NetBSD/usr.sbin/ipf/ipsend/44arp.c

96 lines
1.8 KiB
C

/*
* Based upon 4.4BSD's /usr/sbin/arp
*/
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <sys/param.h>
#include <sys/file.h>
#include <sys/socket.h>
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_types.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <errno.h>
#include <nlist.h>
#include <stdio.h>
/*
* lookup host and return
* its IP address in address
* (4 bytes)
*/
int resolve(host, address)
char *host, *address;
{
struct hostent *hp;
u_long add;
add = inet_addr(host);
if (add == -1)
{
if (!(hp = gethostbyname(host)))
{
fprintf(stderr, "unknown host: %s\n", host);
return -1;
}
bcopy((char *)hp->h_addr, (char *)address, 4);
return 0;
}
bcopy((char*)&add, address, 4);
return 0;
}
int arp(addr, eaddr)
char *addr, *eaddr;
{
int mib[6];
size_t needed;
char *malloc(), *lim, *buf, *next;
struct rt_msghdr *rtm;
struct sockaddr_inarp *sin;
struct sockaddr_dl *sdl;
mib[0] = CTL_NET;
mib[1] = PF_ROUTE;
mib[2] = 0;
mib[3] = AF_INET;
mib[4] = NET_RT_FLAGS;
mib[5] = RTF_LLINFO;
if (sysctl(mib, 6, NULL, &needed, NULL, 0) == -1)
{
perror("route-sysctl-estimate");
exit(-1);
}
if ((buf = malloc(needed)) == NULL)
{
perror("malloc");
exit(-1);
}
if (sysctl(mib, 6, buf, &needed, NULL, 0) == -1)
{
perror("actual retrieval of routing table");
exit(-1);
}
lim = buf + needed;
for (next = buf; next < lim; next += rtm->rtm_msglen)
{
rtm = (struct rt_msghdr *)next;
sin = (struct sockaddr_inarp *)(rtm + 1);
sdl = (struct sockaddr_dl *)(sin + 1);
if (addr && !bcmp(addr, (char *)&sin->sin_addr,
sizeof(struct in_addr)))
{
bcopy(LLADDR(sdl), eaddr, sdl->sdl_alen);
return 0;
}
}
return -1;
}