cups/getifaddrs.c

   1 /*
   2  * "$Id: getifaddrs.c 177 2006-06-21 00:20:03Z jlovell $"
   3  *
   4  *   Network interface functions for the Common UNIX Printing System
   5  *   (CUPS) scheduler.
   6  *
   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 Easy Software Products and are protected by Federal
  11  *   copyright law.  Distribution and use rights are outlined in the file
  12  *   "LICENSE" which should have been included with this file.  If this
  13  *   file is missing or damaged please contact Easy Software Products
  14  *   at:
  15  *
  16  *       Attn: CUPS Licensing Information
  17  *       Easy Software Products
  18  *       44141 Airport View Drive, Suite 204
  19  *       Hollywood, Maryland 20636 USA
  20  *
  21  *       Voice: (301) 373-9600
  22  *       EMail: cups-info@cups.org
  23  *         WWW: http://www.cups.org
  24  *
  25  * Contents:
  26  *
  27  *   _cups_getifaddrs()  - Get a list of network interfaces on the system.
  28  *   _cups_freeifaddrs() - Free an interface list...
  29  */
  30
  31 /*
  32  * Include necessary headers.
  33  */
  34
  35 #include "http-private.h"
  36
  37
  38 #ifndef HAVE_GETIFADDRS
  39 /*
  40  * '_cups_getifaddrs()' - Get a list of network interfaces on the system.
  41  */
  42
  43 int                                     /* O - 0 on success, -1 on error */
  44 _cups_getifaddrs(struct ifaddrs **addrs)/* O - List of interfaces */
  45 {
  46   int                   sock;           /* Socket */
  47   char                  buffer[65536],  /* Buffer for address info */
  48                         *bufptr,        /* Pointer into buffer */
  49                         *bufend;        /* End of buffer */
  50   struct ifconf         conf;           /* Interface configurations */
  51   struct sockaddr       addr;           /* Address data */
  52   struct ifreq          *ifp;           /* Interface data */
  53   int                   ifpsize;        /* Size of interface data */
  54   struct ifaddrs        *temp;          /* Pointer to current interface */
  55   struct ifreq          request;        /* Interface request */
  56
  57
  58  /*
  59   * Start with an empty list...
  60   */
  61
  62   if (addrs == NULL)
  63     return (-1);
  64
  65   *addrs = NULL;
  66
  67  /*
  68   * Create a UDP socket to get the interface data...
  69   */
  70
  71   memset (&addr, 0, sizeof(addr));
  72   if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
  73     return (-1);
  74
  75  /*
  76   * Try to get the list of interfaces...
  77   */
  78
  79   conf.ifc_len = sizeof(buffer);
  80   conf.ifc_buf = buffer;
  81
  82   if (ioctl(sock, SIOCGIFCONF, &conf) < 0)
  83   {
  84    /*
  85     * Couldn't get the list of interfaces...
  86     */
  87
  88     close(sock);
  89     return (-1);
  90   }
  91
  92  /*
  93   * OK, got the list of interfaces, now lets step through the
  94   * buffer to pull them out...
  95   */
  96
  97 #  ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
  98 #    define sockaddr_len(a)     ((a)->sa_len)
  99 #  else
 100 #    define sockaddr_len(a)     (sizeof(struct sockaddr))
 101 #  endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
 102
 103   for (bufptr = buffer, bufend = buffer + conf.ifc_len;
 104        bufptr < bufend;
 105        bufptr += ifpsize)
 106   {
 107    /*
 108     * Get the current interface information...
 109     */
 110
 111     ifp     = (struct ifreq *)bufptr;
 112     ifpsize = sizeof(ifp->ifr_name) + sockaddr_len(&(ifp->ifr_addr));
 113
 114     if (ifpsize < sizeof(struct ifreq))
 115       ifpsize = sizeof(struct ifreq);
 116
 117     memset(&request, 0, sizeof(request));
 118     memcpy(request.ifr_name, ifp->ifr_name, sizeof(ifp->ifr_name));
 119
 120    /*
 121     * Check the status of the interface...
 122     */
 123
 124     if (ioctl(sock, SIOCGIFFLAGS, &request) < 0)
 125       continue;
 126
 127    /*
 128     * Allocate memory for a single interface record...
 129     */
 130
 131     if ((temp = calloc(1, sizeof(struct ifaddrs))) == NULL)
 132     {
 133      /*
 134       * Unable to allocate memory...
 135       */
 136
 137       close(sock);
 138       return (-1);
 139     }
 140
 141    /*
 142     * Add this record to the front of the list and copy the name, flags,
 143     * and network address...
 144     */
 145
 146     temp->ifa_next  = *addrs;
 147     *addrs          = temp;
 148     temp->ifa_name  = strdup(ifp->ifr_name);
 149     temp->ifa_flags = request.ifr_flags;
 150     if ((temp->ifa_addr = calloc(1, sockaddr_len(&(ifp->ifr_addr)))) != NULL)
 151       memcpy(temp->ifa_addr, &(ifp->ifr_addr), sockaddr_len(&(ifp->ifr_addr)));
 152
 153    /*
 154     * Try to get the netmask for the interface...
 155     */
 156
 157     if (!ioctl(sock, SIOCGIFNETMASK, &request))
 158     {
 159      /*
 160       * Got it, make a copy...
 161       */
 162
 163       if ((temp->ifa_netmask = calloc(1, sizeof(request.ifr_netmask))) != NULL)
 164         memcpy(temp->ifa_netmask, &(request.ifr_netmask),
 165                sizeof(request.ifr_netmask));
 166     }
 167
 168    /*
 169     * Then get the broadcast or point-to-point (destination) address,
 170     * if applicable...
 171     */
 172
 173     if (temp->ifa_flags & IFF_BROADCAST)
 174     {
 175      /*
 176       * Have a broadcast address, so get it!
 177       */
 178
 179       if (!ioctl(sock, SIOCGIFBRDADDR, &request))
 180       {
 181        /*
 182         * Got it, make a copy...
 183         */
 184
 185         if ((temp->ifa_broadaddr =
 186                  calloc(1, sizeof(request.ifr_broadaddr))) != NULL)
 187           memcpy(temp->ifa_broadaddr, &(request.ifr_broadaddr),
 188                  sizeof(request.ifr_broadaddr));
 189       }
 190     }
 191     else if (temp->ifa_flags & IFF_POINTOPOINT)
 192     {
 193      /*
 194       * Point-to-point interface; grab the remote address...
 195       */
 196
 197       if (!ioctl(sock, SIOCGIFDSTADDR, &request))
 198       {
 199         temp->ifa_dstaddr = malloc(sizeof(request.ifr_dstaddr));
 200         memcpy(temp->ifa_dstaddr, &(request.ifr_dstaddr),
 201                sizeof(request.ifr_dstaddr));
 202       }
 203     }
 204   }
 205
 206  /*
 207   * OK, we're done with the socket, close it and return 0...
 208   */
 209
 210   close(sock);
 211
 212   return (0);
 213 }
 214
 215
 216 /*
 217  * '_cups_freeifaddrs()' - Free an interface list...
 218  */
 219
 220 void
 221 _cups_freeifaddrs(struct ifaddrs *addrs)/* I - Interface list to free */
 222 {
 223   struct ifaddrs        *next;          /* Next interface in list */
 224
 225
 226   while (addrs != NULL)
 227   {
 228    /*
 229     * Make a copy of the next interface pointer...
 230     */
 231
 232     next = addrs->ifa_next;
 233
 234    /*
 235     * Free data values as needed...
 236     */
 237
 238     if (addrs->ifa_name)
 239     {
 240       free(addrs->ifa_name);
 241       addrs->ifa_name = NULL;
 242     }
 243
 244     if (addrs->ifa_addr)
 245     {
 246       free(addrs->ifa_addr);
 247       addrs->ifa_addr = NULL;
 248     }
 249
 250     if (addrs->ifa_netmask)
 251     {
 252       free(addrs->ifa_netmask);
 253       addrs->ifa_netmask = NULL;
 254     }
 255
 256     if (addrs->ifa_dstaddr)
 257     {
 258       free(addrs->ifa_dstaddr);
 259       addrs->ifa_dstaddr = NULL;
 260     }
 261
 262    /*
 263     * Free this node and continue to the next...
 264     */
 265
 266     free(addrs);
 267
 268     addrs = next;
 269   }
 270 }
 271 #endif /* !HAVE_GETIFADDRS */
 272
 273
 274 /*
 275  * End of "$Id: getifaddrs.c 177 2006-06-21 00:20:03Z jlovell $".
 276  */