cups/getifaddrs.c

   1 /*
   2  * Network interface functions for CUPS.
   3  *
   4  * Copyright 2007-2010 by Apple Inc.
   5  * Copyright 1997-2006 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  * "LICENSE" which should have been included with this file.  If this
  11  * file is missing or damaged, see the license at "http://www.cups.org/".
  12  */
  13
  14 /*
  15  * Include necessary headers.
  16  */
  17
  18 #include "http-private.h"
  19
  20
  21 #ifndef HAVE_GETIFADDRS
  22 /*
  23  * '_cups_getifaddrs()' - Get a list of network interfaces on the system.
  24  */
  25
  26 int                                     /* O - 0 on success, -1 on error */
  27 _cups_getifaddrs(struct ifaddrs **addrs)/* O - List of interfaces */
  28 {
  29   int                   sock;           /* Socket */
  30   char                  buffer[65536],  /* Buffer for address info */
  31                         *bufptr,        /* Pointer into buffer */
  32                         *bufend;        /* End of buffer */
  33   struct ifconf         conf;           /* Interface configurations */
  34   struct sockaddr       addr;           /* Address data */
  35   struct ifreq          *ifp;           /* Interface data */
  36   int                   ifpsize;        /* Size of interface data */
  37   struct ifaddrs        *temp;          /* Pointer to current interface */
  38   struct ifreq          request;        /* Interface request */
  39
  40
  41  /*
  42   * Start with an empty list...
  43   */
  44
  45   if (addrs == NULL)
  46     return (-1);
  47
  48   *addrs = NULL;
  49
  50  /*
  51   * Create a UDP socket to get the interface data...
  52   */
  53
  54   memset (&addr, 0, sizeof(addr));
  55   if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
  56     return (-1);
  57
  58  /*
  59   * Try to get the list of interfaces...
  60   */
  61
  62   conf.ifc_len = sizeof(buffer);
  63   conf.ifc_buf = buffer;
  64
  65   if (ioctl(sock, SIOCGIFCONF, &conf) < 0)
  66   {
  67    /*
  68     * Couldn't get the list of interfaces...
  69     */
  70
  71     close(sock);
  72     return (-1);
  73   }
  74
  75  /*
  76   * OK, got the list of interfaces, now lets step through the
  77   * buffer to pull them out...
  78   */
  79
  80 #  ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
  81 #    define sockaddr_len(a)     ((a)->sa_len)
  82 #  else
  83 #    define sockaddr_len(a)     (sizeof(struct sockaddr))
  84 #  endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
  85
  86   for (bufptr = buffer, bufend = buffer + conf.ifc_len;
  87        bufptr < bufend;
  88        bufptr += ifpsize)
  89   {
  90    /*
  91     * Get the current interface information...
  92     */
  93
  94     ifp     = (struct ifreq *)bufptr;
  95     ifpsize = sizeof(ifp->ifr_name) + sockaddr_len(&(ifp->ifr_addr));
  96
  97     if (ifpsize < sizeof(struct ifreq))
  98       ifpsize = sizeof(struct ifreq);
  99
 100     memset(&request, 0, sizeof(request));
 101     memcpy(request.ifr_name, ifp->ifr_name, sizeof(ifp->ifr_name));
 102
 103    /*
 104     * Check the status of the interface...
 105     */
 106
 107     if (ioctl(sock, SIOCGIFFLAGS, &request) < 0)
 108       continue;
 109
 110    /*
 111     * Allocate memory for a single interface record...
 112     */
 113
 114     if ((temp = calloc(1, sizeof(struct ifaddrs))) == NULL)
 115     {
 116      /*
 117       * Unable to allocate memory...
 118       */
 119
 120       close(sock);
 121       return (-1);
 122     }
 123
 124    /*
 125     * Add this record to the front of the list and copy the name, flags,
 126     * and network address...
 127     */
 128
 129     temp->ifa_next  = *addrs;
 130     *addrs          = temp;
 131     temp->ifa_name  = strdup(ifp->ifr_name);
 132     temp->ifa_flags = request.ifr_flags;
 133     if ((temp->ifa_addr = calloc(1, sockaddr_len(&(ifp->ifr_addr)))) != NULL)
 134       memcpy(temp->ifa_addr, &(ifp->ifr_addr), sockaddr_len(&(ifp->ifr_addr)));
 135
 136    /*
 137     * Try to get the netmask for the interface...
 138     */
 139
 140     if (!ioctl(sock, SIOCGIFNETMASK, &request))
 141     {
 142      /*
 143       * Got it, make a copy...
 144       */
 145
 146       if ((temp->ifa_netmask = calloc(1, sizeof(request.ifr_netmask))) != NULL)
 147         memcpy(temp->ifa_netmask, &(request.ifr_netmask),
 148                sizeof(request.ifr_netmask));
 149     }
 150
 151    /*
 152     * Then get the broadcast or point-to-point (destination) address,
 153     * if applicable...
 154     */
 155
 156     if (temp->ifa_flags & IFF_BROADCAST)
 157     {
 158      /*
 159       * Have a broadcast address, so get it!
 160       */
 161
 162       if (!ioctl(sock, SIOCGIFBRDADDR, &request))
 163       {
 164        /*
 165         * Got it, make a copy...
 166         */
 167
 168         if ((temp->ifa_broadaddr =
 169                  calloc(1, sizeof(request.ifr_broadaddr))) != NULL)
 170           memcpy(temp->ifa_broadaddr, &(request.ifr_broadaddr),
 171                  sizeof(request.ifr_broadaddr));
 172       }
 173     }
 174     else if (temp->ifa_flags & IFF_POINTOPOINT)
 175     {
 176      /*
 177       * Point-to-point interface; grab the remote address...
 178       */
 179
 180       if (!ioctl(sock, SIOCGIFDSTADDR, &request))
 181       {
 182         temp->ifa_dstaddr = malloc(sizeof(request.ifr_dstaddr));
 183         memcpy(temp->ifa_dstaddr, &(request.ifr_dstaddr),
 184                sizeof(request.ifr_dstaddr));
 185       }
 186     }
 187   }
 188
 189  /*
 190   * OK, we're done with the socket, close it and return 0...
 191   */
 192
 193   close(sock);
 194
 195   return (0);
 196 }
 197
 198
 199 /*
 200  * '_cups_freeifaddrs()' - Free an interface list...
 201  */
 202
 203 void
 204 _cups_freeifaddrs(struct ifaddrs *addrs)/* I - Interface list to free */
 205 {
 206   struct ifaddrs        *next;          /* Next interface in list */
 207
 208
 209   while (addrs != NULL)
 210   {
 211    /*
 212     * Make a copy of the next interface pointer...
 213     */
 214
 215     next = addrs->ifa_next;
 216
 217    /*
 218     * Free data values as needed...
 219     */
 220
 221     if (addrs->ifa_name)
 222     {
 223       free(addrs->ifa_name);
 224       addrs->ifa_name = NULL;
 225     }
 226
 227     if (addrs->ifa_addr)
 228     {
 229       free(addrs->ifa_addr);
 230       addrs->ifa_addr = NULL;
 231     }
 232
 233     if (addrs->ifa_netmask)
 234     {
 235       free(addrs->ifa_netmask);
 236       addrs->ifa_netmask = NULL;
 237     }
 238
 239     if (addrs->ifa_dstaddr)
 240     {
 241       free(addrs->ifa_dstaddr);
 242       addrs->ifa_dstaddr = NULL;
 243     }
 244
 245    /*
 246     * Free this node and continue to the next...
 247     */
 248
 249     free(addrs);
 250
 251     addrs = next;
 252   }
 253 }
 254 #endif /* !HAVE_GETIFADDRS */