> For the complete documentation index, see [llms.txt](https://pcastagnaro.gitbook.io/pentest-bug-bounty-resources/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://pcastagnaro.gitbook.io/pentest-bug-bounty-resources/pentest-bounty-resources/web/http-s-dos.md).

# HTTP/S DoS

## HTTP/S Ping

When performing stress testing or DoS simulations, the following commands ar used to make HTTP requests and measure website performance. Its main objectives include:

1. Sending HTTP/HTTPS requests to a web server.
2. Measuring response times and performance metrics
3. Obtaining HTTP status codes and response sizes.
4. Performing performance tests and comparisons between websites.

While curl can be used for stress testing or DoS simulations, it's crucial to emphasize that such activities without authorization are illegal and unethical. However, for authorized load testing, curl can be employed in the following ways:

1. Performing multiple requests in a loop to simulate heavy traffic.
2. Using the --limit-rate option to test server behavior under different connection speeds.
3. Combining curl with tools like "ntimes" to execute a specific number of requests and analyze response time percentiles.

### Using cURL

Using `curl` can provide a more accurate measurement of round-trip time compared to the `wget` method (refer to [#using-wget](#using-wget "mention")). `curl` offers built-in timing options that can give you precise information about various stages of the HTTP request.

#### One-line Command

Here's a one-line command using `curl` to measure the round-trip time:

{% code overflow="wrap" lineNumbers="true" %}

```bash
while true; do response=$(curl -s -o /dev/null -w "Status:%{http_code}; Time:%{time_total}; DNS:%{time_namelookup}; Connect:%{time_connect}; TTFB:%{time_starttransfer}" https://site.com); echo "$(date '+%Y-%m-%d %H:%M:%S'); $response"; sleep 0; done
```

{% endcode %}

This command:

1. Uses `curl`'s `-w` option to format the output, showing the HTTP status code and total time.
2. The `-s` option silences curl's progress meter.
3. `-o /dev/null` redirects the response body to `/dev/null`, as we're only interested in timing information.
4. **DNS Lookup time**: Time taken for DNS resolution.
5. **Connect time:** Time to establish the TCP connection.
6. **TTFB (Time to First Byte):** Time until the first byte is received.
7. **Total time:** Overall time for the entire request.

The output will look something like this:

{% code overflow="wrap" %}

```
2025-01-27 11:15:39; Status:200; Time:0.841107; DNS:0.025360; Connect:0.141437; TTFB:0.841054
```

{% endcode %}

### Using wget

#### One-line command

{% code overflow="wrap" lineNumbers="true" %}

```bash
url="https://site.com"; while true; do start=$(date +%s%N); status=$(wget -qS --spider "${url}" 2>&1 | grep "HTTP/" | awk '{print $2}'); end=$(date +%s%N); duration=$(( (end - start) / 1000000 )); echo "$(date '+%Y-%m-%d %H:%M:%S') - Site status: $status - Response time: ${duration}ms"; sleep 60; done
```

{% endcode %}

#### Script

{% code overflow="wrap" lineNumbers="true" %}

```bash
while true; do
  start=$(date +%s%N)
  status=$(wget -qS --spider http://example.com 2>&1 | grep "HTTP/" | awk '{print $2}')
  end=$(date +%s%N)
  duration=$(( (end - start) / 1000000 ))
  echo "$(date '+%Y-%m-%d %H:%M:%S') - Site status: $status - Response time: ${duration}ms"
  sleep 60
done
```

{% endcode %}

This script does the following:

1. `start=$(date +%s%N)`: Captures the start time in nanoseconds.
2. The `wget` command is executed and the status code is stored in the `status` variable.
3. `end=$(date +%s%N)`: Captures the end time in nanoseconds.
4. `duration=$(( (end - start) / 1000000 ))`: Calculates the duration in milliseconds.

This script will continuously check the website's status and response time, printing a line like this every `X` seconds:

```
2025-01-27 11:30:45 - Site status: 200 - Response time: 123ms
```

Remember, you can adjust the sleep interval (currently set to `60` seconds) as needed. If uses `0` it won't do any pause. To stop the script, use `Ctrl+C` in the terminal.

Note: The response time measured this way includes the time taken by wget to process the response, not just the network round-trip time. For more precise network timing, you might want to consider using specialized tools like `curl` with its timing options.