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 1.186 2005/07/25 11:59:40 markus Exp $");
51 #include "auth-options.h"
52 #include "pathnames.h"
56 #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 == COMP_NONE) {
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.
756 if (options.print_motd) {
757 #ifdef HAVE_LOGIN_CAP
758 f = fopen(login_getcapstr(lc, "welcome", "/etc/motd",
761 f = fopen("/etc/motd", "r");
764 while (fgets(buf, sizeof(buf), f))
773 * Check for quiet login, either .hushlogin or command given.
776 check_quietlogin(Session *s, const char *command)
779 struct passwd *pw = s->pw;
782 /* Return 1 if .hushlogin exists or a command given. */
785 snprintf(buf, sizeof(buf), "%.200s/.hushlogin", pw->pw_dir);
786 #ifdef HAVE_LOGIN_CAP
787 if (login_getcapbool(lc, "hushlogin", 0) || stat(buf, &st) >= 0)
790 if (stat(buf, &st) >= 0)
797 * Sets the value of the given variable in the environment. If the variable
798 * already exists, its value is overriden.
801 child_set_env(char ***envp, u_int *envsizep, const char *name,
809 * If we're passed an uninitialized list, allocate a single null
810 * entry before continuing.
812 if (*envp == NULL && *envsizep == 0) {
813 *envp = xmalloc(sizeof(char *));
819 * Find the slot where the value should be stored. If the variable
820 * already exists, we reuse the slot; otherwise we append a new slot
821 * at the end of the array, expanding if necessary.
824 namelen = strlen(name);
825 for (i = 0; env[i]; i++)
826 if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=')
829 /* Reuse the slot. */
832 /* New variable. Expand if necessary. */
834 if (i >= envsize - 1) {
836 fatal("child_set_env: too many env vars");
838 env = (*envp) = xrealloc(env, envsize * sizeof(char *));
841 /* Need to set the NULL pointer at end of array beyond the new slot. */
845 /* Allocate space and format the variable in the appropriate slot. */
846 env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1);
847 snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value);
851 * Reads environment variables from the given file and adds/overrides them
852 * into the environment. If the file does not exist, this does nothing.
853 * Otherwise, it must consist of empty lines, comments (line starts with '#')
854 * and assignments of the form name=value. No other forms are allowed.
857 read_environment_file(char ***env, u_int *envsize,
858 const char *filename)
865 f = fopen(filename, "r");
869 while (fgets(buf, sizeof(buf), f)) {
871 fatal("Too many lines in environment file %s", filename);
872 for (cp = buf; *cp == ' ' || *cp == '\t'; cp++)
874 if (!*cp || *cp == '#' || *cp == '\n')
876 if (strchr(cp, '\n'))
877 *strchr(cp, '\n') = '\0';
878 value = strchr(cp, '=');
880 fprintf(stderr, "Bad line %u in %.100s\n", lineno,
885 * Replace the equals sign by nul, and advance value to
890 child_set_env(env, envsize, cp, value);
895 #ifdef HAVE_ETC_DEFAULT_LOGIN
897 * Return named variable from specified environment, or NULL if not present.
900 child_get_env(char **env, const char *name)
906 for (i=0; env[i] != NULL; i++)
907 if (strncmp(name, env[i], len) == 0 && env[i][len] == '=')
908 return(env[i] + len + 1);
913 * Read /etc/default/login.
914 * We pick up the PATH (or SUPATH for root) and UMASK.
917 read_etc_default_login(char ***env, u_int *envsize, uid_t uid)
919 char **tmpenv = NULL, *var;
920 u_int i, tmpenvsize = 0;
924 * We don't want to copy the whole file to the child's environment,
925 * so we use a temporary environment and copy the variables we're
928 read_environment_file(&tmpenv, &tmpenvsize, "/etc/default/login");
934 var = child_get_env(tmpenv, "SUPATH");
936 var = child_get_env(tmpenv, "PATH");
938 child_set_env(env, envsize, "PATH", var);
940 if ((var = child_get_env(tmpenv, "UMASK")) != NULL)
941 if (sscanf(var, "%5lo", &mask) == 1)
944 for (i = 0; tmpenv[i] != NULL; i++)
948 #endif /* HAVE_ETC_DEFAULT_LOGIN */
951 copy_environment(char **source, char ***env, u_int *envsize)
953 char *var_name, *var_val;
959 for(i = 0; source[i] != NULL; i++) {
960 var_name = xstrdup(source[i]);
961 if ((var_val = strstr(var_name, "=")) == NULL) {
967 debug3("Copy environment: %s=%s", var_name, var_val);
968 child_set_env(env, envsize, var_name, var_val);
975 do_setup_env(Session *s, const char *shell)
979 char **env, *laddr, *path = NULL;
980 struct passwd *pw = s->pw;
982 /* Initialize the environment. */
984 env = xmalloc(envsize * sizeof(char *));
989 * The Windows environment contains some setting which are
990 * important for a running system. They must not be dropped.
995 p = fetch_windows_environment();
996 copy_environment(p, &env, &envsize);
997 free_windows_environment(p);
1002 /* Allow any GSSAPI methods that we've used to alter
1003 * the childs environment as they see fit
1005 ssh_gssapi_do_child(&env, &envsize);
1008 if (!options.use_login) {
1009 /* Set basic environment. */
1010 for (i = 0; i < s->num_env; i++)
1011 child_set_env(&env, &envsize, s->env[i].name,
1014 child_set_env(&env, &envsize, "USER", pw->pw_name);
1015 child_set_env(&env, &envsize, "LOGNAME", pw->pw_name);
1017 child_set_env(&env, &envsize, "LOGIN", pw->pw_name);
1019 child_set_env(&env, &envsize, "HOME", pw->pw_dir);
1020 #ifdef HAVE_LOGIN_CAP
1021 if (setusercontext(lc, pw, pw->pw_uid, LOGIN_SETPATH) < 0)
1022 child_set_env(&env, &envsize, "PATH", _PATH_STDPATH);
1024 child_set_env(&env, &envsize, "PATH", getenv("PATH"));
1025 #else /* HAVE_LOGIN_CAP */
1026 # ifndef HAVE_CYGWIN
1028 * There's no standard path on Windows. The path contains
1029 * important components pointing to the system directories,
1030 * needed for loading shared libraries. So the path better
1031 * remains intact here.
1033 # ifdef HAVE_ETC_DEFAULT_LOGIN
1034 read_etc_default_login(&env, &envsize, pw->pw_uid);
1035 path = child_get_env(env, "PATH");
1036 # endif /* HAVE_ETC_DEFAULT_LOGIN */
1037 if (path == NULL || *path == '\0') {
1038 child_set_env(&env, &envsize, "PATH",
1039 s->pw->pw_uid == 0 ?
1040 SUPERUSER_PATH : _PATH_STDPATH);
1042 # endif /* HAVE_CYGWIN */
1043 #endif /* HAVE_LOGIN_CAP */
1045 snprintf(buf, sizeof buf, "%.200s/%.50s",
1046 _PATH_MAILDIR, pw->pw_name);
1047 child_set_env(&env, &envsize, "MAIL", buf);
1049 /* Normal systems set SHELL by default. */
1050 child_set_env(&env, &envsize, "SHELL", shell);
1053 child_set_env(&env, &envsize, "TZ", getenv("TZ"));
1055 /* Set custom environment options from RSA authentication. */
1056 if (!options.use_login) {
1057 while (custom_environment) {
1058 struct envstring *ce = custom_environment;
1061 for (i = 0; str[i] != '=' && str[i]; i++)
1063 if (str[i] == '=') {
1065 child_set_env(&env, &envsize, str, str + i + 1);
1067 custom_environment = ce->next;
1073 /* SSH_CLIENT deprecated */
1074 snprintf(buf, sizeof buf, "%.50s %d %d",
1075 get_remote_ipaddr(), get_remote_port(), get_local_port());
1076 child_set_env(&env, &envsize, "SSH_CLIENT", buf);
1078 laddr = get_local_ipaddr(packet_get_connection_in());
1079 snprintf(buf, sizeof buf, "%.50s %d %.50s %d",
1080 get_remote_ipaddr(), get_remote_port(), laddr, get_local_port());
1082 child_set_env(&env, &envsize, "SSH_CONNECTION", buf);
1085 child_set_env(&env, &envsize, "SSH_TTY", s->tty);
1087 child_set_env(&env, &envsize, "TERM", s->term);
1089 child_set_env(&env, &envsize, "DISPLAY", s->display);
1090 if (original_command)
1091 child_set_env(&env, &envsize, "SSH_ORIGINAL_COMMAND",
1095 if (cray_tmpdir[0] != '\0')
1096 child_set_env(&env, &envsize, "TMPDIR", cray_tmpdir);
1097 #endif /* _UNICOS */
1100 * Since we clear KRB5CCNAME at startup, if it's set now then it
1101 * must have been set by a native authentication method (eg AIX or
1102 * SIA), so copy it to the child.
1107 if ((cp = getenv("KRB5CCNAME")) != NULL)
1108 child_set_env(&env, &envsize, "KRB5CCNAME", cp);
1115 if ((cp = getenv("AUTHSTATE")) != NULL)
1116 child_set_env(&env, &envsize, "AUTHSTATE", cp);
1117 read_environment_file(&env, &envsize, "/etc/environment");
1121 if (s->authctxt->krb5_ccname)
1122 child_set_env(&env, &envsize, "KRB5CCNAME",
1123 s->authctxt->krb5_ccname);
1127 * Pull in any environment variables that may have
1130 if (options.use_pam) {
1133 p = fetch_pam_child_environment();
1134 copy_environment(p, &env, &envsize);
1135 free_pam_environment(p);
1137 p = fetch_pam_environment();
1138 copy_environment(p, &env, &envsize);
1139 free_pam_environment(p);
1141 #endif /* USE_PAM */
1143 if (auth_sock_name != NULL)
1144 child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME,
1147 /* read $HOME/.ssh/environment. */
1148 if (options.permit_user_env && !options.use_login) {
1149 snprintf(buf, sizeof buf, "%.200s/.ssh/environment",
1150 strcmp(pw->pw_dir, "/") ? pw->pw_dir : "");
1151 read_environment_file(&env, &envsize, buf);
1154 /* dump the environment */
1155 fprintf(stderr, "Environment:\n");
1156 for (i = 0; env[i]; i++)
1157 fprintf(stderr, " %.200s\n", env[i]);
1163 * Run $HOME/.ssh/rc, /etc/ssh/sshrc, or xauth (whichever is found
1164 * first in this order).
1167 do_rc_files(Session *s, const char *shell)
1175 s->display != NULL && s->auth_proto != NULL && s->auth_data != NULL;
1177 /* ignore _PATH_SSH_USER_RC for subsystems */
1178 if (!s->is_subsystem && (stat(_PATH_SSH_USER_RC, &st) >= 0)) {
1179 snprintf(cmd, sizeof cmd, "%s -c '%s %s'",
1180 shell, _PATH_BSHELL, _PATH_SSH_USER_RC);
1182 fprintf(stderr, "Running %s\n", cmd);
1183 f = popen(cmd, "w");
1186 fprintf(f, "%s %s\n", s->auth_proto,
1190 fprintf(stderr, "Could not run %s\n",
1192 } else if (stat(_PATH_SSH_SYSTEM_RC, &st) >= 0) {
1194 fprintf(stderr, "Running %s %s\n", _PATH_BSHELL,
1195 _PATH_SSH_SYSTEM_RC);
1196 f = popen(_PATH_BSHELL " " _PATH_SSH_SYSTEM_RC, "w");
1199 fprintf(f, "%s %s\n", s->auth_proto,
1203 fprintf(stderr, "Could not run %s\n",
1204 _PATH_SSH_SYSTEM_RC);
1205 } else if (do_xauth && options.xauth_location != NULL) {
1206 /* Add authority data to .Xauthority if appropriate. */
1209 "Running %.500s remove %.100s\n",
1210 options.xauth_location, s->auth_display);
1212 "%.500s add %.100s %.100s %.100s\n",
1213 options.xauth_location, s->auth_display,
1214 s->auth_proto, s->auth_data);
1216 snprintf(cmd, sizeof cmd, "%s -q -",
1217 options.xauth_location);
1218 f = popen(cmd, "w");
1220 fprintf(f, "remove %s\n",
1222 fprintf(f, "add %s %s %s\n",
1223 s->auth_display, s->auth_proto,
1227 fprintf(stderr, "Could not run %s\n",
1234 do_nologin(struct passwd *pw)
1239 #ifdef HAVE_LOGIN_CAP
1240 if (!login_getcapbool(lc, "ignorenologin", 0) && pw->pw_uid)
1241 f = fopen(login_getcapstr(lc, "nologin", _PATH_NOLOGIN,
1242 _PATH_NOLOGIN), "r");
1245 f = fopen(_PATH_NOLOGIN, "r");
1248 /* /etc/nologin exists. Print its contents and exit. */
1249 logit("User %.100s not allowed because %s exists",
1250 pw->pw_name, _PATH_NOLOGIN);
1251 while (fgets(buf, sizeof(buf), f))
1259 /* Set login name, uid, gid, and groups. */
1261 do_setusercontext(struct passwd *pw)
1264 if (getuid() == 0 || geteuid() == 0)
1265 #endif /* HAVE_CYGWIN */
1268 #ifdef HAVE_SETPCRED
1269 if (setpcred(pw->pw_name, (char **)NULL) == -1)
1270 fatal("Failed to set process credentials");
1271 #endif /* HAVE_SETPCRED */
1272 #ifdef HAVE_LOGIN_CAP
1277 if (options.gss_authentication) {
1278 temporarily_use_uid(pw);
1279 ssh_gssapi_storecreds();
1284 if (options.use_pam) {
1288 # endif /* USE_PAM */
1289 if (setusercontext(lc, pw, pw->pw_uid,
1290 (LOGIN_SETALL & ~LOGIN_SETPATH)) < 0) {
1291 perror("unable to set user context");
1295 # if defined(HAVE_GETLUID) && defined(HAVE_SETLUID)
1296 /* Sets login uid for accounting */
1297 if (getluid() == -1 && setluid(pw->pw_uid) == -1)
1298 error("setluid: %s", strerror(errno));
1299 # endif /* defined(HAVE_GETLUID) && defined(HAVE_SETLUID) */
1301 if (setlogin(pw->pw_name) < 0)
1302 error("setlogin failed: %s", strerror(errno));
1303 if (setgid(pw->pw_gid) < 0) {
1307 /* Initialize the group list. */
1308 if (initgroups(pw->pw_name, pw->pw_gid) < 0) {
1309 perror("initgroups");
1314 if (options.gss_authentication) {
1315 temporarily_use_uid(pw);
1316 ssh_gssapi_storecreds();
1322 * PAM credentials may take the form of supplementary groups.
1323 * These will have been wiped by the above initgroups() call.
1324 * Reestablish them here.
1326 if (options.use_pam) {
1330 # endif /* USE_PAM */
1331 # if defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY)
1332 irix_setusercontext(pw);
1333 # endif /* defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) */
1337 #if defined(HAVE_LIBIAF) && !defined(BROKEN_LIBIAF)
1338 if (set_id(pw->pw_name) != 0) {
1341 #endif /* HAVE_LIBIAF && !BROKEN_LIBIAF */
1342 /* Permanently switch to the desired uid. */
1343 permanently_set_uid(pw);
1350 if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid)
1351 fatal("Failed to set uids to %u.", (u_int) pw->pw_uid);
1355 do_pwchange(Session *s)
1358 fprintf(stderr, "WARNING: Your password has expired.\n");
1359 if (s->ttyfd != -1) {
1361 "You must change your password now and login again!\n");
1362 #ifdef PASSWD_NEEDS_USERNAME
1363 execl(_PATH_PASSWD_PROG, "passwd", s->pw->pw_name,
1366 execl(_PATH_PASSWD_PROG, "passwd", (char *)NULL);
1371 "Password change required but no TTY available.\n");
1377 launch_login(struct passwd *pw, const char *hostname)
1379 /* Launch login(1). */
1381 execl(LOGIN_PROGRAM, "login", "-h", hostname,
1382 #ifdef xxxLOGIN_NEEDS_TERM
1383 (s->term ? s->term : "unknown"),
1384 #endif /* LOGIN_NEEDS_TERM */
1385 #ifdef LOGIN_NO_ENDOPT
1386 "-p", "-f", pw->pw_name, (char *)NULL);
1388 "-p", "-f", "--", pw->pw_name, (char *)NULL);
1391 /* Login couldn't be executed, die. */
1398 child_close_fds(void)
1402 if (packet_get_connection_in() == packet_get_connection_out())
1403 close(packet_get_connection_in());
1405 close(packet_get_connection_in());
1406 close(packet_get_connection_out());
1409 * Close all descriptors related to channels. They will still remain
1410 * open in the parent.
1412 /* XXX better use close-on-exec? -markus */
1413 channel_close_all();
1416 * Close any extra file descriptors. Note that there may still be
1417 * descriptors left by system functions. They will be closed later.
1422 * Close any extra open file descriptors so that we don\'t have them
1423 * hanging around in clients. Note that we want to do this after
1424 * initgroups, because at least on Solaris 2.3 it leaves file
1427 for (i = 3; i < 64; i++)
1432 * Performs common processing for the child, such as setting up the
1433 * environment, closing extra file descriptors, setting the user and group
1434 * ids, and executing the command or shell.
1437 do_child(Session *s, const char *command)
1439 extern char **environ;
1442 const char *shell, *shell0, *hostname = NULL;
1443 struct passwd *pw = s->pw;
1445 /* remove hostkey from the child's memory */
1446 destroy_sensitive_data();
1448 /* Force a password change */
1449 if (s->authctxt->force_pwchange) {
1450 do_setusercontext(pw);
1456 /* login(1) is only called if we execute the login shell */
1457 if (options.use_login && command != NULL)
1458 options.use_login = 0;
1461 cray_setup(pw->pw_uid, pw->pw_name, command);
1462 #endif /* _UNICOS */
1465 * Login(1) does this as well, and it needs uid 0 for the "-h"
1466 * switch, so we let login(1) to this for us.
1468 if (!options.use_login) {
1470 session_setup_sia(pw, s->ttyfd == -1 ? NULL : s->tty);
1471 if (!check_quietlogin(s, command))
1473 #else /* HAVE_OSF_SIA */
1475 do_setusercontext(pw);
1477 * PAM session modules in do_setusercontext may have
1478 * generated messages, so if this in an interactive
1479 * login then display them too.
1481 if (!check_quietlogin(s, command))
1483 #endif /* HAVE_OSF_SIA */
1487 if (options.use_pam && !options.use_login && !is_pam_session_open()) {
1488 debug3("PAM session not opened, exiting");
1495 * Get the shell from the password data. An empty shell field is
1496 * legal, and means /bin/sh.
1498 shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
1501 * Make sure $SHELL points to the shell from the password file,
1502 * even if shell is overridden from login.conf
1504 env = do_setup_env(s, shell);
1506 #ifdef HAVE_LOGIN_CAP
1507 shell = login_getcapstr(lc, "shell", (char *)shell, (char *)shell);
1510 /* we have to stash the hostname before we close our socket. */
1511 if (options.use_login)
1512 hostname = get_remote_name_or_ip(utmp_len,
1515 * Close the connection descriptors; note that this is the child, and
1516 * the server will still have the socket open, and it is important
1517 * that we do not shutdown it. Note that the descriptors cannot be
1518 * closed before building the environment, as we call
1519 * get_remote_ipaddr there.
1524 * Must take new environment into use so that .ssh/rc,
1525 * /etc/ssh/sshrc and xauth are run in the proper environment.
1529 #if defined(KRB5) && defined(USE_AFS)
1531 * At this point, we check to see if AFS is active and if we have
1532 * a valid Kerberos 5 TGT. If so, it seems like a good idea to see
1533 * if we can (and need to) extend the ticket into an AFS token. If
1534 * we don't do this, we run into potential problems if the user's
1535 * home directory is in AFS and it's not world-readable.
1538 if (options.kerberos_get_afs_token && k_hasafs() &&
1539 (s->authctxt->krb5_ctx != NULL)) {
1542 debug("Getting AFS token");
1546 if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0)
1547 krb5_afslog(s->authctxt->krb5_ctx,
1548 s->authctxt->krb5_fwd_ccache, cell, NULL);
1550 krb5_afslog_home(s->authctxt->krb5_ctx,
1551 s->authctxt->krb5_fwd_ccache, NULL, NULL, pw->pw_dir);
1555 /* Change current directory to the user\'s home directory. */
1556 if (chdir(pw->pw_dir) < 0) {
1557 fprintf(stderr, "Could not chdir to home directory %s: %s\n",
1558 pw->pw_dir, strerror(errno));
1559 #ifdef HAVE_LOGIN_CAP
1560 if (login_getcapbool(lc, "requirehome", 0))
1565 if (!options.use_login)
1566 do_rc_files(s, shell);
1568 /* restore SIGPIPE for child */
1569 signal(SIGPIPE, SIG_DFL);
1571 if (options.use_login) {
1572 launch_login(pw, hostname);
1576 /* Get the last component of the shell name. */
1577 if ((shell0 = strrchr(shell, '/')) != NULL)
1583 * If we have no command, execute the shell. In this case, the shell
1584 * name to be passed in argv[0] is preceded by '-' to indicate that
1585 * this is a login shell.
1590 /* Start the shell. Set initial character to '-'. */
1593 if (strlcpy(argv0 + 1, shell0, sizeof(argv0) - 1)
1594 >= sizeof(argv0) - 1) {
1600 /* Execute the shell. */
1603 execve(shell, argv, env);
1605 /* Executing the shell failed. */
1610 * Execute the command using the user's shell. This uses the -c
1611 * option to execute the command.
1613 argv[0] = (char *) shell0;
1615 argv[2] = (char *) command;
1617 execve(shell, argv, env);
1626 static int did_init = 0;
1628 debug("session_new: init");
1629 for (i = 0; i < MAX_SESSIONS; i++) {
1630 sessions[i].used = 0;
1634 for (i = 0; i < MAX_SESSIONS; i++) {
1635 Session *s = &sessions[i];
1637 memset(s, 0, sizeof(*s));
1643 s->x11_chanids = NULL;
1644 debug("session_new: session %d", i);
1655 for (i = 0; i < MAX_SESSIONS; i++) {
1656 Session *s = &sessions[i];
1657 debug("dump: used %d session %d %p channel %d pid %ld",
1667 session_open(Authctxt *authctxt, int chanid)
1669 Session *s = session_new();
1670 debug("session_open: channel %d", chanid);
1672 error("no more sessions");
1675 s->authctxt = authctxt;
1676 s->pw = authctxt->pw;
1677 if (s->pw == NULL || !authctxt->valid)
1678 fatal("no user for session %d", s->self);
1679 debug("session_open: session %d: link with channel %d", s->self, chanid);
1685 session_by_tty(char *tty)
1688 for (i = 0; i < MAX_SESSIONS; i++) {
1689 Session *s = &sessions[i];
1690 if (s->used && s->ttyfd != -1 && strcmp(s->tty, tty) == 0) {
1691 debug("session_by_tty: session %d tty %s", i, tty);
1695 debug("session_by_tty: unknown tty %.100s", tty);
1701 session_by_channel(int id)
1704 for (i = 0; i < MAX_SESSIONS; i++) {
1705 Session *s = &sessions[i];
1706 if (s->used && s->chanid == id) {
1707 debug("session_by_channel: session %d channel %d", i, id);
1711 debug("session_by_channel: unknown channel %d", id);
1717 session_by_x11_channel(int id)
1721 for (i = 0; i < MAX_SESSIONS; i++) {
1722 Session *s = &sessions[i];
1724 if (s->x11_chanids == NULL || !s->used)
1726 for (j = 0; s->x11_chanids[j] != -1; j++) {
1727 if (s->x11_chanids[j] == id) {
1728 debug("session_by_x11_channel: session %d "
1729 "channel %d", s->self, id);
1734 debug("session_by_x11_channel: unknown channel %d", id);
1740 session_by_pid(pid_t pid)
1743 debug("session_by_pid: pid %ld", (long)pid);
1744 for (i = 0; i < MAX_SESSIONS; i++) {
1745 Session *s = &sessions[i];
1746 if (s->used && s->pid == pid)
1749 error("session_by_pid: unknown pid %ld", (long)pid);
1755 session_window_change_req(Session *s)
1757 s->col = packet_get_int();
1758 s->row = packet_get_int();
1759 s->xpixel = packet_get_int();
1760 s->ypixel = packet_get_int();
1762 pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1767 session_pty_req(Session *s)
1773 debug("Allocating a pty not permitted for this authentication.");
1776 if (s->ttyfd != -1) {
1777 packet_disconnect("Protocol error: you already have a pty.");
1781 s->term = packet_get_string(&len);
1784 s->col = packet_get_int();
1785 s->row = packet_get_int();
1787 s->row = packet_get_int();
1788 s->col = packet_get_int();
1790 s->xpixel = packet_get_int();
1791 s->ypixel = packet_get_int();
1793 if (strcmp(s->term, "") == 0) {
1798 /* Allocate a pty and open it. */
1799 debug("Allocating pty.");
1800 if (!PRIVSEP(pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty)))) {
1806 error("session_pty_req: session %d alloc failed", s->self);
1809 debug("session_pty_req: session %d alloc %s", s->self, s->tty);
1811 /* for SSH1 the tty modes length is not given */
1813 n_bytes = packet_remaining();
1814 tty_parse_modes(s->ttyfd, &n_bytes);
1817 pty_setowner(s->pw, s->tty);
1819 /* Set window size from the packet. */
1820 pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1823 session_proctitle(s);
1828 session_subsystem_req(Session *s)
1833 char *cmd, *subsys = packet_get_string(&len);
1837 logit("subsystem request for %.100s", subsys);
1839 for (i = 0; i < options.num_subsystems; i++) {
1840 if (strcmp(subsys, options.subsystem_name[i]) == 0) {
1841 cmd = options.subsystem_command[i];
1842 if (stat(cmd, &st) < 0) {
1843 error("subsystem: cannot stat %s: %s", cmd,
1847 debug("subsystem: exec() %s", cmd);
1848 s->is_subsystem = 1;
1856 logit("subsystem request for %.100s failed, subsystem not found",
1864 session_x11_req(Session *s)
1868 if (s->auth_proto != NULL || s->auth_data != NULL) {
1869 error("session_x11_req: session %d: "
1870 "x11 fowarding already active", s->self);
1873 s->single_connection = packet_get_char();
1874 s->auth_proto = packet_get_string(NULL);
1875 s->auth_data = packet_get_string(NULL);
1876 s->screen = packet_get_int();
1879 success = session_setup_x11fwd(s);
1881 xfree(s->auth_proto);
1882 xfree(s->auth_data);
1883 s->auth_proto = NULL;
1884 s->auth_data = NULL;
1890 session_shell_req(Session *s)
1898 session_exec_req(Session *s)
1901 char *command = packet_get_string(&len);
1903 do_exec(s, command);
1909 session_break_req(Session *s)
1912 packet_get_int(); /* ignored */
1915 if (s->ttyfd == -1 ||
1916 tcsendbreak(s->ttyfd, 0) < 0)
1922 session_env_req(Session *s)
1925 u_int name_len, val_len, i;
1927 name = packet_get_string(&name_len);
1928 val = packet_get_string(&val_len);
1931 /* Don't set too many environment variables */
1932 if (s->num_env > 128) {
1933 debug2("Ignoring env request %s: too many env vars", name);
1937 for (i = 0; i < options.num_accept_env; i++) {
1938 if (match_pattern(name, options.accept_env[i])) {
1939 debug2("Setting env %d: %s=%s", s->num_env, name, val);
1940 s->env = xrealloc(s->env, sizeof(*s->env) *
1942 s->env[s->num_env].name = name;
1943 s->env[s->num_env].val = val;
1948 debug2("Ignoring env request %s: disallowed name", name);
1957 session_auth_agent_req(Session *s)
1959 static int called = 0;
1961 if (no_agent_forwarding_flag) {
1962 debug("session_auth_agent_req: no_agent_forwarding_flag");
1969 return auth_input_request_forwarding(s->pw);
1974 session_input_channel_req(Channel *c, const char *rtype)
1979 if ((s = session_by_channel(c->self)) == NULL) {
1980 logit("session_input_channel_req: no session %d req %.100s",
1984 debug("session_input_channel_req: session %d req %s", s->self, rtype);
1987 * a session is in LARVAL state until a shell, a command
1988 * or a subsystem is executed
1990 if (c->type == SSH_CHANNEL_LARVAL) {
1991 if (strcmp(rtype, "shell") == 0) {
1992 success = session_shell_req(s);
1993 } else if (strcmp(rtype, "exec") == 0) {
1994 success = session_exec_req(s);
1995 } else if (strcmp(rtype, "pty-req") == 0) {
1996 success = session_pty_req(s);
1997 } else if (strcmp(rtype, "x11-req") == 0) {
1998 success = session_x11_req(s);
1999 } else if (strcmp(rtype, "auth-agent-req@openssh.com") == 0) {
2000 success = session_auth_agent_req(s);
2001 } else if (strcmp(rtype, "subsystem") == 0) {
2002 success = session_subsystem_req(s);
2003 } else if (strcmp(rtype, "env") == 0) {
2004 success = session_env_req(s);
2007 if (strcmp(rtype, "window-change") == 0) {
2008 success = session_window_change_req(s);
2009 } else if (strcmp(rtype, "break") == 0) {
2010 success = session_break_req(s);
2017 session_set_fds(Session *s, int fdin, int fdout, int fderr)
2020 fatal("session_set_fds: called for proto != 2.0");
2022 * now that have a child and a pipe to the child,
2023 * we can activate our channel and register the fd's
2025 if (s->chanid == -1)
2026 fatal("no channel for session %d", s->self);
2027 channel_set_fds(s->chanid,
2029 fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ,
2031 CHAN_SES_WINDOW_DEFAULT);
2035 * Function to perform pty cleanup. Also called if we get aborted abnormally
2036 * (e.g., due to a dropped connection).
2039 session_pty_cleanup2(Session *s)
2042 error("session_pty_cleanup: no session");
2048 debug("session_pty_cleanup: session %d release %s", s->self, s->tty);
2050 /* Record that the user has logged out. */
2052 record_logout(s->pid, s->tty, s->pw->pw_name);
2054 /* Release the pseudo-tty. */
2056 pty_release(s->tty);
2059 * Close the server side of the socket pairs. We must do this after
2060 * the pty cleanup, so that another process doesn't get this pty
2061 * while we're still cleaning up.
2063 if (close(s->ptymaster) < 0)
2064 error("close(s->ptymaster/%d): %s", s->ptymaster, strerror(errno));
2066 /* unlink pty from session */
2071 session_pty_cleanup(Session *s)
2073 PRIVSEP(session_pty_cleanup2(s));
2079 #define SSH_SIG(x) if (sig == SIG ## x) return #x
2094 return "SIG@openssh.com";
2098 session_close_x11(int id)
2102 if ((c = channel_lookup(id)) == NULL) {
2103 debug("session_close_x11: x11 channel %d missing", id);
2105 /* Detach X11 listener */
2106 debug("session_close_x11: detach x11 channel %d", id);
2107 channel_cancel_cleanup(id);
2108 if (c->ostate != CHAN_OUTPUT_CLOSED)
2114 session_close_single_x11(int id, void *arg)
2119 debug3("session_close_single_x11: channel %d", id);
2120 channel_cancel_cleanup(id);
2121 if ((s = session_by_x11_channel(id)) == NULL)
2122 fatal("session_close_single_x11: no x11 channel %d", id);
2123 for (i = 0; s->x11_chanids[i] != -1; i++) {
2124 debug("session_close_single_x11: session %d: "
2125 "closing channel %d", s->self, s->x11_chanids[i]);
2127 * The channel "id" is already closing, but make sure we
2128 * close all of its siblings.
2130 if (s->x11_chanids[i] != id)
2131 session_close_x11(s->x11_chanids[i]);
2133 xfree(s->x11_chanids);
2134 s->x11_chanids = NULL;
2139 if (s->auth_proto) {
2140 xfree(s->auth_proto);
2141 s->auth_proto = NULL;
2144 xfree(s->auth_data);
2145 s->auth_data = NULL;
2147 if (s->auth_display) {
2148 xfree(s->auth_display);
2149 s->auth_display = NULL;
2154 session_exit_message(Session *s, int status)
2159 if ((c = channel_lookup(s->chanid)) == NULL)
2160 fatal("session_exit_message: session %d: no channel %d",
2161 s->self, s->chanid);
2162 debug("session_exit_message: session %d channel %d pid %ld",
2163 s->self, s->chanid, (long)s->pid);
2165 if (WIFEXITED(status)) {
2166 channel_request_start(s->chanid, "exit-status", 0);
2167 packet_put_int(WEXITSTATUS(status));
2169 } else if (WIFSIGNALED(status)) {
2170 channel_request_start(s->chanid, "exit-signal", 0);
2171 packet_put_cstring(sig2name(WTERMSIG(status)));
2173 packet_put_char(WCOREDUMP(status));
2174 #else /* WCOREDUMP */
2176 #endif /* WCOREDUMP */
2177 packet_put_cstring("");
2178 packet_put_cstring("");
2181 /* Some weird exit cause. Just exit. */
2182 packet_disconnect("wait returned status %04x.", status);
2185 /* disconnect channel */
2186 debug("session_exit_message: release channel %d", s->chanid);
2187 channel_cancel_cleanup(s->chanid);
2189 * emulate a write failure with 'chan_write_failed', nobody will be
2190 * interested in data we write.
2191 * Note that we must not call 'chan_read_failed', since there could
2192 * be some more data waiting in the pipe.
2194 if (c->ostate != CHAN_OUTPUT_CLOSED)
2195 chan_write_failed(c);
2198 /* Close any X11 listeners associated with this session */
2199 if (s->x11_chanids != NULL) {
2200 for (i = 0; s->x11_chanids[i] != -1; i++) {
2201 session_close_x11(s->x11_chanids[i]);
2202 s->x11_chanids[i] = -1;
2208 session_close(Session *s)
2212 debug("session_close: session %d pid %ld", s->self, (long)s->pid);
2214 session_pty_cleanup(s);
2220 xfree(s->x11_chanids);
2221 if (s->auth_display)
2222 xfree(s->auth_display);
2224 xfree(s->auth_data);
2226 xfree(s->auth_proto);
2228 for (i = 0; i < s->num_env; i++) {
2229 xfree(s->env[i].name);
2230 xfree(s->env[i].val);
2234 session_proctitle(s);
2238 session_close_by_pid(pid_t pid, int status)
2240 Session *s = session_by_pid(pid);
2242 debug("session_close_by_pid: no session for pid %ld",
2246 if (s->chanid != -1)
2247 session_exit_message(s, status);
2252 * this is called when a channel dies before
2253 * the session 'child' itself dies
2256 session_close_by_channel(int id, void *arg)
2258 Session *s = session_by_channel(id);
2261 debug("session_close_by_channel: no session for id %d", id);
2264 debug("session_close_by_channel: channel %d child %ld",
2267 debug("session_close_by_channel: channel %d: has child", id);
2269 * delay detach of session, but release pty, since
2270 * the fd's to the child are already closed
2273 session_pty_cleanup(s);
2276 /* detach by removing callback */
2277 channel_cancel_cleanup(s->chanid);
2283 session_destroy_all(void (*closefunc)(Session *))
2286 for (i = 0; i < MAX_SESSIONS; i++) {
2287 Session *s = &sessions[i];
2289 if (closefunc != NULL)
2298 session_tty_list(void)
2300 static char buf[1024];
2305 for (i = 0; i < MAX_SESSIONS; i++) {
2306 Session *s = &sessions[i];
2307 if (s->used && s->ttyfd != -1) {
2309 if (strncmp(s->tty, "/dev/", 5) != 0) {
2310 cp = strrchr(s->tty, '/');
2311 cp = (cp == NULL) ? s->tty : cp + 1;
2316 strlcat(buf, ",", sizeof buf);
2317 strlcat(buf, cp, sizeof buf);
2321 strlcpy(buf, "notty", sizeof buf);
2326 session_proctitle(Session *s)
2329 error("no user for session %d", s->self);
2331 setproctitle("%s@%s", s->pw->pw_name, session_tty_list());
2335 session_setup_x11fwd(Session *s)
2338 char display[512], auth_display[512];
2339 char hostname[MAXHOSTNAMELEN];
2342 if (no_x11_forwarding_flag) {
2343 packet_send_debug("X11 forwarding disabled in user configuration file.");
2346 if (!options.x11_forwarding) {
2347 debug("X11 forwarding disabled in server configuration file.");
2350 if (!options.xauth_location ||
2351 (stat(options.xauth_location, &st) == -1)) {
2352 packet_send_debug("No xauth program; cannot forward with spoofing.");
2355 if (options.use_login) {
2356 packet_send_debug("X11 forwarding disabled; "
2357 "not compatible with UseLogin=yes.");
2360 if (s->display != NULL) {
2361 debug("X11 display already set.");
2364 if (x11_create_display_inet(options.x11_display_offset,
2365 options.x11_use_localhost, s->single_connection,
2366 &s->display_number, &s->x11_chanids) == -1) {
2367 debug("x11_create_display_inet failed.");
2370 for (i = 0; s->x11_chanids[i] != -1; i++) {
2371 channel_register_cleanup(s->x11_chanids[i],
2372 session_close_single_x11);
2375 /* Set up a suitable value for the DISPLAY variable. */
2376 if (gethostname(hostname, sizeof(hostname)) < 0)
2377 fatal("gethostname: %.100s", strerror(errno));
2379 * auth_display must be used as the displayname when the
2380 * authorization entry is added with xauth(1). This will be
2381 * different than the DISPLAY string for localhost displays.
2383 if (options.x11_use_localhost) {
2384 snprintf(display, sizeof display, "localhost:%u.%u",
2385 s->display_number, s->screen);
2386 snprintf(auth_display, sizeof auth_display, "unix:%u.%u",
2387 s->display_number, s->screen);
2388 s->display = xstrdup(display);
2389 s->auth_display = xstrdup(auth_display);
2391 #ifdef IPADDR_IN_DISPLAY
2393 struct in_addr my_addr;
2395 he = gethostbyname(hostname);
2397 error("Can't get IP address for X11 DISPLAY.");
2398 packet_send_debug("Can't get IP address for X11 DISPLAY.");
2401 memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr));
2402 snprintf(display, sizeof display, "%.50s:%u.%u", inet_ntoa(my_addr),
2403 s->display_number, s->screen);
2405 snprintf(display, sizeof display, "%.400s:%u.%u", hostname,
2406 s->display_number, s->screen);
2408 s->display = xstrdup(display);
2409 s->auth_display = xstrdup(display);
2416 do_authenticated2(Authctxt *authctxt)
2418 server_loop2(authctxt);
2422 do_cleanup(Authctxt *authctxt)
2424 static int called = 0;
2426 debug("do_cleanup");
2428 /* no cleanup if we're in the child for login shell */
2432 /* avoid double cleanup */
2437 if (authctxt == NULL)
2440 if (options.kerberos_ticket_cleanup &&
2442 krb5_cleanup_proc(authctxt);
2446 if (compat20 && options.gss_cleanup_creds)
2447 ssh_gssapi_cleanup_creds();
2451 if (options.use_pam) {
2453 sshpam_thread_cleanup();
2457 /* remove agent socket */
2458 auth_sock_cleanup_proc(authctxt->pw);
2461 * Cleanup ptys/utmp only if privsep is disabled,
2462 * or if running in monitor.
2464 if (!use_privsep || mm_is_monitor())
2465 session_destroy_all(session_pty_cleanup2);