1/* $OpenBSD: ssh.c,v 1.494 2018/10/03 06:38:35 djm Exp $ */ 2/* 3 * Author: Tatu Ylonen <ylo@cs.hut.fi> 4 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 5 * All rights reserved 6 * Ssh client program. This program can be used to log into a remote machine. 7 * The software supports strong authentication, encryption, and forwarding 8 * of X11, TCP/IP, and authentication connections. 9 * 10 * As far as I am concerned, the code I have written for this software 11 * can be used freely for any purpose. Any derived versions of this 12 * software must be clearly marked as such, and if the derived work is 13 * incompatible with the protocol description in the RFC file, it must be 14 * called by a name other than "ssh" or "Secure Shell". 15 * 16 * Copyright (c) 1999 Niels Provos. All rights reserved. 17 * Copyright (c) 2000, 2001, 2002, 2003 Markus Friedl. All rights reserved. 18 * 19 * Modified to work with SSL by Niels Provos <provos@citi.umich.edu> 20 * in Canada (German citizen). 21 * 22 * Redistribution and use in source and binary forms, with or without 23 * modification, are permitted provided that the following conditions 24 * are met: 25 * 1. Redistributions of source code must retain the above copyright 26 * notice, this list of conditions and the following disclaimer. 27 * 2. Redistributions in binary form must reproduce the above copyright 28 * notice, this list of conditions and the following disclaimer in the 29 * documentation and/or other materials provided with the distribution. 30 * 31 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 32 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 33 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 34 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 35 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 36 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 37 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 38 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 39 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 40 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 41 */ 42 43#include "includes.h" 44__RCSID("$FreeBSD$"); 45 46#include <sys/types.h> 47#ifdef HAVE_SYS_STAT_H 48# include <sys/stat.h> 49#endif 50#include <sys/resource.h> 51#include <sys/ioctl.h> 52#include <sys/socket.h> 53#include <sys/wait.h> 54 55#include <ctype.h> 56#include <errno.h> 57#include <fcntl.h> 58#include <netdb.h> 59#ifdef HAVE_PATHS_H 60#include <paths.h> 61#endif 62#include <pwd.h> 63#include <signal.h> 64#include <stdarg.h> 65#include <stddef.h> 66#include <stdio.h> 67#include <stdlib.h> 68#include <string.h> 69#include <unistd.h> 70#include <limits.h> 71#include <locale.h> 72 73#include <netinet/in.h> 74#include <arpa/inet.h> 75 76#ifdef WITH_OPENSSL 77#include <openssl/evp.h> 78#include <openssl/err.h> 79#endif 80#include "openbsd-compat/openssl-compat.h" 81#include "openbsd-compat/sys-queue.h" 82 83#include "xmalloc.h" 84#include "ssh.h" 85#include "ssh2.h" 86#include "canohost.h" 87#include "compat.h" 88#include "cipher.h" 89#include "digest.h" 90#include "packet.h" 91#include "sshbuf.h" 92#include "channels.h" 93#include "sshkey.h" 94#include "authfd.h" 95#include "authfile.h" 96#include "pathnames.h" 97#include "dispatch.h" 98#include "clientloop.h" 99#include "log.h" 100#include "misc.h" 101#include "readconf.h" 102#include "sshconnect.h" 103#include "kex.h" 104#include "mac.h" 105#include "sshpty.h" 106#include "match.h" 107#include "msg.h" 108#include "version.h" 109#include "ssherr.h" 110#include "myproposal.h" 111#include "utf8.h" 112 113#ifdef ENABLE_PKCS11 114#include "ssh-pkcs11.h" 115#endif 116 117extern char *__progname; 118 119/* Saves a copy of argv for setproctitle emulation */ 120#ifndef HAVE_SETPROCTITLE 121static char **saved_av; 122#endif 123 124/* Flag indicating whether debug mode is on. May be set on the command line. */ 125int debug_flag = 0; 126 127/* Flag indicating whether a tty should be requested */ 128int tty_flag = 0; 129 130/* don't exec a shell */ 131int no_shell_flag = 0; 132 133/* 134 * Flag indicating that nothing should be read from stdin. This can be set 135 * on the command line. 136 */ 137int stdin_null_flag = 0; 138 139/* 140 * Flag indicating that the current process should be backgrounded and 141 * a new slave launched in the foreground for ControlPersist. 142 */ 143int need_controlpersist_detach = 0; 144 145/* Copies of flags for ControlPersist foreground slave */ 146int ostdin_null_flag, ono_shell_flag, otty_flag, orequest_tty; 147 148/* 149 * Flag indicating that ssh should fork after authentication. This is useful 150 * so that the passphrase can be entered manually, and then ssh goes to the 151 * background. 152 */ 153int fork_after_authentication_flag = 0; 154 155/* 156 * General data structure for command line options and options configurable 157 * in configuration files. See readconf.h. 158 */ 159Options options; 160 161/* optional user configfile */ 162char *config = NULL; 163 164/* 165 * Name of the host we are connecting to. This is the name given on the 166 * command line, or the HostName specified for the user-supplied name in a 167 * configuration file. 168 */ 169char *host; 170 171/* Various strings used to to percent_expand() arguments */ 172static char thishost[NI_MAXHOST], shorthost[NI_MAXHOST], portstr[NI_MAXSERV]; 173static char uidstr[32], *host_arg, *conn_hash_hex; 174 175/* socket address the host resolves to */ 176struct sockaddr_storage hostaddr; 177 178/* Private host keys. */ 179Sensitive sensitive_data; 180 181/* command to be executed */ 182struct sshbuf *command; 183 184/* Should we execute a command or invoke a subsystem? */ 185int subsystem_flag = 0; 186 187/* # of replies received for global requests */ 188static int remote_forward_confirms_received = 0; 189 190/* mux.c */ 191extern int muxserver_sock; 192extern u_int muxclient_command; 193 194/* Prints a help message to the user. This function never returns. */ 195 196static void 197usage(void) 198{ 199 fprintf(stderr, 200"usage: ssh [-46AaCfGgKkMNnqsTtVvXxYy] [-B bind_interface]\n" 201" [-b bind_address] [-c cipher_spec] [-D [bind_address:]port]\n" 202" [-E log_file] [-e escape_char] [-F configfile] [-I pkcs11]\n" 203" [-i identity_file] [-J [user@]host[:port]] [-L address]\n" 204" [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n" 205" [-Q query_option] [-R address] [-S ctl_path] [-W host:port]\n" 206" [-w local_tun[:remote_tun]] destination [command]\n" 207 ); 208 exit(255); 209} 210 211static int ssh_session2(struct ssh *, struct passwd *); 212static void load_public_identity_files(struct passwd *); 213static void main_sigchld_handler(int); 214 215/* ~/ expand a list of paths. NB. assumes path[n] is heap-allocated. */ 216static void 217tilde_expand_paths(char **paths, u_int num_paths) 218{ 219 u_int i; 220 char *cp; 221 222 for (i = 0; i < num_paths; i++) { 223 cp = tilde_expand_filename(paths[i], getuid()); 224 free(paths[i]); 225 paths[i] = cp; 226 } 227} 228 229/* 230 * Attempt to resolve a host name / port to a set of addresses and 231 * optionally return any CNAMEs encountered along the way. 232 * Returns NULL on failure. 233 * NB. this function must operate with a options having undefined members. 234 */ 235static struct addrinfo * 236resolve_host(const char *name, int port, int logerr, char *cname, size_t clen) 237{ 238 char strport[NI_MAXSERV]; 239 struct addrinfo hints, *res; 240 int gaierr, loglevel = SYSLOG_LEVEL_DEBUG1; 241 242 if (port <= 0) 243 port = default_ssh_port(); 244 245 snprintf(strport, sizeof strport, "%d", port); 246 memset(&hints, 0, sizeof(hints)); 247 hints.ai_family = options.address_family == -1 ? 248 AF_UNSPEC : options.address_family; 249 hints.ai_socktype = SOCK_STREAM; 250 if (cname != NULL) 251 hints.ai_flags = AI_CANONNAME; 252 if ((gaierr = getaddrinfo(name, strport, &hints, &res)) != 0) { 253 if (logerr || (gaierr != EAI_NONAME && gaierr != EAI_NODATA)) 254 loglevel = SYSLOG_LEVEL_ERROR; 255 do_log2(loglevel, "%s: Could not resolve hostname %.100s: %s", 256 __progname, name, ssh_gai_strerror(gaierr)); 257 return NULL; 258 } 259 if (cname != NULL && res->ai_canonname != NULL) { 260 if (strlcpy(cname, res->ai_canonname, clen) >= clen) { 261 error("%s: host \"%s\" cname \"%s\" too long (max %lu)", 262 __func__, name, res->ai_canonname, (u_long)clen); 263 if (clen > 0) 264 *cname = '\0'; 265 } 266 } 267 return res; 268} 269 270/* Returns non-zero if name can only be an address and not a hostname */ 271static int 272is_addr_fast(const char *name) 273{ 274 return (strchr(name, '%') != NULL || strchr(name, ':') != NULL || 275 strspn(name, "0123456789.") == strlen(name)); 276} 277 278/* Returns non-zero if name represents a valid, single address */ 279static int 280is_addr(const char *name) 281{ 282 char strport[NI_MAXSERV]; 283 struct addrinfo hints, *res; 284 285 if (is_addr_fast(name)) 286 return 1; 287 288 snprintf(strport, sizeof strport, "%u", default_ssh_port()); 289 memset(&hints, 0, sizeof(hints)); 290 hints.ai_family = options.address_family == -1 ? 291 AF_UNSPEC : options.address_family; 292 hints.ai_socktype = SOCK_STREAM; 293 hints.ai_flags = AI_NUMERICHOST|AI_NUMERICSERV; 294 if (getaddrinfo(name, strport, &hints, &res) != 0) 295 return 0; 296 if (res == NULL || res->ai_next != NULL) { 297 freeaddrinfo(res); 298 return 0; 299 } 300 freeaddrinfo(res); 301 return 1; 302} 303 304/* 305 * Attempt to resolve a numeric host address / port to a single address. 306 * Returns a canonical address string. 307 * Returns NULL on failure. 308 * NB. this function must operate with a options having undefined members. 309 */ 310static struct addrinfo * 311resolve_addr(const char *name, int port, char *caddr, size_t clen) 312{ 313 char addr[NI_MAXHOST], strport[NI_MAXSERV]; 314 struct addrinfo hints, *res; 315 int gaierr; 316 317 if (port <= 0) 318 port = default_ssh_port(); 319 snprintf(strport, sizeof strport, "%u", port); 320 memset(&hints, 0, sizeof(hints)); 321 hints.ai_family = options.address_family == -1 ? 322 AF_UNSPEC : options.address_family; 323 hints.ai_socktype = SOCK_STREAM; 324 hints.ai_flags = AI_NUMERICHOST|AI_NUMERICSERV; 325 if ((gaierr = getaddrinfo(name, strport, &hints, &res)) != 0) { 326 debug2("%s: could not resolve name %.100s as address: %s", 327 __func__, name, ssh_gai_strerror(gaierr)); 328 return NULL; 329 } 330 if (res == NULL) { 331 debug("%s: getaddrinfo %.100s returned no addresses", 332 __func__, name); 333 return NULL; 334 } 335 if (res->ai_next != NULL) { 336 debug("%s: getaddrinfo %.100s returned multiple addresses", 337 __func__, name); 338 goto fail; 339 } 340 if ((gaierr = getnameinfo(res->ai_addr, res->ai_addrlen, 341 addr, sizeof(addr), NULL, 0, NI_NUMERICHOST)) != 0) { 342 debug("%s: Could not format address for name %.100s: %s", 343 __func__, name, ssh_gai_strerror(gaierr)); 344 goto fail; 345 } 346 if (strlcpy(caddr, addr, clen) >= clen) { 347 error("%s: host \"%s\" addr \"%s\" too long (max %lu)", 348 __func__, name, addr, (u_long)clen); 349 if (clen > 0) 350 *caddr = '\0'; 351 fail: 352 freeaddrinfo(res); 353 return NULL; 354 } 355 return res; 356} 357 358/* 359 * Check whether the cname is a permitted replacement for the hostname 360 * and perform the replacement if it is. 361 * NB. this function must operate with a options having undefined members. 362 */ 363static int 364check_follow_cname(int direct, char **namep, const char *cname) 365{ 366 int i; 367 struct allowed_cname *rule; 368 369 if (*cname == '\0' || options.num_permitted_cnames == 0 || 370 strcmp(*namep, cname) == 0) 371 return 0; 372 if (options.canonicalize_hostname == SSH_CANONICALISE_NO) 373 return 0; 374 /* 375 * Don't attempt to canonicalize names that will be interpreted by 376 * a proxy or jump host unless the user specifically requests so. 377 */ 378 if (!direct && 379 options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS) 380 return 0; 381 debug3("%s: check \"%s\" CNAME \"%s\"", __func__, *namep, cname); 382 for (i = 0; i < options.num_permitted_cnames; i++) { 383 rule = options.permitted_cnames + i; 384 if (match_pattern_list(*namep, rule->source_list, 1) != 1 || 385 match_pattern_list(cname, rule->target_list, 1) != 1) 386 continue; 387 verbose("Canonicalized DNS aliased hostname " 388 "\"%s\" => \"%s\"", *namep, cname); 389 free(*namep); 390 *namep = xstrdup(cname); 391 return 1; 392 } 393 return 0; 394} 395 396/* 397 * Attempt to resolve the supplied hostname after applying the user's 398 * canonicalization rules. Returns the address list for the host or NULL 399 * if no name was found after canonicalization. 400 * NB. this function must operate with a options having undefined members. 401 */ 402static struct addrinfo * 403resolve_canonicalize(char **hostp, int port) 404{ 405 int i, direct, ndots; 406 char *cp, *fullhost, newname[NI_MAXHOST]; 407 struct addrinfo *addrs; 408 409 /* 410 * Attempt to canonicalise addresses, regardless of 411 * whether hostname canonicalisation was requested 412 */ 413 if ((addrs = resolve_addr(*hostp, port, 414 newname, sizeof(newname))) != NULL) { 415 debug2("%s: hostname %.100s is address", __func__, *hostp); 416 if (strcasecmp(*hostp, newname) != 0) { 417 debug2("%s: canonicalised address \"%s\" => \"%s\"", 418 __func__, *hostp, newname); 419 free(*hostp); 420 *hostp = xstrdup(newname); 421 } 422 return addrs; 423 } 424 425 /* 426 * If this looks like an address but didn't parse as one, it might 427 * be an address with an invalid interface scope. Skip further 428 * attempts at canonicalisation. 429 */ 430 if (is_addr_fast(*hostp)) { 431 debug("%s: hostname %.100s is an unrecognised address", 432 __func__, *hostp); 433 return NULL; 434 } 435 436 if (options.canonicalize_hostname == SSH_CANONICALISE_NO) 437 return NULL; 438 439 /* 440 * Don't attempt to canonicalize names that will be interpreted by 441 * a proxy unless the user specifically requests so. 442 */ 443 direct = option_clear_or_none(options.proxy_command) && 444 options.jump_host == NULL; 445 if (!direct && 446 options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS) 447 return NULL; 448 449 /* If domain name is anchored, then resolve it now */ 450 if ((*hostp)[strlen(*hostp) - 1] == '.') { 451 debug3("%s: name is fully qualified", __func__); 452 fullhost = xstrdup(*hostp); 453 if ((addrs = resolve_host(fullhost, port, 0, 454 newname, sizeof(newname))) != NULL) 455 goto found; 456 free(fullhost); 457 goto notfound; 458 } 459 460 /* Don't apply canonicalization to sufficiently-qualified hostnames */ 461 ndots = 0; 462 for (cp = *hostp; *cp != '\0'; cp++) { 463 if (*cp == '.') 464 ndots++; 465 } 466 if (ndots > options.canonicalize_max_dots) { 467 debug3("%s: not canonicalizing hostname \"%s\" (max dots %d)", 468 __func__, *hostp, options.canonicalize_max_dots); 469 return NULL; 470 } 471 /* Attempt each supplied suffix */ 472 for (i = 0; i < options.num_canonical_domains; i++) { 473 *newname = '\0'; 474 xasprintf(&fullhost, "%s.%s.", *hostp, 475 options.canonical_domains[i]); 476 debug3("%s: attempting \"%s\" => \"%s\"", __func__, 477 *hostp, fullhost); 478 if ((addrs = resolve_host(fullhost, port, 0, 479 newname, sizeof(newname))) == NULL) { 480 free(fullhost); 481 continue; 482 } 483 found: 484 /* Remove trailing '.' */ 485 fullhost[strlen(fullhost) - 1] = '\0'; 486 /* Follow CNAME if requested */ 487 if (!check_follow_cname(direct, &fullhost, newname)) { 488 debug("Canonicalized hostname \"%s\" => \"%s\"", 489 *hostp, fullhost); 490 } 491 free(*hostp); 492 *hostp = fullhost; 493 return addrs; 494 } 495 notfound: 496 if (!options.canonicalize_fallback_local) 497 fatal("%s: Could not resolve host \"%s\"", __progname, *hostp); 498 debug2("%s: host %s not found in any suffix", __func__, *hostp); 499 return NULL; 500} 501 502/* 503 * Check the result of hostkey loading, ignoring some errors and 504 * fatal()ing for others. 505 */ 506static void 507check_load(int r, const char *path, const char *message) 508{ 509 switch (r) { 510 case 0: 511 break; 512 case SSH_ERR_INTERNAL_ERROR: 513 case SSH_ERR_ALLOC_FAIL: 514 fatal("load %s \"%s\": %s", message, path, ssh_err(r)); 515 case SSH_ERR_SYSTEM_ERROR: 516 /* Ignore missing files */ 517 if (errno == ENOENT) 518 break; 519 /* FALLTHROUGH */ 520 default: 521 error("load %s \"%s\": %s", message, path, ssh_err(r)); 522 break; 523 } 524} 525 526/* 527 * Read per-user configuration file. Ignore the system wide config 528 * file if the user specifies a config file on the command line. 529 */ 530static void 531process_config_files(const char *host_name, struct passwd *pw, int post_canon) 532{ 533 char buf[PATH_MAX]; 534 int r; 535 536 if (config != NULL) { 537 if (strcasecmp(config, "none") != 0 && 538 !read_config_file(config, pw, host, host_name, &options, 539 SSHCONF_USERCONF | (post_canon ? SSHCONF_POSTCANON : 0))) 540 fatal("Can't open user config file %.100s: " 541 "%.100s", config, strerror(errno)); 542 } else { 543 r = snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir, 544 _PATH_SSH_USER_CONFFILE); 545 if (r > 0 && (size_t)r < sizeof(buf)) 546 (void)read_config_file(buf, pw, host, host_name, 547 &options, SSHCONF_CHECKPERM | SSHCONF_USERCONF | 548 (post_canon ? SSHCONF_POSTCANON : 0)); 549 550 /* Read systemwide configuration file after user config. */ 551 (void)read_config_file(_PATH_HOST_CONFIG_FILE, pw, 552 host, host_name, &options, 553 post_canon ? SSHCONF_POSTCANON : 0); 554 } 555} 556 557/* Rewrite the port number in an addrinfo list of addresses */ 558static void 559set_addrinfo_port(struct addrinfo *addrs, int port) 560{ 561 struct addrinfo *addr; 562 563 for (addr = addrs; addr != NULL; addr = addr->ai_next) { 564 switch (addr->ai_family) { 565 case AF_INET: 566 ((struct sockaddr_in *)addr->ai_addr)-> 567 sin_port = htons(port); 568 break; 569 case AF_INET6: 570 ((struct sockaddr_in6 *)addr->ai_addr)-> 571 sin6_port = htons(port); 572 break; 573 } 574 } 575} 576 577/* 578 * Main program for the ssh client. 579 */ 580int 581main(int ac, char **av) 582{ 583 struct ssh *ssh = NULL; 584 int i, r, opt, exit_status, use_syslog, direct, timeout_ms; 585 int was_addr, config_test = 0, opt_terminated = 0; 586 char *p, *cp, *line, *argv0, buf[PATH_MAX], *logfile; 587 char cname[NI_MAXHOST]; 588 struct stat st; 589 struct passwd *pw; 590 extern int optind, optreset; 591 extern char *optarg; 592 struct Forward fwd; 593 struct addrinfo *addrs = NULL; 594 struct ssh_digest_ctx *md; 595 u_char conn_hash[SSH_DIGEST_MAX_LENGTH]; 596 597 ssh_malloc_init(); /* must be called before any mallocs */ 598 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ 599 sanitise_stdfd(); 600 601 __progname = ssh_get_progname(av[0]); 602 603#ifndef HAVE_SETPROCTITLE 604 /* Prepare for later setproctitle emulation */ 605 /* Save argv so it isn't clobbered by setproctitle() emulation */ 606 saved_av = xcalloc(ac + 1, sizeof(*saved_av)); 607 for (i = 0; i < ac; i++) 608 saved_av[i] = xstrdup(av[i]); 609 saved_av[i] = NULL; 610 compat_init_setproctitle(ac, av); 611 av = saved_av; 612#endif 613 614 /* 615 * Discard other fds that are hanging around. These can cause problem 616 * with backgrounded ssh processes started by ControlPersist. 617 */ 618 closefrom(STDERR_FILENO + 1); 619 620 /* Get user data. */ 621 pw = getpwuid(getuid()); 622 if (!pw) { 623 logit("No user exists for uid %lu", (u_long)getuid()); 624 exit(255); 625 } 626 /* Take a copy of the returned structure. */ 627 pw = pwcopy(pw); 628 629 /* 630 * Set our umask to something reasonable, as some files are created 631 * with the default umask. This will make them world-readable but 632 * writable only by the owner, which is ok for all files for which we 633 * don't set the modes explicitly. 634 */ 635 umask(022); 636 637 msetlocale(); 638 639 /* 640 * Initialize option structure to indicate that no values have been 641 * set. 642 */ 643 initialize_options(&options); 644 645 /* 646 * Prepare main ssh transport/connection structures 647 */ 648 if ((ssh = ssh_alloc_session_state()) == NULL) 649 fatal("Couldn't allocate session state"); 650 channel_init_channels(ssh); 651 active_state = ssh; /* XXX legacy API compat */ 652 653 /* Parse command-line arguments. */ 654 host = NULL; 655 use_syslog = 0; 656 logfile = NULL; 657 argv0 = av[0]; 658 659 again: 660 while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx" 661 "AB:CD:E:F:GI:J:KL:MNO:PQ:R:S:TVw:W:XYy")) != -1) { 662 switch (opt) { 663 case '1': 664 fatal("SSH protocol v.1 is no longer supported"); 665 break; 666 case '2': 667 /* Ignored */ 668 break; 669 case '4': 670 options.address_family = AF_INET; 671 break; 672 case '6': 673 options.address_family = AF_INET6; 674 break; 675 case 'n': 676 stdin_null_flag = 1; 677 break; 678 case 'f': 679 fork_after_authentication_flag = 1; 680 stdin_null_flag = 1; 681 break; 682 case 'x': 683 options.forward_x11 = 0; 684 break; 685 case 'X': 686 options.forward_x11 = 1; 687 break; 688 case 'y': 689 use_syslog = 1; 690 break; 691 case 'E': 692 logfile = optarg; 693 break; 694 case 'G': 695 config_test = 1; 696 break; 697 case 'Y': 698 options.forward_x11 = 1; 699 options.forward_x11_trusted = 1; 700 break; 701 case 'g': 702 options.fwd_opts.gateway_ports = 1; 703 break; 704 case 'O': 705 if (options.stdio_forward_host != NULL) 706 fatal("Cannot specify multiplexing " 707 "command with -W"); 708 else if (muxclient_command != 0) 709 fatal("Multiplexing command already specified"); 710 if (strcmp(optarg, "check") == 0) 711 muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK; 712 else if (strcmp(optarg, "forward") == 0) 713 muxclient_command = SSHMUX_COMMAND_FORWARD; 714 else if (strcmp(optarg, "exit") == 0) 715 muxclient_command = SSHMUX_COMMAND_TERMINATE; 716 else if (strcmp(optarg, "stop") == 0) 717 muxclient_command = SSHMUX_COMMAND_STOP; 718 else if (strcmp(optarg, "cancel") == 0) 719 muxclient_command = SSHMUX_COMMAND_CANCEL_FWD; 720 else if (strcmp(optarg, "proxy") == 0) 721 muxclient_command = SSHMUX_COMMAND_PROXY; 722 else 723 fatal("Invalid multiplex command."); 724 break; 725 case 'P': /* deprecated */ 726 break; 727 case 'Q': 728 cp = NULL; 729 if (strcmp(optarg, "cipher") == 0) 730 cp = cipher_alg_list('\n', 0); 731 else if (strcmp(optarg, "cipher-auth") == 0) 732 cp = cipher_alg_list('\n', 1); 733 else if (strcmp(optarg, "mac") == 0) 734 cp = mac_alg_list('\n'); 735 else if (strcmp(optarg, "kex") == 0) 736 cp = kex_alg_list('\n'); 737 else if (strcmp(optarg, "key") == 0) 738 cp = sshkey_alg_list(0, 0, 0, '\n'); 739 else if (strcmp(optarg, "key-cert") == 0) 740 cp = sshkey_alg_list(1, 0, 0, '\n'); 741 else if (strcmp(optarg, "key-plain") == 0) 742 cp = sshkey_alg_list(0, 1, 0, '\n'); 743 else if (strcmp(optarg, "sig") == 0) 744 cp = sshkey_alg_list(0, 1, 1, '\n'); 745 else if (strcmp(optarg, "protocol-version") == 0) 746 cp = xstrdup("2"); 747 else if (strcmp(optarg, "help") == 0) { 748 cp = xstrdup( 749 "cipher\ncipher-auth\nkex\nkey\n" 750 "key-cert\nkey-plain\nmac\n" 751 "protocol-version\nsig"); 752 } 753 if (cp == NULL) 754 fatal("Unsupported query \"%s\"", optarg); 755 printf("%s\n", cp); 756 free(cp); 757 exit(0); 758 break; 759 case 'a': 760 options.forward_agent = 0; 761 break; 762 case 'A': 763 options.forward_agent = 1; 764 break; 765 case 'k': 766 options.gss_deleg_creds = 0; 767 break; 768 case 'K': 769 options.gss_authentication = 1; 770 options.gss_deleg_creds = 1; 771 break; 772 case 'i': 773 p = tilde_expand_filename(optarg, getuid()); 774 if (stat(p, &st) < 0) 775 fprintf(stderr, "Warning: Identity file %s " 776 "not accessible: %s.\n", p, 777 strerror(errno)); 778 else 779 add_identity_file(&options, NULL, p, 1); 780 free(p); 781 break; 782 case 'I': 783#ifdef ENABLE_PKCS11 784 free(options.pkcs11_provider); 785 options.pkcs11_provider = xstrdup(optarg); 786#else 787 fprintf(stderr, "no support for PKCS#11.\n"); 788#endif 789 break; 790 case 'J': 791 if (options.jump_host != NULL) 792 fatal("Only a single -J option permitted"); 793 if (options.proxy_command != NULL) 794 fatal("Cannot specify -J with ProxyCommand"); 795 if (parse_jump(optarg, &options, 1) == -1) 796 fatal("Invalid -J argument"); 797 options.proxy_command = xstrdup("none"); 798 break; 799 case 't': 800 if (options.request_tty == REQUEST_TTY_YES) 801 options.request_tty = REQUEST_TTY_FORCE; 802 else 803 options.request_tty = REQUEST_TTY_YES; 804 break; 805 case 'v': 806 if (debug_flag == 0) { 807 debug_flag = 1; 808 options.log_level = SYSLOG_LEVEL_DEBUG1; 809 } else { 810 if (options.log_level < SYSLOG_LEVEL_DEBUG3) { 811 debug_flag++; 812 options.log_level++; 813 } 814 } 815 break; 816 case 'V': 817 if (options.version_addendum && 818 *options.version_addendum != '\0') 819 fprintf(stderr, "%s %s, %s\n", SSH_RELEASE, 820 options.version_addendum, 821 OPENSSL_VERSION_STRING); 822 else 823 fprintf(stderr, "%s, %s\n", SSH_RELEASE, 824 OPENSSL_VERSION_STRING); 825 if (opt == 'V') 826 exit(0); 827 break; 828 case 'w': 829 if (options.tun_open == -1) 830 options.tun_open = SSH_TUNMODE_DEFAULT; 831 options.tun_local = a2tun(optarg, &options.tun_remote); 832 if (options.tun_local == SSH_TUNID_ERR) { 833 fprintf(stderr, 834 "Bad tun device '%s'\n", optarg); 835 exit(255); 836 } 837 break; 838 case 'W': 839 if (options.stdio_forward_host != NULL) 840 fatal("stdio forward already specified"); 841 if (muxclient_command != 0) 842 fatal("Cannot specify stdio forward with -O"); 843 if (parse_forward(&fwd, optarg, 1, 0)) { 844 options.stdio_forward_host = fwd.listen_host; 845 options.stdio_forward_port = fwd.listen_port; 846 free(fwd.connect_host); 847 } else { 848 fprintf(stderr, 849 "Bad stdio forwarding specification '%s'\n", 850 optarg); 851 exit(255); 852 } 853 options.request_tty = REQUEST_TTY_NO; 854 no_shell_flag = 1; 855 break; 856 case 'q': 857 options.log_level = SYSLOG_LEVEL_QUIET; 858 break; 859 case 'e': 860 if (optarg[0] == '^' && optarg[2] == 0 && 861 (u_char) optarg[1] >= 64 && 862 (u_char) optarg[1] < 128) 863 options.escape_char = (u_char) optarg[1] & 31; 864 else if (strlen(optarg) == 1) 865 options.escape_char = (u_char) optarg[0]; 866 else if (strcmp(optarg, "none") == 0) 867 options.escape_char = SSH_ESCAPECHAR_NONE; 868 else { 869 fprintf(stderr, "Bad escape character '%s'.\n", 870 optarg); 871 exit(255); 872 } 873 break; 874 case 'c': 875 if (!ciphers_valid(*optarg == '+' ? 876 optarg + 1 : optarg)) { 877 fprintf(stderr, "Unknown cipher type '%s'\n", 878 optarg); 879 exit(255); 880 } 881 free(options.ciphers); 882 options.ciphers = xstrdup(optarg); 883 break; 884 case 'm': 885 if (mac_valid(optarg)) { 886 free(options.macs); 887 options.macs = xstrdup(optarg); 888 } else { 889 fprintf(stderr, "Unknown mac type '%s'\n", 890 optarg); 891 exit(255); 892 } 893 break; 894 case 'M': 895 if (options.control_master == SSHCTL_MASTER_YES) 896 options.control_master = SSHCTL_MASTER_ASK; 897 else 898 options.control_master = SSHCTL_MASTER_YES; 899 break; 900 case 'p': 901 if (options.port == -1) { 902 options.port = a2port(optarg); 903 if (options.port <= 0) { 904 fprintf(stderr, "Bad port '%s'\n", 905 optarg); 906 exit(255); 907 } 908 } 909 break; 910 case 'l': 911 if (options.user == NULL) 912 options.user = optarg; 913 break; 914 915 case 'L': 916 if (parse_forward(&fwd, optarg, 0, 0)) 917 add_local_forward(&options, &fwd); 918 else { 919 fprintf(stderr, 920 "Bad local forwarding specification '%s'\n", 921 optarg); 922 exit(255); 923 } 924 break; 925 926 case 'R': 927 if (parse_forward(&fwd, optarg, 0, 1) || 928 parse_forward(&fwd, optarg, 1, 1)) { 929 add_remote_forward(&options, &fwd); 930 } else { 931 fprintf(stderr, 932 "Bad remote forwarding specification " 933 "'%s'\n", optarg); 934 exit(255); 935 } 936 break; 937 938 case 'D': 939 if (parse_forward(&fwd, optarg, 1, 0)) { 940 add_local_forward(&options, &fwd); 941 } else { 942 fprintf(stderr, 943 "Bad dynamic forwarding specification " 944 "'%s'\n", optarg); 945 exit(255); 946 } 947 break; 948 949 case 'C': 950 options.compression = 1; 951 break; 952 case 'N': 953 no_shell_flag = 1; 954 options.request_tty = REQUEST_TTY_NO; 955 break; 956 case 'T': 957 options.request_tty = REQUEST_TTY_NO; 958 break; 959 case 'o': 960 line = xstrdup(optarg); 961 if (process_config_line(&options, pw, 962 host ? host : "", host ? host : "", line, 963 "command-line", 0, NULL, SSHCONF_USERCONF) != 0) 964 exit(255); 965 free(line); 966 break; 967 case 's': 968 subsystem_flag = 1; 969 break; 970 case 'S': 971 free(options.control_path); 972 options.control_path = xstrdup(optarg); 973 break; 974 case 'b': 975 options.bind_address = optarg; 976 break; 977 case 'B': 978 options.bind_interface = optarg; 979 break; 980 case 'F': 981 config = optarg; 982 break; 983 default: 984 usage(); 985 } 986 } 987 988 if (optind > 1 && strcmp(av[optind - 1], "--") == 0) 989 opt_terminated = 1; 990 991 ac -= optind; 992 av += optind; 993 994 if (ac > 0 && !host) { 995 int tport; 996 char *tuser; 997 switch (parse_ssh_uri(*av, &tuser, &host, &tport)) { 998 case -1: 999 usage(); 1000 break; 1001 case 0: 1002 if (options.user == NULL) { 1003 options.user = tuser; 1004 tuser = NULL; 1005 } 1006 free(tuser); 1007 if (options.port == -1 && tport != -1) 1008 options.port = tport; 1009 break; 1010 default: 1011 p = xstrdup(*av); 1012 cp = strrchr(p, '@'); 1013 if (cp != NULL) { 1014 if (cp == p) 1015 usage(); 1016 if (options.user == NULL) { 1017 options.user = p; 1018 p = NULL; 1019 } 1020 *cp++ = '\0'; 1021 host = xstrdup(cp); 1022 free(p); 1023 } else 1024 host = p; 1025 break; 1026 } 1027 if (ac > 1 && !opt_terminated) { 1028 optind = optreset = 1; 1029 goto again; 1030 } 1031 ac--, av++; 1032 } 1033 1034 /* Check that we got a host name. */ 1035 if (!host) 1036 usage(); 1037 1038 host_arg = xstrdup(host); 1039 1040#ifdef WITH_OPENSSL 1041 OpenSSL_add_all_algorithms(); 1042 ERR_load_crypto_strings(); 1043#endif 1044 1045 /* Initialize the command to execute on remote host. */ 1046 if ((command = sshbuf_new()) == NULL) 1047 fatal("sshbuf_new failed"); 1048 1049 /* 1050 * Save the command to execute on the remote host in a buffer. There 1051 * is no limit on the length of the command, except by the maximum 1052 * packet size. Also sets the tty flag if there is no command. 1053 */ 1054 if (!ac) { 1055 /* No command specified - execute shell on a tty. */ 1056 if (subsystem_flag) { 1057 fprintf(stderr, 1058 "You must specify a subsystem to invoke.\n"); 1059 usage(); 1060 } 1061 } else { 1062 /* A command has been specified. Store it into the buffer. */ 1063 for (i = 0; i < ac; i++) { 1064 if ((r = sshbuf_putf(command, "%s%s", 1065 i ? " " : "", av[i])) != 0) 1066 fatal("%s: buffer error: %s", 1067 __func__, ssh_err(r)); 1068 } 1069 } 1070 1071 /* 1072 * Initialize "log" output. Since we are the client all output 1073 * goes to stderr unless otherwise specified by -y or -E. 1074 */ 1075 if (use_syslog && logfile != NULL) 1076 fatal("Can't specify both -y and -E"); 1077 if (logfile != NULL) 1078 log_redirect_stderr_to(logfile); 1079 log_init(argv0, 1080 options.log_level == SYSLOG_LEVEL_NOT_SET ? 1081 SYSLOG_LEVEL_INFO : options.log_level, 1082 options.log_facility == SYSLOG_FACILITY_NOT_SET ? 1083 SYSLOG_FACILITY_USER : options.log_facility, 1084 !use_syslog); 1085 1086 if (debug_flag) 1087 /* version_addendum is always NULL at this point */ 1088 logit("%s, %s", SSH_RELEASE, OPENSSL_VERSION_STRING); 1089 1090 /* Parse the configuration files */ 1091 process_config_files(host_arg, pw, 0); 1092 1093 /* Hostname canonicalisation needs a few options filled. */ 1094 fill_default_options_for_canonicalization(&options); 1095 1096 /* If the user has replaced the hostname then take it into use now */ 1097 if (options.hostname != NULL) { 1098 /* NB. Please keep in sync with readconf.c:match_cfg_line() */ 1099 cp = percent_expand(options.hostname, 1100 "h", host, (char *)NULL); 1101 free(host); 1102 host = cp; 1103 free(options.hostname); 1104 options.hostname = xstrdup(host); 1105 } 1106 1107 /* Don't lowercase addresses, they will be explicitly canonicalised */ 1108 if ((was_addr = is_addr(host)) == 0) 1109 lowercase(host); 1110 1111 /* 1112 * Try to canonicalize if requested by configuration or the 1113 * hostname is an address. 1114 */ 1115 if (options.canonicalize_hostname != SSH_CANONICALISE_NO || was_addr) 1116 addrs = resolve_canonicalize(&host, options.port); 1117 1118 /* 1119 * If CanonicalizePermittedCNAMEs have been specified but 1120 * other canonicalization did not happen (by not being requested 1121 * or by failing with fallback) then the hostname may still be changed 1122 * as a result of CNAME following. 1123 * 1124 * Try to resolve the bare hostname name using the system resolver's 1125 * usual search rules and then apply the CNAME follow rules. 1126 * 1127 * Skip the lookup if a ProxyCommand is being used unless the user 1128 * has specifically requested canonicalisation for this case via 1129 * CanonicalizeHostname=always 1130 */ 1131 direct = option_clear_or_none(options.proxy_command) && 1132 options.jump_host == NULL; 1133 if (addrs == NULL && options.num_permitted_cnames != 0 && (direct || 1134 options.canonicalize_hostname == SSH_CANONICALISE_ALWAYS)) { 1135 if ((addrs = resolve_host(host, options.port, 1136 direct, cname, sizeof(cname))) == NULL) { 1137 /* Don't fatal proxied host names not in the DNS */ 1138 if (direct) 1139 cleanup_exit(255); /* logged in resolve_host */ 1140 } else 1141 check_follow_cname(direct, &host, cname); 1142 } 1143 1144 /* 1145 * If canonicalisation is enabled then re-parse the configuration 1146 * files as new stanzas may match. 1147 */ 1148 if (options.canonicalize_hostname != 0) { 1149 debug("Re-reading configuration after hostname " 1150 "canonicalisation"); 1151 free(options.hostname); 1152 options.hostname = xstrdup(host); 1153 process_config_files(host_arg, pw, 1); 1154 /* 1155 * Address resolution happens early with canonicalisation 1156 * enabled and the port number may have changed since, so 1157 * reset it in address list 1158 */ 1159 if (addrs != NULL && options.port > 0) 1160 set_addrinfo_port(addrs, options.port); 1161 } 1162 1163 /* Fill configuration defaults. */ 1164 fill_default_options(&options); 1165 1166 /* 1167 * If ProxyJump option specified, then construct a ProxyCommand now. 1168 */ 1169 if (options.jump_host != NULL) { 1170 char port_s[8]; 1171 const char *sshbin = argv0; 1172 1173 /* 1174 * Try to use SSH indicated by argv[0], but fall back to 1175 * "ssh" if it appears unavailable. 1176 */ 1177 if (strchr(argv0, '/') != NULL && access(argv0, X_OK) != 0) 1178 sshbin = "ssh"; 1179 1180 /* Consistency check */ 1181 if (options.proxy_command != NULL) 1182 fatal("inconsistent options: ProxyCommand+ProxyJump"); 1183 /* Never use FD passing for ProxyJump */ 1184 options.proxy_use_fdpass = 0; 1185 snprintf(port_s, sizeof(port_s), "%d", options.jump_port); 1186 xasprintf(&options.proxy_command, 1187 "%s%s%s%s%s%s%s%s%s%s%.*s -W '[%%h]:%%p' %s", 1188 sshbin, 1189 /* Optional "-l user" argument if jump_user set */ 1190 options.jump_user == NULL ? "" : " -l ", 1191 options.jump_user == NULL ? "" : options.jump_user, 1192 /* Optional "-p port" argument if jump_port set */ 1193 options.jump_port <= 0 ? "" : " -p ", 1194 options.jump_port <= 0 ? "" : port_s, 1195 /* Optional additional jump hosts ",..." */ 1196 options.jump_extra == NULL ? "" : " -J ", 1197 options.jump_extra == NULL ? "" : options.jump_extra, 1198 /* Optional "-F" argumment if -F specified */ 1199 config == NULL ? "" : " -F ", 1200 config == NULL ? "" : config, 1201 /* Optional "-v" arguments if -v set */ 1202 debug_flag ? " -" : "", 1203 debug_flag, "vvv", 1204 /* Mandatory hostname */ 1205 options.jump_host); 1206 debug("Setting implicit ProxyCommand from ProxyJump: %s", 1207 options.proxy_command); 1208 } 1209 1210 if (options.port == 0) 1211 options.port = default_ssh_port(); 1212 channel_set_af(ssh, options.address_family); 1213 1214 /* Tidy and check options */ 1215 if (options.host_key_alias != NULL) 1216 lowercase(options.host_key_alias); 1217 if (options.proxy_command != NULL && 1218 strcmp(options.proxy_command, "-") == 0 && 1219 options.proxy_use_fdpass) 1220 fatal("ProxyCommand=- and ProxyUseFDPass are incompatible"); 1221 if (options.control_persist && 1222 options.update_hostkeys == SSH_UPDATE_HOSTKEYS_ASK) { 1223 debug("UpdateHostKeys=ask is incompatible with ControlPersist; " 1224 "disabling"); 1225 options.update_hostkeys = 0; 1226 } 1227 if (options.connection_attempts <= 0) 1228 fatal("Invalid number of ConnectionAttempts"); 1229 1230 if (sshbuf_len(command) != 0 && options.remote_command != NULL) 1231 fatal("Cannot execute command-line and remote command."); 1232 1233 /* Cannot fork to background if no command. */ 1234 if (fork_after_authentication_flag && sshbuf_len(command) == 0 && 1235 options.remote_command == NULL && !no_shell_flag) 1236 fatal("Cannot fork into background without a command " 1237 "to execute."); 1238 1239 /* reinit */ 1240 log_init(argv0, options.log_level, options.log_facility, !use_syslog); 1241 1242 if (options.request_tty == REQUEST_TTY_YES || 1243 options.request_tty == REQUEST_TTY_FORCE) 1244 tty_flag = 1; 1245 1246 /* Allocate a tty by default if no command specified. */ 1247 if (sshbuf_len(command) == 0 && options.remote_command == NULL) 1248 tty_flag = options.request_tty != REQUEST_TTY_NO; 1249 1250 /* Force no tty */ 1251 if (options.request_tty == REQUEST_TTY_NO || 1252 (muxclient_command && muxclient_command != SSHMUX_COMMAND_PROXY)) 1253 tty_flag = 0; 1254 /* Do not allocate a tty if stdin is not a tty. */ 1255 if ((!isatty(fileno(stdin)) || stdin_null_flag) && 1256 options.request_tty != REQUEST_TTY_FORCE) { 1257 if (tty_flag) 1258 logit("Pseudo-terminal will not be allocated because " 1259 "stdin is not a terminal."); 1260 tty_flag = 0; 1261 } 1262 1263 seed_rng(); 1264 1265 if (options.user == NULL) 1266 options.user = xstrdup(pw->pw_name); 1267 1268 /* Set up strings used to percent_expand() arguments */ 1269 if (gethostname(thishost, sizeof(thishost)) == -1) 1270 fatal("gethostname: %s", strerror(errno)); 1271 strlcpy(shorthost, thishost, sizeof(shorthost)); 1272 shorthost[strcspn(thishost, ".")] = '\0'; 1273 snprintf(portstr, sizeof(portstr), "%d", options.port); 1274 snprintf(uidstr, sizeof(uidstr), "%llu", 1275 (unsigned long long)pw->pw_uid); 1276 1277 /* Find canonic host name. */ 1278 if (strchr(host, '.') == 0) { 1279 struct addrinfo hints; 1280 struct addrinfo *ai = NULL; 1281 int errgai; 1282 memset(&hints, 0, sizeof(hints)); 1283 hints.ai_family = options.address_family; 1284 hints.ai_flags = AI_CANONNAME; 1285 hints.ai_socktype = SOCK_STREAM; 1286 errgai = getaddrinfo(host, NULL, &hints, &ai); 1287 if (errgai == 0) { 1288 if (ai->ai_canonname != NULL) 1289 host = xstrdup(ai->ai_canonname); 1290 freeaddrinfo(ai); 1291 } 1292 } 1293 1294 if ((md = ssh_digest_start(SSH_DIGEST_SHA1)) == NULL || 1295 ssh_digest_update(md, thishost, strlen(thishost)) < 0 || 1296 ssh_digest_update(md, host, strlen(host)) < 0 || 1297 ssh_digest_update(md, portstr, strlen(portstr)) < 0 || 1298 ssh_digest_update(md, options.user, strlen(options.user)) < 0 || 1299 ssh_digest_final(md, conn_hash, sizeof(conn_hash)) < 0) 1300 fatal("%s: mux digest failed", __func__); 1301 ssh_digest_free(md); 1302 conn_hash_hex = tohex(conn_hash, ssh_digest_bytes(SSH_DIGEST_SHA1)); 1303 1304 /* 1305 * Expand tokens in arguments. NB. LocalCommand is expanded later, 1306 * after port-forwarding is set up, so it may pick up any local 1307 * tunnel interface name allocated. 1308 */ 1309 if (options.remote_command != NULL) { 1310 debug3("expanding RemoteCommand: %s", options.remote_command); 1311 cp = options.remote_command; 1312 options.remote_command = percent_expand(cp, 1313 "C", conn_hash_hex, 1314 "L", shorthost, 1315 "d", pw->pw_dir, 1316 "h", host, 1317 "i", uidstr, 1318 "l", thishost, 1319 "n", host_arg, 1320 "p", portstr, 1321 "r", options.user, 1322 "u", pw->pw_name, 1323 (char *)NULL); 1324 debug3("expanded RemoteCommand: %s", options.remote_command); 1325 free(cp); 1326 if ((r = sshbuf_put(command, options.remote_command, 1327 strlen(options.remote_command))) != 0) 1328 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 1329 } 1330 1331 if (options.control_path != NULL) { 1332 cp = tilde_expand_filename(options.control_path, getuid()); 1333 free(options.control_path); 1334 options.control_path = percent_expand(cp, 1335 "C", conn_hash_hex, 1336 "L", shorthost, 1337 "h", host, 1338 "i", uidstr, 1339 "l", thishost, 1340 "n", host_arg, 1341 "p", portstr, 1342 "r", options.user, 1343 "u", pw->pw_name, 1344 "i", uidstr, 1345 (char *)NULL); 1346 free(cp); 1347 } 1348 1349 if (config_test) { 1350 dump_client_config(&options, host); 1351 exit(0); 1352 } 1353 1354 if (muxclient_command != 0 && options.control_path == NULL) 1355 fatal("No ControlPath specified for \"-O\" command"); 1356 if (options.control_path != NULL) { 1357 int sock; 1358 if ((sock = muxclient(options.control_path)) >= 0) { 1359 ssh_packet_set_connection(ssh, sock, sock); 1360 packet_set_mux(); 1361 goto skip_connect; 1362 } 1363 } 1364 1365 /* 1366 * If hostname canonicalisation was not enabled, then we may not 1367 * have yet resolved the hostname. Do so now. 1368 */ 1369 if (addrs == NULL && options.proxy_command == NULL) { 1370 debug2("resolving \"%s\" port %d", host, options.port); 1371 if ((addrs = resolve_host(host, options.port, 1, 1372 cname, sizeof(cname))) == NULL) 1373 cleanup_exit(255); /* resolve_host logs the error */ 1374 } 1375 1376 timeout_ms = options.connection_timeout * 1000; 1377 1378 /* Open a connection to the remote host. */ 1379 if (ssh_connect(ssh, host, addrs, &hostaddr, options.port, 1380 options.address_family, options.connection_attempts, 1381 &timeout_ms, options.tcp_keep_alive) != 0) 1382 exit(255); 1383 1384 if (addrs != NULL) 1385 freeaddrinfo(addrs); 1386 1387 packet_set_timeout(options.server_alive_interval, 1388 options.server_alive_count_max); 1389 1390 ssh = active_state; /* XXX */ 1391 1392 if (timeout_ms > 0) 1393 debug3("timeout: %d ms remain after connect", timeout_ms); 1394 1395 /* 1396 * If we successfully made the connection and we have hostbased auth 1397 * enabled, load the public keys so we can later use the ssh-keysign 1398 * helper to sign challenges. 1399 */ 1400 sensitive_data.nkeys = 0; 1401 sensitive_data.keys = NULL; 1402 if (options.hostbased_authentication) { 1403 sensitive_data.nkeys = 10; 1404 sensitive_data.keys = xcalloc(sensitive_data.nkeys, 1405 sizeof(struct sshkey)); 1406 1407 /* XXX check errors? */ 1408#define L_PUBKEY(p,o) do { \ 1409 if ((o) >= sensitive_data.nkeys) \ 1410 fatal("%s pubkey out of array bounds", __func__); \ 1411 check_load(sshkey_load_public(p, &(sensitive_data.keys[o]), NULL), \ 1412 p, "pubkey"); \ 1413} while (0) 1414#define L_CERT(p,o) do { \ 1415 if ((o) >= sensitive_data.nkeys) \ 1416 fatal("%s cert out of array bounds", __func__); \ 1417 check_load(sshkey_load_cert(p, &(sensitive_data.keys[o])), p, "cert"); \ 1418} while (0) 1419 1420 if (options.hostbased_authentication == 1) { 1421 L_CERT(_PATH_HOST_ECDSA_KEY_FILE, 0); 1422 L_CERT(_PATH_HOST_ED25519_KEY_FILE, 1); 1423 L_CERT(_PATH_HOST_RSA_KEY_FILE, 2); 1424 L_CERT(_PATH_HOST_DSA_KEY_FILE, 3); 1425 L_PUBKEY(_PATH_HOST_ECDSA_KEY_FILE, 4); 1426 L_PUBKEY(_PATH_HOST_ED25519_KEY_FILE, 5); 1427 L_PUBKEY(_PATH_HOST_RSA_KEY_FILE, 6); 1428 L_PUBKEY(_PATH_HOST_DSA_KEY_FILE, 7); 1429 L_CERT(_PATH_HOST_XMSS_KEY_FILE, 8); 1430 L_PUBKEY(_PATH_HOST_XMSS_KEY_FILE, 9); 1431 } 1432 } 1433 1434 /* Create ~/.ssh * directory if it doesn't already exist. */ 1435 if (config == NULL) { 1436 r = snprintf(buf, sizeof buf, "%s%s%s", pw->pw_dir, 1437 strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR); 1438 if (r > 0 && (size_t)r < sizeof(buf) && stat(buf, &st) < 0) { 1439#ifdef WITH_SELINUX 1440 ssh_selinux_setfscreatecon(buf); 1441#endif 1442 if (mkdir(buf, 0700) < 0) 1443 error("Could not create directory '%.200s'.", 1444 buf); 1445#ifdef WITH_SELINUX 1446 ssh_selinux_setfscreatecon(NULL); 1447#endif 1448 } 1449 } 1450 /* load options.identity_files */ 1451 load_public_identity_files(pw); 1452 1453 /* optionally set the SSH_AUTHSOCKET_ENV_NAME variable */ 1454 if (options.identity_agent && 1455 strcmp(options.identity_agent, SSH_AUTHSOCKET_ENV_NAME) != 0) { 1456 if (strcmp(options.identity_agent, "none") == 0) { 1457 unsetenv(SSH_AUTHSOCKET_ENV_NAME); 1458 } else { 1459 p = tilde_expand_filename(options.identity_agent, 1460 getuid()); 1461 cp = percent_expand(p, 1462 "d", pw->pw_dir, 1463 "h", host, 1464 "i", uidstr, 1465 "l", thishost, 1466 "r", options.user, 1467 "u", pw->pw_name, 1468 (char *)NULL); 1469 free(p); 1470 /* 1471 * If identity_agent represents an environment variable 1472 * then recheck that it is valid (since processing with 1473 * percent_expand() may have changed it) and substitute 1474 * its value. 1475 */ 1476 if (cp[0] == '$') { 1477 if (!valid_env_name(cp + 1)) { 1478 fatal("Invalid IdentityAgent " 1479 "environment variable name %s", cp); 1480 } 1481 if ((p = getenv(cp + 1)) == NULL) 1482 unsetenv(SSH_AUTHSOCKET_ENV_NAME); 1483 else 1484 setenv(SSH_AUTHSOCKET_ENV_NAME, p, 1); 1485 } else { 1486 /* identity_agent specifies a path directly */ 1487 setenv(SSH_AUTHSOCKET_ENV_NAME, cp, 1); 1488 } 1489 free(cp); 1490 } 1491 } 1492 1493 /* Expand ~ in known host file names. */ 1494 tilde_expand_paths(options.system_hostfiles, 1495 options.num_system_hostfiles); 1496 tilde_expand_paths(options.user_hostfiles, options.num_user_hostfiles); 1497 1498 signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */ 1499 signal(SIGCHLD, main_sigchld_handler); 1500 1501 /* Log into the remote system. Never returns if the login fails. */ 1502 ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr, 1503 options.port, pw, timeout_ms); 1504 1505 if (packet_connection_is_on_socket()) { 1506 verbose("Authenticated to %s ([%s]:%d).", host, 1507 ssh_remote_ipaddr(ssh), ssh_remote_port(ssh)); 1508 } else { 1509 verbose("Authenticated to %s (via proxy).", host); 1510 } 1511 1512 /* We no longer need the private host keys. Clear them now. */ 1513 if (sensitive_data.nkeys != 0) { 1514 for (i = 0; i < sensitive_data.nkeys; i++) { 1515 if (sensitive_data.keys[i] != NULL) { 1516 /* Destroys contents safely */ 1517 debug3("clear hostkey %d", i); 1518 sshkey_free(sensitive_data.keys[i]); 1519 sensitive_data.keys[i] = NULL; 1520 } 1521 } 1522 free(sensitive_data.keys); 1523 } 1524 for (i = 0; i < options.num_identity_files; i++) { 1525 free(options.identity_files[i]); 1526 options.identity_files[i] = NULL; 1527 if (options.identity_keys[i]) { 1528 sshkey_free(options.identity_keys[i]); 1529 options.identity_keys[i] = NULL; 1530 } 1531 } 1532 for (i = 0; i < options.num_certificate_files; i++) { 1533 free(options.certificate_files[i]); 1534 options.certificate_files[i] = NULL; 1535 } 1536 1537 skip_connect: 1538 exit_status = ssh_session2(ssh, pw); 1539 packet_close(); 1540 1541 if (options.control_path != NULL && muxserver_sock != -1) 1542 unlink(options.control_path); 1543 1544 /* Kill ProxyCommand if it is running. */ 1545 ssh_kill_proxy_command(); 1546 1547 return exit_status; 1548} 1549 1550static void 1551control_persist_detach(void) 1552{ 1553 pid_t pid; 1554 int devnull, keep_stderr; 1555 1556 debug("%s: backgrounding master process", __func__); 1557 1558 /* 1559 * master (current process) into the background, and make the 1560 * foreground process a client of the backgrounded master. 1561 */ 1562 switch ((pid = fork())) { 1563 case -1: 1564 fatal("%s: fork: %s", __func__, strerror(errno)); 1565 case 0: 1566 /* Child: master process continues mainloop */ 1567 break; 1568 default: 1569 /* Parent: set up mux slave to connect to backgrounded master */ 1570 debug2("%s: background process is %ld", __func__, (long)pid); 1571 stdin_null_flag = ostdin_null_flag; 1572 options.request_tty = orequest_tty; 1573 tty_flag = otty_flag; 1574 close(muxserver_sock); 1575 muxserver_sock = -1; 1576 options.control_master = SSHCTL_MASTER_NO; 1577 muxclient(options.control_path); 1578 /* muxclient() doesn't return on success. */ 1579 fatal("Failed to connect to new control master"); 1580 } 1581 if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) { 1582 error("%s: open(\"/dev/null\"): %s", __func__, 1583 strerror(errno)); 1584 } else { 1585 keep_stderr = log_is_on_stderr() && debug_flag; 1586 if (dup2(devnull, STDIN_FILENO) == -1 || 1587 dup2(devnull, STDOUT_FILENO) == -1 || 1588 (!keep_stderr && dup2(devnull, STDERR_FILENO) == -1)) 1589 error("%s: dup2: %s", __func__, strerror(errno)); 1590 if (devnull > STDERR_FILENO) 1591 close(devnull); 1592 } 1593 daemon(1, 1); 1594 setproctitle("%s [mux]", options.control_path); 1595} 1596 1597/* Do fork() after authentication. Used by "ssh -f" */ 1598static void 1599fork_postauth(void) 1600{ 1601 if (need_controlpersist_detach) 1602 control_persist_detach(); 1603 debug("forking to background"); 1604 fork_after_authentication_flag = 0; 1605 if (daemon(1, 1) < 0) 1606 fatal("daemon() failed: %.200s", strerror(errno)); 1607} 1608 1609/* Callback for remote forward global requests */ 1610static void 1611ssh_confirm_remote_forward(struct ssh *ssh, int type, u_int32_t seq, void *ctxt) 1612{ 1613 struct Forward *rfwd = (struct Forward *)ctxt; 1614 1615 /* XXX verbose() on failure? */ 1616 debug("remote forward %s for: listen %s%s%d, connect %s:%d", 1617 type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure", 1618 rfwd->listen_path ? rfwd->listen_path : 1619 rfwd->listen_host ? rfwd->listen_host : "", 1620 (rfwd->listen_path || rfwd->listen_host) ? ":" : "", 1621 rfwd->listen_port, rfwd->connect_path ? rfwd->connect_path : 1622 rfwd->connect_host, rfwd->connect_port); 1623 if (rfwd->listen_path == NULL && rfwd->listen_port == 0) { 1624 if (type == SSH2_MSG_REQUEST_SUCCESS) { 1625 rfwd->allocated_port = packet_get_int(); 1626 logit("Allocated port %u for remote forward to %s:%d", 1627 rfwd->allocated_port, 1628 rfwd->connect_host, rfwd->connect_port); 1629 channel_update_permission(ssh, 1630 rfwd->handle, rfwd->allocated_port); 1631 } else { 1632 channel_update_permission(ssh, rfwd->handle, -1); 1633 } 1634 } 1635 1636 if (type == SSH2_MSG_REQUEST_FAILURE) { 1637 if (options.exit_on_forward_failure) { 1638 if (rfwd->listen_path != NULL) 1639 fatal("Error: remote port forwarding failed " 1640 "for listen path %s", rfwd->listen_path); 1641 else 1642 fatal("Error: remote port forwarding failed " 1643 "for listen port %d", rfwd->listen_port); 1644 } else { 1645 if (rfwd->listen_path != NULL) 1646 logit("Warning: remote port forwarding failed " 1647 "for listen path %s", rfwd->listen_path); 1648 else 1649 logit("Warning: remote port forwarding failed " 1650 "for listen port %d", rfwd->listen_port); 1651 } 1652 } 1653 if (++remote_forward_confirms_received == options.num_remote_forwards) { 1654 debug("All remote forwarding requests processed"); 1655 if (fork_after_authentication_flag) 1656 fork_postauth(); 1657 } 1658} 1659 1660static void 1661client_cleanup_stdio_fwd(struct ssh *ssh, int id, void *arg) 1662{ 1663 debug("stdio forwarding: done"); 1664 cleanup_exit(0); 1665} 1666 1667static void 1668ssh_stdio_confirm(struct ssh *ssh, int id, int success, void *arg) 1669{ 1670 if (!success) 1671 fatal("stdio forwarding failed"); 1672} 1673 1674static void 1675ssh_init_stdio_forwarding(struct ssh *ssh) 1676{ 1677 Channel *c; 1678 int in, out; 1679 1680 if (options.stdio_forward_host == NULL) 1681 return; 1682 1683 debug3("%s: %s:%d", __func__, options.stdio_forward_host, 1684 options.stdio_forward_port); 1685 1686 if ((in = dup(STDIN_FILENO)) < 0 || 1687 (out = dup(STDOUT_FILENO)) < 0) 1688 fatal("channel_connect_stdio_fwd: dup() in/out failed"); 1689 if ((c = channel_connect_stdio_fwd(ssh, options.stdio_forward_host, 1690 options.stdio_forward_port, in, out)) == NULL) 1691 fatal("%s: channel_connect_stdio_fwd failed", __func__); 1692 channel_register_cleanup(ssh, c->self, client_cleanup_stdio_fwd, 0); 1693 channel_register_open_confirm(ssh, c->self, ssh_stdio_confirm, NULL); 1694} 1695 1696static void 1697ssh_init_forwarding(struct ssh *ssh, char **ifname) 1698{ 1699 int success = 0; 1700 int i; 1701 1702 /* Initiate local TCP/IP port forwardings. */ 1703 for (i = 0; i < options.num_local_forwards; i++) { 1704 debug("Local connections to %.200s:%d forwarded to remote " 1705 "address %.200s:%d", 1706 (options.local_forwards[i].listen_path != NULL) ? 1707 options.local_forwards[i].listen_path : 1708 (options.local_forwards[i].listen_host == NULL) ? 1709 (options.fwd_opts.gateway_ports ? "*" : "LOCALHOST") : 1710 options.local_forwards[i].listen_host, 1711 options.local_forwards[i].listen_port, 1712 (options.local_forwards[i].connect_path != NULL) ? 1713 options.local_forwards[i].connect_path : 1714 options.local_forwards[i].connect_host, 1715 options.local_forwards[i].connect_port); 1716 success += channel_setup_local_fwd_listener(ssh, 1717 &options.local_forwards[i], &options.fwd_opts); 1718 } 1719 if (i > 0 && success != i && options.exit_on_forward_failure) 1720 fatal("Could not request local forwarding."); 1721 if (i > 0 && success == 0) 1722 error("Could not request local forwarding."); 1723 1724 /* Initiate remote TCP/IP port forwardings. */ 1725 for (i = 0; i < options.num_remote_forwards; i++) { 1726 debug("Remote connections from %.200s:%d forwarded to " 1727 "local address %.200s:%d", 1728 (options.remote_forwards[i].listen_path != NULL) ? 1729 options.remote_forwards[i].listen_path : 1730 (options.remote_forwards[i].listen_host == NULL) ? 1731 "LOCALHOST" : options.remote_forwards[i].listen_host, 1732 options.remote_forwards[i].listen_port, 1733 (options.remote_forwards[i].connect_path != NULL) ? 1734 options.remote_forwards[i].connect_path : 1735 options.remote_forwards[i].connect_host, 1736 options.remote_forwards[i].connect_port); 1737 options.remote_forwards[i].handle = 1738 channel_request_remote_forwarding(ssh, 1739 &options.remote_forwards[i]); 1740 if (options.remote_forwards[i].handle < 0) { 1741 if (options.exit_on_forward_failure) 1742 fatal("Could not request remote forwarding."); 1743 else 1744 logit("Warning: Could not request remote " 1745 "forwarding."); 1746 } else { 1747 client_register_global_confirm( 1748 ssh_confirm_remote_forward, 1749 &options.remote_forwards[i]); 1750 } 1751 } 1752 1753 /* Initiate tunnel forwarding. */ 1754 if (options.tun_open != SSH_TUNMODE_NO) { 1755 if ((*ifname = client_request_tun_fwd(ssh, 1756 options.tun_open, options.tun_local, 1757 options.tun_remote)) == NULL) { 1758 if (options.exit_on_forward_failure) 1759 fatal("Could not request tunnel forwarding."); 1760 else 1761 error("Could not request tunnel forwarding."); 1762 } 1763 } 1764} 1765 1766static void 1767check_agent_present(void) 1768{ 1769 int r; 1770 1771 if (options.forward_agent) { 1772 /* Clear agent forwarding if we don't have an agent. */ 1773 if ((r = ssh_get_authentication_socket(NULL)) != 0) { 1774 options.forward_agent = 0; 1775 if (r != SSH_ERR_AGENT_NOT_PRESENT) 1776 debug("ssh_get_authentication_socket: %s", 1777 ssh_err(r)); 1778 } 1779 } 1780} 1781 1782static void 1783ssh_session2_setup(struct ssh *ssh, int id, int success, void *arg) 1784{ 1785 extern char **environ; 1786 const char *display; 1787 int interactive = tty_flag; 1788 char *proto = NULL, *data = NULL; 1789 1790 if (!success) 1791 return; /* No need for error message, channels code sens one */ 1792 1793 display = getenv("DISPLAY"); 1794 if (display == NULL && options.forward_x11) 1795 debug("X11 forwarding requested but DISPLAY not set"); 1796 if (options.forward_x11 && client_x11_get_proto(ssh, display, 1797 options.xauth_location, options.forward_x11_trusted, 1798 options.forward_x11_timeout, &proto, &data) == 0) { 1799 /* Request forwarding with authentication spoofing. */ 1800 debug("Requesting X11 forwarding with authentication " 1801 "spoofing."); 1802 x11_request_forwarding_with_spoofing(ssh, id, display, proto, 1803 data, 1); 1804 client_expect_confirm(ssh, id, "X11 forwarding", CONFIRM_WARN); 1805 /* XXX exit_on_forward_failure */ 1806 interactive = 1; 1807 } 1808 1809 check_agent_present(); 1810 if (options.forward_agent) { 1811 debug("Requesting authentication agent forwarding."); 1812 channel_request_start(ssh, id, "auth-agent-req@openssh.com", 0); 1813 packet_send(); 1814 } 1815 1816 /* Tell the packet module whether this is an interactive session. */ 1817 packet_set_interactive(interactive, 1818 options.ip_qos_interactive, options.ip_qos_bulk); 1819 1820 client_session2_setup(ssh, id, tty_flag, subsystem_flag, getenv("TERM"), 1821 NULL, fileno(stdin), command, environ); 1822} 1823 1824/* open new channel for a session */ 1825static int 1826ssh_session2_open(struct ssh *ssh) 1827{ 1828 Channel *c; 1829 int window, packetmax, in, out, err; 1830 1831 if (stdin_null_flag) { 1832 in = open(_PATH_DEVNULL, O_RDONLY); 1833 } else { 1834 in = dup(STDIN_FILENO); 1835 } 1836 out = dup(STDOUT_FILENO); 1837 err = dup(STDERR_FILENO); 1838 1839 if (in < 0 || out < 0 || err < 0) 1840 fatal("dup() in/out/err failed"); 1841 1842 /* enable nonblocking unless tty */ 1843 if (!isatty(in)) 1844 set_nonblock(in); 1845 if (!isatty(out)) 1846 set_nonblock(out); 1847 if (!isatty(err)) 1848 set_nonblock(err); 1849 1850 window = CHAN_SES_WINDOW_DEFAULT; 1851 packetmax = CHAN_SES_PACKET_DEFAULT; 1852 if (tty_flag) { 1853 window >>= 1; 1854 packetmax >>= 1; 1855 } 1856 c = channel_new(ssh, 1857 "session", SSH_CHANNEL_OPENING, in, out, err, 1858 window, packetmax, CHAN_EXTENDED_WRITE, 1859 "client-session", /*nonblock*/0); 1860 1861 debug3("%s: channel_new: %d", __func__, c->self); 1862 1863 channel_send_open(ssh, c->self); 1864 if (!no_shell_flag) 1865 channel_register_open_confirm(ssh, c->self, 1866 ssh_session2_setup, NULL); 1867 1868 return c->self; 1869} 1870 1871static int 1872ssh_session2(struct ssh *ssh, struct passwd *pw) 1873{ 1874 int devnull, id = -1; 1875 char *cp, *tun_fwd_ifname = NULL; 1876 1877 /* XXX should be pre-session */ 1878 if (!options.control_persist) 1879 ssh_init_stdio_forwarding(ssh); 1880 1881 ssh_init_forwarding(ssh, &tun_fwd_ifname); 1882 1883 if (options.local_command != NULL) { 1884 debug3("expanding LocalCommand: %s", options.local_command); 1885 cp = options.local_command; 1886 options.local_command = percent_expand(cp, 1887 "C", conn_hash_hex, 1888 "L", shorthost, 1889 "d", pw->pw_dir, 1890 "h", host, 1891 "i", uidstr, 1892 "l", thishost, 1893 "n", host_arg, 1894 "p", portstr, 1895 "r", options.user, 1896 "u", pw->pw_name, 1897 "T", tun_fwd_ifname == NULL ? "NONE" : tun_fwd_ifname, 1898 (char *)NULL); 1899 debug3("expanded LocalCommand: %s", options.local_command); 1900 free(cp); 1901 } 1902 1903 /* Start listening for multiplex clients */ 1904 if (!packet_get_mux()) 1905 muxserver_listen(ssh); 1906 1907 /* 1908 * If we are in control persist mode and have a working mux listen 1909 * socket, then prepare to background ourselves and have a foreground 1910 * client attach as a control slave. 1911 * NB. we must save copies of the flags that we override for 1912 * the backgrounding, since we defer attachment of the slave until 1913 * after the connection is fully established (in particular, 1914 * async rfwd replies have been received for ExitOnForwardFailure). 1915 */ 1916 if (options.control_persist && muxserver_sock != -1) { 1917 ostdin_null_flag = stdin_null_flag; 1918 ono_shell_flag = no_shell_flag; 1919 orequest_tty = options.request_tty; 1920 otty_flag = tty_flag; 1921 stdin_null_flag = 1; 1922 no_shell_flag = 1; 1923 tty_flag = 0; 1924 if (!fork_after_authentication_flag) 1925 need_controlpersist_detach = 1; 1926 fork_after_authentication_flag = 1; 1927 } 1928 /* 1929 * ControlPersist mux listen socket setup failed, attempt the 1930 * stdio forward setup that we skipped earlier. 1931 */ 1932 if (options.control_persist && muxserver_sock == -1) 1933 ssh_init_stdio_forwarding(ssh); 1934 1935 if (!no_shell_flag) 1936 id = ssh_session2_open(ssh); 1937 else { 1938 packet_set_interactive( 1939 options.control_master == SSHCTL_MASTER_NO, 1940 options.ip_qos_interactive, options.ip_qos_bulk); 1941 } 1942 1943 /* If we don't expect to open a new session, then disallow it */ 1944 if (options.control_master == SSHCTL_MASTER_NO && 1945 (datafellows & SSH_NEW_OPENSSH)) { 1946 debug("Requesting no-more-sessions@openssh.com"); 1947 packet_start(SSH2_MSG_GLOBAL_REQUEST); 1948 packet_put_cstring("no-more-sessions@openssh.com"); 1949 packet_put_char(0); 1950 packet_send(); 1951 } 1952 1953 /* Execute a local command */ 1954 if (options.local_command != NULL && 1955 options.permit_local_command) 1956 ssh_local_cmd(options.local_command); 1957 1958 /* 1959 * stdout is now owned by the session channel; clobber it here 1960 * so future channel closes are propagated to the local fd. 1961 * NB. this can only happen after LocalCommand has completed, 1962 * as it may want to write to stdout. 1963 */ 1964 if (!need_controlpersist_detach) { 1965 if ((devnull = open(_PATH_DEVNULL, O_WRONLY)) == -1) 1966 error("%s: open %s: %s", __func__, 1967 _PATH_DEVNULL, strerror(errno)); 1968 if (dup2(devnull, STDOUT_FILENO) < 0) 1969 fatal("%s: dup2() stdout failed", __func__); 1970 if (devnull > STDERR_FILENO) 1971 close(devnull); 1972 } 1973 1974 /* 1975 * If requested and we are not interested in replies to remote 1976 * forwarding requests, then let ssh continue in the background. 1977 */ 1978 if (fork_after_authentication_flag) { 1979 if (options.exit_on_forward_failure && 1980 options.num_remote_forwards > 0) { 1981 debug("deferring postauth fork until remote forward " 1982 "confirmation received"); 1983 } else 1984 fork_postauth(); 1985 } 1986 1987 return client_loop(ssh, tty_flag, tty_flag ? 1988 options.escape_char : SSH_ESCAPECHAR_NONE, id); 1989} 1990 1991/* Loads all IdentityFile and CertificateFile keys */ 1992static void 1993load_public_identity_files(struct passwd *pw) 1994{ 1995 char *filename, *cp; 1996 struct sshkey *public; 1997 int i; 1998 u_int n_ids, n_certs; 1999 char *identity_files[SSH_MAX_IDENTITY_FILES]; 2000 struct sshkey *identity_keys[SSH_MAX_IDENTITY_FILES]; 2001 int identity_file_userprovided[SSH_MAX_IDENTITY_FILES]; 2002 char *certificate_files[SSH_MAX_CERTIFICATE_FILES]; 2003 struct sshkey *certificates[SSH_MAX_CERTIFICATE_FILES]; 2004 int certificate_file_userprovided[SSH_MAX_CERTIFICATE_FILES]; 2005#ifdef ENABLE_PKCS11 2006 struct sshkey **keys; 2007 int nkeys; 2008#endif /* PKCS11 */ 2009 2010 n_ids = n_certs = 0; 2011 memset(identity_files, 0, sizeof(identity_files)); 2012 memset(identity_keys, 0, sizeof(identity_keys)); 2013 memset(identity_file_userprovided, 0, 2014 sizeof(identity_file_userprovided)); 2015 memset(certificate_files, 0, sizeof(certificate_files)); 2016 memset(certificates, 0, sizeof(certificates)); 2017 memset(certificate_file_userprovided, 0, 2018 sizeof(certificate_file_userprovided)); 2019 2020#ifdef ENABLE_PKCS11 2021 if (options.pkcs11_provider != NULL && 2022 options.num_identity_files < SSH_MAX_IDENTITY_FILES && 2023 (pkcs11_init(!options.batch_mode) == 0) && 2024 (nkeys = pkcs11_add_provider(options.pkcs11_provider, NULL, 2025 &keys)) > 0) { 2026 for (i = 0; i < nkeys; i++) { 2027 if (n_ids >= SSH_MAX_IDENTITY_FILES) { 2028 sshkey_free(keys[i]); 2029 continue; 2030 } 2031 identity_keys[n_ids] = keys[i]; 2032 identity_files[n_ids] = 2033 xstrdup(options.pkcs11_provider); /* XXX */ 2034 n_ids++; 2035 } 2036 free(keys); 2037 } 2038#endif /* ENABLE_PKCS11 */ 2039 for (i = 0; i < options.num_identity_files; i++) { 2040 if (n_ids >= SSH_MAX_IDENTITY_FILES || 2041 strcasecmp(options.identity_files[i], "none") == 0) { 2042 free(options.identity_files[i]); 2043 options.identity_files[i] = NULL; 2044 continue; 2045 } 2046 cp = tilde_expand_filename(options.identity_files[i], getuid()); 2047 filename = percent_expand(cp, "d", pw->pw_dir, 2048 "u", pw->pw_name, "l", thishost, "h", host, 2049 "r", options.user, (char *)NULL); 2050 free(cp); 2051 check_load(sshkey_load_public(filename, &public, NULL), 2052 filename, "pubkey"); 2053 debug("identity file %s type %d", filename, 2054 public ? public->type : -1); 2055 free(options.identity_files[i]); 2056 identity_files[n_ids] = filename; 2057 identity_keys[n_ids] = public; 2058 identity_file_userprovided[n_ids] = 2059 options.identity_file_userprovided[i]; 2060 if (++n_ids >= SSH_MAX_IDENTITY_FILES) 2061 continue; 2062 2063 /* 2064 * If no certificates have been explicitly listed then try 2065 * to add the default certificate variant too. 2066 */ 2067 if (options.num_certificate_files != 0) 2068 continue; 2069 xasprintf(&cp, "%s-cert", filename); 2070 check_load(sshkey_load_public(cp, &public, NULL), 2071 filename, "pubkey"); 2072 debug("identity file %s type %d", cp, 2073 public ? public->type : -1); 2074 if (public == NULL) { 2075 free(cp); 2076 continue; 2077 } 2078 if (!sshkey_is_cert(public)) { 2079 debug("%s: key %s type %s is not a certificate", 2080 __func__, cp, sshkey_type(public)); 2081 sshkey_free(public); 2082 free(cp); 2083 continue; 2084 } 2085 /* NB. leave filename pointing to private key */ 2086 identity_files[n_ids] = xstrdup(filename); 2087 identity_keys[n_ids] = public; 2088 identity_file_userprovided[n_ids] = 2089 options.identity_file_userprovided[i]; 2090 n_ids++; 2091 } 2092 2093 if (options.num_certificate_files > SSH_MAX_CERTIFICATE_FILES) 2094 fatal("%s: too many certificates", __func__); 2095 for (i = 0; i < options.num_certificate_files; i++) { 2096 cp = tilde_expand_filename(options.certificate_files[i], 2097 getuid()); 2098 filename = percent_expand(cp, 2099 "d", pw->pw_dir, 2100 "h", host, 2101 "i", uidstr, 2102 "l", thishost, 2103 "r", options.user, 2104 "u", pw->pw_name, 2105 (char *)NULL); 2106 free(cp); 2107 2108 check_load(sshkey_load_public(filename, &public, NULL), 2109 filename, "certificate"); 2110 debug("certificate file %s type %d", filename, 2111 public ? public->type : -1); 2112 free(options.certificate_files[i]); 2113 options.certificate_files[i] = NULL; 2114 if (public == NULL) { 2115 free(filename); 2116 continue; 2117 } 2118 if (!sshkey_is_cert(public)) { 2119 debug("%s: key %s type %s is not a certificate", 2120 __func__, filename, sshkey_type(public)); 2121 sshkey_free(public); 2122 free(filename); 2123 continue; 2124 } 2125 certificate_files[n_certs] = filename; 2126 certificates[n_certs] = public; 2127 certificate_file_userprovided[n_certs] = 2128 options.certificate_file_userprovided[i]; 2129 ++n_certs; 2130 } 2131 2132 options.num_identity_files = n_ids; 2133 memcpy(options.identity_files, identity_files, sizeof(identity_files)); 2134 memcpy(options.identity_keys, identity_keys, sizeof(identity_keys)); 2135 memcpy(options.identity_file_userprovided, 2136 identity_file_userprovided, sizeof(identity_file_userprovided)); 2137 2138 options.num_certificate_files = n_certs; 2139 memcpy(options.certificate_files, 2140 certificate_files, sizeof(certificate_files)); 2141 memcpy(options.certificates, certificates, sizeof(certificates)); 2142 memcpy(options.certificate_file_userprovided, 2143 certificate_file_userprovided, 2144 sizeof(certificate_file_userprovided)); 2145} 2146 2147static void 2148main_sigchld_handler(int sig) 2149{ 2150 int save_errno = errno; 2151 pid_t pid; 2152 int status; 2153 2154 while ((pid = waitpid(-1, &status, WNOHANG)) > 0 || 2155 (pid < 0 && errno == EINTR)) 2156 ; 2157 errno = save_errno; 2158} 2159