NetBSD/dist/am-utils/amd/amd.c

623 lines
16 KiB
C

/* $NetBSD: amd.c,v 1.8 2005/04/23 18:38:17 christos Exp $ */
/*
* Copyright (c) 1997-2005 Erez Zadok
* Copyright (c) 1989 Jan-Simon Pendry
* Copyright (c) 1989 Imperial College of Science, Technology & Medicine
* Copyright (c) 1989 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Jan-Simon Pendry at Imperial College, London.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgment:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*
*
* Id: amd.c,v 1.35 2005/03/08 06:05:33 ezk Exp
*
*/
/*
* Automounter
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif /* HAVE_CONFIG_H */
#include <am_defs.h>
#include <amd.h>
struct amu_global_options gopt; /* where global options are stored */
char pid_fsname[16 + MAXHOSTNAMELEN]; /* "kiska.southseas.nz:(pid%d)" */
char *hostdomain = "unknown.domain";
char hostd[2 * MAXHOSTNAMELEN + 1]; /* Host+domain */
char *endian = ARCH_ENDIAN; /* Big or Little endian */
char *cpu = HOST_CPU; /* CPU type */
char *PrimNetName; /* name of primary network */
char *PrimNetNum; /* number of primary network */
int immediate_abort; /* Should close-down unmounts be retried */
int orig_umask = 022;
int select_intr_valid;
jmp_buf select_intr;
struct amd_stats amd_stats; /* Server statistics */
struct in_addr myipaddr; /* (An) IP address of this host */
time_t do_mapc_reload = 0; /* mapc_reload() call required? */
#ifdef HAVE_FS_AUTOFS
int amd_use_autofs = 0;
#endif /* HAVE_FS_AUTOFS */
#ifdef HAVE_SIGACTION
sigset_t masked_sigs;
#endif /* HAVE_SIGACTION */
/*
* Signal handler:
* SIGINT - tells amd to do a full shutdown, including unmounting all
* filesystem.
* SIGTERM - tells amd to shutdown now. Just unmounts the automount nodes.
*/
static RETSIGTYPE
sigterm(int sig)
{
#ifdef REINSTALL_SIGNAL_HANDLER
signal(sig, sigterm);
#endif /* REINSTALL_SIGNAL_HANDLER */
switch (sig) {
case SIGINT:
immediate_abort = 15;
break;
case SIGTERM:
immediate_abort = -1;
/* fall through... */
default:
plog(XLOG_WARNING, "WARNING: automounter going down on signal %d", sig);
break;
}
if (select_intr_valid)
longjmp(select_intr, sig);
}
/*
* Hook for cache reload.
* When a SIGHUP arrives it schedules a call to mapc_reload
*/
static RETSIGTYPE
sighup(int sig)
{
#ifdef REINSTALL_SIGNAL_HANDLER
signal(sig, sighup);
#endif /* REINSTALL_SIGNAL_HANDLER */
if (sig != SIGHUP)
dlog("spurious call to sighup");
/*
* Force a reload by zero'ing the timer
*/
if (amd_state == Run)
do_mapc_reload = 0;
}
static RETSIGTYPE
parent_exit(int sig)
{
/*
* This signal handler is called during Amd initialization. The parent
* forks a child to do all the hard automounting work, and waits for a
* SIGQUIT signal from the child. When the parent gets the signal it's
* supposed to call this handler and exit(3), thus completing the
* daemonizing process. Alas, on some systems, especially Linux 2.4/2.6
* with Glibc, exit(3) doesn't always terminate the parent process.
* Worse, the parent process now refuses to accept any more SIGQUIT
* signals -- they are blocked. What's really annoying is that this
* doesn't happen all the time, suggesting a race condition somewhere.
* (This happens even if I change the logic to use another signal.) I
* traced this to something which exit(3) does in addition to exiting the
* process, probably some atexit() stuff or other side-effects related to
* signal handling. Either way, since at this stage the parent process
* just needs to terminate, I'm simply calling _exit(2). Note also that
* the OpenGroup doesn't list exit(3) as a recommended "Base Interface"
* but they do list _exit(2) as one. This fix seems to work reliably all
* the time. -Erez (2/27/2005)
*/
_exit(0);
}
static int
daemon_mode(void)
{
int bgpid;
#ifdef HAVE_SIGACTION
struct sigaction sa, osa;
memset(&sa, 0, sizeof(sa));
sa.sa_handler = parent_exit;
sa.sa_flags = 0;
sigemptyset(&(sa.sa_mask));
sigaddset(&(sa.sa_mask), SIGQUIT);
sigaction(SIGQUIT, &sa, &osa);
#else /* not HAVE_SIGACTION */
signal(SIGQUIT, parent_exit);
#endif /* not HAVE_SIGACTION */
bgpid = background();
if (bgpid != 0) {
/*
* Now wait for the automount points to
* complete.
*/
for (;;)
pause();
/* should never reach here */
}
#ifdef HAVE_SIGACTION
sigaction(SIGQUIT, &osa, NULL);
#else /* not HAVE_SIGACTION */
signal(SIGQUIT, SIG_DFL);
#endif /* not HAVE_SIGACTION */
/*
* Record our pid to make it easier to kill the correct amd.
*/
if (gopt.flags & CFM_PRINT_PID) {
if (STREQ(gopt.pid_file, "/dev/stdout")) {
printf("%ld\n", (long) am_mypid);
/* flush stdout, just in case */
fflush(stdout);
} else {
FILE *f;
mode_t prev_umask = umask(0022); /* set secure temporary umask */
f = fopen(gopt.pid_file, "w");
if (f) {
fprintf(f, "%ld\n", (long) am_mypid);
(void) fclose(f);
} else {
fprintf(stderr, "cannot open %s (errno=%d)\n", gopt.pid_file, errno);
}
umask(prev_umask); /* restore umask */
}
}
/*
* Pretend we are in the foreground again
*/
foreground = 1;
/*
* Dissociate from the controlling terminal
*/
amu_release_controlling_tty();
return getppid();
}
/*
* Initialize global options structure.
*/
static void
init_global_options(void)
{
#if defined(HAVE_SYS_UTSNAME_H) && defined(HAVE_UNAME)
static struct utsname un;
#endif /* defined(HAVE_SYS_UTSNAME_H) && defined(HAVE_UNAME) */
int i;
memset(&gopt, 0, sizeof(struct amu_global_options));
/* name of current architecture */
gopt.arch = HOST_ARCH;
/* automounter temp dir */
gopt.auto_dir = "/a";
/* toplevel attribute cache timeout */
gopt.auto_attrcache = 0;
/* cluster name */
gopt.cluster = NULL;
/* executable map timeout */
gopt.exec_map_timeout = AMFS_EXEC_MAP_TIMEOUT;
/*
* kernel architecture: this you must get from uname() if possible.
*/
#if defined(HAVE_SYS_UTSNAME_H) && defined(HAVE_UNAME)
if (uname(&un) >= 0)
gopt.karch = un.machine;
else
#endif /* defined(HAVE_SYS_UTSNAME_H) && defined(HAVE_UNAME) */
gopt.karch = HOST_ARCH;
/* amd log file */
gopt.logfile = NULL;
/* operating system name */
gopt.op_sys = HOST_OS_NAME;
/* OS version */
gopt.op_sys_ver = HOST_OS_VERSION;
/* full OS name and version */
gopt.op_sys_full = HOST_OS;
/* OS version */
gopt.op_sys_vendor = HOST_VENDOR;
/* pid file */
gopt.pid_file = "/dev/stdout";
/* local domain */
gopt.sub_domain = NULL;
/* reset NFS retransmit counter and retry interval */
for (i=0; i<AMU_TYPE_MAX; ++i) {
gopt.amfs_auto_retrans[i] = -1;
gopt.amfs_auto_timeo[i] = -1;
}
/* cache duration */
gopt.am_timeo = AM_TTL;
/* dismount interval */
gopt.am_timeo_w = AM_TTL_W;
/* map reload intervl */
gopt.map_reload_interval = ONE_HOUR;
/*
* various CFM_* flags that are on by default.
*/
gopt.flags = CFM_DEFAULT_FLAGS;
#ifdef HAVE_MAP_HESIOD
/* Hesiod rhs zone */
gopt.hesiod_base = "automount";
#endif /* HAVE_MAP_HESIOD */
#ifdef HAVE_MAP_LDAP
/* LDAP base */
gopt.ldap_base = NULL;
/* LDAP host ports */
gopt.ldap_hostports = NULL;
/* LDAP cache */
gopt.ldap_cache_seconds = 0;
gopt.ldap_cache_maxmem = 131072;
/* LDAP protocol version */
gopt.ldap_proto_version = 2;
#endif /* HAVE_MAP_LDAP */
#ifdef HAVE_MAP_NIS
/* YP domain name */
gopt.nis_domain = NULL;
#endif /* HAVE_MAP_NIS */
}
/*
* Lock process text and data segment in memory (after forking the daemon)
*/
static void
do_memory_locking(void)
{
#if defined(HAVE_PLOCK) || defined(HAVE_MLOCKALL)
int locked_ok = 0;
#else /* not HAVE_PLOCK and not HAVE_MLOCKALL */
plog(XLOG_WARNING, "Process memory locking not supported by the OS");
#endif /* not HAVE_PLOCK and not HAVE_MLOCKALL */
#ifdef HAVE_PLOCK
# ifdef _AIX
/*
* On AIX you must lower the stack size using ulimit() before calling
* plock. Otherwise plock will reserve a lot of memory space based on
* your maximum stack size limit. Since it is not easily possible to
* tell what should the limit be, I print a warning before calling
* plock(). See the manual pages for ulimit(1,3,4) on your AIX system.
*/
plog(XLOG_WARNING, "AIX: may need to lower stack size using ulimit(3) before calling plock");
# endif /* _AIX */
if (!locked_ok && plock(PROCLOCK) != 0)
plog(XLOG_WARNING, "Couldn't lock process pages in memory using plock(): %m");
else
locked_ok = 1;
#endif /* HAVE_PLOCK */
#ifdef HAVE_MLOCKALL
if (!locked_ok && mlockall(MCL_CURRENT|MCL_FUTURE) != 0)
plog(XLOG_WARNING, "Couldn't lock process pages in memory using mlockall(): %m");
else
locked_ok = 1;
#endif /* HAVE_MLOCKALL */
#if defined(HAVE_PLOCK) || defined(HAVE_MLOCKALL)
if (locked_ok)
plog(XLOG_INFO, "Locked process pages in memory");
#endif /* HAVE_PLOCK || HAVE_MLOCKALL */
#if defined(HAVE_MADVISE) && defined(MADV_PROTECT)
madvise(0, 0, MADV_PROTECT); /* may be redundant of the above worked out */
#endif /* defined(HAVE_MADVISE) && defined(MADV_PROTECT) */
}
int
main(int argc, char *argv[])
{
char *domdot, *verstr;
int ppid = 0;
int error;
char *progname = NULL; /* "amd" */
char hostname[MAXHOSTNAMELEN + 1] = "localhost"; /* Hostname */
#ifdef HAVE_SIGACTION
struct sigaction sa;
#endif /* HAVE_SIGACTION */
/*
* Make sure some built-in assumptions are true before we start
*/
assert(sizeof(nfscookie) >= sizeof(u_int));
assert(sizeof(int) >= 4);
/*
* Set processing status.
*/
amd_state = Start;
/*
* Determine program name
*/
if (argv[0]) {
progname = strrchr(argv[0], '/');
if (progname && progname[1])
progname++;
else
progname = argv[0];
}
if (!progname)
progname = "amd";
am_set_progname(progname);
/*
* Initialize process id. This is kept
* cached since it is used for generating
* and using file handles.
*/
am_set_mypid();
/*
* Get local machine name
*/
if (gethostname(hostname, sizeof(hostname)) < 0) {
plog(XLOG_FATAL, "gethostname: %m");
going_down(1);
}
hostname[sizeof(hostname) - 1] = '\0';
/*
* Check it makes sense
*/
if (!*hostname) {
plog(XLOG_FATAL, "host name is not set");
going_down(1);
}
/*
* Initialize global options structure.
*/
init_global_options();
/*
* Partially initialize hostd[]. This
* is completed in get_args().
*/
if ((domdot = strchr(hostname, '.'))) {
/*
* Hostname already contains domainname.
* Split out hostname and domainname
* components
*/
*domdot++ = '\0';
hostdomain = domdot;
}
strlcpy(hostd, hostname, sizeof(hostd));
am_set_hostname(hostname);
/*
* Trap interrupts for shutdowns.
*/
#ifdef HAVE_SIGACTION
memset(&sa, 0, sizeof(sa));
sa.sa_handler = sigterm;
sa.sa_flags = 0;
sigemptyset(&(sa.sa_mask));
sigaddset(&(sa.sa_mask), SIGINT);
sigaddset(&(sa.sa_mask), SIGTERM);
sigaction(SIGINT, &sa, NULL);
sigaction(SIGTERM, &sa, NULL);
#else /* not HAVE_SIGACTION */
(void) signal(SIGINT, sigterm);
#endif /* not HAVE_SIGACTION */
/*
* Trap Terminate so that we can shutdown gracefully (some chance)
*/
#ifdef HAVE_SIGACTION
sa.sa_handler = sigterm;
sa.sa_flags = 0;
sigemptyset(&(sa.sa_mask));
sigaddset(&(sa.sa_mask), SIGTERM);
sigaction(SIGTERM, &sa, NULL);
#else /* not HAVE_SIGACTION */
(void) signal(SIGTERM, sigterm);
#endif /* not HAVE_SIGACTION */
/*
* Hangups tell us to reload the cache
*/
#ifdef HAVE_SIGACTION
sa.sa_handler = sighup;
sa.sa_flags = 0;
sigemptyset(&(sa.sa_mask));
sigaddset(&(sa.sa_mask), SIGHUP);
sigaction(SIGHUP, &sa, NULL);
#else /* not HAVE_SIGACTION */
(void) signal(SIGHUP, sighup);
#endif /* not HAVE_SIGACTION */
/*
* Trap Death-of-a-child. These allow us to
* pick up the exit status of backgrounded mounts.
* See "sched.c".
*/
#ifdef HAVE_SIGACTION
sa.sa_handler = sigchld;
sa.sa_flags = 0;
sigemptyset(&(sa.sa_mask));
sigaddset(&(sa.sa_mask), SIGCHLD);
sigaction(SIGCHLD, &sa, NULL);
/*
* construct global "masked_sigs" used in nfs_start.c
*/
sigemptyset(&masked_sigs);
sigaddset(&masked_sigs, SIGHUP);
sigaddset(&masked_sigs, SIGCHLD);
sigaddset(&masked_sigs, SIGTERM);
sigaddset(&masked_sigs, SIGINT);
#else /* not HAVE_SIGACTION */
(void) signal(SIGCHLD, sigchld);
#endif /* not HAVE_SIGACTION */
/*
* Fix-up any umask problems. Most systems default
* to 002 which is not too convenient for our purposes
*/
orig_umask = umask(0);
/*
* Figure out primary network name
*/
getwire(&PrimNetName, &PrimNetNum);
/*
* Determine command-line arguments
*/
get_args(argc, argv);
/*
* Log version information.
*/
verstr = strtok(get_version_string(), "\n");
plog(XLOG_INFO, "AM-UTILS VERSION INFORMATION:");
while (verstr) {
plog(XLOG_INFO, "%s", verstr);
verstr = strtok(NULL, "\n");
}
/*
* Get our own IP address so that we can mount the automounter. We pass
* localhost_address which could be used as the default localhost
* name/address in amu_get_myaddress().
*/
amu_get_myaddress(&myipaddr, gopt.localhost_address);
plog(XLOG_INFO, "My ip addr is %s", inet_ntoa(myipaddr));
/* avoid hanging on other NFS servers if started elsewhere */
if (chdir("/") < 0)
plog(XLOG_INFO, "cannot chdir to /: %m");
/*
* Now check we are root.
*/
if (geteuid() != 0) {
plog(XLOG_FATAL, "Must be root to mount filesystems (euid = %ld)", (long) geteuid());
going_down(1);
}
#ifdef HAVE_MAP_NIS
/*
* If the domain was specified then bind it here
* to circumvent any default bindings that may
* be done in the C library.
*/
if (gopt.nis_domain && yp_bind(gopt.nis_domain)) {
plog(XLOG_FATAL, "Can't bind to NIS domain \"%s\"", gopt.nis_domain);
going_down(1);
}
#endif /* HAVE_MAP_NIS */
if (!amuDebug(D_DAEMON))
ppid = daemon_mode();
/*
* Lock process text and data segment in memory.
*/
if (gopt.flags & CFM_PROCESS_LOCK) {
do_memory_locking();
}
do_mapc_reload = clocktime() + gopt.map_reload_interval;
/*
* Register automounter with system.
*/
error = mount_automounter(ppid);
if (error && ppid)
kill(ppid, SIGALRM);
#ifdef HAVE_FS_AUTOFS
/*
* XXX this should be part of going_down(), but I can't move it there
* because it would be calling non-library code from the library... ugh
*/
if (amd_use_autofs)
destroy_autofs_service();
#endif /* HAVE_FS_AUTOFS */
going_down(error);
abort();
return 1; /* should never get here */
}