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  * Licensed under Apache License v2.0.  See the file "LICENSE" for more
   8  * information.
   9  */
  10
  11 /*
  12  * Include necessary headers...
  13  */
  14
  15 #include "cups-private.h"
  16 #ifdef HAVE_RESOLV_H
  17 #  include <resolv.h>
  18 #endif /* HAVE_RESOLV_H */
  19 #ifdef HAVE_POLL
  20 #  include <poll.h>
  21 #endif /* HAVE_POLL */
  22 #ifndef _WIN32
  23 #  include <fcntl.h>
  24 #endif /* _WIN32 */
  25
  26
  27 /*
  28  * 'httpAddrConnect()' - Connect to any of the addresses in the list.
  29  *
  30  * @since CUPS 1.2/macOS 10.5@ @exclude all@
  31  */
  32
  33 http_addrlist_t *                       /* O - Connected address or NULL on failure */
  34 httpAddrConnect(
  35     http_addrlist_t *addrlist,          /* I - List of potential addresses */
  36     int             *sock)              /* O - Socket */
  37 {
  38   DEBUG_printf(("httpAddrConnect(addrlist=%p, sock=%p)", (void *)addrlist, (void *)sock));
  39
  40   return (httpAddrConnect2(addrlist, sock, 30000, NULL));
  41 }
  42
  43
  44 /*
  45  * 'httpAddrConnect2()' - Connect to any of the addresses in the list with a
  46  *                        timeout and optional cancel.
  47  *
  48  * @since CUPS 1.7/macOS 10.9@
  49  */
  50
  51 http_addrlist_t *                       /* O - Connected address or NULL on failure */
  52 httpAddrConnect2(
  53     http_addrlist_t *addrlist,          /* I - List of potential addresses */
  54     int             *sock,              /* O - Socket */
  55     int             msec,               /* I - Timeout in milliseconds */
  56     int             *cancel)            /* I - Pointer to "cancel" variable */
  57 {
  58   int                   val;            /* Socket option value */
  59 #ifndef _WIN32
  60   int                   i, j,           /* Looping vars */
  61                         flags,          /* Socket flags */
  62                         result;         /* Result from select() or poll() */
  63 #endif /* !_WIN32 */
  64   int                   remaining;      /* Remaining timeout */
  65   int                   nfds,           /* Number of file descriptors */
  66                         fds[100];       /* Socket file descriptors */
  67   http_addrlist_t       *addrs[100];    /* Addresses */
  68 #ifndef HAVE_POLL
  69   int                   max_fd = -1;    /* Highest file descriptor */
  70 #endif /* !HAVE_POLL */
  71 #ifdef O_NONBLOCK
  72 #  ifdef HAVE_POLL
  73   struct pollfd         pfds[100];      /* Polled file descriptors */
  74 #  else
  75   fd_set                input_set,      /* select() input set */
  76                         output_set,     /* select() output set */
  77                         error_set;      /* select() error set */
  78   struct timeval        timeout;        /* Timeout */
  79 #  endif /* HAVE_POLL */
  80 #endif /* O_NONBLOCK */
  81 #ifdef DEBUG
  82 #  ifndef _WIN32
  83   socklen_t             len;            /* Length of value */
  84   http_addr_t           peer;           /* Peer address */
  85 #  endif /* !_WIN32 */
  86   char                  temp[256];      /* Temporary address string */
  87 #endif /* DEBUG */
  88
  89
  90   DEBUG_printf(("httpAddrConnect2(addrlist=%p, sock=%p, msec=%d, cancel=%p)", (void *)addrlist, (void *)sock, msec, (void *)cancel));
  91
  92   if (!sock)
  93   {
  94     errno = EINVAL;
  95     _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
  96     return (NULL);
  97   }
  98
  99   if (cancel && *cancel)
 100     return (NULL);
 101
 102   if (msec <= 0)
 103     msec = INT_MAX;
 104
 105  /*
 106   * Loop through each address until we connect or run out of addresses...
 107   */
 108
 109   nfds      = 0;
 110   remaining = msec;
 111
 112   while (remaining > 0)
 113   {
 114     if (cancel && *cancel)
 115     {
 116       while (nfds > 0)
 117       {
 118         nfds --;
 119         httpAddrClose(NULL, fds[nfds]);
 120       }
 121
 122       return (NULL);
 123     }
 124
 125     if (addrlist && nfds < (int)(sizeof(fds) / sizeof(fds[0])))
 126     {
 127      /*
 128       * Create the socket...
 129       */
 130
 131       DEBUG_printf(("2httpAddrConnect2: Trying %s:%d...", httpAddrString(&(addrlist->addr), temp, sizeof(temp)), httpAddrPort(&(addrlist->addr))));
 132
 133       if ((fds[nfds] = (int)socket(httpAddrFamily(&(addrlist->addr)), SOCK_STREAM, 0)) < 0)
 134       {
 135        /*
 136         * Don't abort yet, as this could just be an issue with the local
 137         * system not being configured with IPv4/IPv6/domain socket enabled.
 138         *
 139         * Just skip this address...
 140         */
 141
 142         addrlist = addrlist->next;
 143         continue;
 144       }
 145
 146      /*
 147       * Set options...
 148       */
 149
 150       val = 1;
 151       setsockopt(fds[nfds], SOL_SOCKET, SO_REUSEADDR, CUPS_SOCAST &val, sizeof(val));
 152
 153 #ifdef SO_REUSEPORT
 154       val = 1;
 155       setsockopt(fds[nfds], SOL_SOCKET, SO_REUSEPORT, CUPS_SOCAST &val, sizeof(val));
 156 #endif /* SO_REUSEPORT */
 157
 158 #ifdef SO_NOSIGPIPE
 159       val = 1;
 160       setsockopt(fds[nfds], SOL_SOCKET, SO_NOSIGPIPE, CUPS_SOCAST &val, sizeof(val));
 161 #endif /* SO_NOSIGPIPE */
 162
 163      /*
 164       * Using TCP_NODELAY improves responsiveness, especially on systems
 165       * with a slow loopback interface...
 166       */
 167
 168       val = 1;
 169       setsockopt(fds[nfds], IPPROTO_TCP, TCP_NODELAY, CUPS_SOCAST &val, sizeof(val));
 170
 171 #ifdef FD_CLOEXEC
 172      /*
 173       * Close this socket when starting another process...
 174       */
 175
 176       fcntl(fds[nfds], 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(fds[nfds], F_GETFL, 0);
 187       fcntl(fds[nfds], F_SETFL, flags | O_NONBLOCK);
 188 #endif /* O_NONBLOCK */
 189
 190      /*
 191       * Then connect...
 192       */
 193
 194       if (!connect(fds[nfds], &(addrlist->addr.addr), (socklen_t)httpAddrLength(&(addrlist->addr))))
 195       {
 196         DEBUG_printf(("1httpAddrConnect2: Connected to %s:%d...", httpAddrString(&(addrlist->addr), temp, sizeof(temp)), httpAddrPort(&(addrlist->addr))));
 197
 198 #ifdef O_NONBLOCK
 199         fcntl(fds[nfds], F_SETFL, flags);
 200 #endif /* O_NONBLOCK */
 201
 202         *sock = fds[nfds];
 203
 204         while (nfds > 0)
 205         {
 206           nfds --;
 207           httpAddrClose(NULL, fds[nfds]);
 208         }
 209
 210         return (addrlist);
 211       }
 212
 213 #ifdef _WIN32
 214       if (WSAGetLastError() != WSAEINPROGRESS && WSAGetLastError() != WSAEWOULDBLOCK)
 215 #else
 216       if (errno != EINPROGRESS && errno != EWOULDBLOCK)
 217 #endif /* _WIN32 */
 218       {
 219         DEBUG_printf(("1httpAddrConnect2: Unable to connect to %s:%d: %s", httpAddrString(&(addrlist->addr), temp, sizeof(temp)), httpAddrPort(&(addrlist->addr)), strerror(errno)));
 220         httpAddrClose(NULL, fds[nfds]);
 221         addrlist = addrlist->next;
 222         continue;
 223       }
 224
 225 #ifndef _WIN32
 226       fcntl(fds[nfds], F_SETFL, flags);
 227 #endif /* !_WIN32 */
 228
 229 #ifndef HAVE_POLL
 230       if (fds[nfds] > max_fd)
 231         max_fd = fds[nfds];
 232 #endif /* !HAVE_POLL */
 233
 234       addrs[nfds] = addrlist;
 235       nfds ++;
 236       addrlist = addrlist->next;
 237     }
 238
 239     if (!addrlist && nfds == 0)
 240       break;
 241
 242    /*
 243     * See if we can connect to any of the addresses so far...
 244     */
 245
 246 #ifdef O_NONBLOCK
 247     DEBUG_puts("1httpAddrConnect2: Finishing async connect()");
 248
 249     do
 250     {
 251       if (cancel && *cancel)
 252       {
 253        /*
 254         * Close this socket and return...
 255         */
 256
 257         DEBUG_puts("1httpAddrConnect2: Canceled connect()");
 258
 259         while (nfds > 0)
 260         {
 261           nfds --;
 262           httpAddrClose(NULL, fds[nfds]);
 263         }
 264
 265         *sock = -1;
 266
 267         return (NULL);
 268       }
 269
 270 #  ifdef HAVE_POLL
 271       for (i = 0; i < nfds; i ++)
 272       {
 273         pfds[i].fd     = fds[i];
 274         pfds[i].events = POLLIN | POLLOUT;
 275       }
 276
 277       result = poll(pfds, (nfds_t)nfds, addrlist ? 100 : remaining > 250 ? 250 : remaining);
 278
 279       DEBUG_printf(("1httpAddrConnect2: poll() returned %d (%d)", result, errno));
 280
 281 #  else
 282       FD_ZERO(&input_set);
 283       for (i = 0; i < nfds; i ++)
 284         FD_SET(fds[i], &input_set);
 285       output_set = input_set;
 286       error_set  = input_set;
 287
 288       timeout.tv_sec  = 0;
 289       timeout.tv_usec = (addrlist ? 100 : remaining > 250 ? 250 : remaining) * 1000;
 290
 291       result = select(max_fd + 1, &input_set, &output_set, &error_set, &timeout);
 292
 293       DEBUG_printf(("1httpAddrConnect2: select() returned %d (%d)", result, errno));
 294 #  endif /* HAVE_POLL */
 295     }
 296 #  ifdef _WIN32
 297     while (result < 0 && (WSAGetLastError() == WSAEINTR || WSAGetLastError() == WSAEWOULDBLOCK));
 298 #  else
 299     while (result < 0 && (errno == EINTR || errno == EAGAIN));
 300 #  endif /* _WIN32 */
 301
 302     if (result > 0)
 303     {
 304       http_addrlist_t *connaddr = NULL; /* Connected address, if any */
 305
 306       for (i = 0; i < nfds; i ++)
 307       {
 308 #  ifdef HAVE_POLL
 309         DEBUG_printf(("pfds[%d].revents=%x\n", i, pfds[i].revents));
 310         if (pfds[i].revents && !(pfds[i].revents & (POLLERR | POLLHUP)))
 311 #  else
 312         if (FD_ISSET(fds[i], &input_set) && !FD_ISSET(fds[i], &error_set))
 313 #  endif /* HAVE_POLL */
 314         {
 315           *sock    = fds[i];
 316           connaddr = addrs[i];
 317
 318 #  ifdef DEBUG
 319           len   = sizeof(peer);
 320           if (!getpeername(fds[i], (struct sockaddr *)&peer, &len))
 321             DEBUG_printf(("1httpAddrConnect2: Connected to %s:%d...", httpAddrString(&peer, temp, sizeof(temp)), httpAddrPort(&peer)));
 322 #  endif /* DEBUG */
 323
 324           break;
 325         }
 326 #  ifdef HAVE_POLL
 327         else if (pfds[i].revents & (POLLERR | POLLHUP))
 328 #  else
 329         else if (FD_ISSET(fds[i], &error_set))
 330 #  endif /* HAVE_POLL */
 331         {
 332          /*
 333           * Error on socket, remove from the "pool"...
 334           */
 335
 336           httpAddrClose(NULL, fds[i]);
 337           nfds --;
 338           if (i < nfds)
 339           {
 340             memmove(fds + i, fds + i + 1, (size_t)(nfds - i) * (sizeof(fds[0])));
 341             memmove(addrs + i, addrs + i + 1, (size_t)(nfds - i) * (sizeof(addrs[0])));
 342           }
 343           i --;
 344         }
 345       }
 346
 347       if (connaddr)
 348       {
 349        /*
 350         * Connected on one address, close all of the other sockets we have so
 351         * far and return...
 352         */
 353
 354         for (j = 0; j < i; j ++)
 355           httpAddrClose(NULL, fds[j]);
 356
 357         for (j ++; j < nfds; j ++)
 358           httpAddrClose(NULL, fds[j]);
 359
 360         return (connaddr);
 361       }
 362     }
 363 #endif /* O_NONBLOCK */
 364
 365     if (addrlist)
 366       remaining -= 100;
 367     else
 368       remaining -= 250;
 369   }
 370
 371   while (nfds > 0)
 372   {
 373     nfds --;
 374     httpAddrClose(NULL, fds[nfds]);
 375   }
 376
 377 #ifdef _WIN32
 378   _cupsSetError(IPP_STATUS_ERROR_SERVICE_UNAVAILABLE, "Connection failed", 0);
 379 #else
 380   _cupsSetError(IPP_STATUS_ERROR_SERVICE_UNAVAILABLE, strerror(errno), 0);
 381 #endif /* _WIN32 */
 382
 383   return (NULL);
 384 }
 385
 386
 387 /*
 388  * 'httpAddrCopyList()' - Copy an address list.
 389  *
 390  * @since CUPS 1.7/macOS 10.9@
 391  */
 392
 393 http_addrlist_t *                       /* O - New address list or @code NULL@ on error */
 394 httpAddrCopyList(
 395     http_addrlist_t *src)               /* I - Source address list */
 396 {
 397   http_addrlist_t       *dst = NULL,    /* First list entry */
 398                         *prev = NULL,   /* Previous list entry */
 399                         *current = NULL;/* Current list entry */
 400
 401
 402   while (src)
 403   {
 404     if ((current = malloc(sizeof(http_addrlist_t))) == NULL)
 405     {
 406       current = dst;
 407
 408       while (current)
 409       {
 410         prev    = current;
 411         current = current->next;
 412
 413         free(prev);
 414       }
 415
 416       return (NULL);
 417     }
 418
 419     memcpy(current, src, sizeof(http_addrlist_t));
 420
 421     current->next = NULL;
 422
 423     if (prev)
 424       prev->next = current;
 425     else
 426       dst = current;
 427
 428     prev = current;
 429     src  = src->next;
 430   }
 431
 432   return (dst);
 433 }
 434
 435
 436 /*
 437  * 'httpAddrFreeList()' - Free an address list.
 438  *
 439  * @since CUPS 1.2/macOS 10.5@
 440  */
 441
 442 void
 443 httpAddrFreeList(
 444     http_addrlist_t *addrlist)          /* I - Address list to free */
 445 {
 446   http_addrlist_t       *next;          /* Next address in list */
 447
 448
 449  /*
 450   * Free each address in the list...
 451   */
 452
 453   while (addrlist)
 454   {
 455     next = addrlist->next;
 456
 457     free(addrlist);
 458
 459     addrlist = next;
 460   }
 461 }
 462
 463
 464 /*
 465  * 'httpAddrGetList()' - Get a list of addresses for a hostname.
 466  *
 467  * @since CUPS 1.2/macOS 10.5@
 468  */
 469
 470 http_addrlist_t *                       /* O - List of addresses or NULL */
 471 httpAddrGetList(const char *hostname,   /* I - Hostname, IP address, or NULL for passive listen address */
 472                 int        family,      /* I - Address family or AF_UNSPEC */
 473                 const char *service)    /* I - Service name or port number */
 474 {
 475   http_addrlist_t       *first,         /* First address in list */
 476                         *addr,          /* Current address in list */
 477                         *temp;          /* New address */
 478   _cups_globals_t       *cg = _cupsGlobals();
 479                                         /* Global data */
 480
 481
 482 #ifdef DEBUG
 483   _cups_debug_printf("httpAddrGetList(hostname=\"%s\", family=AF_%s, "
 484                      "service=\"%s\")\n",
 485                      hostname ? hostname : "(nil)",
 486                      family == AF_UNSPEC ? "UNSPEC" :
 487 #  ifdef AF_LOCAL
 488                          family == AF_LOCAL ? "LOCAL" :
 489 #  endif /* AF_LOCAL */
 490 #  ifdef AF_INET6
 491                          family == AF_INET6 ? "INET6" :
 492 #  endif /* AF_INET6 */
 493                          family == AF_INET ? "INET" : "???", service);
 494 #endif /* DEBUG */
 495
 496 #ifdef HAVE_RES_INIT
 497  /*
 498   * STR #2920: Initialize resolver after failure in cups-polld
 499   *
 500   * If the previous lookup failed, re-initialize the resolver to prevent
 501   * temporary network errors from persisting.  This *should* be handled by
 502   * the resolver libraries, but apparently the glibc folks do not agree.
 503   *
 504   * We set a flag at the end of this function if we encounter an error that
 505   * requires reinitialization of the resolver functions.  We then call
 506   * res_init() if the flag is set on the next call here or in httpAddrLookup().
 507   */
 508
 509   if (cg->need_res_init)
 510   {
 511     res_init();
 512
 513     cg->need_res_init = 0;
 514   }
 515 #endif /* HAVE_RES_INIT */
 516
 517  /*
 518   * Lookup the address the best way we can...
 519   */
 520
 521   first = addr = NULL;
 522
 523 #ifdef AF_LOCAL
 524   if (hostname && hostname[0] == '/')
 525   {
 526    /*
 527     * Domain socket address...
 528     */
 529
 530     if ((first = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t))) != NULL)
 531     {
 532       addr = first;
 533       first->addr.un.sun_family = AF_LOCAL;
 534       strlcpy(first->addr.un.sun_path, hostname, sizeof(first->addr.un.sun_path));
 535     }
 536   }
 537   else
 538 #endif /* AF_LOCAL */
 539   if (!hostname || _cups_strcasecmp(hostname, "localhost"))
 540   {
 541 #ifdef HAVE_GETADDRINFO
 542     struct addrinfo     hints,          /* Address lookup hints */
 543                         *results,       /* Address lookup results */
 544                         *current;       /* Current result */
 545     char                ipv6[64],       /* IPv6 address */
 546                         *ipv6zone;      /* Pointer to zone separator */
 547     int                 ipv6len;        /* Length of IPv6 address */
 548     int                 error;          /* getaddrinfo() error */
 549
 550
 551    /*
 552     * Lookup the address as needed...
 553     */
 554
 555     memset(&hints, 0, sizeof(hints));
 556     hints.ai_family   = family;
 557     hints.ai_flags    = hostname ? 0 : AI_PASSIVE;
 558     hints.ai_socktype = SOCK_STREAM;
 559
 560     if (hostname && *hostname == '[')
 561     {
 562      /*
 563       * Remove brackets from numeric IPv6 address...
 564       */
 565
 566       if (!strncmp(hostname, "[v1.", 4))
 567       {
 568        /*
 569         * Copy the newer address format which supports link-local addresses...
 570         */
 571
 572         strlcpy(ipv6, hostname + 4, sizeof(ipv6));
 573         if ((ipv6len = (int)strlen(ipv6) - 1) >= 0 && ipv6[ipv6len] == ']')
 574         {
 575           ipv6[ipv6len] = '\0';
 576           hostname      = ipv6;
 577
 578          /*
 579           * Convert "+zone" in address to "%zone"...
 580           */
 581
 582           if ((ipv6zone = strrchr(ipv6, '+')) != NULL)
 583             *ipv6zone = '%';
 584         }
 585       }
 586       else
 587       {
 588        /*
 589         * Copy the regular non-link-local IPv6 address...
 590         */
 591
 592         strlcpy(ipv6, hostname + 1, sizeof(ipv6));
 593         if ((ipv6len = (int)strlen(ipv6) - 1) >= 0 && ipv6[ipv6len] == ']')
 594         {
 595           ipv6[ipv6len] = '\0';
 596           hostname      = ipv6;
 597         }
 598       }
 599     }
 600
 601     if ((error = getaddrinfo(hostname, service, &hints, &results)) == 0)
 602     {
 603      /*
 604       * Copy the results to our own address list structure...
 605       */
 606
 607       for (current = results; current; current = current->ai_next)
 608         if (current->ai_family == AF_INET || current->ai_family == AF_INET6)
 609         {
 610          /*
 611           * Copy the address over...
 612           */
 613
 614           temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 615           if (!temp)
 616           {
 617             httpAddrFreeList(first);
 618             freeaddrinfo(results);
 619             _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
 620             return (NULL);
 621           }
 622
 623           if (current->ai_family == AF_INET6)
 624             memcpy(&(temp->addr.ipv6), current->ai_addr,
 625                    sizeof(temp->addr.ipv6));
 626           else
 627             memcpy(&(temp->addr.ipv4), current->ai_addr,
 628                    sizeof(temp->addr.ipv4));
 629
 630          /*
 631           * Append the address to the list...
 632           */
 633
 634           if (!first)
 635             first = temp;
 636
 637           if (addr)
 638             addr->next = temp;
 639
 640           addr = temp;
 641         }
 642
 643      /*
 644       * Free the results from getaddrinfo()...
 645       */
 646
 647       freeaddrinfo(results);
 648     }
 649     else
 650     {
 651       if (error == EAI_FAIL)
 652         cg->need_res_init = 1;
 653
 654 #  ifdef _WIN32 /* Really, Microsoft?!? */
 655       _cupsSetError(IPP_STATUS_ERROR_INTERNAL, gai_strerrorA(error), 0);
 656 #  else
 657       _cupsSetError(IPP_STATUS_ERROR_INTERNAL, gai_strerror(error), 0);
 658 #  endif /* _WIN32 */
 659     }
 660
 661 #else
 662     if (hostname)
 663     {
 664       int               i;              /* Looping vars */
 665       unsigned          ip[4];          /* IPv4 address components */
 666       const char        *ptr;           /* Pointer into hostname */
 667       struct hostent    *host;          /* Result of lookup */
 668       struct servent    *port;          /* Port number for service */
 669       int               portnum;        /* Port number */
 670
 671
 672      /*
 673       * Lookup the service...
 674       */
 675
 676       if (!service)
 677         portnum = 0;
 678       else if (isdigit(*service & 255))
 679         portnum = atoi(service);
 680       else if ((port = getservbyname(service, NULL)) != NULL)
 681         portnum = ntohs(port->s_port);
 682       else if (!strcmp(service, "http"))
 683         portnum = 80;
 684       else if (!strcmp(service, "https"))
 685         portnum = 443;
 686       else if (!strcmp(service, "ipp") || !strcmp(service, "ipps"))
 687         portnum = 631;
 688       else if (!strcmp(service, "lpd"))
 689         portnum = 515;
 690       else if (!strcmp(service, "socket"))
 691         portnum = 9100;
 692       else
 693         return (NULL);
 694
 695      /*
 696       * This code is needed because some operating systems have a
 697       * buggy implementation of gethostbyname() that does not support
 698       * IPv4 addresses.  If the hostname string is an IPv4 address, then
 699       * sscanf() is used to extract the IPv4 components.  We then pack
 700       * the components into an IPv4 address manually, since the
 701       * inet_aton() function is deprecated.  We use the htonl() macro
 702       * to get the right byte order for the address.
 703       */
 704
 705       for (ptr = hostname; isdigit(*ptr & 255) || *ptr == '.'; ptr ++);
 706
 707       if (!*ptr)
 708       {
 709        /*
 710         * We have an IPv4 address; break it up and create an IPv4 address...
 711         */
 712
 713         if (sscanf(hostname, "%u.%u.%u.%u", ip, ip + 1, ip + 2, ip + 3) == 4 &&
 714             ip[0] <= 255 && ip[1] <= 255 && ip[2] <= 255 && ip[3] <= 255)
 715         {
 716           first = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 717           if (!first)
 718             return (NULL);
 719
 720           first->addr.ipv4.sin_family = AF_INET;
 721           first->addr.ipv4.sin_addr.s_addr = htonl((((((((unsigned)ip[0] << 8) |
 722                                                        (unsigned)ip[1]) << 8) |
 723                                                      (unsigned)ip[2]) << 8) |
 724                                                    (unsigned)ip[3]));
 725           first->addr.ipv4.sin_port = htons(portnum);
 726         }
 727       }
 728       else if ((host = gethostbyname(hostname)) != NULL &&
 729 #  ifdef AF_INET6
 730                (host->h_addrtype == AF_INET || host->h_addrtype == AF_INET6))
 731 #  else
 732                host->h_addrtype == AF_INET)
 733 #  endif /* AF_INET6 */
 734       {
 735         for (i = 0; host->h_addr_list[i]; i ++)
 736         {
 737          /*
 738           * Copy the address over...
 739           */
 740
 741           temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 742           if (!temp)
 743           {
 744             httpAddrFreeList(first);
 745             return (NULL);
 746           }
 747
 748 #  ifdef AF_INET6
 749           if (host->h_addrtype == AF_INET6)
 750           {
 751             temp->addr.ipv6.sin6_family = AF_INET6;
 752             memcpy(&(temp->addr.ipv6.sin6_addr), host->h_addr_list[i],
 753                    sizeof(temp->addr.ipv6));
 754             temp->addr.ipv6.sin6_port = htons(portnum);
 755           }
 756           else
 757 #  endif /* AF_INET6 */
 758           {
 759             temp->addr.ipv4.sin_family = AF_INET;
 760             memcpy(&(temp->addr.ipv4.sin_addr), host->h_addr_list[i],
 761                    sizeof(temp->addr.ipv4));
 762             temp->addr.ipv4.sin_port = htons(portnum);
 763           }
 764
 765          /*
 766           * Append the address to the list...
 767           */
 768
 769           if (!first)
 770             first = temp;
 771
 772           if (addr)
 773             addr->next = temp;
 774
 775           addr = temp;
 776         }
 777       }
 778       else
 779       {
 780         if (h_errno == NO_RECOVERY)
 781           cg->need_res_init = 1;
 782
 783         _cupsSetError(IPP_STATUS_ERROR_INTERNAL, hstrerror(h_errno), 0);
 784       }
 785     }
 786 #endif /* HAVE_GETADDRINFO */
 787   }
 788
 789  /*
 790   * Detect some common errors and handle them sanely...
 791   */
 792
 793   if (!addr && (!hostname || !_cups_strcasecmp(hostname, "localhost")))
 794   {
 795     struct servent      *port;          /* Port number for service */
 796     int                 portnum;        /* Port number */
 797
 798
 799    /*
 800     * Lookup the service...
 801     */
 802
 803     if (!service)
 804       portnum = 0;
 805     else if (isdigit(*service & 255))
 806       portnum = atoi(service);
 807     else if ((port = getservbyname(service, NULL)) != NULL)
 808       portnum = ntohs(port->s_port);
 809     else if (!strcmp(service, "http"))
 810       portnum = 80;
 811     else if (!strcmp(service, "https"))
 812       portnum = 443;
 813     else if (!strcmp(service, "ipp") || !strcmp(service, "ipps"))
 814       portnum = 631;
 815     else if (!strcmp(service, "lpd"))
 816       portnum = 515;
 817     else if (!strcmp(service, "socket"))
 818       portnum = 9100;
 819     else
 820     {
 821       httpAddrFreeList(first);
 822
 823       _cupsSetError(IPP_STATUS_ERROR_INTERNAL, _("Unknown service name."), 1);
 824       return (NULL);
 825     }
 826
 827     if (hostname && !_cups_strcasecmp(hostname, "localhost"))
 828     {
 829      /*
 830       * Unfortunately, some users ignore all of the warnings in the
 831       * /etc/hosts file and delete "localhost" from it. If we get here
 832       * then we were unable to resolve the name, so use the IPv6 and/or
 833       * IPv4 loopback interface addresses...
 834       */
 835
 836 #ifdef AF_INET6
 837       if (family != AF_INET)
 838       {
 839        /*
 840         * Add [::1] to the address list...
 841         */
 842
 843         temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 844         if (!temp)
 845         {
 846           _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
 847           httpAddrFreeList(first);
 848           return (NULL);
 849         }
 850
 851         temp->addr.ipv6.sin6_family            = AF_INET6;
 852         temp->addr.ipv6.sin6_port              = htons(portnum);
 853 #  ifdef _WIN32
 854         temp->addr.ipv6.sin6_addr.u.Byte[15]   = 1;
 855 #  else
 856         temp->addr.ipv6.sin6_addr.s6_addr32[3] = htonl(1);
 857 #  endif /* _WIN32 */
 858
 859         if (!first)
 860           first = temp;
 861
 862         addr = temp;
 863       }
 864
 865       if (family != AF_INET6)
 866 #endif /* AF_INET6 */
 867       {
 868        /*
 869         * Add 127.0.0.1 to the address list...
 870         */
 871
 872         temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 873         if (!temp)
 874         {
 875           _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
 876           httpAddrFreeList(first);
 877           return (NULL);
 878         }
 879
 880         temp->addr.ipv4.sin_family      = AF_INET;
 881         temp->addr.ipv4.sin_port        = htons(portnum);
 882         temp->addr.ipv4.sin_addr.s_addr = htonl(0x7f000001);
 883
 884         if (!first)
 885           first = temp;
 886
 887         if (addr)
 888           addr->next = temp;
 889       }
 890     }
 891     else if (!hostname)
 892     {
 893      /*
 894       * Provide one or more passive listening addresses...
 895       */
 896
 897 #ifdef AF_INET6
 898       if (family != AF_INET)
 899       {
 900        /*
 901         * Add [::] to the address list...
 902         */
 903
 904         temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 905         if (!temp)
 906         {
 907           _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
 908           httpAddrFreeList(first);
 909           return (NULL);
 910         }
 911
 912         temp->addr.ipv6.sin6_family = AF_INET6;
 913         temp->addr.ipv6.sin6_port   = htons(portnum);
 914
 915         if (!first)
 916           first = temp;
 917
 918         addr = temp;
 919       }
 920
 921       if (family != AF_INET6)
 922 #endif /* AF_INET6 */
 923       {
 924        /*
 925         * Add 0.0.0.0 to the address list...
 926         */
 927
 928         temp = (http_addrlist_t *)calloc(1, sizeof(http_addrlist_t));
 929         if (!temp)
 930         {
 931           _cupsSetError(IPP_STATUS_ERROR_INTERNAL, strerror(errno), 0);
 932           httpAddrFreeList(first);
 933           return (NULL);
 934         }
 935
 936         temp->addr.ipv4.sin_family = AF_INET;
 937         temp->addr.ipv4.sin_port   = htons(portnum);
 938
 939         if (!first)
 940           first = temp;
 941
 942         if (addr)
 943           addr->next = temp;
 944       }
 945     }
 946   }
 947
 948  /*
 949   * Return the address list...
 950   */
 951
 952   return (first);
 953 }