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8efc0c15 | 1 | /* |
5260325f | 2 | * Author: Tatu Ylonen <ylo@cs.hut.fi> |
3 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland | |
4 | * All rights reserved | |
5260325f | 5 | * Ssh client program. This program can be used to log into a remote machine. |
6 | * The software supports strong authentication, encryption, and forwarding | |
7 | * of X11, TCP/IP, and authentication connections. | |
8 | * | |
bcbf86ec | 9 | * As far as I am concerned, the code I have written for this software |
10 | * can be used freely for any purpose. Any derived versions of this | |
11 | * software must be clearly marked as such, and if the derived work is | |
12 | * incompatible with the protocol description in the RFC file, it must be | |
13 | * called by a name other than "ssh" or "Secure Shell". | |
14 | * | |
15 | * Copyright (c) 1999 Niels Provos. All rights reserved. | |
d73a67d7 | 16 | * Copyright (c) 2000, 2001, 2002, 2003 Markus Friedl. All rights reserved. |
bcbf86ec | 17 | * |
18 | * Modified to work with SSL by Niels Provos <provos@citi.umich.edu> | |
19 | * in Canada (German citizen). | |
20 | * | |
21 | * Redistribution and use in source and binary forms, with or without | |
22 | * modification, are permitted provided that the following conditions | |
23 | * are met: | |
24 | * 1. Redistributions of source code must retain the above copyright | |
25 | * notice, this list of conditions and the following disclaimer. | |
26 | * 2. Redistributions in binary form must reproduce the above copyright | |
27 | * notice, this list of conditions and the following disclaimer in the | |
28 | * documentation and/or other materials provided with the distribution. | |
29 | * | |
30 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR | |
31 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES | |
32 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. | |
33 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, | |
34 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | |
35 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | |
36 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | |
37 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
38 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | |
39 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
5260325f | 40 | */ |
8efc0c15 | 41 | |
42 | #include "includes.h" | |
8cf98c65 | 43 | RCSID("$OpenBSD: ssh.c,v 1.233 2005/03/01 17:22:06 jmc Exp $"); |
8efc0c15 | 44 | |
a306f2dd | 45 | #include <openssl/evp.h> |
fa08c86b | 46 | #include <openssl/err.h> |
a306f2dd | 47 | |
8efc0c15 | 48 | #include "ssh.h" |
42f11eb2 | 49 | #include "ssh1.h" |
50 | #include "ssh2.h" | |
51 | #include "compat.h" | |
52 | #include "cipher.h" | |
53 | #include "xmalloc.h" | |
8efc0c15 | 54 | #include "packet.h" |
55 | #include "buffer.h" | |
5e96b616 | 56 | #include "bufaux.h" |
a5efa1bb | 57 | #include "channels.h" |
a306f2dd | 58 | #include "key.h" |
4c8722d9 | 59 | #include "authfd.h" |
a306f2dd | 60 | #include "authfile.h" |
42f11eb2 | 61 | #include "pathnames.h" |
5e96b616 | 62 | #include "dispatch.h" |
b5c334cc | 63 | #include "clientloop.h" |
42f11eb2 | 64 | #include "log.h" |
65 | #include "readconf.h" | |
66 | #include "sshconnect.h" | |
42f11eb2 | 67 | #include "misc.h" |
b2552997 | 68 | #include "kex.h" |
69 | #include "mac.h" | |
07d80252 | 70 | #include "sshpty.h" |
61a2c1da | 71 | #include "match.h" |
5e96b616 | 72 | #include "msg.h" |
73 | #include "monitor_fdpass.h" | |
6213295d | 74 | #include "uidswap.h" |
8efc0c15 | 75 | |
383546c4 | 76 | #ifdef SMARTCARD |
383546c4 | 77 | #include "scard.h" |
dd2495cb | 78 | #endif |
383546c4 | 79 | |
f601d847 | 80 | extern char *__progname; |
f601d847 | 81 | |
5260325f | 82 | /* Flag indicating whether debug mode is on. This can be set on the command line. */ |
8efc0c15 | 83 | int debug_flag = 0; |
84 | ||
a8be9f80 | 85 | /* Flag indicating whether a tty should be allocated */ |
8efc0c15 | 86 | int tty_flag = 0; |
8abcdba4 | 87 | int no_tty_flag = 0; |
88 | int force_tty_flag = 0; | |
8efc0c15 | 89 | |
8ce64345 | 90 | /* don't exec a shell */ |
91 | int no_shell_flag = 0; | |
8ce64345 | 92 | |
aa3378df | 93 | /* |
94 | * Flag indicating that nothing should be read from stdin. This can be set | |
95 | * on the command line. | |
96 | */ | |
8efc0c15 | 97 | int stdin_null_flag = 0; |
98 | ||
aa3378df | 99 | /* |
100 | * Flag indicating that ssh should fork after authentication. This is useful | |
c242fc96 | 101 | * so that the passphrase can be entered manually, and then ssh goes to the |
aa3378df | 102 | * background. |
103 | */ | |
8efc0c15 | 104 | int fork_after_authentication_flag = 0; |
105 | ||
aa3378df | 106 | /* |
107 | * General data structure for command line options and options configurable | |
108 | * in configuration files. See readconf.h. | |
109 | */ | |
8efc0c15 | 110 | Options options; |
111 | ||
e591b98a | 112 | /* optional user configfile */ |
113 | char *config = NULL; | |
114 | ||
aa3378df | 115 | /* |
116 | * Name of the host we are connecting to. This is the name given on the | |
117 | * command line, or the HostName specified for the user-supplied name in a | |
118 | * configuration file. | |
119 | */ | |
8efc0c15 | 120 | char *host; |
121 | ||
122 | /* socket address the host resolves to */ | |
48e671d5 | 123 | struct sockaddr_storage hostaddr; |
8efc0c15 | 124 | |
8002af61 | 125 | /* Private host keys. */ |
39c00dc2 | 126 | Sensitive sensitive_data; |
8efc0c15 | 127 | |
128 | /* Original real UID. */ | |
129 | uid_t original_real_uid; | |
3fb156df | 130 | uid_t original_effective_uid; |
8efc0c15 | 131 | |
8ce64345 | 132 | /* command to be executed */ |
133 | Buffer command; | |
134 | ||
ae810de7 | 135 | /* Should we execute a command or invoke a subsystem? */ |
136 | int subsystem_flag = 0; | |
137 | ||
e0ae8728 | 138 | /* # of replies received for global requests */ |
139 | static int client_global_request_id = 0; | |
140 | ||
6939bbd4 | 141 | /* pid of proxycommand child process */ |
142 | pid_t proxy_command_pid = 0; | |
143 | ||
5e96b616 | 144 | /* fd to control socket */ |
145 | int control_fd = -1; | |
146 | ||
f8c6db83 | 147 | /* Multiplexing control command */ |
148 | static u_int mux_command = SSHMUX_COMMAND_OPEN; | |
149 | ||
5e96b616 | 150 | /* Only used in control client mode */ |
151 | volatile sig_atomic_t control_client_terminate = 0; | |
152 | u_int control_server_pid = 0; | |
153 | ||
8efc0c15 | 154 | /* Prints a help message to the user. This function never returns. */ |
155 | ||
396c147e | 156 | static void |
5ca51e19 | 157 | usage(void) |
8efc0c15 | 158 | { |
182ccbba | 159 | fprintf(stderr, |
aeefce7a | 160 | "usage: ssh [-1246AaCfgkMNnqsTtVvXxY] [-b bind_address] [-c cipher_spec]\n" |
8cf98c65 | 161 | " [-D port] [-e escape_char] [-F configfile]\n" |
162 | " [-i identity_file] [-L [bind_address:]port:host:hostport]\n" | |
3867aa0a | 163 | " [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n" |
8cf98c65 | 164 | " [-R [bind_address:]port:host:hostport] [-S ctl_path]\n" |
aeefce7a | 165 | " [user@]hostname [command]\n" |
182ccbba | 166 | ); |
5260325f | 167 | exit(1); |
8efc0c15 | 168 | } |
169 | ||
396c147e | 170 | static int ssh_session(void); |
171 | static int ssh_session2(void); | |
172 | static void load_public_identity_files(void); | |
5e96b616 | 173 | static void control_client(const char *path); |
8ce64345 | 174 | |
5260325f | 175 | /* |
176 | * Main program for the ssh client. | |
177 | */ | |
8efc0c15 | 178 | int |
179 | main(int ac, char **av) | |
180 | { | |
b34bec32 | 181 | int i, opt, exit_status; |
1aafd17a | 182 | char *p, *cp, *line, buf[256]; |
5260325f | 183 | struct stat st; |
3b1a83df | 184 | struct passwd *pw; |
8ce64345 | 185 | int dummy; |
57dade33 | 186 | extern int optind, optreset; |
1812a662 | 187 | extern char *optarg; |
3867aa0a | 188 | Forward fwd; |
5260325f | 189 | |
fda04d7d | 190 | __progname = ssh_get_progname(av[0]); |
264dce47 | 191 | init_rng(); |
192 | ||
aa3378df | 193 | /* |
194 | * Save the original real uid. It will be needed later (uid-swapping | |
195 | * may clobber the real uid). | |
196 | */ | |
5260325f | 197 | original_real_uid = getuid(); |
198 | original_effective_uid = geteuid(); | |
aff51935 | 199 | |
9f324470 | 200 | /* |
201 | * Use uid-swapping to give up root privileges for the duration of | |
202 | * option processing. We will re-instantiate the rights when we are | |
203 | * ready to create the privileged port, and will permanently drop | |
204 | * them when the port has been created (actually, when the connection | |
205 | * has been made, as we may need to create the port several times). | |
206 | */ | |
207 | PRIV_END; | |
5260325f | 208 | |
7322ef0e | 209 | #ifdef HAVE_SETRLIMIT |
5260325f | 210 | /* If we are installed setuid root be careful to not drop core. */ |
211 | if (original_real_uid != original_effective_uid) { | |
212 | struct rlimit rlim; | |
213 | rlim.rlim_cur = rlim.rlim_max = 0; | |
214 | if (setrlimit(RLIMIT_CORE, &rlim) < 0) | |
215 | fatal("setrlimit failed: %.100s", strerror(errno)); | |
8efc0c15 | 216 | } |
3c62e7eb | 217 | #endif |
63bd8c36 | 218 | /* Get user data. */ |
219 | pw = getpwuid(original_real_uid); | |
220 | if (!pw) { | |
bbe88b6d | 221 | logit("You don't exist, go away!"); |
63bd8c36 | 222 | exit(1); |
223 | } | |
224 | /* Take a copy of the returned structure. */ | |
225 | pw = pwcopy(pw); | |
226 | ||
aa3378df | 227 | /* |
228 | * Set our umask to something reasonable, as some files are created | |
229 | * with the default umask. This will make them world-readable but | |
230 | * writable only by the owner, which is ok for all files for which we | |
231 | * don't set the modes explicitly. | |
232 | */ | |
5260325f | 233 | umask(022); |
234 | ||
5260325f | 235 | /* Initialize option structure to indicate that no values have been set. */ |
236 | initialize_options(&options); | |
237 | ||
238 | /* Parse command-line arguments. */ | |
239 | host = NULL; | |
240 | ||
f5a1a01a | 241 | again: |
242 | while ((opt = getopt(ac, av, | |
f8c6db83 | 243 | "1246ab:c:e:fgi:kl:m:no:p:qstvxACD:F:I:L:MNO:PR:S:TVXY")) != -1) { |
5260325f | 244 | switch (opt) { |
1f3bf5aa | 245 | case '1': |
246 | options.protocol = SSH_PROTO_1; | |
247 | break; | |
6ae2364d | 248 | case '2': |
249 | options.protocol = SSH_PROTO_2; | |
250 | break; | |
48e671d5 | 251 | case '4': |
1572b90f | 252 | options.address_family = AF_INET; |
48e671d5 | 253 | break; |
48e671d5 | 254 | case '6': |
1572b90f | 255 | options.address_family = AF_INET6; |
48e671d5 | 256 | break; |
5260325f | 257 | case 'n': |
258 | stdin_null_flag = 1; | |
259 | break; | |
5260325f | 260 | case 'f': |
261 | fork_after_authentication_flag = 1; | |
262 | stdin_null_flag = 1; | |
263 | break; | |
5260325f | 264 | case 'x': |
265 | options.forward_x11 = 0; | |
266 | break; | |
5260325f | 267 | case 'X': |
268 | options.forward_x11 = 1; | |
269 | break; | |
d73a67d7 | 270 | case 'Y': |
271 | options.forward_x11 = 1; | |
272 | options.forward_x11_trusted = 1; | |
273 | break; | |
5260325f | 274 | case 'g': |
275 | options.gateway_ports = 1; | |
276 | break; | |
f8c6db83 | 277 | case 'O': |
278 | if (strcmp(optarg, "check") == 0) | |
279 | mux_command = SSHMUX_COMMAND_ALIVE_CHECK; | |
280 | else if (strcmp(optarg, "exit") == 0) | |
281 | mux_command = SSHMUX_COMMAND_TERMINATE; | |
282 | else | |
283 | fatal("Invalid multiplex command."); | |
284 | break; | |
e59404d1 | 285 | case 'P': /* deprecated */ |
5260325f | 286 | options.use_privileged_port = 0; |
287 | break; | |
5260325f | 288 | case 'a': |
289 | options.forward_agent = 0; | |
290 | break; | |
71276795 | 291 | case 'A': |
292 | options.forward_agent = 1; | |
293 | break; | |
5260325f | 294 | case 'k': |
f7926e97 | 295 | options.gss_deleg_creds = 0; |
5260325f | 296 | break; |
5260325f | 297 | case 'i': |
298 | if (stat(optarg, &st) < 0) { | |
f5a1a01a | 299 | fprintf(stderr, "Warning: Identity file %s " |
ec304d66 | 300 | "not accessible: %s.\n", optarg, |
301 | strerror(errno)); | |
5260325f | 302 | break; |
303 | } | |
f5a1a01a | 304 | if (options.num_identity_files >= |
305 | SSH_MAX_IDENTITY_FILES) | |
306 | fatal("Too many identity files specified " | |
307 | "(max %d)", SSH_MAX_IDENTITY_FILES); | |
308 | options.identity_files[options.num_identity_files++] = | |
309 | xstrdup(optarg); | |
5260325f | 310 | break; |
383546c4 | 311 | case 'I': |
312 | #ifdef SMARTCARD | |
9ff6f66f | 313 | options.smartcard_device = xstrdup(optarg); |
dd2495cb | 314 | #else |
383546c4 | 315 | fprintf(stderr, "no support for smartcards.\n"); |
dd2495cb | 316 | #endif |
383546c4 | 317 | break; |
5260325f | 318 | case 't': |
8abcdba4 | 319 | if (tty_flag) |
320 | force_tty_flag = 1; | |
5260325f | 321 | tty_flag = 1; |
322 | break; | |
5260325f | 323 | case 'v': |
e053cd2c | 324 | if (debug_flag == 0) { |
bcbf86ec | 325 | debug_flag = 1; |
326 | options.log_level = SYSLOG_LEVEL_DEBUG1; | |
e053cd2c | 327 | } else { |
328 | if (options.log_level < SYSLOG_LEVEL_DEBUG3) | |
329 | options.log_level++; | |
bcbf86ec | 330 | break; |
e053cd2c | 331 | } |
59d4718a | 332 | /* FALLTHROUGH */ |
5260325f | 333 | case 'V': |
85ac7a84 | 334 | fprintf(stderr, "%s, %s\n", |
4526e8c2 | 335 | SSH_RELEASE, SSLeay_version(SSLEAY_VERSION)); |
5260325f | 336 | if (opt == 'V') |
337 | exit(0); | |
5260325f | 338 | break; |
5260325f | 339 | case 'q': |
340 | options.log_level = SYSLOG_LEVEL_QUIET; | |
341 | break; | |
5260325f | 342 | case 'e': |
343 | if (optarg[0] == '^' && optarg[2] == 0 && | |
f5a1a01a | 344 | (u_char) optarg[1] >= 64 && |
345 | (u_char) optarg[1] < 128) | |
1e3b8b07 | 346 | options.escape_char = (u_char) optarg[1] & 31; |
5260325f | 347 | else if (strlen(optarg) == 1) |
1e3b8b07 | 348 | options.escape_char = (u_char) optarg[0]; |
5260325f | 349 | else if (strcmp(optarg, "none") == 0) |
4bf9c10e | 350 | options.escape_char = SSH_ESCAPECHAR_NONE; |
5260325f | 351 | else { |
f5a1a01a | 352 | fprintf(stderr, "Bad escape character '%s'.\n", |
353 | optarg); | |
5260325f | 354 | exit(1); |
355 | } | |
356 | break; | |
5260325f | 357 | case 'c': |
a306f2dd | 358 | if (ciphers_valid(optarg)) { |
359 | /* SSH2 only */ | |
360 | options.ciphers = xstrdup(optarg); | |
d77347cc | 361 | options.cipher = SSH_CIPHER_INVALID; |
a306f2dd | 362 | } else { |
363 | /* SSH1 only */ | |
c523303b | 364 | options.cipher = cipher_number(optarg); |
365 | if (options.cipher == -1) { | |
f5a1a01a | 366 | fprintf(stderr, |
367 | "Unknown cipher type '%s'\n", | |
368 | optarg); | |
a306f2dd | 369 | exit(1); |
370 | } | |
f5a1a01a | 371 | if (options.cipher == SSH_CIPHER_3DES) |
c523303b | 372 | options.ciphers = "3des-cbc"; |
f5a1a01a | 373 | else if (options.cipher == SSH_CIPHER_BLOWFISH) |
c523303b | 374 | options.ciphers = "blowfish-cbc"; |
f5a1a01a | 375 | else |
c523303b | 376 | options.ciphers = (char *)-1; |
5260325f | 377 | } |
378 | break; | |
b2552997 | 379 | case 'm': |
380 | if (mac_valid(optarg)) | |
381 | options.macs = xstrdup(optarg); | |
382 | else { | |
f5a1a01a | 383 | fprintf(stderr, "Unknown mac type '%s'\n", |
384 | optarg); | |
b2552997 | 385 | exit(1); |
386 | } | |
387 | break; | |
5e96b616 | 388 | case 'M': |
4598add7 | 389 | options.control_master = |
390 | (options.control_master >= 1) ? 2 : 1; | |
5e96b616 | 391 | break; |
5260325f | 392 | case 'p': |
2d2a2c65 | 393 | options.port = a2port(optarg); |
394 | if (options.port == 0) { | |
6031af8d | 395 | fprintf(stderr, "Bad port '%s'\n", optarg); |
396 | exit(1); | |
397 | } | |
5260325f | 398 | break; |
5260325f | 399 | case 'l': |
400 | options.user = optarg; | |
401 | break; | |
d2e3df16 | 402 | |
403 | case 'L': | |
3867aa0a | 404 | if (parse_forward(&fwd, optarg)) |
405 | add_local_forward(&options, &fwd); | |
406 | else { | |
f5a1a01a | 407 | fprintf(stderr, |
3867aa0a | 408 | "Bad local forwarding specification '%s'\n", |
f5a1a01a | 409 | optarg); |
3867aa0a | 410 | exit(1); |
5260325f | 411 | } |
3867aa0a | 412 | break; |
413 | ||
414 | case 'R': | |
415 | if (parse_forward(&fwd, optarg)) { | |
416 | add_remote_forward(&options, &fwd); | |
417 | } else { | |
f5a1a01a | 418 | fprintf(stderr, |
3867aa0a | 419 | "Bad remote forwarding specification " |
420 | "'%s'\n", optarg); | |
d2e3df16 | 421 | exit(1); |
5260325f | 422 | } |
5260325f | 423 | break; |
0490e609 | 424 | |
425 | case 'D': | |
3867aa0a | 426 | cp = p = xstrdup(optarg); |
427 | memset(&fwd, '\0', sizeof(fwd)); | |
428 | fwd.connect_host = "socks"; | |
429 | if ((fwd.listen_host = hpdelim(&cp)) == NULL) { | |
430 | fprintf(stderr, "Bad dynamic forwarding " | |
431 | "specification '%.100s'\n", optarg); | |
432 | exit(1); | |
433 | } | |
434 | if (cp != NULL) { | |
435 | fwd.listen_port = a2port(cp); | |
436 | fwd.listen_host = cleanhostname(fwd.listen_host); | |
437 | } else { | |
438 | fwd.listen_port = a2port(fwd.listen_host); | |
439 | fwd.listen_host = ""; | |
440 | } | |
441 | ||
442 | if (fwd.listen_port == 0) { | |
f5a1a01a | 443 | fprintf(stderr, "Bad dynamic port '%s'\n", |
444 | optarg); | |
6031af8d | 445 | exit(1); |
446 | } | |
3867aa0a | 447 | add_local_forward(&options, &fwd); |
448 | xfree(p); | |
0490e609 | 449 | break; |
450 | ||
5260325f | 451 | case 'C': |
452 | options.compression = 1; | |
453 | break; | |
8ce64345 | 454 | case 'N': |
455 | no_shell_flag = 1; | |
456 | no_tty_flag = 1; | |
457 | break; | |
8ce64345 | 458 | case 'T': |
459 | no_tty_flag = 1; | |
460 | break; | |
5260325f | 461 | case 'o': |
462 | dummy = 1; | |
1aafd17a | 463 | line = xstrdup(optarg); |
f5a1a01a | 464 | if (process_config_line(&options, host ? host : "", |
1aafd17a | 465 | line, "command-line", 0, &dummy) != 0) |
5260325f | 466 | exit(1); |
1aafd17a | 467 | xfree(line); |
5260325f | 468 | break; |
ae810de7 | 469 | case 's': |
470 | subsystem_flag = 1; | |
471 | break; | |
5e96b616 | 472 | case 'S': |
473 | if (options.control_path != NULL) | |
474 | free(options.control_path); | |
475 | options.control_path = xstrdup(optarg); | |
5e96b616 | 476 | break; |
3435f5a6 | 477 | case 'b': |
478 | options.bind_address = optarg; | |
479 | break; | |
e591b98a | 480 | case 'F': |
481 | config = optarg; | |
482 | break; | |
5260325f | 483 | default: |
484 | usage(); | |
485 | } | |
486 | } | |
487 | ||
f5a1a01a | 488 | ac -= optind; |
489 | av += optind; | |
490 | ||
491 | if (ac > 0 && !host && **av != '-') { | |
15748b4d | 492 | if (strrchr(*av, '@')) { |
f5a1a01a | 493 | p = xstrdup(*av); |
15748b4d | 494 | cp = strrchr(p, '@'); |
f5a1a01a | 495 | if (cp == NULL || cp == p) |
496 | usage(); | |
497 | options.user = p; | |
498 | *cp = '\0'; | |
499 | host = ++cp; | |
500 | } else | |
501 | host = *av; | |
978ebf99 | 502 | if (ac > 1) { |
503 | optind = optreset = 1; | |
f5a1a01a | 504 | goto again; |
505 | } | |
978ebf99 | 506 | ac--, av++; |
f5a1a01a | 507 | } |
508 | ||
5260325f | 509 | /* Check that we got a host name. */ |
510 | if (!host) | |
8efc0c15 | 511 | usage(); |
5260325f | 512 | |
22d89d24 | 513 | SSLeay_add_all_algorithms(); |
fa08c86b | 514 | ERR_load_crypto_strings(); |
22d89d24 | 515 | |
5260325f | 516 | /* Initialize the command to execute on remote host. */ |
517 | buffer_init(&command); | |
518 | ||
aa3378df | 519 | /* |
520 | * Save the command to execute on the remote host in a buffer. There | |
521 | * is no limit on the length of the command, except by the maximum | |
522 | * packet size. Also sets the tty flag if there is no command. | |
523 | */ | |
f5a1a01a | 524 | if (!ac) { |
5260325f | 525 | /* No command specified - execute shell on a tty. */ |
526 | tty_flag = 1; | |
ae810de7 | 527 | if (subsystem_flag) { |
f5a1a01a | 528 | fprintf(stderr, |
529 | "You must specify a subsystem to invoke.\n"); | |
ae810de7 | 530 | usage(); |
531 | } | |
5260325f | 532 | } else { |
f5a1a01a | 533 | /* A command has been specified. Store it into the buffer. */ |
534 | for (i = 0; i < ac; i++) { | |
535 | if (i) | |
5260325f | 536 | buffer_append(&command, " ", 1); |
537 | buffer_append(&command, av[i], strlen(av[i])); | |
538 | } | |
8efc0c15 | 539 | } |
5260325f | 540 | |
541 | /* Cannot fork to background if no command. */ | |
14a9a859 | 542 | if (fork_after_authentication_flag && buffer_len(&command) == 0 && !no_shell_flag) |
5260325f | 543 | fatal("Cannot fork into background without a command to execute."); |
544 | ||
545 | /* Allocate a tty by default if no command specified. */ | |
546 | if (buffer_len(&command) == 0) | |
547 | tty_flag = 1; | |
548 | ||
343288b8 | 549 | /* Force no tty */ |
0b6fbf03 | 550 | if (no_tty_flag) |
551 | tty_flag = 0; | |
5260325f | 552 | /* Do not allocate a tty if stdin is not a tty. */ |
8abcdba4 | 553 | if (!isatty(fileno(stdin)) && !force_tty_flag) { |
5260325f | 554 | if (tty_flag) |
bbe88b6d | 555 | logit("Pseudo-terminal will not be allocated because stdin is not a terminal."); |
5260325f | 556 | tty_flag = 0; |
557 | } | |
8ce64345 | 558 | |
20244695 | 559 | /* |
560 | * Initialize "log" output. Since we are the client all output | |
561 | * actually goes to stderr. | |
562 | */ | |
cc44f691 | 563 | log_init(av[0], options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level, |
564 | SYSLOG_FACILITY_USER, 1); | |
5260325f | 565 | |
e591b98a | 566 | /* |
567 | * Read per-user configuration file. Ignore the system wide config | |
568 | * file if the user specifies a config file on the command line. | |
569 | */ | |
570 | if (config != NULL) { | |
f7f14143 | 571 | if (!read_config_file(config, host, &options, 0)) |
93111dfa | 572 | fatal("Can't open user config file %.100s: " |
573 | "%.100s", config, strerror(errno)); | |
e591b98a | 574 | } else { |
575 | snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, | |
576 | _PATH_SSH_USER_CONFFILE); | |
9f6cab4b | 577 | (void)read_config_file(buf, host, &options, 1); |
e591b98a | 578 | |
f67792f2 | 579 | /* Read systemwide configuration file after use config. */ |
f2107e97 | 580 | (void)read_config_file(_PATH_HOST_CONFIG_FILE, host, |
9f6cab4b | 581 | &options, 0); |
e591b98a | 582 | } |
5260325f | 583 | |
584 | /* Fill configuration defaults. */ | |
585 | fill_default_options(&options); | |
586 | ||
1572b90f | 587 | channel_set_af(options.address_family); |
588 | ||
5260325f | 589 | /* reinit */ |
20244695 | 590 | log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, 1); |
5260325f | 591 | |
e339aa53 | 592 | seed_rng(); |
593 | ||
5260325f | 594 | if (options.user == NULL) |
595 | options.user = xstrdup(pw->pw_name); | |
596 | ||
597 | if (options.hostname != NULL) | |
598 | host = options.hostname; | |
599 | ||
03c82656 | 600 | /* force lowercase for hostkey matching */ |
601 | if (options.host_key_alias != NULL) { | |
602 | for (p = options.host_key_alias; *p; p++) | |
603 | if (isupper(*p)) | |
604 | *p = tolower(*p); | |
605 | } | |
606 | ||
f78bde70 | 607 | if (options.proxy_command != NULL && |
608 | strcmp(options.proxy_command, "none") == 0) | |
609 | options.proxy_command = NULL; | |
610 | ||
5e96b616 | 611 | if (options.control_path != NULL) { |
612 | options.control_path = tilde_expand_filename( | |
613 | options.control_path, original_real_uid); | |
614 | } | |
615 | if (options.control_path != NULL && options.control_master == 0) | |
616 | control_client(options.control_path); /* This doesn't return */ | |
617 | ||
6ffc9c88 | 618 | /* Open a connection to the remote host. */ |
1572b90f | 619 | if (ssh_connect(host, &hostaddr, options.port, |
620 | options.address_family, options.connection_attempts, | |
d514c907 | 621 | #ifdef HAVE_CYGWIN |
622 | options.use_privileged_port, | |
623 | #else | |
3fb156df | 624 | original_effective_uid == 0 && options.use_privileged_port, |
d514c907 | 625 | #endif |
de60473e | 626 | options.proxy_command) != 0) |
b34bec32 | 627 | exit(1); |
5260325f | 628 | |
aa3378df | 629 | /* |
630 | * If we successfully made the connection, load the host private key | |
631 | * in case we will need it later for combined rsa-rhosts | |
632 | * authentication. This must be done before releasing extra | |
633 | * privileges, because the file is only readable by root. | |
78660ed4 | 634 | * If we cannot access the private keys, load the public keys |
635 | * instead and try to execute the ssh-keysign helper instead. | |
aa3378df | 636 | */ |
8002af61 | 637 | sensitive_data.nkeys = 0; |
638 | sensitive_data.keys = NULL; | |
39c00dc2 | 639 | sensitive_data.external_keysign = 0; |
b34bec32 | 640 | if (options.rhosts_rsa_authentication || |
641 | options.hostbased_authentication) { | |
8002af61 | 642 | sensitive_data.nkeys = 3; |
343288b8 | 643 | sensitive_data.keys = xmalloc(sensitive_data.nkeys * |
644 | sizeof(Key)); | |
3fb156df | 645 | |
646 | PRIV_START; | |
8002af61 | 647 | sensitive_data.keys[0] = key_load_private_type(KEY_RSA1, |
aeaa3d9e | 648 | _PATH_HOST_KEY_FILE, "", NULL); |
8002af61 | 649 | sensitive_data.keys[1] = key_load_private_type(KEY_DSA, |
650 | _PATH_HOST_DSA_KEY_FILE, "", NULL); | |
651 | sensitive_data.keys[2] = key_load_private_type(KEY_RSA, | |
652 | _PATH_HOST_RSA_KEY_FILE, "", NULL); | |
3fb156df | 653 | PRIV_END; |
39c00dc2 | 654 | |
60cd0a97 | 655 | if (options.hostbased_authentication == 1 && |
656 | sensitive_data.keys[0] == NULL && | |
39c00dc2 | 657 | sensitive_data.keys[1] == NULL && |
658 | sensitive_data.keys[2] == NULL) { | |
659 | sensitive_data.keys[1] = key_load_public( | |
660 | _PATH_HOST_DSA_KEY_FILE, NULL); | |
661 | sensitive_data.keys[2] = key_load_public( | |
662 | _PATH_HOST_RSA_KEY_FILE, NULL); | |
663 | sensitive_data.external_keysign = 1; | |
664 | } | |
5260325f | 665 | } |
aa3378df | 666 | /* |
667 | * Get rid of any extra privileges that we may have. We will no | |
668 | * longer need them. Also, extra privileges could make it very hard | |
669 | * to read identity files and other non-world-readable files from the | |
670 | * user's home directory if it happens to be on a NFS volume where | |
671 | * root is mapped to nobody. | |
672 | */ | |
6213295d | 673 | if (original_effective_uid == 0) { |
674 | PRIV_START; | |
675 | permanently_set_uid(pw); | |
676 | } | |
5260325f | 677 | |
aa3378df | 678 | /* |
679 | * Now that we are back to our own permissions, create ~/.ssh | |
680 | * directory if it doesn\'t already exist. | |
681 | */ | |
c3abff07 | 682 | snprintf(buf, sizeof buf, "%.100s%s%.100s", pw->pw_dir, strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR); |
5260325f | 683 | if (stat(buf, &st) < 0) |
704b1659 | 684 | if (mkdir(buf, 0700) < 0) |
5260325f | 685 | error("Could not create directory '%.200s'.", buf); |
686 | ||
fee56204 | 687 | /* load options.identity_files */ |
688 | load_public_identity_files(); | |
689 | ||
690 | /* Expand ~ in known host file names. */ | |
691 | /* XXX mem-leaks: */ | |
fa08c86b | 692 | options.system_hostfile = |
693 | tilde_expand_filename(options.system_hostfile, original_real_uid); | |
694 | options.user_hostfile = | |
695 | tilde_expand_filename(options.user_hostfile, original_real_uid); | |
696 | options.system_hostfile2 = | |
697 | tilde_expand_filename(options.system_hostfile2, original_real_uid); | |
698 | options.user_hostfile2 = | |
699 | tilde_expand_filename(options.user_hostfile2, original_real_uid); | |
5260325f | 700 | |
67b75437 | 701 | signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */ |
702 | ||
5260325f | 703 | /* Log into the remote system. This never returns if the login fails. */ |
39c00dc2 | 704 | ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr, pw); |
8002af61 | 705 | |
706 | /* We no longer need the private host keys. Clear them now. */ | |
707 | if (sensitive_data.nkeys != 0) { | |
708 | for (i = 0; i < sensitive_data.nkeys; i++) { | |
709 | if (sensitive_data.keys[i] != NULL) { | |
710 | /* Destroys contents safely */ | |
711 | debug3("clear hostkey %d", i); | |
712 | key_free(sensitive_data.keys[i]); | |
713 | sensitive_data.keys[i] = NULL; | |
714 | } | |
715 | } | |
716 | xfree(sensitive_data.keys); | |
717 | } | |
05b7537a | 718 | for (i = 0; i < options.num_identity_files; i++) { |
719 | if (options.identity_files[i]) { | |
720 | xfree(options.identity_files[i]); | |
721 | options.identity_files[i] = NULL; | |
722 | } | |
723 | if (options.identity_keys[i]) { | |
724 | key_free(options.identity_keys[i]); | |
725 | options.identity_keys[i] = NULL; | |
726 | } | |
727 | } | |
5260325f | 728 | |
8ce64345 | 729 | exit_status = compat20 ? ssh_session2() : ssh_session(); |
730 | packet_close(); | |
6939bbd4 | 731 | |
5e96b616 | 732 | if (options.control_path != NULL && control_fd != -1) |
733 | unlink(options.control_path); | |
734 | ||
6939bbd4 | 735 | /* |
aff51935 | 736 | * Send SIGHUP to proxy command if used. We don't wait() in |
6939bbd4 | 737 | * case it hangs and instead rely on init to reap the child |
738 | */ | |
739 | if (proxy_command_pid > 1) | |
740 | kill(proxy_command_pid, SIGHUP); | |
741 | ||
8ce64345 | 742 | return exit_status; |
743 | } | |
744 | ||
d73a67d7 | 745 | #define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1" |
746 | ||
396c147e | 747 | static void |
b48eeb07 | 748 | x11_get_proto(char **_proto, char **_data) |
0b242b12 | 749 | { |
d73a67d7 | 750 | char cmd[1024]; |
0b242b12 | 751 | char line[512]; |
d73a67d7 | 752 | char xdisplay[512]; |
b48eeb07 | 753 | static char proto[512], data[512]; |
0b242b12 | 754 | FILE *f; |
d73a67d7 | 755 | int got_data = 0, generated = 0, do_unlink = 0, i; |
756 | char *display, *xauthdir, *xauthfile; | |
5d185586 | 757 | struct stat st; |
0b242b12 | 758 | |
d73a67d7 | 759 | xauthdir = xauthfile = NULL; |
b48eeb07 | 760 | *_proto = proto; |
761 | *_data = data; | |
762 | proto[0] = data[0] = '\0'; | |
d73a67d7 | 763 | |
5d185586 | 764 | if (!options.xauth_location || |
765 | (stat(options.xauth_location, &st) == -1)) { | |
766 | debug("No xauth program."); | |
767 | } else { | |
768 | if ((display = getenv("DISPLAY")) == NULL) { | |
769 | debug("x11_get_proto: DISPLAY not set"); | |
770 | return; | |
771 | } | |
d73a67d7 | 772 | /* |
773 | * Handle FamilyLocal case where $DISPLAY does | |
774 | * not match an authorization entry. For this we | |
775 | * just try "xauth list unix:displaynum.screennum". | |
776 | * XXX: "localhost" match to determine FamilyLocal | |
777 | * is not perfect. | |
778 | */ | |
779 | if (strncmp(display, "localhost:", 10) == 0) { | |
780 | snprintf(xdisplay, sizeof(xdisplay), "unix:%s", | |
781 | display + 10); | |
782 | display = xdisplay; | |
783 | } | |
784 | if (options.forward_x11_trusted == 0) { | |
785 | xauthdir = xmalloc(MAXPATHLEN); | |
786 | xauthfile = xmalloc(MAXPATHLEN); | |
787 | strlcpy(xauthdir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN); | |
788 | if (mkdtemp(xauthdir) != NULL) { | |
789 | do_unlink = 1; | |
790 | snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile", | |
791 | xauthdir); | |
792 | snprintf(cmd, sizeof(cmd), | |
793 | "%s -f %s generate %s " SSH_X11_PROTO | |
c876ee7e | 794 | " untrusted timeout 1200 2>" _PATH_DEVNULL, |
d73a67d7 | 795 | options.xauth_location, xauthfile, display); |
796 | debug2("x11_get_proto: %s", cmd); | |
797 | if (system(cmd) == 0) | |
798 | generated = 1; | |
799 | } | |
800 | } | |
801 | snprintf(cmd, sizeof(cmd), | |
802 | "%s %s%s list %s . 2>" _PATH_DEVNULL, | |
803 | options.xauth_location, | |
804 | generated ? "-f " : "" , | |
805 | generated ? xauthfile : "", | |
806 | display); | |
807 | debug2("x11_get_proto: %s", cmd); | |
808 | f = popen(cmd, "r"); | |
fa649821 | 809 | if (f && fgets(line, sizeof(line), f) && |
b48eeb07 | 810 | sscanf(line, "%*s %511s %511s", proto, data) == 2) |
fa649821 | 811 | got_data = 1; |
812 | if (f) | |
813 | pclose(f); | |
814 | } | |
d73a67d7 | 815 | |
816 | if (do_unlink) { | |
817 | unlink(xauthfile); | |
818 | rmdir(xauthdir); | |
819 | } | |
820 | if (xauthdir) | |
821 | xfree(xauthdir); | |
822 | if (xauthfile) | |
823 | xfree(xauthfile); | |
824 | ||
0b242b12 | 825 | /* |
826 | * If we didn't get authentication data, just make up some | |
827 | * data. The forwarding code will check the validity of the | |
828 | * response anyway, and substitute this data. The X11 | |
829 | * server, however, will ignore this fake data and use | |
830 | * whatever authentication mechanisms it was using otherwise | |
831 | * for the local connection. | |
832 | */ | |
833 | if (!got_data) { | |
ca75d7de | 834 | u_int32_t rnd = 0; |
0b242b12 | 835 | |
d73a67d7 | 836 | logit("Warning: No xauth data; " |
837 | "using fake authentication data for X11 forwarding."); | |
838 | strlcpy(proto, SSH_X11_PROTO, sizeof proto); | |
0b242b12 | 839 | for (i = 0; i < 16; i++) { |
840 | if (i % 4 == 0) | |
ca75d7de | 841 | rnd = arc4random(); |
d73a67d7 | 842 | snprintf(data + 2 * i, sizeof data - 2 * i, "%02x", |
ca75d7de | 843 | rnd & 0xff); |
844 | rnd >>= 8; | |
0b242b12 | 845 | } |
846 | } | |
847 | } | |
848 | ||
396c147e | 849 | static void |
fa08c86b | 850 | ssh_init_forwarding(void) |
851 | { | |
02a024dd | 852 | int success = 0; |
fa08c86b | 853 | int i; |
02a024dd | 854 | |
fa08c86b | 855 | /* Initiate local TCP/IP port forwardings. */ |
856 | for (i = 0; i < options.num_local_forwards; i++) { | |
3867aa0a | 857 | debug("Local connections to %.200s:%d forwarded to remote " |
858 | "address %.200s:%d", | |
859 | (options.local_forwards[i].listen_host == NULL) ? | |
860 | (options.gateway_ports ? "*" : "LOCALHOST") : | |
861 | options.local_forwards[i].listen_host, | |
862 | options.local_forwards[i].listen_port, | |
863 | options.local_forwards[i].connect_host, | |
864 | options.local_forwards[i].connect_port); | |
5641aefa | 865 | success += channel_setup_local_fwd_listener( |
3867aa0a | 866 | options.local_forwards[i].listen_host, |
867 | options.local_forwards[i].listen_port, | |
868 | options.local_forwards[i].connect_host, | |
869 | options.local_forwards[i].connect_port, | |
fa08c86b | 870 | options.gateway_ports); |
871 | } | |
02a024dd | 872 | if (i > 0 && success == 0) |
873 | error("Could not request local forwarding."); | |
fa08c86b | 874 | |
875 | /* Initiate remote TCP/IP port forwardings. */ | |
876 | for (i = 0; i < options.num_remote_forwards; i++) { | |
3867aa0a | 877 | debug("Remote connections from %.200s:%d forwarded to " |
878 | "local address %.200s:%d", | |
879 | options.remote_forwards[i].listen_host, | |
880 | options.remote_forwards[i].listen_port, | |
881 | options.remote_forwards[i].connect_host, | |
882 | options.remote_forwards[i].connect_port); | |
fa08c86b | 883 | channel_request_remote_forwarding( |
3867aa0a | 884 | options.remote_forwards[i].listen_host, |
885 | options.remote_forwards[i].listen_port, | |
886 | options.remote_forwards[i].connect_host, | |
887 | options.remote_forwards[i].connect_port); | |
fa08c86b | 888 | } |
889 | } | |
890 | ||
396c147e | 891 | static void |
fa08c86b | 892 | check_agent_present(void) |
893 | { | |
894 | if (options.forward_agent) { | |
895 | /* Clear agent forwarding if we don\'t have an agent. */ | |
8b10e20e | 896 | if (!ssh_agent_present()) |
fa08c86b | 897 | options.forward_agent = 0; |
fa08c86b | 898 | } |
899 | } | |
900 | ||
396c147e | 901 | static int |
8ce64345 | 902 | ssh_session(void) |
903 | { | |
904 | int type; | |
8ce64345 | 905 | int interactive = 0; |
906 | int have_tty = 0; | |
907 | struct winsize ws; | |
8ce64345 | 908 | char *cp; |
909 | ||
5260325f | 910 | /* Enable compression if requested. */ |
911 | if (options.compression) { | |
912 | debug("Requesting compression at level %d.", options.compression_level); | |
913 | ||
914 | if (options.compression_level < 1 || options.compression_level > 9) | |
915 | fatal("Compression level must be from 1 (fast) to 9 (slow, best)."); | |
916 | ||
917 | /* Send the request. */ | |
918 | packet_start(SSH_CMSG_REQUEST_COMPRESSION); | |
919 | packet_put_int(options.compression_level); | |
920 | packet_send(); | |
921 | packet_write_wait(); | |
54a5250f | 922 | type = packet_read(); |
5260325f | 923 | if (type == SSH_SMSG_SUCCESS) |
924 | packet_start_compression(options.compression_level); | |
925 | else if (type == SSH_SMSG_FAILURE) | |
bbe88b6d | 926 | logit("Warning: Remote host refused compression."); |
5260325f | 927 | else |
928 | packet_disconnect("Protocol error waiting for compression response."); | |
929 | } | |
930 | /* Allocate a pseudo tty if appropriate. */ | |
931 | if (tty_flag) { | |
932 | debug("Requesting pty."); | |
933 | ||
934 | /* Start the packet. */ | |
935 | packet_start(SSH_CMSG_REQUEST_PTY); | |
936 | ||
937 | /* Store TERM in the packet. There is no limit on the | |
938 | length of the string. */ | |
939 | cp = getenv("TERM"); | |
940 | if (!cp) | |
941 | cp = ""; | |
449c5ba5 | 942 | packet_put_cstring(cp); |
5260325f | 943 | |
944 | /* Store window size in the packet. */ | |
945 | if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0) | |
946 | memset(&ws, 0, sizeof(ws)); | |
947 | packet_put_int(ws.ws_row); | |
948 | packet_put_int(ws.ws_col); | |
949 | packet_put_int(ws.ws_xpixel); | |
950 | packet_put_int(ws.ws_ypixel); | |
951 | ||
952 | /* Store tty modes in the packet. */ | |
30dcc918 | 953 | tty_make_modes(fileno(stdin), NULL); |
5260325f | 954 | |
955 | /* Send the packet, and wait for it to leave. */ | |
956 | packet_send(); | |
957 | packet_write_wait(); | |
958 | ||
959 | /* Read response from the server. */ | |
54a5250f | 960 | type = packet_read(); |
4fe2af09 | 961 | if (type == SSH_SMSG_SUCCESS) { |
5260325f | 962 | interactive = 1; |
8ce64345 | 963 | have_tty = 1; |
4fe2af09 | 964 | } else if (type == SSH_SMSG_FAILURE) |
bbe88b6d | 965 | logit("Warning: Remote host failed or refused to allocate a pseudo tty."); |
5260325f | 966 | else |
967 | packet_disconnect("Protocol error waiting for pty request response."); | |
968 | } | |
969 | /* Request X11 forwarding if enabled and DISPLAY is set. */ | |
970 | if (options.forward_x11 && getenv("DISPLAY") != NULL) { | |
b48eeb07 | 971 | char *proto, *data; |
0b242b12 | 972 | /* Get reasonable local authentication information. */ |
b48eeb07 | 973 | x11_get_proto(&proto, &data); |
0b242b12 | 974 | /* Request forwarding with authentication spoofing. */ |
5260325f | 975 | debug("Requesting X11 forwarding with authentication spoofing."); |
0b242b12 | 976 | x11_request_forwarding_with_spoofing(0, proto, data); |
5260325f | 977 | |
978 | /* Read response from the server. */ | |
54a5250f | 979 | type = packet_read(); |
5260325f | 980 | if (type == SSH_SMSG_SUCCESS) { |
5260325f | 981 | interactive = 1; |
0b242b12 | 982 | } else if (type == SSH_SMSG_FAILURE) { |
bbe88b6d | 983 | logit("Warning: Remote host denied X11 forwarding."); |
0b242b12 | 984 | } else { |
5260325f | 985 | packet_disconnect("Protocol error waiting for X11 forwarding"); |
0b242b12 | 986 | } |
5260325f | 987 | } |
988 | /* Tell the packet module whether this is an interactive session. */ | |
b5c334cc | 989 | packet_set_interactive(interactive); |
5260325f | 990 | |
991 | /* Request authentication agent forwarding if appropriate. */ | |
fa08c86b | 992 | check_agent_present(); |
993 | ||
5260325f | 994 | if (options.forward_agent) { |
995 | debug("Requesting authentication agent forwarding."); | |
996 | auth_request_forwarding(); | |
997 | ||
998 | /* Read response from the server. */ | |
54a5250f | 999 | type = packet_read(); |
95500969 | 1000 | packet_check_eom(); |
5260325f | 1001 | if (type != SSH_SMSG_SUCCESS) |
bbe88b6d | 1002 | logit("Warning: Remote host denied authentication agent forwarding."); |
5260325f | 1003 | } |
8efc0c15 | 1004 | |
fa08c86b | 1005 | /* Initiate port forwardings. */ |
1006 | ssh_init_forwarding(); | |
5260325f | 1007 | |
aa3378df | 1008 | /* If requested, let ssh continue in the background. */ |
6ae2364d | 1009 | if (fork_after_authentication_flag) |
aa3378df | 1010 | if (daemon(1, 1) < 0) |
1011 | fatal("daemon() failed: %.200s", strerror(errno)); | |
1012 | ||
1013 | /* | |
1014 | * If a command was specified on the command line, execute the | |
1015 | * command now. Otherwise request the server to start a shell. | |
1016 | */ | |
5260325f | 1017 | if (buffer_len(&command) > 0) { |
1018 | int len = buffer_len(&command); | |
1019 | if (len > 900) | |
1020 | len = 900; | |
6c0fa2b1 | 1021 | debug("Sending command: %.*s", len, (u_char *)buffer_ptr(&command)); |
5260325f | 1022 | packet_start(SSH_CMSG_EXEC_CMD); |
1023 | packet_put_string(buffer_ptr(&command), buffer_len(&command)); | |
1024 | packet_send(); | |
1025 | packet_write_wait(); | |
1026 | } else { | |
1027 | debug("Requesting shell."); | |
1028 | packet_start(SSH_CMSG_EXEC_SHELL); | |
1029 | packet_send(); | |
1030 | packet_write_wait(); | |
1031 | } | |
1032 | ||
1033 | /* Enter the interactive session. */ | |
4bf9c10e | 1034 | return client_loop(have_tty, tty_flag ? |
1035 | options.escape_char : SSH_ESCAPECHAR_NONE, 0); | |
8ce64345 | 1036 | } |
5260325f | 1037 | |
396c147e | 1038 | static void |
5e96b616 | 1039 | ssh_subsystem_reply(int type, u_int32_t seq, void *ctxt) |
1f3bf5aa | 1040 | { |
1041 | int id, len; | |
1042 | ||
1043 | id = packet_get_int(); | |
1044 | len = buffer_len(&command); | |
ce91d6f8 | 1045 | if (len > 900) |
1046 | len = 900; | |
95500969 | 1047 | packet_check_eom(); |
1f3bf5aa | 1048 | if (type == SSH2_MSG_CHANNEL_FAILURE) |
1049 | fatal("Request for subsystem '%.*s' failed on channel %d", | |
6c0fa2b1 | 1050 | len, (u_char *)buffer_ptr(&command), id); |
1f3bf5aa | 1051 | } |
1052 | ||
e0ae8728 | 1053 | void |
5d8d32a3 | 1054 | client_global_request_reply_fwd(int type, u_int32_t seq, void *ctxt) |
e0ae8728 | 1055 | { |
1056 | int i; | |
1057 | ||
1058 | i = client_global_request_id++; | |
5d8d32a3 | 1059 | if (i >= options.num_remote_forwards) |
e0ae8728 | 1060 | return; |
e0ae8728 | 1061 | debug("remote forward %s for: listen %d, connect %s:%d", |
1062 | type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure", | |
3867aa0a | 1063 | options.remote_forwards[i].listen_port, |
1064 | options.remote_forwards[i].connect_host, | |
1065 | options.remote_forwards[i].connect_port); | |
e0ae8728 | 1066 | if (type == SSH2_MSG_REQUEST_FAILURE) |
3867aa0a | 1067 | logit("Warning: remote port forwarding failed for listen " |
1068 | "port %d", options.remote_forwards[i].listen_port); | |
e0ae8728 | 1069 | } |
1070 | ||
396c147e | 1071 | static void |
5e96b616 | 1072 | ssh_control_listener(void) |
8ce64345 | 1073 | { |
5e96b616 | 1074 | struct sockaddr_un addr; |
1075 | mode_t old_umask; | |
4b5df124 | 1076 | int addr_len; |
1077 | ||
0d34d6ce | 1078 | if (options.control_path == NULL || options.control_master <= 0) |
5e96b616 | 1079 | return; |
b5c334cc | 1080 | |
5e96b616 | 1081 | memset(&addr, '\0', sizeof(addr)); |
1082 | addr.sun_family = AF_UNIX; | |
4b5df124 | 1083 | addr_len = offsetof(struct sockaddr_un, sun_path) + |
5e96b616 | 1084 | strlen(options.control_path) + 1; |
8ce64345 | 1085 | |
5e96b616 | 1086 | if (strlcpy(addr.sun_path, options.control_path, |
1087 | sizeof(addr.sun_path)) >= sizeof(addr.sun_path)) | |
1088 | fatal("ControlPath too long"); | |
8ce64345 | 1089 | |
5e96b616 | 1090 | if ((control_fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) |
1091 | fatal("%s socket(): %s\n", __func__, strerror(errno)); | |
1092 | ||
1093 | old_umask = umask(0177); | |
4b5df124 | 1094 | if (bind(control_fd, (struct sockaddr*)&addr, addr_len) == -1) { |
5e96b616 | 1095 | control_fd = -1; |
1096 | if (errno == EINVAL) | |
1097 | fatal("ControlSocket %s already exists", | |
1098 | options.control_path); | |
1099 | else | |
1100 | fatal("%s bind(): %s\n", __func__, strerror(errno)); | |
8ce64345 | 1101 | } |
5e96b616 | 1102 | umask(old_umask); |
1103 | ||
1104 | if (listen(control_fd, 64) == -1) | |
1105 | fatal("%s listen(): %s\n", __func__, strerror(errno)); | |
1106 | ||
1107 | set_nonblock(control_fd); | |
1108 | } | |
1109 | ||
1110 | /* request pty/x11/agent/tcpfwd/shell for channel */ | |
1111 | static void | |
1112 | ssh_session2_setup(int id, void *arg) | |
1113 | { | |
1786be35 | 1114 | extern char **environ; |
1115 | ||
5e96b616 | 1116 | int interactive = tty_flag; |
1117 | if (options.forward_x11 && getenv("DISPLAY") != NULL) { | |
b48eeb07 | 1118 | char *proto, *data; |
0b242b12 | 1119 | /* Get reasonable local authentication information. */ |
b48eeb07 | 1120 | x11_get_proto(&proto, &data); |
0b242b12 | 1121 | /* Request forwarding with authentication spoofing. */ |
1122 | debug("Requesting X11 forwarding with authentication spoofing."); | |
1123 | x11_request_forwarding_with_spoofing(id, proto, data); | |
b5c334cc | 1124 | interactive = 1; |
0b242b12 | 1125 | /* XXX wait for reply */ |
1126 | } | |
1127 | ||
fa08c86b | 1128 | check_agent_present(); |
1129 | if (options.forward_agent) { | |
1130 | debug("Requesting authentication agent forwarding."); | |
1131 | channel_request_start(id, "auth-agent-req@openssh.com", 0); | |
1132 | packet_send(); | |
1133 | } | |
1134 | ||
5e96b616 | 1135 | client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"), |
1786be35 | 1136 | NULL, fileno(stdin), &command, environ, &ssh_subsystem_reply); |
1f3bf5aa | 1137 | |
b5c334cc | 1138 | packet_set_interactive(interactive); |
8ce64345 | 1139 | } |
1140 | ||
bcdb96c2 | 1141 | /* open new channel for a session */ |
396c147e | 1142 | static int |
bcdb96c2 | 1143 | ssh_session2_open(void) |
8ce64345 | 1144 | { |
719fc62f | 1145 | Channel *c; |
1146 | int window, packetmax, in, out, err; | |
2e73a022 | 1147 | |
14a9a859 | 1148 | if (stdin_null_flag) { |
5ca51e19 | 1149 | in = open(_PATH_DEVNULL, O_RDONLY); |
14a9a859 | 1150 | } else { |
1151 | in = dup(STDIN_FILENO); | |
1152 | } | |
2e73a022 | 1153 | out = dup(STDOUT_FILENO); |
1154 | err = dup(STDERR_FILENO); | |
8ce64345 | 1155 | |
1156 | if (in < 0 || out < 0 || err < 0) | |
14a9a859 | 1157 | fatal("dup() in/out/err failed"); |
8ce64345 | 1158 | |
a22aff1f | 1159 | /* enable nonblocking unless tty */ |
1160 | if (!isatty(in)) | |
1161 | set_nonblock(in); | |
1162 | if (!isatty(out)) | |
1163 | set_nonblock(out); | |
1164 | if (!isatty(err)) | |
1165 | set_nonblock(err); | |
1166 | ||
bcbf86ec | 1167 | window = CHAN_SES_WINDOW_DEFAULT; |
1168 | packetmax = CHAN_SES_PACKET_DEFAULT; | |
ea9700ba | 1169 | if (tty_flag) { |
1170 | window >>= 1; | |
1171 | packetmax >>= 1; | |
8ce64345 | 1172 | } |
719fc62f | 1173 | c = channel_new( |
8ce64345 | 1174 | "session", SSH_CHANNEL_OPENING, in, out, err, |
bcbf86ec | 1175 | window, packetmax, CHAN_EXTENDED_WRITE, |
0d942eff | 1176 | "client-session", /*nonblock*/0); |
8ce64345 | 1177 | |
bcdb96c2 | 1178 | debug3("ssh_session2_open: channel_new: %d", c->self); |
eb0dd41f | 1179 | |
36e1f6a1 | 1180 | channel_send_open(c->self); |
bcdb96c2 | 1181 | if (!no_shell_flag) |
5e96b616 | 1182 | channel_register_confirm(c->self, ssh_session2_setup, NULL); |
5260325f | 1183 | |
719fc62f | 1184 | return c->self; |
eb0dd41f | 1185 | } |
1186 | ||
396c147e | 1187 | static int |
eb0dd41f | 1188 | ssh_session2(void) |
1189 | { | |
bcdb96c2 | 1190 | int id = -1; |
eb0dd41f | 1191 | |
1192 | /* XXX should be pre-session */ | |
1193 | ssh_init_forwarding(); | |
5e96b616 | 1194 | ssh_control_listener(); |
eb0dd41f | 1195 | |
bcdb96c2 | 1196 | if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN)) |
1197 | id = ssh_session2_open(); | |
eb0dd41f | 1198 | |
1199 | /* If requested, let ssh continue in the background. */ | |
1200 | if (fork_after_authentication_flag) | |
1201 | if (daemon(1, 1) < 0) | |
1202 | fatal("daemon() failed: %.200s", strerror(errno)); | |
1203 | ||
4bf9c10e | 1204 | return client_loop(tty_flag, tty_flag ? |
1205 | options.escape_char : SSH_ESCAPECHAR_NONE, id); | |
8efc0c15 | 1206 | } |
fa08c86b | 1207 | |
396c147e | 1208 | static void |
fee56204 | 1209 | load_public_identity_files(void) |
1210 | { | |
1211 | char *filename; | |
2e23cde0 | 1212 | int i = 0; |
0659cace | 1213 | Key *public; |
383546c4 | 1214 | #ifdef SMARTCARD |
0659cace | 1215 | Key **keys; |
1216 | ||
9ff6f66f | 1217 | if (options.smartcard_device != NULL && |
0659cace | 1218 | options.num_identity_files < SSH_MAX_IDENTITY_FILES && |
1219 | (keys = sc_get_keys(options.smartcard_device, NULL)) != NULL ) { | |
1220 | int count = 0; | |
1221 | for (i = 0; keys[i] != NULL; i++) { | |
1222 | count++; | |
0659cace | 1223 | memmove(&options.identity_files[1], &options.identity_files[0], |
1224 | sizeof(char *) * (SSH_MAX_IDENTITY_FILES - 1)); | |
1225 | memmove(&options.identity_keys[1], &options.identity_keys[0], | |
1226 | sizeof(Key *) * (SSH_MAX_IDENTITY_FILES - 1)); | |
1227 | options.num_identity_files++; | |
1228 | options.identity_keys[0] = keys[i]; | |
244e796f | 1229 | options.identity_files[0] = sc_get_key_label(keys[i]); |
0659cace | 1230 | } |
1c2deed1 | 1231 | if (options.num_identity_files > SSH_MAX_IDENTITY_FILES) |
1232 | options.num_identity_files = SSH_MAX_IDENTITY_FILES; | |
0659cace | 1233 | i = count; |
1234 | xfree(keys); | |
383546c4 | 1235 | } |
3e984472 | 1236 | #endif /* SMARTCARD */ |
2e23cde0 | 1237 | for (; i < options.num_identity_files; i++) { |
1238 | filename = tilde_expand_filename(options.identity_files[i], | |
1239 | original_real_uid); | |
1240 | public = key_load_public(filename, NULL); | |
1241 | debug("identity file %s type %d", filename, | |
1242 | public ? public->type : -1); | |
1243 | xfree(options.identity_files[i]); | |
1244 | options.identity_files[i] = filename; | |
1245 | options.identity_keys[i] = public; | |
1246 | } | |
fee56204 | 1247 | } |
5e96b616 | 1248 | |
1249 | static void | |
1250 | control_client_sighandler(int signo) | |
1251 | { | |
1252 | control_client_terminate = signo; | |
1253 | } | |
1254 | ||
1255 | static void | |
1256 | control_client_sigrelay(int signo) | |
1257 | { | |
1258 | if (control_server_pid > 1) | |
1259 | kill(control_server_pid, signo); | |
1260 | } | |
1261 | ||
67a08279 | 1262 | static int |
1263 | env_permitted(char *env) | |
1264 | { | |
1265 | int i; | |
1266 | char name[1024], *cp; | |
1267 | ||
1268 | strlcpy(name, env, sizeof(name)); | |
1269 | if ((cp = strchr(name, '=')) == NULL) | |
1270 | return (0); | |
1271 | ||
1272 | *cp = '\0'; | |
1273 | ||
1274 | for (i = 0; i < options.num_send_env; i++) | |
1275 | if (match_pattern(name, options.send_env[i])) | |
1276 | return (1); | |
1277 | ||
1278 | return (0); | |
1279 | } | |
1280 | ||
5e96b616 | 1281 | static void |
1282 | control_client(const char *path) | |
1283 | { | |
1284 | struct sockaddr_un addr; | |
a7e124fe | 1285 | int i, r, fd, sock, exitval, num_env, addr_len; |
5e96b616 | 1286 | Buffer m; |
f8c6db83 | 1287 | char *term; |
1786be35 | 1288 | extern char **environ; |
f8c6db83 | 1289 | u_int flags; |
f2107e97 | 1290 | |
a7e124fe | 1291 | if (stdin_null_flag) { |
1292 | if ((fd = open(_PATH_DEVNULL, O_RDONLY)) == -1) | |
1293 | fatal("open(/dev/null): %s", strerror(errno)); | |
1294 | if (dup2(fd, STDIN_FILENO) == -1) | |
1295 | fatal("dup2: %s", strerror(errno)); | |
1296 | if (fd > STDERR_FILENO) | |
1297 | close(fd); | |
1298 | } | |
1299 | ||
5e96b616 | 1300 | memset(&addr, '\0', sizeof(addr)); |
1301 | addr.sun_family = AF_UNIX; | |
4b5df124 | 1302 | addr_len = offsetof(struct sockaddr_un, sun_path) + |
5e96b616 | 1303 | strlen(path) + 1; |
1304 | ||
1305 | if (strlcpy(addr.sun_path, path, | |
1306 | sizeof(addr.sun_path)) >= sizeof(addr.sun_path)) | |
1307 | fatal("ControlPath too long"); | |
1308 | ||
1309 | if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) | |
1310 | fatal("%s socket(): %s", __func__, strerror(errno)); | |
1311 | ||
4b5df124 | 1312 | if (connect(sock, (struct sockaddr*)&addr, addr_len) == -1) |
5e96b616 | 1313 | fatal("Couldn't connect to %s: %s", path, strerror(errno)); |
1314 | ||
f8c6db83 | 1315 | if ((term = getenv("TERM")) == NULL) |
1316 | term = ""; | |
1317 | ||
1318 | flags = 0; | |
1319 | if (tty_flag) | |
1320 | flags |= SSHMUX_FLAG_TTY; | |
1321 | if (subsystem_flag) | |
1322 | flags |= SSHMUX_FLAG_SUBSYS; | |
5e96b616 | 1323 | |
5e96b616 | 1324 | buffer_init(&m); |
1325 | ||
f8c6db83 | 1326 | /* Send our command to server */ |
1327 | buffer_put_int(&m, mux_command); | |
1328 | buffer_put_int(&m, flags); | |
1329 | if (ssh_msg_send(sock, /* version */1, &m) == -1) | |
1330 | fatal("%s: msg_send", __func__); | |
1331 | buffer_clear(&m); | |
1332 | ||
1333 | /* Get authorisation status and PID of controlee */ | |
5e96b616 | 1334 | if (ssh_msg_recv(sock, &m) == -1) |
1335 | fatal("%s: msg_recv", __func__); | |
f8c6db83 | 1336 | if (buffer_get_char(&m) != 1) |
5e96b616 | 1337 | fatal("%s: wrong version", __func__); |
0d34d6ce | 1338 | if (buffer_get_int(&m) != 1) |
1339 | fatal("Connection to master denied"); | |
5e96b616 | 1340 | control_server_pid = buffer_get_int(&m); |
1341 | ||
5e96b616 | 1342 | buffer_clear(&m); |
5e96b616 | 1343 | |
f8c6db83 | 1344 | switch (mux_command) { |
1345 | case SSHMUX_COMMAND_ALIVE_CHECK: | |
1346 | fprintf(stderr, "Master running (pid=%d)\r\n", | |
1347 | control_server_pid); | |
1348 | exit(0); | |
1349 | case SSHMUX_COMMAND_TERMINATE: | |
1350 | fprintf(stderr, "Exit request sent.\r\n"); | |
1351 | exit(0); | |
1352 | case SSHMUX_COMMAND_OPEN: | |
1353 | /* continue below */ | |
1354 | break; | |
1355 | default: | |
1356 | fatal("silly mux_command %d", mux_command); | |
1357 | } | |
1358 | ||
1359 | /* SSHMUX_COMMAND_OPEN */ | |
1360 | buffer_put_cstring(&m, term); | |
5e96b616 | 1361 | buffer_append(&command, "\0", 1); |
1362 | buffer_put_cstring(&m, buffer_ptr(&command)); | |
1363 | ||
67a08279 | 1364 | if (options.num_send_env == 0 || environ == NULL) { |
1365 | buffer_put_int(&m, 0); | |
f2107e97 | 1366 | } else { |
67a08279 | 1367 | /* Pass environment */ |
1368 | num_env = 0; | |
1369 | for (i = 0; environ[i] != NULL; i++) | |
1370 | if (env_permitted(environ[i])) | |
1371 | num_env++; /* Count */ | |
f2107e97 | 1372 | |
67a08279 | 1373 | buffer_put_int(&m, num_env); |
1374 | ||
77c50919 | 1375 | for (i = 0; environ[i] != NULL && num_env >= 0; i++) |
1376 | if (env_permitted(environ[i])) { | |
1377 | num_env--; | |
67a08279 | 1378 | buffer_put_cstring(&m, environ[i]); |
77c50919 | 1379 | } |
67a08279 | 1380 | } |
1786be35 | 1381 | |
f8c6db83 | 1382 | if (ssh_msg_send(sock, /* version */1, &m) == -1) |
5e96b616 | 1383 | fatal("%s: msg_send", __func__); |
1384 | ||
1385 | mm_send_fd(sock, STDIN_FILENO); | |
1386 | mm_send_fd(sock, STDOUT_FILENO); | |
1387 | mm_send_fd(sock, STDERR_FILENO); | |
1388 | ||
1389 | /* Wait for reply, so master has a chance to gather ttymodes */ | |
1390 | buffer_clear(&m); | |
1391 | if (ssh_msg_recv(sock, &m) == -1) | |
1392 | fatal("%s: msg_recv", __func__); | |
f8c6db83 | 1393 | if (buffer_get_char(&m) != 1) |
1394 | fatal("%s: wrong version", __func__); | |
5e96b616 | 1395 | buffer_free(&m); |
1396 | ||
d3e5d1e9 | 1397 | signal(SIGHUP, control_client_sighandler); |
78d2b454 | 1398 | signal(SIGINT, control_client_sighandler); |
1399 | signal(SIGTERM, control_client_sighandler); | |
1400 | signal(SIGWINCH, control_client_sigrelay); | |
1401 | ||
5e96b616 | 1402 | if (tty_flag) |
1403 | enter_raw_mode(); | |
1404 | ||
1405 | /* Stick around until the controlee closes the client_fd */ | |
1406 | exitval = 0; | |
1407 | for (;!control_client_terminate;) { | |
1408 | r = read(sock, &exitval, sizeof(exitval)); | |
1409 | if (r == 0) { | |
1410 | debug2("Received EOF from master"); | |
1411 | break; | |
1412 | } | |
1413 | if (r > 0) | |
1414 | debug2("Received exit status from master %d", exitval); | |
1415 | if (r == -1 && errno != EINTR) | |
1416 | fatal("%s: read %s", __func__, strerror(errno)); | |
1417 | } | |
1418 | ||
1419 | if (control_client_terminate) | |
1420 | debug2("Exiting on signal %d", control_client_terminate); | |
1421 | ||
1422 | close(sock); | |
1423 | ||
1424 | leave_raw_mode(); | |
1425 | ||
1426 | if (tty_flag && options.log_level != SYSLOG_LEVEL_QUIET) | |
1427 | fprintf(stderr, "Connection to master closed.\r\n"); | |
1428 | ||
1429 | exit(exitval); | |
1430 | } |