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9794d008 | 1 | /* $OpenBSD: serverloop.c,v 1.136 2006/07/05 02:42:09 stevesk 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> | |
9794d008 | 42 | #include <sys/socket.h> |
43 | ||
44 | #include <netinet/in.h> | |
1d3e026f | 45 | |
ada68823 | 46 | #include <signal.h> |
1d3e026f | 47 | #include <termios.h> |
a22aff1f | 48 | |
8efc0c15 | 49 | #include "xmalloc.h" |
8efc0c15 | 50 | #include "packet.h" |
51 | #include "buffer.h" | |
42f11eb2 | 52 | #include "log.h" |
8efc0c15 | 53 | #include "servconf.h" |
00e842d8 | 54 | #include "canohost.h" |
1729c161 | 55 | #include "sshpty.h" |
a5efa1bb | 56 | #include "channels.h" |
7368a6c8 | 57 | #include "compat.h" |
42f11eb2 | 58 | #include "ssh1.h" |
e78a59f5 | 59 | #include "ssh2.h" |
59c97189 | 60 | #include "auth.h" |
e78a59f5 | 61 | #include "session.h" |
7368a6c8 | 62 | #include "dispatch.h" |
38c295d6 | 63 | #include "auth-options.h" |
42f11eb2 | 64 | #include "serverloop.h" |
65 | #include "misc.h" | |
7a37c112 | 66 | #include "kex.h" |
8efc0c15 | 67 | |
33de75a3 | 68 | extern ServerOptions options; |
69 | ||
7a37c112 | 70 | /* XXX */ |
71 | extern Kex *xxx_kex; | |
2362db19 | 72 | extern Authctxt *the_authctxt; |
0bbbf2a4 | 73 | extern int use_privsep; |
7a37c112 | 74 | |
8efc0c15 | 75 | static Buffer stdin_buffer; /* Buffer for stdin data. */ |
76 | static Buffer stdout_buffer; /* Buffer for stdout data. */ | |
77 | static Buffer stderr_buffer; /* Buffer for stderr data. */ | |
78 | static int fdin; /* Descriptor for stdin (for writing) */ | |
79 | static int fdout; /* Descriptor for stdout (for reading); | |
80 | May be same number as fdin. */ | |
81 | static int fderr; /* Descriptor for stderr. May be -1. */ | |
82 | static long stdin_bytes = 0; /* Number of bytes written to stdin. */ | |
83 | static long stdout_bytes = 0; /* Number of stdout bytes sent to client. */ | |
84 | static long stderr_bytes = 0; /* Number of stderr bytes sent to client. */ | |
85 | static long fdout_bytes = 0; /* Number of stdout bytes read from program. */ | |
86 | static int stdin_eof = 0; /* EOF message received from client. */ | |
87 | static int fdout_eof = 0; /* EOF encountered reading from fdout. */ | |
88 | static int fderr_eof = 0; /* EOF encountered readung from fderr. */ | |
e68225b2 | 89 | static int fdin_is_tty = 0; /* fdin points to a tty. */ |
8efc0c15 | 90 | static int connection_in; /* Connection to client (input). */ |
91 | static int connection_out; /* Connection to client (output). */ | |
cc94bd38 | 92 | static int connection_closed = 0; /* Connection to client closed. */ |
93 | static u_int buffer_high; /* "Soft" max buffer size. */ | |
72176c0e | 94 | static int client_alive_timeouts = 0; |
8efc0c15 | 95 | |
aa3378df | 96 | /* |
97 | * This SIGCHLD kludge is used to detect when the child exits. The server | |
98 | * will exit after that, as soon as forwarded connections have terminated. | |
99 | */ | |
396c147e | 100 | |
7a934d1b | 101 | static volatile sig_atomic_t child_terminated = 0; /* The child has terminated. */ |
8efc0c15 | 102 | |
0bbbf2a4 | 103 | /* Cleanup on signals (!use_privsep case only) */ |
104 | static volatile sig_atomic_t received_sigterm = 0; | |
105 | ||
396c147e | 106 | /* prototypes */ |
107 | static void server_init_dispatch(void); | |
7368a6c8 | 108 | |
a10be357 | 109 | /* |
110 | * we write to this pipe if a SIGCHLD is caught in order to avoid | |
111 | * the race between select() and child_terminated | |
112 | */ | |
113 | static int notify_pipe[2]; | |
114 | static void | |
115 | notify_setup(void) | |
116 | { | |
117 | if (pipe(notify_pipe) < 0) { | |
118 | error("pipe(notify_pipe) failed %s", strerror(errno)); | |
119 | } else if ((fcntl(notify_pipe[0], F_SETFD, 1) == -1) || | |
120 | (fcntl(notify_pipe[1], F_SETFD, 1) == -1)) { | |
121 | error("fcntl(notify_pipe, F_SETFD) failed %s", strerror(errno)); | |
122 | close(notify_pipe[0]); | |
123 | close(notify_pipe[1]); | |
124 | } else { | |
125 | set_nonblock(notify_pipe[0]); | |
126 | set_nonblock(notify_pipe[1]); | |
127 | return; | |
128 | } | |
129 | notify_pipe[0] = -1; /* read end */ | |
130 | notify_pipe[1] = -1; /* write end */ | |
131 | } | |
132 | static void | |
133 | notify_parent(void) | |
134 | { | |
135 | if (notify_pipe[1] != -1) | |
136 | write(notify_pipe[1], "", 1); | |
137 | } | |
138 | static void | |
139 | notify_prepare(fd_set *readset) | |
140 | { | |
141 | if (notify_pipe[0] != -1) | |
142 | FD_SET(notify_pipe[0], readset); | |
143 | } | |
144 | static void | |
145 | notify_done(fd_set *readset) | |
146 | { | |
147 | char c; | |
148 | ||
149 | if (notify_pipe[0] != -1 && FD_ISSET(notify_pipe[0], readset)) | |
150 | while (read(notify_pipe[0], &c, 1) != -1) | |
151 | debug2("notify_done: reading"); | |
152 | } | |
153 | ||
3efa8ea9 | 154 | /*ARGSUSED*/ |
396c147e | 155 | static void |
5260325f | 156 | sigchld_handler(int sig) |
e78a59f5 | 157 | { |
158 | int save_errno = errno; | |
e78a59f5 | 159 | child_terminated = 1; |
ef51930f | 160 | #ifndef _UNICOS |
c9130033 | 161 | mysignal(SIGCHLD, sigchld_handler); |
ef51930f | 162 | #endif |
a10be357 | 163 | notify_parent(); |
e78a59f5 | 164 | errno = save_errno; |
165 | } | |
8efc0c15 | 166 | |
3efa8ea9 | 167 | /*ARGSUSED*/ |
0bbbf2a4 | 168 | static void |
169 | sigterm_handler(int sig) | |
170 | { | |
171 | received_sigterm = sig; | |
172 | } | |
173 | ||
5260325f | 174 | /* |
175 | * Make packets from buffered stderr data, and buffer it for sending | |
176 | * to the client. | |
177 | */ | |
396c147e | 178 | static void |
5ca51e19 | 179 | make_packets_from_stderr_data(void) |
8efc0c15 | 180 | { |
a27002e5 | 181 | u_int len; |
5260325f | 182 | |
183 | /* Send buffered stderr data to the client. */ | |
184 | while (buffer_len(&stderr_buffer) > 0 && | |
a408af76 | 185 | packet_not_very_much_data_to_write()) { |
5260325f | 186 | len = buffer_len(&stderr_buffer); |
187 | if (packet_is_interactive()) { | |
188 | if (len > 512) | |
189 | len = 512; | |
190 | } else { | |
191 | /* Keep the packets at reasonable size. */ | |
192 | if (len > packet_get_maxsize()) | |
193 | len = packet_get_maxsize(); | |
194 | } | |
195 | packet_start(SSH_SMSG_STDERR_DATA); | |
196 | packet_put_string(buffer_ptr(&stderr_buffer), len); | |
197 | packet_send(); | |
198 | buffer_consume(&stderr_buffer, len); | |
199 | stderr_bytes += len; | |
8efc0c15 | 200 | } |
8efc0c15 | 201 | } |
202 | ||
5260325f | 203 | /* |
204 | * Make packets from buffered stdout data, and buffer it for sending to the | |
205 | * client. | |
206 | */ | |
396c147e | 207 | static void |
5ca51e19 | 208 | make_packets_from_stdout_data(void) |
8efc0c15 | 209 | { |
a27002e5 | 210 | u_int len; |
5260325f | 211 | |
212 | /* Send buffered stdout data to the client. */ | |
213 | while (buffer_len(&stdout_buffer) > 0 && | |
a408af76 | 214 | packet_not_very_much_data_to_write()) { |
5260325f | 215 | len = buffer_len(&stdout_buffer); |
216 | if (packet_is_interactive()) { | |
217 | if (len > 512) | |
218 | len = 512; | |
219 | } else { | |
220 | /* Keep the packets at reasonable size. */ | |
221 | if (len > packet_get_maxsize()) | |
2b87da3b | 222 | len = packet_get_maxsize(); |
5260325f | 223 | } |
224 | packet_start(SSH_SMSG_STDOUT_DATA); | |
225 | packet_put_string(buffer_ptr(&stdout_buffer), len); | |
226 | packet_send(); | |
227 | buffer_consume(&stdout_buffer, len); | |
228 | stdout_bytes += len; | |
8efc0c15 | 229 | } |
8efc0c15 | 230 | } |
231 | ||
72176c0e | 232 | static void |
233 | client_alive_check(void) | |
234 | { | |
95ae2076 | 235 | int channel_id; |
99416ceb | 236 | |
72176c0e | 237 | /* timeout, check to see how many we have had */ |
238 | if (++client_alive_timeouts > options.client_alive_count_max) | |
239 | packet_disconnect("Timeout, your session not responding."); | |
240 | ||
72176c0e | 241 | /* |
95ae2076 | 242 | * send a bogus global/channel request with "wantreply", |
72176c0e | 243 | * we should get back a failure |
244 | */ | |
95ae2076 | 245 | if ((channel_id = channel_find_open()) == -1) { |
246 | packet_start(SSH2_MSG_GLOBAL_REQUEST); | |
247 | packet_put_cstring("keepalive@openssh.com"); | |
248 | packet_put_char(1); /* boolean: want reply */ | |
249 | } else { | |
250 | channel_request_start(channel_id, "keepalive@openssh.com", 1); | |
251 | } | |
72176c0e | 252 | packet_send(); |
253 | } | |
254 | ||
5260325f | 255 | /* |
256 | * Sleep in select() until we can do something. This will initialize the | |
257 | * select masks. Upon return, the masks will indicate which descriptors | |
258 | * have data or can accept data. Optionally, a maximum time can be specified | |
259 | * for the duration of the wait (0 = infinite). | |
260 | */ | |
396c147e | 261 | static void |
39929cdb | 262 | wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp, int *maxfdp, |
9a995072 | 263 | u_int *nallocp, u_int max_time_milliseconds) |
8efc0c15 | 264 | { |
5260325f | 265 | struct timeval tv, *tvp; |
266 | int ret; | |
3ffc6336 | 267 | int client_alive_scheduled = 0; |
268 | ||
269 | /* | |
184eed6a | 270 | * if using client_alive, set the max timeout accordingly, |
3ffc6336 | 271 | * and indicate that this particular timeout was for client |
272 | * alive by setting the client_alive_scheduled flag. | |
273 | * | |
274 | * this could be randomized somewhat to make traffic | |
184eed6a | 275 | * analysis more difficult, but we're not doing it yet. |
3ffc6336 | 276 | */ |
2c5b1791 | 277 | if (compat20 && |
278 | max_time_milliseconds == 0 && options.client_alive_interval) { | |
39aefe7b | 279 | client_alive_scheduled = 1; |
3ffc6336 | 280 | max_time_milliseconds = options.client_alive_interval * 1000; |
2c5b1791 | 281 | } |
8efc0c15 | 282 | |
39929cdb | 283 | /* Allocate and update select() masks for channel descriptors. */ |
489aa2e9 | 284 | channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, 0); |
5260325f | 285 | |
e78a59f5 | 286 | if (compat20) { |
0c139bd1 | 287 | #if 0 |
1d1ffb87 | 288 | /* wrong: bad condition XXX */ |
e78a59f5 | 289 | if (channel_not_very_much_buffered_data()) |
0c139bd1 | 290 | #endif |
291 | FD_SET(connection_in, *readsetp); | |
e78a59f5 | 292 | } else { |
71276795 | 293 | /* |
294 | * Read packets from the client unless we have too much | |
295 | * buffered stdin or channel data. | |
296 | */ | |
297 | if (buffer_len(&stdin_buffer) < buffer_high && | |
e78a59f5 | 298 | channel_not_very_much_buffered_data()) |
39929cdb | 299 | FD_SET(connection_in, *readsetp); |
71276795 | 300 | /* |
301 | * If there is not too much data already buffered going to | |
302 | * the client, try to get some more data from the program. | |
303 | */ | |
304 | if (packet_not_very_much_data_to_write()) { | |
305 | if (!fdout_eof) | |
39929cdb | 306 | FD_SET(fdout, *readsetp); |
71276795 | 307 | if (!fderr_eof) |
39929cdb | 308 | FD_SET(fderr, *readsetp); |
71276795 | 309 | } |
310 | /* | |
311 | * If we have buffered data, try to write some of that data | |
312 | * to the program. | |
313 | */ | |
314 | if (fdin != -1 && buffer_len(&stdin_buffer) > 0) | |
39929cdb | 315 | FD_SET(fdin, *writesetp); |
e78a59f5 | 316 | } |
a10be357 | 317 | notify_prepare(*readsetp); |
5260325f | 318 | |
aa3378df | 319 | /* |
320 | * If we have buffered packet data going to the client, mark that | |
321 | * descriptor. | |
322 | */ | |
5260325f | 323 | if (packet_have_data_to_write()) |
39929cdb | 324 | FD_SET(connection_out, *writesetp); |
5260325f | 325 | |
aa3378df | 326 | /* |
327 | * If child has terminated and there is enough buffer space to read | |
328 | * from it, then read as much as is available and exit. | |
329 | */ | |
5260325f | 330 | if (child_terminated && packet_not_very_much_data_to_write()) |
3ffc6336 | 331 | if (max_time_milliseconds == 0 || client_alive_scheduled) |
5260325f | 332 | max_time_milliseconds = 100; |
333 | ||
334 | if (max_time_milliseconds == 0) | |
335 | tvp = NULL; | |
336 | else { | |
337 | tv.tv_sec = max_time_milliseconds / 1000; | |
338 | tv.tv_usec = 1000 * (max_time_milliseconds % 1000); | |
339 | tvp = &tv; | |
340 | } | |
8efc0c15 | 341 | |
5260325f | 342 | /* Wait for something to happen, or the timeout to expire. */ |
39929cdb | 343 | ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp); |
8efc0c15 | 344 | |
3ffc6336 | 345 | if (ret == -1) { |
b3ad8fe6 | 346 | memset(*readsetp, 0, *nallocp); |
347 | memset(*writesetp, 0, *nallocp); | |
5260325f | 348 | if (errno != EINTR) |
349 | error("select: %.100s", strerror(errno)); | |
418e724c | 350 | } else if (ret == 0 && client_alive_scheduled) |
72176c0e | 351 | client_alive_check(); |
a10be357 | 352 | |
353 | notify_done(*readsetp); | |
8efc0c15 | 354 | } |
355 | ||
5260325f | 356 | /* |
357 | * Processes input from the client and the program. Input data is stored | |
358 | * in buffers and processed later. | |
359 | */ | |
396c147e | 360 | static void |
b476adfa | 361 | process_input(fd_set *readset) |
5260325f | 362 | { |
363 | int len; | |
364 | char buf[16384]; | |
365 | ||
366 | /* Read and buffer any input data from the client. */ | |
367 | if (FD_ISSET(connection_in, readset)) { | |
368 | len = read(connection_in, buf, sizeof(buf)); | |
369 | if (len == 0) { | |
00e842d8 | 370 | verbose("Connection closed by %.100s", |
371 | get_remote_ipaddr()); | |
cc94bd38 | 372 | connection_closed = 1; |
373 | if (compat20) | |
374 | return; | |
2362db19 | 375 | cleanup_exit(255); |
0e73cc53 | 376 | } else if (len < 0) { |
377 | if (errno != EINTR && errno != EAGAIN) { | |
00e842d8 | 378 | verbose("Read error from remote host " |
379 | "%.100s: %.100s", | |
380 | get_remote_ipaddr(), strerror(errno)); | |
2362db19 | 381 | cleanup_exit(255); |
0e73cc53 | 382 | } |
383 | } else { | |
384 | /* Buffer any received data. */ | |
385 | packet_process_incoming(buf, len); | |
5260325f | 386 | } |
5260325f | 387 | } |
e78a59f5 | 388 | if (compat20) |
389 | return; | |
390 | ||
5260325f | 391 | /* Read and buffer any available stdout data from the program. */ |
392 | if (!fdout_eof && FD_ISSET(fdout, readset)) { | |
ea8c44d9 | 393 | errno = 0; |
5260325f | 394 | len = read(fdout, buf, sizeof(buf)); |
0e73cc53 | 395 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) { |
396 | /* do nothing */ | |
24a87055 | 397 | #ifndef PTY_ZEROREAD |
0e73cc53 | 398 | } else if (len <= 0) { |
ea8c44d9 | 399 | #else |
9c04d67d | 400 | } else if ((!isatty(fdout) && len <= 0) || |
401 | (isatty(fdout) && (len < 0 || (len == 0 && errno != 0)))) { | |
ea8c44d9 | 402 | #endif |
5260325f | 403 | fdout_eof = 1; |
0e73cc53 | 404 | } else { |
5260325f | 405 | buffer_append(&stdout_buffer, buf, len); |
406 | fdout_bytes += len; | |
407 | } | |
408 | } | |
409 | /* Read and buffer any available stderr data from the program. */ | |
410 | if (!fderr_eof && FD_ISSET(fderr, readset)) { | |
ea8c44d9 | 411 | errno = 0; |
5260325f | 412 | len = read(fderr, buf, sizeof(buf)); |
0e73cc53 | 413 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) { |
414 | /* do nothing */ | |
24a87055 | 415 | #ifndef PTY_ZEROREAD |
0e73cc53 | 416 | } else if (len <= 0) { |
ea8c44d9 | 417 | #else |
9c04d67d | 418 | } else if ((!isatty(fderr) && len <= 0) || |
419 | (isatty(fderr) && (len < 0 || (len == 0 && errno != 0)))) { | |
ea8c44d9 | 420 | #endif |
5260325f | 421 | fderr_eof = 1; |
0e73cc53 | 422 | } else { |
5260325f | 423 | buffer_append(&stderr_buffer, buf, len); |
0e73cc53 | 424 | } |
5260325f | 425 | } |
426 | } | |
8efc0c15 | 427 | |
5260325f | 428 | /* |
429 | * Sends data from internal buffers to client program stdin. | |
430 | */ | |
396c147e | 431 | static void |
b476adfa | 432 | process_output(fd_set *writeset) |
8efc0c15 | 433 | { |
4ef922e3 | 434 | struct termios tio; |
780a9951 | 435 | u_char *data; |
436 | u_int dlen; | |
5260325f | 437 | int len; |
438 | ||
439 | /* Write buffered data to program stdin. */ | |
e78a59f5 | 440 | if (!compat20 && fdin != -1 && FD_ISSET(fdin, writeset)) { |
780a9951 | 441 | data = buffer_ptr(&stdin_buffer); |
442 | dlen = buffer_len(&stdin_buffer); | |
443 | len = write(fdin, data, dlen); | |
0e73cc53 | 444 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) { |
445 | /* do nothing */ | |
446 | } else if (len <= 0) { | |
7368a6c8 | 447 | if (fdin != fdout) |
5260325f | 448 | close(fdin); |
449 | else | |
450 | shutdown(fdin, SHUT_WR); /* We will no longer send. */ | |
5260325f | 451 | fdin = -1; |
452 | } else { | |
4ef922e3 | 453 | /* Successful write. */ |
780a9951 | 454 | if (fdin_is_tty && dlen >= 1 && data[0] != '\r' && |
455 | tcgetattr(fdin, &tio) == 0 && | |
0ae4fe1d | 456 | !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) { |
62da27dd | 457 | /* |
458 | * Simulate echo to reduce the impact of | |
459 | * traffic analysis | |
460 | */ | |
95ce5599 | 461 | packet_send_ignore(len); |
4ef922e3 | 462 | packet_send(); |
463 | } | |
464 | /* Consume the data from the buffer. */ | |
5260325f | 465 | buffer_consume(&stdin_buffer, len); |
466 | /* Update the count of bytes written to the program. */ | |
467 | stdin_bytes += len; | |
468 | } | |
8efc0c15 | 469 | } |
5260325f | 470 | /* Send any buffered packet data to the client. */ |
471 | if (FD_ISSET(connection_out, writeset)) | |
472 | packet_write_poll(); | |
8efc0c15 | 473 | } |
474 | ||
5260325f | 475 | /* |
476 | * Wait until all buffered output has been sent to the client. | |
477 | * This is used when the program terminates. | |
478 | */ | |
396c147e | 479 | static void |
5ca51e19 | 480 | drain_output(void) |
8efc0c15 | 481 | { |
5260325f | 482 | /* Send any buffered stdout data to the client. */ |
483 | if (buffer_len(&stdout_buffer) > 0) { | |
484 | packet_start(SSH_SMSG_STDOUT_DATA); | |
485 | packet_put_string(buffer_ptr(&stdout_buffer), | |
486 | buffer_len(&stdout_buffer)); | |
487 | packet_send(); | |
488 | /* Update the count of sent bytes. */ | |
489 | stdout_bytes += buffer_len(&stdout_buffer); | |
490 | } | |
491 | /* Send any buffered stderr data to the client. */ | |
492 | if (buffer_len(&stderr_buffer) > 0) { | |
493 | packet_start(SSH_SMSG_STDERR_DATA); | |
494 | packet_put_string(buffer_ptr(&stderr_buffer), | |
495 | buffer_len(&stderr_buffer)); | |
496 | packet_send(); | |
497 | /* Update the count of sent bytes. */ | |
498 | stderr_bytes += buffer_len(&stderr_buffer); | |
499 | } | |
500 | /* Wait until all buffered data has been written to the client. */ | |
501 | packet_write_wait(); | |
8efc0c15 | 502 | } |
503 | ||
396c147e | 504 | static void |
5ca51e19 | 505 | process_buffered_input_packets(void) |
7368a6c8 | 506 | { |
7a37c112 | 507 | dispatch_run(DISPATCH_NONBLOCK, NULL, compat20 ? xxx_kex : NULL); |
7368a6c8 | 508 | } |
509 | ||
5260325f | 510 | /* |
511 | * Performs the interactive session. This handles data transmission between | |
512 | * the client and the program. Note that the notion of stdin, stdout, and | |
513 | * stderr in this function is sort of reversed: this function writes to | |
514 | * stdin (of the child program), and reads from stdout and stderr (of the | |
515 | * child program). | |
516 | */ | |
6ae2364d | 517 | void |
9da5c3c9 | 518 | server_loop(pid_t pid, int fdin_arg, int fdout_arg, int fderr_arg) |
8efc0c15 | 519 | { |
39929cdb | 520 | fd_set *readset = NULL, *writeset = NULL; |
9a995072 | 521 | int max_fd = 0; |
522 | u_int nalloc = 0; | |
9da5c3c9 | 523 | int wait_status; /* Status returned by wait(). */ |
524 | pid_t wait_pid; /* pid returned by wait(). */ | |
5260325f | 525 | int waiting_termination = 0; /* Have displayed waiting close message. */ |
1e3b8b07 | 526 | u_int max_time_milliseconds; |
527 | u_int previous_stdout_buffer_bytes; | |
528 | u_int stdout_buffer_bytes; | |
5260325f | 529 | int type; |
530 | ||
531 | debug("Entering interactive session."); | |
532 | ||
533 | /* Initialize the SIGCHLD kludge. */ | |
5260325f | 534 | child_terminated = 0; |
42ad0eec | 535 | mysignal(SIGCHLD, sigchld_handler); |
5260325f | 536 | |
0bbbf2a4 | 537 | if (!use_privsep) { |
538 | signal(SIGTERM, sigterm_handler); | |
539 | signal(SIGINT, sigterm_handler); | |
540 | signal(SIGQUIT, sigterm_handler); | |
541 | } | |
542 | ||
5260325f | 543 | /* Initialize our global variables. */ |
544 | fdin = fdin_arg; | |
545 | fdout = fdout_arg; | |
546 | fderr = fderr_arg; | |
0e73cc53 | 547 | |
548 | /* nonblocking IO */ | |
549 | set_nonblock(fdin); | |
550 | set_nonblock(fdout); | |
ff873e98 | 551 | /* we don't have stderr for interactive terminal sessions, see below */ |
552 | if (fderr != -1) | |
553 | set_nonblock(fderr); | |
0e73cc53 | 554 | |
e68225b2 | 555 | if (!(datafellows & SSH_BUG_IGNOREMSG) && isatty(fdin)) |
556 | fdin_is_tty = 1; | |
557 | ||
5260325f | 558 | connection_in = packet_get_connection_in(); |
559 | connection_out = packet_get_connection_out(); | |
560 | ||
a10be357 | 561 | notify_setup(); |
562 | ||
5260325f | 563 | previous_stdout_buffer_bytes = 0; |
564 | ||
565 | /* Set approximate I/O buffer size. */ | |
566 | if (packet_is_interactive()) | |
567 | buffer_high = 4096; | |
568 | else | |
569 | buffer_high = 64 * 1024; | |
570 | ||
489aa2e9 | 571 | #if 0 |
5260325f | 572 | /* Initialize max_fd to the maximum of the known file descriptors. */ |
489aa2e9 | 573 | max_fd = MAX(connection_in, connection_out); |
574 | max_fd = MAX(max_fd, fdin); | |
575 | max_fd = MAX(max_fd, fdout); | |
39929cdb | 576 | if (fderr != -1) |
577 | max_fd = MAX(max_fd, fderr); | |
489aa2e9 | 578 | #endif |
5260325f | 579 | |
580 | /* Initialize Initialize buffers. */ | |
581 | buffer_init(&stdin_buffer); | |
582 | buffer_init(&stdout_buffer); | |
583 | buffer_init(&stderr_buffer); | |
584 | ||
aa3378df | 585 | /* |
586 | * If we have no separate fderr (which is the case when we have a pty | |
587 | * - there we cannot make difference between data sent to stdout and | |
588 | * stderr), indicate that we have seen an EOF from stderr. This way | |
7b9b0103 | 589 | * we don't need to check the descriptor everywhere. |
aa3378df | 590 | */ |
5260325f | 591 | if (fderr == -1) |
592 | fderr_eof = 1; | |
593 | ||
7368a6c8 | 594 | server_init_dispatch(); |
595 | ||
5260325f | 596 | /* Main loop of the server for the interactive session mode. */ |
597 | for (;;) { | |
5260325f | 598 | |
599 | /* Process buffered packets from the client. */ | |
600 | process_buffered_input_packets(); | |
601 | ||
aa3378df | 602 | /* |
603 | * If we have received eof, and there is no more pending | |
604 | * input data, cause a real eof by closing fdin. | |
605 | */ | |
5260325f | 606 | if (stdin_eof && fdin != -1 && buffer_len(&stdin_buffer) == 0) { |
7368a6c8 | 607 | if (fdin != fdout) |
5260325f | 608 | close(fdin); |
609 | else | |
610 | shutdown(fdin, SHUT_WR); /* We will no longer send. */ | |
5260325f | 611 | fdin = -1; |
612 | } | |
aa3378df | 613 | /* Make packets from buffered stderr data to send to the client. */ |
5260325f | 614 | make_packets_from_stderr_data(); |
615 | ||
aa3378df | 616 | /* |
617 | * Make packets from buffered stdout data to send to the | |
618 | * client. If there is very little to send, this arranges to | |
619 | * not send them now, but to wait a short while to see if we | |
620 | * are getting more data. This is necessary, as some systems | |
621 | * wake up readers from a pty after each separate character. | |
622 | */ | |
5260325f | 623 | max_time_milliseconds = 0; |
624 | stdout_buffer_bytes = buffer_len(&stdout_buffer); | |
625 | if (stdout_buffer_bytes != 0 && stdout_buffer_bytes < 256 && | |
626 | stdout_buffer_bytes != previous_stdout_buffer_bytes) { | |
627 | /* try again after a while */ | |
628 | max_time_milliseconds = 10; | |
629 | } else { | |
630 | /* Send it now. */ | |
631 | make_packets_from_stdout_data(); | |
632 | } | |
633 | previous_stdout_buffer_bytes = buffer_len(&stdout_buffer); | |
634 | ||
635 | /* Send channel data to the client. */ | |
636 | if (packet_not_very_much_data_to_write()) | |
637 | channel_output_poll(); | |
638 | ||
aa3378df | 639 | /* |
640 | * Bail out of the loop if the program has closed its output | |
641 | * descriptors, and we have no more data to send to the | |
642 | * client, and there is no pending buffered data. | |
643 | */ | |
7062c40f | 644 | if (fdout_eof && fderr_eof && !packet_have_data_to_write() && |
645 | buffer_len(&stdout_buffer) == 0 && buffer_len(&stderr_buffer) == 0) { | |
5260325f | 646 | if (!channel_still_open()) |
7368a6c8 | 647 | break; |
5260325f | 648 | if (!waiting_termination) { |
649 | const char *s = "Waiting for forwarded connections to terminate...\r\n"; | |
650 | char *cp; | |
651 | waiting_termination = 1; | |
652 | buffer_append(&stderr_buffer, s, strlen(s)); | |
653 | ||
654 | /* Display list of open channels. */ | |
655 | cp = channel_open_message(); | |
656 | buffer_append(&stderr_buffer, cp, strlen(cp)); | |
657 | xfree(cp); | |
658 | } | |
659 | } | |
489aa2e9 | 660 | max_fd = MAX(connection_in, connection_out); |
661 | max_fd = MAX(max_fd, fdin); | |
662 | max_fd = MAX(max_fd, fdout); | |
663 | max_fd = MAX(max_fd, fderr); | |
a10be357 | 664 | max_fd = MAX(max_fd, notify_pipe[0]); |
489aa2e9 | 665 | |
5260325f | 666 | /* Sleep in select() until we can do something. */ |
39929cdb | 667 | wait_until_can_do_something(&readset, &writeset, &max_fd, |
489aa2e9 | 668 | &nalloc, max_time_milliseconds); |
5260325f | 669 | |
0bbbf2a4 | 670 | if (received_sigterm) { |
671 | logit("Exiting on signal %d", received_sigterm); | |
672 | /* Clean up sessions, utmp, etc. */ | |
673 | cleanup_exit(255); | |
674 | } | |
675 | ||
5260325f | 676 | /* Process any channel events. */ |
39929cdb | 677 | channel_after_select(readset, writeset); |
5260325f | 678 | |
679 | /* Process input from the client and from program stdout/stderr. */ | |
39929cdb | 680 | process_input(readset); |
5260325f | 681 | |
682 | /* Process output to the client and to program stdin. */ | |
39929cdb | 683 | process_output(writeset); |
8efc0c15 | 684 | } |
39929cdb | 685 | if (readset) |
686 | xfree(readset); | |
687 | if (writeset) | |
688 | xfree(writeset); | |
8efc0c15 | 689 | |
5260325f | 690 | /* Cleanup and termination code. */ |
8efc0c15 | 691 | |
5260325f | 692 | /* Wait until all output has been sent to the client. */ |
693 | drain_output(); | |
8efc0c15 | 694 | |
5260325f | 695 | debug("End of interactive session; stdin %ld, stdout (read %ld, sent %ld), stderr %ld bytes.", |
184eed6a | 696 | stdin_bytes, fdout_bytes, stdout_bytes, stderr_bytes); |
8efc0c15 | 697 | |
5260325f | 698 | /* Free and clear the buffers. */ |
699 | buffer_free(&stdin_buffer); | |
700 | buffer_free(&stdout_buffer); | |
701 | buffer_free(&stderr_buffer); | |
8efc0c15 | 702 | |
5260325f | 703 | /* Close the file descriptors. */ |
704 | if (fdout != -1) | |
705 | close(fdout); | |
706 | fdout = -1; | |
707 | fdout_eof = 1; | |
708 | if (fderr != -1) | |
709 | close(fderr); | |
710 | fderr = -1; | |
711 | fderr_eof = 1; | |
712 | if (fdin != -1) | |
713 | close(fdin); | |
714 | fdin = -1; | |
715 | ||
d6746a0b | 716 | channel_free_all(); |
5260325f | 717 | |
5260325f | 718 | /* We no longer want our SIGCHLD handler to be called. */ |
42ad0eec | 719 | mysignal(SIGCHLD, SIG_DFL); |
5260325f | 720 | |
8c38e88b | 721 | while ((wait_pid = waitpid(-1, &wait_status, 0)) < 0) |
722 | if (errno != EINTR) | |
723 | packet_disconnect("wait: %.100s", strerror(errno)); | |
724 | if (wait_pid != pid) | |
c457707e | 725 | error("Strange, wait returned pid %ld, expected %ld", |
726 | (long)wait_pid, (long)pid); | |
c9130033 | 727 | |
5260325f | 728 | /* Check if it exited normally. */ |
729 | if (WIFEXITED(wait_status)) { | |
730 | /* Yes, normal exit. Get exit status and send it to the client. */ | |
731 | debug("Command exited with status %d.", WEXITSTATUS(wait_status)); | |
732 | packet_start(SSH_SMSG_EXITSTATUS); | |
733 | packet_put_int(WEXITSTATUS(wait_status)); | |
734 | packet_send(); | |
735 | packet_write_wait(); | |
736 | ||
aa3378df | 737 | /* |
738 | * Wait for exit confirmation. Note that there might be | |
739 | * other packets coming before it; however, the program has | |
740 | * already died so we just ignore them. The client is | |
741 | * supposed to respond with the confirmation when it receives | |
742 | * the exit status. | |
743 | */ | |
5260325f | 744 | do { |
54a5250f | 745 | type = packet_read(); |
5260325f | 746 | } |
747 | while (type != SSH_CMSG_EXIT_CONFIRMATION); | |
748 | ||
749 | debug("Received exit confirmation."); | |
750 | return; | |
751 | } | |
752 | /* Check if the program terminated due to a signal. */ | |
753 | if (WIFSIGNALED(wait_status)) | |
754 | packet_disconnect("Command terminated on signal %d.", | |
755 | WTERMSIG(wait_status)); | |
756 | ||
757 | /* Some weird exit cause. Just exit. */ | |
758 | packet_disconnect("wait returned status %04x.", wait_status); | |
759 | /* NOTREACHED */ | |
760 | } | |
7368a6c8 | 761 | |
418e724c | 762 | static void |
763 | collect_children(void) | |
764 | { | |
765 | pid_t pid; | |
766 | sigset_t oset, nset; | |
767 | int status; | |
768 | ||
769 | /* block SIGCHLD while we check for dead children */ | |
770 | sigemptyset(&nset); | |
771 | sigaddset(&nset, SIGCHLD); | |
772 | sigprocmask(SIG_BLOCK, &nset, &oset); | |
773 | if (child_terminated) { | |
140000b4 | 774 | debug("Received SIGCHLD."); |
8c38e88b | 775 | while ((pid = waitpid(-1, &status, WNOHANG)) > 0 || |
776 | (pid < 0 && errno == EINTR)) | |
777 | if (pid > 0) | |
778 | session_close_by_pid(pid, status); | |
418e724c | 779 | child_terminated = 0; |
780 | } | |
781 | sigprocmask(SIG_SETMASK, &oset, NULL); | |
782 | } | |
783 | ||
6ae2364d | 784 | void |
57156994 | 785 | server_loop2(Authctxt *authctxt) |
e78a59f5 | 786 | { |
39929cdb | 787 | fd_set *readset = NULL, *writeset = NULL; |
418e724c | 788 | int rekeying = 0, max_fd, nalloc = 0; |
e78a59f5 | 789 | |
790 | debug("Entering interactive session for SSH2."); | |
791 | ||
c9130033 | 792 | mysignal(SIGCHLD, sigchld_handler); |
e78a59f5 | 793 | child_terminated = 0; |
794 | connection_in = packet_get_connection_in(); | |
795 | connection_out = packet_get_connection_out(); | |
39929cdb | 796 | |
0bbbf2a4 | 797 | if (!use_privsep) { |
798 | signal(SIGTERM, sigterm_handler); | |
799 | signal(SIGINT, sigterm_handler); | |
800 | signal(SIGQUIT, sigterm_handler); | |
801 | } | |
802 | ||
a10be357 | 803 | notify_setup(); |
804 | ||
39929cdb | 805 | max_fd = MAX(connection_in, connection_out); |
a10be357 | 806 | max_fd = MAX(max_fd, notify_pipe[0]); |
807 | ||
e78a59f5 | 808 | server_init_dispatch(); |
809 | ||
810 | for (;;) { | |
811 | process_buffered_input_packets(); | |
bbb4cc1b | 812 | |
cd332296 | 813 | rekeying = (xxx_kex != NULL && !xxx_kex->done); |
bbb4cc1b | 814 | |
bbb4cc1b | 815 | if (!rekeying && packet_not_very_much_data_to_write()) |
e78a59f5 | 816 | channel_output_poll(); |
bbb4cc1b | 817 | wait_until_can_do_something(&readset, &writeset, &max_fd, |
489aa2e9 | 818 | &nalloc, 0); |
d5f24f94 | 819 | |
0bbbf2a4 | 820 | if (received_sigterm) { |
821 | logit("Exiting on signal %d", received_sigterm); | |
822 | /* Clean up sessions, utmp, etc. */ | |
823 | cleanup_exit(255); | |
824 | } | |
825 | ||
418e724c | 826 | collect_children(); |
ffd7b36b | 827 | if (!rekeying) { |
bbb4cc1b | 828 | channel_after_select(readset, writeset); |
ffd7b36b | 829 | if (packet_need_rekeying()) { |
830 | debug("need rekeying"); | |
831 | xxx_kex->done = 0; | |
832 | kex_send_kexinit(xxx_kex); | |
833 | } | |
834 | } | |
39929cdb | 835 | process_input(readset); |
cc94bd38 | 836 | if (connection_closed) |
837 | break; | |
39929cdb | 838 | process_output(writeset); |
e78a59f5 | 839 | } |
418e724c | 840 | collect_children(); |
841 | ||
39929cdb | 842 | if (readset) |
843 | xfree(readset); | |
844 | if (writeset) | |
845 | xfree(writeset); | |
846 | ||
d5f24f94 | 847 | /* free all channels, no more reads and writes */ |
848 | channel_free_all(); | |
5b5d170c | 849 | |
418e724c | 850 | /* free remaining sessions, e.g. remove wtmp entries */ |
1853d1ef | 851 | session_destroy_all(NULL); |
e78a59f5 | 852 | } |
853 | ||
396c147e | 854 | static void |
95ae2076 | 855 | server_input_keep_alive(int type, u_int32_t seq, void *ctxt) |
3ffc6336 | 856 | { |
95ae2076 | 857 | debug("Got %d/%u for keepalive", type, seq); |
184eed6a | 858 | /* |
39aefe7b | 859 | * reset timeout, since we got a sane answer from the client. |
3ffc6336 | 860 | * even if this was generated by something other than |
861 | * the bogus CHANNEL_REQUEST we send for keepalives. | |
862 | */ | |
184eed6a | 863 | client_alive_timeouts = 0; |
3ffc6336 | 864 | } |
865 | ||
396c147e | 866 | static void |
7819b5c3 | 867 | server_input_stdin_data(int type, u_int32_t seq, void *ctxt) |
7368a6c8 | 868 | { |
869 | char *data; | |
1e3b8b07 | 870 | u_int data_len; |
7368a6c8 | 871 | |
872 | /* Stdin data from the client. Append it to the buffer. */ | |
873 | /* Ignore any data if the client has closed stdin. */ | |
874 | if (fdin == -1) | |
875 | return; | |
876 | data = packet_get_string(&data_len); | |
95500969 | 877 | packet_check_eom(); |
7368a6c8 | 878 | buffer_append(&stdin_buffer, data, data_len); |
879 | memset(data, 0, data_len); | |
880 | xfree(data); | |
881 | } | |
882 | ||
396c147e | 883 | static void |
7819b5c3 | 884 | server_input_eof(int type, u_int32_t seq, void *ctxt) |
7368a6c8 | 885 | { |
886 | /* | |
887 | * Eof from the client. The stdin descriptor to the | |
888 | * program will be closed when all buffered data has | |
889 | * drained. | |
890 | */ | |
891 | debug("EOF received for stdin."); | |
95500969 | 892 | packet_check_eom(); |
7368a6c8 | 893 | stdin_eof = 1; |
894 | } | |
895 | ||
396c147e | 896 | static void |
7819b5c3 | 897 | server_input_window_size(int type, u_int32_t seq, void *ctxt) |
7368a6c8 | 898 | { |
148de80c | 899 | u_int row = packet_get_int(); |
900 | u_int col = packet_get_int(); | |
901 | u_int xpixel = packet_get_int(); | |
902 | u_int ypixel = packet_get_int(); | |
7368a6c8 | 903 | |
904 | debug("Window change received."); | |
95500969 | 905 | packet_check_eom(); |
7368a6c8 | 906 | if (fdin != -1) |
907 | pty_change_window_size(fdin, row, col, xpixel, ypixel); | |
908 | } | |
909 | ||
396c147e | 910 | static Channel * |
43f7a4b8 | 911 | server_request_direct_tcpip(void) |
e78a59f5 | 912 | { |
719fc62f | 913 | Channel *c; |
914 | int sock; | |
6ae2364d | 915 | char *target, *originator; |
916 | int target_port, originator_port; | |
e78a59f5 | 917 | |
6ae2364d | 918 | target = packet_get_string(NULL); |
919 | target_port = packet_get_int(); | |
e78a59f5 | 920 | originator = packet_get_string(NULL); |
921 | originator_port = packet_get_int(); | |
95500969 | 922 | packet_check_eom(); |
71276795 | 923 | |
fa08c86b | 924 | debug("server_request_direct_tcpip: originator %s port %d, target %s port %d", |
4e2e5cfd | 925 | originator, originator_port, target, target_port); |
38c295d6 | 926 | |
e78a59f5 | 927 | /* XXX check permission */ |
6ae2364d | 928 | sock = channel_connect_to(target, target_port); |
929 | xfree(target); | |
e78a59f5 | 930 | xfree(originator); |
931 | if (sock < 0) | |
fa08c86b | 932 | return NULL; |
43f7a4b8 | 933 | c = channel_new("direct-tcpip", SSH_CHANNEL_CONNECTING, |
bcbf86ec | 934 | sock, sock, -1, CHAN_TCP_WINDOW_DEFAULT, |
0d942eff | 935 | CHAN_TCP_PACKET_DEFAULT, 0, "direct-tcpip", 1); |
719fc62f | 936 | return c; |
fa08c86b | 937 | } |
938 | ||
d20f3c9e | 939 | static Channel * |
940 | server_request_tun(void) | |
941 | { | |
942 | Channel *c = NULL; | |
a4f24bf8 | 943 | int mode, tun; |
944 | int sock; | |
d20f3c9e | 945 | |
a4f24bf8 | 946 | mode = packet_get_int(); |
947 | switch (mode) { | |
948 | case SSH_TUNMODE_POINTOPOINT: | |
949 | case SSH_TUNMODE_ETHERNET: | |
950 | break; | |
951 | default: | |
952 | packet_send_debug("Unsupported tunnel device mode."); | |
953 | return NULL; | |
954 | } | |
955 | if ((options.permit_tun & mode) == 0) { | |
956 | packet_send_debug("Server has rejected tunnel device " | |
957 | "forwarding"); | |
d20f3c9e | 958 | return NULL; |
959 | } | |
960 | ||
961 | tun = packet_get_int(); | |
a2b1748a | 962 | if (forced_tun_device != -1) { |
3efa8ea9 | 963 | if (tun != SSH_TUNID_ANY && forced_tun_device != tun) |
d20f3c9e | 964 | goto done; |
965 | tun = forced_tun_device; | |
966 | } | |
a4f24bf8 | 967 | sock = tun_open(tun, mode); |
d20f3c9e | 968 | if (sock < 0) |
969 | goto done; | |
970 | c = channel_new("tun", SSH_CHANNEL_OPEN, sock, sock, -1, | |
971 | CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, "tun", 1); | |
972 | c->datagram = 1; | |
e914f53a | 973 | #if defined(SSH_TUN_FILTER) |
974 | if (mode == SSH_TUNMODE_POINTOPOINT) | |
975 | channel_register_filter(c->self, sys_tun_infilter, | |
976 | sys_tun_outfilter); | |
977 | #endif | |
d20f3c9e | 978 | |
979 | done: | |
980 | if (c == NULL) | |
981 | packet_send_debug("Failed to open the tunnel device."); | |
982 | return c; | |
983 | } | |
984 | ||
396c147e | 985 | static Channel * |
43f7a4b8 | 986 | server_request_session(void) |
fa08c86b | 987 | { |
719fc62f | 988 | Channel *c; |
fa08c86b | 989 | |
990 | debug("input_session_request"); | |
95500969 | 991 | packet_check_eom(); |
fa08c86b | 992 | /* |
993 | * A server session has no fd to read or write until a | |
994 | * CHANNEL_REQUEST for a shell is made, so we set the type to | |
995 | * SSH_CHANNEL_LARVAL. Additionally, a callback for handling all | |
996 | * CHANNEL_REQUEST messages is registered. | |
997 | */ | |
43f7a4b8 | 998 | c = channel_new("session", SSH_CHANNEL_LARVAL, |
719fc62f | 999 | -1, -1, -1, /*window size*/0, CHAN_SES_PACKET_DEFAULT, |
0d942eff | 1000 | 0, "server-session", 1); |
2362db19 | 1001 | if (session_open(the_authctxt, c->self) != 1) { |
719fc62f | 1002 | debug("session open failed, free channel %d", c->self); |
1003 | channel_free(c); | |
1004 | return NULL; | |
fa08c86b | 1005 | } |
8cd0437d | 1006 | channel_register_cleanup(c->self, session_close_by_channel, 0); |
719fc62f | 1007 | return c; |
e78a59f5 | 1008 | } |
1009 | ||
396c147e | 1010 | static void |
7819b5c3 | 1011 | server_input_channel_open(int type, u_int32_t seq, void *ctxt) |
e78a59f5 | 1012 | { |
1013 | Channel *c = NULL; | |
1014 | char *ctype; | |
e78a59f5 | 1015 | int rchan; |
f91d9a89 | 1016 | u_int rmaxpack, rwindow, len; |
e78a59f5 | 1017 | |
1018 | ctype = packet_get_string(&len); | |
1019 | rchan = packet_get_int(); | |
1020 | rwindow = packet_get_int(); | |
1021 | rmaxpack = packet_get_int(); | |
1022 | ||
188adeb2 | 1023 | debug("server_input_channel_open: ctype %s rchan %d win %d max %d", |
e78a59f5 | 1024 | ctype, rchan, rwindow, rmaxpack); |
1025 | ||
1026 | if (strcmp(ctype, "session") == 0) { | |
43f7a4b8 | 1027 | c = server_request_session(); |
e78a59f5 | 1028 | } else if (strcmp(ctype, "direct-tcpip") == 0) { |
43f7a4b8 | 1029 | c = server_request_direct_tcpip(); |
d20f3c9e | 1030 | } else if (strcmp(ctype, "tun@openssh.com") == 0) { |
1031 | c = server_request_tun(); | |
e78a59f5 | 1032 | } |
1033 | if (c != NULL) { | |
fa08c86b | 1034 | debug("server_input_channel_open: confirm %s", ctype); |
e78a59f5 | 1035 | c->remote_id = rchan; |
1036 | c->remote_window = rwindow; | |
1037 | c->remote_maxpacket = rmaxpack; | |
d18e0850 | 1038 | if (c->type != SSH_CHANNEL_CONNECTING) { |
1039 | packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1040 | packet_put_int(c->remote_id); | |
1041 | packet_put_int(c->self); | |
1042 | packet_put_int(c->local_window); | |
1043 | packet_put_int(c->local_maxpacket); | |
1044 | packet_send(); | |
1045 | } | |
e78a59f5 | 1046 | } else { |
fa08c86b | 1047 | debug("server_input_channel_open: failure %s", ctype); |
e78a59f5 | 1048 | packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE); |
1049 | packet_put_int(rchan); | |
1050 | packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED); | |
fbe90f7b | 1051 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { |
d18e0850 | 1052 | packet_put_cstring("open failed"); |
fbe90f7b | 1053 | packet_put_cstring(""); |
1054 | } | |
e78a59f5 | 1055 | packet_send(); |
1056 | } | |
1057 | xfree(ctype); | |
1058 | } | |
1059 | ||
396c147e | 1060 | static void |
7819b5c3 | 1061 | server_input_global_request(int type, u_int32_t seq, void *ctxt) |
fa08c86b | 1062 | { |
1063 | char *rtype; | |
1064 | int want_reply; | |
1065 | int success = 0; | |
1066 | ||
1067 | rtype = packet_get_string(NULL); | |
1068 | want_reply = packet_get_char(); | |
1069 | debug("server_input_global_request: rtype %s want_reply %d", rtype, want_reply); | |
2b87da3b | 1070 | |
01794848 | 1071 | /* -R style forwarding */ |
fa08c86b | 1072 | if (strcmp(rtype, "tcpip-forward") == 0) { |
1073 | struct passwd *pw; | |
1074 | char *listen_address; | |
1075 | u_short listen_port; | |
1076 | ||
2362db19 | 1077 | pw = the_authctxt->pw; |
95077f48 | 1078 | if (pw == NULL || !the_authctxt->valid) |
fdaef11e | 1079 | fatal("server_input_global_request: no/invalid user"); |
b08a39ff | 1080 | listen_address = packet_get_string(NULL); |
fa08c86b | 1081 | listen_port = (u_short)packet_get_int(); |
1082 | debug("server_input_global_request: tcpip-forward listen %s port %d", | |
1083 | listen_address, listen_port); | |
1084 | ||
1085 | /* check permissions */ | |
1086 | if (!options.allow_tcp_forwarding || | |
e6f15ed1 | 1087 | no_port_forwarding_flag |
1088 | #ifndef NO_IPPORT_RESERVED_CONCEPT | |
1089 | || (listen_port < IPPORT_RESERVED && pw->pw_uid != 0) | |
1090 | #endif | |
98c044d0 | 1091 | ) { |
fa08c86b | 1092 | success = 0; |
1093 | packet_send_debug("Server has disabled port forwarding."); | |
1094 | } else { | |
1095 | /* Start listening on the port */ | |
5641aefa | 1096 | success = channel_setup_remote_fwd_listener( |
1097 | listen_address, listen_port, options.gateway_ports); | |
fa08c86b | 1098 | } |
1099 | xfree(listen_address); | |
d740ec16 | 1100 | } else if (strcmp(rtype, "cancel-tcpip-forward") == 0) { |
1101 | char *cancel_address; | |
1102 | u_short cancel_port; | |
1103 | ||
1104 | cancel_address = packet_get_string(NULL); | |
1105 | cancel_port = (u_short)packet_get_int(); | |
1106 | debug("%s: cancel-tcpip-forward addr %s port %d", __func__, | |
1107 | cancel_address, cancel_port); | |
1108 | ||
1109 | success = channel_cancel_rport_listener(cancel_address, | |
1110 | cancel_port); | |
4113a1d7 | 1111 | xfree(cancel_address); |
fa08c86b | 1112 | } |
1113 | if (want_reply) { | |
1114 | packet_start(success ? | |
1115 | SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE); | |
1116 | packet_send(); | |
1117 | packet_write_wait(); | |
1118 | } | |
1119 | xfree(rtype); | |
1120 | } | |
a7137f6b | 1121 | |
7899c98f | 1122 | static void |
1123 | server_input_channel_req(int type, u_int32_t seq, void *ctxt) | |
1124 | { | |
1125 | Channel *c; | |
1126 | int id, reply, success = 0; | |
1127 | char *rtype; | |
1128 | ||
1129 | id = packet_get_int(); | |
1130 | rtype = packet_get_string(NULL); | |
1131 | reply = packet_get_char(); | |
1132 | ||
1133 | debug("server_input_channel_req: channel %d request %s reply %d", | |
1134 | id, rtype, reply); | |
1135 | ||
1136 | if ((c = channel_lookup(id)) == NULL) | |
1137 | packet_disconnect("server_input_channel_req: " | |
1138 | "unknown channel %d", id); | |
1139 | if (c->type == SSH_CHANNEL_LARVAL || c->type == SSH_CHANNEL_OPEN) | |
1140 | success = session_input_channel_req(c, rtype); | |
1141 | if (reply) { | |
1142 | packet_start(success ? | |
1143 | SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE); | |
1144 | packet_put_int(c->remote_id); | |
1145 | packet_send(); | |
1146 | } | |
1147 | xfree(rtype); | |
1148 | } | |
fa08c86b | 1149 | |
396c147e | 1150 | static void |
5ca51e19 | 1151 | server_init_dispatch_20(void) |
e78a59f5 | 1152 | { |
1153 | debug("server_init_dispatch_20"); | |
1154 | dispatch_init(&dispatch_protocol_error); | |
1155 | dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose); | |
1156 | dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data); | |
1157 | dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof); | |
1158 | dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data); | |
1159 | dispatch_set(SSH2_MSG_CHANNEL_OPEN, &server_input_channel_open); | |
1160 | dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation); | |
1161 | dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure); | |
7899c98f | 1162 | dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &server_input_channel_req); |
e78a59f5 | 1163 | dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust); |
fa08c86b | 1164 | dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &server_input_global_request); |
3ffc6336 | 1165 | /* client_alive */ |
95ae2076 | 1166 | dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &server_input_keep_alive); |
1167 | dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &server_input_keep_alive); | |
1168 | dispatch_set(SSH2_MSG_REQUEST_FAILURE, &server_input_keep_alive); | |
7a37c112 | 1169 | /* rekeying */ |
1170 | dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit); | |
e78a59f5 | 1171 | } |
396c147e | 1172 | static void |
5ca51e19 | 1173 | server_init_dispatch_13(void) |
7368a6c8 | 1174 | { |
1175 | debug("server_init_dispatch_13"); | |
1176 | dispatch_init(NULL); | |
1177 | dispatch_set(SSH_CMSG_EOF, &server_input_eof); | |
1178 | dispatch_set(SSH_CMSG_STDIN_DATA, &server_input_stdin_data); | |
1179 | dispatch_set(SSH_CMSG_WINDOW_SIZE, &server_input_window_size); | |
1180 | dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close); | |
1181 | dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation); | |
1182 | dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data); | |
1183 | dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation); | |
1184 | dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure); | |
1185 | dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open); | |
1186 | } | |
396c147e | 1187 | static void |
5ca51e19 | 1188 | server_init_dispatch_15(void) |
7368a6c8 | 1189 | { |
1190 | server_init_dispatch_13(); | |
1191 | debug("server_init_dispatch_15"); | |
1192 | dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof); | |
1193 | dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_oclose); | |
1194 | } | |
396c147e | 1195 | static void |
5ca51e19 | 1196 | server_init_dispatch(void) |
7368a6c8 | 1197 | { |
e78a59f5 | 1198 | if (compat20) |
1199 | server_init_dispatch_20(); | |
1200 | else if (compat13) | |
7368a6c8 | 1201 | server_init_dispatch_13(); |
1202 | else | |
1203 | server_init_dispatch_15(); | |
1204 | } |