/* $OpenBSD: mount_portal.c,v 1.29 2009/10/27 23:59:33 deraadt Exp $ */ /* $NetBSD: mount_portal.c,v 1.8 1996/04/13 01:31:54 jtc Exp $ */ /* * Copyright (c) 1992, 1993, 1994 * The Regents of the University of California. All rights reserved. * * This code is derived from software donated to Berkeley by * Jan-Simon Pendry. * * 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. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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 #include #include #include #include #include #include #include #include #include #include #include #include #include "mntopts.h" #include "pathnames.h" #include "portald.h" const struct mntopt mopts[] = { MOPT_STDOPTS, { NULL } }; extern char *__progname; /* from crt0.o */ static char mountpt[MAXPATHLEN]; /* made available to signal handler */ static void usage(void); static volatile sig_atomic_t readcf; /* Set when SIGHUP received */ static void sigchld(int sig) { int save_errno = errno; struct syslog_data sdata = SYSLOG_DATA_INIT; pid_t pid; while ((pid = waitpid((pid_t) -1, NULL, WNOHANG)) > 0) ; if (pid < 0 && errno != ECHILD) syslog_r(LOG_WARNING, &sdata, "waitpid: %m"); errno = save_errno; } static void sighup(int sig) { readcf = 1; } static void sigterm(int sig) { struct syslog_data sdata = SYSLOG_DATA_INIT; if (unmount(mountpt, MNT_FORCE) < 0) syslog_r(LOG_WARNING, &sdata, "sigterm: unmounting %s failed: %m", mountpt); _exit(1); } int main(int argc, char *argv[]) { struct portal_args args; struct sockaddr_un un; char *conf; int mntflags = 0; char tag[32]; fd_set *fdsp; int fdssize; qelem q; int so; int error = 0; /* * Crack command line args */ int ch; while ((ch = getopt(argc, argv, "o:")) != -1) { switch (ch) { case 'o': getmntopts(optarg, mopts, &mntflags); break; default: error = 1; break; } } if (optind != (argc - 2)) error = 1; if (error) usage(); /* * Get config file and mount point */ conf = argv[optind]; if (realpath(argv[optind+1], mountpt) == NULL) err(1, "realpath %s", argv[optind+1]); /* * Construct the listening socket */ un.sun_family = AF_UNIX; if (sizeof(_PATH_TMPPORTAL) >= sizeof(un.sun_path)) errx(1, "portal socket name too long"); (void)strlcpy(un.sun_path, _PATH_TMPPORTAL, sizeof un.sun_path); so = mkstemp(un.sun_path); if (so < 0) err(1, "can't create portal socket name: %s", un.sun_path); un.sun_len = strlen(un.sun_path); (void)close(so); so = socket(AF_UNIX, SOCK_STREAM, 0); if (so < 0) err(1, "socket(2)"); (void)unlink(un.sun_path); /* XXX teeny race? */ if (bind(so, (struct sockaddr *) &un, sizeof(un)) < 0) err(1, "bind(2)"); (void)listen(so, 5); args.pa_socket = so; /* * Must fork before mount to get pid in name right. */ daemon(0, 0); (void)snprintf(tag, sizeof(tag), "portal:%ld", (long)getpid()); args.pa_config = tag; /* * Start logging (and change name) */ openlog("portald", LOG_CONS|LOG_PID, LOG_DAEMON); if (mount(MOUNT_PORTAL, mountpt, mntflags, &args)) { if (errno == EOPNOTSUPP) syslog(LOG_ERR, "mount: Filesystem not supported by kernel"); else syslog(LOG_ERR, "mount: %m"); exit(1); } q.q_forw = q.q_back = &q; readcf = 1; (void)signal(SIGCHLD, sigchld); (void)signal(SIGHUP, sighup); (void)signal(SIGTERM, sigterm); fdssize = howmany(so+1, NFDBITS) * sizeof(fd_mask); fdsp = (fd_set *)malloc(fdssize); if (fdsp == NULL) err(1, "malloc"); /* * Just loop waiting for new connections and activating them */ for (;;) { struct sockaddr_un un2; socklen_t salen = sizeof(un2); int so2; pid_t pid; int rc; /* * Check whether we need to re-read the configuration file */ if (readcf) { readcf = 0; conf_read(&q, conf); continue; } /* * Accept a new connection * Will get EINTR if a signal has arrived, so just * ignore that error code */ memset(fdsp, 0, fdssize); FD_SET(so, fdsp); rc = select(so+1, fdsp, NULL, NULL, NULL); if (rc < 0) { if (errno == EINTR) continue; syslog(LOG_ERR, "select: %m"); exit(1); } if (rc == 0) break; so2 = accept(so, (struct sockaddr *) &un2, &salen); if (so2 < 0) { /* * The unmount function does a shutdown on the socket * which will generated ECONNABORTED on the accept. */ if (errno == ECONNABORTED) break; if (errno != EINTR) { syslog(LOG_ERR, "accept: %m"); exit(1); } continue; } /* * Now fork a new child to deal with the connection */ eagain:; switch (pid = fork()) { case -1: if (errno == EAGAIN) { sleep(1); goto eagain; } syslog(LOG_ERR, "fork: %m"); break; case 0: (void)close(so); activate(&q, so2); exit(0); default: (void)close(so2); break; } } free(fdsp); syslog(LOG_INFO, "%s unmounted", mountpt); exit(0); } static void usage(void) { (void)fprintf(stderr, "usage: %s [-o options] config mount_point\n", __progname); exit(1); }