2 * Send NSM notify calls to all hosts listed in /var/lib/sm
4 * Copyright (C) 2004-2006 Olaf Kirch <okir@suse.de>
8 #include <sys/socket.h>
11 #include <sys/param.h>
12 #include <sys/syslog.h>
13 #include <arpa/inet.h>
29 # define BASEDIR NFS_STATEDIR
31 # define BASEDIR "/var/lib/nfs"
35 #define DEFAULT_SM_STATE_PATH BASEDIR "/state"
36 #define DEFAULT_SM_DIR_PATH BASEDIR "/sm"
37 #define DEFAULT_SM_BAK_PATH DEFAULT_SM_DIR_PATH ".bak"
39 char *_SM_BASE_PATH = BASEDIR;
40 char *_SM_STATE_PATH = DEFAULT_SM_STATE_PATH;
41 char *_SM_DIR_PATH = DEFAULT_SM_DIR_PATH;
42 char *_SM_BAK_PATH = DEFAULT_SM_BAK_PATH;
44 #define NSM_PROG 100024
45 #define NSM_PROGRAM 100024
49 #define NSM_MAX_TIMEOUT 120 /* don't make this too big */
50 #define MAXMSGSIZE 256
52 typedef struct sockaddr_storage nsm_address;
55 struct nsm_host * next;
67 static char nsm_hostname[256];
68 static uint32_t nsm_state;
69 static int opt_debug = 0;
70 static int opt_quiet = 0;
71 static int opt_update_state = 1;
72 static unsigned int opt_max_retry = 15 * 60;
73 static char * opt_srcaddr = 0;
74 static uint16_t opt_srcport = 0;
75 static int log_syslog = 0;
77 static unsigned int nsm_get_state(int);
78 static void notify(void);
79 static void notify_host(int, struct nsm_host *);
80 static void recv_reply(int);
81 static void backup_hosts(const char *, const char *);
82 static void get_hosts(const char *);
83 static void insert_host(struct nsm_host *);
84 struct nsm_host * find_host(uint32_t);
85 static int addr_get_port(nsm_address *);
86 static void addr_set_port(nsm_address *, int);
87 static struct addrinfo *host_lookup(int, const char *);
88 void nsm_log(int fac, const char *fmt, ...);
89 static int record_pid();
90 static void drop_privs(void);
92 static struct nsm_host * hosts = NULL;
95 main(int argc, char **argv)
100 while ((c = getopt(argc, argv, "dm:np:v:qP:f")) != -1) {
109 opt_max_retry = atoi(optarg) * 60;
112 opt_update_state = 0;
115 opt_srcport = atoi(optarg);
118 opt_srcaddr = optarg;
124 _SM_BASE_PATH = strdup(optarg);
125 _SM_STATE_PATH = malloc(strlen(optarg)+1+sizeof("state"));
126 _SM_DIR_PATH = malloc(strlen(optarg)+1+sizeof("sm"));
127 _SM_BAK_PATH = malloc(strlen(optarg)+1+sizeof("sm.bak"));
128 if (_SM_BASE_PATH == NULL ||
129 _SM_STATE_PATH == NULL ||
130 _SM_DIR_PATH == NULL ||
131 _SM_BAK_PATH == NULL) {
132 nsm_log(LOG_WARNING, "unable to allocate memory");
135 strcat(strcpy(_SM_STATE_PATH, _SM_BASE_PATH), "/state");
136 strcat(strcpy(_SM_DIR_PATH, _SM_BASE_PATH), "/sm");
137 strcat(strcpy(_SM_BAK_PATH, _SM_BASE_PATH), "/sm.bak");
146 usage: fprintf(stderr,
147 "Usage: sm-notify [-dfq] [-m max-retry-minutes] [-p srcport]\n"
148 " [-P /path/to/state/directory] [-v my_host_name]\n");
152 if (strcmp(_SM_BASE_PATH, BASEDIR) == 0) {
153 if (record_pid() == 0 && force == 0 && opt_update_state == 1)
154 /* already run, don't try again */
159 strncpy(nsm_hostname, opt_srcaddr, sizeof(nsm_hostname)-1);
161 if (gethostname(nsm_hostname, sizeof(nsm_hostname)) < 0) {
162 perror("gethostname");
166 backup_hosts(_SM_DIR_PATH, _SM_BAK_PATH);
167 get_hosts(_SM_BAK_PATH);
171 printf("Backgrounding to notify hosts...\n");
173 openlog("sm-notify", LOG_PID, LOG_DAEMON);
176 if (daemon(0, 0) < 0) {
177 nsm_log(LOG_WARNING, "unable to background: %s",
187 /* Get and update the NSM state. This will call sync() */
188 nsm_state = nsm_get_state(opt_update_state);
195 while ((hp = hosts) != 0) {
198 "Unable to notify %s, giving up",
213 nsm_address local_addr;
217 sock = socket(AF_INET, SOCK_DGRAM, 0);
222 fcntl(sock, F_SETFL, O_NONBLOCK);
224 memset(&local_addr, 0, sizeof(local_addr));
225 local_addr.ss_family = AF_INET; /* Default to IPv4 */
227 /* Bind source IP if provided on command line */
229 struct addrinfo *ai = host_lookup(AF_INET, opt_srcaddr);
232 "Not a valid hostname or address: \"%s\"\n",
236 memcpy(&local_addr, ai->ai_addr, ai->ai_addrlen);
237 /* We know it's IPv4 at this point */
240 /* Use source port if provided on the command line,
241 * otherwise use bindresvport */
243 addr_set_port(&local_addr, opt_srcport);
244 if (bind(sock, (struct sockaddr *) &local_addr, sizeof(local_addr)) < 0) {
249 (void) bindresvport(sock, (struct sockaddr_in *) &local_addr);
253 failtime = time(NULL) + opt_max_retry;
259 time_t now = time(NULL);
260 unsigned int sent = 0;
264 if (failtime && now >= failtime)
267 while ((wait = hosts->send_next - now) <= 0) {
268 /* Never send more than 10 packets at once */
272 /* Remove queue head */
276 notify_host(sock, hp);
278 /* Set the timeout for this call, using an
279 exponential timeout strategy */
281 if ((hp->timeout <<= 1) > NSM_MAX_TIMEOUT)
282 hp->timeout = NSM_MAX_TIMEOUT;
283 hp->send_next = now + wait;
289 nsm_log(LOG_DEBUG, "Host %s due in %ld seconds",
298 if (poll(&pfd, 1, wait) != 1)
306 * Send notification to a single host
309 notify_host(int sock, struct nsm_host *host)
311 static unsigned int xid = 0;
313 uint32_t msgbuf[MAXMSGSIZE], *p;
317 xid = getpid() + time(NULL);
321 memset(msgbuf, 0, sizeof(msgbuf));
323 *p++ = htonl(host->xid);
327 /* If we retransmitted 4 times, reset the port to force
328 * a new portmap lookup (in case statd was restarted).
329 * We also rotate through multiple IP addresses at this
332 if (host->retries >= 4) {
333 struct addrinfo *hold = host->ai;
334 struct addrinfo **next = &host->ai;
335 *next = hold->ai_next;
337 next = & (*next)->ai_next;
339 hold->ai_next = NULL;
340 memcpy(&host->addr, hold->ai_addr, hold->ai_addrlen);
341 addr_set_port(&host->addr, 0);
346 if (addr_get_port(&dest) == 0) {
347 /* Build a PMAP packet */
348 nsm_log(LOG_DEBUG, "Sending portmap query to %s", host->name);
350 addr_set_port(&dest, 111);
351 *p++ = htonl(100000);
359 *p++ = htonl(NSM_PROGRAM);
360 *p++ = htonl(NSM_VERSION);
361 *p++ = htonl(IPPROTO_UDP);
364 /* Build an SM_NOTIFY packet */
365 nsm_log(LOG_DEBUG, "Sending SM_NOTIFY to %s", host->name);
367 *p++ = htonl(NSM_PROGRAM);
368 *p++ = htonl(NSM_VERSION);
369 *p++ = htonl(NSM_NOTIFY);
376 len = strlen(nsm_hostname);
378 memcpy(p, nsm_hostname, len);
380 *p++ = htonl(nsm_state);
382 len = (p - msgbuf) << 2;
384 sendto(sock, msgbuf, len, 0, (struct sockaddr *) &dest, sizeof(dest));
388 * Receive reply from remote host
394 uint32_t msgbuf[MAXMSGSIZE], *p, *end;
398 res = recv(sock, msgbuf, sizeof(msgbuf), 0);
402 nsm_log(LOG_DEBUG, "Received packet...");
405 end = p + (res >> 2);
408 if (*p++ != htonl(1) /* must be REPLY */
409 || *p++ != htonl(0) /* must be ACCEPTED */
410 || *p++ != htonl(0) /* must be NULL verifier */
412 || *p++ != htonl(0)) /* must be SUCCESS */
415 /* Before we look at the data, find the host struct for
417 if ((hp = find_host(xid)) == NULL)
420 if (addr_get_port(&hp->addr) == 0) {
421 /* This was a portmap request */
428 hp->send_next = time(NULL);
430 /* No binding for statd. Delay the next
431 * portmap query for max timeout */
432 nsm_log(LOG_DEBUG, "No statd on %s", hp->name);
433 hp->timeout = NSM_MAX_TIMEOUT;
434 hp->send_next += NSM_MAX_TIMEOUT;
436 addr_set_port(&hp->addr, port);
437 if (hp->timeout >= NSM_MAX_TIMEOUT / 4)
438 hp->timeout = NSM_MAX_TIMEOUT / 4;
442 /* Successful NOTIFY call. Server returns void,
443 * so nothing we need to do here (except
444 * check that we didn't read past the end of the
448 nsm_log(LOG_DEBUG, "Host %s notified successfully", hp->name);
453 freeaddrinfo(hp->ai);
458 fail: /* Re-insert the host */
463 * Back up all hosts from the sm directory to sm.bak
466 backup_hosts(const char *dirname, const char *bakname)
471 if (!(dir = opendir(dirname))) {
476 while ((de = readdir(dir)) != NULL) {
477 char src[1024], dst[1024];
479 if (de->d_name[0] == '.')
482 snprintf(src, sizeof(src), "%s/%s", dirname, de->d_name);
483 snprintf(dst, sizeof(dst), "%s/%s", bakname, de->d_name);
484 if (rename(src, dst) < 0) {
486 "Failed to rename %s -> %s: %m",
494 * Get all entries from sm.bak and convert them to host names
497 get_hosts(const char *dirname)
499 struct nsm_host *host;
503 if (!(dir = opendir(dirname))) {
509 while ((de = readdir(dir)) != NULL) {
513 if (de->d_name[0] == '.')
516 host = calloc(1, sizeof(*host));
518 snprintf(path, sizeof(path), "%s/%s", dirname, de->d_name);
519 if (stat(path, &stb) < 0)
522 host->ai = host_lookup(AF_UNSPEC, de->d_name);
525 "%s doesn't seem to be a valid address, skipped",
531 host->last_used = stb.st_mtime;
532 host->timeout = NSM_TIMEOUT;
533 host->path = strdup(path);
534 host->name = strdup(de->d_name);
535 host->retries = 100; /* force address retry */
547 * Insert host into sorted list
550 insert_host(struct nsm_host *host)
552 struct nsm_host **where, *p;
555 while ((p = *where) != 0) {
556 /* Sort in ascending order of timeout */
557 if (host->send_next < p->send_next)
559 /* If we have the same timeout, put the
560 * most recently used host first.
561 * This makes sure that "recent" hosts
562 * get notified first.
564 if (host->send_next == p->send_next
565 && host->last_used > p->last_used)
575 * Find host given the XID
578 find_host(uint32_t xid)
580 struct nsm_host **where, *p;
583 while ((p = *where) != 0) {
595 * Retrieve the current NSM state
598 nsm_get_state(int update)
600 char newfile[PATH_MAX];
603 if ((fd = open(_SM_STATE_PATH, O_RDONLY)) < 0) {
605 nsm_log(LOG_WARNING, "%s: %m", _SM_STATE_PATH);
606 nsm_log(LOG_WARNING, "Creating %s, set initial state 1",
612 if (read(fd, &state, sizeof(state)) != sizeof(state)) {
614 "%s: bad file size, setting state = 1",
627 snprintf(newfile, sizeof(newfile),
628 "%s.new", _SM_STATE_PATH);
629 if ((fd = open(newfile, O_CREAT|O_WRONLY, 0644)) < 0) {
630 nsm_log(LOG_WARNING, "Cannot create %s: %m", newfile);
633 if (write(fd, &state, sizeof(state)) != sizeof(state)) {
635 "Failed to write state to %s", newfile);
639 if (rename(newfile, _SM_STATE_PATH) < 0) {
641 "Cannot create %s: %m", _SM_STATE_PATH);
651 * Address handling utilities
655 addr_get_port(nsm_address *addr)
657 switch (((struct sockaddr *) addr)->sa_family) {
659 return ntohs(((struct sockaddr_in *) addr)->sin_port);
661 return ntohs(((struct sockaddr_in6 *) addr)->sin6_port);
667 addr_set_port(nsm_address *addr, int port)
669 switch (((struct sockaddr *) addr)->sa_family) {
671 ((struct sockaddr_in *) addr)->sin_port = htons(port);
674 ((struct sockaddr_in6 *) addr)->sin6_port = htons(port);
678 static struct addrinfo *
679 host_lookup(int af, const char *name)
681 struct addrinfo hints, *ai;
683 memset(&hints, 0, sizeof(hints));
684 hints.ai_family = af;
685 hints.ai_protocol = IPPROTO_UDP;
687 if (getaddrinfo(name, NULL, &hints, &ai) != 0)
697 nsm_log(int fac, const char *fmt, ...)
701 if (fac == LOG_DEBUG && !opt_debug)
706 vsyslog(fac, fmt, ap);
708 vfprintf(stderr, fmt, ap);
715 * Record pid in /var/run/sm-notify.pid
716 * This file should remain until a reboot, even if the
718 * If file already exists, fail.
720 static int record_pid()
725 snprintf(pid, 20, "%d\n", getpid());
726 fd = open("/var/run/sm-notify.pid", O_CREAT|O_EXCL|O_WRONLY, 0600);
729 write(fd, pid, strlen(pid));
734 /* Drop privileges to match owner of state-directory
735 * (in case a reply triggers some unknown bug).
737 static void drop_privs(void)
741 if (stat(_SM_DIR_PATH, &st) == -1 &&
742 stat(_SM_BASE_PATH, &st) == -1) {
747 if (st.st_uid == 0) {
749 "sm-notify running as root. chown %s to choose different user\n",
755 if (setgid(st.st_gid) == -1
756 || setuid(st.st_uid) == -1) {
757 nsm_log(LOG_ERR, "Fail to drop privileges");