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3c0ef626 | 1 | /* |
2 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland | |
3 | * All rights reserved | |
4 | * | |
5 | * As far as I am concerned, the code I have written for this software | |
6 | * can be used freely for any purpose. Any derived versions of this | |
7 | * software must be clearly marked as such, and if the derived work is | |
8 | * incompatible with the protocol description in the RFC file, it must be | |
9 | * called by a name other than "ssh" or "Secure Shell". | |
10 | * | |
11 | * SSH2 support by Markus Friedl. | |
12 | * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved. | |
13 | * | |
14 | * Redistribution and use in source and binary forms, with or without | |
15 | * modification, are permitted provided that the following conditions | |
16 | * are met: | |
17 | * 1. Redistributions of source code must retain the above copyright | |
18 | * notice, this list of conditions and the following disclaimer. | |
19 | * 2. Redistributions in binary form must reproduce the above copyright | |
20 | * notice, this list of conditions and the following disclaimer in the | |
21 | * documentation and/or other materials provided with the distribution. | |
22 | * | |
23 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR | |
24 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES | |
25 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. | |
26 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, | |
27 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | |
28 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | |
29 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | |
30 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
31 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | |
32 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
33 | */ | |
34 | ||
35 | #include "includes.h" | |
2ce0bfe4 | 36 | RCSID("$OpenBSD: session.c,v 1.186 2005/07/25 11:59:40 markus Exp $"); |
3c0ef626 | 37 | |
38 | #include "ssh.h" | |
39 | #include "ssh1.h" | |
40 | #include "ssh2.h" | |
41 | #include "xmalloc.h" | |
42 | #include "sshpty.h" | |
43 | #include "packet.h" | |
44 | #include "buffer.h" | |
7e82606e | 45 | #include "match.h" |
3c0ef626 | 46 | #include "uidswap.h" |
47 | #include "compat.h" | |
48 | #include "channels.h" | |
49 | #include "bufaux.h" | |
50 | #include "auth.h" | |
51 | #include "auth-options.h" | |
52 | #include "pathnames.h" | |
53 | #include "log.h" | |
54 | #include "servconf.h" | |
55 | #include "sshlogin.h" | |
56 | #include "serverloop.h" | |
57 | #include "canohost.h" | |
58 | #include "session.h" | |
2ce0bfe4 | 59 | #include "kex.h" |
350391c5 | 60 | #include "monitor_wrap.h" |
3c0ef626 | 61 | |
540d72c3 | 62 | #if defined(KRB5) && defined(USE_AFS) |
63 | #include <kafs.h> | |
64 | #endif | |
65 | ||
5598e598 | 66 | #ifdef GSSAPI |
67 | #include "ssh-gss.h" | |
68 | #endif | |
69 | ||
3c0ef626 | 70 | /* func */ |
71 | ||
72 | Session *session_new(void); | |
73 | void session_set_fds(Session *, int, int, int); | |
540d72c3 | 74 | void session_pty_cleanup(Session *); |
3c0ef626 | 75 | void session_proctitle(Session *); |
76 | int session_setup_x11fwd(Session *); | |
77 | void do_exec_pty(Session *, const char *); | |
78 | void do_exec_no_pty(Session *, const char *); | |
79 | void do_exec(Session *, const char *); | |
80 | void do_login(Session *, const char *); | |
81 | #ifdef LOGIN_NEEDS_UTMPX | |
82 | static void do_pre_login(Session *s); | |
83 | #endif | |
84 | void do_child(Session *, const char *); | |
85 | void do_motd(void); | |
86 | int check_quietlogin(Session *, const char *); | |
87 | ||
88 | static void do_authenticated1(Authctxt *); | |
89 | static void do_authenticated2(Authctxt *); | |
90 | ||
3c0ef626 | 91 | static int session_pty_req(Session *); |
92 | ||
75be3237 | 93 | #ifdef SESSION_HOOKS |
94 | static void execute_session_hook(char* prog, Authctxt *authctxt, | |
95 | int startup, int save); | |
96 | #endif | |
97 | ||
3c0ef626 | 98 | /* import */ |
99 | extern ServerOptions options; | |
100 | extern char *__progname; | |
101 | extern int log_stderr; | |
102 | extern int debug_flag; | |
103 | extern u_int utmp_len; | |
104 | extern int startup_pipe; | |
105 | extern void destroy_sensitive_data(void); | |
7cac2b65 | 106 | extern Buffer loginmsg; |
3c0ef626 | 107 | |
108 | /* original command from peer. */ | |
109 | const char *original_command = NULL; | |
110 | ||
111 | /* data */ | |
112 | #define MAX_SESSIONS 10 | |
113 | Session sessions[MAX_SESSIONS]; | |
114 | ||
3c0ef626 | 115 | #ifdef HAVE_LOGIN_CAP |
350391c5 | 116 | login_cap_t *lc; |
3c0ef626 | 117 | #endif |
118 | ||
540d72c3 | 119 | static int is_child = 0; |
120 | ||
44a053a3 | 121 | /* Name and directory of socket for authentication agent forwarding. */ |
122 | static char *auth_sock_name = NULL; | |
123 | static char *auth_sock_dir = NULL; | |
124 | ||
125 | /* removes the agent forwarding socket */ | |
126 | ||
127 | static void | |
540d72c3 | 128 | auth_sock_cleanup_proc(struct passwd *pw) |
44a053a3 | 129 | { |
44a053a3 | 130 | if (auth_sock_name != NULL) { |
131 | temporarily_use_uid(pw); | |
132 | unlink(auth_sock_name); | |
133 | rmdir(auth_sock_dir); | |
134 | auth_sock_name = NULL; | |
135 | restore_uid(); | |
136 | } | |
137 | } | |
138 | ||
139 | static int | |
140 | auth_input_request_forwarding(struct passwd * pw) | |
141 | { | |
142 | Channel *nc; | |
143 | int sock; | |
144 | struct sockaddr_un sunaddr; | |
145 | ||
146 | if (auth_sock_name != NULL) { | |
147 | error("authentication forwarding requested twice."); | |
148 | return 0; | |
149 | } | |
150 | ||
151 | /* Temporarily drop privileged uid for mkdir/bind. */ | |
152 | temporarily_use_uid(pw); | |
153 | ||
154 | /* Allocate a buffer for the socket name, and format the name. */ | |
155 | auth_sock_name = xmalloc(MAXPATHLEN); | |
156 | auth_sock_dir = xmalloc(MAXPATHLEN); | |
540d72c3 | 157 | strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN); |
44a053a3 | 158 | |
159 | /* Create private directory for socket */ | |
160 | if (mkdtemp(auth_sock_dir) == NULL) { | |
161 | packet_send_debug("Agent forwarding disabled: " | |
162 | "mkdtemp() failed: %.100s", strerror(errno)); | |
163 | restore_uid(); | |
164 | xfree(auth_sock_name); | |
165 | xfree(auth_sock_dir); | |
166 | auth_sock_name = NULL; | |
167 | auth_sock_dir = NULL; | |
168 | return 0; | |
169 | } | |
170 | snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%ld", | |
171 | auth_sock_dir, (long) getpid()); | |
172 | ||
44a053a3 | 173 | /* Create the socket. */ |
174 | sock = socket(AF_UNIX, SOCK_STREAM, 0); | |
175 | if (sock < 0) | |
176 | packet_disconnect("socket: %.100s", strerror(errno)); | |
177 | ||
178 | /* Bind it to the name. */ | |
179 | memset(&sunaddr, 0, sizeof(sunaddr)); | |
180 | sunaddr.sun_family = AF_UNIX; | |
181 | strlcpy(sunaddr.sun_path, auth_sock_name, sizeof(sunaddr.sun_path)); | |
182 | ||
183 | if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) | |
184 | packet_disconnect("bind: %.100s", strerror(errno)); | |
185 | ||
186 | /* Restore the privileged uid. */ | |
187 | restore_uid(); | |
188 | ||
189 | /* Start listening on the socket. */ | |
540d72c3 | 190 | if (listen(sock, SSH_LISTEN_BACKLOG) < 0) |
44a053a3 | 191 | packet_disconnect("listen: %.100s", strerror(errno)); |
192 | ||
193 | /* Allocate a channel for the authentication agent socket. */ | |
194 | nc = channel_new("auth socket", | |
195 | SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1, | |
196 | CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, | |
7cac2b65 | 197 | 0, "auth socket", 1); |
44a053a3 | 198 | strlcpy(nc->path, auth_sock_name, sizeof(nc->path)); |
199 | return 1; | |
200 | } | |
201 | ||
540d72c3 | 202 | static void |
203 | display_loginmsg(void) | |
204 | { | |
2ce0bfe4 | 205 | if (buffer_len(&loginmsg) > 0) { |
206 | buffer_append(&loginmsg, "\0", 1); | |
207 | printf("%s", (char *)buffer_ptr(&loginmsg)); | |
208 | buffer_clear(&loginmsg); | |
209 | } | |
540d72c3 | 210 | } |
44a053a3 | 211 | |
3c0ef626 | 212 | void |
213 | do_authenticated(Authctxt *authctxt) | |
214 | { | |
bfe49944 | 215 | setproctitle("%s", authctxt->pw->pw_name); |
216 | ||
3c0ef626 | 217 | /* |
218 | * Cancel the alarm we set to limit the time taken for | |
219 | * authentication. | |
220 | */ | |
221 | alarm(0); | |
222 | if (startup_pipe != -1) { | |
223 | close(startup_pipe); | |
224 | startup_pipe = -1; | |
225 | } | |
3c0ef626 | 226 | /* setup the channel layer */ |
227 | if (!no_port_forwarding_flag && options.allow_tcp_forwarding) | |
228 | channel_permit_all_opens(); | |
229 | ||
230 | if (compat20) | |
231 | do_authenticated2(authctxt); | |
232 | else | |
233 | do_authenticated1(authctxt); | |
234 | ||
75be3237 | 235 | #ifdef SESSION_HOOKS |
236 | if (options.session_hooks_allow && | |
237 | options.session_hooks_shutdown_cmd) | |
238 | { | |
239 | execute_session_hook(options.session_hooks_shutdown_cmd, | |
240 | authctxt, | |
241 | /* startup = */ 0, /* save = */ 0); | |
242 | ||
243 | if (authctxt->session_env_file) | |
244 | { | |
245 | free(authctxt->session_env_file); | |
246 | } | |
247 | } | |
248 | #endif | |
540d72c3 | 249 | |
250 | do_cleanup(authctxt); | |
3c0ef626 | 251 | } |
252 | ||
253 | /* | |
254 | * Prepares for an interactive session. This is called after the user has | |
255 | * been successfully authenticated. During this message exchange, pseudo | |
256 | * terminals are allocated, X11, TCP/IP, and authentication agent forwardings | |
257 | * are requested, etc. | |
258 | */ | |
259 | static void | |
260 | do_authenticated1(Authctxt *authctxt) | |
261 | { | |
262 | Session *s; | |
263 | char *command; | |
e9702f7d | 264 | int success, type, screen_flag; |
276b07a3 | 265 | int enable_compression_after_reply = 0; |
266 | u_int proto_len, data_len, dlen, compression_level = 0; | |
3c0ef626 | 267 | |
268 | s = session_new(); | |
dfddba3d | 269 | if (s == NULL) { |
270 | error("no more sessions"); | |
271 | return; | |
272 | } | |
3c0ef626 | 273 | s->authctxt = authctxt; |
274 | s->pw = authctxt->pw; | |
275 | ||
276 | /* | |
277 | * We stay in this loop until the client requests to execute a shell | |
278 | * or a command. | |
279 | */ | |
280 | for (;;) { | |
281 | success = 0; | |
282 | ||
283 | /* Get a packet from the client. */ | |
e9702f7d | 284 | type = packet_read(); |
3c0ef626 | 285 | |
286 | /* Process the packet. */ | |
287 | switch (type) { | |
288 | case SSH_CMSG_REQUEST_COMPRESSION: | |
3c0ef626 | 289 | compression_level = packet_get_int(); |
e9702f7d | 290 | packet_check_eom(); |
3c0ef626 | 291 | if (compression_level < 1 || compression_level > 9) { |
7e82606e | 292 | packet_send_debug("Received invalid compression level %d.", |
e9702f7d | 293 | compression_level); |
3c0ef626 | 294 | break; |
295 | } | |
2ce0bfe4 | 296 | if (options.compression == COMP_NONE) { |
44a053a3 | 297 | debug2("compression disabled"); |
298 | break; | |
299 | } | |
3c0ef626 | 300 | /* Enable compression after we have responded with SUCCESS. */ |
301 | enable_compression_after_reply = 1; | |
302 | success = 1; | |
303 | break; | |
304 | ||
305 | case SSH_CMSG_REQUEST_PTY: | |
306 | success = session_pty_req(s); | |
307 | break; | |
308 | ||
309 | case SSH_CMSG_X11_REQUEST_FORWARDING: | |
310 | s->auth_proto = packet_get_string(&proto_len); | |
311 | s->auth_data = packet_get_string(&data_len); | |
312 | ||
313 | screen_flag = packet_get_protocol_flags() & | |
314 | SSH_PROTOFLAG_SCREEN_NUMBER; | |
315 | debug2("SSH_PROTOFLAG_SCREEN_NUMBER: %d", screen_flag); | |
316 | ||
317 | if (packet_remaining() == 4) { | |
318 | if (!screen_flag) | |
319 | debug2("Buggy client: " | |
320 | "X11 screen flag missing"); | |
321 | s->screen = packet_get_int(); | |
322 | } else { | |
323 | s->screen = 0; | |
324 | } | |
e9702f7d | 325 | packet_check_eom(); |
3c0ef626 | 326 | success = session_setup_x11fwd(s); |
327 | if (!success) { | |
328 | xfree(s->auth_proto); | |
329 | xfree(s->auth_data); | |
330 | s->auth_proto = NULL; | |
331 | s->auth_data = NULL; | |
332 | } | |
333 | break; | |
334 | ||
335 | case SSH_CMSG_AGENT_REQUEST_FORWARDING: | |
336 | if (no_agent_forwarding_flag || compat13) { | |
337 | debug("Authentication agent forwarding not permitted for this authentication."); | |
338 | break; | |
339 | } | |
340 | debug("Received authentication agent forwarding request."); | |
341 | success = auth_input_request_forwarding(s->pw); | |
342 | break; | |
343 | ||
344 | case SSH_CMSG_PORT_FORWARD_REQUEST: | |
345 | if (no_port_forwarding_flag) { | |
346 | debug("Port forwarding not permitted for this authentication."); | |
347 | break; | |
348 | } | |
349 | if (!options.allow_tcp_forwarding) { | |
350 | debug("Port forwarding not permitted."); | |
351 | break; | |
352 | } | |
353 | debug("Received TCP/IP port forwarding request."); | |
354 | channel_input_port_forward_request(s->pw->pw_uid == 0, options.gateway_ports); | |
355 | success = 1; | |
356 | break; | |
357 | ||
358 | case SSH_CMSG_MAX_PACKET_SIZE: | |
359 | if (packet_set_maxsize(packet_get_int()) > 0) | |
360 | success = 1; | |
361 | break; | |
e9702f7d | 362 | |
3c0ef626 | 363 | case SSH_CMSG_EXEC_SHELL: |
364 | case SSH_CMSG_EXEC_CMD: | |
365 | if (type == SSH_CMSG_EXEC_CMD) { | |
366 | command = packet_get_string(&dlen); | |
367 | debug("Exec command '%.500s'", command); | |
368 | do_exec(s, command); | |
369 | xfree(command); | |
370 | } else { | |
371 | do_exec(s, NULL); | |
372 | } | |
e9702f7d | 373 | packet_check_eom(); |
3c0ef626 | 374 | session_close(s); |
375 | return; | |
376 | ||
377 | default: | |
378 | /* | |
379 | * Any unknown messages in this phase are ignored, | |
380 | * and a failure message is returned. | |
381 | */ | |
7cac2b65 | 382 | logit("Unknown packet type received after authentication: %d", type); |
3c0ef626 | 383 | } |
384 | packet_start(success ? SSH_SMSG_SUCCESS : SSH_SMSG_FAILURE); | |
385 | packet_send(); | |
386 | packet_write_wait(); | |
387 | ||
388 | /* Enable compression now that we have replied if appropriate. */ | |
389 | if (enable_compression_after_reply) { | |
390 | enable_compression_after_reply = 0; | |
391 | packet_start_compression(compression_level); | |
392 | } | |
393 | } | |
394 | } | |
395 | ||
396 | /* | |
397 | * This is called to fork and execute a command when we have no tty. This | |
398 | * will call do_child from the child, and server_loop from the parent after | |
399 | * setting up file descriptors and such. | |
400 | */ | |
401 | void | |
402 | do_exec_no_pty(Session *s, const char *command) | |
403 | { | |
44a053a3 | 404 | pid_t pid; |
3c0ef626 | 405 | |
406 | #ifdef USE_PIPES | |
407 | int pin[2], pout[2], perr[2]; | |
408 | /* Allocate pipes for communicating with the program. */ | |
409 | if (pipe(pin) < 0 || pipe(pout) < 0 || pipe(perr) < 0) | |
410 | packet_disconnect("Could not create pipes: %.100s", | |
411 | strerror(errno)); | |
412 | #else /* USE_PIPES */ | |
413 | int inout[2], err[2]; | |
414 | /* Uses socket pairs to communicate with the program. */ | |
415 | if (socketpair(AF_UNIX, SOCK_STREAM, 0, inout) < 0 || | |
416 | socketpair(AF_UNIX, SOCK_STREAM, 0, err) < 0) | |
417 | packet_disconnect("Could not create socket pairs: %.100s", | |
418 | strerror(errno)); | |
419 | #endif /* USE_PIPES */ | |
420 | if (s == NULL) | |
421 | fatal("do_exec_no_pty: no session"); | |
422 | ||
423 | session_proctitle(s); | |
424 | ||
425 | #if defined(USE_PAM) | |
540d72c3 | 426 | if (options.use_pam && !use_privsep) |
7cac2b65 | 427 | do_pam_setcred(1); |
3c0ef626 | 428 | #endif /* USE_PAM */ |
429 | ||
430 | /* Fork the child. */ | |
431 | if ((pid = fork()) == 0) { | |
540d72c3 | 432 | is_child = 1; |
d03f4262 | 433 | |
3c0ef626 | 434 | /* Child. Reinitialize the log since the pid has changed. */ |
435 | log_init(__progname, options.log_level, options.log_facility, log_stderr); | |
436 | ||
437 | /* | |
438 | * Create a new session and process group since the 4.4BSD | |
439 | * setlogin() affects the entire process group. | |
440 | */ | |
441 | if (setsid() < 0) | |
442 | error("setsid failed: %.100s", strerror(errno)); | |
443 | ||
444 | #ifdef USE_PIPES | |
445 | /* | |
446 | * Redirect stdin. We close the parent side of the socket | |
447 | * pair, and make the child side the standard input. | |
448 | */ | |
449 | close(pin[1]); | |
450 | if (dup2(pin[0], 0) < 0) | |
451 | perror("dup2 stdin"); | |
452 | close(pin[0]); | |
453 | ||
454 | /* Redirect stdout. */ | |
455 | close(pout[0]); | |
456 | if (dup2(pout[1], 1) < 0) | |
457 | perror("dup2 stdout"); | |
458 | close(pout[1]); | |
459 | ||
460 | /* Redirect stderr. */ | |
461 | close(perr[0]); | |
462 | if (dup2(perr[1], 2) < 0) | |
463 | perror("dup2 stderr"); | |
464 | close(perr[1]); | |
465 | #else /* USE_PIPES */ | |
466 | /* | |
467 | * Redirect stdin, stdout, and stderr. Stdin and stdout will | |
468 | * use the same socket, as some programs (particularly rdist) | |
469 | * seem to depend on it. | |
470 | */ | |
471 | close(inout[1]); | |
472 | close(err[1]); | |
473 | if (dup2(inout[0], 0) < 0) /* stdin */ | |
474 | perror("dup2 stdin"); | |
475 | if (dup2(inout[0], 1) < 0) /* stdout. Note: same socket as stdin. */ | |
476 | perror("dup2 stdout"); | |
477 | if (dup2(err[0], 2) < 0) /* stderr */ | |
478 | perror("dup2 stderr"); | |
479 | #endif /* USE_PIPES */ | |
480 | ||
d03f4262 | 481 | #ifdef _UNICOS |
482 | cray_init_job(s->pw); /* set up cray jid and tmpdir */ | |
483 | #endif | |
484 | ||
3c0ef626 | 485 | /* Do processing for the child (exec command etc). */ |
486 | do_child(s, command); | |
487 | /* NOTREACHED */ | |
488 | } | |
d03f4262 | 489 | #ifdef _UNICOS |
490 | signal(WJSIGNAL, cray_job_termination_handler); | |
491 | #endif /* _UNICOS */ | |
3c0ef626 | 492 | #ifdef HAVE_CYGWIN |
493 | if (is_winnt) | |
494 | cygwin_set_impersonation_token(INVALID_HANDLE_VALUE); | |
495 | #endif | |
496 | if (pid < 0) | |
497 | packet_disconnect("fork failed: %.100s", strerror(errno)); | |
498 | s->pid = pid; | |
499 | /* Set interactive/non-interactive mode. */ | |
500 | packet_set_interactive(s->display != NULL); | |
501 | #ifdef USE_PIPES | |
502 | /* We are the parent. Close the child sides of the pipes. */ | |
503 | close(pin[0]); | |
504 | close(pout[1]); | |
505 | close(perr[1]); | |
506 | ||
507 | if (compat20) { | |
7e82606e | 508 | if (s->is_subsystem) { |
509 | close(perr[0]); | |
510 | perr[0] = -1; | |
511 | } | |
512 | session_set_fds(s, pin[1], pout[0], perr[0]); | |
3c0ef626 | 513 | } else { |
514 | /* Enter the interactive session. */ | |
515 | server_loop(pid, pin[1], pout[0], perr[0]); | |
516 | /* server_loop has closed pin[1], pout[0], and perr[0]. */ | |
517 | } | |
518 | #else /* USE_PIPES */ | |
519 | /* We are the parent. Close the child sides of the socket pairs. */ | |
520 | close(inout[0]); | |
521 | close(err[0]); | |
522 | ||
12a403af | 523 | /* |
524 | * Clear loginmsg, since it's the child's responsibility to display | |
525 | * it to the user, otherwise multiple sessions may accumulate | |
526 | * multiple copies of the login messages. | |
527 | */ | |
528 | buffer_clear(&loginmsg); | |
529 | ||
3c0ef626 | 530 | /* |
531 | * Enter the interactive session. Note: server_loop must be able to | |
532 | * handle the case that fdin and fdout are the same. | |
533 | */ | |
534 | if (compat20) { | |
535 | session_set_fds(s, inout[1], inout[1], s->is_subsystem ? -1 : err[1]); | |
536 | } else { | |
537 | server_loop(pid, inout[1], inout[1], err[1]); | |
538 | /* server_loop has closed inout[1] and err[1]. */ | |
539 | } | |
540 | #endif /* USE_PIPES */ | |
541 | } | |
542 | ||
543 | /* | |
544 | * This is called to fork and execute a command when we have a tty. This | |
545 | * will call do_child from the child, and server_loop from the parent after | |
546 | * setting up file descriptors, controlling tty, updating wtmp, utmp, | |
547 | * lastlog, and other such operations. | |
548 | */ | |
549 | void | |
550 | do_exec_pty(Session *s, const char *command) | |
551 | { | |
552 | int fdout, ptyfd, ttyfd, ptymaster; | |
553 | pid_t pid; | |
554 | ||
555 | if (s == NULL) | |
556 | fatal("do_exec_pty: no session"); | |
557 | ptyfd = s->ptyfd; | |
558 | ttyfd = s->ttyfd; | |
559 | ||
560 | #if defined(USE_PAM) | |
7cac2b65 | 561 | if (options.use_pam) { |
562 | do_pam_set_tty(s->tty); | |
540d72c3 | 563 | if (!use_privsep) |
564 | do_pam_setcred(1); | |
7cac2b65 | 565 | } |
3c0ef626 | 566 | #endif |
567 | ||
568 | /* Fork the child. */ | |
569 | if ((pid = fork()) == 0) { | |
540d72c3 | 570 | is_child = 1; |
3c0ef626 | 571 | |
572 | /* Child. Reinitialize the log because the pid has changed. */ | |
573 | log_init(__progname, options.log_level, options.log_facility, log_stderr); | |
574 | /* Close the master side of the pseudo tty. */ | |
575 | close(ptyfd); | |
576 | ||
577 | /* Make the pseudo tty our controlling tty. */ | |
578 | pty_make_controlling_tty(&ttyfd, s->tty); | |
579 | ||
580 | /* Redirect stdin/stdout/stderr from the pseudo tty. */ | |
581 | if (dup2(ttyfd, 0) < 0) | |
582 | error("dup2 stdin: %s", strerror(errno)); | |
583 | if (dup2(ttyfd, 1) < 0) | |
584 | error("dup2 stdout: %s", strerror(errno)); | |
585 | if (dup2(ttyfd, 2) < 0) | |
586 | error("dup2 stderr: %s", strerror(errno)); | |
587 | ||
588 | /* Close the extra descriptor for the pseudo tty. */ | |
589 | close(ttyfd); | |
590 | ||
591 | /* record login, etc. similar to login(1) */ | |
592 | #ifndef HAVE_OSF_SIA | |
d03f4262 | 593 | if (!(options.use_login && command == NULL)) { |
594 | #ifdef _UNICOS | |
595 | cray_init_job(s->pw); /* set up cray jid and tmpdir */ | |
596 | #endif /* _UNICOS */ | |
3c0ef626 | 597 | do_login(s, command); |
d03f4262 | 598 | } |
3c0ef626 | 599 | # ifdef LOGIN_NEEDS_UTMPX |
600 | else | |
601 | do_pre_login(s); | |
602 | # endif | |
603 | #endif | |
604 | ||
605 | /* Do common processing for the child, such as execing the command. */ | |
606 | do_child(s, command); | |
607 | /* NOTREACHED */ | |
608 | } | |
d03f4262 | 609 | #ifdef _UNICOS |
610 | signal(WJSIGNAL, cray_job_termination_handler); | |
611 | #endif /* _UNICOS */ | |
3c0ef626 | 612 | #ifdef HAVE_CYGWIN |
613 | if (is_winnt) | |
614 | cygwin_set_impersonation_token(INVALID_HANDLE_VALUE); | |
615 | #endif | |
616 | if (pid < 0) | |
617 | packet_disconnect("fork failed: %.100s", strerror(errno)); | |
618 | s->pid = pid; | |
619 | ||
620 | /* Parent. Close the slave side of the pseudo tty. */ | |
621 | close(ttyfd); | |
622 | ||
623 | /* | |
624 | * Create another descriptor of the pty master side for use as the | |
625 | * standard input. We could use the original descriptor, but this | |
626 | * simplifies code in server_loop. The descriptor is bidirectional. | |
627 | */ | |
628 | fdout = dup(ptyfd); | |
629 | if (fdout < 0) | |
630 | packet_disconnect("dup #1 failed: %.100s", strerror(errno)); | |
631 | ||
632 | /* we keep a reference to the pty master */ | |
633 | ptymaster = dup(ptyfd); | |
634 | if (ptymaster < 0) | |
635 | packet_disconnect("dup #2 failed: %.100s", strerror(errno)); | |
636 | s->ptymaster = ptymaster; | |
637 | ||
638 | /* Enter interactive session. */ | |
639 | packet_set_interactive(1); | |
640 | if (compat20) { | |
641 | session_set_fds(s, ptyfd, fdout, -1); | |
642 | } else { | |
643 | server_loop(pid, ptyfd, fdout, -1); | |
644 | /* server_loop _has_ closed ptyfd and fdout. */ | |
645 | } | |
646 | } | |
647 | ||
648 | #ifdef LOGIN_NEEDS_UTMPX | |
649 | static void | |
650 | do_pre_login(Session *s) | |
651 | { | |
652 | socklen_t fromlen; | |
653 | struct sockaddr_storage from; | |
654 | pid_t pid = getpid(); | |
655 | ||
656 | /* | |
657 | * Get IP address of client. If the connection is not a socket, let | |
658 | * the address be 0.0.0.0. | |
659 | */ | |
660 | memset(&from, 0, sizeof(from)); | |
d03f4262 | 661 | fromlen = sizeof(from); |
3c0ef626 | 662 | if (packet_connection_is_on_socket()) { |
3c0ef626 | 663 | if (getpeername(packet_get_connection_in(), |
e9702f7d | 664 | (struct sockaddr *) & from, &fromlen) < 0) { |
3c0ef626 | 665 | debug("getpeername: %.100s", strerror(errno)); |
540d72c3 | 666 | cleanup_exit(255); |
3c0ef626 | 667 | } |
668 | } | |
669 | ||
670 | record_utmp_only(pid, s->tty, s->pw->pw_name, | |
7cac2b65 | 671 | get_remote_name_or_ip(utmp_len, options.use_dns), |
bfe49944 | 672 | (struct sockaddr *)&from, fromlen); |
3c0ef626 | 673 | } |
674 | #endif | |
675 | ||
676 | /* | |
677 | * This is called to fork and execute a command. If another command is | |
678 | * to be forced, execute that instead. | |
679 | */ | |
680 | void | |
681 | do_exec(Session *s, const char *command) | |
682 | { | |
683 | if (forced_command) { | |
684 | original_command = command; | |
685 | command = forced_command; | |
686 | debug("Forced command '%.900s'", command); | |
687 | } | |
688 | ||
7cac2b65 | 689 | #if defined(SESSION_HOOKS) |
690 | if (options.session_hooks_allow && | |
691 | (options.session_hooks_startup_cmd || | |
692 | options.session_hooks_shutdown_cmd)) | |
693 | { | |
694 | char env_file[1000]; | |
695 | struct stat st; | |
696 | do | |
697 | { | |
698 | snprintf(env_file, | |
699 | sizeof(env_file), | |
700 | "/tmp/ssh_env_%d%d%d", | |
701 | getuid(), | |
702 | getpid(), | |
703 | rand()); | |
704 | } while (stat(env_file, &st)==0); | |
705 | s->authctxt->session_env_file = strdup(env_file); | |
706 | } | |
707 | #endif | |
708 | ||
709 | #ifdef GSSAPI | |
710 | if (options.gss_authentication) { | |
711 | temporarily_use_uid(s->pw); | |
712 | ssh_gssapi_storecreds(); | |
713 | restore_uid(); | |
714 | } | |
715 | #endif | |
716 | ||
dfddba3d | 717 | #ifdef SSH_AUDIT_EVENTS |
718 | if (command != NULL) | |
719 | PRIVSEP(audit_run_command(command)); | |
720 | else if (s->ttyfd == -1) { | |
721 | char *shell = s->pw->pw_shell; | |
722 | ||
723 | if (shell[0] == '\0') /* empty shell means /bin/sh */ | |
724 | shell =_PATH_BSHELL; | |
725 | PRIVSEP(audit_run_command(shell)); | |
726 | } | |
727 | #endif | |
728 | ||
3c0ef626 | 729 | if (s->ttyfd != -1) |
730 | do_exec_pty(s, command); | |
731 | else | |
732 | do_exec_no_pty(s, command); | |
733 | ||
734 | original_command = NULL; | |
3c0ef626 | 735 | |
7e82606e | 736 | /* |
737 | * Clear loginmsg: it's the child's responsibility to display | |
738 | * it to the user, otherwise multiple sessions may accumulate | |
739 | * multiple copies of the login messages. | |
740 | */ | |
741 | buffer_clear(&loginmsg); | |
742 | } | |
e9702f7d | 743 | |
3c0ef626 | 744 | /* administrative, login(1)-like work */ |
745 | void | |
746 | do_login(Session *s, const char *command) | |
747 | { | |
3c0ef626 | 748 | socklen_t fromlen; |
749 | struct sockaddr_storage from; | |
3c0ef626 | 750 | struct passwd * pw = s->pw; |
751 | pid_t pid = getpid(); | |
752 | ||
753 | /* | |
754 | * Get IP address of client. If the connection is not a socket, let | |
755 | * the address be 0.0.0.0. | |
756 | */ | |
757 | memset(&from, 0, sizeof(from)); | |
bfe49944 | 758 | fromlen = sizeof(from); |
3c0ef626 | 759 | if (packet_connection_is_on_socket()) { |
3c0ef626 | 760 | if (getpeername(packet_get_connection_in(), |
e9702f7d | 761 | (struct sockaddr *) & from, &fromlen) < 0) { |
3c0ef626 | 762 | debug("getpeername: %.100s", strerror(errno)); |
540d72c3 | 763 | cleanup_exit(255); |
3c0ef626 | 764 | } |
765 | } | |
766 | ||
3c0ef626 | 767 | /* Record that there was a login on that tty from the remote host. */ |
350391c5 | 768 | if (!use_privsep) |
769 | record_login(pid, s->tty, pw->pw_name, pw->pw_uid, | |
770 | get_remote_name_or_ip(utmp_len, | |
7cac2b65 | 771 | options.use_dns), |
d03f4262 | 772 | (struct sockaddr *)&from, fromlen); |
3c0ef626 | 773 | |
774 | #ifdef USE_PAM | |
775 | /* | |
776 | * If password change is needed, do it now. | |
777 | * This needs to occur before the ~/.hushlogin check. | |
778 | */ | |
540d72c3 | 779 | if (options.use_pam && !use_privsep && s->authctxt->force_pwchange) { |
780 | display_loginmsg(); | |
3c0ef626 | 781 | do_pam_chauthtok(); |
540d72c3 | 782 | s->authctxt->force_pwchange = 0; |
7cac2b65 | 783 | /* XXX - signal [net] parent to enable forwardings */ |
3c0ef626 | 784 | } |
785 | #endif | |
786 | ||
787 | if (check_quietlogin(s, command)) | |
788 | return; | |
789 | ||
540d72c3 | 790 | display_loginmsg(); |
3c0ef626 | 791 | |
3c0ef626 | 792 | do_motd(); |
793 | } | |
794 | ||
795 | /* | |
796 | * Display the message of the day. | |
797 | */ | |
798 | void | |
799 | do_motd(void) | |
800 | { | |
801 | FILE *f; | |
802 | char buf[256]; | |
803 | ||
804 | if (options.print_motd) { | |
805 | #ifdef HAVE_LOGIN_CAP | |
806 | f = fopen(login_getcapstr(lc, "welcome", "/etc/motd", | |
807 | "/etc/motd"), "r"); | |
808 | #else | |
809 | f = fopen("/etc/motd", "r"); | |
810 | #endif | |
811 | if (f) { | |
812 | while (fgets(buf, sizeof(buf), f)) | |
813 | fputs(buf, stdout); | |
814 | fclose(f); | |
815 | } | |
816 | } | |
817 | } | |
818 | ||
819 | ||
820 | /* | |
821 | * Check for quiet login, either .hushlogin or command given. | |
822 | */ | |
823 | int | |
824 | check_quietlogin(Session *s, const char *command) | |
825 | { | |
826 | char buf[256]; | |
827 | struct passwd *pw = s->pw; | |
828 | struct stat st; | |
829 | ||
830 | /* Return 1 if .hushlogin exists or a command given. */ | |
831 | if (command != NULL) | |
832 | return 1; | |
833 | snprintf(buf, sizeof(buf), "%.200s/.hushlogin", pw->pw_dir); | |
834 | #ifdef HAVE_LOGIN_CAP | |
835 | if (login_getcapbool(lc, "hushlogin", 0) || stat(buf, &st) >= 0) | |
836 | return 1; | |
837 | #else | |
838 | if (stat(buf, &st) >= 0) | |
839 | return 1; | |
840 | #endif | |
841 | return 0; | |
842 | } | |
843 | ||
844 | /* | |
845 | * Sets the value of the given variable in the environment. If the variable | |
846 | * already exists, its value is overriden. | |
847 | */ | |
5598e598 | 848 | void |
3c0ef626 | 849 | child_set_env(char ***envp, u_int *envsizep, const char *name, |
e9702f7d | 850 | const char *value) |
3c0ef626 | 851 | { |
3c0ef626 | 852 | char **env; |
29d88157 | 853 | u_int envsize; |
854 | u_int i, namelen; | |
3c0ef626 | 855 | |
7cac2b65 | 856 | /* |
857 | * If we're passed an uninitialized list, allocate a single null | |
858 | * entry before continuing. | |
859 | */ | |
860 | if (*envp == NULL && *envsizep == 0) { | |
861 | *envp = xmalloc(sizeof(char *)); | |
862 | *envp[0] = NULL; | |
863 | *envsizep = 1; | |
864 | } | |
865 | ||
3c0ef626 | 866 | /* |
867 | * Find the slot where the value should be stored. If the variable | |
868 | * already exists, we reuse the slot; otherwise we append a new slot | |
869 | * at the end of the array, expanding if necessary. | |
870 | */ | |
871 | env = *envp; | |
872 | namelen = strlen(name); | |
873 | for (i = 0; env[i]; i++) | |
874 | if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=') | |
875 | break; | |
876 | if (env[i]) { | |
877 | /* Reuse the slot. */ | |
878 | xfree(env[i]); | |
879 | } else { | |
880 | /* New variable. Expand if necessary. */ | |
29d88157 | 881 | envsize = *envsizep; |
882 | if (i >= envsize - 1) { | |
883 | if (envsize >= 1000) | |
884 | fatal("child_set_env: too many env vars"); | |
885 | envsize += 50; | |
886 | env = (*envp) = xrealloc(env, envsize * sizeof(char *)); | |
887 | *envsizep = envsize; | |
3c0ef626 | 888 | } |
889 | /* Need to set the NULL pointer at end of array beyond the new slot. */ | |
890 | env[i + 1] = NULL; | |
891 | } | |
892 | ||
893 | /* Allocate space and format the variable in the appropriate slot. */ | |
894 | env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1); | |
895 | snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value); | |
896 | } | |
897 | ||
898 | /* | |
899 | * Reads environment variables from the given file and adds/overrides them | |
900 | * into the environment. If the file does not exist, this does nothing. | |
901 | * Otherwise, it must consist of empty lines, comments (line starts with '#') | |
902 | * and assignments of the form name=value. No other forms are allowed. | |
903 | */ | |
904 | static void | |
905 | read_environment_file(char ***env, u_int *envsize, | |
e9702f7d | 906 | const char *filename) |
3c0ef626 | 907 | { |
908 | FILE *f; | |
909 | char buf[4096]; | |
910 | char *cp, *value; | |
276b07a3 | 911 | u_int lineno = 0; |
3c0ef626 | 912 | |
913 | f = fopen(filename, "r"); | |
914 | if (!f) | |
915 | return; | |
916 | ||
917 | while (fgets(buf, sizeof(buf), f)) { | |
276b07a3 | 918 | if (++lineno > 1000) |
919 | fatal("Too many lines in environment file %s", filename); | |
3c0ef626 | 920 | for (cp = buf; *cp == ' ' || *cp == '\t'; cp++) |
921 | ; | |
922 | if (!*cp || *cp == '#' || *cp == '\n') | |
923 | continue; | |
924 | if (strchr(cp, '\n')) | |
925 | *strchr(cp, '\n') = '\0'; | |
926 | value = strchr(cp, '='); | |
927 | if (value == NULL) { | |
276b07a3 | 928 | fprintf(stderr, "Bad line %u in %.100s\n", lineno, |
929 | filename); | |
3c0ef626 | 930 | continue; |
931 | } | |
932 | /* | |
933 | * Replace the equals sign by nul, and advance value to | |
934 | * the value string. | |
935 | */ | |
936 | *value = '\0'; | |
937 | value++; | |
938 | child_set_env(env, envsize, cp, value); | |
939 | } | |
940 | fclose(f); | |
941 | } | |
942 | ||
75be3237 | 943 | #ifdef SESSION_HOOKS |
944 | #define SSH_SESSION_ENV_FILE "SSH_SESSION_ENV_FILE" | |
945 | ||
946 | typedef enum { no_op, execute, clear_env, restore_env, | |
947 | read_env, save_or_rm_env } session_action_t; | |
948 | ||
949 | static session_action_t action_order[2][5] = { | |
950 | { clear_env, read_env, execute, save_or_rm_env, restore_env }, /*shutdown*/ | |
951 | { execute, read_env, save_or_rm_env, no_op, no_op } /*startup */ | |
952 | }; | |
953 | ||
954 | static | |
955 | void execute_session_hook(char* prog, Authctxt *authctxt, | |
956 | int startup, int save) | |
957 | { | |
958 | extern char **environ; | |
959 | ||
960 | struct stat st; | |
961 | char **saved_env, **tmpenv; | |
962 | char *env_file = authctxt->session_env_file; | |
963 | int i, status = 0; | |
964 | ||
965 | for (i=0; i<5; i++) | |
966 | { | |
967 | switch (action_order[startup][i]) | |
968 | { | |
969 | case no_op: | |
970 | break; | |
971 | ||
972 | case execute: | |
973 | { | |
974 | FILE* fp; | |
975 | char buf[1000]; | |
976 | ||
977 | snprintf(buf, | |
978 | sizeof(buf), | |
979 | "%s -c '%s'", | |
980 | authctxt->pw->pw_shell, | |
981 | prog); | |
982 | ||
983 | debug("executing session hook: [%s]", buf); | |
984 | setenv(SSH_SESSION_ENV_FILE, env_file, /* overwrite = */ 1); | |
985 | ||
986 | /* flusing is recommended in the popen(3) man page, to avoid | |
987 | intermingling of output */ | |
988 | fflush(stdout); | |
989 | fflush(stderr); | |
990 | if ((fp=popen(buf, "w")) == NULL) | |
991 | { | |
992 | perror("Unable to run session hook"); | |
993 | return; | |
994 | } | |
995 | status = pclose(fp); | |
996 | debug2("session hook executed, status=%d", status); | |
997 | unsetenv(SSH_SESSION_ENV_FILE); | |
998 | } | |
999 | break; | |
1000 | ||
1001 | case clear_env: | |
1002 | saved_env = environ; | |
1003 | tmpenv = (char**) malloc(sizeof(char*)); | |
1004 | tmpenv[0] = NULL; | |
1005 | environ = tmpenv; | |
1006 | break; | |
1007 | ||
1008 | case restore_env: | |
1009 | environ = saved_env; | |
1010 | free(tmpenv); | |
1011 | break; | |
1012 | ||
1013 | case read_env: | |
1014 | if (status==0 && stat(env_file, &st)==0) | |
1015 | { | |
1016 | int envsize = 0; | |
1017 | ||
1018 | debug("reading environment from %s", env_file); | |
1019 | while (environ[envsize++]) ; | |
1020 | read_environment_file(&environ, &envsize, env_file); | |
1021 | } | |
1022 | break; | |
1023 | ||
1024 | case save_or_rm_env: | |
1025 | if (status==0 && save) | |
1026 | { | |
1027 | FILE* fp; | |
1028 | int envcount=0; | |
1029 | ||
1030 | debug2("saving environment to %s", env_file); | |
1031 | if ((fp = fopen(env_file, "w")) == NULL) /* hmm: file perms? */ | |
1032 | { | |
1033 | perror("Unable to save session hook info"); | |
1034 | } | |
1035 | while (environ[envcount]) | |
1036 | { | |
1037 | fprintf(fp, "%s\n", environ[envcount++]); | |
1038 | } | |
1039 | fflush(fp); | |
1040 | fclose(fp); | |
1041 | } | |
1042 | else if (stat(env_file, &st)==0) | |
1043 | { | |
1044 | debug2("removing environment file %s", env_file); | |
1045 | remove(env_file); | |
1046 | } | |
1047 | break; | |
1048 | } | |
1049 | } | |
1050 | ||
1051 | } | |
1052 | #endif | |
1053 | ||
7cac2b65 | 1054 | #ifdef HAVE_ETC_DEFAULT_LOGIN |
1055 | /* | |
1056 | * Return named variable from specified environment, or NULL if not present. | |
1057 | */ | |
1058 | static char * | |
1059 | child_get_env(char **env, const char *name) | |
1060 | { | |
1061 | int i; | |
1062 | size_t len; | |
1063 | ||
1064 | len = strlen(name); | |
1065 | for (i=0; env[i] != NULL; i++) | |
1066 | if (strncmp(name, env[i], len) == 0 && env[i][len] == '=') | |
1067 | return(env[i] + len + 1); | |
1068 | return NULL; | |
1069 | } | |
1070 | ||
1071 | /* | |
1072 | * Read /etc/default/login. | |
1073 | * We pick up the PATH (or SUPATH for root) and UMASK. | |
1074 | */ | |
1075 | static void | |
1076 | read_etc_default_login(char ***env, u_int *envsize, uid_t uid) | |
1077 | { | |
1078 | char **tmpenv = NULL, *var; | |
29d88157 | 1079 | u_int i, tmpenvsize = 0; |
540d72c3 | 1080 | u_long mask; |
7cac2b65 | 1081 | |
1082 | /* | |
1083 | * We don't want to copy the whole file to the child's environment, | |
1084 | * so we use a temporary environment and copy the variables we're | |
1085 | * interested in. | |
1086 | */ | |
1087 | read_environment_file(&tmpenv, &tmpenvsize, "/etc/default/login"); | |
1088 | ||
29d88157 | 1089 | if (tmpenv == NULL) |
1090 | return; | |
1091 | ||
7cac2b65 | 1092 | if (uid == 0) |
1093 | var = child_get_env(tmpenv, "SUPATH"); | |
1094 | else | |
1095 | var = child_get_env(tmpenv, "PATH"); | |
1096 | if (var != NULL) | |
1097 | child_set_env(env, envsize, "PATH", var); | |
540d72c3 | 1098 | |
7cac2b65 | 1099 | if ((var = child_get_env(tmpenv, "UMASK")) != NULL) |
1100 | if (sscanf(var, "%5lo", &mask) == 1) | |
540d72c3 | 1101 | umask((mode_t)mask); |
1102 | ||
7cac2b65 | 1103 | for (i = 0; tmpenv[i] != NULL; i++) |
1104 | xfree(tmpenv[i]); | |
1105 | xfree(tmpenv); | |
1106 | } | |
1107 | #endif /* HAVE_ETC_DEFAULT_LOGIN */ | |
1108 | ||
2ce0bfe4 | 1109 | void |
1110 | copy_environment(char **source, char ***env, u_int *envsize) | |
3c0ef626 | 1111 | { |
e9702f7d | 1112 | char *var_name, *var_val; |
3c0ef626 | 1113 | int i; |
1114 | ||
e9702f7d | 1115 | if (source == NULL) |
3c0ef626 | 1116 | return; |
1117 | ||
e9702f7d | 1118 | for(i = 0; source[i] != NULL; i++) { |
1119 | var_name = xstrdup(source[i]); | |
1120 | if ((var_val = strstr(var_name, "=")) == NULL) { | |
1121 | xfree(var_name); | |
3c0ef626 | 1122 | continue; |
3c0ef626 | 1123 | } |
e9702f7d | 1124 | *var_val++ = '\0'; |
3c0ef626 | 1125 | |
e9702f7d | 1126 | debug3("Copy environment: %s=%s", var_name, var_val); |
1127 | child_set_env(env, envsize, var_name, var_val); | |
540d72c3 | 1128 | |
e9702f7d | 1129 | xfree(var_name); |
3c0ef626 | 1130 | } |
3c0ef626 | 1131 | } |
1132 | ||
e9702f7d | 1133 | static char ** |
1134 | do_setup_env(Session *s, const char *shell) | |
3c0ef626 | 1135 | { |
3c0ef626 | 1136 | char buf[256]; |
e9702f7d | 1137 | u_int i, envsize; |
7cac2b65 | 1138 | char **env, *laddr, *path = NULL; |
e9702f7d | 1139 | struct passwd *pw = s->pw; |
3c0ef626 | 1140 | |
1141 | /* Initialize the environment. */ | |
1142 | envsize = 100; | |
1143 | env = xmalloc(envsize * sizeof(char *)); | |
1144 | env[0] = NULL; | |
1145 | ||
1146 | #ifdef HAVE_CYGWIN | |
1147 | /* | |
1148 | * The Windows environment contains some setting which are | |
1149 | * important for a running system. They must not be dropped. | |
1150 | */ | |
dfddba3d | 1151 | { |
1152 | char **p; | |
1153 | ||
1154 | p = fetch_windows_environment(); | |
1155 | copy_environment(p, &env, &envsize); | |
1156 | free_windows_environment(p); | |
1157 | } | |
3c0ef626 | 1158 | #endif |
1159 | ||
5598e598 | 1160 | #ifdef GSSAPI |
540d72c3 | 1161 | /* Allow any GSSAPI methods that we've used to alter |
5598e598 | 1162 | * the childs environment as they see fit |
1163 | */ | |
7cac2b65 | 1164 | ssh_gssapi_do_child(&env, &envsize); |
5598e598 | 1165 | #endif |
1166 | ||
3c0ef626 | 1167 | if (!options.use_login) { |
1168 | /* Set basic environment. */ | |
7e82606e | 1169 | for (i = 0; i < s->num_env; i++) |
1170 | child_set_env(&env, &envsize, s->env[i].name, | |
1171 | s->env[i].val); | |
1172 | ||
3c0ef626 | 1173 | child_set_env(&env, &envsize, "USER", pw->pw_name); |
1174 | child_set_env(&env, &envsize, "LOGNAME", pw->pw_name); | |
bfe49944 | 1175 | #ifdef _AIX |
1176 | child_set_env(&env, &envsize, "LOGIN", pw->pw_name); | |
1177 | #endif | |
3c0ef626 | 1178 | child_set_env(&env, &envsize, "HOME", pw->pw_dir); |
1179 | #ifdef HAVE_LOGIN_CAP | |
d03f4262 | 1180 | if (setusercontext(lc, pw, pw->pw_uid, LOGIN_SETPATH) < 0) |
1181 | child_set_env(&env, &envsize, "PATH", _PATH_STDPATH); | |
1182 | else | |
1183 | child_set_env(&env, &envsize, "PATH", getenv("PATH")); | |
3c0ef626 | 1184 | #else /* HAVE_LOGIN_CAP */ |
1185 | # ifndef HAVE_CYGWIN | |
1186 | /* | |
1187 | * There's no standard path on Windows. The path contains | |
1188 | * important components pointing to the system directories, | |
1189 | * needed for loading shared libraries. So the path better | |
1190 | * remains intact here. | |
1191 | */ | |
7cac2b65 | 1192 | # ifdef HAVE_ETC_DEFAULT_LOGIN |
1193 | read_etc_default_login(&env, &envsize, pw->pw_uid); | |
1194 | path = child_get_env(env, "PATH"); | |
1195 | # endif /* HAVE_ETC_DEFAULT_LOGIN */ | |
1196 | if (path == NULL || *path == '\0') { | |
540d72c3 | 1197 | child_set_env(&env, &envsize, "PATH", |
7cac2b65 | 1198 | s->pw->pw_uid == 0 ? |
1199 | SUPERUSER_PATH : _PATH_STDPATH); | |
1200 | } | |
3c0ef626 | 1201 | # endif /* HAVE_CYGWIN */ |
1202 | #endif /* HAVE_LOGIN_CAP */ | |
1203 | ||
1204 | snprintf(buf, sizeof buf, "%.200s/%.50s", | |
1205 | _PATH_MAILDIR, pw->pw_name); | |
1206 | child_set_env(&env, &envsize, "MAIL", buf); | |
1207 | ||
1208 | /* Normal systems set SHELL by default. */ | |
1209 | child_set_env(&env, &envsize, "SHELL", shell); | |
1210 | } | |
1211 | if (getenv("TZ")) | |
1212 | child_set_env(&env, &envsize, "TZ", getenv("TZ")); | |
1213 | ||
1752c22a | 1214 | #ifdef GSI /* GSI shared libs typically installed in non-system locations. */ |
1215 | { | |
1216 | char *cp; | |
1217 | ||
1218 | if ((cp = getenv("LD_LIBRARY_PATH")) != NULL) | |
1219 | child_set_env(&env, &envsize, "LD_LIBRARY_PATH", cp); | |
1220 | if ((cp = getenv("LIBPATH")) != NULL) | |
1221 | child_set_env(&env, &envsize, "LIBPATH", cp); | |
1222 | if ((cp = getenv("SHLIB_PATH")) != NULL) | |
1223 | child_set_env(&env, &envsize, "SHLIB_PATH", cp); | |
1224 | if ((cp = getenv("LD_LIBRARYN32_PATH")) != NULL) | |
1225 | child_set_env(&env, &envsize, "LD_LIBRARYN32_PATH",cp); | |
1226 | if ((cp = getenv("LD_LIBRARY64_PATH")) != NULL) | |
1227 | child_set_env(&env, &envsize, "LD_LIBRARY64_PATH",cp); | |
1228 | } | |
1229 | #endif | |
1230 | ||
3c0ef626 | 1231 | /* Set custom environment options from RSA authentication. */ |
1232 | if (!options.use_login) { | |
1233 | while (custom_environment) { | |
1234 | struct envstring *ce = custom_environment; | |
d03f4262 | 1235 | char *str = ce->s; |
e9702f7d | 1236 | |
d03f4262 | 1237 | for (i = 0; str[i] != '=' && str[i]; i++) |
3c0ef626 | 1238 | ; |
d03f4262 | 1239 | if (str[i] == '=') { |
1240 | str[i] = 0; | |
1241 | child_set_env(&env, &envsize, str, str + i + 1); | |
3c0ef626 | 1242 | } |
1243 | custom_environment = ce->next; | |
1244 | xfree(ce->s); | |
1245 | xfree(ce); | |
1246 | } | |
1247 | } | |
1248 | ||
d03f4262 | 1249 | /* SSH_CLIENT deprecated */ |
3c0ef626 | 1250 | snprintf(buf, sizeof buf, "%.50s %d %d", |
e9702f7d | 1251 | get_remote_ipaddr(), get_remote_port(), get_local_port()); |
3c0ef626 | 1252 | child_set_env(&env, &envsize, "SSH_CLIENT", buf); |
1253 | ||
bfe49944 | 1254 | laddr = get_local_ipaddr(packet_get_connection_in()); |
d03f4262 | 1255 | snprintf(buf, sizeof buf, "%.50s %d %.50s %d", |
bfe49944 | 1256 | get_remote_ipaddr(), get_remote_port(), laddr, get_local_port()); |
1257 | xfree(laddr); | |
d03f4262 | 1258 | child_set_env(&env, &envsize, "SSH_CONNECTION", buf); |
1259 | ||
3c0ef626 | 1260 | if (s->ttyfd != -1) |
1261 | child_set_env(&env, &envsize, "SSH_TTY", s->tty); | |
1262 | if (s->term) | |
1263 | child_set_env(&env, &envsize, "TERM", s->term); | |
1264 | if (s->display) | |
1265 | child_set_env(&env, &envsize, "DISPLAY", s->display); | |
1266 | if (original_command) | |
1267 | child_set_env(&env, &envsize, "SSH_ORIGINAL_COMMAND", | |
1268 | original_command); | |
1269 | ||
d03f4262 | 1270 | #ifdef _UNICOS |
1271 | if (cray_tmpdir[0] != '\0') | |
1272 | child_set_env(&env, &envsize, "TMPDIR", cray_tmpdir); | |
1273 | #endif /* _UNICOS */ | |
1274 | ||
dfddba3d | 1275 | /* |
1276 | * Since we clear KRB5CCNAME at startup, if it's set now then it | |
1277 | * must have been set by a native authentication method (eg AIX or | |
1278 | * SIA), so copy it to the child. | |
1279 | */ | |
1280 | { | |
1281 | char *cp; | |
1282 | ||
1283 | if ((cp = getenv("KRB5CCNAME")) != NULL) | |
1284 | child_set_env(&env, &envsize, "KRB5CCNAME", cp); | |
1285 | } | |
1286 | ||
3c0ef626 | 1287 | #ifdef _AIX |
e9702f7d | 1288 | { |
1289 | char *cp; | |
1290 | ||
1291 | if ((cp = getenv("AUTHSTATE")) != NULL) | |
1292 | child_set_env(&env, &envsize, "AUTHSTATE", cp); | |
e9702f7d | 1293 | read_environment_file(&env, &envsize, "/etc/environment"); |
1294 | } | |
3c0ef626 | 1295 | #endif |
3c0ef626 | 1296 | #ifdef KRB5 |
12a403af | 1297 | if (s->authctxt->krb5_ccname) |
3c0ef626 | 1298 | child_set_env(&env, &envsize, "KRB5CCNAME", |
12a403af | 1299 | s->authctxt->krb5_ccname); |
3c0ef626 | 1300 | #endif |
1301 | #ifdef USE_PAM | |
d03f4262 | 1302 | /* |
1303 | * Pull in any environment variables that may have | |
1304 | * been set by PAM. | |
1305 | */ | |
7cac2b65 | 1306 | if (options.use_pam) { |
540d72c3 | 1307 | char **p; |
d03f4262 | 1308 | |
540d72c3 | 1309 | p = fetch_pam_child_environment(); |
1310 | copy_environment(p, &env, &envsize); | |
1311 | free_pam_environment(p); | |
1312 | ||
1313 | p = fetch_pam_environment(); | |
d03f4262 | 1314 | copy_environment(p, &env, &envsize); |
1315 | free_pam_environment(p); | |
1316 | } | |
3c0ef626 | 1317 | #endif /* USE_PAM */ |
1318 | ||
44a053a3 | 1319 | if (auth_sock_name != NULL) |
3c0ef626 | 1320 | child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME, |
44a053a3 | 1321 | auth_sock_name); |
3c0ef626 | 1322 | |
1323 | /* read $HOME/.ssh/environment. */ | |
d03f4262 | 1324 | if (options.permit_user_env && !options.use_login) { |
3c0ef626 | 1325 | snprintf(buf, sizeof buf, "%.200s/.ssh/environment", |
d03f4262 | 1326 | strcmp(pw->pw_dir, "/") ? pw->pw_dir : ""); |
3c0ef626 | 1327 | read_environment_file(&env, &envsize, buf); |
1328 | } | |
1329 | if (debug_flag) { | |
1330 | /* dump the environment */ | |
1331 | fprintf(stderr, "Environment:\n"); | |
1332 | for (i = 0; env[i]; i++) | |
1333 | fprintf(stderr, " %.200s\n", env[i]); | |
1334 | } | |
e9702f7d | 1335 | return env; |
1336 | } | |
1337 | ||
1338 | /* | |
1339 | * Run $HOME/.ssh/rc, /etc/ssh/sshrc, or xauth (whichever is found | |
1340 | * first in this order). | |
1341 | */ | |
1342 | static void | |
1343 | do_rc_files(Session *s, const char *shell) | |
1344 | { | |
1345 | FILE *f = NULL; | |
1346 | char cmd[1024]; | |
1347 | int do_xauth; | |
1348 | struct stat st; | |
1349 | ||
1350 | do_xauth = | |
1351 | s->display != NULL && s->auth_proto != NULL && s->auth_data != NULL; | |
1352 | ||
1353 | /* ignore _PATH_SSH_USER_RC for subsystems */ | |
1354 | if (!s->is_subsystem && (stat(_PATH_SSH_USER_RC, &st) >= 0)) { | |
1355 | snprintf(cmd, sizeof cmd, "%s -c '%s %s'", | |
1356 | shell, _PATH_BSHELL, _PATH_SSH_USER_RC); | |
1357 | if (debug_flag) | |
1358 | fprintf(stderr, "Running %s\n", cmd); | |
1359 | f = popen(cmd, "w"); | |
1360 | if (f) { | |
1361 | if (do_xauth) | |
1362 | fprintf(f, "%s %s\n", s->auth_proto, | |
1363 | s->auth_data); | |
1364 | pclose(f); | |
1365 | } else | |
1366 | fprintf(stderr, "Could not run %s\n", | |
1367 | _PATH_SSH_USER_RC); | |
1368 | } else if (stat(_PATH_SSH_SYSTEM_RC, &st) >= 0) { | |
1369 | if (debug_flag) | |
1370 | fprintf(stderr, "Running %s %s\n", _PATH_BSHELL, | |
1371 | _PATH_SSH_SYSTEM_RC); | |
1372 | f = popen(_PATH_BSHELL " " _PATH_SSH_SYSTEM_RC, "w"); | |
1373 | if (f) { | |
1374 | if (do_xauth) | |
1375 | fprintf(f, "%s %s\n", s->auth_proto, | |
1376 | s->auth_data); | |
1377 | pclose(f); | |
1378 | } else | |
1379 | fprintf(stderr, "Could not run %s\n", | |
1380 | _PATH_SSH_SYSTEM_RC); | |
1381 | } else if (do_xauth && options.xauth_location != NULL) { | |
1382 | /* Add authority data to .Xauthority if appropriate. */ | |
1383 | if (debug_flag) { | |
1384 | fprintf(stderr, | |
bfe49944 | 1385 | "Running %.500s remove %.100s\n", |
540d72c3 | 1386 | options.xauth_location, s->auth_display); |
bfe49944 | 1387 | fprintf(stderr, |
1388 | "%.500s add %.100s %.100s %.100s\n", | |
e9702f7d | 1389 | options.xauth_location, s->auth_display, |
1390 | s->auth_proto, s->auth_data); | |
1391 | } | |
1392 | snprintf(cmd, sizeof cmd, "%s -q -", | |
1393 | options.xauth_location); | |
1394 | f = popen(cmd, "w"); | |
1395 | if (f) { | |
bfe49944 | 1396 | fprintf(f, "remove %s\n", |
1397 | s->auth_display); | |
e9702f7d | 1398 | fprintf(f, "add %s %s %s\n", |
1399 | s->auth_display, s->auth_proto, | |
1400 | s->auth_data); | |
1401 | pclose(f); | |
1402 | } else { | |
1403 | fprintf(stderr, "Could not run %s\n", | |
1404 | cmd); | |
1405 | } | |
1406 | } | |
1407 | } | |
1408 | ||
1409 | static void | |
1410 | do_nologin(struct passwd *pw) | |
1411 | { | |
1412 | FILE *f = NULL; | |
1413 | char buf[1024]; | |
1414 | ||
1415 | #ifdef HAVE_LOGIN_CAP | |
1416 | if (!login_getcapbool(lc, "ignorenologin", 0) && pw->pw_uid) | |
1417 | f = fopen(login_getcapstr(lc, "nologin", _PATH_NOLOGIN, | |
1418 | _PATH_NOLOGIN), "r"); | |
1419 | #else | |
1420 | if (pw->pw_uid) | |
1421 | f = fopen(_PATH_NOLOGIN, "r"); | |
1422 | #endif | |
1423 | if (f) { | |
1424 | /* /etc/nologin exists. Print its contents and exit. */ | |
7cac2b65 | 1425 | logit("User %.100s not allowed because %s exists", |
d03f4262 | 1426 | pw->pw_name, _PATH_NOLOGIN); |
e9702f7d | 1427 | while (fgets(buf, sizeof(buf), f)) |
1428 | fputs(buf, stderr); | |
1429 | fclose(f); | |
bfe49944 | 1430 | fflush(NULL); |
e9702f7d | 1431 | exit(254); |
1432 | } | |
1433 | } | |
1434 | ||
1435 | /* Set login name, uid, gid, and groups. */ | |
350391c5 | 1436 | void |
e9702f7d | 1437 | do_setusercontext(struct passwd *pw) |
1438 | { | |
bfe49944 | 1439 | #ifndef HAVE_CYGWIN |
1440 | if (getuid() == 0 || geteuid() == 0) | |
e9702f7d | 1441 | #endif /* HAVE_CYGWIN */ |
bfe49944 | 1442 | { |
1443 | ||
44a053a3 | 1444 | #ifdef HAVE_SETPCRED |
7cac2b65 | 1445 | if (setpcred(pw->pw_name, (char **)NULL) == -1) |
1446 | fatal("Failed to set process credentials"); | |
44a053a3 | 1447 | #endif /* HAVE_SETPCRED */ |
e9702f7d | 1448 | #ifdef HAVE_LOGIN_CAP |
d03f4262 | 1449 | # ifdef __bsdi__ |
276b07a3 | 1450 | setpgid(0, 0); |
d03f4262 | 1451 | # endif |
dfddba3d | 1452 | #ifdef GSSAPI |
1453 | if (options.gss_authentication) { | |
1454 | temporarily_use_uid(pw); | |
1455 | ssh_gssapi_storecreds(); | |
1456 | restore_uid(); | |
1457 | } | |
1458 | #endif | |
540d72c3 | 1459 | # ifdef USE_PAM |
1460 | if (options.use_pam) { | |
1461 | do_pam_session(); | |
1462 | do_pam_setcred(0); | |
1463 | } | |
1464 | # endif /* USE_PAM */ | |
e9702f7d | 1465 | if (setusercontext(lc, pw, pw->pw_uid, |
1466 | (LOGIN_SETALL & ~LOGIN_SETPATH)) < 0) { | |
1467 | perror("unable to set user context"); | |
1468 | exit(1); | |
1469 | } | |
1470 | #else | |
1471 | # if defined(HAVE_GETLUID) && defined(HAVE_SETLUID) | |
1472 | /* Sets login uid for accounting */ | |
1473 | if (getluid() == -1 && setluid(pw->pw_uid) == -1) | |
1474 | error("setluid: %s", strerror(errno)); | |
1475 | # endif /* defined(HAVE_GETLUID) && defined(HAVE_SETLUID) */ | |
1476 | ||
1477 | if (setlogin(pw->pw_name) < 0) | |
1478 | error("setlogin failed: %s", strerror(errno)); | |
1479 | if (setgid(pw->pw_gid) < 0) { | |
1480 | perror("setgid"); | |
1481 | exit(1); | |
1482 | } | |
1483 | /* Initialize the group list. */ | |
1484 | if (initgroups(pw->pw_name, pw->pw_gid) < 0) { | |
1485 | perror("initgroups"); | |
1486 | exit(1); | |
1487 | } | |
1488 | endgrent(); | |
dfddba3d | 1489 | #ifdef GSSAPI |
1490 | if (options.gss_authentication) { | |
1491 | temporarily_use_uid(pw); | |
1492 | ssh_gssapi_storecreds(); | |
1493 | restore_uid(); | |
1494 | } | |
1495 | #endif | |
e9702f7d | 1496 | # ifdef USE_PAM |
1497 | /* | |
540d72c3 | 1498 | * PAM credentials may take the form of supplementary groups. |
e9702f7d | 1499 | * These will have been wiped by the above initgroups() call. |
1500 | * Reestablish them here. | |
1501 | */ | |
7cac2b65 | 1502 | if (options.use_pam) { |
1503 | do_pam_session(); | |
1504 | do_pam_setcred(0); | |
1505 | } | |
e9702f7d | 1506 | # endif /* USE_PAM */ |
1507 | # if defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) | |
1508 | irix_setusercontext(pw); | |
1509 | # endif /* defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) */ | |
276b07a3 | 1510 | # ifdef _AIX |
d03f4262 | 1511 | aix_usrinfo(pw); |
276b07a3 | 1512 | # endif /* _AIX */ |
2ce0bfe4 | 1513 | #if defined(HAVE_LIBIAF) && !defined(BROKEN_LIBIAF) |
1514 | if (set_id(pw->pw_name) != 0) { | |
1515 | exit(1); | |
1516 | } | |
1517 | #endif /* HAVE_LIBIAF && !BROKEN_LIBIAF */ | |
e9702f7d | 1518 | /* Permanently switch to the desired uid. */ |
1519 | permanently_set_uid(pw); | |
1520 | #endif | |
1521 | } | |
bfe49944 | 1522 | |
1523 | #ifdef HAVE_CYGWIN | |
1524 | if (is_winnt) | |
1525 | #endif | |
e9702f7d | 1526 | if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid) |
1527 | fatal("Failed to set uids to %u.", (u_int) pw->pw_uid); | |
1528 | } | |
1529 | ||
540d72c3 | 1530 | static void |
1531 | do_pwchange(Session *s) | |
1532 | { | |
7e82606e | 1533 | fflush(NULL); |
540d72c3 | 1534 | fprintf(stderr, "WARNING: Your password has expired.\n"); |
1535 | if (s->ttyfd != -1) { | |
7e82606e | 1536 | fprintf(stderr, |
540d72c3 | 1537 | "You must change your password now and login again!\n"); |
dfddba3d | 1538 | #ifdef PASSWD_NEEDS_USERNAME |
1539 | execl(_PATH_PASSWD_PROG, "passwd", s->pw->pw_name, | |
1540 | (char *)NULL); | |
1541 | #else | |
540d72c3 | 1542 | execl(_PATH_PASSWD_PROG, "passwd", (char *)NULL); |
dfddba3d | 1543 | #endif |
540d72c3 | 1544 | perror("passwd"); |
1545 | } else { | |
1546 | fprintf(stderr, | |
1547 | "Password change required but no TTY available.\n"); | |
1548 | } | |
1549 | exit(1); | |
1550 | } | |
1551 | ||
350391c5 | 1552 | static void |
1553 | launch_login(struct passwd *pw, const char *hostname) | |
1554 | { | |
1555 | /* Launch login(1). */ | |
1556 | ||
44a053a3 | 1557 | execl(LOGIN_PROGRAM, "login", "-h", hostname, |
350391c5 | 1558 | #ifdef xxxLOGIN_NEEDS_TERM |
44a053a3 | 1559 | (s->term ? s->term : "unknown"), |
350391c5 | 1560 | #endif /* LOGIN_NEEDS_TERM */ |
1561 | #ifdef LOGIN_NO_ENDOPT | |
1562 | "-p", "-f", pw->pw_name, (char *)NULL); | |
1563 | #else | |
1564 | "-p", "-f", "--", pw->pw_name, (char *)NULL); | |
1565 | #endif | |
1566 | ||
1567 | /* Login couldn't be executed, die. */ | |
1568 | ||
1569 | perror("login"); | |
1570 | exit(1); | |
1571 | } | |
1572 | ||
540d72c3 | 1573 | static void |
1574 | child_close_fds(void) | |
1575 | { | |
1576 | int i; | |
1577 | ||
1578 | if (packet_get_connection_in() == packet_get_connection_out()) | |
1579 | close(packet_get_connection_in()); | |
1580 | else { | |
1581 | close(packet_get_connection_in()); | |
1582 | close(packet_get_connection_out()); | |
1583 | } | |
1584 | /* | |
1585 | * Close all descriptors related to channels. They will still remain | |
1586 | * open in the parent. | |
1587 | */ | |
1588 | /* XXX better use close-on-exec? -markus */ | |
1589 | channel_close_all(); | |
1590 | ||
1591 | /* | |
1592 | * Close any extra file descriptors. Note that there may still be | |
1593 | * descriptors left by system functions. They will be closed later. | |
1594 | */ | |
1595 | endpwent(); | |
1596 | ||
1597 | /* | |
1598 | * Close any extra open file descriptors so that we don\'t have them | |
1599 | * hanging around in clients. Note that we want to do this after | |
1600 | * initgroups, because at least on Solaris 2.3 it leaves file | |
1601 | * descriptors open. | |
1602 | */ | |
1603 | for (i = 3; i < 64; i++) | |
1604 | close(i); | |
1605 | } | |
1606 | ||
e9702f7d | 1607 | /* |
1608 | * Performs common processing for the child, such as setting up the | |
1609 | * environment, closing extra file descriptors, setting the user and group | |
1610 | * ids, and executing the command or shell. | |
1611 | */ | |
1612 | void | |
1613 | do_child(Session *s, const char *command) | |
1614 | { | |
1615 | extern char **environ; | |
1616 | char **env; | |
1617 | char *argv[10]; | |
1618 | const char *shell, *shell0, *hostname = NULL; | |
1619 | struct passwd *pw = s->pw; | |
e9702f7d | 1620 | |
62eb343a | 1621 | #ifdef AFS_KRB5 |
1622 | /* Default place to look for aklog. */ | |
1623 | #ifdef AKLOG_PATH | |
1624 | #define KPROGDIR AKLOG_PATH | |
1625 | #else | |
1626 | #define KPROGDIR "/usr/bin/aklog" | |
1627 | #endif /* AKLOG_PATH */ | |
1628 | ||
1629 | struct stat st; | |
1630 | char *aklog_path; | |
1631 | #endif /* AFS_KRB5 */ | |
1632 | ||
e9702f7d | 1633 | /* remove hostkey from the child's memory */ |
1634 | destroy_sensitive_data(); | |
1635 | ||
540d72c3 | 1636 | /* Force a password change */ |
1637 | if (s->authctxt->force_pwchange) { | |
1638 | do_setusercontext(pw); | |
1639 | child_close_fds(); | |
1640 | do_pwchange(s); | |
1641 | exit(1); | |
1642 | } | |
1643 | ||
e9702f7d | 1644 | /* login(1) is only called if we execute the login shell */ |
1645 | if (options.use_login && command != NULL) | |
1646 | options.use_login = 0; | |
1647 | ||
d03f4262 | 1648 | #ifdef _UNICOS |
1649 | cray_setup(pw->pw_uid, pw->pw_name, command); | |
1650 | #endif /* _UNICOS */ | |
1651 | ||
e9702f7d | 1652 | /* |
1653 | * Login(1) does this as well, and it needs uid 0 for the "-h" | |
1654 | * switch, so we let login(1) to this for us. | |
1655 | */ | |
1656 | if (!options.use_login) { | |
1657 | #ifdef HAVE_OSF_SIA | |
bfe49944 | 1658 | session_setup_sia(pw, s->ttyfd == -1 ? NULL : s->tty); |
e9702f7d | 1659 | if (!check_quietlogin(s, command)) |
1660 | do_motd(); | |
1661 | #else /* HAVE_OSF_SIA */ | |
1662 | do_nologin(pw); | |
e9702f7d | 1663 | do_setusercontext(pw); |
7e82606e | 1664 | /* |
1665 | * PAM session modules in do_setusercontext may have | |
1666 | * generated messages, so if this in an interactive | |
1667 | * login then display them too. | |
1668 | */ | |
dfddba3d | 1669 | if (!check_quietlogin(s, command)) |
7e82606e | 1670 | display_loginmsg(); |
e9702f7d | 1671 | #endif /* HAVE_OSF_SIA */ |
1672 | } | |
1673 | ||
dfddba3d | 1674 | #ifdef USE_PAM |
8b32eddc | 1675 | if (options.use_pam && !options.use_login && !is_pam_session_open()) { |
1676 | debug3("PAM session not opened, exiting"); | |
dfddba3d | 1677 | display_loginmsg(); |
1678 | exit(254); | |
1679 | } | |
1680 | #endif | |
1681 | ||
e9702f7d | 1682 | /* |
1683 | * Get the shell from the password data. An empty shell field is | |
1684 | * legal, and means /bin/sh. | |
1685 | */ | |
1686 | shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell; | |
bfe49944 | 1687 | |
1688 | /* | |
1689 | * Make sure $SHELL points to the shell from the password file, | |
1690 | * even if shell is overridden from login.conf | |
1691 | */ | |
1692 | env = do_setup_env(s, shell); | |
1693 | ||
e9702f7d | 1694 | #ifdef HAVE_LOGIN_CAP |
1695 | shell = login_getcapstr(lc, "shell", (char *)shell, (char *)shell); | |
1696 | #endif | |
1697 | ||
3c0ef626 | 1698 | /* we have to stash the hostname before we close our socket. */ |
1699 | if (options.use_login) | |
1700 | hostname = get_remote_name_or_ip(utmp_len, | |
7cac2b65 | 1701 | options.use_dns); |
3c0ef626 | 1702 | /* |
1703 | * Close the connection descriptors; note that this is the child, and | |
1704 | * the server will still have the socket open, and it is important | |
1705 | * that we do not shutdown it. Note that the descriptors cannot be | |
1706 | * closed before building the environment, as we call | |
1707 | * get_remote_ipaddr there. | |
1708 | */ | |
540d72c3 | 1709 | child_close_fds(); |
3c0ef626 | 1710 | |
1711 | /* | |
540d72c3 | 1712 | * Must take new environment into use so that .ssh/rc, |
1713 | * /etc/ssh/sshrc and xauth are run in the proper environment. | |
3c0ef626 | 1714 | */ |
540d72c3 | 1715 | environ = env; |
3c0ef626 | 1716 | |
540d72c3 | 1717 | #if defined(KRB5) && defined(USE_AFS) |
3c0ef626 | 1718 | /* |
540d72c3 | 1719 | * At this point, we check to see if AFS is active and if we have |
1720 | * a valid Kerberos 5 TGT. If so, it seems like a good idea to see | |
1721 | * if we can (and need to) extend the ticket into an AFS token. If | |
1722 | * we don't do this, we run into potential problems if the user's | |
1723 | * home directory is in AFS and it's not world-readable. | |
3c0ef626 | 1724 | */ |
3c0ef626 | 1725 | |
540d72c3 | 1726 | if (options.kerberos_get_afs_token && k_hasafs() && |
2ce0bfe4 | 1727 | (s->authctxt->krb5_ctx != NULL)) { |
540d72c3 | 1728 | char cell[64]; |
1729 | ||
1730 | debug("Getting AFS token"); | |
1731 | ||
1732 | k_setpag(); | |
1733 | ||
1734 | if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0) | |
1735 | krb5_afslog(s->authctxt->krb5_ctx, | |
1736 | s->authctxt->krb5_fwd_ccache, cell, NULL); | |
1737 | ||
1738 | krb5_afslog_home(s->authctxt->krb5_ctx, | |
1739 | s->authctxt->krb5_fwd_ccache, NULL, NULL, pw->pw_dir); | |
1740 | } | |
1741 | #endif | |
3c0ef626 | 1742 | |
62eb343a | 1743 | #ifdef AFS_KRB5 |
1744 | ||
1745 | /* User has authenticated, and if a ticket was going to be | |
1746 | * passed we would have it. KRB5CCNAME should already be set. | |
1747 | * Now try to get an AFS token using aklog. | |
1748 | */ | |
1749 | if (k_hasafs()) { /* Do we have AFS? */ | |
1750 | ||
1751 | aklog_path = xstrdup(KPROGDIR); | |
1752 | ||
1753 | /* | |
1754 | * Make sure it exists before we try to run it | |
1755 | */ | |
1756 | if (stat(aklog_path, &st) == 0) { | |
1757 | debug("Running %s to get afs token.",aklog_path); | |
1758 | system(aklog_path); | |
1759 | } else { | |
1760 | debug("%s does not exist.",aklog_path); | |
1761 | } | |
1762 | ||
1763 | xfree(aklog_path); | |
1764 | } | |
1765 | #endif /* AFS_KRB5 */ | |
1766 | ||
75be3237 | 1767 | #ifdef SESSION_HOOKS |
1768 | if (options.session_hooks_allow && | |
1769 | options.session_hooks_startup_cmd) | |
1770 | { | |
1771 | execute_session_hook(options.session_hooks_startup_cmd, | |
1772 | s->authctxt, | |
1773 | /* startup = */ 1, | |
1774 | options.session_hooks_shutdown_cmd != NULL); | |
1775 | } | |
1776 | #endif | |
3c0ef626 | 1777 | |
1778 | /* Change current directory to the user\'s home directory. */ | |
1779 | if (chdir(pw->pw_dir) < 0) { | |
1780 | fprintf(stderr, "Could not chdir to home directory %s: %s\n", | |
1781 | pw->pw_dir, strerror(errno)); | |
1782 | #ifdef HAVE_LOGIN_CAP | |
1783 | if (login_getcapbool(lc, "requirehome", 0)) | |
1784 | exit(1); | |
1785 | #endif | |
1786 | } | |
1787 | ||
e9702f7d | 1788 | if (!options.use_login) |
1789 | do_rc_files(s, shell); | |
3c0ef626 | 1790 | |
1791 | /* restore SIGPIPE for child */ | |
1792 | signal(SIGPIPE, SIG_DFL); | |
1793 | ||
e9702f7d | 1794 | if (options.use_login) { |
350391c5 | 1795 | launch_login(pw, hostname); |
1796 | /* NEVERREACHED */ | |
e9702f7d | 1797 | } |
1798 | ||
1799 | /* Get the last component of the shell name. */ | |
1800 | if ((shell0 = strrchr(shell, '/')) != NULL) | |
1801 | shell0++; | |
1802 | else | |
1803 | shell0 = shell; | |
1804 | ||
3c0ef626 | 1805 | /* |
1806 | * If we have no command, execute the shell. In this case, the shell | |
1807 | * name to be passed in argv[0] is preceded by '-' to indicate that | |
1808 | * this is a login shell. | |
1809 | */ | |
1810 | if (!command) { | |
e9702f7d | 1811 | char argv0[256]; |
3c0ef626 | 1812 | |
e9702f7d | 1813 | /* Start the shell. Set initial character to '-'. */ |
1814 | argv0[0] = '-'; | |
3c0ef626 | 1815 | |
e9702f7d | 1816 | if (strlcpy(argv0 + 1, shell0, sizeof(argv0) - 1) |
1817 | >= sizeof(argv0) - 1) { | |
1818 | errno = EINVAL; | |
3c0ef626 | 1819 | perror(shell); |
1820 | exit(1); | |
e9702f7d | 1821 | } |
3c0ef626 | 1822 | |
e9702f7d | 1823 | /* Execute the shell. */ |
1824 | argv[0] = argv0; | |
1825 | argv[1] = NULL; | |
5ab1e3bd | 1826 | execve(shell, argv, environ); |
3c0ef626 | 1827 | |
e9702f7d | 1828 | /* Executing the shell failed. */ |
1829 | perror(shell); | |
1830 | exit(1); | |
3c0ef626 | 1831 | } |
1832 | /* | |
1833 | * Execute the command using the user's shell. This uses the -c | |
1834 | * option to execute the command. | |
1835 | */ | |
e9702f7d | 1836 | argv[0] = (char *) shell0; |
3c0ef626 | 1837 | argv[1] = "-c"; |
1838 | argv[2] = (char *) command; | |
1839 | argv[3] = NULL; | |
5ab1e3bd | 1840 | execve(shell, argv, environ); |
3c0ef626 | 1841 | perror(shell); |
1842 | exit(1); | |
1843 | } | |
1844 | ||
1845 | Session * | |
1846 | session_new(void) | |
1847 | { | |
1848 | int i; | |
1849 | static int did_init = 0; | |
1850 | if (!did_init) { | |
1851 | debug("session_new: init"); | |
e9702f7d | 1852 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1853 | sessions[i].used = 0; |
1854 | } | |
1855 | did_init = 1; | |
1856 | } | |
e9702f7d | 1857 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1858 | Session *s = &sessions[i]; |
1859 | if (! s->used) { | |
1860 | memset(s, 0, sizeof(*s)); | |
1861 | s->chanid = -1; | |
1862 | s->ptyfd = -1; | |
1863 | s->ttyfd = -1; | |
1864 | s->used = 1; | |
1865 | s->self = i; | |
2ce0bfe4 | 1866 | s->x11_chanids = NULL; |
3c0ef626 | 1867 | debug("session_new: session %d", i); |
1868 | return s; | |
1869 | } | |
1870 | } | |
1871 | return NULL; | |
1872 | } | |
1873 | ||
1874 | static void | |
1875 | session_dump(void) | |
1876 | { | |
1877 | int i; | |
e9702f7d | 1878 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1879 | Session *s = &sessions[i]; |
44a053a3 | 1880 | debug("dump: used %d session %d %p channel %d pid %ld", |
3c0ef626 | 1881 | s->used, |
1882 | s->self, | |
1883 | s, | |
1884 | s->chanid, | |
44a053a3 | 1885 | (long)s->pid); |
3c0ef626 | 1886 | } |
1887 | } | |
1888 | ||
1889 | int | |
1890 | session_open(Authctxt *authctxt, int chanid) | |
1891 | { | |
1892 | Session *s = session_new(); | |
1893 | debug("session_open: channel %d", chanid); | |
1894 | if (s == NULL) { | |
1895 | error("no more sessions"); | |
1896 | return 0; | |
1897 | } | |
1898 | s->authctxt = authctxt; | |
1899 | s->pw = authctxt->pw; | |
540d72c3 | 1900 | if (s->pw == NULL || !authctxt->valid) |
3c0ef626 | 1901 | fatal("no user for session %d", s->self); |
1902 | debug("session_open: session %d: link with channel %d", s->self, chanid); | |
1903 | s->chanid = chanid; | |
1904 | return 1; | |
1905 | } | |
1906 | ||
350391c5 | 1907 | Session * |
1908 | session_by_tty(char *tty) | |
1909 | { | |
1910 | int i; | |
1911 | for (i = 0; i < MAX_SESSIONS; i++) { | |
1912 | Session *s = &sessions[i]; | |
1913 | if (s->used && s->ttyfd != -1 && strcmp(s->tty, tty) == 0) { | |
1914 | debug("session_by_tty: session %d tty %s", i, tty); | |
1915 | return s; | |
1916 | } | |
1917 | } | |
1918 | debug("session_by_tty: unknown tty %.100s", tty); | |
1919 | session_dump(); | |
1920 | return NULL; | |
1921 | } | |
1922 | ||
3c0ef626 | 1923 | static Session * |
1924 | session_by_channel(int id) | |
1925 | { | |
1926 | int i; | |
e9702f7d | 1927 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1928 | Session *s = &sessions[i]; |
1929 | if (s->used && s->chanid == id) { | |
1930 | debug("session_by_channel: session %d channel %d", i, id); | |
1931 | return s; | |
1932 | } | |
1933 | } | |
1934 | debug("session_by_channel: unknown channel %d", id); | |
1935 | session_dump(); | |
1936 | return NULL; | |
1937 | } | |
1938 | ||
2ce0bfe4 | 1939 | static Session * |
1940 | session_by_x11_channel(int id) | |
1941 | { | |
1942 | int i, j; | |
1943 | ||
1944 | for (i = 0; i < MAX_SESSIONS; i++) { | |
1945 | Session *s = &sessions[i]; | |
1946 | ||
1947 | if (s->x11_chanids == NULL || !s->used) | |
1948 | continue; | |
1949 | for (j = 0; s->x11_chanids[j] != -1; j++) { | |
1950 | if (s->x11_chanids[j] == id) { | |
1951 | debug("session_by_x11_channel: session %d " | |
1952 | "channel %d", s->self, id); | |
1953 | return s; | |
1954 | } | |
1955 | } | |
1956 | } | |
1957 | debug("session_by_x11_channel: unknown channel %d", id); | |
1958 | session_dump(); | |
1959 | return NULL; | |
1960 | } | |
1961 | ||
3c0ef626 | 1962 | static Session * |
1963 | session_by_pid(pid_t pid) | |
1964 | { | |
1965 | int i; | |
44a053a3 | 1966 | debug("session_by_pid: pid %ld", (long)pid); |
e9702f7d | 1967 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1968 | Session *s = &sessions[i]; |
1969 | if (s->used && s->pid == pid) | |
1970 | return s; | |
1971 | } | |
44a053a3 | 1972 | error("session_by_pid: unknown pid %ld", (long)pid); |
3c0ef626 | 1973 | session_dump(); |
1974 | return NULL; | |
1975 | } | |
1976 | ||
1977 | static int | |
1978 | session_window_change_req(Session *s) | |
1979 | { | |
1980 | s->col = packet_get_int(); | |
1981 | s->row = packet_get_int(); | |
1982 | s->xpixel = packet_get_int(); | |
1983 | s->ypixel = packet_get_int(); | |
e9702f7d | 1984 | packet_check_eom(); |
3c0ef626 | 1985 | pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel); |
1986 | return 1; | |
1987 | } | |
1988 | ||
1989 | static int | |
1990 | session_pty_req(Session *s) | |
1991 | { | |
1992 | u_int len; | |
1993 | int n_bytes; | |
1994 | ||
1995 | if (no_pty_flag) { | |
1996 | debug("Allocating a pty not permitted for this authentication."); | |
1997 | return 0; | |
1998 | } | |
1999 | if (s->ttyfd != -1) { | |
2000 | packet_disconnect("Protocol error: you already have a pty."); | |
2001 | return 0; | |
2002 | } | |
2003 | ||
2004 | s->term = packet_get_string(&len); | |
2005 | ||
2006 | if (compat20) { | |
2007 | s->col = packet_get_int(); | |
2008 | s->row = packet_get_int(); | |
2009 | } else { | |
2010 | s->row = packet_get_int(); | |
2011 | s->col = packet_get_int(); | |
2012 | } | |
2013 | s->xpixel = packet_get_int(); | |
2014 | s->ypixel = packet_get_int(); | |
2015 | ||
2016 | if (strcmp(s->term, "") == 0) { | |
2017 | xfree(s->term); | |
2018 | s->term = NULL; | |
2019 | } | |
2020 | ||
2021 | /* Allocate a pty and open it. */ | |
2022 | debug("Allocating pty."); | |
350391c5 | 2023 | if (!PRIVSEP(pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty)))) { |
3c0ef626 | 2024 | if (s->term) |
2025 | xfree(s->term); | |
2026 | s->term = NULL; | |
2027 | s->ptyfd = -1; | |
2028 | s->ttyfd = -1; | |
2029 | error("session_pty_req: session %d alloc failed", s->self); | |
2030 | return 0; | |
2031 | } | |
2032 | debug("session_pty_req: session %d alloc %s", s->self, s->tty); | |
2033 | ||
2034 | /* for SSH1 the tty modes length is not given */ | |
2035 | if (!compat20) | |
2036 | n_bytes = packet_remaining(); | |
2037 | tty_parse_modes(s->ttyfd, &n_bytes); | |
2038 | ||
350391c5 | 2039 | if (!use_privsep) |
2040 | pty_setowner(s->pw, s->tty); | |
3c0ef626 | 2041 | |
2042 | /* Set window size from the packet. */ | |
2043 | pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel); | |
2044 | ||
e9702f7d | 2045 | packet_check_eom(); |
3c0ef626 | 2046 | session_proctitle(s); |
2047 | return 1; | |
2048 | } | |
2049 | ||
2050 | static int | |
2051 | session_subsystem_req(Session *s) | |
2052 | { | |
2053 | struct stat st; | |
2054 | u_int len; | |
2055 | int success = 0; | |
2056 | char *cmd, *subsys = packet_get_string(&len); | |
2ce0bfe4 | 2057 | u_int i; |
3c0ef626 | 2058 | |
e9702f7d | 2059 | packet_check_eom(); |
7cac2b65 | 2060 | logit("subsystem request for %.100s", subsys); |
3c0ef626 | 2061 | |
2062 | for (i = 0; i < options.num_subsystems; i++) { | |
2063 | if (strcmp(subsys, options.subsystem_name[i]) == 0) { | |
2064 | cmd = options.subsystem_command[i]; | |
2065 | if (stat(cmd, &st) < 0) { | |
2066 | error("subsystem: cannot stat %s: %s", cmd, | |
2067 | strerror(errno)); | |
2068 | break; | |
2069 | } | |
2070 | debug("subsystem: exec() %s", cmd); | |
2071 | s->is_subsystem = 1; | |
2072 | do_exec(s, cmd); | |
2073 | success = 1; | |
e9702f7d | 2074 | break; |
3c0ef626 | 2075 | } |
2076 | } | |
2077 | ||
2078 | if (!success) | |
7cac2b65 | 2079 | logit("subsystem request for %.100s failed, subsystem not found", |
3c0ef626 | 2080 | subsys); |
2081 | ||
2082 | xfree(subsys); | |
2083 | return success; | |
2084 | } | |
2085 | ||
2086 | static int | |
2087 | session_x11_req(Session *s) | |
2088 | { | |
2089 | int success; | |
2090 | ||
2ce0bfe4 | 2091 | if (s->auth_proto != NULL || s->auth_data != NULL) { |
2092 | error("session_x11_req: session %d: " | |
2093 | "x11 fowarding already active", s->self); | |
2094 | return 0; | |
2095 | } | |
3c0ef626 | 2096 | s->single_connection = packet_get_char(); |
2097 | s->auth_proto = packet_get_string(NULL); | |
2098 | s->auth_data = packet_get_string(NULL); | |
2099 | s->screen = packet_get_int(); | |
e9702f7d | 2100 | packet_check_eom(); |
3c0ef626 | 2101 | |
2102 | success = session_setup_x11fwd(s); | |
2103 | if (!success) { | |
2104 | xfree(s->auth_proto); | |
2105 | xfree(s->auth_data); | |
2106 | s->auth_proto = NULL; | |
2107 | s->auth_data = NULL; | |
2108 | } | |
2109 | return success; | |
2110 | } | |
2111 | ||
2112 | static int | |
2113 | session_shell_req(Session *s) | |
2114 | { | |
e9702f7d | 2115 | packet_check_eom(); |
3c0ef626 | 2116 | do_exec(s, NULL); |
2117 | return 1; | |
2118 | } | |
2119 | ||
2120 | static int | |
2121 | session_exec_req(Session *s) | |
2122 | { | |
2123 | u_int len; | |
2124 | char *command = packet_get_string(&len); | |
e9702f7d | 2125 | packet_check_eom(); |
3c0ef626 | 2126 | do_exec(s, command); |
2127 | xfree(command); | |
2128 | return 1; | |
2129 | } | |
2130 | ||
7cac2b65 | 2131 | static int |
2132 | session_break_req(Session *s) | |
2133 | { | |
7cac2b65 | 2134 | |
7e82606e | 2135 | packet_get_int(); /* ignored */ |
7cac2b65 | 2136 | packet_check_eom(); |
2137 | ||
2138 | if (s->ttyfd == -1 || | |
2139 | tcsendbreak(s->ttyfd, 0) < 0) | |
2140 | return 0; | |
2141 | return 1; | |
2142 | } | |
2143 | ||
7e82606e | 2144 | static int |
2145 | session_env_req(Session *s) | |
2146 | { | |
2147 | char *name, *val; | |
2148 | u_int name_len, val_len, i; | |
2149 | ||
2150 | name = packet_get_string(&name_len); | |
2151 | val = packet_get_string(&val_len); | |
2152 | packet_check_eom(); | |
2153 | ||
2154 | /* Don't set too many environment variables */ | |
2155 | if (s->num_env > 128) { | |
2156 | debug2("Ignoring env request %s: too many env vars", name); | |
2157 | goto fail; | |
2158 | } | |
2159 | ||
2160 | for (i = 0; i < options.num_accept_env; i++) { | |
2161 | if (match_pattern(name, options.accept_env[i])) { | |
2162 | debug2("Setting env %d: %s=%s", s->num_env, name, val); | |
2163 | s->env = xrealloc(s->env, sizeof(*s->env) * | |
2164 | (s->num_env + 1)); | |
2165 | s->env[s->num_env].name = name; | |
2166 | s->env[s->num_env].val = val; | |
2167 | s->num_env++; | |
2168 | return (1); | |
2169 | } | |
2170 | } | |
2171 | debug2("Ignoring env request %s: disallowed name", name); | |
2172 | ||
2173 | fail: | |
2174 | xfree(name); | |
2175 | xfree(val); | |
2176 | return (0); | |
2177 | } | |
2178 | ||
3c0ef626 | 2179 | static int |
2180 | session_auth_agent_req(Session *s) | |
2181 | { | |
2182 | static int called = 0; | |
e9702f7d | 2183 | packet_check_eom(); |
3c0ef626 | 2184 | if (no_agent_forwarding_flag) { |
2185 | debug("session_auth_agent_req: no_agent_forwarding_flag"); | |
2186 | return 0; | |
2187 | } | |
2188 | if (called) { | |
2189 | return 0; | |
2190 | } else { | |
2191 | called = 1; | |
2192 | return auth_input_request_forwarding(s->pw); | |
2193 | } | |
2194 | } | |
2195 | ||
e9702f7d | 2196 | int |
2197 | session_input_channel_req(Channel *c, const char *rtype) | |
3c0ef626 | 2198 | { |
3c0ef626 | 2199 | int success = 0; |
3c0ef626 | 2200 | Session *s; |
3c0ef626 | 2201 | |
e9702f7d | 2202 | if ((s = session_by_channel(c->self)) == NULL) { |
7cac2b65 | 2203 | logit("session_input_channel_req: no session %d req %.100s", |
e9702f7d | 2204 | c->self, rtype); |
2205 | return 0; | |
2206 | } | |
2207 | debug("session_input_channel_req: session %d req %s", s->self, rtype); | |
3c0ef626 | 2208 | |
2209 | /* | |
2210 | * a session is in LARVAL state until a shell, a command | |
2211 | * or a subsystem is executed | |
2212 | */ | |
2213 | if (c->type == SSH_CHANNEL_LARVAL) { | |
2214 | if (strcmp(rtype, "shell") == 0) { | |
2215 | success = session_shell_req(s); | |
2216 | } else if (strcmp(rtype, "exec") == 0) { | |
2217 | success = session_exec_req(s); | |
2218 | } else if (strcmp(rtype, "pty-req") == 0) { | |
2219 | success = session_pty_req(s); | |
2220 | } else if (strcmp(rtype, "x11-req") == 0) { | |
2221 | success = session_x11_req(s); | |
2222 | } else if (strcmp(rtype, "auth-agent-req@openssh.com") == 0) { | |
2223 | success = session_auth_agent_req(s); | |
2224 | } else if (strcmp(rtype, "subsystem") == 0) { | |
2225 | success = session_subsystem_req(s); | |
7e82606e | 2226 | } else if (strcmp(rtype, "env") == 0) { |
2227 | success = session_env_req(s); | |
3c0ef626 | 2228 | } |
2229 | } | |
2230 | if (strcmp(rtype, "window-change") == 0) { | |
2231 | success = session_window_change_req(s); | |
7e82606e | 2232 | } else if (strcmp(rtype, "break") == 0) { |
2233 | success = session_break_req(s); | |
3c0ef626 | 2234 | } |
7e82606e | 2235 | |
e9702f7d | 2236 | return success; |
3c0ef626 | 2237 | } |
2238 | ||
2239 | void | |
2240 | session_set_fds(Session *s, int fdin, int fdout, int fderr) | |
2241 | { | |
2242 | if (!compat20) | |
2243 | fatal("session_set_fds: called for proto != 2.0"); | |
2244 | /* | |
2245 | * now that have a child and a pipe to the child, | |
2246 | * we can activate our channel and register the fd's | |
2247 | */ | |
2248 | if (s->chanid == -1) | |
2249 | fatal("no channel for session %d", s->self); | |
2250 | channel_set_fds(s->chanid, | |
2251 | fdout, fdin, fderr, | |
2252 | fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ, | |
e9702f7d | 2253 | 1, |
2254 | CHAN_SES_WINDOW_DEFAULT); | |
3c0ef626 | 2255 | } |
2256 | ||
2257 | /* | |
2258 | * Function to perform pty cleanup. Also called if we get aborted abnormally | |
2259 | * (e.g., due to a dropped connection). | |
2260 | */ | |
350391c5 | 2261 | void |
540d72c3 | 2262 | session_pty_cleanup2(Session *s) |
3c0ef626 | 2263 | { |
3c0ef626 | 2264 | if (s == NULL) { |
2265 | error("session_pty_cleanup: no session"); | |
2266 | return; | |
2267 | } | |
2268 | if (s->ttyfd == -1) | |
2269 | return; | |
2270 | ||
2271 | debug("session_pty_cleanup: session %d release %s", s->self, s->tty); | |
2272 | ||
2273 | /* Record that the user has logged out. */ | |
2274 | if (s->pid != 0) | |
e9702f7d | 2275 | record_logout(s->pid, s->tty, s->pw->pw_name); |
3c0ef626 | 2276 | |
2277 | /* Release the pseudo-tty. */ | |
350391c5 | 2278 | if (getuid() == 0) |
2279 | pty_release(s->tty); | |
3c0ef626 | 2280 | |
2281 | /* | |
2282 | * Close the server side of the socket pairs. We must do this after | |
2283 | * the pty cleanup, so that another process doesn't get this pty | |
2284 | * while we're still cleaning up. | |
2285 | */ | |
2286 | if (close(s->ptymaster) < 0) | |
350391c5 | 2287 | error("close(s->ptymaster/%d): %s", s->ptymaster, strerror(errno)); |
3c0ef626 | 2288 | |
2289 | /* unlink pty from session */ | |
2290 | s->ttyfd = -1; | |
2291 | } | |
2292 | ||
350391c5 | 2293 | void |
540d72c3 | 2294 | session_pty_cleanup(Session *s) |
350391c5 | 2295 | { |
540d72c3 | 2296 | PRIVSEP(session_pty_cleanup2(s)); |
350391c5 | 2297 | } |
2298 | ||
d03f4262 | 2299 | static char * |
2300 | sig2name(int sig) | |
2301 | { | |
2302 | #define SSH_SIG(x) if (sig == SIG ## x) return #x | |
2303 | SSH_SIG(ABRT); | |
2304 | SSH_SIG(ALRM); | |
2305 | SSH_SIG(FPE); | |
2306 | SSH_SIG(HUP); | |
2307 | SSH_SIG(ILL); | |
2308 | SSH_SIG(INT); | |
2309 | SSH_SIG(KILL); | |
2310 | SSH_SIG(PIPE); | |
2311 | SSH_SIG(QUIT); | |
2312 | SSH_SIG(SEGV); | |
2313 | SSH_SIG(TERM); | |
2314 | SSH_SIG(USR1); | |
2315 | SSH_SIG(USR2); | |
2316 | #undef SSH_SIG | |
2317 | return "SIG@openssh.com"; | |
2318 | } | |
2319 | ||
2ce0bfe4 | 2320 | static void |
2321 | session_close_x11(int id) | |
2322 | { | |
2323 | Channel *c; | |
2324 | ||
2325 | if ((c = channel_lookup(id)) == NULL) { | |
2326 | debug("session_close_x11: x11 channel %d missing", id); | |
2327 | } else { | |
2328 | /* Detach X11 listener */ | |
2329 | debug("session_close_x11: detach x11 channel %d", id); | |
2330 | channel_cancel_cleanup(id); | |
2331 | if (c->ostate != CHAN_OUTPUT_CLOSED) | |
2332 | chan_mark_dead(c); | |
2333 | } | |
2334 | } | |
2335 | ||
2336 | static void | |
2337 | session_close_single_x11(int id, void *arg) | |
2338 | { | |
2339 | Session *s; | |
2340 | u_int i; | |
2341 | ||
2342 | debug3("session_close_single_x11: channel %d", id); | |
2343 | channel_cancel_cleanup(id); | |
2344 | if ((s = session_by_x11_channel(id)) == NULL) | |
2345 | fatal("session_close_single_x11: no x11 channel %d", id); | |
2346 | for (i = 0; s->x11_chanids[i] != -1; i++) { | |
2347 | debug("session_close_single_x11: session %d: " | |
2348 | "closing channel %d", s->self, s->x11_chanids[i]); | |
2349 | /* | |
2350 | * The channel "id" is already closing, but make sure we | |
2351 | * close all of its siblings. | |
2352 | */ | |
2353 | if (s->x11_chanids[i] != id) | |
2354 | session_close_x11(s->x11_chanids[i]); | |
2355 | } | |
2356 | xfree(s->x11_chanids); | |
2357 | s->x11_chanids = NULL; | |
2358 | if (s->display) { | |
2359 | xfree(s->display); | |
2360 | s->display = NULL; | |
2361 | } | |
2362 | if (s->auth_proto) { | |
2363 | xfree(s->auth_proto); | |
2364 | s->auth_proto = NULL; | |
2365 | } | |
2366 | if (s->auth_data) { | |
2367 | xfree(s->auth_data); | |
2368 | s->auth_data = NULL; | |
2369 | } | |
2370 | if (s->auth_display) { | |
2371 | xfree(s->auth_display); | |
2372 | s->auth_display = NULL; | |
2373 | } | |
2374 | } | |
2375 | ||
3c0ef626 | 2376 | static void |
2377 | session_exit_message(Session *s, int status) | |
2378 | { | |
2379 | Channel *c; | |
2ce0bfe4 | 2380 | u_int i; |
e9702f7d | 2381 | |
2382 | if ((c = channel_lookup(s->chanid)) == NULL) | |
3c0ef626 | 2383 | fatal("session_exit_message: session %d: no channel %d", |
2384 | s->self, s->chanid); | |
44a053a3 | 2385 | debug("session_exit_message: session %d channel %d pid %ld", |
2386 | s->self, s->chanid, (long)s->pid); | |
3c0ef626 | 2387 | |
2388 | if (WIFEXITED(status)) { | |
e9702f7d | 2389 | channel_request_start(s->chanid, "exit-status", 0); |
3c0ef626 | 2390 | packet_put_int(WEXITSTATUS(status)); |
2391 | packet_send(); | |
2392 | } else if (WIFSIGNALED(status)) { | |
e9702f7d | 2393 | channel_request_start(s->chanid, "exit-signal", 0); |
d03f4262 | 2394 | packet_put_cstring(sig2name(WTERMSIG(status))); |
3c0ef626 | 2395 | #ifdef WCOREDUMP |
2396 | packet_put_char(WCOREDUMP(status)); | |
2397 | #else /* WCOREDUMP */ | |
2398 | packet_put_char(0); | |
2399 | #endif /* WCOREDUMP */ | |
2400 | packet_put_cstring(""); | |
2401 | packet_put_cstring(""); | |
2402 | packet_send(); | |
2403 | } else { | |
2404 | /* Some weird exit cause. Just exit. */ | |
2405 | packet_disconnect("wait returned status %04x.", status); | |
2406 | } | |
2407 | ||
2408 | /* disconnect channel */ | |
2409 | debug("session_exit_message: release channel %d", s->chanid); | |
2410 | channel_cancel_cleanup(s->chanid); | |
2411 | /* | |
2412 | * emulate a write failure with 'chan_write_failed', nobody will be | |
2413 | * interested in data we write. | |
2414 | * Note that we must not call 'chan_read_failed', since there could | |
2415 | * be some more data waiting in the pipe. | |
2416 | */ | |
2417 | if (c->ostate != CHAN_OUTPUT_CLOSED) | |
2418 | chan_write_failed(c); | |
2419 | s->chanid = -1; | |
2ce0bfe4 | 2420 | |
2421 | /* Close any X11 listeners associated with this session */ | |
2422 | if (s->x11_chanids != NULL) { | |
2423 | for (i = 0; s->x11_chanids[i] != -1; i++) { | |
2424 | session_close_x11(s->x11_chanids[i]); | |
2425 | s->x11_chanids[i] = -1; | |
2426 | } | |
2427 | } | |
3c0ef626 | 2428 | } |
2429 | ||
350391c5 | 2430 | void |
3c0ef626 | 2431 | session_close(Session *s) |
2432 | { | |
2ce0bfe4 | 2433 | u_int i; |
7e82606e | 2434 | |
44a053a3 | 2435 | debug("session_close: session %d pid %ld", s->self, (long)s->pid); |
540d72c3 | 2436 | if (s->ttyfd != -1) |
3c0ef626 | 2437 | session_pty_cleanup(s); |
3c0ef626 | 2438 | if (s->term) |
2439 | xfree(s->term); | |
2440 | if (s->display) | |
2441 | xfree(s->display); | |
2ce0bfe4 | 2442 | if (s->x11_chanids) |
2443 | xfree(s->x11_chanids); | |
e9702f7d | 2444 | if (s->auth_display) |
2445 | xfree(s->auth_display); | |
3c0ef626 | 2446 | if (s->auth_data) |
2447 | xfree(s->auth_data); | |
2448 | if (s->auth_proto) | |
2449 | xfree(s->auth_proto); | |
2450 | s->used = 0; | |
7e82606e | 2451 | for (i = 0; i < s->num_env; i++) { |
2452 | xfree(s->env[i].name); | |
2453 | xfree(s->env[i].val); | |
2454 | } | |
2455 | if (s->env != NULL) | |
2456 | xfree(s->env); | |
3c0ef626 | 2457 | session_proctitle(s); |
2458 | } | |
2459 | ||
2460 | void | |
2461 | session_close_by_pid(pid_t pid, int status) | |
2462 | { | |
2463 | Session *s = session_by_pid(pid); | |
2464 | if (s == NULL) { | |
44a053a3 | 2465 | debug("session_close_by_pid: no session for pid %ld", |
2466 | (long)pid); | |
3c0ef626 | 2467 | return; |
2468 | } | |
2469 | if (s->chanid != -1) | |
2470 | session_exit_message(s, status); | |
2471 | session_close(s); | |
2472 | } | |
2473 | ||
2474 | /* | |
2475 | * this is called when a channel dies before | |
2476 | * the session 'child' itself dies | |
2477 | */ | |
2478 | void | |
2479 | session_close_by_channel(int id, void *arg) | |
2480 | { | |
2481 | Session *s = session_by_channel(id); | |
2ce0bfe4 | 2482 | |
3c0ef626 | 2483 | if (s == NULL) { |
2484 | debug("session_close_by_channel: no session for id %d", id); | |
2485 | return; | |
2486 | } | |
44a053a3 | 2487 | debug("session_close_by_channel: channel %d child %ld", |
2488 | id, (long)s->pid); | |
3c0ef626 | 2489 | if (s->pid != 0) { |
2490 | debug("session_close_by_channel: channel %d: has child", id); | |
2491 | /* | |
2492 | * delay detach of session, but release pty, since | |
2493 | * the fd's to the child are already closed | |
2494 | */ | |
540d72c3 | 2495 | if (s->ttyfd != -1) |
3c0ef626 | 2496 | session_pty_cleanup(s); |
3c0ef626 | 2497 | return; |
2498 | } | |
2499 | /* detach by removing callback */ | |
2500 | channel_cancel_cleanup(s->chanid); | |
2501 | s->chanid = -1; | |
2502 | session_close(s); | |
2503 | } | |
2504 | ||
2505 | void | |
350391c5 | 2506 | session_destroy_all(void (*closefunc)(Session *)) |
3c0ef626 | 2507 | { |
2508 | int i; | |
e9702f7d | 2509 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 2510 | Session *s = &sessions[i]; |
350391c5 | 2511 | if (s->used) { |
2512 | if (closefunc != NULL) | |
2513 | closefunc(s); | |
2514 | else | |
2515 | session_close(s); | |
2516 | } | |
3c0ef626 | 2517 | } |
2518 | } | |
2519 | ||
2520 | static char * | |
2521 | session_tty_list(void) | |
2522 | { | |
2523 | static char buf[1024]; | |
2524 | int i; | |
bfe49944 | 2525 | char *cp; |
2526 | ||
3c0ef626 | 2527 | buf[0] = '\0'; |
e9702f7d | 2528 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 2529 | Session *s = &sessions[i]; |
2530 | if (s->used && s->ttyfd != -1) { | |
540d72c3 | 2531 | |
bfe49944 | 2532 | if (strncmp(s->tty, "/dev/", 5) != 0) { |
2533 | cp = strrchr(s->tty, '/'); | |
2534 | cp = (cp == NULL) ? s->tty : cp + 1; | |
2535 | } else | |
2536 | cp = s->tty + 5; | |
540d72c3 | 2537 | |
3c0ef626 | 2538 | if (buf[0] != '\0') |
2539 | strlcat(buf, ",", sizeof buf); | |
bfe49944 | 2540 | strlcat(buf, cp, sizeof buf); |
3c0ef626 | 2541 | } |
2542 | } | |
2543 | if (buf[0] == '\0') | |
2544 | strlcpy(buf, "notty", sizeof buf); | |
2545 | return buf; | |
2546 | } | |
2547 | ||
2548 | void | |
2549 | session_proctitle(Session *s) | |
2550 | { | |
2551 | if (s->pw == NULL) | |
2552 | error("no user for session %d", s->self); | |
2553 | else | |
2554 | setproctitle("%s@%s", s->pw->pw_name, session_tty_list()); | |
2555 | } | |
2556 | ||
2557 | int | |
2558 | session_setup_x11fwd(Session *s) | |
2559 | { | |
2560 | struct stat st; | |
e9702f7d | 2561 | char display[512], auth_display[512]; |
2562 | char hostname[MAXHOSTNAMELEN]; | |
2ce0bfe4 | 2563 | u_int i; |
3c0ef626 | 2564 | |
2565 | if (no_x11_forwarding_flag) { | |
2566 | packet_send_debug("X11 forwarding disabled in user configuration file."); | |
2567 | return 0; | |
2568 | } | |
2569 | if (!options.x11_forwarding) { | |
2570 | debug("X11 forwarding disabled in server configuration file."); | |
2571 | return 0; | |
2572 | } | |
2573 | if (!options.xauth_location || | |
2574 | (stat(options.xauth_location, &st) == -1)) { | |
2575 | packet_send_debug("No xauth program; cannot forward with spoofing."); | |
2576 | return 0; | |
2577 | } | |
2578 | if (options.use_login) { | |
2579 | packet_send_debug("X11 forwarding disabled; " | |
2580 | "not compatible with UseLogin=yes."); | |
2581 | return 0; | |
2582 | } | |
2583 | if (s->display != NULL) { | |
2584 | debug("X11 display already set."); | |
2585 | return 0; | |
2586 | } | |
276b07a3 | 2587 | if (x11_create_display_inet(options.x11_display_offset, |
2588 | options.x11_use_localhost, s->single_connection, | |
2ce0bfe4 | 2589 | &s->display_number, &s->x11_chanids) == -1) { |
3c0ef626 | 2590 | debug("x11_create_display_inet failed."); |
2591 | return 0; | |
2592 | } | |
2ce0bfe4 | 2593 | for (i = 0; s->x11_chanids[i] != -1; i++) { |
2594 | channel_register_cleanup(s->x11_chanids[i], | |
2595 | session_close_single_x11); | |
2596 | } | |
e9702f7d | 2597 | |
2598 | /* Set up a suitable value for the DISPLAY variable. */ | |
2599 | if (gethostname(hostname, sizeof(hostname)) < 0) | |
2600 | fatal("gethostname: %.100s", strerror(errno)); | |
2601 | /* | |
2602 | * auth_display must be used as the displayname when the | |
2603 | * authorization entry is added with xauth(1). This will be | |
2604 | * different than the DISPLAY string for localhost displays. | |
2605 | */ | |
2606 | if (options.x11_use_localhost) { | |
276b07a3 | 2607 | snprintf(display, sizeof display, "localhost:%u.%u", |
e9702f7d | 2608 | s->display_number, s->screen); |
276b07a3 | 2609 | snprintf(auth_display, sizeof auth_display, "unix:%u.%u", |
e9702f7d | 2610 | s->display_number, s->screen); |
2611 | s->display = xstrdup(display); | |
2612 | s->auth_display = xstrdup(auth_display); | |
2613 | } else { | |
2614 | #ifdef IPADDR_IN_DISPLAY | |
2615 | struct hostent *he; | |
2616 | struct in_addr my_addr; | |
2617 | ||
2618 | he = gethostbyname(hostname); | |
2619 | if (he == NULL) { | |
2620 | error("Can't get IP address for X11 DISPLAY."); | |
2621 | packet_send_debug("Can't get IP address for X11 DISPLAY."); | |
2622 | return 0; | |
2623 | } | |
2624 | memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr)); | |
276b07a3 | 2625 | snprintf(display, sizeof display, "%.50s:%u.%u", inet_ntoa(my_addr), |
e9702f7d | 2626 | s->display_number, s->screen); |
2627 | #else | |
276b07a3 | 2628 | snprintf(display, sizeof display, "%.400s:%u.%u", hostname, |
e9702f7d | 2629 | s->display_number, s->screen); |
2630 | #endif | |
2631 | s->display = xstrdup(display); | |
2632 | s->auth_display = xstrdup(display); | |
2633 | } | |
2634 | ||
3c0ef626 | 2635 | return 1; |
2636 | } | |
2637 | ||
2638 | static void | |
2639 | do_authenticated2(Authctxt *authctxt) | |
2640 | { | |
2641 | server_loop2(authctxt); | |
540d72c3 | 2642 | } |
2643 | ||
2644 | void | |
2645 | do_cleanup(Authctxt *authctxt) | |
2646 | { | |
2647 | static int called = 0; | |
2648 | ||
2649 | debug("do_cleanup"); | |
2650 | ||
2651 | /* no cleanup if we're in the child for login shell */ | |
2652 | if (is_child) | |
2653 | return; | |
2654 | ||
2655 | /* avoid double cleanup */ | |
2656 | if (called) | |
2657 | return; | |
2658 | called = 1; | |
2659 | ||
2660 | if (authctxt == NULL) | |
2661 | return; | |
2662 | #ifdef KRB5 | |
2663 | if (options.kerberos_ticket_cleanup && | |
2664 | authctxt->krb5_ctx) | |
2665 | krb5_cleanup_proc(authctxt); | |
5598e598 | 2666 | #endif |
540d72c3 | 2667 | |
2668 | #ifdef GSSAPI | |
2669 | if (compat20 && options.gss_cleanup_creds) | |
2670 | ssh_gssapi_cleanup_creds(); | |
2671 | #endif | |
2672 | ||
2673 | #ifdef USE_PAM | |
2674 | if (options.use_pam) { | |
2675 | sshpam_cleanup(); | |
2676 | sshpam_thread_cleanup(); | |
2677 | } | |
2678 | #endif | |
2679 | ||
2680 | /* remove agent socket */ | |
2681 | auth_sock_cleanup_proc(authctxt->pw); | |
2682 | ||
2683 | /* | |
2684 | * Cleanup ptys/utmp only if privsep is disabled, | |
2685 | * or if running in monitor. | |
2686 | */ | |
2687 | if (!use_privsep || mm_is_monitor()) | |
2688 | session_destroy_all(session_pty_cleanup2); | |
3c0ef626 | 2689 | } |