1 /* $OpenBSD: ssh.c,v 1.346 2010/08/12 21:49:44 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/param.h> 53 #include <sys/socket.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 71 #include <netinet/in.h> 72 #include <arpa/inet.h> 73 74 #include <openssl/evp.h> 75 #include <openssl/err.h> 76 #include "openbsd-compat/openssl-compat.h" 77 #include "openbsd-compat/sys-queue.h" 78 79 #include "xmalloc.h" 80 #include "ssh.h" 81 #include "ssh1.h" 82 #include "ssh2.h" 83 #include "canohost.h" 84 #include "compat.h" 85 #include "cipher.h" 86 #include "packet.h" 87 #include "buffer.h" 88 #include "channels.h" 89 #include "key.h" 90 #include "authfd.h" 91 #include "authfile.h" 92 #include "pathnames.h" 93 #include "dispatch.h" 94 #include "clientloop.h" 95 #include "log.h" 96 #include "readconf.h" 97 #include "sshconnect.h" 98 #include "misc.h" 99 #include "kex.h" 100 #include "mac.h" 101 #include "sshpty.h" 102 #include "match.h" 103 #include "msg.h" 104 #include "uidswap.h" 105 #include "roaming.h" 106 #include "version.h" 107 108 #ifdef ENABLE_PKCS11 109 #include "ssh-pkcs11.h" 110 #endif 111 112 extern char *__progname; 113 114 /* Flag indicating whether debug mode is on. May be set on the command line. */ 115 int debug_flag = 0; 116 117 /* Flag indicating whether a tty should be allocated */ 118 int tty_flag = 0; 119 int no_tty_flag = 0; 120 int force_tty_flag = 0; 121 122 /* don't exec a shell */ 123 int no_shell_flag = 0; 124 125 /* 126 * Flag indicating that nothing should be read from stdin. This can be set 127 * on the command line. 128 */ 129 int stdin_null_flag = 0; 130 131 /* 132 * Flag indicating that the current process should be backgrounded and 133 * a new slave launched in the foreground for ControlPersist. 134 */ 135 int need_controlpersist_detach = 0; 136 137 /* Copies of flags for ControlPersist foreground slave */ 138 int ostdin_null_flag, ono_shell_flag, ono_tty_flag, otty_flag; 139 140 /* 141 * Flag indicating that ssh should fork after authentication. This is useful 142 * so that the passphrase can be entered manually, and then ssh goes to the 143 * background. 144 */ 145 int fork_after_authentication_flag = 0; 146 147 /* forward stdio to remote host and port */ 148 char *stdio_forward_host = NULL; 149 int stdio_forward_port = 0; 150 151 /* 152 * General data structure for command line options and options configurable 153 * in configuration files. See readconf.h. 154 */ 155 Options options; 156 157 /* optional user configfile */ 158 char *config = NULL; 159 160 /* 161 * Name of the host we are connecting to. This is the name given on the 162 * command line, or the HostName specified for the user-supplied name in a 163 * configuration file. 164 */ 165 char *host; 166 167 /* socket address the host resolves to */ 168 struct sockaddr_storage hostaddr; 169 170 /* Private host keys. */ 171 Sensitive sensitive_data; 172 173 /* Original real UID. */ 174 uid_t original_real_uid; 175 uid_t original_effective_uid; 176 177 /* command to be executed */ 178 Buffer command; 179 180 /* Should we execute a command or invoke a subsystem? */ 181 int subsystem_flag = 0; 182 183 /* # of replies received for global requests */ 184 static int remote_forward_confirms_received = 0; 185 186 /* pid of proxycommand child process */ 187 pid_t proxy_command_pid = 0; 188 189 /* mux.c */ 190 extern int muxserver_sock; 191 extern u_int muxclient_command; 192 193 /* Prints a help message to the user. This function never returns. */ 194 195 static void 196 usage(void) 197 { 198 fprintf(stderr, 199 "usage: ssh [-1246AaCfgKkMNnqsTtVvXxYy] [-b bind_address] [-c cipher_spec]\n" 200 " [-D [bind_address:]port] [-e escape_char] [-F configfile]\n" 201 " [-I pkcs11] [-i identity_file]\n" 202 " [-L [bind_address:]port:host:hostport]\n" 203 " [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n" 204 " [-R [bind_address:]port:host:hostport] [-S ctl_path]\n" 205 " [-W host:port] [-w local_tun[:remote_tun]]\n" 206 " [user@]hostname [command]\n" 207 ); 208 exit(255); 209 } 210 211 static int ssh_session(void); 212 static int ssh_session2(void); 213 static void load_public_identity_files(void); 214 215 /* from muxclient.c */ 216 void muxclient(const char *); 217 void muxserver_listen(void); 218 219 /* 220 * Main program for the ssh client. 221 */ 222 int 223 main(int ac, char **av) 224 { 225 int i, r, opt, exit_status, use_syslog; 226 char *p, *cp, *line, *argv0, buf[MAXPATHLEN]; 227 struct stat st; 228 struct passwd *pw; 229 int dummy, timeout_ms; 230 extern int optind, optreset; 231 extern char *optarg; 232 struct servent *sp; 233 Forward fwd; 234 235 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ 236 sanitise_stdfd(); 237 238 __progname = ssh_get_progname(av[0]); 239 init_rng(); 240 241 /* 242 * Discard other fds that are hanging around. These can cause problem 243 * with backgrounded ssh processes started by ControlPersist. 244 */ 245 closefrom(STDERR_FILENO + 1); 246 247 /* 248 * Save the original real uid. It will be needed later (uid-swapping 249 * may clobber the real uid). 250 */ 251 original_real_uid = getuid(); 252 original_effective_uid = geteuid(); 253 254 /* 255 * Use uid-swapping to give up root privileges for the duration of 256 * option processing. We will re-instantiate the rights when we are 257 * ready to create the privileged port, and will permanently drop 258 * them when the port has been created (actually, when the connection 259 * has been made, as we may need to create the port several times). 260 */ 261 PRIV_END; 262 263 #ifdef HAVE_SETRLIMIT 264 /* If we are installed setuid root be careful to not drop core. */ 265 if (original_real_uid != original_effective_uid) { 266 struct rlimit rlim; 267 rlim.rlim_cur = rlim.rlim_max = 0; 268 if (setrlimit(RLIMIT_CORE, &rlim) < 0) 269 fatal("setrlimit failed: %.100s", strerror(errno)); 270 } 271 #endif 272 /* Get user data. */ 273 pw = getpwuid(original_real_uid); 274 if (!pw) { 275 logit("You don't exist, go away!"); 276 exit(255); 277 } 278 /* Take a copy of the returned structure. */ 279 pw = pwcopy(pw); 280 281 /* 282 * Set our umask to something reasonable, as some files are created 283 * with the default umask. This will make them world-readable but 284 * writable only by the owner, which is ok for all files for which we 285 * don't set the modes explicitly. 286 */ 287 umask(022); 288 289 /* 290 * Initialize option structure to indicate that no values have been 291 * set. 292 */ 293 initialize_options(&options); 294 295 /* Parse command-line arguments. */ 296 host = NULL; 297 use_syslog = 0; 298 argv0 = av[0]; 299 300 again: 301 while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx" 302 "ACD:F:I:KL:MNO:PR:S:TVw:W:XYy")) != -1) { 303 switch (opt) { 304 case '1': 305 options.protocol = SSH_PROTO_1; 306 break; 307 case '2': 308 options.protocol = SSH_PROTO_2; 309 break; 310 case '4': 311 options.address_family = AF_INET; 312 break; 313 case '6': 314 options.address_family = AF_INET6; 315 break; 316 case 'n': 317 stdin_null_flag = 1; 318 break; 319 case 'f': 320 fork_after_authentication_flag = 1; 321 stdin_null_flag = 1; 322 break; 323 case 'x': 324 options.forward_x11 = 0; 325 break; 326 case 'X': 327 options.forward_x11 = 1; 328 break; 329 case 'y': 330 use_syslog = 1; 331 break; 332 case 'Y': 333 options.forward_x11 = 1; 334 options.forward_x11_trusted = 1; 335 break; 336 case 'g': 337 options.gateway_ports = 1; 338 break; 339 case 'O': 340 if (stdio_forward_host != NULL) 341 fatal("Cannot specify multiplexing " 342 "command with -W"); 343 else if (muxclient_command != 0) 344 fatal("Multiplexing command already specified"); 345 if (strcmp(optarg, "check") == 0) 346 muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK; 347 else if (strcmp(optarg, "forward") == 0) 348 muxclient_command = SSHMUX_COMMAND_FORWARD; 349 else if (strcmp(optarg, "exit") == 0) 350 muxclient_command = SSHMUX_COMMAND_TERMINATE; 351 else 352 fatal("Invalid multiplex command."); 353 break; 354 case 'P': /* deprecated */ 355 options.use_privileged_port = 0; 356 break; 357 case 'a': 358 options.forward_agent = 0; 359 break; 360 case 'A': 361 options.forward_agent = 1; 362 break; 363 case 'k': 364 options.gss_deleg_creds = 0; 365 break; 366 case 'K': 367 options.gss_authentication = 1; 368 options.gss_deleg_creds = 1; 369 break; 370 case 'i': 371 if (stat(optarg, &st) < 0) { 372 fprintf(stderr, "Warning: Identity file %s " 373 "not accessible: %s.\n", optarg, 374 strerror(errno)); 375 break; 376 } 377 if (options.num_identity_files >= 378 SSH_MAX_IDENTITY_FILES) 379 fatal("Too many identity files specified " 380 "(max %d)", SSH_MAX_IDENTITY_FILES); 381 options.identity_files[options.num_identity_files++] = 382 xstrdup(optarg); 383 break; 384 case 'I': 385 #ifdef ENABLE_PKCS11 386 options.pkcs11_provider = xstrdup(optarg); 387 #else 388 fprintf(stderr, "no support for PKCS#11.\n"); 389 #endif 390 break; 391 case 't': 392 if (tty_flag) 393 force_tty_flag = 1; 394 tty_flag = 1; 395 break; 396 case 'v': 397 if (debug_flag == 0) { 398 debug_flag = 1; 399 options.log_level = SYSLOG_LEVEL_DEBUG1; 400 } else { 401 if (options.log_level < SYSLOG_LEVEL_DEBUG3) 402 options.log_level++; 403 break; 404 } 405 /* FALLTHROUGH */ 406 case 'V': 407 fprintf(stderr, "%s, %s\n", 408 SSH_RELEASE, SSLeay_version(SSLEAY_VERSION)); 409 if (opt == 'V') 410 exit(0); 411 break; 412 case 'w': 413 if (options.tun_open == -1) 414 options.tun_open = SSH_TUNMODE_DEFAULT; 415 options.tun_local = a2tun(optarg, &options.tun_remote); 416 if (options.tun_local == SSH_TUNID_ERR) { 417 fprintf(stderr, 418 "Bad tun device '%s'\n", optarg); 419 exit(255); 420 } 421 break; 422 case 'W': 423 if (stdio_forward_host != NULL) 424 fatal("stdio forward already specified"); 425 if (muxclient_command != 0) 426 fatal("Cannot specify stdio forward with -O"); 427 if (parse_forward(&fwd, optarg, 1, 0)) { 428 stdio_forward_host = fwd.listen_host; 429 stdio_forward_port = fwd.listen_port; 430 xfree(fwd.connect_host); 431 } else { 432 fprintf(stderr, 433 "Bad stdio forwarding specification '%s'\n", 434 optarg); 435 exit(255); 436 } 437 no_tty_flag = 1; 438 no_shell_flag = 1; 439 options.clear_forwardings = 1; 440 options.exit_on_forward_failure = 1; 441 break; 442 case 'q': 443 options.log_level = SYSLOG_LEVEL_QUIET; 444 break; 445 case 'e': 446 if (optarg[0] == '^' && optarg[2] == 0 && 447 (u_char) optarg[1] >= 64 && 448 (u_char) optarg[1] < 128) 449 options.escape_char = (u_char) optarg[1] & 31; 450 else if (strlen(optarg) == 1) 451 options.escape_char = (u_char) optarg[0]; 452 else if (strcmp(optarg, "none") == 0) 453 options.escape_char = SSH_ESCAPECHAR_NONE; 454 else { 455 fprintf(stderr, "Bad escape character '%s'.\n", 456 optarg); 457 exit(255); 458 } 459 break; 460 case 'c': 461 if (ciphers_valid(optarg)) { 462 /* SSH2 only */ 463 options.ciphers = xstrdup(optarg); 464 options.cipher = SSH_CIPHER_INVALID; 465 } else { 466 /* SSH1 only */ 467 options.cipher = cipher_number(optarg); 468 if (options.cipher == -1) { 469 fprintf(stderr, 470 "Unknown cipher type '%s'\n", 471 optarg); 472 exit(255); 473 } 474 if (options.cipher == SSH_CIPHER_3DES) 475 options.ciphers = "3des-cbc"; 476 else if (options.cipher == SSH_CIPHER_BLOWFISH) 477 options.ciphers = "blowfish-cbc"; 478 else 479 options.ciphers = (char *)-1; 480 } 481 break; 482 case 'm': 483 if (mac_valid(optarg)) 484 options.macs = xstrdup(optarg); 485 else { 486 fprintf(stderr, "Unknown mac type '%s'\n", 487 optarg); 488 exit(255); 489 } 490 break; 491 case 'M': 492 if (options.control_master == SSHCTL_MASTER_YES) 493 options.control_master = SSHCTL_MASTER_ASK; 494 else 495 options.control_master = SSHCTL_MASTER_YES; 496 break; 497 case 'p': 498 options.port = a2port(optarg); 499 if (options.port <= 0) { 500 fprintf(stderr, "Bad port '%s'\n", optarg); 501 exit(255); 502 } 503 break; 504 case 'l': 505 options.user = optarg; 506 break; 507 508 case 'L': 509 if (parse_forward(&fwd, optarg, 0, 0)) 510 add_local_forward(&options, &fwd); 511 else { 512 fprintf(stderr, 513 "Bad local forwarding specification '%s'\n", 514 optarg); 515 exit(255); 516 } 517 break; 518 519 case 'R': 520 if (parse_forward(&fwd, optarg, 0, 1)) { 521 add_remote_forward(&options, &fwd); 522 } else { 523 fprintf(stderr, 524 "Bad remote forwarding specification " 525 "'%s'\n", optarg); 526 exit(255); 527 } 528 break; 529 530 case 'D': 531 if (parse_forward(&fwd, optarg, 1, 0)) { 532 add_local_forward(&options, &fwd); 533 } else { 534 fprintf(stderr, 535 "Bad dynamic forwarding specification " 536 "'%s'\n", optarg); 537 exit(255); 538 } 539 break; 540 541 case 'C': 542 options.compression = 1; 543 break; 544 case 'N': 545 no_shell_flag = 1; 546 no_tty_flag = 1; 547 break; 548 case 'T': 549 no_tty_flag = 1; 550 break; 551 case 'o': 552 dummy = 1; 553 line = xstrdup(optarg); 554 if (process_config_line(&options, host ? host : "", 555 line, "command-line", 0, &dummy) != 0) 556 exit(255); 557 xfree(line); 558 break; 559 case 's': 560 subsystem_flag = 1; 561 break; 562 case 'S': 563 if (options.control_path != NULL) 564 free(options.control_path); 565 options.control_path = xstrdup(optarg); 566 break; 567 case 'b': 568 options.bind_address = optarg; 569 break; 570 case 'F': 571 config = optarg; 572 break; 573 default: 574 usage(); 575 } 576 } 577 578 ac -= optind; 579 av += optind; 580 581 if (ac > 0 && !host) { 582 if (strrchr(*av, '@')) { 583 p = xstrdup(*av); 584 cp = strrchr(p, '@'); 585 if (cp == NULL || cp == p) 586 usage(); 587 options.user = p; 588 *cp = '\0'; 589 host = ++cp; 590 } else 591 host = *av; 592 if (ac > 1) { 593 optind = optreset = 1; 594 goto again; 595 } 596 ac--, av++; 597 } 598 599 /* Check that we got a host name. */ 600 if (!host) 601 usage(); 602 603 SSLeay_add_all_algorithms(); 604 ERR_load_crypto_strings(); 605 606 /* Initialize the command to execute on remote host. */ 607 buffer_init(&command); 608 609 /* 610 * Save the command to execute on the remote host in a buffer. There 611 * is no limit on the length of the command, except by the maximum 612 * packet size. Also sets the tty flag if there is no command. 613 */ 614 if (!ac) { 615 /* No command specified - execute shell on a tty. */ 616 tty_flag = 1; 617 if (subsystem_flag) { 618 fprintf(stderr, 619 "You must specify a subsystem to invoke.\n"); 620 usage(); 621 } 622 } else { 623 /* A command has been specified. Store it into the buffer. */ 624 for (i = 0; i < ac; i++) { 625 if (i) 626 buffer_append(&command, " ", 1); 627 buffer_append(&command, av[i], strlen(av[i])); 628 } 629 } 630 631 /* Cannot fork to background if no command. */ 632 if (fork_after_authentication_flag && buffer_len(&command) == 0 && 633 !no_shell_flag) 634 fatal("Cannot fork into background without a command " 635 "to execute."); 636 637 /* Allocate a tty by default if no command specified. */ 638 if (buffer_len(&command) == 0) 639 tty_flag = 1; 640 641 /* Force no tty */ 642 if (no_tty_flag || muxclient_command != 0) 643 tty_flag = 0; 644 /* Do not allocate a tty if stdin is not a tty. */ 645 if ((!isatty(fileno(stdin)) || stdin_null_flag) && !force_tty_flag) { 646 if (tty_flag) 647 logit("Pseudo-terminal will not be allocated because " 648 "stdin is not a terminal."); 649 tty_flag = 0; 650 } 651 652 /* 653 * Initialize "log" output. Since we are the client all output 654 * actually goes to stderr. 655 */ 656 log_init(argv0, 657 options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level, 658 SYSLOG_FACILITY_USER, !use_syslog); 659 660 /* 661 * Read per-user configuration file. Ignore the system wide config 662 * file if the user specifies a config file on the command line. 663 */ 664 if (config != NULL) { 665 if (!read_config_file(config, host, &options, 0)) 666 fatal("Can't open user config file %.100s: " 667 "%.100s", config, strerror(errno)); 668 } else { 669 r = snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir, 670 _PATH_SSH_USER_CONFFILE); 671 if (r > 0 && (size_t)r < sizeof(buf)) 672 (void)read_config_file(buf, host, &options, 1); 673 674 /* Read systemwide configuration file after use config. */ 675 (void)read_config_file(_PATH_HOST_CONFIG_FILE, host, 676 &options, 0); 677 } 678 679 /* Fill configuration defaults. */ 680 fill_default_options(&options); 681 682 channel_set_af(options.address_family); 683 684 /* reinit */ 685 log_init(argv0, options.log_level, SYSLOG_FACILITY_USER, !use_syslog); 686 687 seed_rng(); 688 689 if (options.user == NULL) 690 options.user = xstrdup(pw->pw_name); 691 692 /* Get default port if port has not been set. */ 693 if (options.port == 0) { 694 sp = getservbyname(SSH_SERVICE_NAME, "tcp"); 695 options.port = sp ? ntohs(sp->s_port) : SSH_DEFAULT_PORT; 696 } 697 698 if (options.hostname != NULL) { 699 host = percent_expand(options.hostname, 700 "h", host, (char *)NULL); 701 } 702 703 if (options.local_command != NULL) { 704 char thishost[NI_MAXHOST]; 705 706 if (gethostname(thishost, sizeof(thishost)) == -1) 707 fatal("gethostname: %s", strerror(errno)); 708 snprintf(buf, sizeof(buf), "%d", options.port); 709 debug3("expanding LocalCommand: %s", options.local_command); 710 cp = options.local_command; 711 options.local_command = percent_expand(cp, "d", pw->pw_dir, 712 "h", host, "l", thishost, "n", host, "r", options.user, 713 "p", buf, "u", pw->pw_name, (char *)NULL); 714 debug3("expanded LocalCommand: %s", options.local_command); 715 xfree(cp); 716 } 717 718 /* Find canonic host name. */ 719 if (strchr(host, '.') == 0) { 720 struct addrinfo hints; 721 struct addrinfo *ai = NULL; 722 int errgai; 723 memset(&hints, 0, sizeof(hints)); 724 hints.ai_family = options.address_family; 725 hints.ai_flags = AI_CANONNAME; 726 hints.ai_socktype = SOCK_STREAM; 727 errgai = getaddrinfo(host, NULL, &hints, &ai); 728 if (errgai == 0) { 729 if (ai->ai_canonname != NULL) 730 host = xstrdup(ai->ai_canonname); 731 freeaddrinfo(ai); 732 } 733 } 734 735 /* force lowercase for hostkey matching */ 736 if (options.host_key_alias != NULL) { 737 for (p = options.host_key_alias; *p; p++) 738 if (isupper(*p)) 739 *p = (char)tolower(*p); 740 } 741 742 if (options.proxy_command != NULL && 743 strcmp(options.proxy_command, "none") == 0) { 744 xfree(options.proxy_command); 745 options.proxy_command = NULL; 746 } 747 if (options.control_path != NULL && 748 strcmp(options.control_path, "none") == 0) { 749 xfree(options.control_path); 750 options.control_path = NULL; 751 } 752 753 if (options.control_path != NULL) { 754 char thishost[NI_MAXHOST]; 755 756 if (gethostname(thishost, sizeof(thishost)) == -1) 757 fatal("gethostname: %s", strerror(errno)); 758 snprintf(buf, sizeof(buf), "%d", options.port); 759 cp = tilde_expand_filename(options.control_path, 760 original_real_uid); 761 xfree(options.control_path); 762 options.control_path = percent_expand(cp, "p", buf, "h", host, 763 "r", options.user, "l", thishost, (char *)NULL); 764 xfree(cp); 765 } 766 if (muxclient_command != 0 && options.control_path == NULL) 767 fatal("No ControlPath specified for \"-O\" command"); 768 if (options.control_path != NULL) 769 muxclient(options.control_path); 770 771 timeout_ms = options.connection_timeout * 1000; 772 773 /* Open a connection to the remote host. */ 774 if (ssh_connect(host, &hostaddr, options.port, 775 options.address_family, options.connection_attempts, &timeout_ms, 776 options.tcp_keep_alive, 777 #ifdef HAVE_CYGWIN 778 options.use_privileged_port, 779 #else 780 original_effective_uid == 0 && options.use_privileged_port, 781 #endif 782 options.proxy_command) != 0) 783 exit(255); 784 785 if (timeout_ms > 0) 786 debug3("timeout: %d ms remain after connect", timeout_ms); 787 788 /* 789 * If we successfully made the connection, load the host private key 790 * in case we will need it later for combined rsa-rhosts 791 * authentication. This must be done before releasing extra 792 * privileges, because the file is only readable by root. 793 * If we cannot access the private keys, load the public keys 794 * instead and try to execute the ssh-keysign helper instead. 795 */ 796 sensitive_data.nkeys = 0; 797 sensitive_data.keys = NULL; 798 sensitive_data.external_keysign = 0; 799 if (options.rhosts_rsa_authentication || 800 options.hostbased_authentication) { 801 sensitive_data.nkeys = 5; 802 sensitive_data.keys = xcalloc(sensitive_data.nkeys, 803 sizeof(Key)); 804 805 PRIV_START; 806 sensitive_data.keys[0] = key_load_private_type(KEY_RSA1, 807 _PATH_HOST_KEY_FILE, "", NULL, NULL); 808 sensitive_data.keys[1] = key_load_private_cert(KEY_DSA, 809 _PATH_HOST_DSA_KEY_FILE, "", NULL); 810 sensitive_data.keys[2] = key_load_private_cert(KEY_RSA, 811 _PATH_HOST_RSA_KEY_FILE, "", NULL); 812 sensitive_data.keys[3] = key_load_private_type(KEY_DSA, 813 _PATH_HOST_DSA_KEY_FILE, "", NULL, NULL); 814 sensitive_data.keys[4] = key_load_private_type(KEY_RSA, 815 _PATH_HOST_RSA_KEY_FILE, "", NULL, NULL); 816 PRIV_END; 817 818 if (options.hostbased_authentication == 1 && 819 sensitive_data.keys[0] == NULL && 820 sensitive_data.keys[3] == NULL && 821 sensitive_data.keys[4] == NULL) { 822 sensitive_data.keys[1] = key_load_cert( 823 _PATH_HOST_DSA_KEY_FILE); 824 sensitive_data.keys[2] = key_load_cert( 825 _PATH_HOST_RSA_KEY_FILE); 826 sensitive_data.keys[3] = key_load_public( 827 _PATH_HOST_DSA_KEY_FILE, NULL); 828 sensitive_data.keys[4] = key_load_public( 829 _PATH_HOST_RSA_KEY_FILE, NULL); 830 sensitive_data.external_keysign = 1; 831 } 832 } 833 /* 834 * Get rid of any extra privileges that we may have. We will no 835 * longer need them. Also, extra privileges could make it very hard 836 * to read identity files and other non-world-readable files from the 837 * user's home directory if it happens to be on a NFS volume where 838 * root is mapped to nobody. 839 */ 840 if (original_effective_uid == 0) { 841 PRIV_START; 842 permanently_set_uid(pw); 843 } 844 845 /* 846 * Now that we are back to our own permissions, create ~/.ssh 847 * directory if it doesn't already exist. 848 */ 849 r = snprintf(buf, sizeof buf, "%s%s%s", pw->pw_dir, 850 strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR); 851 if (r > 0 && (size_t)r < sizeof(buf) && stat(buf, &st) < 0) 852 if (mkdir(buf, 0700) < 0) 853 error("Could not create directory '%.200s'.", buf); 854 855 /* load options.identity_files */ 856 load_public_identity_files(); 857 858 /* Expand ~ in known host file names. */ 859 /* XXX mem-leaks: */ 860 options.system_hostfile = 861 tilde_expand_filename(options.system_hostfile, original_real_uid); 862 options.user_hostfile = 863 tilde_expand_filename(options.user_hostfile, original_real_uid); 864 options.system_hostfile2 = 865 tilde_expand_filename(options.system_hostfile2, original_real_uid); 866 options.user_hostfile2 = 867 tilde_expand_filename(options.user_hostfile2, original_real_uid); 868 869 signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */ 870 871 /* Log into the remote system. Never returns if the login fails. */ 872 ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr, 873 pw, timeout_ms); 874 875 if (packet_connection_is_on_socket()) { 876 verbose("Authenticated to %s ([%s]:%d).", host, 877 get_remote_ipaddr(), get_remote_port()); 878 } else { 879 verbose("Authenticated to %s (via proxy).", host); 880 } 881 882 /* We no longer need the private host keys. Clear them now. */ 883 if (sensitive_data.nkeys != 0) { 884 for (i = 0; i < sensitive_data.nkeys; i++) { 885 if (sensitive_data.keys[i] != NULL) { 886 /* Destroys contents safely */ 887 debug3("clear hostkey %d", i); 888 key_free(sensitive_data.keys[i]); 889 sensitive_data.keys[i] = NULL; 890 } 891 } 892 xfree(sensitive_data.keys); 893 } 894 for (i = 0; i < options.num_identity_files; i++) { 895 if (options.identity_files[i]) { 896 xfree(options.identity_files[i]); 897 options.identity_files[i] = NULL; 898 } 899 if (options.identity_keys[i]) { 900 key_free(options.identity_keys[i]); 901 options.identity_keys[i] = NULL; 902 } 903 } 904 905 exit_status = compat20 ? ssh_session2() : ssh_session(); 906 packet_close(); 907 908 if (options.control_path != NULL && muxserver_sock != -1) 909 unlink(options.control_path); 910 911 /* 912 * Send SIGHUP to proxy command if used. We don't wait() in 913 * case it hangs and instead rely on init to reap the child 914 */ 915 if (proxy_command_pid > 1) 916 kill(proxy_command_pid, SIGHUP); 917 918 return exit_status; 919 } 920 921 static void 922 control_persist_detach(void) 923 { 924 pid_t pid; 925 int devnull; 926 927 debug("%s: backgrounding master process", __func__); 928 929 /* 930 * master (current process) into the background, and make the 931 * foreground process a client of the backgrounded master. 932 */ 933 switch ((pid = fork())) { 934 case -1: 935 fatal("%s: fork: %s", __func__, strerror(errno)); 936 case 0: 937 /* Child: master process continues mainloop */ 938 break; 939 default: 940 /* Parent: set up mux slave to connect to backgrounded master */ 941 debug2("%s: background process is %ld", __func__, (long)pid); 942 stdin_null_flag = ostdin_null_flag; 943 no_shell_flag = ono_shell_flag; 944 no_tty_flag = ono_tty_flag; 945 tty_flag = otty_flag; 946 close(muxserver_sock); 947 muxserver_sock = -1; 948 muxclient(options.control_path); 949 /* muxclient() doesn't return on success. */ 950 fatal("Failed to connect to new control master"); 951 } 952 if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) { 953 error("%s: open(\"/dev/null\"): %s", __func__, 954 strerror(errno)); 955 } else { 956 if (dup2(devnull, STDIN_FILENO) == -1 || 957 dup2(devnull, STDOUT_FILENO) == -1) 958 error("%s: dup2: %s", __func__, strerror(errno)); 959 if (devnull > STDERR_FILENO) 960 close(devnull); 961 } 962 } 963 964 /* Do fork() after authentication. Used by "ssh -f" */ 965 static void 966 fork_postauth(void) 967 { 968 if (need_controlpersist_detach) 969 control_persist_detach(); 970 debug("forking to background"); 971 fork_after_authentication_flag = 0; 972 if (daemon(1, 1) < 0) 973 fatal("daemon() failed: %.200s", strerror(errno)); 974 } 975 976 /* Callback for remote forward global requests */ 977 static void 978 ssh_confirm_remote_forward(int type, u_int32_t seq, void *ctxt) 979 { 980 Forward *rfwd = (Forward *)ctxt; 981 982 /* XXX verbose() on failure? */ 983 debug("remote forward %s for: listen %d, connect %s:%d", 984 type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure", 985 rfwd->listen_port, rfwd->connect_host, rfwd->connect_port); 986 if (type == SSH2_MSG_REQUEST_SUCCESS && rfwd->listen_port == 0) { 987 rfwd->allocated_port = packet_get_int(); 988 logit("Allocated port %u for remote forward to %s:%d", 989 rfwd->allocated_port, 990 rfwd->connect_host, rfwd->connect_port); 991 } 992 993 if (type == SSH2_MSG_REQUEST_FAILURE) { 994 if (options.exit_on_forward_failure) 995 fatal("Error: remote port forwarding failed for " 996 "listen port %d", rfwd->listen_port); 997 else 998 logit("Warning: remote port forwarding failed for " 999 "listen port %d", rfwd->listen_port); 1000 } 1001 if (++remote_forward_confirms_received == options.num_remote_forwards) { 1002 debug("All remote forwarding requests processed"); 1003 if (fork_after_authentication_flag) 1004 fork_postauth(); 1005 } 1006 } 1007 1008 static void 1009 client_cleanup_stdio_fwd(int id, void *arg) 1010 { 1011 debug("stdio forwarding: done"); 1012 cleanup_exit(0); 1013 } 1014 1015 static int 1016 client_setup_stdio_fwd(const char *host_to_connect, u_short port_to_connect) 1017 { 1018 Channel *c; 1019 int in, out; 1020 1021 debug3("client_setup_stdio_fwd %s:%d", host_to_connect, 1022 port_to_connect); 1023 1024 in = dup(STDIN_FILENO); 1025 out = dup(STDOUT_FILENO); 1026 if (in < 0 || out < 0) 1027 fatal("channel_connect_stdio_fwd: dup() in/out failed"); 1028 1029 if ((c = channel_connect_stdio_fwd(host_to_connect, port_to_connect, 1030 in, out)) == NULL) 1031 return 0; 1032 channel_register_cleanup(c->self, client_cleanup_stdio_fwd, 0); 1033 return 1; 1034 } 1035 1036 static void 1037 ssh_init_forwarding(void) 1038 { 1039 int success = 0; 1040 int i; 1041 1042 if (stdio_forward_host != NULL) { 1043 if (!compat20) { 1044 fatal("stdio forwarding require Protocol 2"); 1045 } 1046 if (!client_setup_stdio_fwd(stdio_forward_host, 1047 stdio_forward_port)) 1048 fatal("Failed to connect in stdio forward mode."); 1049 } 1050 1051 /* Initiate local TCP/IP port forwardings. */ 1052 for (i = 0; i < options.num_local_forwards; i++) { 1053 debug("Local connections to %.200s:%d forwarded to remote " 1054 "address %.200s:%d", 1055 (options.local_forwards[i].listen_host == NULL) ? 1056 (options.gateway_ports ? "*" : "LOCALHOST") : 1057 options.local_forwards[i].listen_host, 1058 options.local_forwards[i].listen_port, 1059 options.local_forwards[i].connect_host, 1060 options.local_forwards[i].connect_port); 1061 success += channel_setup_local_fwd_listener( 1062 options.local_forwards[i].listen_host, 1063 options.local_forwards[i].listen_port, 1064 options.local_forwards[i].connect_host, 1065 options.local_forwards[i].connect_port, 1066 options.gateway_ports); 1067 } 1068 if (i > 0 && success != i && options.exit_on_forward_failure) 1069 fatal("Could not request local forwarding."); 1070 if (i > 0 && success == 0) 1071 error("Could not request local forwarding."); 1072 1073 /* Initiate remote TCP/IP port forwardings. */ 1074 for (i = 0; i < options.num_remote_forwards; i++) { 1075 debug("Remote connections from %.200s:%d forwarded to " 1076 "local address %.200s:%d", 1077 (options.remote_forwards[i].listen_host == NULL) ? 1078 "LOCALHOST" : options.remote_forwards[i].listen_host, 1079 options.remote_forwards[i].listen_port, 1080 options.remote_forwards[i].connect_host, 1081 options.remote_forwards[i].connect_port); 1082 if (channel_request_remote_forwarding( 1083 options.remote_forwards[i].listen_host, 1084 options.remote_forwards[i].listen_port, 1085 options.remote_forwards[i].connect_host, 1086 options.remote_forwards[i].connect_port) < 0) { 1087 if (options.exit_on_forward_failure) 1088 fatal("Could not request remote forwarding."); 1089 else 1090 logit("Warning: Could not request remote " 1091 "forwarding."); 1092 } 1093 client_register_global_confirm(ssh_confirm_remote_forward, 1094 &options.remote_forwards[i]); 1095 } 1096 1097 /* Initiate tunnel forwarding. */ 1098 if (options.tun_open != SSH_TUNMODE_NO) { 1099 if (client_request_tun_fwd(options.tun_open, 1100 options.tun_local, options.tun_remote) == -1) { 1101 if (options.exit_on_forward_failure) 1102 fatal("Could not request tunnel forwarding."); 1103 else 1104 error("Could not request tunnel forwarding."); 1105 } 1106 } 1107 } 1108 1109 static void 1110 check_agent_present(void) 1111 { 1112 if (options.forward_agent) { 1113 /* Clear agent forwarding if we don't have an agent. */ 1114 if (!ssh_agent_present()) 1115 options.forward_agent = 0; 1116 } 1117 } 1118 1119 static int 1120 ssh_session(void) 1121 { 1122 int type; 1123 int interactive = 0; 1124 int have_tty = 0; 1125 struct winsize ws; 1126 char *cp; 1127 const char *display; 1128 1129 /* Enable compression if requested. */ 1130 if (options.compression) { 1131 debug("Requesting compression at level %d.", 1132 options.compression_level); 1133 1134 if (options.compression_level < 1 || 1135 options.compression_level > 9) 1136 fatal("Compression level must be from 1 (fast) to " 1137 "9 (slow, best)."); 1138 1139 /* Send the request. */ 1140 packet_start(SSH_CMSG_REQUEST_COMPRESSION); 1141 packet_put_int(options.compression_level); 1142 packet_send(); 1143 packet_write_wait(); 1144 type = packet_read(); 1145 if (type == SSH_SMSG_SUCCESS) 1146 packet_start_compression(options.compression_level); 1147 else if (type == SSH_SMSG_FAILURE) 1148 logit("Warning: Remote host refused compression."); 1149 else 1150 packet_disconnect("Protocol error waiting for " 1151 "compression response."); 1152 } 1153 /* Allocate a pseudo tty if appropriate. */ 1154 if (tty_flag) { 1155 debug("Requesting pty."); 1156 1157 /* Start the packet. */ 1158 packet_start(SSH_CMSG_REQUEST_PTY); 1159 1160 /* Store TERM in the packet. There is no limit on the 1161 length of the string. */ 1162 cp = getenv("TERM"); 1163 if (!cp) 1164 cp = ""; 1165 packet_put_cstring(cp); 1166 1167 /* Store window size in the packet. */ 1168 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0) 1169 memset(&ws, 0, sizeof(ws)); 1170 packet_put_int((u_int)ws.ws_row); 1171 packet_put_int((u_int)ws.ws_col); 1172 packet_put_int((u_int)ws.ws_xpixel); 1173 packet_put_int((u_int)ws.ws_ypixel); 1174 1175 /* Store tty modes in the packet. */ 1176 tty_make_modes(fileno(stdin), NULL); 1177 1178 /* Send the packet, and wait for it to leave. */ 1179 packet_send(); 1180 packet_write_wait(); 1181 1182 /* Read response from the server. */ 1183 type = packet_read(); 1184 if (type == SSH_SMSG_SUCCESS) { 1185 interactive = 1; 1186 have_tty = 1; 1187 } else if (type == SSH_SMSG_FAILURE) 1188 logit("Warning: Remote host failed or refused to " 1189 "allocate a pseudo tty."); 1190 else 1191 packet_disconnect("Protocol error waiting for pty " 1192 "request response."); 1193 } 1194 /* Request X11 forwarding if enabled and DISPLAY is set. */ 1195 display = getenv("DISPLAY"); 1196 if (options.forward_x11 && display != NULL) { 1197 char *proto, *data; 1198 /* Get reasonable local authentication information. */ 1199 client_x11_get_proto(display, options.xauth_location, 1200 options.forward_x11_trusted, 1201 options.forward_x11_timeout, 1202 &proto, &data); 1203 /* Request forwarding with authentication spoofing. */ 1204 debug("Requesting X11 forwarding with authentication " 1205 "spoofing."); 1206 x11_request_forwarding_with_spoofing(0, display, proto, data); 1207 1208 /* Read response from the server. */ 1209 type = packet_read(); 1210 if (type == SSH_SMSG_SUCCESS) { 1211 interactive = 1; 1212 } else if (type == SSH_SMSG_FAILURE) { 1213 logit("Warning: Remote host denied X11 forwarding."); 1214 } else { 1215 packet_disconnect("Protocol error waiting for X11 " 1216 "forwarding"); 1217 } 1218 } 1219 /* Tell the packet module whether this is an interactive session. */ 1220 packet_set_interactive(interactive); 1221 1222 /* Request authentication agent forwarding if appropriate. */ 1223 check_agent_present(); 1224 1225 if (options.forward_agent) { 1226 debug("Requesting authentication agent forwarding."); 1227 auth_request_forwarding(); 1228 1229 /* Read response from the server. */ 1230 type = packet_read(); 1231 packet_check_eom(); 1232 if (type != SSH_SMSG_SUCCESS) 1233 logit("Warning: Remote host denied authentication agent forwarding."); 1234 } 1235 1236 /* Initiate port forwardings. */ 1237 ssh_init_forwarding(); 1238 1239 /* Execute a local command */ 1240 if (options.local_command != NULL && 1241 options.permit_local_command) 1242 ssh_local_cmd(options.local_command); 1243 1244 /* 1245 * If requested and we are not interested in replies to remote 1246 * forwarding requests, then let ssh continue in the background. 1247 */ 1248 if (fork_after_authentication_flag) { 1249 if (options.exit_on_forward_failure && 1250 options.num_remote_forwards > 0) { 1251 debug("deferring postauth fork until remote forward " 1252 "confirmation received"); 1253 } else 1254 fork_postauth(); 1255 } 1256 1257 /* 1258 * If a command was specified on the command line, execute the 1259 * command now. Otherwise request the server to start a shell. 1260 */ 1261 if (buffer_len(&command) > 0) { 1262 int len = buffer_len(&command); 1263 if (len > 900) 1264 len = 900; 1265 debug("Sending command: %.*s", len, 1266 (u_char *)buffer_ptr(&command)); 1267 packet_start(SSH_CMSG_EXEC_CMD); 1268 packet_put_string(buffer_ptr(&command), buffer_len(&command)); 1269 packet_send(); 1270 packet_write_wait(); 1271 } else { 1272 debug("Requesting shell."); 1273 packet_start(SSH_CMSG_EXEC_SHELL); 1274 packet_send(); 1275 packet_write_wait(); 1276 } 1277 1278 /* Enter the interactive session. */ 1279 return client_loop(have_tty, tty_flag ? 1280 options.escape_char : SSH_ESCAPECHAR_NONE, 0); 1281 } 1282 1283 /* request pty/x11/agent/tcpfwd/shell for channel */ 1284 static void 1285 ssh_session2_setup(int id, int success, void *arg) 1286 { 1287 extern char **environ; 1288 const char *display; 1289 int interactive = tty_flag; 1290 1291 if (!success) 1292 return; /* No need for error message, channels code sens one */ 1293 1294 display = getenv("DISPLAY"); 1295 if (options.forward_x11 && display != NULL) { 1296 char *proto, *data; 1297 /* Get reasonable local authentication information. */ 1298 client_x11_get_proto(display, options.xauth_location, 1299 options.forward_x11_trusted, 1300 options.forward_x11_timeout, &proto, &data); 1301 /* Request forwarding with authentication spoofing. */ 1302 debug("Requesting X11 forwarding with authentication " 1303 "spoofing."); 1304 x11_request_forwarding_with_spoofing(id, display, proto, data); 1305 interactive = 1; 1306 /* XXX wait for reply */ 1307 } 1308 1309 check_agent_present(); 1310 if (options.forward_agent) { 1311 debug("Requesting authentication agent forwarding."); 1312 channel_request_start(id, "auth-agent-req@openssh.com", 0); 1313 packet_send(); 1314 } 1315 1316 client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"), 1317 NULL, fileno(stdin), &command, environ); 1318 1319 packet_set_interactive(interactive); 1320 } 1321 1322 /* open new channel for a session */ 1323 static int 1324 ssh_session2_open(void) 1325 { 1326 Channel *c; 1327 int window, packetmax, in, out, err; 1328 1329 if (stdin_null_flag) { 1330 in = open(_PATH_DEVNULL, O_RDONLY); 1331 } else { 1332 in = dup(STDIN_FILENO); 1333 } 1334 out = dup(STDOUT_FILENO); 1335 err = dup(STDERR_FILENO); 1336 1337 if (in < 0 || out < 0 || err < 0) 1338 fatal("dup() in/out/err failed"); 1339 1340 /* enable nonblocking unless tty */ 1341 if (!isatty(in)) 1342 set_nonblock(in); 1343 if (!isatty(out)) 1344 set_nonblock(out); 1345 if (!isatty(err)) 1346 set_nonblock(err); 1347 1348 window = CHAN_SES_WINDOW_DEFAULT; 1349 packetmax = CHAN_SES_PACKET_DEFAULT; 1350 if (tty_flag) { 1351 window >>= 1; 1352 packetmax >>= 1; 1353 } 1354 c = channel_new( 1355 "session", SSH_CHANNEL_OPENING, in, out, err, 1356 window, packetmax, CHAN_EXTENDED_WRITE, 1357 "client-session", /*nonblock*/0); 1358 1359 debug3("ssh_session2_open: channel_new: %d", c->self); 1360 1361 channel_send_open(c->self); 1362 if (!no_shell_flag) 1363 channel_register_open_confirm(c->self, 1364 ssh_session2_setup, NULL); 1365 1366 return c->self; 1367 } 1368 1369 static int 1370 ssh_session2(void) 1371 { 1372 int id = -1; 1373 1374 /* XXX should be pre-session */ 1375 ssh_init_forwarding(); 1376 1377 /* Start listening for multiplex clients */ 1378 muxserver_listen(); 1379 1380 /* 1381 * If we are in control persist mode, then prepare to background 1382 * ourselves and have a foreground client attach as a control 1383 * slave. NB. we must save copies of the flags that we override for 1384 * the backgrounding, since we defer attachment of the slave until 1385 * after the connection is fully established (in particular, 1386 * async rfwd replies have been received for ExitOnForwardFailure). 1387 */ 1388 if (options.control_persist && muxserver_sock != -1) { 1389 ostdin_null_flag = stdin_null_flag; 1390 ono_shell_flag = no_shell_flag; 1391 ono_tty_flag = no_tty_flag; 1392 otty_flag = tty_flag; 1393 stdin_null_flag = 1; 1394 no_shell_flag = 1; 1395 no_tty_flag = 1; 1396 tty_flag = 0; 1397 if (!fork_after_authentication_flag) 1398 need_controlpersist_detach = 1; 1399 fork_after_authentication_flag = 1; 1400 } 1401 1402 if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN)) 1403 id = ssh_session2_open(); 1404 1405 /* If we don't expect to open a new session, then disallow it */ 1406 if (options.control_master == SSHCTL_MASTER_NO && 1407 (datafellows & SSH_NEW_OPENSSH)) { 1408 debug("Requesting no-more-sessions@openssh.com"); 1409 packet_start(SSH2_MSG_GLOBAL_REQUEST); 1410 packet_put_cstring("no-more-sessions@openssh.com"); 1411 packet_put_char(0); 1412 packet_send(); 1413 } 1414 1415 /* Execute a local command */ 1416 if (options.local_command != NULL && 1417 options.permit_local_command) 1418 ssh_local_cmd(options.local_command); 1419 1420 /* 1421 * If requested and we are not interested in replies to remote 1422 * forwarding requests, then let ssh continue in the background. 1423 */ 1424 if (fork_after_authentication_flag) { 1425 if (options.exit_on_forward_failure && 1426 options.num_remote_forwards > 0) { 1427 debug("deferring postauth fork until remote forward " 1428 "confirmation received"); 1429 } else 1430 fork_postauth(); 1431 } 1432 1433 if (options.use_roaming) 1434 request_roaming(); 1435 1436 return client_loop(tty_flag, tty_flag ? 1437 options.escape_char : SSH_ESCAPECHAR_NONE, id); 1438 } 1439 1440 static void 1441 load_public_identity_files(void) 1442 { 1443 char *filename, *cp, thishost[NI_MAXHOST]; 1444 char *pwdir = NULL, *pwname = NULL; 1445 int i = 0; 1446 Key *public; 1447 struct passwd *pw; 1448 u_int n_ids; 1449 char *identity_files[SSH_MAX_IDENTITY_FILES]; 1450 Key *identity_keys[SSH_MAX_IDENTITY_FILES]; 1451 #ifdef ENABLE_PKCS11 1452 Key **keys; 1453 int nkeys; 1454 #endif /* PKCS11 */ 1455 1456 n_ids = 0; 1457 bzero(identity_files, sizeof(identity_files)); 1458 bzero(identity_keys, sizeof(identity_keys)); 1459 1460 #ifdef ENABLE_PKCS11 1461 if (options.pkcs11_provider != NULL && 1462 options.num_identity_files < SSH_MAX_IDENTITY_FILES && 1463 (pkcs11_init(!options.batch_mode) == 0) && 1464 (nkeys = pkcs11_add_provider(options.pkcs11_provider, NULL, 1465 &keys)) > 0) { 1466 for (i = 0; i < nkeys; i++) { 1467 if (n_ids >= SSH_MAX_IDENTITY_FILES) { 1468 key_free(keys[i]); 1469 continue; 1470 } 1471 identity_keys[n_ids] = keys[i]; 1472 identity_files[n_ids] = 1473 xstrdup(options.pkcs11_provider); /* XXX */ 1474 n_ids++; 1475 } 1476 xfree(keys); 1477 } 1478 #endif /* ENABLE_PKCS11 */ 1479 if ((pw = getpwuid(original_real_uid)) == NULL) 1480 fatal("load_public_identity_files: getpwuid failed"); 1481 pwname = xstrdup(pw->pw_name); 1482 pwdir = xstrdup(pw->pw_dir); 1483 if (gethostname(thishost, sizeof(thishost)) == -1) 1484 fatal("load_public_identity_files: gethostname: %s", 1485 strerror(errno)); 1486 for (i = 0; i < options.num_identity_files; i++) { 1487 if (n_ids >= SSH_MAX_IDENTITY_FILES) { 1488 xfree(options.identity_files[i]); 1489 continue; 1490 } 1491 cp = tilde_expand_filename(options.identity_files[i], 1492 original_real_uid); 1493 filename = percent_expand(cp, "d", pwdir, 1494 "u", pwname, "l", thishost, "h", host, 1495 "r", options.user, (char *)NULL); 1496 xfree(cp); 1497 public = key_load_public(filename, NULL); 1498 debug("identity file %s type %d", filename, 1499 public ? public->type : -1); 1500 xfree(options.identity_files[i]); 1501 identity_files[n_ids] = filename; 1502 identity_keys[n_ids] = public; 1503 1504 if (++n_ids >= SSH_MAX_IDENTITY_FILES) 1505 continue; 1506 1507 /* Try to add the certificate variant too */ 1508 xasprintf(&cp, "%s-cert", filename); 1509 public = key_load_public(cp, NULL); 1510 debug("identity file %s type %d", cp, 1511 public ? public->type : -1); 1512 if (public == NULL) { 1513 xfree(cp); 1514 continue; 1515 } 1516 if (!key_is_cert(public)) { 1517 debug("%s: key %s type %s is not a certificate", 1518 __func__, cp, key_type(public)); 1519 key_free(public); 1520 xfree(cp); 1521 continue; 1522 } 1523 identity_keys[n_ids] = public; 1524 /* point to the original path, most likely the private key */ 1525 identity_files[n_ids] = xstrdup(filename); 1526 n_ids++; 1527 } 1528 options.num_identity_files = n_ids; 1529 memcpy(options.identity_files, identity_files, sizeof(identity_files)); 1530 memcpy(options.identity_keys, identity_keys, sizeof(identity_keys)); 1531 1532 bzero(pwname, strlen(pwname)); 1533 xfree(pwname); 1534 bzero(pwdir, strlen(pwdir)); 1535 xfree(pwdir); 1536 } 1537