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.
37 #include <sys/types.h>
38 #ifdef HAVE_SYS_STAT_H
39 # include <sys/stat.h>
62 #include "auth-options.h"
63 #include "pathnames.h"
67 #include "serverloop.h"
71 #include "monitor_wrap.h"
73 #if defined(KRB5) && defined(USE_AFS)
83 Session *session_new(void);
84 void session_set_fds(Session *, int, int, int);
85 void session_pty_cleanup(Session *);
86 void session_proctitle(Session *);
87 int session_setup_x11fwd(Session *);
88 void do_exec_pty(Session *, const char *);
89 void do_exec_no_pty(Session *, const char *);
90 void do_exec(Session *, const char *);
91 void do_login(Session *, const char *);
92 #ifdef LOGIN_NEEDS_UTMPX
93 static void do_pre_login(Session *s);
95 void do_child(Session *, const char *);
97 int check_quietlogin(Session *, const char *);
99 static void do_authenticated1(Authctxt *);
100 static void do_authenticated2(Authctxt *);
102 static int session_pty_req(Session *);
105 extern ServerOptions options;
106 extern char *__progname;
107 extern int log_stderr;
108 extern int debug_flag;
109 extern u_int utmp_len;
110 extern int startup_pipe;
111 extern void destroy_sensitive_data(void);
112 extern Buffer loginmsg;
114 /* original command from peer. */
115 const char *original_command = NULL;
118 #define MAX_SESSIONS 10
119 Session sessions[MAX_SESSIONS];
121 #ifdef HAVE_LOGIN_CAP
125 static int is_child = 0;
127 /* Name and directory of socket for authentication agent forwarding. */
128 static char *auth_sock_name = NULL;
129 static char *auth_sock_dir = NULL;
131 /* removes the agent forwarding socket */
134 auth_sock_cleanup_proc(struct passwd *pw)
136 if (auth_sock_name != NULL) {
137 temporarily_use_uid(pw);
138 unlink(auth_sock_name);
139 rmdir(auth_sock_dir);
140 auth_sock_name = NULL;
146 auth_input_request_forwarding(struct passwd * pw)
150 struct sockaddr_un sunaddr;
152 if (auth_sock_name != NULL) {
153 error("authentication forwarding requested twice.");
157 /* Temporarily drop privileged uid for mkdir/bind. */
158 temporarily_use_uid(pw);
160 /* Allocate a buffer for the socket name, and format the name. */
161 auth_sock_name = xmalloc(MAXPATHLEN);
162 auth_sock_dir = xmalloc(MAXPATHLEN);
163 strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN);
165 /* Create private directory for socket */
166 if (mkdtemp(auth_sock_dir) == NULL) {
167 packet_send_debug("Agent forwarding disabled: "
168 "mkdtemp() failed: %.100s", strerror(errno));
170 xfree(auth_sock_name);
171 xfree(auth_sock_dir);
172 auth_sock_name = NULL;
173 auth_sock_dir = NULL;
176 snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%ld",
177 auth_sock_dir, (long) getpid());
179 /* Create the socket. */
180 sock = socket(AF_UNIX, SOCK_STREAM, 0);
182 packet_disconnect("socket: %.100s", strerror(errno));
184 /* Bind it to the name. */
185 memset(&sunaddr, 0, sizeof(sunaddr));
186 sunaddr.sun_family = AF_UNIX;
187 strlcpy(sunaddr.sun_path, auth_sock_name, sizeof(sunaddr.sun_path));
189 if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0)
190 packet_disconnect("bind: %.100s", strerror(errno));
192 /* Restore the privileged uid. */
195 /* Start listening on the socket. */
196 if (listen(sock, SSH_LISTEN_BACKLOG) < 0)
197 packet_disconnect("listen: %.100s", strerror(errno));
199 /* Allocate a channel for the authentication agent socket. */
200 nc = channel_new("auth socket",
201 SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1,
202 CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
203 0, "auth socket", 1);
204 strlcpy(nc->path, auth_sock_name, sizeof(nc->path));
209 display_loginmsg(void)
211 if (buffer_len(&loginmsg) > 0) {
212 buffer_append(&loginmsg, "\0", 1);
213 printf("%s", (char *)buffer_ptr(&loginmsg));
214 buffer_clear(&loginmsg);
219 do_authenticated(Authctxt *authctxt)
221 setproctitle("%s", authctxt->pw->pw_name);
223 /* setup the channel layer */
224 if (!no_port_forwarding_flag && options.allow_tcp_forwarding)
225 channel_permit_all_opens();
228 do_authenticated2(authctxt);
230 do_authenticated1(authctxt);
232 do_cleanup(authctxt);
236 * Prepares for an interactive session. This is called after the user has
237 * been successfully authenticated. During this message exchange, pseudo
238 * terminals are allocated, X11, TCP/IP, and authentication agent forwardings
239 * are requested, etc.
242 do_authenticated1(Authctxt *authctxt)
246 int success, type, screen_flag;
247 int enable_compression_after_reply = 0;
248 u_int proto_len, data_len, dlen, compression_level = 0;
252 error("no more sessions");
255 s->authctxt = authctxt;
256 s->pw = authctxt->pw;
259 * We stay in this loop until the client requests to execute a shell
265 /* Get a packet from the client. */
266 type = packet_read();
268 /* Process the packet. */
270 case SSH_CMSG_REQUEST_COMPRESSION:
271 compression_level = packet_get_int();
273 if (compression_level < 1 || compression_level > 9) {
274 packet_send_debug("Received invalid compression level %d.",
278 if (options.compression == COMP_NONE) {
279 debug2("compression disabled");
282 /* Enable compression after we have responded with SUCCESS. */
283 enable_compression_after_reply = 1;
287 case SSH_CMSG_REQUEST_PTY:
288 success = session_pty_req(s);
291 case SSH_CMSG_X11_REQUEST_FORWARDING:
292 s->auth_proto = packet_get_string(&proto_len);
293 s->auth_data = packet_get_string(&data_len);
295 screen_flag = packet_get_protocol_flags() &
296 SSH_PROTOFLAG_SCREEN_NUMBER;
297 debug2("SSH_PROTOFLAG_SCREEN_NUMBER: %d", screen_flag);
299 if (packet_remaining() == 4) {
301 debug2("Buggy client: "
302 "X11 screen flag missing");
303 s->screen = packet_get_int();
308 success = session_setup_x11fwd(s);
310 xfree(s->auth_proto);
312 s->auth_proto = NULL;
317 case SSH_CMSG_AGENT_REQUEST_FORWARDING:
318 if (no_agent_forwarding_flag || compat13) {
319 debug("Authentication agent forwarding not permitted for this authentication.");
322 debug("Received authentication agent forwarding request.");
323 success = auth_input_request_forwarding(s->pw);
326 case SSH_CMSG_PORT_FORWARD_REQUEST:
327 if (no_port_forwarding_flag) {
328 debug("Port forwarding not permitted for this authentication.");
331 if (!options.allow_tcp_forwarding) {
332 debug("Port forwarding not permitted.");
335 debug("Received TCP/IP port forwarding request.");
336 channel_input_port_forward_request(s->pw->pw_uid == 0, options.gateway_ports);
340 case SSH_CMSG_MAX_PACKET_SIZE:
341 if (packet_set_maxsize(packet_get_int()) > 0)
345 case SSH_CMSG_EXEC_SHELL:
346 case SSH_CMSG_EXEC_CMD:
347 if (type == SSH_CMSG_EXEC_CMD) {
348 command = packet_get_string(&dlen);
349 debug("Exec command '%.500s'", command);
361 * Any unknown messages in this phase are ignored,
362 * and a failure message is returned.
364 logit("Unknown packet type received after authentication: %d", type);
366 packet_start(success ? SSH_SMSG_SUCCESS : SSH_SMSG_FAILURE);
370 /* Enable compression now that we have replied if appropriate. */
371 if (enable_compression_after_reply) {
372 enable_compression_after_reply = 0;
373 packet_start_compression(compression_level);
379 * This is called to fork and execute a command when we have no tty. This
380 * will call do_child from the child, and server_loop from the parent after
381 * setting up file descriptors and such.
384 do_exec_no_pty(Session *s, const char *command)
389 int pin[2], pout[2], perr[2];
390 /* Allocate pipes for communicating with the program. */
391 if (pipe(pin) < 0 || pipe(pout) < 0 || pipe(perr) < 0)
392 packet_disconnect("Could not create pipes: %.100s",
394 #else /* USE_PIPES */
395 int inout[2], err[2];
396 /* Uses socket pairs to communicate with the program. */
397 if (socketpair(AF_UNIX, SOCK_STREAM, 0, inout) < 0 ||
398 socketpair(AF_UNIX, SOCK_STREAM, 0, err) < 0)
399 packet_disconnect("Could not create socket pairs: %.100s",
401 #endif /* USE_PIPES */
403 fatal("do_exec_no_pty: no session");
405 session_proctitle(s);
408 if (options.use_pam && !use_privsep)
412 /* Fork the child. */
413 if ((pid = fork()) == 0) {
416 /* Child. Reinitialize the log since the pid has changed. */
417 log_init(__progname, options.log_level, options.log_facility, log_stderr);
420 * Create a new session and process group since the 4.4BSD
421 * setlogin() affects the entire process group.
424 error("setsid failed: %.100s", strerror(errno));
428 * Redirect stdin. We close the parent side of the socket
429 * pair, and make the child side the standard input.
432 if (dup2(pin[0], 0) < 0)
433 perror("dup2 stdin");
436 /* Redirect stdout. */
438 if (dup2(pout[1], 1) < 0)
439 perror("dup2 stdout");
442 /* Redirect stderr. */
444 if (dup2(perr[1], 2) < 0)
445 perror("dup2 stderr");
447 #else /* USE_PIPES */
449 * Redirect stdin, stdout, and stderr. Stdin and stdout will
450 * use the same socket, as some programs (particularly rdist)
451 * seem to depend on it.
455 if (dup2(inout[0], 0) < 0) /* stdin */
456 perror("dup2 stdin");
457 if (dup2(inout[0], 1) < 0) /* stdout. Note: same socket as stdin. */
458 perror("dup2 stdout");
459 if (dup2(err[0], 2) < 0) /* stderr */
460 perror("dup2 stderr");
461 #endif /* USE_PIPES */
464 cray_init_job(s->pw); /* set up cray jid and tmpdir */
467 /* Do processing for the child (exec command etc). */
468 do_child(s, command);
472 signal(WJSIGNAL, cray_job_termination_handler);
476 cygwin_set_impersonation_token(INVALID_HANDLE_VALUE);
479 packet_disconnect("fork failed: %.100s", strerror(errno));
481 /* Set interactive/non-interactive mode. */
482 packet_set_interactive(s->display != NULL);
484 /* We are the parent. Close the child sides of the pipes. */
490 if (s->is_subsystem) {
494 session_set_fds(s, pin[1], pout[0], perr[0]);
496 /* Enter the interactive session. */
497 server_loop(pid, pin[1], pout[0], perr[0]);
498 /* server_loop has closed pin[1], pout[0], and perr[0]. */
500 #else /* USE_PIPES */
501 /* We are the parent. Close the child sides of the socket pairs. */
506 * Clear loginmsg, since it's the child's responsibility to display
507 * it to the user, otherwise multiple sessions may accumulate
508 * multiple copies of the login messages.
510 buffer_clear(&loginmsg);
513 * Enter the interactive session. Note: server_loop must be able to
514 * handle the case that fdin and fdout are the same.
517 session_set_fds(s, inout[1], inout[1], s->is_subsystem ? -1 : err[1]);
519 server_loop(pid, inout[1], inout[1], err[1]);
520 /* server_loop has closed inout[1] and err[1]. */
522 #endif /* USE_PIPES */
526 * This is called to fork and execute a command when we have a tty. This
527 * will call do_child from the child, and server_loop from the parent after
528 * setting up file descriptors, controlling tty, updating wtmp, utmp,
529 * lastlog, and other such operations.
532 do_exec_pty(Session *s, const char *command)
534 int fdout, ptyfd, ttyfd, ptymaster;
538 fatal("do_exec_pty: no session");
543 if (options.use_pam) {
544 do_pam_set_tty(s->tty);
550 /* Fork the child. */
551 if ((pid = fork()) == 0) {
554 /* Child. Reinitialize the log because the pid has changed. */
555 log_init(__progname, options.log_level, options.log_facility, log_stderr);
556 /* Close the master side of the pseudo tty. */
559 /* Make the pseudo tty our controlling tty. */
560 pty_make_controlling_tty(&ttyfd, s->tty);
562 /* Redirect stdin/stdout/stderr from the pseudo tty. */
563 if (dup2(ttyfd, 0) < 0)
564 error("dup2 stdin: %s", strerror(errno));
565 if (dup2(ttyfd, 1) < 0)
566 error("dup2 stdout: %s", strerror(errno));
567 if (dup2(ttyfd, 2) < 0)
568 error("dup2 stderr: %s", strerror(errno));
570 /* Close the extra descriptor for the pseudo tty. */
573 /* record login, etc. similar to login(1) */
575 if (!(options.use_login && command == NULL)) {
577 cray_init_job(s->pw); /* set up cray jid and tmpdir */
579 do_login(s, command);
581 # ifdef LOGIN_NEEDS_UTMPX
587 /* Do common processing for the child, such as execing the command. */
588 do_child(s, command);
592 signal(WJSIGNAL, cray_job_termination_handler);
596 cygwin_set_impersonation_token(INVALID_HANDLE_VALUE);
599 packet_disconnect("fork failed: %.100s", strerror(errno));
602 /* Parent. Close the slave side of the pseudo tty. */
606 * Create another descriptor of the pty master side for use as the
607 * standard input. We could use the original descriptor, but this
608 * simplifies code in server_loop. The descriptor is bidirectional.
612 packet_disconnect("dup #1 failed: %.100s", strerror(errno));
614 /* we keep a reference to the pty master */
615 ptymaster = dup(ptyfd);
617 packet_disconnect("dup #2 failed: %.100s", strerror(errno));
618 s->ptymaster = ptymaster;
620 /* Enter interactive session. */
621 packet_set_interactive(1);
623 session_set_fds(s, ptyfd, fdout, -1);
625 server_loop(pid, ptyfd, fdout, -1);
626 /* server_loop _has_ closed ptyfd and fdout. */
630 #ifdef LOGIN_NEEDS_UTMPX
632 do_pre_login(Session *s)
635 struct sockaddr_storage from;
636 pid_t pid = getpid();
639 * Get IP address of client. If the connection is not a socket, let
640 * the address be 0.0.0.0.
642 memset(&from, 0, sizeof(from));
643 fromlen = sizeof(from);
644 if (packet_connection_is_on_socket()) {
645 if (getpeername(packet_get_connection_in(),
646 (struct sockaddr *) & from, &fromlen) < 0) {
647 debug("getpeername: %.100s", strerror(errno));
652 record_utmp_only(pid, s->tty, s->pw->pw_name,
653 get_remote_name_or_ip(utmp_len, options.use_dns),
654 (struct sockaddr *)&from, fromlen);
659 * This is called to fork and execute a command. If another command is
660 * to be forced, execute that instead.
663 do_exec(Session *s, const char *command)
665 if (forced_command) {
666 original_command = command;
667 command = forced_command;
668 debug("Forced command '%.900s'", command);
671 #ifdef SSH_AUDIT_EVENTS
673 PRIVSEP(audit_run_command(command));
674 else if (s->ttyfd == -1) {
675 char *shell = s->pw->pw_shell;
677 if (shell[0] == '\0') /* empty shell means /bin/sh */
679 PRIVSEP(audit_run_command(shell));
684 do_exec_pty(s, command);
686 do_exec_no_pty(s, command);
688 original_command = NULL;
691 * Clear loginmsg: it's the child's responsibility to display
692 * it to the user, otherwise multiple sessions may accumulate
693 * multiple copies of the login messages.
695 buffer_clear(&loginmsg);
698 /* administrative, login(1)-like work */
700 do_login(Session *s, const char *command)
703 struct sockaddr_storage from;
704 struct passwd * pw = s->pw;
705 pid_t pid = getpid();
708 * Get IP address of client. If the connection is not a socket, let
709 * the address be 0.0.0.0.
711 memset(&from, 0, sizeof(from));
712 fromlen = sizeof(from);
713 if (packet_connection_is_on_socket()) {
714 if (getpeername(packet_get_connection_in(),
715 (struct sockaddr *) & from, &fromlen) < 0) {
716 debug("getpeername: %.100s", strerror(errno));
721 /* Record that there was a login on that tty from the remote host. */
723 record_login(pid, s->tty, pw->pw_name, pw->pw_uid,
724 get_remote_name_or_ip(utmp_len,
726 (struct sockaddr *)&from, fromlen);
730 * If password change is needed, do it now.
731 * This needs to occur before the ~/.hushlogin check.
733 if (options.use_pam && !use_privsep && s->authctxt->force_pwchange) {
736 s->authctxt->force_pwchange = 0;
737 /* XXX - signal [net] parent to enable forwardings */
741 if (check_quietlogin(s, command))
750 * Display the message of the day.
758 if (options.print_motd) {
759 #ifdef HAVE_LOGIN_CAP
760 f = fopen(login_getcapstr(lc, "welcome", "/etc/motd",
763 f = fopen("/etc/motd", "r");
766 while (fgets(buf, sizeof(buf), f))
775 * Check for quiet login, either .hushlogin or command given.
778 check_quietlogin(Session *s, const char *command)
781 struct passwd *pw = s->pw;
784 /* Return 1 if .hushlogin exists or a command given. */
787 snprintf(buf, sizeof(buf), "%.200s/.hushlogin", pw->pw_dir);
788 #ifdef HAVE_LOGIN_CAP
789 if (login_getcapbool(lc, "hushlogin", 0) || stat(buf, &st) >= 0)
792 if (stat(buf, &st) >= 0)
799 * Sets the value of the given variable in the environment. If the variable
800 * already exists, its value is overriden.
803 child_set_env(char ***envp, u_int *envsizep, const char *name,
811 * If we're passed an uninitialized list, allocate a single null
812 * entry before continuing.
814 if (*envp == NULL && *envsizep == 0) {
815 *envp = xmalloc(sizeof(char *));
821 * Find the slot where the value should be stored. If the variable
822 * already exists, we reuse the slot; otherwise we append a new slot
823 * at the end of the array, expanding if necessary.
826 namelen = strlen(name);
827 for (i = 0; env[i]; i++)
828 if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=')
831 /* Reuse the slot. */
834 /* New variable. Expand if necessary. */
836 if (i >= envsize - 1) {
838 fatal("child_set_env: too many env vars");
840 env = (*envp) = xrealloc(env, envsize * sizeof(char *));
843 /* Need to set the NULL pointer at end of array beyond the new slot. */
847 /* Allocate space and format the variable in the appropriate slot. */
848 env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1);
849 snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value);
853 * Reads environment variables from the given file and adds/overrides them
854 * into the environment. If the file does not exist, this does nothing.
855 * Otherwise, it must consist of empty lines, comments (line starts with '#')
856 * and assignments of the form name=value. No other forms are allowed.
859 read_environment_file(char ***env, u_int *envsize,
860 const char *filename)
867 f = fopen(filename, "r");
871 while (fgets(buf, sizeof(buf), f)) {
873 fatal("Too many lines in environment file %s", filename);
874 for (cp = buf; *cp == ' ' || *cp == '\t'; cp++)
876 if (!*cp || *cp == '#' || *cp == '\n')
878 if (strchr(cp, '\n'))
879 *strchr(cp, '\n') = '\0';
880 value = strchr(cp, '=');
882 fprintf(stderr, "Bad line %u in %.100s\n", lineno,
887 * Replace the equals sign by nul, and advance value to
892 child_set_env(env, envsize, cp, value);
897 #ifdef HAVE_ETC_DEFAULT_LOGIN
899 * Return named variable from specified environment, or NULL if not present.
902 child_get_env(char **env, const char *name)
908 for (i=0; env[i] != NULL; i++)
909 if (strncmp(name, env[i], len) == 0 && env[i][len] == '=')
910 return(env[i] + len + 1);
915 * Read /etc/default/login.
916 * We pick up the PATH (or SUPATH for root) and UMASK.
919 read_etc_default_login(char ***env, u_int *envsize, uid_t uid)
921 char **tmpenv = NULL, *var;
922 u_int i, tmpenvsize = 0;
926 * We don't want to copy the whole file to the child's environment,
927 * so we use a temporary environment and copy the variables we're
930 read_environment_file(&tmpenv, &tmpenvsize, "/etc/default/login");
936 var = child_get_env(tmpenv, "SUPATH");
938 var = child_get_env(tmpenv, "PATH");
940 child_set_env(env, envsize, "PATH", var);
942 if ((var = child_get_env(tmpenv, "UMASK")) != NULL)
943 if (sscanf(var, "%5lo", &mask) == 1)
946 for (i = 0; tmpenv[i] != NULL; i++)
950 #endif /* HAVE_ETC_DEFAULT_LOGIN */
953 copy_environment(char **source, char ***env, u_int *envsize)
955 char *var_name, *var_val;
961 for(i = 0; source[i] != NULL; i++) {
962 var_name = xstrdup(source[i]);
963 if ((var_val = strstr(var_name, "=")) == NULL) {
969 debug3("Copy environment: %s=%s", var_name, var_val);
970 child_set_env(env, envsize, var_name, var_val);
977 do_setup_env(Session *s, const char *shell)
981 char **env, *laddr, *path = NULL;
982 struct passwd *pw = s->pw;
984 /* Initialize the environment. */
986 env = xmalloc(envsize * sizeof(char *));
991 * The Windows environment contains some setting which are
992 * important for a running system. They must not be dropped.
997 p = fetch_windows_environment();
998 copy_environment(p, &env, &envsize);
999 free_windows_environment(p);
1004 /* Allow any GSSAPI methods that we've used to alter
1005 * the childs environment as they see fit
1007 ssh_gssapi_do_child(&env, &envsize);
1010 if (!options.use_login) {
1011 /* Set basic environment. */
1012 for (i = 0; i < s->num_env; i++)
1013 child_set_env(&env, &envsize, s->env[i].name,
1016 child_set_env(&env, &envsize, "USER", pw->pw_name);
1017 child_set_env(&env, &envsize, "LOGNAME", pw->pw_name);
1019 child_set_env(&env, &envsize, "LOGIN", pw->pw_name);
1021 child_set_env(&env, &envsize, "HOME", pw->pw_dir);
1022 #ifdef HAVE_LOGIN_CAP
1023 if (setusercontext(lc, pw, pw->pw_uid, LOGIN_SETPATH) < 0)
1024 child_set_env(&env, &envsize, "PATH", _PATH_STDPATH);
1026 child_set_env(&env, &envsize, "PATH", getenv("PATH"));
1027 #else /* HAVE_LOGIN_CAP */
1028 # ifndef HAVE_CYGWIN
1030 * There's no standard path on Windows. The path contains
1031 * important components pointing to the system directories,
1032 * needed for loading shared libraries. So the path better
1033 * remains intact here.
1035 # ifdef HAVE_ETC_DEFAULT_LOGIN
1036 read_etc_default_login(&env, &envsize, pw->pw_uid);
1037 path = child_get_env(env, "PATH");
1038 # endif /* HAVE_ETC_DEFAULT_LOGIN */
1039 if (path == NULL || *path == '\0') {
1040 child_set_env(&env, &envsize, "PATH",
1041 s->pw->pw_uid == 0 ?
1042 SUPERUSER_PATH : _PATH_STDPATH);
1044 # endif /* HAVE_CYGWIN */
1045 #endif /* HAVE_LOGIN_CAP */
1047 snprintf(buf, sizeof buf, "%.200s/%.50s",
1048 _PATH_MAILDIR, pw->pw_name);
1049 child_set_env(&env, &envsize, "MAIL", buf);
1051 /* Normal systems set SHELL by default. */
1052 child_set_env(&env, &envsize, "SHELL", shell);
1055 child_set_env(&env, &envsize, "TZ", getenv("TZ"));
1057 /* Set custom environment options from RSA authentication. */
1058 if (!options.use_login) {
1059 while (custom_environment) {
1060 struct envstring *ce = custom_environment;
1063 for (i = 0; str[i] != '=' && str[i]; i++)
1065 if (str[i] == '=') {
1067 child_set_env(&env, &envsize, str, str + i + 1);
1069 custom_environment = ce->next;
1075 /* SSH_CLIENT deprecated */
1076 snprintf(buf, sizeof buf, "%.50s %d %d",
1077 get_remote_ipaddr(), get_remote_port(), get_local_port());
1078 child_set_env(&env, &envsize, "SSH_CLIENT", buf);
1080 laddr = get_local_ipaddr(packet_get_connection_in());
1081 snprintf(buf, sizeof buf, "%.50s %d %.50s %d",
1082 get_remote_ipaddr(), get_remote_port(), laddr, get_local_port());
1084 child_set_env(&env, &envsize, "SSH_CONNECTION", buf);
1087 child_set_env(&env, &envsize, "SSH_TTY", s->tty);
1089 child_set_env(&env, &envsize, "TERM", s->term);
1091 child_set_env(&env, &envsize, "DISPLAY", s->display);
1092 if (original_command)
1093 child_set_env(&env, &envsize, "SSH_ORIGINAL_COMMAND",
1097 if (cray_tmpdir[0] != '\0')
1098 child_set_env(&env, &envsize, "TMPDIR", cray_tmpdir);
1099 #endif /* _UNICOS */
1102 * Since we clear KRB5CCNAME at startup, if it's set now then it
1103 * must have been set by a native authentication method (eg AIX or
1104 * SIA), so copy it to the child.
1109 if ((cp = getenv("KRB5CCNAME")) != NULL)
1110 child_set_env(&env, &envsize, "KRB5CCNAME", cp);
1117 if ((cp = getenv("AUTHSTATE")) != NULL)
1118 child_set_env(&env, &envsize, "AUTHSTATE", cp);
1119 read_environment_file(&env, &envsize, "/etc/environment");
1123 if (s->authctxt->krb5_ccname)
1124 child_set_env(&env, &envsize, "KRB5CCNAME",
1125 s->authctxt->krb5_ccname);
1129 * Pull in any environment variables that may have
1132 if (options.use_pam) {
1135 p = fetch_pam_child_environment();
1136 copy_environment(p, &env, &envsize);
1137 free_pam_environment(p);
1139 p = fetch_pam_environment();
1140 copy_environment(p, &env, &envsize);
1141 free_pam_environment(p);
1143 #endif /* USE_PAM */
1145 if (auth_sock_name != NULL)
1146 child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME,
1149 /* read $HOME/.ssh/environment. */
1150 if (options.permit_user_env && !options.use_login) {
1151 snprintf(buf, sizeof buf, "%.200s/.ssh/environment",
1152 strcmp(pw->pw_dir, "/") ? pw->pw_dir : "");
1153 read_environment_file(&env, &envsize, buf);
1156 /* dump the environment */
1157 fprintf(stderr, "Environment:\n");
1158 for (i = 0; env[i]; i++)
1159 fprintf(stderr, " %.200s\n", env[i]);
1165 * Run $HOME/.ssh/rc, /etc/ssh/sshrc, or xauth (whichever is found
1166 * first in this order).
1169 do_rc_files(Session *s, const char *shell)
1177 s->display != NULL && s->auth_proto != NULL && s->auth_data != NULL;
1179 /* ignore _PATH_SSH_USER_RC for subsystems */
1180 if (!s->is_subsystem && (stat(_PATH_SSH_USER_RC, &st) >= 0)) {
1181 snprintf(cmd, sizeof cmd, "%s -c '%s %s'",
1182 shell, _PATH_BSHELL, _PATH_SSH_USER_RC);
1184 fprintf(stderr, "Running %s\n", cmd);
1185 f = popen(cmd, "w");
1188 fprintf(f, "%s %s\n", s->auth_proto,
1192 fprintf(stderr, "Could not run %s\n",
1194 } else if (stat(_PATH_SSH_SYSTEM_RC, &st) >= 0) {
1196 fprintf(stderr, "Running %s %s\n", _PATH_BSHELL,
1197 _PATH_SSH_SYSTEM_RC);
1198 f = popen(_PATH_BSHELL " " _PATH_SSH_SYSTEM_RC, "w");
1201 fprintf(f, "%s %s\n", s->auth_proto,
1205 fprintf(stderr, "Could not run %s\n",
1206 _PATH_SSH_SYSTEM_RC);
1207 } else if (do_xauth && options.xauth_location != NULL) {
1208 /* Add authority data to .Xauthority if appropriate. */
1211 "Running %.500s remove %.100s\n",
1212 options.xauth_location, s->auth_display);
1214 "%.500s add %.100s %.100s %.100s\n",
1215 options.xauth_location, s->auth_display,
1216 s->auth_proto, s->auth_data);
1218 snprintf(cmd, sizeof cmd, "%s -q -",
1219 options.xauth_location);
1220 f = popen(cmd, "w");
1222 fprintf(f, "remove %s\n",
1224 fprintf(f, "add %s %s %s\n",
1225 s->auth_display, s->auth_proto,
1229 fprintf(stderr, "Could not run %s\n",
1236 do_nologin(struct passwd *pw)
1241 #ifdef HAVE_LOGIN_CAP
1242 if (!login_getcapbool(lc, "ignorenologin", 0) && pw->pw_uid)
1243 f = fopen(login_getcapstr(lc, "nologin", _PATH_NOLOGIN,
1244 _PATH_NOLOGIN), "r");
1247 f = fopen(_PATH_NOLOGIN, "r");
1250 /* /etc/nologin exists. Print its contents and exit. */
1251 logit("User %.100s not allowed because %s exists",
1252 pw->pw_name, _PATH_NOLOGIN);
1253 while (fgets(buf, sizeof(buf), f))
1261 /* Set login name, uid, gid, and groups. */
1263 do_setusercontext(struct passwd *pw)
1266 if (getuid() == 0 || geteuid() == 0)
1267 #endif /* HAVE_CYGWIN */
1270 #ifdef HAVE_SETPCRED
1271 if (setpcred(pw->pw_name, (char **)NULL) == -1)
1272 fatal("Failed to set process credentials");
1273 #endif /* HAVE_SETPCRED */
1274 #ifdef HAVE_LOGIN_CAP
1279 if (options.gss_authentication) {
1280 temporarily_use_uid(pw);
1281 ssh_gssapi_storecreds();
1286 if (options.use_pam) {
1290 # endif /* USE_PAM */
1291 if (setusercontext(lc, pw, pw->pw_uid,
1292 (LOGIN_SETALL & ~LOGIN_SETPATH)) < 0) {
1293 perror("unable to set user context");
1297 # if defined(HAVE_GETLUID) && defined(HAVE_SETLUID)
1298 /* Sets login uid for accounting */
1299 if (getluid() == -1 && setluid(pw->pw_uid) == -1)
1300 error("setluid: %s", strerror(errno));
1301 # endif /* defined(HAVE_GETLUID) && defined(HAVE_SETLUID) */
1303 if (setlogin(pw->pw_name) < 0)
1304 error("setlogin failed: %s", strerror(errno));
1305 if (setgid(pw->pw_gid) < 0) {
1309 /* Initialize the group list. */
1310 if (initgroups(pw->pw_name, pw->pw_gid) < 0) {
1311 perror("initgroups");
1316 if (options.gss_authentication) {
1317 temporarily_use_uid(pw);
1318 ssh_gssapi_storecreds();
1324 * PAM credentials may take the form of supplementary groups.
1325 * These will have been wiped by the above initgroups() call.
1326 * Reestablish them here.
1328 if (options.use_pam) {
1332 # endif /* USE_PAM */
1333 # if defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY)
1334 irix_setusercontext(pw);
1335 # endif /* defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) */
1339 #if defined(HAVE_LIBIAF) && !defined(BROKEN_LIBIAF)
1340 if (set_id(pw->pw_name) != 0) {
1343 #endif /* HAVE_LIBIAF && !BROKEN_LIBIAF */
1344 /* Permanently switch to the desired uid. */
1345 permanently_set_uid(pw);
1352 if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid)
1353 fatal("Failed to set uids to %u.", (u_int) pw->pw_uid);
1357 do_pwchange(Session *s)
1360 fprintf(stderr, "WARNING: Your password has expired.\n");
1361 if (s->ttyfd != -1) {
1363 "You must change your password now and login again!\n");
1364 #ifdef PASSWD_NEEDS_USERNAME
1365 execl(_PATH_PASSWD_PROG, "passwd", s->pw->pw_name,
1368 execl(_PATH_PASSWD_PROG, "passwd", (char *)NULL);
1373 "Password change required but no TTY available.\n");
1379 launch_login(struct passwd *pw, const char *hostname)
1381 /* Launch login(1). */
1383 execl(LOGIN_PROGRAM, "login", "-h", hostname,
1384 #ifdef xxxLOGIN_NEEDS_TERM
1385 (s->term ? s->term : "unknown"),
1386 #endif /* LOGIN_NEEDS_TERM */
1387 #ifdef LOGIN_NO_ENDOPT
1388 "-p", "-f", pw->pw_name, (char *)NULL);
1390 "-p", "-f", "--", pw->pw_name, (char *)NULL);
1393 /* Login couldn't be executed, die. */
1400 child_close_fds(void)
1404 if (packet_get_connection_in() == packet_get_connection_out())
1405 close(packet_get_connection_in());
1407 close(packet_get_connection_in());
1408 close(packet_get_connection_out());
1411 * Close all descriptors related to channels. They will still remain
1412 * open in the parent.
1414 /* XXX better use close-on-exec? -markus */
1415 channel_close_all();
1418 * Close any extra file descriptors. Note that there may still be
1419 * descriptors left by system functions. They will be closed later.
1424 * Close any extra open file descriptors so that we don't have them
1425 * hanging around in clients. Note that we want to do this after
1426 * initgroups, because at least on Solaris 2.3 it leaves file
1429 for (i = 3; i < 64; i++)
1434 * Performs common processing for the child, such as setting up the
1435 * environment, closing extra file descriptors, setting the user and group
1436 * ids, and executing the command or shell.
1439 do_child(Session *s, const char *command)
1441 extern char **environ;
1444 const char *shell, *shell0, *hostname = NULL;
1445 struct passwd *pw = s->pw;
1447 /* remove hostkey from the child's memory */
1448 destroy_sensitive_data();
1450 /* Force a password change */
1451 if (s->authctxt->force_pwchange) {
1452 do_setusercontext(pw);
1458 /* login(1) is only called if we execute the login shell */
1459 if (options.use_login && command != NULL)
1460 options.use_login = 0;
1463 cray_setup(pw->pw_uid, pw->pw_name, command);
1464 #endif /* _UNICOS */
1467 * Login(1) does this as well, and it needs uid 0 for the "-h"
1468 * switch, so we let login(1) to this for us.
1470 if (!options.use_login) {
1472 session_setup_sia(pw, s->ttyfd == -1 ? NULL : s->tty);
1473 if (!check_quietlogin(s, command))
1475 #else /* HAVE_OSF_SIA */
1476 /* When PAM is enabled we rely on it to do the nologin check */
1477 if (!options.use_pam)
1479 do_setusercontext(pw);
1481 * PAM session modules in do_setusercontext may have
1482 * generated messages, so if this in an interactive
1483 * login then display them too.
1485 if (!check_quietlogin(s, command))
1487 #endif /* HAVE_OSF_SIA */
1491 if (options.use_pam && !options.use_login && !is_pam_session_open()) {
1492 debug3("PAM session not opened, exiting");
1499 * Get the shell from the password data. An empty shell field is
1500 * legal, and means /bin/sh.
1502 shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
1505 * Make sure $SHELL points to the shell from the password file,
1506 * even if shell is overridden from login.conf
1508 env = do_setup_env(s, shell);
1510 #ifdef HAVE_LOGIN_CAP
1511 shell = login_getcapstr(lc, "shell", (char *)shell, (char *)shell);
1514 /* we have to stash the hostname before we close our socket. */
1515 if (options.use_login)
1516 hostname = get_remote_name_or_ip(utmp_len,
1519 * Close the connection descriptors; note that this is the child, and
1520 * the server will still have the socket open, and it is important
1521 * that we do not shutdown it. Note that the descriptors cannot be
1522 * closed before building the environment, as we call
1523 * get_remote_ipaddr there.
1528 * Must take new environment into use so that .ssh/rc,
1529 * /etc/ssh/sshrc and xauth are run in the proper environment.
1533 #if defined(KRB5) && defined(USE_AFS)
1535 * At this point, we check to see if AFS is active and if we have
1536 * a valid Kerberos 5 TGT. If so, it seems like a good idea to see
1537 * if we can (and need to) extend the ticket into an AFS token. If
1538 * we don't do this, we run into potential problems if the user's
1539 * home directory is in AFS and it's not world-readable.
1542 if (options.kerberos_get_afs_token && k_hasafs() &&
1543 (s->authctxt->krb5_ctx != NULL)) {
1546 debug("Getting AFS token");
1550 if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0)
1551 krb5_afslog(s->authctxt->krb5_ctx,
1552 s->authctxt->krb5_fwd_ccache, cell, NULL);
1554 krb5_afslog_home(s->authctxt->krb5_ctx,
1555 s->authctxt->krb5_fwd_ccache, NULL, NULL, pw->pw_dir);
1559 /* Change current directory to the user's home directory. */
1560 if (chdir(pw->pw_dir) < 0) {
1561 fprintf(stderr, "Could not chdir to home directory %s: %s\n",
1562 pw->pw_dir, strerror(errno));
1563 #ifdef HAVE_LOGIN_CAP
1564 if (login_getcapbool(lc, "requirehome", 0))
1569 if (!options.use_login)
1570 do_rc_files(s, shell);
1572 /* restore SIGPIPE for child */
1573 signal(SIGPIPE, SIG_DFL);
1575 if (options.use_login) {
1576 launch_login(pw, hostname);
1580 /* Get the last component of the shell name. */
1581 if ((shell0 = strrchr(shell, '/')) != NULL)
1587 * If we have no command, execute the shell. In this case, the shell
1588 * name to be passed in argv[0] is preceded by '-' to indicate that
1589 * this is a login shell.
1594 /* Start the shell. Set initial character to '-'. */
1597 if (strlcpy(argv0 + 1, shell0, sizeof(argv0) - 1)
1598 >= sizeof(argv0) - 1) {
1604 /* Execute the shell. */
1607 execve(shell, argv, env);
1609 /* Executing the shell failed. */
1614 * Execute the command using the user's shell. This uses the -c
1615 * option to execute the command.
1617 argv[0] = (char *) shell0;
1619 argv[2] = (char *) command;
1621 execve(shell, argv, env);
1630 static int did_init = 0;
1632 debug("session_new: init");
1633 for (i = 0; i < MAX_SESSIONS; i++) {
1634 sessions[i].used = 0;
1638 for (i = 0; i < MAX_SESSIONS; i++) {
1639 Session *s = &sessions[i];
1641 memset(s, 0, sizeof(*s));
1647 s->x11_chanids = NULL;
1648 debug("session_new: session %d", i);
1659 for (i = 0; i < MAX_SESSIONS; i++) {
1660 Session *s = &sessions[i];
1661 debug("dump: used %d session %d %p channel %d pid %ld",
1671 session_open(Authctxt *authctxt, int chanid)
1673 Session *s = session_new();
1674 debug("session_open: channel %d", chanid);
1676 error("no more sessions");
1679 s->authctxt = authctxt;
1680 s->pw = authctxt->pw;
1681 if (s->pw == NULL || !authctxt->valid)
1682 fatal("no user for session %d", s->self);
1683 debug("session_open: session %d: link with channel %d", s->self, chanid);
1689 session_by_tty(char *tty)
1692 for (i = 0; i < MAX_SESSIONS; i++) {
1693 Session *s = &sessions[i];
1694 if (s->used && s->ttyfd != -1 && strcmp(s->tty, tty) == 0) {
1695 debug("session_by_tty: session %d tty %s", i, tty);
1699 debug("session_by_tty: unknown tty %.100s", tty);
1705 session_by_channel(int id)
1708 for (i = 0; i < MAX_SESSIONS; i++) {
1709 Session *s = &sessions[i];
1710 if (s->used && s->chanid == id) {
1711 debug("session_by_channel: session %d channel %d", i, id);
1715 debug("session_by_channel: unknown channel %d", id);
1721 session_by_x11_channel(int id)
1725 for (i = 0; i < MAX_SESSIONS; i++) {
1726 Session *s = &sessions[i];
1728 if (s->x11_chanids == NULL || !s->used)
1730 for (j = 0; s->x11_chanids[j] != -1; j++) {
1731 if (s->x11_chanids[j] == id) {
1732 debug("session_by_x11_channel: session %d "
1733 "channel %d", s->self, id);
1738 debug("session_by_x11_channel: unknown channel %d", id);
1744 session_by_pid(pid_t pid)
1747 debug("session_by_pid: pid %ld", (long)pid);
1748 for (i = 0; i < MAX_SESSIONS; i++) {
1749 Session *s = &sessions[i];
1750 if (s->used && s->pid == pid)
1753 error("session_by_pid: unknown pid %ld", (long)pid);
1759 session_window_change_req(Session *s)
1761 s->col = packet_get_int();
1762 s->row = packet_get_int();
1763 s->xpixel = packet_get_int();
1764 s->ypixel = packet_get_int();
1766 pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1771 session_pty_req(Session *s)
1777 debug("Allocating a pty not permitted for this authentication.");
1780 if (s->ttyfd != -1) {
1781 packet_disconnect("Protocol error: you already have a pty.");
1785 s->term = packet_get_string(&len);
1788 s->col = packet_get_int();
1789 s->row = packet_get_int();
1791 s->row = packet_get_int();
1792 s->col = packet_get_int();
1794 s->xpixel = packet_get_int();
1795 s->ypixel = packet_get_int();
1797 if (strcmp(s->term, "") == 0) {
1802 /* Allocate a pty and open it. */
1803 debug("Allocating pty.");
1804 if (!PRIVSEP(pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty)))) {
1810 error("session_pty_req: session %d alloc failed", s->self);
1813 debug("session_pty_req: session %d alloc %s", s->self, s->tty);
1815 /* for SSH1 the tty modes length is not given */
1817 n_bytes = packet_remaining();
1818 tty_parse_modes(s->ttyfd, &n_bytes);
1821 pty_setowner(s->pw, s->tty);
1823 /* Set window size from the packet. */
1824 pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1827 session_proctitle(s);
1832 session_subsystem_req(Session *s)
1837 char *cmd, *subsys = packet_get_string(&len);
1841 logit("subsystem request for %.100s", subsys);
1843 for (i = 0; i < options.num_subsystems; i++) {
1844 if (strcmp(subsys, options.subsystem_name[i]) == 0) {
1845 cmd = options.subsystem_command[i];
1846 if (stat(cmd, &st) < 0) {
1847 error("subsystem: cannot stat %s: %s", cmd,
1851 debug("subsystem: exec() %s", cmd);
1852 s->is_subsystem = 1;
1860 logit("subsystem request for %.100s failed, subsystem not found",
1868 session_x11_req(Session *s)
1872 if (s->auth_proto != NULL || s->auth_data != NULL) {
1873 error("session_x11_req: session %d: "
1874 "x11 forwarding already active", s->self);
1877 s->single_connection = packet_get_char();
1878 s->auth_proto = packet_get_string(NULL);
1879 s->auth_data = packet_get_string(NULL);
1880 s->screen = packet_get_int();
1883 success = session_setup_x11fwd(s);
1885 xfree(s->auth_proto);
1886 xfree(s->auth_data);
1887 s->auth_proto = NULL;
1888 s->auth_data = NULL;
1894 session_shell_req(Session *s)
1902 session_exec_req(Session *s)
1905 char *command = packet_get_string(&len);
1907 do_exec(s, command);
1913 session_break_req(Session *s)
1916 packet_get_int(); /* ignored */
1919 if (s->ttyfd == -1 ||
1920 tcsendbreak(s->ttyfd, 0) < 0)
1926 session_env_req(Session *s)
1929 u_int name_len, val_len, i;
1931 name = packet_get_string(&name_len);
1932 val = packet_get_string(&val_len);
1935 /* Don't set too many environment variables */
1936 if (s->num_env > 128) {
1937 debug2("Ignoring env request %s: too many env vars", name);
1941 for (i = 0; i < options.num_accept_env; i++) {
1942 if (match_pattern(name, options.accept_env[i])) {
1943 debug2("Setting env %d: %s=%s", s->num_env, name, val);
1944 s->env = xrealloc(s->env, sizeof(*s->env) *
1946 s->env[s->num_env].name = name;
1947 s->env[s->num_env].val = val;
1952 debug2("Ignoring env request %s: disallowed name", name);
1961 session_auth_agent_req(Session *s)
1963 static int called = 0;
1965 if (no_agent_forwarding_flag) {
1966 debug("session_auth_agent_req: no_agent_forwarding_flag");
1973 return auth_input_request_forwarding(s->pw);
1978 session_input_channel_req(Channel *c, const char *rtype)
1983 if ((s = session_by_channel(c->self)) == NULL) {
1984 logit("session_input_channel_req: no session %d req %.100s",
1988 debug("session_input_channel_req: session %d req %s", s->self, rtype);
1991 * a session is in LARVAL state until a shell, a command
1992 * or a subsystem is executed
1994 if (c->type == SSH_CHANNEL_LARVAL) {
1995 if (strcmp(rtype, "shell") == 0) {
1996 success = session_shell_req(s);
1997 } else if (strcmp(rtype, "exec") == 0) {
1998 success = session_exec_req(s);
1999 } else if (strcmp(rtype, "pty-req") == 0) {
2000 success = session_pty_req(s);
2001 } else if (strcmp(rtype, "x11-req") == 0) {
2002 success = session_x11_req(s);
2003 } else if (strcmp(rtype, "auth-agent-req@openssh.com") == 0) {
2004 success = session_auth_agent_req(s);
2005 } else if (strcmp(rtype, "subsystem") == 0) {
2006 success = session_subsystem_req(s);
2007 } else if (strcmp(rtype, "env") == 0) {
2008 success = session_env_req(s);
2011 if (strcmp(rtype, "window-change") == 0) {
2012 success = session_window_change_req(s);
2013 } else if (strcmp(rtype, "break") == 0) {
2014 success = session_break_req(s);
2021 session_set_fds(Session *s, int fdin, int fdout, int fderr)
2024 fatal("session_set_fds: called for proto != 2.0");
2026 * now that have a child and a pipe to the child,
2027 * we can activate our channel and register the fd's
2029 if (s->chanid == -1)
2030 fatal("no channel for session %d", s->self);
2031 channel_set_fds(s->chanid,
2033 fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ,
2035 CHAN_SES_WINDOW_DEFAULT);
2039 * Function to perform pty cleanup. Also called if we get aborted abnormally
2040 * (e.g., due to a dropped connection).
2043 session_pty_cleanup2(Session *s)
2046 error("session_pty_cleanup: no session");
2052 debug("session_pty_cleanup: session %d release %s", s->self, s->tty);
2054 /* Record that the user has logged out. */
2056 record_logout(s->pid, s->tty, s->pw->pw_name);
2058 /* Release the pseudo-tty. */
2060 pty_release(s->tty);
2063 * Close the server side of the socket pairs. We must do this after
2064 * the pty cleanup, so that another process doesn't get this pty
2065 * while we're still cleaning up.
2067 if (close(s->ptymaster) < 0)
2068 error("close(s->ptymaster/%d): %s", s->ptymaster, strerror(errno));
2070 /* unlink pty from session */
2075 session_pty_cleanup(Session *s)
2077 PRIVSEP(session_pty_cleanup2(s));
2083 #define SSH_SIG(x) if (sig == SIG ## x) return #x
2098 return "SIG@openssh.com";
2102 session_close_x11(int id)
2106 if ((c = channel_by_id(id)) == NULL) {
2107 debug("session_close_x11: x11 channel %d missing", id);
2109 /* Detach X11 listener */
2110 debug("session_close_x11: detach x11 channel %d", id);
2111 channel_cancel_cleanup(id);
2112 if (c->ostate != CHAN_OUTPUT_CLOSED)
2118 session_close_single_x11(int id, void *arg)
2123 debug3("session_close_single_x11: channel %d", id);
2124 channel_cancel_cleanup(id);
2125 if ((s = session_by_x11_channel(id)) == NULL)
2126 fatal("session_close_single_x11: no x11 channel %d", id);
2127 for (i = 0; s->x11_chanids[i] != -1; i++) {
2128 debug("session_close_single_x11: session %d: "
2129 "closing channel %d", s->self, s->x11_chanids[i]);
2131 * The channel "id" is already closing, but make sure we
2132 * close all of its siblings.
2134 if (s->x11_chanids[i] != id)
2135 session_close_x11(s->x11_chanids[i]);
2137 xfree(s->x11_chanids);
2138 s->x11_chanids = NULL;
2143 if (s->auth_proto) {
2144 xfree(s->auth_proto);
2145 s->auth_proto = NULL;
2148 xfree(s->auth_data);
2149 s->auth_data = NULL;
2151 if (s->auth_display) {
2152 xfree(s->auth_display);
2153 s->auth_display = NULL;
2158 session_exit_message(Session *s, int status)
2162 if ((c = channel_lookup(s->chanid)) == NULL)
2163 fatal("session_exit_message: session %d: no channel %d",
2164 s->self, s->chanid);
2165 debug("session_exit_message: session %d channel %d pid %ld",
2166 s->self, s->chanid, (long)s->pid);
2168 if (WIFEXITED(status)) {
2169 channel_request_start(s->chanid, "exit-status", 0);
2170 packet_put_int(WEXITSTATUS(status));
2172 } else if (WIFSIGNALED(status)) {
2173 channel_request_start(s->chanid, "exit-signal", 0);
2174 packet_put_cstring(sig2name(WTERMSIG(status)));
2176 packet_put_char(WCOREDUMP(status));
2177 #else /* WCOREDUMP */
2179 #endif /* WCOREDUMP */
2180 packet_put_cstring("");
2181 packet_put_cstring("");
2184 /* Some weird exit cause. Just exit. */
2185 packet_disconnect("wait returned status %04x.", status);
2188 /* disconnect channel */
2189 debug("session_exit_message: release channel %d", s->chanid);
2192 * Adjust cleanup callback attachment to send close messages when
2193 * the channel gets EOF. The session will be then be closed
2194 * by session_close_by_channel when the childs close their fds.
2196 channel_register_cleanup(c->self, session_close_by_channel, 1);
2199 * emulate a write failure with 'chan_write_failed', nobody will be
2200 * interested in data we write.
2201 * Note that we must not call 'chan_read_failed', since there could
2202 * be some more data waiting in the pipe.
2204 if (c->ostate != CHAN_OUTPUT_CLOSED)
2205 chan_write_failed(c);
2209 session_close(Session *s)
2213 debug("session_close: session %d pid %ld", s->self, (long)s->pid);
2215 session_pty_cleanup(s);
2221 xfree(s->x11_chanids);
2222 if (s->auth_display)
2223 xfree(s->auth_display);
2225 xfree(s->auth_data);
2227 xfree(s->auth_proto);
2229 for (i = 0; i < s->num_env; i++) {
2230 xfree(s->env[i].name);
2231 xfree(s->env[i].val);
2235 session_proctitle(s);
2239 session_close_by_pid(pid_t pid, int status)
2241 Session *s = session_by_pid(pid);
2243 debug("session_close_by_pid: no session for pid %ld",
2247 if (s->chanid != -1)
2248 session_exit_message(s, status);
2250 session_pty_cleanup(s);
2255 * this is called when a channel dies before
2256 * the session 'child' itself dies
2259 session_close_by_channel(int id, void *arg)
2261 Session *s = session_by_channel(id);
2265 debug("session_close_by_channel: no session for id %d", id);
2268 debug("session_close_by_channel: channel %d child %ld",
2271 debug("session_close_by_channel: channel %d: has child", id);
2273 * delay detach of session, but release pty, since
2274 * the fd's to the child are already closed
2277 session_pty_cleanup(s);
2280 /* detach by removing callback */
2281 channel_cancel_cleanup(s->chanid);
2283 /* Close any X11 listeners associated with this session */
2284 if (s->x11_chanids != NULL) {
2285 for (i = 0; s->x11_chanids[i] != -1; i++) {
2286 session_close_x11(s->x11_chanids[i]);
2287 s->x11_chanids[i] = -1;
2296 session_destroy_all(void (*closefunc)(Session *))
2299 for (i = 0; i < MAX_SESSIONS; i++) {
2300 Session *s = &sessions[i];
2302 if (closefunc != NULL)
2311 session_tty_list(void)
2313 static char buf[1024];
2318 for (i = 0; i < MAX_SESSIONS; i++) {
2319 Session *s = &sessions[i];
2320 if (s->used && s->ttyfd != -1) {
2322 if (strncmp(s->tty, "/dev/", 5) != 0) {
2323 cp = strrchr(s->tty, '/');
2324 cp = (cp == NULL) ? s->tty : cp + 1;
2329 strlcat(buf, ",", sizeof buf);
2330 strlcat(buf, cp, sizeof buf);
2334 strlcpy(buf, "notty", sizeof buf);
2339 session_proctitle(Session *s)
2342 error("no user for session %d", s->self);
2344 setproctitle("%s@%s", s->pw->pw_name, session_tty_list());
2348 session_setup_x11fwd(Session *s)
2351 char display[512], auth_display[512];
2352 char hostname[MAXHOSTNAMELEN];
2355 if (no_x11_forwarding_flag) {
2356 packet_send_debug("X11 forwarding disabled in user configuration file.");
2359 if (!options.x11_forwarding) {
2360 debug("X11 forwarding disabled in server configuration file.");
2363 if (!options.xauth_location ||
2364 (stat(options.xauth_location, &st) == -1)) {
2365 packet_send_debug("No xauth program; cannot forward with spoofing.");
2368 if (options.use_login) {
2369 packet_send_debug("X11 forwarding disabled; "
2370 "not compatible with UseLogin=yes.");
2373 if (s->display != NULL) {
2374 debug("X11 display already set.");
2377 if (x11_create_display_inet(options.x11_display_offset,
2378 options.x11_use_localhost, s->single_connection,
2379 &s->display_number, &s->x11_chanids) == -1) {
2380 debug("x11_create_display_inet failed.");
2383 for (i = 0; s->x11_chanids[i] != -1; i++) {
2384 channel_register_cleanup(s->x11_chanids[i],
2385 session_close_single_x11, 0);
2388 /* Set up a suitable value for the DISPLAY variable. */
2389 if (gethostname(hostname, sizeof(hostname)) < 0)
2390 fatal("gethostname: %.100s", strerror(errno));
2392 * auth_display must be used as the displayname when the
2393 * authorization entry is added with xauth(1). This will be
2394 * different than the DISPLAY string for localhost displays.
2396 if (options.x11_use_localhost) {
2397 snprintf(display, sizeof display, "localhost:%u.%u",
2398 s->display_number, s->screen);
2399 snprintf(auth_display, sizeof auth_display, "unix:%u.%u",
2400 s->display_number, s->screen);
2401 s->display = xstrdup(display);
2402 s->auth_display = xstrdup(auth_display);
2404 #ifdef IPADDR_IN_DISPLAY
2406 struct in_addr my_addr;
2408 he = gethostbyname(hostname);
2410 error("Can't get IP address for X11 DISPLAY.");
2411 packet_send_debug("Can't get IP address for X11 DISPLAY.");
2414 memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr));
2415 snprintf(display, sizeof display, "%.50s:%u.%u", inet_ntoa(my_addr),
2416 s->display_number, s->screen);
2418 snprintf(display, sizeof display, "%.400s:%u.%u", hostname,
2419 s->display_number, s->screen);
2421 s->display = xstrdup(display);
2422 s->auth_display = xstrdup(display);
2429 do_authenticated2(Authctxt *authctxt)
2431 server_loop2(authctxt);
2435 do_cleanup(Authctxt *authctxt)
2437 static int called = 0;
2439 debug("do_cleanup");
2441 /* no cleanup if we're in the child for login shell */
2445 /* avoid double cleanup */
2450 if (authctxt == NULL)
2453 if (options.kerberos_ticket_cleanup &&
2455 krb5_cleanup_proc(authctxt);
2459 if (compat20 && options.gss_cleanup_creds)
2460 ssh_gssapi_cleanup_creds();
2464 if (options.use_pam) {
2466 sshpam_thread_cleanup();
2470 /* remove agent socket */
2471 auth_sock_cleanup_proc(authctxt->pw);
2474 * Cleanup ptys/utmp only if privsep is disabled,
2475 * or if running in monitor.
2477 if (!use_privsep || mm_is_monitor())
2478 session_destroy_all(session_pty_cleanup2);