cups/getifaddrs.c

   1 /*
   2  * "$Id$"
   3  *
   4  *   Network interface functions for CUPS.
   5  *
   6  *   Copyright 2007-2010 by Apple Inc.
   7  *   Copyright 1997-2006 by Easy Software Products, all rights reserved.
   8  *
   9  *   These coded instructions, statements, and computer programs are the
  10  *   property of Apple Inc. and are protected by Federal copyright
  11  *   law.  Distribution and use rights are outlined in the file "LICENSE.txt"
  12  *   "LICENSE" which should have been included with this file.  If this
  13  *   file is missing or damaged, see the license at "http://www.cups.org/".
  14  *
  15  * Contents:
  16  *
  17  *   _cups_getifaddrs()  - Get a list of network interfaces on the system.
  18  *   _cups_freeifaddrs() - Free an interface list...
  19  */
  20
  21 /*
  22  * Include necessary headers.
  23  */
  24
  25 #include "http-private.h"
  26
  27
  28 #ifndef HAVE_GETIFADDRS
  29 /*
  30  * '_cups_getifaddrs()' - Get a list of network interfaces on the system.
  31  */
  32
  33 int                                     /* O - 0 on success, -1 on error */
  34 _cups_getifaddrs(struct ifaddrs **addrs)/* O - List of interfaces */
  35 {
  36   int                   sock;           /* Socket */
  37   char                  buffer[65536],  /* Buffer for address info */
  38                         *bufptr,        /* Pointer into buffer */
  39                         *bufend;        /* End of buffer */
  40   struct ifconf         conf;           /* Interface configurations */
  41   struct sockaddr       addr;           /* Address data */
  42   struct ifreq          *ifp;           /* Interface data */
  43   int                   ifpsize;        /* Size of interface data */
  44   struct ifaddrs        *temp;          /* Pointer to current interface */
  45   struct ifreq          request;        /* Interface request */
  46
  47
  48  /*
  49   * Start with an empty list...
  50   */
  51
  52   if (addrs == NULL)
  53     return (-1);
  54
  55   *addrs = NULL;
  56
  57  /*
  58   * Create a UDP socket to get the interface data...
  59   */
  60
  61   memset (&addr, 0, sizeof(addr));
  62   if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
  63     return (-1);
  64
  65  /*
  66   * Try to get the list of interfaces...
  67   */
  68
  69   conf.ifc_len = sizeof(buffer);
  70   conf.ifc_buf = buffer;
  71
  72   if (ioctl(sock, SIOCGIFCONF, &conf) < 0)
  73   {
  74    /*
  75     * Couldn't get the list of interfaces...
  76     */
  77
  78     close(sock);
  79     return (-1);
  80   }
  81
  82  /*
  83   * OK, got the list of interfaces, now lets step through the
  84   * buffer to pull them out...
  85   */
  86
  87 #  ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
  88 #    define sockaddr_len(a)     ((a)->sa_len)
  89 #  else
  90 #    define sockaddr_len(a)     (sizeof(struct sockaddr))
  91 #  endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
  92
  93   for (bufptr = buffer, bufend = buffer + conf.ifc_len;
  94        bufptr < bufend;
  95        bufptr += ifpsize)
  96   {
  97    /*
  98     * Get the current interface information...
  99     */
 100
 101     ifp     = (struct ifreq *)bufptr;
 102     ifpsize = sizeof(ifp->ifr_name) + sockaddr_len(&(ifp->ifr_addr));
 103
 104     if (ifpsize < sizeof(struct ifreq))
 105       ifpsize = sizeof(struct ifreq);
 106
 107     memset(&request, 0, sizeof(request));
 108     memcpy(request.ifr_name, ifp->ifr_name, sizeof(ifp->ifr_name));
 109
 110    /*
 111     * Check the status of the interface...
 112     */
 113
 114     if (ioctl(sock, SIOCGIFFLAGS, &request) < 0)
 115       continue;
 116
 117    /*
 118     * Allocate memory for a single interface record...
 119     */
 120
 121     if ((temp = calloc(1, sizeof(struct ifaddrs))) == NULL)
 122     {
 123      /*
 124       * Unable to allocate memory...
 125       */
 126
 127       close(sock);
 128       return (-1);
 129     }
 130
 131    /*
 132     * Add this record to the front of the list and copy the name, flags,
 133     * and network address...
 134     */
 135
 136     temp->ifa_next  = *addrs;
 137     *addrs          = temp;
 138     temp->ifa_name  = strdup(ifp->ifr_name);
 139     temp->ifa_flags = request.ifr_flags;
 140     if ((temp->ifa_addr = calloc(1, sockaddr_len(&(ifp->ifr_addr)))) != NULL)
 141       memcpy(temp->ifa_addr, &(ifp->ifr_addr), sockaddr_len(&(ifp->ifr_addr)));
 142
 143    /*
 144     * Try to get the netmask for the interface...
 145     */
 146
 147     if (!ioctl(sock, SIOCGIFNETMASK, &request))
 148     {
 149      /*
 150       * Got it, make a copy...
 151       */
 152
 153       if ((temp->ifa_netmask = calloc(1, sizeof(request.ifr_netmask))) != NULL)
 154         memcpy(temp->ifa_netmask, &(request.ifr_netmask),
 155                sizeof(request.ifr_netmask));
 156     }
 157
 158    /*
 159     * Then get the broadcast or point-to-point (destination) address,
 160     * if applicable...
 161     */
 162
 163     if (temp->ifa_flags & IFF_BROADCAST)
 164     {
 165      /*
 166       * Have a broadcast address, so get it!
 167       */
 168
 169       if (!ioctl(sock, SIOCGIFBRDADDR, &request))
 170       {
 171        /*
 172         * Got it, make a copy...
 173         */
 174
 175         if ((temp->ifa_broadaddr =
 176                  calloc(1, sizeof(request.ifr_broadaddr))) != NULL)
 177           memcpy(temp->ifa_broadaddr, &(request.ifr_broadaddr),
 178                  sizeof(request.ifr_broadaddr));
 179       }
 180     }
 181     else if (temp->ifa_flags & IFF_POINTOPOINT)
 182     {
 183      /*
 184       * Point-to-point interface; grab the remote address...
 185       */
 186
 187       if (!ioctl(sock, SIOCGIFDSTADDR, &request))
 188       {
 189         temp->ifa_dstaddr = malloc(sizeof(request.ifr_dstaddr));
 190         memcpy(temp->ifa_dstaddr, &(request.ifr_dstaddr),
 191                sizeof(request.ifr_dstaddr));
 192       }
 193     }
 194   }
 195
 196  /*
 197   * OK, we're done with the socket, close it and return 0...
 198   */
 199
 200   close(sock);
 201
 202   return (0);
 203 }
 204
 205
 206 /*
 207  * '_cups_freeifaddrs()' - Free an interface list...
 208  */
 209
 210 void
 211 _cups_freeifaddrs(struct ifaddrs *addrs)/* I - Interface list to free */
 212 {
 213   struct ifaddrs        *next;          /* Next interface in list */
 214
 215
 216   while (addrs != NULL)
 217   {
 218    /*
 219     * Make a copy of the next interface pointer...
 220     */
 221
 222     next = addrs->ifa_next;
 223
 224    /*
 225     * Free data values as needed...
 226     */
 227
 228     if (addrs->ifa_name)
 229     {
 230       free(addrs->ifa_name);
 231       addrs->ifa_name = NULL;
 232     }
 233
 234     if (addrs->ifa_addr)
 235     {
 236       free(addrs->ifa_addr);
 237       addrs->ifa_addr = NULL;
 238     }
 239
 240     if (addrs->ifa_netmask)
 241     {
 242       free(addrs->ifa_netmask);
 243       addrs->ifa_netmask = NULL;
 244     }
 245
 246     if (addrs->ifa_dstaddr)
 247     {
 248       free(addrs->ifa_dstaddr);
 249       addrs->ifa_dstaddr = NULL;
 250     }
 251
 252    /*
 253     * Free this node and continue to the next...
 254     */
 255
 256     free(addrs);
 257
 258     addrs = next;
 259   }
 260 }
 261 #endif /* !HAVE_GETIFADDRS */
 262
 263
 264 /*
 265  * End of "$Id$".
 266  */