SQL Injection Vulnerability Scanner in C

sqli-vul-scan.c

#include <stdio.h>
#include <string.h>

#define PAYLOAD_LEN 100

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

    if (argc != 2) {
        fprintf(stderr, "Usage: %s <input string>\n", argv[0]);
        return 1;
    }

    strncpy(payload, argv[1], PAYLOAD_LEN);

    if (strstr(payload, ";") != NULL || strstr(payload, "--") != NULL ||
        strstr(payload, "union") != NULL || strstr(payload, "select") != NULL ||
        strstr(payload, "from") != NULL || strstr(payload, "where") != NULL) {
        printf(" [+] Possible SQL injection vulnerability found!\n");
    } else {
        printf(" [-] No SQL injection vulnerability found.\n");
    }

    return 0;
}