1 /* $OpenBSD: ssh.c,v 1.477 2018/04/14 21:50:41 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_interface]\n" 189 " [-b bind_address] [-c cipher_spec] [-D [bind_address:]port]\n" 190 " [-E log_file] [-e escape_char] [-F configfile] [-I pkcs11]\n" 191 " [-i identity_file] [-J [user@]host[:port]] [-L address]\n" 192 " [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n" 193 " [-Q query_option] [-R address] [-S ctl_path] [-W host:port]\n" 194 " [-w local_tun[:remote_tun]] 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 /* Returns non-zero if name can only be an address and not a hostname */ 259 static int 260 is_addr_fast(const char *name) 261 { 262 return (strchr(name, '%') != NULL || strchr(name, ':') != NULL || 263 strspn(name, "0123456789.") == strlen(name)); 264 } 265 266 /* Returns non-zero if name represents a valid, single address */ 267 static int 268 is_addr(const char *name) 269 { 270 char strport[NI_MAXSERV]; 271 struct addrinfo hints, *res; 272 273 if (is_addr_fast(name)) 274 return 1; 275 276 snprintf(strport, sizeof strport, "%u", default_ssh_port()); 277 memset(&hints, 0, sizeof(hints)); 278 hints.ai_family = options.address_family == -1 ? 279 AF_UNSPEC : options.address_family; 280 hints.ai_socktype = SOCK_STREAM; 281 hints.ai_flags = AI_NUMERICHOST|AI_NUMERICSERV; 282 if (getaddrinfo(name, strport, &hints, &res) != 0) 283 return 0; 284 if (res == NULL || res->ai_next != NULL) { 285 freeaddrinfo(res); 286 return 0; 287 } 288 freeaddrinfo(res); 289 return 1; 290 } 291 292 /* 293 * Attempt to resolve a numeric host address / port to a single address. 294 * Returns a canonical address string. 295 * Returns NULL on failure. 296 * NB. this function must operate with a options having undefined members. 297 */ 298 static struct addrinfo * 299 resolve_addr(const char *name, int port, char *caddr, size_t clen) 300 { 301 char addr[NI_MAXHOST], strport[NI_MAXSERV]; 302 struct addrinfo hints, *res; 303 int gaierr; 304 305 if (port <= 0) 306 port = default_ssh_port(); 307 snprintf(strport, sizeof strport, "%u", port); 308 memset(&hints, 0, sizeof(hints)); 309 hints.ai_family = options.address_family == -1 ? 310 AF_UNSPEC : options.address_family; 311 hints.ai_socktype = SOCK_STREAM; 312 hints.ai_flags = AI_NUMERICHOST|AI_NUMERICSERV; 313 if ((gaierr = getaddrinfo(name, strport, &hints, &res)) != 0) { 314 debug2("%s: could not resolve name %.100s as address: %s", 315 __func__, name, ssh_gai_strerror(gaierr)); 316 return NULL; 317 } 318 if (res == NULL) { 319 debug("%s: getaddrinfo %.100s returned no addresses", 320 __func__, name); 321 return NULL; 322 } 323 if (res->ai_next != NULL) { 324 debug("%s: getaddrinfo %.100s returned multiple addresses", 325 __func__, name); 326 goto fail; 327 } 328 if ((gaierr = getnameinfo(res->ai_addr, res->ai_addrlen, 329 addr, sizeof(addr), NULL, 0, NI_NUMERICHOST)) != 0) { 330 debug("%s: Could not format address for name %.100s: %s", 331 __func__, name, ssh_gai_strerror(gaierr)); 332 goto fail; 333 } 334 if (strlcpy(caddr, addr, clen) >= clen) { 335 error("%s: host \"%s\" addr \"%s\" too long (max %lu)", 336 __func__, name, addr, (u_long)clen); 337 if (clen > 0) 338 *caddr = '\0'; 339 fail: 340 freeaddrinfo(res); 341 return NULL; 342 } 343 return res; 344 } 345 346 /* 347 * Check whether the cname is a permitted replacement for the hostname 348 * and perform the replacement if it is. 349 * NB. this function must operate with a options having undefined members. 350 */ 351 static int 352 check_follow_cname(int direct, char **namep, const char *cname) 353 { 354 int i; 355 struct allowed_cname *rule; 356 357 if (*cname == '\0' || options.num_permitted_cnames == 0 || 358 strcmp(*namep, cname) == 0) 359 return 0; 360 if (options.canonicalize_hostname == SSH_CANONICALISE_NO) 361 return 0; 362 /* 363 * Don't attempt to canonicalize names that will be interpreted by 364 * a proxy or jump host unless the user specifically requests so. 365 */ 366 if (!direct && 367 options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS) 368 return 0; 369 debug3("%s: check \"%s\" CNAME \"%s\"", __func__, *namep, cname); 370 for (i = 0; i < options.num_permitted_cnames; i++) { 371 rule = options.permitted_cnames + i; 372 if (match_pattern_list(*namep, rule->source_list, 1) != 1 || 373 match_pattern_list(cname, rule->target_list, 1) != 1) 374 continue; 375 verbose("Canonicalized DNS aliased hostname " 376 "\"%s\" => \"%s\"", *namep, cname); 377 free(*namep); 378 *namep = xstrdup(cname); 379 return 1; 380 } 381 return 0; 382 } 383 384 /* 385 * Attempt to resolve the supplied hostname after applying the user's 386 * canonicalization rules. Returns the address list for the host or NULL 387 * if no name was found after canonicalization. 388 * NB. this function must operate with a options having undefined members. 389 */ 390 static struct addrinfo * 391 resolve_canonicalize(char **hostp, int port) 392 { 393 int i, direct, ndots; 394 char *cp, *fullhost, newname[NI_MAXHOST]; 395 struct addrinfo *addrs; 396 397 /* 398 * Attempt to canonicalise addresses, regardless of 399 * whether hostname canonicalisation was requested 400 */ 401 if ((addrs = resolve_addr(*hostp, port, 402 newname, sizeof(newname))) != NULL) { 403 debug2("%s: hostname %.100s is address", __func__, *hostp); 404 if (strcasecmp(*hostp, newname) != 0) { 405 debug2("%s: canonicalised address \"%s\" => \"%s\"", 406 __func__, *hostp, newname); 407 free(*hostp); 408 *hostp = xstrdup(newname); 409 } 410 return addrs; 411 } 412 413 /* 414 * If this looks like an address but didn't parse as one, it might 415 * be an address with an invalid interface scope. Skip further 416 * attempts at canonicalisation. 417 */ 418 if (is_addr_fast(*hostp)) { 419 debug("%s: hostname %.100s is an unrecognised address", 420 __func__, *hostp); 421 return NULL; 422 } 423 424 if (options.canonicalize_hostname == SSH_CANONICALISE_NO) 425 return NULL; 426 427 /* 428 * Don't attempt to canonicalize names that will be interpreted by 429 * a proxy unless the user specifically requests so. 430 */ 431 direct = option_clear_or_none(options.proxy_command) && 432 options.jump_host == NULL; 433 if (!direct && 434 options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS) 435 return NULL; 436 437 /* If domain name is anchored, then resolve it now */ 438 if ((*hostp)[strlen(*hostp) - 1] == '.') { 439 debug3("%s: name is fully qualified", __func__); 440 fullhost = xstrdup(*hostp); 441 if ((addrs = resolve_host(fullhost, port, 0, 442 newname, sizeof(newname))) != NULL) 443 goto found; 444 free(fullhost); 445 goto notfound; 446 } 447 448 /* Don't apply canonicalization to sufficiently-qualified hostnames */ 449 ndots = 0; 450 for (cp = *hostp; *cp != '\0'; cp++) { 451 if (*cp == '.') 452 ndots++; 453 } 454 if (ndots > options.canonicalize_max_dots) { 455 debug3("%s: not canonicalizing hostname \"%s\" (max dots %d)", 456 __func__, *hostp, options.canonicalize_max_dots); 457 return NULL; 458 } 459 /* Attempt each supplied suffix */ 460 for (i = 0; i < options.num_canonical_domains; i++) { 461 *newname = '\0'; 462 xasprintf(&fullhost, "%s.%s.", *hostp, 463 options.canonical_domains[i]); 464 debug3("%s: attempting \"%s\" => \"%s\"", __func__, 465 *hostp, fullhost); 466 if ((addrs = resolve_host(fullhost, port, 0, 467 newname, sizeof(newname))) == NULL) { 468 free(fullhost); 469 continue; 470 } 471 found: 472 /* Remove trailing '.' */ 473 fullhost[strlen(fullhost) - 1] = '\0'; 474 /* Follow CNAME if requested */ 475 if (!check_follow_cname(direct, &fullhost, newname)) { 476 debug("Canonicalized hostname \"%s\" => \"%s\"", 477 *hostp, fullhost); 478 } 479 free(*hostp); 480 *hostp = fullhost; 481 return addrs; 482 } 483 notfound: 484 if (!options.canonicalize_fallback_local) 485 fatal("%s: Could not resolve host \"%s\"", __progname, *hostp); 486 debug2("%s: host %s not found in any suffix", __func__, *hostp); 487 return NULL; 488 } 489 490 /* 491 * Read per-user configuration file. Ignore the system wide config 492 * file if the user specifies a config file on the command line. 493 */ 494 static void 495 process_config_files(const char *host_name, struct passwd *pw, int post_canon) 496 { 497 char buf[PATH_MAX]; 498 int r; 499 500 if (config != NULL) { 501 if (strcasecmp(config, "none") != 0 && 502 !read_config_file(config, pw, host, host_name, &options, 503 SSHCONF_USERCONF | (post_canon ? SSHCONF_POSTCANON : 0))) 504 fatal("Can't open user config file %.100s: " 505 "%.100s", config, strerror(errno)); 506 } else { 507 r = snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir, 508 _PATH_SSH_USER_CONFFILE); 509 if (r > 0 && (size_t)r < sizeof(buf)) 510 (void)read_config_file(buf, pw, host, host_name, 511 &options, SSHCONF_CHECKPERM | SSHCONF_USERCONF | 512 (post_canon ? SSHCONF_POSTCANON : 0)); 513 514 /* Read systemwide configuration file after user config. */ 515 (void)read_config_file(_PATH_HOST_CONFIG_FILE, pw, 516 host, host_name, &options, 517 post_canon ? SSHCONF_POSTCANON : 0); 518 } 519 } 520 521 /* Rewrite the port number in an addrinfo list of addresses */ 522 static void 523 set_addrinfo_port(struct addrinfo *addrs, int port) 524 { 525 struct addrinfo *addr; 526 527 for (addr = addrs; addr != NULL; addr = addr->ai_next) { 528 switch (addr->ai_family) { 529 case AF_INET: 530 ((struct sockaddr_in *)addr->ai_addr)-> 531 sin_port = htons(port); 532 break; 533 case AF_INET6: 534 ((struct sockaddr_in6 *)addr->ai_addr)-> 535 sin6_port = htons(port); 536 break; 537 } 538 } 539 } 540 541 /* 542 * Main program for the ssh client. 543 */ 544 int 545 main(int ac, char **av) 546 { 547 struct ssh *ssh = NULL; 548 int i, r, opt, exit_status, use_syslog, direct, timeout_ms; 549 int was_addr, config_test = 0, opt_terminated = 0; 550 char *p, *cp, *line, *argv0, buf[PATH_MAX], *logfile; 551 char cname[NI_MAXHOST]; 552 struct stat st; 553 struct passwd *pw; 554 extern int optind, optreset; 555 extern char *optarg; 556 struct Forward fwd; 557 struct addrinfo *addrs = NULL; 558 struct ssh_digest_ctx *md; 559 u_char conn_hash[SSH_DIGEST_MAX_LENGTH]; 560 561 ssh_malloc_init(); /* must be called before any mallocs */ 562 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ 563 sanitise_stdfd(); 564 565 /* 566 * Discard other fds that are hanging around. These can cause problem 567 * with backgrounded ssh processes started by ControlPersist. 568 */ 569 closefrom(STDERR_FILENO + 1); 570 571 /* 572 * Save the original real uid. It will be needed later (uid-swapping 573 * may clobber the real uid). 574 */ 575 original_real_uid = getuid(); 576 original_effective_uid = geteuid(); 577 578 /* 579 * Use uid-swapping to give up root privileges for the duration of 580 * option processing. We will re-instantiate the rights when we are 581 * ready to create the privileged port, and will permanently drop 582 * them when the port has been created (actually, when the connection 583 * has been made, as we may need to create the port several times). 584 */ 585 PRIV_END; 586 587 /* If we are installed setuid root be careful to not drop core. */ 588 if (original_real_uid != original_effective_uid) { 589 struct rlimit rlim; 590 rlim.rlim_cur = rlim.rlim_max = 0; 591 if (setrlimit(RLIMIT_CORE, &rlim) < 0) 592 fatal("setrlimit failed: %.100s", strerror(errno)); 593 } 594 /* Get user data. */ 595 pw = getpwuid(original_real_uid); 596 if (!pw) { 597 logit("No user exists for uid %lu", (u_long)original_real_uid); 598 exit(255); 599 } 600 /* Take a copy of the returned structure. */ 601 pw = pwcopy(pw); 602 603 /* 604 * Set our umask to something reasonable, as some files are created 605 * with the default umask. This will make them world-readable but 606 * writable only by the owner, which is ok for all files for which we 607 * don't set the modes explicitly. 608 */ 609 umask(022); 610 611 setlocale(LC_CTYPE, ""); 612 613 /* 614 * Initialize option structure to indicate that no values have been 615 * set. 616 */ 617 initialize_options(&options); 618 619 /* 620 * Prepare main ssh transport/connection structures 621 */ 622 if ((ssh = ssh_alloc_session_state()) == NULL) 623 fatal("Couldn't allocate session state"); 624 channel_init_channels(ssh); 625 active_state = ssh; /* XXX legacy API compat */ 626 627 /* Parse command-line arguments. */ 628 host = NULL; 629 use_syslog = 0; 630 logfile = NULL; 631 argv0 = av[0]; 632 633 again: 634 while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx" 635 "AB:CD:E:F:GI:J:KL:MNO:PQ:R:S:TVw:W:XYy")) != -1) { 636 switch (opt) { 637 case '1': 638 fatal("SSH protocol v.1 is no longer supported"); 639 break; 640 case '2': 641 /* Ignored */ 642 break; 643 case '4': 644 options.address_family = AF_INET; 645 break; 646 case '6': 647 options.address_family = AF_INET6; 648 break; 649 case 'n': 650 stdin_null_flag = 1; 651 break; 652 case 'f': 653 fork_after_authentication_flag = 1; 654 stdin_null_flag = 1; 655 break; 656 case 'x': 657 options.forward_x11 = 0; 658 break; 659 case 'X': 660 options.forward_x11 = 1; 661 break; 662 case 'y': 663 use_syslog = 1; 664 break; 665 case 'E': 666 logfile = optarg; 667 break; 668 case 'G': 669 config_test = 1; 670 break; 671 case 'Y': 672 options.forward_x11 = 1; 673 options.forward_x11_trusted = 1; 674 break; 675 case 'g': 676 options.fwd_opts.gateway_ports = 1; 677 break; 678 case 'O': 679 if (options.stdio_forward_host != NULL) 680 fatal("Cannot specify multiplexing " 681 "command with -W"); 682 else if (muxclient_command != 0) 683 fatal("Multiplexing command already specified"); 684 if (strcmp(optarg, "check") == 0) 685 muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK; 686 else if (strcmp(optarg, "forward") == 0) 687 muxclient_command = SSHMUX_COMMAND_FORWARD; 688 else if (strcmp(optarg, "exit") == 0) 689 muxclient_command = SSHMUX_COMMAND_TERMINATE; 690 else if (strcmp(optarg, "stop") == 0) 691 muxclient_command = SSHMUX_COMMAND_STOP; 692 else if (strcmp(optarg, "cancel") == 0) 693 muxclient_command = SSHMUX_COMMAND_CANCEL_FWD; 694 else if (strcmp(optarg, "proxy") == 0) 695 muxclient_command = SSHMUX_COMMAND_PROXY; 696 else 697 fatal("Invalid multiplex command."); 698 break; 699 case 'P': /* deprecated */ 700 options.use_privileged_port = 0; 701 break; 702 case 'Q': 703 cp = NULL; 704 if (strcmp(optarg, "cipher") == 0) 705 cp = cipher_alg_list('\n', 0); 706 else if (strcmp(optarg, "cipher-auth") == 0) 707 cp = cipher_alg_list('\n', 1); 708 else if (strcmp(optarg, "mac") == 0) 709 cp = mac_alg_list('\n'); 710 else if (strcmp(optarg, "kex") == 0) 711 cp = kex_alg_list('\n'); 712 else if (strcmp(optarg, "key") == 0) 713 cp = sshkey_alg_list(0, 0, 0, '\n'); 714 else if (strcmp(optarg, "key-cert") == 0) 715 cp = sshkey_alg_list(1, 0, 0, '\n'); 716 else if (strcmp(optarg, "key-plain") == 0) 717 cp = sshkey_alg_list(0, 1, 0, '\n'); 718 else if (strcmp(optarg, "protocol-version") == 0) { 719 cp = xstrdup("2"); 720 } 721 if (cp == NULL) 722 fatal("Unsupported query \"%s\"", optarg); 723 printf("%s\n", cp); 724 free(cp); 725 exit(0); 726 break; 727 case 'a': 728 options.forward_agent = 0; 729 break; 730 case 'A': 731 options.forward_agent = 1; 732 break; 733 case 'k': 734 options.gss_deleg_creds = 0; 735 break; 736 case 'K': 737 options.gss_authentication = 1; 738 options.gss_deleg_creds = 1; 739 break; 740 case 'i': 741 p = tilde_expand_filename(optarg, original_real_uid); 742 if (stat(p, &st) < 0) 743 fprintf(stderr, "Warning: Identity file %s " 744 "not accessible: %s.\n", p, 745 strerror(errno)); 746 else 747 add_identity_file(&options, NULL, p, 1); 748 free(p); 749 break; 750 case 'I': 751 #ifdef ENABLE_PKCS11 752 free(options.pkcs11_provider); 753 options.pkcs11_provider = xstrdup(optarg); 754 #else 755 fprintf(stderr, "no support for PKCS#11.\n"); 756 #endif 757 break; 758 case 'J': 759 if (options.jump_host != NULL) 760 fatal("Only a single -J option permitted"); 761 if (options.proxy_command != NULL) 762 fatal("Cannot specify -J with ProxyCommand"); 763 if (parse_jump(optarg, &options, 1) == -1) 764 fatal("Invalid -J argument"); 765 options.proxy_command = xstrdup("none"); 766 break; 767 case 't': 768 if (options.request_tty == REQUEST_TTY_YES) 769 options.request_tty = REQUEST_TTY_FORCE; 770 else 771 options.request_tty = REQUEST_TTY_YES; 772 break; 773 case 'v': 774 if (debug_flag == 0) { 775 debug_flag = 1; 776 options.log_level = SYSLOG_LEVEL_DEBUG1; 777 } else { 778 if (options.log_level < SYSLOG_LEVEL_DEBUG3) { 779 debug_flag++; 780 options.log_level++; 781 } 782 } 783 break; 784 case 'V': 785 fprintf(stderr, "%s, %s\n", 786 SSH_VERSION, 787 #ifdef WITH_OPENSSL 788 SSLeay_version(SSLEAY_VERSION) 789 #else 790 "without OpenSSL" 791 #endif 792 ); 793 if (opt == 'V') 794 exit(0); 795 break; 796 case 'w': 797 if (options.tun_open == -1) 798 options.tun_open = SSH_TUNMODE_DEFAULT; 799 options.tun_local = a2tun(optarg, &options.tun_remote); 800 if (options.tun_local == SSH_TUNID_ERR) { 801 fprintf(stderr, 802 "Bad tun device '%s'\n", optarg); 803 exit(255); 804 } 805 break; 806 case 'W': 807 if (options.stdio_forward_host != NULL) 808 fatal("stdio forward already specified"); 809 if (muxclient_command != 0) 810 fatal("Cannot specify stdio forward with -O"); 811 if (parse_forward(&fwd, optarg, 1, 0)) { 812 options.stdio_forward_host = fwd.listen_host; 813 options.stdio_forward_port = fwd.listen_port; 814 free(fwd.connect_host); 815 } else { 816 fprintf(stderr, 817 "Bad stdio forwarding specification '%s'\n", 818 optarg); 819 exit(255); 820 } 821 options.request_tty = REQUEST_TTY_NO; 822 no_shell_flag = 1; 823 break; 824 case 'q': 825 options.log_level = SYSLOG_LEVEL_QUIET; 826 break; 827 case 'e': 828 if (optarg[0] == '^' && optarg[2] == 0 && 829 (u_char) optarg[1] >= 64 && 830 (u_char) optarg[1] < 128) 831 options.escape_char = (u_char) optarg[1] & 31; 832 else if (strlen(optarg) == 1) 833 options.escape_char = (u_char) optarg[0]; 834 else if (strcmp(optarg, "none") == 0) 835 options.escape_char = SSH_ESCAPECHAR_NONE; 836 else { 837 fprintf(stderr, "Bad escape character '%s'.\n", 838 optarg); 839 exit(255); 840 } 841 break; 842 case 'c': 843 if (!ciphers_valid(*optarg == '+' ? 844 optarg + 1 : optarg)) { 845 fprintf(stderr, "Unknown cipher type '%s'\n", 846 optarg); 847 exit(255); 848 } 849 free(options.ciphers); 850 options.ciphers = xstrdup(optarg); 851 break; 852 case 'm': 853 if (mac_valid(optarg)) { 854 free(options.macs); 855 options.macs = xstrdup(optarg); 856 } else { 857 fprintf(stderr, "Unknown mac type '%s'\n", 858 optarg); 859 exit(255); 860 } 861 break; 862 case 'M': 863 if (options.control_master == SSHCTL_MASTER_YES) 864 options.control_master = SSHCTL_MASTER_ASK; 865 else 866 options.control_master = SSHCTL_MASTER_YES; 867 break; 868 case 'p': 869 if (options.port == -1) { 870 options.port = a2port(optarg); 871 if (options.port <= 0) { 872 fprintf(stderr, "Bad port '%s'\n", 873 optarg); 874 exit(255); 875 } 876 } 877 break; 878 case 'l': 879 if (options.user == NULL) 880 options.user = optarg; 881 break; 882 883 case 'L': 884 if (parse_forward(&fwd, optarg, 0, 0)) 885 add_local_forward(&options, &fwd); 886 else { 887 fprintf(stderr, 888 "Bad local forwarding specification '%s'\n", 889 optarg); 890 exit(255); 891 } 892 break; 893 894 case 'R': 895 if (parse_forward(&fwd, optarg, 0, 1) || 896 parse_forward(&fwd, optarg, 1, 1)) { 897 add_remote_forward(&options, &fwd); 898 } else { 899 fprintf(stderr, 900 "Bad remote forwarding specification " 901 "'%s'\n", optarg); 902 exit(255); 903 } 904 break; 905 906 case 'D': 907 if (parse_forward(&fwd, optarg, 1, 0)) { 908 add_local_forward(&options, &fwd); 909 } else { 910 fprintf(stderr, 911 "Bad dynamic forwarding specification " 912 "'%s'\n", optarg); 913 exit(255); 914 } 915 break; 916 917 case 'C': 918 options.compression = 1; 919 break; 920 case 'N': 921 no_shell_flag = 1; 922 options.request_tty = REQUEST_TTY_NO; 923 break; 924 case 'T': 925 options.request_tty = REQUEST_TTY_NO; 926 break; 927 case 'o': 928 line = xstrdup(optarg); 929 if (process_config_line(&options, pw, 930 host ? host : "", host ? host : "", line, 931 "command-line", 0, NULL, SSHCONF_USERCONF) != 0) 932 exit(255); 933 free(line); 934 break; 935 case 's': 936 subsystem_flag = 1; 937 break; 938 case 'S': 939 free(options.control_path); 940 options.control_path = xstrdup(optarg); 941 break; 942 case 'b': 943 options.bind_address = optarg; 944 break; 945 case 'B': 946 options.bind_interface = optarg; 947 break; 948 case 'F': 949 config = optarg; 950 break; 951 default: 952 usage(); 953 } 954 } 955 956 if (optind > 1 && strcmp(av[optind - 1], "--") == 0) 957 opt_terminated = 1; 958 959 ac -= optind; 960 av += optind; 961 962 if (ac > 0 && !host) { 963 int tport; 964 char *tuser; 965 switch (parse_ssh_uri(*av, &tuser, &host, &tport)) { 966 case -1: 967 usage(); 968 break; 969 case 0: 970 if (options.user == NULL) { 971 options.user = tuser; 972 tuser = NULL; 973 } 974 free(tuser); 975 if (options.port == -1 && tport != -1) 976 options.port = tport; 977 break; 978 default: 979 p = xstrdup(*av); 980 cp = strrchr(p, '@'); 981 if (cp != NULL) { 982 if (cp == p) 983 usage(); 984 if (options.user == NULL) { 985 options.user = p; 986 p = NULL; 987 } 988 *cp++ = '\0'; 989 host = xstrdup(cp); 990 free(p); 991 } else 992 host = p; 993 break; 994 } 995 if (ac > 1 && !opt_terminated) { 996 optind = optreset = 1; 997 goto again; 998 } 999 ac--, av++; 1000 } 1001 1002 /* Check that we got a host name. */ 1003 if (!host) 1004 usage(); 1005 1006 host_arg = xstrdup(host); 1007 1008 #ifdef WITH_OPENSSL 1009 OpenSSL_add_all_algorithms(); 1010 ERR_load_crypto_strings(); 1011 #endif 1012 1013 /* Initialize the command to execute on remote host. */ 1014 buffer_init(&command); 1015 1016 /* 1017 * Save the command to execute on the remote host in a buffer. There 1018 * is no limit on the length of the command, except by the maximum 1019 * packet size. Also sets the tty flag if there is no command. 1020 */ 1021 if (!ac) { 1022 /* No command specified - execute shell on a tty. */ 1023 if (subsystem_flag) { 1024 fprintf(stderr, 1025 "You must specify a subsystem to invoke.\n"); 1026 usage(); 1027 } 1028 } else { 1029 /* A command has been specified. Store it into the buffer. */ 1030 for (i = 0; i < ac; i++) { 1031 if (i) 1032 buffer_append(&command, " ", 1); 1033 buffer_append(&command, av[i], strlen(av[i])); 1034 } 1035 } 1036 1037 /* 1038 * Initialize "log" output. Since we are the client all output 1039 * goes to stderr unless otherwise specified by -y or -E. 1040 */ 1041 if (use_syslog && logfile != NULL) 1042 fatal("Can't specify both -y and -E"); 1043 if (logfile != NULL) 1044 log_redirect_stderr_to(logfile); 1045 log_init(argv0, 1046 options.log_level == SYSLOG_LEVEL_NOT_SET ? 1047 SYSLOG_LEVEL_INFO : options.log_level, 1048 options.log_facility == SYSLOG_FACILITY_NOT_SET ? 1049 SYSLOG_FACILITY_USER : options.log_facility, 1050 !use_syslog); 1051 1052 if (debug_flag) 1053 logit("%s, %s", SSH_VERSION, 1054 #ifdef WITH_OPENSSL 1055 SSLeay_version(SSLEAY_VERSION) 1056 #else 1057 "without OpenSSL" 1058 #endif 1059 ); 1060 1061 /* Parse the configuration files */ 1062 process_config_files(host_arg, pw, 0); 1063 1064 /* Hostname canonicalisation needs a few options filled. */ 1065 fill_default_options_for_canonicalization(&options); 1066 1067 /* If the user has replaced the hostname then take it into use now */ 1068 if (options.hostname != NULL) { 1069 /* NB. Please keep in sync with readconf.c:match_cfg_line() */ 1070 cp = percent_expand(options.hostname, 1071 "h", host, (char *)NULL); 1072 free(host); 1073 host = cp; 1074 free(options.hostname); 1075 options.hostname = xstrdup(host); 1076 } 1077 1078 /* Don't lowercase addresses, they will be explicitly canonicalised */ 1079 if ((was_addr = is_addr(host)) == 0) 1080 lowercase(host); 1081 1082 /* 1083 * Try to canonicalize if requested by configuration or the 1084 * hostname is an address. 1085 */ 1086 if (options.canonicalize_hostname != SSH_CANONICALISE_NO || was_addr) 1087 addrs = resolve_canonicalize(&host, options.port); 1088 1089 /* 1090 * If CanonicalizePermittedCNAMEs have been specified but 1091 * other canonicalization did not happen (by not being requested 1092 * or by failing with fallback) then the hostname may still be changed 1093 * as a result of CNAME following. 1094 * 1095 * Try to resolve the bare hostname name using the system resolver's 1096 * usual search rules and then apply the CNAME follow rules. 1097 * 1098 * Skip the lookup if a ProxyCommand is being used unless the user 1099 * has specifically requested canonicalisation for this case via 1100 * CanonicalizeHostname=always 1101 */ 1102 direct = option_clear_or_none(options.proxy_command) && 1103 options.jump_host == NULL; 1104 if (addrs == NULL && options.num_permitted_cnames != 0 && (direct || 1105 options.canonicalize_hostname == SSH_CANONICALISE_ALWAYS)) { 1106 if ((addrs = resolve_host(host, options.port, 1107 option_clear_or_none(options.proxy_command), 1108 cname, sizeof(cname))) == NULL) { 1109 /* Don't fatal proxied host names not in the DNS */ 1110 if (option_clear_or_none(options.proxy_command)) 1111 cleanup_exit(255); /* logged in resolve_host */ 1112 } else 1113 check_follow_cname(direct, &host, cname); 1114 } 1115 1116 /* 1117 * If canonicalisation is enabled then re-parse the configuration 1118 * files as new stanzas may match. 1119 */ 1120 if (options.canonicalize_hostname != 0) { 1121 debug("Re-reading configuration after hostname " 1122 "canonicalisation"); 1123 free(options.hostname); 1124 options.hostname = xstrdup(host); 1125 process_config_files(host_arg, pw, 1); 1126 /* 1127 * Address resolution happens early with canonicalisation 1128 * enabled and the port number may have changed since, so 1129 * reset it in address list 1130 */ 1131 if (addrs != NULL && options.port > 0) 1132 set_addrinfo_port(addrs, options.port); 1133 } 1134 1135 /* Fill configuration defaults. */ 1136 fill_default_options(&options); 1137 1138 /* 1139 * If ProxyJump option specified, then construct a ProxyCommand now. 1140 */ 1141 if (options.jump_host != NULL) { 1142 char port_s[8]; 1143 1144 /* Consistency check */ 1145 if (options.proxy_command != NULL) 1146 fatal("inconsistent options: ProxyCommand+ProxyJump"); 1147 /* Never use FD passing for ProxyJump */ 1148 options.proxy_use_fdpass = 0; 1149 snprintf(port_s, sizeof(port_s), "%d", options.jump_port); 1150 xasprintf(&options.proxy_command, 1151 "ssh%s%s%s%s%s%s%s%s%s%.*s -W '[%%h]:%%p' %s", 1152 /* Optional "-l user" argument if jump_user set */ 1153 options.jump_user == NULL ? "" : " -l ", 1154 options.jump_user == NULL ? "" : options.jump_user, 1155 /* Optional "-p port" argument if jump_port set */ 1156 options.jump_port <= 0 ? "" : " -p ", 1157 options.jump_port <= 0 ? "" : port_s, 1158 /* Optional additional jump hosts ",..." */ 1159 options.jump_extra == NULL ? "" : " -J ", 1160 options.jump_extra == NULL ? "" : options.jump_extra, 1161 /* Optional "-F" argumment if -F specified */ 1162 config == NULL ? "" : " -F ", 1163 config == NULL ? "" : config, 1164 /* Optional "-v" arguments if -v set */ 1165 debug_flag ? " -" : "", 1166 debug_flag, "vvv", 1167 /* Mandatory hostname */ 1168 options.jump_host); 1169 debug("Setting implicit ProxyCommand from ProxyJump: %s", 1170 options.proxy_command); 1171 } 1172 1173 if (options.port == 0) 1174 options.port = default_ssh_port(); 1175 channel_set_af(ssh, options.address_family); 1176 1177 /* Tidy and check options */ 1178 if (options.host_key_alias != NULL) 1179 lowercase(options.host_key_alias); 1180 if (options.proxy_command != NULL && 1181 strcmp(options.proxy_command, "-") == 0 && 1182 options.proxy_use_fdpass) 1183 fatal("ProxyCommand=- and ProxyUseFDPass are incompatible"); 1184 if (options.control_persist && 1185 options.update_hostkeys == SSH_UPDATE_HOSTKEYS_ASK) { 1186 debug("UpdateHostKeys=ask is incompatible with ControlPersist; " 1187 "disabling"); 1188 options.update_hostkeys = 0; 1189 } 1190 if (options.connection_attempts <= 0) 1191 fatal("Invalid number of ConnectionAttempts"); 1192 1193 if (original_effective_uid != 0) 1194 options.use_privileged_port = 0; 1195 1196 if (buffer_len(&command) != 0 && options.remote_command != NULL) 1197 fatal("Cannot execute command-line and remote command."); 1198 1199 /* Cannot fork to background if no command. */ 1200 if (fork_after_authentication_flag && buffer_len(&command) == 0 && 1201 options.remote_command == NULL && !no_shell_flag) 1202 fatal("Cannot fork into background without a command " 1203 "to execute."); 1204 1205 /* reinit */ 1206 log_init(argv0, options.log_level, options.log_facility, !use_syslog); 1207 1208 if (options.request_tty == REQUEST_TTY_YES || 1209 options.request_tty == REQUEST_TTY_FORCE) 1210 tty_flag = 1; 1211 1212 /* Allocate a tty by default if no command specified. */ 1213 if (buffer_len(&command) == 0 && options.remote_command == NULL) 1214 tty_flag = options.request_tty != REQUEST_TTY_NO; 1215 1216 /* Force no tty */ 1217 if (options.request_tty == REQUEST_TTY_NO || 1218 (muxclient_command && muxclient_command != SSHMUX_COMMAND_PROXY)) 1219 tty_flag = 0; 1220 /* Do not allocate a tty if stdin is not a tty. */ 1221 if ((!isatty(fileno(stdin)) || stdin_null_flag) && 1222 options.request_tty != REQUEST_TTY_FORCE) { 1223 if (tty_flag) 1224 logit("Pseudo-terminal will not be allocated because " 1225 "stdin is not a terminal."); 1226 tty_flag = 0; 1227 } 1228 1229 if (options.user == NULL) 1230 options.user = xstrdup(pw->pw_name); 1231 1232 /* Set up strings used to percent_expand() arguments */ 1233 if (gethostname(thishost, sizeof(thishost)) == -1) 1234 fatal("gethostname: %s", strerror(errno)); 1235 strlcpy(shorthost, thishost, sizeof(shorthost)); 1236 shorthost[strcspn(thishost, ".")] = '\0'; 1237 snprintf(portstr, sizeof(portstr), "%d", options.port); 1238 snprintf(uidstr, sizeof(uidstr), "%d", pw->pw_uid); 1239 1240 if ((md = ssh_digest_start(SSH_DIGEST_SHA1)) == NULL || 1241 ssh_digest_update(md, thishost, strlen(thishost)) < 0 || 1242 ssh_digest_update(md, host, strlen(host)) < 0 || 1243 ssh_digest_update(md, portstr, strlen(portstr)) < 0 || 1244 ssh_digest_update(md, options.user, strlen(options.user)) < 0 || 1245 ssh_digest_final(md, conn_hash, sizeof(conn_hash)) < 0) 1246 fatal("%s: mux digest failed", __func__); 1247 ssh_digest_free(md); 1248 conn_hash_hex = tohex(conn_hash, ssh_digest_bytes(SSH_DIGEST_SHA1)); 1249 1250 /* 1251 * Expand tokens in arguments. NB. LocalCommand is expanded later, 1252 * after port-forwarding is set up, so it may pick up any local 1253 * tunnel interface name allocated. 1254 */ 1255 if (options.remote_command != NULL) { 1256 debug3("expanding RemoteCommand: %s", options.remote_command); 1257 cp = options.remote_command; 1258 options.remote_command = percent_expand(cp, 1259 "C", conn_hash_hex, 1260 "L", shorthost, 1261 "d", pw->pw_dir, 1262 "h", host, 1263 "l", thishost, 1264 "n", host_arg, 1265 "p", portstr, 1266 "r", options.user, 1267 "u", pw->pw_name, 1268 (char *)NULL); 1269 debug3("expanded RemoteCommand: %s", options.remote_command); 1270 free(cp); 1271 buffer_append(&command, options.remote_command, 1272 strlen(options.remote_command)); 1273 } 1274 1275 if (options.control_path != NULL) { 1276 cp = tilde_expand_filename(options.control_path, 1277 original_real_uid); 1278 free(options.control_path); 1279 options.control_path = percent_expand(cp, 1280 "C", conn_hash_hex, 1281 "L", shorthost, 1282 "h", host, 1283 "l", thishost, 1284 "n", host_arg, 1285 "p", portstr, 1286 "r", options.user, 1287 "u", pw->pw_name, 1288 "i", uidstr, 1289 (char *)NULL); 1290 free(cp); 1291 } 1292 1293 if (config_test) { 1294 dump_client_config(&options, host); 1295 exit(0); 1296 } 1297 1298 if (muxclient_command != 0 && options.control_path == NULL) 1299 fatal("No ControlPath specified for \"-O\" command"); 1300 if (options.control_path != NULL) { 1301 int sock; 1302 if ((sock = muxclient(options.control_path)) >= 0) { 1303 ssh_packet_set_connection(ssh, sock, sock); 1304 packet_set_mux(); 1305 goto skip_connect; 1306 } 1307 } 1308 1309 /* 1310 * If hostname canonicalisation was not enabled, then we may not 1311 * have yet resolved the hostname. Do so now. 1312 */ 1313 if (addrs == NULL && options.proxy_command == NULL) { 1314 debug2("resolving \"%s\" port %d", host, options.port); 1315 if ((addrs = resolve_host(host, options.port, 1, 1316 cname, sizeof(cname))) == NULL) 1317 cleanup_exit(255); /* resolve_host logs the error */ 1318 } 1319 1320 timeout_ms = options.connection_timeout * 1000; 1321 1322 /* Open a connection to the remote host. */ 1323 if (ssh_connect(ssh, host, addrs, &hostaddr, options.port, 1324 options.address_family, options.connection_attempts, 1325 &timeout_ms, options.tcp_keep_alive, 1326 options.use_privileged_port) != 0) 1327 exit(255); 1328 1329 if (addrs != NULL) 1330 freeaddrinfo(addrs); 1331 1332 packet_set_timeout(options.server_alive_interval, 1333 options.server_alive_count_max); 1334 1335 ssh = active_state; /* XXX */ 1336 1337 if (timeout_ms > 0) 1338 debug3("timeout: %d ms remain after connect", timeout_ms); 1339 1340 /* 1341 * If we successfully made the connection, load the host private key 1342 * in case we will need it later for combined rsa-rhosts 1343 * authentication. This must be done before releasing extra 1344 * privileges, because the file is only readable by root. 1345 * If we cannot access the private keys, load the public keys 1346 * instead and try to execute the ssh-keysign helper instead. 1347 */ 1348 sensitive_data.nkeys = 0; 1349 sensitive_data.keys = NULL; 1350 sensitive_data.external_keysign = 0; 1351 if (options.hostbased_authentication) { 1352 sensitive_data.nkeys = 11; 1353 sensitive_data.keys = xcalloc(sensitive_data.nkeys, 1354 sizeof(struct sshkey)); /* XXX */ 1355 1356 PRIV_START; 1357 sensitive_data.keys[1] = key_load_private_cert(KEY_ECDSA, 1358 _PATH_HOST_ECDSA_KEY_FILE, "", NULL); 1359 sensitive_data.keys[2] = key_load_private_cert(KEY_ED25519, 1360 _PATH_HOST_ED25519_KEY_FILE, "", NULL); 1361 sensitive_data.keys[3] = key_load_private_cert(KEY_RSA, 1362 _PATH_HOST_RSA_KEY_FILE, "", NULL); 1363 sensitive_data.keys[4] = key_load_private_cert(KEY_DSA, 1364 _PATH_HOST_DSA_KEY_FILE, "", NULL); 1365 sensitive_data.keys[5] = key_load_private_type(KEY_ECDSA, 1366 _PATH_HOST_ECDSA_KEY_FILE, "", NULL, NULL); 1367 sensitive_data.keys[6] = key_load_private_type(KEY_ED25519, 1368 _PATH_HOST_ED25519_KEY_FILE, "", NULL, NULL); 1369 sensitive_data.keys[7] = key_load_private_type(KEY_RSA, 1370 _PATH_HOST_RSA_KEY_FILE, "", NULL, NULL); 1371 sensitive_data.keys[8] = key_load_private_type(KEY_DSA, 1372 _PATH_HOST_DSA_KEY_FILE, "", NULL, NULL); 1373 sensitive_data.keys[9] = key_load_private_cert(KEY_XMSS, 1374 _PATH_HOST_XMSS_KEY_FILE, "", NULL); 1375 sensitive_data.keys[10] = key_load_private_type(KEY_XMSS, 1376 _PATH_HOST_XMSS_KEY_FILE, "", NULL, NULL); 1377 PRIV_END; 1378 1379 if (options.hostbased_authentication == 1 && 1380 sensitive_data.keys[0] == NULL && 1381 sensitive_data.keys[5] == NULL && 1382 sensitive_data.keys[6] == NULL && 1383 sensitive_data.keys[7] == NULL && 1384 sensitive_data.keys[8] == NULL && 1385 sensitive_data.keys[9] == NULL) { 1386 sensitive_data.keys[1] = key_load_cert( 1387 _PATH_HOST_ECDSA_KEY_FILE); 1388 sensitive_data.keys[2] = key_load_cert( 1389 _PATH_HOST_ED25519_KEY_FILE); 1390 sensitive_data.keys[3] = key_load_cert( 1391 _PATH_HOST_RSA_KEY_FILE); 1392 sensitive_data.keys[4] = key_load_cert( 1393 _PATH_HOST_DSA_KEY_FILE); 1394 sensitive_data.keys[5] = key_load_public( 1395 _PATH_HOST_ECDSA_KEY_FILE, NULL); 1396 sensitive_data.keys[6] = key_load_public( 1397 _PATH_HOST_ED25519_KEY_FILE, NULL); 1398 sensitive_data.keys[7] = key_load_public( 1399 _PATH_HOST_RSA_KEY_FILE, NULL); 1400 sensitive_data.keys[8] = key_load_public( 1401 _PATH_HOST_DSA_KEY_FILE, NULL); 1402 sensitive_data.keys[9] = key_load_cert( 1403 _PATH_HOST_XMSS_KEY_FILE); 1404 sensitive_data.keys[10] = key_load_public( 1405 _PATH_HOST_XMSS_KEY_FILE, NULL); 1406 sensitive_data.external_keysign = 1; 1407 } 1408 } 1409 /* 1410 * Get rid of any extra privileges that we may have. We will no 1411 * longer need them. Also, extra privileges could make it very hard 1412 * to read identity files and other non-world-readable files from the 1413 * user's home directory if it happens to be on a NFS volume where 1414 * root is mapped to nobody. 1415 */ 1416 if (original_effective_uid == 0) { 1417 PRIV_START; 1418 permanently_set_uid(pw); 1419 } 1420 1421 /* 1422 * Now that we are back to our own permissions, create ~/.ssh 1423 * directory if it doesn't already exist. 1424 */ 1425 if (config == NULL) { 1426 r = snprintf(buf, sizeof buf, "%s%s%s", pw->pw_dir, 1427 strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR); 1428 if (r > 0 && (size_t)r < sizeof(buf) && stat(buf, &st) < 0) 1429 if (mkdir(buf, 0700) < 0) 1430 error("Could not create directory '%.200s'.", 1431 buf); 1432 } 1433 1434 /* load options.identity_files */ 1435 load_public_identity_files(pw); 1436 1437 /* optionally set the SSH_AUTHSOCKET_ENV_NAME variable */ 1438 if (options.identity_agent && 1439 strcmp(options.identity_agent, SSH_AUTHSOCKET_ENV_NAME) != 0) { 1440 if (strcmp(options.identity_agent, "none") == 0) { 1441 unsetenv(SSH_AUTHSOCKET_ENV_NAME); 1442 } else { 1443 p = tilde_expand_filename(options.identity_agent, 1444 original_real_uid); 1445 cp = percent_expand(p, "d", pw->pw_dir, 1446 "u", pw->pw_name, "l", thishost, "h", host, 1447 "r", options.user, (char *)NULL); 1448 setenv(SSH_AUTHSOCKET_ENV_NAME, cp, 1); 1449 free(cp); 1450 free(p); 1451 } 1452 } 1453 1454 /* Expand ~ in known host file names. */ 1455 tilde_expand_paths(options.system_hostfiles, 1456 options.num_system_hostfiles); 1457 tilde_expand_paths(options.user_hostfiles, options.num_user_hostfiles); 1458 1459 signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */ 1460 signal(SIGCHLD, main_sigchld_handler); 1461 1462 /* Log into the remote system. Never returns if the login fails. */ 1463 ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr, 1464 options.port, pw, timeout_ms); 1465 1466 if (packet_connection_is_on_socket()) { 1467 verbose("Authenticated to %s ([%s]:%d).", host, 1468 ssh_remote_ipaddr(ssh), ssh_remote_port(ssh)); 1469 } else { 1470 verbose("Authenticated to %s (via proxy).", host); 1471 } 1472 1473 /* We no longer need the private host keys. Clear them now. */ 1474 if (sensitive_data.nkeys != 0) { 1475 for (i = 0; i < sensitive_data.nkeys; i++) { 1476 if (sensitive_data.keys[i] != NULL) { 1477 /* Destroys contents safely */ 1478 debug3("clear hostkey %d", i); 1479 key_free(sensitive_data.keys[i]); 1480 sensitive_data.keys[i] = NULL; 1481 } 1482 } 1483 free(sensitive_data.keys); 1484 } 1485 for (i = 0; i < options.num_identity_files; i++) { 1486 free(options.identity_files[i]); 1487 options.identity_files[i] = NULL; 1488 if (options.identity_keys[i]) { 1489 key_free(options.identity_keys[i]); 1490 options.identity_keys[i] = NULL; 1491 } 1492 } 1493 for (i = 0; i < options.num_certificate_files; i++) { 1494 free(options.certificate_files[i]); 1495 options.certificate_files[i] = NULL; 1496 } 1497 1498 skip_connect: 1499 exit_status = ssh_session2(ssh, pw); 1500 packet_close(); 1501 1502 if (options.control_path != NULL && muxserver_sock != -1) 1503 unlink(options.control_path); 1504 1505 /* Kill ProxyCommand if it is running. */ 1506 ssh_kill_proxy_command(); 1507 1508 return exit_status; 1509 } 1510 1511 static void 1512 control_persist_detach(void) 1513 { 1514 pid_t pid; 1515 int devnull, keep_stderr; 1516 1517 debug("%s: backgrounding master process", __func__); 1518 1519 /* 1520 * master (current process) into the background, and make the 1521 * foreground process a client of the backgrounded master. 1522 */ 1523 switch ((pid = fork())) { 1524 case -1: 1525 fatal("%s: fork: %s", __func__, strerror(errno)); 1526 case 0: 1527 /* Child: master process continues mainloop */ 1528 break; 1529 default: 1530 /* Parent: set up mux slave to connect to backgrounded master */ 1531 debug2("%s: background process is %ld", __func__, (long)pid); 1532 stdin_null_flag = ostdin_null_flag; 1533 options.request_tty = orequest_tty; 1534 tty_flag = otty_flag; 1535 close(muxserver_sock); 1536 muxserver_sock = -1; 1537 options.control_master = SSHCTL_MASTER_NO; 1538 muxclient(options.control_path); 1539 /* muxclient() doesn't return on success. */ 1540 fatal("Failed to connect to new control master"); 1541 } 1542 if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) { 1543 error("%s: open(\"/dev/null\"): %s", __func__, 1544 strerror(errno)); 1545 } else { 1546 keep_stderr = log_is_on_stderr() && debug_flag; 1547 if (dup2(devnull, STDIN_FILENO) == -1 || 1548 dup2(devnull, STDOUT_FILENO) == -1 || 1549 (!keep_stderr && dup2(devnull, STDERR_FILENO) == -1)) 1550 error("%s: dup2: %s", __func__, strerror(errno)); 1551 if (devnull > STDERR_FILENO) 1552 close(devnull); 1553 } 1554 daemon(1, 1); 1555 setproctitle("%s [mux]", options.control_path); 1556 } 1557 1558 /* Do fork() after authentication. Used by "ssh -f" */ 1559 static void 1560 fork_postauth(void) 1561 { 1562 if (need_controlpersist_detach) 1563 control_persist_detach(); 1564 debug("forking to background"); 1565 fork_after_authentication_flag = 0; 1566 if (daemon(1, 1) < 0) 1567 fatal("daemon() failed: %.200s", strerror(errno)); 1568 } 1569 1570 /* Callback for remote forward global requests */ 1571 static void 1572 ssh_confirm_remote_forward(struct ssh *ssh, int type, u_int32_t seq, void *ctxt) 1573 { 1574 struct Forward *rfwd = (struct Forward *)ctxt; 1575 1576 /* XXX verbose() on failure? */ 1577 debug("remote forward %s for: listen %s%s%d, connect %s:%d", 1578 type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure", 1579 rfwd->listen_path ? rfwd->listen_path : 1580 rfwd->listen_host ? rfwd->listen_host : "", 1581 (rfwd->listen_path || rfwd->listen_host) ? ":" : "", 1582 rfwd->listen_port, rfwd->connect_path ? rfwd->connect_path : 1583 rfwd->connect_host, rfwd->connect_port); 1584 if (rfwd->listen_path == NULL && rfwd->listen_port == 0) { 1585 if (type == SSH2_MSG_REQUEST_SUCCESS) { 1586 rfwd->allocated_port = packet_get_int(); 1587 logit("Allocated port %u for remote forward to %s:%d", 1588 rfwd->allocated_port, 1589 rfwd->connect_host, rfwd->connect_port); 1590 channel_update_permitted_opens(ssh, 1591 rfwd->handle, rfwd->allocated_port); 1592 } else { 1593 channel_update_permitted_opens(ssh, rfwd->handle, -1); 1594 } 1595 } 1596 1597 if (type == SSH2_MSG_REQUEST_FAILURE) { 1598 if (options.exit_on_forward_failure) { 1599 if (rfwd->listen_path != NULL) 1600 fatal("Error: remote port forwarding failed " 1601 "for listen path %s", rfwd->listen_path); 1602 else 1603 fatal("Error: remote port forwarding failed " 1604 "for listen port %d", rfwd->listen_port); 1605 } else { 1606 if (rfwd->listen_path != NULL) 1607 logit("Warning: remote port forwarding failed " 1608 "for listen path %s", rfwd->listen_path); 1609 else 1610 logit("Warning: remote port forwarding failed " 1611 "for listen port %d", rfwd->listen_port); 1612 } 1613 } 1614 if (++remote_forward_confirms_received == options.num_remote_forwards) { 1615 debug("All remote forwarding requests processed"); 1616 if (fork_after_authentication_flag) 1617 fork_postauth(); 1618 } 1619 } 1620 1621 static void 1622 client_cleanup_stdio_fwd(struct ssh *ssh, int id, void *arg) 1623 { 1624 debug("stdio forwarding: done"); 1625 cleanup_exit(0); 1626 } 1627 1628 static void 1629 ssh_stdio_confirm(struct ssh *ssh, int id, int success, void *arg) 1630 { 1631 if (!success) 1632 fatal("stdio forwarding failed"); 1633 } 1634 1635 static void 1636 ssh_init_stdio_forwarding(struct ssh *ssh) 1637 { 1638 Channel *c; 1639 int in, out; 1640 1641 if (options.stdio_forward_host == NULL) 1642 return; 1643 1644 debug3("%s: %s:%d", __func__, options.stdio_forward_host, 1645 options.stdio_forward_port); 1646 1647 if ((in = dup(STDIN_FILENO)) < 0 || 1648 (out = dup(STDOUT_FILENO)) < 0) 1649 fatal("channel_connect_stdio_fwd: dup() in/out failed"); 1650 if ((c = channel_connect_stdio_fwd(ssh, options.stdio_forward_host, 1651 options.stdio_forward_port, in, out)) == NULL) 1652 fatal("%s: channel_connect_stdio_fwd failed", __func__); 1653 channel_register_cleanup(ssh, c->self, client_cleanup_stdio_fwd, 0); 1654 channel_register_open_confirm(ssh, c->self, ssh_stdio_confirm, NULL); 1655 } 1656 1657 static void 1658 ssh_init_forwarding(struct ssh *ssh, char **ifname) 1659 { 1660 int success = 0; 1661 int i; 1662 1663 /* Initiate local TCP/IP port forwardings. */ 1664 for (i = 0; i < options.num_local_forwards; i++) { 1665 debug("Local connections to %.200s:%d forwarded to remote " 1666 "address %.200s:%d", 1667 (options.local_forwards[i].listen_path != NULL) ? 1668 options.local_forwards[i].listen_path : 1669 (options.local_forwards[i].listen_host == NULL) ? 1670 (options.fwd_opts.gateway_ports ? "*" : "LOCALHOST") : 1671 options.local_forwards[i].listen_host, 1672 options.local_forwards[i].listen_port, 1673 (options.local_forwards[i].connect_path != NULL) ? 1674 options.local_forwards[i].connect_path : 1675 options.local_forwards[i].connect_host, 1676 options.local_forwards[i].connect_port); 1677 success += channel_setup_local_fwd_listener(ssh, 1678 &options.local_forwards[i], &options.fwd_opts); 1679 } 1680 if (i > 0 && success != i && options.exit_on_forward_failure) 1681 fatal("Could not request local forwarding."); 1682 if (i > 0 && success == 0) 1683 error("Could not request local forwarding."); 1684 1685 /* Initiate remote TCP/IP port forwardings. */ 1686 for (i = 0; i < options.num_remote_forwards; i++) { 1687 debug("Remote connections from %.200s:%d forwarded to " 1688 "local address %.200s:%d", 1689 (options.remote_forwards[i].listen_path != NULL) ? 1690 options.remote_forwards[i].listen_path : 1691 (options.remote_forwards[i].listen_host == NULL) ? 1692 "LOCALHOST" : options.remote_forwards[i].listen_host, 1693 options.remote_forwards[i].listen_port, 1694 (options.remote_forwards[i].connect_path != NULL) ? 1695 options.remote_forwards[i].connect_path : 1696 options.remote_forwards[i].connect_host, 1697 options.remote_forwards[i].connect_port); 1698 options.remote_forwards[i].handle = 1699 channel_request_remote_forwarding(ssh, 1700 &options.remote_forwards[i]); 1701 if (options.remote_forwards[i].handle < 0) { 1702 if (options.exit_on_forward_failure) 1703 fatal("Could not request remote forwarding."); 1704 else 1705 logit("Warning: Could not request remote " 1706 "forwarding."); 1707 } else { 1708 client_register_global_confirm( 1709 ssh_confirm_remote_forward, 1710 &options.remote_forwards[i]); 1711 } 1712 } 1713 1714 /* Initiate tunnel forwarding. */ 1715 if (options.tun_open != SSH_TUNMODE_NO) { 1716 if ((*ifname = client_request_tun_fwd(ssh, 1717 options.tun_open, options.tun_local, 1718 options.tun_remote)) == NULL) { 1719 if (options.exit_on_forward_failure) 1720 fatal("Could not request tunnel forwarding."); 1721 else 1722 error("Could not request tunnel forwarding."); 1723 } 1724 } 1725 } 1726 1727 static void 1728 check_agent_present(void) 1729 { 1730 int r; 1731 1732 if (options.forward_agent) { 1733 /* Clear agent forwarding if we don't have an agent. */ 1734 if ((r = ssh_get_authentication_socket(NULL)) != 0) { 1735 options.forward_agent = 0; 1736 if (r != SSH_ERR_AGENT_NOT_PRESENT) 1737 debug("ssh_get_authentication_socket: %s", 1738 ssh_err(r)); 1739 } 1740 } 1741 } 1742 1743 static void 1744 ssh_session2_setup(struct ssh *ssh, int id, int success, void *arg) 1745 { 1746 extern char **environ; 1747 const char *display; 1748 int interactive = tty_flag; 1749 char *proto = NULL, *data = NULL; 1750 1751 if (!success) 1752 return; /* No need for error message, channels code sens one */ 1753 1754 display = getenv("DISPLAY"); 1755 if (display == NULL && options.forward_x11) 1756 debug("X11 forwarding requested but DISPLAY not set"); 1757 if (options.forward_x11 && client_x11_get_proto(ssh, display, 1758 options.xauth_location, options.forward_x11_trusted, 1759 options.forward_x11_timeout, &proto, &data) == 0) { 1760 /* Request forwarding with authentication spoofing. */ 1761 debug("Requesting X11 forwarding with authentication " 1762 "spoofing."); 1763 x11_request_forwarding_with_spoofing(ssh, id, display, proto, 1764 data, 1); 1765 client_expect_confirm(ssh, id, "X11 forwarding", CONFIRM_WARN); 1766 /* XXX exit_on_forward_failure */ 1767 interactive = 1; 1768 } 1769 1770 check_agent_present(); 1771 if (options.forward_agent) { 1772 debug("Requesting authentication agent forwarding."); 1773 channel_request_start(ssh, id, "auth-agent-req@openssh.com", 0); 1774 packet_send(); 1775 } 1776 1777 /* Tell the packet module whether this is an interactive session. */ 1778 packet_set_interactive(interactive, 1779 options.ip_qos_interactive, options.ip_qos_bulk); 1780 1781 client_session2_setup(ssh, id, tty_flag, subsystem_flag, getenv("TERM"), 1782 NULL, fileno(stdin), &command, environ); 1783 } 1784 1785 /* open new channel for a session */ 1786 static int 1787 ssh_session2_open(struct ssh *ssh) 1788 { 1789 Channel *c; 1790 int window, packetmax, in, out, err; 1791 1792 if (stdin_null_flag) { 1793 in = open(_PATH_DEVNULL, O_RDONLY); 1794 } else { 1795 in = dup(STDIN_FILENO); 1796 } 1797 out = dup(STDOUT_FILENO); 1798 err = dup(STDERR_FILENO); 1799 1800 if (in < 0 || out < 0 || err < 0) 1801 fatal("dup() in/out/err failed"); 1802 1803 /* enable nonblocking unless tty */ 1804 if (!isatty(in)) 1805 set_nonblock(in); 1806 if (!isatty(out)) 1807 set_nonblock(out); 1808 if (!isatty(err)) 1809 set_nonblock(err); 1810 1811 window = CHAN_SES_WINDOW_DEFAULT; 1812 packetmax = CHAN_SES_PACKET_DEFAULT; 1813 if (tty_flag) { 1814 window >>= 1; 1815 packetmax >>= 1; 1816 } 1817 c = channel_new(ssh, 1818 "session", SSH_CHANNEL_OPENING, in, out, err, 1819 window, packetmax, CHAN_EXTENDED_WRITE, 1820 "client-session", /*nonblock*/0); 1821 1822 debug3("%s: channel_new: %d", __func__, c->self); 1823 1824 channel_send_open(ssh, c->self); 1825 if (!no_shell_flag) 1826 channel_register_open_confirm(ssh, c->self, 1827 ssh_session2_setup, NULL); 1828 1829 return c->self; 1830 } 1831 1832 static int 1833 ssh_session2(struct ssh *ssh, struct passwd *pw) 1834 { 1835 int devnull, id = -1; 1836 char *cp, *tun_fwd_ifname = NULL; 1837 1838 /* XXX should be pre-session */ 1839 if (!options.control_persist) 1840 ssh_init_stdio_forwarding(ssh); 1841 1842 ssh_init_forwarding(ssh, &tun_fwd_ifname); 1843 1844 if (options.local_command != NULL) { 1845 debug3("expanding LocalCommand: %s", options.local_command); 1846 cp = options.local_command; 1847 options.local_command = percent_expand(cp, 1848 "C", conn_hash_hex, 1849 "L", shorthost, 1850 "d", pw->pw_dir, 1851 "h", host, 1852 "l", thishost, 1853 "n", host_arg, 1854 "p", portstr, 1855 "r", options.user, 1856 "u", pw->pw_name, 1857 "T", tun_fwd_ifname == NULL ? "NONE" : tun_fwd_ifname, 1858 (char *)NULL); 1859 debug3("expanded LocalCommand: %s", options.local_command); 1860 free(cp); 1861 } 1862 1863 /* Start listening for multiplex clients */ 1864 if (!packet_get_mux()) 1865 muxserver_listen(ssh); 1866 1867 /* 1868 * If we are in control persist mode and have a working mux listen 1869 * socket, then prepare to background ourselves and have a foreground 1870 * client attach as a control slave. 1871 * NB. we must save copies of the flags that we override for 1872 * the backgrounding, since we defer attachment of the slave until 1873 * after the connection is fully established (in particular, 1874 * async rfwd replies have been received for ExitOnForwardFailure). 1875 */ 1876 if (options.control_persist && muxserver_sock != -1) { 1877 ostdin_null_flag = stdin_null_flag; 1878 ono_shell_flag = no_shell_flag; 1879 orequest_tty = options.request_tty; 1880 otty_flag = tty_flag; 1881 stdin_null_flag = 1; 1882 no_shell_flag = 1; 1883 tty_flag = 0; 1884 if (!fork_after_authentication_flag) 1885 need_controlpersist_detach = 1; 1886 fork_after_authentication_flag = 1; 1887 } 1888 /* 1889 * ControlPersist mux listen socket setup failed, attempt the 1890 * stdio forward setup that we skipped earlier. 1891 */ 1892 if (options.control_persist && muxserver_sock == -1) 1893 ssh_init_stdio_forwarding(ssh); 1894 1895 if (!no_shell_flag) 1896 id = ssh_session2_open(ssh); 1897 else { 1898 packet_set_interactive( 1899 options.control_master == SSHCTL_MASTER_NO, 1900 options.ip_qos_interactive, options.ip_qos_bulk); 1901 } 1902 1903 /* If we don't expect to open a new session, then disallow it */ 1904 if (options.control_master == SSHCTL_MASTER_NO && 1905 (datafellows & SSH_NEW_OPENSSH)) { 1906 debug("Requesting no-more-sessions@openssh.com"); 1907 packet_start(SSH2_MSG_GLOBAL_REQUEST); 1908 packet_put_cstring("no-more-sessions@openssh.com"); 1909 packet_put_char(0); 1910 packet_send(); 1911 } 1912 1913 /* Execute a local command */ 1914 if (options.local_command != NULL && 1915 options.permit_local_command) 1916 ssh_local_cmd(options.local_command); 1917 1918 /* 1919 * stdout is now owned by the session channel; clobber it here 1920 * so future channel closes are propagated to the local fd. 1921 * NB. this can only happen after LocalCommand has completed, 1922 * as it may want to write to stdout. 1923 */ 1924 if (!need_controlpersist_detach) { 1925 if ((devnull = open(_PATH_DEVNULL, O_WRONLY)) == -1) 1926 error("%s: open %s: %s", __func__, 1927 _PATH_DEVNULL, strerror(errno)); 1928 if (dup2(devnull, STDOUT_FILENO) < 0) 1929 fatal("%s: dup2() stdout failed", __func__); 1930 if (devnull > STDERR_FILENO) 1931 close(devnull); 1932 } 1933 1934 /* 1935 * If requested and we are not interested in replies to remote 1936 * forwarding requests, then let ssh continue in the background. 1937 */ 1938 if (fork_after_authentication_flag) { 1939 if (options.exit_on_forward_failure && 1940 options.num_remote_forwards > 0) { 1941 debug("deferring postauth fork until remote forward " 1942 "confirmation received"); 1943 } else 1944 fork_postauth(); 1945 } 1946 1947 return client_loop(ssh, tty_flag, tty_flag ? 1948 options.escape_char : SSH_ESCAPECHAR_NONE, id); 1949 } 1950 1951 /* Loads all IdentityFile and CertificateFile keys */ 1952 static void 1953 load_public_identity_files(struct passwd *pw) 1954 { 1955 char *filename, *cp; 1956 struct sshkey *public; 1957 int i; 1958 u_int n_ids, n_certs; 1959 char *identity_files[SSH_MAX_IDENTITY_FILES]; 1960 struct sshkey *identity_keys[SSH_MAX_IDENTITY_FILES]; 1961 char *certificate_files[SSH_MAX_CERTIFICATE_FILES]; 1962 struct sshkey *certificates[SSH_MAX_CERTIFICATE_FILES]; 1963 #ifdef ENABLE_PKCS11 1964 struct sshkey **keys; 1965 int nkeys; 1966 #endif /* PKCS11 */ 1967 1968 n_ids = n_certs = 0; 1969 memset(identity_files, 0, sizeof(identity_files)); 1970 memset(identity_keys, 0, sizeof(identity_keys)); 1971 memset(certificate_files, 0, sizeof(certificate_files)); 1972 memset(certificates, 0, sizeof(certificates)); 1973 1974 #ifdef ENABLE_PKCS11 1975 if (options.pkcs11_provider != NULL && 1976 options.num_identity_files < SSH_MAX_IDENTITY_FILES && 1977 (pkcs11_init(!options.batch_mode) == 0) && 1978 (nkeys = pkcs11_add_provider(options.pkcs11_provider, NULL, 1979 &keys)) > 0) { 1980 for (i = 0; i < nkeys; i++) { 1981 if (n_ids >= SSH_MAX_IDENTITY_FILES) { 1982 key_free(keys[i]); 1983 continue; 1984 } 1985 identity_keys[n_ids] = keys[i]; 1986 identity_files[n_ids] = 1987 xstrdup(options.pkcs11_provider); /* XXX */ 1988 n_ids++; 1989 } 1990 free(keys); 1991 } 1992 #endif /* ENABLE_PKCS11 */ 1993 if ((pw = getpwuid(original_real_uid)) == NULL) 1994 fatal("load_public_identity_files: getpwuid failed"); 1995 for (i = 0; i < options.num_identity_files; i++) { 1996 if (n_ids >= SSH_MAX_IDENTITY_FILES || 1997 strcasecmp(options.identity_files[i], "none") == 0) { 1998 free(options.identity_files[i]); 1999 options.identity_files[i] = NULL; 2000 continue; 2001 } 2002 cp = tilde_expand_filename(options.identity_files[i], 2003 original_real_uid); 2004 filename = percent_expand(cp, "d", pw->pw_dir, 2005 "u", pw->pw_name, "l", thishost, "h", host, 2006 "r", options.user, (char *)NULL); 2007 free(cp); 2008 public = key_load_public(filename, NULL); 2009 debug("identity file %s type %d", filename, 2010 public ? public->type : -1); 2011 free(options.identity_files[i]); 2012 identity_files[n_ids] = filename; 2013 identity_keys[n_ids] = public; 2014 2015 if (++n_ids >= SSH_MAX_IDENTITY_FILES) 2016 continue; 2017 2018 /* 2019 * If no certificates have been explicitly listed then try 2020 * to add the default certificate variant too. 2021 */ 2022 if (options.num_certificate_files != 0) 2023 continue; 2024 xasprintf(&cp, "%s-cert", filename); 2025 public = key_load_public(cp, NULL); 2026 debug("identity file %s type %d", cp, 2027 public ? public->type : -1); 2028 if (public == NULL) { 2029 free(cp); 2030 continue; 2031 } 2032 if (!key_is_cert(public)) { 2033 debug("%s: key %s type %s is not a certificate", 2034 __func__, cp, key_type(public)); 2035 key_free(public); 2036 free(cp); 2037 continue; 2038 } 2039 /* NB. leave filename pointing to private key */ 2040 identity_files[n_ids] = xstrdup(filename); 2041 identity_keys[n_ids] = public; 2042 n_ids++; 2043 } 2044 2045 if (options.num_certificate_files > SSH_MAX_CERTIFICATE_FILES) 2046 fatal("%s: too many certificates", __func__); 2047 for (i = 0; i < options.num_certificate_files; i++) { 2048 cp = tilde_expand_filename(options.certificate_files[i], 2049 original_real_uid); 2050 filename = percent_expand(cp, "d", pw->pw_dir, 2051 "u", pw->pw_name, "l", thishost, "h", host, 2052 "r", options.user, (char *)NULL); 2053 free(cp); 2054 2055 public = key_load_public(filename, NULL); 2056 debug("certificate file %s type %d", filename, 2057 public ? public->type : -1); 2058 free(options.certificate_files[i]); 2059 options.certificate_files[i] = NULL; 2060 if (public == NULL) { 2061 free(filename); 2062 continue; 2063 } 2064 if (!key_is_cert(public)) { 2065 debug("%s: key %s type %s is not a certificate", 2066 __func__, filename, key_type(public)); 2067 key_free(public); 2068 free(filename); 2069 continue; 2070 } 2071 certificate_files[n_certs] = filename; 2072 certificates[n_certs] = public; 2073 ++n_certs; 2074 } 2075 2076 options.num_identity_files = n_ids; 2077 memcpy(options.identity_files, identity_files, sizeof(identity_files)); 2078 memcpy(options.identity_keys, identity_keys, sizeof(identity_keys)); 2079 2080 options.num_certificate_files = n_certs; 2081 memcpy(options.certificate_files, 2082 certificate_files, sizeof(certificate_files)); 2083 memcpy(options.certificates, certificates, sizeof(certificates)); 2084 } 2085 2086 static void 2087 main_sigchld_handler(int sig) 2088 { 2089 int save_errno = errno; 2090 pid_t pid; 2091 int status; 2092 2093 while ((pid = waitpid(-1, &status, WNOHANG)) > 0 || 2094 (pid < 0 && errno == EINTR)) 2095 ; 2096 errno = save_errno; 2097 } 2098