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 1.191 2005/12/24 02:27:41 djm 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);
212 /* setup the channel layer */
213 if (!no_port_forwarding_flag && options.allow_tcp_forwarding)
214 channel_permit_all_opens();
217 do_authenticated2(authctxt);
219 do_authenticated1(authctxt);
221 do_cleanup(authctxt);
225 * Prepares for an interactive session. This is called after the user has
226 * been successfully authenticated. During this message exchange, pseudo
227 * terminals are allocated, X11, TCP/IP, and authentication agent forwardings
228 * are requested, etc.
231 do_authenticated1(Authctxt *authctxt)
235 int success, type, screen_flag;
236 int enable_compression_after_reply = 0;
237 u_int proto_len, data_len, dlen, compression_level = 0;
241 error("no more sessions");
244 s->authctxt = authctxt;
245 s->pw = authctxt->pw;
248 * We stay in this loop until the client requests to execute a shell
254 /* Get a packet from the client. */
255 type = packet_read();
257 /* Process the packet. */
259 case SSH_CMSG_REQUEST_COMPRESSION:
260 compression_level = packet_get_int();
262 if (compression_level < 1 || compression_level > 9) {
263 packet_send_debug("Received invalid compression level %d.",
267 if (options.compression == COMP_NONE) {
268 debug2("compression disabled");
271 /* Enable compression after we have responded with SUCCESS. */
272 enable_compression_after_reply = 1;
276 case SSH_CMSG_REQUEST_PTY:
277 success = session_pty_req(s);
280 case SSH_CMSG_X11_REQUEST_FORWARDING:
281 s->auth_proto = packet_get_string(&proto_len);
282 s->auth_data = packet_get_string(&data_len);
284 screen_flag = packet_get_protocol_flags() &
285 SSH_PROTOFLAG_SCREEN_NUMBER;
286 debug2("SSH_PROTOFLAG_SCREEN_NUMBER: %d", screen_flag);
288 if (packet_remaining() == 4) {
290 debug2("Buggy client: "
291 "X11 screen flag missing");
292 s->screen = packet_get_int();
297 success = session_setup_x11fwd(s);
299 xfree(s->auth_proto);
301 s->auth_proto = NULL;
306 case SSH_CMSG_AGENT_REQUEST_FORWARDING:
307 if (no_agent_forwarding_flag || compat13) {
308 debug("Authentication agent forwarding not permitted for this authentication.");
311 debug("Received authentication agent forwarding request.");
312 success = auth_input_request_forwarding(s->pw);
315 case SSH_CMSG_PORT_FORWARD_REQUEST:
316 if (no_port_forwarding_flag) {
317 debug("Port forwarding not permitted for this authentication.");
320 if (!options.allow_tcp_forwarding) {
321 debug("Port forwarding not permitted.");
324 debug("Received TCP/IP port forwarding request.");
325 channel_input_port_forward_request(s->pw->pw_uid == 0, options.gateway_ports);
329 case SSH_CMSG_MAX_PACKET_SIZE:
330 if (packet_set_maxsize(packet_get_int()) > 0)
334 case SSH_CMSG_EXEC_SHELL:
335 case SSH_CMSG_EXEC_CMD:
336 if (type == SSH_CMSG_EXEC_CMD) {
337 command = packet_get_string(&dlen);
338 debug("Exec command '%.500s'", command);
350 * Any unknown messages in this phase are ignored,
351 * and a failure message is returned.
353 logit("Unknown packet type received after authentication: %d", type);
355 packet_start(success ? SSH_SMSG_SUCCESS : SSH_SMSG_FAILURE);
359 /* Enable compression now that we have replied if appropriate. */
360 if (enable_compression_after_reply) {
361 enable_compression_after_reply = 0;
362 packet_start_compression(compression_level);
368 * This is called to fork and execute a command when we have no tty. This
369 * will call do_child from the child, and server_loop from the parent after
370 * setting up file descriptors and such.
373 do_exec_no_pty(Session *s, const char *command)
378 int pin[2], pout[2], perr[2];
379 /* Allocate pipes for communicating with the program. */
380 if (pipe(pin) < 0 || pipe(pout) < 0 || pipe(perr) < 0)
381 packet_disconnect("Could not create pipes: %.100s",
383 #else /* USE_PIPES */
384 int inout[2], err[2];
385 /* Uses socket pairs to communicate with the program. */
386 if (socketpair(AF_UNIX, SOCK_STREAM, 0, inout) < 0 ||
387 socketpair(AF_UNIX, SOCK_STREAM, 0, err) < 0)
388 packet_disconnect("Could not create socket pairs: %.100s",
390 #endif /* USE_PIPES */
392 fatal("do_exec_no_pty: no session");
394 session_proctitle(s);
397 if (options.use_pam && !use_privsep)
401 /* Fork the child. */
402 if ((pid = fork()) == 0) {
405 /* Child. Reinitialize the log since the pid has changed. */
406 log_init(__progname, options.log_level, options.log_facility, log_stderr);
409 * Create a new session and process group since the 4.4BSD
410 * setlogin() affects the entire process group.
413 error("setsid failed: %.100s", strerror(errno));
417 * Redirect stdin. We close the parent side of the socket
418 * pair, and make the child side the standard input.
421 if (dup2(pin[0], 0) < 0)
422 perror("dup2 stdin");
425 /* Redirect stdout. */
427 if (dup2(pout[1], 1) < 0)
428 perror("dup2 stdout");
431 /* Redirect stderr. */
433 if (dup2(perr[1], 2) < 0)
434 perror("dup2 stderr");
436 #else /* USE_PIPES */
438 * Redirect stdin, stdout, and stderr. Stdin and stdout will
439 * use the same socket, as some programs (particularly rdist)
440 * seem to depend on it.
444 if (dup2(inout[0], 0) < 0) /* stdin */
445 perror("dup2 stdin");
446 if (dup2(inout[0], 1) < 0) /* stdout. Note: same socket as stdin. */
447 perror("dup2 stdout");
448 if (dup2(err[0], 2) < 0) /* stderr */
449 perror("dup2 stderr");
450 #endif /* USE_PIPES */
453 cray_init_job(s->pw); /* set up cray jid and tmpdir */
456 /* Do processing for the child (exec command etc). */
457 do_child(s, command);
461 signal(WJSIGNAL, cray_job_termination_handler);
465 cygwin_set_impersonation_token(INVALID_HANDLE_VALUE);
468 packet_disconnect("fork failed: %.100s", strerror(errno));
470 /* Set interactive/non-interactive mode. */
471 packet_set_interactive(s->display != NULL);
473 /* We are the parent. Close the child sides of the pipes. */
479 if (s->is_subsystem) {
483 session_set_fds(s, pin[1], pout[0], perr[0]);
485 /* Enter the interactive session. */
486 server_loop(pid, pin[1], pout[0], perr[0]);
487 /* server_loop has closed pin[1], pout[0], and perr[0]. */
489 #else /* USE_PIPES */
490 /* We are the parent. Close the child sides of the socket pairs. */
495 * Clear loginmsg, since it's the child's responsibility to display
496 * it to the user, otherwise multiple sessions may accumulate
497 * multiple copies of the login messages.
499 buffer_clear(&loginmsg);
502 * Enter the interactive session. Note: server_loop must be able to
503 * handle the case that fdin and fdout are the same.
506 session_set_fds(s, inout[1], inout[1], s->is_subsystem ? -1 : err[1]);
508 server_loop(pid, inout[1], inout[1], err[1]);
509 /* server_loop has closed inout[1] and err[1]. */
511 #endif /* USE_PIPES */
515 * This is called to fork and execute a command when we have a tty. This
516 * will call do_child from the child, and server_loop from the parent after
517 * setting up file descriptors, controlling tty, updating wtmp, utmp,
518 * lastlog, and other such operations.
521 do_exec_pty(Session *s, const char *command)
523 int fdout, ptyfd, ttyfd, ptymaster;
527 fatal("do_exec_pty: no session");
532 if (options.use_pam) {
533 do_pam_set_tty(s->tty);
539 /* Fork the child. */
540 if ((pid = fork()) == 0) {
543 /* Child. Reinitialize the log because the pid has changed. */
544 log_init(__progname, options.log_level, options.log_facility, log_stderr);
545 /* Close the master side of the pseudo tty. */
548 /* Make the pseudo tty our controlling tty. */
549 pty_make_controlling_tty(&ttyfd, s->tty);
551 /* Redirect stdin/stdout/stderr from the pseudo tty. */
552 if (dup2(ttyfd, 0) < 0)
553 error("dup2 stdin: %s", strerror(errno));
554 if (dup2(ttyfd, 1) < 0)
555 error("dup2 stdout: %s", strerror(errno));
556 if (dup2(ttyfd, 2) < 0)
557 error("dup2 stderr: %s", strerror(errno));
559 /* Close the extra descriptor for the pseudo tty. */
562 /* record login, etc. similar to login(1) */
564 if (!(options.use_login && command == NULL)) {
566 cray_init_job(s->pw); /* set up cray jid and tmpdir */
568 do_login(s, command);
570 # ifdef LOGIN_NEEDS_UTMPX
576 /* Do common processing for the child, such as execing the command. */
577 do_child(s, command);
581 signal(WJSIGNAL, cray_job_termination_handler);
585 cygwin_set_impersonation_token(INVALID_HANDLE_VALUE);
588 packet_disconnect("fork failed: %.100s", strerror(errno));
591 /* Parent. Close the slave side of the pseudo tty. */
595 * Create another descriptor of the pty master side for use as the
596 * standard input. We could use the original descriptor, but this
597 * simplifies code in server_loop. The descriptor is bidirectional.
601 packet_disconnect("dup #1 failed: %.100s", strerror(errno));
603 /* we keep a reference to the pty master */
604 ptymaster = dup(ptyfd);
606 packet_disconnect("dup #2 failed: %.100s", strerror(errno));
607 s->ptymaster = ptymaster;
609 /* Enter interactive session. */
610 packet_set_interactive(1);
612 session_set_fds(s, ptyfd, fdout, -1);
614 server_loop(pid, ptyfd, fdout, -1);
615 /* server_loop _has_ closed ptyfd and fdout. */
619 #ifdef LOGIN_NEEDS_UTMPX
621 do_pre_login(Session *s)
624 struct sockaddr_storage from;
625 pid_t pid = getpid();
628 * Get IP address of client. If the connection is not a socket, let
629 * the address be 0.0.0.0.
631 memset(&from, 0, sizeof(from));
632 fromlen = sizeof(from);
633 if (packet_connection_is_on_socket()) {
634 if (getpeername(packet_get_connection_in(),
635 (struct sockaddr *) & from, &fromlen) < 0) {
636 debug("getpeername: %.100s", strerror(errno));
641 record_utmp_only(pid, s->tty, s->pw->pw_name,
642 get_remote_name_or_ip(utmp_len, options.use_dns),
643 (struct sockaddr *)&from, fromlen);
648 * This is called to fork and execute a command. If another command is
649 * to be forced, execute that instead.
652 do_exec(Session *s, const char *command)
654 if (forced_command) {
655 original_command = command;
656 command = forced_command;
657 debug("Forced command '%.900s'", command);
660 #ifdef SSH_AUDIT_EVENTS
662 PRIVSEP(audit_run_command(command));
663 else if (s->ttyfd == -1) {
664 char *shell = s->pw->pw_shell;
666 if (shell[0] == '\0') /* empty shell means /bin/sh */
668 PRIVSEP(audit_run_command(shell));
673 do_exec_pty(s, command);
675 do_exec_no_pty(s, command);
677 original_command = NULL;
680 * Clear loginmsg: it's the child's responsibility to display
681 * it to the user, otherwise multiple sessions may accumulate
682 * multiple copies of the login messages.
684 buffer_clear(&loginmsg);
687 /* administrative, login(1)-like work */
689 do_login(Session *s, const char *command)
692 struct sockaddr_storage from;
693 struct passwd * pw = s->pw;
694 pid_t pid = getpid();
697 * Get IP address of client. If the connection is not a socket, let
698 * the address be 0.0.0.0.
700 memset(&from, 0, sizeof(from));
701 fromlen = sizeof(from);
702 if (packet_connection_is_on_socket()) {
703 if (getpeername(packet_get_connection_in(),
704 (struct sockaddr *) & from, &fromlen) < 0) {
705 debug("getpeername: %.100s", strerror(errno));
710 /* Record that there was a login on that tty from the remote host. */
712 record_login(pid, s->tty, pw->pw_name, pw->pw_uid,
713 get_remote_name_or_ip(utmp_len,
715 (struct sockaddr *)&from, fromlen);
719 * If password change is needed, do it now.
720 * This needs to occur before the ~/.hushlogin check.
722 if (options.use_pam && !use_privsep && s->authctxt->force_pwchange) {
725 s->authctxt->force_pwchange = 0;
726 /* XXX - signal [net] parent to enable forwardings */
730 if (check_quietlogin(s, command))
739 * Display the message of the day.
747 if (options.print_motd) {
748 #ifdef HAVE_LOGIN_CAP
749 f = fopen(login_getcapstr(lc, "welcome", "/etc/motd",
752 f = fopen("/etc/motd", "r");
755 while (fgets(buf, sizeof(buf), f))
764 * Check for quiet login, either .hushlogin or command given.
767 check_quietlogin(Session *s, const char *command)
770 struct passwd *pw = s->pw;
773 /* Return 1 if .hushlogin exists or a command given. */
776 snprintf(buf, sizeof(buf), "%.200s/.hushlogin", pw->pw_dir);
777 #ifdef HAVE_LOGIN_CAP
778 if (login_getcapbool(lc, "hushlogin", 0) || stat(buf, &st) >= 0)
781 if (stat(buf, &st) >= 0)
788 * Sets the value of the given variable in the environment. If the variable
789 * already exists, its value is overriden.
792 child_set_env(char ***envp, u_int *envsizep, const char *name,
800 * If we're passed an uninitialized list, allocate a single null
801 * entry before continuing.
803 if (*envp == NULL && *envsizep == 0) {
804 *envp = xmalloc(sizeof(char *));
810 * Find the slot where the value should be stored. If the variable
811 * already exists, we reuse the slot; otherwise we append a new slot
812 * at the end of the array, expanding if necessary.
815 namelen = strlen(name);
816 for (i = 0; env[i]; i++)
817 if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=')
820 /* Reuse the slot. */
823 /* New variable. Expand if necessary. */
825 if (i >= envsize - 1) {
827 fatal("child_set_env: too many env vars");
829 env = (*envp) = xrealloc(env, envsize * sizeof(char *));
832 /* Need to set the NULL pointer at end of array beyond the new slot. */
836 /* Allocate space and format the variable in the appropriate slot. */
837 env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1);
838 snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value);
842 * Reads environment variables from the given file and adds/overrides them
843 * into the environment. If the file does not exist, this does nothing.
844 * Otherwise, it must consist of empty lines, comments (line starts with '#')
845 * and assignments of the form name=value. No other forms are allowed.
848 read_environment_file(char ***env, u_int *envsize,
849 const char *filename)
856 f = fopen(filename, "r");
860 while (fgets(buf, sizeof(buf), f)) {
862 fatal("Too many lines in environment file %s", filename);
863 for (cp = buf; *cp == ' ' || *cp == '\t'; cp++)
865 if (!*cp || *cp == '#' || *cp == '\n')
867 if (strchr(cp, '\n'))
868 *strchr(cp, '\n') = '\0';
869 value = strchr(cp, '=');
871 fprintf(stderr, "Bad line %u in %.100s\n", lineno,
876 * Replace the equals sign by nul, and advance value to
881 child_set_env(env, envsize, cp, value);
886 #ifdef HAVE_ETC_DEFAULT_LOGIN
888 * Return named variable from specified environment, or NULL if not present.
891 child_get_env(char **env, const char *name)
897 for (i=0; env[i] != NULL; i++)
898 if (strncmp(name, env[i], len) == 0 && env[i][len] == '=')
899 return(env[i] + len + 1);
904 * Read /etc/default/login.
905 * We pick up the PATH (or SUPATH for root) and UMASK.
908 read_etc_default_login(char ***env, u_int *envsize, uid_t uid)
910 char **tmpenv = NULL, *var;
911 u_int i, tmpenvsize = 0;
915 * We don't want to copy the whole file to the child's environment,
916 * so we use a temporary environment and copy the variables we're
919 read_environment_file(&tmpenv, &tmpenvsize, "/etc/default/login");
925 var = child_get_env(tmpenv, "SUPATH");
927 var = child_get_env(tmpenv, "PATH");
929 child_set_env(env, envsize, "PATH", var);
931 if ((var = child_get_env(tmpenv, "UMASK")) != NULL)
932 if (sscanf(var, "%5lo", &mask) == 1)
935 for (i = 0; tmpenv[i] != NULL; i++)
939 #endif /* HAVE_ETC_DEFAULT_LOGIN */
942 copy_environment(char **source, char ***env, u_int *envsize)
944 char *var_name, *var_val;
950 for(i = 0; source[i] != NULL; i++) {
951 var_name = xstrdup(source[i]);
952 if ((var_val = strstr(var_name, "=")) == NULL) {
958 debug3("Copy environment: %s=%s", var_name, var_val);
959 child_set_env(env, envsize, var_name, var_val);
966 do_setup_env(Session *s, const char *shell)
970 char **env, *laddr, *path = NULL;
971 struct passwd *pw = s->pw;
973 /* Initialize the environment. */
975 env = xmalloc(envsize * sizeof(char *));
980 * The Windows environment contains some setting which are
981 * important for a running system. They must not be dropped.
986 p = fetch_windows_environment();
987 copy_environment(p, &env, &envsize);
988 free_windows_environment(p);
993 /* Allow any GSSAPI methods that we've used to alter
994 * the childs environment as they see fit
996 ssh_gssapi_do_child(&env, &envsize);
999 if (!options.use_login) {
1000 /* Set basic environment. */
1001 for (i = 0; i < s->num_env; i++)
1002 child_set_env(&env, &envsize, s->env[i].name,
1005 child_set_env(&env, &envsize, "USER", pw->pw_name);
1006 child_set_env(&env, &envsize, "LOGNAME", pw->pw_name);
1008 child_set_env(&env, &envsize, "LOGIN", pw->pw_name);
1010 child_set_env(&env, &envsize, "HOME", pw->pw_dir);
1011 #ifdef HAVE_LOGIN_CAP
1012 if (setusercontext(lc, pw, pw->pw_uid, LOGIN_SETPATH) < 0)
1013 child_set_env(&env, &envsize, "PATH", _PATH_STDPATH);
1015 child_set_env(&env, &envsize, "PATH", getenv("PATH"));
1016 #else /* HAVE_LOGIN_CAP */
1017 # ifndef HAVE_CYGWIN
1019 * There's no standard path on Windows. The path contains
1020 * important components pointing to the system directories,
1021 * needed for loading shared libraries. So the path better
1022 * remains intact here.
1024 # ifdef HAVE_ETC_DEFAULT_LOGIN
1025 read_etc_default_login(&env, &envsize, pw->pw_uid);
1026 path = child_get_env(env, "PATH");
1027 # endif /* HAVE_ETC_DEFAULT_LOGIN */
1028 if (path == NULL || *path == '\0') {
1029 child_set_env(&env, &envsize, "PATH",
1030 s->pw->pw_uid == 0 ?
1031 SUPERUSER_PATH : _PATH_STDPATH);
1033 # endif /* HAVE_CYGWIN */
1034 #endif /* HAVE_LOGIN_CAP */
1036 snprintf(buf, sizeof buf, "%.200s/%.50s",
1037 _PATH_MAILDIR, pw->pw_name);
1038 child_set_env(&env, &envsize, "MAIL", buf);
1040 /* Normal systems set SHELL by default. */
1041 child_set_env(&env, &envsize, "SHELL", shell);
1044 child_set_env(&env, &envsize, "TZ", getenv("TZ"));
1046 /* Set custom environment options from RSA authentication. */
1047 if (!options.use_login) {
1048 while (custom_environment) {
1049 struct envstring *ce = custom_environment;
1052 for (i = 0; str[i] != '=' && str[i]; i++)
1054 if (str[i] == '=') {
1056 child_set_env(&env, &envsize, str, str + i + 1);
1058 custom_environment = ce->next;
1064 /* SSH_CLIENT deprecated */
1065 snprintf(buf, sizeof buf, "%.50s %d %d",
1066 get_remote_ipaddr(), get_remote_port(), get_local_port());
1067 child_set_env(&env, &envsize, "SSH_CLIENT", buf);
1069 laddr = get_local_ipaddr(packet_get_connection_in());
1070 snprintf(buf, sizeof buf, "%.50s %d %.50s %d",
1071 get_remote_ipaddr(), get_remote_port(), laddr, get_local_port());
1073 child_set_env(&env, &envsize, "SSH_CONNECTION", buf);
1076 child_set_env(&env, &envsize, "SSH_TTY", s->tty);
1078 child_set_env(&env, &envsize, "TERM", s->term);
1080 child_set_env(&env, &envsize, "DISPLAY", s->display);
1081 if (original_command)
1082 child_set_env(&env, &envsize, "SSH_ORIGINAL_COMMAND",
1086 if (cray_tmpdir[0] != '\0')
1087 child_set_env(&env, &envsize, "TMPDIR", cray_tmpdir);
1088 #endif /* _UNICOS */
1091 * Since we clear KRB5CCNAME at startup, if it's set now then it
1092 * must have been set by a native authentication method (eg AIX or
1093 * SIA), so copy it to the child.
1098 if ((cp = getenv("KRB5CCNAME")) != NULL)
1099 child_set_env(&env, &envsize, "KRB5CCNAME", cp);
1106 if ((cp = getenv("AUTHSTATE")) != NULL)
1107 child_set_env(&env, &envsize, "AUTHSTATE", cp);
1108 read_environment_file(&env, &envsize, "/etc/environment");
1112 if (s->authctxt->krb5_ccname)
1113 child_set_env(&env, &envsize, "KRB5CCNAME",
1114 s->authctxt->krb5_ccname);
1118 * Pull in any environment variables that may have
1121 if (options.use_pam) {
1124 p = fetch_pam_child_environment();
1125 copy_environment(p, &env, &envsize);
1126 free_pam_environment(p);
1128 p = fetch_pam_environment();
1129 copy_environment(p, &env, &envsize);
1130 free_pam_environment(p);
1132 #endif /* USE_PAM */
1134 if (auth_sock_name != NULL)
1135 child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME,
1138 /* read $HOME/.ssh/environment. */
1139 if (options.permit_user_env && !options.use_login) {
1140 snprintf(buf, sizeof buf, "%.200s/.ssh/environment",
1141 strcmp(pw->pw_dir, "/") ? pw->pw_dir : "");
1142 read_environment_file(&env, &envsize, buf);
1145 /* dump the environment */
1146 fprintf(stderr, "Environment:\n");
1147 for (i = 0; env[i]; i++)
1148 fprintf(stderr, " %.200s\n", env[i]);
1154 * Run $HOME/.ssh/rc, /etc/ssh/sshrc, or xauth (whichever is found
1155 * first in this order).
1158 do_rc_files(Session *s, const char *shell)
1166 s->display != NULL && s->auth_proto != NULL && s->auth_data != NULL;
1168 /* ignore _PATH_SSH_USER_RC for subsystems */
1169 if (!s->is_subsystem && (stat(_PATH_SSH_USER_RC, &st) >= 0)) {
1170 snprintf(cmd, sizeof cmd, "%s -c '%s %s'",
1171 shell, _PATH_BSHELL, _PATH_SSH_USER_RC);
1173 fprintf(stderr, "Running %s\n", cmd);
1174 f = popen(cmd, "w");
1177 fprintf(f, "%s %s\n", s->auth_proto,
1181 fprintf(stderr, "Could not run %s\n",
1183 } else if (stat(_PATH_SSH_SYSTEM_RC, &st) >= 0) {
1185 fprintf(stderr, "Running %s %s\n", _PATH_BSHELL,
1186 _PATH_SSH_SYSTEM_RC);
1187 f = popen(_PATH_BSHELL " " _PATH_SSH_SYSTEM_RC, "w");
1190 fprintf(f, "%s %s\n", s->auth_proto,
1194 fprintf(stderr, "Could not run %s\n",
1195 _PATH_SSH_SYSTEM_RC);
1196 } else if (do_xauth && options.xauth_location != NULL) {
1197 /* Add authority data to .Xauthority if appropriate. */
1200 "Running %.500s remove %.100s\n",
1201 options.xauth_location, s->auth_display);
1203 "%.500s add %.100s %.100s %.100s\n",
1204 options.xauth_location, s->auth_display,
1205 s->auth_proto, s->auth_data);
1207 snprintf(cmd, sizeof cmd, "%s -q -",
1208 options.xauth_location);
1209 f = popen(cmd, "w");
1211 fprintf(f, "remove %s\n",
1213 fprintf(f, "add %s %s %s\n",
1214 s->auth_display, s->auth_proto,
1218 fprintf(stderr, "Could not run %s\n",
1225 do_nologin(struct passwd *pw)
1230 #ifdef HAVE_LOGIN_CAP
1231 if (!login_getcapbool(lc, "ignorenologin", 0) && pw->pw_uid)
1232 f = fopen(login_getcapstr(lc, "nologin", _PATH_NOLOGIN,
1233 _PATH_NOLOGIN), "r");
1236 f = fopen(_PATH_NOLOGIN, "r");
1239 /* /etc/nologin exists. Print its contents and exit. */
1240 logit("User %.100s not allowed because %s exists",
1241 pw->pw_name, _PATH_NOLOGIN);
1242 while (fgets(buf, sizeof(buf), f))
1250 /* Set login name, uid, gid, and groups. */
1252 do_setusercontext(struct passwd *pw)
1255 if (getuid() == 0 || geteuid() == 0)
1256 #endif /* HAVE_CYGWIN */
1259 #ifdef HAVE_SETPCRED
1260 if (setpcred(pw->pw_name, (char **)NULL) == -1)
1261 fatal("Failed to set process credentials");
1262 #endif /* HAVE_SETPCRED */
1263 #ifdef HAVE_LOGIN_CAP
1268 if (options.gss_authentication) {
1269 temporarily_use_uid(pw);
1270 ssh_gssapi_storecreds();
1275 if (options.use_pam) {
1279 # endif /* USE_PAM */
1280 if (setusercontext(lc, pw, pw->pw_uid,
1281 (LOGIN_SETALL & ~LOGIN_SETPATH)) < 0) {
1282 perror("unable to set user context");
1286 # if defined(HAVE_GETLUID) && defined(HAVE_SETLUID)
1287 /* Sets login uid for accounting */
1288 if (getluid() == -1 && setluid(pw->pw_uid) == -1)
1289 error("setluid: %s", strerror(errno));
1290 # endif /* defined(HAVE_GETLUID) && defined(HAVE_SETLUID) */
1292 if (setlogin(pw->pw_name) < 0)
1293 error("setlogin failed: %s", strerror(errno));
1294 if (setgid(pw->pw_gid) < 0) {
1298 /* Initialize the group list. */
1299 if (initgroups(pw->pw_name, pw->pw_gid) < 0) {
1300 perror("initgroups");
1305 if (options.gss_authentication) {
1306 temporarily_use_uid(pw);
1307 ssh_gssapi_storecreds();
1313 * PAM credentials may take the form of supplementary groups.
1314 * These will have been wiped by the above initgroups() call.
1315 * Reestablish them here.
1317 if (options.use_pam) {
1321 # endif /* USE_PAM */
1322 # if defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY)
1323 irix_setusercontext(pw);
1324 # endif /* defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) */
1328 #if defined(HAVE_LIBIAF) && !defined(BROKEN_LIBIAF)
1329 if (set_id(pw->pw_name) != 0) {
1332 #endif /* HAVE_LIBIAF && !BROKEN_LIBIAF */
1333 /* Permanently switch to the desired uid. */
1334 permanently_set_uid(pw);
1341 if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid)
1342 fatal("Failed to set uids to %u.", (u_int) pw->pw_uid);
1346 do_pwchange(Session *s)
1349 fprintf(stderr, "WARNING: Your password has expired.\n");
1350 if (s->ttyfd != -1) {
1352 "You must change your password now and login again!\n");
1353 #ifdef PASSWD_NEEDS_USERNAME
1354 execl(_PATH_PASSWD_PROG, "passwd", s->pw->pw_name,
1357 execl(_PATH_PASSWD_PROG, "passwd", (char *)NULL);
1362 "Password change required but no TTY available.\n");
1368 launch_login(struct passwd *pw, const char *hostname)
1370 /* Launch login(1). */
1372 execl(LOGIN_PROGRAM, "login", "-h", hostname,
1373 #ifdef xxxLOGIN_NEEDS_TERM
1374 (s->term ? s->term : "unknown"),
1375 #endif /* LOGIN_NEEDS_TERM */
1376 #ifdef LOGIN_NO_ENDOPT
1377 "-p", "-f", pw->pw_name, (char *)NULL);
1379 "-p", "-f", "--", pw->pw_name, (char *)NULL);
1382 /* Login couldn't be executed, die. */
1389 child_close_fds(void)
1393 if (packet_get_connection_in() == packet_get_connection_out())
1394 close(packet_get_connection_in());
1396 close(packet_get_connection_in());
1397 close(packet_get_connection_out());
1400 * Close all descriptors related to channels. They will still remain
1401 * open in the parent.
1403 /* XXX better use close-on-exec? -markus */
1404 channel_close_all();
1407 * Close any extra file descriptors. Note that there may still be
1408 * descriptors left by system functions. They will be closed later.
1413 * Close any extra open file descriptors so that we don't have them
1414 * hanging around in clients. Note that we want to do this after
1415 * initgroups, because at least on Solaris 2.3 it leaves file
1418 for (i = 3; i < 64; i++)
1423 * Performs common processing for the child, such as setting up the
1424 * environment, closing extra file descriptors, setting the user and group
1425 * ids, and executing the command or shell.
1428 do_child(Session *s, const char *command)
1430 extern char **environ;
1433 const char *shell, *shell0, *hostname = NULL;
1434 struct passwd *pw = s->pw;
1436 /* remove hostkey from the child's memory */
1437 destroy_sensitive_data();
1439 /* Force a password change */
1440 if (s->authctxt->force_pwchange) {
1441 do_setusercontext(pw);
1447 /* login(1) is only called if we execute the login shell */
1448 if (options.use_login && command != NULL)
1449 options.use_login = 0;
1452 cray_setup(pw->pw_uid, pw->pw_name, command);
1453 #endif /* _UNICOS */
1456 * Login(1) does this as well, and it needs uid 0 for the "-h"
1457 * switch, so we let login(1) to this for us.
1459 if (!options.use_login) {
1461 session_setup_sia(pw, s->ttyfd == -1 ? NULL : s->tty);
1462 if (!check_quietlogin(s, command))
1464 #else /* HAVE_OSF_SIA */
1465 /* When PAM is enabled we rely on it to do the nologin check */
1466 if (!options.use_pam)
1468 do_setusercontext(pw);
1470 * PAM session modules in do_setusercontext may have
1471 * generated messages, so if this in an interactive
1472 * login then display them too.
1474 if (!check_quietlogin(s, command))
1476 #endif /* HAVE_OSF_SIA */
1480 if (options.use_pam && !options.use_login && !is_pam_session_open()) {
1481 debug3("PAM session not opened, exiting");
1488 * Get the shell from the password data. An empty shell field is
1489 * legal, and means /bin/sh.
1491 shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
1494 * Make sure $SHELL points to the shell from the password file,
1495 * even if shell is overridden from login.conf
1497 env = do_setup_env(s, shell);
1499 #ifdef HAVE_LOGIN_CAP
1500 shell = login_getcapstr(lc, "shell", (char *)shell, (char *)shell);
1503 /* we have to stash the hostname before we close our socket. */
1504 if (options.use_login)
1505 hostname = get_remote_name_or_ip(utmp_len,
1508 * Close the connection descriptors; note that this is the child, and
1509 * the server will still have the socket open, and it is important
1510 * that we do not shutdown it. Note that the descriptors cannot be
1511 * closed before building the environment, as we call
1512 * get_remote_ipaddr there.
1517 * Must take new environment into use so that .ssh/rc,
1518 * /etc/ssh/sshrc and xauth are run in the proper environment.
1522 #if defined(KRB5) && defined(USE_AFS)
1524 * At this point, we check to see if AFS is active and if we have
1525 * a valid Kerberos 5 TGT. If so, it seems like a good idea to see
1526 * if we can (and need to) extend the ticket into an AFS token. If
1527 * we don't do this, we run into potential problems if the user's
1528 * home directory is in AFS and it's not world-readable.
1531 if (options.kerberos_get_afs_token && k_hasafs() &&
1532 (s->authctxt->krb5_ctx != NULL)) {
1535 debug("Getting AFS token");
1539 if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0)
1540 krb5_afslog(s->authctxt->krb5_ctx,
1541 s->authctxt->krb5_fwd_ccache, cell, NULL);
1543 krb5_afslog_home(s->authctxt->krb5_ctx,
1544 s->authctxt->krb5_fwd_ccache, NULL, NULL, pw->pw_dir);
1548 /* Change current directory to the user's home directory. */
1549 if (chdir(pw->pw_dir) < 0) {
1550 fprintf(stderr, "Could not chdir to home directory %s: %s\n",
1551 pw->pw_dir, strerror(errno));
1552 #ifdef HAVE_LOGIN_CAP
1553 if (login_getcapbool(lc, "requirehome", 0))
1558 if (!options.use_login)
1559 do_rc_files(s, shell);
1561 /* restore SIGPIPE for child */
1562 signal(SIGPIPE, SIG_DFL);
1564 if (options.use_login) {
1565 launch_login(pw, hostname);
1569 /* Get the last component of the shell name. */
1570 if ((shell0 = strrchr(shell, '/')) != NULL)
1576 * If we have no command, execute the shell. In this case, the shell
1577 * name to be passed in argv[0] is preceded by '-' to indicate that
1578 * this is a login shell.
1583 /* Start the shell. Set initial character to '-'. */
1586 if (strlcpy(argv0 + 1, shell0, sizeof(argv0) - 1)
1587 >= sizeof(argv0) - 1) {
1593 /* Execute the shell. */
1596 execve(shell, argv, env);
1598 /* Executing the shell failed. */
1603 * Execute the command using the user's shell. This uses the -c
1604 * option to execute the command.
1606 argv[0] = (char *) shell0;
1608 argv[2] = (char *) command;
1610 execve(shell, argv, env);
1619 static int did_init = 0;
1621 debug("session_new: init");
1622 for (i = 0; i < MAX_SESSIONS; i++) {
1623 sessions[i].used = 0;
1627 for (i = 0; i < MAX_SESSIONS; i++) {
1628 Session *s = &sessions[i];
1630 memset(s, 0, sizeof(*s));
1636 s->x11_chanids = NULL;
1637 debug("session_new: session %d", i);
1648 for (i = 0; i < MAX_SESSIONS; i++) {
1649 Session *s = &sessions[i];
1650 debug("dump: used %d session %d %p channel %d pid %ld",
1660 session_open(Authctxt *authctxt, int chanid)
1662 Session *s = session_new();
1663 debug("session_open: channel %d", chanid);
1665 error("no more sessions");
1668 s->authctxt = authctxt;
1669 s->pw = authctxt->pw;
1670 if (s->pw == NULL || !authctxt->valid)
1671 fatal("no user for session %d", s->self);
1672 debug("session_open: session %d: link with channel %d", s->self, chanid);
1678 session_by_tty(char *tty)
1681 for (i = 0; i < MAX_SESSIONS; i++) {
1682 Session *s = &sessions[i];
1683 if (s->used && s->ttyfd != -1 && strcmp(s->tty, tty) == 0) {
1684 debug("session_by_tty: session %d tty %s", i, tty);
1688 debug("session_by_tty: unknown tty %.100s", tty);
1694 session_by_channel(int id)
1697 for (i = 0; i < MAX_SESSIONS; i++) {
1698 Session *s = &sessions[i];
1699 if (s->used && s->chanid == id) {
1700 debug("session_by_channel: session %d channel %d", i, id);
1704 debug("session_by_channel: unknown channel %d", id);
1710 session_by_x11_channel(int id)
1714 for (i = 0; i < MAX_SESSIONS; i++) {
1715 Session *s = &sessions[i];
1717 if (s->x11_chanids == NULL || !s->used)
1719 for (j = 0; s->x11_chanids[j] != -1; j++) {
1720 if (s->x11_chanids[j] == id) {
1721 debug("session_by_x11_channel: session %d "
1722 "channel %d", s->self, id);
1727 debug("session_by_x11_channel: unknown channel %d", id);
1733 session_by_pid(pid_t pid)
1736 debug("session_by_pid: pid %ld", (long)pid);
1737 for (i = 0; i < MAX_SESSIONS; i++) {
1738 Session *s = &sessions[i];
1739 if (s->used && s->pid == pid)
1742 error("session_by_pid: unknown pid %ld", (long)pid);
1748 session_window_change_req(Session *s)
1750 s->col = packet_get_int();
1751 s->row = packet_get_int();
1752 s->xpixel = packet_get_int();
1753 s->ypixel = packet_get_int();
1755 pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1760 session_pty_req(Session *s)
1766 debug("Allocating a pty not permitted for this authentication.");
1769 if (s->ttyfd != -1) {
1770 packet_disconnect("Protocol error: you already have a pty.");
1774 s->term = packet_get_string(&len);
1777 s->col = packet_get_int();
1778 s->row = packet_get_int();
1780 s->row = packet_get_int();
1781 s->col = packet_get_int();
1783 s->xpixel = packet_get_int();
1784 s->ypixel = packet_get_int();
1786 if (strcmp(s->term, "") == 0) {
1791 /* Allocate a pty and open it. */
1792 debug("Allocating pty.");
1793 if (!PRIVSEP(pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty)))) {
1799 error("session_pty_req: session %d alloc failed", s->self);
1802 debug("session_pty_req: session %d alloc %s", s->self, s->tty);
1804 /* for SSH1 the tty modes length is not given */
1806 n_bytes = packet_remaining();
1807 tty_parse_modes(s->ttyfd, &n_bytes);
1810 pty_setowner(s->pw, s->tty);
1812 /* Set window size from the packet. */
1813 pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1816 session_proctitle(s);
1821 session_subsystem_req(Session *s)
1826 char *cmd, *subsys = packet_get_string(&len);
1830 logit("subsystem request for %.100s", subsys);
1832 for (i = 0; i < options.num_subsystems; i++) {
1833 if (strcmp(subsys, options.subsystem_name[i]) == 0) {
1834 cmd = options.subsystem_command[i];
1835 if (stat(cmd, &st) < 0) {
1836 error("subsystem: cannot stat %s: %s", cmd,
1840 debug("subsystem: exec() %s", cmd);
1841 s->is_subsystem = 1;
1849 logit("subsystem request for %.100s failed, subsystem not found",
1857 session_x11_req(Session *s)
1861 if (s->auth_proto != NULL || s->auth_data != NULL) {
1862 error("session_x11_req: session %d: "
1863 "x11 forwarding already active", s->self);
1866 s->single_connection = packet_get_char();
1867 s->auth_proto = packet_get_string(NULL);
1868 s->auth_data = packet_get_string(NULL);
1869 s->screen = packet_get_int();
1872 success = session_setup_x11fwd(s);
1874 xfree(s->auth_proto);
1875 xfree(s->auth_data);
1876 s->auth_proto = NULL;
1877 s->auth_data = NULL;
1883 session_shell_req(Session *s)
1891 session_exec_req(Session *s)
1894 char *command = packet_get_string(&len);
1896 do_exec(s, command);
1902 session_break_req(Session *s)
1905 packet_get_int(); /* ignored */
1908 if (s->ttyfd == -1 ||
1909 tcsendbreak(s->ttyfd, 0) < 0)
1915 session_env_req(Session *s)
1918 u_int name_len, val_len, i;
1920 name = packet_get_string(&name_len);
1921 val = packet_get_string(&val_len);
1924 /* Don't set too many environment variables */
1925 if (s->num_env > 128) {
1926 debug2("Ignoring env request %s: too many env vars", name);
1930 for (i = 0; i < options.num_accept_env; i++) {
1931 if (match_pattern(name, options.accept_env[i])) {
1932 debug2("Setting env %d: %s=%s", s->num_env, name, val);
1933 s->env = xrealloc(s->env, sizeof(*s->env) *
1935 s->env[s->num_env].name = name;
1936 s->env[s->num_env].val = val;
1941 debug2("Ignoring env request %s: disallowed name", name);
1950 session_auth_agent_req(Session *s)
1952 static int called = 0;
1954 if (no_agent_forwarding_flag) {
1955 debug("session_auth_agent_req: no_agent_forwarding_flag");
1962 return auth_input_request_forwarding(s->pw);
1967 session_input_channel_req(Channel *c, const char *rtype)
1972 if ((s = session_by_channel(c->self)) == NULL) {
1973 logit("session_input_channel_req: no session %d req %.100s",
1977 debug("session_input_channel_req: session %d req %s", s->self, rtype);
1980 * a session is in LARVAL state until a shell, a command
1981 * or a subsystem is executed
1983 if (c->type == SSH_CHANNEL_LARVAL) {
1984 if (strcmp(rtype, "shell") == 0) {
1985 success = session_shell_req(s);
1986 } else if (strcmp(rtype, "exec") == 0) {
1987 success = session_exec_req(s);
1988 } else if (strcmp(rtype, "pty-req") == 0) {
1989 success = session_pty_req(s);
1990 } else if (strcmp(rtype, "x11-req") == 0) {
1991 success = session_x11_req(s);
1992 } else if (strcmp(rtype, "auth-agent-req@openssh.com") == 0) {
1993 success = session_auth_agent_req(s);
1994 } else if (strcmp(rtype, "subsystem") == 0) {
1995 success = session_subsystem_req(s);
1996 } else if (strcmp(rtype, "env") == 0) {
1997 success = session_env_req(s);
2000 if (strcmp(rtype, "window-change") == 0) {
2001 success = session_window_change_req(s);
2002 } else if (strcmp(rtype, "break") == 0) {
2003 success = session_break_req(s);
2010 session_set_fds(Session *s, int fdin, int fdout, int fderr)
2013 fatal("session_set_fds: called for proto != 2.0");
2015 * now that have a child and a pipe to the child,
2016 * we can activate our channel and register the fd's
2018 if (s->chanid == -1)
2019 fatal("no channel for session %d", s->self);
2020 channel_set_fds(s->chanid,
2022 fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ,
2024 CHAN_SES_WINDOW_DEFAULT);
2028 * Function to perform pty cleanup. Also called if we get aborted abnormally
2029 * (e.g., due to a dropped connection).
2032 session_pty_cleanup2(Session *s)
2035 error("session_pty_cleanup: no session");
2041 debug("session_pty_cleanup: session %d release %s", s->self, s->tty);
2043 /* Record that the user has logged out. */
2045 record_logout(s->pid, s->tty, s->pw->pw_name);
2047 /* Release the pseudo-tty. */
2049 pty_release(s->tty);
2052 * Close the server side of the socket pairs. We must do this after
2053 * the pty cleanup, so that another process doesn't get this pty
2054 * while we're still cleaning up.
2056 if (close(s->ptymaster) < 0)
2057 error("close(s->ptymaster/%d): %s", s->ptymaster, strerror(errno));
2059 /* unlink pty from session */
2064 session_pty_cleanup(Session *s)
2066 PRIVSEP(session_pty_cleanup2(s));
2072 #define SSH_SIG(x) if (sig == SIG ## x) return #x
2087 return "SIG@openssh.com";
2091 session_close_x11(int id)
2095 if ((c = channel_by_id(id)) == NULL) {
2096 debug("session_close_x11: x11 channel %d missing", id);
2098 /* Detach X11 listener */
2099 debug("session_close_x11: detach x11 channel %d", id);
2100 channel_cancel_cleanup(id);
2101 if (c->ostate != CHAN_OUTPUT_CLOSED)
2107 session_close_single_x11(int id, void *arg)
2112 debug3("session_close_single_x11: channel %d", id);
2113 channel_cancel_cleanup(id);
2114 if ((s = session_by_x11_channel(id)) == NULL)
2115 fatal("session_close_single_x11: no x11 channel %d", id);
2116 for (i = 0; s->x11_chanids[i] != -1; i++) {
2117 debug("session_close_single_x11: session %d: "
2118 "closing channel %d", s->self, s->x11_chanids[i]);
2120 * The channel "id" is already closing, but make sure we
2121 * close all of its siblings.
2123 if (s->x11_chanids[i] != id)
2124 session_close_x11(s->x11_chanids[i]);
2126 xfree(s->x11_chanids);
2127 s->x11_chanids = NULL;
2132 if (s->auth_proto) {
2133 xfree(s->auth_proto);
2134 s->auth_proto = NULL;
2137 xfree(s->auth_data);
2138 s->auth_data = NULL;
2140 if (s->auth_display) {
2141 xfree(s->auth_display);
2142 s->auth_display = NULL;
2147 session_exit_message(Session *s, int status)
2151 if ((c = channel_lookup(s->chanid)) == NULL)
2152 fatal("session_exit_message: session %d: no channel %d",
2153 s->self, s->chanid);
2154 debug("session_exit_message: session %d channel %d pid %ld",
2155 s->self, s->chanid, (long)s->pid);
2157 if (WIFEXITED(status)) {
2158 channel_request_start(s->chanid, "exit-status", 0);
2159 packet_put_int(WEXITSTATUS(status));
2161 } else if (WIFSIGNALED(status)) {
2162 channel_request_start(s->chanid, "exit-signal", 0);
2163 packet_put_cstring(sig2name(WTERMSIG(status)));
2165 packet_put_char(WCOREDUMP(status));
2166 #else /* WCOREDUMP */
2168 #endif /* WCOREDUMP */
2169 packet_put_cstring("");
2170 packet_put_cstring("");
2173 /* Some weird exit cause. Just exit. */
2174 packet_disconnect("wait returned status %04x.", status);
2177 /* disconnect channel */
2178 debug("session_exit_message: release channel %d", s->chanid);
2181 * Adjust cleanup callback attachment to send close messages when
2182 * the channel gets EOF. The session will be then be closed
2183 * by session_close_by_channel when the childs close their fds.
2185 channel_register_cleanup(c->self, session_close_by_channel, 1);
2188 * emulate a write failure with 'chan_write_failed', nobody will be
2189 * interested in data we write.
2190 * Note that we must not call 'chan_read_failed', since there could
2191 * be some more data waiting in the pipe.
2193 if (c->ostate != CHAN_OUTPUT_CLOSED)
2194 chan_write_failed(c);
2198 session_close(Session *s)
2202 debug("session_close: session %d pid %ld", s->self, (long)s->pid);
2204 session_pty_cleanup(s);
2210 xfree(s->x11_chanids);
2211 if (s->auth_display)
2212 xfree(s->auth_display);
2214 xfree(s->auth_data);
2216 xfree(s->auth_proto);
2218 for (i = 0; i < s->num_env; i++) {
2219 xfree(s->env[i].name);
2220 xfree(s->env[i].val);
2224 session_proctitle(s);
2228 session_close_by_pid(pid_t pid, int status)
2230 Session *s = session_by_pid(pid);
2232 debug("session_close_by_pid: no session for pid %ld",
2236 if (s->chanid != -1)
2237 session_exit_message(s, status);
2239 session_pty_cleanup(s);
2244 * this is called when a channel dies before
2245 * the session 'child' itself dies
2248 session_close_by_channel(int id, void *arg)
2250 Session *s = session_by_channel(id);
2254 debug("session_close_by_channel: no session for id %d", id);
2257 debug("session_close_by_channel: channel %d child %ld",
2260 debug("session_close_by_channel: channel %d: has child", id);
2262 * delay detach of session, but release pty, since
2263 * the fd's to the child are already closed
2266 session_pty_cleanup(s);
2269 /* detach by removing callback */
2270 channel_cancel_cleanup(s->chanid);
2272 /* Close any X11 listeners associated with this session */
2273 if (s->x11_chanids != NULL) {
2274 for (i = 0; s->x11_chanids[i] != -1; i++) {
2275 session_close_x11(s->x11_chanids[i]);
2276 s->x11_chanids[i] = -1;
2285 session_destroy_all(void (*closefunc)(Session *))
2288 for (i = 0; i < MAX_SESSIONS; i++) {
2289 Session *s = &sessions[i];
2291 if (closefunc != NULL)
2300 session_tty_list(void)
2302 static char buf[1024];
2307 for (i = 0; i < MAX_SESSIONS; i++) {
2308 Session *s = &sessions[i];
2309 if (s->used && s->ttyfd != -1) {
2311 if (strncmp(s->tty, "/dev/", 5) != 0) {
2312 cp = strrchr(s->tty, '/');
2313 cp = (cp == NULL) ? s->tty : cp + 1;
2318 strlcat(buf, ",", sizeof buf);
2319 strlcat(buf, cp, sizeof buf);
2323 strlcpy(buf, "notty", sizeof buf);
2328 session_proctitle(Session *s)
2331 error("no user for session %d", s->self);
2333 setproctitle("%s@%s", s->pw->pw_name, session_tty_list());
2337 session_setup_x11fwd(Session *s)
2340 char display[512], auth_display[512];
2341 char hostname[MAXHOSTNAMELEN];
2344 if (no_x11_forwarding_flag) {
2345 packet_send_debug("X11 forwarding disabled in user configuration file.");
2348 if (!options.x11_forwarding) {
2349 debug("X11 forwarding disabled in server configuration file.");
2352 if (!options.xauth_location ||
2353 (stat(options.xauth_location, &st) == -1)) {
2354 packet_send_debug("No xauth program; cannot forward with spoofing.");
2357 if (options.use_login) {
2358 packet_send_debug("X11 forwarding disabled; "
2359 "not compatible with UseLogin=yes.");
2362 if (s->display != NULL) {
2363 debug("X11 display already set.");
2366 if (x11_create_display_inet(options.x11_display_offset,
2367 options.x11_use_localhost, s->single_connection,
2368 &s->display_number, &s->x11_chanids) == -1) {
2369 debug("x11_create_display_inet failed.");
2372 for (i = 0; s->x11_chanids[i] != -1; i++) {
2373 channel_register_cleanup(s->x11_chanids[i],
2374 session_close_single_x11, 0);
2377 /* Set up a suitable value for the DISPLAY variable. */
2378 if (gethostname(hostname, sizeof(hostname)) < 0)
2379 fatal("gethostname: %.100s", strerror(errno));
2381 * auth_display must be used as the displayname when the
2382 * authorization entry is added with xauth(1). This will be
2383 * different than the DISPLAY string for localhost displays.
2385 if (options.x11_use_localhost) {
2386 snprintf(display, sizeof display, "localhost:%u.%u",
2387 s->display_number, s->screen);
2388 snprintf(auth_display, sizeof auth_display, "unix:%u.%u",
2389 s->display_number, s->screen);
2390 s->display = xstrdup(display);
2391 s->auth_display = xstrdup(auth_display);
2393 #ifdef IPADDR_IN_DISPLAY
2395 struct in_addr my_addr;
2397 he = gethostbyname(hostname);
2399 error("Can't get IP address for X11 DISPLAY.");
2400 packet_send_debug("Can't get IP address for X11 DISPLAY.");
2403 memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr));
2404 snprintf(display, sizeof display, "%.50s:%u.%u", inet_ntoa(my_addr),
2405 s->display_number, s->screen);
2407 snprintf(display, sizeof display, "%.400s:%u.%u", hostname,
2408 s->display_number, s->screen);
2410 s->display = xstrdup(display);
2411 s->auth_display = xstrdup(display);
2418 do_authenticated2(Authctxt *authctxt)
2420 server_loop2(authctxt);
2424 do_cleanup(Authctxt *authctxt)
2426 static int called = 0;
2428 debug("do_cleanup");
2430 /* no cleanup if we're in the child for login shell */
2434 /* avoid double cleanup */
2439 if (authctxt == NULL)
2442 if (options.kerberos_ticket_cleanup &&
2444 krb5_cleanup_proc(authctxt);
2448 if (compat20 && options.gss_cleanup_creds)
2449 ssh_gssapi_cleanup_creds();
2453 if (options.use_pam) {
2455 sshpam_thread_cleanup();
2459 /* remove agent socket */
2460 auth_sock_cleanup_proc(authctxt->pw);
2463 * Cleanup ptys/utmp only if privsep is disabled,
2464 * or if running in monitor.
2466 if (!use_privsep || mm_is_monitor())
2467 session_destroy_all(session_pty_cleanup2);