1 /*
2 * Copyright (c) 1997-2006 Erez Zadok
3 * Copyright (c) 1989 Jan-Simon Pendry
4 * Copyright (c) 1989 Imperial College of Science, Technology & Medicine
5 * Copyright (c) 1989 The Regents of the University of California.
6 * All rights reserved.
7 *
8 * This code is derived from software contributed to Berkeley by
9 * Jan-Simon Pendry at Imperial College, London.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgment:
21 * This product includes software developed by the University of
22 * California, Berkeley and its contributors.
23 * 4. Neither the name of the University nor the names of its contributors
24 * may be used to endorse or promote products derived from this software
25 * without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * SUCH DAMAGE.
38 *
39 *
40 * $Id: amd.c,v 1.8.2.6 2004/01/06 03:15:16 ezk Exp $
41 * File: am-utils/amd/amd.c
42 *
43 */
44
45 #include <sys/cdefs.h>
46 __FBSDID("$FreeBSD$");
47
48 /*
49 * Automounter
50 */
51
52 #ifdef HAVE_CONFIG_H
53 # include <config.h>
54 #endif /* HAVE_CONFIG_H */
55 #include <am_defs.h>
56 #include <amd.h>
57
58 struct amu_global_options gopt; /* where global options are stored */
59
60 char pid_fsname[SIZEOF_PID_FSNAME]; /* "kiska.southseas.nz:(pid%d)" */
61 char *hostdomain = "unknown.domain";
62 #define SIZEOF_HOSTD (2 * MAXHOSTNAMELEN + 1) /* Host+domain */
63 char hostd[SIZEOF_HOSTD]; /* Host+domain */
64 char *endian = ARCH_ENDIAN; /* Big or Little endian */
65 char *cpu = HOST_CPU; /* CPU type */
66 char *PrimNetName; /* name of primary network */
67 char *PrimNetNum; /* number of primary network */
68
69 int immediate_abort; /* Should close-down unmounts be retried */
70 int orig_umask = 022;
71 int select_intr_valid;
72
73 jmp_buf select_intr;
74 struct amd_stats amd_stats; /* Server statistics */
75 struct in_addr myipaddr; /* (An) IP address of this host */
76 time_t do_mapc_reload = 0; /* mapc_reload() call required? */
77
78 #ifdef HAVE_FS_AUTOFS
79 int amd_use_autofs = 0;
80 #endif /* HAVE_FS_AUTOFS */
81
82 #ifdef HAVE_SIGACTION
83 sigset_t masked_sigs;
84 #endif /* HAVE_SIGACTION */
85
86
87 /*
88 * Signal handler:
89 * SIGINT - tells amd to do a full shutdown, including unmounting all
90 * filesystem.
91 * SIGTERM - tells amd to shutdown now. Just unmounts the automount nodes.
92 */
93 static RETSIGTYPE
sigterm(int sig)94 sigterm(int sig)
95 {
96 #ifdef REINSTALL_SIGNAL_HANDLER
97 signal(sig, sigterm);
98 #endif /* REINSTALL_SIGNAL_HANDLER */
99
100 switch (sig) {
101 case SIGINT:
102 immediate_abort = 15;
103 break;
104
105 case SIGTERM:
106 immediate_abort = -1;
107 /* fall through... */
108
109 default:
110 plog(XLOG_WARNING, "WARNING: automounter going down on signal %d", sig);
111 break;
112 }
113 if (select_intr_valid)
114 longjmp(select_intr, sig);
115 }
116
117
118 /*
119 * Hook for cache reload.
120 * When a SIGHUP arrives it schedules a call to mapc_reload
121 */
122 static RETSIGTYPE
sighup(int sig)123 sighup(int sig)
124 {
125 #ifdef REINSTALL_SIGNAL_HANDLER
126 signal(sig, sighup);
127 #endif /* REINSTALL_SIGNAL_HANDLER */
128
129 if (sig != SIGHUP)
130 dlog("spurious call to sighup");
131 /*
132 * Force a reload by zero'ing the timer
133 */
134 if (amd_state == Run)
135 do_mapc_reload = 0;
136 }
137
138
139 static RETSIGTYPE
parent_exit(int sig)140 parent_exit(int sig)
141 {
142 /*
143 * This signal handler is called during Amd initialization. The parent
144 * forks a child to do all the hard automounting work, and waits for a
145 * SIGQUIT signal from the child. When the parent gets the signal it's
146 * supposed to call this handler and exit(3), thus completing the
147 * daemonizing process. Alas, on some systems, especially Linux 2.4/2.6
148 * with Glibc, exit(3) doesn't always terminate the parent process.
149 * Worse, the parent process now refuses to accept any more SIGQUIT
150 * signals -- they are blocked. What's really annoying is that this
151 * doesn't happen all the time, suggesting a race condition somewhere.
152 * (This happens even if I change the logic to use another signal.) I
153 * traced this to something which exit(3) does in addition to exiting the
154 * process, probably some atexit() stuff or other side-effects related to
155 * signal handling. Either way, since at this stage the parent process
156 * just needs to terminate, I'm simply calling _exit(2). Note also that
157 * the OpenGroup doesn't list exit(3) as a recommended "Base Interface"
158 * but they do list _exit(2) as one. This fix seems to work reliably all
159 * the time. -Erez (2/27/2005)
160 */
161 _exit(0);
162 }
163
164
165 static int
daemon_mode(void)166 daemon_mode(void)
167 {
168 int bgpid;
169
170 #ifdef HAVE_SIGACTION
171 struct sigaction sa, osa;
172
173 memset(&sa, 0, sizeof(sa));
174 sa.sa_handler = parent_exit;
175 sa.sa_flags = 0;
176 sigemptyset(&(sa.sa_mask));
177 sigaddset(&(sa.sa_mask), SIGQUIT);
178 sigaction(SIGQUIT, &sa, &osa);
179 #else /* not HAVE_SIGACTION */
180 signal(SIGQUIT, parent_exit);
181 #endif /* not HAVE_SIGACTION */
182
183 bgpid = background();
184
185 if (bgpid != 0) {
186 /*
187 * Now wait for the automount points to
188 * complete.
189 */
190 for (;;)
191 pause();
192 /* should never reach here */
193 }
194 #ifdef HAVE_SIGACTION
195 sigaction(SIGQUIT, &osa, NULL);
196 #else /* not HAVE_SIGACTION */
197 signal(SIGQUIT, SIG_DFL);
198 #endif /* not HAVE_SIGACTION */
199
200 /*
201 * Record our pid to make it easier to kill the correct amd.
202 */
203 if (gopt.flags & CFM_PRINT_PID) {
204 if (STREQ(gopt.pid_file, "/dev/stdout")) {
205 printf("%ld\n", (long) am_mypid);
206 /* flush stdout, just in case */
207 fflush(stdout);
208 } else {
209 FILE *f;
210 mode_t prev_umask = umask(0022); /* set secure temporary umask */
211
212 f = fopen(gopt.pid_file, "w");
213 if (f) {
214 fprintf(f, "%ld\n", (long) am_mypid);
215 (void) fclose(f);
216 } else {
217 fprintf(stderr, "cannot open %s (errno=%d)\n", gopt.pid_file, errno);
218 }
219 umask(prev_umask); /* restore umask */
220 }
221 }
222
223 /*
224 * Pretend we are in the foreground again
225 */
226 foreground = 1;
227
228 /*
229 * Dissociate from the controlling terminal
230 */
231 amu_release_controlling_tty();
232
233 return getppid();
234 }
235
236
237 /*
238 * Initialize global options structure.
239 */
240 static void
init_global_options(void)241 init_global_options(void)
242 {
243 #if defined(HAVE_SYS_UTSNAME_H) && defined(HAVE_UNAME)
244 static struct utsname un;
245 #endif /* defined(HAVE_SYS_UTSNAME_H) && defined(HAVE_UNAME) */
246 int i;
247
248 memset(&gopt, 0, sizeof(struct amu_global_options));
249
250 /* name of current architecture */
251 gopt.arch = HOST_ARCH;
252
253 /* automounter temp dir */
254 gopt.auto_dir = "/.amd_mnt";
255
256 /* toplevel attribute cache timeout */
257 gopt.auto_attrcache = 0;
258
259 /* cluster name */
260 gopt.cluster = NULL;
261
262 /* executable map timeout */
263 gopt.exec_map_timeout = AMFS_EXEC_MAP_TIMEOUT;
264
265 /*
266 * kernel architecture: this you must get from uname() if possible.
267 */
268 #if defined(HAVE_SYS_UTSNAME_H) && defined(HAVE_UNAME)
269 if (uname(&un) >= 0)
270 gopt.karch = un.machine;
271 else
272 #endif /* defined(HAVE_SYS_UTSNAME_H) && defined(HAVE_UNAME) */
273 gopt.karch = HOST_ARCH;
274
275 /* amd log file */
276 gopt.logfile = NULL;
277
278 /* operating system name */
279 gopt.op_sys = HOST_OS_NAME;
280
281 /* OS version */
282 gopt.op_sys_ver = HOST_OS_VERSION;
283
284 /* full OS name and version */
285 gopt.op_sys_full = HOST_OS;
286
287 /* OS version */
288 gopt.op_sys_vendor = HOST_VENDOR;
289
290 /* pid file */
291 gopt.pid_file = "/dev/stdout";
292
293 /* local domain */
294 gopt.sub_domain = NULL;
295
296 /* reset NFS (and toplvl) retransmit counter and retry interval */
297 for (i=0; i<AMU_TYPE_MAX; ++i) {
298 gopt.amfs_auto_retrans[i] = -1; /* -1 means "never set before" */
299 gopt.amfs_auto_timeo[i] = -1; /* -1 means "never set before" */
300 }
301
302 /* cache duration */
303 gopt.am_timeo = AM_TTL;
304
305 /* dismount interval */
306 gopt.am_timeo_w = AM_TTL_W;
307
308 /* map reload intervl */
309 gopt.map_reload_interval = ONE_HOUR;
310
311 /*
312 * various CFM_* flags that are on by default.
313 */
314 gopt.flags = CFM_DEFAULT_FLAGS;
315
316 #ifdef HAVE_MAP_HESIOD
317 /* Hesiod rhs zone */
318 gopt.hesiod_base = "automount";
319 #endif /* HAVE_MAP_HESIOD */
320
321 #ifdef HAVE_MAP_LDAP
322 /* LDAP base */
323 gopt.ldap_base = NULL;
324
325 /* LDAP host ports */
326 gopt.ldap_hostports = NULL;
327
328 /* LDAP cache */
329 gopt.ldap_cache_seconds = 0;
330 gopt.ldap_cache_maxmem = 131072;
331
332 /* LDAP protocol version */
333 gopt.ldap_proto_version = 2;
334 #endif /* HAVE_MAP_LDAP */
335
336 #ifdef HAVE_MAP_NIS
337 /* YP domain name */
338 gopt.nis_domain = NULL;
339 #endif /* HAVE_MAP_NIS */
340 }
341
342
343 /*
344 * Lock process text and data segment in memory (after forking the daemon)
345 */
346 static void
do_memory_locking(void)347 do_memory_locking(void)
348 {
349 #if defined(HAVE_PLOCK) || defined(HAVE_MLOCKALL)
350 int locked_ok = 0;
351 #else /* not HAVE_PLOCK and not HAVE_MLOCKALL */
352 plog(XLOG_WARNING, "Process memory locking not supported by the OS");
353 #endif /* not HAVE_PLOCK and not HAVE_MLOCKALL */
354 #ifdef HAVE_PLOCK
355 # ifdef _AIX
356 /*
357 * On AIX you must lower the stack size using ulimit() before calling
358 * plock. Otherwise plock will reserve a lot of memory space based on
359 * your maximum stack size limit. Since it is not easily possible to
360 * tell what should the limit be, I print a warning before calling
361 * plock(). See the manual pages for ulimit(1,3,4) on your AIX system.
362 */
363 plog(XLOG_WARNING, "AIX: may need to lower stack size using ulimit(3) before calling plock");
364 # endif /* _AIX */
365 if (!locked_ok && plock(PROCLOCK) != 0)
366 plog(XLOG_WARNING, "Couldn't lock process pages in memory using plock(): %m");
367 else
368 locked_ok = 1;
369 #endif /* HAVE_PLOCK */
370 #ifdef HAVE_MLOCKALL
371 if (!locked_ok && mlockall(MCL_CURRENT|MCL_FUTURE) != 0)
372 plog(XLOG_WARNING, "Couldn't lock process pages in memory using mlockall(): %m");
373 else
374 locked_ok = 1;
375 #endif /* HAVE_MLOCKALL */
376 #if defined(HAVE_PLOCK) || defined(HAVE_MLOCKALL)
377 if (locked_ok)
378 plog(XLOG_INFO, "Locked process pages in memory");
379 #endif /* HAVE_PLOCK || HAVE_MLOCKALL */
380
381 #if defined(HAVE_MADVISE) && defined(MADV_PROTECT)
382 madvise(0, 0, MADV_PROTECT); /* may be redundant of the above worked out */
383 #endif /* defined(HAVE_MADVISE) && defined(MADV_PROTECT) */
384 }
385
386
387 int
main(int argc,char * argv[])388 main(int argc, char *argv[])
389 {
390 char *domdot, *verstr, *vertmp;
391 int ppid = 0;
392 int error;
393 char *progname = NULL; /* "amd" */
394 char hostname[MAXHOSTNAMELEN + 1] = "localhost"; /* Hostname */
395
396 /*
397 * Make sure some built-in assumptions are true before we start
398 */
399 assert(sizeof(nfscookie) >= sizeof(u_int));
400 assert(sizeof(int) >= 4);
401
402 /*
403 * Set processing status.
404 */
405 amd_state = Start;
406
407 /*
408 * Determine program name
409 */
410 if (argv[0]) {
411 progname = strrchr(argv[0], '/');
412 if (progname && progname[1])
413 progname++;
414 else
415 progname = argv[0];
416 }
417 if (!progname)
418 progname = "amd";
419 am_set_progname(progname);
420
421 /*
422 * Initialize process id. This is kept
423 * cached since it is used for generating
424 * and using file handles.
425 */
426 am_set_mypid();
427
428 /*
429 * Get local machine name
430 */
431 if (gethostname(hostname, sizeof(hostname)) < 0) {
432 plog(XLOG_FATAL, "gethostname: %m");
433 going_down(1);
434 }
435 hostname[sizeof(hostname) - 1] = '\0';
436
437 /*
438 * Check it makes sense
439 */
440 if (!*hostname) {
441 plog(XLOG_FATAL, "host name is not set");
442 going_down(1);
443 }
444
445 /*
446 * Initialize global options structure.
447 */
448 init_global_options();
449
450 /*
451 * Partially initialize hostd[]. This
452 * is completed in get_args().
453 */
454 if ((domdot = strchr(hostname, '.'))) {
455 /*
456 * Hostname already contains domainname.
457 * Split out hostname and domainname
458 * components
459 */
460 *domdot++ = '\0';
461 hostdomain = domdot;
462 }
463 xstrlcpy(hostd, hostname, sizeof(hostd));
464 am_set_hostname(hostname);
465
466 /*
467 * Setup signal handlers
468 */
469 /* SIGINT: trap interrupts for shutdowns */
470 setup_sighandler(SIGINT, sigterm);
471 /* SIGTERM: trap terminate so we can shutdown cleanly (some chance) */
472 setup_sighandler(SIGTERM, sigterm);
473 /* SIGHUP: hangups tell us to reload the cache */
474 setup_sighandler(SIGHUP, sighup);
475 /*
476 * SIGCHLD: trap Death-of-a-child. These allow us to pick up the exit
477 * status of backgrounded mounts. See "sched.c".
478 */
479 setup_sighandler(SIGCHLD, sigchld);
480 #ifdef HAVE_SIGACTION
481 /* construct global "masked_sigs" used in nfs_start.c */
482 sigemptyset(&masked_sigs);
483 sigaddset(&masked_sigs, SIGINT);
484 sigaddset(&masked_sigs, SIGTERM);
485 sigaddset(&masked_sigs, SIGHUP);
486 sigaddset(&masked_sigs, SIGCHLD);
487 #endif /* HAVE_SIGACTION */
488
489 /*
490 * Fix-up any umask problems. Most systems default
491 * to 002 which is not too convenient for our purposes
492 */
493 orig_umask = umask(0);
494
495 /*
496 * Figure out primary network name
497 */
498 getwire(&PrimNetName, &PrimNetNum);
499
500 /*
501 * Determine command-line arguments
502 */
503 get_args(argc, argv);
504
505 /*
506 * Log version information.
507 */
508 vertmp = get_version_string();
509 verstr = strtok(vertmp, "\n");
510 plog(XLOG_INFO, "AM-UTILS VERSION INFORMATION:");
511 while (verstr) {
512 plog(XLOG_INFO, "%s", verstr);
513 verstr = strtok(NULL, "\n");
514 }
515 XFREE(vertmp);
516
517 /*
518 * Get our own IP address so that we can mount the automounter. We pass
519 * localhost_address which could be used as the default localhost
520 * name/address in amu_get_myaddress().
521 */
522 amu_get_myaddress(&myipaddr, gopt.localhost_address);
523 plog(XLOG_INFO, "My ip addr is %s", inet_ntoa(myipaddr));
524
525 /* avoid hanging on other NFS servers if started elsewhere */
526 if (chdir("/") < 0)
527 plog(XLOG_INFO, "cannot chdir to /: %m");
528
529 /*
530 * Now check we are root.
531 */
532 if (geteuid() != 0) {
533 plog(XLOG_FATAL, "Must be root to mount filesystems (euid = %ld)", (long) geteuid());
534 going_down(1);
535 }
536
537 #ifdef HAVE_MAP_NIS
538 /*
539 * If the domain was specified then bind it here
540 * to circumvent any default bindings that may
541 * be done in the C library.
542 */
543 if (gopt.nis_domain && yp_bind(gopt.nis_domain)) {
544 plog(XLOG_FATAL, "Can't bind to NIS domain \"%s\"", gopt.nis_domain);
545 going_down(1);
546 }
547 #endif /* HAVE_MAP_NIS */
548
549 if (!amuDebug(D_DAEMON))
550 ppid = daemon_mode();
551
552 /*
553 * Lock process text and data segment in memory.
554 */
555 if (gopt.flags & CFM_PROCESS_LOCK) {
556 do_memory_locking();
557 }
558
559 do_mapc_reload = clocktime(NULL) + gopt.map_reload_interval;
560
561 /*
562 * Register automounter with system.
563 */
564 error = mount_automounter(ppid);
565 if (error && ppid)
566 kill(ppid, SIGALRM);
567
568 #ifdef HAVE_FS_AUTOFS
569 /*
570 * XXX this should be part of going_down(), but I can't move it there
571 * because it would be calling non-library code from the library... ugh
572 */
573 if (amd_use_autofs)
574 destroy_autofs_service();
575 #endif /* HAVE_FS_AUTOFS */
576
577 going_down(error);
578
579 abort();
580 return 1; /* should never get here */
581 }
582