M2mKeygen

This gem exists for simplifying Machine to Machine signature generation and verification in a secure way.

Installation

Install the gem and add to the application's Gemfile by executing:

$ bundle add m2m_keygen

If bundler is not being used to manage dependencies, install the gem by executing:

$ gem install m2m_keygen

Usage

Signature

This gem provides a module for signing and checking signature for HTTP requests

Initialization

You should initialize the Signature once (in an initializer for example) with your secret key and eventually an encryption algorithm.

AuthSignature = M2mKeygen::Signature.new("my_secret_key", algorithm: "sha256")

AuthSignature = M2mKeygen::Signature.new("my_secret_key") # => Will default algorithm to sha512

Signing

Use the sign method to generate a new signature.

• params is a params hash as used in Rack. The order of keys isn't important as the gem will reformat them.
• verb is the http verb
• path is the path for the request

AuthSignature.sign(
  params: {
    "a" => "test",
    :b => 1,
    "d" => %w[a b],
    "c" => {
      "e" => 45
    }
  },
  verb: "get",
  path: "/path"
) # => "a52168521868ebb37a38f90ec943163d9acb6ceb982206f437e1feb9ca32e7c1a8edef68f0ff4e195aeca1da93ae9afc8da214cb51a812fc6cc3730fdc7613fa"

After generating the signature send it alongside your request for verification on the receiver side.

Verifying

Use the validate method to verify that a received signature correspond to the HTTP request.

• params is a params hash as used in Rack. The order of keys isn't important as the gem will reformat them.
• verb is the http verb
• path is the path for the request
• signature is the received signature

AuthSignature.validate(
  params: {
    "a" => "test",
    :b => 1,
    "d" => %w[a b],
    "c" => {
      "e" => 45
    }
  },
  verb: "get",
  path: "/path",
  signature:
    "a52168521868ebb37a38f90ec943163d9acb6ceb982206f437e1feb9ca32e7c1a8edef68f0ff4e195aeca1da93ae9afc8da214cb51a812fc6cc3730fdc7613fa"
) #=> true

If the validation is true, the request was signed with the same algorithm and same secret key.

RackValidator

This module is here for directly validate Rack requests.

It will validate :

• Signature matching
• That the expiry parameter is present and between now and in 2 minutes.

Initialization

You should initialize the RackValidator once (in an initializer for example) with your secret key, eventually an encryption algorithm and a header name for the signature.

RackSignatureValidator =
  M2mKeygen::RackValidator.new(
    "secret",
    algorithm: "sha512", # Default value
    header_name: "X-Signature" # Default value
  )

Validation

You can then validate a Rack::Request or a Rails Request directly:

RackSignatureValidator.validate(request) # => true or false

How does it works

This is intended for a secure discussion between 2 servers and not something in a browser as the secret key must be stored and used both side (and you don't want to send the secret key in the browser).

Both server will have the same secret key. The sender will generate a signature matching the HTTP request it will be sending and add it to the request in a designated header. The receiver will generate the same signature from the HTTP request it has received and will compare it with the signature in the header.

The comparison will be done in constant time (i.e. secure) because both string will be hexdigest from a HMAC with the same algorithm.

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec 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 the created tag, and push the .gem file to rubygems.org.

Every commit/push is checked by overcommit. You should (must) activate overcommit by using overcommit -i post installation.

Tool used in dev:

• Rubocop
• Prettier
• Yard
• Sorbet
• RSpec

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/zaratan/m2m_keygen. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the code of conduct.

License

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

Code of Conduct

Everyone interacting in the M2mKeygen project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.