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(void);
90 static void drop_privs(void);
91 static void set_kernel_nsm_state(int state);
93 static struct nsm_host * hosts = NULL;
96 main(int argc, char **argv)
101 while ((c = getopt(argc, argv, "dm:np:v:qP:f")) != -1) {
110 opt_max_retry = atoi(optarg) * 60;
113 opt_update_state = 0;
116 opt_srcport = atoi(optarg);
119 opt_srcaddr = optarg;
125 _SM_BASE_PATH = strdup(optarg);
126 _SM_STATE_PATH = malloc(strlen(optarg)+1+sizeof("state"));
127 _SM_DIR_PATH = malloc(strlen(optarg)+1+sizeof("sm"));
128 _SM_BAK_PATH = malloc(strlen(optarg)+1+sizeof("sm.bak"));
129 if (_SM_BASE_PATH == NULL ||
130 _SM_STATE_PATH == NULL ||
131 _SM_DIR_PATH == NULL ||
132 _SM_BAK_PATH == NULL) {
133 nsm_log(LOG_WARNING, "unable to allocate memory");
136 strcat(strcpy(_SM_STATE_PATH, _SM_BASE_PATH), "/state");
137 strcat(strcpy(_SM_DIR_PATH, _SM_BASE_PATH), "/sm");
138 strcat(strcpy(_SM_BAK_PATH, _SM_BASE_PATH), "/sm.bak");
147 usage: fprintf(stderr,
148 "Usage: sm-notify [-dfq] [-m max-retry-minutes] [-p srcport]\n"
149 " [-P /path/to/state/directory] [-v my_host_name]\n");
153 if (strcmp(_SM_BASE_PATH, BASEDIR) == 0) {
154 if (record_pid() == 0 && force == 0 && opt_update_state == 1)
155 /* already run, don't try again */
160 strncpy(nsm_hostname, opt_srcaddr, sizeof(nsm_hostname)-1);
162 if (gethostname(nsm_hostname, sizeof(nsm_hostname)) < 0) {
163 perror("gethostname");
167 backup_hosts(_SM_DIR_PATH, _SM_BAK_PATH);
168 get_hosts(_SM_BAK_PATH);
170 /* Get and update the NSM state. This will call sync() */
171 nsm_state = nsm_get_state(opt_update_state);
172 set_kernel_nsm_state(nsm_state);
176 printf("Backgrounding to notify hosts...\n");
178 openlog("sm-notify", LOG_PID, LOG_DAEMON);
181 if (daemon(0, 0) < 0) {
182 nsm_log(LOG_WARNING, "unable to background: %s",
197 while ((hp = hosts) != 0) {
200 "Unable to notify %s, giving up",
215 nsm_address local_addr;
221 sock = socket(AF_INET, SOCK_DGRAM, 0);
226 fcntl(sock, F_SETFL, O_NONBLOCK);
228 memset(&local_addr, 0, sizeof(local_addr));
229 local_addr.ss_family = AF_INET; /* Default to IPv4 */
231 /* Bind source IP if provided on command line */
233 struct addrinfo *ai = host_lookup(AF_INET, opt_srcaddr);
236 "Not a valid hostname or address: \"%s\"\n",
240 memcpy(&local_addr, ai->ai_addr, ai->ai_addrlen);
241 /* We know it's IPv4 at this point */
244 /* Use source port if provided on the command line,
245 * otherwise use bindresvport */
247 addr_set_port(&local_addr, opt_srcport);
248 if (bind(sock, (struct sockaddr *) &local_addr, sizeof(local_addr)) < 0) {
254 struct sockaddr_in *sin = (struct sockaddr_in *)&local_addr;
255 (void) bindresvport(sock, sin);
256 /* try to avoid known ports */
257 se = getservbyport(sin->sin_port, "udp");
258 if (se && retry_cnt < 100) {
266 failtime = time(NULL) + opt_max_retry;
272 time_t now = time(NULL);
273 unsigned int sent = 0;
277 if (failtime && now >= failtime)
280 while ((wait = hosts->send_next - now) <= 0) {
281 /* Never send more than 10 packets at once */
285 /* Remove queue head */
289 notify_host(sock, hp);
291 /* Set the timeout for this call, using an
292 exponential timeout strategy */
294 if ((hp->timeout <<= 1) > NSM_MAX_TIMEOUT)
295 hp->timeout = NSM_MAX_TIMEOUT;
296 hp->send_next = now + wait;
302 nsm_log(LOG_DEBUG, "Host %s due in %ld seconds",
311 if (poll(&pfd, 1, wait) != 1)
319 * Send notification to a single host
322 notify_host(int sock, struct nsm_host *host)
324 static unsigned int xid = 0;
326 uint32_t msgbuf[MAXMSGSIZE], *p;
330 xid = getpid() + time(NULL);
334 memset(msgbuf, 0, sizeof(msgbuf));
336 *p++ = htonl(host->xid);
340 /* If we retransmitted 4 times, reset the port to force
341 * a new portmap lookup (in case statd was restarted).
342 * We also rotate through multiple IP addresses at this
345 if (host->retries >= 4) {
346 struct addrinfo *hold = host->ai;
347 struct addrinfo **next = &host->ai;
348 *next = hold->ai_next;
350 next = & (*next)->ai_next;
352 hold->ai_next = NULL;
353 memcpy(&host->addr, hold->ai_addr, hold->ai_addrlen);
354 addr_set_port(&host->addr, 0);
359 if (addr_get_port(&dest) == 0) {
360 /* Build a PMAP packet */
361 nsm_log(LOG_DEBUG, "Sending portmap query to %s", host->name);
363 addr_set_port(&dest, 111);
364 *p++ = htonl(100000);
372 *p++ = htonl(NSM_PROGRAM);
373 *p++ = htonl(NSM_VERSION);
374 *p++ = htonl(IPPROTO_UDP);
377 /* Build an SM_NOTIFY packet */
378 nsm_log(LOG_DEBUG, "Sending SM_NOTIFY to %s", host->name);
380 *p++ = htonl(NSM_PROGRAM);
381 *p++ = htonl(NSM_VERSION);
382 *p++ = htonl(NSM_NOTIFY);
389 len = strlen(nsm_hostname);
391 memcpy(p, nsm_hostname, len);
393 *p++ = htonl(nsm_state);
395 len = (p - msgbuf) << 2;
397 sendto(sock, msgbuf, len, 0, (struct sockaddr *) &dest, sizeof(dest));
401 * Receive reply from remote host
407 uint32_t msgbuf[MAXMSGSIZE], *p, *end;
411 res = recv(sock, msgbuf, sizeof(msgbuf), 0);
415 nsm_log(LOG_DEBUG, "Received packet...");
418 end = p + (res >> 2);
421 if (*p++ != htonl(1) /* must be REPLY */
422 || *p++ != htonl(0) /* must be ACCEPTED */
423 || *p++ != htonl(0) /* must be NULL verifier */
425 || *p++ != htonl(0)) /* must be SUCCESS */
428 /* Before we look at the data, find the host struct for
430 if ((hp = find_host(xid)) == NULL)
433 if (addr_get_port(&hp->addr) == 0) {
434 /* This was a portmap request */
441 hp->send_next = time(NULL);
443 /* No binding for statd. Delay the next
444 * portmap query for max timeout */
445 nsm_log(LOG_DEBUG, "No statd on %s", hp->name);
446 hp->timeout = NSM_MAX_TIMEOUT;
447 hp->send_next += NSM_MAX_TIMEOUT;
449 addr_set_port(&hp->addr, port);
450 if (hp->timeout >= NSM_MAX_TIMEOUT / 4)
451 hp->timeout = NSM_MAX_TIMEOUT / 4;
455 /* Successful NOTIFY call. Server returns void,
456 * so nothing we need to do here (except
457 * check that we didn't read past the end of the
461 nsm_log(LOG_DEBUG, "Host %s notified successfully", hp->name);
466 freeaddrinfo(hp->ai);
471 fail: /* Re-insert the host */
476 * Back up all hosts from the sm directory to sm.bak
479 backup_hosts(const char *dirname, const char *bakname)
484 if (!(dir = opendir(dirname))) {
489 while ((de = readdir(dir)) != NULL) {
490 char src[1024], dst[1024];
492 if (de->d_name[0] == '.')
495 snprintf(src, sizeof(src), "%s/%s", dirname, de->d_name);
496 snprintf(dst, sizeof(dst), "%s/%s", bakname, de->d_name);
497 if (rename(src, dst) < 0) {
499 "Failed to rename %s -> %s: %m",
507 * Get all entries from sm.bak and convert them to host names
510 get_hosts(const char *dirname)
512 struct nsm_host *host;
516 if (!(dir = opendir(dirname))) {
522 while ((de = readdir(dir)) != NULL) {
526 if (de->d_name[0] == '.')
529 host = calloc(1, sizeof(*host));
531 snprintf(path, sizeof(path), "%s/%s", dirname, de->d_name);
532 if (stat(path, &stb) < 0)
535 host->ai = host_lookup(AF_UNSPEC, de->d_name);
538 "%s doesn't seem to be a valid address, skipped",
544 host->last_used = stb.st_mtime;
545 host->timeout = NSM_TIMEOUT;
546 host->path = strdup(path);
547 host->name = strdup(de->d_name);
548 host->retries = 100; /* force address retry */
560 * Insert host into sorted list
563 insert_host(struct nsm_host *host)
565 struct nsm_host **where, *p;
568 while ((p = *where) != 0) {
569 /* Sort in ascending order of timeout */
570 if (host->send_next < p->send_next)
572 /* If we have the same timeout, put the
573 * most recently used host first.
574 * This makes sure that "recent" hosts
575 * get notified first.
577 if (host->send_next == p->send_next
578 && host->last_used > p->last_used)
588 * Find host given the XID
591 find_host(uint32_t xid)
593 struct nsm_host **where, *p;
596 while ((p = *where) != 0) {
608 * Retrieve the current NSM state
611 nsm_get_state(int update)
613 char newfile[PATH_MAX];
616 if ((fd = open(_SM_STATE_PATH, O_RDONLY)) < 0) {
618 nsm_log(LOG_WARNING, "%s: %m", _SM_STATE_PATH);
619 nsm_log(LOG_WARNING, "Creating %s, set initial state 1",
625 if (read(fd, &state, sizeof(state)) != sizeof(state)) {
627 "%s: bad file size, setting state = 1",
640 snprintf(newfile, sizeof(newfile),
641 "%s.new", _SM_STATE_PATH);
642 if ((fd = open(newfile, O_CREAT|O_WRONLY, 0644)) < 0) {
643 nsm_log(LOG_WARNING, "Cannot create %s: %m", newfile);
646 if (write(fd, &state, sizeof(state)) != sizeof(state)) {
648 "Failed to write state to %s", newfile);
652 if (rename(newfile, _SM_STATE_PATH) < 0) {
654 "Cannot create %s: %m", _SM_STATE_PATH);
664 * Address handling utilities
668 addr_get_port(nsm_address *addr)
670 switch (((struct sockaddr *) addr)->sa_family) {
672 return ntohs(((struct sockaddr_in *) addr)->sin_port);
674 return ntohs(((struct sockaddr_in6 *) addr)->sin6_port);
680 addr_set_port(nsm_address *addr, int port)
682 switch (((struct sockaddr *) addr)->sa_family) {
684 ((struct sockaddr_in *) addr)->sin_port = htons(port);
687 ((struct sockaddr_in6 *) addr)->sin6_port = htons(port);
691 static struct addrinfo *
692 host_lookup(int af, const char *name)
694 struct addrinfo hints, *ai;
696 memset(&hints, 0, sizeof(hints));
697 hints.ai_family = af;
698 hints.ai_protocol = IPPROTO_UDP;
700 if (getaddrinfo(name, NULL, &hints, &ai) != 0)
710 nsm_log(int fac, const char *fmt, ...)
714 if (fac == LOG_DEBUG && !opt_debug)
719 vsyslog(fac, fmt, ap);
721 vfprintf(stderr, fmt, ap);
728 * Record pid in /var/run/sm-notify.pid
729 * This file should remain until a reboot, even if the
731 * If file already exists, fail.
733 static int record_pid(void)
738 snprintf(pid, 20, "%d\n", getpid());
739 fd = open("/var/run/sm-notify.pid", O_CREAT|O_EXCL|O_WRONLY, 0600);
742 write(fd, pid, strlen(pid));
747 /* Drop privileges to match owner of state-directory
748 * (in case a reply triggers some unknown bug).
750 static void drop_privs(void)
754 if (stat(_SM_DIR_PATH, &st) == -1 &&
755 stat(_SM_BASE_PATH, &st) == -1) {
760 if (st.st_uid == 0) {
762 "sm-notify running as root. chown %s to choose different user\n",
768 if (setgid(st.st_gid) == -1
769 || setuid(st.st_uid) == -1) {
770 nsm_log(LOG_ERR, "Fail to drop privileges");
775 static void set_kernel_nsm_state(int state)
779 fd = open("/proc/sys/fs/nfs/nsm_local_state",O_WRONLY);
782 snprintf(buf, sizeof(buf), "%d", state);
783 write(fd, buf, strlen(buf));