/* $NetBSD: statd.c,v 1.32.6.1 2019/08/16 19:25:31 martin Exp $ */ /* * Copyright (c) 1995 * A.R. Gordon (andrew.gordon@net-tel.co.uk). All rights reserved. * * 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 acknowledgement: * This product includes software developed for the FreeBSD project * This product includes software developed by Christos Zoulas. * 4. Neither the name of the author nor the names of any co-contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY ANDREW GORDON 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 #ifndef lint __RCSID("$NetBSD: statd.c,v 1.32.6.1 2019/08/16 19:25:31 martin Exp $"); #endif /* main() function for status monitor daemon. Some of the code in this */ /* file was generated by running rpcgen /usr/include/rpcsvc/sm_inter.x */ /* The actual program logic is in the file procs.c */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "statd.h" struct sigaction sa; int debug = 0; /* Controls syslog() for debug msgs */ extern int _rpcsvcdirty; static DB *db; /* Database file */ Header status_info; static char undefdata[] = "\0\1\2\3\4\5\6\7"; static DBT undefkey = { undefdata, sizeof(undefdata) }; /* statd.c */ static int walk_one(int (*fun )(DBT *, HostInfo *, void *), DBT *, DBT *, void *); static int walk_db(int (*fun )(DBT *, HostInfo *, void *), void *); static int reset_host(DBT *, HostInfo *, void *); static int check_work(DBT *, HostInfo *, void *); static int unmon_host(DBT *, HostInfo *, void *); static int notify_one(DBT *, HostInfo *, void *); static void init_file(const char *); static int notify_one_host(const char *); static void die(int) __dead; int main(int argc, char *argv[]) { int ch; struct sigaction nsa; int maxrec = RPC_MAXDATASIZE; while ((ch = getopt(argc, argv, "d")) != (-1)) { switch (ch) { case 'd': debug = 1; break; default: case '?': (void)fprintf(stderr, "usage: %s [-d]\n", getprogname()); exit(1); /* NOTREACHED */ } } (void)rpcb_unset(SM_PROG, SM_VERS, NULL); rpc_control(RPC_SVC_CONNMAXREC_SET, &maxrec); if (!svc_create(sm_prog_1, SM_PROG, SM_VERS, "udp")) { errx(EXIT_FAILURE, "cannot create udp service."); /* NOTREACHED */ } if (!svc_create(sm_prog_1, SM_PROG, SM_VERS, "tcp")) { errx(EXIT_FAILURE, "cannot create udp service."); /* NOTREACHED */ } init_file("/var/db/statd.status"); /* * Note that it is NOT sensible to run this program from inetd - the * protocol assumes that it will run immediately at boot time. */ if (!debug) daemon(0, 0); sigemptyset(&nsa.sa_mask); nsa.sa_flags = SA_NOCLDSTOP|SA_NOCLDWAIT; nsa.sa_handler = SIG_IGN; (void)sigaction(SIGCHLD, &nsa, NULL); pidfile(NULL); openlog("rpc.statd", 0, LOG_DAEMON); if (debug) syslog(LOG_INFO, "Starting - debug enabled"); else syslog(LOG_INFO, "Starting"); sa.sa_handler = die; sa.sa_flags = 0; sigemptyset(&sa.sa_mask); (void)sigaction(SIGTERM, &sa, NULL); (void)sigaction(SIGQUIT, &sa, NULL); (void)sigaction(SIGHUP, &sa, NULL); (void)sigaction(SIGINT, &sa, NULL); sa.sa_handler = SIG_IGN; sa.sa_flags = SA_RESTART; sigemptyset(&sa.sa_mask); sigaddset(&sa.sa_mask, SIGALRM); /* Initialisation now complete - start operating */ /* Notify hosts that need it */ notify_handler(0); while (1) svc_run(); /* Should never return */ die(0); } /* notify_handler ---------------------------------------------------------- */ /* * Purpose: Catch SIGALRM and collect process status * Returns: Nothing. * Notes: No special action required, other than to collect the * process status and hence allow the child to die: * we only use child processes for asynchronous transmission * of SM_NOTIFY to other systems, so it is normal for the * children to exit when they have done their work. */ void notify_handler(int sig) { time_t now; NO_ALARM; sa.sa_handler = SIG_IGN; (void)sigaction(SIGALRM, &sa, NULL); now = time(NULL); (void) walk_db(notify_one, &now); if (walk_db(check_work, &now) == 0) { /* * No more work to be done. */ CLR_ALARM; return; } sync_file(); ALARM; alarm(5); } /* sync_file --------------------------------------------------------------- */ /* * Purpose: Packaged call of msync() to flush changes to mmap()ed file * Returns: Nothing. Errors to syslog. */ void sync_file() { DBT data; data.data = &status_info; data.size = sizeof(status_info); switch ((*db->put)(db, &undefkey, &data, 0)) { case 0: return; case -1: goto bad; default: abort(); } if ((*db->sync)(db, 0) == -1) { bad: syslog(LOG_ERR, "database corrupted %m"); die(1); } } /* change_host -------------------------------------------------------------- */ /* * Purpose: Update/Create an entry for host * Returns: Nothing * Notes: * */ void change_host(char *hostnamep, HostInfo *hp) { DBT key, data; char *ptr; char hostname[MAXHOSTNAMELEN + 1]; HostInfo h; strncpy(hostname, hostnamep, MAXHOSTNAMELEN + 1); h = *hp; for (ptr = hostname; *ptr; ptr++) if (isupper((unsigned char) *ptr)) *ptr = tolower((unsigned char) *ptr); key.data = hostname; key.size = ptr - hostname + 1; data.data = &h; data.size = sizeof(h); switch ((*db->put)(db, &key, &data, 0)) { case -1: syslog(LOG_ERR, "database corrupted %m"); die(1); case 0: return; default: abort(); } } /* find_host -------------------------------------------------------------- */ /* * Purpose: Find the entry in the status file for a given host * Returns: Copy of entry in hd, or NULL * Notes: * */ HostInfo * find_host(char *hostname, HostInfo *hp) { DBT key, data; char *ptr; for (ptr = hostname; *ptr; ptr++) if (isupper((unsigned char) *ptr)) *ptr = tolower((unsigned char) *ptr); key.data = hostname; key.size = ptr - hostname + 1; switch ((*db->get)(db, &key, &data, 0)) { case 0: if (data.size != sizeof(*hp)) goto bad; return memcpy(hp, data.data, sizeof(*hp)); case 1: return NULL; case -1: goto bad; default: abort(); } bad: syslog(LOG_ERR, "Database corrupted %m"); return NULL; } /* walk_one ------------------------------------------------------------- */ /* * Purpose: Call the given function if the element is valid * Returns: Nothing - exits on error * Notes: */ static int walk_one(int (*fun)(DBT *, HostInfo *, void *), DBT *key, DBT *data, void *ptr) { HostInfo h; if (key->size == undefkey.size && memcmp(key->data, undefkey.data, key->size) == 0) return 0; if (data->size != sizeof(HostInfo)) { syslog(LOG_ERR, "Bad data in database"); die(1); } memcpy(&h, data->data, sizeof(h)); return (*fun)(key, &h, ptr); } /* walk_db -------------------------------------------------------------- */ /* * Purpose: Iterate over all elements calling the given function * Returns: -1 if function failed, 0 on success * Notes: */ static int walk_db(int (*fun)(DBT *, HostInfo *, void *), void *ptr) { DBT key, data; switch ((*db->seq)(db, &key, &data, R_FIRST)) { case -1: goto bad; case 1: /* We should have at least the magic entry at this point */ abort(); case 0: if (walk_one(fun, &key, &data, ptr) == -1) return -1; break; default: abort(); } for (;;) switch ((*db->seq)(db, &key, &data, R_NEXT)) { case -1: goto bad; case 0: if (walk_one(fun, &key, &data, ptr) == -1) return -1; break; case 1: return 0; default: abort(); } bad: syslog(LOG_ERR, "Corrupted database %m"); die(1); } /* reset_host ------------------------------------------------------------ */ /* * Purpose: Clean up existing hosts in file. * Returns: Always success 0. * Notes: Clean-up of existing file - monitored hosts will have a * pointer to a list of clients, which refers to memory in * the previous incarnation of the program and so are * meaningless now. These pointers are zeroed and the fact * that the host was previously monitored is recorded by * setting the notifyReqd flag, which will in due course * cause a SM_NOTIFY to be sent. * * Note that if we crash twice in quick succession, some hosts * may already have notifyReqd set, where we didn't manage to * notify them before the second crash occurred. */ static int reset_host(DBT *key, HostInfo *hi, void *ptr) { if (hi->monList) { hi->notifyReqd = *(time_t *) ptr; hi->attempts = 0; hi->monList = NULL; change_host((char *)key->data, hi); } return 0; } /* check_work ------------------------------------------------------------ */ /* * Purpose: Check if there is work to be done. * Returns: 0 if there is no work to be done -1 if there is. * Notes: */ static int check_work(DBT *key, HostInfo *hi, void *ptr) { return hi->notifyReqd ? -1 : 0; } /* unmon_host ------------------------------------------------------------ */ /* * Purpose: Unmonitor a host * Returns: 0 * Notes: */ static int unmon_host(DBT *key, HostInfo *hi, void *ptr) { char *name = key->data; if (do_unmon(name, hi, ptr)) change_host(name, hi); return 0; } /* notify_one ------------------------------------------------------------ */ /* * Purpose: Notify one host. * Returns: 0 if success -1 on failure * Notes: */ static int notify_one(DBT *key, HostInfo *hi, void *ptr) { time_t now = *(time_t *) ptr; char *name = key->data; int error; if (hi->notifyReqd == 0 || hi->notifyReqd > now) return 0; /* * If one of the initial attempts fails, we wait * for a while and have another go. This is necessary * because when we have crashed, (eg. a power outage) * it is quite possible that we won't be able to * contact all monitored hosts immediately on restart, * either because they crashed too and take longer * to come up (in which case the notification isn't * really required), or more importantly if some * router etc. needed to reach the monitored host * has not come back up yet. In this case, we will * be a bit late in re-establishing locks (after the * grace period) but that is the best we can do. We * try 10 times at 5 sec intervals, 10 more times at * 1 minute intervals, then 24 more times at hourly * intervals, finally giving up altogether if the * host hasn't come back to life after 24 hours. */ if (notify_one_host(name) || hi->attempts++ >= 44) { error = 0; hi->notifyReqd = 0; hi->attempts = 0; } else { error = -1; if (hi->attempts < 10) hi->notifyReqd += 5; else if (hi->attempts < 20) hi->notifyReqd += 60; else hi->notifyReqd += 60 * 60; } change_host(name, hi); return error; } /* init_file -------------------------------------------------------------- */ /* * Purpose: Open file, create if necessary, initialise it. * Returns: Nothing - exits on error * Notes: Called before process becomes daemon, hence logs to * stderr rather than syslog. * Opens the file, then mmap()s it for ease of access. * Also performs initial clean-up of the file, zeroing * monitor list pointers, setting the notifyReqd flag in * all hosts that had a monitor list, and incrementing * the state number to the next even value. */ static void init_file(const char *filename) { DBT data; db = dbopen(filename, O_RDWR|O_CREAT|O_NDELAY|O_EXLOCK, 0644, DB_HASH, NULL); if (db == NULL) err(EXIT_FAILURE, "Cannot open `%s'", filename); switch ((*db->get)(db, &undefkey, &data, 0)) { case 1: /* New database */ (void)memset(&status_info, 0, sizeof(status_info)); sync_file(); return; case -1: err(EXIT_FAILURE, "error accessing database (%s)", strerror(errno)); case 0: /* Existing database */ if (data.size != sizeof(status_info)) errx(EXIT_FAILURE, "database corrupted %lu != %lu", (u_long)data.size, (u_long)sizeof(status_info)); memcpy(&status_info, data.data, data.size); break; default: abort(); } reset_database(); return; } /* reset_database --------------------------------------------------------- */ /* * Purpose: Clears the statd database * Returns: Nothing * Notes: If this is not called on reset, it will leak memory. */ void reset_database() { time_t now = time(NULL); walk_db(reset_host, &now); /* Select the next higher even number for the state counter */ status_info.ourState = (status_info.ourState + 2) & 0xfffffffe; status_info.ourState++; /* XXX - ??? */ sync_file(); } /* unmon_hosts --------------------------------------------------------- */ /* * Purpose: Unmonitor all the hosts * Returns: Nothing * Notes: */ void unmon_hosts() { time_t now = time(NULL); walk_db(unmon_host, &now); sync_file(); } static int notify_one_host(const char *hostname) { struct timeval timeout = {20, 0}; /* 20 secs timeout */ CLIENT *cli; char dummy; stat_chge arg; char our_hostname[MAXHOSTNAMELEN + 1]; gethostname(our_hostname, sizeof(our_hostname)); our_hostname[sizeof(our_hostname) - 1] = '\0'; arg.mon_name = our_hostname; arg.state = status_info.ourState; if (debug) syslog(LOG_DEBUG, "Sending SM_NOTIFY to host %s from %s", hostname, our_hostname); cli = clnt_create(hostname, SM_PROG, SM_VERS, "udp"); if (!cli) { syslog(LOG_ERR, "Failed to contact host %s%s", hostname, clnt_spcreateerror("")); return (FALSE); } if (clnt_call(cli, SM_NOTIFY, xdr_stat_chge, &arg, xdr_void, &dummy, timeout) != RPC_SUCCESS) { syslog(LOG_ERR, "Failed to contact rpc.statd at host %s", hostname); clnt_destroy(cli); return (FALSE); } clnt_destroy(cli); return (TRUE); } static void die(int n) { (*db->close)(db); exit(n); }