cups/http-addrlist.c

   1 /*
   2  * "$Id: http-addrlist.c 7910 2008-09-06 00:25:17Z mike $"
   3  *
   4  *   HTTP address list routines for CUPS.
   5  *
   6  *   Copyright 2007-2012 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  *   httpAddrFreeList() - Free an address list.
  21  *   httpAddrGetList()  - Get a list of addresses for a hostname.
  22  */
  23
  24 /*
  25  * Include necessary headers...
  26  */
  27
  28 #include "cups-private.h"
  29 #ifdef HAVE_RESOLV_H
  30 #  include <resolv.h>
  31 #endif /* HAVE_RESOLV_H */
  32 #ifdef HAVE_POLL
  33 #  include <poll.h>
  34 #endif /* HAVE_POLL */
  35 #ifndef WIN32
  36 #  include <sys/fcntl.h>
  37 #endif /* WIN32 */
  38
  39
  40 /*
  41  * 'httpAddrConnect()' - Connect to any of the addresses in the list.
  42  *
  43  * @since CUPS 1.2/Mac OS X 10.5@
  44  */
  45
  46 http_addrlist_t *                       /* O - Connected address or NULL on failure */
  47 httpAddrConnect(
  48     http_addrlist_t *addrlist,          /* I - List of potential addresses */
  49     int             *sock)              /* O - Socket */
  50 {
  51   DEBUG_printf(("httpAddrConnect(addrlist=%p, sock=%p)", addrlist, sock));
  52
  53   return (httpAddrConnect2(addrlist, sock, 30000, NULL));
  54 }
  55
  56
  57 /*
  58  * 'httpAddrConnect2()' - Connect to any of the addresses in the list with a
  59  *                        timeout and optional cancel.
  60  *
  61  * @since CUPS 1.6@
  62  */
  63
  64 http_addrlist_t *                       /* O - Connected address or NULL on failure */
  65 httpAddrConnect2(
  66     http_addrlist_t *addrlist,          /* I - List of potential addresses */
  67     int             *sock,              /* O - Socket */
  68     int             msec,               /* I - Timeout in milliseconds */
  69     int             *cancel)            /* I - Pointer to "cancel" variable */
  70 {
  71   int                   val;            /* Socket option value */
  72 #ifdef O_NONBLOCK
  73   socklen_t             len;            /* Length of value */
  74   http_addr_t           peer;           /* Peer address */
  75   int                   flags,          /* Socket flags */
  76                         remaining;      /* Remaining timeout */
  77 #  ifdef HAVE_POLL
  78   struct pollfd         pfd;            /* Polled file descriptor */
  79 #  else
  80   fd_set                input_set,      /* select() input set */
  81                         output_set;     /* select() output set */
  82   struct timeval        timeout;        /* Timeout */
  83 #  endif /* HAVE_POLL */
  84   int                   nfds;           /* Result from select()/poll() */
  85 #endif /* O_NONBLOCK */
  86 #ifdef DEBUG
  87   char                  temp[256];      /* Temporary address string */
  88 #endif /* DEBUG */
  89
  90
  91   DEBUG_printf(("httpAddrConnect2(addrlist=%p, sock=%p, msec=%d, cancel=%p)",
  92                 addrlist, sock, msec, cancel));
  93
  94   if (!sock)
  95   {
  96     errno = EINVAL;
  97     _cupsSetError(IPP_INTERNAL_ERROR, strerror(errno), 0);
  98     return (NULL);
  99   }
 100
 101   if (cancel && *cancel)
 102     return (NULL);
 103
 104   if (msec <= 0 || getenv("CUPS_DISABLE_ASYNC_CONNECT"))
 105     msec = INT_MAX;
 106
 107  /*
 108   * Loop through each address until we connect or run out of addresses...
 109   */
 110
 111   while (addrlist)
 112   {
 113     if (cancel && *cancel)
 114       return (NULL);
 115
 116    /*
 117     * Create the socket...
 118     */
 119
 120     DEBUG_printf(("2httpAddrConnect2: Trying %s:%d...",
 121                   httpAddrString(&(addrlist->addr), temp, sizeof(temp)),
 122                   _httpAddrPort(&(addrlist->addr))));
 123
 124     if ((*sock = (int)socket(_httpAddrFamily(&(addrlist->addr)), SOCK_STREAM,
 125                              0)) < 0)
 126     {
 127      /*
 128       * Don't abort yet, as this could just be an issue with the local
 129       * system not being configured with IPv4/IPv6/domain socket enabled...
 130       */
 131
 132       addrlist = addrlist->next;
 133       continue;
 134     }
 135
 136    /*
 137     * Set options...
 138     */
 139
 140     val = 1;
 141 #ifdef WIN32
 142     setsockopt(*sock, SOL_SOCKET, SO_REUSEADDR, (const char *)&val,
 143                sizeof(val));
 144 #else
 145     setsockopt(*sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
 146 #endif /* WIN32 */
 147
 148 #ifdef SO_REUSEPORT
 149     val = 1;
 150     setsockopt(*sock, SOL_SOCKET, SO_REUSEPORT, &val, sizeof(val));
 151 #endif /* SO_REUSEPORT */
 152
 153 #ifdef SO_NOSIGPIPE
 154     val = 1;
 155     setsockopt(*sock, SOL_SOCKET, SO_NOSIGPIPE, &val, sizeof(val));
 156 #endif /* SO_NOSIGPIPE */
 157
 158    /*
 159     * Using TCP_NODELAY improves responsiveness, especially on systems
 160     * with a slow loopback interface...
 161     */
 162
 163     val = 1;
 164 #ifdef WIN32
 165     setsockopt(*sock, IPPROTO_TCP, TCP_NODELAY, (const char *)&val,
 166                sizeof(val));
 167 #else
 168     setsockopt(*sock, IPPROTO_TCP, TCP_NODELAY, &val, sizeof(val));
 169 #endif /* WIN32 */
 170
 171 #ifdef FD_CLOEXEC
 172    /*
 173     * Close this socket when starting another process...
 174     */
 175
 176     fcntl(*sock, F_SETFD, FD_CLOEXEC);
 177 #endif /* FD_CLOEXEC */
 178
 179 #ifdef O_NONBLOCK
 180    /*
 181     * Do an asynchronous connect by setting the socket non-blocking...
 182     */
 183
 184     DEBUG_printf(("httpAddrConnect2: Setting non-blocking connect()"));
 185
 186     flags = fcntl(*sock, F_GETFL, 0);
 187     if (msec != INT_MAX)
 188     {
 189       DEBUG_puts("httpAddrConnect2: Setting non-blocking connect()");
 190
 191       fcntl(*sock, F_SETFL, flags | O_NONBLOCK);
 192     }
 193 #endif /* O_NONBLOCK */
 194
 195    /*
 196     * Then connect...
 197     */
 198
 199     if (!connect(*sock, &(addrlist->addr.addr),
 200                  httpAddrLength(&(addrlist->addr))))
 201     {
 202       DEBUG_printf(("1httpAddrConnect2: Connected to %s:%d...",
 203                     httpAddrString(&(addrlist->addr), temp, sizeof(temp)),
 204                     _httpAddrPort(&(addrlist->addr))));
 205
 206 #ifdef O_NONBLOCK
 207       fcntl(*sock, F_SETFL, flags);
 208 #endif /* O_NONBLOCK */
 209
 210       return (addrlist);
 211     }
 212
 213 #ifdef O_NONBLOCK
 214 #  ifdef WIN32
 215     if (WSAGetLastError() == WSAEINPROGRESS ||
 216         WSAGetLastError() == WSAEWOULDBLOCK)
 217 #  else
 218     if (errno == EINPROGRESS || errno == EWOULDBLOCK)
 219 #  endif /* WIN32 */
 220     {
 221       DEBUG_puts("1httpAddrConnect2: Finishing async connect()");
 222
 223       fcntl(*sock, F_SETFL, flags);
 224
 225       for (remaining = msec; remaining > 0; remaining -= 250)
 226       {
 227         do
 228         {
 229           if (cancel && *cancel)
 230           {
 231            /*
 232             * Close this socket and return...
 233             */
 234
 235             DEBUG_puts("1httpAddrConnect2: Canceled connect()");
 236
 237 #    ifdef WIN32
 238             closesocket(*sock);
 239 #    else
 240             close(*sock);
 241 #    endif /* WIN32 */
 242
 243             *sock = -1;
 244
 245             return (NULL);
 246           }
 247
 248 #  ifdef HAVE_POLL
 249           pfd.fd     = *sock;
 250           pfd.events = POLLIN | POLLOUT;
 251
 252           nfds = poll(&pfd, 1, remaining > 250 ? 250 : remaining);
 253
 254           DEBUG_printf(("1httpAddrConnect2: poll() returned %d (%d)", nfds,
 255                         errno));
 256
 257 #  else
 258           FD_ZERO(&input_set);
 259           FD_SET(*sock, &input_set);
 260           output_set = input_set;
 261
 262           timeout.tv_sec  = 0;
 263           timeout.tv_usec = (remaining > 250 ? 250 : remaining) * 1000;
 264
 265           nfds = select(*sock + 1, &input_set, &output_set, NULL, &timeout);
 266
 267           DEBUG_printf(("1httpAddrConnect2: select() returned %d (%d)", nfds,
 268                         errno));
 269 #  endif /* HAVE_POLL */
 270         }
 271 #  ifdef WIN32
 272         while (nfds < 0 && (WSAGetLastError() == WSAEINTR ||
 273                             WSAGetLastError() == WSAEWOULDBLOCK));
 274 #  else
 275         while (nfds < 0 && (errno == EINTR || errno == EAGAIN));
 276 #  endif /* WIN32 */
 277
 278         if (nfds > 0)
 279         {
 280           len = sizeof(peer);
 281           if (!getpeername(*sock, (struct sockaddr *)&peer, &len))
 282           {
 283             DEBUG_printf(("1httpAddrConnect2: Connected to %s:%d...",
 284                           httpAddrString(&peer, temp, sizeof(temp)),
 285                           _httpAddrPort(&peer)));
 286
 287             return (addrlist);
 288           }
 289
 290           break;
 291         }
 292       }
 293     }
 294 #endif /* O_NONBLOCK */
 295
 296     DEBUG_printf(("1httpAddrConnect2: Unable to connect to %s:%d: %s",
 297                   httpAddrString(&(addrlist->addr), temp, sizeof(temp)),
 298                   _httpAddrPort(&(addrlist->addr)), strerror(errno)));
 299
 300 #ifndef WIN32
 301     if (errno == EINPROGRESS)
 302       errno = ETIMEDOUT;
 303 #endif /* !WIN32 */
 304
 305    /*
 306     * Close this socket and move to the next address...
 307     */
 308
 309 #ifdef WIN32
 310     closesocket(*sock);
 311 #else
 312     close(*sock);
 313 #endif /* WIN32 */
 314
 315     *sock    = -1;
 316     addrlist = addrlist->next;
 317   }
 318
 319   if (!addrlist)
 320 #ifdef WIN32
 321     _cupsSetError(IPP_SERVICE_UNAVAILABLE, "Connection failed", 0);
 322 #else
 323     _cupsSetError(IPP_SERVICE_UNAVAILABLE, strerror(errno), 0);
 324 #endif /* WIN32 */
 325
 326   return (addrlist);
 327 }
 328
 329
 330 /*
 331  * 'httpAddrFreeList()' - Free an address list.
 332  *
 333  * @since CUPS 1.2/Mac OS X 10.5@
 334  */
 335
 336 void
 337 httpAddrFreeList(
 338     http_addrlist_t *addrlist)          /* I - Address list to free */
 339 {
 340   http_addrlist_t       *next;          /* Next address in list */
 341
 342
 343  /*
 344   * Free each address in the list...
 345   */
 346
 347   while (addrlist)
 348   {
 349     next = addrlist->next;
 350
 351     free(addrlist);
 352
 353     addrlist = next;
 354   }
 355 }
 356
 357
 358 /*
 359  * 'httpAddrGetList()' - Get a list of addresses for a hostname.
 360  *
 361  * @since CUPS 1.2/Mac OS X 10.5@
 362  */
 363
 364 http_addrlist_t *                       /* O - List of addresses or NULL */
 365 httpAddrGetList(const char *hostname,   /* I - Hostname, IP address, or NULL for passive listen address */
 366                 int        family,      /* I - Address family or AF_UNSPEC */
 367                 const char *service)    /* I - Service name or port number */
 368 {
 369   http_addrlist_t       *first,         /* First address in list */
 370                         *addr,          /* Current address in list */
 371                         *temp;          /* New address */
 372   _cups_globals_t       *cg = _cupsGlobals();
 373                                         /* Global data */
 374
 375
 376 #ifdef DEBUG
 377   _cups_debug_printf("httpAddrGetList(hostname=\"%s\", family=AF_%s, "
 378                      "service=\"%s\")\n",
 379                      hostname ? hostname : "(nil)",
 380                      family == AF_UNSPEC ? "UNSPEC" :
 381 #  ifdef AF_LOCAL
 382                          family == AF_LOCAL ? "LOCAL" :
 383 #  endif /* AF_LOCAL */
 384 #  ifdef AF_INET6
 385                          family == AF_INET6 ? "INET6" :
 386 #  endif /* AF_INET6 */
 387                          family == AF_INET ? "INET" : "???", service);
 388 #endif /* DEBUG */
 389
 390 #ifdef HAVE_RES_INIT
 391  /*
 392   * STR #2920: Initialize resolver after failure in cups-polld
 393   *
 394   * If the previous lookup failed, re-initialize the resolver to prevent
 395   * temporary network errors from persisting.  This *should* be handled by
 396   * the resolver libraries, but apparently the glibc folks do not agree.
 397   *
 398   * We set a flag at the end of this function if we encounter an error that
 399   * requires reinitialization of the resolver functions.  We then call
 400   * res_init() if the flag is set on the next call here or in httpAddrLookup().
 401   */
 402
 403   if (cg->need_res_init)
 404   {
 405     res_init();
 406
 407     cg->need_res_init = 0;
 408   }
 409 #endif /* HAVE_RES_INIT */
 410
 411  /*
 412   * Lookup the address the best way we can...
 413   */
 414
 415   first = addr = NULL;
 416
 417 #ifdef AF_LOCAL
 418   if (hostname && hostname[0] == '/')
 419   {
 420    /*
 421     * Domain socket address...
 422     */
 423
 424     if ((first = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t))) != NULL)
 425     {
 426       first->addr.un.sun_family = AF_LOCAL;
 427       strlcpy(first->addr.un.sun_path, hostname, sizeof(first->addr.un.sun_path));
 428     }
 429   }
 430   else
 431 #endif /* AF_LOCAL */
 432   if (!hostname || _cups_strcasecmp(hostname, "localhost"))
 433   {
 434 #ifdef HAVE_GETADDRINFO
 435     struct addrinfo     hints,          /* Address lookup hints */
 436                         *results,       /* Address lookup results */
 437                         *current;       /* Current result */
 438     char                ipv6[64],       /* IPv6 address */
 439                         *ipv6zone;      /* Pointer to zone separator */
 440     int                 ipv6len;        /* Length of IPv6 address */
 441     int                 error;          /* getaddrinfo() error */
 442
 443
 444    /*
 445     * Lookup the address as needed...
 446     */
 447
 448     memset(&hints, 0, sizeof(hints));
 449     hints.ai_family   = family;
 450     hints.ai_flags    = hostname ? 0 : AI_PASSIVE;
 451     hints.ai_socktype = SOCK_STREAM;
 452
 453     if (hostname && *hostname == '[')
 454     {
 455      /*
 456       * Remove brackets from numeric IPv6 address...
 457       */
 458
 459       if (!strncmp(hostname, "[v1.", 4))
 460       {
 461        /*
 462         * Copy the newer address format which supports link-local addresses...
 463         */
 464
 465         strlcpy(ipv6, hostname + 4, sizeof(ipv6));
 466         if ((ipv6len = (int)strlen(ipv6) - 1) >= 0 && ipv6[ipv6len] == ']')
 467         {
 468           ipv6[ipv6len] = '\0';
 469           hostname      = ipv6;
 470
 471          /*
 472           * Convert "+zone" in address to "%zone"...
 473           */
 474
 475           if ((ipv6zone = strrchr(ipv6, '+')) != NULL)
 476             *ipv6zone = '%';
 477         }
 478       }
 479       else
 480       {
 481        /*
 482         * Copy the regular non-link-local IPv6 address...
 483         */
 484
 485         strlcpy(ipv6, hostname + 1, sizeof(ipv6));
 486         if ((ipv6len = (int)strlen(ipv6) - 1) >= 0 && ipv6[ipv6len] == ']')
 487         {
 488           ipv6[ipv6len] = '\0';
 489           hostname      = ipv6;
 490         }
 491       }
 492     }
 493
 494     if ((error = getaddrinfo(hostname, service, &hints, &results)) == 0)
 495     {
 496      /*
 497       * Copy the results to our own address list structure...
 498       */
 499
 500       for (current = results; current; current = current->ai_next)
 501         if (current->ai_family == AF_INET || current->ai_family == AF_INET6)
 502         {
 503          /*
 504           * Copy the address over...
 505           */
 506
 507           temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 508           if (!temp)
 509           {
 510             httpAddrFreeList(first);
 511             _cupsSetError(IPP_INTERNAL_ERROR, strerror(errno), 0);
 512             return (NULL);
 513           }
 514
 515           if (current->ai_family == AF_INET6)
 516             memcpy(&(temp->addr.ipv6), current->ai_addr,
 517                    sizeof(temp->addr.ipv6));
 518           else
 519             memcpy(&(temp->addr.ipv4), current->ai_addr,
 520                    sizeof(temp->addr.ipv4));
 521
 522          /*
 523           * Append the address to the list...
 524           */
 525
 526           if (!first)
 527             first = temp;
 528
 529           if (addr)
 530             addr->next = temp;
 531
 532           addr = temp;
 533         }
 534
 535      /*
 536       * Free the results from getaddrinfo()...
 537       */
 538
 539       freeaddrinfo(results);
 540     }
 541     else
 542     {
 543       if (error == EAI_FAIL)
 544         cg->need_res_init = 1;
 545
 546       _cupsSetError(IPP_INTERNAL_ERROR, gai_strerror(error), 0);
 547     }
 548
 549 #else
 550     if (hostname)
 551     {
 552       int               i;              /* Looping vars */
 553       unsigned          ip[4];          /* IPv4 address components */
 554       const char        *ptr;           /* Pointer into hostname */
 555       struct hostent    *host;          /* Result of lookup */
 556       struct servent    *port;          /* Port number for service */
 557       int               portnum;        /* Port number */
 558
 559
 560      /*
 561       * Lookup the service...
 562       */
 563
 564       if (!service)
 565         portnum = 0;
 566       else if (isdigit(*service & 255))
 567         portnum = atoi(service);
 568       else if ((port = getservbyname(service, NULL)) != NULL)
 569         portnum = ntohs(port->s_port);
 570       else if (!strcmp(service, "http"))
 571         portnum = 80;
 572       else if (!strcmp(service, "https"))
 573         portnum = 443;
 574       else if (!strcmp(service, "ipp") || !strcmp(service, "ipps"))
 575         portnum = 631;
 576       else if (!strcmp(service, "lpd"))
 577         portnum = 515;
 578       else if (!strcmp(service, "socket"))
 579         portnum = 9100;
 580       else
 581         return (NULL);
 582
 583      /*
 584       * This code is needed because some operating systems have a
 585       * buggy implementation of gethostbyname() that does not support
 586       * IPv4 addresses.  If the hostname string is an IPv4 address, then
 587       * sscanf() is used to extract the IPv4 components.  We then pack
 588       * the components into an IPv4 address manually, since the
 589       * inet_aton() function is deprecated.  We use the htonl() macro
 590       * to get the right byte order for the address.
 591       */
 592
 593       for (ptr = hostname; isdigit(*ptr & 255) || *ptr == '.'; ptr ++);
 594
 595       if (!*ptr)
 596       {
 597        /*
 598         * We have an IPv4 address; break it up and create an IPv4 address...
 599         */
 600
 601         if (sscanf(hostname, "%u.%u.%u.%u", ip, ip + 1, ip + 2, ip + 3) == 4 &&
 602             ip[0] <= 255 && ip[1] <= 255 && ip[2] <= 255 && ip[3] <= 255)
 603         {
 604           first = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 605           if (!first)
 606             return (NULL);
 607
 608           first->addr.ipv4.sin_family = AF_INET;
 609           first->addr.ipv4.sin_addr.s_addr = htonl(((((((ip[0] << 8) |
 610                                                        ip[1]) << 8) |
 611                                                      ip[2]) << 8) | ip[3]));
 612           first->addr.ipv4.sin_port = htons(portnum);
 613         }
 614       }
 615       else if ((host = gethostbyname(hostname)) != NULL &&
 616 #  ifdef AF_INET6
 617                (host->h_addrtype == AF_INET || host->h_addrtype == AF_INET6))
 618 #  else
 619                host->h_addrtype == AF_INET)
 620 #  endif /* AF_INET6 */
 621       {
 622         for (i = 0; host->h_addr_list[i]; i ++)
 623         {
 624          /*
 625           * Copy the address over...
 626           */
 627
 628           temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 629           if (!temp)
 630           {
 631             httpAddrFreeList(first);
 632             return (NULL);
 633           }
 634
 635 #  ifdef AF_INET6
 636           if (host->h_addrtype == AF_INET6)
 637           {
 638             temp->addr.ipv6.sin6_family = AF_INET6;
 639             memcpy(&(temp->addr.ipv6.sin6_addr), host->h_addr_list[i],
 640                    sizeof(temp->addr.ipv6));
 641             temp->addr.ipv6.sin6_port = htons(portnum);
 642           }
 643           else
 644 #  endif /* AF_INET6 */
 645           {
 646             temp->addr.ipv4.sin_family = AF_INET;
 647             memcpy(&(temp->addr.ipv4.sin_addr), host->h_addr_list[i],
 648                    sizeof(temp->addr.ipv4));
 649             temp->addr.ipv4.sin_port = htons(portnum);
 650           }
 651
 652          /*
 653           * Append the address to the list...
 654           */
 655
 656           if (!first)
 657             first = temp;
 658
 659           if (addr)
 660             addr->next = temp;
 661
 662           addr = temp;
 663         }
 664       }
 665       else
 666       {
 667         if (h_errno == NO_RECOVERY)
 668           cg->need_res_init = 1;
 669
 670         _cupsSetError(IPP_INTERNAL_ERROR, hstrerror(h_errno), 0);
 671       }
 672     }
 673 #endif /* HAVE_GETADDRINFO */
 674   }
 675
 676  /*
 677   * Detect some common errors and handle them sanely...
 678   */
 679
 680   if (!addr && (!hostname || !_cups_strcasecmp(hostname, "localhost")))
 681   {
 682     struct servent      *port;          /* Port number for service */
 683     int                 portnum;        /* Port number */
 684
 685
 686    /*
 687     * Lookup the service...
 688     */
 689
 690     if (!service)
 691       portnum = 0;
 692     else if (isdigit(*service & 255))
 693       portnum = atoi(service);
 694     else if ((port = getservbyname(service, NULL)) != NULL)
 695       portnum = ntohs(port->s_port);
 696     else if (!strcmp(service, "http"))
 697       portnum = 80;
 698     else if (!strcmp(service, "https"))
 699       portnum = 443;
 700     else if (!strcmp(service, "ipp") || !strcmp(service, "ipps"))
 701       portnum = 631;
 702     else if (!strcmp(service, "lpd"))
 703       portnum = 515;
 704     else if (!strcmp(service, "socket"))
 705       portnum = 9100;
 706     else
 707     {
 708       httpAddrFreeList(first);
 709
 710       _cupsSetError(IPP_INTERNAL_ERROR, _("Unknown service name."), 1);
 711       return (NULL);
 712     }
 713
 714     if (hostname && !_cups_strcasecmp(hostname, "localhost"))
 715     {
 716      /*
 717       * Unfortunately, some users ignore all of the warnings in the
 718       * /etc/hosts file and delete "localhost" from it. If we get here
 719       * then we were unable to resolve the name, so use the IPv6 and/or
 720       * IPv4 loopback interface addresses...
 721       */
 722
 723 #ifdef AF_INET6
 724       if (family != AF_INET)
 725       {
 726        /*
 727         * Add [::1] to the address list...
 728         */
 729
 730         temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 731         if (!temp)
 732         {
 733           _cupsSetError(IPP_INTERNAL_ERROR, strerror(errno), 0);
 734           httpAddrFreeList(first);
 735           return (NULL);
 736         }
 737
 738         temp->addr.ipv6.sin6_family            = AF_INET6;
 739         temp->addr.ipv6.sin6_port              = htons(portnum);
 740 #  ifdef WIN32
 741         temp->addr.ipv6.sin6_addr.u.Byte[15]   = 1;
 742 #  else
 743         temp->addr.ipv6.sin6_addr.s6_addr32[3] = htonl(1);
 744 #  endif /* WIN32 */
 745
 746         if (!first)
 747           first = temp;
 748
 749         addr = temp;
 750       }
 751
 752       if (family != AF_INET6)
 753 #endif /* AF_INET6 */
 754       {
 755        /*
 756         * Add 127.0.0.1 to the address list...
 757         */
 758
 759         temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 760         if (!temp)
 761         {
 762           _cupsSetError(IPP_INTERNAL_ERROR, strerror(errno), 0);
 763           httpAddrFreeList(first);
 764           return (NULL);
 765         }
 766
 767         temp->addr.ipv4.sin_family      = AF_INET;
 768         temp->addr.ipv4.sin_port        = htons(portnum);
 769         temp->addr.ipv4.sin_addr.s_addr = htonl(0x7f000001);
 770
 771         if (!first)
 772           first = temp;
 773
 774         if (addr)
 775           addr->next = temp;
 776       }
 777     }
 778     else if (!hostname)
 779     {
 780      /*
 781       * Provide one or more passive listening addresses...
 782       */
 783
 784 #ifdef AF_INET6
 785       if (family != AF_INET)
 786       {
 787        /*
 788         * Add [::] to the address list...
 789         */
 790
 791         temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 792         if (!temp)
 793         {
 794           _cupsSetError(IPP_INTERNAL_ERROR, strerror(errno), 0);
 795           httpAddrFreeList(first);
 796           return (NULL);
 797         }
 798
 799         temp->addr.ipv6.sin6_family = AF_INET6;
 800         temp->addr.ipv6.sin6_port   = htons(portnum);
 801
 802         if (!first)
 803           first = temp;
 804
 805         addr = temp;
 806       }
 807
 808       if (family != AF_INET6)
 809 #endif /* AF_INET6 */
 810       {
 811        /*
 812         * Add 0.0.0.0 to the address list...
 813         */
 814
 815         temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 816         if (!temp)
 817         {
 818           _cupsSetError(IPP_INTERNAL_ERROR, strerror(errno), 0);
 819           httpAddrFreeList(first);
 820           return (NULL);
 821         }
 822
 823         temp->addr.ipv4.sin_family = AF_INET;
 824         temp->addr.ipv4.sin_port   = htons(portnum);
 825
 826         if (!first)
 827           first = temp;
 828
 829         if (addr)
 830           addr->next = temp;
 831       }
 832     }
 833   }
 834
 835  /*
 836   * Return the address list...
 837   */
 838
 839   return (first);
 840 }
 841
 842
 843 /*
 844  * End of "$Id: http-addrlist.c 7910 2008-09-06 00:25:17Z mike $".
 845  */