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 #include <grp.h>
  26
  27 #ifndef BASEDIR
  28 #define BASEDIR         "/var/lib/nfs"
  29 #endif
  30
  31 #define DEFAULT_SM_STATE_PATH   BASEDIR "/state"
  32 #define DEFAULT_SM_DIR_PATH     BASEDIR "/sm"
  33 #define DEFAULT_SM_BAK_PATH     DEFAULT_SM_DIR_PATH ".bak"
  34
  35 char *_SM_BASE_PATH = BASEDIR;
  36 char *_SM_STATE_PATH = DEFAULT_SM_STATE_PATH;
  37 char *_SM_DIR_PATH = DEFAULT_SM_DIR_PATH;
  38 char *_SM_BAK_PATH = DEFAULT_SM_BAK_PATH;
  39
  40 #define NSM_PROG        100024
  41 #define NSM_PROGRAM     100024
  42 #define NSM_VERSION     1
  43 #define NSM_TIMEOUT     2
  44 #define NSM_NOTIFY      6
  45 #define NSM_MAX_TIMEOUT 120     /* don't make this too big */
  46 #define MAXMSGSIZE      256
  47
  48 typedef struct sockaddr_storage nsm_address;
  49
  50 struct nsm_host {
  51         struct nsm_host *       next;
  52         char *                  name;
  53         char *                  path;
  54         nsm_address             addr;
  55         time_t                  last_used;
  56         time_t                  send_next;
  57         unsigned int            timeout;
  58         unsigned int            retries;
  59         unsigned int            xid;
  60 };
  61
  62 static char             nsm_hostname[256];
  63 static uint32_t         nsm_state;
  64 static int              opt_debug = 0;
  65 static int              opt_quiet = 0;
  66 static int              opt_update_state = 1;
  67 static unsigned int     opt_max_retry = 15 * 60;
  68 static char *           opt_srcaddr = 0;
  69 static uint16_t         opt_srcport = 0;
  70 static int              log_syslog = 0;
  71
  72 static unsigned int     nsm_get_state(int);
  73 static void             notify(void);
  74 static void             notify_host(int, struct nsm_host *);
  75 static void             recv_reply(int);
  76 static void             backup_hosts(const char *, const char *);
  77 static void             get_hosts(const char *);
  78 static void             insert_host(struct nsm_host *);
  79 struct nsm_host *       find_host(uint32_t);
  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 static int              record_pid();
  85 static void             drop_privs(void);
  86
  87 static struct nsm_host *        hosts = NULL;
  88
  89 int
  90 main(int argc, char **argv)
  91 {
  92         int     c;
  93         int     force = 0;
  94
  95         while ((c = getopt(argc, argv, "dm:np:v:qP:f")) != -1) {
  96                 switch (c) {
  97                 case 'f':
  98                         force = 1;
  99                         break;
 100                 case 'd':
 101                         opt_debug++;
 102                         break;
 103                 case 'm':
 104                         opt_max_retry = atoi(optarg) * 60;
 105                         break;
 106                 case 'n':
 107                         opt_update_state = 0;
 108                         break;
 109                 case 'p':
 110                         opt_srcport = atoi(optarg);
 111                         break;
 112                 case 'v':
 113                         opt_srcaddr = optarg;
 114                         break;
 115                 case 'q':
 116                         opt_quiet = 1;
 117                         break;
 118                 case 'P':
 119                         _SM_BASE_PATH = strdup(optarg);
 120                         _SM_STATE_PATH = malloc(strlen(optarg)+1+sizeof("state"));
 121                         _SM_DIR_PATH = malloc(strlen(optarg)+1+sizeof("sm"));
 122                         _SM_BAK_PATH = malloc(strlen(optarg)+1+sizeof("sm.bak"));
 123                         if (_SM_BASE_PATH == NULL ||
 124                             _SM_STATE_PATH == NULL ||
 125                             _SM_DIR_PATH == NULL ||
 126                             _SM_BAK_PATH == NULL) {
 127                                 nsm_log(LOG_WARNING, "unable to allocate memory");
 128                                 exit(1);
 129                         }
 130                         strcat(strcpy(_SM_STATE_PATH, _SM_BASE_PATH), "/state");
 131                         strcat(strcpy(_SM_DIR_PATH, _SM_BASE_PATH), "/sm");
 132                         strcat(strcpy(_SM_BAK_PATH, _SM_BASE_PATH), "/sm.bak");
 133                         break;
 134
 135                 default:
 136                         goto usage;
 137                 }
 138         }
 139
 140         if (optind < argc) {
 141 usage:          fprintf(stderr,
 142                         "Usage: sm-notify [-dfq] [-m max-retry-minutes] [-p srcport]\n"
 143                         "            [-P /path/to/state/directory] [-N my_host_name\n");
 144                 return 1;
 145         }
 146
 147         if (strcmp(_SM_BASE_PATH, BASEDIR) == 0) {
 148                 if (record_pid() == 0 && force == 0 && opt_update_state == 0)
 149                         /* already run, don't try again */
 150                         exit(0);
 151         }
 152
 153         if (opt_srcaddr) {
 154                 strncpy(nsm_hostname, opt_srcaddr, sizeof(nsm_hostname)-1);
 155         } else
 156         if (gethostname(nsm_hostname, sizeof(nsm_hostname)) < 0) {
 157                 perror("gethostname");
 158                 return 1;
 159         }
 160
 161         backup_hosts(_SM_DIR_PATH, _SM_BAK_PATH);
 162         get_hosts(_SM_BAK_PATH);
 163
 164         if (!opt_debug) {
 165                 if (!opt_quiet)
 166                         printf("Backgrounding to notify hosts...\n");
 167
 168                 openlog("sm-notify", LOG_PID, LOG_DAEMON);
 169                 log_syslog = 1;
 170
 171                 if (daemon(0, 0) < 0) {
 172                         nsm_log(LOG_WARNING, "unable to background: %s",
 173                                         strerror(errno));
 174                         return 1;
 175                 }
 176
 177                 close(0);
 178                 close(1);
 179                 close(2);
 180         }
 181
 182         /* Get and update the NSM state. This will call sync() */
 183         nsm_state = nsm_get_state(opt_update_state);
 184
 185         notify();
 186
 187         if (hosts) {
 188                 struct nsm_host *hp;
 189
 190                 while ((hp = hosts) != 0) {
 191                         hosts = hp->next;
 192                         nsm_log(LOG_NOTICE,
 193                                 "Unable to notify %s, giving up",
 194                                 hp->name);
 195                 }
 196                 return 1;
 197         }
 198
 199         return 0;
 200 }
 201
 202 /*
 203  * Notify hosts
 204  */
 205 void
 206 notify(void)
 207 {
 208         nsm_address local_addr;
 209         time_t  failtime = 0;
 210         int     sock = -1;
 211
 212         sock = socket(AF_INET, SOCK_DGRAM, 0);
 213         if (sock < 0) {
 214                 perror("socket");
 215                 exit(1);
 216         }
 217         fcntl(sock, F_SETFL, O_NONBLOCK);
 218
 219         memset(&local_addr, 0, sizeof(local_addr));
 220         local_addr.ss_family = AF_INET; /* Default to IPv4 */
 221
 222         /* Bind source IP if provided on command line */
 223         if (opt_srcaddr) {
 224                 if (!host_lookup(AF_INET, opt_srcaddr, &local_addr)) {
 225                         nsm_log(LOG_WARNING,
 226                                 "Not a valid hostname or address: \"%s\"\n",
 227                                 opt_srcaddr);
 228                         exit(1);
 229                 }
 230                 /* We know it's IPv4 at this point */
 231         }
 232
 233         /* Use source port if provided on the command line,
 234          * otherwise use bindresvport */
 235         if (opt_srcport) {
 236                 addr_set_port(&local_addr, opt_srcport);
 237                 if (bind(sock, (struct sockaddr *) &local_addr, sizeof(local_addr)) < 0) {
 238                         perror("bind");
 239                         exit(1);
 240                 }
 241         } else {
 242                 (void) bindresvport(sock, (struct sockaddr_in *) &local_addr);
 243         }
 244
 245         if (opt_max_retry)
 246                 failtime = time(NULL) + opt_max_retry;
 247
 248         drop_privs();
 249
 250         while (hosts) {
 251                 struct pollfd   pfd;
 252                 time_t          now = time(NULL);
 253                 unsigned int    sent = 0;
 254                 struct nsm_host *hp;
 255                 long            wait;
 256
 257                 if (failtime && now >= failtime)
 258                         break;
 259
 260                 while ((wait = hosts->send_next - now) <= 0) {
 261                         /* Never send more than 10 packets at once */
 262                         if (sent++ >= 10)
 263                                 break;
 264
 265                         /* Remove queue head */
 266                         hp = hosts;
 267                         hosts = hp->next;
 268
 269                         notify_host(sock, hp);
 270
 271                         /* Set the timeout for this call, using an
 272                            exponential timeout strategy */
 273                         wait = hp->timeout;
 274                         if ((hp->timeout <<= 1) > NSM_MAX_TIMEOUT)
 275                                 hp->timeout = NSM_MAX_TIMEOUT;
 276                         hp->send_next = now + wait;
 277                         hp->retries++;
 278
 279                         insert_host(hp);
 280                 }
 281
 282                 nsm_log(LOG_DEBUG, "Host %s due in %ld seconds",
 283                                 hosts->name, wait);
 284
 285                 pfd.fd = sock;
 286                 pfd.events = POLLIN;
 287
 288                 wait *= 1000;
 289                 if (wait < 100)
 290                         wait = 100;
 291                 if (poll(&pfd, 1, wait) != 1)
 292                         continue;
 293
 294                 recv_reply(sock);
 295         }
 296 }
 297
 298 /*
 299  * Send notification to a single host
 300  */
 301 void
 302 notify_host(int sock, struct nsm_host *host)
 303 {
 304         static unsigned int     xid = 0;
 305         nsm_address             dest;
 306         uint32_t                msgbuf[MAXMSGSIZE], *p;
 307         unsigned int            len;
 308
 309         if (!xid)
 310                 xid = getpid() + time(NULL);
 311         if (!host->xid)
 312                 host->xid = xid++;
 313
 314         memset(msgbuf, 0, sizeof(msgbuf));
 315         p = msgbuf;
 316         *p++ = htonl(host->xid);
 317         *p++ = 0;
 318         *p++ = htonl(2);
 319
 320         /* If we retransmitted 4 times, reset the port to force
 321          * a new portmap lookup (in case statd was restarted)
 322          */
 323         if (host->retries >= 4) {
 324                 addr_set_port(&host->addr, 0);
 325                 host->retries = 0;
 326         }
 327
 328         dest = host->addr;
 329         if (addr_get_port(&dest) == 0) {
 330                 /* Build a PMAP packet */
 331                 nsm_log(LOG_DEBUG, "Sending portmap query to %s", host->name);
 332
 333                 addr_set_port(&dest, 111);
 334                 *p++ = htonl(100000);
 335                 *p++ = htonl(2);
 336                 *p++ = htonl(3);
 337
 338                 /* Auth and verf */
 339                 *p++ = 0; *p++ = 0;
 340                 *p++ = 0; *p++ = 0;
 341
 342                 *p++ = htonl(NSM_PROGRAM);
 343                 *p++ = htonl(NSM_VERSION);
 344                 *p++ = htonl(IPPROTO_UDP);
 345                 *p++ = 0;
 346         } else {
 347                 /* Build an SM_NOTIFY packet */
 348                 nsm_log(LOG_DEBUG, "Sending SM_NOTIFY to %s", host->name);
 349
 350                 *p++ = htonl(NSM_PROGRAM);
 351                 *p++ = htonl(NSM_VERSION);
 352                 *p++ = htonl(NSM_NOTIFY);
 353
 354                 /* Auth and verf */
 355                 *p++ = 0; *p++ = 0;
 356                 *p++ = 0; *p++ = 0;
 357
 358                 /* state change */
 359                 len = strlen(nsm_hostname);
 360                 *p++ = htonl(len);
 361                 memcpy(p, nsm_hostname, len);
 362                 p += (len + 3) >> 2;
 363                 *p++ = htonl(nsm_state);
 364         }
 365         len = (p - msgbuf) << 2;
 366
 367         sendto(sock, msgbuf, len, 0, (struct sockaddr *) &dest, sizeof(dest));
 368 }
 369
 370 /*
 371  * Receive reply from remote host
 372  */
 373 void
 374 recv_reply(int sock)
 375 {
 376         struct nsm_host *hp;
 377         uint32_t        msgbuf[MAXMSGSIZE], *p, *end;
 378         uint32_t        xid;
 379         int             res;
 380
 381         res = recv(sock, msgbuf, sizeof(msgbuf), 0);
 382         if (res < 0)
 383                 return;
 384
 385         nsm_log(LOG_DEBUG, "Received packet...");
 386
 387         p = msgbuf;
 388         end = p + (res >> 2);
 389
 390         xid = ntohl(*p++);
 391         if (*p++ != htonl(1)    /* must be REPLY */
 392          || *p++ != htonl(0)    /* must be ACCEPTED */
 393          || *p++ != htonl(0)    /* must be NULL verifier */
 394          || *p++ != htonl(0)
 395          || *p++ != htonl(0))   /* must be SUCCESS */
 396                 return;
 397
 398         /* Before we look at the data, find the host struct for
 399            this reply */
 400         if ((hp = find_host(xid)) == NULL)
 401                 return;
 402
 403         if (addr_get_port(&hp->addr) == 0) {
 404                 /* This was a portmap request */
 405                 unsigned int    port;
 406
 407                 port = ntohl(*p++);
 408                 if (p > end)
 409                         goto fail;
 410
 411                 hp->send_next = time(NULL);
 412                 if (port == 0) {
 413                         /* No binding for statd. Delay the next
 414                          * portmap query for max timeout */
 415                         nsm_log(LOG_DEBUG, "No statd on %s", hp->name);
 416                         hp->timeout = NSM_MAX_TIMEOUT;
 417                         hp->send_next += NSM_MAX_TIMEOUT;
 418                 } else {
 419                         addr_set_port(&hp->addr, port);
 420                         if (hp->timeout >= NSM_MAX_TIMEOUT / 4)
 421                                 hp->timeout = NSM_MAX_TIMEOUT / 4;
 422                 }
 423                 hp->xid = 0;
 424         } else {
 425                 /* Successful NOTIFY call. Server returns void,
 426                  * so nothing we need to do here (except
 427                  * check that we didn't read past the end of the
 428                  * packet)
 429                  */
 430                 if (p <= end) {
 431                         nsm_log(LOG_DEBUG, "Host %s notified successfully", hp->name);
 432                         unlink(hp->path);
 433                         free(hp->name);
 434                         free(hp->path);
 435                         free(hp);
 436                         return;
 437                 }
 438         }
 439
 440 fail:   /* Re-insert the host */
 441         insert_host(hp);
 442 }
 443
 444 /*
 445  * Back up all hosts from the sm directory to sm.bak
 446  */
 447 static void
 448 backup_hosts(const char *dirname, const char *bakname)
 449 {
 450         struct dirent   *de;
 451         DIR             *dir;
 452
 453         if (!(dir = opendir(dirname))) {
 454                 perror(dirname);
 455                 return;
 456         }
 457
 458         while ((de = readdir(dir)) != NULL) {
 459                 char    src[1024], dst[1024];
 460
 461                 if (de->d_name[0] == '.')
 462                         continue;
 463
 464                 snprintf(src, sizeof(src), "%s/%s", dirname, de->d_name);
 465                 snprintf(dst, sizeof(dst), "%s/%s", bakname, de->d_name);
 466                 if (rename(src, dst) < 0) {
 467                         nsm_log(LOG_WARNING,
 468                                 "Failed to rename %s -> %s: %m",
 469                                 src, dst);
 470                 }
 471         }
 472         closedir(dir);
 473 }
 474
 475 /*
 476  * Get all entries from sm.bak and convert them to host names
 477  */
 478 static void
 479 get_hosts(const char *dirname)
 480 {
 481         struct nsm_host *host;
 482         struct dirent   *de;
 483         DIR             *dir;
 484
 485         if (!(dir = opendir(dirname))) {
 486                 perror(dirname);
 487                 return;
 488         }
 489
 490         host = NULL;
 491         while ((de = readdir(dir)) != NULL) {
 492                 struct stat     stb;
 493                 char            path[1024];
 494
 495                 if (de->d_name[0] == '.')
 496                         continue;
 497                 if (host == NULL)
 498                         host = calloc(1, sizeof(*host));
 499
 500                 snprintf(path, sizeof(path), "%s/%s", dirname, de->d_name);
 501                 if (!host_lookup(AF_UNSPEC, de->d_name, &host->addr)) {
 502                         nsm_log(LOG_WARNING,
 503                                 "%s doesn't seem to be a valid address, skipped",
 504                                 de->d_name);
 505                         unlink(path);
 506                         continue;
 507                 }
 508
 509                 if (stat(path, &stb) < 0)
 510                         continue;
 511                 host->last_used = stb.st_mtime;
 512                 host->timeout = NSM_TIMEOUT;
 513                 host->path = strdup(path);
 514                 host->name = strdup(de->d_name);
 515
 516                 insert_host(host);
 517                 host = NULL;
 518         }
 519         closedir(dir);
 520
 521         if (host)
 522                 free(host);
 523 }
 524
 525 /*
 526  * Insert host into sorted list
 527  */
 528 void
 529 insert_host(struct nsm_host *host)
 530 {
 531         struct nsm_host **where, *p;
 532
 533         where = &hosts;
 534         while ((p = *where) != 0) {
 535                 /* Sort in ascending order of timeout */
 536                 if (host->send_next < p->send_next)
 537                         break;
 538                 /* If we have the same timeout, put the
 539                  * most recently used host first.
 540                  * This makes sure that "recent" hosts
 541                  * get notified first.
 542                  */
 543                 if (host->send_next == p->send_next
 544                  && host->last_used > p->last_used)
 545                         break;
 546                 where = &p->next;
 547         }
 548
 549         host->next = *where;
 550         *where = host;
 551 }
 552
 553 /*
 554  * Find host given the XID
 555  */
 556 struct nsm_host *
 557 find_host(uint32_t xid)
 558 {
 559         struct nsm_host **where, *p;
 560
 561         where = &hosts;
 562         while ((p = *where) != 0) {
 563                 if (p->xid == xid) {
 564                         *where = p->next;
 565                         return p;
 566                 }
 567                 where = &p->next;
 568         }
 569         return NULL;
 570 }
 571
 572
 573 /*
 574  * Retrieve the current NSM state
 575  */
 576 unsigned int
 577 nsm_get_state(int update)
 578 {
 579         char            newfile[PATH_MAX];
 580         int             fd, state;
 581
 582         if ((fd = open(_SM_STATE_PATH, O_RDONLY)) < 0) {
 583                 if (!opt_quiet) {
 584                         nsm_log(LOG_WARNING, "%s: %m", _SM_STATE_PATH);
 585                         nsm_log(LOG_WARNING, "Creating %s, set initial state 1",
 586                                 _SM_STATE_PATH);
 587                 }
 588                 state = 1;
 589                 update = 1;
 590         } else {
 591                 if (read(fd, &state, sizeof(state)) != sizeof(state)) {
 592                         nsm_log(LOG_WARNING,
 593                                 "%s: bad file size, setting state = 1",
 594                                 _SM_STATE_PATH);
 595                         state = 1;
 596                         update = 1;
 597                 } else {
 598                         if (!(state & 1))
 599                                 state += 1;
 600                 }
 601                 close(fd);
 602         }
 603
 604         if (update) {
 605                 state += 2;
 606                 snprintf(newfile, sizeof(newfile),
 607                                 "%s.new", _SM_STATE_PATH);
 608                 if ((fd = open(newfile, O_CREAT|O_WRONLY, 0644)) < 0) {
 609                         nsm_log(LOG_WARNING, "Cannot create %s: %m", newfile);
 610                         exit(1);
 611                 }
 612                 if (write(fd, &state, sizeof(state)) != sizeof(state)) {
 613                         nsm_log(LOG_WARNING,
 614                                 "Failed to write state to %s", newfile);
 615                         exit(1);
 616                 }
 617                 close(fd);
 618                 if (rename(newfile, _SM_STATE_PATH) < 0) {
 619                         nsm_log(LOG_WARNING,
 620                                 "Cannot create %s: %m", _SM_STATE_PATH);
 621                         exit(1);
 622                 }
 623                 sync();
 624         }
 625
 626         return state;
 627 }
 628
 629 /*
 630  * Address handling utilities
 631  */
 632
 633 int
 634 addr_get_port(nsm_address *addr)
 635 {
 636         switch (((struct sockaddr *) addr)->sa_family) {
 637         case AF_INET:
 638                 return ntohs(((struct sockaddr_in *) addr)->sin_port);
 639         case AF_INET6:
 640                 return ntohs(((struct sockaddr_in6 *) addr)->sin6_port);
 641         }
 642         return 0;
 643 }
 644
 645 static void
 646 addr_set_port(nsm_address *addr, int port)
 647 {
 648         switch (((struct sockaddr *) addr)->sa_family) {
 649         case AF_INET:
 650                 ((struct sockaddr_in *) addr)->sin_port = htons(port);
 651                 break;
 652         case AF_INET6:
 653                 ((struct sockaddr_in6 *) addr)->sin6_port = htons(port);
 654         }
 655 }
 656
 657 static int
 658 host_lookup(int af, const char *name, nsm_address *addr)
 659 {
 660         struct addrinfo hints, *ai;
 661         int okay = 0;
 662
 663         memset(&hints, 0, sizeof(hints));
 664         hints.ai_family = af;
 665
 666         if (getaddrinfo(name, NULL, &hints, &ai) != 0)
 667                 return 0;
 668
 669         if (ai->ai_addrlen < sizeof(*addr)) {
 670                 memcpy(addr, ai->ai_addr, ai->ai_addrlen);
 671                 okay = 1;
 672         }
 673
 674         freeaddrinfo(ai);
 675         return okay;
 676 }
 677
 678 /*
 679  * Log a message
 680  */
 681 void
 682 nsm_log(int fac, const char *fmt, ...)
 683 {
 684         va_list ap;
 685
 686         if (fac == LOG_DEBUG && !opt_debug)
 687                 return;
 688
 689         va_start(ap, fmt);
 690         if (log_syslog)
 691                 vsyslog(fac, fmt, ap);
 692         else {
 693                 vfprintf(stderr, fmt, ap);
 694                 fputs("\n", stderr);
 695         }
 696         va_end(ap);
 697 }
 698
 699 /*
 700  * Record pid in /var/run/sm-notify.pid
 701  * This file should remain until a reboot, even if the
 702  * program exits.
 703  * If file already exists, fail.
 704  */
 705 static int record_pid()
 706 {
 707         char pid[20];
 708         int fd;
 709
 710         snprintf(pid, 20, "%d\n", getpid());
 711         fd = open("/var/run/sm-notify.pid", O_CREAT|O_EXCL|O_WRONLY, 0600);
 712         if (!fd)
 713                 return 0;
 714         write(fd, pid, strlen(pid));
 715         close(fd);
 716         return 1;
 717 }
 718
 719 /* Drop privileges to match owner of state-directory
 720  * (in case a reply triggers some unknown bug).
 721  */
 722 static void drop_privs(void)
 723 {
 724         struct stat st;
 725
 726         if (stat(_SM_DIR_PATH, &st) == -1 &&
 727             stat(_SM_BASE_PATH, &st) == -1) {
 728                 st.st_uid = 0;
 729                 st.st_gid = 0;
 730         }
 731
 732         if (st.st_uid == 0) {
 733                 nsm_log(LOG_WARNING,
 734                         "sm-notify running as root. chown %s to choose different user\n",
 735                     _SM_DIR_PATH);
 736                 return;
 737         }
 738
 739         setgroups(0, NULL);
 740         if (setgid(st.st_gid) == -1
 741             || setuid(st.st_uid) == -1) {
 742                 nsm_log(LOG_ERR, "Fail to drop privileges");
 743                 exit(1);
 744         }
 745 }