cups/http-addrlist.c

   1 /*
   2  * "$Id$"
   3  *
   4  *   HTTP address list routines for CUPS.
   5  *
   6  *   Copyright 2007-2013 by Apple Inc.
   7  *   Copyright 1997-2007 by Easy Software Products, all rights reserved.
   8  *
   9  *   These coded instructions, statements, and computer programs are the
  10  *   property of Apple Inc. and are protected by Federal copyright
  11  *   law.  Distribution and use rights are outlined in the file "LICENSE.txt"
  12  *   which should have been included with this file.  If this file is
  13  *   file is missing or damaged, see the license at "http://www.cups.org/".
  14  *
  15  * Contents:
  16  *
  17  *   httpAddrConnect()  - Connect to any of the addresses in the list.
  18  *   httpAddrConnect2() - Connect to any of the addresses in the list with a
  19  *                        timeout and optional cancel.
  20  *   httpAddrCopyList() - Copy an address list.
  21  *   httpAddrFreeList() - Free an address list.
  22  *   httpAddrGetList()  - Get a list of addresses for a hostname.
  23  */
  24
  25 /*
  26  * Include necessary headers...
  27  */
  28
  29 #include "cups-private.h"
  30 #ifdef HAVE_RESOLV_H
  31 #  include <resolv.h>
  32 #endif /* HAVE_RESOLV_H */
  33 #ifdef HAVE_POLL
  34 #  include <poll.h>
  35 #endif /* HAVE_POLL */
  36 #ifndef WIN32
  37 #  include <fcntl.h>
  38 #endif /* WIN32 */
  39
  40
  41 /*
  42  * 'httpAddrConnect()' - Connect to any of the addresses in the list.
  43  *
  44  * @since CUPS 1.2/OS X 10.5@
  45  */
  46
  47 http_addrlist_t *                       /* O - Connected address or NULL on failure */
  48 httpAddrConnect(
  49     http_addrlist_t *addrlist,          /* I - List of potential addresses */
  50     int             *sock)              /* O - Socket */
  51 {
  52   DEBUG_printf(("httpAddrConnect(addrlist=%p, sock=%p)", addrlist, sock));
  53
  54   return (httpAddrConnect2(addrlist, sock, 30000, NULL));
  55 }
  56
  57
  58 /*
  59  * 'httpAddrConnect2()' - Connect to any of the addresses in the list with a
  60  *                        timeout and optional cancel.
  61  *
  62  * @since CUPS 1.7/OS X 10.9@
  63  */
  64
  65 http_addrlist_t *                       /* O - Connected address or NULL on failure */
  66 httpAddrConnect2(
  67     http_addrlist_t *addrlist,          /* I - List of potential addresses */
  68     int             *sock,              /* O - Socket */
  69     int             msec,               /* I - Timeout in milliseconds */
  70     int             *cancel)            /* I - Pointer to "cancel" variable */
  71 {
  72   int                   val;            /* Socket option value */
  73 #ifdef O_NONBLOCK
  74   socklen_t             len;            /* Length of value */
  75   http_addr_t           peer;           /* Peer address */
  76   int                   flags,          /* Socket flags */
  77                         remaining;      /* Remaining timeout */
  78 #  ifdef HAVE_POLL
  79   struct pollfd         pfd;            /* Polled file descriptor */
  80 #  else
  81   fd_set                input_set,      /* select() input set */
  82                         output_set;     /* select() output set */
  83   struct timeval        timeout;        /* Timeout */
  84 #  endif /* HAVE_POLL */
  85   int                   nfds;           /* Result from select()/poll() */
  86 #endif /* O_NONBLOCK */
  87 #ifdef DEBUG
  88   char                  temp[256];      /* Temporary address string */
  89 #endif /* DEBUG */
  90
  91
  92   DEBUG_printf(("httpAddrConnect2(addrlist=%p, sock=%p, msec=%d, cancel=%p)",
  93                 addrlist, sock, msec, cancel));
  94
  95   if (!sock)
  96   {
  97     errno = EINVAL;
  98     _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
  99     return (NULL);
 100   }
 101
 102   if (cancel && *cancel)
 103     return (NULL);
 104
 105   if (msec <= 0 || getenv("CUPS_DISABLE_ASYNC_CONNECT"))
 106     msec = INT_MAX;
 107
 108  /*
 109   * Loop through each address until we connect or run out of addresses...
 110   */
 111
 112   while (addrlist)
 113   {
 114     if (cancel && *cancel)
 115       return (NULL);
 116
 117    /*
 118     * Create the socket...
 119     */
 120
 121     DEBUG_printf(("2httpAddrConnect2: Trying %s:%d...",
 122                   httpAddrString(&(addrlist->addr), temp, sizeof(temp)),
 123                   httpAddrPort(&(addrlist->addr))));
 124
 125     if ((*sock = (int)socket(httpAddrFamily(&(addrlist->addr)), SOCK_STREAM,
 126                              0)) < 0)
 127     {
 128      /*
 129       * Don't abort yet, as this could just be an issue with the local
 130       * system not being configured with IPv4/IPv6/domain socket enabled...
 131       */
 132
 133       addrlist = addrlist->next;
 134       continue;
 135     }
 136
 137    /*
 138     * Set options...
 139     */
 140
 141     val = 1;
 142     setsockopt(*sock, SOL_SOCKET, SO_REUSEADDR, CUPS_SOCAST &val, sizeof(val));
 143
 144 #ifdef SO_REUSEPORT
 145     val = 1;
 146     setsockopt(*sock, SOL_SOCKET, SO_REUSEPORT, CUPS_SOCAST &val, sizeof(val));
 147 #endif /* SO_REUSEPORT */
 148
 149 #ifdef SO_NOSIGPIPE
 150     val = 1;
 151     setsockopt(*sock, SOL_SOCKET, SO_NOSIGPIPE, CUPS_SOCAST &val, sizeof(val));
 152 #endif /* SO_NOSIGPIPE */
 153
 154    /*
 155     * Using TCP_NODELAY improves responsiveness, especially on systems
 156     * with a slow loopback interface...
 157     */
 158
 159     val = 1;
 160     setsockopt(*sock, IPPROTO_TCP, TCP_NODELAY, CUPS_SOCAST &val, sizeof(val));
 161
 162 #ifdef FD_CLOEXEC
 163    /*
 164     * Close this socket when starting another process...
 165     */
 166
 167     fcntl(*sock, F_SETFD, FD_CLOEXEC);
 168 #endif /* FD_CLOEXEC */
 169
 170 #ifdef O_NONBLOCK
 171    /*
 172     * Do an asynchronous connect by setting the socket non-blocking...
 173     */
 174
 175     DEBUG_printf(("httpAddrConnect2: Setting non-blocking connect()"));
 176
 177     flags = fcntl(*sock, F_GETFL, 0);
 178     if (msec != INT_MAX)
 179     {
 180       DEBUG_puts("httpAddrConnect2: Setting non-blocking connect()");
 181
 182       fcntl(*sock, F_SETFL, flags | O_NONBLOCK);
 183     }
 184 #endif /* O_NONBLOCK */
 185
 186    /*
 187     * Then connect...
 188     */
 189
 190     if (!connect(*sock, &(addrlist->addr.addr),
 191                  httpAddrLength(&(addrlist->addr))))
 192     {
 193       DEBUG_printf(("1httpAddrConnect2: Connected to %s:%d...",
 194                     httpAddrString(&(addrlist->addr), temp, sizeof(temp)),
 195                     httpAddrPort(&(addrlist->addr))));
 196
 197 #ifdef O_NONBLOCK
 198       fcntl(*sock, F_SETFL, flags);
 199 #endif /* O_NONBLOCK */
 200
 201       return (addrlist);
 202     }
 203
 204 #ifdef O_NONBLOCK
 205 #  ifdef WIN32
 206     if (WSAGetLastError() == WSAEINPROGRESS ||
 207         WSAGetLastError() == WSAEWOULDBLOCK)
 208 #  else
 209     if (errno == EINPROGRESS || errno == EWOULDBLOCK)
 210 #  endif /* WIN32 */
 211     {
 212       DEBUG_puts("1httpAddrConnect2: Finishing async connect()");
 213
 214       fcntl(*sock, F_SETFL, flags);
 215
 216       for (remaining = msec; remaining > 0; remaining -= 250)
 217       {
 218         do
 219         {
 220           if (cancel && *cancel)
 221           {
 222            /*
 223             * Close this socket and return...
 224             */
 225
 226             DEBUG_puts("1httpAddrConnect2: Canceled connect()");
 227
 228             httpAddrClose(NULL, *sock);
 229
 230             *sock = -1;
 231
 232             return (NULL);
 233           }
 234
 235 #  ifdef HAVE_POLL
 236           pfd.fd     = *sock;
 237           pfd.events = POLLIN | POLLOUT;
 238
 239           nfds = poll(&pfd, 1, remaining > 250 ? 250 : remaining);
 240
 241           DEBUG_printf(("1httpAddrConnect2: poll() returned %d (%d)", nfds,
 242                         errno));
 243
 244 #  else
 245           FD_ZERO(&input_set);
 246           FD_SET(*sock, &input_set);
 247           output_set = input_set;
 248
 249           timeout.tv_sec  = 0;
 250           timeout.tv_usec = (remaining > 250 ? 250 : remaining) * 1000;
 251
 252           nfds = select(*sock + 1, &input_set, &output_set, NULL, &timeout);
 253
 254           DEBUG_printf(("1httpAddrConnect2: select() returned %d (%d)", nfds,
 255                         errno));
 256 #  endif /* HAVE_POLL */
 257         }
 258 #  ifdef WIN32
 259         while (nfds < 0 && (WSAGetLastError() == WSAEINTR ||
 260                             WSAGetLastError() == WSAEWOULDBLOCK));
 261 #  else
 262         while (nfds < 0 && (errno == EINTR || errno == EAGAIN));
 263 #  endif /* WIN32 */
 264
 265         if (nfds > 0)
 266         {
 267           len = sizeof(peer);
 268           if (!getpeername(*sock, (struct sockaddr *)&peer, &len))
 269           {
 270             DEBUG_printf(("1httpAddrConnect2: Connected to %s:%d...",
 271                           httpAddrString(&peer, temp, sizeof(temp)),
 272                           httpAddrPort(&peer)));
 273
 274             return (addrlist);
 275           }
 276
 277           break;
 278         }
 279       }
 280     }
 281 #endif /* O_NONBLOCK */
 282
 283     DEBUG_printf(("1httpAddrConnect2: Unable to connect to %s:%d: %s",
 284                   httpAddrString(&(addrlist->addr), temp, sizeof(temp)),
 285                   httpAddrPort(&(addrlist->addr)), strerror(errno)));
 286
 287 #ifndef WIN32
 288     if (errno == EINPROGRESS)
 289       errno = ETIMEDOUT;
 290 #endif /* !WIN32 */
 291
 292    /*
 293     * Close this socket and move to the next address...
 294     */
 295
 296     httpAddrClose(NULL, *sock);
 297
 298     *sock    = -1;
 299     addrlist = addrlist->next;
 300   }
 301
 302   if (!addrlist)
 303 #ifdef WIN32
 304     _cupsSetError(IPP_STATUS_ERROR_SERVICE_UNAVAILABLE, "Connection failed", 0);
 305 #else
 306     _cupsSetError(IPP_STATUS_ERROR_SERVICE_UNAVAILABLE, strerror(errno), 0);
 307 #endif /* WIN32 */
 308
 309   return (addrlist);
 310 }
 311
 312
 313
 314 /*
 315  * 'httpAddrCopyList()' - Copy an address list.
 316  *
 317  * @since CUPS 1.7/OS X 10.9@
 318  */
 319
 320 http_addrlist_t *                       /* O - New address list or @code NULL@ on error */
 321 httpAddrCopyList(
 322     http_addrlist_t *src)               /* I - Source address list */
 323 {
 324   http_addrlist_t       *dst = NULL,    /* First list entry */
 325                         *prev = NULL,   /* Previous list entry */
 326                         *current = NULL;/* Current list entry */
 327
 328
 329   while (src)
 330   {
 331     if ((current = malloc(sizeof(http_addrlist_t))) == NULL)
 332     {
 333       current = dst;
 334
 335       while (current)
 336       {
 337         prev    = current;
 338         current = current->next;
 339
 340         free(prev);
 341       }
 342
 343       return (NULL);
 344     }
 345
 346     memcpy(current, src, sizeof(http_addrlist_t));
 347
 348     current->next = NULL;
 349
 350     if (prev)
 351       prev->next = current;
 352     else
 353       dst = current;
 354
 355     prev = current;
 356     src  = src->next;
 357   }
 358
 359   return (dst);
 360 }
 361
 362
 363 /*
 364  * 'httpAddrFreeList()' - Free an address list.
 365  *
 366  * @since CUPS 1.2/OS X 10.5@
 367  */
 368
 369 void
 370 httpAddrFreeList(
 371     http_addrlist_t *addrlist)          /* I - Address list to free */
 372 {
 373   http_addrlist_t       *next;          /* Next address in list */
 374
 375
 376  /*
 377   * Free each address in the list...
 378   */
 379
 380   while (addrlist)
 381   {
 382     next = addrlist->next;
 383
 384     free(addrlist);
 385
 386     addrlist = next;
 387   }
 388 }
 389
 390
 391 /*
 392  * 'httpAddrGetList()' - Get a list of addresses for a hostname.
 393  *
 394  * @since CUPS 1.2/OS X 10.5@
 395  */
 396
 397 http_addrlist_t *                       /* O - List of addresses or NULL */
 398 httpAddrGetList(const char *hostname,   /* I - Hostname, IP address, or NULL for passive listen address */
 399                 int        family,      /* I - Address family or AF_UNSPEC */
 400                 const char *service)    /* I - Service name or port number */
 401 {
 402   http_addrlist_t       *first,         /* First address in list */
 403                         *addr,          /* Current address in list */
 404                         *temp;          /* New address */
 405   _cups_globals_t       *cg = _cupsGlobals();
 406                                         /* Global data */
 407
 408
 409 #ifdef DEBUG
 410   _cups_debug_printf("httpAddrGetList(hostname=\"%s\", family=AF_%s, "
 411                      "service=\"%s\")\n",
 412                      hostname ? hostname : "(nil)",
 413                      family == AF_UNSPEC ? "UNSPEC" :
 414 #  ifdef AF_LOCAL
 415                          family == AF_LOCAL ? "LOCAL" :
 416 #  endif /* AF_LOCAL */
 417 #  ifdef AF_INET6
 418                          family == AF_INET6 ? "INET6" :
 419 #  endif /* AF_INET6 */
 420                          family == AF_INET ? "INET" : "???", service);
 421 #endif /* DEBUG */
 422
 423 #ifdef HAVE_RES_INIT
 424  /*
 425   * STR #2920: Initialize resolver after failure in cups-polld
 426   *
 427   * If the previous lookup failed, re-initialize the resolver to prevent
 428   * temporary network errors from persisting.  This *should* be handled by
 429   * the resolver libraries, but apparently the glibc folks do not agree.
 430   *
 431   * We set a flag at the end of this function if we encounter an error that
 432   * requires reinitialization of the resolver functions.  We then call
 433   * res_init() if the flag is set on the next call here or in httpAddrLookup().
 434   */
 435
 436   if (cg->need_res_init)
 437   {
 438     res_init();
 439
 440     cg->need_res_init = 0;
 441   }
 442 #endif /* HAVE_RES_INIT */
 443
 444  /*
 445   * Lookup the address the best way we can...
 446   */
 447
 448   first = addr = NULL;
 449
 450 #ifdef AF_LOCAL
 451   if (hostname && hostname[0] == '/')
 452   {
 453    /*
 454     * Domain socket address...
 455     */
 456
 457     if ((first = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t))) != NULL)
 458     {
 459       first->addr.un.sun_family = AF_LOCAL;
 460       strlcpy(first->addr.un.sun_path, hostname, sizeof(first->addr.un.sun_path));
 461     }
 462   }
 463   else
 464 #endif /* AF_LOCAL */
 465   if (!hostname || _cups_strcasecmp(hostname, "localhost"))
 466   {
 467 #ifdef HAVE_GETADDRINFO
 468     struct addrinfo     hints,          /* Address lookup hints */
 469                         *results,       /* Address lookup results */
 470                         *current;       /* Current result */
 471     char                ipv6[64],       /* IPv6 address */
 472                         *ipv6zone;      /* Pointer to zone separator */
 473     int                 ipv6len;        /* Length of IPv6 address */
 474     int                 error;          /* getaddrinfo() error */
 475
 476
 477    /*
 478     * Lookup the address as needed...
 479     */
 480
 481     memset(&hints, 0, sizeof(hints));
 482     hints.ai_family   = family;
 483     hints.ai_flags    = hostname ? 0 : AI_PASSIVE;
 484     hints.ai_socktype = SOCK_STREAM;
 485
 486     if (hostname && *hostname == '[')
 487     {
 488      /*
 489       * Remove brackets from numeric IPv6 address...
 490       */
 491
 492       if (!strncmp(hostname, "[v1.", 4))
 493       {
 494        /*
 495         * Copy the newer address format which supports link-local addresses...
 496         */
 497
 498         strlcpy(ipv6, hostname + 4, sizeof(ipv6));
 499         if ((ipv6len = (int)strlen(ipv6) - 1) >= 0 && ipv6[ipv6len] == ']')
 500         {
 501           ipv6[ipv6len] = '\0';
 502           hostname      = ipv6;
 503
 504          /*
 505           * Convert "+zone" in address to "%zone"...
 506           */
 507
 508           if ((ipv6zone = strrchr(ipv6, '+')) != NULL)
 509             *ipv6zone = '%';
 510         }
 511       }
 512       else
 513       {
 514        /*
 515         * Copy the regular non-link-local IPv6 address...
 516         */
 517
 518         strlcpy(ipv6, hostname + 1, sizeof(ipv6));
 519         if ((ipv6len = (int)strlen(ipv6) - 1) >= 0 && ipv6[ipv6len] == ']')
 520         {
 521           ipv6[ipv6len] = '\0';
 522           hostname      = ipv6;
 523         }
 524       }
 525     }
 526
 527     if ((error = getaddrinfo(hostname, service, &hints, &results)) == 0)
 528     {
 529      /*
 530       * Copy the results to our own address list structure...
 531       */
 532
 533       for (current = results; current; current = current->ai_next)
 534         if (current->ai_family == AF_INET || current->ai_family == AF_INET6)
 535         {
 536          /*
 537           * Copy the address over...
 538           */
 539
 540           temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 541           if (!temp)
 542           {
 543             httpAddrFreeList(first);
 544             _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
 545             return (NULL);
 546           }
 547
 548           if (current->ai_family == AF_INET6)
 549             memcpy(&(temp->addr.ipv6), current->ai_addr,
 550                    sizeof(temp->addr.ipv6));
 551           else
 552             memcpy(&(temp->addr.ipv4), current->ai_addr,
 553                    sizeof(temp->addr.ipv4));
 554
 555          /*
 556           * Append the address to the list...
 557           */
 558
 559           if (!first)
 560             first = temp;
 561
 562           if (addr)
 563             addr->next = temp;
 564
 565           addr = temp;
 566         }
 567
 568      /*
 569       * Free the results from getaddrinfo()...
 570       */
 571
 572       freeaddrinfo(results);
 573     }
 574     else
 575     {
 576       if (error == EAI_FAIL)
 577         cg->need_res_init = 1;
 578
 579       _cupsSetError(IPP_STATUS_ERROR_INTERNAL, gai_strerror(error), 0);
 580     }
 581
 582 #else
 583     if (hostname)
 584     {
 585       int               i;              /* Looping vars */
 586       unsigned          ip[4];          /* IPv4 address components */
 587       const char        *ptr;           /* Pointer into hostname */
 588       struct hostent    *host;          /* Result of lookup */
 589       struct servent    *port;          /* Port number for service */
 590       int               portnum;        /* Port number */
 591
 592
 593      /*
 594       * Lookup the service...
 595       */
 596
 597       if (!service)
 598         portnum = 0;
 599       else if (isdigit(*service & 255))
 600         portnum = atoi(service);
 601       else if ((port = getservbyname(service, NULL)) != NULL)
 602         portnum = ntohs(port->s_port);
 603       else if (!strcmp(service, "http"))
 604         portnum = 80;
 605       else if (!strcmp(service, "https"))
 606         portnum = 443;
 607       else if (!strcmp(service, "ipp") || !strcmp(service, "ipps"))
 608         portnum = 631;
 609       else if (!strcmp(service, "lpd"))
 610         portnum = 515;
 611       else if (!strcmp(service, "socket"))
 612         portnum = 9100;
 613       else
 614         return (NULL);
 615
 616      /*
 617       * This code is needed because some operating systems have a
 618       * buggy implementation of gethostbyname() that does not support
 619       * IPv4 addresses.  If the hostname string is an IPv4 address, then
 620       * sscanf() is used to extract the IPv4 components.  We then pack
 621       * the components into an IPv4 address manually, since the
 622       * inet_aton() function is deprecated.  We use the htonl() macro
 623       * to get the right byte order for the address.
 624       */
 625
 626       for (ptr = hostname; isdigit(*ptr & 255) || *ptr == '.'; ptr ++);
 627
 628       if (!*ptr)
 629       {
 630        /*
 631         * We have an IPv4 address; break it up and create an IPv4 address...
 632         */
 633
 634         if (sscanf(hostname, "%u.%u.%u.%u", ip, ip + 1, ip + 2, ip + 3) == 4 &&
 635             ip[0] <= 255 && ip[1] <= 255 && ip[2] <= 255 && ip[3] <= 255)
 636         {
 637           first = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 638           if (!first)
 639             return (NULL);
 640
 641           first->addr.ipv4.sin_family = AF_INET;
 642           first->addr.ipv4.sin_addr.s_addr = htonl(((((((ip[0] << 8) |
 643                                                        ip[1]) << 8) |
 644                                                      ip[2]) << 8) | ip[3]));
 645           first->addr.ipv4.sin_port = htons(portnum);
 646         }
 647       }
 648       else if ((host = gethostbyname(hostname)) != NULL &&
 649 #  ifdef AF_INET6
 650                (host->h_addrtype == AF_INET || host->h_addrtype == AF_INET6))
 651 #  else
 652                host->h_addrtype == AF_INET)
 653 #  endif /* AF_INET6 */
 654       {
 655         for (i = 0; host->h_addr_list[i]; i ++)
 656         {
 657          /*
 658           * Copy the address over...
 659           */
 660
 661           temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 662           if (!temp)
 663           {
 664             httpAddrFreeList(first);
 665             return (NULL);
 666           }
 667
 668 #  ifdef AF_INET6
 669           if (host->h_addrtype == AF_INET6)
 670           {
 671             temp->addr.ipv6.sin6_family = AF_INET6;
 672             memcpy(&(temp->addr.ipv6.sin6_addr), host->h_addr_list[i],
 673                    sizeof(temp->addr.ipv6));
 674             temp->addr.ipv6.sin6_port = htons(portnum);
 675           }
 676           else
 677 #  endif /* AF_INET6 */
 678           {
 679             temp->addr.ipv4.sin_family = AF_INET;
 680             memcpy(&(temp->addr.ipv4.sin_addr), host->h_addr_list[i],
 681                    sizeof(temp->addr.ipv4));
 682             temp->addr.ipv4.sin_port = htons(portnum);
 683           }
 684
 685          /*
 686           * Append the address to the list...
 687           */
 688
 689           if (!first)
 690             first = temp;
 691
 692           if (addr)
 693             addr->next = temp;
 694
 695           addr = temp;
 696         }
 697       }
 698       else
 699       {
 700         if (h_errno == NO_RECOVERY)
 701           cg->need_res_init = 1;
 702
 703         _cupsSetError(IPP_STATUS_ERROR_INTERNAL, hstrerror(h_errno), 0);
 704       }
 705     }
 706 #endif /* HAVE_GETADDRINFO */
 707   }
 708
 709  /*
 710   * Detect some common errors and handle them sanely...
 711   */
 712
 713   if (!addr && (!hostname || !_cups_strcasecmp(hostname, "localhost")))
 714   {
 715     struct servent      *port;          /* Port number for service */
 716     int                 portnum;        /* Port number */
 717
 718
 719    /*
 720     * Lookup the service...
 721     */
 722
 723     if (!service)
 724       portnum = 0;
 725     else if (isdigit(*service & 255))
 726       portnum = atoi(service);
 727     else if ((port = getservbyname(service, NULL)) != NULL)
 728       portnum = ntohs(port->s_port);
 729     else if (!strcmp(service, "http"))
 730       portnum = 80;
 731     else if (!strcmp(service, "https"))
 732       portnum = 443;
 733     else if (!strcmp(service, "ipp") || !strcmp(service, "ipps"))
 734       portnum = 631;
 735     else if (!strcmp(service, "lpd"))
 736       portnum = 515;
 737     else if (!strcmp(service, "socket"))
 738       portnum = 9100;
 739     else
 740     {
 741       httpAddrFreeList(first);
 742
 743       _cupsSetError(IPP_STATUS_ERROR_INTERNAL, _("Unknown service name."), 1);
 744       return (NULL);
 745     }
 746
 747     if (hostname && !_cups_strcasecmp(hostname, "localhost"))
 748     {
 749      /*
 750       * Unfortunately, some users ignore all of the warnings in the
 751       * /etc/hosts file and delete "localhost" from it. If we get here
 752       * then we were unable to resolve the name, so use the IPv6 and/or
 753       * IPv4 loopback interface addresses...
 754       */
 755
 756 #ifdef AF_INET6
 757       if (family != AF_INET)
 758       {
 759        /*
 760         * Add [::1] to the address list...
 761         */
 762
 763         temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 764         if (!temp)
 765         {
 766           _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
 767           httpAddrFreeList(first);
 768           return (NULL);
 769         }
 770
 771         temp->addr.ipv6.sin6_family            = AF_INET6;
 772         temp->addr.ipv6.sin6_port              = htons(portnum);
 773 #  ifdef WIN32
 774         temp->addr.ipv6.sin6_addr.u.Byte[15]   = 1;
 775 #  else
 776         temp->addr.ipv6.sin6_addr.s6_addr32[3] = htonl(1);
 777 #  endif /* WIN32 */
 778
 779         if (!first)
 780           first = temp;
 781
 782         addr = temp;
 783       }
 784
 785       if (family != AF_INET6)
 786 #endif /* AF_INET6 */
 787       {
 788        /*
 789         * Add 127.0.0.1 to the address list...
 790         */
 791
 792         temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 793         if (!temp)
 794         {
 795           _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
 796           httpAddrFreeList(first);
 797           return (NULL);
 798         }
 799
 800         temp->addr.ipv4.sin_family      = AF_INET;
 801         temp->addr.ipv4.sin_port        = htons(portnum);
 802         temp->addr.ipv4.sin_addr.s_addr = htonl(0x7f000001);
 803
 804         if (!first)
 805           first = temp;
 806
 807         if (addr)
 808           addr->next = temp;
 809       }
 810     }
 811     else if (!hostname)
 812     {
 813      /*
 814       * Provide one or more passive listening addresses...
 815       */
 816
 817 #ifdef AF_INET6
 818       if (family != AF_INET)
 819       {
 820        /*
 821         * Add [::] to the address list...
 822         */
 823
 824         temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 825         if (!temp)
 826         {
 827           _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
 828           httpAddrFreeList(first);
 829           return (NULL);
 830         }
 831
 832         temp->addr.ipv6.sin6_family = AF_INET6;
 833         temp->addr.ipv6.sin6_port   = htons(portnum);
 834
 835         if (!first)
 836           first = temp;
 837
 838         addr = temp;
 839       }
 840
 841       if (family != AF_INET6)
 842 #endif /* AF_INET6 */
 843       {
 844        /*
 845         * Add 0.0.0.0 to the address list...
 846         */
 847
 848         temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 849         if (!temp)
 850         {
 851           _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
 852           httpAddrFreeList(first);
 853           return (NULL);
 854         }
 855
 856         temp->addr.ipv4.sin_family = AF_INET;
 857         temp->addr.ipv4.sin_port   = htons(portnum);
 858
 859         if (!first)
 860           first = temp;
 861
 862         if (addr)
 863           addr->next = temp;
 864       }
 865     }
 866   }
 867
 868  /*
 869   * Return the address list...
 870   */
 871
 872   return (first);
 873 }
 874
 875
 876 /*
 877  * End of "$Id$".
 878  */