usr.sbin/rpc.statd/statd.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-4-Clause
   3  *
   4  * Copyright (c) 1995
   5  *      A.R. Gordon (andrew.gordon@net-tel.co.uk).  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. All advertising materials mentioning features or use of this software
  16  *    must display the following acknowledgement:
  17  *      This product includes software developed for the FreeBSD project
  18  * 4. Neither the name of the author nor the names of any co-contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY ANDREW GORDON AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  */
  35
  36 /* main() function for status monitor daemon.  Some of the code in this */
  37 /* file was generated by running rpcgen /usr/include/rpcsvc/sm_inter.x  */
  38 /* The actual program logic is in the file procs.c                      */
  39
  40 #include <sys/cdefs.h>
  41 __FBSDID("$FreeBSD$");
  42
  43 #include <err.h>
  44 #include <errno.h>
  45 #include <stdio.h>
  46 #include <stdlib.h>
  47 #include <rpc/rpc.h>
  48 #include <rpc/rpc_com.h>
  49 #include <string.h>
  50 #include <syslog.h>
  51 #include <sys/types.h>
  52 #include <sys/socket.h>
  53 #include <sys/wait.h>
  54 #include <netinet/in.h>
  55 #include <arpa/inet.h>
  56 #include <netdb.h>
  57 #include <signal.h>
  58 #include <unistd.h>
  59 #include "statd.h"
  60
  61 #define GETPORT_MAXTRY  20      /* Max tries to get a port # */
  62
  63 int debug = 0;          /* Controls syslog() calls for debug messages   */
  64
  65 static char **hosts, *svcport_str = NULL;
  66 static int nhosts = 0;
  67 static int xcreated = 0;
  68 static int      mallocd_svcport = 0;
  69 static int      *sock_fd;
  70 static int      sock_fdcnt;
  71 static int      sock_fdpos;
  72
  73 static int      create_service(struct netconfig *nconf);
  74 static void     complete_service(struct netconfig *nconf, char *port_str);
  75 static void     clearout_service(void);
  76 static void handle_sigchld(int sig);
  77 void out_of_mem(void) __dead2;
  78
  79 static void usage(void) __dead2;
  80
  81 int
  82 main(int argc, char **argv)
  83 {
  84   struct sigaction sa;
  85   struct netconfig *nconf;
  86   void *nc_handle;
  87   in_port_t svcport;
  88   int ch, i, s;
  89   char *endptr;
  90   char **hosts_bak;
  91   int have_v6 = 1;
  92   int foreground = 0;
  93   int maxrec = RPC_MAXDATASIZE;
  94   int attempt_cnt, port_len, port_pos, ret;
  95   char **port_list;
  96
  97   while ((ch = getopt(argc, argv, "dFh:p:")) != -1)
  98     switch (ch) {
  99     case 'd':
 100       debug = 1;
 101       break;
 102     case 'F':
 103       foreground = 1;
 104       break;
 105     case 'h':
 106       ++nhosts;
 107       hosts_bak = hosts;
 108       hosts_bak = realloc(hosts, nhosts * sizeof(char *));
 109       if (hosts_bak == NULL) {
 110               if (hosts != NULL) {
 111                       for (i = 0; i < nhosts; i++)
 112                               free(hosts[i]);
 113                       free(hosts);
 114                       out_of_mem();
 115               }
 116       }
 117       hosts = hosts_bak;
 118       hosts[nhosts - 1] = strdup(optarg);
 119       if (hosts[nhosts - 1] == NULL) {
 120               for (i = 0; i < (nhosts - 1); i++)
 121                       free(hosts[i]);
 122               free(hosts);
 123               out_of_mem();
 124       }
 125       break;
 126     case 'p':
 127       endptr = NULL;
 128       svcport = (in_port_t)strtoul(optarg, &endptr, 10);
 129       if (endptr == NULL || *endptr != '\0' || svcport == 0 ||
 130           svcport >= IPPORT_MAX)
 131         usage();
 132
 133       svcport_str = strdup(optarg);
 134       break;
 135     default:
 136       usage();
 137     }
 138   argc -= optind;
 139   argv += optind;
 140
 141   (void)rpcb_unset(SM_PROG, SM_VERS, NULL);
 142
 143   /*
 144    * Check if IPv6 support is present.
 145    */
 146   s = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP);
 147   if (s < 0)
 148       have_v6 = 0;
 149   else
 150       close(s);
 151
 152   rpc_control(RPC_SVC_CONNMAXREC_SET, &maxrec);
 153
 154   /*
 155    * If no hosts were specified, add a wildcard entry to bind to
 156    * INADDR_ANY. Otherwise make sure 127.0.0.1 and ::1 are added to the
 157    * list.
 158    */
 159   if (nhosts == 0) {
 160           hosts = malloc(sizeof(char *));
 161           if (hosts == NULL)
 162                   out_of_mem();
 163
 164           hosts[0] = strdup("*");
 165           nhosts = 1;
 166   } else {
 167           hosts_bak = hosts;
 168           if (have_v6) {
 169                   hosts_bak = realloc(hosts, (nhosts + 2) *
 170                       sizeof(char *));
 171                   if (hosts_bak == NULL) {
 172                           for (i = 0; i < nhosts; i++)
 173                                   free(hosts[i]);
 174                           free(hosts);
 175                           out_of_mem();
 176                   } else
 177                           hosts = hosts_bak;
 178
 179                   nhosts += 2;
 180                   hosts[nhosts - 2] = strdup("::1");
 181           } else {
 182                   hosts_bak = realloc(hosts, (nhosts + 1) * sizeof(char *));
 183                   if (hosts_bak == NULL) {
 184                           for (i = 0; i < nhosts; i++)
 185                                   free(hosts[i]);
 186
 187                           free(hosts);
 188                           out_of_mem();
 189                   } else {
 190                           nhosts += 1;
 191                           hosts = hosts_bak;
 192                   }
 193           }
 194           hosts[nhosts - 1] = strdup("127.0.0.1");
 195   }
 196
 197   attempt_cnt = 1;
 198   sock_fdcnt = 0;
 199   sock_fd = NULL;
 200   port_list = NULL;
 201   port_len = 0;
 202   nc_handle = setnetconfig();
 203   while ((nconf = getnetconfig(nc_handle))) {
 204           /* We want to listen only on udp6, tcp6, udp, tcp transports */
 205           if (nconf->nc_flag & NC_VISIBLE) {
 206                   /* Skip if there's no IPv6 support */
 207                   if (have_v6 == 0 && strcmp(nconf->nc_protofmly, "inet6") == 0) {
 208               /* DO NOTHING */
 209                   } else {
 210                         ret = create_service(nconf);
 211                         if (ret == 1)
 212                                 /* Ignore this call */
 213                                 continue;
 214                         if (ret < 0) {
 215                                 /*
 216                                  * Failed to bind port, so close off
 217                                  * all sockets created and try again
 218                                  * if the port# was dynamically
 219                                  * assigned via bind(2).
 220                                  */
 221                                 clearout_service();
 222                                 if (mallocd_svcport != 0 &&
 223                                     attempt_cnt < GETPORT_MAXTRY) {
 224                                         free(svcport_str);
 225                                         svcport_str = NULL;
 226                                         mallocd_svcport = 0;
 227                                 } else {
 228                                         errno = EADDRINUSE;
 229                                         syslog(LOG_ERR,
 230                                             "bindresvport_sa: %m");
 231                                         exit(1);
 232                                 }
 233
 234                                 /* Start over at the first service. */
 235                                 free(sock_fd);
 236                                 sock_fdcnt = 0;
 237                                 sock_fd = NULL;
 238                                 nc_handle = setnetconfig();
 239                                 attempt_cnt++;
 240                         } else if (mallocd_svcport != 0 &&
 241                             attempt_cnt == GETPORT_MAXTRY) {
 242                                 /*
 243                                  * For the last attempt, allow
 244                                  * different port #s for each nconf
 245                                  * by saving the svcport_str and
 246                                  * setting it back to NULL.
 247                                  */
 248                                 port_list = realloc(port_list,
 249                                     (port_len + 1) * sizeof(char *));
 250                                 if (port_list == NULL)
 251                                         out_of_mem();
 252                                 port_list[port_len++] = svcport_str;
 253                                 svcport_str = NULL;
 254                                 mallocd_svcport = 0;
 255                         }
 256                   }
 257           }
 258   }
 259
 260   /*
 261    * Successfully bound the ports, so call complete_service() to
 262    * do the rest of the setup on the service(s).
 263    */
 264   sock_fdpos = 0;
 265   port_pos = 0;
 266   nc_handle = setnetconfig();
 267   while ((nconf = getnetconfig(nc_handle))) {
 268           /* We want to listen only on udp6, tcp6, udp, tcp transports */
 269           if (nconf->nc_flag & NC_VISIBLE) {
 270                   /* Skip if there's no IPv6 support */
 271                   if (have_v6 == 0 && strcmp(nconf->nc_protofmly, "inet6") == 0) {
 272               /* DO NOTHING */
 273                   } else if (port_list != NULL) {
 274                         if (port_pos >= port_len) {
 275                                 syslog(LOG_ERR, "too many port#s");
 276                                 exit(1);
 277                         }
 278                         complete_service(nconf, port_list[port_pos++]);
 279                   } else
 280                         complete_service(nconf, svcport_str);
 281           }
 282   }
 283   endnetconfig(nc_handle);
 284   free(sock_fd);
 285   if (port_list != NULL) {
 286         for (port_pos = 0; port_pos < port_len; port_pos++)
 287                 free(port_list[port_pos]);
 288         free(port_list);
 289   }
 290
 291   init_file("/var/db/statd.status");
 292
 293   /* Note that it is NOT sensible to run this program from inetd - the  */
 294   /* protocol assumes that it will run immediately at boot time.        */
 295   if ((foreground == 0) && daemon(0, 0) < 0) {
 296         err(1, "cannot fork");
 297         /* NOTREACHED */
 298   }
 299
 300   openlog("rpc.statd", 0, LOG_DAEMON);
 301   if (debug) syslog(LOG_INFO, "Starting - debug enabled");
 302   else syslog(LOG_INFO, "Starting");
 303
 304   /* Install signal handler to collect exit status of child processes   */
 305   sa.sa_handler = handle_sigchld;
 306   sigemptyset(&sa.sa_mask);
 307   sigaddset(&sa.sa_mask, SIGCHLD);
 308   sa.sa_flags = SA_RESTART;
 309   sigaction(SIGCHLD, &sa, NULL);
 310
 311   /* Initialisation now complete - start operating                      */
 312   notify_hosts();       /* Forks a process (if necessary) to do the     */
 313                         /* SM_NOTIFY calls, which may be slow.          */
 314
 315   svc_run();    /* Should never return                                  */
 316   exit(1);
 317 }
 318
 319 /*
 320  * This routine creates and binds sockets on the appropriate
 321  * addresses. It gets called one time for each transport.
 322  * It returns 0 upon success, 1 for ingore the call and -1 to indicate
 323  * bind failed with EADDRINUSE.
 324  * Any file descriptors that have been created are stored in sock_fd and
 325  * the total count of them is maintained in sock_fdcnt.
 326  */
 327 static int
 328 create_service(struct netconfig *nconf)
 329 {
 330         struct addrinfo hints, *res = NULL;
 331         struct sockaddr_in *sin;
 332         struct sockaddr_in6 *sin6;
 333         struct __rpc_sockinfo si;
 334         int aicode;
 335         int fd;
 336         int nhostsbak;
 337         int r;
 338         u_int32_t host_addr[4];  /* IPv4 or IPv6 */
 339         int mallocd_res;
 340
 341         if ((nconf->nc_semantics != NC_TPI_CLTS) &&
 342             (nconf->nc_semantics != NC_TPI_COTS) &&
 343             (nconf->nc_semantics != NC_TPI_COTS_ORD))
 344                 return (1);     /* not my type */
 345
 346         /*
 347          * XXX - using RPC library internal functions.
 348          */
 349         if (!__rpc_nconf2sockinfo(nconf, &si)) {
 350                 syslog(LOG_ERR, "cannot get information for %s",
 351                     nconf->nc_netid);
 352                 return (1);
 353         }
 354
 355         /* Get rpc.statd's address on this transport */
 356         memset(&hints, 0, sizeof hints);
 357         hints.ai_family = si.si_af;
 358         hints.ai_socktype = si.si_socktype;
 359         hints.ai_protocol = si.si_proto;
 360
 361         /*
 362          * Bind to specific IPs if asked to
 363          */
 364         nhostsbak = nhosts;
 365         while (nhostsbak > 0) {
 366                 --nhostsbak;
 367                 sock_fd = realloc(sock_fd, (sock_fdcnt + 1) * sizeof(int));
 368                 if (sock_fd == NULL)
 369                         out_of_mem();
 370                 sock_fd[sock_fdcnt++] = -1;     /* Set invalid for now. */
 371                 mallocd_res = 0;
 372                 hints.ai_flags = AI_PASSIVE;
 373
 374                 /*
 375                  * XXX - using RPC library internal functions.
 376                  */
 377                 if ((fd = __rpc_nconf2fd(nconf)) < 0) {
 378                         syslog(LOG_ERR, "cannot create socket for %s",
 379                             nconf->nc_netid);
 380                         continue;
 381                 }
 382                 switch (hints.ai_family) {
 383                 case AF_INET:
 384                         if (inet_pton(AF_INET, hosts[nhostsbak],
 385                             host_addr) == 1) {
 386                                 hints.ai_flags |= AI_NUMERICHOST;
 387                         } else {
 388                                 /*
 389                                  * Skip if we have an AF_INET6 address.
 390                                  */
 391                                 if (inet_pton(AF_INET6, hosts[nhostsbak],
 392                                     host_addr) == 1) {
 393                                         close(fd);
 394                                         continue;
 395                                 }
 396                         }
 397                         break;
 398                 case AF_INET6:
 399                         if (inet_pton(AF_INET6, hosts[nhostsbak],
 400                             host_addr) == 1) {
 401                                 hints.ai_flags |= AI_NUMERICHOST;
 402                         } else {
 403                                 /*
 404                                  * Skip if we have an AF_INET address.
 405                                  */
 406                                 if (inet_pton(AF_INET, hosts[nhostsbak],
 407                                     host_addr) == 1) {
 408                                         close(fd);
 409                                         continue;
 410                                 }
 411                         }
 412                         break;
 413                 default:
 414                         break;
 415                 }
 416
 417                 /*
 418                  * If no hosts were specified, just bind to INADDR_ANY
 419                  */
 420                 if (strcmp("*", hosts[nhostsbak]) == 0) {
 421                         if (svcport_str == NULL) {
 422                                 res = malloc(sizeof(struct addrinfo));
 423                                 if (res == NULL)
 424                                         out_of_mem();
 425                                 mallocd_res = 1;
 426                                 res->ai_flags = hints.ai_flags;
 427                                 res->ai_family = hints.ai_family;
 428                                 res->ai_protocol = hints.ai_protocol;
 429                                 switch (res->ai_family) {
 430                                 case AF_INET:
 431                                         sin = malloc(sizeof(struct sockaddr_in));
 432                                         if (sin == NULL)
 433                                                 out_of_mem();
 434                                         sin->sin_family = AF_INET;
 435                                         sin->sin_port = htons(0);
 436                                         sin->sin_addr.s_addr = htonl(INADDR_ANY);
 437                                         res->ai_addr = (struct sockaddr*) sin;
 438                                         res->ai_addrlen = (socklen_t)
 439                                             sizeof(struct sockaddr_in);
 440                                         break;
 441                                 case AF_INET6:
 442                                         sin6 = malloc(sizeof(struct sockaddr_in6));
 443                                         if (sin6 == NULL)
 444                                                 out_of_mem();
 445                                         sin6->sin6_family = AF_INET6;
 446                                         sin6->sin6_port = htons(0);
 447                                         sin6->sin6_addr = in6addr_any;
 448                                         res->ai_addr = (struct sockaddr*) sin6;
 449                                         res->ai_addrlen = (socklen_t)
 450                                             sizeof(struct sockaddr_in6);
 451                                         break;
 452                                 default:
 453                                         syslog(LOG_ERR, "bad addr fam %d",
 454                                             res->ai_family);
 455                                         exit(1);
 456                                 }
 457                         } else {
 458                                 if ((aicode = getaddrinfo(NULL, svcport_str,
 459                                     &hints, &res)) != 0) {
 460                                         syslog(LOG_ERR,
 461                                             "cannot get local address for %s: %s",
 462                                             nconf->nc_netid,
 463                                             gai_strerror(aicode));
 464                                         close(fd);
 465                                         continue;
 466                                 }
 467                         }
 468                 } else {
 469                         if ((aicode = getaddrinfo(hosts[nhostsbak], svcport_str,
 470                             &hints, &res)) != 0) {
 471                                 syslog(LOG_ERR,
 472                                     "cannot get local address for %s: %s",
 473                                     nconf->nc_netid, gai_strerror(aicode));
 474                                 close(fd);
 475                                 continue;
 476                         }
 477                 }
 478
 479                 /* Store the fd. */
 480                 sock_fd[sock_fdcnt - 1] = fd;
 481
 482                 /* Now, attempt the bind. */
 483                 r = bindresvport_sa(fd, res->ai_addr);
 484                 if (r != 0) {
 485                         if (errno == EADDRINUSE && mallocd_svcport != 0) {
 486                                 if (mallocd_res != 0) {
 487                                         free(res->ai_addr);
 488                                         free(res);
 489                                 } else
 490                                         freeaddrinfo(res);
 491                                 return (-1);
 492                         }
 493                         syslog(LOG_ERR, "bindresvport_sa: %m");
 494                         exit(1);
 495                 }
 496
 497                 if (svcport_str == NULL) {
 498                         svcport_str = malloc(NI_MAXSERV * sizeof(char));
 499                         if (svcport_str == NULL)
 500                                 out_of_mem();
 501                         mallocd_svcport = 1;
 502
 503                         if (getnameinfo(res->ai_addr,
 504                             res->ai_addr->sa_len, NULL, NI_MAXHOST,
 505                             svcport_str, NI_MAXSERV * sizeof(char),
 506                             NI_NUMERICHOST | NI_NUMERICSERV))
 507                                 errx(1, "Cannot get port number");
 508                 }
 509                 if (mallocd_res != 0) {
 510                         free(res->ai_addr);
 511                         free(res);
 512                 } else
 513                         freeaddrinfo(res);
 514                 res = NULL;
 515         }
 516         return (0);
 517 }
 518
 519 /*
 520  * Called after all the create_service() calls have succeeded, to complete
 521  * the setup and registration.
 522  */
 523 static void
 524 complete_service(struct netconfig *nconf, char *port_str)
 525 {
 526         struct addrinfo hints, *res = NULL;
 527         struct __rpc_sockinfo si;
 528         struct netbuf servaddr;
 529         SVCXPRT *transp = NULL;
 530         int aicode, fd, nhostsbak;
 531         int registered = 0;
 532
 533         if ((nconf->nc_semantics != NC_TPI_CLTS) &&
 534             (nconf->nc_semantics != NC_TPI_COTS) &&
 535             (nconf->nc_semantics != NC_TPI_COTS_ORD))
 536                 return; /* not my type */
 537
 538         /*
 539          * XXX - using RPC library internal functions.
 540          */
 541         if (!__rpc_nconf2sockinfo(nconf, &si)) {
 542                 syslog(LOG_ERR, "cannot get information for %s",
 543                     nconf->nc_netid);
 544                 return;
 545         }
 546
 547         nhostsbak = nhosts;
 548         while (nhostsbak > 0) {
 549                 --nhostsbak;
 550                 if (sock_fdpos >= sock_fdcnt) {
 551                         /* Should never happen. */
 552                         syslog(LOG_ERR, "Ran out of socket fd's");
 553                         return;
 554                 }
 555                 fd = sock_fd[sock_fdpos++];
 556                 if (fd < 0)
 557                         continue;
 558
 559                 if (nconf->nc_semantics != NC_TPI_CLTS)
 560                         listen(fd, SOMAXCONN);
 561
 562                 transp = svc_tli_create(fd, nconf, NULL,
 563                 RPC_MAXDATASIZE, RPC_MAXDATASIZE);
 564
 565                 if (transp != (SVCXPRT *) NULL) {
 566                         if (!svc_register(transp, SM_PROG, SM_VERS,
 567                             sm_prog_1, 0)) {
 568                                 syslog(LOG_ERR, "can't register on %s",
 569                                     nconf->nc_netid);
 570                         } else {
 571                                 if (!svc_reg(transp, SM_PROG, SM_VERS,
 572                                     sm_prog_1, NULL))
 573                                         syslog(LOG_ERR,
 574                                             "can't register %s SM_PROG service",
 575                                             nconf->nc_netid);
 576                         }
 577                 } else
 578                         syslog(LOG_WARNING, "can't create %s services",
 579                             nconf->nc_netid);
 580
 581                 if (registered == 0) {
 582                         registered = 1;
 583                         memset(&hints, 0, sizeof hints);
 584                         hints.ai_flags = AI_PASSIVE;
 585                         hints.ai_family = si.si_af;
 586                         hints.ai_socktype = si.si_socktype;
 587                         hints.ai_protocol = si.si_proto;
 588
 589
 590                         if ((aicode = getaddrinfo(NULL, port_str, &hints,
 591                             &res)) != 0) {
 592                                 syslog(LOG_ERR, "cannot get local address: %s",
 593                                     gai_strerror(aicode));
 594                                 exit(1);
 595                         }
 596
 597                         servaddr.buf = malloc(res->ai_addrlen);
 598                         memcpy(servaddr.buf, res->ai_addr, res->ai_addrlen);
 599                         servaddr.len = res->ai_addrlen;
 600
 601                         rpcb_set(SM_PROG, SM_VERS, nconf, &servaddr);
 602
 603                         xcreated++;
 604                         freeaddrinfo(res);
 605                 }
 606         } /* end while */
 607 }
 608
 609 /*
 610  * Clear out sockets after a failure to bind one of them, so that the
 611  * cycle of socket creation/binding can start anew.
 612  */
 613 static void
 614 clearout_service(void)
 615 {
 616         int i;
 617
 618         for (i = 0; i < sock_fdcnt; i++) {
 619                 if (sock_fd[i] >= 0) {
 620                         shutdown(sock_fd[i], SHUT_RDWR);
 621                         close(sock_fd[i]);
 622                 }
 623         }
 624 }
 625
 626 static void
 627 usage(void)
 628 {
 629       fprintf(stderr, "usage: rpc.statd [-d] [-F] [-h <bindip>] [-p <port>]\n");
 630       exit(1);
 631 }
 632
 633 /* handle_sigchld ---------------------------------------------------------- */
 634 /*
 635    Purpose:     Catch SIGCHLD and collect process status
 636    Retruns:     Nothing.
 637    Notes:       No special action required, other than to collect the
 638                 process status and hence allow the child to die:
 639                 we only use child processes for asynchronous transmission
 640                 of SM_NOTIFY to other systems, so it is normal for the
 641                 children to exit when they have done their work.
 642 */
 643
 644 static void handle_sigchld(int sig __unused)
 645 {
 646   int pid, status;
 647   pid = wait4(-1, &status, WNOHANG, (struct rusage*)0);
 648   if (!pid) syslog(LOG_ERR, "Phantom SIGCHLD??");
 649   else if (status == 0)
 650   {
 651     if (debug) syslog(LOG_DEBUG, "Child %d exited OK", pid);
 652   }
 653   else syslog(LOG_ERR, "Child %d failed with status %d", pid,
 654     WEXITSTATUS(status));
 655 }
 656
 657 /*
 658  * Out of memory, fatal
 659  */
 660 void
 661 out_of_mem(void)
 662 {
 663
 664         syslog(LOG_ERR, "out of memory");
 665         exit(2);
 666 }