Check If There Is Any Banner Available Or Not In CPP

banner-grabber.cpp

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <time.h>

// github : https://github.com/R3DHULK/

#define PORT 80 // the port number to connect to
#define BUFSIZE 1024

int main(int argc, char *argv[])
{
    int sockfd;
    struct sockaddr_in target_addr;
    struct hostent *target;
    char buf[BUFSIZE];
    int numbytes;

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

    if ((target = gethostbyname(argv[1])) == NULL) {
        perror("gethostbyname");
        return 1;
    }

    if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
        perror("socket");
        return 1;
    }

    target_addr.sin_family = AF_INET;
    target_addr.sin_port = htons(PORT);
    target_addr.sin_addr = *((struct in_addr *)target->h_addr);
    memset(&(target_addr.sin_zero), '\0', 8);

    if (connect(sockfd, (struct sockaddr *)&target_addr, sizeof(struct sockaddr)) == -1) {
        perror("connect");
        return 1;
    }

    // send a simple HTTP request to retrieve the banner
    sprintf(buf, "HEAD / HTTP/1.0\r\n\r\n");
    send(sockfd, buf, strlen(buf), 0);

    if ((numbytes = recv(sockfd, buf, BUFSIZE - 1, 0)) == -1) {
        perror("recv");
        return 1;
    }

    buf[numbytes] = '\0';
    printf("Banner:\n%s\n", buf);

    close(sockfd);

    return 0;
}