utils/statd/sm-notify.c

   1 /*
   2  * Send NSM notify calls to all hosts listed in /var/lib/sm
   3  *
   4  * Copyright (C) 2004-2006 Olaf Kirch <okir@suse.de>
   5  */
   6
   7 #include <sys/types.h>
   8 #include <sys/socket.h>
   9 #include <sys/stat.h>
  10 #include <sys/poll.h>
  11 #include <sys/param.h>
  12 #include <sys/syslog.h>
  13 #include <arpa/inet.h>
  14 #include <dirent.h>
  15 #include <time.h>
  16 #include <stdio.h>
  17 #include <getopt.h>
  18 #include <stdlib.h>
  19 #include <fcntl.h>
  20 #include <unistd.h>
  21 #include <string.h>
  22 #include <stdarg.h>
  23 #include <netdb.h>
  24 #include <errno.h>
  25
  26 #ifndef BASEDIR
  27 #define BASEDIR         "/var/lib/nfs"
  28 #endif
  29
  30 #define DEFAULT_SM_STATE_PATH   BASEDIR "/state"
  31 #define DEFAULT_SM_DIR_PATH     BASEDIR "/sm"
  32 #define DEFAULT_SM_BAK_PATH     DEFAULT_SM_DIR_PATH ".bak"
  33
  34 char *_SM_BASE_PATH = BASEDIR;
  35 char *_SM_STATE_PATH = DEFAULT_SM_STATE_PATH;
  36 char *_SM_DIR_PATH = DEFAULT_SM_DIR_PATH;
  37 char *_SM_BAK_PATH = DEFAULT_SM_BAK_PATH;
  38
  39 #define NSM_PROG        100024
  40 #define NSM_PROGRAM     100024
  41 #define NSM_VERSION     1
  42 #define NSM_TIMEOUT     2
  43 #define NSM_NOTIFY      6
  44 #define NSM_MAX_TIMEOUT 120     /* don't make this too big */
  45 #define MAXMSGSIZE      256
  46
  47 typedef struct sockaddr_storage nsm_address;
  48
  49 struct nsm_host {
  50         struct nsm_host *       next;
  51         char *                  name;
  52         char *                  path;
  53         nsm_address             addr;
  54         time_t                  last_used;
  55         time_t                  send_next;
  56         unsigned int            timeout;
  57         unsigned int            retries;
  58         unsigned int            xid;
  59 };
  60
  61 static char             nsm_hostname[256];
  62 static uint32_t         nsm_state;
  63 static int              opt_debug = 0;
  64 static int              opt_quiet = 0;
  65 static int              opt_update_state = 1;
  66 static unsigned int     opt_max_retry = 15 * 60;
  67 static char *           opt_srcaddr = 0;
  68 static uint16_t         opt_srcport = 0;
  69 static int              log_syslog = 0;
  70
  71 static unsigned int     nsm_get_state(int);
  72 static void             notify(void);
  73 static void             notify_host(int, struct nsm_host *);
  74 static void             recv_reply(int);
  75 static void             backup_hosts(const char *, const char *);
  76 static void             get_hosts(const char *);
  77 static void             insert_host(struct nsm_host *);
  78 struct nsm_host *       find_host(uint32_t);
  79 static int              addr_parse(int, const char *, nsm_address *);
  80 static int              addr_get_port(nsm_address *);
  81 static void             addr_set_port(nsm_address *, int);
  82 static int              host_lookup(int, const char *, nsm_address *);
  83 void                    nsm_log(int fac, const char *fmt, ...);
  84
  85 static struct nsm_host *        hosts = NULL;
  86
  87 int
  88 main(int argc, char **argv)
  89 {
  90         int     c;
  91
  92         while ((c = getopt(argc, argv, "dm:np:v:qP:")) != -1) {
  93                 switch (c) {
  94                 case 'd':
  95                         opt_debug++;
  96                         break;
  97                 case 'm':
  98                         opt_max_retry = atoi(optarg) * 60;
  99                         break;
 100                 case 'n':
 101                         opt_update_state = 0;
 102                         break;
 103                 case 'p':
 104                         opt_srcport = atoi(optarg);
 105                         break;
 106                 case 'v':
 107                         opt_srcaddr = optarg;
 108                         break;
 109                 case 'q':
 110                         opt_quiet = 1;
 111                         break;
 112                 case 'P':
 113                         _SM_BASE_PATH = strdup(optarg);
 114                         _SM_STATE_PATH = malloc(strlen(optarg)+1+sizeof("state"));
 115                         _SM_DIR_PATH = malloc(strlen(optarg)+1+sizeof("sm"));
 116                         _SM_BAK_PATH = malloc(strlen(optarg)+1+sizeof("sm.bak"));
 117                         if (_SM_BASE_PATH == NULL ||
 118                             _SM_STATE_PATH == NULL ||
 119                             _SM_DIR_PATH == NULL ||
 120                             _SM_BAK_PATH == NULL) {
 121                                 nsm_log(LOG_WARNING, "unable to allocate memory");
 122                                 exit(1);
 123                         }
 124                         strcat(strcpy(_SM_STATE_PATH, _SM_BASE_PATH), "/state");
 125                         strcat(strcpy(_SM_DIR_PATH, _SM_BASE_PATH), "/sm");
 126                         strcat(strcpy(_SM_BAK_PATH, _SM_BASE_PATH), "/sm.bak");
 127                         break;
 128
 129                 default:
 130                         goto usage;
 131                 }
 132         }
 133
 134         if (optind < argc) {
 135 usage:          fprintf(stderr, "sm-notify [-d]\n");
 136                 return 1;
 137         }
 138
 139         if (opt_srcaddr) {
 140                 strncpy(nsm_hostname, opt_srcaddr, sizeof(nsm_hostname)-1);
 141         } else
 142         if (gethostname(nsm_hostname, sizeof(nsm_hostname)) < 0) {
 143                 perror("gethostname");
 144                 return 1;
 145         }
 146
 147         backup_hosts(_SM_DIR_PATH, _SM_BAK_PATH);
 148         get_hosts(_SM_BAK_PATH);
 149
 150         if (!opt_debug) {
 151                 if (!opt_quiet)
 152                         printf("Backgrounding to notify hosts...\n");
 153
 154                 openlog("sm-notify", LOG_PID, LOG_DAEMON);
 155                 log_syslog = 1;
 156
 157                 if (daemon(0, 0) < 0) {
 158                         nsm_log(LOG_WARNING, "unable to background: %s",
 159                                         strerror(errno));
 160                         return 1;
 161                 }
 162
 163                 close(0);
 164                 close(1);
 165                 close(2);
 166         }
 167
 168         /* Get and update the NSM state. This will call sync() */
 169         nsm_state = nsm_get_state(opt_update_state);
 170
 171         notify();
 172
 173         if (hosts) {
 174                 struct nsm_host *hp;
 175
 176                 while ((hp = hosts) != 0) {
 177                         hosts = hp->next;
 178                         nsm_log(LOG_NOTICE,
 179                                 "Unable to notify %s, giving up",
 180                                 hp->name);
 181                 }
 182                 return 1;
 183         }
 184
 185         return 0;
 186 }
 187
 188 /*
 189  * Notify hosts
 190  */
 191 void
 192 notify(void)
 193 {
 194         nsm_address local_addr;
 195         time_t  failtime = 0;
 196         int     sock = -1;
 197
 198         sock = socket(AF_INET, SOCK_DGRAM, 0);
 199         if (sock < 0) {
 200                 perror("socket");
 201                 exit(1);
 202         }
 203         fcntl(sock, F_SETFL, O_NONBLOCK);
 204
 205         memset(&local_addr, 0, sizeof(local_addr));
 206         local_addr.ss_family = AF_INET; /* Default to IPv4 */
 207
 208         /* Bind source IP if provided on command line */
 209         if (opt_srcaddr) {
 210                 if (!addr_parse(AF_INET, opt_srcaddr, &local_addr)
 211                  && !host_lookup(AF_INET, opt_srcaddr, &local_addr)) {
 212                         nsm_log(LOG_WARNING,
 213                                 "Not a valid hostname or address: \"%s\"\n",
 214                                 opt_srcaddr);
 215                         exit(1);
 216                 }
 217                 /* We know it's IPv4 at this point */
 218         }
 219
 220         /* Use source port if provided on the command line,
 221          * otherwise use bindresvport */
 222         if (opt_srcport) {
 223                 addr_set_port(&local_addr, opt_srcport);
 224                 if (bind(sock, (struct sockaddr *) &local_addr, sizeof(local_addr)) < 0) {
 225                         perror("bind");
 226                         exit(1);
 227                 }
 228         } else {
 229                 (void) bindresvport(sock, (struct sockaddr_in *) &local_addr);
 230         }
 231
 232         if (opt_max_retry)
 233                 failtime = time(NULL) + opt_max_retry;
 234
 235         while (hosts) {
 236                 struct pollfd   pfd;
 237                 time_t          now = time(NULL);
 238                 unsigned int    sent = 0;
 239                 struct nsm_host *hp;
 240                 long            wait;
 241
 242                 if (failtime && now >= failtime)
 243                         break;
 244
 245                 while ((wait = hosts->send_next - now) <= 0) {
 246                         /* Never send more than 10 packets at once */
 247                         if (sent++ >= 10)
 248                                 break;
 249
 250                         /* Remove queue head */
 251                         hp = hosts;
 252                         hosts = hp->next;
 253
 254                         notify_host(sock, hp);
 255
 256                         /* Set the timeout for this call, using an
 257                            exponential timeout strategy */
 258                         wait = hp->timeout;
 259                         if ((hp->timeout <<= 1) > NSM_MAX_TIMEOUT)
 260                                 hp->timeout = NSM_MAX_TIMEOUT;
 261                         hp->send_next = now + wait;
 262                         hp->retries++;
 263
 264                         insert_host(hp);
 265                 }
 266
 267                 nsm_log(LOG_DEBUG, "Host %s due in %ld seconds",
 268                                 hosts->name, wait);
 269
 270                 pfd.fd = sock;
 271                 pfd.events = POLLIN;
 272
 273                 wait *= 1000;
 274                 if (wait < 100)
 275                         wait = 100;
 276                 if (poll(&pfd, 1, wait) != 1)
 277                         continue;
 278
 279                 recv_reply(sock);
 280         }
 281 }
 282
 283 /*
 284  * Send notification to a single host
 285  */
 286 void
 287 notify_host(int sock, struct nsm_host *host)
 288 {
 289         static unsigned int     xid = 0;
 290         nsm_address             dest;
 291         uint32_t                msgbuf[MAXMSGSIZE], *p;
 292         unsigned int            len;
 293
 294         if (!xid)
 295                 xid = getpid() + time(NULL);
 296         if (!host->xid)
 297                 host->xid = xid++;
 298
 299         memset(msgbuf, 0, sizeof(msgbuf));
 300         p = msgbuf;
 301         *p++ = htonl(host->xid);
 302         *p++ = 0;
 303         *p++ = htonl(2);
 304
 305         /* If we retransmitted 4 times, reset the port to force
 306          * a new portmap lookup (in case statd was restarted)
 307          */
 308         if (host->retries >= 4) {
 309                 addr_set_port(&host->addr, 0);
 310                 host->retries = 0;
 311         }
 312
 313         dest = host->addr;
 314         if (addr_get_port(&dest) == 0) {
 315                 /* Build a PMAP packet */
 316                 nsm_log(LOG_DEBUG, "Sending portmap query to %s", host->name);
 317
 318                 addr_set_port(&dest, 111);
 319                 *p++ = htonl(100000);
 320                 *p++ = htonl(2);
 321                 *p++ = htonl(3);
 322
 323                 /* Auth and verf */
 324                 *p++ = 0; *p++ = 0;
 325                 *p++ = 0; *p++ = 0;
 326
 327                 *p++ = htonl(NSM_PROGRAM);
 328                 *p++ = htonl(NSM_VERSION);
 329                 *p++ = htonl(IPPROTO_UDP);
 330                 *p++ = 0;
 331         } else {
 332                 /* Build an SM_NOTIFY packet */
 333                 nsm_log(LOG_DEBUG, "Sending SM_NOTIFY to %s", host->name);
 334
 335                 *p++ = htonl(NSM_PROGRAM);
 336                 *p++ = htonl(NSM_VERSION);
 337                 *p++ = htonl(NSM_NOTIFY);
 338
 339                 /* Auth and verf */
 340                 *p++ = 0; *p++ = 0;
 341                 *p++ = 0; *p++ = 0;
 342
 343                 /* state change */
 344                 len = strlen(nsm_hostname);
 345                 *p++ = htonl(len);
 346                 memcpy(p, nsm_hostname, len);
 347                 p += (len + 3) >> 2;
 348                 *p++ = htonl(nsm_state);
 349         }
 350         len = (p - msgbuf) << 2;
 351
 352         sendto(sock, msgbuf, len, 0, (struct sockaddr *) &dest, sizeof(dest));
 353 }
 354
 355 /*
 356  * Receive reply from remote host
 357  */
 358 void
 359 recv_reply(int sock)
 360 {
 361         struct nsm_host *hp;
 362         uint32_t        msgbuf[MAXMSGSIZE], *p, *end;
 363         uint32_t        xid;
 364         int             res;
 365
 366         res = recv(sock, msgbuf, sizeof(msgbuf), 0);
 367         if (res < 0)
 368                 return;
 369
 370         nsm_log(LOG_DEBUG, "Received packet...");
 371
 372         p = msgbuf;
 373         end = p + (res >> 2);
 374
 375         xid = ntohl(*p++);
 376         if (*p++ != htonl(1)    /* must be REPLY */
 377          || *p++ != htonl(0)    /* must be ACCEPTED */
 378          || *p++ != htonl(0)    /* must be NULL verifier */
 379          || *p++ != htonl(0)
 380          || *p++ != htonl(0))   /* must be SUCCESS */
 381                 return;
 382
 383         /* Before we look at the data, find the host struct for
 384            this reply */
 385         if ((hp = find_host(xid)) == NULL)
 386                 return;
 387
 388         if (addr_get_port(&hp->addr) == 0) {
 389                 /* This was a portmap request */
 390                 unsigned int    port;
 391
 392                 port = ntohl(*p++);
 393                 if (p > end)
 394                         goto fail;
 395
 396                 hp->send_next = time(NULL);
 397                 if (port == 0) {
 398                         /* No binding for statd. Delay the next
 399                          * portmap query for max timeout */
 400                         nsm_log(LOG_DEBUG, "No statd on %s", hp->name);
 401                         hp->timeout = NSM_MAX_TIMEOUT;
 402                         hp->send_next += NSM_MAX_TIMEOUT;
 403                 } else {
 404                         addr_set_port(&hp->addr, port);
 405                         if (hp->timeout >= NSM_MAX_TIMEOUT / 4)
 406                                 hp->timeout = NSM_MAX_TIMEOUT / 4;
 407                 }
 408                 hp->xid = 0;
 409         } else {
 410                 /* Successful NOTIFY call. Server returns void,
 411                  * so nothing we need to do here (except
 412                  * check that we didn't read past the end of the
 413                  * packet)
 414                  */
 415                 if (p <= end) {
 416                         nsm_log(LOG_DEBUG, "Host %s notified successfully", hp->name);
 417                         unlink(hp->path);
 418                         free(hp->name);
 419                         free(hp->path);
 420                         free(hp);
 421                         return;
 422                 }
 423         }
 424
 425 fail:   /* Re-insert the host */
 426         insert_host(hp);
 427 }
 428
 429 /*
 430  * Back up all hosts from the sm directory to sm.bak
 431  */
 432 static void
 433 backup_hosts(const char *dirname, const char *bakname)
 434 {
 435         struct dirent   *de;
 436         DIR             *dir;
 437
 438         if (!(dir = opendir(dirname))) {
 439                 perror(dirname);
 440                 return;
 441         }
 442
 443         while ((de = readdir(dir)) != NULL) {
 444                 char    src[1024], dst[1024];
 445
 446                 if (de->d_name[0] == '.')
 447                         continue;
 448
 449                 snprintf(src, sizeof(src), "%s/%s", dirname, de->d_name);
 450                 snprintf(dst, sizeof(dst), "%s/%s", bakname, de->d_name);
 451                 if (rename(src, dst) < 0) {
 452                         nsm_log(LOG_WARNING,
 453                                 "Failed to rename %s -> %s: %m",
 454                                 src, dst);
 455                 }
 456         }
 457         closedir(dir);
 458 }
 459
 460 /*
 461  * Get all entries from sm.bak and convert them to host names
 462  */
 463 static void
 464 get_hosts(const char *dirname)
 465 {
 466         struct nsm_host *host;
 467         struct dirent   *de;
 468         DIR             *dir;
 469
 470         if (!(dir = opendir(dirname))) {
 471                 perror(dirname);
 472                 return;
 473         }
 474
 475         host = NULL;
 476         while ((de = readdir(dir)) != NULL) {
 477                 struct stat     stb;
 478                 char            path[1024];
 479
 480                 if (de->d_name[0] == '.')
 481                         continue;
 482                 if (host == NULL)
 483                         host = calloc(1, sizeof(*host));
 484
 485                 snprintf(path, sizeof(path), "%s/%s", dirname, de->d_name);
 486                 if (!addr_parse(AF_INET, de->d_name, &host->addr)
 487                  && !addr_parse(AF_INET6, de->d_name, &host->addr)
 488                  && !host_lookup(AF_INET, de->d_name, &host->addr)) {
 489                         nsm_log(LOG_WARNING,
 490                                 "%s doesn't seem to be a valid address, skipped",
 491                                 de->d_name);
 492                         unlink(path);
 493                         continue;
 494                 }
 495
 496                 if (stat(path, &stb) < 0)
 497                         continue;
 498                 host->last_used = stb.st_mtime;
 499                 host->timeout = NSM_TIMEOUT;
 500                 host->path = strdup(path);
 501                 host->name = strdup(de->d_name);
 502
 503                 insert_host(host);
 504                 host = NULL;
 505         }
 506         closedir(dir);
 507
 508         if (host)
 509                 free(host);
 510 }
 511
 512 /*
 513  * Insert host into sorted list
 514  */
 515 void
 516 insert_host(struct nsm_host *host)
 517 {
 518         struct nsm_host **where, *p;
 519
 520         where = &hosts;
 521         while ((p = *where) != 0) {
 522                 /* Sort in ascending order of timeout */
 523                 if (host->send_next < p->send_next)
 524                         break;
 525                 /* If we have the same timeout, put the
 526                  * most recently used host first.
 527                  * This makes sure that "recent" hosts
 528                  * get notified first.
 529                  */
 530                 if (host->send_next == p->send_next
 531                  && host->last_used > p->last_used)
 532                         break;
 533                 where = &p->next;
 534         }
 535
 536         host->next = *where;
 537         *where = host;
 538 }
 539
 540 /*
 541  * Find host given the XID
 542  */
 543 struct nsm_host *
 544 find_host(uint32_t xid)
 545 {
 546         struct nsm_host **where, *p;
 547
 548         where = &hosts;
 549         while ((p = *where) != 0) {
 550                 if (p->xid == xid) {
 551                         *where = p->next;
 552                         return p;
 553                 }
 554                 where = &p->next;
 555         }
 556         return NULL;
 557 }
 558
 559
 560 /*
 561  * Retrieve the current NSM state
 562  */
 563 unsigned int
 564 nsm_get_state(int update)
 565 {
 566         char            newfile[PATH_MAX];
 567         int             fd, state;
 568
 569         if ((fd = open(_SM_STATE_PATH, O_RDONLY)) < 0) {
 570                 if (!opt_quiet) {
 571                         nsm_log(LOG_WARNING, "%s: %m", _SM_STATE_PATH);
 572                         nsm_log(LOG_WARNING, "Creating %s, set initial state 1",
 573                                 _SM_STATE_PATH);
 574                 }
 575                 state = 1;
 576                 update = 1;
 577         } else {
 578                 if (read(fd, &state, sizeof(state)) != sizeof(state)) {
 579                         nsm_log(LOG_WARNING,
 580                                 "%s: bad file size, setting state = 1",
 581                                 _SM_STATE_PATH);
 582                         state = 1;
 583                         update = 1;
 584                 } else {
 585                         if (!(state & 1))
 586                                 state += 1;
 587                 }
 588                 close(fd);
 589         }
 590
 591         if (update) {
 592                 state += 2;
 593                 snprintf(newfile, sizeof(newfile),
 594                                 "%s.new", _SM_STATE_PATH);
 595                 if ((fd = open(newfile, O_CREAT|O_WRONLY, 0644)) < 0) {
 596                         nsm_log(LOG_WARNING, "Cannot create %s: %m", newfile);
 597                         exit(1);
 598                 }
 599                 if (write(fd, &state, sizeof(state)) != sizeof(state)) {
 600                         nsm_log(LOG_WARNING,
 601                                 "Failed to write state to %s", newfile);
 602                         exit(1);
 603                 }
 604                 close(fd);
 605                 if (rename(newfile, _SM_STATE_PATH) < 0) {
 606                         nsm_log(LOG_WARNING,
 607                                 "Cannot create %s: %m", _SM_STATE_PATH);
 608                         exit(1);
 609                 }
 610                 sync();
 611         }
 612
 613         return state;
 614 }
 615
 616 /*
 617  * Address handling utilities
 618  */
 619 static int
 620 addr_parse(int af, const char *name, nsm_address *addr)
 621 {
 622         void    *ptr;
 623
 624         if (af == AF_INET)
 625                 ptr = &((struct sockaddr_in *) addr)->sin_addr;
 626         else if (af == AF_INET6)
 627                 ptr = &((struct sockaddr_in6 *) addr)->sin6_addr;
 628         else
 629                 return 0;
 630         if (inet_pton(af, name, ptr) <= 0)
 631                 return 0;
 632         ((struct sockaddr *) addr)->sa_family = af;
 633         return 1;
 634 }
 635
 636 int
 637 addr_get_port(nsm_address *addr)
 638 {
 639         switch (((struct sockaddr *) addr)->sa_family) {
 640         case AF_INET:
 641                 return ntohs(((struct sockaddr_in *) addr)->sin_port);
 642         case AF_INET6:
 643                 return ntohs(((struct sockaddr_in6 *) addr)->sin6_port);
 644         }
 645         return 0;
 646 }
 647
 648 static void
 649 addr_set_port(nsm_address *addr, int port)
 650 {
 651         switch (((struct sockaddr *) addr)->sa_family) {
 652         case AF_INET:
 653                 ((struct sockaddr_in *) addr)->sin_port = htons(port);
 654                 break;
 655         case AF_INET6:
 656                 ((struct sockaddr_in6 *) addr)->sin6_port = htons(port);
 657         }
 658 }
 659
 660 static int
 661 host_lookup(int af, const char *name, nsm_address *addr)
 662 {
 663         struct addrinfo hints, *ai;
 664         int okay = 0;
 665
 666         memset(&hints, 0, sizeof(hints));
 667         hints.ai_family = af;
 668
 669         if (getaddrinfo(name, NULL, &hints, &ai) != 0)
 670                 return 0;
 671
 672         if (ai->ai_addrlen < sizeof(*addr)) {
 673                 memcpy(addr, ai->ai_addr, ai->ai_addrlen);
 674                 okay = 1;
 675         }
 676
 677         freeaddrinfo(ai);
 678         return okay;
 679 }
 680
 681 /*
 682  * Log a message
 683  */
 684 void
 685 nsm_log(int fac, const char *fmt, ...)
 686 {
 687         va_list ap;
 688
 689         if (fac == LOG_DEBUG && !opt_debug)
 690                 return;
 691
 692         va_start(ap, fmt);
 693         if (log_syslog)
 694                 vsyslog(fac, fmt, ap);
 695         else {
 696                 vfprintf(stderr, fmt, ap);
 697                 fputs("\n", stderr);
 698         }
 699         va_end(ap);
 700 }