blob: 0b44182ce3c1c4de4223d66c8aec8d023339f599 [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 Lindstrom16d29d52001-07-18 16:01:46 +000038RCSID("$OpenBSD: serverloop.c,v 1.76 2001/07/17 21:04:58 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 Millerd4a8b7e1999-10-27 13:42:43 +100083
Damien Miller5428f641999-11-25 11:54:57 +110084/*
85 * This SIGCHLD kludge is used to detect when the child exits. The server
86 * will exit after that, as soon as forwarded connections have terminated.
87 */
Ben Lindstrombba81212001-06-25 05:01:22 +000088
Damien Millerd4a8b7e1999-10-27 13:42:43 +100089static volatile int child_terminated; /* The child has terminated. */
Damien Millerd4a8b7e1999-10-27 13:42:43 +100090
Ben Lindstrombba81212001-06-25 05:01:22 +000091/* prototypes */
92static void server_init_dispatch(void);
Damien Millerb38eff82000-04-01 11:09:21 +100093
Ben Lindstrom5744dc42001-04-13 23:28:01 +000094int client_alive_timeouts = 0;
95
Ben Lindstrombba81212001-06-25 05:01:22 +000096static void
Damien Miller95def091999-11-25 00:26:21 +110097sigchld_handler(int sig)
Damien Millerd4a8b7e1999-10-27 13:42:43 +100098{
Damien Miller95def091999-11-25 00:26:21 +110099 int save_errno = errno;
Damien Millerefb4afe2000-04-12 18:45:05 +1000100 debug("Received SIGCHLD.");
101 child_terminated = 1;
Ben Lindstromec46e0b2001-06-09 01:27:31 +0000102 mysignal(SIGCHLD, sigchld_handler);
Damien Millerefb4afe2000-04-12 18:45:05 +1000103 errno = save_errno;
104}
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000105
Damien Miller95def091999-11-25 00:26:21 +1100106/*
Damien Miller95def091999-11-25 00:26:21 +1100107 * Make packets from buffered stderr data, and buffer it for sending
108 * to the client.
109 */
Ben Lindstrombba81212001-06-25 05:01:22 +0000110static void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000111make_packets_from_stderr_data(void)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000112{
Damien Miller95def091999-11-25 00:26:21 +1100113 int len;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000114
Damien Miller95def091999-11-25 00:26:21 +1100115 /* Send buffered stderr data to the client. */
116 while (buffer_len(&stderr_buffer) > 0 &&
Damien Miller037a0dc1999-12-07 15:38:31 +1100117 packet_not_very_much_data_to_write()) {
Damien Miller95def091999-11-25 00:26:21 +1100118 len = buffer_len(&stderr_buffer);
119 if (packet_is_interactive()) {
120 if (len > 512)
121 len = 512;
122 } else {
123 /* Keep the packets at reasonable size. */
124 if (len > packet_get_maxsize())
125 len = packet_get_maxsize();
126 }
127 packet_start(SSH_SMSG_STDERR_DATA);
128 packet_put_string(buffer_ptr(&stderr_buffer), len);
129 packet_send();
130 buffer_consume(&stderr_buffer, len);
131 stderr_bytes += len;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000132 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000133}
134
Damien Miller95def091999-11-25 00:26:21 +1100135/*
136 * Make packets from buffered stdout data, and buffer it for sending to the
137 * client.
138 */
Ben Lindstrombba81212001-06-25 05:01:22 +0000139static void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000140make_packets_from_stdout_data(void)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000141{
Damien Miller95def091999-11-25 00:26:21 +1100142 int len;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000143
Damien Miller95def091999-11-25 00:26:21 +1100144 /* Send buffered stdout data to the client. */
145 while (buffer_len(&stdout_buffer) > 0 &&
Damien Miller037a0dc1999-12-07 15:38:31 +1100146 packet_not_very_much_data_to_write()) {
Damien Miller95def091999-11-25 00:26:21 +1100147 len = buffer_len(&stdout_buffer);
148 if (packet_is_interactive()) {
149 if (len > 512)
150 len = 512;
151 } else {
152 /* Keep the packets at reasonable size. */
153 if (len > packet_get_maxsize())
Kevin Stevesef4eea92001-02-05 12:42:17 +0000154 len = packet_get_maxsize();
Damien Miller95def091999-11-25 00:26:21 +1100155 }
156 packet_start(SSH_SMSG_STDOUT_DATA);
157 packet_put_string(buffer_ptr(&stdout_buffer), len);
158 packet_send();
159 buffer_consume(&stdout_buffer, len);
160 stdout_bytes += len;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000161 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000162}
163
Damien Miller95def091999-11-25 00:26:21 +1100164/*
165 * Sleep in select() until we can do something. This will initialize the
166 * select masks. Upon return, the masks will indicate which descriptors
167 * have data or can accept data. Optionally, a maximum time can be specified
168 * for the duration of the wait (0 = infinite).
169 */
Ben Lindstrombba81212001-06-25 05:01:22 +0000170static void
Damien Miller5e953212001-01-30 09:14:00 +1100171wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000172 int *nallocp, u_int max_time_milliseconds)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000173{
Damien Miller95def091999-11-25 00:26:21 +1100174 struct timeval tv, *tvp;
175 int ret;
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000176 int client_alive_scheduled = 0;
177
178 /*
179 * if using client_alive, set the max timeout accordingly,
180 * and indicate that this particular timeout was for client
181 * alive by setting the client_alive_scheduled flag.
182 *
183 * this could be randomized somewhat to make traffic
184 * analysis more difficult, but we're not doing it yet.
185 */
Ben Lindstrom36857f62001-07-18 15:48:57 +0000186 if (compat20 &&
187 max_time_milliseconds == 0 && options.client_alive_interval) {
Ben Lindstrom2f0304c2001-04-29 19:49:14 +0000188 client_alive_scheduled = 1;
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000189 max_time_milliseconds = options.client_alive_interval * 1000;
Ben Lindstrom36857f62001-07-18 15:48:57 +0000190 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000191
Damien Miller95def091999-11-25 00:26:21 +1100192 /* When select fails we restart from here. */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000193retry_select:
194
Damien Miller5e953212001-01-30 09:14:00 +1100195 /* Allocate and update select() masks for channel descriptors. */
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000196 channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, 0);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000197
Damien Millerefb4afe2000-04-12 18:45:05 +1000198 if (compat20) {
Damien Millere247cc42000-05-07 12:03:14 +1000199 /* wrong: bad condition XXX */
Damien Millerefb4afe2000-04-12 18:45:05 +1000200 if (channel_not_very_much_buffered_data())
Damien Miller5e953212001-01-30 09:14:00 +1100201 FD_SET(connection_in, *readsetp);
Damien Millerefb4afe2000-04-12 18:45:05 +1000202 } else {
Damien Millerb1715dc2000-05-30 13:44:51 +1000203 /*
204 * Read packets from the client unless we have too much
205 * buffered stdin or channel data.
206 */
207 if (buffer_len(&stdin_buffer) < buffer_high &&
Damien Millerefb4afe2000-04-12 18:45:05 +1000208 channel_not_very_much_buffered_data())
Damien Miller5e953212001-01-30 09:14:00 +1100209 FD_SET(connection_in, *readsetp);
Damien Millerb1715dc2000-05-30 13:44:51 +1000210 /*
211 * If there is not too much data already buffered going to
212 * the client, try to get some more data from the program.
213 */
214 if (packet_not_very_much_data_to_write()) {
215 if (!fdout_eof)
Damien Miller5e953212001-01-30 09:14:00 +1100216 FD_SET(fdout, *readsetp);
Damien Millerb1715dc2000-05-30 13:44:51 +1000217 if (!fderr_eof)
Damien Miller5e953212001-01-30 09:14:00 +1100218 FD_SET(fderr, *readsetp);
Damien Millerb1715dc2000-05-30 13:44:51 +1000219 }
220 /*
221 * If we have buffered data, try to write some of that data
222 * to the program.
223 */
224 if (fdin != -1 && buffer_len(&stdin_buffer) > 0)
Damien Miller5e953212001-01-30 09:14:00 +1100225 FD_SET(fdin, *writesetp);
Damien Millerefb4afe2000-04-12 18:45:05 +1000226 }
Damien Miller95def091999-11-25 00:26:21 +1100227
Damien Miller5428f641999-11-25 11:54:57 +1100228 /*
229 * If we have buffered packet data going to the client, mark that
230 * descriptor.
231 */
Damien Miller95def091999-11-25 00:26:21 +1100232 if (packet_have_data_to_write())
Damien Miller5e953212001-01-30 09:14:00 +1100233 FD_SET(connection_out, *writesetp);
Damien Miller95def091999-11-25 00:26:21 +1100234
Damien Miller5428f641999-11-25 11:54:57 +1100235 /*
236 * If child has terminated and there is enough buffer space to read
237 * from it, then read as much as is available and exit.
238 */
Damien Miller95def091999-11-25 00:26:21 +1100239 if (child_terminated && packet_not_very_much_data_to_write())
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000240 if (max_time_milliseconds == 0 || client_alive_scheduled)
Damien Miller95def091999-11-25 00:26:21 +1100241 max_time_milliseconds = 100;
242
243 if (max_time_milliseconds == 0)
244 tvp = NULL;
245 else {
246 tv.tv_sec = max_time_milliseconds / 1000;
247 tv.tv_usec = 1000 * (max_time_milliseconds % 1000);
248 tvp = &tv;
249 }
Damien Millerefb4afe2000-04-12 18:45:05 +1000250 if (tvp!=NULL)
Ben Lindstromf4c73112001-03-05 05:58:23 +0000251 debug3("tvp!=NULL kid %d mili %d", child_terminated, max_time_milliseconds);
Damien Miller95def091999-11-25 00:26:21 +1100252
253 /* Wait for something to happen, or the timeout to expire. */
Damien Miller5e953212001-01-30 09:14:00 +1100254 ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
Damien Miller95def091999-11-25 00:26:21 +1100255
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000256 if (ret == -1) {
Damien Miller95def091999-11-25 00:26:21 +1100257 if (errno != EINTR)
258 error("select: %.100s", strerror(errno));
259 else
260 goto retry_select;
261 }
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000262 if (ret == 0 && client_alive_scheduled) {
263 /* timeout, check to see how many we have had */
264 client_alive_timeouts++;
265
266 if (client_alive_timeouts > options.client_alive_count_max ) {
267 packet_disconnect(
268 "Timeout, your session not responding.");
269 } else {
270 /*
271 * send a bogus channel request with "wantreply"
272 * we should get back a failure
273 */
274 int id;
275
276 id = channel_find_open();
277 if (id != -1) {
278 channel_request_start(id,
279 "keepalive@openssh.com", 1);
280 packet_send();
281 } else
282 packet_disconnect(
283 "No open channels after timeout!");
284 }
285 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000286}
287
Damien Miller95def091999-11-25 00:26:21 +1100288/*
289 * Processes input from the client and the program. Input data is stored
290 * in buffers and processed later.
291 */
Ben Lindstrombba81212001-06-25 05:01:22 +0000292static void
Damien Miller95def091999-11-25 00:26:21 +1100293process_input(fd_set * readset)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000294{
Damien Miller95def091999-11-25 00:26:21 +1100295 int len;
296 char buf[16384];
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000297
Damien Miller95def091999-11-25 00:26:21 +1100298 /* Read and buffer any input data from the client. */
299 if (FD_ISSET(connection_in, readset)) {
300 len = read(connection_in, buf, sizeof(buf));
301 if (len == 0) {
302 verbose("Connection closed by remote host.");
Ben Lindstrome34ab4c2001-04-07 01:12:11 +0000303 connection_closed = 1;
304 if (compat20)
305 return;
Damien Miller95def091999-11-25 00:26:21 +1100306 fatal_cleanup();
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000307 } else if (len < 0) {
308 if (errno != EINTR && errno != EAGAIN) {
309 verbose("Read error from remote host: %.100s", strerror(errno));
310 fatal_cleanup();
311 }
312 } else {
313 /* Buffer any received data. */
314 packet_process_incoming(buf, len);
Damien Miller95def091999-11-25 00:26:21 +1100315 }
Damien Miller95def091999-11-25 00:26:21 +1100316 }
Damien Millerefb4afe2000-04-12 18:45:05 +1000317 if (compat20)
318 return;
319
Damien Miller95def091999-11-25 00:26:21 +1100320 /* Read and buffer any available stdout data from the program. */
321 if (!fdout_eof && FD_ISSET(fdout, readset)) {
322 len = read(fdout, buf, sizeof(buf));
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000323 if (len < 0 && (errno == EINTR || errno == EAGAIN)) {
324 /* do nothing */
325 } else if (len <= 0) {
Damien Miller95def091999-11-25 00:26:21 +1100326 fdout_eof = 1;
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000327 } else {
Damien Miller95def091999-11-25 00:26:21 +1100328 buffer_append(&stdout_buffer, buf, len);
329 fdout_bytes += len;
330 }
331 }
332 /* Read and buffer any available stderr data from the program. */
333 if (!fderr_eof && FD_ISSET(fderr, readset)) {
334 len = read(fderr, buf, sizeof(buf));
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000335 if (len < 0 && (errno == EINTR || errno == EAGAIN)) {
336 /* do nothing */
337 } else if (len <= 0) {
Damien Miller95def091999-11-25 00:26:21 +1100338 fderr_eof = 1;
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000339 } else {
Damien Miller95def091999-11-25 00:26:21 +1100340 buffer_append(&stderr_buffer, buf, len);
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000341 }
Damien Miller95def091999-11-25 00:26:21 +1100342 }
343}
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000344
Damien Miller95def091999-11-25 00:26:21 +1100345/*
346 * Sends data from internal buffers to client program stdin.
347 */
Ben Lindstrombba81212001-06-25 05:01:22 +0000348static void
Damien Miller95def091999-11-25 00:26:21 +1100349process_output(fd_set * writeset)
350{
Ben Lindstromaa630de2001-02-10 23:44:47 +0000351 struct termios tio;
Damien Miller95def091999-11-25 00:26:21 +1100352 int len;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000353
Damien Miller95def091999-11-25 00:26:21 +1100354 /* Write buffered data to program stdin. */
Damien Millerefb4afe2000-04-12 18:45:05 +1000355 if (!compat20 && fdin != -1 && FD_ISSET(fdin, writeset)) {
Damien Miller95def091999-11-25 00:26:21 +1100356 len = write(fdin, buffer_ptr(&stdin_buffer),
Damien Miller037a0dc1999-12-07 15:38:31 +1100357 buffer_len(&stdin_buffer));
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000358 if (len < 0 && (errno == EINTR || errno == EAGAIN)) {
359 /* do nothing */
360 } else if (len <= 0) {
Damien Miller95def091999-11-25 00:26:21 +1100361#ifdef USE_PIPES
362 close(fdin);
363#else
Damien Millerb38eff82000-04-01 11:09:21 +1000364 if (fdin != fdout)
Damien Miller95def091999-11-25 00:26:21 +1100365 close(fdin);
366 else
367 shutdown(fdin, SHUT_WR); /* We will no longer send. */
368#endif
369 fdin = -1;
370 } else {
Ben Lindstromaa630de2001-02-10 23:44:47 +0000371 /* Successful write. */
Damien Miller225736c2001-02-19 21:51:08 +1100372 if (fdin_is_tty && tcgetattr(fdin, &tio) == 0 &&
Damien Miller79438cc2001-02-16 12:34:57 +1100373 !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
Kevin Stevesb7f036f2001-02-15 17:27:15 +0000374 /*
375 * Simulate echo to reduce the impact of
376 * traffic analysis
377 */
Ben Lindstrome229b252001-03-05 06:28:06 +0000378 packet_send_ignore(len);
Ben Lindstromaa630de2001-02-10 23:44:47 +0000379 packet_send();
380 }
381 /* Consume the data from the buffer. */
Damien Miller95def091999-11-25 00:26:21 +1100382 buffer_consume(&stdin_buffer, len);
383 /* Update the count of bytes written to the program. */
384 stdin_bytes += len;
385 }
386 }
387 /* Send any buffered packet data to the client. */
388 if (FD_ISSET(connection_out, writeset))
389 packet_write_poll();
390}
391
392/*
393 * Wait until all buffered output has been sent to the client.
394 * This is used when the program terminates.
395 */
Ben Lindstrombba81212001-06-25 05:01:22 +0000396static void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000397drain_output(void)
Damien Miller95def091999-11-25 00:26:21 +1100398{
399 /* Send any buffered stdout data to the client. */
400 if (buffer_len(&stdout_buffer) > 0) {
401 packet_start(SSH_SMSG_STDOUT_DATA);
402 packet_put_string(buffer_ptr(&stdout_buffer),
403 buffer_len(&stdout_buffer));
404 packet_send();
405 /* Update the count of sent bytes. */
406 stdout_bytes += buffer_len(&stdout_buffer);
407 }
408 /* Send any buffered stderr data to the client. */
409 if (buffer_len(&stderr_buffer) > 0) {
410 packet_start(SSH_SMSG_STDERR_DATA);
411 packet_put_string(buffer_ptr(&stderr_buffer),
412 buffer_len(&stderr_buffer));
413 packet_send();
414 /* Update the count of sent bytes. */
415 stderr_bytes += buffer_len(&stderr_buffer);
416 }
417 /* Wait until all buffered data has been written to the client. */
418 packet_write_wait();
419}
420
Ben Lindstrombba81212001-06-25 05:01:22 +0000421static void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000422process_buffered_input_packets(void)
Damien Millerb38eff82000-04-01 11:09:21 +1000423{
Ben Lindstrom8ac91062001-04-04 17:57:54 +0000424 dispatch_run(DISPATCH_NONBLOCK, NULL, compat20 ? xxx_kex : NULL);
Damien Millerb38eff82000-04-01 11:09:21 +1000425}
426
Damien Miller95def091999-11-25 00:26:21 +1100427/*
428 * Performs the interactive session. This handles data transmission between
429 * the client and the program. Note that the notion of stdin, stdout, and
430 * stderr in this function is sort of reversed: this function writes to
431 * stdin (of the child program), and reads from stdout and stderr (of the
432 * child program).
433 */
Damien Miller4af51302000-04-16 11:18:38 +1000434void
Damien Miller166fca82000-04-20 07:42:21 +1000435server_loop(pid_t pid, int fdin_arg, int fdout_arg, int fderr_arg)
Damien Miller95def091999-11-25 00:26:21 +1100436{
Damien Miller5e953212001-01-30 09:14:00 +1100437 fd_set *readset = NULL, *writeset = NULL;
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000438 int max_fd = 0, nalloc = 0;
Damien Miller166fca82000-04-20 07:42:21 +1000439 int wait_status; /* Status returned by wait(). */
440 pid_t wait_pid; /* pid returned by wait(). */
Damien Miller95def091999-11-25 00:26:21 +1100441 int waiting_termination = 0; /* Have displayed waiting close message. */
Ben Lindstrom46c16222000-12-22 01:43:59 +0000442 u_int max_time_milliseconds;
443 u_int previous_stdout_buffer_bytes;
444 u_int stdout_buffer_bytes;
Damien Miller95def091999-11-25 00:26:21 +1100445 int type;
446
447 debug("Entering interactive session.");
448
449 /* Initialize the SIGCHLD kludge. */
Damien Miller95def091999-11-25 00:26:21 +1100450 child_terminated = 0;
Kevin Stevese26a1552001-07-26 17:51:49 +0000451 mysignal(SIGCHLD, sigchld_handler);
Damien Miller95def091999-11-25 00:26:21 +1100452
453 /* Initialize our global variables. */
454 fdin = fdin_arg;
455 fdout = fdout_arg;
456 fderr = fderr_arg;
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000457
458 /* nonblocking IO */
459 set_nonblock(fdin);
460 set_nonblock(fdout);
Damien Miller7d6656c2000-05-20 15:22:36 +1000461 /* we don't have stderr for interactive terminal sessions, see below */
462 if (fderr != -1)
463 set_nonblock(fderr);
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000464
Damien Miller225736c2001-02-19 21:51:08 +1100465 if (!(datafellows & SSH_BUG_IGNOREMSG) && isatty(fdin))
466 fdin_is_tty = 1;
467
Damien Miller95def091999-11-25 00:26:21 +1100468 connection_in = packet_get_connection_in();
469 connection_out = packet_get_connection_out();
470
471 previous_stdout_buffer_bytes = 0;
472
473 /* Set approximate I/O buffer size. */
474 if (packet_is_interactive())
475 buffer_high = 4096;
476 else
477 buffer_high = 64 * 1024;
478
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000479#if 0
Damien Miller95def091999-11-25 00:26:21 +1100480 /* Initialize max_fd to the maximum of the known file descriptors. */
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000481 max_fd = MAX(connection_in, connection_out);
482 max_fd = MAX(max_fd, fdin);
483 max_fd = MAX(max_fd, fdout);
Damien Miller5e953212001-01-30 09:14:00 +1100484 if (fderr != -1)
485 max_fd = MAX(max_fd, fderr);
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000486#endif
Damien Miller95def091999-11-25 00:26:21 +1100487
488 /* Initialize Initialize buffers. */
489 buffer_init(&stdin_buffer);
490 buffer_init(&stdout_buffer);
491 buffer_init(&stderr_buffer);
492
Damien Miller5428f641999-11-25 11:54:57 +1100493 /*
494 * If we have no separate fderr (which is the case when we have a pty
495 * - there we cannot make difference between data sent to stdout and
496 * stderr), indicate that we have seen an EOF from stderr. This way
497 * we don\'t need to check the descriptor everywhere.
498 */
Damien Miller95def091999-11-25 00:26:21 +1100499 if (fderr == -1)
500 fderr_eof = 1;
501
Damien Millerb38eff82000-04-01 11:09:21 +1000502 server_init_dispatch();
503
Damien Miller95def091999-11-25 00:26:21 +1100504 /* Main loop of the server for the interactive session mode. */
505 for (;;) {
Damien Miller95def091999-11-25 00:26:21 +1100506
507 /* Process buffered packets from the client. */
508 process_buffered_input_packets();
509
Damien Miller5428f641999-11-25 11:54:57 +1100510 /*
511 * If we have received eof, and there is no more pending
512 * input data, cause a real eof by closing fdin.
513 */
Damien Miller95def091999-11-25 00:26:21 +1100514 if (stdin_eof && fdin != -1 && buffer_len(&stdin_buffer) == 0) {
515#ifdef USE_PIPES
516 close(fdin);
517#else
Damien Millerb38eff82000-04-01 11:09:21 +1000518 if (fdin != fdout)
Damien Miller95def091999-11-25 00:26:21 +1100519 close(fdin);
520 else
521 shutdown(fdin, SHUT_WR); /* We will no longer send. */
522#endif
523 fdin = -1;
524 }
Damien Miller5428f641999-11-25 11:54:57 +1100525 /* Make packets from buffered stderr data to send to the client. */
Damien Miller95def091999-11-25 00:26:21 +1100526 make_packets_from_stderr_data();
527
Damien Miller5428f641999-11-25 11:54:57 +1100528 /*
529 * Make packets from buffered stdout data to send to the
530 * client. If there is very little to send, this arranges to
531 * not send them now, but to wait a short while to see if we
532 * are getting more data. This is necessary, as some systems
533 * wake up readers from a pty after each separate character.
534 */
Damien Miller95def091999-11-25 00:26:21 +1100535 max_time_milliseconds = 0;
536 stdout_buffer_bytes = buffer_len(&stdout_buffer);
537 if (stdout_buffer_bytes != 0 && stdout_buffer_bytes < 256 &&
538 stdout_buffer_bytes != previous_stdout_buffer_bytes) {
539 /* try again after a while */
540 max_time_milliseconds = 10;
541 } else {
542 /* Send it now. */
543 make_packets_from_stdout_data();
544 }
545 previous_stdout_buffer_bytes = buffer_len(&stdout_buffer);
546
547 /* Send channel data to the client. */
548 if (packet_not_very_much_data_to_write())
549 channel_output_poll();
550
Damien Miller5428f641999-11-25 11:54:57 +1100551 /*
552 * Bail out of the loop if the program has closed its output
553 * descriptors, and we have no more data to send to the
554 * client, and there is no pending buffered data.
555 */
Damien Miller43dc8da2000-11-29 15:55:17 +1100556 if (fdout_eof && fderr_eof && !packet_have_data_to_write() &&
557 buffer_len(&stdout_buffer) == 0 && buffer_len(&stderr_buffer) == 0) {
Damien Miller95def091999-11-25 00:26:21 +1100558 if (!channel_still_open())
Damien Millerb38eff82000-04-01 11:09:21 +1000559 break;
Damien Miller95def091999-11-25 00:26:21 +1100560 if (!waiting_termination) {
561 const char *s = "Waiting for forwarded connections to terminate...\r\n";
562 char *cp;
563 waiting_termination = 1;
564 buffer_append(&stderr_buffer, s, strlen(s));
565
566 /* Display list of open channels. */
567 cp = channel_open_message();
568 buffer_append(&stderr_buffer, cp, strlen(cp));
569 xfree(cp);
570 }
571 }
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000572 max_fd = MAX(connection_in, connection_out);
573 max_fd = MAX(max_fd, fdin);
574 max_fd = MAX(max_fd, fdout);
575 max_fd = MAX(max_fd, fderr);
576
Damien Miller95def091999-11-25 00:26:21 +1100577 /* Sleep in select() until we can do something. */
Damien Miller5e953212001-01-30 09:14:00 +1100578 wait_until_can_do_something(&readset, &writeset, &max_fd,
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000579 &nalloc, max_time_milliseconds);
Damien Miller95def091999-11-25 00:26:21 +1100580
581 /* Process any channel events. */
Damien Miller5e953212001-01-30 09:14:00 +1100582 channel_after_select(readset, writeset);
Damien Miller95def091999-11-25 00:26:21 +1100583
584 /* Process input from the client and from program stdout/stderr. */
Damien Miller5e953212001-01-30 09:14:00 +1100585 process_input(readset);
Damien Miller95def091999-11-25 00:26:21 +1100586
587 /* Process output to the client and to program stdin. */
Damien Miller5e953212001-01-30 09:14:00 +1100588 process_output(writeset);
Damien Miller95def091999-11-25 00:26:21 +1100589 }
Damien Miller5e953212001-01-30 09:14:00 +1100590 if (readset)
591 xfree(readset);
592 if (writeset)
593 xfree(writeset);
Damien Miller95def091999-11-25 00:26:21 +1100594
Damien Miller95def091999-11-25 00:26:21 +1100595 /* Cleanup and termination code. */
596
597 /* Wait until all output has been sent to the client. */
598 drain_output();
599
600 debug("End of interactive session; stdin %ld, stdout (read %ld, sent %ld), stderr %ld bytes.",
601 stdin_bytes, fdout_bytes, stdout_bytes, stderr_bytes);
602
603 /* Free and clear the buffers. */
604 buffer_free(&stdin_buffer);
605 buffer_free(&stdout_buffer);
606 buffer_free(&stderr_buffer);
607
608 /* Close the file descriptors. */
609 if (fdout != -1)
610 close(fdout);
611 fdout = -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000612 fdout_eof = 1;
Damien Miller95def091999-11-25 00:26:21 +1100613 if (fderr != -1)
614 close(fderr);
615 fderr = -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000616 fderr_eof = 1;
Damien Miller95def091999-11-25 00:26:21 +1100617 if (fdin != -1)
618 close(fdin);
619 fdin = -1;
620
Ben Lindstrom601e4362001-06-21 03:19:23 +0000621 channel_free_all();
Damien Miller95def091999-11-25 00:26:21 +1100622
Damien Miller95def091999-11-25 00:26:21 +1100623 /* We no longer want our SIGCHLD handler to be called. */
Kevin Stevese26a1552001-07-26 17:51:49 +0000624 mysignal(SIGCHLD, SIG_DFL);
Damien Miller95def091999-11-25 00:26:21 +1100625
Ben Lindstromec46e0b2001-06-09 01:27:31 +0000626 wait_pid = waitpid(-1, &wait_status, child_terminated ? WNOHANG : 0);
627 if (wait_pid == -1)
628 packet_disconnect("wait: %.100s", strerror(errno));
629 else if (wait_pid != pid)
630 error("Strange, wait returned pid %d, expected %d",
631 wait_pid, pid);
632
Damien Miller95def091999-11-25 00:26:21 +1100633 /* Check if it exited normally. */
634 if (WIFEXITED(wait_status)) {
635 /* Yes, normal exit. Get exit status and send it to the client. */
636 debug("Command exited with status %d.", WEXITSTATUS(wait_status));
637 packet_start(SSH_SMSG_EXITSTATUS);
638 packet_put_int(WEXITSTATUS(wait_status));
639 packet_send();
640 packet_write_wait();
641
Damien Miller5428f641999-11-25 11:54:57 +1100642 /*
643 * Wait for exit confirmation. Note that there might be
644 * other packets coming before it; however, the program has
645 * already died so we just ignore them. The client is
646 * supposed to respond with the confirmation when it receives
647 * the exit status.
648 */
Damien Miller95def091999-11-25 00:26:21 +1100649 do {
650 int plen;
651 type = packet_read(&plen);
652 }
653 while (type != SSH_CMSG_EXIT_CONFIRMATION);
654
655 debug("Received exit confirmation.");
656 return;
657 }
658 /* Check if the program terminated due to a signal. */
659 if (WIFSIGNALED(wait_status))
660 packet_disconnect("Command terminated on signal %d.",
661 WTERMSIG(wait_status));
662
663 /* Some weird exit cause. Just exit. */
664 packet_disconnect("wait returned status %04x.", wait_status);
665 /* NOTREACHED */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000666}
Damien Millerb38eff82000-04-01 11:09:21 +1000667
Damien Miller4af51302000-04-16 11:18:38 +1000668void
Ben Lindstrombddd5512001-07-04 04:53:53 +0000669server_loop2(Authctxt *authctxt)
Damien Millerefb4afe2000-04-12 18:45:05 +1000670{
Damien Miller5e953212001-01-30 09:14:00 +1100671 fd_set *readset = NULL, *writeset = NULL;
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000672 int rekeying = 0, max_fd, status, nalloc = 0;
Damien Millerefb4afe2000-04-12 18:45:05 +1000673 pid_t pid;
674
675 debug("Entering interactive session for SSH2.");
676
Ben Lindstromec46e0b2001-06-09 01:27:31 +0000677 mysignal(SIGCHLD, sigchld_handler);
Damien Millerefb4afe2000-04-12 18:45:05 +1000678 child_terminated = 0;
679 connection_in = packet_get_connection_in();
680 connection_out = packet_get_connection_out();
Damien Miller5e953212001-01-30 09:14:00 +1100681
682 max_fd = MAX(connection_in, connection_out);
Ben Lindstrombddd5512001-07-04 04:53:53 +0000683 xxx_authctxt = authctxt;
Damien Miller5e953212001-01-30 09:14:00 +1100684
Damien Millerefb4afe2000-04-12 18:45:05 +1000685 server_init_dispatch();
686
687 for (;;) {
688 process_buffered_input_packets();
Ben Lindstrom8e312f32001-04-04 23:50:21 +0000689
Ben Lindstroma3700052001-04-05 23:26:32 +0000690 rekeying = (xxx_kex != NULL && !xxx_kex->done);
Ben Lindstrom8e312f32001-04-04 23:50:21 +0000691
Ben Lindstrom8e312f32001-04-04 23:50:21 +0000692 if (!rekeying && packet_not_very_much_data_to_write())
Damien Millerefb4afe2000-04-12 18:45:05 +1000693 channel_output_poll();
Ben Lindstrom8e312f32001-04-04 23:50:21 +0000694 wait_until_can_do_something(&readset, &writeset, &max_fd,
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000695 &nalloc, 0);
Damien Miller43dc8da2000-11-29 15:55:17 +1100696 if (child_terminated) {
Damien Millerefb4afe2000-04-12 18:45:05 +1000697 while ((pid = waitpid(-1, &status, WNOHANG)) > 0)
698 session_close_by_pid(pid, status);
699 child_terminated = 0;
700 }
Ben Lindstrom8e312f32001-04-04 23:50:21 +0000701 if (!rekeying)
702 channel_after_select(readset, writeset);
Damien Miller5e953212001-01-30 09:14:00 +1100703 process_input(readset);
Ben Lindstrome34ab4c2001-04-07 01:12:11 +0000704 if (connection_closed)
705 break;
Damien Miller5e953212001-01-30 09:14:00 +1100706 process_output(writeset);
Damien Millerefb4afe2000-04-12 18:45:05 +1000707 }
Damien Miller5e953212001-01-30 09:14:00 +1100708 if (readset)
709 xfree(readset);
710 if (writeset)
711 xfree(writeset);
712
Kevin Stevese26a1552001-07-26 17:51:49 +0000713 mysignal(SIGCHLD, SIG_DFL);
Ben Lindstrom4983d5e2001-07-04 05:17:40 +0000714
Damien Millerefb4afe2000-04-12 18:45:05 +1000715 while ((pid = waitpid(-1, &status, WNOHANG)) > 0)
716 session_close_by_pid(pid, status);
Ben Lindstrom4983d5e2001-07-04 05:17:40 +0000717 /*
718 * there is a race between channel_free_all() killing children and
719 * children dying before kill()
720 */
Ben Lindstrom809744e2001-07-04 05:26:06 +0000721 channel_detach_all();
722 channel_stop_listening();
Ben Lindstrom4983d5e2001-07-04 05:17:40 +0000723
724 while (session_have_children()) {
725 pid = waitpid(-1, &status, 0);
726 if (pid > 0)
727 session_close_by_pid(pid, status);
728 else {
729 error("waitpid returned %d: %s", pid, strerror(errno));
730 break;
731 }
732 }
Ben Lindstrom809744e2001-07-04 05:26:06 +0000733 channel_free_all();
Damien Millerefb4afe2000-04-12 18:45:05 +1000734}
735
Ben Lindstrombba81212001-06-25 05:01:22 +0000736static void
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000737server_input_channel_failure(int type, int plen, void *ctxt)
738{
739 debug("Got CHANNEL_FAILURE for keepalive");
740 /*
Ben Lindstrom2f0304c2001-04-29 19:49:14 +0000741 * reset timeout, since we got a sane answer from the client.
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000742 * even if this was generated by something other than
743 * the bogus CHANNEL_REQUEST we send for keepalives.
744 */
745 client_alive_timeouts = 0;
746}
747
748
Ben Lindstrombba81212001-06-25 05:01:22 +0000749static void
Damien Miller62cee002000-09-23 17:15:56 +1100750server_input_stdin_data(int type, int plen, void *ctxt)
Damien Millerb38eff82000-04-01 11:09:21 +1000751{
752 char *data;
Ben Lindstrom46c16222000-12-22 01:43:59 +0000753 u_int data_len;
Damien Millerb38eff82000-04-01 11:09:21 +1000754
755 /* Stdin data from the client. Append it to the buffer. */
756 /* Ignore any data if the client has closed stdin. */
757 if (fdin == -1)
758 return;
759 data = packet_get_string(&data_len);
760 packet_integrity_check(plen, (4 + data_len), type);
761 buffer_append(&stdin_buffer, data, data_len);
762 memset(data, 0, data_len);
763 xfree(data);
764}
765
Ben Lindstrombba81212001-06-25 05:01:22 +0000766static void
Damien Miller62cee002000-09-23 17:15:56 +1100767server_input_eof(int type, int plen, void *ctxt)
Damien Millerb38eff82000-04-01 11:09:21 +1000768{
769 /*
770 * Eof from the client. The stdin descriptor to the
771 * program will be closed when all buffered data has
772 * drained.
773 */
774 debug("EOF received for stdin.");
775 packet_integrity_check(plen, 0, type);
776 stdin_eof = 1;
777}
778
Ben Lindstrombba81212001-06-25 05:01:22 +0000779static void
Damien Miller62cee002000-09-23 17:15:56 +1100780server_input_window_size(int type, int plen, void *ctxt)
Damien Millerb38eff82000-04-01 11:09:21 +1000781{
782 int row = packet_get_int();
783 int col = packet_get_int();
784 int xpixel = packet_get_int();
785 int ypixel = packet_get_int();
786
787 debug("Window change received.");
788 packet_integrity_check(plen, 4 * 4, type);
789 if (fdin != -1)
790 pty_change_window_size(fdin, row, col, xpixel, ypixel);
791}
792
Ben Lindstrombba81212001-06-25 05:01:22 +0000793static Channel *
Damien Miller0bc1bd82000-11-13 22:57:25 +1100794server_request_direct_tcpip(char *ctype)
Damien Millerefb4afe2000-04-12 18:45:05 +1000795{
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000796 Channel *c;
797 int sock;
Damien Miller4af51302000-04-16 11:18:38 +1000798 char *target, *originator;
799 int target_port, originator_port;
Damien Millerefb4afe2000-04-12 18:45:05 +1000800
Damien Miller4af51302000-04-16 11:18:38 +1000801 target = packet_get_string(NULL);
802 target_port = packet_get_int();
Damien Millerefb4afe2000-04-12 18:45:05 +1000803 originator = packet_get_string(NULL);
804 originator_port = packet_get_int();
Damien Miller4af51302000-04-16 11:18:38 +1000805 packet_done();
Damien Millerb1715dc2000-05-30 13:44:51 +1000806
Damien Miller0bc1bd82000-11-13 22:57:25 +1100807 debug("server_request_direct_tcpip: originator %s port %d, target %s port %d",
Damien Millerb1715dc2000-05-30 13:44:51 +1000808 originator, originator_port, target, target_port);
Damien Millerf6d9e222000-06-18 14:50:44 +1000809
Damien Millerefb4afe2000-04-12 18:45:05 +1000810 /* XXX check permission */
Damien Miller4af51302000-04-16 11:18:38 +1000811 sock = channel_connect_to(target, target_port);
812 xfree(target);
Damien Millerefb4afe2000-04-12 18:45:05 +1000813 xfree(originator);
814 if (sock < 0)
Damien Miller0bc1bd82000-11-13 22:57:25 +1100815 return NULL;
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000816 c = channel_new(ctype, SSH_CHANNEL_CONNECTING,
Damien Millere4340be2000-09-16 13:29:08 +1100817 sock, sock, -1, CHAN_TCP_WINDOW_DEFAULT,
Damien Miller69b69aa2000-10-28 14:19:58 +1100818 CHAN_TCP_PACKET_DEFAULT, 0, xstrdup("direct-tcpip"), 1);
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000819 if (c == NULL) {
820 error("server_request_direct_tcpip: channel_new failed");
821 close(sock);
822 }
823 return c;
Damien Miller0bc1bd82000-11-13 22:57:25 +1100824}
825
Ben Lindstrombba81212001-06-25 05:01:22 +0000826static Channel *
Damien Miller0bc1bd82000-11-13 22:57:25 +1100827server_request_session(char *ctype)
828{
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000829 Channel *c;
Damien Miller0bc1bd82000-11-13 22:57:25 +1100830
831 debug("input_session_request");
832 packet_done();
833 /*
834 * A server session has no fd to read or write until a
835 * CHANNEL_REQUEST for a shell is made, so we set the type to
836 * SSH_CHANNEL_LARVAL. Additionally, a callback for handling all
837 * CHANNEL_REQUEST messages is registered.
838 */
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000839 c = channel_new(ctype, SSH_CHANNEL_LARVAL,
840 -1, -1, -1, /*window size*/0, CHAN_SES_PACKET_DEFAULT,
Damien Miller0bc1bd82000-11-13 22:57:25 +1100841 0, xstrdup("server-session"), 1);
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000842 if (c == NULL) {
843 error("server_request_session: channel_new failed");
844 return NULL;
Damien Miller0bc1bd82000-11-13 22:57:25 +1100845 }
Ben Lindstrombddd5512001-07-04 04:53:53 +0000846 if (session_open(xxx_authctxt, c->self) != 1) {
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000847 debug("session open failed, free channel %d", c->self);
848 channel_free(c);
849 return NULL;
850 }
851 channel_register_callback(c->self, SSH2_MSG_CHANNEL_REQUEST,
852 session_input_channel_req, (void *)0);
853 channel_register_cleanup(c->self, session_close_by_channel);
854 return c;
Damien Millerefb4afe2000-04-12 18:45:05 +1000855}
856
Ben Lindstrombba81212001-06-25 05:01:22 +0000857static void
Damien Miller62cee002000-09-23 17:15:56 +1100858server_input_channel_open(int type, int plen, void *ctxt)
Damien Millerefb4afe2000-04-12 18:45:05 +1000859{
860 Channel *c = NULL;
861 char *ctype;
Ben Lindstrom46c16222000-12-22 01:43:59 +0000862 u_int len;
Damien Millerefb4afe2000-04-12 18:45:05 +1000863 int rchan;
864 int rmaxpack;
865 int rwindow;
866
867 ctype = packet_get_string(&len);
868 rchan = packet_get_int();
869 rwindow = packet_get_int();
870 rmaxpack = packet_get_int();
871
Damien Miller62cee002000-09-23 17:15:56 +1100872 debug("server_input_channel_open: ctype %s rchan %d win %d max %d",
Damien Millerefb4afe2000-04-12 18:45:05 +1000873 ctype, rchan, rwindow, rmaxpack);
874
875 if (strcmp(ctype, "session") == 0) {
Damien Miller0bc1bd82000-11-13 22:57:25 +1100876 c = server_request_session(ctype);
Damien Millerefb4afe2000-04-12 18:45:05 +1000877 } else if (strcmp(ctype, "direct-tcpip") == 0) {
Damien Miller0bc1bd82000-11-13 22:57:25 +1100878 c = server_request_direct_tcpip(ctype);
Damien Millerefb4afe2000-04-12 18:45:05 +1000879 }
880 if (c != NULL) {
Damien Miller0bc1bd82000-11-13 22:57:25 +1100881 debug("server_input_channel_open: confirm %s", ctype);
Damien Millerefb4afe2000-04-12 18:45:05 +1000882 c->remote_id = rchan;
883 c->remote_window = rwindow;
884 c->remote_maxpacket = rmaxpack;
Ben Lindstrom69128662001-05-08 20:07:39 +0000885 if (c->type != SSH_CHANNEL_CONNECTING) {
886 packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
887 packet_put_int(c->remote_id);
888 packet_put_int(c->self);
889 packet_put_int(c->local_window);
890 packet_put_int(c->local_maxpacket);
891 packet_send();
892 }
Damien Millerefb4afe2000-04-12 18:45:05 +1000893 } else {
Damien Miller0bc1bd82000-11-13 22:57:25 +1100894 debug("server_input_channel_open: failure %s", ctype);
Damien Millerefb4afe2000-04-12 18:45:05 +1000895 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
896 packet_put_int(rchan);
897 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
Ben Lindstromf3436742001-04-29 19:52:00 +0000898 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
Ben Lindstrom69128662001-05-08 20:07:39 +0000899 packet_put_cstring("open failed");
Ben Lindstromf3436742001-04-29 19:52:00 +0000900 packet_put_cstring("");
901 }
Damien Millerefb4afe2000-04-12 18:45:05 +1000902 packet_send();
903 }
904 xfree(ctype);
905}
906
Ben Lindstrombba81212001-06-25 05:01:22 +0000907static void
Damien Miller0bc1bd82000-11-13 22:57:25 +1100908server_input_global_request(int type, int plen, void *ctxt)
909{
910 char *rtype;
911 int want_reply;
912 int success = 0;
913
914 rtype = packet_get_string(NULL);
915 want_reply = packet_get_char();
916 debug("server_input_global_request: rtype %s want_reply %d", rtype, want_reply);
Kevin Stevesef4eea92001-02-05 12:42:17 +0000917
Ben Lindstrom7bb8b492001-03-17 00:47:54 +0000918 /* -R style forwarding */
Damien Miller0bc1bd82000-11-13 22:57:25 +1100919 if (strcmp(rtype, "tcpip-forward") == 0) {
920 struct passwd *pw;
921 char *listen_address;
922 u_short listen_port;
923
924 pw = auth_get_user();
925 if (pw == NULL)
926 fatal("server_input_global_request: no user");
927 listen_address = packet_get_string(NULL); /* XXX currently ignored */
928 listen_port = (u_short)packet_get_int();
929 debug("server_input_global_request: tcpip-forward listen %s port %d",
930 listen_address, listen_port);
931
932 /* check permissions */
933 if (!options.allow_tcp_forwarding ||
934 no_port_forwarding_flag ||
935 (listen_port < IPPORT_RESERVED && pw->pw_uid != 0)) {
936 success = 0;
937 packet_send_debug("Server has disabled port forwarding.");
938 } else {
939 /* Start listening on the port */
Kevin Steves12057502001-02-05 14:54:34 +0000940 success = channel_request_forwarding(
Damien Miller0bc1bd82000-11-13 22:57:25 +1100941 listen_address, listen_port,
942 /*unspec host_to_connect*/ "<unspec host>",
943 /*unspec port_to_connect*/ 0,
944 options.gateway_ports, /*remote*/ 1);
Damien Miller0bc1bd82000-11-13 22:57:25 +1100945 }
946 xfree(listen_address);
947 }
948 if (want_reply) {
949 packet_start(success ?
950 SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
951 packet_send();
952 packet_write_wait();
953 }
954 xfree(rtype);
955}
956
Ben Lindstrombba81212001-06-25 05:01:22 +0000957static void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000958server_init_dispatch_20(void)
Damien Millerefb4afe2000-04-12 18:45:05 +1000959{
960 debug("server_init_dispatch_20");
961 dispatch_init(&dispatch_protocol_error);
962 dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
963 dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
964 dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
965 dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
966 dispatch_set(SSH2_MSG_CHANNEL_OPEN, &server_input_channel_open);
967 dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
968 dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
969 dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &channel_input_channel_request);
970 dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
Damien Miller0bc1bd82000-11-13 22:57:25 +1100971 dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &server_input_global_request);
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000972 /* client_alive */
973 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &server_input_channel_failure);
Ben Lindstrom8ac91062001-04-04 17:57:54 +0000974 /* rekeying */
975 dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
Damien Millerefb4afe2000-04-12 18:45:05 +1000976}
Ben Lindstrombba81212001-06-25 05:01:22 +0000977static void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000978server_init_dispatch_13(void)
Damien Millerb38eff82000-04-01 11:09:21 +1000979{
980 debug("server_init_dispatch_13");
981 dispatch_init(NULL);
982 dispatch_set(SSH_CMSG_EOF, &server_input_eof);
983 dispatch_set(SSH_CMSG_STDIN_DATA, &server_input_stdin_data);
984 dispatch_set(SSH_CMSG_WINDOW_SIZE, &server_input_window_size);
985 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
986 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
987 dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
988 dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
989 dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
990 dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
991}
Ben Lindstrombba81212001-06-25 05:01:22 +0000992static void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000993server_init_dispatch_15(void)
Damien Millerb38eff82000-04-01 11:09:21 +1000994{
995 server_init_dispatch_13();
996 debug("server_init_dispatch_15");
997 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
998 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_oclose);
999}
Ben Lindstrombba81212001-06-25 05:01:22 +00001000static void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +00001001server_init_dispatch(void)
Damien Millerb38eff82000-04-01 11:09:21 +10001002{
Damien Millerefb4afe2000-04-12 18:45:05 +10001003 if (compat20)
1004 server_init_dispatch_20();
1005 else if (compat13)
Damien Millerb38eff82000-04-01 11:09:21 +10001006 server_init_dispatch_13();
1007 else
1008 server_init_dispatch_15();
1009}