]>
Commit | Line | Data |
---|---|---|
31652869 | 1 | /* $OpenBSD: serverloop.c,v 1.144 2006/08/03 03:34:42 deraadt Exp $ */ |
8efc0c15 | 2 | /* |
5260325f | 3 | * Author: Tatu Ylonen <ylo@cs.hut.fi> |
4 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland | |
5 | * All rights reserved | |
5260325f | 6 | * Server main loop for handling the interactive session. |
bcbf86ec | 7 | * |
8 | * As far as I am concerned, the code I have written for this software | |
9 | * can be used freely for any purpose. Any derived versions of this | |
10 | * software must be clearly marked as such, and if the derived work is | |
11 | * incompatible with the protocol description in the RFC file, it must be | |
12 | * called by a name other than "ssh" or "Secure Shell". | |
13 | * | |
e78a59f5 | 14 | * SSH2 support by Markus Friedl. |
a96070d4 | 15 | * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved. |
bcbf86ec | 16 | * |
17 | * Redistribution and use in source and binary forms, with or without | |
18 | * modification, are permitted provided that the following conditions | |
19 | * are met: | |
20 | * 1. Redistributions of source code must retain the above copyright | |
21 | * notice, this list of conditions and the following disclaimer. | |
22 | * 2. Redistributions in binary form must reproduce the above copyright | |
23 | * notice, this list of conditions and the following disclaimer in the | |
24 | * documentation and/or other materials provided with the distribution. | |
25 | * | |
26 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR | |
27 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES | |
28 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. | |
29 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, | |
30 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | |
31 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | |
32 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | |
33 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
34 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | |
35 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
e78a59f5 | 36 | */ |
8efc0c15 | 37 | |
38 | #include "includes.h" | |
aa2eae64 | 39 | |
40 | #include <sys/types.h> | |
536c14e8 | 41 | #include <sys/param.h> |
aa2eae64 | 42 | #include <sys/wait.h> |
9794d008 | 43 | #include <sys/socket.h> |
e264ac72 | 44 | #ifdef HAVE_SYS_TIME_H |
45 | # include <sys/time.h> | |
46 | #endif | |
9794d008 | 47 | |
48 | #include <netinet/in.h> | |
1d3e026f | 49 | |
028094f4 | 50 | #include <errno.h> |
d3221cca | 51 | #include <fcntl.h> |
b1842393 | 52 | #include <pwd.h> |
ada68823 | 53 | #include <signal.h> |
00146caa | 54 | #include <string.h> |
1d3e026f | 55 | #include <termios.h> |
67514848 | 56 | #include <unistd.h> |
31652869 | 57 | #include <stdarg.h> |
a22aff1f | 58 | |
8efc0c15 | 59 | #include "xmalloc.h" |
8efc0c15 | 60 | #include "packet.h" |
61 | #include "buffer.h" | |
42f11eb2 | 62 | #include "log.h" |
8efc0c15 | 63 | #include "servconf.h" |
00e842d8 | 64 | #include "canohost.h" |
1729c161 | 65 | #include "sshpty.h" |
a5efa1bb | 66 | #include "channels.h" |
7368a6c8 | 67 | #include "compat.h" |
42f11eb2 | 68 | #include "ssh1.h" |
e78a59f5 | 69 | #include "ssh2.h" |
31652869 | 70 | #include "key.h" |
71 | #include "cipher.h" | |
72 | #include "kex.h" | |
73 | #include "hostfile.h" | |
59c97189 | 74 | #include "auth.h" |
e78a59f5 | 75 | #include "session.h" |
7368a6c8 | 76 | #include "dispatch.h" |
38c295d6 | 77 | #include "auth-options.h" |
42f11eb2 | 78 | #include "serverloop.h" |
79 | #include "misc.h" | |
8efc0c15 | 80 | |
33de75a3 | 81 | extern ServerOptions options; |
82 | ||
7a37c112 | 83 | /* XXX */ |
84 | extern Kex *xxx_kex; | |
2362db19 | 85 | extern Authctxt *the_authctxt; |
0bbbf2a4 | 86 | extern int use_privsep; |
7a37c112 | 87 | |
8efc0c15 | 88 | static Buffer stdin_buffer; /* Buffer for stdin data. */ |
89 | static Buffer stdout_buffer; /* Buffer for stdout data. */ | |
90 | static Buffer stderr_buffer; /* Buffer for stderr data. */ | |
91 | static int fdin; /* Descriptor for stdin (for writing) */ | |
92 | static int fdout; /* Descriptor for stdout (for reading); | |
93 | May be same number as fdin. */ | |
94 | static int fderr; /* Descriptor for stderr. May be -1. */ | |
95 | static long stdin_bytes = 0; /* Number of bytes written to stdin. */ | |
96 | static long stdout_bytes = 0; /* Number of stdout bytes sent to client. */ | |
97 | static long stderr_bytes = 0; /* Number of stderr bytes sent to client. */ | |
98 | static long fdout_bytes = 0; /* Number of stdout bytes read from program. */ | |
99 | static int stdin_eof = 0; /* EOF message received from client. */ | |
100 | static int fdout_eof = 0; /* EOF encountered reading from fdout. */ | |
101 | static int fderr_eof = 0; /* EOF encountered readung from fderr. */ | |
e68225b2 | 102 | static int fdin_is_tty = 0; /* fdin points to a tty. */ |
8efc0c15 | 103 | static int connection_in; /* Connection to client (input). */ |
104 | static int connection_out; /* Connection to client (output). */ | |
cc94bd38 | 105 | static int connection_closed = 0; /* Connection to client closed. */ |
106 | static u_int buffer_high; /* "Soft" max buffer size. */ | |
72176c0e | 107 | static int client_alive_timeouts = 0; |
8efc0c15 | 108 | |
aa3378df | 109 | /* |
110 | * This SIGCHLD kludge is used to detect when the child exits. The server | |
111 | * will exit after that, as soon as forwarded connections have terminated. | |
112 | */ | |
396c147e | 113 | |
7a934d1b | 114 | static volatile sig_atomic_t child_terminated = 0; /* The child has terminated. */ |
8efc0c15 | 115 | |
0bbbf2a4 | 116 | /* Cleanup on signals (!use_privsep case only) */ |
117 | static volatile sig_atomic_t received_sigterm = 0; | |
118 | ||
396c147e | 119 | /* prototypes */ |
120 | static void server_init_dispatch(void); | |
7368a6c8 | 121 | |
a10be357 | 122 | /* |
123 | * we write to this pipe if a SIGCHLD is caught in order to avoid | |
124 | * the race between select() and child_terminated | |
125 | */ | |
126 | static int notify_pipe[2]; | |
127 | static void | |
128 | notify_setup(void) | |
129 | { | |
130 | if (pipe(notify_pipe) < 0) { | |
131 | error("pipe(notify_pipe) failed %s", strerror(errno)); | |
132 | } else if ((fcntl(notify_pipe[0], F_SETFD, 1) == -1) || | |
133 | (fcntl(notify_pipe[1], F_SETFD, 1) == -1)) { | |
134 | error("fcntl(notify_pipe, F_SETFD) failed %s", strerror(errno)); | |
135 | close(notify_pipe[0]); | |
136 | close(notify_pipe[1]); | |
137 | } else { | |
138 | set_nonblock(notify_pipe[0]); | |
139 | set_nonblock(notify_pipe[1]); | |
140 | return; | |
141 | } | |
142 | notify_pipe[0] = -1; /* read end */ | |
143 | notify_pipe[1] = -1; /* write end */ | |
144 | } | |
145 | static void | |
146 | notify_parent(void) | |
147 | { | |
148 | if (notify_pipe[1] != -1) | |
149 | write(notify_pipe[1], "", 1); | |
150 | } | |
151 | static void | |
152 | notify_prepare(fd_set *readset) | |
153 | { | |
154 | if (notify_pipe[0] != -1) | |
155 | FD_SET(notify_pipe[0], readset); | |
156 | } | |
157 | static void | |
158 | notify_done(fd_set *readset) | |
159 | { | |
160 | char c; | |
161 | ||
162 | if (notify_pipe[0] != -1 && FD_ISSET(notify_pipe[0], readset)) | |
163 | while (read(notify_pipe[0], &c, 1) != -1) | |
164 | debug2("notify_done: reading"); | |
165 | } | |
166 | ||
3efa8ea9 | 167 | /*ARGSUSED*/ |
396c147e | 168 | static void |
5260325f | 169 | sigchld_handler(int sig) |
e78a59f5 | 170 | { |
171 | int save_errno = errno; | |
e78a59f5 | 172 | child_terminated = 1; |
ef51930f | 173 | #ifndef _UNICOS |
c9130033 | 174 | mysignal(SIGCHLD, sigchld_handler); |
ef51930f | 175 | #endif |
a10be357 | 176 | notify_parent(); |
e78a59f5 | 177 | errno = save_errno; |
178 | } | |
8efc0c15 | 179 | |
3efa8ea9 | 180 | /*ARGSUSED*/ |
0bbbf2a4 | 181 | static void |
182 | sigterm_handler(int sig) | |
183 | { | |
184 | received_sigterm = sig; | |
185 | } | |
186 | ||
5260325f | 187 | /* |
188 | * Make packets from buffered stderr data, and buffer it for sending | |
189 | * to the client. | |
190 | */ | |
396c147e | 191 | static void |
5ca51e19 | 192 | make_packets_from_stderr_data(void) |
8efc0c15 | 193 | { |
a27002e5 | 194 | u_int len; |
5260325f | 195 | |
196 | /* Send buffered stderr data to the client. */ | |
197 | while (buffer_len(&stderr_buffer) > 0 && | |
a408af76 | 198 | packet_not_very_much_data_to_write()) { |
5260325f | 199 | len = buffer_len(&stderr_buffer); |
200 | if (packet_is_interactive()) { | |
201 | if (len > 512) | |
202 | len = 512; | |
203 | } else { | |
204 | /* Keep the packets at reasonable size. */ | |
205 | if (len > packet_get_maxsize()) | |
206 | len = packet_get_maxsize(); | |
207 | } | |
208 | packet_start(SSH_SMSG_STDERR_DATA); | |
209 | packet_put_string(buffer_ptr(&stderr_buffer), len); | |
210 | packet_send(); | |
211 | buffer_consume(&stderr_buffer, len); | |
212 | stderr_bytes += len; | |
8efc0c15 | 213 | } |
8efc0c15 | 214 | } |
215 | ||
5260325f | 216 | /* |
217 | * Make packets from buffered stdout data, and buffer it for sending to the | |
218 | * client. | |
219 | */ | |
396c147e | 220 | static void |
5ca51e19 | 221 | make_packets_from_stdout_data(void) |
8efc0c15 | 222 | { |
a27002e5 | 223 | u_int len; |
5260325f | 224 | |
225 | /* Send buffered stdout data to the client. */ | |
226 | while (buffer_len(&stdout_buffer) > 0 && | |
a408af76 | 227 | packet_not_very_much_data_to_write()) { |
5260325f | 228 | len = buffer_len(&stdout_buffer); |
229 | if (packet_is_interactive()) { | |
230 | if (len > 512) | |
231 | len = 512; | |
232 | } else { | |
233 | /* Keep the packets at reasonable size. */ | |
234 | if (len > packet_get_maxsize()) | |
2b87da3b | 235 | len = packet_get_maxsize(); |
5260325f | 236 | } |
237 | packet_start(SSH_SMSG_STDOUT_DATA); | |
238 | packet_put_string(buffer_ptr(&stdout_buffer), len); | |
239 | packet_send(); | |
240 | buffer_consume(&stdout_buffer, len); | |
241 | stdout_bytes += len; | |
8efc0c15 | 242 | } |
8efc0c15 | 243 | } |
244 | ||
72176c0e | 245 | static void |
246 | client_alive_check(void) | |
247 | { | |
95ae2076 | 248 | int channel_id; |
99416ceb | 249 | |
72176c0e | 250 | /* timeout, check to see how many we have had */ |
251 | if (++client_alive_timeouts > options.client_alive_count_max) | |
252 | packet_disconnect("Timeout, your session not responding."); | |
253 | ||
72176c0e | 254 | /* |
95ae2076 | 255 | * send a bogus global/channel request with "wantreply", |
72176c0e | 256 | * we should get back a failure |
257 | */ | |
95ae2076 | 258 | if ((channel_id = channel_find_open()) == -1) { |
259 | packet_start(SSH2_MSG_GLOBAL_REQUEST); | |
260 | packet_put_cstring("keepalive@openssh.com"); | |
261 | packet_put_char(1); /* boolean: want reply */ | |
262 | } else { | |
263 | channel_request_start(channel_id, "keepalive@openssh.com", 1); | |
264 | } | |
72176c0e | 265 | packet_send(); |
266 | } | |
267 | ||
5260325f | 268 | /* |
269 | * Sleep in select() until we can do something. This will initialize the | |
270 | * select masks. Upon return, the masks will indicate which descriptors | |
271 | * have data or can accept data. Optionally, a maximum time can be specified | |
272 | * for the duration of the wait (0 = infinite). | |
273 | */ | |
396c147e | 274 | static void |
39929cdb | 275 | wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp, int *maxfdp, |
9a995072 | 276 | u_int *nallocp, u_int max_time_milliseconds) |
8efc0c15 | 277 | { |
5260325f | 278 | struct timeval tv, *tvp; |
279 | int ret; | |
3ffc6336 | 280 | int client_alive_scheduled = 0; |
281 | ||
282 | /* | |
184eed6a | 283 | * if using client_alive, set the max timeout accordingly, |
3ffc6336 | 284 | * and indicate that this particular timeout was for client |
285 | * alive by setting the client_alive_scheduled flag. | |
286 | * | |
287 | * this could be randomized somewhat to make traffic | |
184eed6a | 288 | * analysis more difficult, but we're not doing it yet. |
3ffc6336 | 289 | */ |
2c5b1791 | 290 | if (compat20 && |
291 | max_time_milliseconds == 0 && options.client_alive_interval) { | |
39aefe7b | 292 | client_alive_scheduled = 1; |
3ffc6336 | 293 | max_time_milliseconds = options.client_alive_interval * 1000; |
2c5b1791 | 294 | } |
8efc0c15 | 295 | |
39929cdb | 296 | /* Allocate and update select() masks for channel descriptors. */ |
489aa2e9 | 297 | channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, 0); |
5260325f | 298 | |
e78a59f5 | 299 | if (compat20) { |
0c139bd1 | 300 | #if 0 |
1d1ffb87 | 301 | /* wrong: bad condition XXX */ |
e78a59f5 | 302 | if (channel_not_very_much_buffered_data()) |
0c139bd1 | 303 | #endif |
304 | FD_SET(connection_in, *readsetp); | |
e78a59f5 | 305 | } else { |
71276795 | 306 | /* |
307 | * Read packets from the client unless we have too much | |
308 | * buffered stdin or channel data. | |
309 | */ | |
310 | if (buffer_len(&stdin_buffer) < buffer_high && | |
e78a59f5 | 311 | channel_not_very_much_buffered_data()) |
39929cdb | 312 | FD_SET(connection_in, *readsetp); |
71276795 | 313 | /* |
314 | * If there is not too much data already buffered going to | |
315 | * the client, try to get some more data from the program. | |
316 | */ | |
317 | if (packet_not_very_much_data_to_write()) { | |
318 | if (!fdout_eof) | |
39929cdb | 319 | FD_SET(fdout, *readsetp); |
71276795 | 320 | if (!fderr_eof) |
39929cdb | 321 | FD_SET(fderr, *readsetp); |
71276795 | 322 | } |
323 | /* | |
324 | * If we have buffered data, try to write some of that data | |
325 | * to the program. | |
326 | */ | |
327 | if (fdin != -1 && buffer_len(&stdin_buffer) > 0) | |
39929cdb | 328 | FD_SET(fdin, *writesetp); |
e78a59f5 | 329 | } |
a10be357 | 330 | notify_prepare(*readsetp); |
5260325f | 331 | |
aa3378df | 332 | /* |
333 | * If we have buffered packet data going to the client, mark that | |
334 | * descriptor. | |
335 | */ | |
5260325f | 336 | if (packet_have_data_to_write()) |
39929cdb | 337 | FD_SET(connection_out, *writesetp); |
5260325f | 338 | |
aa3378df | 339 | /* |
340 | * If child has terminated and there is enough buffer space to read | |
341 | * from it, then read as much as is available and exit. | |
342 | */ | |
5260325f | 343 | if (child_terminated && packet_not_very_much_data_to_write()) |
3ffc6336 | 344 | if (max_time_milliseconds == 0 || client_alive_scheduled) |
5260325f | 345 | max_time_milliseconds = 100; |
346 | ||
347 | if (max_time_milliseconds == 0) | |
348 | tvp = NULL; | |
349 | else { | |
350 | tv.tv_sec = max_time_milliseconds / 1000; | |
351 | tv.tv_usec = 1000 * (max_time_milliseconds % 1000); | |
352 | tvp = &tv; | |
353 | } | |
8efc0c15 | 354 | |
5260325f | 355 | /* Wait for something to happen, or the timeout to expire. */ |
39929cdb | 356 | ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp); |
8efc0c15 | 357 | |
3ffc6336 | 358 | if (ret == -1) { |
b3ad8fe6 | 359 | memset(*readsetp, 0, *nallocp); |
360 | memset(*writesetp, 0, *nallocp); | |
5260325f | 361 | if (errno != EINTR) |
362 | error("select: %.100s", strerror(errno)); | |
418e724c | 363 | } else if (ret == 0 && client_alive_scheduled) |
72176c0e | 364 | client_alive_check(); |
a10be357 | 365 | |
366 | notify_done(*readsetp); | |
8efc0c15 | 367 | } |
368 | ||
5260325f | 369 | /* |
370 | * Processes input from the client and the program. Input data is stored | |
371 | * in buffers and processed later. | |
372 | */ | |
396c147e | 373 | static void |
b476adfa | 374 | process_input(fd_set *readset) |
5260325f | 375 | { |
376 | int len; | |
377 | char buf[16384]; | |
378 | ||
379 | /* Read and buffer any input data from the client. */ | |
380 | if (FD_ISSET(connection_in, readset)) { | |
381 | len = read(connection_in, buf, sizeof(buf)); | |
382 | if (len == 0) { | |
00e842d8 | 383 | verbose("Connection closed by %.100s", |
384 | get_remote_ipaddr()); | |
cc94bd38 | 385 | connection_closed = 1; |
386 | if (compat20) | |
387 | return; | |
2362db19 | 388 | cleanup_exit(255); |
0e73cc53 | 389 | } else if (len < 0) { |
390 | if (errno != EINTR && errno != EAGAIN) { | |
00e842d8 | 391 | verbose("Read error from remote host " |
392 | "%.100s: %.100s", | |
393 | get_remote_ipaddr(), strerror(errno)); | |
2362db19 | 394 | cleanup_exit(255); |
0e73cc53 | 395 | } |
396 | } else { | |
397 | /* Buffer any received data. */ | |
398 | packet_process_incoming(buf, len); | |
5260325f | 399 | } |
5260325f | 400 | } |
e78a59f5 | 401 | if (compat20) |
402 | return; | |
403 | ||
5260325f | 404 | /* Read and buffer any available stdout data from the program. */ |
405 | if (!fdout_eof && FD_ISSET(fdout, readset)) { | |
ea8c44d9 | 406 | errno = 0; |
5260325f | 407 | len = read(fdout, buf, sizeof(buf)); |
0e73cc53 | 408 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) { |
409 | /* do nothing */ | |
24a87055 | 410 | #ifndef PTY_ZEROREAD |
0e73cc53 | 411 | } else if (len <= 0) { |
ea8c44d9 | 412 | #else |
9c04d67d | 413 | } else if ((!isatty(fdout) && len <= 0) || |
414 | (isatty(fdout) && (len < 0 || (len == 0 && errno != 0)))) { | |
ea8c44d9 | 415 | #endif |
5260325f | 416 | fdout_eof = 1; |
0e73cc53 | 417 | } else { |
5260325f | 418 | buffer_append(&stdout_buffer, buf, len); |
419 | fdout_bytes += len; | |
420 | } | |
421 | } | |
422 | /* Read and buffer any available stderr data from the program. */ | |
423 | if (!fderr_eof && FD_ISSET(fderr, readset)) { | |
ea8c44d9 | 424 | errno = 0; |
5260325f | 425 | len = read(fderr, buf, sizeof(buf)); |
0e73cc53 | 426 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) { |
427 | /* do nothing */ | |
24a87055 | 428 | #ifndef PTY_ZEROREAD |
0e73cc53 | 429 | } else if (len <= 0) { |
ea8c44d9 | 430 | #else |
9c04d67d | 431 | } else if ((!isatty(fderr) && len <= 0) || |
432 | (isatty(fderr) && (len < 0 || (len == 0 && errno != 0)))) { | |
ea8c44d9 | 433 | #endif |
5260325f | 434 | fderr_eof = 1; |
0e73cc53 | 435 | } else { |
5260325f | 436 | buffer_append(&stderr_buffer, buf, len); |
0e73cc53 | 437 | } |
5260325f | 438 | } |
439 | } | |
8efc0c15 | 440 | |
5260325f | 441 | /* |
442 | * Sends data from internal buffers to client program stdin. | |
443 | */ | |
396c147e | 444 | static void |
b476adfa | 445 | process_output(fd_set *writeset) |
8efc0c15 | 446 | { |
4ef922e3 | 447 | struct termios tio; |
780a9951 | 448 | u_char *data; |
449 | u_int dlen; | |
5260325f | 450 | int len; |
451 | ||
452 | /* Write buffered data to program stdin. */ | |
e78a59f5 | 453 | if (!compat20 && fdin != -1 && FD_ISSET(fdin, writeset)) { |
780a9951 | 454 | data = buffer_ptr(&stdin_buffer); |
455 | dlen = buffer_len(&stdin_buffer); | |
456 | len = write(fdin, data, dlen); | |
0e73cc53 | 457 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) { |
458 | /* do nothing */ | |
459 | } else if (len <= 0) { | |
7368a6c8 | 460 | if (fdin != fdout) |
5260325f | 461 | close(fdin); |
462 | else | |
463 | shutdown(fdin, SHUT_WR); /* We will no longer send. */ | |
5260325f | 464 | fdin = -1; |
465 | } else { | |
4ef922e3 | 466 | /* Successful write. */ |
780a9951 | 467 | if (fdin_is_tty && dlen >= 1 && data[0] != '\r' && |
468 | tcgetattr(fdin, &tio) == 0 && | |
0ae4fe1d | 469 | !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) { |
62da27dd | 470 | /* |
471 | * Simulate echo to reduce the impact of | |
472 | * traffic analysis | |
473 | */ | |
95ce5599 | 474 | packet_send_ignore(len); |
4ef922e3 | 475 | packet_send(); |
476 | } | |
477 | /* Consume the data from the buffer. */ | |
5260325f | 478 | buffer_consume(&stdin_buffer, len); |
479 | /* Update the count of bytes written to the program. */ | |
480 | stdin_bytes += len; | |
481 | } | |
8efc0c15 | 482 | } |
5260325f | 483 | /* Send any buffered packet data to the client. */ |
484 | if (FD_ISSET(connection_out, writeset)) | |
485 | packet_write_poll(); | |
8efc0c15 | 486 | } |
487 | ||
5260325f | 488 | /* |
489 | * Wait until all buffered output has been sent to the client. | |
490 | * This is used when the program terminates. | |
491 | */ | |
396c147e | 492 | static void |
5ca51e19 | 493 | drain_output(void) |
8efc0c15 | 494 | { |
5260325f | 495 | /* Send any buffered stdout data to the client. */ |
496 | if (buffer_len(&stdout_buffer) > 0) { | |
497 | packet_start(SSH_SMSG_STDOUT_DATA); | |
498 | packet_put_string(buffer_ptr(&stdout_buffer), | |
499 | buffer_len(&stdout_buffer)); | |
500 | packet_send(); | |
501 | /* Update the count of sent bytes. */ | |
502 | stdout_bytes += buffer_len(&stdout_buffer); | |
503 | } | |
504 | /* Send any buffered stderr data to the client. */ | |
505 | if (buffer_len(&stderr_buffer) > 0) { | |
506 | packet_start(SSH_SMSG_STDERR_DATA); | |
507 | packet_put_string(buffer_ptr(&stderr_buffer), | |
508 | buffer_len(&stderr_buffer)); | |
509 | packet_send(); | |
510 | /* Update the count of sent bytes. */ | |
511 | stderr_bytes += buffer_len(&stderr_buffer); | |
512 | } | |
513 | /* Wait until all buffered data has been written to the client. */ | |
514 | packet_write_wait(); | |
8efc0c15 | 515 | } |
516 | ||
396c147e | 517 | static void |
5ca51e19 | 518 | process_buffered_input_packets(void) |
7368a6c8 | 519 | { |
7a37c112 | 520 | dispatch_run(DISPATCH_NONBLOCK, NULL, compat20 ? xxx_kex : NULL); |
7368a6c8 | 521 | } |
522 | ||
5260325f | 523 | /* |
524 | * Performs the interactive session. This handles data transmission between | |
525 | * the client and the program. Note that the notion of stdin, stdout, and | |
526 | * stderr in this function is sort of reversed: this function writes to | |
527 | * stdin (of the child program), and reads from stdout and stderr (of the | |
528 | * child program). | |
529 | */ | |
6ae2364d | 530 | void |
9da5c3c9 | 531 | server_loop(pid_t pid, int fdin_arg, int fdout_arg, int fderr_arg) |
8efc0c15 | 532 | { |
39929cdb | 533 | fd_set *readset = NULL, *writeset = NULL; |
9a995072 | 534 | int max_fd = 0; |
535 | u_int nalloc = 0; | |
9da5c3c9 | 536 | int wait_status; /* Status returned by wait(). */ |
537 | pid_t wait_pid; /* pid returned by wait(). */ | |
5260325f | 538 | int waiting_termination = 0; /* Have displayed waiting close message. */ |
1e3b8b07 | 539 | u_int max_time_milliseconds; |
540 | u_int previous_stdout_buffer_bytes; | |
541 | u_int stdout_buffer_bytes; | |
5260325f | 542 | int type; |
543 | ||
544 | debug("Entering interactive session."); | |
545 | ||
546 | /* Initialize the SIGCHLD kludge. */ | |
5260325f | 547 | child_terminated = 0; |
42ad0eec | 548 | mysignal(SIGCHLD, sigchld_handler); |
5260325f | 549 | |
0bbbf2a4 | 550 | if (!use_privsep) { |
551 | signal(SIGTERM, sigterm_handler); | |
552 | signal(SIGINT, sigterm_handler); | |
553 | signal(SIGQUIT, sigterm_handler); | |
554 | } | |
555 | ||
5260325f | 556 | /* Initialize our global variables. */ |
557 | fdin = fdin_arg; | |
558 | fdout = fdout_arg; | |
559 | fderr = fderr_arg; | |
0e73cc53 | 560 | |
561 | /* nonblocking IO */ | |
562 | set_nonblock(fdin); | |
563 | set_nonblock(fdout); | |
ff873e98 | 564 | /* we don't have stderr for interactive terminal sessions, see below */ |
565 | if (fderr != -1) | |
566 | set_nonblock(fderr); | |
0e73cc53 | 567 | |
e68225b2 | 568 | if (!(datafellows & SSH_BUG_IGNOREMSG) && isatty(fdin)) |
569 | fdin_is_tty = 1; | |
570 | ||
5260325f | 571 | connection_in = packet_get_connection_in(); |
572 | connection_out = packet_get_connection_out(); | |
573 | ||
a10be357 | 574 | notify_setup(); |
575 | ||
5260325f | 576 | previous_stdout_buffer_bytes = 0; |
577 | ||
578 | /* Set approximate I/O buffer size. */ | |
579 | if (packet_is_interactive()) | |
580 | buffer_high = 4096; | |
581 | else | |
582 | buffer_high = 64 * 1024; | |
583 | ||
489aa2e9 | 584 | #if 0 |
5260325f | 585 | /* Initialize max_fd to the maximum of the known file descriptors. */ |
489aa2e9 | 586 | max_fd = MAX(connection_in, connection_out); |
587 | max_fd = MAX(max_fd, fdin); | |
588 | max_fd = MAX(max_fd, fdout); | |
39929cdb | 589 | if (fderr != -1) |
590 | max_fd = MAX(max_fd, fderr); | |
489aa2e9 | 591 | #endif |
5260325f | 592 | |
593 | /* Initialize Initialize buffers. */ | |
594 | buffer_init(&stdin_buffer); | |
595 | buffer_init(&stdout_buffer); | |
596 | buffer_init(&stderr_buffer); | |
597 | ||
aa3378df | 598 | /* |
599 | * If we have no separate fderr (which is the case when we have a pty | |
600 | * - there we cannot make difference between data sent to stdout and | |
601 | * stderr), indicate that we have seen an EOF from stderr. This way | |
7b9b0103 | 602 | * we don't need to check the descriptor everywhere. |
aa3378df | 603 | */ |
5260325f | 604 | if (fderr == -1) |
605 | fderr_eof = 1; | |
606 | ||
7368a6c8 | 607 | server_init_dispatch(); |
608 | ||
5260325f | 609 | /* Main loop of the server for the interactive session mode. */ |
610 | for (;;) { | |
5260325f | 611 | |
612 | /* Process buffered packets from the client. */ | |
613 | process_buffered_input_packets(); | |
614 | ||
aa3378df | 615 | /* |
616 | * If we have received eof, and there is no more pending | |
617 | * input data, cause a real eof by closing fdin. | |
618 | */ | |
5260325f | 619 | if (stdin_eof && fdin != -1 && buffer_len(&stdin_buffer) == 0) { |
7368a6c8 | 620 | if (fdin != fdout) |
5260325f | 621 | close(fdin); |
622 | else | |
623 | shutdown(fdin, SHUT_WR); /* We will no longer send. */ | |
5260325f | 624 | fdin = -1; |
625 | } | |
aa3378df | 626 | /* Make packets from buffered stderr data to send to the client. */ |
5260325f | 627 | make_packets_from_stderr_data(); |
628 | ||
aa3378df | 629 | /* |
630 | * Make packets from buffered stdout data to send to the | |
631 | * client. If there is very little to send, this arranges to | |
632 | * not send them now, but to wait a short while to see if we | |
633 | * are getting more data. This is necessary, as some systems | |
634 | * wake up readers from a pty after each separate character. | |
635 | */ | |
5260325f | 636 | max_time_milliseconds = 0; |
637 | stdout_buffer_bytes = buffer_len(&stdout_buffer); | |
638 | if (stdout_buffer_bytes != 0 && stdout_buffer_bytes < 256 && | |
639 | stdout_buffer_bytes != previous_stdout_buffer_bytes) { | |
640 | /* try again after a while */ | |
641 | max_time_milliseconds = 10; | |
642 | } else { | |
643 | /* Send it now. */ | |
644 | make_packets_from_stdout_data(); | |
645 | } | |
646 | previous_stdout_buffer_bytes = buffer_len(&stdout_buffer); | |
647 | ||
648 | /* Send channel data to the client. */ | |
649 | if (packet_not_very_much_data_to_write()) | |
650 | channel_output_poll(); | |
651 | ||
aa3378df | 652 | /* |
653 | * Bail out of the loop if the program has closed its output | |
654 | * descriptors, and we have no more data to send to the | |
655 | * client, and there is no pending buffered data. | |
656 | */ | |
7062c40f | 657 | if (fdout_eof && fderr_eof && !packet_have_data_to_write() && |
658 | buffer_len(&stdout_buffer) == 0 && buffer_len(&stderr_buffer) == 0) { | |
5260325f | 659 | if (!channel_still_open()) |
7368a6c8 | 660 | break; |
5260325f | 661 | if (!waiting_termination) { |
662 | const char *s = "Waiting for forwarded connections to terminate...\r\n"; | |
663 | char *cp; | |
664 | waiting_termination = 1; | |
665 | buffer_append(&stderr_buffer, s, strlen(s)); | |
666 | ||
667 | /* Display list of open channels. */ | |
668 | cp = channel_open_message(); | |
669 | buffer_append(&stderr_buffer, cp, strlen(cp)); | |
670 | xfree(cp); | |
671 | } | |
672 | } | |
489aa2e9 | 673 | max_fd = MAX(connection_in, connection_out); |
674 | max_fd = MAX(max_fd, fdin); | |
675 | max_fd = MAX(max_fd, fdout); | |
676 | max_fd = MAX(max_fd, fderr); | |
a10be357 | 677 | max_fd = MAX(max_fd, notify_pipe[0]); |
489aa2e9 | 678 | |
5260325f | 679 | /* Sleep in select() until we can do something. */ |
39929cdb | 680 | wait_until_can_do_something(&readset, &writeset, &max_fd, |
489aa2e9 | 681 | &nalloc, max_time_milliseconds); |
5260325f | 682 | |
0bbbf2a4 | 683 | if (received_sigterm) { |
684 | logit("Exiting on signal %d", received_sigterm); | |
685 | /* Clean up sessions, utmp, etc. */ | |
686 | cleanup_exit(255); | |
687 | } | |
688 | ||
5260325f | 689 | /* Process any channel events. */ |
39929cdb | 690 | channel_after_select(readset, writeset); |
5260325f | 691 | |
692 | /* Process input from the client and from program stdout/stderr. */ | |
39929cdb | 693 | process_input(readset); |
5260325f | 694 | |
695 | /* Process output to the client and to program stdin. */ | |
39929cdb | 696 | process_output(writeset); |
8efc0c15 | 697 | } |
39929cdb | 698 | if (readset) |
699 | xfree(readset); | |
700 | if (writeset) | |
701 | xfree(writeset); | |
8efc0c15 | 702 | |
5260325f | 703 | /* Cleanup and termination code. */ |
8efc0c15 | 704 | |
5260325f | 705 | /* Wait until all output has been sent to the client. */ |
706 | drain_output(); | |
8efc0c15 | 707 | |
5260325f | 708 | debug("End of interactive session; stdin %ld, stdout (read %ld, sent %ld), stderr %ld bytes.", |
184eed6a | 709 | stdin_bytes, fdout_bytes, stdout_bytes, stderr_bytes); |
8efc0c15 | 710 | |
5260325f | 711 | /* Free and clear the buffers. */ |
712 | buffer_free(&stdin_buffer); | |
713 | buffer_free(&stdout_buffer); | |
714 | buffer_free(&stderr_buffer); | |
8efc0c15 | 715 | |
5260325f | 716 | /* Close the file descriptors. */ |
717 | if (fdout != -1) | |
718 | close(fdout); | |
719 | fdout = -1; | |
720 | fdout_eof = 1; | |
721 | if (fderr != -1) | |
722 | close(fderr); | |
723 | fderr = -1; | |
724 | fderr_eof = 1; | |
725 | if (fdin != -1) | |
726 | close(fdin); | |
727 | fdin = -1; | |
728 | ||
d6746a0b | 729 | channel_free_all(); |
5260325f | 730 | |
5260325f | 731 | /* We no longer want our SIGCHLD handler to be called. */ |
42ad0eec | 732 | mysignal(SIGCHLD, SIG_DFL); |
5260325f | 733 | |
8c38e88b | 734 | while ((wait_pid = waitpid(-1, &wait_status, 0)) < 0) |
735 | if (errno != EINTR) | |
736 | packet_disconnect("wait: %.100s", strerror(errno)); | |
737 | if (wait_pid != pid) | |
c457707e | 738 | error("Strange, wait returned pid %ld, expected %ld", |
739 | (long)wait_pid, (long)pid); | |
c9130033 | 740 | |
5260325f | 741 | /* Check if it exited normally. */ |
742 | if (WIFEXITED(wait_status)) { | |
743 | /* Yes, normal exit. Get exit status and send it to the client. */ | |
744 | debug("Command exited with status %d.", WEXITSTATUS(wait_status)); | |
745 | packet_start(SSH_SMSG_EXITSTATUS); | |
746 | packet_put_int(WEXITSTATUS(wait_status)); | |
747 | packet_send(); | |
748 | packet_write_wait(); | |
749 | ||
aa3378df | 750 | /* |
751 | * Wait for exit confirmation. Note that there might be | |
752 | * other packets coming before it; however, the program has | |
753 | * already died so we just ignore them. The client is | |
754 | * supposed to respond with the confirmation when it receives | |
755 | * the exit status. | |
756 | */ | |
5260325f | 757 | do { |
54a5250f | 758 | type = packet_read(); |
5260325f | 759 | } |
760 | while (type != SSH_CMSG_EXIT_CONFIRMATION); | |
761 | ||
762 | debug("Received exit confirmation."); | |
763 | return; | |
764 | } | |
765 | /* Check if the program terminated due to a signal. */ | |
766 | if (WIFSIGNALED(wait_status)) | |
767 | packet_disconnect("Command terminated on signal %d.", | |
768 | WTERMSIG(wait_status)); | |
769 | ||
770 | /* Some weird exit cause. Just exit. */ | |
771 | packet_disconnect("wait returned status %04x.", wait_status); | |
772 | /* NOTREACHED */ | |
773 | } | |
7368a6c8 | 774 | |
418e724c | 775 | static void |
776 | collect_children(void) | |
777 | { | |
778 | pid_t pid; | |
779 | sigset_t oset, nset; | |
780 | int status; | |
781 | ||
782 | /* block SIGCHLD while we check for dead children */ | |
783 | sigemptyset(&nset); | |
784 | sigaddset(&nset, SIGCHLD); | |
785 | sigprocmask(SIG_BLOCK, &nset, &oset); | |
786 | if (child_terminated) { | |
140000b4 | 787 | debug("Received SIGCHLD."); |
8c38e88b | 788 | while ((pid = waitpid(-1, &status, WNOHANG)) > 0 || |
789 | (pid < 0 && errno == EINTR)) | |
790 | if (pid > 0) | |
791 | session_close_by_pid(pid, status); | |
418e724c | 792 | child_terminated = 0; |
793 | } | |
794 | sigprocmask(SIG_SETMASK, &oset, NULL); | |
795 | } | |
796 | ||
6ae2364d | 797 | void |
57156994 | 798 | server_loop2(Authctxt *authctxt) |
e78a59f5 | 799 | { |
39929cdb | 800 | fd_set *readset = NULL, *writeset = NULL; |
418e724c | 801 | int rekeying = 0, max_fd, nalloc = 0; |
e78a59f5 | 802 | |
803 | debug("Entering interactive session for SSH2."); | |
804 | ||
c9130033 | 805 | mysignal(SIGCHLD, sigchld_handler); |
e78a59f5 | 806 | child_terminated = 0; |
807 | connection_in = packet_get_connection_in(); | |
808 | connection_out = packet_get_connection_out(); | |
39929cdb | 809 | |
0bbbf2a4 | 810 | if (!use_privsep) { |
811 | signal(SIGTERM, sigterm_handler); | |
812 | signal(SIGINT, sigterm_handler); | |
813 | signal(SIGQUIT, sigterm_handler); | |
814 | } | |
815 | ||
a10be357 | 816 | notify_setup(); |
817 | ||
39929cdb | 818 | max_fd = MAX(connection_in, connection_out); |
a10be357 | 819 | max_fd = MAX(max_fd, notify_pipe[0]); |
820 | ||
e78a59f5 | 821 | server_init_dispatch(); |
822 | ||
823 | for (;;) { | |
824 | process_buffered_input_packets(); | |
bbb4cc1b | 825 | |
cd332296 | 826 | rekeying = (xxx_kex != NULL && !xxx_kex->done); |
bbb4cc1b | 827 | |
bbb4cc1b | 828 | if (!rekeying && packet_not_very_much_data_to_write()) |
e78a59f5 | 829 | channel_output_poll(); |
bbb4cc1b | 830 | wait_until_can_do_something(&readset, &writeset, &max_fd, |
489aa2e9 | 831 | &nalloc, 0); |
d5f24f94 | 832 | |
0bbbf2a4 | 833 | if (received_sigterm) { |
834 | logit("Exiting on signal %d", received_sigterm); | |
835 | /* Clean up sessions, utmp, etc. */ | |
836 | cleanup_exit(255); | |
837 | } | |
838 | ||
418e724c | 839 | collect_children(); |
ffd7b36b | 840 | if (!rekeying) { |
bbb4cc1b | 841 | channel_after_select(readset, writeset); |
ffd7b36b | 842 | if (packet_need_rekeying()) { |
843 | debug("need rekeying"); | |
844 | xxx_kex->done = 0; | |
845 | kex_send_kexinit(xxx_kex); | |
846 | } | |
847 | } | |
39929cdb | 848 | process_input(readset); |
cc94bd38 | 849 | if (connection_closed) |
850 | break; | |
39929cdb | 851 | process_output(writeset); |
e78a59f5 | 852 | } |
418e724c | 853 | collect_children(); |
854 | ||
39929cdb | 855 | if (readset) |
856 | xfree(readset); | |
857 | if (writeset) | |
858 | xfree(writeset); | |
859 | ||
d5f24f94 | 860 | /* free all channels, no more reads and writes */ |
861 | channel_free_all(); | |
5b5d170c | 862 | |
418e724c | 863 | /* free remaining sessions, e.g. remove wtmp entries */ |
1853d1ef | 864 | session_destroy_all(NULL); |
e78a59f5 | 865 | } |
866 | ||
396c147e | 867 | static void |
95ae2076 | 868 | server_input_keep_alive(int type, u_int32_t seq, void *ctxt) |
3ffc6336 | 869 | { |
95ae2076 | 870 | debug("Got %d/%u for keepalive", type, seq); |
184eed6a | 871 | /* |
39aefe7b | 872 | * reset timeout, since we got a sane answer from the client. |
3ffc6336 | 873 | * even if this was generated by something other than |
874 | * the bogus CHANNEL_REQUEST we send for keepalives. | |
875 | */ | |
184eed6a | 876 | client_alive_timeouts = 0; |
3ffc6336 | 877 | } |
878 | ||
396c147e | 879 | static void |
7819b5c3 | 880 | server_input_stdin_data(int type, u_int32_t seq, void *ctxt) |
7368a6c8 | 881 | { |
882 | char *data; | |
1e3b8b07 | 883 | u_int data_len; |
7368a6c8 | 884 | |
885 | /* Stdin data from the client. Append it to the buffer. */ | |
886 | /* Ignore any data if the client has closed stdin. */ | |
887 | if (fdin == -1) | |
888 | return; | |
889 | data = packet_get_string(&data_len); | |
95500969 | 890 | packet_check_eom(); |
7368a6c8 | 891 | buffer_append(&stdin_buffer, data, data_len); |
892 | memset(data, 0, data_len); | |
893 | xfree(data); | |
894 | } | |
895 | ||
396c147e | 896 | static void |
7819b5c3 | 897 | server_input_eof(int type, u_int32_t seq, void *ctxt) |
7368a6c8 | 898 | { |
899 | /* | |
900 | * Eof from the client. The stdin descriptor to the | |
901 | * program will be closed when all buffered data has | |
902 | * drained. | |
903 | */ | |
904 | debug("EOF received for stdin."); | |
95500969 | 905 | packet_check_eom(); |
7368a6c8 | 906 | stdin_eof = 1; |
907 | } | |
908 | ||
396c147e | 909 | static void |
7819b5c3 | 910 | server_input_window_size(int type, u_int32_t seq, void *ctxt) |
7368a6c8 | 911 | { |
148de80c | 912 | u_int row = packet_get_int(); |
913 | u_int col = packet_get_int(); | |
914 | u_int xpixel = packet_get_int(); | |
915 | u_int ypixel = packet_get_int(); | |
7368a6c8 | 916 | |
917 | debug("Window change received."); | |
95500969 | 918 | packet_check_eom(); |
7368a6c8 | 919 | if (fdin != -1) |
920 | pty_change_window_size(fdin, row, col, xpixel, ypixel); | |
921 | } | |
922 | ||
396c147e | 923 | static Channel * |
43f7a4b8 | 924 | server_request_direct_tcpip(void) |
e78a59f5 | 925 | { |
719fc62f | 926 | Channel *c; |
927 | int sock; | |
6ae2364d | 928 | char *target, *originator; |
929 | int target_port, originator_port; | |
e78a59f5 | 930 | |
6ae2364d | 931 | target = packet_get_string(NULL); |
932 | target_port = packet_get_int(); | |
e78a59f5 | 933 | originator = packet_get_string(NULL); |
934 | originator_port = packet_get_int(); | |
95500969 | 935 | packet_check_eom(); |
71276795 | 936 | |
fa08c86b | 937 | debug("server_request_direct_tcpip: originator %s port %d, target %s port %d", |
4e2e5cfd | 938 | originator, originator_port, target, target_port); |
38c295d6 | 939 | |
e78a59f5 | 940 | /* XXX check permission */ |
6ae2364d | 941 | sock = channel_connect_to(target, target_port); |
942 | xfree(target); | |
e78a59f5 | 943 | xfree(originator); |
944 | if (sock < 0) | |
fa08c86b | 945 | return NULL; |
43f7a4b8 | 946 | c = channel_new("direct-tcpip", SSH_CHANNEL_CONNECTING, |
bcbf86ec | 947 | sock, sock, -1, CHAN_TCP_WINDOW_DEFAULT, |
0d942eff | 948 | CHAN_TCP_PACKET_DEFAULT, 0, "direct-tcpip", 1); |
719fc62f | 949 | return c; |
fa08c86b | 950 | } |
951 | ||
d20f3c9e | 952 | static Channel * |
953 | server_request_tun(void) | |
954 | { | |
955 | Channel *c = NULL; | |
a4f24bf8 | 956 | int mode, tun; |
957 | int sock; | |
d20f3c9e | 958 | |
a4f24bf8 | 959 | mode = packet_get_int(); |
960 | switch (mode) { | |
961 | case SSH_TUNMODE_POINTOPOINT: | |
962 | case SSH_TUNMODE_ETHERNET: | |
963 | break; | |
964 | default: | |
965 | packet_send_debug("Unsupported tunnel device mode."); | |
966 | return NULL; | |
967 | } | |
968 | if ((options.permit_tun & mode) == 0) { | |
969 | packet_send_debug("Server has rejected tunnel device " | |
970 | "forwarding"); | |
d20f3c9e | 971 | return NULL; |
972 | } | |
973 | ||
974 | tun = packet_get_int(); | |
a2b1748a | 975 | if (forced_tun_device != -1) { |
3efa8ea9 | 976 | if (tun != SSH_TUNID_ANY && forced_tun_device != tun) |
d20f3c9e | 977 | goto done; |
978 | tun = forced_tun_device; | |
979 | } | |
a4f24bf8 | 980 | sock = tun_open(tun, mode); |
d20f3c9e | 981 | if (sock < 0) |
982 | goto done; | |
983 | c = channel_new("tun", SSH_CHANNEL_OPEN, sock, sock, -1, | |
984 | CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, "tun", 1); | |
985 | c->datagram = 1; | |
e914f53a | 986 | #if defined(SSH_TUN_FILTER) |
987 | if (mode == SSH_TUNMODE_POINTOPOINT) | |
988 | channel_register_filter(c->self, sys_tun_infilter, | |
989 | sys_tun_outfilter); | |
990 | #endif | |
d20f3c9e | 991 | |
992 | done: | |
993 | if (c == NULL) | |
994 | packet_send_debug("Failed to open the tunnel device."); | |
995 | return c; | |
996 | } | |
997 | ||
396c147e | 998 | static Channel * |
43f7a4b8 | 999 | server_request_session(void) |
fa08c86b | 1000 | { |
719fc62f | 1001 | Channel *c; |
fa08c86b | 1002 | |
1003 | debug("input_session_request"); | |
95500969 | 1004 | packet_check_eom(); |
fa08c86b | 1005 | /* |
1006 | * A server session has no fd to read or write until a | |
1007 | * CHANNEL_REQUEST for a shell is made, so we set the type to | |
1008 | * SSH_CHANNEL_LARVAL. Additionally, a callback for handling all | |
1009 | * CHANNEL_REQUEST messages is registered. | |
1010 | */ | |
43f7a4b8 | 1011 | c = channel_new("session", SSH_CHANNEL_LARVAL, |
719fc62f | 1012 | -1, -1, -1, /*window size*/0, CHAN_SES_PACKET_DEFAULT, |
0d942eff | 1013 | 0, "server-session", 1); |
2362db19 | 1014 | if (session_open(the_authctxt, c->self) != 1) { |
719fc62f | 1015 | debug("session open failed, free channel %d", c->self); |
1016 | channel_free(c); | |
1017 | return NULL; | |
fa08c86b | 1018 | } |
8cd0437d | 1019 | channel_register_cleanup(c->self, session_close_by_channel, 0); |
719fc62f | 1020 | return c; |
e78a59f5 | 1021 | } |
1022 | ||
396c147e | 1023 | static void |
7819b5c3 | 1024 | server_input_channel_open(int type, u_int32_t seq, void *ctxt) |
e78a59f5 | 1025 | { |
1026 | Channel *c = NULL; | |
1027 | char *ctype; | |
e78a59f5 | 1028 | int rchan; |
f91d9a89 | 1029 | u_int rmaxpack, rwindow, len; |
e78a59f5 | 1030 | |
1031 | ctype = packet_get_string(&len); | |
1032 | rchan = packet_get_int(); | |
1033 | rwindow = packet_get_int(); | |
1034 | rmaxpack = packet_get_int(); | |
1035 | ||
188adeb2 | 1036 | debug("server_input_channel_open: ctype %s rchan %d win %d max %d", |
e78a59f5 | 1037 | ctype, rchan, rwindow, rmaxpack); |
1038 | ||
1039 | if (strcmp(ctype, "session") == 0) { | |
43f7a4b8 | 1040 | c = server_request_session(); |
e78a59f5 | 1041 | } else if (strcmp(ctype, "direct-tcpip") == 0) { |
43f7a4b8 | 1042 | c = server_request_direct_tcpip(); |
d20f3c9e | 1043 | } else if (strcmp(ctype, "tun@openssh.com") == 0) { |
1044 | c = server_request_tun(); | |
e78a59f5 | 1045 | } |
1046 | if (c != NULL) { | |
fa08c86b | 1047 | debug("server_input_channel_open: confirm %s", ctype); |
e78a59f5 | 1048 | c->remote_id = rchan; |
1049 | c->remote_window = rwindow; | |
1050 | c->remote_maxpacket = rmaxpack; | |
d18e0850 | 1051 | if (c->type != SSH_CHANNEL_CONNECTING) { |
1052 | packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1053 | packet_put_int(c->remote_id); | |
1054 | packet_put_int(c->self); | |
1055 | packet_put_int(c->local_window); | |
1056 | packet_put_int(c->local_maxpacket); | |
1057 | packet_send(); | |
1058 | } | |
e78a59f5 | 1059 | } else { |
fa08c86b | 1060 | debug("server_input_channel_open: failure %s", ctype); |
e78a59f5 | 1061 | packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE); |
1062 | packet_put_int(rchan); | |
1063 | packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED); | |
fbe90f7b | 1064 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { |
d18e0850 | 1065 | packet_put_cstring("open failed"); |
fbe90f7b | 1066 | packet_put_cstring(""); |
1067 | } | |
e78a59f5 | 1068 | packet_send(); |
1069 | } | |
1070 | xfree(ctype); | |
1071 | } | |
1072 | ||
396c147e | 1073 | static void |
7819b5c3 | 1074 | server_input_global_request(int type, u_int32_t seq, void *ctxt) |
fa08c86b | 1075 | { |
1076 | char *rtype; | |
1077 | int want_reply; | |
1078 | int success = 0; | |
1079 | ||
1080 | rtype = packet_get_string(NULL); | |
1081 | want_reply = packet_get_char(); | |
1082 | debug("server_input_global_request: rtype %s want_reply %d", rtype, want_reply); | |
2b87da3b | 1083 | |
01794848 | 1084 | /* -R style forwarding */ |
fa08c86b | 1085 | if (strcmp(rtype, "tcpip-forward") == 0) { |
1086 | struct passwd *pw; | |
1087 | char *listen_address; | |
1088 | u_short listen_port; | |
1089 | ||
2362db19 | 1090 | pw = the_authctxt->pw; |
95077f48 | 1091 | if (pw == NULL || !the_authctxt->valid) |
fdaef11e | 1092 | fatal("server_input_global_request: no/invalid user"); |
b08a39ff | 1093 | listen_address = packet_get_string(NULL); |
fa08c86b | 1094 | listen_port = (u_short)packet_get_int(); |
1095 | debug("server_input_global_request: tcpip-forward listen %s port %d", | |
1096 | listen_address, listen_port); | |
1097 | ||
1098 | /* check permissions */ | |
1099 | if (!options.allow_tcp_forwarding || | |
e6f15ed1 | 1100 | no_port_forwarding_flag |
1101 | #ifndef NO_IPPORT_RESERVED_CONCEPT | |
1102 | || (listen_port < IPPORT_RESERVED && pw->pw_uid != 0) | |
1103 | #endif | |
98c044d0 | 1104 | ) { |
fa08c86b | 1105 | success = 0; |
1106 | packet_send_debug("Server has disabled port forwarding."); | |
1107 | } else { | |
1108 | /* Start listening on the port */ | |
5641aefa | 1109 | success = channel_setup_remote_fwd_listener( |
1110 | listen_address, listen_port, options.gateway_ports); | |
fa08c86b | 1111 | } |
1112 | xfree(listen_address); | |
d740ec16 | 1113 | } else if (strcmp(rtype, "cancel-tcpip-forward") == 0) { |
1114 | char *cancel_address; | |
1115 | u_short cancel_port; | |
1116 | ||
1117 | cancel_address = packet_get_string(NULL); | |
1118 | cancel_port = (u_short)packet_get_int(); | |
1119 | debug("%s: cancel-tcpip-forward addr %s port %d", __func__, | |
1120 | cancel_address, cancel_port); | |
1121 | ||
1122 | success = channel_cancel_rport_listener(cancel_address, | |
1123 | cancel_port); | |
4113a1d7 | 1124 | xfree(cancel_address); |
fa08c86b | 1125 | } |
1126 | if (want_reply) { | |
1127 | packet_start(success ? | |
1128 | SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE); | |
1129 | packet_send(); | |
1130 | packet_write_wait(); | |
1131 | } | |
1132 | xfree(rtype); | |
1133 | } | |
a7137f6b | 1134 | |
7899c98f | 1135 | static void |
1136 | server_input_channel_req(int type, u_int32_t seq, void *ctxt) | |
1137 | { | |
1138 | Channel *c; | |
1139 | int id, reply, success = 0; | |
1140 | char *rtype; | |
1141 | ||
1142 | id = packet_get_int(); | |
1143 | rtype = packet_get_string(NULL); | |
1144 | reply = packet_get_char(); | |
1145 | ||
1146 | debug("server_input_channel_req: channel %d request %s reply %d", | |
1147 | id, rtype, reply); | |
1148 | ||
1149 | if ((c = channel_lookup(id)) == NULL) | |
1150 | packet_disconnect("server_input_channel_req: " | |
1151 | "unknown channel %d", id); | |
1152 | if (c->type == SSH_CHANNEL_LARVAL || c->type == SSH_CHANNEL_OPEN) | |
1153 | success = session_input_channel_req(c, rtype); | |
1154 | if (reply) { | |
1155 | packet_start(success ? | |
1156 | SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE); | |
1157 | packet_put_int(c->remote_id); | |
1158 | packet_send(); | |
1159 | } | |
1160 | xfree(rtype); | |
1161 | } | |
fa08c86b | 1162 | |
396c147e | 1163 | static void |
5ca51e19 | 1164 | server_init_dispatch_20(void) |
e78a59f5 | 1165 | { |
1166 | debug("server_init_dispatch_20"); | |
1167 | dispatch_init(&dispatch_protocol_error); | |
1168 | dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose); | |
1169 | dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data); | |
1170 | dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof); | |
1171 | dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data); | |
1172 | dispatch_set(SSH2_MSG_CHANNEL_OPEN, &server_input_channel_open); | |
1173 | dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation); | |
1174 | dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure); | |
7899c98f | 1175 | dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &server_input_channel_req); |
e78a59f5 | 1176 | dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust); |
fa08c86b | 1177 | dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &server_input_global_request); |
3ffc6336 | 1178 | /* client_alive */ |
95ae2076 | 1179 | dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &server_input_keep_alive); |
1180 | dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &server_input_keep_alive); | |
1181 | dispatch_set(SSH2_MSG_REQUEST_FAILURE, &server_input_keep_alive); | |
7a37c112 | 1182 | /* rekeying */ |
1183 | dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit); | |
e78a59f5 | 1184 | } |
396c147e | 1185 | static void |
5ca51e19 | 1186 | server_init_dispatch_13(void) |
7368a6c8 | 1187 | { |
1188 | debug("server_init_dispatch_13"); | |
1189 | dispatch_init(NULL); | |
1190 | dispatch_set(SSH_CMSG_EOF, &server_input_eof); | |
1191 | dispatch_set(SSH_CMSG_STDIN_DATA, &server_input_stdin_data); | |
1192 | dispatch_set(SSH_CMSG_WINDOW_SIZE, &server_input_window_size); | |
1193 | dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close); | |
1194 | dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation); | |
1195 | dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data); | |
1196 | dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation); | |
1197 | dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure); | |
1198 | dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open); | |
1199 | } | |
396c147e | 1200 | static void |
5ca51e19 | 1201 | server_init_dispatch_15(void) |
7368a6c8 | 1202 | { |
1203 | server_init_dispatch_13(); | |
1204 | debug("server_init_dispatch_15"); | |
1205 | dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof); | |
1206 | dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_oclose); | |
1207 | } | |
396c147e | 1208 | static void |
5ca51e19 | 1209 | server_init_dispatch(void) |
7368a6c8 | 1210 | { |
e78a59f5 | 1211 | if (compat20) |
1212 | server_init_dispatch_20(); | |
1213 | else if (compat13) | |
7368a6c8 | 1214 | server_init_dispatch_13(); |
1215 | else | |
1216 | server_init_dispatch_15(); | |
1217 | } |