Annotation of src/usr.bin/ssh/session.c, Revision 1.291
1.291 ! djm 1: /* $OpenBSD: session.c,v 1.290 2017/06/24 06:34:38 djm 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>
1.236 djm 41: #include <sys/queue.h>
1.192 stevesk 42:
1.282 djm 43: #include <ctype.h>
1.209 stevesk 44: #include <errno.h>
1.253 djm 45: #include <fcntl.h>
1.204 stevesk 46: #include <grp.h>
1.223 djm 47: #include <login_cap.h>
1.272 djm 48: #include <netdb.h>
1.192 stevesk 49: #include <paths.h>
1.206 stevesk 50: #include <pwd.h>
1.195 stevesk 51: #include <signal.h>
1.215 stevesk 52: #include <stdio.h>
1.214 stevesk 53: #include <stdlib.h>
1.212 stevesk 54: #include <string.h>
1.211 stevesk 55: #include <unistd.h>
1.277 deraadt 56: #include <limits.h>
1.1 markus 57:
1.216 deraadt 58: #include "xmalloc.h"
1.51 markus 59: #include "ssh.h"
60: #include "ssh2.h"
1.59 djm 61: #include "sshpty.h"
1.1 markus 62: #include "packet.h"
63: #include "buffer.h"
1.173 djm 64: #include "match.h"
1.1 markus 65: #include "uidswap.h"
66: #include "compat.h"
1.78 markus 67: #include "channels.h"
1.216 deraadt 68: #include "key.h"
69: #include "cipher.h"
70: #include "kex.h"
71: #include "hostfile.h"
1.2 markus 72: #include "auth.h"
1.19 markus 73: #include "auth-options.h"
1.266 markus 74: #include "authfd.h"
1.50 markus 75: #include "pathnames.h"
1.51 markus 76: #include "log.h"
1.274 millert 77: #include "misc.h"
1.51 markus 78: #include "servconf.h"
1.59 djm 79: #include "sshlogin.h"
1.51 markus 80: #include "serverloop.h"
81: #include "canohost.h"
1.55 itojun 82: #include "session.h"
1.216 deraadt 83: #ifdef GSSAPI
84: #include "ssh-gss.h"
85: #endif
1.130 provos 86: #include "monitor_wrap.h"
1.225 markus 87: #include "sftp.h"
1.290 djm 88: #include "atomicio.h"
1.171 markus 89:
90: #ifdef KRB5
91: #include <kafs.h>
1.161 markus 92: #endif
93:
1.242 djm 94: #define IS_INTERNAL_SFTP(c) \
95: (!strncmp(c, INTERNAL_SFTP_NAME, sizeof(INTERNAL_SFTP_NAME) - 1) && \
96: (c[sizeof(INTERNAL_SFTP_NAME) - 1] == '\0' || \
97: c[sizeof(INTERNAL_SFTP_NAME) - 1] == ' ' || \
98: c[sizeof(INTERNAL_SFTP_NAME) - 1] == '\t'))
99:
1.1 markus 100: /* func */
101:
102: Session *session_new(void);
1.256 djm 103: void session_set_fds(Session *, int, int, int, int, int);
1.165 markus 104: void session_pty_cleanup(Session *);
1.94 itojun 105: void session_proctitle(Session *);
106: int session_setup_x11fwd(Session *);
1.237 djm 107: int do_exec_pty(Session *, const char *);
108: int do_exec_no_pty(Session *, const char *);
109: int do_exec(Session *, const char *);
1.94 itojun 110: void do_login(Session *, const char *);
111: void do_child(Session *, const char *);
1.73 djm 112: void do_motd(void);
1.94 itojun 113: int check_quietlogin(Session *, const char *);
1.1 markus 114:
1.94 itojun 115: static void do_authenticated2(Authctxt *);
116:
117: static int session_pty_req(Session *);
1.65 markus 118:
1.1 markus 119: /* import */
120: extern ServerOptions options;
121: extern char *__progname;
122: extern int debug_flag;
1.45 markus 123: extern u_int utmp_len;
1.21 markus 124: extern int startup_pipe;
1.74 markus 125: extern void destroy_sensitive_data(void);
1.179 dtucker 126: extern Buffer loginmsg;
1.21 markus 127:
1.34 markus 128: /* original command from peer. */
1.92 markus 129: const char *original_command = NULL;
1.34 markus 130:
1.1 markus 131: /* data */
1.237 djm 132: static int sessions_first_unused = -1;
133: static int sessions_nalloc = 0;
134: static Session *sessions = NULL;
1.1 markus 135:
1.248 djm 136: #define SUBSYSTEM_NONE 0
137: #define SUBSYSTEM_EXT 1
138: #define SUBSYSTEM_INT_SFTP 2
139: #define SUBSYSTEM_INT_SFTP_ERROR 3
1.225 markus 140:
1.129 provos 141: login_cap_t *lc;
1.28 millert 142:
1.165 markus 143: static int is_child = 0;
1.279 djm 144: static int in_chroot = 0;
1.165 markus 145:
1.290 djm 146: /* File containing userauth info, if ExposeAuthInfo set */
147: static char *auth_info_file = NULL;
148:
1.136 markus 149: /* Name and directory of socket for authentication agent forwarding. */
150: static char *auth_sock_name = NULL;
151: static char *auth_sock_dir = NULL;
152:
153: /* removes the agent forwarding socket */
154:
155: static void
1.165 markus 156: auth_sock_cleanup_proc(struct passwd *pw)
1.136 markus 157: {
158: if (auth_sock_name != NULL) {
159: temporarily_use_uid(pw);
160: unlink(auth_sock_name);
161: rmdir(auth_sock_dir);
162: auth_sock_name = NULL;
163: restore_uid();
164: }
165: }
166:
167: static int
168: auth_input_request_forwarding(struct passwd * pw)
169: {
170: Channel *nc;
1.237 djm 171: int sock = -1;
1.136 markus 172:
173: if (auth_sock_name != NULL) {
174: error("authentication forwarding requested twice.");
175: return 0;
176: }
177:
178: /* Temporarily drop privileged uid for mkdir/bind. */
179: temporarily_use_uid(pw);
180:
181: /* Allocate a buffer for the socket name, and format the name. */
1.237 djm 182: auth_sock_dir = xstrdup("/tmp/ssh-XXXXXXXXXX");
1.136 markus 183:
184: /* Create private directory for socket */
185: if (mkdtemp(auth_sock_dir) == NULL) {
186: packet_send_debug("Agent forwarding disabled: "
187: "mkdtemp() failed: %.100s", strerror(errno));
188: restore_uid();
1.265 djm 189: free(auth_sock_dir);
1.136 markus 190: auth_sock_dir = NULL;
1.237 djm 191: goto authsock_err;
1.136 markus 192: }
1.237 djm 193:
194: xasprintf(&auth_sock_name, "%s/agent.%ld",
195: auth_sock_dir, (long) getpid());
1.136 markus 196:
1.274 millert 197: /* Start a Unix listener on auth_sock_name. */
198: sock = unix_listener(auth_sock_name, SSH_LISTEN_BACKLOG, 0);
1.136 markus 199:
200: /* Restore the privileged uid. */
201: restore_uid();
202:
1.274 millert 203: /* Check for socket/bind/listen failure. */
204: if (sock < 0)
1.237 djm 205: goto authsock_err;
1.136 markus 206:
207: /* Allocate a channel for the authentication agent socket. */
208: nc = channel_new("auth socket",
209: SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1,
210: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.156 markus 211: 0, "auth socket", 1);
1.245 djm 212: nc->path = xstrdup(auth_sock_name);
1.136 markus 213: return 1;
1.237 djm 214:
215: authsock_err:
1.265 djm 216: free(auth_sock_name);
1.237 djm 217: if (auth_sock_dir != NULL) {
218: rmdir(auth_sock_dir);
1.265 djm 219: free(auth_sock_dir);
1.237 djm 220: }
221: if (sock != -1)
222: close(sock);
223: auth_sock_name = NULL;
224: auth_sock_dir = NULL;
225: return 0;
1.136 markus 226: }
227:
1.179 dtucker 228: static void
229: display_loginmsg(void)
230: {
1.183 djm 231: if (buffer_len(&loginmsg) > 0) {
232: buffer_append(&loginmsg, "\0", 1);
233: printf("%s", (char *)buffer_ptr(&loginmsg));
234: buffer_clear(&loginmsg);
235: }
1.179 dtucker 236: }
1.136 markus 237:
1.290 djm 238: static void
239: prepare_auth_info_file(struct passwd *pw, struct sshbuf *info)
240: {
241: int fd = -1, success = 0;
242:
243: if (!options.expose_userauth_info || info == NULL)
244: return;
245:
246: temporarily_use_uid(pw);
247: auth_info_file = xstrdup("/tmp/sshauth.XXXXXXXXXXXXXXX");
248: if ((fd = mkstemp(auth_info_file)) == -1) {
249: error("%s: mkstemp: %s", __func__, strerror(errno));
250: goto out;
251: }
252: if (atomicio(vwrite, fd, sshbuf_mutable_ptr(info),
253: sshbuf_len(info)) != sshbuf_len(info)) {
254: error("%s: write: %s", __func__, strerror(errno));
255: goto out;
256: }
257: if (close(fd) != 0) {
258: error("%s: close: %s", __func__, strerror(errno));
259: goto out;
260: }
261: success = 1;
262: out:
263: if (!success) {
264: if (fd != -1)
265: close(fd);
266: free(auth_info_file);
267: auth_info_file = NULL;
268: }
269: restore_uid();
270: }
271:
1.65 markus 272: void
273: do_authenticated(Authctxt *authctxt)
274: {
1.153 markus 275: setproctitle("%s", authctxt->pw->pw_name);
276:
1.65 markus 277: /* setup the channel layer */
1.274 millert 278: /* XXX - streamlocal? */
1.286 djm 279: if (no_port_forwarding_flag || options.disable_forwarding ||
1.261 djm 280: (options.allow_tcp_forwarding & FORWARD_LOCAL) == 0)
281: channel_disable_adm_local_opens();
282: else
1.65 markus 283: channel_permit_all_opens();
1.252 dtucker 284:
285: auth_debug_send();
1.65 markus 286:
1.290 djm 287: prepare_auth_info_file(authctxt->pw, authctxt->session_info);
288:
1.283 markus 289: do_authenticated2(authctxt);
1.290 djm 290:
1.165 markus 291: do_cleanup(authctxt);
1.65 markus 292: }
293:
1.282 djm 294: /* Check untrusted xauth strings for metacharacters */
295: static int
296: xauth_valid_string(const char *s)
297: {
298: size_t i;
299:
300: for (i = 0; s[i] != '\0'; i++) {
301: if (!isalnum((u_char)s[i]) &&
302: s[i] != '.' && s[i] != ':' && s[i] != '/' &&
303: s[i] != '-' && s[i] != '_')
304: return 0;
305: }
306: return 1;
307: }
308:
1.269 dtucker 309: #define USE_PIPES 1
1.1 markus 310: /*
311: * This is called to fork and execute a command when we have no tty. This
312: * will call do_child from the child, and server_loop from the parent after
313: * setting up file descriptors and such.
314: */
1.237 djm 315: int
1.63 markus 316: do_exec_no_pty(Session *s, const char *command)
1.1 markus 317: {
1.137 mpech 318: pid_t pid;
1.238 markus 319: #ifdef USE_PIPES
320: int pin[2], pout[2], perr[2];
321:
1.253 djm 322: if (s == NULL)
323: fatal("do_exec_no_pty: no session");
324:
1.238 markus 325: /* Allocate pipes for communicating with the program. */
326: if (pipe(pin) < 0) {
327: error("%s: pipe in: %.100s", __func__, strerror(errno));
328: return -1;
329: }
330: if (pipe(pout) < 0) {
331: error("%s: pipe out: %.100s", __func__, strerror(errno));
332: close(pin[0]);
333: close(pin[1]);
334: return -1;
335: }
1.256 djm 336: if (pipe(perr) < 0) {
337: error("%s: pipe err: %.100s", __func__,
338: strerror(errno));
339: close(pin[0]);
340: close(pin[1]);
341: close(pout[0]);
342: close(pout[1]);
343: return -1;
1.238 markus 344: }
345: #else
1.237 djm 346: int inout[2], err[2];
1.1 markus 347:
1.253 djm 348: if (s == NULL)
349: fatal("do_exec_no_pty: no session");
350:
1.1 markus 351: /* Uses socket pairs to communicate with the program. */
1.237 djm 352: if (socketpair(AF_UNIX, SOCK_STREAM, 0, inout) < 0) {
353: error("%s: socketpair #1: %.100s", __func__, strerror(errno));
354: return -1;
355: }
1.256 djm 356: if (socketpair(AF_UNIX, SOCK_STREAM, 0, err) < 0) {
357: error("%s: socketpair #2: %.100s", __func__,
358: strerror(errno));
359: close(inout[0]);
360: close(inout[1]);
361: return -1;
1.237 djm 362: }
1.238 markus 363: #endif
1.237 djm 364:
1.9 markus 365: session_proctitle(s);
1.1 markus 366:
367: /* Fork the child. */
1.237 djm 368: switch ((pid = fork())) {
369: case -1:
370: error("%s: fork: %.100s", __func__, strerror(errno));
1.238 markus 371: #ifdef USE_PIPES
372: close(pin[0]);
373: close(pin[1]);
374: close(pout[0]);
375: close(pout[1]);
1.256 djm 376: close(perr[0]);
1.238 markus 377: close(perr[1]);
378: #else
1.237 djm 379: close(inout[0]);
380: close(inout[1]);
381: close(err[0]);
1.256 djm 382: close(err[1]);
1.238 markus 383: #endif
1.237 djm 384: return -1;
385: case 0:
1.165 markus 386: is_child = 1;
1.144 markus 387:
1.1 markus 388: /*
389: * Create a new session and process group since the 4.4BSD
390: * setlogin() affects the entire process group.
391: */
392: if (setsid() < 0)
393: error("setsid failed: %.100s", strerror(errno));
394:
1.238 markus 395: #ifdef USE_PIPES
396: /*
397: * Redirect stdin. We close the parent side of the socket
398: * pair, and make the child side the standard input.
399: */
400: close(pin[1]);
401: if (dup2(pin[0], 0) < 0)
402: perror("dup2 stdin");
403: close(pin[0]);
404:
405: /* Redirect stdout. */
406: close(pout[0]);
407: if (dup2(pout[1], 1) < 0)
408: perror("dup2 stdout");
409: close(pout[1]);
410:
411: /* Redirect stderr. */
1.256 djm 412: close(perr[0]);
1.238 markus 413: if (dup2(perr[1], 2) < 0)
414: perror("dup2 stderr");
415: close(perr[1]);
416: #else
1.1 markus 417: /*
418: * Redirect stdin, stdout, and stderr. Stdin and stdout will
419: * use the same socket, as some programs (particularly rdist)
420: * seem to depend on it.
421: */
422: close(inout[1]);
1.256 djm 423: close(err[1]);
1.1 markus 424: if (dup2(inout[0], 0) < 0) /* stdin */
425: perror("dup2 stdin");
1.237 djm 426: if (dup2(inout[0], 1) < 0) /* stdout (same as stdin) */
1.1 markus 427: perror("dup2 stdout");
1.238 markus 428: close(inout[0]);
1.1 markus 429: if (dup2(err[0], 2) < 0) /* stderr */
430: perror("dup2 stderr");
1.238 markus 431: close(err[0]);
432: #endif
1.1 markus 433:
434: /* Do processing for the child (exec command etc). */
1.60 markus 435: do_child(s, command);
1.1 markus 436: /* NOTREACHED */
1.237 djm 437: default:
438: break;
1.1 markus 439: }
1.237 djm 440:
1.1 markus 441: s->pid = pid;
1.47 markus 442: /* Set interactive/non-interactive mode. */
1.257 djm 443: packet_set_interactive(s->display != NULL,
444: options.ip_qos_interactive, options.ip_qos_bulk);
1.1 markus 445:
1.238 markus 446: #ifdef USE_PIPES
447: /* We are the parent. Close the child sides of the pipes. */
448: close(pin[0]);
449: close(pout[1]);
450: close(perr[1]);
451:
1.283 markus 452: session_set_fds(s, pin[1], pout[0], perr[0],
453: s->is_subsystem, 0);
1.238 markus 454: #else
1.1 markus 455: /* We are the parent. Close the child sides of the socket pairs. */
456: close(inout[0]);
457: close(err[0]);
458:
459: /*
460: * Enter the interactive session. Note: server_loop must be able to
461: * handle the case that fdin and fdout are the same.
462: */
1.283 markus 463: session_set_fds(s, inout[1], inout[1], err[1],
464: s->is_subsystem, 0);
1.238 markus 465: #endif
1.237 djm 466: return 0;
1.1 markus 467: }
468:
469: /*
470: * This is called to fork and execute a command when we have a tty. This
471: * will call do_child from the child, and server_loop from the parent after
472: * setting up file descriptors, controlling tty, updating wtmp, utmp,
473: * lastlog, and other such operations.
474: */
1.237 djm 475: int
1.63 markus 476: do_exec_pty(Session *s, const char *command)
1.1 markus 477: {
478: int fdout, ptyfd, ttyfd, ptymaster;
479: pid_t pid;
480:
481: if (s == NULL)
482: fatal("do_exec_pty: no session");
483: ptyfd = s->ptyfd;
484: ttyfd = s->ttyfd;
485:
1.237 djm 486: /*
487: * Create another descriptor of the pty master side for use as the
488: * standard input. We could use the original descriptor, but this
489: * simplifies code in server_loop. The descriptor is bidirectional.
490: * Do this before forking (and cleanup in the child) so as to
491: * detect and gracefully fail out-of-fd conditions.
492: */
493: if ((fdout = dup(ptyfd)) < 0) {
494: error("%s: dup #1: %s", __func__, strerror(errno));
495: close(ttyfd);
496: close(ptyfd);
497: return -1;
498: }
499: /* we keep a reference to the pty master */
500: if ((ptymaster = dup(ptyfd)) < 0) {
501: error("%s: dup #2: %s", __func__, strerror(errno));
502: close(ttyfd);
503: close(ptyfd);
504: close(fdout);
505: return -1;
506: }
507:
1.1 markus 508: /* Fork the child. */
1.237 djm 509: switch ((pid = fork())) {
510: case -1:
511: error("%s: fork: %.100s", __func__, strerror(errno));
512: close(fdout);
513: close(ptymaster);
514: close(ttyfd);
515: close(ptyfd);
516: return -1;
517: case 0:
1.165 markus 518: is_child = 1;
1.97 markus 519:
1.237 djm 520: close(fdout);
521: close(ptymaster);
522:
1.1 markus 523: /* Close the master side of the pseudo tty. */
524: close(ptyfd);
525:
526: /* Make the pseudo tty our controlling tty. */
527: pty_make_controlling_tty(&ttyfd, s->tty);
528:
1.103 markus 529: /* Redirect stdin/stdout/stderr from the pseudo tty. */
530: if (dup2(ttyfd, 0) < 0)
531: error("dup2 stdin: %s", strerror(errno));
532: if (dup2(ttyfd, 1) < 0)
533: error("dup2 stdout: %s", strerror(errno));
534: if (dup2(ttyfd, 2) < 0)
535: error("dup2 stderr: %s", strerror(errno));
1.1 markus 536:
537: /* Close the extra descriptor for the pseudo tty. */
538: close(ttyfd);
539:
1.24 markus 540: /* record login, etc. similar to login(1) */
1.285 otto 541: do_login(s, command);
1.228 djm 542:
1.237 djm 543: /*
544: * Do common processing for the child, such as execing
545: * the command.
546: */
1.60 markus 547: do_child(s, command);
1.1 markus 548: /* NOTREACHED */
1.237 djm 549: default:
550: break;
1.1 markus 551: }
552: s->pid = pid;
553:
554: /* Parent. Close the slave side of the pseudo tty. */
555: close(ttyfd);
556:
1.237 djm 557: /* Enter interactive session. */
1.1 markus 558: s->ptymaster = ptymaster;
1.257 djm 559: packet_set_interactive(1,
560: options.ip_qos_interactive, options.ip_qos_bulk);
1.283 markus 561: session_set_fds(s, ptyfd, fdout, -1, 1, 1);
1.237 djm 562: return 0;
1.24 markus 563: }
564:
1.90 markus 565: /*
566: * This is called to fork and execute a command. If another command is
567: * to be forced, execute that instead.
568: */
1.237 djm 569: int
1.90 markus 570: do_exec(Session *s, const char *command)
571: {
1.281 djm 572: struct ssh *ssh = active_state; /* XXX */
1.237 djm 573: int ret;
1.280 djm 574: const char *forced = NULL, *tty = NULL;
575: char session_type[1024];
1.237 djm 576:
1.210 dtucker 577: if (options.adm_forced_command) {
578: original_command = command;
579: command = options.adm_forced_command;
1.267 djm 580: forced = "(config)";
1.210 dtucker 581: } else if (forced_command) {
1.90 markus 582: original_command = command;
583: command = forced_command;
1.267 djm 584: forced = "(key-option)";
585: }
586: if (forced != NULL) {
1.248 djm 587: if (IS_INTERNAL_SFTP(command)) {
588: s->is_subsystem = s->is_subsystem ?
589: SUBSYSTEM_INT_SFTP : SUBSYSTEM_INT_SFTP_ERROR;
590: } else if (s->is_subsystem)
1.225 markus 591: s->is_subsystem = SUBSYSTEM_EXT;
1.267 djm 592: snprintf(session_type, sizeof(session_type),
593: "forced-command %s '%.900s'", forced, command);
594: } else if (s->is_subsystem) {
595: snprintf(session_type, sizeof(session_type),
596: "subsystem '%.900s'", s->subsys);
597: } else if (command == NULL) {
598: snprintf(session_type, sizeof(session_type), "shell");
599: } else {
600: /* NB. we don't log unforced commands to preserve privacy */
601: snprintf(session_type, sizeof(session_type), "command");
1.90 markus 602: }
1.163 markus 603:
1.267 djm 604: if (s->ttyfd != -1) {
605: tty = s->tty;
606: if (strncmp(tty, "/dev/", 5) == 0)
607: tty += 5;
608: }
609:
1.280 djm 610: verbose("Starting session: %s%s%s for %s from %.200s port %d id %d",
1.267 djm 611: session_type,
612: tty == NULL ? "" : " on ",
613: tty == NULL ? "" : tty,
614: s->pw->pw_name,
1.281 djm 615: ssh_remote_ipaddr(ssh),
616: ssh_remote_port(ssh),
1.280 djm 617: s->self);
1.267 djm 618:
1.163 markus 619: #ifdef GSSAPI
620: if (options.gss_authentication) {
621: temporarily_use_uid(s->pw);
622: ssh_gssapi_storecreds();
623: restore_uid();
624: }
625: #endif
1.90 markus 626: if (s->ttyfd != -1)
1.237 djm 627: ret = do_exec_pty(s, command);
1.90 markus 628: else
1.237 djm 629: ret = do_exec_no_pty(s, command);
1.90 markus 630:
1.92 markus 631: original_command = NULL;
1.179 dtucker 632:
633: /*
634: * Clear loginmsg: it's the child's responsibility to display
635: * it to the user, otherwise multiple sessions may accumulate
636: * multiple copies of the login messages.
637: */
638: buffer_clear(&loginmsg);
1.237 djm 639:
640: return ret;
1.90 markus 641: }
642:
643:
1.24 markus 644: /* administrative, login(1)-like work */
645: void
1.41 markus 646: do_login(Session *s, const char *command)
1.24 markus 647: {
1.281 djm 648: struct ssh *ssh = active_state; /* XXX */
1.24 markus 649: socklen_t fromlen;
650: struct sockaddr_storage from;
651: struct passwd * pw = s->pw;
652: pid_t pid = getpid();
653:
654: /*
655: * Get IP address of client. If the connection is not a socket, let
656: * the address be 0.0.0.0.
657: */
658: memset(&from, 0, sizeof(from));
1.148 stevesk 659: fromlen = sizeof(from);
1.24 markus 660: if (packet_connection_is_on_socket()) {
661: if (getpeername(packet_get_connection_in(),
1.200 deraadt 662: (struct sockaddr *)&from, &fromlen) < 0) {
1.24 markus 663: debug("getpeername: %.100s", strerror(errno));
1.165 markus 664: cleanup_exit(255);
1.24 markus 665: }
666: }
1.25 markus 667:
1.24 markus 668: /* Record that there was a login on that tty from the remote host. */
1.133 markus 669: if (!use_privsep)
670: record_login(pid, s->tty, pw->pw_name, pw->pw_uid,
1.281 djm 671: session_get_remote_name_or_ip(ssh, utmp_len,
1.158 markus 672: options.use_dns),
1.148 stevesk 673: (struct sockaddr *)&from, fromlen);
1.24 markus 674:
1.73 djm 675: if (check_quietlogin(s, command))
1.24 markus 676: return;
1.73 djm 677:
1.179 dtucker 678: display_loginmsg();
1.73 djm 679:
680: do_motd();
681: }
682:
683: /*
684: * Display the message of the day.
685: */
686: void
687: do_motd(void)
688: {
689: FILE *f;
690: char buf[256];
691:
1.24 markus 692: if (options.print_motd) {
1.28 millert 693: f = fopen(login_getcapstr(lc, "welcome", "/etc/motd",
694: "/etc/motd"), "r");
1.24 markus 695: if (f) {
696: while (fgets(buf, sizeof(buf), f))
697: fputs(buf, stdout);
698: fclose(f);
699: }
1.2 markus 700: }
1.73 djm 701: }
702:
703:
704: /*
705: * Check for quiet login, either .hushlogin or command given.
706: */
707: int
708: check_quietlogin(Session *s, const char *command)
709: {
710: char buf[256];
1.96 dugsong 711: struct passwd *pw = s->pw;
1.73 djm 712: struct stat st;
713:
714: /* Return 1 if .hushlogin exists or a command given. */
715: if (command != NULL)
716: return 1;
717: snprintf(buf, sizeof(buf), "%.200s/.hushlogin", pw->pw_dir);
718: if (login_getcapbool(lc, "hushlogin", 0) || stat(buf, &st) >= 0)
719: return 1;
720: return 0;
1.1 markus 721: }
722:
723: /*
724: * Reads environment variables from the given file and adds/overrides them
725: * into the environment. If the file does not exist, this does nothing.
726: * Otherwise, it must consist of empty lines, comments (line starts with '#')
727: * and assignments of the form name=value. No other forms are allowed.
728: */
1.94 itojun 729: static void
1.45 markus 730: read_environment_file(char ***env, u_int *envsize,
1.112 deraadt 731: const char *filename)
1.1 markus 732: {
733: FILE *f;
734: char buf[4096];
735: char *cp, *value;
1.142 deraadt 736: u_int lineno = 0;
1.1 markus 737:
738: f = fopen(filename, "r");
739: if (!f)
740: return;
741:
742: while (fgets(buf, sizeof(buf), f)) {
1.142 deraadt 743: if (++lineno > 1000)
744: fatal("Too many lines in environment file %s", filename);
1.1 markus 745: for (cp = buf; *cp == ' ' || *cp == '\t'; cp++)
746: ;
747: if (!*cp || *cp == '#' || *cp == '\n')
748: continue;
1.224 gilles 749:
750: cp[strcspn(cp, "\n")] = '\0';
751:
1.1 markus 752: value = strchr(cp, '=');
753: if (value == NULL) {
1.142 deraadt 754: fprintf(stderr, "Bad line %u in %.100s\n", lineno,
755: filename);
1.1 markus 756: continue;
757: }
1.14 deraadt 758: /*
759: * Replace the equals sign by nul, and advance value to
760: * the value string.
761: */
1.1 markus 762: *value = '\0';
763: value++;
764: child_set_env(env, envsize, cp, value);
765: }
766: fclose(f);
767: }
768:
1.127 markus 769: static char **
770: do_setup_env(Session *s, const char *shell)
1.1 markus 771: {
1.281 djm 772: struct ssh *ssh = active_state; /* XXX */
1.1 markus 773: char buf[256];
1.127 markus 774: u_int i, envsize;
1.154 markus 775: char **env, *laddr;
1.127 markus 776: struct passwd *pw = s->pw;
1.1 markus 777:
778: /* Initialize the environment. */
779: envsize = 100;
1.220 djm 780: env = xcalloc(envsize, sizeof(char *));
1.1 markus 781: env[0] = NULL;
782:
1.161 markus 783: #ifdef GSSAPI
1.168 djm 784: /* Allow any GSSAPI methods that we've used to alter
1.161 markus 785: * the childs environment as they see fit
786: */
787: ssh_gssapi_do_child(&env, &envsize);
788: #endif
789:
1.284 djm 790: /* Set basic environment. */
791: for (i = 0; i < s->num_env; i++)
792: child_set_env(&env, &envsize, s->env[i].name, s->env[i].val);
793:
794: child_set_env(&env, &envsize, "USER", pw->pw_name);
795: child_set_env(&env, &envsize, "LOGNAME", pw->pw_name);
796: child_set_env(&env, &envsize, "HOME", pw->pw_dir);
797: if (setusercontext(lc, pw, pw->pw_uid, LOGIN_SETPATH) < 0)
798: child_set_env(&env, &envsize, "PATH", _PATH_STDPATH);
799: else
800: child_set_env(&env, &envsize, "PATH", getenv("PATH"));
801:
802: snprintf(buf, sizeof buf, "%.200s/%.50s", _PATH_MAILDIR, pw->pw_name);
803: child_set_env(&env, &envsize, "MAIL", buf);
804:
805: /* Normal systems set SHELL by default. */
806: child_set_env(&env, &envsize, "SHELL", shell);
1.1 markus 807:
808: if (getenv("TZ"))
809: child_set_env(&env, &envsize, "TZ", getenv("TZ"));
810:
811: /* Set custom environment options from RSA authentication. */
1.284 djm 812: while (custom_environment) {
813: struct envstring *ce = custom_environment;
814: char *str = ce->s;
815:
816: for (i = 0; str[i] != '=' && str[i]; i++)
817: ;
818: if (str[i] == '=') {
819: str[i] = 0;
820: child_set_env(&env, &envsize, str, str + i + 1);
821: }
822: custom_environment = ce->next;
823: free(ce->s);
824: free(ce);
1.1 markus 825: }
826:
1.149 stevesk 827: /* SSH_CLIENT deprecated */
1.1 markus 828: snprintf(buf, sizeof buf, "%.50s %d %d",
1.281 djm 829: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
830: ssh_local_port(ssh));
1.1 markus 831: child_set_env(&env, &envsize, "SSH_CLIENT", buf);
1.149 stevesk 832:
1.154 markus 833: laddr = get_local_ipaddr(packet_get_connection_in());
1.149 stevesk 834: snprintf(buf, sizeof buf, "%.50s %d %.50s %d",
1.281 djm 835: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
836: laddr, ssh_local_port(ssh));
1.265 djm 837: free(laddr);
1.149 stevesk 838: child_set_env(&env, &envsize, "SSH_CONNECTION", buf);
1.1 markus 839:
1.290 djm 840: if (auth_info_file != NULL)
841: child_set_env(&env, &envsize, "SSH_USER_AUTH", auth_info_file);
1.60 markus 842: if (s->ttyfd != -1)
843: child_set_env(&env, &envsize, "SSH_TTY", s->tty);
844: if (s->term)
845: child_set_env(&env, &envsize, "TERM", s->term);
846: if (s->display)
847: child_set_env(&env, &envsize, "DISPLAY", s->display);
1.34 markus 848: if (original_command)
849: child_set_env(&env, &envsize, "SSH_ORIGINAL_COMMAND",
850: original_command);
1.96 dugsong 851: #ifdef KRB5
852: if (s->authctxt->krb5_ticket_file)
853: child_set_env(&env, &envsize, "KRB5CCNAME",
1.112 deraadt 854: s->authctxt->krb5_ticket_file);
1.96 dugsong 855: #endif
1.136 markus 856: if (auth_sock_name != NULL)
1.1 markus 857: child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME,
1.136 markus 858: auth_sock_name);
1.1 markus 859:
860: /* read $HOME/.ssh/environment. */
1.284 djm 861: if (options.permit_user_env) {
1.14 deraadt 862: snprintf(buf, sizeof buf, "%.200s/.ssh/environment",
863: pw->pw_dir);
1.1 markus 864: read_environment_file(&env, &envsize, buf);
865: }
866: if (debug_flag) {
867: /* dump the environment */
868: fprintf(stderr, "Environment:\n");
869: for (i = 0; env[i]; i++)
870: fprintf(stderr, " %.200s\n", env[i]);
871: }
1.127 markus 872: return env;
873: }
874:
875: /*
876: * Run $HOME/.ssh/rc, /etc/ssh/sshrc, or xauth (whichever is found
877: * first in this order).
878: */
879: static void
880: do_rc_files(Session *s, const char *shell)
881: {
882: FILE *f = NULL;
883: char cmd[1024];
884: int do_xauth;
885: struct stat st;
886:
887: do_xauth =
888: s->display != NULL && s->auth_proto != NULL && s->auth_data != NULL;
889:
1.231 djm 890: /* ignore _PATH_SSH_USER_RC for subsystems and admin forced commands */
1.232 djm 891: if (!s->is_subsystem && options.adm_forced_command == NULL &&
1.273 djm 892: !no_user_rc && options.permit_user_rc &&
893: stat(_PATH_SSH_USER_RC, &st) >= 0) {
1.127 markus 894: snprintf(cmd, sizeof cmd, "%s -c '%s %s'",
895: shell, _PATH_BSHELL, _PATH_SSH_USER_RC);
896: if (debug_flag)
897: fprintf(stderr, "Running %s\n", cmd);
898: f = popen(cmd, "w");
899: if (f) {
900: if (do_xauth)
901: fprintf(f, "%s %s\n", s->auth_proto,
902: s->auth_data);
903: pclose(f);
904: } else
905: fprintf(stderr, "Could not run %s\n",
906: _PATH_SSH_USER_RC);
907: } else if (stat(_PATH_SSH_SYSTEM_RC, &st) >= 0) {
908: if (debug_flag)
909: fprintf(stderr, "Running %s %s\n", _PATH_BSHELL,
910: _PATH_SSH_SYSTEM_RC);
911: f = popen(_PATH_BSHELL " " _PATH_SSH_SYSTEM_RC, "w");
912: if (f) {
913: if (do_xauth)
914: fprintf(f, "%s %s\n", s->auth_proto,
915: s->auth_data);
916: pclose(f);
917: } else
918: fprintf(stderr, "Could not run %s\n",
919: _PATH_SSH_SYSTEM_RC);
920: } else if (do_xauth && options.xauth_location != NULL) {
921: /* Add authority data to .Xauthority if appropriate. */
922: if (debug_flag) {
923: fprintf(stderr,
1.151 stevesk 924: "Running %.500s remove %.100s\n",
1.165 markus 925: options.xauth_location, s->auth_display);
1.151 stevesk 926: fprintf(stderr,
927: "%.500s add %.100s %.100s %.100s\n",
1.127 markus 928: options.xauth_location, s->auth_display,
929: s->auth_proto, s->auth_data);
930: }
931: snprintf(cmd, sizeof cmd, "%s -q -",
932: options.xauth_location);
933: f = popen(cmd, "w");
934: if (f) {
1.151 stevesk 935: fprintf(f, "remove %s\n",
936: s->auth_display);
1.127 markus 937: fprintf(f, "add %s %s %s\n",
938: s->auth_display, s->auth_proto,
939: s->auth_data);
940: pclose(f);
941: } else {
942: fprintf(stderr, "Could not run %s\n",
943: cmd);
944: }
945: }
946: }
947:
948: static void
949: do_nologin(struct passwd *pw)
950: {
951: FILE *f = NULL;
1.251 dtucker 952: char buf[1024], *nl, *def_nl = _PATH_NOLOGIN;
953: struct stat sb;
1.127 markus 954:
1.260 guenther 955: if (login_getcapbool(lc, "ignorenologin", 0) || pw->pw_uid == 0)
1.251 dtucker 956: return;
957: nl = login_getcapstr(lc, "nologin", def_nl, def_nl);
958:
959: if (stat(nl, &sb) == -1) {
960: if (nl != def_nl)
1.265 djm 961: free(nl);
1.251 dtucker 962: return;
963: }
964:
965: /* /etc/nologin exists. Print its contents if we can and exit. */
966: logit("User %.100s not allowed because %s exists", pw->pw_name, nl);
967: if ((f = fopen(nl, "r")) != NULL) {
1.127 markus 968: while (fgets(buf, sizeof(buf), f))
969: fputs(buf, stderr);
970: fclose(f);
971: }
1.251 dtucker 972: exit(254);
1.127 markus 973: }
974:
1.226 djm 975: /*
976: * Chroot into a directory after checking it for safety: all path components
977: * must be root-owned directories with strict permissions.
978: */
979: static void
980: safely_chroot(const char *path, uid_t uid)
981: {
982: const char *cp;
1.277 deraadt 983: char component[PATH_MAX];
1.226 djm 984: struct stat st;
985:
986: if (*path != '/')
987: fatal("chroot path does not begin at root");
988: if (strlen(path) >= sizeof(component))
989: fatal("chroot path too long");
990:
991: /*
992: * Descend the path, checking that each component is a
993: * root-owned directory with strict permissions.
994: */
995: for (cp = path; cp != NULL;) {
996: if ((cp = strchr(cp, '/')) == NULL)
997: strlcpy(component, path, sizeof(component));
998: else {
999: cp++;
1000: memcpy(component, path, cp - path);
1001: component[cp - path] = '\0';
1002: }
1003:
1004: debug3("%s: checking '%s'", __func__, component);
1005:
1006: if (stat(component, &st) != 0)
1007: fatal("%s: stat(\"%s\"): %s", __func__,
1008: component, strerror(errno));
1009: if (st.st_uid != 0 || (st.st_mode & 022) != 0)
1010: fatal("bad ownership or modes for chroot "
1011: "directory %s\"%s\"",
1012: cp == NULL ? "" : "component ", component);
1013: if (!S_ISDIR(st.st_mode))
1014: fatal("chroot path %s\"%s\" is not a directory",
1015: cp == NULL ? "" : "component ", component);
1016:
1017: }
1018:
1019: if (chdir(path) == -1)
1020: fatal("Unable to chdir to chroot path \"%s\": "
1021: "%s", path, strerror(errno));
1022: if (chroot(path) == -1)
1023: fatal("chroot(\"%s\"): %s", path, strerror(errno));
1024: if (chdir("/") == -1)
1025: fatal("%s: chdir(/) after chroot: %s",
1026: __func__, strerror(errno));
1027: verbose("Changed root directory to \"%s\"", path);
1028: }
1029:
1.127 markus 1030: /* Set login name, uid, gid, and groups. */
1.130 provos 1031: void
1.127 markus 1032: do_setusercontext(struct passwd *pw)
1033: {
1.227 djm 1034: char *chroot_path, *tmp;
1035:
1.127 markus 1036: if (getuid() == 0 || geteuid() == 0) {
1.226 djm 1037: /* Prepare groups */
1.127 markus 1038: if (setusercontext(lc, pw, pw->pw_uid,
1.226 djm 1039: (LOGIN_SETALL & ~(LOGIN_SETPATH|LOGIN_SETUSER))) < 0) {
1.127 markus 1040: perror("unable to set user context");
1041: exit(1);
1042: }
1.226 djm 1043:
1.279 djm 1044: if (!in_chroot && options.chroot_directory != NULL &&
1.226 djm 1045: strcasecmp(options.chroot_directory, "none") != 0) {
1.227 djm 1046: tmp = tilde_expand_filename(options.chroot_directory,
1047: pw->pw_uid);
1048: chroot_path = percent_expand(tmp, "h", pw->pw_dir,
1049: "u", pw->pw_name, (char *)NULL);
1.226 djm 1050: safely_chroot(chroot_path, pw->pw_uid);
1.227 djm 1051: free(tmp);
1.226 djm 1052: free(chroot_path);
1.264 djm 1053: /* Make sure we don't attempt to chroot again */
1054: free(options.chroot_directory);
1055: options.chroot_directory = NULL;
1.279 djm 1056: in_chroot = 1;
1.226 djm 1057: }
1058:
1059: /* Set UID */
1060: if (setusercontext(lc, pw, pw->pw_uid, LOGIN_SETUSER) < 0) {
1061: perror("unable to set user context (setuser)");
1062: exit(1);
1063: }
1.264 djm 1064: } else if (options.chroot_directory != NULL &&
1065: strcasecmp(options.chroot_directory, "none") != 0) {
1066: fatal("server lacks privileges to chroot to ChrootDirectory");
1.263 dtucker 1067: }
1.264 djm 1068:
1.127 markus 1069: if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid)
1070: fatal("Failed to set uids to %u.", (u_int) pw->pw_uid);
1071: }
1072:
1.131 markus 1073: static void
1.172 markus 1074: do_pwchange(Session *s)
1075: {
1.179 dtucker 1076: fflush(NULL);
1.172 markus 1077: fprintf(stderr, "WARNING: Your password has expired.\n");
1078: if (s->ttyfd != -1) {
1.178 deraadt 1079: fprintf(stderr,
1.172 markus 1080: "You must change your password now and login again!\n");
1081: execl(_PATH_PASSWD_PROG, "passwd", (char *)NULL);
1082: perror("passwd");
1083: } else {
1084: fprintf(stderr,
1085: "Password change required but no TTY available.\n");
1086: }
1087: exit(1);
1088: }
1089:
1090: static void
1091: child_close_fds(void)
1092: {
1.276 djm 1093: extern int auth_sock;
1.266 markus 1094:
1.276 djm 1095: if (auth_sock != -1) {
1096: close(auth_sock);
1097: auth_sock = -1;
1.266 markus 1098: }
1099:
1.172 markus 1100: if (packet_get_connection_in() == packet_get_connection_out())
1101: close(packet_get_connection_in());
1102: else {
1103: close(packet_get_connection_in());
1104: close(packet_get_connection_out());
1105: }
1106: /*
1107: * Close all descriptors related to channels. They will still remain
1108: * open in the parent.
1109: */
1110: /* XXX better use close-on-exec? -markus */
1111: channel_close_all();
1112:
1113: /*
1114: * Close any extra file descriptors. Note that there may still be
1115: * descriptors left by system functions. They will be closed later.
1116: */
1117: endpwent();
1118:
1119: /*
1.188 djm 1120: * Close any extra open file descriptors so that we don't have them
1.172 markus 1121: * hanging around in clients. Note that we want to do this after
1122: * initgroups, because at least on Solaris 2.3 it leaves file
1123: * descriptors open.
1124: */
1.258 djm 1125: closefrom(STDERR_FILENO + 1);
1.172 markus 1126: }
1127:
1.127 markus 1128: /*
1129: * Performs common processing for the child, such as setting up the
1130: * environment, closing extra file descriptors, setting the user and group
1131: * ids, and executing the command or shell.
1132: */
1.225 markus 1133: #define ARGV_MAX 10
1.127 markus 1134: void
1135: do_child(Session *s, const char *command)
1136: {
1137: extern char **environ;
1138: char **env;
1.225 markus 1139: char *argv[ARGV_MAX];
1.284 djm 1140: const char *shell, *shell0;
1.127 markus 1141: struct passwd *pw = s->pw;
1.239 djm 1142: int r = 0;
1.127 markus 1143:
1144: /* remove hostkey from the child's memory */
1145: destroy_sensitive_data();
1.287 markus 1146: packet_clear_keys();
1.127 markus 1147:
1.172 markus 1148: /* Force a password change */
1149: if (s->authctxt->force_pwchange) {
1150: do_setusercontext(pw);
1151: child_close_fds();
1152: do_pwchange(s);
1153: exit(1);
1154: }
1155:
1.127 markus 1156: /*
1157: * Login(1) does this as well, and it needs uid 0 for the "-h"
1158: * switch, so we let login(1) to this for us.
1159: */
1.284 djm 1160: do_nologin(pw);
1161: do_setusercontext(pw);
1.127 markus 1162:
1163: /*
1164: * Get the shell from the password data. An empty shell field is
1165: * legal, and means /bin/sh.
1166: */
1167: shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
1.152 markus 1168:
1169: /*
1170: * Make sure $SHELL points to the shell from the password file,
1171: * even if shell is overridden from login.conf
1172: */
1173: env = do_setup_env(s, shell);
1174:
1.127 markus 1175: shell = login_getcapstr(lc, "shell", (char *)shell, (char *)shell);
1176:
1.1 markus 1177: /*
1178: * Close the connection descriptors; note that this is the child, and
1179: * the server will still have the socket open, and it is important
1180: * that we do not shutdown it. Note that the descriptors cannot be
1181: * closed before building the environment, as we call
1.281 djm 1182: * ssh_remote_ipaddr there.
1.1 markus 1183: */
1.172 markus 1184: child_close_fds();
1.1 markus 1185:
1186: /*
1.125 deraadt 1187: * Must take new environment into use so that .ssh/rc,
1188: * /etc/ssh/sshrc and xauth are run in the proper environment.
1.1 markus 1189: */
1190: environ = env;
1.170 jakob 1191:
1192: #ifdef KRB5
1193: /*
1194: * At this point, we check to see if AFS is active and if we have
1195: * a valid Kerberos 5 TGT. If so, it seems like a good idea to see
1196: * if we can (and need to) extend the ticket into an AFS token. If
1197: * we don't do this, we run into potential problems if the user's
1198: * home directory is in AFS and it's not world-readable.
1199: */
1200:
1201: if (options.kerberos_get_afs_token && k_hasafs() &&
1.185 djm 1202: (s->authctxt->krb5_ctx != NULL)) {
1.170 jakob 1203: char cell[64];
1204:
1205: debug("Getting AFS token");
1206:
1207: k_setpag();
1208:
1209: if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0)
1210: krb5_afslog(s->authctxt->krb5_ctx,
1211: s->authctxt->krb5_fwd_ccache, cell, NULL);
1212:
1213: krb5_afslog_home(s->authctxt->krb5_ctx,
1214: s->authctxt->krb5_fwd_ccache, NULL, NULL, pw->pw_dir);
1215: }
1216: #endif
1.104 markus 1217:
1.188 djm 1218: /* Change current directory to the user's home directory. */
1.104 markus 1219: if (chdir(pw->pw_dir) < 0) {
1.239 djm 1220: /* Suppress missing homedir warning for chroot case */
1221: r = login_getcapbool(lc, "requirehome", 0);
1.279 djm 1222: if (r || !in_chroot) {
1.239 djm 1223: fprintf(stderr, "Could not chdir to home "
1224: "directory %s: %s\n", pw->pw_dir,
1225: strerror(errno));
1.279 djm 1226: }
1.239 djm 1227: if (r)
1.104 markus 1228: exit(1);
1229: }
1.230 djm 1230:
1231: closefrom(STDERR_FILENO + 1);
1.1 markus 1232:
1.284 djm 1233: do_rc_files(s, shell);
1.67 markus 1234:
1235: /* restore SIGPIPE for child */
1.217 stevesk 1236: signal(SIGPIPE, SIG_DFL);
1.67 markus 1237:
1.248 djm 1238: if (s->is_subsystem == SUBSYSTEM_INT_SFTP_ERROR) {
1239: printf("This service allows sftp connections only.\n");
1240: fflush(NULL);
1241: exit(1);
1242: } else if (s->is_subsystem == SUBSYSTEM_INT_SFTP) {
1.225 markus 1243: extern int optind, optreset;
1244: int i;
1245: char *p, *args;
1246:
1.246 stevesk 1247: setproctitle("%s@%s", s->pw->pw_name, INTERNAL_SFTP_NAME);
1.243 millert 1248: args = xstrdup(command ? command : "sftp-server");
1.225 markus 1249: for (i = 0, (p = strtok(args, " ")); p; (p = strtok(NULL, " ")))
1250: if (i < ARGV_MAX - 1)
1251: argv[i++] = p;
1252: argv[i] = NULL;
1253: optind = optreset = 1;
1254: __progname = argv[0];
1.226 djm 1255: exit(sftp_server_main(i, argv, s->pw));
1.225 markus 1256: }
1.247 djm 1257:
1258: fflush(NULL);
1.225 markus 1259:
1.127 markus 1260: /* Get the last component of the shell name. */
1261: if ((shell0 = strrchr(shell, '/')) != NULL)
1262: shell0++;
1263: else
1264: shell0 = shell;
1265:
1.1 markus 1266: /*
1267: * If we have no command, execute the shell. In this case, the shell
1268: * name to be passed in argv[0] is preceded by '-' to indicate that
1269: * this is a login shell.
1270: */
1271: if (!command) {
1.127 markus 1272: char argv0[256];
1.1 markus 1273:
1.127 markus 1274: /* Start the shell. Set initial character to '-'. */
1275: argv0[0] = '-';
1.1 markus 1276:
1.127 markus 1277: if (strlcpy(argv0 + 1, shell0, sizeof(argv0) - 1)
1.128 markus 1278: >= sizeof(argv0) - 1) {
1.127 markus 1279: errno = EINVAL;
1.1 markus 1280: perror(shell);
1281: exit(1);
1.127 markus 1282: }
1.1 markus 1283:
1.127 markus 1284: /* Execute the shell. */
1285: argv[0] = argv0;
1286: argv[1] = NULL;
1287: execve(shell, argv, env);
1288:
1289: /* Executing the shell failed. */
1290: perror(shell);
1291: exit(1);
1.1 markus 1292: }
1293: /*
1294: * Execute the command using the user's shell. This uses the -c
1295: * option to execute the command.
1296: */
1.127 markus 1297: argv[0] = (char *) shell0;
1.1 markus 1298: argv[1] = "-c";
1299: argv[2] = (char *) command;
1300: argv[3] = NULL;
1301: execve(shell, argv, env);
1302: perror(shell);
1303: exit(1);
1304: }
1305:
1.237 djm 1306: void
1307: session_unused(int id)
1308: {
1309: debug3("%s: session id %d unused", __func__, id);
1310: if (id >= options.max_sessions ||
1311: id >= sessions_nalloc) {
1312: fatal("%s: insane session id %d (max %d nalloc %d)",
1313: __func__, id, options.max_sessions, sessions_nalloc);
1314: }
1.270 tedu 1315: memset(&sessions[id], 0, sizeof(*sessions));
1.237 djm 1316: sessions[id].self = id;
1317: sessions[id].used = 0;
1318: sessions[id].chanid = -1;
1319: sessions[id].ptyfd = -1;
1320: sessions[id].ttyfd = -1;
1321: sessions[id].ptymaster = -1;
1322: sessions[id].x11_chanids = NULL;
1323: sessions[id].next_unused = sessions_first_unused;
1324: sessions_first_unused = id;
1325: }
1326:
1.1 markus 1327: Session *
1328: session_new(void)
1329: {
1.237 djm 1330: Session *s, *tmp;
1331:
1332: if (sessions_first_unused == -1) {
1333: if (sessions_nalloc >= options.max_sessions)
1334: return NULL;
1335: debug2("%s: allocate (allocated %d max %d)",
1336: __func__, sessions_nalloc, options.max_sessions);
1.288 deraadt 1337: tmp = xrecallocarray(sessions, sessions_nalloc,
1338: sessions_nalloc + 1, sizeof(*sessions));
1.237 djm 1339: if (tmp == NULL) {
1340: error("%s: cannot allocate %d sessions",
1341: __func__, sessions_nalloc + 1);
1342: return NULL;
1343: }
1344: sessions = tmp;
1345: session_unused(sessions_nalloc++);
1346: }
1347:
1348: if (sessions_first_unused >= sessions_nalloc ||
1349: sessions_first_unused < 0) {
1350: fatal("%s: insane first_unused %d max %d nalloc %d",
1351: __func__, sessions_first_unused, options.max_sessions,
1352: sessions_nalloc);
1353: }
1354:
1355: s = &sessions[sessions_first_unused];
1356: if (s->used) {
1357: fatal("%s: session %d already used",
1358: __func__, sessions_first_unused);
1359: }
1360: sessions_first_unused = s->next_unused;
1361: s->used = 1;
1362: s->next_unused = -1;
1363: debug("session_new: session %d", s->self);
1364:
1365: return s;
1.1 markus 1366: }
1367:
1.94 itojun 1368: static void
1.1 markus 1369: session_dump(void)
1370: {
1371: int i;
1.237 djm 1372: for (i = 0; i < sessions_nalloc; i++) {
1.1 markus 1373: Session *s = &sessions[i];
1.237 djm 1374:
1375: debug("dump: used %d next_unused %d session %d %p "
1376: "channel %d pid %ld",
1.1 markus 1377: s->used,
1.237 djm 1378: s->next_unused,
1.1 markus 1379: s->self,
1380: s,
1381: s->chanid,
1.137 mpech 1382: (long)s->pid);
1.1 markus 1383: }
1384: }
1385:
1.2 markus 1386: int
1.97 markus 1387: session_open(Authctxt *authctxt, int chanid)
1.2 markus 1388: {
1389: Session *s = session_new();
1390: debug("session_open: channel %d", chanid);
1391: if (s == NULL) {
1392: error("no more sessions");
1393: return 0;
1394: }
1.97 markus 1395: s->authctxt = authctxt;
1396: s->pw = authctxt->pw;
1.167 djm 1397: if (s->pw == NULL || !authctxt->valid)
1.54 stevesk 1398: fatal("no user for session %d", s->self);
1.2 markus 1399: debug("session_open: session %d: link with channel %d", s->self, chanid);
1400: s->chanid = chanid;
1401: return 1;
1402: }
1403:
1.130 provos 1404: Session *
1405: session_by_tty(char *tty)
1406: {
1407: int i;
1.237 djm 1408: for (i = 0; i < sessions_nalloc; i++) {
1.130 provos 1409: Session *s = &sessions[i];
1410: if (s->used && s->ttyfd != -1 && strcmp(s->tty, tty) == 0) {
1411: debug("session_by_tty: session %d tty %s", i, tty);
1412: return s;
1413: }
1414: }
1415: debug("session_by_tty: unknown tty %.100s", tty);
1416: session_dump();
1417: return NULL;
1418: }
1419:
1.94 itojun 1420: static Session *
1.2 markus 1421: session_by_channel(int id)
1422: {
1423: int i;
1.237 djm 1424: for (i = 0; i < sessions_nalloc; i++) {
1.2 markus 1425: Session *s = &sessions[i];
1426: if (s->used && s->chanid == id) {
1.237 djm 1427: debug("session_by_channel: session %d channel %d",
1428: i, id);
1.2 markus 1429: return s;
1430: }
1431: }
1432: debug("session_by_channel: unknown channel %d", id);
1433: session_dump();
1434: return NULL;
1435: }
1436:
1.94 itojun 1437: static Session *
1.184 djm 1438: session_by_x11_channel(int id)
1439: {
1440: int i, j;
1441:
1.237 djm 1442: for (i = 0; i < sessions_nalloc; i++) {
1.184 djm 1443: Session *s = &sessions[i];
1444:
1445: if (s->x11_chanids == NULL || !s->used)
1446: continue;
1447: for (j = 0; s->x11_chanids[j] != -1; j++) {
1448: if (s->x11_chanids[j] == id) {
1449: debug("session_by_x11_channel: session %d "
1450: "channel %d", s->self, id);
1451: return s;
1452: }
1453: }
1454: }
1455: debug("session_by_x11_channel: unknown channel %d", id);
1456: session_dump();
1457: return NULL;
1458: }
1459:
1460: static Session *
1.2 markus 1461: session_by_pid(pid_t pid)
1462: {
1463: int i;
1.137 mpech 1464: debug("session_by_pid: pid %ld", (long)pid);
1.237 djm 1465: for (i = 0; i < sessions_nalloc; i++) {
1.2 markus 1466: Session *s = &sessions[i];
1467: if (s->used && s->pid == pid)
1468: return s;
1469: }
1.137 mpech 1470: error("session_by_pid: unknown pid %ld", (long)pid);
1.2 markus 1471: session_dump();
1472: return NULL;
1473: }
1474:
1.94 itojun 1475: static int
1.2 markus 1476: session_window_change_req(Session *s)
1477: {
1478: s->col = packet_get_int();
1479: s->row = packet_get_int();
1480: s->xpixel = packet_get_int();
1481: s->ypixel = packet_get_int();
1.116 markus 1482: packet_check_eom();
1.2 markus 1483: pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1484: return 1;
1485: }
1486:
1.94 itojun 1487: static int
1.2 markus 1488: session_pty_req(Session *s)
1489: {
1.45 markus 1490: u_int len;
1.72 stevesk 1491: int n_bytes;
1.132 markus 1492:
1.268 djm 1493: if (no_pty_flag || !options.permit_tty) {
1.86 markus 1494: debug("Allocating a pty not permitted for this authentication.");
1.19 markus 1495: return 0;
1.86 markus 1496: }
1497: if (s->ttyfd != -1) {
1498: packet_disconnect("Protocol error: you already have a pty.");
1.3 markus 1499: return 0;
1.86 markus 1500: }
1501:
1.2 markus 1502: s->term = packet_get_string(&len);
1.283 markus 1503: s->col = packet_get_int();
1504: s->row = packet_get_int();
1.2 markus 1505: s->xpixel = packet_get_int();
1506: s->ypixel = packet_get_int();
1507:
1508: if (strcmp(s->term, "") == 0) {
1.265 djm 1509: free(s->term);
1.2 markus 1510: s->term = NULL;
1511: }
1.86 markus 1512:
1.2 markus 1513: /* Allocate a pty and open it. */
1.86 markus 1514: debug("Allocating pty.");
1.237 djm 1515: if (!PRIVSEP(pty_allocate(&s->ptyfd, &s->ttyfd, s->tty,
1516: sizeof(s->tty)))) {
1.265 djm 1517: free(s->term);
1.2 markus 1518: s->term = NULL;
1519: s->ptyfd = -1;
1520: s->ttyfd = -1;
1521: error("session_pty_req: session %d alloc failed", s->self);
1.3 markus 1522: return 0;
1.2 markus 1523: }
1524: debug("session_pty_req: session %d alloc %s", s->self, s->tty);
1.86 markus 1525:
1.283 markus 1526: n_bytes = packet_remaining();
1.86 markus 1527: tty_parse_modes(s->ttyfd, &n_bytes);
1528:
1.130 provos 1529: if (!use_privsep)
1530: pty_setowner(s->pw, s->tty);
1.86 markus 1531:
1532: /* Set window size from the packet. */
1.2 markus 1533: pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1534:
1.116 markus 1535: packet_check_eom();
1.9 markus 1536: session_proctitle(s);
1.2 markus 1537: return 1;
1538: }
1539:
1.94 itojun 1540: static int
1.7 markus 1541: session_subsystem_req(Session *s)
1542: {
1.105 markus 1543: struct stat st;
1.45 markus 1544: u_int len;
1.7 markus 1545: int success = 0;
1.267 djm 1546: char *prog, *cmd;
1.182 djm 1547: u_int i;
1.7 markus 1548:
1.267 djm 1549: s->subsys = packet_get_string(&len);
1.116 markus 1550: packet_check_eom();
1.267 djm 1551: debug2("subsystem request for %.100s by user %s", s->subsys,
1.255 djm 1552: s->pw->pw_name);
1.18 jakob 1553:
1554: for (i = 0; i < options.num_subsystems; i++) {
1.267 djm 1555: if (strcmp(s->subsys, options.subsystem_name[i]) == 0) {
1.205 djm 1556: prog = options.subsystem_command[i];
1557: cmd = options.subsystem_args[i];
1.249 dtucker 1558: if (strcmp(INTERNAL_SFTP_NAME, prog) == 0) {
1.225 markus 1559: s->is_subsystem = SUBSYSTEM_INT_SFTP;
1.249 dtucker 1560: debug("subsystem: %s", prog);
1.225 markus 1561: } else {
1.249 dtucker 1562: if (stat(prog, &st) < 0)
1563: debug("subsystem: cannot stat %s: %s",
1564: prog, strerror(errno));
1.225 markus 1565: s->is_subsystem = SUBSYSTEM_EXT;
1.249 dtucker 1566: debug("subsystem: exec() %s", cmd);
1.105 markus 1567: }
1.237 djm 1568: success = do_exec(s, cmd) == 0;
1.122 markus 1569: break;
1.18 jakob 1570: }
1571: }
1572:
1573: if (!success)
1.267 djm 1574: logit("subsystem request for %.100s by user %s failed, "
1575: "subsystem not found", s->subsys, s->pw->pw_name);
1.7 markus 1576:
1577: return success;
1578: }
1579:
1.94 itojun 1580: static int
1.7 markus 1581: session_x11_req(Session *s)
1582: {
1.81 markus 1583: int success;
1.7 markus 1584:
1.184 djm 1585: if (s->auth_proto != NULL || s->auth_data != NULL) {
1586: error("session_x11_req: session %d: "
1.190 stevesk 1587: "x11 forwarding already active", s->self);
1.184 djm 1588: return 0;
1589: }
1.7 markus 1590: s->single_connection = packet_get_char();
1591: s->auth_proto = packet_get_string(NULL);
1592: s->auth_data = packet_get_string(NULL);
1593: s->screen = packet_get_int();
1.116 markus 1594: packet_check_eom();
1.7 markus 1595:
1.282 djm 1596: if (xauth_valid_string(s->auth_proto) &&
1597: xauth_valid_string(s->auth_data))
1598: success = session_setup_x11fwd(s);
1599: else {
1600: success = 0;
1601: error("Invalid X11 forwarding data");
1602: }
1.81 markus 1603: if (!success) {
1.265 djm 1604: free(s->auth_proto);
1605: free(s->auth_data);
1.84 markus 1606: s->auth_proto = NULL;
1607: s->auth_data = NULL;
1.7 markus 1608: }
1.81 markus 1609: return success;
1.7 markus 1610: }
1611:
1.94 itojun 1612: static int
1.19 markus 1613: session_shell_req(Session *s)
1614: {
1.116 markus 1615: packet_check_eom();
1.237 djm 1616: return do_exec(s, NULL) == 0;
1.19 markus 1617: }
1618:
1.94 itojun 1619: static int
1.19 markus 1620: session_exec_req(Session *s)
1621: {
1.237 djm 1622: u_int len, success;
1623:
1.19 markus 1624: char *command = packet_get_string(&len);
1.116 markus 1625: packet_check_eom();
1.237 djm 1626: success = do_exec(s, command) == 0;
1.265 djm 1627: free(command);
1.237 djm 1628: return success;
1.19 markus 1629: }
1630:
1.94 itojun 1631: static int
1.157 markus 1632: session_break_req(Session *s)
1633: {
1634:
1.175 deraadt 1635: packet_get_int(); /* ignored */
1.157 markus 1636: packet_check_eom();
1637:
1.259 djm 1638: if (s->ptymaster == -1 || tcsendbreak(s->ptymaster, 0) < 0)
1.157 markus 1639: return 0;
1640: return 1;
1641: }
1642:
1643: static int
1.173 djm 1644: session_env_req(Session *s)
1645: {
1646: char *name, *val;
1647: u_int name_len, val_len, i;
1648:
1.271 djm 1649: name = packet_get_cstring(&name_len);
1650: val = packet_get_cstring(&val_len);
1.173 djm 1651: packet_check_eom();
1652:
1653: /* Don't set too many environment variables */
1654: if (s->num_env > 128) {
1655: debug2("Ignoring env request %s: too many env vars", name);
1656: goto fail;
1657: }
1658:
1659: for (i = 0; i < options.num_accept_env; i++) {
1660: if (match_pattern(name, options.accept_env[i])) {
1661: debug2("Setting env %d: %s=%s", s->num_env, name, val);
1.288 deraadt 1662: s->env = xrecallocarray(s->env, s->num_env,
1663: s->num_env + 1, sizeof(*s->env));
1.173 djm 1664: s->env[s->num_env].name = name;
1665: s->env[s->num_env].val = val;
1666: s->num_env++;
1667: return (1);
1668: }
1669: }
1670: debug2("Ignoring env request %s: disallowed name", name);
1671:
1672: fail:
1.265 djm 1673: free(name);
1674: free(val);
1.173 djm 1675: return (0);
1676: }
1677:
1678: static int
1.43 markus 1679: session_auth_agent_req(Session *s)
1680: {
1681: static int called = 0;
1.116 markus 1682: packet_check_eom();
1.235 pyr 1683: if (no_agent_forwarding_flag || !options.allow_agent_forwarding) {
1.44 markus 1684: debug("session_auth_agent_req: no_agent_forwarding_flag");
1685: return 0;
1686: }
1.43 markus 1687: if (called) {
1688: return 0;
1689: } else {
1690: called = 1;
1691: return auth_input_request_forwarding(s->pw);
1692: }
1693: }
1694:
1.123 markus 1695: int
1696: session_input_channel_req(Channel *c, const char *rtype)
1.2 markus 1697: {
1698: int success = 0;
1699: Session *s;
1700:
1.123 markus 1701: if ((s = session_by_channel(c->self)) == NULL) {
1.155 itojun 1702: logit("session_input_channel_req: no session %d req %.100s",
1.123 markus 1703: c->self, rtype);
1704: return 0;
1705: }
1706: debug("session_input_channel_req: session %d req %s", s->self, rtype);
1.2 markus 1707:
1708: /*
1.64 markus 1709: * a session is in LARVAL state until a shell, a command
1710: * or a subsystem is executed
1.2 markus 1711: */
1712: if (c->type == SSH_CHANNEL_LARVAL) {
1713: if (strcmp(rtype, "shell") == 0) {
1.19 markus 1714: success = session_shell_req(s);
1.2 markus 1715: } else if (strcmp(rtype, "exec") == 0) {
1.19 markus 1716: success = session_exec_req(s);
1.2 markus 1717: } else if (strcmp(rtype, "pty-req") == 0) {
1.221 stevesk 1718: success = session_pty_req(s);
1.7 markus 1719: } else if (strcmp(rtype, "x11-req") == 0) {
1720: success = session_x11_req(s);
1.43 markus 1721: } else if (strcmp(rtype, "auth-agent-req@openssh.com") == 0) {
1722: success = session_auth_agent_req(s);
1.7 markus 1723: } else if (strcmp(rtype, "subsystem") == 0) {
1724: success = session_subsystem_req(s);
1.173 djm 1725: } else if (strcmp(rtype, "env") == 0) {
1726: success = session_env_req(s);
1.2 markus 1727: }
1728: }
1729: if (strcmp(rtype, "window-change") == 0) {
1730: success = session_window_change_req(s);
1.177 djm 1731: } else if (strcmp(rtype, "break") == 0) {
1732: success = session_break_req(s);
1.2 markus 1733: }
1.177 djm 1734:
1.123 markus 1735: return success;
1.2 markus 1736: }
1737:
1738: void
1.256 djm 1739: session_set_fds(Session *s, int fdin, int fdout, int fderr, int ignore_fderr,
1740: int is_tty)
1.2 markus 1741: {
1742: /*
1743: * now that have a child and a pipe to the child,
1744: * we can activate our channel and register the fd's
1745: */
1746: if (s->chanid == -1)
1747: fatal("no channel for session %d", s->self);
1748: channel_set_fds(s->chanid,
1749: fdout, fdin, fderr,
1.256 djm 1750: ignore_fderr ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ,
1.241 dtucker 1751: 1, is_tty, CHAN_SES_WINDOW_DEFAULT);
1.2 markus 1752: }
1753:
1.85 markus 1754: /*
1755: * Function to perform pty cleanup. Also called if we get aborted abnormally
1756: * (e.g., due to a dropped connection).
1757: */
1.130 provos 1758: void
1.165 markus 1759: session_pty_cleanup2(Session *s)
1.1 markus 1760: {
1.85 markus 1761: if (s == NULL) {
1762: error("session_pty_cleanup: no session");
1763: return;
1764: }
1765: if (s->ttyfd == -1)
1.1 markus 1766: return;
1767:
1.54 stevesk 1768: debug("session_pty_cleanup: session %d release %s", s->self, s->tty);
1.1 markus 1769:
1770: /* Record that the user has logged out. */
1.85 markus 1771: if (s->pid != 0)
1772: record_logout(s->pid, s->tty);
1.1 markus 1773:
1774: /* Release the pseudo-tty. */
1.130 provos 1775: if (getuid() == 0)
1776: pty_release(s->tty);
1.1 markus 1777:
1778: /*
1779: * Close the server side of the socket pairs. We must do this after
1780: * the pty cleanup, so that another process doesn't get this pty
1781: * while we're still cleaning up.
1782: */
1.237 djm 1783: if (s->ptymaster != -1 && close(s->ptymaster) < 0)
1784: error("close(s->ptymaster/%d): %s",
1785: s->ptymaster, strerror(errno));
1.108 markus 1786:
1787: /* unlink pty from session */
1788: s->ttyfd = -1;
1.2 markus 1789: }
1790:
1.130 provos 1791: void
1.165 markus 1792: session_pty_cleanup(Session *s)
1.130 provos 1793: {
1.165 markus 1794: PRIVSEP(session_pty_cleanup2(s));
1.130 provos 1795: }
1796:
1.147 markus 1797: static char *
1798: sig2name(int sig)
1799: {
1800: #define SSH_SIG(x) if (sig == SIG ## x) return #x
1801: SSH_SIG(ABRT);
1802: SSH_SIG(ALRM);
1803: SSH_SIG(FPE);
1804: SSH_SIG(HUP);
1805: SSH_SIG(ILL);
1806: SSH_SIG(INT);
1807: SSH_SIG(KILL);
1808: SSH_SIG(PIPE);
1809: SSH_SIG(QUIT);
1810: SSH_SIG(SEGV);
1811: SSH_SIG(TERM);
1812: SSH_SIG(USR1);
1813: SSH_SIG(USR2);
1814: #undef SSH_SIG
1815: return "SIG@openssh.com";
1816: }
1817:
1.94 itojun 1818: static void
1.184 djm 1819: session_close_x11(int id)
1820: {
1821: Channel *c;
1822:
1.189 markus 1823: if ((c = channel_by_id(id)) == NULL) {
1.184 djm 1824: debug("session_close_x11: x11 channel %d missing", id);
1825: } else {
1826: /* Detach X11 listener */
1827: debug("session_close_x11: detach x11 channel %d", id);
1828: channel_cancel_cleanup(id);
1829: if (c->ostate != CHAN_OUTPUT_CLOSED)
1830: chan_mark_dead(c);
1831: }
1832: }
1833:
1834: static void
1835: session_close_single_x11(int id, void *arg)
1836: {
1837: Session *s;
1838: u_int i;
1839:
1840: debug3("session_close_single_x11: channel %d", id);
1841: channel_cancel_cleanup(id);
1.221 stevesk 1842: if ((s = session_by_x11_channel(id)) == NULL)
1.184 djm 1843: fatal("session_close_single_x11: no x11 channel %d", id);
1844: for (i = 0; s->x11_chanids[i] != -1; i++) {
1845: debug("session_close_single_x11: session %d: "
1846: "closing channel %d", s->self, s->x11_chanids[i]);
1847: /*
1848: * The channel "id" is already closing, but make sure we
1849: * close all of its siblings.
1850: */
1851: if (s->x11_chanids[i] != id)
1852: session_close_x11(s->x11_chanids[i]);
1853: }
1.265 djm 1854: free(s->x11_chanids);
1.184 djm 1855: s->x11_chanids = NULL;
1.265 djm 1856: free(s->display);
1857: s->display = NULL;
1858: free(s->auth_proto);
1859: s->auth_proto = NULL;
1860: free(s->auth_data);
1861: s->auth_data = NULL;
1862: free(s->auth_display);
1863: s->auth_display = NULL;
1.184 djm 1864: }
1865:
1866: static void
1.2 markus 1867: session_exit_message(Session *s, int status)
1868: {
1869: Channel *c;
1.124 markus 1870:
1871: if ((c = channel_lookup(s->chanid)) == NULL)
1.85 markus 1872: fatal("session_exit_message: session %d: no channel %d",
1.2 markus 1873: s->self, s->chanid);
1.137 mpech 1874: debug("session_exit_message: session %d channel %d pid %ld",
1875: s->self, s->chanid, (long)s->pid);
1.2 markus 1876:
1877: if (WIFEXITED(status)) {
1.124 markus 1878: channel_request_start(s->chanid, "exit-status", 0);
1.2 markus 1879: packet_put_int(WEXITSTATUS(status));
1880: packet_send();
1881: } else if (WIFSIGNALED(status)) {
1.124 markus 1882: channel_request_start(s->chanid, "exit-signal", 0);
1.147 markus 1883: packet_put_cstring(sig2name(WTERMSIG(status)));
1.229 markus 1884: packet_put_char(WCOREDUMP(status)? 1 : 0);
1.2 markus 1885: packet_put_cstring("");
1886: packet_put_cstring("");
1887: packet_send();
1888: } else {
1889: /* Some weird exit cause. Just exit. */
1890: packet_disconnect("wait returned status %04x.", status);
1891: }
1892:
1893: /* disconnect channel */
1894: debug("session_exit_message: release channel %d", s->chanid);
1.187 djm 1895:
1896: /*
1897: * Adjust cleanup callback attachment to send close messages when
1.199 deraadt 1898: * the channel gets EOF. The session will be then be closed
1.187 djm 1899: * by session_close_by_channel when the childs close their fds.
1900: */
1901: channel_register_cleanup(c->self, session_close_by_channel, 1);
1902:
1.5 markus 1903: /*
1904: * emulate a write failure with 'chan_write_failed', nobody will be
1905: * interested in data we write.
1906: * Note that we must not call 'chan_read_failed', since there could
1907: * be some more data waiting in the pipe.
1908: */
1.8 markus 1909: if (c->ostate != CHAN_OUTPUT_CLOSED)
1910: chan_write_failed(c);
1.2 markus 1911: }
1912:
1.130 provos 1913: void
1.85 markus 1914: session_close(Session *s)
1.2 markus 1915: {
1.281 djm 1916: struct ssh *ssh = active_state; /* XXX */
1.182 djm 1917: u_int i;
1.173 djm 1918:
1.280 djm 1919: verbose("Close session: user %s from %.200s port %d id %d",
1920: s->pw->pw_name,
1.281 djm 1921: ssh_remote_ipaddr(ssh),
1922: ssh_remote_port(ssh),
1.280 djm 1923: s->self);
1924:
1.165 markus 1925: if (s->ttyfd != -1)
1.85 markus 1926: session_pty_cleanup(s);
1.265 djm 1927: free(s->term);
1928: free(s->display);
1929: free(s->x11_chanids);
1930: free(s->auth_display);
1931: free(s->auth_data);
1932: free(s->auth_proto);
1.267 djm 1933: free(s->subsys);
1.219 djm 1934: if (s->env != NULL) {
1935: for (i = 0; i < s->num_env; i++) {
1.265 djm 1936: free(s->env[i].name);
1937: free(s->env[i].val);
1.219 djm 1938: }
1.265 djm 1939: free(s->env);
1.173 djm 1940: }
1.9 markus 1941: session_proctitle(s);
1.237 djm 1942: session_unused(s->self);
1.2 markus 1943: }
1944:
1945: void
1946: session_close_by_pid(pid_t pid, int status)
1947: {
1948: Session *s = session_by_pid(pid);
1949: if (s == NULL) {
1.137 mpech 1950: debug("session_close_by_pid: no session for pid %ld",
1951: (long)pid);
1.2 markus 1952: return;
1953: }
1954: if (s->chanid != -1)
1955: session_exit_message(s, status);
1.187 djm 1956: if (s->ttyfd != -1)
1957: session_pty_cleanup(s);
1.197 djm 1958: s->pid = 0;
1.98 markus 1959: }
1960:
1.2 markus 1961: /*
1962: * this is called when a channel dies before
1963: * the session 'child' itself dies
1964: */
1965: void
1966: session_close_by_channel(int id, void *arg)
1967: {
1968: Session *s = session_by_channel(id);
1.187 djm 1969: u_int i;
1.184 djm 1970:
1.2 markus 1971: if (s == NULL) {
1.107 markus 1972: debug("session_close_by_channel: no session for id %d", id);
1.2 markus 1973: return;
1974: }
1.137 mpech 1975: debug("session_close_by_channel: channel %d child %ld",
1976: id, (long)s->pid);
1.107 markus 1977: if (s->pid != 0) {
1978: debug("session_close_by_channel: channel %d: has child", id);
1.108 markus 1979: /*
1980: * delay detach of session, but release pty, since
1981: * the fd's to the child are already closed
1982: */
1.165 markus 1983: if (s->ttyfd != -1)
1.108 markus 1984: session_pty_cleanup(s);
1.107 markus 1985: return;
1986: }
1987: /* detach by removing callback */
1.2 markus 1988: channel_cancel_cleanup(s->chanid);
1.187 djm 1989:
1990: /* Close any X11 listeners associated with this session */
1991: if (s->x11_chanids != NULL) {
1992: for (i = 0; s->x11_chanids[i] != -1; i++) {
1993: session_close_x11(s->x11_chanids[i]);
1994: s->x11_chanids[i] = -1;
1995: }
1996: }
1997:
1.2 markus 1998: s->chanid = -1;
1.106 markus 1999: session_close(s);
2000: }
2001:
2002: void
1.130 provos 2003: session_destroy_all(void (*closefunc)(Session *))
1.106 markus 2004: {
2005: int i;
1.237 djm 2006: for (i = 0; i < sessions_nalloc; i++) {
1.106 markus 2007: Session *s = &sessions[i];
1.130 provos 2008: if (s->used) {
2009: if (closefunc != NULL)
2010: closefunc(s);
2011: else
2012: session_close(s);
2013: }
1.2 markus 2014: }
1.9 markus 2015: }
2016:
1.94 itojun 2017: static char *
1.9 markus 2018: session_tty_list(void)
2019: {
2020: static char buf[1024];
2021: int i;
2022: buf[0] = '\0';
1.237 djm 2023: for (i = 0; i < sessions_nalloc; i++) {
1.9 markus 2024: Session *s = &sessions[i];
2025: if (s->used && s->ttyfd != -1) {
2026: if (buf[0] != '\0')
2027: strlcat(buf, ",", sizeof buf);
2028: strlcat(buf, strrchr(s->tty, '/') + 1, sizeof buf);
2029: }
2030: }
2031: if (buf[0] == '\0')
2032: strlcpy(buf, "notty", sizeof buf);
2033: return buf;
2034: }
2035:
2036: void
2037: session_proctitle(Session *s)
2038: {
2039: if (s->pw == NULL)
2040: error("no user for session %d", s->self);
2041: else
2042: setproctitle("%s@%s", s->pw->pw_name, session_tty_list());
1.81 markus 2043: }
2044:
2045: int
2046: session_setup_x11fwd(Session *s)
2047: {
2048: struct stat st;
1.109 stevesk 2049: char display[512], auth_display[512];
1.272 djm 2050: char hostname[NI_MAXHOST];
1.184 djm 2051: u_int i;
1.81 markus 2052:
2053: if (no_x11_forwarding_flag) {
2054: packet_send_debug("X11 forwarding disabled in user configuration file.");
2055: return 0;
2056: }
2057: if (!options.x11_forwarding) {
2058: debug("X11 forwarding disabled in server configuration file.");
2059: return 0;
2060: }
1.275 djm 2061: if (options.xauth_location == NULL ||
1.81 markus 2062: (stat(options.xauth_location, &st) == -1)) {
2063: packet_send_debug("No xauth program; cannot forward with spoofing.");
2064: return 0;
2065: }
1.87 markus 2066: if (s->display != NULL) {
1.81 markus 2067: debug("X11 display already set.");
2068: return 0;
2069: }
1.140 deraadt 2070: if (x11_create_display_inet(options.x11_display_offset,
2071: options.x11_use_localhost, s->single_connection,
1.184 djm 2072: &s->display_number, &s->x11_chanids) == -1) {
1.87 markus 2073: debug("x11_create_display_inet failed.");
1.81 markus 2074: return 0;
1.184 djm 2075: }
2076: for (i = 0; s->x11_chanids[i] != -1; i++) {
2077: channel_register_cleanup(s->x11_chanids[i],
1.187 djm 2078: session_close_single_x11, 0);
1.81 markus 2079: }
1.109 stevesk 2080:
2081: /* Set up a suitable value for the DISPLAY variable. */
2082: if (gethostname(hostname, sizeof(hostname)) < 0)
2083: fatal("gethostname: %.100s", strerror(errno));
2084: /*
2085: * auth_display must be used as the displayname when the
2086: * authorization entry is added with xauth(1). This will be
2087: * different than the DISPLAY string for localhost displays.
2088: */
1.119 stevesk 2089: if (options.x11_use_localhost) {
1.140 deraadt 2090: snprintf(display, sizeof display, "localhost:%u.%u",
1.109 stevesk 2091: s->display_number, s->screen);
1.140 deraadt 2092: snprintf(auth_display, sizeof auth_display, "unix:%u.%u",
1.118 stevesk 2093: s->display_number, s->screen);
1.109 stevesk 2094: s->display = xstrdup(display);
1.118 stevesk 2095: s->auth_display = xstrdup(auth_display);
1.109 stevesk 2096: } else {
1.140 deraadt 2097: snprintf(display, sizeof display, "%.400s:%u.%u", hostname,
1.109 stevesk 2098: s->display_number, s->screen);
2099: s->display = xstrdup(display);
1.118 stevesk 2100: s->auth_display = xstrdup(display);
1.109 stevesk 2101: }
2102:
1.81 markus 2103: return 1;
1.2 markus 2104: }
2105:
1.94 itojun 2106: static void
1.49 markus 2107: do_authenticated2(Authctxt *authctxt)
1.2 markus 2108: {
1.97 markus 2109: server_loop2(authctxt);
1.165 markus 2110: }
2111:
2112: void
2113: do_cleanup(Authctxt *authctxt)
2114: {
2115: static int called = 0;
2116:
2117: debug("do_cleanup");
2118:
2119: /* no cleanup if we're in the child for login shell */
2120: if (is_child)
2121: return;
2122:
2123: /* avoid double cleanup */
2124: if (called)
2125: return;
2126: called = 1;
2127:
1.218 markus 2128: if (authctxt == NULL || !authctxt->authenticated)
1.165 markus 2129: return;
2130: #ifdef KRB5
2131: if (options.kerberos_ticket_cleanup &&
2132: authctxt->krb5_ctx)
2133: krb5_cleanup_proc(authctxt);
1.161 markus 2134: #endif
1.165 markus 2135:
2136: #ifdef GSSAPI
1.283 markus 2137: if (options.gss_cleanup_creds)
1.165 markus 2138: ssh_gssapi_cleanup_creds();
2139: #endif
2140:
2141: /* remove agent socket */
2142: auth_sock_cleanup_proc(authctxt->pw);
1.290 djm 2143:
2144: /* remove userauth info */
2145: if (auth_info_file != NULL) {
2146: temporarily_use_uid(authctxt->pw);
2147: unlink(auth_info_file);
2148: restore_uid();
2149: free(auth_info_file);
2150: auth_info_file = NULL;
2151: }
1.165 markus 2152:
2153: /*
2154: * Cleanup ptys/utmp only if privsep is disabled,
2155: * or if running in monitor.
2156: */
2157: if (!use_privsep || mm_is_monitor())
2158: session_destroy_all(session_pty_cleanup2);
1.1 markus 2159: }
1.281 djm 2160:
2161: /* Return a name for the remote host that fits inside utmp_size */
2162:
2163: const char *
2164: session_get_remote_name_or_ip(struct ssh *ssh, u_int utmp_size, int use_dns)
2165: {
2166: const char *remote = "";
2167:
2168: if (utmp_size > 0)
2169: remote = auth_get_canonical_hostname(ssh, use_dns);
2170: if (utmp_size == 0 || strlen(remote) > utmp_size)
2171: remote = ssh_remote_ipaddr(ssh);
2172: return remote;
2173: }
2174:
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