cups/http-addrlist.c

   1 /*
   2  * HTTP address list routines for CUPS.
   3  *
   4  * Copyright 2007-2016 by Apple Inc.
   5  * Copyright 1997-2007 by Easy Software Products, all rights reserved.
   6  *
   7  * These coded instructions, statements, and computer programs are the
   8  * property of Apple Inc. and are protected by Federal copyright
   9  * law.  Distribution and use rights are outlined in the file "LICENSE.txt"
  10  * which should have been included with this file.  If this file is
  11  * file is missing or damaged, see the license at "http://www.cups.org/".
  12  *
  13  * This file is subject to the Apple OS-Developed Software exception.
  14  */
  15
  16 /*
  17  * Include necessary headers...
  18  */
  19
  20 #include "cups-private.h"
  21 #ifdef HAVE_RESOLV_H
  22 #  include <resolv.h>
  23 #endif /* HAVE_RESOLV_H */
  24 #ifdef HAVE_POLL
  25 #  include <poll.h>
  26 #endif /* HAVE_POLL */
  27 #ifndef WIN32
  28 #  include <fcntl.h>
  29 #endif /* WIN32 */
  30
  31
  32 /*
  33  * 'httpAddrConnect()' - Connect to any of the addresses in the list.
  34  *
  35  * @since CUPS 1.2/macOS 10.5@
  36  */
  37
  38 http_addrlist_t *                       /* O - Connected address or NULL on failure */
  39 httpAddrConnect(
  40     http_addrlist_t *addrlist,          /* I - List of potential addresses */
  41     int             *sock)              /* O - Socket */
  42 {
  43   DEBUG_printf(("httpAddrConnect(addrlist=%p, sock=%p)", (void *)addrlist, (void *)sock));
  44
  45   return (httpAddrConnect2(addrlist, sock, 30000, NULL));
  46 }
  47
  48
  49 /*
  50  * 'httpAddrConnect2()' - Connect to any of the addresses in the list with a
  51  *                        timeout and optional cancel.
  52  *
  53  * @since CUPS 1.7/macOS 10.9@
  54  */
  55
  56 http_addrlist_t *                       /* O - Connected address or NULL on failure */
  57 httpAddrConnect2(
  58     http_addrlist_t *addrlist,          /* I - List of potential addresses */
  59     int             *sock,              /* O - Socket */
  60     int             msec,               /* I - Timeout in milliseconds */
  61     int             *cancel)            /* I - Pointer to "cancel" variable */
  62 {
  63   int                   val;            /* Socket option value */
  64 #ifdef O_NONBLOCK
  65   int                   flags,          /* Socket flags */
  66                         remaining;      /* Remaining timeout */
  67   int                   i,              /* Looping var */
  68                         nfds,           /* Number of file descriptors */
  69                         fds[100],       /* Socket file descriptors */
  70                         result;         /* Result from select() or poll() */
  71   http_addrlist_t       *addrs[100];    /* Addresses */
  72 #  ifdef HAVE_POLL
  73   struct pollfd         pfds[100];      /* Polled file descriptors */
  74 #  else
  75   int                   max_fd = -1;    /* Highest file descriptor */
  76   fd_set                input_set,      /* select() input set */
  77                         output_set;     /* select() output set */
  78   struct timeval        timeout;        /* Timeout */
  79 #  endif /* HAVE_POLL */
  80 #endif /* O_NONBLOCK */
  81 #ifdef DEBUG
  82   socklen_t             len;            /* Length of value */
  83   http_addr_t           peer;           /* Peer address */
  84   char                  temp[256];      /* Temporary address string */
  85 #endif /* DEBUG */
  86
  87
  88   DEBUG_printf(("httpAddrConnect2(addrlist=%p, sock=%p, msec=%d, cancel=%p)", (void *)addrlist, (void *)sock, msec, (void *)cancel));
  89
  90   if (!sock)
  91   {
  92     errno = EINVAL;
  93     _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
  94     return (NULL);
  95   }
  96
  97   if (cancel && *cancel)
  98     return (NULL);
  99
 100   if (msec <= 0)
 101     msec = INT_MAX;
 102
 103  /*
 104   * Loop through each address until we connect or run out of addresses...
 105   */
 106
 107   nfds      = 0;
 108   remaining = msec;
 109
 110   while (remaining > 0)
 111   {
 112     if (cancel && *cancel)
 113     {
 114       while (nfds > 0)
 115       {
 116         nfds --;
 117         httpAddrClose(NULL, fds[nfds]);
 118       }
 119
 120       return (NULL);
 121     }
 122
 123     if (addrlist && nfds < (int)(sizeof(fds) / sizeof(fds[0])))
 124     {
 125      /*
 126       * Create the socket...
 127       */
 128
 129       DEBUG_printf(("2httpAddrConnect2: Trying %s:%d...", httpAddrString(&(addrlist->addr), temp, sizeof(temp)), httpAddrPort(&(addrlist->addr))));
 130
 131       if ((fds[nfds] = (int)socket(httpAddrFamily(&(addrlist->addr)), SOCK_STREAM, 0)) < 0)
 132       {
 133        /*
 134         * Don't abort yet, as this could just be an issue with the local
 135         * system not being configured with IPv4/IPv6/domain socket enabled.
 136         *
 137         * Just skip this address...
 138         */
 139
 140         addrlist = addrlist->next;
 141         continue;
 142       }
 143
 144      /*
 145       * Set options...
 146       */
 147
 148       val = 1;
 149       setsockopt(fds[nfds], SOL_SOCKET, SO_REUSEADDR, CUPS_SOCAST &val, sizeof(val));
 150
 151 #ifdef SO_REUSEPORT
 152       val = 1;
 153       setsockopt(fds[nfds], SOL_SOCKET, SO_REUSEPORT, CUPS_SOCAST &val, sizeof(val));
 154 #endif /* SO_REUSEPORT */
 155
 156 #ifdef SO_NOSIGPIPE
 157       val = 1;
 158       setsockopt(fds[nfds], SOL_SOCKET, SO_NOSIGPIPE, CUPS_SOCAST &val, sizeof(val));
 159 #endif /* SO_NOSIGPIPE */
 160
 161      /*
 162       * Using TCP_NODELAY improves responsiveness, especially on systems
 163       * with a slow loopback interface...
 164       */
 165
 166       val = 1;
 167       setsockopt(fds[nfds], IPPROTO_TCP, TCP_NODELAY, CUPS_SOCAST &val, sizeof(val));
 168
 169 #ifdef FD_CLOEXEC
 170      /*
 171       * Close this socket when starting another process...
 172       */
 173
 174       fcntl(fds[nfds], F_SETFD, FD_CLOEXEC);
 175 #endif /* FD_CLOEXEC */
 176
 177 #ifdef O_NONBLOCK
 178      /*
 179       * Do an asynchronous connect by setting the socket non-blocking...
 180       */
 181
 182       DEBUG_printf(("httpAddrConnect2: Setting non-blocking connect()"));
 183
 184       flags = fcntl(fds[nfds], F_GETFL, 0);
 185       fcntl(fds[nfds], F_SETFL, flags | O_NONBLOCK);
 186 #endif /* O_NONBLOCK */
 187
 188      /*
 189       * Then connect...
 190       */
 191
 192       if (!connect(fds[nfds], &(addrlist->addr.addr), (socklen_t)httpAddrLength(&(addrlist->addr))))
 193       {
 194         DEBUG_printf(("1httpAddrConnect2: Connected to %s:%d...", httpAddrString(&(addrlist->addr), temp, sizeof(temp)), httpAddrPort(&(addrlist->addr))));
 195
 196 #ifdef O_NONBLOCK
 197         fcntl(fds[nfds], F_SETFL, flags);
 198 #endif /* O_NONBLOCK */
 199
 200         *sock = fds[nfds];
 201
 202         while (nfds > 0)
 203         {
 204           nfds --;
 205           httpAddrClose(NULL, fds[nfds]);
 206         }
 207
 208         return (addrlist);
 209       }
 210
 211 #ifdef WIN32
 212       if (WSAGetLastError() != WSAEINPROGRESS && WSAGetLastError() != WSAEWOULDBLOCK)
 213 #else
 214       if (errno != EINPROGRESS && errno != EWOULDBLOCK)
 215 #endif /* WIN32 */
 216       {
 217         DEBUG_printf(("1httpAddrConnect2: Unable to connect to %s:%d: %s", httpAddrString(&(addrlist->addr), temp, sizeof(temp)), httpAddrPort(&(addrlist->addr)), strerror(errno)));
 218         httpAddrClose(NULL, fds[nfds]);
 219         addrlist = addrlist->next;
 220         continue;
 221       }
 222
 223       fcntl(fds[nfds], F_SETFL, flags);
 224
 225 #ifndef HAVE_POLL
 226       if (fds[nfds] > max_fd)
 227         max_fd = fds[nfds];
 228 #endif /* !HAVE_POLL */
 229
 230       addrs[nfds] = addrlist;
 231       nfds ++;
 232       addrlist = addrlist->next;
 233     }
 234
 235    /*
 236     * See if we can connect to any of the addresses so far...
 237     */
 238
 239 #ifdef O_NONBLOCK
 240     DEBUG_puts("1httpAddrConnect2: Finishing async connect()");
 241
 242     do
 243     {
 244       if (cancel && *cancel)
 245       {
 246        /*
 247         * Close this socket and return...
 248         */
 249
 250         DEBUG_puts("1httpAddrConnect2: Canceled connect()");
 251
 252         while (nfds > 0)
 253         {
 254           nfds --;
 255           httpAddrClose(NULL, fds[nfds]);
 256         }
 257
 258         *sock = -1;
 259
 260         return (NULL);
 261       }
 262
 263 #  ifdef HAVE_POLL
 264       for (i = 0; i < nfds; i ++)
 265       {
 266         pfds[i].fd     = fds[i];
 267         pfds[i].events = POLLIN | POLLOUT;
 268       }
 269
 270       result = poll(pfds, (nfds_t)nfds, addrlist ? 100 : remaining > 250 ? 250 : remaining);
 271
 272       DEBUG_printf(("1httpAddrConnect2: poll() returned %d (%d)", result, errno));
 273
 274 #  else
 275       FD_ZERO(&input_set);
 276       for (i = 0; i < nfds; i ++)
 277         FD_SET(fds[i], &input_set);
 278       output_set = input_set;
 279
 280       timeout.tv_sec  = 0;
 281       timeout.tv_usec = (addrlist ? 100 : remaining > 250 ? 250 : remaining) * 1000;
 282
 283       result = select(max_fd + 1, &input_set, &output_set, NULL, &timeout);
 284
 285       DEBUG_printf(("1httpAddrConnect2: select() returned %d (%d)", result, errno));
 286 #  endif /* HAVE_POLL */
 287     }
 288 #  ifdef WIN32
 289     while (result < 0 && (WSAGetLastError() == WSAEINTR || WSAGetLastError() == WSAEWOULDBLOCK));
 290 #  else
 291     while (result < 0 && (errno == EINTR || errno == EAGAIN));
 292 #  endif /* WIN32 */
 293
 294     if (result > 0)
 295     {
 296       for (i = 0; i < nfds; i ++)
 297       {
 298 #  ifdef HAVE_POLL
 299         DEBUG_printf(("pfds[%d].revents=%x\n", i, pfds[i].revents));
 300         if (pfds[i].revents)
 301 #  else
 302         if (FD_ISSET(fds[i], &input))
 303 #  endif /* HAVE_POLL */
 304         {
 305           *sock    = fds[i];
 306           addrlist = addrs[i];
 307
 308 #  ifdef DEBUG
 309           len   = sizeof(peer);
 310           if (!getpeername(fds[i], (struct sockaddr *)&peer, &len))
 311             DEBUG_printf(("1httpAddrConnect2: Connected to %s:%d...", httpAddrString(&peer, temp, sizeof(temp)), httpAddrPort(&peer)));
 312 #  endif /* DEBUG */
 313         }
 314         else
 315           httpAddrClose(NULL, fds[i]);
 316       }
 317
 318       return (addrlist);
 319     }
 320 #endif /* O_NONBLOCK */
 321
 322     if (addrlist)
 323       remaining -= 100;
 324     else
 325       remaining -= 250;
 326   }
 327
 328   while (nfds > 0)
 329   {
 330     nfds --;
 331     httpAddrClose(NULL, fds[nfds]);
 332   }
 333
 334 #ifdef WIN32
 335   _cupsSetError(IPP_STATUS_ERROR_SERVICE_UNAVAILABLE, "Connection failed", 0);
 336 #else
 337   _cupsSetError(IPP_STATUS_ERROR_SERVICE_UNAVAILABLE, strerror(errno), 0);
 338 #endif /* WIN32 */
 339
 340   return (NULL);
 341 }
 342
 343
 344 /*
 345  * 'httpAddrCopyList()' - Copy an address list.
 346  *
 347  * @since CUPS 1.7/macOS 10.9@
 348  */
 349
 350 http_addrlist_t *                       /* O - New address list or @code NULL@ on error */
 351 httpAddrCopyList(
 352     http_addrlist_t *src)               /* I - Source address list */
 353 {
 354   http_addrlist_t       *dst = NULL,    /* First list entry */
 355                         *prev = NULL,   /* Previous list entry */
 356                         *current = NULL;/* Current list entry */
 357
 358
 359   while (src)
 360   {
 361     if ((current = malloc(sizeof(http_addrlist_t))) == NULL)
 362     {
 363       current = dst;
 364
 365       while (current)
 366       {
 367         prev    = current;
 368         current = current->next;
 369
 370         free(prev);
 371       }
 372
 373       return (NULL);
 374     }
 375
 376     memcpy(current, src, sizeof(http_addrlist_t));
 377
 378     current->next = NULL;
 379
 380     if (prev)
 381       prev->next = current;
 382     else
 383       dst = current;
 384
 385     prev = current;
 386     src  = src->next;
 387   }
 388
 389   return (dst);
 390 }
 391
 392
 393 /*
 394  * 'httpAddrFreeList()' - Free an address list.
 395  *
 396  * @since CUPS 1.2/macOS 10.5@
 397  */
 398
 399 void
 400 httpAddrFreeList(
 401     http_addrlist_t *addrlist)          /* I - Address list to free */
 402 {
 403   http_addrlist_t       *next;          /* Next address in list */
 404
 405
 406  /*
 407   * Free each address in the list...
 408   */
 409
 410   while (addrlist)
 411   {
 412     next = addrlist->next;
 413
 414     free(addrlist);
 415
 416     addrlist = next;
 417   }
 418 }
 419
 420
 421 /*
 422  * 'httpAddrGetList()' - Get a list of addresses for a hostname.
 423  *
 424  * @since CUPS 1.2/macOS 10.5@
 425  */
 426
 427 http_addrlist_t *                       /* O - List of addresses or NULL */
 428 httpAddrGetList(const char *hostname,   /* I - Hostname, IP address, or NULL for passive listen address */
 429                 int        family,      /* I - Address family or AF_UNSPEC */
 430                 const char *service)    /* I - Service name or port number */
 431 {
 432   http_addrlist_t       *first,         /* First address in list */
 433                         *addr,          /* Current address in list */
 434                         *temp;          /* New address */
 435   _cups_globals_t       *cg = _cupsGlobals();
 436                                         /* Global data */
 437
 438
 439 #ifdef DEBUG
 440   _cups_debug_printf("httpAddrGetList(hostname=\"%s\", family=AF_%s, "
 441                      "service=\"%s\")\n",
 442                      hostname ? hostname : "(nil)",
 443                      family == AF_UNSPEC ? "UNSPEC" :
 444 #  ifdef AF_LOCAL
 445                          family == AF_LOCAL ? "LOCAL" :
 446 #  endif /* AF_LOCAL */
 447 #  ifdef AF_INET6
 448                          family == AF_INET6 ? "INET6" :
 449 #  endif /* AF_INET6 */
 450                          family == AF_INET ? "INET" : "???", service);
 451 #endif /* DEBUG */
 452
 453 #ifdef HAVE_RES_INIT
 454  /*
 455   * STR #2920: Initialize resolver after failure in cups-polld
 456   *
 457   * If the previous lookup failed, re-initialize the resolver to prevent
 458   * temporary network errors from persisting.  This *should* be handled by
 459   * the resolver libraries, but apparently the glibc folks do not agree.
 460   *
 461   * We set a flag at the end of this function if we encounter an error that
 462   * requires reinitialization of the resolver functions.  We then call
 463   * res_init() if the flag is set on the next call here or in httpAddrLookup().
 464   */
 465
 466   if (cg->need_res_init)
 467   {
 468     res_init();
 469
 470     cg->need_res_init = 0;
 471   }
 472 #endif /* HAVE_RES_INIT */
 473
 474  /*
 475   * Lookup the address the best way we can...
 476   */
 477
 478   first = addr = NULL;
 479
 480 #ifdef AF_LOCAL
 481   if (hostname && hostname[0] == '/')
 482   {
 483    /*
 484     * Domain socket address...
 485     */
 486
 487     if ((first = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t))) != NULL)
 488     {
 489       addr = first;
 490       first->addr.un.sun_family = AF_LOCAL;
 491       strlcpy(first->addr.un.sun_path, hostname, sizeof(first->addr.un.sun_path));
 492     }
 493   }
 494   else
 495 #endif /* AF_LOCAL */
 496   if (!hostname || _cups_strcasecmp(hostname, "localhost"))
 497   {
 498 #ifdef HAVE_GETADDRINFO
 499     struct addrinfo     hints,          /* Address lookup hints */
 500                         *results,       /* Address lookup results */
 501                         *current;       /* Current result */
 502     char                ipv6[64],       /* IPv6 address */
 503                         *ipv6zone;      /* Pointer to zone separator */
 504     int                 ipv6len;        /* Length of IPv6 address */
 505     int                 error;          /* getaddrinfo() error */
 506
 507
 508    /*
 509     * Lookup the address as needed...
 510     */
 511
 512     memset(&hints, 0, sizeof(hints));
 513     hints.ai_family   = family;
 514     hints.ai_flags    = hostname ? 0 : AI_PASSIVE;
 515     hints.ai_socktype = SOCK_STREAM;
 516
 517     if (hostname && *hostname == '[')
 518     {
 519      /*
 520       * Remove brackets from numeric IPv6 address...
 521       */
 522
 523       if (!strncmp(hostname, "[v1.", 4))
 524       {
 525        /*
 526         * Copy the newer address format which supports link-local addresses...
 527         */
 528
 529         strlcpy(ipv6, hostname + 4, sizeof(ipv6));
 530         if ((ipv6len = (int)strlen(ipv6) - 1) >= 0 && ipv6[ipv6len] == ']')
 531         {
 532           ipv6[ipv6len] = '\0';
 533           hostname      = ipv6;
 534
 535          /*
 536           * Convert "+zone" in address to "%zone"...
 537           */
 538
 539           if ((ipv6zone = strrchr(ipv6, '+')) != NULL)
 540             *ipv6zone = '%';
 541         }
 542       }
 543       else
 544       {
 545        /*
 546         * Copy the regular non-link-local IPv6 address...
 547         */
 548
 549         strlcpy(ipv6, hostname + 1, sizeof(ipv6));
 550         if ((ipv6len = (int)strlen(ipv6) - 1) >= 0 && ipv6[ipv6len] == ']')
 551         {
 552           ipv6[ipv6len] = '\0';
 553           hostname      = ipv6;
 554         }
 555       }
 556     }
 557
 558     if ((error = getaddrinfo(hostname, service, &hints, &results)) == 0)
 559     {
 560      /*
 561       * Copy the results to our own address list structure...
 562       */
 563
 564       for (current = results; current; current = current->ai_next)
 565         if (current->ai_family == AF_INET || current->ai_family == AF_INET6)
 566         {
 567          /*
 568           * Copy the address over...
 569           */
 570
 571           temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 572           if (!temp)
 573           {
 574             httpAddrFreeList(first);
 575             _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
 576             return (NULL);
 577           }
 578
 579           if (current->ai_family == AF_INET6)
 580             memcpy(&(temp->addr.ipv6), current->ai_addr,
 581                    sizeof(temp->addr.ipv6));
 582           else
 583             memcpy(&(temp->addr.ipv4), current->ai_addr,
 584                    sizeof(temp->addr.ipv4));
 585
 586          /*
 587           * Append the address to the list...
 588           */
 589
 590           if (!first)
 591             first = temp;
 592
 593           if (addr)
 594             addr->next = temp;
 595
 596           addr = temp;
 597         }
 598
 599      /*
 600       * Free the results from getaddrinfo()...
 601       */
 602
 603       freeaddrinfo(results);
 604     }
 605     else
 606     {
 607       if (error == EAI_FAIL)
 608         cg->need_res_init = 1;
 609
 610       _cupsSetError(IPP_STATUS_ERROR_INTERNAL, gai_strerror(error), 0);
 611     }
 612
 613 #else
 614     if (hostname)
 615     {
 616       int               i;              /* Looping vars */
 617       unsigned          ip[4];          /* IPv4 address components */
 618       const char        *ptr;           /* Pointer into hostname */
 619       struct hostent    *host;          /* Result of lookup */
 620       struct servent    *port;          /* Port number for service */
 621       int               portnum;        /* Port number */
 622
 623
 624      /*
 625       * Lookup the service...
 626       */
 627
 628       if (!service)
 629         portnum = 0;
 630       else if (isdigit(*service & 255))
 631         portnum = atoi(service);
 632       else if ((port = getservbyname(service, NULL)) != NULL)
 633         portnum = ntohs(port->s_port);
 634       else if (!strcmp(service, "http"))
 635         portnum = 80;
 636       else if (!strcmp(service, "https"))
 637         portnum = 443;
 638       else if (!strcmp(service, "ipp") || !strcmp(service, "ipps"))
 639         portnum = 631;
 640       else if (!strcmp(service, "lpd"))
 641         portnum = 515;
 642       else if (!strcmp(service, "socket"))
 643         portnum = 9100;
 644       else
 645         return (NULL);
 646
 647      /*
 648       * This code is needed because some operating systems have a
 649       * buggy implementation of gethostbyname() that does not support
 650       * IPv4 addresses.  If the hostname string is an IPv4 address, then
 651       * sscanf() is used to extract the IPv4 components.  We then pack
 652       * the components into an IPv4 address manually, since the
 653       * inet_aton() function is deprecated.  We use the htonl() macro
 654       * to get the right byte order for the address.
 655       */
 656
 657       for (ptr = hostname; isdigit(*ptr & 255) || *ptr == '.'; ptr ++);
 658
 659       if (!*ptr)
 660       {
 661        /*
 662         * We have an IPv4 address; break it up and create an IPv4 address...
 663         */
 664
 665         if (sscanf(hostname, "%u.%u.%u.%u", ip, ip + 1, ip + 2, ip + 3) == 4 &&
 666             ip[0] <= 255 && ip[1] <= 255 && ip[2] <= 255 && ip[3] <= 255)
 667         {
 668           first = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 669           if (!first)
 670             return (NULL);
 671
 672           first->addr.ipv4.sin_family = AF_INET;
 673           first->addr.ipv4.sin_addr.s_addr = htonl((((((((unsigned)ip[0] << 8) |
 674                                                        (unsigned)ip[1]) << 8) |
 675                                                      (unsigned)ip[2]) << 8) |
 676                                                    (unsigned)ip[3]));
 677           first->addr.ipv4.sin_port = htons(portnum);
 678         }
 679       }
 680       else if ((host = gethostbyname(hostname)) != NULL &&
 681 #  ifdef AF_INET6
 682                (host->h_addrtype == AF_INET || host->h_addrtype == AF_INET6))
 683 #  else
 684                host->h_addrtype == AF_INET)
 685 #  endif /* AF_INET6 */
 686       {
 687         for (i = 0; host->h_addr_list[i]; i ++)
 688         {
 689          /*
 690           * Copy the address over...
 691           */
 692
 693           temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 694           if (!temp)
 695           {
 696             httpAddrFreeList(first);
 697             return (NULL);
 698           }
 699
 700 #  ifdef AF_INET6
 701           if (host->h_addrtype == AF_INET6)
 702           {
 703             temp->addr.ipv6.sin6_family = AF_INET6;
 704             memcpy(&(temp->addr.ipv6.sin6_addr), host->h_addr_list[i],
 705                    sizeof(temp->addr.ipv6));
 706             temp->addr.ipv6.sin6_port = htons(portnum);
 707           }
 708           else
 709 #  endif /* AF_INET6 */
 710           {
 711             temp->addr.ipv4.sin_family = AF_INET;
 712             memcpy(&(temp->addr.ipv4.sin_addr), host->h_addr_list[i],
 713                    sizeof(temp->addr.ipv4));
 714             temp->addr.ipv4.sin_port = htons(portnum);
 715           }
 716
 717          /*
 718           * Append the address to the list...
 719           */
 720
 721           if (!first)
 722             first = temp;
 723
 724           if (addr)
 725             addr->next = temp;
 726
 727           addr = temp;
 728         }
 729       }
 730       else
 731       {
 732         if (h_errno == NO_RECOVERY)
 733           cg->need_res_init = 1;
 734
 735         _cupsSetError(IPP_STATUS_ERROR_INTERNAL, hstrerror(h_errno), 0);
 736       }
 737     }
 738 #endif /* HAVE_GETADDRINFO */
 739   }
 740
 741  /*
 742   * Detect some common errors and handle them sanely...
 743   */
 744
 745   if (!addr && (!hostname || !_cups_strcasecmp(hostname, "localhost")))
 746   {
 747     struct servent      *port;          /* Port number for service */
 748     int                 portnum;        /* Port number */
 749
 750
 751    /*
 752     * Lookup the service...
 753     */
 754
 755     if (!service)
 756       portnum = 0;
 757     else if (isdigit(*service & 255))
 758       portnum = atoi(service);
 759     else if ((port = getservbyname(service, NULL)) != NULL)
 760       portnum = ntohs(port->s_port);
 761     else if (!strcmp(service, "http"))
 762       portnum = 80;
 763     else if (!strcmp(service, "https"))
 764       portnum = 443;
 765     else if (!strcmp(service, "ipp") || !strcmp(service, "ipps"))
 766       portnum = 631;
 767     else if (!strcmp(service, "lpd"))
 768       portnum = 515;
 769     else if (!strcmp(service, "socket"))
 770       portnum = 9100;
 771     else
 772     {
 773       httpAddrFreeList(first);
 774
 775       _cupsSetError(IPP_STATUS_ERROR_INTERNAL, _("Unknown service name."), 1);
 776       return (NULL);
 777     }
 778
 779     if (hostname && !_cups_strcasecmp(hostname, "localhost"))
 780     {
 781      /*
 782       * Unfortunately, some users ignore all of the warnings in the
 783       * /etc/hosts file and delete "localhost" from it. If we get here
 784       * then we were unable to resolve the name, so use the IPv6 and/or
 785       * IPv4 loopback interface addresses...
 786       */
 787
 788 #ifdef AF_INET6
 789       if (family != AF_INET)
 790       {
 791        /*
 792         * Add [::1] to the address list...
 793         */
 794
 795         temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 796         if (!temp)
 797         {
 798           _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
 799           httpAddrFreeList(first);
 800           return (NULL);
 801         }
 802
 803         temp->addr.ipv6.sin6_family            = AF_INET6;
 804         temp->addr.ipv6.sin6_port              = htons(portnum);
 805 #  ifdef WIN32
 806         temp->addr.ipv6.sin6_addr.u.Byte[15]   = 1;
 807 #  else
 808         temp->addr.ipv6.sin6_addr.s6_addr32[3] = htonl(1);
 809 #  endif /* WIN32 */
 810
 811         if (!first)
 812           first = temp;
 813
 814         addr = temp;
 815       }
 816
 817       if (family != AF_INET6)
 818 #endif /* AF_INET6 */
 819       {
 820        /*
 821         * Add 127.0.0.1 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.ipv4.sin_family      = AF_INET;
 833         temp->addr.ipv4.sin_port        = htons(portnum);
 834         temp->addr.ipv4.sin_addr.s_addr = htonl(0x7f000001);
 835
 836         if (!first)
 837           first = temp;
 838
 839         if (addr)
 840           addr->next = temp;
 841       }
 842     }
 843     else if (!hostname)
 844     {
 845      /*
 846       * Provide one or more passive listening addresses...
 847       */
 848
 849 #ifdef AF_INET6
 850       if (family != AF_INET)
 851       {
 852        /*
 853         * Add [::] to the address list...
 854         */
 855
 856         temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 857         if (!temp)
 858         {
 859           _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
 860           httpAddrFreeList(first);
 861           return (NULL);
 862         }
 863
 864         temp->addr.ipv6.sin6_family = AF_INET6;
 865         temp->addr.ipv6.sin6_port   = htons(portnum);
 866
 867         if (!first)
 868           first = temp;
 869
 870         addr = temp;
 871       }
 872
 873       if (family != AF_INET6)
 874 #endif /* AF_INET6 */
 875       {
 876        /*
 877         * Add 0.0.0.0 to the address list...
 878         */
 879
 880         temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 881         if (!temp)
 882         {
 883           _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
 884           httpAddrFreeList(first);
 885           return (NULL);
 886         }
 887
 888         temp->addr.ipv4.sin_family = AF_INET;
 889         temp->addr.ipv4.sin_port   = htons(portnum);
 890
 891         if (!first)
 892           first = temp;
 893
 894         if (addr)
 895           addr->next = temp;
 896       }
 897     }
 898   }
 899
 900  /*
 901   * Return the address list...
 902   */
 903
 904   return (first);
 905 }