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