Redes_Scanner.c

#include <arpa/inet.h>
#include <linux/if_packet.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <net/if.h>
#include <netinet/ether.h>
#include <my_global.h>
#include <mysql.h>

int indice;
unsigned char trama[1514], tramaResp[1514];                             // Declara Trama
unsigned char MACDestino[] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };    // Broadcast
unsigned char MACOrigen[6], IPOrigen[4];
unsigned char etherType[] = { 0x08, 0x06 };                             // Define ARP
unsigned char arpData[] = { 0x00, 0x01, 0x08, 0x00, 0x06, 0x04, 0x00, 0x01 };
unsigned char arpTarget[] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };

unsigned char arpTargetIP[] = { 0xc0, 0xa8, 0x00, 0x61 };
unsigned char respIP[4], respMAC[6];

void enviarTrama(int ds, unsigned char * trama){
	struct sockaddr_ll interfaz;

	//Reseteamos la struct
	memset(&interfaz, 0, sizeof(interfaz));
	interfaz.sll_family = AF_PACKET;
	interfaz.sll_protocol = htons(ETH_P_ALL);
	interfaz.sll_ifindex = indice;

	if (sendto(ds, trama, 60, 0, (struct sockaddr *)&interfaz, sizeof(interfaz)) < 0) printf("Error al enviar");
	//else printf("\nExito al enviar\n");
}

void estrTrama(unsigned char * raw, unsigned char digit){
	memcpy(raw + 0, MACDestino, 6);
	memcpy(raw + 6, MACOrigen, 6);
	memcpy(raw + 12, etherType, 2); // ARP
	memcpy(raw + 14, arpData, 8);
	memcpy(raw + 22, MACOrigen, 6);
	memcpy(raw + 28, IPOrigen, 4);
	memcpy(raw + 32, arpTarget, 6);
	memcpy(arpTargetIP, IPOrigen, 4);

	arpTargetIP[3] = digit;
	memcpy(raw + 38, arpTargetIP, 4);
}

void imprimeDatos(){
	int i;

	printf("Indice: %d\n", indice);
	printf("Dir MAC: ");
	for (i = 0; i < 6; i++) {
		printf("%.2x", MACOrigen[i]);
		if (i != 5) printf(":");
	}
	printf("\nDir IP: ");
	for (i = 0; i < 4; i++) {
		printf("%d", IPOrigen[i]);
		if (i != 3) printf(".");
	}
	printf("\n");
}
void obtenerDatos(int ds, struct ifreq net){

	if (ioctl(ds, SIOCGIFINDEX, &net) < 0) perror("Error al obtener el indice");
	else indice = net.ifr_ifindex;
	if (ioctl(ds, SIOCGIFHWADDR, &net) < 0) perror("Error MAC");
	else memcpy(MACOrigen, net.ifr_hwaddr.sa_data, 6);
	if (ioctl(ds, SIOCGIFADDR, &net) < 0) perror("Error IP");
	else memcpy(IPOrigen, net.ifr_hwaddr.sa_data + 2, 4);
}

int intento = 0;
int recibirTrama(int ds, unsigned char * tramaResp){
	unsigned char server_reply[6000];
	int i = 0, j = 0, success = 0;
	ssize_t numbytes;

	numbytes = recvfrom(ds, server_reply, 6000, 0, NULL, NULL);
	if (numbytes > 0) {
		printf("Recibi algo. Tamaño %lu bytes. ", numbytes);
		if (server_reply[0] == MACOrigen[0] &&
		    server_reply[1] == MACOrigen[1] &&
		    server_reply[2] == MACOrigen[2] &&
		    server_reply[3] == MACOrigen[3] &&
		    server_reply[4] == MACOrigen[4] &&
		    server_reply[5] == MACOrigen[5] ) {
			printf("DST Correcto. ");
			/* Print packet
			   printf("\tData:");
			   for (i=0; i<numbytes; i++) printf("%02x:", server_reply[i]);*/
			if (server_reply[12] == 0x08 && server_reply[13] == 0x06) {
				printf("\n\tPackete recibido es ARP... " );
				if (server_reply[21] == 0x02) {
					printf("Tipo Respuesta! Verificando...\n" );
					if (server_reply[28] == arpTargetIP[0] &&
					    server_reply[29] == arpTargetIP[1] &&
					    server_reply[30] == arpTargetIP[2] &&
					    server_reply[31] == arpTargetIP[3]
					    ) {
						memcpy(respIP, server_reply + 28, 4);
						memcpy(respMAC, server_reply + 22, 6);
						success = 1;
					}
				}
			}else
				printf("Packete recibido no es ARP. Buscando...\n" );
		}else
			printf("DST: %.2x:%.2x:%.2x:%.2x:%.2x:%.2x\n", server_reply[0], server_reply[1], server_reply[2], server_reply[3], server_reply[4], server_reply[5]);
	}else{
		printf("Timed Out\n");
		intento++;
	}
	return success;
}

void finish_with_error(MYSQL *con){
	fprintf(stderr, "%s\n", mysql_error(con));
	mysql_close(con);
	exit(1);
}

int main(int argc, char *argv[]){
	MYSQL *con = mysql_init(NULL);
	int packet_socket, j, resp = 0;
	struct ifreq net;
	unsigned char digit = 0x00;
	char resultadoIP[15], resultadoMAC[18], query[500];

	if (con == NULL) {
		fprintf(stderr, "%s\n", mysql_error(con));
		exit(1);
	}
	if (mysql_real_connect(con, "localhost", "root", "root", "MAC", 0, NULL, 0) == NULL) finish_with_error(con);
	if ((packet_socket = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ALL))) == -1)
		perror("Error en el socket");
	else{
		printf("Exito al abrir el socket\n");

		struct timeval tv;

		tv.tv_sec = 0;          /* 30 Secs Timeout */
		tv.tv_usec = 10000;     // Not init'ing this can cause strange errors

		setsockopt(packet_socket, SOL_SOCKET, SO_RCVTIMEO, (char*)&tv, sizeof(struct timeval));

		if (argc > 1)
			strcpy(net.ifr_name, argv[1]);
		else{
			printf("Introduzca nombre de la interfaz: ");
			scanf("%s", net.ifr_name);
		}

		obtenerDatos(packet_socket, net);
		imprimeDatos();
		//imprimeTrama(trama)
		for (j = 0; j < 255; j++) {
			digit += 0x01; intento = 0, resp = 0;
			estrTrama(trama, digit);
			enviarTrama(packet_socket, trama);
			printf("[Query] Buscando IP %d.%d.%d.%d\n", arpTargetIP[0], arpTargetIP[1], arpTargetIP[2], arpTargetIP[3]);
			while (!resp && intento < 10) {
				printf("\tIntento #%d: ", intento + 1);
				resp = recibirTrama(packet_socket, tramaResp);
			}
			if (intento == 10) printf("[Error] No se encontro. %d.%d.%d.%d\n", arpTargetIP[0], arpTargetIP[1], arpTargetIP[2], arpTargetIP[3]);
			else {
				sprintf(resultadoIP, "%d.%d.%d.%d", respIP[0], respIP[1], respIP[2], respIP[3]);
				sprintf(resultadoMAC, "%.2x:%.2x:%.2x:%.2x:%.2x:%.2x", respMAC[0], respMAC[1], respMAC[2], respMAC[3], respMAC[4], respMAC[5]);
				printf("[Resp!] Almacenando: %s = MAC: %s\n", resultadoIP, resultadoMAC);
				sprintf(query, "INSERT INTO dir VALUES(NULL,'%s','%s')", resultadoIP, resultadoMAC);
				if (mysql_query(con, query)) finish_with_error(con);
			}
		}
		mysql_close(con);
		return 0;
	}


}