cloudflare-bot-protect-check

A simple cli tool to check which user agents are valid for cloudflare protected websites.

About

This tool is developed with a special focus on our projects like crunchyroll-rs or crunchy-cli to see how to bypass the bot protection installed for www.crunchyroll.com. But nevertheless it can be used for other sites and projects too. Especially Rust projects which need to bypass the cloudflare bot check might benefit from this tool as it uses reqwest and rustls which behaves other than e.g. the python requests package.

Installation

To build this tool, git and Cargo are required. If these requirements are met, continue with executing the following commands.

$ git clone https://github.com/crunchy-labs/cloudflare-bot-protect-check
$ cd cloudflare-bot-protect-check
# either just build it (will be available in ./target/release/cloudflare-bot-protect-check)...
$ cargo build --release
# ... or install it globally
$ cargo install --force --path .

Usage

By default, this tool reads user agents from stdin.

# user agent from stdin
$ echo "Mozilla/5.0 (X11; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/115.0" | cloudflare-bot-protect-check https://www.crunchyroll.com

If you want to read the user agents from a file, use the --file flag. The file must be text file where every line contains one user agent.

# assuming that the file 'useragents.txt' with the following content exists
$ cat useragents.txt
Mozilla/5.0 (X11; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/115.0
Mozilla/5.0 (Macintosh; Intel Mac OS X 13.4; rv:109.0) Gecko/20100101 Firefox/115.0
Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:109.0) Gecko/20100101 Firefox/115.0
# read the user agents from 'useragents.txt'
$ cloudflare-bot-protect-check --file useragents.txt https://www.crunchyroll.com

The default output format is plain text. Use the --format flag to change the output format. Available formats are plain and json.

$ cloudflare-bot-protect-check --format json https://www.crunchyroll.com

Some flags to set custom tls settings are available too. You need to set the --custom-tls flag to activate the custom tls settings. Use cloudflare-bot-protect-check --help to see all available flag values.

$ cloudflare-bot-protect-check --custom-tls https://www.crunchyroll.com
# set specific cipher suite(s) with `--cipher-suite`
$ cloudflare-bot-protect-check --custom-tls --cipher-suite tls13-aes-256-gcm-sha384 https://www.crunchyroll.com
# set specific key exchange group(s) with `--kx-group`
$ cloudflare-bot-protect-check --custom-tls --kx-group x25519 https://www.crunchyroll.com
# set specific tls version(s) with `--tls`
$ cloudflare-bot-protect-check --custom-tls --tls tls12 --tls tls13 https://www.crunchyroll.com

Resources

Where to get user agents

• whatsismybrowser.com has a large user agent database with is also available via an api (only limited access, also has a paid plan)
• useragents.me provides the most common and latest used user agents as json. You can use the following expression to get all user agents from an useragents.me user agent json list

  $ cat <json-from-useragents.me-as-file> | grep -oP '(?<="ua":\s").+?(?=")'

License

This project is licensed under the MIT License - see the LICENSE file for more details.