1 /* $OpenBSD: ssh.c,v 1.420 2015/07/30 00:01:34 djm Exp $ */
2 /*
3 * Author: Tatu Ylonen <ylo@cs.hut.fi>
4 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5 * All rights reserved
6 * Ssh client program. This program can be used to log into a remote machine.
7 * The software supports strong authentication, encryption, and forwarding
8 * of X11, TCP/IP, and authentication connections.
9 *
10 * As far as I am concerned, the code I have written for this software
11 * can be used freely for any purpose. Any derived versions of this
12 * software must be clearly marked as such, and if the derived work is
13 * incompatible with the protocol description in the RFC file, it must be
14 * called by a name other than "ssh" or "Secure Shell".
15 *
16 * Copyright (c) 1999 Niels Provos. All rights reserved.
17 * Copyright (c) 2000, 2001, 2002, 2003 Markus Friedl. All rights reserved.
18 *
19 * Modified to work with SSL by Niels Provos <provos@citi.umich.edu>
20 * in Canada (German citizen).
21 *
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
24 * are met:
25 * 1. Redistributions of source code must retain the above copyright
26 * notice, this list of conditions and the following disclaimer.
27 * 2. Redistributions in binary form must reproduce the above copyright
28 * notice, this list of conditions and the following disclaimer in the
29 * documentation and/or other materials provided with the distribution.
30 *
31 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
32 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
33 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
34 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
35 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
36 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
37 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
38 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
39 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
40 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
41 */
42
43 #include "includes.h"
44
45 #include <sys/types.h>
46 #ifdef HAVE_SYS_STAT_H
47 # include <sys/stat.h>
48 #endif
49 #include <sys/resource.h>
50 #include <sys/ioctl.h>
51 #include <sys/socket.h>
52 #include <sys/wait.h>
53
54 #include <ctype.h>
55 #include <errno.h>
56 #include <fcntl.h>
57 #include <netdb.h>
58 #ifdef HAVE_PATHS_H
59 #include <paths.h>
60 #endif
61 #include <pwd.h>
62 #include <signal.h>
63 #include <stdarg.h>
64 #include <stddef.h>
65 #include <stdio.h>
66 #include <stdlib.h>
67 #include <string.h>
68 #include <unistd.h>
69 #include <limits.h>
70
71 #include <netinet/in.h>
72 #include <arpa/inet.h>
73
74 #ifdef WITH_OPENSSL
75 #include <openssl/evp.h>
76 #include <openssl/err.h>
77 #endif
78 #include "openbsd-compat/openssl-compat.h"
79 #include "openbsd-compat/sys-queue.h"
80
81 #include "xmalloc.h"
82 #include "ssh.h"
83 #include "ssh1.h"
84 #include "ssh2.h"
85 #include "canohost.h"
86 #include "compat.h"
87 #include "cipher.h"
88 #include "digest.h"
89 #include "packet.h"
90 #include "buffer.h"
91 #include "channels.h"
92 #include "key.h"
93 #include "authfd.h"
94 #include "authfile.h"
95 #include "pathnames.h"
96 #include "dispatch.h"
97 #include "clientloop.h"
98 #include "log.h"
99 #include "misc.h"
100 #include "readconf.h"
101 #include "sshconnect.h"
102 #include "kex.h"
103 #include "mac.h"
104 #include "sshpty.h"
105 #include "match.h"
106 #include "msg.h"
107 #include "uidswap.h"
108 #include "roaming.h"
109 #include "version.h"
110 #include "ssherr.h"
111 #include "myproposal.h"
112
113 #ifdef ENABLE_PKCS11
114 #include "ssh-pkcs11.h"
115 #endif
116
117 extern char *__progname;
118
119 /* Saves a copy of argv for setproctitle emulation */
120 #ifndef HAVE_SETPROCTITLE
121 static char **saved_av;
122 #endif
123
124 /* Flag indicating whether debug mode is on. May be set on the command line. */
125 int debug_flag = 0;
126
127 /* Flag indicating whether a tty should be requested */
128 int tty_flag = 0;
129
130 /* don't exec a shell */
131 int no_shell_flag = 0;
132
133 /*
134 * Flag indicating that nothing should be read from stdin. This can be set
135 * on the command line.
136 */
137 int stdin_null_flag = 0;
138
139 /*
140 * Flag indicating that the current process should be backgrounded and
141 * a new slave launched in the foreground for ControlPersist.
142 */
143 int need_controlpersist_detach = 0;
144
145 /* Copies of flags for ControlPersist foreground slave */
146 int ostdin_null_flag, ono_shell_flag, otty_flag, orequest_tty;
147
148 /*
149 * Flag indicating that ssh should fork after authentication. This is useful
150 * so that the passphrase can be entered manually, and then ssh goes to the
151 * background.
152 */
153 int fork_after_authentication_flag = 0;
154
155 /* forward stdio to remote host and port */
156 char *stdio_forward_host = NULL;
157 int stdio_forward_port = 0;
158
159 /*
160 * General data structure for command line options and options configurable
161 * in configuration files. See readconf.h.
162 */
163 Options options;
164
165 /* optional user configfile */
166 char *config = NULL;
167
168 /*
169 * Name of the host we are connecting to. This is the name given on the
170 * command line, or the HostName specified for the user-supplied name in a
171 * configuration file.
172 */
173 char *host;
174
175 /* socket address the host resolves to */
176 struct sockaddr_storage hostaddr;
177
178 /* Private host keys. */
179 Sensitive sensitive_data;
180
181 /* Original real UID. */
182 uid_t original_real_uid;
183 uid_t original_effective_uid;
184
185 /* command to be executed */
186 Buffer command;
187
188 /* Should we execute a command or invoke a subsystem? */
189 int subsystem_flag = 0;
190
191 /* # of replies received for global requests */
192 static int remote_forward_confirms_received = 0;
193
194 /* mux.c */
195 extern int muxserver_sock;
196 extern u_int muxclient_command;
197
198 /* Prints a help message to the user. This function never returns. */
199
200 static void
usage(void)201 usage(void)
202 {
203 fprintf(stderr,
204 "usage: ssh [-1246AaCfGgKkMNnqsTtVvXxYy] [-b bind_address] [-c cipher_spec]\n"
205 " [-D [bind_address:]port] [-E log_file] [-e escape_char]\n"
206 " [-F configfile] [-I pkcs11] [-i identity_file]\n"
207 " [-L address] [-l login_name] [-m mac_spec]\n"
208 " [-O ctl_cmd] [-o option] [-p port]\n"
209 " [-Q cipher | cipher-auth | mac | kex | key]\n"
210 " [-R address] [-S ctl_path] [-W host:port]\n"
211 " [-w local_tun[:remote_tun]] [user@]hostname [command]\n"
212 );
213 exit(255);
214 }
215
216 static int ssh_session(void);
217 static int ssh_session2(void);
218 static void load_public_identity_files(void);
219 static void main_sigchld_handler(int);
220
221 /* from muxclient.c */
222 void muxclient(const char *);
223 void muxserver_listen(void);
224
225 /* ~/ expand a list of paths. NB. assumes path[n] is heap-allocated. */
226 static void
tilde_expand_paths(char ** paths,u_int num_paths)227 tilde_expand_paths(char **paths, u_int num_paths)
228 {
229 u_int i;
230 char *cp;
231
232 for (i = 0; i < num_paths; i++) {
233 cp = tilde_expand_filename(paths[i], original_real_uid);
234 free(paths[i]);
235 paths[i] = cp;
236 }
237 }
238
239 /*
240 * Attempt to resolve a host name / port to a set of addresses and
241 * optionally return any CNAMEs encountered along the way.
242 * Returns NULL on failure.
243 * NB. this function must operate with a options having undefined members.
244 */
245 static struct addrinfo *
resolve_host(const char * name,int port,int logerr,char * cname,size_t clen)246 resolve_host(const char *name, int port, int logerr, char *cname, size_t clen)
247 {
248 char strport[NI_MAXSERV];
249 struct addrinfo hints, *res;
250 int gaierr, loglevel = SYSLOG_LEVEL_DEBUG1;
251
252 if (port <= 0)
253 port = default_ssh_port();
254
255 snprintf(strport, sizeof strport, "%u", port);
256 memset(&hints, 0, sizeof(hints));
257 hints.ai_family = options.address_family == -1 ?
258 AF_UNSPEC : options.address_family;
259 hints.ai_socktype = SOCK_STREAM;
260 if (cname != NULL)
261 hints.ai_flags = AI_CANONNAME;
262 if ((gaierr = getaddrinfo(name, strport, &hints, &res)) != 0) {
263 if (logerr || (gaierr != EAI_NONAME && gaierr != EAI_NODATA))
264 loglevel = SYSLOG_LEVEL_ERROR;
265 do_log2(loglevel, "%s: Could not resolve hostname %.100s: %s",
266 __progname, name, ssh_gai_strerror(gaierr));
267 return NULL;
268 }
269 if (cname != NULL && res->ai_canonname != NULL) {
270 if (strlcpy(cname, res->ai_canonname, clen) >= clen) {
271 ssh_error("%s: host \"%s\" cname \"%s\" too long (max %lu)",
272 __func__, name, res->ai_canonname, (u_long)clen);
273 if (clen > 0)
274 *cname = '\0';
275 }
276 }
277 return res;
278 }
279
280 /*
281 * Attempt to resolve a numeric host address / port to a single address.
282 * Returns a canonical address string.
283 * Returns NULL on failure.
284 * NB. this function must operate with a options having undefined members.
285 */
286 static struct addrinfo *
resolve_addr(const char * name,int port,char * caddr,size_t clen)287 resolve_addr(const char *name, int port, char *caddr, size_t clen)
288 {
289 char addr[NI_MAXHOST], strport[NI_MAXSERV];
290 struct addrinfo hints, *res;
291 int gaierr;
292
293 if (port <= 0)
294 port = default_ssh_port();
295 snprintf(strport, sizeof strport, "%u", port);
296 memset(&hints, 0, sizeof(hints));
297 hints.ai_family = options.address_family == -1 ?
298 AF_UNSPEC : options.address_family;
299 hints.ai_socktype = SOCK_STREAM;
300 hints.ai_flags = AI_NUMERICHOST|AI_NUMERICSERV;
301 if ((gaierr = getaddrinfo(name, strport, &hints, &res)) != 0) {
302 debug2("%s: could not resolve name %.100s as address: %s",
303 __func__, name, ssh_gai_strerror(gaierr));
304 return NULL;
305 }
306 if (res == NULL) {
307 debug("%s: getaddrinfo %.100s returned no addresses",
308 __func__, name);
309 return NULL;
310 }
311 if (res->ai_next != NULL) {
312 debug("%s: getaddrinfo %.100s returned multiple addresses",
313 __func__, name);
314 goto fail;
315 }
316 if ((gaierr = getnameinfo(res->ai_addr, res->ai_addrlen,
317 addr, sizeof(addr), NULL, 0, NI_NUMERICHOST)) != 0) {
318 debug("%s: Could not format address for name %.100s: %s",
319 __func__, name, ssh_gai_strerror(gaierr));
320 goto fail;
321 }
322 if (strlcpy(caddr, addr, clen) >= clen) {
323 ssh_error("%s: host \"%s\" addr \"%s\" too long (max %lu)",
324 __func__, name, addr, (u_long)clen);
325 if (clen > 0)
326 *caddr = '\0';
327 fail:
328 freeaddrinfo(res);
329 return NULL;
330 }
331 return res;
332 }
333
334 /*
335 * Check whether the cname is a permitted replacement for the hostname
336 * and perform the replacement if it is.
337 * NB. this function must operate with a options having undefined members.
338 */
339 static int
check_follow_cname(char ** namep,const char * cname)340 check_follow_cname(char **namep, const char *cname)
341 {
342 int i;
343 struct allowed_cname *rule;
344
345 if (*cname == '\0' || options.num_permitted_cnames == 0 ||
346 strcmp(*namep, cname) == 0)
347 return 0;
348 if (options.canonicalize_hostname == SSH_CANONICALISE_NO)
349 return 0;
350 /*
351 * Don't attempt to canonicalize names that will be interpreted by
352 * a proxy unless the user specifically requests so.
353 */
354 if (!option_clear_or_none(options.proxy_command) &&
355 options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS)
356 return 0;
357 debug3("%s: check \"%s\" CNAME \"%s\"", __func__, *namep, cname);
358 for (i = 0; i < options.num_permitted_cnames; i++) {
359 rule = options.permitted_cnames + i;
360 if (match_pattern_list(*namep, rule->source_list, 1) != 1 ||
361 match_pattern_list(cname, rule->target_list, 1) != 1)
362 continue;
363 verbose("Canonicalized DNS aliased hostname "
364 "\"%s\" => \"%s\"", *namep, cname);
365 free(*namep);
366 *namep = xstrdup(cname);
367 return 1;
368 }
369 return 0;
370 }
371
372 /*
373 * Attempt to resolve the supplied hostname after applying the user's
374 * canonicalization rules. Returns the address list for the host or NULL
375 * if no name was found after canonicalization.
376 * NB. this function must operate with a options having undefined members.
377 */
378 #if 0
379 static struct addrinfo *
380 resolve_canonicalize(char **hostp, int port)
381 {
382 int i, ndots;
383 char *cp, *fullhost, newname[NI_MAXHOST];
384 struct addrinfo *addrs;
385
386 if (options.canonicalize_hostname == SSH_CANONICALISE_NO)
387 return NULL;
388
389 /*
390 * Don't attempt to canonicalize names that will be interpreted by
391 * a proxy unless the user specifically requests so.
392 */
393 if (!option_clear_or_none(options.proxy_command) &&
394 options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS)
395 return NULL;
396
397 /* Try numeric hostnames first */
398 if ((addrs = resolve_addr(*hostp, port,
399 newname, sizeof(newname))) != NULL) {
400 debug2("%s: hostname %.100s is address", __func__, *hostp);
401 if (strcasecmp(*hostp, newname) != 0) {
402 debug2("%s: canonicalised address \"%s\" => \"%s\"",
403 __func__, *hostp, newname);
404 free(*hostp);
405 *hostp = xstrdup(newname);
406 }
407 return addrs;
408 }
409
410 /* Don't apply canonicalization to sufficiently-qualified hostnames */
411 ndots = 0;
412 for (cp = *hostp; *cp != '\0'; cp++) {
413 if (*cp == '.')
414 ndots++;
415 }
416 if (ndots > options.canonicalize_max_dots) {
417 debug3("%s: not canonicalizing hostname \"%s\" (max dots %d)",
418 __func__, *hostp, options.canonicalize_max_dots);
419 return NULL;
420 }
421 /* Attempt each supplied suffix */
422 for (i = 0; i < options.num_canonical_domains; i++) {
423 *newname = '\0';
424 xasprintf(&fullhost, "%s.%s.", *hostp,
425 options.canonical_domains[i]);
426 debug3("%s: attempting \"%s\" => \"%s\"", __func__,
427 *hostp, fullhost);
428 if ((addrs = resolve_host(fullhost, port, 0,
429 newname, sizeof(newname))) == NULL) {
430 free(fullhost);
431 continue;
432 }
433 /* Remove trailing '.' */
434 fullhost[strlen(fullhost) - 1] = '\0';
435 /* Follow CNAME if requested */
436 if (!check_follow_cname(&fullhost, newname)) {
437 debug("Canonicalized hostname \"%s\" => \"%s\"",
438 *hostp, fullhost);
439 }
440 free(*hostp);
441 *hostp = fullhost;
442 return addrs;
443 }
444 if (!options.canonicalize_fallback_local)
445 fatal("%s: Could not resolve host \"%s\"", __progname, *hostp);
446 debug2("%s: host %s not found in any suffix", __func__, *hostp);
447 return NULL;
448 }
449 #endif
450
451 /*
452 * Read per-user configuration file. Ignore the system wide config
453 * file if the user specifies a config file on the command line.
454 */
455 static void
process_config_files(const char * host_arg,struct passwd * pw,int post_canon)456 process_config_files(const char *host_arg, struct passwd *pw, int post_canon)
457 {
458 char buf[PATH_MAX];
459 int r;
460
461 if (config != NULL) {
462 if (strcasecmp(config, "none") != 0 &&
463 !read_config_file(config, pw, host, host_arg, &options,
464 SSHCONF_USERCONF | (post_canon ? SSHCONF_POSTCANON : 0)))
465 fatal("Can't open user config file %.100s: "
466 "%.100s", config, strerror(errno));
467 } else {
468 r = snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir,
469 _PATH_SSH_USER_CONFFILE);
470 if (r > 0 && (size_t)r < sizeof(buf))
471 (void)read_config_file(buf, pw, host, host_arg,
472 &options, SSHCONF_CHECKPERM | SSHCONF_USERCONF |
473 (post_canon ? SSHCONF_POSTCANON : 0));
474
475 /* Read systemwide configuration file after user config. */
476 (void)read_config_file(_PATH_HOST_CONFIG_FILE, pw,
477 host, host_arg, &options,
478 post_canon ? SSHCONF_POSTCANON : 0);
479 }
480 }
481
482 /* Rewrite the port number in an addrinfo list of addresses */
483 static void
set_addrinfo_port(struct addrinfo * addrs,int port)484 set_addrinfo_port(struct addrinfo *addrs, int port)
485 {
486 struct addrinfo *addr;
487
488 for (addr = addrs; addr != NULL; addr = addr->ai_next) {
489 switch (addr->ai_family) {
490 case AF_INET:
491 ((struct sockaddr_in *)addr->ai_addr)->
492 sin_port = htons(port);
493 break;
494 case AF_INET6:
495 ((struct sockaddr_in6 *)addr->ai_addr)->
496 sin6_port = htons(port);
497 break;
498 }
499 }
500 }
501
502 /*
503 * Main program for the ssh client.
504 */
505 int
main(int ac,char ** av)506 main(int ac, char **av)
507 {
508 int i, r, opt, exit_status, use_syslog, config_test = 0;
509 char *p, *cp, *line, *argv0, buf[PATH_MAX], *host_arg, *logfile;
510 char thishost[NI_MAXHOST], shorthost[NI_MAXHOST], portstr[NI_MAXSERV];
511 char cname[NI_MAXHOST];
512 struct stat st;
513 struct passwd *pw;
514 int timeout_ms;
515 extern int optind, optreset;
516 extern char *optarg;
517 struct Forward fwd;
518 struct addrinfo *addrs = NULL;
519 struct ssh_digest_ctx *md;
520 u_char conn_hash[SSH_DIGEST_MAX_LENGTH];
521 char *conn_hash_hex;
522
523 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
524 sanitise_stdfd();
525
526 __progname = ssh_get_progname(av[0]);
527
528 #ifndef HAVE_SETPROCTITLE
529 /* Prepare for later setproctitle emulation */
530 /* Save argv so it isn't clobbered by setproctitle() emulation */
531 saved_av = xcalloc(ac + 1, sizeof(*saved_av));
532 for (i = 0; i < ac; i++)
533 saved_av[i] = xstrdup(av[i]);
534 saved_av[i] = NULL;
535 compat_init_setproctitle(ac, av);
536 av = saved_av;
537 #endif
538
539 /*
540 * Discard other fds that are hanging around. These can cause problem
541 * with backgrounded ssh processes started by ControlPersist.
542 */
543 closefrom(STDERR_FILENO + 1);
544
545 /*
546 * Save the original real uid. It will be needed later (uid-swapping
547 * may clobber the real uid).
548 */
549 original_real_uid = getuid();
550 original_effective_uid = geteuid();
551
552 /*
553 * Use uid-swapping to give up root privileges for the duration of
554 * option processing. We will re-instantiate the rights when we are
555 * ready to create the privileged port, and will permanently drop
556 * them when the port has been created (actually, when the connection
557 * has been made, as we may need to create the port several times).
558 */
559 PRIV_END;
560
561 #ifdef HAVE_SETRLIMIT
562 /* If we are installed setuid root be careful to not drop core. */
563 if (original_real_uid != original_effective_uid) {
564 struct rlimit rlim;
565 rlim.rlim_cur = rlim.rlim_max = 0;
566 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
567 fatal("setrlimit failed: %.100s", strerror(errno));
568 }
569 #endif
570 /* Get user data. */
571 pw = getpwuid(original_real_uid);
572 if (!pw) {
573 logit("No user exists for uid %lu", (u_long)original_real_uid);
574 exit(255);
575 }
576 /* Take a copy of the returned structure. */
577 pw = pwcopy(pw);
578
579 /*
580 * Set our umask to something reasonable, as some files are created
581 * with the default umask. This will make them world-readable but
582 * writable only by the owner, which is ok for all files for which we
583 * don't set the modes explicitly.
584 */
585 umask(022);
586
587 /*
588 * Initialize option structure to indicate that no values have been
589 * set.
590 */
591 initialize_options(&options);
592
593 /* Parse command-line arguments. */
594 host = NULL;
595 use_syslog = 0;
596 logfile = NULL;
597 argv0 = av[0];
598
599 again:
600 while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx"
601 "ACD:E:F:GI:KL:MNO:PQ:R:S:TVw:W:XYy")) != -1) {
602 switch (opt) {
603 case '1':
604 options.protocol = SSH_PROTO_1;
605 break;
606 case '2':
607 options.protocol = SSH_PROTO_2;
608 break;
609 case '4':
610 options.address_family = AF_INET;
611 break;
612 case '6':
613 options.address_family = AF_INET6;
614 break;
615 case 'n':
616 stdin_null_flag = 1;
617 break;
618 case 'f':
619 fork_after_authentication_flag = 1;
620 stdin_null_flag = 1;
621 break;
622 case 'x':
623 options.forward_x11 = 0;
624 break;
625 case 'X':
626 options.forward_x11 = 1;
627 break;
628 case 'y':
629 use_syslog = 1;
630 break;
631 case 'E':
632 logfile = xstrdup(optarg);
633 break;
634 case 'G':
635 config_test = 1;
636 break;
637 case 'Y':
638 options.forward_x11 = 1;
639 options.forward_x11_trusted = 1;
640 break;
641 case 'g':
642 options.fwd_opts.gateway_ports = 1;
643 break;
644 case 'O':
645 if (stdio_forward_host != NULL)
646 fatal("Cannot specify multiplexing "
647 "command with -W");
648 else if (muxclient_command != 0)
649 fatal("Multiplexing command already specified");
650 if (strcmp(optarg, "check") == 0)
651 muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK;
652 else if (strcmp(optarg, "forward") == 0)
653 muxclient_command = SSHMUX_COMMAND_FORWARD;
654 else if (strcmp(optarg, "exit") == 0)
655 muxclient_command = SSHMUX_COMMAND_TERMINATE;
656 else if (strcmp(optarg, "stop") == 0)
657 muxclient_command = SSHMUX_COMMAND_STOP;
658 else if (strcmp(optarg, "cancel") == 0)
659 muxclient_command = SSHMUX_COMMAND_CANCEL_FWD;
660 else
661 fatal("Invalid multiplex command.");
662 break;
663 case 'P': /* deprecated */
664 options.use_privileged_port = 0;
665 break;
666 case 'Q':
667 cp = NULL;
668 if (strcmp(optarg, "cipher") == 0)
669 cp = cipher_alg_list('\n', 0);
670 else if (strcmp(optarg, "cipher-auth") == 0)
671 cp = cipher_alg_list('\n', 1);
672 else if (strcmp(optarg, "mac") == 0)
673 cp = mac_alg_list('\n');
674 else if (strcmp(optarg, "kex") == 0)
675 cp = kex_alg_list('\n');
676 else if (strcmp(optarg, "key") == 0)
677 cp = key_alg_list(0, 0);
678 else if (strcmp(optarg, "key-cert") == 0)
679 cp = key_alg_list(1, 0);
680 else if (strcmp(optarg, "key-plain") == 0)
681 cp = key_alg_list(0, 1);
682 else if (strcmp(optarg, "protocol-version") == 0) {
683 #ifdef WITH_SSH1
684 cp = xstrdup("1\n2");
685 #else
686 cp = xstrdup("2");
687 #endif
688 }
689 if (cp == NULL)
690 fatal("Unsupported query \"%s\"", optarg);
691 printf("%s\n", cp);
692 free(cp);
693 exit(0);
694 break;
695 case 'a':
696 options.forward_agent = 0;
697 break;
698 case 'A':
699 options.forward_agent = 1;
700 break;
701 case 'k':
702 options.gss_deleg_creds = 0;
703 break;
704 case 'K':
705 options.gss_authentication = 1;
706 options.gss_deleg_creds = 1;
707 break;
708 case 'i':
709 if (stat(optarg, &st) < 0) {
710 fprintf(stderr, "Warning: Identity file %s "
711 "not accessible: %s.\n", optarg,
712 strerror(errno));
713 break;
714 }
715 add_identity_file(&options, NULL, optarg, 1);
716 break;
717 case 'I':
718 #ifdef ENABLE_PKCS11
719 options.pkcs11_provider = xstrdup(optarg);
720 #else
721 fprintf(stderr, "no support for PKCS#11.\n");
722 #endif
723 break;
724 case 't':
725 if (options.request_tty == REQUEST_TTY_YES)
726 options.request_tty = REQUEST_TTY_FORCE;
727 else
728 options.request_tty = REQUEST_TTY_YES;
729 break;
730 case 'v':
731 if (debug_flag == 0) {
732 debug_flag = 1;
733 options.log_level = SYSLOG_LEVEL_DEBUG1;
734 } else {
735 if (options.log_level < SYSLOG_LEVEL_DEBUG3)
736 options.log_level++;
737 }
738 break;
739 case 'V':
740 fprintf(stderr, "%s, %s\n",
741 SSH_RELEASE,
742 #ifdef WITH_OPENSSL
743 SSLeay_version(SSLEAY_VERSION)
744 #else
745 "without OpenSSL"
746 #endif
747 );
748 if (opt == 'V')
749 exit(0);
750 break;
751 case 'w':
752 if (options.tun_open == -1)
753 options.tun_open = SSH_TUNMODE_DEFAULT;
754 options.tun_local = a2tun(optarg, &options.tun_remote);
755 if (options.tun_local == SSH_TUNID_ERR) {
756 fprintf(stderr,
757 "Bad tun device '%s'\n", optarg);
758 exit(255);
759 }
760 break;
761 case 'W':
762 if (stdio_forward_host != NULL)
763 fatal("stdio forward already specified");
764 if (muxclient_command != 0)
765 fatal("Cannot specify stdio forward with -O");
766 if (parse_forward(&fwd, optarg, 1, 0)) {
767 stdio_forward_host = fwd.listen_host;
768 stdio_forward_port = fwd.listen_port;
769 free(fwd.connect_host);
770 } else {
771 fprintf(stderr,
772 "Bad stdio forwarding specification '%s'\n",
773 optarg);
774 exit(255);
775 }
776 options.request_tty = REQUEST_TTY_NO;
777 no_shell_flag = 1;
778 options.clear_forwardings = 1;
779 options.exit_on_forward_failure = 1;
780 break;
781 case 'q':
782 options.log_level = SYSLOG_LEVEL_QUIET;
783 break;
784 case 'e':
785 if (optarg[0] == '^' && optarg[2] == 0 &&
786 (u_char) optarg[1] >= 64 &&
787 (u_char) optarg[1] < 128)
788 options.escape_char = (u_char) optarg[1] & 31;
789 else if (strlen(optarg) == 1)
790 options.escape_char = (u_char) optarg[0];
791 else if (strcmp(optarg, "none") == 0)
792 options.escape_char = SSH_ESCAPECHAR_NONE;
793 else {
794 fprintf(stderr, "Bad escape character '%s'.\n",
795 optarg);
796 exit(255);
797 }
798 break;
799 case 'c':
800 if (ciphers_valid(*optarg == '+' ?
801 optarg + 1 : optarg)) {
802 /* SSH2 only */
803 options.ciphers = xstrdup(optarg);
804 options.cipher = SSH_CIPHER_INVALID;
805 break;
806 }
807 /* SSH1 only */
808 options.cipher = cipher_number(optarg);
809 if (options.cipher == -1) {
810 fprintf(stderr, "Unknown cipher type '%s'\n",
811 optarg);
812 exit(255);
813 }
814 if (options.cipher == SSH_CIPHER_3DES)
815 options.ciphers = xstrdup("3des-cbc");
816 else if (options.cipher == SSH_CIPHER_BLOWFISH)
817 options.ciphers = xstrdup("blowfish-cbc");
818 else
819 options.ciphers = xstrdup(KEX_CLIENT_ENCRYPT);
820 break;
821 case 'm':
822 if (mac_valid(optarg))
823 options.macs = xstrdup(optarg);
824 else {
825 fprintf(stderr, "Unknown mac type '%s'\n",
826 optarg);
827 exit(255);
828 }
829 break;
830 case 'M':
831 if (options.control_master == SSHCTL_MASTER_YES)
832 options.control_master = SSHCTL_MASTER_ASK;
833 else
834 options.control_master = SSHCTL_MASTER_YES;
835 break;
836 case 'p':
837 options.port = a2port(optarg);
838 if (options.port <= 0) {
839 fprintf(stderr, "Bad port '%s'\n", optarg);
840 exit(255);
841 }
842 break;
843 case 'l':
844 options.user = optarg;
845 break;
846
847 case 'L':
848 if (parse_forward(&fwd, optarg, 0, 0))
849 add_local_forward(&options, &fwd);
850 else {
851 fprintf(stderr,
852 "Bad local forwarding specification '%s'\n",
853 optarg);
854 exit(255);
855 }
856 break;
857
858 case 'R':
859 if (parse_forward(&fwd, optarg, 0, 1)) {
860 add_remote_forward(&options, &fwd);
861 } else {
862 fprintf(stderr,
863 "Bad remote forwarding specification "
864 "'%s'\n", optarg);
865 exit(255);
866 }
867 break;
868
869 case 'D':
870 if (parse_forward(&fwd, optarg, 1, 0)) {
871 add_local_forward(&options, &fwd);
872 } else {
873 fprintf(stderr,
874 "Bad dynamic forwarding specification "
875 "'%s'\n", optarg);
876 exit(255);
877 }
878 break;
879
880 case 'C':
881 options.compression = 1;
882 break;
883 case 'N':
884 no_shell_flag = 1;
885 options.request_tty = REQUEST_TTY_NO;
886 break;
887 case 'T':
888 options.request_tty = REQUEST_TTY_NO;
889 break;
890 case 'o':
891 line = xstrdup(optarg);
892 if (process_config_line(&options, pw,
893 host ? host : "", host ? host : "", line,
894 "command-line", 0, NULL, SSHCONF_USERCONF) != 0)
895 exit(255);
896 free(line);
897 break;
898 case 's':
899 subsystem_flag = 1;
900 break;
901 case 'S':
902 if (options.control_path != NULL)
903 free(options.control_path);
904 options.control_path = xstrdup(optarg);
905 break;
906 case 'b':
907 options.bind_address = optarg;
908 break;
909 case 'F':
910 config = optarg;
911 break;
912 default:
913 usage();
914 }
915 }
916
917 ac -= optind;
918 av += optind;
919
920 if (ac > 0 && !host) {
921 if (strrchr(*av, '@')) {
922 p = xstrdup(*av);
923 cp = strrchr(p, '@');
924 if (cp == NULL || cp == p)
925 usage();
926 options.user = p;
927 *cp = '\0';
928 host = xstrdup(++cp);
929 } else
930 host = xstrdup(*av);
931 if (ac > 1) {
932 optind = optreset = 1;
933 goto again;
934 }
935 ac--, av++;
936 }
937
938 /* Check that we got a host name. */
939 if (!host)
940 usage();
941
942 host_arg = xstrdup(host);
943
944 #ifdef WITH_OPENSSL
945 OpenSSL_add_all_algorithms();
946 ERR_load_crypto_strings();
947 #endif
948
949 /* Initialize the command to execute on remote host. */
950 buffer_init(&command);
951
952 /*
953 * Save the command to execute on the remote host in a buffer. There
954 * is no limit on the length of the command, except by the maximum
955 * packet size. Also sets the tty flag if there is no command.
956 */
957 if (!ac) {
958 /* No command specified - execute shell on a tty. */
959 if (subsystem_flag) {
960 fprintf(stderr,
961 "You must specify a subsystem to invoke.\n");
962 usage();
963 }
964 } else {
965 /* A command has been specified. Store it into the buffer. */
966 for (i = 0; i < ac; i++) {
967 if (i)
968 buffer_append(&command, " ", 1);
969 buffer_append(&command, av[i], strlen(av[i]));
970 }
971 }
972
973 /* Cannot fork to background if no command. */
974 if (fork_after_authentication_flag && buffer_len(&command) == 0 &&
975 !no_shell_flag)
976 fatal("Cannot fork into background without a command "
977 "to execute.");
978
979 /*
980 * Initialize "log" output. Since we are the client all output
981 * goes to stderr unless otherwise specified by -y or -E.
982 */
983 if (use_syslog && logfile != NULL)
984 fatal("Can't specify both -y and -E");
985 if (logfile != NULL) {
986 log_redirect_stderr_to(logfile);
987 free(logfile);
988 }
989 log_init(argv0,
990 options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level,
991 SYSLOG_FACILITY_USER, !use_syslog);
992
993 if (debug_flag)
994 logit("%s, %s", SSH_RELEASE,
995 #ifdef WITH_OPENSSL
996 SSLeay_version(SSLEAY_VERSION)
997 #else
998 "without OpenSSL"
999 #endif
1000 );
1001
1002 /* Parse the configuration files */
1003 process_config_files(host_arg, pw, 0);
1004
1005 /* Hostname canonicalisation needs a few options filled. */
1006 fill_default_options_for_canonicalization(&options);
1007
1008 /* If the user has replaced the hostname then take it into use now */
1009 if (options.hostname != NULL) {
1010 /* NB. Please keep in sync with readconf.c:match_cfg_line() */
1011 cp = percent_expand(options.hostname,
1012 "h", host, (char *)NULL);
1013 free(host);
1014 host = cp;
1015 free(options.hostname);
1016 options.hostname = xstrdup(host);
1017 }
1018
1019 /* If canonicalization requested then try to apply it */
1020 lowercase(host);
1021 if (options.canonicalize_hostname != SSH_CANONICALISE_NO)
1022 addrs = resolve_canonicalize(&host, options.port);
1023
1024 /*
1025 * If CanonicalizePermittedCNAMEs have been specified but
1026 * other canonicalization did not happen (by not being requested
1027 * or by failing with fallback) then the hostname may still be changed
1028 * as a result of CNAME following.
1029 *
1030 * Try to resolve the bare hostname name using the system resolver's
1031 * usual search rules and then apply the CNAME follow rules.
1032 *
1033 * Skip the lookup if a ProxyCommand is being used unless the user
1034 * has specifically requested canonicalisation for this case via
1035 * CanonicalizeHostname=always
1036 */
1037 if (addrs == NULL && options.num_permitted_cnames != 0 &&
1038 (option_clear_or_none(options.proxy_command) ||
1039 options.canonicalize_hostname == SSH_CANONICALISE_ALWAYS)) {
1040 if ((addrs = resolve_host(host, options.port,
1041 option_clear_or_none(options.proxy_command),
1042 cname, sizeof(cname))) == NULL) {
1043 /* Don't fatal proxied host names not in the DNS */
1044 if (option_clear_or_none(options.proxy_command))
1045 cleanup_exit(255); /* logged in resolve_host */
1046 } else
1047 check_follow_cname(&host, cname);
1048 }
1049
1050 /*
1051 * If canonicalisation is enabled then re-parse the configuration
1052 * files as new stanzas may match.
1053 */
1054 if (options.canonicalize_hostname != 0) {
1055 debug("Re-reading configuration after hostname "
1056 "canonicalisation");
1057 free(options.hostname);
1058 options.hostname = xstrdup(host);
1059 process_config_files(host_arg, pw, 1);
1060 /*
1061 * Address resolution happens early with canonicalisation
1062 * enabled and the port number may have changed since, so
1063 * reset it in address list
1064 */
1065 if (addrs != NULL && options.port > 0)
1066 set_addrinfo_port(addrs, options.port);
1067 }
1068
1069 /* Fill configuration defaults. */
1070 fill_default_options(&options);
1071
1072 if (options.port == 0)
1073 options.port = default_ssh_port();
1074 channel_set_af(options.address_family);
1075
1076 /* Tidy and check options */
1077 if (options.host_key_alias != NULL)
1078 lowercase(options.host_key_alias);
1079 if (options.proxy_command != NULL &&
1080 strcmp(options.proxy_command, "-") == 0 &&
1081 options.proxy_use_fdpass)
1082 fatal("ProxyCommand=- and ProxyUseFDPass are incompatible");
1083 if (options.control_persist &&
1084 options.update_hostkeys == SSH_UPDATE_HOSTKEYS_ASK) {
1085 debug("UpdateHostKeys=ask is incompatible with ControlPersist; "
1086 "disabling");
1087 options.update_hostkeys = 0;
1088 }
1089 #ifndef HAVE_CYGWIN
1090 if (original_effective_uid != 0)
1091 options.use_privileged_port = 0;
1092 #endif
1093
1094 /* reinit */
1095 log_init(argv0, options.log_level, SYSLOG_FACILITY_USER, !use_syslog);
1096
1097 if (options.request_tty == REQUEST_TTY_YES ||
1098 options.request_tty == REQUEST_TTY_FORCE)
1099 tty_flag = 1;
1100
1101 /* Allocate a tty by default if no command specified. */
1102 if (buffer_len(&command) == 0)
1103 tty_flag = options.request_tty != REQUEST_TTY_NO;
1104
1105 /* Force no tty */
1106 if (options.request_tty == REQUEST_TTY_NO || muxclient_command != 0)
1107 tty_flag = 0;
1108 /* Do not allocate a tty if stdin is not a tty. */
1109 if ((!isatty(fileno(stdin)) || stdin_null_flag) &&
1110 options.request_tty != REQUEST_TTY_FORCE) {
1111 if (tty_flag)
1112 logit("Pseudo-terminal will not be allocated because "
1113 "stdin is not a terminal.");
1114 tty_flag = 0;
1115 }
1116
1117 seed_rng();
1118
1119 if (options.user == NULL)
1120 options.user = xstrdup(pw->pw_name);
1121
1122 if (gethostname(thishost, sizeof(thishost)) == -1)
1123 fatal("gethostname: %s", strerror(errno));
1124 strlcpy(shorthost, thishost, sizeof(shorthost));
1125 shorthost[strcspn(thishost, ".")] = '\0';
1126 snprintf(portstr, sizeof(portstr), "%d", options.port);
1127
1128 if ((md = ssh_digest_start(SSH_DIGEST_SHA1)) == NULL ||
1129 ssh_digest_update(md, thishost, strlen(thishost)) < 0 ||
1130 ssh_digest_update(md, host, strlen(host)) < 0 ||
1131 ssh_digest_update(md, portstr, strlen(portstr)) < 0 ||
1132 ssh_digest_update(md, options.user, strlen(options.user)) < 0 ||
1133 ssh_digest_final(md, conn_hash, sizeof(conn_hash)) < 0)
1134 fatal("%s: mux digest failed", __func__);
1135 ssh_digest_free(md);
1136 conn_hash_hex = tohex(conn_hash, ssh_digest_bytes(SSH_DIGEST_SHA1));
1137
1138 if (options.local_command != NULL) {
1139 debug3("expanding LocalCommand: %s", options.local_command);
1140 cp = options.local_command;
1141 options.local_command = percent_expand(cp,
1142 "C", conn_hash_hex,
1143 "L", shorthost,
1144 "d", pw->pw_dir,
1145 "h", host,
1146 "l", thishost,
1147 "n", host_arg,
1148 "p", portstr,
1149 "r", options.user,
1150 "u", pw->pw_name,
1151 (char *)NULL);
1152 debug3("expanded LocalCommand: %s", options.local_command);
1153 free(cp);
1154 }
1155
1156 if (options.control_path != NULL) {
1157 cp = tilde_expand_filename(options.control_path,
1158 original_real_uid);
1159 free(options.control_path);
1160 options.control_path = percent_expand(cp,
1161 "C", conn_hash_hex,
1162 "L", shorthost,
1163 "h", host,
1164 "l", thishost,
1165 "n", host_arg,
1166 "p", portstr,
1167 "r", options.user,
1168 "u", pw->pw_name,
1169 (char *)NULL);
1170 free(cp);
1171 }
1172 free(conn_hash_hex);
1173
1174 if (config_test) {
1175 dump_client_config(&options, host);
1176 exit(0);
1177 }
1178
1179 if (muxclient_command != 0 && options.control_path == NULL)
1180 fatal("No ControlPath specified for \"-O\" command");
1181 if (options.control_path != NULL)
1182 muxclient(options.control_path);
1183
1184 /*
1185 * If hostname canonicalisation was not enabled, then we may not
1186 * have yet resolved the hostname. Do so now.
1187 */
1188 if (addrs == NULL && options.proxy_command == NULL) {
1189 if ((addrs = resolve_host(host, options.port, 1,
1190 cname, sizeof(cname))) == NULL)
1191 cleanup_exit(255); /* resolve_host logs the error */
1192 }
1193
1194 timeout_ms = options.connection_timeout * 1000;
1195
1196 /* Open a connection to the remote host. */
1197 if (ssh_connect(host, addrs, &hostaddr, options.port,
1198 options.address_family, options.connection_attempts,
1199 &timeout_ms, options.tcp_keep_alive,
1200 options.use_privileged_port) != 0)
1201 exit(255);
1202
1203 if (addrs != NULL)
1204 freeaddrinfo(addrs);
1205
1206 packet_set_timeout(options.server_alive_interval,
1207 options.server_alive_count_max);
1208
1209 if (timeout_ms > 0)
1210 debug3("timeout: %d ms remain after connect", timeout_ms);
1211
1212 /*
1213 * If we successfully made the connection, load the host private key
1214 * in case we will need it later for combined rsa-rhosts
1215 * authentication. This must be done before releasing extra
1216 * privileges, because the file is only readable by root.
1217 * If we cannot access the private keys, load the public keys
1218 * instead and try to execute the ssh-keysign helper instead.
1219 */
1220 sensitive_data.nkeys = 0;
1221 sensitive_data.keys = NULL;
1222 sensitive_data.external_keysign = 0;
1223 if (options.rhosts_rsa_authentication ||
1224 options.hostbased_authentication) {
1225 sensitive_data.nkeys = 9;
1226 sensitive_data.keys = xcalloc(sensitive_data.nkeys,
1227 sizeof(Key));
1228 for (i = 0; i < sensitive_data.nkeys; i++)
1229 sensitive_data.keys[i] = NULL;
1230
1231 PRIV_START;
1232 sensitive_data.keys[0] = key_load_private_type(KEY_RSA1,
1233 _PATH_HOST_KEY_FILE, "", NULL, NULL);
1234 #ifdef OPENSSL_HAS_ECC
1235 sensitive_data.keys[1] = key_load_private_cert(KEY_ECDSA,
1236 _PATH_HOST_ECDSA_KEY_FILE, "", NULL);
1237 #endif
1238 sensitive_data.keys[2] = key_load_private_cert(KEY_ED25519,
1239 _PATH_HOST_ED25519_KEY_FILE, "", NULL);
1240 sensitive_data.keys[3] = key_load_private_cert(KEY_RSA,
1241 _PATH_HOST_RSA_KEY_FILE, "", NULL);
1242 sensitive_data.keys[4] = key_load_private_cert(KEY_DSA,
1243 _PATH_HOST_DSA_KEY_FILE, "", NULL);
1244 #ifdef OPENSSL_HAS_ECC
1245 sensitive_data.keys[5] = key_load_private_type(KEY_ECDSA,
1246 _PATH_HOST_ECDSA_KEY_FILE, "", NULL, NULL);
1247 #endif
1248 sensitive_data.keys[6] = key_load_private_type(KEY_ED25519,
1249 _PATH_HOST_ED25519_KEY_FILE, "", NULL, NULL);
1250 sensitive_data.keys[7] = key_load_private_type(KEY_RSA,
1251 _PATH_HOST_RSA_KEY_FILE, "", NULL, NULL);
1252 sensitive_data.keys[8] = key_load_private_type(KEY_DSA,
1253 _PATH_HOST_DSA_KEY_FILE, "", NULL, NULL);
1254 PRIV_END;
1255
1256 if (options.hostbased_authentication == 1 &&
1257 sensitive_data.keys[0] == NULL &&
1258 sensitive_data.keys[5] == NULL &&
1259 sensitive_data.keys[6] == NULL &&
1260 sensitive_data.keys[7] == NULL &&
1261 sensitive_data.keys[8] == NULL) {
1262 #ifdef OPENSSL_HAS_ECC
1263 sensitive_data.keys[1] = key_load_cert(
1264 _PATH_HOST_ECDSA_KEY_FILE);
1265 #endif
1266 sensitive_data.keys[2] = key_load_cert(
1267 _PATH_HOST_ED25519_KEY_FILE);
1268 sensitive_data.keys[3] = key_load_cert(
1269 _PATH_HOST_RSA_KEY_FILE);
1270 sensitive_data.keys[4] = key_load_cert(
1271 _PATH_HOST_DSA_KEY_FILE);
1272 #ifdef OPENSSL_HAS_ECC
1273 sensitive_data.keys[5] = key_load_public(
1274 _PATH_HOST_ECDSA_KEY_FILE, NULL);
1275 #endif
1276 sensitive_data.keys[6] = key_load_public(
1277 _PATH_HOST_ED25519_KEY_FILE, NULL);
1278 sensitive_data.keys[7] = key_load_public(
1279 _PATH_HOST_RSA_KEY_FILE, NULL);
1280 sensitive_data.keys[8] = key_load_public(
1281 _PATH_HOST_DSA_KEY_FILE, NULL);
1282 sensitive_data.external_keysign = 1;
1283 }
1284 }
1285 /*
1286 * Get rid of any extra privileges that we may have. We will no
1287 * longer need them. Also, extra privileges could make it very hard
1288 * to read identity files and other non-world-readable files from the
1289 * user's home directory if it happens to be on a NFS volume where
1290 * root is mapped to nobody.
1291 */
1292 if (original_effective_uid == 0) {
1293 PRIV_START;
1294 permanently_set_uid(pw);
1295 }
1296
1297 /*
1298 * Now that we are back to our own permissions, create ~/.ssh
1299 * directory if it doesn't already exist.
1300 */
1301 if (config == NULL) {
1302 r = snprintf(buf, sizeof buf, "%s%s%s", pw->pw_dir,
1303 strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR);
1304 if (r > 0 && (size_t)r < sizeof(buf) && stat(buf, &st) < 0) {
1305 #ifdef WITH_SELINUX
1306 ssh_selinux_setfscreatecon(buf);
1307 #endif
1308 if (mkdir(buf, 0700) < 0)
1309 ssh_error("Could not create directory '%.200s'.",
1310 buf);
1311 #ifdef WITH_SELINUX
1312 ssh_selinux_setfscreatecon(NULL);
1313 #endif
1314 }
1315 }
1316 /* load options.identity_files */
1317 load_public_identity_files();
1318
1319 /* Expand ~ in known host file names. */
1320 tilde_expand_paths(options.system_hostfiles,
1321 options.num_system_hostfiles);
1322 tilde_expand_paths(options.user_hostfiles, options.num_user_hostfiles);
1323
1324 signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */
1325 signal(SIGCHLD, main_sigchld_handler);
1326
1327 /* Log into the remote system. Never returns if the login fails. */
1328 ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr,
1329 options.port, pw, timeout_ms);
1330
1331 if (packet_connection_is_on_socket()) {
1332 verbose("Authenticated to %s ([%s]:%d).", host,
1333 get_remote_ipaddr(), get_remote_port());
1334 } else {
1335 verbose("Authenticated to %s (via proxy).", host);
1336 }
1337
1338 /* We no longer need the private host keys. Clear them now. */
1339 if (sensitive_data.nkeys != 0) {
1340 for (i = 0; i < sensitive_data.nkeys; i++) {
1341 if (sensitive_data.keys[i] != NULL) {
1342 /* Destroys contents safely */
1343 debug3("clear hostkey %d", i);
1344 key_free(sensitive_data.keys[i]);
1345 sensitive_data.keys[i] = NULL;
1346 }
1347 }
1348 free(sensitive_data.keys);
1349 }
1350 for (i = 0; i < options.num_identity_files; i++) {
1351 free(options.identity_files[i]);
1352 options.identity_files[i] = NULL;
1353 if (options.identity_keys[i]) {
1354 key_free(options.identity_keys[i]);
1355 options.identity_keys[i] = NULL;
1356 }
1357 }
1358
1359 exit_status = compat20 ? ssh_session2() : ssh_session();
1360 packet_close();
1361
1362 if (options.control_path != NULL && muxserver_sock != -1)
1363 unlink(options.control_path);
1364
1365 /* Kill ProxyCommand if it is running. */
1366 ssh_kill_proxy_command();
1367
1368 return exit_status;
1369 }
1370
1371 static void
control_persist_detach(void)1372 control_persist_detach(void)
1373 {
1374 pid_t pid;
1375 int devnull;
1376
1377 debug("%s: backgrounding master process", __func__);
1378
1379 /*
1380 * master (current process) into the background, and make the
1381 * foreground process a client of the backgrounded master.
1382 */
1383 switch ((pid = fork())) {
1384 case -1:
1385 fatal("%s: fork: %s", __func__, strerror(errno));
1386 case 0:
1387 /* Child: master process continues mainloop */
1388 break;
1389 default:
1390 /* Parent: set up mux slave to connect to backgrounded master */
1391 debug2("%s: background process is %ld", __func__, (long)pid);
1392 stdin_null_flag = ostdin_null_flag;
1393 options.request_tty = orequest_tty;
1394 tty_flag = otty_flag;
1395 close(muxserver_sock);
1396 muxserver_sock = -1;
1397 options.control_master = SSHCTL_MASTER_NO;
1398 muxclient(options.control_path);
1399 /* muxclient() doesn't return on success. */
1400 fatal("Failed to connect to new control master");
1401 }
1402 if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
1403 ssh_error("%s: open(\"/dev/null\"): %s", __func__,
1404 strerror(errno));
1405 } else {
1406 if (dup2(devnull, STDIN_FILENO) == -1 ||
1407 dup2(devnull, STDOUT_FILENO) == -1)
1408 ssh_error("%s: dup2: %s", __func__, strerror(errno));
1409 if (devnull > STDERR_FILENO)
1410 close(devnull);
1411 }
1412 daemon(1, 1);
1413 setproctitle("%s [mux]", options.control_path);
1414 }
1415
1416 /* Do fork() after authentication. Used by "ssh -f" */
1417 static void
fork_postauth(void)1418 fork_postauth(void)
1419 {
1420 if (need_controlpersist_detach)
1421 control_persist_detach();
1422 debug("forking to background");
1423 fork_after_authentication_flag = 0;
1424 if (daemon(1, 1) < 0)
1425 fatal("daemon() failed: %.200s", strerror(errno));
1426 }
1427
1428 /* Callback for remote forward global requests */
1429 static void
ssh_confirm_remote_forward(int type,u_int32_t seq,void * ctxt)1430 ssh_confirm_remote_forward(int type, u_int32_t seq, void *ctxt)
1431 {
1432 struct Forward *rfwd = (struct Forward *)ctxt;
1433
1434 /* XXX verbose() on failure? */
1435 debug("remote forward %s for: listen %s%s%d, connect %s:%d",
1436 type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure",
1437 rfwd->listen_path ? rfwd->listen_path :
1438 rfwd->listen_host ? rfwd->listen_host : "",
1439 (rfwd->listen_path || rfwd->listen_host) ? ":" : "",
1440 rfwd->listen_port, rfwd->connect_path ? rfwd->connect_path :
1441 rfwd->connect_host, rfwd->connect_port);
1442 if (rfwd->listen_path == NULL && rfwd->listen_port == 0) {
1443 if (type == SSH2_MSG_REQUEST_SUCCESS) {
1444 rfwd->allocated_port = packet_get_int();
1445 logit("Allocated port %u for remote forward to %s:%d",
1446 rfwd->allocated_port,
1447 rfwd->connect_host, rfwd->connect_port);
1448 channel_update_permitted_opens(rfwd->handle,
1449 rfwd->allocated_port);
1450 } else {
1451 channel_update_permitted_opens(rfwd->handle, -1);
1452 }
1453 }
1454
1455 if (type == SSH2_MSG_REQUEST_FAILURE) {
1456 if (options.exit_on_forward_failure) {
1457 if (rfwd->listen_path != NULL)
1458 fatal("Error: remote port forwarding failed "
1459 "for listen path %s", rfwd->listen_path);
1460 else
1461 fatal("Error: remote port forwarding failed "
1462 "for listen port %d", rfwd->listen_port);
1463 } else {
1464 if (rfwd->listen_path != NULL)
1465 logit("Warning: remote port forwarding failed "
1466 "for listen path %s", rfwd->listen_path);
1467 else
1468 logit("Warning: remote port forwarding failed "
1469 "for listen port %d", rfwd->listen_port);
1470 }
1471 }
1472 if (++remote_forward_confirms_received == options.num_remote_forwards) {
1473 debug("All remote forwarding requests processed");
1474 if (fork_after_authentication_flag)
1475 fork_postauth();
1476 }
1477 }
1478
1479 static void
client_cleanup_stdio_fwd(int id,void * arg)1480 client_cleanup_stdio_fwd(int id, void *arg)
1481 {
1482 debug("stdio forwarding: done");
1483 cleanup_exit(0);
1484 }
1485
1486 static void
ssh_stdio_confirm(int id,int success,void * arg)1487 ssh_stdio_confirm(int id, int success, void *arg)
1488 {
1489 if (!success)
1490 fatal("stdio forwarding failed");
1491 }
1492
1493 static void
ssh_init_stdio_forwarding(void)1494 ssh_init_stdio_forwarding(void)
1495 {
1496 Channel *c;
1497 int in, out;
1498
1499 if (stdio_forward_host == NULL)
1500 return;
1501 if (!compat20)
1502 fatal("stdio forwarding require Protocol 2");
1503
1504 debug3("%s: %s:%d", __func__, stdio_forward_host, stdio_forward_port);
1505
1506 if ((in = dup(STDIN_FILENO)) < 0 ||
1507 (out = dup(STDOUT_FILENO)) < 0)
1508 fatal("channel_connect_stdio_fwd: dup() in/out failed");
1509 if ((c = channel_connect_stdio_fwd(stdio_forward_host,
1510 stdio_forward_port, in, out)) == NULL)
1511 fatal("%s: channel_connect_stdio_fwd failed", __func__);
1512 channel_register_cleanup(c->self, client_cleanup_stdio_fwd, 0);
1513 channel_register_open_confirm(c->self, ssh_stdio_confirm, NULL);
1514 }
1515
1516 static void
ssh_init_forwarding(void)1517 ssh_init_forwarding(void)
1518 {
1519 int success = 0;
1520 int i;
1521
1522 /* Initiate local TCP/IP port forwardings. */
1523 for (i = 0; i < options.num_local_forwards; i++) {
1524 debug("Local connections to %.200s:%d forwarded to remote "
1525 "address %.200s:%d",
1526 (options.local_forwards[i].listen_path != NULL) ?
1527 options.local_forwards[i].listen_path :
1528 (options.local_forwards[i].listen_host == NULL) ?
1529 (options.fwd_opts.gateway_ports ? "*" : "LOCALHOST") :
1530 options.local_forwards[i].listen_host,
1531 options.local_forwards[i].listen_port,
1532 (options.local_forwards[i].connect_path != NULL) ?
1533 options.local_forwards[i].connect_path :
1534 options.local_forwards[i].connect_host,
1535 options.local_forwards[i].connect_port);
1536 success += channel_setup_local_fwd_listener(
1537 &options.local_forwards[i], &options.fwd_opts);
1538 }
1539 if (i > 0 && success != i && options.exit_on_forward_failure)
1540 fatal("Could not request local forwarding.");
1541 if (i > 0 && success == 0)
1542 ssh_error("Could not request local forwarding.");
1543
1544 /* Initiate remote TCP/IP port forwardings. */
1545 for (i = 0; i < options.num_remote_forwards; i++) {
1546 debug("Remote connections from %.200s:%d forwarded to "
1547 "local address %.200s:%d",
1548 (options.remote_forwards[i].listen_path != NULL) ?
1549 options.remote_forwards[i].listen_path :
1550 (options.remote_forwards[i].listen_host == NULL) ?
1551 "LOCALHOST" : options.remote_forwards[i].listen_host,
1552 options.remote_forwards[i].listen_port,
1553 (options.remote_forwards[i].connect_path != NULL) ?
1554 options.remote_forwards[i].connect_path :
1555 options.remote_forwards[i].connect_host,
1556 options.remote_forwards[i].connect_port);
1557 options.remote_forwards[i].handle =
1558 channel_request_remote_forwarding(
1559 &options.remote_forwards[i]);
1560 if (options.remote_forwards[i].handle < 0) {
1561 if (options.exit_on_forward_failure)
1562 fatal("Could not request remote forwarding.");
1563 else
1564 logit("Warning: Could not request remote "
1565 "forwarding.");
1566 } else {
1567 client_register_global_confirm(ssh_confirm_remote_forward,
1568 &options.remote_forwards[i]);
1569 }
1570 }
1571
1572 /* Initiate tunnel forwarding. */
1573 if (options.tun_open != SSH_TUNMODE_NO) {
1574 if (client_request_tun_fwd(options.tun_open,
1575 options.tun_local, options.tun_remote) == -1) {
1576 if (options.exit_on_forward_failure)
1577 fatal("Could not request tunnel forwarding.");
1578 else
1579 ssh_error("Could not request tunnel forwarding.");
1580 }
1581 }
1582 }
1583
1584 static void
check_agent_present(void)1585 check_agent_present(void)
1586 {
1587 int r;
1588
1589 if (options.forward_agent) {
1590 /* Clear agent forwarding if we don't have an agent. */
1591 if ((r = ssh_get_authentication_socket(NULL)) != 0) {
1592 options.forward_agent = 0;
1593 if (r != SSH_ERR_AGENT_NOT_PRESENT)
1594 debug("ssh_get_authentication_socket: %s",
1595 ssh_err(r));
1596 }
1597 }
1598 }
1599
1600 static int
ssh_session(void)1601 ssh_session(void)
1602 {
1603 int type;
1604 int interactive = 0;
1605 int have_tty = 0;
1606 struct winsize ws;
1607 char *cp;
1608 const char *display;
1609
1610 /* Enable compression if requested. */
1611 if (options.compression) {
1612 debug("Requesting compression at level %d.",
1613 options.compression_level);
1614
1615 if (options.compression_level < 1 ||
1616 options.compression_level > 9)
1617 fatal("Compression level must be from 1 (fast) to "
1618 "9 (slow, best).");
1619
1620 /* Send the request. */
1621 packet_start(SSH_CMSG_REQUEST_COMPRESSION);
1622 packet_put_int(options.compression_level);
1623 packet_send();
1624 packet_write_wait();
1625 type = packet_read();
1626 if (type == SSH_SMSG_SUCCESS)
1627 packet_start_compression(options.compression_level);
1628 else if (type == SSH_SMSG_FAILURE)
1629 logit("Warning: Remote host refused compression.");
1630 else
1631 packet_disconnect("Protocol error waiting for "
1632 "compression response.");
1633 }
1634 /* Allocate a pseudo tty if appropriate. */
1635 if (tty_flag) {
1636 debug("Requesting pty.");
1637
1638 /* Start the packet. */
1639 packet_start(SSH_CMSG_REQUEST_PTY);
1640
1641 /* Store TERM in the packet. There is no limit on the
1642 length of the string. */
1643 cp = getenv("TERM");
1644 if (!cp)
1645 cp = "";
1646 packet_put_cstring(cp);
1647
1648 /* Store window size in the packet. */
1649 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
1650 memset(&ws, 0, sizeof(ws));
1651 packet_put_int((u_int)ws.ws_row);
1652 packet_put_int((u_int)ws.ws_col);
1653 packet_put_int((u_int)ws.ws_xpixel);
1654 packet_put_int((u_int)ws.ws_ypixel);
1655
1656 /* Store tty modes in the packet. */
1657 tty_make_modes(fileno(stdin), NULL);
1658
1659 /* Send the packet, and wait for it to leave. */
1660 packet_send();
1661 packet_write_wait();
1662
1663 /* Read response from the server. */
1664 type = packet_read();
1665 if (type == SSH_SMSG_SUCCESS) {
1666 interactive = 1;
1667 have_tty = 1;
1668 } else if (type == SSH_SMSG_FAILURE)
1669 logit("Warning: Remote host failed or refused to "
1670 "allocate a pseudo tty.");
1671 else
1672 packet_disconnect("Protocol error waiting for pty "
1673 "request response.");
1674 }
1675 /* Request X11 forwarding if enabled and DISPLAY is set. */
1676 display = getenv("DISPLAY");
1677 if (display == NULL && options.forward_x11)
1678 debug("X11 forwarding requested but DISPLAY not set");
1679 if (options.forward_x11 && display != NULL) {
1680 char *proto, *data;
1681 /* Get reasonable local authentication information. */
1682 client_x11_get_proto(display, options.xauth_location,
1683 options.forward_x11_trusted,
1684 options.forward_x11_timeout,
1685 &proto, &data);
1686 /* Request forwarding with authentication spoofing. */
1687 debug("Requesting X11 forwarding with authentication "
1688 "spoofing.");
1689 x11_request_forwarding_with_spoofing(0, display, proto,
1690 data, 0);
1691 /* Read response from the server. */
1692 type = packet_read();
1693 if (type == SSH_SMSG_SUCCESS) {
1694 interactive = 1;
1695 } else if (type == SSH_SMSG_FAILURE) {
1696 logit("Warning: Remote host denied X11 forwarding.");
1697 } else {
1698 packet_disconnect("Protocol error waiting for X11 "
1699 "forwarding");
1700 }
1701 }
1702 /* Tell the packet module whether this is an interactive session. */
1703 packet_set_interactive(interactive,
1704 options.ip_qos_interactive, options.ip_qos_bulk);
1705
1706 /* Request authentication agent forwarding if appropriate. */
1707 check_agent_present();
1708
1709 if (options.forward_agent) {
1710 debug("Requesting authentication agent forwarding.");
1711 auth_request_forwarding();
1712
1713 /* Read response from the server. */
1714 type = packet_read();
1715 packet_check_eom();
1716 if (type != SSH_SMSG_SUCCESS)
1717 logit("Warning: Remote host denied authentication agent forwarding.");
1718 }
1719
1720 /* Initiate port forwardings. */
1721 ssh_init_stdio_forwarding();
1722 ssh_init_forwarding();
1723
1724 /* Execute a local command */
1725 if (options.local_command != NULL &&
1726 options.permit_local_command)
1727 ssh_local_cmd(options.local_command);
1728
1729 /*
1730 * If requested and we are not interested in replies to remote
1731 * forwarding requests, then let ssh continue in the background.
1732 */
1733 if (fork_after_authentication_flag) {
1734 if (options.exit_on_forward_failure &&
1735 options.num_remote_forwards > 0) {
1736 debug("deferring postauth fork until remote forward "
1737 "confirmation received");
1738 } else
1739 fork_postauth();
1740 }
1741
1742 /*
1743 * If a command was specified on the command line, execute the
1744 * command now. Otherwise request the server to start a shell.
1745 */
1746 if (buffer_len(&command) > 0) {
1747 int len = buffer_len(&command);
1748 if (len > 900)
1749 len = 900;
1750 debug("Sending command: %.*s", len,
1751 (u_char *)buffer_ptr(&command));
1752 packet_start(SSH_CMSG_EXEC_CMD);
1753 packet_put_string(buffer_ptr(&command), buffer_len(&command));
1754 packet_send();
1755 packet_write_wait();
1756 } else {
1757 debug("Requesting shell.");
1758 packet_start(SSH_CMSG_EXEC_SHELL);
1759 packet_send();
1760 packet_write_wait();
1761 }
1762
1763 /* Enter the interactive session. */
1764 return client_loop(have_tty, tty_flag ?
1765 options.escape_char : SSH_ESCAPECHAR_NONE, 0);
1766 }
1767
1768 /* request pty/x11/agent/tcpfwd/shell for channel */
1769 static void
ssh_session2_setup(int id,int success,void * arg)1770 ssh_session2_setup(int id, int success, void *arg)
1771 {
1772 extern char **environ;
1773 const char *display;
1774 int interactive = tty_flag;
1775
1776 if (!success)
1777 return; /* No need for error message, channels code sens one */
1778
1779 display = getenv("DISPLAY");
1780 if (display == NULL && options.forward_x11)
1781 debug("X11 forwarding requested but DISPLAY not set");
1782 if (options.forward_x11 && display != NULL) {
1783 char *proto, *data;
1784 /* Get reasonable local authentication information. */
1785 client_x11_get_proto(display, options.xauth_location,
1786 options.forward_x11_trusted,
1787 options.forward_x11_timeout, &proto, &data);
1788 /* Request forwarding with authentication spoofing. */
1789 debug("Requesting X11 forwarding with authentication "
1790 "spoofing.");
1791 x11_request_forwarding_with_spoofing(id, display, proto,
1792 data, 1);
1793 client_expect_confirm(id, "X11 forwarding", CONFIRM_WARN);
1794 /* XXX exit_on_forward_failure */
1795 interactive = 1;
1796 }
1797
1798 check_agent_present();
1799 if (options.forward_agent) {
1800 debug("Requesting authentication agent forwarding.");
1801 channel_request_start(id, "auth-agent-req@openssh.com", 0);
1802 packet_send();
1803 }
1804
1805 /* Tell the packet module whether this is an interactive session. */
1806 packet_set_interactive(interactive,
1807 options.ip_qos_interactive, options.ip_qos_bulk);
1808
1809 client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"),
1810 NULL, fileno(stdin), &command, environ);
1811 }
1812
1813 /* open new channel for a session */
1814 static int
ssh_session2_open(void)1815 ssh_session2_open(void)
1816 {
1817 Channel *c;
1818 int window, packetmax, in, out, err;
1819
1820 if (stdin_null_flag) {
1821 in = open(_PATH_DEVNULL, O_RDONLY);
1822 } else {
1823 in = dup(STDIN_FILENO);
1824 }
1825 out = dup(STDOUT_FILENO);
1826 err = dup(STDERR_FILENO);
1827
1828 if (in < 0 || out < 0 || err < 0)
1829 fatal("dup() in/out/err failed");
1830
1831 /* enable nonblocking unless tty */
1832 if (!isatty(in))
1833 set_nonblock(in);
1834 if (!isatty(out))
1835 set_nonblock(out);
1836 if (!isatty(err))
1837 set_nonblock(err);
1838
1839 window = CHAN_SES_WINDOW_DEFAULT;
1840 packetmax = CHAN_SES_PACKET_DEFAULT;
1841 if (tty_flag) {
1842 window >>= 1;
1843 packetmax >>= 1;
1844 }
1845 c = channel_new(
1846 "session", SSH_CHANNEL_OPENING, in, out, err,
1847 window, packetmax, CHAN_EXTENDED_WRITE,
1848 "client-session", /*nonblock*/0);
1849
1850 debug3("ssh_session2_open: channel_new: %d", c->self);
1851
1852 channel_send_open(c->self);
1853 if (!no_shell_flag)
1854 channel_register_open_confirm(c->self,
1855 ssh_session2_setup, NULL);
1856
1857 return c->self;
1858 }
1859
1860 static int
ssh_session2(void)1861 ssh_session2(void)
1862 {
1863 int id = -1;
1864
1865 /* XXX should be pre-session */
1866 if (!options.control_persist)
1867 ssh_init_stdio_forwarding();
1868 ssh_init_forwarding();
1869
1870 /* Start listening for multiplex clients */
1871 muxserver_listen();
1872
1873 /*
1874 * If we are in control persist mode and have a working mux listen
1875 * socket, then prepare to background ourselves and have a foreground
1876 * client attach as a control slave.
1877 * NB. we must save copies of the flags that we override for
1878 * the backgrounding, since we defer attachment of the slave until
1879 * after the connection is fully established (in particular,
1880 * async rfwd replies have been received for ExitOnForwardFailure).
1881 */
1882 if (options.control_persist && muxserver_sock != -1) {
1883 ostdin_null_flag = stdin_null_flag;
1884 ono_shell_flag = no_shell_flag;
1885 orequest_tty = options.request_tty;
1886 otty_flag = tty_flag;
1887 stdin_null_flag = 1;
1888 no_shell_flag = 1;
1889 tty_flag = 0;
1890 if (!fork_after_authentication_flag)
1891 need_controlpersist_detach = 1;
1892 fork_after_authentication_flag = 1;
1893 }
1894 /*
1895 * ControlPersist mux listen socket setup failed, attempt the
1896 * stdio forward setup that we skipped earlier.
1897 */
1898 if (options.control_persist && muxserver_sock == -1)
1899 ssh_init_stdio_forwarding();
1900
1901 if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN))
1902 id = ssh_session2_open();
1903 else {
1904 packet_set_interactive(
1905 options.control_master == SSHCTL_MASTER_NO,
1906 options.ip_qos_interactive, options.ip_qos_bulk);
1907 }
1908
1909 /* If we don't expect to open a new session, then disallow it */
1910 if (options.control_master == SSHCTL_MASTER_NO &&
1911 (datafellows & SSH_NEW_OPENSSH)) {
1912 debug("Requesting no-more-sessions@openssh.com");
1913 packet_start(SSH2_MSG_GLOBAL_REQUEST);
1914 packet_put_cstring("no-more-sessions@openssh.com");
1915 packet_put_char(0);
1916 packet_send();
1917 }
1918
1919 /* Execute a local command */
1920 if (options.local_command != NULL &&
1921 options.permit_local_command)
1922 ssh_local_cmd(options.local_command);
1923
1924 /*
1925 * If requested and we are not interested in replies to remote
1926 * forwarding requests, then let ssh continue in the background.
1927 */
1928 if (fork_after_authentication_flag) {
1929 if (options.exit_on_forward_failure &&
1930 options.num_remote_forwards > 0) {
1931 debug("deferring postauth fork until remote forward "
1932 "confirmation received");
1933 } else
1934 fork_postauth();
1935 }
1936
1937 if (options.use_roaming)
1938 request_roaming();
1939
1940 return client_loop(tty_flag, tty_flag ?
1941 options.escape_char : SSH_ESCAPECHAR_NONE, id);
1942 }
1943
1944 #if 0
1945 static void
1946 load_public_identity_files(void)
1947 {
1948 char *filename, *cp, thishost[NI_MAXHOST];
1949 char *pwdir = NULL, *pwname = NULL;
1950 int i = 0;
1951 Key *public;
1952 struct passwd *pw;
1953 u_int n_ids;
1954 char *identity_files[SSH_MAX_IDENTITY_FILES];
1955 Key *identity_keys[SSH_MAX_IDENTITY_FILES];
1956 #ifdef ENABLE_PKCS11
1957 Key **keys;
1958 int nkeys;
1959 #endif /* PKCS11 */
1960
1961 n_ids = 0;
1962 memset(identity_files, 0, sizeof(identity_files));
1963 memset(identity_keys, 0, sizeof(identity_keys));
1964
1965 #ifdef ENABLE_PKCS11
1966 if (options.pkcs11_provider != NULL &&
1967 options.num_identity_files < SSH_MAX_IDENTITY_FILES &&
1968 (pkcs11_init(!options.batch_mode) == 0) &&
1969 (nkeys = pkcs11_add_provider(options.pkcs11_provider, NULL,
1970 &keys)) > 0) {
1971 for (i = 0; i < nkeys; i++) {
1972 if (n_ids >= SSH_MAX_IDENTITY_FILES) {
1973 key_free(keys[i]);
1974 continue;
1975 }
1976 identity_keys[n_ids] = keys[i];
1977 identity_files[n_ids] =
1978 xstrdup(options.pkcs11_provider); /* XXX */
1979 n_ids++;
1980 }
1981 free(keys);
1982 }
1983 #endif /* ENABLE_PKCS11 */
1984 if ((pw = getpwuid(original_real_uid)) == NULL)
1985 fatal("load_public_identity_files: getpwuid failed");
1986 pwname = xstrdup(pw->pw_name);
1987 pwdir = xstrdup(pw->pw_dir);
1988 if (gethostname(thishost, sizeof(thishost)) == -1)
1989 fatal("load_public_identity_files: gethostname: %s",
1990 strerror(errno));
1991 for (i = 0; i < options.num_identity_files; i++) {
1992 if (n_ids >= SSH_MAX_IDENTITY_FILES ||
1993 strcasecmp(options.identity_files[i], "none") == 0) {
1994 free(options.identity_files[i]);
1995 continue;
1996 }
1997 cp = tilde_expand_filename(options.identity_files[i],
1998 original_real_uid);
1999 filename = percent_expand(cp, "d", pwdir,
2000 "u", pwname, "l", thishost, "h", host,
2001 "r", options.user, (char *)NULL);
2002 free(cp);
2003 public = key_load_public(filename, NULL);
2004 debug("identity file %s type %d", filename,
2005 public ? public->type : -1);
2006 free(options.identity_files[i]);
2007 identity_files[n_ids] = filename;
2008 identity_keys[n_ids] = public;
2009
2010 if (++n_ids >= SSH_MAX_IDENTITY_FILES)
2011 continue;
2012
2013 /* Try to add the certificate variant too */
2014 xasprintf(&cp, "%s-cert", filename);
2015 public = key_load_public(cp, NULL);
2016 debug("identity file %s type %d", cp,
2017 public ? public->type : -1);
2018 if (public == NULL) {
2019 free(cp);
2020 continue;
2021 }
2022 if (!key_is_cert(public)) {
2023 debug("%s: key %s type %s is not a certificate",
2024 __func__, cp, key_type(public));
2025 key_free(public);
2026 free(cp);
2027 continue;
2028 }
2029 identity_keys[n_ids] = public;
2030 /* point to the original path, most likely the private key */
2031 identity_files[n_ids] = xstrdup(filename);
2032 n_ids++;
2033 }
2034 options.num_identity_files = n_ids;
2035 memcpy(options.identity_files, identity_files, sizeof(identity_files));
2036 memcpy(options.identity_keys, identity_keys, sizeof(identity_keys));
2037
2038 explicit_bzero(pwname, strlen(pwname));
2039 free(pwname);
2040 explicit_bzero(pwdir, strlen(pwdir));
2041 free(pwdir);
2042 }
2043 #endif
2044
2045 static void
main_sigchld_handler(int sig)2046 main_sigchld_handler(int sig)
2047 {
2048 int save_errno = errno;
2049 pid_t pid;
2050 int status;
2051
2052 while ((pid = waitpid(-1, &status, WNOHANG)) > 0 ||
2053 (pid < 0 && errno == EINTR))
2054 ;
2055
2056 signal(sig, main_sigchld_handler);
2057 errno = save_errno;
2058 }
2059