Annotation of src/usr.bin/ssh/session.c, Revision 1.226
1.226 ! djm 1: /* $OpenBSD: session.c,v 1.225 2008/02/04 21:53:00 markus Exp $ */
1.1 markus 2: /*
3: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
4: * All rights reserved
1.37 deraadt 5: *
6: * As far as I am concerned, the code I have written for this software
7: * can be used freely for any purpose. Any derived versions of this
8: * software must be clearly marked as such, and if the derived work is
9: * incompatible with the protocol description in the RFC file, it must be
10: * called by a name other than "ssh" or "Secure Shell".
11: *
1.2 markus 12: * SSH2 support by Markus Friedl.
1.95 markus 13: * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
1.37 deraadt 14: *
15: * Redistribution and use in source and binary forms, with or without
16: * modification, are permitted provided that the following conditions
17: * are met:
18: * 1. Redistributions of source code must retain the above copyright
19: * notice, this list of conditions and the following disclaimer.
20: * 2. Redistributions in binary form must reproduce the above copyright
21: * notice, this list of conditions and the following disclaimer in the
22: * documentation and/or other materials provided with the distribution.
23: *
24: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
25: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
28: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
29: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
30: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
31: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
32: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
33: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.2 markus 34: */
1.1 markus 35:
1.193 stevesk 36: #include <sys/types.h>
37: #include <sys/wait.h>
1.194 stevesk 38: #include <sys/un.h>
1.196 stevesk 39: #include <sys/stat.h>
1.207 stevesk 40: #include <sys/socket.h>
1.213 stevesk 41: #include <sys/param.h>
1.192 stevesk 42:
1.209 stevesk 43: #include <errno.h>
1.204 stevesk 44: #include <grp.h>
1.223 djm 45: #include <login_cap.h>
1.192 stevesk 46: #include <paths.h>
1.206 stevesk 47: #include <pwd.h>
1.195 stevesk 48: #include <signal.h>
1.215 stevesk 49: #include <stdio.h>
1.214 stevesk 50: #include <stdlib.h>
1.212 stevesk 51: #include <string.h>
1.211 stevesk 52: #include <unistd.h>
1.1 markus 53:
1.216 deraadt 54: #include "xmalloc.h"
1.51 markus 55: #include "ssh.h"
56: #include "ssh1.h"
57: #include "ssh2.h"
1.59 djm 58: #include "sshpty.h"
1.1 markus 59: #include "packet.h"
60: #include "buffer.h"
1.173 djm 61: #include "match.h"
1.1 markus 62: #include "uidswap.h"
63: #include "compat.h"
1.78 markus 64: #include "channels.h"
1.216 deraadt 65: #include "key.h"
66: #include "cipher.h"
67: #include "kex.h"
68: #include "hostfile.h"
1.2 markus 69: #include "auth.h"
1.19 markus 70: #include "auth-options.h"
1.50 markus 71: #include "pathnames.h"
1.51 markus 72: #include "log.h"
73: #include "servconf.h"
1.59 djm 74: #include "sshlogin.h"
1.51 markus 75: #include "serverloop.h"
76: #include "canohost.h"
1.226 ! djm 77: #include "misc.h"
1.55 itojun 78: #include "session.h"
1.216 deraadt 79: #ifdef GSSAPI
80: #include "ssh-gss.h"
81: #endif
1.130 provos 82: #include "monitor_wrap.h"
1.225 markus 83: #include "sftp.h"
1.171 markus 84:
85: #ifdef KRB5
86: #include <kafs.h>
1.161 markus 87: #endif
88:
1.226 ! djm 89: /* Magic name for internal sftp-server */
! 90: #define INTERNAL_SFTP_NAME "internal-sftp"
! 91:
1.1 markus 92: /* func */
93:
94: Session *session_new(void);
1.94 itojun 95: void session_set_fds(Session *, int, int, int);
1.165 markus 96: void session_pty_cleanup(Session *);
1.94 itojun 97: void session_proctitle(Session *);
98: int session_setup_x11fwd(Session *);
99: void do_exec_pty(Session *, const char *);
100: void do_exec_no_pty(Session *, const char *);
101: void do_exec(Session *, const char *);
102: void do_login(Session *, const char *);
103: void do_child(Session *, const char *);
1.73 djm 104: void do_motd(void);
1.94 itojun 105: int check_quietlogin(Session *, const char *);
1.1 markus 106:
1.94 itojun 107: static void do_authenticated1(Authctxt *);
108: static void do_authenticated2(Authctxt *);
109:
110: static int session_pty_req(Session *);
1.65 markus 111:
1.1 markus 112: /* import */
113: extern ServerOptions options;
114: extern char *__progname;
115: extern int log_stderr;
116: extern int debug_flag;
1.45 markus 117: extern u_int utmp_len;
1.21 markus 118: extern int startup_pipe;
1.74 markus 119: extern void destroy_sensitive_data(void);
1.179 dtucker 120: extern Buffer loginmsg;
1.21 markus 121:
1.34 markus 122: /* original command from peer. */
1.92 markus 123: const char *original_command = NULL;
1.34 markus 124:
1.1 markus 125: /* data */
126: #define MAX_SESSIONS 10
127: Session sessions[MAX_SESSIONS];
128:
1.225 markus 129: #define SUBSYSTEM_NONE 0
130: #define SUBSYSTEM_EXT 1
131: #define SUBSYSTEM_INT_SFTP 2
132:
1.129 provos 133: login_cap_t *lc;
1.28 millert 134:
1.165 markus 135: static int is_child = 0;
136:
1.136 markus 137: /* Name and directory of socket for authentication agent forwarding. */
138: static char *auth_sock_name = NULL;
139: static char *auth_sock_dir = NULL;
140:
141: /* removes the agent forwarding socket */
142:
143: static void
1.165 markus 144: auth_sock_cleanup_proc(struct passwd *pw)
1.136 markus 145: {
146: if (auth_sock_name != NULL) {
147: temporarily_use_uid(pw);
148: unlink(auth_sock_name);
149: rmdir(auth_sock_dir);
150: auth_sock_name = NULL;
151: restore_uid();
152: }
153: }
154:
155: static int
156: auth_input_request_forwarding(struct passwd * pw)
157: {
158: Channel *nc;
159: int sock;
160: struct sockaddr_un sunaddr;
161:
162: if (auth_sock_name != NULL) {
163: error("authentication forwarding requested twice.");
164: return 0;
165: }
166:
167: /* Temporarily drop privileged uid for mkdir/bind. */
168: temporarily_use_uid(pw);
169:
170: /* Allocate a buffer for the socket name, and format the name. */
171: auth_sock_name = xmalloc(MAXPATHLEN);
172: auth_sock_dir = xmalloc(MAXPATHLEN);
1.166 markus 173: strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN);
1.136 markus 174:
175: /* Create private directory for socket */
176: if (mkdtemp(auth_sock_dir) == NULL) {
177: packet_send_debug("Agent forwarding disabled: "
178: "mkdtemp() failed: %.100s", strerror(errno));
179: restore_uid();
180: xfree(auth_sock_name);
181: xfree(auth_sock_dir);
182: auth_sock_name = NULL;
183: auth_sock_dir = NULL;
184: return 0;
185: }
1.137 mpech 186: snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%ld",
187: auth_sock_dir, (long) getpid());
1.136 markus 188:
189: /* Create the socket. */
190: sock = socket(AF_UNIX, SOCK_STREAM, 0);
191: if (sock < 0)
192: packet_disconnect("socket: %.100s", strerror(errno));
193:
194: /* Bind it to the name. */
195: memset(&sunaddr, 0, sizeof(sunaddr));
196: sunaddr.sun_family = AF_UNIX;
197: strlcpy(sunaddr.sun_path, auth_sock_name, sizeof(sunaddr.sun_path));
198:
1.200 deraadt 199: if (bind(sock, (struct sockaddr *)&sunaddr, sizeof(sunaddr)) < 0)
1.136 markus 200: packet_disconnect("bind: %.100s", strerror(errno));
201:
202: /* Restore the privileged uid. */
203: restore_uid();
204:
205: /* Start listening on the socket. */
1.169 markus 206: if (listen(sock, SSH_LISTEN_BACKLOG) < 0)
1.136 markus 207: packet_disconnect("listen: %.100s", strerror(errno));
208:
209: /* Allocate a channel for the authentication agent socket. */
210: nc = channel_new("auth socket",
211: SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1,
212: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.156 markus 213: 0, "auth socket", 1);
1.136 markus 214: strlcpy(nc->path, auth_sock_name, sizeof(nc->path));
215: return 1;
216: }
217:
1.179 dtucker 218: static void
219: display_loginmsg(void)
220: {
1.183 djm 221: if (buffer_len(&loginmsg) > 0) {
222: buffer_append(&loginmsg, "\0", 1);
223: printf("%s", (char *)buffer_ptr(&loginmsg));
224: buffer_clear(&loginmsg);
225: }
1.179 dtucker 226: }
1.136 markus 227:
1.65 markus 228: void
229: do_authenticated(Authctxt *authctxt)
230: {
1.153 markus 231: setproctitle("%s", authctxt->pw->pw_name);
232:
1.65 markus 233: /* setup the channel layer */
234: if (!no_port_forwarding_flag && options.allow_tcp_forwarding)
235: channel_permit_all_opens();
236:
237: if (compat20)
238: do_authenticated2(authctxt);
239: else
240: do_authenticated1(authctxt);
1.79 markus 241:
1.165 markus 242: do_cleanup(authctxt);
1.65 markus 243: }
244:
1.1 markus 245: /*
246: * Prepares for an interactive session. This is called after the user has
247: * been successfully authenticated. During this message exchange, pseudo
248: * terminals are allocated, X11, TCP/IP, and authentication agent forwardings
249: * are requested, etc.
250: */
1.94 itojun 251: static void
1.65 markus 252: do_authenticated1(Authctxt *authctxt)
1.1 markus 253: {
254: Session *s;
1.65 markus 255: char *command;
1.117 markus 256: int success, type, screen_flag;
1.139 deraadt 257: int enable_compression_after_reply = 0;
258: u_int proto_len, data_len, dlen, compression_level = 0;
1.1 markus 259:
1.61 markus 260: s = session_new();
1.181 markus 261: if (s == NULL) {
262: error("no more sessions");
263: return;
264: }
1.96 dugsong 265: s->authctxt = authctxt;
1.65 markus 266: s->pw = authctxt->pw;
1.28 millert 267:
1.1 markus 268: /*
269: * We stay in this loop until the client requests to execute a shell
270: * or a command.
271: */
272: for (;;) {
1.65 markus 273: success = 0;
1.1 markus 274:
275: /* Get a packet from the client. */
1.117 markus 276: type = packet_read();
1.1 markus 277:
278: /* Process the packet. */
279: switch (type) {
280: case SSH_CMSG_REQUEST_COMPRESSION:
281: compression_level = packet_get_int();
1.116 markus 282: packet_check_eom();
1.1 markus 283: if (compression_level < 1 || compression_level > 9) {
1.180 markus 284: packet_send_debug("Received invalid compression level %d.",
1.112 deraadt 285: compression_level);
1.138 markus 286: break;
287: }
1.186 markus 288: if (options.compression == COMP_NONE) {
1.138 markus 289: debug2("compression disabled");
1.1 markus 290: break;
291: }
292: /* Enable compression after we have responded with SUCCESS. */
293: enable_compression_after_reply = 1;
294: success = 1;
295: break;
296:
297: case SSH_CMSG_REQUEST_PTY:
1.86 markus 298: success = session_pty_req(s);
1.1 markus 299: break;
300:
301: case SSH_CMSG_X11_REQUEST_FORWARDING:
302: s->auth_proto = packet_get_string(&proto_len);
303: s->auth_data = packet_get_string(&data_len);
304:
1.57 markus 305: screen_flag = packet_get_protocol_flags() &
306: SSH_PROTOFLAG_SCREEN_NUMBER;
307: debug2("SSH_PROTOFLAG_SCREEN_NUMBER: %d", screen_flag);
308:
309: if (packet_remaining() == 4) {
310: if (!screen_flag)
311: debug2("Buggy client: "
312: "X11 screen flag missing");
1.1 markus 313: s->screen = packet_get_int();
1.56 markus 314: } else {
1.1 markus 315: s->screen = 0;
1.56 markus 316: }
1.116 markus 317: packet_check_eom();
1.81 markus 318: success = session_setup_x11fwd(s);
319: if (!success) {
320: xfree(s->auth_proto);
321: xfree(s->auth_data);
1.84 markus 322: s->auth_proto = NULL;
323: s->auth_data = NULL;
1.1 markus 324: }
325: break;
326:
327: case SSH_CMSG_AGENT_REQUEST_FORWARDING:
328: if (no_agent_forwarding_flag || compat13) {
329: debug("Authentication agent forwarding not permitted for this authentication.");
330: break;
331: }
332: debug("Received authentication agent forwarding request.");
1.65 markus 333: success = auth_input_request_forwarding(s->pw);
1.1 markus 334: break;
335:
336: case SSH_CMSG_PORT_FORWARD_REQUEST:
337: if (no_port_forwarding_flag) {
338: debug("Port forwarding not permitted for this authentication.");
1.39 markus 339: break;
340: }
341: if (!options.allow_tcp_forwarding) {
342: debug("Port forwarding not permitted.");
1.1 markus 343: break;
344: }
345: debug("Received TCP/IP port forwarding request.");
1.208 markus 346: if (channel_input_port_forward_request(s->pw->pw_uid == 0,
347: options.gateway_ports) < 0) {
348: debug("Port forwarding failed.");
349: break;
350: }
1.1 markus 351: success = 1;
352: break;
353:
354: case SSH_CMSG_MAX_PACKET_SIZE:
355: if (packet_set_maxsize(packet_get_int()) > 0)
356: success = 1;
357: break;
358:
359: case SSH_CMSG_EXEC_SHELL:
360: case SSH_CMSG_EXEC_CMD:
361: if (type == SSH_CMSG_EXEC_CMD) {
362: command = packet_get_string(&dlen);
363: debug("Exec command '%.500s'", command);
1.92 markus 364: do_exec(s, command);
365: xfree(command);
1.1 markus 366: } else {
1.92 markus 367: do_exec(s, NULL);
1.1 markus 368: }
1.116 markus 369: packet_check_eom();
1.82 markus 370: session_close(s);
1.1 markus 371: return;
372:
373: default:
374: /*
375: * Any unknown messages in this phase are ignored,
376: * and a failure message is returned.
377: */
1.155 itojun 378: logit("Unknown packet type received after authentication: %d", type);
1.1 markus 379: }
380: packet_start(success ? SSH_SMSG_SUCCESS : SSH_SMSG_FAILURE);
381: packet_send();
382: packet_write_wait();
383:
384: /* Enable compression now that we have replied if appropriate. */
385: if (enable_compression_after_reply) {
386: enable_compression_after_reply = 0;
387: packet_start_compression(compression_level);
388: }
389: }
390: }
391:
392: /*
393: * This is called to fork and execute a command when we have no tty. This
394: * will call do_child from the child, and server_loop from the parent after
395: * setting up file descriptors and such.
396: */
1.4 markus 397: void
1.63 markus 398: do_exec_no_pty(Session *s, const char *command)
1.1 markus 399: {
1.137 mpech 400: pid_t pid;
1.1 markus 401:
402: int inout[2], err[2];
403: /* Uses socket pairs to communicate with the program. */
404: if (socketpair(AF_UNIX, SOCK_STREAM, 0, inout) < 0 ||
405: socketpair(AF_UNIX, SOCK_STREAM, 0, err) < 0)
406: packet_disconnect("Could not create socket pairs: %.100s",
407: strerror(errno));
408: if (s == NULL)
409: fatal("do_exec_no_pty: no session");
410:
1.9 markus 411: session_proctitle(s);
1.1 markus 412:
413: /* Fork the child. */
414: if ((pid = fork()) == 0) {
1.165 markus 415: is_child = 1;
1.144 markus 416:
1.1 markus 417: /* Child. Reinitialize the log since the pid has changed. */
418: log_init(__progname, options.log_level, options.log_facility, log_stderr);
419:
420: /*
421: * Create a new session and process group since the 4.4BSD
422: * setlogin() affects the entire process group.
423: */
424: if (setsid() < 0)
425: error("setsid failed: %.100s", strerror(errno));
426:
427: /*
428: * Redirect stdin, stdout, and stderr. Stdin and stdout will
429: * use the same socket, as some programs (particularly rdist)
430: * seem to depend on it.
431: */
432: close(inout[1]);
433: close(err[1]);
434: if (dup2(inout[0], 0) < 0) /* stdin */
435: perror("dup2 stdin");
436: if (dup2(inout[0], 1) < 0) /* stdout. Note: same socket as stdin. */
437: perror("dup2 stdout");
438: if (dup2(err[0], 2) < 0) /* stderr */
439: perror("dup2 stderr");
440:
441: /* Do processing for the child (exec command etc). */
1.60 markus 442: do_child(s, command);
1.1 markus 443: /* NOTREACHED */
444: }
445: if (pid < 0)
446: packet_disconnect("fork failed: %.100s", strerror(errno));
447: s->pid = pid;
1.47 markus 448: /* Set interactive/non-interactive mode. */
1.48 markus 449: packet_set_interactive(s->display != NULL);
1.1 markus 450:
451: /* We are the parent. Close the child sides of the socket pairs. */
452: close(inout[0]);
453: close(err[0]);
454:
455: /*
456: * Enter the interactive session. Note: server_loop must be able to
457: * handle the case that fdin and fdout are the same.
458: */
1.2 markus 459: if (compat20) {
1.64 markus 460: session_set_fds(s, inout[1], inout[1], s->is_subsystem ? -1 : err[1]);
1.2 markus 461: } else {
462: server_loop(pid, inout[1], inout[1], err[1]);
463: /* server_loop has closed inout[1] and err[1]. */
464: }
1.1 markus 465: }
466:
467: /*
468: * This is called to fork and execute a command when we have a tty. This
469: * will call do_child from the child, and server_loop from the parent after
470: * setting up file descriptors, controlling tty, updating wtmp, utmp,
471: * lastlog, and other such operations.
472: */
1.4 markus 473: void
1.63 markus 474: do_exec_pty(Session *s, const char *command)
1.1 markus 475: {
476: int fdout, ptyfd, ttyfd, ptymaster;
477: pid_t pid;
478:
479: if (s == NULL)
480: fatal("do_exec_pty: no session");
481: ptyfd = s->ptyfd;
482: ttyfd = s->ttyfd;
483:
484: /* Fork the child. */
485: if ((pid = fork()) == 0) {
1.165 markus 486: is_child = 1;
1.97 markus 487:
1.24 markus 488: /* Child. Reinitialize the log because the pid has changed. */
1.1 markus 489: log_init(__progname, options.log_level, options.log_facility, log_stderr);
490: /* Close the master side of the pseudo tty. */
491: close(ptyfd);
492:
493: /* Make the pseudo tty our controlling tty. */
494: pty_make_controlling_tty(&ttyfd, s->tty);
495:
1.103 markus 496: /* Redirect stdin/stdout/stderr from the pseudo tty. */
497: if (dup2(ttyfd, 0) < 0)
498: error("dup2 stdin: %s", strerror(errno));
499: if (dup2(ttyfd, 1) < 0)
500: error("dup2 stdout: %s", strerror(errno));
501: if (dup2(ttyfd, 2) < 0)
502: error("dup2 stderr: %s", strerror(errno));
1.1 markus 503:
504: /* Close the extra descriptor for the pseudo tty. */
505: close(ttyfd);
506:
1.24 markus 507: /* record login, etc. similar to login(1) */
1.41 markus 508: if (!(options.use_login && command == NULL))
509: do_login(s, command);
1.1 markus 510:
511: /* Do common processing for the child, such as execing the command. */
1.60 markus 512: do_child(s, command);
1.1 markus 513: /* NOTREACHED */
514: }
515: if (pid < 0)
516: packet_disconnect("fork failed: %.100s", strerror(errno));
517: s->pid = pid;
518:
519: /* Parent. Close the slave side of the pseudo tty. */
520: close(ttyfd);
521:
522: /*
523: * Create another descriptor of the pty master side for use as the
524: * standard input. We could use the original descriptor, but this
525: * simplifies code in server_loop. The descriptor is bidirectional.
526: */
527: fdout = dup(ptyfd);
528: if (fdout < 0)
529: packet_disconnect("dup #1 failed: %.100s", strerror(errno));
530:
531: /* we keep a reference to the pty master */
532: ptymaster = dup(ptyfd);
533: if (ptymaster < 0)
534: packet_disconnect("dup #2 failed: %.100s", strerror(errno));
535: s->ptymaster = ptymaster;
536:
537: /* Enter interactive session. */
1.47 markus 538: packet_set_interactive(1);
1.2 markus 539: if (compat20) {
540: session_set_fds(s, ptyfd, fdout, -1);
541: } else {
542: server_loop(pid, ptyfd, fdout, -1);
543: /* server_loop _has_ closed ptyfd and fdout. */
1.24 markus 544: }
545: }
546:
1.90 markus 547: /*
548: * This is called to fork and execute a command. If another command is
549: * to be forced, execute that instead.
550: */
551: void
552: do_exec(Session *s, const char *command)
553: {
1.210 dtucker 554: if (options.adm_forced_command) {
555: original_command = command;
556: command = options.adm_forced_command;
1.226 ! djm 557: if (strcmp(INTERNAL_SFTP_NAME, command) == 0)
! 558: s->is_subsystem = SUBSYSTEM_INT_SFTP;
! 559: else if (s->is_subsystem)
1.225 markus 560: s->is_subsystem = SUBSYSTEM_EXT;
1.210 dtucker 561: debug("Forced command (config) '%.900s'", command);
562: } else if (forced_command) {
1.90 markus 563: original_command = command;
564: command = forced_command;
1.226 ! djm 565: if (strcmp(INTERNAL_SFTP_NAME, command) == 0)
! 566: s->is_subsystem = SUBSYSTEM_INT_SFTP;
! 567: else if (s->is_subsystem)
1.225 markus 568: s->is_subsystem = SUBSYSTEM_EXT;
1.210 dtucker 569: debug("Forced command (key option) '%.900s'", command);
1.90 markus 570: }
1.163 markus 571:
572: #ifdef GSSAPI
573: if (options.gss_authentication) {
574: temporarily_use_uid(s->pw);
575: ssh_gssapi_storecreds();
576: restore_uid();
577: }
578: #endif
1.90 markus 579: if (s->ttyfd != -1)
580: do_exec_pty(s, command);
581: else
582: do_exec_no_pty(s, command);
583:
1.92 markus 584: original_command = NULL;
1.179 dtucker 585:
586: /*
587: * Clear loginmsg: it's the child's responsibility to display
588: * it to the user, otherwise multiple sessions may accumulate
589: * multiple copies of the login messages.
590: */
591: buffer_clear(&loginmsg);
1.90 markus 592: }
593:
594:
1.24 markus 595: /* administrative, login(1)-like work */
596: void
1.41 markus 597: do_login(Session *s, const char *command)
1.24 markus 598: {
599: socklen_t fromlen;
600: struct sockaddr_storage from;
601: struct passwd * pw = s->pw;
602: pid_t pid = getpid();
603:
604: /*
605: * Get IP address of client. If the connection is not a socket, let
606: * the address be 0.0.0.0.
607: */
608: memset(&from, 0, sizeof(from));
1.148 stevesk 609: fromlen = sizeof(from);
1.24 markus 610: if (packet_connection_is_on_socket()) {
611: if (getpeername(packet_get_connection_in(),
1.200 deraadt 612: (struct sockaddr *)&from, &fromlen) < 0) {
1.24 markus 613: debug("getpeername: %.100s", strerror(errno));
1.165 markus 614: cleanup_exit(255);
1.24 markus 615: }
616: }
1.25 markus 617:
1.24 markus 618: /* Record that there was a login on that tty from the remote host. */
1.133 markus 619: if (!use_privsep)
620: record_login(pid, s->tty, pw->pw_name, pw->pw_uid,
621: get_remote_name_or_ip(utmp_len,
1.158 markus 622: options.use_dns),
1.148 stevesk 623: (struct sockaddr *)&from, fromlen);
1.24 markus 624:
1.73 djm 625: if (check_quietlogin(s, command))
1.24 markus 626: return;
1.73 djm 627:
1.179 dtucker 628: display_loginmsg();
1.73 djm 629:
630: do_motd();
631: }
632:
633: /*
634: * Display the message of the day.
635: */
636: void
637: do_motd(void)
638: {
639: FILE *f;
640: char buf[256];
641:
1.24 markus 642: if (options.print_motd) {
1.28 millert 643: f = fopen(login_getcapstr(lc, "welcome", "/etc/motd",
644: "/etc/motd"), "r");
1.24 markus 645: if (f) {
646: while (fgets(buf, sizeof(buf), f))
647: fputs(buf, stdout);
648: fclose(f);
649: }
1.2 markus 650: }
1.73 djm 651: }
652:
653:
654: /*
655: * Check for quiet login, either .hushlogin or command given.
656: */
657: int
658: check_quietlogin(Session *s, const char *command)
659: {
660: char buf[256];
1.96 dugsong 661: struct passwd *pw = s->pw;
1.73 djm 662: struct stat st;
663:
664: /* Return 1 if .hushlogin exists or a command given. */
665: if (command != NULL)
666: return 1;
667: snprintf(buf, sizeof(buf), "%.200s/.hushlogin", pw->pw_dir);
668: if (login_getcapbool(lc, "hushlogin", 0) || stat(buf, &st) >= 0)
669: return 1;
670: return 0;
1.1 markus 671: }
672:
673: /*
674: * Sets the value of the given variable in the environment. If the variable
675: * already exists, its value is overriden.
676: */
1.161 markus 677: void
1.45 markus 678: child_set_env(char ***envp, u_int *envsizep, const char *name,
1.112 deraadt 679: const char *value)
1.1 markus 680: {
1.164 markus 681: char **env;
682: u_int envsize;
1.45 markus 683: u_int i, namelen;
1.1 markus 684:
685: /*
686: * Find the slot where the value should be stored. If the variable
687: * already exists, we reuse the slot; otherwise we append a new slot
688: * at the end of the array, expanding if necessary.
689: */
690: env = *envp;
691: namelen = strlen(name);
692: for (i = 0; env[i]; i++)
693: if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=')
694: break;
695: if (env[i]) {
696: /* Reuse the slot. */
697: xfree(env[i]);
698: } else {
699: /* New variable. Expand if necessary. */
1.164 markus 700: envsize = *envsizep;
701: if (i >= envsize - 1) {
702: if (envsize >= 1000)
703: fatal("child_set_env: too many env vars");
704: envsize += 50;
1.201 djm 705: env = (*envp) = xrealloc(env, envsize, sizeof(char *));
1.164 markus 706: *envsizep = envsize;
1.1 markus 707: }
708: /* Need to set the NULL pointer at end of array beyond the new slot. */
709: env[i + 1] = NULL;
710: }
711:
712: /* Allocate space and format the variable in the appropriate slot. */
713: env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1);
714: snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value);
715: }
716:
717: /*
718: * Reads environment variables from the given file and adds/overrides them
719: * into the environment. If the file does not exist, this does nothing.
720: * Otherwise, it must consist of empty lines, comments (line starts with '#')
721: * and assignments of the form name=value. No other forms are allowed.
722: */
1.94 itojun 723: static void
1.45 markus 724: read_environment_file(char ***env, u_int *envsize,
1.112 deraadt 725: const char *filename)
1.1 markus 726: {
727: FILE *f;
728: char buf[4096];
729: char *cp, *value;
1.142 deraadt 730: u_int lineno = 0;
1.1 markus 731:
732: f = fopen(filename, "r");
733: if (!f)
734: return;
735:
736: while (fgets(buf, sizeof(buf), f)) {
1.142 deraadt 737: if (++lineno > 1000)
738: fatal("Too many lines in environment file %s", filename);
1.1 markus 739: for (cp = buf; *cp == ' ' || *cp == '\t'; cp++)
740: ;
741: if (!*cp || *cp == '#' || *cp == '\n')
742: continue;
1.224 gilles 743:
744: cp[strcspn(cp, "\n")] = '\0';
745:
1.1 markus 746: value = strchr(cp, '=');
747: if (value == NULL) {
1.142 deraadt 748: fprintf(stderr, "Bad line %u in %.100s\n", lineno,
749: filename);
1.1 markus 750: continue;
751: }
1.14 deraadt 752: /*
753: * Replace the equals sign by nul, and advance value to
754: * the value string.
755: */
1.1 markus 756: *value = '\0';
757: value++;
758: child_set_env(env, envsize, cp, value);
759: }
760: fclose(f);
761: }
762:
1.127 markus 763: static char **
764: do_setup_env(Session *s, const char *shell)
1.1 markus 765: {
766: char buf[256];
1.127 markus 767: u_int i, envsize;
1.154 markus 768: char **env, *laddr;
1.127 markus 769: struct passwd *pw = s->pw;
1.1 markus 770:
771: /* Initialize the environment. */
772: envsize = 100;
1.220 djm 773: env = xcalloc(envsize, sizeof(char *));
1.1 markus 774: env[0] = NULL;
775:
1.161 markus 776: #ifdef GSSAPI
1.168 djm 777: /* Allow any GSSAPI methods that we've used to alter
1.161 markus 778: * the childs environment as they see fit
779: */
780: ssh_gssapi_do_child(&env, &envsize);
781: #endif
782:
1.1 markus 783: if (!options.use_login) {
784: /* Set basic environment. */
1.173 djm 785: for (i = 0; i < s->num_env; i++)
1.178 deraadt 786: child_set_env(&env, &envsize, s->env[i].name,
1.173 djm 787: s->env[i].val);
788:
1.1 markus 789: child_set_env(&env, &envsize, "USER", pw->pw_name);
790: child_set_env(&env, &envsize, "LOGNAME", pw->pw_name);
791: child_set_env(&env, &envsize, "HOME", pw->pw_dir);
1.145 markus 792: if (setusercontext(lc, pw, pw->pw_uid, LOGIN_SETPATH) < 0)
793: child_set_env(&env, &envsize, "PATH", _PATH_STDPATH);
794: else
795: child_set_env(&env, &envsize, "PATH", getenv("PATH"));
1.1 markus 796:
797: snprintf(buf, sizeof buf, "%.200s/%.50s",
798: _PATH_MAILDIR, pw->pw_name);
799: child_set_env(&env, &envsize, "MAIL", buf);
800:
801: /* Normal systems set SHELL by default. */
802: child_set_env(&env, &envsize, "SHELL", shell);
803: }
804: if (getenv("TZ"))
805: child_set_env(&env, &envsize, "TZ", getenv("TZ"));
806:
807: /* Set custom environment options from RSA authentication. */
1.110 markus 808: if (!options.use_login) {
809: while (custom_environment) {
810: struct envstring *ce = custom_environment;
1.143 deraadt 811: char *str = ce->s;
1.127 markus 812:
1.143 deraadt 813: for (i = 0; str[i] != '=' && str[i]; i++)
1.110 markus 814: ;
1.143 deraadt 815: if (str[i] == '=') {
816: str[i] = 0;
817: child_set_env(&env, &envsize, str, str + i + 1);
1.110 markus 818: }
819: custom_environment = ce->next;
820: xfree(ce->s);
821: xfree(ce);
1.1 markus 822: }
823: }
824:
1.149 stevesk 825: /* SSH_CLIENT deprecated */
1.1 markus 826: snprintf(buf, sizeof buf, "%.50s %d %d",
1.127 markus 827: get_remote_ipaddr(), get_remote_port(), get_local_port());
1.1 markus 828: child_set_env(&env, &envsize, "SSH_CLIENT", buf);
1.149 stevesk 829:
1.154 markus 830: laddr = get_local_ipaddr(packet_get_connection_in());
1.149 stevesk 831: snprintf(buf, sizeof buf, "%.50s %d %.50s %d",
1.154 markus 832: get_remote_ipaddr(), get_remote_port(), laddr, get_local_port());
833: xfree(laddr);
1.149 stevesk 834: child_set_env(&env, &envsize, "SSH_CONNECTION", buf);
1.1 markus 835:
1.60 markus 836: if (s->ttyfd != -1)
837: child_set_env(&env, &envsize, "SSH_TTY", s->tty);
838: if (s->term)
839: child_set_env(&env, &envsize, "TERM", s->term);
840: if (s->display)
841: child_set_env(&env, &envsize, "DISPLAY", s->display);
1.34 markus 842: if (original_command)
843: child_set_env(&env, &envsize, "SSH_ORIGINAL_COMMAND",
844: original_command);
1.96 dugsong 845: #ifdef KRB5
846: if (s->authctxt->krb5_ticket_file)
847: child_set_env(&env, &envsize, "KRB5CCNAME",
1.112 deraadt 848: s->authctxt->krb5_ticket_file);
1.96 dugsong 849: #endif
1.136 markus 850: if (auth_sock_name != NULL)
1.1 markus 851: child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME,
1.136 markus 852: auth_sock_name);
1.1 markus 853:
854: /* read $HOME/.ssh/environment. */
1.146 markus 855: if (options.permit_user_env && !options.use_login) {
1.14 deraadt 856: snprintf(buf, sizeof buf, "%.200s/.ssh/environment",
857: pw->pw_dir);
1.1 markus 858: read_environment_file(&env, &envsize, buf);
859: }
860: if (debug_flag) {
861: /* dump the environment */
862: fprintf(stderr, "Environment:\n");
863: for (i = 0; env[i]; i++)
864: fprintf(stderr, " %.200s\n", env[i]);
865: }
1.127 markus 866: return env;
867: }
868:
869: /*
870: * Run $HOME/.ssh/rc, /etc/ssh/sshrc, or xauth (whichever is found
871: * first in this order).
872: */
873: static void
874: do_rc_files(Session *s, const char *shell)
875: {
876: FILE *f = NULL;
877: char cmd[1024];
878: int do_xauth;
879: struct stat st;
880:
881: do_xauth =
882: s->display != NULL && s->auth_proto != NULL && s->auth_data != NULL;
883:
884: /* ignore _PATH_SSH_USER_RC for subsystems */
885: if (!s->is_subsystem && (stat(_PATH_SSH_USER_RC, &st) >= 0)) {
886: snprintf(cmd, sizeof cmd, "%s -c '%s %s'",
887: shell, _PATH_BSHELL, _PATH_SSH_USER_RC);
888: if (debug_flag)
889: fprintf(stderr, "Running %s\n", cmd);
890: f = popen(cmd, "w");
891: if (f) {
892: if (do_xauth)
893: fprintf(f, "%s %s\n", s->auth_proto,
894: s->auth_data);
895: pclose(f);
896: } else
897: fprintf(stderr, "Could not run %s\n",
898: _PATH_SSH_USER_RC);
899: } else if (stat(_PATH_SSH_SYSTEM_RC, &st) >= 0) {
900: if (debug_flag)
901: fprintf(stderr, "Running %s %s\n", _PATH_BSHELL,
902: _PATH_SSH_SYSTEM_RC);
903: f = popen(_PATH_BSHELL " " _PATH_SSH_SYSTEM_RC, "w");
904: if (f) {
905: if (do_xauth)
906: fprintf(f, "%s %s\n", s->auth_proto,
907: s->auth_data);
908: pclose(f);
909: } else
910: fprintf(stderr, "Could not run %s\n",
911: _PATH_SSH_SYSTEM_RC);
912: } else if (do_xauth && options.xauth_location != NULL) {
913: /* Add authority data to .Xauthority if appropriate. */
914: if (debug_flag) {
915: fprintf(stderr,
1.151 stevesk 916: "Running %.500s remove %.100s\n",
1.165 markus 917: options.xauth_location, s->auth_display);
1.151 stevesk 918: fprintf(stderr,
919: "%.500s add %.100s %.100s %.100s\n",
1.127 markus 920: options.xauth_location, s->auth_display,
921: s->auth_proto, s->auth_data);
922: }
923: snprintf(cmd, sizeof cmd, "%s -q -",
924: options.xauth_location);
925: f = popen(cmd, "w");
926: if (f) {
1.151 stevesk 927: fprintf(f, "remove %s\n",
928: s->auth_display);
1.127 markus 929: fprintf(f, "add %s %s %s\n",
930: s->auth_display, s->auth_proto,
931: s->auth_data);
932: pclose(f);
933: } else {
934: fprintf(stderr, "Could not run %s\n",
935: cmd);
936: }
937: }
938: }
939:
940: static void
941: do_nologin(struct passwd *pw)
942: {
943: FILE *f = NULL;
944: char buf[1024];
945:
946: if (!login_getcapbool(lc, "ignorenologin", 0) && pw->pw_uid)
947: f = fopen(login_getcapstr(lc, "nologin", _PATH_NOLOGIN,
948: _PATH_NOLOGIN), "r");
949: if (f) {
950: /* /etc/nologin exists. Print its contents and exit. */
1.155 itojun 951: logit("User %.100s not allowed because %s exists",
1.150 stevesk 952: pw->pw_name, _PATH_NOLOGIN);
1.127 markus 953: while (fgets(buf, sizeof(buf), f))
954: fputs(buf, stderr);
955: fclose(f);
956: exit(254);
957: }
958: }
959:
1.226 ! djm 960: /*
! 961: * Chroot into a directory after checking it for safety: all path components
! 962: * must be root-owned directories with strict permissions.
! 963: */
! 964: static void
! 965: safely_chroot(const char *path, uid_t uid)
! 966: {
! 967: const char *cp;
! 968: char component[MAXPATHLEN];
! 969: struct stat st;
! 970:
! 971: if (*path != '/')
! 972: fatal("chroot path does not begin at root");
! 973: if (strlen(path) >= sizeof(component))
! 974: fatal("chroot path too long");
! 975:
! 976: /*
! 977: * Descend the path, checking that each component is a
! 978: * root-owned directory with strict permissions.
! 979: */
! 980: for (cp = path; cp != NULL;) {
! 981: if ((cp = strchr(cp, '/')) == NULL)
! 982: strlcpy(component, path, sizeof(component));
! 983: else {
! 984: cp++;
! 985: memcpy(component, path, cp - path);
! 986: component[cp - path] = '\0';
! 987: }
! 988:
! 989: debug3("%s: checking '%s'", __func__, component);
! 990:
! 991: if (stat(component, &st) != 0)
! 992: fatal("%s: stat(\"%s\"): %s", __func__,
! 993: component, strerror(errno));
! 994: if (st.st_uid != 0 || (st.st_mode & 022) != 0)
! 995: fatal("bad ownership or modes for chroot "
! 996: "directory %s\"%s\"",
! 997: cp == NULL ? "" : "component ", component);
! 998: if (!S_ISDIR(st.st_mode))
! 999: fatal("chroot path %s\"%s\" is not a directory",
! 1000: cp == NULL ? "" : "component ", component);
! 1001:
! 1002: }
! 1003:
! 1004: if (chdir(path) == -1)
! 1005: fatal("Unable to chdir to chroot path \"%s\": "
! 1006: "%s", path, strerror(errno));
! 1007: if (chroot(path) == -1)
! 1008: fatal("chroot(\"%s\"): %s", path, strerror(errno));
! 1009: if (chdir("/") == -1)
! 1010: fatal("%s: chdir(/) after chroot: %s",
! 1011: __func__, strerror(errno));
! 1012: verbose("Changed root directory to \"%s\"", path);
! 1013: }
! 1014:
1.127 markus 1015: /* Set login name, uid, gid, and groups. */
1.130 provos 1016: void
1.127 markus 1017: do_setusercontext(struct passwd *pw)
1018: {
1019: if (getuid() == 0 || geteuid() == 0) {
1.226 ! djm 1020: /* Prepare groups */
1.127 markus 1021: if (setusercontext(lc, pw, pw->pw_uid,
1.226 ! djm 1022: (LOGIN_SETALL & ~(LOGIN_SETPATH|LOGIN_SETUSER))) < 0) {
1.127 markus 1023: perror("unable to set user context");
1024: exit(1);
1025: }
1.226 ! djm 1026:
! 1027: if (options.chroot_directory != NULL &&
! 1028: strcasecmp(options.chroot_directory, "none") != 0) {
! 1029: char *chroot_path;
! 1030:
! 1031: chroot_path = percent_expand(options.chroot_directory,
! 1032: "h", pw->pw_dir, "u", pw->pw_name, (char *)NULL);
! 1033: safely_chroot(chroot_path, pw->pw_uid);
! 1034: free(chroot_path);
! 1035: }
! 1036:
! 1037: /* Set UID */
! 1038: if (setusercontext(lc, pw, pw->pw_uid, LOGIN_SETUSER) < 0) {
! 1039: perror("unable to set user context (setuser)");
! 1040: exit(1);
! 1041: }
1.127 markus 1042: }
1043: if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid)
1044: fatal("Failed to set uids to %u.", (u_int) pw->pw_uid);
1045: }
1046:
1.131 markus 1047: static void
1.172 markus 1048: do_pwchange(Session *s)
1049: {
1.179 dtucker 1050: fflush(NULL);
1.172 markus 1051: fprintf(stderr, "WARNING: Your password has expired.\n");
1052: if (s->ttyfd != -1) {
1.178 deraadt 1053: fprintf(stderr,
1.172 markus 1054: "You must change your password now and login again!\n");
1055: execl(_PATH_PASSWD_PROG, "passwd", (char *)NULL);
1056: perror("passwd");
1057: } else {
1058: fprintf(stderr,
1059: "Password change required but no TTY available.\n");
1060: }
1061: exit(1);
1062: }
1063:
1064: static void
1.130 provos 1065: launch_login(struct passwd *pw, const char *hostname)
1066: {
1067: /* Launch login(1). */
1068:
1069: execl("/usr/bin/login", "login", "-h", hostname,
1070: "-p", "-f", "--", pw->pw_name, (char *)NULL);
1071:
1072: /* Login couldn't be executed, die. */
1073:
1074: perror("login");
1075: exit(1);
1076: }
1077:
1.172 markus 1078: static void
1079: child_close_fds(void)
1080: {
1081: int i;
1082:
1083: if (packet_get_connection_in() == packet_get_connection_out())
1084: close(packet_get_connection_in());
1085: else {
1086: close(packet_get_connection_in());
1087: close(packet_get_connection_out());
1088: }
1089: /*
1090: * Close all descriptors related to channels. They will still remain
1091: * open in the parent.
1092: */
1093: /* XXX better use close-on-exec? -markus */
1094: channel_close_all();
1095:
1096: /*
1097: * Close any extra file descriptors. Note that there may still be
1098: * descriptors left by system functions. They will be closed later.
1099: */
1100: endpwent();
1101:
1102: /*
1.188 djm 1103: * Close any extra open file descriptors so that we don't have them
1.172 markus 1104: * hanging around in clients. Note that we want to do this after
1105: * initgroups, because at least on Solaris 2.3 it leaves file
1106: * descriptors open.
1107: */
1108: for (i = 3; i < 64; i++)
1109: close(i);
1110: }
1111:
1.127 markus 1112: /*
1113: * Performs common processing for the child, such as setting up the
1114: * environment, closing extra file descriptors, setting the user and group
1115: * ids, and executing the command or shell.
1116: */
1.225 markus 1117: #define ARGV_MAX 10
1.127 markus 1118: void
1119: do_child(Session *s, const char *command)
1120: {
1121: extern char **environ;
1122: char **env;
1.225 markus 1123: char *argv[ARGV_MAX];
1.127 markus 1124: const char *shell, *shell0, *hostname = NULL;
1125: struct passwd *pw = s->pw;
1126:
1127: /* remove hostkey from the child's memory */
1128: destroy_sensitive_data();
1129:
1.172 markus 1130: /* Force a password change */
1131: if (s->authctxt->force_pwchange) {
1132: do_setusercontext(pw);
1133: child_close_fds();
1134: do_pwchange(s);
1135: exit(1);
1136: }
1137:
1.127 markus 1138: /* login(1) is only called if we execute the login shell */
1139: if (options.use_login && command != NULL)
1140: options.use_login = 0;
1141:
1142: /*
1143: * Login(1) does this as well, and it needs uid 0 for the "-h"
1144: * switch, so we let login(1) to this for us.
1145: */
1146: if (!options.use_login) {
1147: do_nologin(pw);
1148: do_setusercontext(pw);
1149: }
1150:
1151: /*
1152: * Get the shell from the password data. An empty shell field is
1153: * legal, and means /bin/sh.
1154: */
1155: shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
1.152 markus 1156:
1157: /*
1158: * Make sure $SHELL points to the shell from the password file,
1159: * even if shell is overridden from login.conf
1160: */
1161: env = do_setup_env(s, shell);
1162:
1.127 markus 1163: shell = login_getcapstr(lc, "shell", (char *)shell, (char *)shell);
1164:
1.26 millert 1165: /* we have to stash the hostname before we close our socket. */
1166: if (options.use_login)
1.70 stevesk 1167: hostname = get_remote_name_or_ip(utmp_len,
1.158 markus 1168: options.use_dns);
1.1 markus 1169: /*
1170: * Close the connection descriptors; note that this is the child, and
1171: * the server will still have the socket open, and it is important
1172: * that we do not shutdown it. Note that the descriptors cannot be
1173: * closed before building the environment, as we call
1174: * get_remote_ipaddr there.
1175: */
1.172 markus 1176: child_close_fds();
1.1 markus 1177:
1178: /*
1.125 deraadt 1179: * Must take new environment into use so that .ssh/rc,
1180: * /etc/ssh/sshrc and xauth are run in the proper environment.
1.1 markus 1181: */
1182: environ = env;
1.170 jakob 1183:
1184: #ifdef KRB5
1185: /*
1186: * At this point, we check to see if AFS is active and if we have
1187: * a valid Kerberos 5 TGT. If so, it seems like a good idea to see
1188: * if we can (and need to) extend the ticket into an AFS token. If
1189: * we don't do this, we run into potential problems if the user's
1190: * home directory is in AFS and it's not world-readable.
1191: */
1192:
1193: if (options.kerberos_get_afs_token && k_hasafs() &&
1.185 djm 1194: (s->authctxt->krb5_ctx != NULL)) {
1.170 jakob 1195: char cell[64];
1196:
1197: debug("Getting AFS token");
1198:
1199: k_setpag();
1200:
1201: if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0)
1202: krb5_afslog(s->authctxt->krb5_ctx,
1203: s->authctxt->krb5_fwd_ccache, cell, NULL);
1204:
1205: krb5_afslog_home(s->authctxt->krb5_ctx,
1206: s->authctxt->krb5_fwd_ccache, NULL, NULL, pw->pw_dir);
1207: }
1208: #endif
1.104 markus 1209:
1.188 djm 1210: /* Change current directory to the user's home directory. */
1.104 markus 1211: if (chdir(pw->pw_dir) < 0) {
1212: fprintf(stderr, "Could not chdir to home directory %s: %s\n",
1213: pw->pw_dir, strerror(errno));
1214: if (login_getcapbool(lc, "requirehome", 0))
1215: exit(1);
1216: }
1.1 markus 1217:
1.127 markus 1218: if (!options.use_login)
1219: do_rc_files(s, shell);
1.67 markus 1220:
1221: /* restore SIGPIPE for child */
1.217 stevesk 1222: signal(SIGPIPE, SIG_DFL);
1.67 markus 1223:
1.225 markus 1224: if (s->is_subsystem == SUBSYSTEM_INT_SFTP) {
1225: extern int optind, optreset;
1226: int i;
1227: char *p, *args;
1228:
1229: setproctitle("%s@internal-sftp-server", s->pw->pw_name);
1230: args = strdup(command ? command : "sftp-server");
1231: for (i = 0, (p = strtok(args, " ")); p; (p = strtok(NULL, " ")))
1232: if (i < ARGV_MAX - 1)
1233: argv[i++] = p;
1234: argv[i] = NULL;
1235: optind = optreset = 1;
1236: __progname = argv[0];
1.226 ! djm 1237: exit(sftp_server_main(i, argv, s->pw));
1.225 markus 1238: }
1239:
1.127 markus 1240: if (options.use_login) {
1.130 provos 1241: launch_login(pw, hostname);
1242: /* NEVERREACHED */
1.127 markus 1243: }
1244:
1245: /* Get the last component of the shell name. */
1246: if ((shell0 = strrchr(shell, '/')) != NULL)
1247: shell0++;
1248: else
1249: shell0 = shell;
1250:
1.1 markus 1251: /*
1252: * If we have no command, execute the shell. In this case, the shell
1253: * name to be passed in argv[0] is preceded by '-' to indicate that
1254: * this is a login shell.
1255: */
1256: if (!command) {
1.127 markus 1257: char argv0[256];
1.1 markus 1258:
1.127 markus 1259: /* Start the shell. Set initial character to '-'. */
1260: argv0[0] = '-';
1.1 markus 1261:
1.127 markus 1262: if (strlcpy(argv0 + 1, shell0, sizeof(argv0) - 1)
1.128 markus 1263: >= sizeof(argv0) - 1) {
1.127 markus 1264: errno = EINVAL;
1.1 markus 1265: perror(shell);
1266: exit(1);
1.127 markus 1267: }
1.1 markus 1268:
1.127 markus 1269: /* Execute the shell. */
1270: argv[0] = argv0;
1271: argv[1] = NULL;
1272: execve(shell, argv, env);
1273:
1274: /* Executing the shell failed. */
1275: perror(shell);
1276: exit(1);
1.1 markus 1277: }
1278: /*
1279: * Execute the command using the user's shell. This uses the -c
1280: * option to execute the command.
1281: */
1.127 markus 1282: argv[0] = (char *) shell0;
1.1 markus 1283: argv[1] = "-c";
1284: argv[2] = (char *) command;
1285: argv[3] = NULL;
1286: execve(shell, argv, env);
1287: perror(shell);
1288: exit(1);
1289: }
1290:
1291: Session *
1292: session_new(void)
1293: {
1294: int i;
1295: static int did_init = 0;
1296: if (!did_init) {
1297: debug("session_new: init");
1.112 deraadt 1298: for (i = 0; i < MAX_SESSIONS; i++) {
1.1 markus 1299: sessions[i].used = 0;
1300: }
1301: did_init = 1;
1302: }
1.112 deraadt 1303: for (i = 0; i < MAX_SESSIONS; i++) {
1.1 markus 1304: Session *s = &sessions[i];
1305: if (! s->used) {
1.68 djm 1306: memset(s, 0, sizeof(*s));
1.1 markus 1307: s->chanid = -1;
1308: s->ptyfd = -1;
1309: s->ttyfd = -1;
1310: s->used = 1;
1.85 markus 1311: s->self = i;
1.184 djm 1312: s->x11_chanids = NULL;
1.1 markus 1313: debug("session_new: session %d", i);
1314: return s;
1315: }
1316: }
1317: return NULL;
1318: }
1319:
1.94 itojun 1320: static void
1.1 markus 1321: session_dump(void)
1322: {
1323: int i;
1.112 deraadt 1324: for (i = 0; i < MAX_SESSIONS; i++) {
1.1 markus 1325: Session *s = &sessions[i];
1.137 mpech 1326: debug("dump: used %d session %d %p channel %d pid %ld",
1.1 markus 1327: s->used,
1328: s->self,
1329: s,
1330: s->chanid,
1.137 mpech 1331: (long)s->pid);
1.1 markus 1332: }
1333: }
1334:
1.2 markus 1335: int
1.97 markus 1336: session_open(Authctxt *authctxt, int chanid)
1.2 markus 1337: {
1338: Session *s = session_new();
1339: debug("session_open: channel %d", chanid);
1340: if (s == NULL) {
1341: error("no more sessions");
1342: return 0;
1343: }
1.97 markus 1344: s->authctxt = authctxt;
1345: s->pw = authctxt->pw;
1.167 djm 1346: if (s->pw == NULL || !authctxt->valid)
1.54 stevesk 1347: fatal("no user for session %d", s->self);
1.2 markus 1348: debug("session_open: session %d: link with channel %d", s->self, chanid);
1349: s->chanid = chanid;
1350: return 1;
1351: }
1352:
1.130 provos 1353: Session *
1354: session_by_tty(char *tty)
1355: {
1356: int i;
1357: for (i = 0; i < MAX_SESSIONS; i++) {
1358: Session *s = &sessions[i];
1359: if (s->used && s->ttyfd != -1 && strcmp(s->tty, tty) == 0) {
1360: debug("session_by_tty: session %d tty %s", i, tty);
1361: return s;
1362: }
1363: }
1364: debug("session_by_tty: unknown tty %.100s", tty);
1365: session_dump();
1366: return NULL;
1367: }
1368:
1.94 itojun 1369: static Session *
1.2 markus 1370: session_by_channel(int id)
1371: {
1372: int i;
1.112 deraadt 1373: for (i = 0; i < MAX_SESSIONS; i++) {
1.2 markus 1374: Session *s = &sessions[i];
1375: if (s->used && s->chanid == id) {
1376: debug("session_by_channel: session %d channel %d", i, id);
1377: return s;
1378: }
1379: }
1380: debug("session_by_channel: unknown channel %d", id);
1381: session_dump();
1382: return NULL;
1383: }
1384:
1.94 itojun 1385: static Session *
1.184 djm 1386: session_by_x11_channel(int id)
1387: {
1388: int i, j;
1389:
1390: for (i = 0; i < MAX_SESSIONS; i++) {
1391: Session *s = &sessions[i];
1392:
1393: if (s->x11_chanids == NULL || !s->used)
1394: continue;
1395: for (j = 0; s->x11_chanids[j] != -1; j++) {
1396: if (s->x11_chanids[j] == id) {
1397: debug("session_by_x11_channel: session %d "
1398: "channel %d", s->self, id);
1399: return s;
1400: }
1401: }
1402: }
1403: debug("session_by_x11_channel: unknown channel %d", id);
1404: session_dump();
1405: return NULL;
1406: }
1407:
1408: static Session *
1.2 markus 1409: session_by_pid(pid_t pid)
1410: {
1411: int i;
1.137 mpech 1412: debug("session_by_pid: pid %ld", (long)pid);
1.112 deraadt 1413: for (i = 0; i < MAX_SESSIONS; i++) {
1.2 markus 1414: Session *s = &sessions[i];
1415: if (s->used && s->pid == pid)
1416: return s;
1417: }
1.137 mpech 1418: error("session_by_pid: unknown pid %ld", (long)pid);
1.2 markus 1419: session_dump();
1420: return NULL;
1421: }
1422:
1.94 itojun 1423: static int
1.2 markus 1424: session_window_change_req(Session *s)
1425: {
1426: s->col = packet_get_int();
1427: s->row = packet_get_int();
1428: s->xpixel = packet_get_int();
1429: s->ypixel = packet_get_int();
1.116 markus 1430: packet_check_eom();
1.2 markus 1431: pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1432: return 1;
1433: }
1434:
1.94 itojun 1435: static int
1.2 markus 1436: session_pty_req(Session *s)
1437: {
1.45 markus 1438: u_int len;
1.72 stevesk 1439: int n_bytes;
1.132 markus 1440:
1.86 markus 1441: if (no_pty_flag) {
1442: debug("Allocating a pty not permitted for this authentication.");
1.19 markus 1443: return 0;
1.86 markus 1444: }
1445: if (s->ttyfd != -1) {
1446: packet_disconnect("Protocol error: you already have a pty.");
1.3 markus 1447: return 0;
1.86 markus 1448: }
1449:
1.2 markus 1450: s->term = packet_get_string(&len);
1.86 markus 1451:
1452: if (compat20) {
1453: s->col = packet_get_int();
1454: s->row = packet_get_int();
1455: } else {
1456: s->row = packet_get_int();
1457: s->col = packet_get_int();
1458: }
1.2 markus 1459: s->xpixel = packet_get_int();
1460: s->ypixel = packet_get_int();
1461:
1462: if (strcmp(s->term, "") == 0) {
1463: xfree(s->term);
1464: s->term = NULL;
1465: }
1.86 markus 1466:
1.2 markus 1467: /* Allocate a pty and open it. */
1.86 markus 1468: debug("Allocating pty.");
1.130 provos 1469: if (!PRIVSEP(pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty)))) {
1.86 markus 1470: if (s->term)
1471: xfree(s->term);
1.2 markus 1472: s->term = NULL;
1473: s->ptyfd = -1;
1474: s->ttyfd = -1;
1475: error("session_pty_req: session %d alloc failed", s->self);
1.3 markus 1476: return 0;
1.2 markus 1477: }
1478: debug("session_pty_req: session %d alloc %s", s->self, s->tty);
1.86 markus 1479:
1480: /* for SSH1 the tty modes length is not given */
1481: if (!compat20)
1482: n_bytes = packet_remaining();
1483: tty_parse_modes(s->ttyfd, &n_bytes);
1484:
1.130 provos 1485: if (!use_privsep)
1486: pty_setowner(s->pw, s->tty);
1.86 markus 1487:
1488: /* Set window size from the packet. */
1.2 markus 1489: pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1490:
1.116 markus 1491: packet_check_eom();
1.9 markus 1492: session_proctitle(s);
1.2 markus 1493: return 1;
1494: }
1495:
1.94 itojun 1496: static int
1.7 markus 1497: session_subsystem_req(Session *s)
1498: {
1.105 markus 1499: struct stat st;
1.45 markus 1500: u_int len;
1.7 markus 1501: int success = 0;
1.205 djm 1502: char *prog, *cmd, *subsys = packet_get_string(&len);
1.182 djm 1503: u_int i;
1.7 markus 1504:
1.116 markus 1505: packet_check_eom();
1.155 itojun 1506: logit("subsystem request for %.100s", subsys);
1.18 jakob 1507:
1508: for (i = 0; i < options.num_subsystems; i++) {
1.105 markus 1509: if (strcmp(subsys, options.subsystem_name[i]) == 0) {
1.205 djm 1510: prog = options.subsystem_command[i];
1511: cmd = options.subsystem_args[i];
1.226 ! djm 1512: if (!strcmp(INTERNAL_SFTP_NAME, prog)) {
1.225 markus 1513: s->is_subsystem = SUBSYSTEM_INT_SFTP;
1514: } else if (stat(prog, &st) < 0) {
1.205 djm 1515: error("subsystem: cannot stat %s: %s", prog,
1.105 markus 1516: strerror(errno));
1517: break;
1.225 markus 1518: } else {
1519: s->is_subsystem = SUBSYSTEM_EXT;
1.105 markus 1520: }
1521: debug("subsystem: exec() %s", cmd);
1522: do_exec(s, cmd);
1.18 jakob 1523: success = 1;
1.122 markus 1524: break;
1.18 jakob 1525: }
1526: }
1527:
1528: if (!success)
1.155 itojun 1529: logit("subsystem request for %.100s failed, subsystem not found",
1.105 markus 1530: subsys);
1.7 markus 1531:
1532: xfree(subsys);
1533: return success;
1534: }
1535:
1.94 itojun 1536: static int
1.7 markus 1537: session_x11_req(Session *s)
1538: {
1.81 markus 1539: int success;
1.7 markus 1540:
1.184 djm 1541: if (s->auth_proto != NULL || s->auth_data != NULL) {
1542: error("session_x11_req: session %d: "
1.190 stevesk 1543: "x11 forwarding already active", s->self);
1.184 djm 1544: return 0;
1545: }
1.7 markus 1546: s->single_connection = packet_get_char();
1547: s->auth_proto = packet_get_string(NULL);
1548: s->auth_data = packet_get_string(NULL);
1549: s->screen = packet_get_int();
1.116 markus 1550: packet_check_eom();
1.7 markus 1551:
1.81 markus 1552: success = session_setup_x11fwd(s);
1553: if (!success) {
1.7 markus 1554: xfree(s->auth_proto);
1555: xfree(s->auth_data);
1.84 markus 1556: s->auth_proto = NULL;
1557: s->auth_data = NULL;
1.7 markus 1558: }
1.81 markus 1559: return success;
1.7 markus 1560: }
1561:
1.94 itojun 1562: static int
1.19 markus 1563: session_shell_req(Session *s)
1564: {
1.116 markus 1565: packet_check_eom();
1.90 markus 1566: do_exec(s, NULL);
1.19 markus 1567: return 1;
1568: }
1569:
1.94 itojun 1570: static int
1.19 markus 1571: session_exec_req(Session *s)
1572: {
1.45 markus 1573: u_int len;
1.19 markus 1574: char *command = packet_get_string(&len);
1.116 markus 1575: packet_check_eom();
1.90 markus 1576: do_exec(s, command);
1.92 markus 1577: xfree(command);
1.19 markus 1578: return 1;
1579: }
1580:
1.94 itojun 1581: static int
1.157 markus 1582: session_break_req(Session *s)
1583: {
1584:
1.175 deraadt 1585: packet_get_int(); /* ignored */
1.157 markus 1586: packet_check_eom();
1587:
1.160 markus 1588: if (s->ttyfd == -1 ||
1589: tcsendbreak(s->ttyfd, 0) < 0)
1.157 markus 1590: return 0;
1591: return 1;
1592: }
1593:
1594: static int
1.173 djm 1595: session_env_req(Session *s)
1596: {
1597: char *name, *val;
1598: u_int name_len, val_len, i;
1599:
1600: name = packet_get_string(&name_len);
1601: val = packet_get_string(&val_len);
1602: packet_check_eom();
1603:
1604: /* Don't set too many environment variables */
1605: if (s->num_env > 128) {
1606: debug2("Ignoring env request %s: too many env vars", name);
1607: goto fail;
1608: }
1609:
1610: for (i = 0; i < options.num_accept_env; i++) {
1611: if (match_pattern(name, options.accept_env[i])) {
1612: debug2("Setting env %d: %s=%s", s->num_env, name, val);
1.201 djm 1613: s->env = xrealloc(s->env, s->num_env + 1,
1614: sizeof(*s->env));
1.173 djm 1615: s->env[s->num_env].name = name;
1616: s->env[s->num_env].val = val;
1617: s->num_env++;
1618: return (1);
1619: }
1620: }
1621: debug2("Ignoring env request %s: disallowed name", name);
1622:
1623: fail:
1624: xfree(name);
1625: xfree(val);
1626: return (0);
1627: }
1628:
1629: static int
1.43 markus 1630: session_auth_agent_req(Session *s)
1631: {
1632: static int called = 0;
1.116 markus 1633: packet_check_eom();
1.44 markus 1634: if (no_agent_forwarding_flag) {
1635: debug("session_auth_agent_req: no_agent_forwarding_flag");
1636: return 0;
1637: }
1.43 markus 1638: if (called) {
1639: return 0;
1640: } else {
1641: called = 1;
1642: return auth_input_request_forwarding(s->pw);
1643: }
1644: }
1645:
1.123 markus 1646: int
1647: session_input_channel_req(Channel *c, const char *rtype)
1.2 markus 1648: {
1649: int success = 0;
1650: Session *s;
1651:
1.123 markus 1652: if ((s = session_by_channel(c->self)) == NULL) {
1.155 itojun 1653: logit("session_input_channel_req: no session %d req %.100s",
1.123 markus 1654: c->self, rtype);
1655: return 0;
1656: }
1657: debug("session_input_channel_req: session %d req %s", s->self, rtype);
1.2 markus 1658:
1659: /*
1.64 markus 1660: * a session is in LARVAL state until a shell, a command
1661: * or a subsystem is executed
1.2 markus 1662: */
1663: if (c->type == SSH_CHANNEL_LARVAL) {
1664: if (strcmp(rtype, "shell") == 0) {
1.19 markus 1665: success = session_shell_req(s);
1.2 markus 1666: } else if (strcmp(rtype, "exec") == 0) {
1.19 markus 1667: success = session_exec_req(s);
1.2 markus 1668: } else if (strcmp(rtype, "pty-req") == 0) {
1.221 stevesk 1669: success = session_pty_req(s);
1.7 markus 1670: } else if (strcmp(rtype, "x11-req") == 0) {
1671: success = session_x11_req(s);
1.43 markus 1672: } else if (strcmp(rtype, "auth-agent-req@openssh.com") == 0) {
1673: success = session_auth_agent_req(s);
1.7 markus 1674: } else if (strcmp(rtype, "subsystem") == 0) {
1675: success = session_subsystem_req(s);
1.173 djm 1676: } else if (strcmp(rtype, "env") == 0) {
1677: success = session_env_req(s);
1.2 markus 1678: }
1679: }
1680: if (strcmp(rtype, "window-change") == 0) {
1681: success = session_window_change_req(s);
1.177 djm 1682: } else if (strcmp(rtype, "break") == 0) {
1683: success = session_break_req(s);
1.2 markus 1684: }
1.177 djm 1685:
1.123 markus 1686: return success;
1.2 markus 1687: }
1688:
1689: void
1690: session_set_fds(Session *s, int fdin, int fdout, int fderr)
1691: {
1692: if (!compat20)
1693: fatal("session_set_fds: called for proto != 2.0");
1694: /*
1695: * now that have a child and a pipe to the child,
1696: * we can activate our channel and register the fd's
1697: */
1698: if (s->chanid == -1)
1699: fatal("no channel for session %d", s->self);
1700: channel_set_fds(s->chanid,
1701: fdout, fdin, fderr,
1.42 markus 1702: fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ,
1.126 markus 1703: 1,
1704: CHAN_SES_WINDOW_DEFAULT);
1.2 markus 1705: }
1706:
1.85 markus 1707: /*
1708: * Function to perform pty cleanup. Also called if we get aborted abnormally
1709: * (e.g., due to a dropped connection).
1710: */
1.130 provos 1711: void
1.165 markus 1712: session_pty_cleanup2(Session *s)
1.1 markus 1713: {
1.85 markus 1714: if (s == NULL) {
1715: error("session_pty_cleanup: no session");
1716: return;
1717: }
1718: if (s->ttyfd == -1)
1.1 markus 1719: return;
1720:
1.54 stevesk 1721: debug("session_pty_cleanup: session %d release %s", s->self, s->tty);
1.1 markus 1722:
1723: /* Record that the user has logged out. */
1.85 markus 1724: if (s->pid != 0)
1725: record_logout(s->pid, s->tty);
1.1 markus 1726:
1727: /* Release the pseudo-tty. */
1.130 provos 1728: if (getuid() == 0)
1729: pty_release(s->tty);
1.1 markus 1730:
1731: /*
1732: * Close the server side of the socket pairs. We must do this after
1733: * the pty cleanup, so that another process doesn't get this pty
1734: * while we're still cleaning up.
1735: */
1736: if (close(s->ptymaster) < 0)
1.130 provos 1737: error("close(s->ptymaster/%d): %s", s->ptymaster, strerror(errno));
1.108 markus 1738:
1739: /* unlink pty from session */
1740: s->ttyfd = -1;
1.2 markus 1741: }
1742:
1.130 provos 1743: void
1.165 markus 1744: session_pty_cleanup(Session *s)
1.130 provos 1745: {
1.165 markus 1746: PRIVSEP(session_pty_cleanup2(s));
1.130 provos 1747: }
1748:
1.147 markus 1749: static char *
1750: sig2name(int sig)
1751: {
1752: #define SSH_SIG(x) if (sig == SIG ## x) return #x
1753: SSH_SIG(ABRT);
1754: SSH_SIG(ALRM);
1755: SSH_SIG(FPE);
1756: SSH_SIG(HUP);
1757: SSH_SIG(ILL);
1758: SSH_SIG(INT);
1759: SSH_SIG(KILL);
1760: SSH_SIG(PIPE);
1761: SSH_SIG(QUIT);
1762: SSH_SIG(SEGV);
1763: SSH_SIG(TERM);
1764: SSH_SIG(USR1);
1765: SSH_SIG(USR2);
1766: #undef SSH_SIG
1767: return "SIG@openssh.com";
1768: }
1769:
1.94 itojun 1770: static void
1.184 djm 1771: session_close_x11(int id)
1772: {
1773: Channel *c;
1774:
1.189 markus 1775: if ((c = channel_by_id(id)) == NULL) {
1.184 djm 1776: debug("session_close_x11: x11 channel %d missing", id);
1777: } else {
1778: /* Detach X11 listener */
1779: debug("session_close_x11: detach x11 channel %d", id);
1780: channel_cancel_cleanup(id);
1781: if (c->ostate != CHAN_OUTPUT_CLOSED)
1782: chan_mark_dead(c);
1783: }
1784: }
1785:
1786: static void
1787: session_close_single_x11(int id, void *arg)
1788: {
1789: Session *s;
1790: u_int i;
1791:
1792: debug3("session_close_single_x11: channel %d", id);
1793: channel_cancel_cleanup(id);
1.221 stevesk 1794: if ((s = session_by_x11_channel(id)) == NULL)
1.184 djm 1795: fatal("session_close_single_x11: no x11 channel %d", id);
1796: for (i = 0; s->x11_chanids[i] != -1; i++) {
1797: debug("session_close_single_x11: session %d: "
1798: "closing channel %d", s->self, s->x11_chanids[i]);
1799: /*
1800: * The channel "id" is already closing, but make sure we
1801: * close all of its siblings.
1802: */
1803: if (s->x11_chanids[i] != id)
1804: session_close_x11(s->x11_chanids[i]);
1805: }
1806: xfree(s->x11_chanids);
1807: s->x11_chanids = NULL;
1808: if (s->display) {
1809: xfree(s->display);
1810: s->display = NULL;
1811: }
1812: if (s->auth_proto) {
1813: xfree(s->auth_proto);
1814: s->auth_proto = NULL;
1815: }
1816: if (s->auth_data) {
1817: xfree(s->auth_data);
1818: s->auth_data = NULL;
1819: }
1820: if (s->auth_display) {
1821: xfree(s->auth_display);
1822: s->auth_display = NULL;
1823: }
1824: }
1825:
1826: static void
1.2 markus 1827: session_exit_message(Session *s, int status)
1828: {
1829: Channel *c;
1.124 markus 1830:
1831: if ((c = channel_lookup(s->chanid)) == NULL)
1.85 markus 1832: fatal("session_exit_message: session %d: no channel %d",
1.2 markus 1833: s->self, s->chanid);
1.137 mpech 1834: debug("session_exit_message: session %d channel %d pid %ld",
1835: s->self, s->chanid, (long)s->pid);
1.2 markus 1836:
1837: if (WIFEXITED(status)) {
1.124 markus 1838: channel_request_start(s->chanid, "exit-status", 0);
1.2 markus 1839: packet_put_int(WEXITSTATUS(status));
1840: packet_send();
1841: } else if (WIFSIGNALED(status)) {
1.124 markus 1842: channel_request_start(s->chanid, "exit-signal", 0);
1.147 markus 1843: packet_put_cstring(sig2name(WTERMSIG(status)));
1.2 markus 1844: packet_put_char(WCOREDUMP(status));
1845: packet_put_cstring("");
1846: packet_put_cstring("");
1847: packet_send();
1848: } else {
1849: /* Some weird exit cause. Just exit. */
1850: packet_disconnect("wait returned status %04x.", status);
1851: }
1852:
1853: /* disconnect channel */
1854: debug("session_exit_message: release channel %d", s->chanid);
1.187 djm 1855:
1856: /*
1857: * Adjust cleanup callback attachment to send close messages when
1.199 deraadt 1858: * the channel gets EOF. The session will be then be closed
1.187 djm 1859: * by session_close_by_channel when the childs close their fds.
1860: */
1861: channel_register_cleanup(c->self, session_close_by_channel, 1);
1862:
1.5 markus 1863: /*
1864: * emulate a write failure with 'chan_write_failed', nobody will be
1865: * interested in data we write.
1866: * Note that we must not call 'chan_read_failed', since there could
1867: * be some more data waiting in the pipe.
1868: */
1.8 markus 1869: if (c->ostate != CHAN_OUTPUT_CLOSED)
1870: chan_write_failed(c);
1.2 markus 1871: }
1872:
1.130 provos 1873: void
1.85 markus 1874: session_close(Session *s)
1.2 markus 1875: {
1.182 djm 1876: u_int i;
1.173 djm 1877:
1.137 mpech 1878: debug("session_close: session %d pid %ld", s->self, (long)s->pid);
1.165 markus 1879: if (s->ttyfd != -1)
1.85 markus 1880: session_pty_cleanup(s);
1.2 markus 1881: if (s->term)
1882: xfree(s->term);
1883: if (s->display)
1884: xfree(s->display);
1.184 djm 1885: if (s->x11_chanids)
1886: xfree(s->x11_chanids);
1.118 stevesk 1887: if (s->auth_display)
1888: xfree(s->auth_display);
1.2 markus 1889: if (s->auth_data)
1890: xfree(s->auth_data);
1891: if (s->auth_proto)
1892: xfree(s->auth_proto);
1893: s->used = 0;
1.219 djm 1894: if (s->env != NULL) {
1895: for (i = 0; i < s->num_env; i++) {
1896: xfree(s->env[i].name);
1897: xfree(s->env[i].val);
1898: }
1899: xfree(s->env);
1.173 djm 1900: }
1.9 markus 1901: session_proctitle(s);
1.2 markus 1902: }
1903:
1904: void
1905: session_close_by_pid(pid_t pid, int status)
1906: {
1907: Session *s = session_by_pid(pid);
1908: if (s == NULL) {
1.137 mpech 1909: debug("session_close_by_pid: no session for pid %ld",
1910: (long)pid);
1.2 markus 1911: return;
1912: }
1913: if (s->chanid != -1)
1914: session_exit_message(s, status);
1.187 djm 1915: if (s->ttyfd != -1)
1916: session_pty_cleanup(s);
1.197 djm 1917: s->pid = 0;
1.98 markus 1918: }
1919:
1.2 markus 1920: /*
1921: * this is called when a channel dies before
1922: * the session 'child' itself dies
1923: */
1924: void
1925: session_close_by_channel(int id, void *arg)
1926: {
1927: Session *s = session_by_channel(id);
1.187 djm 1928: u_int i;
1.184 djm 1929:
1.2 markus 1930: if (s == NULL) {
1.107 markus 1931: debug("session_close_by_channel: no session for id %d", id);
1.2 markus 1932: return;
1933: }
1.137 mpech 1934: debug("session_close_by_channel: channel %d child %ld",
1935: id, (long)s->pid);
1.107 markus 1936: if (s->pid != 0) {
1937: debug("session_close_by_channel: channel %d: has child", id);
1.108 markus 1938: /*
1939: * delay detach of session, but release pty, since
1940: * the fd's to the child are already closed
1941: */
1.165 markus 1942: if (s->ttyfd != -1)
1.108 markus 1943: session_pty_cleanup(s);
1.107 markus 1944: return;
1945: }
1946: /* detach by removing callback */
1.2 markus 1947: channel_cancel_cleanup(s->chanid);
1.187 djm 1948:
1949: /* Close any X11 listeners associated with this session */
1950: if (s->x11_chanids != NULL) {
1951: for (i = 0; s->x11_chanids[i] != -1; i++) {
1952: session_close_x11(s->x11_chanids[i]);
1953: s->x11_chanids[i] = -1;
1954: }
1955: }
1956:
1.2 markus 1957: s->chanid = -1;
1.106 markus 1958: session_close(s);
1959: }
1960:
1961: void
1.130 provos 1962: session_destroy_all(void (*closefunc)(Session *))
1.106 markus 1963: {
1964: int i;
1.112 deraadt 1965: for (i = 0; i < MAX_SESSIONS; i++) {
1.106 markus 1966: Session *s = &sessions[i];
1.130 provos 1967: if (s->used) {
1968: if (closefunc != NULL)
1969: closefunc(s);
1970: else
1971: session_close(s);
1972: }
1.2 markus 1973: }
1.9 markus 1974: }
1975:
1.94 itojun 1976: static char *
1.9 markus 1977: session_tty_list(void)
1978: {
1979: static char buf[1024];
1980: int i;
1981: buf[0] = '\0';
1.112 deraadt 1982: for (i = 0; i < MAX_SESSIONS; i++) {
1.9 markus 1983: Session *s = &sessions[i];
1984: if (s->used && s->ttyfd != -1) {
1985: if (buf[0] != '\0')
1986: strlcat(buf, ",", sizeof buf);
1987: strlcat(buf, strrchr(s->tty, '/') + 1, sizeof buf);
1988: }
1989: }
1990: if (buf[0] == '\0')
1991: strlcpy(buf, "notty", sizeof buf);
1992: return buf;
1993: }
1994:
1995: void
1996: session_proctitle(Session *s)
1997: {
1998: if (s->pw == NULL)
1999: error("no user for session %d", s->self);
2000: else
2001: setproctitle("%s@%s", s->pw->pw_name, session_tty_list());
1.81 markus 2002: }
2003:
2004: int
2005: session_setup_x11fwd(Session *s)
2006: {
2007: struct stat st;
1.109 stevesk 2008: char display[512], auth_display[512];
2009: char hostname[MAXHOSTNAMELEN];
1.184 djm 2010: u_int i;
1.81 markus 2011:
2012: if (no_x11_forwarding_flag) {
2013: packet_send_debug("X11 forwarding disabled in user configuration file.");
2014: return 0;
2015: }
2016: if (!options.x11_forwarding) {
2017: debug("X11 forwarding disabled in server configuration file.");
2018: return 0;
2019: }
2020: if (!options.xauth_location ||
2021: (stat(options.xauth_location, &st) == -1)) {
2022: packet_send_debug("No xauth program; cannot forward with spoofing.");
1.91 markus 2023: return 0;
2024: }
2025: if (options.use_login) {
2026: packet_send_debug("X11 forwarding disabled; "
2027: "not compatible with UseLogin=yes.");
1.81 markus 2028: return 0;
2029: }
1.87 markus 2030: if (s->display != NULL) {
1.81 markus 2031: debug("X11 display already set.");
2032: return 0;
2033: }
1.140 deraadt 2034: if (x11_create_display_inet(options.x11_display_offset,
2035: options.x11_use_localhost, s->single_connection,
1.184 djm 2036: &s->display_number, &s->x11_chanids) == -1) {
1.87 markus 2037: debug("x11_create_display_inet failed.");
1.81 markus 2038: return 0;
1.184 djm 2039: }
2040: for (i = 0; s->x11_chanids[i] != -1; i++) {
2041: channel_register_cleanup(s->x11_chanids[i],
1.187 djm 2042: session_close_single_x11, 0);
1.81 markus 2043: }
1.109 stevesk 2044:
2045: /* Set up a suitable value for the DISPLAY variable. */
2046: if (gethostname(hostname, sizeof(hostname)) < 0)
2047: fatal("gethostname: %.100s", strerror(errno));
2048: /*
2049: * auth_display must be used as the displayname when the
2050: * authorization entry is added with xauth(1). This will be
2051: * different than the DISPLAY string for localhost displays.
2052: */
1.119 stevesk 2053: if (options.x11_use_localhost) {
1.140 deraadt 2054: snprintf(display, sizeof display, "localhost:%u.%u",
1.109 stevesk 2055: s->display_number, s->screen);
1.140 deraadt 2056: snprintf(auth_display, sizeof auth_display, "unix:%u.%u",
1.118 stevesk 2057: s->display_number, s->screen);
1.109 stevesk 2058: s->display = xstrdup(display);
1.118 stevesk 2059: s->auth_display = xstrdup(auth_display);
1.109 stevesk 2060: } else {
1.140 deraadt 2061: snprintf(display, sizeof display, "%.400s:%u.%u", hostname,
1.109 stevesk 2062: s->display_number, s->screen);
2063: s->display = xstrdup(display);
1.118 stevesk 2064: s->auth_display = xstrdup(display);
1.109 stevesk 2065: }
2066:
1.81 markus 2067: return 1;
1.2 markus 2068: }
2069:
1.94 itojun 2070: static void
1.49 markus 2071: do_authenticated2(Authctxt *authctxt)
1.2 markus 2072: {
1.97 markus 2073: server_loop2(authctxt);
1.165 markus 2074: }
2075:
2076: void
2077: do_cleanup(Authctxt *authctxt)
2078: {
2079: static int called = 0;
2080:
2081: debug("do_cleanup");
2082:
2083: /* no cleanup if we're in the child for login shell */
2084: if (is_child)
2085: return;
2086:
2087: /* avoid double cleanup */
2088: if (called)
2089: return;
2090: called = 1;
2091:
1.218 markus 2092: if (authctxt == NULL || !authctxt->authenticated)
1.165 markus 2093: return;
2094: #ifdef KRB5
2095: if (options.kerberos_ticket_cleanup &&
2096: authctxt->krb5_ctx)
2097: krb5_cleanup_proc(authctxt);
1.161 markus 2098: #endif
1.165 markus 2099:
2100: #ifdef GSSAPI
2101: if (compat20 && options.gss_cleanup_creds)
2102: ssh_gssapi_cleanup_creds();
2103: #endif
2104:
2105: /* remove agent socket */
2106: auth_sock_cleanup_proc(authctxt->pw);
2107:
2108: /*
2109: * Cleanup ptys/utmp only if privsep is disabled,
2110: * or if running in monitor.
2111: */
2112: if (!use_privsep || mm_is_monitor())
2113: session_destroy_all(session_pty_cleanup2);
1.1 markus 2114: }
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