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b476adfa | 1 | /* $OpenBSD: serverloop.c,v 1.135 2006/03/25 18:30:55 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> | |
41 | #include <sys/wait.h> | |
1d3e026f | 42 | |
ada68823 | 43 | #include <signal.h> |
1d3e026f | 44 | #include <termios.h> |
a22aff1f | 45 | |
8efc0c15 | 46 | #include "xmalloc.h" |
8efc0c15 | 47 | #include "packet.h" |
48 | #include "buffer.h" | |
42f11eb2 | 49 | #include "log.h" |
8efc0c15 | 50 | #include "servconf.h" |
00e842d8 | 51 | #include "canohost.h" |
1729c161 | 52 | #include "sshpty.h" |
a5efa1bb | 53 | #include "channels.h" |
7368a6c8 | 54 | #include "compat.h" |
42f11eb2 | 55 | #include "ssh1.h" |
e78a59f5 | 56 | #include "ssh2.h" |
59c97189 | 57 | #include "auth.h" |
e78a59f5 | 58 | #include "session.h" |
7368a6c8 | 59 | #include "dispatch.h" |
38c295d6 | 60 | #include "auth-options.h" |
42f11eb2 | 61 | #include "serverloop.h" |
62 | #include "misc.h" | |
7a37c112 | 63 | #include "kex.h" |
8efc0c15 | 64 | |
33de75a3 | 65 | extern ServerOptions options; |
66 | ||
7a37c112 | 67 | /* XXX */ |
68 | extern Kex *xxx_kex; | |
2362db19 | 69 | extern Authctxt *the_authctxt; |
0bbbf2a4 | 70 | extern int use_privsep; |
7a37c112 | 71 | |
8efc0c15 | 72 | static Buffer stdin_buffer; /* Buffer for stdin data. */ |
73 | static Buffer stdout_buffer; /* Buffer for stdout data. */ | |
74 | static Buffer stderr_buffer; /* Buffer for stderr data. */ | |
75 | static int fdin; /* Descriptor for stdin (for writing) */ | |
76 | static int fdout; /* Descriptor for stdout (for reading); | |
77 | May be same number as fdin. */ | |
78 | static int fderr; /* Descriptor for stderr. May be -1. */ | |
79 | static long stdin_bytes = 0; /* Number of bytes written to stdin. */ | |
80 | static long stdout_bytes = 0; /* Number of stdout bytes sent to client. */ | |
81 | static long stderr_bytes = 0; /* Number of stderr bytes sent to client. */ | |
82 | static long fdout_bytes = 0; /* Number of stdout bytes read from program. */ | |
83 | static int stdin_eof = 0; /* EOF message received from client. */ | |
84 | static int fdout_eof = 0; /* EOF encountered reading from fdout. */ | |
85 | static int fderr_eof = 0; /* EOF encountered readung from fderr. */ | |
e68225b2 | 86 | static int fdin_is_tty = 0; /* fdin points to a tty. */ |
8efc0c15 | 87 | static int connection_in; /* Connection to client (input). */ |
88 | static int connection_out; /* Connection to client (output). */ | |
cc94bd38 | 89 | static int connection_closed = 0; /* Connection to client closed. */ |
90 | static u_int buffer_high; /* "Soft" max buffer size. */ | |
72176c0e | 91 | static int client_alive_timeouts = 0; |
8efc0c15 | 92 | |
aa3378df | 93 | /* |
94 | * This SIGCHLD kludge is used to detect when the child exits. The server | |
95 | * will exit after that, as soon as forwarded connections have terminated. | |
96 | */ | |
396c147e | 97 | |
7a934d1b | 98 | static volatile sig_atomic_t child_terminated = 0; /* The child has terminated. */ |
8efc0c15 | 99 | |
0bbbf2a4 | 100 | /* Cleanup on signals (!use_privsep case only) */ |
101 | static volatile sig_atomic_t received_sigterm = 0; | |
102 | ||
396c147e | 103 | /* prototypes */ |
104 | static void server_init_dispatch(void); | |
7368a6c8 | 105 | |
a10be357 | 106 | /* |
107 | * we write to this pipe if a SIGCHLD is caught in order to avoid | |
108 | * the race between select() and child_terminated | |
109 | */ | |
110 | static int notify_pipe[2]; | |
111 | static void | |
112 | notify_setup(void) | |
113 | { | |
114 | if (pipe(notify_pipe) < 0) { | |
115 | error("pipe(notify_pipe) failed %s", strerror(errno)); | |
116 | } else if ((fcntl(notify_pipe[0], F_SETFD, 1) == -1) || | |
117 | (fcntl(notify_pipe[1], F_SETFD, 1) == -1)) { | |
118 | error("fcntl(notify_pipe, F_SETFD) failed %s", strerror(errno)); | |
119 | close(notify_pipe[0]); | |
120 | close(notify_pipe[1]); | |
121 | } else { | |
122 | set_nonblock(notify_pipe[0]); | |
123 | set_nonblock(notify_pipe[1]); | |
124 | return; | |
125 | } | |
126 | notify_pipe[0] = -1; /* read end */ | |
127 | notify_pipe[1] = -1; /* write end */ | |
128 | } | |
129 | static void | |
130 | notify_parent(void) | |
131 | { | |
132 | if (notify_pipe[1] != -1) | |
133 | write(notify_pipe[1], "", 1); | |
134 | } | |
135 | static void | |
136 | notify_prepare(fd_set *readset) | |
137 | { | |
138 | if (notify_pipe[0] != -1) | |
139 | FD_SET(notify_pipe[0], readset); | |
140 | } | |
141 | static void | |
142 | notify_done(fd_set *readset) | |
143 | { | |
144 | char c; | |
145 | ||
146 | if (notify_pipe[0] != -1 && FD_ISSET(notify_pipe[0], readset)) | |
147 | while (read(notify_pipe[0], &c, 1) != -1) | |
148 | debug2("notify_done: reading"); | |
149 | } | |
150 | ||
3efa8ea9 | 151 | /*ARGSUSED*/ |
396c147e | 152 | static void |
5260325f | 153 | sigchld_handler(int sig) |
e78a59f5 | 154 | { |
155 | int save_errno = errno; | |
e78a59f5 | 156 | child_terminated = 1; |
ef51930f | 157 | #ifndef _UNICOS |
c9130033 | 158 | mysignal(SIGCHLD, sigchld_handler); |
ef51930f | 159 | #endif |
a10be357 | 160 | notify_parent(); |
e78a59f5 | 161 | errno = save_errno; |
162 | } | |
8efc0c15 | 163 | |
3efa8ea9 | 164 | /*ARGSUSED*/ |
0bbbf2a4 | 165 | static void |
166 | sigterm_handler(int sig) | |
167 | { | |
168 | received_sigterm = sig; | |
169 | } | |
170 | ||
5260325f | 171 | /* |
172 | * Make packets from buffered stderr data, and buffer it for sending | |
173 | * to the client. | |
174 | */ | |
396c147e | 175 | static void |
5ca51e19 | 176 | make_packets_from_stderr_data(void) |
8efc0c15 | 177 | { |
a27002e5 | 178 | u_int len; |
5260325f | 179 | |
180 | /* Send buffered stderr data to the client. */ | |
181 | while (buffer_len(&stderr_buffer) > 0 && | |
a408af76 | 182 | packet_not_very_much_data_to_write()) { |
5260325f | 183 | len = buffer_len(&stderr_buffer); |
184 | if (packet_is_interactive()) { | |
185 | if (len > 512) | |
186 | len = 512; | |
187 | } else { | |
188 | /* Keep the packets at reasonable size. */ | |
189 | if (len > packet_get_maxsize()) | |
190 | len = packet_get_maxsize(); | |
191 | } | |
192 | packet_start(SSH_SMSG_STDERR_DATA); | |
193 | packet_put_string(buffer_ptr(&stderr_buffer), len); | |
194 | packet_send(); | |
195 | buffer_consume(&stderr_buffer, len); | |
196 | stderr_bytes += len; | |
8efc0c15 | 197 | } |
8efc0c15 | 198 | } |
199 | ||
5260325f | 200 | /* |
201 | * Make packets from buffered stdout data, and buffer it for sending to the | |
202 | * client. | |
203 | */ | |
396c147e | 204 | static void |
5ca51e19 | 205 | make_packets_from_stdout_data(void) |
8efc0c15 | 206 | { |
a27002e5 | 207 | u_int len; |
5260325f | 208 | |
209 | /* Send buffered stdout data to the client. */ | |
210 | while (buffer_len(&stdout_buffer) > 0 && | |
a408af76 | 211 | packet_not_very_much_data_to_write()) { |
5260325f | 212 | len = buffer_len(&stdout_buffer); |
213 | if (packet_is_interactive()) { | |
214 | if (len > 512) | |
215 | len = 512; | |
216 | } else { | |
217 | /* Keep the packets at reasonable size. */ | |
218 | if (len > packet_get_maxsize()) | |
2b87da3b | 219 | len = packet_get_maxsize(); |
5260325f | 220 | } |
221 | packet_start(SSH_SMSG_STDOUT_DATA); | |
222 | packet_put_string(buffer_ptr(&stdout_buffer), len); | |
223 | packet_send(); | |
224 | buffer_consume(&stdout_buffer, len); | |
225 | stdout_bytes += len; | |
8efc0c15 | 226 | } |
8efc0c15 | 227 | } |
228 | ||
72176c0e | 229 | static void |
230 | client_alive_check(void) | |
231 | { | |
95ae2076 | 232 | int channel_id; |
99416ceb | 233 | |
72176c0e | 234 | /* timeout, check to see how many we have had */ |
235 | if (++client_alive_timeouts > options.client_alive_count_max) | |
236 | packet_disconnect("Timeout, your session not responding."); | |
237 | ||
72176c0e | 238 | /* |
95ae2076 | 239 | * send a bogus global/channel request with "wantreply", |
72176c0e | 240 | * we should get back a failure |
241 | */ | |
95ae2076 | 242 | if ((channel_id = channel_find_open()) == -1) { |
243 | packet_start(SSH2_MSG_GLOBAL_REQUEST); | |
244 | packet_put_cstring("keepalive@openssh.com"); | |
245 | packet_put_char(1); /* boolean: want reply */ | |
246 | } else { | |
247 | channel_request_start(channel_id, "keepalive@openssh.com", 1); | |
248 | } | |
72176c0e | 249 | packet_send(); |
250 | } | |
251 | ||
5260325f | 252 | /* |
253 | * Sleep in select() until we can do something. This will initialize the | |
254 | * select masks. Upon return, the masks will indicate which descriptors | |
255 | * have data or can accept data. Optionally, a maximum time can be specified | |
256 | * for the duration of the wait (0 = infinite). | |
257 | */ | |
396c147e | 258 | static void |
39929cdb | 259 | wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp, int *maxfdp, |
9a995072 | 260 | u_int *nallocp, u_int max_time_milliseconds) |
8efc0c15 | 261 | { |
5260325f | 262 | struct timeval tv, *tvp; |
263 | int ret; | |
3ffc6336 | 264 | int client_alive_scheduled = 0; |
265 | ||
266 | /* | |
184eed6a | 267 | * if using client_alive, set the max timeout accordingly, |
3ffc6336 | 268 | * and indicate that this particular timeout was for client |
269 | * alive by setting the client_alive_scheduled flag. | |
270 | * | |
271 | * this could be randomized somewhat to make traffic | |
184eed6a | 272 | * analysis more difficult, but we're not doing it yet. |
3ffc6336 | 273 | */ |
2c5b1791 | 274 | if (compat20 && |
275 | max_time_milliseconds == 0 && options.client_alive_interval) { | |
39aefe7b | 276 | client_alive_scheduled = 1; |
3ffc6336 | 277 | max_time_milliseconds = options.client_alive_interval * 1000; |
2c5b1791 | 278 | } |
8efc0c15 | 279 | |
39929cdb | 280 | /* Allocate and update select() masks for channel descriptors. */ |
489aa2e9 | 281 | channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, 0); |
5260325f | 282 | |
e78a59f5 | 283 | if (compat20) { |
0c139bd1 | 284 | #if 0 |
1d1ffb87 | 285 | /* wrong: bad condition XXX */ |
e78a59f5 | 286 | if (channel_not_very_much_buffered_data()) |
0c139bd1 | 287 | #endif |
288 | FD_SET(connection_in, *readsetp); | |
e78a59f5 | 289 | } else { |
71276795 | 290 | /* |
291 | * Read packets from the client unless we have too much | |
292 | * buffered stdin or channel data. | |
293 | */ | |
294 | if (buffer_len(&stdin_buffer) < buffer_high && | |
e78a59f5 | 295 | channel_not_very_much_buffered_data()) |
39929cdb | 296 | FD_SET(connection_in, *readsetp); |
71276795 | 297 | /* |
298 | * If there is not too much data already buffered going to | |
299 | * the client, try to get some more data from the program. | |
300 | */ | |
301 | if (packet_not_very_much_data_to_write()) { | |
302 | if (!fdout_eof) | |
39929cdb | 303 | FD_SET(fdout, *readsetp); |
71276795 | 304 | if (!fderr_eof) |
39929cdb | 305 | FD_SET(fderr, *readsetp); |
71276795 | 306 | } |
307 | /* | |
308 | * If we have buffered data, try to write some of that data | |
309 | * to the program. | |
310 | */ | |
311 | if (fdin != -1 && buffer_len(&stdin_buffer) > 0) | |
39929cdb | 312 | FD_SET(fdin, *writesetp); |
e78a59f5 | 313 | } |
a10be357 | 314 | notify_prepare(*readsetp); |
5260325f | 315 | |
aa3378df | 316 | /* |
317 | * If we have buffered packet data going to the client, mark that | |
318 | * descriptor. | |
319 | */ | |
5260325f | 320 | if (packet_have_data_to_write()) |
39929cdb | 321 | FD_SET(connection_out, *writesetp); |
5260325f | 322 | |
aa3378df | 323 | /* |
324 | * If child has terminated and there is enough buffer space to read | |
325 | * from it, then read as much as is available and exit. | |
326 | */ | |
5260325f | 327 | if (child_terminated && packet_not_very_much_data_to_write()) |
3ffc6336 | 328 | if (max_time_milliseconds == 0 || client_alive_scheduled) |
5260325f | 329 | max_time_milliseconds = 100; |
330 | ||
331 | if (max_time_milliseconds == 0) | |
332 | tvp = NULL; | |
333 | else { | |
334 | tv.tv_sec = max_time_milliseconds / 1000; | |
335 | tv.tv_usec = 1000 * (max_time_milliseconds % 1000); | |
336 | tvp = &tv; | |
337 | } | |
8efc0c15 | 338 | |
5260325f | 339 | /* Wait for something to happen, or the timeout to expire. */ |
39929cdb | 340 | ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp); |
8efc0c15 | 341 | |
3ffc6336 | 342 | if (ret == -1) { |
b3ad8fe6 | 343 | memset(*readsetp, 0, *nallocp); |
344 | memset(*writesetp, 0, *nallocp); | |
5260325f | 345 | if (errno != EINTR) |
346 | error("select: %.100s", strerror(errno)); | |
418e724c | 347 | } else if (ret == 0 && client_alive_scheduled) |
72176c0e | 348 | client_alive_check(); |
a10be357 | 349 | |
350 | notify_done(*readsetp); | |
8efc0c15 | 351 | } |
352 | ||
5260325f | 353 | /* |
354 | * Processes input from the client and the program. Input data is stored | |
355 | * in buffers and processed later. | |
356 | */ | |
396c147e | 357 | static void |
b476adfa | 358 | process_input(fd_set *readset) |
5260325f | 359 | { |
360 | int len; | |
361 | char buf[16384]; | |
362 | ||
363 | /* Read and buffer any input data from the client. */ | |
364 | if (FD_ISSET(connection_in, readset)) { | |
365 | len = read(connection_in, buf, sizeof(buf)); | |
366 | if (len == 0) { | |
00e842d8 | 367 | verbose("Connection closed by %.100s", |
368 | get_remote_ipaddr()); | |
cc94bd38 | 369 | connection_closed = 1; |
370 | if (compat20) | |
371 | return; | |
2362db19 | 372 | cleanup_exit(255); |
0e73cc53 | 373 | } else if (len < 0) { |
374 | if (errno != EINTR && errno != EAGAIN) { | |
00e842d8 | 375 | verbose("Read error from remote host " |
376 | "%.100s: %.100s", | |
377 | get_remote_ipaddr(), strerror(errno)); | |
2362db19 | 378 | cleanup_exit(255); |
0e73cc53 | 379 | } |
380 | } else { | |
381 | /* Buffer any received data. */ | |
382 | packet_process_incoming(buf, len); | |
5260325f | 383 | } |
5260325f | 384 | } |
e78a59f5 | 385 | if (compat20) |
386 | return; | |
387 | ||
5260325f | 388 | /* Read and buffer any available stdout data from the program. */ |
389 | if (!fdout_eof && FD_ISSET(fdout, readset)) { | |
ea8c44d9 | 390 | errno = 0; |
5260325f | 391 | len = read(fdout, buf, sizeof(buf)); |
0e73cc53 | 392 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) { |
393 | /* do nothing */ | |
24a87055 | 394 | #ifndef PTY_ZEROREAD |
0e73cc53 | 395 | } else if (len <= 0) { |
ea8c44d9 | 396 | #else |
397 | } else if (len < 0 || (len == 0 && errno != 0)) { | |
398 | #endif | |
5260325f | 399 | fdout_eof = 1; |
0e73cc53 | 400 | } else { |
5260325f | 401 | buffer_append(&stdout_buffer, buf, len); |
402 | fdout_bytes += len; | |
403 | } | |
404 | } | |
405 | /* Read and buffer any available stderr data from the program. */ | |
406 | if (!fderr_eof && FD_ISSET(fderr, readset)) { | |
ea8c44d9 | 407 | errno = 0; |
5260325f | 408 | len = read(fderr, buf, sizeof(buf)); |
0e73cc53 | 409 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) { |
410 | /* do nothing */ | |
24a87055 | 411 | #ifndef PTY_ZEROREAD |
0e73cc53 | 412 | } else if (len <= 0) { |
ea8c44d9 | 413 | #else |
414 | } else if (len < 0 || (len == 0 && errno != 0)) { | |
415 | #endif | |
5260325f | 416 | fderr_eof = 1; |
0e73cc53 | 417 | } else { |
5260325f | 418 | buffer_append(&stderr_buffer, buf, len); |
0e73cc53 | 419 | } |
5260325f | 420 | } |
421 | } | |
8efc0c15 | 422 | |
5260325f | 423 | /* |
424 | * Sends data from internal buffers to client program stdin. | |
425 | */ | |
396c147e | 426 | static void |
b476adfa | 427 | process_output(fd_set *writeset) |
8efc0c15 | 428 | { |
4ef922e3 | 429 | struct termios tio; |
780a9951 | 430 | u_char *data; |
431 | u_int dlen; | |
5260325f | 432 | int len; |
433 | ||
434 | /* Write buffered data to program stdin. */ | |
e78a59f5 | 435 | if (!compat20 && fdin != -1 && FD_ISSET(fdin, writeset)) { |
780a9951 | 436 | data = buffer_ptr(&stdin_buffer); |
437 | dlen = buffer_len(&stdin_buffer); | |
438 | len = write(fdin, data, dlen); | |
0e73cc53 | 439 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) { |
440 | /* do nothing */ | |
441 | } else if (len <= 0) { | |
7368a6c8 | 442 | if (fdin != fdout) |
5260325f | 443 | close(fdin); |
444 | else | |
445 | shutdown(fdin, SHUT_WR); /* We will no longer send. */ | |
5260325f | 446 | fdin = -1; |
447 | } else { | |
4ef922e3 | 448 | /* Successful write. */ |
780a9951 | 449 | if (fdin_is_tty && dlen >= 1 && data[0] != '\r' && |
450 | tcgetattr(fdin, &tio) == 0 && | |
0ae4fe1d | 451 | !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) { |
62da27dd | 452 | /* |
453 | * Simulate echo to reduce the impact of | |
454 | * traffic analysis | |
455 | */ | |
95ce5599 | 456 | packet_send_ignore(len); |
4ef922e3 | 457 | packet_send(); |
458 | } | |
459 | /* Consume the data from the buffer. */ | |
5260325f | 460 | buffer_consume(&stdin_buffer, len); |
461 | /* Update the count of bytes written to the program. */ | |
462 | stdin_bytes += len; | |
463 | } | |
8efc0c15 | 464 | } |
5260325f | 465 | /* Send any buffered packet data to the client. */ |
466 | if (FD_ISSET(connection_out, writeset)) | |
467 | packet_write_poll(); | |
8efc0c15 | 468 | } |
469 | ||
5260325f | 470 | /* |
471 | * Wait until all buffered output has been sent to the client. | |
472 | * This is used when the program terminates. | |
473 | */ | |
396c147e | 474 | static void |
5ca51e19 | 475 | drain_output(void) |
8efc0c15 | 476 | { |
5260325f | 477 | /* Send any buffered stdout data to the client. */ |
478 | if (buffer_len(&stdout_buffer) > 0) { | |
479 | packet_start(SSH_SMSG_STDOUT_DATA); | |
480 | packet_put_string(buffer_ptr(&stdout_buffer), | |
481 | buffer_len(&stdout_buffer)); | |
482 | packet_send(); | |
483 | /* Update the count of sent bytes. */ | |
484 | stdout_bytes += buffer_len(&stdout_buffer); | |
485 | } | |
486 | /* Send any buffered stderr data to the client. */ | |
487 | if (buffer_len(&stderr_buffer) > 0) { | |
488 | packet_start(SSH_SMSG_STDERR_DATA); | |
489 | packet_put_string(buffer_ptr(&stderr_buffer), | |
490 | buffer_len(&stderr_buffer)); | |
491 | packet_send(); | |
492 | /* Update the count of sent bytes. */ | |
493 | stderr_bytes += buffer_len(&stderr_buffer); | |
494 | } | |
495 | /* Wait until all buffered data has been written to the client. */ | |
496 | packet_write_wait(); | |
8efc0c15 | 497 | } |
498 | ||
396c147e | 499 | static void |
5ca51e19 | 500 | process_buffered_input_packets(void) |
7368a6c8 | 501 | { |
7a37c112 | 502 | dispatch_run(DISPATCH_NONBLOCK, NULL, compat20 ? xxx_kex : NULL); |
7368a6c8 | 503 | } |
504 | ||
5260325f | 505 | /* |
506 | * Performs the interactive session. This handles data transmission between | |
507 | * the client and the program. Note that the notion of stdin, stdout, and | |
508 | * stderr in this function is sort of reversed: this function writes to | |
509 | * stdin (of the child program), and reads from stdout and stderr (of the | |
510 | * child program). | |
511 | */ | |
6ae2364d | 512 | void |
9da5c3c9 | 513 | server_loop(pid_t pid, int fdin_arg, int fdout_arg, int fderr_arg) |
8efc0c15 | 514 | { |
39929cdb | 515 | fd_set *readset = NULL, *writeset = NULL; |
9a995072 | 516 | int max_fd = 0; |
517 | u_int nalloc = 0; | |
9da5c3c9 | 518 | int wait_status; /* Status returned by wait(). */ |
519 | pid_t wait_pid; /* pid returned by wait(). */ | |
5260325f | 520 | int waiting_termination = 0; /* Have displayed waiting close message. */ |
1e3b8b07 | 521 | u_int max_time_milliseconds; |
522 | u_int previous_stdout_buffer_bytes; | |
523 | u_int stdout_buffer_bytes; | |
5260325f | 524 | int type; |
525 | ||
526 | debug("Entering interactive session."); | |
527 | ||
528 | /* Initialize the SIGCHLD kludge. */ | |
5260325f | 529 | child_terminated = 0; |
42ad0eec | 530 | mysignal(SIGCHLD, sigchld_handler); |
5260325f | 531 | |
0bbbf2a4 | 532 | if (!use_privsep) { |
533 | signal(SIGTERM, sigterm_handler); | |
534 | signal(SIGINT, sigterm_handler); | |
535 | signal(SIGQUIT, sigterm_handler); | |
536 | } | |
537 | ||
5260325f | 538 | /* Initialize our global variables. */ |
539 | fdin = fdin_arg; | |
540 | fdout = fdout_arg; | |
541 | fderr = fderr_arg; | |
0e73cc53 | 542 | |
543 | /* nonblocking IO */ | |
544 | set_nonblock(fdin); | |
545 | set_nonblock(fdout); | |
ff873e98 | 546 | /* we don't have stderr for interactive terminal sessions, see below */ |
547 | if (fderr != -1) | |
548 | set_nonblock(fderr); | |
0e73cc53 | 549 | |
e68225b2 | 550 | if (!(datafellows & SSH_BUG_IGNOREMSG) && isatty(fdin)) |
551 | fdin_is_tty = 1; | |
552 | ||
5260325f | 553 | connection_in = packet_get_connection_in(); |
554 | connection_out = packet_get_connection_out(); | |
555 | ||
a10be357 | 556 | notify_setup(); |
557 | ||
5260325f | 558 | previous_stdout_buffer_bytes = 0; |
559 | ||
560 | /* Set approximate I/O buffer size. */ | |
561 | if (packet_is_interactive()) | |
562 | buffer_high = 4096; | |
563 | else | |
564 | buffer_high = 64 * 1024; | |
565 | ||
489aa2e9 | 566 | #if 0 |
5260325f | 567 | /* Initialize max_fd to the maximum of the known file descriptors. */ |
489aa2e9 | 568 | max_fd = MAX(connection_in, connection_out); |
569 | max_fd = MAX(max_fd, fdin); | |
570 | max_fd = MAX(max_fd, fdout); | |
39929cdb | 571 | if (fderr != -1) |
572 | max_fd = MAX(max_fd, fderr); | |
489aa2e9 | 573 | #endif |
5260325f | 574 | |
575 | /* Initialize Initialize buffers. */ | |
576 | buffer_init(&stdin_buffer); | |
577 | buffer_init(&stdout_buffer); | |
578 | buffer_init(&stderr_buffer); | |
579 | ||
aa3378df | 580 | /* |
581 | * If we have no separate fderr (which is the case when we have a pty | |
582 | * - there we cannot make difference between data sent to stdout and | |
583 | * stderr), indicate that we have seen an EOF from stderr. This way | |
7b9b0103 | 584 | * we don't need to check the descriptor everywhere. |
aa3378df | 585 | */ |
5260325f | 586 | if (fderr == -1) |
587 | fderr_eof = 1; | |
588 | ||
7368a6c8 | 589 | server_init_dispatch(); |
590 | ||
5260325f | 591 | /* Main loop of the server for the interactive session mode. */ |
592 | for (;;) { | |
5260325f | 593 | |
594 | /* Process buffered packets from the client. */ | |
595 | process_buffered_input_packets(); | |
596 | ||
aa3378df | 597 | /* |
598 | * If we have received eof, and there is no more pending | |
599 | * input data, cause a real eof by closing fdin. | |
600 | */ | |
5260325f | 601 | if (stdin_eof && fdin != -1 && buffer_len(&stdin_buffer) == 0) { |
7368a6c8 | 602 | if (fdin != fdout) |
5260325f | 603 | close(fdin); |
604 | else | |
605 | shutdown(fdin, SHUT_WR); /* We will no longer send. */ | |
5260325f | 606 | fdin = -1; |
607 | } | |
aa3378df | 608 | /* Make packets from buffered stderr data to send to the client. */ |
5260325f | 609 | make_packets_from_stderr_data(); |
610 | ||
aa3378df | 611 | /* |
612 | * Make packets from buffered stdout data to send to the | |
613 | * client. If there is very little to send, this arranges to | |
614 | * not send them now, but to wait a short while to see if we | |
615 | * are getting more data. This is necessary, as some systems | |
616 | * wake up readers from a pty after each separate character. | |
617 | */ | |
5260325f | 618 | max_time_milliseconds = 0; |
619 | stdout_buffer_bytes = buffer_len(&stdout_buffer); | |
620 | if (stdout_buffer_bytes != 0 && stdout_buffer_bytes < 256 && | |
621 | stdout_buffer_bytes != previous_stdout_buffer_bytes) { | |
622 | /* try again after a while */ | |
623 | max_time_milliseconds = 10; | |
624 | } else { | |
625 | /* Send it now. */ | |
626 | make_packets_from_stdout_data(); | |
627 | } | |
628 | previous_stdout_buffer_bytes = buffer_len(&stdout_buffer); | |
629 | ||
630 | /* Send channel data to the client. */ | |
631 | if (packet_not_very_much_data_to_write()) | |
632 | channel_output_poll(); | |
633 | ||
aa3378df | 634 | /* |
635 | * Bail out of the loop if the program has closed its output | |
636 | * descriptors, and we have no more data to send to the | |
637 | * client, and there is no pending buffered data. | |
638 | */ | |
7062c40f | 639 | if (fdout_eof && fderr_eof && !packet_have_data_to_write() && |
640 | buffer_len(&stdout_buffer) == 0 && buffer_len(&stderr_buffer) == 0) { | |
5260325f | 641 | if (!channel_still_open()) |
7368a6c8 | 642 | break; |
5260325f | 643 | if (!waiting_termination) { |
644 | const char *s = "Waiting for forwarded connections to terminate...\r\n"; | |
645 | char *cp; | |
646 | waiting_termination = 1; | |
647 | buffer_append(&stderr_buffer, s, strlen(s)); | |
648 | ||
649 | /* Display list of open channels. */ | |
650 | cp = channel_open_message(); | |
651 | buffer_append(&stderr_buffer, cp, strlen(cp)); | |
652 | xfree(cp); | |
653 | } | |
654 | } | |
489aa2e9 | 655 | max_fd = MAX(connection_in, connection_out); |
656 | max_fd = MAX(max_fd, fdin); | |
657 | max_fd = MAX(max_fd, fdout); | |
658 | max_fd = MAX(max_fd, fderr); | |
a10be357 | 659 | max_fd = MAX(max_fd, notify_pipe[0]); |
489aa2e9 | 660 | |
5260325f | 661 | /* Sleep in select() until we can do something. */ |
39929cdb | 662 | wait_until_can_do_something(&readset, &writeset, &max_fd, |
489aa2e9 | 663 | &nalloc, max_time_milliseconds); |
5260325f | 664 | |
0bbbf2a4 | 665 | if (received_sigterm) { |
666 | logit("Exiting on signal %d", received_sigterm); | |
667 | /* Clean up sessions, utmp, etc. */ | |
668 | cleanup_exit(255); | |
669 | } | |
670 | ||
5260325f | 671 | /* Process any channel events. */ |
39929cdb | 672 | channel_after_select(readset, writeset); |
5260325f | 673 | |
674 | /* Process input from the client and from program stdout/stderr. */ | |
39929cdb | 675 | process_input(readset); |
5260325f | 676 | |
677 | /* Process output to the client and to program stdin. */ | |
39929cdb | 678 | process_output(writeset); |
8efc0c15 | 679 | } |
39929cdb | 680 | if (readset) |
681 | xfree(readset); | |
682 | if (writeset) | |
683 | xfree(writeset); | |
8efc0c15 | 684 | |
5260325f | 685 | /* Cleanup and termination code. */ |
8efc0c15 | 686 | |
5260325f | 687 | /* Wait until all output has been sent to the client. */ |
688 | drain_output(); | |
8efc0c15 | 689 | |
5260325f | 690 | debug("End of interactive session; stdin %ld, stdout (read %ld, sent %ld), stderr %ld bytes.", |
184eed6a | 691 | stdin_bytes, fdout_bytes, stdout_bytes, stderr_bytes); |
8efc0c15 | 692 | |
5260325f | 693 | /* Free and clear the buffers. */ |
694 | buffer_free(&stdin_buffer); | |
695 | buffer_free(&stdout_buffer); | |
696 | buffer_free(&stderr_buffer); | |
8efc0c15 | 697 | |
5260325f | 698 | /* Close the file descriptors. */ |
699 | if (fdout != -1) | |
700 | close(fdout); | |
701 | fdout = -1; | |
702 | fdout_eof = 1; | |
703 | if (fderr != -1) | |
704 | close(fderr); | |
705 | fderr = -1; | |
706 | fderr_eof = 1; | |
707 | if (fdin != -1) | |
708 | close(fdin); | |
709 | fdin = -1; | |
710 | ||
d6746a0b | 711 | channel_free_all(); |
5260325f | 712 | |
5260325f | 713 | /* We no longer want our SIGCHLD handler to be called. */ |
42ad0eec | 714 | mysignal(SIGCHLD, SIG_DFL); |
5260325f | 715 | |
8c38e88b | 716 | while ((wait_pid = waitpid(-1, &wait_status, 0)) < 0) |
717 | if (errno != EINTR) | |
718 | packet_disconnect("wait: %.100s", strerror(errno)); | |
719 | if (wait_pid != pid) | |
c457707e | 720 | error("Strange, wait returned pid %ld, expected %ld", |
721 | (long)wait_pid, (long)pid); | |
c9130033 | 722 | |
5260325f | 723 | /* Check if it exited normally. */ |
724 | if (WIFEXITED(wait_status)) { | |
725 | /* Yes, normal exit. Get exit status and send it to the client. */ | |
726 | debug("Command exited with status %d.", WEXITSTATUS(wait_status)); | |
727 | packet_start(SSH_SMSG_EXITSTATUS); | |
728 | packet_put_int(WEXITSTATUS(wait_status)); | |
729 | packet_send(); | |
730 | packet_write_wait(); | |
731 | ||
aa3378df | 732 | /* |
733 | * Wait for exit confirmation. Note that there might be | |
734 | * other packets coming before it; however, the program has | |
735 | * already died so we just ignore them. The client is | |
736 | * supposed to respond with the confirmation when it receives | |
737 | * the exit status. | |
738 | */ | |
5260325f | 739 | do { |
54a5250f | 740 | type = packet_read(); |
5260325f | 741 | } |
742 | while (type != SSH_CMSG_EXIT_CONFIRMATION); | |
743 | ||
744 | debug("Received exit confirmation."); | |
745 | return; | |
746 | } | |
747 | /* Check if the program terminated due to a signal. */ | |
748 | if (WIFSIGNALED(wait_status)) | |
749 | packet_disconnect("Command terminated on signal %d.", | |
750 | WTERMSIG(wait_status)); | |
751 | ||
752 | /* Some weird exit cause. Just exit. */ | |
753 | packet_disconnect("wait returned status %04x.", wait_status); | |
754 | /* NOTREACHED */ | |
755 | } | |
7368a6c8 | 756 | |
418e724c | 757 | static void |
758 | collect_children(void) | |
759 | { | |
760 | pid_t pid; | |
761 | sigset_t oset, nset; | |
762 | int status; | |
763 | ||
764 | /* block SIGCHLD while we check for dead children */ | |
765 | sigemptyset(&nset); | |
766 | sigaddset(&nset, SIGCHLD); | |
767 | sigprocmask(SIG_BLOCK, &nset, &oset); | |
768 | if (child_terminated) { | |
140000b4 | 769 | debug("Received SIGCHLD."); |
8c38e88b | 770 | while ((pid = waitpid(-1, &status, WNOHANG)) > 0 || |
771 | (pid < 0 && errno == EINTR)) | |
772 | if (pid > 0) | |
773 | session_close_by_pid(pid, status); | |
418e724c | 774 | child_terminated = 0; |
775 | } | |
776 | sigprocmask(SIG_SETMASK, &oset, NULL); | |
777 | } | |
778 | ||
6ae2364d | 779 | void |
57156994 | 780 | server_loop2(Authctxt *authctxt) |
e78a59f5 | 781 | { |
39929cdb | 782 | fd_set *readset = NULL, *writeset = NULL; |
418e724c | 783 | int rekeying = 0, max_fd, nalloc = 0; |
e78a59f5 | 784 | |
785 | debug("Entering interactive session for SSH2."); | |
786 | ||
c9130033 | 787 | mysignal(SIGCHLD, sigchld_handler); |
e78a59f5 | 788 | child_terminated = 0; |
789 | connection_in = packet_get_connection_in(); | |
790 | connection_out = packet_get_connection_out(); | |
39929cdb | 791 | |
0bbbf2a4 | 792 | if (!use_privsep) { |
793 | signal(SIGTERM, sigterm_handler); | |
794 | signal(SIGINT, sigterm_handler); | |
795 | signal(SIGQUIT, sigterm_handler); | |
796 | } | |
797 | ||
a10be357 | 798 | notify_setup(); |
799 | ||
39929cdb | 800 | max_fd = MAX(connection_in, connection_out); |
a10be357 | 801 | max_fd = MAX(max_fd, notify_pipe[0]); |
802 | ||
e78a59f5 | 803 | server_init_dispatch(); |
804 | ||
805 | for (;;) { | |
806 | process_buffered_input_packets(); | |
bbb4cc1b | 807 | |
cd332296 | 808 | rekeying = (xxx_kex != NULL && !xxx_kex->done); |
bbb4cc1b | 809 | |
bbb4cc1b | 810 | if (!rekeying && packet_not_very_much_data_to_write()) |
e78a59f5 | 811 | channel_output_poll(); |
bbb4cc1b | 812 | wait_until_can_do_something(&readset, &writeset, &max_fd, |
489aa2e9 | 813 | &nalloc, 0); |
d5f24f94 | 814 | |
0bbbf2a4 | 815 | if (received_sigterm) { |
816 | logit("Exiting on signal %d", received_sigterm); | |
817 | /* Clean up sessions, utmp, etc. */ | |
818 | cleanup_exit(255); | |
819 | } | |
820 | ||
418e724c | 821 | collect_children(); |
ffd7b36b | 822 | if (!rekeying) { |
bbb4cc1b | 823 | channel_after_select(readset, writeset); |
ffd7b36b | 824 | if (packet_need_rekeying()) { |
825 | debug("need rekeying"); | |
826 | xxx_kex->done = 0; | |
827 | kex_send_kexinit(xxx_kex); | |
828 | } | |
829 | } | |
39929cdb | 830 | process_input(readset); |
cc94bd38 | 831 | if (connection_closed) |
832 | break; | |
39929cdb | 833 | process_output(writeset); |
e78a59f5 | 834 | } |
418e724c | 835 | collect_children(); |
836 | ||
39929cdb | 837 | if (readset) |
838 | xfree(readset); | |
839 | if (writeset) | |
840 | xfree(writeset); | |
841 | ||
d5f24f94 | 842 | /* free all channels, no more reads and writes */ |
843 | channel_free_all(); | |
5b5d170c | 844 | |
418e724c | 845 | /* free remaining sessions, e.g. remove wtmp entries */ |
1853d1ef | 846 | session_destroy_all(NULL); |
e78a59f5 | 847 | } |
848 | ||
396c147e | 849 | static void |
95ae2076 | 850 | server_input_keep_alive(int type, u_int32_t seq, void *ctxt) |
3ffc6336 | 851 | { |
95ae2076 | 852 | debug("Got %d/%u for keepalive", type, seq); |
184eed6a | 853 | /* |
39aefe7b | 854 | * reset timeout, since we got a sane answer from the client. |
3ffc6336 | 855 | * even if this was generated by something other than |
856 | * the bogus CHANNEL_REQUEST we send for keepalives. | |
857 | */ | |
184eed6a | 858 | client_alive_timeouts = 0; |
3ffc6336 | 859 | } |
860 | ||
396c147e | 861 | static void |
7819b5c3 | 862 | server_input_stdin_data(int type, u_int32_t seq, void *ctxt) |
7368a6c8 | 863 | { |
864 | char *data; | |
1e3b8b07 | 865 | u_int data_len; |
7368a6c8 | 866 | |
867 | /* Stdin data from the client. Append it to the buffer. */ | |
868 | /* Ignore any data if the client has closed stdin. */ | |
869 | if (fdin == -1) | |
870 | return; | |
871 | data = packet_get_string(&data_len); | |
95500969 | 872 | packet_check_eom(); |
7368a6c8 | 873 | buffer_append(&stdin_buffer, data, data_len); |
874 | memset(data, 0, data_len); | |
875 | xfree(data); | |
876 | } | |
877 | ||
396c147e | 878 | static void |
7819b5c3 | 879 | server_input_eof(int type, u_int32_t seq, void *ctxt) |
7368a6c8 | 880 | { |
881 | /* | |
882 | * Eof from the client. The stdin descriptor to the | |
883 | * program will be closed when all buffered data has | |
884 | * drained. | |
885 | */ | |
886 | debug("EOF received for stdin."); | |
95500969 | 887 | packet_check_eom(); |
7368a6c8 | 888 | stdin_eof = 1; |
889 | } | |
890 | ||
396c147e | 891 | static void |
7819b5c3 | 892 | server_input_window_size(int type, u_int32_t seq, void *ctxt) |
7368a6c8 | 893 | { |
148de80c | 894 | u_int row = packet_get_int(); |
895 | u_int col = packet_get_int(); | |
896 | u_int xpixel = packet_get_int(); | |
897 | u_int ypixel = packet_get_int(); | |
7368a6c8 | 898 | |
899 | debug("Window change received."); | |
95500969 | 900 | packet_check_eom(); |
7368a6c8 | 901 | if (fdin != -1) |
902 | pty_change_window_size(fdin, row, col, xpixel, ypixel); | |
903 | } | |
904 | ||
396c147e | 905 | static Channel * |
43f7a4b8 | 906 | server_request_direct_tcpip(void) |
e78a59f5 | 907 | { |
719fc62f | 908 | Channel *c; |
909 | int sock; | |
6ae2364d | 910 | char *target, *originator; |
911 | int target_port, originator_port; | |
e78a59f5 | 912 | |
6ae2364d | 913 | target = packet_get_string(NULL); |
914 | target_port = packet_get_int(); | |
e78a59f5 | 915 | originator = packet_get_string(NULL); |
916 | originator_port = packet_get_int(); | |
95500969 | 917 | packet_check_eom(); |
71276795 | 918 | |
fa08c86b | 919 | debug("server_request_direct_tcpip: originator %s port %d, target %s port %d", |
4e2e5cfd | 920 | originator, originator_port, target, target_port); |
38c295d6 | 921 | |
e78a59f5 | 922 | /* XXX check permission */ |
6ae2364d | 923 | sock = channel_connect_to(target, target_port); |
924 | xfree(target); | |
e78a59f5 | 925 | xfree(originator); |
926 | if (sock < 0) | |
fa08c86b | 927 | return NULL; |
43f7a4b8 | 928 | c = channel_new("direct-tcpip", SSH_CHANNEL_CONNECTING, |
bcbf86ec | 929 | sock, sock, -1, CHAN_TCP_WINDOW_DEFAULT, |
0d942eff | 930 | CHAN_TCP_PACKET_DEFAULT, 0, "direct-tcpip", 1); |
719fc62f | 931 | return c; |
fa08c86b | 932 | } |
933 | ||
d20f3c9e | 934 | static Channel * |
935 | server_request_tun(void) | |
936 | { | |
937 | Channel *c = NULL; | |
a4f24bf8 | 938 | int mode, tun; |
939 | int sock; | |
d20f3c9e | 940 | |
a4f24bf8 | 941 | mode = packet_get_int(); |
942 | switch (mode) { | |
943 | case SSH_TUNMODE_POINTOPOINT: | |
944 | case SSH_TUNMODE_ETHERNET: | |
945 | break; | |
946 | default: | |
947 | packet_send_debug("Unsupported tunnel device mode."); | |
948 | return NULL; | |
949 | } | |
950 | if ((options.permit_tun & mode) == 0) { | |
951 | packet_send_debug("Server has rejected tunnel device " | |
952 | "forwarding"); | |
d20f3c9e | 953 | return NULL; |
954 | } | |
955 | ||
956 | tun = packet_get_int(); | |
a2b1748a | 957 | if (forced_tun_device != -1) { |
3efa8ea9 | 958 | if (tun != SSH_TUNID_ANY && forced_tun_device != tun) |
d20f3c9e | 959 | goto done; |
960 | tun = forced_tun_device; | |
961 | } | |
a4f24bf8 | 962 | sock = tun_open(tun, mode); |
d20f3c9e | 963 | if (sock < 0) |
964 | goto done; | |
965 | c = channel_new("tun", SSH_CHANNEL_OPEN, sock, sock, -1, | |
966 | CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, "tun", 1); | |
967 | c->datagram = 1; | |
e914f53a | 968 | #if defined(SSH_TUN_FILTER) |
969 | if (mode == SSH_TUNMODE_POINTOPOINT) | |
970 | channel_register_filter(c->self, sys_tun_infilter, | |
971 | sys_tun_outfilter); | |
972 | #endif | |
d20f3c9e | 973 | |
974 | done: | |
975 | if (c == NULL) | |
976 | packet_send_debug("Failed to open the tunnel device."); | |
977 | return c; | |
978 | } | |
979 | ||
396c147e | 980 | static Channel * |
43f7a4b8 | 981 | server_request_session(void) |
fa08c86b | 982 | { |
719fc62f | 983 | Channel *c; |
fa08c86b | 984 | |
985 | debug("input_session_request"); | |
95500969 | 986 | packet_check_eom(); |
fa08c86b | 987 | /* |
988 | * A server session has no fd to read or write until a | |
989 | * CHANNEL_REQUEST for a shell is made, so we set the type to | |
990 | * SSH_CHANNEL_LARVAL. Additionally, a callback for handling all | |
991 | * CHANNEL_REQUEST messages is registered. | |
992 | */ | |
43f7a4b8 | 993 | c = channel_new("session", SSH_CHANNEL_LARVAL, |
719fc62f | 994 | -1, -1, -1, /*window size*/0, CHAN_SES_PACKET_DEFAULT, |
0d942eff | 995 | 0, "server-session", 1); |
2362db19 | 996 | if (session_open(the_authctxt, c->self) != 1) { |
719fc62f | 997 | debug("session open failed, free channel %d", c->self); |
998 | channel_free(c); | |
999 | return NULL; | |
fa08c86b | 1000 | } |
8cd0437d | 1001 | channel_register_cleanup(c->self, session_close_by_channel, 0); |
719fc62f | 1002 | return c; |
e78a59f5 | 1003 | } |
1004 | ||
396c147e | 1005 | static void |
7819b5c3 | 1006 | server_input_channel_open(int type, u_int32_t seq, void *ctxt) |
e78a59f5 | 1007 | { |
1008 | Channel *c = NULL; | |
1009 | char *ctype; | |
e78a59f5 | 1010 | int rchan; |
f91d9a89 | 1011 | u_int rmaxpack, rwindow, len; |
e78a59f5 | 1012 | |
1013 | ctype = packet_get_string(&len); | |
1014 | rchan = packet_get_int(); | |
1015 | rwindow = packet_get_int(); | |
1016 | rmaxpack = packet_get_int(); | |
1017 | ||
188adeb2 | 1018 | debug("server_input_channel_open: ctype %s rchan %d win %d max %d", |
e78a59f5 | 1019 | ctype, rchan, rwindow, rmaxpack); |
1020 | ||
1021 | if (strcmp(ctype, "session") == 0) { | |
43f7a4b8 | 1022 | c = server_request_session(); |
e78a59f5 | 1023 | } else if (strcmp(ctype, "direct-tcpip") == 0) { |
43f7a4b8 | 1024 | c = server_request_direct_tcpip(); |
d20f3c9e | 1025 | } else if (strcmp(ctype, "tun@openssh.com") == 0) { |
1026 | c = server_request_tun(); | |
e78a59f5 | 1027 | } |
1028 | if (c != NULL) { | |
fa08c86b | 1029 | debug("server_input_channel_open: confirm %s", ctype); |
e78a59f5 | 1030 | c->remote_id = rchan; |
1031 | c->remote_window = rwindow; | |
1032 | c->remote_maxpacket = rmaxpack; | |
d18e0850 | 1033 | if (c->type != SSH_CHANNEL_CONNECTING) { |
1034 | packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1035 | packet_put_int(c->remote_id); | |
1036 | packet_put_int(c->self); | |
1037 | packet_put_int(c->local_window); | |
1038 | packet_put_int(c->local_maxpacket); | |
1039 | packet_send(); | |
1040 | } | |
e78a59f5 | 1041 | } else { |
fa08c86b | 1042 | debug("server_input_channel_open: failure %s", ctype); |
e78a59f5 | 1043 | packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE); |
1044 | packet_put_int(rchan); | |
1045 | packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED); | |
fbe90f7b | 1046 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { |
d18e0850 | 1047 | packet_put_cstring("open failed"); |
fbe90f7b | 1048 | packet_put_cstring(""); |
1049 | } | |
e78a59f5 | 1050 | packet_send(); |
1051 | } | |
1052 | xfree(ctype); | |
1053 | } | |
1054 | ||
396c147e | 1055 | static void |
7819b5c3 | 1056 | server_input_global_request(int type, u_int32_t seq, void *ctxt) |
fa08c86b | 1057 | { |
1058 | char *rtype; | |
1059 | int want_reply; | |
1060 | int success = 0; | |
1061 | ||
1062 | rtype = packet_get_string(NULL); | |
1063 | want_reply = packet_get_char(); | |
1064 | debug("server_input_global_request: rtype %s want_reply %d", rtype, want_reply); | |
2b87da3b | 1065 | |
01794848 | 1066 | /* -R style forwarding */ |
fa08c86b | 1067 | if (strcmp(rtype, "tcpip-forward") == 0) { |
1068 | struct passwd *pw; | |
1069 | char *listen_address; | |
1070 | u_short listen_port; | |
1071 | ||
2362db19 | 1072 | pw = the_authctxt->pw; |
95077f48 | 1073 | if (pw == NULL || !the_authctxt->valid) |
fdaef11e | 1074 | fatal("server_input_global_request: no/invalid user"); |
b08a39ff | 1075 | listen_address = packet_get_string(NULL); |
fa08c86b | 1076 | listen_port = (u_short)packet_get_int(); |
1077 | debug("server_input_global_request: tcpip-forward listen %s port %d", | |
1078 | listen_address, listen_port); | |
1079 | ||
1080 | /* check permissions */ | |
1081 | if (!options.allow_tcp_forwarding || | |
e6f15ed1 | 1082 | no_port_forwarding_flag |
1083 | #ifndef NO_IPPORT_RESERVED_CONCEPT | |
1084 | || (listen_port < IPPORT_RESERVED && pw->pw_uid != 0) | |
1085 | #endif | |
98c044d0 | 1086 | ) { |
fa08c86b | 1087 | success = 0; |
1088 | packet_send_debug("Server has disabled port forwarding."); | |
1089 | } else { | |
1090 | /* Start listening on the port */ | |
5641aefa | 1091 | success = channel_setup_remote_fwd_listener( |
1092 | listen_address, listen_port, options.gateway_ports); | |
fa08c86b | 1093 | } |
1094 | xfree(listen_address); | |
d740ec16 | 1095 | } else if (strcmp(rtype, "cancel-tcpip-forward") == 0) { |
1096 | char *cancel_address; | |
1097 | u_short cancel_port; | |
1098 | ||
1099 | cancel_address = packet_get_string(NULL); | |
1100 | cancel_port = (u_short)packet_get_int(); | |
1101 | debug("%s: cancel-tcpip-forward addr %s port %d", __func__, | |
1102 | cancel_address, cancel_port); | |
1103 | ||
1104 | success = channel_cancel_rport_listener(cancel_address, | |
1105 | cancel_port); | |
4113a1d7 | 1106 | xfree(cancel_address); |
fa08c86b | 1107 | } |
1108 | if (want_reply) { | |
1109 | packet_start(success ? | |
1110 | SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE); | |
1111 | packet_send(); | |
1112 | packet_write_wait(); | |
1113 | } | |
1114 | xfree(rtype); | |
1115 | } | |
a7137f6b | 1116 | |
7899c98f | 1117 | static void |
1118 | server_input_channel_req(int type, u_int32_t seq, void *ctxt) | |
1119 | { | |
1120 | Channel *c; | |
1121 | int id, reply, success = 0; | |
1122 | char *rtype; | |
1123 | ||
1124 | id = packet_get_int(); | |
1125 | rtype = packet_get_string(NULL); | |
1126 | reply = packet_get_char(); | |
1127 | ||
1128 | debug("server_input_channel_req: channel %d request %s reply %d", | |
1129 | id, rtype, reply); | |
1130 | ||
1131 | if ((c = channel_lookup(id)) == NULL) | |
1132 | packet_disconnect("server_input_channel_req: " | |
1133 | "unknown channel %d", id); | |
1134 | if (c->type == SSH_CHANNEL_LARVAL || c->type == SSH_CHANNEL_OPEN) | |
1135 | success = session_input_channel_req(c, rtype); | |
1136 | if (reply) { | |
1137 | packet_start(success ? | |
1138 | SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE); | |
1139 | packet_put_int(c->remote_id); | |
1140 | packet_send(); | |
1141 | } | |
1142 | xfree(rtype); | |
1143 | } | |
fa08c86b | 1144 | |
396c147e | 1145 | static void |
5ca51e19 | 1146 | server_init_dispatch_20(void) |
e78a59f5 | 1147 | { |
1148 | debug("server_init_dispatch_20"); | |
1149 | dispatch_init(&dispatch_protocol_error); | |
1150 | dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose); | |
1151 | dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data); | |
1152 | dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof); | |
1153 | dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data); | |
1154 | dispatch_set(SSH2_MSG_CHANNEL_OPEN, &server_input_channel_open); | |
1155 | dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation); | |
1156 | dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure); | |
7899c98f | 1157 | dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &server_input_channel_req); |
e78a59f5 | 1158 | dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust); |
fa08c86b | 1159 | dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &server_input_global_request); |
3ffc6336 | 1160 | /* client_alive */ |
95ae2076 | 1161 | dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &server_input_keep_alive); |
1162 | dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &server_input_keep_alive); | |
1163 | dispatch_set(SSH2_MSG_REQUEST_FAILURE, &server_input_keep_alive); | |
7a37c112 | 1164 | /* rekeying */ |
1165 | dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit); | |
e78a59f5 | 1166 | } |
396c147e | 1167 | static void |
5ca51e19 | 1168 | server_init_dispatch_13(void) |
7368a6c8 | 1169 | { |
1170 | debug("server_init_dispatch_13"); | |
1171 | dispatch_init(NULL); | |
1172 | dispatch_set(SSH_CMSG_EOF, &server_input_eof); | |
1173 | dispatch_set(SSH_CMSG_STDIN_DATA, &server_input_stdin_data); | |
1174 | dispatch_set(SSH_CMSG_WINDOW_SIZE, &server_input_window_size); | |
1175 | dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close); | |
1176 | dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation); | |
1177 | dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data); | |
1178 | dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation); | |
1179 | dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure); | |
1180 | dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open); | |
1181 | } | |
396c147e | 1182 | static void |
5ca51e19 | 1183 | server_init_dispatch_15(void) |
7368a6c8 | 1184 | { |
1185 | server_init_dispatch_13(); | |
1186 | debug("server_init_dispatch_15"); | |
1187 | dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof); | |
1188 | dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_oclose); | |
1189 | } | |
396c147e | 1190 | static void |
5ca51e19 | 1191 | server_init_dispatch(void) |
7368a6c8 | 1192 | { |
e78a59f5 | 1193 | if (compat20) |
1194 | server_init_dispatch_20(); | |
1195 | else if (compat13) | |
7368a6c8 | 1196 | server_init_dispatch_13(); |
1197 | else | |
1198 | server_init_dispatch_15(); | |
1199 | } |