1 /* $OpenBSD: ssh.c,v 1.469 2017/11/01 00:04:15 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 <sys/types.h> 44 #include <sys/ioctl.h> 45 #include <sys/queue.h> 46 #include <sys/resource.h> 47 #include <sys/socket.h> 48 #include <sys/stat.h> 49 #include <sys/time.h> 50 #include <sys/wait.h> 51 52 #include <ctype.h> 53 #include <errno.h> 54 #include <fcntl.h> 55 #include <netdb.h> 56 #include <paths.h> 57 #include <pwd.h> 58 #include <signal.h> 59 #include <stddef.h> 60 #include <stdio.h> 61 #include <stdlib.h> 62 #include <string.h> 63 #include <unistd.h> 64 #include <limits.h> 65 #include <locale.h> 66 67 #ifdef WITH_OPENSSL 68 #include <openssl/evp.h> 69 #include <openssl/err.h> 70 #endif 71 72 #include "xmalloc.h" 73 #include "ssh.h" 74 #include "ssh2.h" 75 #include "canohost.h" 76 #include "compat.h" 77 #include "cipher.h" 78 #include "digest.h" 79 #include "packet.h" 80 #include "buffer.h" 81 #include "channels.h" 82 #include "key.h" 83 #include "authfd.h" 84 #include "authfile.h" 85 #include "pathnames.h" 86 #include "dispatch.h" 87 #include "clientloop.h" 88 #include "log.h" 89 #include "misc.h" 90 #include "readconf.h" 91 #include "sshconnect.h" 92 #include "kex.h" 93 #include "mac.h" 94 #include "sshpty.h" 95 #include "match.h" 96 #include "msg.h" 97 #include "uidswap.h" 98 #include "version.h" 99 #include "ssherr.h" 100 #include "myproposal.h" 101 102 #ifdef ENABLE_PKCS11 103 #include "ssh-pkcs11.h" 104 #endif 105 106 extern char *__progname; 107 108 /* Flag indicating whether debug mode is on. May be set on the command line. */ 109 int debug_flag = 0; 110 111 /* Flag indicating whether a tty should be requested */ 112 int tty_flag = 0; 113 114 /* don't exec a shell */ 115 int no_shell_flag = 0; 116 117 /* 118 * Flag indicating that nothing should be read from stdin. This can be set 119 * on the command line. 120 */ 121 int stdin_null_flag = 0; 122 123 /* 124 * Flag indicating that the current process should be backgrounded and 125 * a new slave launched in the foreground for ControlPersist. 126 */ 127 int need_controlpersist_detach = 0; 128 129 /* Copies of flags for ControlPersist foreground slave */ 130 int ostdin_null_flag, ono_shell_flag, otty_flag, orequest_tty; 131 132 /* 133 * Flag indicating that ssh should fork after authentication. This is useful 134 * so that the passphrase can be entered manually, and then ssh goes to the 135 * background. 136 */ 137 int fork_after_authentication_flag = 0; 138 139 /* 140 * General data structure for command line options and options configurable 141 * in configuration files. See readconf.h. 142 */ 143 Options options; 144 145 /* optional user configfile */ 146 char *config = NULL; 147 148 /* 149 * Name of the host we are connecting to. This is the name given on the 150 * command line, or the HostName specified for the user-supplied name in a 151 * configuration file. 152 */ 153 char *host; 154 155 /* Various strings used to to percent_expand() arguments */ 156 static char thishost[NI_MAXHOST], shorthost[NI_MAXHOST], portstr[NI_MAXSERV]; 157 static char uidstr[32], *host_arg, *conn_hash_hex; 158 159 /* socket address the host resolves to */ 160 struct sockaddr_storage hostaddr; 161 162 /* Private host keys. */ 163 Sensitive sensitive_data; 164 165 /* Original real UID. */ 166 uid_t original_real_uid; 167 uid_t original_effective_uid; 168 169 /* command to be executed */ 170 Buffer command; 171 172 /* Should we execute a command or invoke a subsystem? */ 173 int subsystem_flag = 0; 174 175 /* # of replies received for global requests */ 176 static int remote_forward_confirms_received = 0; 177 178 /* mux.c */ 179 extern int muxserver_sock; 180 extern u_int muxclient_command; 181 182 /* Prints a help message to the user. This function never returns. */ 183 184 static void 185 usage(void) 186 { 187 fprintf(stderr, 188 "usage: ssh [-46AaCfGgKkMNnqsTtVvXxYy] [-b bind_address] [-c cipher_spec]\n" 189 " [-D [bind_address:]port] [-E log_file] [-e escape_char]\n" 190 " [-F configfile] [-I pkcs11] [-i identity_file]\n" 191 " [-J [user@]host[:port]] [-L address] [-l login_name] [-m mac_spec]\n" 192 " [-O ctl_cmd] [-o option] [-p port] [-Q query_option] [-R address]\n" 193 " [-S ctl_path] [-W host:port] [-w local_tun[:remote_tun]]\n" 194 " destination [command]\n" 195 ); 196 exit(255); 197 } 198 199 static int ssh_session2(struct ssh *, struct passwd *); 200 static void load_public_identity_files(struct passwd *); 201 static void main_sigchld_handler(int); 202 203 /* ~/ expand a list of paths. NB. assumes path[n] is heap-allocated. */ 204 static void 205 tilde_expand_paths(char **paths, u_int num_paths) 206 { 207 u_int i; 208 char *cp; 209 210 for (i = 0; i < num_paths; i++) { 211 cp = tilde_expand_filename(paths[i], original_real_uid); 212 free(paths[i]); 213 paths[i] = cp; 214 } 215 } 216 217 /* 218 * Attempt to resolve a host name / port to a set of addresses and 219 * optionally return any CNAMEs encountered along the way. 220 * Returns NULL on failure. 221 * NB. this function must operate with a options having undefined members. 222 */ 223 static struct addrinfo * 224 resolve_host(const char *name, int port, int logerr, char *cname, size_t clen) 225 { 226 char strport[NI_MAXSERV]; 227 struct addrinfo hints, *res; 228 int gaierr, loglevel = SYSLOG_LEVEL_DEBUG1; 229 230 if (port <= 0) 231 port = default_ssh_port(); 232 233 snprintf(strport, sizeof strport, "%d", port); 234 memset(&hints, 0, sizeof(hints)); 235 hints.ai_family = options.address_family == -1 ? 236 AF_UNSPEC : options.address_family; 237 hints.ai_socktype = SOCK_STREAM; 238 if (cname != NULL) 239 hints.ai_flags = AI_CANONNAME; 240 if ((gaierr = getaddrinfo(name, strport, &hints, &res)) != 0) { 241 if (logerr || (gaierr != EAI_NONAME && gaierr != EAI_NODATA)) 242 loglevel = SYSLOG_LEVEL_ERROR; 243 do_log2(loglevel, "%s: Could not resolve hostname %.100s: %s", 244 __progname, name, ssh_gai_strerror(gaierr)); 245 return NULL; 246 } 247 if (cname != NULL && res->ai_canonname != NULL) { 248 if (strlcpy(cname, res->ai_canonname, clen) >= clen) { 249 error("%s: host \"%s\" cname \"%s\" too long (max %lu)", 250 __func__, name, res->ai_canonname, (u_long)clen); 251 if (clen > 0) 252 *cname = '\0'; 253 } 254 } 255 return res; 256 } 257 258 /* 259 * Attempt to resolve a numeric host address / port to a single address. 260 * Returns a canonical address string. 261 * Returns NULL on failure. 262 * NB. this function must operate with a options having undefined members. 263 */ 264 static struct addrinfo * 265 resolve_addr(const char *name, int port, char *caddr, size_t clen) 266 { 267 char addr[NI_MAXHOST], strport[NI_MAXSERV]; 268 struct addrinfo hints, *res; 269 int gaierr; 270 271 if (port <= 0) 272 port = default_ssh_port(); 273 snprintf(strport, sizeof strport, "%u", port); 274 memset(&hints, 0, sizeof(hints)); 275 hints.ai_family = options.address_family == -1 ? 276 AF_UNSPEC : options.address_family; 277 hints.ai_socktype = SOCK_STREAM; 278 hints.ai_flags = AI_NUMERICHOST|AI_NUMERICSERV; 279 if ((gaierr = getaddrinfo(name, strport, &hints, &res)) != 0) { 280 debug2("%s: could not resolve name %.100s as address: %s", 281 __func__, name, ssh_gai_strerror(gaierr)); 282 return NULL; 283 } 284 if (res == NULL) { 285 debug("%s: getaddrinfo %.100s returned no addresses", 286 __func__, name); 287 return NULL; 288 } 289 if (res->ai_next != NULL) { 290 debug("%s: getaddrinfo %.100s returned multiple addresses", 291 __func__, name); 292 goto fail; 293 } 294 if ((gaierr = getnameinfo(res->ai_addr, res->ai_addrlen, 295 addr, sizeof(addr), NULL, 0, NI_NUMERICHOST)) != 0) { 296 debug("%s: Could not format address for name %.100s: %s", 297 __func__, name, ssh_gai_strerror(gaierr)); 298 goto fail; 299 } 300 if (strlcpy(caddr, addr, clen) >= clen) { 301 error("%s: host \"%s\" addr \"%s\" too long (max %lu)", 302 __func__, name, addr, (u_long)clen); 303 if (clen > 0) 304 *caddr = '\0'; 305 fail: 306 freeaddrinfo(res); 307 return NULL; 308 } 309 return res; 310 } 311 312 /* 313 * Check whether the cname is a permitted replacement for the hostname 314 * and perform the replacement if it is. 315 * NB. this function must operate with a options having undefined members. 316 */ 317 static int 318 check_follow_cname(int direct, char **namep, const char *cname) 319 { 320 int i; 321 struct allowed_cname *rule; 322 323 if (*cname == '\0' || options.num_permitted_cnames == 0 || 324 strcmp(*namep, cname) == 0) 325 return 0; 326 if (options.canonicalize_hostname == SSH_CANONICALISE_NO) 327 return 0; 328 /* 329 * Don't attempt to canonicalize names that will be interpreted by 330 * a proxy or jump host unless the user specifically requests so. 331 */ 332 if (!direct && 333 options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS) 334 return 0; 335 debug3("%s: check \"%s\" CNAME \"%s\"", __func__, *namep, cname); 336 for (i = 0; i < options.num_permitted_cnames; i++) { 337 rule = options.permitted_cnames + i; 338 if (match_pattern_list(*namep, rule->source_list, 1) != 1 || 339 match_pattern_list(cname, rule->target_list, 1) != 1) 340 continue; 341 verbose("Canonicalized DNS aliased hostname " 342 "\"%s\" => \"%s\"", *namep, cname); 343 free(*namep); 344 *namep = xstrdup(cname); 345 return 1; 346 } 347 return 0; 348 } 349 350 /* 351 * Attempt to resolve the supplied hostname after applying the user's 352 * canonicalization rules. Returns the address list for the host or NULL 353 * if no name was found after canonicalization. 354 * NB. this function must operate with a options having undefined members. 355 */ 356 static struct addrinfo * 357 resolve_canonicalize(char **hostp, int port) 358 { 359 int i, direct, ndots; 360 char *cp, *fullhost, newname[NI_MAXHOST]; 361 struct addrinfo *addrs; 362 363 if (options.canonicalize_hostname == SSH_CANONICALISE_NO) 364 return NULL; 365 366 /* 367 * Don't attempt to canonicalize names that will be interpreted by 368 * a proxy unless the user specifically requests so. 369 */ 370 direct = option_clear_or_none(options.proxy_command) && 371 options.jump_host == NULL; 372 if (!direct && 373 options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS) 374 return NULL; 375 376 /* Try numeric hostnames first */ 377 if ((addrs = resolve_addr(*hostp, port, 378 newname, sizeof(newname))) != NULL) { 379 debug2("%s: hostname %.100s is address", __func__, *hostp); 380 if (strcasecmp(*hostp, newname) != 0) { 381 debug2("%s: canonicalised address \"%s\" => \"%s\"", 382 __func__, *hostp, newname); 383 free(*hostp); 384 *hostp = xstrdup(newname); 385 } 386 return addrs; 387 } 388 389 /* If domain name is anchored, then resolve it now */ 390 if ((*hostp)[strlen(*hostp) - 1] == '.') { 391 debug3("%s: name is fully qualified", __func__); 392 fullhost = xstrdup(*hostp); 393 if ((addrs = resolve_host(fullhost, port, 0, 394 newname, sizeof(newname))) != NULL) 395 goto found; 396 free(fullhost); 397 goto notfound; 398 } 399 400 /* Don't apply canonicalization to sufficiently-qualified hostnames */ 401 ndots = 0; 402 for (cp = *hostp; *cp != '\0'; cp++) { 403 if (*cp == '.') 404 ndots++; 405 } 406 if (ndots > options.canonicalize_max_dots) { 407 debug3("%s: not canonicalizing hostname \"%s\" (max dots %d)", 408 __func__, *hostp, options.canonicalize_max_dots); 409 return NULL; 410 } 411 /* Attempt each supplied suffix */ 412 for (i = 0; i < options.num_canonical_domains; i++) { 413 *newname = '\0'; 414 xasprintf(&fullhost, "%s.%s.", *hostp, 415 options.canonical_domains[i]); 416 debug3("%s: attempting \"%s\" => \"%s\"", __func__, 417 *hostp, fullhost); 418 if ((addrs = resolve_host(fullhost, port, 0, 419 newname, sizeof(newname))) == NULL) { 420 free(fullhost); 421 continue; 422 } 423 found: 424 /* Remove trailing '.' */ 425 fullhost[strlen(fullhost) - 1] = '\0'; 426 /* Follow CNAME if requested */ 427 if (!check_follow_cname(direct, &fullhost, newname)) { 428 debug("Canonicalized hostname \"%s\" => \"%s\"", 429 *hostp, fullhost); 430 } 431 free(*hostp); 432 *hostp = fullhost; 433 return addrs; 434 } 435 notfound: 436 if (!options.canonicalize_fallback_local) 437 fatal("%s: Could not resolve host \"%s\"", __progname, *hostp); 438 debug2("%s: host %s not found in any suffix", __func__, *hostp); 439 return NULL; 440 } 441 442 /* 443 * Read per-user configuration file. Ignore the system wide config 444 * file if the user specifies a config file on the command line. 445 */ 446 static void 447 process_config_files(const char *host_name, struct passwd *pw, int post_canon) 448 { 449 char buf[PATH_MAX]; 450 int r; 451 452 if (config != NULL) { 453 if (strcasecmp(config, "none") != 0 && 454 !read_config_file(config, pw, host, host_name, &options, 455 SSHCONF_USERCONF | (post_canon ? SSHCONF_POSTCANON : 0))) 456 fatal("Can't open user config file %.100s: " 457 "%.100s", config, strerror(errno)); 458 } else { 459 r = snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir, 460 _PATH_SSH_USER_CONFFILE); 461 if (r > 0 && (size_t)r < sizeof(buf)) 462 (void)read_config_file(buf, pw, host, host_name, 463 &options, SSHCONF_CHECKPERM | SSHCONF_USERCONF | 464 (post_canon ? SSHCONF_POSTCANON : 0)); 465 466 /* Read systemwide configuration file after user config. */ 467 (void)read_config_file(_PATH_HOST_CONFIG_FILE, pw, 468 host, host_name, &options, 469 post_canon ? SSHCONF_POSTCANON : 0); 470 } 471 } 472 473 /* Rewrite the port number in an addrinfo list of addresses */ 474 static void 475 set_addrinfo_port(struct addrinfo *addrs, int port) 476 { 477 struct addrinfo *addr; 478 479 for (addr = addrs; addr != NULL; addr = addr->ai_next) { 480 switch (addr->ai_family) { 481 case AF_INET: 482 ((struct sockaddr_in *)addr->ai_addr)-> 483 sin_port = htons(port); 484 break; 485 case AF_INET6: 486 ((struct sockaddr_in6 *)addr->ai_addr)-> 487 sin6_port = htons(port); 488 break; 489 } 490 } 491 } 492 493 /* 494 * Main program for the ssh client. 495 */ 496 int 497 main(int ac, char **av) 498 { 499 struct ssh *ssh = NULL; 500 int i, r, opt, exit_status, use_syslog, direct, timeout_ms; 501 int config_test = 0, opt_terminated = 0; 502 char *p, *cp, *line, *argv0, buf[PATH_MAX], *logfile; 503 char cname[NI_MAXHOST]; 504 struct stat st; 505 struct passwd *pw; 506 extern int optind, optreset; 507 extern char *optarg; 508 struct Forward fwd; 509 struct addrinfo *addrs = NULL; 510 struct ssh_digest_ctx *md; 511 u_char conn_hash[SSH_DIGEST_MAX_LENGTH]; 512 513 ssh_malloc_init(); /* must be called before any mallocs */ 514 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ 515 sanitise_stdfd(); 516 517 /* 518 * Discard other fds that are hanging around. These can cause problem 519 * with backgrounded ssh processes started by ControlPersist. 520 */ 521 closefrom(STDERR_FILENO + 1); 522 523 /* 524 * Save the original real uid. It will be needed later (uid-swapping 525 * may clobber the real uid). 526 */ 527 original_real_uid = getuid(); 528 original_effective_uid = geteuid(); 529 530 /* 531 * Use uid-swapping to give up root privileges for the duration of 532 * option processing. We will re-instantiate the rights when we are 533 * ready to create the privileged port, and will permanently drop 534 * them when the port has been created (actually, when the connection 535 * has been made, as we may need to create the port several times). 536 */ 537 PRIV_END; 538 539 /* If we are installed setuid root be careful to not drop core. */ 540 if (original_real_uid != original_effective_uid) { 541 struct rlimit rlim; 542 rlim.rlim_cur = rlim.rlim_max = 0; 543 if (setrlimit(RLIMIT_CORE, &rlim) < 0) 544 fatal("setrlimit failed: %.100s", strerror(errno)); 545 } 546 /* Get user data. */ 547 pw = getpwuid(original_real_uid); 548 if (!pw) { 549 logit("No user exists for uid %lu", (u_long)original_real_uid); 550 exit(255); 551 } 552 /* Take a copy of the returned structure. */ 553 pw = pwcopy(pw); 554 555 /* 556 * Set our umask to something reasonable, as some files are created 557 * with the default umask. This will make them world-readable but 558 * writable only by the owner, which is ok for all files for which we 559 * don't set the modes explicitly. 560 */ 561 umask(022); 562 563 setlocale(LC_CTYPE, ""); 564 565 /* 566 * Initialize option structure to indicate that no values have been 567 * set. 568 */ 569 initialize_options(&options); 570 571 /* 572 * Prepare main ssh transport/connection structures 573 */ 574 if ((ssh = ssh_alloc_session_state()) == NULL) 575 fatal("Couldn't allocate session state"); 576 channel_init_channels(ssh); 577 active_state = ssh; /* XXX legacy API compat */ 578 579 /* Parse command-line arguments. */ 580 host = NULL; 581 use_syslog = 0; 582 logfile = NULL; 583 argv0 = av[0]; 584 585 again: 586 while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx" 587 "ACD:E:F:GI:J:KL:MNO:PQ:R:S:TVw:W:XYy")) != -1) { 588 switch (opt) { 589 case '1': 590 fatal("SSH protocol v.1 is no longer supported"); 591 break; 592 case '2': 593 /* Ignored */ 594 break; 595 case '4': 596 options.address_family = AF_INET; 597 break; 598 case '6': 599 options.address_family = AF_INET6; 600 break; 601 case 'n': 602 stdin_null_flag = 1; 603 break; 604 case 'f': 605 fork_after_authentication_flag = 1; 606 stdin_null_flag = 1; 607 break; 608 case 'x': 609 options.forward_x11 = 0; 610 break; 611 case 'X': 612 options.forward_x11 = 1; 613 break; 614 case 'y': 615 use_syslog = 1; 616 break; 617 case 'E': 618 logfile = optarg; 619 break; 620 case 'G': 621 config_test = 1; 622 break; 623 case 'Y': 624 options.forward_x11 = 1; 625 options.forward_x11_trusted = 1; 626 break; 627 case 'g': 628 options.fwd_opts.gateway_ports = 1; 629 break; 630 case 'O': 631 if (options.stdio_forward_host != NULL) 632 fatal("Cannot specify multiplexing " 633 "command with -W"); 634 else if (muxclient_command != 0) 635 fatal("Multiplexing command already specified"); 636 if (strcmp(optarg, "check") == 0) 637 muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK; 638 else if (strcmp(optarg, "forward") == 0) 639 muxclient_command = SSHMUX_COMMAND_FORWARD; 640 else if (strcmp(optarg, "exit") == 0) 641 muxclient_command = SSHMUX_COMMAND_TERMINATE; 642 else if (strcmp(optarg, "stop") == 0) 643 muxclient_command = SSHMUX_COMMAND_STOP; 644 else if (strcmp(optarg, "cancel") == 0) 645 muxclient_command = SSHMUX_COMMAND_CANCEL_FWD; 646 else if (strcmp(optarg, "proxy") == 0) 647 muxclient_command = SSHMUX_COMMAND_PROXY; 648 else 649 fatal("Invalid multiplex command."); 650 break; 651 case 'P': /* deprecated */ 652 options.use_privileged_port = 0; 653 break; 654 case 'Q': 655 cp = NULL; 656 if (strcmp(optarg, "cipher") == 0) 657 cp = cipher_alg_list('\n', 0); 658 else if (strcmp(optarg, "cipher-auth") == 0) 659 cp = cipher_alg_list('\n', 1); 660 else if (strcmp(optarg, "mac") == 0) 661 cp = mac_alg_list('\n'); 662 else if (strcmp(optarg, "kex") == 0) 663 cp = kex_alg_list('\n'); 664 else if (strcmp(optarg, "key") == 0) 665 cp = sshkey_alg_list(0, 0, 0, '\n'); 666 else if (strcmp(optarg, "key-cert") == 0) 667 cp = sshkey_alg_list(1, 0, 0, '\n'); 668 else if (strcmp(optarg, "key-plain") == 0) 669 cp = sshkey_alg_list(0, 1, 0, '\n'); 670 else if (strcmp(optarg, "protocol-version") == 0) { 671 cp = xstrdup("2"); 672 } 673 if (cp == NULL) 674 fatal("Unsupported query \"%s\"", optarg); 675 printf("%s\n", cp); 676 free(cp); 677 exit(0); 678 break; 679 case 'a': 680 options.forward_agent = 0; 681 break; 682 case 'A': 683 options.forward_agent = 1; 684 break; 685 case 'k': 686 options.gss_deleg_creds = 0; 687 break; 688 case 'K': 689 options.gss_authentication = 1; 690 options.gss_deleg_creds = 1; 691 break; 692 case 'i': 693 p = tilde_expand_filename(optarg, original_real_uid); 694 if (stat(p, &st) < 0) 695 fprintf(stderr, "Warning: Identity file %s " 696 "not accessible: %s.\n", p, 697 strerror(errno)); 698 else 699 add_identity_file(&options, NULL, p, 1); 700 free(p); 701 break; 702 case 'I': 703 #ifdef ENABLE_PKCS11 704 free(options.pkcs11_provider); 705 options.pkcs11_provider = xstrdup(optarg); 706 #else 707 fprintf(stderr, "no support for PKCS#11.\n"); 708 #endif 709 break; 710 case 'J': 711 if (options.jump_host != NULL) 712 fatal("Only a single -J option permitted"); 713 if (options.proxy_command != NULL) 714 fatal("Cannot specify -J with ProxyCommand"); 715 if (parse_jump(optarg, &options, 1) == -1) 716 fatal("Invalid -J argument"); 717 options.proxy_command = xstrdup("none"); 718 break; 719 case 't': 720 if (options.request_tty == REQUEST_TTY_YES) 721 options.request_tty = REQUEST_TTY_FORCE; 722 else 723 options.request_tty = REQUEST_TTY_YES; 724 break; 725 case 'v': 726 if (debug_flag == 0) { 727 debug_flag = 1; 728 options.log_level = SYSLOG_LEVEL_DEBUG1; 729 } else { 730 if (options.log_level < SYSLOG_LEVEL_DEBUG3) { 731 debug_flag++; 732 options.log_level++; 733 } 734 } 735 break; 736 case 'V': 737 fprintf(stderr, "%s, %s\n", 738 SSH_VERSION, 739 #ifdef WITH_OPENSSL 740 SSLeay_version(SSLEAY_VERSION) 741 #else 742 "without OpenSSL" 743 #endif 744 ); 745 if (opt == 'V') 746 exit(0); 747 break; 748 case 'w': 749 if (options.tun_open == -1) 750 options.tun_open = SSH_TUNMODE_DEFAULT; 751 options.tun_local = a2tun(optarg, &options.tun_remote); 752 if (options.tun_local == SSH_TUNID_ERR) { 753 fprintf(stderr, 754 "Bad tun device '%s'\n", optarg); 755 exit(255); 756 } 757 break; 758 case 'W': 759 if (options.stdio_forward_host != NULL) 760 fatal("stdio forward already specified"); 761 if (muxclient_command != 0) 762 fatal("Cannot specify stdio forward with -O"); 763 if (parse_forward(&fwd, optarg, 1, 0)) { 764 options.stdio_forward_host = fwd.listen_host; 765 options.stdio_forward_port = fwd.listen_port; 766 free(fwd.connect_host); 767 } else { 768 fprintf(stderr, 769 "Bad stdio forwarding specification '%s'\n", 770 optarg); 771 exit(255); 772 } 773 options.request_tty = REQUEST_TTY_NO; 774 no_shell_flag = 1; 775 break; 776 case 'q': 777 options.log_level = SYSLOG_LEVEL_QUIET; 778 break; 779 case 'e': 780 if (optarg[0] == '^' && optarg[2] == 0 && 781 (u_char) optarg[1] >= 64 && 782 (u_char) optarg[1] < 128) 783 options.escape_char = (u_char) optarg[1] & 31; 784 else if (strlen(optarg) == 1) 785 options.escape_char = (u_char) optarg[0]; 786 else if (strcmp(optarg, "none") == 0) 787 options.escape_char = SSH_ESCAPECHAR_NONE; 788 else { 789 fprintf(stderr, "Bad escape character '%s'.\n", 790 optarg); 791 exit(255); 792 } 793 break; 794 case 'c': 795 if (!ciphers_valid(*optarg == '+' ? 796 optarg + 1 : optarg)) { 797 fprintf(stderr, "Unknown cipher type '%s'\n", 798 optarg); 799 exit(255); 800 } 801 free(options.ciphers); 802 options.ciphers = xstrdup(optarg); 803 break; 804 case 'm': 805 if (mac_valid(optarg)) { 806 free(options.macs); 807 options.macs = xstrdup(optarg); 808 } else { 809 fprintf(stderr, "Unknown mac type '%s'\n", 810 optarg); 811 exit(255); 812 } 813 break; 814 case 'M': 815 if (options.control_master == SSHCTL_MASTER_YES) 816 options.control_master = SSHCTL_MASTER_ASK; 817 else 818 options.control_master = SSHCTL_MASTER_YES; 819 break; 820 case 'p': 821 if (options.port == -1) { 822 options.port = a2port(optarg); 823 if (options.port <= 0) { 824 fprintf(stderr, "Bad port '%s'\n", 825 optarg); 826 exit(255); 827 } 828 } 829 break; 830 case 'l': 831 if (options.user == NULL) 832 options.user = optarg; 833 break; 834 835 case 'L': 836 if (parse_forward(&fwd, optarg, 0, 0)) 837 add_local_forward(&options, &fwd); 838 else { 839 fprintf(stderr, 840 "Bad local forwarding specification '%s'\n", 841 optarg); 842 exit(255); 843 } 844 break; 845 846 case 'R': 847 if (parse_forward(&fwd, optarg, 0, 1) || 848 parse_forward(&fwd, optarg, 1, 1)) { 849 add_remote_forward(&options, &fwd); 850 } else { 851 fprintf(stderr, 852 "Bad remote forwarding specification " 853 "'%s'\n", optarg); 854 exit(255); 855 } 856 break; 857 858 case 'D': 859 if (parse_forward(&fwd, optarg, 1, 0)) { 860 add_local_forward(&options, &fwd); 861 } else { 862 fprintf(stderr, 863 "Bad dynamic forwarding specification " 864 "'%s'\n", optarg); 865 exit(255); 866 } 867 break; 868 869 case 'C': 870 options.compression = 1; 871 break; 872 case 'N': 873 no_shell_flag = 1; 874 options.request_tty = REQUEST_TTY_NO; 875 break; 876 case 'T': 877 options.request_tty = REQUEST_TTY_NO; 878 break; 879 case 'o': 880 line = xstrdup(optarg); 881 if (process_config_line(&options, pw, 882 host ? host : "", host ? host : "", line, 883 "command-line", 0, NULL, SSHCONF_USERCONF) != 0) 884 exit(255); 885 free(line); 886 break; 887 case 's': 888 subsystem_flag = 1; 889 break; 890 case 'S': 891 free(options.control_path); 892 options.control_path = xstrdup(optarg); 893 break; 894 case 'b': 895 options.bind_address = optarg; 896 break; 897 case 'F': 898 config = optarg; 899 break; 900 default: 901 usage(); 902 } 903 } 904 905 if (optind > 1 && strcmp(av[optind - 1], "--") == 0) 906 opt_terminated = 1; 907 908 ac -= optind; 909 av += optind; 910 911 if (ac > 0 && !host) { 912 int tport; 913 char *tuser; 914 switch (parse_ssh_uri(*av, &tuser, &host, &tport)) { 915 case -1: 916 usage(); 917 break; 918 case 0: 919 if (options.user == NULL) { 920 options.user = tuser; 921 tuser = NULL; 922 } 923 free(tuser); 924 if (options.port == -1 && tport != -1) 925 options.port = tport; 926 break; 927 default: 928 p = xstrdup(*av); 929 cp = strrchr(p, '@'); 930 if (cp != NULL) { 931 if (cp == p) 932 usage(); 933 if (options.user == NULL) { 934 options.user = p; 935 p = NULL; 936 } 937 *cp++ = '\0'; 938 host = xstrdup(cp); 939 free(p); 940 } else 941 host = p; 942 break; 943 } 944 if (ac > 1 && !opt_terminated) { 945 optind = optreset = 1; 946 goto again; 947 } 948 ac--, av++; 949 } 950 951 /* Check that we got a host name. */ 952 if (!host) 953 usage(); 954 955 host_arg = xstrdup(host); 956 957 #ifdef WITH_OPENSSL 958 OpenSSL_add_all_algorithms(); 959 ERR_load_crypto_strings(); 960 #endif 961 962 /* Initialize the command to execute on remote host. */ 963 buffer_init(&command); 964 965 /* 966 * Save the command to execute on the remote host in a buffer. There 967 * is no limit on the length of the command, except by the maximum 968 * packet size. Also sets the tty flag if there is no command. 969 */ 970 if (!ac) { 971 /* No command specified - execute shell on a tty. */ 972 if (subsystem_flag) { 973 fprintf(stderr, 974 "You must specify a subsystem to invoke.\n"); 975 usage(); 976 } 977 } else { 978 /* A command has been specified. Store it into the buffer. */ 979 for (i = 0; i < ac; i++) { 980 if (i) 981 buffer_append(&command, " ", 1); 982 buffer_append(&command, av[i], strlen(av[i])); 983 } 984 } 985 986 /* 987 * Initialize "log" output. Since we are the client all output 988 * goes to stderr unless otherwise specified by -y or -E. 989 */ 990 if (use_syslog && logfile != NULL) 991 fatal("Can't specify both -y and -E"); 992 if (logfile != NULL) 993 log_redirect_stderr_to(logfile); 994 log_init(argv0, 995 options.log_level == SYSLOG_LEVEL_NOT_SET ? 996 SYSLOG_LEVEL_INFO : options.log_level, 997 options.log_facility == SYSLOG_FACILITY_NOT_SET ? 998 SYSLOG_FACILITY_USER : options.log_facility, 999 !use_syslog); 1000 1001 if (debug_flag) 1002 logit("%s, %s", SSH_VERSION, 1003 #ifdef WITH_OPENSSL 1004 SSLeay_version(SSLEAY_VERSION) 1005 #else 1006 "without OpenSSL" 1007 #endif 1008 ); 1009 1010 /* Parse the configuration files */ 1011 process_config_files(host_arg, pw, 0); 1012 1013 /* Hostname canonicalisation needs a few options filled. */ 1014 fill_default_options_for_canonicalization(&options); 1015 1016 /* If the user has replaced the hostname then take it into use now */ 1017 if (options.hostname != NULL) { 1018 /* NB. Please keep in sync with readconf.c:match_cfg_line() */ 1019 cp = percent_expand(options.hostname, 1020 "h", host, (char *)NULL); 1021 free(host); 1022 host = cp; 1023 free(options.hostname); 1024 options.hostname = xstrdup(host); 1025 } 1026 1027 /* If canonicalization requested then try to apply it */ 1028 lowercase(host); 1029 if (options.canonicalize_hostname != SSH_CANONICALISE_NO) 1030 addrs = resolve_canonicalize(&host, options.port); 1031 1032 /* 1033 * If CanonicalizePermittedCNAMEs have been specified but 1034 * other canonicalization did not happen (by not being requested 1035 * or by failing with fallback) then the hostname may still be changed 1036 * as a result of CNAME following. 1037 * 1038 * Try to resolve the bare hostname name using the system resolver's 1039 * usual search rules and then apply the CNAME follow rules. 1040 * 1041 * Skip the lookup if a ProxyCommand is being used unless the user 1042 * has specifically requested canonicalisation for this case via 1043 * CanonicalizeHostname=always 1044 */ 1045 direct = option_clear_or_none(options.proxy_command) && 1046 options.jump_host == NULL; 1047 if (addrs == NULL && options.num_permitted_cnames != 0 && (direct || 1048 options.canonicalize_hostname == SSH_CANONICALISE_ALWAYS)) { 1049 if ((addrs = resolve_host(host, options.port, 1050 option_clear_or_none(options.proxy_command), 1051 cname, sizeof(cname))) == NULL) { 1052 /* Don't fatal proxied host names not in the DNS */ 1053 if (option_clear_or_none(options.proxy_command)) 1054 cleanup_exit(255); /* logged in resolve_host */ 1055 } else 1056 check_follow_cname(direct, &host, cname); 1057 } 1058 1059 /* 1060 * If canonicalisation is enabled then re-parse the configuration 1061 * files as new stanzas may match. 1062 */ 1063 if (options.canonicalize_hostname != 0) { 1064 debug("Re-reading configuration after hostname " 1065 "canonicalisation"); 1066 free(options.hostname); 1067 options.hostname = xstrdup(host); 1068 process_config_files(host_arg, pw, 1); 1069 /* 1070 * Address resolution happens early with canonicalisation 1071 * enabled and the port number may have changed since, so 1072 * reset it in address list 1073 */ 1074 if (addrs != NULL && options.port > 0) 1075 set_addrinfo_port(addrs, options.port); 1076 } 1077 1078 /* Fill configuration defaults. */ 1079 fill_default_options(&options); 1080 1081 /* 1082 * If ProxyJump option specified, then construct a ProxyCommand now. 1083 */ 1084 if (options.jump_host != NULL) { 1085 char port_s[8]; 1086 1087 /* Consistency check */ 1088 if (options.proxy_command != NULL) 1089 fatal("inconsistent options: ProxyCommand+ProxyJump"); 1090 /* Never use FD passing for ProxyJump */ 1091 options.proxy_use_fdpass = 0; 1092 snprintf(port_s, sizeof(port_s), "%d", options.jump_port); 1093 xasprintf(&options.proxy_command, 1094 "ssh%s%s%s%s%s%s%s%s%s%.*s -W '[%%h]:%%p' %s", 1095 /* Optional "-l user" argument if jump_user set */ 1096 options.jump_user == NULL ? "" : " -l ", 1097 options.jump_user == NULL ? "" : options.jump_user, 1098 /* Optional "-p port" argument if jump_port set */ 1099 options.jump_port <= 0 ? "" : " -p ", 1100 options.jump_port <= 0 ? "" : port_s, 1101 /* Optional additional jump hosts ",..." */ 1102 options.jump_extra == NULL ? "" : " -J ", 1103 options.jump_extra == NULL ? "" : options.jump_extra, 1104 /* Optional "-F" argumment if -F specified */ 1105 config == NULL ? "" : " -F ", 1106 config == NULL ? "" : config, 1107 /* Optional "-v" arguments if -v set */ 1108 debug_flag ? " -" : "", 1109 debug_flag, "vvv", 1110 /* Mandatory hostname */ 1111 options.jump_host); 1112 debug("Setting implicit ProxyCommand from ProxyJump: %s", 1113 options.proxy_command); 1114 } 1115 1116 if (options.port == 0) 1117 options.port = default_ssh_port(); 1118 channel_set_af(ssh, options.address_family); 1119 1120 /* Tidy and check options */ 1121 if (options.host_key_alias != NULL) 1122 lowercase(options.host_key_alias); 1123 if (options.proxy_command != NULL && 1124 strcmp(options.proxy_command, "-") == 0 && 1125 options.proxy_use_fdpass) 1126 fatal("ProxyCommand=- and ProxyUseFDPass are incompatible"); 1127 if (options.control_persist && 1128 options.update_hostkeys == SSH_UPDATE_HOSTKEYS_ASK) { 1129 debug("UpdateHostKeys=ask is incompatible with ControlPersist; " 1130 "disabling"); 1131 options.update_hostkeys = 0; 1132 } 1133 if (options.connection_attempts <= 0) 1134 fatal("Invalid number of ConnectionAttempts"); 1135 1136 if (original_effective_uid != 0) 1137 options.use_privileged_port = 0; 1138 1139 if (buffer_len(&command) != 0 && options.remote_command != NULL) 1140 fatal("Cannot execute command-line and remote command."); 1141 1142 /* Cannot fork to background if no command. */ 1143 if (fork_after_authentication_flag && buffer_len(&command) == 0 && 1144 options.remote_command == NULL && !no_shell_flag) 1145 fatal("Cannot fork into background without a command " 1146 "to execute."); 1147 1148 /* reinit */ 1149 log_init(argv0, options.log_level, options.log_facility, !use_syslog); 1150 1151 if (options.request_tty == REQUEST_TTY_YES || 1152 options.request_tty == REQUEST_TTY_FORCE) 1153 tty_flag = 1; 1154 1155 /* Allocate a tty by default if no command specified. */ 1156 if (buffer_len(&command) == 0 && options.remote_command == NULL) 1157 tty_flag = options.request_tty != REQUEST_TTY_NO; 1158 1159 /* Force no tty */ 1160 if (options.request_tty == REQUEST_TTY_NO || 1161 (muxclient_command && muxclient_command != SSHMUX_COMMAND_PROXY)) 1162 tty_flag = 0; 1163 /* Do not allocate a tty if stdin is not a tty. */ 1164 if ((!isatty(fileno(stdin)) || stdin_null_flag) && 1165 options.request_tty != REQUEST_TTY_FORCE) { 1166 if (tty_flag) 1167 logit("Pseudo-terminal will not be allocated because " 1168 "stdin is not a terminal."); 1169 tty_flag = 0; 1170 } 1171 1172 if (options.user == NULL) 1173 options.user = xstrdup(pw->pw_name); 1174 1175 /* Set up strings used to percent_expand() arguments */ 1176 if (gethostname(thishost, sizeof(thishost)) == -1) 1177 fatal("gethostname: %s", strerror(errno)); 1178 strlcpy(shorthost, thishost, sizeof(shorthost)); 1179 shorthost[strcspn(thishost, ".")] = '\0'; 1180 snprintf(portstr, sizeof(portstr), "%d", options.port); 1181 snprintf(uidstr, sizeof(uidstr), "%d", pw->pw_uid); 1182 1183 if ((md = ssh_digest_start(SSH_DIGEST_SHA1)) == NULL || 1184 ssh_digest_update(md, thishost, strlen(thishost)) < 0 || 1185 ssh_digest_update(md, host, strlen(host)) < 0 || 1186 ssh_digest_update(md, portstr, strlen(portstr)) < 0 || 1187 ssh_digest_update(md, options.user, strlen(options.user)) < 0 || 1188 ssh_digest_final(md, conn_hash, sizeof(conn_hash)) < 0) 1189 fatal("%s: mux digest failed", __func__); 1190 ssh_digest_free(md); 1191 conn_hash_hex = tohex(conn_hash, ssh_digest_bytes(SSH_DIGEST_SHA1)); 1192 1193 /* 1194 * Expand tokens in arguments. NB. LocalCommand is expanded later, 1195 * after port-forwarding is set up, so it may pick up any local 1196 * tunnel interface name allocated. 1197 */ 1198 if (options.remote_command != NULL) { 1199 debug3("expanding RemoteCommand: %s", options.remote_command); 1200 cp = options.remote_command; 1201 options.remote_command = percent_expand(cp, 1202 "C", conn_hash_hex, 1203 "L", shorthost, 1204 "d", pw->pw_dir, 1205 "h", host, 1206 "l", thishost, 1207 "n", host_arg, 1208 "p", portstr, 1209 "r", options.user, 1210 "u", pw->pw_name, 1211 (char *)NULL); 1212 debug3("expanded RemoteCommand: %s", options.remote_command); 1213 free(cp); 1214 buffer_append(&command, options.remote_command, 1215 strlen(options.remote_command)); 1216 } 1217 1218 if (options.control_path != NULL) { 1219 cp = tilde_expand_filename(options.control_path, 1220 original_real_uid); 1221 free(options.control_path); 1222 options.control_path = percent_expand(cp, 1223 "C", conn_hash_hex, 1224 "L", shorthost, 1225 "h", host, 1226 "l", thishost, 1227 "n", host_arg, 1228 "p", portstr, 1229 "r", options.user, 1230 "u", pw->pw_name, 1231 "i", uidstr, 1232 (char *)NULL); 1233 free(cp); 1234 } 1235 free(conn_hash_hex); 1236 1237 if (config_test) { 1238 dump_client_config(&options, host); 1239 exit(0); 1240 } 1241 1242 if (muxclient_command != 0 && options.control_path == NULL) 1243 fatal("No ControlPath specified for \"-O\" command"); 1244 if (options.control_path != NULL) { 1245 int sock; 1246 if ((sock = muxclient(options.control_path)) >= 0) { 1247 ssh_packet_set_connection(ssh, sock, sock); 1248 packet_set_mux(); 1249 goto skip_connect; 1250 } 1251 } 1252 1253 /* 1254 * If hostname canonicalisation was not enabled, then we may not 1255 * have yet resolved the hostname. Do so now. 1256 */ 1257 if (addrs == NULL && options.proxy_command == NULL) { 1258 debug2("resolving \"%s\" port %d", host, options.port); 1259 if ((addrs = resolve_host(host, options.port, 1, 1260 cname, sizeof(cname))) == NULL) 1261 cleanup_exit(255); /* resolve_host logs the error */ 1262 } 1263 1264 timeout_ms = options.connection_timeout * 1000; 1265 1266 /* Open a connection to the remote host. */ 1267 if (ssh_connect(ssh, host, addrs, &hostaddr, options.port, 1268 options.address_family, options.connection_attempts, 1269 &timeout_ms, options.tcp_keep_alive, 1270 options.use_privileged_port) != 0) 1271 exit(255); 1272 1273 if (addrs != NULL) 1274 freeaddrinfo(addrs); 1275 1276 packet_set_timeout(options.server_alive_interval, 1277 options.server_alive_count_max); 1278 1279 ssh = active_state; /* XXX */ 1280 1281 if (timeout_ms > 0) 1282 debug3("timeout: %d ms remain after connect", timeout_ms); 1283 1284 /* 1285 * If we successfully made the connection, load the host private key 1286 * in case we will need it later for combined rsa-rhosts 1287 * authentication. This must be done before releasing extra 1288 * privileges, because the file is only readable by root. 1289 * If we cannot access the private keys, load the public keys 1290 * instead and try to execute the ssh-keysign helper instead. 1291 */ 1292 sensitive_data.nkeys = 0; 1293 sensitive_data.keys = NULL; 1294 sensitive_data.external_keysign = 0; 1295 if (options.hostbased_authentication) { 1296 sensitive_data.nkeys = 9; 1297 sensitive_data.keys = xcalloc(sensitive_data.nkeys, 1298 sizeof(struct sshkey)); /* XXX */ 1299 1300 PRIV_START; 1301 sensitive_data.keys[1] = key_load_private_cert(KEY_ECDSA, 1302 _PATH_HOST_ECDSA_KEY_FILE, "", NULL); 1303 sensitive_data.keys[2] = key_load_private_cert(KEY_ED25519, 1304 _PATH_HOST_ED25519_KEY_FILE, "", NULL); 1305 sensitive_data.keys[3] = key_load_private_cert(KEY_RSA, 1306 _PATH_HOST_RSA_KEY_FILE, "", NULL); 1307 sensitive_data.keys[4] = key_load_private_cert(KEY_DSA, 1308 _PATH_HOST_DSA_KEY_FILE, "", NULL); 1309 sensitive_data.keys[5] = key_load_private_type(KEY_ECDSA, 1310 _PATH_HOST_ECDSA_KEY_FILE, "", NULL, NULL); 1311 sensitive_data.keys[6] = key_load_private_type(KEY_ED25519, 1312 _PATH_HOST_ED25519_KEY_FILE, "", NULL, NULL); 1313 sensitive_data.keys[7] = key_load_private_type(KEY_RSA, 1314 _PATH_HOST_RSA_KEY_FILE, "", NULL, NULL); 1315 sensitive_data.keys[8] = key_load_private_type(KEY_DSA, 1316 _PATH_HOST_DSA_KEY_FILE, "", NULL, NULL); 1317 PRIV_END; 1318 1319 if (options.hostbased_authentication == 1 && 1320 sensitive_data.keys[0] == NULL && 1321 sensitive_data.keys[5] == NULL && 1322 sensitive_data.keys[6] == NULL && 1323 sensitive_data.keys[7] == NULL && 1324 sensitive_data.keys[8] == NULL) { 1325 sensitive_data.keys[1] = key_load_cert( 1326 _PATH_HOST_ECDSA_KEY_FILE); 1327 sensitive_data.keys[2] = key_load_cert( 1328 _PATH_HOST_ED25519_KEY_FILE); 1329 sensitive_data.keys[3] = key_load_cert( 1330 _PATH_HOST_RSA_KEY_FILE); 1331 sensitive_data.keys[4] = key_load_cert( 1332 _PATH_HOST_DSA_KEY_FILE); 1333 sensitive_data.keys[5] = key_load_public( 1334 _PATH_HOST_ECDSA_KEY_FILE, NULL); 1335 sensitive_data.keys[6] = key_load_public( 1336 _PATH_HOST_ED25519_KEY_FILE, NULL); 1337 sensitive_data.keys[7] = key_load_public( 1338 _PATH_HOST_RSA_KEY_FILE, NULL); 1339 sensitive_data.keys[8] = key_load_public( 1340 _PATH_HOST_DSA_KEY_FILE, NULL); 1341 sensitive_data.external_keysign = 1; 1342 } 1343 } 1344 /* 1345 * Get rid of any extra privileges that we may have. We will no 1346 * longer need them. Also, extra privileges could make it very hard 1347 * to read identity files and other non-world-readable files from the 1348 * user's home directory if it happens to be on a NFS volume where 1349 * root is mapped to nobody. 1350 */ 1351 if (original_effective_uid == 0) { 1352 PRIV_START; 1353 permanently_set_uid(pw); 1354 } 1355 1356 /* 1357 * Now that we are back to our own permissions, create ~/.ssh 1358 * directory if it doesn't already exist. 1359 */ 1360 if (config == NULL) { 1361 r = snprintf(buf, sizeof buf, "%s%s%s", pw->pw_dir, 1362 strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR); 1363 if (r > 0 && (size_t)r < sizeof(buf) && stat(buf, &st) < 0) 1364 if (mkdir(buf, 0700) < 0) 1365 error("Could not create directory '%.200s'.", 1366 buf); 1367 } 1368 1369 /* load options.identity_files */ 1370 load_public_identity_files(pw); 1371 1372 /* optionally set the SSH_AUTHSOCKET_ENV_NAME varibale */ 1373 if (options.identity_agent && 1374 strcmp(options.identity_agent, SSH_AUTHSOCKET_ENV_NAME) != 0) { 1375 if (strcmp(options.identity_agent, "none") == 0) { 1376 unsetenv(SSH_AUTHSOCKET_ENV_NAME); 1377 } else { 1378 p = tilde_expand_filename(options.identity_agent, 1379 original_real_uid); 1380 cp = percent_expand(p, "d", pw->pw_dir, 1381 "u", pw->pw_name, "l", thishost, "h", host, 1382 "r", options.user, (char *)NULL); 1383 setenv(SSH_AUTHSOCKET_ENV_NAME, cp, 1); 1384 free(cp); 1385 free(p); 1386 } 1387 } 1388 1389 /* Expand ~ in known host file names. */ 1390 tilde_expand_paths(options.system_hostfiles, 1391 options.num_system_hostfiles); 1392 tilde_expand_paths(options.user_hostfiles, options.num_user_hostfiles); 1393 1394 signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */ 1395 signal(SIGCHLD, main_sigchld_handler); 1396 1397 /* Log into the remote system. Never returns if the login fails. */ 1398 ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr, 1399 options.port, pw, timeout_ms); 1400 1401 if (packet_connection_is_on_socket()) { 1402 verbose("Authenticated to %s ([%s]:%d).", host, 1403 ssh_remote_ipaddr(ssh), ssh_remote_port(ssh)); 1404 } else { 1405 verbose("Authenticated to %s (via proxy).", host); 1406 } 1407 1408 /* We no longer need the private host keys. Clear them now. */ 1409 if (sensitive_data.nkeys != 0) { 1410 for (i = 0; i < sensitive_data.nkeys; i++) { 1411 if (sensitive_data.keys[i] != NULL) { 1412 /* Destroys contents safely */ 1413 debug3("clear hostkey %d", i); 1414 key_free(sensitive_data.keys[i]); 1415 sensitive_data.keys[i] = NULL; 1416 } 1417 } 1418 free(sensitive_data.keys); 1419 } 1420 for (i = 0; i < options.num_identity_files; i++) { 1421 free(options.identity_files[i]); 1422 options.identity_files[i] = NULL; 1423 if (options.identity_keys[i]) { 1424 key_free(options.identity_keys[i]); 1425 options.identity_keys[i] = NULL; 1426 } 1427 } 1428 for (i = 0; i < options.num_certificate_files; i++) { 1429 free(options.certificate_files[i]); 1430 options.certificate_files[i] = NULL; 1431 } 1432 1433 skip_connect: 1434 exit_status = ssh_session2(ssh, pw); 1435 packet_close(); 1436 1437 if (options.control_path != NULL && muxserver_sock != -1) 1438 unlink(options.control_path); 1439 1440 /* Kill ProxyCommand if it is running. */ 1441 ssh_kill_proxy_command(); 1442 1443 return exit_status; 1444 } 1445 1446 static void 1447 control_persist_detach(void) 1448 { 1449 pid_t pid; 1450 int devnull, keep_stderr; 1451 1452 debug("%s: backgrounding master process", __func__); 1453 1454 /* 1455 * master (current process) into the background, and make the 1456 * foreground process a client of the backgrounded master. 1457 */ 1458 switch ((pid = fork())) { 1459 case -1: 1460 fatal("%s: fork: %s", __func__, strerror(errno)); 1461 case 0: 1462 /* Child: master process continues mainloop */ 1463 break; 1464 default: 1465 /* Parent: set up mux slave to connect to backgrounded master */ 1466 debug2("%s: background process is %ld", __func__, (long)pid); 1467 stdin_null_flag = ostdin_null_flag; 1468 options.request_tty = orequest_tty; 1469 tty_flag = otty_flag; 1470 close(muxserver_sock); 1471 muxserver_sock = -1; 1472 options.control_master = SSHCTL_MASTER_NO; 1473 muxclient(options.control_path); 1474 /* muxclient() doesn't return on success. */ 1475 fatal("Failed to connect to new control master"); 1476 } 1477 if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) { 1478 error("%s: open(\"/dev/null\"): %s", __func__, 1479 strerror(errno)); 1480 } else { 1481 keep_stderr = log_is_on_stderr() && debug_flag; 1482 if (dup2(devnull, STDIN_FILENO) == -1 || 1483 dup2(devnull, STDOUT_FILENO) == -1 || 1484 (!keep_stderr && dup2(devnull, STDERR_FILENO) == -1)) 1485 error("%s: dup2: %s", __func__, strerror(errno)); 1486 if (devnull > STDERR_FILENO) 1487 close(devnull); 1488 } 1489 daemon(1, 1); 1490 setproctitle("%s [mux]", options.control_path); 1491 } 1492 1493 /* Do fork() after authentication. Used by "ssh -f" */ 1494 static void 1495 fork_postauth(void) 1496 { 1497 if (need_controlpersist_detach) 1498 control_persist_detach(); 1499 debug("forking to background"); 1500 fork_after_authentication_flag = 0; 1501 if (daemon(1, 1) < 0) 1502 fatal("daemon() failed: %.200s", strerror(errno)); 1503 } 1504 1505 /* Callback for remote forward global requests */ 1506 static void 1507 ssh_confirm_remote_forward(struct ssh *ssh, int type, u_int32_t seq, void *ctxt) 1508 { 1509 struct Forward *rfwd = (struct Forward *)ctxt; 1510 1511 /* XXX verbose() on failure? */ 1512 debug("remote forward %s for: listen %s%s%d, connect %s:%d", 1513 type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure", 1514 rfwd->listen_path ? rfwd->listen_path : 1515 rfwd->listen_host ? rfwd->listen_host : "", 1516 (rfwd->listen_path || rfwd->listen_host) ? ":" : "", 1517 rfwd->listen_port, rfwd->connect_path ? rfwd->connect_path : 1518 rfwd->connect_host, rfwd->connect_port); 1519 if (rfwd->listen_path == NULL && rfwd->listen_port == 0) { 1520 if (type == SSH2_MSG_REQUEST_SUCCESS) { 1521 rfwd->allocated_port = packet_get_int(); 1522 logit("Allocated port %u for remote forward to %s:%d", 1523 rfwd->allocated_port, 1524 rfwd->connect_host, rfwd->connect_port); 1525 channel_update_permitted_opens(ssh, 1526 rfwd->handle, rfwd->allocated_port); 1527 } else { 1528 channel_update_permitted_opens(ssh, rfwd->handle, -1); 1529 } 1530 } 1531 1532 if (type == SSH2_MSG_REQUEST_FAILURE) { 1533 if (options.exit_on_forward_failure) { 1534 if (rfwd->listen_path != NULL) 1535 fatal("Error: remote port forwarding failed " 1536 "for listen path %s", rfwd->listen_path); 1537 else 1538 fatal("Error: remote port forwarding failed " 1539 "for listen port %d", rfwd->listen_port); 1540 } else { 1541 if (rfwd->listen_path != NULL) 1542 logit("Warning: remote port forwarding failed " 1543 "for listen path %s", rfwd->listen_path); 1544 else 1545 logit("Warning: remote port forwarding failed " 1546 "for listen port %d", rfwd->listen_port); 1547 } 1548 } 1549 if (++remote_forward_confirms_received == options.num_remote_forwards) { 1550 debug("All remote forwarding requests processed"); 1551 if (fork_after_authentication_flag) 1552 fork_postauth(); 1553 } 1554 } 1555 1556 static void 1557 client_cleanup_stdio_fwd(struct ssh *ssh, int id, void *arg) 1558 { 1559 debug("stdio forwarding: done"); 1560 cleanup_exit(0); 1561 } 1562 1563 static void 1564 ssh_stdio_confirm(struct ssh *ssh, int id, int success, void *arg) 1565 { 1566 if (!success) 1567 fatal("stdio forwarding failed"); 1568 } 1569 1570 static void 1571 ssh_init_stdio_forwarding(struct ssh *ssh) 1572 { 1573 Channel *c; 1574 int in, out; 1575 1576 if (options.stdio_forward_host == NULL) 1577 return; 1578 1579 debug3("%s: %s:%d", __func__, options.stdio_forward_host, 1580 options.stdio_forward_port); 1581 1582 if ((in = dup(STDIN_FILENO)) < 0 || 1583 (out = dup(STDOUT_FILENO)) < 0) 1584 fatal("channel_connect_stdio_fwd: dup() in/out failed"); 1585 if ((c = channel_connect_stdio_fwd(ssh, options.stdio_forward_host, 1586 options.stdio_forward_port, in, out)) == NULL) 1587 fatal("%s: channel_connect_stdio_fwd failed", __func__); 1588 channel_register_cleanup(ssh, c->self, client_cleanup_stdio_fwd, 0); 1589 channel_register_open_confirm(ssh, c->self, ssh_stdio_confirm, NULL); 1590 } 1591 1592 static void 1593 ssh_init_forwarding(struct ssh *ssh, char **ifname) 1594 { 1595 int success = 0; 1596 int i; 1597 1598 /* Initiate local TCP/IP port forwardings. */ 1599 for (i = 0; i < options.num_local_forwards; i++) { 1600 debug("Local connections to %.200s:%d forwarded to remote " 1601 "address %.200s:%d", 1602 (options.local_forwards[i].listen_path != NULL) ? 1603 options.local_forwards[i].listen_path : 1604 (options.local_forwards[i].listen_host == NULL) ? 1605 (options.fwd_opts.gateway_ports ? "*" : "LOCALHOST") : 1606 options.local_forwards[i].listen_host, 1607 options.local_forwards[i].listen_port, 1608 (options.local_forwards[i].connect_path != NULL) ? 1609 options.local_forwards[i].connect_path : 1610 options.local_forwards[i].connect_host, 1611 options.local_forwards[i].connect_port); 1612 success += channel_setup_local_fwd_listener(ssh, 1613 &options.local_forwards[i], &options.fwd_opts); 1614 } 1615 if (i > 0 && success != i && options.exit_on_forward_failure) 1616 fatal("Could not request local forwarding."); 1617 if (i > 0 && success == 0) 1618 error("Could not request local forwarding."); 1619 1620 /* Initiate remote TCP/IP port forwardings. */ 1621 for (i = 0; i < options.num_remote_forwards; i++) { 1622 debug("Remote connections from %.200s:%d forwarded to " 1623 "local address %.200s:%d", 1624 (options.remote_forwards[i].listen_path != NULL) ? 1625 options.remote_forwards[i].listen_path : 1626 (options.remote_forwards[i].listen_host == NULL) ? 1627 "LOCALHOST" : options.remote_forwards[i].listen_host, 1628 options.remote_forwards[i].listen_port, 1629 (options.remote_forwards[i].connect_path != NULL) ? 1630 options.remote_forwards[i].connect_path : 1631 options.remote_forwards[i].connect_host, 1632 options.remote_forwards[i].connect_port); 1633 options.remote_forwards[i].handle = 1634 channel_request_remote_forwarding(ssh, 1635 &options.remote_forwards[i]); 1636 if (options.remote_forwards[i].handle < 0) { 1637 if (options.exit_on_forward_failure) 1638 fatal("Could not request remote forwarding."); 1639 else 1640 logit("Warning: Could not request remote " 1641 "forwarding."); 1642 } else { 1643 client_register_global_confirm( 1644 ssh_confirm_remote_forward, 1645 &options.remote_forwards[i]); 1646 } 1647 } 1648 1649 /* Initiate tunnel forwarding. */ 1650 if (options.tun_open != SSH_TUNMODE_NO) { 1651 if ((*ifname = client_request_tun_fwd(ssh, 1652 options.tun_open, options.tun_local, 1653 options.tun_remote)) == NULL) { 1654 if (options.exit_on_forward_failure) 1655 fatal("Could not request tunnel forwarding."); 1656 else 1657 error("Could not request tunnel forwarding."); 1658 } 1659 } 1660 } 1661 1662 static void 1663 check_agent_present(void) 1664 { 1665 int r; 1666 1667 if (options.forward_agent) { 1668 /* Clear agent forwarding if we don't have an agent. */ 1669 if ((r = ssh_get_authentication_socket(NULL)) != 0) { 1670 options.forward_agent = 0; 1671 if (r != SSH_ERR_AGENT_NOT_PRESENT) 1672 debug("ssh_get_authentication_socket: %s", 1673 ssh_err(r)); 1674 } 1675 } 1676 } 1677 1678 static void 1679 ssh_session2_setup(struct ssh *ssh, int id, int success, void *arg) 1680 { 1681 extern char **environ; 1682 const char *display; 1683 int interactive = tty_flag; 1684 char *proto = NULL, *data = NULL; 1685 1686 if (!success) 1687 return; /* No need for error message, channels code sens one */ 1688 1689 display = getenv("DISPLAY"); 1690 if (display == NULL && options.forward_x11) 1691 debug("X11 forwarding requested but DISPLAY not set"); 1692 if (options.forward_x11 && client_x11_get_proto(ssh, display, 1693 options.xauth_location, options.forward_x11_trusted, 1694 options.forward_x11_timeout, &proto, &data) == 0) { 1695 /* Request forwarding with authentication spoofing. */ 1696 debug("Requesting X11 forwarding with authentication " 1697 "spoofing."); 1698 x11_request_forwarding_with_spoofing(ssh, id, display, proto, 1699 data, 1); 1700 client_expect_confirm(ssh, id, "X11 forwarding", CONFIRM_WARN); 1701 /* XXX exit_on_forward_failure */ 1702 interactive = 1; 1703 } 1704 1705 check_agent_present(); 1706 if (options.forward_agent) { 1707 debug("Requesting authentication agent forwarding."); 1708 channel_request_start(ssh, id, "auth-agent-req@openssh.com", 0); 1709 packet_send(); 1710 } 1711 1712 /* Tell the packet module whether this is an interactive session. */ 1713 packet_set_interactive(interactive, 1714 options.ip_qos_interactive, options.ip_qos_bulk); 1715 1716 client_session2_setup(ssh, id, tty_flag, subsystem_flag, getenv("TERM"), 1717 NULL, fileno(stdin), &command, environ); 1718 } 1719 1720 /* open new channel for a session */ 1721 static int 1722 ssh_session2_open(struct ssh *ssh) 1723 { 1724 Channel *c; 1725 int window, packetmax, in, out, err; 1726 1727 if (stdin_null_flag) { 1728 in = open(_PATH_DEVNULL, O_RDONLY); 1729 } else { 1730 in = dup(STDIN_FILENO); 1731 } 1732 out = dup(STDOUT_FILENO); 1733 err = dup(STDERR_FILENO); 1734 1735 if (in < 0 || out < 0 || err < 0) 1736 fatal("dup() in/out/err failed"); 1737 1738 /* enable nonblocking unless tty */ 1739 if (!isatty(in)) 1740 set_nonblock(in); 1741 if (!isatty(out)) 1742 set_nonblock(out); 1743 if (!isatty(err)) 1744 set_nonblock(err); 1745 1746 window = CHAN_SES_WINDOW_DEFAULT; 1747 packetmax = CHAN_SES_PACKET_DEFAULT; 1748 if (tty_flag) { 1749 window >>= 1; 1750 packetmax >>= 1; 1751 } 1752 c = channel_new(ssh, 1753 "session", SSH_CHANNEL_OPENING, in, out, err, 1754 window, packetmax, CHAN_EXTENDED_WRITE, 1755 "client-session", /*nonblock*/0); 1756 1757 debug3("%s: channel_new: %d", __func__, c->self); 1758 1759 channel_send_open(ssh, c->self); 1760 if (!no_shell_flag) 1761 channel_register_open_confirm(ssh, c->self, 1762 ssh_session2_setup, NULL); 1763 1764 return c->self; 1765 } 1766 1767 static int 1768 ssh_session2(struct ssh *ssh, struct passwd *pw) 1769 { 1770 int devnull, id = -1; 1771 char *cp, *tun_fwd_ifname = NULL; 1772 1773 /* XXX should be pre-session */ 1774 if (!options.control_persist) 1775 ssh_init_stdio_forwarding(ssh); 1776 1777 ssh_init_forwarding(ssh, &tun_fwd_ifname); 1778 1779 if (options.local_command != NULL) { 1780 debug3("expanding LocalCommand: %s", options.local_command); 1781 cp = options.local_command; 1782 options.local_command = percent_expand(cp, 1783 "C", conn_hash_hex, 1784 "L", shorthost, 1785 "d", pw->pw_dir, 1786 "h", host, 1787 "l", thishost, 1788 "n", host_arg, 1789 "p", portstr, 1790 "r", options.user, 1791 "u", pw->pw_name, 1792 "T", tun_fwd_ifname == NULL ? "NONE" : tun_fwd_ifname, 1793 (char *)NULL); 1794 debug3("expanded LocalCommand: %s", options.local_command); 1795 free(cp); 1796 } 1797 1798 /* Start listening for multiplex clients */ 1799 if (!packet_get_mux()) 1800 muxserver_listen(ssh); 1801 1802 /* 1803 * If we are in control persist mode and have a working mux listen 1804 * socket, then prepare to background ourselves and have a foreground 1805 * client attach as a control slave. 1806 * NB. we must save copies of the flags that we override for 1807 * the backgrounding, since we defer attachment of the slave until 1808 * after the connection is fully established (in particular, 1809 * async rfwd replies have been received for ExitOnForwardFailure). 1810 */ 1811 if (options.control_persist && muxserver_sock != -1) { 1812 ostdin_null_flag = stdin_null_flag; 1813 ono_shell_flag = no_shell_flag; 1814 orequest_tty = options.request_tty; 1815 otty_flag = tty_flag; 1816 stdin_null_flag = 1; 1817 no_shell_flag = 1; 1818 tty_flag = 0; 1819 if (!fork_after_authentication_flag) 1820 need_controlpersist_detach = 1; 1821 fork_after_authentication_flag = 1; 1822 } 1823 /* 1824 * ControlPersist mux listen socket setup failed, attempt the 1825 * stdio forward setup that we skipped earlier. 1826 */ 1827 if (options.control_persist && muxserver_sock == -1) 1828 ssh_init_stdio_forwarding(ssh); 1829 1830 if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN)) 1831 id = ssh_session2_open(ssh); 1832 else { 1833 packet_set_interactive( 1834 options.control_master == SSHCTL_MASTER_NO, 1835 options.ip_qos_interactive, options.ip_qos_bulk); 1836 } 1837 1838 /* If we don't expect to open a new session, then disallow it */ 1839 if (options.control_master == SSHCTL_MASTER_NO && 1840 (datafellows & SSH_NEW_OPENSSH)) { 1841 debug("Requesting no-more-sessions@openssh.com"); 1842 packet_start(SSH2_MSG_GLOBAL_REQUEST); 1843 packet_put_cstring("no-more-sessions@openssh.com"); 1844 packet_put_char(0); 1845 packet_send(); 1846 } 1847 1848 /* Execute a local command */ 1849 if (options.local_command != NULL && 1850 options.permit_local_command) 1851 ssh_local_cmd(options.local_command); 1852 1853 /* 1854 * stdout is now owned by the session channel; clobber it here 1855 * so future channel closes are propagated to the local fd. 1856 * NB. this can only happen after LocalCommand has completed, 1857 * as it may want to write to stdout. 1858 */ 1859 if (!need_controlpersist_detach) { 1860 if ((devnull = open(_PATH_DEVNULL, O_WRONLY)) == -1) 1861 error("%s: open %s: %s", __func__, 1862 _PATH_DEVNULL, strerror(errno)); 1863 if (dup2(devnull, STDOUT_FILENO) < 0) 1864 fatal("%s: dup2() stdout failed", __func__); 1865 if (devnull > STDERR_FILENO) 1866 close(devnull); 1867 } 1868 1869 /* 1870 * If requested and we are not interested in replies to remote 1871 * forwarding requests, then let ssh continue in the background. 1872 */ 1873 if (fork_after_authentication_flag) { 1874 if (options.exit_on_forward_failure && 1875 options.num_remote_forwards > 0) { 1876 debug("deferring postauth fork until remote forward " 1877 "confirmation received"); 1878 } else 1879 fork_postauth(); 1880 } 1881 1882 return client_loop(ssh, tty_flag, tty_flag ? 1883 options.escape_char : SSH_ESCAPECHAR_NONE, id); 1884 } 1885 1886 /* Loads all IdentityFile and CertificateFile keys */ 1887 static void 1888 load_public_identity_files(struct passwd *pw) 1889 { 1890 char *filename, *cp; 1891 struct sshkey *public; 1892 int i; 1893 u_int n_ids, n_certs; 1894 char *identity_files[SSH_MAX_IDENTITY_FILES]; 1895 struct sshkey *identity_keys[SSH_MAX_IDENTITY_FILES]; 1896 char *certificate_files[SSH_MAX_CERTIFICATE_FILES]; 1897 struct sshkey *certificates[SSH_MAX_CERTIFICATE_FILES]; 1898 #ifdef ENABLE_PKCS11 1899 struct sshkey **keys; 1900 int nkeys; 1901 #endif /* PKCS11 */ 1902 1903 n_ids = n_certs = 0; 1904 memset(identity_files, 0, sizeof(identity_files)); 1905 memset(identity_keys, 0, sizeof(identity_keys)); 1906 memset(certificate_files, 0, sizeof(certificate_files)); 1907 memset(certificates, 0, sizeof(certificates)); 1908 1909 #ifdef ENABLE_PKCS11 1910 if (options.pkcs11_provider != NULL && 1911 options.num_identity_files < SSH_MAX_IDENTITY_FILES && 1912 (pkcs11_init(!options.batch_mode) == 0) && 1913 (nkeys = pkcs11_add_provider(options.pkcs11_provider, NULL, 1914 &keys)) > 0) { 1915 for (i = 0; i < nkeys; i++) { 1916 if (n_ids >= SSH_MAX_IDENTITY_FILES) { 1917 key_free(keys[i]); 1918 continue; 1919 } 1920 identity_keys[n_ids] = keys[i]; 1921 identity_files[n_ids] = 1922 xstrdup(options.pkcs11_provider); /* XXX */ 1923 n_ids++; 1924 } 1925 free(keys); 1926 } 1927 #endif /* ENABLE_PKCS11 */ 1928 if ((pw = getpwuid(original_real_uid)) == NULL) 1929 fatal("load_public_identity_files: getpwuid failed"); 1930 for (i = 0; i < options.num_identity_files; i++) { 1931 if (n_ids >= SSH_MAX_IDENTITY_FILES || 1932 strcasecmp(options.identity_files[i], "none") == 0) { 1933 free(options.identity_files[i]); 1934 options.identity_files[i] = NULL; 1935 continue; 1936 } 1937 cp = tilde_expand_filename(options.identity_files[i], 1938 original_real_uid); 1939 filename = percent_expand(cp, "d", pw->pw_dir, 1940 "u", pw->pw_name, "l", thishost, "h", host, 1941 "r", options.user, (char *)NULL); 1942 free(cp); 1943 public = key_load_public(filename, NULL); 1944 debug("identity file %s type %d", filename, 1945 public ? public->type : -1); 1946 free(options.identity_files[i]); 1947 identity_files[n_ids] = filename; 1948 identity_keys[n_ids] = public; 1949 1950 if (++n_ids >= SSH_MAX_IDENTITY_FILES) 1951 continue; 1952 1953 /* 1954 * If no certificates have been explicitly listed then try 1955 * to add the default certificate variant too. 1956 */ 1957 if (options.num_certificate_files != 0) 1958 continue; 1959 xasprintf(&cp, "%s-cert", filename); 1960 public = key_load_public(cp, NULL); 1961 debug("identity file %s type %d", cp, 1962 public ? public->type : -1); 1963 if (public == NULL) { 1964 free(cp); 1965 continue; 1966 } 1967 if (!key_is_cert(public)) { 1968 debug("%s: key %s type %s is not a certificate", 1969 __func__, cp, key_type(public)); 1970 key_free(public); 1971 free(cp); 1972 continue; 1973 } 1974 /* NB. leave filename pointing to private key */ 1975 identity_files[n_ids] = xstrdup(filename); 1976 identity_keys[n_ids] = public; 1977 n_ids++; 1978 } 1979 1980 if (options.num_certificate_files > SSH_MAX_CERTIFICATE_FILES) 1981 fatal("%s: too many certificates", __func__); 1982 for (i = 0; i < options.num_certificate_files; i++) { 1983 cp = tilde_expand_filename(options.certificate_files[i], 1984 original_real_uid); 1985 filename = percent_expand(cp, "d", pw->pw_dir, 1986 "u", pw->pw_name, "l", thishost, "h", host, 1987 "r", options.user, (char *)NULL); 1988 free(cp); 1989 1990 public = key_load_public(filename, NULL); 1991 debug("certificate file %s type %d", filename, 1992 public ? public->type : -1); 1993 free(options.certificate_files[i]); 1994 options.certificate_files[i] = NULL; 1995 if (public == NULL) { 1996 free(filename); 1997 continue; 1998 } 1999 if (!key_is_cert(public)) { 2000 debug("%s: key %s type %s is not a certificate", 2001 __func__, filename, key_type(public)); 2002 key_free(public); 2003 free(filename); 2004 continue; 2005 } 2006 certificate_files[n_certs] = filename; 2007 certificates[n_certs] = public; 2008 ++n_certs; 2009 } 2010 2011 options.num_identity_files = n_ids; 2012 memcpy(options.identity_files, identity_files, sizeof(identity_files)); 2013 memcpy(options.identity_keys, identity_keys, sizeof(identity_keys)); 2014 2015 options.num_certificate_files = n_certs; 2016 memcpy(options.certificate_files, 2017 certificate_files, sizeof(certificate_files)); 2018 memcpy(options.certificates, certificates, sizeof(certificates)); 2019 } 2020 2021 static void 2022 main_sigchld_handler(int sig) 2023 { 2024 int save_errno = errno; 2025 pid_t pid; 2026 int status; 2027 2028 while ((pid = waitpid(-1, &status, WNOHANG)) > 0 || 2029 (pid < 0 && errno == EINTR)) 2030 ; 2031 2032 signal(sig, main_sigchld_handler); 2033 errno = save_errno; 2034 } 2035