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2e437378 | 1 | /* $OpenBSD: clientloop.c,v 1.176 2006/10/11 12:38:03 markus 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 | |
2e437378 | 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" |
2e437378 | 99 | #include "cipher.h" |
3c0ef626 | 100 | #include "kex.h" |
101 | #include "log.h" | |
102 | #include "readconf.h" | |
103 | #include "clientloop.h" | |
e00da40d | 104 | #include "sshconnect.h" |
3c0ef626 | 105 | #include "authfd.h" |
106 | #include "atomicio.h" | |
1b56ff3d | 107 | #include "sshpty.h" |
3c0ef626 | 108 | #include "misc.h" |
1b56ff3d | 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 | ||
416fd2a8 | 119 | /* Flag indicating that no shell has been requested */ |
120 | extern int no_shell_flag; | |
121 | ||
1b56ff3d | 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 | |
e00da40d | 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. */ | |
2e437378 | 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. */ | |
416fd2a8 | 160 | static int server_alive_timeouts = 0; |
3c0ef626 | 161 | |
162 | static void client_init_dispatch(void); | |
163 | int session_ident = -1; | |
164 | ||
1b56ff3d | 165 | struct confirm_ctx { |
166 | int want_tty; | |
167 | int want_subsys; | |
34fee935 | 168 | int want_x_fwd; |
169 | int want_agent_fwd; | |
1b56ff3d | 170 | Buffer cmd; |
171 | char *term; | |
172 | struct termios tio; | |
173 | char **env; | |
174 | }; | |
175 | ||
3c0ef626 | 176 | /*XXX*/ |
177 | extern Kex *xxx_kex; | |
178 | ||
1b56ff3d | 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) { | |
1b56ff3d | 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; | |
1b56ff3d | 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 | */ | |
2e437378 | 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 | */ | |
2e437378 | 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 | ||
34fee935 | 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), | |
e00da40d | 294 | "%s %s%s list %s 2>" _PATH_DEVNULL, |
34fee935 | 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) { | |
1b56ff3d | 444 | channel_send_window_changes(); |
3c0ef626 | 445 | } else { |
1b56ff3d | 446 | if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0) |
447 | return; | |
3c0ef626 | 448 | packet_start(SSH_CMSG_WINDOW_SIZE); |
2e437378 | 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 | ||
416fd2a8 | 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 | { | |
2e437378 | 467 | if (++server_alive_timeouts > options.server_alive_count_max) { |
468 | logit("Timeout, server not responding."); | |
469 | cleanup_exit(255); | |
470 | } | |
416fd2a8 | 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, | |
1b56ff3d | 483 | int *maxfdp, u_int *nallocp, int rekeying) |
3c0ef626 | 484 | { |
416fd2a8 | 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 | ||
1b56ff3d | 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 | |
416fd2a8 | 532 | * event pending. |
3c0ef626 | 533 | */ |
534 | ||
416fd2a8 | 535 | if (options.server_alive_interval == 0 || !compat20) |
536 | tvp = NULL; | |
1b56ff3d | 537 | else { |
416fd2a8 | 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; | |
416fd2a8 | 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) | |
70791e56 | 569 | atomicio(vwrite, fileno(stdout), buffer_ptr(bout), buffer_len(bout)); |
3c0ef626 | 570 | if (buffer_len(berr) > 0) |
70791e56 | 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 | ||
34fee935 | 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 | |
2e437378 | 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 | ||
1b56ff3d | 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; | |
34fee935 | 663 | const char *display; |
1b56ff3d | 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 | ||
34fee935 | 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 | ||
1b56ff3d | 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 | |
2e437378 | 706 | client_process_control(fd_set *readset) |
1b56ff3d | 707 | { |
708 | Buffer m; | |
709 | Channel *c; | |
34fee935 | 710 | int client_fd, new_fd[3], ver, allowed; |
1b56ff3d | 711 | socklen_t addrlen; |
712 | struct sockaddr_storage addr; | |
713 | struct confirm_ctx *cctx; | |
714 | char *cmd; | |
34fee935 | 715 | u_int i, len, env_len, command, flags; |
1b56ff3d | 716 | uid_t euid; |
717 | gid_t egid; | |
e00da40d | 718 | int listen_port = 0; |
719 | int connect_port = 0; | |
720 | char * listen_host = NULL; | |
721 | char * connect_host = NULL; | |
1b56ff3d | 722 | |
723 | /* | |
724 | * Accept connection on control socket | |
725 | */ | |
726 | if (control_fd == -1 || !FD_ISSET(control_fd, readset)) | |
727 | return; | |
728 | ||
729 | memset(&addr, 0, sizeof(addr)); | |
730 | addrlen = sizeof(addr); | |
731 | if ((client_fd = accept(control_fd, | |
732 | (struct sockaddr*)&addr, &addrlen)) == -1) { | |
733 | error("%s accept: %s", __func__, strerror(errno)); | |
734 | return; | |
735 | } | |
736 | ||
737 | if (getpeereid(client_fd, &euid, &egid) < 0) { | |
738 | error("%s getpeereid failed: %s", __func__, strerror(errno)); | |
739 | close(client_fd); | |
740 | return; | |
741 | } | |
742 | if ((euid != 0) && (getuid() != euid)) { | |
743 | error("control mode uid mismatch: peer euid %u != uid %u", | |
744 | (u_int) euid, (u_int) getuid()); | |
745 | close(client_fd); | |
746 | return; | |
747 | } | |
748 | ||
1b56ff3d | 749 | unset_nonblock(client_fd); |
750 | ||
34fee935 | 751 | /* Read command */ |
1b56ff3d | 752 | buffer_init(&m); |
34fee935 | 753 | if (ssh_msg_recv(client_fd, &m) == -1) { |
754 | error("%s: client msg_recv failed", __func__); | |
755 | close(client_fd); | |
756 | buffer_free(&m); | |
757 | return; | |
758 | } | |
759 | if ((ver = buffer_get_char(&m)) != SSHMUX_VER) { | |
760 | error("%s: wrong client version %d", __func__, ver); | |
761 | buffer_free(&m); | |
762 | close(client_fd); | |
763 | return; | |
764 | } | |
1b56ff3d | 765 | |
34fee935 | 766 | allowed = 1; |
767 | command = buffer_get_int(&m); | |
768 | flags = buffer_get_int(&m); | |
769 | ||
e00da40d | 770 | if (SSHMUX_FLAG_PORTFORWARD & flags) |
771 | { | |
772 | listen_host = buffer_get_string(&m,NULL); | |
773 | listen_port = buffer_get_int(&m); | |
774 | connect_host = buffer_get_string(&m,NULL); | |
775 | connect_port = buffer_get_int(&m); | |
776 | } | |
34fee935 | 777 | buffer_clear(&m); |
778 | ||
779 | switch (command) { | |
780 | case SSHMUX_COMMAND_OPEN: | |
781 | if (options.control_master == SSHCTL_MASTER_ASK || | |
782 | options.control_master == SSHCTL_MASTER_AUTO_ASK) | |
783 | allowed = ask_permission("Allow shared connection " | |
784 | "to %s? ", host); | |
785 | /* continue below */ | |
786 | break; | |
787 | case SSHMUX_COMMAND_TERMINATE: | |
788 | if (options.control_master == SSHCTL_MASTER_ASK || | |
789 | options.control_master == SSHCTL_MASTER_AUTO_ASK) | |
790 | allowed = ask_permission("Terminate shared connection " | |
791 | "to %s? ", host); | |
792 | if (allowed) | |
793 | quit_pending = 1; | |
794 | /* FALLTHROUGH */ | |
795 | case SSHMUX_COMMAND_ALIVE_CHECK: | |
796 | /* Reply for SSHMUX_COMMAND_TERMINATE and ALIVE_CHECK */ | |
797 | buffer_clear(&m); | |
798 | buffer_put_int(&m, allowed); | |
799 | buffer_put_int(&m, getpid()); | |
800 | if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) { | |
801 | error("%s: client msg_send failed", __func__); | |
802 | close(client_fd); | |
803 | buffer_free(&m); | |
804 | return; | |
805 | } | |
806 | buffer_free(&m); | |
807 | close(client_fd); | |
808 | return; | |
809 | default: | |
810 | error("Unsupported command %d", command); | |
811 | buffer_free(&m); | |
812 | close(client_fd); | |
813 | return; | |
814 | } | |
815 | ||
e00da40d | 816 | if (allowed && (SSHMUX_FLAG_PORTFORWARD & flags) && listen_host && connect_host) |
817 | { | |
818 | int ret; | |
819 | Forward * fwd; | |
820 | ||
821 | fwd = &options.local_forwards[options.num_local_forwards++]; | |
822 | fwd->listen_host = xstrdup(listen_host); | |
823 | fwd->listen_port = listen_port; | |
824 | fwd->connect_host = xstrdup(connect_host); | |
825 | fwd->connect_port = connect_port; | |
826 | ret = channel_setup_local_fwd_listener( | |
827 | options.local_forwards[options.num_local_forwards-1].listen_host, | |
828 | options.local_forwards[options.num_local_forwards-1].listen_port, | |
829 | options.local_forwards[options.num_local_forwards-1].connect_host, | |
830 | options.local_forwards[options.num_local_forwards-1].connect_port, | |
831 | options.gateway_ports, options.hpn_disabled, options.hpn_buffer_size); | |
832 | ||
833 | } | |
834 | ||
835 | ||
836 | if (listen_host) | |
837 | xfree(listen_host); | |
838 | if (connect_host) | |
839 | xfree(connect_host); | |
840 | ||
34fee935 | 841 | /* Reply for SSHMUX_COMMAND_OPEN */ |
842 | buffer_clear(&m); | |
1b56ff3d | 843 | buffer_put_int(&m, allowed); |
844 | buffer_put_int(&m, getpid()); | |
34fee935 | 845 | if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) { |
1b56ff3d | 846 | error("%s: client msg_send failed", __func__); |
847 | close(client_fd); | |
848 | buffer_free(&m); | |
849 | return; | |
850 | } | |
1b56ff3d | 851 | |
852 | if (!allowed) { | |
853 | error("Refused control connection"); | |
854 | close(client_fd); | |
855 | buffer_free(&m); | |
856 | return; | |
857 | } | |
858 | ||
34fee935 | 859 | buffer_clear(&m); |
1b56ff3d | 860 | if (ssh_msg_recv(client_fd, &m) == -1) { |
861 | error("%s: client msg_recv failed", __func__); | |
862 | close(client_fd); | |
863 | buffer_free(&m); | |
864 | return; | |
865 | } | |
34fee935 | 866 | if ((ver = buffer_get_char(&m)) != SSHMUX_VER) { |
1b56ff3d | 867 | error("%s: wrong client version %d", __func__, ver); |
868 | buffer_free(&m); | |
869 | close(client_fd); | |
870 | return; | |
871 | } | |
872 | ||
2e437378 | 873 | cctx = xcalloc(1, sizeof(*cctx)); |
34fee935 | 874 | cctx->want_tty = (flags & SSHMUX_FLAG_TTY) != 0; |
875 | cctx->want_subsys = (flags & SSHMUX_FLAG_SUBSYS) != 0; | |
876 | cctx->want_x_fwd = (flags & SSHMUX_FLAG_X11_FWD) != 0; | |
877 | cctx->want_agent_fwd = (flags & SSHMUX_FLAG_AGENT_FWD) != 0; | |
1b56ff3d | 878 | cctx->term = buffer_get_string(&m, &len); |
879 | ||
880 | cmd = buffer_get_string(&m, &len); | |
881 | buffer_init(&cctx->cmd); | |
882 | buffer_append(&cctx->cmd, cmd, strlen(cmd)); | |
883 | ||
884 | env_len = buffer_get_int(&m); | |
885 | env_len = MIN(env_len, 4096); | |
886 | debug3("%s: receiving %d env vars", __func__, env_len); | |
887 | if (env_len != 0) { | |
2e437378 | 888 | cctx->env = xcalloc(env_len + 1, sizeof(*cctx->env)); |
1b56ff3d | 889 | for (i = 0; i < env_len; i++) |
890 | cctx->env[i] = buffer_get_string(&m, &len); | |
891 | cctx->env[i] = NULL; | |
892 | } | |
893 | ||
894 | debug2("%s: accepted tty %d, subsys %d, cmd %s", __func__, | |
895 | cctx->want_tty, cctx->want_subsys, cmd); | |
2e437378 | 896 | xfree(cmd); |
1b56ff3d | 897 | |
898 | /* Gather fds from client */ | |
899 | new_fd[0] = mm_receive_fd(client_fd); | |
900 | new_fd[1] = mm_receive_fd(client_fd); | |
901 | new_fd[2] = mm_receive_fd(client_fd); | |
902 | ||
903 | debug2("%s: got fds stdin %d, stdout %d, stderr %d", __func__, | |
904 | new_fd[0], new_fd[1], new_fd[2]); | |
905 | ||
906 | /* Try to pick up ttymodes from client before it goes raw */ | |
907 | if (cctx->want_tty && tcgetattr(new_fd[0], &cctx->tio) == -1) | |
908 | error("%s: tcgetattr: %s", __func__, strerror(errno)); | |
909 | ||
34fee935 | 910 | /* This roundtrip is just for synchronisation of ttymodes */ |
1b56ff3d | 911 | buffer_clear(&m); |
34fee935 | 912 | if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) { |
1b56ff3d | 913 | error("%s: client msg_send failed", __func__); |
914 | close(client_fd); | |
915 | close(new_fd[0]); | |
916 | close(new_fd[1]); | |
917 | close(new_fd[2]); | |
918 | buffer_free(&m); | |
34fee935 | 919 | xfree(cctx->term); |
920 | if (env_len != 0) { | |
921 | for (i = 0; i < env_len; i++) | |
922 | xfree(cctx->env[i]); | |
923 | xfree(cctx->env); | |
924 | } | |
1b56ff3d | 925 | return; |
926 | } | |
927 | buffer_free(&m); | |
928 | ||
929 | /* enable nonblocking unless tty */ | |
930 | if (!isatty(new_fd[0])) | |
931 | set_nonblock(new_fd[0]); | |
932 | if (!isatty(new_fd[1])) | |
933 | set_nonblock(new_fd[1]); | |
934 | if (!isatty(new_fd[2])) | |
935 | set_nonblock(new_fd[2]); | |
936 | ||
937 | set_nonblock(client_fd); | |
938 | ||
e00da40d | 939 | if (options.hpn_disabled) |
940 | c = channel_new("session", SSH_CHANNEL_OPENING, | |
941 | new_fd[0], new_fd[1], new_fd[2], | |
942 | CHAN_SES_WINDOW_DEFAULT, CHAN_SES_PACKET_DEFAULT, | |
943 | CHAN_EXTENDED_WRITE, "client-session", /*nonblock*/0); | |
944 | else | |
945 | c = channel_new("session", SSH_CHANNEL_OPENING, | |
946 | new_fd[0], new_fd[1], new_fd[2], | |
947 | options.hpn_buffer_size, CHAN_SES_PACKET_DEFAULT, | |
948 | CHAN_EXTENDED_WRITE, "client-session", /*nonblock*/0); | |
1b56ff3d | 949 | /* XXX */ |
950 | c->ctl_fd = client_fd; | |
951 | ||
952 | debug3("%s: channel_new: %d", __func__, c->self); | |
953 | ||
954 | channel_send_open(c->self); | |
955 | channel_register_confirm(c->self, client_extra_session2_setup, cctx); | |
956 | } | |
957 | ||
2980ea68 | 958 | static void |
959 | process_cmdline(void) | |
960 | { | |
961 | void (*handler)(int); | |
34fee935 | 962 | char *s, *cmd, *cancel_host; |
1b56ff3d | 963 | int delete = 0; |
2980ea68 | 964 | int local = 0; |
34fee935 | 965 | u_short cancel_port; |
966 | Forward fwd; | |
2980ea68 | 967 | |
968 | leave_raw_mode(); | |
ff2d7a98 | 969 | handler = signal(SIGINT, SIG_IGN); |
2980ea68 | 970 | cmd = s = read_passphrase("\r\nssh> ", RP_ECHO); |
971 | if (s == NULL) | |
972 | goto out; | |
973 | while (*s && isspace(*s)) | |
974 | s++; | |
1b56ff3d | 975 | if (*s == '-') |
976 | s++; /* Skip cmdline '-', if any */ | |
977 | if (*s == '\0') | |
978 | goto out; | |
979 | ||
980 | if (*s == 'h' || *s == 'H' || *s == '?') { | |
981 | logit("Commands:"); | |
2e437378 | 982 | logit(" -L[bind_address:]port:host:hostport " |
983 | "Request local forward"); | |
984 | logit(" -R[bind_address:]port:host:hostport " | |
985 | "Request remote forward"); | |
986 | logit(" -KR[bind_address:]port " | |
987 | "Cancel remote forward"); | |
e00da40d | 988 | if (!options.permit_local_command) |
989 | goto out; | |
2e437378 | 990 | logit(" !args " |
991 | "Execute local command"); | |
e00da40d | 992 | goto out; |
993 | } | |
994 | ||
995 | if (*s == '!' && options.permit_local_command) { | |
996 | s++; | |
997 | ssh_local_cmd(s); | |
2980ea68 | 998 | goto out; |
1b56ff3d | 999 | } |
1000 | ||
1001 | if (*s == 'K') { | |
1002 | delete = 1; | |
1003 | s++; | |
1004 | } | |
1005 | if (*s != 'L' && *s != 'R') { | |
70791e56 | 1006 | logit("Invalid command."); |
2980ea68 | 1007 | goto out; |
1008 | } | |
1b56ff3d | 1009 | if (*s == 'L') |
2980ea68 | 1010 | local = 1; |
1b56ff3d | 1011 | if (local && delete) { |
1012 | logit("Not supported."); | |
1013 | goto out; | |
1014 | } | |
1015 | if ((!local || delete) && !compat20) { | |
70791e56 | 1016 | logit("Not supported for SSH protocol version 1."); |
2980ea68 | 1017 | goto out; |
1018 | } | |
1b56ff3d | 1019 | |
1020 | s++; | |
2980ea68 | 1021 | while (*s && isspace(*s)) |
1022 | s++; | |
1023 | ||
1b56ff3d | 1024 | if (delete) { |
34fee935 | 1025 | cancel_port = 0; |
1026 | cancel_host = hpdelim(&s); /* may be NULL */ | |
1027 | if (s != NULL) { | |
1028 | cancel_port = a2port(s); | |
1029 | cancel_host = cleanhostname(cancel_host); | |
1030 | } else { | |
1031 | cancel_port = a2port(cancel_host); | |
1032 | cancel_host = NULL; | |
1b56ff3d | 1033 | } |
34fee935 | 1034 | if (cancel_port == 0) { |
1035 | logit("Bad forwarding close port"); | |
1b56ff3d | 1036 | goto out; |
1037 | } | |
34fee935 | 1038 | channel_request_rforward_cancel(cancel_host, cancel_port); |
1b56ff3d | 1039 | } else { |
34fee935 | 1040 | if (!parse_forward(&fwd, s)) { |
1b56ff3d | 1041 | logit("Bad forwarding specification."); |
1042 | goto out; | |
1043 | } | |
1b56ff3d | 1044 | if (local) { |
34fee935 | 1045 | if (channel_setup_local_fwd_listener(fwd.listen_host, |
1046 | fwd.listen_port, fwd.connect_host, | |
e00da40d | 1047 | fwd.connect_port, options.gateway_ports, |
1048 | options.hpn_disabled, options.hpn_buffer_size) < 0) { | |
1b56ff3d | 1049 | logit("Port forwarding failed."); |
1050 | goto out; | |
1051 | } | |
34fee935 | 1052 | } else { |
2e437378 | 1053 | if (channel_request_remote_forwarding(fwd.listen_host, |
34fee935 | 1054 | fwd.listen_port, fwd.connect_host, |
2e437378 | 1055 | fwd.connect_port) < 0) { |
1056 | logit("Port forwarding failed."); | |
1057 | goto out; | |
1058 | } | |
34fee935 | 1059 | } |
1060 | ||
1b56ff3d | 1061 | logit("Forwarding port."); |
1062 | } | |
1063 | ||
2980ea68 | 1064 | out: |
1065 | signal(SIGINT, handler); | |
1066 | enter_raw_mode(); | |
1067 | if (cmd) | |
1068 | xfree(cmd); | |
1069 | } | |
1070 | ||
3c0ef626 | 1071 | /* process the characters one by one */ |
1072 | static int | |
1073 | process_escapes(Buffer *bin, Buffer *bout, Buffer *berr, char *buf, int len) | |
1074 | { | |
1075 | char string[1024]; | |
1076 | pid_t pid; | |
1077 | int bytes = 0; | |
1078 | u_int i; | |
1079 | u_char ch; | |
1080 | char *s; | |
1081 | ||
34fee935 | 1082 | if (len <= 0) |
1083 | return (0); | |
1084 | ||
1085 | for (i = 0; i < (u_int)len; i++) { | |
3c0ef626 | 1086 | /* Get one character at a time. */ |
1087 | ch = buf[i]; | |
1088 | ||
1089 | if (escape_pending) { | |
1090 | /* We have previously seen an escape character. */ | |
1091 | /* Clear the flag now. */ | |
1092 | escape_pending = 0; | |
1093 | ||
1094 | /* Process the escaped character. */ | |
1095 | switch (ch) { | |
1096 | case '.': | |
1097 | /* Terminate the connection. */ | |
1098 | snprintf(string, sizeof string, "%c.\r\n", escape_char); | |
1099 | buffer_append(berr, string, strlen(string)); | |
1100 | ||
1101 | quit_pending = 1; | |
1102 | return -1; | |
1103 | ||
1104 | case 'Z' - 64: | |
1105 | /* Suspend the program. */ | |
1106 | /* Print a message to that effect to the user. */ | |
1107 | snprintf(string, sizeof string, "%c^Z [suspend ssh]\r\n", escape_char); | |
1108 | buffer_append(berr, string, strlen(string)); | |
1109 | ||
1110 | /* Restore terminal modes and suspend. */ | |
1111 | client_suspend_self(bin, bout, berr); | |
1112 | ||
1113 | /* We have been continued. */ | |
1114 | continue; | |
1115 | ||
70791e56 | 1116 | case 'B': |
1117 | if (compat20) { | |
1118 | snprintf(string, sizeof string, | |
1119 | "%cB\r\n", escape_char); | |
1120 | buffer_append(berr, string, | |
1121 | strlen(string)); | |
1122 | channel_request_start(session_ident, | |
1123 | "break", 0); | |
1124 | packet_put_int(1000); | |
1125 | packet_send(); | |
1126 | } | |
1127 | continue; | |
1128 | ||
3c0ef626 | 1129 | case 'R': |
1130 | if (compat20) { | |
1131 | if (datafellows & SSH_BUG_NOREKEY) | |
70791e56 | 1132 | logit("Server does not support re-keying"); |
3c0ef626 | 1133 | else |
1134 | need_rekeying = 1; | |
1135 | } | |
1136 | continue; | |
1137 | ||
1138 | case '&': | |
1139 | /* | |
1140 | * Detach the program (continue to serve connections, | |
1141 | * but put in background and no more new connections). | |
1142 | */ | |
1143 | /* Restore tty modes. */ | |
1144 | leave_raw_mode(); | |
1145 | ||
1146 | /* Stop listening for new connections. */ | |
1147 | channel_stop_listening(); | |
1148 | ||
1149 | snprintf(string, sizeof string, | |
1150 | "%c& [backgrounded]\n", escape_char); | |
1151 | buffer_append(berr, string, strlen(string)); | |
1152 | ||
1153 | /* Fork into background. */ | |
1154 | pid = fork(); | |
1155 | if (pid < 0) { | |
1156 | error("fork: %.100s", strerror(errno)); | |
1157 | continue; | |
1158 | } | |
1159 | if (pid != 0) { /* This is the parent. */ | |
1160 | /* The parent just exits. */ | |
1161 | exit(0); | |
1162 | } | |
1163 | /* The child continues serving connections. */ | |
1164 | if (compat20) { | |
1165 | buffer_append(bin, "\004", 1); | |
1166 | /* fake EOF on stdin */ | |
1167 | return -1; | |
1168 | } else if (!stdin_eof) { | |
1169 | /* | |
1170 | * Sending SSH_CMSG_EOF alone does not always appear | |
1171 | * to be enough. So we try to send an EOF character | |
1172 | * first. | |
1173 | */ | |
1174 | packet_start(SSH_CMSG_STDIN_DATA); | |
1175 | packet_put_string("\004", 1); | |
1176 | packet_send(); | |
1177 | /* Close stdin. */ | |
1178 | stdin_eof = 1; | |
1179 | if (buffer_len(bin) == 0) { | |
1180 | packet_start(SSH_CMSG_EOF); | |
1181 | packet_send(); | |
1182 | } | |
1183 | } | |
1184 | continue; | |
1185 | ||
1186 | case '?': | |
1187 | snprintf(string, sizeof string, | |
1188 | "%c?\r\n\ | |
1189 | Supported escape sequences:\r\n\ | |
e54b3d7c | 1190 | %c. - terminate connection\r\n\ |
70791e56 | 1191 | %cB - send a BREAK to the remote system\r\n\ |
e54b3d7c | 1192 | %cC - open a command line\r\n\ |
1193 | %cR - Request rekey (SSH protocol 2 only)\r\n\ | |
1194 | %c^Z - suspend ssh\r\n\ | |
1195 | %c# - list forwarded connections\r\n\ | |
1196 | %c& - background ssh (when waiting for connections to terminate)\r\n\ | |
1197 | %c? - this message\r\n\ | |
1198 | %c%c - send the escape character by typing it twice\r\n\ | |
3c0ef626 | 1199 | (Note that escapes are only recognized immediately after newline.)\r\n", |
e54b3d7c | 1200 | escape_char, escape_char, escape_char, escape_char, |
1201 | escape_char, escape_char, escape_char, escape_char, | |
70791e56 | 1202 | escape_char, escape_char, escape_char); |
3c0ef626 | 1203 | buffer_append(berr, string, strlen(string)); |
1204 | continue; | |
1205 | ||
1206 | case '#': | |
1207 | snprintf(string, sizeof string, "%c#\r\n", escape_char); | |
1208 | buffer_append(berr, string, strlen(string)); | |
1209 | s = channel_open_message(); | |
1210 | buffer_append(berr, s, strlen(s)); | |
1211 | xfree(s); | |
1212 | continue; | |
1213 | ||
2980ea68 | 1214 | case 'C': |
1215 | process_cmdline(); | |
1216 | continue; | |
1217 | ||
3c0ef626 | 1218 | default: |
1219 | if (ch != escape_char) { | |
1220 | buffer_put_char(bin, escape_char); | |
1221 | bytes++; | |
1222 | } | |
1223 | /* Escaped characters fall through here */ | |
1224 | break; | |
1225 | } | |
1226 | } else { | |
1227 | /* | |
1228 | * The previous character was not an escape char. Check if this | |
1229 | * is an escape. | |
1230 | */ | |
1231 | if (last_was_cr && ch == escape_char) { | |
1232 | /* It is. Set the flag and continue to next character. */ | |
1233 | escape_pending = 1; | |
1234 | continue; | |
1235 | } | |
1236 | } | |
1237 | ||
1238 | /* | |
1239 | * Normal character. Record whether it was a newline, | |
1240 | * and append it to the buffer. | |
1241 | */ | |
1242 | last_was_cr = (ch == '\r' || ch == '\n'); | |
1243 | buffer_put_char(bin, ch); | |
1244 | bytes++; | |
1245 | } | |
1246 | return bytes; | |
1247 | } | |
1248 | ||
1249 | static void | |
2e437378 | 1250 | client_process_input(fd_set *readset) |
3c0ef626 | 1251 | { |
1252 | int len; | |
1253 | char buf[8192]; | |
1254 | ||
1255 | /* Read input from stdin. */ | |
1256 | if (FD_ISSET(fileno(stdin), readset)) { | |
1257 | /* Read as much as possible. */ | |
1258 | len = read(fileno(stdin), buf, sizeof(buf)); | |
1259 | if (len < 0 && (errno == EAGAIN || errno == EINTR)) | |
1260 | return; /* we'll try again later */ | |
1261 | if (len <= 0) { | |
1262 | /* | |
1263 | * Received EOF or error. They are treated | |
1264 | * similarly, except that an error message is printed | |
1265 | * if it was an error condition. | |
1266 | */ | |
1267 | if (len < 0) { | |
1268 | snprintf(buf, sizeof buf, "read: %.100s\r\n", strerror(errno)); | |
1269 | buffer_append(&stderr_buffer, buf, strlen(buf)); | |
1270 | } | |
1271 | /* Mark that we have seen EOF. */ | |
1272 | stdin_eof = 1; | |
1273 | /* | |
1274 | * Send an EOF message to the server unless there is | |
1275 | * data in the buffer. If there is data in the | |
1276 | * buffer, no message will be sent now. Code | |
1277 | * elsewhere will send the EOF when the buffer | |
1278 | * becomes empty if stdin_eof is set. | |
1279 | */ | |
1280 | if (buffer_len(&stdin_buffer) == 0) { | |
1281 | packet_start(SSH_CMSG_EOF); | |
1282 | packet_send(); | |
1283 | } | |
1284 | } else if (escape_char == SSH_ESCAPECHAR_NONE) { | |
1285 | /* | |
1286 | * Normal successful read, and no escape character. | |
1287 | * Just append the data to buffer. | |
1288 | */ | |
1289 | buffer_append(&stdin_buffer, buf, len); | |
1290 | } else { | |
1291 | /* | |
1292 | * Normal, successful read. But we have an escape character | |
1293 | * and have to process the characters one by one. | |
1294 | */ | |
1295 | if (process_escapes(&stdin_buffer, &stdout_buffer, | |
1296 | &stderr_buffer, buf, len) == -1) | |
1297 | return; | |
1298 | } | |
1299 | } | |
1300 | } | |
1301 | ||
1302 | static void | |
2e437378 | 1303 | client_process_output(fd_set *writeset) |
3c0ef626 | 1304 | { |
1305 | int len; | |
1306 | char buf[100]; | |
1307 | ||
1308 | /* Write buffered output to stdout. */ | |
1309 | if (FD_ISSET(fileno(stdout), writeset)) { | |
1310 | /* Write as much data as possible. */ | |
1311 | len = write(fileno(stdout), buffer_ptr(&stdout_buffer), | |
1312 | buffer_len(&stdout_buffer)); | |
1313 | if (len <= 0) { | |
1314 | if (errno == EINTR || errno == EAGAIN) | |
1315 | len = 0; | |
1316 | else { | |
1317 | /* | |
1318 | * An error or EOF was encountered. Put an | |
1319 | * error message to stderr buffer. | |
1320 | */ | |
1321 | snprintf(buf, sizeof buf, "write stdout: %.50s\r\n", strerror(errno)); | |
1322 | buffer_append(&stderr_buffer, buf, strlen(buf)); | |
1323 | quit_pending = 1; | |
1324 | return; | |
1325 | } | |
1326 | } | |
1327 | /* Consume printed data from the buffer. */ | |
1328 | buffer_consume(&stdout_buffer, len); | |
1329 | stdout_bytes += len; | |
1330 | } | |
1331 | /* Write buffered output to stderr. */ | |
1332 | if (FD_ISSET(fileno(stderr), writeset)) { | |
1333 | /* Write as much data as possible. */ | |
1334 | len = write(fileno(stderr), buffer_ptr(&stderr_buffer), | |
1335 | buffer_len(&stderr_buffer)); | |
1336 | if (len <= 0) { | |
1337 | if (errno == EINTR || errno == EAGAIN) | |
1338 | len = 0; | |
1339 | else { | |
1340 | /* EOF or error, but can't even print error message. */ | |
1341 | quit_pending = 1; | |
1342 | return; | |
1343 | } | |
1344 | } | |
1345 | /* Consume printed characters from the buffer. */ | |
1346 | buffer_consume(&stderr_buffer, len); | |
1347 | stderr_bytes += len; | |
1348 | } | |
1349 | } | |
1350 | ||
1351 | /* | |
1352 | * Get packets from the connection input buffer, and process them as long as | |
1353 | * there are packets available. | |
1354 | * | |
1355 | * Any unknown packets received during the actual | |
1356 | * session cause the session to terminate. This is | |
1357 | * intended to make debugging easier since no | |
1358 | * confirmations are sent. Any compatible protocol | |
1359 | * extensions must be negotiated during the | |
1360 | * preparatory phase. | |
1361 | */ | |
1362 | ||
1363 | static void | |
1364 | client_process_buffered_input_packets(void) | |
1365 | { | |
1366 | dispatch_run(DISPATCH_NONBLOCK, &quit_pending, compat20 ? xxx_kex : NULL); | |
1367 | } | |
1368 | ||
1369 | /* scan buf[] for '~' before sending data to the peer */ | |
1370 | ||
1371 | static int | |
1372 | simple_escape_filter(Channel *c, char *buf, int len) | |
1373 | { | |
1374 | /* XXX we assume c->extended is writeable */ | |
1375 | return process_escapes(&c->input, &c->output, &c->extended, buf, len); | |
1376 | } | |
1377 | ||
1378 | static void | |
1379 | client_channel_closed(int id, void *arg) | |
1380 | { | |
3c0ef626 | 1381 | channel_cancel_cleanup(id); |
1382 | session_closed = 1; | |
416fd2a8 | 1383 | leave_raw_mode(); |
3c0ef626 | 1384 | } |
1385 | ||
1386 | /* | |
1387 | * Implements the interactive session with the server. This is called after | |
1388 | * the user has been authenticated, and a command has been started on the | |
1389 | * remote host. If escape_char != SSH_ESCAPECHAR_NONE, it is the character | |
1390 | * used as an escape character for terminating or suspending the session. | |
1391 | */ | |
1392 | ||
1393 | int | |
1394 | client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id) | |
1395 | { | |
1396 | fd_set *readset = NULL, *writeset = NULL; | |
1397 | double start_time, total_time; | |
1b56ff3d | 1398 | int max_fd = 0, max_fd2 = 0, len, rekeying = 0; |
1399 | u_int nalloc = 0; | |
3c0ef626 | 1400 | char buf[100]; |
1401 | ||
1402 | debug("Entering interactive session."); | |
1403 | ||
1404 | start_time = get_current_time(); | |
1405 | ||
1406 | /* Initialize variables. */ | |
1407 | escape_pending = 0; | |
1408 | last_was_cr = 1; | |
1409 | exit_status = -1; | |
1410 | stdin_eof = 0; | |
1411 | buffer_high = 64 * 1024; | |
1412 | connection_in = packet_get_connection_in(); | |
1413 | connection_out = packet_get_connection_out(); | |
1414 | max_fd = MAX(connection_in, connection_out); | |
1b56ff3d | 1415 | if (control_fd != -1) |
1416 | max_fd = MAX(max_fd, control_fd); | |
3c0ef626 | 1417 | |
1418 | if (!compat20) { | |
1419 | /* enable nonblocking unless tty */ | |
1420 | if (!isatty(fileno(stdin))) | |
1421 | set_nonblock(fileno(stdin)); | |
1422 | if (!isatty(fileno(stdout))) | |
1423 | set_nonblock(fileno(stdout)); | |
1424 | if (!isatty(fileno(stderr))) | |
1425 | set_nonblock(fileno(stderr)); | |
1426 | max_fd = MAX(max_fd, fileno(stdin)); | |
1427 | max_fd = MAX(max_fd, fileno(stdout)); | |
1428 | max_fd = MAX(max_fd, fileno(stderr)); | |
1429 | } | |
1430 | stdin_bytes = 0; | |
1431 | stdout_bytes = 0; | |
1432 | stderr_bytes = 0; | |
1433 | quit_pending = 0; | |
1434 | escape_char = escape_char_arg; | |
1435 | ||
1436 | /* Initialize buffers. */ | |
1437 | buffer_init(&stdin_buffer); | |
1438 | buffer_init(&stdout_buffer); | |
1439 | buffer_init(&stderr_buffer); | |
1440 | ||
1441 | client_init_dispatch(); | |
1442 | ||
1c14df9e | 1443 | /* |
1444 | * Set signal handlers, (e.g. to restore non-blocking mode) | |
1445 | * but don't overwrite SIG_IGN, matches behaviour from rsh(1) | |
1446 | */ | |
34fee935 | 1447 | if (signal(SIGHUP, SIG_IGN) != SIG_IGN) |
1448 | signal(SIGHUP, signal_handler); | |
1c14df9e | 1449 | if (signal(SIGINT, SIG_IGN) != SIG_IGN) |
1450 | signal(SIGINT, signal_handler); | |
1451 | if (signal(SIGQUIT, SIG_IGN) != SIG_IGN) | |
1452 | signal(SIGQUIT, signal_handler); | |
1453 | if (signal(SIGTERM, SIG_IGN) != SIG_IGN) | |
1454 | signal(SIGTERM, signal_handler); | |
34fee935 | 1455 | signal(SIGWINCH, window_change_handler); |
3c0ef626 | 1456 | |
1457 | if (have_pty) | |
1458 | enter_raw_mode(); | |
1459 | ||
1460 | if (compat20) { | |
1461 | session_ident = ssh2_chan_id; | |
1462 | if (escape_char != SSH_ESCAPECHAR_NONE) | |
1463 | channel_register_filter(session_ident, | |
e00da40d | 1464 | simple_escape_filter, NULL); |
3c0ef626 | 1465 | if (session_ident != -1) |
1466 | channel_register_cleanup(session_ident, | |
e00da40d | 1467 | client_channel_closed, 0); |
3c0ef626 | 1468 | } else { |
1469 | /* Check if we should immediately send eof on stdin. */ | |
1470 | client_check_initial_eof_on_stdin(); | |
1471 | } | |
1472 | ||
1473 | /* Main loop of the client for the interactive session mode. */ | |
1474 | while (!quit_pending) { | |
1475 | ||
1476 | /* Process buffered packets sent by the server. */ | |
1477 | client_process_buffered_input_packets(); | |
1478 | ||
1479 | if (compat20 && session_closed && !channel_still_open()) | |
1480 | break; | |
1481 | ||
1482 | rekeying = (xxx_kex != NULL && !xxx_kex->done); | |
1483 | ||
1484 | if (rekeying) { | |
1485 | debug("rekeying in progress"); | |
1486 | } else { | |
1487 | /* | |
1488 | * Make packets of buffered stdin data, and buffer | |
1489 | * them for sending to the server. | |
1490 | */ | |
1491 | if (!compat20) | |
1492 | client_make_packets_from_stdin_data(); | |
1493 | ||
1494 | /* | |
1495 | * Make packets from buffered channel data, and | |
1496 | * enqueue them for sending to the server. | |
1497 | */ | |
1498 | if (packet_not_very_much_data_to_write()) | |
1499 | channel_output_poll(); | |
1500 | ||
1501 | /* | |
1502 | * Check if the window size has changed, and buffer a | |
1503 | * message about it to the server if so. | |
1504 | */ | |
1505 | client_check_window_change(); | |
1506 | ||
1507 | if (quit_pending) | |
1508 | break; | |
1509 | } | |
1510 | /* | |
1511 | * Wait until we have something to do (something becomes | |
1512 | * available on one of the descriptors). | |
1513 | */ | |
1514 | max_fd2 = max_fd; | |
1515 | client_wait_until_can_do_something(&readset, &writeset, | |
1516 | &max_fd2, &nalloc, rekeying); | |
1517 | ||
1518 | if (quit_pending) | |
1519 | break; | |
1520 | ||
1521 | /* Do channel operations unless rekeying in progress. */ | |
1522 | if (!rekeying) { | |
1523 | channel_after_select(readset, writeset); | |
70791e56 | 1524 | if (need_rekeying || packet_need_rekeying()) { |
1525 | debug("need rekeying"); | |
3c0ef626 | 1526 | xxx_kex->done = 0; |
1527 | kex_send_kexinit(xxx_kex); | |
1528 | need_rekeying = 0; | |
1529 | } | |
1530 | } | |
1531 | ||
1532 | /* Buffer input from the connection. */ | |
1533 | client_process_net_input(readset); | |
1534 | ||
1b56ff3d | 1535 | /* Accept control connections. */ |
1536 | client_process_control(readset); | |
1537 | ||
3c0ef626 | 1538 | if (quit_pending) |
1539 | break; | |
1540 | ||
1541 | if (!compat20) { | |
1542 | /* Buffer data from stdin */ | |
1543 | client_process_input(readset); | |
1544 | /* | |
1545 | * Process output to stdout and stderr. Output to | |
1546 | * the connection is processed elsewhere (above). | |
1547 | */ | |
1548 | client_process_output(writeset); | |
1549 | } | |
1550 | ||
1551 | /* Send as much buffered packet data as possible to the sender. */ | |
1552 | if (FD_ISSET(connection_out, writeset)) | |
1553 | packet_write_poll(); | |
1554 | } | |
1555 | if (readset) | |
1556 | xfree(readset); | |
1557 | if (writeset) | |
1558 | xfree(writeset); | |
1559 | ||
1560 | /* Terminate the session. */ | |
1561 | ||
1562 | /* Stop watching for window change. */ | |
34fee935 | 1563 | signal(SIGWINCH, SIG_DFL); |
3c0ef626 | 1564 | |
1565 | channel_free_all(); | |
1566 | ||
1567 | if (have_pty) | |
1568 | leave_raw_mode(); | |
1569 | ||
1570 | /* restore blocking io */ | |
1571 | if (!isatty(fileno(stdin))) | |
1572 | unset_nonblock(fileno(stdin)); | |
1573 | if (!isatty(fileno(stdout))) | |
1574 | unset_nonblock(fileno(stdout)); | |
1575 | if (!isatty(fileno(stderr))) | |
1576 | unset_nonblock(fileno(stderr)); | |
1577 | ||
416fd2a8 | 1578 | /* |
1579 | * If there was no shell or command requested, there will be no remote | |
1580 | * exit status to be returned. In that case, clear error code if the | |
1581 | * connection was deliberately terminated at this end. | |
1582 | */ | |
1583 | if (no_shell_flag && received_signal == SIGTERM) { | |
1584 | received_signal = 0; | |
1585 | exit_status = 0; | |
3c0ef626 | 1586 | } |
1587 | ||
416fd2a8 | 1588 | if (received_signal) |
1589 | fatal("Killed by signal %d.", (int) received_signal); | |
1590 | ||
3c0ef626 | 1591 | /* |
1592 | * In interactive mode (with pseudo tty) display a message indicating | |
1593 | * that the connection has been closed. | |
1594 | */ | |
1595 | if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) { | |
1596 | snprintf(buf, sizeof buf, "Connection to %.64s closed.\r\n", host); | |
1597 | buffer_append(&stderr_buffer, buf, strlen(buf)); | |
1598 | } | |
1599 | ||
1600 | /* Output any buffered data for stdout. */ | |
1601 | while (buffer_len(&stdout_buffer) > 0) { | |
1602 | len = write(fileno(stdout), buffer_ptr(&stdout_buffer), | |
1603 | buffer_len(&stdout_buffer)); | |
1604 | if (len <= 0) { | |
1605 | error("Write failed flushing stdout buffer."); | |
1606 | break; | |
1607 | } | |
1608 | buffer_consume(&stdout_buffer, len); | |
1609 | stdout_bytes += len; | |
1610 | } | |
1611 | ||
1612 | /* Output any buffered data for stderr. */ | |
1613 | while (buffer_len(&stderr_buffer) > 0) { | |
1614 | len = write(fileno(stderr), buffer_ptr(&stderr_buffer), | |
1615 | buffer_len(&stderr_buffer)); | |
1616 | if (len <= 0) { | |
1617 | error("Write failed flushing stderr buffer."); | |
1618 | break; | |
1619 | } | |
1620 | buffer_consume(&stderr_buffer, len); | |
1621 | stderr_bytes += len; | |
1622 | } | |
1623 | ||
1624 | /* Clear and free any buffers. */ | |
1625 | memset(buf, 0, sizeof(buf)); | |
1626 | buffer_free(&stdin_buffer); | |
1627 | buffer_free(&stdout_buffer); | |
1628 | buffer_free(&stderr_buffer); | |
1629 | ||
1630 | /* Report bytes transferred, and transfer rates. */ | |
1631 | total_time = get_current_time() - start_time; | |
1632 | debug("Transferred: stdin %lu, stdout %lu, stderr %lu bytes in %.1f seconds", | |
e9a17296 | 1633 | stdin_bytes, stdout_bytes, stderr_bytes, total_time); |
3c0ef626 | 1634 | if (total_time > 0) |
1635 | debug("Bytes per second: stdin %.1f, stdout %.1f, stderr %.1f", | |
e9a17296 | 1636 | stdin_bytes / total_time, stdout_bytes / total_time, |
1637 | stderr_bytes / total_time); | |
3c0ef626 | 1638 | |
1639 | /* Return the exit status of the program. */ | |
1640 | debug("Exit status %d", exit_status); | |
1641 | return exit_status; | |
1642 | } | |
1643 | ||
1644 | /*********/ | |
1645 | ||
1646 | static void | |
e9a17296 | 1647 | client_input_stdout_data(int type, u_int32_t seq, void *ctxt) |
3c0ef626 | 1648 | { |
1649 | u_int data_len; | |
1650 | char *data = packet_get_string(&data_len); | |
e9a17296 | 1651 | packet_check_eom(); |
3c0ef626 | 1652 | buffer_append(&stdout_buffer, data, data_len); |
1653 | memset(data, 0, data_len); | |
1654 | xfree(data); | |
1655 | } | |
1656 | static void | |
e9a17296 | 1657 | client_input_stderr_data(int type, u_int32_t seq, void *ctxt) |
3c0ef626 | 1658 | { |
1659 | u_int data_len; | |
1660 | char *data = packet_get_string(&data_len); | |
e9a17296 | 1661 | packet_check_eom(); |
3c0ef626 | 1662 | buffer_append(&stderr_buffer, data, data_len); |
1663 | memset(data, 0, data_len); | |
1664 | xfree(data); | |
1665 | } | |
1666 | static void | |
e9a17296 | 1667 | client_input_exit_status(int type, u_int32_t seq, void *ctxt) |
3c0ef626 | 1668 | { |
3c0ef626 | 1669 | exit_status = packet_get_int(); |
e9a17296 | 1670 | packet_check_eom(); |
3c0ef626 | 1671 | /* Acknowledge the exit. */ |
1672 | packet_start(SSH_CMSG_EXIT_CONFIRMATION); | |
1673 | packet_send(); | |
1674 | /* | |
1675 | * Must wait for packet to be sent since we are | |
1676 | * exiting the loop. | |
1677 | */ | |
1678 | packet_write_wait(); | |
1679 | /* Flag that we want to exit. */ | |
1680 | quit_pending = 1; | |
1681 | } | |
416fd2a8 | 1682 | static void |
1683 | client_input_agent_open(int type, u_int32_t seq, void *ctxt) | |
1684 | { | |
1685 | Channel *c = NULL; | |
1686 | int remote_id, sock; | |
1687 | ||
1688 | /* Read the remote channel number from the message. */ | |
1689 | remote_id = packet_get_int(); | |
1690 | packet_check_eom(); | |
1691 | ||
1692 | /* | |
1693 | * Get a connection to the local authentication agent (this may again | |
1694 | * get forwarded). | |
1695 | */ | |
1696 | sock = ssh_get_authentication_socket(); | |
1697 | ||
1698 | /* | |
1699 | * If we could not connect the agent, send an error message back to | |
1700 | * the server. This should never happen unless the agent dies, | |
1701 | * because authentication forwarding is only enabled if we have an | |
1702 | * agent. | |
1703 | */ | |
1704 | if (sock >= 0) { | |
1705 | c = channel_new("", SSH_CHANNEL_OPEN, sock, sock, | |
1706 | -1, 0, 0, 0, "authentication agent connection", 1); | |
1707 | c->remote_id = remote_id; | |
1708 | c->force_drain = 1; | |
1709 | } | |
1710 | if (c == NULL) { | |
1711 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
1712 | packet_put_int(remote_id); | |
1713 | } else { | |
1714 | /* Send a confirmation to the remote host. */ | |
1715 | debug("Forwarding authentication connection."); | |
1716 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1717 | packet_put_int(remote_id); | |
1718 | packet_put_int(c->self); | |
1719 | } | |
1720 | packet_send(); | |
1721 | } | |
3c0ef626 | 1722 | |
1723 | static Channel * | |
1724 | client_request_forwarded_tcpip(const char *request_type, int rchan) | |
1725 | { | |
e54b3d7c | 1726 | Channel *c = NULL; |
3c0ef626 | 1727 | char *listen_address, *originator_address; |
1728 | int listen_port, originator_port; | |
1729 | int sock; | |
1730 | ||
1731 | /* Get rest of the packet */ | |
1732 | listen_address = packet_get_string(NULL); | |
1733 | listen_port = packet_get_int(); | |
1734 | originator_address = packet_get_string(NULL); | |
1735 | originator_port = packet_get_int(); | |
e9a17296 | 1736 | packet_check_eom(); |
3c0ef626 | 1737 | |
1738 | debug("client_request_forwarded_tcpip: listen %s port %d, originator %s port %d", | |
1739 | listen_address, listen_port, originator_address, originator_port); | |
1740 | ||
1741 | sock = channel_connect_by_listen_address(listen_port); | |
1742 | if (sock < 0) { | |
1743 | xfree(originator_address); | |
1744 | xfree(listen_address); | |
1745 | return NULL; | |
1746 | } | |
e00da40d | 1747 | if (options.hpn_disabled) |
1748 | c = channel_new("forwarded-tcpip", | |
1749 | SSH_CHANNEL_CONNECTING, sock, sock, -1, | |
1750 | CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0, | |
1751 | originator_address, 1); | |
1752 | else | |
1753 | c = channel_new("forwarded-tcpip", | |
1754 | SSH_CHANNEL_CONNECTING, sock, sock, -1, | |
1755 | options.hpn_buffer_size, options.hpn_buffer_size, 0, | |
1756 | originator_address, 1); | |
3c0ef626 | 1757 | xfree(originator_address); |
1758 | xfree(listen_address); | |
1759 | return c; | |
1760 | } | |
1761 | ||
e54b3d7c | 1762 | static Channel * |
3c0ef626 | 1763 | client_request_x11(const char *request_type, int rchan) |
1764 | { | |
1765 | Channel *c = NULL; | |
1766 | char *originator; | |
1767 | int originator_port; | |
1768 | int sock; | |
1769 | ||
1770 | if (!options.forward_x11) { | |
1771 | error("Warning: ssh server tried X11 forwarding."); | |
e00da40d | 1772 | error("Warning: this is probably a break-in attempt by a malicious server."); |
3c0ef626 | 1773 | return NULL; |
1774 | } | |
1775 | originator = packet_get_string(NULL); | |
1776 | if (datafellows & SSH_BUG_X11FWD) { | |
1777 | debug2("buggy server: x11 request w/o originator_port"); | |
1778 | originator_port = 0; | |
1779 | } else { | |
1780 | originator_port = packet_get_int(); | |
1781 | } | |
e9a17296 | 1782 | packet_check_eom(); |
3c0ef626 | 1783 | /* XXX check permission */ |
1784 | debug("client_request_x11: request from %s %d", originator, | |
1785 | originator_port); | |
1786 | xfree(originator); | |
1787 | sock = x11_connect_display(); | |
1788 | if (sock < 0) | |
1789 | return NULL; | |
e00da40d | 1790 | if (options.hpn_disabled) |
1791 | c = channel_new("x11", | |
1792 | SSH_CHANNEL_X11_OPEN, sock, sock, -1, | |
1793 | CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1); | |
1794 | else | |
1795 | c = channel_new("x11", | |
1796 | SSH_CHANNEL_X11_OPEN, sock, sock, -1, | |
1797 | options.hpn_buffer_size, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1); | |
3c0ef626 | 1798 | c->force_drain = 1; |
1799 | return c; | |
1800 | } | |
1801 | ||
e54b3d7c | 1802 | static Channel * |
3c0ef626 | 1803 | client_request_agent(const char *request_type, int rchan) |
1804 | { | |
1805 | Channel *c = NULL; | |
1806 | int sock; | |
1807 | ||
1808 | if (!options.forward_agent) { | |
1809 | error("Warning: ssh server tried agent forwarding."); | |
e00da40d | 1810 | error("Warning: this is probably a break-in attempt by a malicious server."); |
3c0ef626 | 1811 | return NULL; |
1812 | } | |
1813 | sock = ssh_get_authentication_socket(); | |
1814 | if (sock < 0) | |
1815 | return NULL; | |
e00da40d | 1816 | if (options.hpn_disabled) |
1817 | c = channel_new("authentication agent connection", | |
1818 | SSH_CHANNEL_OPEN, sock, sock, -1, | |
1819 | CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0, | |
1820 | "authentication agent connection", 1); | |
1821 | else | |
1822 | c = channel_new("authentication agent connection", | |
1823 | SSH_CHANNEL_OPEN, sock, sock, -1, | |
1824 | options.hpn_buffer_size, options.hpn_buffer_size, 0, | |
1825 | "authentication agent connection", 1); | |
3c0ef626 | 1826 | c->force_drain = 1; |
1827 | return c; | |
1828 | } | |
1829 | ||
1830 | /* XXXX move to generic input handler */ | |
1831 | static void | |
e9a17296 | 1832 | client_input_channel_open(int type, u_int32_t seq, void *ctxt) |
3c0ef626 | 1833 | { |
1834 | Channel *c = NULL; | |
1835 | char *ctype; | |
3c0ef626 | 1836 | int rchan; |
ff2d7a98 | 1837 | u_int rmaxpack, rwindow, len; |
3c0ef626 | 1838 | |
1839 | ctype = packet_get_string(&len); | |
1840 | rchan = packet_get_int(); | |
1841 | rwindow = packet_get_int(); | |
1842 | rmaxpack = packet_get_int(); | |
1843 | ||
1844 | debug("client_input_channel_open: ctype %s rchan %d win %d max %d", | |
1845 | ctype, rchan, rwindow, rmaxpack); | |
1846 | ||
1847 | if (strcmp(ctype, "forwarded-tcpip") == 0) { | |
1848 | c = client_request_forwarded_tcpip(ctype, rchan); | |
1849 | } else if (strcmp(ctype, "x11") == 0) { | |
1850 | c = client_request_x11(ctype, rchan); | |
1851 | } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) { | |
1852 | c = client_request_agent(ctype, rchan); | |
1853 | } | |
1854 | /* XXX duplicate : */ | |
1855 | if (c != NULL) { | |
1856 | debug("confirm %s", ctype); | |
1857 | c->remote_id = rchan; | |
1858 | c->remote_window = rwindow; | |
1859 | c->remote_maxpacket = rmaxpack; | |
1860 | if (c->type != SSH_CHANNEL_CONNECTING) { | |
1861 | packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1862 | packet_put_int(c->remote_id); | |
1863 | packet_put_int(c->self); | |
1864 | packet_put_int(c->local_window); | |
1865 | packet_put_int(c->local_maxpacket); | |
1866 | packet_send(); | |
1867 | } | |
1868 | } else { | |
1869 | debug("failure %s", ctype); | |
1870 | packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE); | |
1871 | packet_put_int(rchan); | |
1872 | packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED); | |
1873 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { | |
1874 | packet_put_cstring("open failed"); | |
1875 | packet_put_cstring(""); | |
1876 | } | |
1877 | packet_send(); | |
1878 | } | |
1879 | xfree(ctype); | |
1880 | } | |
1881 | static void | |
e9a17296 | 1882 | client_input_channel_req(int type, u_int32_t seq, void *ctxt) |
3c0ef626 | 1883 | { |
1884 | Channel *c = NULL; | |
1b56ff3d | 1885 | int exitval, id, reply, success = 0; |
3c0ef626 | 1886 | char *rtype; |
1887 | ||
1888 | id = packet_get_int(); | |
1889 | rtype = packet_get_string(NULL); | |
1890 | reply = packet_get_char(); | |
1891 | ||
1892 | debug("client_input_channel_req: channel %d rtype %s reply %d", | |
1893 | id, rtype, reply); | |
1894 | ||
1b56ff3d | 1895 | if (id == -1) { |
1896 | error("client_input_channel_req: request for channel -1"); | |
1897 | } else if ((c = channel_lookup(id)) == NULL) { | |
3c0ef626 | 1898 | error("client_input_channel_req: channel %d: unknown channel", id); |
1899 | } else if (strcmp(rtype, "exit-status") == 0) { | |
1b56ff3d | 1900 | exitval = packet_get_int(); |
1901 | if (id == session_ident) { | |
1902 | success = 1; | |
1903 | exit_status = exitval; | |
1904 | } else if (c->ctl_fd == -1) { | |
1905 | error("client_input_channel_req: unexpected channel %d", | |
1906 | session_ident); | |
1907 | } else { | |
1908 | atomicio(vwrite, c->ctl_fd, &exitval, sizeof(exitval)); | |
1909 | success = 1; | |
1910 | } | |
e9a17296 | 1911 | packet_check_eom(); |
3c0ef626 | 1912 | } |
1913 | if (reply) { | |
1914 | packet_start(success ? | |
1915 | SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE); | |
1b56ff3d | 1916 | packet_put_int(id); |
3c0ef626 | 1917 | packet_send(); |
1918 | } | |
1919 | xfree(rtype); | |
1920 | } | |
e9a17296 | 1921 | static void |
1922 | client_input_global_request(int type, u_int32_t seq, void *ctxt) | |
1923 | { | |
1924 | char *rtype; | |
1925 | int want_reply; | |
1926 | int success = 0; | |
1927 | ||
1928 | rtype = packet_get_string(NULL); | |
1929 | want_reply = packet_get_char(); | |
416fd2a8 | 1930 | debug("client_input_global_request: rtype %s want_reply %d", |
1931 | rtype, want_reply); | |
e9a17296 | 1932 | if (want_reply) { |
1933 | packet_start(success ? | |
1934 | SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE); | |
1935 | packet_send(); | |
1936 | packet_write_wait(); | |
1937 | } | |
1938 | xfree(rtype); | |
1939 | } | |
3c0ef626 | 1940 | |
1b56ff3d | 1941 | void |
1942 | client_session2_setup(int id, int want_tty, int want_subsystem, | |
1943 | const char *term, struct termios *tiop, int in_fd, Buffer *cmd, char **env, | |
1944 | dispatch_fn *subsys_repl) | |
1945 | { | |
1946 | int len; | |
34fee935 | 1947 | Channel *c = NULL; |
1b56ff3d | 1948 | |
1949 | debug2("%s: id %d", __func__, id); | |
1950 | ||
34fee935 | 1951 | if ((c = channel_lookup(id)) == NULL) |
1952 | fatal("client_session2_setup: channel %d: unknown channel", id); | |
1953 | ||
1b56ff3d | 1954 | if (want_tty) { |
1955 | struct winsize ws; | |
1956 | struct termios tio; | |
1957 | ||
1958 | /* Store window size in the packet. */ | |
1959 | if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0) | |
1960 | memset(&ws, 0, sizeof(ws)); | |
1961 | ||
1962 | channel_request_start(id, "pty-req", 0); | |
1963 | packet_put_cstring(term != NULL ? term : ""); | |
2e437378 | 1964 | packet_put_int((u_int)ws.ws_col); |
1965 | packet_put_int((u_int)ws.ws_row); | |
1966 | packet_put_int((u_int)ws.ws_xpixel); | |
1967 | packet_put_int((u_int)ws.ws_ypixel); | |
1b56ff3d | 1968 | tio = get_saved_tio(); |
1969 | tty_make_modes(-1, tiop != NULL ? tiop : &tio); | |
1970 | packet_send(); | |
1971 | /* XXX wait for reply */ | |
34fee935 | 1972 | c->client_tty = 1; |
1b56ff3d | 1973 | } |
1974 | ||
1975 | /* Transfer any environment variables from client to server */ | |
1976 | if (options.num_send_env != 0 && env != NULL) { | |
1977 | int i, j, matched; | |
1978 | char *name, *val; | |
1979 | ||
1980 | debug("Sending environment."); | |
1981 | for (i = 0; env[i] != NULL; i++) { | |
1982 | /* Split */ | |
1983 | name = xstrdup(env[i]); | |
1984 | if ((val = strchr(name, '=')) == NULL) { | |
e00da40d | 1985 | xfree(name); |
1b56ff3d | 1986 | continue; |
1987 | } | |
1988 | *val++ = '\0'; | |
1989 | ||
1990 | matched = 0; | |
1991 | for (j = 0; j < options.num_send_env; j++) { | |
1992 | if (match_pattern(name, options.send_env[j])) { | |
1993 | matched = 1; | |
1994 | break; | |
1995 | } | |
1996 | } | |
1997 | if (!matched) { | |
1998 | debug3("Ignored env %s", name); | |
e00da40d | 1999 | xfree(name); |
1b56ff3d | 2000 | continue; |
2001 | } | |
2002 | ||
2003 | debug("Sending env %s = %s", name, val); | |
2004 | channel_request_start(id, "env", 0); | |
2005 | packet_put_cstring(name); | |
2006 | packet_put_cstring(val); | |
2007 | packet_send(); | |
e00da40d | 2008 | xfree(name); |
1b56ff3d | 2009 | } |
2010 | } | |
2011 | ||
2012 | len = buffer_len(cmd); | |
2013 | if (len > 0) { | |
2014 | if (len > 900) | |
2015 | len = 900; | |
2016 | if (want_subsystem) { | |
2017 | debug("Sending subsystem: %.*s", len, (u_char*)buffer_ptr(cmd)); | |
2018 | channel_request_start(id, "subsystem", subsys_repl != NULL); | |
2019 | if (subsys_repl != NULL) { | |
2020 | /* register callback for reply */ | |
2021 | /* XXX we assume that client_loop has already been called */ | |
2022 | dispatch_set(SSH2_MSG_CHANNEL_FAILURE, subsys_repl); | |
2023 | dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, subsys_repl); | |
2024 | } | |
2025 | } else { | |
2026 | debug("Sending command: %.*s", len, (u_char*)buffer_ptr(cmd)); | |
2027 | channel_request_start(id, "exec", 0); | |
2028 | } | |
2029 | packet_put_string(buffer_ptr(cmd), buffer_len(cmd)); | |
2030 | packet_send(); | |
2031 | } else { | |
2032 | channel_request_start(id, "shell", 0); | |
2033 | packet_send(); | |
2034 | } | |
2035 | } | |
2036 | ||
3c0ef626 | 2037 | static void |
2038 | client_init_dispatch_20(void) | |
2039 | { | |
2040 | dispatch_init(&dispatch_protocol_error); | |
2980ea68 | 2041 | |
3c0ef626 | 2042 | dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose); |
2043 | dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data); | |
2044 | dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof); | |
2045 | dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data); | |
2046 | dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open); | |
2047 | dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation); | |
2048 | dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure); | |
2049 | dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req); | |
2050 | dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust); | |
e9a17296 | 2051 | dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request); |
3c0ef626 | 2052 | |
2053 | /* rekeying */ | |
2054 | dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit); | |
2980ea68 | 2055 | |
2056 | /* global request reply messages */ | |
2057 | dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply); | |
2058 | dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply); | |
3c0ef626 | 2059 | } |
2060 | static void | |
2061 | client_init_dispatch_13(void) | |
2062 | { | |
2063 | dispatch_init(NULL); | |
2064 | dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close); | |
2065 | dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation); | |
2066 | dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data); | |
2067 | dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation); | |
2068 | dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure); | |
2069 | dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open); | |
2070 | dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status); | |
2071 | dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data); | |
2072 | dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data); | |
2073 | ||
2074 | dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ? | |
416fd2a8 | 2075 | &client_input_agent_open : &deny_input_open); |
3c0ef626 | 2076 | dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ? |
2077 | &x11_input_open : &deny_input_open); | |
2078 | } | |
2079 | static void | |
2080 | client_init_dispatch_15(void) | |
2081 | { | |
2082 | client_init_dispatch_13(); | |
2083 | dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof); | |
2084 | dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose); | |
2085 | } | |
2086 | static void | |
2087 | client_init_dispatch(void) | |
2088 | { | |
2089 | if (compat20) | |
2090 | client_init_dispatch_20(); | |
2091 | else if (compat13) | |
2092 | client_init_dispatch_13(); | |
2093 | else | |
2094 | client_init_dispatch_15(); | |
2095 | } | |
416fd2a8 | 2096 | |
2097 | /* client specific fatal cleanup */ | |
2098 | void | |
2099 | cleanup_exit(int i) | |
2100 | { | |
2101 | leave_raw_mode(); | |
2102 | leave_non_blocking(); | |
1b56ff3d | 2103 | if (options.control_path != NULL && control_fd != -1) |
2104 | unlink(options.control_path); | |
416fd2a8 | 2105 | _exit(i); |
2106 | } |