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 1.143 2002/06/30 21:54:16 deraadt Exp $");
51 #include "auth-options.h"
52 #include "pathnames.h"
56 #include "serverloop.h"
59 #include "monitor_wrap.h"
63 #include <sys/cygwin.h>
64 #define is_winnt (GetVersion() < 0x80000000)
69 Session *session_new(void);
70 void session_set_fds(Session *, int, int, int);
71 void session_pty_cleanup(void *);
72 void session_proctitle(Session *);
73 int session_setup_x11fwd(Session *);
74 void do_exec_pty(Session *, const char *);
75 void do_exec_no_pty(Session *, const char *);
76 void do_exec(Session *, const char *);
77 void do_login(Session *, const char *);
78 #ifdef LOGIN_NEEDS_UTMPX
79 static void do_pre_login(Session *s);
81 void do_child(Session *, const char *);
83 int check_quietlogin(Session *, const char *);
85 static void do_authenticated1(Authctxt *);
86 static void do_authenticated2(Authctxt *);
88 static int session_pty_req(Session *);
91 extern ServerOptions options;
92 extern char *__progname;
93 extern int log_stderr;
94 extern int debug_flag;
95 extern u_int utmp_len;
96 extern int startup_pipe;
97 extern void destroy_sensitive_data(void);
99 /* original command from peer. */
100 const char *original_command = NULL;
103 #define MAX_SESSIONS 10
104 Session sessions[MAX_SESSIONS];
106 #ifdef WITH_AIXAUTHENTICATE
108 #endif /* WITH_AIXAUTHENTICATE */
110 #ifdef HAVE_LOGIN_CAP
114 /* Name and directory of socket for authentication agent forwarding. */
115 static char *auth_sock_name = NULL;
116 static char *auth_sock_dir = NULL;
118 /* removes the agent forwarding socket */
121 auth_sock_cleanup_proc(void *_pw)
123 struct passwd *pw = _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-XXXXXXXX", 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 /* delete agent socket on fatal() */
169 fatal_add_cleanup(auth_sock_cleanup_proc, pw);
171 /* Create the socket. */
172 sock = socket(AF_UNIX, SOCK_STREAM, 0);
174 packet_disconnect("socket: %.100s", strerror(errno));
176 /* Bind it to the name. */
177 memset(&sunaddr, 0, sizeof(sunaddr));
178 sunaddr.sun_family = AF_UNIX;
179 strlcpy(sunaddr.sun_path, auth_sock_name, sizeof(sunaddr.sun_path));
181 if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0)
182 packet_disconnect("bind: %.100s", strerror(errno));
184 /* Restore the privileged uid. */
187 /* Start listening on the socket. */
188 if (listen(sock, 5) < 0)
189 packet_disconnect("listen: %.100s", strerror(errno));
191 /* Allocate a channel for the authentication agent socket. */
192 nc = channel_new("auth socket",
193 SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1,
194 CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
195 0, xstrdup("auth socket"), 1);
196 strlcpy(nc->path, auth_sock_name, sizeof(nc->path));
202 do_authenticated(Authctxt *authctxt)
205 * Cancel the alarm we set to limit the time taken for
209 if (startup_pipe != -1) {
213 #ifdef WITH_AIXAUTHENTICATE
214 /* We don't have a pty yet, so just label the line as "ssh" */
215 if (loginsuccess(authctxt->user,
216 get_canonical_hostname(options.verify_reverse_mapping),
217 "ssh", &aixloginmsg) < 0)
219 #endif /* WITH_AIXAUTHENTICATE */
221 /* setup the channel layer */
222 if (!no_port_forwarding_flag && options.allow_tcp_forwarding)
223 channel_permit_all_opens();
226 do_authenticated2(authctxt);
228 do_authenticated1(authctxt);
230 /* remove agent socket */
231 if (auth_sock_name != NULL)
232 auth_sock_cleanup_proc(authctxt->pw);
234 if (options.kerberos_ticket_cleanup)
235 krb4_cleanup_proc(authctxt);
238 if (options.kerberos_ticket_cleanup)
239 krb5_cleanup_proc(authctxt);
244 * Prepares for an interactive session. This is called after the user has
245 * been successfully authenticated. During this message exchange, pseudo
246 * terminals are allocated, X11, TCP/IP, and authentication agent forwardings
247 * are requested, etc.
250 do_authenticated1(Authctxt *authctxt)
254 int success, type, screen_flag;
255 int enable_compression_after_reply = 0;
256 u_int proto_len, data_len, dlen, compression_level = 0;
259 s->authctxt = authctxt;
260 s->pw = authctxt->pw;
263 * We stay in this loop until the client requests to execute a shell
269 /* Get a packet from the client. */
270 type = packet_read();
272 /* Process the packet. */
274 case SSH_CMSG_REQUEST_COMPRESSION:
275 compression_level = packet_get_int();
277 if (compression_level < 1 || compression_level > 9) {
278 packet_send_debug("Received illegal compression level %d.",
282 if (!options.compression) {
283 debug2("compression disabled");
286 /* Enable compression after we have responded with SUCCESS. */
287 enable_compression_after_reply = 1;
291 case SSH_CMSG_REQUEST_PTY:
292 success = session_pty_req(s);
295 case SSH_CMSG_X11_REQUEST_FORWARDING:
296 s->auth_proto = packet_get_string(&proto_len);
297 s->auth_data = packet_get_string(&data_len);
299 screen_flag = packet_get_protocol_flags() &
300 SSH_PROTOFLAG_SCREEN_NUMBER;
301 debug2("SSH_PROTOFLAG_SCREEN_NUMBER: %d", screen_flag);
303 if (packet_remaining() == 4) {
305 debug2("Buggy client: "
306 "X11 screen flag missing");
307 s->screen = packet_get_int();
312 success = session_setup_x11fwd(s);
314 xfree(s->auth_proto);
316 s->auth_proto = NULL;
321 case SSH_CMSG_AGENT_REQUEST_FORWARDING:
322 if (no_agent_forwarding_flag || compat13) {
323 debug("Authentication agent forwarding not permitted for this authentication.");
326 debug("Received authentication agent forwarding request.");
327 success = auth_input_request_forwarding(s->pw);
330 case SSH_CMSG_PORT_FORWARD_REQUEST:
331 if (no_port_forwarding_flag) {
332 debug("Port forwarding not permitted for this authentication.");
335 if (!options.allow_tcp_forwarding) {
336 debug("Port forwarding not permitted.");
339 debug("Received TCP/IP port forwarding request.");
340 channel_input_port_forward_request(s->pw->pw_uid == 0, options.gateway_ports);
344 case SSH_CMSG_MAX_PACKET_SIZE:
345 if (packet_set_maxsize(packet_get_int()) > 0)
349 #if defined(AFS) || defined(KRB5)
350 case SSH_CMSG_HAVE_KERBEROS_TGT:
351 if (!options.kerberos_tgt_passing) {
352 verbose("Kerberos TGT passing disabled.");
354 char *kdata = packet_get_string(&dlen);
357 /* XXX - 0x41, see creds_to_radix version */
358 if (kdata[0] != 0x41) {
364 if (auth_krb5_tgt(s->authctxt, &tgt))
367 verbose("Kerberos v5 TGT refused for %.100s", s->authctxt->user);
371 if (auth_krb4_tgt(s->authctxt, kdata))
374 verbose("Kerberos v4 TGT refused for %.100s", s->authctxt->user);
380 #endif /* AFS || KRB5 */
383 case SSH_CMSG_HAVE_AFS_TOKEN:
384 if (!options.afs_token_passing || !k_hasafs()) {
385 verbose("AFS token passing disabled.");
387 /* Accept AFS token. */
388 char *token = packet_get_string(&dlen);
391 if (auth_afs_token(s->authctxt, token))
394 verbose("AFS token refused for %.100s",
401 case SSH_CMSG_EXEC_SHELL:
402 case SSH_CMSG_EXEC_CMD:
403 if (type == SSH_CMSG_EXEC_CMD) {
404 command = packet_get_string(&dlen);
405 debug("Exec command '%.500s'", command);
417 * Any unknown messages in this phase are ignored,
418 * and a failure message is returned.
420 log("Unknown packet type received after authentication: %d", type);
422 packet_start(success ? SSH_SMSG_SUCCESS : SSH_SMSG_FAILURE);
426 /* Enable compression now that we have replied if appropriate. */
427 if (enable_compression_after_reply) {
428 enable_compression_after_reply = 0;
429 packet_start_compression(compression_level);
435 * This is called to fork and execute a command when we have no tty. This
436 * will call do_child from the child, and server_loop from the parent after
437 * setting up file descriptors and such.
440 do_exec_no_pty(Session *s, const char *command)
445 int pin[2], pout[2], perr[2];
446 /* Allocate pipes for communicating with the program. */
447 if (pipe(pin) < 0 || pipe(pout) < 0 || pipe(perr) < 0)
448 packet_disconnect("Could not create pipes: %.100s",
450 #else /* USE_PIPES */
451 int inout[2], err[2];
452 /* Uses socket pairs to communicate with the program. */
453 if (socketpair(AF_UNIX, SOCK_STREAM, 0, inout) < 0 ||
454 socketpair(AF_UNIX, SOCK_STREAM, 0, err) < 0)
455 packet_disconnect("Could not create socket pairs: %.100s",
457 #endif /* USE_PIPES */
459 fatal("do_exec_no_pty: no session");
461 session_proctitle(s);
464 do_pam_session(s->pw->pw_name, NULL);
466 if (is_pam_password_change_required())
467 packet_disconnect("Password change required but no "
471 /* Fork the child. */
472 if ((pid = fork()) == 0) {
473 /* Child. Reinitialize the log since the pid has changed. */
474 log_init(__progname, options.log_level, options.log_facility, log_stderr);
477 * Create a new session and process group since the 4.4BSD
478 * setlogin() affects the entire process group.
481 error("setsid failed: %.100s", strerror(errno));
485 * Redirect stdin. We close the parent side of the socket
486 * pair, and make the child side the standard input.
489 if (dup2(pin[0], 0) < 0)
490 perror("dup2 stdin");
493 /* Redirect stdout. */
495 if (dup2(pout[1], 1) < 0)
496 perror("dup2 stdout");
499 /* Redirect stderr. */
501 if (dup2(perr[1], 2) < 0)
502 perror("dup2 stderr");
504 #else /* USE_PIPES */
506 * Redirect stdin, stdout, and stderr. Stdin and stdout will
507 * use the same socket, as some programs (particularly rdist)
508 * seem to depend on it.
512 if (dup2(inout[0], 0) < 0) /* stdin */
513 perror("dup2 stdin");
514 if (dup2(inout[0], 1) < 0) /* stdout. Note: same socket as stdin. */
515 perror("dup2 stdout");
516 if (dup2(err[0], 2) < 0) /* stderr */
517 perror("dup2 stderr");
518 #endif /* USE_PIPES */
520 /* Do processing for the child (exec command etc). */
521 do_child(s, command);
526 cygwin_set_impersonation_token(INVALID_HANDLE_VALUE);
529 packet_disconnect("fork failed: %.100s", strerror(errno));
531 /* Set interactive/non-interactive mode. */
532 packet_set_interactive(s->display != NULL);
534 /* We are the parent. Close the child sides of the pipes. */
540 session_set_fds(s, pin[1], pout[0], s->is_subsystem ? -1 : perr[0]);
542 /* Enter the interactive session. */
543 server_loop(pid, pin[1], pout[0], perr[0]);
544 /* server_loop has closed pin[1], pout[0], and perr[0]. */
546 #else /* USE_PIPES */
547 /* We are the parent. Close the child sides of the socket pairs. */
552 * Enter the interactive session. Note: server_loop must be able to
553 * handle the case that fdin and fdout are the same.
556 session_set_fds(s, inout[1], inout[1], s->is_subsystem ? -1 : err[1]);
558 server_loop(pid, inout[1], inout[1], err[1]);
559 /* server_loop has closed inout[1] and err[1]. */
561 #endif /* USE_PIPES */
565 * This is called to fork and execute a command when we have a tty. This
566 * will call do_child from the child, and server_loop from the parent after
567 * setting up file descriptors, controlling tty, updating wtmp, utmp,
568 * lastlog, and other such operations.
571 do_exec_pty(Session *s, const char *command)
573 int fdout, ptyfd, ttyfd, ptymaster;
577 fatal("do_exec_pty: no session");
582 do_pam_session(s->pw->pw_name, s->tty);
586 /* Fork the child. */
587 if ((pid = fork()) == 0) {
589 /* Child. Reinitialize the log because the pid has changed. */
590 log_init(__progname, options.log_level, options.log_facility, log_stderr);
591 /* Close the master side of the pseudo tty. */
594 /* Make the pseudo tty our controlling tty. */
595 pty_make_controlling_tty(&ttyfd, s->tty);
597 /* Redirect stdin/stdout/stderr from the pseudo tty. */
598 if (dup2(ttyfd, 0) < 0)
599 error("dup2 stdin: %s", strerror(errno));
600 if (dup2(ttyfd, 1) < 0)
601 error("dup2 stdout: %s", strerror(errno));
602 if (dup2(ttyfd, 2) < 0)
603 error("dup2 stderr: %s", strerror(errno));
605 /* Close the extra descriptor for the pseudo tty. */
608 /* record login, etc. similar to login(1) */
610 if (!(options.use_login && command == NULL))
611 do_login(s, command);
612 # ifdef LOGIN_NEEDS_UTMPX
618 /* Do common processing for the child, such as execing the command. */
619 do_child(s, command);
624 cygwin_set_impersonation_token(INVALID_HANDLE_VALUE);
627 packet_disconnect("fork failed: %.100s", strerror(errno));
630 /* Parent. Close the slave side of the pseudo tty. */
634 * Create another descriptor of the pty master side for use as the
635 * standard input. We could use the original descriptor, but this
636 * simplifies code in server_loop. The descriptor is bidirectional.
640 packet_disconnect("dup #1 failed: %.100s", strerror(errno));
642 /* we keep a reference to the pty master */
643 ptymaster = dup(ptyfd);
645 packet_disconnect("dup #2 failed: %.100s", strerror(errno));
646 s->ptymaster = ptymaster;
648 /* Enter interactive session. */
649 packet_set_interactive(1);
651 session_set_fds(s, ptyfd, fdout, -1);
653 server_loop(pid, ptyfd, fdout, -1);
654 /* server_loop _has_ closed ptyfd and fdout. */
658 #ifdef LOGIN_NEEDS_UTMPX
660 do_pre_login(Session *s)
663 struct sockaddr_storage from;
664 pid_t pid = getpid();
667 * Get IP address of client. If the connection is not a socket, let
668 * the address be 0.0.0.0.
670 memset(&from, 0, sizeof(from));
671 if (packet_connection_is_on_socket()) {
672 fromlen = sizeof(from);
673 if (getpeername(packet_get_connection_in(),
674 (struct sockaddr *) & from, &fromlen) < 0) {
675 debug("getpeername: %.100s", strerror(errno));
680 record_utmp_only(pid, s->tty, s->pw->pw_name,
681 get_remote_name_or_ip(utmp_len, options.verify_reverse_mapping),
682 (struct sockaddr *)&from);
687 * This is called to fork and execute a command. If another command is
688 * to be forced, execute that instead.
691 do_exec(Session *s, const char *command)
693 if (forced_command) {
694 original_command = command;
695 command = forced_command;
696 debug("Forced command '%.900s'", command);
700 do_exec_pty(s, command);
702 do_exec_no_pty(s, command);
704 original_command = NULL;
708 /* administrative, login(1)-like work */
710 do_login(Session *s, const char *command)
714 struct sockaddr_storage from;
715 struct passwd * pw = s->pw;
716 pid_t pid = getpid();
719 * Get IP address of client. If the connection is not a socket, let
720 * the address be 0.0.0.0.
722 memset(&from, 0, sizeof(from));
723 if (packet_connection_is_on_socket()) {
724 fromlen = sizeof(from);
725 if (getpeername(packet_get_connection_in(),
726 (struct sockaddr *) & from, &fromlen) < 0) {
727 debug("getpeername: %.100s", strerror(errno));
732 /* Record that there was a login on that tty from the remote host. */
734 record_login(pid, s->tty, pw->pw_name, pw->pw_uid,
735 get_remote_name_or_ip(utmp_len,
736 options.verify_reverse_mapping),
737 (struct sockaddr *)&from);
741 * If password change is needed, do it now.
742 * This needs to occur before the ~/.hushlogin check.
744 if (is_pam_password_change_required()) {
745 print_pam_messages();
750 if (check_quietlogin(s, command))
754 if (!is_pam_password_change_required())
755 print_pam_messages();
757 #ifdef WITH_AIXAUTHENTICATE
758 if (aixloginmsg && *aixloginmsg)
759 printf("%s\n", aixloginmsg);
760 #endif /* WITH_AIXAUTHENTICATE */
762 if (options.print_lastlog && s->last_login_time != 0) {
763 time_string = ctime(&s->last_login_time);
764 if (strchr(time_string, '\n'))
765 *strchr(time_string, '\n') = 0;
766 if (strcmp(s->hostname, "") == 0)
767 printf("Last login: %s\r\n", time_string);
769 printf("Last login: %s from %s\r\n", time_string,
777 * Display the message of the day.
785 if (options.print_motd) {
786 #ifdef HAVE_LOGIN_CAP
787 f = fopen(login_getcapstr(lc, "welcome", "/etc/motd",
790 f = fopen("/etc/motd", "r");
793 while (fgets(buf, sizeof(buf), f))
802 * Check for quiet login, either .hushlogin or command given.
805 check_quietlogin(Session *s, const char *command)
808 struct passwd *pw = s->pw;
811 /* Return 1 if .hushlogin exists or a command given. */
814 snprintf(buf, sizeof(buf), "%.200s/.hushlogin", pw->pw_dir);
815 #ifdef HAVE_LOGIN_CAP
816 if (login_getcapbool(lc, "hushlogin", 0) || stat(buf, &st) >= 0)
819 if (stat(buf, &st) >= 0)
826 * Sets the value of the given variable in the environment. If the variable
827 * already exists, its value is overriden.
830 child_set_env(char ***envp, u_int *envsizep, const char *name,
837 * Find the slot where the value should be stored. If the variable
838 * already exists, we reuse the slot; otherwise we append a new slot
839 * at the end of the array, expanding if necessary.
842 namelen = strlen(name);
843 for (i = 0; env[i]; i++)
844 if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=')
847 /* Reuse the slot. */
850 /* New variable. Expand if necessary. */
851 if (i >= (*envsizep) - 1) {
852 if (*envsizep >= 1000)
853 fatal("child_set_env: too many env vars,"
854 " skipping: %.100s", name);
856 env = (*envp) = xrealloc(env, (*envsizep) * sizeof(char *));
858 /* Need to set the NULL pointer at end of array beyond the new slot. */
862 /* Allocate space and format the variable in the appropriate slot. */
863 env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1);
864 snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value);
868 * Reads environment variables from the given file and adds/overrides them
869 * into the environment. If the file does not exist, this does nothing.
870 * Otherwise, it must consist of empty lines, comments (line starts with '#')
871 * and assignments of the form name=value. No other forms are allowed.
874 read_environment_file(char ***env, u_int *envsize,
875 const char *filename)
882 f = fopen(filename, "r");
886 while (fgets(buf, sizeof(buf), f)) {
888 fatal("Too many lines in environment file %s", filename);
889 for (cp = buf; *cp == ' ' || *cp == '\t'; cp++)
891 if (!*cp || *cp == '#' || *cp == '\n')
893 if (strchr(cp, '\n'))
894 *strchr(cp, '\n') = '\0';
895 value = strchr(cp, '=');
897 fprintf(stderr, "Bad line %u in %.100s\n", lineno,
902 * Replace the equals sign by nul, and advance value to
907 child_set_env(env, envsize, cp, value);
912 void copy_environment(char **source, char ***env, u_int *envsize)
914 char *var_name, *var_val;
920 for(i = 0; source[i] != NULL; i++) {
921 var_name = xstrdup(source[i]);
922 if ((var_val = strstr(var_name, "=")) == NULL) {
928 debug3("Copy environment: %s=%s", var_name, var_val);
929 child_set_env(env, envsize, var_name, var_val);
936 do_setup_env(Session *s, const char *shell)
941 struct passwd *pw = s->pw;
943 /* Initialize the environment. */
945 env = xmalloc(envsize * sizeof(char *));
950 * The Windows environment contains some setting which are
951 * important for a running system. They must not be dropped.
953 copy_environment(environ, &env, &envsize);
956 if (!options.use_login) {
957 /* Set basic environment. */
958 child_set_env(&env, &envsize, "USER", pw->pw_name);
959 child_set_env(&env, &envsize, "LOGNAME", pw->pw_name);
960 child_set_env(&env, &envsize, "HOME", pw->pw_dir);
961 #ifdef HAVE_LOGIN_CAP
962 (void) setusercontext(lc, pw, pw->pw_uid, LOGIN_SETPATH);
963 child_set_env(&env, &envsize, "PATH", getenv("PATH"));
964 #else /* HAVE_LOGIN_CAP */
967 * There's no standard path on Windows. The path contains
968 * important components pointing to the system directories,
969 * needed for loading shared libraries. So the path better
970 * remains intact here.
972 # ifdef SUPERUSER_PATH
973 child_set_env(&env, &envsize, "PATH",
974 s->pw->pw_uid == 0 ? SUPERUSER_PATH : _PATH_STDPATH);
976 child_set_env(&env, &envsize, "PATH", _PATH_STDPATH);
977 # endif /* SUPERUSER_PATH */
978 # endif /* HAVE_CYGWIN */
979 #endif /* HAVE_LOGIN_CAP */
981 snprintf(buf, sizeof buf, "%.200s/%.50s",
982 _PATH_MAILDIR, pw->pw_name);
983 child_set_env(&env, &envsize, "MAIL", buf);
985 /* Normal systems set SHELL by default. */
986 child_set_env(&env, &envsize, "SHELL", shell);
989 child_set_env(&env, &envsize, "TZ", getenv("TZ"));
991 /* Set custom environment options from RSA authentication. */
992 if (!options.use_login) {
993 while (custom_environment) {
994 struct envstring *ce = custom_environment;
997 for (i = 0; str[i] != '=' && str[i]; i++)
1001 child_set_env(&env, &envsize, str, str + i + 1);
1003 custom_environment = ce->next;
1009 snprintf(buf, sizeof buf, "%.50s %d %d",
1010 get_remote_ipaddr(), get_remote_port(), get_local_port());
1011 child_set_env(&env, &envsize, "SSH_CLIENT", buf);
1014 child_set_env(&env, &envsize, "SSH_TTY", s->tty);
1016 child_set_env(&env, &envsize, "TERM", s->term);
1018 child_set_env(&env, &envsize, "DISPLAY", s->display);
1019 if (original_command)
1020 child_set_env(&env, &envsize, "SSH_ORIGINAL_COMMAND",
1027 if ((cp = getenv("AUTHSTATE")) != NULL)
1028 child_set_env(&env, &envsize, "AUTHSTATE", cp);
1029 if ((cp = getenv("KRB5CCNAME")) != NULL)
1030 child_set_env(&env, &envsize, "KRB5CCNAME", cp);
1031 read_environment_file(&env, &envsize, "/etc/environment");
1035 if (s->authctxt->krb4_ticket_file)
1036 child_set_env(&env, &envsize, "KRBTKFILE",
1037 s->authctxt->krb4_ticket_file);
1040 if (s->authctxt->krb5_ticket_file)
1041 child_set_env(&env, &envsize, "KRB5CCNAME",
1042 s->authctxt->krb5_ticket_file);
1045 /* Pull in any environment variables that may have been set by PAM. */
1046 copy_environment(fetch_pam_environment(), &env, &envsize);
1047 #endif /* USE_PAM */
1049 if (auth_sock_name != NULL)
1050 child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME,
1053 /* read $HOME/.ssh/environment. */
1054 if (!options.use_login) {
1055 snprintf(buf, sizeof buf, "%.200s/.ssh/environment",
1057 read_environment_file(&env, &envsize, buf);
1060 /* dump the environment */
1061 fprintf(stderr, "Environment:\n");
1062 for (i = 0; env[i]; i++)
1063 fprintf(stderr, " %.200s\n", env[i]);
1069 * Run $HOME/.ssh/rc, /etc/ssh/sshrc, or xauth (whichever is found
1070 * first in this order).
1073 do_rc_files(Session *s, const char *shell)
1081 s->display != NULL && s->auth_proto != NULL && s->auth_data != NULL;
1083 /* ignore _PATH_SSH_USER_RC for subsystems */
1084 if (!s->is_subsystem && (stat(_PATH_SSH_USER_RC, &st) >= 0)) {
1085 snprintf(cmd, sizeof cmd, "%s -c '%s %s'",
1086 shell, _PATH_BSHELL, _PATH_SSH_USER_RC);
1088 fprintf(stderr, "Running %s\n", cmd);
1089 f = popen(cmd, "w");
1092 fprintf(f, "%s %s\n", s->auth_proto,
1096 fprintf(stderr, "Could not run %s\n",
1098 } else if (stat(_PATH_SSH_SYSTEM_RC, &st) >= 0) {
1100 fprintf(stderr, "Running %s %s\n", _PATH_BSHELL,
1101 _PATH_SSH_SYSTEM_RC);
1102 f = popen(_PATH_BSHELL " " _PATH_SSH_SYSTEM_RC, "w");
1105 fprintf(f, "%s %s\n", s->auth_proto,
1109 fprintf(stderr, "Could not run %s\n",
1110 _PATH_SSH_SYSTEM_RC);
1111 } else if (do_xauth && options.xauth_location != NULL) {
1112 /* Add authority data to .Xauthority if appropriate. */
1115 "Running %.500s add "
1116 "%.100s %.100s %.100s\n",
1117 options.xauth_location, s->auth_display,
1118 s->auth_proto, s->auth_data);
1120 snprintf(cmd, sizeof cmd, "%s -q -",
1121 options.xauth_location);
1122 f = popen(cmd, "w");
1124 fprintf(f, "add %s %s %s\n",
1125 s->auth_display, s->auth_proto,
1129 fprintf(stderr, "Could not run %s\n",
1136 do_nologin(struct passwd *pw)
1141 #ifdef HAVE_LOGIN_CAP
1142 if (!login_getcapbool(lc, "ignorenologin", 0) && pw->pw_uid)
1143 f = fopen(login_getcapstr(lc, "nologin", _PATH_NOLOGIN,
1144 _PATH_NOLOGIN), "r");
1147 f = fopen(_PATH_NOLOGIN, "r");
1150 /* /etc/nologin exists. Print its contents and exit. */
1151 while (fgets(buf, sizeof(buf), f))
1158 /* Set login name, uid, gid, and groups. */
1160 do_setusercontext(struct passwd *pw)
1166 #else /* HAVE_CYGWIN */
1167 if (getuid() == 0 || geteuid() == 0) {
1168 #endif /* HAVE_CYGWIN */
1169 #ifdef HAVE_SETPCRED
1170 setpcred(pw->pw_name);
1171 #endif /* HAVE_SETPCRED */
1172 #ifdef HAVE_LOGIN_CAP
1176 if (setusercontext(lc, pw, pw->pw_uid,
1177 (LOGIN_SETALL & ~LOGIN_SETPATH)) < 0) {
1178 perror("unable to set user context");
1182 # if defined(HAVE_GETLUID) && defined(HAVE_SETLUID)
1183 /* Sets login uid for accounting */
1184 if (getluid() == -1 && setluid(pw->pw_uid) == -1)
1185 error("setluid: %s", strerror(errno));
1186 # endif /* defined(HAVE_GETLUID) && defined(HAVE_SETLUID) */
1188 if (setlogin(pw->pw_name) < 0)
1189 error("setlogin failed: %s", strerror(errno));
1190 if (setgid(pw->pw_gid) < 0) {
1194 /* Initialize the group list. */
1195 if (initgroups(pw->pw_name, pw->pw_gid) < 0) {
1196 perror("initgroups");
1202 * PAM credentials may take the form of supplementary groups.
1203 * These will have been wiped by the above initgroups() call.
1204 * Reestablish them here.
1207 # endif /* USE_PAM */
1208 # if defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY)
1209 irix_setusercontext(pw);
1210 # endif /* defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) */
1214 /* Permanently switch to the desired uid. */
1215 permanently_set_uid(pw);
1218 if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid)
1219 fatal("Failed to set uids to %u.", (u_int) pw->pw_uid);
1223 launch_login(struct passwd *pw, const char *hostname)
1225 /* Launch login(1). */
1227 execl(LOGIN_PROGRAM, "login", "-h", hostname,
1228 #ifdef xxxLOGIN_NEEDS_TERM
1229 (s->term ? s->term : "unknown"),
1230 #endif /* LOGIN_NEEDS_TERM */
1231 #ifdef LOGIN_NO_ENDOPT
1232 "-p", "-f", pw->pw_name, (char *)NULL);
1234 "-p", "-f", "--", pw->pw_name, (char *)NULL);
1237 /* Login couldn't be executed, die. */
1244 * Performs common processing for the child, such as setting up the
1245 * environment, closing extra file descriptors, setting the user and group
1246 * ids, and executing the command or shell.
1249 do_child(Session *s, const char *command)
1251 extern char **environ;
1254 const char *shell, *shell0, *hostname = NULL;
1255 struct passwd *pw = s->pw;
1258 /* remove hostkey from the child's memory */
1259 destroy_sensitive_data();
1261 /* login(1) is only called if we execute the login shell */
1262 if (options.use_login && command != NULL)
1263 options.use_login = 0;
1266 * Login(1) does this as well, and it needs uid 0 for the "-h"
1267 * switch, so we let login(1) to this for us.
1269 if (!options.use_login) {
1271 session_setup_sia(pw->pw_name, s->ttyfd == -1 ? NULL : s->tty);
1272 if (!check_quietlogin(s, command))
1274 #else /* HAVE_OSF_SIA */
1276 do_setusercontext(pw);
1277 #endif /* HAVE_OSF_SIA */
1281 * Get the shell from the password data. An empty shell field is
1282 * legal, and means /bin/sh.
1284 shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
1285 #ifdef HAVE_LOGIN_CAP
1286 shell = login_getcapstr(lc, "shell", (char *)shell, (char *)shell);
1289 env = do_setup_env(s, shell);
1291 /* we have to stash the hostname before we close our socket. */
1292 if (options.use_login)
1293 hostname = get_remote_name_or_ip(utmp_len,
1294 options.verify_reverse_mapping);
1296 * Close the connection descriptors; note that this is the child, and
1297 * the server will still have the socket open, and it is important
1298 * that we do not shutdown it. Note that the descriptors cannot be
1299 * closed before building the environment, as we call
1300 * get_remote_ipaddr there.
1302 if (packet_get_connection_in() == packet_get_connection_out())
1303 close(packet_get_connection_in());
1305 close(packet_get_connection_in());
1306 close(packet_get_connection_out());
1309 * Close all descriptors related to channels. They will still remain
1310 * open in the parent.
1312 /* XXX better use close-on-exec? -markus */
1313 channel_close_all();
1316 * Close any extra file descriptors. Note that there may still be
1317 * descriptors left by system functions. They will be closed later.
1322 * Close any extra open file descriptors so that we don\'t have them
1323 * hanging around in clients. Note that we want to do this after
1324 * initgroups, because at least on Solaris 2.3 it leaves file
1327 for (i = 3; i < 64; i++)
1331 * Must take new environment into use so that .ssh/rc,
1332 * /etc/ssh/sshrc and xauth are run in the proper environment.
1337 /* Try to get AFS tokens for the local cell. */
1341 if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0)
1342 krb_afslog(cell, 0);
1348 /* Change current directory to the user\'s home directory. */
1349 if (chdir(pw->pw_dir) < 0) {
1350 fprintf(stderr, "Could not chdir to home directory %s: %s\n",
1351 pw->pw_dir, strerror(errno));
1352 #ifdef HAVE_LOGIN_CAP
1353 if (login_getcapbool(lc, "requirehome", 0))
1358 if (!options.use_login)
1359 do_rc_files(s, shell);
1361 /* restore SIGPIPE for child */
1362 signal(SIGPIPE, SIG_DFL);
1364 if (options.use_login) {
1365 launch_login(pw, hostname);
1369 /* Get the last component of the shell name. */
1370 if ((shell0 = strrchr(shell, '/')) != NULL)
1376 * If we have no command, execute the shell. In this case, the shell
1377 * name to be passed in argv[0] is preceded by '-' to indicate that
1378 * this is a login shell.
1383 /* Start the shell. Set initial character to '-'. */
1386 if (strlcpy(argv0 + 1, shell0, sizeof(argv0) - 1)
1387 >= sizeof(argv0) - 1) {
1393 /* Execute the shell. */
1396 execve(shell, argv, env);
1398 /* Executing the shell failed. */
1403 * Execute the command using the user's shell. This uses the -c
1404 * option to execute the command.
1406 argv[0] = (char *) shell0;
1408 argv[2] = (char *) command;
1410 execve(shell, argv, env);
1419 static int did_init = 0;
1421 debug("session_new: init");
1422 for (i = 0; i < MAX_SESSIONS; i++) {
1423 sessions[i].used = 0;
1427 for (i = 0; i < MAX_SESSIONS; i++) {
1428 Session *s = &sessions[i];
1430 memset(s, 0, sizeof(*s));
1436 debug("session_new: session %d", i);
1447 for (i = 0; i < MAX_SESSIONS; i++) {
1448 Session *s = &sessions[i];
1449 debug("dump: used %d session %d %p channel %d pid %ld",
1459 session_open(Authctxt *authctxt, int chanid)
1461 Session *s = session_new();
1462 debug("session_open: channel %d", chanid);
1464 error("no more sessions");
1467 s->authctxt = authctxt;
1468 s->pw = authctxt->pw;
1470 fatal("no user for session %d", s->self);
1471 debug("session_open: session %d: link with channel %d", s->self, chanid);
1477 session_by_tty(char *tty)
1480 for (i = 0; i < MAX_SESSIONS; i++) {
1481 Session *s = &sessions[i];
1482 if (s->used && s->ttyfd != -1 && strcmp(s->tty, tty) == 0) {
1483 debug("session_by_tty: session %d tty %s", i, tty);
1487 debug("session_by_tty: unknown tty %.100s", tty);
1493 session_by_channel(int id)
1496 for (i = 0; i < MAX_SESSIONS; i++) {
1497 Session *s = &sessions[i];
1498 if (s->used && s->chanid == id) {
1499 debug("session_by_channel: session %d channel %d", i, id);
1503 debug("session_by_channel: unknown channel %d", id);
1509 session_by_pid(pid_t pid)
1512 debug("session_by_pid: pid %ld", (long)pid);
1513 for (i = 0; i < MAX_SESSIONS; i++) {
1514 Session *s = &sessions[i];
1515 if (s->used && s->pid == pid)
1518 error("session_by_pid: unknown pid %ld", (long)pid);
1524 session_window_change_req(Session *s)
1526 s->col = packet_get_int();
1527 s->row = packet_get_int();
1528 s->xpixel = packet_get_int();
1529 s->ypixel = packet_get_int();
1531 pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1536 session_pty_req(Session *s)
1542 debug("Allocating a pty not permitted for this authentication.");
1545 if (s->ttyfd != -1) {
1546 packet_disconnect("Protocol error: you already have a pty.");
1549 /* Get the time and hostname when the user last logged in. */
1550 if (options.print_lastlog) {
1551 s->hostname[0] = '\0';
1552 s->last_login_time = get_last_login_time(s->pw->pw_uid,
1553 s->pw->pw_name, s->hostname, sizeof(s->hostname));
1556 s->term = packet_get_string(&len);
1559 s->col = packet_get_int();
1560 s->row = packet_get_int();
1562 s->row = packet_get_int();
1563 s->col = packet_get_int();
1565 s->xpixel = packet_get_int();
1566 s->ypixel = packet_get_int();
1568 if (strcmp(s->term, "") == 0) {
1573 /* Allocate a pty and open it. */
1574 debug("Allocating pty.");
1575 if (!PRIVSEP(pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty)))) {
1581 error("session_pty_req: session %d alloc failed", s->self);
1584 debug("session_pty_req: session %d alloc %s", s->self, s->tty);
1586 /* for SSH1 the tty modes length is not given */
1588 n_bytes = packet_remaining();
1589 tty_parse_modes(s->ttyfd, &n_bytes);
1592 * Add a cleanup function to clear the utmp entry and record logout
1593 * time in case we call fatal() (e.g., the connection gets closed).
1595 fatal_add_cleanup(session_pty_cleanup, (void *)s);
1597 pty_setowner(s->pw, s->tty);
1599 /* Set window size from the packet. */
1600 pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1603 session_proctitle(s);
1608 session_subsystem_req(Session *s)
1613 char *cmd, *subsys = packet_get_string(&len);
1617 log("subsystem request for %.100s", subsys);
1619 for (i = 0; i < options.num_subsystems; i++) {
1620 if (strcmp(subsys, options.subsystem_name[i]) == 0) {
1621 cmd = options.subsystem_command[i];
1622 if (stat(cmd, &st) < 0) {
1623 error("subsystem: cannot stat %s: %s", cmd,
1627 debug("subsystem: exec() %s", cmd);
1628 s->is_subsystem = 1;
1636 log("subsystem request for %.100s failed, subsystem not found",
1644 session_x11_req(Session *s)
1648 s->single_connection = packet_get_char();
1649 s->auth_proto = packet_get_string(NULL);
1650 s->auth_data = packet_get_string(NULL);
1651 s->screen = packet_get_int();
1654 success = session_setup_x11fwd(s);
1656 xfree(s->auth_proto);
1657 xfree(s->auth_data);
1658 s->auth_proto = NULL;
1659 s->auth_data = NULL;
1665 session_shell_req(Session *s)
1673 session_exec_req(Session *s)
1676 char *command = packet_get_string(&len);
1678 do_exec(s, command);
1684 session_auth_agent_req(Session *s)
1686 static int called = 0;
1688 if (no_agent_forwarding_flag) {
1689 debug("session_auth_agent_req: no_agent_forwarding_flag");
1696 return auth_input_request_forwarding(s->pw);
1701 session_input_channel_req(Channel *c, const char *rtype)
1706 if ((s = session_by_channel(c->self)) == NULL) {
1707 log("session_input_channel_req: no session %d req %.100s",
1711 debug("session_input_channel_req: session %d req %s", s->self, rtype);
1714 * a session is in LARVAL state until a shell, a command
1715 * or a subsystem is executed
1717 if (c->type == SSH_CHANNEL_LARVAL) {
1718 if (strcmp(rtype, "shell") == 0) {
1719 success = session_shell_req(s);
1720 } else if (strcmp(rtype, "exec") == 0) {
1721 success = session_exec_req(s);
1722 } else if (strcmp(rtype, "pty-req") == 0) {
1723 success = session_pty_req(s);
1724 } else if (strcmp(rtype, "x11-req") == 0) {
1725 success = session_x11_req(s);
1726 } else if (strcmp(rtype, "auth-agent-req@openssh.com") == 0) {
1727 success = session_auth_agent_req(s);
1728 } else if (strcmp(rtype, "subsystem") == 0) {
1729 success = session_subsystem_req(s);
1732 if (strcmp(rtype, "window-change") == 0) {
1733 success = session_window_change_req(s);
1739 session_set_fds(Session *s, int fdin, int fdout, int fderr)
1742 fatal("session_set_fds: called for proto != 2.0");
1744 * now that have a child and a pipe to the child,
1745 * we can activate our channel and register the fd's
1747 if (s->chanid == -1)
1748 fatal("no channel for session %d", s->self);
1749 channel_set_fds(s->chanid,
1751 fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ,
1753 CHAN_SES_WINDOW_DEFAULT);
1757 * Function to perform pty cleanup. Also called if we get aborted abnormally
1758 * (e.g., due to a dropped connection).
1761 session_pty_cleanup2(void *session)
1763 Session *s = session;
1766 error("session_pty_cleanup: no session");
1772 debug("session_pty_cleanup: session %d release %s", s->self, s->tty);
1774 /* Record that the user has logged out. */
1776 record_logout(s->pid, s->tty, s->pw->pw_name);
1778 /* Release the pseudo-tty. */
1780 pty_release(s->tty);
1783 * Close the server side of the socket pairs. We must do this after
1784 * the pty cleanup, so that another process doesn't get this pty
1785 * while we're still cleaning up.
1787 if (close(s->ptymaster) < 0)
1788 error("close(s->ptymaster/%d): %s", s->ptymaster, strerror(errno));
1790 /* unlink pty from session */
1795 session_pty_cleanup(void *session)
1797 PRIVSEP(session_pty_cleanup2(session));
1801 session_exit_message(Session *s, int status)
1805 if ((c = channel_lookup(s->chanid)) == NULL)
1806 fatal("session_exit_message: session %d: no channel %d",
1807 s->self, s->chanid);
1808 debug("session_exit_message: session %d channel %d pid %ld",
1809 s->self, s->chanid, (long)s->pid);
1811 if (WIFEXITED(status)) {
1812 channel_request_start(s->chanid, "exit-status", 0);
1813 packet_put_int(WEXITSTATUS(status));
1815 } else if (WIFSIGNALED(status)) {
1816 channel_request_start(s->chanid, "exit-signal", 0);
1817 packet_put_int(WTERMSIG(status));
1819 packet_put_char(WCOREDUMP(status));
1820 #else /* WCOREDUMP */
1822 #endif /* WCOREDUMP */
1823 packet_put_cstring("");
1824 packet_put_cstring("");
1827 /* Some weird exit cause. Just exit. */
1828 packet_disconnect("wait returned status %04x.", status);
1831 /* disconnect channel */
1832 debug("session_exit_message: release channel %d", s->chanid);
1833 channel_cancel_cleanup(s->chanid);
1835 * emulate a write failure with 'chan_write_failed', nobody will be
1836 * interested in data we write.
1837 * Note that we must not call 'chan_read_failed', since there could
1838 * be some more data waiting in the pipe.
1840 if (c->ostate != CHAN_OUTPUT_CLOSED)
1841 chan_write_failed(c);
1846 session_close(Session *s)
1848 debug("session_close: session %d pid %ld", s->self, (long)s->pid);
1849 if (s->ttyfd != -1) {
1850 fatal_remove_cleanup(session_pty_cleanup, (void *)s);
1851 session_pty_cleanup(s);
1857 if (s->auth_display)
1858 xfree(s->auth_display);
1860 xfree(s->auth_data);
1862 xfree(s->auth_proto);
1864 session_proctitle(s);
1868 session_close_by_pid(pid_t pid, int status)
1870 Session *s = session_by_pid(pid);
1872 debug("session_close_by_pid: no session for pid %ld",
1876 if (s->chanid != -1)
1877 session_exit_message(s, status);
1882 * this is called when a channel dies before
1883 * the session 'child' itself dies
1886 session_close_by_channel(int id, void *arg)
1888 Session *s = session_by_channel(id);
1890 debug("session_close_by_channel: no session for id %d", id);
1893 debug("session_close_by_channel: channel %d child %ld",
1896 debug("session_close_by_channel: channel %d: has child", id);
1898 * delay detach of session, but release pty, since
1899 * the fd's to the child are already closed
1901 if (s->ttyfd != -1) {
1902 fatal_remove_cleanup(session_pty_cleanup, (void *)s);
1903 session_pty_cleanup(s);
1907 /* detach by removing callback */
1908 channel_cancel_cleanup(s->chanid);
1914 session_destroy_all(void (*closefunc)(Session *))
1917 for (i = 0; i < MAX_SESSIONS; i++) {
1918 Session *s = &sessions[i];
1920 if (closefunc != NULL)
1929 session_tty_list(void)
1931 static char buf[1024];
1934 for (i = 0; i < MAX_SESSIONS; i++) {
1935 Session *s = &sessions[i];
1936 if (s->used && s->ttyfd != -1) {
1938 strlcat(buf, ",", sizeof buf);
1939 strlcat(buf, strrchr(s->tty, '/') + 1, sizeof buf);
1943 strlcpy(buf, "notty", sizeof buf);
1948 session_proctitle(Session *s)
1951 error("no user for session %d", s->self);
1953 setproctitle("%s@%s", s->pw->pw_name, session_tty_list());
1957 session_setup_x11fwd(Session *s)
1960 char display[512], auth_display[512];
1961 char hostname[MAXHOSTNAMELEN];
1963 if (no_x11_forwarding_flag) {
1964 packet_send_debug("X11 forwarding disabled in user configuration file.");
1967 if (!options.x11_forwarding) {
1968 debug("X11 forwarding disabled in server configuration file.");
1971 if (!options.xauth_location ||
1972 (stat(options.xauth_location, &st) == -1)) {
1973 packet_send_debug("No xauth program; cannot forward with spoofing.");
1976 if (options.use_login) {
1977 packet_send_debug("X11 forwarding disabled; "
1978 "not compatible with UseLogin=yes.");
1981 if (s->display != NULL) {
1982 debug("X11 display already set.");
1985 if (x11_create_display_inet(options.x11_display_offset,
1986 options.x11_use_localhost, s->single_connection,
1987 &s->display_number) == -1) {
1988 debug("x11_create_display_inet failed.");
1992 /* Set up a suitable value for the DISPLAY variable. */
1993 if (gethostname(hostname, sizeof(hostname)) < 0)
1994 fatal("gethostname: %.100s", strerror(errno));
1996 * auth_display must be used as the displayname when the
1997 * authorization entry is added with xauth(1). This will be
1998 * different than the DISPLAY string for localhost displays.
2000 if (options.x11_use_localhost) {
2001 snprintf(display, sizeof display, "localhost:%u.%u",
2002 s->display_number, s->screen);
2003 snprintf(auth_display, sizeof auth_display, "unix:%u.%u",
2004 s->display_number, s->screen);
2005 s->display = xstrdup(display);
2006 s->auth_display = xstrdup(auth_display);
2008 #ifdef IPADDR_IN_DISPLAY
2010 struct in_addr my_addr;
2012 he = gethostbyname(hostname);
2014 error("Can't get IP address for X11 DISPLAY.");
2015 packet_send_debug("Can't get IP address for X11 DISPLAY.");
2018 memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr));
2019 snprintf(display, sizeof display, "%.50s:%u.%u", inet_ntoa(my_addr),
2020 s->display_number, s->screen);
2022 snprintf(display, sizeof display, "%.400s:%u.%u", hostname,
2023 s->display_number, s->screen);
2025 s->display = xstrdup(display);
2026 s->auth_display = xstrdup(display);
2033 do_authenticated2(Authctxt *authctxt)
2035 server_loop2(authctxt);