session.c

   1 /*
   2  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
   3  *                    All rights reserved
   4  *
   5  * As far as I am concerned, the code I have written for this software
   6  * can be used freely for any purpose.  Any derived versions of this
   7  * software must be clearly marked as such, and if the derived work is
   8  * incompatible with the protocol description in the RFC file, it must be
   9  * called by a name other than "ssh" or "Secure Shell".
  10  *
  11  * SSH2 support by Markus Friedl.
  12  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  13  *
  14  * Redistribution and use in source and binary forms, with or without
  15  * modification, are permitted provided that the following conditions
  16  * are met:
  17  * 1. Redistributions of source code must retain the above copyright
  18  *    notice, this list of conditions and the following disclaimer.
  19  * 2. Redistributions in binary form must reproduce the above copyright
  20  *    notice, this list of conditions and the following disclaimer in the
  21  *    documentation and/or other materials provided with the distribution.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  26  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  33  */
  34
  35 #include "includes.h"
  36 RCSID("$OpenBSD: session.c,v 1.71 2001/04/06 21:00:12 markus Exp $");
  37
  38 #include "ssh.h"
  39 #include "ssh1.h"
  40 #include "ssh2.h"
  41 #include "xmalloc.h"
  42 #include "sshpty.h"
  43 #include "packet.h"
  44 #include "buffer.h"
  45 #include "mpaux.h"
  46 #include "uidswap.h"
  47 #include "compat.h"
  48 #include "channels.h"
  49 #include "nchan.h"
  50 #include "bufaux.h"
  51 #include "auth.h"
  52 #include "auth-options.h"
  53 #include "pathnames.h"
  54 #include "log.h"
  55 #include "servconf.h"
  56 #include "sshlogin.h"
  57 #include "serverloop.h"
  58 #include "canohost.h"
  59 #include "session.h"
  60
  61 #ifdef WITH_IRIX_PROJECT
  62 #include <proj.h>
  63 #endif /* WITH_IRIX_PROJECT */
  64 #ifdef WITH_IRIX_JOBS
  65 #include <sys/resource.h>
  66 #endif
  67 #ifdef WITH_IRIX_AUDIT
  68 #include <sat.h>
  69 #endif /* WITH_IRIX_AUDIT */
  70
  71 #if defined(HAVE_USERSEC_H)
  72 #include <usersec.h>
  73 #endif
  74
  75 #ifdef HAVE_CYGWIN
  76 #include <windows.h>
  77 #include <sys/cygwin.h>
  78 #define is_winnt       (GetVersion() < 0x80000000)
  79 #endif
  80
  81 /* AIX limits */
  82 #if defined(HAVE_GETUSERATTR) && !defined(S_UFSIZE_HARD) && defined(S_UFSIZE)
  83 # define S_UFSIZE_HARD  S_UFSIZE "_hard"
  84 # define S_UCPU_HARD  S_UCPU "_hard"
  85 # define S_UDATA_HARD  S_UDATA "_hard"
  86 # define S_USTACK_HARD  S_USTACK "_hard"
  87 # define S_URSS_HARD  S_URSS "_hard"
  88 # define S_UCORE_HARD  S_UCORE "_hard"
  89 # define S_UNOFILE_HARD S_UNOFILE "_hard"
  90 #endif
  91
  92 #ifdef _AIX
  93 # include <uinfo.h>
  94 #endif
  95
  96 /* types */
  97
  98 #define TTYSZ 64
  99 typedef struct Session Session;
 100 struct Session {
 101         int     used;
 102         int     self;
 103         struct  passwd *pw;
 104         pid_t   pid;
 105         /* tty */
 106         char    *term;
 107         int     ptyfd, ttyfd, ptymaster;
 108         int     row, col, xpixel, ypixel;
 109         char    tty[TTYSZ];
 110         /* X11 */
 111         char    *display;
 112         int     screen;
 113         char    *auth_proto;
 114         char    *auth_data;
 115         int     single_connection;
 116         /* proto 2 */
 117         int     chanid;
 118         int     is_subsystem;
 119 };
 120
 121 /* func */
 122
 123 Session *session_new(void);
 124 void    session_set_fds(Session *s, int fdin, int fdout, int fderr);
 125 void    session_pty_cleanup(Session *s);
 126 void    session_proctitle(Session *s);
 127 void    do_exec_pty(Session *s, const char *command);
 128 void    do_exec_no_pty(Session *s, const char *command);
 129 void    do_login(Session *s, const char *command);
 130 void    do_child(Session *s, const char *command);
 131
 132 void    do_authenticated1(Authctxt *authctxt);
 133 void    do_authenticated2(Authctxt *authctxt);
 134
 135 /* import */
 136 extern ServerOptions options;
 137 extern char *__progname;
 138 extern int log_stderr;
 139 extern int debug_flag;
 140 extern u_int utmp_len;
 141
 142 extern int startup_pipe;
 143
 144 /* Local Xauthority file. */
 145 static char *xauthfile;
 146
 147 /* original command from peer. */
 148 char *original_command = NULL;
 149
 150 /* data */
 151 #define MAX_SESSIONS 10
 152 Session sessions[MAX_SESSIONS];
 153
 154 #ifdef WITH_AIXAUTHENTICATE
 155 /* AIX's lastlogin message, set in auth1.c */
 156 char *aixloginmsg;
 157 #endif /* WITH_AIXAUTHENTICATE */
 158
 159 #ifdef HAVE_LOGIN_CAP
 160 static login_cap_t *lc;
 161 #endif
 162
 163 void
 164 do_authenticated(Authctxt *authctxt)
 165 {
 166         /*
 167          * Cancel the alarm we set to limit the time taken for
 168          * authentication.
 169          */
 170         alarm(0);
 171         if (startup_pipe != -1) {
 172                 close(startup_pipe);
 173                 startup_pipe = -1;
 174         }
 175 #if defined(HAVE_LOGIN_CAP) && defined(HAVE_PW_CLASS_IN_PASSWD)
 176         if ((lc = login_getclass(authctxt->pw->pw_class)) == NULL) {
 177                 error("unable to get login class");
 178                 return;
 179         }
 180 #endif
 181         /* setup the channel layer */
 182         if (!no_port_forwarding_flag && options.allow_tcp_forwarding)
 183                 channel_permit_all_opens();
 184
 185         if (compat20)
 186                 do_authenticated2(authctxt);
 187         else
 188                 do_authenticated1(authctxt);
 189 }
 190
 191 /*
 192  * Remove local Xauthority file.
 193  */
 194 void
 195 xauthfile_cleanup_proc(void *ignore)
 196 {
 197         debug("xauthfile_cleanup_proc called");
 198
 199         if (xauthfile != NULL) {
 200                 char *p;
 201                 unlink(xauthfile);
 202                 p = strrchr(xauthfile, '/');
 203                 if (p != NULL) {
 204                         *p = '\0';
 205                         rmdir(xauthfile);
 206                 }
 207                 xfree(xauthfile);
 208                 xauthfile = NULL;
 209         }
 210 }
 211
 212 /*
 213  * Function to perform cleanup if we get aborted abnormally (e.g., due to a
 214  * dropped connection).
 215  */
 216 void
 217 pty_cleanup_proc(void *session)
 218 {
 219         Session *s=session;
 220         if (s == NULL)
 221                 fatal("pty_cleanup_proc: no session");
 222         debug("pty_cleanup_proc: %s", s->tty);
 223
 224         if (s->pid != 0) {
 225                 /* Record that the user has logged out. */
 226                 record_logout(s->pid, s->tty);
 227         }
 228
 229         /* Release the pseudo-tty. */
 230         pty_release(s->tty);
 231 }
 232
 233 /*
 234  * Prepares for an interactive session.  This is called after the user has
 235  * been successfully authenticated.  During this message exchange, pseudo
 236  * terminals are allocated, X11, TCP/IP, and authentication agent forwardings
 237  * are requested, etc.
 238  */
 239 void
 240 do_authenticated1(Authctxt *authctxt)
 241 {
 242         Session *s;
 243         char *command;
 244         int success, type, fd, n_bytes, plen, screen_flag, have_pty = 0;
 245         int compression_level = 0, enable_compression_after_reply = 0;
 246         u_int proto_len, data_len, dlen;
 247
 248         s = session_new();
 249         s->pw = authctxt->pw;
 250
 251         /*
 252          * We stay in this loop until the client requests to execute a shell
 253          * or a command.
 254          */
 255         for (;;) {
 256                 success = 0;
 257
 258                 /* Get a packet from the client. */
 259                 type = packet_read(&plen);
 260
 261                 /* Process the packet. */
 262                 switch (type) {
 263                 case SSH_CMSG_REQUEST_COMPRESSION:
 264                         packet_integrity_check(plen, 4, type);
 265                         compression_level = packet_get_int();
 266                         if (compression_level < 1 || compression_level > 9) {
 267                                 packet_send_debug("Received illegal compression level %d.",
 268                                      compression_level);
 269                                 break;
 270                         }
 271                         /* Enable compression after we have responded with SUCCESS. */
 272                         enable_compression_after_reply = 1;
 273                         success = 1;
 274                         break;
 275
 276                 case SSH_CMSG_REQUEST_PTY:
 277                         if (no_pty_flag) {
 278                                 debug("Allocating a pty not permitted for this authentication.");
 279                                 break;
 280                         }
 281                         if (have_pty)
 282                                 packet_disconnect("Protocol error: you already have a pty.");
 283
 284                         debug("Allocating pty.");
 285
 286                         /* Allocate a pty and open it. */
 287                         if (!pty_allocate(&s->ptyfd, &s->ttyfd, s->tty,
 288                             sizeof(s->tty))) {
 289                                 error("Failed to allocate pty.");
 290                                 break;
 291                         }
 292                         fatal_add_cleanup(pty_cleanup_proc, (void *)s);
 293                         pty_setowner(s->pw, s->tty);
 294
 295                         /* Get TERM from the packet.  Note that the value may be of arbitrary length. */
 296                         s->term = packet_get_string(&dlen);
 297                         packet_integrity_check(dlen, strlen(s->term), type);
 298                         /* packet_integrity_check(plen, 4 + dlen + 4*4 + n_bytes, type); */
 299                         /* Remaining bytes */
 300                         n_bytes = plen - (4 + dlen + 4 * 4);
 301
 302                         if (strcmp(s->term, "") == 0) {
 303                                 xfree(s->term);
 304                                 s->term = NULL;
 305                         }
 306                         /* Get window size from the packet. */
 307                         s->row = packet_get_int();
 308                         s->col = packet_get_int();
 309                         s->xpixel = packet_get_int();
 310                         s->ypixel = packet_get_int();
 311                         pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
 312
 313                         /* Get tty modes from the packet. */
 314                         tty_parse_modes(s->ttyfd, &n_bytes);
 315                         packet_integrity_check(plen, 4 + dlen + 4 * 4 + n_bytes, type);
 316
 317                         session_proctitle(s);
 318
 319                         /* Indicate that we now have a pty. */
 320                         success = 1;
 321                         have_pty = 1;
 322                         break;
 323
 324                 case SSH_CMSG_X11_REQUEST_FORWARDING:
 325                         if (!options.x11_forwarding) {
 326                                 packet_send_debug("X11 forwarding disabled in server configuration file.");
 327                                 break;
 328                         }
 329                         if (!options.xauth_location) {
 330                                 packet_send_debug("No xauth program; cannot forward with spoofing.");
 331                                 break;
 332                         }
 333                         if (no_x11_forwarding_flag) {
 334                                 packet_send_debug("X11 forwarding not permitted for this authentication.");
 335                                 break;
 336                         }
 337                         debug("Received request for X11 forwarding with auth spoofing.");
 338                         if (s->display != NULL)
 339                                 packet_disconnect("Protocol error: X11 display already set.");
 340
 341                         s->auth_proto = packet_get_string(&proto_len);
 342                         s->auth_data = packet_get_string(&data_len);
 343
 344                         screen_flag = packet_get_protocol_flags() &
 345                             SSH_PROTOFLAG_SCREEN_NUMBER;
 346                         debug2("SSH_PROTOFLAG_SCREEN_NUMBER: %d", screen_flag);
 347
 348                         if (packet_remaining() == 4) {
 349                                 if (!screen_flag)
 350                                         debug2("Buggy client: "
 351                                             "X11 screen flag missing");
 352                                 packet_integrity_check(plen,
 353                                     4 + proto_len + 4 + data_len + 4, type);
 354                                 s->screen = packet_get_int();
 355                         } else {
 356                                 packet_integrity_check(plen,
 357                                     4 + proto_len + 4 + data_len, type);
 358                                 s->screen = 0;
 359                         }
 360                         s->display = x11_create_display_inet(s->screen, options.x11_display_offset);
 361
 362                         if (s->display == NULL)
 363                                 break;
 364
 365                         /* Setup to always have a local .Xauthority. */
 366                         xauthfile = xmalloc(MAXPATHLEN);
 367                         strlcpy(xauthfile, "/tmp/ssh-XXXXXXXX", MAXPATHLEN);
 368                         temporarily_use_uid(s->pw);
 369                         if (mkdtemp(xauthfile) == NULL) {
 370                                 restore_uid();
 371                                 error("private X11 dir: mkdtemp %s failed: %s",
 372                                     xauthfile, strerror(errno));
 373                                 xfree(xauthfile);
 374                                 xauthfile = NULL;
 375                                 /* XXXX remove listening channels */
 376                                 break;
 377                         }
 378                         strlcat(xauthfile, "/cookies", MAXPATHLEN);
 379                         fd = open(xauthfile, O_RDWR|O_CREAT|O_EXCL, 0600);
 380                         if (fd >= 0)
 381                                 close(fd);
 382                         restore_uid();
 383                         fatal_add_cleanup(xauthfile_cleanup_proc, NULL);
 384                         success = 1;
 385                         break;
 386
 387                 case SSH_CMSG_AGENT_REQUEST_FORWARDING:
 388                         if (no_agent_forwarding_flag || compat13) {
 389                                 debug("Authentication agent forwarding not permitted for this authentication.");
 390                                 break;
 391                         }
 392                         debug("Received authentication agent forwarding request.");
 393                         success = auth_input_request_forwarding(s->pw);
 394                         break;
 395
 396                 case SSH_CMSG_PORT_FORWARD_REQUEST:
 397                         if (no_port_forwarding_flag) {
 398                                 debug("Port forwarding not permitted for this authentication.");
 399                                 break;
 400                         }
 401                         if (!options.allow_tcp_forwarding) {
 402                                 debug("Port forwarding not permitted.");
 403                                 break;
 404                         }
 405                         debug("Received TCP/IP port forwarding request.");
 406                         channel_input_port_forward_request(s->pw->pw_uid == 0, options.gateway_ports);
 407                         success = 1;
 408                         break;
 409
 410                 case SSH_CMSG_MAX_PACKET_SIZE:
 411                         if (packet_set_maxsize(packet_get_int()) > 0)
 412                                 success = 1;
 413                         break;
 414
 415                 case SSH_CMSG_EXEC_SHELL:
 416                 case SSH_CMSG_EXEC_CMD:
 417                         if (type == SSH_CMSG_EXEC_CMD) {
 418                                 command = packet_get_string(&dlen);
 419                                 debug("Exec command '%.500s'", command);
 420                                 packet_integrity_check(plen, 4 + dlen, type);
 421                         } else {
 422                                 command = NULL;
 423                                 packet_integrity_check(plen, 0, type);
 424                         }
 425                         if (forced_command != NULL) {
 426                                 original_command = command;
 427                                 command = forced_command;
 428                                 debug("Forced command '%.500s'", forced_command);
 429                         }
 430                         if (have_pty)
 431                                 do_exec_pty(s, command);
 432                         else
 433                                 do_exec_no_pty(s, command);
 434
 435                         if (command != NULL)
 436                                 xfree(command);
 437                         /* Cleanup user's local Xauthority file. */
 438                         if (xauthfile)
 439                                 xauthfile_cleanup_proc(NULL);
 440                         return;
 441
 442                 default:
 443                         /*
 444                          * Any unknown messages in this phase are ignored,
 445                          * and a failure message is returned.
 446                          */
 447                         log("Unknown packet type received after authentication: %d", type);
 448                 }
 449                 packet_start(success ? SSH_SMSG_SUCCESS : SSH_SMSG_FAILURE);
 450                 packet_send();
 451                 packet_write_wait();
 452
 453                 /* Enable compression now that we have replied if appropriate. */
 454                 if (enable_compression_after_reply) {
 455                         enable_compression_after_reply = 0;
 456                         packet_start_compression(compression_level);
 457                 }
 458         }
 459 }
 460
 461 /*
 462  * This is called to fork and execute a command when we have no tty.  This
 463  * will call do_child from the child, and server_loop from the parent after
 464  * setting up file descriptors and such.
 465  */
 466 void
 467 do_exec_no_pty(Session *s, const char *command)
 468 {
 469         int pid;
 470
 471 #ifdef USE_PIPES
 472         int pin[2], pout[2], perr[2];
 473         /* Allocate pipes for communicating with the program. */
 474         if (pipe(pin) < 0 || pipe(pout) < 0 || pipe(perr) < 0)
 475                 packet_disconnect("Could not create pipes: %.100s",
 476                                   strerror(errno));
 477 #else /* USE_PIPES */
 478         int inout[2], err[2];
 479         /* Uses socket pairs to communicate with the program. */
 480         if (socketpair(AF_UNIX, SOCK_STREAM, 0, inout) < 0 ||
 481             socketpair(AF_UNIX, SOCK_STREAM, 0, err) < 0)
 482                 packet_disconnect("Could not create socket pairs: %.100s",
 483                                   strerror(errno));
 484 #endif /* USE_PIPES */
 485         if (s == NULL)
 486                 fatal("do_exec_no_pty: no session");
 487
 488         session_proctitle(s);
 489
 490 #if defined(USE_PAM)
 491         do_pam_setcred(1);
 492 #endif /* USE_PAM */
 493
 494         /* Fork the child. */
 495         if ((pid = fork()) == 0) {
 496                 /* Child.  Reinitialize the log since the pid has changed. */
 497                 log_init(__progname, options.log_level, options.log_facility, log_stderr);
 498
 499                 /*
 500                  * Create a new session and process group since the 4.4BSD
 501                  * setlogin() affects the entire process group.
 502                  */
 503                 if (setsid() < 0)
 504                         error("setsid failed: %.100s", strerror(errno));
 505
 506 #ifdef USE_PIPES
 507                 /*
 508                  * Redirect stdin.  We close the parent side of the socket
 509                  * pair, and make the child side the standard input.
 510                  */
 511                 close(pin[1]);
 512                 if (dup2(pin[0], 0) < 0)
 513                         perror("dup2 stdin");
 514                 close(pin[0]);
 515
 516                 /* Redirect stdout. */
 517                 close(pout[0]);
 518                 if (dup2(pout[1], 1) < 0)
 519                         perror("dup2 stdout");
 520                 close(pout[1]);
 521
 522                 /* Redirect stderr. */
 523                 close(perr[0]);
 524                 if (dup2(perr[1], 2) < 0)
 525                         perror("dup2 stderr");
 526                 close(perr[1]);
 527 #else /* USE_PIPES */
 528                 /*
 529                  * Redirect stdin, stdout, and stderr.  Stdin and stdout will
 530                  * use the same socket, as some programs (particularly rdist)
 531                  * seem to depend on it.
 532                  */
 533                 close(inout[1]);
 534                 close(err[1]);
 535                 if (dup2(inout[0], 0) < 0)      /* stdin */
 536                         perror("dup2 stdin");
 537                 if (dup2(inout[0], 1) < 0)      /* stdout.  Note: same socket as stdin. */
 538                         perror("dup2 stdout");
 539                 if (dup2(err[0], 2) < 0)        /* stderr */
 540                         perror("dup2 stderr");
 541 #endif /* USE_PIPES */
 542
 543                 /* Do processing for the child (exec command etc). */
 544                 do_child(s, command);
 545                 /* NOTREACHED */
 546         }
 547 #ifdef HAVE_CYGWIN
 548         if (is_winnt)
 549                 cygwin_set_impersonation_token(INVALID_HANDLE_VALUE);
 550 #endif
 551         if (pid < 0)
 552                 packet_disconnect("fork failed: %.100s", strerror(errno));
 553         s->pid = pid;
 554         /* Set interactive/non-interactive mode. */
 555         packet_set_interactive(s->display != NULL);
 556 #ifdef USE_PIPES
 557         /* We are the parent.  Close the child sides of the pipes. */
 558         close(pin[0]);
 559         close(pout[1]);
 560         close(perr[1]);
 561
 562         if (compat20) {
 563                 session_set_fds(s, pin[1], pout[0], s->is_subsystem ? -1 : perr[0]);
 564         } else {
 565                 /* Enter the interactive session. */
 566                 server_loop(pid, pin[1], pout[0], perr[0]);
 567                 /* server_loop has closed pin[1], pout[0], and perr[0]. */
 568         }
 569 #else /* USE_PIPES */
 570         /* We are the parent.  Close the child sides of the socket pairs. */
 571         close(inout[0]);
 572         close(err[0]);
 573
 574         /*
 575          * Enter the interactive session.  Note: server_loop must be able to
 576          * handle the case that fdin and fdout are the same.
 577          */
 578         if (compat20) {
 579                 session_set_fds(s, inout[1], inout[1], s->is_subsystem ? -1 : err[1]);
 580         } else {
 581                 server_loop(pid, inout[1], inout[1], err[1]);
 582                 /* server_loop has closed inout[1] and err[1]. */
 583         }
 584 #endif /* USE_PIPES */
 585 }
 586
 587 /*
 588  * This is called to fork and execute a command when we have a tty.  This
 589  * will call do_child from the child, and server_loop from the parent after
 590  * setting up file descriptors, controlling tty, updating wtmp, utmp,
 591  * lastlog, and other such operations.
 592  */
 593 void
 594 do_exec_pty(Session *s, const char *command)
 595 {
 596         int fdout, ptyfd, ttyfd, ptymaster;
 597         pid_t pid;
 598
 599         if (s == NULL)
 600                 fatal("do_exec_pty: no session");
 601         ptyfd = s->ptyfd;
 602         ttyfd = s->ttyfd;
 603
 604 #if defined(USE_PAM)
 605         do_pam_session(s->pw->pw_name, s->tty);
 606         do_pam_setcred(1);
 607 #endif
 608
 609         /* Fork the child. */
 610         if ((pid = fork()) == 0) {
 611                 /* Child.  Reinitialize the log because the pid has changed. */
 612                 log_init(__progname, options.log_level, options.log_facility, log_stderr);
 613
 614                 /* Close the master side of the pseudo tty. */
 615                 close(ptyfd);
 616
 617                 /* Make the pseudo tty our controlling tty. */
 618                 pty_make_controlling_tty(&ttyfd, s->tty);
 619
 620                 /* Redirect stdin from the pseudo tty. */
 621                 if (dup2(ttyfd, fileno(stdin)) < 0)
 622                         error("dup2 stdin failed: %.100s", strerror(errno));
 623
 624                 /* Redirect stdout to the pseudo tty. */
 625                 if (dup2(ttyfd, fileno(stdout)) < 0)
 626                         error("dup2 stdin failed: %.100s", strerror(errno));
 627
 628                 /* Redirect stderr to the pseudo tty. */
 629                 if (dup2(ttyfd, fileno(stderr)) < 0)
 630                         error("dup2 stdin failed: %.100s", strerror(errno));
 631
 632                 /* Close the extra descriptor for the pseudo tty. */
 633                 close(ttyfd);
 634
 635                 /* record login, etc. similar to login(1) */
 636                 if (!(options.use_login && command == NULL))
 637                         do_login(s, command);
 638
 639                 /* Do common processing for the child, such as execing the command. */
 640                 do_child(s, command);
 641                 /* NOTREACHED */
 642         }
 643 #ifdef HAVE_CYGWIN
 644         if (is_winnt)
 645                 cygwin_set_impersonation_token(INVALID_HANDLE_VALUE);
 646 #endif
 647         if (pid < 0)
 648                 packet_disconnect("fork failed: %.100s", strerror(errno));
 649         s->pid = pid;
 650
 651         /* Parent.  Close the slave side of the pseudo tty. */
 652         close(ttyfd);
 653
 654         /*
 655          * Create another descriptor of the pty master side for use as the
 656          * standard input.  We could use the original descriptor, but this
 657          * simplifies code in server_loop.  The descriptor is bidirectional.
 658          */
 659         fdout = dup(ptyfd);
 660         if (fdout < 0)
 661                 packet_disconnect("dup #1 failed: %.100s", strerror(errno));
 662
 663         /* we keep a reference to the pty master */
 664         ptymaster = dup(ptyfd);
 665         if (ptymaster < 0)
 666                 packet_disconnect("dup #2 failed: %.100s", strerror(errno));
 667         s->ptymaster = ptymaster;
 668
 669         /* Enter interactive session. */
 670         packet_set_interactive(1);
 671         if (compat20) {
 672                 session_set_fds(s, ptyfd, fdout, -1);
 673         } else {
 674                 server_loop(pid, ptyfd, fdout, -1);
 675                 /* server_loop _has_ closed ptyfd and fdout. */
 676                 session_pty_cleanup(s);
 677         }
 678 }
 679
 680 /* administrative, login(1)-like work */
 681 void
 682 do_login(Session *s, const char *command)
 683 {
 684         FILE *f;
 685         char *time_string;
 686         char buf[256];
 687         char hostname[MAXHOSTNAMELEN];
 688         socklen_t fromlen;
 689         struct sockaddr_storage from;
 690         struct stat st;
 691         time_t last_login_time;
 692         struct passwd * pw = s->pw;
 693         pid_t pid = getpid();
 694
 695         /*
 696          * Get IP address of client. If the connection is not a socket, let
 697          * the address be 0.0.0.0.
 698          */
 699         memset(&from, 0, sizeof(from));
 700         if (packet_connection_is_on_socket()) {
 701                 fromlen = sizeof(from);
 702                 if (getpeername(packet_get_connection_in(),
 703                      (struct sockaddr *) & from, &fromlen) < 0) {
 704                         debug("getpeername: %.100s", strerror(errno));
 705                         fatal_cleanup();
 706                 }
 707         }
 708
 709         /* Get the time and hostname when the user last logged in. */
 710         if (options.print_lastlog) {
 711                 hostname[0] = '\0';
 712                 last_login_time = get_last_login_time(pw->pw_uid, pw->pw_name,
 713                     hostname, sizeof(hostname));
 714         }
 715
 716         /* Record that there was a login on that tty from the remote host. */
 717         record_login(pid, s->tty, pw->pw_name, pw->pw_uid,
 718             get_remote_name_or_ip(utmp_len, options.reverse_mapping_check),
 719             (struct sockaddr *)&from);
 720
 721 #ifdef USE_PAM
 722         /*
 723          * If password change is needed, do it now.
 724          * This needs to occur before the ~/.hushlogin check.
 725          */
 726         if (is_pam_password_change_required()) {
 727                 print_pam_messages();
 728                 do_pam_chauthtok();
 729         }
 730 #endif
 731
 732         /* Done if .hushlogin exists or a command given. */
 733         if (command != NULL)
 734                 return;
 735         snprintf(buf, sizeof(buf), "%.200s/.hushlogin", pw->pw_dir);
 736 #ifdef HAVE_LOGIN_CAP
 737         if (login_getcapbool(lc, "hushlogin", 0) || stat(buf, &st) >= 0)
 738 #else
 739         if (stat(buf, &st) >= 0)
 740 #endif
 741                 return;
 742
 743 #ifdef USE_PAM
 744         if (!is_pam_password_change_required())
 745                 print_pam_messages();
 746 #endif /* USE_PAM */
 747 #ifdef WITH_AIXAUTHENTICATE
 748         if (aixloginmsg && *aixloginmsg)
 749                 printf("%s\n", aixloginmsg);
 750 #endif /* WITH_AIXAUTHENTICATE */
 751
 752         if (options.print_lastlog && last_login_time != 0) {
 753                 time_string = ctime(&last_login_time);
 754                 if (strchr(time_string, '\n'))
 755                         *strchr(time_string, '\n') = 0;
 756                 if (strcmp(hostname, "") == 0)
 757                         printf("Last login: %s\r\n", time_string);
 758                 else
 759                         printf("Last login: %s from %s\r\n", time_string, hostname);
 760         }
 761         if (options.print_motd) {
 762 #ifdef HAVE_LOGIN_CAP
 763                 f = fopen(login_getcapstr(lc, "welcome", "/etc/motd",
 764                     "/etc/motd"), "r");
 765 #else
 766                 f = fopen("/etc/motd", "r");
 767 #endif
 768                 if (f) {
 769                         while (fgets(buf, sizeof(buf), f))
 770                                 fputs(buf, stdout);
 771                         fclose(f);
 772                 }
 773         }
 774 }
 775
 776 /*
 777  * Sets the value of the given variable in the environment.  If the variable
 778  * already exists, its value is overriden.
 779  */
 780 void
 781 child_set_env(char ***envp, u_int *envsizep, const char *name,
 782               const char *value)
 783 {
 784         u_int i, namelen;
 785         char **env;
 786
 787         /*
 788          * Find the slot where the value should be stored.  If the variable
 789          * already exists, we reuse the slot; otherwise we append a new slot
 790          * at the end of the array, expanding if necessary.
 791          */
 792         env = *envp;
 793         namelen = strlen(name);
 794         for (i = 0; env[i]; i++)
 795                 if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=')
 796                         break;
 797         if (env[i]) {
 798                 /* Reuse the slot. */
 799                 xfree(env[i]);
 800         } else {
 801                 /* New variable.  Expand if necessary. */
 802                 if (i >= (*envsizep) - 1) {
 803                         (*envsizep) += 50;
 804                         env = (*envp) = xrealloc(env, (*envsizep) * sizeof(char *));
 805                 }
 806                 /* Need to set the NULL pointer at end of array beyond the new slot. */
 807                 env[i + 1] = NULL;
 808         }
 809
 810         /* Allocate space and format the variable in the appropriate slot. */
 811         env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1);
 812         snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value);
 813 }
 814
 815 /*
 816  * Reads environment variables from the given file and adds/overrides them
 817  * into the environment.  If the file does not exist, this does nothing.
 818  * Otherwise, it must consist of empty lines, comments (line starts with '#')
 819  * and assignments of the form name=value.  No other forms are allowed.
 820  */
 821 void
 822 read_environment_file(char ***env, u_int *envsize,
 823                       const char *filename)
 824 {
 825         FILE *f;
 826         char buf[4096];
 827         char *cp, *value;
 828
 829         f = fopen(filename, "r");
 830         if (!f)
 831                 return;
 832
 833         while (fgets(buf, sizeof(buf), f)) {
 834                 for (cp = buf; *cp == ' ' || *cp == '\t'; cp++)
 835                         ;
 836                 if (!*cp || *cp == '#' || *cp == '\n')
 837                         continue;
 838                 if (strchr(cp, '\n'))
 839                         *strchr(cp, '\n') = '\0';
 840                 value = strchr(cp, '=');
 841                 if (value == NULL) {
 842                         fprintf(stderr, "Bad line in %.100s: %.200s\n", filename, buf);
 843                         continue;
 844                 }
 845                 /*
 846                  * Replace the equals sign by nul, and advance value to
 847                  * the value string.
 848                  */
 849                 *value = '\0';
 850                 value++;
 851                 child_set_env(env, envsize, cp, value);
 852         }
 853         fclose(f);
 854 }
 855
 856 #ifdef USE_PAM
 857 /*
 858  * Sets any environment variables which have been specified by PAM
 859  */
 860 void do_pam_environment(char ***env, int *envsize)
 861 {
 862         char *equals, var_name[512], var_val[512];
 863         char **pam_env;
 864         int i;
 865
 866         if ((pam_env = fetch_pam_environment()) == NULL)
 867                 return;
 868
 869         for(i = 0; pam_env[i] != NULL; i++) {
 870                 if ((equals = strstr(pam_env[i], "=")) == NULL)
 871                         continue;
 872
 873                 if (strlen(pam_env[i]) < (sizeof(var_name) - 1)) {
 874                         memset(var_name, '\0', sizeof(var_name));
 875                         memset(var_val, '\0', sizeof(var_val));
 876
 877                         strncpy(var_name, pam_env[i], equals - pam_env[i]);
 878                         strcpy(var_val, equals + 1);
 879
 880                         debug3("PAM environment: %s=%s", var_name, var_val);
 881
 882                         child_set_env(env, envsize, var_name, var_val);
 883                 }
 884         }
 885 }
 886 #endif /* USE_PAM */
 887
 888 #ifdef HAVE_CYGWIN
 889 void copy_environment(char ***env, int *envsize)
 890 {
 891         char *equals, var_name[512], var_val[512];
 892         int i;
 893
 894         for(i = 0; environ[i] != NULL; i++) {
 895                 if ((equals = strstr(environ[i], "=")) == NULL)
 896                         continue;
 897
 898                 if (strlen(environ[i]) < (sizeof(var_name) - 1)) {
 899                         memset(var_name, '\0', sizeof(var_name));
 900                         memset(var_val, '\0', sizeof(var_val));
 901
 902                         strncpy(var_name, environ[i], equals - environ[i]);
 903                         strcpy(var_val, equals + 1);
 904
 905                         debug3("Copy environment: %s=%s", var_name, var_val);
 906
 907                         child_set_env(env, envsize, var_name, var_val);
 908                 }
 909         }
 910 }
 911 #endif
 912
 913 #if defined(HAVE_GETUSERATTR)
 914 /*
 915  * AIX-specific login initialisation
 916  */
 917 void set_limit(char *user, char *soft, char *hard, int resource, int mult)
 918 {
 919         struct rlimit rlim;
 920         int slim, hlim;
 921
 922         getrlimit(resource, &rlim);
 923
 924         slim = 0;
 925         if (getuserattr(user, soft, &slim, SEC_INT) != -1) {
 926                 if (slim < 0) {
 927                         rlim.rlim_cur = RLIM_INFINITY;
 928                 } else if (slim != 0) {
 929                         /* See the wackiness below */
 930                         if (rlim.rlim_cur == slim * mult)
 931                                 slim = 0;
 932                         else
 933                                 rlim.rlim_cur = slim * mult;
 934                 }
 935         }
 936
 937         hlim = 0;
 938         if (getuserattr(user, hard, &hlim, SEC_INT) != -1) {
 939                 if (hlim < 0) {
 940                         rlim.rlim_max = RLIM_INFINITY;
 941                 } else if (hlim != 0) {
 942                         rlim.rlim_max = hlim * mult;
 943                 }
 944         }
 945
 946         /*
 947          * XXX For cpu and fsize the soft limit is set to the hard limit
 948          * if the hard limit is left at its default value and the soft limit
 949          * is changed from its default value, either by requesting it
 950          * (slim == 0) or by setting it to the current default.  At least
 951          * that's how rlogind does it.  If you're confused you're not alone.
 952          * Bug or feature? AIX 4.3.1.2
 953          */
 954         if ((!strcmp(soft, "fsize") || !strcmp(soft, "cpu"))
 955             && hlim == 0 && slim != 0)
 956                 rlim.rlim_max = rlim.rlim_cur;
 957         /* A specified hard limit limits the soft limit */
 958         else if (hlim > 0 && rlim.rlim_cur > rlim.rlim_max)
 959                 rlim.rlim_cur = rlim.rlim_max;
 960         /* A soft limit can increase a hard limit */
 961         else if (rlim.rlim_cur > rlim.rlim_max)
 962                 rlim.rlim_max = rlim.rlim_cur;
 963
 964         if (setrlimit(resource, &rlim) != 0)
 965                 error("setrlimit(%.10s) failed: %.100s", soft, strerror(errno));
 966 }
 967
 968 void set_limits_from_userattr(char *user)
 969 {
 970         int mask;
 971         char buf[16];
 972
 973         set_limit(user, S_UFSIZE, S_UFSIZE_HARD, RLIMIT_FSIZE, 512);
 974         set_limit(user, S_UCPU, S_UCPU_HARD, RLIMIT_CPU, 1);
 975         set_limit(user, S_UDATA, S_UDATA_HARD, RLIMIT_DATA, 512);
 976         set_limit(user, S_USTACK, S_USTACK_HARD, RLIMIT_STACK, 512);
 977         set_limit(user, S_URSS, S_URSS_HARD, RLIMIT_RSS, 512);
 978         set_limit(user, S_UCORE, S_UCORE_HARD, RLIMIT_CORE, 512);
 979 #if defined(S_UNOFILE)
 980         set_limit(user, S_UNOFILE, S_UNOFILE_HARD, RLIMIT_NOFILE, 1);
 981 #endif
 982
 983         if (getuserattr(user, S_UMASK, &mask, SEC_INT) != -1) {
 984                 /* Convert decimal to octal */
 985                 (void) snprintf(buf, sizeof(buf), "%d", mask);
 986                 if (sscanf(buf, "%o", &mask) == 1)
 987                         umask(mask);
 988         }
 989 }
 990 #endif /* defined(HAVE_GETUSERATTR) */
 991
 992 /*
 993  * Performs common processing for the child, such as setting up the
 994  * environment, closing extra file descriptors, setting the user and group
 995  * ids, and executing the command or shell.
 996  */
 997 void
 998 do_child(Session *s, const char *command)
 999 {
1000         const char *shell, *hostname = NULL, *cp = NULL;
1001         struct passwd * pw = s->pw;
1002         char buf[256];
1003         char cmd[1024];
1004         FILE *f = NULL;
1005         u_int envsize, i;
1006         char **env;
1007         extern char **environ;
1008         struct stat st;
1009         char *argv[10];
1010         int do_xauth = s->auth_proto != NULL && s->auth_data != NULL;
1011 #ifdef WITH_IRIX_PROJECT
1012         prid_t projid;
1013 #endif /* WITH_IRIX_PROJECT */
1014 #ifdef WITH_IRIX_JOBS
1015         jid_t jid = 0;
1016 #else
1017 #ifdef WITH_IRIX_ARRAY
1018         int jid = 0;
1019 #endif /* WITH_IRIX_ARRAY */
1020 #endif /* WITH_IRIX_JOBS */
1021
1022         /* login(1) is only called if we execute the login shell */
1023         if (options.use_login && command != NULL)
1024                 options.use_login = 0;
1025
1026 #ifndef USE_PAM /* pam_nologin handles this */
1027         if (!options.use_login) {
1028 # ifdef HAVE_LOGIN_CAP
1029                 if (!login_getcapbool(lc, "ignorenologin", 0) && pw->pw_uid)
1030                         f = fopen(login_getcapstr(lc, "nologin", _PATH_NOLOGIN,
1031                             _PATH_NOLOGIN), "r");
1032 # else /* HAVE_LOGIN_CAP */
1033                 if (pw->pw_uid)
1034                         f = fopen(_PATH_NOLOGIN, "r");
1035 # endif /* HAVE_LOGIN_CAP */
1036                 if (f) {
1037                         /* /etc/nologin exists.  Print its contents and exit. */
1038                         while (fgets(buf, sizeof(buf), f))
1039                                 fputs(buf, stderr);
1040                         fclose(f);
1041                         exit(254);
1042                 }
1043         }
1044 #endif /* USE_PAM */
1045
1046         /* Set login name, uid, gid, and groups. */
1047         /* Login(1) does this as well, and it needs uid 0 for the "-h"
1048            switch, so we let login(1) to this for us. */
1049         if (!options.use_login) {
1050 #ifdef HAVE_OSF_SIA
1051                 session_setup_sia(pw->pw_name, s->ttyfd == -1 ? NULL : s->tty);
1052 #else /* HAVE_OSF_SIA */
1053 #ifdef HAVE_CYGWIN
1054                 if (is_winnt) {
1055 #else
1056                 if (getuid() == 0 || geteuid() == 0) {
1057 #endif
1058 # ifdef HAVE_GETUSERATTR
1059                         set_limits_from_userattr(pw->pw_name);
1060 # endif /* HAVE_GETUSERATTR */
1061 # ifdef HAVE_LOGIN_CAP
1062                         if (setusercontext(lc, pw, pw->pw_uid,
1063                             (LOGIN_SETALL & ~LOGIN_SETPATH)) < 0) {
1064                                 perror("unable to set user context");
1065                                 exit(1);
1066                         }
1067 #ifdef BSD_AUTH
1068                         if (auth_approval(NULL, lc, pw->pw_name, "ssh") <= 0) {
1069                                 error("approval failure for %s", pw->pw_name);
1070                                 fprintf(stderr, "Approval failure");
1071                                 exit(1);
1072                         }
1073 #endif
1074 # else /* HAVE_LOGIN_CAP */
1075 #if defined(HAVE_GETLUID) && defined(HAVE_SETLUID)
1076                         /* Sets login uid for accounting */
1077                         if (getluid() == -1 && setluid(pw->pw_uid) == -1)
1078                                 error("setluid: %s", strerror(errno));
1079 #endif /* defined(HAVE_GETLUID) && defined(HAVE_SETLUID) */
1080
1081                         if (setlogin(pw->pw_name) < 0)
1082                                 error("setlogin failed: %s", strerror(errno));
1083                         if (setgid(pw->pw_gid) < 0) {
1084                                 perror("setgid");
1085                                 exit(1);
1086                         }
1087                         /* Initialize the group list. */
1088                         if (initgroups(pw->pw_name, pw->pw_gid) < 0) {
1089                                 perror("initgroups");
1090                                 exit(1);
1091                         }
1092                         endgrent();
1093 #  ifdef USE_PAM
1094                         /*
1095                          * PAM credentials may take the form of
1096                          * supplementary groups. These will have been
1097                          * wiped by the above initgroups() call.
1098                          * Reestablish them here.
1099                          */
1100                         do_pam_setcred(0);
1101 #  endif /* USE_PAM */
1102 #  ifdef WITH_IRIX_JOBS
1103                         jid = jlimit_startjob(pw->pw_name, pw->pw_uid, "interactive");
1104                         if (jid == -1) {
1105                                 fatal("Failed to create job container: %.100s",
1106                                       strerror(errno));
1107                         }
1108 #  endif /* WITH_IRIX_JOBS */
1109 #  ifdef WITH_IRIX_ARRAY
1110                         /* initialize array session */
1111                         if (jid == 0) {
1112                                 if (newarraysess() != 0)
1113                                         fatal("Failed to set up new array session: %.100s",
1114                                               strerror(errno));
1115                         }
1116 #  endif /* WITH_IRIX_ARRAY */
1117 #  ifdef WITH_IRIX_PROJECT
1118                         /* initialize irix project info */
1119                         if ((projid = getdfltprojuser(pw->pw_name)) == -1) {
1120                           debug("Failed to get project id, using projid 0");
1121                           projid = 0;
1122                         }
1123                         if (setprid(projid))
1124                           fatal("Failed to initialize project %d for %s: %.100s",
1125                                 (int)projid, pw->pw_name, strerror(errno));
1126 #  endif /* WITH_IRIX_PROJECT */
1127 #ifdef WITH_IRIX_AUDIT
1128                         if (sysconf(_SC_AUDIT)) {
1129                                 debug("Setting sat id to %d", (int) pw->pw_uid);
1130                                 if (satsetid(pw->pw_uid))
1131                                         debug("error setting satid: %.100s", strerror(errno));
1132                         }
1133 #endif /* WITH_IRIX_AUDIT */
1134
1135 #ifdef _AIX
1136                         /*
1137                          * AIX has a "usrinfo" area where logname and
1138                          * other stuff is stored - a few applications
1139                          * actually use this and die if it's not set
1140                          */
1141                         if (s->ttyfd == -1)
1142                                 s->tty[0] = '\0';
1143                         cp = xmalloc(22 + strlen(s->tty) +
1144                             2 * strlen(pw->pw_name));
1145                         i = sprintf(cp, "LOGNAME=%s%cNAME=%s%cTTY=%s%c%c",
1146                             pw->pw_name, 0, pw->pw_name, 0, s->tty, 0, 0);
1147                         if (usrinfo(SETUINFO, cp, i) == -1)
1148                                 fatal("Couldn't set usrinfo: %s",
1149                                     strerror(errno));
1150                         debug3("AIX/UsrInfo: set len %d", i);
1151                         xfree(cp);
1152 #endif
1153
1154                         /* Permanently switch to the desired uid. */
1155                         permanently_set_uid(pw);
1156 # endif /* HAVE_LOGIN_CAP */
1157                 }
1158 #endif /* HAVE_OSF_SIA */
1159
1160 #ifdef HAVE_CYGWIN
1161                 if (is_winnt)
1162 #endif
1163                 if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid)
1164                         fatal("Failed to set uids to %u.", (u_int) pw->pw_uid);
1165         }
1166         /*
1167          * Get the shell from the password data.  An empty shell field is
1168          * legal, and means /bin/sh.
1169          */
1170         shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
1171 #ifdef HAVE_LOGIN_CAP
1172         shell = login_getcapstr(lc, "shell", (char *)shell, (char *)shell);
1173 #endif
1174
1175 #ifdef AFS
1176         /* Try to get AFS tokens for the local cell. */
1177         if (k_hasafs()) {
1178                 char cell[64];
1179
1180                 if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0)
1181                         krb_afslog(cell, 0);
1182
1183                 krb_afslog(0, 0);
1184         }
1185 #endif /* AFS */
1186
1187         /* Initialize the environment. */
1188         envsize = 100;
1189         env = xmalloc(envsize * sizeof(char *));
1190         env[0] = NULL;
1191
1192 #ifdef HAVE_CYGWIN
1193         /*
1194          * The Windows environment contains some setting which are
1195          * important for a running system. They must not be dropped.
1196          */
1197         copy_environment(&env, &envsize);
1198 #endif
1199
1200         if (!options.use_login) {
1201                 /* Set basic environment. */
1202                 child_set_env(&env, &envsize, "USER", pw->pw_name);
1203                 child_set_env(&env, &envsize, "LOGNAME", pw->pw_name);
1204                 child_set_env(&env, &envsize, "HOME", pw->pw_dir);
1205 #ifdef HAVE_LOGIN_CAP
1206                 (void) setusercontext(lc, pw, pw->pw_uid, LOGIN_SETPATH);
1207                 child_set_env(&env, &envsize, "PATH", getenv("PATH"));
1208 #else /* HAVE_LOGIN_CAP */
1209 # ifndef HAVE_CYGWIN
1210                 /*
1211                  * There's no standard path on Windows. The path contains
1212                  * important components pointing to the system directories,
1213                  * needed for loading shared libraries. So the path better
1214                  * remains intact here.
1215                  */
1216                 child_set_env(&env, &envsize, "PATH", _PATH_STDPATH);
1217 # endif /* HAVE_CYGWIN */
1218 #endif /* HAVE_LOGIN_CAP */
1219
1220                 snprintf(buf, sizeof buf, "%.200s/%.50s",
1221                          _PATH_MAILDIR, pw->pw_name);
1222                 child_set_env(&env, &envsize, "MAIL", buf);
1223
1224                 /* Normal systems set SHELL by default. */
1225                 child_set_env(&env, &envsize, "SHELL", shell);
1226         }
1227         if (getenv("TZ"))
1228                 child_set_env(&env, &envsize, "TZ", getenv("TZ"));
1229
1230         /* Set custom environment options from RSA authentication. */
1231         while (custom_environment) {
1232                 struct envstring *ce = custom_environment;
1233                 char *s = ce->s;
1234                 int i;
1235                 for (i = 0; s[i] != '=' && s[i]; i++);
1236                 if (s[i] == '=') {
1237                         s[i] = 0;
1238                         child_set_env(&env, &envsize, s, s + i + 1);
1239                 }
1240                 custom_environment = ce->next;
1241                 xfree(ce->s);
1242                 xfree(ce);
1243         }
1244
1245         snprintf(buf, sizeof buf, "%.50s %d %d",
1246                  get_remote_ipaddr(), get_remote_port(), get_local_port());
1247         child_set_env(&env, &envsize, "SSH_CLIENT", buf);
1248
1249         if (s->ttyfd != -1)
1250                 child_set_env(&env, &envsize, "SSH_TTY", s->tty);
1251         if (s->term)
1252                 child_set_env(&env, &envsize, "TERM", s->term);
1253         if (s->display)
1254                 child_set_env(&env, &envsize, "DISPLAY", s->display);
1255         if (original_command)
1256                 child_set_env(&env, &envsize, "SSH_ORIGINAL_COMMAND",
1257                     original_command);
1258
1259 #ifdef _AIX
1260         if ((cp = getenv("AUTHSTATE")) != NULL)
1261                 child_set_env(&env, &envsize, "AUTHSTATE", cp);
1262         if ((cp = getenv("KRB5CCNAME")) != NULL)
1263                 child_set_env(&env, &envsize, "KRB5CCNAME", cp);
1264         read_environment_file(&env, &envsize, "/etc/environment");
1265 #endif
1266
1267 #ifdef KRB4
1268         {
1269                 extern char *ticket;
1270
1271                 if (ticket)
1272                         child_set_env(&env, &envsize, "KRBTKFILE", ticket);
1273         }
1274 #endif /* KRB4 */
1275
1276 #ifdef USE_PAM
1277         /* Pull in any environment variables that may have been set by PAM. */
1278         do_pam_environment(&env, &envsize);
1279 #endif /* USE_PAM */
1280
1281         if (xauthfile)
1282                 child_set_env(&env, &envsize, "XAUTHORITY", xauthfile);
1283         if (auth_get_socket_name() != NULL)
1284                 child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME,
1285                               auth_get_socket_name());
1286
1287         /* read $HOME/.ssh/environment. */
1288         if (!options.use_login) {
1289                 snprintf(buf, sizeof buf, "%.200s/.ssh/environment",
1290                     pw->pw_dir);
1291                 read_environment_file(&env, &envsize, buf);
1292         }
1293         if (debug_flag) {
1294                 /* dump the environment */
1295                 fprintf(stderr, "Environment:\n");
1296                 for (i = 0; env[i]; i++)
1297                         fprintf(stderr, "  %.200s\n", env[i]);
1298         }
1299         /* we have to stash the hostname before we close our socket. */
1300         if (options.use_login)
1301                 hostname = get_remote_name_or_ip(utmp_len,
1302                     options.reverse_mapping_check);
1303         /*
1304          * Close the connection descriptors; note that this is the child, and
1305          * the server will still have the socket open, and it is important
1306          * that we do not shutdown it.  Note that the descriptors cannot be
1307          * closed before building the environment, as we call
1308          * get_remote_ipaddr there.
1309          */
1310         if (packet_get_connection_in() == packet_get_connection_out())
1311                 close(packet_get_connection_in());
1312         else {
1313                 close(packet_get_connection_in());
1314                 close(packet_get_connection_out());
1315         }
1316         /*
1317          * Close all descriptors related to channels.  They will still remain
1318          * open in the parent.
1319          */
1320         /* XXX better use close-on-exec? -markus */
1321         channel_close_all();
1322
1323         /*
1324          * Close any extra file descriptors.  Note that there may still be
1325          * descriptors left by system functions.  They will be closed later.
1326          */
1327         endpwent();
1328
1329         /*
1330          * Close any extra open file descriptors so that we don\'t have them
1331          * hanging around in clients.  Note that we want to do this after
1332          * initgroups, because at least on Solaris 2.3 it leaves file
1333          * descriptors open.
1334          */
1335         for (i = 3; i < 64; i++)
1336                 close(i);
1337
1338         /* Change current directory to the user\'s home directory. */
1339         if (chdir(pw->pw_dir) < 0) {
1340                 fprintf(stderr, "Could not chdir to home directory %s: %s\n",
1341                         pw->pw_dir, strerror(errno));
1342 #ifdef HAVE_LOGIN_CAP
1343                 if (login_getcapbool(lc, "requirehome", 0))
1344                         exit(1);
1345 #endif
1346         }
1347
1348         /*
1349          * Must take new environment into use so that .ssh/rc, /etc/sshrc and
1350          * xauth are run in the proper environment.
1351          */
1352         environ = env;
1353
1354         /*
1355          * Run $HOME/.ssh/rc, /etc/sshrc, or xauth (whichever is found first
1356          * in this order).
1357          */
1358         if (!options.use_login) {
1359                 if (stat(_PATH_SSH_USER_RC, &st) >= 0) {
1360                         if (debug_flag)
1361                                 fprintf(stderr, "Running %s %s\n", _PATH_BSHELL,
1362                                     _PATH_SSH_USER_RC);
1363                         f = popen(_PATH_BSHELL " " _PATH_SSH_USER_RC, "w");
1364                         if (f) {
1365                                 if (do_xauth)
1366                                         fprintf(f, "%s %s\n", s->auth_proto,
1367                                             s->auth_data);
1368                                 pclose(f);
1369                         } else
1370                                 fprintf(stderr, "Could not run %s\n",
1371                                     _PATH_SSH_USER_RC);
1372                 } else if (stat(_PATH_SSH_SYSTEM_RC, &st) >= 0) {
1373                         if (debug_flag)
1374                                 fprintf(stderr, "Running %s %s\n", _PATH_BSHELL,
1375                                     _PATH_SSH_SYSTEM_RC);
1376
1377                         f = popen(_PATH_BSHELL " " _PATH_SSH_SYSTEM_RC, "w");
1378                         if (f) {
1379                                 if (do_xauth)
1380                                         fprintf(f, "%s %s\n", s->auth_proto,
1381                                             s->auth_data);
1382                                 pclose(f);
1383                         } else
1384                                 fprintf(stderr, "Could not run %s\n",
1385                                     _PATH_SSH_SYSTEM_RC);
1386                 } else if (do_xauth && options.xauth_location != NULL) {
1387                         /* Add authority data to .Xauthority if appropriate. */
1388                         char *screen = strchr(s->display, ':');
1389
1390                         if (debug_flag) {
1391                                 fprintf(stderr,
1392                                     "Running %.100s add "
1393                                     "%.100s %.100s %.100s\n",
1394                                     options.xauth_location, s->display,
1395                                     s->auth_proto, s->auth_data);
1396                                 if (screen != NULL)
1397                                         fprintf(stderr,
1398                                             "Adding %.*s/unix%s %s %s\n",
1399                                             (int)(screen - s->display),
1400                                             s->display, screen,
1401                                             s->auth_proto, s->auth_data);
1402                         }
1403                         snprintf(cmd, sizeof cmd, "%s -q -",
1404                             options.xauth_location);
1405                         f = popen(cmd, "w");
1406                         if (f) {
1407                                 fprintf(f, "add %s %s %s\n", s->display,
1408                                     s->auth_proto, s->auth_data);
1409                                 if (screen != NULL)
1410                                         fprintf(f, "add %.*s/unix%s %s %s\n",
1411                                             (int)(screen - s->display),
1412                                             s->display, screen,
1413                                             s->auth_proto,
1414                                             s->auth_data);
1415                                 pclose(f);
1416                         } else {
1417                                 fprintf(stderr, "Could not run %s\n",
1418                                     cmd);
1419                         }
1420                 }
1421                 /* Get the last component of the shell name. */
1422                 cp = strrchr(shell, '/');
1423                 if (cp)
1424                         cp++;
1425                 else
1426                         cp = shell;
1427         }
1428
1429         /* restore SIGPIPE for child */
1430         signal(SIGPIPE,  SIG_DFL);
1431
1432         /*
1433          * If we have no command, execute the shell.  In this case, the shell
1434          * name to be passed in argv[0] is preceded by '-' to indicate that
1435          * this is a login shell.
1436          */
1437         if (!command) {
1438                 if (!options.use_login) {
1439                         char buf[256];
1440
1441                         /*
1442                          * Check for mail if we have a tty and it was enabled
1443                          * in server options.
1444                          */
1445                         if (s->ttyfd != -1 && options.check_mail) {
1446                                 char *mailbox;
1447                                 struct stat mailstat;
1448
1449                                 mailbox = getenv("MAIL");
1450                                 if (mailbox != NULL) {
1451                                         if (stat(mailbox, &mailstat) != 0 ||
1452                                             mailstat.st_size == 0)
1453                                                 printf("No mail.\n");
1454                                         else if (mailstat.st_mtime < mailstat.st_atime)
1455                                                 printf("You have mail.\n");
1456                                         else
1457                                                 printf("You have new mail.\n");
1458                                 }
1459                         }
1460                         /* Start the shell.  Set initial character to '-'. */
1461                         buf[0] = '-';
1462                         strncpy(buf + 1, cp, sizeof(buf) - 1);
1463                         buf[sizeof(buf) - 1] = 0;
1464
1465                         /* Execute the shell. */
1466                         argv[0] = buf;
1467                         argv[1] = NULL;
1468                         execve(shell, argv, env);
1469
1470                         /* Executing the shell failed. */
1471                         perror(shell);
1472                         exit(1);
1473
1474                 } else {
1475                         /* Launch login(1). */
1476
1477                         execl(LOGIN_PROGRAM, "login", "-h", hostname,
1478                              "-p", "-f", "--", pw->pw_name, NULL);
1479
1480                         /* Login couldn't be executed, die. */
1481
1482                         perror("login");
1483                         exit(1);
1484                 }
1485         }
1486         /*
1487          * Execute the command using the user's shell.  This uses the -c
1488          * option to execute the command.
1489          */
1490         argv[0] = (char *) cp;
1491         argv[1] = "-c";
1492         argv[2] = (char *) command;
1493         argv[3] = NULL;
1494         execve(shell, argv, env);
1495         perror(shell);
1496         exit(1);
1497 }
1498
1499 Session *
1500 session_new(void)
1501 {
1502         int i;
1503         static int did_init = 0;
1504         if (!did_init) {
1505                 debug("session_new: init");
1506                 for(i = 0; i < MAX_SESSIONS; i++) {
1507                         sessions[i].used = 0;
1508                         sessions[i].self = i;
1509                 }
1510                 did_init = 1;
1511         }
1512         for(i = 0; i < MAX_SESSIONS; i++) {
1513                 Session *s = &sessions[i];
1514                 if (! s->used) {
1515                         memset(s, 0, sizeof(*s));
1516                         s->chanid = -1;
1517                         s->ptyfd = -1;
1518                         s->ttyfd = -1;
1519                         s->used = 1;
1520                         debug("session_new: session %d", i);
1521                         return s;
1522                 }
1523         }
1524         return NULL;
1525 }
1526
1527 void
1528 session_dump(void)
1529 {
1530         int i;
1531         for(i = 0; i < MAX_SESSIONS; i++) {
1532                 Session *s = &sessions[i];
1533                 debug("dump: used %d session %d %p channel %d pid %d",
1534                     s->used,
1535                     s->self,
1536                     s,
1537                     s->chanid,
1538                     s->pid);
1539         }
1540 }
1541
1542 int
1543 session_open(int chanid)
1544 {
1545         Session *s = session_new();
1546         debug("session_open: channel %d", chanid);
1547         if (s == NULL) {
1548                 error("no more sessions");
1549                 return 0;
1550         }
1551         s->pw = auth_get_user();
1552         if (s->pw == NULL)
1553                 fatal("no user for session %d", s->self);
1554         debug("session_open: session %d: link with channel %d", s->self, chanid);
1555         s->chanid = chanid;
1556         return 1;
1557 }
1558
1559 Session *
1560 session_by_channel(int id)
1561 {
1562         int i;
1563         for(i = 0; i < MAX_SESSIONS; i++) {
1564                 Session *s = &sessions[i];
1565                 if (s->used && s->chanid == id) {
1566                         debug("session_by_channel: session %d channel %d", i, id);
1567                         return s;
1568                 }
1569         }
1570         debug("session_by_channel: unknown channel %d", id);
1571         session_dump();
1572         return NULL;
1573 }
1574
1575 Session *
1576 session_by_pid(pid_t pid)
1577 {
1578         int i;
1579         debug("session_by_pid: pid %d", pid);
1580         for(i = 0; i < MAX_SESSIONS; i++) {
1581                 Session *s = &sessions[i];
1582                 if (s->used && s->pid == pid)
1583                         return s;
1584         }
1585         error("session_by_pid: unknown pid %d", pid);
1586         session_dump();
1587         return NULL;
1588 }
1589
1590 int
1591 session_window_change_req(Session *s)
1592 {
1593         s->col = packet_get_int();
1594         s->row = packet_get_int();
1595         s->xpixel = packet_get_int();
1596         s->ypixel = packet_get_int();
1597         packet_done();
1598         pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1599         return 1;
1600 }
1601
1602 int
1603 session_pty_req(Session *s)
1604 {
1605         u_int len;
1606         char *term_modes;       /* encoded terminal modes */
1607
1608         if (no_pty_flag)
1609                 return 0;
1610         if (s->ttyfd != -1)
1611                 return 0;
1612         s->term = packet_get_string(&len);
1613         s->col = packet_get_int();
1614         s->row = packet_get_int();
1615         s->xpixel = packet_get_int();
1616         s->ypixel = packet_get_int();
1617         term_modes = packet_get_string(&len);
1618         packet_done();
1619
1620         if (strcmp(s->term, "") == 0) {
1621                 xfree(s->term);
1622                 s->term = NULL;
1623         }
1624         /* Allocate a pty and open it. */
1625         if (!pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty))) {
1626                 xfree(s->term);
1627                 s->term = NULL;
1628                 s->ptyfd = -1;
1629                 s->ttyfd = -1;
1630                 error("session_pty_req: session %d alloc failed", s->self);
1631                 xfree(term_modes);
1632                 return 0;
1633         }
1634         debug("session_pty_req: session %d alloc %s", s->self, s->tty);
1635         /*
1636          * Add a cleanup function to clear the utmp entry and record logout
1637          * time in case we call fatal() (e.g., the connection gets closed).
1638          */
1639         fatal_add_cleanup(pty_cleanup_proc, (void *)s);
1640         pty_setowner(s->pw, s->tty);
1641         /* Get window size from the packet. */
1642         pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1643
1644         session_proctitle(s);
1645
1646         /* XXX parse and set terminal modes */
1647         xfree(term_modes);
1648         return 1;
1649 }
1650
1651 int
1652 session_subsystem_req(Session *s)
1653 {
1654         u_int len;
1655         int success = 0;
1656         char *subsys = packet_get_string(&len);
1657         int i;
1658
1659         packet_done();
1660         log("subsystem request for %s", subsys);
1661
1662         for (i = 0; i < options.num_subsystems; i++) {
1663                 if(strcmp(subsys, options.subsystem_name[i]) == 0) {
1664                         debug("subsystem: exec() %s", options.subsystem_command[i]);
1665                         s->is_subsystem = 1;
1666                         do_exec_no_pty(s, options.subsystem_command[i]);
1667                         success = 1;
1668                 }
1669         }
1670
1671         if (!success)
1672                 log("subsystem request for %s failed, subsystem not found", subsys);
1673
1674         xfree(subsys);
1675         return success;
1676 }
1677
1678 int
1679 session_x11_req(Session *s)
1680 {
1681         int fd;
1682         if (no_x11_forwarding_flag) {
1683                 debug("X11 forwarding disabled in user configuration file.");
1684                 return 0;
1685         }
1686         if (!options.x11_forwarding) {
1687                 debug("X11 forwarding disabled in server configuration file.");
1688                 return 0;
1689         }
1690         if (xauthfile != NULL) {
1691                 debug("X11 fwd already started.");
1692                 return 0;
1693         }
1694
1695         debug("Received request for X11 forwarding with auth spoofing.");
1696         if (s->display != NULL)
1697                 packet_disconnect("Protocol error: X11 display already set.");
1698
1699         s->single_connection = packet_get_char();
1700         s->auth_proto = packet_get_string(NULL);
1701         s->auth_data = packet_get_string(NULL);
1702         s->screen = packet_get_int();
1703         packet_done();
1704
1705         s->display = x11_create_display_inet(s->screen, options.x11_display_offset);
1706         if (s->display == NULL) {
1707                 xfree(s->auth_proto);
1708                 xfree(s->auth_data);
1709                 return 0;
1710         }
1711         xauthfile = xmalloc(MAXPATHLEN);
1712         strlcpy(xauthfile, "/tmp/ssh-XXXXXXXX", MAXPATHLEN);
1713         temporarily_use_uid(s->pw);
1714         if (mkdtemp(xauthfile) == NULL) {
1715                 restore_uid();
1716                 error("private X11 dir: mkdtemp %s failed: %s",
1717                     xauthfile, strerror(errno));
1718                 xfree(xauthfile);
1719                 xauthfile = NULL;
1720                 xfree(s->auth_proto);
1721                 xfree(s->auth_data);
1722                 /* XXXX remove listening channels */
1723                 return 0;
1724         }
1725         strlcat(xauthfile, "/cookies", MAXPATHLEN);
1726         fd = open(xauthfile, O_RDWR|O_CREAT|O_EXCL, 0600);
1727         if (fd >= 0)
1728                 close(fd);
1729         restore_uid();
1730         fatal_add_cleanup(xauthfile_cleanup_proc, s);
1731         return 1;
1732 }
1733
1734 int
1735 session_shell_req(Session *s)
1736 {
1737         /* if forced_command == NULL, the shell is execed */
1738         char *shell = forced_command;
1739         packet_done();
1740         if (s->ttyfd == -1)
1741                 do_exec_no_pty(s, shell);
1742         else
1743                 do_exec_pty(s, shell);
1744         return 1;
1745 }
1746
1747 int
1748 session_exec_req(Session *s)
1749 {
1750         u_int len;
1751         char *command = packet_get_string(&len);
1752         packet_done();
1753         if (forced_command) {
1754                 original_command = command;
1755                 command = forced_command;
1756                 debug("Forced command '%.500s'", forced_command);
1757         }
1758         if (s->ttyfd == -1)
1759                 do_exec_no_pty(s, command);
1760         else
1761                 do_exec_pty(s, command);
1762         if (forced_command == NULL)
1763                 xfree(command);
1764         return 1;
1765 }
1766
1767 int
1768 session_auth_agent_req(Session *s)
1769 {
1770         static int called = 0;
1771         packet_done();
1772         if (no_agent_forwarding_flag) {
1773                 debug("session_auth_agent_req: no_agent_forwarding_flag");
1774                 return 0;
1775         }
1776         if (called) {
1777                 return 0;
1778         } else {
1779                 called = 1;
1780                 return auth_input_request_forwarding(s->pw);
1781         }
1782 }
1783
1784 void
1785 session_input_channel_req(int id, void *arg)
1786 {
1787         u_int len;
1788         int reply;
1789         int success = 0;
1790         char *rtype;
1791         Session *s;
1792         Channel *c;
1793
1794         rtype = packet_get_string(&len);
1795         reply = packet_get_char();
1796
1797         s = session_by_channel(id);
1798         if (s == NULL)
1799                 fatal("session_input_channel_req: channel %d: no session", id);
1800         c = channel_lookup(id);
1801         if (c == NULL)
1802                 fatal("session_input_channel_req: channel %d: bad channel", id);
1803
1804         debug("session_input_channel_req: session %d channel %d request %s reply %d",
1805             s->self, id, rtype, reply);
1806
1807         /*
1808          * a session is in LARVAL state until a shell, a command
1809          * or a subsystem is executed
1810          */
1811         if (c->type == SSH_CHANNEL_LARVAL) {
1812                 if (strcmp(rtype, "shell") == 0) {
1813                         success = session_shell_req(s);
1814                 } else if (strcmp(rtype, "exec") == 0) {
1815                         success = session_exec_req(s);
1816                 } else if (strcmp(rtype, "pty-req") == 0) {
1817                         success =  session_pty_req(s);
1818                 } else if (strcmp(rtype, "x11-req") == 0) {
1819                         success = session_x11_req(s);
1820                 } else if (strcmp(rtype, "auth-agent-req@openssh.com") == 0) {
1821                         success = session_auth_agent_req(s);
1822                 } else if (strcmp(rtype, "subsystem") == 0) {
1823                         success = session_subsystem_req(s);
1824                 }
1825         }
1826         if (strcmp(rtype, "window-change") == 0) {
1827                 success = session_window_change_req(s);
1828         }
1829
1830         if (reply) {
1831                 packet_start(success ?
1832                     SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1833                 packet_put_int(c->remote_id);
1834                 packet_send();
1835         }
1836         xfree(rtype);
1837 }
1838
1839 void
1840 session_set_fds(Session *s, int fdin, int fdout, int fderr)
1841 {
1842         if (!compat20)
1843                 fatal("session_set_fds: called for proto != 2.0");
1844         /*
1845          * now that have a child and a pipe to the child,
1846          * we can activate our channel and register the fd's
1847          */
1848         if (s->chanid == -1)
1849                 fatal("no channel for session %d", s->self);
1850         channel_set_fds(s->chanid,
1851             fdout, fdin, fderr,
1852             fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ,
1853             1);
1854 }
1855
1856 void
1857 session_pty_cleanup(Session *s)
1858 {
1859         if (s == NULL || s->ttyfd == -1)
1860                 return;
1861
1862         debug("session_pty_cleanup: session %d release %s", s->self, s->tty);
1863
1864         /* Cancel the cleanup function. */
1865         fatal_remove_cleanup(pty_cleanup_proc, (void *)s);
1866
1867         /* Record that the user has logged out. */
1868         record_logout(s->pid, s->tty);
1869
1870         /* Release the pseudo-tty. */
1871         pty_release(s->tty);
1872
1873         /*
1874          * Close the server side of the socket pairs.  We must do this after
1875          * the pty cleanup, so that another process doesn't get this pty
1876          * while we're still cleaning up.
1877          */
1878         if (close(s->ptymaster) < 0)
1879                 error("close(s->ptymaster): %s", strerror(errno));
1880 }
1881
1882 void
1883 session_exit_message(Session *s, int status)
1884 {
1885         Channel *c;
1886         if (s == NULL)
1887                 fatal("session_close: no session");
1888         c = channel_lookup(s->chanid);
1889         if (c == NULL)
1890                 fatal("session_close: session %d: no channel %d",
1891                     s->self, s->chanid);
1892         debug("session_exit_message: session %d channel %d pid %d",
1893             s->self, s->chanid, s->pid);
1894
1895         if (WIFEXITED(status)) {
1896                 channel_request_start(s->chanid,
1897                     "exit-status", 0);
1898                 packet_put_int(WEXITSTATUS(status));
1899                 packet_send();
1900         } else if (WIFSIGNALED(status)) {
1901                 channel_request_start(s->chanid,
1902                     "exit-signal", 0);
1903                 packet_put_int(WTERMSIG(status));
1904 #ifdef WCOREDUMP
1905                 packet_put_char(WCOREDUMP(status));
1906 #else /* WCOREDUMP */
1907                 packet_put_char(0);
1908 #endif /* WCOREDUMP */
1909                 packet_put_cstring("");
1910                 packet_put_cstring("");
1911                 packet_send();
1912         } else {
1913                 /* Some weird exit cause.  Just exit. */
1914                 packet_disconnect("wait returned status %04x.", status);
1915         }
1916
1917         /* disconnect channel */
1918         debug("session_exit_message: release channel %d", s->chanid);
1919         channel_cancel_cleanup(s->chanid);
1920         /*
1921          * emulate a write failure with 'chan_write_failed', nobody will be
1922          * interested in data we write.
1923          * Note that we must not call 'chan_read_failed', since there could
1924          * be some more data waiting in the pipe.
1925          */
1926         if (c->ostate != CHAN_OUTPUT_CLOSED)
1927                 chan_write_failed(c);
1928         s->chanid = -1;
1929 }
1930
1931 void
1932 session_free(Session *s)
1933 {
1934         debug("session_free: session %d pid %d", s->self, s->pid);
1935         if (s->term)
1936                 xfree(s->term);
1937         if (s->display)
1938                 xfree(s->display);
1939         if (s->auth_data)
1940                 xfree(s->auth_data);
1941         if (s->auth_proto)
1942                 xfree(s->auth_proto);
1943         s->used = 0;
1944 }
1945
1946 void
1947 session_close(Session *s)
1948 {
1949         session_pty_cleanup(s);
1950         session_free(s);
1951         session_proctitle(s);
1952 }
1953
1954 void
1955 session_close_by_pid(pid_t pid, int status)
1956 {
1957         Session *s = session_by_pid(pid);
1958         if (s == NULL) {
1959                 debug("session_close_by_pid: no session for pid %d", s->pid);
1960                 return;
1961         }
1962         if (s->chanid != -1)
1963                 session_exit_message(s, status);
1964         session_close(s);
1965 }
1966
1967 /*
1968  * this is called when a channel dies before
1969  * the session 'child' itself dies
1970  */
1971 void
1972 session_close_by_channel(int id, void *arg)
1973 {
1974         Session *s = session_by_channel(id);
1975         if (s == NULL) {
1976                 debug("session_close_by_channel: no session for channel %d", id);
1977                 return;
1978         }
1979         /* disconnect channel */
1980         channel_cancel_cleanup(s->chanid);
1981         s->chanid = -1;
1982
1983         debug("session_close_by_channel: channel %d kill %d", id, s->pid);
1984         if (s->pid == 0) {
1985                 /* close session immediately */
1986                 session_close(s);
1987         } else {
1988                 /* notify child, delay session cleanup */
1989                 if (kill(s->pid, (s->ttyfd == -1) ? SIGTERM : SIGHUP) < 0)
1990                         error("session_close_by_channel: kill %d: %s",
1991                             s->pid, strerror(errno));
1992         }
1993 }
1994
1995 char *
1996 session_tty_list(void)
1997 {
1998         static char buf[1024];
1999         int i;
2000         buf[0] = '\0';
2001         for(i = 0; i < MAX_SESSIONS; i++) {
2002                 Session *s = &sessions[i];
2003                 if (s->used && s->ttyfd != -1) {
2004                         if (buf[0] != '\0')
2005                                 strlcat(buf, ",", sizeof buf);
2006                         strlcat(buf, strrchr(s->tty, '/') + 1, sizeof buf);
2007                 }
2008         }
2009         if (buf[0] == '\0')
2010                 strlcpy(buf, "notty", sizeof buf);
2011         return buf;
2012 }
2013
2014 void
2015 session_proctitle(Session *s)
2016 {
2017         if (s->pw == NULL)
2018                 error("no user for session %d", s->self);
2019         else
2020                 setproctitle("%s@%s", s->pw->pw_name, session_tty_list());
2021 }
2022
2023 void
2024 do_authenticated2(Authctxt *authctxt)
2025 {
2026
2027         server_loop2();
2028         if (xauthfile)
2029                 xauthfile_cleanup_proc(NULL);
2030 }