]>
Commit | Line | Data |
---|---|---|
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" | |
08822d99 | 36 | RCSID("$OpenBSD: session.c,v 1.191 2005/12/24 02:27:41 djm 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. */ | |
a7213e65 | 194 | /* this shouldn't matter if its hpn or not - cjr */ |
44a053a3 | 195 | nc = channel_new("auth socket", |
196 | SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1, | |
197 | CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, | |
7cac2b65 | 198 | 0, "auth socket", 1); |
44a053a3 | 199 | strlcpy(nc->path, auth_sock_name, sizeof(nc->path)); |
200 | return 1; | |
201 | } | |
202 | ||
540d72c3 | 203 | static void |
204 | display_loginmsg(void) | |
205 | { | |
2ce0bfe4 | 206 | if (buffer_len(&loginmsg) > 0) { |
207 | buffer_append(&loginmsg, "\0", 1); | |
208 | printf("%s", (char *)buffer_ptr(&loginmsg)); | |
209 | buffer_clear(&loginmsg); | |
210 | } | |
540d72c3 | 211 | } |
44a053a3 | 212 | |
3c0ef626 | 213 | void |
214 | do_authenticated(Authctxt *authctxt) | |
215 | { | |
bfe49944 | 216 | setproctitle("%s", authctxt->pw->pw_name); |
217 | ||
3c0ef626 | 218 | /* setup the channel layer */ |
219 | if (!no_port_forwarding_flag && options.allow_tcp_forwarding) | |
220 | channel_permit_all_opens(); | |
221 | ||
222 | if (compat20) | |
223 | do_authenticated2(authctxt); | |
224 | else | |
225 | do_authenticated1(authctxt); | |
226 | ||
75be3237 | 227 | #ifdef SESSION_HOOKS |
228 | if (options.session_hooks_allow && | |
229 | options.session_hooks_shutdown_cmd) | |
230 | { | |
231 | execute_session_hook(options.session_hooks_shutdown_cmd, | |
232 | authctxt, | |
233 | /* startup = */ 0, /* save = */ 0); | |
234 | ||
235 | if (authctxt->session_env_file) | |
236 | { | |
237 | free(authctxt->session_env_file); | |
238 | } | |
239 | } | |
240 | #endif | |
540d72c3 | 241 | |
242 | do_cleanup(authctxt); | |
3c0ef626 | 243 | } |
244 | ||
245 | /* | |
246 | * Prepares for an interactive session. This is called after the user has | |
247 | * been successfully authenticated. During this message exchange, pseudo | |
248 | * terminals are allocated, X11, TCP/IP, and authentication agent forwardings | |
249 | * are requested, etc. | |
250 | */ | |
251 | static void | |
252 | do_authenticated1(Authctxt *authctxt) | |
253 | { | |
254 | Session *s; | |
255 | char *command; | |
e9702f7d | 256 | int success, type, screen_flag; |
276b07a3 | 257 | int enable_compression_after_reply = 0; |
258 | u_int proto_len, data_len, dlen, compression_level = 0; | |
3c0ef626 | 259 | |
260 | s = session_new(); | |
dfddba3d | 261 | if (s == NULL) { |
262 | error("no more sessions"); | |
263 | return; | |
264 | } | |
3c0ef626 | 265 | s->authctxt = authctxt; |
266 | s->pw = authctxt->pw; | |
267 | ||
268 | /* | |
269 | * We stay in this loop until the client requests to execute a shell | |
270 | * or a command. | |
271 | */ | |
272 | for (;;) { | |
273 | success = 0; | |
274 | ||
275 | /* Get a packet from the client. */ | |
e9702f7d | 276 | type = packet_read(); |
3c0ef626 | 277 | |
278 | /* Process the packet. */ | |
279 | switch (type) { | |
280 | case SSH_CMSG_REQUEST_COMPRESSION: | |
3c0ef626 | 281 | compression_level = packet_get_int(); |
e9702f7d | 282 | packet_check_eom(); |
3c0ef626 | 283 | if (compression_level < 1 || compression_level > 9) { |
7e82606e | 284 | packet_send_debug("Received invalid compression level %d.", |
e9702f7d | 285 | compression_level); |
3c0ef626 | 286 | break; |
287 | } | |
2ce0bfe4 | 288 | if (options.compression == COMP_NONE) { |
44a053a3 | 289 | debug2("compression disabled"); |
290 | break; | |
291 | } | |
3c0ef626 | 292 | /* Enable compression after we have responded with SUCCESS. */ |
293 | enable_compression_after_reply = 1; | |
294 | success = 1; | |
295 | break; | |
296 | ||
297 | case SSH_CMSG_REQUEST_PTY: | |
298 | success = session_pty_req(s); | |
299 | break; | |
300 | ||
301 | case SSH_CMSG_X11_REQUEST_FORWARDING: | |
302 | s->auth_proto = packet_get_string(&proto_len); | |
303 | s->auth_data = packet_get_string(&data_len); | |
304 | ||
305 | screen_flag = packet_get_protocol_flags() & | |
306 | SSH_PROTOFLAG_SCREEN_NUMBER; | |
307 | debug2("SSH_PROTOFLAG_SCREEN_NUMBER: %d", screen_flag); | |
308 | ||
309 | if (packet_remaining() == 4) { | |
310 | if (!screen_flag) | |
311 | debug2("Buggy client: " | |
312 | "X11 screen flag missing"); | |
313 | s->screen = packet_get_int(); | |
314 | } else { | |
315 | s->screen = 0; | |
316 | } | |
e9702f7d | 317 | packet_check_eom(); |
3c0ef626 | 318 | success = session_setup_x11fwd(s); |
319 | if (!success) { | |
320 | xfree(s->auth_proto); | |
321 | xfree(s->auth_data); | |
322 | s->auth_proto = NULL; | |
323 | s->auth_data = NULL; | |
324 | } | |
325 | break; | |
326 | ||
327 | case SSH_CMSG_AGENT_REQUEST_FORWARDING: | |
328 | if (no_agent_forwarding_flag || compat13) { | |
329 | debug("Authentication agent forwarding not permitted for this authentication."); | |
330 | break; | |
331 | } | |
332 | debug("Received authentication agent forwarding request."); | |
333 | success = auth_input_request_forwarding(s->pw); | |
334 | break; | |
335 | ||
336 | case SSH_CMSG_PORT_FORWARD_REQUEST: | |
337 | if (no_port_forwarding_flag) { | |
338 | debug("Port forwarding not permitted for this authentication."); | |
339 | break; | |
340 | } | |
341 | if (!options.allow_tcp_forwarding) { | |
342 | debug("Port forwarding not permitted."); | |
343 | break; | |
344 | } | |
345 | debug("Received TCP/IP port forwarding request."); | |
a7213e65 | 346 | channel_input_port_forward_request(s->pw->pw_uid == 0, options.gateway_ports, |
347 | options.hpn_disabled, | |
348 | options.hpn_buffer_size); | |
3c0ef626 | 349 | success = 1; |
350 | break; | |
351 | ||
352 | case SSH_CMSG_MAX_PACKET_SIZE: | |
353 | if (packet_set_maxsize(packet_get_int()) > 0) | |
354 | success = 1; | |
355 | break; | |
e9702f7d | 356 | |
3c0ef626 | 357 | case SSH_CMSG_EXEC_SHELL: |
358 | case SSH_CMSG_EXEC_CMD: | |
359 | if (type == SSH_CMSG_EXEC_CMD) { | |
360 | command = packet_get_string(&dlen); | |
361 | debug("Exec command '%.500s'", command); | |
362 | do_exec(s, command); | |
363 | xfree(command); | |
364 | } else { | |
365 | do_exec(s, NULL); | |
366 | } | |
e9702f7d | 367 | packet_check_eom(); |
3c0ef626 | 368 | session_close(s); |
369 | return; | |
370 | ||
371 | default: | |
372 | /* | |
373 | * Any unknown messages in this phase are ignored, | |
374 | * and a failure message is returned. | |
375 | */ | |
7cac2b65 | 376 | logit("Unknown packet type received after authentication: %d", type); |
3c0ef626 | 377 | } |
378 | packet_start(success ? SSH_SMSG_SUCCESS : SSH_SMSG_FAILURE); | |
379 | packet_send(); | |
380 | packet_write_wait(); | |
381 | ||
382 | /* Enable compression now that we have replied if appropriate. */ | |
383 | if (enable_compression_after_reply) { | |
384 | enable_compression_after_reply = 0; | |
385 | packet_start_compression(compression_level); | |
386 | } | |
387 | } | |
388 | } | |
389 | ||
390 | /* | |
391 | * This is called to fork and execute a command when we have no tty. This | |
392 | * will call do_child from the child, and server_loop from the parent after | |
393 | * setting up file descriptors and such. | |
394 | */ | |
395 | void | |
396 | do_exec_no_pty(Session *s, const char *command) | |
397 | { | |
44a053a3 | 398 | pid_t pid; |
3c0ef626 | 399 | |
400 | #ifdef USE_PIPES | |
401 | int pin[2], pout[2], perr[2]; | |
402 | /* Allocate pipes for communicating with the program. */ | |
403 | if (pipe(pin) < 0 || pipe(pout) < 0 || pipe(perr) < 0) | |
404 | packet_disconnect("Could not create pipes: %.100s", | |
405 | strerror(errno)); | |
406 | #else /* USE_PIPES */ | |
407 | int inout[2], err[2]; | |
408 | /* Uses socket pairs to communicate with the program. */ | |
409 | if (socketpair(AF_UNIX, SOCK_STREAM, 0, inout) < 0 || | |
410 | socketpair(AF_UNIX, SOCK_STREAM, 0, err) < 0) | |
411 | packet_disconnect("Could not create socket pairs: %.100s", | |
412 | strerror(errno)); | |
413 | #endif /* USE_PIPES */ | |
414 | if (s == NULL) | |
415 | fatal("do_exec_no_pty: no session"); | |
416 | ||
417 | session_proctitle(s); | |
418 | ||
419 | #if defined(USE_PAM) | |
540d72c3 | 420 | if (options.use_pam && !use_privsep) |
7cac2b65 | 421 | do_pam_setcred(1); |
3c0ef626 | 422 | #endif /* USE_PAM */ |
423 | ||
424 | /* Fork the child. */ | |
425 | if ((pid = fork()) == 0) { | |
540d72c3 | 426 | is_child = 1; |
d03f4262 | 427 | |
3c0ef626 | 428 | /* Child. Reinitialize the log since the pid has changed. */ |
429 | log_init(__progname, options.log_level, options.log_facility, log_stderr); | |
430 | ||
431 | /* | |
432 | * Create a new session and process group since the 4.4BSD | |
433 | * setlogin() affects the entire process group. | |
434 | */ | |
435 | if (setsid() < 0) | |
436 | error("setsid failed: %.100s", strerror(errno)); | |
437 | ||
438 | #ifdef USE_PIPES | |
439 | /* | |
440 | * Redirect stdin. We close the parent side of the socket | |
441 | * pair, and make the child side the standard input. | |
442 | */ | |
443 | close(pin[1]); | |
444 | if (dup2(pin[0], 0) < 0) | |
445 | perror("dup2 stdin"); | |
446 | close(pin[0]); | |
447 | ||
448 | /* Redirect stdout. */ | |
449 | close(pout[0]); | |
450 | if (dup2(pout[1], 1) < 0) | |
451 | perror("dup2 stdout"); | |
452 | close(pout[1]); | |
453 | ||
454 | /* Redirect stderr. */ | |
455 | close(perr[0]); | |
456 | if (dup2(perr[1], 2) < 0) | |
457 | perror("dup2 stderr"); | |
458 | close(perr[1]); | |
459 | #else /* USE_PIPES */ | |
460 | /* | |
461 | * Redirect stdin, stdout, and stderr. Stdin and stdout will | |
462 | * use the same socket, as some programs (particularly rdist) | |
463 | * seem to depend on it. | |
464 | */ | |
465 | close(inout[1]); | |
466 | close(err[1]); | |
467 | if (dup2(inout[0], 0) < 0) /* stdin */ | |
468 | perror("dup2 stdin"); | |
469 | if (dup2(inout[0], 1) < 0) /* stdout. Note: same socket as stdin. */ | |
470 | perror("dup2 stdout"); | |
471 | if (dup2(err[0], 2) < 0) /* stderr */ | |
472 | perror("dup2 stderr"); | |
473 | #endif /* USE_PIPES */ | |
474 | ||
d03f4262 | 475 | #ifdef _UNICOS |
476 | cray_init_job(s->pw); /* set up cray jid and tmpdir */ | |
477 | #endif | |
478 | ||
3c0ef626 | 479 | /* Do processing for the child (exec command etc). */ |
480 | do_child(s, command); | |
481 | /* NOTREACHED */ | |
482 | } | |
d03f4262 | 483 | #ifdef _UNICOS |
484 | signal(WJSIGNAL, cray_job_termination_handler); | |
485 | #endif /* _UNICOS */ | |
3c0ef626 | 486 | #ifdef HAVE_CYGWIN |
487 | if (is_winnt) | |
488 | cygwin_set_impersonation_token(INVALID_HANDLE_VALUE); | |
489 | #endif | |
490 | if (pid < 0) | |
491 | packet_disconnect("fork failed: %.100s", strerror(errno)); | |
492 | s->pid = pid; | |
493 | /* Set interactive/non-interactive mode. */ | |
494 | packet_set_interactive(s->display != NULL); | |
495 | #ifdef USE_PIPES | |
496 | /* We are the parent. Close the child sides of the pipes. */ | |
497 | close(pin[0]); | |
498 | close(pout[1]); | |
499 | close(perr[1]); | |
500 | ||
501 | if (compat20) { | |
7e82606e | 502 | if (s->is_subsystem) { |
503 | close(perr[0]); | |
504 | perr[0] = -1; | |
505 | } | |
506 | session_set_fds(s, pin[1], pout[0], perr[0]); | |
3c0ef626 | 507 | } else { |
508 | /* Enter the interactive session. */ | |
509 | server_loop(pid, pin[1], pout[0], perr[0]); | |
510 | /* server_loop has closed pin[1], pout[0], and perr[0]. */ | |
511 | } | |
512 | #else /* USE_PIPES */ | |
513 | /* We are the parent. Close the child sides of the socket pairs. */ | |
514 | close(inout[0]); | |
515 | close(err[0]); | |
516 | ||
12a403af | 517 | /* |
518 | * Clear loginmsg, since it's the child's responsibility to display | |
519 | * it to the user, otherwise multiple sessions may accumulate | |
520 | * multiple copies of the login messages. | |
521 | */ | |
522 | buffer_clear(&loginmsg); | |
523 | ||
3c0ef626 | 524 | /* |
525 | * Enter the interactive session. Note: server_loop must be able to | |
526 | * handle the case that fdin and fdout are the same. | |
527 | */ | |
528 | if (compat20) { | |
529 | session_set_fds(s, inout[1], inout[1], s->is_subsystem ? -1 : err[1]); | |
530 | } else { | |
531 | server_loop(pid, inout[1], inout[1], err[1]); | |
532 | /* server_loop has closed inout[1] and err[1]. */ | |
533 | } | |
534 | #endif /* USE_PIPES */ | |
535 | } | |
536 | ||
537 | /* | |
538 | * This is called to fork and execute a command when we have a tty. This | |
539 | * will call do_child from the child, and server_loop from the parent after | |
540 | * setting up file descriptors, controlling tty, updating wtmp, utmp, | |
541 | * lastlog, and other such operations. | |
542 | */ | |
543 | void | |
544 | do_exec_pty(Session *s, const char *command) | |
545 | { | |
546 | int fdout, ptyfd, ttyfd, ptymaster; | |
547 | pid_t pid; | |
548 | ||
549 | if (s == NULL) | |
550 | fatal("do_exec_pty: no session"); | |
551 | ptyfd = s->ptyfd; | |
552 | ttyfd = s->ttyfd; | |
553 | ||
554 | #if defined(USE_PAM) | |
7cac2b65 | 555 | if (options.use_pam) { |
556 | do_pam_set_tty(s->tty); | |
540d72c3 | 557 | if (!use_privsep) |
558 | do_pam_setcred(1); | |
7cac2b65 | 559 | } |
3c0ef626 | 560 | #endif |
561 | ||
562 | /* Fork the child. */ | |
563 | if ((pid = fork()) == 0) { | |
540d72c3 | 564 | is_child = 1; |
3c0ef626 | 565 | |
566 | /* Child. Reinitialize the log because the pid has changed. */ | |
567 | log_init(__progname, options.log_level, options.log_facility, log_stderr); | |
568 | /* Close the master side of the pseudo tty. */ | |
569 | close(ptyfd); | |
570 | ||
571 | /* Make the pseudo tty our controlling tty. */ | |
572 | pty_make_controlling_tty(&ttyfd, s->tty); | |
573 | ||
574 | /* Redirect stdin/stdout/stderr from the pseudo tty. */ | |
575 | if (dup2(ttyfd, 0) < 0) | |
576 | error("dup2 stdin: %s", strerror(errno)); | |
577 | if (dup2(ttyfd, 1) < 0) | |
578 | error("dup2 stdout: %s", strerror(errno)); | |
579 | if (dup2(ttyfd, 2) < 0) | |
580 | error("dup2 stderr: %s", strerror(errno)); | |
581 | ||
582 | /* Close the extra descriptor for the pseudo tty. */ | |
583 | close(ttyfd); | |
584 | ||
585 | /* record login, etc. similar to login(1) */ | |
586 | #ifndef HAVE_OSF_SIA | |
d03f4262 | 587 | if (!(options.use_login && command == NULL)) { |
588 | #ifdef _UNICOS | |
589 | cray_init_job(s->pw); /* set up cray jid and tmpdir */ | |
590 | #endif /* _UNICOS */ | |
3c0ef626 | 591 | do_login(s, command); |
d03f4262 | 592 | } |
3c0ef626 | 593 | # ifdef LOGIN_NEEDS_UTMPX |
594 | else | |
595 | do_pre_login(s); | |
596 | # endif | |
597 | #endif | |
598 | ||
599 | /* Do common processing for the child, such as execing the command. */ | |
600 | do_child(s, command); | |
601 | /* NOTREACHED */ | |
602 | } | |
d03f4262 | 603 | #ifdef _UNICOS |
604 | signal(WJSIGNAL, cray_job_termination_handler); | |
605 | #endif /* _UNICOS */ | |
3c0ef626 | 606 | #ifdef HAVE_CYGWIN |
607 | if (is_winnt) | |
608 | cygwin_set_impersonation_token(INVALID_HANDLE_VALUE); | |
609 | #endif | |
610 | if (pid < 0) | |
611 | packet_disconnect("fork failed: %.100s", strerror(errno)); | |
612 | s->pid = pid; | |
613 | ||
614 | /* Parent. Close the slave side of the pseudo tty. */ | |
615 | close(ttyfd); | |
616 | ||
617 | /* | |
618 | * Create another descriptor of the pty master side for use as the | |
619 | * standard input. We could use the original descriptor, but this | |
620 | * simplifies code in server_loop. The descriptor is bidirectional. | |
621 | */ | |
622 | fdout = dup(ptyfd); | |
623 | if (fdout < 0) | |
624 | packet_disconnect("dup #1 failed: %.100s", strerror(errno)); | |
625 | ||
626 | /* we keep a reference to the pty master */ | |
627 | ptymaster = dup(ptyfd); | |
628 | if (ptymaster < 0) | |
629 | packet_disconnect("dup #2 failed: %.100s", strerror(errno)); | |
630 | s->ptymaster = ptymaster; | |
631 | ||
632 | /* Enter interactive session. */ | |
633 | packet_set_interactive(1); | |
634 | if (compat20) { | |
635 | session_set_fds(s, ptyfd, fdout, -1); | |
636 | } else { | |
637 | server_loop(pid, ptyfd, fdout, -1); | |
638 | /* server_loop _has_ closed ptyfd and fdout. */ | |
639 | } | |
640 | } | |
641 | ||
642 | #ifdef LOGIN_NEEDS_UTMPX | |
643 | static void | |
644 | do_pre_login(Session *s) | |
645 | { | |
646 | socklen_t fromlen; | |
647 | struct sockaddr_storage from; | |
648 | pid_t pid = getpid(); | |
649 | ||
650 | /* | |
651 | * Get IP address of client. If the connection is not a socket, let | |
652 | * the address be 0.0.0.0. | |
653 | */ | |
654 | memset(&from, 0, sizeof(from)); | |
d03f4262 | 655 | fromlen = sizeof(from); |
3c0ef626 | 656 | if (packet_connection_is_on_socket()) { |
3c0ef626 | 657 | if (getpeername(packet_get_connection_in(), |
e9702f7d | 658 | (struct sockaddr *) & from, &fromlen) < 0) { |
3c0ef626 | 659 | debug("getpeername: %.100s", strerror(errno)); |
540d72c3 | 660 | cleanup_exit(255); |
3c0ef626 | 661 | } |
662 | } | |
663 | ||
664 | record_utmp_only(pid, s->tty, s->pw->pw_name, | |
7cac2b65 | 665 | get_remote_name_or_ip(utmp_len, options.use_dns), |
bfe49944 | 666 | (struct sockaddr *)&from, fromlen); |
3c0ef626 | 667 | } |
668 | #endif | |
669 | ||
670 | /* | |
671 | * This is called to fork and execute a command. If another command is | |
672 | * to be forced, execute that instead. | |
673 | */ | |
674 | void | |
675 | do_exec(Session *s, const char *command) | |
676 | { | |
677 | if (forced_command) { | |
678 | original_command = command; | |
679 | command = forced_command; | |
680 | debug("Forced command '%.900s'", command); | |
681 | } | |
682 | ||
7cac2b65 | 683 | #if defined(SESSION_HOOKS) |
684 | if (options.session_hooks_allow && | |
685 | (options.session_hooks_startup_cmd || | |
686 | options.session_hooks_shutdown_cmd)) | |
687 | { | |
688 | char env_file[1000]; | |
689 | struct stat st; | |
690 | do | |
691 | { | |
692 | snprintf(env_file, | |
693 | sizeof(env_file), | |
694 | "/tmp/ssh_env_%d%d%d", | |
695 | getuid(), | |
696 | getpid(), | |
697 | rand()); | |
698 | } while (stat(env_file, &st)==0); | |
699 | s->authctxt->session_env_file = strdup(env_file); | |
700 | } | |
701 | #endif | |
702 | ||
dfddba3d | 703 | #ifdef SSH_AUDIT_EVENTS |
704 | if (command != NULL) | |
705 | PRIVSEP(audit_run_command(command)); | |
706 | else if (s->ttyfd == -1) { | |
707 | char *shell = s->pw->pw_shell; | |
708 | ||
709 | if (shell[0] == '\0') /* empty shell means /bin/sh */ | |
710 | shell =_PATH_BSHELL; | |
711 | PRIVSEP(audit_run_command(shell)); | |
712 | } | |
713 | #endif | |
714 | ||
3c0ef626 | 715 | if (s->ttyfd != -1) |
716 | do_exec_pty(s, command); | |
717 | else | |
718 | do_exec_no_pty(s, command); | |
719 | ||
720 | original_command = NULL; | |
3c0ef626 | 721 | |
7e82606e | 722 | /* |
723 | * Clear loginmsg: it's the child's responsibility to display | |
724 | * it to the user, otherwise multiple sessions may accumulate | |
725 | * multiple copies of the login messages. | |
726 | */ | |
727 | buffer_clear(&loginmsg); | |
728 | } | |
e9702f7d | 729 | |
3c0ef626 | 730 | /* administrative, login(1)-like work */ |
731 | void | |
732 | do_login(Session *s, const char *command) | |
733 | { | |
3c0ef626 | 734 | socklen_t fromlen; |
735 | struct sockaddr_storage from; | |
3c0ef626 | 736 | struct passwd * pw = s->pw; |
737 | pid_t pid = getpid(); | |
738 | ||
739 | /* | |
740 | * Get IP address of client. If the connection is not a socket, let | |
741 | * the address be 0.0.0.0. | |
742 | */ | |
743 | memset(&from, 0, sizeof(from)); | |
bfe49944 | 744 | fromlen = sizeof(from); |
3c0ef626 | 745 | if (packet_connection_is_on_socket()) { |
3c0ef626 | 746 | if (getpeername(packet_get_connection_in(), |
e9702f7d | 747 | (struct sockaddr *) & from, &fromlen) < 0) { |
3c0ef626 | 748 | debug("getpeername: %.100s", strerror(errno)); |
540d72c3 | 749 | cleanup_exit(255); |
3c0ef626 | 750 | } |
751 | } | |
752 | ||
3c0ef626 | 753 | /* Record that there was a login on that tty from the remote host. */ |
350391c5 | 754 | if (!use_privsep) |
755 | record_login(pid, s->tty, pw->pw_name, pw->pw_uid, | |
756 | get_remote_name_or_ip(utmp_len, | |
7cac2b65 | 757 | options.use_dns), |
d03f4262 | 758 | (struct sockaddr *)&from, fromlen); |
3c0ef626 | 759 | |
760 | #ifdef USE_PAM | |
761 | /* | |
762 | * If password change is needed, do it now. | |
763 | * This needs to occur before the ~/.hushlogin check. | |
764 | */ | |
540d72c3 | 765 | if (options.use_pam && !use_privsep && s->authctxt->force_pwchange) { |
766 | display_loginmsg(); | |
3c0ef626 | 767 | do_pam_chauthtok(); |
540d72c3 | 768 | s->authctxt->force_pwchange = 0; |
7cac2b65 | 769 | /* XXX - signal [net] parent to enable forwardings */ |
3c0ef626 | 770 | } |
771 | #endif | |
772 | ||
773 | if (check_quietlogin(s, command)) | |
774 | return; | |
775 | ||
540d72c3 | 776 | display_loginmsg(); |
3c0ef626 | 777 | |
3c0ef626 | 778 | do_motd(); |
779 | } | |
780 | ||
781 | /* | |
782 | * Display the message of the day. | |
783 | */ | |
784 | void | |
785 | do_motd(void) | |
786 | { | |
787 | FILE *f; | |
788 | char buf[256]; | |
789 | ||
790 | if (options.print_motd) { | |
791 | #ifdef HAVE_LOGIN_CAP | |
792 | f = fopen(login_getcapstr(lc, "welcome", "/etc/motd", | |
793 | "/etc/motd"), "r"); | |
794 | #else | |
795 | f = fopen("/etc/motd", "r"); | |
796 | #endif | |
797 | if (f) { | |
798 | while (fgets(buf, sizeof(buf), f)) | |
799 | fputs(buf, stdout); | |
800 | fclose(f); | |
801 | } | |
802 | } | |
803 | } | |
804 | ||
805 | ||
806 | /* | |
807 | * Check for quiet login, either .hushlogin or command given. | |
808 | */ | |
809 | int | |
810 | check_quietlogin(Session *s, const char *command) | |
811 | { | |
812 | char buf[256]; | |
813 | struct passwd *pw = s->pw; | |
814 | struct stat st; | |
815 | ||
816 | /* Return 1 if .hushlogin exists or a command given. */ | |
817 | if (command != NULL) | |
818 | return 1; | |
819 | snprintf(buf, sizeof(buf), "%.200s/.hushlogin", pw->pw_dir); | |
820 | #ifdef HAVE_LOGIN_CAP | |
821 | if (login_getcapbool(lc, "hushlogin", 0) || stat(buf, &st) >= 0) | |
822 | return 1; | |
823 | #else | |
824 | if (stat(buf, &st) >= 0) | |
825 | return 1; | |
826 | #endif | |
827 | return 0; | |
828 | } | |
829 | ||
830 | /* | |
831 | * Sets the value of the given variable in the environment. If the variable | |
832 | * already exists, its value is overriden. | |
833 | */ | |
5598e598 | 834 | void |
3c0ef626 | 835 | child_set_env(char ***envp, u_int *envsizep, const char *name, |
e9702f7d | 836 | const char *value) |
3c0ef626 | 837 | { |
3c0ef626 | 838 | char **env; |
29d88157 | 839 | u_int envsize; |
840 | u_int i, namelen; | |
3c0ef626 | 841 | |
7cac2b65 | 842 | /* |
843 | * If we're passed an uninitialized list, allocate a single null | |
844 | * entry before continuing. | |
845 | */ | |
846 | if (*envp == NULL && *envsizep == 0) { | |
847 | *envp = xmalloc(sizeof(char *)); | |
848 | *envp[0] = NULL; | |
849 | *envsizep = 1; | |
850 | } | |
851 | ||
3c0ef626 | 852 | /* |
853 | * Find the slot where the value should be stored. If the variable | |
854 | * already exists, we reuse the slot; otherwise we append a new slot | |
855 | * at the end of the array, expanding if necessary. | |
856 | */ | |
857 | env = *envp; | |
858 | namelen = strlen(name); | |
859 | for (i = 0; env[i]; i++) | |
860 | if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=') | |
861 | break; | |
862 | if (env[i]) { | |
863 | /* Reuse the slot. */ | |
864 | xfree(env[i]); | |
865 | } else { | |
866 | /* New variable. Expand if necessary. */ | |
29d88157 | 867 | envsize = *envsizep; |
868 | if (i >= envsize - 1) { | |
869 | if (envsize >= 1000) | |
870 | fatal("child_set_env: too many env vars"); | |
871 | envsize += 50; | |
872 | env = (*envp) = xrealloc(env, envsize * sizeof(char *)); | |
873 | *envsizep = envsize; | |
3c0ef626 | 874 | } |
875 | /* Need to set the NULL pointer at end of array beyond the new slot. */ | |
876 | env[i + 1] = NULL; | |
877 | } | |
878 | ||
879 | /* Allocate space and format the variable in the appropriate slot. */ | |
880 | env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1); | |
881 | snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value); | |
882 | } | |
883 | ||
884 | /* | |
885 | * Reads environment variables from the given file and adds/overrides them | |
886 | * into the environment. If the file does not exist, this does nothing. | |
887 | * Otherwise, it must consist of empty lines, comments (line starts with '#') | |
888 | * and assignments of the form name=value. No other forms are allowed. | |
889 | */ | |
890 | static void | |
891 | read_environment_file(char ***env, u_int *envsize, | |
e9702f7d | 892 | const char *filename) |
3c0ef626 | 893 | { |
894 | FILE *f; | |
895 | char buf[4096]; | |
896 | char *cp, *value; | |
276b07a3 | 897 | u_int lineno = 0; |
3c0ef626 | 898 | |
899 | f = fopen(filename, "r"); | |
900 | if (!f) | |
901 | return; | |
902 | ||
903 | while (fgets(buf, sizeof(buf), f)) { | |
276b07a3 | 904 | if (++lineno > 1000) |
905 | fatal("Too many lines in environment file %s", filename); | |
3c0ef626 | 906 | for (cp = buf; *cp == ' ' || *cp == '\t'; cp++) |
907 | ; | |
908 | if (!*cp || *cp == '#' || *cp == '\n') | |
909 | continue; | |
910 | if (strchr(cp, '\n')) | |
911 | *strchr(cp, '\n') = '\0'; | |
912 | value = strchr(cp, '='); | |
913 | if (value == NULL) { | |
276b07a3 | 914 | fprintf(stderr, "Bad line %u in %.100s\n", lineno, |
915 | filename); | |
3c0ef626 | 916 | continue; |
917 | } | |
918 | /* | |
919 | * Replace the equals sign by nul, and advance value to | |
920 | * the value string. | |
921 | */ | |
922 | *value = '\0'; | |
923 | value++; | |
924 | child_set_env(env, envsize, cp, value); | |
925 | } | |
926 | fclose(f); | |
927 | } | |
928 | ||
75be3237 | 929 | #ifdef SESSION_HOOKS |
930 | #define SSH_SESSION_ENV_FILE "SSH_SESSION_ENV_FILE" | |
931 | ||
932 | typedef enum { no_op, execute, clear_env, restore_env, | |
933 | read_env, save_or_rm_env } session_action_t; | |
934 | ||
935 | static session_action_t action_order[2][5] = { | |
936 | { clear_env, read_env, execute, save_or_rm_env, restore_env }, /*shutdown*/ | |
937 | { execute, read_env, save_or_rm_env, no_op, no_op } /*startup */ | |
938 | }; | |
939 | ||
940 | static | |
941 | void execute_session_hook(char* prog, Authctxt *authctxt, | |
942 | int startup, int save) | |
943 | { | |
944 | extern char **environ; | |
945 | ||
946 | struct stat st; | |
947 | char **saved_env, **tmpenv; | |
948 | char *env_file = authctxt->session_env_file; | |
949 | int i, status = 0; | |
950 | ||
951 | for (i=0; i<5; i++) | |
952 | { | |
953 | switch (action_order[startup][i]) | |
954 | { | |
955 | case no_op: | |
956 | break; | |
957 | ||
958 | case execute: | |
959 | { | |
960 | FILE* fp; | |
961 | char buf[1000]; | |
962 | ||
963 | snprintf(buf, | |
964 | sizeof(buf), | |
965 | "%s -c '%s'", | |
966 | authctxt->pw->pw_shell, | |
967 | prog); | |
968 | ||
969 | debug("executing session hook: [%s]", buf); | |
970 | setenv(SSH_SESSION_ENV_FILE, env_file, /* overwrite = */ 1); | |
971 | ||
972 | /* flusing is recommended in the popen(3) man page, to avoid | |
973 | intermingling of output */ | |
974 | fflush(stdout); | |
975 | fflush(stderr); | |
976 | if ((fp=popen(buf, "w")) == NULL) | |
977 | { | |
978 | perror("Unable to run session hook"); | |
979 | return; | |
980 | } | |
981 | status = pclose(fp); | |
982 | debug2("session hook executed, status=%d", status); | |
983 | unsetenv(SSH_SESSION_ENV_FILE); | |
984 | } | |
985 | break; | |
986 | ||
987 | case clear_env: | |
988 | saved_env = environ; | |
989 | tmpenv = (char**) malloc(sizeof(char*)); | |
990 | tmpenv[0] = NULL; | |
991 | environ = tmpenv; | |
992 | break; | |
993 | ||
994 | case restore_env: | |
995 | environ = saved_env; | |
996 | free(tmpenv); | |
997 | break; | |
998 | ||
999 | case read_env: | |
1000 | if (status==0 && stat(env_file, &st)==0) | |
1001 | { | |
1002 | int envsize = 0; | |
1003 | ||
1004 | debug("reading environment from %s", env_file); | |
1005 | while (environ[envsize++]) ; | |
1006 | read_environment_file(&environ, &envsize, env_file); | |
1007 | } | |
1008 | break; | |
1009 | ||
1010 | case save_or_rm_env: | |
1011 | if (status==0 && save) | |
1012 | { | |
1013 | FILE* fp; | |
1014 | int envcount=0; | |
1015 | ||
1016 | debug2("saving environment to %s", env_file); | |
1017 | if ((fp = fopen(env_file, "w")) == NULL) /* hmm: file perms? */ | |
1018 | { | |
1019 | perror("Unable to save session hook info"); | |
1020 | } | |
1021 | while (environ[envcount]) | |
1022 | { | |
1023 | fprintf(fp, "%s\n", environ[envcount++]); | |
1024 | } | |
1025 | fflush(fp); | |
1026 | fclose(fp); | |
1027 | } | |
1028 | else if (stat(env_file, &st)==0) | |
1029 | { | |
1030 | debug2("removing environment file %s", env_file); | |
1031 | remove(env_file); | |
1032 | } | |
1033 | break; | |
1034 | } | |
1035 | } | |
1036 | ||
1037 | } | |
1038 | #endif | |
1039 | ||
7cac2b65 | 1040 | #ifdef HAVE_ETC_DEFAULT_LOGIN |
1041 | /* | |
1042 | * Return named variable from specified environment, or NULL if not present. | |
1043 | */ | |
1044 | static char * | |
1045 | child_get_env(char **env, const char *name) | |
1046 | { | |
1047 | int i; | |
1048 | size_t len; | |
1049 | ||
1050 | len = strlen(name); | |
1051 | for (i=0; env[i] != NULL; i++) | |
1052 | if (strncmp(name, env[i], len) == 0 && env[i][len] == '=') | |
1053 | return(env[i] + len + 1); | |
1054 | return NULL; | |
1055 | } | |
1056 | ||
1057 | /* | |
1058 | * Read /etc/default/login. | |
1059 | * We pick up the PATH (or SUPATH for root) and UMASK. | |
1060 | */ | |
1061 | static void | |
1062 | read_etc_default_login(char ***env, u_int *envsize, uid_t uid) | |
1063 | { | |
1064 | char **tmpenv = NULL, *var; | |
29d88157 | 1065 | u_int i, tmpenvsize = 0; |
540d72c3 | 1066 | u_long mask; |
7cac2b65 | 1067 | |
1068 | /* | |
1069 | * We don't want to copy the whole file to the child's environment, | |
1070 | * so we use a temporary environment and copy the variables we're | |
1071 | * interested in. | |
1072 | */ | |
1073 | read_environment_file(&tmpenv, &tmpenvsize, "/etc/default/login"); | |
1074 | ||
29d88157 | 1075 | if (tmpenv == NULL) |
1076 | return; | |
1077 | ||
7cac2b65 | 1078 | if (uid == 0) |
1079 | var = child_get_env(tmpenv, "SUPATH"); | |
1080 | else | |
1081 | var = child_get_env(tmpenv, "PATH"); | |
1082 | if (var != NULL) | |
1083 | child_set_env(env, envsize, "PATH", var); | |
540d72c3 | 1084 | |
7cac2b65 | 1085 | if ((var = child_get_env(tmpenv, "UMASK")) != NULL) |
1086 | if (sscanf(var, "%5lo", &mask) == 1) | |
540d72c3 | 1087 | umask((mode_t)mask); |
1088 | ||
7cac2b65 | 1089 | for (i = 0; tmpenv[i] != NULL; i++) |
1090 | xfree(tmpenv[i]); | |
1091 | xfree(tmpenv); | |
1092 | } | |
1093 | #endif /* HAVE_ETC_DEFAULT_LOGIN */ | |
1094 | ||
2ce0bfe4 | 1095 | void |
1096 | copy_environment(char **source, char ***env, u_int *envsize) | |
3c0ef626 | 1097 | { |
e9702f7d | 1098 | char *var_name, *var_val; |
3c0ef626 | 1099 | int i; |
1100 | ||
e9702f7d | 1101 | if (source == NULL) |
3c0ef626 | 1102 | return; |
1103 | ||
e9702f7d | 1104 | for(i = 0; source[i] != NULL; i++) { |
1105 | var_name = xstrdup(source[i]); | |
1106 | if ((var_val = strstr(var_name, "=")) == NULL) { | |
1107 | xfree(var_name); | |
3c0ef626 | 1108 | continue; |
3c0ef626 | 1109 | } |
e9702f7d | 1110 | *var_val++ = '\0'; |
3c0ef626 | 1111 | |
e9702f7d | 1112 | debug3("Copy environment: %s=%s", var_name, var_val); |
1113 | child_set_env(env, envsize, var_name, var_val); | |
540d72c3 | 1114 | |
e9702f7d | 1115 | xfree(var_name); |
3c0ef626 | 1116 | } |
3c0ef626 | 1117 | } |
1118 | ||
e9702f7d | 1119 | static char ** |
1120 | do_setup_env(Session *s, const char *shell) | |
3c0ef626 | 1121 | { |
3c0ef626 | 1122 | char buf[256]; |
e9702f7d | 1123 | u_int i, envsize; |
7cac2b65 | 1124 | char **env, *laddr, *path = NULL; |
e9702f7d | 1125 | struct passwd *pw = s->pw; |
3c0ef626 | 1126 | |
1127 | /* Initialize the environment. */ | |
1128 | envsize = 100; | |
1129 | env = xmalloc(envsize * sizeof(char *)); | |
1130 | env[0] = NULL; | |
1131 | ||
1132 | #ifdef HAVE_CYGWIN | |
1133 | /* | |
1134 | * The Windows environment contains some setting which are | |
1135 | * important for a running system. They must not be dropped. | |
1136 | */ | |
dfddba3d | 1137 | { |
1138 | char **p; | |
1139 | ||
1140 | p = fetch_windows_environment(); | |
1141 | copy_environment(p, &env, &envsize); | |
1142 | free_windows_environment(p); | |
1143 | } | |
3c0ef626 | 1144 | #endif |
1145 | ||
5598e598 | 1146 | #ifdef GSSAPI |
540d72c3 | 1147 | /* Allow any GSSAPI methods that we've used to alter |
5598e598 | 1148 | * the childs environment as they see fit |
1149 | */ | |
7cac2b65 | 1150 | ssh_gssapi_do_child(&env, &envsize); |
5598e598 | 1151 | #endif |
1152 | ||
3c0ef626 | 1153 | if (!options.use_login) { |
1154 | /* Set basic environment. */ | |
7e82606e | 1155 | for (i = 0; i < s->num_env; i++) |
1156 | child_set_env(&env, &envsize, s->env[i].name, | |
1157 | s->env[i].val); | |
1158 | ||
3c0ef626 | 1159 | child_set_env(&env, &envsize, "USER", pw->pw_name); |
1160 | child_set_env(&env, &envsize, "LOGNAME", pw->pw_name); | |
bfe49944 | 1161 | #ifdef _AIX |
1162 | child_set_env(&env, &envsize, "LOGIN", pw->pw_name); | |
1163 | #endif | |
3c0ef626 | 1164 | child_set_env(&env, &envsize, "HOME", pw->pw_dir); |
1165 | #ifdef HAVE_LOGIN_CAP | |
d03f4262 | 1166 | if (setusercontext(lc, pw, pw->pw_uid, LOGIN_SETPATH) < 0) |
1167 | child_set_env(&env, &envsize, "PATH", _PATH_STDPATH); | |
1168 | else | |
1169 | child_set_env(&env, &envsize, "PATH", getenv("PATH")); | |
3c0ef626 | 1170 | #else /* HAVE_LOGIN_CAP */ |
1171 | # ifndef HAVE_CYGWIN | |
1172 | /* | |
1173 | * There's no standard path on Windows. The path contains | |
1174 | * important components pointing to the system directories, | |
1175 | * needed for loading shared libraries. So the path better | |
1176 | * remains intact here. | |
1177 | */ | |
7cac2b65 | 1178 | # ifdef HAVE_ETC_DEFAULT_LOGIN |
1179 | read_etc_default_login(&env, &envsize, pw->pw_uid); | |
1180 | path = child_get_env(env, "PATH"); | |
1181 | # endif /* HAVE_ETC_DEFAULT_LOGIN */ | |
1182 | if (path == NULL || *path == '\0') { | |
540d72c3 | 1183 | child_set_env(&env, &envsize, "PATH", |
7cac2b65 | 1184 | s->pw->pw_uid == 0 ? |
1185 | SUPERUSER_PATH : _PATH_STDPATH); | |
1186 | } | |
3c0ef626 | 1187 | # endif /* HAVE_CYGWIN */ |
1188 | #endif /* HAVE_LOGIN_CAP */ | |
1189 | ||
1190 | snprintf(buf, sizeof buf, "%.200s/%.50s", | |
1191 | _PATH_MAILDIR, pw->pw_name); | |
1192 | child_set_env(&env, &envsize, "MAIL", buf); | |
1193 | ||
1194 | /* Normal systems set SHELL by default. */ | |
1195 | child_set_env(&env, &envsize, "SHELL", shell); | |
1196 | } | |
1197 | if (getenv("TZ")) | |
1198 | child_set_env(&env, &envsize, "TZ", getenv("TZ")); | |
1199 | ||
1752c22a | 1200 | #ifdef GSI /* GSI shared libs typically installed in non-system locations. */ |
1201 | { | |
1202 | char *cp; | |
1203 | ||
1204 | if ((cp = getenv("LD_LIBRARY_PATH")) != NULL) | |
1205 | child_set_env(&env, &envsize, "LD_LIBRARY_PATH", cp); | |
1206 | if ((cp = getenv("LIBPATH")) != NULL) | |
1207 | child_set_env(&env, &envsize, "LIBPATH", cp); | |
1208 | if ((cp = getenv("SHLIB_PATH")) != NULL) | |
1209 | child_set_env(&env, &envsize, "SHLIB_PATH", cp); | |
1210 | if ((cp = getenv("LD_LIBRARYN32_PATH")) != NULL) | |
1211 | child_set_env(&env, &envsize, "LD_LIBRARYN32_PATH",cp); | |
1212 | if ((cp = getenv("LD_LIBRARY64_PATH")) != NULL) | |
1213 | child_set_env(&env, &envsize, "LD_LIBRARY64_PATH",cp); | |
1214 | } | |
1215 | #endif | |
1216 | ||
3c0ef626 | 1217 | /* Set custom environment options from RSA authentication. */ |
1218 | if (!options.use_login) { | |
1219 | while (custom_environment) { | |
1220 | struct envstring *ce = custom_environment; | |
d03f4262 | 1221 | char *str = ce->s; |
e9702f7d | 1222 | |
d03f4262 | 1223 | for (i = 0; str[i] != '=' && str[i]; i++) |
3c0ef626 | 1224 | ; |
d03f4262 | 1225 | if (str[i] == '=') { |
1226 | str[i] = 0; | |
1227 | child_set_env(&env, &envsize, str, str + i + 1); | |
3c0ef626 | 1228 | } |
1229 | custom_environment = ce->next; | |
1230 | xfree(ce->s); | |
1231 | xfree(ce); | |
1232 | } | |
1233 | } | |
1234 | ||
d03f4262 | 1235 | /* SSH_CLIENT deprecated */ |
3c0ef626 | 1236 | snprintf(buf, sizeof buf, "%.50s %d %d", |
e9702f7d | 1237 | get_remote_ipaddr(), get_remote_port(), get_local_port()); |
3c0ef626 | 1238 | child_set_env(&env, &envsize, "SSH_CLIENT", buf); |
1239 | ||
bfe49944 | 1240 | laddr = get_local_ipaddr(packet_get_connection_in()); |
d03f4262 | 1241 | snprintf(buf, sizeof buf, "%.50s %d %.50s %d", |
bfe49944 | 1242 | get_remote_ipaddr(), get_remote_port(), laddr, get_local_port()); |
1243 | xfree(laddr); | |
d03f4262 | 1244 | child_set_env(&env, &envsize, "SSH_CONNECTION", buf); |
1245 | ||
3c0ef626 | 1246 | if (s->ttyfd != -1) |
1247 | child_set_env(&env, &envsize, "SSH_TTY", s->tty); | |
1248 | if (s->term) | |
1249 | child_set_env(&env, &envsize, "TERM", s->term); | |
1250 | if (s->display) | |
1251 | child_set_env(&env, &envsize, "DISPLAY", s->display); | |
1252 | if (original_command) | |
1253 | child_set_env(&env, &envsize, "SSH_ORIGINAL_COMMAND", | |
1254 | original_command); | |
1255 | ||
d03f4262 | 1256 | #ifdef _UNICOS |
1257 | if (cray_tmpdir[0] != '\0') | |
1258 | child_set_env(&env, &envsize, "TMPDIR", cray_tmpdir); | |
1259 | #endif /* _UNICOS */ | |
1260 | ||
dfddba3d | 1261 | /* |
1262 | * Since we clear KRB5CCNAME at startup, if it's set now then it | |
1263 | * must have been set by a native authentication method (eg AIX or | |
1264 | * SIA), so copy it to the child. | |
1265 | */ | |
1266 | { | |
1267 | char *cp; | |
1268 | ||
1269 | if ((cp = getenv("KRB5CCNAME")) != NULL) | |
1270 | child_set_env(&env, &envsize, "KRB5CCNAME", cp); | |
1271 | } | |
1272 | ||
3c0ef626 | 1273 | #ifdef _AIX |
e9702f7d | 1274 | { |
1275 | char *cp; | |
1276 | ||
1277 | if ((cp = getenv("AUTHSTATE")) != NULL) | |
1278 | child_set_env(&env, &envsize, "AUTHSTATE", cp); | |
e9702f7d | 1279 | read_environment_file(&env, &envsize, "/etc/environment"); |
1280 | } | |
3c0ef626 | 1281 | #endif |
3c0ef626 | 1282 | #ifdef KRB5 |
12a403af | 1283 | if (s->authctxt->krb5_ccname) |
3c0ef626 | 1284 | child_set_env(&env, &envsize, "KRB5CCNAME", |
12a403af | 1285 | s->authctxt->krb5_ccname); |
3c0ef626 | 1286 | #endif |
1287 | #ifdef USE_PAM | |
d03f4262 | 1288 | /* |
1289 | * Pull in any environment variables that may have | |
1290 | * been set by PAM. | |
1291 | */ | |
7cac2b65 | 1292 | if (options.use_pam) { |
540d72c3 | 1293 | char **p; |
d03f4262 | 1294 | |
540d72c3 | 1295 | p = fetch_pam_child_environment(); |
1296 | copy_environment(p, &env, &envsize); | |
1297 | free_pam_environment(p); | |
1298 | ||
1299 | p = fetch_pam_environment(); | |
d03f4262 | 1300 | copy_environment(p, &env, &envsize); |
1301 | free_pam_environment(p); | |
1302 | } | |
3c0ef626 | 1303 | #endif /* USE_PAM */ |
1304 | ||
44a053a3 | 1305 | if (auth_sock_name != NULL) |
3c0ef626 | 1306 | child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME, |
44a053a3 | 1307 | auth_sock_name); |
3c0ef626 | 1308 | |
1309 | /* read $HOME/.ssh/environment. */ | |
d03f4262 | 1310 | if (options.permit_user_env && !options.use_login) { |
3c0ef626 | 1311 | snprintf(buf, sizeof buf, "%.200s/.ssh/environment", |
d03f4262 | 1312 | strcmp(pw->pw_dir, "/") ? pw->pw_dir : ""); |
3c0ef626 | 1313 | read_environment_file(&env, &envsize, buf); |
1314 | } | |
1315 | if (debug_flag) { | |
1316 | /* dump the environment */ | |
1317 | fprintf(stderr, "Environment:\n"); | |
1318 | for (i = 0; env[i]; i++) | |
1319 | fprintf(stderr, " %.200s\n", env[i]); | |
1320 | } | |
e9702f7d | 1321 | return env; |
1322 | } | |
1323 | ||
1324 | /* | |
1325 | * Run $HOME/.ssh/rc, /etc/ssh/sshrc, or xauth (whichever is found | |
1326 | * first in this order). | |
1327 | */ | |
1328 | static void | |
1329 | do_rc_files(Session *s, const char *shell) | |
1330 | { | |
1331 | FILE *f = NULL; | |
1332 | char cmd[1024]; | |
1333 | int do_xauth; | |
1334 | struct stat st; | |
1335 | ||
1336 | do_xauth = | |
1337 | s->display != NULL && s->auth_proto != NULL && s->auth_data != NULL; | |
1338 | ||
1339 | /* ignore _PATH_SSH_USER_RC for subsystems */ | |
1340 | if (!s->is_subsystem && (stat(_PATH_SSH_USER_RC, &st) >= 0)) { | |
1341 | snprintf(cmd, sizeof cmd, "%s -c '%s %s'", | |
1342 | shell, _PATH_BSHELL, _PATH_SSH_USER_RC); | |
1343 | if (debug_flag) | |
1344 | fprintf(stderr, "Running %s\n", cmd); | |
1345 | f = popen(cmd, "w"); | |
1346 | if (f) { | |
1347 | if (do_xauth) | |
1348 | fprintf(f, "%s %s\n", s->auth_proto, | |
1349 | s->auth_data); | |
1350 | pclose(f); | |
1351 | } else | |
1352 | fprintf(stderr, "Could not run %s\n", | |
1353 | _PATH_SSH_USER_RC); | |
1354 | } else if (stat(_PATH_SSH_SYSTEM_RC, &st) >= 0) { | |
1355 | if (debug_flag) | |
1356 | fprintf(stderr, "Running %s %s\n", _PATH_BSHELL, | |
1357 | _PATH_SSH_SYSTEM_RC); | |
1358 | f = popen(_PATH_BSHELL " " _PATH_SSH_SYSTEM_RC, "w"); | |
1359 | if (f) { | |
1360 | if (do_xauth) | |
1361 | fprintf(f, "%s %s\n", s->auth_proto, | |
1362 | s->auth_data); | |
1363 | pclose(f); | |
1364 | } else | |
1365 | fprintf(stderr, "Could not run %s\n", | |
1366 | _PATH_SSH_SYSTEM_RC); | |
1367 | } else if (do_xauth && options.xauth_location != NULL) { | |
1368 | /* Add authority data to .Xauthority if appropriate. */ | |
1369 | if (debug_flag) { | |
1370 | fprintf(stderr, | |
bfe49944 | 1371 | "Running %.500s remove %.100s\n", |
540d72c3 | 1372 | options.xauth_location, s->auth_display); |
bfe49944 | 1373 | fprintf(stderr, |
1374 | "%.500s add %.100s %.100s %.100s\n", | |
e9702f7d | 1375 | options.xauth_location, s->auth_display, |
1376 | s->auth_proto, s->auth_data); | |
1377 | } | |
1378 | snprintf(cmd, sizeof cmd, "%s -q -", | |
1379 | options.xauth_location); | |
1380 | f = popen(cmd, "w"); | |
1381 | if (f) { | |
bfe49944 | 1382 | fprintf(f, "remove %s\n", |
1383 | s->auth_display); | |
e9702f7d | 1384 | fprintf(f, "add %s %s %s\n", |
1385 | s->auth_display, s->auth_proto, | |
1386 | s->auth_data); | |
1387 | pclose(f); | |
1388 | } else { | |
1389 | fprintf(stderr, "Could not run %s\n", | |
1390 | cmd); | |
1391 | } | |
1392 | } | |
1393 | } | |
1394 | ||
1395 | static void | |
1396 | do_nologin(struct passwd *pw) | |
1397 | { | |
1398 | FILE *f = NULL; | |
1399 | char buf[1024]; | |
1400 | ||
1401 | #ifdef HAVE_LOGIN_CAP | |
1402 | if (!login_getcapbool(lc, "ignorenologin", 0) && pw->pw_uid) | |
1403 | f = fopen(login_getcapstr(lc, "nologin", _PATH_NOLOGIN, | |
1404 | _PATH_NOLOGIN), "r"); | |
1405 | #else | |
1406 | if (pw->pw_uid) | |
1407 | f = fopen(_PATH_NOLOGIN, "r"); | |
1408 | #endif | |
1409 | if (f) { | |
1410 | /* /etc/nologin exists. Print its contents and exit. */ | |
7cac2b65 | 1411 | logit("User %.100s not allowed because %s exists", |
d03f4262 | 1412 | pw->pw_name, _PATH_NOLOGIN); |
e9702f7d | 1413 | while (fgets(buf, sizeof(buf), f)) |
1414 | fputs(buf, stderr); | |
1415 | fclose(f); | |
bfe49944 | 1416 | fflush(NULL); |
e9702f7d | 1417 | exit(254); |
1418 | } | |
1419 | } | |
1420 | ||
1421 | /* Set login name, uid, gid, and groups. */ | |
350391c5 | 1422 | void |
e9702f7d | 1423 | do_setusercontext(struct passwd *pw) |
1424 | { | |
bfe49944 | 1425 | #ifndef HAVE_CYGWIN |
1426 | if (getuid() == 0 || geteuid() == 0) | |
e9702f7d | 1427 | #endif /* HAVE_CYGWIN */ |
bfe49944 | 1428 | { |
1429 | ||
44a053a3 | 1430 | #ifdef HAVE_SETPCRED |
7cac2b65 | 1431 | if (setpcred(pw->pw_name, (char **)NULL) == -1) |
1432 | fatal("Failed to set process credentials"); | |
44a053a3 | 1433 | #endif /* HAVE_SETPCRED */ |
e9702f7d | 1434 | #ifdef HAVE_LOGIN_CAP |
d03f4262 | 1435 | # ifdef __bsdi__ |
276b07a3 | 1436 | setpgid(0, 0); |
d03f4262 | 1437 | # endif |
dfddba3d | 1438 | #ifdef GSSAPI |
1439 | if (options.gss_authentication) { | |
1440 | temporarily_use_uid(pw); | |
1441 | ssh_gssapi_storecreds(); | |
1442 | restore_uid(); | |
1443 | } | |
1444 | #endif | |
540d72c3 | 1445 | # ifdef USE_PAM |
1446 | if (options.use_pam) { | |
1447 | do_pam_session(); | |
1448 | do_pam_setcred(0); | |
1449 | } | |
1450 | # endif /* USE_PAM */ | |
e9702f7d | 1451 | if (setusercontext(lc, pw, pw->pw_uid, |
1452 | (LOGIN_SETALL & ~LOGIN_SETPATH)) < 0) { | |
1453 | perror("unable to set user context"); | |
1454 | exit(1); | |
1455 | } | |
1456 | #else | |
1457 | # if defined(HAVE_GETLUID) && defined(HAVE_SETLUID) | |
1458 | /* Sets login uid for accounting */ | |
1459 | if (getluid() == -1 && setluid(pw->pw_uid) == -1) | |
1460 | error("setluid: %s", strerror(errno)); | |
1461 | # endif /* defined(HAVE_GETLUID) && defined(HAVE_SETLUID) */ | |
1462 | ||
1463 | if (setlogin(pw->pw_name) < 0) | |
1464 | error("setlogin failed: %s", strerror(errno)); | |
1465 | if (setgid(pw->pw_gid) < 0) { | |
1466 | perror("setgid"); | |
1467 | exit(1); | |
1468 | } | |
1469 | /* Initialize the group list. */ | |
1470 | if (initgroups(pw->pw_name, pw->pw_gid) < 0) { | |
1471 | perror("initgroups"); | |
1472 | exit(1); | |
1473 | } | |
1474 | endgrent(); | |
dfddba3d | 1475 | #ifdef GSSAPI |
1476 | if (options.gss_authentication) { | |
1477 | temporarily_use_uid(pw); | |
1478 | ssh_gssapi_storecreds(); | |
1479 | restore_uid(); | |
1480 | } | |
1481 | #endif | |
e9702f7d | 1482 | # ifdef USE_PAM |
1483 | /* | |
540d72c3 | 1484 | * PAM credentials may take the form of supplementary groups. |
e9702f7d | 1485 | * These will have been wiped by the above initgroups() call. |
1486 | * Reestablish them here. | |
1487 | */ | |
7cac2b65 | 1488 | if (options.use_pam) { |
1489 | do_pam_session(); | |
1490 | do_pam_setcred(0); | |
1491 | } | |
e9702f7d | 1492 | # endif /* USE_PAM */ |
1493 | # if defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) | |
1494 | irix_setusercontext(pw); | |
1495 | # endif /* defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) */ | |
276b07a3 | 1496 | # ifdef _AIX |
d03f4262 | 1497 | aix_usrinfo(pw); |
276b07a3 | 1498 | # endif /* _AIX */ |
2ce0bfe4 | 1499 | #if defined(HAVE_LIBIAF) && !defined(BROKEN_LIBIAF) |
1500 | if (set_id(pw->pw_name) != 0) { | |
1501 | exit(1); | |
1502 | } | |
1503 | #endif /* HAVE_LIBIAF && !BROKEN_LIBIAF */ | |
e9702f7d | 1504 | /* Permanently switch to the desired uid. */ |
1505 | permanently_set_uid(pw); | |
1506 | #endif | |
1507 | } | |
bfe49944 | 1508 | |
1509 | #ifdef HAVE_CYGWIN | |
1510 | if (is_winnt) | |
1511 | #endif | |
e9702f7d | 1512 | if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid) |
1513 | fatal("Failed to set uids to %u.", (u_int) pw->pw_uid); | |
1514 | } | |
1515 | ||
540d72c3 | 1516 | static void |
1517 | do_pwchange(Session *s) | |
1518 | { | |
7e82606e | 1519 | fflush(NULL); |
540d72c3 | 1520 | fprintf(stderr, "WARNING: Your password has expired.\n"); |
1521 | if (s->ttyfd != -1) { | |
7e82606e | 1522 | fprintf(stderr, |
540d72c3 | 1523 | "You must change your password now and login again!\n"); |
dfddba3d | 1524 | #ifdef PASSWD_NEEDS_USERNAME |
1525 | execl(_PATH_PASSWD_PROG, "passwd", s->pw->pw_name, | |
1526 | (char *)NULL); | |
1527 | #else | |
540d72c3 | 1528 | execl(_PATH_PASSWD_PROG, "passwd", (char *)NULL); |
dfddba3d | 1529 | #endif |
540d72c3 | 1530 | perror("passwd"); |
1531 | } else { | |
1532 | fprintf(stderr, | |
1533 | "Password change required but no TTY available.\n"); | |
1534 | } | |
1535 | exit(1); | |
1536 | } | |
1537 | ||
350391c5 | 1538 | static void |
1539 | launch_login(struct passwd *pw, const char *hostname) | |
1540 | { | |
1541 | /* Launch login(1). */ | |
1542 | ||
44a053a3 | 1543 | execl(LOGIN_PROGRAM, "login", "-h", hostname, |
350391c5 | 1544 | #ifdef xxxLOGIN_NEEDS_TERM |
44a053a3 | 1545 | (s->term ? s->term : "unknown"), |
350391c5 | 1546 | #endif /* LOGIN_NEEDS_TERM */ |
1547 | #ifdef LOGIN_NO_ENDOPT | |
1548 | "-p", "-f", pw->pw_name, (char *)NULL); | |
1549 | #else | |
1550 | "-p", "-f", "--", pw->pw_name, (char *)NULL); | |
1551 | #endif | |
1552 | ||
1553 | /* Login couldn't be executed, die. */ | |
1554 | ||
1555 | perror("login"); | |
1556 | exit(1); | |
1557 | } | |
1558 | ||
540d72c3 | 1559 | static void |
1560 | child_close_fds(void) | |
1561 | { | |
1562 | int i; | |
1563 | ||
1564 | if (packet_get_connection_in() == packet_get_connection_out()) | |
1565 | close(packet_get_connection_in()); | |
1566 | else { | |
1567 | close(packet_get_connection_in()); | |
1568 | close(packet_get_connection_out()); | |
1569 | } | |
1570 | /* | |
1571 | * Close all descriptors related to channels. They will still remain | |
1572 | * open in the parent. | |
1573 | */ | |
1574 | /* XXX better use close-on-exec? -markus */ | |
1575 | channel_close_all(); | |
1576 | ||
1577 | /* | |
1578 | * Close any extra file descriptors. Note that there may still be | |
1579 | * descriptors left by system functions. They will be closed later. | |
1580 | */ | |
1581 | endpwent(); | |
1582 | ||
1583 | /* | |
08822d99 | 1584 | * Close any extra open file descriptors so that we don't have them |
540d72c3 | 1585 | * hanging around in clients. Note that we want to do this after |
1586 | * initgroups, because at least on Solaris 2.3 it leaves file | |
1587 | * descriptors open. | |
1588 | */ | |
1589 | for (i = 3; i < 64; i++) | |
1590 | close(i); | |
1591 | } | |
1592 | ||
e9702f7d | 1593 | /* |
1594 | * Performs common processing for the child, such as setting up the | |
1595 | * environment, closing extra file descriptors, setting the user and group | |
1596 | * ids, and executing the command or shell. | |
1597 | */ | |
1598 | void | |
1599 | do_child(Session *s, const char *command) | |
1600 | { | |
1601 | extern char **environ; | |
1602 | char **env; | |
1603 | char *argv[10]; | |
1604 | const char *shell, *shell0, *hostname = NULL; | |
1605 | struct passwd *pw = s->pw; | |
e9702f7d | 1606 | |
62eb343a | 1607 | #ifdef AFS_KRB5 |
1608 | /* Default place to look for aklog. */ | |
1609 | #ifdef AKLOG_PATH | |
1610 | #define KPROGDIR AKLOG_PATH | |
1611 | #else | |
1612 | #define KPROGDIR "/usr/bin/aklog" | |
1613 | #endif /* AKLOG_PATH */ | |
1614 | ||
1615 | struct stat st; | |
1616 | char *aklog_path; | |
1617 | #endif /* AFS_KRB5 */ | |
1618 | ||
e9702f7d | 1619 | /* remove hostkey from the child's memory */ |
1620 | destroy_sensitive_data(); | |
1621 | ||
540d72c3 | 1622 | /* Force a password change */ |
1623 | if (s->authctxt->force_pwchange) { | |
1624 | do_setusercontext(pw); | |
1625 | child_close_fds(); | |
1626 | do_pwchange(s); | |
1627 | exit(1); | |
1628 | } | |
1629 | ||
e9702f7d | 1630 | /* login(1) is only called if we execute the login shell */ |
1631 | if (options.use_login && command != NULL) | |
1632 | options.use_login = 0; | |
1633 | ||
d03f4262 | 1634 | #ifdef _UNICOS |
1635 | cray_setup(pw->pw_uid, pw->pw_name, command); | |
1636 | #endif /* _UNICOS */ | |
1637 | ||
e9702f7d | 1638 | /* |
1639 | * Login(1) does this as well, and it needs uid 0 for the "-h" | |
1640 | * switch, so we let login(1) to this for us. | |
1641 | */ | |
1642 | if (!options.use_login) { | |
1643 | #ifdef HAVE_OSF_SIA | |
bfe49944 | 1644 | session_setup_sia(pw, s->ttyfd == -1 ? NULL : s->tty); |
e9702f7d | 1645 | if (!check_quietlogin(s, command)) |
1646 | do_motd(); | |
1647 | #else /* HAVE_OSF_SIA */ | |
08822d99 | 1648 | /* When PAM is enabled we rely on it to do the nologin check */ |
1649 | if (!options.use_pam) | |
1650 | do_nologin(pw); | |
e9702f7d | 1651 | do_setusercontext(pw); |
7e82606e | 1652 | /* |
1653 | * PAM session modules in do_setusercontext may have | |
1654 | * generated messages, so if this in an interactive | |
1655 | * login then display them too. | |
1656 | */ | |
dfddba3d | 1657 | if (!check_quietlogin(s, command)) |
7e82606e | 1658 | display_loginmsg(); |
e9702f7d | 1659 | #endif /* HAVE_OSF_SIA */ |
1660 | } | |
1661 | ||
dfddba3d | 1662 | #ifdef USE_PAM |
8b32eddc | 1663 | if (options.use_pam && !options.use_login && !is_pam_session_open()) { |
1664 | debug3("PAM session not opened, exiting"); | |
dfddba3d | 1665 | display_loginmsg(); |
1666 | exit(254); | |
1667 | } | |
1668 | #endif | |
1669 | ||
e9702f7d | 1670 | /* |
1671 | * Get the shell from the password data. An empty shell field is | |
1672 | * legal, and means /bin/sh. | |
1673 | */ | |
1674 | shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell; | |
bfe49944 | 1675 | |
1676 | /* | |
1677 | * Make sure $SHELL points to the shell from the password file, | |
1678 | * even if shell is overridden from login.conf | |
1679 | */ | |
1680 | env = do_setup_env(s, shell); | |
1681 | ||
e9702f7d | 1682 | #ifdef HAVE_LOGIN_CAP |
1683 | shell = login_getcapstr(lc, "shell", (char *)shell, (char *)shell); | |
1684 | #endif | |
1685 | ||
3c0ef626 | 1686 | /* we have to stash the hostname before we close our socket. */ |
1687 | if (options.use_login) | |
1688 | hostname = get_remote_name_or_ip(utmp_len, | |
7cac2b65 | 1689 | options.use_dns); |
3c0ef626 | 1690 | /* |
1691 | * Close the connection descriptors; note that this is the child, and | |
1692 | * the server will still have the socket open, and it is important | |
1693 | * that we do not shutdown it. Note that the descriptors cannot be | |
1694 | * closed before building the environment, as we call | |
1695 | * get_remote_ipaddr there. | |
1696 | */ | |
540d72c3 | 1697 | child_close_fds(); |
3c0ef626 | 1698 | |
1699 | /* | |
540d72c3 | 1700 | * Must take new environment into use so that .ssh/rc, |
1701 | * /etc/ssh/sshrc and xauth are run in the proper environment. | |
3c0ef626 | 1702 | */ |
540d72c3 | 1703 | environ = env; |
3c0ef626 | 1704 | |
540d72c3 | 1705 | #if defined(KRB5) && defined(USE_AFS) |
3c0ef626 | 1706 | /* |
540d72c3 | 1707 | * At this point, we check to see if AFS is active and if we have |
1708 | * a valid Kerberos 5 TGT. If so, it seems like a good idea to see | |
1709 | * if we can (and need to) extend the ticket into an AFS token. If | |
1710 | * we don't do this, we run into potential problems if the user's | |
1711 | * home directory is in AFS and it's not world-readable. | |
3c0ef626 | 1712 | */ |
3c0ef626 | 1713 | |
540d72c3 | 1714 | if (options.kerberos_get_afs_token && k_hasafs() && |
2ce0bfe4 | 1715 | (s->authctxt->krb5_ctx != NULL)) { |
540d72c3 | 1716 | char cell[64]; |
1717 | ||
1718 | debug("Getting AFS token"); | |
1719 | ||
1720 | k_setpag(); | |
1721 | ||
1722 | if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0) | |
1723 | krb5_afslog(s->authctxt->krb5_ctx, | |
1724 | s->authctxt->krb5_fwd_ccache, cell, NULL); | |
1725 | ||
1726 | krb5_afslog_home(s->authctxt->krb5_ctx, | |
1727 | s->authctxt->krb5_fwd_ccache, NULL, NULL, pw->pw_dir); | |
1728 | } | |
1729 | #endif | |
3c0ef626 | 1730 | |
62eb343a | 1731 | #ifdef AFS_KRB5 |
1732 | ||
1733 | /* User has authenticated, and if a ticket was going to be | |
1734 | * passed we would have it. KRB5CCNAME should already be set. | |
1735 | * Now try to get an AFS token using aklog. | |
1736 | */ | |
1737 | if (k_hasafs()) { /* Do we have AFS? */ | |
1738 | ||
1739 | aklog_path = xstrdup(KPROGDIR); | |
1740 | ||
1741 | /* | |
1742 | * Make sure it exists before we try to run it | |
1743 | */ | |
1744 | if (stat(aklog_path, &st) == 0) { | |
1745 | debug("Running %s to get afs token.",aklog_path); | |
1746 | system(aklog_path); | |
1747 | } else { | |
1748 | debug("%s does not exist.",aklog_path); | |
1749 | } | |
1750 | ||
1751 | xfree(aklog_path); | |
1752 | } | |
1753 | #endif /* AFS_KRB5 */ | |
1754 | ||
75be3237 | 1755 | #ifdef SESSION_HOOKS |
1756 | if (options.session_hooks_allow && | |
1757 | options.session_hooks_startup_cmd) | |
1758 | { | |
1759 | execute_session_hook(options.session_hooks_startup_cmd, | |
1760 | s->authctxt, | |
1761 | /* startup = */ 1, | |
1762 | options.session_hooks_shutdown_cmd != NULL); | |
1763 | } | |
1764 | #endif | |
3c0ef626 | 1765 | |
08822d99 | 1766 | /* Change current directory to the user's home directory. */ |
3c0ef626 | 1767 | if (chdir(pw->pw_dir) < 0) { |
1768 | fprintf(stderr, "Could not chdir to home directory %s: %s\n", | |
1769 | pw->pw_dir, strerror(errno)); | |
1770 | #ifdef HAVE_LOGIN_CAP | |
1771 | if (login_getcapbool(lc, "requirehome", 0)) | |
1772 | exit(1); | |
1773 | #endif | |
1774 | } | |
1775 | ||
e9702f7d | 1776 | if (!options.use_login) |
1777 | do_rc_files(s, shell); | |
3c0ef626 | 1778 | |
1779 | /* restore SIGPIPE for child */ | |
1780 | signal(SIGPIPE, SIG_DFL); | |
1781 | ||
e9702f7d | 1782 | if (options.use_login) { |
350391c5 | 1783 | launch_login(pw, hostname); |
1784 | /* NEVERREACHED */ | |
e9702f7d | 1785 | } |
1786 | ||
1787 | /* Get the last component of the shell name. */ | |
1788 | if ((shell0 = strrchr(shell, '/')) != NULL) | |
1789 | shell0++; | |
1790 | else | |
1791 | shell0 = shell; | |
1792 | ||
3c0ef626 | 1793 | /* |
1794 | * If we have no command, execute the shell. In this case, the shell | |
1795 | * name to be passed in argv[0] is preceded by '-' to indicate that | |
1796 | * this is a login shell. | |
1797 | */ | |
1798 | if (!command) { | |
e9702f7d | 1799 | char argv0[256]; |
3c0ef626 | 1800 | |
e9702f7d | 1801 | /* Start the shell. Set initial character to '-'. */ |
1802 | argv0[0] = '-'; | |
3c0ef626 | 1803 | |
e9702f7d | 1804 | if (strlcpy(argv0 + 1, shell0, sizeof(argv0) - 1) |
1805 | >= sizeof(argv0) - 1) { | |
1806 | errno = EINVAL; | |
3c0ef626 | 1807 | perror(shell); |
1808 | exit(1); | |
e9702f7d | 1809 | } |
3c0ef626 | 1810 | |
e9702f7d | 1811 | /* Execute the shell. */ |
1812 | argv[0] = argv0; | |
1813 | argv[1] = NULL; | |
5ab1e3bd | 1814 | execve(shell, argv, environ); |
3c0ef626 | 1815 | |
e9702f7d | 1816 | /* Executing the shell failed. */ |
1817 | perror(shell); | |
1818 | exit(1); | |
3c0ef626 | 1819 | } |
1820 | /* | |
1821 | * Execute the command using the user's shell. This uses the -c | |
1822 | * option to execute the command. | |
1823 | */ | |
e9702f7d | 1824 | argv[0] = (char *) shell0; |
3c0ef626 | 1825 | argv[1] = "-c"; |
1826 | argv[2] = (char *) command; | |
1827 | argv[3] = NULL; | |
5ab1e3bd | 1828 | execve(shell, argv, environ); |
3c0ef626 | 1829 | perror(shell); |
1830 | exit(1); | |
1831 | } | |
1832 | ||
1833 | Session * | |
1834 | session_new(void) | |
1835 | { | |
1836 | int i; | |
1837 | static int did_init = 0; | |
1838 | if (!did_init) { | |
1839 | debug("session_new: init"); | |
e9702f7d | 1840 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1841 | sessions[i].used = 0; |
1842 | } | |
1843 | did_init = 1; | |
1844 | } | |
e9702f7d | 1845 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1846 | Session *s = &sessions[i]; |
1847 | if (! s->used) { | |
1848 | memset(s, 0, sizeof(*s)); | |
1849 | s->chanid = -1; | |
1850 | s->ptyfd = -1; | |
1851 | s->ttyfd = -1; | |
1852 | s->used = 1; | |
1853 | s->self = i; | |
2ce0bfe4 | 1854 | s->x11_chanids = NULL; |
3c0ef626 | 1855 | debug("session_new: session %d", i); |
1856 | return s; | |
1857 | } | |
1858 | } | |
1859 | return NULL; | |
1860 | } | |
1861 | ||
1862 | static void | |
1863 | session_dump(void) | |
1864 | { | |
1865 | int i; | |
e9702f7d | 1866 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1867 | Session *s = &sessions[i]; |
44a053a3 | 1868 | debug("dump: used %d session %d %p channel %d pid %ld", |
3c0ef626 | 1869 | s->used, |
1870 | s->self, | |
1871 | s, | |
1872 | s->chanid, | |
44a053a3 | 1873 | (long)s->pid); |
3c0ef626 | 1874 | } |
1875 | } | |
1876 | ||
1877 | int | |
1878 | session_open(Authctxt *authctxt, int chanid) | |
1879 | { | |
1880 | Session *s = session_new(); | |
1881 | debug("session_open: channel %d", chanid); | |
1882 | if (s == NULL) { | |
1883 | error("no more sessions"); | |
1884 | return 0; | |
1885 | } | |
1886 | s->authctxt = authctxt; | |
1887 | s->pw = authctxt->pw; | |
540d72c3 | 1888 | if (s->pw == NULL || !authctxt->valid) |
3c0ef626 | 1889 | fatal("no user for session %d", s->self); |
1890 | debug("session_open: session %d: link with channel %d", s->self, chanid); | |
1891 | s->chanid = chanid; | |
1892 | return 1; | |
1893 | } | |
1894 | ||
350391c5 | 1895 | Session * |
1896 | session_by_tty(char *tty) | |
1897 | { | |
1898 | int i; | |
1899 | for (i = 0; i < MAX_SESSIONS; i++) { | |
1900 | Session *s = &sessions[i]; | |
1901 | if (s->used && s->ttyfd != -1 && strcmp(s->tty, tty) == 0) { | |
1902 | debug("session_by_tty: session %d tty %s", i, tty); | |
1903 | return s; | |
1904 | } | |
1905 | } | |
1906 | debug("session_by_tty: unknown tty %.100s", tty); | |
1907 | session_dump(); | |
1908 | return NULL; | |
1909 | } | |
1910 | ||
3c0ef626 | 1911 | static Session * |
1912 | session_by_channel(int id) | |
1913 | { | |
1914 | int i; | |
e9702f7d | 1915 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1916 | Session *s = &sessions[i]; |
1917 | if (s->used && s->chanid == id) { | |
1918 | debug("session_by_channel: session %d channel %d", i, id); | |
1919 | return s; | |
1920 | } | |
1921 | } | |
1922 | debug("session_by_channel: unknown channel %d", id); | |
1923 | session_dump(); | |
1924 | return NULL; | |
1925 | } | |
1926 | ||
2ce0bfe4 | 1927 | static Session * |
1928 | session_by_x11_channel(int id) | |
1929 | { | |
1930 | int i, j; | |
1931 | ||
1932 | for (i = 0; i < MAX_SESSIONS; i++) { | |
1933 | Session *s = &sessions[i]; | |
1934 | ||
1935 | if (s->x11_chanids == NULL || !s->used) | |
1936 | continue; | |
1937 | for (j = 0; s->x11_chanids[j] != -1; j++) { | |
1938 | if (s->x11_chanids[j] == id) { | |
1939 | debug("session_by_x11_channel: session %d " | |
1940 | "channel %d", s->self, id); | |
1941 | return s; | |
1942 | } | |
1943 | } | |
1944 | } | |
1945 | debug("session_by_x11_channel: unknown channel %d", id); | |
1946 | session_dump(); | |
1947 | return NULL; | |
1948 | } | |
1949 | ||
3c0ef626 | 1950 | static Session * |
1951 | session_by_pid(pid_t pid) | |
1952 | { | |
1953 | int i; | |
44a053a3 | 1954 | debug("session_by_pid: pid %ld", (long)pid); |
e9702f7d | 1955 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1956 | Session *s = &sessions[i]; |
1957 | if (s->used && s->pid == pid) | |
1958 | return s; | |
1959 | } | |
44a053a3 | 1960 | error("session_by_pid: unknown pid %ld", (long)pid); |
3c0ef626 | 1961 | session_dump(); |
1962 | return NULL; | |
1963 | } | |
1964 | ||
1965 | static int | |
1966 | session_window_change_req(Session *s) | |
1967 | { | |
1968 | s->col = packet_get_int(); | |
1969 | s->row = packet_get_int(); | |
1970 | s->xpixel = packet_get_int(); | |
1971 | s->ypixel = packet_get_int(); | |
e9702f7d | 1972 | packet_check_eom(); |
3c0ef626 | 1973 | pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel); |
1974 | return 1; | |
1975 | } | |
1976 | ||
1977 | static int | |
1978 | session_pty_req(Session *s) | |
1979 | { | |
1980 | u_int len; | |
1981 | int n_bytes; | |
1982 | ||
1983 | if (no_pty_flag) { | |
1984 | debug("Allocating a pty not permitted for this authentication."); | |
1985 | return 0; | |
1986 | } | |
1987 | if (s->ttyfd != -1) { | |
1988 | packet_disconnect("Protocol error: you already have a pty."); | |
1989 | return 0; | |
1990 | } | |
1991 | ||
1992 | s->term = packet_get_string(&len); | |
1993 | ||
1994 | if (compat20) { | |
1995 | s->col = packet_get_int(); | |
1996 | s->row = packet_get_int(); | |
1997 | } else { | |
1998 | s->row = packet_get_int(); | |
1999 | s->col = packet_get_int(); | |
2000 | } | |
2001 | s->xpixel = packet_get_int(); | |
2002 | s->ypixel = packet_get_int(); | |
2003 | ||
2004 | if (strcmp(s->term, "") == 0) { | |
2005 | xfree(s->term); | |
2006 | s->term = NULL; | |
2007 | } | |
2008 | ||
2009 | /* Allocate a pty and open it. */ | |
2010 | debug("Allocating pty."); | |
350391c5 | 2011 | if (!PRIVSEP(pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty)))) { |
3c0ef626 | 2012 | if (s->term) |
2013 | xfree(s->term); | |
2014 | s->term = NULL; | |
2015 | s->ptyfd = -1; | |
2016 | s->ttyfd = -1; | |
2017 | error("session_pty_req: session %d alloc failed", s->self); | |
2018 | return 0; | |
2019 | } | |
2020 | debug("session_pty_req: session %d alloc %s", s->self, s->tty); | |
2021 | ||
2022 | /* for SSH1 the tty modes length is not given */ | |
2023 | if (!compat20) | |
2024 | n_bytes = packet_remaining(); | |
2025 | tty_parse_modes(s->ttyfd, &n_bytes); | |
2026 | ||
350391c5 | 2027 | if (!use_privsep) |
2028 | pty_setowner(s->pw, s->tty); | |
3c0ef626 | 2029 | |
2030 | /* Set window size from the packet. */ | |
2031 | pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel); | |
2032 | ||
e9702f7d | 2033 | packet_check_eom(); |
3c0ef626 | 2034 | session_proctitle(s); |
2035 | return 1; | |
2036 | } | |
2037 | ||
2038 | static int | |
2039 | session_subsystem_req(Session *s) | |
2040 | { | |
2041 | struct stat st; | |
2042 | u_int len; | |
2043 | int success = 0; | |
2044 | char *cmd, *subsys = packet_get_string(&len); | |
2ce0bfe4 | 2045 | u_int i; |
3c0ef626 | 2046 | |
e9702f7d | 2047 | packet_check_eom(); |
7cac2b65 | 2048 | logit("subsystem request for %.100s", subsys); |
3c0ef626 | 2049 | |
2050 | for (i = 0; i < options.num_subsystems; i++) { | |
2051 | if (strcmp(subsys, options.subsystem_name[i]) == 0) { | |
2052 | cmd = options.subsystem_command[i]; | |
2053 | if (stat(cmd, &st) < 0) { | |
2054 | error("subsystem: cannot stat %s: %s", cmd, | |
2055 | strerror(errno)); | |
2056 | break; | |
2057 | } | |
2058 | debug("subsystem: exec() %s", cmd); | |
2059 | s->is_subsystem = 1; | |
2060 | do_exec(s, cmd); | |
2061 | success = 1; | |
e9702f7d | 2062 | break; |
3c0ef626 | 2063 | } |
2064 | } | |
2065 | ||
2066 | if (!success) | |
7cac2b65 | 2067 | logit("subsystem request for %.100s failed, subsystem not found", |
3c0ef626 | 2068 | subsys); |
2069 | ||
2070 | xfree(subsys); | |
2071 | return success; | |
2072 | } | |
2073 | ||
2074 | static int | |
2075 | session_x11_req(Session *s) | |
2076 | { | |
2077 | int success; | |
2078 | ||
2ce0bfe4 | 2079 | if (s->auth_proto != NULL || s->auth_data != NULL) { |
2080 | error("session_x11_req: session %d: " | |
08822d99 | 2081 | "x11 forwarding already active", s->self); |
2ce0bfe4 | 2082 | return 0; |
2083 | } | |
3c0ef626 | 2084 | s->single_connection = packet_get_char(); |
2085 | s->auth_proto = packet_get_string(NULL); | |
2086 | s->auth_data = packet_get_string(NULL); | |
2087 | s->screen = packet_get_int(); | |
e9702f7d | 2088 | packet_check_eom(); |
3c0ef626 | 2089 | |
2090 | success = session_setup_x11fwd(s); | |
2091 | if (!success) { | |
2092 | xfree(s->auth_proto); | |
2093 | xfree(s->auth_data); | |
2094 | s->auth_proto = NULL; | |
2095 | s->auth_data = NULL; | |
2096 | } | |
2097 | return success; | |
2098 | } | |
2099 | ||
2100 | static int | |
2101 | session_shell_req(Session *s) | |
2102 | { | |
e9702f7d | 2103 | packet_check_eom(); |
3c0ef626 | 2104 | do_exec(s, NULL); |
2105 | return 1; | |
2106 | } | |
2107 | ||
2108 | static int | |
2109 | session_exec_req(Session *s) | |
2110 | { | |
2111 | u_int len; | |
2112 | char *command = packet_get_string(&len); | |
e9702f7d | 2113 | packet_check_eom(); |
3c0ef626 | 2114 | do_exec(s, command); |
2115 | xfree(command); | |
2116 | return 1; | |
2117 | } | |
2118 | ||
7cac2b65 | 2119 | static int |
2120 | session_break_req(Session *s) | |
2121 | { | |
7cac2b65 | 2122 | |
7e82606e | 2123 | packet_get_int(); /* ignored */ |
7cac2b65 | 2124 | packet_check_eom(); |
2125 | ||
2126 | if (s->ttyfd == -1 || | |
2127 | tcsendbreak(s->ttyfd, 0) < 0) | |
2128 | return 0; | |
2129 | return 1; | |
2130 | } | |
2131 | ||
7e82606e | 2132 | static int |
2133 | session_env_req(Session *s) | |
2134 | { | |
2135 | char *name, *val; | |
2136 | u_int name_len, val_len, i; | |
2137 | ||
2138 | name = packet_get_string(&name_len); | |
2139 | val = packet_get_string(&val_len); | |
2140 | packet_check_eom(); | |
2141 | ||
2142 | /* Don't set too many environment variables */ | |
2143 | if (s->num_env > 128) { | |
2144 | debug2("Ignoring env request %s: too many env vars", name); | |
2145 | goto fail; | |
2146 | } | |
2147 | ||
2148 | for (i = 0; i < options.num_accept_env; i++) { | |
2149 | if (match_pattern(name, options.accept_env[i])) { | |
2150 | debug2("Setting env %d: %s=%s", s->num_env, name, val); | |
2151 | s->env = xrealloc(s->env, sizeof(*s->env) * | |
2152 | (s->num_env + 1)); | |
2153 | s->env[s->num_env].name = name; | |
2154 | s->env[s->num_env].val = val; | |
2155 | s->num_env++; | |
2156 | return (1); | |
2157 | } | |
2158 | } | |
2159 | debug2("Ignoring env request %s: disallowed name", name); | |
2160 | ||
2161 | fail: | |
2162 | xfree(name); | |
2163 | xfree(val); | |
2164 | return (0); | |
2165 | } | |
2166 | ||
3c0ef626 | 2167 | static int |
2168 | session_auth_agent_req(Session *s) | |
2169 | { | |
2170 | static int called = 0; | |
e9702f7d | 2171 | packet_check_eom(); |
3c0ef626 | 2172 | if (no_agent_forwarding_flag) { |
2173 | debug("session_auth_agent_req: no_agent_forwarding_flag"); | |
2174 | return 0; | |
2175 | } | |
2176 | if (called) { | |
2177 | return 0; | |
2178 | } else { | |
2179 | called = 1; | |
2180 | return auth_input_request_forwarding(s->pw); | |
2181 | } | |
2182 | } | |
2183 | ||
e9702f7d | 2184 | int |
2185 | session_input_channel_req(Channel *c, const char *rtype) | |
3c0ef626 | 2186 | { |
3c0ef626 | 2187 | int success = 0; |
3c0ef626 | 2188 | Session *s; |
3c0ef626 | 2189 | |
e9702f7d | 2190 | if ((s = session_by_channel(c->self)) == NULL) { |
7cac2b65 | 2191 | logit("session_input_channel_req: no session %d req %.100s", |
e9702f7d | 2192 | c->self, rtype); |
2193 | return 0; | |
2194 | } | |
2195 | debug("session_input_channel_req: session %d req %s", s->self, rtype); | |
3c0ef626 | 2196 | |
2197 | /* | |
2198 | * a session is in LARVAL state until a shell, a command | |
2199 | * or a subsystem is executed | |
2200 | */ | |
2201 | if (c->type == SSH_CHANNEL_LARVAL) { | |
2202 | if (strcmp(rtype, "shell") == 0) { | |
2203 | success = session_shell_req(s); | |
2204 | } else if (strcmp(rtype, "exec") == 0) { | |
2205 | success = session_exec_req(s); | |
2206 | } else if (strcmp(rtype, "pty-req") == 0) { | |
2207 | success = session_pty_req(s); | |
2208 | } else if (strcmp(rtype, "x11-req") == 0) { | |
2209 | success = session_x11_req(s); | |
2210 | } else if (strcmp(rtype, "auth-agent-req@openssh.com") == 0) { | |
2211 | success = session_auth_agent_req(s); | |
2212 | } else if (strcmp(rtype, "subsystem") == 0) { | |
2213 | success = session_subsystem_req(s); | |
7e82606e | 2214 | } else if (strcmp(rtype, "env") == 0) { |
2215 | success = session_env_req(s); | |
3c0ef626 | 2216 | } |
2217 | } | |
2218 | if (strcmp(rtype, "window-change") == 0) { | |
2219 | success = session_window_change_req(s); | |
7e82606e | 2220 | } else if (strcmp(rtype, "break") == 0) { |
2221 | success = session_break_req(s); | |
3c0ef626 | 2222 | } |
7e82606e | 2223 | |
e9702f7d | 2224 | return success; |
3c0ef626 | 2225 | } |
2226 | ||
2227 | void | |
2228 | session_set_fds(Session *s, int fdin, int fdout, int fderr) | |
2229 | { | |
2230 | if (!compat20) | |
2231 | fatal("session_set_fds: called for proto != 2.0"); | |
2232 | /* | |
2233 | * now that have a child and a pipe to the child, | |
2234 | * we can activate our channel and register the fd's | |
2235 | */ | |
2236 | if (s->chanid == -1) | |
2237 | fatal("no channel for session %d", s->self); | |
a7213e65 | 2238 | if(options.hpn_disabled) |
2239 | channel_set_fds(s->chanid, | |
2240 | fdout, fdin, fderr, | |
2241 | fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ, | |
2242 | 1, | |
2243 | CHAN_SES_WINDOW_DEFAULT); | |
2244 | else | |
2245 | channel_set_fds(s->chanid, | |
2246 | fdout, fdin, fderr, | |
2247 | fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ, | |
2248 | 1, | |
2249 | options.hpn_buffer_size); | |
3c0ef626 | 2250 | } |
2251 | ||
2252 | /* | |
2253 | * Function to perform pty cleanup. Also called if we get aborted abnormally | |
2254 | * (e.g., due to a dropped connection). | |
2255 | */ | |
350391c5 | 2256 | void |
540d72c3 | 2257 | session_pty_cleanup2(Session *s) |
3c0ef626 | 2258 | { |
3c0ef626 | 2259 | if (s == NULL) { |
2260 | error("session_pty_cleanup: no session"); | |
2261 | return; | |
2262 | } | |
2263 | if (s->ttyfd == -1) | |
2264 | return; | |
2265 | ||
2266 | debug("session_pty_cleanup: session %d release %s", s->self, s->tty); | |
2267 | ||
2268 | /* Record that the user has logged out. */ | |
2269 | if (s->pid != 0) | |
e9702f7d | 2270 | record_logout(s->pid, s->tty, s->pw->pw_name); |
3c0ef626 | 2271 | |
2272 | /* Release the pseudo-tty. */ | |
350391c5 | 2273 | if (getuid() == 0) |
2274 | pty_release(s->tty); | |
3c0ef626 | 2275 | |
2276 | /* | |
2277 | * Close the server side of the socket pairs. We must do this after | |
2278 | * the pty cleanup, so that another process doesn't get this pty | |
2279 | * while we're still cleaning up. | |
2280 | */ | |
2281 | if (close(s->ptymaster) < 0) | |
350391c5 | 2282 | error("close(s->ptymaster/%d): %s", s->ptymaster, strerror(errno)); |
3c0ef626 | 2283 | |
2284 | /* unlink pty from session */ | |
2285 | s->ttyfd = -1; | |
2286 | } | |
2287 | ||
350391c5 | 2288 | void |
540d72c3 | 2289 | session_pty_cleanup(Session *s) |
350391c5 | 2290 | { |
540d72c3 | 2291 | PRIVSEP(session_pty_cleanup2(s)); |
350391c5 | 2292 | } |
2293 | ||
d03f4262 | 2294 | static char * |
2295 | sig2name(int sig) | |
2296 | { | |
2297 | #define SSH_SIG(x) if (sig == SIG ## x) return #x | |
2298 | SSH_SIG(ABRT); | |
2299 | SSH_SIG(ALRM); | |
2300 | SSH_SIG(FPE); | |
2301 | SSH_SIG(HUP); | |
2302 | SSH_SIG(ILL); | |
2303 | SSH_SIG(INT); | |
2304 | SSH_SIG(KILL); | |
2305 | SSH_SIG(PIPE); | |
2306 | SSH_SIG(QUIT); | |
2307 | SSH_SIG(SEGV); | |
2308 | SSH_SIG(TERM); | |
2309 | SSH_SIG(USR1); | |
2310 | SSH_SIG(USR2); | |
2311 | #undef SSH_SIG | |
2312 | return "SIG@openssh.com"; | |
2313 | } | |
2314 | ||
2ce0bfe4 | 2315 | static void |
2316 | session_close_x11(int id) | |
2317 | { | |
2318 | Channel *c; | |
2319 | ||
08822d99 | 2320 | if ((c = channel_by_id(id)) == NULL) { |
2ce0bfe4 | 2321 | debug("session_close_x11: x11 channel %d missing", id); |
2322 | } else { | |
2323 | /* Detach X11 listener */ | |
2324 | debug("session_close_x11: detach x11 channel %d", id); | |
2325 | channel_cancel_cleanup(id); | |
2326 | if (c->ostate != CHAN_OUTPUT_CLOSED) | |
2327 | chan_mark_dead(c); | |
2328 | } | |
2329 | } | |
2330 | ||
2331 | static void | |
2332 | session_close_single_x11(int id, void *arg) | |
2333 | { | |
2334 | Session *s; | |
2335 | u_int i; | |
2336 | ||
2337 | debug3("session_close_single_x11: channel %d", id); | |
2338 | channel_cancel_cleanup(id); | |
2339 | if ((s = session_by_x11_channel(id)) == NULL) | |
2340 | fatal("session_close_single_x11: no x11 channel %d", id); | |
2341 | for (i = 0; s->x11_chanids[i] != -1; i++) { | |
2342 | debug("session_close_single_x11: session %d: " | |
2343 | "closing channel %d", s->self, s->x11_chanids[i]); | |
2344 | /* | |
2345 | * The channel "id" is already closing, but make sure we | |
2346 | * close all of its siblings. | |
2347 | */ | |
2348 | if (s->x11_chanids[i] != id) | |
2349 | session_close_x11(s->x11_chanids[i]); | |
2350 | } | |
2351 | xfree(s->x11_chanids); | |
2352 | s->x11_chanids = NULL; | |
2353 | if (s->display) { | |
2354 | xfree(s->display); | |
2355 | s->display = NULL; | |
2356 | } | |
2357 | if (s->auth_proto) { | |
2358 | xfree(s->auth_proto); | |
2359 | s->auth_proto = NULL; | |
2360 | } | |
2361 | if (s->auth_data) { | |
2362 | xfree(s->auth_data); | |
2363 | s->auth_data = NULL; | |
2364 | } | |
2365 | if (s->auth_display) { | |
2366 | xfree(s->auth_display); | |
2367 | s->auth_display = NULL; | |
2368 | } | |
2369 | } | |
2370 | ||
3c0ef626 | 2371 | static void |
2372 | session_exit_message(Session *s, int status) | |
2373 | { | |
2374 | Channel *c; | |
e9702f7d | 2375 | |
2376 | if ((c = channel_lookup(s->chanid)) == NULL) | |
3c0ef626 | 2377 | fatal("session_exit_message: session %d: no channel %d", |
2378 | s->self, s->chanid); | |
44a053a3 | 2379 | debug("session_exit_message: session %d channel %d pid %ld", |
2380 | s->self, s->chanid, (long)s->pid); | |
3c0ef626 | 2381 | |
2382 | if (WIFEXITED(status)) { | |
e9702f7d | 2383 | channel_request_start(s->chanid, "exit-status", 0); |
3c0ef626 | 2384 | packet_put_int(WEXITSTATUS(status)); |
2385 | packet_send(); | |
2386 | } else if (WIFSIGNALED(status)) { | |
e9702f7d | 2387 | channel_request_start(s->chanid, "exit-signal", 0); |
d03f4262 | 2388 | packet_put_cstring(sig2name(WTERMSIG(status))); |
3c0ef626 | 2389 | #ifdef WCOREDUMP |
2390 | packet_put_char(WCOREDUMP(status)); | |
2391 | #else /* WCOREDUMP */ | |
2392 | packet_put_char(0); | |
2393 | #endif /* WCOREDUMP */ | |
2394 | packet_put_cstring(""); | |
2395 | packet_put_cstring(""); | |
2396 | packet_send(); | |
2397 | } else { | |
2398 | /* Some weird exit cause. Just exit. */ | |
2399 | packet_disconnect("wait returned status %04x.", status); | |
2400 | } | |
2401 | ||
2402 | /* disconnect channel */ | |
2403 | debug("session_exit_message: release channel %d", s->chanid); | |
08822d99 | 2404 | |
2405 | /* | |
2406 | * Adjust cleanup callback attachment to send close messages when | |
2407 | * the channel gets EOF. The session will be then be closed | |
2408 | * by session_close_by_channel when the childs close their fds. | |
2409 | */ | |
2410 | channel_register_cleanup(c->self, session_close_by_channel, 1); | |
2411 | ||
3c0ef626 | 2412 | /* |
2413 | * emulate a write failure with 'chan_write_failed', nobody will be | |
2414 | * interested in data we write. | |
2415 | * Note that we must not call 'chan_read_failed', since there could | |
2416 | * be some more data waiting in the pipe. | |
2417 | */ | |
2418 | if (c->ostate != CHAN_OUTPUT_CLOSED) | |
2419 | chan_write_failed(c); | |
3c0ef626 | 2420 | } |
2421 | ||
350391c5 | 2422 | void |
3c0ef626 | 2423 | session_close(Session *s) |
2424 | { | |
2ce0bfe4 | 2425 | u_int i; |
7e82606e | 2426 | |
44a053a3 | 2427 | debug("session_close: session %d pid %ld", s->self, (long)s->pid); |
540d72c3 | 2428 | if (s->ttyfd != -1) |
3c0ef626 | 2429 | session_pty_cleanup(s); |
3c0ef626 | 2430 | if (s->term) |
2431 | xfree(s->term); | |
2432 | if (s->display) | |
2433 | xfree(s->display); | |
2ce0bfe4 | 2434 | if (s->x11_chanids) |
2435 | xfree(s->x11_chanids); | |
e9702f7d | 2436 | if (s->auth_display) |
2437 | xfree(s->auth_display); | |
3c0ef626 | 2438 | if (s->auth_data) |
2439 | xfree(s->auth_data); | |
2440 | if (s->auth_proto) | |
2441 | xfree(s->auth_proto); | |
2442 | s->used = 0; | |
7e82606e | 2443 | for (i = 0; i < s->num_env; i++) { |
2444 | xfree(s->env[i].name); | |
2445 | xfree(s->env[i].val); | |
2446 | } | |
2447 | if (s->env != NULL) | |
2448 | xfree(s->env); | |
3c0ef626 | 2449 | session_proctitle(s); |
2450 | } | |
2451 | ||
2452 | void | |
2453 | session_close_by_pid(pid_t pid, int status) | |
2454 | { | |
2455 | Session *s = session_by_pid(pid); | |
2456 | if (s == NULL) { | |
44a053a3 | 2457 | debug("session_close_by_pid: no session for pid %ld", |
2458 | (long)pid); | |
3c0ef626 | 2459 | return; |
2460 | } | |
2461 | if (s->chanid != -1) | |
2462 | session_exit_message(s, status); | |
08822d99 | 2463 | if (s->ttyfd != -1) |
2464 | session_pty_cleanup(s); | |
4b6dae8f | 2465 | s->pid = 0; |
3c0ef626 | 2466 | } |
2467 | ||
2468 | /* | |
2469 | * this is called when a channel dies before | |
2470 | * the session 'child' itself dies | |
2471 | */ | |
2472 | void | |
2473 | session_close_by_channel(int id, void *arg) | |
2474 | { | |
2475 | Session *s = session_by_channel(id); | |
08822d99 | 2476 | u_int i; |
2ce0bfe4 | 2477 | |
3c0ef626 | 2478 | if (s == NULL) { |
2479 | debug("session_close_by_channel: no session for id %d", id); | |
2480 | return; | |
2481 | } | |
44a053a3 | 2482 | debug("session_close_by_channel: channel %d child %ld", |
2483 | id, (long)s->pid); | |
3c0ef626 | 2484 | if (s->pid != 0) { |
2485 | debug("session_close_by_channel: channel %d: has child", id); | |
2486 | /* | |
2487 | * delay detach of session, but release pty, since | |
2488 | * the fd's to the child are already closed | |
2489 | */ | |
540d72c3 | 2490 | if (s->ttyfd != -1) |
3c0ef626 | 2491 | session_pty_cleanup(s); |
3c0ef626 | 2492 | return; |
2493 | } | |
2494 | /* detach by removing callback */ | |
2495 | channel_cancel_cleanup(s->chanid); | |
08822d99 | 2496 | |
2497 | /* Close any X11 listeners associated with this session */ | |
2498 | if (s->x11_chanids != NULL) { | |
2499 | for (i = 0; s->x11_chanids[i] != -1; i++) { | |
2500 | session_close_x11(s->x11_chanids[i]); | |
2501 | s->x11_chanids[i] = -1; | |
2502 | } | |
2503 | } | |
2504 | ||
3c0ef626 | 2505 | s->chanid = -1; |
2506 | session_close(s); | |
2507 | } | |
2508 | ||
2509 | void | |
350391c5 | 2510 | session_destroy_all(void (*closefunc)(Session *)) |
3c0ef626 | 2511 | { |
2512 | int i; | |
e9702f7d | 2513 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 2514 | Session *s = &sessions[i]; |
350391c5 | 2515 | if (s->used) { |
2516 | if (closefunc != NULL) | |
2517 | closefunc(s); | |
2518 | else | |
2519 | session_close(s); | |
2520 | } | |
3c0ef626 | 2521 | } |
2522 | } | |
2523 | ||
2524 | static char * | |
2525 | session_tty_list(void) | |
2526 | { | |
2527 | static char buf[1024]; | |
2528 | int i; | |
bfe49944 | 2529 | char *cp; |
2530 | ||
3c0ef626 | 2531 | buf[0] = '\0'; |
e9702f7d | 2532 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 2533 | Session *s = &sessions[i]; |
2534 | if (s->used && s->ttyfd != -1) { | |
540d72c3 | 2535 | |
bfe49944 | 2536 | if (strncmp(s->tty, "/dev/", 5) != 0) { |
2537 | cp = strrchr(s->tty, '/'); | |
2538 | cp = (cp == NULL) ? s->tty : cp + 1; | |
2539 | } else | |
2540 | cp = s->tty + 5; | |
540d72c3 | 2541 | |
3c0ef626 | 2542 | if (buf[0] != '\0') |
2543 | strlcat(buf, ",", sizeof buf); | |
bfe49944 | 2544 | strlcat(buf, cp, sizeof buf); |
3c0ef626 | 2545 | } |
2546 | } | |
2547 | if (buf[0] == '\0') | |
2548 | strlcpy(buf, "notty", sizeof buf); | |
2549 | return buf; | |
2550 | } | |
2551 | ||
2552 | void | |
2553 | session_proctitle(Session *s) | |
2554 | { | |
2555 | if (s->pw == NULL) | |
2556 | error("no user for session %d", s->self); | |
2557 | else | |
2558 | setproctitle("%s@%s", s->pw->pw_name, session_tty_list()); | |
2559 | } | |
2560 | ||
2561 | int | |
2562 | session_setup_x11fwd(Session *s) | |
2563 | { | |
2564 | struct stat st; | |
e9702f7d | 2565 | char display[512], auth_display[512]; |
2566 | char hostname[MAXHOSTNAMELEN]; | |
2ce0bfe4 | 2567 | u_int i; |
3c0ef626 | 2568 | |
2569 | if (no_x11_forwarding_flag) { | |
2570 | packet_send_debug("X11 forwarding disabled in user configuration file."); | |
2571 | return 0; | |
2572 | } | |
2573 | if (!options.x11_forwarding) { | |
2574 | debug("X11 forwarding disabled in server configuration file."); | |
2575 | return 0; | |
2576 | } | |
2577 | if (!options.xauth_location || | |
2578 | (stat(options.xauth_location, &st) == -1)) { | |
2579 | packet_send_debug("No xauth program; cannot forward with spoofing."); | |
2580 | return 0; | |
2581 | } | |
2582 | if (options.use_login) { | |
2583 | packet_send_debug("X11 forwarding disabled; " | |
2584 | "not compatible with UseLogin=yes."); | |
2585 | return 0; | |
2586 | } | |
2587 | if (s->display != NULL) { | |
2588 | debug("X11 display already set."); | |
2589 | return 0; | |
2590 | } | |
276b07a3 | 2591 | if (x11_create_display_inet(options.x11_display_offset, |
2592 | options.x11_use_localhost, s->single_connection, | |
a7213e65 | 2593 | &s->display_number, &s->x11_chanids, |
2594 | options.hpn_disabled, options.hpn_buffer_size) == -1) { | |
3c0ef626 | 2595 | debug("x11_create_display_inet failed."); |
2596 | return 0; | |
2597 | } | |
2ce0bfe4 | 2598 | for (i = 0; s->x11_chanids[i] != -1; i++) { |
2599 | channel_register_cleanup(s->x11_chanids[i], | |
08822d99 | 2600 | session_close_single_x11, 0); |
2ce0bfe4 | 2601 | } |
e9702f7d | 2602 | |
2603 | /* Set up a suitable value for the DISPLAY variable. */ | |
2604 | if (gethostname(hostname, sizeof(hostname)) < 0) | |
2605 | fatal("gethostname: %.100s", strerror(errno)); | |
2606 | /* | |
2607 | * auth_display must be used as the displayname when the | |
2608 | * authorization entry is added with xauth(1). This will be | |
2609 | * different than the DISPLAY string for localhost displays. | |
2610 | */ | |
2611 | if (options.x11_use_localhost) { | |
276b07a3 | 2612 | snprintf(display, sizeof display, "localhost:%u.%u", |
e9702f7d | 2613 | s->display_number, s->screen); |
276b07a3 | 2614 | snprintf(auth_display, sizeof auth_display, "unix:%u.%u", |
e9702f7d | 2615 | s->display_number, s->screen); |
2616 | s->display = xstrdup(display); | |
2617 | s->auth_display = xstrdup(auth_display); | |
2618 | } else { | |
2619 | #ifdef IPADDR_IN_DISPLAY | |
2620 | struct hostent *he; | |
2621 | struct in_addr my_addr; | |
2622 | ||
2623 | he = gethostbyname(hostname); | |
2624 | if (he == NULL) { | |
2625 | error("Can't get IP address for X11 DISPLAY."); | |
2626 | packet_send_debug("Can't get IP address for X11 DISPLAY."); | |
2627 | return 0; | |
2628 | } | |
2629 | memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr)); | |
276b07a3 | 2630 | snprintf(display, sizeof display, "%.50s:%u.%u", inet_ntoa(my_addr), |
e9702f7d | 2631 | s->display_number, s->screen); |
2632 | #else | |
276b07a3 | 2633 | snprintf(display, sizeof display, "%.400s:%u.%u", hostname, |
e9702f7d | 2634 | s->display_number, s->screen); |
2635 | #endif | |
2636 | s->display = xstrdup(display); | |
2637 | s->auth_display = xstrdup(display); | |
2638 | } | |
2639 | ||
3c0ef626 | 2640 | return 1; |
2641 | } | |
2642 | ||
2643 | static void | |
2644 | do_authenticated2(Authctxt *authctxt) | |
2645 | { | |
2646 | server_loop2(authctxt); | |
540d72c3 | 2647 | } |
2648 | ||
2649 | void | |
2650 | do_cleanup(Authctxt *authctxt) | |
2651 | { | |
2652 | static int called = 0; | |
2653 | ||
2654 | debug("do_cleanup"); | |
2655 | ||
2656 | /* no cleanup if we're in the child for login shell */ | |
2657 | if (is_child) | |
2658 | return; | |
2659 | ||
2660 | /* avoid double cleanup */ | |
2661 | if (called) | |
2662 | return; | |
2663 | called = 1; | |
2664 | ||
2665 | if (authctxt == NULL) | |
2666 | return; | |
2667 | #ifdef KRB5 | |
2668 | if (options.kerberos_ticket_cleanup && | |
2669 | authctxt->krb5_ctx) | |
2670 | krb5_cleanup_proc(authctxt); | |
5598e598 | 2671 | #endif |
540d72c3 | 2672 | |
2673 | #ifdef GSSAPI | |
2674 | if (compat20 && options.gss_cleanup_creds) | |
2675 | ssh_gssapi_cleanup_creds(); | |
2676 | #endif | |
2677 | ||
2678 | #ifdef USE_PAM | |
2679 | if (options.use_pam) { | |
2680 | sshpam_cleanup(); | |
2681 | sshpam_thread_cleanup(); | |
2682 | } | |
2683 | #endif | |
2684 | ||
2685 | /* remove agent socket */ | |
2686 | auth_sock_cleanup_proc(authctxt->pw); | |
2687 | ||
2688 | /* | |
2689 | * Cleanup ptys/utmp only if privsep is disabled, | |
2690 | * or if running in monitor. | |
2691 | */ | |
2692 | if (!use_privsep || mm_is_monitor()) | |
2693 | session_destroy_all(session_pty_cleanup2); | |
3c0ef626 | 2694 | } |