/* $NetBSD: autounmountd.c,v 1.2 2019/11/21 16:45:05 tkusumi 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: autounmountd.c,v 1.2 2019/11/21 16:45:05 tkusumi Exp $"); #include #include #include #include #include #include #include #include #include #include #include #include #include "common.h" struct automounted_fs { TAILQ_ENTRY(automounted_fs) af_next; time_t af_mount_time; bool af_mark; fsid_t af_fsid; char af_mountpoint[MNAMELEN]; }; static TAILQ_HEAD(, automounted_fs) automounted; static struct automounted_fs * automounted_find(fsid_t fsid) { struct automounted_fs *af; TAILQ_FOREACH(af, &automounted, af_next) { if (af->af_fsid.__fsid_val[0] == fsid.__fsid_val[0] && af->af_fsid.__fsid_val[1] == fsid.__fsid_val[1]) return af; } return NULL; } static struct automounted_fs * automounted_add(fsid_t fsid, const char *mountpoint) { struct automounted_fs *af; af = calloc(1, sizeof(*af)); if (af == NULL) log_err(1, "calloc"); af->af_mount_time = time(NULL); af->af_fsid = fsid; strlcpy(af->af_mountpoint, mountpoint, sizeof(af->af_mountpoint)); TAILQ_INSERT_TAIL(&automounted, af, af_next); return af; } static void automounted_remove(struct automounted_fs *af) { TAILQ_REMOVE(&automounted, af, af_next); free(af); } static void refresh_automounted(void) { struct automounted_fs *af, *tmpaf; struct statvfs *mntbuf; int i, nitems; nitems = getmntinfo(&mntbuf, MNT_WAIT); if (nitems <= 0) log_err(1, "getmntinfo"); log_debugx("refreshing list of automounted filesystems"); TAILQ_FOREACH(af, &automounted, af_next) af->af_mark = false; 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; } af = automounted_find(mntbuf[i].f_fsidx); if (af == NULL) { log_debugx("new automounted filesystem found on %s " "(FSID:%d:%d)", mntbuf[i].f_mntonname, mntbuf[i].f_fsidx.__fsid_val[0], mntbuf[i].f_fsidx.__fsid_val[1]); af = automounted_add(mntbuf[i].f_fsidx, mntbuf[i].f_mntonname); } else { log_debugx("already known automounted filesystem " "found on %s (FSID:%d:%d)", mntbuf[i].f_mntonname, mntbuf[i].f_fsidx.__fsid_val[0], mntbuf[i].f_fsidx.__fsid_val[1]); } af->af_mark = true; } TAILQ_FOREACH_SAFE(af, &automounted, af_next, tmpaf) { if (af->af_mark) continue; log_debugx("lost filesystem mounted on %s (FSID:%d:%d)", af->af_mountpoint, af->af_fsid.__fsid_val[0], af->af_fsid.__fsid_val[1]); automounted_remove(af); } } static int do_unmount(const fsid_t fsid __unused, const char *mountpoint) { int error; error = unmount(mountpoint, 0); if (error != 0) { if (errno == EBUSY) { log_debugx("cannot unmount %s: %s", mountpoint, strerror(errno)); } else { log_warn("cannot unmount %s", mountpoint); } } return error; } static time_t expire_automounted(time_t expiration_time) { struct automounted_fs *af, *tmpaf; time_t now; time_t mounted_for, mounted_max = -1; int error; now = time(NULL); log_debugx("expiring automounted filesystems"); TAILQ_FOREACH_SAFE(af, &automounted, af_next, tmpaf) { mounted_for = (time_t)difftime(now, af->af_mount_time); if (mounted_for < expiration_time) { log_debugx("skipping %s (FSID:%d:%d), mounted " "for %jd seconds", af->af_mountpoint, af->af_fsid.__fsid_val[0], af->af_fsid.__fsid_val[1], (intmax_t)mounted_for); if (mounted_for > mounted_max) mounted_max = mounted_for; continue; } log_debugx("filesystem mounted on %s (FSID:%d:%d), " "was mounted for %jd seconds; unmounting", af->af_mountpoint, af->af_fsid.__fsid_val[0], af->af_fsid.__fsid_val[1], (intmax_t)mounted_for); error = do_unmount(af->af_fsid, af->af_mountpoint); if (error != 0) { if (mounted_for > mounted_max) mounted_max = mounted_for; } } return mounted_max; } __dead static void usage_autounmountd(void) { fprintf(stderr, "Usage: %s [-r time][-t time][-dv]\n", getprogname()); exit(1); } static void do_wait(int kq, time_t sleep_time) { struct timespec timeout; struct kevent unused; int nevents; if (sleep_time != -1) { assert(sleep_time > 0); timeout.tv_sec = (int)sleep_time; timeout.tv_nsec = 0; log_debugx("waiting for filesystem event for %jd seconds", (intmax_t)sleep_time); nevents = kevent(kq, NULL, 0, &unused, 1, &timeout); } else { log_debugx("waiting for filesystem event"); nevents = kevent(kq, NULL, 0, &unused, 1, NULL); } if (nevents < 0) { if (errno == EINTR) return; log_err(1, "kevent"); } if (nevents == 0) { log_debugx("timeout reached"); assert(sleep_time > 0); } else { log_debugx("got filesystem event"); } } int main_autounmountd(int argc, char **argv) { struct kevent event; int ch, debug = 0, error, kq; time_t expiration_time = 600, retry_time = 600, mounted_max, sleep_time; bool dont_daemonize = false; while ((ch = getopt(argc, argv, "dr:t:v")) != -1) { switch (ch) { case 'd': dont_daemonize = true; debug++; break; case 'r': retry_time = atoi(optarg); break; case 't': expiration_time = atoi(optarg); break; case 'v': debug++; break; case '?': default: usage_autounmountd(); } } argc -= optind; if (argc != 0) usage_autounmountd(); if (retry_time <= 0) log_errx(1, "retry time must be greater than zero"); if (expiration_time <= 0) log_errx(1, "expiration time must be greater than zero"); log_init(debug); if (dont_daemonize == false) { if (daemon(0, 0) == -1) { log_warn("cannot daemonize"); pidfile_clean(); exit(1); } } /* * Call pidfile(3) after daemon(3). */ if (pidfile(NULL) == -1) { if (errno == EEXIST) log_errx(1, "daemon already running"); else if (errno == ENAMETOOLONG) log_errx(1, "pidfile name too long"); log_err(1, "cannot create pidfile"); } if (pidfile_lock(NULL) == -1) log_err(1, "cannot lock pidfile"); TAILQ_INIT(&automounted); kq = kqueue(); if (kq < 0) log_err(1, "kqueue"); EV_SET(&event, 0, EVFILT_FS, EV_ADD | EV_CLEAR, 0, 0, (intptr_t)NULL); error = kevent(kq, &event, 1, NULL, 0, NULL); if (error < 0) log_err(1, "kevent"); for (;;) { refresh_automounted(); mounted_max = expire_automounted(expiration_time); if (mounted_max == -1) { sleep_time = mounted_max; log_debugx("no filesystems to expire"); } else if (mounted_max < expiration_time) { sleep_time = (time_t)difftime(expiration_time, mounted_max); log_debugx("some filesystems expire in %jd seconds", (intmax_t)sleep_time); } else { sleep_time = retry_time; log_debugx("some expired filesystems remain mounted, " "will retry in %jd seconds", (intmax_t)sleep_time); } do_wait(kq, sleep_time); } return 0; }