/* Thanks to crazyc for the packet replay code basics */

#include <arpa/inet.h>
#include <net/ethernet.h>
#include <net/if.h>
#include <net/if_arp.h>
#include <netinet/in.h>
#include <netpacket/packet.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/uio.h>
#include <sys/ioctl.h>
#include <errno.h>
#include <pcap.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>

typedef unsigned char __u8;
typedef unsigned short __u16;
#include "80211.h"

struct llc_hdr {
    __u8        dsap;
    __u8        ssap;
    __u8        cntl;
    __u8        org_code[3];
    __u16       type;
} __attribute__ ((packed));

int initialize(char *device, int sd, int promisc) {
	struct ifreq ifr;
	
	strncpy(ifr.ifr_name, device, sizeof(ifr.ifr_name));
	if (ioctl(sd, SIOCGIFFLAGS, &ifr)<0) {
		perror("SIOCGIFFLAGS");
		return -1;
	}
	
	if (promisc)
		ifr.ifr_flags |= IFF_PROMISC;
	else
		ifr.ifr_flags &= ~IFF_PROMISC;
	
	if(ioctl(sd, SIOCSIFFLAGS, &ifr)<0) {
		perror("SIOCSIFFLAGS");
		return -1;
	}
	
	printf("Initialized device %s\n", device);
	
	if (ioctl(sd, SIOCGIFINDEX, &ifr)<0) {
		perror("SIOCGIFINDEX");
		return -1;
	}
	
	return ifr.ifr_ifindex;
}

void shutdownDevices() {
	printf("User shutdown\n");

	exit(0);
}

void printMAC(u_char *mac) {
	int i;
	printf("%.2x", mac[0]);
	for (i = 1; i < ETH_ALEN; i++) {
		printf(":%.2x", mac[i]);
	}
}

int main(int argc, char **argv) {
//	const u_char startMAC[8] = {0x00, 0x09, 0xBF, 0x0A, 0xF1, 0x86, 0, 0};
	const u_char startMAC[8] = {0x00, 0x09, 0xBF, 0x0B, 0x79, 0xB0, 0, 0};
	struct ethhdr *ethHeader;
	struct sockaddr_ll etherSocket;
	int sd;
	int ethIndex;
	u_char packet[65535];
	u_char sendPacket[65535];

	signal(SIGINT, shutdownDevices);
	signal(SIGQUIT, shutdownDevices);

	// Set up raw sockets for sending
	sd = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_ALL));
	if (sd < 0) {
		printf("Couldn't create packet socket :(\n");
		return 1;
	}

	if ((ethIndex = initialize("ath0", sd, 1)) < 0) {
		printf("Couldn't find adapter.\n");
		return 1;
	}

/*	// Set the MAC address to our starting one
	struct ifreq req;
	strcpy(req.ifr_name, "ath0");
	req.ifr_hwaddr.sa_family = ARPHRD_ETHER;
	memcpy(req.ifr_hwaddr.sa_data, startMAC, 6);		
	
	if (ioctl(sd, SIOCSIFHWADDR, &req) < 0) {
		printf("Unable to set MAC address %d.\n",errno);
		return 1;
	}*/

	// Bind the socket to the interface
	memset(&etherSocket, 0, sizeof(etherSocket));
	etherSocket.sll_family = AF_PACKET;
	etherSocket.sll_protocol = htons(ETH_P_ALL);
	etherSocket.sll_ifindex = ethIndex;

	if (bind(sd, (struct sockaddr *)&etherSocket, sizeof(etherSocket)) < 0) {
		printf("Couldn't bind socket.\n");
		return 1;
	}

	char errbuf[512];
	errbuf[0] = 0;
    pcap_t *cap_file = pcap_open_offline("mariobeaconsmod", errbuf);
	if (errbuf[0] != 0) printf("Warning: %s\n",errbuf);
    if (!cap_file) {
		printf("Error opening packet file: %s\n",errbuf);
    	return 1;
	}

	#define DLT_80211_PRISM 0x77
	int header_offset = 0;
    if (pcap_datalink(cap_file) == DLT_80211_PRISM) {
		header_offset = 144;
	}
	printf("Header offset: %d\n", header_offset);

    struct pcap_pkthdr *header;
    const u_char *frame;
    if(pcap_next_ex(cap_file, &header, &frame) < 1) {
		printf("Unable to read packet.\n");
		return 1;
	}
			
    struct timeval lasttime;
    struct timespec delay;

    lasttime.tv_sec = header->ts.tv_sec;
    lasttime.tv_usec = header->ts.tv_usec;

    do {
		if(lasttime.tv_usec > header->ts.tv_usec) {
  			lasttime.tv_usec -= 1000000;
  			lasttime.tv_sec++;
 		}
 		delay.tv_sec = header->ts.tv_sec - lasttime.tv_sec;
 		delay.tv_nsec = (header->ts.tv_usec - lasttime.tv_usec) * 1000;
 		nanosleep(&delay, NULL);
 		lasttime.tv_sec = header->ts.tv_sec;
 		lasttime.tv_usec = header->ts.tv_usec;
 		
		memset(&etherSocket, 0, sizeof(etherSocket));
		etherSocket.sll_family = AF_PACKET;
		etherSocket.sll_ifindex = ethIndex;
		memcpy(etherSocket.sll_addr, startMAC, 8);
		etherSocket.sll_halen = 6;

		printf("%d\n",header->len - header_offset - 4);
		if (sendto(sd, frame + header_offset, header->len - header_offset - 4, 0, (struct sockaddr *)&etherSocket, sizeof(etherSocket)) == -1) {
			printf("Error in sending packet.\n");
			return 1;
		}
    } while(pcap_next_ex(cap_file, &header, &frame) == 1); 
	
	return 0;
}