout_bytes, stderr_bytes);
Damien Miller95def091999-11-25 00:26:21 +1100649
650 /* Free and clear the buffers. */
651 buffer_free(&stdin_buffer);
652 buffer_free(&stdout_buffer);
653 buffer_free(&stderr_buffer);
654
655 /* Close the file descriptors. */
656 if (fdout != -1)
657 close(fdout);
658 fdout = -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000659 fdout_eof = 1;
Damien Miller95def091999-11-25 00:26:21 +1100660 if (fderr != -1)
661 close(fderr);
662 fderr = -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000663 fderr_eof = 1;
Damien Miller95def091999-11-25 00:26:21 +1100664 if (fdin != -1)
665 close(fdin);
666 fdin = -1;
667
Ben Lindstrom601e4362001-06-21 03:19:23 +0000668 channel_free_all();
Damien Miller95def091999-11-25 00:26:21 +1100669
Damien Miller95def091999-11-25 00:26:21 +1100670 /* We no longer want our SIGCHLD handler to be called. */
Kevin Stevese26a1552001-07-26 17:51:49 +0000671 mysignal(SIGCHLD, SIG_DFL);
Damien Miller95def091999-11-25 00:26:21 +1100672
Ben Lindstrom47fd8112002-04-02 20:48:19 +0000673 while ((wait_pid = waitpid(-1, &wait_status, 0)) < 0)
674 if (errno != EINTR)
675 packet_disconnect("wait: %.100s", strerror(errno));
676 if (wait_pid != pid)
Ben Lindstromce0f6342002-06-11 16:42:49 +0000677 error("Strange, wait returned pid %ld, expected %ld",
678 (long)wait_pid, (long)pid);
Ben Lindstromec46e0b2001-06-09 01:27:31 +0000679
Damien Miller95def091999-11-25 00:26:21 +1100680 /* Check if it exited normally. */
681 if (WIFEXITED(wait_status)) {
682 /* Yes, normal exit. Get exit status and send it to the client. */
683 debug("Command exited with status %d.", WEXITSTATUS(wait_status));
684 packet_start(SSH_SMSG_EXITSTATUS);
685 packet_put_int(WEXITSTATUS(wait_status));
686 packet_send();
687 packet_write_wait();
688
Damien Miller5428f641999-11-25 11:54:57 +1100689 /*
690 * Wait for exit confirmation. Note that there might be
691 * other packets coming before it; however, the program has
692 * already died so we just ignore them. The client is
693 * supposed to respond with the confirmation when it receives
694 * the exit status.
695 */
Damien Miller95def091999-11-25 00:26:21 +1100696 do {
Damien Millerdff50992002-01-22 23:16:32 +1100697 type = packet_read();
Damien Miller95def091999-11-25 00:26:21 +1100698 }
699 while (type != SSH_CMSG_EXIT_CONFIRMATION);
700
701 debug("Received exit confirmation.");
702 return;
703 }
704 /* Check if the program terminated due to a signal. */
705 if (WIFSIGNALED(wait_status))
706 packet_disconnect("Command terminated on signal %d.",
707 WTERMSIG(wait_status));
708
709 /* Some weird exit cause. Just exit. */
710 packet_disconnect("wait returned status %04x.", wait_status);
711 /* NOTREACHED */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000712}
Damien Millerb38eff82000-04-01 11:09:21 +1000713
Damien Miller3ec27592001-10-12 11:35:04 +1000714static void
715collect_children(void)
716{
717 pid_t pid;
718 sigset_t oset, nset;
719 int status;
720
721 /* block SIGCHLD while we check for dead children */
722 sigemptyset(&nset);
723 sigaddset(&nset, SIGCHLD);
724 sigprocmask(SIG_BLOCK, &nset, &oset);
725 if (child_terminated) {
Ben Lindstrom47fd8112002-04-02 20:48:19 +0000726 while ((pid = waitpid(-1, &status, WNOHANG)) > 0 ||
727 (pid < 0 && errno == EINTR))
728 if (pid > 0)
729 session_close_by_pid(pid, status);
Damien Miller3ec27592001-10-12 11:35:04 +1000730 child_terminated = 0;
731 }
732 sigprocmask(SIG_SETMASK, &oset, NULL);
733}
734
Damien Miller4af51302000-04-16 11:18:38 +1000735void
Ben Lindstrombddd5512001-07-04 04:53:53 +0000736server_loop2(Authctxt *authctxt)
Damien Millerefb4afe2000-04-12 18:45:05 +1000737{
Damien Miller5e953212001-01-30 09:14:00 +1100738 fd_set *readset = NULL, *writeset = NULL;
Damien Miller3ec27592001-10-12 11:35:04 +1000739 int rekeying = 0, max_fd, nalloc = 0;
Damien Millerefb4afe2000-04-12 18:45:05 +1000740
741 debug("Entering interactive session for SSH2.");
742
Ben Lindstromec46e0b2001-06-09 01:27:31 +0000743 mysignal(SIGCHLD, sigchld_handler);
Damien Millerefb4afe2000-04-12 18:45:05 +1000744 child_terminated = 0;
745 connection_in = packet_get_connection_in();
746 connection_out = packet_get_connection_out();
Damien Miller5e953212001-01-30 09:14:00 +1100747
Damien Millerf6681a32001-12-21 14:53:11 +1100748 notify_setup();
749
Damien Miller5e953212001-01-30 09:14:00 +1100750 max_fd = MAX(connection_in, connection_out);
Damien Millerf6681a32001-12-21 14:53:11 +1100751 max_fd = MAX(max_fd, notify_pipe[0]);
752
Ben Lindstrombddd5512001-07-04 04:53:53 +0000753 xxx_authctxt = authctxt;
Damien Miller5e953212001-01-30 09:14:00 +1100754
Damien Millerefb4afe2000-04-12 18:45:05 +1000755 server_init_dispatch();
756
757 for (;;) {
758 process_buffered_input_packets();
Ben Lindstrom8e312f32001-04-04 23:50:21 +0000759
Ben Lindstroma3700052001-04-05 23:26:32 +0000760 rekeying = (xxx_kex != NULL && !xxx_kex->done);
Ben Lindstrom8e312f32001-04-04 23:50:21 +0000761
Ben Lindstrom8e312f32001-04-04 23:50:21 +0000762 if (!rekeying && packet_not_very_much_data_to_write())
Damien Millerefb4afe2000-04-12 18:45:05 +1000763 channel_output_poll();
Ben Lindstrom8e312f32001-04-04 23:50:21 +0000764 wait_until_can_do_something(&readset, &writeset, &max_fd,
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000765 &nalloc, 0);
Damien Miller52b77be2001-10-10 15:14:37 +1000766
Damien Miller3ec27592001-10-12 11:35:04 +1000767 collect_children();
Ben Lindstrom8e312f32001-04-04 23:50:21 +0000768 if (!rekeying)
769 channel_after_select(readset, writeset);
Damien Miller5e953212001-01-30 09:14:00 +1100770 process_input(readset);
Ben Lindstrome34ab4c2001-04-07 01:12:11 +0000771 if (connection_closed)
772 break;
Damien Miller5e953212001-01-30 09:14:00 +1100773 process_output(writeset);
Damien Millerefb4afe2000-04-12 18:45:05 +1000774 }
Damien Miller3ec27592001-10-12 11:35:04 +1000775 collect_children();
776
Damien Miller5e953212001-01-30 09:14:00 +1100777 if (readset)
778 xfree(readset);
779 if (writeset)
780 xfree(writeset);
781
Damien Miller52b77be2001-10-10 15:14:37 +1000782 /* free all channels, no more reads and writes */
783 channel_free_all();
Ben Lindstrom4983d5e2001-07-04 05:17:40 +0000784
Damien Miller3ec27592001-10-12 11:35:04 +1000785 /* free remaining sessions, e.g. remove wtmp entries */
Ben Lindstrom7a2073c2002-03-22 02:30:41 +0000786 session_destroy_all(NULL);
Damien Millerefb4afe2000-04-12 18:45:05 +1000787}
788
Ben Lindstrombba81212001-06-25 05:01:22 +0000789static void
Damien Miller630d6f42002-01-22 23:17:30 +1100790server_input_channel_failure(int type, u_int32_t seq, void *ctxt)
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000791{
792 debug("Got CHANNEL_FAILURE for keepalive");
Damien Miller9f0f5c62001-12-21 14:45:46 +1100793 /*
Ben Lindstrom2f0304c2001-04-29 19:49:14 +0000794 * reset timeout, since we got a sane answer from the client.
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000795 * even if this was generated by something other than
796 * the bogus CHANNEL_REQUEST we send for keepalives.
797 */
Damien Miller9f0f5c62001-12-21 14:45:46 +1100798 client_alive_timeouts = 0;
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000799}
800
801
Ben Lindstrombba81212001-06-25 05:01:22 +0000802static void
Damien Miller630d6f42002-01-22 23:17:30 +1100803server_input_stdin_data(int type, u_int32_t seq, void *ctxt)
Damien Millerb38eff82000-04-01 11:09:21 +1000804{
805 char *data;
Ben Lindstrom46c16222000-12-22 01:43:59 +0000806 u_int data_len;
Damien Millerb38eff82000-04-01 11:09:21 +1000807
808 /* Stdin data from the client. Append it to the buffer. */
809 /* Ignore any data if the client has closed stdin. */
810 if (fdin == -1)
811 return;
812 data = packet_get_string(&data_len);
Damien Miller48b03fc2002-01-22 23:11:40 +1100813 packet_check_eom();
Damien Millerb38eff82000-04-01 11:09:21 +1000814 buffer_append(&stdin_buffer, data, data_len);
815 memset(data, 0, data_len);
816 xfree(data);
817}
818
Ben Lindstrombba81212001-06-25 05:01:22 +0000819static void
Damien Miller630d6f42002-01-22 23:17:30 +1100820server_input_eof(int type, u_int32_t seq, void *ctxt)
Damien Millerb38eff82000-04-01 11:09:21 +1000821{
822 /*
823 * Eof from the client. The stdin descriptor to the
824 * program will be closed when all buffered data has
825 * drained.
826 */
827 debug("EOF received for stdin.");
Damien Miller48b03fc2002-01-22 23:11:40 +1100828 packet_check_eom();
Damien Millerb38eff82000-04-01 11:09:21 +1000829 stdin_eof = 1;
830}
831
Ben Lindstrombba81212001-06-25 05:01:22 +0000832static void
Damien Miller630d6f42002-01-22 23:17:30 +1100833server_input_window_size(int type, u_int32_t seq, void *ctxt)
Damien Millerb38eff82000-04-01 11:09:21 +1000834{
835 int row = packet_get_int();
836 int col = packet_get_int();
837 int xpixel = packet_get_int();
838 int ypixel = packet_get_int();
839
840 debug("Window change received.");
Damien Miller48b03fc2002-01-22 23:11:40 +1100841 packet_check_eom();
Damien Millerb38eff82000-04-01 11:09:21 +1000842 if (fdin != -1)
843 pty_change_window_size(fdin, row, col, xpixel, ypixel);
844}
845
Ben Lindstrombba81212001-06-25 05:01:22 +0000846static Channel *
Damien Miller0bc1bd82000-11-13 22:57:25 +1100847server_request_direct_tcpip(char *ctype)
Damien Millerefb4afe2000-04-12 18:45:05 +1000848{
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000849 Channel *c;
850 int sock;
Damien Miller4af51302000-04-16 11:18:38 +1000851 char *target, *originator;
852 int target_port, originator_port;
Damien Millerefb4afe2000-04-12 18:45:05 +1000853
Damien Miller4af51302000-04-16 11:18:38 +1000854 target = packet_get_string(NULL);
855 target_port = packet_get_int();
Damien Millerefb4afe2000-04-12 18:45:05 +1000856 originator = packet_get_string(NULL);
857 originator_port = packet_get_int();
Damien Miller48b03fc2002-01-22 23:11:40 +1100858 packet_check_eom();
Damien Millerb1715dc2000-05-30 13:44:51 +1000859
Damien Miller0bc1bd82000-11-13 22:57:25 +1100860 debug("server_request_direct_tcpip: originator %s port %d, target %s port %d",
Damien Millerb1715dc2000-05-30 13:44:51 +1000861 originator, originator_port, target, target_port);
Damien Millerf6d9e222000-06-18 14:50:44 +1000862
Damien Millerefb4afe2000-04-12 18:45:05 +1000863 /* XXX check permission */
Damien Miller4af51302000-04-16 11:18:38 +1000864 sock = channel_connect_to(target, target_port);
865 xfree(target);
Damien Millerefb4afe2000-04-12 18:45:05 +1000866 xfree(originator);
867 if (sock < 0)
Damien Miller0bc1bd82000-11-13 22:57:25 +1100868 return NULL;
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000869 c = channel_new(ctype, SSH_CHANNEL_CONNECTING,
Damien Millere4340be2000-09-16 13:29:08 +1100870 sock, sock, -1, CHAN_TCP_WINDOW_DEFAULT,
Damien Miller69b69aa2000-10-28 14:19:58 +1100871 CHAN_TCP_PACKET_DEFAULT, 0, xstrdup("direct-tcpip"), 1);
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000872 return c;
Damien Miller0bc1bd82000-11-13 22:57:25 +1100873}
874
Ben Lindstrombba81212001-06-25 05:01:22 +0000875static Channel *
Damien Miller0bc1bd82000-11-13 22:57:25 +1100876server_request_session(char *ctype)
877{
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000878 Channel *c;
Damien Miller0bc1bd82000-11-13 22:57:25 +1100879
880 debug("input_session_request");
Damien Miller48b03fc2002-01-22 23:11:40 +1100881 packet_check_eom();
Damien Miller0bc1bd82000-11-13 22:57:25 +1100882 /*
883 * A server session has no fd to read or write until a
884 * CHANNEL_REQUEST for a shell is made, so we set the type to
885 * SSH_CHANNEL_LARVAL. Additionally, a callback for handling all
886 * CHANNEL_REQUEST messages is registered.
887 */
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000888 c = channel_new(ctype, SSH_CHANNEL_LARVAL,
889 -1, -1, -1, /*window size*/0, CHAN_SES_PACKET_DEFAULT,
Damien Miller0bc1bd82000-11-13 22:57:25 +1100890 0, xstrdup("server-session"), 1);
Ben Lindstrombddd5512001-07-04 04:53:53 +0000891 if (session_open(xxx_authctxt, c->self) != 1) {
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000892 debug("session open failed, free channel %d", c->self);
893 channel_free(c);
894 return NULL;
895 }
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000896 channel_register_cleanup(c->self, session_close_by_channel);
897 return c;
Damien Millerefb4afe2000-04-12 18:45:05 +1000898}
899
Ben Lindstrombba81212001-06-25 05:01:22 +0000900static void
Damien Miller630d6f42002-01-22 23:17:30 +1100901server_input_channel_open(int type, u_int32_t seq, void *ctxt)
Damien Millerefb4afe2000-04-12 18:45:05 +1000902{
903 Channel *c = NULL;
904 char *ctype;
Damien Millerefb4afe2000-04-12 18:45:05 +1000905 int rchan;
Ben Lindstrom4fed2be2002-06-25 23:17:36 +0000906 u_int rmaxpack, rwindow, len;
Damien Millerefb4afe2000-04-12 18:45:05 +1000907
908 ctype = packet_get_string(&len);
909 rchan = packet_get_int();
910 rwindow = packet_get_int();
911 rmaxpack = packet_get_int();
912
Damien Miller62cee002000-09-23 17:15:56 +1100913 debug("server_input_channel_open: ctype %s rchan %d win %d max %d",
Damien Millerefb4afe2000-04-12 18:45:05 +1000914 ctype, rchan, rwindow, rmaxpack);
915
916 if (strcmp(ctype, "session") == 0) {
Damien Miller0bc1bd82000-11-13 22:57:25 +1100917 c = server_request_session(ctype);
Damien Millerefb4afe2000-04-12 18:45:05 +1000918 } else if (strcmp(ctype, "direct-tcpip") == 0) {
Damien Miller0bc1bd82000-11-13 22:57:25 +1100919 c = server_request_direct_tcpip(ctype);
Damien Millerefb4afe2000-04-12 18:45:05 +1000920 }
921 if (c != NULL) {
Damien Miller0bc1bd82000-11-13 22:57:25 +1100922 debug("server_input_channel_open: confirm %s", ctype);
Damien Millerefb4afe2000-04-12 18:45:05 +1000923 c->remote_id = rchan;
924 c->remote_window = rwindow;
925 c->remote_maxpacket = rmaxpack;
Ben Lindstrom69128662001-05-08 20:07:39 +0000926 if (c->type != SSH_CHANNEL_CONNECTING) {
927 packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
928 packet_put_int(c->remote_id);
929 packet_put_int(c->self);
930 packet_put_int(c->local_window);
931 packet_put_int(c->local_maxpacket);
932 packet_send();
933 }
Damien Millerefb4afe2000-04-12 18:45:05 +1000934 } else {
Damien Miller0bc1bd82000-11-13 22:57:25 +1100935 debug("server_input_channel_open: failure %s", ctype);
Damien Millerefb4afe2000-04-12 18:45:05 +1000936 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
937 packet_put_int(rchan);
938 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
Ben Lindstromf3436742001-04-29 19:52:00 +0000939 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
Ben Lindstrom69128662001-05-08 20:07:39 +0000940 packet_put_cstring("open failed");
Ben Lindstromf3436742001-04-29 19:52:00 +0000941 packet_put_cstring("");
942 }
Damien Millerefb4afe2000-04-12 18:45:05 +1000943 packet_send();
944 }
945 xfree(ctype);
946}
947
Ben Lindstrombba81212001-06-25 05:01:22 +0000948static void
Damien Miller630d6f42002-01-22 23:17:30 +1100949server_input_global_request(int type, u_int32_t seq, void *ctxt)
Damien Miller0bc1bd82000-11-13 22:57:25 +1100950{
951 char *rtype;
952 int want_reply;
953 int success = 0;
954
955 rtype = packet_get_string(NULL);
956 want_reply = packet_get_char();
957 debug("server_input_global_request: rtype %s want_reply %d", rtype, want_reply);
Kevin Stevesef4eea92001-02-05 12:42:17 +0000958
Ben Lindstrom7bb8b492001-03-17 00:47:54 +0000959 /* -R style forwarding */
Damien Miller0bc1bd82000-11-13 22:57:25 +1100960 if (strcmp(rtype, "tcpip-forward") == 0) {
961 struct passwd *pw;
962 char *listen_address;
963 u_short listen_port;
964
965 pw = auth_get_user();
966 if (pw == NULL)
967 fatal("server_input_global_request: no user");
968 listen_address = packet_get_string(NULL); /* XXX currently ignored */
969 listen_port = (u_short)packet_get_int();
970 debug("server_input_global_request: tcpip-forward listen %s port %d",
971 listen_address, listen_port);
972
973 /* check permissions */
974 if (!options.allow_tcp_forwarding ||
Ben Lindstrom99a4e142002-07-09 14:06:40 +0000975 no_port_forwarding_flag
976#ifndef NO_IPPORT_RESERVED_CONCEPT
977 || (listen_port < IPPORT_RESERVED && pw->pw_uid != 0)
978#endif
979 ) {
Damien Miller0bc1bd82000-11-13 22:57:25 +1100980 success = 0;
981 packet_send_debug("Server has disabled port forwarding.");
982 } else {
983 /* Start listening on the port */
Damien Millerb16461c2002-01-22 23:29:22 +1100984 success = channel_setup_remote_fwd_listener(
985 listen_address, listen_port, options.gateway_ports);
Damien Miller0bc1bd82000-11-13 22:57:25 +1100986 }
987 xfree(listen_address);
988 }
989 if (want_reply) {
990 packet_start(success ?
991 SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
992 packet_send();
993 packet_write_wait();
994 }
995 xfree(rtype);
996}
Damien Millerc7ef63d2002-02-05 12:21:42 +1100997static void
998server_input_channel_req(int type, u_int32_t seq, void *ctxt)
999{
1000 Channel *c;
1001 int id, reply, success = 0;
1002 char *rtype;
1003
1004 id = packet_get_int();
1005 rtype = packet_get_string(NULL);
1006 reply = packet_get_char();
1007
1008 debug("server_input_channel_req: channel %d request %s reply %d",
1009 id, rtype, reply);
1010
1011 if ((c = channel_lookup(id)) == NULL)
1012 packet_disconnect("server_input_channel_req: "
1013 "unknown channel %d", id);
1014 if (c->type == SSH_CHANNEL_LARVAL || c->type == SSH_CHANNEL_OPEN)
1015 success = session_input_channel_req(c, rtype);
1016 if (reply) {
1017 packet_start(success ?
1018 SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1019 packet_put_int(c->remote_id);
1020 packet_send();
1021 }
1022 xfree(rtype);
1023}
Damien Miller0bc1bd82000-11-13 22:57:25 +11001024
Ben Lindstrombba81212001-06-25 05:01:22 +00001025static void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +00001026server_init_dispatch_20(void)
Damien Millerefb4afe2000-04-12 18:45:05 +10001027{
1028 debug("server_init_dispatch_20");
1029 dispatch_init(&dispatch_protocol_error);
1030 dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
1031 dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
1032 dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
1033 dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
1034 dispatch_set(SSH2_MSG_CHANNEL_OPEN, &server_input_channel_open);
1035 dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1036 dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
Damien Millerc7ef63d2002-02-05 12:21:42 +11001037 dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &server_input_channel_req);
Damien Millerefb4afe2000-04-12 18:45:05 +10001038 dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
Damien Miller0bc1bd82000-11-13 22:57:25 +11001039 dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &server_input_global_request);
Ben Lindstrom5744dc42001-04-13 23:28:01 +00001040 /* client_alive */
1041 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &server_input_channel_failure);
Ben Lindstrom8ac91062001-04-04 17:57:54 +00001042 /* rekeying */
1043 dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
Damien Millerefb4afe2000-04-12 18:45:05 +10001044}
Ben Lindstrombba81212001-06-25 05:01:22 +00001045static void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +00001046server_init_dispatch_13(void)
Damien Millerb38eff82000-04-01 11:09:21 +10001047{
1048 debug("server_init_dispatch_13");
1049 dispatch_init(NULL);
1050 dispatch_set(SSH_CMSG_EOF, &server_input_eof);
1051 dispatch_set(SSH_CMSG_STDIN_DATA, &server_input_stdin_data);
1052 dispatch_set(SSH_CMSG_WINDOW_SIZE, &server_input_window_size);
1053 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
1054 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
1055 dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
1056 dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1057 dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1058 dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
1059}
Ben Lindstrombba81212001-06-25 05:01:22 +00001060static void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +00001061server_init_dispatch_15(void)
Damien Millerb38eff82000-04-01 11:09:21 +10001062{
1063 server_init_dispatch_13();
1064 debug("server_init_dispatch_15");
1065 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
1066 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_oclose);
1067}
Ben Lindstrombba81212001-06-25 05:01:22 +00001068static void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +00001069server_init_dispatch(void)
Damien Millerb38eff82000-04-01 11:09:21 +10001070{
Damien Millerefb4afe2000-04-12 18:45:05 +10001071 if (compat20)
1072 server_init_dispatch_20();
1073 else if (compat13)
Damien Millerb38eff82000-04-01 11:09:21 +10001074 server_init_dispatch_13();
1075 else
1076 server_init_dispatch_15();
1077}