freebsd-dev/sbin/ipf/ipsend/arp.c
Cy Schubert 41edb306f0 ipfilter: Move userland bits to sbin
Through fixes and improvements our ipfilter sources have diverged
enough to warrant move from contrib into sbin/ipf. Now that I'm
planning on implementing MSS clamping as in iptables it makes more
sense to move ipfilter to sbin.

This is the second of three commits of the ipfilter move.

Suggested by glebius on two occaions.

Suggested by and discussed with:	glebius
Reviewed by:				glebius, kp (for #network)
MFC after:				1 month
Differential Revision:		https://reviews.freebsd.org/D33510
2021-12-20 06:16:33 -08:00

136 lines
2.9 KiB
C

/* $FreeBSD$ */
/*
* arp.c (C) 1995-1998 Darren Reed
*
* See the IPFILTER.LICENCE file for details on licencing.
*/
#if !defined(lint)
static const char sccsid[] = "@(#)arp.c 1.4 1/11/96 (C)1995 Darren Reed";
static const char rcsid[] = "@(#)$Id$";
#endif
#include <sys/types.h>
#include <sys/socket.h>
# include <sys/sockio.h>
#include <sys/ioctl.h>
#include <netinet/in_systm.h>
#include <netinet/in.h>
#include <net/if.h>
#include <netinet/if_ether.h>
# include <net/if_arp.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/tcp.h>
#include <stdio.h>
#include <errno.h>
#include <netdb.h>
#include "ipsend.h"
#include "iplang/iplang.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;
}
/*
* ARP for the MAC address corresponding
* to the IP address. This taken from
* some BSD program, I cant remember which.
*/
int arp(ip, ether)
char *ip;
char *ether;
{
static int sfd = -1;
static char ethersave[6], ipsave[4];
struct arpreq ar;
struct sockaddr_in *sin, san;
struct hostent *hp;
int fd;
#ifdef IPSEND
if (arp_getipv4(ip, ether) == 0)
return 0;
#endif
if (!bcmp(ipsave, ip, 4)) {
bcopy(ethersave, ether, 6);
return 0;
}
fd = -1;
bzero((char *)&ar, sizeof(ar));
sin = (struct sockaddr_in *)&ar.arp_pa;
sin->sin_family = AF_INET;
bcopy(ip, (char *)&sin->sin_addr.s_addr, 4);
if ((hp = gethostbyaddr(ip, 4, AF_INET)))
# if SOLARIS && (SOLARIS2 >= 10)
if (!(ether_hostton(hp->h_name, (struct ether_addr *)ether)))
# else
if (!(ether_hostton(hp->h_name, ether)))
# endif
goto savearp;
if (sfd == -1)
if ((sfd = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
{
perror("arp: socket");
return -1;
}
tryagain:
if (ioctl(sfd, SIOCGARP, (caddr_t)&ar) == -1)
{
if (fd == -1)
{
bzero((char *)&san, sizeof(san));
san.sin_family = AF_INET;
san.sin_port = htons(1);
bcopy(ip, &san.sin_addr.s_addr, 4);
fd = socket(AF_INET, SOCK_DGRAM, 0);
(void) sendto(fd, ip, 4, 0,
(struct sockaddr *)&san, sizeof(san));
sleep(1);
(void) close(fd);
goto tryagain;
}
fprintf(stderr, "(%s):", inet_ntoa(sin->sin_addr));
if (errno != ENXIO)
perror("SIOCGARP");
return -1;
}
if ((ar.arp_ha.sa_data[0] == 0) && (ar.arp_ha.sa_data[1] == 0) &&
(ar.arp_ha.sa_data[2] == 0) && (ar.arp_ha.sa_data[3] == 0) &&
(ar.arp_ha.sa_data[4] == 0) && (ar.arp_ha.sa_data[5] == 0)) {
fprintf(stderr, "(%s):", inet_ntoa(sin->sin_addr));
return -1;
}
bcopy(ar.arp_ha.sa_data, ether, 6);
savearp:
bcopy(ether, ethersave, 6);
bcopy(ip, ipsave, 4);
return 0;
}