cups/getifaddrs.c

   1 /*
   2  * "$Id: getifaddrs.c 6649 2007-07-11 21:46:42Z mike $"
   3  *
   4  *   Network interface functions for the Common UNIX Printing System
   5  *   (CUPS) scheduler.
   6  *
   7  *   Copyright 2007 by Apple Inc.
   8  *   Copyright 1997-2006 by Easy Software Products, all rights reserved.
   9  *
  10  *   These coded instructions, statements, and computer programs are the
  11  *   property of Apple Inc. and are protected by Federal copyright
  12  *   law.  Distribution and use rights are outlined in the file "LICENSE.txt"
  13  *   "LICENSE" which should have been included with this file.  If this
  14  *   file is missing or damaged, see the license at "http://www.cups.org/".
  15  *
  16  * Contents:
  17  *
  18  *   _cups_getifaddrs()  - Get a list of network interfaces on the system.
  19  *   _cups_freeifaddrs() - Free an interface list...
  20  */
  21
  22 /*
  23  * Include necessary headers.
  24  */
  25
  26 #include "http-private.h"
  27
  28
  29 #ifndef HAVE_GETIFADDRS
  30 /*
  31  * '_cups_getifaddrs()' - Get a list of network interfaces on the system.
  32  */
  33
  34 int                                     /* O - 0 on success, -1 on error */
  35 _cups_getifaddrs(struct ifaddrs **addrs)/* O - List of interfaces */
  36 {
  37   int                   sock;           /* Socket */
  38   char                  buffer[65536],  /* Buffer for address info */
  39                         *bufptr,        /* Pointer into buffer */
  40                         *bufend;        /* End of buffer */
  41   struct ifconf         conf;           /* Interface configurations */
  42   struct sockaddr       addr;           /* Address data */
  43   struct ifreq          *ifp;           /* Interface data */
  44   int                   ifpsize;        /* Size of interface data */
  45   struct ifaddrs        *temp;          /* Pointer to current interface */
  46   struct ifreq          request;        /* Interface request */
  47
  48
  49  /*
  50   * Start with an empty list...
  51   */
  52
  53   if (addrs == NULL)
  54     return (-1);
  55
  56   *addrs = NULL;
  57
  58  /*
  59   * Create a UDP socket to get the interface data...
  60   */
  61
  62   memset (&addr, 0, sizeof(addr));
  63   if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
  64     return (-1);
  65
  66  /*
  67   * Try to get the list of interfaces...
  68   */
  69
  70   conf.ifc_len = sizeof(buffer);
  71   conf.ifc_buf = buffer;
  72
  73   if (ioctl(sock, SIOCGIFCONF, &conf) < 0)
  74   {
  75    /*
  76     * Couldn't get the list of interfaces...
  77     */
  78
  79     close(sock);
  80     return (-1);
  81   }
  82
  83  /*
  84   * OK, got the list of interfaces, now lets step through the
  85   * buffer to pull them out...
  86   */
  87
  88 #  ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
  89 #    define sockaddr_len(a)     ((a)->sa_len)
  90 #  else
  91 #    define sockaddr_len(a)     (sizeof(struct sockaddr))
  92 #  endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
  93
  94   for (bufptr = buffer, bufend = buffer + conf.ifc_len;
  95        bufptr < bufend;
  96        bufptr += ifpsize)
  97   {
  98    /*
  99     * Get the current interface information...
 100     */
 101
 102     ifp     = (struct ifreq *)bufptr;
 103     ifpsize = sizeof(ifp->ifr_name) + sockaddr_len(&(ifp->ifr_addr));
 104
 105     if (ifpsize < sizeof(struct ifreq))
 106       ifpsize = sizeof(struct ifreq);
 107
 108     memset(&request, 0, sizeof(request));
 109     memcpy(request.ifr_name, ifp->ifr_name, sizeof(ifp->ifr_name));
 110
 111    /*
 112     * Check the status of the interface...
 113     */
 114
 115     if (ioctl(sock, SIOCGIFFLAGS, &request) < 0)
 116       continue;
 117
 118    /*
 119     * Allocate memory for a single interface record...
 120     */
 121
 122     if ((temp = calloc(1, sizeof(struct ifaddrs))) == NULL)
 123     {
 124      /*
 125       * Unable to allocate memory...
 126       */
 127
 128       close(sock);
 129       return (-1);
 130     }
 131
 132    /*
 133     * Add this record to the front of the list and copy the name, flags,
 134     * and network address...
 135     */
 136
 137     temp->ifa_next  = *addrs;
 138     *addrs          = temp;
 139     temp->ifa_name  = strdup(ifp->ifr_name);
 140     temp->ifa_flags = request.ifr_flags;
 141     if ((temp->ifa_addr = calloc(1, sockaddr_len(&(ifp->ifr_addr)))) != NULL)
 142       memcpy(temp->ifa_addr, &(ifp->ifr_addr), sockaddr_len(&(ifp->ifr_addr)));
 143
 144    /*
 145     * Try to get the netmask for the interface...
 146     */
 147
 148     if (!ioctl(sock, SIOCGIFNETMASK, &request))
 149     {
 150      /*
 151       * Got it, make a copy...
 152       */
 153
 154       if ((temp->ifa_netmask = calloc(1, sizeof(request.ifr_netmask))) != NULL)
 155         memcpy(temp->ifa_netmask, &(request.ifr_netmask),
 156                sizeof(request.ifr_netmask));
 157     }
 158
 159    /*
 160     * Then get the broadcast or point-to-point (destination) address,
 161     * if applicable...
 162     */
 163
 164     if (temp->ifa_flags & IFF_BROADCAST)
 165     {
 166      /*
 167       * Have a broadcast address, so get it!
 168       */
 169
 170       if (!ioctl(sock, SIOCGIFBRDADDR, &request))
 171       {
 172        /*
 173         * Got it, make a copy...
 174         */
 175
 176         if ((temp->ifa_broadaddr =
 177                  calloc(1, sizeof(request.ifr_broadaddr))) != NULL)
 178           memcpy(temp->ifa_broadaddr, &(request.ifr_broadaddr),
 179                  sizeof(request.ifr_broadaddr));
 180       }
 181     }
 182     else if (temp->ifa_flags & IFF_POINTOPOINT)
 183     {
 184      /*
 185       * Point-to-point interface; grab the remote address...
 186       */
 187
 188       if (!ioctl(sock, SIOCGIFDSTADDR, &request))
 189       {
 190         temp->ifa_dstaddr = malloc(sizeof(request.ifr_dstaddr));
 191         memcpy(temp->ifa_dstaddr, &(request.ifr_dstaddr),
 192                sizeof(request.ifr_dstaddr));
 193       }
 194     }
 195   }
 196
 197  /*
 198   * OK, we're done with the socket, close it and return 0...
 199   */
 200
 201   close(sock);
 202
 203   return (0);
 204 }
 205
 206
 207 /*
 208  * '_cups_freeifaddrs()' - Free an interface list...
 209  */
 210
 211 void
 212 _cups_freeifaddrs(struct ifaddrs *addrs)/* I - Interface list to free */
 213 {
 214   struct ifaddrs        *next;          /* Next interface in list */
 215
 216
 217   while (addrs != NULL)
 218   {
 219    /*
 220     * Make a copy of the next interface pointer...
 221     */
 222
 223     next = addrs->ifa_next;
 224
 225    /*
 226     * Free data values as needed...
 227     */
 228
 229     if (addrs->ifa_name)
 230     {
 231       free(addrs->ifa_name);
 232       addrs->ifa_name = NULL;
 233     }
 234
 235     if (addrs->ifa_addr)
 236     {
 237       free(addrs->ifa_addr);
 238       addrs->ifa_addr = NULL;
 239     }
 240
 241     if (addrs->ifa_netmask)
 242     {
 243       free(addrs->ifa_netmask);
 244       addrs->ifa_netmask = NULL;
 245     }
 246
 247     if (addrs->ifa_dstaddr)
 248     {
 249       free(addrs->ifa_dstaddr);
 250       addrs->ifa_dstaddr = NULL;
 251     }
 252
 253    /*
 254     * Free this node and continue to the next...
 255     */
 256
 257     free(addrs);
 258
 259     addrs = next;
 260   }
 261 }
 262 #endif /* !HAVE_GETIFADDRS */
 263
 264
 265 /*
 266  * End of "$Id: getifaddrs.c 6649 2007-07-11 21:46:42Z mike $".
 267  */