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3c0ef626 | 1 | /* |
2 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland | |
3 | * All rights reserved | |
4 | * | |
5 | * As far as I am concerned, the code I have written for this software | |
6 | * can be used freely for any purpose. Any derived versions of this | |
7 | * software must be clearly marked as such, and if the derived work is | |
8 | * incompatible with the protocol description in the RFC file, it must be | |
9 | * called by a name other than "ssh" or "Secure Shell". | |
10 | * | |
11 | * SSH2 support by Markus Friedl. | |
12 | * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved. | |
13 | * | |
14 | * Redistribution and use in source and binary forms, with or without | |
15 | * modification, are permitted provided that the following conditions | |
16 | * are met: | |
17 | * 1. Redistributions of source code must retain the above copyright | |
18 | * notice, this list of conditions and the following disclaimer. | |
19 | * 2. Redistributions in binary form must reproduce the above copyright | |
20 | * notice, this list of conditions and the following disclaimer in the | |
21 | * documentation and/or other materials provided with the distribution. | |
22 | * | |
23 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR | |
24 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES | |
25 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. | |
26 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, | |
27 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | |
28 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | |
29 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | |
30 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
31 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | |
32 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
33 | */ | |
34 | ||
35 | #include "includes.h" | |
e54b3d7c | 36 | RCSID("$OpenBSD: session.c,v 1.150 2002/09/16 19:55:33 stevesk 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" | |
45 | #include "mpaux.h" | |
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" | |
2980ea68 | 59 | #include "monitor_wrap.h" |
3c0ef626 | 60 | |
b9a54c29 | 61 | #ifdef GSSAPI |
62 | #include "ssh-gss.h" | |
63 | #endif | |
64 | ||
3c0ef626 | 65 | #ifdef HAVE_CYGWIN |
66 | #include <windows.h> | |
67 | #include <sys/cygwin.h> | |
68 | #define is_winnt (GetVersion() < 0x80000000) | |
69 | #endif | |
70 | ||
3c0ef626 | 71 | /* func */ |
72 | ||
73 | Session *session_new(void); | |
74 | void session_set_fds(Session *, int, int, int); | |
2980ea68 | 75 | void session_pty_cleanup(void *); |
3c0ef626 | 76 | void session_proctitle(Session *); |
77 | int session_setup_x11fwd(Session *); | |
78 | void do_exec_pty(Session *, const char *); | |
79 | void do_exec_no_pty(Session *, const char *); | |
80 | void do_exec(Session *, const char *); | |
81 | void do_login(Session *, const char *); | |
82 | #ifdef LOGIN_NEEDS_UTMPX | |
83 | static void do_pre_login(Session *s); | |
84 | #endif | |
85 | void do_child(Session *, const char *); | |
86 | void do_motd(void); | |
87 | int check_quietlogin(Session *, const char *); | |
88 | ||
89 | static void do_authenticated1(Authctxt *); | |
90 | static void do_authenticated2(Authctxt *); | |
91 | ||
3c0ef626 | 92 | static int session_pty_req(Session *); |
93 | ||
94 | /* import */ | |
95 | extern ServerOptions options; | |
96 | extern char *__progname; | |
97 | extern int log_stderr; | |
98 | extern int debug_flag; | |
99 | extern u_int utmp_len; | |
100 | extern int startup_pipe; | |
101 | extern void destroy_sensitive_data(void); | |
102 | ||
103 | /* original command from peer. */ | |
104 | const char *original_command = NULL; | |
105 | ||
106 | /* data */ | |
107 | #define MAX_SESSIONS 10 | |
108 | Session sessions[MAX_SESSIONS]; | |
109 | ||
110 | #ifdef WITH_AIXAUTHENTICATE | |
111 | char *aixloginmsg; | |
112 | #endif /* WITH_AIXAUTHENTICATE */ | |
113 | ||
114 | #ifdef HAVE_LOGIN_CAP | |
2980ea68 | 115 | login_cap_t *lc; |
3c0ef626 | 116 | #endif |
117 | ||
ff2d7a98 | 118 | /* Name and directory of socket for authentication agent forwarding. */ |
119 | static char *auth_sock_name = NULL; | |
120 | static char *auth_sock_dir = NULL; | |
121 | ||
122 | /* removes the agent forwarding socket */ | |
123 | ||
124 | static void | |
125 | auth_sock_cleanup_proc(void *_pw) | |
126 | { | |
127 | struct passwd *pw = _pw; | |
128 | ||
129 | if (auth_sock_name != NULL) { | |
130 | temporarily_use_uid(pw); | |
131 | unlink(auth_sock_name); | |
132 | rmdir(auth_sock_dir); | |
133 | auth_sock_name = NULL; | |
134 | restore_uid(); | |
135 | } | |
136 | } | |
137 | ||
138 | static int | |
139 | auth_input_request_forwarding(struct passwd * pw) | |
140 | { | |
141 | Channel *nc; | |
142 | int sock; | |
143 | struct sockaddr_un sunaddr; | |
144 | ||
145 | if (auth_sock_name != NULL) { | |
146 | error("authentication forwarding requested twice."); | |
147 | return 0; | |
148 | } | |
149 | ||
150 | /* Temporarily drop privileged uid for mkdir/bind. */ | |
151 | temporarily_use_uid(pw); | |
152 | ||
153 | /* Allocate a buffer for the socket name, and format the name. */ | |
154 | auth_sock_name = xmalloc(MAXPATHLEN); | |
155 | auth_sock_dir = xmalloc(MAXPATHLEN); | |
156 | strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXX", MAXPATHLEN); | |
157 | ||
158 | /* Create private directory for socket */ | |
159 | if (mkdtemp(auth_sock_dir) == NULL) { | |
160 | packet_send_debug("Agent forwarding disabled: " | |
161 | "mkdtemp() failed: %.100s", strerror(errno)); | |
162 | restore_uid(); | |
163 | xfree(auth_sock_name); | |
164 | xfree(auth_sock_dir); | |
165 | auth_sock_name = NULL; | |
166 | auth_sock_dir = NULL; | |
167 | return 0; | |
168 | } | |
169 | snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%ld", | |
170 | auth_sock_dir, (long) getpid()); | |
171 | ||
172 | /* delete agent socket on fatal() */ | |
173 | fatal_add_cleanup(auth_sock_cleanup_proc, pw); | |
174 | ||
175 | /* Create the socket. */ | |
176 | sock = socket(AF_UNIX, SOCK_STREAM, 0); | |
177 | if (sock < 0) | |
178 | packet_disconnect("socket: %.100s", strerror(errno)); | |
179 | ||
180 | /* Bind it to the name. */ | |
181 | memset(&sunaddr, 0, sizeof(sunaddr)); | |
182 | sunaddr.sun_family = AF_UNIX; | |
183 | strlcpy(sunaddr.sun_path, auth_sock_name, sizeof(sunaddr.sun_path)); | |
184 | ||
185 | if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) | |
186 | packet_disconnect("bind: %.100s", strerror(errno)); | |
187 | ||
188 | /* Restore the privileged uid. */ | |
189 | restore_uid(); | |
190 | ||
191 | /* Start listening on the socket. */ | |
192 | if (listen(sock, 5) < 0) | |
193 | packet_disconnect("listen: %.100s", strerror(errno)); | |
194 | ||
195 | /* Allocate a channel for the authentication agent socket. */ | |
196 | nc = channel_new("auth socket", | |
197 | SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1, | |
198 | CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, | |
199 | 0, xstrdup("auth socket"), 1); | |
200 | strlcpy(nc->path, auth_sock_name, sizeof(nc->path)); | |
201 | return 1; | |
202 | } | |
203 | ||
204 | ||
3c0ef626 | 205 | void |
206 | do_authenticated(Authctxt *authctxt) | |
207 | { | |
208 | /* | |
209 | * Cancel the alarm we set to limit the time taken for | |
210 | * authentication. | |
211 | */ | |
212 | alarm(0); | |
213 | if (startup_pipe != -1) { | |
214 | close(startup_pipe); | |
215 | startup_pipe = -1; | |
216 | } | |
3c0ef626 | 217 | |
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 | ||
227 | /* remove agent socket */ | |
ff2d7a98 | 228 | if (auth_sock_name != NULL) |
3c0ef626 | 229 | auth_sock_cleanup_proc(authctxt->pw); |
230 | #ifdef KRB4 | |
231 | if (options.kerberos_ticket_cleanup) | |
232 | krb4_cleanup_proc(authctxt); | |
233 | #endif | |
234 | #ifdef KRB5 | |
235 | if (options.kerberos_ticket_cleanup) | |
236 | krb5_cleanup_proc(authctxt); | |
237 | #endif | |
238 | } | |
239 | ||
240 | /* | |
241 | * Prepares for an interactive session. This is called after the user has | |
242 | * been successfully authenticated. During this message exchange, pseudo | |
243 | * terminals are allocated, X11, TCP/IP, and authentication agent forwardings | |
244 | * are requested, etc. | |
245 | */ | |
246 | static void | |
247 | do_authenticated1(Authctxt *authctxt) | |
248 | { | |
249 | Session *s; | |
250 | char *command; | |
e9a17296 | 251 | int success, type, screen_flag; |
ff2d7a98 | 252 | int enable_compression_after_reply = 0; |
253 | u_int proto_len, data_len, dlen, compression_level = 0; | |
3c0ef626 | 254 | |
255 | s = session_new(); | |
256 | s->authctxt = authctxt; | |
257 | s->pw = authctxt->pw; | |
258 | ||
259 | /* | |
260 | * We stay in this loop until the client requests to execute a shell | |
261 | * or a command. | |
262 | */ | |
263 | for (;;) { | |
264 | success = 0; | |
265 | ||
266 | /* Get a packet from the client. */ | |
e9a17296 | 267 | type = packet_read(); |
3c0ef626 | 268 | |
269 | /* Process the packet. */ | |
270 | switch (type) { | |
271 | case SSH_CMSG_REQUEST_COMPRESSION: | |
3c0ef626 | 272 | compression_level = packet_get_int(); |
e9a17296 | 273 | packet_check_eom(); |
3c0ef626 | 274 | if (compression_level < 1 || compression_level > 9) { |
275 | packet_send_debug("Received illegal compression level %d.", | |
e9a17296 | 276 | compression_level); |
3c0ef626 | 277 | break; |
278 | } | |
ff2d7a98 | 279 | if (!options.compression) { |
280 | debug2("compression disabled"); | |
281 | break; | |
282 | } | |
3c0ef626 | 283 | /* Enable compression after we have responded with SUCCESS. */ |
284 | enable_compression_after_reply = 1; | |
285 | success = 1; | |
286 | break; | |
287 | ||
288 | case SSH_CMSG_REQUEST_PTY: | |
289 | success = session_pty_req(s); | |
290 | break; | |
291 | ||
292 | case SSH_CMSG_X11_REQUEST_FORWARDING: | |
293 | s->auth_proto = packet_get_string(&proto_len); | |
294 | s->auth_data = packet_get_string(&data_len); | |
295 | ||
296 | screen_flag = packet_get_protocol_flags() & | |
297 | SSH_PROTOFLAG_SCREEN_NUMBER; | |
298 | debug2("SSH_PROTOFLAG_SCREEN_NUMBER: %d", screen_flag); | |
299 | ||
300 | if (packet_remaining() == 4) { | |
301 | if (!screen_flag) | |
302 | debug2("Buggy client: " | |
303 | "X11 screen flag missing"); | |
304 | s->screen = packet_get_int(); | |
305 | } else { | |
306 | s->screen = 0; | |
307 | } | |
e9a17296 | 308 | packet_check_eom(); |
3c0ef626 | 309 | success = session_setup_x11fwd(s); |
310 | if (!success) { | |
311 | xfree(s->auth_proto); | |
312 | xfree(s->auth_data); | |
313 | s->auth_proto = NULL; | |
314 | s->auth_data = NULL; | |
315 | } | |
316 | break; | |
317 | ||
318 | case SSH_CMSG_AGENT_REQUEST_FORWARDING: | |
319 | if (no_agent_forwarding_flag || compat13) { | |
320 | debug("Authentication agent forwarding not permitted for this authentication."); | |
321 | break; | |
322 | } | |
323 | debug("Received authentication agent forwarding request."); | |
324 | success = auth_input_request_forwarding(s->pw); | |
325 | break; | |
326 | ||
327 | case SSH_CMSG_PORT_FORWARD_REQUEST: | |
328 | if (no_port_forwarding_flag) { | |
329 | debug("Port forwarding not permitted for this authentication."); | |
330 | break; | |
331 | } | |
332 | if (!options.allow_tcp_forwarding) { | |
333 | debug("Port forwarding not permitted."); | |
334 | break; | |
335 | } | |
336 | debug("Received TCP/IP port forwarding request."); | |
337 | channel_input_port_forward_request(s->pw->pw_uid == 0, options.gateway_ports); | |
338 | success = 1; | |
339 | break; | |
340 | ||
341 | case SSH_CMSG_MAX_PACKET_SIZE: | |
342 | if (packet_set_maxsize(packet_get_int()) > 0) | |
343 | success = 1; | |
344 | break; | |
e9a17296 | 345 | |
3c0ef626 | 346 | #if defined(AFS) || defined(KRB5) |
347 | case SSH_CMSG_HAVE_KERBEROS_TGT: | |
348 | if (!options.kerberos_tgt_passing) { | |
349 | verbose("Kerberos TGT passing disabled."); | |
350 | } else { | |
351 | char *kdata = packet_get_string(&dlen); | |
e9a17296 | 352 | packet_check_eom(); |
353 | ||
3c0ef626 | 354 | /* XXX - 0x41, see creds_to_radix version */ |
355 | if (kdata[0] != 0x41) { | |
356 | #ifdef KRB5 | |
357 | krb5_data tgt; | |
358 | tgt.data = kdata; | |
359 | tgt.length = dlen; | |
e9a17296 | 360 | |
3c0ef626 | 361 | if (auth_krb5_tgt(s->authctxt, &tgt)) |
362 | success = 1; | |
363 | else | |
364 | verbose("Kerberos v5 TGT refused for %.100s", s->authctxt->user); | |
365 | #endif /* KRB5 */ | |
366 | } else { | |
367 | #ifdef AFS | |
368 | if (auth_krb4_tgt(s->authctxt, kdata)) | |
369 | success = 1; | |
370 | else | |
371 | verbose("Kerberos v4 TGT refused for %.100s", s->authctxt->user); | |
372 | #endif /* AFS */ | |
373 | } | |
374 | xfree(kdata); | |
375 | } | |
376 | break; | |
377 | #endif /* AFS || KRB5 */ | |
e9a17296 | 378 | |
3c0ef626 | 379 | #ifdef AFS |
380 | case SSH_CMSG_HAVE_AFS_TOKEN: | |
381 | if (!options.afs_token_passing || !k_hasafs()) { | |
382 | verbose("AFS token passing disabled."); | |
383 | } else { | |
384 | /* Accept AFS token. */ | |
385 | char *token = packet_get_string(&dlen); | |
e9a17296 | 386 | packet_check_eom(); |
387 | ||
3c0ef626 | 388 | if (auth_afs_token(s->authctxt, token)) |
389 | success = 1; | |
390 | else | |
391 | verbose("AFS token refused for %.100s", | |
392 | s->authctxt->user); | |
393 | xfree(token); | |
394 | } | |
395 | break; | |
396 | #endif /* AFS */ | |
397 | ||
398 | case SSH_CMSG_EXEC_SHELL: | |
399 | case SSH_CMSG_EXEC_CMD: | |
400 | if (type == SSH_CMSG_EXEC_CMD) { | |
401 | command = packet_get_string(&dlen); | |
402 | debug("Exec command '%.500s'", command); | |
403 | do_exec(s, command); | |
404 | xfree(command); | |
405 | } else { | |
406 | do_exec(s, NULL); | |
407 | } | |
e9a17296 | 408 | packet_check_eom(); |
3c0ef626 | 409 | session_close(s); |
410 | return; | |
411 | ||
412 | default: | |
413 | /* | |
414 | * Any unknown messages in this phase are ignored, | |
415 | * and a failure message is returned. | |
416 | */ | |
417 | log("Unknown packet type received after authentication: %d", type); | |
418 | } | |
419 | packet_start(success ? SSH_SMSG_SUCCESS : SSH_SMSG_FAILURE); | |
420 | packet_send(); | |
421 | packet_write_wait(); | |
422 | ||
423 | /* Enable compression now that we have replied if appropriate. */ | |
424 | if (enable_compression_after_reply) { | |
425 | enable_compression_after_reply = 0; | |
426 | packet_start_compression(compression_level); | |
427 | } | |
428 | } | |
429 | } | |
430 | ||
431 | /* | |
432 | * This is called to fork and execute a command when we have no tty. This | |
433 | * will call do_child from the child, and server_loop from the parent after | |
434 | * setting up file descriptors and such. | |
435 | */ | |
436 | void | |
437 | do_exec_no_pty(Session *s, const char *command) | |
438 | { | |
ff2d7a98 | 439 | pid_t pid; |
3c0ef626 | 440 | |
441 | #ifdef USE_PIPES | |
442 | int pin[2], pout[2], perr[2]; | |
443 | /* Allocate pipes for communicating with the program. */ | |
444 | if (pipe(pin) < 0 || pipe(pout) < 0 || pipe(perr) < 0) | |
445 | packet_disconnect("Could not create pipes: %.100s", | |
446 | strerror(errno)); | |
447 | #else /* USE_PIPES */ | |
448 | int inout[2], err[2]; | |
449 | /* Uses socket pairs to communicate with the program. */ | |
450 | if (socketpair(AF_UNIX, SOCK_STREAM, 0, inout) < 0 || | |
451 | socketpair(AF_UNIX, SOCK_STREAM, 0, err) < 0) | |
452 | packet_disconnect("Could not create socket pairs: %.100s", | |
453 | strerror(errno)); | |
454 | #endif /* USE_PIPES */ | |
455 | if (s == NULL) | |
456 | fatal("do_exec_no_pty: no session"); | |
457 | ||
458 | session_proctitle(s); | |
459 | ||
b9a54c29 | 460 | #if defined(GSSAPI) |
461 | temporarily_use_uid(s->pw); | |
462 | ssh_gssapi_storecreds(); | |
463 | restore_uid(); | |
464 | #endif | |
465 | ||
3c0ef626 | 466 | #if defined(USE_PAM) |
467 | do_pam_session(s->pw->pw_name, NULL); | |
468 | do_pam_setcred(1); | |
469 | if (is_pam_password_change_required()) | |
470 | packet_disconnect("Password change required but no " | |
471 | "TTY available"); | |
472 | #endif /* USE_PAM */ | |
473 | ||
474 | /* Fork the child. */ | |
475 | if ((pid = fork()) == 0) { | |
e54b3d7c | 476 | fatal_remove_all_cleanups(); |
477 | ||
3c0ef626 | 478 | /* Child. Reinitialize the log since the pid has changed. */ |
479 | log_init(__progname, options.log_level, options.log_facility, log_stderr); | |
480 | ||
481 | /* | |
482 | * Create a new session and process group since the 4.4BSD | |
483 | * setlogin() affects the entire process group. | |
484 | */ | |
485 | if (setsid() < 0) | |
486 | error("setsid failed: %.100s", strerror(errno)); | |
487 | ||
488 | #ifdef USE_PIPES | |
489 | /* | |
490 | * Redirect stdin. We close the parent side of the socket | |
491 | * pair, and make the child side the standard input. | |
492 | */ | |
493 | close(pin[1]); | |
494 | if (dup2(pin[0], 0) < 0) | |
495 | perror("dup2 stdin"); | |
496 | close(pin[0]); | |
497 | ||
498 | /* Redirect stdout. */ | |
499 | close(pout[0]); | |
500 | if (dup2(pout[1], 1) < 0) | |
501 | perror("dup2 stdout"); | |
502 | close(pout[1]); | |
503 | ||
504 | /* Redirect stderr. */ | |
505 | close(perr[0]); | |
506 | if (dup2(perr[1], 2) < 0) | |
507 | perror("dup2 stderr"); | |
508 | close(perr[1]); | |
509 | #else /* USE_PIPES */ | |
510 | /* | |
511 | * Redirect stdin, stdout, and stderr. Stdin and stdout will | |
512 | * use the same socket, as some programs (particularly rdist) | |
513 | * seem to depend on it. | |
514 | */ | |
515 | close(inout[1]); | |
516 | close(err[1]); | |
517 | if (dup2(inout[0], 0) < 0) /* stdin */ | |
518 | perror("dup2 stdin"); | |
519 | if (dup2(inout[0], 1) < 0) /* stdout. Note: same socket as stdin. */ | |
520 | perror("dup2 stdout"); | |
521 | if (dup2(err[0], 2) < 0) /* stderr */ | |
522 | perror("dup2 stderr"); | |
523 | #endif /* USE_PIPES */ | |
524 | ||
e54b3d7c | 525 | #ifdef _UNICOS |
526 | cray_init_job(s->pw); /* set up cray jid and tmpdir */ | |
527 | #endif | |
528 | ||
3c0ef626 | 529 | /* Do processing for the child (exec command etc). */ |
530 | do_child(s, command); | |
531 | /* NOTREACHED */ | |
532 | } | |
e54b3d7c | 533 | #ifdef _UNICOS |
534 | signal(WJSIGNAL, cray_job_termination_handler); | |
535 | #endif /* _UNICOS */ | |
3c0ef626 | 536 | #ifdef HAVE_CYGWIN |
537 | if (is_winnt) | |
538 | cygwin_set_impersonation_token(INVALID_HANDLE_VALUE); | |
539 | #endif | |
540 | if (pid < 0) | |
541 | packet_disconnect("fork failed: %.100s", strerror(errno)); | |
542 | s->pid = pid; | |
543 | /* Set interactive/non-interactive mode. */ | |
544 | packet_set_interactive(s->display != NULL); | |
545 | #ifdef USE_PIPES | |
546 | /* We are the parent. Close the child sides of the pipes. */ | |
547 | close(pin[0]); | |
548 | close(pout[1]); | |
549 | close(perr[1]); | |
550 | ||
551 | if (compat20) { | |
552 | session_set_fds(s, pin[1], pout[0], s->is_subsystem ? -1 : perr[0]); | |
553 | } else { | |
554 | /* Enter the interactive session. */ | |
555 | server_loop(pid, pin[1], pout[0], perr[0]); | |
556 | /* server_loop has closed pin[1], pout[0], and perr[0]. */ | |
557 | } | |
558 | #else /* USE_PIPES */ | |
559 | /* We are the parent. Close the child sides of the socket pairs. */ | |
560 | close(inout[0]); | |
561 | close(err[0]); | |
562 | ||
563 | /* | |
564 | * Enter the interactive session. Note: server_loop must be able to | |
565 | * handle the case that fdin and fdout are the same. | |
566 | */ | |
567 | if (compat20) { | |
568 | session_set_fds(s, inout[1], inout[1], s->is_subsystem ? -1 : err[1]); | |
569 | } else { | |
570 | server_loop(pid, inout[1], inout[1], err[1]); | |
571 | /* server_loop has closed inout[1] and err[1]. */ | |
572 | } | |
573 | #endif /* USE_PIPES */ | |
574 | } | |
575 | ||
576 | /* | |
577 | * This is called to fork and execute a command when we have a tty. This | |
578 | * will call do_child from the child, and server_loop from the parent after | |
579 | * setting up file descriptors, controlling tty, updating wtmp, utmp, | |
580 | * lastlog, and other such operations. | |
581 | */ | |
582 | void | |
583 | do_exec_pty(Session *s, const char *command) | |
584 | { | |
585 | int fdout, ptyfd, ttyfd, ptymaster; | |
586 | pid_t pid; | |
587 | ||
588 | if (s == NULL) | |
589 | fatal("do_exec_pty: no session"); | |
590 | ptyfd = s->ptyfd; | |
591 | ttyfd = s->ttyfd; | |
592 | ||
b9a54c29 | 593 | #if defined(GSSAPI) |
594 | temporarily_use_uid(s->pw); | |
595 | ssh_gssapi_storecreds(); | |
596 | restore_uid(); | |
597 | #endif | |
598 | ||
3c0ef626 | 599 | #if defined(USE_PAM) |
600 | do_pam_session(s->pw->pw_name, s->tty); | |
601 | do_pam_setcred(1); | |
602 | #endif | |
603 | ||
604 | /* Fork the child. */ | |
605 | if ((pid = fork()) == 0) { | |
e54b3d7c | 606 | fatal_remove_all_cleanups(); |
3c0ef626 | 607 | |
608 | /* Child. Reinitialize the log because the pid has changed. */ | |
609 | log_init(__progname, options.log_level, options.log_facility, log_stderr); | |
610 | /* Close the master side of the pseudo tty. */ | |
611 | close(ptyfd); | |
612 | ||
613 | /* Make the pseudo tty our controlling tty. */ | |
614 | pty_make_controlling_tty(&ttyfd, s->tty); | |
615 | ||
616 | /* Redirect stdin/stdout/stderr from the pseudo tty. */ | |
617 | if (dup2(ttyfd, 0) < 0) | |
618 | error("dup2 stdin: %s", strerror(errno)); | |
619 | if (dup2(ttyfd, 1) < 0) | |
620 | error("dup2 stdout: %s", strerror(errno)); | |
621 | if (dup2(ttyfd, 2) < 0) | |
622 | error("dup2 stderr: %s", strerror(errno)); | |
623 | ||
624 | /* Close the extra descriptor for the pseudo tty. */ | |
625 | close(ttyfd); | |
626 | ||
627 | /* record login, etc. similar to login(1) */ | |
628 | #ifndef HAVE_OSF_SIA | |
e54b3d7c | 629 | if (!(options.use_login && command == NULL)) { |
630 | #ifdef _UNICOS | |
631 | cray_init_job(s->pw); /* set up cray jid and tmpdir */ | |
632 | #endif /* _UNICOS */ | |
3c0ef626 | 633 | do_login(s, command); |
e54b3d7c | 634 | } |
3c0ef626 | 635 | # ifdef LOGIN_NEEDS_UTMPX |
636 | else | |
637 | do_pre_login(s); | |
638 | # endif | |
639 | #endif | |
640 | ||
641 | /* Do common processing for the child, such as execing the command. */ | |
642 | do_child(s, command); | |
643 | /* NOTREACHED */ | |
644 | } | |
e54b3d7c | 645 | #ifdef _UNICOS |
646 | signal(WJSIGNAL, cray_job_termination_handler); | |
647 | #endif /* _UNICOS */ | |
3c0ef626 | 648 | #ifdef HAVE_CYGWIN |
649 | if (is_winnt) | |
650 | cygwin_set_impersonation_token(INVALID_HANDLE_VALUE); | |
651 | #endif | |
652 | if (pid < 0) | |
653 | packet_disconnect("fork failed: %.100s", strerror(errno)); | |
654 | s->pid = pid; | |
655 | ||
656 | /* Parent. Close the slave side of the pseudo tty. */ | |
657 | close(ttyfd); | |
658 | ||
659 | /* | |
660 | * Create another descriptor of the pty master side for use as the | |
661 | * standard input. We could use the original descriptor, but this | |
662 | * simplifies code in server_loop. The descriptor is bidirectional. | |
663 | */ | |
664 | fdout = dup(ptyfd); | |
665 | if (fdout < 0) | |
666 | packet_disconnect("dup #1 failed: %.100s", strerror(errno)); | |
667 | ||
668 | /* we keep a reference to the pty master */ | |
669 | ptymaster = dup(ptyfd); | |
670 | if (ptymaster < 0) | |
671 | packet_disconnect("dup #2 failed: %.100s", strerror(errno)); | |
672 | s->ptymaster = ptymaster; | |
673 | ||
674 | /* Enter interactive session. */ | |
675 | packet_set_interactive(1); | |
676 | if (compat20) { | |
677 | session_set_fds(s, ptyfd, fdout, -1); | |
678 | } else { | |
679 | server_loop(pid, ptyfd, fdout, -1); | |
680 | /* server_loop _has_ closed ptyfd and fdout. */ | |
681 | } | |
682 | } | |
683 | ||
684 | #ifdef LOGIN_NEEDS_UTMPX | |
685 | static void | |
686 | do_pre_login(Session *s) | |
687 | { | |
688 | socklen_t fromlen; | |
689 | struct sockaddr_storage from; | |
690 | pid_t pid = getpid(); | |
691 | ||
692 | /* | |
693 | * Get IP address of client. If the connection is not a socket, let | |
694 | * the address be 0.0.0.0. | |
695 | */ | |
696 | memset(&from, 0, sizeof(from)); | |
e54b3d7c | 697 | fromlen = sizeof(from); |
3c0ef626 | 698 | if (packet_connection_is_on_socket()) { |
3c0ef626 | 699 | if (getpeername(packet_get_connection_in(), |
e9a17296 | 700 | (struct sockaddr *) & from, &fromlen) < 0) { |
3c0ef626 | 701 | debug("getpeername: %.100s", strerror(errno)); |
702 | fatal_cleanup(); | |
703 | } | |
704 | } | |
705 | ||
706 | record_utmp_only(pid, s->tty, s->pw->pw_name, | |
e9a17296 | 707 | get_remote_name_or_ip(utmp_len, options.verify_reverse_mapping), |
3c0ef626 | 708 | (struct sockaddr *)&from); |
709 | } | |
710 | #endif | |
711 | ||
712 | /* | |
713 | * This is called to fork and execute a command. If another command is | |
714 | * to be forced, execute that instead. | |
715 | */ | |
716 | void | |
717 | do_exec(Session *s, const char *command) | |
718 | { | |
719 | if (forced_command) { | |
720 | original_command = command; | |
721 | command = forced_command; | |
722 | debug("Forced command '%.900s'", command); | |
723 | } | |
724 | ||
725 | if (s->ttyfd != -1) | |
726 | do_exec_pty(s, command); | |
727 | else | |
728 | do_exec_no_pty(s, command); | |
729 | ||
730 | original_command = NULL; | |
731 | } | |
732 | ||
e9a17296 | 733 | |
3c0ef626 | 734 | /* administrative, login(1)-like work */ |
735 | void | |
736 | do_login(Session *s, const char *command) | |
737 | { | |
738 | char *time_string; | |
3c0ef626 | 739 | socklen_t fromlen; |
740 | struct sockaddr_storage from; | |
3c0ef626 | 741 | struct passwd * pw = s->pw; |
742 | pid_t pid = getpid(); | |
743 | ||
744 | /* | |
745 | * Get IP address of client. If the connection is not a socket, let | |
746 | * the address be 0.0.0.0. | |
747 | */ | |
748 | memset(&from, 0, sizeof(from)); | |
749 | if (packet_connection_is_on_socket()) { | |
750 | fromlen = sizeof(from); | |
751 | if (getpeername(packet_get_connection_in(), | |
e9a17296 | 752 | (struct sockaddr *) & from, &fromlen) < 0) { |
3c0ef626 | 753 | debug("getpeername: %.100s", strerror(errno)); |
754 | fatal_cleanup(); | |
755 | } | |
756 | } | |
757 | ||
3c0ef626 | 758 | /* Record that there was a login on that tty from the remote host. */ |
2980ea68 | 759 | if (!use_privsep) |
760 | record_login(pid, s->tty, pw->pw_name, pw->pw_uid, | |
761 | get_remote_name_or_ip(utmp_len, | |
762 | options.verify_reverse_mapping), | |
e54b3d7c | 763 | (struct sockaddr *)&from, fromlen); |
3c0ef626 | 764 | |
765 | #ifdef USE_PAM | |
766 | /* | |
767 | * If password change is needed, do it now. | |
768 | * This needs to occur before the ~/.hushlogin check. | |
769 | */ | |
770 | if (is_pam_password_change_required()) { | |
771 | print_pam_messages(); | |
772 | do_pam_chauthtok(); | |
773 | } | |
774 | #endif | |
775 | ||
776 | if (check_quietlogin(s, command)) | |
777 | return; | |
778 | ||
779 | #ifdef USE_PAM | |
780 | if (!is_pam_password_change_required()) | |
781 | print_pam_messages(); | |
782 | #endif /* USE_PAM */ | |
783 | #ifdef WITH_AIXAUTHENTICATE | |
784 | if (aixloginmsg && *aixloginmsg) | |
785 | printf("%s\n", aixloginmsg); | |
786 | #endif /* WITH_AIXAUTHENTICATE */ | |
787 | ||
e54b3d7c | 788 | #ifndef NO_SSH_LASTLOG |
2980ea68 | 789 | if (options.print_lastlog && s->last_login_time != 0) { |
790 | time_string = ctime(&s->last_login_time); | |
3c0ef626 | 791 | if (strchr(time_string, '\n')) |
792 | *strchr(time_string, '\n') = 0; | |
2980ea68 | 793 | if (strcmp(s->hostname, "") == 0) |
3c0ef626 | 794 | printf("Last login: %s\r\n", time_string); |
795 | else | |
2980ea68 | 796 | printf("Last login: %s from %s\r\n", time_string, |
797 | s->hostname); | |
3c0ef626 | 798 | } |
e54b3d7c | 799 | #endif /* NO_SSH_LASTLOG */ |
3c0ef626 | 800 | |
801 | do_motd(); | |
802 | } | |
803 | ||
804 | /* | |
805 | * Display the message of the day. | |
806 | */ | |
807 | void | |
808 | do_motd(void) | |
809 | { | |
810 | FILE *f; | |
811 | char buf[256]; | |
812 | ||
813 | if (options.print_motd) { | |
814 | #ifdef HAVE_LOGIN_CAP | |
815 | f = fopen(login_getcapstr(lc, "welcome", "/etc/motd", | |
816 | "/etc/motd"), "r"); | |
817 | #else | |
818 | f = fopen("/etc/motd", "r"); | |
819 | #endif | |
820 | if (f) { | |
821 | while (fgets(buf, sizeof(buf), f)) | |
822 | fputs(buf, stdout); | |
823 | fclose(f); | |
824 | } | |
825 | } | |
826 | } | |
827 | ||
828 | ||
829 | /* | |
830 | * Check for quiet login, either .hushlogin or command given. | |
831 | */ | |
832 | int | |
833 | check_quietlogin(Session *s, const char *command) | |
834 | { | |
835 | char buf[256]; | |
836 | struct passwd *pw = s->pw; | |
837 | struct stat st; | |
838 | ||
839 | /* Return 1 if .hushlogin exists or a command given. */ | |
840 | if (command != NULL) | |
841 | return 1; | |
842 | snprintf(buf, sizeof(buf), "%.200s/.hushlogin", pw->pw_dir); | |
843 | #ifdef HAVE_LOGIN_CAP | |
844 | if (login_getcapbool(lc, "hushlogin", 0) || stat(buf, &st) >= 0) | |
845 | return 1; | |
846 | #else | |
847 | if (stat(buf, &st) >= 0) | |
848 | return 1; | |
849 | #endif | |
850 | return 0; | |
851 | } | |
852 | ||
853 | /* | |
854 | * Sets the value of the given variable in the environment. If the variable | |
855 | * already exists, its value is overriden. | |
856 | */ | |
b9a54c29 | 857 | void |
3c0ef626 | 858 | child_set_env(char ***envp, u_int *envsizep, const char *name, |
e9a17296 | 859 | const char *value) |
3c0ef626 | 860 | { |
861 | u_int i, namelen; | |
862 | char **env; | |
863 | ||
864 | /* | |
865 | * Find the slot where the value should be stored. If the variable | |
866 | * already exists, we reuse the slot; otherwise we append a new slot | |
867 | * at the end of the array, expanding if necessary. | |
868 | */ | |
869 | env = *envp; | |
870 | namelen = strlen(name); | |
871 | for (i = 0; env[i]; i++) | |
872 | if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=') | |
873 | break; | |
874 | if (env[i]) { | |
875 | /* Reuse the slot. */ | |
876 | xfree(env[i]); | |
877 | } else { | |
878 | /* New variable. Expand if necessary. */ | |
879 | if (i >= (*envsizep) - 1) { | |
ff2d7a98 | 880 | if (*envsizep >= 1000) |
881 | fatal("child_set_env: too many env vars," | |
882 | " skipping: %.100s", name); | |
3c0ef626 | 883 | (*envsizep) += 50; |
884 | env = (*envp) = xrealloc(env, (*envsizep) * sizeof(char *)); | |
885 | } | |
886 | /* Need to set the NULL pointer at end of array beyond the new slot. */ | |
887 | env[i + 1] = NULL; | |
888 | } | |
889 | ||
890 | /* Allocate space and format the variable in the appropriate slot. */ | |
891 | env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1); | |
892 | snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value); | |
893 | } | |
894 | ||
895 | /* | |
896 | * Reads environment variables from the given file and adds/overrides them | |
897 | * into the environment. If the file does not exist, this does nothing. | |
898 | * Otherwise, it must consist of empty lines, comments (line starts with '#') | |
899 | * and assignments of the form name=value. No other forms are allowed. | |
900 | */ | |
901 | static void | |
902 | read_environment_file(char ***env, u_int *envsize, | |
e9a17296 | 903 | const char *filename) |
3c0ef626 | 904 | { |
905 | FILE *f; | |
906 | char buf[4096]; | |
907 | char *cp, *value; | |
ff2d7a98 | 908 | u_int lineno = 0; |
3c0ef626 | 909 | |
910 | f = fopen(filename, "r"); | |
911 | if (!f) | |
912 | return; | |
913 | ||
914 | while (fgets(buf, sizeof(buf), f)) { | |
ff2d7a98 | 915 | if (++lineno > 1000) |
916 | fatal("Too many lines in environment file %s", filename); | |
3c0ef626 | 917 | for (cp = buf; *cp == ' ' || *cp == '\t'; cp++) |
918 | ; | |
919 | if (!*cp || *cp == '#' || *cp == '\n') | |
920 | continue; | |
921 | if (strchr(cp, '\n')) | |
922 | *strchr(cp, '\n') = '\0'; | |
923 | value = strchr(cp, '='); | |
924 | if (value == NULL) { | |
ff2d7a98 | 925 | fprintf(stderr, "Bad line %u in %.100s\n", lineno, |
926 | filename); | |
3c0ef626 | 927 | continue; |
928 | } | |
929 | /* | |
930 | * Replace the equals sign by nul, and advance value to | |
931 | * the value string. | |
932 | */ | |
933 | *value = '\0'; | |
934 | value++; | |
935 | child_set_env(env, envsize, cp, value); | |
936 | } | |
937 | fclose(f); | |
938 | } | |
939 | ||
e9a17296 | 940 | void copy_environment(char **source, char ***env, u_int *envsize) |
3c0ef626 | 941 | { |
e9a17296 | 942 | char *var_name, *var_val; |
3c0ef626 | 943 | int i; |
944 | ||
e9a17296 | 945 | if (source == NULL) |
3c0ef626 | 946 | return; |
947 | ||
e9a17296 | 948 | for(i = 0; source[i] != NULL; i++) { |
949 | var_name = xstrdup(source[i]); | |
950 | if ((var_val = strstr(var_name, "=")) == NULL) { | |
951 | xfree(var_name); | |
3c0ef626 | 952 | continue; |
3c0ef626 | 953 | } |
e9a17296 | 954 | *var_val++ = '\0'; |
3c0ef626 | 955 | |
e9a17296 | 956 | debug3("Copy environment: %s=%s", var_name, var_val); |
957 | child_set_env(env, envsize, var_name, var_val); | |
958 | ||
959 | xfree(var_name); | |
3c0ef626 | 960 | } |
961 | } | |
3c0ef626 | 962 | |
e9a17296 | 963 | static char ** |
964 | do_setup_env(Session *s, const char *shell) | |
3c0ef626 | 965 | { |
3c0ef626 | 966 | char buf[256]; |
e9a17296 | 967 | u_int i, envsize; |
3c0ef626 | 968 | char **env; |
e9a17296 | 969 | struct passwd *pw = s->pw; |
3c0ef626 | 970 | |
971 | /* Initialize the environment. */ | |
972 | envsize = 100; | |
973 | env = xmalloc(envsize * sizeof(char *)); | |
974 | env[0] = NULL; | |
975 | ||
976 | #ifdef HAVE_CYGWIN | |
977 | /* | |
978 | * The Windows environment contains some setting which are | |
979 | * important for a running system. They must not be dropped. | |
980 | */ | |
e9a17296 | 981 | copy_environment(environ, &env, &envsize); |
3c0ef626 | 982 | #endif |
983 | ||
b9a54c29 | 984 | #ifdef GSSAPI |
985 | /* Allow any GSSAPI methods that we've used to alter | |
986 | * the childs environment as they see fit | |
987 | */ | |
988 | ssh_gssapi_do_child(&env,&envsize); | |
989 | #endif | |
990 | ||
3c0ef626 | 991 | if (!options.use_login) { |
992 | /* Set basic environment. */ | |
993 | child_set_env(&env, &envsize, "USER", pw->pw_name); | |
994 | child_set_env(&env, &envsize, "LOGNAME", pw->pw_name); | |
995 | child_set_env(&env, &envsize, "HOME", pw->pw_dir); | |
996 | #ifdef HAVE_LOGIN_CAP | |
e54b3d7c | 997 | if (setusercontext(lc, pw, pw->pw_uid, LOGIN_SETPATH) < 0) |
998 | child_set_env(&env, &envsize, "PATH", _PATH_STDPATH); | |
999 | else | |
1000 | child_set_env(&env, &envsize, "PATH", getenv("PATH")); | |
3c0ef626 | 1001 | #else /* HAVE_LOGIN_CAP */ |
1002 | # ifndef HAVE_CYGWIN | |
1003 | /* | |
1004 | * There's no standard path on Windows. The path contains | |
1005 | * important components pointing to the system directories, | |
1006 | * needed for loading shared libraries. So the path better | |
1007 | * remains intact here. | |
1008 | */ | |
2980ea68 | 1009 | # ifdef SUPERUSER_PATH |
1010 | child_set_env(&env, &envsize, "PATH", | |
1011 | s->pw->pw_uid == 0 ? SUPERUSER_PATH : | |
1012 | _PATH_STDPATH_WITH_SCP); | |
1013 | # else | |
4a23e2c2 | 1014 | child_set_env(&env, &envsize, "PATH", _PATH_STDPATH_WITH_SCP); |
2980ea68 | 1015 | # endif /* SUPERUSER_PATH */ |
3c0ef626 | 1016 | # endif /* HAVE_CYGWIN */ |
1017 | #endif /* HAVE_LOGIN_CAP */ | |
1018 | ||
1019 | snprintf(buf, sizeof buf, "%.200s/%.50s", | |
1020 | _PATH_MAILDIR, pw->pw_name); | |
1021 | child_set_env(&env, &envsize, "MAIL", buf); | |
1022 | ||
1023 | /* Normal systems set SHELL by default. */ | |
1024 | child_set_env(&env, &envsize, "SHELL", shell); | |
1025 | } | |
1026 | if (getenv("TZ")) | |
1027 | child_set_env(&env, &envsize, "TZ", getenv("TZ")); | |
1028 | ||
93f82cab | 1029 | #ifdef GSI |
1030 | if (getenv("GLOBUS_LOCATION")) | |
1031 | child_set_env(&env, &envsize, "GLOBUS_LOCATION", | |
1032 | getenv("GLOBUS_LOCATION")); | |
1033 | #endif | |
1034 | ||
3c0ef626 | 1035 | /* Set custom environment options from RSA authentication. */ |
1036 | if (!options.use_login) { | |
1037 | while (custom_environment) { | |
1038 | struct envstring *ce = custom_environment; | |
e54b3d7c | 1039 | char *str = ce->s; |
e9a17296 | 1040 | |
e54b3d7c | 1041 | for (i = 0; str[i] != '=' && str[i]; i++) |
3c0ef626 | 1042 | ; |
e54b3d7c | 1043 | if (str[i] == '=') { |
1044 | str[i] = 0; | |
1045 | child_set_env(&env, &envsize, str, str + i + 1); | |
3c0ef626 | 1046 | } |
1047 | custom_environment = ce->next; | |
1048 | xfree(ce->s); | |
1049 | xfree(ce); | |
1050 | } | |
1051 | } | |
1052 | ||
e54b3d7c | 1053 | /* SSH_CLIENT deprecated */ |
3c0ef626 | 1054 | snprintf(buf, sizeof buf, "%.50s %d %d", |
e9a17296 | 1055 | get_remote_ipaddr(), get_remote_port(), get_local_port()); |
3c0ef626 | 1056 | child_set_env(&env, &envsize, "SSH_CLIENT", buf); |
1057 | ||
e54b3d7c | 1058 | snprintf(buf, sizeof buf, "%.50s %d %.50s %d", |
1059 | get_remote_ipaddr(), get_remote_port(), | |
1060 | get_local_ipaddr(packet_get_connection_in()), get_local_port()); | |
1061 | child_set_env(&env, &envsize, "SSH_CONNECTION", buf); | |
1062 | ||
3c0ef626 | 1063 | if (s->ttyfd != -1) |
1064 | child_set_env(&env, &envsize, "SSH_TTY", s->tty); | |
1065 | if (s->term) | |
1066 | child_set_env(&env, &envsize, "TERM", s->term); | |
1067 | if (s->display) | |
1068 | child_set_env(&env, &envsize, "DISPLAY", s->display); | |
1069 | if (original_command) | |
1070 | child_set_env(&env, &envsize, "SSH_ORIGINAL_COMMAND", | |
1071 | original_command); | |
1072 | ||
e54b3d7c | 1073 | #ifdef _UNICOS |
1074 | if (cray_tmpdir[0] != '\0') | |
1075 | child_set_env(&env, &envsize, "TMPDIR", cray_tmpdir); | |
1076 | #endif /* _UNICOS */ | |
1077 | ||
3c0ef626 | 1078 | #ifdef _AIX |
e9a17296 | 1079 | { |
1080 | char *cp; | |
1081 | ||
1082 | if ((cp = getenv("AUTHSTATE")) != NULL) | |
1083 | child_set_env(&env, &envsize, "AUTHSTATE", cp); | |
1084 | if ((cp = getenv("KRB5CCNAME")) != NULL) | |
1085 | child_set_env(&env, &envsize, "KRB5CCNAME", cp); | |
1086 | read_environment_file(&env, &envsize, "/etc/environment"); | |
1087 | } | |
3c0ef626 | 1088 | #endif |
1089 | #ifdef KRB4 | |
1090 | if (s->authctxt->krb4_ticket_file) | |
1091 | child_set_env(&env, &envsize, "KRBTKFILE", | |
1092 | s->authctxt->krb4_ticket_file); | |
1093 | #endif | |
1094 | #ifdef KRB5 | |
1095 | if (s->authctxt->krb5_ticket_file) | |
1096 | child_set_env(&env, &envsize, "KRB5CCNAME", | |
1097 | s->authctxt->krb5_ticket_file); | |
1098 | #endif | |
1099 | #ifdef USE_PAM | |
e54b3d7c | 1100 | /* |
1101 | * Pull in any environment variables that may have | |
1102 | * been set by PAM. | |
1103 | */ | |
1104 | { | |
1105 | char **p; | |
1106 | ||
1107 | p = fetch_pam_environment(); | |
1108 | copy_environment(p, &env, &envsize); | |
1109 | free_pam_environment(p); | |
1110 | } | |
3c0ef626 | 1111 | #endif /* USE_PAM */ |
1112 | ||
ff2d7a98 | 1113 | if (auth_sock_name != NULL) |
3c0ef626 | 1114 | child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME, |
ff2d7a98 | 1115 | auth_sock_name); |
3c0ef626 | 1116 | |
1117 | /* read $HOME/.ssh/environment. */ | |
e54b3d7c | 1118 | if (options.permit_user_env && !options.use_login) { |
3c0ef626 | 1119 | snprintf(buf, sizeof buf, "%.200s/.ssh/environment", |
e54b3d7c | 1120 | strcmp(pw->pw_dir, "/") ? pw->pw_dir : ""); |
3c0ef626 | 1121 | read_environment_file(&env, &envsize, buf); |
1122 | } | |
1123 | if (debug_flag) { | |
1124 | /* dump the environment */ | |
1125 | fprintf(stderr, "Environment:\n"); | |
1126 | for (i = 0; env[i]; i++) | |
1127 | fprintf(stderr, " %.200s\n", env[i]); | |
1128 | } | |
e9a17296 | 1129 | return env; |
1130 | } | |
1131 | ||
1132 | /* | |
1133 | * Run $HOME/.ssh/rc, /etc/ssh/sshrc, or xauth (whichever is found | |
1134 | * first in this order). | |
1135 | */ | |
1136 | static void | |
1137 | do_rc_files(Session *s, const char *shell) | |
1138 | { | |
1139 | FILE *f = NULL; | |
1140 | char cmd[1024]; | |
1141 | int do_xauth; | |
1142 | struct stat st; | |
1143 | ||
1144 | do_xauth = | |
1145 | s->display != NULL && s->auth_proto != NULL && s->auth_data != NULL; | |
1146 | ||
1147 | /* ignore _PATH_SSH_USER_RC for subsystems */ | |
1148 | if (!s->is_subsystem && (stat(_PATH_SSH_USER_RC, &st) >= 0)) { | |
1149 | snprintf(cmd, sizeof cmd, "%s -c '%s %s'", | |
1150 | shell, _PATH_BSHELL, _PATH_SSH_USER_RC); | |
1151 | if (debug_flag) | |
1152 | fprintf(stderr, "Running %s\n", cmd); | |
1153 | f = popen(cmd, "w"); | |
1154 | if (f) { | |
1155 | if (do_xauth) | |
1156 | fprintf(f, "%s %s\n", s->auth_proto, | |
1157 | s->auth_data); | |
1158 | pclose(f); | |
1159 | } else | |
1160 | fprintf(stderr, "Could not run %s\n", | |
1161 | _PATH_SSH_USER_RC); | |
1162 | } else if (stat(_PATH_SSH_SYSTEM_RC, &st) >= 0) { | |
ae43c103 | 1163 | snprintf(cmd, sizeof cmd, "%s %s", _PATH_BSHELL, |
1164 | _PATH_SSH_SYSTEM_RC); | |
e9a17296 | 1165 | if (debug_flag) |
ae43c103 | 1166 | fprintf(stderr, "Running %s\n", cmd); |
1167 | f = popen(cmd, "w"); | |
e9a17296 | 1168 | if (f) { |
1169 | if (do_xauth) | |
1170 | fprintf(f, "%s %s\n", s->auth_proto, | |
1171 | s->auth_data); | |
1172 | pclose(f); | |
1173 | } else | |
1174 | fprintf(stderr, "Could not run %s\n", | |
1175 | _PATH_SSH_SYSTEM_RC); | |
1176 | } else if (do_xauth && options.xauth_location != NULL) { | |
1177 | /* Add authority data to .Xauthority if appropriate. */ | |
1178 | if (debug_flag) { | |
1179 | fprintf(stderr, | |
ff2d7a98 | 1180 | "Running %.500s add " |
e9a17296 | 1181 | "%.100s %.100s %.100s\n", |
1182 | options.xauth_location, s->auth_display, | |
1183 | s->auth_proto, s->auth_data); | |
1184 | } | |
1185 | snprintf(cmd, sizeof cmd, "%s -q -", | |
1186 | options.xauth_location); | |
1187 | f = popen(cmd, "w"); | |
1188 | if (f) { | |
1189 | fprintf(f, "add %s %s %s\n", | |
1190 | s->auth_display, s->auth_proto, | |
1191 | s->auth_data); | |
1192 | pclose(f); | |
1193 | } else { | |
1194 | fprintf(stderr, "Could not run %s\n", | |
1195 | cmd); | |
1196 | } | |
1197 | } | |
1198 | } | |
1199 | ||
1200 | static void | |
1201 | do_nologin(struct passwd *pw) | |
1202 | { | |
1203 | FILE *f = NULL; | |
1204 | char buf[1024]; | |
1205 | ||
1206 | #ifdef HAVE_LOGIN_CAP | |
1207 | if (!login_getcapbool(lc, "ignorenologin", 0) && pw->pw_uid) | |
1208 | f = fopen(login_getcapstr(lc, "nologin", _PATH_NOLOGIN, | |
1209 | _PATH_NOLOGIN), "r"); | |
1210 | #else | |
1211 | if (pw->pw_uid) | |
1212 | f = fopen(_PATH_NOLOGIN, "r"); | |
1213 | #endif | |
1214 | if (f) { | |
1215 | /* /etc/nologin exists. Print its contents and exit. */ | |
e54b3d7c | 1216 | log("User %.100s not allowed because %s exists", |
1217 | pw->pw_name, _PATH_NOLOGIN); | |
e9a17296 | 1218 | while (fgets(buf, sizeof(buf), f)) |
1219 | fputs(buf, stderr); | |
1220 | fclose(f); | |
1221 | exit(254); | |
1222 | } | |
1223 | } | |
1224 | ||
1225 | /* Set login name, uid, gid, and groups. */ | |
2980ea68 | 1226 | void |
e9a17296 | 1227 | do_setusercontext(struct passwd *pw) |
1228 | { | |
1229 | #ifdef HAVE_CYGWIN | |
1230 | if (is_winnt) { | |
1231 | #else /* HAVE_CYGWIN */ | |
1232 | if (getuid() == 0 || geteuid() == 0) { | |
1233 | #endif /* HAVE_CYGWIN */ | |
ff2d7a98 | 1234 | #ifdef HAVE_SETPCRED |
1235 | setpcred(pw->pw_name); | |
1236 | #endif /* HAVE_SETPCRED */ | |
e9a17296 | 1237 | #ifdef HAVE_LOGIN_CAP |
e54b3d7c | 1238 | # ifdef __bsdi__ |
ff2d7a98 | 1239 | setpgid(0, 0); |
e54b3d7c | 1240 | # endif |
e9a17296 | 1241 | if (setusercontext(lc, pw, pw->pw_uid, |
1242 | (LOGIN_SETALL & ~LOGIN_SETPATH)) < 0) { | |
1243 | perror("unable to set user context"); | |
1244 | exit(1); | |
1245 | } | |
1246 | #else | |
1247 | # if defined(HAVE_GETLUID) && defined(HAVE_SETLUID) | |
1248 | /* Sets login uid for accounting */ | |
1249 | if (getluid() == -1 && setluid(pw->pw_uid) == -1) | |
1250 | error("setluid: %s", strerror(errno)); | |
1251 | # endif /* defined(HAVE_GETLUID) && defined(HAVE_SETLUID) */ | |
1252 | ||
1253 | if (setlogin(pw->pw_name) < 0) | |
1254 | error("setlogin failed: %s", strerror(errno)); | |
1255 | if (setgid(pw->pw_gid) < 0) { | |
1256 | perror("setgid"); | |
1257 | exit(1); | |
1258 | } | |
1259 | /* Initialize the group list. */ | |
1260 | if (initgroups(pw->pw_name, pw->pw_gid) < 0) { | |
1261 | perror("initgroups"); | |
1262 | exit(1); | |
1263 | } | |
1264 | endgrent(); | |
1265 | # ifdef USE_PAM | |
1266 | /* | |
1267 | * PAM credentials may take the form of supplementary groups. | |
1268 | * These will have been wiped by the above initgroups() call. | |
1269 | * Reestablish them here. | |
1270 | */ | |
1271 | do_pam_setcred(0); | |
1272 | # endif /* USE_PAM */ | |
1273 | # if defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) | |
1274 | irix_setusercontext(pw); | |
1275 | # endif /* defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) */ | |
ff2d7a98 | 1276 | # ifdef _AIX |
e54b3d7c | 1277 | aix_usrinfo(pw); |
ff2d7a98 | 1278 | # endif /* _AIX */ |
e9a17296 | 1279 | /* Permanently switch to the desired uid. */ |
1280 | permanently_set_uid(pw); | |
1281 | #endif | |
1282 | } | |
1283 | if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid) | |
1284 | fatal("Failed to set uids to %u.", (u_int) pw->pw_uid); | |
1285 | } | |
1286 | ||
2980ea68 | 1287 | static void |
1288 | launch_login(struct passwd *pw, const char *hostname) | |
1289 | { | |
1290 | /* Launch login(1). */ | |
1291 | ||
ff2d7a98 | 1292 | execl(LOGIN_PROGRAM, "login", "-h", hostname, |
2980ea68 | 1293 | #ifdef xxxLOGIN_NEEDS_TERM |
ff2d7a98 | 1294 | (s->term ? s->term : "unknown"), |
2980ea68 | 1295 | #endif /* LOGIN_NEEDS_TERM */ |
1296 | #ifdef LOGIN_NO_ENDOPT | |
1297 | "-p", "-f", pw->pw_name, (char *)NULL); | |
1298 | #else | |
1299 | "-p", "-f", "--", pw->pw_name, (char *)NULL); | |
1300 | #endif | |
1301 | ||
1302 | /* Login couldn't be executed, die. */ | |
1303 | ||
1304 | perror("login"); | |
1305 | exit(1); | |
1306 | } | |
1307 | ||
e9a17296 | 1308 | /* |
1309 | * Performs common processing for the child, such as setting up the | |
1310 | * environment, closing extra file descriptors, setting the user and group | |
1311 | * ids, and executing the command or shell. | |
1312 | */ | |
1313 | void | |
1314 | do_child(Session *s, const char *command) | |
1315 | { | |
1316 | extern char **environ; | |
1317 | char **env; | |
1318 | char *argv[10]; | |
1319 | const char *shell, *shell0, *hostname = NULL; | |
1320 | struct passwd *pw = s->pw; | |
1321 | u_int i; | |
1322 | ||
1323 | /* remove hostkey from the child's memory */ | |
1324 | destroy_sensitive_data(); | |
1325 | ||
1326 | /* login(1) is only called if we execute the login shell */ | |
1327 | if (options.use_login && command != NULL) | |
1328 | options.use_login = 0; | |
1329 | ||
e54b3d7c | 1330 | #ifdef _UNICOS |
1331 | cray_setup(pw->pw_uid, pw->pw_name, command); | |
1332 | #endif /* _UNICOS */ | |
1333 | ||
e9a17296 | 1334 | /* |
1335 | * Login(1) does this as well, and it needs uid 0 for the "-h" | |
1336 | * switch, so we let login(1) to this for us. | |
1337 | */ | |
1338 | if (!options.use_login) { | |
1339 | #ifdef HAVE_OSF_SIA | |
1340 | session_setup_sia(pw->pw_name, s->ttyfd == -1 ? NULL : s->tty); | |
1341 | if (!check_quietlogin(s, command)) | |
1342 | do_motd(); | |
1343 | #else /* HAVE_OSF_SIA */ | |
1344 | do_nologin(pw); | |
e9a17296 | 1345 | do_setusercontext(pw); |
1346 | #endif /* HAVE_OSF_SIA */ | |
1347 | } | |
1348 | ||
1349 | /* | |
1350 | * Get the shell from the password data. An empty shell field is | |
1351 | * legal, and means /bin/sh. | |
1352 | */ | |
1353 | shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell; | |
1354 | #ifdef HAVE_LOGIN_CAP | |
1355 | shell = login_getcapstr(lc, "shell", (char *)shell, (char *)shell); | |
1356 | #endif | |
1357 | ||
1358 | env = do_setup_env(s, shell); | |
1359 | ||
3c0ef626 | 1360 | /* we have to stash the hostname before we close our socket. */ |
1361 | if (options.use_login) | |
1362 | hostname = get_remote_name_or_ip(utmp_len, | |
e9a17296 | 1363 | options.verify_reverse_mapping); |
3c0ef626 | 1364 | /* |
1365 | * Close the connection descriptors; note that this is the child, and | |
1366 | * the server will still have the socket open, and it is important | |
1367 | * that we do not shutdown it. Note that the descriptors cannot be | |
1368 | * closed before building the environment, as we call | |
1369 | * get_remote_ipaddr there. | |
1370 | */ | |
1371 | if (packet_get_connection_in() == packet_get_connection_out()) | |
1372 | close(packet_get_connection_in()); | |
1373 | else { | |
1374 | close(packet_get_connection_in()); | |
1375 | close(packet_get_connection_out()); | |
1376 | } | |
1377 | /* | |
1378 | * Close all descriptors related to channels. They will still remain | |
1379 | * open in the parent. | |
1380 | */ | |
1381 | /* XXX better use close-on-exec? -markus */ | |
1382 | channel_close_all(); | |
1383 | ||
1384 | /* | |
1385 | * Close any extra file descriptors. Note that there may still be | |
1386 | * descriptors left by system functions. They will be closed later. | |
1387 | */ | |
1388 | endpwent(); | |
1389 | ||
1390 | /* | |
1391 | * Close any extra open file descriptors so that we don\'t have them | |
1392 | * hanging around in clients. Note that we want to do this after | |
1393 | * initgroups, because at least on Solaris 2.3 it leaves file | |
1394 | * descriptors open. | |
1395 | */ | |
1396 | for (i = 3; i < 64; i++) | |
1397 | close(i); | |
1398 | ||
1399 | /* | |
e9a17296 | 1400 | * Must take new environment into use so that .ssh/rc, |
1401 | * /etc/ssh/sshrc and xauth are run in the proper environment. | |
3c0ef626 | 1402 | */ |
1403 | environ = env; | |
1404 | ||
1405 | #ifdef AFS | |
1406 | /* Try to get AFS tokens for the local cell. */ | |
1407 | if (k_hasafs()) { | |
1408 | char cell[64]; | |
e9a17296 | 1409 | |
3c0ef626 | 1410 | if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0) |
1411 | krb_afslog(cell, 0); | |
e9a17296 | 1412 | |
3c0ef626 | 1413 | krb_afslog(0, 0); |
1414 | } | |
1415 | #endif /* AFS */ | |
1416 | ||
1417 | /* Change current directory to the user\'s home directory. */ | |
1418 | if (chdir(pw->pw_dir) < 0) { | |
1419 | fprintf(stderr, "Could not chdir to home directory %s: %s\n", | |
1420 | pw->pw_dir, strerror(errno)); | |
1421 | #ifdef HAVE_LOGIN_CAP | |
1422 | if (login_getcapbool(lc, "requirehome", 0)) | |
1423 | exit(1); | |
1424 | #endif | |
1425 | } | |
1426 | ||
e9a17296 | 1427 | if (!options.use_login) |
1428 | do_rc_files(s, shell); | |
3c0ef626 | 1429 | |
1430 | /* restore SIGPIPE for child */ | |
1431 | signal(SIGPIPE, SIG_DFL); | |
1432 | ||
e9a17296 | 1433 | if (options.use_login) { |
2980ea68 | 1434 | launch_login(pw, hostname); |
1435 | /* NEVERREACHED */ | |
e9a17296 | 1436 | } |
1437 | ||
1438 | /* Get the last component of the shell name. */ | |
1439 | if ((shell0 = strrchr(shell, '/')) != NULL) | |
1440 | shell0++; | |
1441 | else | |
1442 | shell0 = shell; | |
1443 | ||
3c0ef626 | 1444 | /* |
1445 | * If we have no command, execute the shell. In this case, the shell | |
1446 | * name to be passed in argv[0] is preceded by '-' to indicate that | |
1447 | * this is a login shell. | |
1448 | */ | |
1449 | if (!command) { | |
e9a17296 | 1450 | char argv0[256]; |
3c0ef626 | 1451 | |
e9a17296 | 1452 | /* Start the shell. Set initial character to '-'. */ |
1453 | argv0[0] = '-'; | |
3c0ef626 | 1454 | |
e9a17296 | 1455 | if (strlcpy(argv0 + 1, shell0, sizeof(argv0) - 1) |
1456 | >= sizeof(argv0) - 1) { | |
1457 | errno = EINVAL; | |
3c0ef626 | 1458 | perror(shell); |
1459 | exit(1); | |
e9a17296 | 1460 | } |
3c0ef626 | 1461 | |
e9a17296 | 1462 | /* Execute the shell. */ |
1463 | argv[0] = argv0; | |
1464 | argv[1] = NULL; | |
1465 | execve(shell, argv, env); | |
3c0ef626 | 1466 | |
e9a17296 | 1467 | /* Executing the shell failed. */ |
1468 | perror(shell); | |
1469 | exit(1); | |
3c0ef626 | 1470 | } |
1471 | /* | |
1472 | * Execute the command using the user's shell. This uses the -c | |
1473 | * option to execute the command. | |
1474 | */ | |
e9a17296 | 1475 | argv[0] = (char *) shell0; |
3c0ef626 | 1476 | argv[1] = "-c"; |
1477 | argv[2] = (char *) command; | |
1478 | argv[3] = NULL; | |
1479 | execve(shell, argv, env); | |
1480 | perror(shell); | |
1481 | exit(1); | |
1482 | } | |
1483 | ||
1484 | Session * | |
1485 | session_new(void) | |
1486 | { | |
1487 | int i; | |
1488 | static int did_init = 0; | |
1489 | if (!did_init) { | |
1490 | debug("session_new: init"); | |
e9a17296 | 1491 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1492 | sessions[i].used = 0; |
1493 | } | |
1494 | did_init = 1; | |
1495 | } | |
e9a17296 | 1496 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1497 | Session *s = &sessions[i]; |
1498 | if (! s->used) { | |
1499 | memset(s, 0, sizeof(*s)); | |
1500 | s->chanid = -1; | |
1501 | s->ptyfd = -1; | |
1502 | s->ttyfd = -1; | |
1503 | s->used = 1; | |
1504 | s->self = i; | |
1505 | debug("session_new: session %d", i); | |
1506 | return s; | |
1507 | } | |
1508 | } | |
1509 | return NULL; | |
1510 | } | |
1511 | ||
1512 | static void | |
1513 | session_dump(void) | |
1514 | { | |
1515 | int i; | |
e9a17296 | 1516 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1517 | Session *s = &sessions[i]; |
ff2d7a98 | 1518 | debug("dump: used %d session %d %p channel %d pid %ld", |
3c0ef626 | 1519 | s->used, |
1520 | s->self, | |
1521 | s, | |
1522 | s->chanid, | |
ff2d7a98 | 1523 | (long)s->pid); |
3c0ef626 | 1524 | } |
1525 | } | |
1526 | ||
1527 | int | |
1528 | session_open(Authctxt *authctxt, int chanid) | |
1529 | { | |
1530 | Session *s = session_new(); | |
1531 | debug("session_open: channel %d", chanid); | |
1532 | if (s == NULL) { | |
1533 | error("no more sessions"); | |
1534 | return 0; | |
1535 | } | |
1536 | s->authctxt = authctxt; | |
1537 | s->pw = authctxt->pw; | |
1538 | if (s->pw == NULL) | |
1539 | fatal("no user for session %d", s->self); | |
1540 | debug("session_open: session %d: link with channel %d", s->self, chanid); | |
1541 | s->chanid = chanid; | |
1542 | return 1; | |
1543 | } | |
1544 | ||
2980ea68 | 1545 | Session * |
1546 | session_by_tty(char *tty) | |
1547 | { | |
1548 | int i; | |
1549 | for (i = 0; i < MAX_SESSIONS; i++) { | |
1550 | Session *s = &sessions[i]; | |
1551 | if (s->used && s->ttyfd != -1 && strcmp(s->tty, tty) == 0) { | |
1552 | debug("session_by_tty: session %d tty %s", i, tty); | |
1553 | return s; | |
1554 | } | |
1555 | } | |
1556 | debug("session_by_tty: unknown tty %.100s", tty); | |
1557 | session_dump(); | |
1558 | return NULL; | |
1559 | } | |
1560 | ||
3c0ef626 | 1561 | static Session * |
1562 | session_by_channel(int id) | |
1563 | { | |
1564 | int i; | |
e9a17296 | 1565 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1566 | Session *s = &sessions[i]; |
1567 | if (s->used && s->chanid == id) { | |
1568 | debug("session_by_channel: session %d channel %d", i, id); | |
1569 | return s; | |
1570 | } | |
1571 | } | |
1572 | debug("session_by_channel: unknown channel %d", id); | |
1573 | session_dump(); | |
1574 | return NULL; | |
1575 | } | |
1576 | ||
1577 | static Session * | |
1578 | session_by_pid(pid_t pid) | |
1579 | { | |
1580 | int i; | |
ff2d7a98 | 1581 | debug("session_by_pid: pid %ld", (long)pid); |
e9a17296 | 1582 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1583 | Session *s = &sessions[i]; |
1584 | if (s->used && s->pid == pid) | |
1585 | return s; | |
1586 | } | |
ff2d7a98 | 1587 | error("session_by_pid: unknown pid %ld", (long)pid); |
3c0ef626 | 1588 | session_dump(); |
1589 | return NULL; | |
1590 | } | |
1591 | ||
1592 | static int | |
1593 | session_window_change_req(Session *s) | |
1594 | { | |
1595 | s->col = packet_get_int(); | |
1596 | s->row = packet_get_int(); | |
1597 | s->xpixel = packet_get_int(); | |
1598 | s->ypixel = packet_get_int(); | |
e9a17296 | 1599 | packet_check_eom(); |
3c0ef626 | 1600 | pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel); |
1601 | return 1; | |
1602 | } | |
1603 | ||
1604 | static int | |
1605 | session_pty_req(Session *s) | |
1606 | { | |
1607 | u_int len; | |
1608 | int n_bytes; | |
1609 | ||
1610 | if (no_pty_flag) { | |
1611 | debug("Allocating a pty not permitted for this authentication."); | |
1612 | return 0; | |
1613 | } | |
1614 | if (s->ttyfd != -1) { | |
1615 | packet_disconnect("Protocol error: you already have a pty."); | |
1616 | return 0; | |
1617 | } | |
2980ea68 | 1618 | /* Get the time and hostname when the user last logged in. */ |
1619 | if (options.print_lastlog) { | |
1620 | s->hostname[0] = '\0'; | |
1621 | s->last_login_time = get_last_login_time(s->pw->pw_uid, | |
1622 | s->pw->pw_name, s->hostname, sizeof(s->hostname)); | |
1623 | } | |
3c0ef626 | 1624 | |
1625 | s->term = packet_get_string(&len); | |
1626 | ||
1627 | if (compat20) { | |
1628 | s->col = packet_get_int(); | |
1629 | s->row = packet_get_int(); | |
1630 | } else { | |
1631 | s->row = packet_get_int(); | |
1632 | s->col = packet_get_int(); | |
1633 | } | |
1634 | s->xpixel = packet_get_int(); | |
1635 | s->ypixel = packet_get_int(); | |
1636 | ||
1637 | if (strcmp(s->term, "") == 0) { | |
1638 | xfree(s->term); | |
1639 | s->term = NULL; | |
1640 | } | |
1641 | ||
1642 | /* Allocate a pty and open it. */ | |
1643 | debug("Allocating pty."); | |
2980ea68 | 1644 | if (!PRIVSEP(pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty)))) { |
3c0ef626 | 1645 | if (s->term) |
1646 | xfree(s->term); | |
1647 | s->term = NULL; | |
1648 | s->ptyfd = -1; | |
1649 | s->ttyfd = -1; | |
1650 | error("session_pty_req: session %d alloc failed", s->self); | |
1651 | return 0; | |
1652 | } | |
1653 | debug("session_pty_req: session %d alloc %s", s->self, s->tty); | |
1654 | ||
1655 | /* for SSH1 the tty modes length is not given */ | |
1656 | if (!compat20) | |
1657 | n_bytes = packet_remaining(); | |
1658 | tty_parse_modes(s->ttyfd, &n_bytes); | |
1659 | ||
1660 | /* | |
1661 | * Add a cleanup function to clear the utmp entry and record logout | |
1662 | * time in case we call fatal() (e.g., the connection gets closed). | |
1663 | */ | |
1664 | fatal_add_cleanup(session_pty_cleanup, (void *)s); | |
2980ea68 | 1665 | if (!use_privsep) |
1666 | pty_setowner(s->pw, s->tty); | |
3c0ef626 | 1667 | |
1668 | /* Set window size from the packet. */ | |
1669 | pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel); | |
1670 | ||
e9a17296 | 1671 | packet_check_eom(); |
3c0ef626 | 1672 | session_proctitle(s); |
1673 | return 1; | |
1674 | } | |
1675 | ||
1676 | static int | |
1677 | session_subsystem_req(Session *s) | |
1678 | { | |
1679 | struct stat st; | |
1680 | u_int len; | |
1681 | int success = 0; | |
1682 | char *cmd, *subsys = packet_get_string(&len); | |
1683 | int i; | |
1684 | ||
e9a17296 | 1685 | packet_check_eom(); |
1686 | log("subsystem request for %.100s", subsys); | |
3c0ef626 | 1687 | |
1688 | for (i = 0; i < options.num_subsystems; i++) { | |
1689 | if (strcmp(subsys, options.subsystem_name[i]) == 0) { | |
1690 | cmd = options.subsystem_command[i]; | |
1691 | if (stat(cmd, &st) < 0) { | |
1692 | error("subsystem: cannot stat %s: %s", cmd, | |
1693 | strerror(errno)); | |
1694 | break; | |
1695 | } | |
1696 | debug("subsystem: exec() %s", cmd); | |
1697 | s->is_subsystem = 1; | |
1698 | do_exec(s, cmd); | |
1699 | success = 1; | |
e9a17296 | 1700 | break; |
3c0ef626 | 1701 | } |
1702 | } | |
1703 | ||
1704 | if (!success) | |
e9a17296 | 1705 | log("subsystem request for %.100s failed, subsystem not found", |
3c0ef626 | 1706 | subsys); |
1707 | ||
1708 | xfree(subsys); | |
1709 | return success; | |
1710 | } | |
1711 | ||
1712 | static int | |
1713 | session_x11_req(Session *s) | |
1714 | { | |
1715 | int success; | |
1716 | ||
1717 | s->single_connection = packet_get_char(); | |
1718 | s->auth_proto = packet_get_string(NULL); | |
1719 | s->auth_data = packet_get_string(NULL); | |
1720 | s->screen = packet_get_int(); | |
e9a17296 | 1721 | packet_check_eom(); |
3c0ef626 | 1722 | |
1723 | success = session_setup_x11fwd(s); | |
1724 | if (!success) { | |
1725 | xfree(s->auth_proto); | |
1726 | xfree(s->auth_data); | |
1727 | s->auth_proto = NULL; | |
1728 | s->auth_data = NULL; | |
1729 | } | |
1730 | return success; | |
1731 | } | |
1732 | ||
1733 | static int | |
1734 | session_shell_req(Session *s) | |
1735 | { | |
e9a17296 | 1736 | packet_check_eom(); |
3c0ef626 | 1737 | do_exec(s, NULL); |
1738 | return 1; | |
1739 | } | |
1740 | ||
1741 | static int | |
1742 | session_exec_req(Session *s) | |
1743 | { | |
1744 | u_int len; | |
1745 | char *command = packet_get_string(&len); | |
e9a17296 | 1746 | packet_check_eom(); |
3c0ef626 | 1747 | do_exec(s, command); |
1748 | xfree(command); | |
1749 | return 1; | |
1750 | } | |
1751 | ||
1752 | static int | |
1753 | session_auth_agent_req(Session *s) | |
1754 | { | |
1755 | static int called = 0; | |
e9a17296 | 1756 | packet_check_eom(); |
3c0ef626 | 1757 | if (no_agent_forwarding_flag) { |
1758 | debug("session_auth_agent_req: no_agent_forwarding_flag"); | |
1759 | return 0; | |
1760 | } | |
1761 | if (called) { | |
1762 | return 0; | |
1763 | } else { | |
1764 | called = 1; | |
1765 | return auth_input_request_forwarding(s->pw); | |
1766 | } | |
1767 | } | |
1768 | ||
e9a17296 | 1769 | int |
1770 | session_input_channel_req(Channel *c, const char *rtype) | |
3c0ef626 | 1771 | { |
3c0ef626 | 1772 | int success = 0; |
3c0ef626 | 1773 | Session *s; |
3c0ef626 | 1774 | |
e9a17296 | 1775 | if ((s = session_by_channel(c->self)) == NULL) { |
1776 | log("session_input_channel_req: no session %d req %.100s", | |
1777 | c->self, rtype); | |
1778 | return 0; | |
1779 | } | |
1780 | debug("session_input_channel_req: session %d req %s", s->self, rtype); | |
3c0ef626 | 1781 | |
1782 | /* | |
1783 | * a session is in LARVAL state until a shell, a command | |
1784 | * or a subsystem is executed | |
1785 | */ | |
1786 | if (c->type == SSH_CHANNEL_LARVAL) { | |
1787 | if (strcmp(rtype, "shell") == 0) { | |
1788 | success = session_shell_req(s); | |
1789 | } else if (strcmp(rtype, "exec") == 0) { | |
1790 | success = session_exec_req(s); | |
1791 | } else if (strcmp(rtype, "pty-req") == 0) { | |
1792 | success = session_pty_req(s); | |
1793 | } else if (strcmp(rtype, "x11-req") == 0) { | |
1794 | success = session_x11_req(s); | |
1795 | } else if (strcmp(rtype, "auth-agent-req@openssh.com") == 0) { | |
1796 | success = session_auth_agent_req(s); | |
1797 | } else if (strcmp(rtype, "subsystem") == 0) { | |
1798 | success = session_subsystem_req(s); | |
1799 | } | |
1800 | } | |
1801 | if (strcmp(rtype, "window-change") == 0) { | |
1802 | success = session_window_change_req(s); | |
1803 | } | |
e9a17296 | 1804 | return success; |
3c0ef626 | 1805 | } |
1806 | ||
1807 | void | |
1808 | session_set_fds(Session *s, int fdin, int fdout, int fderr) | |
1809 | { | |
1810 | if (!compat20) | |
1811 | fatal("session_set_fds: called for proto != 2.0"); | |
1812 | /* | |
1813 | * now that have a child and a pipe to the child, | |
1814 | * we can activate our channel and register the fd's | |
1815 | */ | |
1816 | if (s->chanid == -1) | |
1817 | fatal("no channel for session %d", s->self); | |
1818 | channel_set_fds(s->chanid, | |
1819 | fdout, fdin, fderr, | |
1820 | fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ, | |
e9a17296 | 1821 | 1, |
1822 | CHAN_SES_WINDOW_DEFAULT); | |
3c0ef626 | 1823 | } |
1824 | ||
1825 | /* | |
1826 | * Function to perform pty cleanup. Also called if we get aborted abnormally | |
1827 | * (e.g., due to a dropped connection). | |
1828 | */ | |
2980ea68 | 1829 | void |
1830 | session_pty_cleanup2(void *session) | |
3c0ef626 | 1831 | { |
1832 | Session *s = session; | |
1833 | ||
1834 | if (s == NULL) { | |
1835 | error("session_pty_cleanup: no session"); | |
1836 | return; | |
1837 | } | |
1838 | if (s->ttyfd == -1) | |
1839 | return; | |
1840 | ||
1841 | debug("session_pty_cleanup: session %d release %s", s->self, s->tty); | |
1842 | ||
1843 | /* Record that the user has logged out. */ | |
1844 | if (s->pid != 0) | |
e9a17296 | 1845 | record_logout(s->pid, s->tty, s->pw->pw_name); |
3c0ef626 | 1846 | |
1847 | /* Release the pseudo-tty. */ | |
2980ea68 | 1848 | if (getuid() == 0) |
1849 | pty_release(s->tty); | |
3c0ef626 | 1850 | |
1851 | /* | |
1852 | * Close the server side of the socket pairs. We must do this after | |
1853 | * the pty cleanup, so that another process doesn't get this pty | |
1854 | * while we're still cleaning up. | |
1855 | */ | |
1856 | if (close(s->ptymaster) < 0) | |
2980ea68 | 1857 | error("close(s->ptymaster/%d): %s", s->ptymaster, strerror(errno)); |
3c0ef626 | 1858 | |
1859 | /* unlink pty from session */ | |
1860 | s->ttyfd = -1; | |
1861 | } | |
1862 | ||
2980ea68 | 1863 | void |
1864 | session_pty_cleanup(void *session) | |
1865 | { | |
1866 | PRIVSEP(session_pty_cleanup2(session)); | |
1867 | } | |
1868 | ||
e54b3d7c | 1869 | static char * |
1870 | sig2name(int sig) | |
1871 | { | |
1872 | #define SSH_SIG(x) if (sig == SIG ## x) return #x | |
1873 | SSH_SIG(ABRT); | |
1874 | SSH_SIG(ALRM); | |
1875 | SSH_SIG(FPE); | |
1876 | SSH_SIG(HUP); | |
1877 | SSH_SIG(ILL); | |
1878 | SSH_SIG(INT); | |
1879 | SSH_SIG(KILL); | |
1880 | SSH_SIG(PIPE); | |
1881 | SSH_SIG(QUIT); | |
1882 | SSH_SIG(SEGV); | |
1883 | SSH_SIG(TERM); | |
1884 | SSH_SIG(USR1); | |
1885 | SSH_SIG(USR2); | |
1886 | #undef SSH_SIG | |
1887 | return "SIG@openssh.com"; | |
1888 | } | |
1889 | ||
3c0ef626 | 1890 | static void |
1891 | session_exit_message(Session *s, int status) | |
1892 | { | |
1893 | Channel *c; | |
e9a17296 | 1894 | |
1895 | if ((c = channel_lookup(s->chanid)) == NULL) | |
3c0ef626 | 1896 | fatal("session_exit_message: session %d: no channel %d", |
1897 | s->self, s->chanid); | |
ff2d7a98 | 1898 | debug("session_exit_message: session %d channel %d pid %ld", |
1899 | s->self, s->chanid, (long)s->pid); | |
3c0ef626 | 1900 | |
1901 | if (WIFEXITED(status)) { | |
e9a17296 | 1902 | channel_request_start(s->chanid, "exit-status", 0); |
3c0ef626 | 1903 | packet_put_int(WEXITSTATUS(status)); |
1904 | packet_send(); | |
1905 | } else if (WIFSIGNALED(status)) { | |
e9a17296 | 1906 | channel_request_start(s->chanid, "exit-signal", 0); |
e54b3d7c | 1907 | packet_put_cstring(sig2name(WTERMSIG(status))); |
3c0ef626 | 1908 | #ifdef WCOREDUMP |
1909 | packet_put_char(WCOREDUMP(status)); | |
1910 | #else /* WCOREDUMP */ | |
1911 | packet_put_char(0); | |
1912 | #endif /* WCOREDUMP */ | |
1913 | packet_put_cstring(""); | |
1914 | packet_put_cstring(""); | |
1915 | packet_send(); | |
1916 | } else { | |
1917 | /* Some weird exit cause. Just exit. */ | |
1918 | packet_disconnect("wait returned status %04x.", status); | |
1919 | } | |
1920 | ||
1921 | /* disconnect channel */ | |
1922 | debug("session_exit_message: release channel %d", s->chanid); | |
1923 | channel_cancel_cleanup(s->chanid); | |
1924 | /* | |
1925 | * emulate a write failure with 'chan_write_failed', nobody will be | |
1926 | * interested in data we write. | |
1927 | * Note that we must not call 'chan_read_failed', since there could | |
1928 | * be some more data waiting in the pipe. | |
1929 | */ | |
1930 | if (c->ostate != CHAN_OUTPUT_CLOSED) | |
1931 | chan_write_failed(c); | |
1932 | s->chanid = -1; | |
1933 | } | |
1934 | ||
2980ea68 | 1935 | void |
3c0ef626 | 1936 | session_close(Session *s) |
1937 | { | |
ff2d7a98 | 1938 | debug("session_close: session %d pid %ld", s->self, (long)s->pid); |
3c0ef626 | 1939 | if (s->ttyfd != -1) { |
1940 | fatal_remove_cleanup(session_pty_cleanup, (void *)s); | |
1941 | session_pty_cleanup(s); | |
1942 | } | |
1943 | if (s->term) | |
1944 | xfree(s->term); | |
1945 | if (s->display) | |
1946 | xfree(s->display); | |
e9a17296 | 1947 | if (s->auth_display) |
1948 | xfree(s->auth_display); | |
3c0ef626 | 1949 | if (s->auth_data) |
1950 | xfree(s->auth_data); | |
1951 | if (s->auth_proto) | |
1952 | xfree(s->auth_proto); | |
1953 | s->used = 0; | |
1954 | session_proctitle(s); | |
1955 | } | |
1956 | ||
1957 | void | |
1958 | session_close_by_pid(pid_t pid, int status) | |
1959 | { | |
1960 | Session *s = session_by_pid(pid); | |
1961 | if (s == NULL) { | |
ff2d7a98 | 1962 | debug("session_close_by_pid: no session for pid %ld", |
1963 | (long)pid); | |
3c0ef626 | 1964 | return; |
1965 | } | |
1966 | if (s->chanid != -1) | |
1967 | session_exit_message(s, status); | |
1968 | session_close(s); | |
1969 | } | |
1970 | ||
1971 | /* | |
1972 | * this is called when a channel dies before | |
1973 | * the session 'child' itself dies | |
1974 | */ | |
1975 | void | |
1976 | session_close_by_channel(int id, void *arg) | |
1977 | { | |
1978 | Session *s = session_by_channel(id); | |
1979 | if (s == NULL) { | |
1980 | debug("session_close_by_channel: no session for id %d", id); | |
1981 | return; | |
1982 | } | |
ff2d7a98 | 1983 | debug("session_close_by_channel: channel %d child %ld", |
1984 | id, (long)s->pid); | |
3c0ef626 | 1985 | if (s->pid != 0) { |
1986 | debug("session_close_by_channel: channel %d: has child", id); | |
1987 | /* | |
1988 | * delay detach of session, but release pty, since | |
1989 | * the fd's to the child are already closed | |
1990 | */ | |
1991 | if (s->ttyfd != -1) { | |
1992 | fatal_remove_cleanup(session_pty_cleanup, (void *)s); | |
1993 | session_pty_cleanup(s); | |
1994 | } | |
1995 | return; | |
1996 | } | |
1997 | /* detach by removing callback */ | |
1998 | channel_cancel_cleanup(s->chanid); | |
1999 | s->chanid = -1; | |
2000 | session_close(s); | |
2001 | } | |
2002 | ||
2003 | void | |
2980ea68 | 2004 | session_destroy_all(void (*closefunc)(Session *)) |
3c0ef626 | 2005 | { |
2006 | int i; | |
e9a17296 | 2007 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 2008 | Session *s = &sessions[i]; |
2980ea68 | 2009 | if (s->used) { |
2010 | if (closefunc != NULL) | |
2011 | closefunc(s); | |
2012 | else | |
2013 | session_close(s); | |
2014 | } | |
3c0ef626 | 2015 | } |
2016 | } | |
2017 | ||
2018 | static char * | |
2019 | session_tty_list(void) | |
2020 | { | |
2021 | static char buf[1024]; | |
2022 | int i; | |
2023 | buf[0] = '\0'; | |
e9a17296 | 2024 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 2025 | Session *s = &sessions[i]; |
2026 | if (s->used && s->ttyfd != -1) { | |
2027 | if (buf[0] != '\0') | |
2028 | strlcat(buf, ",", sizeof buf); | |
2029 | strlcat(buf, strrchr(s->tty, '/') + 1, sizeof buf); | |
2030 | } | |
2031 | } | |
2032 | if (buf[0] == '\0') | |
2033 | strlcpy(buf, "notty", sizeof buf); | |
2034 | return buf; | |
2035 | } | |
2036 | ||
2037 | void | |
2038 | session_proctitle(Session *s) | |
2039 | { | |
2040 | if (s->pw == NULL) | |
2041 | error("no user for session %d", s->self); | |
2042 | else | |
2043 | setproctitle("%s@%s", s->pw->pw_name, session_tty_list()); | |
2044 | } | |
2045 | ||
2046 | int | |
2047 | session_setup_x11fwd(Session *s) | |
2048 | { | |
2049 | struct stat st; | |
e9a17296 | 2050 | char display[512], auth_display[512]; |
2051 | char hostname[MAXHOSTNAMELEN]; | |
3c0ef626 | 2052 | |
2053 | if (no_x11_forwarding_flag) { | |
2054 | packet_send_debug("X11 forwarding disabled in user configuration file."); | |
2055 | return 0; | |
2056 | } | |
2057 | if (!options.x11_forwarding) { | |
2058 | debug("X11 forwarding disabled in server configuration file."); | |
2059 | return 0; | |
2060 | } | |
2061 | if (!options.xauth_location || | |
2062 | (stat(options.xauth_location, &st) == -1)) { | |
2063 | packet_send_debug("No xauth program; cannot forward with spoofing."); | |
2064 | return 0; | |
2065 | } | |
2066 | if (options.use_login) { | |
2067 | packet_send_debug("X11 forwarding disabled; " | |
2068 | "not compatible with UseLogin=yes."); | |
2069 | return 0; | |
2070 | } | |
2071 | if (s->display != NULL) { | |
2072 | debug("X11 display already set."); | |
2073 | return 0; | |
2074 | } | |
ff2d7a98 | 2075 | if (x11_create_display_inet(options.x11_display_offset, |
2076 | options.x11_use_localhost, s->single_connection, | |
2077 | &s->display_number) == -1) { | |
3c0ef626 | 2078 | debug("x11_create_display_inet failed."); |
2079 | return 0; | |
2080 | } | |
e9a17296 | 2081 | |
2082 | /* Set up a suitable value for the DISPLAY variable. */ | |
2083 | if (gethostname(hostname, sizeof(hostname)) < 0) | |
2084 | fatal("gethostname: %.100s", strerror(errno)); | |
2085 | /* | |
2086 | * auth_display must be used as the displayname when the | |
2087 | * authorization entry is added with xauth(1). This will be | |
2088 | * different than the DISPLAY string for localhost displays. | |
2089 | */ | |
2090 | if (options.x11_use_localhost) { | |
ff2d7a98 | 2091 | snprintf(display, sizeof display, "localhost:%u.%u", |
e9a17296 | 2092 | s->display_number, s->screen); |
ff2d7a98 | 2093 | snprintf(auth_display, sizeof auth_display, "unix:%u.%u", |
e9a17296 | 2094 | s->display_number, s->screen); |
2095 | s->display = xstrdup(display); | |
2096 | s->auth_display = xstrdup(auth_display); | |
2097 | } else { | |
2098 | #ifdef IPADDR_IN_DISPLAY | |
2099 | struct hostent *he; | |
2100 | struct in_addr my_addr; | |
2101 | ||
2102 | he = gethostbyname(hostname); | |
2103 | if (he == NULL) { | |
2104 | error("Can't get IP address for X11 DISPLAY."); | |
2105 | packet_send_debug("Can't get IP address for X11 DISPLAY."); | |
2106 | return 0; | |
2107 | } | |
2108 | memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr)); | |
ff2d7a98 | 2109 | snprintf(display, sizeof display, "%.50s:%u.%u", inet_ntoa(my_addr), |
e9a17296 | 2110 | s->display_number, s->screen); |
2111 | #else | |
ff2d7a98 | 2112 | snprintf(display, sizeof display, "%.400s:%u.%u", hostname, |
e9a17296 | 2113 | s->display_number, s->screen); |
2114 | #endif | |
2115 | s->display = xstrdup(display); | |
2116 | s->auth_display = xstrdup(display); | |
2117 | } | |
2118 | ||
3c0ef626 | 2119 | return 1; |
2120 | } | |
2121 | ||
2122 | static void | |
2123 | do_authenticated2(Authctxt *authctxt) | |
2124 | { | |
2125 | server_loop2(authctxt); | |
b9a54c29 | 2126 | #if defined(GSSAPI) |
2127 | ssh_gssapi_cleanup_creds(NULL); | |
2128 | #endif | |
3c0ef626 | 2129 | } |