~srushe/indieauth-token-verification

f248a5476f4d58f5daaf4c34e3a90ba2b3391e89 — Stephen Rushe 2 years ago
Initial release
A  => .gitignore +12 -0
@@ 1,12 @@
/.bundle/
/.yardoc
/Gemfile.lock
/_yardoc/
/coverage/
/doc/
/pkg/
/spec/reports/
/tmp/

# rspec failure tracking
.rspec_status

A  => .rspec +2 -0
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--format documentation
--color

A  => .ruby-gemset +1 -0
@@ 1,1 @@
indieauth-token-verification

A  => .ruby-version +1 -0
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ruby-2.5.3

A  => CHANGELOG.md +27 -0
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# Changelog
All notable changes to this project will be documented in this file.

The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).

## [Unreleased]

## [0.2.0] - 2019-01-24

### Added
- Added explicit message to IncorrectMeError.

## [0.1.2] - 2018-05-18

### Added
- Use `kind_of?` rather than `code` when checking response from token endpoint.

## [0.1.1] - 2018-03-04

### Added
- Forced use of SSL on the token endpoint.

## [0.1.0] - 2018-02-20

### Added
- Initial release.

A  => CODE_OF_CONDUCT.md +74 -0
@@ 1,74 @@
# Contributor Covenant Code of Conduct

## Our Pledge

In the interest of fostering an open and welcoming environment, we as
contributors and maintainers pledge to making participation in our project and
our community a harassment-free experience for everyone, regardless of age, body
size, disability, ethnicity, gender identity and expression, level of experience,
nationality, personal appearance, race, religion, or sexual identity and
orientation.

## Our Standards

Examples of behavior that contributes to creating a positive environment
include:

* Using welcoming and inclusive language
* Being respectful of differing viewpoints and experiences
* Gracefully accepting constructive criticism
* Focusing on what is best for the community
* Showing empathy towards other community members

Examples of unacceptable behavior by participants include:

* The use of sexualized language or imagery and unwelcome sexual attention or
advances
* Trolling, insulting/derogatory comments, and personal or political attacks
* Public or private harassment
* Publishing others' private information, such as a physical or electronic
  address, without explicit permission
* Other conduct which could reasonably be considered inappropriate in a
  professional setting

## Our Responsibilities

Project maintainers are responsible for clarifying the standards of acceptable
behavior and are expected to take appropriate and fair corrective action in
response to any instances of unacceptable behavior.

Project maintainers have the right and responsibility to remove, edit, or
reject comments, commits, code, wiki edits, issues, and other contributions
that are not aligned to this Code of Conduct, or to ban temporarily or
permanently any contributor for other behaviors that they deem inappropriate,
threatening, offensive, or harmful.

## Scope

This Code of Conduct applies both within project spaces and in public spaces
when an individual is representing the project or its community. Examples of
representing a project or community include using an official project e-mail
address, posting via an official social media account, or acting as an appointed
representative at an online or offline event. Representation of a project may be
further defined and clarified by project maintainers.

## Enforcement

Instances of abusive, harassing, or otherwise unacceptable behavior may be
reported by contacting the project team at coc+tokenverification@deeden.co.uk. All
complaints will be reviewed and investigated and will result in a response that
is deemed necessary and appropriate to the circumstances. The project team is
obligated to maintain confidentiality with regard to the reporter of an incident.
Further details of specific enforcement policies may be posted separately.

Project maintainers who do not follow or enforce the Code of Conduct in good
faith may face temporary or permanent repercussions as determined by other
members of the project's leadership.

## Attribution

This Code of Conduct is adapted from the [Contributor Covenant][homepage], version 1.4,
available at [http://contributor-covenant.org/version/1/4][version]

[homepage]: http://contributor-covenant.org
[version]: http://contributor-covenant.org/version/1/4/

A  => Gemfile +4 -0
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source 'https://rubygems.org'

# Specify your gem's dependencies in indieauth-token-verification.gemspec
gemspec

A  => LICENSE.txt +21 -0
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The MIT License (MIT)

Copyright (c) 2018 Stephen Rushe

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.

A  => README.md +60 -0
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# IndieAuth::TokenVerification

Verify an IndieAuth access token against a token endpoint, ensuring that the scope required is one of those associated with the token.

## Installation

Add this line to your application's Gemfile:

```ruby
gem 'indieauth-token-verification'
```

And then execute:

    $ bundle

Or install it yourself as:

    $ gem install indieauth-token-verification

## Configuration

Use of the gem **requires** two environment variables to be specified, `TOKEN_ENDPOINT`, and `DOMAIN`.

`TOKEN_ENDPOINT` specifies the token endpoint to be used to validate the access token. Failure to specify `TOKEN_ENDPOINT` will result in a `IndieAuth::TokenVerification::MissingTokenEndpointError` error being raised.

`DOMAIN` specifies the domain we expect to see in the response from the validated token. It should match that specified when the token was first generated. Failure to specify `DOMAIN` will result in a `IndieAuth::TokenVerification::MissingDomainError` error being raised.

## Usage

```ruby
# Verify the provided access token, with no scope requirement
IndieAuth::TokenVerification.new(access_token).verify

# Verify the provided access token, requiring a particular scope
IndieAuth::TokenVerification.new(access_token).verify("media")
```

## Errors

As well as `MissingTokenEndpointError` and `MissingDomainError` mentioned above, there are other errors which will be raised in certain circumstances...

* `IndieAuth::TokenVerification::AccessTokenMissingError` - when the access token is missing
* `IndieAuth::TokenVerification::ForbiddenUserError` - when the token endpoint reports an error
* `IndieAuth::TokenVerification::IncorrectMeError` - when the `me` value in the response does not match the `DOMAIN`
* `IndieAuth::TokenVerification::InsufficentScopeError` - when the scope requested is not granted by the access token

## 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 tags, and push the `.gem` file to [rubygems.org](https://rubygems.org).

## Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/srushe/indieauth-token-verification. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the [Contributor Covenant](http://contributor-covenant.org) code of conduct.

## License

The gem is available as open source under the terms of the [MIT License](http://opensource.org/licenses/MIT).

A  => Rakefile +6 -0
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require "bundler/gem_tasks"
require "rspec/core/rake_task"

RSpec::Core::RakeTask.new(:spec)

task :default => :spec

A  => bin/console +14 -0
@@ 1,14 @@
#!/usr/bin/env ruby

require "bundler/setup"
require "indie_auth/token_verification"

# You can add fixtures and/or initialization code here to make experimenting
# with your gem easier. You can also use a different console, if you like.

# (If you use this, don't forget to add pry to your Gemfile!)
# require "pry"
# Pry.start

require "irb"
IRB.start(__FILE__)

A  => bin/setup +8 -0
@@ 1,8 @@
#!/usr/bin/env bash
set -euo pipefail
IFS=$'\n\t'
set -vx

bundle install

# Do any other automated setup that you need to do here

A  => indieauth-token-verification.gemspec +38 -0
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# coding: utf-8
lib = File.expand_path('../lib', __FILE__)
$LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
require 'indie_auth/token_verification/version'

Gem::Specification.new do |spec|
  spec.name          = "indieauth-token-verification"
  spec.version       = IndieAuth::TokenVerification::VERSION
  spec.authors       = ["Stephen Rushe"]
  spec.email         = ["steve+gemspec@deeden.co.uk"]

  spec.summary       = %q{Perform the access token verification portion of the IndieAuth process.}
  spec.description   = %q{Perform the access token verification portion of the IndieAuth process by communicationg with a token endpoint.}
  spec.homepage      = "https://github.com/srushe/indieauth-token-verification"
  spec.license       = "MIT"

  # Prevent pushing this gem to RubyGems.org. To allow pushes either set the 'allowed_push_host'
  # to allow pushing to a single host or delete this section to allow pushing to any host.
  if spec.respond_to?(:metadata)
    spec.metadata['allowed_push_host'] = ENV.fetch('GEMSERVER_URL', 'nohost')
  else
    raise "RubyGems 2.0 or newer is required to protect against " \
      "public gem pushes."
  end

  spec.files         = `git ls-files -z`.split("\x0").reject do |f|
    f.match(%r{^(test|spec|features)/})
  end
  spec.bindir        = "exe"
  spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
  spec.require_paths = ["lib"]

  spec.add_development_dependency "bundler", "~> 2.0"
  spec.add_development_dependency "climate_control"
  spec.add_development_dependency "pry"
  spec.add_development_dependency "rake", "~> 12.3"
  spec.add_development_dependency "rspec", "~> 3.0"
end

A  => lib/indie_auth/token_verification.rb +61 -0
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require 'indie_auth/token_verification/version'
require 'net/http'
require 'json'

module IndieAuth
  class TokenVerification
    class AccessTokenMissingError < StandardError; end
    class ForbiddenUserError < StandardError; end
    class IncorrectMeError < StandardError; end
    class InsufficentScopeError < StandardError; end
    class MissingDomainError < StandardError; end
    class MissingTokenEndpointError < StandardError; end

    attr_reader :access_token

    def initialize(access_token)
      @access_token = access_token.to_s.strip.sub(/\ABearer\s*/, '')
    end

    def verify(desired_scope=nil)
      raise AccessTokenMissingError if access_token.nil? or access_token.empty?
      raise MissingDomainError if ENV.fetch('DOMAIN', nil).nil?
      raise MissingTokenEndpointError if ENV.fetch('TOKEN_ENDPOINT', nil).nil?

      response = validate_token
      raise ForbiddenUserError unless response.kind_of? Net::HTTPSuccess

      response_body = JSON.parse(response.body)
      if response_body.fetch('me', nil) != ENV['DOMAIN']
        raise IncorrectMeError, "Expected: '#{ENV['DOMAIN']}', Received: '#{response_body.fetch('me', nil)}'"
      end

      return true if desired_scope.nil?
      scope_included_in_response?(response_body, desired_scope)
    end

    private

    def validate_token
      uri = URI.parse(ENV['TOKEN_ENDPOINT'])
      http = Net::HTTP.new(uri.host, uri.port)
      http.use_ssl = true
      http.get(uri.request_uri, {'Accept' => 'application/json', 'Authorization' => "Bearer #{access_token}"})
    end

    def scope_included_in_response?(response, desired_scope)
      scopes = scopes_from(response)

      return true if scopes.include?(desired_scope)
      return true if desired_scope == 'post' && scopes.include?('create')
      raise InsufficentScopeError
    end

    def scopes_from(response_body)
      return @scopes if defined? @scopes
      raise InsufficentScopeError unless response_body.key?('scope')

      @scopes ||= response_body['scope'].split
    end
  end
end
\ No newline at end of file

A  => lib/indie_auth/token_verification/version.rb +5 -0
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module IndieAuth
  class TokenVerification
    VERSION = "0.2.0"
  end
end

A  => spec/indie_auth/token_verification_spec.rb +155 -0
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require 'spec_helper'

def with_modified_environment(options, &block)
  ClimateControl.modify(options, &block)
end

RSpec.shared_examples_for 'a successful verification' do
  context 'the token endpoint is used to verify the token' do
    let(:expected_headers) do
      {
        'Accept' => 'application/json',
        'Authorization' => 'Bearer some-token'
      }
    end

    before do
      verifier.verify
    end

    it { expect(Net::HTTP).to have_received(:new).with(token_endpoint_uri.host, token_endpoint_uri.port) }
    it { expect(http_object).to have_received(:use_ssl=).with(true) }
    it { expect(http_object).to have_received(:get).with(token_endpoint_uri.request_uri, expected_headers) }
  end

  context 'when a scope is provided' do
    subject { verifier.verify('create') }

    it { expect(subject).to be true }
  end

  context 'when no scope is provided' do
    subject { verifier.verify }

    it { expect(subject).to be true }
  end
end

RSpec.describe IndieAuth::TokenVerification do
  it "has a version number" do
    expect(IndieAuth::TokenVerification::VERSION).not_to be nil
  end

  let(:domain) { 'https://example.org/' }
  let(:token_endpoint_url) { 'https://example.com/token' }
  let(:token_endpoint_uri) { instance_double(URI::HTTPS, request_uri: '/token', host: 'example.org', port: 443) }
  let(:http_object) { instance_double(Net::HTTP) }
  let(:token_response) do
    double(:http_response, body: response_body)
  end
  let(:response_successful) { true }
  let(:response_body) { "{\"scope\":\"create update delete undelete\",\"me\":\"#{domain}\"}" }

  before do
    allow(URI).to receive(:parse) { token_endpoint_uri }
    allow(Net::HTTP).to receive(:new) { http_object }
    allow(http_object).to receive(:use_ssl=)
    allow(http_object).to receive(:get) { token_response }
    allow(token_response).to receive(:kind_of?).with(Net::HTTPSuccess) { response_successful }
  end

  context 'when no error occurs' do
    let(:verifier) { described_class.new(access_token) }
    let(:environment) do
      { TOKEN_ENDPOINT: token_endpoint_url, DOMAIN: domain }
    end

    around do |example|
      with_modified_environment(environment) { example.run }
    end

    context 'and the access_token starts with "Bearer "' do
      let(:access_token) { 'Bearer some-token' }

      it_behaves_like 'a successful verification'
    end

    context 'and the access is plain' do
      let(:access_token) { 'some-token' }

      it_behaves_like 'a successful verification'
    end
  end

  context 'when an error occurs' do
    let(:verifier) { described_class.new(access_token) }
    let(:access_token) { 'some.token' }

    context 'due to the access_token being invalid' do
      subject(:verify) { verifier.verify }

      ['', '   ', nil, 'Bearer', 'Bearer   '].each do |invalid_access_token|
        context "when it is '#{invalid_access_token.nil? ? 'nil' : invalid_access_token}'" do
          let(:access_token) { invalid_access_token }

          it { expect { verify }.to raise_error(IndieAuth::TokenVerification::AccessTokenMissingError) }
        end
      end
    end

    context 'due to the DOMAIN environment variable not being set' do
      subject(:verify) { verifier.verify }

      it 'raises the correct error' do
        with_modified_environment(TOKEN_ENDPOINT: token_endpoint_url) do
          expect { verify }.to raise_error(IndieAuth::TokenVerification::MissingDomainError)
        end
      end
    end

    context 'due to no TOKEN_ENDPOINT being defined' do
      subject(:verify) { verifier.verify }

      it 'raises the correct error' do
        with_modified_environment(DOMAIN: domain) do
          expect { verify }.to raise_error(IndieAuth::TokenVerification::MissingTokenEndpointError)
        end
      end
    end

    context 'due to the token endpoint not responding with success' do
      subject(:verify) { verifier.verify }

      let(:response_successful) { false }
      let(:response_body) { nil }

      it 'raises the correct error' do
        with_modified_environment(DOMAIN: domain, TOKEN_ENDPOINT: token_endpoint_url) do
          expect { verify }.to raise_error(IndieAuth::TokenVerification::ForbiddenUserError)
        end
      end
    end

    context 'due to the me value not matching DOMAIN' do
      subject(:verify) { verifier.verify }

      let(:response_body) { "{\"scope\":\"create update delete undelete\",\"me\":\"https://other.example.com/\"}" }

      it 'raises the correct error' do
        with_modified_environment(DOMAIN: domain, TOKEN_ENDPOINT: token_endpoint_url) do
          expect { verify }.to raise_error(IndieAuth::TokenVerification::IncorrectMeError, "Expected: '#{domain}', Received: 'https://other.example.com/'")
        end
      end
    end

    context 'due to the scope requested not being acceptable' do
      subject(:verify) { verifier.verify('media') }

      it 'raises the correct error' do
        with_modified_environment(DOMAIN: domain, TOKEN_ENDPOINT: token_endpoint_url) do
          expect { verify }.to raise_error(IndieAuth::TokenVerification::InsufficentScopeError)
        end
      end
    end
  end
end

A  => spec/spec_helper.rb +12 -0
@@ 1,12 @@
require "bundler/setup"
require "indie_auth/token_verification"
require "climate_control"

RSpec.configure do |config|
  # Enable flags like --only-failures and --next-failure
  config.example_status_persistence_file_path = ".rspec_status"

  config.expect_with :rspec do |c|
    c.syntax = :expect
  end
end