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799ae497 | 1 | /* $OpenBSD: clientloop.c,v 1.178 2007/02/20 10:25:14 djm Exp $ */ |
3c0ef626 | 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" | |
3c0ef626 | 63 | |
9108f8d9 | 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 "xmalloc.h" | |
3c0ef626 | 90 | #include "ssh.h" |
91 | #include "ssh1.h" | |
92 | #include "ssh2.h" | |
3c0ef626 | 93 | #include "packet.h" |
94 | #include "buffer.h" | |
95 | #include "compat.h" | |
96 | #include "channels.h" | |
97 | #include "dispatch.h" | |
3c0ef626 | 98 | #include "key.h" |
9108f8d9 | 99 | #include "cipher.h" |
3c0ef626 | 100 | #include "kex.h" |
101 | #include "log.h" | |
102 | #include "readconf.h" | |
103 | #include "clientloop.h" | |
2c06c99b | 104 | #include "sshconnect.h" |
3c0ef626 | 105 | #include "authfd.h" |
106 | #include "atomicio.h" | |
c9f39d2c | 107 | #include "sshpty.h" |
3c0ef626 | 108 | #include "misc.h" |
c9f39d2c | 109 | #include "monitor_fdpass.h" |
110 | #include "match.h" | |
111 | #include "msg.h" | |
3c0ef626 | 112 | |
113 | /* import options */ | |
114 | extern Options options; | |
115 | ||
116 | /* Flag indicating that stdin should be redirected from /dev/null. */ | |
117 | extern int stdin_null_flag; | |
118 | ||
cdd66111 | 119 | /* Flag indicating that no shell has been requested */ |
120 | extern int no_shell_flag; | |
121 | ||
c9f39d2c | 122 | /* Control socket */ |
123 | extern int control_fd; | |
124 | ||
3c0ef626 | 125 | /* |
126 | * Name of the host we are connecting to. This is the name given on the | |
127 | * command line, or the HostName specified for the user-supplied name in a | |
128 | * configuration file. | |
129 | */ | |
130 | extern char *host; | |
131 | ||
132 | /* | |
133 | * Flag to indicate that we have received a window change signal which has | |
134 | * not yet been processed. This will cause a message indicating the new | |
135 | * window size to be sent to the server a little later. This is volatile | |
136 | * because this is updated in a signal handler. | |
137 | */ | |
e9a17296 | 138 | static volatile sig_atomic_t received_window_change_signal = 0; |
139 | static volatile sig_atomic_t received_signal = 0; | |
3c0ef626 | 140 | |
2c06c99b | 141 | /* Flag indicating whether the user's terminal is in non-blocking mode. */ |
3c0ef626 | 142 | static int in_non_blocking_mode = 0; |
143 | ||
144 | /* Common data for the client loop code. */ | |
9108f8d9 | 145 | static volatile sig_atomic_t quit_pending; /* Set non-zero to quit the loop. */ |
3c0ef626 | 146 | static int escape_char; /* Escape character. */ |
147 | static int escape_pending; /* Last character was the escape character */ | |
148 | static int last_was_cr; /* Last character was a newline. */ | |
149 | static int exit_status; /* Used to store the exit status of the command. */ | |
150 | static int stdin_eof; /* EOF has been encountered on standard error. */ | |
151 | static Buffer stdin_buffer; /* Buffer for stdin data. */ | |
152 | static Buffer stdout_buffer; /* Buffer for stdout data. */ | |
153 | static Buffer stderr_buffer; /* Buffer for stderr data. */ | |
154 | static u_long stdin_bytes, stdout_bytes, stderr_bytes; | |
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. */ | |
cdd66111 | 160 | static int server_alive_timeouts = 0; |
3c0ef626 | 161 | |
162 | static void client_init_dispatch(void); | |
163 | int session_ident = -1; | |
164 | ||
c9f39d2c | 165 | struct confirm_ctx { |
166 | int want_tty; | |
167 | int want_subsys; | |
665a873d | 168 | int want_x_fwd; |
169 | int want_agent_fwd; | |
c9f39d2c | 170 | Buffer cmd; |
171 | char *term; | |
172 | struct termios tio; | |
173 | char **env; | |
174 | }; | |
175 | ||
3c0ef626 | 176 | /*XXX*/ |
177 | extern Kex *xxx_kex; | |
178 | ||
c9f39d2c | 179 | void ssh_process_session2_setup(int, int, int, Buffer *); |
180 | ||
3c0ef626 | 181 | /* Restores stdin to blocking mode. */ |
182 | ||
183 | static void | |
184 | leave_non_blocking(void) | |
185 | { | |
186 | if (in_non_blocking_mode) { | |
c9f39d2c | 187 | unset_nonblock(fileno(stdin)); |
3c0ef626 | 188 | in_non_blocking_mode = 0; |
3c0ef626 | 189 | } |
190 | } | |
191 | ||
192 | /* Puts stdin terminal in non-blocking mode. */ | |
193 | ||
194 | static void | |
195 | enter_non_blocking(void) | |
196 | { | |
197 | in_non_blocking_mode = 1; | |
c9f39d2c | 198 | set_nonblock(fileno(stdin)); |
3c0ef626 | 199 | } |
200 | ||
201 | /* | |
202 | * Signal handler for the window change signal (SIGWINCH). This just sets a | |
203 | * flag indicating that the window has changed. | |
204 | */ | |
9108f8d9 | 205 | /*ARGSUSED */ |
3c0ef626 | 206 | static void |
207 | window_change_handler(int sig) | |
208 | { | |
209 | received_window_change_signal = 1; | |
210 | signal(SIGWINCH, window_change_handler); | |
211 | } | |
212 | ||
213 | /* | |
214 | * Signal handler for signals that cause the program to terminate. These | |
215 | * signals must be trapped to restore terminal modes. | |
216 | */ | |
9108f8d9 | 217 | /*ARGSUSED */ |
3c0ef626 | 218 | static void |
219 | signal_handler(int sig) | |
220 | { | |
221 | received_signal = sig; | |
222 | quit_pending = 1; | |
223 | } | |
224 | ||
225 | /* | |
226 | * Returns current time in seconds from Jan 1, 1970 with the maximum | |
227 | * available resolution. | |
228 | */ | |
229 | ||
230 | static double | |
231 | get_current_time(void) | |
232 | { | |
233 | struct timeval tv; | |
234 | gettimeofday(&tv, NULL); | |
235 | return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0; | |
236 | } | |
237 | ||
665a873d | 238 | #define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1" |
239 | void | |
240 | client_x11_get_proto(const char *display, const char *xauth_path, | |
241 | u_int trusted, char **_proto, char **_data) | |
242 | { | |
243 | char cmd[1024]; | |
244 | char line[512]; | |
245 | char xdisplay[512]; | |
246 | static char proto[512], data[512]; | |
247 | FILE *f; | |
248 | int got_data = 0, generated = 0, do_unlink = 0, i; | |
249 | char *xauthdir, *xauthfile; | |
250 | struct stat st; | |
251 | ||
252 | xauthdir = xauthfile = NULL; | |
253 | *_proto = proto; | |
254 | *_data = data; | |
255 | proto[0] = data[0] = '\0'; | |
256 | ||
257 | if (xauth_path == NULL ||(stat(xauth_path, &st) == -1)) { | |
258 | debug("No xauth program."); | |
259 | } else { | |
260 | if (display == NULL) { | |
261 | debug("x11_get_proto: DISPLAY not set"); | |
262 | return; | |
263 | } | |
264 | /* | |
265 | * Handle FamilyLocal case where $DISPLAY does | |
266 | * not match an authorization entry. For this we | |
267 | * just try "xauth list unix:displaynum.screennum". | |
268 | * XXX: "localhost" match to determine FamilyLocal | |
269 | * is not perfect. | |
270 | */ | |
271 | if (strncmp(display, "localhost:", 10) == 0) { | |
272 | snprintf(xdisplay, sizeof(xdisplay), "unix:%s", | |
273 | display + 10); | |
274 | display = xdisplay; | |
275 | } | |
276 | if (trusted == 0) { | |
277 | xauthdir = xmalloc(MAXPATHLEN); | |
278 | xauthfile = xmalloc(MAXPATHLEN); | |
279 | strlcpy(xauthdir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN); | |
280 | if (mkdtemp(xauthdir) != NULL) { | |
281 | do_unlink = 1; | |
282 | snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile", | |
283 | xauthdir); | |
284 | snprintf(cmd, sizeof(cmd), | |
285 | "%s -f %s generate %s " SSH_X11_PROTO | |
286 | " untrusted timeout 1200 2>" _PATH_DEVNULL, | |
287 | xauth_path, xauthfile, display); | |
288 | debug2("x11_get_proto: %s", cmd); | |
289 | if (system(cmd) == 0) | |
290 | generated = 1; | |
291 | } | |
292 | } | |
293 | snprintf(cmd, sizeof(cmd), | |
2c06c99b | 294 | "%s %s%s list %s 2>" _PATH_DEVNULL, |
665a873d | 295 | xauth_path, |
296 | generated ? "-f " : "" , | |
297 | generated ? xauthfile : "", | |
298 | display); | |
299 | debug2("x11_get_proto: %s", cmd); | |
300 | f = popen(cmd, "r"); | |
301 | if (f && fgets(line, sizeof(line), f) && | |
302 | sscanf(line, "%*s %511s %511s", proto, data) == 2) | |
303 | got_data = 1; | |
304 | if (f) | |
305 | pclose(f); | |
306 | } | |
307 | ||
308 | if (do_unlink) { | |
309 | unlink(xauthfile); | |
310 | rmdir(xauthdir); | |
311 | } | |
312 | if (xauthdir) | |
313 | xfree(xauthdir); | |
314 | if (xauthfile) | |
315 | xfree(xauthfile); | |
316 | ||
317 | /* | |
318 | * If we didn't get authentication data, just make up some | |
319 | * data. The forwarding code will check the validity of the | |
320 | * response anyway, and substitute this data. The X11 | |
321 | * server, however, will ignore this fake data and use | |
322 | * whatever authentication mechanisms it was using otherwise | |
323 | * for the local connection. | |
324 | */ | |
325 | if (!got_data) { | |
326 | u_int32_t rnd = 0; | |
327 | ||
328 | logit("Warning: No xauth data; " | |
329 | "using fake authentication data for X11 forwarding."); | |
330 | strlcpy(proto, SSH_X11_PROTO, sizeof proto); | |
331 | for (i = 0; i < 16; i++) { | |
332 | if (i % 4 == 0) | |
333 | rnd = arc4random(); | |
334 | snprintf(data + 2 * i, sizeof data - 2 * i, "%02x", | |
335 | rnd & 0xff); | |
336 | rnd >>= 8; | |
337 | } | |
338 | } | |
339 | } | |
340 | ||
3c0ef626 | 341 | /* |
342 | * This is called when the interactive is entered. This checks if there is | |
343 | * an EOF coming on stdin. We must check this explicitly, as select() does | |
344 | * not appear to wake up when redirecting from /dev/null. | |
345 | */ | |
346 | ||
347 | static void | |
348 | client_check_initial_eof_on_stdin(void) | |
349 | { | |
350 | int len; | |
351 | char buf[1]; | |
352 | ||
353 | /* | |
354 | * If standard input is to be "redirected from /dev/null", we simply | |
355 | * mark that we have seen an EOF and send an EOF message to the | |
356 | * server. Otherwise, we try to read a single character; it appears | |
357 | * that for some files, such /dev/null, select() never wakes up for | |
358 | * read for this descriptor, which means that we never get EOF. This | |
359 | * way we will get the EOF if stdin comes from /dev/null or similar. | |
360 | */ | |
361 | if (stdin_null_flag) { | |
362 | /* Fake EOF on stdin. */ | |
363 | debug("Sending eof."); | |
364 | stdin_eof = 1; | |
365 | packet_start(SSH_CMSG_EOF); | |
366 | packet_send(); | |
367 | } else { | |
368 | enter_non_blocking(); | |
369 | ||
370 | /* Check for immediate EOF on stdin. */ | |
371 | len = read(fileno(stdin), buf, 1); | |
372 | if (len == 0) { | |
373 | /* EOF. Record that we have seen it and send EOF to server. */ | |
374 | debug("Sending eof."); | |
375 | stdin_eof = 1; | |
376 | packet_start(SSH_CMSG_EOF); | |
377 | packet_send(); | |
378 | } else if (len > 0) { | |
379 | /* | |
380 | * Got data. We must store the data in the buffer, | |
381 | * and also process it as an escape character if | |
382 | * appropriate. | |
383 | */ | |
384 | if ((u_char) buf[0] == escape_char) | |
385 | escape_pending = 1; | |
386 | else | |
387 | buffer_append(&stdin_buffer, buf, 1); | |
388 | } | |
389 | leave_non_blocking(); | |
390 | } | |
391 | } | |
392 | ||
393 | ||
394 | /* | |
395 | * Make packets from buffered stdin data, and buffer them for sending to the | |
396 | * connection. | |
397 | */ | |
398 | ||
399 | static void | |
400 | client_make_packets_from_stdin_data(void) | |
401 | { | |
402 | u_int len; | |
403 | ||
404 | /* Send buffered stdin data to the server. */ | |
405 | while (buffer_len(&stdin_buffer) > 0 && | |
e9a17296 | 406 | packet_not_very_much_data_to_write()) { |
3c0ef626 | 407 | len = buffer_len(&stdin_buffer); |
408 | /* Keep the packets at reasonable size. */ | |
409 | if (len > packet_get_maxsize()) | |
410 | len = packet_get_maxsize(); | |
411 | packet_start(SSH_CMSG_STDIN_DATA); | |
412 | packet_put_string(buffer_ptr(&stdin_buffer), len); | |
413 | packet_send(); | |
414 | buffer_consume(&stdin_buffer, len); | |
415 | stdin_bytes += len; | |
416 | /* If we have a pending EOF, send it now. */ | |
417 | if (stdin_eof && buffer_len(&stdin_buffer) == 0) { | |
418 | packet_start(SSH_CMSG_EOF); | |
419 | packet_send(); | |
420 | } | |
421 | } | |
422 | } | |
423 | ||
424 | /* | |
425 | * Checks if the client window has changed, and sends a packet about it to | |
426 | * the server if so. The actual change is detected elsewhere (by a software | |
427 | * interrupt on Unix); this just checks the flag and sends a message if | |
428 | * appropriate. | |
429 | */ | |
430 | ||
431 | static void | |
432 | client_check_window_change(void) | |
433 | { | |
434 | struct winsize ws; | |
435 | ||
436 | if (! received_window_change_signal) | |
437 | return; | |
438 | /** XXX race */ | |
439 | received_window_change_signal = 0; | |
440 | ||
3c0ef626 | 441 | debug2("client_check_window_change: changed"); |
442 | ||
443 | if (compat20) { | |
c9f39d2c | 444 | channel_send_window_changes(); |
3c0ef626 | 445 | } else { |
c9f39d2c | 446 | if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0) |
447 | return; | |
3c0ef626 | 448 | packet_start(SSH_CMSG_WINDOW_SIZE); |
9108f8d9 | 449 | packet_put_int((u_int)ws.ws_row); |
450 | packet_put_int((u_int)ws.ws_col); | |
451 | packet_put_int((u_int)ws.ws_xpixel); | |
452 | packet_put_int((u_int)ws.ws_ypixel); | |
3c0ef626 | 453 | packet_send(); |
454 | } | |
455 | } | |
456 | ||
cdd66111 | 457 | static void |
458 | client_global_request_reply(int type, u_int32_t seq, void *ctxt) | |
459 | { | |
460 | server_alive_timeouts = 0; | |
461 | client_global_request_reply_fwd(type, seq, ctxt); | |
462 | } | |
463 | ||
464 | static void | |
465 | server_alive_check(void) | |
466 | { | |
ff7ec503 | 467 | if (++server_alive_timeouts > options.server_alive_count_max) { |
468 | logit("Timeout, server not responding."); | |
469 | cleanup_exit(255); | |
470 | } | |
cdd66111 | 471 | packet_start(SSH2_MSG_GLOBAL_REQUEST); |
472 | packet_put_cstring("keepalive@openssh.com"); | |
473 | packet_put_char(1); /* boolean: want reply */ | |
474 | packet_send(); | |
475 | } | |
476 | ||
3c0ef626 | 477 | /* |
478 | * Waits until the client can do something (some data becomes available on | |
479 | * one of the file descriptors). | |
480 | */ | |
3c0ef626 | 481 | static void |
482 | client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp, | |
c9f39d2c | 483 | int *maxfdp, u_int *nallocp, int rekeying) |
3c0ef626 | 484 | { |
cdd66111 | 485 | struct timeval tv, *tvp; |
486 | int ret; | |
487 | ||
3c0ef626 | 488 | /* Add any selections by the channel mechanism. */ |
489 | channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, rekeying); | |
490 | ||
491 | if (!compat20) { | |
492 | /* Read from the connection, unless our buffers are full. */ | |
493 | if (buffer_len(&stdout_buffer) < buffer_high && | |
494 | buffer_len(&stderr_buffer) < buffer_high && | |
495 | channel_not_very_much_buffered_data()) | |
496 | FD_SET(connection_in, *readsetp); | |
497 | /* | |
498 | * Read from stdin, unless we have seen EOF or have very much | |
499 | * buffered data to send to the server. | |
500 | */ | |
501 | if (!stdin_eof && packet_not_very_much_data_to_write()) | |
502 | FD_SET(fileno(stdin), *readsetp); | |
503 | ||
504 | /* Select stdout/stderr if have data in buffer. */ | |
505 | if (buffer_len(&stdout_buffer) > 0) | |
506 | FD_SET(fileno(stdout), *writesetp); | |
507 | if (buffer_len(&stderr_buffer) > 0) | |
508 | FD_SET(fileno(stderr), *writesetp); | |
509 | } else { | |
510 | /* channel_prepare_select could have closed the last channel */ | |
511 | if (session_closed && !channel_still_open() && | |
512 | !packet_have_data_to_write()) { | |
513 | /* clear mask since we did not call select() */ | |
514 | memset(*readsetp, 0, *nallocp); | |
515 | memset(*writesetp, 0, *nallocp); | |
516 | return; | |
517 | } else { | |
518 | FD_SET(connection_in, *readsetp); | |
519 | } | |
520 | } | |
521 | ||
522 | /* Select server connection if have data to write to the server. */ | |
523 | if (packet_have_data_to_write()) | |
524 | FD_SET(connection_out, *writesetp); | |
525 | ||
c9f39d2c | 526 | if (control_fd != -1) |
527 | FD_SET(control_fd, *readsetp); | |
528 | ||
3c0ef626 | 529 | /* |
530 | * Wait for something to happen. This will suspend the process until | |
531 | * some selected descriptor can be read, written, or has some other | |
cdd66111 | 532 | * event pending. |
3c0ef626 | 533 | */ |
534 | ||
cdd66111 | 535 | if (options.server_alive_interval == 0 || !compat20) |
536 | tvp = NULL; | |
c9f39d2c | 537 | else { |
cdd66111 | 538 | tv.tv_sec = options.server_alive_interval; |
539 | tv.tv_usec = 0; | |
540 | tvp = &tv; | |
541 | } | |
542 | ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp); | |
543 | if (ret < 0) { | |
3c0ef626 | 544 | char buf[100]; |
545 | ||
546 | /* | |
547 | * We have to clear the select masks, because we return. | |
548 | * We have to return, because the mainloop checks for the flags | |
549 | * set by the signal handlers. | |
550 | */ | |
551 | memset(*readsetp, 0, *nallocp); | |
552 | memset(*writesetp, 0, *nallocp); | |
553 | ||
554 | if (errno == EINTR) | |
555 | return; | |
556 | /* Note: we might still have data in the buffers. */ | |
557 | snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno)); | |
558 | buffer_append(&stderr_buffer, buf, strlen(buf)); | |
559 | quit_pending = 1; | |
cdd66111 | 560 | } else if (ret == 0) |
561 | server_alive_check(); | |
3c0ef626 | 562 | } |
563 | ||
564 | static void | |
565 | client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr) | |
566 | { | |
3c0ef626 | 567 | /* Flush stdout and stderr buffers. */ |
568 | if (buffer_len(bout) > 0) | |
0fff78ff | 569 | atomicio(vwrite, fileno(stdout), buffer_ptr(bout), buffer_len(bout)); |
3c0ef626 | 570 | if (buffer_len(berr) > 0) |
0fff78ff | 571 | atomicio(vwrite, fileno(stderr), buffer_ptr(berr), buffer_len(berr)); |
3c0ef626 | 572 | |
573 | leave_raw_mode(); | |
574 | ||
575 | /* | |
576 | * Free (and clear) the buffer to reduce the amount of data that gets | |
577 | * written to swap. | |
578 | */ | |
579 | buffer_free(bin); | |
580 | buffer_free(bout); | |
581 | buffer_free(berr); | |
582 | ||
3c0ef626 | 583 | /* Send the suspend signal to the program itself. */ |
584 | kill(getpid(), SIGTSTP); | |
585 | ||
996d5e62 | 586 | /* Reset window sizes in case they have changed */ |
587 | received_window_change_signal = 1; | |
3c0ef626 | 588 | |
589 | /* OK, we have been continued by the user. Reinitialize buffers. */ | |
590 | buffer_init(bin); | |
591 | buffer_init(bout); | |
592 | buffer_init(berr); | |
593 | ||
594 | enter_raw_mode(); | |
595 | } | |
596 | ||
597 | static void | |
9108f8d9 | 598 | client_process_net_input(fd_set *readset) |
3c0ef626 | 599 | { |
600 | int len; | |
601 | char buf[8192]; | |
602 | ||
603 | /* | |
604 | * Read input from the server, and add any such data to the buffer of | |
605 | * the packet subsystem. | |
606 | */ | |
607 | if (FD_ISSET(connection_in, readset)) { | |
608 | /* Read as much as possible. */ | |
609 | len = read(connection_in, buf, sizeof(buf)); | |
610 | if (len == 0) { | |
611 | /* Received EOF. The remote host has closed the connection. */ | |
612 | snprintf(buf, sizeof buf, "Connection to %.300s closed by remote host.\r\n", | |
613 | host); | |
614 | buffer_append(&stderr_buffer, buf, strlen(buf)); | |
615 | quit_pending = 1; | |
616 | return; | |
617 | } | |
618 | /* | |
619 | * There is a kernel bug on Solaris that causes select to | |
620 | * sometimes wake up even though there is no data available. | |
621 | */ | |
622 | if (len < 0 && (errno == EAGAIN || errno == EINTR)) | |
623 | len = 0; | |
624 | ||
625 | if (len < 0) { | |
626 | /* An error has encountered. Perhaps there is a network problem. */ | |
627 | snprintf(buf, sizeof buf, "Read from remote host %.300s: %.100s\r\n", | |
628 | host, strerror(errno)); | |
629 | buffer_append(&stderr_buffer, buf, strlen(buf)); | |
630 | quit_pending = 1; | |
631 | return; | |
632 | } | |
633 | packet_process_incoming(buf, len); | |
634 | } | |
635 | } | |
636 | ||
c9f39d2c | 637 | static void |
638 | client_subsystem_reply(int type, u_int32_t seq, void *ctxt) | |
639 | { | |
640 | int id; | |
641 | Channel *c; | |
642 | ||
643 | id = packet_get_int(); | |
644 | packet_check_eom(); | |
645 | ||
646 | if ((c = channel_lookup(id)) == NULL) { | |
647 | error("%s: no channel for id %d", __func__, id); | |
648 | return; | |
649 | } | |
650 | ||
651 | if (type == SSH2_MSG_CHANNEL_SUCCESS) | |
652 | debug2("Request suceeded on channel %d", id); | |
653 | else if (type == SSH2_MSG_CHANNEL_FAILURE) { | |
654 | error("Request failed on channel %d", id); | |
655 | channel_free(c); | |
656 | } | |
657 | } | |
658 | ||
659 | static void | |
660 | client_extra_session2_setup(int id, void *arg) | |
661 | { | |
662 | struct confirm_ctx *cctx = arg; | |
665a873d | 663 | const char *display; |
c9f39d2c | 664 | Channel *c; |
665 | int i; | |
666 | ||
667 | if (cctx == NULL) | |
668 | fatal("%s: cctx == NULL", __func__); | |
669 | if ((c = channel_lookup(id)) == NULL) | |
670 | fatal("%s: no channel for id %d", __func__, id); | |
671 | ||
665a873d | 672 | display = getenv("DISPLAY"); |
673 | if (cctx->want_x_fwd && options.forward_x11 && display != NULL) { | |
674 | char *proto, *data; | |
675 | /* Get reasonable local authentication information. */ | |
676 | client_x11_get_proto(display, options.xauth_location, | |
677 | options.forward_x11_trusted, &proto, &data); | |
678 | /* Request forwarding with authentication spoofing. */ | |
679 | debug("Requesting X11 forwarding with authentication spoofing."); | |
680 | x11_request_forwarding_with_spoofing(id, display, proto, data); | |
681 | /* XXX wait for reply */ | |
682 | } | |
683 | ||
684 | if (cctx->want_agent_fwd && options.forward_agent) { | |
685 | debug("Requesting authentication agent forwarding."); | |
686 | channel_request_start(id, "auth-agent-req@openssh.com", 0); | |
687 | packet_send(); | |
688 | } | |
689 | ||
c9f39d2c | 690 | client_session2_setup(id, cctx->want_tty, cctx->want_subsys, |
691 | cctx->term, &cctx->tio, c->rfd, &cctx->cmd, cctx->env, | |
692 | client_subsystem_reply); | |
693 | ||
694 | c->confirm_ctx = NULL; | |
695 | buffer_free(&cctx->cmd); | |
696 | xfree(cctx->term); | |
697 | if (cctx->env != NULL) { | |
698 | for (i = 0; cctx->env[i] != NULL; i++) | |
699 | xfree(cctx->env[i]); | |
700 | xfree(cctx->env); | |
701 | } | |
702 | xfree(cctx); | |
703 | } | |
704 | ||
705 | static void | |
9108f8d9 | 706 | client_process_control(fd_set *readset) |
c9f39d2c | 707 | { |
708 | Buffer m; | |
709 | Channel *c; | |
799ae497 | 710 | int client_fd, new_fd[3], ver, allowed, window, packetmax; |
c9f39d2c | 711 | socklen_t addrlen; |
712 | struct sockaddr_storage addr; | |
713 | struct confirm_ctx *cctx; | |
714 | char *cmd; | |
665a873d | 715 | u_int i, len, env_len, command, flags; |
c9f39d2c | 716 | uid_t euid; |
717 | gid_t egid; | |
718 | ||
719 | /* | |
720 | * Accept connection on control socket | |
721 | */ | |
722 | if (control_fd == -1 || !FD_ISSET(control_fd, readset)) | |
723 | return; | |
724 | ||
725 | memset(&addr, 0, sizeof(addr)); | |
726 | addrlen = sizeof(addr); | |
727 | if ((client_fd = accept(control_fd, | |
728 | (struct sockaddr*)&addr, &addrlen)) == -1) { | |
729 | error("%s accept: %s", __func__, strerror(errno)); | |
730 | return; | |
731 | } | |
732 | ||
733 | if (getpeereid(client_fd, &euid, &egid) < 0) { | |
734 | error("%s getpeereid failed: %s", __func__, strerror(errno)); | |
735 | close(client_fd); | |
736 | return; | |
737 | } | |
738 | if ((euid != 0) && (getuid() != euid)) { | |
739 | error("control mode uid mismatch: peer euid %u != uid %u", | |
740 | (u_int) euid, (u_int) getuid()); | |
741 | close(client_fd); | |
742 | return; | |
743 | } | |
744 | ||
c9f39d2c | 745 | unset_nonblock(client_fd); |
746 | ||
996d5e62 | 747 | /* Read command */ |
c9f39d2c | 748 | buffer_init(&m); |
996d5e62 | 749 | if (ssh_msg_recv(client_fd, &m) == -1) { |
750 | error("%s: client msg_recv failed", __func__); | |
751 | close(client_fd); | |
752 | buffer_free(&m); | |
753 | return; | |
754 | } | |
665a873d | 755 | if ((ver = buffer_get_char(&m)) != SSHMUX_VER) { |
996d5e62 | 756 | error("%s: wrong client version %d", __func__, ver); |
757 | buffer_free(&m); | |
758 | close(client_fd); | |
759 | return; | |
760 | } | |
761 | ||
762 | allowed = 1; | |
763 | command = buffer_get_int(&m); | |
764 | flags = buffer_get_int(&m); | |
765 | ||
766 | buffer_clear(&m); | |
c9f39d2c | 767 | |
996d5e62 | 768 | switch (command) { |
769 | case SSHMUX_COMMAND_OPEN: | |
665a873d | 770 | if (options.control_master == SSHCTL_MASTER_ASK || |
771 | options.control_master == SSHCTL_MASTER_AUTO_ASK) | |
996d5e62 | 772 | allowed = ask_permission("Allow shared connection " |
773 | "to %s? ", host); | |
774 | /* continue below */ | |
775 | break; | |
776 | case SSHMUX_COMMAND_TERMINATE: | |
665a873d | 777 | if (options.control_master == SSHCTL_MASTER_ASK || |
778 | options.control_master == SSHCTL_MASTER_AUTO_ASK) | |
996d5e62 | 779 | allowed = ask_permission("Terminate shared connection " |
780 | "to %s? ", host); | |
781 | if (allowed) | |
782 | quit_pending = 1; | |
dec6d9fe | 783 | /* FALLTHROUGH */ |
996d5e62 | 784 | case SSHMUX_COMMAND_ALIVE_CHECK: |
785 | /* Reply for SSHMUX_COMMAND_TERMINATE and ALIVE_CHECK */ | |
786 | buffer_clear(&m); | |
787 | buffer_put_int(&m, allowed); | |
788 | buffer_put_int(&m, getpid()); | |
665a873d | 789 | if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) { |
996d5e62 | 790 | error("%s: client msg_send failed", __func__); |
791 | close(client_fd); | |
792 | buffer_free(&m); | |
793 | return; | |
794 | } | |
795 | buffer_free(&m); | |
796 | close(client_fd); | |
797 | return; | |
798 | default: | |
799 | error("Unsupported command %d", command); | |
800 | buffer_free(&m); | |
801 | close(client_fd); | |
802 | return; | |
803 | } | |
804 | ||
805 | /* Reply for SSHMUX_COMMAND_OPEN */ | |
806 | buffer_clear(&m); | |
c9f39d2c | 807 | buffer_put_int(&m, allowed); |
808 | buffer_put_int(&m, getpid()); | |
665a873d | 809 | if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) { |
c9f39d2c | 810 | error("%s: client msg_send failed", __func__); |
811 | close(client_fd); | |
812 | buffer_free(&m); | |
813 | return; | |
814 | } | |
c9f39d2c | 815 | |
816 | if (!allowed) { | |
817 | error("Refused control connection"); | |
818 | close(client_fd); | |
819 | buffer_free(&m); | |
820 | return; | |
821 | } | |
822 | ||
996d5e62 | 823 | buffer_clear(&m); |
c9f39d2c | 824 | if (ssh_msg_recv(client_fd, &m) == -1) { |
825 | error("%s: client msg_recv failed", __func__); | |
826 | close(client_fd); | |
827 | buffer_free(&m); | |
828 | return; | |
829 | } | |
665a873d | 830 | if ((ver = buffer_get_char(&m)) != SSHMUX_VER) { |
c9f39d2c | 831 | error("%s: wrong client version %d", __func__, ver); |
832 | buffer_free(&m); | |
833 | close(client_fd); | |
834 | return; | |
835 | } | |
836 | ||
9108f8d9 | 837 | cctx = xcalloc(1, sizeof(*cctx)); |
996d5e62 | 838 | cctx->want_tty = (flags & SSHMUX_FLAG_TTY) != 0; |
839 | cctx->want_subsys = (flags & SSHMUX_FLAG_SUBSYS) != 0; | |
665a873d | 840 | cctx->want_x_fwd = (flags & SSHMUX_FLAG_X11_FWD) != 0; |
841 | cctx->want_agent_fwd = (flags & SSHMUX_FLAG_AGENT_FWD) != 0; | |
c9f39d2c | 842 | cctx->term = buffer_get_string(&m, &len); |
843 | ||
844 | cmd = buffer_get_string(&m, &len); | |
845 | buffer_init(&cctx->cmd); | |
846 | buffer_append(&cctx->cmd, cmd, strlen(cmd)); | |
847 | ||
848 | env_len = buffer_get_int(&m); | |
849 | env_len = MIN(env_len, 4096); | |
850 | debug3("%s: receiving %d env vars", __func__, env_len); | |
851 | if (env_len != 0) { | |
9108f8d9 | 852 | cctx->env = xcalloc(env_len + 1, sizeof(*cctx->env)); |
c9f39d2c | 853 | for (i = 0; i < env_len; i++) |
854 | cctx->env[i] = buffer_get_string(&m, &len); | |
855 | cctx->env[i] = NULL; | |
856 | } | |
857 | ||
858 | debug2("%s: accepted tty %d, subsys %d, cmd %s", __func__, | |
859 | cctx->want_tty, cctx->want_subsys, cmd); | |
9108f8d9 | 860 | xfree(cmd); |
c9f39d2c | 861 | |
862 | /* Gather fds from client */ | |
863 | new_fd[0] = mm_receive_fd(client_fd); | |
864 | new_fd[1] = mm_receive_fd(client_fd); | |
865 | new_fd[2] = mm_receive_fd(client_fd); | |
866 | ||
867 | debug2("%s: got fds stdin %d, stdout %d, stderr %d", __func__, | |
868 | new_fd[0], new_fd[1], new_fd[2]); | |
869 | ||
870 | /* Try to pick up ttymodes from client before it goes raw */ | |
871 | if (cctx->want_tty && tcgetattr(new_fd[0], &cctx->tio) == -1) | |
872 | error("%s: tcgetattr: %s", __func__, strerror(errno)); | |
873 | ||
996d5e62 | 874 | /* This roundtrip is just for synchronisation of ttymodes */ |
c9f39d2c | 875 | buffer_clear(&m); |
665a873d | 876 | if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) { |
c9f39d2c | 877 | error("%s: client msg_send failed", __func__); |
878 | close(client_fd); | |
879 | close(new_fd[0]); | |
880 | close(new_fd[1]); | |
881 | close(new_fd[2]); | |
882 | buffer_free(&m); | |
996d5e62 | 883 | xfree(cctx->term); |
884 | if (env_len != 0) { | |
885 | for (i = 0; i < env_len; i++) | |
886 | xfree(cctx->env[i]); | |
887 | xfree(cctx->env); | |
888 | } | |
c9f39d2c | 889 | return; |
890 | } | |
891 | buffer_free(&m); | |
892 | ||
893 | /* enable nonblocking unless tty */ | |
894 | if (!isatty(new_fd[0])) | |
895 | set_nonblock(new_fd[0]); | |
896 | if (!isatty(new_fd[1])) | |
897 | set_nonblock(new_fd[1]); | |
898 | if (!isatty(new_fd[2])) | |
899 | set_nonblock(new_fd[2]); | |
900 | ||
901 | set_nonblock(client_fd); | |
902 | ||
799ae497 | 903 | window = CHAN_SES_WINDOW_DEFAULT; |
904 | packetmax = CHAN_SES_PACKET_DEFAULT; | |
905 | if (cctx->want_tty) { | |
906 | window >>= 1; | |
907 | packetmax >>= 1; | |
908 | } | |
909 | ||
c9f39d2c | 910 | c = channel_new("session", SSH_CHANNEL_OPENING, |
799ae497 | 911 | new_fd[0], new_fd[1], new_fd[2], window, packetmax, |
c9f39d2c | 912 | CHAN_EXTENDED_WRITE, "client-session", /*nonblock*/0); |
913 | ||
914 | /* XXX */ | |
915 | c->ctl_fd = client_fd; | |
916 | ||
917 | debug3("%s: channel_new: %d", __func__, c->self); | |
918 | ||
919 | channel_send_open(c->self); | |
920 | channel_register_confirm(c->self, client_extra_session2_setup, cctx); | |
921 | } | |
922 | ||
700318f3 | 923 | static void |
924 | process_cmdline(void) | |
925 | { | |
926 | void (*handler)(int); | |
996d5e62 | 927 | char *s, *cmd, *cancel_host; |
c9f39d2c | 928 | int delete = 0; |
700318f3 | 929 | int local = 0; |
996d5e62 | 930 | u_short cancel_port; |
931 | Forward fwd; | |
700318f3 | 932 | |
933 | leave_raw_mode(); | |
f5799ae1 | 934 | handler = signal(SIGINT, SIG_IGN); |
700318f3 | 935 | cmd = s = read_passphrase("\r\nssh> ", RP_ECHO); |
936 | if (s == NULL) | |
937 | goto out; | |
938 | while (*s && isspace(*s)) | |
939 | s++; | |
c9f39d2c | 940 | if (*s == '-') |
941 | s++; /* Skip cmdline '-', if any */ | |
942 | if (*s == '\0') | |
943 | goto out; | |
944 | ||
945 | if (*s == 'h' || *s == 'H' || *s == '?') { | |
946 | logit("Commands:"); | |
9108f8d9 | 947 | logit(" -L[bind_address:]port:host:hostport " |
948 | "Request local forward"); | |
949 | logit(" -R[bind_address:]port:host:hostport " | |
950 | "Request remote forward"); | |
951 | logit(" -KR[bind_address:]port " | |
952 | "Cancel remote forward"); | |
2c06c99b | 953 | if (!options.permit_local_command) |
954 | goto out; | |
9108f8d9 | 955 | logit(" !args " |
956 | "Execute local command"); | |
2c06c99b | 957 | goto out; |
958 | } | |
959 | ||
960 | if (*s == '!' && options.permit_local_command) { | |
961 | s++; | |
962 | ssh_local_cmd(s); | |
700318f3 | 963 | goto out; |
c9f39d2c | 964 | } |
965 | ||
966 | if (*s == 'K') { | |
967 | delete = 1; | |
968 | s++; | |
969 | } | |
970 | if (*s != 'L' && *s != 'R') { | |
0fff78ff | 971 | logit("Invalid command."); |
700318f3 | 972 | goto out; |
973 | } | |
c9f39d2c | 974 | if (*s == 'L') |
700318f3 | 975 | local = 1; |
c9f39d2c | 976 | if (local && delete) { |
977 | logit("Not supported."); | |
978 | goto out; | |
979 | } | |
980 | if ((!local || delete) && !compat20) { | |
0fff78ff | 981 | logit("Not supported for SSH protocol version 1."); |
700318f3 | 982 | goto out; |
983 | } | |
c9f39d2c | 984 | |
985 | s++; | |
700318f3 | 986 | while (*s && isspace(*s)) |
987 | s++; | |
988 | ||
c9f39d2c | 989 | if (delete) { |
996d5e62 | 990 | cancel_port = 0; |
991 | cancel_host = hpdelim(&s); /* may be NULL */ | |
992 | if (s != NULL) { | |
993 | cancel_port = a2port(s); | |
994 | cancel_host = cleanhostname(cancel_host); | |
995 | } else { | |
996 | cancel_port = a2port(cancel_host); | |
997 | cancel_host = NULL; | |
c9f39d2c | 998 | } |
996d5e62 | 999 | if (cancel_port == 0) { |
1000 | logit("Bad forwarding close port"); | |
c9f39d2c | 1001 | goto out; |
1002 | } | |
996d5e62 | 1003 | channel_request_rforward_cancel(cancel_host, cancel_port); |
c9f39d2c | 1004 | } else { |
996d5e62 | 1005 | if (!parse_forward(&fwd, s)) { |
c9f39d2c | 1006 | logit("Bad forwarding specification."); |
1007 | goto out; | |
1008 | } | |
c9f39d2c | 1009 | if (local) { |
996d5e62 | 1010 | if (channel_setup_local_fwd_listener(fwd.listen_host, |
1011 | fwd.listen_port, fwd.connect_host, | |
1012 | fwd.connect_port, options.gateway_ports) < 0) { | |
c9f39d2c | 1013 | logit("Port forwarding failed."); |
1014 | goto out; | |
1015 | } | |
996d5e62 | 1016 | } else { |
9108f8d9 | 1017 | if (channel_request_remote_forwarding(fwd.listen_host, |
996d5e62 | 1018 | fwd.listen_port, fwd.connect_host, |
9108f8d9 | 1019 | fwd.connect_port) < 0) { |
1020 | logit("Port forwarding failed."); | |
1021 | goto out; | |
1022 | } | |
996d5e62 | 1023 | } |
1024 | ||
c9f39d2c | 1025 | logit("Forwarding port."); |
1026 | } | |
1027 | ||
700318f3 | 1028 | out: |
1029 | signal(SIGINT, handler); | |
1030 | enter_raw_mode(); | |
1031 | if (cmd) | |
1032 | xfree(cmd); | |
1033 | } | |
1034 | ||
3c0ef626 | 1035 | /* process the characters one by one */ |
1036 | static int | |
1037 | process_escapes(Buffer *bin, Buffer *bout, Buffer *berr, char *buf, int len) | |
1038 | { | |
1039 | char string[1024]; | |
1040 | pid_t pid; | |
1041 | int bytes = 0; | |
1042 | u_int i; | |
1043 | u_char ch; | |
1044 | char *s; | |
1045 | ||
665a873d | 1046 | if (len <= 0) |
1047 | return (0); | |
1048 | ||
1049 | for (i = 0; i < (u_int)len; i++) { | |
3c0ef626 | 1050 | /* Get one character at a time. */ |
1051 | ch = buf[i]; | |
1052 | ||
1053 | if (escape_pending) { | |
1054 | /* We have previously seen an escape character. */ | |
1055 | /* Clear the flag now. */ | |
1056 | escape_pending = 0; | |
1057 | ||
1058 | /* Process the escaped character. */ | |
1059 | switch (ch) { | |
1060 | case '.': | |
1061 | /* Terminate the connection. */ | |
1062 | snprintf(string, sizeof string, "%c.\r\n", escape_char); | |
1063 | buffer_append(berr, string, strlen(string)); | |
1064 | ||
1065 | quit_pending = 1; | |
1066 | return -1; | |
1067 | ||
1068 | case 'Z' - 64: | |
1069 | /* Suspend the program. */ | |
1070 | /* Print a message to that effect to the user. */ | |
1071 | snprintf(string, sizeof string, "%c^Z [suspend ssh]\r\n", escape_char); | |
1072 | buffer_append(berr, string, strlen(string)); | |
1073 | ||
1074 | /* Restore terminal modes and suspend. */ | |
1075 | client_suspend_self(bin, bout, berr); | |
1076 | ||
1077 | /* We have been continued. */ | |
1078 | continue; | |
1079 | ||
0fff78ff | 1080 | case 'B': |
1081 | if (compat20) { | |
1082 | snprintf(string, sizeof string, | |
1083 | "%cB\r\n", escape_char); | |
1084 | buffer_append(berr, string, | |
1085 | strlen(string)); | |
1086 | channel_request_start(session_ident, | |
1087 | "break", 0); | |
1088 | packet_put_int(1000); | |
1089 | packet_send(); | |
1090 | } | |
1091 | continue; | |
1092 | ||
3c0ef626 | 1093 | case 'R': |
1094 | if (compat20) { | |
1095 | if (datafellows & SSH_BUG_NOREKEY) | |
0fff78ff | 1096 | logit("Server does not support re-keying"); |
3c0ef626 | 1097 | else |
1098 | need_rekeying = 1; | |
1099 | } | |
1100 | continue; | |
1101 | ||
1102 | case '&': | |
1103 | /* | |
1104 | * Detach the program (continue to serve connections, | |
1105 | * but put in background and no more new connections). | |
1106 | */ | |
1107 | /* Restore tty modes. */ | |
1108 | leave_raw_mode(); | |
1109 | ||
1110 | /* Stop listening for new connections. */ | |
1111 | channel_stop_listening(); | |
1112 | ||
1113 | snprintf(string, sizeof string, | |
1114 | "%c& [backgrounded]\n", escape_char); | |
1115 | buffer_append(berr, string, strlen(string)); | |
1116 | ||
1117 | /* Fork into background. */ | |
1118 | pid = fork(); | |
1119 | if (pid < 0) { | |
1120 | error("fork: %.100s", strerror(errno)); | |
1121 | continue; | |
1122 | } | |
1123 | if (pid != 0) { /* This is the parent. */ | |
1124 | /* The parent just exits. */ | |
1125 | exit(0); | |
1126 | } | |
1127 | /* The child continues serving connections. */ | |
1128 | if (compat20) { | |
1129 | buffer_append(bin, "\004", 1); | |
1130 | /* fake EOF on stdin */ | |
1131 | return -1; | |
1132 | } else if (!stdin_eof) { | |
1133 | /* | |
1134 | * Sending SSH_CMSG_EOF alone does not always appear | |
1135 | * to be enough. So we try to send an EOF character | |
1136 | * first. | |
1137 | */ | |
1138 | packet_start(SSH_CMSG_STDIN_DATA); | |
1139 | packet_put_string("\004", 1); | |
1140 | packet_send(); | |
1141 | /* Close stdin. */ | |
1142 | stdin_eof = 1; | |
1143 | if (buffer_len(bin) == 0) { | |
1144 | packet_start(SSH_CMSG_EOF); | |
1145 | packet_send(); | |
1146 | } | |
1147 | } | |
1148 | continue; | |
1149 | ||
1150 | case '?': | |
1151 | snprintf(string, sizeof string, | |
1152 | "%c?\r\n\ | |
1153 | Supported escape sequences:\r\n\ | |
41b2f314 | 1154 | %c. - terminate connection\r\n\ |
0fff78ff | 1155 | %cB - send a BREAK to the remote system\r\n\ |
41b2f314 | 1156 | %cC - open a command line\r\n\ |
1157 | %cR - Request rekey (SSH protocol 2 only)\r\n\ | |
1158 | %c^Z - suspend ssh\r\n\ | |
1159 | %c# - list forwarded connections\r\n\ | |
1160 | %c& - background ssh (when waiting for connections to terminate)\r\n\ | |
1161 | %c? - this message\r\n\ | |
1162 | %c%c - send the escape character by typing it twice\r\n\ | |
3c0ef626 | 1163 | (Note that escapes are only recognized immediately after newline.)\r\n", |
41b2f314 | 1164 | escape_char, escape_char, escape_char, escape_char, |
1165 | escape_char, escape_char, escape_char, escape_char, | |
0fff78ff | 1166 | escape_char, escape_char, escape_char); |
3c0ef626 | 1167 | buffer_append(berr, string, strlen(string)); |
1168 | continue; | |
1169 | ||
1170 | case '#': | |
1171 | snprintf(string, sizeof string, "%c#\r\n", escape_char); | |
1172 | buffer_append(berr, string, strlen(string)); | |
1173 | s = channel_open_message(); | |
1174 | buffer_append(berr, s, strlen(s)); | |
1175 | xfree(s); | |
1176 | continue; | |
1177 | ||
700318f3 | 1178 | case 'C': |
1179 | process_cmdline(); | |
1180 | continue; | |
1181 | ||
3c0ef626 | 1182 | default: |
1183 | if (ch != escape_char) { | |
1184 | buffer_put_char(bin, escape_char); | |
1185 | bytes++; | |
1186 | } | |
1187 | /* Escaped characters fall through here */ | |
1188 | break; | |
1189 | } | |
1190 | } else { | |
1191 | /* | |
1192 | * The previous character was not an escape char. Check if this | |
1193 | * is an escape. | |
1194 | */ | |
1195 | if (last_was_cr && ch == escape_char) { | |
1196 | /* It is. Set the flag and continue to next character. */ | |
1197 | escape_pending = 1; | |
1198 | continue; | |
1199 | } | |
1200 | } | |
1201 | ||
1202 | /* | |
1203 | * Normal character. Record whether it was a newline, | |
1204 | * and append it to the buffer. | |
1205 | */ | |
1206 | last_was_cr = (ch == '\r' || ch == '\n'); | |
1207 | buffer_put_char(bin, ch); | |
1208 | bytes++; | |
1209 | } | |
1210 | return bytes; | |
1211 | } | |
1212 | ||
1213 | static void | |
9108f8d9 | 1214 | client_process_input(fd_set *readset) |
3c0ef626 | 1215 | { |
1216 | int len; | |
1217 | char buf[8192]; | |
1218 | ||
1219 | /* Read input from stdin. */ | |
1220 | if (FD_ISSET(fileno(stdin), readset)) { | |
1221 | /* Read as much as possible. */ | |
1222 | len = read(fileno(stdin), buf, sizeof(buf)); | |
1223 | if (len < 0 && (errno == EAGAIN || errno == EINTR)) | |
1224 | return; /* we'll try again later */ | |
1225 | if (len <= 0) { | |
1226 | /* | |
1227 | * Received EOF or error. They are treated | |
1228 | * similarly, except that an error message is printed | |
1229 | * if it was an error condition. | |
1230 | */ | |
1231 | if (len < 0) { | |
1232 | snprintf(buf, sizeof buf, "read: %.100s\r\n", strerror(errno)); | |
1233 | buffer_append(&stderr_buffer, buf, strlen(buf)); | |
1234 | } | |
1235 | /* Mark that we have seen EOF. */ | |
1236 | stdin_eof = 1; | |
1237 | /* | |
1238 | * Send an EOF message to the server unless there is | |
1239 | * data in the buffer. If there is data in the | |
1240 | * buffer, no message will be sent now. Code | |
1241 | * elsewhere will send the EOF when the buffer | |
1242 | * becomes empty if stdin_eof is set. | |
1243 | */ | |
1244 | if (buffer_len(&stdin_buffer) == 0) { | |
1245 | packet_start(SSH_CMSG_EOF); | |
1246 | packet_send(); | |
1247 | } | |
1248 | } else if (escape_char == SSH_ESCAPECHAR_NONE) { | |
1249 | /* | |
1250 | * Normal successful read, and no escape character. | |
1251 | * Just append the data to buffer. | |
1252 | */ | |
1253 | buffer_append(&stdin_buffer, buf, len); | |
1254 | } else { | |
1255 | /* | |
1256 | * Normal, successful read. But we have an escape character | |
1257 | * and have to process the characters one by one. | |
1258 | */ | |
1259 | if (process_escapes(&stdin_buffer, &stdout_buffer, | |
1260 | &stderr_buffer, buf, len) == -1) | |
1261 | return; | |
1262 | } | |
1263 | } | |
1264 | } | |
1265 | ||
1266 | static void | |
9108f8d9 | 1267 | client_process_output(fd_set *writeset) |
3c0ef626 | 1268 | { |
1269 | int len; | |
1270 | char buf[100]; | |
1271 | ||
1272 | /* Write buffered output to stdout. */ | |
1273 | if (FD_ISSET(fileno(stdout), writeset)) { | |
1274 | /* Write as much data as possible. */ | |
1275 | len = write(fileno(stdout), buffer_ptr(&stdout_buffer), | |
1276 | buffer_len(&stdout_buffer)); | |
1277 | if (len <= 0) { | |
1278 | if (errno == EINTR || errno == EAGAIN) | |
1279 | len = 0; | |
1280 | else { | |
1281 | /* | |
1282 | * An error or EOF was encountered. Put an | |
1283 | * error message to stderr buffer. | |
1284 | */ | |
1285 | snprintf(buf, sizeof buf, "write stdout: %.50s\r\n", strerror(errno)); | |
1286 | buffer_append(&stderr_buffer, buf, strlen(buf)); | |
1287 | quit_pending = 1; | |
1288 | return; | |
1289 | } | |
1290 | } | |
1291 | /* Consume printed data from the buffer. */ | |
1292 | buffer_consume(&stdout_buffer, len); | |
1293 | stdout_bytes += len; | |
1294 | } | |
1295 | /* Write buffered output to stderr. */ | |
1296 | if (FD_ISSET(fileno(stderr), writeset)) { | |
1297 | /* Write as much data as possible. */ | |
1298 | len = write(fileno(stderr), buffer_ptr(&stderr_buffer), | |
1299 | buffer_len(&stderr_buffer)); | |
1300 | if (len <= 0) { | |
1301 | if (errno == EINTR || errno == EAGAIN) | |
1302 | len = 0; | |
1303 | else { | |
1304 | /* EOF or error, but can't even print error message. */ | |
1305 | quit_pending = 1; | |
1306 | return; | |
1307 | } | |
1308 | } | |
1309 | /* Consume printed characters from the buffer. */ | |
1310 | buffer_consume(&stderr_buffer, len); | |
1311 | stderr_bytes += len; | |
1312 | } | |
1313 | } | |
1314 | ||
1315 | /* | |
1316 | * Get packets from the connection input buffer, and process them as long as | |
1317 | * there are packets available. | |
1318 | * | |
1319 | * Any unknown packets received during the actual | |
1320 | * session cause the session to terminate. This is | |
1321 | * intended to make debugging easier since no | |
1322 | * confirmations are sent. Any compatible protocol | |
1323 | * extensions must be negotiated during the | |
1324 | * preparatory phase. | |
1325 | */ | |
1326 | ||
1327 | static void | |
1328 | client_process_buffered_input_packets(void) | |
1329 | { | |
1330 | dispatch_run(DISPATCH_NONBLOCK, &quit_pending, compat20 ? xxx_kex : NULL); | |
1331 | } | |
1332 | ||
1333 | /* scan buf[] for '~' before sending data to the peer */ | |
1334 | ||
1335 | static int | |
1336 | simple_escape_filter(Channel *c, char *buf, int len) | |
1337 | { | |
1338 | /* XXX we assume c->extended is writeable */ | |
1339 | return process_escapes(&c->input, &c->output, &c->extended, buf, len); | |
1340 | } | |
1341 | ||
1342 | static void | |
1343 | client_channel_closed(int id, void *arg) | |
1344 | { | |
3c0ef626 | 1345 | channel_cancel_cleanup(id); |
1346 | session_closed = 1; | |
cdd66111 | 1347 | leave_raw_mode(); |
3c0ef626 | 1348 | } |
1349 | ||
1350 | /* | |
1351 | * Implements the interactive session with the server. This is called after | |
1352 | * the user has been authenticated, and a command has been started on the | |
1353 | * remote host. If escape_char != SSH_ESCAPECHAR_NONE, it is the character | |
1354 | * used as an escape character for terminating or suspending the session. | |
1355 | */ | |
1356 | ||
1357 | int | |
1358 | client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id) | |
1359 | { | |
1360 | fd_set *readset = NULL, *writeset = NULL; | |
1361 | double start_time, total_time; | |
c9f39d2c | 1362 | int max_fd = 0, max_fd2 = 0, len, rekeying = 0; |
1363 | u_int nalloc = 0; | |
3c0ef626 | 1364 | char buf[100]; |
1365 | ||
1366 | debug("Entering interactive session."); | |
1367 | ||
1368 | start_time = get_current_time(); | |
1369 | ||
1370 | /* Initialize variables. */ | |
1371 | escape_pending = 0; | |
1372 | last_was_cr = 1; | |
1373 | exit_status = -1; | |
1374 | stdin_eof = 0; | |
1375 | buffer_high = 64 * 1024; | |
1376 | connection_in = packet_get_connection_in(); | |
1377 | connection_out = packet_get_connection_out(); | |
1378 | max_fd = MAX(connection_in, connection_out); | |
c9f39d2c | 1379 | if (control_fd != -1) |
1380 | max_fd = MAX(max_fd, control_fd); | |
3c0ef626 | 1381 | |
1382 | if (!compat20) { | |
1383 | /* enable nonblocking unless tty */ | |
1384 | if (!isatty(fileno(stdin))) | |
1385 | set_nonblock(fileno(stdin)); | |
1386 | if (!isatty(fileno(stdout))) | |
1387 | set_nonblock(fileno(stdout)); | |
1388 | if (!isatty(fileno(stderr))) | |
1389 | set_nonblock(fileno(stderr)); | |
1390 | max_fd = MAX(max_fd, fileno(stdin)); | |
1391 | max_fd = MAX(max_fd, fileno(stdout)); | |
1392 | max_fd = MAX(max_fd, fileno(stderr)); | |
1393 | } | |
1394 | stdin_bytes = 0; | |
1395 | stdout_bytes = 0; | |
1396 | stderr_bytes = 0; | |
1397 | quit_pending = 0; | |
1398 | escape_char = escape_char_arg; | |
1399 | ||
1400 | /* Initialize buffers. */ | |
1401 | buffer_init(&stdin_buffer); | |
1402 | buffer_init(&stdout_buffer); | |
1403 | buffer_init(&stderr_buffer); | |
1404 | ||
1405 | client_init_dispatch(); | |
1406 | ||
6a9b3198 | 1407 | /* |
1408 | * Set signal handlers, (e.g. to restore non-blocking mode) | |
1409 | * but don't overwrite SIG_IGN, matches behaviour from rsh(1) | |
1410 | */ | |
996d5e62 | 1411 | if (signal(SIGHUP, SIG_IGN) != SIG_IGN) |
1412 | signal(SIGHUP, signal_handler); | |
6a9b3198 | 1413 | if (signal(SIGINT, SIG_IGN) != SIG_IGN) |
1414 | signal(SIGINT, signal_handler); | |
1415 | if (signal(SIGQUIT, SIG_IGN) != SIG_IGN) | |
1416 | signal(SIGQUIT, signal_handler); | |
1417 | if (signal(SIGTERM, SIG_IGN) != SIG_IGN) | |
1418 | signal(SIGTERM, signal_handler); | |
996d5e62 | 1419 | signal(SIGWINCH, window_change_handler); |
3c0ef626 | 1420 | |
1421 | if (have_pty) | |
1422 | enter_raw_mode(); | |
1423 | ||
1424 | if (compat20) { | |
1425 | session_ident = ssh2_chan_id; | |
1426 | if (escape_char != SSH_ESCAPECHAR_NONE) | |
1427 | channel_register_filter(session_ident, | |
2c06c99b | 1428 | simple_escape_filter, NULL); |
3c0ef626 | 1429 | if (session_ident != -1) |
1430 | channel_register_cleanup(session_ident, | |
2c06c99b | 1431 | client_channel_closed, 0); |
3c0ef626 | 1432 | } else { |
1433 | /* Check if we should immediately send eof on stdin. */ | |
1434 | client_check_initial_eof_on_stdin(); | |
1435 | } | |
1436 | ||
1437 | /* Main loop of the client for the interactive session mode. */ | |
1438 | while (!quit_pending) { | |
1439 | ||
1440 | /* Process buffered packets sent by the server. */ | |
1441 | client_process_buffered_input_packets(); | |
1442 | ||
1443 | if (compat20 && session_closed && !channel_still_open()) | |
1444 | break; | |
1445 | ||
1446 | rekeying = (xxx_kex != NULL && !xxx_kex->done); | |
1447 | ||
1448 | if (rekeying) { | |
1449 | debug("rekeying in progress"); | |
1450 | } else { | |
1451 | /* | |
1452 | * Make packets of buffered stdin data, and buffer | |
1453 | * them for sending to the server. | |
1454 | */ | |
1455 | if (!compat20) | |
1456 | client_make_packets_from_stdin_data(); | |
1457 | ||
1458 | /* | |
1459 | * Make packets from buffered channel data, and | |
1460 | * enqueue them for sending to the server. | |
1461 | */ | |
1462 | if (packet_not_very_much_data_to_write()) | |
1463 | channel_output_poll(); | |
1464 | ||
1465 | /* | |
1466 | * Check if the window size has changed, and buffer a | |
1467 | * message about it to the server if so. | |
1468 | */ | |
1469 | client_check_window_change(); | |
1470 | ||
1471 | if (quit_pending) | |
1472 | break; | |
1473 | } | |
1474 | /* | |
1475 | * Wait until we have something to do (something becomes | |
1476 | * available on one of the descriptors). | |
1477 | */ | |
1478 | max_fd2 = max_fd; | |
1479 | client_wait_until_can_do_something(&readset, &writeset, | |
1480 | &max_fd2, &nalloc, rekeying); | |
1481 | ||
1482 | if (quit_pending) | |
1483 | break; | |
1484 | ||
1485 | /* Do channel operations unless rekeying in progress. */ | |
1486 | if (!rekeying) { | |
1487 | channel_after_select(readset, writeset); | |
0fff78ff | 1488 | if (need_rekeying || packet_need_rekeying()) { |
1489 | debug("need rekeying"); | |
3c0ef626 | 1490 | xxx_kex->done = 0; |
1491 | kex_send_kexinit(xxx_kex); | |
1492 | need_rekeying = 0; | |
1493 | } | |
1494 | } | |
1495 | ||
1496 | /* Buffer input from the connection. */ | |
1497 | client_process_net_input(readset); | |
1498 | ||
c9f39d2c | 1499 | /* Accept control connections. */ |
1500 | client_process_control(readset); | |
1501 | ||
3c0ef626 | 1502 | if (quit_pending) |
1503 | break; | |
1504 | ||
1505 | if (!compat20) { | |
1506 | /* Buffer data from stdin */ | |
1507 | client_process_input(readset); | |
1508 | /* | |
1509 | * Process output to stdout and stderr. Output to | |
1510 | * the connection is processed elsewhere (above). | |
1511 | */ | |
1512 | client_process_output(writeset); | |
1513 | } | |
1514 | ||
1515 | /* Send as much buffered packet data as possible to the sender. */ | |
1516 | if (FD_ISSET(connection_out, writeset)) | |
1517 | packet_write_poll(); | |
1518 | } | |
1519 | if (readset) | |
1520 | xfree(readset); | |
1521 | if (writeset) | |
1522 | xfree(writeset); | |
1523 | ||
1524 | /* Terminate the session. */ | |
1525 | ||
1526 | /* Stop watching for window change. */ | |
996d5e62 | 1527 | signal(SIGWINCH, SIG_DFL); |
3c0ef626 | 1528 | |
1529 | channel_free_all(); | |
1530 | ||
1531 | if (have_pty) | |
1532 | leave_raw_mode(); | |
1533 | ||
1534 | /* restore blocking io */ | |
1535 | if (!isatty(fileno(stdin))) | |
1536 | unset_nonblock(fileno(stdin)); | |
1537 | if (!isatty(fileno(stdout))) | |
1538 | unset_nonblock(fileno(stdout)); | |
1539 | if (!isatty(fileno(stderr))) | |
1540 | unset_nonblock(fileno(stderr)); | |
1541 | ||
cdd66111 | 1542 | /* |
1543 | * If there was no shell or command requested, there will be no remote | |
1544 | * exit status to be returned. In that case, clear error code if the | |
1545 | * connection was deliberately terminated at this end. | |
1546 | */ | |
1547 | if (no_shell_flag && received_signal == SIGTERM) { | |
1548 | received_signal = 0; | |
1549 | exit_status = 0; | |
9cb1827b | 1550 | } |
12408a1b | 1551 | |
cdd66111 | 1552 | if (received_signal) |
1553 | fatal("Killed by signal %d.", (int) received_signal); | |
1554 | ||
3c0ef626 | 1555 | /* |
1556 | * In interactive mode (with pseudo tty) display a message indicating | |
1557 | * that the connection has been closed. | |
1558 | */ | |
1559 | if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) { | |
1560 | snprintf(buf, sizeof buf, "Connection to %.64s closed.\r\n", host); | |
1561 | buffer_append(&stderr_buffer, buf, strlen(buf)); | |
1562 | } | |
1563 | ||
1564 | /* Output any buffered data for stdout. */ | |
1565 | while (buffer_len(&stdout_buffer) > 0) { | |
1566 | len = write(fileno(stdout), buffer_ptr(&stdout_buffer), | |
1567 | buffer_len(&stdout_buffer)); | |
1568 | if (len <= 0) { | |
1569 | error("Write failed flushing stdout buffer."); | |
1570 | break; | |
1571 | } | |
1572 | buffer_consume(&stdout_buffer, len); | |
1573 | stdout_bytes += len; | |
1574 | } | |
1575 | ||
1576 | /* Output any buffered data for stderr. */ | |
1577 | while (buffer_len(&stderr_buffer) > 0) { | |
1578 | len = write(fileno(stderr), buffer_ptr(&stderr_buffer), | |
1579 | buffer_len(&stderr_buffer)); | |
1580 | if (len <= 0) { | |
1581 | error("Write failed flushing stderr buffer."); | |
1582 | break; | |
1583 | } | |
1584 | buffer_consume(&stderr_buffer, len); | |
1585 | stderr_bytes += len; | |
1586 | } | |
1587 | ||
1588 | /* Clear and free any buffers. */ | |
1589 | memset(buf, 0, sizeof(buf)); | |
1590 | buffer_free(&stdin_buffer); | |
1591 | buffer_free(&stdout_buffer); | |
1592 | buffer_free(&stderr_buffer); | |
1593 | ||
1594 | /* Report bytes transferred, and transfer rates. */ | |
1595 | total_time = get_current_time() - start_time; | |
1596 | debug("Transferred: stdin %lu, stdout %lu, stderr %lu bytes in %.1f seconds", | |
e9a17296 | 1597 | stdin_bytes, stdout_bytes, stderr_bytes, total_time); |
3c0ef626 | 1598 | if (total_time > 0) |
1599 | debug("Bytes per second: stdin %.1f, stdout %.1f, stderr %.1f", | |
e9a17296 | 1600 | stdin_bytes / total_time, stdout_bytes / total_time, |
1601 | stderr_bytes / total_time); | |
3c0ef626 | 1602 | |
1603 | /* Return the exit status of the program. */ | |
1604 | debug("Exit status %d", exit_status); | |
1605 | return exit_status; | |
1606 | } | |
1607 | ||
1608 | /*********/ | |
1609 | ||
1610 | static void | |
e9a17296 | 1611 | client_input_stdout_data(int type, u_int32_t seq, void *ctxt) |
3c0ef626 | 1612 | { |
1613 | u_int data_len; | |
1614 | char *data = packet_get_string(&data_len); | |
e9a17296 | 1615 | packet_check_eom(); |
3c0ef626 | 1616 | buffer_append(&stdout_buffer, data, data_len); |
1617 | memset(data, 0, data_len); | |
1618 | xfree(data); | |
1619 | } | |
1620 | static void | |
e9a17296 | 1621 | client_input_stderr_data(int type, u_int32_t seq, void *ctxt) |
3c0ef626 | 1622 | { |
1623 | u_int data_len; | |
1624 | char *data = packet_get_string(&data_len); | |
e9a17296 | 1625 | packet_check_eom(); |
3c0ef626 | 1626 | buffer_append(&stderr_buffer, data, data_len); |
1627 | memset(data, 0, data_len); | |
1628 | xfree(data); | |
1629 | } | |
1630 | static void | |
e9a17296 | 1631 | client_input_exit_status(int type, u_int32_t seq, void *ctxt) |
3c0ef626 | 1632 | { |
3c0ef626 | 1633 | exit_status = packet_get_int(); |
e9a17296 | 1634 | packet_check_eom(); |
3c0ef626 | 1635 | /* Acknowledge the exit. */ |
1636 | packet_start(SSH_CMSG_EXIT_CONFIRMATION); | |
1637 | packet_send(); | |
1638 | /* | |
1639 | * Must wait for packet to be sent since we are | |
1640 | * exiting the loop. | |
1641 | */ | |
1642 | packet_write_wait(); | |
1643 | /* Flag that we want to exit. */ | |
1644 | quit_pending = 1; | |
1645 | } | |
cdd66111 | 1646 | static void |
1647 | client_input_agent_open(int type, u_int32_t seq, void *ctxt) | |
1648 | { | |
1649 | Channel *c = NULL; | |
1650 | int remote_id, sock; | |
1651 | ||
1652 | /* Read the remote channel number from the message. */ | |
1653 | remote_id = packet_get_int(); | |
1654 | packet_check_eom(); | |
1655 | ||
1656 | /* | |
1657 | * Get a connection to the local authentication agent (this may again | |
1658 | * get forwarded). | |
1659 | */ | |
1660 | sock = ssh_get_authentication_socket(); | |
1661 | ||
1662 | /* | |
1663 | * If we could not connect the agent, send an error message back to | |
1664 | * the server. This should never happen unless the agent dies, | |
1665 | * because authentication forwarding is only enabled if we have an | |
1666 | * agent. | |
1667 | */ | |
1668 | if (sock >= 0) { | |
1669 | c = channel_new("", SSH_CHANNEL_OPEN, sock, sock, | |
1670 | -1, 0, 0, 0, "authentication agent connection", 1); | |
1671 | c->remote_id = remote_id; | |
1672 | c->force_drain = 1; | |
1673 | } | |
1674 | if (c == NULL) { | |
1675 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
1676 | packet_put_int(remote_id); | |
1677 | } else { | |
1678 | /* Send a confirmation to the remote host. */ | |
1679 | debug("Forwarding authentication connection."); | |
1680 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1681 | packet_put_int(remote_id); | |
1682 | packet_put_int(c->self); | |
1683 | } | |
1684 | packet_send(); | |
1685 | } | |
3c0ef626 | 1686 | |
1687 | static Channel * | |
1688 | client_request_forwarded_tcpip(const char *request_type, int rchan) | |
1689 | { | |
41b2f314 | 1690 | Channel *c = NULL; |
3c0ef626 | 1691 | char *listen_address, *originator_address; |
1692 | int listen_port, originator_port; | |
1693 | int sock; | |
1694 | ||
1695 | /* Get rest of the packet */ | |
1696 | listen_address = packet_get_string(NULL); | |
1697 | listen_port = packet_get_int(); | |
1698 | originator_address = packet_get_string(NULL); | |
1699 | originator_port = packet_get_int(); | |
e9a17296 | 1700 | packet_check_eom(); |
3c0ef626 | 1701 | |
1702 | debug("client_request_forwarded_tcpip: listen %s port %d, originator %s port %d", | |
1703 | listen_address, listen_port, originator_address, originator_port); | |
1704 | ||
1705 | sock = channel_connect_by_listen_address(listen_port); | |
1706 | if (sock < 0) { | |
1707 | xfree(originator_address); | |
1708 | xfree(listen_address); | |
1709 | return NULL; | |
1710 | } | |
1711 | c = channel_new("forwarded-tcpip", | |
1712 | SSH_CHANNEL_CONNECTING, sock, sock, -1, | |
1713 | CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0, | |
0fff78ff | 1714 | originator_address, 1); |
3c0ef626 | 1715 | xfree(originator_address); |
1716 | xfree(listen_address); | |
1717 | return c; | |
1718 | } | |
1719 | ||
41b2f314 | 1720 | static Channel * |
3c0ef626 | 1721 | client_request_x11(const char *request_type, int rchan) |
1722 | { | |
1723 | Channel *c = NULL; | |
1724 | char *originator; | |
1725 | int originator_port; | |
1726 | int sock; | |
1727 | ||
1728 | if (!options.forward_x11) { | |
1729 | error("Warning: ssh server tried X11 forwarding."); | |
2c06c99b | 1730 | error("Warning: this is probably a break-in attempt by a malicious server."); |
3c0ef626 | 1731 | return NULL; |
1732 | } | |
1733 | originator = packet_get_string(NULL); | |
1734 | if (datafellows & SSH_BUG_X11FWD) { | |
1735 | debug2("buggy server: x11 request w/o originator_port"); | |
1736 | originator_port = 0; | |
1737 | } else { | |
1738 | originator_port = packet_get_int(); | |
1739 | } | |
e9a17296 | 1740 | packet_check_eom(); |
3c0ef626 | 1741 | /* XXX check permission */ |
1742 | debug("client_request_x11: request from %s %d", originator, | |
1743 | originator_port); | |
1744 | xfree(originator); | |
1745 | sock = x11_connect_display(); | |
1746 | if (sock < 0) | |
1747 | return NULL; | |
1748 | c = channel_new("x11", | |
1749 | SSH_CHANNEL_X11_OPEN, sock, sock, -1, | |
0fff78ff | 1750 | CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1); |
3c0ef626 | 1751 | c->force_drain = 1; |
1752 | return c; | |
1753 | } | |
1754 | ||
41b2f314 | 1755 | static Channel * |
3c0ef626 | 1756 | client_request_agent(const char *request_type, int rchan) |
1757 | { | |
1758 | Channel *c = NULL; | |
1759 | int sock; | |
1760 | ||
1761 | if (!options.forward_agent) { | |
1762 | error("Warning: ssh server tried agent forwarding."); | |
2c06c99b | 1763 | error("Warning: this is probably a break-in attempt by a malicious server."); |
3c0ef626 | 1764 | return NULL; |
1765 | } | |
799ae497 | 1766 | sock = ssh_get_authentication_socket(); |
3c0ef626 | 1767 | if (sock < 0) |
1768 | return NULL; | |
1769 | c = channel_new("authentication agent connection", | |
1770 | SSH_CHANNEL_OPEN, sock, sock, -1, | |
1771 | CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0, | |
0fff78ff | 1772 | "authentication agent connection", 1); |
3c0ef626 | 1773 | c->force_drain = 1; |
1774 | return c; | |
1775 | } | |
1776 | ||
1777 | /* XXXX move to generic input handler */ | |
1778 | static void | |
e9a17296 | 1779 | client_input_channel_open(int type, u_int32_t seq, void *ctxt) |
3c0ef626 | 1780 | { |
1781 | Channel *c = NULL; | |
1782 | char *ctype; | |
3c0ef626 | 1783 | int rchan; |
680cee3b | 1784 | u_int rmaxpack, rwindow, len; |
3c0ef626 | 1785 | |
1786 | ctype = packet_get_string(&len); | |
1787 | rchan = packet_get_int(); | |
1788 | rwindow = packet_get_int(); | |
1789 | rmaxpack = packet_get_int(); | |
1790 | ||
1791 | debug("client_input_channel_open: ctype %s rchan %d win %d max %d", | |
1792 | ctype, rchan, rwindow, rmaxpack); | |
1793 | ||
1794 | if (strcmp(ctype, "forwarded-tcpip") == 0) { | |
1795 | c = client_request_forwarded_tcpip(ctype, rchan); | |
1796 | } else if (strcmp(ctype, "x11") == 0) { | |
1797 | c = client_request_x11(ctype, rchan); | |
1798 | } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) { | |
1799 | c = client_request_agent(ctype, rchan); | |
1800 | } | |
1801 | /* XXX duplicate : */ | |
1802 | if (c != NULL) { | |
1803 | debug("confirm %s", ctype); | |
1804 | c->remote_id = rchan; | |
1805 | c->remote_window = rwindow; | |
1806 | c->remote_maxpacket = rmaxpack; | |
1807 | if (c->type != SSH_CHANNEL_CONNECTING) { | |
1808 | packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1809 | packet_put_int(c->remote_id); | |
1810 | packet_put_int(c->self); | |
1811 | packet_put_int(c->local_window); | |
1812 | packet_put_int(c->local_maxpacket); | |
1813 | packet_send(); | |
1814 | } | |
1815 | } else { | |
1816 | debug("failure %s", ctype); | |
1817 | packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE); | |
1818 | packet_put_int(rchan); | |
1819 | packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED); | |
1820 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { | |
1821 | packet_put_cstring("open failed"); | |
1822 | packet_put_cstring(""); | |
1823 | } | |
1824 | packet_send(); | |
1825 | } | |
1826 | xfree(ctype); | |
1827 | } | |
1828 | static void | |
e9a17296 | 1829 | client_input_channel_req(int type, u_int32_t seq, void *ctxt) |
3c0ef626 | 1830 | { |
1831 | Channel *c = NULL; | |
c9f39d2c | 1832 | int exitval, id, reply, success = 0; |
3c0ef626 | 1833 | char *rtype; |
1834 | ||
1835 | id = packet_get_int(); | |
1836 | rtype = packet_get_string(NULL); | |
1837 | reply = packet_get_char(); | |
1838 | ||
1839 | debug("client_input_channel_req: channel %d rtype %s reply %d", | |
1840 | id, rtype, reply); | |
1841 | ||
c9f39d2c | 1842 | if (id == -1) { |
1843 | error("client_input_channel_req: request for channel -1"); | |
1844 | } else if ((c = channel_lookup(id)) == NULL) { | |
3c0ef626 | 1845 | error("client_input_channel_req: channel %d: unknown channel", id); |
1846 | } else if (strcmp(rtype, "exit-status") == 0) { | |
c9f39d2c | 1847 | exitval = packet_get_int(); |
1848 | if (id == session_ident) { | |
1849 | success = 1; | |
1850 | exit_status = exitval; | |
1851 | } else if (c->ctl_fd == -1) { | |
1852 | error("client_input_channel_req: unexpected channel %d", | |
1853 | session_ident); | |
1854 | } else { | |
1855 | atomicio(vwrite, c->ctl_fd, &exitval, sizeof(exitval)); | |
1856 | success = 1; | |
1857 | } | |
e9a17296 | 1858 | packet_check_eom(); |
3c0ef626 | 1859 | } |
1860 | if (reply) { | |
1861 | packet_start(success ? | |
1862 | SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE); | |
c9f39d2c | 1863 | packet_put_int(id); |
3c0ef626 | 1864 | packet_send(); |
1865 | } | |
1866 | xfree(rtype); | |
1867 | } | |
e9a17296 | 1868 | static void |
1869 | client_input_global_request(int type, u_int32_t seq, void *ctxt) | |
1870 | { | |
1871 | char *rtype; | |
1872 | int want_reply; | |
1873 | int success = 0; | |
1874 | ||
1875 | rtype = packet_get_string(NULL); | |
1876 | want_reply = packet_get_char(); | |
cdd66111 | 1877 | debug("client_input_global_request: rtype %s want_reply %d", |
1878 | rtype, want_reply); | |
e9a17296 | 1879 | if (want_reply) { |
1880 | packet_start(success ? | |
1881 | SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE); | |
1882 | packet_send(); | |
1883 | packet_write_wait(); | |
1884 | } | |
1885 | xfree(rtype); | |
1886 | } | |
3c0ef626 | 1887 | |
c9f39d2c | 1888 | void |
1889 | client_session2_setup(int id, int want_tty, int want_subsystem, | |
1890 | const char *term, struct termios *tiop, int in_fd, Buffer *cmd, char **env, | |
1891 | dispatch_fn *subsys_repl) | |
1892 | { | |
1893 | int len; | |
996d5e62 | 1894 | Channel *c = NULL; |
c9f39d2c | 1895 | |
1896 | debug2("%s: id %d", __func__, id); | |
1897 | ||
996d5e62 | 1898 | if ((c = channel_lookup(id)) == NULL) |
1899 | fatal("client_session2_setup: channel %d: unknown channel", id); | |
1900 | ||
c9f39d2c | 1901 | if (want_tty) { |
1902 | struct winsize ws; | |
1903 | struct termios tio; | |
1904 | ||
1905 | /* Store window size in the packet. */ | |
1906 | if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0) | |
1907 | memset(&ws, 0, sizeof(ws)); | |
1908 | ||
1909 | channel_request_start(id, "pty-req", 0); | |
1910 | packet_put_cstring(term != NULL ? term : ""); | |
9108f8d9 | 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); | |
c9f39d2c | 1915 | tio = get_saved_tio(); |
1916 | tty_make_modes(-1, tiop != NULL ? tiop : &tio); | |
1917 | packet_send(); | |
1918 | /* XXX wait for reply */ | |
996d5e62 | 1919 | c->client_tty = 1; |
c9f39d2c | 1920 | } |
1921 | ||
1922 | /* Transfer any environment variables from client to server */ | |
1923 | if (options.num_send_env != 0 && env != NULL) { | |
1924 | int i, j, matched; | |
1925 | char *name, *val; | |
1926 | ||
1927 | debug("Sending environment."); | |
1928 | for (i = 0; env[i] != NULL; i++) { | |
1929 | /* Split */ | |
1930 | name = xstrdup(env[i]); | |
1931 | if ((val = strchr(name, '=')) == NULL) { | |
2c06c99b | 1932 | xfree(name); |
c9f39d2c | 1933 | continue; |
1934 | } | |
1935 | *val++ = '\0'; | |
1936 | ||
1937 | matched = 0; | |
1938 | for (j = 0; j < options.num_send_env; j++) { | |
1939 | if (match_pattern(name, options.send_env[j])) { | |
1940 | matched = 1; | |
1941 | break; | |
1942 | } | |
1943 | } | |
1944 | if (!matched) { | |
1945 | debug3("Ignored env %s", name); | |
2c06c99b | 1946 | xfree(name); |
c9f39d2c | 1947 | continue; |
1948 | } | |
1949 | ||
1950 | debug("Sending env %s = %s", name, val); | |
1951 | channel_request_start(id, "env", 0); | |
1952 | packet_put_cstring(name); | |
1953 | packet_put_cstring(val); | |
1954 | packet_send(); | |
2c06c99b | 1955 | xfree(name); |
c9f39d2c | 1956 | } |
1957 | } | |
1958 | ||
1959 | len = buffer_len(cmd); | |
1960 | if (len > 0) { | |
1961 | if (len > 900) | |
1962 | len = 900; | |
1963 | if (want_subsystem) { | |
1964 | debug("Sending subsystem: %.*s", len, (u_char*)buffer_ptr(cmd)); | |
1965 | channel_request_start(id, "subsystem", subsys_repl != NULL); | |
1966 | if (subsys_repl != NULL) { | |
1967 | /* register callback for reply */ | |
1968 | /* XXX we assume that client_loop has already been called */ | |
1969 | dispatch_set(SSH2_MSG_CHANNEL_FAILURE, subsys_repl); | |
1970 | dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, subsys_repl); | |
1971 | } | |
1972 | } else { | |
1973 | debug("Sending command: %.*s", len, (u_char*)buffer_ptr(cmd)); | |
1974 | channel_request_start(id, "exec", 0); | |
1975 | } | |
1976 | packet_put_string(buffer_ptr(cmd), buffer_len(cmd)); | |
1977 | packet_send(); | |
1978 | } else { | |
1979 | channel_request_start(id, "shell", 0); | |
1980 | packet_send(); | |
1981 | } | |
1982 | } | |
1983 | ||
3c0ef626 | 1984 | static void |
1985 | client_init_dispatch_20(void) | |
1986 | { | |
1987 | dispatch_init(&dispatch_protocol_error); | |
700318f3 | 1988 | |
3c0ef626 | 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); | |
e9a17296 | 1998 | dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request); |
3c0ef626 | 1999 | |
2000 | /* rekeying */ | |
2001 | dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit); | |
700318f3 | 2002 | |
2003 | /* global request reply messages */ | |
2004 | dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply); | |
2005 | dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply); | |
3c0ef626 | 2006 | } |
2007 | static void | |
2008 | client_init_dispatch_13(void) | |
2009 | { | |
2010 | dispatch_init(NULL); | |
2011 | dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close); | |
2012 | dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation); | |
2013 | dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data); | |
2014 | dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation); | |
2015 | dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure); | |
2016 | dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open); | |
2017 | dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status); | |
2018 | dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data); | |
2019 | dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data); | |
2020 | ||
2021 | dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ? | |
cdd66111 | 2022 | &client_input_agent_open : &deny_input_open); |
3c0ef626 | 2023 | dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ? |
2024 | &x11_input_open : &deny_input_open); | |
2025 | } | |
2026 | static void | |
2027 | client_init_dispatch_15(void) | |
2028 | { | |
2029 | client_init_dispatch_13(); | |
2030 | dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof); | |
2031 | dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose); | |
2032 | } | |
2033 | static void | |
2034 | client_init_dispatch(void) | |
2035 | { | |
2036 | if (compat20) | |
2037 | client_init_dispatch_20(); | |
2038 | else if (compat13) | |
2039 | client_init_dispatch_13(); | |
2040 | else | |
2041 | client_init_dispatch_15(); | |
2042 | } | |
cdd66111 | 2043 | |
2044 | /* client specific fatal cleanup */ | |
2045 | void | |
2046 | cleanup_exit(int i) | |
2047 | { | |
2048 | leave_raw_mode(); | |
2049 | leave_non_blocking(); | |
c9f39d2c | 2050 | if (options.control_path != NULL && control_fd != -1) |
2051 | unlink(options.control_path); | |
cdd66111 | 2052 | _exit(i); |
2053 | } |