/*
 * ZMap Copyright 2013 Regents of the University of Michigan
 *
 * XMap Copyright 2021 Xiang Li from Network and Information Security Lab
 * Tsinghua University
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy
 * of the License at http://www.apache.org/licenses/LICENSE-2.0
 */

#ifndef XMAP_SEND_LINUX_H
#define XMAP_SEND_LINUX_H

#include <netpacket/packet.h>
#include <sys/ioctl.h>

#include "../lib/includes.h"
#include "../lib/util.h"

#ifdef XMAP_SEND_BSD_H
#error "Don't include both send-bsd.h and send-linux.h"
#endif

// Dummy sockaddr for sendto in link level
static struct sockaddr_ll sockaddr;

int send_run_init(sock_t s) {
    // Get the actual socket
    int sock = s.sock;
    // get source interface index
    struct ifreq if_idx;
    memset(&if_idx, 0, sizeof(struct ifreq));
    if (strlen(xconf.iface) >= IFNAMSIZ) {
        log_error("send", "device interface name (%s) too long\n", xconf.iface);
        return EXIT_FAILURE;
    }
    strncpy(if_idx.ifr_name, xconf.iface, IFNAMSIZ - 1);
    if (ioctl(sock, SIOCGIFINDEX, &if_idx) < 0) {
        perror("SIOCGIFINDEX");
        return EXIT_FAILURE;
    }
    int ifindex = if_idx.ifr_ifindex;

    // destination address for the socket
    memset((void *) &sockaddr, 0, sizeof(struct sockaddr_ll));
    sockaddr.sll_ifindex = ifindex;
    sockaddr.sll_halen   = ETH_ALEN;
    if (xconf.send_ip_pkts) {
        switch (xconf.ipv46_flag) {
        case IPV6_FLAG:
            sockaddr.sll_protocol = htons(ETHERTYPE_IPV6);
            break;
        case IPV4_FLAG:
            sockaddr.sll_protocol = htons(ETHERTYPE_IP);
            break;
        default:
            log_fatal("socket", "iplayer for linux not supported on IPv%d",
                      xconf.ipv46_flag);
        }
    }
    memcpy(sockaddr.sll_addr, xconf.gw_mac, ETH_ALEN);
    return EXIT_SUCCESS;
}

int send_packet(sock_t sock, void *buf, int len, UNUSED uint32_t idx) {
    return sendto(sock.sock, buf, len, 0, (struct sockaddr *) &sockaddr,
                  sizeof(struct sockaddr_ll));
}

#endif // XMAP_SEND_LINUX_H