/* $NetBSD: automount.c,v 1.3 2018/01/15 14:38:06 christos Exp $ */ /*- * Copyright (c) 2017 The NetBSD Foundation, Inc. * Copyright (c) 2016 The DragonFly Project * Copyright (c) 2014 The FreeBSD Foundation * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Tomohiro Kusumi . * * This software was developed by Edward Tomasz Napierala under sponsorship * from the FreeBSD Foundation. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include __RCSID("$NetBSD: automount.c,v 1.3 2018/01/15 14:38:06 christos Exp $"); #include #include #include #include #include #include #include #include #include "common.h" static int unmount_by_statfs(const struct statvfs *sb, bool force) { int error, flags; log_debugx("unmounting %s", sb->f_mntonname); flags = 0; if (force) flags |= MNT_FORCE; error = unmount(sb->f_mntonname, flags); if (error != 0) log_warn("cannot unmount %s", sb->f_mntonname); return error; } static const struct statvfs * find_statfs(const struct statvfs *mntbuf, int nitems, const char *mountpoint) { int i; for (i = 0; i < nitems; i++) { if (strcmp(mntbuf[i].f_mntonname, mountpoint) == 0) return mntbuf + i; } return NULL; } static void mount_autofs(const char *from, const char *fspath, const char *options, const char *prefix) { struct autofs_args args; int error; char *cwd; /* * There is no guarantee we are at /, so chdir to /. */ cwd = getcwd(NULL, 0); if (chdir("/") != 0) log_warn("failed to chdir to /"); create_directory(fspath); if (chdir(cwd) != 0) log_warn("failed to restore cwd"); free(cwd); log_debugx("mounting %s on %s, prefix \"%s\", options \"%s\"", from, fspath, prefix, options); memset(&args, 0, sizeof(args)); args.from = __UNCONST(from); args.master_options = __UNCONST(options); args.master_prefix = __UNCONST(prefix); error = mount("autofs", fspath, 0, &args, sizeof(args)); if (error != 0) log_err(1, "cannot mount %s on %s", from, fspath); } static void mount_if_not_already(const struct node *n, const char *map, const char *options, const char *prefix, const struct statvfs *mntbuf, int nitems) { const struct statvfs *sb; char *mountpoint; char *from; int ret; ret = asprintf(&from, "map %s", map); if (ret < 0) log_err(1, "asprintf"); mountpoint = node_path(n); sb = find_statfs(mntbuf, nitems, mountpoint); if (sb != NULL) { if (strcmp(sb->f_fstypename, "autofs") != 0) { log_debugx("unknown filesystem mounted " "on %s; mounting", mountpoint); /* * XXX: Compare options and 'from', * and update the mount if necessary. */ } else { log_debugx("autofs already mounted " "on %s", mountpoint); free(from); free(mountpoint); return; } } else { log_debugx("nothing mounted on %s; mounting", mountpoint); } mount_autofs(from, mountpoint, options, prefix); free(from); free(mountpoint); } static void mount_unmount(struct node *root) { struct statvfs *mntbuf; struct node *n, *n2; int i, nitems; static char rootdir[] = "/"; nitems = getmntinfo(&mntbuf, MNT_WAIT); if (nitems <= 0) log_err(1, "getmntinfo"); log_debugx("unmounting stale autofs mounts"); for (i = 0; i < nitems; i++) { if (strcmp(mntbuf[i].f_fstypename, "autofs") != 0) { log_debugx("skipping %s, filesystem type is not autofs", mntbuf[i].f_mntonname); continue; } n = node_find(root, mntbuf[i].f_mntonname); if (n != NULL) { log_debugx("leaving autofs mounted on %s", mntbuf[i].f_mntonname); continue; } log_debugx("autofs mounted on %s not found " "in new configuration; unmounting", mntbuf[i].f_mntonname); unmount_by_statfs(&(mntbuf[i]), false); } log_debugx("mounting new autofs mounts"); TAILQ_FOREACH(n, &root->n_children, n_next) { if (!node_is_direct_map(n)) { mount_if_not_already(n, n->n_map, n->n_options, n->n_key, mntbuf, nitems); continue; } TAILQ_FOREACH(n2, &n->n_children, n_next) { mount_if_not_already(n2, n->n_map, n->n_options, rootdir, mntbuf, nitems); } } } static void flush_autofs(const char *fspath) { int error; log_debugx("flushing %s", fspath); error = mount("autofs", fspath, MNT_UPDATE, NULL, 0); if (error != 0) log_err(1, "cannot flush %s", fspath); } static void flush_caches(void) { struct statvfs *mntbuf; int i, nitems; nitems = getmntinfo(&mntbuf, MNT_WAIT); if (nitems <= 0) log_err(1, "getmntinfo"); log_debugx("flushing autofs caches"); for (i = 0; i < nitems; i++) { if (strcmp(mntbuf[i].f_fstypename, "autofs") != 0) { log_debugx("skipping %s, filesystem type is not autofs", mntbuf[i].f_mntonname); continue; } flush_autofs(mntbuf[i].f_mntonname); } } static void unmount_automounted(bool force) { struct statvfs *mntbuf; int i, nitems; nitems = getmntinfo(&mntbuf, MNT_WAIT); if (nitems <= 0) log_err(1, "getmntinfo"); log_debugx("unmounting automounted filesystems"); for (i = 0; i < nitems; i++) { if (strcmp(mntbuf[i].f_fstypename, "autofs") == 0) { log_debugx("skipping %s, filesystem type is autofs", mntbuf[i].f_mntonname); continue; } if ((mntbuf[i].f_flag & MNT_AUTOMOUNTED) == 0) { log_debugx("skipping %s, not automounted", mntbuf[i].f_mntonname); continue; } unmount_by_statfs(&(mntbuf[i]), force); } } __dead static void usage_automount(void) { fprintf(stderr, "Usage: %s [-D name=value][-o opts][-Lcfuv]\n", getprogname()); exit(1); } int main_automount(int argc, char **argv) { struct node *root; int ch, debug = 0, show_maps = 0; char *options = NULL; bool do_unmount = false, force_unmount = false, flush = false; /* * Note that in automount(8), the only purpose of variable * handling is to aid in debugging maps (automount -L). */ defined_init(); while ((ch = getopt(argc, argv, "D:Lfco:uv")) != -1) { switch (ch) { case 'D': defined_parse_and_add(optarg); break; case 'L': show_maps++; break; case 'c': flush = true; break; case 'f': force_unmount = true; break; case 'o': options = concat(options, ',', optarg); break; case 'u': do_unmount = true; break; case 'v': debug++; break; case '?': default: usage_automount(); } } argc -= optind; if (argc != 0) usage_automount(); if (force_unmount && !do_unmount) usage_automount(); log_init(debug); if (flush) { flush_caches(); return 0; } if (do_unmount) { unmount_automounted(force_unmount); return 0; } root = node_new_root(); parse_master(root, AUTO_MASTER_PATH); if (show_maps) { if (show_maps > 1) { node_expand_indirect_maps(root); node_expand_ampersand(root, NULL); } node_expand_defined(root); node_print(root, options); return 0; } mount_unmount(root); return 0; }