first commit

Sniffing_Spoofing/volumes/spoofer.c

@@ -0,0 +1,81 @@
+#include <stdio.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <netinet/ip.h>
+#include <netinet/ip_icmp.h>
+#include <arpa/inet.h>
+#include <unistd.h>
+
+/* Checksum calculation function */
+unsigned short in_cksum (unsigned short *buf, int length) {
+    unsigned short *w = buf;
+    int nleft = length;
+    int sum = 0;
+    unsigned short temp=0;
+
+    while (nleft > 1)  {
+        sum += *w++;
+        nleft -= 2;
+    }
+
+    if (nleft == 1) {
+        *(u_char *)(&temp) = *(u_char *)w ;
+        sum += temp;
+    }
+
+    sum = (sum >> 16) + (sum & 0xffff);
+    sum += (sum >> 16);
+    return (unsigned short)(~sum);
+}
+
+void send_raw_ip_packet(struct iphdr* ip) {
+    struct sockaddr_in dest_info;
+    int enable = 1;
+
+    int sock = socket(AF_INET, SOCK_RAW, IPPROTO_RAW);
+    if (sock < 0) {
+        perror("Socket creation failed");
+        return;
+    }
+
+    setsockopt(sock, IPPROTO_IP, IP_HDRINCL, &enable, sizeof(enable));
+
+    dest_info.sin_family = AF_INET;
+    dest_info.sin_addr.s_addr = ip->daddr;
+
+    if (sendto(sock, ip, ntohs(ip->tot_len), 0, (struct sockaddr *)&dest_info, sizeof(dest_info)) < 0) {
+        perror("Sendto failed");
+    } else {
+        printf("Spoofed ICMP packet sent.\n");
+    }
+    close(sock);
+}
+
+int main() {
+    char buffer[1500];
+    memset(buffer, 0, 1500);
+
+    struct iphdr *ip = (struct iphdr *) buffer;
+    struct icmphdr *icmp = (struct icmphdr *) (buffer + sizeof(struct iphdr));
+
+    // Construct ICMP Header
+    icmp->type = ICMP_ECHO;
+    icmp->code = 0;
+    icmp->un.echo.id = htons(1234);
+    icmp->un.echo.sequence = htons(1);
+    icmp->checksum = 0;
+    icmp->checksum = in_cksum((unsigned short *)icmp, sizeof(struct icmphdr));
+
+    // Construct IP Header
+    ip->version = 4;
+    ip->ihl = 5;
+    ip->ttl = 64;
+    ip->saddr = inet_addr("1.2.3.4");
+    ip->daddr = inet_addr("10.9.0.5");
+    ip->protocol = IPPROTO_ICMP;
+    ip->tot_len = htons(sizeof(struct iphdr) + sizeof(struct icmphdr));
+
+    send_raw_ip_packet(ip);
+
+    return 0;
+}