/* -----------------------------------------
gcc -o arptoip arptoip.c
mac address to ip --by sztcww
*/
#include　　　　<sys/types.h>　 /* basic system data types */
#include　　　　<sys/socket.h>　/* basic socket definitions */
#include　　　　<sys/time.h>　　/* timeval{} for select() */
#include　　　　<time.h>　　　　　　　　/* timespec{} for pselect() */
#include　　　　<netinet/in.h>　/* sockaddr_in{} and other Internet defns */
#include　　　　<arpa/inet.h>　 /* inet(3) functions */
#include　　　　<errno.h>
#include　　　　<fcntl.h>　　　　　　　 /* for nonblocking */
#include　　　　<netdb.h>
#include　　　　<signal.h>
#include　　　　<stdio.h>
#include　　　　<stdlib.h>
#include　　　　<string.h>
#include　　　　<sys/stat.h>　　/* for S_xxx file mode constants */
#include　　　　<sys/uio.h>　　　　　　 /* for iovec{} and readv/writev */
#include　　　　<unistd.h>
#include　　　　<sys/wait.h>
#include　　　　<sys/un.h>　　　　　　　/* for Unix domain sockets */
#include <netdb.h>
#include <sys/ioctl.h>
#include <stdarg.h>
#include <net/if.h>
#include <netinet/ip.h>
#define __FAVOR_BSD
#include <netinet/tcp.h>
#define ETH_P_ARP 0x0806
#define MAX_PACK_LEN 2000
#define ETHER_HEADER_LEN 14
#define ARPREQUEST 1
#define ARPREPLY 2
#define perr(s) fprintf(stderr,s)
struct arp_struct
{
u_char dst_mac[6];
u_char src_mac[6];
u_short pkt_type;
u_short hw_type;
u_short pro_type;
u_char hw_len;
u_char pro_len;
u_short arp_op;
u_char sender_eth[6];
u_char sender_ip[4];
u_char target_eth[6];
u_char target_ip[4];
};
union
{
u_char full_packet[MAX_PACK_LEN];
struct arp_struct arp_pkt;
}
a;
#define full_packet a.full_packet
#define arp_pkt a.arp_pkt
void get_hw_addr (char *, char *);
char *
inetaddr ( u_int32_t ip )
{
struct in_addr in;
in.s_addr = ip;
return inet_ntoa(in);
}
char *
hwaddr (u_char * s)
{
static char buf[30];
sprintf (buf, "%02X:%02X:%02X:%02X:%02X:%02X", s[0], s[1], s[2], s[3],
s[4], s[5]);
return buf;
}
int
main (int argc, char **argv)
{
int rec;
int len, from_len, rsflags;
struct ifreq if_data;
struct sockaddr from;
u_int8_t myMAC[6];
u_int32_t myIP, myNETMASK, myBROADCAST, ip, dip, sip;
char * macaddr;
if (getuid () != 0)
{
perr ("You must be root to run this program!\n");
exit (0);
}
if (argc != 2)
{
fprintf(stderr,"Usage: %s Macaddr\n", argv[0]);
exit (0);
}
if ((rec = socket (AF_INET, SOCK_PACKET, htons (ETH_P_ARP))) < 0)
{
perror("socket");
exit (0);
}
printf ("----------------------------------------------------------\n");
strcpy (if_data.ifr_name, "eth0");
if (ioctl (rec, SIOCGIFHWADDR, &if_data) < 0) {
perr ("can't get HW addres of my interface!\n");
exit(1);
}
memcpy (myMAC, if_data.ifr_hwaddr.sa_data, 6);
printf ("> My HW Addr: %s\n", hwaddr (myMAC));
if (ioctl (rec, SIOCGIFADDR, &if_data) < 0) {
perr ("can't get IP addres of my interface!\n");
exit(1);
}
memcpy ((void *) &ip, (void *) &if_data.ifr_addr.sa_data + 2, 4);
myIP = ntohl (ip);
printf ("> My IP Addr: %s\n", inetaddr(ip));
if (ioctl (rec, SIOCGIFNETMASK, &if_data) < 0)
perr ("can't get NETMASK addres of my interface!\n");
memcpy ((void *) &ip, (void *) &if_data.ifr_netmask.sa_data + 2, 4);
myNETMASK = ntohl (ip);
printf ("> My NETMASK: %s\n", inetaddr(ip));
if (ioctl (rec, SIOCGIFBRDADDR, &if_data) < 0)
perr ("can't get BROADCAST addres of my interface!\n");
memcpy ((void *) &ip, (void *) &if_data.ifr_broadaddr.sa_data + 2, 4);
myBROADCAST = ntohl (ip);
printf ("> My BROADCAST: %s\n", inetaddr(ip));
if ((rsflags = fcntl (rec, F_GETFL)) == -1)
{
perror ("fcntl F_GETFL");
exit (1);
}
if (fcntl (rec, F_SETFL, rsflags | O_NONBLOCK) == -1)
{
perror ("fcntl F_SETFL");
exit (1);
}
printf ("----------------------------------------------------------\n");
printf ("Scanning");
for (dip = (myIP & myNETMASK) + 1; dip < myBROADCAST; dip++)
{
bzero(full_packet, MAX_PACK_LEN);
//memcpy (arp_pkt.dst_mac,"\255\255\255\255\255\0", 6); 
memcpy (arp_pkt.dst_mac, "\xff\xff\xff\xff\xff\xff", 6); 
　　　　//get_hw_addr(arp_pkt.dst_mac,"FF:FF:FF:FF:FF:FF");
/* ff:ff:ff:ff:ff:ff:)*/
memcpy (arp_pkt.src_mac, myMAC, 6);
arp_pkt.pkt_type = htons( ETH_P_ARP );
arp_pkt.hw_type = htons( 0x0001 );
arp_pkt.hw_len = 6;
arp_pkt.pro_type = htons( 0x0800 );
arp_pkt.pro_len = 4;
arp_pkt.arp_op = htons (ARPREQUEST);
memcpy (arp_pkt.sender_eth, myMAC, 6);
ip = htonl (myIP);
memcpy (arp_pkt.sender_ip, &ip, 4);
memcpy (arp_pkt.target_eth, "\0\0\0\0\0\0", 6);
ip = htonl (dip);
memcpy (arp_pkt.target_ip, &ip, 4);
strcpy(from.sa_data, "eth0");
from.sa_family = 1;
if( sendto (rec, full_packet, sizeof (struct arp_struct), 0, &from,sizeof(from)) < 0)
perror ("sendto");
usleep (50);
len = recvfrom (rec, full_packet, MAX_PACK_LEN, 0, &from, &from_len);
if (len <= ETHER_HEADER_LEN)
continue;
memcpy (&ip, arp_pkt.target_ip, 4);
memcpy (&sip, arp_pkt.sender_ip, 4);

if (ntohs (arp_pkt.arp_op) == ARPREPLY
&& ( dip - ntohl(sip) >= 0 )
&& ( dip - ntohl(sip) <= 2 ) )
{
macaddr=hwaddr(arp_pkt.sender_eth);
if (!strncmp(macaddr,argv[1],17))
{
printf ("\nMAC: %s ---------> HOST: %s \n",macaddr,inetaddr (sip));
exit(0);
}
}else 
printf("."),fflush(stdout);


}
printf ("End\n");
return;
}
void get_hw_addr (char *buf, char *str)
　　　　{
　　　　int i;
　　　　char c, val;
　　　　for(i = 0; i < 6; i++)
　　　　{
　　　　if (!(c = tolower(*str++)));
　　　　if (isdigit(c))
　　　　　　　　val = c - '0';
　　　　else if (c >= 'a' && c <= 'f')
　　　　　　　　val = c-'a'+10;
　　　　*buf = val << 4;
　　　　if (!(c = tolower(*str++)));
　　　　if (isdigit(c))
　　　　　　　　val = c - '0';
　　　　else if (c >= 'a' && c <= 'f')
　　　　　　　　val = c-'a'+10;
　　　　*buf++ |= val;
　 if (*str == ':')
　　　　　　　　str++;
　　　　}
　　　　}