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1 | /* $OpenBSD: session.c,v 1.230 2008/02/22 05:58:56 djm Exp $ */ | |
2 | /* | |
3 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland | |
4 | * All rights reserved | |
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 | * | |
12 | * SSH2 support by Markus Friedl. | |
13 | * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved. | |
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. | |
34 | */ | |
35 | ||
36 | #include "includes.h" | |
37 | ||
38 | #include <sys/types.h> | |
39 | #include <sys/param.h> | |
40 | #ifdef HAVE_SYS_STAT_H | |
41 | # include <sys/stat.h> | |
42 | #endif | |
43 | #include <sys/socket.h> | |
44 | #include <sys/un.h> | |
45 | #include <sys/wait.h> | |
46 | ||
47 | #include <arpa/inet.h> | |
48 | ||
49 | #include <errno.h> | |
50 | #include <grp.h> | |
51 | #ifdef HAVE_PATHS_H | |
52 | #include <paths.h> | |
53 | #endif | |
54 | #include <pwd.h> | |
55 | #include <signal.h> | |
56 | #include <stdarg.h> | |
57 | #include <stdio.h> | |
58 | #include <stdlib.h> | |
59 | #include <string.h> | |
60 | #include <unistd.h> | |
61 | ||
62 | #include "xmalloc.h" | |
63 | #include "ssh.h" | |
64 | #include "ssh1.h" | |
65 | #include "ssh2.h" | |
66 | #include "sshpty.h" | |
67 | #include "packet.h" | |
68 | #include "buffer.h" | |
69 | #include "match.h" | |
70 | #include "uidswap.h" | |
71 | #include "compat.h" | |
72 | #include "channels.h" | |
73 | #include "key.h" | |
74 | #include "cipher.h" | |
75 | #ifdef GSSAPI | |
76 | #include "ssh-gss.h" | |
77 | #endif | |
78 | #include "hostfile.h" | |
79 | #include "auth.h" | |
80 | #include "auth-options.h" | |
81 | #include "pathnames.h" | |
82 | #include "log.h" | |
83 | #include "servconf.h" | |
84 | #include "sshlogin.h" | |
85 | #include "serverloop.h" | |
86 | #include "canohost.h" | |
87 | #include "misc.h" | |
88 | #include "session.h" | |
89 | #include "kex.h" | |
90 | #include "monitor_wrap.h" | |
91 | #include "sftp.h" | |
92 | ||
93 | #if defined(KRB5) && defined(USE_AFS) | |
94 | #include <kafs.h> | |
95 | #endif | |
96 | ||
97 | /* func */ | |
98 | ||
99 | Session *session_new(void); | |
100 | void session_set_fds(Session *, int, int, int); | |
101 | void session_pty_cleanup(Session *); | |
102 | void session_proctitle(Session *); | |
103 | int session_setup_x11fwd(Session *); | |
104 | void do_exec_pty(Session *, const char *); | |
105 | void do_exec_no_pty(Session *, const char *); | |
106 | void do_exec(Session *, const char *); | |
107 | void do_login(Session *, const char *); | |
108 | #ifdef LOGIN_NEEDS_UTMPX | |
109 | static void do_pre_login(Session *s); | |
110 | #endif | |
111 | void do_child(Session *, const char *); | |
112 | void do_motd(void); | |
113 | int check_quietlogin(Session *, const char *); | |
114 | ||
115 | static void do_authenticated1(Authctxt *); | |
116 | static void do_authenticated2(Authctxt *); | |
117 | ||
118 | static int session_pty_req(Session *); | |
119 | ||
120 | /* import */ | |
121 | extern ServerOptions options; | |
122 | extern char *__progname; | |
123 | extern int log_stderr; | |
124 | extern int debug_flag; | |
125 | extern u_int utmp_len; | |
126 | extern int startup_pipe; | |
127 | extern void destroy_sensitive_data(void); | |
128 | extern Buffer loginmsg; | |
129 | ||
130 | /* original command from peer. */ | |
131 | const char *original_command = NULL; | |
132 | ||
133 | /* data */ | |
134 | #define MAX_SESSIONS 20 | |
135 | Session sessions[MAX_SESSIONS]; | |
136 | ||
137 | #define SUBSYSTEM_NONE 0 | |
138 | #define SUBSYSTEM_EXT 1 | |
139 | #define SUBSYSTEM_INT_SFTP 2 | |
140 | ||
141 | #ifdef HAVE_LOGIN_CAP | |
142 | login_cap_t *lc; | |
143 | #endif | |
144 | ||
145 | static int is_child = 0; | |
146 | ||
147 | /* Name and directory of socket for authentication agent forwarding. */ | |
148 | static char *auth_sock_name = NULL; | |
149 | static char *auth_sock_dir = NULL; | |
150 | ||
151 | /* removes the agent forwarding socket */ | |
152 | ||
153 | static void | |
154 | auth_sock_cleanup_proc(struct passwd *pw) | |
155 | { | |
156 | if (auth_sock_name != NULL) { | |
157 | temporarily_use_uid(pw); | |
158 | unlink(auth_sock_name); | |
159 | rmdir(auth_sock_dir); | |
160 | auth_sock_name = NULL; | |
161 | restore_uid(); | |
162 | } | |
163 | } | |
164 | ||
165 | static int | |
166 | auth_input_request_forwarding(struct passwd * pw) | |
167 | { | |
168 | Channel *nc; | |
169 | int sock; | |
170 | struct sockaddr_un sunaddr; | |
171 | ||
172 | if (auth_sock_name != NULL) { | |
173 | error("authentication forwarding requested twice."); | |
174 | return 0; | |
175 | } | |
176 | ||
177 | /* Temporarily drop privileged uid for mkdir/bind. */ | |
178 | temporarily_use_uid(pw); | |
179 | ||
180 | /* Allocate a buffer for the socket name, and format the name. */ | |
181 | auth_sock_name = xmalloc(MAXPATHLEN); | |
182 | auth_sock_dir = xmalloc(MAXPATHLEN); | |
183 | strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN); | |
184 | ||
185 | /* Create private directory for socket */ | |
186 | if (mkdtemp(auth_sock_dir) == NULL) { | |
187 | packet_send_debug("Agent forwarding disabled: " | |
188 | "mkdtemp() failed: %.100s", strerror(errno)); | |
189 | restore_uid(); | |
190 | xfree(auth_sock_name); | |
191 | xfree(auth_sock_dir); | |
192 | auth_sock_name = NULL; | |
193 | auth_sock_dir = NULL; | |
194 | return 0; | |
195 | } | |
196 | snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%ld", | |
197 | auth_sock_dir, (long) getpid()); | |
198 | ||
199 | /* Create the socket. */ | |
200 | sock = socket(AF_UNIX, SOCK_STREAM, 0); | |
201 | if (sock < 0) | |
202 | packet_disconnect("socket: %.100s", strerror(errno)); | |
203 | ||
204 | /* Bind it to the name. */ | |
205 | memset(&sunaddr, 0, sizeof(sunaddr)); | |
206 | sunaddr.sun_family = AF_UNIX; | |
207 | strlcpy(sunaddr.sun_path, auth_sock_name, sizeof(sunaddr.sun_path)); | |
208 | ||
209 | if (bind(sock, (struct sockaddr *)&sunaddr, sizeof(sunaddr)) < 0) | |
210 | packet_disconnect("bind: %.100s", strerror(errno)); | |
211 | ||
212 | /* Restore the privileged uid. */ | |
213 | restore_uid(); | |
214 | ||
215 | /* Start listening on the socket. */ | |
216 | if (listen(sock, SSH_LISTEN_BACKLOG) < 0) | |
217 | packet_disconnect("listen: %.100s", strerror(errno)); | |
218 | ||
219 | /* Allocate a channel for the authentication agent socket. */ | |
220 | nc = channel_new("auth socket", | |
221 | SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1, | |
222 | CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, | |
223 | 0, "auth socket", 1); | |
224 | strlcpy(nc->path, auth_sock_name, sizeof(nc->path)); | |
225 | return 1; | |
226 | } | |
227 | ||
228 | static void | |
229 | display_loginmsg(void) | |
230 | { | |
231 | if (buffer_len(&loginmsg) > 0) { | |
232 | buffer_append(&loginmsg, "\0", 1); | |
233 | printf("%s", (char *)buffer_ptr(&loginmsg)); | |
234 | buffer_clear(&loginmsg); | |
235 | } | |
236 | } | |
237 | ||
238 | void | |
239 | do_authenticated(Authctxt *authctxt) | |
240 | { | |
241 | setproctitle("%s", authctxt->pw->pw_name); | |
242 | ||
243 | /* setup the channel layer */ | |
244 | if (!no_port_forwarding_flag && options.allow_tcp_forwarding) | |
245 | channel_permit_all_opens(); | |
246 | ||
247 | if (compat20) | |
248 | do_authenticated2(authctxt); | |
249 | else | |
250 | do_authenticated1(authctxt); | |
251 | ||
252 | do_cleanup(authctxt); | |
253 | } | |
254 | ||
255 | /* | |
256 | * Prepares for an interactive session. This is called after the user has | |
257 | * been successfully authenticated. During this message exchange, pseudo | |
258 | * terminals are allocated, X11, TCP/IP, and authentication agent forwardings | |
259 | * are requested, etc. | |
260 | */ | |
261 | static void | |
262 | do_authenticated1(Authctxt *authctxt) | |
263 | { | |
264 | Session *s; | |
265 | char *command; | |
266 | int success, type, screen_flag; | |
267 | int enable_compression_after_reply = 0; | |
268 | u_int proto_len, data_len, dlen, compression_level = 0; | |
269 | ||
270 | s = session_new(); | |
271 | if (s == NULL) { | |
272 | error("no more sessions"); | |
273 | return; | |
274 | } | |
275 | s->authctxt = authctxt; | |
276 | s->pw = authctxt->pw; | |
277 | ||
278 | /* | |
279 | * We stay in this loop until the client requests to execute a shell | |
280 | * or a command. | |
281 | */ | |
282 | for (;;) { | |
283 | success = 0; | |
284 | ||
285 | /* Get a packet from the client. */ | |
286 | type = packet_read(); | |
287 | ||
288 | /* Process the packet. */ | |
289 | switch (type) { | |
290 | case SSH_CMSG_REQUEST_COMPRESSION: | |
291 | compression_level = packet_get_int(); | |
292 | packet_check_eom(); | |
293 | if (compression_level < 1 || compression_level > 9) { | |
294 | packet_send_debug("Received invalid compression level %d.", | |
295 | compression_level); | |
296 | break; | |
297 | } | |
298 | if (options.compression == COMP_NONE) { | |
299 | debug2("compression disabled"); | |
300 | break; | |
301 | } | |
302 | /* Enable compression after we have responded with SUCCESS. */ | |
303 | enable_compression_after_reply = 1; | |
304 | success = 1; | |
305 | break; | |
306 | ||
307 | case SSH_CMSG_REQUEST_PTY: | |
308 | success = session_pty_req(s); | |
309 | break; | |
310 | ||
311 | case SSH_CMSG_X11_REQUEST_FORWARDING: | |
312 | s->auth_proto = packet_get_string(&proto_len); | |
313 | s->auth_data = packet_get_string(&data_len); | |
314 | ||
315 | screen_flag = packet_get_protocol_flags() & | |
316 | SSH_PROTOFLAG_SCREEN_NUMBER; | |
317 | debug2("SSH_PROTOFLAG_SCREEN_NUMBER: %d", screen_flag); | |
318 | ||
319 | if (packet_remaining() == 4) { | |
320 | if (!screen_flag) | |
321 | debug2("Buggy client: " | |
322 | "X11 screen flag missing"); | |
323 | s->screen = packet_get_int(); | |
324 | } else { | |
325 | s->screen = 0; | |
326 | } | |
327 | packet_check_eom(); | |
328 | success = session_setup_x11fwd(s); | |
329 | if (!success) { | |
330 | xfree(s->auth_proto); | |
331 | xfree(s->auth_data); | |
332 | s->auth_proto = NULL; | |
333 | s->auth_data = NULL; | |
334 | } | |
335 | break; | |
336 | ||
337 | case SSH_CMSG_AGENT_REQUEST_FORWARDING: | |
338 | if (no_agent_forwarding_flag || compat13) { | |
339 | debug("Authentication agent forwarding not permitted for this authentication."); | |
340 | break; | |
341 | } | |
342 | debug("Received authentication agent forwarding request."); | |
343 | success = auth_input_request_forwarding(s->pw); | |
344 | break; | |
345 | ||
346 | case SSH_CMSG_PORT_FORWARD_REQUEST: | |
347 | if (no_port_forwarding_flag) { | |
348 | debug("Port forwarding not permitted for this authentication."); | |
349 | break; | |
350 | } | |
351 | if (!options.allow_tcp_forwarding) { | |
352 | debug("Port forwarding not permitted."); | |
353 | break; | |
354 | } | |
355 | debug("Received TCP/IP port forwarding request."); | |
356 | if (channel_input_port_forward_request(s->pw->pw_uid == 0, | |
357 | options.gateway_ports) < 0) { | |
358 | debug("Port forwarding failed."); | |
359 | break; | |
360 | } | |
361 | success = 1; | |
362 | break; | |
363 | ||
364 | case SSH_CMSG_MAX_PACKET_SIZE: | |
365 | if (packet_set_maxsize(packet_get_int()) > 0) | |
366 | success = 1; | |
367 | break; | |
368 | ||
369 | case SSH_CMSG_EXEC_SHELL: | |
370 | case SSH_CMSG_EXEC_CMD: | |
371 | if (type == SSH_CMSG_EXEC_CMD) { | |
372 | command = packet_get_string(&dlen); | |
373 | debug("Exec command '%.500s'", command); | |
374 | do_exec(s, command); | |
375 | xfree(command); | |
376 | } else { | |
377 | do_exec(s, NULL); | |
378 | } | |
379 | packet_check_eom(); | |
380 | session_close(s); | |
381 | return; | |
382 | ||
383 | default: | |
384 | /* | |
385 | * Any unknown messages in this phase are ignored, | |
386 | * and a failure message is returned. | |
387 | */ | |
388 | logit("Unknown packet type received after authentication: %d", type); | |
389 | } | |
390 | packet_start(success ? SSH_SMSG_SUCCESS : SSH_SMSG_FAILURE); | |
391 | packet_send(); | |
392 | packet_write_wait(); | |
393 | ||
394 | /* Enable compression now that we have replied if appropriate. */ | |
395 | if (enable_compression_after_reply) { | |
396 | enable_compression_after_reply = 0; | |
397 | packet_start_compression(compression_level); | |
398 | } | |
399 | } | |
400 | } | |
401 | ||
402 | /* | |
403 | * This is called to fork and execute a command when we have no tty. This | |
404 | * will call do_child from the child, and server_loop from the parent after | |
405 | * setting up file descriptors and such. | |
406 | */ | |
407 | void | |
408 | do_exec_no_pty(Session *s, const char *command) | |
409 | { | |
410 | pid_t pid; | |
411 | ||
412 | #ifdef USE_PIPES | |
413 | int pin[2], pout[2], perr[2]; | |
414 | /* Allocate pipes for communicating with the program. */ | |
415 | if (pipe(pin) < 0 || pipe(pout) < 0 || pipe(perr) < 0) | |
416 | packet_disconnect("Could not create pipes: %.100s", | |
417 | strerror(errno)); | |
418 | #else /* USE_PIPES */ | |
419 | int inout[2], err[2]; | |
420 | /* Uses socket pairs to communicate with the program. */ | |
421 | if (socketpair(AF_UNIX, SOCK_STREAM, 0, inout) < 0 || | |
422 | socketpair(AF_UNIX, SOCK_STREAM, 0, err) < 0) | |
423 | packet_disconnect("Could not create socket pairs: %.100s", | |
424 | strerror(errno)); | |
425 | #endif /* USE_PIPES */ | |
426 | if (s == NULL) | |
427 | fatal("do_exec_no_pty: no session"); | |
428 | ||
429 | session_proctitle(s); | |
430 | ||
431 | /* Fork the child. */ | |
432 | if ((pid = fork()) == 0) { | |
433 | is_child = 1; | |
434 | ||
435 | /* Child. Reinitialize the log since the pid has changed. */ | |
436 | log_init(__progname, options.log_level, options.log_facility, log_stderr); | |
437 | ||
438 | /* | |
439 | * Create a new session and process group since the 4.4BSD | |
440 | * setlogin() affects the entire process group. | |
441 | */ | |
442 | if (setsid() < 0) | |
443 | error("setsid failed: %.100s", strerror(errno)); | |
444 | ||
445 | #ifdef USE_PIPES | |
446 | /* | |
447 | * Redirect stdin. We close the parent side of the socket | |
448 | * pair, and make the child side the standard input. | |
449 | */ | |
450 | close(pin[1]); | |
451 | if (dup2(pin[0], 0) < 0) | |
452 | perror("dup2 stdin"); | |
453 | close(pin[0]); | |
454 | ||
455 | /* Redirect stdout. */ | |
456 | close(pout[0]); | |
457 | if (dup2(pout[1], 1) < 0) | |
458 | perror("dup2 stdout"); | |
459 | close(pout[1]); | |
460 | ||
461 | /* Redirect stderr. */ | |
462 | close(perr[0]); | |
463 | if (dup2(perr[1], 2) < 0) | |
464 | perror("dup2 stderr"); | |
465 | close(perr[1]); | |
466 | #else /* USE_PIPES */ | |
467 | /* | |
468 | * Redirect stdin, stdout, and stderr. Stdin and stdout will | |
469 | * use the same socket, as some programs (particularly rdist) | |
470 | * seem to depend on it. | |
471 | */ | |
472 | close(inout[1]); | |
473 | close(err[1]); | |
474 | if (dup2(inout[0], 0) < 0) /* stdin */ | |
475 | perror("dup2 stdin"); | |
476 | if (dup2(inout[0], 1) < 0) /* stdout. Note: same socket as stdin. */ | |
477 | perror("dup2 stdout"); | |
478 | if (dup2(err[0], 2) < 0) /* stderr */ | |
479 | perror("dup2 stderr"); | |
480 | #endif /* USE_PIPES */ | |
481 | ||
482 | #ifdef _UNICOS | |
483 | cray_init_job(s->pw); /* set up cray jid and tmpdir */ | |
484 | #endif | |
485 | ||
486 | /* Do processing for the child (exec command etc). */ | |
487 | do_child(s, command); | |
488 | /* NOTREACHED */ | |
489 | } | |
490 | #ifdef _UNICOS | |
491 | signal(WJSIGNAL, cray_job_termination_handler); | |
492 | #endif /* _UNICOS */ | |
493 | #ifdef HAVE_CYGWIN | |
494 | if (is_winnt) | |
495 | cygwin_set_impersonation_token(INVALID_HANDLE_VALUE); | |
496 | #endif | |
497 | if (pid < 0) | |
498 | packet_disconnect("fork failed: %.100s", strerror(errno)); | |
499 | s->pid = pid; | |
500 | /* Set interactive/non-interactive mode. */ | |
501 | packet_set_interactive(s->display != NULL); | |
502 | #ifdef USE_PIPES | |
503 | /* We are the parent. Close the child sides of the pipes. */ | |
504 | close(pin[0]); | |
505 | close(pout[1]); | |
506 | close(perr[1]); | |
507 | ||
508 | if (compat20) { | |
509 | if (s->is_subsystem) { | |
510 | close(perr[0]); | |
511 | perr[0] = -1; | |
512 | } | |
513 | session_set_fds(s, pin[1], pout[0], perr[0]); | |
514 | } else { | |
515 | /* Enter the interactive session. */ | |
516 | server_loop(pid, pin[1], pout[0], perr[0]); | |
517 | /* server_loop has closed pin[1], pout[0], and perr[0]. */ | |
518 | } | |
519 | #else /* USE_PIPES */ | |
520 | /* We are the parent. Close the child sides of the socket pairs. */ | |
521 | close(inout[0]); | |
522 | close(err[0]); | |
523 | ||
524 | /* | |
525 | * Clear loginmsg, since it's the child's responsibility to display | |
526 | * it to the user, otherwise multiple sessions may accumulate | |
527 | * multiple copies of the login messages. | |
528 | */ | |
529 | buffer_clear(&loginmsg); | |
530 | ||
531 | /* | |
532 | * Enter the interactive session. Note: server_loop must be able to | |
533 | * handle the case that fdin and fdout are the same. | |
534 | */ | |
535 | if (compat20) { | |
536 | session_set_fds(s, inout[1], inout[1], s->is_subsystem ? -1 : err[1]); | |
537 | } else { | |
538 | server_loop(pid, inout[1], inout[1], err[1]); | |
539 | /* server_loop has closed inout[1] and err[1]. */ | |
540 | } | |
541 | #endif /* USE_PIPES */ | |
542 | } | |
543 | ||
544 | /* | |
545 | * This is called to fork and execute a command when we have a tty. This | |
546 | * will call do_child from the child, and server_loop from the parent after | |
547 | * setting up file descriptors, controlling tty, updating wtmp, utmp, | |
548 | * lastlog, and other such operations. | |
549 | */ | |
550 | void | |
551 | do_exec_pty(Session *s, const char *command) | |
552 | { | |
553 | int fdout, ptyfd, ttyfd, ptymaster; | |
554 | pid_t pid; | |
555 | ||
556 | if (s == NULL) | |
557 | fatal("do_exec_pty: no session"); | |
558 | ptyfd = s->ptyfd; | |
559 | ttyfd = s->ttyfd; | |
560 | ||
561 | /* Fork the child. */ | |
562 | if ((pid = fork()) == 0) { | |
563 | is_child = 1; | |
564 | ||
565 | /* Child. Reinitialize the log because the pid has changed. */ | |
566 | log_init(__progname, options.log_level, options.log_facility, log_stderr); | |
567 | /* Close the master side of the pseudo tty. */ | |
568 | close(ptyfd); | |
569 | ||
570 | /* Make the pseudo tty our controlling tty. */ | |
571 | pty_make_controlling_tty(&ttyfd, s->tty); | |
572 | ||
573 | /* Redirect stdin/stdout/stderr from the pseudo tty. */ | |
574 | if (dup2(ttyfd, 0) < 0) | |
575 | error("dup2 stdin: %s", strerror(errno)); | |
576 | if (dup2(ttyfd, 1) < 0) | |
577 | error("dup2 stdout: %s", strerror(errno)); | |
578 | if (dup2(ttyfd, 2) < 0) | |
579 | error("dup2 stderr: %s", strerror(errno)); | |
580 | ||
581 | /* Close the extra descriptor for the pseudo tty. */ | |
582 | close(ttyfd); | |
583 | ||
584 | /* record login, etc. similar to login(1) */ | |
585 | #ifndef HAVE_OSF_SIA | |
586 | if (!(options.use_login && command == NULL)) { | |
587 | #ifdef _UNICOS | |
588 | cray_init_job(s->pw); /* set up cray jid and tmpdir */ | |
589 | #endif /* _UNICOS */ | |
590 | do_login(s, command); | |
591 | } | |
592 | # ifdef LOGIN_NEEDS_UTMPX | |
593 | else | |
594 | do_pre_login(s); | |
595 | # endif | |
596 | #endif | |
597 | ||
598 | /* Do common processing for the child, such as execing the command. */ | |
599 | do_child(s, command); | |
600 | /* NOTREACHED */ | |
601 | } | |
602 | #ifdef _UNICOS | |
603 | signal(WJSIGNAL, cray_job_termination_handler); | |
604 | #endif /* _UNICOS */ | |
605 | #ifdef HAVE_CYGWIN | |
606 | if (is_winnt) | |
607 | cygwin_set_impersonation_token(INVALID_HANDLE_VALUE); | |
608 | #endif | |
609 | if (pid < 0) | |
610 | packet_disconnect("fork failed: %.100s", strerror(errno)); | |
611 | s->pid = pid; | |
612 | ||
613 | /* Parent. Close the slave side of the pseudo tty. */ | |
614 | close(ttyfd); | |
615 | ||
616 | /* | |
617 | * Create another descriptor of the pty master side for use as the | |
618 | * standard input. We could use the original descriptor, but this | |
619 | * simplifies code in server_loop. The descriptor is bidirectional. | |
620 | */ | |
621 | fdout = dup(ptyfd); | |
622 | if (fdout < 0) | |
623 | packet_disconnect("dup #1 failed: %.100s", strerror(errno)); | |
624 | ||
625 | /* we keep a reference to the pty master */ | |
626 | ptymaster = dup(ptyfd); | |
627 | if (ptymaster < 0) | |
628 | packet_disconnect("dup #2 failed: %.100s", strerror(errno)); | |
629 | s->ptymaster = ptymaster; | |
630 | ||
631 | /* Enter interactive session. */ | |
632 | packet_set_interactive(1); | |
633 | if (compat20) { | |
634 | session_set_fds(s, ptyfd, fdout, -1); | |
635 | } else { | |
636 | server_loop(pid, ptyfd, fdout, -1); | |
637 | /* server_loop _has_ closed ptyfd and fdout. */ | |
638 | } | |
639 | } | |
640 | ||
641 | #ifdef LOGIN_NEEDS_UTMPX | |
642 | static void | |
643 | do_pre_login(Session *s) | |
644 | { | |
645 | socklen_t fromlen; | |
646 | struct sockaddr_storage from; | |
647 | pid_t pid = getpid(); | |
648 | ||
649 | /* | |
650 | * Get IP address of client. If the connection is not a socket, let | |
651 | * the address be 0.0.0.0. | |
652 | */ | |
653 | memset(&from, 0, sizeof(from)); | |
654 | fromlen = sizeof(from); | |
655 | if (packet_connection_is_on_socket()) { | |
656 | if (getpeername(packet_get_connection_in(), | |
657 | (struct sockaddr *)&from, &fromlen) < 0) { | |
658 | debug("getpeername: %.100s", strerror(errno)); | |
659 | cleanup_exit(255); | |
660 | } | |
661 | } | |
662 | ||
663 | record_utmp_only(pid, s->tty, s->pw->pw_name, | |
664 | get_remote_name_or_ip(utmp_len, options.use_dns), | |
665 | (struct sockaddr *)&from, fromlen); | |
666 | } | |
667 | #endif | |
668 | ||
669 | /* | |
670 | * This is called to fork and execute a command. If another command is | |
671 | * to be forced, execute that instead. | |
672 | */ | |
673 | void | |
674 | do_exec(Session *s, const char *command) | |
675 | { | |
676 | if (options.adm_forced_command) { | |
677 | original_command = command; | |
678 | command = options.adm_forced_command; | |
679 | if (strcmp(INTERNAL_SFTP_NAME, command) == 0) | |
680 | s->is_subsystem = SUBSYSTEM_INT_SFTP; | |
681 | else if (s->is_subsystem) | |
682 | s->is_subsystem = SUBSYSTEM_EXT; | |
683 | debug("Forced command (config) '%.900s'", command); | |
684 | } else if (forced_command) { | |
685 | original_command = command; | |
686 | command = forced_command; | |
687 | if (strcmp(INTERNAL_SFTP_NAME, command) == 0) | |
688 | s->is_subsystem = SUBSYSTEM_INT_SFTP; | |
689 | else if (s->is_subsystem) | |
690 | s->is_subsystem = SUBSYSTEM_EXT; | |
691 | debug("Forced command (key option) '%.900s'", command); | |
692 | } | |
693 | ||
694 | #ifdef SSH_AUDIT_EVENTS | |
695 | if (command != NULL) | |
696 | PRIVSEP(audit_run_command(command)); | |
697 | else if (s->ttyfd == -1) { | |
698 | char *shell = s->pw->pw_shell; | |
699 | ||
700 | if (shell[0] == '\0') /* empty shell means /bin/sh */ | |
701 | shell =_PATH_BSHELL; | |
702 | PRIVSEP(audit_run_command(shell)); | |
703 | } | |
704 | #endif | |
705 | if (s->ttyfd != -1) | |
706 | do_exec_pty(s, command); | |
707 | else | |
708 | do_exec_no_pty(s, command); | |
709 | ||
710 | original_command = NULL; | |
711 | ||
712 | /* | |
713 | * Clear loginmsg: it's the child's responsibility to display | |
714 | * it to the user, otherwise multiple sessions may accumulate | |
715 | * multiple copies of the login messages. | |
716 | */ | |
717 | buffer_clear(&loginmsg); | |
718 | } | |
719 | ||
720 | /* administrative, login(1)-like work */ | |
721 | void | |
722 | do_login(Session *s, const char *command) | |
723 | { | |
724 | socklen_t fromlen; | |
725 | struct sockaddr_storage from; | |
726 | struct passwd * pw = s->pw; | |
727 | pid_t pid = getpid(); | |
728 | ||
729 | /* | |
730 | * Get IP address of client. If the connection is not a socket, let | |
731 | * the address be 0.0.0.0. | |
732 | */ | |
733 | memset(&from, 0, sizeof(from)); | |
734 | fromlen = sizeof(from); | |
735 | if (packet_connection_is_on_socket()) { | |
736 | if (getpeername(packet_get_connection_in(), | |
737 | (struct sockaddr *) & from, &fromlen) < 0) { | |
738 | debug("getpeername: %.100s", strerror(errno)); | |
739 | cleanup_exit(255); | |
740 | } | |
741 | } | |
742 | ||
743 | /* Record that there was a login on that tty from the remote host. */ | |
744 | if (!use_privsep) | |
745 | record_login(pid, s->tty, pw->pw_name, pw->pw_uid, | |
746 | get_remote_name_or_ip(utmp_len, | |
747 | options.use_dns), | |
748 | (struct sockaddr *)&from, fromlen); | |
749 | ||
750 | #ifdef USE_PAM | |
751 | /* | |
752 | * If password change is needed, do it now. | |
753 | * This needs to occur before the ~/.hushlogin check. | |
754 | */ | |
755 | if (options.use_pam && !use_privsep && s->authctxt->force_pwchange) { | |
756 | display_loginmsg(); | |
757 | do_pam_chauthtok(); | |
758 | s->authctxt->force_pwchange = 0; | |
759 | /* XXX - signal [net] parent to enable forwardings */ | |
760 | } | |
761 | #endif | |
762 | ||
763 | if (check_quietlogin(s, command)) | |
764 | return; | |
765 | ||
766 | display_loginmsg(); | |
767 | ||
768 | do_motd(); | |
769 | } | |
770 | ||
771 | /* | |
772 | * Display the message of the day. | |
773 | */ | |
774 | void | |
775 | do_motd(void) | |
776 | { | |
777 | FILE *f; | |
778 | char buf[256]; | |
779 | ||
780 | if (options.print_motd) { | |
781 | #ifdef HAVE_LOGIN_CAP | |
782 | f = fopen(login_getcapstr(lc, "welcome", "/etc/motd", | |
783 | "/etc/motd"), "r"); | |
784 | #else | |
785 | f = fopen("/etc/motd", "r"); | |
786 | #endif | |
787 | if (f) { | |
788 | while (fgets(buf, sizeof(buf), f)) | |
789 | fputs(buf, stdout); | |
790 | fclose(f); | |
791 | } | |
792 | } | |
793 | } | |
794 | ||
795 | ||
796 | /* | |
797 | * Check for quiet login, either .hushlogin or command given. | |
798 | */ | |
799 | int | |
800 | check_quietlogin(Session *s, const char *command) | |
801 | { | |
802 | char buf[256]; | |
803 | struct passwd *pw = s->pw; | |
804 | struct stat st; | |
805 | ||
806 | /* Return 1 if .hushlogin exists or a command given. */ | |
807 | if (command != NULL) | |
808 | return 1; | |
809 | snprintf(buf, sizeof(buf), "%.200s/.hushlogin", pw->pw_dir); | |
810 | #ifdef HAVE_LOGIN_CAP | |
811 | if (login_getcapbool(lc, "hushlogin", 0) || stat(buf, &st) >= 0) | |
812 | return 1; | |
813 | #else | |
814 | if (stat(buf, &st) >= 0) | |
815 | return 1; | |
816 | #endif | |
817 | return 0; | |
818 | } | |
819 | ||
820 | /* | |
821 | * Sets the value of the given variable in the environment. If the variable | |
822 | * already exists, its value is overriden. | |
823 | */ | |
824 | void | |
825 | child_set_env(char ***envp, u_int *envsizep, const char *name, | |
826 | const char *value) | |
827 | { | |
828 | char **env; | |
829 | u_int envsize; | |
830 | u_int i, namelen; | |
831 | ||
832 | /* | |
833 | * If we're passed an uninitialized list, allocate a single null | |
834 | * entry before continuing. | |
835 | */ | |
836 | if (*envp == NULL && *envsizep == 0) { | |
837 | *envp = xmalloc(sizeof(char *)); | |
838 | *envp[0] = NULL; | |
839 | *envsizep = 1; | |
840 | } | |
841 | ||
842 | /* | |
843 | * Find the slot where the value should be stored. If the variable | |
844 | * already exists, we reuse the slot; otherwise we append a new slot | |
845 | * at the end of the array, expanding if necessary. | |
846 | */ | |
847 | env = *envp; | |
848 | namelen = strlen(name); | |
849 | for (i = 0; env[i]; i++) | |
850 | if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=') | |
851 | break; | |
852 | if (env[i]) { | |
853 | /* Reuse the slot. */ | |
854 | xfree(env[i]); | |
855 | } else { | |
856 | /* New variable. Expand if necessary. */ | |
857 | envsize = *envsizep; | |
858 | if (i >= envsize - 1) { | |
859 | if (envsize >= 1000) | |
860 | fatal("child_set_env: too many env vars"); | |
861 | envsize += 50; | |
862 | env = (*envp) = xrealloc(env, envsize, sizeof(char *)); | |
863 | *envsizep = envsize; | |
864 | } | |
865 | /* Need to set the NULL pointer at end of array beyond the new slot. */ | |
866 | env[i + 1] = NULL; | |
867 | } | |
868 | ||
869 | /* Allocate space and format the variable in the appropriate slot. */ | |
870 | env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1); | |
871 | snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value); | |
872 | } | |
873 | ||
874 | /* | |
875 | * Reads environment variables from the given file and adds/overrides them | |
876 | * into the environment. If the file does not exist, this does nothing. | |
877 | * Otherwise, it must consist of empty lines, comments (line starts with '#') | |
878 | * and assignments of the form name=value. No other forms are allowed. | |
879 | */ | |
880 | static void | |
881 | read_environment_file(char ***env, u_int *envsize, | |
882 | const char *filename) | |
883 | { | |
884 | FILE *f; | |
885 | char buf[4096]; | |
886 | char *cp, *value; | |
887 | u_int lineno = 0; | |
888 | ||
889 | f = fopen(filename, "r"); | |
890 | if (!f) | |
891 | return; | |
892 | ||
893 | while (fgets(buf, sizeof(buf), f)) { | |
894 | if (++lineno > 1000) | |
895 | fatal("Too many lines in environment file %s", filename); | |
896 | for (cp = buf; *cp == ' ' || *cp == '\t'; cp++) | |
897 | ; | |
898 | if (!*cp || *cp == '#' || *cp == '\n') | |
899 | continue; | |
900 | ||
901 | cp[strcspn(cp, "\n")] = '\0'; | |
902 | ||
903 | value = strchr(cp, '='); | |
904 | if (value == NULL) { | |
905 | fprintf(stderr, "Bad line %u in %.100s\n", lineno, | |
906 | filename); | |
907 | continue; | |
908 | } | |
909 | /* | |
910 | * Replace the equals sign by nul, and advance value to | |
911 | * the value string. | |
912 | */ | |
913 | *value = '\0'; | |
914 | value++; | |
915 | child_set_env(env, envsize, cp, value); | |
916 | } | |
917 | fclose(f); | |
918 | } | |
919 | ||
920 | #ifdef HAVE_ETC_DEFAULT_LOGIN | |
921 | /* | |
922 | * Return named variable from specified environment, or NULL if not present. | |
923 | */ | |
924 | static char * | |
925 | child_get_env(char **env, const char *name) | |
926 | { | |
927 | int i; | |
928 | size_t len; | |
929 | ||
930 | len = strlen(name); | |
931 | for (i=0; env[i] != NULL; i++) | |
932 | if (strncmp(name, env[i], len) == 0 && env[i][len] == '=') | |
933 | return(env[i] + len + 1); | |
934 | return NULL; | |
935 | } | |
936 | ||
937 | /* | |
938 | * Read /etc/default/login. | |
939 | * We pick up the PATH (or SUPATH for root) and UMASK. | |
940 | */ | |
941 | static void | |
942 | read_etc_default_login(char ***env, u_int *envsize, uid_t uid) | |
943 | { | |
944 | char **tmpenv = NULL, *var; | |
945 | u_int i, tmpenvsize = 0; | |
946 | u_long mask; | |
947 | ||
948 | /* | |
949 | * We don't want to copy the whole file to the child's environment, | |
950 | * so we use a temporary environment and copy the variables we're | |
951 | * interested in. | |
952 | */ | |
953 | read_environment_file(&tmpenv, &tmpenvsize, "/etc/default/login"); | |
954 | ||
955 | if (tmpenv == NULL) | |
956 | return; | |
957 | ||
958 | if (uid == 0) | |
959 | var = child_get_env(tmpenv, "SUPATH"); | |
960 | else | |
961 | var = child_get_env(tmpenv, "PATH"); | |
962 | if (var != NULL) | |
963 | child_set_env(env, envsize, "PATH", var); | |
964 | ||
965 | if ((var = child_get_env(tmpenv, "UMASK")) != NULL) | |
966 | if (sscanf(var, "%5lo", &mask) == 1) | |
967 | umask((mode_t)mask); | |
968 | ||
969 | for (i = 0; tmpenv[i] != NULL; i++) | |
970 | xfree(tmpenv[i]); | |
971 | xfree(tmpenv); | |
972 | } | |
973 | #endif /* HAVE_ETC_DEFAULT_LOGIN */ | |
974 | ||
975 | void | |
976 | copy_environment(char **source, char ***env, u_int *envsize) | |
977 | { | |
978 | char *var_name, *var_val; | |
979 | int i; | |
980 | ||
981 | if (source == NULL) | |
982 | return; | |
983 | ||
984 | for(i = 0; source[i] != NULL; i++) { | |
985 | var_name = xstrdup(source[i]); | |
986 | if ((var_val = strstr(var_name, "=")) == NULL) { | |
987 | xfree(var_name); | |
988 | continue; | |
989 | } | |
990 | *var_val++ = '\0'; | |
991 | ||
992 | debug3("Copy environment: %s=%s", var_name, var_val); | |
993 | child_set_env(env, envsize, var_name, var_val); | |
994 | ||
995 | xfree(var_name); | |
996 | } | |
997 | } | |
998 | ||
999 | static char ** | |
1000 | do_setup_env(Session *s, const char *shell) | |
1001 | { | |
1002 | char buf[256]; | |
1003 | u_int i, envsize; | |
1004 | char **env, *laddr; | |
1005 | struct passwd *pw = s->pw; | |
1006 | #ifndef HAVE_LOGIN_CAP | |
1007 | char *path = NULL; | |
1008 | #endif | |
1009 | ||
1010 | /* Initialize the environment. */ | |
1011 | envsize = 100; | |
1012 | env = xcalloc(envsize, sizeof(char *)); | |
1013 | env[0] = NULL; | |
1014 | ||
1015 | #ifdef HAVE_CYGWIN | |
1016 | /* | |
1017 | * The Windows environment contains some setting which are | |
1018 | * important for a running system. They must not be dropped. | |
1019 | */ | |
1020 | { | |
1021 | char **p; | |
1022 | ||
1023 | p = fetch_windows_environment(); | |
1024 | copy_environment(p, &env, &envsize); | |
1025 | free_windows_environment(p); | |
1026 | } | |
1027 | #endif | |
1028 | ||
1029 | #ifdef GSSAPI | |
1030 | /* Allow any GSSAPI methods that we've used to alter | |
1031 | * the childs environment as they see fit | |
1032 | */ | |
1033 | ssh_gssapi_do_child(&env, &envsize); | |
1034 | #endif | |
1035 | ||
1036 | if (!options.use_login) { | |
1037 | /* Set basic environment. */ | |
1038 | for (i = 0; i < s->num_env; i++) | |
1039 | child_set_env(&env, &envsize, s->env[i].name, | |
1040 | s->env[i].val); | |
1041 | ||
1042 | child_set_env(&env, &envsize, "USER", pw->pw_name); | |
1043 | child_set_env(&env, &envsize, "LOGNAME", pw->pw_name); | |
1044 | #ifdef _AIX | |
1045 | child_set_env(&env, &envsize, "LOGIN", pw->pw_name); | |
1046 | #endif | |
1047 | child_set_env(&env, &envsize, "HOME", pw->pw_dir); | |
1048 | #ifdef HAVE_LOGIN_CAP | |
1049 | if (setusercontext(lc, pw, pw->pw_uid, LOGIN_SETPATH) < 0) | |
1050 | child_set_env(&env, &envsize, "PATH", _PATH_STDPATH); | |
1051 | else | |
1052 | child_set_env(&env, &envsize, "PATH", getenv("PATH")); | |
1053 | #else /* HAVE_LOGIN_CAP */ | |
1054 | # ifndef HAVE_CYGWIN | |
1055 | /* | |
1056 | * There's no standard path on Windows. The path contains | |
1057 | * important components pointing to the system directories, | |
1058 | * needed for loading shared libraries. So the path better | |
1059 | * remains intact here. | |
1060 | */ | |
1061 | # ifdef HAVE_ETC_DEFAULT_LOGIN | |
1062 | read_etc_default_login(&env, &envsize, pw->pw_uid); | |
1063 | path = child_get_env(env, "PATH"); | |
1064 | # endif /* HAVE_ETC_DEFAULT_LOGIN */ | |
1065 | if (path == NULL || *path == '\0') { | |
1066 | child_set_env(&env, &envsize, "PATH", | |
1067 | s->pw->pw_uid == 0 ? | |
1068 | SUPERUSER_PATH : _PATH_STDPATH); | |
1069 | } | |
1070 | # endif /* HAVE_CYGWIN */ | |
1071 | #endif /* HAVE_LOGIN_CAP */ | |
1072 | ||
1073 | snprintf(buf, sizeof buf, "%.200s/%.50s", | |
1074 | _PATH_MAILDIR, pw->pw_name); | |
1075 | child_set_env(&env, &envsize, "MAIL", buf); | |
1076 | ||
1077 | /* Normal systems set SHELL by default. */ | |
1078 | child_set_env(&env, &envsize, "SHELL", shell); | |
1079 | } | |
1080 | if (getenv("TZ")) | |
1081 | child_set_env(&env, &envsize, "TZ", getenv("TZ")); | |
1082 | ||
1083 | /* Set custom environment options from RSA authentication. */ | |
1084 | if (!options.use_login) { | |
1085 | while (custom_environment) { | |
1086 | struct envstring *ce = custom_environment; | |
1087 | char *str = ce->s; | |
1088 | ||
1089 | for (i = 0; str[i] != '=' && str[i]; i++) | |
1090 | ; | |
1091 | if (str[i] == '=') { | |
1092 | str[i] = 0; | |
1093 | child_set_env(&env, &envsize, str, str + i + 1); | |
1094 | } | |
1095 | custom_environment = ce->next; | |
1096 | xfree(ce->s); | |
1097 | xfree(ce); | |
1098 | } | |
1099 | } | |
1100 | ||
1101 | /* SSH_CLIENT deprecated */ | |
1102 | snprintf(buf, sizeof buf, "%.50s %d %d", | |
1103 | get_remote_ipaddr(), get_remote_port(), get_local_port()); | |
1104 | child_set_env(&env, &envsize, "SSH_CLIENT", buf); | |
1105 | ||
1106 | laddr = get_local_ipaddr(packet_get_connection_in()); | |
1107 | snprintf(buf, sizeof buf, "%.50s %d %.50s %d", | |
1108 | get_remote_ipaddr(), get_remote_port(), laddr, get_local_port()); | |
1109 | xfree(laddr); | |
1110 | child_set_env(&env, &envsize, "SSH_CONNECTION", buf); | |
1111 | ||
1112 | if (s->ttyfd != -1) | |
1113 | child_set_env(&env, &envsize, "SSH_TTY", s->tty); | |
1114 | if (s->term) | |
1115 | child_set_env(&env, &envsize, "TERM", s->term); | |
1116 | if (s->display) | |
1117 | child_set_env(&env, &envsize, "DISPLAY", s->display); | |
1118 | if (original_command) | |
1119 | child_set_env(&env, &envsize, "SSH_ORIGINAL_COMMAND", | |
1120 | original_command); | |
1121 | ||
1122 | #ifdef _UNICOS | |
1123 | if (cray_tmpdir[0] != '\0') | |
1124 | child_set_env(&env, &envsize, "TMPDIR", cray_tmpdir); | |
1125 | #endif /* _UNICOS */ | |
1126 | ||
1127 | /* | |
1128 | * Since we clear KRB5CCNAME at startup, if it's set now then it | |
1129 | * must have been set by a native authentication method (eg AIX or | |
1130 | * SIA), so copy it to the child. | |
1131 | */ | |
1132 | { | |
1133 | char *cp; | |
1134 | ||
1135 | if ((cp = getenv("KRB5CCNAME")) != NULL) | |
1136 | child_set_env(&env, &envsize, "KRB5CCNAME", cp); | |
1137 | } | |
1138 | ||
1139 | #ifdef _AIX | |
1140 | { | |
1141 | char *cp; | |
1142 | ||
1143 | if ((cp = getenv("AUTHSTATE")) != NULL) | |
1144 | child_set_env(&env, &envsize, "AUTHSTATE", cp); | |
1145 | read_environment_file(&env, &envsize, "/etc/environment"); | |
1146 | } | |
1147 | #endif | |
1148 | #ifdef KRB5 | |
1149 | if (s->authctxt->krb5_ccname) | |
1150 | child_set_env(&env, &envsize, "KRB5CCNAME", | |
1151 | s->authctxt->krb5_ccname); | |
1152 | #endif | |
1153 | #ifdef USE_PAM | |
1154 | /* | |
1155 | * Pull in any environment variables that may have | |
1156 | * been set by PAM. | |
1157 | */ | |
1158 | if (options.use_pam) { | |
1159 | char **p; | |
1160 | ||
1161 | p = fetch_pam_child_environment(); | |
1162 | copy_environment(p, &env, &envsize); | |
1163 | free_pam_environment(p); | |
1164 | ||
1165 | p = fetch_pam_environment(); | |
1166 | copy_environment(p, &env, &envsize); | |
1167 | free_pam_environment(p); | |
1168 | } | |
1169 | #endif /* USE_PAM */ | |
1170 | ||
1171 | if (auth_sock_name != NULL) | |
1172 | child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME, | |
1173 | auth_sock_name); | |
1174 | ||
1175 | /* read $HOME/.ssh/environment. */ | |
1176 | if (options.permit_user_env && !options.use_login) { | |
1177 | snprintf(buf, sizeof buf, "%.200s/.ssh/environment", | |
1178 | strcmp(pw->pw_dir, "/") ? pw->pw_dir : ""); | |
1179 | read_environment_file(&env, &envsize, buf); | |
1180 | } | |
1181 | if (debug_flag) { | |
1182 | /* dump the environment */ | |
1183 | fprintf(stderr, "Environment:\n"); | |
1184 | for (i = 0; env[i]; i++) | |
1185 | fprintf(stderr, " %.200s\n", env[i]); | |
1186 | } | |
1187 | return env; | |
1188 | } | |
1189 | ||
1190 | /* | |
1191 | * Run $HOME/.ssh/rc, /etc/ssh/sshrc, or xauth (whichever is found | |
1192 | * first in this order). | |
1193 | */ | |
1194 | static void | |
1195 | do_rc_files(Session *s, const char *shell) | |
1196 | { | |
1197 | FILE *f = NULL; | |
1198 | char cmd[1024]; | |
1199 | int do_xauth; | |
1200 | struct stat st; | |
1201 | ||
1202 | do_xauth = | |
1203 | s->display != NULL && s->auth_proto != NULL && s->auth_data != NULL; | |
1204 | ||
1205 | /* ignore _PATH_SSH_USER_RC for subsystems */ | |
1206 | if (!s->is_subsystem && (stat(_PATH_SSH_USER_RC, &st) >= 0)) { | |
1207 | snprintf(cmd, sizeof cmd, "%s -c '%s %s'", | |
1208 | shell, _PATH_BSHELL, _PATH_SSH_USER_RC); | |
1209 | if (debug_flag) | |
1210 | fprintf(stderr, "Running %s\n", cmd); | |
1211 | f = popen(cmd, "w"); | |
1212 | if (f) { | |
1213 | if (do_xauth) | |
1214 | fprintf(f, "%s %s\n", s->auth_proto, | |
1215 | s->auth_data); | |
1216 | pclose(f); | |
1217 | } else | |
1218 | fprintf(stderr, "Could not run %s\n", | |
1219 | _PATH_SSH_USER_RC); | |
1220 | } else if (stat(_PATH_SSH_SYSTEM_RC, &st) >= 0) { | |
1221 | if (debug_flag) | |
1222 | fprintf(stderr, "Running %s %s\n", _PATH_BSHELL, | |
1223 | _PATH_SSH_SYSTEM_RC); | |
1224 | f = popen(_PATH_BSHELL " " _PATH_SSH_SYSTEM_RC, "w"); | |
1225 | if (f) { | |
1226 | if (do_xauth) | |
1227 | fprintf(f, "%s %s\n", s->auth_proto, | |
1228 | s->auth_data); | |
1229 | pclose(f); | |
1230 | } else | |
1231 | fprintf(stderr, "Could not run %s\n", | |
1232 | _PATH_SSH_SYSTEM_RC); | |
1233 | } else if (do_xauth && options.xauth_location != NULL) { | |
1234 | /* Add authority data to .Xauthority if appropriate. */ | |
1235 | if (debug_flag) { | |
1236 | fprintf(stderr, | |
1237 | "Running %.500s remove %.100s\n", | |
1238 | options.xauth_location, s->auth_display); | |
1239 | fprintf(stderr, | |
1240 | "%.500s add %.100s %.100s %.100s\n", | |
1241 | options.xauth_location, s->auth_display, | |
1242 | s->auth_proto, s->auth_data); | |
1243 | } | |
1244 | snprintf(cmd, sizeof cmd, "%s -q -", | |
1245 | options.xauth_location); | |
1246 | f = popen(cmd, "w"); | |
1247 | if (f) { | |
1248 | fprintf(f, "remove %s\n", | |
1249 | s->auth_display); | |
1250 | fprintf(f, "add %s %s %s\n", | |
1251 | s->auth_display, s->auth_proto, | |
1252 | s->auth_data); | |
1253 | pclose(f); | |
1254 | } else { | |
1255 | fprintf(stderr, "Could not run %s\n", | |
1256 | cmd); | |
1257 | } | |
1258 | } | |
1259 | } | |
1260 | ||
1261 | static void | |
1262 | do_nologin(struct passwd *pw) | |
1263 | { | |
1264 | FILE *f = NULL; | |
1265 | char buf[1024]; | |
1266 | ||
1267 | #ifdef HAVE_LOGIN_CAP | |
1268 | if (!login_getcapbool(lc, "ignorenologin", 0) && pw->pw_uid) | |
1269 | f = fopen(login_getcapstr(lc, "nologin", _PATH_NOLOGIN, | |
1270 | _PATH_NOLOGIN), "r"); | |
1271 | #else | |
1272 | if (pw->pw_uid) | |
1273 | f = fopen(_PATH_NOLOGIN, "r"); | |
1274 | #endif | |
1275 | if (f) { | |
1276 | /* /etc/nologin exists. Print its contents and exit. */ | |
1277 | logit("User %.100s not allowed because %s exists", | |
1278 | pw->pw_name, _PATH_NOLOGIN); | |
1279 | while (fgets(buf, sizeof(buf), f)) | |
1280 | fputs(buf, stderr); | |
1281 | fclose(f); | |
1282 | fflush(NULL); | |
1283 | exit(254); | |
1284 | } | |
1285 | } | |
1286 | ||
1287 | /* | |
1288 | * Chroot into a directory after checking it for safety: all path components | |
1289 | * must be root-owned directories with strict permissions. | |
1290 | */ | |
1291 | static void | |
1292 | safely_chroot(const char *path, uid_t uid) | |
1293 | { | |
1294 | const char *cp; | |
1295 | char component[MAXPATHLEN]; | |
1296 | struct stat st; | |
1297 | ||
1298 | if (*path != '/') | |
1299 | fatal("chroot path does not begin at root"); | |
1300 | if (strlen(path) >= sizeof(component)) | |
1301 | fatal("chroot path too long"); | |
1302 | ||
1303 | /* | |
1304 | * Descend the path, checking that each component is a | |
1305 | * root-owned directory with strict permissions. | |
1306 | */ | |
1307 | for (cp = path; cp != NULL;) { | |
1308 | if ((cp = strchr(cp, '/')) == NULL) | |
1309 | strlcpy(component, path, sizeof(component)); | |
1310 | else { | |
1311 | cp++; | |
1312 | memcpy(component, path, cp - path); | |
1313 | component[cp - path] = '\0'; | |
1314 | } | |
1315 | ||
1316 | debug3("%s: checking '%s'", __func__, component); | |
1317 | ||
1318 | if (stat(component, &st) != 0) | |
1319 | fatal("%s: stat(\"%s\"): %s", __func__, | |
1320 | component, strerror(errno)); | |
1321 | if (st.st_uid != 0 || (st.st_mode & 022) != 0) | |
1322 | fatal("bad ownership or modes for chroot " | |
1323 | "directory %s\"%s\"", | |
1324 | cp == NULL ? "" : "component ", component); | |
1325 | if (!S_ISDIR(st.st_mode)) | |
1326 | fatal("chroot path %s\"%s\" is not a directory", | |
1327 | cp == NULL ? "" : "component ", component); | |
1328 | ||
1329 | } | |
1330 | ||
1331 | if (chdir(path) == -1) | |
1332 | fatal("Unable to chdir to chroot path \"%s\": " | |
1333 | "%s", path, strerror(errno)); | |
1334 | if (chroot(path) == -1) | |
1335 | fatal("chroot(\"%s\"): %s", path, strerror(errno)); | |
1336 | if (chdir("/") == -1) | |
1337 | fatal("%s: chdir(/) after chroot: %s", | |
1338 | __func__, strerror(errno)); | |
1339 | verbose("Changed root directory to \"%s\"", path); | |
1340 | } | |
1341 | ||
1342 | /* Set login name, uid, gid, and groups. */ | |
1343 | void | |
1344 | do_setusercontext(struct passwd *pw) | |
1345 | { | |
1346 | char *chroot_path, *tmp; | |
1347 | ||
1348 | #ifndef HAVE_CYGWIN | |
1349 | if (getuid() == 0 || geteuid() == 0) | |
1350 | #endif /* HAVE_CYGWIN */ | |
1351 | { | |
1352 | ||
1353 | #ifdef HAVE_SETPCRED | |
1354 | if (setpcred(pw->pw_name, (char **)NULL) == -1) | |
1355 | fatal("Failed to set process credentials"); | |
1356 | #endif /* HAVE_SETPCRED */ | |
1357 | #ifdef HAVE_LOGIN_CAP | |
1358 | # ifdef __bsdi__ | |
1359 | setpgid(0, 0); | |
1360 | # endif | |
1361 | # ifdef USE_PAM | |
1362 | if (options.use_pam) { | |
1363 | do_pam_setcred(use_privsep); | |
1364 | } | |
1365 | # endif /* USE_PAM */ | |
1366 | if (setusercontext(lc, pw, pw->pw_uid, | |
1367 | (LOGIN_SETALL & ~(LOGIN_SETPATH|LOGIN_SETUSER))) < 0) { | |
1368 | perror("unable to set user context"); | |
1369 | exit(1); | |
1370 | } | |
1371 | #else | |
1372 | # if defined(HAVE_GETLUID) && defined(HAVE_SETLUID) | |
1373 | /* Sets login uid for accounting */ | |
1374 | if (getluid() == -1 && setluid(pw->pw_uid) == -1) | |
1375 | error("setluid: %s", strerror(errno)); | |
1376 | # endif /* defined(HAVE_GETLUID) && defined(HAVE_SETLUID) */ | |
1377 | ||
1378 | if (setlogin(pw->pw_name) < 0) | |
1379 | error("setlogin failed: %s", strerror(errno)); | |
1380 | if (setgid(pw->pw_gid) < 0) { | |
1381 | perror("setgid"); | |
1382 | exit(1); | |
1383 | } | |
1384 | /* Initialize the group list. */ | |
1385 | if (initgroups(pw->pw_name, pw->pw_gid) < 0) { | |
1386 | perror("initgroups"); | |
1387 | exit(1); | |
1388 | } | |
1389 | endgrent(); | |
1390 | # ifdef USE_PAM | |
1391 | /* | |
1392 | * PAM credentials may take the form of supplementary groups. | |
1393 | * These will have been wiped by the above initgroups() call. | |
1394 | * Reestablish them here. | |
1395 | */ | |
1396 | if (options.use_pam) { | |
1397 | do_pam_setcred(use_privsep); | |
1398 | } | |
1399 | # endif /* USE_PAM */ | |
1400 | # if defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) | |
1401 | irix_setusercontext(pw); | |
1402 | # endif /* defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) */ | |
1403 | # ifdef _AIX | |
1404 | aix_usrinfo(pw); | |
1405 | # endif /* _AIX */ | |
1406 | # ifdef USE_LIBIAF | |
1407 | if (set_id(pw->pw_name) != 0) { | |
1408 | exit(1); | |
1409 | } | |
1410 | # endif /* USE_LIBIAF */ | |
1411 | #endif | |
1412 | ||
1413 | if (options.chroot_directory != NULL && | |
1414 | strcasecmp(options.chroot_directory, "none") != 0) { | |
1415 | tmp = tilde_expand_filename(options.chroot_directory, | |
1416 | pw->pw_uid); | |
1417 | chroot_path = percent_expand(tmp, "h", pw->pw_dir, | |
1418 | "u", pw->pw_name, (char *)NULL); | |
1419 | safely_chroot(chroot_path, pw->pw_uid); | |
1420 | free(tmp); | |
1421 | free(chroot_path); | |
1422 | } | |
1423 | ||
1424 | #ifdef HAVE_LOGIN_CAP | |
1425 | if (setusercontext(lc, pw, pw->pw_uid, LOGIN_SETUSER) < 0) { | |
1426 | perror("unable to set user context (setuser)"); | |
1427 | exit(1); | |
1428 | } | |
1429 | #else | |
1430 | /* Permanently switch to the desired uid. */ | |
1431 | permanently_set_uid(pw); | |
1432 | #endif | |
1433 | } | |
1434 | ||
1435 | #ifdef HAVE_CYGWIN | |
1436 | if (is_winnt) | |
1437 | #endif | |
1438 | if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid) | |
1439 | fatal("Failed to set uids to %u.", (u_int) pw->pw_uid); | |
1440 | ||
1441 | #ifdef WITH_SELINUX | |
1442 | ssh_selinux_setup_exec_context(pw->pw_name); | |
1443 | #endif | |
1444 | } | |
1445 | ||
1446 | static void | |
1447 | do_pwchange(Session *s) | |
1448 | { | |
1449 | fflush(NULL); | |
1450 | fprintf(stderr, "WARNING: Your password has expired.\n"); | |
1451 | if (s->ttyfd != -1) { | |
1452 | fprintf(stderr, | |
1453 | "You must change your password now and login again!\n"); | |
1454 | #ifdef PASSWD_NEEDS_USERNAME | |
1455 | execl(_PATH_PASSWD_PROG, "passwd", s->pw->pw_name, | |
1456 | (char *)NULL); | |
1457 | #else | |
1458 | execl(_PATH_PASSWD_PROG, "passwd", (char *)NULL); | |
1459 | #endif | |
1460 | perror("passwd"); | |
1461 | } else { | |
1462 | fprintf(stderr, | |
1463 | "Password change required but no TTY available.\n"); | |
1464 | } | |
1465 | exit(1); | |
1466 | } | |
1467 | ||
1468 | static void | |
1469 | launch_login(struct passwd *pw, const char *hostname) | |
1470 | { | |
1471 | /* Launch login(1). */ | |
1472 | ||
1473 | execl(LOGIN_PROGRAM, "login", "-h", hostname, | |
1474 | #ifdef xxxLOGIN_NEEDS_TERM | |
1475 | (s->term ? s->term : "unknown"), | |
1476 | #endif /* LOGIN_NEEDS_TERM */ | |
1477 | #ifdef LOGIN_NO_ENDOPT | |
1478 | "-p", "-f", pw->pw_name, (char *)NULL); | |
1479 | #else | |
1480 | "-p", "-f", "--", pw->pw_name, (char *)NULL); | |
1481 | #endif | |
1482 | ||
1483 | /* Login couldn't be executed, die. */ | |
1484 | ||
1485 | perror("login"); | |
1486 | exit(1); | |
1487 | } | |
1488 | ||
1489 | static void | |
1490 | child_close_fds(void) | |
1491 | { | |
1492 | int i; | |
1493 | ||
1494 | if (packet_get_connection_in() == packet_get_connection_out()) | |
1495 | close(packet_get_connection_in()); | |
1496 | else { | |
1497 | close(packet_get_connection_in()); | |
1498 | close(packet_get_connection_out()); | |
1499 | } | |
1500 | /* | |
1501 | * Close all descriptors related to channels. They will still remain | |
1502 | * open in the parent. | |
1503 | */ | |
1504 | /* XXX better use close-on-exec? -markus */ | |
1505 | channel_close_all(); | |
1506 | ||
1507 | /* | |
1508 | * Close any extra file descriptors. Note that there may still be | |
1509 | * descriptors left by system functions. They will be closed later. | |
1510 | */ | |
1511 | endpwent(); | |
1512 | ||
1513 | /* | |
1514 | * Close any extra open file descriptors so that we don't have them | |
1515 | * hanging around in clients. Note that we want to do this after | |
1516 | * initgroups, because at least on Solaris 2.3 it leaves file | |
1517 | * descriptors open. | |
1518 | */ | |
1519 | for (i = 3; i < 64; i++) | |
1520 | close(i); | |
1521 | } | |
1522 | ||
1523 | /* | |
1524 | * Performs common processing for the child, such as setting up the | |
1525 | * environment, closing extra file descriptors, setting the user and group | |
1526 | * ids, and executing the command or shell. | |
1527 | */ | |
1528 | #define ARGV_MAX 10 | |
1529 | void | |
1530 | do_child(Session *s, const char *command) | |
1531 | { | |
1532 | extern char **environ; | |
1533 | char **env; | |
1534 | char *argv[ARGV_MAX]; | |
1535 | const char *shell, *shell0, *hostname = NULL; | |
1536 | struct passwd *pw = s->pw; | |
1537 | ||
1538 | /* remove hostkey from the child's memory */ | |
1539 | destroy_sensitive_data(); | |
1540 | ||
1541 | /* Force a password change */ | |
1542 | if (s->authctxt->force_pwchange) { | |
1543 | do_setusercontext(pw); | |
1544 | child_close_fds(); | |
1545 | do_pwchange(s); | |
1546 | exit(1); | |
1547 | } | |
1548 | ||
1549 | /* login(1) is only called if we execute the login shell */ | |
1550 | if (options.use_login && command != NULL) | |
1551 | options.use_login = 0; | |
1552 | ||
1553 | #ifdef _UNICOS | |
1554 | cray_setup(pw->pw_uid, pw->pw_name, command); | |
1555 | #endif /* _UNICOS */ | |
1556 | ||
1557 | /* | |
1558 | * Login(1) does this as well, and it needs uid 0 for the "-h" | |
1559 | * switch, so we let login(1) to this for us. | |
1560 | */ | |
1561 | if (!options.use_login) { | |
1562 | #ifdef HAVE_OSF_SIA | |
1563 | session_setup_sia(pw, s->ttyfd == -1 ? NULL : s->tty); | |
1564 | if (!check_quietlogin(s, command)) | |
1565 | do_motd(); | |
1566 | #else /* HAVE_OSF_SIA */ | |
1567 | /* When PAM is enabled we rely on it to do the nologin check */ | |
1568 | if (!options.use_pam) | |
1569 | do_nologin(pw); | |
1570 | do_setusercontext(pw); | |
1571 | /* | |
1572 | * PAM session modules in do_setusercontext may have | |
1573 | * generated messages, so if this in an interactive | |
1574 | * login then display them too. | |
1575 | */ | |
1576 | if (!check_quietlogin(s, command)) | |
1577 | display_loginmsg(); | |
1578 | #endif /* HAVE_OSF_SIA */ | |
1579 | } | |
1580 | ||
1581 | #ifdef USE_PAM | |
1582 | if (options.use_pam && !options.use_login && !is_pam_session_open()) { | |
1583 | debug3("PAM session not opened, exiting"); | |
1584 | display_loginmsg(); | |
1585 | exit(254); | |
1586 | } | |
1587 | #endif | |
1588 | ||
1589 | /* | |
1590 | * Get the shell from the password data. An empty shell field is | |
1591 | * legal, and means /bin/sh. | |
1592 | */ | |
1593 | shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell; | |
1594 | ||
1595 | /* | |
1596 | * Make sure $SHELL points to the shell from the password file, | |
1597 | * even if shell is overridden from login.conf | |
1598 | */ | |
1599 | env = do_setup_env(s, shell); | |
1600 | ||
1601 | #ifdef HAVE_LOGIN_CAP | |
1602 | shell = login_getcapstr(lc, "shell", (char *)shell, (char *)shell); | |
1603 | #endif | |
1604 | ||
1605 | /* we have to stash the hostname before we close our socket. */ | |
1606 | if (options.use_login) | |
1607 | hostname = get_remote_name_or_ip(utmp_len, | |
1608 | options.use_dns); | |
1609 | /* | |
1610 | * Close the connection descriptors; note that this is the child, and | |
1611 | * the server will still have the socket open, and it is important | |
1612 | * that we do not shutdown it. Note that the descriptors cannot be | |
1613 | * closed before building the environment, as we call | |
1614 | * get_remote_ipaddr there. | |
1615 | */ | |
1616 | child_close_fds(); | |
1617 | ||
1618 | /* | |
1619 | * Must take new environment into use so that .ssh/rc, | |
1620 | * /etc/ssh/sshrc and xauth are run in the proper environment. | |
1621 | */ | |
1622 | environ = env; | |
1623 | ||
1624 | #if defined(KRB5) && defined(USE_AFS) | |
1625 | /* | |
1626 | * At this point, we check to see if AFS is active and if we have | |
1627 | * a valid Kerberos 5 TGT. If so, it seems like a good idea to see | |
1628 | * if we can (and need to) extend the ticket into an AFS token. If | |
1629 | * we don't do this, we run into potential problems if the user's | |
1630 | * home directory is in AFS and it's not world-readable. | |
1631 | */ | |
1632 | ||
1633 | if (options.kerberos_get_afs_token && k_hasafs() && | |
1634 | (s->authctxt->krb5_ctx != NULL)) { | |
1635 | char cell[64]; | |
1636 | ||
1637 | debug("Getting AFS token"); | |
1638 | ||
1639 | k_setpag(); | |
1640 | ||
1641 | if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0) | |
1642 | krb5_afslog(s->authctxt->krb5_ctx, | |
1643 | s->authctxt->krb5_fwd_ccache, cell, NULL); | |
1644 | ||
1645 | krb5_afslog_home(s->authctxt->krb5_ctx, | |
1646 | s->authctxt->krb5_fwd_ccache, NULL, NULL, pw->pw_dir); | |
1647 | } | |
1648 | #endif | |
1649 | ||
1650 | /* Change current directory to the user's home directory. */ | |
1651 | if (chdir(pw->pw_dir) < 0) { | |
1652 | fprintf(stderr, "Could not chdir to home directory %s: %s\n", | |
1653 | pw->pw_dir, strerror(errno)); | |
1654 | #ifdef HAVE_LOGIN_CAP | |
1655 | if (login_getcapbool(lc, "requirehome", 0)) | |
1656 | exit(1); | |
1657 | #endif | |
1658 | } | |
1659 | ||
1660 | closefrom(STDERR_FILENO + 1); | |
1661 | ||
1662 | if (!options.use_login) | |
1663 | do_rc_files(s, shell); | |
1664 | ||
1665 | /* restore SIGPIPE for child */ | |
1666 | signal(SIGPIPE, SIG_DFL); | |
1667 | ||
1668 | if (s->is_subsystem == SUBSYSTEM_INT_SFTP) { | |
1669 | extern int optind, optreset; | |
1670 | int i; | |
1671 | char *p, *args; | |
1672 | ||
1673 | setproctitle("%s@internal-sftp-server", s->pw->pw_name); | |
1674 | args = strdup(command ? command : "sftp-server"); | |
1675 | for (i = 0, (p = strtok(args, " ")); p; (p = strtok(NULL, " "))) | |
1676 | if (i < ARGV_MAX - 1) | |
1677 | argv[i++] = p; | |
1678 | argv[i] = NULL; | |
1679 | optind = optreset = 1; | |
1680 | __progname = argv[0]; | |
1681 | exit(sftp_server_main(i, argv, s->pw)); | |
1682 | } | |
1683 | ||
1684 | if (options.use_login) { | |
1685 | launch_login(pw, hostname); | |
1686 | /* NEVERREACHED */ | |
1687 | } | |
1688 | ||
1689 | /* Get the last component of the shell name. */ | |
1690 | if ((shell0 = strrchr(shell, '/')) != NULL) | |
1691 | shell0++; | |
1692 | else | |
1693 | shell0 = shell; | |
1694 | ||
1695 | /* | |
1696 | * If we have no command, execute the shell. In this case, the shell | |
1697 | * name to be passed in argv[0] is preceded by '-' to indicate that | |
1698 | * this is a login shell. | |
1699 | */ | |
1700 | if (!command) { | |
1701 | char argv0[256]; | |
1702 | ||
1703 | /* Start the shell. Set initial character to '-'. */ | |
1704 | argv0[0] = '-'; | |
1705 | ||
1706 | if (strlcpy(argv0 + 1, shell0, sizeof(argv0) - 1) | |
1707 | >= sizeof(argv0) - 1) { | |
1708 | errno = EINVAL; | |
1709 | perror(shell); | |
1710 | exit(1); | |
1711 | } | |
1712 | ||
1713 | /* Execute the shell. */ | |
1714 | argv[0] = argv0; | |
1715 | argv[1] = NULL; | |
1716 | execve(shell, argv, env); | |
1717 | ||
1718 | /* Executing the shell failed. */ | |
1719 | perror(shell); | |
1720 | exit(1); | |
1721 | } | |
1722 | /* | |
1723 | * Execute the command using the user's shell. This uses the -c | |
1724 | * option to execute the command. | |
1725 | */ | |
1726 | argv[0] = (char *) shell0; | |
1727 | argv[1] = "-c"; | |
1728 | argv[2] = (char *) command; | |
1729 | argv[3] = NULL; | |
1730 | execve(shell, argv, env); | |
1731 | perror(shell); | |
1732 | exit(1); | |
1733 | } | |
1734 | ||
1735 | Session * | |
1736 | session_new(void) | |
1737 | { | |
1738 | int i; | |
1739 | static int did_init = 0; | |
1740 | if (!did_init) { | |
1741 | debug("session_new: init"); | |
1742 | for (i = 0; i < MAX_SESSIONS; i++) { | |
1743 | sessions[i].used = 0; | |
1744 | } | |
1745 | did_init = 1; | |
1746 | } | |
1747 | for (i = 0; i < MAX_SESSIONS; i++) { | |
1748 | Session *s = &sessions[i]; | |
1749 | if (! s->used) { | |
1750 | memset(s, 0, sizeof(*s)); | |
1751 | s->chanid = -1; | |
1752 | s->ptyfd = -1; | |
1753 | s->ttyfd = -1; | |
1754 | s->used = 1; | |
1755 | s->self = i; | |
1756 | s->x11_chanids = NULL; | |
1757 | debug("session_new: session %d", i); | |
1758 | return s; | |
1759 | } | |
1760 | } | |
1761 | return NULL; | |
1762 | } | |
1763 | ||
1764 | static void | |
1765 | session_dump(void) | |
1766 | { | |
1767 | int i; | |
1768 | for (i = 0; i < MAX_SESSIONS; i++) { | |
1769 | Session *s = &sessions[i]; | |
1770 | debug("dump: used %d session %d %p channel %d pid %ld", | |
1771 | s->used, | |
1772 | s->self, | |
1773 | s, | |
1774 | s->chanid, | |
1775 | (long)s->pid); | |
1776 | } | |
1777 | } | |
1778 | ||
1779 | int | |
1780 | session_open(Authctxt *authctxt, int chanid) | |
1781 | { | |
1782 | Session *s = session_new(); | |
1783 | debug("session_open: channel %d", chanid); | |
1784 | if (s == NULL) { | |
1785 | error("no more sessions"); | |
1786 | return 0; | |
1787 | } | |
1788 | s->authctxt = authctxt; | |
1789 | s->pw = authctxt->pw; | |
1790 | if (s->pw == NULL || !authctxt->valid) | |
1791 | fatal("no user for session %d", s->self); | |
1792 | debug("session_open: session %d: link with channel %d", s->self, chanid); | |
1793 | s->chanid = chanid; | |
1794 | return 1; | |
1795 | } | |
1796 | ||
1797 | Session * | |
1798 | session_by_tty(char *tty) | |
1799 | { | |
1800 | int i; | |
1801 | for (i = 0; i < MAX_SESSIONS; i++) { | |
1802 | Session *s = &sessions[i]; | |
1803 | if (s->used && s->ttyfd != -1 && strcmp(s->tty, tty) == 0) { | |
1804 | debug("session_by_tty: session %d tty %s", i, tty); | |
1805 | return s; | |
1806 | } | |
1807 | } | |
1808 | debug("session_by_tty: unknown tty %.100s", tty); | |
1809 | session_dump(); | |
1810 | return NULL; | |
1811 | } | |
1812 | ||
1813 | static Session * | |
1814 | session_by_channel(int id) | |
1815 | { | |
1816 | int i; | |
1817 | for (i = 0; i < MAX_SESSIONS; i++) { | |
1818 | Session *s = &sessions[i]; | |
1819 | if (s->used && s->chanid == id) { | |
1820 | debug("session_by_channel: session %d channel %d", i, id); | |
1821 | return s; | |
1822 | } | |
1823 | } | |
1824 | debug("session_by_channel: unknown channel %d", id); | |
1825 | session_dump(); | |
1826 | return NULL; | |
1827 | } | |
1828 | ||
1829 | static Session * | |
1830 | session_by_x11_channel(int id) | |
1831 | { | |
1832 | int i, j; | |
1833 | ||
1834 | for (i = 0; i < MAX_SESSIONS; i++) { | |
1835 | Session *s = &sessions[i]; | |
1836 | ||
1837 | if (s->x11_chanids == NULL || !s->used) | |
1838 | continue; | |
1839 | for (j = 0; s->x11_chanids[j] != -1; j++) { | |
1840 | if (s->x11_chanids[j] == id) { | |
1841 | debug("session_by_x11_channel: session %d " | |
1842 | "channel %d", s->self, id); | |
1843 | return s; | |
1844 | } | |
1845 | } | |
1846 | } | |
1847 | debug("session_by_x11_channel: unknown channel %d", id); | |
1848 | session_dump(); | |
1849 | return NULL; | |
1850 | } | |
1851 | ||
1852 | static Session * | |
1853 | session_by_pid(pid_t pid) | |
1854 | { | |
1855 | int i; | |
1856 | debug("session_by_pid: pid %ld", (long)pid); | |
1857 | for (i = 0; i < MAX_SESSIONS; i++) { | |
1858 | Session *s = &sessions[i]; | |
1859 | if (s->used && s->pid == pid) | |
1860 | return s; | |
1861 | } | |
1862 | error("session_by_pid: unknown pid %ld", (long)pid); | |
1863 | session_dump(); | |
1864 | return NULL; | |
1865 | } | |
1866 | ||
1867 | static int | |
1868 | session_window_change_req(Session *s) | |
1869 | { | |
1870 | s->col = packet_get_int(); | |
1871 | s->row = packet_get_int(); | |
1872 | s->xpixel = packet_get_int(); | |
1873 | s->ypixel = packet_get_int(); | |
1874 | packet_check_eom(); | |
1875 | pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel); | |
1876 | return 1; | |
1877 | } | |
1878 | ||
1879 | static int | |
1880 | session_pty_req(Session *s) | |
1881 | { | |
1882 | u_int len; | |
1883 | int n_bytes; | |
1884 | ||
1885 | if (no_pty_flag) { | |
1886 | debug("Allocating a pty not permitted for this authentication."); | |
1887 | return 0; | |
1888 | } | |
1889 | if (s->ttyfd != -1) { | |
1890 | packet_disconnect("Protocol error: you already have a pty."); | |
1891 | return 0; | |
1892 | } | |
1893 | ||
1894 | s->term = packet_get_string(&len); | |
1895 | ||
1896 | if (compat20) { | |
1897 | s->col = packet_get_int(); | |
1898 | s->row = packet_get_int(); | |
1899 | } else { | |
1900 | s->row = packet_get_int(); | |
1901 | s->col = packet_get_int(); | |
1902 | } | |
1903 | s->xpixel = packet_get_int(); | |
1904 | s->ypixel = packet_get_int(); | |
1905 | ||
1906 | if (strcmp(s->term, "") == 0) { | |
1907 | xfree(s->term); | |
1908 | s->term = NULL; | |
1909 | } | |
1910 | ||
1911 | /* Allocate a pty and open it. */ | |
1912 | debug("Allocating pty."); | |
1913 | if (!PRIVSEP(pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty)))) { | |
1914 | if (s->term) | |
1915 | xfree(s->term); | |
1916 | s->term = NULL; | |
1917 | s->ptyfd = -1; | |
1918 | s->ttyfd = -1; | |
1919 | error("session_pty_req: session %d alloc failed", s->self); | |
1920 | return 0; | |
1921 | } | |
1922 | debug("session_pty_req: session %d alloc %s", s->self, s->tty); | |
1923 | ||
1924 | /* for SSH1 the tty modes length is not given */ | |
1925 | if (!compat20) | |
1926 | n_bytes = packet_remaining(); | |
1927 | tty_parse_modes(s->ttyfd, &n_bytes); | |
1928 | ||
1929 | if (!use_privsep) | |
1930 | pty_setowner(s->pw, s->tty); | |
1931 | ||
1932 | /* Set window size from the packet. */ | |
1933 | pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel); | |
1934 | ||
1935 | packet_check_eom(); | |
1936 | session_proctitle(s); | |
1937 | return 1; | |
1938 | } | |
1939 | ||
1940 | static int | |
1941 | session_subsystem_req(Session *s) | |
1942 | { | |
1943 | struct stat st; | |
1944 | u_int len; | |
1945 | int success = 0; | |
1946 | char *prog, *cmd, *subsys = packet_get_string(&len); | |
1947 | u_int i; | |
1948 | ||
1949 | packet_check_eom(); | |
1950 | logit("subsystem request for %.100s", subsys); | |
1951 | ||
1952 | for (i = 0; i < options.num_subsystems; i++) { | |
1953 | if (strcmp(subsys, options.subsystem_name[i]) == 0) { | |
1954 | prog = options.subsystem_command[i]; | |
1955 | cmd = options.subsystem_args[i]; | |
1956 | if (!strcmp(INTERNAL_SFTP_NAME, prog)) { | |
1957 | s->is_subsystem = SUBSYSTEM_INT_SFTP; | |
1958 | } else if (stat(prog, &st) < 0) { | |
1959 | error("subsystem: cannot stat %s: %s", prog, | |
1960 | strerror(errno)); | |
1961 | break; | |
1962 | } else { | |
1963 | s->is_subsystem = SUBSYSTEM_EXT; | |
1964 | } | |
1965 | debug("subsystem: exec() %s", cmd); | |
1966 | do_exec(s, cmd); | |
1967 | success = 1; | |
1968 | break; | |
1969 | } | |
1970 | } | |
1971 | ||
1972 | if (!success) | |
1973 | logit("subsystem request for %.100s failed, subsystem not found", | |
1974 | subsys); | |
1975 | ||
1976 | xfree(subsys); | |
1977 | return success; | |
1978 | } | |
1979 | ||
1980 | static int | |
1981 | session_x11_req(Session *s) | |
1982 | { | |
1983 | int success; | |
1984 | ||
1985 | if (s->auth_proto != NULL || s->auth_data != NULL) { | |
1986 | error("session_x11_req: session %d: " | |
1987 | "x11 forwarding already active", s->self); | |
1988 | return 0; | |
1989 | } | |
1990 | s->single_connection = packet_get_char(); | |
1991 | s->auth_proto = packet_get_string(NULL); | |
1992 | s->auth_data = packet_get_string(NULL); | |
1993 | s->screen = packet_get_int(); | |
1994 | packet_check_eom(); | |
1995 | ||
1996 | success = session_setup_x11fwd(s); | |
1997 | if (!success) { | |
1998 | xfree(s->auth_proto); | |
1999 | xfree(s->auth_data); | |
2000 | s->auth_proto = NULL; | |
2001 | s->auth_data = NULL; | |
2002 | } | |
2003 | return success; | |
2004 | } | |
2005 | ||
2006 | static int | |
2007 | session_shell_req(Session *s) | |
2008 | { | |
2009 | packet_check_eom(); | |
2010 | do_exec(s, NULL); | |
2011 | return 1; | |
2012 | } | |
2013 | ||
2014 | static int | |
2015 | session_exec_req(Session *s) | |
2016 | { | |
2017 | u_int len; | |
2018 | char *command = packet_get_string(&len); | |
2019 | packet_check_eom(); | |
2020 | do_exec(s, command); | |
2021 | xfree(command); | |
2022 | return 1; | |
2023 | } | |
2024 | ||
2025 | static int | |
2026 | session_break_req(Session *s) | |
2027 | { | |
2028 | ||
2029 | packet_get_int(); /* ignored */ | |
2030 | packet_check_eom(); | |
2031 | ||
2032 | if (s->ttyfd == -1 || | |
2033 | tcsendbreak(s->ttyfd, 0) < 0) | |
2034 | return 0; | |
2035 | return 1; | |
2036 | } | |
2037 | ||
2038 | static int | |
2039 | session_env_req(Session *s) | |
2040 | { | |
2041 | char *name, *val; | |
2042 | u_int name_len, val_len, i; | |
2043 | ||
2044 | name = packet_get_string(&name_len); | |
2045 | val = packet_get_string(&val_len); | |
2046 | packet_check_eom(); | |
2047 | ||
2048 | /* Don't set too many environment variables */ | |
2049 | if (s->num_env > 128) { | |
2050 | debug2("Ignoring env request %s: too many env vars", name); | |
2051 | goto fail; | |
2052 | } | |
2053 | ||
2054 | for (i = 0; i < options.num_accept_env; i++) { | |
2055 | if (match_pattern(name, options.accept_env[i])) { | |
2056 | debug2("Setting env %d: %s=%s", s->num_env, name, val); | |
2057 | s->env = xrealloc(s->env, s->num_env + 1, | |
2058 | sizeof(*s->env)); | |
2059 | s->env[s->num_env].name = name; | |
2060 | s->env[s->num_env].val = val; | |
2061 | s->num_env++; | |
2062 | return (1); | |
2063 | } | |
2064 | } | |
2065 | debug2("Ignoring env request %s: disallowed name", name); | |
2066 | ||
2067 | fail: | |
2068 | xfree(name); | |
2069 | xfree(val); | |
2070 | return (0); | |
2071 | } | |
2072 | ||
2073 | static int | |
2074 | session_auth_agent_req(Session *s) | |
2075 | { | |
2076 | static int called = 0; | |
2077 | packet_check_eom(); | |
2078 | if (no_agent_forwarding_flag) { | |
2079 | debug("session_auth_agent_req: no_agent_forwarding_flag"); | |
2080 | return 0; | |
2081 | } | |
2082 | if (called) { | |
2083 | return 0; | |
2084 | } else { | |
2085 | called = 1; | |
2086 | return auth_input_request_forwarding(s->pw); | |
2087 | } | |
2088 | } | |
2089 | ||
2090 | int | |
2091 | session_input_channel_req(Channel *c, const char *rtype) | |
2092 | { | |
2093 | int success = 0; | |
2094 | Session *s; | |
2095 | ||
2096 | if ((s = session_by_channel(c->self)) == NULL) { | |
2097 | logit("session_input_channel_req: no session %d req %.100s", | |
2098 | c->self, rtype); | |
2099 | return 0; | |
2100 | } | |
2101 | debug("session_input_channel_req: session %d req %s", s->self, rtype); | |
2102 | ||
2103 | /* | |
2104 | * a session is in LARVAL state until a shell, a command | |
2105 | * or a subsystem is executed | |
2106 | */ | |
2107 | if (c->type == SSH_CHANNEL_LARVAL) { | |
2108 | if (strcmp(rtype, "shell") == 0) { | |
2109 | success = session_shell_req(s); | |
2110 | } else if (strcmp(rtype, "exec") == 0) { | |
2111 | success = session_exec_req(s); | |
2112 | } else if (strcmp(rtype, "pty-req") == 0) { | |
2113 | success = session_pty_req(s); | |
2114 | } else if (strcmp(rtype, "x11-req") == 0) { | |
2115 | success = session_x11_req(s); | |
2116 | } else if (strcmp(rtype, "auth-agent-req@openssh.com") == 0) { | |
2117 | success = session_auth_agent_req(s); | |
2118 | } else if (strcmp(rtype, "subsystem") == 0) { | |
2119 | success = session_subsystem_req(s); | |
2120 | } else if (strcmp(rtype, "env") == 0) { | |
2121 | success = session_env_req(s); | |
2122 | } | |
2123 | } | |
2124 | if (strcmp(rtype, "window-change") == 0) { | |
2125 | success = session_window_change_req(s); | |
2126 | } else if (strcmp(rtype, "break") == 0) { | |
2127 | success = session_break_req(s); | |
2128 | } | |
2129 | ||
2130 | return success; | |
2131 | } | |
2132 | ||
2133 | void | |
2134 | session_set_fds(Session *s, int fdin, int fdout, int fderr) | |
2135 | { | |
2136 | if (!compat20) | |
2137 | fatal("session_set_fds: called for proto != 2.0"); | |
2138 | /* | |
2139 | * now that have a child and a pipe to the child, | |
2140 | * we can activate our channel and register the fd's | |
2141 | */ | |
2142 | if (s->chanid == -1) | |
2143 | fatal("no channel for session %d", s->self); | |
2144 | channel_set_fds(s->chanid, | |
2145 | fdout, fdin, fderr, | |
2146 | fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ, | |
2147 | 1, | |
2148 | CHAN_SES_WINDOW_DEFAULT); | |
2149 | } | |
2150 | ||
2151 | /* | |
2152 | * Function to perform pty cleanup. Also called if we get aborted abnormally | |
2153 | * (e.g., due to a dropped connection). | |
2154 | */ | |
2155 | void | |
2156 | session_pty_cleanup2(Session *s) | |
2157 | { | |
2158 | if (s == NULL) { | |
2159 | error("session_pty_cleanup: no session"); | |
2160 | return; | |
2161 | } | |
2162 | if (s->ttyfd == -1) | |
2163 | return; | |
2164 | ||
2165 | debug("session_pty_cleanup: session %d release %s", s->self, s->tty); | |
2166 | ||
2167 | /* Record that the user has logged out. */ | |
2168 | if (s->pid != 0) | |
2169 | record_logout(s->pid, s->tty, s->pw->pw_name); | |
2170 | ||
2171 | /* Release the pseudo-tty. */ | |
2172 | if (getuid() == 0) | |
2173 | pty_release(s->tty); | |
2174 | ||
2175 | /* | |
2176 | * Close the server side of the socket pairs. We must do this after | |
2177 | * the pty cleanup, so that another process doesn't get this pty | |
2178 | * while we're still cleaning up. | |
2179 | */ | |
2180 | if (close(s->ptymaster) < 0) | |
2181 | error("close(s->ptymaster/%d): %s", s->ptymaster, strerror(errno)); | |
2182 | ||
2183 | /* unlink pty from session */ | |
2184 | s->ttyfd = -1; | |
2185 | } | |
2186 | ||
2187 | void | |
2188 | session_pty_cleanup(Session *s) | |
2189 | { | |
2190 | PRIVSEP(session_pty_cleanup2(s)); | |
2191 | } | |
2192 | ||
2193 | static char * | |
2194 | sig2name(int sig) | |
2195 | { | |
2196 | #define SSH_SIG(x) if (sig == SIG ## x) return #x | |
2197 | SSH_SIG(ABRT); | |
2198 | SSH_SIG(ALRM); | |
2199 | SSH_SIG(FPE); | |
2200 | SSH_SIG(HUP); | |
2201 | SSH_SIG(ILL); | |
2202 | SSH_SIG(INT); | |
2203 | SSH_SIG(KILL); | |
2204 | SSH_SIG(PIPE); | |
2205 | SSH_SIG(QUIT); | |
2206 | SSH_SIG(SEGV); | |
2207 | SSH_SIG(TERM); | |
2208 | SSH_SIG(USR1); | |
2209 | SSH_SIG(USR2); | |
2210 | #undef SSH_SIG | |
2211 | return "SIG@openssh.com"; | |
2212 | } | |
2213 | ||
2214 | static void | |
2215 | session_close_x11(int id) | |
2216 | { | |
2217 | Channel *c; | |
2218 | ||
2219 | if ((c = channel_by_id(id)) == NULL) { | |
2220 | debug("session_close_x11: x11 channel %d missing", id); | |
2221 | } else { | |
2222 | /* Detach X11 listener */ | |
2223 | debug("session_close_x11: detach x11 channel %d", id); | |
2224 | channel_cancel_cleanup(id); | |
2225 | if (c->ostate != CHAN_OUTPUT_CLOSED) | |
2226 | chan_mark_dead(c); | |
2227 | } | |
2228 | } | |
2229 | ||
2230 | static void | |
2231 | session_close_single_x11(int id, void *arg) | |
2232 | { | |
2233 | Session *s; | |
2234 | u_int i; | |
2235 | ||
2236 | debug3("session_close_single_x11: channel %d", id); | |
2237 | channel_cancel_cleanup(id); | |
2238 | if ((s = session_by_x11_channel(id)) == NULL) | |
2239 | fatal("session_close_single_x11: no x11 channel %d", id); | |
2240 | for (i = 0; s->x11_chanids[i] != -1; i++) { | |
2241 | debug("session_close_single_x11: session %d: " | |
2242 | "closing channel %d", s->self, s->x11_chanids[i]); | |
2243 | /* | |
2244 | * The channel "id" is already closing, but make sure we | |
2245 | * close all of its siblings. | |
2246 | */ | |
2247 | if (s->x11_chanids[i] != id) | |
2248 | session_close_x11(s->x11_chanids[i]); | |
2249 | } | |
2250 | xfree(s->x11_chanids); | |
2251 | s->x11_chanids = NULL; | |
2252 | if (s->display) { | |
2253 | xfree(s->display); | |
2254 | s->display = NULL; | |
2255 | } | |
2256 | if (s->auth_proto) { | |
2257 | xfree(s->auth_proto); | |
2258 | s->auth_proto = NULL; | |
2259 | } | |
2260 | if (s->auth_data) { | |
2261 | xfree(s->auth_data); | |
2262 | s->auth_data = NULL; | |
2263 | } | |
2264 | if (s->auth_display) { | |
2265 | xfree(s->auth_display); | |
2266 | s->auth_display = NULL; | |
2267 | } | |
2268 | } | |
2269 | ||
2270 | static void | |
2271 | session_exit_message(Session *s, int status) | |
2272 | { | |
2273 | Channel *c; | |
2274 | ||
2275 | if ((c = channel_lookup(s->chanid)) == NULL) | |
2276 | fatal("session_exit_message: session %d: no channel %d", | |
2277 | s->self, s->chanid); | |
2278 | debug("session_exit_message: session %d channel %d pid %ld", | |
2279 | s->self, s->chanid, (long)s->pid); | |
2280 | ||
2281 | if (WIFEXITED(status)) { | |
2282 | channel_request_start(s->chanid, "exit-status", 0); | |
2283 | packet_put_int(WEXITSTATUS(status)); | |
2284 | packet_send(); | |
2285 | } else if (WIFSIGNALED(status)) { | |
2286 | channel_request_start(s->chanid, "exit-signal", 0); | |
2287 | packet_put_cstring(sig2name(WTERMSIG(status))); | |
2288 | #ifdef WCOREDUMP | |
2289 | packet_put_char(WCOREDUMP(status)? 1 : 0); | |
2290 | #else /* WCOREDUMP */ | |
2291 | packet_put_char(0); | |
2292 | #endif /* WCOREDUMP */ | |
2293 | packet_put_cstring(""); | |
2294 | packet_put_cstring(""); | |
2295 | packet_send(); | |
2296 | } else { | |
2297 | /* Some weird exit cause. Just exit. */ | |
2298 | packet_disconnect("wait returned status %04x.", status); | |
2299 | } | |
2300 | ||
2301 | /* disconnect channel */ | |
2302 | debug("session_exit_message: release channel %d", s->chanid); | |
2303 | ||
2304 | /* | |
2305 | * Adjust cleanup callback attachment to send close messages when | |
2306 | * the channel gets EOF. The session will be then be closed | |
2307 | * by session_close_by_channel when the childs close their fds. | |
2308 | */ | |
2309 | channel_register_cleanup(c->self, session_close_by_channel, 1); | |
2310 | ||
2311 | /* | |
2312 | * emulate a write failure with 'chan_write_failed', nobody will be | |
2313 | * interested in data we write. | |
2314 | * Note that we must not call 'chan_read_failed', since there could | |
2315 | * be some more data waiting in the pipe. | |
2316 | */ | |
2317 | if (c->ostate != CHAN_OUTPUT_CLOSED) | |
2318 | chan_write_failed(c); | |
2319 | } | |
2320 | ||
2321 | void | |
2322 | session_close(Session *s) | |
2323 | { | |
2324 | u_int i; | |
2325 | ||
2326 | debug("session_close: session %d pid %ld", s->self, (long)s->pid); | |
2327 | if (s->ttyfd != -1) | |
2328 | session_pty_cleanup(s); | |
2329 | if (s->term) | |
2330 | xfree(s->term); | |
2331 | if (s->display) | |
2332 | xfree(s->display); | |
2333 | if (s->x11_chanids) | |
2334 | xfree(s->x11_chanids); | |
2335 | if (s->auth_display) | |
2336 | xfree(s->auth_display); | |
2337 | if (s->auth_data) | |
2338 | xfree(s->auth_data); | |
2339 | if (s->auth_proto) | |
2340 | xfree(s->auth_proto); | |
2341 | s->used = 0; | |
2342 | if (s->env != NULL) { | |
2343 | for (i = 0; i < s->num_env; i++) { | |
2344 | xfree(s->env[i].name); | |
2345 | xfree(s->env[i].val); | |
2346 | } | |
2347 | xfree(s->env); | |
2348 | } | |
2349 | session_proctitle(s); | |
2350 | } | |
2351 | ||
2352 | void | |
2353 | session_close_by_pid(pid_t pid, int status) | |
2354 | { | |
2355 | Session *s = session_by_pid(pid); | |
2356 | if (s == NULL) { | |
2357 | debug("session_close_by_pid: no session for pid %ld", | |
2358 | (long)pid); | |
2359 | return; | |
2360 | } | |
2361 | if (s->chanid != -1) | |
2362 | session_exit_message(s, status); | |
2363 | if (s->ttyfd != -1) | |
2364 | session_pty_cleanup(s); | |
2365 | s->pid = 0; | |
2366 | } | |
2367 | ||
2368 | /* | |
2369 | * this is called when a channel dies before | |
2370 | * the session 'child' itself dies | |
2371 | */ | |
2372 | void | |
2373 | session_close_by_channel(int id, void *arg) | |
2374 | { | |
2375 | Session *s = session_by_channel(id); | |
2376 | u_int i; | |
2377 | ||
2378 | if (s == NULL) { | |
2379 | debug("session_close_by_channel: no session for id %d", id); | |
2380 | return; | |
2381 | } | |
2382 | debug("session_close_by_channel: channel %d child %ld", | |
2383 | id, (long)s->pid); | |
2384 | if (s->pid != 0) { | |
2385 | debug("session_close_by_channel: channel %d: has child", id); | |
2386 | /* | |
2387 | * delay detach of session, but release pty, since | |
2388 | * the fd's to the child are already closed | |
2389 | */ | |
2390 | if (s->ttyfd != -1) | |
2391 | session_pty_cleanup(s); | |
2392 | return; | |
2393 | } | |
2394 | /* detach by removing callback */ | |
2395 | channel_cancel_cleanup(s->chanid); | |
2396 | ||
2397 | /* Close any X11 listeners associated with this session */ | |
2398 | if (s->x11_chanids != NULL) { | |
2399 | for (i = 0; s->x11_chanids[i] != -1; i++) { | |
2400 | session_close_x11(s->x11_chanids[i]); | |
2401 | s->x11_chanids[i] = -1; | |
2402 | } | |
2403 | } | |
2404 | ||
2405 | s->chanid = -1; | |
2406 | session_close(s); | |
2407 | } | |
2408 | ||
2409 | void | |
2410 | session_destroy_all(void (*closefunc)(Session *)) | |
2411 | { | |
2412 | int i; | |
2413 | for (i = 0; i < MAX_SESSIONS; i++) { | |
2414 | Session *s = &sessions[i]; | |
2415 | if (s->used) { | |
2416 | if (closefunc != NULL) | |
2417 | closefunc(s); | |
2418 | else | |
2419 | session_close(s); | |
2420 | } | |
2421 | } | |
2422 | } | |
2423 | ||
2424 | static char * | |
2425 | session_tty_list(void) | |
2426 | { | |
2427 | static char buf[1024]; | |
2428 | int i; | |
2429 | char *cp; | |
2430 | ||
2431 | buf[0] = '\0'; | |
2432 | for (i = 0; i < MAX_SESSIONS; i++) { | |
2433 | Session *s = &sessions[i]; | |
2434 | if (s->used && s->ttyfd != -1) { | |
2435 | ||
2436 | if (strncmp(s->tty, "/dev/", 5) != 0) { | |
2437 | cp = strrchr(s->tty, '/'); | |
2438 | cp = (cp == NULL) ? s->tty : cp + 1; | |
2439 | } else | |
2440 | cp = s->tty + 5; | |
2441 | ||
2442 | if (buf[0] != '\0') | |
2443 | strlcat(buf, ",", sizeof buf); | |
2444 | strlcat(buf, cp, sizeof buf); | |
2445 | } | |
2446 | } | |
2447 | if (buf[0] == '\0') | |
2448 | strlcpy(buf, "notty", sizeof buf); | |
2449 | return buf; | |
2450 | } | |
2451 | ||
2452 | void | |
2453 | session_proctitle(Session *s) | |
2454 | { | |
2455 | if (s->pw == NULL) | |
2456 | error("no user for session %d", s->self); | |
2457 | else | |
2458 | setproctitle("%s@%s", s->pw->pw_name, session_tty_list()); | |
2459 | } | |
2460 | ||
2461 | int | |
2462 | session_setup_x11fwd(Session *s) | |
2463 | { | |
2464 | struct stat st; | |
2465 | char display[512], auth_display[512]; | |
2466 | char hostname[MAXHOSTNAMELEN]; | |
2467 | u_int i; | |
2468 | ||
2469 | if (no_x11_forwarding_flag) { | |
2470 | packet_send_debug("X11 forwarding disabled in user configuration file."); | |
2471 | return 0; | |
2472 | } | |
2473 | if (!options.x11_forwarding) { | |
2474 | debug("X11 forwarding disabled in server configuration file."); | |
2475 | return 0; | |
2476 | } | |
2477 | if (!options.xauth_location || | |
2478 | (stat(options.xauth_location, &st) == -1)) { | |
2479 | packet_send_debug("No xauth program; cannot forward with spoofing."); | |
2480 | return 0; | |
2481 | } | |
2482 | if (options.use_login) { | |
2483 | packet_send_debug("X11 forwarding disabled; " | |
2484 | "not compatible with UseLogin=yes."); | |
2485 | return 0; | |
2486 | } | |
2487 | if (s->display != NULL) { | |
2488 | debug("X11 display already set."); | |
2489 | return 0; | |
2490 | } | |
2491 | if (x11_create_display_inet(options.x11_display_offset, | |
2492 | options.x11_use_localhost, s->single_connection, | |
2493 | &s->display_number, &s->x11_chanids) == -1) { | |
2494 | debug("x11_create_display_inet failed."); | |
2495 | return 0; | |
2496 | } | |
2497 | for (i = 0; s->x11_chanids[i] != -1; i++) { | |
2498 | channel_register_cleanup(s->x11_chanids[i], | |
2499 | session_close_single_x11, 0); | |
2500 | } | |
2501 | ||
2502 | /* Set up a suitable value for the DISPLAY variable. */ | |
2503 | if (gethostname(hostname, sizeof(hostname)) < 0) | |
2504 | fatal("gethostname: %.100s", strerror(errno)); | |
2505 | /* | |
2506 | * auth_display must be used as the displayname when the | |
2507 | * authorization entry is added with xauth(1). This will be | |
2508 | * different than the DISPLAY string for localhost displays. | |
2509 | */ | |
2510 | if (options.x11_use_localhost) { | |
2511 | snprintf(display, sizeof display, "localhost:%u.%u", | |
2512 | s->display_number, s->screen); | |
2513 | snprintf(auth_display, sizeof auth_display, "unix:%u.%u", | |
2514 | s->display_number, s->screen); | |
2515 | s->display = xstrdup(display); | |
2516 | s->auth_display = xstrdup(auth_display); | |
2517 | } else { | |
2518 | #ifdef IPADDR_IN_DISPLAY | |
2519 | struct hostent *he; | |
2520 | struct in_addr my_addr; | |
2521 | ||
2522 | he = gethostbyname(hostname); | |
2523 | if (he == NULL) { | |
2524 | error("Can't get IP address for X11 DISPLAY."); | |
2525 | packet_send_debug("Can't get IP address for X11 DISPLAY."); | |
2526 | return 0; | |
2527 | } | |
2528 | memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr)); | |
2529 | snprintf(display, sizeof display, "%.50s:%u.%u", inet_ntoa(my_addr), | |
2530 | s->display_number, s->screen); | |
2531 | #else | |
2532 | snprintf(display, sizeof display, "%.400s:%u.%u", hostname, | |
2533 | s->display_number, s->screen); | |
2534 | #endif | |
2535 | s->display = xstrdup(display); | |
2536 | s->auth_display = xstrdup(display); | |
2537 | } | |
2538 | ||
2539 | return 1; | |
2540 | } | |
2541 | ||
2542 | static void | |
2543 | do_authenticated2(Authctxt *authctxt) | |
2544 | { | |
2545 | server_loop2(authctxt); | |
2546 | } | |
2547 | ||
2548 | void | |
2549 | do_cleanup(Authctxt *authctxt) | |
2550 | { | |
2551 | static int called = 0; | |
2552 | ||
2553 | debug("do_cleanup"); | |
2554 | ||
2555 | /* no cleanup if we're in the child for login shell */ | |
2556 | if (is_child) | |
2557 | return; | |
2558 | ||
2559 | /* avoid double cleanup */ | |
2560 | if (called) | |
2561 | return; | |
2562 | called = 1; | |
2563 | ||
2564 | if (authctxt == NULL) | |
2565 | return; | |
2566 | ||
2567 | #ifdef USE_PAM | |
2568 | if (options.use_pam) { | |
2569 | sshpam_cleanup(); | |
2570 | sshpam_thread_cleanup(); | |
2571 | } | |
2572 | #endif | |
2573 | ||
2574 | if (!authctxt->authenticated) | |
2575 | return; | |
2576 | ||
2577 | #ifdef KRB5 | |
2578 | if (options.kerberos_ticket_cleanup && | |
2579 | authctxt->krb5_ctx) | |
2580 | krb5_cleanup_proc(authctxt); | |
2581 | #endif | |
2582 | ||
2583 | #ifdef GSSAPI | |
2584 | if (compat20 && options.gss_cleanup_creds) | |
2585 | ssh_gssapi_cleanup_creds(); | |
2586 | #endif | |
2587 | ||
2588 | /* remove agent socket */ | |
2589 | auth_sock_cleanup_proc(authctxt->pw); | |
2590 | ||
2591 | /* | |
2592 | * Cleanup ptys/utmp only if privsep is disabled, | |
2593 | * or if running in monitor. | |
2594 | */ | |
2595 | if (!use_privsep || mm_is_monitor()) | |
2596 | session_destroy_all(session_pty_cleanup2); | |
2597 | } |