blob: 5a5b1e37fa0d184a1a57fdb62333846b449858b4 [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 Lindstrom92a2e382001-03-05 06:59:27 +000014 * Copyright (c) 2000 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 Lindstrom5744dc42001-04-13 23:28:01 +000038RCSID("$OpenBSD: serverloop.c,v 1.61 2001/04/13 22:46:54 beck 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"
Damien Millerb38eff82000-04-01 11:09:21 +100046#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;
62
Damien Millerd4a8b7e1999-10-27 13:42:43 +100063static Buffer stdin_buffer; /* Buffer for stdin data. */
64static Buffer stdout_buffer; /* Buffer for stdout data. */
65static Buffer stderr_buffer; /* Buffer for stderr data. */
66static int fdin; /* Descriptor for stdin (for writing) */
67static int fdout; /* Descriptor for stdout (for reading);
68 May be same number as fdin. */
69static int fderr; /* Descriptor for stderr. May be -1. */
70static long stdin_bytes = 0; /* Number of bytes written to stdin. */
71static long stdout_bytes = 0; /* Number of stdout bytes sent to client. */
72static long stderr_bytes = 0; /* Number of stderr bytes sent to client. */
73static long fdout_bytes = 0; /* Number of stdout bytes read from program. */
74static int stdin_eof = 0; /* EOF message received from client. */
75static int fdout_eof = 0; /* EOF encountered reading from fdout. */
76static int fderr_eof = 0; /* EOF encountered readung from fderr. */
Damien Miller225736c2001-02-19 21:51:08 +110077static int fdin_is_tty = 0; /* fdin points to a tty. */
Damien Millerd4a8b7e1999-10-27 13:42:43 +100078static int connection_in; /* Connection to client (input). */
79static int connection_out; /* Connection to client (output). */
Ben Lindstrome34ab4c2001-04-07 01:12:11 +000080static int connection_closed = 0; /* Connection to client closed. */
81static u_int buffer_high; /* "Soft" max buffer size. */
Damien Millerd4a8b7e1999-10-27 13:42:43 +100082
Damien Miller5428f641999-11-25 11:54:57 +110083/*
84 * This SIGCHLD kludge is used to detect when the child exits. The server
85 * will exit after that, as soon as forwarded connections have terminated.
86 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +100087
Damien Miller166fca82000-04-20 07:42:21 +100088static pid_t child_pid; /* Pid of the child. */
Damien Millerd4a8b7e1999-10-27 13:42:43 +100089static volatile int child_terminated; /* The child has terminated. */
90static volatile int child_wait_status; /* Status from wait(). */
91
Damien Millerb38eff82000-04-01 11:09:21 +100092void server_init_dispatch(void);
93
Ben Lindstrom5744dc42001-04-13 23:28:01 +000094int client_alive_timeouts = 0;
95
Damien Miller4af51302000-04-16 11:18:38 +100096void
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 Miller166fca82000-04-20 07:42:21 +1000100 pid_t wait_pid;
101
Damien Miller95def091999-11-25 00:26:21 +1100102 debug("Received SIGCHLD.");
103 wait_pid = wait((int *) &child_wait_status);
104 if (wait_pid != -1) {
105 if (wait_pid != child_pid)
106 error("Strange, got SIGCHLD and wait returned pid %d but child is %d",
107 wait_pid, child_pid);
108 if (WIFEXITED(child_wait_status) ||
Damien Miller43dc8da2000-11-29 15:55:17 +1100109 WIFSIGNALED(child_wait_status))
Damien Miller95def091999-11-25 00:26:21 +1100110 child_terminated = 1;
111 }
112 signal(SIGCHLD, sigchld_handler);
113 errno = save_errno;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000114}
Damien Miller4af51302000-04-16 11:18:38 +1000115void
Damien Millerefb4afe2000-04-12 18:45:05 +1000116sigchld_handler2(int sig)
117{
118 int save_errno = errno;
119 debug("Received SIGCHLD.");
120 child_terminated = 1;
Kevin Stevesb6e773a2001-02-04 13:20:36 +0000121 mysignal(SIGCHLD, sigchld_handler2);
Damien Millerefb4afe2000-04-12 18:45:05 +1000122 errno = save_errno;
123}
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000124
Damien Miller95def091999-11-25 00:26:21 +1100125/*
Damien Miller95def091999-11-25 00:26:21 +1100126 * Make packets from buffered stderr data, and buffer it for sending
127 * to the client.
128 */
Damien Miller4af51302000-04-16 11:18:38 +1000129void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000130make_packets_from_stderr_data(void)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000131{
Damien Miller95def091999-11-25 00:26:21 +1100132 int len;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000133
Damien Miller95def091999-11-25 00:26:21 +1100134 /* Send buffered stderr data to the client. */
135 while (buffer_len(&stderr_buffer) > 0 &&
Damien Miller037a0dc1999-12-07 15:38:31 +1100136 packet_not_very_much_data_to_write()) {
Damien Miller95def091999-11-25 00:26:21 +1100137 len = buffer_len(&stderr_buffer);
138 if (packet_is_interactive()) {
139 if (len > 512)
140 len = 512;
141 } else {
142 /* Keep the packets at reasonable size. */
143 if (len > packet_get_maxsize())
144 len = packet_get_maxsize();
145 }
146 packet_start(SSH_SMSG_STDERR_DATA);
147 packet_put_string(buffer_ptr(&stderr_buffer), len);
148 packet_send();
149 buffer_consume(&stderr_buffer, len);
150 stderr_bytes += len;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000151 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000152}
153
Damien Miller95def091999-11-25 00:26:21 +1100154/*
155 * Make packets from buffered stdout data, and buffer it for sending to the
156 * client.
157 */
Damien Miller4af51302000-04-16 11:18:38 +1000158void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000159make_packets_from_stdout_data(void)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000160{
Damien Miller95def091999-11-25 00:26:21 +1100161 int len;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000162
Damien Miller95def091999-11-25 00:26:21 +1100163 /* Send buffered stdout data to the client. */
164 while (buffer_len(&stdout_buffer) > 0 &&
Damien Miller037a0dc1999-12-07 15:38:31 +1100165 packet_not_very_much_data_to_write()) {
Damien Miller95def091999-11-25 00:26:21 +1100166 len = buffer_len(&stdout_buffer);
167 if (packet_is_interactive()) {
168 if (len > 512)
169 len = 512;
170 } else {
171 /* Keep the packets at reasonable size. */
172 if (len > packet_get_maxsize())
Kevin Stevesef4eea92001-02-05 12:42:17 +0000173 len = packet_get_maxsize();
Damien Miller95def091999-11-25 00:26:21 +1100174 }
175 packet_start(SSH_SMSG_STDOUT_DATA);
176 packet_put_string(buffer_ptr(&stdout_buffer), len);
177 packet_send();
178 buffer_consume(&stdout_buffer, len);
179 stdout_bytes += len;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000180 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000181}
182
Damien Miller95def091999-11-25 00:26:21 +1100183/*
184 * Sleep in select() until we can do something. This will initialize the
185 * select masks. Upon return, the masks will indicate which descriptors
186 * have data or can accept data. Optionally, a maximum time can be specified
187 * for the duration of the wait (0 = infinite).
188 */
Damien Miller4af51302000-04-16 11:18:38 +1000189void
Damien Miller5e953212001-01-30 09:14:00 +1100190wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
191 u_int max_time_milliseconds)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000192{
Damien Miller95def091999-11-25 00:26:21 +1100193 struct timeval tv, *tvp;
194 int ret;
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000195 int client_alive_scheduled = 0;
196
197 /*
198 * if using client_alive, set the max timeout accordingly,
199 * and indicate that this particular timeout was for client
200 * alive by setting the client_alive_scheduled flag.
201 *
202 * this could be randomized somewhat to make traffic
203 * analysis more difficult, but we're not doing it yet.
204 */
205 if (max_time_milliseconds == 0 && options.client_alive_interval) {
206 client_alive_scheduled = 1;
207 max_time_milliseconds = options.client_alive_interval * 1000;
208 } else
209 client_alive_scheduled = 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000210
Damien Miller95def091999-11-25 00:26:21 +1100211 /* When select fails we restart from here. */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000212retry_select:
213
Damien Miller5e953212001-01-30 09:14:00 +1100214 /* Allocate and update select() masks for channel descriptors. */
Ben Lindstrombe2cc432001-04-04 23:46:07 +0000215 channel_prepare_select(readsetp, writesetp, maxfdp, 0);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000216
Damien Millerefb4afe2000-04-12 18:45:05 +1000217 if (compat20) {
Damien Millere247cc42000-05-07 12:03:14 +1000218 /* wrong: bad condition XXX */
Damien Millerefb4afe2000-04-12 18:45:05 +1000219 if (channel_not_very_much_buffered_data())
Damien Miller5e953212001-01-30 09:14:00 +1100220 FD_SET(connection_in, *readsetp);
Damien Millerefb4afe2000-04-12 18:45:05 +1000221 } else {
Damien Millerb1715dc2000-05-30 13:44:51 +1000222 /*
223 * Read packets from the client unless we have too much
224 * buffered stdin or channel data.
225 */
226 if (buffer_len(&stdin_buffer) < buffer_high &&
Damien Millerefb4afe2000-04-12 18:45:05 +1000227 channel_not_very_much_buffered_data())
Damien Miller5e953212001-01-30 09:14:00 +1100228 FD_SET(connection_in, *readsetp);
Damien Millerb1715dc2000-05-30 13:44:51 +1000229 /*
230 * If there is not too much data already buffered going to
231 * the client, try to get some more data from the program.
232 */
233 if (packet_not_very_much_data_to_write()) {
234 if (!fdout_eof)
Damien Miller5e953212001-01-30 09:14:00 +1100235 FD_SET(fdout, *readsetp);
Damien Millerb1715dc2000-05-30 13:44:51 +1000236 if (!fderr_eof)
Damien Miller5e953212001-01-30 09:14:00 +1100237 FD_SET(fderr, *readsetp);
Damien Millerb1715dc2000-05-30 13:44:51 +1000238 }
239 /*
240 * If we have buffered data, try to write some of that data
241 * to the program.
242 */
243 if (fdin != -1 && buffer_len(&stdin_buffer) > 0)
Damien Miller5e953212001-01-30 09:14:00 +1100244 FD_SET(fdin, *writesetp);
Damien Millerefb4afe2000-04-12 18:45:05 +1000245 }
Damien Miller95def091999-11-25 00:26:21 +1100246
Damien Miller5428f641999-11-25 11:54:57 +1100247 /*
248 * If we have buffered packet data going to the client, mark that
249 * descriptor.
250 */
Damien Miller95def091999-11-25 00:26:21 +1100251 if (packet_have_data_to_write())
Damien Miller5e953212001-01-30 09:14:00 +1100252 FD_SET(connection_out, *writesetp);
Damien Miller95def091999-11-25 00:26:21 +1100253
Damien Miller5428f641999-11-25 11:54:57 +1100254 /*
255 * If child has terminated and there is enough buffer space to read
256 * from it, then read as much as is available and exit.
257 */
Damien Miller95def091999-11-25 00:26:21 +1100258 if (child_terminated && packet_not_very_much_data_to_write())
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000259 if (max_time_milliseconds == 0 || client_alive_scheduled)
Damien Miller95def091999-11-25 00:26:21 +1100260 max_time_milliseconds = 100;
261
262 if (max_time_milliseconds == 0)
263 tvp = NULL;
264 else {
265 tv.tv_sec = max_time_milliseconds / 1000;
266 tv.tv_usec = 1000 * (max_time_milliseconds % 1000);
267 tvp = &tv;
268 }
Damien Millerefb4afe2000-04-12 18:45:05 +1000269 if (tvp!=NULL)
Ben Lindstromf4c73112001-03-05 05:58:23 +0000270 debug3("tvp!=NULL kid %d mili %d", child_terminated, max_time_milliseconds);
Damien Miller95def091999-11-25 00:26:21 +1100271
272 /* Wait for something to happen, or the timeout to expire. */
Damien Miller5e953212001-01-30 09:14:00 +1100273 ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
Damien Miller95def091999-11-25 00:26:21 +1100274
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000275 if (ret == -1) {
Damien Miller95def091999-11-25 00:26:21 +1100276 if (errno != EINTR)
277 error("select: %.100s", strerror(errno));
278 else
279 goto retry_select;
280 }
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000281 if (ret == 0 && client_alive_scheduled) {
282 /* timeout, check to see how many we have had */
283 client_alive_timeouts++;
284
285 if (client_alive_timeouts > options.client_alive_count_max ) {
286 packet_disconnect(
287 "Timeout, your session not responding.");
288 } else {
289 /*
290 * send a bogus channel request with "wantreply"
291 * we should get back a failure
292 */
293 int id;
294
295 id = channel_find_open();
296 if (id != -1) {
297 channel_request_start(id,
298 "keepalive@openssh.com", 1);
299 packet_send();
300 } else
301 packet_disconnect(
302 "No open channels after timeout!");
303 }
304 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000305}
306
Damien Miller95def091999-11-25 00:26:21 +1100307/*
308 * Processes input from the client and the program. Input data is stored
309 * in buffers and processed later.
310 */
Damien Miller4af51302000-04-16 11:18:38 +1000311void
Damien Miller95def091999-11-25 00:26:21 +1100312process_input(fd_set * readset)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000313{
Damien Miller95def091999-11-25 00:26:21 +1100314 int len;
315 char buf[16384];
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000316
Damien Miller95def091999-11-25 00:26:21 +1100317 /* Read and buffer any input data from the client. */
318 if (FD_ISSET(connection_in, readset)) {
319 len = read(connection_in, buf, sizeof(buf));
320 if (len == 0) {
321 verbose("Connection closed by remote host.");
Ben Lindstrome34ab4c2001-04-07 01:12:11 +0000322 connection_closed = 1;
323 if (compat20)
324 return;
Damien Miller95def091999-11-25 00:26:21 +1100325 fatal_cleanup();
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000326 } else if (len < 0) {
327 if (errno != EINTR && errno != EAGAIN) {
328 verbose("Read error from remote host: %.100s", strerror(errno));
329 fatal_cleanup();
330 }
331 } else {
332 /* Buffer any received data. */
333 packet_process_incoming(buf, len);
Damien Miller95def091999-11-25 00:26:21 +1100334 }
Damien Miller95def091999-11-25 00:26:21 +1100335 }
Damien Millerefb4afe2000-04-12 18:45:05 +1000336 if (compat20)
337 return;
338
Damien Miller95def091999-11-25 00:26:21 +1100339 /* Read and buffer any available stdout data from the program. */
340 if (!fdout_eof && FD_ISSET(fdout, readset)) {
341 len = read(fdout, buf, sizeof(buf));
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000342 if (len < 0 && (errno == EINTR || errno == EAGAIN)) {
343 /* do nothing */
344 } else if (len <= 0) {
Damien Miller95def091999-11-25 00:26:21 +1100345 fdout_eof = 1;
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000346 } else {
Damien Miller95def091999-11-25 00:26:21 +1100347 buffer_append(&stdout_buffer, buf, len);
348 fdout_bytes += len;
349 }
350 }
351 /* Read and buffer any available stderr data from the program. */
352 if (!fderr_eof && FD_ISSET(fderr, readset)) {
353 len = read(fderr, buf, sizeof(buf));
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000354 if (len < 0 && (errno == EINTR || errno == EAGAIN)) {
355 /* do nothing */
356 } else if (len <= 0) {
Damien Miller95def091999-11-25 00:26:21 +1100357 fderr_eof = 1;
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000358 } else {
Damien Miller95def091999-11-25 00:26:21 +1100359 buffer_append(&stderr_buffer, buf, len);
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000360 }
Damien Miller95def091999-11-25 00:26:21 +1100361 }
362}
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000363
Damien Miller95def091999-11-25 00:26:21 +1100364/*
365 * Sends data from internal buffers to client program stdin.
366 */
Damien Miller4af51302000-04-16 11:18:38 +1000367void
Damien Miller95def091999-11-25 00:26:21 +1100368process_output(fd_set * writeset)
369{
Ben Lindstromaa630de2001-02-10 23:44:47 +0000370 struct termios tio;
Damien Miller95def091999-11-25 00:26:21 +1100371 int len;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000372
Damien Miller95def091999-11-25 00:26:21 +1100373 /* Write buffered data to program stdin. */
Damien Millerefb4afe2000-04-12 18:45:05 +1000374 if (!compat20 && fdin != -1 && FD_ISSET(fdin, writeset)) {
Damien Miller95def091999-11-25 00:26:21 +1100375 len = write(fdin, buffer_ptr(&stdin_buffer),
Damien Miller037a0dc1999-12-07 15:38:31 +1100376 buffer_len(&stdin_buffer));
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000377 if (len < 0 && (errno == EINTR || errno == EAGAIN)) {
378 /* do nothing */
379 } else if (len <= 0) {
Damien Miller95def091999-11-25 00:26:21 +1100380#ifdef USE_PIPES
381 close(fdin);
382#else
Damien Millerb38eff82000-04-01 11:09:21 +1000383 if (fdin != fdout)
Damien Miller95def091999-11-25 00:26:21 +1100384 close(fdin);
385 else
386 shutdown(fdin, SHUT_WR); /* We will no longer send. */
387#endif
388 fdin = -1;
389 } else {
Ben Lindstromaa630de2001-02-10 23:44:47 +0000390 /* Successful write. */
Damien Miller225736c2001-02-19 21:51:08 +1100391 if (fdin_is_tty && tcgetattr(fdin, &tio) == 0 &&
Damien Miller79438cc2001-02-16 12:34:57 +1100392 !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
Kevin Stevesb7f036f2001-02-15 17:27:15 +0000393 /*
394 * Simulate echo to reduce the impact of
395 * traffic analysis
396 */
Ben Lindstrome229b252001-03-05 06:28:06 +0000397 packet_send_ignore(len);
Ben Lindstromaa630de2001-02-10 23:44:47 +0000398 packet_send();
399 }
400 /* Consume the data from the buffer. */
Damien Miller95def091999-11-25 00:26:21 +1100401 buffer_consume(&stdin_buffer, len);
402 /* Update the count of bytes written to the program. */
403 stdin_bytes += len;
404 }
405 }
406 /* Send any buffered packet data to the client. */
407 if (FD_ISSET(connection_out, writeset))
408 packet_write_poll();
409}
410
411/*
412 * Wait until all buffered output has been sent to the client.
413 * This is used when the program terminates.
414 */
Damien Miller4af51302000-04-16 11:18:38 +1000415void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000416drain_output(void)
Damien Miller95def091999-11-25 00:26:21 +1100417{
418 /* Send any buffered stdout data to the client. */
419 if (buffer_len(&stdout_buffer) > 0) {
420 packet_start(SSH_SMSG_STDOUT_DATA);
421 packet_put_string(buffer_ptr(&stdout_buffer),
422 buffer_len(&stdout_buffer));
423 packet_send();
424 /* Update the count of sent bytes. */
425 stdout_bytes += buffer_len(&stdout_buffer);
426 }
427 /* Send any buffered stderr data to the client. */
428 if (buffer_len(&stderr_buffer) > 0) {
429 packet_start(SSH_SMSG_STDERR_DATA);
430 packet_put_string(buffer_ptr(&stderr_buffer),
431 buffer_len(&stderr_buffer));
432 packet_send();
433 /* Update the count of sent bytes. */
434 stderr_bytes += buffer_len(&stderr_buffer);
435 }
436 /* Wait until all buffered data has been written to the client. */
437 packet_write_wait();
438}
439
Damien Miller4af51302000-04-16 11:18:38 +1000440void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000441process_buffered_input_packets(void)
Damien Millerb38eff82000-04-01 11:09:21 +1000442{
Ben Lindstrom8ac91062001-04-04 17:57:54 +0000443 dispatch_run(DISPATCH_NONBLOCK, NULL, compat20 ? xxx_kex : NULL);
Damien Millerb38eff82000-04-01 11:09:21 +1000444}
445
Damien Miller95def091999-11-25 00:26:21 +1100446/*
447 * Performs the interactive session. This handles data transmission between
448 * the client and the program. Note that the notion of stdin, stdout, and
449 * stderr in this function is sort of reversed: this function writes to
450 * stdin (of the child program), and reads from stdout and stderr (of the
451 * child program).
452 */
Damien Miller4af51302000-04-16 11:18:38 +1000453void
Damien Miller166fca82000-04-20 07:42:21 +1000454server_loop(pid_t pid, int fdin_arg, int fdout_arg, int fderr_arg)
Damien Miller95def091999-11-25 00:26:21 +1100455{
Damien Miller5e953212001-01-30 09:14:00 +1100456 fd_set *readset = NULL, *writeset = NULL;
457 int max_fd;
Damien Miller166fca82000-04-20 07:42:21 +1000458 int wait_status; /* Status returned by wait(). */
459 pid_t wait_pid; /* pid returned by wait(). */
Damien Miller95def091999-11-25 00:26:21 +1100460 int waiting_termination = 0; /* Have displayed waiting close message. */
Ben Lindstrom46c16222000-12-22 01:43:59 +0000461 u_int max_time_milliseconds;
462 u_int previous_stdout_buffer_bytes;
463 u_int stdout_buffer_bytes;
Damien Miller95def091999-11-25 00:26:21 +1100464 int type;
465
466 debug("Entering interactive session.");
467
468 /* Initialize the SIGCHLD kludge. */
469 child_pid = pid;
470 child_terminated = 0;
471 signal(SIGCHLD, sigchld_handler);
472
473 /* Initialize our global variables. */
474 fdin = fdin_arg;
475 fdout = fdout_arg;
476 fderr = fderr_arg;
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000477
478 /* nonblocking IO */
479 set_nonblock(fdin);
480 set_nonblock(fdout);
Damien Miller7d6656c2000-05-20 15:22:36 +1000481 /* we don't have stderr for interactive terminal sessions, see below */
482 if (fderr != -1)
483 set_nonblock(fderr);
Damien Millerdcb6ecd2000-05-17 22:34:22 +1000484
Damien Miller225736c2001-02-19 21:51:08 +1100485 if (!(datafellows & SSH_BUG_IGNOREMSG) && isatty(fdin))
486 fdin_is_tty = 1;
487
Damien Miller95def091999-11-25 00:26:21 +1100488 connection_in = packet_get_connection_in();
489 connection_out = packet_get_connection_out();
490
491 previous_stdout_buffer_bytes = 0;
492
493 /* Set approximate I/O buffer size. */
494 if (packet_is_interactive())
495 buffer_high = 4096;
496 else
497 buffer_high = 64 * 1024;
498
499 /* Initialize max_fd to the maximum of the known file descriptors. */
Damien Miller5e953212001-01-30 09:14:00 +1100500 max_fd = MAX(fdin, fdout);
501 if (fderr != -1)
502 max_fd = MAX(max_fd, fderr);
503 max_fd = MAX(max_fd, connection_in);
504 max_fd = MAX(max_fd, connection_out);
Damien Miller95def091999-11-25 00:26:21 +1100505
506 /* Initialize Initialize buffers. */
507 buffer_init(&stdin_buffer);
508 buffer_init(&stdout_buffer);
509 buffer_init(&stderr_buffer);
510
Damien Miller5428f641999-11-25 11:54:57 +1100511 /*
512 * If we have no separate fderr (which is the case when we have a pty
513 * - there we cannot make difference between data sent to stdout and
514 * stderr), indicate that we have seen an EOF from stderr. This way
515 * we don\'t need to check the descriptor everywhere.
516 */
Damien Miller95def091999-11-25 00:26:21 +1100517 if (fderr == -1)
518 fderr_eof = 1;
519
Damien Millerb38eff82000-04-01 11:09:21 +1000520 server_init_dispatch();
521
Damien Miller95def091999-11-25 00:26:21 +1100522 /* Main loop of the server for the interactive session mode. */
523 for (;;) {
Damien Miller95def091999-11-25 00:26:21 +1100524
525 /* Process buffered packets from the client. */
526 process_buffered_input_packets();
527
Damien Miller5428f641999-11-25 11:54:57 +1100528 /*
529 * If we have received eof, and there is no more pending
530 * input data, cause a real eof by closing fdin.
531 */
Damien Miller95def091999-11-25 00:26:21 +1100532 if (stdin_eof && fdin != -1 && buffer_len(&stdin_buffer) == 0) {
533#ifdef USE_PIPES
534 close(fdin);
535#else
Damien Millerb38eff82000-04-01 11:09:21 +1000536 if (fdin != fdout)
Damien Miller95def091999-11-25 00:26:21 +1100537 close(fdin);
538 else
539 shutdown(fdin, SHUT_WR); /* We will no longer send. */
540#endif
541 fdin = -1;
542 }
Damien Miller5428f641999-11-25 11:54:57 +1100543 /* Make packets from buffered stderr data to send to the client. */
Damien Miller95def091999-11-25 00:26:21 +1100544 make_packets_from_stderr_data();
545
Damien Miller5428f641999-11-25 11:54:57 +1100546 /*
547 * Make packets from buffered stdout data to send to the
548 * client. If there is very little to send, this arranges to
549 * not send them now, but to wait a short while to see if we
550 * are getting more data. This is necessary, as some systems
551 * wake up readers from a pty after each separate character.
552 */
Damien Miller95def091999-11-25 00:26:21 +1100553 max_time_milliseconds = 0;
554 stdout_buffer_bytes = buffer_len(&stdout_buffer);
555 if (stdout_buffer_bytes != 0 && stdout_buffer_bytes < 256 &&
556 stdout_buffer_bytes != previous_stdout_buffer_bytes) {
557 /* try again after a while */
558 max_time_milliseconds = 10;
559 } else {
560 /* Send it now. */
561 make_packets_from_stdout_data();
562 }
563 previous_stdout_buffer_bytes = buffer_len(&stdout_buffer);
564
565 /* Send channel data to the client. */
566 if (packet_not_very_much_data_to_write())
567 channel_output_poll();
568
Damien Miller5428f641999-11-25 11:54:57 +1100569 /*
570 * Bail out of the loop if the program has closed its output
571 * descriptors, and we have no more data to send to the
572 * client, and there is no pending buffered data.
573 */
Damien Miller43dc8da2000-11-29 15:55:17 +1100574 if (fdout_eof && fderr_eof && !packet_have_data_to_write() &&
575 buffer_len(&stdout_buffer) == 0 && buffer_len(&stderr_buffer) == 0) {
Damien Miller95def091999-11-25 00:26:21 +1100576 if (!channel_still_open())
Damien Millerb38eff82000-04-01 11:09:21 +1000577 break;
Damien Miller95def091999-11-25 00:26:21 +1100578 if (!waiting_termination) {
579 const char *s = "Waiting for forwarded connections to terminate...\r\n";
580 char *cp;
581 waiting_termination = 1;
582 buffer_append(&stderr_buffer, s, strlen(s));
583
584 /* Display list of open channels. */
585 cp = channel_open_message();
586 buffer_append(&stderr_buffer, cp, strlen(cp));
587 xfree(cp);
588 }
589 }
590 /* Sleep in select() until we can do something. */
Damien Miller5e953212001-01-30 09:14:00 +1100591 wait_until_can_do_something(&readset, &writeset, &max_fd,
592 max_time_milliseconds);
Damien Miller95def091999-11-25 00:26:21 +1100593
594 /* Process any channel events. */
Damien Miller5e953212001-01-30 09:14:00 +1100595 channel_after_select(readset, writeset);
Damien Miller95def091999-11-25 00:26:21 +1100596
597 /* Process input from the client and from program stdout/stderr. */
Damien Miller5e953212001-01-30 09:14:00 +1100598 process_input(readset);
Damien Miller95def091999-11-25 00:26:21 +1100599
600 /* Process output to the client and to program stdin. */
Damien Miller5e953212001-01-30 09:14:00 +1100601 process_output(writeset);
Damien Miller95def091999-11-25 00:26:21 +1100602 }
Damien Miller5e953212001-01-30 09:14:00 +1100603 if (readset)
604 xfree(readset);
605 if (writeset)
606 xfree(writeset);
Damien Miller95def091999-11-25 00:26:21 +1100607
Damien Miller95def091999-11-25 00:26:21 +1100608 /* Cleanup and termination code. */
609
610 /* Wait until all output has been sent to the client. */
611 drain_output();
612
613 debug("End of interactive session; stdin %ld, stdout (read %ld, sent %ld), stderr %ld bytes.",
614 stdin_bytes, fdout_bytes, stdout_bytes, stderr_bytes);
615
616 /* Free and clear the buffers. */
617 buffer_free(&stdin_buffer);
618 buffer_free(&stdout_buffer);
619 buffer_free(&stderr_buffer);
620
621 /* Close the file descriptors. */
622 if (fdout != -1)
623 close(fdout);
624 fdout = -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000625 fdout_eof = 1;
Damien Miller95def091999-11-25 00:26:21 +1100626 if (fderr != -1)
627 close(fderr);
628 fderr = -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000629 fderr_eof = 1;
Damien Miller95def091999-11-25 00:26:21 +1100630 if (fdin != -1)
631 close(fdin);
632 fdin = -1;
633
634 /* Stop listening for channels; this removes unix domain sockets. */
635 channel_stop_listening();
636
637 /* Wait for the child to exit. Get its exit status. */
638 wait_pid = wait(&wait_status);
Ben Lindstrom46c16222000-12-22 01:43:59 +0000639 if (wait_pid == -1) {
Damien Miller95def091999-11-25 00:26:21 +1100640 /*
641 * It is possible that the wait was handled by SIGCHLD
642 * handler. This may result in either: this call
643 * returning with EINTR, or: this call returning ECHILD.
644 */
645 if (child_terminated)
646 wait_status = child_wait_status;
647 else
648 packet_disconnect("wait: %.100s", strerror(errno));
649 } else {
650 /* Check if it matches the process we forked. */
651 if (wait_pid != pid)
652 error("Strange, wait returned pid %d, expected %d",
Damien Milleraae6c611999-12-06 11:47:28 +1100653 wait_pid, pid);
Damien Miller95def091999-11-25 00:26:21 +1100654 }
655
656 /* We no longer want our SIGCHLD handler to be called. */
657 signal(SIGCHLD, SIG_DFL);
658
659 /* Check if it exited normally. */
660 if (WIFEXITED(wait_status)) {
661 /* Yes, normal exit. Get exit status and send it to the client. */
662 debug("Command exited with status %d.", WEXITSTATUS(wait_status));
663 packet_start(SSH_SMSG_EXITSTATUS);
664 packet_put_int(WEXITSTATUS(wait_status));
665 packet_send();
666 packet_write_wait();
667
Damien Miller5428f641999-11-25 11:54:57 +1100668 /*
669 * Wait for exit confirmation. Note that there might be
670 * other packets coming before it; however, the program has
671 * already died so we just ignore them. The client is
672 * supposed to respond with the confirmation when it receives
673 * the exit status.
674 */
Damien Miller95def091999-11-25 00:26:21 +1100675 do {
676 int plen;
677 type = packet_read(&plen);
678 }
679 while (type != SSH_CMSG_EXIT_CONFIRMATION);
680
681 debug("Received exit confirmation.");
682 return;
683 }
684 /* Check if the program terminated due to a signal. */
685 if (WIFSIGNALED(wait_status))
686 packet_disconnect("Command terminated on signal %d.",
687 WTERMSIG(wait_status));
688
689 /* Some weird exit cause. Just exit. */
690 packet_disconnect("wait returned status %04x.", wait_status);
691 /* NOTREACHED */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000692}
Damien Millerb38eff82000-04-01 11:09:21 +1000693
Damien Miller4af51302000-04-16 11:18:38 +1000694void
Damien Millerefb4afe2000-04-12 18:45:05 +1000695server_loop2(void)
696{
Damien Miller5e953212001-01-30 09:14:00 +1100697 fd_set *readset = NULL, *writeset = NULL;
Ben Lindstrome34ab4c2001-04-07 01:12:11 +0000698 int rekeying = 0, max_fd, status;
Damien Millerefb4afe2000-04-12 18:45:05 +1000699 pid_t pid;
700
701 debug("Entering interactive session for SSH2.");
702
Kevin Stevesb6e773a2001-02-04 13:20:36 +0000703 mysignal(SIGCHLD, sigchld_handler2);
Damien Millerefb4afe2000-04-12 18:45:05 +1000704 child_terminated = 0;
705 connection_in = packet_get_connection_in();
706 connection_out = packet_get_connection_out();
Damien Miller5e953212001-01-30 09:14:00 +1100707
708 max_fd = MAX(connection_in, connection_out);
709
Damien Millerefb4afe2000-04-12 18:45:05 +1000710 server_init_dispatch();
711
712 for (;;) {
713 process_buffered_input_packets();
Ben Lindstrom8e312f32001-04-04 23:50:21 +0000714
Ben Lindstroma3700052001-04-05 23:26:32 +0000715 rekeying = (xxx_kex != NULL && !xxx_kex->done);
Ben Lindstrom8e312f32001-04-04 23:50:21 +0000716
Ben Lindstrom8e312f32001-04-04 23:50:21 +0000717 if (!rekeying && packet_not_very_much_data_to_write())
Damien Millerefb4afe2000-04-12 18:45:05 +1000718 channel_output_poll();
Ben Lindstrom8e312f32001-04-04 23:50:21 +0000719 wait_until_can_do_something(&readset, &writeset, &max_fd,
720 rekeying);
Damien Miller43dc8da2000-11-29 15:55:17 +1100721 if (child_terminated) {
Damien Millerefb4afe2000-04-12 18:45:05 +1000722 while ((pid = waitpid(-1, &status, WNOHANG)) > 0)
723 session_close_by_pid(pid, status);
724 child_terminated = 0;
725 }
Ben Lindstrom8e312f32001-04-04 23:50:21 +0000726 if (!rekeying)
727 channel_after_select(readset, writeset);
Damien Miller5e953212001-01-30 09:14:00 +1100728 process_input(readset);
Ben Lindstrome34ab4c2001-04-07 01:12:11 +0000729 if (connection_closed)
730 break;
Damien Miller5e953212001-01-30 09:14:00 +1100731 process_output(writeset);
Damien Millerefb4afe2000-04-12 18:45:05 +1000732 }
Damien Miller5e953212001-01-30 09:14:00 +1100733 if (readset)
734 xfree(readset);
735 if (writeset)
736 xfree(writeset);
737
Damien Millerefb4afe2000-04-12 18:45:05 +1000738 signal(SIGCHLD, SIG_DFL);
739 while ((pid = waitpid(-1, &status, WNOHANG)) > 0)
740 session_close_by_pid(pid, status);
741 channel_stop_listening();
742}
743
Damien Millerb38eff82000-04-01 11:09:21 +1000744void
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000745server_input_channel_failure(int type, int plen, void *ctxt)
746{
747 debug("Got CHANNEL_FAILURE for keepalive");
748 /*
749 * reset timeout, since we got a sane answer from the client.
750 * even if this was generated by something other than
751 * the bogus CHANNEL_REQUEST we send for keepalives.
752 */
753 client_alive_timeouts = 0;
754}
755
756
757void
Damien Miller62cee002000-09-23 17:15:56 +1100758server_input_stdin_data(int type, int plen, void *ctxt)
Damien Millerb38eff82000-04-01 11:09:21 +1000759{
760 char *data;
Ben Lindstrom46c16222000-12-22 01:43:59 +0000761 u_int data_len;
Damien Millerb38eff82000-04-01 11:09:21 +1000762
763 /* Stdin data from the client. Append it to the buffer. */
764 /* Ignore any data if the client has closed stdin. */
765 if (fdin == -1)
766 return;
767 data = packet_get_string(&data_len);
768 packet_integrity_check(plen, (4 + data_len), type);
769 buffer_append(&stdin_buffer, data, data_len);
770 memset(data, 0, data_len);
771 xfree(data);
772}
773
774void
Damien Miller62cee002000-09-23 17:15:56 +1100775server_input_eof(int type, int plen, void *ctxt)
Damien Millerb38eff82000-04-01 11:09:21 +1000776{
777 /*
778 * Eof from the client. The stdin descriptor to the
779 * program will be closed when all buffered data has
780 * drained.
781 */
782 debug("EOF received for stdin.");
783 packet_integrity_check(plen, 0, type);
784 stdin_eof = 1;
785}
786
787void
Damien Miller62cee002000-09-23 17:15:56 +1100788server_input_window_size(int type, int plen, void *ctxt)
Damien Millerb38eff82000-04-01 11:09:21 +1000789{
790 int row = packet_get_int();
791 int col = packet_get_int();
792 int xpixel = packet_get_int();
793 int ypixel = packet_get_int();
794
795 debug("Window change received.");
796 packet_integrity_check(plen, 4 * 4, type);
797 if (fdin != -1)
798 pty_change_window_size(fdin, row, col, xpixel, ypixel);
799}
800
Damien Miller0bc1bd82000-11-13 22:57:25 +1100801Channel *
802server_request_direct_tcpip(char *ctype)
Damien Millerefb4afe2000-04-12 18:45:05 +1000803{
Damien Miller0bc1bd82000-11-13 22:57:25 +1100804 int sock, newch;
Damien Miller4af51302000-04-16 11:18:38 +1000805 char *target, *originator;
806 int target_port, originator_port;
Damien Millerefb4afe2000-04-12 18:45:05 +1000807
Damien Miller4af51302000-04-16 11:18:38 +1000808 target = packet_get_string(NULL);
809 target_port = packet_get_int();
Damien Millerefb4afe2000-04-12 18:45:05 +1000810 originator = packet_get_string(NULL);
811 originator_port = packet_get_int();
Damien Miller4af51302000-04-16 11:18:38 +1000812 packet_done();
Damien Millerb1715dc2000-05-30 13:44:51 +1000813
Damien Miller0bc1bd82000-11-13 22:57:25 +1100814 debug("server_request_direct_tcpip: originator %s port %d, target %s port %d",
Damien Millerb1715dc2000-05-30 13:44:51 +1000815 originator, originator_port, target, target_port);
Damien Millerf6d9e222000-06-18 14:50:44 +1000816
Damien Millerefb4afe2000-04-12 18:45:05 +1000817 /* XXX check permission */
Damien Miller4af51302000-04-16 11:18:38 +1000818 sock = channel_connect_to(target, target_port);
819 xfree(target);
Damien Millerefb4afe2000-04-12 18:45:05 +1000820 xfree(originator);
821 if (sock < 0)
Damien Miller0bc1bd82000-11-13 22:57:25 +1100822 return NULL;
Ben Lindstrom7ad97102000-12-06 01:42:49 +0000823 newch = channel_new(ctype, SSH_CHANNEL_CONNECTING,
Damien Millere4340be2000-09-16 13:29:08 +1100824 sock, sock, -1, CHAN_TCP_WINDOW_DEFAULT,
Damien Miller69b69aa2000-10-28 14:19:58 +1100825 CHAN_TCP_PACKET_DEFAULT, 0, xstrdup("direct-tcpip"), 1);
Damien Miller0bc1bd82000-11-13 22:57:25 +1100826 return (newch >= 0) ? channel_lookup(newch) : NULL;
827}
828
829Channel *
830server_request_session(char *ctype)
831{
832 int newch;
833
834 debug("input_session_request");
835 packet_done();
836 /*
837 * A server session has no fd to read or write until a
838 * CHANNEL_REQUEST for a shell is made, so we set the type to
839 * SSH_CHANNEL_LARVAL. Additionally, a callback for handling all
840 * CHANNEL_REQUEST messages is registered.
841 */
842 newch = channel_new(ctype, SSH_CHANNEL_LARVAL,
843 -1, -1, -1, 0, CHAN_SES_PACKET_DEFAULT,
844 0, xstrdup("server-session"), 1);
845 if (session_open(newch) == 1) {
846 channel_register_callback(newch, SSH2_MSG_CHANNEL_REQUEST,
847 session_input_channel_req, (void *)0);
848 channel_register_cleanup(newch, session_close_by_channel);
849 return channel_lookup(newch);
850 } else {
851 debug("session open failed, free channel %d", newch);
852 channel_free(newch);
853 }
854 return NULL;
Damien Millerefb4afe2000-04-12 18:45:05 +1000855}
856
Damien Miller4af51302000-04-16 11:18:38 +1000857void
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;
885
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 } else {
Damien Miller0bc1bd82000-11-13 22:57:25 +1100893 debug("server_input_channel_open: failure %s", ctype);
Damien Millerefb4afe2000-04-12 18:45:05 +1000894 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
895 packet_put_int(rchan);
896 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
897 packet_put_cstring("bla bla");
898 packet_put_cstring("");
899 packet_send();
900 }
901 xfree(ctype);
902}
903
Kevin Stevesef4eea92001-02-05 12:42:17 +0000904void
Damien Miller0bc1bd82000-11-13 22:57:25 +1100905server_input_global_request(int type, int plen, void *ctxt)
906{
907 char *rtype;
908 int want_reply;
909 int success = 0;
910
911 rtype = packet_get_string(NULL);
912 want_reply = packet_get_char();
913 debug("server_input_global_request: rtype %s want_reply %d", rtype, want_reply);
Kevin Stevesef4eea92001-02-05 12:42:17 +0000914
Ben Lindstrom7bb8b492001-03-17 00:47:54 +0000915 /* -R style forwarding */
Damien Miller0bc1bd82000-11-13 22:57:25 +1100916 if (strcmp(rtype, "tcpip-forward") == 0) {
917 struct passwd *pw;
918 char *listen_address;
919 u_short listen_port;
920
921 pw = auth_get_user();
922 if (pw == NULL)
923 fatal("server_input_global_request: no user");
924 listen_address = packet_get_string(NULL); /* XXX currently ignored */
925 listen_port = (u_short)packet_get_int();
926 debug("server_input_global_request: tcpip-forward listen %s port %d",
927 listen_address, listen_port);
928
929 /* check permissions */
930 if (!options.allow_tcp_forwarding ||
931 no_port_forwarding_flag ||
932 (listen_port < IPPORT_RESERVED && pw->pw_uid != 0)) {
933 success = 0;
934 packet_send_debug("Server has disabled port forwarding.");
935 } else {
936 /* Start listening on the port */
Kevin Steves12057502001-02-05 14:54:34 +0000937 success = channel_request_forwarding(
Damien Miller0bc1bd82000-11-13 22:57:25 +1100938 listen_address, listen_port,
939 /*unspec host_to_connect*/ "<unspec host>",
940 /*unspec port_to_connect*/ 0,
941 options.gateway_ports, /*remote*/ 1);
Damien Miller0bc1bd82000-11-13 22:57:25 +1100942 }
943 xfree(listen_address);
944 }
945 if (want_reply) {
946 packet_start(success ?
947 SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
948 packet_send();
949 packet_write_wait();
950 }
951 xfree(rtype);
952}
953
Damien Miller4af51302000-04-16 11:18:38 +1000954void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000955server_init_dispatch_20(void)
Damien Millerefb4afe2000-04-12 18:45:05 +1000956{
957 debug("server_init_dispatch_20");
958 dispatch_init(&dispatch_protocol_error);
959 dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
960 dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
961 dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
962 dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
963 dispatch_set(SSH2_MSG_CHANNEL_OPEN, &server_input_channel_open);
964 dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
965 dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
966 dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &channel_input_channel_request);
967 dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
Damien Miller0bc1bd82000-11-13 22:57:25 +1100968 dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &server_input_global_request);
Ben Lindstrom5744dc42001-04-13 23:28:01 +0000969 /* client_alive */
970 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &server_input_channel_failure);
Ben Lindstrom8ac91062001-04-04 17:57:54 +0000971 /* rekeying */
972 dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
Damien Millerefb4afe2000-04-12 18:45:05 +1000973}
Damien Miller4af51302000-04-16 11:18:38 +1000974void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000975server_init_dispatch_13(void)
Damien Millerb38eff82000-04-01 11:09:21 +1000976{
977 debug("server_init_dispatch_13");
978 dispatch_init(NULL);
979 dispatch_set(SSH_CMSG_EOF, &server_input_eof);
980 dispatch_set(SSH_CMSG_STDIN_DATA, &server_input_stdin_data);
981 dispatch_set(SSH_CMSG_WINDOW_SIZE, &server_input_window_size);
982 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
983 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
984 dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
985 dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
986 dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
987 dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
988}
Damien Miller4af51302000-04-16 11:18:38 +1000989void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000990server_init_dispatch_15(void)
Damien Millerb38eff82000-04-01 11:09:21 +1000991{
992 server_init_dispatch_13();
993 debug("server_init_dispatch_15");
994 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
995 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_oclose);
996}
Damien Miller4af51302000-04-16 11:18:38 +1000997void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000998server_init_dispatch(void)
Damien Millerb38eff82000-04-01 11:09:21 +1000999{
Damien Millerefb4afe2000-04-12 18:45:05 +10001000 if (compat20)
1001 server_init_dispatch_20();
1002 else if (compat13)
Damien Millerb38eff82000-04-01 11:09:21 +10001003 server_init_dispatch_13();
1004 else
1005 server_init_dispatch_15();
1006}
Ben Lindstrom5744dc42001-04-13 23:28:01 +00001007