// sntp_malformed.c
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <arpa/inet.h>
#include <unistd.h>

#define NTP_PORT 123

int main(int argc, char *argv[]) {
    if (argc != 2) {
        printf("Usage: %s <server_ip>\n", argv[0]);
        return 1;
    }

    int sockfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
    struct sockaddr_in server;
    char malformed[20] = {0}; // Less than 48 bytes

    server.sin_family = AF_INET;
    server.sin_port = htons(NTP_PORT);
    inet_pton(AF_INET, argv[1], &server.sin_addr);

    sendto(sockfd, malformed, sizeof(malformed), 0, (struct sockaddr *)&server, sizeof(server));
    printf("Malformed packet (20 bytes) sent to %s\n", argv[1]);
    close(sockfd);
    return 0;
}