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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" | |
e00da40d | 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" | |
1b56ff3d | 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" | |
34fee935 | 59 | #include "kex.h" |
2980ea68 | 60 | #include "monitor_wrap.h" |
3c0ef626 | 61 | |
416fd2a8 | 62 | #if defined(KRB5) && defined(USE_AFS) |
63 | #include <kafs.h> | |
64 | #endif | |
65 | ||
b9a54c29 | 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); | |
416fd2a8 | 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 | ||
88928908 | 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); | |
70791e56 | 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 |
2980ea68 | 116 | login_cap_t *lc; |
3c0ef626 | 117 | #endif |
118 | ||
416fd2a8 | 119 | static int is_child = 0; |
120 | ||
ff2d7a98 | 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 | |
416fd2a8 | 128 | auth_sock_cleanup_proc(struct passwd *pw) |
ff2d7a98 | 129 | { |
ff2d7a98 | 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); | |
416fd2a8 | 157 | strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN); |
ff2d7a98 | 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 | ||
ff2d7a98 | 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. */ | |
416fd2a8 | 190 | if (listen(sock, SSH_LISTEN_BACKLOG) < 0) |
ff2d7a98 | 191 | packet_disconnect("listen: %.100s", strerror(errno)); |
192 | ||
193 | /* Allocate a channel for the authentication agent socket. */ | |
e00da40d | 194 | /* this shouldn't matter if its hpn or not - cjr */ |
ff2d7a98 | 195 | nc = channel_new("auth socket", |
196 | SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1, | |
197 | CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, | |
70791e56 | 198 | 0, "auth socket", 1); |
ff2d7a98 | 199 | strlcpy(nc->path, auth_sock_name, sizeof(nc->path)); |
200 | return 1; | |
201 | } | |
202 | ||
416fd2a8 | 203 | static void |
204 | display_loginmsg(void) | |
205 | { | |
34fee935 | 206 | if (buffer_len(&loginmsg) > 0) { |
207 | buffer_append(&loginmsg, "\0", 1); | |
208 | printf("%s", (char *)buffer_ptr(&loginmsg)); | |
209 | buffer_clear(&loginmsg); | |
210 | } | |
416fd2a8 | 211 | } |
ff2d7a98 | 212 | |
3c0ef626 | 213 | void |
214 | do_authenticated(Authctxt *authctxt) | |
215 | { | |
1c14df9e | 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 | ||
88928908 | 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 | |
416fd2a8 | 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; | |
e9a17296 | 256 | int success, type, screen_flag; |
ff2d7a98 | 257 | int enable_compression_after_reply = 0; |
258 | u_int proto_len, data_len, dlen, compression_level = 0; | |
3c0ef626 | 259 | |
260 | s = session_new(); | |
34fee935 | 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. */ | |
e9a17296 | 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(); |
e9a17296 | 282 | packet_check_eom(); |
3c0ef626 | 283 | if (compression_level < 1 || compression_level > 9) { |
1b56ff3d | 284 | packet_send_debug("Received invalid compression level %d.", |
e9a17296 | 285 | compression_level); |
3c0ef626 | 286 | break; |
287 | } | |
34fee935 | 288 | if (options.compression == COMP_NONE) { |
ff2d7a98 | 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 | } | |
e9a17296 | 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."); | |
e00da40d | 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; | |
e9a17296 | 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 | } | |
e9a17296 | 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 | */ | |
70791e56 | 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 | { | |
ff2d7a98 | 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) | |
416fd2a8 | 420 | if (options.use_pam && !use_privsep) |
70791e56 | 421 | do_pam_setcred(1); |
3c0ef626 | 422 | #endif /* USE_PAM */ |
423 | ||
424 | /* Fork the child. */ | |
425 | if ((pid = fork()) == 0) { | |
416fd2a8 | 426 | is_child = 1; |
e54b3d7c | 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 | ||
e54b3d7c | 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 | } | |
e54b3d7c | 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) { | |
1b56ff3d | 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 | ||
2a304a95 | 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) | |
70791e56 | 555 | if (options.use_pam) { |
556 | do_pam_set_tty(s->tty); | |
416fd2a8 | 557 | if (!use_privsep) |
558 | do_pam_setcred(1); | |
70791e56 | 559 | } |
3c0ef626 | 560 | #endif |
561 | ||
562 | /* Fork the child. */ | |
563 | if ((pid = fork()) == 0) { | |
416fd2a8 | 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 | |
e54b3d7c | 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); |
e54b3d7c | 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 | } | |
e54b3d7c | 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)); | |
e54b3d7c | 655 | fromlen = sizeof(from); |
3c0ef626 | 656 | if (packet_connection_is_on_socket()) { |
3c0ef626 | 657 | if (getpeername(packet_get_connection_in(), |
e9a17296 | 658 | (struct sockaddr *) & from, &fromlen) < 0) { |
3c0ef626 | 659 | debug("getpeername: %.100s", strerror(errno)); |
416fd2a8 | 660 | cleanup_exit(255); |
3c0ef626 | 661 | } |
662 | } | |
663 | ||
664 | record_utmp_only(pid, s->tty, s->pw->pw_name, | |
70791e56 | 665 | get_remote_name_or_ip(utmp_len, options.use_dns), |
1c14df9e | 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 | ||
70791e56 | 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 | ||
34fee935 | 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)); | |
70791e56 | 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 | |
1b56ff3d | 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 | } | |
e9a17296 | 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)); | |
1c14df9e | 744 | fromlen = sizeof(from); |
3c0ef626 | 745 | if (packet_connection_is_on_socket()) { |
3c0ef626 | 746 | if (getpeername(packet_get_connection_in(), |
e9a17296 | 747 | (struct sockaddr *) & from, &fromlen) < 0) { |
3c0ef626 | 748 | debug("getpeername: %.100s", strerror(errno)); |
416fd2a8 | 749 | cleanup_exit(255); |
3c0ef626 | 750 | } |
751 | } | |
752 | ||
3c0ef626 | 753 | /* Record that there was a login on that tty from the remote host. */ |
2980ea68 | 754 | if (!use_privsep) |
755 | record_login(pid, s->tty, pw->pw_name, pw->pw_uid, | |
756 | get_remote_name_or_ip(utmp_len, | |
70791e56 | 757 | options.use_dns), |
e54b3d7c | 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 | */ | |
416fd2a8 | 765 | if (options.use_pam && !use_privsep && s->authctxt->force_pwchange) { |
766 | display_loginmsg(); | |
3c0ef626 | 767 | do_pam_chauthtok(); |
416fd2a8 | 768 | s->authctxt->force_pwchange = 0; |
70791e56 | 769 | /* XXX - signal [net] parent to enable forwardings */ |
3c0ef626 | 770 | } |
771 | #endif | |
772 | ||
773 | if (check_quietlogin(s, command)) | |
774 | return; | |
775 | ||
416fd2a8 | 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 | */ | |
b9a54c29 | 834 | void |
3c0ef626 | 835 | child_set_env(char ***envp, u_int *envsizep, const char *name, |
e9a17296 | 836 | const char *value) |
3c0ef626 | 837 | { |
3c0ef626 | 838 | char **env; |
70791e56 | 839 | u_int envsize; |
840 | u_int i, namelen; | |
841 | ||
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 | } | |
3c0ef626 | 851 | |
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. */ | |
70791e56 | 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, | |
e9a17296 | 892 | const char *filename) |
3c0ef626 | 893 | { |
894 | FILE *f; | |
895 | char buf[4096]; | |
896 | char *cp, *value; | |
ff2d7a98 | 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)) { | |
ff2d7a98 | 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) { | |
ff2d7a98 | 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 | ||
88928908 | 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 | ||
70791e56 | 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; | |
1065 | u_int i, tmpenvsize = 0; | |
416fd2a8 | 1066 | u_long mask; |
70791e56 | 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 | ||
1075 | if (tmpenv == NULL) | |
1076 | return; | |
1077 | ||
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); | |
416fd2a8 | 1084 | |
70791e56 | 1085 | if ((var = child_get_env(tmpenv, "UMASK")) != NULL) |
1086 | if (sscanf(var, "%5lo", &mask) == 1) | |
416fd2a8 | 1087 | umask((mode_t)mask); |
1088 | ||
70791e56 | 1089 | for (i = 0; tmpenv[i] != NULL; i++) |
1090 | xfree(tmpenv[i]); | |
1091 | xfree(tmpenv); | |
1092 | } | |
1093 | #endif /* HAVE_ETC_DEFAULT_LOGIN */ | |
1094 | ||
34fee935 | 1095 | void |
1096 | copy_environment(char **source, char ***env, u_int *envsize) | |
3c0ef626 | 1097 | { |
e9a17296 | 1098 | char *var_name, *var_val; |
3c0ef626 | 1099 | int i; |
1100 | ||
e9a17296 | 1101 | if (source == NULL) |
3c0ef626 | 1102 | return; |
1103 | ||
e9a17296 | 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 | } |
e9a17296 | 1110 | *var_val++ = '\0'; |
3c0ef626 | 1111 | |
e9a17296 | 1112 | debug3("Copy environment: %s=%s", var_name, var_val); |
1113 | child_set_env(env, envsize, var_name, var_val); | |
416fd2a8 | 1114 | |
e9a17296 | 1115 | xfree(var_name); |
3c0ef626 | 1116 | } |
1117 | } | |
3c0ef626 | 1118 | |
e9a17296 | 1119 | static char ** |
1120 | do_setup_env(Session *s, const char *shell) | |
3c0ef626 | 1121 | { |
3c0ef626 | 1122 | char buf[256]; |
e9a17296 | 1123 | u_int i, envsize; |
70791e56 | 1124 | char **env, *laddr, *path = NULL; |
e9a17296 | 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 | */ | |
34fee935 | 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 | ||
b9a54c29 | 1146 | #ifdef GSSAPI |
416fd2a8 | 1147 | /* Allow any GSSAPI methods that we've used to alter |
b9a54c29 | 1148 | * the childs environment as they see fit |
1149 | */ | |
70791e56 | 1150 | ssh_gssapi_do_child(&env, &envsize); |
b9a54c29 | 1151 | #endif |
1152 | ||
3c0ef626 | 1153 | if (!options.use_login) { |
1154 | /* Set basic environment. */ | |
1b56ff3d | 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); | |
1c14df9e | 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 | |
e54b3d7c | 1166 | if (setusercontext(lc, pw, pw->pw_uid, LOGIN_SETPATH) < 0) |
70791e56 | 1167 | child_set_env(&env, &envsize, "PATH", |
1168 | _PATH_STDPATH_WITH_SCP); | |
e54b3d7c | 1169 | else |
1170 | child_set_env(&env, &envsize, "PATH", getenv("PATH")); | |
3c0ef626 | 1171 | #else /* HAVE_LOGIN_CAP */ |
1172 | # ifndef HAVE_CYGWIN | |
1173 | /* | |
1174 | * There's no standard path on Windows. The path contains | |
1175 | * important components pointing to the system directories, | |
1176 | * needed for loading shared libraries. So the path better | |
1177 | * remains intact here. | |
1178 | */ | |
70791e56 | 1179 | # ifdef HAVE_ETC_DEFAULT_LOGIN |
1180 | read_etc_default_login(&env, &envsize, pw->pw_uid); | |
1181 | path = child_get_env(env, "PATH"); | |
1182 | # endif /* HAVE_ETC_DEFAULT_LOGIN */ | |
1183 | if (path == NULL || *path == '\0') { | |
416fd2a8 | 1184 | child_set_env(&env, &envsize, "PATH", |
70791e56 | 1185 | s->pw->pw_uid == 0 ? |
1186 | SUPERUSER_PATH : _PATH_STDPATH_WITH_SCP); | |
1187 | } | |
3c0ef626 | 1188 | # endif /* HAVE_CYGWIN */ |
1189 | #endif /* HAVE_LOGIN_CAP */ | |
1190 | ||
1191 | snprintf(buf, sizeof buf, "%.200s/%.50s", | |
1192 | _PATH_MAILDIR, pw->pw_name); | |
1193 | child_set_env(&env, &envsize, "MAIL", buf); | |
1194 | ||
1195 | /* Normal systems set SHELL by default. */ | |
1196 | child_set_env(&env, &envsize, "SHELL", shell); | |
1197 | } | |
1198 | if (getenv("TZ")) | |
1199 | child_set_env(&env, &envsize, "TZ", getenv("TZ")); | |
1200 | ||
2a304a95 | 1201 | #ifdef GSI /* GSI shared libs typically installed in non-system locations. */ |
1202 | { | |
1203 | char *cp; | |
1204 | ||
1205 | if ((cp = getenv("LD_LIBRARY_PATH")) != NULL) | |
1206 | child_set_env(&env, &envsize, "LD_LIBRARY_PATH", cp); | |
1207 | if ((cp = getenv("LIBPATH")) != NULL) | |
1208 | child_set_env(&env, &envsize, "LIBPATH", cp); | |
1209 | if ((cp = getenv("SHLIB_PATH")) != NULL) | |
1210 | child_set_env(&env, &envsize, "SHLIB_PATH", cp); | |
1211 | if ((cp = getenv("LD_LIBRARYN32_PATH")) != NULL) | |
1212 | child_set_env(&env, &envsize, "LD_LIBRARYN32_PATH",cp); | |
1213 | if ((cp = getenv("LD_LIBRARY64_PATH")) != NULL) | |
1214 | child_set_env(&env, &envsize, "LD_LIBRARY64_PATH",cp); | |
1215 | if ((cp = getenv("GLOBUS_LOCATION")) != NULL) | |
1216 | child_set_env(&env, &envsize, "GLOBUS_LOCATION",cp); | |
1217 | } | |
93f82cab | 1218 | #endif |
1219 | ||
3c0ef626 | 1220 | /* Set custom environment options from RSA authentication. */ |
1221 | if (!options.use_login) { | |
1222 | while (custom_environment) { | |
1223 | struct envstring *ce = custom_environment; | |
e54b3d7c | 1224 | char *str = ce->s; |
e9a17296 | 1225 | |
e54b3d7c | 1226 | for (i = 0; str[i] != '=' && str[i]; i++) |
3c0ef626 | 1227 | ; |
e54b3d7c | 1228 | if (str[i] == '=') { |
1229 | str[i] = 0; | |
1230 | child_set_env(&env, &envsize, str, str + i + 1); | |
3c0ef626 | 1231 | } |
1232 | custom_environment = ce->next; | |
1233 | xfree(ce->s); | |
1234 | xfree(ce); | |
1235 | } | |
1236 | } | |
1237 | ||
e54b3d7c | 1238 | /* SSH_CLIENT deprecated */ |
3c0ef626 | 1239 | snprintf(buf, sizeof buf, "%.50s %d %d", |
e9a17296 | 1240 | get_remote_ipaddr(), get_remote_port(), get_local_port()); |
3c0ef626 | 1241 | child_set_env(&env, &envsize, "SSH_CLIENT", buf); |
1242 | ||
1c14df9e | 1243 | laddr = get_local_ipaddr(packet_get_connection_in()); |
e54b3d7c | 1244 | snprintf(buf, sizeof buf, "%.50s %d %.50s %d", |
1c14df9e | 1245 | get_remote_ipaddr(), get_remote_port(), laddr, get_local_port()); |
1246 | xfree(laddr); | |
e54b3d7c | 1247 | child_set_env(&env, &envsize, "SSH_CONNECTION", buf); |
1248 | ||
3c0ef626 | 1249 | if (s->ttyfd != -1) |
1250 | child_set_env(&env, &envsize, "SSH_TTY", s->tty); | |
1251 | if (s->term) | |
1252 | child_set_env(&env, &envsize, "TERM", s->term); | |
1253 | if (s->display) | |
1254 | child_set_env(&env, &envsize, "DISPLAY", s->display); | |
1255 | if (original_command) | |
1256 | child_set_env(&env, &envsize, "SSH_ORIGINAL_COMMAND", | |
1257 | original_command); | |
1258 | ||
e54b3d7c | 1259 | #ifdef _UNICOS |
1260 | if (cray_tmpdir[0] != '\0') | |
1261 | child_set_env(&env, &envsize, "TMPDIR", cray_tmpdir); | |
1262 | #endif /* _UNICOS */ | |
1263 | ||
34fee935 | 1264 | /* |
1265 | * Since we clear KRB5CCNAME at startup, if it's set now then it | |
1266 | * must have been set by a native authentication method (eg AIX or | |
1267 | * SIA), so copy it to the child. | |
1268 | */ | |
1269 | { | |
1270 | char *cp; | |
1271 | ||
1272 | if ((cp = getenv("KRB5CCNAME")) != NULL) | |
1273 | child_set_env(&env, &envsize, "KRB5CCNAME", cp); | |
1274 | } | |
1275 | ||
3c0ef626 | 1276 | #ifdef _AIX |
e9a17296 | 1277 | { |
1278 | char *cp; | |
1279 | ||
1280 | if ((cp = getenv("AUTHSTATE")) != NULL) | |
1281 | child_set_env(&env, &envsize, "AUTHSTATE", cp); | |
e9a17296 | 1282 | read_environment_file(&env, &envsize, "/etc/environment"); |
1283 | } | |
3c0ef626 | 1284 | #endif |
3c0ef626 | 1285 | #ifdef KRB5 |
2a304a95 | 1286 | if (s->authctxt->krb5_ccname) |
3c0ef626 | 1287 | child_set_env(&env, &envsize, "KRB5CCNAME", |
2a304a95 | 1288 | s->authctxt->krb5_ccname); |
3c0ef626 | 1289 | #endif |
1290 | #ifdef USE_PAM | |
e54b3d7c | 1291 | /* |
1292 | * Pull in any environment variables that may have | |
1293 | * been set by PAM. | |
1294 | */ | |
70791e56 | 1295 | if (options.use_pam) { |
416fd2a8 | 1296 | char **p; |
1297 | ||
1298 | p = fetch_pam_child_environment(); | |
1299 | copy_environment(p, &env, &envsize); | |
1300 | free_pam_environment(p); | |
e54b3d7c | 1301 | |
416fd2a8 | 1302 | p = fetch_pam_environment(); |
e54b3d7c | 1303 | copy_environment(p, &env, &envsize); |
1304 | free_pam_environment(p); | |
1305 | } | |
3c0ef626 | 1306 | #endif /* USE_PAM */ |
1307 | ||
ff2d7a98 | 1308 | if (auth_sock_name != NULL) |
3c0ef626 | 1309 | child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME, |
ff2d7a98 | 1310 | auth_sock_name); |
3c0ef626 | 1311 | |
1312 | /* read $HOME/.ssh/environment. */ | |
e54b3d7c | 1313 | if (options.permit_user_env && !options.use_login) { |
3c0ef626 | 1314 | snprintf(buf, sizeof buf, "%.200s/.ssh/environment", |
e54b3d7c | 1315 | strcmp(pw->pw_dir, "/") ? pw->pw_dir : ""); |
3c0ef626 | 1316 | read_environment_file(&env, &envsize, buf); |
1317 | } | |
1318 | if (debug_flag) { | |
1319 | /* dump the environment */ | |
1320 | fprintf(stderr, "Environment:\n"); | |
1321 | for (i = 0; env[i]; i++) | |
1322 | fprintf(stderr, " %.200s\n", env[i]); | |
1323 | } | |
e9a17296 | 1324 | return env; |
1325 | } | |
1326 | ||
1327 | /* | |
1328 | * Run $HOME/.ssh/rc, /etc/ssh/sshrc, or xauth (whichever is found | |
1329 | * first in this order). | |
1330 | */ | |
1331 | static void | |
1332 | do_rc_files(Session *s, const char *shell) | |
1333 | { | |
1334 | FILE *f = NULL; | |
1335 | char cmd[1024]; | |
1336 | int do_xauth; | |
1337 | struct stat st; | |
1338 | ||
1339 | do_xauth = | |
1340 | s->display != NULL && s->auth_proto != NULL && s->auth_data != NULL; | |
1341 | ||
1342 | /* ignore _PATH_SSH_USER_RC for subsystems */ | |
1343 | if (!s->is_subsystem && (stat(_PATH_SSH_USER_RC, &st) >= 0)) { | |
1344 | snprintf(cmd, sizeof cmd, "%s -c '%s %s'", | |
1345 | shell, _PATH_BSHELL, _PATH_SSH_USER_RC); | |
1346 | if (debug_flag) | |
1347 | fprintf(stderr, "Running %s\n", cmd); | |
1348 | f = popen(cmd, "w"); | |
1349 | if (f) { | |
1350 | if (do_xauth) | |
1351 | fprintf(f, "%s %s\n", s->auth_proto, | |
1352 | s->auth_data); | |
1353 | pclose(f); | |
1354 | } else | |
1355 | fprintf(stderr, "Could not run %s\n", | |
1356 | _PATH_SSH_USER_RC); | |
1357 | } else if (stat(_PATH_SSH_SYSTEM_RC, &st) >= 0) { | |
ae43c103 | 1358 | snprintf(cmd, sizeof cmd, "%s %s", _PATH_BSHELL, |
1359 | _PATH_SSH_SYSTEM_RC); | |
e9a17296 | 1360 | if (debug_flag) |
ae43c103 | 1361 | fprintf(stderr, "Running %s\n", cmd); |
1362 | f = popen(cmd, "w"); | |
e9a17296 | 1363 | if (f) { |
1364 | if (do_xauth) | |
1365 | fprintf(f, "%s %s\n", s->auth_proto, | |
1366 | s->auth_data); | |
1367 | pclose(f); | |
1368 | } else | |
1369 | fprintf(stderr, "Could not run %s\n", | |
1370 | _PATH_SSH_SYSTEM_RC); | |
1371 | } else if (do_xauth && options.xauth_location != NULL) { | |
1372 | /* Add authority data to .Xauthority if appropriate. */ | |
1373 | if (debug_flag) { | |
1374 | fprintf(stderr, | |
1c14df9e | 1375 | "Running %.500s remove %.100s\n", |
416fd2a8 | 1376 | options.xauth_location, s->auth_display); |
1c14df9e | 1377 | fprintf(stderr, |
1378 | "%.500s add %.100s %.100s %.100s\n", | |
e9a17296 | 1379 | options.xauth_location, s->auth_display, |
1380 | s->auth_proto, s->auth_data); | |
1381 | } | |
1382 | snprintf(cmd, sizeof cmd, "%s -q -", | |
1383 | options.xauth_location); | |
1384 | f = popen(cmd, "w"); | |
1385 | if (f) { | |
1c14df9e | 1386 | fprintf(f, "remove %s\n", |
1387 | s->auth_display); | |
e9a17296 | 1388 | fprintf(f, "add %s %s %s\n", |
1389 | s->auth_display, s->auth_proto, | |
1390 | s->auth_data); | |
1391 | pclose(f); | |
1392 | } else { | |
1393 | fprintf(stderr, "Could not run %s\n", | |
1394 | cmd); | |
1395 | } | |
1396 | } | |
1397 | } | |
1398 | ||
1399 | static void | |
1400 | do_nologin(struct passwd *pw) | |
1401 | { | |
1402 | FILE *f = NULL; | |
1403 | char buf[1024]; | |
1404 | ||
1405 | #ifdef HAVE_LOGIN_CAP | |
1406 | if (!login_getcapbool(lc, "ignorenologin", 0) && pw->pw_uid) | |
1407 | f = fopen(login_getcapstr(lc, "nologin", _PATH_NOLOGIN, | |
1408 | _PATH_NOLOGIN), "r"); | |
1409 | #else | |
1410 | if (pw->pw_uid) | |
1411 | f = fopen(_PATH_NOLOGIN, "r"); | |
1412 | #endif | |
1413 | if (f) { | |
1414 | /* /etc/nologin exists. Print its contents and exit. */ | |
70791e56 | 1415 | logit("User %.100s not allowed because %s exists", |
e54b3d7c | 1416 | pw->pw_name, _PATH_NOLOGIN); |
e9a17296 | 1417 | while (fgets(buf, sizeof(buf), f)) |
1418 | fputs(buf, stderr); | |
1419 | fclose(f); | |
1c14df9e | 1420 | fflush(NULL); |
e9a17296 | 1421 | exit(254); |
1422 | } | |
1423 | } | |
1424 | ||
1425 | /* Set login name, uid, gid, and groups. */ | |
2980ea68 | 1426 | void |
e9a17296 | 1427 | do_setusercontext(struct passwd *pw) |
1428 | { | |
1c14df9e | 1429 | #ifndef HAVE_CYGWIN |
1430 | if (getuid() == 0 || geteuid() == 0) | |
e9a17296 | 1431 | #endif /* HAVE_CYGWIN */ |
1c14df9e | 1432 | { |
1433 | ||
ff2d7a98 | 1434 | #ifdef HAVE_SETPCRED |
70791e56 | 1435 | if (setpcred(pw->pw_name, (char **)NULL) == -1) |
1436 | fatal("Failed to set process credentials"); | |
ff2d7a98 | 1437 | #endif /* HAVE_SETPCRED */ |
e9a17296 | 1438 | #ifdef HAVE_LOGIN_CAP |
e54b3d7c | 1439 | # ifdef __bsdi__ |
ff2d7a98 | 1440 | setpgid(0, 0); |
e54b3d7c | 1441 | # endif |
34fee935 | 1442 | #ifdef GSSAPI |
1443 | if (options.gss_authentication) { | |
1444 | temporarily_use_uid(pw); | |
1445 | ssh_gssapi_storecreds(); | |
1446 | restore_uid(); | |
1447 | } | |
1448 | #endif | |
416fd2a8 | 1449 | # ifdef USE_PAM |
1450 | if (options.use_pam) { | |
1451 | do_pam_session(); | |
1452 | do_pam_setcred(0); | |
1453 | } | |
1454 | # endif /* USE_PAM */ | |
e9a17296 | 1455 | if (setusercontext(lc, pw, pw->pw_uid, |
1456 | (LOGIN_SETALL & ~LOGIN_SETPATH)) < 0) { | |
1457 | perror("unable to set user context"); | |
1458 | exit(1); | |
1459 | } | |
1460 | #else | |
1461 | # if defined(HAVE_GETLUID) && defined(HAVE_SETLUID) | |
1462 | /* Sets login uid for accounting */ | |
1463 | if (getluid() == -1 && setluid(pw->pw_uid) == -1) | |
1464 | error("setluid: %s", strerror(errno)); | |
1465 | # endif /* defined(HAVE_GETLUID) && defined(HAVE_SETLUID) */ | |
1466 | ||
1467 | if (setlogin(pw->pw_name) < 0) | |
1468 | error("setlogin failed: %s", strerror(errno)); | |
1469 | if (setgid(pw->pw_gid) < 0) { | |
1470 | perror("setgid"); | |
1471 | exit(1); | |
1472 | } | |
1473 | /* Initialize the group list. */ | |
1474 | if (initgroups(pw->pw_name, pw->pw_gid) < 0) { | |
1475 | perror("initgroups"); | |
1476 | exit(1); | |
1477 | } | |
1478 | endgrent(); | |
34fee935 | 1479 | #ifdef GSSAPI |
1480 | if (options.gss_authentication) { | |
1481 | temporarily_use_uid(pw); | |
1482 | ssh_gssapi_storecreds(); | |
1483 | restore_uid(); | |
1484 | } | |
1485 | #endif | |
e9a17296 | 1486 | # ifdef USE_PAM |
1487 | /* | |
416fd2a8 | 1488 | * PAM credentials may take the form of supplementary groups. |
e9a17296 | 1489 | * These will have been wiped by the above initgroups() call. |
1490 | * Reestablish them here. | |
1491 | */ | |
70791e56 | 1492 | if (options.use_pam) { |
1493 | do_pam_session(); | |
1494 | do_pam_setcred(0); | |
1495 | } | |
e9a17296 | 1496 | # endif /* USE_PAM */ |
1497 | # if defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) | |
1498 | irix_setusercontext(pw); | |
1499 | # endif /* defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) */ | |
ff2d7a98 | 1500 | # ifdef _AIX |
e54b3d7c | 1501 | aix_usrinfo(pw); |
ff2d7a98 | 1502 | # endif /* _AIX */ |
34fee935 | 1503 | #if defined(HAVE_LIBIAF) && !defined(BROKEN_LIBIAF) |
1504 | if (set_id(pw->pw_name) != 0) { | |
1505 | exit(1); | |
1506 | } | |
1507 | #endif /* HAVE_LIBIAF && !BROKEN_LIBIAF */ | |
e9a17296 | 1508 | /* Permanently switch to the desired uid. */ |
1509 | permanently_set_uid(pw); | |
1510 | #endif | |
1511 | } | |
1c14df9e | 1512 | |
1513 | #ifdef HAVE_CYGWIN | |
1514 | if (is_winnt) | |
1515 | #endif | |
e9a17296 | 1516 | if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid) |
1517 | fatal("Failed to set uids to %u.", (u_int) pw->pw_uid); | |
1518 | } | |
1519 | ||
416fd2a8 | 1520 | static void |
1521 | do_pwchange(Session *s) | |
1522 | { | |
1b56ff3d | 1523 | fflush(NULL); |
416fd2a8 | 1524 | fprintf(stderr, "WARNING: Your password has expired.\n"); |
1525 | if (s->ttyfd != -1) { | |
1b56ff3d | 1526 | fprintf(stderr, |
416fd2a8 | 1527 | "You must change your password now and login again!\n"); |
34fee935 | 1528 | #ifdef PASSWD_NEEDS_USERNAME |
1529 | execl(_PATH_PASSWD_PROG, "passwd", s->pw->pw_name, | |
1530 | (char *)NULL); | |
1531 | #else | |
416fd2a8 | 1532 | execl(_PATH_PASSWD_PROG, "passwd", (char *)NULL); |
34fee935 | 1533 | #endif |
416fd2a8 | 1534 | perror("passwd"); |
1535 | } else { | |
1536 | fprintf(stderr, | |
1537 | "Password change required but no TTY available.\n"); | |
1538 | } | |
1539 | exit(1); | |
1540 | } | |
1541 | ||
2980ea68 | 1542 | static void |
1543 | launch_login(struct passwd *pw, const char *hostname) | |
1544 | { | |
1545 | /* Launch login(1). */ | |
1546 | ||
ff2d7a98 | 1547 | execl(LOGIN_PROGRAM, "login", "-h", hostname, |
2980ea68 | 1548 | #ifdef xxxLOGIN_NEEDS_TERM |
ff2d7a98 | 1549 | (s->term ? s->term : "unknown"), |
2980ea68 | 1550 | #endif /* LOGIN_NEEDS_TERM */ |
1551 | #ifdef LOGIN_NO_ENDOPT | |
1552 | "-p", "-f", pw->pw_name, (char *)NULL); | |
1553 | #else | |
1554 | "-p", "-f", "--", pw->pw_name, (char *)NULL); | |
1555 | #endif | |
1556 | ||
1557 | /* Login couldn't be executed, die. */ | |
1558 | ||
1559 | perror("login"); | |
1560 | exit(1); | |
1561 | } | |
1562 | ||
416fd2a8 | 1563 | static void |
1564 | child_close_fds(void) | |
1565 | { | |
1566 | int i; | |
1567 | ||
1568 | if (packet_get_connection_in() == packet_get_connection_out()) | |
1569 | close(packet_get_connection_in()); | |
1570 | else { | |
1571 | close(packet_get_connection_in()); | |
1572 | close(packet_get_connection_out()); | |
1573 | } | |
1574 | /* | |
1575 | * Close all descriptors related to channels. They will still remain | |
1576 | * open in the parent. | |
1577 | */ | |
1578 | /* XXX better use close-on-exec? -markus */ | |
1579 | channel_close_all(); | |
1580 | ||
1581 | /* | |
1582 | * Close any extra file descriptors. Note that there may still be | |
1583 | * descriptors left by system functions. They will be closed later. | |
1584 | */ | |
1585 | endpwent(); | |
1586 | ||
1587 | /* | |
e00da40d | 1588 | * Close any extra open file descriptors so that we don't have them |
416fd2a8 | 1589 | * hanging around in clients. Note that we want to do this after |
1590 | * initgroups, because at least on Solaris 2.3 it leaves file | |
1591 | * descriptors open. | |
1592 | */ | |
1593 | for (i = 3; i < 64; i++) | |
1594 | close(i); | |
1595 | } | |
1596 | ||
e9a17296 | 1597 | /* |
1598 | * Performs common processing for the child, such as setting up the | |
1599 | * environment, closing extra file descriptors, setting the user and group | |
1600 | * ids, and executing the command or shell. | |
1601 | */ | |
1602 | void | |
1603 | do_child(Session *s, const char *command) | |
1604 | { | |
1605 | extern char **environ; | |
1606 | char **env; | |
1607 | char *argv[10]; | |
1608 | const char *shell, *shell0, *hostname = NULL; | |
1609 | struct passwd *pw = s->pw; | |
e9a17296 | 1610 | |
f2fd21a2 | 1611 | #ifdef AFS_KRB5 |
1612 | /* Default place to look for aklog. */ | |
1613 | #ifdef AKLOG_PATH | |
1614 | #define KPROGDIR AKLOG_PATH | |
1615 | #else | |
1616 | #define KPROGDIR "/usr/bin/aklog" | |
1617 | #endif /* AKLOG_PATH */ | |
1618 | ||
1619 | struct stat st; | |
1620 | char *aklog_path; | |
1621 | #endif /* AFS_KRB5 */ | |
1622 | ||
e9a17296 | 1623 | /* remove hostkey from the child's memory */ |
1624 | destroy_sensitive_data(); | |
1625 | ||
416fd2a8 | 1626 | /* Force a password change */ |
1627 | if (s->authctxt->force_pwchange) { | |
1628 | do_setusercontext(pw); | |
1629 | child_close_fds(); | |
1630 | do_pwchange(s); | |
1631 | exit(1); | |
1632 | } | |
1633 | ||
e9a17296 | 1634 | /* login(1) is only called if we execute the login shell */ |
1635 | if (options.use_login && command != NULL) | |
1636 | options.use_login = 0; | |
1637 | ||
e54b3d7c | 1638 | #ifdef _UNICOS |
1639 | cray_setup(pw->pw_uid, pw->pw_name, command); | |
1640 | #endif /* _UNICOS */ | |
1641 | ||
e9a17296 | 1642 | /* |
1643 | * Login(1) does this as well, and it needs uid 0 for the "-h" | |
1644 | * switch, so we let login(1) to this for us. | |
1645 | */ | |
1646 | if (!options.use_login) { | |
1647 | #ifdef HAVE_OSF_SIA | |
1c14df9e | 1648 | session_setup_sia(pw, s->ttyfd == -1 ? NULL : s->tty); |
e9a17296 | 1649 | if (!check_quietlogin(s, command)) |
1650 | do_motd(); | |
1651 | #else /* HAVE_OSF_SIA */ | |
e00da40d | 1652 | /* When PAM is enabled we rely on it to do the nologin check */ |
1653 | if (!options.use_pam) | |
1654 | do_nologin(pw); | |
e9a17296 | 1655 | do_setusercontext(pw); |
1b56ff3d | 1656 | /* |
1657 | * PAM session modules in do_setusercontext may have | |
1658 | * generated messages, so if this in an interactive | |
1659 | * login then display them too. | |
1660 | */ | |
34fee935 | 1661 | if (!check_quietlogin(s, command)) |
1b56ff3d | 1662 | display_loginmsg(); |
e9a17296 | 1663 | #endif /* HAVE_OSF_SIA */ |
1664 | } | |
1665 | ||
34fee935 | 1666 | #ifdef USE_PAM |
1667 | if (options.use_pam && !options.use_login && !is_pam_session_open()) { | |
1668 | debug3("PAM session not opened, exiting"); | |
1669 | display_loginmsg(); | |
1670 | exit(254); | |
1671 | } | |
1672 | #endif | |
1673 | ||
e9a17296 | 1674 | /* |
1675 | * Get the shell from the password data. An empty shell field is | |
1676 | * legal, and means /bin/sh. | |
1677 | */ | |
1678 | shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell; | |
1c14df9e | 1679 | |
1680 | /* | |
1681 | * Make sure $SHELL points to the shell from the password file, | |
1682 | * even if shell is overridden from login.conf | |
1683 | */ | |
1684 | env = do_setup_env(s, shell); | |
1685 | ||
e9a17296 | 1686 | #ifdef HAVE_LOGIN_CAP |
1687 | shell = login_getcapstr(lc, "shell", (char *)shell, (char *)shell); | |
1688 | #endif | |
1689 | ||
3c0ef626 | 1690 | /* we have to stash the hostname before we close our socket. */ |
1691 | if (options.use_login) | |
1692 | hostname = get_remote_name_or_ip(utmp_len, | |
70791e56 | 1693 | options.use_dns); |
3c0ef626 | 1694 | /* |
1695 | * Close the connection descriptors; note that this is the child, and | |
1696 | * the server will still have the socket open, and it is important | |
1697 | * that we do not shutdown it. Note that the descriptors cannot be | |
1698 | * closed before building the environment, as we call | |
1699 | * get_remote_ipaddr there. | |
1700 | */ | |
416fd2a8 | 1701 | child_close_fds(); |
3c0ef626 | 1702 | |
1703 | /* | |
416fd2a8 | 1704 | * Must take new environment into use so that .ssh/rc, |
1705 | * /etc/ssh/sshrc and xauth are run in the proper environment. | |
3c0ef626 | 1706 | */ |
416fd2a8 | 1707 | environ = env; |
3c0ef626 | 1708 | |
416fd2a8 | 1709 | #if defined(KRB5) && defined(USE_AFS) |
3c0ef626 | 1710 | /* |
416fd2a8 | 1711 | * At this point, we check to see if AFS is active and if we have |
1712 | * a valid Kerberos 5 TGT. If so, it seems like a good idea to see | |
1713 | * if we can (and need to) extend the ticket into an AFS token. If | |
1714 | * we don't do this, we run into potential problems if the user's | |
1715 | * home directory is in AFS and it's not world-readable. | |
3c0ef626 | 1716 | */ |
3c0ef626 | 1717 | |
416fd2a8 | 1718 | if (options.kerberos_get_afs_token && k_hasafs() && |
34fee935 | 1719 | (s->authctxt->krb5_ctx != NULL)) { |
416fd2a8 | 1720 | char cell[64]; |
1721 | ||
1722 | debug("Getting AFS token"); | |
1723 | ||
1724 | k_setpag(); | |
1725 | ||
1726 | if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0) | |
1727 | krb5_afslog(s->authctxt->krb5_ctx, | |
1728 | s->authctxt->krb5_fwd_ccache, cell, NULL); | |
1729 | ||
1730 | krb5_afslog_home(s->authctxt->krb5_ctx, | |
1731 | s->authctxt->krb5_fwd_ccache, NULL, NULL, pw->pw_dir); | |
1732 | } | |
1733 | #endif | |
3c0ef626 | 1734 | |
f2fd21a2 | 1735 | #ifdef AFS_KRB5 |
1736 | ||
1737 | /* User has authenticated, and if a ticket was going to be | |
1738 | * passed we would have it. KRB5CCNAME should already be set. | |
1739 | * Now try to get an AFS token using aklog. | |
1740 | */ | |
1741 | if (k_hasafs()) { /* Do we have AFS? */ | |
1742 | ||
1743 | aklog_path = xstrdup(KPROGDIR); | |
1744 | ||
1745 | /* | |
1746 | * Make sure it exists before we try to run it | |
1747 | */ | |
1748 | if (stat(aklog_path, &st) == 0) { | |
1749 | debug("Running %s to get afs token.",aklog_path); | |
1750 | system(aklog_path); | |
1751 | } else { | |
1752 | debug("%s does not exist.",aklog_path); | |
1753 | } | |
1754 | ||
1755 | xfree(aklog_path); | |
1756 | } | |
1757 | #endif /* AFS_KRB5 */ | |
1758 | ||
88928908 | 1759 | #ifdef SESSION_HOOKS |
1760 | if (options.session_hooks_allow && | |
1761 | options.session_hooks_startup_cmd) | |
1762 | { | |
1763 | execute_session_hook(options.session_hooks_startup_cmd, | |
1764 | s->authctxt, | |
1765 | /* startup = */ 1, | |
1766 | options.session_hooks_shutdown_cmd != NULL); | |
1767 | } | |
1768 | #endif | |
3c0ef626 | 1769 | |
e00da40d | 1770 | /* Change current directory to the user's home directory. */ |
3c0ef626 | 1771 | if (chdir(pw->pw_dir) < 0) { |
1772 | fprintf(stderr, "Could not chdir to home directory %s: %s\n", | |
1773 | pw->pw_dir, strerror(errno)); | |
1774 | #ifdef HAVE_LOGIN_CAP | |
1775 | if (login_getcapbool(lc, "requirehome", 0)) | |
1776 | exit(1); | |
1777 | #endif | |
1778 | } | |
1779 | ||
e9a17296 | 1780 | if (!options.use_login) |
1781 | do_rc_files(s, shell); | |
3c0ef626 | 1782 | |
1783 | /* restore SIGPIPE for child */ | |
1784 | signal(SIGPIPE, SIG_DFL); | |
1785 | ||
e9a17296 | 1786 | if (options.use_login) { |
2980ea68 | 1787 | launch_login(pw, hostname); |
1788 | /* NEVERREACHED */ | |
e9a17296 | 1789 | } |
1790 | ||
1791 | /* Get the last component of the shell name. */ | |
1792 | if ((shell0 = strrchr(shell, '/')) != NULL) | |
1793 | shell0++; | |
1794 | else | |
1795 | shell0 = shell; | |
1796 | ||
3c0ef626 | 1797 | /* |
1798 | * If we have no command, execute the shell. In this case, the shell | |
1799 | * name to be passed in argv[0] is preceded by '-' to indicate that | |
1800 | * this is a login shell. | |
1801 | */ | |
1802 | if (!command) { | |
e9a17296 | 1803 | char argv0[256]; |
3c0ef626 | 1804 | |
e9a17296 | 1805 | /* Start the shell. Set initial character to '-'. */ |
1806 | argv0[0] = '-'; | |
3c0ef626 | 1807 | |
e9a17296 | 1808 | if (strlcpy(argv0 + 1, shell0, sizeof(argv0) - 1) |
1809 | >= sizeof(argv0) - 1) { | |
1810 | errno = EINVAL; | |
3c0ef626 | 1811 | perror(shell); |
1812 | exit(1); | |
e9a17296 | 1813 | } |
3c0ef626 | 1814 | |
e9a17296 | 1815 | /* Execute the shell. */ |
1816 | argv[0] = argv0; | |
1817 | argv[1] = NULL; | |
574478c5 | 1818 | execve(shell, argv, environ); |
3c0ef626 | 1819 | |
e9a17296 | 1820 | /* Executing the shell failed. */ |
1821 | perror(shell); | |
1822 | exit(1); | |
3c0ef626 | 1823 | } |
1824 | /* | |
1825 | * Execute the command using the user's shell. This uses the -c | |
1826 | * option to execute the command. | |
1827 | */ | |
e9a17296 | 1828 | argv[0] = (char *) shell0; |
3c0ef626 | 1829 | argv[1] = "-c"; |
1830 | argv[2] = (char *) command; | |
1831 | argv[3] = NULL; | |
574478c5 | 1832 | execve(shell, argv, environ); |
3c0ef626 | 1833 | perror(shell); |
1834 | exit(1); | |
1835 | } | |
1836 | ||
1837 | Session * | |
1838 | session_new(void) | |
1839 | { | |
1840 | int i; | |
1841 | static int did_init = 0; | |
1842 | if (!did_init) { | |
1843 | debug("session_new: init"); | |
e9a17296 | 1844 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1845 | sessions[i].used = 0; |
1846 | } | |
1847 | did_init = 1; | |
1848 | } | |
e9a17296 | 1849 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1850 | Session *s = &sessions[i]; |
1851 | if (! s->used) { | |
1852 | memset(s, 0, sizeof(*s)); | |
1853 | s->chanid = -1; | |
1854 | s->ptyfd = -1; | |
1855 | s->ttyfd = -1; | |
1856 | s->used = 1; | |
1857 | s->self = i; | |
34fee935 | 1858 | s->x11_chanids = NULL; |
3c0ef626 | 1859 | debug("session_new: session %d", i); |
1860 | return s; | |
1861 | } | |
1862 | } | |
1863 | return NULL; | |
1864 | } | |
1865 | ||
1866 | static void | |
1867 | session_dump(void) | |
1868 | { | |
1869 | int i; | |
e9a17296 | 1870 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1871 | Session *s = &sessions[i]; |
ff2d7a98 | 1872 | debug("dump: used %d session %d %p channel %d pid %ld", |
3c0ef626 | 1873 | s->used, |
1874 | s->self, | |
1875 | s, | |
1876 | s->chanid, | |
ff2d7a98 | 1877 | (long)s->pid); |
3c0ef626 | 1878 | } |
1879 | } | |
1880 | ||
1881 | int | |
1882 | session_open(Authctxt *authctxt, int chanid) | |
1883 | { | |
1884 | Session *s = session_new(); | |
1885 | debug("session_open: channel %d", chanid); | |
1886 | if (s == NULL) { | |
1887 | error("no more sessions"); | |
1888 | return 0; | |
1889 | } | |
1890 | s->authctxt = authctxt; | |
1891 | s->pw = authctxt->pw; | |
416fd2a8 | 1892 | if (s->pw == NULL || !authctxt->valid) |
3c0ef626 | 1893 | fatal("no user for session %d", s->self); |
1894 | debug("session_open: session %d: link with channel %d", s->self, chanid); | |
1895 | s->chanid = chanid; | |
1896 | return 1; | |
1897 | } | |
1898 | ||
2980ea68 | 1899 | Session * |
1900 | session_by_tty(char *tty) | |
1901 | { | |
1902 | int i; | |
1903 | for (i = 0; i < MAX_SESSIONS; i++) { | |
1904 | Session *s = &sessions[i]; | |
1905 | if (s->used && s->ttyfd != -1 && strcmp(s->tty, tty) == 0) { | |
1906 | debug("session_by_tty: session %d tty %s", i, tty); | |
1907 | return s; | |
1908 | } | |
1909 | } | |
1910 | debug("session_by_tty: unknown tty %.100s", tty); | |
1911 | session_dump(); | |
1912 | return NULL; | |
1913 | } | |
1914 | ||
3c0ef626 | 1915 | static Session * |
1916 | session_by_channel(int id) | |
1917 | { | |
1918 | int i; | |
e9a17296 | 1919 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1920 | Session *s = &sessions[i]; |
1921 | if (s->used && s->chanid == id) { | |
1922 | debug("session_by_channel: session %d channel %d", i, id); | |
1923 | return s; | |
1924 | } | |
1925 | } | |
1926 | debug("session_by_channel: unknown channel %d", id); | |
1927 | session_dump(); | |
1928 | return NULL; | |
1929 | } | |
1930 | ||
34fee935 | 1931 | static Session * |
1932 | session_by_x11_channel(int id) | |
1933 | { | |
1934 | int i, j; | |
1935 | ||
1936 | for (i = 0; i < MAX_SESSIONS; i++) { | |
1937 | Session *s = &sessions[i]; | |
1938 | ||
1939 | if (s->x11_chanids == NULL || !s->used) | |
1940 | continue; | |
1941 | for (j = 0; s->x11_chanids[j] != -1; j++) { | |
1942 | if (s->x11_chanids[j] == id) { | |
1943 | debug("session_by_x11_channel: session %d " | |
1944 | "channel %d", s->self, id); | |
1945 | return s; | |
1946 | } | |
1947 | } | |
1948 | } | |
1949 | debug("session_by_x11_channel: unknown channel %d", id); | |
1950 | session_dump(); | |
1951 | return NULL; | |
1952 | } | |
1953 | ||
3c0ef626 | 1954 | static Session * |
1955 | session_by_pid(pid_t pid) | |
1956 | { | |
1957 | int i; | |
ff2d7a98 | 1958 | debug("session_by_pid: pid %ld", (long)pid); |
e9a17296 | 1959 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 1960 | Session *s = &sessions[i]; |
1961 | if (s->used && s->pid == pid) | |
1962 | return s; | |
1963 | } | |
ff2d7a98 | 1964 | error("session_by_pid: unknown pid %ld", (long)pid); |
3c0ef626 | 1965 | session_dump(); |
1966 | return NULL; | |
1967 | } | |
1968 | ||
1969 | static int | |
1970 | session_window_change_req(Session *s) | |
1971 | { | |
1972 | s->col = packet_get_int(); | |
1973 | s->row = packet_get_int(); | |
1974 | s->xpixel = packet_get_int(); | |
1975 | s->ypixel = packet_get_int(); | |
e9a17296 | 1976 | packet_check_eom(); |
3c0ef626 | 1977 | pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel); |
1978 | return 1; | |
1979 | } | |
1980 | ||
1981 | static int | |
1982 | session_pty_req(Session *s) | |
1983 | { | |
1984 | u_int len; | |
1985 | int n_bytes; | |
1986 | ||
1987 | if (no_pty_flag) { | |
1988 | debug("Allocating a pty not permitted for this authentication."); | |
1989 | return 0; | |
1990 | } | |
1991 | if (s->ttyfd != -1) { | |
1992 | packet_disconnect("Protocol error: you already have a pty."); | |
1993 | return 0; | |
1994 | } | |
1995 | ||
1996 | s->term = packet_get_string(&len); | |
1997 | ||
1998 | if (compat20) { | |
1999 | s->col = packet_get_int(); | |
2000 | s->row = packet_get_int(); | |
2001 | } else { | |
2002 | s->row = packet_get_int(); | |
2003 | s->col = packet_get_int(); | |
2004 | } | |
2005 | s->xpixel = packet_get_int(); | |
2006 | s->ypixel = packet_get_int(); | |
2007 | ||
2008 | if (strcmp(s->term, "") == 0) { | |
2009 | xfree(s->term); | |
2010 | s->term = NULL; | |
2011 | } | |
2012 | ||
2013 | /* Allocate a pty and open it. */ | |
2014 | debug("Allocating pty."); | |
2980ea68 | 2015 | if (!PRIVSEP(pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty)))) { |
3c0ef626 | 2016 | if (s->term) |
2017 | xfree(s->term); | |
2018 | s->term = NULL; | |
2019 | s->ptyfd = -1; | |
2020 | s->ttyfd = -1; | |
2021 | error("session_pty_req: session %d alloc failed", s->self); | |
2022 | return 0; | |
2023 | } | |
2024 | debug("session_pty_req: session %d alloc %s", s->self, s->tty); | |
2025 | ||
2026 | /* for SSH1 the tty modes length is not given */ | |
2027 | if (!compat20) | |
2028 | n_bytes = packet_remaining(); | |
2029 | tty_parse_modes(s->ttyfd, &n_bytes); | |
2030 | ||
2980ea68 | 2031 | if (!use_privsep) |
2032 | pty_setowner(s->pw, s->tty); | |
3c0ef626 | 2033 | |
2034 | /* Set window size from the packet. */ | |
2035 | pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel); | |
2036 | ||
e9a17296 | 2037 | packet_check_eom(); |
3c0ef626 | 2038 | session_proctitle(s); |
2039 | return 1; | |
2040 | } | |
2041 | ||
2042 | static int | |
2043 | session_subsystem_req(Session *s) | |
2044 | { | |
2045 | struct stat st; | |
2046 | u_int len; | |
2047 | int success = 0; | |
2048 | char *cmd, *subsys = packet_get_string(&len); | |
34fee935 | 2049 | u_int i; |
3c0ef626 | 2050 | |
e9a17296 | 2051 | packet_check_eom(); |
70791e56 | 2052 | logit("subsystem request for %.100s", subsys); |
3c0ef626 | 2053 | |
2054 | for (i = 0; i < options.num_subsystems; i++) { | |
2055 | if (strcmp(subsys, options.subsystem_name[i]) == 0) { | |
2056 | cmd = options.subsystem_command[i]; | |
2057 | if (stat(cmd, &st) < 0) { | |
2058 | error("subsystem: cannot stat %s: %s", cmd, | |
2059 | strerror(errno)); | |
2060 | break; | |
2061 | } | |
2062 | debug("subsystem: exec() %s", cmd); | |
2063 | s->is_subsystem = 1; | |
2064 | do_exec(s, cmd); | |
2065 | success = 1; | |
e9a17296 | 2066 | break; |
3c0ef626 | 2067 | } |
2068 | } | |
2069 | ||
2070 | if (!success) | |
70791e56 | 2071 | logit("subsystem request for %.100s failed, subsystem not found", |
3c0ef626 | 2072 | subsys); |
2073 | ||
2074 | xfree(subsys); | |
2075 | return success; | |
2076 | } | |
2077 | ||
2078 | static int | |
2079 | session_x11_req(Session *s) | |
2080 | { | |
2081 | int success; | |
2082 | ||
34fee935 | 2083 | if (s->auth_proto != NULL || s->auth_data != NULL) { |
2084 | error("session_x11_req: session %d: " | |
e00da40d | 2085 | "x11 forwarding already active", s->self); |
34fee935 | 2086 | return 0; |
2087 | } | |
3c0ef626 | 2088 | s->single_connection = packet_get_char(); |
2089 | s->auth_proto = packet_get_string(NULL); | |
2090 | s->auth_data = packet_get_string(NULL); | |
2091 | s->screen = packet_get_int(); | |
e9a17296 | 2092 | packet_check_eom(); |
3c0ef626 | 2093 | |
2094 | success = session_setup_x11fwd(s); | |
2095 | if (!success) { | |
2096 | xfree(s->auth_proto); | |
2097 | xfree(s->auth_data); | |
2098 | s->auth_proto = NULL; | |
2099 | s->auth_data = NULL; | |
2100 | } | |
2101 | return success; | |
2102 | } | |
2103 | ||
2104 | static int | |
2105 | session_shell_req(Session *s) | |
2106 | { | |
e9a17296 | 2107 | packet_check_eom(); |
3c0ef626 | 2108 | do_exec(s, NULL); |
2109 | return 1; | |
2110 | } | |
2111 | ||
2112 | static int | |
2113 | session_exec_req(Session *s) | |
2114 | { | |
2115 | u_int len; | |
2116 | char *command = packet_get_string(&len); | |
e9a17296 | 2117 | packet_check_eom(); |
3c0ef626 | 2118 | do_exec(s, command); |
2119 | xfree(command); | |
2120 | return 1; | |
2121 | } | |
2122 | ||
70791e56 | 2123 | static int |
2124 | session_break_req(Session *s) | |
2125 | { | |
70791e56 | 2126 | |
1b56ff3d | 2127 | packet_get_int(); /* ignored */ |
70791e56 | 2128 | packet_check_eom(); |
2129 | ||
2130 | if (s->ttyfd == -1 || | |
2131 | tcsendbreak(s->ttyfd, 0) < 0) | |
2132 | return 0; | |
2133 | return 1; | |
2134 | } | |
2135 | ||
1b56ff3d | 2136 | static int |
2137 | session_env_req(Session *s) | |
2138 | { | |
2139 | char *name, *val; | |
2140 | u_int name_len, val_len, i; | |
2141 | ||
2142 | name = packet_get_string(&name_len); | |
2143 | val = packet_get_string(&val_len); | |
2144 | packet_check_eom(); | |
2145 | ||
2146 | /* Don't set too many environment variables */ | |
2147 | if (s->num_env > 128) { | |
2148 | debug2("Ignoring env request %s: too many env vars", name); | |
2149 | goto fail; | |
2150 | } | |
2151 | ||
2152 | for (i = 0; i < options.num_accept_env; i++) { | |
2153 | if (match_pattern(name, options.accept_env[i])) { | |
2154 | debug2("Setting env %d: %s=%s", s->num_env, name, val); | |
2155 | s->env = xrealloc(s->env, sizeof(*s->env) * | |
2156 | (s->num_env + 1)); | |
2157 | s->env[s->num_env].name = name; | |
2158 | s->env[s->num_env].val = val; | |
2159 | s->num_env++; | |
2160 | return (1); | |
2161 | } | |
2162 | } | |
2163 | debug2("Ignoring env request %s: disallowed name", name); | |
2164 | ||
2165 | fail: | |
2166 | xfree(name); | |
2167 | xfree(val); | |
2168 | return (0); | |
2169 | } | |
2170 | ||
3c0ef626 | 2171 | static int |
2172 | session_auth_agent_req(Session *s) | |
2173 | { | |
2174 | static int called = 0; | |
e9a17296 | 2175 | packet_check_eom(); |
3c0ef626 | 2176 | if (no_agent_forwarding_flag) { |
2177 | debug("session_auth_agent_req: no_agent_forwarding_flag"); | |
2178 | return 0; | |
2179 | } | |
2180 | if (called) { | |
2181 | return 0; | |
2182 | } else { | |
2183 | called = 1; | |
2184 | return auth_input_request_forwarding(s->pw); | |
2185 | } | |
2186 | } | |
2187 | ||
e9a17296 | 2188 | int |
2189 | session_input_channel_req(Channel *c, const char *rtype) | |
3c0ef626 | 2190 | { |
3c0ef626 | 2191 | int success = 0; |
3c0ef626 | 2192 | Session *s; |
3c0ef626 | 2193 | |
e9a17296 | 2194 | if ((s = session_by_channel(c->self)) == NULL) { |
70791e56 | 2195 | logit("session_input_channel_req: no session %d req %.100s", |
e9a17296 | 2196 | c->self, rtype); |
2197 | return 0; | |
2198 | } | |
2199 | debug("session_input_channel_req: session %d req %s", s->self, rtype); | |
3c0ef626 | 2200 | |
2201 | /* | |
2202 | * a session is in LARVAL state until a shell, a command | |
2203 | * or a subsystem is executed | |
2204 | */ | |
2205 | if (c->type == SSH_CHANNEL_LARVAL) { | |
2206 | if (strcmp(rtype, "shell") == 0) { | |
2207 | success = session_shell_req(s); | |
2208 | } else if (strcmp(rtype, "exec") == 0) { | |
2209 | success = session_exec_req(s); | |
2210 | } else if (strcmp(rtype, "pty-req") == 0) { | |
2211 | success = session_pty_req(s); | |
2212 | } else if (strcmp(rtype, "x11-req") == 0) { | |
2213 | success = session_x11_req(s); | |
2214 | } else if (strcmp(rtype, "auth-agent-req@openssh.com") == 0) { | |
2215 | success = session_auth_agent_req(s); | |
2216 | } else if (strcmp(rtype, "subsystem") == 0) { | |
2217 | success = session_subsystem_req(s); | |
1b56ff3d | 2218 | } else if (strcmp(rtype, "env") == 0) { |
2219 | success = session_env_req(s); | |
3c0ef626 | 2220 | } |
2221 | } | |
2222 | if (strcmp(rtype, "window-change") == 0) { | |
2223 | success = session_window_change_req(s); | |
1b56ff3d | 2224 | } else if (strcmp(rtype, "break") == 0) { |
2225 | success = session_break_req(s); | |
3c0ef626 | 2226 | } |
1b56ff3d | 2227 | |
e9a17296 | 2228 | return success; |
3c0ef626 | 2229 | } |
2230 | ||
2231 | void | |
2232 | session_set_fds(Session *s, int fdin, int fdout, int fderr) | |
2233 | { | |
2234 | if (!compat20) | |
2235 | fatal("session_set_fds: called for proto != 2.0"); | |
2236 | /* | |
2237 | * now that have a child and a pipe to the child, | |
2238 | * we can activate our channel and register the fd's | |
2239 | */ | |
2240 | if (s->chanid == -1) | |
2241 | fatal("no channel for session %d", s->self); | |
e00da40d | 2242 | if(options.hpn_disabled) |
2243 | channel_set_fds(s->chanid, | |
2244 | fdout, fdin, fderr, | |
2245 | fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ, | |
2246 | 1, | |
2247 | CHAN_SES_WINDOW_DEFAULT); | |
2248 | else | |
2249 | channel_set_fds(s->chanid, | |
2250 | fdout, fdin, fderr, | |
2251 | fderr == -1 ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ, | |
2252 | 1, | |
2253 | options.hpn_buffer_size); | |
3c0ef626 | 2254 | } |
2255 | ||
2256 | /* | |
2257 | * Function to perform pty cleanup. Also called if we get aborted abnormally | |
2258 | * (e.g., due to a dropped connection). | |
2259 | */ | |
2980ea68 | 2260 | void |
416fd2a8 | 2261 | session_pty_cleanup2(Session *s) |
3c0ef626 | 2262 | { |
3c0ef626 | 2263 | if (s == NULL) { |
2264 | error("session_pty_cleanup: no session"); | |
2265 | return; | |
2266 | } | |
2267 | if (s->ttyfd == -1) | |
2268 | return; | |
2269 | ||
2270 | debug("session_pty_cleanup: session %d release %s", s->self, s->tty); | |
2271 | ||
2272 | /* Record that the user has logged out. */ | |
2273 | if (s->pid != 0) | |
e9a17296 | 2274 | record_logout(s->pid, s->tty, s->pw->pw_name); |
3c0ef626 | 2275 | |
2276 | /* Release the pseudo-tty. */ | |
2980ea68 | 2277 | if (getuid() == 0) |
2278 | pty_release(s->tty); | |
3c0ef626 | 2279 | |
2280 | /* | |
2281 | * Close the server side of the socket pairs. We must do this after | |
2282 | * the pty cleanup, so that another process doesn't get this pty | |
2283 | * while we're still cleaning up. | |
2284 | */ | |
2285 | if (close(s->ptymaster) < 0) | |
2980ea68 | 2286 | error("close(s->ptymaster/%d): %s", s->ptymaster, strerror(errno)); |
3c0ef626 | 2287 | |
2288 | /* unlink pty from session */ | |
2289 | s->ttyfd = -1; | |
2290 | } | |
2291 | ||
2980ea68 | 2292 | void |
416fd2a8 | 2293 | session_pty_cleanup(Session *s) |
2980ea68 | 2294 | { |
416fd2a8 | 2295 | PRIVSEP(session_pty_cleanup2(s)); |
2980ea68 | 2296 | } |
2297 | ||
e54b3d7c | 2298 | static char * |
2299 | sig2name(int sig) | |
2300 | { | |
2301 | #define SSH_SIG(x) if (sig == SIG ## x) return #x | |
2302 | SSH_SIG(ABRT); | |
2303 | SSH_SIG(ALRM); | |
2304 | SSH_SIG(FPE); | |
2305 | SSH_SIG(HUP); | |
2306 | SSH_SIG(ILL); | |
2307 | SSH_SIG(INT); | |
2308 | SSH_SIG(KILL); | |
2309 | SSH_SIG(PIPE); | |
2310 | SSH_SIG(QUIT); | |
2311 | SSH_SIG(SEGV); | |
2312 | SSH_SIG(TERM); | |
2313 | SSH_SIG(USR1); | |
2314 | SSH_SIG(USR2); | |
2315 | #undef SSH_SIG | |
2316 | return "SIG@openssh.com"; | |
2317 | } | |
2318 | ||
34fee935 | 2319 | static void |
2320 | session_close_x11(int id) | |
2321 | { | |
2322 | Channel *c; | |
2323 | ||
e00da40d | 2324 | if ((c = channel_by_id(id)) == NULL) { |
34fee935 | 2325 | debug("session_close_x11: x11 channel %d missing", id); |
2326 | } else { | |
2327 | /* Detach X11 listener */ | |
2328 | debug("session_close_x11: detach x11 channel %d", id); | |
2329 | channel_cancel_cleanup(id); | |
2330 | if (c->ostate != CHAN_OUTPUT_CLOSED) | |
2331 | chan_mark_dead(c); | |
2332 | } | |
2333 | } | |
2334 | ||
2335 | static void | |
2336 | session_close_single_x11(int id, void *arg) | |
2337 | { | |
2338 | Session *s; | |
2339 | u_int i; | |
2340 | ||
2341 | debug3("session_close_single_x11: channel %d", id); | |
2342 | channel_cancel_cleanup(id); | |
2343 | if ((s = session_by_x11_channel(id)) == NULL) | |
2344 | fatal("session_close_single_x11: no x11 channel %d", id); | |
2345 | for (i = 0; s->x11_chanids[i] != -1; i++) { | |
2346 | debug("session_close_single_x11: session %d: " | |
2347 | "closing channel %d", s->self, s->x11_chanids[i]); | |
2348 | /* | |
2349 | * The channel "id" is already closing, but make sure we | |
2350 | * close all of its siblings. | |
2351 | */ | |
2352 | if (s->x11_chanids[i] != id) | |
2353 | session_close_x11(s->x11_chanids[i]); | |
2354 | } | |
2355 | xfree(s->x11_chanids); | |
2356 | s->x11_chanids = NULL; | |
2357 | if (s->display) { | |
2358 | xfree(s->display); | |
2359 | s->display = NULL; | |
2360 | } | |
2361 | if (s->auth_proto) { | |
2362 | xfree(s->auth_proto); | |
2363 | s->auth_proto = NULL; | |
2364 | } | |
2365 | if (s->auth_data) { | |
2366 | xfree(s->auth_data); | |
2367 | s->auth_data = NULL; | |
2368 | } | |
2369 | if (s->auth_display) { | |
2370 | xfree(s->auth_display); | |
2371 | s->auth_display = NULL; | |
2372 | } | |
2373 | } | |
2374 | ||
3c0ef626 | 2375 | static void |
2376 | session_exit_message(Session *s, int status) | |
2377 | { | |
2378 | Channel *c; | |
e9a17296 | 2379 | |
2380 | if ((c = channel_lookup(s->chanid)) == NULL) | |
3c0ef626 | 2381 | fatal("session_exit_message: session %d: no channel %d", |
2382 | s->self, s->chanid); | |
ff2d7a98 | 2383 | debug("session_exit_message: session %d channel %d pid %ld", |
2384 | s->self, s->chanid, (long)s->pid); | |
3c0ef626 | 2385 | |
2386 | if (WIFEXITED(status)) { | |
e9a17296 | 2387 | channel_request_start(s->chanid, "exit-status", 0); |
3c0ef626 | 2388 | packet_put_int(WEXITSTATUS(status)); |
2389 | packet_send(); | |
2390 | } else if (WIFSIGNALED(status)) { | |
e9a17296 | 2391 | channel_request_start(s->chanid, "exit-signal", 0); |
e54b3d7c | 2392 | packet_put_cstring(sig2name(WTERMSIG(status))); |
3c0ef626 | 2393 | #ifdef WCOREDUMP |
2394 | packet_put_char(WCOREDUMP(status)); | |
2395 | #else /* WCOREDUMP */ | |
2396 | packet_put_char(0); | |
2397 | #endif /* WCOREDUMP */ | |
2398 | packet_put_cstring(""); | |
2399 | packet_put_cstring(""); | |
2400 | packet_send(); | |
2401 | } else { | |
2402 | /* Some weird exit cause. Just exit. */ | |
2403 | packet_disconnect("wait returned status %04x.", status); | |
2404 | } | |
2405 | ||
2406 | /* disconnect channel */ | |
2407 | debug("session_exit_message: release channel %d", s->chanid); | |
e00da40d | 2408 | |
2409 | /* | |
2410 | * Adjust cleanup callback attachment to send close messages when | |
2411 | * the channel gets EOF. The session will be then be closed | |
2412 | * by session_close_by_channel when the childs close their fds. | |
2413 | */ | |
2414 | channel_register_cleanup(c->self, session_close_by_channel, 1); | |
2415 | ||
3c0ef626 | 2416 | /* |
2417 | * emulate a write failure with 'chan_write_failed', nobody will be | |
2418 | * interested in data we write. | |
2419 | * Note that we must not call 'chan_read_failed', since there could | |
2420 | * be some more data waiting in the pipe. | |
2421 | */ | |
2422 | if (c->ostate != CHAN_OUTPUT_CLOSED) | |
2423 | chan_write_failed(c); | |
3c0ef626 | 2424 | } |
2425 | ||
2980ea68 | 2426 | void |
3c0ef626 | 2427 | session_close(Session *s) |
2428 | { | |
34fee935 | 2429 | u_int i; |
1b56ff3d | 2430 | |
ff2d7a98 | 2431 | debug("session_close: session %d pid %ld", s->self, (long)s->pid); |
416fd2a8 | 2432 | if (s->ttyfd != -1) |
3c0ef626 | 2433 | session_pty_cleanup(s); |
3c0ef626 | 2434 | if (s->term) |
2435 | xfree(s->term); | |
2436 | if (s->display) | |
2437 | xfree(s->display); | |
34fee935 | 2438 | if (s->x11_chanids) |
2439 | xfree(s->x11_chanids); | |
e9a17296 | 2440 | if (s->auth_display) |
2441 | xfree(s->auth_display); | |
3c0ef626 | 2442 | if (s->auth_data) |
2443 | xfree(s->auth_data); | |
2444 | if (s->auth_proto) | |
2445 | xfree(s->auth_proto); | |
2446 | s->used = 0; | |
1b56ff3d | 2447 | for (i = 0; i < s->num_env; i++) { |
2448 | xfree(s->env[i].name); | |
2449 | xfree(s->env[i].val); | |
2450 | } | |
2451 | if (s->env != NULL) | |
2452 | xfree(s->env); | |
3c0ef626 | 2453 | session_proctitle(s); |
2454 | } | |
2455 | ||
2456 | void | |
2457 | session_close_by_pid(pid_t pid, int status) | |
2458 | { | |
2459 | Session *s = session_by_pid(pid); | |
2460 | if (s == NULL) { | |
ff2d7a98 | 2461 | debug("session_close_by_pid: no session for pid %ld", |
2462 | (long)pid); | |
3c0ef626 | 2463 | return; |
2464 | } | |
2465 | if (s->chanid != -1) | |
2466 | session_exit_message(s, status); | |
e00da40d | 2467 | if (s->ttyfd != -1) |
2468 | session_pty_cleanup(s); | |
2469 | s->pid = 0; | |
3c0ef626 | 2470 | } |
2471 | ||
2472 | /* | |
2473 | * this is called when a channel dies before | |
2474 | * the session 'child' itself dies | |
2475 | */ | |
2476 | void | |
2477 | session_close_by_channel(int id, void *arg) | |
2478 | { | |
2479 | Session *s = session_by_channel(id); | |
e00da40d | 2480 | u_int i; |
34fee935 | 2481 | |
3c0ef626 | 2482 | if (s == NULL) { |
2483 | debug("session_close_by_channel: no session for id %d", id); | |
2484 | return; | |
2485 | } | |
ff2d7a98 | 2486 | debug("session_close_by_channel: channel %d child %ld", |
2487 | id, (long)s->pid); | |
3c0ef626 | 2488 | if (s->pid != 0) { |
2489 | debug("session_close_by_channel: channel %d: has child", id); | |
2490 | /* | |
2491 | * delay detach of session, but release pty, since | |
2492 | * the fd's to the child are already closed | |
2493 | */ | |
416fd2a8 | 2494 | if (s->ttyfd != -1) |
3c0ef626 | 2495 | session_pty_cleanup(s); |
3c0ef626 | 2496 | return; |
2497 | } | |
2498 | /* detach by removing callback */ | |
2499 | channel_cancel_cleanup(s->chanid); | |
e00da40d | 2500 | |
2501 | /* Close any X11 listeners associated with this session */ | |
2502 | if (s->x11_chanids != NULL) { | |
2503 | for (i = 0; s->x11_chanids[i] != -1; i++) { | |
2504 | session_close_x11(s->x11_chanids[i]); | |
2505 | s->x11_chanids[i] = -1; | |
2506 | } | |
2507 | } | |
2508 | ||
3c0ef626 | 2509 | s->chanid = -1; |
2510 | session_close(s); | |
2511 | } | |
2512 | ||
2513 | void | |
2980ea68 | 2514 | session_destroy_all(void (*closefunc)(Session *)) |
3c0ef626 | 2515 | { |
2516 | int i; | |
e9a17296 | 2517 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 2518 | Session *s = &sessions[i]; |
2980ea68 | 2519 | if (s->used) { |
2520 | if (closefunc != NULL) | |
2521 | closefunc(s); | |
2522 | else | |
2523 | session_close(s); | |
2524 | } | |
3c0ef626 | 2525 | } |
2526 | } | |
2527 | ||
2528 | static char * | |
2529 | session_tty_list(void) | |
2530 | { | |
2531 | static char buf[1024]; | |
2532 | int i; | |
1c14df9e | 2533 | char *cp; |
2534 | ||
3c0ef626 | 2535 | buf[0] = '\0'; |
e9a17296 | 2536 | for (i = 0; i < MAX_SESSIONS; i++) { |
3c0ef626 | 2537 | Session *s = &sessions[i]; |
2538 | if (s->used && s->ttyfd != -1) { | |
416fd2a8 | 2539 | |
1c14df9e | 2540 | if (strncmp(s->tty, "/dev/", 5) != 0) { |
2541 | cp = strrchr(s->tty, '/'); | |
2542 | cp = (cp == NULL) ? s->tty : cp + 1; | |
2543 | } else | |
2544 | cp = s->tty + 5; | |
416fd2a8 | 2545 | |
3c0ef626 | 2546 | if (buf[0] != '\0') |
2547 | strlcat(buf, ",", sizeof buf); | |
1c14df9e | 2548 | strlcat(buf, cp, sizeof buf); |
3c0ef626 | 2549 | } |
2550 | } | |
2551 | if (buf[0] == '\0') | |
2552 | strlcpy(buf, "notty", sizeof buf); | |
2553 | return buf; | |
2554 | } | |
2555 | ||
2556 | void | |
2557 | session_proctitle(Session *s) | |
2558 | { | |
2559 | if (s->pw == NULL) | |
2560 | error("no user for session %d", s->self); | |
2561 | else | |
2562 | setproctitle("%s@%s", s->pw->pw_name, session_tty_list()); | |
2563 | } | |
2564 | ||
2565 | int | |
2566 | session_setup_x11fwd(Session *s) | |
2567 | { | |
2568 | struct stat st; | |
e9a17296 | 2569 | char display[512], auth_display[512]; |
2570 | char hostname[MAXHOSTNAMELEN]; | |
34fee935 | 2571 | u_int i; |
3c0ef626 | 2572 | |
2573 | if (no_x11_forwarding_flag) { | |
2574 | packet_send_debug("X11 forwarding disabled in user configuration file."); | |
2575 | return 0; | |
2576 | } | |
2577 | if (!options.x11_forwarding) { | |
2578 | debug("X11 forwarding disabled in server configuration file."); | |
2579 | return 0; | |
2580 | } | |
2581 | if (!options.xauth_location || | |
2582 | (stat(options.xauth_location, &st) == -1)) { | |
2583 | packet_send_debug("No xauth program; cannot forward with spoofing."); | |
2584 | return 0; | |
2585 | } | |
2586 | if (options.use_login) { | |
2587 | packet_send_debug("X11 forwarding disabled; " | |
2588 | "not compatible with UseLogin=yes."); | |
2589 | return 0; | |
2590 | } | |
2591 | if (s->display != NULL) { | |
2592 | debug("X11 display already set."); | |
2593 | return 0; | |
2594 | } | |
ff2d7a98 | 2595 | if (x11_create_display_inet(options.x11_display_offset, |
2596 | options.x11_use_localhost, s->single_connection, | |
e00da40d | 2597 | &s->display_number, &s->x11_chanids, |
2598 | options.hpn_disabled, options.hpn_buffer_size) == -1) { | |
3c0ef626 | 2599 | debug("x11_create_display_inet failed."); |
2600 | return 0; | |
2601 | } | |
34fee935 | 2602 | for (i = 0; s->x11_chanids[i] != -1; i++) { |
2603 | channel_register_cleanup(s->x11_chanids[i], | |
e00da40d | 2604 | session_close_single_x11, 0); |
34fee935 | 2605 | } |
e9a17296 | 2606 | |
2607 | /* Set up a suitable value for the DISPLAY variable. */ | |
2608 | if (gethostname(hostname, sizeof(hostname)) < 0) | |
2609 | fatal("gethostname: %.100s", strerror(errno)); | |
2610 | /* | |
2611 | * auth_display must be used as the displayname when the | |
2612 | * authorization entry is added with xauth(1). This will be | |
2613 | * different than the DISPLAY string for localhost displays. | |
2614 | */ | |
2615 | if (options.x11_use_localhost) { | |
ff2d7a98 | 2616 | snprintf(display, sizeof display, "localhost:%u.%u", |
e9a17296 | 2617 | s->display_number, s->screen); |
ff2d7a98 | 2618 | snprintf(auth_display, sizeof auth_display, "unix:%u.%u", |
e9a17296 | 2619 | s->display_number, s->screen); |
2620 | s->display = xstrdup(display); | |
2621 | s->auth_display = xstrdup(auth_display); | |
2622 | } else { | |
2623 | #ifdef IPADDR_IN_DISPLAY | |
2624 | struct hostent *he; | |
2625 | struct in_addr my_addr; | |
2626 | ||
2627 | he = gethostbyname(hostname); | |
2628 | if (he == NULL) { | |
2629 | error("Can't get IP address for X11 DISPLAY."); | |
2630 | packet_send_debug("Can't get IP address for X11 DISPLAY."); | |
2631 | return 0; | |
2632 | } | |
2633 | memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr)); | |
ff2d7a98 | 2634 | snprintf(display, sizeof display, "%.50s:%u.%u", inet_ntoa(my_addr), |
e9a17296 | 2635 | s->display_number, s->screen); |
2636 | #else | |
ff2d7a98 | 2637 | snprintf(display, sizeof display, "%.400s:%u.%u", hostname, |
e9a17296 | 2638 | s->display_number, s->screen); |
2639 | #endif | |
2640 | s->display = xstrdup(display); | |
2641 | s->auth_display = xstrdup(display); | |
2642 | } | |
2643 | ||
3c0ef626 | 2644 | return 1; |
2645 | } | |
2646 | ||
2647 | static void | |
2648 | do_authenticated2(Authctxt *authctxt) | |
2649 | { | |
2650 | server_loop2(authctxt); | |
416fd2a8 | 2651 | } |
2652 | ||
2653 | void | |
2654 | do_cleanup(Authctxt *authctxt) | |
2655 | { | |
2656 | static int called = 0; | |
2657 | ||
2658 | debug("do_cleanup"); | |
2659 | ||
2660 | /* no cleanup if we're in the child for login shell */ | |
2661 | if (is_child) | |
2662 | return; | |
2663 | ||
2664 | /* avoid double cleanup */ | |
2665 | if (called) | |
2666 | return; | |
2667 | called = 1; | |
2668 | ||
2669 | if (authctxt == NULL) | |
2670 | return; | |
2671 | #ifdef KRB5 | |
2672 | if (options.kerberos_ticket_cleanup && | |
2673 | authctxt->krb5_ctx) | |
2674 | krb5_cleanup_proc(authctxt); | |
2675 | #endif | |
2676 | ||
2677 | #ifdef GSSAPI | |
2678 | if (compat20 && options.gss_cleanup_creds) | |
2679 | ssh_gssapi_cleanup_creds(); | |
b9a54c29 | 2680 | #endif |
416fd2a8 | 2681 | |
2682 | #ifdef USE_PAM | |
2683 | if (options.use_pam) { | |
2684 | sshpam_cleanup(); | |
2685 | sshpam_thread_cleanup(); | |
2686 | } | |
2687 | #endif | |
2688 | ||
2689 | /* remove agent socket */ | |
2690 | auth_sock_cleanup_proc(authctxt->pw); | |
2691 | ||
2692 | /* | |
2693 | * Cleanup ptys/utmp only if privsep is disabled, | |
2694 | * or if running in monitor. | |
2695 | */ | |
2696 | if (!use_privsep || mm_is_monitor()) | |
2697 | session_destroy_all(session_pty_cleanup2); | |
3c0ef626 | 2698 | } |