Bypassing Cloudflare Error 1020 Access Denied in Elixier

Are you tired of seeing the dreaded Cloudflare Error 1020 Access Denied message when trying to access certain websites using Elixir? Don't worry, you're not alone. Many developers face this issue, especially when scraping or automating interactions with Cloudflare-protected sites.

In this article, we'll explore various techniques to bypass the Cloudflare Error 1020 and successfully access the desired content using Elixir. We'll dive into the causes of this error and provide practical code examples to help you overcome it. So, let's get started!

Understanding Cloudflare Error 1020

Before we jump into the solutions, it's essential to understand what causes the Cloudflare Error 1020. Cloudflare is a popular web security and performance platform that sits between the client and the server. It acts as a reverse proxy, protecting websites from various threats and optimizing content delivery.

When Cloudflare detects suspicious activity, such as excessive requests or automated behavior, it may block the request and display the Error 1020 Access Denied message. This is a security measure to prevent abuse and protect the website from potential attacks.

Solution 1: Mimicking Browser Behavior

One approach to bypass the Cloudflare Error 1020 is to make your Elixir program mimic the behavior of a regular web browser. Cloudflare tends to be more lenient towards requests that appear to come from legitimate browsers. Here's how you can achieve this using the HTTPoison library:

defmodule CloudflareBypasser do
  use HTTPoison.Base

  @url "<https://example.com>"

  def bypass do
    headers = [
      {"User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/93.0.4577.82 Safari/537.36"},
      {"Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8"},
      {"Accept-Language", "en-US,en;q=0.5"},
      {"Accept-Encoding", "gzip, deflate, br"},
      {"Connection", "keep-alive"},
      {"Upgrade-Insecure-Requests", "1"},
      {"Cache-Control", "max-age=0"}
    ]

    response = get(@url, headers)
    IO.puts(response.body)
  end
end

CloudflareBypasser.bypass()

In this example, we set the User-Agent header to mimic a popular web browser. We also include other common headers like Accept, Accept-Language, and Accept-Encoding to make the request appear more authentic.

By sending these headers, we increase the chances of bypassing the Cloudflare Error 1020 and successfully retrieving the desired content.

Solution 2: Handling Cookies and Session

Another approach to bypass the Cloudflare Error 1020 is to handle cookies and maintain a session throughout the requests. Cloudflare often sets cookies to track and validate user sessions. By properly handling these cookies, you can establish a legitimate session and avoid being blocked. Here's an example using the HTTPoison library:

defmodule CloudflareBypasser do
  use HTTPoison.Base

  @url "<https://example.com>"

  def bypass do
    headers = [
      {"User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/93.0.4577.82 Safari/537.36"},
      # Other headers...
    ]

    options = [hackney: [cookie: ["session=your_session_id"]]]

    response = get(@url, headers, options)
    IO.puts(response.body)
  end
end

CloudflareBypasser.bypass()

In this example, we use the cookie option in the hackney options to set a session cookie with the name "session" and a value of "your_session_id". By providing a session cookie, we can maintain a persistent session across multiple requests.

By using a session and handling cookies, we can simulate a more natural browsing experience and reduce the chances of getting blocked by Cloudflare.

Solution 3: Solving Cloudflare Challenges

In some cases, Cloudflare presents a challenge page to verify that the request is coming from a human and not an automated script. To bypass this challenge, you need to solve it programmatically. Here's an example of how you can handle Cloudflare challenges using the HTTPoison library and Floki for parsing HTML:

defmodule CloudflareBypasser do
  use HTTPoison.Base

  @url "<https://example.com>"

  def bypass do
    headers = [
      {"User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/93.0.4577.82 Safari/537.36"},
      # Other headers...
    ]

    response = get(@url, headers)

    if response.body =~ "Cloudflare" do
      document = Floki.parse_document!(response.body)

      # Extract the challenge form
      challenge_form = Floki.find(document, "#challenge-form") |> hd()
      challenge_url = Floki.attribute(challenge_form, "action") |> hd()

      # Extract the challenge input
      jschl_vc = Floki.find(document, "input[name=jschl_vc]") |> hd() |> Floki.attribute("value") |> hd()
      pass = Floki.find(document, "input[name=pass]") |> hd() |> Floki.attribute("value") |> hd()

      # Extract the challenge script
      challenge_script = Floki.find(document, "script[type=text/javascript]") |> hd() |> Floki.text()

      # Solve the challenge
      answer = solve_challenge(challenge_script)

      # Build the challenge response URL
      challenge_response_url = "#{challenge_url}?jschl_vc=#{jschl_vc}&pass=#{pass}&jschl_answer=#{answer}"

      # Send the challenge response
      challenge_response = get(challenge_response_url, headers)

      IO.puts(challenge_response.body)
    else
      IO.puts(response.body)
    end
  end

  defp solve_challenge(challenge_script) do
    # Implement the logic to solve the challenge based on the provided script
    # This may involve evaluating JavaScript code or performing calculations
    # Return the solved challenge answer
    ""
  end
end

CloudflareBypasser.bypass()

In this example, we check if the response contains the word "Cloudflare" to detect if a challenge is presented. If a challenge is found, we use Floki to parse the HTML and extract the necessary information from the challenge form, such as the challenge URL, jschl_vc, and pass values.

We then extract the challenge script and pass it to a custom solve_challenge/1 function. This function should implement the logic to solve the specific challenge based on the provided script. It may involve evaluating JavaScript code or performing calculations to determine the correct answer.

Once the challenge is solved, we construct the challenge response URL by appending the necessary parameters (jschl_vc, pass, and jschl_answer) to the challenge URL. Finally, we send the challenge response using the constructed URL to bypass the Cloudflare challenge.

Additional Tips

Here are a few additional tips to keep in mind when dealing with Cloudflare Error 1020:

Conclusion

Bypassing Cloudflare Error 1020 Access Denied in Elixir can be challenging, but it's not impossible. By mimicking browser behavior, handling cookies and sessions, and solving Cloudflare challenges programmatically, you can increase your chances of successfully accessing the desired content.

Remember to use these techniques responsibly and respect the website's terms of service and robots.txt file. Scraping and automated interactions should be done ethically and with consideration for the website's resources and policies.

With the code examples and techniques provided in this article, you should be well-equipped to tackle the Cloudflare Error 1020 and proceed with your Elixir-based web scraping or automation tasks. Happy coding!