contrib/ipfilter/ipsend/44arp.c

   1 /*
   2  * Based upon 4.4BSD's /usr/sbin/arp
   3  */
   4 #if defined(__sgi) && (IRIX > 602)
   5 # include <sys/ptimers.h>
   6 #endif
   7 #include <unistd.h>
   8 #include <string.h>
   9 #include <stdlib.h>
  10 #include <sys/param.h>
  11 #include <sys/file.h>
  12 #include <sys/socket.h>
  13 #include <sys/sysctl.h>
  14 #include <net/if.h>
  15 #include <net/if_dl.h>
  16 #include <net/if_types.h>
  17 #include <net/route.h>
  18 #include <netinet/in.h>
  19 #include <netinet/if_ether.h>
  20 #include <arpa/inet.h>
  21 #include <netdb.h>
  22 #include <errno.h>
  23 #include <nlist.h>
  24 #include <stdio.h>
  25 #include <netinet/in.h>
  26 #include <netinet/ip_var.h>
  27 #include <netinet/tcp.h>
  28 #if __FreeBSD_version >= 300000
  29 # include <net/if_var.h>
  30 #endif
  31 #include "ipsend.h"
  32 #include "iplang/iplang.h"
  33
  34
  35 /*
  36  * lookup host and return
  37  * its IP address in address
  38  * (4 bytes)
  39  */
  40 int     resolve(host, address)
  41 char    *host, *address;
  42 {
  43         struct  hostent *hp;
  44         u_long  add;
  45
  46         add = inet_addr(host);
  47         if (add == -1)
  48             {
  49                 if (!(hp = gethostbyname(host)))
  50                     {
  51                         fprintf(stderr, "unknown host: %s\n", host);
  52                         return -1;
  53                     }
  54                 bcopy((char *)hp->h_addr, (char *)address, 4);
  55                 return 0;
  56         }
  57         bcopy((char*)&add, address, 4);
  58         return 0;
  59 }
  60
  61
  62 int     arp(addr, eaddr)
  63 char    *addr, *eaddr;
  64 {
  65         int     mib[6];
  66         size_t  needed;
  67         char    *lim, *buf, *next;
  68         struct  rt_msghdr       *rtm;
  69         struct  sockaddr_inarp  *sin;
  70         struct  sockaddr_dl     *sdl;
  71
  72 #ifdef  IPSEND
  73         if (arp_getipv4(addr, ether) == 0)
  74                 return 0;
  75 #endif
  76
  77         mib[0] = CTL_NET;
  78         mib[1] = PF_ROUTE;
  79         mib[2] = 0;
  80         mib[3] = AF_INET;
  81         mib[4] = NET_RT_FLAGS;
  82         mib[5] = RTF_LLINFO;
  83         if (sysctl(mib, 6, NULL, &needed, NULL, 0) == -1)
  84             {
  85                 perror("route-sysctl-estimate");
  86                 exit(-1);
  87             }
  88         if ((buf = malloc(needed)) == NULL)
  89             {
  90                 perror("malloc");
  91                 exit(-1);
  92             }
  93         if (sysctl(mib, 6, buf, &needed, NULL, 0) == -1)
  94             {
  95                 perror("actual retrieval of routing table");
  96                 exit(-1);
  97             }
  98         lim = buf + needed;
  99         for (next = buf; next < lim; next += rtm->rtm_msglen)
 100             {
 101                 rtm = (struct rt_msghdr *)next;
 102                 sin = (struct sockaddr_inarp *)(rtm + 1);
 103                 sdl = (struct sockaddr_dl *)(sin + 1);
 104                 if (addr && !bcmp(addr, (char *)&sin->sin_addr,
 105                                   sizeof(struct in_addr)))
 106                     {
 107                         bcopy(LLADDR(sdl), eaddr, sdl->sdl_alen);
 108                         return 0;
 109                     }
 110             }
 111         return -1;
 112 }