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 1.192 2006/02/08 12:15:27 stevesk Exp $");
53 #include "auth-options.h"
54 #include "pathnames.h"
58 #include "serverloop.h"
62 #include "monitor_wrap.h"
64 #if defined(KRB5) && defined(USE_AFS)
74 Session *session_new(void);
75 void session_set_fds(Session *, int, int, int);
76 void session_pty_cleanup(Session *);
77 void session_proctitle(Session *);
78 int session_setup_x11fwd(Session *);
79 void do_exec_pty(Session *, const char *);
80 void do_exec_no_pty(Session *, const char *);
81 void do_exec(Session *, const char *);
82 void do_login(Session *, const char *);
83 #ifdef LOGIN_NEEDS_UTMPX
84 static void do_pre_login(Session *s);
86 void do_child(Session *, const char *);
88 int check_quietlogin(Session *, const char *);
90 static void do_authenticated1(Authctxt *);
91 static void do_authenticated2(Authctxt *);
93 static int session_pty_req(Session *);
96 extern ServerOptions options;
97 extern char *__progname;
98 extern int log_stderr;
99 extern int debug_flag;
100 extern u_int utmp_len;
101 extern int startup_pipe;
102 extern void destroy_sensitive_data(void);
103 extern Buffer loginmsg;
105 /* original command from peer. */
106 const char *original_command = NULL;
109 #define MAX_SESSIONS 10
110 Session sessions[MAX_SESSIONS];
112 #ifdef HAVE_LOGIN_CAP
116 static int is_child = 0;
118 /* Name and directory of socket for authentication agent forwarding. */
119 static char *auth_sock_name = NULL;
120 static char *auth_sock_dir = NULL;
122 /* removes the agent forwarding socket */
125 auth_sock_cleanup_proc(struct passwd *pw)
127 if (auth_sock_name != NULL) {
128 temporarily_use_uid(pw);
129 unlink(auth_sock_name);
130 rmdir(auth_sock_dir);
131 auth_sock_name = NULL;
137 auth_input_request_forwarding(struct passwd * pw)
141 struct sockaddr_un sunaddr;
143 if (auth_sock_name != NULL) {
144 error("authentication forwarding requested twice.");
148 /* Temporarily drop privileged uid for mkdir/bind. */
149 temporarily_use_uid(pw);
151 /* Allocate a buffer for the socket name, and format the name. */
152 auth_sock_name = xmalloc(MAXPATHLEN);
153 auth_sock_dir = xmalloc(MAXPATHLEN);
154 strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN);
156 /* Create private directory for socket */
157 if (mkdtemp(auth_sock_dir) == NULL) {
158 packet_send_debug("Agent forwarding disabled: "
159 "mkdtemp() failed: %.100s", strerror(errno));
161 xfree(auth_sock_name);
162 xfree(auth_sock_dir);
163 auth_sock_name = NULL;
164 auth_sock_dir = NULL;
167 snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%ld",
168 auth_sock_dir, (long) getpid());
170 /* Create the socket. */
171 sock = socket(AF_UNIX, SOCK_STREAM, 0);
173 packet_disconnect("socket: %.100s", strerror(errno));
175 /* Bind it to the name. */
176 memset(&sunaddr, 0, sizeof(sunaddr));
177 sunaddr.sun_family = AF_UNIX;
178 strlcpy(sunaddr.sun_path, auth_sock_name, sizeof(sunaddr.sun_path));
180 if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0)
181 packet_disconnect("bind: %.100s", strerror(errno));
183 /* Restore the privileged uid. */
186 /* Start listening on the socket. */
187 if (listen(sock, SSH_LISTEN_BACKLOG) < 0)
188 packet_disconnect("listen: %.100s", strerror(errno));
190 /* Allocate a channel for the authentication agent socket. */
191 nc = channel_new("auth socket",
192 SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1,
193 CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
194 0, "auth socket", 1);
195 strlcpy(nc->path, auth_sock_name, sizeof(nc->path));
200 display_loginmsg(void)
202 if (buffer_len(&loginmsg) > 0) {
203 buffer_append(&loginmsg, "\0", 1);
204 printf("%s", (char *)buffer_ptr(&loginmsg));
205 buffer_clear(&loginmsg);
210 do_authenticated(Authctxt *authctxt)
212 setproctitle("%s", authctxt->pw->pw_name);
214 /* setup the channel layer */
215 if (!no_port_forwarding_flag && options.allow_tcp_forwarding)
216 channel_permit_all_opens();
219 do_authenticated2(authctxt);
221 do_authenticated1(authctxt);
223 do_cleanup(authctxt);
227 * Prepares for an interactive session. This is called after the user has
228 * been successfully authenticated. During this message exchange, pseudo
229 * terminals are allocated, X11, TCP/IP, and authentication agent forwardings
230 * are requested, etc.
233 do_authenticated1(Authctxt *authctxt)
237 int success, type, screen_flag;
238 int enable_compression_after_reply = 0;
239 u_int proto_len, data_len, dlen, compression_level = 0;
243 error("no more sessions");
246 s->authctxt = authctxt;
247 s->pw = authctxt->pw;
250 * We stay in this loop until the client requests to execute a shell
256 /* Get a packet from the client. */
257 type = packet_read();
259 /* Process the packet. */
261 case SSH_CMSG_REQUEST_COMPRESSION:
262 compression_level = packet_get_int();
264 if (compression_level < 1 || compression_level > 9) {
265 packet_send_debug("Received invalid compression level %d.",
269 if (options.compression == COMP_NONE) {
270 debug2("compression disabled");
273 /* Enable compression after we have responded with SUCCESS. */
274 enable_compression_after_reply = 1;
278 case SSH_CMSG_REQUEST_PTY:
279 success = session_pty_req(s);
282 case SSH_CMSG_X11_REQUEST_FORWARDING:
283 s->auth_proto = packet_get_string(&proto_len);
284 s->auth_data = packet_get_string(&data_len);
286 screen_flag = packet_get_protocol_flags() &
287 SSH_PROTOFLAG_SCREEN_NUMBER;
288 debug2("SSH_PROTOFLAG_SCREEN_NUMBER: %d", screen_flag);
290 if (packet_remaining() == 4) {
292 debug2("Buggy client: "
293 "X11 screen flag missing");
294 s->screen = packet_get_int();
299 success = session_setup_x11fwd(s);
301 xfree(s->auth_proto);
303 s->auth_proto = NULL;
308 case SSH_CMSG_AGENT_REQUEST_FORWARDING:
309 if (no_agent_forwarding_flag || compat13) {
310 debug("Authentication agent forwarding not permitted for this authentication.");
313 debug("Received authentication agent forwarding request.");
314 success = auth_input_request_forwarding(s->pw);
317 case SSH_CMSG_PORT_FORWARD_REQUEST:
318 if (no_port_forwarding_flag) {
319 debug("Port forwarding not permitted for this authentication.");
322 if (!options.allow_tcp_forwarding) {
323 debug("Port forwarding not permitted.");
326 debug("Received TCP/IP port forwarding request.");
327 channel_input_port_forward_request(s->pw->pw_uid == 0, options.gateway_ports);
331 case SSH_CMSG_MAX_PACKET_SIZE:
332 if (packet_set_maxsize(packet_get_int()) > 0)
336 case SSH_CMSG_EXEC_SHELL:
337 case SSH_CMSG_EXEC_CMD:
338 if (type == SSH_CMSG_EXEC_CMD) {
339 command = packet_get_string(&dlen);
340 debug("Exec command '%.500s'", command);
352 * Any unknown messages in this phase are ignored,
353 * and a failure message is returned.
355 logit("Unknown packet type received after authentication: %d", type);
357 packet_start(success ? SSH_SMSG_SUCCESS : SSH_SMSG_FAILURE);
361 /* Enable compression now that we have replied if appropriate. */
362 if (enable_compression_after_reply) {
363 enable_compression_after_reply = 0;
364 packet_start_compression(compression_level);
370 * This is called to fork and execute a command when we have no tty. This
371 * will call do_child from the child, and server_loop from the parent after
372 * setting up file descriptors and such.
375 do_exec_no_pty(Session *s, const char *command)
380 int pin[2], pout[2], perr[2];
381 /* Allocate pipes for communicating with the program. */
382 if (pipe(pin) < 0 || pipe(pout) < 0 || pipe(perr) < 0)
383 packet_disconnect("Could not create pipes: %.100s",
385 #else /* USE_PIPES */
386 int inout[2], err[2];
387 /* Uses socket pairs to communicate with the program. */
388 if (socketpair(AF_UNIX, SOCK_STREAM, 0, inout) < 0 ||
389 socketpair(AF_UNIX, SOCK_STREAM, 0, err) < 0)
390 packet_disconnect("Could not create socket pairs: %.100s",
392 #endif /* USE_PIPES */
394 fatal("do_exec_no_pty: no session");
396 session_proctitle(s);
399 if (options.use_pam && !use_privsep)
403 /* Fork the child. */
404 if ((pid = fork()) == 0) {
407 /* Child. Reinitialize the log since the pid has changed. */
408 log_init(__progname, options.log_level, options.log_facility, log_stderr);
411 * Create a new session and process group since the 4.4BSD
412 * setlogin() affects the entire process group.
415 error("setsid failed: %.100s", strerror(errno));
419 * Redirect stdin. We close the parent side of the socket
420 * pair, and make the child side the standard input.
423 if (dup2(pin[0], 0) < 0)
424 perror("dup2 stdin");
427 /* Redirect stdout. */
429 if (dup2(pout[1], 1) < 0)
430 perror("dup2 stdout");
433 /* Redirect stderr. */
435 if (dup2(perr[1], 2) < 0)
436 perror("dup2 stderr");
438 #else /* USE_PIPES */
440 * Redirect stdin, stdout, and stderr. Stdin and stdout will
441 * use the same socket, as some programs (particularly rdist)
442 * seem to depend on it.
446 if (dup2(inout[0], 0) < 0) /* stdin */
447 perror("dup2 stdin");
448 if (dup2(inout[0], 1) < 0) /* stdout. Note: same socket as stdin. */
449 perror("dup2 stdout");
450 if (dup2(err[0], 2) < 0) /* stderr */
451 perror("dup2 stderr");
452 #endif /* USE_PIPES */
455 cray_init_job(s->pw); /* set up cray jid and tmpdir */
458 /* Do processing for the child (exec command etc). */
459 do_child(s, command);
463 signal(WJSIGNAL, cray_job_termination_handler);
467 cygwin_set_impersonation_token(INVALID_HANDLE_VALUE);
470 packet_disconnect("fork failed: %.100s", strerror(errno));
472 /* Set interactive/non-interactive mode. */
473 packet_set_interactive(s->display != NULL);
475 /* We are the parent. Close the child sides of the pipes. */
481 if (s->is_subsystem) {
485 session_set_fds(s, pin[1], pout[0], perr[0]);
487 /* Enter the interactive session. */
488 server_loop(pid, pin[1], pout[0], perr[0]);
489 /* server_loop has closed pin[1], pout[0], and perr[0]. */
491 #else /* USE_PIPES */
492 /* We are the parent. Close the child sides of the socket pairs. */
497 * Clear loginmsg, since it's the child's responsibility to display
498 * it to the user, otherwise multiple sessions may accumulate
499 * multiple copies of the login messages.
501 buffer_clear(&loginmsg);
504 * Enter the interactive session. Note: server_loop must be able to
505 * handle the case that fdin and fdout are the same.
508 session_set_fds(s, inout[1], inout[1], s->is_subsystem ? -1 : err[1]);
510 server_loop(pid, inout[1], inout[1], err[1]);
511 /* server_loop has closed inout[1] and err[1]. */
513 #endif /* USE_PIPES */
517 * This is called to fork and execute a command when we have a tty. This
518 * will call do_child from the child, and server_loop from the parent after
519 * setting up file descriptors, controlling tty, updating wtmp, utmp,
520 * lastlog, and other such operations.
523 do_exec_pty(Session *s, const char *command)
525 int fdout, ptyfd, ttyfd, ptymaster;
529 fatal("do_exec_pty: no session");
534 if (options.use_pam) {
535 do_pam_set_tty(s->tty);
541 /* Fork the child. */
542 if ((pid = fork()) == 0) {
545 /* Child. Reinitialize the log because the pid has changed. */
546 log_init(__progname, options.log_level, options.log_facility, log_stderr);
547 /* Close the master side of the pseudo tty. */
550 /* Make the pseudo tty our controlling tty. */
551 pty_make_controlling_tty(&ttyfd, s->tty);
553 /* Redirect stdin/stdout/stderr from the pseudo tty. */
554 if (dup2(ttyfd, 0) < 0)
555 error("dup2 stdin: %s", strerror(errno));
556 if (dup2(ttyfd, 1) < 0)
557 error("dup2 stdout: %s", strerror(errno));
558 if (dup2(ttyfd, 2) < 0)
559 error("dup2 stderr: %s", strerror(errno));
561 /* Close the extra descriptor for the pseudo tty. */
564 /* record login, etc. similar to login(1) */
566 if (!(options.use_login && command == NULL)) {
568 cray_init_job(s->pw); /* set up cray jid and tmpdir */
570 do_login(s, command);
572 # ifdef LOGIN_NEEDS_UTMPX
578 /* Do common processing for the child, such as execing the command. */
579 do_child(s, command);
583 signal(WJSIGNAL, cray_job_termination_handler);
587 cygwin_set_impersonation_token(INVALID_HANDLE_VALUE);
590 packet_disconnect("fork failed: %.100s", strerror(errno));
593 /* Parent. Close the slave side of the pseudo tty. */
597 * Create another descriptor of the pty master side for use as the
598 * standard input. We could use the original descriptor, but this
599 * simplifies code in server_loop. The descriptor is bidirectional.
603 packet_disconnect("dup #1 failed: %.100s", strerror(errno));
605 /* we keep a reference to the pty master */
606 ptymaster = dup(ptyfd);
608 packet_disconnect("dup #2 failed: %.100s", strerror(errno));
609 s->ptymaster = ptymaster;
611 /* Enter interactive session. */
612 packet_set_interactive(1);
614 session_set_fds(s, ptyfd, fdout, -1);
616 server_loop(pid, ptyfd, fdout, -1);
617 /* server_loop _has_ closed ptyfd and fdout. */
621 #ifdef LOGIN_NEEDS_UTMPX
623 do_pre_login(Session *s)
626 struct sockaddr_storage from;
627 pid_t pid = getpid();
630 * Get IP address of client. If the connection is not a socket, let
631 * the address be 0.0.0.0.
633 memset(&from, 0, sizeof(from));
634 fromlen = sizeof(from);
635 if (packet_connection_is_on_socket()) {
636 if (getpeername(packet_get_connection_in(),
637 (struct sockaddr *) & from, &fromlen) < 0) {
638 debug("getpeername: %.100s", strerror(errno));
643 record_utmp_only(pid, s->tty, s->pw->pw_name,
644 get_remote_name_or_ip(utmp_len, options.use_dns),
645 (struct sockaddr *)&from, fromlen);
650 * This is called to fork and execute a command. If another command is
651 * to be forced, execute that instead.
654 do_exec(Session *s, const char *command)
656 if (forced_command) {
657 original_command = command;
658 command = forced_command;
659 debug("Forced command '%.900s'", command);
662 #ifdef SSH_AUDIT_EVENTS
664 PRIVSEP(audit_run_command(command));
665 else if (s->ttyfd == -1) {
666 char *shell = s->pw->pw_shell;
668 if (shell[0] == '\0') /* empty shell means /bin/sh */
670 PRIVSEP(audit_run_command(shell));
675 do_exec_pty(s, command);
677 do_exec_no_pty(s, command);
679 original_command = NULL;
682 * Clear loginmsg: it's the child's responsibility to display
683 * it to the user, otherwise multiple sessions may accumulate
684 * multiple copies of the login messages.
686 buffer_clear(&loginmsg);
689 /* administrative, login(1)-like work */
691 do_login(Session *s, const char *command)
694 struct sockaddr_storage from;
695 struct passwd * pw = s->pw;
696 pid_t pid = getpid();
699 * Get IP address of client. If the connection is not a socket, let
700 * the address be 0.0.0.0.
702 memset(&from, 0, sizeof(from));
703 fromlen = sizeof(from);
704 if (packet_connection_is_on_socket()) {
705 if (getpeername(packet_get_connection_in(),
706 (struct sockaddr *) & from, &fromlen) < 0) {
707 debug("getpeername: %.100s", strerror(errno));
712 /* Record that there was a login on that tty from the remote host. */
714 record_login(pid, s->tty, pw->pw_name, pw->pw_uid,
715 get_remote_name_or_ip(utmp_len,
717 (struct sockaddr *)&from, fromlen);
721 * If password change is needed, do it now.
722 * This needs to occur before the ~/.hushlogin check.
724 if (options.use_pam && !use_privsep && s->authctxt->force_pwchange) {
727 s->authctxt->force_pwchange = 0;
728 /* XXX - signal [net] parent to enable forwardings */
732 if (check_quietlogin(s, command))
741 * Display the message of the day.
749 if (options.print_motd) {
750 #ifdef HAVE_LOGIN_CAP
751 f = fopen(login_getcapstr(lc, "welcome", "/etc/motd",
754 f = fopen("/etc/motd", "r");
757 while (fgets(buf, sizeof(buf), f))
766 * Check for quiet login, either .hushlogin or command given.
769 check_quietlogin(Session *s, const char *command)
772 struct passwd *pw = s->pw;
775 /* Return 1 if .hushlogin exists or a command given. */
778 snprintf(buf, sizeof(buf), "%.200s/.hushlogin", pw->pw_dir);
779 #ifdef HAVE_LOGIN_CAP
780 if (login_getcapbool(lc, "hushlogin", 0) || stat(buf, &st) >= 0)
783 if (stat(buf, &st) >= 0)
790 * Sets the value of the given variable in the environment. If the variable
791 * already exists, its value is overriden.
794 child_set_env(char ***envp, u_int *envsizep, const char *name,
802 * If we're passed an uninitialized list, allocate a single null
803 * entry before continuing.
805 if (*envp == NULL && *envsizep == 0) {
806 *envp = xmalloc(sizeof(char *));
812 * Find the slot where the value should be stored. If the variable
813 * already exists, we reuse the slot; otherwise we append a new slot
814 * at the end of the array, expanding if necessary.
817 namelen = strlen(name);
818 for (i = 0; env[i]; i++)
819 if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=')
822 /* Reuse the slot. */
825 /* New variable. Expand if necessary. */
827 if (i >= envsize - 1) {
829 fatal("child_set_env: too many env vars");
831 env = (*envp) = xrealloc(env, envsize * sizeof(char *));
834 /* Need to set the NULL pointer at end of array beyond the new slot. */
838 /* Allocate space and format the variable in the appropriate slot. */
839 env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1);
840 snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value);
844 * Reads environment variables from the given file and adds/overrides them
845 * into the environment. If the file does not exist, this does nothing.
846 * Otherwise, it must consist of empty lines, comments (line starts with '#')
847 * and assignments of the form name=value. No other forms are allowed.
850 read_environment_file(char ***env, u_int *envsize,
851 const char *filename)
858 f = fopen(filename, "r");
862 while (fgets(buf, sizeof(buf), f)) {
864 fatal("Too many lines in environment file %s", filename);
865 for (cp = buf; *cp == ' ' || *cp == '\t'; cp++)
867 if (!*cp || *cp == '#' || *cp == '\n')
869 if (strchr(cp, '\n'))
870 *strchr(cp, '\n') = '\0';
871 value = strchr(cp, '=');
873 fprintf(stderr, "Bad line %u in %.100s\n", lineno,
878 * Replace the equals sign by nul, and advance value to
883 child_set_env(env, envsize, cp, value);
888 #ifdef HAVE_ETC_DEFAULT_LOGIN
890 * Return named variable from specified environment, or NULL if not present.
893 child_get_env(char **env, const char *name)
899 for (i=0; env[i] != NULL; i++)
900 if (strncmp(name, env[i], len) == 0 && env[i][len] == '=')
901 return(env[i] + len + 1);
906 * Read /etc/default/login.
907 * We pick up the PATH (or SUPATH for root) and UMASK.
910 read_etc_default_login(char ***env, u_int *envsize, uid_t uid)
912 char **tmpenv = NULL, *var;
913 u_int i, tmpenvsize = 0;
917 * We don't want to copy the whole file to the child's environment,
918 * so we use a temporary environment and copy the variables we're
921 read_environment_file(&tmpenv, &tmpenvsize, "/etc/default/login");
927 var = child_get_env(tmpenv, "SUPATH");
929 var = child_get_env(tmpenv, "PATH");
931 child_set_env(env, envsize, "PATH", var);
933 if ((var = child_get_env(tmpenv, "UMASK")) != NULL)
934 if (sscanf(var, "%5lo", &mask) == 1)
937 for (i = 0; tmpenv[i] != NULL; i++)
941 #endif /* HAVE_ETC_DEFAULT_LOGIN */
944 copy_environment(char **source, char ***env, u_int *envsize)
946 char *var_name, *var_val;
952 for(i = 0; source[i] != NULL; i++) {
953 var_name = xstrdup(source[i]);
954 if ((var_val = strstr(var_name, "=")) == NULL) {
960 debug3("Copy environment: %s=%s", var_name, var_val);
961 child_set_env(env, envsize, var_name, var_val);
968 do_setup_env(Session *s, const char *shell)
972 char **env, *laddr, *path = NULL;
973 struct passwd *pw = s->pw;
975 /* Initialize the environment. */
977 env = xmalloc(envsize * sizeof(char *));
982 * The Windows environment contains some setting which are
983 * important for a running system. They must not be dropped.
988 p = fetch_windows_environment();
989 copy_environment(p, &env, &envsize);
990 free_windows_environment(p);
995 /* Allow any GSSAPI methods that we've used to alter
996 * the childs environment as they see fit
998 ssh_gssapi_do_child(&env, &envsize);
1001 if (!options.use_login) {
1002 /* Set basic environment. */
1003 for (i = 0; i < s->num_env; i++)
1004 child_set_env(&env, &envsize, s->env[i].name,
1007 child_set_env(&env, &envsize, "USER", pw->pw_name);
1008 child_set_env(&env, &envsize, "LOGNAME", pw->pw_name);
1010 child_set_env(&env, &envsize, "LOGIN", pw->pw_name);
1012 child_set_env(&env, &envsize, "HOME", pw->pw_dir);
1013 #ifdef HAVE_LOGIN_CAP
1014 if (setusercontext(lc, pw, pw->pw_uid, LOGIN_SETPATH) < 0)
1015 child_set_env(&env, &envsize, "PATH", _PATH_STDPATH);
1017 child_set_env(&env, &envsize, "PATH", getenv("PATH"));
1018 #else /* HAVE_LOGIN_CAP */
1019 # ifndef HAVE_CYGWIN
1021 * There's no standard path on Windows. The path contains
1022 * important components pointing to the system directories,
1023 * needed for loading shared libraries. So the path better
1024 * remains intact here.
1026 # ifdef HAVE_ETC_DEFAULT_LOGIN
1027 read_etc_default_login(&env, &envsize, pw->pw_uid);
1028 path = child_get_env(env, "PATH");
1029 # endif /* HAVE_ETC_DEFAULT_LOGIN */
1030 if (path == NULL || *path == '\0') {
1031 child_set_env(&env, &envsize, "PATH",
1032 s->pw->pw_uid == 0 ?
1033 SUPERUSER_PATH : _PATH_STDPATH);
1035 # endif /* HAVE_CYGWIN */
1036 #endif /* HAVE_LOGIN_CAP */
1038 snprintf(buf, sizeof buf, "%.200s/%.50s",
1039 _PATH_MAILDIR, pw->pw_name);
1040 child_set_env(&env, &envsize, "MAIL", buf);
1042 /* Normal systems set SHELL by default. */
1043 child_set_env(&env, &envsize, "SHELL", shell);
1046 child_set_env(&env, &envsize, "TZ", getenv("TZ"));
1048 /* Set custom environment options from RSA authentication. */
1049 if (!options.use_login) {
1050 while (custom_environment) {
1051 struct envstring *ce = custom_environment;
1054 for (i = 0; str[i] != '=' && str[i]; i++)
1056 if (str[i] == '=') {
1058 child_set_env(&env, &envsize, str, str + i + 1);
1060 custom_environment = ce->next;
1066 /* SSH_CLIENT deprecated */
1067 snprintf(buf, sizeof buf, "%.50s %d %d",
1068 get_remote_ipaddr(), get_remote_port(), get_local_port());
1069 child_set_env(&env, &envsize, "SSH_CLIENT", buf);
1071 laddr = get_local_ipaddr(packet_get_connection_in());
1072 snprintf(buf, sizeof buf, "%.50s %d %.50s %d",
1073 get_remote_ipaddr(), get_remote_port(), laddr, get_local_port());
1075 child_set_env(&env, &envsize, "SSH_CONNECTION", buf);
1078 child_set_env(&env, &envsize, "SSH_TTY", s->tty);
1080 child_set_env(&env, &envsize, "TERM", s->term);
1082 child_set_env(&env, &envsize, "DISPLAY", s->display);
1083 if (original_command)
1084 child_set_env(&env, &envsize, "SSH_ORIGINAL_COMMAND",
1088 if (cray_tmpdir[0] != '\0')
1089 child_set_env(&env, &envsize, "TMPDIR", cray_tmpdir);
1090 #endif /* _UNICOS */
1093 * Since we clear KRB5CCNAME at startup, if it's set now then it
1094 * must have been set by a native authentication method (eg AIX or
1095 * SIA), so copy it to the child.
1100 if ((cp = getenv("KRB5CCNAME")) != NULL)
1101 child_set_env(&env, &envsize, "KRB5CCNAME", cp);
1108 if ((cp = getenv("AUTHSTATE")) != NULL)
1109 child_set_env(&env, &envsize, "AUTHSTATE", cp);
1110 read_environment_file(&env, &envsize, "/etc/environment");
1114 if (s->authctxt->krb5_ccname)
1115 child_set_env(&env, &envsize, "KRB5CCNAME",
1116 s->authctxt->krb5_ccname);
1120 * Pull in any environment variables that may have
1123 if (options.use_pam) {
1126 p = fetch_pam_child_environment();
1127 copy_environment(p, &env, &envsize);
1128 free_pam_environment(p);
1130 p = fetch_pam_environment();
1131 copy_environment(p, &env, &envsize);
1132 free_pam_environment(p);
1134 #endif /* USE_PAM */
1136 if (auth_sock_name != NULL)
1137 child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME,
1140 /* read $HOME/.ssh/environment. */
1141 if (options.permit_user_env && !options.use_login) {
1142 snprintf(buf, sizeof buf, "%.200s/.ssh/environment",
1143 strcmp(pw->pw_dir, "/") ? pw->pw_dir : "");
1144 read_environment_file(&env, &envsize, buf);
1147 /* dump the environment */
1148 fprintf(stderr, "Environment:\n");
1149 for (i = 0; env[i]; i++)
1150 fprintf(stderr, " %.200s\n", env[i]);
1156 * Run $HOME/.ssh/rc, /etc/ssh/sshrc, or xauth (whichever is found
1157 * first in this order).
1160 do_rc_files(Session *s, const char *shell)
1168 s->display != NULL && s->auth_proto != NULL && s->auth_data != NULL;
1170 /* ignore _PATH_SSH_USER_RC for subsystems */
1171 if (!s->is_subsystem && (stat(_PATH_SSH_USER_RC, &st) >= 0)) {
1172 snprintf(cmd, sizeof cmd, "%s -c '%s %s'",
1173 shell, _PATH_BSHELL, _PATH_SSH_USER_RC);
1175 fprintf(stderr, "Running %s\n", cmd);
1176 f = popen(cmd, "w");
1179 fprintf(f, "%s %s\n", s->auth_proto,
1183 fprintf(stderr, "Could not run %s\n",
1185 } else if (stat(_PATH_SSH_SYSTEM_RC, &st) >= 0) {
1187 fprintf(stderr, "Running %s %s\n", _PATH_BSHELL,
1188 _PATH_SSH_SYSTEM_RC);
1189 f = popen(_PATH_BSHELL " " _PATH_SSH_SYSTEM_RC, "w");
1192 fprintf(f, "%s %s\n", s->auth_proto,
1196 fprintf(stderr, "Could not run %s\n",
1197 _PATH_SSH_SYSTEM_RC);
1198 } else if (do_xauth && options.xauth_location != NULL) {
1199 /* Add authority data to .Xauthority if appropriate. */
1202 "Running %.500s remove %.100s\n",
1203 options.xauth_location, s->auth_display);
1205 "%.500s add %.100s %.100s %.100s\n",
1206 options.xauth_location, s->auth_display,
1207 s->auth_proto, s->auth_data);
1209 snprintf(cmd, sizeof cmd, "%s -q -",
1210 options.xauth_location);
1211 f = popen(cmd, "w");
1213 fprintf(f, "remove %s\n",
1215 fprintf(f, "add %s %s %s\n",
1216 s->auth_display, s->auth_proto,
1220 fprintf(stderr, "Could not run %s\n",
1227 do_nologin(struct passwd *pw)
1232 #ifdef HAVE_LOGIN_CAP
1233 if (!login_getcapbool(lc, "ignorenologin", 0) && pw->pw_uid)
1234 f = fopen(login_getcapstr(lc, "nologin", _PATH_NOLOGIN,
1235 _PATH_NOLOGIN), "r");
1238 f = fopen(_PATH_NOLOGIN, "r");
1241 /* /etc/nologin exists. Print its contents and exit. */
1242 logit("User %.100s not allowed because %s exists",
1243 pw->pw_name, _PATH_NOLOGIN);
1244 while (fgets(buf, sizeof(buf), f))
1252 /* Set login name, uid, gid, and groups. */
1254 do_setusercontext(struct passwd *pw)
1257 if (getuid() == 0 || geteuid() == 0)
1258 #endif /* HAVE_CYGWIN */
1261 #ifdef HAVE_SETPCRED
1262 if (setpcred(pw->pw_name, (char **)NULL) == -1)
1263 fatal("Failed to set process credentials");
1264 #endif /* HAVE_SETPCRED */
1265 #ifdef HAVE_LOGIN_CAP
1270 if (options.gss_authentication) {
1271 temporarily_use_uid(pw);
1272 ssh_gssapi_storecreds();
1277 if (options.use_pam) {
1281 # endif /* USE_PAM */
1282 if (setusercontext(lc, pw, pw->pw_uid,
1283 (LOGIN_SETALL & ~LOGIN_SETPATH)) < 0) {
1284 perror("unable to set user context");
1288 # if defined(HAVE_GETLUID) && defined(HAVE_SETLUID)
1289 /* Sets login uid for accounting */
1290 if (getluid() == -1 && setluid(pw->pw_uid) == -1)
1291 error("setluid: %s", strerror(errno));
1292 # endif /* defined(HAVE_GETLUID) && defined(HAVE_SETLUID) */
1294 if (setlogin(pw->pw_name) < 0)
1295 error("setlogin failed: %s", strerror(errno));
1296 if (setgid(pw->pw_gid) < 0) {
1300 /* Initialize the group list. */
1301 if (initgroups(pw->pw_name, pw->pw_gid) < 0) {
1302 perror("initgroups");
1307 if (options.gss_authentication) {
1308 temporarily_use_uid(pw);
1309 ssh_gssapi_storecreds();
1315 * PAM credentials may take the form of supplementary groups.
1316 * These will have been wiped by the above initgroups() call.
1317 * Reestablish them here.
1319 if (options.use_pam) {
1323 # endif /* USE_PAM */
1324 # if defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY)
1325 irix_setusercontext(pw);
1326 # endif /* defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) */
1330 #if defined(HAVE_LIBIAF) && !defined(BROKEN_LIBIAF)
1331 if (set_id(pw->pw_name) != 0) {
1334 #endif /* HAVE_LIBIAF && !BROKEN_LIBIAF */
1335 /* Permanently switch to the desired uid. */
1336 permanently_set_uid(pw);
1343 if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid)
1344 fatal("Failed to set uids to %u.", (u_int) pw->pw_uid);
1348 do_pwchange(Session *s)
1351 fprintf(stderr, "WARNING: Your password has expired.\n");
1352 if (s->ttyfd != -1) {
1354 "You must change your password now and login again!\n");
1355 #ifdef PASSWD_NEEDS_USERNAME
1356 execl(_PATH_PASSWD_PROG, "passwd", s->pw->pw_name,
1359 execl(_PATH_PASSWD_PROG, "passwd", (char *)NULL);
1364 "Password change required but no TTY available.\n");
1370 launch_login(struct passwd *pw, const char *hostname)
1372 /* Launch login(1). */
1374 execl(LOGIN_PROGRAM, "login", "-h", hostname,
1375 #ifdef xxxLOGIN_NEEDS_TERM
1376 (s->term ? s->term : "unknown"),
1377 #endif /* LOGIN_NEEDS_TERM */
1378 #ifdef LOGIN_NO_ENDOPT
1379 "-p", "-f", pw->pw_name, (char *)NULL);
1381 "-p", "-f", "--", pw->pw_name, (char *)NULL);
1384 /* Login couldn't be executed, die. */
1391 child_close_fds(void)
1395 if (packet_get_connection_in() == packet_get_connection_out())
1396 close(packet_get_connection_in());
1398 close(packet_get_connection_in());
1399 close(packet_get_connection_out());
1402 * Close all descriptors related to channels. They will still remain
1403 * open in the parent.
1405 /* XXX better use close-on-exec? -markus */
1406 channel_close_all();
1409 * Close any extra file descriptors. Note that there may still be
1410 * descriptors left by system functions. They will be closed later.
1415 * Close any extra open file descriptors so that we don't have them
1416 * hanging around in clients. Note that we want to do this after
1417 * initgroups, because at least on Solaris 2.3 it leaves file
1420 for (i = 3; i < 64; i++)
1425 * Performs common processing for the child, such as setting up the
1426 * environment, closing extra file descriptors, setting the user and group
1427 * ids, and executing the command or shell.
1430 do_child(Session *s, const char *command)
1432 extern char **environ;
1435 const char *shell, *shell0, *hostname = NULL;
1436 struct passwd *pw = s->pw;
1438 /* remove hostkey from the child's memory */
1439 destroy_sensitive_data();
1441 /* Force a password change */
1442 if (s->authctxt->force_pwchange) {
1443 do_setusercontext(pw);
1449 /* login(1) is only called if we execute the login shell */
1450 if (options.use_login && command != NULL)
1451 options.use_login = 0;
1454 cray_setup(pw->pw_uid, pw->pw_name, command);
1455 #endif /* _UNICOS */
1458 * Login(1) does this as well, and it needs uid 0 for the "-h"
1459 * switch, so we let login(1) to this for us.
1461 if (!options.use_login) {
1463 session_setup_sia(pw, s->ttyfd == -1 ? NULL : s->tty);
1464 if (!check_quietlogin(s, command))
1466 #else /* HAVE_OSF_SIA */
1467 /* When PAM is enabled we rely on it to do the nologin check */
1468 if (!options.use_pam)
1470 do_setusercontext(pw);
1472 * PAM session modules in do_setusercontext may have
1473 * generated messages, so if this in an interactive
1474 * login then display them too.
1476 if (!check_quietlogin(s, command))
1478 #endif /* HAVE_OSF_SIA */
1482 if (options.use_pam && !options.use_login && !is_pam_session_open()) {
1483 debug3("PAM session not opened, exiting");
1490 * Get the shell from the password data. An empty shell field is
1491 * legal, and means /bin/sh.
1493 shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
1496 * Make sure $SHELL points to the shell from the password file,
1497 * even if shell is overridden from login.conf
1499 env = do_setup_env(s, shell);
1501 #ifdef HAVE_LOGIN_CAP
1502 shell = login_getcapstr(lc, "shell", (char *)shell, (char *)shell);
1505 /* we have to stash the hostname before we close our socket. */
1506 if (options.use_login)
1507 hostname = get_remote_name_or_ip(utmp_len,
1510 * Close the connection descriptors; note that this is the child, and
1511 * the server will still have the socket open, and it is important
1512 * that we do not shutdown it. Note that the descriptors cannot be
1513 * closed before building the environment, as we call
1514 * get_remote_ipaddr there.
1519 * Must take new environment into use so that .ssh/rc,
1520 * /etc/ssh/sshrc and xauth are run in the proper environment.
1524 #if defined(KRB5) && defined(USE_AFS)
1526 * At this point, we check to see if AFS is active and if we have
1527 * a valid Kerberos 5 TGT. If so, it seems like a good idea to see
1528 * if we can (and need to) extend the ticket into an AFS token. If
1529 * we don't do this, we run into potential problems if the user's
1530 * home directory is in AFS and it's not world-readable.
1533 if (options.kerberos_get_afs_token && k_hasafs() &&
1534 (s->authctxt->krb5_ctx != NULL)) {
1537 debug("Getting AFS token");
1541 if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0)
1542 krb5_afslog(s->authctxt->krb5_ctx,
1543 s->authctxt->krb5_fwd_ccache, cell, NULL);
1545 krb5_afslog_home(s->authctxt->krb5_ctx,
1546 s->authctxt->krb5_fwd_ccache, NULL, NULL, pw->pw_dir);
1550 /* Change current directory to the user's home directory. */
1551 if (chdir(pw->pw_dir) < 0) {
1552 fprintf(stderr, "Could not chdir to home directory %s: %s\n",
1553 pw->pw_dir, strerror(errno));
1554 #ifdef HAVE_LOGIN_CAP
1555 if (login_getcapbool(lc, "requirehome", 0))
1560 if (!options.use_login)
1561 do_rc_files(s, shell);
1563 /* restore SIGPIPE for child */
1564 signal(SIGPIPE, SIG_DFL);
1566 if (options.use_login) {
1567 launch_login(pw, hostname);
1571 /* Get the last component of the shell name. */
1572 if ((shell0 = strrchr(shell, '/')) != NULL)
1578 * If we have no command, execute the shell. In this case, the shell
1579 * name to be passed in argv[0] is preceded by '-' to indicate that
1580 * this is a login shell.
1585 /* Start the shell. Set initial character to '-'. */
1588 if (strlcpy(argv0 + 1, shell0, sizeof(argv0) - 1)
1589 >= sizeof(argv0) - 1) {
1595 /* Execute the shell. */
1598 execve(shell, argv, env);
1600 /* Executing the shell failed. */
1605 * Execute the command using the user's shell. This uses the -c
1606 * option to execute the command.
1608 argv[0] = (char *) shell0;
1610 argv[2] = (char *) command;
1612 execve(shell, argv, env);
1621 static int did_init = 0;
1623 debug("session_new: init");
1624 for (i = 0; i < MAX_SESSIONS; i++) {
1625 sessions[i].used = 0;
1629 for (i = 0; i < MAX_SESSIONS; i++) {
1630 Session *s = &sessions[i];
1632 memset(s, 0, sizeof(*s));
1638 s->x11_chanids = NULL;
1639 debug("session_new: session %d", i);
1650 for (i = 0; i < MAX_SESSIONS; i++) {
1651 Session *s = &sessions[i];
1652 debug("dump: used %d session %d %p channel %d pid %ld",
1662 session_open(Authctxt *authctxt, int chanid)
1664 Session *s = session_new();
1665 debug("session_open: channel %d", chanid);
1667 error("no more sessions");
1670 s->authctxt = authctxt;
1671 s->pw = authctxt->pw;
1672 if (s->pw == NULL || !authctxt->valid)
1673 fatal("no user for session %d", s->self);
1674 debug("session_open: session %d: link with channel %d", s->self, chanid);
1680 session_by_tty(char *tty)
1683 for (i = 0; i < MAX_SESSIONS; i++) {
1684 Session *s = &sessions[i];
1685 if (s->used && s->ttyfd != -1 && strcmp(s->tty, tty) == 0) {
1686 debug("session_by_tty: session %d tty %s", i, tty);
1690 debug("session_by_tty: unknown tty %.100s", tty);
1696 session_by_channel(int id)
1699 for (i = 0; i < MAX_SESSIONS; i++) {
1700 Session *s = &sessions[i];
1701 if (s->used && s->chanid == id) {
1702 debug("session_by_channel: session %d channel %d", i, id);
1706 debug("session_by_channel: unknown channel %d", id);
1712 session_by_x11_channel(int id)
1716 for (i = 0; i < MAX_SESSIONS; i++) {
1717 Session *s = &sessions[i];
1719 if (s->x11_chanids == NULL || !s->used)
1721 for (j = 0; s->x11_chanids[j] != -1; j++) {
1722 if (s->x11_chanids[j] == id) {
1723 debug("session_by_x11_channel: session %d "
1724 "channel %d", s->self, id);
1729 debug("session_by_x11_channel: unknown channel %d", id);
1735 session_by_pid(pid_t pid)
1738 debug("session_by_pid: pid %ld", (long)pid);
1739 for (i = 0; i < MAX_SESSIONS; i++) {
1740 Session *s = &sessions[i];
1741 if (s->used && s->pid == pid)
1744 error("session_by_pid: unknown pid %ld", (long)pid);
1750 session_window_change_req(Session *s)
1752 s->col = packet_get_int();
1753 s->row = packet_get_int();
1754 s->xpixel = packet_get_int();
1755 s->ypixel = packet_get_int();
1757 pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1762 session_pty_req(Session *s)
1768 debug("Allocating a pty not permitted for this authentication.");
1771 if (s->ttyfd != -1) {
1772 packet_disconnect("Protocol error: you already have a pty.");
1776 s->term = packet_get_string(&len);
1779 s->col = packet_get_int();
1780 s->row = packet_get_int();
1782 s->row = packet_get_int();
1783 s->col = packet_get_int();
1785 s->xpixel = packet_get_int();
1786 s->ypixel = packet_get_int();
1788 if (strcmp(s->term, "") == 0) {
1793 /* Allocate a pty and open it. */
1794 debug("Allocating pty.");
1795 if (!PRIVSEP(pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty)))) {
1801 error("session_pty_req: session %d alloc failed", s->self);
1804 debug("session_pty_req: session %d alloc %s", s->self, s->tty);
1806 /* for SSH1 the tty modes length is not given */
1808 n_bytes = packet_remaining();
1809 tty_parse_modes(s->ttyfd, &n_bytes);
1812 pty_setowner(s->pw, s->tty);
1814 /* Set window size from the packet. */
1815 pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1818 session_proctitle(s);
1823 session_subsystem_req(Session *s)
1828 char *cmd, *subsys = packet_get_string(&len);
1832 logit("subsystem request for %.100s", subsys);
1834 for (i = 0; i < options.num_subsystems; i++) {
1835 if (strcmp(subsys, options.subsystem_name[i]) == 0) {
1836 cmd = options.subsystem_command[i];
1837 if (stat(cmd, &st) < 0) {
1838 error("subsystem: cannot stat %s: %s", cmd,
1842 debug("subsystem: exec() %s", cmd);
1843 s->is_subsystem = 1;
1851 logit("subsystem request for %.100s failed, subsystem not found",
1859 session_x11_req(Session *s)
1863 if (s->auth_proto != NULL || s->auth_data != NULL) {
1864 error("session_x11_req: session %d: "
1865 "x11 forwarding already active", s->self);
1868 s->single_connection = packet_get_char();
1869 s->auth_proto = packet_get_string(NULL);
1870 s->auth_data = packet_get_string(NULL);
1871 s->screen = packet_get_int();
1874 success = session_setup_x11fwd(s);
1876 xfree(s->auth_proto);
1877 xfree(s->auth_data);
1878 s->auth_proto = NULL;
1879 s->auth_data = NULL;
1885 session_shell_req(Session *s)
1893 session_exec_req(Session *s)
1896 char *command = packet_get_string(&len);
1898 do_exec(s, command);
1904 session_break_req(Session *s)
1907 packet_get_int(); /* ignored */
1910 if (s->ttyfd == -1 ||
1911 tcsendbreak(s->ttyfd, 0) < 0)
1917 session_env_req(Session *s)
1920 u_int name_len, val_len, i;
1922 name = packet_get_string(&name_len);
1923 val = packet_get_string(&val_len);
1926 /* Don't set too many environment variables */
1927 if (s->num_env > 128) {
1928 debug2("Ignoring env request %s: too many env vars", name);
1932 for (i = 0; i < options.num_accept_env; i++) {
1933 if (match_pattern(name, options.accept_env[i])) {
1934 debug2("Setting env %d: %s=%s", s->num_env, name, val);
1935 s->env = xrealloc(s->env, sizeof(*s->env) *
1937 s->env[s->num_env].name = name;
1938 s->env[s->num_env].val = val;
1943 debug2("Ignoring env request %s: disallowed name", name);
1952 session_auth_agent_req(Session *s)
1954 static int called = 0;
1956 if (no_agent_forwarding_flag) {
1957 debug("session_auth_agent_req: no_agent_forwarding_flag");
1964 return auth_input_request_forwarding(s->pw);
1969 session_input_channel_req(Channel *c, const char *rtype)
1974 if ((s = session_by_channel(c->self)) == NULL) {
1975 logit("session_input_channel_req: no session %d req %.100s",
1979 debug("session_input_channel_req: session %d req %s", s->self, rtype);
1982 * a session is in LARVAL state until a shell, a command
1983 * or a subsystem is executed
1985 if (c->type == SSH_CHANNEL_LARVAL) {
1986 if (strcmp(rtype, "shell") == 0) {
1987 success = session_shell_req(s);
1988 } else if (strcmp(rtype, "exec") == 0) {
1989 success = session_exec_req(s);
1990 } else if (strcmp(rtype, "pty-req") == 0) {
1991 success = session_pty_req(s);
1992 } else if (strcmp(rtype, "x11-req") == 0) {
1993 success = session_x11_req(s);
1994 } else if (strcmp(rtype, "auth-agent-req@openssh.com") == 0) {
1995 success = session_auth_agent_req(s);
1996 } else if (strcmp(rtype, "subsystem") == 0) {
1997 success = session_subsystem_req(s);
1998 } else if (strcmp(rtype, "env") == 0) {
1999 success = session_env_req(s);
2002 if (strcmp(rtype, "window-change") == 0) {
2003 success = session_window_change_req(s);
2004 } else if (strcmp(rtype, "break") == 0) {
2005 success = session_break_req(s);
2012 session_set_fds(Session *s, int fdin, int fdout, int fderr)
2015 fatal("session_set_fds: called for proto != 2.0");
2017 * now that have a child and a pipe to the child,
2018 * we can activate our channel and register the fd's
2020 if (s->chanid == -1)
2021 fatal("no channel for session %d", s->self);
2022 channel_set_fds(s->chanid,
2024 fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ,
2026 CHAN_SES_WINDOW_DEFAULT);
2030 * Function to perform pty cleanup. Also called if we get aborted abnormally
2031 * (e.g., due to a dropped connection).
2034 session_pty_cleanup2(Session *s)
2037 error("session_pty_cleanup: no session");
2043 debug("session_pty_cleanup: session %d release %s", s->self, s->tty);
2045 /* Record that the user has logged out. */
2047 record_logout(s->pid, s->tty, s->pw->pw_name);
2049 /* Release the pseudo-tty. */
2051 pty_release(s->tty);
2054 * Close the server side of the socket pairs. We must do this after
2055 * the pty cleanup, so that another process doesn't get this pty
2056 * while we're still cleaning up.
2058 if (close(s->ptymaster) < 0)
2059 error("close(s->ptymaster/%d): %s", s->ptymaster, strerror(errno));
2061 /* unlink pty from session */
2066 session_pty_cleanup(Session *s)
2068 PRIVSEP(session_pty_cleanup2(s));
2074 #define SSH_SIG(x) if (sig == SIG ## x) return #x
2089 return "SIG@openssh.com";
2093 session_close_x11(int id)
2097 if ((c = channel_by_id(id)) == NULL) {
2098 debug("session_close_x11: x11 channel %d missing", id);
2100 /* Detach X11 listener */
2101 debug("session_close_x11: detach x11 channel %d", id);
2102 channel_cancel_cleanup(id);
2103 if (c->ostate != CHAN_OUTPUT_CLOSED)
2109 session_close_single_x11(int id, void *arg)
2114 debug3("session_close_single_x11: channel %d", id);
2115 channel_cancel_cleanup(id);
2116 if ((s = session_by_x11_channel(id)) == NULL)
2117 fatal("session_close_single_x11: no x11 channel %d", id);
2118 for (i = 0; s->x11_chanids[i] != -1; i++) {
2119 debug("session_close_single_x11: session %d: "
2120 "closing channel %d", s->self, s->x11_chanids[i]);
2122 * The channel "id" is already closing, but make sure we
2123 * close all of its siblings.
2125 if (s->x11_chanids[i] != id)
2126 session_close_x11(s->x11_chanids[i]);
2128 xfree(s->x11_chanids);
2129 s->x11_chanids = NULL;
2134 if (s->auth_proto) {
2135 xfree(s->auth_proto);
2136 s->auth_proto = NULL;
2139 xfree(s->auth_data);
2140 s->auth_data = NULL;
2142 if (s->auth_display) {
2143 xfree(s->auth_display);
2144 s->auth_display = NULL;
2149 session_exit_message(Session *s, int status)
2153 if ((c = channel_lookup(s->chanid)) == NULL)
2154 fatal("session_exit_message: session %d: no channel %d",
2155 s->self, s->chanid);
2156 debug("session_exit_message: session %d channel %d pid %ld",
2157 s->self, s->chanid, (long)s->pid);
2159 if (WIFEXITED(status)) {
2160 channel_request_start(s->chanid, "exit-status", 0);
2161 packet_put_int(WEXITSTATUS(status));
2163 } else if (WIFSIGNALED(status)) {
2164 channel_request_start(s->chanid, "exit-signal", 0);
2165 packet_put_cstring(sig2name(WTERMSIG(status)));
2167 packet_put_char(WCOREDUMP(status));
2168 #else /* WCOREDUMP */
2170 #endif /* WCOREDUMP */
2171 packet_put_cstring("");
2172 packet_put_cstring("");
2175 /* Some weird exit cause. Just exit. */
2176 packet_disconnect("wait returned status %04x.", status);
2179 /* disconnect channel */
2180 debug("session_exit_message: release channel %d", s->chanid);
2183 * Adjust cleanup callback attachment to send close messages when
2184 * the channel gets EOF. The session will be then be closed
2185 * by session_close_by_channel when the childs close their fds.
2187 channel_register_cleanup(c->self, session_close_by_channel, 1);
2190 * emulate a write failure with 'chan_write_failed', nobody will be
2191 * interested in data we write.
2192 * Note that we must not call 'chan_read_failed', since there could
2193 * be some more data waiting in the pipe.
2195 if (c->ostate != CHAN_OUTPUT_CLOSED)
2196 chan_write_failed(c);
2200 session_close(Session *s)
2204 debug("session_close: session %d pid %ld", s->self, (long)s->pid);
2206 session_pty_cleanup(s);
2212 xfree(s->x11_chanids);
2213 if (s->auth_display)
2214 xfree(s->auth_display);
2216 xfree(s->auth_data);
2218 xfree(s->auth_proto);
2220 for (i = 0; i < s->num_env; i++) {
2221 xfree(s->env[i].name);
2222 xfree(s->env[i].val);
2226 session_proctitle(s);
2230 session_close_by_pid(pid_t pid, int status)
2232 Session *s = session_by_pid(pid);
2234 debug("session_close_by_pid: no session for pid %ld",
2238 if (s->chanid != -1)
2239 session_exit_message(s, status);
2241 session_pty_cleanup(s);
2246 * this is called when a channel dies before
2247 * the session 'child' itself dies
2250 session_close_by_channel(int id, void *arg)
2252 Session *s = session_by_channel(id);
2256 debug("session_close_by_channel: no session for id %d", id);
2259 debug("session_close_by_channel: channel %d child %ld",
2262 debug("session_close_by_channel: channel %d: has child", id);
2264 * delay detach of session, but release pty, since
2265 * the fd's to the child are already closed
2268 session_pty_cleanup(s);
2271 /* detach by removing callback */
2272 channel_cancel_cleanup(s->chanid);
2274 /* Close any X11 listeners associated with this session */
2275 if (s->x11_chanids != NULL) {
2276 for (i = 0; s->x11_chanids[i] != -1; i++) {
2277 session_close_x11(s->x11_chanids[i]);
2278 s->x11_chanids[i] = -1;
2287 session_destroy_all(void (*closefunc)(Session *))
2290 for (i = 0; i < MAX_SESSIONS; i++) {
2291 Session *s = &sessions[i];
2293 if (closefunc != NULL)
2302 session_tty_list(void)
2304 static char buf[1024];
2309 for (i = 0; i < MAX_SESSIONS; i++) {
2310 Session *s = &sessions[i];
2311 if (s->used && s->ttyfd != -1) {
2313 if (strncmp(s->tty, "/dev/", 5) != 0) {
2314 cp = strrchr(s->tty, '/');
2315 cp = (cp == NULL) ? s->tty : cp + 1;
2320 strlcat(buf, ",", sizeof buf);
2321 strlcat(buf, cp, sizeof buf);
2325 strlcpy(buf, "notty", sizeof buf);
2330 session_proctitle(Session *s)
2333 error("no user for session %d", s->self);
2335 setproctitle("%s@%s", s->pw->pw_name, session_tty_list());
2339 session_setup_x11fwd(Session *s)
2342 char display[512], auth_display[512];
2343 char hostname[MAXHOSTNAMELEN];
2346 if (no_x11_forwarding_flag) {
2347 packet_send_debug("X11 forwarding disabled in user configuration file.");
2350 if (!options.x11_forwarding) {
2351 debug("X11 forwarding disabled in server configuration file.");
2354 if (!options.xauth_location ||
2355 (stat(options.xauth_location, &st) == -1)) {
2356 packet_send_debug("No xauth program; cannot forward with spoofing.");
2359 if (options.use_login) {
2360 packet_send_debug("X11 forwarding disabled; "
2361 "not compatible with UseLogin=yes.");
2364 if (s->display != NULL) {
2365 debug("X11 display already set.");
2368 if (x11_create_display_inet(options.x11_display_offset,
2369 options.x11_use_localhost, s->single_connection,
2370 &s->display_number, &s->x11_chanids) == -1) {
2371 debug("x11_create_display_inet failed.");
2374 for (i = 0; s->x11_chanids[i] != -1; i++) {
2375 channel_register_cleanup(s->x11_chanids[i],
2376 session_close_single_x11, 0);
2379 /* Set up a suitable value for the DISPLAY variable. */
2380 if (gethostname(hostname, sizeof(hostname)) < 0)
2381 fatal("gethostname: %.100s", strerror(errno));
2383 * auth_display must be used as the displayname when the
2384 * authorization entry is added with xauth(1). This will be
2385 * different than the DISPLAY string for localhost displays.
2387 if (options.x11_use_localhost) {
2388 snprintf(display, sizeof display, "localhost:%u.%u",
2389 s->display_number, s->screen);
2390 snprintf(auth_display, sizeof auth_display, "unix:%u.%u",
2391 s->display_number, s->screen);
2392 s->display = xstrdup(display);
2393 s->auth_display = xstrdup(auth_display);
2395 #ifdef IPADDR_IN_DISPLAY
2397 struct in_addr my_addr;
2399 he = gethostbyname(hostname);
2401 error("Can't get IP address for X11 DISPLAY.");
2402 packet_send_debug("Can't get IP address for X11 DISPLAY.");
2405 memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr));
2406 snprintf(display, sizeof display, "%.50s:%u.%u", inet_ntoa(my_addr),
2407 s->display_number, s->screen);
2409 snprintf(display, sizeof display, "%.400s:%u.%u", hostname,
2410 s->display_number, s->screen);
2412 s->display = xstrdup(display);
2413 s->auth_display = xstrdup(display);
2420 do_authenticated2(Authctxt *authctxt)
2422 server_loop2(authctxt);
2426 do_cleanup(Authctxt *authctxt)
2428 static int called = 0;
2430 debug("do_cleanup");
2432 /* no cleanup if we're in the child for login shell */
2436 /* avoid double cleanup */
2441 if (authctxt == NULL)
2444 if (options.kerberos_ticket_cleanup &&
2446 krb5_cleanup_proc(authctxt);
2450 if (compat20 && options.gss_cleanup_creds)
2451 ssh_gssapi_cleanup_creds();
2455 if (options.use_pam) {
2457 sshpam_thread_cleanup();
2461 /* remove agent socket */
2462 auth_sock_cleanup_proc(authctxt->pw);
2465 * Cleanup ptys/utmp only if privsep is disabled,
2466 * or if running in monitor.
2468 if (!use_privsep || mm_is_monitor())
2469 session_destroy_all(session_pty_cleanup2);