Annotation of src/usr.bin/ssh/session.c, Revision 1.229
1.229 ! markus 1: /* $OpenBSD: session.c,v 1.228 2008/02/13 22:38:17 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>
1.213 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:
1.1 markus 89: /* func */
90:
91: Session *session_new(void);
1.94 itojun 92: void session_set_fds(Session *, int, int, int);
1.165 markus 93: void session_pty_cleanup(Session *);
1.94 itojun 94: void session_proctitle(Session *);
95: int session_setup_x11fwd(Session *);
96: void do_exec_pty(Session *, const char *);
97: void do_exec_no_pty(Session *, const char *);
98: void do_exec(Session *, const char *);
99: void do_login(Session *, const char *);
100: void do_child(Session *, const char *);
1.73 djm 101: void do_motd(void);
1.94 itojun 102: int check_quietlogin(Session *, const char *);
1.1 markus 103:
1.94 itojun 104: static void do_authenticated1(Authctxt *);
105: static void do_authenticated2(Authctxt *);
106:
107: static int session_pty_req(Session *);
1.65 markus 108:
1.1 markus 109: /* import */
110: extern ServerOptions options;
111: extern char *__progname;
112: extern int log_stderr;
113: extern int debug_flag;
1.45 markus 114: extern u_int utmp_len;
1.21 markus 115: extern int startup_pipe;
1.74 markus 116: extern void destroy_sensitive_data(void);
1.179 dtucker 117: extern Buffer loginmsg;
1.21 markus 118:
1.34 markus 119: /* original command from peer. */
1.92 markus 120: const char *original_command = NULL;
1.34 markus 121:
1.1 markus 122: /* data */
123: #define MAX_SESSIONS 10
124: Session sessions[MAX_SESSIONS];
125:
1.225 markus 126: #define SUBSYSTEM_NONE 0
127: #define SUBSYSTEM_EXT 1
128: #define SUBSYSTEM_INT_SFTP 2
129:
1.129 provos 130: login_cap_t *lc;
1.28 millert 131:
1.165 markus 132: static int is_child = 0;
133:
1.136 markus 134: /* Name and directory of socket for authentication agent forwarding. */
135: static char *auth_sock_name = NULL;
136: static char *auth_sock_dir = NULL;
137:
138: /* removes the agent forwarding socket */
139:
140: static void
1.165 markus 141: auth_sock_cleanup_proc(struct passwd *pw)
1.136 markus 142: {
143: if (auth_sock_name != NULL) {
144: temporarily_use_uid(pw);
145: unlink(auth_sock_name);
146: rmdir(auth_sock_dir);
147: auth_sock_name = NULL;
148: restore_uid();
149: }
150: }
151:
152: static int
153: auth_input_request_forwarding(struct passwd * pw)
154: {
155: Channel *nc;
156: int sock;
157: struct sockaddr_un sunaddr;
158:
159: if (auth_sock_name != NULL) {
160: error("authentication forwarding requested twice.");
161: return 0;
162: }
163:
164: /* Temporarily drop privileged uid for mkdir/bind. */
165: temporarily_use_uid(pw);
166:
167: /* Allocate a buffer for the socket name, and format the name. */
168: auth_sock_name = xmalloc(MAXPATHLEN);
169: auth_sock_dir = xmalloc(MAXPATHLEN);
1.166 markus 170: strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN);
1.136 markus 171:
172: /* Create private directory for socket */
173: if (mkdtemp(auth_sock_dir) == NULL) {
174: packet_send_debug("Agent forwarding disabled: "
175: "mkdtemp() failed: %.100s", strerror(errno));
176: restore_uid();
177: xfree(auth_sock_name);
178: xfree(auth_sock_dir);
179: auth_sock_name = NULL;
180: auth_sock_dir = NULL;
181: return 0;
182: }
1.137 mpech 183: snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%ld",
184: auth_sock_dir, (long) getpid());
1.136 markus 185:
186: /* Create the socket. */
187: sock = socket(AF_UNIX, SOCK_STREAM, 0);
188: if (sock < 0)
189: packet_disconnect("socket: %.100s", strerror(errno));
190:
191: /* Bind it to the name. */
192: memset(&sunaddr, 0, sizeof(sunaddr));
193: sunaddr.sun_family = AF_UNIX;
194: strlcpy(sunaddr.sun_path, auth_sock_name, sizeof(sunaddr.sun_path));
195:
1.200 deraadt 196: if (bind(sock, (struct sockaddr *)&sunaddr, sizeof(sunaddr)) < 0)
1.136 markus 197: packet_disconnect("bind: %.100s", strerror(errno));
198:
199: /* Restore the privileged uid. */
200: restore_uid();
201:
202: /* Start listening on the socket. */
1.169 markus 203: if (listen(sock, SSH_LISTEN_BACKLOG) < 0)
1.136 markus 204: packet_disconnect("listen: %.100s", strerror(errno));
205:
206: /* Allocate a channel for the authentication agent socket. */
207: nc = channel_new("auth socket",
208: SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1,
209: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.156 markus 210: 0, "auth socket", 1);
1.136 markus 211: strlcpy(nc->path, auth_sock_name, sizeof(nc->path));
212: return 1;
213: }
214:
1.179 dtucker 215: static void
216: display_loginmsg(void)
217: {
1.183 djm 218: if (buffer_len(&loginmsg) > 0) {
219: buffer_append(&loginmsg, "\0", 1);
220: printf("%s", (char *)buffer_ptr(&loginmsg));
221: buffer_clear(&loginmsg);
222: }
1.179 dtucker 223: }
1.136 markus 224:
1.65 markus 225: void
226: do_authenticated(Authctxt *authctxt)
227: {
1.153 markus 228: setproctitle("%s", authctxt->pw->pw_name);
229:
1.65 markus 230: /* setup the channel layer */
231: if (!no_port_forwarding_flag && options.allow_tcp_forwarding)
232: channel_permit_all_opens();
233:
234: if (compat20)
235: do_authenticated2(authctxt);
236: else
237: do_authenticated1(authctxt);
1.79 markus 238:
1.165 markus 239: do_cleanup(authctxt);
1.65 markus 240: }
241:
1.1 markus 242: /*
243: * Prepares for an interactive session. This is called after the user has
244: * been successfully authenticated. During this message exchange, pseudo
245: * terminals are allocated, X11, TCP/IP, and authentication agent forwardings
246: * are requested, etc.
247: */
1.94 itojun 248: static void
1.65 markus 249: do_authenticated1(Authctxt *authctxt)
1.1 markus 250: {
251: Session *s;
1.65 markus 252: char *command;
1.117 markus 253: int success, type, screen_flag;
1.139 deraadt 254: int enable_compression_after_reply = 0;
255: u_int proto_len, data_len, dlen, compression_level = 0;
1.1 markus 256:
1.61 markus 257: s = session_new();
1.181 markus 258: if (s == NULL) {
259: error("no more sessions");
260: return;
261: }
1.96 dugsong 262: s->authctxt = authctxt;
1.65 markus 263: s->pw = authctxt->pw;
1.28 millert 264:
1.1 markus 265: /*
266: * We stay in this loop until the client requests to execute a shell
267: * or a command.
268: */
269: for (;;) {
1.65 markus 270: success = 0;
1.1 markus 271:
272: /* Get a packet from the client. */
1.117 markus 273: type = packet_read();
1.1 markus 274:
275: /* Process the packet. */
276: switch (type) {
277: case SSH_CMSG_REQUEST_COMPRESSION:
278: compression_level = packet_get_int();
1.116 markus 279: packet_check_eom();
1.1 markus 280: if (compression_level < 1 || compression_level > 9) {
1.180 markus 281: packet_send_debug("Received invalid compression level %d.",
1.112 deraadt 282: compression_level);
1.138 markus 283: break;
284: }
1.186 markus 285: if (options.compression == COMP_NONE) {
1.138 markus 286: debug2("compression disabled");
1.1 markus 287: break;
288: }
289: /* Enable compression after we have responded with SUCCESS. */
290: enable_compression_after_reply = 1;
291: success = 1;
292: break;
293:
294: case SSH_CMSG_REQUEST_PTY:
1.86 markus 295: success = session_pty_req(s);
1.1 markus 296: break;
297:
298: case SSH_CMSG_X11_REQUEST_FORWARDING:
299: s->auth_proto = packet_get_string(&proto_len);
300: s->auth_data = packet_get_string(&data_len);
301:
1.57 markus 302: screen_flag = packet_get_protocol_flags() &
303: SSH_PROTOFLAG_SCREEN_NUMBER;
304: debug2("SSH_PROTOFLAG_SCREEN_NUMBER: %d", screen_flag);
305:
306: if (packet_remaining() == 4) {
307: if (!screen_flag)
308: debug2("Buggy client: "
309: "X11 screen flag missing");
1.1 markus 310: s->screen = packet_get_int();
1.56 markus 311: } else {
1.1 markus 312: s->screen = 0;
1.56 markus 313: }
1.116 markus 314: packet_check_eom();
1.81 markus 315: success = session_setup_x11fwd(s);
316: if (!success) {
317: xfree(s->auth_proto);
318: xfree(s->auth_data);
1.84 markus 319: s->auth_proto = NULL;
320: s->auth_data = NULL;
1.1 markus 321: }
322: break;
323:
324: case SSH_CMSG_AGENT_REQUEST_FORWARDING:
325: if (no_agent_forwarding_flag || compat13) {
326: debug("Authentication agent forwarding not permitted for this authentication.");
327: break;
328: }
329: debug("Received authentication agent forwarding request.");
1.65 markus 330: success = auth_input_request_forwarding(s->pw);
1.1 markus 331: break;
332:
333: case SSH_CMSG_PORT_FORWARD_REQUEST:
334: if (no_port_forwarding_flag) {
335: debug("Port forwarding not permitted for this authentication.");
1.39 markus 336: break;
337: }
338: if (!options.allow_tcp_forwarding) {
339: debug("Port forwarding not permitted.");
1.1 markus 340: break;
341: }
342: debug("Received TCP/IP port forwarding request.");
1.208 markus 343: if (channel_input_port_forward_request(s->pw->pw_uid == 0,
344: options.gateway_ports) < 0) {
345: debug("Port forwarding failed.");
346: break;
347: }
1.1 markus 348: success = 1;
349: break;
350:
351: case SSH_CMSG_MAX_PACKET_SIZE:
352: if (packet_set_maxsize(packet_get_int()) > 0)
353: success = 1;
354: break;
355:
356: case SSH_CMSG_EXEC_SHELL:
357: case SSH_CMSG_EXEC_CMD:
358: if (type == SSH_CMSG_EXEC_CMD) {
359: command = packet_get_string(&dlen);
360: debug("Exec command '%.500s'", command);
1.92 markus 361: do_exec(s, command);
362: xfree(command);
1.1 markus 363: } else {
1.92 markus 364: do_exec(s, NULL);
1.1 markus 365: }
1.116 markus 366: packet_check_eom();
1.82 markus 367: session_close(s);
1.1 markus 368: return;
369:
370: default:
371: /*
372: * Any unknown messages in this phase are ignored,
373: * and a failure message is returned.
374: */
1.155 itojun 375: logit("Unknown packet type received after authentication: %d", type);
1.1 markus 376: }
377: packet_start(success ? SSH_SMSG_SUCCESS : SSH_SMSG_FAILURE);
378: packet_send();
379: packet_write_wait();
380:
381: /* Enable compression now that we have replied if appropriate. */
382: if (enable_compression_after_reply) {
383: enable_compression_after_reply = 0;
384: packet_start_compression(compression_level);
385: }
386: }
387: }
388:
389: /*
390: * This is called to fork and execute a command when we have no tty. This
391: * will call do_child from the child, and server_loop from the parent after
392: * setting up file descriptors and such.
393: */
1.4 markus 394: void
1.63 markus 395: do_exec_no_pty(Session *s, const char *command)
1.1 markus 396: {
1.137 mpech 397: pid_t pid;
1.1 markus 398:
399: int inout[2], err[2];
400: /* Uses socket pairs to communicate with the program. */
401: if (socketpair(AF_UNIX, SOCK_STREAM, 0, inout) < 0 ||
402: socketpair(AF_UNIX, SOCK_STREAM, 0, err) < 0)
403: packet_disconnect("Could not create socket pairs: %.100s",
404: strerror(errno));
405: if (s == NULL)
406: fatal("do_exec_no_pty: no session");
407:
1.9 markus 408: session_proctitle(s);
1.1 markus 409:
410: /* Fork the child. */
411: if ((pid = fork()) == 0) {
1.165 markus 412: is_child = 1;
1.144 markus 413:
1.1 markus 414: /* Child. Reinitialize the log since the pid has changed. */
415: log_init(__progname, options.log_level, options.log_facility, log_stderr);
416:
417: /*
418: * Create a new session and process group since the 4.4BSD
419: * setlogin() affects the entire process group.
420: */
421: if (setsid() < 0)
422: error("setsid failed: %.100s", strerror(errno));
423:
424: /*
425: * Redirect stdin, stdout, and stderr. Stdin and stdout will
426: * use the same socket, as some programs (particularly rdist)
427: * seem to depend on it.
428: */
429: close(inout[1]);
430: close(err[1]);
431: if (dup2(inout[0], 0) < 0) /* stdin */
432: perror("dup2 stdin");
433: if (dup2(inout[0], 1) < 0) /* stdout. Note: same socket as stdin. */
434: perror("dup2 stdout");
435: if (dup2(err[0], 2) < 0) /* stderr */
436: perror("dup2 stderr");
437:
1.228 djm 438: closefrom(STDERR_FILENO + 1);
439:
1.1 markus 440: /* Do processing for the child (exec command etc). */
1.60 markus 441: do_child(s, command);
1.1 markus 442: /* NOTREACHED */
443: }
444: if (pid < 0)
445: packet_disconnect("fork failed: %.100s", strerror(errno));
446: s->pid = pid;
1.47 markus 447: /* Set interactive/non-interactive mode. */
1.48 markus 448: packet_set_interactive(s->display != NULL);
1.1 markus 449:
450: /* We are the parent. Close the child sides of the socket pairs. */
451: close(inout[0]);
452: close(err[0]);
453:
454: /*
455: * Enter the interactive session. Note: server_loop must be able to
456: * handle the case that fdin and fdout are the same.
457: */
1.2 markus 458: if (compat20) {
1.64 markus 459: session_set_fds(s, inout[1], inout[1], s->is_subsystem ? -1 : err[1]);
1.2 markus 460: } else {
461: server_loop(pid, inout[1], inout[1], err[1]);
462: /* server_loop has closed inout[1] and err[1]. */
463: }
1.1 markus 464: }
465:
466: /*
467: * This is called to fork and execute a command when we have a tty. This
468: * will call do_child from the child, and server_loop from the parent after
469: * setting up file descriptors, controlling tty, updating wtmp, utmp,
470: * lastlog, and other such operations.
471: */
1.4 markus 472: void
1.63 markus 473: do_exec_pty(Session *s, const char *command)
1.1 markus 474: {
475: int fdout, ptyfd, ttyfd, ptymaster;
476: pid_t pid;
477:
478: if (s == NULL)
479: fatal("do_exec_pty: no session");
480: ptyfd = s->ptyfd;
481: ttyfd = s->ttyfd;
482:
483: /* Fork the child. */
484: if ((pid = fork()) == 0) {
1.165 markus 485: is_child = 1;
1.97 markus 486:
1.24 markus 487: /* Child. Reinitialize the log because the pid has changed. */
1.1 markus 488: log_init(__progname, options.log_level, options.log_facility, log_stderr);
489: /* Close the master side of the pseudo tty. */
490: close(ptyfd);
491:
492: /* Make the pseudo tty our controlling tty. */
493: pty_make_controlling_tty(&ttyfd, s->tty);
494:
1.103 markus 495: /* Redirect stdin/stdout/stderr from the pseudo tty. */
496: if (dup2(ttyfd, 0) < 0)
497: error("dup2 stdin: %s", strerror(errno));
498: if (dup2(ttyfd, 1) < 0)
499: error("dup2 stdout: %s", strerror(errno));
500: if (dup2(ttyfd, 2) < 0)
501: error("dup2 stderr: %s", strerror(errno));
1.1 markus 502:
503: /* Close the extra descriptor for the pseudo tty. */
504: close(ttyfd);
505:
1.24 markus 506: /* record login, etc. similar to login(1) */
1.41 markus 507: if (!(options.use_login && command == NULL))
508: do_login(s, command);
1.228 djm 509:
510: closefrom(STDERR_FILENO + 1);
1.1 markus 511:
512: /* Do common processing for the child, such as execing the command. */
1.60 markus 513: do_child(s, command);
1.1 markus 514: /* NOTREACHED */
515: }
516: if (pid < 0)
517: packet_disconnect("fork failed: %.100s", strerror(errno));
518: s->pid = pid;
519:
520: /* Parent. Close the slave side of the pseudo tty. */
521: close(ttyfd);
522:
523: /*
524: * Create another descriptor of the pty master side for use as the
525: * standard input. We could use the original descriptor, but this
526: * simplifies code in server_loop. The descriptor is bidirectional.
527: */
528: fdout = dup(ptyfd);
529: if (fdout < 0)
530: packet_disconnect("dup #1 failed: %.100s", strerror(errno));
531:
532: /* we keep a reference to the pty master */
533: ptymaster = dup(ptyfd);
534: if (ptymaster < 0)
535: packet_disconnect("dup #2 failed: %.100s", strerror(errno));
536: s->ptymaster = ptymaster;
537:
538: /* Enter interactive session. */
1.47 markus 539: packet_set_interactive(1);
1.2 markus 540: if (compat20) {
541: session_set_fds(s, ptyfd, fdout, -1);
542: } else {
543: server_loop(pid, ptyfd, fdout, -1);
544: /* server_loop _has_ closed ptyfd and fdout. */
1.24 markus 545: }
546: }
547:
1.90 markus 548: /*
549: * This is called to fork and execute a command. If another command is
550: * to be forced, execute that instead.
551: */
552: void
553: do_exec(Session *s, const char *command)
554: {
1.210 dtucker 555: if (options.adm_forced_command) {
556: original_command = command;
557: command = options.adm_forced_command;
1.226 djm 558: if (strcmp(INTERNAL_SFTP_NAME, command) == 0)
559: s->is_subsystem = SUBSYSTEM_INT_SFTP;
560: else if (s->is_subsystem)
1.225 markus 561: s->is_subsystem = SUBSYSTEM_EXT;
1.210 dtucker 562: debug("Forced command (config) '%.900s'", command);
563: } else if (forced_command) {
1.90 markus 564: original_command = command;
565: command = forced_command;
1.226 djm 566: if (strcmp(INTERNAL_SFTP_NAME, command) == 0)
567: s->is_subsystem = SUBSYSTEM_INT_SFTP;
568: else if (s->is_subsystem)
1.225 markus 569: s->is_subsystem = SUBSYSTEM_EXT;
1.210 dtucker 570: debug("Forced command (key option) '%.900s'", command);
1.90 markus 571: }
1.163 markus 572:
573: #ifdef GSSAPI
574: if (options.gss_authentication) {
575: temporarily_use_uid(s->pw);
576: ssh_gssapi_storecreds();
577: restore_uid();
578: }
579: #endif
1.90 markus 580: if (s->ttyfd != -1)
581: do_exec_pty(s, command);
582: else
583: do_exec_no_pty(s, command);
584:
1.92 markus 585: original_command = NULL;
1.179 dtucker 586:
587: /*
588: * Clear loginmsg: it's the child's responsibility to display
589: * it to the user, otherwise multiple sessions may accumulate
590: * multiple copies of the login messages.
591: */
592: buffer_clear(&loginmsg);
1.90 markus 593: }
594:
595:
1.24 markus 596: /* administrative, login(1)-like work */
597: void
1.41 markus 598: do_login(Session *s, const char *command)
1.24 markus 599: {
600: socklen_t fromlen;
601: struct sockaddr_storage from;
602: struct passwd * pw = s->pw;
603: pid_t pid = getpid();
604:
605: /*
606: * Get IP address of client. If the connection is not a socket, let
607: * the address be 0.0.0.0.
608: */
609: memset(&from, 0, sizeof(from));
1.148 stevesk 610: fromlen = sizeof(from);
1.24 markus 611: if (packet_connection_is_on_socket()) {
612: if (getpeername(packet_get_connection_in(),
1.200 deraadt 613: (struct sockaddr *)&from, &fromlen) < 0) {
1.24 markus 614: debug("getpeername: %.100s", strerror(errno));
1.165 markus 615: cleanup_exit(255);
1.24 markus 616: }
617: }
1.25 markus 618:
1.24 markus 619: /* Record that there was a login on that tty from the remote host. */
1.133 markus 620: if (!use_privsep)
621: record_login(pid, s->tty, pw->pw_name, pw->pw_uid,
622: get_remote_name_or_ip(utmp_len,
1.158 markus 623: options.use_dns),
1.148 stevesk 624: (struct sockaddr *)&from, fromlen);
1.24 markus 625:
1.73 djm 626: if (check_quietlogin(s, command))
1.24 markus 627: return;
1.73 djm 628:
1.179 dtucker 629: display_loginmsg();
1.73 djm 630:
631: do_motd();
632: }
633:
634: /*
635: * Display the message of the day.
636: */
637: void
638: do_motd(void)
639: {
640: FILE *f;
641: char buf[256];
642:
1.24 markus 643: if (options.print_motd) {
1.28 millert 644: f = fopen(login_getcapstr(lc, "welcome", "/etc/motd",
645: "/etc/motd"), "r");
1.24 markus 646: if (f) {
647: while (fgets(buf, sizeof(buf), f))
648: fputs(buf, stdout);
649: fclose(f);
650: }
1.2 markus 651: }
1.73 djm 652: }
653:
654:
655: /*
656: * Check for quiet login, either .hushlogin or command given.
657: */
658: int
659: check_quietlogin(Session *s, const char *command)
660: {
661: char buf[256];
1.96 dugsong 662: struct passwd *pw = s->pw;
1.73 djm 663: struct stat st;
664:
665: /* Return 1 if .hushlogin exists or a command given. */
666: if (command != NULL)
667: return 1;
668: snprintf(buf, sizeof(buf), "%.200s/.hushlogin", pw->pw_dir);
669: if (login_getcapbool(lc, "hushlogin", 0) || stat(buf, &st) >= 0)
670: return 1;
671: return 0;
1.1 markus 672: }
673:
674: /*
675: * Sets the value of the given variable in the environment. If the variable
676: * already exists, its value is overriden.
677: */
1.161 markus 678: void
1.45 markus 679: child_set_env(char ***envp, u_int *envsizep, const char *name,
1.112 deraadt 680: const char *value)
1.1 markus 681: {
1.164 markus 682: char **env;
683: u_int envsize;
1.45 markus 684: u_int i, namelen;
1.1 markus 685:
686: /*
687: * Find the slot where the value should be stored. If the variable
688: * already exists, we reuse the slot; otherwise we append a new slot
689: * at the end of the array, expanding if necessary.
690: */
691: env = *envp;
692: namelen = strlen(name);
693: for (i = 0; env[i]; i++)
694: if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=')
695: break;
696: if (env[i]) {
697: /* Reuse the slot. */
698: xfree(env[i]);
699: } else {
700: /* New variable. Expand if necessary. */
1.164 markus 701: envsize = *envsizep;
702: if (i >= envsize - 1) {
703: if (envsize >= 1000)
704: fatal("child_set_env: too many env vars");
705: envsize += 50;
1.201 djm 706: env = (*envp) = xrealloc(env, envsize, sizeof(char *));
1.164 markus 707: *envsizep = envsize;
1.1 markus 708: }
709: /* Need to set the NULL pointer at end of array beyond the new slot. */
710: env[i + 1] = NULL;
711: }
712:
713: /* Allocate space and format the variable in the appropriate slot. */
714: env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1);
715: snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value);
716: }
717:
718: /*
719: * Reads environment variables from the given file and adds/overrides them
720: * into the environment. If the file does not exist, this does nothing.
721: * Otherwise, it must consist of empty lines, comments (line starts with '#')
722: * and assignments of the form name=value. No other forms are allowed.
723: */
1.94 itojun 724: static void
1.45 markus 725: read_environment_file(char ***env, u_int *envsize,
1.112 deraadt 726: const char *filename)
1.1 markus 727: {
728: FILE *f;
729: char buf[4096];
730: char *cp, *value;
1.142 deraadt 731: u_int lineno = 0;
1.1 markus 732:
733: f = fopen(filename, "r");
734: if (!f)
735: return;
736:
737: while (fgets(buf, sizeof(buf), f)) {
1.142 deraadt 738: if (++lineno > 1000)
739: fatal("Too many lines in environment file %s", filename);
1.1 markus 740: for (cp = buf; *cp == ' ' || *cp == '\t'; cp++)
741: ;
742: if (!*cp || *cp == '#' || *cp == '\n')
743: continue;
1.224 gilles 744:
745: cp[strcspn(cp, "\n")] = '\0';
746:
1.1 markus 747: value = strchr(cp, '=');
748: if (value == NULL) {
1.142 deraadt 749: fprintf(stderr, "Bad line %u in %.100s\n", lineno,
750: filename);
1.1 markus 751: continue;
752: }
1.14 deraadt 753: /*
754: * Replace the equals sign by nul, and advance value to
755: * the value string.
756: */
1.1 markus 757: *value = '\0';
758: value++;
759: child_set_env(env, envsize, cp, value);
760: }
761: fclose(f);
762: }
763:
1.127 markus 764: static char **
765: do_setup_env(Session *s, const char *shell)
1.1 markus 766: {
767: char buf[256];
1.127 markus 768: u_int i, envsize;
1.154 markus 769: char **env, *laddr;
1.127 markus 770: struct passwd *pw = s->pw;
1.1 markus 771:
772: /* Initialize the environment. */
773: envsize = 100;
1.220 djm 774: env = xcalloc(envsize, sizeof(char *));
1.1 markus 775: env[0] = NULL;
776:
1.161 markus 777: #ifdef GSSAPI
1.168 djm 778: /* Allow any GSSAPI methods that we've used to alter
1.161 markus 779: * the childs environment as they see fit
780: */
781: ssh_gssapi_do_child(&env, &envsize);
782: #endif
783:
1.1 markus 784: if (!options.use_login) {
785: /* Set basic environment. */
1.173 djm 786: for (i = 0; i < s->num_env; i++)
1.178 deraadt 787: child_set_env(&env, &envsize, s->env[i].name,
1.173 djm 788: s->env[i].val);
789:
1.1 markus 790: child_set_env(&env, &envsize, "USER", pw->pw_name);
791: child_set_env(&env, &envsize, "LOGNAME", pw->pw_name);
792: child_set_env(&env, &envsize, "HOME", pw->pw_dir);
1.145 markus 793: if (setusercontext(lc, pw, pw->pw_uid, LOGIN_SETPATH) < 0)
794: child_set_env(&env, &envsize, "PATH", _PATH_STDPATH);
795: else
796: child_set_env(&env, &envsize, "PATH", getenv("PATH"));
1.1 markus 797:
798: snprintf(buf, sizeof buf, "%.200s/%.50s",
799: _PATH_MAILDIR, pw->pw_name);
800: child_set_env(&env, &envsize, "MAIL", buf);
801:
802: /* Normal systems set SHELL by default. */
803: child_set_env(&env, &envsize, "SHELL", shell);
804: }
805: if (getenv("TZ"))
806: child_set_env(&env, &envsize, "TZ", getenv("TZ"));
807:
808: /* Set custom environment options from RSA authentication. */
1.110 markus 809: if (!options.use_login) {
810: while (custom_environment) {
811: struct envstring *ce = custom_environment;
1.143 deraadt 812: char *str = ce->s;
1.127 markus 813:
1.143 deraadt 814: for (i = 0; str[i] != '=' && str[i]; i++)
1.110 markus 815: ;
1.143 deraadt 816: if (str[i] == '=') {
817: str[i] = 0;
818: child_set_env(&env, &envsize, str, str + i + 1);
1.110 markus 819: }
820: custom_environment = ce->next;
821: xfree(ce->s);
822: xfree(ce);
1.1 markus 823: }
824: }
825:
1.149 stevesk 826: /* SSH_CLIENT deprecated */
1.1 markus 827: snprintf(buf, sizeof buf, "%.50s %d %d",
1.127 markus 828: get_remote_ipaddr(), get_remote_port(), get_local_port());
1.1 markus 829: child_set_env(&env, &envsize, "SSH_CLIENT", buf);
1.149 stevesk 830:
1.154 markus 831: laddr = get_local_ipaddr(packet_get_connection_in());
1.149 stevesk 832: snprintf(buf, sizeof buf, "%.50s %d %.50s %d",
1.154 markus 833: get_remote_ipaddr(), get_remote_port(), laddr, get_local_port());
834: xfree(laddr);
1.149 stevesk 835: child_set_env(&env, &envsize, "SSH_CONNECTION", buf);
1.1 markus 836:
1.60 markus 837: if (s->ttyfd != -1)
838: child_set_env(&env, &envsize, "SSH_TTY", s->tty);
839: if (s->term)
840: child_set_env(&env, &envsize, "TERM", s->term);
841: if (s->display)
842: child_set_env(&env, &envsize, "DISPLAY", s->display);
1.34 markus 843: if (original_command)
844: child_set_env(&env, &envsize, "SSH_ORIGINAL_COMMAND",
845: original_command);
1.96 dugsong 846: #ifdef KRB5
847: if (s->authctxt->krb5_ticket_file)
848: child_set_env(&env, &envsize, "KRB5CCNAME",
1.112 deraadt 849: s->authctxt->krb5_ticket_file);
1.96 dugsong 850: #endif
1.136 markus 851: if (auth_sock_name != NULL)
1.1 markus 852: child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME,
1.136 markus 853: auth_sock_name);
1.1 markus 854:
855: /* read $HOME/.ssh/environment. */
1.146 markus 856: if (options.permit_user_env && !options.use_login) {
1.14 deraadt 857: snprintf(buf, sizeof buf, "%.200s/.ssh/environment",
858: pw->pw_dir);
1.1 markus 859: read_environment_file(&env, &envsize, buf);
860: }
861: if (debug_flag) {
862: /* dump the environment */
863: fprintf(stderr, "Environment:\n");
864: for (i = 0; env[i]; i++)
865: fprintf(stderr, " %.200s\n", env[i]);
866: }
1.127 markus 867: return env;
868: }
869:
870: /*
871: * Run $HOME/.ssh/rc, /etc/ssh/sshrc, or xauth (whichever is found
872: * first in this order).
873: */
874: static void
875: do_rc_files(Session *s, const char *shell)
876: {
877: FILE *f = NULL;
878: char cmd[1024];
879: int do_xauth;
880: struct stat st;
881:
882: do_xauth =
883: s->display != NULL && s->auth_proto != NULL && s->auth_data != NULL;
884:
885: /* ignore _PATH_SSH_USER_RC for subsystems */
886: if (!s->is_subsystem && (stat(_PATH_SSH_USER_RC, &st) >= 0)) {
887: snprintf(cmd, sizeof cmd, "%s -c '%s %s'",
888: shell, _PATH_BSHELL, _PATH_SSH_USER_RC);
889: if (debug_flag)
890: fprintf(stderr, "Running %s\n", cmd);
891: f = popen(cmd, "w");
892: if (f) {
893: if (do_xauth)
894: fprintf(f, "%s %s\n", s->auth_proto,
895: s->auth_data);
896: pclose(f);
897: } else
898: fprintf(stderr, "Could not run %s\n",
899: _PATH_SSH_USER_RC);
900: } else if (stat(_PATH_SSH_SYSTEM_RC, &st) >= 0) {
901: if (debug_flag)
902: fprintf(stderr, "Running %s %s\n", _PATH_BSHELL,
903: _PATH_SSH_SYSTEM_RC);
904: f = popen(_PATH_BSHELL " " _PATH_SSH_SYSTEM_RC, "w");
905: if (f) {
906: if (do_xauth)
907: fprintf(f, "%s %s\n", s->auth_proto,
908: s->auth_data);
909: pclose(f);
910: } else
911: fprintf(stderr, "Could not run %s\n",
912: _PATH_SSH_SYSTEM_RC);
913: } else if (do_xauth && options.xauth_location != NULL) {
914: /* Add authority data to .Xauthority if appropriate. */
915: if (debug_flag) {
916: fprintf(stderr,
1.151 stevesk 917: "Running %.500s remove %.100s\n",
1.165 markus 918: options.xauth_location, s->auth_display);
1.151 stevesk 919: fprintf(stderr,
920: "%.500s add %.100s %.100s %.100s\n",
1.127 markus 921: options.xauth_location, s->auth_display,
922: s->auth_proto, s->auth_data);
923: }
924: snprintf(cmd, sizeof cmd, "%s -q -",
925: options.xauth_location);
926: f = popen(cmd, "w");
927: if (f) {
1.151 stevesk 928: fprintf(f, "remove %s\n",
929: s->auth_display);
1.127 markus 930: fprintf(f, "add %s %s %s\n",
931: s->auth_display, s->auth_proto,
932: s->auth_data);
933: pclose(f);
934: } else {
935: fprintf(stderr, "Could not run %s\n",
936: cmd);
937: }
938: }
939: }
940:
941: static void
942: do_nologin(struct passwd *pw)
943: {
944: FILE *f = NULL;
945: char buf[1024];
946:
947: if (!login_getcapbool(lc, "ignorenologin", 0) && pw->pw_uid)
948: f = fopen(login_getcapstr(lc, "nologin", _PATH_NOLOGIN,
949: _PATH_NOLOGIN), "r");
950: if (f) {
951: /* /etc/nologin exists. Print its contents and exit. */
1.155 itojun 952: logit("User %.100s not allowed because %s exists",
1.150 stevesk 953: pw->pw_name, _PATH_NOLOGIN);
1.127 markus 954: while (fgets(buf, sizeof(buf), f))
955: fputs(buf, stderr);
956: fclose(f);
957: exit(254);
958: }
959: }
960:
1.226 djm 961: /*
962: * Chroot into a directory after checking it for safety: all path components
963: * must be root-owned directories with strict permissions.
964: */
965: static void
966: safely_chroot(const char *path, uid_t uid)
967: {
968: const char *cp;
969: char component[MAXPATHLEN];
970: struct stat st;
971:
972: if (*path != '/')
973: fatal("chroot path does not begin at root");
974: if (strlen(path) >= sizeof(component))
975: fatal("chroot path too long");
976:
977: /*
978: * Descend the path, checking that each component is a
979: * root-owned directory with strict permissions.
980: */
981: for (cp = path; cp != NULL;) {
982: if ((cp = strchr(cp, '/')) == NULL)
983: strlcpy(component, path, sizeof(component));
984: else {
985: cp++;
986: memcpy(component, path, cp - path);
987: component[cp - path] = '\0';
988: }
989:
990: debug3("%s: checking '%s'", __func__, component);
991:
992: if (stat(component, &st) != 0)
993: fatal("%s: stat(\"%s\"): %s", __func__,
994: component, strerror(errno));
995: if (st.st_uid != 0 || (st.st_mode & 022) != 0)
996: fatal("bad ownership or modes for chroot "
997: "directory %s\"%s\"",
998: cp == NULL ? "" : "component ", component);
999: if (!S_ISDIR(st.st_mode))
1000: fatal("chroot path %s\"%s\" is not a directory",
1001: cp == NULL ? "" : "component ", component);
1002:
1003: }
1004:
1005: if (chdir(path) == -1)
1006: fatal("Unable to chdir to chroot path \"%s\": "
1007: "%s", path, strerror(errno));
1008: if (chroot(path) == -1)
1009: fatal("chroot(\"%s\"): %s", path, strerror(errno));
1010: if (chdir("/") == -1)
1011: fatal("%s: chdir(/) after chroot: %s",
1012: __func__, strerror(errno));
1013: verbose("Changed root directory to \"%s\"", path);
1014: }
1015:
1.127 markus 1016: /* Set login name, uid, gid, and groups. */
1.130 provos 1017: void
1.127 markus 1018: do_setusercontext(struct passwd *pw)
1019: {
1.227 djm 1020: char *chroot_path, *tmp;
1021:
1.127 markus 1022: if (getuid() == 0 || geteuid() == 0) {
1.226 djm 1023: /* Prepare groups */
1.127 markus 1024: if (setusercontext(lc, pw, pw->pw_uid,
1.226 djm 1025: (LOGIN_SETALL & ~(LOGIN_SETPATH|LOGIN_SETUSER))) < 0) {
1.127 markus 1026: perror("unable to set user context");
1027: exit(1);
1028: }
1.226 djm 1029:
1030: if (options.chroot_directory != NULL &&
1031: strcasecmp(options.chroot_directory, "none") != 0) {
1.227 djm 1032: tmp = tilde_expand_filename(options.chroot_directory,
1033: pw->pw_uid);
1034: chroot_path = percent_expand(tmp, "h", pw->pw_dir,
1035: "u", pw->pw_name, (char *)NULL);
1.226 djm 1036: safely_chroot(chroot_path, pw->pw_uid);
1.227 djm 1037: free(tmp);
1.226 djm 1038: free(chroot_path);
1039: }
1040:
1041: /* Set UID */
1042: if (setusercontext(lc, pw, pw->pw_uid, LOGIN_SETUSER) < 0) {
1043: perror("unable to set user context (setuser)");
1044: exit(1);
1045: }
1.127 markus 1046: }
1047: if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid)
1048: fatal("Failed to set uids to %u.", (u_int) pw->pw_uid);
1049: }
1050:
1.131 markus 1051: static void
1.172 markus 1052: do_pwchange(Session *s)
1053: {
1.179 dtucker 1054: fflush(NULL);
1.172 markus 1055: fprintf(stderr, "WARNING: Your password has expired.\n");
1056: if (s->ttyfd != -1) {
1.178 deraadt 1057: fprintf(stderr,
1.172 markus 1058: "You must change your password now and login again!\n");
1059: execl(_PATH_PASSWD_PROG, "passwd", (char *)NULL);
1060: perror("passwd");
1061: } else {
1062: fprintf(stderr,
1063: "Password change required but no TTY available.\n");
1064: }
1065: exit(1);
1066: }
1067:
1068: static void
1.130 provos 1069: launch_login(struct passwd *pw, const char *hostname)
1070: {
1071: /* Launch login(1). */
1072:
1073: execl("/usr/bin/login", "login", "-h", hostname,
1074: "-p", "-f", "--", pw->pw_name, (char *)NULL);
1075:
1076: /* Login couldn't be executed, die. */
1077:
1078: perror("login");
1079: exit(1);
1080: }
1081:
1.172 markus 1082: static void
1083: child_close_fds(void)
1084: {
1085: int i;
1086:
1087: if (packet_get_connection_in() == packet_get_connection_out())
1088: close(packet_get_connection_in());
1089: else {
1090: close(packet_get_connection_in());
1091: close(packet_get_connection_out());
1092: }
1093: /*
1094: * Close all descriptors related to channels. They will still remain
1095: * open in the parent.
1096: */
1097: /* XXX better use close-on-exec? -markus */
1098: channel_close_all();
1099:
1100: /*
1101: * Close any extra file descriptors. Note that there may still be
1102: * descriptors left by system functions. They will be closed later.
1103: */
1104: endpwent();
1105:
1106: /*
1.188 djm 1107: * Close any extra open file descriptors so that we don't have them
1.172 markus 1108: * hanging around in clients. Note that we want to do this after
1109: * initgroups, because at least on Solaris 2.3 it leaves file
1110: * descriptors open.
1111: */
1112: for (i = 3; i < 64; i++)
1113: close(i);
1114: }
1115:
1.127 markus 1116: /*
1117: * Performs common processing for the child, such as setting up the
1118: * environment, closing extra file descriptors, setting the user and group
1119: * ids, and executing the command or shell.
1120: */
1.225 markus 1121: #define ARGV_MAX 10
1.127 markus 1122: void
1123: do_child(Session *s, const char *command)
1124: {
1125: extern char **environ;
1126: char **env;
1.225 markus 1127: char *argv[ARGV_MAX];
1.127 markus 1128: const char *shell, *shell0, *hostname = NULL;
1129: struct passwd *pw = s->pw;
1130:
1131: /* remove hostkey from the child's memory */
1132: destroy_sensitive_data();
1133:
1.172 markus 1134: /* Force a password change */
1135: if (s->authctxt->force_pwchange) {
1136: do_setusercontext(pw);
1137: child_close_fds();
1138: do_pwchange(s);
1139: exit(1);
1140: }
1141:
1.127 markus 1142: /* login(1) is only called if we execute the login shell */
1143: if (options.use_login && command != NULL)
1144: options.use_login = 0;
1145:
1146: /*
1147: * Login(1) does this as well, and it needs uid 0 for the "-h"
1148: * switch, so we let login(1) to this for us.
1149: */
1150: if (!options.use_login) {
1151: do_nologin(pw);
1152: do_setusercontext(pw);
1153: }
1154:
1155: /*
1156: * Get the shell from the password data. An empty shell field is
1157: * legal, and means /bin/sh.
1158: */
1159: shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
1.152 markus 1160:
1161: /*
1162: * Make sure $SHELL points to the shell from the password file,
1163: * even if shell is overridden from login.conf
1164: */
1165: env = do_setup_env(s, shell);
1166:
1.127 markus 1167: shell = login_getcapstr(lc, "shell", (char *)shell, (char *)shell);
1168:
1.26 millert 1169: /* we have to stash the hostname before we close our socket. */
1170: if (options.use_login)
1.70 stevesk 1171: hostname = get_remote_name_or_ip(utmp_len,
1.158 markus 1172: options.use_dns);
1.1 markus 1173: /*
1174: * Close the connection descriptors; note that this is the child, and
1175: * the server will still have the socket open, and it is important
1176: * that we do not shutdown it. Note that the descriptors cannot be
1177: * closed before building the environment, as we call
1178: * get_remote_ipaddr there.
1179: */
1.172 markus 1180: child_close_fds();
1.1 markus 1181:
1182: /*
1.125 deraadt 1183: * Must take new environment into use so that .ssh/rc,
1184: * /etc/ssh/sshrc and xauth are run in the proper environment.
1.1 markus 1185: */
1186: environ = env;
1.170 jakob 1187:
1188: #ifdef KRB5
1189: /*
1190: * At this point, we check to see if AFS is active and if we have
1191: * a valid Kerberos 5 TGT. If so, it seems like a good idea to see
1192: * if we can (and need to) extend the ticket into an AFS token. If
1193: * we don't do this, we run into potential problems if the user's
1194: * home directory is in AFS and it's not world-readable.
1195: */
1196:
1197: if (options.kerberos_get_afs_token && k_hasafs() &&
1.185 djm 1198: (s->authctxt->krb5_ctx != NULL)) {
1.170 jakob 1199: char cell[64];
1200:
1201: debug("Getting AFS token");
1202:
1203: k_setpag();
1204:
1205: if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0)
1206: krb5_afslog(s->authctxt->krb5_ctx,
1207: s->authctxt->krb5_fwd_ccache, cell, NULL);
1208:
1209: krb5_afslog_home(s->authctxt->krb5_ctx,
1210: s->authctxt->krb5_fwd_ccache, NULL, NULL, pw->pw_dir);
1211: }
1212: #endif
1.104 markus 1213:
1.188 djm 1214: /* Change current directory to the user's home directory. */
1.104 markus 1215: if (chdir(pw->pw_dir) < 0) {
1216: fprintf(stderr, "Could not chdir to home directory %s: %s\n",
1217: pw->pw_dir, strerror(errno));
1218: if (login_getcapbool(lc, "requirehome", 0))
1219: exit(1);
1220: }
1.1 markus 1221:
1.127 markus 1222: if (!options.use_login)
1223: do_rc_files(s, shell);
1.67 markus 1224:
1225: /* restore SIGPIPE for child */
1.217 stevesk 1226: signal(SIGPIPE, SIG_DFL);
1.67 markus 1227:
1.225 markus 1228: if (s->is_subsystem == SUBSYSTEM_INT_SFTP) {
1229: extern int optind, optreset;
1230: int i;
1231: char *p, *args;
1232:
1233: setproctitle("%s@internal-sftp-server", s->pw->pw_name);
1234: args = strdup(command ? command : "sftp-server");
1235: for (i = 0, (p = strtok(args, " ")); p; (p = strtok(NULL, " ")))
1236: if (i < ARGV_MAX - 1)
1237: argv[i++] = p;
1238: argv[i] = NULL;
1239: optind = optreset = 1;
1240: __progname = argv[0];
1.226 djm 1241: exit(sftp_server_main(i, argv, s->pw));
1.225 markus 1242: }
1243:
1.127 markus 1244: if (options.use_login) {
1.130 provos 1245: launch_login(pw, hostname);
1246: /* NEVERREACHED */
1.127 markus 1247: }
1248:
1249: /* Get the last component of the shell name. */
1250: if ((shell0 = strrchr(shell, '/')) != NULL)
1251: shell0++;
1252: else
1253: shell0 = shell;
1254:
1.1 markus 1255: /*
1256: * If we have no command, execute the shell. In this case, the shell
1257: * name to be passed in argv[0] is preceded by '-' to indicate that
1258: * this is a login shell.
1259: */
1260: if (!command) {
1.127 markus 1261: char argv0[256];
1.1 markus 1262:
1.127 markus 1263: /* Start the shell. Set initial character to '-'. */
1264: argv0[0] = '-';
1.1 markus 1265:
1.127 markus 1266: if (strlcpy(argv0 + 1, shell0, sizeof(argv0) - 1)
1.128 markus 1267: >= sizeof(argv0) - 1) {
1.127 markus 1268: errno = EINVAL;
1.1 markus 1269: perror(shell);
1270: exit(1);
1.127 markus 1271: }
1.1 markus 1272:
1.127 markus 1273: /* Execute the shell. */
1274: argv[0] = argv0;
1275: argv[1] = NULL;
1276: execve(shell, argv, env);
1277:
1278: /* Executing the shell failed. */
1279: perror(shell);
1280: exit(1);
1.1 markus 1281: }
1282: /*
1283: * Execute the command using the user's shell. This uses the -c
1284: * option to execute the command.
1285: */
1.127 markus 1286: argv[0] = (char *) shell0;
1.1 markus 1287: argv[1] = "-c";
1288: argv[2] = (char *) command;
1289: argv[3] = NULL;
1290: execve(shell, argv, env);
1291: perror(shell);
1292: exit(1);
1293: }
1294:
1295: Session *
1296: session_new(void)
1297: {
1298: int i;
1299: static int did_init = 0;
1300: if (!did_init) {
1301: debug("session_new: init");
1.112 deraadt 1302: for (i = 0; i < MAX_SESSIONS; i++) {
1.1 markus 1303: sessions[i].used = 0;
1304: }
1305: did_init = 1;
1306: }
1.112 deraadt 1307: for (i = 0; i < MAX_SESSIONS; i++) {
1.1 markus 1308: Session *s = &sessions[i];
1309: if (! s->used) {
1.68 djm 1310: memset(s, 0, sizeof(*s));
1.1 markus 1311: s->chanid = -1;
1312: s->ptyfd = -1;
1313: s->ttyfd = -1;
1314: s->used = 1;
1.85 markus 1315: s->self = i;
1.184 djm 1316: s->x11_chanids = NULL;
1.1 markus 1317: debug("session_new: session %d", i);
1318: return s;
1319: }
1320: }
1321: return NULL;
1322: }
1323:
1.94 itojun 1324: static void
1.1 markus 1325: session_dump(void)
1326: {
1327: int i;
1.112 deraadt 1328: for (i = 0; i < MAX_SESSIONS; i++) {
1.1 markus 1329: Session *s = &sessions[i];
1.137 mpech 1330: debug("dump: used %d session %d %p channel %d pid %ld",
1.1 markus 1331: s->used,
1332: s->self,
1333: s,
1334: s->chanid,
1.137 mpech 1335: (long)s->pid);
1.1 markus 1336: }
1337: }
1338:
1.2 markus 1339: int
1.97 markus 1340: session_open(Authctxt *authctxt, int chanid)
1.2 markus 1341: {
1342: Session *s = session_new();
1343: debug("session_open: channel %d", chanid);
1344: if (s == NULL) {
1345: error("no more sessions");
1346: return 0;
1347: }
1.97 markus 1348: s->authctxt = authctxt;
1349: s->pw = authctxt->pw;
1.167 djm 1350: if (s->pw == NULL || !authctxt->valid)
1.54 stevesk 1351: fatal("no user for session %d", s->self);
1.2 markus 1352: debug("session_open: session %d: link with channel %d", s->self, chanid);
1353: s->chanid = chanid;
1354: return 1;
1355: }
1356:
1.130 provos 1357: Session *
1358: session_by_tty(char *tty)
1359: {
1360: int i;
1361: for (i = 0; i < MAX_SESSIONS; i++) {
1362: Session *s = &sessions[i];
1363: if (s->used && s->ttyfd != -1 && strcmp(s->tty, tty) == 0) {
1364: debug("session_by_tty: session %d tty %s", i, tty);
1365: return s;
1366: }
1367: }
1368: debug("session_by_tty: unknown tty %.100s", tty);
1369: session_dump();
1370: return NULL;
1371: }
1372:
1.94 itojun 1373: static Session *
1.2 markus 1374: session_by_channel(int id)
1375: {
1376: int i;
1.112 deraadt 1377: for (i = 0; i < MAX_SESSIONS; i++) {
1.2 markus 1378: Session *s = &sessions[i];
1379: if (s->used && s->chanid == id) {
1380: debug("session_by_channel: session %d channel %d", i, id);
1381: return s;
1382: }
1383: }
1384: debug("session_by_channel: unknown channel %d", id);
1385: session_dump();
1386: return NULL;
1387: }
1388:
1.94 itojun 1389: static Session *
1.184 djm 1390: session_by_x11_channel(int id)
1391: {
1392: int i, j;
1393:
1394: for (i = 0; i < MAX_SESSIONS; i++) {
1395: Session *s = &sessions[i];
1396:
1397: if (s->x11_chanids == NULL || !s->used)
1398: continue;
1399: for (j = 0; s->x11_chanids[j] != -1; j++) {
1400: if (s->x11_chanids[j] == id) {
1401: debug("session_by_x11_channel: session %d "
1402: "channel %d", s->self, id);
1403: return s;
1404: }
1405: }
1406: }
1407: debug("session_by_x11_channel: unknown channel %d", id);
1408: session_dump();
1409: return NULL;
1410: }
1411:
1412: static Session *
1.2 markus 1413: session_by_pid(pid_t pid)
1414: {
1415: int i;
1.137 mpech 1416: debug("session_by_pid: pid %ld", (long)pid);
1.112 deraadt 1417: for (i = 0; i < MAX_SESSIONS; i++) {
1.2 markus 1418: Session *s = &sessions[i];
1419: if (s->used && s->pid == pid)
1420: return s;
1421: }
1.137 mpech 1422: error("session_by_pid: unknown pid %ld", (long)pid);
1.2 markus 1423: session_dump();
1424: return NULL;
1425: }
1426:
1.94 itojun 1427: static int
1.2 markus 1428: session_window_change_req(Session *s)
1429: {
1430: s->col = packet_get_int();
1431: s->row = packet_get_int();
1432: s->xpixel = packet_get_int();
1433: s->ypixel = packet_get_int();
1.116 markus 1434: packet_check_eom();
1.2 markus 1435: pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1436: return 1;
1437: }
1438:
1.94 itojun 1439: static int
1.2 markus 1440: session_pty_req(Session *s)
1441: {
1.45 markus 1442: u_int len;
1.72 stevesk 1443: int n_bytes;
1.132 markus 1444:
1.86 markus 1445: if (no_pty_flag) {
1446: debug("Allocating a pty not permitted for this authentication.");
1.19 markus 1447: return 0;
1.86 markus 1448: }
1449: if (s->ttyfd != -1) {
1450: packet_disconnect("Protocol error: you already have a pty.");
1.3 markus 1451: return 0;
1.86 markus 1452: }
1453:
1.2 markus 1454: s->term = packet_get_string(&len);
1.86 markus 1455:
1456: if (compat20) {
1457: s->col = packet_get_int();
1458: s->row = packet_get_int();
1459: } else {
1460: s->row = packet_get_int();
1461: s->col = packet_get_int();
1462: }
1.2 markus 1463: s->xpixel = packet_get_int();
1464: s->ypixel = packet_get_int();
1465:
1466: if (strcmp(s->term, "") == 0) {
1467: xfree(s->term);
1468: s->term = NULL;
1469: }
1.86 markus 1470:
1.2 markus 1471: /* Allocate a pty and open it. */
1.86 markus 1472: debug("Allocating pty.");
1.130 provos 1473: if (!PRIVSEP(pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty)))) {
1.86 markus 1474: if (s->term)
1475: xfree(s->term);
1.2 markus 1476: s->term = NULL;
1477: s->ptyfd = -1;
1478: s->ttyfd = -1;
1479: error("session_pty_req: session %d alloc failed", s->self);
1.3 markus 1480: return 0;
1.2 markus 1481: }
1482: debug("session_pty_req: session %d alloc %s", s->self, s->tty);
1.86 markus 1483:
1484: /* for SSH1 the tty modes length is not given */
1485: if (!compat20)
1486: n_bytes = packet_remaining();
1487: tty_parse_modes(s->ttyfd, &n_bytes);
1488:
1.130 provos 1489: if (!use_privsep)
1490: pty_setowner(s->pw, s->tty);
1.86 markus 1491:
1492: /* Set window size from the packet. */
1.2 markus 1493: pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
1494:
1.116 markus 1495: packet_check_eom();
1.9 markus 1496: session_proctitle(s);
1.2 markus 1497: return 1;
1498: }
1499:
1.94 itojun 1500: static int
1.7 markus 1501: session_subsystem_req(Session *s)
1502: {
1.105 markus 1503: struct stat st;
1.45 markus 1504: u_int len;
1.7 markus 1505: int success = 0;
1.205 djm 1506: char *prog, *cmd, *subsys = packet_get_string(&len);
1.182 djm 1507: u_int i;
1.7 markus 1508:
1.116 markus 1509: packet_check_eom();
1.155 itojun 1510: logit("subsystem request for %.100s", subsys);
1.18 jakob 1511:
1512: for (i = 0; i < options.num_subsystems; i++) {
1.105 markus 1513: if (strcmp(subsys, options.subsystem_name[i]) == 0) {
1.205 djm 1514: prog = options.subsystem_command[i];
1515: cmd = options.subsystem_args[i];
1.226 djm 1516: if (!strcmp(INTERNAL_SFTP_NAME, prog)) {
1.225 markus 1517: s->is_subsystem = SUBSYSTEM_INT_SFTP;
1518: } else if (stat(prog, &st) < 0) {
1.205 djm 1519: error("subsystem: cannot stat %s: %s", prog,
1.105 markus 1520: strerror(errno));
1521: break;
1.225 markus 1522: } else {
1523: s->is_subsystem = SUBSYSTEM_EXT;
1.105 markus 1524: }
1525: debug("subsystem: exec() %s", cmd);
1526: do_exec(s, cmd);
1.18 jakob 1527: success = 1;
1.122 markus 1528: break;
1.18 jakob 1529: }
1530: }
1531:
1532: if (!success)
1.155 itojun 1533: logit("subsystem request for %.100s failed, subsystem not found",
1.105 markus 1534: subsys);
1.7 markus 1535:
1536: xfree(subsys);
1537: return success;
1538: }
1539:
1.94 itojun 1540: static int
1.7 markus 1541: session_x11_req(Session *s)
1542: {
1.81 markus 1543: int success;
1.7 markus 1544:
1.184 djm 1545: if (s->auth_proto != NULL || s->auth_data != NULL) {
1546: error("session_x11_req: session %d: "
1.190 stevesk 1547: "x11 forwarding already active", s->self);
1.184 djm 1548: return 0;
1549: }
1.7 markus 1550: s->single_connection = packet_get_char();
1551: s->auth_proto = packet_get_string(NULL);
1552: s->auth_data = packet_get_string(NULL);
1553: s->screen = packet_get_int();
1.116 markus 1554: packet_check_eom();
1.7 markus 1555:
1.81 markus 1556: success = session_setup_x11fwd(s);
1557: if (!success) {
1.7 markus 1558: xfree(s->auth_proto);
1559: xfree(s->auth_data);
1.84 markus 1560: s->auth_proto = NULL;
1561: s->auth_data = NULL;
1.7 markus 1562: }
1.81 markus 1563: return success;
1.7 markus 1564: }
1565:
1.94 itojun 1566: static int
1.19 markus 1567: session_shell_req(Session *s)
1568: {
1.116 markus 1569: packet_check_eom();
1.90 markus 1570: do_exec(s, NULL);
1.19 markus 1571: return 1;
1572: }
1573:
1.94 itojun 1574: static int
1.19 markus 1575: session_exec_req(Session *s)
1576: {
1.45 markus 1577: u_int len;
1.19 markus 1578: char *command = packet_get_string(&len);
1.116 markus 1579: packet_check_eom();
1.90 markus 1580: do_exec(s, command);
1.92 markus 1581: xfree(command);
1.19 markus 1582: return 1;
1583: }
1584:
1.94 itojun 1585: static int
1.157 markus 1586: session_break_req(Session *s)
1587: {
1588:
1.175 deraadt 1589: packet_get_int(); /* ignored */
1.157 markus 1590: packet_check_eom();
1591:
1.160 markus 1592: if (s->ttyfd == -1 ||
1593: tcsendbreak(s->ttyfd, 0) < 0)
1.157 markus 1594: return 0;
1595: return 1;
1596: }
1597:
1598: static int
1.173 djm 1599: session_env_req(Session *s)
1600: {
1601: char *name, *val;
1602: u_int name_len, val_len, i;
1603:
1604: name = packet_get_string(&name_len);
1605: val = packet_get_string(&val_len);
1606: packet_check_eom();
1607:
1608: /* Don't set too many environment variables */
1609: if (s->num_env > 128) {
1610: debug2("Ignoring env request %s: too many env vars", name);
1611: goto fail;
1612: }
1613:
1614: for (i = 0; i < options.num_accept_env; i++) {
1615: if (match_pattern(name, options.accept_env[i])) {
1616: debug2("Setting env %d: %s=%s", s->num_env, name, val);
1.201 djm 1617: s->env = xrealloc(s->env, s->num_env + 1,
1618: sizeof(*s->env));
1.173 djm 1619: s->env[s->num_env].name = name;
1620: s->env[s->num_env].val = val;
1621: s->num_env++;
1622: return (1);
1623: }
1624: }
1625: debug2("Ignoring env request %s: disallowed name", name);
1626:
1627: fail:
1628: xfree(name);
1629: xfree(val);
1630: return (0);
1631: }
1632:
1633: static int
1.43 markus 1634: session_auth_agent_req(Session *s)
1635: {
1636: static int called = 0;
1.116 markus 1637: packet_check_eom();
1.44 markus 1638: if (no_agent_forwarding_flag) {
1639: debug("session_auth_agent_req: no_agent_forwarding_flag");
1640: return 0;
1641: }
1.43 markus 1642: if (called) {
1643: return 0;
1644: } else {
1645: called = 1;
1646: return auth_input_request_forwarding(s->pw);
1647: }
1648: }
1649:
1.123 markus 1650: int
1651: session_input_channel_req(Channel *c, const char *rtype)
1.2 markus 1652: {
1653: int success = 0;
1654: Session *s;
1655:
1.123 markus 1656: if ((s = session_by_channel(c->self)) == NULL) {
1.155 itojun 1657: logit("session_input_channel_req: no session %d req %.100s",
1.123 markus 1658: c->self, rtype);
1659: return 0;
1660: }
1661: debug("session_input_channel_req: session %d req %s", s->self, rtype);
1.2 markus 1662:
1663: /*
1.64 markus 1664: * a session is in LARVAL state until a shell, a command
1665: * or a subsystem is executed
1.2 markus 1666: */
1667: if (c->type == SSH_CHANNEL_LARVAL) {
1668: if (strcmp(rtype, "shell") == 0) {
1.19 markus 1669: success = session_shell_req(s);
1.2 markus 1670: } else if (strcmp(rtype, "exec") == 0) {
1.19 markus 1671: success = session_exec_req(s);
1.2 markus 1672: } else if (strcmp(rtype, "pty-req") == 0) {
1.221 stevesk 1673: success = session_pty_req(s);
1.7 markus 1674: } else if (strcmp(rtype, "x11-req") == 0) {
1675: success = session_x11_req(s);
1.43 markus 1676: } else if (strcmp(rtype, "auth-agent-req@openssh.com") == 0) {
1677: success = session_auth_agent_req(s);
1.7 markus 1678: } else if (strcmp(rtype, "subsystem") == 0) {
1679: success = session_subsystem_req(s);
1.173 djm 1680: } else if (strcmp(rtype, "env") == 0) {
1681: success = session_env_req(s);
1.2 markus 1682: }
1683: }
1684: if (strcmp(rtype, "window-change") == 0) {
1685: success = session_window_change_req(s);
1.177 djm 1686: } else if (strcmp(rtype, "break") == 0) {
1687: success = session_break_req(s);
1.2 markus 1688: }
1.177 djm 1689:
1.123 markus 1690: return success;
1.2 markus 1691: }
1692:
1693: void
1694: session_set_fds(Session *s, int fdin, int fdout, int fderr)
1695: {
1696: if (!compat20)
1697: fatal("session_set_fds: called for proto != 2.0");
1698: /*
1699: * now that have a child and a pipe to the child,
1700: * we can activate our channel and register the fd's
1701: */
1702: if (s->chanid == -1)
1703: fatal("no channel for session %d", s->self);
1704: channel_set_fds(s->chanid,
1705: fdout, fdin, fderr,
1.42 markus 1706: fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ,
1.126 markus 1707: 1,
1708: CHAN_SES_WINDOW_DEFAULT);
1.2 markus 1709: }
1710:
1.85 markus 1711: /*
1712: * Function to perform pty cleanup. Also called if we get aborted abnormally
1713: * (e.g., due to a dropped connection).
1714: */
1.130 provos 1715: void
1.165 markus 1716: session_pty_cleanup2(Session *s)
1.1 markus 1717: {
1.85 markus 1718: if (s == NULL) {
1719: error("session_pty_cleanup: no session");
1720: return;
1721: }
1722: if (s->ttyfd == -1)
1.1 markus 1723: return;
1724:
1.54 stevesk 1725: debug("session_pty_cleanup: session %d release %s", s->self, s->tty);
1.1 markus 1726:
1727: /* Record that the user has logged out. */
1.85 markus 1728: if (s->pid != 0)
1729: record_logout(s->pid, s->tty);
1.1 markus 1730:
1731: /* Release the pseudo-tty. */
1.130 provos 1732: if (getuid() == 0)
1733: pty_release(s->tty);
1.1 markus 1734:
1735: /*
1736: * Close the server side of the socket pairs. We must do this after
1737: * the pty cleanup, so that another process doesn't get this pty
1738: * while we're still cleaning up.
1739: */
1740: if (close(s->ptymaster) < 0)
1.130 provos 1741: error("close(s->ptymaster/%d): %s", s->ptymaster, strerror(errno));
1.108 markus 1742:
1743: /* unlink pty from session */
1744: s->ttyfd = -1;
1.2 markus 1745: }
1746:
1.130 provos 1747: void
1.165 markus 1748: session_pty_cleanup(Session *s)
1.130 provos 1749: {
1.165 markus 1750: PRIVSEP(session_pty_cleanup2(s));
1.130 provos 1751: }
1752:
1.147 markus 1753: static char *
1754: sig2name(int sig)
1755: {
1756: #define SSH_SIG(x) if (sig == SIG ## x) return #x
1757: SSH_SIG(ABRT);
1758: SSH_SIG(ALRM);
1759: SSH_SIG(FPE);
1760: SSH_SIG(HUP);
1761: SSH_SIG(ILL);
1762: SSH_SIG(INT);
1763: SSH_SIG(KILL);
1764: SSH_SIG(PIPE);
1765: SSH_SIG(QUIT);
1766: SSH_SIG(SEGV);
1767: SSH_SIG(TERM);
1768: SSH_SIG(USR1);
1769: SSH_SIG(USR2);
1770: #undef SSH_SIG
1771: return "SIG@openssh.com";
1772: }
1773:
1.94 itojun 1774: static void
1.184 djm 1775: session_close_x11(int id)
1776: {
1777: Channel *c;
1778:
1.189 markus 1779: if ((c = channel_by_id(id)) == NULL) {
1.184 djm 1780: debug("session_close_x11: x11 channel %d missing", id);
1781: } else {
1782: /* Detach X11 listener */
1783: debug("session_close_x11: detach x11 channel %d", id);
1784: channel_cancel_cleanup(id);
1785: if (c->ostate != CHAN_OUTPUT_CLOSED)
1786: chan_mark_dead(c);
1787: }
1788: }
1789:
1790: static void
1791: session_close_single_x11(int id, void *arg)
1792: {
1793: Session *s;
1794: u_int i;
1795:
1796: debug3("session_close_single_x11: channel %d", id);
1797: channel_cancel_cleanup(id);
1.221 stevesk 1798: if ((s = session_by_x11_channel(id)) == NULL)
1.184 djm 1799: fatal("session_close_single_x11: no x11 channel %d", id);
1800: for (i = 0; s->x11_chanids[i] != -1; i++) {
1801: debug("session_close_single_x11: session %d: "
1802: "closing channel %d", s->self, s->x11_chanids[i]);
1803: /*
1804: * The channel "id" is already closing, but make sure we
1805: * close all of its siblings.
1806: */
1807: if (s->x11_chanids[i] != id)
1808: session_close_x11(s->x11_chanids[i]);
1809: }
1810: xfree(s->x11_chanids);
1811: s->x11_chanids = NULL;
1812: if (s->display) {
1813: xfree(s->display);
1814: s->display = NULL;
1815: }
1816: if (s->auth_proto) {
1817: xfree(s->auth_proto);
1818: s->auth_proto = NULL;
1819: }
1820: if (s->auth_data) {
1821: xfree(s->auth_data);
1822: s->auth_data = NULL;
1823: }
1824: if (s->auth_display) {
1825: xfree(s->auth_display);
1826: s->auth_display = NULL;
1827: }
1828: }
1829:
1830: static void
1.2 markus 1831: session_exit_message(Session *s, int status)
1832: {
1833: Channel *c;
1.124 markus 1834:
1835: if ((c = channel_lookup(s->chanid)) == NULL)
1.85 markus 1836: fatal("session_exit_message: session %d: no channel %d",
1.2 markus 1837: s->self, s->chanid);
1.137 mpech 1838: debug("session_exit_message: session %d channel %d pid %ld",
1839: s->self, s->chanid, (long)s->pid);
1.2 markus 1840:
1841: if (WIFEXITED(status)) {
1.124 markus 1842: channel_request_start(s->chanid, "exit-status", 0);
1.2 markus 1843: packet_put_int(WEXITSTATUS(status));
1844: packet_send();
1845: } else if (WIFSIGNALED(status)) {
1.124 markus 1846: channel_request_start(s->chanid, "exit-signal", 0);
1.147 markus 1847: packet_put_cstring(sig2name(WTERMSIG(status)));
1.229 ! markus 1848: packet_put_char(WCOREDUMP(status)? 1 : 0);
1.2 markus 1849: packet_put_cstring("");
1850: packet_put_cstring("");
1851: packet_send();
1852: } else {
1853: /* Some weird exit cause. Just exit. */
1854: packet_disconnect("wait returned status %04x.", status);
1855: }
1856:
1857: /* disconnect channel */
1858: debug("session_exit_message: release channel %d", s->chanid);
1.187 djm 1859:
1860: /*
1861: * Adjust cleanup callback attachment to send close messages when
1.199 deraadt 1862: * the channel gets EOF. The session will be then be closed
1.187 djm 1863: * by session_close_by_channel when the childs close their fds.
1864: */
1865: channel_register_cleanup(c->self, session_close_by_channel, 1);
1866:
1.5 markus 1867: /*
1868: * emulate a write failure with 'chan_write_failed', nobody will be
1869: * interested in data we write.
1870: * Note that we must not call 'chan_read_failed', since there could
1871: * be some more data waiting in the pipe.
1872: */
1.8 markus 1873: if (c->ostate != CHAN_OUTPUT_CLOSED)
1874: chan_write_failed(c);
1.2 markus 1875: }
1876:
1.130 provos 1877: void
1.85 markus 1878: session_close(Session *s)
1.2 markus 1879: {
1.182 djm 1880: u_int i;
1.173 djm 1881:
1.137 mpech 1882: debug("session_close: session %d pid %ld", s->self, (long)s->pid);
1.165 markus 1883: if (s->ttyfd != -1)
1.85 markus 1884: session_pty_cleanup(s);
1.2 markus 1885: if (s->term)
1886: xfree(s->term);
1887: if (s->display)
1888: xfree(s->display);
1.184 djm 1889: if (s->x11_chanids)
1890: xfree(s->x11_chanids);
1.118 stevesk 1891: if (s->auth_display)
1892: xfree(s->auth_display);
1.2 markus 1893: if (s->auth_data)
1894: xfree(s->auth_data);
1895: if (s->auth_proto)
1896: xfree(s->auth_proto);
1897: s->used = 0;
1.219 djm 1898: if (s->env != NULL) {
1899: for (i = 0; i < s->num_env; i++) {
1900: xfree(s->env[i].name);
1901: xfree(s->env[i].val);
1902: }
1903: xfree(s->env);
1.173 djm 1904: }
1.9 markus 1905: session_proctitle(s);
1.2 markus 1906: }
1907:
1908: void
1909: session_close_by_pid(pid_t pid, int status)
1910: {
1911: Session *s = session_by_pid(pid);
1912: if (s == NULL) {
1.137 mpech 1913: debug("session_close_by_pid: no session for pid %ld",
1914: (long)pid);
1.2 markus 1915: return;
1916: }
1917: if (s->chanid != -1)
1918: session_exit_message(s, status);
1.187 djm 1919: if (s->ttyfd != -1)
1920: session_pty_cleanup(s);
1.197 djm 1921: s->pid = 0;
1.98 markus 1922: }
1923:
1.2 markus 1924: /*
1925: * this is called when a channel dies before
1926: * the session 'child' itself dies
1927: */
1928: void
1929: session_close_by_channel(int id, void *arg)
1930: {
1931: Session *s = session_by_channel(id);
1.187 djm 1932: u_int i;
1.184 djm 1933:
1.2 markus 1934: if (s == NULL) {
1.107 markus 1935: debug("session_close_by_channel: no session for id %d", id);
1.2 markus 1936: return;
1937: }
1.137 mpech 1938: debug("session_close_by_channel: channel %d child %ld",
1939: id, (long)s->pid);
1.107 markus 1940: if (s->pid != 0) {
1941: debug("session_close_by_channel: channel %d: has child", id);
1.108 markus 1942: /*
1943: * delay detach of session, but release pty, since
1944: * the fd's to the child are already closed
1945: */
1.165 markus 1946: if (s->ttyfd != -1)
1.108 markus 1947: session_pty_cleanup(s);
1.107 markus 1948: return;
1949: }
1950: /* detach by removing callback */
1.2 markus 1951: channel_cancel_cleanup(s->chanid);
1.187 djm 1952:
1953: /* Close any X11 listeners associated with this session */
1954: if (s->x11_chanids != NULL) {
1955: for (i = 0; s->x11_chanids[i] != -1; i++) {
1956: session_close_x11(s->x11_chanids[i]);
1957: s->x11_chanids[i] = -1;
1958: }
1959: }
1960:
1.2 markus 1961: s->chanid = -1;
1.106 markus 1962: session_close(s);
1963: }
1964:
1965: void
1.130 provos 1966: session_destroy_all(void (*closefunc)(Session *))
1.106 markus 1967: {
1968: int i;
1.112 deraadt 1969: for (i = 0; i < MAX_SESSIONS; i++) {
1.106 markus 1970: Session *s = &sessions[i];
1.130 provos 1971: if (s->used) {
1972: if (closefunc != NULL)
1973: closefunc(s);
1974: else
1975: session_close(s);
1976: }
1.2 markus 1977: }
1.9 markus 1978: }
1979:
1.94 itojun 1980: static char *
1.9 markus 1981: session_tty_list(void)
1982: {
1983: static char buf[1024];
1984: int i;
1985: buf[0] = '\0';
1.112 deraadt 1986: for (i = 0; i < MAX_SESSIONS; i++) {
1.9 markus 1987: Session *s = &sessions[i];
1988: if (s->used && s->ttyfd != -1) {
1989: if (buf[0] != '\0')
1990: strlcat(buf, ",", sizeof buf);
1991: strlcat(buf, strrchr(s->tty, '/') + 1, sizeof buf);
1992: }
1993: }
1994: if (buf[0] == '\0')
1995: strlcpy(buf, "notty", sizeof buf);
1996: return buf;
1997: }
1998:
1999: void
2000: session_proctitle(Session *s)
2001: {
2002: if (s->pw == NULL)
2003: error("no user for session %d", s->self);
2004: else
2005: setproctitle("%s@%s", s->pw->pw_name, session_tty_list());
1.81 markus 2006: }
2007:
2008: int
2009: session_setup_x11fwd(Session *s)
2010: {
2011: struct stat st;
1.109 stevesk 2012: char display[512], auth_display[512];
2013: char hostname[MAXHOSTNAMELEN];
1.184 djm 2014: u_int i;
1.81 markus 2015:
2016: if (no_x11_forwarding_flag) {
2017: packet_send_debug("X11 forwarding disabled in user configuration file.");
2018: return 0;
2019: }
2020: if (!options.x11_forwarding) {
2021: debug("X11 forwarding disabled in server configuration file.");
2022: return 0;
2023: }
2024: if (!options.xauth_location ||
2025: (stat(options.xauth_location, &st) == -1)) {
2026: packet_send_debug("No xauth program; cannot forward with spoofing.");
1.91 markus 2027: return 0;
2028: }
2029: if (options.use_login) {
2030: packet_send_debug("X11 forwarding disabled; "
2031: "not compatible with UseLogin=yes.");
1.81 markus 2032: return 0;
2033: }
1.87 markus 2034: if (s->display != NULL) {
1.81 markus 2035: debug("X11 display already set.");
2036: return 0;
2037: }
1.140 deraadt 2038: if (x11_create_display_inet(options.x11_display_offset,
2039: options.x11_use_localhost, s->single_connection,
1.184 djm 2040: &s->display_number, &s->x11_chanids) == -1) {
1.87 markus 2041: debug("x11_create_display_inet failed.");
1.81 markus 2042: return 0;
1.184 djm 2043: }
2044: for (i = 0; s->x11_chanids[i] != -1; i++) {
2045: channel_register_cleanup(s->x11_chanids[i],
1.187 djm 2046: session_close_single_x11, 0);
1.81 markus 2047: }
1.109 stevesk 2048:
2049: /* Set up a suitable value for the DISPLAY variable. */
2050: if (gethostname(hostname, sizeof(hostname)) < 0)
2051: fatal("gethostname: %.100s", strerror(errno));
2052: /*
2053: * auth_display must be used as the displayname when the
2054: * authorization entry is added with xauth(1). This will be
2055: * different than the DISPLAY string for localhost displays.
2056: */
1.119 stevesk 2057: if (options.x11_use_localhost) {
1.140 deraadt 2058: snprintf(display, sizeof display, "localhost:%u.%u",
1.109 stevesk 2059: s->display_number, s->screen);
1.140 deraadt 2060: snprintf(auth_display, sizeof auth_display, "unix:%u.%u",
1.118 stevesk 2061: s->display_number, s->screen);
1.109 stevesk 2062: s->display = xstrdup(display);
1.118 stevesk 2063: s->auth_display = xstrdup(auth_display);
1.109 stevesk 2064: } else {
1.140 deraadt 2065: snprintf(display, sizeof display, "%.400s:%u.%u", hostname,
1.109 stevesk 2066: s->display_number, s->screen);
2067: s->display = xstrdup(display);
1.118 stevesk 2068: s->auth_display = xstrdup(display);
1.109 stevesk 2069: }
2070:
1.81 markus 2071: return 1;
1.2 markus 2072: }
2073:
1.94 itojun 2074: static void
1.49 markus 2075: do_authenticated2(Authctxt *authctxt)
1.2 markus 2076: {
1.97 markus 2077: server_loop2(authctxt);
1.165 markus 2078: }
2079:
2080: void
2081: do_cleanup(Authctxt *authctxt)
2082: {
2083: static int called = 0;
2084:
2085: debug("do_cleanup");
2086:
2087: /* no cleanup if we're in the child for login shell */
2088: if (is_child)
2089: return;
2090:
2091: /* avoid double cleanup */
2092: if (called)
2093: return;
2094: called = 1;
2095:
1.218 markus 2096: if (authctxt == NULL || !authctxt->authenticated)
1.165 markus 2097: return;
2098: #ifdef KRB5
2099: if (options.kerberos_ticket_cleanup &&
2100: authctxt->krb5_ctx)
2101: krb5_cleanup_proc(authctxt);
1.161 markus 2102: #endif
1.165 markus 2103:
2104: #ifdef GSSAPI
2105: if (compat20 && options.gss_cleanup_creds)
2106: ssh_gssapi_cleanup_creds();
2107: #endif
2108:
2109: /* remove agent socket */
2110: auth_sock_cleanup_proc(authctxt->pw);
2111:
2112: /*
2113: * Cleanup ptys/utmp only if privsep is disabled,
2114: * or if running in monitor.
2115: */
2116: if (!use_privsep || mm_is_monitor())
2117: session_destroy_all(session_pty_cleanup2);
1.1 markus 2118: }
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