2 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
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".
11 * SSH2 support by Markus Friedl.
12 * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions
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.
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.
36 RCSID("$OpenBSD: session.c,v 1.181 2004/12/23 17:35:48 markus Exp $");
51 #include "auth-options.h"
52 #include "pathnames.h"
56 #include "serverloop.h"
59 #include "monitor_wrap.h"
61 #if defined(KRB5) && defined(USE_AFS)
71 Session *session_new(void);
72 void session_set_fds(Session *, int, int, int);
73 void session_pty_cleanup(Session *);
74 void session_proctitle(Session *);
75 int session_setup_x11fwd(Session *);
76 void do_exec_pty(Session *, const char *);
77 void do_exec_no_pty(Session *, const char *);
78 void do_exec(Session *, const char *);
79 void do_login(Session *, const char *);
80 #ifdef LOGIN_NEEDS_UTMPX
81 static void do_pre_login(Session *s);
83 void do_child(Session *, const char *);
85 int check_quietlogin(Session *, const char *);
87 static void do_authenticated1(Authctxt *);
88 static void do_authenticated2(Authctxt *);
90 static int session_pty_req(Session *);
93 extern ServerOptions options;
94 extern char *__progname;
95 extern int log_stderr;
96 extern int debug_flag;
97 extern u_int utmp_len;
98 extern int startup_pipe;
99 extern void destroy_sensitive_data(void);
100 extern Buffer loginmsg;
102 /* original command from peer. */
103 const char *original_command = NULL;
106 #define MAX_SESSIONS 10
107 Session sessions[MAX_SESSIONS];
109 #ifdef HAVE_LOGIN_CAP
113 static int is_child = 0;
115 /* Name and directory of socket for authentication agent forwarding. */
116 static char *auth_sock_name = NULL;
117 static char *auth_sock_dir = NULL;
119 /* removes the agent forwarding socket */
122 auth_sock_cleanup_proc(struct passwd *pw)
124 if (auth_sock_name != NULL) {
125 temporarily_use_uid(pw);
126 unlink(auth_sock_name);
127 rmdir(auth_sock_dir);
128 auth_sock_name = NULL;
134 auth_input_request_forwarding(struct passwd * pw)
138 struct sockaddr_un sunaddr;
140 if (auth_sock_name != NULL) {
141 error("authentication forwarding requested twice.");
145 /* Temporarily drop privileged uid for mkdir/bind. */
146 temporarily_use_uid(pw);
148 /* Allocate a buffer for the socket name, and format the name. */
149 auth_sock_name = xmalloc(MAXPATHLEN);
150 auth_sock_dir = xmalloc(MAXPATHLEN);
151 strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN);
153 /* Create private directory for socket */
154 if (mkdtemp(auth_sock_dir) == NULL) {
155 packet_send_debug("Agent forwarding disabled: "
156 "mkdtemp() failed: %.100s", strerror(errno));
158 xfree(auth_sock_name);
159 xfree(auth_sock_dir);
160 auth_sock_name = NULL;
161 auth_sock_dir = NULL;
164 snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%ld",
165 auth_sock_dir, (long) getpid());
167 /* Create the socket. */
168 sock = socket(AF_UNIX, SOCK_STREAM, 0);
170 packet_disconnect("socket: %.100s", strerror(errno));
172 /* Bind it to the name. */
173 memset(&sunaddr, 0, sizeof(sunaddr));
174 sunaddr.sun_family = AF_UNIX;
175 strlcpy(sunaddr.sun_path, auth_sock_name, sizeof(sunaddr.sun_path));
177 if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0)
178 packet_disconnect("bind: %.100s", strerror(errno));
180 /* Restore the privileged uid. */
183 /* Start listening on the socket. */
184 if (listen(sock, SSH_LISTEN_BACKLOG) < 0)
185 packet_disconnect("listen: %.100s", strerror(errno));
187 /* Allocate a channel for the authentication agent socket. */
188 nc = channel_new("auth socket",
189 SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1,
190 CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
191 0, "auth socket", 1);
192 strlcpy(nc->path, auth_sock_name, sizeof(nc->path));
197 display_loginmsg(void)
199 if (buffer_len(&loginmsg) > 0) {
200 buffer_append(&loginmsg, "\0", 1);
201 printf("%s", (char *)buffer_ptr(&loginmsg));
202 buffer_clear(&loginmsg);
207 do_authenticated(Authctxt *authctxt)
209 setproctitle("%s", authctxt->pw->pw_name);
212 * Cancel the alarm we set to limit the time taken for
216 if (startup_pipe != -1) {
220 /* setup the channel layer */
221 if (!no_port_forwarding_flag && options.allow_tcp_forwarding)
222 channel_permit_all_opens();
225 do_authenticated2(authctxt);
227 do_authenticated1(authctxt);
229 do_cleanup(authctxt);
233 * Prepares for an interactive session. This is called after the user has
234 * been successfully authenticated. During this message exchange, pseudo
235 * terminals are allocated, X11, TCP/IP, and authentication agent forwardings
236 * are requested, etc.
239 do_authenticated1(Authctxt *authctxt)
243 int success, type, screen_flag;
244 int enable_compression_after_reply = 0;
245 u_int proto_len, data_len, dlen, compression_level = 0;
249 error("no more sessions");
252 s->authctxt = authctxt;
253 s->pw = authctxt->pw;
256 * We stay in this loop until the client requests to execute a shell
262 /* Get a packet from the client. */
263 type = packet_read();
265 /* Process the packet. */
267 case SSH_CMSG_REQUEST_COMPRESSION:
268 compression_level = packet_get_int();
270 if (compression_level < 1 || compression_level > 9) {
271 packet_send_debug("Received invalid compression level %d.",
275 if (!options.compression) {
276 debug2("compression disabled");
279 /* Enable compression after we have responded with SUCCESS. */
280 enable_compression_after_reply = 1;
284 case SSH_CMSG_REQUEST_PTY:
285 success = session_pty_req(s);
288 case SSH_CMSG_X11_REQUEST_FORWARDING:
289 s->auth_proto = packet_get_string(&proto_len);
290 s->auth_data = packet_get_string(&data_len);
292 screen_flag = packet_get_protocol_flags() &
293 SSH_PROTOFLAG_SCREEN_NUMBER;
294 debug2("SSH_PROTOFLAG_SCREEN_NUMBER: %d", screen_flag);
296 if (packet_remaining() == 4) {
298 debug2("Buggy client: "
299 "X11 screen flag missing");
300 s->screen = packet_get_int();
305 success = session_setup_x11fwd(s);
307 xfree(s->auth_proto);
309 s->auth_proto = NULL;
314 case SSH_CMSG_AGENT_REQUEST_FORWARDING:
315 if (no_agent_forwarding_flag || compat13) {
316 debug("Authentication agent forwarding not permitted for this authentication.");
319 debug("Received authentication agent forwarding request.");
320 success = auth_input_request_forwarding(s->pw);
323 case SSH_CMSG_PORT_FORWARD_REQUEST:
324 if (no_port_forwarding_flag) {
325 debug("Port forwarding not permitted for this authentication.");
328 if (!options.allow_tcp_forwarding) {
329 debug("Port forwarding not permitted.");
332 debug("Received TCP/IP port forwarding request.");
333 channel_input_port_forward_request(s->pw->pw_uid == 0, options.gateway_ports);
337 case SSH_CMSG_MAX_PACKET_SIZE:
338 if (packet_set_maxsize(packet_get_int()) > 0)
342 case SSH_CMSG_EXEC_SHELL:
343 case SSH_CMSG_EXEC_CMD:
344 if (type == SSH_CMSG_EXEC_CMD) {
345 command = packet_get_string(&dlen);
346 debug("Exec command '%.500s'", command);
358 * Any unknown messages in this phase are ignored,
359 * and a failure message is returned.
361 logit("Unknown packet type received after authentication: %d", type);
363 packet_start(success ? SSH_SMSG_SUCCESS : SSH_SMSG_FAILURE);
367 /* Enable compression now that we have replied if appropriate. */
368 if (enable_compression_after_reply) {
369 enable_compression_after_reply = 0;
370 packet_start_compression(compression_level);
376 * This is called to fork and execute a command when we have no tty. This
377 * will call do_child from the child, and server_loop from the parent after
378 * setting up file descriptors and such.
381 do_exec_no_pty(Session *s, const char *command)
386 int pin[2], pout[2], perr[2];
387 /* Allocate pipes for communicating with the program. */
388 if (pipe(pin) < 0 || pipe(pout) < 0 || pipe(perr) < 0)
389 packet_disconnect("Could not create pipes: %.100s",
391 #else /* USE_PIPES */
392 int inout[2], err[2];
393 /* Uses socket pairs to communicate with the program. */
394 if (socketpair(AF_UNIX, SOCK_STREAM, 0, inout) < 0 ||
395 socketpair(AF_UNIX, SOCK_STREAM, 0, err) < 0)
396 packet_disconnect("Could not create socket pairs: %.100s",
398 #endif /* USE_PIPES */
400 fatal("do_exec_no_pty: no session");
402 session_proctitle(s);
405 if (options.use_pam && !use_privsep)
409 /* Fork the child. */
410 if ((pid = fork()) == 0) {
413 /* Child. Reinitialize the log since the pid has changed. */
414 log_init(__progname, options.log_level, options.log_facility, log_stderr);
417 * Create a new session and process group since the 4.4BSD
418 * setlogin() affects the entire process group.
421 error("setsid failed: %.100s", strerror(errno));
425 * Redirect stdin. We close the parent side of the socket
426 * pair, and make the child side the standard input.
429 if (dup2(pin[0], 0) < 0)
430 perror("dup2 stdin");
433 /* Redirect stdout. */
435 if (dup2(pout[1], 1) < 0)
436 perror("dup2 stdout");
439 /* Redirect stderr. */
441 if (dup2(perr[1], 2) < 0)
442 perror("dup2 stderr");
444 #else /* USE_PIPES */
446 * Redirect stdin, stdout, and stderr. Stdin and stdout will
447 * use the same socket, as some programs (particularly rdist)
448 * seem to depend on it.
452 if (dup2(inout[0], 0) < 0) /* stdin */
453 perror("dup2 stdin");
454 if (dup2(inout[0], 1) < 0) /* stdout. Note: same socket as stdin. */
455 perror("dup2 stdout");
456 if (dup2(err[0], 2) < 0) /* stderr */
457 perror("dup2 stderr");
458 #endif /* USE_PIPES */
461 cray_init_job(s->pw); /* set up cray jid and tmpdir */
464 /* Do processing for the child (exec command etc). */
465 do_child(s, command);
469 signal(WJSIGNAL, cray_job_termination_handler);
473 cygwin_set_impersonation_token(INVALID_HANDLE_VALUE);
476 packet_disconnect("fork failed: %.100s", strerror(errno));
478 /* Set interactive/non-interactive mode. */
479 packet_set_interactive(s->display != NULL);
481 /* We are the parent. Close the child sides of the pipes. */
487 if (s->is_subsystem) {
491 session_set_fds(s, pin[1], pout[0], perr[0]);
493 /* Enter the interactive session. */
494 server_loop(pid, pin[1], pout[0], perr[0]);
495 /* server_loop has closed pin[1], pout[0], and perr[0]. */
497 #else /* USE_PIPES */
498 /* We are the parent. Close the child sides of the socket pairs. */
503 * Clear loginmsg, since it's the child's responsibility to display
504 * it to the user, otherwise multiple sessions may accumulate
505 * multiple copies of the login messages.
507 buffer_clear(&loginmsg);
510 * Enter the interactive session. Note: server_loop must be able to
511 * handle the case that fdin and fdout are the same.
514 session_set_fds(s, inout[1], inout[1], s->is_subsystem ? -1 : err[1]);
516 server_loop(pid, inout[1], inout[1], err[1]);
517 /* server_loop has closed inout[1] and err[1]. */
519 #endif /* USE_PIPES */
523 * This is called to fork and execute a command when we have a tty. This
524 * will call do_child from the child, and server_loop from the parent after
525 * setting up file descriptors, controlling tty, updating wtmp, utmp,
526 * lastlog, and other such operations.
529 do_exec_pty(Session *s, const char *command)
531 int fdout, ptyfd, ttyfd, ptymaster;
535 fatal("do_exec_pty: no session");
540 if (options.use_pam) {
541 do_pam_set_tty(s->tty);
547 /* Fork the child. */
548 if ((pid = fork()) == 0) {
551 /* Child. Reinitialize the log because the pid has changed. */
552 log_init(__progname, options.log_level, options.log_facility, log_stderr);
553 /* Close the master side of the pseudo tty. */
556 /* Make the pseudo tty our controlling tty. */
557 pty_make_controlling_tty(&ttyfd, s->tty);
559 /* Redirect stdin/stdout/stderr from the pseudo tty. */
560 if (dup2(ttyfd, 0) < 0)
561 error("dup2 stdin: %s", strerror(errno));
562 if (dup2(ttyfd, 1) < 0)
563 error("dup2 stdout: %s", strerror(errno));
564 if (dup2(ttyfd, 2) < 0)
565 error("dup2 stderr: %s", strerror(errno));
567 /* Close the extra descriptor for the pseudo tty. */
570 /* record login, etc. similar to login(1) */
572 if (!(options.use_login && command == NULL)) {
574 cray_init_job(s->pw); /* set up cray jid and tmpdir */
576 do_login(s, command);
578 # ifdef LOGIN_NEEDS_UTMPX
584 /* Do common processing for the child, such as execing the command. */
585 do_child(s, command);
589 signal(WJSIGNAL, cray_job_termination_handler);
593 cygwin_set_impersonation_token(INVALID_HANDLE_VALUE);
596 packet_disconnect("fork failed: %.100s", strerror(errno));
599 /* Parent. Close the slave side of the pseudo tty. */
603 * Create another descriptor of the pty master side for use as the
604 * standard input. We could use the original descriptor, but this
605 * simplifies code in server_loop. The descriptor is bidirectional.
609 packet_disconnect("dup #1 failed: %.100s", strerror(errno));
611 /* we keep a reference to the pty master */
612 ptymaster = dup(ptyfd);
614 packet_disconnect("dup #2 failed: %.100s", strerror(errno));
615 s->ptymaster = ptymaster;
617 /* Enter interactive session. */
618 packet_set_interactive(1);
620 session_set_fds(s, ptyfd, fdout, -1);
622 server_loop(pid, ptyfd, fdout, -1);
623 /* server_loop _has_ closed ptyfd and fdout. */
627 #ifdef LOGIN_NEEDS_UTMPX
629 do_pre_login(Session *s)
632 struct sockaddr_storage from;
633 pid_t pid = getpid();
636 * Get IP address of client. If the connection is not a socket, let
637 * the address be 0.0.0.0.
639 memset(&from, 0, sizeof(from));
640 fromlen = sizeof(from);
641 if (packet_connection_is_on_socket()) {
642 if (getpeername(packet_get_connection_in(),
643 (struct sockaddr *) & from, &fromlen) < 0) {
644 debug("getpeername: %.100s", strerror(errno));
649 record_utmp_only(pid, s->tty, s->pw->pw_name,
650 get_remote_name_or_ip(utmp_len, options.use_dns),
651 (struct sockaddr *)&from, fromlen);
656 * This is called to fork and execute a command. If another command is
657 * to be forced, execute that instead.
660 do_exec(Session *s, const char *command)
662 if (forced_command) {
663 original_command = command;
664 command = forced_command;
665 debug("Forced command '%.900s'", command);
670 PRIVSEP(audit_run_command(command));
671 else if (s->ttyfd == -1) {
672 char *shell = s->pw->pw_shell;
674 if (shell[0] == '\0') /* empty shell means /bin/sh */
676 PRIVSEP(audit_run_command(shell));
681 if (options.gss_authentication) {
682 temporarily_use_uid(s->pw);
683 ssh_gssapi_storecreds();
689 do_exec_pty(s, command);
691 do_exec_no_pty(s, command);
693 original_command = NULL;
696 * Clear loginmsg: it's the child's responsibility to display
697 * it to the user, otherwise multiple sessions may accumulate
698 * multiple copies of the login messages.
700 buffer_clear(&loginmsg);
703 /* administrative, login(1)-like work */
705 do_login(Session *s, const char *command)
708 struct sockaddr_storage from;
709 struct passwd * pw = s->pw;
710 pid_t pid = getpid();
713 * Get IP address of client. If the connection is not a socket, let
714 * the address be 0.0.0.0.
716 memset(&from, 0, sizeof(from));
717 fromlen = sizeof(from);
718 if (packet_connection_is_on_socket()) {
719 if (getpeername(packet_get_connection_in(),
720 (struct sockaddr *) & from, &fromlen) < 0) {
721 debug("getpeername: %.100s", strerror(errno));
726 /* Record that there was a login on that tty from the remote host. */
728 record_login(pid, s->tty, pw->pw_name, pw->pw_uid,
729 get_remote_name_or_ip(utmp_len,
731 (struct sockaddr *)&from, fromlen);
735 * If password change is needed, do it now.
736 * This needs to occur before the ~/.hushlogin check.
738 if (options.use_pam && !use_privsep && s->authctxt->force_pwchange) {
741 s->authctxt->force_pwchange = 0;
742 /* XXX - signal [net] parent to enable forwardings */
746 if (check_quietlogin(s, command))
755 * Display the message of the day.
763 if (options.print_motd) {
764 #ifdef HAVE_LOGIN_CAP
765 f = fopen(login_getcapstr(lc, "welcome", "/etc/motd",
768 f = fopen("/etc/motd", "r");
771 while (fgets(buf, sizeof(buf), f))
780 * Check for quiet login, either .hushlogin or command given.
783 check_quietlogin(Session *s, const char *command)
786 struct passwd *pw = s->pw;
789 /* Return 1 if .hushlogin exists or a command given. */
792 snprintf(buf, sizeof(buf), "%.200s/.hushlogin", pw->pw_dir);
793 #ifdef HAVE_LOGIN_CAP
794 if (login_getcapbool(lc, "hushlogin", 0) || stat(buf, &st) >= 0)
797 if (stat(buf, &st) >= 0)
804 * Sets the value of the given variable in the environment. If the variable
805 * already exists, its value is overriden.
808 child_set_env(char ***envp, u_int *envsizep, const char *name,
816 * If we're passed an uninitialized list, allocate a single null
817 * entry before continuing.
819 if (*envp == NULL && *envsizep == 0) {
820 *envp = xmalloc(sizeof(char *));
826 * Find the slot where the value should be stored. If the variable
827 * already exists, we reuse the slot; otherwise we append a new slot
828 * at the end of the array, expanding if necessary.
831 namelen = strlen(name);
832 for (i = 0; env[i]; i++)
833 if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=')
836 /* Reuse the slot. */
839 /* New variable. Expand if necessary. */
841 if (i >= envsize - 1) {
843 fatal("child_set_env: too many env vars");
845 env = (*envp) = xrealloc(env, envsize * sizeof(char *));
848 /* Need to set the NULL pointer at end of array beyond the new slot. */
852 /* Allocate space and format the variable in the appropriate slot. */
853 env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1);
854 snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value);
858 * Reads environment variables from the given file and adds/overrides them
859 * into the environment. If the file does not exist, this does nothing.
860 * Otherwise, it must consist of empty lines, comments (line starts with '#')
861 * and assignments of the form name=value. No other forms are allowed.
864 read_environment_file(char ***env, u_int *envsize,
865 const char *filename)
872 f = fopen(filename, "r");
876 while (fgets(buf, sizeof(buf), f)) {
878 fatal("Too many lines in environment file %s", filename);
879 for (cp = buf; *cp == ' ' || *cp == '\t'; cp++)
881 if (!*cp || *cp == '#' || *cp == '\n')
883 if (strchr(cp, '\n'))
884 *strchr(cp, '\n') = '\0';
885 value = strchr(cp, '=');
887 fprintf(stderr, "Bad line %u in %.100s\n", lineno,
892 * Replace the equals sign by nul, and advance value to
897 child_set_env(env, envsize, cp, value);
902 #ifdef HAVE_ETC_DEFAULT_LOGIN
904 * Return named variable from specified environment, or NULL if not present.
907 child_get_env(char **env, const char *name)
913 for (i=0; env[i] != NULL; i++)
914 if (strncmp(name, env[i], len) == 0 && env[i][len] == '=')
915 return(env[i] + len + 1);
920 * Read /etc/default/login.
921 * We pick up the PATH (or SUPATH for root) and UMASK.
924 read_etc_default_login(char ***env, u_int *envsize, uid_t uid)
926 char **tmpenv = NULL, *var;
927 u_int i, tmpenvsize = 0;
931 * We don't want to copy the whole file to the child's environment,
932 * so we use a temporary environment and copy the variables we're
935 read_environment_file(&tmpenv, &tmpenvsize, "/etc/default/login");
941 var = child_get_env(tmpenv, "SUPATH");
943 var = child_get_env(tmpenv, "PATH");
945 child_set_env(env, envsize, "PATH", var);
947 if ((var = child_get_env(tmpenv, "UMASK")) != NULL)
948 if (sscanf(var, "%5lo", &mask) == 1)
951 for (i = 0; tmpenv[i] != NULL; i++)
955 #endif /* HAVE_ETC_DEFAULT_LOGIN */
957 void copy_environment(char **source, char ***env, u_int *envsize)
959 char *var_name, *var_val;
965 for(i = 0; source[i] != NULL; i++) {
966 var_name = xstrdup(source[i]);
967 if ((var_val = strstr(var_name, "=")) == NULL) {
973 debug3("Copy environment: %s=%s", var_name, var_val);
974 child_set_env(env, envsize, var_name, var_val);
981 do_setup_env(Session *s, const char *shell)
985 char **env, *laddr, *path = NULL;
986 struct passwd *pw = s->pw;
988 /* Initialize the environment. */
990 env = xmalloc(envsize * sizeof(char *));
995 * The Windows environment contains some setting which are
996 * important for a running system. They must not be dropped.
1001 p = fetch_windows_environment();
1002 copy_environment(p, &env, &envsize);
1003 free_windows_environment(p);
1008 /* Allow any GSSAPI methods that we've used to alter
1009 * the childs environment as they see fit
1011 ssh_gssapi_do_child(&env, &envsize);
1014 if (!options.use_login) {
1015 /* Set basic environment. */
1016 for (i = 0; i < s->num_env; i++)
1017 child_set_env(&env, &envsize, s->env[i].name,
1020 child_set_env(&env, &envsize, "USER", pw->pw_name);
1021 child_set_env(&env, &envsize, "LOGNAME", pw->pw_name);
1023 child_set_env(&env, &envsize, "LOGIN", pw->pw_name);
1025 child_set_env(&env, &envsize, "HOME", pw->pw_dir);
1026 #ifdef HAVE_LOGIN_CAP
1027 if (setusercontext(lc, pw, pw->pw_uid, LOGIN_SETPATH) < 0)
1028 child_set_env(&env, &envsize, "PATH", _PATH_STDPATH);
1030 child_set_env(&env, &envsize, "PATH", getenv("PATH"));
1031 #else /* HAVE_LOGIN_CAP */
1032 # ifndef HAVE_CYGWIN
1034 * There's no standard path on Windows. The path contains
1035 * important components pointing to the system directories,
1036 * needed for loading shared libraries. So the path better
1037 * remains intact here.
1039 # ifdef HAVE_ETC_DEFAULT_LOGIN
1040 read_etc_default_login(&env, &envsize, pw->pw_uid);
1041 path = child_get_env(env, "PATH");
1042 # endif /* HAVE_ETC_DEFAULT_LOGIN */
1043 if (path == NULL || *path == '\0') {
1044 child_set_env(&env, &envsize, "PATH",
1045 s->pw->pw_uid == 0 ?
1046 SUPERUSER_PATH : _PATH_STDPATH);
1048 # endif /* HAVE_CYGWIN */
1049 #endif /* HAVE_LOGIN_CAP */
1051 snprintf(buf, sizeof buf, "%.200s/%.50s",
1052 _PATH_MAILDIR, pw->pw_name);
1053 child_set_env(&env, &envsize, "MAIL", buf);
1055 /* Normal systems set SHELL by default. */
1056 child_set_env(&env, &envsize, "SHELL", shell);
1059 child_set_env(&env, &envsize, "TZ", getenv("TZ"));
1061 /* Set custom environment options from RSA authentication. */
1062 if (!options.use_login) {
1063 while (custom_environment) {
1064 struct envstring *ce = custom_environment;
1067 for (i = 0; str[i] != '=' && str[i]; i++)
1069 if (str[i] == '=') {
1071 child_set_env(&env, &envsize, str, str + i + 1);
1073 custom_environment = ce->next;
1079 /* SSH_CLIENT deprecated */
1080 snprintf(buf, sizeof buf, "%.50s %d %d",
1081 get_remote_ipaddr(), get_remote_port(), get_local_port());
1082 child_set_env(&env, &envsize, "SSH_CLIENT", buf);
1084 laddr = get_local_ipaddr(packet_get_connection_in());
1085 snprintf(buf, sizeof buf, "%.50s %d %.50s %d",
1086 get_remote_ipaddr(), get_remote_port(), laddr, get_local_port());
1088 child_set_env(&env, &envsize, "SSH_CONNECTION", buf);
1091 child_set_env(&env, &envsize, "SSH_TTY", s->tty);
1093 child_set_env(&env, &envsize, "TERM", s->term);
1095 child_set_env(&env, &envsize, "DISPLAY", s->display);
1096 if (original_command)
1097 child_set_env(&env, &envsize, "SSH_ORIGINAL_COMMAND",
1101 if (cray_tmpdir[0] != '\0')
1102 child_set_env(&env, &envsize, "TMPDIR", cray_tmpdir);
1103 #endif /* _UNICOS */
1106 * Since we clear KRB5CCNAME at startup, if it's set now then it
1107 * must have been set by a native authentication method (eg AIX or
1108 * SIA), so copy it to the child.
1113 if ((cp = getenv("KRB5CCNAME")) != NULL)
1114 child_set_env(&env, &envsize, "KRB5CCNAME", cp);
1121 if ((cp = getenv("AUTHSTATE")) != NULL)
1122 child_set_env(&env, &envsize, "AUTHSTATE", cp);
1123 read_environment_file(&env, &envsize, "/etc/environment");
1127 if (s->authctxt->krb5_ccname)
1128 child_set_env(&env, &envsize, "KRB5CCNAME",
1129 s->authctxt->krb5_ccname);
1133 * Pull in any environment variables that may have
1136 if (options.use_pam) {
1139 p = fetch_pam_child_environment();
1140 copy_environment(p, &env, &envsize);
1141 free_pam_environment(p);
1143 p = fetch_pam_environment();
1144 copy_environment(p, &env, &envsize);
1145 free_pam_environment(p);
1147 #endif /* USE_PAM */
1149 if (auth_sock_name != NULL)
1150 child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME,
1153 /* read $HOME/.ssh/environment. */
1154 if (options.permit_user_env && !options.use_login) {
1155 snprintf(buf, sizeof buf, "%.200s/.ssh/environment",
1156 strcmp(pw->pw_dir, "/") ? pw->pw_dir : "");
1157 read_environment_file(&env, &envsize, buf);
1160 /* dump the environment */
1161 fprintf(stderr, "Environment:\n");
1162 for (i = 0; env[i]; i++)
1163 fprintf(stderr, " %.200s\n", env[i]);
1169 * Run $HOME/.ssh/rc, /etc/ssh/sshrc, or xauth (whichever is found
1170 * first in this order).
1173 do_rc_files(Session *s, const char *shell)
1181 s->display != NULL && s->auth_proto != NULL && s->auth_data != NULL;
1183 /* ignore _PATH_SSH_USER_RC for subsystems */
1184 if (!s->is_subsystem && (stat(_PATH_SSH_USER_RC, &st) >= 0)) {
1185 snprintf(cmd, sizeof cmd, "%s -c '%s %s'",
1186 shell, _PATH_BSHELL, _PATH_SSH_USER_RC);
1188 fprintf(stderr, "Running %s\n", cmd);
1189 f = popen(cmd, "w");
1192 fprintf(f, "%s %s\n", s->auth_proto,
1196 fprintf(stderr, "Could not run %s\n",
1198 } else if (stat(_PATH_SSH_SYSTEM_RC, &st) >= 0) {
1200 fprintf(stderr, "Running %s %s\n", _PATH_BSHELL,
1201 _PATH_SSH_SYSTEM_RC);
1202 f = popen(_PATH_BSHELL " " _PATH_SSH_SYSTEM_RC, "w");
1205 fprintf(f, "%s %s\n", s->auth_proto,
1209 fprintf(stderr, "Could not run %s\n",
1210 _PATH_SSH_SYSTEM_RC);
1211 } else if (do_xauth && options.xauth_location != NULL) {
1212 /* Add authority data to .Xauthority if appropriate. */
1215 "Running %.500s remove %.100s\n",
1216 options.xauth_location, s->auth_display);
1218 "%.500s add %.100s %.100s %.100s\n",
1219 options.xauth_location, s->auth_display,
1220 s->auth_proto, s->auth_data);
1222 snprintf(cmd, sizeof cmd, "%s -q -",
1223 options.xauth_location);
1224 f = popen(cmd, "w");
1226 fprintf(f, "remove %s\n",
1228 fprintf(f, "add %s %s %s\n",
1229 s->auth_display, s->auth_proto,
1233 fprintf(stderr, "Could not run %s\n",
1240 do_nologin(struct passwd *pw)
1245 #ifdef HAVE_LOGIN_CAP
1246 if (!login_getcapbool(lc, "ignorenologin", 0) && pw->pw_uid)
1247 f = fopen(login_getcapstr(lc, "nologin", _PATH_NOLOGIN,
1248 _PATH_NOLOGIN), "r");
1251 f = fopen(_PATH_NOLOGIN, "r");
1254 /* /etc/nologin exists. Print its contents and exit. */
1255 logit("User %.100s not allowed because %s exists",
1256 pw->pw_name, _PATH_NOLOGIN);
1257 while (fgets(buf, sizeof(buf), f))
1265 /* Set login name, uid, gid, and groups. */
1267 do_setusercontext(struct passwd *pw)
1270 if (getuid() == 0 || geteuid() == 0)
1271 #endif /* HAVE_CYGWIN */
1274 #ifdef HAVE_SETPCRED
1275 if (setpcred(pw->pw_name, (char **)NULL) == -1)
1276 fatal("Failed to set process credentials");
1277 #endif /* HAVE_SETPCRED */
1278 #ifdef HAVE_LOGIN_CAP
1283 if (options.use_pam) {
1287 # endif /* USE_PAM */
1288 if (setusercontext(lc, pw, pw->pw_uid,
1289 (LOGIN_SETALL & ~LOGIN_SETPATH)) < 0) {
1290 perror("unable to set user context");
1294 # if defined(HAVE_GETLUID) && defined(HAVE_SETLUID)
1295 /* Sets login uid for accounting */
1296 if (getluid() == -1 && setluid(pw->pw_uid) == -1)
1297 error("setluid: %s", strerror(errno));
1298 # endif /* defined(HAVE_GETLUID) && defined(HAVE_SETLUID) */
1300 if (setlogin(pw->pw_name) < 0)
1301 error("setlogin failed: %s", strerror(errno));
1302 if (setgid(pw->pw_gid) < 0) {
1306 /* Initialize the group list. */
1307 if (initgroups(pw->pw_name, pw->pw_gid) < 0) {
1308 perror("initgroups");
1314 * PAM credentials may take the form of supplementary groups.
1315 * These will have been wiped by the above initgroups() call.
1316 * Reestablish them here.
1318 if (options.use_pam) {
1322 # endif /* USE_PAM */
1323 # if defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY)
1324 irix_setusercontext(pw);
1325 # endif /* defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) */
1329 /* Permanently switch to the desired uid. */
1330 permanently_set_uid(pw);
1337 if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid)
1338 fatal("Failed to set uids to %u.", (u_int) pw->pw_uid);
1342 do_pwchange(Session *s)
1345 fprintf(stderr, "WARNING: Your password has expired.\n");
1346 if (s->ttyfd != -1) {
1348 "You must change your password now and login again!\n");
1349 execl(_PATH_PASSWD_PROG, "passwd", (char *)NULL);
1353 "Password change required but no TTY available.\n");
1359 launch_login(struct passwd *pw, const char *hostname)
1361 /* Launch login(1). */
1363 execl(LOGIN_PROGRAM, "login", "-h", hostname,
1364 #ifdef xxxLOGIN_NEEDS_TERM
1365 (s->term ? s->term : "unknown"),
1366 #endif /* LOGIN_NEEDS_TERM */
1367 #ifdef LOGIN_NO_ENDOPT
1368 "-p", "-f", pw->pw_name, (char *)NULL);
1370 "-p", "-f", "--", pw->pw_name, (char *)NULL);
1373 /* Login couldn't be executed, die. */
1380 child_close_fds(void)
1384 if (packet_get_connection_in() == packet_get_connection_out())
1385 close(packet_get_connection_in());
1387 close(packet_get_connection_in());
1388 close(packet_get_connection_out());
1391 * Close all descriptors related to channels. They will still remain
1392 * open in the parent.
1394 /* XXX better use close-on-exec? -markus */
1395 channel_close_all();
1398 * Close any extra file descriptors. Note that there may still be
1399 * descriptors left by system functions. They will be closed later.
1404 * Close any extra open file descriptors so that we don\'t have them
1405 * hanging around in clients. Note that we want to do this after
1406 * initgroups, because at least on Solaris 2.3 it leaves file
1409 for (i = 3; i < 64; i++)
1414 * Performs common processing for the child, such as setting up the
1415 * environment, closing extra file descriptors, setting the user and group
1416 * ids, and executing the command or shell.
1419 do_child(Session *s, const char *command)
1421 extern char **environ;
1424 const char *shell, *shell0, *hostname = NULL;
1425 struct passwd *pw = s->pw;
1427 /* remove hostkey from the child's memory */
1428 destroy_sensitive_data();
1430 /* Force a password change */
1431 if (s->authctxt->force_pwchange) {
1432 do_setusercontext(pw);
1438 /* login(1) is only called if we execute the login shell */
1439 if (options.use_login && command != NULL)
1440 options.use_login = 0;
1443 cray_setup(pw->pw_uid, pw->pw_name, command);
1444 #endif /* _UNICOS */
1447 * Login(1) does this as well, and it needs uid 0 for the "-h"
1448 * switch, so we let login(1) to this for us.
1450 if (!options.use_login) {
1452 session_setup_sia(pw, s->ttyfd == -1 ? NULL : s->tty);
1453 if (!check_quietlogin(s, command))
1455 #else /* HAVE_OSF_SIA */
1457 do_setusercontext(pw);
1459 * PAM session modules in do_setusercontext may have
1460 * generated messages, so if this in an interactive
1461 * login then display them too.
1463 if (!check_quietlogin(s, command))
1465 #endif /* HAVE_OSF_SIA */
1469 if (options.use_pam && !is_pam_session_open()) {
1476 * Get the shell from the password data. An empty shell field is
1477 * legal, and means /bin/sh.
1479 shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
1482 * Make sure $SHELL points to the shell from the password file,
1483 * even if shell is overridden from login.conf
1485 env = do_setup_env(s, shell);
1487 #ifdef HAVE_LOGIN_CAP
1488 shell = login_getcapstr(lc, "shell", (char *)shell, (char *)shell);
1491 /* we have to stash the hostname before we close our socket. */
1492 if (options.use_login)
1493 hostname = get_remote_name_or_ip(utmp_len,
1496 * Close the connection descriptors; note that this is the child, and
1497 * the server will still have the socket open, and it is important
1498 * that we do not shutdown it. Note that the descriptors cannot be
1499 * closed before building the environment, as we call
1500 * get_remote_ipaddr there.
1505 * Must take new environment into use so that .ssh/rc,
1506 * /etc/ssh/sshrc and xauth are run in the proper environment.
1510 #if defined(KRB5) && defined(USE_AFS)
1512 * At this point, we check to see if AFS is active and if we have
1513 * a valid Kerberos 5 TGT. If so, it seems like a good idea to see
1514 * if we can (and need to) extend the ticket into an AFS token. If
1515 * we don't do this, we run into potential problems if the user's
1516 * home directory is in AFS and it's not world-readable.
1519 if (options.kerberos_get_afs_token && k_hasafs() &&
1520 (s->authctxt->krb5_ctx != NULL)) {
1523 debug("Getting AFS token");
1527 if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0)
1528 krb5_afslog(s->authctxt->krb5_ctx,
1529 s->authctxt->krb5_fwd_ccache, cell, NULL);
1531 krb5_afslog_home(s->authctxt->krb5_ctx,
1532 s->authctxt->krb5_fwd_ccache, NULL, NULL, pw->pw_dir);
1536 /* Change current directory to the user\'s home directory. */
1537 if (chdir(pw->pw_dir) < 0) {
1538 fprintf(stderr, "Could not chdir to home directory %s: %s\n",
1539 pw->pw_dir, strerror(errno));
1540 #ifdef HAVE_LOGIN_CAP
1541 if (login_getcapbool(lc, "requirehome", 0))
1546 if (!options.use_login)
1547 do_rc_files(s, shell);
1549 /* restore SIGPIPE for child */
1550 signal(SIGPIPE, SIG_DFL);
1552 if (options.use_login) {
1553 launch_login(pw, hostname);
1557 /* Get the last component of the shell name. */
1558 if ((shell0 = strrchr(shell, '/')) != NULL)
1564 * If we have no command, execute the shell. In this case, the shell
1565 * name to be passed in argv[0] is preceded by '-' to indicate that
1566 * this is a login shell.
1571 /* Start the shell. Set initial character to '-'. */
1574 if (strlcpy(argv0 + 1, shell0, sizeof(argv0) - 1)
1575 >= sizeof(argv0) - 1) {
1581 /* Execute the shell. */
1584 execve(shell, argv, env);
1586 /* Executing the shell failed. */
1591 * Execute the command using the user's shell. This uses the -c
1592 * option to execute the command.
1594 argv[0] = (char *) shell0;
1596 argv[2] = (char *) command;
1598 execve(shell, argv, env);
1607 static int did_init = 0;
1609 debug("session_new: init");
1610 for (i = 0; i < MAX_SESSIONS; i++) {
1611 sessions[i].used = 0;
1615 for (i = 0; i < MAX_SESSIONS; i++) {
1616 Session *s = &sessions[i];
1618 memset(s, 0, sizeof(*s));
1624 debug("session_new: session %d", i);
1635 for (i = 0; i < MAX_SESSIONS; i++) {
1636 Session *s = &sessions[i];
1637 debug("dump: used %d session %d %p channel %d pid %ld",
1647 session_open(Authctxt *authctxt, int chanid)
1649 Session *s = session_new();
1650 debug("session_open: channel %d", chanid);
1652 error("no more sessions");
1655 s->authctxt = authctxt;
1656 s->pw = authctxt->pw;
1657 if (s->pw == NULL || !authctxt->valid)
1658 fatal("no user for session %d", s->self);
1659 debug("session_open: session %d: link with channel %d", s->self, chanid);
1665 session_by_tty(char *tty)
1668 for (i = 0; i < MAX_SESSIONS; i++) {
1669 Session *s = &sessions[i];
1670 if (s->used && s->ttyfd != -1 && strcmp(s->tty, tty) == 0) {
1671 debug("session_by_tty: session %d tty %s", i, tty);
1675 debug("session_by_tty: unknown tty %.100s", tty);
1681 session_by_channel(int id)
1684 for (i = 0; i < MAX_SESSIONS; i++) {
1685 Session *s = &sessions[i];
1686 if (s->used && s->chanid == id) {
1687 debug("session_by_channel: session %d channel %d", i, id);
1691 debug("session_by_channel: unknown channel %d", id);
1697 session_by_pid(pid_t pid)
1700 debug("session_by_pid: pid %ld", (long)pid);
1701 for (i = 0; i < MAX_SESSIONS; i++) {
1702 Session *s = &sessions[i];
1703 if (s->used && s->pid == pid)
1706 error("session_by_pid: unknown pid %ld", (long)pid);
1712 session_window_change_req(Session *s)
1714 s->col = packet_get_int();
1715 s->row = packet_get_int();
1716 s->xpixel = packet_get_int();
1717 s->ypixel = packet_get_int();
1719 pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1724 session_pty_req(Session *s)
1730 debug("Allocating a pty not permitted for this authentication.");
1733 if (s->ttyfd != -1) {
1734 packet_disconnect("Protocol error: you already have a pty.");
1738 s->term = packet_get_string(&len);
1741 s->col = packet_get_int();
1742 s->row = packet_get_int();
1744 s->row = packet_get_int();
1745 s->col = packet_get_int();
1747 s->xpixel = packet_get_int();
1748 s->ypixel = packet_get_int();
1750 if (strcmp(s->term, "") == 0) {
1755 /* Allocate a pty and open it. */
1756 debug("Allocating pty.");
1757 if (!PRIVSEP(pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty)))) {
1763 error("session_pty_req: session %d alloc failed", s->self);
1766 debug("session_pty_req: session %d alloc %s", s->self, s->tty);
1768 /* for SSH1 the tty modes length is not given */
1770 n_bytes = packet_remaining();
1771 tty_parse_modes(s->ttyfd, &n_bytes);
1774 pty_setowner(s->pw, s->tty);
1776 /* Set window size from the packet. */
1777 pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1780 session_proctitle(s);
1785 session_subsystem_req(Session *s)
1790 char *cmd, *subsys = packet_get_string(&len);
1794 logit("subsystem request for %.100s", subsys);
1796 for (i = 0; i < options.num_subsystems; i++) {
1797 if (strcmp(subsys, options.subsystem_name[i]) == 0) {
1798 cmd = options.subsystem_command[i];
1799 if (stat(cmd, &st) < 0) {
1800 error("subsystem: cannot stat %s: %s", cmd,
1804 debug("subsystem: exec() %s", cmd);
1805 s->is_subsystem = 1;
1813 logit("subsystem request for %.100s failed, subsystem not found",
1821 session_x11_req(Session *s)
1825 s->single_connection = packet_get_char();
1826 s->auth_proto = packet_get_string(NULL);
1827 s->auth_data = packet_get_string(NULL);
1828 s->screen = packet_get_int();
1831 success = session_setup_x11fwd(s);
1833 xfree(s->auth_proto);
1834 xfree(s->auth_data);
1835 s->auth_proto = NULL;
1836 s->auth_data = NULL;
1842 session_shell_req(Session *s)
1850 session_exec_req(Session *s)
1853 char *command = packet_get_string(&len);
1855 do_exec(s, command);
1861 session_break_req(Session *s)
1864 packet_get_int(); /* ignored */
1867 if (s->ttyfd == -1 ||
1868 tcsendbreak(s->ttyfd, 0) < 0)
1874 session_env_req(Session *s)
1877 u_int name_len, val_len, i;
1879 name = packet_get_string(&name_len);
1880 val = packet_get_string(&val_len);
1883 /* Don't set too many environment variables */
1884 if (s->num_env > 128) {
1885 debug2("Ignoring env request %s: too many env vars", name);
1889 for (i = 0; i < options.num_accept_env; i++) {
1890 if (match_pattern(name, options.accept_env[i])) {
1891 debug2("Setting env %d: %s=%s", s->num_env, name, val);
1892 s->env = xrealloc(s->env, sizeof(*s->env) *
1894 s->env[s->num_env].name = name;
1895 s->env[s->num_env].val = val;
1900 debug2("Ignoring env request %s: disallowed name", name);
1909 session_auth_agent_req(Session *s)
1911 static int called = 0;
1913 if (no_agent_forwarding_flag) {
1914 debug("session_auth_agent_req: no_agent_forwarding_flag");
1921 return auth_input_request_forwarding(s->pw);
1926 session_input_channel_req(Channel *c, const char *rtype)
1931 if ((s = session_by_channel(c->self)) == NULL) {
1932 logit("session_input_channel_req: no session %d req %.100s",
1936 debug("session_input_channel_req: session %d req %s", s->self, rtype);
1939 * a session is in LARVAL state until a shell, a command
1940 * or a subsystem is executed
1942 if (c->type == SSH_CHANNEL_LARVAL) {
1943 if (strcmp(rtype, "shell") == 0) {
1944 success = session_shell_req(s);
1945 } else if (strcmp(rtype, "exec") == 0) {
1946 success = session_exec_req(s);
1947 } else if (strcmp(rtype, "pty-req") == 0) {
1948 success = session_pty_req(s);
1949 } else if (strcmp(rtype, "x11-req") == 0) {
1950 success = session_x11_req(s);
1951 } else if (strcmp(rtype, "auth-agent-req@openssh.com") == 0) {
1952 success = session_auth_agent_req(s);
1953 } else if (strcmp(rtype, "subsystem") == 0) {
1954 success = session_subsystem_req(s);
1955 } else if (strcmp(rtype, "env") == 0) {
1956 success = session_env_req(s);
1959 if (strcmp(rtype, "window-change") == 0) {
1960 success = session_window_change_req(s);
1961 } else if (strcmp(rtype, "break") == 0) {
1962 success = session_break_req(s);
1969 session_set_fds(Session *s, int fdin, int fdout, int fderr)
1972 fatal("session_set_fds: called for proto != 2.0");
1974 * now that have a child and a pipe to the child,
1975 * we can activate our channel and register the fd's
1977 if (s->chanid == -1)
1978 fatal("no channel for session %d", s->self);
1979 channel_set_fds(s->chanid,
1981 fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ,
1983 CHAN_SES_WINDOW_DEFAULT);
1987 * Function to perform pty cleanup. Also called if we get aborted abnormally
1988 * (e.g., due to a dropped connection).
1991 session_pty_cleanup2(Session *s)
1994 error("session_pty_cleanup: no session");
2000 debug("session_pty_cleanup: session %d release %s", s->self, s->tty);
2002 /* Record that the user has logged out. */
2004 record_logout(s->pid, s->tty, s->pw->pw_name);
2006 /* Release the pseudo-tty. */
2008 pty_release(s->tty);
2011 * Close the server side of the socket pairs. We must do this after
2012 * the pty cleanup, so that another process doesn't get this pty
2013 * while we're still cleaning up.
2015 if (close(s->ptymaster) < 0)
2016 error("close(s->ptymaster/%d): %s", s->ptymaster, strerror(errno));
2018 /* unlink pty from session */
2023 session_pty_cleanup(Session *s)
2025 PRIVSEP(session_pty_cleanup2(s));
2031 #define SSH_SIG(x) if (sig == SIG ## x) return #x
2046 return "SIG@openssh.com";
2050 session_exit_message(Session *s, int status)
2054 if ((c = channel_lookup(s->chanid)) == NULL)
2055 fatal("session_exit_message: session %d: no channel %d",
2056 s->self, s->chanid);
2057 debug("session_exit_message: session %d channel %d pid %ld",
2058 s->self, s->chanid, (long)s->pid);
2060 if (WIFEXITED(status)) {
2061 channel_request_start(s->chanid, "exit-status", 0);
2062 packet_put_int(WEXITSTATUS(status));
2064 } else if (WIFSIGNALED(status)) {
2065 channel_request_start(s->chanid, "exit-signal", 0);
2066 packet_put_cstring(sig2name(WTERMSIG(status)));
2068 packet_put_char(WCOREDUMP(status));
2069 #else /* WCOREDUMP */
2071 #endif /* WCOREDUMP */
2072 packet_put_cstring("");
2073 packet_put_cstring("");
2076 /* Some weird exit cause. Just exit. */
2077 packet_disconnect("wait returned status %04x.", status);
2080 /* disconnect channel */
2081 debug("session_exit_message: release channel %d", s->chanid);
2082 channel_cancel_cleanup(s->chanid);
2084 * emulate a write failure with 'chan_write_failed', nobody will be
2085 * interested in data we write.
2086 * Note that we must not call 'chan_read_failed', since there could
2087 * be some more data waiting in the pipe.
2089 if (c->ostate != CHAN_OUTPUT_CLOSED)
2090 chan_write_failed(c);
2095 session_close(Session *s)
2099 debug("session_close: session %d pid %ld", s->self, (long)s->pid);
2101 session_pty_cleanup(s);
2106 if (s->auth_display)
2107 xfree(s->auth_display);
2109 xfree(s->auth_data);
2111 xfree(s->auth_proto);
2113 for (i = 0; i < s->num_env; i++) {
2114 xfree(s->env[i].name);
2115 xfree(s->env[i].val);
2119 session_proctitle(s);
2123 session_close_by_pid(pid_t pid, int status)
2125 Session *s = session_by_pid(pid);
2127 debug("session_close_by_pid: no session for pid %ld",
2131 if (s->chanid != -1)
2132 session_exit_message(s, status);
2137 * this is called when a channel dies before
2138 * the session 'child' itself dies
2141 session_close_by_channel(int id, void *arg)
2143 Session *s = session_by_channel(id);
2145 debug("session_close_by_channel: no session for id %d", id);
2148 debug("session_close_by_channel: channel %d child %ld",
2151 debug("session_close_by_channel: channel %d: has child", id);
2153 * delay detach of session, but release pty, since
2154 * the fd's to the child are already closed
2157 session_pty_cleanup(s);
2160 /* detach by removing callback */
2161 channel_cancel_cleanup(s->chanid);
2167 session_destroy_all(void (*closefunc)(Session *))
2170 for (i = 0; i < MAX_SESSIONS; i++) {
2171 Session *s = &sessions[i];
2173 if (closefunc != NULL)
2182 session_tty_list(void)
2184 static char buf[1024];
2189 for (i = 0; i < MAX_SESSIONS; i++) {
2190 Session *s = &sessions[i];
2191 if (s->used && s->ttyfd != -1) {
2193 if (strncmp(s->tty, "/dev/", 5) != 0) {
2194 cp = strrchr(s->tty, '/');
2195 cp = (cp == NULL) ? s->tty : cp + 1;
2200 strlcat(buf, ",", sizeof buf);
2201 strlcat(buf, cp, sizeof buf);
2205 strlcpy(buf, "notty", sizeof buf);
2210 session_proctitle(Session *s)
2213 error("no user for session %d", s->self);
2215 setproctitle("%s@%s", s->pw->pw_name, session_tty_list());
2219 session_setup_x11fwd(Session *s)
2222 char display[512], auth_display[512];
2223 char hostname[MAXHOSTNAMELEN];
2225 if (no_x11_forwarding_flag) {
2226 packet_send_debug("X11 forwarding disabled in user configuration file.");
2229 if (!options.x11_forwarding) {
2230 debug("X11 forwarding disabled in server configuration file.");
2233 if (!options.xauth_location ||
2234 (stat(options.xauth_location, &st) == -1)) {
2235 packet_send_debug("No xauth program; cannot forward with spoofing.");
2238 if (options.use_login) {
2239 packet_send_debug("X11 forwarding disabled; "
2240 "not compatible with UseLogin=yes.");
2243 if (s->display != NULL) {
2244 debug("X11 display already set.");
2247 if (x11_create_display_inet(options.x11_display_offset,
2248 options.x11_use_localhost, s->single_connection,
2249 &s->display_number) == -1) {
2250 debug("x11_create_display_inet failed.");
2254 /* Set up a suitable value for the DISPLAY variable. */
2255 if (gethostname(hostname, sizeof(hostname)) < 0)
2256 fatal("gethostname: %.100s", strerror(errno));
2258 * auth_display must be used as the displayname when the
2259 * authorization entry is added with xauth(1). This will be
2260 * different than the DISPLAY string for localhost displays.
2262 if (options.x11_use_localhost) {
2263 snprintf(display, sizeof display, "localhost:%u.%u",
2264 s->display_number, s->screen);
2265 snprintf(auth_display, sizeof auth_display, "unix:%u.%u",
2266 s->display_number, s->screen);
2267 s->display = xstrdup(display);
2268 s->auth_display = xstrdup(auth_display);
2270 #ifdef IPADDR_IN_DISPLAY
2272 struct in_addr my_addr;
2274 he = gethostbyname(hostname);
2276 error("Can't get IP address for X11 DISPLAY.");
2277 packet_send_debug("Can't get IP address for X11 DISPLAY.");
2280 memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr));
2281 snprintf(display, sizeof display, "%.50s:%u.%u", inet_ntoa(my_addr),
2282 s->display_number, s->screen);
2284 snprintf(display, sizeof display, "%.400s:%u.%u", hostname,
2285 s->display_number, s->screen);
2287 s->display = xstrdup(display);
2288 s->auth_display = xstrdup(display);
2295 do_authenticated2(Authctxt *authctxt)
2297 server_loop2(authctxt);
2301 do_cleanup(Authctxt *authctxt)
2303 static int called = 0;
2305 debug("do_cleanup");
2307 /* no cleanup if we're in the child for login shell */
2311 /* avoid double cleanup */
2316 if (authctxt == NULL)
2319 if (options.kerberos_ticket_cleanup &&
2321 krb5_cleanup_proc(authctxt);
2325 if (compat20 && options.gss_cleanup_creds)
2326 ssh_gssapi_cleanup_creds();
2330 if (options.use_pam) {
2332 sshpam_thread_cleanup();
2337 PRIVSEP(audit_event(CONNECTION_CLOSE));
2340 /* remove agent socket */
2341 auth_sock_cleanup_proc(authctxt->pw);
2344 * Cleanup ptys/utmp only if privsep is disabled,
2345 * or if running in monitor.
2347 if (!use_privsep || mm_is_monitor())
2348 session_destroy_all(session_pty_cleanup2);