]>
Commit | Line | Data |
---|---|---|
1 | /* $OpenBSD: ssh.c,v 1.324 2009/02/12 03:00:56 djm Exp $ */ | |
2 | /* | |
3 | * Author: Tatu Ylonen <ylo@cs.hut.fi> | |
4 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland | |
5 | * All rights reserved | |
6 | * Ssh client program. This program can be used to log into a remote machine. | |
7 | * The software supports strong authentication, encryption, and forwarding | |
8 | * of X11, TCP/IP, and authentication connections. | |
9 | * | |
10 | * As far as I am concerned, the code I have written for this software | |
11 | * can be used freely for any purpose. Any derived versions of this | |
12 | * software must be clearly marked as such, and if the derived work is | |
13 | * incompatible with the protocol description in the RFC file, it must be | |
14 | * called by a name other than "ssh" or "Secure Shell". | |
15 | * | |
16 | * Copyright (c) 1999 Niels Provos. All rights reserved. | |
17 | * Copyright (c) 2000, 2001, 2002, 2003 Markus Friedl. All rights reserved. | |
18 | * | |
19 | * Modified to work with SSL by Niels Provos <provos@citi.umich.edu> | |
20 | * in Canada (German citizen). | |
21 | * | |
22 | * Redistribution and use in source and binary forms, with or without | |
23 | * modification, are permitted provided that the following conditions | |
24 | * are met: | |
25 | * 1. Redistributions of source code must retain the above copyright | |
26 | * notice, this list of conditions and the following disclaimer. | |
27 | * 2. Redistributions in binary form must reproduce the above copyright | |
28 | * notice, this list of conditions and the following disclaimer in the | |
29 | * documentation and/or other materials provided with the distribution. | |
30 | * | |
31 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR | |
32 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES | |
33 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. | |
34 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, | |
35 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | |
36 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | |
37 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | |
38 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
39 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | |
40 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
41 | */ | |
42 | ||
43 | #include "includes.h" | |
44 | ||
45 | #include <sys/types.h> | |
46 | #ifdef HAVE_SYS_STAT_H | |
47 | # include <sys/stat.h> | |
48 | #endif | |
49 | #include <sys/resource.h> | |
50 | #include <sys/ioctl.h> | |
51 | #include <sys/socket.h> | |
52 | ||
53 | #include <ctype.h> | |
54 | #include <errno.h> | |
55 | #include <fcntl.h> | |
56 | #include <netdb.h> | |
57 | #ifdef HAVE_PATHS_H | |
58 | #include <paths.h> | |
59 | #endif | |
60 | #include <pwd.h> | |
61 | #include <signal.h> | |
62 | #include <stdarg.h> | |
63 | #include <stddef.h> | |
64 | #include <stdio.h> | |
65 | #include <stdlib.h> | |
66 | #include <string.h> | |
67 | #include <unistd.h> | |
68 | ||
69 | #include <netinet/in.h> | |
70 | #include <arpa/inet.h> | |
71 | ||
72 | #include <openssl/evp.h> | |
73 | #include <openssl/err.h> | |
74 | #include "openbsd-compat/openssl-compat.h" | |
75 | #include "openbsd-compat/sys-queue.h" | |
76 | ||
77 | #include "xmalloc.h" | |
78 | #include "ssh.h" | |
79 | #include "ssh1.h" | |
80 | #include "ssh2.h" | |
81 | #include "compat.h" | |
82 | #include "cipher.h" | |
83 | #include "packet.h" | |
84 | #include "buffer.h" | |
85 | #include "channels.h" | |
86 | #include "key.h" | |
87 | #include "authfd.h" | |
88 | #include "authfile.h" | |
89 | #include "pathnames.h" | |
90 | #include "dispatch.h" | |
91 | #include "clientloop.h" | |
92 | #include "log.h" | |
93 | #include "readconf.h" | |
94 | #include "sshconnect.h" | |
95 | #include "misc.h" | |
96 | #include "kex.h" | |
97 | #include "mac.h" | |
98 | #include "sshpty.h" | |
99 | #include "match.h" | |
100 | #include "msg.h" | |
101 | #include "uidswap.h" | |
102 | #include "version.h" | |
103 | ||
104 | #ifdef SMARTCARD | |
105 | #include "scard.h" | |
106 | #endif | |
107 | ||
108 | extern char *__progname; | |
109 | ||
110 | /* Flag indicating whether debug mode is on. May be set on the command line. */ | |
111 | int debug_flag = 0; | |
112 | ||
113 | /* Flag indicating whether a tty should be allocated */ | |
114 | int tty_flag = 0; | |
115 | int no_tty_flag = 0; | |
116 | int force_tty_flag = 0; | |
117 | ||
118 | /* don't exec a shell */ | |
119 | int no_shell_flag = 0; | |
120 | ||
121 | /* | |
122 | * Flag indicating that nothing should be read from stdin. This can be set | |
123 | * on the command line. | |
124 | */ | |
125 | int stdin_null_flag = 0; | |
126 | ||
127 | /* | |
128 | * Flag indicating that ssh should fork after authentication. This is useful | |
129 | * so that the passphrase can be entered manually, and then ssh goes to the | |
130 | * background. | |
131 | */ | |
132 | int fork_after_authentication_flag = 0; | |
133 | ||
134 | /* | |
135 | * General data structure for command line options and options configurable | |
136 | * in configuration files. See readconf.h. | |
137 | */ | |
138 | Options options; | |
139 | ||
140 | /* optional user configfile */ | |
141 | char *config = NULL; | |
142 | ||
143 | /* | |
144 | * Name of the host we are connecting to. This is the name given on the | |
145 | * command line, or the HostName specified for the user-supplied name in a | |
146 | * configuration file. | |
147 | */ | |
148 | char *host; | |
149 | ||
150 | /* socket address the host resolves to */ | |
151 | struct sockaddr_storage hostaddr; | |
152 | ||
153 | /* Private host keys. */ | |
154 | Sensitive sensitive_data; | |
155 | ||
156 | /* Original real UID. */ | |
157 | uid_t original_real_uid; | |
158 | uid_t original_effective_uid; | |
159 | ||
160 | /* command to be executed */ | |
161 | Buffer command; | |
162 | ||
163 | /* Should we execute a command or invoke a subsystem? */ | |
164 | int subsystem_flag = 0; | |
165 | ||
166 | /* # of replies received for global requests */ | |
167 | static int remote_forward_confirms_received = 0; | |
168 | ||
169 | /* pid of proxycommand child process */ | |
170 | pid_t proxy_command_pid = 0; | |
171 | ||
172 | /* mux.c */ | |
173 | extern int muxserver_sock; | |
174 | extern u_int muxclient_command; | |
175 | ||
176 | /* Prints a help message to the user. This function never returns. */ | |
177 | ||
178 | static void | |
179 | usage(void) | |
180 | { | |
181 | fprintf(stderr, | |
182 | "usage: ssh [-1246AaCfgKkMNnqsTtVvXxYy] [-b bind_address] [-c cipher_spec]\n" | |
183 | " [-D [bind_address:]port] [-e escape_char] [-F configfile]\n" | |
184 | " [-i identity_file] [-L [bind_address:]port:host:hostport]\n" | |
185 | " [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n" | |
186 | " [-R [bind_address:]port:host:hostport] [-S ctl_path]\n" | |
187 | " [-w local_tun[:remote_tun]] [user@]hostname [command]\n" | |
188 | ); | |
189 | exit(255); | |
190 | } | |
191 | ||
192 | static int ssh_session(void); | |
193 | static int ssh_session2(void); | |
194 | static void load_public_identity_files(void); | |
195 | ||
196 | /* from muxclient.c */ | |
197 | void muxclient(const char *); | |
198 | void muxserver_listen(void); | |
199 | ||
200 | /* | |
201 | * Main program for the ssh client. | |
202 | */ | |
203 | int | |
204 | main(int ac, char **av) | |
205 | { | |
206 | int i, opt, exit_status, use_syslog; | |
207 | char *p, *cp, *line, buf[256]; | |
208 | struct stat st; | |
209 | struct passwd *pw; | |
210 | int dummy, timeout_ms; | |
211 | extern int optind, optreset; | |
212 | extern char *optarg; | |
213 | struct servent *sp; | |
214 | Forward fwd; | |
215 | ||
216 | /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ | |
217 | sanitise_stdfd(); | |
218 | ||
219 | __progname = ssh_get_progname(av[0]); | |
220 | init_rng(); | |
221 | ||
222 | /* | |
223 | * Save the original real uid. It will be needed later (uid-swapping | |
224 | * may clobber the real uid). | |
225 | */ | |
226 | original_real_uid = getuid(); | |
227 | original_effective_uid = geteuid(); | |
228 | ||
229 | /* | |
230 | * Use uid-swapping to give up root privileges for the duration of | |
231 | * option processing. We will re-instantiate the rights when we are | |
232 | * ready to create the privileged port, and will permanently drop | |
233 | * them when the port has been created (actually, when the connection | |
234 | * has been made, as we may need to create the port several times). | |
235 | */ | |
236 | PRIV_END; | |
237 | ||
238 | #ifdef HAVE_SETRLIMIT | |
239 | /* If we are installed setuid root be careful to not drop core. */ | |
240 | if (original_real_uid != original_effective_uid) { | |
241 | struct rlimit rlim; | |
242 | rlim.rlim_cur = rlim.rlim_max = 0; | |
243 | if (setrlimit(RLIMIT_CORE, &rlim) < 0) | |
244 | fatal("setrlimit failed: %.100s", strerror(errno)); | |
245 | } | |
246 | #endif | |
247 | /* Get user data. */ | |
248 | pw = getpwuid(original_real_uid); | |
249 | if (!pw) { | |
250 | logit("You don't exist, go away!"); | |
251 | exit(255); | |
252 | } | |
253 | /* Take a copy of the returned structure. */ | |
254 | pw = pwcopy(pw); | |
255 | ||
256 | /* | |
257 | * Set our umask to something reasonable, as some files are created | |
258 | * with the default umask. This will make them world-readable but | |
259 | * writable only by the owner, which is ok for all files for which we | |
260 | * don't set the modes explicitly. | |
261 | */ | |
262 | umask(022); | |
263 | ||
264 | /* | |
265 | * Initialize option structure to indicate that no values have been | |
266 | * set. | |
267 | */ | |
268 | initialize_options(&options); | |
269 | ||
270 | /* Parse command-line arguments. */ | |
271 | host = NULL; | |
272 | use_syslog = 0; | |
273 | ||
274 | again: | |
275 | while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx" | |
276 | "ACD:F:I:KL:MNO:PR:S:TVw:XYy")) != -1) { | |
277 | switch (opt) { | |
278 | case '1': | |
279 | options.protocol = SSH_PROTO_1; | |
280 | break; | |
281 | case '2': | |
282 | options.protocol = SSH_PROTO_2; | |
283 | break; | |
284 | case '4': | |
285 | options.address_family = AF_INET; | |
286 | break; | |
287 | case '6': | |
288 | options.address_family = AF_INET6; | |
289 | break; | |
290 | case 'n': | |
291 | stdin_null_flag = 1; | |
292 | break; | |
293 | case 'f': | |
294 | fork_after_authentication_flag = 1; | |
295 | stdin_null_flag = 1; | |
296 | break; | |
297 | case 'x': | |
298 | options.forward_x11 = 0; | |
299 | break; | |
300 | case 'X': | |
301 | options.forward_x11 = 1; | |
302 | break; | |
303 | case 'y': | |
304 | use_syslog = 1; | |
305 | break; | |
306 | case 'Y': | |
307 | options.forward_x11 = 1; | |
308 | options.forward_x11_trusted = 1; | |
309 | break; | |
310 | case 'g': | |
311 | options.gateway_ports = 1; | |
312 | break; | |
313 | case 'O': | |
314 | if (strcmp(optarg, "check") == 0) | |
315 | muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK; | |
316 | else if (strcmp(optarg, "exit") == 0) | |
317 | muxclient_command = SSHMUX_COMMAND_TERMINATE; | |
318 | else | |
319 | fatal("Invalid multiplex command."); | |
320 | break; | |
321 | case 'P': /* deprecated */ | |
322 | options.use_privileged_port = 0; | |
323 | break; | |
324 | case 'a': | |
325 | options.forward_agent = 0; | |
326 | break; | |
327 | case 'A': | |
328 | options.forward_agent = 1; | |
329 | break; | |
330 | case 'k': | |
331 | options.gss_deleg_creds = 0; | |
332 | break; | |
333 | case 'K': | |
334 | options.gss_authentication = 1; | |
335 | options.gss_deleg_creds = 1; | |
336 | break; | |
337 | case 'i': | |
338 | if (stat(optarg, &st) < 0) { | |
339 | fprintf(stderr, "Warning: Identity file %s " | |
340 | "not accessible: %s.\n", optarg, | |
341 | strerror(errno)); | |
342 | break; | |
343 | } | |
344 | if (options.num_identity_files >= | |
345 | SSH_MAX_IDENTITY_FILES) | |
346 | fatal("Too many identity files specified " | |
347 | "(max %d)", SSH_MAX_IDENTITY_FILES); | |
348 | options.identity_files[options.num_identity_files++] = | |
349 | xstrdup(optarg); | |
350 | break; | |
351 | case 'I': | |
352 | #ifdef SMARTCARD | |
353 | options.smartcard_device = xstrdup(optarg); | |
354 | #else | |
355 | fprintf(stderr, "no support for smartcards.\n"); | |
356 | #endif | |
357 | break; | |
358 | case 't': | |
359 | if (tty_flag) | |
360 | force_tty_flag = 1; | |
361 | tty_flag = 1; | |
362 | break; | |
363 | case 'v': | |
364 | if (debug_flag == 0) { | |
365 | debug_flag = 1; | |
366 | options.log_level = SYSLOG_LEVEL_DEBUG1; | |
367 | } else { | |
368 | if (options.log_level < SYSLOG_LEVEL_DEBUG3) | |
369 | options.log_level++; | |
370 | break; | |
371 | } | |
372 | /* FALLTHROUGH */ | |
373 | case 'V': | |
374 | fprintf(stderr, "%s, %s\n", | |
375 | SSH_RELEASE, SSLeay_version(SSLEAY_VERSION)); | |
376 | if (opt == 'V') | |
377 | exit(0); | |
378 | break; | |
379 | case 'w': | |
380 | if (options.tun_open == -1) | |
381 | options.tun_open = SSH_TUNMODE_DEFAULT; | |
382 | options.tun_local = a2tun(optarg, &options.tun_remote); | |
383 | if (options.tun_local == SSH_TUNID_ERR) { | |
384 | fprintf(stderr, | |
385 | "Bad tun device '%s'\n", optarg); | |
386 | exit(255); | |
387 | } | |
388 | break; | |
389 | case 'q': | |
390 | options.log_level = SYSLOG_LEVEL_QUIET; | |
391 | break; | |
392 | case 'e': | |
393 | if (optarg[0] == '^' && optarg[2] == 0 && | |
394 | (u_char) optarg[1] >= 64 && | |
395 | (u_char) optarg[1] < 128) | |
396 | options.escape_char = (u_char) optarg[1] & 31; | |
397 | else if (strlen(optarg) == 1) | |
398 | options.escape_char = (u_char) optarg[0]; | |
399 | else if (strcmp(optarg, "none") == 0) | |
400 | options.escape_char = SSH_ESCAPECHAR_NONE; | |
401 | else { | |
402 | fprintf(stderr, "Bad escape character '%s'.\n", | |
403 | optarg); | |
404 | exit(255); | |
405 | } | |
406 | break; | |
407 | case 'c': | |
408 | if (ciphers_valid(optarg)) { | |
409 | /* SSH2 only */ | |
410 | options.ciphers = xstrdup(optarg); | |
411 | options.cipher = SSH_CIPHER_INVALID; | |
412 | } else { | |
413 | /* SSH1 only */ | |
414 | options.cipher = cipher_number(optarg); | |
415 | if (options.cipher == -1) { | |
416 | fprintf(stderr, | |
417 | "Unknown cipher type '%s'\n", | |
418 | optarg); | |
419 | exit(255); | |
420 | } | |
421 | if (options.cipher == SSH_CIPHER_3DES) | |
422 | options.ciphers = "3des-cbc"; | |
423 | else if (options.cipher == SSH_CIPHER_BLOWFISH) | |
424 | options.ciphers = "blowfish-cbc"; | |
425 | else | |
426 | options.ciphers = (char *)-1; | |
427 | } | |
428 | break; | |
429 | case 'm': | |
430 | if (mac_valid(optarg)) | |
431 | options.macs = xstrdup(optarg); | |
432 | else { | |
433 | fprintf(stderr, "Unknown mac type '%s'\n", | |
434 | optarg); | |
435 | exit(255); | |
436 | } | |
437 | break; | |
438 | case 'M': | |
439 | if (options.control_master == SSHCTL_MASTER_YES) | |
440 | options.control_master = SSHCTL_MASTER_ASK; | |
441 | else | |
442 | options.control_master = SSHCTL_MASTER_YES; | |
443 | break; | |
444 | case 'p': | |
445 | options.port = a2port(optarg); | |
446 | if (options.port <= 0) { | |
447 | fprintf(stderr, "Bad port '%s'\n", optarg); | |
448 | exit(255); | |
449 | } | |
450 | break; | |
451 | case 'l': | |
452 | options.user = optarg; | |
453 | break; | |
454 | ||
455 | case 'L': | |
456 | if (parse_forward(&fwd, optarg, 0, 0)) | |
457 | add_local_forward(&options, &fwd); | |
458 | else { | |
459 | fprintf(stderr, | |
460 | "Bad local forwarding specification '%s'\n", | |
461 | optarg); | |
462 | exit(255); | |
463 | } | |
464 | break; | |
465 | ||
466 | case 'R': | |
467 | if (parse_forward(&fwd, optarg, 0, 1)) { | |
468 | add_remote_forward(&options, &fwd); | |
469 | } else { | |
470 | fprintf(stderr, | |
471 | "Bad remote forwarding specification " | |
472 | "'%s'\n", optarg); | |
473 | exit(255); | |
474 | } | |
475 | break; | |
476 | ||
477 | case 'D': | |
478 | if (parse_forward(&fwd, optarg, 1, 0)) { | |
479 | add_local_forward(&options, &fwd); | |
480 | } else { | |
481 | fprintf(stderr, | |
482 | "Bad dynamic forwarding specification " | |
483 | "'%s'\n", optarg); | |
484 | exit(255); | |
485 | } | |
486 | break; | |
487 | ||
488 | case 'C': | |
489 | options.compression = 1; | |
490 | break; | |
491 | case 'N': | |
492 | no_shell_flag = 1; | |
493 | no_tty_flag = 1; | |
494 | break; | |
495 | case 'o': | |
496 | dummy = 1; | |
497 | line = xstrdup(optarg); | |
498 | if (process_config_line(&options, host ? host : "", | |
499 | line, "command-line", 0, &dummy) != 0) | |
500 | exit(255); | |
501 | xfree(line); | |
502 | break; | |
503 | case 'T': | |
504 | no_tty_flag = 1; | |
505 | /* ensure that the user doesn't try to backdoor a */ | |
506 | /* null cipher switch on an interactive session */ | |
507 | /* so explicitly disable it no matter what */ | |
508 | options.none_switch=0; | |
509 | break; | |
510 | case 's': | |
511 | subsystem_flag = 1; | |
512 | break; | |
513 | case 'S': | |
514 | if (options.control_path != NULL) | |
515 | free(options.control_path); | |
516 | options.control_path = xstrdup(optarg); | |
517 | break; | |
518 | case 'b': | |
519 | options.bind_address = optarg; | |
520 | break; | |
521 | case 'F': | |
522 | config = optarg; | |
523 | break; | |
524 | default: | |
525 | usage(); | |
526 | } | |
527 | } | |
528 | ||
529 | ac -= optind; | |
530 | av += optind; | |
531 | ||
532 | if (ac > 0 && !host && **av != '-') { | |
533 | if (strrchr(*av, '@')) { | |
534 | p = xstrdup(*av); | |
535 | cp = strrchr(p, '@'); | |
536 | if (cp == NULL || cp == p) | |
537 | usage(); | |
538 | options.user = p; | |
539 | *cp = '\0'; | |
540 | host = ++cp; | |
541 | } else | |
542 | host = *av; | |
543 | if (ac > 1) { | |
544 | optind = optreset = 1; | |
545 | goto again; | |
546 | } | |
547 | ac--, av++; | |
548 | } | |
549 | ||
550 | /* Check that we got a host name. */ | |
551 | if (!host) | |
552 | usage(); | |
553 | ||
554 | SSLeay_add_all_algorithms(); | |
555 | ERR_load_crypto_strings(); | |
556 | ||
557 | /* Initialize the command to execute on remote host. */ | |
558 | buffer_init(&command); | |
559 | ||
560 | /* | |
561 | * Save the command to execute on the remote host in a buffer. There | |
562 | * is no limit on the length of the command, except by the maximum | |
563 | * packet size. Also sets the tty flag if there is no command. | |
564 | */ | |
565 | if (!ac) { | |
566 | /* No command specified - execute shell on a tty. */ | |
567 | tty_flag = 1; | |
568 | if (subsystem_flag) { | |
569 | fprintf(stderr, | |
570 | "You must specify a subsystem to invoke.\n"); | |
571 | usage(); | |
572 | } | |
573 | } else { | |
574 | /* A command has been specified. Store it into the buffer. */ | |
575 | for (i = 0; i < ac; i++) { | |
576 | if (i) | |
577 | buffer_append(&command, " ", 1); | |
578 | buffer_append(&command, av[i], strlen(av[i])); | |
579 | } | |
580 | } | |
581 | ||
582 | /* Cannot fork to background if no command. */ | |
583 | if (fork_after_authentication_flag && buffer_len(&command) == 0 && | |
584 | !no_shell_flag) | |
585 | fatal("Cannot fork into background without a command " | |
586 | "to execute."); | |
587 | ||
588 | /* Allocate a tty by default if no command specified. */ | |
589 | if (buffer_len(&command) == 0) | |
590 | tty_flag = 1; | |
591 | ||
592 | /* Force no tty */ | |
593 | if (no_tty_flag) | |
594 | tty_flag = 0; | |
595 | /* Do not allocate a tty if stdin is not a tty. */ | |
596 | if ((!isatty(fileno(stdin)) || stdin_null_flag) && !force_tty_flag) { | |
597 | if (tty_flag) | |
598 | logit("Pseudo-terminal will not be allocated because " | |
599 | "stdin is not a terminal."); | |
600 | tty_flag = 0; | |
601 | } | |
602 | ||
603 | /* | |
604 | * Initialize "log" output. Since we are the client all output | |
605 | * actually goes to stderr. | |
606 | */ | |
607 | log_init(av[0], | |
608 | options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level, | |
609 | SYSLOG_FACILITY_USER, !use_syslog); | |
610 | ||
611 | /* | |
612 | * Read per-user configuration file. Ignore the system wide config | |
613 | * file if the user specifies a config file on the command line. | |
614 | */ | |
615 | if (config != NULL) { | |
616 | if (!read_config_file(config, host, &options, 0)) | |
617 | fatal("Can't open user config file %.100s: " | |
618 | "%.100s", config, strerror(errno)); | |
619 | } else { | |
620 | /* | |
621 | * Since the config file parsing code aborts if it sees | |
622 | * options it doesn't recognize, allow users to put | |
623 | * options specific to compile-time add-ons in alternate | |
624 | * config files so their primary config file will | |
625 | * interoperate SSH versions that don't support those | |
626 | * options. | |
627 | */ | |
628 | #ifdef GSSAPI | |
629 | snprintf(buf, sizeof buf, "%.100s/%.100s.gssapi", pw->pw_dir, | |
630 | _PATH_SSH_USER_CONFFILE); | |
631 | (void)read_config_file(buf, host, &options, 1); | |
632 | #ifdef GSI | |
633 | snprintf(buf, sizeof buf, "%.100s/%.100s.gsi", pw->pw_dir, | |
634 | _PATH_SSH_USER_CONFFILE); | |
635 | (void)read_config_file(buf, host, &options, 1); | |
636 | #endif | |
637 | #if defined(KRB5) | |
638 | snprintf(buf, sizeof buf, "%.100s/%.100s.krb", pw->pw_dir, | |
639 | _PATH_SSH_USER_CONFFILE); | |
640 | (void)read_config_file(buf, host, &options, 1); | |
641 | #endif | |
642 | #endif | |
643 | snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, | |
644 | _PATH_SSH_USER_CONFFILE); | |
645 | (void)read_config_file(buf, host, &options, 1); | |
646 | ||
647 | /* Read systemwide configuration file after use config. */ | |
648 | (void)read_config_file(_PATH_HOST_CONFIG_FILE, host, | |
649 | &options, 0); | |
650 | } | |
651 | ||
652 | /* Fill configuration defaults. */ | |
653 | fill_default_options(&options); | |
654 | ||
655 | channel_set_af(options.address_family); | |
656 | ||
657 | /* reinit */ | |
658 | log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, !use_syslog); | |
659 | ||
660 | seed_rng(); | |
661 | ||
662 | if (options.user == NULL) { | |
663 | options.user = xstrdup(pw->pw_name); | |
664 | options.implicit = 1; | |
665 | } | |
666 | else options.implicit = 0; | |
667 | ||
668 | /* Get default port if port has not been set. */ | |
669 | if (options.port == 0) { | |
670 | sp = getservbyname(SSH_SERVICE_NAME, "tcp"); | |
671 | options.port = sp ? ntohs(sp->s_port) : SSH_DEFAULT_PORT; | |
672 | } | |
673 | ||
674 | if (options.local_command != NULL) { | |
675 | char thishost[NI_MAXHOST]; | |
676 | ||
677 | if (gethostname(thishost, sizeof(thishost)) == -1) | |
678 | fatal("gethostname: %s", strerror(errno)); | |
679 | snprintf(buf, sizeof(buf), "%d", options.port); | |
680 | debug3("expanding LocalCommand: %s", options.local_command); | |
681 | cp = options.local_command; | |
682 | options.local_command = percent_expand(cp, "d", pw->pw_dir, | |
683 | "h", options.hostname? options.hostname : host, | |
684 | "l", thishost, "n", host, "r", options.user, "p", buf, | |
685 | "u", pw->pw_name, (char *)NULL); | |
686 | debug3("expanded LocalCommand: %s", options.local_command); | |
687 | xfree(cp); | |
688 | } | |
689 | ||
690 | if (options.hostname != NULL) | |
691 | host = options.hostname; | |
692 | ||
693 | /* force lowercase for hostkey matching */ | |
694 | if (options.host_key_alias != NULL) { | |
695 | for (p = options.host_key_alias; *p; p++) | |
696 | if (isupper(*p)) | |
697 | *p = (char)tolower(*p); | |
698 | } | |
699 | ||
700 | if (options.proxy_command != NULL && | |
701 | strcmp(options.proxy_command, "none") == 0) { | |
702 | xfree(options.proxy_command); | |
703 | options.proxy_command = NULL; | |
704 | } | |
705 | if (options.control_path != NULL && | |
706 | strcmp(options.control_path, "none") == 0) { | |
707 | xfree(options.control_path); | |
708 | options.control_path = NULL; | |
709 | } | |
710 | ||
711 | if (options.control_path != NULL) { | |
712 | char thishost[NI_MAXHOST]; | |
713 | ||
714 | if (gethostname(thishost, sizeof(thishost)) == -1) | |
715 | fatal("gethostname: %s", strerror(errno)); | |
716 | snprintf(buf, sizeof(buf), "%d", options.port); | |
717 | cp = tilde_expand_filename(options.control_path, | |
718 | original_real_uid); | |
719 | xfree(options.control_path); | |
720 | options.control_path = percent_expand(cp, "p", buf, "h", host, | |
721 | "r", options.user, "l", thishost, (char *)NULL); | |
722 | xfree(cp); | |
723 | } | |
724 | if (muxclient_command != 0 && options.control_path == NULL) | |
725 | fatal("No ControlPath specified for \"-O\" command"); | |
726 | if (options.control_path != NULL) | |
727 | muxclient(options.control_path); | |
728 | ||
729 | timeout_ms = options.connection_timeout * 1000; | |
730 | ||
731 | /* Open a connection to the remote host. */ | |
732 | if (ssh_connect(host, &hostaddr, options.port, | |
733 | options.address_family, options.connection_attempts, &timeout_ms, | |
734 | options.tcp_keep_alive, | |
735 | #ifdef HAVE_CYGWIN | |
736 | options.use_privileged_port, | |
737 | #else | |
738 | original_effective_uid == 0 && options.use_privileged_port, | |
739 | #endif | |
740 | options.proxy_command) != 0) | |
741 | exit(255); | |
742 | ||
743 | if (timeout_ms > 0) | |
744 | debug3("timeout: %d ms remain after connect", timeout_ms); | |
745 | ||
746 | /* | |
747 | * If we successfully made the connection, load the host private key | |
748 | * in case we will need it later for combined rsa-rhosts | |
749 | * authentication. This must be done before releasing extra | |
750 | * privileges, because the file is only readable by root. | |
751 | * If we cannot access the private keys, load the public keys | |
752 | * instead and try to execute the ssh-keysign helper instead. | |
753 | */ | |
754 | sensitive_data.nkeys = 0; | |
755 | sensitive_data.keys = NULL; | |
756 | sensitive_data.external_keysign = 0; | |
757 | if (options.rhosts_rsa_authentication || | |
758 | options.hostbased_authentication) { | |
759 | sensitive_data.nkeys = 3; | |
760 | sensitive_data.keys = xcalloc(sensitive_data.nkeys, | |
761 | sizeof(Key)); | |
762 | ||
763 | PRIV_START; | |
764 | sensitive_data.keys[0] = key_load_private_type(KEY_RSA1, | |
765 | _PATH_HOST_KEY_FILE, "", NULL, NULL); | |
766 | sensitive_data.keys[1] = key_load_private_type(KEY_DSA, | |
767 | _PATH_HOST_DSA_KEY_FILE, "", NULL, NULL); | |
768 | sensitive_data.keys[2] = key_load_private_type(KEY_RSA, | |
769 | _PATH_HOST_RSA_KEY_FILE, "", NULL, NULL); | |
770 | PRIV_END; | |
771 | ||
772 | if (options.hostbased_authentication == 1 && | |
773 | sensitive_data.keys[0] == NULL && | |
774 | sensitive_data.keys[1] == NULL && | |
775 | sensitive_data.keys[2] == NULL) { | |
776 | sensitive_data.keys[1] = key_load_public( | |
777 | _PATH_HOST_DSA_KEY_FILE, NULL); | |
778 | sensitive_data.keys[2] = key_load_public( | |
779 | _PATH_HOST_RSA_KEY_FILE, NULL); | |
780 | sensitive_data.external_keysign = 1; | |
781 | } | |
782 | } | |
783 | /* | |
784 | * Get rid of any extra privileges that we may have. We will no | |
785 | * longer need them. Also, extra privileges could make it very hard | |
786 | * to read identity files and other non-world-readable files from the | |
787 | * user's home directory if it happens to be on a NFS volume where | |
788 | * root is mapped to nobody. | |
789 | */ | |
790 | if (original_effective_uid == 0) { | |
791 | PRIV_START; | |
792 | permanently_set_uid(pw); | |
793 | } | |
794 | ||
795 | /* | |
796 | * Now that we are back to our own permissions, create ~/.ssh | |
797 | * directory if it doesn't already exist. | |
798 | */ | |
799 | snprintf(buf, sizeof buf, "%.100s%s%.100s", pw->pw_dir, | |
800 | strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR); | |
801 | if (stat(buf, &st) < 0) | |
802 | if (mkdir(buf, 0700) < 0) | |
803 | error("Could not create directory '%.200s'.", buf); | |
804 | ||
805 | /* load options.identity_files */ | |
806 | load_public_identity_files(); | |
807 | ||
808 | /* Expand ~ in known host file names. */ | |
809 | /* XXX mem-leaks: */ | |
810 | options.system_hostfile = | |
811 | tilde_expand_filename(options.system_hostfile, original_real_uid); | |
812 | options.user_hostfile = | |
813 | tilde_expand_filename(options.user_hostfile, original_real_uid); | |
814 | options.system_hostfile2 = | |
815 | tilde_expand_filename(options.system_hostfile2, original_real_uid); | |
816 | options.user_hostfile2 = | |
817 | tilde_expand_filename(options.user_hostfile2, original_real_uid); | |
818 | ||
819 | signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */ | |
820 | ||
821 | /* Log into the remote system. Never returns if the login fails. */ | |
822 | ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr, | |
823 | pw, timeout_ms); | |
824 | ||
825 | /* We no longer need the private host keys. Clear them now. */ | |
826 | if (sensitive_data.nkeys != 0) { | |
827 | for (i = 0; i < sensitive_data.nkeys; i++) { | |
828 | if (sensitive_data.keys[i] != NULL) { | |
829 | /* Destroys contents safely */ | |
830 | debug3("clear hostkey %d", i); | |
831 | key_free(sensitive_data.keys[i]); | |
832 | sensitive_data.keys[i] = NULL; | |
833 | } | |
834 | } | |
835 | xfree(sensitive_data.keys); | |
836 | } | |
837 | for (i = 0; i < options.num_identity_files; i++) { | |
838 | if (options.identity_files[i]) { | |
839 | xfree(options.identity_files[i]); | |
840 | options.identity_files[i] = NULL; | |
841 | } | |
842 | if (options.identity_keys[i]) { | |
843 | key_free(options.identity_keys[i]); | |
844 | options.identity_keys[i] = NULL; | |
845 | } | |
846 | } | |
847 | ||
848 | exit_status = compat20 ? ssh_session2() : ssh_session(); | |
849 | packet_close(); | |
850 | ||
851 | if (options.control_path != NULL && muxserver_sock != -1) | |
852 | unlink(options.control_path); | |
853 | ||
854 | /* | |
855 | * Send SIGHUP to proxy command if used. We don't wait() in | |
856 | * case it hangs and instead rely on init to reap the child | |
857 | */ | |
858 | if (proxy_command_pid > 1) | |
859 | kill(proxy_command_pid, SIGHUP); | |
860 | ||
861 | return exit_status; | |
862 | } | |
863 | ||
864 | /* Callback for remote forward global requests */ | |
865 | static void | |
866 | ssh_confirm_remote_forward(int type, u_int32_t seq, void *ctxt) | |
867 | { | |
868 | Forward *rfwd = (Forward *)ctxt; | |
869 | ||
870 | /* XXX verbose() on failure? */ | |
871 | debug("remote forward %s for: listen %d, connect %s:%d", | |
872 | type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure", | |
873 | rfwd->listen_port, rfwd->connect_host, rfwd->connect_port); | |
874 | if (type == SSH2_MSG_REQUEST_SUCCESS && rfwd->listen_port == 0) { | |
875 | logit("Allocated port %u for remote forward to %s:%d", | |
876 | packet_get_int(), | |
877 | rfwd->connect_host, rfwd->connect_port); | |
878 | } | |
879 | ||
880 | if (type == SSH2_MSG_REQUEST_FAILURE) { | |
881 | if (options.exit_on_forward_failure) | |
882 | fatal("Error: remote port forwarding failed for " | |
883 | "listen port %d", rfwd->listen_port); | |
884 | else | |
885 | logit("Warning: remote port forwarding failed for " | |
886 | "listen port %d", rfwd->listen_port); | |
887 | } | |
888 | if (++remote_forward_confirms_received == options.num_remote_forwards) { | |
889 | debug("All remote forwarding requests processed"); | |
890 | if (fork_after_authentication_flag) { | |
891 | fork_after_authentication_flag = 0; | |
892 | if (daemon(1, 1) < 0) | |
893 | fatal("daemon() failed: %.200s", | |
894 | strerror(errno)); | |
895 | } | |
896 | } | |
897 | } | |
898 | ||
899 | static void | |
900 | ssh_init_forwarding(void) | |
901 | { | |
902 | int success = 0; | |
903 | int i; | |
904 | ||
905 | /* Initiate local TCP/IP port forwardings. */ | |
906 | for (i = 0; i < options.num_local_forwards; i++) { | |
907 | debug("Local connections to %.200s:%d forwarded to remote " | |
908 | "address %.200s:%d", | |
909 | (options.local_forwards[i].listen_host == NULL) ? | |
910 | (options.gateway_ports ? "*" : "LOCALHOST") : | |
911 | options.local_forwards[i].listen_host, | |
912 | options.local_forwards[i].listen_port, | |
913 | options.local_forwards[i].connect_host, | |
914 | options.local_forwards[i].connect_port); | |
915 | success += channel_setup_local_fwd_listener( | |
916 | options.local_forwards[i].listen_host, | |
917 | options.local_forwards[i].listen_port, | |
918 | options.local_forwards[i].connect_host, | |
919 | options.local_forwards[i].connect_port, | |
920 | options.gateway_ports); | |
921 | } | |
922 | if (i > 0 && success != i && options.exit_on_forward_failure) | |
923 | fatal("Could not request local forwarding."); | |
924 | if (i > 0 && success == 0) | |
925 | error("Could not request local forwarding."); | |
926 | ||
927 | /* Initiate remote TCP/IP port forwardings. */ | |
928 | for (i = 0; i < options.num_remote_forwards; i++) { | |
929 | debug("Remote connections from %.200s:%d forwarded to " | |
930 | "local address %.200s:%d", | |
931 | (options.remote_forwards[i].listen_host == NULL) ? | |
932 | "LOCALHOST" : options.remote_forwards[i].listen_host, | |
933 | options.remote_forwards[i].listen_port, | |
934 | options.remote_forwards[i].connect_host, | |
935 | options.remote_forwards[i].connect_port); | |
936 | if (channel_request_remote_forwarding( | |
937 | options.remote_forwards[i].listen_host, | |
938 | options.remote_forwards[i].listen_port, | |
939 | options.remote_forwards[i].connect_host, | |
940 | options.remote_forwards[i].connect_port) < 0) { | |
941 | if (options.exit_on_forward_failure) | |
942 | fatal("Could not request remote forwarding."); | |
943 | else | |
944 | logit("Warning: Could not request remote " | |
945 | "forwarding."); | |
946 | } | |
947 | client_register_global_confirm(ssh_confirm_remote_forward, | |
948 | &options.remote_forwards[i]); | |
949 | } | |
950 | ||
951 | /* Initiate tunnel forwarding. */ | |
952 | if (options.tun_open != SSH_TUNMODE_NO) { | |
953 | if (client_request_tun_fwd(options.tun_open, | |
954 | options.tun_local, options.tun_remote) == -1) { | |
955 | if (options.exit_on_forward_failure) | |
956 | fatal("Could not request tunnel forwarding."); | |
957 | else | |
958 | error("Could not request tunnel forwarding."); | |
959 | } | |
960 | } | |
961 | } | |
962 | ||
963 | static void | |
964 | check_agent_present(void) | |
965 | { | |
966 | if (options.forward_agent) { | |
967 | /* Clear agent forwarding if we don't have an agent. */ | |
968 | if (!ssh_agent_present()) | |
969 | options.forward_agent = 0; | |
970 | } | |
971 | } | |
972 | ||
973 | static int | |
974 | ssh_session(void) | |
975 | { | |
976 | int type; | |
977 | int interactive = 0; | |
978 | int have_tty = 0; | |
979 | struct winsize ws; | |
980 | char *cp; | |
981 | const char *display; | |
982 | ||
983 | /* Enable compression if requested. */ | |
984 | if (options.compression) { | |
985 | debug("Requesting compression at level %d.", | |
986 | options.compression_level); | |
987 | ||
988 | if (options.compression_level < 1 || | |
989 | options.compression_level > 9) | |
990 | fatal("Compression level must be from 1 (fast) to " | |
991 | "9 (slow, best)."); | |
992 | ||
993 | /* Send the request. */ | |
994 | packet_start(SSH_CMSG_REQUEST_COMPRESSION); | |
995 | packet_put_int(options.compression_level); | |
996 | packet_send(); | |
997 | packet_write_wait(); | |
998 | type = packet_read(); | |
999 | if (type == SSH_SMSG_SUCCESS) | |
1000 | packet_start_compression(options.compression_level); | |
1001 | else if (type == SSH_SMSG_FAILURE) | |
1002 | logit("Warning: Remote host refused compression."); | |
1003 | else | |
1004 | packet_disconnect("Protocol error waiting for " | |
1005 | "compression response."); | |
1006 | } | |
1007 | /* Allocate a pseudo tty if appropriate. */ | |
1008 | if (tty_flag) { | |
1009 | debug("Requesting pty."); | |
1010 | ||
1011 | /* Start the packet. */ | |
1012 | packet_start(SSH_CMSG_REQUEST_PTY); | |
1013 | ||
1014 | /* Store TERM in the packet. There is no limit on the | |
1015 | length of the string. */ | |
1016 | cp = getenv("TERM"); | |
1017 | if (!cp) | |
1018 | cp = ""; | |
1019 | packet_put_cstring(cp); | |
1020 | ||
1021 | /* Store window size in the packet. */ | |
1022 | if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0) | |
1023 | memset(&ws, 0, sizeof(ws)); | |
1024 | packet_put_int((u_int)ws.ws_row); | |
1025 | packet_put_int((u_int)ws.ws_col); | |
1026 | packet_put_int((u_int)ws.ws_xpixel); | |
1027 | packet_put_int((u_int)ws.ws_ypixel); | |
1028 | ||
1029 | /* Store tty modes in the packet. */ | |
1030 | tty_make_modes(fileno(stdin), NULL); | |
1031 | ||
1032 | /* Send the packet, and wait for it to leave. */ | |
1033 | packet_send(); | |
1034 | packet_write_wait(); | |
1035 | ||
1036 | /* Read response from the server. */ | |
1037 | type = packet_read(); | |
1038 | if (type == SSH_SMSG_SUCCESS) { | |
1039 | interactive = 1; | |
1040 | have_tty = 1; | |
1041 | } else if (type == SSH_SMSG_FAILURE) | |
1042 | logit("Warning: Remote host failed or refused to " | |
1043 | "allocate a pseudo tty."); | |
1044 | else | |
1045 | packet_disconnect("Protocol error waiting for pty " | |
1046 | "request response."); | |
1047 | } | |
1048 | /* Request X11 forwarding if enabled and DISPLAY is set. */ | |
1049 | display = getenv("DISPLAY"); | |
1050 | if (options.forward_x11 && display != NULL) { | |
1051 | char *proto, *data; | |
1052 | /* Get reasonable local authentication information. */ | |
1053 | client_x11_get_proto(display, options.xauth_location, | |
1054 | options.forward_x11_trusted, &proto, &data); | |
1055 | /* Request forwarding with authentication spoofing. */ | |
1056 | debug("Requesting X11 forwarding with authentication " | |
1057 | "spoofing."); | |
1058 | x11_request_forwarding_with_spoofing(0, display, proto, data); | |
1059 | ||
1060 | /* Read response from the server. */ | |
1061 | type = packet_read(); | |
1062 | if (type == SSH_SMSG_SUCCESS) { | |
1063 | interactive = 1; | |
1064 | } else if (type == SSH_SMSG_FAILURE) { | |
1065 | logit("Warning: Remote host denied X11 forwarding."); | |
1066 | } else { | |
1067 | packet_disconnect("Protocol error waiting for X11 " | |
1068 | "forwarding"); | |
1069 | } | |
1070 | } | |
1071 | /* Tell the packet module whether this is an interactive session. */ | |
1072 | packet_set_interactive(interactive); | |
1073 | ||
1074 | /* Request authentication agent forwarding if appropriate. */ | |
1075 | check_agent_present(); | |
1076 | ||
1077 | if (options.forward_agent) { | |
1078 | debug("Requesting authentication agent forwarding."); | |
1079 | auth_request_forwarding(); | |
1080 | ||
1081 | /* Read response from the server. */ | |
1082 | type = packet_read(); | |
1083 | packet_check_eom(); | |
1084 | if (type != SSH_SMSG_SUCCESS) | |
1085 | logit("Warning: Remote host denied authentication agent forwarding."); | |
1086 | } | |
1087 | ||
1088 | /* Initiate port forwardings. */ | |
1089 | ssh_init_forwarding(); | |
1090 | ||
1091 | /* Execute a local command */ | |
1092 | if (options.local_command != NULL && | |
1093 | options.permit_local_command) | |
1094 | ssh_local_cmd(options.local_command); | |
1095 | ||
1096 | /* | |
1097 | * If requested and we are not interested in replies to remote | |
1098 | * forwarding requests, then let ssh continue in the background. | |
1099 | */ | |
1100 | if (fork_after_authentication_flag && | |
1101 | (!options.exit_on_forward_failure || | |
1102 | options.num_remote_forwards == 0)) { | |
1103 | fork_after_authentication_flag = 0; | |
1104 | if (daemon(1, 1) < 0) | |
1105 | fatal("daemon() failed: %.200s", strerror(errno)); | |
1106 | } | |
1107 | ||
1108 | /* | |
1109 | * If a command was specified on the command line, execute the | |
1110 | * command now. Otherwise request the server to start a shell. | |
1111 | */ | |
1112 | if (buffer_len(&command) > 0) { | |
1113 | int len = buffer_len(&command); | |
1114 | if (len > 900) | |
1115 | len = 900; | |
1116 | debug("Sending command: %.*s", len, | |
1117 | (u_char *)buffer_ptr(&command)); | |
1118 | packet_start(SSH_CMSG_EXEC_CMD); | |
1119 | packet_put_string(buffer_ptr(&command), buffer_len(&command)); | |
1120 | packet_send(); | |
1121 | packet_write_wait(); | |
1122 | } else { | |
1123 | debug("Requesting shell."); | |
1124 | packet_start(SSH_CMSG_EXEC_SHELL); | |
1125 | packet_send(); | |
1126 | packet_write_wait(); | |
1127 | } | |
1128 | ||
1129 | /* Enter the interactive session. */ | |
1130 | return client_loop(have_tty, tty_flag ? | |
1131 | options.escape_char : SSH_ESCAPECHAR_NONE, 0); | |
1132 | } | |
1133 | ||
1134 | /* request pty/x11/agent/tcpfwd/shell for channel */ | |
1135 | static void | |
1136 | ssh_session2_setup(int id, void *arg) | |
1137 | { | |
1138 | extern char **environ; | |
1139 | const char *display; | |
1140 | int interactive = tty_flag; | |
1141 | ||
1142 | display = getenv("DISPLAY"); | |
1143 | if (options.forward_x11 && display != NULL) { | |
1144 | char *proto, *data; | |
1145 | /* Get reasonable local authentication information. */ | |
1146 | client_x11_get_proto(display, options.xauth_location, | |
1147 | options.forward_x11_trusted, &proto, &data); | |
1148 | /* Request forwarding with authentication spoofing. */ | |
1149 | debug("Requesting X11 forwarding with authentication " | |
1150 | "spoofing."); | |
1151 | x11_request_forwarding_with_spoofing(id, display, proto, data); | |
1152 | interactive = 1; | |
1153 | /* XXX wait for reply */ | |
1154 | } | |
1155 | ||
1156 | check_agent_present(); | |
1157 | if (options.forward_agent) { | |
1158 | debug("Requesting authentication agent forwarding."); | |
1159 | channel_request_start(id, "auth-agent-req@openssh.com", 0); | |
1160 | packet_send(); | |
1161 | } | |
1162 | ||
1163 | client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"), | |
1164 | NULL, fileno(stdin), &command, environ); | |
1165 | ||
1166 | packet_set_interactive(interactive); | |
1167 | } | |
1168 | ||
1169 | /* open new channel for a session */ | |
1170 | static int | |
1171 | ssh_session2_open(void) | |
1172 | { | |
1173 | Channel *c; | |
1174 | int window, packetmax, in, out, err; | |
1175 | int sock; | |
1176 | int socksize; | |
1177 | int socksizelen = sizeof(int); | |
1178 | ||
1179 | if (stdin_null_flag) { | |
1180 | in = open(_PATH_DEVNULL, O_RDONLY); | |
1181 | } else { | |
1182 | in = dup(STDIN_FILENO); | |
1183 | } | |
1184 | out = dup(STDOUT_FILENO); | |
1185 | err = dup(STDERR_FILENO); | |
1186 | ||
1187 | if (in < 0 || out < 0 || err < 0) | |
1188 | fatal("dup() in/out/err failed"); | |
1189 | ||
1190 | /* enable nonblocking unless tty */ | |
1191 | if (!isatty(in)) | |
1192 | set_nonblock(in); | |
1193 | if (!isatty(out)) | |
1194 | set_nonblock(out); | |
1195 | if (!isatty(err)) | |
1196 | set_nonblock(err); | |
1197 | ||
1198 | /* we need to check to see if what they want to do about buffer */ | |
1199 | /* sizes here. In a hpn to nonhpn connection we want to limit */ | |
1200 | /* the window size to something reasonable in case the far side */ | |
1201 | /* has the large window bug. In hpn to hpn connection we want to */ | |
1202 | /* use the max window size but allow the user to override it */ | |
1203 | /* lastly if they disabled hpn then use the ssh std window size */ | |
1204 | ||
1205 | /* so why don't we just do a getsockopt() here and set the */ | |
1206 | /* ssh window to that? In the case of a autotuning receive */ | |
1207 | /* window the window would get stuck at the initial buffer */ | |
1208 | /* size generally less than 96k. Therefore we need to set the */ | |
1209 | /* maximum ssh window size to the maximum hpn buffer size */ | |
1210 | /* unless the user has specifically set the tcprcvbufpoll */ | |
1211 | /* to no. In which case we *can* just set the window to the */ | |
1212 | /* minimum of the hpn buffer size and tcp receive buffer size */ | |
1213 | ||
1214 | if (tty_flag) | |
1215 | options.hpn_buffer_size = CHAN_SES_WINDOW_DEFAULT; | |
1216 | else | |
1217 | options.hpn_buffer_size = 2*1024*1024; | |
1218 | ||
1219 | if (datafellows & SSH_BUG_LARGEWINDOW) | |
1220 | { | |
1221 | debug("HPN to Non-HPN Connection"); | |
1222 | } | |
1223 | else | |
1224 | { | |
1225 | if (options.tcp_rcv_buf_poll <= 0) | |
1226 | { | |
1227 | sock = socket(AF_INET, SOCK_STREAM, 0); | |
1228 | getsockopt(sock, SOL_SOCKET, SO_RCVBUF, | |
1229 | &socksize, &socksizelen); | |
1230 | close(sock); | |
1231 | debug("socksize %d", socksize); | |
1232 | options.hpn_buffer_size = socksize; | |
1233 | debug ("HPNBufferSize set to TCP RWIN: %d", options.hpn_buffer_size); | |
1234 | } | |
1235 | else | |
1236 | { | |
1237 | if (options.tcp_rcv_buf > 0) | |
1238 | { | |
1239 | /*create a socket but don't connect it */ | |
1240 | /* we use that the get the rcv socket size */ | |
1241 | sock = socket(AF_INET, SOCK_STREAM, 0); | |
1242 | /* if they are using the tcp_rcv_buf option */ | |
1243 | /* attempt to set the buffer size to that */ | |
1244 | if (options.tcp_rcv_buf) | |
1245 | setsockopt(sock, SOL_SOCKET, SO_RCVBUF, (void *)&options.tcp_rcv_buf, | |
1246 | sizeof(options.tcp_rcv_buf)); | |
1247 | getsockopt(sock, SOL_SOCKET, SO_RCVBUF, | |
1248 | &socksize, &socksizelen); | |
1249 | close(sock); | |
1250 | debug("socksize %d", socksize); | |
1251 | options.hpn_buffer_size = socksize; | |
1252 | debug ("HPNBufferSize set to user TCPRcvBuf: %d", options.hpn_buffer_size); | |
1253 | } | |
1254 | } | |
1255 | ||
1256 | } | |
1257 | ||
1258 | debug("Final hpn_buffer_size = %d", options.hpn_buffer_size); | |
1259 | ||
1260 | window = options.hpn_buffer_size; | |
1261 | ||
1262 | channel_set_hpn(options.hpn_disabled, options.hpn_buffer_size); | |
1263 | ||
1264 | packetmax = CHAN_SES_PACKET_DEFAULT; | |
1265 | if (tty_flag) { | |
1266 | window = 4*CHAN_SES_PACKET_DEFAULT; | |
1267 | window >>= 1; | |
1268 | packetmax >>= 1; | |
1269 | } | |
1270 | c = channel_new( | |
1271 | "session", SSH_CHANNEL_OPENING, in, out, err, | |
1272 | window, packetmax, CHAN_EXTENDED_WRITE, | |
1273 | "client-session", /*nonblock*/0); | |
1274 | if ((options.tcp_rcv_buf_poll > 0) && (!options.hpn_disabled)) { | |
1275 | c->dynamic_window = 1; | |
1276 | debug ("Enabled Dynamic Window Scaling\n"); | |
1277 | } | |
1278 | debug3("ssh_session2_open: channel_new: %d", c->self); | |
1279 | ||
1280 | channel_send_open(c->self); | |
1281 | if (!no_shell_flag) | |
1282 | channel_register_open_confirm(c->self, | |
1283 | ssh_session2_setup, NULL); | |
1284 | ||
1285 | return c->self; | |
1286 | } | |
1287 | ||
1288 | static int | |
1289 | ssh_session2(void) | |
1290 | { | |
1291 | int id = -1; | |
1292 | ||
1293 | /* XXX should be pre-session */ | |
1294 | ssh_init_forwarding(); | |
1295 | ||
1296 | if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN)) | |
1297 | id = ssh_session2_open(); | |
1298 | ||
1299 | /* If we don't expect to open a new session, then disallow it */ | |
1300 | if (options.control_master == SSHCTL_MASTER_NO && | |
1301 | (datafellows & SSH_NEW_OPENSSH)) { | |
1302 | debug("Requesting no-more-sessions@openssh.com"); | |
1303 | packet_start(SSH2_MSG_GLOBAL_REQUEST); | |
1304 | packet_put_cstring("no-more-sessions@openssh.com"); | |
1305 | packet_put_char(0); | |
1306 | packet_send(); | |
1307 | } | |
1308 | ||
1309 | /* Execute a local command */ | |
1310 | if (options.local_command != NULL && | |
1311 | options.permit_local_command) | |
1312 | ssh_local_cmd(options.local_command); | |
1313 | ||
1314 | /* Start listening for multiplex clients */ | |
1315 | muxserver_listen(); | |
1316 | ||
1317 | /* If requested, let ssh continue in the background. */ | |
1318 | if (fork_after_authentication_flag) { | |
1319 | fork_after_authentication_flag = 0; | |
1320 | if (daemon(1, 1) < 0) | |
1321 | fatal("daemon() failed: %.200s", strerror(errno)); | |
1322 | } | |
1323 | ||
1324 | return client_loop(tty_flag, tty_flag ? | |
1325 | options.escape_char : SSH_ESCAPECHAR_NONE, id); | |
1326 | } | |
1327 | ||
1328 | static void | |
1329 | load_public_identity_files(void) | |
1330 | { | |
1331 | char *filename, *cp, thishost[NI_MAXHOST]; | |
1332 | char *pwdir = NULL, *pwname = NULL; | |
1333 | int i = 0; | |
1334 | Key *public; | |
1335 | struct passwd *pw; | |
1336 | #ifdef SMARTCARD | |
1337 | Key **keys; | |
1338 | ||
1339 | if (options.smartcard_device != NULL && | |
1340 | options.num_identity_files < SSH_MAX_IDENTITY_FILES && | |
1341 | (keys = sc_get_keys(options.smartcard_device, NULL)) != NULL) { | |
1342 | int count = 0; | |
1343 | for (i = 0; keys[i] != NULL; i++) { | |
1344 | count++; | |
1345 | memmove(&options.identity_files[1], | |
1346 | &options.identity_files[0], | |
1347 | sizeof(char *) * (SSH_MAX_IDENTITY_FILES - 1)); | |
1348 | memmove(&options.identity_keys[1], | |
1349 | &options.identity_keys[0], | |
1350 | sizeof(Key *) * (SSH_MAX_IDENTITY_FILES - 1)); | |
1351 | options.num_identity_files++; | |
1352 | options.identity_keys[0] = keys[i]; | |
1353 | options.identity_files[0] = sc_get_key_label(keys[i]); | |
1354 | } | |
1355 | if (options.num_identity_files > SSH_MAX_IDENTITY_FILES) | |
1356 | options.num_identity_files = SSH_MAX_IDENTITY_FILES; | |
1357 | i = count; | |
1358 | xfree(keys); | |
1359 | } | |
1360 | #endif /* SMARTCARD */ | |
1361 | if ((pw = getpwuid(original_real_uid)) == NULL) | |
1362 | fatal("load_public_identity_files: getpwuid failed"); | |
1363 | pwname = xstrdup(pw->pw_name); | |
1364 | pwdir = xstrdup(pw->pw_dir); | |
1365 | if (gethostname(thishost, sizeof(thishost)) == -1) | |
1366 | fatal("load_public_identity_files: gethostname: %s", | |
1367 | strerror(errno)); | |
1368 | for (; i < options.num_identity_files; i++) { | |
1369 | cp = tilde_expand_filename(options.identity_files[i], | |
1370 | original_real_uid); | |
1371 | filename = percent_expand(cp, "d", pwdir, | |
1372 | "u", pwname, "l", thishost, "h", host, | |
1373 | "r", options.user, (char *)NULL); | |
1374 | xfree(cp); | |
1375 | public = key_load_public(filename, NULL); | |
1376 | debug("identity file %s type %d", filename, | |
1377 | public ? public->type : -1); | |
1378 | xfree(options.identity_files[i]); | |
1379 | options.identity_files[i] = filename; | |
1380 | options.identity_keys[i] = public; | |
1381 | } | |
1382 | bzero(pwname, strlen(pwname)); | |
1383 | xfree(pwname); | |
1384 | bzero(pwdir, strlen(pwdir)); | |
1385 | xfree(pwdir); | |
1386 | } |