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1 | /* $OpenBSD: clientloop.c,v 1.213 2009/07/05 19:28:33 stevesk Exp $ */ | |
2 | /* | |
3 | * Author: Tatu Ylonen <ylo@cs.hut.fi> | |
4 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland | |
5 | * All rights reserved | |
6 | * The main loop for the interactive session (client side). | |
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 | * | |
14 | * | |
15 | * Copyright (c) 1999 Theo de Raadt. All rights reserved. | |
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. | |
36 | * | |
37 | * | |
38 | * SSH2 support added by Markus Friedl. | |
39 | * Copyright (c) 1999, 2000, 2001 Markus Friedl. All rights reserved. | |
40 | * | |
41 | * Redistribution and use in source and binary forms, with or without | |
42 | * modification, are permitted provided that the following conditions | |
43 | * are met: | |
44 | * 1. Redistributions of source code must retain the above copyright | |
45 | * notice, this list of conditions and the following disclaimer. | |
46 | * 2. Redistributions in binary form must reproduce the above copyright | |
47 | * notice, this list of conditions and the following disclaimer in the | |
48 | * documentation and/or other materials provided with the distribution. | |
49 | * | |
50 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR | |
51 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES | |
52 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. | |
53 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, | |
54 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | |
55 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | |
56 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | |
57 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
58 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | |
59 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
60 | */ | |
61 | ||
62 | #include "includes.h" | |
63 | ||
64 | #include <sys/types.h> | |
65 | #include <sys/ioctl.h> | |
66 | #include <sys/param.h> | |
67 | #ifdef HAVE_SYS_STAT_H | |
68 | # include <sys/stat.h> | |
69 | #endif | |
70 | #ifdef HAVE_SYS_TIME_H | |
71 | # include <sys/time.h> | |
72 | #endif | |
73 | #include <sys/socket.h> | |
74 | ||
75 | #include <ctype.h> | |
76 | #include <errno.h> | |
77 | #ifdef HAVE_PATHS_H | |
78 | #include <paths.h> | |
79 | #endif | |
80 | #include <signal.h> | |
81 | #include <stdarg.h> | |
82 | #include <stdio.h> | |
83 | #include <stdlib.h> | |
84 | #include <string.h> | |
85 | #include <termios.h> | |
86 | #include <pwd.h> | |
87 | #include <unistd.h> | |
88 | ||
89 | #include "openbsd-compat/sys-queue.h" | |
90 | #include "xmalloc.h" | |
91 | #include "ssh.h" | |
92 | #include "ssh1.h" | |
93 | #include "ssh2.h" | |
94 | #include "packet.h" | |
95 | #include "buffer.h" | |
96 | #include "compat.h" | |
97 | #include "channels.h" | |
98 | #include "dispatch.h" | |
99 | #include "key.h" | |
100 | #include "cipher.h" | |
101 | #include "kex.h" | |
102 | #include "log.h" | |
103 | #include "readconf.h" | |
104 | #include "clientloop.h" | |
105 | #include "sshconnect.h" | |
106 | #include "authfd.h" | |
107 | #include "atomicio.h" | |
108 | #include "sshpty.h" | |
109 | #include "misc.h" | |
110 | #include "match.h" | |
111 | #include "msg.h" | |
112 | #include "roaming.h" | |
113 | ||
114 | /* import options */ | |
115 | extern Options options; | |
116 | ||
117 | /* Flag indicating that stdin should be redirected from /dev/null. */ | |
118 | extern int stdin_null_flag; | |
119 | ||
120 | /* Flag indicating that no shell has been requested */ | |
121 | extern int no_shell_flag; | |
122 | ||
123 | /* Control socket */ | |
124 | extern int muxserver_sock; | |
125 | ||
126 | /* | |
127 | * Name of the host we are connecting to. This is the name given on the | |
128 | * command line, or the HostName specified for the user-supplied name in a | |
129 | * configuration file. | |
130 | */ | |
131 | extern char *host; | |
132 | ||
133 | /* | |
134 | * Flag to indicate that we have received a window change signal which has | |
135 | * not yet been processed. This will cause a message indicating the new | |
136 | * window size to be sent to the server a little later. This is volatile | |
137 | * because this is updated in a signal handler. | |
138 | */ | |
139 | static volatile sig_atomic_t received_window_change_signal = 0; | |
140 | static volatile sig_atomic_t received_signal = 0; | |
141 | ||
142 | /* Flag indicating whether the user's terminal is in non-blocking mode. */ | |
143 | static int in_non_blocking_mode = 0; | |
144 | ||
145 | /* Common data for the client loop code. */ | |
146 | static volatile sig_atomic_t quit_pending; /* Set non-zero to quit the loop. */ | |
147 | static int escape_char1; /* Escape character. (proto1 only) */ | |
148 | static int escape_pending1; /* Last character was an escape (proto1 only) */ | |
149 | static int last_was_cr; /* Last character was a newline. */ | |
150 | static int exit_status; /* Used to store the command exit status. */ | |
151 | static int stdin_eof; /* EOF has been encountered on stderr. */ | |
152 | static Buffer stdin_buffer; /* Buffer for stdin data. */ | |
153 | static Buffer stdout_buffer; /* Buffer for stdout data. */ | |
154 | static Buffer stderr_buffer; /* Buffer for stderr data. */ | |
155 | static u_int buffer_high;/* Soft max buffer size. */ | |
156 | static int connection_in; /* Connection to server (input). */ | |
157 | static int connection_out; /* Connection to server (output). */ | |
158 | static int need_rekeying; /* Set to non-zero if rekeying is requested. */ | |
159 | static int session_closed = 0; /* In SSH2: login session closed. */ | |
160 | ||
161 | static void client_init_dispatch(void); | |
162 | int session_ident = -1; | |
163 | ||
164 | /* Track escape per proto2 channel */ | |
165 | struct escape_filter_ctx { | |
166 | int escape_pending; | |
167 | int escape_char; | |
168 | }; | |
169 | ||
170 | /* Context for channel confirmation replies */ | |
171 | struct channel_reply_ctx { | |
172 | const char *request_type; | |
173 | int id, do_close; | |
174 | }; | |
175 | ||
176 | /* Global request success/failure callbacks */ | |
177 | struct global_confirm { | |
178 | TAILQ_ENTRY(global_confirm) entry; | |
179 | global_confirm_cb *cb; | |
180 | void *ctx; | |
181 | int ref_count; | |
182 | }; | |
183 | TAILQ_HEAD(global_confirms, global_confirm); | |
184 | static struct global_confirms global_confirms = | |
185 | TAILQ_HEAD_INITIALIZER(global_confirms); | |
186 | ||
187 | /*XXX*/ | |
188 | extern Kex *xxx_kex; | |
189 | ||
190 | void ssh_process_session2_setup(int, int, int, Buffer *); | |
191 | ||
192 | /* Restores stdin to blocking mode. */ | |
193 | ||
194 | static void | |
195 | leave_non_blocking(void) | |
196 | { | |
197 | if (in_non_blocking_mode) { | |
198 | unset_nonblock(fileno(stdin)); | |
199 | in_non_blocking_mode = 0; | |
200 | } | |
201 | } | |
202 | ||
203 | /* Puts stdin terminal in non-blocking mode. */ | |
204 | ||
205 | static void | |
206 | enter_non_blocking(void) | |
207 | { | |
208 | in_non_blocking_mode = 1; | |
209 | set_nonblock(fileno(stdin)); | |
210 | } | |
211 | ||
212 | /* | |
213 | * Signal handler for the window change signal (SIGWINCH). This just sets a | |
214 | * flag indicating that the window has changed. | |
215 | */ | |
216 | /*ARGSUSED */ | |
217 | static void | |
218 | window_change_handler(int sig) | |
219 | { | |
220 | received_window_change_signal = 1; | |
221 | signal(SIGWINCH, window_change_handler); | |
222 | } | |
223 | ||
224 | /* | |
225 | * Signal handler for signals that cause the program to terminate. These | |
226 | * signals must be trapped to restore terminal modes. | |
227 | */ | |
228 | /*ARGSUSED */ | |
229 | static void | |
230 | signal_handler(int sig) | |
231 | { | |
232 | received_signal = sig; | |
233 | quit_pending = 1; | |
234 | } | |
235 | ||
236 | /* | |
237 | * Returns current time in seconds from Jan 1, 1970 with the maximum | |
238 | * available resolution. | |
239 | */ | |
240 | ||
241 | static double | |
242 | get_current_time(void) | |
243 | { | |
244 | struct timeval tv; | |
245 | gettimeofday(&tv, NULL); | |
246 | return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0; | |
247 | } | |
248 | ||
249 | #define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1" | |
250 | void | |
251 | client_x11_get_proto(const char *display, const char *xauth_path, | |
252 | u_int trusted, char **_proto, char **_data) | |
253 | { | |
254 | char cmd[1024]; | |
255 | char line[512]; | |
256 | char xdisplay[512]; | |
257 | static char proto[512], data[512]; | |
258 | FILE *f; | |
259 | int got_data = 0, generated = 0, do_unlink = 0, i; | |
260 | char *xauthdir, *xauthfile; | |
261 | struct stat st; | |
262 | ||
263 | xauthdir = xauthfile = NULL; | |
264 | *_proto = proto; | |
265 | *_data = data; | |
266 | proto[0] = data[0] = '\0'; | |
267 | ||
268 | if (xauth_path == NULL ||(stat(xauth_path, &st) == -1)) { | |
269 | debug("No xauth program."); | |
270 | } else { | |
271 | if (display == NULL) { | |
272 | debug("x11_get_proto: DISPLAY not set"); | |
273 | return; | |
274 | } | |
275 | /* | |
276 | * Handle FamilyLocal case where $DISPLAY does | |
277 | * not match an authorization entry. For this we | |
278 | * just try "xauth list unix:displaynum.screennum". | |
279 | * XXX: "localhost" match to determine FamilyLocal | |
280 | * is not perfect. | |
281 | */ | |
282 | if (strncmp(display, "localhost:", 10) == 0) { | |
283 | snprintf(xdisplay, sizeof(xdisplay), "unix:%s", | |
284 | display + 10); | |
285 | display = xdisplay; | |
286 | } | |
287 | if (trusted == 0) { | |
288 | xauthdir = xmalloc(MAXPATHLEN); | |
289 | xauthfile = xmalloc(MAXPATHLEN); | |
290 | strlcpy(xauthdir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN); | |
291 | if (mkdtemp(xauthdir) != NULL) { | |
292 | do_unlink = 1; | |
293 | snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile", | |
294 | xauthdir); | |
295 | snprintf(cmd, sizeof(cmd), | |
296 | "%s -f %s generate %s " SSH_X11_PROTO | |
297 | " untrusted timeout 1200 2>" _PATH_DEVNULL, | |
298 | xauth_path, xauthfile, display); | |
299 | debug2("x11_get_proto: %s", cmd); | |
300 | if (system(cmd) == 0) | |
301 | generated = 1; | |
302 | } | |
303 | } | |
304 | ||
305 | /* | |
306 | * When in untrusted mode, we read the cookie only if it was | |
307 | * successfully generated as an untrusted one in the step | |
308 | * above. | |
309 | */ | |
310 | if (trusted || generated) { | |
311 | snprintf(cmd, sizeof(cmd), | |
312 | "%s %s%s list %s 2>" _PATH_DEVNULL, | |
313 | xauth_path, | |
314 | generated ? "-f " : "" , | |
315 | generated ? xauthfile : "", | |
316 | display); | |
317 | debug2("x11_get_proto: %s", cmd); | |
318 | f = popen(cmd, "r"); | |
319 | if (f && fgets(line, sizeof(line), f) && | |
320 | sscanf(line, "%*s %511s %511s", proto, data) == 2) | |
321 | got_data = 1; | |
322 | if (f) | |
323 | pclose(f); | |
324 | } else | |
325 | error("Warning: untrusted X11 forwarding setup failed: " | |
326 | "xauth key data not generated"); | |
327 | } | |
328 | ||
329 | if (do_unlink) { | |
330 | unlink(xauthfile); | |
331 | rmdir(xauthdir); | |
332 | } | |
333 | if (xauthdir) | |
334 | xfree(xauthdir); | |
335 | if (xauthfile) | |
336 | xfree(xauthfile); | |
337 | ||
338 | /* | |
339 | * If we didn't get authentication data, just make up some | |
340 | * data. The forwarding code will check the validity of the | |
341 | * response anyway, and substitute this data. The X11 | |
342 | * server, however, will ignore this fake data and use | |
343 | * whatever authentication mechanisms it was using otherwise | |
344 | * for the local connection. | |
345 | */ | |
346 | if (!got_data) { | |
347 | u_int32_t rnd = 0; | |
348 | ||
349 | logit("Warning: No xauth data; " | |
350 | "using fake authentication data for X11 forwarding."); | |
351 | strlcpy(proto, SSH_X11_PROTO, sizeof proto); | |
352 | for (i = 0; i < 16; i++) { | |
353 | if (i % 4 == 0) | |
354 | rnd = arc4random(); | |
355 | snprintf(data + 2 * i, sizeof data - 2 * i, "%02x", | |
356 | rnd & 0xff); | |
357 | rnd >>= 8; | |
358 | } | |
359 | } | |
360 | } | |
361 | ||
362 | /* | |
363 | * This is called when the interactive is entered. This checks if there is | |
364 | * an EOF coming on stdin. We must check this explicitly, as select() does | |
365 | * not appear to wake up when redirecting from /dev/null. | |
366 | */ | |
367 | ||
368 | static void | |
369 | client_check_initial_eof_on_stdin(void) | |
370 | { | |
371 | int len; | |
372 | char buf[1]; | |
373 | ||
374 | /* | |
375 | * If standard input is to be "redirected from /dev/null", we simply | |
376 | * mark that we have seen an EOF and send an EOF message to the | |
377 | * server. Otherwise, we try to read a single character; it appears | |
378 | * that for some files, such /dev/null, select() never wakes up for | |
379 | * read for this descriptor, which means that we never get EOF. This | |
380 | * way we will get the EOF if stdin comes from /dev/null or similar. | |
381 | */ | |
382 | if (stdin_null_flag) { | |
383 | /* Fake EOF on stdin. */ | |
384 | debug("Sending eof."); | |
385 | stdin_eof = 1; | |
386 | packet_start(SSH_CMSG_EOF); | |
387 | packet_send(); | |
388 | } else { | |
389 | enter_non_blocking(); | |
390 | ||
391 | /* Check for immediate EOF on stdin. */ | |
392 | len = read(fileno(stdin), buf, 1); | |
393 | if (len == 0) { | |
394 | /* | |
395 | * EOF. Record that we have seen it and send | |
396 | * EOF to server. | |
397 | */ | |
398 | debug("Sending eof."); | |
399 | stdin_eof = 1; | |
400 | packet_start(SSH_CMSG_EOF); | |
401 | packet_send(); | |
402 | } else if (len > 0) { | |
403 | /* | |
404 | * Got data. We must store the data in the buffer, | |
405 | * and also process it as an escape character if | |
406 | * appropriate. | |
407 | */ | |
408 | if ((u_char) buf[0] == escape_char1) | |
409 | escape_pending1 = 1; | |
410 | else | |
411 | buffer_append(&stdin_buffer, buf, 1); | |
412 | } | |
413 | leave_non_blocking(); | |
414 | } | |
415 | } | |
416 | ||
417 | ||
418 | /* | |
419 | * Make packets from buffered stdin data, and buffer them for sending to the | |
420 | * connection. | |
421 | */ | |
422 | ||
423 | static void | |
424 | client_make_packets_from_stdin_data(void) | |
425 | { | |
426 | u_int len; | |
427 | ||
428 | /* Send buffered stdin data to the server. */ | |
429 | while (buffer_len(&stdin_buffer) > 0 && | |
430 | packet_not_very_much_data_to_write()) { | |
431 | len = buffer_len(&stdin_buffer); | |
432 | /* Keep the packets at reasonable size. */ | |
433 | if (len > packet_get_maxsize()) | |
434 | len = packet_get_maxsize(); | |
435 | packet_start(SSH_CMSG_STDIN_DATA); | |
436 | packet_put_string(buffer_ptr(&stdin_buffer), len); | |
437 | packet_send(); | |
438 | buffer_consume(&stdin_buffer, len); | |
439 | /* If we have a pending EOF, send it now. */ | |
440 | if (stdin_eof && buffer_len(&stdin_buffer) == 0) { | |
441 | packet_start(SSH_CMSG_EOF); | |
442 | packet_send(); | |
443 | } | |
444 | } | |
445 | } | |
446 | ||
447 | /* | |
448 | * Checks if the client window has changed, and sends a packet about it to | |
449 | * the server if so. The actual change is detected elsewhere (by a software | |
450 | * interrupt on Unix); this just checks the flag and sends a message if | |
451 | * appropriate. | |
452 | */ | |
453 | ||
454 | static void | |
455 | client_check_window_change(void) | |
456 | { | |
457 | struct winsize ws; | |
458 | ||
459 | if (! received_window_change_signal) | |
460 | return; | |
461 | /** XXX race */ | |
462 | received_window_change_signal = 0; | |
463 | ||
464 | debug2("client_check_window_change: changed"); | |
465 | ||
466 | if (compat20) { | |
467 | channel_send_window_changes(); | |
468 | } else { | |
469 | if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0) | |
470 | return; | |
471 | packet_start(SSH_CMSG_WINDOW_SIZE); | |
472 | packet_put_int((u_int)ws.ws_row); | |
473 | packet_put_int((u_int)ws.ws_col); | |
474 | packet_put_int((u_int)ws.ws_xpixel); | |
475 | packet_put_int((u_int)ws.ws_ypixel); | |
476 | packet_send(); | |
477 | } | |
478 | } | |
479 | ||
480 | static void | |
481 | client_global_request_reply(int type, u_int32_t seq, void *ctxt) | |
482 | { | |
483 | struct global_confirm *gc; | |
484 | ||
485 | if ((gc = TAILQ_FIRST(&global_confirms)) == NULL) | |
486 | return; | |
487 | if (gc->cb != NULL) | |
488 | gc->cb(type, seq, gc->ctx); | |
489 | if (--gc->ref_count <= 0) { | |
490 | TAILQ_REMOVE(&global_confirms, gc, entry); | |
491 | bzero(gc, sizeof(*gc)); | |
492 | xfree(gc); | |
493 | } | |
494 | ||
495 | packet_set_alive_timeouts(0); | |
496 | } | |
497 | ||
498 | static void | |
499 | server_alive_check(void) | |
500 | { | |
501 | if (packet_inc_alive_timeouts() > options.server_alive_count_max) { | |
502 | logit("Timeout, server not responding."); | |
503 | cleanup_exit(255); | |
504 | } | |
505 | packet_start(SSH2_MSG_GLOBAL_REQUEST); | |
506 | packet_put_cstring("keepalive@openssh.com"); | |
507 | packet_put_char(1); /* boolean: want reply */ | |
508 | packet_send(); | |
509 | /* Insert an empty placeholder to maintain ordering */ | |
510 | client_register_global_confirm(NULL, NULL); | |
511 | } | |
512 | ||
513 | /* | |
514 | * Waits until the client can do something (some data becomes available on | |
515 | * one of the file descriptors). | |
516 | */ | |
517 | static void | |
518 | client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp, | |
519 | int *maxfdp, u_int *nallocp, int rekeying) | |
520 | { | |
521 | struct timeval tv, *tvp; | |
522 | int ret; | |
523 | ||
524 | /* Add any selections by the channel mechanism. */ | |
525 | channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, rekeying); | |
526 | ||
527 | if (!compat20) { | |
528 | /* Read from the connection, unless our buffers are full. */ | |
529 | if (buffer_len(&stdout_buffer) < buffer_high && | |
530 | buffer_len(&stderr_buffer) < buffer_high && | |
531 | channel_not_very_much_buffered_data()) | |
532 | FD_SET(connection_in, *readsetp); | |
533 | /* | |
534 | * Read from stdin, unless we have seen EOF or have very much | |
535 | * buffered data to send to the server. | |
536 | */ | |
537 | if (!stdin_eof && packet_not_very_much_data_to_write()) | |
538 | FD_SET(fileno(stdin), *readsetp); | |
539 | ||
540 | /* Select stdout/stderr if have data in buffer. */ | |
541 | if (buffer_len(&stdout_buffer) > 0) | |
542 | FD_SET(fileno(stdout), *writesetp); | |
543 | if (buffer_len(&stderr_buffer) > 0) | |
544 | FD_SET(fileno(stderr), *writesetp); | |
545 | } else { | |
546 | /* channel_prepare_select could have closed the last channel */ | |
547 | if (session_closed && !channel_still_open() && | |
548 | !packet_have_data_to_write()) { | |
549 | /* clear mask since we did not call select() */ | |
550 | memset(*readsetp, 0, *nallocp); | |
551 | memset(*writesetp, 0, *nallocp); | |
552 | return; | |
553 | } else { | |
554 | FD_SET(connection_in, *readsetp); | |
555 | } | |
556 | } | |
557 | ||
558 | /* Select server connection if have data to write to the server. */ | |
559 | if (packet_have_data_to_write()) | |
560 | FD_SET(connection_out, *writesetp); | |
561 | ||
562 | if (muxserver_sock != -1) | |
563 | FD_SET(muxserver_sock, *readsetp); | |
564 | ||
565 | /* | |
566 | * Wait for something to happen. This will suspend the process until | |
567 | * some selected descriptor can be read, written, or has some other | |
568 | * event pending. | |
569 | */ | |
570 | ||
571 | if (options.server_alive_interval == 0 || !compat20) | |
572 | tvp = NULL; | |
573 | else { | |
574 | tv.tv_sec = options.server_alive_interval; | |
575 | tv.tv_usec = 0; | |
576 | tvp = &tv; | |
577 | } | |
578 | ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp); | |
579 | if (ret < 0) { | |
580 | char buf[100]; | |
581 | ||
582 | /* | |
583 | * We have to clear the select masks, because we return. | |
584 | * We have to return, because the mainloop checks for the flags | |
585 | * set by the signal handlers. | |
586 | */ | |
587 | memset(*readsetp, 0, *nallocp); | |
588 | memset(*writesetp, 0, *nallocp); | |
589 | ||
590 | if (errno == EINTR) | |
591 | return; | |
592 | /* Note: we might still have data in the buffers. */ | |
593 | snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno)); | |
594 | buffer_append(&stderr_buffer, buf, strlen(buf)); | |
595 | quit_pending = 1; | |
596 | } else if (ret == 0) | |
597 | server_alive_check(); | |
598 | } | |
599 | ||
600 | static void | |
601 | client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr) | |
602 | { | |
603 | /* Flush stdout and stderr buffers. */ | |
604 | if (buffer_len(bout) > 0) | |
605 | atomicio(vwrite, fileno(stdout), buffer_ptr(bout), | |
606 | buffer_len(bout)); | |
607 | if (buffer_len(berr) > 0) | |
608 | atomicio(vwrite, fileno(stderr), buffer_ptr(berr), | |
609 | buffer_len(berr)); | |
610 | ||
611 | leave_raw_mode(); | |
612 | ||
613 | /* | |
614 | * Free (and clear) the buffer to reduce the amount of data that gets | |
615 | * written to swap. | |
616 | */ | |
617 | buffer_free(bin); | |
618 | buffer_free(bout); | |
619 | buffer_free(berr); | |
620 | ||
621 | /* Send the suspend signal to the program itself. */ | |
622 | kill(getpid(), SIGTSTP); | |
623 | ||
624 | /* Reset window sizes in case they have changed */ | |
625 | received_window_change_signal = 1; | |
626 | ||
627 | /* OK, we have been continued by the user. Reinitialize buffers. */ | |
628 | buffer_init(bin); | |
629 | buffer_init(bout); | |
630 | buffer_init(berr); | |
631 | ||
632 | enter_raw_mode(); | |
633 | } | |
634 | ||
635 | static void | |
636 | client_process_net_input(fd_set *readset) | |
637 | { | |
638 | int len, cont = 0; | |
639 | char buf[SSH_IOBUFSZ]; | |
640 | ||
641 | /* | |
642 | * Read input from the server, and add any such data to the buffer of | |
643 | * the packet subsystem. | |
644 | */ | |
645 | if (FD_ISSET(connection_in, readset)) { | |
646 | /* Read as much as possible. */ | |
647 | len = roaming_read(connection_in, buf, sizeof(buf), &cont); | |
648 | if (len == 0 && cont == 0) { | |
649 | /* | |
650 | * Received EOF. The remote host has closed the | |
651 | * connection. | |
652 | */ | |
653 | snprintf(buf, sizeof buf, | |
654 | "Connection to %.300s closed by remote host.\r\n", | |
655 | host); | |
656 | buffer_append(&stderr_buffer, buf, strlen(buf)); | |
657 | quit_pending = 1; | |
658 | return; | |
659 | } | |
660 | /* | |
661 | * There is a kernel bug on Solaris that causes select to | |
662 | * sometimes wake up even though there is no data available. | |
663 | */ | |
664 | if (len < 0 && | |
665 | (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK)) | |
666 | len = 0; | |
667 | ||
668 | if (len < 0) { | |
669 | /* | |
670 | * An error has encountered. Perhaps there is a | |
671 | * network problem. | |
672 | */ | |
673 | snprintf(buf, sizeof buf, | |
674 | "Read from remote host %.300s: %.100s\r\n", | |
675 | host, strerror(errno)); | |
676 | buffer_append(&stderr_buffer, buf, strlen(buf)); | |
677 | quit_pending = 1; | |
678 | return; | |
679 | } | |
680 | packet_process_incoming(buf, len); | |
681 | } | |
682 | } | |
683 | ||
684 | static void | |
685 | client_status_confirm(int type, Channel *c, void *ctx) | |
686 | { | |
687 | struct channel_reply_ctx *cr = (struct channel_reply_ctx *)ctx; | |
688 | char errmsg[256]; | |
689 | int tochan; | |
690 | ||
691 | /* XXX supress on mux _client_ quietmode */ | |
692 | tochan = options.log_level >= SYSLOG_LEVEL_ERROR && | |
693 | c->ctl_fd != -1 && c->extended_usage == CHAN_EXTENDED_WRITE; | |
694 | ||
695 | if (type == SSH2_MSG_CHANNEL_SUCCESS) { | |
696 | debug2("%s request accepted on channel %d", | |
697 | cr->request_type, c->self); | |
698 | } else if (type == SSH2_MSG_CHANNEL_FAILURE) { | |
699 | if (tochan) { | |
700 | snprintf(errmsg, sizeof(errmsg), | |
701 | "%s request failed\r\n", cr->request_type); | |
702 | } else { | |
703 | snprintf(errmsg, sizeof(errmsg), | |
704 | "%s request failed on channel %d", | |
705 | cr->request_type, c->self); | |
706 | } | |
707 | /* If error occurred on primary session channel, then exit */ | |
708 | if (cr->do_close && c->self == session_ident) | |
709 | fatal("%s", errmsg); | |
710 | /* If error occurred on mux client, append to their stderr */ | |
711 | if (tochan) | |
712 | buffer_append(&c->extended, errmsg, strlen(errmsg)); | |
713 | else | |
714 | error("%s", errmsg); | |
715 | if (cr->do_close) { | |
716 | chan_read_failed(c); | |
717 | chan_write_failed(c); | |
718 | } | |
719 | } | |
720 | xfree(cr); | |
721 | } | |
722 | ||
723 | static void | |
724 | client_abandon_status_confirm(Channel *c, void *ctx) | |
725 | { | |
726 | xfree(ctx); | |
727 | } | |
728 | ||
729 | static void | |
730 | client_expect_confirm(int id, const char *request, int do_close) | |
731 | { | |
732 | struct channel_reply_ctx *cr = xmalloc(sizeof(*cr)); | |
733 | ||
734 | cr->request_type = request; | |
735 | cr->do_close = do_close; | |
736 | ||
737 | channel_register_status_confirm(id, client_status_confirm, | |
738 | client_abandon_status_confirm, cr); | |
739 | } | |
740 | ||
741 | void | |
742 | client_register_global_confirm(global_confirm_cb *cb, void *ctx) | |
743 | { | |
744 | struct global_confirm *gc, *last_gc; | |
745 | ||
746 | /* Coalesce identical callbacks */ | |
747 | last_gc = TAILQ_LAST(&global_confirms, global_confirms); | |
748 | if (last_gc && last_gc->cb == cb && last_gc->ctx == ctx) { | |
749 | if (++last_gc->ref_count >= INT_MAX) | |
750 | fatal("%s: last_gc->ref_count = %d", | |
751 | __func__, last_gc->ref_count); | |
752 | return; | |
753 | } | |
754 | ||
755 | gc = xmalloc(sizeof(*gc)); | |
756 | gc->cb = cb; | |
757 | gc->ctx = ctx; | |
758 | gc->ref_count = 1; | |
759 | TAILQ_INSERT_TAIL(&global_confirms, gc, entry); | |
760 | } | |
761 | ||
762 | static void | |
763 | process_cmdline(void) | |
764 | { | |
765 | void (*handler)(int); | |
766 | char *s, *cmd, *cancel_host; | |
767 | int delete = 0; | |
768 | int local = 0, remote = 0, dynamic = 0; | |
769 | int cancel_port; | |
770 | Forward fwd; | |
771 | ||
772 | bzero(&fwd, sizeof(fwd)); | |
773 | fwd.listen_host = fwd.connect_host = NULL; | |
774 | ||
775 | leave_raw_mode(); | |
776 | handler = signal(SIGINT, SIG_IGN); | |
777 | cmd = s = read_passphrase("\r\nssh> ", RP_ECHO); | |
778 | if (s == NULL) | |
779 | goto out; | |
780 | while (isspace(*s)) | |
781 | s++; | |
782 | if (*s == '-') | |
783 | s++; /* Skip cmdline '-', if any */ | |
784 | if (*s == '\0') | |
785 | goto out; | |
786 | ||
787 | if (*s == 'h' || *s == 'H' || *s == '?') { | |
788 | logit("Commands:"); | |
789 | logit(" -L[bind_address:]port:host:hostport " | |
790 | "Request local forward"); | |
791 | logit(" -R[bind_address:]port:host:hostport " | |
792 | "Request remote forward"); | |
793 | logit(" -D[bind_address:]port " | |
794 | "Request dynamic forward"); | |
795 | logit(" -KR[bind_address:]port " | |
796 | "Cancel remote forward"); | |
797 | if (!options.permit_local_command) | |
798 | goto out; | |
799 | logit(" !args " | |
800 | "Execute local command"); | |
801 | goto out; | |
802 | } | |
803 | ||
804 | if (*s == '!' && options.permit_local_command) { | |
805 | s++; | |
806 | ssh_local_cmd(s); | |
807 | goto out; | |
808 | } | |
809 | ||
810 | if (*s == 'K') { | |
811 | delete = 1; | |
812 | s++; | |
813 | } | |
814 | if (*s == 'L') | |
815 | local = 1; | |
816 | else if (*s == 'R') | |
817 | remote = 1; | |
818 | else if (*s == 'D') | |
819 | dynamic = 1; | |
820 | else { | |
821 | logit("Invalid command."); | |
822 | goto out; | |
823 | } | |
824 | ||
825 | if ((local || dynamic) && delete) { | |
826 | logit("Not supported."); | |
827 | goto out; | |
828 | } | |
829 | if (remote && delete && !compat20) { | |
830 | logit("Not supported for SSH protocol version 1."); | |
831 | goto out; | |
832 | } | |
833 | ||
834 | while (isspace(*++s)) | |
835 | ; | |
836 | ||
837 | if (delete) { | |
838 | cancel_port = 0; | |
839 | cancel_host = hpdelim(&s); /* may be NULL */ | |
840 | if (s != NULL) { | |
841 | cancel_port = a2port(s); | |
842 | cancel_host = cleanhostname(cancel_host); | |
843 | } else { | |
844 | cancel_port = a2port(cancel_host); | |
845 | cancel_host = NULL; | |
846 | } | |
847 | if (cancel_port <= 0) { | |
848 | logit("Bad forwarding close port"); | |
849 | goto out; | |
850 | } | |
851 | channel_request_rforward_cancel(cancel_host, cancel_port); | |
852 | } else { | |
853 | if (!parse_forward(&fwd, s, dynamic, remote)) { | |
854 | logit("Bad forwarding specification."); | |
855 | goto out; | |
856 | } | |
857 | if (local || dynamic) { | |
858 | if (channel_setup_local_fwd_listener(fwd.listen_host, | |
859 | fwd.listen_port, fwd.connect_host, | |
860 | fwd.connect_port, options.gateway_ports) < 0) { | |
861 | logit("Port forwarding failed."); | |
862 | goto out; | |
863 | } | |
864 | } else { | |
865 | if (channel_request_remote_forwarding(fwd.listen_host, | |
866 | fwd.listen_port, fwd.connect_host, | |
867 | fwd.connect_port) < 0) { | |
868 | logit("Port forwarding failed."); | |
869 | goto out; | |
870 | } | |
871 | } | |
872 | ||
873 | logit("Forwarding port."); | |
874 | } | |
875 | ||
876 | out: | |
877 | signal(SIGINT, handler); | |
878 | enter_raw_mode(); | |
879 | if (cmd) | |
880 | xfree(cmd); | |
881 | if (fwd.listen_host != NULL) | |
882 | xfree(fwd.listen_host); | |
883 | if (fwd.connect_host != NULL) | |
884 | xfree(fwd.connect_host); | |
885 | } | |
886 | ||
887 | /* | |
888 | * Process the characters one by one, call with c==NULL for proto1 case. | |
889 | */ | |
890 | static int | |
891 | process_escapes(Channel *c, Buffer *bin, Buffer *bout, Buffer *berr, | |
892 | char *buf, int len) | |
893 | { | |
894 | char string[1024]; | |
895 | pid_t pid; | |
896 | int bytes = 0; | |
897 | u_int i; | |
898 | u_char ch; | |
899 | char *s; | |
900 | int *escape_pendingp, escape_char; | |
901 | struct escape_filter_ctx *efc; | |
902 | ||
903 | if (c == NULL) { | |
904 | escape_pendingp = &escape_pending1; | |
905 | escape_char = escape_char1; | |
906 | } else { | |
907 | if (c->filter_ctx == NULL) | |
908 | return 0; | |
909 | efc = (struct escape_filter_ctx *)c->filter_ctx; | |
910 | escape_pendingp = &efc->escape_pending; | |
911 | escape_char = efc->escape_char; | |
912 | } | |
913 | ||
914 | if (len <= 0) | |
915 | return (0); | |
916 | ||
917 | for (i = 0; i < (u_int)len; i++) { | |
918 | /* Get one character at a time. */ | |
919 | ch = buf[i]; | |
920 | ||
921 | if (*escape_pendingp) { | |
922 | /* We have previously seen an escape character. */ | |
923 | /* Clear the flag now. */ | |
924 | *escape_pendingp = 0; | |
925 | ||
926 | /* Process the escaped character. */ | |
927 | switch (ch) { | |
928 | case '.': | |
929 | /* Terminate the connection. */ | |
930 | snprintf(string, sizeof string, "%c.\r\n", | |
931 | escape_char); | |
932 | buffer_append(berr, string, strlen(string)); | |
933 | ||
934 | if (c && c->ctl_fd != -1) { | |
935 | chan_read_failed(c); | |
936 | chan_write_failed(c); | |
937 | return 0; | |
938 | } else | |
939 | quit_pending = 1; | |
940 | return -1; | |
941 | ||
942 | case 'Z' - 64: | |
943 | /* XXX support this for mux clients */ | |
944 | if (c && c->ctl_fd != -1) { | |
945 | noescape: | |
946 | snprintf(string, sizeof string, | |
947 | "%c%c escape not available to " | |
948 | "multiplexed sessions\r\n", | |
949 | escape_char, ch); | |
950 | buffer_append(berr, string, | |
951 | strlen(string)); | |
952 | continue; | |
953 | } | |
954 | /* Suspend the program. Inform the user */ | |
955 | snprintf(string, sizeof string, | |
956 | "%c^Z [suspend ssh]\r\n", escape_char); | |
957 | buffer_append(berr, string, strlen(string)); | |
958 | ||
959 | /* Restore terminal modes and suspend. */ | |
960 | client_suspend_self(bin, bout, berr); | |
961 | ||
962 | /* We have been continued. */ | |
963 | continue; | |
964 | ||
965 | case 'B': | |
966 | if (compat20) { | |
967 | snprintf(string, sizeof string, | |
968 | "%cB\r\n", escape_char); | |
969 | buffer_append(berr, string, | |
970 | strlen(string)); | |
971 | channel_request_start(session_ident, | |
972 | "break", 0); | |
973 | packet_put_int(1000); | |
974 | packet_send(); | |
975 | } | |
976 | continue; | |
977 | ||
978 | case 'R': | |
979 | if (compat20) { | |
980 | if (datafellows & SSH_BUG_NOREKEY) | |
981 | logit("Server does not " | |
982 | "support re-keying"); | |
983 | else | |
984 | need_rekeying = 1; | |
985 | } | |
986 | continue; | |
987 | ||
988 | case '&': | |
989 | if (c && c->ctl_fd != -1) | |
990 | goto noescape; | |
991 | /* | |
992 | * Detach the program (continue to serve | |
993 | * connections, but put in background and no | |
994 | * more new connections). | |
995 | */ | |
996 | /* Restore tty modes. */ | |
997 | leave_raw_mode(); | |
998 | ||
999 | /* Stop listening for new connections. */ | |
1000 | channel_stop_listening(); | |
1001 | ||
1002 | snprintf(string, sizeof string, | |
1003 | "%c& [backgrounded]\n", escape_char); | |
1004 | buffer_append(berr, string, strlen(string)); | |
1005 | ||
1006 | /* Fork into background. */ | |
1007 | pid = fork(); | |
1008 | if (pid < 0) { | |
1009 | error("fork: %.100s", strerror(errno)); | |
1010 | continue; | |
1011 | } | |
1012 | if (pid != 0) { /* This is the parent. */ | |
1013 | /* The parent just exits. */ | |
1014 | exit(0); | |
1015 | } | |
1016 | /* The child continues serving connections. */ | |
1017 | if (compat20) { | |
1018 | buffer_append(bin, "\004", 1); | |
1019 | /* fake EOF on stdin */ | |
1020 | return -1; | |
1021 | } else if (!stdin_eof) { | |
1022 | /* | |
1023 | * Sending SSH_CMSG_EOF alone does not | |
1024 | * always appear to be enough. So we | |
1025 | * try to send an EOF character first. | |
1026 | */ | |
1027 | packet_start(SSH_CMSG_STDIN_DATA); | |
1028 | packet_put_string("\004", 1); | |
1029 | packet_send(); | |
1030 | /* Close stdin. */ | |
1031 | stdin_eof = 1; | |
1032 | if (buffer_len(bin) == 0) { | |
1033 | packet_start(SSH_CMSG_EOF); | |
1034 | packet_send(); | |
1035 | } | |
1036 | } | |
1037 | continue; | |
1038 | ||
1039 | case '?': | |
1040 | if (c && c->ctl_fd != -1) { | |
1041 | snprintf(string, sizeof string, | |
1042 | "%c?\r\n\ | |
1043 | Supported escape sequences:\r\n\ | |
1044 | %c. - terminate session\r\n\ | |
1045 | %cB - send a BREAK to the remote system\r\n\ | |
1046 | %cR - Request rekey (SSH protocol 2 only)\r\n\ | |
1047 | %c# - list forwarded connections\r\n\ | |
1048 | %c? - this message\r\n\ | |
1049 | %c%c - send the escape character by typing it twice\r\n\ | |
1050 | (Note that escapes are only recognized immediately after newline.)\r\n", | |
1051 | escape_char, escape_char, | |
1052 | escape_char, escape_char, | |
1053 | escape_char, escape_char, | |
1054 | escape_char, escape_char); | |
1055 | } else { | |
1056 | snprintf(string, sizeof string, | |
1057 | "%c?\r\n\ | |
1058 | Supported escape sequences:\r\n\ | |
1059 | %c. - terminate connection (and any multiplexed sessions)\r\n\ | |
1060 | %cB - send a BREAK to the remote system\r\n\ | |
1061 | %cC - open a command line\r\n\ | |
1062 | %cR - Request rekey (SSH protocol 2 only)\r\n\ | |
1063 | %c^Z - suspend ssh\r\n\ | |
1064 | %c# - list forwarded connections\r\n\ | |
1065 | %c& - background ssh (when waiting for connections to terminate)\r\n\ | |
1066 | %c? - this message\r\n\ | |
1067 | %c%c - send the escape character by typing it twice\r\n\ | |
1068 | (Note that escapes are only recognized immediately after newline.)\r\n", | |
1069 | escape_char, escape_char, | |
1070 | escape_char, escape_char, | |
1071 | escape_char, escape_char, | |
1072 | escape_char, escape_char, | |
1073 | escape_char, escape_char, | |
1074 | escape_char); | |
1075 | } | |
1076 | buffer_append(berr, string, strlen(string)); | |
1077 | continue; | |
1078 | ||
1079 | case '#': | |
1080 | snprintf(string, sizeof string, "%c#\r\n", | |
1081 | escape_char); | |
1082 | buffer_append(berr, string, strlen(string)); | |
1083 | s = channel_open_message(); | |
1084 | buffer_append(berr, s, strlen(s)); | |
1085 | xfree(s); | |
1086 | continue; | |
1087 | ||
1088 | case 'C': | |
1089 | if (c && c->ctl_fd != -1) | |
1090 | goto noescape; | |
1091 | process_cmdline(); | |
1092 | continue; | |
1093 | ||
1094 | default: | |
1095 | if (ch != escape_char) { | |
1096 | buffer_put_char(bin, escape_char); | |
1097 | bytes++; | |
1098 | } | |
1099 | /* Escaped characters fall through here */ | |
1100 | break; | |
1101 | } | |
1102 | } else { | |
1103 | /* | |
1104 | * The previous character was not an escape char. | |
1105 | * Check if this is an escape. | |
1106 | */ | |
1107 | if (last_was_cr && ch == escape_char) { | |
1108 | /* | |
1109 | * It is. Set the flag and continue to | |
1110 | * next character. | |
1111 | */ | |
1112 | *escape_pendingp = 1; | |
1113 | continue; | |
1114 | } | |
1115 | } | |
1116 | ||
1117 | /* | |
1118 | * Normal character. Record whether it was a newline, | |
1119 | * and append it to the buffer. | |
1120 | */ | |
1121 | last_was_cr = (ch == '\r' || ch == '\n'); | |
1122 | buffer_put_char(bin, ch); | |
1123 | bytes++; | |
1124 | } | |
1125 | return bytes; | |
1126 | } | |
1127 | ||
1128 | static void | |
1129 | client_process_input(fd_set *readset) | |
1130 | { | |
1131 | int len; | |
1132 | char buf[SSH_IOBUFSZ]; | |
1133 | ||
1134 | /* Read input from stdin. */ | |
1135 | if (FD_ISSET(fileno(stdin), readset)) { | |
1136 | /* Read as much as possible. */ | |
1137 | len = read(fileno(stdin), buf, sizeof(buf)); | |
1138 | if (len < 0 && | |
1139 | (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK)) | |
1140 | return; /* we'll try again later */ | |
1141 | if (len <= 0) { | |
1142 | /* | |
1143 | * Received EOF or error. They are treated | |
1144 | * similarly, except that an error message is printed | |
1145 | * if it was an error condition. | |
1146 | */ | |
1147 | if (len < 0) { | |
1148 | snprintf(buf, sizeof buf, "read: %.100s\r\n", | |
1149 | strerror(errno)); | |
1150 | buffer_append(&stderr_buffer, buf, strlen(buf)); | |
1151 | } | |
1152 | /* Mark that we have seen EOF. */ | |
1153 | stdin_eof = 1; | |
1154 | /* | |
1155 | * Send an EOF message to the server unless there is | |
1156 | * data in the buffer. If there is data in the | |
1157 | * buffer, no message will be sent now. Code | |
1158 | * elsewhere will send the EOF when the buffer | |
1159 | * becomes empty if stdin_eof is set. | |
1160 | */ | |
1161 | if (buffer_len(&stdin_buffer) == 0) { | |
1162 | packet_start(SSH_CMSG_EOF); | |
1163 | packet_send(); | |
1164 | } | |
1165 | } else if (escape_char1 == SSH_ESCAPECHAR_NONE) { | |
1166 | /* | |
1167 | * Normal successful read, and no escape character. | |
1168 | * Just append the data to buffer. | |
1169 | */ | |
1170 | buffer_append(&stdin_buffer, buf, len); | |
1171 | } else { | |
1172 | /* | |
1173 | * Normal, successful read. But we have an escape | |
1174 | * character and have to process the characters one | |
1175 | * by one. | |
1176 | */ | |
1177 | if (process_escapes(NULL, &stdin_buffer, | |
1178 | &stdout_buffer, &stderr_buffer, buf, len) == -1) | |
1179 | return; | |
1180 | } | |
1181 | } | |
1182 | } | |
1183 | ||
1184 | static void | |
1185 | client_process_output(fd_set *writeset) | |
1186 | { | |
1187 | int len; | |
1188 | char buf[100]; | |
1189 | ||
1190 | /* Write buffered output to stdout. */ | |
1191 | if (FD_ISSET(fileno(stdout), writeset)) { | |
1192 | /* Write as much data as possible. */ | |
1193 | len = write(fileno(stdout), buffer_ptr(&stdout_buffer), | |
1194 | buffer_len(&stdout_buffer)); | |
1195 | if (len <= 0) { | |
1196 | if (errno == EINTR || errno == EAGAIN || | |
1197 | errno == EWOULDBLOCK) | |
1198 | len = 0; | |
1199 | else { | |
1200 | /* | |
1201 | * An error or EOF was encountered. Put an | |
1202 | * error message to stderr buffer. | |
1203 | */ | |
1204 | snprintf(buf, sizeof buf, | |
1205 | "write stdout: %.50s\r\n", strerror(errno)); | |
1206 | buffer_append(&stderr_buffer, buf, strlen(buf)); | |
1207 | quit_pending = 1; | |
1208 | return; | |
1209 | } | |
1210 | } | |
1211 | /* Consume printed data from the buffer. */ | |
1212 | buffer_consume(&stdout_buffer, len); | |
1213 | } | |
1214 | /* Write buffered output to stderr. */ | |
1215 | if (FD_ISSET(fileno(stderr), writeset)) { | |
1216 | /* Write as much data as possible. */ | |
1217 | len = write(fileno(stderr), buffer_ptr(&stderr_buffer), | |
1218 | buffer_len(&stderr_buffer)); | |
1219 | if (len <= 0) { | |
1220 | if (errno == EINTR || errno == EAGAIN || | |
1221 | errno == EWOULDBLOCK) | |
1222 | len = 0; | |
1223 | else { | |
1224 | /* | |
1225 | * EOF or error, but can't even print | |
1226 | * error message. | |
1227 | */ | |
1228 | quit_pending = 1; | |
1229 | return; | |
1230 | } | |
1231 | } | |
1232 | /* Consume printed characters from the buffer. */ | |
1233 | buffer_consume(&stderr_buffer, len); | |
1234 | } | |
1235 | } | |
1236 | ||
1237 | /* | |
1238 | * Get packets from the connection input buffer, and process them as long as | |
1239 | * there are packets available. | |
1240 | * | |
1241 | * Any unknown packets received during the actual | |
1242 | * session cause the session to terminate. This is | |
1243 | * intended to make debugging easier since no | |
1244 | * confirmations are sent. Any compatible protocol | |
1245 | * extensions must be negotiated during the | |
1246 | * preparatory phase. | |
1247 | */ | |
1248 | ||
1249 | static void | |
1250 | client_process_buffered_input_packets(void) | |
1251 | { | |
1252 | dispatch_run(DISPATCH_NONBLOCK, &quit_pending, | |
1253 | compat20 ? xxx_kex : NULL); | |
1254 | } | |
1255 | ||
1256 | /* scan buf[] for '~' before sending data to the peer */ | |
1257 | ||
1258 | /* Helper: allocate a new escape_filter_ctx and fill in its escape char */ | |
1259 | void * | |
1260 | client_new_escape_filter_ctx(int escape_char) | |
1261 | { | |
1262 | struct escape_filter_ctx *ret; | |
1263 | ||
1264 | ret = xmalloc(sizeof(*ret)); | |
1265 | ret->escape_pending = 0; | |
1266 | ret->escape_char = escape_char; | |
1267 | return (void *)ret; | |
1268 | } | |
1269 | ||
1270 | /* Free the escape filter context on channel free */ | |
1271 | void | |
1272 | client_filter_cleanup(int cid, void *ctx) | |
1273 | { | |
1274 | xfree(ctx); | |
1275 | } | |
1276 | ||
1277 | int | |
1278 | client_simple_escape_filter(Channel *c, char *buf, int len) | |
1279 | { | |
1280 | if (c->extended_usage != CHAN_EXTENDED_WRITE) | |
1281 | return 0; | |
1282 | ||
1283 | return process_escapes(c, &c->input, &c->output, &c->extended, | |
1284 | buf, len); | |
1285 | } | |
1286 | ||
1287 | static void | |
1288 | client_channel_closed(int id, void *arg) | |
1289 | { | |
1290 | channel_cancel_cleanup(id); | |
1291 | session_closed = 1; | |
1292 | leave_raw_mode(); | |
1293 | } | |
1294 | ||
1295 | /* | |
1296 | * Implements the interactive session with the server. This is called after | |
1297 | * the user has been authenticated, and a command has been started on the | |
1298 | * remote host. If escape_char != SSH_ESCAPECHAR_NONE, it is the character | |
1299 | * used as an escape character for terminating or suspending the session. | |
1300 | */ | |
1301 | ||
1302 | int | |
1303 | client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id) | |
1304 | { | |
1305 | fd_set *readset = NULL, *writeset = NULL; | |
1306 | double start_time, total_time; | |
1307 | int max_fd = 0, max_fd2 = 0, len, rekeying = 0; | |
1308 | u_int64_t ibytes, obytes; | |
1309 | u_int nalloc = 0; | |
1310 | char buf[100]; | |
1311 | ||
1312 | debug("Entering interactive session."); | |
1313 | ||
1314 | start_time = get_current_time(); | |
1315 | ||
1316 | /* Initialize variables. */ | |
1317 | escape_pending1 = 0; | |
1318 | last_was_cr = 1; | |
1319 | exit_status = -1; | |
1320 | stdin_eof = 0; | |
1321 | buffer_high = 64 * 1024; | |
1322 | connection_in = packet_get_connection_in(); | |
1323 | connection_out = packet_get_connection_out(); | |
1324 | max_fd = MAX(connection_in, connection_out); | |
1325 | if (muxserver_sock != -1) | |
1326 | max_fd = MAX(max_fd, muxserver_sock); | |
1327 | ||
1328 | if (!compat20) { | |
1329 | /* enable nonblocking unless tty */ | |
1330 | if (!isatty(fileno(stdin))) | |
1331 | set_nonblock(fileno(stdin)); | |
1332 | if (!isatty(fileno(stdout))) | |
1333 | set_nonblock(fileno(stdout)); | |
1334 | if (!isatty(fileno(stderr))) | |
1335 | set_nonblock(fileno(stderr)); | |
1336 | max_fd = MAX(max_fd, fileno(stdin)); | |
1337 | max_fd = MAX(max_fd, fileno(stdout)); | |
1338 | max_fd = MAX(max_fd, fileno(stderr)); | |
1339 | } | |
1340 | quit_pending = 0; | |
1341 | escape_char1 = escape_char_arg; | |
1342 | ||
1343 | /* Initialize buffers. */ | |
1344 | buffer_init(&stdin_buffer); | |
1345 | buffer_init(&stdout_buffer); | |
1346 | buffer_init(&stderr_buffer); | |
1347 | ||
1348 | client_init_dispatch(); | |
1349 | ||
1350 | /* | |
1351 | * Set signal handlers, (e.g. to restore non-blocking mode) | |
1352 | * but don't overwrite SIG_IGN, matches behaviour from rsh(1) | |
1353 | */ | |
1354 | if (signal(SIGHUP, SIG_IGN) != SIG_IGN) | |
1355 | signal(SIGHUP, signal_handler); | |
1356 | if (signal(SIGINT, SIG_IGN) != SIG_IGN) | |
1357 | signal(SIGINT, signal_handler); | |
1358 | if (signal(SIGQUIT, SIG_IGN) != SIG_IGN) | |
1359 | signal(SIGQUIT, signal_handler); | |
1360 | if (signal(SIGTERM, SIG_IGN) != SIG_IGN) | |
1361 | signal(SIGTERM, signal_handler); | |
1362 | signal(SIGWINCH, window_change_handler); | |
1363 | ||
1364 | if (have_pty) | |
1365 | enter_raw_mode(); | |
1366 | ||
1367 | if (compat20) { | |
1368 | session_ident = ssh2_chan_id; | |
1369 | if (escape_char_arg != SSH_ESCAPECHAR_NONE) | |
1370 | channel_register_filter(session_ident, | |
1371 | client_simple_escape_filter, NULL, | |
1372 | client_filter_cleanup, | |
1373 | client_new_escape_filter_ctx(escape_char_arg)); | |
1374 | if (session_ident != -1) | |
1375 | channel_register_cleanup(session_ident, | |
1376 | client_channel_closed, 0); | |
1377 | } else { | |
1378 | /* Check if we should immediately send eof on stdin. */ | |
1379 | client_check_initial_eof_on_stdin(); | |
1380 | } | |
1381 | ||
1382 | /* Main loop of the client for the interactive session mode. */ | |
1383 | while (!quit_pending) { | |
1384 | ||
1385 | /* Process buffered packets sent by the server. */ | |
1386 | client_process_buffered_input_packets(); | |
1387 | ||
1388 | if (compat20 && session_closed && !channel_still_open()) | |
1389 | break; | |
1390 | ||
1391 | rekeying = (xxx_kex != NULL && !xxx_kex->done); | |
1392 | ||
1393 | if (rekeying) { | |
1394 | debug("rekeying in progress"); | |
1395 | } else { | |
1396 | /* | |
1397 | * Make packets of buffered stdin data, and buffer | |
1398 | * them for sending to the server. | |
1399 | */ | |
1400 | if (!compat20) | |
1401 | client_make_packets_from_stdin_data(); | |
1402 | ||
1403 | /* | |
1404 | * Make packets from buffered channel data, and | |
1405 | * enqueue them for sending to the server. | |
1406 | */ | |
1407 | if (packet_not_very_much_data_to_write()) | |
1408 | channel_output_poll(); | |
1409 | ||
1410 | /* | |
1411 | * Check if the window size has changed, and buffer a | |
1412 | * message about it to the server if so. | |
1413 | */ | |
1414 | client_check_window_change(); | |
1415 | ||
1416 | if (quit_pending) | |
1417 | break; | |
1418 | } | |
1419 | /* | |
1420 | * Wait until we have something to do (something becomes | |
1421 | * available on one of the descriptors). | |
1422 | */ | |
1423 | max_fd2 = max_fd; | |
1424 | client_wait_until_can_do_something(&readset, &writeset, | |
1425 | &max_fd2, &nalloc, rekeying); | |
1426 | ||
1427 | if (quit_pending) | |
1428 | break; | |
1429 | ||
1430 | /* Do channel operations unless rekeying in progress. */ | |
1431 | if (!rekeying) { | |
1432 | channel_after_select(readset, writeset); | |
1433 | if (need_rekeying || packet_need_rekeying()) { | |
1434 | debug("need rekeying"); | |
1435 | xxx_kex->done = 0; | |
1436 | kex_send_kexinit(xxx_kex); | |
1437 | need_rekeying = 0; | |
1438 | } | |
1439 | } | |
1440 | ||
1441 | /* Buffer input from the connection. */ | |
1442 | client_process_net_input(readset); | |
1443 | ||
1444 | /* Accept control connections. */ | |
1445 | if (muxserver_sock != -1 &&FD_ISSET(muxserver_sock, readset)) { | |
1446 | if (muxserver_accept_control()) | |
1447 | quit_pending = 1; | |
1448 | } | |
1449 | ||
1450 | if (quit_pending) | |
1451 | break; | |
1452 | ||
1453 | if (!compat20) { | |
1454 | /* Buffer data from stdin */ | |
1455 | client_process_input(readset); | |
1456 | /* | |
1457 | * Process output to stdout and stderr. Output to | |
1458 | * the connection is processed elsewhere (above). | |
1459 | */ | |
1460 | client_process_output(writeset); | |
1461 | } | |
1462 | ||
1463 | /* | |
1464 | * Send as much buffered packet data as possible to the | |
1465 | * sender. | |
1466 | */ | |
1467 | if (FD_ISSET(connection_out, writeset)) | |
1468 | packet_write_poll(); | |
1469 | } | |
1470 | if (readset) | |
1471 | xfree(readset); | |
1472 | if (writeset) | |
1473 | xfree(writeset); | |
1474 | ||
1475 | /* Terminate the session. */ | |
1476 | ||
1477 | /* Stop watching for window change. */ | |
1478 | signal(SIGWINCH, SIG_DFL); | |
1479 | ||
1480 | if (compat20) { | |
1481 | packet_start(SSH2_MSG_DISCONNECT); | |
1482 | packet_put_int(SSH2_DISCONNECT_BY_APPLICATION); | |
1483 | packet_put_cstring("disconnected by user"); | |
1484 | packet_send(); | |
1485 | packet_write_wait(); | |
1486 | } | |
1487 | ||
1488 | channel_free_all(); | |
1489 | ||
1490 | if (have_pty) | |
1491 | leave_raw_mode(); | |
1492 | ||
1493 | /* restore blocking io */ | |
1494 | if (!isatty(fileno(stdin))) | |
1495 | unset_nonblock(fileno(stdin)); | |
1496 | if (!isatty(fileno(stdout))) | |
1497 | unset_nonblock(fileno(stdout)); | |
1498 | if (!isatty(fileno(stderr))) | |
1499 | unset_nonblock(fileno(stderr)); | |
1500 | ||
1501 | /* | |
1502 | * If there was no shell or command requested, there will be no remote | |
1503 | * exit status to be returned. In that case, clear error code if the | |
1504 | * connection was deliberately terminated at this end. | |
1505 | */ | |
1506 | if (no_shell_flag && received_signal == SIGTERM) { | |
1507 | received_signal = 0; | |
1508 | exit_status = 0; | |
1509 | } | |
1510 | ||
1511 | if (received_signal) | |
1512 | fatal("Killed by signal %d.", (int) received_signal); | |
1513 | ||
1514 | /* | |
1515 | * In interactive mode (with pseudo tty) display a message indicating | |
1516 | * that the connection has been closed. | |
1517 | */ | |
1518 | if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) { | |
1519 | snprintf(buf, sizeof buf, | |
1520 | "Connection to %.64s closed.\r\n", host); | |
1521 | buffer_append(&stderr_buffer, buf, strlen(buf)); | |
1522 | } | |
1523 | ||
1524 | /* Output any buffered data for stdout. */ | |
1525 | while (buffer_len(&stdout_buffer) > 0) { | |
1526 | len = write(fileno(stdout), buffer_ptr(&stdout_buffer), | |
1527 | buffer_len(&stdout_buffer)); | |
1528 | if (len <= 0) { | |
1529 | error("Write failed flushing stdout buffer."); | |
1530 | break; | |
1531 | } | |
1532 | buffer_consume(&stdout_buffer, len); | |
1533 | } | |
1534 | ||
1535 | /* Output any buffered data for stderr. */ | |
1536 | while (buffer_len(&stderr_buffer) > 0) { | |
1537 | len = write(fileno(stderr), buffer_ptr(&stderr_buffer), | |
1538 | buffer_len(&stderr_buffer)); | |
1539 | if (len <= 0) { | |
1540 | error("Write failed flushing stderr buffer."); | |
1541 | break; | |
1542 | } | |
1543 | buffer_consume(&stderr_buffer, len); | |
1544 | } | |
1545 | ||
1546 | /* Clear and free any buffers. */ | |
1547 | memset(buf, 0, sizeof(buf)); | |
1548 | buffer_free(&stdin_buffer); | |
1549 | buffer_free(&stdout_buffer); | |
1550 | buffer_free(&stderr_buffer); | |
1551 | ||
1552 | /* Report bytes transferred, and transfer rates. */ | |
1553 | total_time = get_current_time() - start_time; | |
1554 | packet_get_state(MODE_IN, NULL, NULL, NULL, &ibytes); | |
1555 | packet_get_state(MODE_OUT, NULL, NULL, NULL, &obytes); | |
1556 | verbose("Transferred: sent %llu, received %llu bytes, in %.1f seconds", | |
1557 | obytes, ibytes, total_time); | |
1558 | if (total_time > 0) | |
1559 | verbose("Bytes per second: sent %.1f, received %.1f", | |
1560 | obytes / total_time, ibytes / total_time); | |
1561 | /* Return the exit status of the program. */ | |
1562 | debug("Exit status %d", exit_status); | |
1563 | return exit_status; | |
1564 | } | |
1565 | ||
1566 | /*********/ | |
1567 | ||
1568 | static void | |
1569 | client_input_stdout_data(int type, u_int32_t seq, void *ctxt) | |
1570 | { | |
1571 | u_int data_len; | |
1572 | char *data = packet_get_string(&data_len); | |
1573 | packet_check_eom(); | |
1574 | buffer_append(&stdout_buffer, data, data_len); | |
1575 | memset(data, 0, data_len); | |
1576 | xfree(data); | |
1577 | } | |
1578 | static void | |
1579 | client_input_stderr_data(int type, u_int32_t seq, void *ctxt) | |
1580 | { | |
1581 | u_int data_len; | |
1582 | char *data = packet_get_string(&data_len); | |
1583 | packet_check_eom(); | |
1584 | buffer_append(&stderr_buffer, data, data_len); | |
1585 | memset(data, 0, data_len); | |
1586 | xfree(data); | |
1587 | } | |
1588 | static void | |
1589 | client_input_exit_status(int type, u_int32_t seq, void *ctxt) | |
1590 | { | |
1591 | exit_status = packet_get_int(); | |
1592 | packet_check_eom(); | |
1593 | /* Acknowledge the exit. */ | |
1594 | packet_start(SSH_CMSG_EXIT_CONFIRMATION); | |
1595 | packet_send(); | |
1596 | /* | |
1597 | * Must wait for packet to be sent since we are | |
1598 | * exiting the loop. | |
1599 | */ | |
1600 | packet_write_wait(); | |
1601 | /* Flag that we want to exit. */ | |
1602 | quit_pending = 1; | |
1603 | } | |
1604 | static void | |
1605 | client_input_agent_open(int type, u_int32_t seq, void *ctxt) | |
1606 | { | |
1607 | Channel *c = NULL; | |
1608 | int remote_id, sock; | |
1609 | ||
1610 | /* Read the remote channel number from the message. */ | |
1611 | remote_id = packet_get_int(); | |
1612 | packet_check_eom(); | |
1613 | ||
1614 | /* | |
1615 | * Get a connection to the local authentication agent (this may again | |
1616 | * get forwarded). | |
1617 | */ | |
1618 | sock = ssh_get_authentication_socket(); | |
1619 | ||
1620 | /* | |
1621 | * If we could not connect the agent, send an error message back to | |
1622 | * the server. This should never happen unless the agent dies, | |
1623 | * because authentication forwarding is only enabled if we have an | |
1624 | * agent. | |
1625 | */ | |
1626 | if (sock >= 0) { | |
1627 | c = channel_new("", SSH_CHANNEL_OPEN, sock, sock, | |
1628 | -1, 0, 0, 0, "authentication agent connection", 1); | |
1629 | c->remote_id = remote_id; | |
1630 | c->force_drain = 1; | |
1631 | } | |
1632 | if (c == NULL) { | |
1633 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
1634 | packet_put_int(remote_id); | |
1635 | } else { | |
1636 | /* Send a confirmation to the remote host. */ | |
1637 | debug("Forwarding authentication connection."); | |
1638 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1639 | packet_put_int(remote_id); | |
1640 | packet_put_int(c->self); | |
1641 | } | |
1642 | packet_send(); | |
1643 | } | |
1644 | ||
1645 | static Channel * | |
1646 | client_request_forwarded_tcpip(const char *request_type, int rchan) | |
1647 | { | |
1648 | Channel *c = NULL; | |
1649 | char *listen_address, *originator_address; | |
1650 | u_short listen_port, originator_port; | |
1651 | ||
1652 | /* Get rest of the packet */ | |
1653 | listen_address = packet_get_string(NULL); | |
1654 | listen_port = packet_get_int(); | |
1655 | originator_address = packet_get_string(NULL); | |
1656 | originator_port = packet_get_int(); | |
1657 | packet_check_eom(); | |
1658 | ||
1659 | debug("client_request_forwarded_tcpip: listen %s port %d, " | |
1660 | "originator %s port %d", listen_address, listen_port, | |
1661 | originator_address, originator_port); | |
1662 | ||
1663 | c = channel_connect_by_listen_address(listen_port, | |
1664 | "forwarded-tcpip", originator_address); | |
1665 | ||
1666 | xfree(originator_address); | |
1667 | xfree(listen_address); | |
1668 | return c; | |
1669 | } | |
1670 | ||
1671 | static Channel * | |
1672 | client_request_x11(const char *request_type, int rchan) | |
1673 | { | |
1674 | Channel *c = NULL; | |
1675 | char *originator; | |
1676 | u_short originator_port; | |
1677 | int sock; | |
1678 | ||
1679 | if (!options.forward_x11) { | |
1680 | error("Warning: ssh server tried X11 forwarding."); | |
1681 | error("Warning: this is probably a break-in attempt by a " | |
1682 | "malicious server."); | |
1683 | return NULL; | |
1684 | } | |
1685 | originator = packet_get_string(NULL); | |
1686 | if (datafellows & SSH_BUG_X11FWD) { | |
1687 | debug2("buggy server: x11 request w/o originator_port"); | |
1688 | originator_port = 0; | |
1689 | } else { | |
1690 | originator_port = packet_get_int(); | |
1691 | } | |
1692 | packet_check_eom(); | |
1693 | /* XXX check permission */ | |
1694 | debug("client_request_x11: request from %s %d", originator, | |
1695 | originator_port); | |
1696 | xfree(originator); | |
1697 | sock = x11_connect_display(); | |
1698 | if (sock < 0) | |
1699 | return NULL; | |
1700 | c = channel_new("x11", | |
1701 | SSH_CHANNEL_X11_OPEN, sock, sock, -1, | |
1702 | CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1); | |
1703 | c->force_drain = 1; | |
1704 | return c; | |
1705 | } | |
1706 | ||
1707 | static Channel * | |
1708 | client_request_agent(const char *request_type, int rchan) | |
1709 | { | |
1710 | Channel *c = NULL; | |
1711 | int sock; | |
1712 | ||
1713 | if (!options.forward_agent) { | |
1714 | error("Warning: ssh server tried agent forwarding."); | |
1715 | error("Warning: this is probably a break-in attempt by a " | |
1716 | "malicious server."); | |
1717 | return NULL; | |
1718 | } | |
1719 | sock = ssh_get_authentication_socket(); | |
1720 | if (sock < 0) | |
1721 | return NULL; | |
1722 | c = channel_new("authentication agent connection", | |
1723 | SSH_CHANNEL_OPEN, sock, sock, -1, | |
1724 | CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, | |
1725 | "authentication agent connection", 1); | |
1726 | c->force_drain = 1; | |
1727 | return c; | |
1728 | } | |
1729 | ||
1730 | int | |
1731 | client_request_tun_fwd(int tun_mode, int local_tun, int remote_tun) | |
1732 | { | |
1733 | Channel *c; | |
1734 | int fd; | |
1735 | ||
1736 | if (tun_mode == SSH_TUNMODE_NO) | |
1737 | return 0; | |
1738 | ||
1739 | if (!compat20) { | |
1740 | error("Tunnel forwarding is not supported for protocol 1"); | |
1741 | return -1; | |
1742 | } | |
1743 | ||
1744 | debug("Requesting tun unit %d in mode %d", local_tun, tun_mode); | |
1745 | ||
1746 | /* Open local tunnel device */ | |
1747 | if ((fd = tun_open(local_tun, tun_mode)) == -1) { | |
1748 | error("Tunnel device open failed."); | |
1749 | return -1; | |
1750 | } | |
1751 | ||
1752 | c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1, | |
1753 | CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, "tun", 1); | |
1754 | c->datagram = 1; | |
1755 | ||
1756 | #if defined(SSH_TUN_FILTER) | |
1757 | if (options.tun_open == SSH_TUNMODE_POINTOPOINT) | |
1758 | channel_register_filter(c->self, sys_tun_infilter, | |
1759 | sys_tun_outfilter, NULL, NULL); | |
1760 | #endif | |
1761 | ||
1762 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
1763 | packet_put_cstring("tun@openssh.com"); | |
1764 | packet_put_int(c->self); | |
1765 | packet_put_int(c->local_window_max); | |
1766 | packet_put_int(c->local_maxpacket); | |
1767 | packet_put_int(tun_mode); | |
1768 | packet_put_int(remote_tun); | |
1769 | packet_send(); | |
1770 | ||
1771 | return 0; | |
1772 | } | |
1773 | ||
1774 | /* XXXX move to generic input handler */ | |
1775 | static void | |
1776 | client_input_channel_open(int type, u_int32_t seq, void *ctxt) | |
1777 | { | |
1778 | Channel *c = NULL; | |
1779 | char *ctype; | |
1780 | int rchan; | |
1781 | u_int rmaxpack, rwindow, len; | |
1782 | ||
1783 | ctype = packet_get_string(&len); | |
1784 | rchan = packet_get_int(); | |
1785 | rwindow = packet_get_int(); | |
1786 | rmaxpack = packet_get_int(); | |
1787 | ||
1788 | debug("client_input_channel_open: ctype %s rchan %d win %d max %d", | |
1789 | ctype, rchan, rwindow, rmaxpack); | |
1790 | ||
1791 | if (strcmp(ctype, "forwarded-tcpip") == 0) { | |
1792 | c = client_request_forwarded_tcpip(ctype, rchan); | |
1793 | } else if (strcmp(ctype, "x11") == 0) { | |
1794 | c = client_request_x11(ctype, rchan); | |
1795 | } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) { | |
1796 | c = client_request_agent(ctype, rchan); | |
1797 | } | |
1798 | /* XXX duplicate : */ | |
1799 | if (c != NULL) { | |
1800 | debug("confirm %s", ctype); | |
1801 | c->remote_id = rchan; | |
1802 | c->remote_window = rwindow; | |
1803 | c->remote_maxpacket = rmaxpack; | |
1804 | if (c->type != SSH_CHANNEL_CONNECTING) { | |
1805 | packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1806 | packet_put_int(c->remote_id); | |
1807 | packet_put_int(c->self); | |
1808 | packet_put_int(c->local_window); | |
1809 | packet_put_int(c->local_maxpacket); | |
1810 | packet_send(); | |
1811 | } | |
1812 | } else { | |
1813 | debug("failure %s", ctype); | |
1814 | packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE); | |
1815 | packet_put_int(rchan); | |
1816 | packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED); | |
1817 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { | |
1818 | packet_put_cstring("open failed"); | |
1819 | packet_put_cstring(""); | |
1820 | } | |
1821 | packet_send(); | |
1822 | } | |
1823 | xfree(ctype); | |
1824 | } | |
1825 | static void | |
1826 | client_input_channel_req(int type, u_int32_t seq, void *ctxt) | |
1827 | { | |
1828 | Channel *c = NULL; | |
1829 | int exitval, id, reply, success = 0; | |
1830 | char *rtype; | |
1831 | ||
1832 | id = packet_get_int(); | |
1833 | rtype = packet_get_string(NULL); | |
1834 | reply = packet_get_char(); | |
1835 | ||
1836 | debug("client_input_channel_req: channel %d rtype %s reply %d", | |
1837 | id, rtype, reply); | |
1838 | ||
1839 | if (id == -1) { | |
1840 | error("client_input_channel_req: request for channel -1"); | |
1841 | } else if ((c = channel_lookup(id)) == NULL) { | |
1842 | error("client_input_channel_req: channel %d: " | |
1843 | "unknown channel", id); | |
1844 | } else if (strcmp(rtype, "eow@openssh.com") == 0) { | |
1845 | packet_check_eom(); | |
1846 | chan_rcvd_eow(c); | |
1847 | } else if (strcmp(rtype, "exit-status") == 0) { | |
1848 | exitval = packet_get_int(); | |
1849 | if (id == session_ident) { | |
1850 | success = 1; | |
1851 | exit_status = exitval; | |
1852 | } else if (c->ctl_fd == -1) { | |
1853 | error("client_input_channel_req: unexpected channel %d", | |
1854 | session_ident); | |
1855 | } else { | |
1856 | atomicio(vwrite, c->ctl_fd, &exitval, sizeof(exitval)); | |
1857 | success = 1; | |
1858 | } | |
1859 | packet_check_eom(); | |
1860 | } | |
1861 | if (reply) { | |
1862 | packet_start(success ? | |
1863 | SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE); | |
1864 | packet_put_int(c->remote_id); | |
1865 | packet_send(); | |
1866 | } | |
1867 | xfree(rtype); | |
1868 | } | |
1869 | static void | |
1870 | client_input_global_request(int type, u_int32_t seq, void *ctxt) | |
1871 | { | |
1872 | char *rtype; | |
1873 | int want_reply; | |
1874 | int success = 0; | |
1875 | ||
1876 | rtype = packet_get_string(NULL); | |
1877 | want_reply = packet_get_char(); | |
1878 | debug("client_input_global_request: rtype %s want_reply %d", | |
1879 | rtype, want_reply); | |
1880 | if (want_reply) { | |
1881 | packet_start(success ? | |
1882 | SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE); | |
1883 | packet_send(); | |
1884 | packet_write_wait(); | |
1885 | } | |
1886 | xfree(rtype); | |
1887 | } | |
1888 | ||
1889 | void | |
1890 | client_session2_setup(int id, int want_tty, int want_subsystem, | |
1891 | const char *term, struct termios *tiop, int in_fd, Buffer *cmd, char **env) | |
1892 | { | |
1893 | int len; | |
1894 | Channel *c = NULL; | |
1895 | ||
1896 | debug2("%s: id %d", __func__, id); | |
1897 | ||
1898 | if ((c = channel_lookup(id)) == NULL) | |
1899 | fatal("client_session2_setup: channel %d: unknown channel", id); | |
1900 | ||
1901 | if (want_tty) { | |
1902 | struct winsize ws; | |
1903 | ||
1904 | /* Store window size in the packet. */ | |
1905 | if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0) | |
1906 | memset(&ws, 0, sizeof(ws)); | |
1907 | ||
1908 | channel_request_start(id, "pty-req", 1); | |
1909 | client_expect_confirm(id, "PTY allocation", 0); | |
1910 | packet_put_cstring(term != NULL ? term : ""); | |
1911 | packet_put_int((u_int)ws.ws_col); | |
1912 | packet_put_int((u_int)ws.ws_row); | |
1913 | packet_put_int((u_int)ws.ws_xpixel); | |
1914 | packet_put_int((u_int)ws.ws_ypixel); | |
1915 | if (tiop == NULL) | |
1916 | tiop = get_saved_tio(); | |
1917 | tty_make_modes(-1, tiop); | |
1918 | packet_send(); | |
1919 | /* XXX wait for reply */ | |
1920 | c->client_tty = 1; | |
1921 | } | |
1922 | ||
1923 | /* Transfer any environment variables from client to server */ | |
1924 | if (options.num_send_env != 0 && env != NULL) { | |
1925 | int i, j, matched; | |
1926 | char *name, *val; | |
1927 | ||
1928 | debug("Sending environment."); | |
1929 | for (i = 0; env[i] != NULL; i++) { | |
1930 | /* Split */ | |
1931 | name = xstrdup(env[i]); | |
1932 | if ((val = strchr(name, '=')) == NULL) { | |
1933 | xfree(name); | |
1934 | continue; | |
1935 | } | |
1936 | *val++ = '\0'; | |
1937 | ||
1938 | matched = 0; | |
1939 | for (j = 0; j < options.num_send_env; j++) { | |
1940 | if (match_pattern(name, options.send_env[j])) { | |
1941 | matched = 1; | |
1942 | break; | |
1943 | } | |
1944 | } | |
1945 | if (!matched) { | |
1946 | debug3("Ignored env %s", name); | |
1947 | xfree(name); | |
1948 | continue; | |
1949 | } | |
1950 | ||
1951 | debug("Sending env %s = %s", name, val); | |
1952 | channel_request_start(id, "env", 0); | |
1953 | packet_put_cstring(name); | |
1954 | packet_put_cstring(val); | |
1955 | packet_send(); | |
1956 | xfree(name); | |
1957 | } | |
1958 | } | |
1959 | ||
1960 | len = buffer_len(cmd); | |
1961 | if (len > 0) { | |
1962 | if (len > 900) | |
1963 | len = 900; | |
1964 | if (want_subsystem) { | |
1965 | debug("Sending subsystem: %.*s", | |
1966 | len, (u_char*)buffer_ptr(cmd)); | |
1967 | channel_request_start(id, "subsystem", 1); | |
1968 | client_expect_confirm(id, "subsystem", 1); | |
1969 | } else { | |
1970 | debug("Sending command: %.*s", | |
1971 | len, (u_char*)buffer_ptr(cmd)); | |
1972 | channel_request_start(id, "exec", 1); | |
1973 | client_expect_confirm(id, "exec", 1); | |
1974 | } | |
1975 | packet_put_string(buffer_ptr(cmd), buffer_len(cmd)); | |
1976 | packet_send(); | |
1977 | } else { | |
1978 | channel_request_start(id, "shell", 1); | |
1979 | client_expect_confirm(id, "shell", 1); | |
1980 | packet_send(); | |
1981 | } | |
1982 | } | |
1983 | ||
1984 | static void | |
1985 | client_init_dispatch_20(void) | |
1986 | { | |
1987 | dispatch_init(&dispatch_protocol_error); | |
1988 | ||
1989 | dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose); | |
1990 | dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data); | |
1991 | dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof); | |
1992 | dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data); | |
1993 | dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open); | |
1994 | dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation); | |
1995 | dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure); | |
1996 | dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req); | |
1997 | dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust); | |
1998 | dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &channel_input_status_confirm); | |
1999 | dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &channel_input_status_confirm); | |
2000 | dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request); | |
2001 | ||
2002 | /* rekeying */ | |
2003 | dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit); | |
2004 | ||
2005 | /* global request reply messages */ | |
2006 | dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply); | |
2007 | dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply); | |
2008 | } | |
2009 | ||
2010 | static void | |
2011 | client_init_dispatch_13(void) | |
2012 | { | |
2013 | dispatch_init(NULL); | |
2014 | dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close); | |
2015 | dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation); | |
2016 | dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data); | |
2017 | dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation); | |
2018 | dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure); | |
2019 | dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open); | |
2020 | dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status); | |
2021 | dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data); | |
2022 | dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data); | |
2023 | ||
2024 | dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ? | |
2025 | &client_input_agent_open : &deny_input_open); | |
2026 | dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ? | |
2027 | &x11_input_open : &deny_input_open); | |
2028 | } | |
2029 | ||
2030 | static void | |
2031 | client_init_dispatch_15(void) | |
2032 | { | |
2033 | client_init_dispatch_13(); | |
2034 | dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof); | |
2035 | dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose); | |
2036 | } | |
2037 | ||
2038 | static void | |
2039 | client_init_dispatch(void) | |
2040 | { | |
2041 | if (compat20) | |
2042 | client_init_dispatch_20(); | |
2043 | else if (compat13) | |
2044 | client_init_dispatch_13(); | |
2045 | else | |
2046 | client_init_dispatch_15(); | |
2047 | } | |
2048 | ||
2049 | /* client specific fatal cleanup */ | |
2050 | void | |
2051 | cleanup_exit(int i) | |
2052 | { | |
2053 | leave_raw_mode(); | |
2054 | leave_non_blocking(); | |
2055 | if (options.control_path != NULL && muxserver_sock != -1) | |
2056 | unlink(options.control_path); | |
2057 | _exit(i); | |
2058 | } |