crypto/openssh/ssh.c

   1 /* $OpenBSD: ssh.c,v 1.335 2010/02/26 20:29:54 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 "compat.h"
  84 #include "cipher.h"
  85 #include "packet.h"
  86 #include "buffer.h"
  87 #include "channels.h"
  88 #include "key.h"
  89 #include "authfd.h"
  90 #include "authfile.h"
  91 #include "pathnames.h"
  92 #include "dispatch.h"
  93 #include "clientloop.h"
  94 #include "log.h"
  95 #include "readconf.h"
  96 #include "sshconnect.h"
  97 #include "misc.h"
  98 #include "kex.h"
  99 #include "mac.h"
 100 #include "sshpty.h"
 101 #include "match.h"
 102 #include "msg.h"
 103 #include "uidswap.h"
 104 #include "roaming.h"
 105 #include "version.h"
 106
 107 #ifdef ENABLE_PKCS11
 108 #include "ssh-pkcs11.h"
 109 #endif
 110
 111 extern char *__progname;
 112
 113 /* Flag indicating whether debug mode is on.  May be set on the command line. */
 114 int debug_flag = 0;
 115
 116 /* Flag indicating whether a tty should be allocated */
 117 int tty_flag = 0;
 118 int no_tty_flag = 0;
 119 int force_tty_flag = 0;
 120
 121 /* don't exec a shell */
 122 int no_shell_flag = 0;
 123
 124 /*
 125  * Flag indicating that nothing should be read from stdin.  This can be set
 126  * on the command line.
 127  */
 128 int stdin_null_flag = 0;
 129
 130 /*
 131  * Flag indicating that ssh should fork after authentication.  This is useful
 132  * so that the passphrase can be entered manually, and then ssh goes to the
 133  * background.
 134  */
 135 int fork_after_authentication_flag = 0;
 136
 137 /* forward stdio to remote host and port */
 138 char *stdio_forward_host = NULL;
 139 int stdio_forward_port = 0;
 140
 141 /*
 142  * General data structure for command line options and options configurable
 143  * in configuration files.  See readconf.h.
 144  */
 145 Options options;
 146
 147 /* optional user configfile */
 148 char *config = NULL;
 149
 150 /*
 151  * Name of the host we are connecting to.  This is the name given on the
 152  * command line, or the HostName specified for the user-supplied name in a
 153  * configuration file.
 154  */
 155 char *host;
 156
 157 /* socket address the host resolves to */
 158 struct sockaddr_storage hostaddr;
 159
 160 /* Private host keys. */
 161 Sensitive sensitive_data;
 162
 163 /* Original real UID. */
 164 uid_t original_real_uid;
 165 uid_t original_effective_uid;
 166
 167 /* command to be executed */
 168 Buffer command;
 169
 170 /* Should we execute a command or invoke a subsystem? */
 171 int subsystem_flag = 0;
 172
 173 /* # of replies received for global requests */
 174 static int remote_forward_confirms_received = 0;
 175
 176 /* pid of proxycommand child process */
 177 pid_t proxy_command_pid = 0;
 178
 179 /* mux.c */
 180 extern int muxserver_sock;
 181 extern u_int muxclient_command;
 182
 183 /* Prints a help message to the user.  This function never returns. */
 184
 185 static void
 186 usage(void)
 187 {
 188         fprintf(stderr,
 189 "usage: ssh [-1246AaCfgKkMNnqsTtVvXxYy] [-b bind_address] [-c cipher_spec]\n"
 190 "           [-D [bind_address:]port] [-e escape_char] [-F configfile]\n"
 191 "           [-I pkcs11] [-i identity_file]\n"
 192 "           [-L [bind_address:]port:host:hostport]\n"
 193 "           [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n"
 194 "           [-R [bind_address:]port:host:hostport] [-S ctl_path]\n"
 195 "           [-W host:port] [-w local_tun[:remote_tun]]\n"
 196 "           [user@]hostname [command]\n"
 197         );
 198         exit(255);
 199 }
 200
 201 static int ssh_session(void);
 202 static int ssh_session2(void);
 203 static void load_public_identity_files(void);
 204
 205 /* from muxclient.c */
 206 void muxclient(const char *);
 207 void muxserver_listen(void);
 208
 209 /*
 210  * Main program for the ssh client.
 211  */
 212 int
 213 main(int ac, char **av)
 214 {
 215         int i, r, opt, exit_status, use_syslog;
 216         char *p, *cp, *line, *argv0, buf[MAXPATHLEN];
 217         struct stat st;
 218         struct passwd *pw;
 219         int dummy, timeout_ms;
 220         extern int optind, optreset;
 221         extern char *optarg;
 222         struct servent *sp;
 223         Forward fwd;
 224
 225         /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
 226         sanitise_stdfd();
 227
 228         __progname = ssh_get_progname(av[0]);
 229         init_rng();
 230
 231         /*
 232          * Save the original real uid.  It will be needed later (uid-swapping
 233          * may clobber the real uid).
 234          */
 235         original_real_uid = getuid();
 236         original_effective_uid = geteuid();
 237
 238         /*
 239          * Use uid-swapping to give up root privileges for the duration of
 240          * option processing.  We will re-instantiate the rights when we are
 241          * ready to create the privileged port, and will permanently drop
 242          * them when the port has been created (actually, when the connection
 243          * has been made, as we may need to create the port several times).
 244          */
 245         PRIV_END;
 246
 247 #ifdef HAVE_SETRLIMIT
 248         /* If we are installed setuid root be careful to not drop core. */
 249         if (original_real_uid != original_effective_uid) {
 250                 struct rlimit rlim;
 251                 rlim.rlim_cur = rlim.rlim_max = 0;
 252                 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
 253                         fatal("setrlimit failed: %.100s", strerror(errno));
 254         }
 255 #endif
 256         /* Get user data. */
 257         pw = getpwuid(original_real_uid);
 258         if (!pw) {
 259                 logit("You don't exist, go away!");
 260                 exit(255);
 261         }
 262         /* Take a copy of the returned structure. */
 263         pw = pwcopy(pw);
 264
 265         /*
 266          * Set our umask to something reasonable, as some files are created
 267          * with the default umask.  This will make them world-readable but
 268          * writable only by the owner, which is ok for all files for which we
 269          * don't set the modes explicitly.
 270          */
 271         umask(022);
 272
 273         /*
 274          * Initialize option structure to indicate that no values have been
 275          * set.
 276          */
 277         initialize_options(&options);
 278
 279         /* Parse command-line arguments. */
 280         host = NULL;
 281         use_syslog = 0;
 282         argv0 = av[0];
 283
 284  again:
 285         while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx"
 286             "ACD:F:I:KL:MNO:PR:S:TVw:W:XYy")) != -1) {
 287                 switch (opt) {
 288                 case '1':
 289                         options.protocol = SSH_PROTO_1;
 290                         break;
 291                 case '2':
 292                         options.protocol = SSH_PROTO_2;
 293                         break;
 294                 case '4':
 295                         options.address_family = AF_INET;
 296                         break;
 297                 case '6':
 298                         options.address_family = AF_INET6;
 299                         break;
 300                 case 'n':
 301                         stdin_null_flag = 1;
 302                         break;
 303                 case 'f':
 304                         fork_after_authentication_flag = 1;
 305                         stdin_null_flag = 1;
 306                         break;
 307                 case 'x':
 308                         options.forward_x11 = 0;
 309                         break;
 310                 case 'X':
 311                         options.forward_x11 = 1;
 312                         break;
 313                 case 'y':
 314                         use_syslog = 1;
 315                         break;
 316                 case 'Y':
 317                         options.forward_x11 = 1;
 318                         options.forward_x11_trusted = 1;
 319                         break;
 320                 case 'g':
 321                         options.gateway_ports = 1;
 322                         break;
 323                 case 'O':
 324                         if (stdio_forward_host != NULL)
 325                                 fatal("Cannot specify multiplexing "
 326                                     "command with -W");
 327                         else if (muxclient_command != 0)
 328                                 fatal("Multiplexing command already specified");
 329                         if (strcmp(optarg, "check") == 0)
 330                                 muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK;
 331                         else if (strcmp(optarg, "exit") == 0)
 332                                 muxclient_command = SSHMUX_COMMAND_TERMINATE;
 333                         else
 334                                 fatal("Invalid multiplex command.");
 335                         break;
 336                 case 'P':       /* deprecated */
 337                         options.use_privileged_port = 0;
 338                         break;
 339                 case 'a':
 340                         options.forward_agent = 0;
 341                         break;
 342                 case 'A':
 343                         options.forward_agent = 1;
 344                         break;
 345                 case 'k':
 346                         options.gss_deleg_creds = 0;
 347                         break;
 348                 case 'K':
 349                         options.gss_authentication = 1;
 350                         options.gss_deleg_creds = 1;
 351                         break;
 352                 case 'i':
 353                         if (stat(optarg, &st) < 0) {
 354                                 fprintf(stderr, "Warning: Identity file %s "
 355                                     "not accessible: %s.\n", optarg,
 356                                     strerror(errno));
 357                                 break;
 358                         }
 359                         if (options.num_identity_files >=
 360                             SSH_MAX_IDENTITY_FILES)
 361                                 fatal("Too many identity files specified "
 362                                     "(max %d)", SSH_MAX_IDENTITY_FILES);
 363                         options.identity_files[options.num_identity_files++] =
 364                             xstrdup(optarg);
 365                         break;
 366                 case 'I':
 367 #ifdef ENABLE_PKCS11
 368                         options.pkcs11_provider = xstrdup(optarg);
 369 #else
 370                         fprintf(stderr, "no support for PKCS#11.\n");
 371 #endif
 372                         break;
 373                 case 't':
 374                         if (tty_flag)
 375                                 force_tty_flag = 1;
 376                         tty_flag = 1;
 377                         break;
 378                 case 'v':
 379                         if (debug_flag == 0) {
 380                                 debug_flag = 1;
 381                                 options.log_level = SYSLOG_LEVEL_DEBUG1;
 382                         } else {
 383                                 if (options.log_level < SYSLOG_LEVEL_DEBUG3)
 384                                         options.log_level++;
 385                                 break;
 386                         }
 387                         /* FALLTHROUGH */
 388                 case 'V':
 389                         fprintf(stderr, "%s, %s\n",
 390                             SSH_RELEASE, SSLeay_version(SSLEAY_VERSION));
 391                         if (opt == 'V')
 392                                 exit(0);
 393                         break;
 394                 case 'w':
 395                         if (options.tun_open == -1)
 396                                 options.tun_open = SSH_TUNMODE_DEFAULT;
 397                         options.tun_local = a2tun(optarg, &options.tun_remote);
 398                         if (options.tun_local == SSH_TUNID_ERR) {
 399                                 fprintf(stderr,
 400                                     "Bad tun device '%s'\n", optarg);
 401                                 exit(255);
 402                         }
 403                         break;
 404                 case 'W':
 405                         if (stdio_forward_host != NULL)
 406                                 fatal("stdio forward already specified");
 407                         if (muxclient_command != 0)
 408                                 fatal("Cannot specify stdio forward with -O");
 409                         if (parse_forward(&fwd, optarg, 1, 0)) {
 410                                 stdio_forward_host = fwd.listen_host;
 411                                 stdio_forward_port = fwd.listen_port;
 412                                 xfree(fwd.connect_host);
 413                         } else {
 414                                 fprintf(stderr,
 415                                     "Bad stdio forwarding specification '%s'\n",
 416                                     optarg);
 417                                 exit(255);
 418                         }
 419                         no_tty_flag = 1;
 420                         no_shell_flag = 1;
 421                         options.clear_forwardings = 1;
 422                         options.exit_on_forward_failure = 1;
 423                         break;
 424                 case 'q':
 425                         options.log_level = SYSLOG_LEVEL_QUIET;
 426                         break;
 427                 case 'e':
 428                         if (optarg[0] == '^' && optarg[2] == 0 &&
 429                             (u_char) optarg[1] >= 64 &&
 430                             (u_char) optarg[1] < 128)
 431                                 options.escape_char = (u_char) optarg[1] & 31;
 432                         else if (strlen(optarg) == 1)
 433                                 options.escape_char = (u_char) optarg[0];
 434                         else if (strcmp(optarg, "none") == 0)
 435                                 options.escape_char = SSH_ESCAPECHAR_NONE;
 436                         else {
 437                                 fprintf(stderr, "Bad escape character '%s'.\n",
 438                                     optarg);
 439                                 exit(255);
 440                         }
 441                         break;
 442                 case 'c':
 443                         if (ciphers_valid(optarg)) {
 444                                 /* SSH2 only */
 445                                 options.ciphers = xstrdup(optarg);
 446                                 options.cipher = SSH_CIPHER_INVALID;
 447                         } else {
 448                                 /* SSH1 only */
 449                                 options.cipher = cipher_number(optarg);
 450                                 if (options.cipher == -1) {
 451                                         fprintf(stderr,
 452                                             "Unknown cipher type '%s'\n",
 453                                             optarg);
 454                                         exit(255);
 455                                 }
 456                                 if (options.cipher == SSH_CIPHER_3DES)
 457                                         options.ciphers = "3des-cbc";
 458                                 else if (options.cipher == SSH_CIPHER_BLOWFISH)
 459                                         options.ciphers = "blowfish-cbc";
 460                                 else
 461                                         options.ciphers = (char *)-1;
 462                         }
 463                         break;
 464                 case 'm':
 465                         if (mac_valid(optarg))
 466                                 options.macs = xstrdup(optarg);
 467                         else {
 468                                 fprintf(stderr, "Unknown mac type '%s'\n",
 469                                     optarg);
 470                                 exit(255);
 471                         }
 472                         break;
 473                 case 'M':
 474                         if (options.control_master == SSHCTL_MASTER_YES)
 475                                 options.control_master = SSHCTL_MASTER_ASK;
 476                         else
 477                                 options.control_master = SSHCTL_MASTER_YES;
 478                         break;
 479                 case 'p':
 480                         options.port = a2port(optarg);
 481                         if (options.port <= 0) {
 482                                 fprintf(stderr, "Bad port '%s'\n", optarg);
 483                                 exit(255);
 484                         }
 485                         break;
 486                 case 'l':
 487                         options.user = optarg;
 488                         break;
 489
 490                 case 'L':
 491                         if (parse_forward(&fwd, optarg, 0, 0))
 492                                 add_local_forward(&options, &fwd);
 493                         else {
 494                                 fprintf(stderr,
 495                                     "Bad local forwarding specification '%s'\n",
 496                                     optarg);
 497                                 exit(255);
 498                         }
 499                         break;
 500
 501                 case 'R':
 502                         if (parse_forward(&fwd, optarg, 0, 1)) {
 503                                 add_remote_forward(&options, &fwd);
 504                         } else {
 505                                 fprintf(stderr,
 506                                     "Bad remote forwarding specification "
 507                                     "'%s'\n", optarg);
 508                                 exit(255);
 509                         }
 510                         break;
 511
 512                 case 'D':
 513                         if (parse_forward(&fwd, optarg, 1, 0)) {
 514                                 add_local_forward(&options, &fwd);
 515                         } else {
 516                                 fprintf(stderr,
 517                                     "Bad dynamic forwarding specification "
 518                                     "'%s'\n", optarg);
 519                                 exit(255);
 520                         }
 521                         break;
 522
 523                 case 'C':
 524                         options.compression = 1;
 525                         break;
 526                 case 'N':
 527                         no_shell_flag = 1;
 528                         no_tty_flag = 1;
 529                         break;
 530                 case 'T':
 531                         no_tty_flag = 1;
 532                         break;
 533                 case 'o':
 534                         dummy = 1;
 535                         line = xstrdup(optarg);
 536                         if (process_config_line(&options, host ? host : "",
 537                             line, "command-line", 0, &dummy) != 0)
 538                                 exit(255);
 539                         xfree(line);
 540                         break;
 541                 case 's':
 542                         subsystem_flag = 1;
 543                         break;
 544                 case 'S':
 545                         if (options.control_path != NULL)
 546                                 free(options.control_path);
 547                         options.control_path = xstrdup(optarg);
 548                         break;
 549                 case 'b':
 550                         options.bind_address = optarg;
 551                         break;
 552                 case 'F':
 553                         config = optarg;
 554                         break;
 555                 default:
 556                         usage();
 557                 }
 558         }
 559
 560         ac -= optind;
 561         av += optind;
 562
 563         if (ac > 0 && !host) {
 564                 if (strrchr(*av, '@')) {
 565                         p = xstrdup(*av);
 566                         cp = strrchr(p, '@');
 567                         if (cp == NULL || cp == p)
 568                                 usage();
 569                         options.user = p;
 570                         *cp = '\0';
 571                         host = ++cp;
 572                 } else
 573                         host = *av;
 574                 if (ac > 1) {
 575                         optind = optreset = 1;
 576                         goto again;
 577                 }
 578                 ac--, av++;
 579         }
 580
 581         /* Check that we got a host name. */
 582         if (!host)
 583                 usage();
 584
 585         SSLeay_add_all_algorithms();
 586         ERR_load_crypto_strings();
 587
 588         /* Initialize the command to execute on remote host. */
 589         buffer_init(&command);
 590
 591         /*
 592          * Save the command to execute on the remote host in a buffer. There
 593          * is no limit on the length of the command, except by the maximum
 594          * packet size.  Also sets the tty flag if there is no command.
 595          */
 596         if (!ac) {
 597                 /* No command specified - execute shell on a tty. */
 598                 tty_flag = 1;
 599                 if (subsystem_flag) {
 600                         fprintf(stderr,
 601                             "You must specify a subsystem to invoke.\n");
 602                         usage();
 603                 }
 604         } else {
 605                 /* A command has been specified.  Store it into the buffer. */
 606                 for (i = 0; i < ac; i++) {
 607                         if (i)
 608                                 buffer_append(&command, " ", 1);
 609                         buffer_append(&command, av[i], strlen(av[i]));
 610                 }
 611         }
 612
 613         /* Cannot fork to background if no command. */
 614         if (fork_after_authentication_flag && buffer_len(&command) == 0 &&
 615             !no_shell_flag)
 616                 fatal("Cannot fork into background without a command "
 617                     "to execute.");
 618
 619         /* Allocate a tty by default if no command specified. */
 620         if (buffer_len(&command) == 0)
 621                 tty_flag = 1;
 622
 623         /* Force no tty */
 624         if (no_tty_flag)
 625                 tty_flag = 0;
 626         /* Do not allocate a tty if stdin is not a tty. */
 627         if ((!isatty(fileno(stdin)) || stdin_null_flag) && !force_tty_flag) {
 628                 if (tty_flag)
 629                         logit("Pseudo-terminal will not be allocated because "
 630                             "stdin is not a terminal.");
 631                 tty_flag = 0;
 632         }
 633
 634         /*
 635          * Initialize "log" output.  Since we are the client all output
 636          * actually goes to stderr.
 637          */
 638         log_init(argv0,
 639             options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level,
 640             SYSLOG_FACILITY_USER, !use_syslog);
 641
 642         /*
 643          * Read per-user configuration file.  Ignore the system wide config
 644          * file if the user specifies a config file on the command line.
 645          */
 646         if (config != NULL) {
 647                 if (!read_config_file(config, host, &options, 0))
 648                         fatal("Can't open user config file %.100s: "
 649                             "%.100s", config, strerror(errno));
 650         } else {
 651                 r = snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir,
 652                     _PATH_SSH_USER_CONFFILE);
 653                 if (r > 0 && (size_t)r < sizeof(buf))
 654                         (void)read_config_file(buf, host, &options, 1);
 655
 656                 /* Read systemwide configuration file after use config. */
 657                 (void)read_config_file(_PATH_HOST_CONFIG_FILE, host,
 658                     &options, 0);
 659         }
 660
 661         /* Fill configuration defaults. */
 662         fill_default_options(&options);
 663
 664         channel_set_af(options.address_family);
 665
 666         /* reinit */
 667         log_init(argv0, options.log_level, SYSLOG_FACILITY_USER, !use_syslog);
 668
 669         seed_rng();
 670
 671         if (options.user == NULL)
 672                 options.user = xstrdup(pw->pw_name);
 673
 674         /* Get default port if port has not been set. */
 675         if (options.port == 0) {
 676                 sp = getservbyname(SSH_SERVICE_NAME, "tcp");
 677                 options.port = sp ? ntohs(sp->s_port) : SSH_DEFAULT_PORT;
 678         }
 679
 680         if (options.local_command != NULL) {
 681                 char thishost[NI_MAXHOST];
 682
 683                 if (gethostname(thishost, sizeof(thishost)) == -1)
 684                         fatal("gethostname: %s", strerror(errno));
 685                 snprintf(buf, sizeof(buf), "%d", options.port);
 686                 debug3("expanding LocalCommand: %s", options.local_command);
 687                 cp = options.local_command;
 688                 options.local_command = percent_expand(cp, "d", pw->pw_dir,
 689                     "h", options.hostname? options.hostname : host,
 690                     "l", thishost, "n", host, "r", options.user, "p", buf,
 691                     "u", pw->pw_name, (char *)NULL);
 692                 debug3("expanded LocalCommand: %s", options.local_command);
 693                 xfree(cp);
 694         }
 695
 696         if (options.hostname != NULL)
 697                 host = options.hostname;
 698
 699         /* Find canonic host name. */
 700         if (strchr(host, '.') == 0) {
 701                 struct addrinfo hints;
 702                 struct addrinfo *ai = NULL;
 703                 int errgai;
 704                 memset(&hints, 0, sizeof(hints));
 705                 hints.ai_family = options.address_family;
 706                 hints.ai_flags = AI_CANONNAME;
 707                 hints.ai_socktype = SOCK_STREAM;
 708                 errgai = getaddrinfo(host, NULL, &hints, &ai);
 709                 if (errgai == 0) {
 710                         if (ai->ai_canonname != NULL)
 711                                 host = xstrdup(ai->ai_canonname);
 712                         freeaddrinfo(ai);
 713                 }
 714         }
 715
 716         /* force lowercase for hostkey matching */
 717         if (options.host_key_alias != NULL) {
 718                 for (p = options.host_key_alias; *p; p++)
 719                         if (isupper(*p))
 720                                 *p = (char)tolower(*p);
 721         }
 722
 723         if (options.proxy_command != NULL &&
 724             strcmp(options.proxy_command, "none") == 0) {
 725                 xfree(options.proxy_command);
 726                 options.proxy_command = NULL;
 727         }
 728         if (options.control_path != NULL &&
 729             strcmp(options.control_path, "none") == 0) {
 730                 xfree(options.control_path);
 731                 options.control_path = NULL;
 732         }
 733
 734         if (options.control_path != NULL) {
 735                 char thishost[NI_MAXHOST];
 736
 737                 if (gethostname(thishost, sizeof(thishost)) == -1)
 738                         fatal("gethostname: %s", strerror(errno));
 739                 snprintf(buf, sizeof(buf), "%d", options.port);
 740                 cp = tilde_expand_filename(options.control_path,
 741                     original_real_uid);
 742                 xfree(options.control_path);
 743                 options.control_path = percent_expand(cp, "p", buf, "h", host,
 744                     "r", options.user, "l", thishost, (char *)NULL);
 745                 xfree(cp);
 746         }
 747         if (muxclient_command != 0 && options.control_path == NULL)
 748                 fatal("No ControlPath specified for \"-O\" command");
 749         if (options.control_path != NULL)
 750                 muxclient(options.control_path);
 751
 752         timeout_ms = options.connection_timeout * 1000;
 753
 754         /* Open a connection to the remote host. */
 755         if (ssh_connect(host, &hostaddr, options.port,
 756             options.address_family, options.connection_attempts, &timeout_ms,
 757             options.tcp_keep_alive,
 758 #ifdef HAVE_CYGWIN
 759             options.use_privileged_port,
 760 #else
 761             original_effective_uid == 0 && options.use_privileged_port,
 762 #endif
 763             options.proxy_command) != 0)
 764                 exit(255);
 765
 766         if (timeout_ms > 0)
 767                 debug3("timeout: %d ms remain after connect", timeout_ms);
 768
 769         /*
 770          * If we successfully made the connection, load the host private key
 771          * in case we will need it later for combined rsa-rhosts
 772          * authentication. This must be done before releasing extra
 773          * privileges, because the file is only readable by root.
 774          * If we cannot access the private keys, load the public keys
 775          * instead and try to execute the ssh-keysign helper instead.
 776          */
 777         sensitive_data.nkeys = 0;
 778         sensitive_data.keys = NULL;
 779         sensitive_data.external_keysign = 0;
 780         if (options.rhosts_rsa_authentication ||
 781             options.hostbased_authentication) {
 782                 sensitive_data.nkeys = 3;
 783                 sensitive_data.keys = xcalloc(sensitive_data.nkeys,
 784                     sizeof(Key));
 785
 786                 PRIV_START;
 787                 sensitive_data.keys[0] = key_load_private_type(KEY_RSA1,
 788                     _PATH_HOST_KEY_FILE, "", NULL, NULL);
 789                 sensitive_data.keys[1] = key_load_private_type(KEY_DSA,
 790                     _PATH_HOST_DSA_KEY_FILE, "", NULL, NULL);
 791                 sensitive_data.keys[2] = key_load_private_type(KEY_RSA,
 792                     _PATH_HOST_RSA_KEY_FILE, "", NULL, NULL);
 793                 PRIV_END;
 794
 795                 if (options.hostbased_authentication == 1 &&
 796                     sensitive_data.keys[0] == NULL &&
 797                     sensitive_data.keys[1] == NULL &&
 798                     sensitive_data.keys[2] == NULL) {
 799                         sensitive_data.keys[1] = key_load_public(
 800                             _PATH_HOST_DSA_KEY_FILE, NULL);
 801                         sensitive_data.keys[2] = key_load_public(
 802                             _PATH_HOST_RSA_KEY_FILE, NULL);
 803                         sensitive_data.external_keysign = 1;
 804                 }
 805         }
 806         /*
 807          * Get rid of any extra privileges that we may have.  We will no
 808          * longer need them.  Also, extra privileges could make it very hard
 809          * to read identity files and other non-world-readable files from the
 810          * user's home directory if it happens to be on a NFS volume where
 811          * root is mapped to nobody.
 812          */
 813         if (original_effective_uid == 0) {
 814                 PRIV_START;
 815                 permanently_set_uid(pw);
 816         }
 817
 818         /*
 819          * Now that we are back to our own permissions, create ~/.ssh
 820          * directory if it doesn't already exist.
 821          */
 822         r = snprintf(buf, sizeof buf, "%s%s%s", pw->pw_dir,
 823             strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR);
 824         if (r > 0 && (size_t)r < sizeof(buf) && stat(buf, &st) < 0)
 825                 if (mkdir(buf, 0700) < 0)
 826                         error("Could not create directory '%.200s'.", buf);
 827
 828         /* load options.identity_files */
 829         load_public_identity_files();
 830
 831         /* Expand ~ in known host file names. */
 832         /* XXX mem-leaks: */
 833         options.system_hostfile =
 834             tilde_expand_filename(options.system_hostfile, original_real_uid);
 835         options.user_hostfile =
 836             tilde_expand_filename(options.user_hostfile, original_real_uid);
 837         options.system_hostfile2 =
 838             tilde_expand_filename(options.system_hostfile2, original_real_uid);
 839         options.user_hostfile2 =
 840             tilde_expand_filename(options.user_hostfile2, original_real_uid);
 841
 842         signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */
 843
 844         /* Log into the remote system.  Never returns if the login fails. */
 845         ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr,
 846             pw, timeout_ms);
 847
 848         /* We no longer need the private host keys.  Clear them now. */
 849         if (sensitive_data.nkeys != 0) {
 850                 for (i = 0; i < sensitive_data.nkeys; i++) {
 851                         if (sensitive_data.keys[i] != NULL) {
 852                                 /* Destroys contents safely */
 853                                 debug3("clear hostkey %d", i);
 854                                 key_free(sensitive_data.keys[i]);
 855                                 sensitive_data.keys[i] = NULL;
 856                         }
 857                 }
 858                 xfree(sensitive_data.keys);
 859         }
 860         for (i = 0; i < options.num_identity_files; i++) {
 861                 if (options.identity_files[i]) {
 862                         xfree(options.identity_files[i]);
 863                         options.identity_files[i] = NULL;
 864                 }
 865                 if (options.identity_keys[i]) {
 866                         key_free(options.identity_keys[i]);
 867                         options.identity_keys[i] = NULL;
 868                 }
 869         }
 870
 871         exit_status = compat20 ? ssh_session2() : ssh_session();
 872         packet_close();
 873
 874         if (options.control_path != NULL && muxserver_sock != -1)
 875                 unlink(options.control_path);
 876
 877         /*
 878          * Send SIGHUP to proxy command if used. We don't wait() in
 879          * case it hangs and instead rely on init to reap the child
 880          */
 881         if (proxy_command_pid > 1)
 882                 kill(proxy_command_pid, SIGHUP);
 883
 884         return exit_status;
 885 }
 886
 887 /* Callback for remote forward global requests */
 888 static void
 889 ssh_confirm_remote_forward(int type, u_int32_t seq, void *ctxt)
 890 {
 891         Forward *rfwd = (Forward *)ctxt;
 892
 893         /* XXX verbose() on failure? */
 894         debug("remote forward %s for: listen %d, connect %s:%d",
 895             type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure",
 896             rfwd->listen_port, rfwd->connect_host, rfwd->connect_port);
 897         if (type == SSH2_MSG_REQUEST_SUCCESS && rfwd->listen_port == 0) {
 898                 logit("Allocated port %u for remote forward to %s:%d",
 899                         packet_get_int(),
 900                         rfwd->connect_host, rfwd->connect_port);
 901         }
 902
 903         if (type == SSH2_MSG_REQUEST_FAILURE) {
 904                 if (options.exit_on_forward_failure)
 905                         fatal("Error: remote port forwarding failed for "
 906                             "listen port %d", rfwd->listen_port);
 907                 else
 908                         logit("Warning: remote port forwarding failed for "
 909                             "listen port %d", rfwd->listen_port);
 910         }
 911         if (++remote_forward_confirms_received == options.num_remote_forwards) {
 912                 debug("All remote forwarding requests processed");
 913                 if (fork_after_authentication_flag) {
 914                         fork_after_authentication_flag = 0;
 915                         if (daemon(1, 1) < 0)
 916                                 fatal("daemon() failed: %.200s",
 917                                     strerror(errno));
 918                 }
 919         }
 920 }
 921
 922 static void
 923 client_cleanup_stdio_fwd(int id, void *arg)
 924 {
 925         debug("stdio forwarding: done");
 926         cleanup_exit(0);
 927 }
 928
 929 static int
 930 client_setup_stdio_fwd(const char *host_to_connect, u_short port_to_connect)
 931 {
 932         Channel *c;
 933         int in, out;
 934
 935         debug3("client_setup_stdio_fwd %s:%d", host_to_connect,
 936             port_to_connect);
 937
 938         in = dup(STDIN_FILENO);
 939         out = dup(STDOUT_FILENO);
 940         if (in < 0 || out < 0)
 941                 fatal("channel_connect_stdio_fwd: dup() in/out failed");
 942
 943         if ((c = channel_connect_stdio_fwd(host_to_connect, port_to_connect,
 944             in, out)) == NULL)
 945                 return 0;
 946         channel_register_cleanup(c->self, client_cleanup_stdio_fwd, 0);
 947         return 1;
 948 }
 949
 950 static void
 951 ssh_init_forwarding(void)
 952 {
 953         int success = 0;
 954         int i;
 955
 956         if (stdio_forward_host != NULL) {
 957                 if (!compat20) {
 958                         fatal("stdio forwarding require Protocol 2");
 959                 }
 960                 if (!client_setup_stdio_fwd(stdio_forward_host,
 961                     stdio_forward_port))
 962                         fatal("Failed to connect in stdio forward mode.");
 963         }
 964
 965         /* Initiate local TCP/IP port forwardings. */
 966         for (i = 0; i < options.num_local_forwards; i++) {
 967                 debug("Local connections to %.200s:%d forwarded to remote "
 968                     "address %.200s:%d",
 969                     (options.local_forwards[i].listen_host == NULL) ?
 970                     (options.gateway_ports ? "*" : "LOCALHOST") :
 971                     options.local_forwards[i].listen_host,
 972                     options.local_forwards[i].listen_port,
 973                     options.local_forwards[i].connect_host,
 974                     options.local_forwards[i].connect_port);
 975                 success += channel_setup_local_fwd_listener(
 976                     options.local_forwards[i].listen_host,
 977                     options.local_forwards[i].listen_port,
 978                     options.local_forwards[i].connect_host,
 979                     options.local_forwards[i].connect_port,
 980                     options.gateway_ports);
 981         }
 982         if (i > 0 && success != i && options.exit_on_forward_failure)
 983                 fatal("Could not request local forwarding.");
 984         if (i > 0 && success == 0)
 985                 error("Could not request local forwarding.");
 986
 987         /* Initiate remote TCP/IP port forwardings. */
 988         for (i = 0; i < options.num_remote_forwards; i++) {
 989                 debug("Remote connections from %.200s:%d forwarded to "
 990                     "local address %.200s:%d",
 991                     (options.remote_forwards[i].listen_host == NULL) ?
 992                     "LOCALHOST" : options.remote_forwards[i].listen_host,
 993                     options.remote_forwards[i].listen_port,
 994                     options.remote_forwards[i].connect_host,
 995                     options.remote_forwards[i].connect_port);
 996                 if (channel_request_remote_forwarding(
 997                     options.remote_forwards[i].listen_host,
 998                     options.remote_forwards[i].listen_port,
 999                     options.remote_forwards[i].connect_host,
1000                     options.remote_forwards[i].connect_port) < 0) {
1001                         if (options.exit_on_forward_failure)
1002                                 fatal("Could not request remote forwarding.");
1003                         else
1004                                 logit("Warning: Could not request remote "
1005                                     "forwarding.");
1006                 }
1007                 client_register_global_confirm(ssh_confirm_remote_forward,
1008                     &options.remote_forwards[i]);
1009         }
1010
1011         /* Initiate tunnel forwarding. */
1012         if (options.tun_open != SSH_TUNMODE_NO) {
1013                 if (client_request_tun_fwd(options.tun_open,
1014                     options.tun_local, options.tun_remote) == -1) {
1015                         if (options.exit_on_forward_failure)
1016                                 fatal("Could not request tunnel forwarding.");
1017                         else
1018                                 error("Could not request tunnel forwarding.");
1019                 }
1020         }
1021 }
1022
1023 static void
1024 check_agent_present(void)
1025 {
1026         if (options.forward_agent) {
1027                 /* Clear agent forwarding if we don't have an agent. */
1028                 if (!ssh_agent_present())
1029                         options.forward_agent = 0;
1030         }
1031 }
1032
1033 static int
1034 ssh_session(void)
1035 {
1036         int type;
1037         int interactive = 0;
1038         int have_tty = 0;
1039         struct winsize ws;
1040         char *cp;
1041         const char *display;
1042
1043         /* Enable compression if requested. */
1044         if (options.compression) {
1045                 debug("Requesting compression at level %d.",
1046                     options.compression_level);
1047
1048                 if (options.compression_level < 1 ||
1049                     options.compression_level > 9)
1050                         fatal("Compression level must be from 1 (fast) to "
1051                             "9 (slow, best).");
1052
1053                 /* Send the request. */
1054                 packet_start(SSH_CMSG_REQUEST_COMPRESSION);
1055                 packet_put_int(options.compression_level);
1056                 packet_send();
1057                 packet_write_wait();
1058                 type = packet_read();
1059                 if (type == SSH_SMSG_SUCCESS)
1060                         packet_start_compression(options.compression_level);
1061                 else if (type == SSH_SMSG_FAILURE)
1062                         logit("Warning: Remote host refused compression.");
1063                 else
1064                         packet_disconnect("Protocol error waiting for "
1065                             "compression response.");
1066         }
1067         /* Allocate a pseudo tty if appropriate. */
1068         if (tty_flag) {
1069                 debug("Requesting pty.");
1070
1071                 /* Start the packet. */
1072                 packet_start(SSH_CMSG_REQUEST_PTY);
1073
1074                 /* Store TERM in the packet.  There is no limit on the
1075                    length of the string. */
1076                 cp = getenv("TERM");
1077                 if (!cp)
1078                         cp = "";
1079                 packet_put_cstring(cp);
1080
1081                 /* Store window size in the packet. */
1082                 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
1083                         memset(&ws, 0, sizeof(ws));
1084                 packet_put_int((u_int)ws.ws_row);
1085                 packet_put_int((u_int)ws.ws_col);
1086                 packet_put_int((u_int)ws.ws_xpixel);
1087                 packet_put_int((u_int)ws.ws_ypixel);
1088
1089                 /* Store tty modes in the packet. */
1090                 tty_make_modes(fileno(stdin), NULL);
1091
1092                 /* Send the packet, and wait for it to leave. */
1093                 packet_send();
1094                 packet_write_wait();
1095
1096                 /* Read response from the server. */
1097                 type = packet_read();
1098                 if (type == SSH_SMSG_SUCCESS) {
1099                         interactive = 1;
1100                         have_tty = 1;
1101                 } else if (type == SSH_SMSG_FAILURE)
1102                         logit("Warning: Remote host failed or refused to "
1103                             "allocate a pseudo tty.");
1104                 else
1105                         packet_disconnect("Protocol error waiting for pty "
1106                             "request response.");
1107         }
1108         /* Request X11 forwarding if enabled and DISPLAY is set. */
1109         display = getenv("DISPLAY");
1110         if (options.forward_x11 && display != NULL) {
1111                 char *proto, *data;
1112                 /* Get reasonable local authentication information. */
1113                 client_x11_get_proto(display, options.xauth_location,
1114                     options.forward_x11_trusted, &proto, &data);
1115                 /* Request forwarding with authentication spoofing. */
1116                 debug("Requesting X11 forwarding with authentication "
1117                     "spoofing.");
1118                 x11_request_forwarding_with_spoofing(0, display, proto, data);
1119
1120                 /* Read response from the server. */
1121                 type = packet_read();
1122                 if (type == SSH_SMSG_SUCCESS) {
1123                         interactive = 1;
1124                 } else if (type == SSH_SMSG_FAILURE) {
1125                         logit("Warning: Remote host denied X11 forwarding.");
1126                 } else {
1127                         packet_disconnect("Protocol error waiting for X11 "
1128                             "forwarding");
1129                 }
1130         }
1131         /* Tell the packet module whether this is an interactive session. */
1132         packet_set_interactive(interactive);
1133
1134         /* Request authentication agent forwarding if appropriate. */
1135         check_agent_present();
1136
1137         if (options.forward_agent) {
1138                 debug("Requesting authentication agent forwarding.");
1139                 auth_request_forwarding();
1140
1141                 /* Read response from the server. */
1142                 type = packet_read();
1143                 packet_check_eom();
1144                 if (type != SSH_SMSG_SUCCESS)
1145                         logit("Warning: Remote host denied authentication agent forwarding.");
1146         }
1147
1148         /* Initiate port forwardings. */
1149         ssh_init_forwarding();
1150
1151         /* Execute a local command */
1152         if (options.local_command != NULL &&
1153             options.permit_local_command)
1154                 ssh_local_cmd(options.local_command);
1155
1156         /*
1157          * If requested and we are not interested in replies to remote
1158          * forwarding requests, then let ssh continue in the background.
1159          */
1160         if (fork_after_authentication_flag &&
1161             (!options.exit_on_forward_failure ||
1162             options.num_remote_forwards == 0)) {
1163                 fork_after_authentication_flag = 0;
1164                 if (daemon(1, 1) < 0)
1165                         fatal("daemon() failed: %.200s", strerror(errno));
1166         }
1167
1168         /*
1169          * If a command was specified on the command line, execute the
1170          * command now. Otherwise request the server to start a shell.
1171          */
1172         if (buffer_len(&command) > 0) {
1173                 int len = buffer_len(&command);
1174                 if (len > 900)
1175                         len = 900;
1176                 debug("Sending command: %.*s", len,
1177                     (u_char *)buffer_ptr(&command));
1178                 packet_start(SSH_CMSG_EXEC_CMD);
1179                 packet_put_string(buffer_ptr(&command), buffer_len(&command));
1180                 packet_send();
1181                 packet_write_wait();
1182         } else {
1183                 debug("Requesting shell.");
1184                 packet_start(SSH_CMSG_EXEC_SHELL);
1185                 packet_send();
1186                 packet_write_wait();
1187         }
1188
1189         /* Enter the interactive session. */
1190         return client_loop(have_tty, tty_flag ?
1191             options.escape_char : SSH_ESCAPECHAR_NONE, 0);
1192 }
1193
1194 /* request pty/x11/agent/tcpfwd/shell for channel */
1195 static void
1196 ssh_session2_setup(int id, void *arg)
1197 {
1198         extern char **environ;
1199         const char *display;
1200         int interactive = tty_flag;
1201
1202         display = getenv("DISPLAY");
1203         if (options.forward_x11 && display != NULL) {
1204                 char *proto, *data;
1205                 /* Get reasonable local authentication information. */
1206                 client_x11_get_proto(display, options.xauth_location,
1207                     options.forward_x11_trusted, &proto, &data);
1208                 /* Request forwarding with authentication spoofing. */
1209                 debug("Requesting X11 forwarding with authentication "
1210                     "spoofing.");
1211                 x11_request_forwarding_with_spoofing(id, display, proto, data);
1212                 interactive = 1;
1213                 /* XXX wait for reply */
1214         }
1215
1216         check_agent_present();
1217         if (options.forward_agent) {
1218                 debug("Requesting authentication agent forwarding.");
1219                 channel_request_start(id, "auth-agent-req@openssh.com", 0);
1220                 packet_send();
1221         }
1222
1223         client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"),
1224             NULL, fileno(stdin), &command, environ);
1225
1226         packet_set_interactive(interactive);
1227 }
1228
1229 /* open new channel for a session */
1230 static int
1231 ssh_session2_open(void)
1232 {
1233         Channel *c;
1234         int window, packetmax, in, out, err;
1235
1236         if (stdin_null_flag) {
1237                 in = open(_PATH_DEVNULL, O_RDONLY);
1238         } else {
1239                 in = dup(STDIN_FILENO);
1240         }
1241         out = dup(STDOUT_FILENO);
1242         err = dup(STDERR_FILENO);
1243
1244         if (in < 0 || out < 0 || err < 0)
1245                 fatal("dup() in/out/err failed");
1246
1247         /* enable nonblocking unless tty */
1248         if (!isatty(in))
1249                 set_nonblock(in);
1250         if (!isatty(out))
1251                 set_nonblock(out);
1252         if (!isatty(err))
1253                 set_nonblock(err);
1254
1255         window = CHAN_SES_WINDOW_DEFAULT;
1256         packetmax = CHAN_SES_PACKET_DEFAULT;
1257         if (tty_flag) {
1258                 window >>= 1;
1259                 packetmax >>= 1;
1260         }
1261         c = channel_new(
1262             "session", SSH_CHANNEL_OPENING, in, out, err,
1263             window, packetmax, CHAN_EXTENDED_WRITE,
1264             "client-session", /*nonblock*/0);
1265
1266         debug3("ssh_session2_open: channel_new: %d", c->self);
1267
1268         channel_send_open(c->self);
1269         if (!no_shell_flag)
1270                 channel_register_open_confirm(c->self,
1271                     ssh_session2_setup, NULL);
1272
1273         return c->self;
1274 }
1275
1276 static int
1277 ssh_session2(void)
1278 {
1279         int id = -1;
1280
1281         /* XXX should be pre-session */
1282         ssh_init_forwarding();
1283
1284         if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN))
1285                 id = ssh_session2_open();
1286
1287         /* If we don't expect to open a new session, then disallow it */
1288         if (options.control_master == SSHCTL_MASTER_NO &&
1289             (datafellows & SSH_NEW_OPENSSH)) {
1290                 debug("Requesting no-more-sessions@openssh.com");
1291                 packet_start(SSH2_MSG_GLOBAL_REQUEST);
1292                 packet_put_cstring("no-more-sessions@openssh.com");
1293                 packet_put_char(0);
1294                 packet_send();
1295         }
1296
1297         /* Execute a local command */
1298         if (options.local_command != NULL &&
1299             options.permit_local_command)
1300                 ssh_local_cmd(options.local_command);
1301
1302         /* Start listening for multiplex clients */
1303         muxserver_listen();
1304
1305         /* If requested, let ssh continue in the background. */
1306         if (fork_after_authentication_flag) {
1307                 fork_after_authentication_flag = 0;
1308                 if (daemon(1, 1) < 0)
1309                         fatal("daemon() failed: %.200s", strerror(errno));
1310         }
1311
1312         if (options.use_roaming)
1313                 request_roaming();
1314
1315         return client_loop(tty_flag, tty_flag ?
1316             options.escape_char : SSH_ESCAPECHAR_NONE, id);
1317 }
1318
1319 static void
1320 load_public_identity_files(void)
1321 {
1322         char *filename, *cp, thishost[NI_MAXHOST];
1323         char *pwdir = NULL, *pwname = NULL;
1324         int i = 0;
1325         Key *public;
1326         struct passwd *pw;
1327         u_int n_ids;
1328         char *identity_files[SSH_MAX_IDENTITY_FILES];
1329         Key *identity_keys[SSH_MAX_IDENTITY_FILES];
1330 #ifdef ENABLE_PKCS11
1331         Key **keys;
1332         int nkeys;
1333 #endif /* PKCS11 */
1334
1335         n_ids = 0;
1336         bzero(identity_files, sizeof(identity_files));
1337         bzero(identity_keys, sizeof(identity_keys));
1338
1339 #ifdef ENABLE_PKCS11
1340         if (options.pkcs11_provider != NULL &&
1341             options.num_identity_files < SSH_MAX_IDENTITY_FILES &&
1342             (pkcs11_init(!options.batch_mode) == 0) &&
1343             (nkeys = pkcs11_add_provider(options.pkcs11_provider, NULL,
1344             &keys)) > 0) {
1345                 for (i = 0; i < nkeys; i++) {
1346                         if (n_ids >= SSH_MAX_IDENTITY_FILES) {
1347                                 key_free(keys[i]);
1348                                 continue;
1349                         }
1350                         identity_keys[n_ids] = keys[i];
1351                         identity_files[n_ids] =
1352                             xstrdup(options.pkcs11_provider); /* XXX */
1353                         n_ids++;
1354                 }
1355                 xfree(keys);
1356         }
1357 #endif /* ENABLE_PKCS11 */
1358         if ((pw = getpwuid(original_real_uid)) == NULL)
1359                 fatal("load_public_identity_files: getpwuid failed");
1360         pwname = xstrdup(pw->pw_name);
1361         pwdir = xstrdup(pw->pw_dir);
1362         if (gethostname(thishost, sizeof(thishost)) == -1)
1363                 fatal("load_public_identity_files: gethostname: %s",
1364                     strerror(errno));
1365         for (i = 0; i < options.num_identity_files; i++) {
1366                 if (n_ids >= SSH_MAX_IDENTITY_FILES) {
1367                         xfree(options.identity_files[i]);
1368                         continue;
1369                 }
1370                 cp = tilde_expand_filename(options.identity_files[i],
1371                     original_real_uid);
1372                 filename = percent_expand(cp, "d", pwdir,
1373                     "u", pwname, "l", thishost, "h", host,
1374                     "r", options.user, (char *)NULL);
1375                 xfree(cp);
1376                 public = key_load_public(filename, NULL);
1377                 debug("identity file %s type %d", filename,
1378                     public ? public->type : -1);
1379                 xfree(options.identity_files[i]);
1380                 identity_files[n_ids] = filename;
1381                 identity_keys[n_ids] = public;
1382
1383                 if (++n_ids >= SSH_MAX_IDENTITY_FILES)
1384                         continue;
1385
1386                 /* Try to add the certificate variant too */
1387                 xasprintf(&cp, "%s-cert", filename);
1388                 public = key_load_public(cp, NULL);
1389                 debug("identity file %s type %d", cp,
1390                     public ? public->type : -1);
1391                 if (public == NULL) {
1392                         xfree(cp);
1393                         continue;
1394                 }
1395                 if (!key_is_cert(public)) {
1396                         debug("%s: key %s type %s is not a certificate",
1397                             __func__, cp, key_type(public));
1398                         key_free(public);
1399                         xfree(cp);
1400                         continue;
1401                 }
1402                 identity_keys[n_ids] = public;
1403                 /* point to the original path, most likely the private key */
1404                 identity_files[n_ids] = xstrdup(filename);
1405                 n_ids++;
1406         }
1407         options.num_identity_files = n_ids;
1408         memcpy(options.identity_files, identity_files, sizeof(identity_files));
1409         memcpy(options.identity_keys, identity_keys, sizeof(identity_keys));
1410
1411         bzero(pwname, strlen(pwname));
1412         xfree(pwname);
1413         bzero(pwdir, strlen(pwdir));
1414         xfree(pwdir);
1415 }