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 $");
52 #include "auth-options.h"
53 #include "pathnames.h"
57 #include "serverloop.h"
60 #include "monitor_wrap.h"
62 #if defined(KRB5) && defined(USE_AFS)
72 Session *session_new(void);
73 void session_set_fds(Session *, int, int, int);
74 void session_pty_cleanup(Session *);
75 void session_proctitle(Session *);
76 int session_setup_x11fwd(Session *);
77 void do_exec_pty(Session *, const char *);
78 void do_exec_no_pty(Session *, const char *);
79 void do_exec(Session *, const char *);
80 void do_login(Session *, const char *);
81 #ifdef LOGIN_NEEDS_UTMPX
82 static void do_pre_login(Session *s);
84 void do_child(Session *, const char *);
86 int check_quietlogin(Session *, const char *);
88 static void do_authenticated1(Authctxt *);
89 static void do_authenticated2(Authctxt *);
91 static int session_pty_req(Session *);
94 extern ServerOptions options;
95 extern char *__progname;
96 extern int log_stderr;
97 extern int debug_flag;
98 extern u_int utmp_len;
99 extern int startup_pipe;
100 extern void destroy_sensitive_data(void);
101 extern Buffer loginmsg;
103 /* original command from peer. */
104 const char *original_command = NULL;
107 #define MAX_SESSIONS 10
108 Session sessions[MAX_SESSIONS];
110 #ifdef HAVE_LOGIN_CAP
114 static int is_child = 0;
116 /* Name and directory of socket for authentication agent forwarding. */
117 static char *auth_sock_name = NULL;
118 static char *auth_sock_dir = NULL;
120 /* removes the agent forwarding socket */
123 auth_sock_cleanup_proc(struct passwd *pw)
125 if (auth_sock_name != NULL) {
126 temporarily_use_uid(pw);
127 unlink(auth_sock_name);
128 rmdir(auth_sock_dir);
129 auth_sock_name = NULL;
135 auth_input_request_forwarding(struct passwd * pw)
139 struct sockaddr_un sunaddr;
141 if (auth_sock_name != NULL) {
142 error("authentication forwarding requested twice.");
146 /* Temporarily drop privileged uid for mkdir/bind. */
147 temporarily_use_uid(pw);
149 /* Allocate a buffer for the socket name, and format the name. */
150 auth_sock_name = xmalloc(MAXPATHLEN);
151 auth_sock_dir = xmalloc(MAXPATHLEN);
152 strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN);
154 /* Create private directory for socket */
155 if (mkdtemp(auth_sock_dir) == NULL) {
156 packet_send_debug("Agent forwarding disabled: "
157 "mkdtemp() failed: %.100s", strerror(errno));
159 xfree(auth_sock_name);
160 xfree(auth_sock_dir);
161 auth_sock_name = NULL;
162 auth_sock_dir = NULL;
165 snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%ld",
166 auth_sock_dir, (long) getpid());
168 /* Create the socket. */
169 sock = socket(AF_UNIX, SOCK_STREAM, 0);
171 packet_disconnect("socket: %.100s", strerror(errno));
173 /* Bind it to the name. */
174 memset(&sunaddr, 0, sizeof(sunaddr));
175 sunaddr.sun_family = AF_UNIX;
176 strlcpy(sunaddr.sun_path, auth_sock_name, sizeof(sunaddr.sun_path));
178 if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0)
179 packet_disconnect("bind: %.100s", strerror(errno));
181 /* Restore the privileged uid. */
184 /* Start listening on the socket. */
185 if (listen(sock, SSH_LISTEN_BACKLOG) < 0)
186 packet_disconnect("listen: %.100s", strerror(errno));
188 /* Allocate a channel for the authentication agent socket. */
189 nc = channel_new("auth socket",
190 SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1,
191 CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
192 0, "auth socket", 1);
193 strlcpy(nc->path, auth_sock_name, sizeof(nc->path));
198 display_loginmsg(void)
200 if (buffer_len(&loginmsg) > 0) {
201 buffer_append(&loginmsg, "\0", 1);
202 printf("%s", (char *)buffer_ptr(&loginmsg));
203 buffer_clear(&loginmsg);
208 do_authenticated(Authctxt *authctxt)
210 setproctitle("%s", authctxt->pw->pw_name);
213 * Cancel the alarm we set to limit the time taken for
217 if (startup_pipe != -1) {
221 /* setup the channel layer */
222 if (!no_port_forwarding_flag && options.allow_tcp_forwarding)
223 channel_permit_all_opens();
226 do_authenticated2(authctxt);
228 do_authenticated1(authctxt);
230 do_cleanup(authctxt);
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.
240 do_authenticated1(Authctxt *authctxt)
244 int success, type, screen_flag;
245 int enable_compression_after_reply = 0;
246 u_int proto_len, data_len, dlen, compression_level = 0;
250 error("no more sessions");
253 s->authctxt = authctxt;
254 s->pw = authctxt->pw;
257 * We stay in this loop until the client requests to execute a shell
263 /* Get a packet from the client. */
264 type = packet_read();
266 /* Process the packet. */
268 case SSH_CMSG_REQUEST_COMPRESSION:
269 compression_level = packet_get_int();
271 if (compression_level < 1 || compression_level > 9) {
272 packet_send_debug("Received invalid compression level %d.",
276 if (!options.compression) {
277 debug2("compression disabled");
280 /* Enable compression after we have responded with SUCCESS. */
281 enable_compression_after_reply = 1;
285 case SSH_CMSG_REQUEST_PTY:
286 success = session_pty_req(s);
289 case SSH_CMSG_X11_REQUEST_FORWARDING:
290 s->auth_proto = packet_get_string(&proto_len);
291 s->auth_data = packet_get_string(&data_len);
293 screen_flag = packet_get_protocol_flags() &
294 SSH_PROTOFLAG_SCREEN_NUMBER;
295 debug2("SSH_PROTOFLAG_SCREEN_NUMBER: %d", screen_flag);
297 if (packet_remaining() == 4) {
299 debug2("Buggy client: "
300 "X11 screen flag missing");
301 s->screen = packet_get_int();
306 success = session_setup_x11fwd(s);
308 xfree(s->auth_proto);
310 s->auth_proto = NULL;
315 case SSH_CMSG_AGENT_REQUEST_FORWARDING:
316 if (no_agent_forwarding_flag || compat13) {
317 debug("Authentication agent forwarding not permitted for this authentication.");
320 debug("Received authentication agent forwarding request.");
321 success = auth_input_request_forwarding(s->pw);
324 case SSH_CMSG_PORT_FORWARD_REQUEST:
325 if (no_port_forwarding_flag) {
326 debug("Port forwarding not permitted for this authentication.");
329 if (!options.allow_tcp_forwarding) {
330 debug("Port forwarding not permitted.");
333 debug("Received TCP/IP port forwarding request.");
334 channel_input_port_forward_request(s->pw->pw_uid == 0, options.gateway_ports);
338 case SSH_CMSG_MAX_PACKET_SIZE:
339 if (packet_set_maxsize(packet_get_int()) > 0)
343 case SSH_CMSG_EXEC_SHELL:
344 case SSH_CMSG_EXEC_CMD:
345 if (type == SSH_CMSG_EXEC_CMD) {
346 command = packet_get_string(&dlen);
347 debug("Exec command '%.500s'", command);
359 * Any unknown messages in this phase are ignored,
360 * and a failure message is returned.
362 logit("Unknown packet type received after authentication: %d", type);
364 packet_start(success ? SSH_SMSG_SUCCESS : SSH_SMSG_FAILURE);
368 /* Enable compression now that we have replied if appropriate. */
369 if (enable_compression_after_reply) {
370 enable_compression_after_reply = 0;
371 packet_start_compression(compression_level);
377 * This is called to fork and execute a command when we have no tty. This
378 * will call do_child from the child, and server_loop from the parent after
379 * setting up file descriptors and such.
382 do_exec_no_pty(Session *s, const char *command)
387 int pin[2], pout[2], perr[2];
388 /* Allocate pipes for communicating with the program. */
389 if (pipe(pin) < 0 || pipe(pout) < 0 || pipe(perr) < 0)
390 packet_disconnect("Could not create pipes: %.100s",
392 #else /* USE_PIPES */
393 int inout[2], err[2];
394 /* Uses socket pairs to communicate with the program. */
395 if (socketpair(AF_UNIX, SOCK_STREAM, 0, inout) < 0 ||
396 socketpair(AF_UNIX, SOCK_STREAM, 0, err) < 0)
397 packet_disconnect("Could not create socket pairs: %.100s",
399 #endif /* USE_PIPES */
401 fatal("do_exec_no_pty: no session");
403 session_proctitle(s);
406 if (options.use_pam && !use_privsep)
410 /* Fork the child. */
411 if ((pid = fork()) == 0) {
414 /* Child. Reinitialize the log since the pid has changed. */
415 log_init(__progname, options.log_level, options.log_facility, log_stderr);
418 * Create a new session and process group since the 4.4BSD
419 * setlogin() affects the entire process group.
422 error("setsid failed: %.100s", strerror(errno));
426 * Redirect stdin. We close the parent side of the socket
427 * pair, and make the child side the standard input.
430 if (dup2(pin[0], 0) < 0)
431 perror("dup2 stdin");
434 /* Redirect stdout. */
436 if (dup2(pout[1], 1) < 0)
437 perror("dup2 stdout");
440 /* Redirect stderr. */
442 if (dup2(perr[1], 2) < 0)
443 perror("dup2 stderr");
445 #else /* USE_PIPES */
447 * Redirect stdin, stdout, and stderr. Stdin and stdout will
448 * use the same socket, as some programs (particularly rdist)
449 * seem to depend on it.
453 if (dup2(inout[0], 0) < 0) /* stdin */
454 perror("dup2 stdin");
455 if (dup2(inout[0], 1) < 0) /* stdout. Note: same socket as stdin. */
456 perror("dup2 stdout");
457 if (dup2(err[0], 2) < 0) /* stderr */
458 perror("dup2 stderr");
459 #endif /* USE_PIPES */
462 cray_init_job(s->pw); /* set up cray jid and tmpdir */
465 /* Do processing for the child (exec command etc). */
466 do_child(s, command);
470 signal(WJSIGNAL, cray_job_termination_handler);
474 cygwin_set_impersonation_token(INVALID_HANDLE_VALUE);
477 packet_disconnect("fork failed: %.100s", strerror(errno));
479 /* Set interactive/non-interactive mode. */
480 packet_set_interactive(s->display != NULL);
482 /* We are the parent. Close the child sides of the pipes. */
488 if (s->is_subsystem) {
492 session_set_fds(s, pin[1], pout[0], perr[0]);
494 /* Enter the interactive session. */
495 server_loop(pid, pin[1], pout[0], perr[0]);
496 /* server_loop has closed pin[1], pout[0], and perr[0]. */
498 #else /* USE_PIPES */
499 /* We are the parent. Close the child sides of the socket pairs. */
504 * Clear loginmsg, since it's the child's responsibility to display
505 * it to the user, otherwise multiple sessions may accumulate
506 * multiple copies of the login messages.
508 buffer_clear(&loginmsg);
511 * Enter the interactive session. Note: server_loop must be able to
512 * handle the case that fdin and fdout are the same.
515 session_set_fds(s, inout[1], inout[1], s->is_subsystem ? -1 : err[1]);
517 server_loop(pid, inout[1], inout[1], err[1]);
518 /* server_loop has closed inout[1] and err[1]. */
520 #endif /* USE_PIPES */
524 * This is called to fork and execute a command when we have a tty. This
525 * will call do_child from the child, and server_loop from the parent after
526 * setting up file descriptors, controlling tty, updating wtmp, utmp,
527 * lastlog, and other such operations.
530 do_exec_pty(Session *s, const char *command)
532 int fdout, ptyfd, ttyfd, ptymaster;
536 fatal("do_exec_pty: no session");
541 if (options.use_pam) {
542 do_pam_set_tty(s->tty);
548 /* Fork the child. */
549 if ((pid = fork()) == 0) {
552 /* Child. Reinitialize the log because the pid has changed. */
553 log_init(__progname, options.log_level, options.log_facility, log_stderr);
554 /* Close the master side of the pseudo tty. */
557 /* Make the pseudo tty our controlling tty. */
558 pty_make_controlling_tty(&ttyfd, s->tty);
560 /* Redirect stdin/stdout/stderr from the pseudo tty. */
561 if (dup2(ttyfd, 0) < 0)
562 error("dup2 stdin: %s", strerror(errno));
563 if (dup2(ttyfd, 1) < 0)
564 error("dup2 stdout: %s", strerror(errno));
565 if (dup2(ttyfd, 2) < 0)
566 error("dup2 stderr: %s", strerror(errno));
568 /* Close the extra descriptor for the pseudo tty. */
571 /* record login, etc. similar to login(1) */
573 if (!(options.use_login && command == NULL)) {
575 cray_init_job(s->pw); /* set up cray jid and tmpdir */
577 do_login(s, command);
579 # ifdef LOGIN_NEEDS_UTMPX
585 /* Do common processing for the child, such as execing the command. */
586 do_child(s, command);
590 signal(WJSIGNAL, cray_job_termination_handler);
594 cygwin_set_impersonation_token(INVALID_HANDLE_VALUE);
597 packet_disconnect("fork failed: %.100s", strerror(errno));
600 /* Parent. Close the slave side of the pseudo tty. */
604 * Create another descriptor of the pty master side for use as the
605 * standard input. We could use the original descriptor, but this
606 * simplifies code in server_loop. The descriptor is bidirectional.
610 packet_disconnect("dup #1 failed: %.100s", strerror(errno));
612 /* we keep a reference to the pty master */
613 ptymaster = dup(ptyfd);
615 packet_disconnect("dup #2 failed: %.100s", strerror(errno));
616 s->ptymaster = ptymaster;
618 /* Enter interactive session. */
619 packet_set_interactive(1);
621 session_set_fds(s, ptyfd, fdout, -1);
623 server_loop(pid, ptyfd, fdout, -1);
624 /* server_loop _has_ closed ptyfd and fdout. */
628 #ifdef LOGIN_NEEDS_UTMPX
630 do_pre_login(Session *s)
633 struct sockaddr_storage from;
634 pid_t pid = getpid();
637 * Get IP address of client. If the connection is not a socket, let
638 * the address be 0.0.0.0.
640 memset(&from, 0, sizeof(from));
641 fromlen = sizeof(from);
642 if (packet_connection_is_on_socket()) {
643 if (getpeername(packet_get_connection_in(),
644 (struct sockaddr *) & from, &fromlen) < 0) {
645 debug("getpeername: %.100s", strerror(errno));
650 record_utmp_only(pid, s->tty, s->pw->pw_name,
651 get_remote_name_or_ip(utmp_len, options.use_dns),
652 (struct sockaddr *)&from, fromlen);
657 * This is called to fork and execute a command. If another command is
658 * to be forced, execute that instead.
661 do_exec(Session *s, const char *command)
663 if (forced_command) {
664 original_command = command;
665 command = forced_command;
666 debug("Forced command '%.900s'", command);
669 #ifdef SSH_AUDIT_EVENTS
671 PRIVSEP(audit_run_command(command));
672 else if (s->ttyfd == -1) {
673 char *shell = s->pw->pw_shell;
675 if (shell[0] == '\0') /* empty shell means /bin/sh */
677 PRIVSEP(audit_run_command(shell));
682 do_exec_pty(s, command);
684 do_exec_no_pty(s, command);
686 original_command = NULL;
689 * Clear loginmsg: it's the child's responsibility to display
690 * it to the user, otherwise multiple sessions may accumulate
691 * multiple copies of the login messages.
693 buffer_clear(&loginmsg);
696 /* administrative, login(1)-like work */
698 do_login(Session *s, const char *command)
701 struct sockaddr_storage from;
702 struct passwd * pw = s->pw;
703 pid_t pid = getpid();
706 * Get IP address of client. If the connection is not a socket, let
707 * the address be 0.0.0.0.
709 memset(&from, 0, sizeof(from));
710 fromlen = sizeof(from);
711 if (packet_connection_is_on_socket()) {
712 if (getpeername(packet_get_connection_in(),
713 (struct sockaddr *) & from, &fromlen) < 0) {
714 debug("getpeername: %.100s", strerror(errno));
719 /* Record that there was a login on that tty from the remote host. */
721 record_login(pid, s->tty, pw->pw_name, pw->pw_uid,
722 get_remote_name_or_ip(utmp_len,
724 (struct sockaddr *)&from, fromlen);
728 * If password change is needed, do it now.
729 * This needs to occur before the ~/.hushlogin check.
731 if (options.use_pam && !use_privsep && s->authctxt->force_pwchange) {
734 s->authctxt->force_pwchange = 0;
735 /* XXX - signal [net] parent to enable forwardings */
739 if (check_quietlogin(s, command))
748 * Display the message of the day.
755 #ifdef HAVE_LOGIN_CAP
759 #ifdef HAVE_LOGIN_CAP
760 fname = login_getcapstr(lc, "copyright", NULL, NULL);
761 if (fname != NULL && (f = fopen(fname, "r")) != NULL) {
762 while (fgets(buf, sizeof(buf), f) != NULL)
766 #endif /* HAVE_LOGIN_CAP */
767 (void)printf("%s\n\t%s %s\n",
768 "Copyright (c) 1980, 1983, 1986, 1988, 1990, 1991, 1993, 1994",
769 "The Regents of the University of California. ",
770 "All rights reserved.");
774 if (options.print_motd) {
775 #ifdef HAVE_LOGIN_CAP
776 f = fopen(login_getcapstr(lc, "welcome", "/etc/motd",
779 f = fopen("/etc/motd", "r");
782 while (fgets(buf, sizeof(buf), f))
791 * Check for quiet login, either .hushlogin or command given.
794 check_quietlogin(Session *s, const char *command)
797 struct passwd *pw = s->pw;
800 /* Return 1 if .hushlogin exists or a command given. */
803 snprintf(buf, sizeof(buf), "%.200s/.hushlogin", pw->pw_dir);
804 #ifdef HAVE_LOGIN_CAP
805 if (login_getcapbool(lc, "hushlogin", 0) || stat(buf, &st) >= 0)
808 if (stat(buf, &st) >= 0)
815 * Sets the value of the given variable in the environment. If the variable
816 * already exists, its value is overriden.
819 child_set_env(char ***envp, u_int *envsizep, const char *name,
827 * If we're passed an uninitialized list, allocate a single null
828 * entry before continuing.
830 if (*envp == NULL && *envsizep == 0) {
831 *envp = xmalloc(sizeof(char *));
837 * Find the slot where the value should be stored. If the variable
838 * already exists, we reuse the slot; otherwise we append a new slot
839 * at the end of the array, expanding if necessary.
842 namelen = strlen(name);
843 for (i = 0; env[i]; i++)
844 if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=')
847 /* Reuse the slot. */
850 /* New variable. Expand if necessary. */
852 if (i >= envsize - 1) {
854 fatal("child_set_env: too many env vars");
856 env = (*envp) = xrealloc(env, envsize * sizeof(char *));
859 /* Need to set the NULL pointer at end of array beyond the new slot. */
863 /* Allocate space and format the variable in the appropriate slot. */
864 env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1);
865 snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value);
869 * Reads environment variables from the given file and adds/overrides them
870 * into the environment. If the file does not exist, this does nothing.
871 * Otherwise, it must consist of empty lines, comments (line starts with '#')
872 * and assignments of the form name=value. No other forms are allowed.
875 read_environment_file(char ***env, u_int *envsize,
876 const char *filename)
883 f = fopen(filename, "r");
887 while (fgets(buf, sizeof(buf), f)) {
889 fatal("Too many lines in environment file %s", filename);
890 for (cp = buf; *cp == ' ' || *cp == '\t'; cp++)
892 if (!*cp || *cp == '#' || *cp == '\n')
894 if (strchr(cp, '\n'))
895 *strchr(cp, '\n') = '\0';
896 value = strchr(cp, '=');
898 fprintf(stderr, "Bad line %u in %.100s\n", lineno,
903 * Replace the equals sign by nul, and advance value to
908 child_set_env(env, envsize, cp, value);
913 #ifdef HAVE_ETC_DEFAULT_LOGIN
915 * Return named variable from specified environment, or NULL if not present.
918 child_get_env(char **env, const char *name)
924 for (i=0; env[i] != NULL; i++)
925 if (strncmp(name, env[i], len) == 0 && env[i][len] == '=')
926 return(env[i] + len + 1);
931 * Read /etc/default/login.
932 * We pick up the PATH (or SUPATH for root) and UMASK.
935 read_etc_default_login(char ***env, u_int *envsize, uid_t uid)
937 char **tmpenv = NULL, *var;
938 u_int i, tmpenvsize = 0;
942 * We don't want to copy the whole file to the child's environment,
943 * so we use a temporary environment and copy the variables we're
946 read_environment_file(&tmpenv, &tmpenvsize, "/etc/default/login");
952 var = child_get_env(tmpenv, "SUPATH");
954 var = child_get_env(tmpenv, "PATH");
956 child_set_env(env, envsize, "PATH", var);
958 if ((var = child_get_env(tmpenv, "UMASK")) != NULL)
959 if (sscanf(var, "%5lo", &mask) == 1)
962 for (i = 0; tmpenv[i] != NULL; i++)
966 #endif /* HAVE_ETC_DEFAULT_LOGIN */
968 void copy_environment(char **source, char ***env, u_int *envsize)
970 char *var_name, *var_val;
976 for(i = 0; source[i] != NULL; i++) {
977 var_name = xstrdup(source[i]);
978 if ((var_val = strstr(var_name, "=")) == NULL) {
984 debug3("Copy environment: %s=%s", var_name, var_val);
985 child_set_env(env, envsize, var_name, var_val);
992 do_setup_env(Session *s, const char *shell)
996 char **env, *laddr, *path = NULL;
997 #ifdef HAVE_LOGIN_CAP
998 extern char **environ;
1001 struct passwd *pw = s->pw;
1003 /* Initialize the environment. */
1005 env = xmalloc(envsize * sizeof(char *));
1010 * The Windows environment contains some setting which are
1011 * important for a running system. They must not be dropped.
1016 p = fetch_windows_environment();
1017 copy_environment(p, &env, &envsize);
1018 free_windows_environment(p);
1023 child_set_env(&env, &envsize, "TZ", getenv("TZ"));
1026 /* Allow any GSSAPI methods that we've used to alter
1027 * the childs environment as they see fit
1029 ssh_gssapi_do_child(&env, &envsize);
1032 if (!options.use_login) {
1033 /* Set basic environment. */
1034 for (i = 0; i < s->num_env; i++)
1035 child_set_env(&env, &envsize, s->env[i].name,
1038 child_set_env(&env, &envsize, "USER", pw->pw_name);
1039 child_set_env(&env, &envsize, "LOGNAME", pw->pw_name);
1041 child_set_env(&env, &envsize, "LOGIN", pw->pw_name);
1043 child_set_env(&env, &envsize, "HOME", pw->pw_dir);
1044 snprintf(buf, sizeof buf, "%.200s/%.50s",
1045 _PATH_MAILDIR, pw->pw_name);
1046 child_set_env(&env, &envsize, "MAIL", buf);
1047 #ifdef HAVE_LOGIN_CAP
1048 child_set_env(&env, &envsize, "PATH", _PATH_STDPATH);
1049 child_set_env(&env, &envsize, "TERM", "su");
1051 environ = xmalloc(sizeof(char *));
1053 (void) setusercontext(lc, pw, pw->pw_uid,
1054 LOGIN_SETENV|LOGIN_SETPATH);
1055 copy_environment(environ, &env, &envsize);
1056 for (var = environ; *var != NULL; ++var)
1060 #else /* HAVE_LOGIN_CAP */
1061 # ifndef HAVE_CYGWIN
1063 * There's no standard path on Windows. The path contains
1064 * important components pointing to the system directories,
1065 * needed for loading shared libraries. So the path better
1066 * remains intact here.
1068 # ifdef HAVE_ETC_DEFAULT_LOGIN
1069 read_etc_default_login(&env, &envsize, pw->pw_uid);
1070 path = child_get_env(env, "PATH");
1071 # endif /* HAVE_ETC_DEFAULT_LOGIN */
1072 if (path == NULL || *path == '\0') {
1073 child_set_env(&env, &envsize, "PATH",
1074 s->pw->pw_uid == 0 ?
1075 SUPERUSER_PATH : _PATH_STDPATH);
1077 # endif /* HAVE_CYGWIN */
1078 #endif /* HAVE_LOGIN_CAP */
1080 /* Normal systems set SHELL by default. */
1081 child_set_env(&env, &envsize, "SHELL", shell);
1084 /* Set custom environment options from RSA authentication. */
1085 if (!options.use_login) {
1086 while (custom_environment) {
1087 struct envstring *ce = custom_environment;
1090 for (i = 0; str[i] != '=' && str[i]; i++)
1092 if (str[i] == '=') {
1094 child_set_env(&env, &envsize, str, str + i + 1);
1096 custom_environment = ce->next;
1102 /* SSH_CLIENT deprecated */
1103 snprintf(buf, sizeof buf, "%.50s %d %d",
1104 get_remote_ipaddr(), get_remote_port(), get_local_port());
1105 child_set_env(&env, &envsize, "SSH_CLIENT", buf);
1107 laddr = get_local_ipaddr(packet_get_connection_in());
1108 snprintf(buf, sizeof buf, "%.50s %d %.50s %d",
1109 get_remote_ipaddr(), get_remote_port(), laddr, get_local_port());
1111 child_set_env(&env, &envsize, "SSH_CONNECTION", buf);
1114 child_set_env(&env, &envsize, "SSH_TTY", s->tty);
1116 child_set_env(&env, &envsize, "TERM", s->term);
1118 child_set_env(&env, &envsize, "DISPLAY", s->display);
1119 if (original_command)
1120 child_set_env(&env, &envsize, "SSH_ORIGINAL_COMMAND",
1124 if (cray_tmpdir[0] != '\0')
1125 child_set_env(&env, &envsize, "TMPDIR", cray_tmpdir);
1126 #endif /* _UNICOS */
1129 * Since we clear KRB5CCNAME at startup, if it's set now then it
1130 * must have been set by a native authentication method (eg AIX or
1131 * SIA), so copy it to the child.
1136 if ((cp = getenv("KRB5CCNAME")) != NULL)
1137 child_set_env(&env, &envsize, "KRB5CCNAME", cp);
1144 if ((cp = getenv("AUTHSTATE")) != NULL)
1145 child_set_env(&env, &envsize, "AUTHSTATE", cp);
1146 read_environment_file(&env, &envsize, "/etc/environment");
1150 if (s->authctxt->krb5_ccname)
1151 child_set_env(&env, &envsize, "KRB5CCNAME",
1152 s->authctxt->krb5_ccname);
1156 * Pull in any environment variables that may have
1159 if (options.use_pam) {
1162 p = fetch_pam_child_environment();
1163 copy_environment(p, &env, &envsize);
1164 free_pam_environment(p);
1166 p = fetch_pam_environment();
1167 copy_environment(p, &env, &envsize);
1168 free_pam_environment(p);
1170 #endif /* USE_PAM */
1172 if (auth_sock_name != NULL)
1173 child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME,
1176 /* read $HOME/.ssh/environment. */
1177 if (options.permit_user_env && !options.use_login) {
1178 snprintf(buf, sizeof buf, "%.200s/.ssh/environment",
1179 strcmp(pw->pw_dir, "/") ? pw->pw_dir : "");
1180 read_environment_file(&env, &envsize, buf);
1183 /* dump the environment */
1184 fprintf(stderr, "Environment:\n");
1185 for (i = 0; env[i]; i++)
1186 fprintf(stderr, " %.200s\n", env[i]);
1192 * Run $HOME/.ssh/rc, /etc/ssh/sshrc, or xauth (whichever is found
1193 * first in this order).
1196 do_rc_files(Session *s, const char *shell)
1204 s->display != NULL && s->auth_proto != NULL && s->auth_data != NULL;
1206 /* ignore _PATH_SSH_USER_RC for subsystems */
1207 if (!s->is_subsystem && (stat(_PATH_SSH_USER_RC, &st) >= 0)) {
1208 snprintf(cmd, sizeof cmd, "%s -c '%s %s'",
1209 shell, _PATH_BSHELL, _PATH_SSH_USER_RC);
1211 fprintf(stderr, "Running %s\n", cmd);
1212 f = popen(cmd, "w");
1215 fprintf(f, "%s %s\n", s->auth_proto,
1219 fprintf(stderr, "Could not run %s\n",
1221 } else if (stat(_PATH_SSH_SYSTEM_RC, &st) >= 0) {
1223 fprintf(stderr, "Running %s %s\n", _PATH_BSHELL,
1224 _PATH_SSH_SYSTEM_RC);
1225 f = popen(_PATH_BSHELL " " _PATH_SSH_SYSTEM_RC, "w");
1228 fprintf(f, "%s %s\n", s->auth_proto,
1232 fprintf(stderr, "Could not run %s\n",
1233 _PATH_SSH_SYSTEM_RC);
1234 } else if (do_xauth && options.xauth_location != NULL) {
1235 /* Add authority data to .Xauthority if appropriate. */
1238 "Running %.500s remove %.100s\n",
1239 options.xauth_location, s->auth_display);
1241 "%.500s add %.100s %.100s %.100s\n",
1242 options.xauth_location, s->auth_display,
1243 s->auth_proto, s->auth_data);
1245 snprintf(cmd, sizeof cmd, "%s -q -",
1246 options.xauth_location);
1247 f = popen(cmd, "w");
1249 fprintf(f, "remove %s\n",
1251 fprintf(f, "add %s %s %s\n",
1252 s->auth_display, s->auth_proto,
1256 fprintf(stderr, "Could not run %s\n",
1263 do_nologin(struct passwd *pw)
1268 #ifdef HAVE_LOGIN_CAP
1269 if (!login_getcapbool(lc, "ignorenologin", 0) && pw->pw_uid)
1270 f = fopen(login_getcapstr(lc, "nologin", _PATH_NOLOGIN,
1271 _PATH_NOLOGIN), "r");
1274 f = fopen(_PATH_NOLOGIN, "r");
1277 /* /etc/nologin exists. Print its contents and exit. */
1278 logit("User %.100s not allowed because %s exists",
1279 pw->pw_name, _PATH_NOLOGIN);
1280 while (fgets(buf, sizeof(buf), f))
1288 /* Set login name, uid, gid, and groups. */
1290 do_setusercontext(struct passwd *pw)
1293 if (getuid() == 0 || geteuid() == 0)
1294 #endif /* HAVE_CYGWIN */
1297 #ifdef HAVE_SETPCRED
1298 if (setpcred(pw->pw_name, (char **)NULL) == -1)
1299 fatal("Failed to set process credentials");
1300 #endif /* HAVE_SETPCRED */
1301 #ifdef HAVE_LOGIN_CAP
1306 if (options.gss_authentication) {
1307 temporarily_use_uid(pw);
1308 ssh_gssapi_storecreds();
1313 if (options.use_pam) {
1317 # endif /* USE_PAM */
1318 if (setusercontext(lc, pw, pw->pw_uid,
1319 (LOGIN_SETALL & ~(LOGIN_SETENV|LOGIN_SETPATH))) < 0) {
1320 perror("unable to set user context");
1324 # if defined(HAVE_GETLUID) && defined(HAVE_SETLUID)
1325 /* Sets login uid for accounting */
1326 if (getluid() == -1 && setluid(pw->pw_uid) == -1)
1327 error("setluid: %s", strerror(errno));
1328 # endif /* defined(HAVE_GETLUID) && defined(HAVE_SETLUID) */
1330 if (setlogin(pw->pw_name) < 0)
1331 error("setlogin failed: %s", strerror(errno));
1332 if (setgid(pw->pw_gid) < 0) {
1336 /* Initialize the group list. */
1337 if (initgroups(pw->pw_name, pw->pw_gid) < 0) {
1338 perror("initgroups");
1343 if (options.gss_authentication) {
1344 temporarily_use_uid(pw);
1345 ssh_gssapi_storecreds();
1351 * PAM credentials may take the form of supplementary groups.
1352 * These will have been wiped by the above initgroups() call.
1353 * Reestablish them here.
1355 if (options.use_pam) {
1359 # endif /* USE_PAM */
1360 # if defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY)
1361 irix_setusercontext(pw);
1362 # endif /* defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) */
1366 /* Permanently switch to the desired uid. */
1367 permanently_set_uid(pw);
1374 if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid)
1375 fatal("Failed to set uids to %u.", (u_int) pw->pw_uid);
1379 do_pwchange(Session *s)
1382 fprintf(stderr, "WARNING: Your password has expired.\n");
1383 if (s->ttyfd != -1) {
1385 "You must change your password now and login again!\n");
1386 #ifdef PASSWD_NEEDS_USERNAME
1387 execl(_PATH_PASSWD_PROG, "passwd", s->pw->pw_name,
1390 execl(_PATH_PASSWD_PROG, "passwd", (char *)NULL);
1395 "Password change required but no TTY available.\n");
1401 launch_login(struct passwd *pw, const char *hostname)
1403 /* Launch login(1). */
1405 execl(LOGIN_PROGRAM, "login", "-h", hostname,
1406 #ifdef xxxLOGIN_NEEDS_TERM
1407 (s->term ? s->term : "unknown"),
1408 #endif /* LOGIN_NEEDS_TERM */
1409 #ifdef LOGIN_NO_ENDOPT
1410 "-p", "-f", pw->pw_name, (char *)NULL);
1412 "-p", "-f", "--", pw->pw_name, (char *)NULL);
1415 /* Login couldn't be executed, die. */
1422 child_close_fds(void)
1426 if (packet_get_connection_in() == packet_get_connection_out())
1427 close(packet_get_connection_in());
1429 close(packet_get_connection_in());
1430 close(packet_get_connection_out());
1433 * Close all descriptors related to channels. They will still remain
1434 * open in the parent.
1436 /* XXX better use close-on-exec? -markus */
1437 channel_close_all();
1440 * Close any extra file descriptors. Note that there may still be
1441 * descriptors left by system functions. They will be closed later.
1446 * Close any extra open file descriptors so that we don\'t have them
1447 * hanging around in clients. Note that we want to do this after
1448 * initgroups, because at least on Solaris 2.3 it leaves file
1451 for (i = 3; i < 64; i++)
1456 * Performs common processing for the child, such as setting up the
1457 * environment, closing extra file descriptors, setting the user and group
1458 * ids, and executing the command or shell.
1461 do_child(Session *s, const char *command)
1463 extern char **environ;
1466 const char *shell, *shell0, *hostname = NULL;
1467 struct passwd *pw = s->pw;
1468 #ifdef HAVE_LOGIN_CAP
1472 /* remove hostkey from the child's memory */
1473 destroy_sensitive_data();
1475 /* Force a password change */
1476 if (s->authctxt->force_pwchange) {
1477 do_setusercontext(pw);
1483 /* login(1) is only called if we execute the login shell */
1484 if (options.use_login && command != NULL)
1485 options.use_login = 0;
1488 cray_setup(pw->pw_uid, pw->pw_name, command);
1489 #endif /* _UNICOS */
1492 * Login(1) does this as well, and it needs uid 0 for the "-h"
1493 * switch, so we let login(1) to this for us.
1495 if (!options.use_login) {
1497 session_setup_sia(pw, s->ttyfd == -1 ? NULL : s->tty);
1498 if (!check_quietlogin(s, command))
1500 #else /* HAVE_OSF_SIA */
1502 do_setusercontext(pw);
1504 * PAM session modules in do_setusercontext may have
1505 * generated messages, so if this in an interactive
1506 * login then display them too.
1508 if (!check_quietlogin(s, command))
1510 #endif /* HAVE_OSF_SIA */
1514 if (options.use_pam && !options.use_login && !is_pam_session_open()) {
1515 debug3("PAM session not opened, exiting");
1522 * Get the shell from the password data. An empty shell field is
1523 * legal, and means /bin/sh.
1525 shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
1528 * Make sure $SHELL points to the shell from the password file,
1529 * even if shell is overridden from login.conf
1531 env = do_setup_env(s, shell);
1533 #ifdef HAVE_LOGIN_CAP
1534 shell = login_getcapstr(lc, "shell", (char *)shell, (char *)shell);
1537 /* we have to stash the hostname before we close our socket. */
1538 if (options.use_login)
1539 hostname = get_remote_name_or_ip(utmp_len,
1542 * Close the connection descriptors; note that this is the child, and
1543 * the server will still have the socket open, and it is important
1544 * that we do not shutdown it. Note that the descriptors cannot be
1545 * closed before building the environment, as we call
1546 * get_remote_ipaddr there.
1551 * Must take new environment into use so that .ssh/rc,
1552 * /etc/ssh/sshrc and xauth are run in the proper environment.
1556 #ifdef HAVE_LOGIN_CAP
1557 lc_requirehome = login_getcapbool(lc, "requirehome", 0);
1560 #if defined(KRB5) && defined(USE_AFS)
1562 * At this point, we check to see if AFS is active and if we have
1563 * a valid Kerberos 5 TGT. If so, it seems like a good idea to see
1564 * if we can (and need to) extend the ticket into an AFS token. If
1565 * we don't do this, we run into potential problems if the user's
1566 * home directory is in AFS and it's not world-readable.
1569 if (options.kerberos_get_afs_token && k_hasafs() &&
1570 (s->authctxt->krb5_ctx != NULL)) {
1573 debug("Getting AFS token");
1577 if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0)
1578 krb5_afslog(s->authctxt->krb5_ctx,
1579 s->authctxt->krb5_fwd_ccache, cell, NULL);
1581 krb5_afslog_home(s->authctxt->krb5_ctx,
1582 s->authctxt->krb5_fwd_ccache, NULL, NULL, pw->pw_dir);
1586 /* Change current directory to the user\'s home directory. */
1587 if (chdir(pw->pw_dir) < 0) {
1588 fprintf(stderr, "Could not chdir to home directory %s: %s\n",
1589 pw->pw_dir, strerror(errno));
1590 #ifdef HAVE_LOGIN_CAP
1596 if (!options.use_login)
1597 do_rc_files(s, shell);
1599 /* restore SIGPIPE for child */
1600 signal(SIGPIPE, SIG_DFL);
1602 if (options.use_login) {
1603 launch_login(pw, hostname);
1607 /* Get the last component of the shell name. */
1608 if ((shell0 = strrchr(shell, '/')) != NULL)
1614 * If we have no command, execute the shell. In this case, the shell
1615 * name to be passed in argv[0] is preceded by '-' to indicate that
1616 * this is a login shell.
1621 /* Start the shell. Set initial character to '-'. */
1624 if (strlcpy(argv0 + 1, shell0, sizeof(argv0) - 1)
1625 >= sizeof(argv0) - 1) {
1631 /* Execute the shell. */
1634 execve(shell, argv, env);
1636 /* Executing the shell failed. */
1641 * Execute the command using the user's shell. This uses the -c
1642 * option to execute the command.
1644 argv[0] = (char *) shell0;
1646 argv[2] = (char *) command;
1648 execve(shell, argv, env);
1657 static int did_init = 0;
1659 debug("session_new: init");
1660 for (i = 0; i < MAX_SESSIONS; i++) {
1661 sessions[i].used = 0;
1665 for (i = 0; i < MAX_SESSIONS; i++) {
1666 Session *s = &sessions[i];
1668 memset(s, 0, sizeof(*s));
1674 debug("session_new: session %d", i);
1685 for (i = 0; i < MAX_SESSIONS; i++) {
1686 Session *s = &sessions[i];
1687 debug("dump: used %d session %d %p channel %d pid %ld",
1697 session_open(Authctxt *authctxt, int chanid)
1699 Session *s = session_new();
1700 debug("session_open: channel %d", chanid);
1702 error("no more sessions");
1705 s->authctxt = authctxt;
1706 s->pw = authctxt->pw;
1707 if (s->pw == NULL || !authctxt->valid)
1708 fatal("no user for session %d", s->self);
1709 debug("session_open: session %d: link with channel %d", s->self, chanid);
1715 session_by_tty(char *tty)
1718 for (i = 0; i < MAX_SESSIONS; i++) {
1719 Session *s = &sessions[i];
1720 if (s->used && s->ttyfd != -1 && strcmp(s->tty, tty) == 0) {
1721 debug("session_by_tty: session %d tty %s", i, tty);
1725 debug("session_by_tty: unknown tty %.100s", tty);
1731 session_by_channel(int id)
1734 for (i = 0; i < MAX_SESSIONS; i++) {
1735 Session *s = &sessions[i];
1736 if (s->used && s->chanid == id) {
1737 debug("session_by_channel: session %d channel %d", i, id);
1741 debug("session_by_channel: unknown channel %d", id);
1747 session_by_pid(pid_t pid)
1750 debug("session_by_pid: pid %ld", (long)pid);
1751 for (i = 0; i < MAX_SESSIONS; i++) {
1752 Session *s = &sessions[i];
1753 if (s->used && s->pid == pid)
1756 error("session_by_pid: unknown pid %ld", (long)pid);
1762 session_window_change_req(Session *s)
1764 s->col = packet_get_int();
1765 s->row = packet_get_int();
1766 s->xpixel = packet_get_int();
1767 s->ypixel = packet_get_int();
1769 pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1774 session_pty_req(Session *s)
1780 debug("Allocating a pty not permitted for this authentication.");
1783 if (s->ttyfd != -1) {
1784 packet_disconnect("Protocol error: you already have a pty.");
1788 s->term = packet_get_string(&len);
1791 s->col = packet_get_int();
1792 s->row = packet_get_int();
1794 s->row = packet_get_int();
1795 s->col = packet_get_int();
1797 s->xpixel = packet_get_int();
1798 s->ypixel = packet_get_int();
1800 if (strcmp(s->term, "") == 0) {
1805 /* Allocate a pty and open it. */
1806 debug("Allocating pty.");
1807 if (!PRIVSEP(pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty)))) {
1813 error("session_pty_req: session %d alloc failed", s->self);
1816 debug("session_pty_req: session %d alloc %s", s->self, s->tty);
1818 /* for SSH1 the tty modes length is not given */
1820 n_bytes = packet_remaining();
1821 tty_parse_modes(s->ttyfd, &n_bytes);
1824 pty_setowner(s->pw, s->tty);
1826 /* Set window size from the packet. */
1827 pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1830 session_proctitle(s);
1835 session_subsystem_req(Session *s)
1840 char *cmd, *subsys = packet_get_string(&len);
1844 logit("subsystem request for %.100s", subsys);
1846 for (i = 0; i < options.num_subsystems; i++) {
1847 if (strcmp(subsys, options.subsystem_name[i]) == 0) {
1848 cmd = options.subsystem_command[i];
1849 if (stat(cmd, &st) < 0) {
1850 error("subsystem: cannot stat %s: %s", cmd,
1854 debug("subsystem: exec() %s", cmd);
1855 s->is_subsystem = 1;
1863 logit("subsystem request for %.100s failed, subsystem not found",
1871 session_x11_req(Session *s)
1875 s->single_connection = packet_get_char();
1876 s->auth_proto = packet_get_string(NULL);
1877 s->auth_data = packet_get_string(NULL);
1878 s->screen = packet_get_int();
1881 success = session_setup_x11fwd(s);
1883 xfree(s->auth_proto);
1884 xfree(s->auth_data);
1885 s->auth_proto = NULL;
1886 s->auth_data = NULL;
1892 session_shell_req(Session *s)
1900 session_exec_req(Session *s)
1903 char *command = packet_get_string(&len);
1905 do_exec(s, command);
1911 session_break_req(Session *s)
1914 packet_get_int(); /* ignored */
1917 if (s->ttyfd == -1 ||
1918 tcsendbreak(s->ttyfd, 0) < 0)
1924 session_env_req(Session *s)
1927 u_int name_len, val_len, i;
1929 name = packet_get_string(&name_len);
1930 val = packet_get_string(&val_len);
1933 /* Don't set too many environment variables */
1934 if (s->num_env > 128) {
1935 debug2("Ignoring env request %s: too many env vars", name);
1939 for (i = 0; i < options.num_accept_env; i++) {
1940 if (match_pattern(name, options.accept_env[i])) {
1941 debug2("Setting env %d: %s=%s", s->num_env, name, val);
1942 s->env = xrealloc(s->env, sizeof(*s->env) *
1944 s->env[s->num_env].name = name;
1945 s->env[s->num_env].val = val;
1950 debug2("Ignoring env request %s: disallowed name", name);
1959 session_auth_agent_req(Session *s)
1961 static int called = 0;
1963 if (no_agent_forwarding_flag) {
1964 debug("session_auth_agent_req: no_agent_forwarding_flag");
1971 return auth_input_request_forwarding(s->pw);
1976 session_input_channel_req(Channel *c, const char *rtype)
1981 if ((s = session_by_channel(c->self)) == NULL) {
1982 logit("session_input_channel_req: no session %d req %.100s",
1986 debug("session_input_channel_req: session %d req %s", s->self, rtype);
1989 * a session is in LARVAL state until a shell, a command
1990 * or a subsystem is executed
1992 if (c->type == SSH_CHANNEL_LARVAL) {
1993 if (strcmp(rtype, "shell") == 0) {
1994 success = session_shell_req(s);
1995 } else if (strcmp(rtype, "exec") == 0) {
1996 success = session_exec_req(s);
1997 } else if (strcmp(rtype, "pty-req") == 0) {
1998 success = session_pty_req(s);
1999 } else if (strcmp(rtype, "x11-req") == 0) {
2000 success = session_x11_req(s);
2001 } else if (strcmp(rtype, "auth-agent-req@openssh.com") == 0) {
2002 success = session_auth_agent_req(s);
2003 } else if (strcmp(rtype, "subsystem") == 0) {
2004 success = session_subsystem_req(s);
2005 } else if (strcmp(rtype, "env") == 0) {
2006 success = session_env_req(s);
2009 if (strcmp(rtype, "window-change") == 0) {
2010 success = session_window_change_req(s);
2011 } else if (strcmp(rtype, "break") == 0) {
2012 success = session_break_req(s);
2019 session_set_fds(Session *s, int fdin, int fdout, int fderr)
2022 fatal("session_set_fds: called for proto != 2.0");
2024 * now that have a child and a pipe to the child,
2025 * we can activate our channel and register the fd's
2027 if (s->chanid == -1)
2028 fatal("no channel for session %d", s->self);
2029 channel_set_fds(s->chanid,
2031 fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ,
2033 CHAN_SES_WINDOW_DEFAULT);
2037 * Function to perform pty cleanup. Also called if we get aborted abnormally
2038 * (e.g., due to a dropped connection).
2041 session_pty_cleanup2(Session *s)
2044 error("session_pty_cleanup: no session");
2050 debug("session_pty_cleanup: session %d release %s", s->self, s->tty);
2052 /* Record that the user has logged out. */
2054 record_logout(s->pid, s->tty, s->pw->pw_name);
2056 /* Release the pseudo-tty. */
2058 pty_release(s->tty);
2061 * Close the server side of the socket pairs. We must do this after
2062 * the pty cleanup, so that another process doesn't get this pty
2063 * while we're still cleaning up.
2065 if (close(s->ptymaster) < 0)
2066 error("close(s->ptymaster/%d): %s", s->ptymaster, strerror(errno));
2068 /* unlink pty from session */
2073 session_pty_cleanup(Session *s)
2075 PRIVSEP(session_pty_cleanup2(s));
2081 #define SSH_SIG(x) if (sig == SIG ## x) return #x
2096 return "SIG@openssh.com";
2100 session_exit_message(Session *s, int status)
2104 if ((c = channel_lookup(s->chanid)) == NULL)
2105 fatal("session_exit_message: session %d: no channel %d",
2106 s->self, s->chanid);
2107 debug("session_exit_message: session %d channel %d pid %ld",
2108 s->self, s->chanid, (long)s->pid);
2110 if (WIFEXITED(status)) {
2111 channel_request_start(s->chanid, "exit-status", 0);
2112 packet_put_int(WEXITSTATUS(status));
2114 } else if (WIFSIGNALED(status)) {
2115 channel_request_start(s->chanid, "exit-signal", 0);
2116 packet_put_cstring(sig2name(WTERMSIG(status)));
2118 packet_put_char(WCOREDUMP(status));
2119 #else /* WCOREDUMP */
2121 #endif /* WCOREDUMP */
2122 packet_put_cstring("");
2123 packet_put_cstring("");
2126 /* Some weird exit cause. Just exit. */
2127 packet_disconnect("wait returned status %04x.", status);
2130 /* disconnect channel */
2131 debug("session_exit_message: release channel %d", s->chanid);
2132 channel_cancel_cleanup(s->chanid);
2134 * emulate a write failure with 'chan_write_failed', nobody will be
2135 * interested in data we write.
2136 * Note that we must not call 'chan_read_failed', since there could
2137 * be some more data waiting in the pipe.
2139 if (c->ostate != CHAN_OUTPUT_CLOSED)
2140 chan_write_failed(c);
2145 session_close(Session *s)
2149 debug("session_close: session %d pid %ld", s->self, (long)s->pid);
2151 session_pty_cleanup(s);
2156 if (s->auth_display)
2157 xfree(s->auth_display);
2159 xfree(s->auth_data);
2161 xfree(s->auth_proto);
2163 for (i = 0; i < s->num_env; i++) {
2164 xfree(s->env[i].name);
2165 xfree(s->env[i].val);
2169 session_proctitle(s);
2173 session_close_by_pid(pid_t pid, int status)
2175 Session *s = session_by_pid(pid);
2177 debug("session_close_by_pid: no session for pid %ld",
2181 if (s->chanid != -1)
2182 session_exit_message(s, status);
2187 * this is called when a channel dies before
2188 * the session 'child' itself dies
2191 session_close_by_channel(int id, void *arg)
2193 Session *s = session_by_channel(id);
2195 debug("session_close_by_channel: no session for id %d", id);
2198 debug("session_close_by_channel: channel %d child %ld",
2201 debug("session_close_by_channel: channel %d: has child", id);
2203 * delay detach of session, but release pty, since
2204 * the fd's to the child are already closed
2207 session_pty_cleanup(s);
2210 /* detach by removing callback */
2211 channel_cancel_cleanup(s->chanid);
2217 session_destroy_all(void (*closefunc)(Session *))
2220 for (i = 0; i < MAX_SESSIONS; i++) {
2221 Session *s = &sessions[i];
2223 if (closefunc != NULL)
2232 session_tty_list(void)
2234 static char buf[1024];
2239 for (i = 0; i < MAX_SESSIONS; i++) {
2240 Session *s = &sessions[i];
2241 if (s->used && s->ttyfd != -1) {
2243 if (strncmp(s->tty, "/dev/", 5) != 0) {
2244 cp = strrchr(s->tty, '/');
2245 cp = (cp == NULL) ? s->tty : cp + 1;
2250 strlcat(buf, ",", sizeof buf);
2251 strlcat(buf, cp, sizeof buf);
2255 strlcpy(buf, "notty", sizeof buf);
2260 session_proctitle(Session *s)
2263 error("no user for session %d", s->self);
2265 setproctitle("%s@%s", s->pw->pw_name, session_tty_list());
2269 session_setup_x11fwd(Session *s)
2272 char display[512], auth_display[512];
2273 char hostname[MAXHOSTNAMELEN];
2275 if (no_x11_forwarding_flag) {
2276 packet_send_debug("X11 forwarding disabled in user configuration file.");
2279 if (!options.x11_forwarding) {
2280 debug("X11 forwarding disabled in server configuration file.");
2283 if (!options.xauth_location ||
2284 (stat(options.xauth_location, &st) == -1)) {
2285 packet_send_debug("No xauth program; cannot forward with spoofing.");
2288 if (options.use_login) {
2289 packet_send_debug("X11 forwarding disabled; "
2290 "not compatible with UseLogin=yes.");
2293 if (s->display != NULL) {
2294 debug("X11 display already set.");
2297 if (x11_create_display_inet(options.x11_display_offset,
2298 options.x11_use_localhost, s->single_connection,
2299 &s->display_number) == -1) {
2300 debug("x11_create_display_inet failed.");
2304 /* Set up a suitable value for the DISPLAY variable. */
2305 if (gethostname(hostname, sizeof(hostname)) < 0)
2306 fatal("gethostname: %.100s", strerror(errno));
2308 * auth_display must be used as the displayname when the
2309 * authorization entry is added with xauth(1). This will be
2310 * different than the DISPLAY string for localhost displays.
2312 if (options.x11_use_localhost) {
2313 snprintf(display, sizeof display, "localhost:%u.%u",
2314 s->display_number, s->screen);
2315 snprintf(auth_display, sizeof auth_display, "unix:%u.%u",
2316 s->display_number, s->screen);
2317 s->display = xstrdup(display);
2318 s->auth_display = xstrdup(auth_display);
2320 #ifdef IPADDR_IN_DISPLAY
2322 struct in_addr my_addr;
2324 he = gethostbyname(hostname);
2326 error("Can't get IP address for X11 DISPLAY.");
2327 packet_send_debug("Can't get IP address for X11 DISPLAY.");
2330 memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr));
2331 snprintf(display, sizeof display, "%.50s:%u.%u", inet_ntoa(my_addr),
2332 s->display_number, s->screen);
2334 snprintf(display, sizeof display, "%.400s:%u.%u", hostname,
2335 s->display_number, s->screen);
2337 s->display = xstrdup(display);
2338 s->auth_display = xstrdup(display);
2345 do_authenticated2(Authctxt *authctxt)
2347 server_loop2(authctxt);
2351 do_cleanup(Authctxt *authctxt)
2353 static int called = 0;
2355 debug("do_cleanup");
2357 /* no cleanup if we're in the child for login shell */
2361 /* avoid double cleanup */
2366 if (authctxt == NULL)
2369 if (options.kerberos_ticket_cleanup &&
2371 krb5_cleanup_proc(authctxt);
2375 if (compat20 && options.gss_cleanup_creds)
2376 ssh_gssapi_cleanup_creds();
2380 if (options.use_pam) {
2382 sshpam_thread_cleanup();
2386 /* remove agent socket */
2387 auth_sock_cleanup_proc(authctxt->pw);
2390 * Cleanup ptys/utmp only if privsep is disabled,
2391 * or if running in monitor.
2393 if (!use_privsep || mm_is_monitor())
2394 session_destroy_all(session_pty_cleanup2);