contrib/ipfilter/ipsend/larp.c

   1 /*
   2  * larp.c (C) 1995-1998 Darren Reed
   3  *
   4  * See the IPFILTER.LICENCE file for details on licencing.
   5  */
   6 #if !defined(lint)
   7 static const char sccsid[] = "@(#)larp.c        1.1 8/19/95 (C)1995 Darren Reed";
   8 static const char rcsid[] = "@(#)$Id: larp.c,v 2.1.4.1 2001/06/26 10:43:22 darrenr Exp $";
   9 #endif
  10 #include <stdio.h>
  11 #include <errno.h>
  12 #include <sys/types.h>
  13 #include <sys/socket.h>
  14 #include <sys/ioctl.h>
  15 #include <netdb.h>
  16 #include <netinet/in.h>
  17 #include <net/if.h>
  18 #include <net/if_arp.h>
  19
  20 #include "ip_compat.h"
  21 #include "iplang/iplang.h"
  22
  23 /*
  24  * lookup host and return
  25  * its IP address in address
  26  * (4 bytes)
  27  */
  28 int     resolve(host, address)
  29 char    *host, *address;
  30 {
  31         struct  hostent *hp;
  32         u_long  add;
  33
  34         add = inet_addr(host);
  35         if (add == -1)
  36             {
  37                 if (!(hp = gethostbyname(host)))
  38                     {
  39                         fprintf(stderr, "unknown host: %s\n", host);
  40                         return -1;
  41                     }
  42                 bcopy((char *)hp->h_addr, (char *)address, 4);
  43                 return 0;
  44         }
  45         bcopy((char*)&add, address, 4);
  46         return 0;
  47 }
  48
  49 /*
  50  * ARP for the MAC address corresponding
  51  * to the IP address.  This taken from
  52  * some BSD program, I cant remember which.
  53  */
  54 int     arp(ip, ether)
  55 char    *ip;
  56 char    *ether;
  57 {
  58         static  int     s = -1;
  59         struct  arpreq  ar;
  60         struct  sockaddr_in     *sin;
  61         char    *inet_ntoa();
  62
  63 #ifdef  IP_SEND
  64         if (arp_getipv4(ip, ether) == 0)
  65                 return 0;
  66 #endif
  67         bzero((char *)&ar, sizeof(ar));
  68         sin = (struct sockaddr_in *)&ar.arp_pa;
  69         sin->sin_family = AF_INET;
  70         bcopy(ip, (char *)&sin->sin_addr.s_addr, 4);
  71
  72         if (s == -1)
  73                 if ((s = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
  74                     {
  75                         perror("arp: socket");
  76                         return -1;
  77                     }
  78
  79         if (ioctl(s, SIOCGARP, (caddr_t)&ar) == -1)
  80             {
  81                 fprintf(stderr, "(%s):", inet_ntoa(sin->sin_addr));
  82                 if (errno != ENXIO)
  83                         perror("SIOCGARP");
  84                 return -1;
  85             }
  86
  87         bcopy(ar.arp_ha.sa_data, ether, 6);
  88         return 0;
  89 }