AndroidKeyAttestation

A Ruby gem to verify Android Key attestation statements on your server. Key attestation allows you to verify that the cryptographic keys you use in apps are stored the a hardware keystore of an Android device.

Add this line to your application's Gemfile:

gem 'android_key_attestation'

And then execute:

$ bundle install

Or install it yourself as:

$ gem install android_key_attestation

Request an attestation statement as described in the Android developer documentation and send the certificate chain to your server application.

In your server application code, do the following:

require "android_key_attestation"

statement = AndroidKeyAttestation::Statement.new(certificates)

# Verify the attestation certificate was issued for the challenge you generated
begin
  statement.verify(challenge)
rescue AndroidKeyAttestation::ChallengeMismatchError => e
  # abort
end

# Inspect properties of the attestation certificate belonging to the generated key pair, see
# https://developer.android.com/training/articles/security-key-attestation#certificate_schema_keydescription
# for more details. The gem uses snake_case versions of the lowerCamelCase names in the above link. 
statement.attestation_version
# => 3
statement.attestation_security_level
# => :trusted_environment
statement.tee_enforced.purpose
# => [:sign, :verify]
statement.tee_enforced.origin
# => :generated
statement.software_enforced.creation_date
# => 2018-07-29 08:31:54 -0400

After checking out the repo, run bin/setup to install dependencies. Then, run bin/rspec 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.

Bug reports and pull requests are welcome on GitHub at https://github.com/bdewater/android_key_attestation. 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.

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

The gem and its authors are unaffiliated with Google.