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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" | |
f8c6db83 | 43 | RCSID("$OpenBSD: ssh.c,v 1.229 2004/11/07 00:01:46 djm 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, |
0e19494c | 160 | "usage: ssh [-1246AaCfghkMNnqsTtVvXxY] [-b bind_address] [-c cipher_spec]\n" |
182ccbba | 161 | " [-D port] [-e escape_char] [-F configfile] [-i identity_file]\n" |
162 | " [-L port:host:hostport] [-l login_name] [-m mac_spec] [-o option]\n" | |
4598add7 | 163 | " [-p port] [-R port:host:hostport] [-S ctl] [user@]hostname [command]\n" |
182ccbba | 164 | ); |
5260325f | 165 | exit(1); |
8efc0c15 | 166 | } |
167 | ||
396c147e | 168 | static int ssh_session(void); |
169 | static int ssh_session2(void); | |
170 | static void load_public_identity_files(void); | |
5e96b616 | 171 | static void control_client(const char *path); |
8ce64345 | 172 | |
5260325f | 173 | /* |
174 | * Main program for the ssh client. | |
175 | */ | |
8efc0c15 | 176 | int |
177 | main(int ac, char **av) | |
178 | { | |
b34bec32 | 179 | int i, opt, exit_status; |
57112b5a | 180 | u_short fwd_port, fwd_host_port; |
d2e3df16 | 181 | char sfwd_port[6], sfwd_host_port[6]; |
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; |
5260325f | 188 | |
fda04d7d | 189 | __progname = ssh_get_progname(av[0]); |
264dce47 | 190 | init_rng(); |
191 | ||
aa3378df | 192 | /* |
193 | * Save the original real uid. It will be needed later (uid-swapping | |
194 | * may clobber the real uid). | |
195 | */ | |
5260325f | 196 | original_real_uid = getuid(); |
197 | original_effective_uid = geteuid(); | |
aff51935 | 198 | |
9f324470 | 199 | /* |
200 | * Use uid-swapping to give up root privileges for the duration of | |
201 | * option processing. We will re-instantiate the rights when we are | |
202 | * ready to create the privileged port, and will permanently drop | |
203 | * them when the port has been created (actually, when the connection | |
204 | * has been made, as we may need to create the port several times). | |
205 | */ | |
206 | PRIV_END; | |
5260325f | 207 | |
7322ef0e | 208 | #ifdef HAVE_SETRLIMIT |
5260325f | 209 | /* If we are installed setuid root be careful to not drop core. */ |
210 | if (original_real_uid != original_effective_uid) { | |
211 | struct rlimit rlim; | |
212 | rlim.rlim_cur = rlim.rlim_max = 0; | |
213 | if (setrlimit(RLIMIT_CORE, &rlim) < 0) | |
214 | fatal("setrlimit failed: %.100s", strerror(errno)); | |
8efc0c15 | 215 | } |
3c62e7eb | 216 | #endif |
63bd8c36 | 217 | /* Get user data. */ |
218 | pw = getpwuid(original_real_uid); | |
219 | if (!pw) { | |
bbe88b6d | 220 | logit("You don't exist, go away!"); |
63bd8c36 | 221 | exit(1); |
222 | } | |
223 | /* Take a copy of the returned structure. */ | |
224 | pw = pwcopy(pw); | |
225 | ||
aa3378df | 226 | /* |
227 | * Set our umask to something reasonable, as some files are created | |
228 | * with the default umask. This will make them world-readable but | |
229 | * writable only by the owner, which is ok for all files for which we | |
230 | * don't set the modes explicitly. | |
231 | */ | |
5260325f | 232 | umask(022); |
233 | ||
5260325f | 234 | /* Initialize option structure to indicate that no values have been set. */ |
235 | initialize_options(&options); | |
236 | ||
237 | /* Parse command-line arguments. */ | |
238 | host = NULL; | |
239 | ||
f5a1a01a | 240 | again: |
241 | while ((opt = getopt(ac, av, | |
f8c6db83 | 242 | "1246ab:c:e:fgi:kl:m:no:p:qstvxACD:F:I:L:MNO:PR:S:TVXY")) != -1) { |
5260325f | 243 | switch (opt) { |
1f3bf5aa | 244 | case '1': |
245 | options.protocol = SSH_PROTO_1; | |
246 | break; | |
6ae2364d | 247 | case '2': |
248 | options.protocol = SSH_PROTO_2; | |
249 | break; | |
48e671d5 | 250 | case '4': |
1572b90f | 251 | options.address_family = AF_INET; |
48e671d5 | 252 | break; |
48e671d5 | 253 | case '6': |
1572b90f | 254 | options.address_family = AF_INET6; |
48e671d5 | 255 | break; |
5260325f | 256 | case 'n': |
257 | stdin_null_flag = 1; | |
258 | break; | |
5260325f | 259 | case 'f': |
260 | fork_after_authentication_flag = 1; | |
261 | stdin_null_flag = 1; | |
262 | break; | |
5260325f | 263 | case 'x': |
264 | options.forward_x11 = 0; | |
265 | break; | |
5260325f | 266 | case 'X': |
267 | options.forward_x11 = 1; | |
268 | break; | |
d73a67d7 | 269 | case 'Y': |
270 | options.forward_x11 = 1; | |
271 | options.forward_x11_trusted = 1; | |
272 | break; | |
5260325f | 273 | case 'g': |
274 | options.gateway_ports = 1; | |
275 | break; | |
f8c6db83 | 276 | case 'O': |
277 | if (strcmp(optarg, "check") == 0) | |
278 | mux_command = SSHMUX_COMMAND_ALIVE_CHECK; | |
279 | else if (strcmp(optarg, "exit") == 0) | |
280 | mux_command = SSHMUX_COMMAND_TERMINATE; | |
281 | else | |
282 | fatal("Invalid multiplex command."); | |
283 | break; | |
e59404d1 | 284 | case 'P': /* deprecated */ |
5260325f | 285 | options.use_privileged_port = 0; |
286 | break; | |
5260325f | 287 | case 'a': |
288 | options.forward_agent = 0; | |
289 | break; | |
71276795 | 290 | case 'A': |
291 | options.forward_agent = 1; | |
292 | break; | |
5260325f | 293 | case 'k': |
f7926e97 | 294 | options.gss_deleg_creds = 0; |
5260325f | 295 | break; |
5260325f | 296 | case 'i': |
297 | if (stat(optarg, &st) < 0) { | |
f5a1a01a | 298 | fprintf(stderr, "Warning: Identity file %s " |
299 | "does not exist.\n", optarg); | |
5260325f | 300 | break; |
301 | } | |
f5a1a01a | 302 | if (options.num_identity_files >= |
303 | SSH_MAX_IDENTITY_FILES) | |
304 | fatal("Too many identity files specified " | |
305 | "(max %d)", SSH_MAX_IDENTITY_FILES); | |
306 | options.identity_files[options.num_identity_files++] = | |
307 | xstrdup(optarg); | |
5260325f | 308 | break; |
383546c4 | 309 | case 'I': |
310 | #ifdef SMARTCARD | |
9ff6f66f | 311 | options.smartcard_device = xstrdup(optarg); |
dd2495cb | 312 | #else |
383546c4 | 313 | fprintf(stderr, "no support for smartcards.\n"); |
dd2495cb | 314 | #endif |
383546c4 | 315 | break; |
5260325f | 316 | case 't': |
8abcdba4 | 317 | if (tty_flag) |
318 | force_tty_flag = 1; | |
5260325f | 319 | tty_flag = 1; |
320 | break; | |
5260325f | 321 | case 'v': |
e053cd2c | 322 | if (debug_flag == 0) { |
bcbf86ec | 323 | debug_flag = 1; |
324 | options.log_level = SYSLOG_LEVEL_DEBUG1; | |
e053cd2c | 325 | } else { |
326 | if (options.log_level < SYSLOG_LEVEL_DEBUG3) | |
327 | options.log_level++; | |
bcbf86ec | 328 | break; |
e053cd2c | 329 | } |
59d4718a | 330 | /* FALLTHROUGH */ |
5260325f | 331 | case 'V': |
85ac7a84 | 332 | fprintf(stderr, "%s, %s\n", |
4526e8c2 | 333 | SSH_RELEASE, SSLeay_version(SSLEAY_VERSION)); |
5260325f | 334 | if (opt == 'V') |
335 | exit(0); | |
5260325f | 336 | break; |
5260325f | 337 | case 'q': |
338 | options.log_level = SYSLOG_LEVEL_QUIET; | |
339 | break; | |
5260325f | 340 | case 'e': |
341 | if (optarg[0] == '^' && optarg[2] == 0 && | |
f5a1a01a | 342 | (u_char) optarg[1] >= 64 && |
343 | (u_char) optarg[1] < 128) | |
1e3b8b07 | 344 | options.escape_char = (u_char) optarg[1] & 31; |
5260325f | 345 | else if (strlen(optarg) == 1) |
1e3b8b07 | 346 | options.escape_char = (u_char) optarg[0]; |
5260325f | 347 | else if (strcmp(optarg, "none") == 0) |
4bf9c10e | 348 | options.escape_char = SSH_ESCAPECHAR_NONE; |
5260325f | 349 | else { |
f5a1a01a | 350 | fprintf(stderr, "Bad escape character '%s'.\n", |
351 | optarg); | |
5260325f | 352 | exit(1); |
353 | } | |
354 | break; | |
5260325f | 355 | case 'c': |
a306f2dd | 356 | if (ciphers_valid(optarg)) { |
357 | /* SSH2 only */ | |
358 | options.ciphers = xstrdup(optarg); | |
d77347cc | 359 | options.cipher = SSH_CIPHER_INVALID; |
a306f2dd | 360 | } else { |
361 | /* SSH1 only */ | |
c523303b | 362 | options.cipher = cipher_number(optarg); |
363 | if (options.cipher == -1) { | |
f5a1a01a | 364 | fprintf(stderr, |
365 | "Unknown cipher type '%s'\n", | |
366 | optarg); | |
a306f2dd | 367 | exit(1); |
368 | } | |
f5a1a01a | 369 | if (options.cipher == SSH_CIPHER_3DES) |
c523303b | 370 | options.ciphers = "3des-cbc"; |
f5a1a01a | 371 | else if (options.cipher == SSH_CIPHER_BLOWFISH) |
c523303b | 372 | options.ciphers = "blowfish-cbc"; |
f5a1a01a | 373 | else |
c523303b | 374 | options.ciphers = (char *)-1; |
5260325f | 375 | } |
376 | break; | |
b2552997 | 377 | case 'm': |
378 | if (mac_valid(optarg)) | |
379 | options.macs = xstrdup(optarg); | |
380 | else { | |
f5a1a01a | 381 | fprintf(stderr, "Unknown mac type '%s'\n", |
382 | optarg); | |
b2552997 | 383 | exit(1); |
384 | } | |
385 | break; | |
5e96b616 | 386 | case 'M': |
4598add7 | 387 | options.control_master = |
388 | (options.control_master >= 1) ? 2 : 1; | |
5e96b616 | 389 | break; |
5260325f | 390 | case 'p': |
2d2a2c65 | 391 | options.port = a2port(optarg); |
392 | if (options.port == 0) { | |
6031af8d | 393 | fprintf(stderr, "Bad port '%s'\n", optarg); |
394 | exit(1); | |
395 | } | |
5260325f | 396 | break; |
5260325f | 397 | case 'l': |
398 | options.user = optarg; | |
399 | break; | |
d2e3df16 | 400 | |
401 | case 'L': | |
5260325f | 402 | case 'R': |
fa065de2 | 403 | if (sscanf(optarg, "%5[0123456789]:%255[^:]:%5[0123456789]", |
d2e3df16 | 404 | sfwd_port, buf, sfwd_host_port) != 3 && |
fa065de2 | 405 | sscanf(optarg, "%5[0123456789]/%255[^/]/%5[0123456789]", |
d2e3df16 | 406 | sfwd_port, buf, sfwd_host_port) != 3) { |
f5a1a01a | 407 | fprintf(stderr, |
d2e3df16 | 408 | "Bad forwarding specification '%s'\n", |
f5a1a01a | 409 | optarg); |
5260325f | 410 | usage(); |
411 | /* NOTREACHED */ | |
412 | } | |
d2e3df16 | 413 | if ((fwd_port = a2port(sfwd_port)) == 0 || |
762715ce | 414 | (fwd_host_port = a2port(sfwd_host_port)) == 0) { |
f5a1a01a | 415 | fprintf(stderr, |
d2e3df16 | 416 | "Bad forwarding port(s) '%s'\n", optarg); |
417 | exit(1); | |
5260325f | 418 | } |
d2e3df16 | 419 | if (opt == 'L') |
420 | add_local_forward(&options, fwd_port, buf, | |
421 | fwd_host_port); | |
422 | else if (opt == 'R') | |
423 | add_remote_forward(&options, fwd_port, buf, | |
184eed6a | 424 | fwd_host_port); |
5260325f | 425 | break; |
0490e609 | 426 | |
427 | case 'D': | |
2d2a2c65 | 428 | fwd_port = a2port(optarg); |
429 | if (fwd_port == 0) { | |
f5a1a01a | 430 | fprintf(stderr, "Bad dynamic port '%s'\n", |
431 | optarg); | |
6031af8d | 432 | exit(1); |
433 | } | |
37ba5172 | 434 | add_local_forward(&options, fwd_port, "socks", 0); |
0490e609 | 435 | break; |
436 | ||
5260325f | 437 | case 'C': |
438 | options.compression = 1; | |
439 | break; | |
8ce64345 | 440 | case 'N': |
441 | no_shell_flag = 1; | |
442 | no_tty_flag = 1; | |
443 | break; | |
8ce64345 | 444 | case 'T': |
445 | no_tty_flag = 1; | |
446 | break; | |
5260325f | 447 | case 'o': |
448 | dummy = 1; | |
1aafd17a | 449 | line = xstrdup(optarg); |
f5a1a01a | 450 | if (process_config_line(&options, host ? host : "", |
1aafd17a | 451 | line, "command-line", 0, &dummy) != 0) |
5260325f | 452 | exit(1); |
1aafd17a | 453 | xfree(line); |
5260325f | 454 | break; |
ae810de7 | 455 | case 's': |
456 | subsystem_flag = 1; | |
457 | break; | |
5e96b616 | 458 | case 'S': |
459 | if (options.control_path != NULL) | |
460 | free(options.control_path); | |
461 | options.control_path = xstrdup(optarg); | |
5e96b616 | 462 | break; |
3435f5a6 | 463 | case 'b': |
464 | options.bind_address = optarg; | |
465 | break; | |
e591b98a | 466 | case 'F': |
467 | config = optarg; | |
468 | break; | |
5260325f | 469 | default: |
470 | usage(); | |
471 | } | |
472 | } | |
473 | ||
f5a1a01a | 474 | ac -= optind; |
475 | av += optind; | |
476 | ||
477 | if (ac > 0 && !host && **av != '-') { | |
15748b4d | 478 | if (strrchr(*av, '@')) { |
f5a1a01a | 479 | p = xstrdup(*av); |
15748b4d | 480 | cp = strrchr(p, '@'); |
f5a1a01a | 481 | if (cp == NULL || cp == p) |
482 | usage(); | |
483 | options.user = p; | |
484 | *cp = '\0'; | |
485 | host = ++cp; | |
486 | } else | |
487 | host = *av; | |
978ebf99 | 488 | if (ac > 1) { |
489 | optind = optreset = 1; | |
f5a1a01a | 490 | goto again; |
491 | } | |
978ebf99 | 492 | ac--, av++; |
f5a1a01a | 493 | } |
494 | ||
5260325f | 495 | /* Check that we got a host name. */ |
496 | if (!host) | |
8efc0c15 | 497 | usage(); |
5260325f | 498 | |
22d89d24 | 499 | SSLeay_add_all_algorithms(); |
fa08c86b | 500 | ERR_load_crypto_strings(); |
22d89d24 | 501 | |
5260325f | 502 | /* Initialize the command to execute on remote host. */ |
503 | buffer_init(&command); | |
504 | ||
aa3378df | 505 | /* |
506 | * Save the command to execute on the remote host in a buffer. There | |
507 | * is no limit on the length of the command, except by the maximum | |
508 | * packet size. Also sets the tty flag if there is no command. | |
509 | */ | |
f5a1a01a | 510 | if (!ac) { |
5260325f | 511 | /* No command specified - execute shell on a tty. */ |
512 | tty_flag = 1; | |
ae810de7 | 513 | if (subsystem_flag) { |
f5a1a01a | 514 | fprintf(stderr, |
515 | "You must specify a subsystem to invoke.\n"); | |
ae810de7 | 516 | usage(); |
517 | } | |
5260325f | 518 | } else { |
f5a1a01a | 519 | /* A command has been specified. Store it into the buffer. */ |
520 | for (i = 0; i < ac; i++) { | |
521 | if (i) | |
5260325f | 522 | buffer_append(&command, " ", 1); |
523 | buffer_append(&command, av[i], strlen(av[i])); | |
524 | } | |
8efc0c15 | 525 | } |
5260325f | 526 | |
527 | /* Cannot fork to background if no command. */ | |
14a9a859 | 528 | if (fork_after_authentication_flag && buffer_len(&command) == 0 && !no_shell_flag) |
5260325f | 529 | fatal("Cannot fork into background without a command to execute."); |
530 | ||
531 | /* Allocate a tty by default if no command specified. */ | |
532 | if (buffer_len(&command) == 0) | |
533 | tty_flag = 1; | |
534 | ||
343288b8 | 535 | /* Force no tty */ |
0b6fbf03 | 536 | if (no_tty_flag) |
537 | tty_flag = 0; | |
5260325f | 538 | /* Do not allocate a tty if stdin is not a tty. */ |
8abcdba4 | 539 | if (!isatty(fileno(stdin)) && !force_tty_flag) { |
5260325f | 540 | if (tty_flag) |
bbe88b6d | 541 | logit("Pseudo-terminal will not be allocated because stdin is not a terminal."); |
5260325f | 542 | tty_flag = 0; |
543 | } | |
8ce64345 | 544 | |
20244695 | 545 | /* |
546 | * Initialize "log" output. Since we are the client all output | |
547 | * actually goes to stderr. | |
548 | */ | |
cc44f691 | 549 | log_init(av[0], options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level, |
550 | SYSLOG_FACILITY_USER, 1); | |
5260325f | 551 | |
e591b98a | 552 | /* |
553 | * Read per-user configuration file. Ignore the system wide config | |
554 | * file if the user specifies a config file on the command line. | |
555 | */ | |
556 | if (config != NULL) { | |
f7f14143 | 557 | if (!read_config_file(config, host, &options, 0)) |
93111dfa | 558 | fatal("Can't open user config file %.100s: " |
559 | "%.100s", config, strerror(errno)); | |
e591b98a | 560 | } else { |
561 | snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, | |
562 | _PATH_SSH_USER_CONFFILE); | |
9f6cab4b | 563 | (void)read_config_file(buf, host, &options, 1); |
e591b98a | 564 | |
f67792f2 | 565 | /* Read systemwide configuration file after use config. */ |
f2107e97 | 566 | (void)read_config_file(_PATH_HOST_CONFIG_FILE, host, |
9f6cab4b | 567 | &options, 0); |
e591b98a | 568 | } |
5260325f | 569 | |
570 | /* Fill configuration defaults. */ | |
571 | fill_default_options(&options); | |
572 | ||
1572b90f | 573 | channel_set_af(options.address_family); |
574 | ||
5260325f | 575 | /* reinit */ |
20244695 | 576 | log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, 1); |
5260325f | 577 | |
e339aa53 | 578 | seed_rng(); |
579 | ||
5260325f | 580 | if (options.user == NULL) |
581 | options.user = xstrdup(pw->pw_name); | |
582 | ||
583 | if (options.hostname != NULL) | |
584 | host = options.hostname; | |
585 | ||
03c82656 | 586 | /* force lowercase for hostkey matching */ |
587 | if (options.host_key_alias != NULL) { | |
588 | for (p = options.host_key_alias; *p; p++) | |
589 | if (isupper(*p)) | |
590 | *p = tolower(*p); | |
591 | } | |
592 | ||
f78bde70 | 593 | if (options.proxy_command != NULL && |
594 | strcmp(options.proxy_command, "none") == 0) | |
595 | options.proxy_command = NULL; | |
596 | ||
5e96b616 | 597 | if (options.control_path != NULL) { |
598 | options.control_path = tilde_expand_filename( | |
599 | options.control_path, original_real_uid); | |
600 | } | |
601 | if (options.control_path != NULL && options.control_master == 0) | |
602 | control_client(options.control_path); /* This doesn't return */ | |
603 | ||
6ffc9c88 | 604 | /* Open a connection to the remote host. */ |
1572b90f | 605 | if (ssh_connect(host, &hostaddr, options.port, |
606 | options.address_family, options.connection_attempts, | |
d514c907 | 607 | #ifdef HAVE_CYGWIN |
608 | options.use_privileged_port, | |
609 | #else | |
3fb156df | 610 | original_effective_uid == 0 && options.use_privileged_port, |
d514c907 | 611 | #endif |
de60473e | 612 | options.proxy_command) != 0) |
b34bec32 | 613 | exit(1); |
5260325f | 614 | |
aa3378df | 615 | /* |
616 | * If we successfully made the connection, load the host private key | |
617 | * in case we will need it later for combined rsa-rhosts | |
618 | * authentication. This must be done before releasing extra | |
619 | * privileges, because the file is only readable by root. | |
78660ed4 | 620 | * If we cannot access the private keys, load the public keys |
621 | * instead and try to execute the ssh-keysign helper instead. | |
aa3378df | 622 | */ |
8002af61 | 623 | sensitive_data.nkeys = 0; |
624 | sensitive_data.keys = NULL; | |
39c00dc2 | 625 | sensitive_data.external_keysign = 0; |
b34bec32 | 626 | if (options.rhosts_rsa_authentication || |
627 | options.hostbased_authentication) { | |
8002af61 | 628 | sensitive_data.nkeys = 3; |
343288b8 | 629 | sensitive_data.keys = xmalloc(sensitive_data.nkeys * |
630 | sizeof(Key)); | |
3fb156df | 631 | |
632 | PRIV_START; | |
8002af61 | 633 | sensitive_data.keys[0] = key_load_private_type(KEY_RSA1, |
aeaa3d9e | 634 | _PATH_HOST_KEY_FILE, "", NULL); |
8002af61 | 635 | sensitive_data.keys[1] = key_load_private_type(KEY_DSA, |
636 | _PATH_HOST_DSA_KEY_FILE, "", NULL); | |
637 | sensitive_data.keys[2] = key_load_private_type(KEY_RSA, | |
638 | _PATH_HOST_RSA_KEY_FILE, "", NULL); | |
3fb156df | 639 | PRIV_END; |
39c00dc2 | 640 | |
60cd0a97 | 641 | if (options.hostbased_authentication == 1 && |
642 | sensitive_data.keys[0] == NULL && | |
39c00dc2 | 643 | sensitive_data.keys[1] == NULL && |
644 | sensitive_data.keys[2] == NULL) { | |
645 | sensitive_data.keys[1] = key_load_public( | |
646 | _PATH_HOST_DSA_KEY_FILE, NULL); | |
647 | sensitive_data.keys[2] = key_load_public( | |
648 | _PATH_HOST_RSA_KEY_FILE, NULL); | |
649 | sensitive_data.external_keysign = 1; | |
650 | } | |
5260325f | 651 | } |
aa3378df | 652 | /* |
653 | * Get rid of any extra privileges that we may have. We will no | |
654 | * longer need them. Also, extra privileges could make it very hard | |
655 | * to read identity files and other non-world-readable files from the | |
656 | * user's home directory if it happens to be on a NFS volume where | |
657 | * root is mapped to nobody. | |
658 | */ | |
6213295d | 659 | if (original_effective_uid == 0) { |
660 | PRIV_START; | |
661 | permanently_set_uid(pw); | |
662 | } | |
5260325f | 663 | |
aa3378df | 664 | /* |
665 | * Now that we are back to our own permissions, create ~/.ssh | |
666 | * directory if it doesn\'t already exist. | |
667 | */ | |
c3abff07 | 668 | snprintf(buf, sizeof buf, "%.100s%s%.100s", pw->pw_dir, strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR); |
5260325f | 669 | if (stat(buf, &st) < 0) |
704b1659 | 670 | if (mkdir(buf, 0700) < 0) |
5260325f | 671 | error("Could not create directory '%.200s'.", buf); |
672 | ||
fee56204 | 673 | /* load options.identity_files */ |
674 | load_public_identity_files(); | |
675 | ||
676 | /* Expand ~ in known host file names. */ | |
677 | /* XXX mem-leaks: */ | |
fa08c86b | 678 | options.system_hostfile = |
679 | tilde_expand_filename(options.system_hostfile, original_real_uid); | |
680 | options.user_hostfile = | |
681 | tilde_expand_filename(options.user_hostfile, original_real_uid); | |
682 | options.system_hostfile2 = | |
683 | tilde_expand_filename(options.system_hostfile2, original_real_uid); | |
684 | options.user_hostfile2 = | |
685 | tilde_expand_filename(options.user_hostfile2, original_real_uid); | |
5260325f | 686 | |
67b75437 | 687 | signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */ |
688 | ||
5260325f | 689 | /* Log into the remote system. This never returns if the login fails. */ |
39c00dc2 | 690 | ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr, pw); |
8002af61 | 691 | |
692 | /* We no longer need the private host keys. Clear them now. */ | |
693 | if (sensitive_data.nkeys != 0) { | |
694 | for (i = 0; i < sensitive_data.nkeys; i++) { | |
695 | if (sensitive_data.keys[i] != NULL) { | |
696 | /* Destroys contents safely */ | |
697 | debug3("clear hostkey %d", i); | |
698 | key_free(sensitive_data.keys[i]); | |
699 | sensitive_data.keys[i] = NULL; | |
700 | } | |
701 | } | |
702 | xfree(sensitive_data.keys); | |
703 | } | |
05b7537a | 704 | for (i = 0; i < options.num_identity_files; i++) { |
705 | if (options.identity_files[i]) { | |
706 | xfree(options.identity_files[i]); | |
707 | options.identity_files[i] = NULL; | |
708 | } | |
709 | if (options.identity_keys[i]) { | |
710 | key_free(options.identity_keys[i]); | |
711 | options.identity_keys[i] = NULL; | |
712 | } | |
713 | } | |
5260325f | 714 | |
8ce64345 | 715 | exit_status = compat20 ? ssh_session2() : ssh_session(); |
716 | packet_close(); | |
6939bbd4 | 717 | |
5e96b616 | 718 | if (options.control_path != NULL && control_fd != -1) |
719 | unlink(options.control_path); | |
720 | ||
6939bbd4 | 721 | /* |
aff51935 | 722 | * Send SIGHUP to proxy command if used. We don't wait() in |
6939bbd4 | 723 | * case it hangs and instead rely on init to reap the child |
724 | */ | |
725 | if (proxy_command_pid > 1) | |
726 | kill(proxy_command_pid, SIGHUP); | |
727 | ||
8ce64345 | 728 | return exit_status; |
729 | } | |
730 | ||
d73a67d7 | 731 | #define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1" |
732 | ||
396c147e | 733 | static void |
b48eeb07 | 734 | x11_get_proto(char **_proto, char **_data) |
0b242b12 | 735 | { |
d73a67d7 | 736 | char cmd[1024]; |
0b242b12 | 737 | char line[512]; |
d73a67d7 | 738 | char xdisplay[512]; |
b48eeb07 | 739 | static char proto[512], data[512]; |
0b242b12 | 740 | FILE *f; |
d73a67d7 | 741 | int got_data = 0, generated = 0, do_unlink = 0, i; |
742 | char *display, *xauthdir, *xauthfile; | |
5d185586 | 743 | struct stat st; |
0b242b12 | 744 | |
d73a67d7 | 745 | xauthdir = xauthfile = NULL; |
b48eeb07 | 746 | *_proto = proto; |
747 | *_data = data; | |
748 | proto[0] = data[0] = '\0'; | |
d73a67d7 | 749 | |
5d185586 | 750 | if (!options.xauth_location || |
751 | (stat(options.xauth_location, &st) == -1)) { | |
752 | debug("No xauth program."); | |
753 | } else { | |
754 | if ((display = getenv("DISPLAY")) == NULL) { | |
755 | debug("x11_get_proto: DISPLAY not set"); | |
756 | return; | |
757 | } | |
d73a67d7 | 758 | /* |
759 | * Handle FamilyLocal case where $DISPLAY does | |
760 | * not match an authorization entry. For this we | |
761 | * just try "xauth list unix:displaynum.screennum". | |
762 | * XXX: "localhost" match to determine FamilyLocal | |
763 | * is not perfect. | |
764 | */ | |
765 | if (strncmp(display, "localhost:", 10) == 0) { | |
766 | snprintf(xdisplay, sizeof(xdisplay), "unix:%s", | |
767 | display + 10); | |
768 | display = xdisplay; | |
769 | } | |
770 | if (options.forward_x11_trusted == 0) { | |
771 | xauthdir = xmalloc(MAXPATHLEN); | |
772 | xauthfile = xmalloc(MAXPATHLEN); | |
773 | strlcpy(xauthdir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN); | |
774 | if (mkdtemp(xauthdir) != NULL) { | |
775 | do_unlink = 1; | |
776 | snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile", | |
777 | xauthdir); | |
778 | snprintf(cmd, sizeof(cmd), | |
779 | "%s -f %s generate %s " SSH_X11_PROTO | |
c876ee7e | 780 | " untrusted timeout 1200 2>" _PATH_DEVNULL, |
d73a67d7 | 781 | options.xauth_location, xauthfile, display); |
782 | debug2("x11_get_proto: %s", cmd); | |
783 | if (system(cmd) == 0) | |
784 | generated = 1; | |
785 | } | |
786 | } | |
787 | snprintf(cmd, sizeof(cmd), | |
788 | "%s %s%s list %s . 2>" _PATH_DEVNULL, | |
789 | options.xauth_location, | |
790 | generated ? "-f " : "" , | |
791 | generated ? xauthfile : "", | |
792 | display); | |
793 | debug2("x11_get_proto: %s", cmd); | |
794 | f = popen(cmd, "r"); | |
fa649821 | 795 | if (f && fgets(line, sizeof(line), f) && |
b48eeb07 | 796 | sscanf(line, "%*s %511s %511s", proto, data) == 2) |
fa649821 | 797 | got_data = 1; |
798 | if (f) | |
799 | pclose(f); | |
800 | } | |
d73a67d7 | 801 | |
802 | if (do_unlink) { | |
803 | unlink(xauthfile); | |
804 | rmdir(xauthdir); | |
805 | } | |
806 | if (xauthdir) | |
807 | xfree(xauthdir); | |
808 | if (xauthfile) | |
809 | xfree(xauthfile); | |
810 | ||
0b242b12 | 811 | /* |
812 | * If we didn't get authentication data, just make up some | |
813 | * data. The forwarding code will check the validity of the | |
814 | * response anyway, and substitute this data. The X11 | |
815 | * server, however, will ignore this fake data and use | |
816 | * whatever authentication mechanisms it was using otherwise | |
817 | * for the local connection. | |
818 | */ | |
819 | if (!got_data) { | |
ca75d7de | 820 | u_int32_t rnd = 0; |
0b242b12 | 821 | |
d73a67d7 | 822 | logit("Warning: No xauth data; " |
823 | "using fake authentication data for X11 forwarding."); | |
824 | strlcpy(proto, SSH_X11_PROTO, sizeof proto); | |
0b242b12 | 825 | for (i = 0; i < 16; i++) { |
826 | if (i % 4 == 0) | |
ca75d7de | 827 | rnd = arc4random(); |
d73a67d7 | 828 | snprintf(data + 2 * i, sizeof data - 2 * i, "%02x", |
ca75d7de | 829 | rnd & 0xff); |
830 | rnd >>= 8; | |
0b242b12 | 831 | } |
832 | } | |
833 | } | |
834 | ||
396c147e | 835 | static void |
fa08c86b | 836 | ssh_init_forwarding(void) |
837 | { | |
02a024dd | 838 | int success = 0; |
fa08c86b | 839 | int i; |
02a024dd | 840 | |
fa08c86b | 841 | /* Initiate local TCP/IP port forwardings. */ |
842 | for (i = 0; i < options.num_local_forwards; i++) { | |
843 | debug("Connections to local port %d forwarded to remote address %.200s:%d", | |
844 | options.local_forwards[i].port, | |
845 | options.local_forwards[i].host, | |
846 | options.local_forwards[i].host_port); | |
5641aefa | 847 | success += channel_setup_local_fwd_listener( |
fa08c86b | 848 | options.local_forwards[i].port, |
849 | options.local_forwards[i].host, | |
850 | options.local_forwards[i].host_port, | |
851 | options.gateway_ports); | |
852 | } | |
02a024dd | 853 | if (i > 0 && success == 0) |
854 | error("Could not request local forwarding."); | |
fa08c86b | 855 | |
856 | /* Initiate remote TCP/IP port forwardings. */ | |
857 | for (i = 0; i < options.num_remote_forwards; i++) { | |
858 | debug("Connections to remote port %d forwarded to local address %.200s:%d", | |
859 | options.remote_forwards[i].port, | |
860 | options.remote_forwards[i].host, | |
861 | options.remote_forwards[i].host_port); | |
862 | channel_request_remote_forwarding( | |
863 | options.remote_forwards[i].port, | |
864 | options.remote_forwards[i].host, | |
865 | options.remote_forwards[i].host_port); | |
866 | } | |
867 | } | |
868 | ||
396c147e | 869 | static void |
fa08c86b | 870 | check_agent_present(void) |
871 | { | |
872 | if (options.forward_agent) { | |
873 | /* Clear agent forwarding if we don\'t have an agent. */ | |
8b10e20e | 874 | if (!ssh_agent_present()) |
fa08c86b | 875 | options.forward_agent = 0; |
fa08c86b | 876 | } |
877 | } | |
878 | ||
396c147e | 879 | static int |
8ce64345 | 880 | ssh_session(void) |
881 | { | |
882 | int type; | |
8ce64345 | 883 | int interactive = 0; |
884 | int have_tty = 0; | |
885 | struct winsize ws; | |
8ce64345 | 886 | char *cp; |
887 | ||
5260325f | 888 | /* Enable compression if requested. */ |
889 | if (options.compression) { | |
890 | debug("Requesting compression at level %d.", options.compression_level); | |
891 | ||
892 | if (options.compression_level < 1 || options.compression_level > 9) | |
893 | fatal("Compression level must be from 1 (fast) to 9 (slow, best)."); | |
894 | ||
895 | /* Send the request. */ | |
896 | packet_start(SSH_CMSG_REQUEST_COMPRESSION); | |
897 | packet_put_int(options.compression_level); | |
898 | packet_send(); | |
899 | packet_write_wait(); | |
54a5250f | 900 | type = packet_read(); |
5260325f | 901 | if (type == SSH_SMSG_SUCCESS) |
902 | packet_start_compression(options.compression_level); | |
903 | else if (type == SSH_SMSG_FAILURE) | |
bbe88b6d | 904 | logit("Warning: Remote host refused compression."); |
5260325f | 905 | else |
906 | packet_disconnect("Protocol error waiting for compression response."); | |
907 | } | |
908 | /* Allocate a pseudo tty if appropriate. */ | |
909 | if (tty_flag) { | |
910 | debug("Requesting pty."); | |
911 | ||
912 | /* Start the packet. */ | |
913 | packet_start(SSH_CMSG_REQUEST_PTY); | |
914 | ||
915 | /* Store TERM in the packet. There is no limit on the | |
916 | length of the string. */ | |
917 | cp = getenv("TERM"); | |
918 | if (!cp) | |
919 | cp = ""; | |
449c5ba5 | 920 | packet_put_cstring(cp); |
5260325f | 921 | |
922 | /* Store window size in the packet. */ | |
923 | if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0) | |
924 | memset(&ws, 0, sizeof(ws)); | |
925 | packet_put_int(ws.ws_row); | |
926 | packet_put_int(ws.ws_col); | |
927 | packet_put_int(ws.ws_xpixel); | |
928 | packet_put_int(ws.ws_ypixel); | |
929 | ||
930 | /* Store tty modes in the packet. */ | |
30dcc918 | 931 | tty_make_modes(fileno(stdin), NULL); |
5260325f | 932 | |
933 | /* Send the packet, and wait for it to leave. */ | |
934 | packet_send(); | |
935 | packet_write_wait(); | |
936 | ||
937 | /* Read response from the server. */ | |
54a5250f | 938 | type = packet_read(); |
4fe2af09 | 939 | if (type == SSH_SMSG_SUCCESS) { |
5260325f | 940 | interactive = 1; |
8ce64345 | 941 | have_tty = 1; |
4fe2af09 | 942 | } else if (type == SSH_SMSG_FAILURE) |
bbe88b6d | 943 | logit("Warning: Remote host failed or refused to allocate a pseudo tty."); |
5260325f | 944 | else |
945 | packet_disconnect("Protocol error waiting for pty request response."); | |
946 | } | |
947 | /* Request X11 forwarding if enabled and DISPLAY is set. */ | |
948 | if (options.forward_x11 && getenv("DISPLAY") != NULL) { | |
b48eeb07 | 949 | char *proto, *data; |
0b242b12 | 950 | /* Get reasonable local authentication information. */ |
b48eeb07 | 951 | x11_get_proto(&proto, &data); |
0b242b12 | 952 | /* Request forwarding with authentication spoofing. */ |
5260325f | 953 | debug("Requesting X11 forwarding with authentication spoofing."); |
0b242b12 | 954 | x11_request_forwarding_with_spoofing(0, proto, data); |
5260325f | 955 | |
956 | /* Read response from the server. */ | |
54a5250f | 957 | type = packet_read(); |
5260325f | 958 | if (type == SSH_SMSG_SUCCESS) { |
5260325f | 959 | interactive = 1; |
0b242b12 | 960 | } else if (type == SSH_SMSG_FAILURE) { |
bbe88b6d | 961 | logit("Warning: Remote host denied X11 forwarding."); |
0b242b12 | 962 | } else { |
5260325f | 963 | packet_disconnect("Protocol error waiting for X11 forwarding"); |
0b242b12 | 964 | } |
5260325f | 965 | } |
966 | /* Tell the packet module whether this is an interactive session. */ | |
b5c334cc | 967 | packet_set_interactive(interactive); |
5260325f | 968 | |
969 | /* Request authentication agent forwarding if appropriate. */ | |
fa08c86b | 970 | check_agent_present(); |
971 | ||
5260325f | 972 | if (options.forward_agent) { |
973 | debug("Requesting authentication agent forwarding."); | |
974 | auth_request_forwarding(); | |
975 | ||
976 | /* Read response from the server. */ | |
54a5250f | 977 | type = packet_read(); |
95500969 | 978 | packet_check_eom(); |
5260325f | 979 | if (type != SSH_SMSG_SUCCESS) |
bbe88b6d | 980 | logit("Warning: Remote host denied authentication agent forwarding."); |
5260325f | 981 | } |
8efc0c15 | 982 | |
fa08c86b | 983 | /* Initiate port forwardings. */ |
984 | ssh_init_forwarding(); | |
5260325f | 985 | |
aa3378df | 986 | /* If requested, let ssh continue in the background. */ |
6ae2364d | 987 | if (fork_after_authentication_flag) |
aa3378df | 988 | if (daemon(1, 1) < 0) |
989 | fatal("daemon() failed: %.200s", strerror(errno)); | |
990 | ||
991 | /* | |
992 | * If a command was specified on the command line, execute the | |
993 | * command now. Otherwise request the server to start a shell. | |
994 | */ | |
5260325f | 995 | if (buffer_len(&command) > 0) { |
996 | int len = buffer_len(&command); | |
997 | if (len > 900) | |
998 | len = 900; | |
6c0fa2b1 | 999 | debug("Sending command: %.*s", len, (u_char *)buffer_ptr(&command)); |
5260325f | 1000 | packet_start(SSH_CMSG_EXEC_CMD); |
1001 | packet_put_string(buffer_ptr(&command), buffer_len(&command)); | |
1002 | packet_send(); | |
1003 | packet_write_wait(); | |
1004 | } else { | |
1005 | debug("Requesting shell."); | |
1006 | packet_start(SSH_CMSG_EXEC_SHELL); | |
1007 | packet_send(); | |
1008 | packet_write_wait(); | |
1009 | } | |
1010 | ||
1011 | /* Enter the interactive session. */ | |
4bf9c10e | 1012 | return client_loop(have_tty, tty_flag ? |
1013 | options.escape_char : SSH_ESCAPECHAR_NONE, 0); | |
8ce64345 | 1014 | } |
5260325f | 1015 | |
396c147e | 1016 | static void |
5e96b616 | 1017 | ssh_subsystem_reply(int type, u_int32_t seq, void *ctxt) |
1f3bf5aa | 1018 | { |
1019 | int id, len; | |
1020 | ||
1021 | id = packet_get_int(); | |
1022 | len = buffer_len(&command); | |
ce91d6f8 | 1023 | if (len > 900) |
1024 | len = 900; | |
95500969 | 1025 | packet_check_eom(); |
1f3bf5aa | 1026 | if (type == SSH2_MSG_CHANNEL_FAILURE) |
1027 | fatal("Request for subsystem '%.*s' failed on channel %d", | |
6c0fa2b1 | 1028 | len, (u_char *)buffer_ptr(&command), id); |
1f3bf5aa | 1029 | } |
1030 | ||
e0ae8728 | 1031 | void |
5d8d32a3 | 1032 | client_global_request_reply_fwd(int type, u_int32_t seq, void *ctxt) |
e0ae8728 | 1033 | { |
1034 | int i; | |
1035 | ||
1036 | i = client_global_request_id++; | |
5d8d32a3 | 1037 | if (i >= options.num_remote_forwards) |
e0ae8728 | 1038 | return; |
e0ae8728 | 1039 | debug("remote forward %s for: listen %d, connect %s:%d", |
1040 | type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure", | |
1041 | options.remote_forwards[i].port, | |
1042 | options.remote_forwards[i].host, | |
1043 | options.remote_forwards[i].host_port); | |
1044 | if (type == SSH2_MSG_REQUEST_FAILURE) | |
bbe88b6d | 1045 | logit("Warning: remote port forwarding failed for listen port %d", |
e0ae8728 | 1046 | options.remote_forwards[i].port); |
1047 | } | |
1048 | ||
396c147e | 1049 | static void |
5e96b616 | 1050 | ssh_control_listener(void) |
8ce64345 | 1051 | { |
5e96b616 | 1052 | struct sockaddr_un addr; |
1053 | mode_t old_umask; | |
4b5df124 | 1054 | int addr_len; |
1055 | ||
0d34d6ce | 1056 | if (options.control_path == NULL || options.control_master <= 0) |
5e96b616 | 1057 | return; |
b5c334cc | 1058 | |
5e96b616 | 1059 | memset(&addr, '\0', sizeof(addr)); |
1060 | addr.sun_family = AF_UNIX; | |
4b5df124 | 1061 | addr_len = offsetof(struct sockaddr_un, sun_path) + |
5e96b616 | 1062 | strlen(options.control_path) + 1; |
8ce64345 | 1063 | |
5e96b616 | 1064 | if (strlcpy(addr.sun_path, options.control_path, |
1065 | sizeof(addr.sun_path)) >= sizeof(addr.sun_path)) | |
1066 | fatal("ControlPath too long"); | |
8ce64345 | 1067 | |
5e96b616 | 1068 | if ((control_fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) |
1069 | fatal("%s socket(): %s\n", __func__, strerror(errno)); | |
1070 | ||
1071 | old_umask = umask(0177); | |
4b5df124 | 1072 | if (bind(control_fd, (struct sockaddr*)&addr, addr_len) == -1) { |
5e96b616 | 1073 | control_fd = -1; |
1074 | if (errno == EINVAL) | |
1075 | fatal("ControlSocket %s already exists", | |
1076 | options.control_path); | |
1077 | else | |
1078 | fatal("%s bind(): %s\n", __func__, strerror(errno)); | |
8ce64345 | 1079 | } |
5e96b616 | 1080 | umask(old_umask); |
1081 | ||
1082 | if (listen(control_fd, 64) == -1) | |
1083 | fatal("%s listen(): %s\n", __func__, strerror(errno)); | |
1084 | ||
1085 | set_nonblock(control_fd); | |
1086 | } | |
1087 | ||
1088 | /* request pty/x11/agent/tcpfwd/shell for channel */ | |
1089 | static void | |
1090 | ssh_session2_setup(int id, void *arg) | |
1091 | { | |
1786be35 | 1092 | extern char **environ; |
1093 | ||
5e96b616 | 1094 | int interactive = tty_flag; |
1095 | if (options.forward_x11 && getenv("DISPLAY") != NULL) { | |
b48eeb07 | 1096 | char *proto, *data; |
0b242b12 | 1097 | /* Get reasonable local authentication information. */ |
b48eeb07 | 1098 | x11_get_proto(&proto, &data); |
0b242b12 | 1099 | /* Request forwarding with authentication spoofing. */ |
1100 | debug("Requesting X11 forwarding with authentication spoofing."); | |
1101 | x11_request_forwarding_with_spoofing(id, proto, data); | |
b5c334cc | 1102 | interactive = 1; |
0b242b12 | 1103 | /* XXX wait for reply */ |
1104 | } | |
1105 | ||
fa08c86b | 1106 | check_agent_present(); |
1107 | if (options.forward_agent) { | |
1108 | debug("Requesting authentication agent forwarding."); | |
1109 | channel_request_start(id, "auth-agent-req@openssh.com", 0); | |
1110 | packet_send(); | |
1111 | } | |
1112 | ||
5e96b616 | 1113 | client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"), |
1786be35 | 1114 | NULL, fileno(stdin), &command, environ, &ssh_subsystem_reply); |
1f3bf5aa | 1115 | |
b5c334cc | 1116 | packet_set_interactive(interactive); |
8ce64345 | 1117 | } |
1118 | ||
bcdb96c2 | 1119 | /* open new channel for a session */ |
396c147e | 1120 | static int |
bcdb96c2 | 1121 | ssh_session2_open(void) |
8ce64345 | 1122 | { |
719fc62f | 1123 | Channel *c; |
1124 | int window, packetmax, in, out, err; | |
2e73a022 | 1125 | |
14a9a859 | 1126 | if (stdin_null_flag) { |
5ca51e19 | 1127 | in = open(_PATH_DEVNULL, O_RDONLY); |
14a9a859 | 1128 | } else { |
1129 | in = dup(STDIN_FILENO); | |
1130 | } | |
2e73a022 | 1131 | out = dup(STDOUT_FILENO); |
1132 | err = dup(STDERR_FILENO); | |
8ce64345 | 1133 | |
1134 | if (in < 0 || out < 0 || err < 0) | |
14a9a859 | 1135 | fatal("dup() in/out/err failed"); |
8ce64345 | 1136 | |
a22aff1f | 1137 | /* enable nonblocking unless tty */ |
1138 | if (!isatty(in)) | |
1139 | set_nonblock(in); | |
1140 | if (!isatty(out)) | |
1141 | set_nonblock(out); | |
1142 | if (!isatty(err)) | |
1143 | set_nonblock(err); | |
1144 | ||
bcbf86ec | 1145 | window = CHAN_SES_WINDOW_DEFAULT; |
1146 | packetmax = CHAN_SES_PACKET_DEFAULT; | |
ea9700ba | 1147 | if (tty_flag) { |
1148 | window >>= 1; | |
1149 | packetmax >>= 1; | |
8ce64345 | 1150 | } |
719fc62f | 1151 | c = channel_new( |
8ce64345 | 1152 | "session", SSH_CHANNEL_OPENING, in, out, err, |
bcbf86ec | 1153 | window, packetmax, CHAN_EXTENDED_WRITE, |
0d942eff | 1154 | "client-session", /*nonblock*/0); |
8ce64345 | 1155 | |
bcdb96c2 | 1156 | debug3("ssh_session2_open: channel_new: %d", c->self); |
eb0dd41f | 1157 | |
36e1f6a1 | 1158 | channel_send_open(c->self); |
bcdb96c2 | 1159 | if (!no_shell_flag) |
5e96b616 | 1160 | channel_register_confirm(c->self, ssh_session2_setup, NULL); |
5260325f | 1161 | |
719fc62f | 1162 | return c->self; |
eb0dd41f | 1163 | } |
1164 | ||
396c147e | 1165 | static int |
eb0dd41f | 1166 | ssh_session2(void) |
1167 | { | |
bcdb96c2 | 1168 | int id = -1; |
eb0dd41f | 1169 | |
1170 | /* XXX should be pre-session */ | |
1171 | ssh_init_forwarding(); | |
5e96b616 | 1172 | ssh_control_listener(); |
eb0dd41f | 1173 | |
bcdb96c2 | 1174 | if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN)) |
1175 | id = ssh_session2_open(); | |
eb0dd41f | 1176 | |
1177 | /* If requested, let ssh continue in the background. */ | |
1178 | if (fork_after_authentication_flag) | |
1179 | if (daemon(1, 1) < 0) | |
1180 | fatal("daemon() failed: %.200s", strerror(errno)); | |
1181 | ||
4bf9c10e | 1182 | return client_loop(tty_flag, tty_flag ? |
1183 | options.escape_char : SSH_ESCAPECHAR_NONE, id); | |
8efc0c15 | 1184 | } |
fa08c86b | 1185 | |
396c147e | 1186 | static void |
fee56204 | 1187 | load_public_identity_files(void) |
1188 | { | |
1189 | char *filename; | |
2e23cde0 | 1190 | int i = 0; |
0659cace | 1191 | Key *public; |
383546c4 | 1192 | #ifdef SMARTCARD |
0659cace | 1193 | Key **keys; |
1194 | ||
9ff6f66f | 1195 | if (options.smartcard_device != NULL && |
0659cace | 1196 | options.num_identity_files < SSH_MAX_IDENTITY_FILES && |
1197 | (keys = sc_get_keys(options.smartcard_device, NULL)) != NULL ) { | |
1198 | int count = 0; | |
1199 | for (i = 0; keys[i] != NULL; i++) { | |
1200 | count++; | |
0659cace | 1201 | memmove(&options.identity_files[1], &options.identity_files[0], |
1202 | sizeof(char *) * (SSH_MAX_IDENTITY_FILES - 1)); | |
1203 | memmove(&options.identity_keys[1], &options.identity_keys[0], | |
1204 | sizeof(Key *) * (SSH_MAX_IDENTITY_FILES - 1)); | |
1205 | options.num_identity_files++; | |
1206 | options.identity_keys[0] = keys[i]; | |
244e796f | 1207 | options.identity_files[0] = sc_get_key_label(keys[i]); |
0659cace | 1208 | } |
1c2deed1 | 1209 | if (options.num_identity_files > SSH_MAX_IDENTITY_FILES) |
1210 | options.num_identity_files = SSH_MAX_IDENTITY_FILES; | |
0659cace | 1211 | i = count; |
1212 | xfree(keys); | |
383546c4 | 1213 | } |
3e984472 | 1214 | #endif /* SMARTCARD */ |
2e23cde0 | 1215 | for (; i < options.num_identity_files; i++) { |
1216 | filename = tilde_expand_filename(options.identity_files[i], | |
1217 | original_real_uid); | |
1218 | public = key_load_public(filename, NULL); | |
1219 | debug("identity file %s type %d", filename, | |
1220 | public ? public->type : -1); | |
1221 | xfree(options.identity_files[i]); | |
1222 | options.identity_files[i] = filename; | |
1223 | options.identity_keys[i] = public; | |
1224 | } | |
fee56204 | 1225 | } |
5e96b616 | 1226 | |
1227 | static void | |
1228 | control_client_sighandler(int signo) | |
1229 | { | |
1230 | control_client_terminate = signo; | |
1231 | } | |
1232 | ||
1233 | static void | |
1234 | control_client_sigrelay(int signo) | |
1235 | { | |
1236 | if (control_server_pid > 1) | |
1237 | kill(control_server_pid, signo); | |
1238 | } | |
1239 | ||
67a08279 | 1240 | static int |
1241 | env_permitted(char *env) | |
1242 | { | |
1243 | int i; | |
1244 | char name[1024], *cp; | |
1245 | ||
1246 | strlcpy(name, env, sizeof(name)); | |
1247 | if ((cp = strchr(name, '=')) == NULL) | |
1248 | return (0); | |
1249 | ||
1250 | *cp = '\0'; | |
1251 | ||
1252 | for (i = 0; i < options.num_send_env; i++) | |
1253 | if (match_pattern(name, options.send_env[i])) | |
1254 | return (1); | |
1255 | ||
1256 | return (0); | |
1257 | } | |
1258 | ||
5e96b616 | 1259 | static void |
1260 | control_client(const char *path) | |
1261 | { | |
1262 | struct sockaddr_un addr; | |
a7e124fe | 1263 | int i, r, fd, sock, exitval, num_env, addr_len; |
5e96b616 | 1264 | Buffer m; |
f8c6db83 | 1265 | char *term; |
1786be35 | 1266 | extern char **environ; |
f8c6db83 | 1267 | u_int flags; |
f2107e97 | 1268 | |
a7e124fe | 1269 | if (stdin_null_flag) { |
1270 | if ((fd = open(_PATH_DEVNULL, O_RDONLY)) == -1) | |
1271 | fatal("open(/dev/null): %s", strerror(errno)); | |
1272 | if (dup2(fd, STDIN_FILENO) == -1) | |
1273 | fatal("dup2: %s", strerror(errno)); | |
1274 | if (fd > STDERR_FILENO) | |
1275 | close(fd); | |
1276 | } | |
1277 | ||
5e96b616 | 1278 | memset(&addr, '\0', sizeof(addr)); |
1279 | addr.sun_family = AF_UNIX; | |
4b5df124 | 1280 | addr_len = offsetof(struct sockaddr_un, sun_path) + |
5e96b616 | 1281 | strlen(path) + 1; |
1282 | ||
1283 | if (strlcpy(addr.sun_path, path, | |
1284 | sizeof(addr.sun_path)) >= sizeof(addr.sun_path)) | |
1285 | fatal("ControlPath too long"); | |
1286 | ||
1287 | if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) | |
1288 | fatal("%s socket(): %s", __func__, strerror(errno)); | |
1289 | ||
4b5df124 | 1290 | if (connect(sock, (struct sockaddr*)&addr, addr_len) == -1) |
5e96b616 | 1291 | fatal("Couldn't connect to %s: %s", path, strerror(errno)); |
1292 | ||
f8c6db83 | 1293 | if ((term = getenv("TERM")) == NULL) |
1294 | term = ""; | |
1295 | ||
1296 | flags = 0; | |
1297 | if (tty_flag) | |
1298 | flags |= SSHMUX_FLAG_TTY; | |
1299 | if (subsystem_flag) | |
1300 | flags |= SSHMUX_FLAG_SUBSYS; | |
5e96b616 | 1301 | |
5e96b616 | 1302 | buffer_init(&m); |
1303 | ||
f8c6db83 | 1304 | /* Send our command to server */ |
1305 | buffer_put_int(&m, mux_command); | |
1306 | buffer_put_int(&m, flags); | |
1307 | if (ssh_msg_send(sock, /* version */1, &m) == -1) | |
1308 | fatal("%s: msg_send", __func__); | |
1309 | buffer_clear(&m); | |
1310 | ||
1311 | /* Get authorisation status and PID of controlee */ | |
5e96b616 | 1312 | if (ssh_msg_recv(sock, &m) == -1) |
1313 | fatal("%s: msg_recv", __func__); | |
f8c6db83 | 1314 | if (buffer_get_char(&m) != 1) |
5e96b616 | 1315 | fatal("%s: wrong version", __func__); |
0d34d6ce | 1316 | if (buffer_get_int(&m) != 1) |
1317 | fatal("Connection to master denied"); | |
5e96b616 | 1318 | control_server_pid = buffer_get_int(&m); |
1319 | ||
5e96b616 | 1320 | buffer_clear(&m); |
5e96b616 | 1321 | |
f8c6db83 | 1322 | switch (mux_command) { |
1323 | case SSHMUX_COMMAND_ALIVE_CHECK: | |
1324 | fprintf(stderr, "Master running (pid=%d)\r\n", | |
1325 | control_server_pid); | |
1326 | exit(0); | |
1327 | case SSHMUX_COMMAND_TERMINATE: | |
1328 | fprintf(stderr, "Exit request sent.\r\n"); | |
1329 | exit(0); | |
1330 | case SSHMUX_COMMAND_OPEN: | |
1331 | /* continue below */ | |
1332 | break; | |
1333 | default: | |
1334 | fatal("silly mux_command %d", mux_command); | |
1335 | } | |
1336 | ||
1337 | /* SSHMUX_COMMAND_OPEN */ | |
1338 | buffer_put_cstring(&m, term); | |
5e96b616 | 1339 | buffer_append(&command, "\0", 1); |
1340 | buffer_put_cstring(&m, buffer_ptr(&command)); | |
1341 | ||
67a08279 | 1342 | if (options.num_send_env == 0 || environ == NULL) { |
1343 | buffer_put_int(&m, 0); | |
f2107e97 | 1344 | } else { |
67a08279 | 1345 | /* Pass environment */ |
1346 | num_env = 0; | |
1347 | for (i = 0; environ[i] != NULL; i++) | |
1348 | if (env_permitted(environ[i])) | |
1349 | num_env++; /* Count */ | |
f2107e97 | 1350 | |
67a08279 | 1351 | buffer_put_int(&m, num_env); |
1352 | ||
77c50919 | 1353 | for (i = 0; environ[i] != NULL && num_env >= 0; i++) |
1354 | if (env_permitted(environ[i])) { | |
1355 | num_env--; | |
67a08279 | 1356 | buffer_put_cstring(&m, environ[i]); |
77c50919 | 1357 | } |
67a08279 | 1358 | } |
1786be35 | 1359 | |
f8c6db83 | 1360 | if (ssh_msg_send(sock, /* version */1, &m) == -1) |
5e96b616 | 1361 | fatal("%s: msg_send", __func__); |
1362 | ||
1363 | mm_send_fd(sock, STDIN_FILENO); | |
1364 | mm_send_fd(sock, STDOUT_FILENO); | |
1365 | mm_send_fd(sock, STDERR_FILENO); | |
1366 | ||
1367 | /* Wait for reply, so master has a chance to gather ttymodes */ | |
1368 | buffer_clear(&m); | |
1369 | if (ssh_msg_recv(sock, &m) == -1) | |
1370 | fatal("%s: msg_recv", __func__); | |
f8c6db83 | 1371 | if (buffer_get_char(&m) != 1) |
1372 | fatal("%s: wrong version", __func__); | |
5e96b616 | 1373 | buffer_free(&m); |
1374 | ||
d3e5d1e9 | 1375 | signal(SIGHUP, control_client_sighandler); |
78d2b454 | 1376 | signal(SIGINT, control_client_sighandler); |
1377 | signal(SIGTERM, control_client_sighandler); | |
1378 | signal(SIGWINCH, control_client_sigrelay); | |
1379 | ||
5e96b616 | 1380 | if (tty_flag) |
1381 | enter_raw_mode(); | |
1382 | ||
1383 | /* Stick around until the controlee closes the client_fd */ | |
1384 | exitval = 0; | |
1385 | for (;!control_client_terminate;) { | |
1386 | r = read(sock, &exitval, sizeof(exitval)); | |
1387 | if (r == 0) { | |
1388 | debug2("Received EOF from master"); | |
1389 | break; | |
1390 | } | |
1391 | if (r > 0) | |
1392 | debug2("Received exit status from master %d", exitval); | |
1393 | if (r == -1 && errno != EINTR) | |
1394 | fatal("%s: read %s", __func__, strerror(errno)); | |
1395 | } | |
1396 | ||
1397 | if (control_client_terminate) | |
1398 | debug2("Exiting on signal %d", control_client_terminate); | |
1399 | ||
1400 | close(sock); | |
1401 | ||
1402 | leave_raw_mode(); | |
1403 | ||
1404 | if (tty_flag && options.log_level != SYSLOG_LEVEL_QUIET) | |
1405 | fprintf(stderr, "Connection to master closed.\r\n"); | |
1406 | ||
1407 | exit(exitval); | |
1408 | } |