2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 2014 The FreeBSD Foundation
7 * This software was developed by Edward Tomasz Napierala under sponsorship
8 * from the FreeBSD Foundation.
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
36 #include <sys/types.h>
38 #include <sys/ioctl.h>
39 #include <sys/param.h>
40 #include <sys/linker.h>
41 #include <sys/mount.h>
42 #include <sys/socket.h>
45 #include <sys/utsname.h>
61 #include "autofs_ioctl.h"
65 #define AUTOMOUNTD_PIDFILE "/var/run/automountd.pid"
67 static int nchildren = 0;
69 static int request_id;
72 done(int request_error, bool wildcards)
74 struct autofs_daemon_done add;
77 memset(&add, 0, sizeof(add));
78 add.add_id = request_id;
79 add.add_wildcards = wildcards;
80 add.add_error = request_error;
82 log_debugx("completing request %d with error %d",
83 request_id, request_error);
85 error = ioctl(autofs_fd, AUTOFSDONE, &add);
87 log_warn("AUTOFSDONE");
91 * Remove "fstype=whatever" from optionsp and return the "whatever" part.
94 pick_option(const char *option, char **optionsp)
96 char *tofree, *pair, *newoptions;
102 newoptions = calloc(1, strlen(*optionsp) + 1);
103 if (newoptions == NULL)
104 log_err(1, "calloc");
106 while ((pair = strsep(optionsp, ",")) != NULL) {
108 * XXX: strncasecmp(3) perhaps?
110 if (strncmp(pair, option, strlen(option)) == 0) {
111 picked = checked_strdup(pair + strlen(option));
114 strcat(newoptions, ",");
117 strcat(newoptions, pair);
122 *optionsp = newoptions;
128 create_subtree(const struct node *node, bool incomplete)
130 const struct node *child;
132 bool wildcard_found = false;
135 * Skip wildcard nodes.
137 if (strcmp(node->n_key, "*") == 0)
140 path = node_path(node);
141 log_debugx("creating subtree at %s", path);
142 create_directory(path);
145 TAILQ_FOREACH(child, &node->n_children, n_next) {
146 if (strcmp(child->n_key, "*") == 0) {
147 wildcard_found = true;
152 if (wildcard_found) {
153 log_debugx("node %s contains wildcard entry; "
154 "not creating its subdirectories due to -d flag",
163 TAILQ_FOREACH(child, &node->n_children, n_next)
164 create_subtree(child, incomplete);
175 handle_request(const struct autofs_daemon_request *adr, char *cmdline_options,
176 bool incomplete_hierarchy)
179 struct node *root, *parent, *node;
181 char *key, *options, *fstype, *nobrowse, *retrycnt, *tmp;
185 log_debugx("got request %d: from %s, path %s, prefix \"%s\", "
186 "key \"%s\", options \"%s\"", adr->adr_id, adr->adr_from,
187 adr->adr_path, adr->adr_prefix, adr->adr_key, adr->adr_options);
190 * Try to notify the kernel about any problems.
192 request_id = adr->adr_id;
193 atexit(exit_callback);
195 if (strncmp(adr->adr_from, "map ", 4) != 0) {
196 log_errx(1, "invalid mountfrom \"%s\"; failing request",
200 map = adr->adr_from + 4; /* 4 for strlen("map "); */
201 root = node_new_root();
202 if (adr->adr_prefix[0] == '\0' || strcmp(adr->adr_prefix, "/") == 0) {
204 * Direct map. autofs(4) doesn't have a way to determine
205 * correct map key, but since it's a direct map, we can just
206 * use adr_path instead.
209 key = checked_strdup(adr->adr_path);
214 parent = node_new_map(root, checked_strdup(adr->adr_prefix),
215 NULL, checked_strdup(map),
216 checked_strdup("[kernel request]"), lineno);
218 if (adr->adr_key[0] == '\0')
221 key = checked_strdup(adr->adr_key);
225 * "Wildcards" here actually means "make autofs(4) request
226 * automountd(8) action if the node being looked up does not
227 * exist, even though the parent is marked as cached". This
228 * needs to be done for maps with wildcard entries, but also
229 * for special and executable maps.
231 parse_map(parent, map, key, &wildcards);
233 wildcards = node_has_wildcards(parent);
235 log_debugx("map may contain wildcard entries");
237 log_debugx("map does not contain wildcard entries");
240 node_expand_wildcard(root, key);
242 node = node_find(root, adr->adr_path);
244 log_errx(1, "map %s does not contain key for \"%s\"; "
245 "failing mount", map, adr->adr_path);
248 options = node_options(node);
251 * Append options from auto_master.
253 options = concat(options, ',', adr->adr_options);
256 * Prepend options passed via automountd(8) command line.
258 options = concat(cmdline_options, ',', options);
260 if (node->n_location == NULL) {
261 log_debugx("found node defined at %s:%d; not a mountpoint",
262 node->n_config_file, node->n_config_line);
264 nobrowse = pick_option("nobrowse", &options);
265 if (nobrowse != NULL && key == NULL) {
266 log_debugx("skipping map %s due to \"nobrowse\" "
267 "option; exiting", map);
271 * Exit without calling exit_callback().
277 * Not a mountpoint; create directories in the autofs mount
278 * and complete the request.
280 create_subtree(node, incomplete_hierarchy);
282 if (incomplete_hierarchy && key != NULL) {
284 * We still need to create the single subdirectory
285 * user is trying to access.
287 tmp = concat(adr->adr_path, '/', key);
288 node = node_find(root, tmp);
290 create_subtree(node, false);
293 log_debugx("nothing to mount; exiting");
297 * Exit without calling exit_callback().
302 log_debugx("found node defined at %s:%d; it is a mountpoint",
303 node->n_config_file, node->n_config_line);
306 node_expand_ampersand(node, key);
307 error = node_expand_defined(node);
309 log_errx(1, "variable expansion failed for %s; "
310 "failing mount", adr->adr_path);
314 * Append "automounted".
316 options = concat(options, ',', "automounted");
319 * Remove "nobrowse", mount(8) doesn't understand it.
321 pick_option("nobrowse", &options);
326 fstype = pick_option("fstype=", &options);
327 if (fstype == NULL) {
328 log_debugx("fstype not specified in options; "
329 "defaulting to \"nfs\"");
330 fstype = checked_strdup("nfs");
333 if (strcmp(fstype, "nfs") == 0) {
335 * The mount_nfs(8) command defaults to retry undefinitely.
336 * We do not want that behaviour, because it leaves mount_nfs(8)
337 * instances and automountd(8) children hanging forever.
338 * Disable retries unless the option was passed explicitly.
340 retrycnt = pick_option("retrycnt=", &options);
341 if (retrycnt == NULL) {
342 log_debugx("retrycnt not specified in options; "
344 options = concat(options, ',', "retrycnt=1");
346 options = concat(options, ',',
347 concat("retrycnt", '=', retrycnt));
351 f = auto_popen("mount", "-t", fstype, "-o", options,
352 node->n_location, adr->adr_path, NULL);
354 error = auto_pclose(f);
356 log_errx(1, "mount failed");
358 log_debugx("mount done; exiting");
362 * Exit without calling exit_callback().
368 sigchld_handler(int dummy __unused)
372 * The only purpose of this handler is to make SIGCHLD
373 * interrupt the AUTOFSREQUEST ioctl(2), so we can call
374 * wait_for_children().
379 register_sigchld(void)
384 bzero(&sa, sizeof(sa));
385 sa.sa_handler = sigchld_handler;
386 sigfillset(&sa.sa_mask);
387 error = sigaction(SIGCHLD, &sa, NULL);
389 log_err(1, "sigaction");
395 wait_for_children(bool block)
403 * If "block" is true, wait for at least one process.
405 if (block && num == 0)
406 pid = wait4(-1, &status, 0, NULL);
408 pid = wait4(-1, &status, WNOHANG, NULL);
411 if (WIFSIGNALED(status)) {
412 log_warnx("child process %d terminated with signal %d",
413 pid, WTERMSIG(status));
414 } else if (WEXITSTATUS(status) != 0) {
415 log_debugx("child process %d terminated with exit status %d",
416 pid, WEXITSTATUS(status));
418 log_debugx("child process %d terminated gracefully", pid);
427 usage_automountd(void)
430 fprintf(stderr, "usage: automountd [-D name=value][-m maxproc]"
431 "[-o opts][-Tidv]\n");
436 main_automountd(int argc, char **argv)
440 const char *pidfile_path = AUTOMOUNTD_PIDFILE;
441 char *options = NULL;
442 struct autofs_daemon_request request;
443 int ch, debug = 0, error, maxproc = 30, retval, saved_errno;
444 bool dont_daemonize = false, incomplete_hierarchy = false;
448 while ((ch = getopt(argc, argv, "D:Tdim:o:v")) != -1) {
451 defined_parse_and_add(optarg);
455 * For compatibility with other implementations,
461 dont_daemonize = true;
465 incomplete_hierarchy = true;
468 maxproc = atoi(optarg);
471 options = concat(options, ',', optarg);
487 pidfh = pidfile_open(pidfile_path, 0600, &otherpid);
489 if (errno == EEXIST) {
490 log_errx(1, "daemon already running, pid: %jd.",
493 log_err(1, "cannot open or create pidfile \"%s\"",
497 autofs_fd = open(AUTOFS_PATH, O_RDWR | O_CLOEXEC);
498 if (autofs_fd < 0 && errno == ENOENT) {
500 retval = kldload("autofs");
502 autofs_fd = open(AUTOFS_PATH, O_RDWR | O_CLOEXEC);
507 log_err(1, "failed to open %s", AUTOFS_PATH);
509 if (dont_daemonize == false) {
510 if (daemon(0, 0) == -1) {
511 log_warn("cannot daemonize");
512 pidfile_remove(pidfh);
519 pidfile_write(pidfh);
524 log_debugx("waiting for request from the kernel");
526 memset(&request, 0, sizeof(request));
527 error = ioctl(autofs_fd, AUTOFSREQUEST, &request);
529 if (errno == EINTR) {
530 nchildren -= wait_for_children(false);
531 assert(nchildren >= 0);
535 log_err(1, "AUTOFSREQUEST");
538 if (dont_daemonize) {
539 log_debugx("not forking due to -d flag; "
540 "will exit after servicing a single request");
542 nchildren -= wait_for_children(false);
543 assert(nchildren >= 0);
545 while (maxproc > 0 && nchildren >= maxproc) {
546 log_debugx("maxproc limit of %d child processes hit; "
547 "waiting for child process to exit", maxproc);
548 nchildren -= wait_for_children(true);
549 assert(nchildren >= 0);
551 log_debugx("got request; forking child process #%d",
562 pidfile_close(pidfh);
563 handle_request(&request, options, incomplete_hierarchy);
566 pidfile_close(pidfh);