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