PrivateAddressCheck

Checks if a URL or hostname would cause a request to a private network (RFC 1918). This is useful in preventing attacks like Server Side Request Forgery.

Requirements

Ruby >= 2.0

Installation

Add this line to your application's Gemfile:

gem 'private_address_check'

And then execute:

$ bundle

Or install it yourself as:

$ gem install private_address_check

Usage

require "private_address_check"

PrivateAddressCheck.private_address?("8.8.8.8") # => false
PrivateAddressCheck.private_address?("10.10.10.2") # => true
PrivateAddressCheck.private_address?("127.0.0.1") # => true
PrivateAddressCheck.private_address?("172.16.2.10") # => true
PrivateAddressCheck.private_address?("192.168.1.10") # => true
PrivateAddressCheck.private_address?("fd00::2") # => true
PrivateAddressCheck.resolves_to_private_address?("github.com") # => false
PrivateAddressCheck.resolves_to_private_address?("localhost") # => true

require "private_address_check/tcpsocket_ext"
require "net/http"
require "uri"

Net::HTTP.get_response(URI.parse("http://192.168.1.1")) # => attempts connection like normal

PrivateAddressCheck.only_public_connections do
  Net::HTTP.get_response(URI.parse("http://192.168.1.1"))
end
# => raises PrivateAddressCheck::PrivateConnectionAttemptedError

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake test to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/jtdowney/private_address_check. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

License

The gem is available as open source under the terms of the MIT License.

anthrax3 / private_address_check Goto Github PK