cups/http-addrlist.c

   1 /*
   2  * HTTP address list routines for CUPS.
   3  *
   4  * Copyright 2007-2018 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  * 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@ @exclude all@
  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 #ifndef _WIN32
  65   int                   flags;          /* Socket flags */
  66 #endif /* !_WIN32 */
  67   int                   remaining;      /* Remaining timeout */
  68   int                   i, j,           /* Looping vars */
  69                         nfds,           /* Number of file descriptors */
  70                         fds[100],       /* Socket file descriptors */
  71                         result;         /* Result from select() or poll() */
  72   http_addrlist_t       *addrs[100];    /* Addresses */
  73 #ifndef HAVE_POLL
  74   int                   max_fd = -1;    /* Highest file descriptor */
  75 #endif /* !HAVE_POLL */
  76 #ifdef O_NONBLOCK
  77 #  ifdef HAVE_POLL
  78   struct pollfd         pfds[100];      /* Polled file descriptors */
  79 #  else
  80   fd_set                input_set,      /* select() input set */
  81                         output_set,     /* select() output set */
  82                         error_set;      /* select() error set */
  83   struct timeval        timeout;        /* Timeout */
  84 #  endif /* HAVE_POLL */
  85 #endif /* O_NONBLOCK */
  86 #ifdef DEBUG
  87   socklen_t             len;            /* Length of value */
  88   http_addr_t           peer;           /* Peer address */
  89   char                  temp[256];      /* Temporary address string */
  90 #endif /* DEBUG */
  91
  92
  93   DEBUG_printf(("httpAddrConnect2(addrlist=%p, sock=%p, msec=%d, cancel=%p)", (void *)addrlist, (void *)sock, msec, (void *)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)
 106     msec = INT_MAX;
 107
 108  /*
 109   * Loop through each address until we connect or run out of addresses...
 110   */
 111
 112   nfds      = 0;
 113   remaining = msec;
 114
 115   while (remaining > 0)
 116   {
 117     if (cancel && *cancel)
 118     {
 119       while (nfds > 0)
 120       {
 121         nfds --;
 122         httpAddrClose(NULL, fds[nfds]);
 123       }
 124
 125       return (NULL);
 126     }
 127
 128     if (addrlist && nfds < (int)(sizeof(fds) / sizeof(fds[0])))
 129     {
 130      /*
 131       * Create the socket...
 132       */
 133
 134       DEBUG_printf(("2httpAddrConnect2: Trying %s:%d...", httpAddrString(&(addrlist->addr), temp, sizeof(temp)), httpAddrPort(&(addrlist->addr))));
 135
 136       if ((fds[nfds] = (int)socket(httpAddrFamily(&(addrlist->addr)), SOCK_STREAM, 0)) < 0)
 137       {
 138        /*
 139         * Don't abort yet, as this could just be an issue with the local
 140         * system not being configured with IPv4/IPv6/domain socket enabled.
 141         *
 142         * Just skip this address...
 143         */
 144
 145         addrlist = addrlist->next;
 146         continue;
 147       }
 148
 149      /*
 150       * Set options...
 151       */
 152
 153       val = 1;
 154       setsockopt(fds[nfds], SOL_SOCKET, SO_REUSEADDR, CUPS_SOCAST &val, sizeof(val));
 155
 156 #ifdef SO_REUSEPORT
 157       val = 1;
 158       setsockopt(fds[nfds], SOL_SOCKET, SO_REUSEPORT, CUPS_SOCAST &val, sizeof(val));
 159 #endif /* SO_REUSEPORT */
 160
 161 #ifdef SO_NOSIGPIPE
 162       val = 1;
 163       setsockopt(fds[nfds], SOL_SOCKET, SO_NOSIGPIPE, CUPS_SOCAST &val, sizeof(val));
 164 #endif /* SO_NOSIGPIPE */
 165
 166      /*
 167       * Using TCP_NODELAY improves responsiveness, especially on systems
 168       * with a slow loopback interface...
 169       */
 170
 171       val = 1;
 172       setsockopt(fds[nfds], IPPROTO_TCP, TCP_NODELAY, CUPS_SOCAST &val, sizeof(val));
 173
 174 #ifdef FD_CLOEXEC
 175      /*
 176       * Close this socket when starting another process...
 177       */
 178
 179       fcntl(fds[nfds], F_SETFD, FD_CLOEXEC);
 180 #endif /* FD_CLOEXEC */
 181
 182 #ifdef O_NONBLOCK
 183      /*
 184       * Do an asynchronous connect by setting the socket non-blocking...
 185       */
 186
 187       DEBUG_printf(("httpAddrConnect2: Setting non-blocking connect()"));
 188
 189       flags = fcntl(fds[nfds], F_GETFL, 0);
 190       fcntl(fds[nfds], F_SETFL, flags | O_NONBLOCK);
 191 #endif /* O_NONBLOCK */
 192
 193      /*
 194       * Then connect...
 195       */
 196
 197       if (!connect(fds[nfds], &(addrlist->addr.addr), (socklen_t)httpAddrLength(&(addrlist->addr))))
 198       {
 199         DEBUG_printf(("1httpAddrConnect2: Connected to %s:%d...", httpAddrString(&(addrlist->addr), temp, sizeof(temp)), httpAddrPort(&(addrlist->addr))));
 200
 201 #ifdef O_NONBLOCK
 202         fcntl(fds[nfds], F_SETFL, flags);
 203 #endif /* O_NONBLOCK */
 204
 205         *sock = fds[nfds];
 206
 207         while (nfds > 0)
 208         {
 209           nfds --;
 210           httpAddrClose(NULL, fds[nfds]);
 211         }
 212
 213         return (addrlist);
 214       }
 215
 216 #ifdef _WIN32
 217       if (WSAGetLastError() != WSAEINPROGRESS && WSAGetLastError() != WSAEWOULDBLOCK)
 218 #else
 219       if (errno != EINPROGRESS && errno != EWOULDBLOCK)
 220 #endif /* _WIN32 */
 221       {
 222         DEBUG_printf(("1httpAddrConnect2: Unable to connect to %s:%d: %s", httpAddrString(&(addrlist->addr), temp, sizeof(temp)), httpAddrPort(&(addrlist->addr)), strerror(errno)));
 223         httpAddrClose(NULL, fds[nfds]);
 224         addrlist = addrlist->next;
 225         continue;
 226       }
 227
 228 #ifndef _WIN32
 229       fcntl(fds[nfds], F_SETFL, flags);
 230 #endif /* !_WIN32 */
 231
 232 #ifndef HAVE_POLL
 233       if (fds[nfds] > max_fd)
 234         max_fd = fds[nfds];
 235 #endif /* !HAVE_POLL */
 236
 237       addrs[nfds] = addrlist;
 238       nfds ++;
 239       addrlist = addrlist->next;
 240     }
 241
 242     if (!addrlist && nfds == 0)
 243       break;
 244
 245    /*
 246     * See if we can connect to any of the addresses so far...
 247     */
 248
 249 #ifdef O_NONBLOCK
 250     DEBUG_puts("1httpAddrConnect2: Finishing async connect()");
 251
 252     do
 253     {
 254       if (cancel && *cancel)
 255       {
 256        /*
 257         * Close this socket and return...
 258         */
 259
 260         DEBUG_puts("1httpAddrConnect2: Canceled connect()");
 261
 262         while (nfds > 0)
 263         {
 264           nfds --;
 265           httpAddrClose(NULL, fds[nfds]);
 266         }
 267
 268         *sock = -1;
 269
 270         return (NULL);
 271       }
 272
 273 #  ifdef HAVE_POLL
 274       for (i = 0; i < nfds; i ++)
 275       {
 276         pfds[i].fd     = fds[i];
 277         pfds[i].events = POLLIN | POLLOUT;
 278       }
 279
 280       result = poll(pfds, (nfds_t)nfds, addrlist ? 100 : remaining > 250 ? 250 : remaining);
 281
 282       DEBUG_printf(("1httpAddrConnect2: poll() returned %d (%d)", result, errno));
 283
 284 #  else
 285       FD_ZERO(&input_set);
 286       for (i = 0; i < nfds; i ++)
 287         FD_SET(fds[i], &input_set);
 288       output_set = input_set;
 289       error_set  = input_set;
 290
 291       timeout.tv_sec  = 0;
 292       timeout.tv_usec = (addrlist ? 100 : remaining > 250 ? 250 : remaining) * 1000;
 293
 294       result = select(max_fd + 1, &input_set, &output_set, &error_set, &timeout);
 295
 296       DEBUG_printf(("1httpAddrConnect2: select() returned %d (%d)", result, errno));
 297 #  endif /* HAVE_POLL */
 298     }
 299 #  ifdef _WIN32
 300     while (result < 0 && (WSAGetLastError() == WSAEINTR || WSAGetLastError() == WSAEWOULDBLOCK));
 301 #  else
 302     while (result < 0 && (errno == EINTR || errno == EAGAIN));
 303 #  endif /* _WIN32 */
 304
 305     if (result > 0)
 306     {
 307       http_addrlist_t *connaddr = NULL; /* Connected address, if any */
 308
 309       for (i = 0; i < nfds; i ++)
 310       {
 311 #  ifdef HAVE_POLL
 312         DEBUG_printf(("pfds[%d].revents=%x\n", i, pfds[i].revents));
 313         if (pfds[i].revents && !(pfds[i].revents & (POLLERR | POLLHUP)))
 314 #  else
 315         if (FD_ISSET(fds[i], &input_set) && !FD_ISSET(fds[i], &error_set))
 316 #  endif /* HAVE_POLL */
 317         {
 318           *sock    = fds[i];
 319           connaddr = addrs[i];
 320
 321 #  ifdef DEBUG
 322           len   = sizeof(peer);
 323           if (!getpeername(fds[i], (struct sockaddr *)&peer, &len))
 324             DEBUG_printf(("1httpAddrConnect2: Connected to %s:%d...", httpAddrString(&peer, temp, sizeof(temp)), httpAddrPort(&peer)));
 325 #  endif /* DEBUG */
 326
 327           break;
 328         }
 329 #  ifdef HAVE_POLL
 330         else if (pfds[i].revents & (POLLERR | POLLHUP))
 331 #  else
 332         else if (FD_ISSET(fds[i], &error_set))
 333 #  endif /* HAVE_POLL */
 334         {
 335          /*
 336           * Error on socket, remove from the "pool"...
 337           */
 338
 339           httpAddrClose(NULL, fds[i]);
 340           nfds --;
 341           if (i < nfds)
 342           {
 343             memmove(fds + i, fds + i + 1, (size_t)(nfds - i) * (sizeof(fds[0])));
 344             memmove(addrs + i, addrs + i + 1, (size_t)(nfds - i) * (sizeof(addrs[0])));
 345           }
 346           i --;
 347         }
 348       }
 349
 350       if (connaddr)
 351       {
 352        /*
 353         * Connected on one address, close all of the other sockets we have so
 354         * far and return...
 355         */
 356
 357         for (j = 0; j < i; j ++)
 358           httpAddrClose(NULL, fds[j]);
 359
 360         for (j ++; j < nfds; j ++)
 361           httpAddrClose(NULL, fds[j]);
 362
 363         return (connaddr);
 364       }
 365     }
 366 #endif /* O_NONBLOCK */
 367
 368     if (addrlist)
 369       remaining -= 100;
 370     else
 371       remaining -= 250;
 372   }
 373
 374   while (nfds > 0)
 375   {
 376     nfds --;
 377     httpAddrClose(NULL, fds[nfds]);
 378   }
 379
 380 #ifdef _WIN32
 381   _cupsSetError(IPP_STATUS_ERROR_SERVICE_UNAVAILABLE, "Connection failed", 0);
 382 #else
 383   _cupsSetError(IPP_STATUS_ERROR_SERVICE_UNAVAILABLE, strerror(errno), 0);
 384 #endif /* _WIN32 */
 385
 386   return (NULL);
 387 }
 388
 389
 390 /*
 391  * 'httpAddrCopyList()' - Copy an address list.
 392  *
 393  * @since CUPS 1.7/macOS 10.9@
 394  */
 395
 396 http_addrlist_t *                       /* O - New address list or @code NULL@ on error */
 397 httpAddrCopyList(
 398     http_addrlist_t *src)               /* I - Source address list */
 399 {
 400   http_addrlist_t       *dst = NULL,    /* First list entry */
 401                         *prev = NULL,   /* Previous list entry */
 402                         *current = NULL;/* Current list entry */
 403
 404
 405   while (src)
 406   {
 407     if ((current = malloc(sizeof(http_addrlist_t))) == NULL)
 408     {
 409       current = dst;
 410
 411       while (current)
 412       {
 413         prev    = current;
 414         current = current->next;
 415
 416         free(prev);
 417       }
 418
 419       return (NULL);
 420     }
 421
 422     memcpy(current, src, sizeof(http_addrlist_t));
 423
 424     current->next = NULL;
 425
 426     if (prev)
 427       prev->next = current;
 428     else
 429       dst = current;
 430
 431     prev = current;
 432     src  = src->next;
 433   }
 434
 435   return (dst);
 436 }
 437
 438
 439 /*
 440  * 'httpAddrFreeList()' - Free an address list.
 441  *
 442  * @since CUPS 1.2/macOS 10.5@
 443  */
 444
 445 void
 446 httpAddrFreeList(
 447     http_addrlist_t *addrlist)          /* I - Address list to free */
 448 {
 449   http_addrlist_t       *next;          /* Next address in list */
 450
 451
 452  /*
 453   * Free each address in the list...
 454   */
 455
 456   while (addrlist)
 457   {
 458     next = addrlist->next;
 459
 460     free(addrlist);
 461
 462     addrlist = next;
 463   }
 464 }
 465
 466
 467 /*
 468  * 'httpAddrGetList()' - Get a list of addresses for a hostname.
 469  *
 470  * @since CUPS 1.2/macOS 10.5@
 471  */
 472
 473 http_addrlist_t *                       /* O - List of addresses or NULL */
 474 httpAddrGetList(const char *hostname,   /* I - Hostname, IP address, or NULL for passive listen address */
 475                 int        family,      /* I - Address family or AF_UNSPEC */
 476                 const char *service)    /* I - Service name or port number */
 477 {
 478   http_addrlist_t       *first,         /* First address in list */
 479                         *addr,          /* Current address in list */
 480                         *temp;          /* New address */
 481   _cups_globals_t       *cg = _cupsGlobals();
 482                                         /* Global data */
 483
 484
 485 #ifdef DEBUG
 486   _cups_debug_printf("httpAddrGetList(hostname=\"%s\", family=AF_%s, "
 487                      "service=\"%s\")\n",
 488                      hostname ? hostname : "(nil)",
 489                      family == AF_UNSPEC ? "UNSPEC" :
 490 #  ifdef AF_LOCAL
 491                          family == AF_LOCAL ? "LOCAL" :
 492 #  endif /* AF_LOCAL */
 493 #  ifdef AF_INET6
 494                          family == AF_INET6 ? "INET6" :
 495 #  endif /* AF_INET6 */
 496                          family == AF_INET ? "INET" : "???", service);
 497 #endif /* DEBUG */
 498
 499 #ifdef HAVE_RES_INIT
 500  /*
 501   * STR #2920: Initialize resolver after failure in cups-polld
 502   *
 503   * If the previous lookup failed, re-initialize the resolver to prevent
 504   * temporary network errors from persisting.  This *should* be handled by
 505   * the resolver libraries, but apparently the glibc folks do not agree.
 506   *
 507   * We set a flag at the end of this function if we encounter an error that
 508   * requires reinitialization of the resolver functions.  We then call
 509   * res_init() if the flag is set on the next call here or in httpAddrLookup().
 510   */
 511
 512   if (cg->need_res_init)
 513   {
 514     res_init();
 515
 516     cg->need_res_init = 0;
 517   }
 518 #endif /* HAVE_RES_INIT */
 519
 520  /*
 521   * Lookup the address the best way we can...
 522   */
 523
 524   first = addr = NULL;
 525
 526 #ifdef AF_LOCAL
 527   if (hostname && hostname[0] == '/')
 528   {
 529    /*
 530     * Domain socket address...
 531     */
 532
 533     if ((first = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t))) != NULL)
 534     {
 535       addr = first;
 536       first->addr.un.sun_family = AF_LOCAL;
 537       strlcpy(first->addr.un.sun_path, hostname, sizeof(first->addr.un.sun_path));
 538     }
 539   }
 540   else
 541 #endif /* AF_LOCAL */
 542   if (!hostname || _cups_strcasecmp(hostname, "localhost"))
 543   {
 544 #ifdef HAVE_GETADDRINFO
 545     struct addrinfo     hints,          /* Address lookup hints */
 546                         *results,       /* Address lookup results */
 547                         *current;       /* Current result */
 548     char                ipv6[64],       /* IPv6 address */
 549                         *ipv6zone;      /* Pointer to zone separator */
 550     int                 ipv6len;        /* Length of IPv6 address */
 551     int                 error;          /* getaddrinfo() error */
 552
 553
 554    /*
 555     * Lookup the address as needed...
 556     */
 557
 558     memset(&hints, 0, sizeof(hints));
 559     hints.ai_family   = family;
 560     hints.ai_flags    = hostname ? 0 : AI_PASSIVE;
 561     hints.ai_socktype = SOCK_STREAM;
 562
 563     if (hostname && *hostname == '[')
 564     {
 565      /*
 566       * Remove brackets from numeric IPv6 address...
 567       */
 568
 569       if (!strncmp(hostname, "[v1.", 4))
 570       {
 571        /*
 572         * Copy the newer address format which supports link-local addresses...
 573         */
 574
 575         strlcpy(ipv6, hostname + 4, sizeof(ipv6));
 576         if ((ipv6len = (int)strlen(ipv6) - 1) >= 0 && ipv6[ipv6len] == ']')
 577         {
 578           ipv6[ipv6len] = '\0';
 579           hostname      = ipv6;
 580
 581          /*
 582           * Convert "+zone" in address to "%zone"...
 583           */
 584
 585           if ((ipv6zone = strrchr(ipv6, '+')) != NULL)
 586             *ipv6zone = '%';
 587         }
 588       }
 589       else
 590       {
 591        /*
 592         * Copy the regular non-link-local IPv6 address...
 593         */
 594
 595         strlcpy(ipv6, hostname + 1, sizeof(ipv6));
 596         if ((ipv6len = (int)strlen(ipv6) - 1) >= 0 && ipv6[ipv6len] == ']')
 597         {
 598           ipv6[ipv6len] = '\0';
 599           hostname      = ipv6;
 600         }
 601       }
 602     }
 603
 604     if ((error = getaddrinfo(hostname, service, &hints, &results)) == 0)
 605     {
 606      /*
 607       * Copy the results to our own address list structure...
 608       */
 609
 610       for (current = results; current; current = current->ai_next)
 611         if (current->ai_family == AF_INET || current->ai_family == AF_INET6)
 612         {
 613          /*
 614           * Copy the address over...
 615           */
 616
 617           temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 618           if (!temp)
 619           {
 620             httpAddrFreeList(first);
 621             freeaddrinfo(results);
 622             _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
 623             return (NULL);
 624           }
 625
 626           if (current->ai_family == AF_INET6)
 627             memcpy(&(temp->addr.ipv6), current->ai_addr,
 628                    sizeof(temp->addr.ipv6));
 629           else
 630             memcpy(&(temp->addr.ipv4), current->ai_addr,
 631                    sizeof(temp->addr.ipv4));
 632
 633          /*
 634           * Append the address to the list...
 635           */
 636
 637           if (!first)
 638             first = temp;
 639
 640           if (addr)
 641             addr->next = temp;
 642
 643           addr = temp;
 644         }
 645
 646      /*
 647       * Free the results from getaddrinfo()...
 648       */
 649
 650       freeaddrinfo(results);
 651     }
 652     else
 653     {
 654       if (error == EAI_FAIL)
 655         cg->need_res_init = 1;
 656
 657       _cupsSetError(IPP_STATUS_ERROR_INTERNAL, gai_strerror(error), 0);
 658     }
 659
 660 #else
 661     if (hostname)
 662     {
 663       int               i;              /* Looping vars */
 664       unsigned          ip[4];          /* IPv4 address components */
 665       const char        *ptr;           /* Pointer into hostname */
 666       struct hostent    *host;          /* Result of lookup */
 667       struct servent    *port;          /* Port number for service */
 668       int               portnum;        /* Port number */
 669
 670
 671      /*
 672       * Lookup the service...
 673       */
 674
 675       if (!service)
 676         portnum = 0;
 677       else if (isdigit(*service & 255))
 678         portnum = atoi(service);
 679       else if ((port = getservbyname(service, NULL)) != NULL)
 680         portnum = ntohs(port->s_port);
 681       else if (!strcmp(service, "http"))
 682         portnum = 80;
 683       else if (!strcmp(service, "https"))
 684         portnum = 443;
 685       else if (!strcmp(service, "ipp") || !strcmp(service, "ipps"))
 686         portnum = 631;
 687       else if (!strcmp(service, "lpd"))
 688         portnum = 515;
 689       else if (!strcmp(service, "socket"))
 690         portnum = 9100;
 691       else
 692         return (NULL);
 693
 694      /*
 695       * This code is needed because some operating systems have a
 696       * buggy implementation of gethostbyname() that does not support
 697       * IPv4 addresses.  If the hostname string is an IPv4 address, then
 698       * sscanf() is used to extract the IPv4 components.  We then pack
 699       * the components into an IPv4 address manually, since the
 700       * inet_aton() function is deprecated.  We use the htonl() macro
 701       * to get the right byte order for the address.
 702       */
 703
 704       for (ptr = hostname; isdigit(*ptr & 255) || *ptr == '.'; ptr ++);
 705
 706       if (!*ptr)
 707       {
 708        /*
 709         * We have an IPv4 address; break it up and create an IPv4 address...
 710         */
 711
 712         if (sscanf(hostname, "%u.%u.%u.%u", ip, ip + 1, ip + 2, ip + 3) == 4 &&
 713             ip[0] <= 255 && ip[1] <= 255 && ip[2] <= 255 && ip[3] <= 255)
 714         {
 715           first = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 716           if (!first)
 717             return (NULL);
 718
 719           first->addr.ipv4.sin_family = AF_INET;
 720           first->addr.ipv4.sin_addr.s_addr = htonl((((((((unsigned)ip[0] << 8) |
 721                                                        (unsigned)ip[1]) << 8) |
 722                                                      (unsigned)ip[2]) << 8) |
 723                                                    (unsigned)ip[3]));
 724           first->addr.ipv4.sin_port = htons(portnum);
 725         }
 726       }
 727       else if ((host = gethostbyname(hostname)) != NULL &&
 728 #  ifdef AF_INET6
 729                (host->h_addrtype == AF_INET || host->h_addrtype == AF_INET6))
 730 #  else
 731                host->h_addrtype == AF_INET)
 732 #  endif /* AF_INET6 */
 733       {
 734         for (i = 0; host->h_addr_list[i]; i ++)
 735         {
 736          /*
 737           * Copy the address over...
 738           */
 739
 740           temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 741           if (!temp)
 742           {
 743             httpAddrFreeList(first);
 744             return (NULL);
 745           }
 746
 747 #  ifdef AF_INET6
 748           if (host->h_addrtype == AF_INET6)
 749           {
 750             temp->addr.ipv6.sin6_family = AF_INET6;
 751             memcpy(&(temp->addr.ipv6.sin6_addr), host->h_addr_list[i],
 752                    sizeof(temp->addr.ipv6));
 753             temp->addr.ipv6.sin6_port = htons(portnum);
 754           }
 755           else
 756 #  endif /* AF_INET6 */
 757           {
 758             temp->addr.ipv4.sin_family = AF_INET;
 759             memcpy(&(temp->addr.ipv4.sin_addr), host->h_addr_list[i],
 760                    sizeof(temp->addr.ipv4));
 761             temp->addr.ipv4.sin_port = htons(portnum);
 762           }
 763
 764          /*
 765           * Append the address to the list...
 766           */
 767
 768           if (!first)
 769             first = temp;
 770
 771           if (addr)
 772             addr->next = temp;
 773
 774           addr = temp;
 775         }
 776       }
 777       else
 778       {
 779         if (h_errno == NO_RECOVERY)
 780           cg->need_res_init = 1;
 781
 782         _cupsSetError(IPP_STATUS_ERROR_INTERNAL, hstrerror(h_errno), 0);
 783       }
 784     }
 785 #endif /* HAVE_GETADDRINFO */
 786   }
 787
 788  /*
 789   * Detect some common errors and handle them sanely...
 790   */
 791
 792   if (!addr && (!hostname || !_cups_strcasecmp(hostname, "localhost")))
 793   {
 794     struct servent      *port;          /* Port number for service */
 795     int                 portnum;        /* Port number */
 796
 797
 798    /*
 799     * Lookup the service...
 800     */
 801
 802     if (!service)
 803       portnum = 0;
 804     else if (isdigit(*service & 255))
 805       portnum = atoi(service);
 806     else if ((port = getservbyname(service, NULL)) != NULL)
 807       portnum = ntohs(port->s_port);
 808     else if (!strcmp(service, "http"))
 809       portnum = 80;
 810     else if (!strcmp(service, "https"))
 811       portnum = 443;
 812     else if (!strcmp(service, "ipp") || !strcmp(service, "ipps"))
 813       portnum = 631;
 814     else if (!strcmp(service, "lpd"))
 815       portnum = 515;
 816     else if (!strcmp(service, "socket"))
 817       portnum = 9100;
 818     else
 819     {
 820       httpAddrFreeList(first);
 821
 822       _cupsSetError(IPP_STATUS_ERROR_INTERNAL, _("Unknown service name."), 1);
 823       return (NULL);
 824     }
 825
 826     if (hostname && !_cups_strcasecmp(hostname, "localhost"))
 827     {
 828      /*
 829       * Unfortunately, some users ignore all of the warnings in the
 830       * /etc/hosts file and delete "localhost" from it. If we get here
 831       * then we were unable to resolve the name, so use the IPv6 and/or
 832       * IPv4 loopback interface addresses...
 833       */
 834
 835 #ifdef AF_INET6
 836       if (family != AF_INET)
 837       {
 838        /*
 839         * Add [::1] to the address list...
 840         */
 841
 842         temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 843         if (!temp)
 844         {
 845           _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
 846           httpAddrFreeList(first);
 847           return (NULL);
 848         }
 849
 850         temp->addr.ipv6.sin6_family            = AF_INET6;
 851         temp->addr.ipv6.sin6_port              = htons(portnum);
 852 #  ifdef _WIN32
 853         temp->addr.ipv6.sin6_addr.u.Byte[15]   = 1;
 854 #  else
 855         temp->addr.ipv6.sin6_addr.s6_addr32[3] = htonl(1);
 856 #  endif /* _WIN32 */
 857
 858         if (!first)
 859           first = temp;
 860
 861         addr = temp;
 862       }
 863
 864       if (family != AF_INET6)
 865 #endif /* AF_INET6 */
 866       {
 867        /*
 868         * Add 127.0.0.1 to the address list...
 869         */
 870
 871         temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 872         if (!temp)
 873         {
 874           _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
 875           httpAddrFreeList(first);
 876           return (NULL);
 877         }
 878
 879         temp->addr.ipv4.sin_family      = AF_INET;
 880         temp->addr.ipv4.sin_port        = htons(portnum);
 881         temp->addr.ipv4.sin_addr.s_addr = htonl(0x7f000001);
 882
 883         if (!first)
 884           first = temp;
 885
 886         if (addr)
 887           addr->next = temp;
 888       }
 889     }
 890     else if (!hostname)
 891     {
 892      /*
 893       * Provide one or more passive listening addresses...
 894       */
 895
 896 #ifdef AF_INET6
 897       if (family != AF_INET)
 898       {
 899        /*
 900         * Add [::] to the address list...
 901         */
 902
 903         temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 904         if (!temp)
 905         {
 906           _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
 907           httpAddrFreeList(first);
 908           return (NULL);
 909         }
 910
 911         temp->addr.ipv6.sin6_family = AF_INET6;
 912         temp->addr.ipv6.sin6_port   = htons(portnum);
 913
 914         if (!first)
 915           first = temp;
 916
 917         addr = temp;
 918       }
 919
 920       if (family != AF_INET6)
 921 #endif /* AF_INET6 */
 922       {
 923        /*
 924         * Add 0.0.0.0 to the address list...
 925         */
 926
 927         temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 928         if (!temp)
 929         {
 930           _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
 931           httpAddrFreeList(first);
 932           return (NULL);
 933         }
 934
 935         temp->addr.ipv4.sin_family = AF_INET;
 936         temp->addr.ipv4.sin_port   = htons(portnum);
 937
 938         if (!first)
 939           first = temp;
 940
 941         if (addr)
 942           addr->next = temp;
 943       }
 944     }
 945   }
 946
 947  /*
 948   * Return the address list...
 949   */
 950
 951   return (first);
 952 }